Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Linux Socket Filter - Kernel level socket filtering |
| 3 | * |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 4 | * Based on the design of the Berkeley Packet Filter. The new |
| 5 | * internal format has been designed by PLUMgrid: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 6 | * |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 7 | * Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com |
| 8 | * |
| 9 | * Authors: |
| 10 | * |
| 11 | * Jay Schulist <jschlst@samba.org> |
| 12 | * Alexei Starovoitov <ast@plumgrid.com> |
| 13 | * Daniel Borkmann <dborkman@redhat.com> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 14 | * |
| 15 | * This program is free software; you can redistribute it and/or |
| 16 | * modify it under the terms of the GNU General Public License |
| 17 | * as published by the Free Software Foundation; either version |
| 18 | * 2 of the License, or (at your option) any later version. |
| 19 | * |
| 20 | * Andi Kleen - Fix a few bad bugs and races. |
Alexei Starovoitov | 4df95ff | 2014-07-30 20:34:14 -0700 | [diff] [blame] | 21 | * Kris Katterjohn - Added many additional checks in bpf_check_classic() |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | */ |
| 23 | |
| 24 | #include <linux/module.h> |
| 25 | #include <linux/types.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 26 | #include <linux/mm.h> |
| 27 | #include <linux/fcntl.h> |
| 28 | #include <linux/socket.h> |
| 29 | #include <linux/in.h> |
| 30 | #include <linux/inet.h> |
| 31 | #include <linux/netdevice.h> |
| 32 | #include <linux/if_packet.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 33 | #include <linux/gfp.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | #include <net/ip.h> |
| 35 | #include <net/protocol.h> |
Patrick McHardy | 4738c1d | 2008-04-10 02:02:28 -0700 | [diff] [blame] | 36 | #include <net/netlink.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 37 | #include <linux/skbuff.h> |
| 38 | #include <net/sock.h> |
Jiri Pirko | 10b89ee4 | 2015-05-12 14:56:09 +0200 | [diff] [blame] | 39 | #include <net/flow_dissector.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | #include <linux/errno.h> |
| 41 | #include <linux/timer.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | #include <asm/uaccess.h> |
Dmitry Mishin | 40daafc | 2006-04-18 14:50:10 -0700 | [diff] [blame] | 43 | #include <asm/unaligned.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 44 | #include <linux/filter.h> |
David S. Miller | 86e4ca6 | 2011-05-26 15:00:31 -0400 | [diff] [blame] | 45 | #include <linux/ratelimit.h> |
Will Drewry | 46b325c | 2012-04-12 16:47:52 -0500 | [diff] [blame] | 46 | #include <linux/seccomp.h> |
Eric Dumazet | f333503 | 2012-10-27 02:26:17 +0000 | [diff] [blame] | 47 | #include <linux/if_vlan.h> |
Alexei Starovoitov | 89aa075 | 2014-12-01 15:06:35 -0800 | [diff] [blame] | 48 | #include <linux/bpf.h> |
Alexei Starovoitov | d691f9e | 2015-06-04 10:11:54 -0700 | [diff] [blame] | 49 | #include <net/sch_generic.h> |
Daniel Borkmann | 8d20aab | 2015-07-15 14:21:42 +0200 | [diff] [blame] | 50 | #include <net/cls_cgroup.h> |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 51 | #include <net/dst_metadata.h> |
Daniel Borkmann | c46646d | 2015-09-30 01:41:51 +0200 | [diff] [blame] | 52 | #include <net/dst.h> |
Craig Gallek | 538950a | 2016-01-04 17:41:47 -0500 | [diff] [blame] | 53 | #include <net/sock_reuseport.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 54 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 55 | /** |
Willem de Bruijn | f4979fc | 2016-07-12 18:18:56 -0400 | [diff] [blame] | 56 | * sk_filter_trim_cap - run a packet through a socket filter |
Stephen Hemminger | 43db6d6 | 2008-04-10 01:43:09 -0700 | [diff] [blame] | 57 | * @sk: sock associated with &sk_buff |
| 58 | * @skb: buffer to filter |
Willem de Bruijn | f4979fc | 2016-07-12 18:18:56 -0400 | [diff] [blame] | 59 | * @cap: limit on how short the eBPF program may trim the packet |
Stephen Hemminger | 43db6d6 | 2008-04-10 01:43:09 -0700 | [diff] [blame] | 60 | * |
Alexei Starovoitov | ff936a0 | 2015-10-07 10:55:41 -0700 | [diff] [blame] | 61 | * Run the eBPF program and then cut skb->data to correct size returned by |
| 62 | * the program. If pkt_len is 0 we toss packet. If skb->len is smaller |
Stephen Hemminger | 43db6d6 | 2008-04-10 01:43:09 -0700 | [diff] [blame] | 63 | * than pkt_len we keep whole skb->data. This is the socket level |
Alexei Starovoitov | ff936a0 | 2015-10-07 10:55:41 -0700 | [diff] [blame] | 64 | * wrapper to BPF_PROG_RUN. It returns 0 if the packet should |
Stephen Hemminger | 43db6d6 | 2008-04-10 01:43:09 -0700 | [diff] [blame] | 65 | * be accepted or -EPERM if the packet should be tossed. |
| 66 | * |
| 67 | */ |
Willem de Bruijn | f4979fc | 2016-07-12 18:18:56 -0400 | [diff] [blame] | 68 | int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap) |
Stephen Hemminger | 43db6d6 | 2008-04-10 01:43:09 -0700 | [diff] [blame] | 69 | { |
| 70 | int err; |
| 71 | struct sk_filter *filter; |
| 72 | |
Mel Gorman | c93bdd0 | 2012-07-31 16:44:19 -0700 | [diff] [blame] | 73 | /* |
| 74 | * If the skb was allocated from pfmemalloc reserves, only |
| 75 | * allow SOCK_MEMALLOC sockets to use it as this socket is |
| 76 | * helping free memory |
| 77 | */ |
| 78 | if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) |
| 79 | return -ENOMEM; |
| 80 | |
Stephen Hemminger | 43db6d6 | 2008-04-10 01:43:09 -0700 | [diff] [blame] | 81 | err = security_sock_rcv_skb(sk, skb); |
| 82 | if (err) |
| 83 | return err; |
| 84 | |
Eric Dumazet | 80f8f10 | 2011-01-18 07:46:52 +0000 | [diff] [blame] | 85 | rcu_read_lock(); |
| 86 | filter = rcu_dereference(sk->sk_filter); |
Stephen Hemminger | 43db6d6 | 2008-04-10 01:43:09 -0700 | [diff] [blame] | 87 | if (filter) { |
Alexei Starovoitov | ff936a0 | 2015-10-07 10:55:41 -0700 | [diff] [blame] | 88 | unsigned int pkt_len = bpf_prog_run_save_cb(filter->prog, skb); |
Willem de Bruijn | f4979fc | 2016-07-12 18:18:56 -0400 | [diff] [blame] | 89 | err = pkt_len ? pskb_trim(skb, max(cap, pkt_len)) : -EPERM; |
Stephen Hemminger | 43db6d6 | 2008-04-10 01:43:09 -0700 | [diff] [blame] | 90 | } |
Eric Dumazet | 80f8f10 | 2011-01-18 07:46:52 +0000 | [diff] [blame] | 91 | rcu_read_unlock(); |
Stephen Hemminger | 43db6d6 | 2008-04-10 01:43:09 -0700 | [diff] [blame] | 92 | |
| 93 | return err; |
| 94 | } |
Willem de Bruijn | f4979fc | 2016-07-12 18:18:56 -0400 | [diff] [blame] | 95 | EXPORT_SYMBOL(sk_filter_trim_cap); |
Stephen Hemminger | 43db6d6 | 2008-04-10 01:43:09 -0700 | [diff] [blame] | 96 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 97 | BPF_CALL_1(__skb_get_pay_offset, struct sk_buff *, skb) |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 98 | { |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 99 | return skb_get_poff(skb); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 100 | } |
| 101 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 102 | BPF_CALL_3(__skb_get_nlattr, struct sk_buff *, skb, u32, a, u32, x) |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 103 | { |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 104 | struct nlattr *nla; |
| 105 | |
| 106 | if (skb_is_nonlinear(skb)) |
| 107 | return 0; |
| 108 | |
Mathias Krause | 05ab8f2 | 2014-04-13 18:23:33 +0200 | [diff] [blame] | 109 | if (skb->len < sizeof(struct nlattr)) |
| 110 | return 0; |
| 111 | |
Daniel Borkmann | 3074383 | 2014-05-01 18:34:19 +0200 | [diff] [blame] | 112 | if (a > skb->len - sizeof(struct nlattr)) |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 113 | return 0; |
| 114 | |
Daniel Borkmann | 3074383 | 2014-05-01 18:34:19 +0200 | [diff] [blame] | 115 | nla = nla_find((struct nlattr *) &skb->data[a], skb->len - a, x); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 116 | if (nla) |
| 117 | return (void *) nla - (void *) skb->data; |
| 118 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | return 0; |
| 120 | } |
| 121 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 122 | BPF_CALL_3(__skb_get_nlattr_nest, struct sk_buff *, skb, u32, a, u32, x) |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 123 | { |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 124 | struct nlattr *nla; |
| 125 | |
| 126 | if (skb_is_nonlinear(skb)) |
| 127 | return 0; |
| 128 | |
Mathias Krause | 05ab8f2 | 2014-04-13 18:23:33 +0200 | [diff] [blame] | 129 | if (skb->len < sizeof(struct nlattr)) |
| 130 | return 0; |
| 131 | |
Daniel Borkmann | 3074383 | 2014-05-01 18:34:19 +0200 | [diff] [blame] | 132 | if (a > skb->len - sizeof(struct nlattr)) |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 133 | return 0; |
| 134 | |
Daniel Borkmann | 3074383 | 2014-05-01 18:34:19 +0200 | [diff] [blame] | 135 | nla = (struct nlattr *) &skb->data[a]; |
| 136 | if (nla->nla_len > skb->len - a) |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 137 | return 0; |
| 138 | |
Daniel Borkmann | 3074383 | 2014-05-01 18:34:19 +0200 | [diff] [blame] | 139 | nla = nla_find_nested(nla, x); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 140 | if (nla) |
| 141 | return (void *) nla - (void *) skb->data; |
| 142 | |
| 143 | return 0; |
| 144 | } |
| 145 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 146 | BPF_CALL_0(__get_raw_cpu_id) |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 147 | { |
| 148 | return raw_smp_processor_id(); |
| 149 | } |
| 150 | |
Daniel Borkmann | 80b48c4 | 2016-06-28 12:18:26 +0200 | [diff] [blame] | 151 | static const struct bpf_func_proto bpf_get_raw_smp_processor_id_proto = { |
| 152 | .func = __get_raw_cpu_id, |
| 153 | .gpl_only = false, |
| 154 | .ret_type = RET_INTEGER, |
| 155 | }; |
| 156 | |
Alexei Starovoitov | 9bac3d6 | 2015-03-13 11:57:42 -0700 | [diff] [blame] | 157 | static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg, |
| 158 | struct bpf_insn *insn_buf) |
| 159 | { |
| 160 | struct bpf_insn *insn = insn_buf; |
| 161 | |
| 162 | switch (skb_field) { |
| 163 | case SKF_AD_MARK: |
| 164 | BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, mark) != 4); |
| 165 | |
| 166 | *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg, |
| 167 | offsetof(struct sk_buff, mark)); |
| 168 | break; |
| 169 | |
| 170 | case SKF_AD_PKTTYPE: |
| 171 | *insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_TYPE_OFFSET()); |
| 172 | *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, PKT_TYPE_MAX); |
| 173 | #ifdef __BIG_ENDIAN_BITFIELD |
| 174 | *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 5); |
| 175 | #endif |
| 176 | break; |
| 177 | |
| 178 | case SKF_AD_QUEUE: |
| 179 | BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, queue_mapping) != 2); |
| 180 | |
| 181 | *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg, |
| 182 | offsetof(struct sk_buff, queue_mapping)); |
| 183 | break; |
Alexei Starovoitov | c249739 | 2015-03-16 18:06:02 -0700 | [diff] [blame] | 184 | |
Alexei Starovoitov | c249739 | 2015-03-16 18:06:02 -0700 | [diff] [blame] | 185 | case SKF_AD_VLAN_TAG: |
| 186 | case SKF_AD_VLAN_TAG_PRESENT: |
| 187 | BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_tci) != 2); |
| 188 | BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000); |
| 189 | |
| 190 | /* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */ |
| 191 | *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg, |
| 192 | offsetof(struct sk_buff, vlan_tci)); |
| 193 | if (skb_field == SKF_AD_VLAN_TAG) { |
| 194 | *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, |
| 195 | ~VLAN_TAG_PRESENT); |
| 196 | } else { |
| 197 | /* dst_reg >>= 12 */ |
| 198 | *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 12); |
| 199 | /* dst_reg &= 1 */ |
| 200 | *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 1); |
| 201 | } |
| 202 | break; |
Alexei Starovoitov | 9bac3d6 | 2015-03-13 11:57:42 -0700 | [diff] [blame] | 203 | } |
| 204 | |
| 205 | return insn - insn_buf; |
| 206 | } |
| 207 | |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 208 | static bool convert_bpf_extensions(struct sock_filter *fp, |
Alexei Starovoitov | 2695fb5 | 2014-07-24 16:38:21 -0700 | [diff] [blame] | 209 | struct bpf_insn **insnp) |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 210 | { |
Alexei Starovoitov | 2695fb5 | 2014-07-24 16:38:21 -0700 | [diff] [blame] | 211 | struct bpf_insn *insn = *insnp; |
Alexei Starovoitov | 9bac3d6 | 2015-03-13 11:57:42 -0700 | [diff] [blame] | 212 | u32 cnt; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 213 | |
| 214 | switch (fp->k) { |
| 215 | case SKF_AD_OFF + SKF_AD_PROTOCOL: |
Daniel Borkmann | 0b8c707 | 2015-03-19 19:38:27 +0100 | [diff] [blame] | 216 | BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, protocol) != 2); |
| 217 | |
| 218 | /* A = *(u16 *) (CTX + offsetof(protocol)) */ |
| 219 | *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX, |
| 220 | offsetof(struct sk_buff, protocol)); |
| 221 | /* A = ntohs(A) [emitting a nop or swap16] */ |
| 222 | *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 223 | break; |
| 224 | |
| 225 | case SKF_AD_OFF + SKF_AD_PKTTYPE: |
Alexei Starovoitov | 9bac3d6 | 2015-03-13 11:57:42 -0700 | [diff] [blame] | 226 | cnt = convert_skb_access(SKF_AD_PKTTYPE, BPF_REG_A, BPF_REG_CTX, insn); |
| 227 | insn += cnt - 1; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 228 | break; |
| 229 | |
| 230 | case SKF_AD_OFF + SKF_AD_IFINDEX: |
| 231 | case SKF_AD_OFF + SKF_AD_HATYPE: |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 232 | BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, ifindex) != 4); |
| 233 | BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, type) != 2); |
| 234 | |
Daniel Borkmann | f035a51 | 2016-09-09 02:45:29 +0200 | [diff] [blame] | 235 | *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev), |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 236 | BPF_REG_TMP, BPF_REG_CTX, |
| 237 | offsetof(struct sk_buff, dev)); |
| 238 | /* if (tmp != 0) goto pc + 1 */ |
| 239 | *insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_TMP, 0, 1); |
| 240 | *insn++ = BPF_EXIT_INSN(); |
| 241 | if (fp->k == SKF_AD_OFF + SKF_AD_IFINDEX) |
| 242 | *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_TMP, |
| 243 | offsetof(struct net_device, ifindex)); |
| 244 | else |
| 245 | *insn = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_TMP, |
| 246 | offsetof(struct net_device, type)); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 247 | break; |
| 248 | |
| 249 | case SKF_AD_OFF + SKF_AD_MARK: |
Alexei Starovoitov | 9bac3d6 | 2015-03-13 11:57:42 -0700 | [diff] [blame] | 250 | cnt = convert_skb_access(SKF_AD_MARK, BPF_REG_A, BPF_REG_CTX, insn); |
| 251 | insn += cnt - 1; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 252 | break; |
| 253 | |
| 254 | case SKF_AD_OFF + SKF_AD_RXHASH: |
| 255 | BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, hash) != 4); |
| 256 | |
Alexei Starovoitov | 9739eef | 2014-05-08 14:10:51 -0700 | [diff] [blame] | 257 | *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, |
| 258 | offsetof(struct sk_buff, hash)); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 259 | break; |
| 260 | |
| 261 | case SKF_AD_OFF + SKF_AD_QUEUE: |
Alexei Starovoitov | 9bac3d6 | 2015-03-13 11:57:42 -0700 | [diff] [blame] | 262 | cnt = convert_skb_access(SKF_AD_QUEUE, BPF_REG_A, BPF_REG_CTX, insn); |
| 263 | insn += cnt - 1; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 264 | break; |
| 265 | |
| 266 | case SKF_AD_OFF + SKF_AD_VLAN_TAG: |
Alexei Starovoitov | c249739 | 2015-03-16 18:06:02 -0700 | [diff] [blame] | 267 | cnt = convert_skb_access(SKF_AD_VLAN_TAG, |
| 268 | BPF_REG_A, BPF_REG_CTX, insn); |
| 269 | insn += cnt - 1; |
| 270 | break; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 271 | |
Alexei Starovoitov | c249739 | 2015-03-16 18:06:02 -0700 | [diff] [blame] | 272 | case SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT: |
| 273 | cnt = convert_skb_access(SKF_AD_VLAN_TAG_PRESENT, |
| 274 | BPF_REG_A, BPF_REG_CTX, insn); |
| 275 | insn += cnt - 1; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 276 | break; |
| 277 | |
Michal Sekletar | 27cd545 | 2015-03-24 14:48:41 +0100 | [diff] [blame] | 278 | case SKF_AD_OFF + SKF_AD_VLAN_TPID: |
| 279 | BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_proto) != 2); |
| 280 | |
| 281 | /* A = *(u16 *) (CTX + offsetof(vlan_proto)) */ |
| 282 | *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX, |
| 283 | offsetof(struct sk_buff, vlan_proto)); |
| 284 | /* A = ntohs(A) [emitting a nop or swap16] */ |
| 285 | *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16); |
| 286 | break; |
| 287 | |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 288 | case SKF_AD_OFF + SKF_AD_PAY_OFFSET: |
| 289 | case SKF_AD_OFF + SKF_AD_NLATTR: |
| 290 | case SKF_AD_OFF + SKF_AD_NLATTR_NEST: |
| 291 | case SKF_AD_OFF + SKF_AD_CPU: |
Chema Gonzalez | 4cd3675 | 2014-04-21 09:21:24 -0700 | [diff] [blame] | 292 | case SKF_AD_OFF + SKF_AD_RANDOM: |
Alexei Starovoitov | e430f34 | 2014-06-06 14:46:06 -0700 | [diff] [blame] | 293 | /* arg1 = CTX */ |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 294 | *insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 295 | /* arg2 = A */ |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 296 | *insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_A); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 297 | /* arg3 = X */ |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 298 | *insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_X); |
Alexei Starovoitov | e430f34 | 2014-06-06 14:46:06 -0700 | [diff] [blame] | 299 | /* Emit call(arg1=CTX, arg2=A, arg3=X) */ |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 300 | switch (fp->k) { |
| 301 | case SKF_AD_OFF + SKF_AD_PAY_OFFSET: |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 302 | *insn = BPF_EMIT_CALL(__skb_get_pay_offset); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 303 | break; |
| 304 | case SKF_AD_OFF + SKF_AD_NLATTR: |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 305 | *insn = BPF_EMIT_CALL(__skb_get_nlattr); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 306 | break; |
| 307 | case SKF_AD_OFF + SKF_AD_NLATTR_NEST: |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 308 | *insn = BPF_EMIT_CALL(__skb_get_nlattr_nest); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 309 | break; |
| 310 | case SKF_AD_OFF + SKF_AD_CPU: |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 311 | *insn = BPF_EMIT_CALL(__get_raw_cpu_id); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 312 | break; |
Chema Gonzalez | 4cd3675 | 2014-04-21 09:21:24 -0700 | [diff] [blame] | 313 | case SKF_AD_OFF + SKF_AD_RANDOM: |
Daniel Borkmann | 3ad0040 | 2015-10-08 01:20:39 +0200 | [diff] [blame] | 314 | *insn = BPF_EMIT_CALL(bpf_user_rnd_u32); |
| 315 | bpf_user_rnd_init_once(); |
Chema Gonzalez | 4cd3675 | 2014-04-21 09:21:24 -0700 | [diff] [blame] | 316 | break; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 317 | } |
| 318 | break; |
| 319 | |
| 320 | case SKF_AD_OFF + SKF_AD_ALU_XOR_X: |
Alexei Starovoitov | 9739eef | 2014-05-08 14:10:51 -0700 | [diff] [blame] | 321 | /* A ^= X */ |
| 322 | *insn = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_X); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 323 | break; |
| 324 | |
| 325 | default: |
| 326 | /* This is just a dummy call to avoid letting the compiler |
| 327 | * evict __bpf_call_base() as an optimization. Placed here |
| 328 | * where no-one bothers. |
| 329 | */ |
| 330 | BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0); |
| 331 | return false; |
| 332 | } |
| 333 | |
| 334 | *insnp = insn; |
| 335 | return true; |
| 336 | } |
| 337 | |
| 338 | /** |
Alexei Starovoitov | 8fb575c | 2014-07-30 20:34:15 -0700 | [diff] [blame] | 339 | * bpf_convert_filter - convert filter program |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 340 | * @prog: the user passed filter program |
| 341 | * @len: the length of the user passed filter program |
| 342 | * @new_prog: buffer where converted program will be stored |
| 343 | * @new_len: pointer to store length of converted program |
| 344 | * |
| 345 | * Remap 'sock_filter' style BPF instruction set to 'sock_filter_ext' style. |
| 346 | * Conversion workflow: |
| 347 | * |
| 348 | * 1) First pass for calculating the new program length: |
Alexei Starovoitov | 8fb575c | 2014-07-30 20:34:15 -0700 | [diff] [blame] | 349 | * bpf_convert_filter(old_prog, old_len, NULL, &new_len) |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 350 | * |
| 351 | * 2) 2nd pass to remap in two passes: 1st pass finds new |
| 352 | * jump offsets, 2nd pass remapping: |
Alexei Starovoitov | 2695fb5 | 2014-07-24 16:38:21 -0700 | [diff] [blame] | 353 | * new_prog = kmalloc(sizeof(struct bpf_insn) * new_len); |
Alexei Starovoitov | 8fb575c | 2014-07-30 20:34:15 -0700 | [diff] [blame] | 354 | * bpf_convert_filter(old_prog, old_len, new_prog, &new_len); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 355 | */ |
Nicolas Schichan | d9e12f4 | 2015-05-06 16:12:28 +0200 | [diff] [blame] | 356 | static int bpf_convert_filter(struct sock_filter *prog, int len, |
| 357 | struct bpf_insn *new_prog, int *new_len) |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 358 | { |
| 359 | int new_flen = 0, pass = 0, target, i; |
Alexei Starovoitov | 2695fb5 | 2014-07-24 16:38:21 -0700 | [diff] [blame] | 360 | struct bpf_insn *new_insn; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 361 | struct sock_filter *fp; |
| 362 | int *addrs = NULL; |
| 363 | u8 bpf_src; |
| 364 | |
| 365 | BUILD_BUG_ON(BPF_MEMWORDS * sizeof(u32) > MAX_BPF_STACK); |
Daniel Borkmann | 3074383 | 2014-05-01 18:34:19 +0200 | [diff] [blame] | 366 | BUILD_BUG_ON(BPF_REG_FP + 1 != MAX_BPF_REG); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 367 | |
Kees Cook | 6f9a093 | 2014-06-18 15:34:57 -0700 | [diff] [blame] | 368 | if (len <= 0 || len > BPF_MAXINSNS) |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 369 | return -EINVAL; |
| 370 | |
| 371 | if (new_prog) { |
Daniel Borkmann | 658da93 | 2015-05-06 16:12:29 +0200 | [diff] [blame] | 372 | addrs = kcalloc(len, sizeof(*addrs), |
| 373 | GFP_KERNEL | __GFP_NOWARN); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 374 | if (!addrs) |
| 375 | return -ENOMEM; |
| 376 | } |
| 377 | |
| 378 | do_pass: |
| 379 | new_insn = new_prog; |
| 380 | fp = prog; |
| 381 | |
Daniel Borkmann | 8b614ae | 2015-12-17 23:51:54 +0100 | [diff] [blame] | 382 | /* Classic BPF related prologue emission. */ |
| 383 | if (new_insn) { |
| 384 | /* Classic BPF expects A and X to be reset first. These need |
| 385 | * to be guaranteed to be the first two instructions. |
| 386 | */ |
| 387 | *new_insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_A, BPF_REG_A); |
| 388 | *new_insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_X, BPF_REG_X); |
| 389 | |
| 390 | /* All programs must keep CTX in callee saved BPF_REG_CTX. |
| 391 | * In eBPF case it's done by the compiler, here we need to |
| 392 | * do this ourself. Initial CTX is present in BPF_REG_ARG1. |
| 393 | */ |
| 394 | *new_insn++ = BPF_MOV64_REG(BPF_REG_CTX, BPF_REG_ARG1); |
| 395 | } else { |
| 396 | new_insn += 3; |
| 397 | } |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 398 | |
| 399 | for (i = 0; i < len; fp++, i++) { |
Alexei Starovoitov | 2695fb5 | 2014-07-24 16:38:21 -0700 | [diff] [blame] | 400 | struct bpf_insn tmp_insns[6] = { }; |
| 401 | struct bpf_insn *insn = tmp_insns; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 402 | |
| 403 | if (addrs) |
| 404 | addrs[i] = new_insn - new_prog; |
| 405 | |
| 406 | switch (fp->code) { |
| 407 | /* All arithmetic insns and skb loads map as-is. */ |
| 408 | case BPF_ALU | BPF_ADD | BPF_X: |
| 409 | case BPF_ALU | BPF_ADD | BPF_K: |
| 410 | case BPF_ALU | BPF_SUB | BPF_X: |
| 411 | case BPF_ALU | BPF_SUB | BPF_K: |
| 412 | case BPF_ALU | BPF_AND | BPF_X: |
| 413 | case BPF_ALU | BPF_AND | BPF_K: |
| 414 | case BPF_ALU | BPF_OR | BPF_X: |
| 415 | case BPF_ALU | BPF_OR | BPF_K: |
| 416 | case BPF_ALU | BPF_LSH | BPF_X: |
| 417 | case BPF_ALU | BPF_LSH | BPF_K: |
| 418 | case BPF_ALU | BPF_RSH | BPF_X: |
| 419 | case BPF_ALU | BPF_RSH | BPF_K: |
| 420 | case BPF_ALU | BPF_XOR | BPF_X: |
| 421 | case BPF_ALU | BPF_XOR | BPF_K: |
| 422 | case BPF_ALU | BPF_MUL | BPF_X: |
| 423 | case BPF_ALU | BPF_MUL | BPF_K: |
| 424 | case BPF_ALU | BPF_DIV | BPF_X: |
| 425 | case BPF_ALU | BPF_DIV | BPF_K: |
| 426 | case BPF_ALU | BPF_MOD | BPF_X: |
| 427 | case BPF_ALU | BPF_MOD | BPF_K: |
| 428 | case BPF_ALU | BPF_NEG: |
| 429 | case BPF_LD | BPF_ABS | BPF_W: |
| 430 | case BPF_LD | BPF_ABS | BPF_H: |
| 431 | case BPF_LD | BPF_ABS | BPF_B: |
| 432 | case BPF_LD | BPF_IND | BPF_W: |
| 433 | case BPF_LD | BPF_IND | BPF_H: |
| 434 | case BPF_LD | BPF_IND | BPF_B: |
| 435 | /* Check for overloaded BPF extension and |
| 436 | * directly convert it if found, otherwise |
| 437 | * just move on with mapping. |
| 438 | */ |
| 439 | if (BPF_CLASS(fp->code) == BPF_LD && |
| 440 | BPF_MODE(fp->code) == BPF_ABS && |
| 441 | convert_bpf_extensions(fp, &insn)) |
| 442 | break; |
| 443 | |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 444 | *insn = BPF_RAW_INSN(fp->code, BPF_REG_A, BPF_REG_X, 0, fp->k); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 445 | break; |
| 446 | |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 447 | /* Jump transformation cannot use BPF block macros |
| 448 | * everywhere as offset calculation and target updates |
| 449 | * require a bit more work than the rest, i.e. jump |
| 450 | * opcodes map as-is, but offsets need adjustment. |
| 451 | */ |
| 452 | |
| 453 | #define BPF_EMIT_JMP \ |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 454 | do { \ |
| 455 | if (target >= len || target < 0) \ |
| 456 | goto err; \ |
| 457 | insn->off = addrs ? addrs[target] - addrs[i] - 1 : 0; \ |
| 458 | /* Adjust pc relative offset for 2nd or 3rd insn. */ \ |
| 459 | insn->off -= insn - tmp_insns; \ |
| 460 | } while (0) |
| 461 | |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 462 | case BPF_JMP | BPF_JA: |
| 463 | target = i + fp->k + 1; |
| 464 | insn->code = fp->code; |
| 465 | BPF_EMIT_JMP; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 466 | break; |
| 467 | |
| 468 | case BPF_JMP | BPF_JEQ | BPF_K: |
| 469 | case BPF_JMP | BPF_JEQ | BPF_X: |
| 470 | case BPF_JMP | BPF_JSET | BPF_K: |
| 471 | case BPF_JMP | BPF_JSET | BPF_X: |
| 472 | case BPF_JMP | BPF_JGT | BPF_K: |
| 473 | case BPF_JMP | BPF_JGT | BPF_X: |
| 474 | case BPF_JMP | BPF_JGE | BPF_K: |
| 475 | case BPF_JMP | BPF_JGE | BPF_X: |
| 476 | if (BPF_SRC(fp->code) == BPF_K && (int) fp->k < 0) { |
| 477 | /* BPF immediates are signed, zero extend |
| 478 | * immediate into tmp register and use it |
| 479 | * in compare insn. |
| 480 | */ |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 481 | *insn++ = BPF_MOV32_IMM(BPF_REG_TMP, fp->k); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 482 | |
Alexei Starovoitov | e430f34 | 2014-06-06 14:46:06 -0700 | [diff] [blame] | 483 | insn->dst_reg = BPF_REG_A; |
| 484 | insn->src_reg = BPF_REG_TMP; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 485 | bpf_src = BPF_X; |
| 486 | } else { |
Alexei Starovoitov | e430f34 | 2014-06-06 14:46:06 -0700 | [diff] [blame] | 487 | insn->dst_reg = BPF_REG_A; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 488 | insn->imm = fp->k; |
| 489 | bpf_src = BPF_SRC(fp->code); |
Tycho Andersen | 19539ce | 2015-09-10 18:25:07 -0600 | [diff] [blame] | 490 | insn->src_reg = bpf_src == BPF_X ? BPF_REG_X : 0; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 491 | } |
| 492 | |
| 493 | /* Common case where 'jump_false' is next insn. */ |
| 494 | if (fp->jf == 0) { |
| 495 | insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src; |
| 496 | target = i + fp->jt + 1; |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 497 | BPF_EMIT_JMP; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 498 | break; |
| 499 | } |
| 500 | |
| 501 | /* Convert JEQ into JNE when 'jump_true' is next insn. */ |
| 502 | if (fp->jt == 0 && BPF_OP(fp->code) == BPF_JEQ) { |
| 503 | insn->code = BPF_JMP | BPF_JNE | bpf_src; |
| 504 | target = i + fp->jf + 1; |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 505 | BPF_EMIT_JMP; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 506 | break; |
| 507 | } |
| 508 | |
| 509 | /* Other jumps are mapped into two insns: Jxx and JA. */ |
| 510 | target = i + fp->jt + 1; |
| 511 | insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src; |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 512 | BPF_EMIT_JMP; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 513 | insn++; |
| 514 | |
| 515 | insn->code = BPF_JMP | BPF_JA; |
| 516 | target = i + fp->jf + 1; |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 517 | BPF_EMIT_JMP; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 518 | break; |
| 519 | |
| 520 | /* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */ |
| 521 | case BPF_LDX | BPF_MSH | BPF_B: |
Alexei Starovoitov | 9739eef | 2014-05-08 14:10:51 -0700 | [diff] [blame] | 522 | /* tmp = A */ |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 523 | *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_A); |
David S. Miller | 1268e25 | 2014-05-13 13:13:33 -0400 | [diff] [blame] | 524 | /* A = BPF_R0 = *(u8 *) (skb->data + K) */ |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 525 | *insn++ = BPF_LD_ABS(BPF_B, fp->k); |
Alexei Starovoitov | 9739eef | 2014-05-08 14:10:51 -0700 | [diff] [blame] | 526 | /* A &= 0xf */ |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 527 | *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_A, 0xf); |
Alexei Starovoitov | 9739eef | 2014-05-08 14:10:51 -0700 | [diff] [blame] | 528 | /* A <<= 2 */ |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 529 | *insn++ = BPF_ALU32_IMM(BPF_LSH, BPF_REG_A, 2); |
Alexei Starovoitov | 9739eef | 2014-05-08 14:10:51 -0700 | [diff] [blame] | 530 | /* X = A */ |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 531 | *insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A); |
Alexei Starovoitov | 9739eef | 2014-05-08 14:10:51 -0700 | [diff] [blame] | 532 | /* A = tmp */ |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 533 | *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_TMP); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 534 | break; |
| 535 | |
Daniel Borkmann | 6205b9c | 2016-02-19 23:05:27 +0100 | [diff] [blame] | 536 | /* RET_K is remaped into 2 insns. RET_A case doesn't need an |
| 537 | * extra mov as BPF_REG_0 is already mapped into BPF_REG_A. |
| 538 | */ |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 539 | case BPF_RET | BPF_A: |
| 540 | case BPF_RET | BPF_K: |
Daniel Borkmann | 6205b9c | 2016-02-19 23:05:27 +0100 | [diff] [blame] | 541 | if (BPF_RVAL(fp->code) == BPF_K) |
| 542 | *insn++ = BPF_MOV32_RAW(BPF_K, BPF_REG_0, |
| 543 | 0, fp->k); |
Alexei Starovoitov | 9739eef | 2014-05-08 14:10:51 -0700 | [diff] [blame] | 544 | *insn = BPF_EXIT_INSN(); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 545 | break; |
| 546 | |
| 547 | /* Store to stack. */ |
| 548 | case BPF_ST: |
| 549 | case BPF_STX: |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 550 | *insn = BPF_STX_MEM(BPF_W, BPF_REG_FP, BPF_CLASS(fp->code) == |
| 551 | BPF_ST ? BPF_REG_A : BPF_REG_X, |
| 552 | -(BPF_MEMWORDS - fp->k) * 4); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 553 | break; |
| 554 | |
| 555 | /* Load from stack. */ |
| 556 | case BPF_LD | BPF_MEM: |
| 557 | case BPF_LDX | BPF_MEM: |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 558 | *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ? |
| 559 | BPF_REG_A : BPF_REG_X, BPF_REG_FP, |
| 560 | -(BPF_MEMWORDS - fp->k) * 4); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 561 | break; |
| 562 | |
| 563 | /* A = K or X = K */ |
| 564 | case BPF_LD | BPF_IMM: |
| 565 | case BPF_LDX | BPF_IMM: |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 566 | *insn = BPF_MOV32_IMM(BPF_CLASS(fp->code) == BPF_LD ? |
| 567 | BPF_REG_A : BPF_REG_X, fp->k); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 568 | break; |
| 569 | |
| 570 | /* X = A */ |
| 571 | case BPF_MISC | BPF_TAX: |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 572 | *insn = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 573 | break; |
| 574 | |
| 575 | /* A = X */ |
| 576 | case BPF_MISC | BPF_TXA: |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 577 | *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_X); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 578 | break; |
| 579 | |
| 580 | /* A = skb->len or X = skb->len */ |
| 581 | case BPF_LD | BPF_W | BPF_LEN: |
| 582 | case BPF_LDX | BPF_W | BPF_LEN: |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 583 | *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ? |
| 584 | BPF_REG_A : BPF_REG_X, BPF_REG_CTX, |
| 585 | offsetof(struct sk_buff, len)); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 586 | break; |
| 587 | |
Daniel Borkmann | f8f6d67 | 2014-05-29 10:22:51 +0200 | [diff] [blame] | 588 | /* Access seccomp_data fields. */ |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 589 | case BPF_LDX | BPF_ABS | BPF_W: |
Alexei Starovoitov | 9739eef | 2014-05-08 14:10:51 -0700 | [diff] [blame] | 590 | /* A = *(u32 *) (ctx + K) */ |
| 591 | *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, fp->k); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 592 | break; |
| 593 | |
Stephen Hemminger | ca9f1fd | 2015-02-14 13:47:54 -0500 | [diff] [blame] | 594 | /* Unknown instruction. */ |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 595 | default: |
| 596 | goto err; |
| 597 | } |
| 598 | |
| 599 | insn++; |
| 600 | if (new_prog) |
| 601 | memcpy(new_insn, tmp_insns, |
| 602 | sizeof(*insn) * (insn - tmp_insns)); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 603 | new_insn += insn - tmp_insns; |
| 604 | } |
| 605 | |
| 606 | if (!new_prog) { |
| 607 | /* Only calculating new length. */ |
| 608 | *new_len = new_insn - new_prog; |
| 609 | return 0; |
| 610 | } |
| 611 | |
| 612 | pass++; |
| 613 | if (new_flen != new_insn - new_prog) { |
| 614 | new_flen = new_insn - new_prog; |
| 615 | if (pass > 2) |
| 616 | goto err; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 617 | goto do_pass; |
| 618 | } |
| 619 | |
| 620 | kfree(addrs); |
| 621 | BUG_ON(*new_len != new_flen); |
| 622 | return 0; |
| 623 | err: |
| 624 | kfree(addrs); |
| 625 | return -EINVAL; |
| 626 | } |
| 627 | |
| 628 | /* Security: |
| 629 | * |
Eric Dumazet | 2d5311e | 2010-12-01 20:46:24 +0000 | [diff] [blame] | 630 | * As we dont want to clear mem[] array for each packet going through |
Li RongQing | 8ea6e34 | 2014-10-10 13:56:51 +0800 | [diff] [blame] | 631 | * __bpf_prog_run(), we check that filter loaded by user never try to read |
Eric Dumazet | 2d5311e | 2010-12-01 20:46:24 +0000 | [diff] [blame] | 632 | * a cell if not previously written, and we check all branches to be sure |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 633 | * a malicious user doesn't try to abuse us. |
Eric Dumazet | 2d5311e | 2010-12-01 20:46:24 +0000 | [diff] [blame] | 634 | */ |
Eric Dumazet | ec31a05 | 2014-07-12 15:49:16 +0200 | [diff] [blame] | 635 | static int check_load_and_stores(const struct sock_filter *filter, int flen) |
Eric Dumazet | 2d5311e | 2010-12-01 20:46:24 +0000 | [diff] [blame] | 636 | { |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 637 | u16 *masks, memvalid = 0; /* One bit per cell, 16 cells */ |
Eric Dumazet | 2d5311e | 2010-12-01 20:46:24 +0000 | [diff] [blame] | 638 | int pc, ret = 0; |
| 639 | |
| 640 | BUILD_BUG_ON(BPF_MEMWORDS > 16); |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 641 | |
Tobias Klauser | 99e72a0 | 2014-06-24 15:33:22 +0200 | [diff] [blame] | 642 | masks = kmalloc_array(flen, sizeof(*masks), GFP_KERNEL); |
Eric Dumazet | 2d5311e | 2010-12-01 20:46:24 +0000 | [diff] [blame] | 643 | if (!masks) |
| 644 | return -ENOMEM; |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 645 | |
Eric Dumazet | 2d5311e | 2010-12-01 20:46:24 +0000 | [diff] [blame] | 646 | memset(masks, 0xff, flen * sizeof(*masks)); |
| 647 | |
| 648 | for (pc = 0; pc < flen; pc++) { |
| 649 | memvalid &= masks[pc]; |
| 650 | |
| 651 | switch (filter[pc].code) { |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 652 | case BPF_ST: |
| 653 | case BPF_STX: |
Eric Dumazet | 2d5311e | 2010-12-01 20:46:24 +0000 | [diff] [blame] | 654 | memvalid |= (1 << filter[pc].k); |
| 655 | break; |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 656 | case BPF_LD | BPF_MEM: |
| 657 | case BPF_LDX | BPF_MEM: |
Eric Dumazet | 2d5311e | 2010-12-01 20:46:24 +0000 | [diff] [blame] | 658 | if (!(memvalid & (1 << filter[pc].k))) { |
| 659 | ret = -EINVAL; |
| 660 | goto error; |
| 661 | } |
| 662 | break; |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 663 | case BPF_JMP | BPF_JA: |
| 664 | /* A jump must set masks on target */ |
Eric Dumazet | 2d5311e | 2010-12-01 20:46:24 +0000 | [diff] [blame] | 665 | masks[pc + 1 + filter[pc].k] &= memvalid; |
| 666 | memvalid = ~0; |
| 667 | break; |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 668 | case BPF_JMP | BPF_JEQ | BPF_K: |
| 669 | case BPF_JMP | BPF_JEQ | BPF_X: |
| 670 | case BPF_JMP | BPF_JGE | BPF_K: |
| 671 | case BPF_JMP | BPF_JGE | BPF_X: |
| 672 | case BPF_JMP | BPF_JGT | BPF_K: |
| 673 | case BPF_JMP | BPF_JGT | BPF_X: |
| 674 | case BPF_JMP | BPF_JSET | BPF_K: |
| 675 | case BPF_JMP | BPF_JSET | BPF_X: |
| 676 | /* A jump must set masks on targets */ |
Eric Dumazet | 2d5311e | 2010-12-01 20:46:24 +0000 | [diff] [blame] | 677 | masks[pc + 1 + filter[pc].jt] &= memvalid; |
| 678 | masks[pc + 1 + filter[pc].jf] &= memvalid; |
| 679 | memvalid = ~0; |
| 680 | break; |
| 681 | } |
| 682 | } |
| 683 | error: |
| 684 | kfree(masks); |
| 685 | return ret; |
| 686 | } |
| 687 | |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 688 | static bool chk_code_allowed(u16 code_to_probe) |
| 689 | { |
| 690 | static const bool codes[] = { |
| 691 | /* 32 bit ALU operations */ |
| 692 | [BPF_ALU | BPF_ADD | BPF_K] = true, |
| 693 | [BPF_ALU | BPF_ADD | BPF_X] = true, |
| 694 | [BPF_ALU | BPF_SUB | BPF_K] = true, |
| 695 | [BPF_ALU | BPF_SUB | BPF_X] = true, |
| 696 | [BPF_ALU | BPF_MUL | BPF_K] = true, |
| 697 | [BPF_ALU | BPF_MUL | BPF_X] = true, |
| 698 | [BPF_ALU | BPF_DIV | BPF_K] = true, |
| 699 | [BPF_ALU | BPF_DIV | BPF_X] = true, |
| 700 | [BPF_ALU | BPF_MOD | BPF_K] = true, |
| 701 | [BPF_ALU | BPF_MOD | BPF_X] = true, |
| 702 | [BPF_ALU | BPF_AND | BPF_K] = true, |
| 703 | [BPF_ALU | BPF_AND | BPF_X] = true, |
| 704 | [BPF_ALU | BPF_OR | BPF_K] = true, |
| 705 | [BPF_ALU | BPF_OR | BPF_X] = true, |
| 706 | [BPF_ALU | BPF_XOR | BPF_K] = true, |
| 707 | [BPF_ALU | BPF_XOR | BPF_X] = true, |
| 708 | [BPF_ALU | BPF_LSH | BPF_K] = true, |
| 709 | [BPF_ALU | BPF_LSH | BPF_X] = true, |
| 710 | [BPF_ALU | BPF_RSH | BPF_K] = true, |
| 711 | [BPF_ALU | BPF_RSH | BPF_X] = true, |
| 712 | [BPF_ALU | BPF_NEG] = true, |
| 713 | /* Load instructions */ |
| 714 | [BPF_LD | BPF_W | BPF_ABS] = true, |
| 715 | [BPF_LD | BPF_H | BPF_ABS] = true, |
| 716 | [BPF_LD | BPF_B | BPF_ABS] = true, |
| 717 | [BPF_LD | BPF_W | BPF_LEN] = true, |
| 718 | [BPF_LD | BPF_W | BPF_IND] = true, |
| 719 | [BPF_LD | BPF_H | BPF_IND] = true, |
| 720 | [BPF_LD | BPF_B | BPF_IND] = true, |
| 721 | [BPF_LD | BPF_IMM] = true, |
| 722 | [BPF_LD | BPF_MEM] = true, |
| 723 | [BPF_LDX | BPF_W | BPF_LEN] = true, |
| 724 | [BPF_LDX | BPF_B | BPF_MSH] = true, |
| 725 | [BPF_LDX | BPF_IMM] = true, |
| 726 | [BPF_LDX | BPF_MEM] = true, |
| 727 | /* Store instructions */ |
| 728 | [BPF_ST] = true, |
| 729 | [BPF_STX] = true, |
| 730 | /* Misc instructions */ |
| 731 | [BPF_MISC | BPF_TAX] = true, |
| 732 | [BPF_MISC | BPF_TXA] = true, |
| 733 | /* Return instructions */ |
| 734 | [BPF_RET | BPF_K] = true, |
| 735 | [BPF_RET | BPF_A] = true, |
| 736 | /* Jump instructions */ |
| 737 | [BPF_JMP | BPF_JA] = true, |
| 738 | [BPF_JMP | BPF_JEQ | BPF_K] = true, |
| 739 | [BPF_JMP | BPF_JEQ | BPF_X] = true, |
| 740 | [BPF_JMP | BPF_JGE | BPF_K] = true, |
| 741 | [BPF_JMP | BPF_JGE | BPF_X] = true, |
| 742 | [BPF_JMP | BPF_JGT | BPF_K] = true, |
| 743 | [BPF_JMP | BPF_JGT | BPF_X] = true, |
| 744 | [BPF_JMP | BPF_JSET | BPF_K] = true, |
| 745 | [BPF_JMP | BPF_JSET | BPF_X] = true, |
| 746 | }; |
| 747 | |
| 748 | if (code_to_probe >= ARRAY_SIZE(codes)) |
| 749 | return false; |
| 750 | |
| 751 | return codes[code_to_probe]; |
| 752 | } |
| 753 | |
Daniel Borkmann | f7bd9e3 | 2016-06-10 21:19:07 +0200 | [diff] [blame] | 754 | static bool bpf_check_basics_ok(const struct sock_filter *filter, |
| 755 | unsigned int flen) |
| 756 | { |
| 757 | if (filter == NULL) |
| 758 | return false; |
| 759 | if (flen == 0 || flen > BPF_MAXINSNS) |
| 760 | return false; |
| 761 | |
| 762 | return true; |
| 763 | } |
| 764 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 765 | /** |
Alexei Starovoitov | 4df95ff | 2014-07-30 20:34:14 -0700 | [diff] [blame] | 766 | * bpf_check_classic - verify socket filter code |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 767 | * @filter: filter to verify |
| 768 | * @flen: length of filter |
| 769 | * |
| 770 | * Check the user's filter code. If we let some ugly |
| 771 | * filter code slip through kaboom! The filter must contain |
Kris Katterjohn | 9369986 | 2006-01-04 13:58:36 -0800 | [diff] [blame] | 772 | * no references or jumps that are out of range, no illegal |
| 773 | * instructions, and must end with a RET instruction. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 774 | * |
Kris Katterjohn | 7b11f69 | 2006-01-13 14:33:06 -0800 | [diff] [blame] | 775 | * All jumps are forward as they are not signed. |
| 776 | * |
| 777 | * Returns 0 if the rule set is legal or -EINVAL if not. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 778 | */ |
Nicolas Schichan | d9e12f4 | 2015-05-06 16:12:28 +0200 | [diff] [blame] | 779 | static int bpf_check_classic(const struct sock_filter *filter, |
| 780 | unsigned int flen) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 781 | { |
Daniel Borkmann | aa1113d | 2012-12-28 10:50:17 +0000 | [diff] [blame] | 782 | bool anc_found; |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 783 | int pc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 784 | |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 785 | /* Check the filter code now */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 786 | for (pc = 0; pc < flen; pc++) { |
Eric Dumazet | ec31a05 | 2014-07-12 15:49:16 +0200 | [diff] [blame] | 787 | const struct sock_filter *ftest = &filter[pc]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 788 | |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 789 | /* May we actually operate on this code? */ |
| 790 | if (!chk_code_allowed(ftest->code)) |
Tetsuo Handa | cba328f | 2010-11-16 15:19:51 +0000 | [diff] [blame] | 791 | return -EINVAL; |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 792 | |
Kris Katterjohn | 9369986 | 2006-01-04 13:58:36 -0800 | [diff] [blame] | 793 | /* Some instructions need special checks */ |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 794 | switch (ftest->code) { |
| 795 | case BPF_ALU | BPF_DIV | BPF_K: |
| 796 | case BPF_ALU | BPF_MOD | BPF_K: |
| 797 | /* Check for division by zero */ |
Eric Dumazet | b6069a9 | 2012-09-07 22:03:35 +0000 | [diff] [blame] | 798 | if (ftest->k == 0) |
| 799 | return -EINVAL; |
| 800 | break; |
Rabin Vincent | 229394e | 2016-01-12 20:17:08 +0100 | [diff] [blame] | 801 | case BPF_ALU | BPF_LSH | BPF_K: |
| 802 | case BPF_ALU | BPF_RSH | BPF_K: |
| 803 | if (ftest->k >= 32) |
| 804 | return -EINVAL; |
| 805 | break; |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 806 | case BPF_LD | BPF_MEM: |
| 807 | case BPF_LDX | BPF_MEM: |
| 808 | case BPF_ST: |
| 809 | case BPF_STX: |
| 810 | /* Check for invalid memory addresses */ |
Kris Katterjohn | 9369986 | 2006-01-04 13:58:36 -0800 | [diff] [blame] | 811 | if (ftest->k >= BPF_MEMWORDS) |
| 812 | return -EINVAL; |
Hagen Paul Pfeifer | 01f2f3f | 2010-06-19 17:05:36 +0000 | [diff] [blame] | 813 | break; |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 814 | case BPF_JMP | BPF_JA: |
| 815 | /* Note, the large ftest->k might cause loops. |
Kris Katterjohn | 9369986 | 2006-01-04 13:58:36 -0800 | [diff] [blame] | 816 | * Compare this with conditional jumps below, |
| 817 | * where offsets are limited. --ANK (981016) |
| 818 | */ |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 819 | if (ftest->k >= (unsigned int)(flen - pc - 1)) |
Kris Katterjohn | 9369986 | 2006-01-04 13:58:36 -0800 | [diff] [blame] | 820 | return -EINVAL; |
| 821 | break; |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 822 | case BPF_JMP | BPF_JEQ | BPF_K: |
| 823 | case BPF_JMP | BPF_JEQ | BPF_X: |
| 824 | case BPF_JMP | BPF_JGE | BPF_K: |
| 825 | case BPF_JMP | BPF_JGE | BPF_X: |
| 826 | case BPF_JMP | BPF_JGT | BPF_K: |
| 827 | case BPF_JMP | BPF_JGT | BPF_X: |
| 828 | case BPF_JMP | BPF_JSET | BPF_K: |
| 829 | case BPF_JMP | BPF_JSET | BPF_X: |
| 830 | /* Both conditionals must be safe */ |
Hagen Paul Pfeifer | 01f2f3f | 2010-06-19 17:05:36 +0000 | [diff] [blame] | 831 | if (pc + ftest->jt + 1 >= flen || |
| 832 | pc + ftest->jf + 1 >= flen) |
| 833 | return -EINVAL; |
Tetsuo Handa | cba328f | 2010-11-16 15:19:51 +0000 | [diff] [blame] | 834 | break; |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 835 | case BPF_LD | BPF_W | BPF_ABS: |
| 836 | case BPF_LD | BPF_H | BPF_ABS: |
| 837 | case BPF_LD | BPF_B | BPF_ABS: |
Daniel Borkmann | aa1113d | 2012-12-28 10:50:17 +0000 | [diff] [blame] | 838 | anc_found = false; |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 839 | if (bpf_anc_helper(ftest) & BPF_ANC) |
| 840 | anc_found = true; |
| 841 | /* Ancillary operation unknown or unsupported */ |
Daniel Borkmann | aa1113d | 2012-12-28 10:50:17 +0000 | [diff] [blame] | 842 | if (anc_found == false && ftest->k >= SKF_AD_OFF) |
| 843 | return -EINVAL; |
Hagen Paul Pfeifer | 01f2f3f | 2010-06-19 17:05:36 +0000 | [diff] [blame] | 844 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 845 | } |
| 846 | |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 847 | /* Last instruction must be a RET code */ |
Hagen Paul Pfeifer | 01f2f3f | 2010-06-19 17:05:36 +0000 | [diff] [blame] | 848 | switch (filter[flen - 1].code) { |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 849 | case BPF_RET | BPF_K: |
| 850 | case BPF_RET | BPF_A: |
Eric Dumazet | 2d5311e | 2010-12-01 20:46:24 +0000 | [diff] [blame] | 851 | return check_load_and_stores(filter, flen); |
Tetsuo Handa | cba328f | 2010-11-16 15:19:51 +0000 | [diff] [blame] | 852 | } |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 853 | |
Tetsuo Handa | cba328f | 2010-11-16 15:19:51 +0000 | [diff] [blame] | 854 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 855 | } |
| 856 | |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 857 | static int bpf_prog_store_orig_filter(struct bpf_prog *fp, |
| 858 | const struct sock_fprog *fprog) |
Daniel Borkmann | a3ea269 | 2014-03-28 18:58:19 +0100 | [diff] [blame] | 859 | { |
Alexei Starovoitov | 009937e | 2014-07-30 20:34:13 -0700 | [diff] [blame] | 860 | unsigned int fsize = bpf_classic_proglen(fprog); |
Daniel Borkmann | a3ea269 | 2014-03-28 18:58:19 +0100 | [diff] [blame] | 861 | struct sock_fprog_kern *fkprog; |
| 862 | |
| 863 | fp->orig_prog = kmalloc(sizeof(*fkprog), GFP_KERNEL); |
| 864 | if (!fp->orig_prog) |
| 865 | return -ENOMEM; |
| 866 | |
| 867 | fkprog = fp->orig_prog; |
| 868 | fkprog->len = fprog->len; |
Daniel Borkmann | 658da93 | 2015-05-06 16:12:29 +0200 | [diff] [blame] | 869 | |
| 870 | fkprog->filter = kmemdup(fp->insns, fsize, |
| 871 | GFP_KERNEL | __GFP_NOWARN); |
Daniel Borkmann | a3ea269 | 2014-03-28 18:58:19 +0100 | [diff] [blame] | 872 | if (!fkprog->filter) { |
| 873 | kfree(fp->orig_prog); |
| 874 | return -ENOMEM; |
| 875 | } |
| 876 | |
| 877 | return 0; |
| 878 | } |
| 879 | |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 880 | static void bpf_release_orig_filter(struct bpf_prog *fp) |
Daniel Borkmann | a3ea269 | 2014-03-28 18:58:19 +0100 | [diff] [blame] | 881 | { |
| 882 | struct sock_fprog_kern *fprog = fp->orig_prog; |
| 883 | |
| 884 | if (fprog) { |
| 885 | kfree(fprog->filter); |
| 886 | kfree(fprog); |
| 887 | } |
| 888 | } |
| 889 | |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 890 | static void __bpf_prog_release(struct bpf_prog *prog) |
| 891 | { |
Daniel Borkmann | 24701ec | 2015-03-01 12:31:47 +0100 | [diff] [blame] | 892 | if (prog->type == BPF_PROG_TYPE_SOCKET_FILTER) { |
Alexei Starovoitov | 89aa075 | 2014-12-01 15:06:35 -0800 | [diff] [blame] | 893 | bpf_prog_put(prog); |
| 894 | } else { |
| 895 | bpf_release_orig_filter(prog); |
| 896 | bpf_prog_free(prog); |
| 897 | } |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 898 | } |
| 899 | |
Pablo Neira | 34c5bd6 | 2014-07-29 17:36:28 +0200 | [diff] [blame] | 900 | static void __sk_filter_release(struct sk_filter *fp) |
| 901 | { |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 902 | __bpf_prog_release(fp->prog); |
| 903 | kfree(fp); |
Pablo Neira | 34c5bd6 | 2014-07-29 17:36:28 +0200 | [diff] [blame] | 904 | } |
| 905 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 906 | /** |
Eric Dumazet | 46bcf14 | 2010-12-06 09:29:43 -0800 | [diff] [blame] | 907 | * sk_filter_release_rcu - Release a socket filter by rcu_head |
Pavel Emelyanov | 47e958e | 2007-10-17 21:22:42 -0700 | [diff] [blame] | 908 | * @rcu: rcu_head that contains the sk_filter to free |
| 909 | */ |
Daniel Borkmann | fbc907f | 2014-03-28 18:58:20 +0100 | [diff] [blame] | 910 | static void sk_filter_release_rcu(struct rcu_head *rcu) |
Pavel Emelyanov | 47e958e | 2007-10-17 21:22:42 -0700 | [diff] [blame] | 911 | { |
| 912 | struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu); |
| 913 | |
Pablo Neira | 34c5bd6 | 2014-07-29 17:36:28 +0200 | [diff] [blame] | 914 | __sk_filter_release(fp); |
Pavel Emelyanov | 47e958e | 2007-10-17 21:22:42 -0700 | [diff] [blame] | 915 | } |
Daniel Borkmann | fbc907f | 2014-03-28 18:58:20 +0100 | [diff] [blame] | 916 | |
| 917 | /** |
| 918 | * sk_filter_release - release a socket filter |
| 919 | * @fp: filter to remove |
| 920 | * |
| 921 | * Remove a filter from a socket and release its resources. |
| 922 | */ |
| 923 | static void sk_filter_release(struct sk_filter *fp) |
| 924 | { |
| 925 | if (atomic_dec_and_test(&fp->refcnt)) |
| 926 | call_rcu(&fp->rcu, sk_filter_release_rcu); |
| 927 | } |
| 928 | |
| 929 | void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp) |
| 930 | { |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 931 | u32 filter_size = bpf_prog_size(fp->prog->len); |
Alexei Starovoitov | 278571b | 2014-07-30 20:34:12 -0700 | [diff] [blame] | 932 | |
| 933 | atomic_sub(filter_size, &sk->sk_omem_alloc); |
Daniel Borkmann | fbc907f | 2014-03-28 18:58:20 +0100 | [diff] [blame] | 934 | sk_filter_release(fp); |
| 935 | } |
| 936 | |
Alexei Starovoitov | 278571b | 2014-07-30 20:34:12 -0700 | [diff] [blame] | 937 | /* try to charge the socket memory if there is space available |
| 938 | * return true on success |
| 939 | */ |
| 940 | bool sk_filter_charge(struct sock *sk, struct sk_filter *fp) |
Daniel Borkmann | fbc907f | 2014-03-28 18:58:20 +0100 | [diff] [blame] | 941 | { |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 942 | u32 filter_size = bpf_prog_size(fp->prog->len); |
Pavel Emelyanov | 47e958e | 2007-10-17 21:22:42 -0700 | [diff] [blame] | 943 | |
Alexei Starovoitov | 278571b | 2014-07-30 20:34:12 -0700 | [diff] [blame] | 944 | /* same check as in sock_kmalloc() */ |
| 945 | if (filter_size <= sysctl_optmem_max && |
| 946 | atomic_read(&sk->sk_omem_alloc) + filter_size < sysctl_optmem_max) { |
| 947 | atomic_inc(&fp->refcnt); |
| 948 | atomic_add(filter_size, &sk->sk_omem_alloc); |
| 949 | return true; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 950 | } |
Alexei Starovoitov | 278571b | 2014-07-30 20:34:12 -0700 | [diff] [blame] | 951 | return false; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 952 | } |
| 953 | |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 954 | static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp) |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 955 | { |
| 956 | struct sock_filter *old_prog; |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 957 | struct bpf_prog *old_fp; |
Daniel Borkmann | 3480593 | 2014-05-29 10:22:50 +0200 | [diff] [blame] | 958 | int err, new_len, old_len = fp->len; |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 959 | |
| 960 | /* We are free to overwrite insns et al right here as it |
| 961 | * won't be used at this point in time anymore internally |
| 962 | * after the migration to the internal BPF instruction |
| 963 | * representation. |
| 964 | */ |
| 965 | BUILD_BUG_ON(sizeof(struct sock_filter) != |
Alexei Starovoitov | 2695fb5 | 2014-07-24 16:38:21 -0700 | [diff] [blame] | 966 | sizeof(struct bpf_insn)); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 967 | |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 968 | /* Conversion cannot happen on overlapping memory areas, |
| 969 | * so we need to keep the user BPF around until the 2nd |
| 970 | * pass. At this time, the user BPF is stored in fp->insns. |
| 971 | */ |
| 972 | old_prog = kmemdup(fp->insns, old_len * sizeof(struct sock_filter), |
Daniel Borkmann | 658da93 | 2015-05-06 16:12:29 +0200 | [diff] [blame] | 973 | GFP_KERNEL | __GFP_NOWARN); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 974 | if (!old_prog) { |
| 975 | err = -ENOMEM; |
| 976 | goto out_err; |
| 977 | } |
| 978 | |
| 979 | /* 1st pass: calculate the new program length. */ |
Alexei Starovoitov | 8fb575c | 2014-07-30 20:34:15 -0700 | [diff] [blame] | 980 | err = bpf_convert_filter(old_prog, old_len, NULL, &new_len); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 981 | if (err) |
| 982 | goto out_err_free; |
| 983 | |
| 984 | /* Expand fp for appending the new filter representation. */ |
| 985 | old_fp = fp; |
Daniel Borkmann | 60a3b22 | 2014-09-02 22:53:44 +0200 | [diff] [blame] | 986 | fp = bpf_prog_realloc(old_fp, bpf_prog_size(new_len), 0); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 987 | if (!fp) { |
| 988 | /* The old_fp is still around in case we couldn't |
| 989 | * allocate new memory, so uncharge on that one. |
| 990 | */ |
| 991 | fp = old_fp; |
| 992 | err = -ENOMEM; |
| 993 | goto out_err_free; |
| 994 | } |
| 995 | |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 996 | fp->len = new_len; |
| 997 | |
Alexei Starovoitov | 2695fb5 | 2014-07-24 16:38:21 -0700 | [diff] [blame] | 998 | /* 2nd pass: remap sock_filter insns into bpf_insn insns. */ |
Alexei Starovoitov | 8fb575c | 2014-07-30 20:34:15 -0700 | [diff] [blame] | 999 | err = bpf_convert_filter(old_prog, old_len, fp->insnsi, &new_len); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 1000 | if (err) |
Alexei Starovoitov | 8fb575c | 2014-07-30 20:34:15 -0700 | [diff] [blame] | 1001 | /* 2nd bpf_convert_filter() can fail only if it fails |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 1002 | * to allocate memory, remapping must succeed. Note, |
| 1003 | * that at this time old_fp has already been released |
Alexei Starovoitov | 278571b | 2014-07-30 20:34:12 -0700 | [diff] [blame] | 1004 | * by krealloc(). |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 1005 | */ |
| 1006 | goto out_err_free; |
| 1007 | |
Daniel Borkmann | d1c55ab | 2016-05-13 19:08:31 +0200 | [diff] [blame] | 1008 | /* We are guaranteed to never error here with cBPF to eBPF |
| 1009 | * transitions, since there's no issue with type compatibility |
| 1010 | * checks on program arrays. |
| 1011 | */ |
| 1012 | fp = bpf_prog_select_runtime(fp, &err); |
Alexei Starovoitov | 5fe821a | 2014-05-19 14:56:14 -0700 | [diff] [blame] | 1013 | |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 1014 | kfree(old_prog); |
| 1015 | return fp; |
| 1016 | |
| 1017 | out_err_free: |
| 1018 | kfree(old_prog); |
| 1019 | out_err: |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 1020 | __bpf_prog_release(fp); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 1021 | return ERR_PTR(err); |
| 1022 | } |
| 1023 | |
Daniel Borkmann | ac67eb2 | 2015-05-06 16:12:30 +0200 | [diff] [blame] | 1024 | static struct bpf_prog *bpf_prepare_filter(struct bpf_prog *fp, |
| 1025 | bpf_aux_classic_check_t trans) |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1026 | { |
| 1027 | int err; |
| 1028 | |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 1029 | fp->bpf_func = NULL; |
Daniel Borkmann | a91263d | 2015-09-30 01:41:50 +0200 | [diff] [blame] | 1030 | fp->jited = 0; |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1031 | |
Alexei Starovoitov | 4df95ff | 2014-07-30 20:34:14 -0700 | [diff] [blame] | 1032 | err = bpf_check_classic(fp->insns, fp->len); |
Leon Yu | 418c96a | 2014-06-01 05:37:25 +0000 | [diff] [blame] | 1033 | if (err) { |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 1034 | __bpf_prog_release(fp); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 1035 | return ERR_PTR(err); |
Leon Yu | 418c96a | 2014-06-01 05:37:25 +0000 | [diff] [blame] | 1036 | } |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1037 | |
Nicolas Schichan | 4ae92bc | 2015-05-06 16:12:27 +0200 | [diff] [blame] | 1038 | /* There might be additional checks and transformations |
| 1039 | * needed on classic filters, f.e. in case of seccomp. |
| 1040 | */ |
| 1041 | if (trans) { |
| 1042 | err = trans(fp->insns, fp->len); |
| 1043 | if (err) { |
| 1044 | __bpf_prog_release(fp); |
| 1045 | return ERR_PTR(err); |
| 1046 | } |
| 1047 | } |
| 1048 | |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 1049 | /* Probe if we can JIT compile the filter and if so, do |
| 1050 | * the compilation of the filter. |
| 1051 | */ |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1052 | bpf_jit_compile(fp); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 1053 | |
| 1054 | /* JIT compiler couldn't process this filter, so do the |
| 1055 | * internal BPF translation for the optimized interpreter. |
| 1056 | */ |
Alexei Starovoitov | 5fe821a | 2014-05-19 14:56:14 -0700 | [diff] [blame] | 1057 | if (!fp->jited) |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 1058 | fp = bpf_migrate_filter(fp); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 1059 | |
| 1060 | return fp; |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1061 | } |
| 1062 | |
| 1063 | /** |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 1064 | * bpf_prog_create - create an unattached filter |
Randy Dunlap | c6c4b97 | 2012-06-08 14:01:44 +0000 | [diff] [blame] | 1065 | * @pfp: the unattached filter that is created |
Tobias Klauser | 677a9fd | 2014-06-24 15:33:21 +0200 | [diff] [blame] | 1066 | * @fprog: the filter program |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1067 | * |
Randy Dunlap | c6c4b97 | 2012-06-08 14:01:44 +0000 | [diff] [blame] | 1068 | * Create a filter independent of any socket. We first run some |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1069 | * sanity checks on it to make sure it does not explode on us later. |
| 1070 | * If an error occurs or there is insufficient memory for the filter |
| 1071 | * a negative errno code is returned. On success the return is zero. |
| 1072 | */ |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 1073 | int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog) |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1074 | { |
Alexei Starovoitov | 009937e | 2014-07-30 20:34:13 -0700 | [diff] [blame] | 1075 | unsigned int fsize = bpf_classic_proglen(fprog); |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 1076 | struct bpf_prog *fp; |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1077 | |
| 1078 | /* Make sure new filter is there and in the right amounts. */ |
Daniel Borkmann | f7bd9e3 | 2016-06-10 21:19:07 +0200 | [diff] [blame] | 1079 | if (!bpf_check_basics_ok(fprog->filter, fprog->len)) |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1080 | return -EINVAL; |
| 1081 | |
Daniel Borkmann | 60a3b22 | 2014-09-02 22:53:44 +0200 | [diff] [blame] | 1082 | fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0); |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1083 | if (!fp) |
| 1084 | return -ENOMEM; |
Daniel Borkmann | a3ea269 | 2014-03-28 18:58:19 +0100 | [diff] [blame] | 1085 | |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1086 | memcpy(fp->insns, fprog->filter, fsize); |
| 1087 | |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1088 | fp->len = fprog->len; |
Daniel Borkmann | a3ea269 | 2014-03-28 18:58:19 +0100 | [diff] [blame] | 1089 | /* Since unattached filters are not copied back to user |
| 1090 | * space through sk_get_filter(), we do not need to hold |
| 1091 | * a copy here, and can spare us the work. |
| 1092 | */ |
| 1093 | fp->orig_prog = NULL; |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1094 | |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 1095 | /* bpf_prepare_filter() already takes care of freeing |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 1096 | * memory in case something goes wrong. |
| 1097 | */ |
Nicolas Schichan | 4ae92bc | 2015-05-06 16:12:27 +0200 | [diff] [blame] | 1098 | fp = bpf_prepare_filter(fp, NULL); |
Alexei Starovoitov | bd4cf0e | 2014-03-28 18:58:25 +0100 | [diff] [blame] | 1099 | if (IS_ERR(fp)) |
| 1100 | return PTR_ERR(fp); |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1101 | |
| 1102 | *pfp = fp; |
| 1103 | return 0; |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1104 | } |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 1105 | EXPORT_SYMBOL_GPL(bpf_prog_create); |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1106 | |
Daniel Borkmann | ac67eb2 | 2015-05-06 16:12:30 +0200 | [diff] [blame] | 1107 | /** |
| 1108 | * bpf_prog_create_from_user - create an unattached filter from user buffer |
| 1109 | * @pfp: the unattached filter that is created |
| 1110 | * @fprog: the filter program |
| 1111 | * @trans: post-classic verifier transformation handler |
Daniel Borkmann | bab1899 | 2015-10-02 15:17:33 +0200 | [diff] [blame] | 1112 | * @save_orig: save classic BPF program |
Daniel Borkmann | ac67eb2 | 2015-05-06 16:12:30 +0200 | [diff] [blame] | 1113 | * |
| 1114 | * This function effectively does the same as bpf_prog_create(), only |
| 1115 | * that it builds up its insns buffer from user space provided buffer. |
| 1116 | * It also allows for passing a bpf_aux_classic_check_t handler. |
| 1117 | */ |
| 1118 | int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog, |
Daniel Borkmann | bab1899 | 2015-10-02 15:17:33 +0200 | [diff] [blame] | 1119 | bpf_aux_classic_check_t trans, bool save_orig) |
Daniel Borkmann | ac67eb2 | 2015-05-06 16:12:30 +0200 | [diff] [blame] | 1120 | { |
| 1121 | unsigned int fsize = bpf_classic_proglen(fprog); |
| 1122 | struct bpf_prog *fp; |
Daniel Borkmann | bab1899 | 2015-10-02 15:17:33 +0200 | [diff] [blame] | 1123 | int err; |
Daniel Borkmann | ac67eb2 | 2015-05-06 16:12:30 +0200 | [diff] [blame] | 1124 | |
| 1125 | /* Make sure new filter is there and in the right amounts. */ |
Daniel Borkmann | f7bd9e3 | 2016-06-10 21:19:07 +0200 | [diff] [blame] | 1126 | if (!bpf_check_basics_ok(fprog->filter, fprog->len)) |
Daniel Borkmann | ac67eb2 | 2015-05-06 16:12:30 +0200 | [diff] [blame] | 1127 | return -EINVAL; |
| 1128 | |
| 1129 | fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0); |
| 1130 | if (!fp) |
| 1131 | return -ENOMEM; |
| 1132 | |
| 1133 | if (copy_from_user(fp->insns, fprog->filter, fsize)) { |
| 1134 | __bpf_prog_free(fp); |
| 1135 | return -EFAULT; |
| 1136 | } |
| 1137 | |
| 1138 | fp->len = fprog->len; |
Daniel Borkmann | ac67eb2 | 2015-05-06 16:12:30 +0200 | [diff] [blame] | 1139 | fp->orig_prog = NULL; |
| 1140 | |
Daniel Borkmann | bab1899 | 2015-10-02 15:17:33 +0200 | [diff] [blame] | 1141 | if (save_orig) { |
| 1142 | err = bpf_prog_store_orig_filter(fp, fprog); |
| 1143 | if (err) { |
| 1144 | __bpf_prog_free(fp); |
| 1145 | return -ENOMEM; |
| 1146 | } |
| 1147 | } |
| 1148 | |
Daniel Borkmann | ac67eb2 | 2015-05-06 16:12:30 +0200 | [diff] [blame] | 1149 | /* bpf_prepare_filter() already takes care of freeing |
| 1150 | * memory in case something goes wrong. |
| 1151 | */ |
| 1152 | fp = bpf_prepare_filter(fp, trans); |
| 1153 | if (IS_ERR(fp)) |
| 1154 | return PTR_ERR(fp); |
| 1155 | |
| 1156 | *pfp = fp; |
| 1157 | return 0; |
| 1158 | } |
David S. Miller | 2ea273d | 2015-08-17 14:37:06 -0700 | [diff] [blame] | 1159 | EXPORT_SYMBOL_GPL(bpf_prog_create_from_user); |
Daniel Borkmann | ac67eb2 | 2015-05-06 16:12:30 +0200 | [diff] [blame] | 1160 | |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 1161 | void bpf_prog_destroy(struct bpf_prog *fp) |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1162 | { |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 1163 | __bpf_prog_release(fp); |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1164 | } |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 1165 | EXPORT_SYMBOL_GPL(bpf_prog_destroy); |
Jiri Pirko | 302d663 | 2012-03-31 11:01:19 +0000 | [diff] [blame] | 1166 | |
Hannes Frederic Sowa | 8ced425 | 2016-04-05 17:10:16 +0200 | [diff] [blame] | 1167 | static int __sk_attach_prog(struct bpf_prog *prog, struct sock *sk) |
Daniel Borkmann | 49b31e5 | 2015-03-02 12:25:51 +0100 | [diff] [blame] | 1168 | { |
| 1169 | struct sk_filter *fp, *old_fp; |
| 1170 | |
| 1171 | fp = kmalloc(sizeof(*fp), GFP_KERNEL); |
| 1172 | if (!fp) |
| 1173 | return -ENOMEM; |
| 1174 | |
| 1175 | fp->prog = prog; |
| 1176 | atomic_set(&fp->refcnt, 0); |
| 1177 | |
| 1178 | if (!sk_filter_charge(sk, fp)) { |
| 1179 | kfree(fp); |
| 1180 | return -ENOMEM; |
| 1181 | } |
| 1182 | |
Hannes Frederic Sowa | 8ced425 | 2016-04-05 17:10:16 +0200 | [diff] [blame] | 1183 | old_fp = rcu_dereference_protected(sk->sk_filter, |
| 1184 | lockdep_sock_is_held(sk)); |
Daniel Borkmann | 49b31e5 | 2015-03-02 12:25:51 +0100 | [diff] [blame] | 1185 | rcu_assign_pointer(sk->sk_filter, fp); |
Hannes Frederic Sowa | 8ced425 | 2016-04-05 17:10:16 +0200 | [diff] [blame] | 1186 | |
Daniel Borkmann | 49b31e5 | 2015-03-02 12:25:51 +0100 | [diff] [blame] | 1187 | if (old_fp) |
| 1188 | sk_filter_uncharge(sk, old_fp); |
| 1189 | |
| 1190 | return 0; |
| 1191 | } |
| 1192 | |
Craig Gallek | 538950a | 2016-01-04 17:41:47 -0500 | [diff] [blame] | 1193 | static int __reuseport_attach_prog(struct bpf_prog *prog, struct sock *sk) |
| 1194 | { |
| 1195 | struct bpf_prog *old_prog; |
| 1196 | int err; |
| 1197 | |
| 1198 | if (bpf_prog_size(prog->len) > sysctl_optmem_max) |
| 1199 | return -ENOMEM; |
| 1200 | |
Craig Gallek | fa46349 | 2016-02-10 11:50:39 -0500 | [diff] [blame] | 1201 | if (sk_unhashed(sk) && sk->sk_reuseport) { |
Craig Gallek | 538950a | 2016-01-04 17:41:47 -0500 | [diff] [blame] | 1202 | err = reuseport_alloc(sk); |
| 1203 | if (err) |
| 1204 | return err; |
| 1205 | } else if (!rcu_access_pointer(sk->sk_reuseport_cb)) { |
| 1206 | /* The socket wasn't bound with SO_REUSEPORT */ |
| 1207 | return -EINVAL; |
| 1208 | } |
| 1209 | |
| 1210 | old_prog = reuseport_attach_prog(sk, prog); |
| 1211 | if (old_prog) |
| 1212 | bpf_prog_destroy(old_prog); |
| 1213 | |
| 1214 | return 0; |
| 1215 | } |
| 1216 | |
| 1217 | static |
| 1218 | struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk) |
| 1219 | { |
| 1220 | unsigned int fsize = bpf_classic_proglen(fprog); |
Craig Gallek | 538950a | 2016-01-04 17:41:47 -0500 | [diff] [blame] | 1221 | struct bpf_prog *prog; |
| 1222 | int err; |
| 1223 | |
| 1224 | if (sock_flag(sk, SOCK_FILTER_LOCKED)) |
| 1225 | return ERR_PTR(-EPERM); |
| 1226 | |
| 1227 | /* Make sure new filter is there and in the right amounts. */ |
Daniel Borkmann | f7bd9e3 | 2016-06-10 21:19:07 +0200 | [diff] [blame] | 1228 | if (!bpf_check_basics_ok(fprog->filter, fprog->len)) |
Craig Gallek | 538950a | 2016-01-04 17:41:47 -0500 | [diff] [blame] | 1229 | return ERR_PTR(-EINVAL); |
| 1230 | |
Daniel Borkmann | f7bd9e3 | 2016-06-10 21:19:07 +0200 | [diff] [blame] | 1231 | prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0); |
Craig Gallek | 538950a | 2016-01-04 17:41:47 -0500 | [diff] [blame] | 1232 | if (!prog) |
| 1233 | return ERR_PTR(-ENOMEM); |
| 1234 | |
| 1235 | if (copy_from_user(prog->insns, fprog->filter, fsize)) { |
| 1236 | __bpf_prog_free(prog); |
| 1237 | return ERR_PTR(-EFAULT); |
| 1238 | } |
| 1239 | |
| 1240 | prog->len = fprog->len; |
| 1241 | |
| 1242 | err = bpf_prog_store_orig_filter(prog, fprog); |
| 1243 | if (err) { |
| 1244 | __bpf_prog_free(prog); |
| 1245 | return ERR_PTR(-ENOMEM); |
| 1246 | } |
| 1247 | |
| 1248 | /* bpf_prepare_filter() already takes care of freeing |
| 1249 | * memory in case something goes wrong. |
| 1250 | */ |
| 1251 | return bpf_prepare_filter(prog, NULL); |
| 1252 | } |
| 1253 | |
Pavel Emelyanov | 47e958e | 2007-10-17 21:22:42 -0700 | [diff] [blame] | 1254 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1255 | * sk_attach_filter - attach a socket filter |
| 1256 | * @fprog: the filter program |
| 1257 | * @sk: the socket to use |
| 1258 | * |
| 1259 | * Attach the user's filter code. We first run some sanity checks on |
| 1260 | * it to make sure it does not explode on us later. If an error |
| 1261 | * occurs or there is insufficient memory for the filter a negative |
| 1262 | * errno code is returned. On success the return is zero. |
| 1263 | */ |
Hannes Frederic Sowa | 8ced425 | 2016-04-05 17:10:16 +0200 | [diff] [blame] | 1264 | int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1265 | { |
Craig Gallek | 538950a | 2016-01-04 17:41:47 -0500 | [diff] [blame] | 1266 | struct bpf_prog *prog = __get_filter(fprog, sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1267 | int err; |
| 1268 | |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 1269 | if (IS_ERR(prog)) |
| 1270 | return PTR_ERR(prog); |
| 1271 | |
Hannes Frederic Sowa | 8ced425 | 2016-04-05 17:10:16 +0200 | [diff] [blame] | 1272 | err = __sk_attach_prog(prog, sk); |
Daniel Borkmann | 49b31e5 | 2015-03-02 12:25:51 +0100 | [diff] [blame] | 1273 | if (err < 0) { |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 1274 | __bpf_prog_release(prog); |
Daniel Borkmann | 49b31e5 | 2015-03-02 12:25:51 +0100 | [diff] [blame] | 1275 | return err; |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 1276 | } |
Daniel Borkmann | a3ea269 | 2014-03-28 18:58:19 +0100 | [diff] [blame] | 1277 | |
Pavel Emelyanov | d3904b7 | 2007-10-17 21:22:17 -0700 | [diff] [blame] | 1278 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1279 | } |
Hannes Frederic Sowa | 8ced425 | 2016-04-05 17:10:16 +0200 | [diff] [blame] | 1280 | EXPORT_SYMBOL_GPL(sk_attach_filter); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1281 | |
Craig Gallek | 538950a | 2016-01-04 17:41:47 -0500 | [diff] [blame] | 1282 | int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk) |
Alexei Starovoitov | 89aa075 | 2014-12-01 15:06:35 -0800 | [diff] [blame] | 1283 | { |
Craig Gallek | 538950a | 2016-01-04 17:41:47 -0500 | [diff] [blame] | 1284 | struct bpf_prog *prog = __get_filter(fprog, sk); |
Daniel Borkmann | 49b31e5 | 2015-03-02 12:25:51 +0100 | [diff] [blame] | 1285 | int err; |
Alexei Starovoitov | 89aa075 | 2014-12-01 15:06:35 -0800 | [diff] [blame] | 1286 | |
Alexei Starovoitov | 198bf1b | 2014-12-10 20:14:55 -0800 | [diff] [blame] | 1287 | if (IS_ERR(prog)) |
| 1288 | return PTR_ERR(prog); |
Alexei Starovoitov | 89aa075 | 2014-12-01 15:06:35 -0800 | [diff] [blame] | 1289 | |
Craig Gallek | 538950a | 2016-01-04 17:41:47 -0500 | [diff] [blame] | 1290 | err = __reuseport_attach_prog(prog, sk); |
| 1291 | if (err < 0) { |
| 1292 | __bpf_prog_release(prog); |
| 1293 | return err; |
Alexei Starovoitov | 89aa075 | 2014-12-01 15:06:35 -0800 | [diff] [blame] | 1294 | } |
| 1295 | |
Craig Gallek | 538950a | 2016-01-04 17:41:47 -0500 | [diff] [blame] | 1296 | return 0; |
| 1297 | } |
| 1298 | |
| 1299 | static struct bpf_prog *__get_bpf(u32 ufd, struct sock *sk) |
| 1300 | { |
Craig Gallek | 538950a | 2016-01-04 17:41:47 -0500 | [diff] [blame] | 1301 | if (sock_flag(sk, SOCK_FILTER_LOCKED)) |
| 1302 | return ERR_PTR(-EPERM); |
| 1303 | |
Daniel Borkmann | 113214b | 2016-06-30 17:24:44 +0200 | [diff] [blame] | 1304 | return bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER); |
Craig Gallek | 538950a | 2016-01-04 17:41:47 -0500 | [diff] [blame] | 1305 | } |
| 1306 | |
| 1307 | int sk_attach_bpf(u32 ufd, struct sock *sk) |
| 1308 | { |
| 1309 | struct bpf_prog *prog = __get_bpf(ufd, sk); |
| 1310 | int err; |
| 1311 | |
| 1312 | if (IS_ERR(prog)) |
| 1313 | return PTR_ERR(prog); |
| 1314 | |
Hannes Frederic Sowa | 8ced425 | 2016-04-05 17:10:16 +0200 | [diff] [blame] | 1315 | err = __sk_attach_prog(prog, sk); |
Daniel Borkmann | 49b31e5 | 2015-03-02 12:25:51 +0100 | [diff] [blame] | 1316 | if (err < 0) { |
Alexei Starovoitov | 89aa075 | 2014-12-01 15:06:35 -0800 | [diff] [blame] | 1317 | bpf_prog_put(prog); |
Daniel Borkmann | 49b31e5 | 2015-03-02 12:25:51 +0100 | [diff] [blame] | 1318 | return err; |
Alexei Starovoitov | 89aa075 | 2014-12-01 15:06:35 -0800 | [diff] [blame] | 1319 | } |
Alexei Starovoitov | 89aa075 | 2014-12-01 15:06:35 -0800 | [diff] [blame] | 1320 | |
Alexei Starovoitov | 89aa075 | 2014-12-01 15:06:35 -0800 | [diff] [blame] | 1321 | return 0; |
| 1322 | } |
| 1323 | |
Craig Gallek | 538950a | 2016-01-04 17:41:47 -0500 | [diff] [blame] | 1324 | int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk) |
| 1325 | { |
| 1326 | struct bpf_prog *prog = __get_bpf(ufd, sk); |
| 1327 | int err; |
| 1328 | |
| 1329 | if (IS_ERR(prog)) |
| 1330 | return PTR_ERR(prog); |
| 1331 | |
| 1332 | err = __reuseport_attach_prog(prog, sk); |
| 1333 | if (err < 0) { |
| 1334 | bpf_prog_put(prog); |
| 1335 | return err; |
| 1336 | } |
| 1337 | |
| 1338 | return 0; |
| 1339 | } |
| 1340 | |
Daniel Borkmann | 21cafc1 | 2016-02-19 23:05:24 +0100 | [diff] [blame] | 1341 | struct bpf_scratchpad { |
| 1342 | union { |
| 1343 | __be32 diff[MAX_BPF_STACK / sizeof(__be32)]; |
| 1344 | u8 buff[MAX_BPF_STACK]; |
| 1345 | }; |
| 1346 | }; |
| 1347 | |
| 1348 | static DEFINE_PER_CPU(struct bpf_scratchpad, bpf_sp); |
Alexei Starovoitov | 91bc4822 | 2015-04-01 17:12:13 -0700 | [diff] [blame] | 1349 | |
Daniel Borkmann | 5293efe | 2016-08-18 01:00:39 +0200 | [diff] [blame] | 1350 | static inline int __bpf_try_make_writable(struct sk_buff *skb, |
| 1351 | unsigned int write_len) |
| 1352 | { |
| 1353 | return skb_ensure_writable(skb, write_len); |
| 1354 | } |
| 1355 | |
Alexei Starovoitov | db58ba4 | 2016-05-05 19:49:12 -0700 | [diff] [blame] | 1356 | static inline int bpf_try_make_writable(struct sk_buff *skb, |
| 1357 | unsigned int write_len) |
| 1358 | { |
Daniel Borkmann | 5293efe | 2016-08-18 01:00:39 +0200 | [diff] [blame] | 1359 | int err = __bpf_try_make_writable(skb, write_len); |
Alexei Starovoitov | db58ba4 | 2016-05-05 19:49:12 -0700 | [diff] [blame] | 1360 | |
Daniel Borkmann | 0ed661d | 2016-08-11 21:38:37 +0200 | [diff] [blame] | 1361 | bpf_compute_data_end(skb); |
Alexei Starovoitov | db58ba4 | 2016-05-05 19:49:12 -0700 | [diff] [blame] | 1362 | return err; |
| 1363 | } |
| 1364 | |
Daniel Borkmann | 36bbef5 | 2016-09-20 00:26:13 +0200 | [diff] [blame] | 1365 | static int bpf_try_make_head_writable(struct sk_buff *skb) |
| 1366 | { |
| 1367 | return bpf_try_make_writable(skb, skb_headlen(skb)); |
| 1368 | } |
| 1369 | |
Daniel Borkmann | a2bfe6b | 2016-08-05 00:11:11 +0200 | [diff] [blame] | 1370 | static inline void bpf_push_mac_rcsum(struct sk_buff *skb) |
| 1371 | { |
| 1372 | if (skb_at_tc_ingress(skb)) |
| 1373 | skb_postpush_rcsum(skb, skb_mac_header(skb), skb->mac_len); |
| 1374 | } |
| 1375 | |
Daniel Borkmann | 8065694 | 2016-08-05 00:11:13 +0200 | [diff] [blame] | 1376 | static inline void bpf_pull_mac_rcsum(struct sk_buff *skb) |
| 1377 | { |
| 1378 | if (skb_at_tc_ingress(skb)) |
| 1379 | skb_postpull_rcsum(skb, skb_mac_header(skb), skb->mac_len); |
| 1380 | } |
| 1381 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 1382 | BPF_CALL_5(bpf_skb_store_bytes, struct sk_buff *, skb, u32, offset, |
| 1383 | const void *, from, u32, len, u64, flags) |
Alexei Starovoitov | 608cd71 | 2015-03-26 19:53:57 -0700 | [diff] [blame] | 1384 | { |
Alexei Starovoitov | 608cd71 | 2015-03-26 19:53:57 -0700 | [diff] [blame] | 1385 | void *ptr; |
| 1386 | |
Daniel Borkmann | 8afd54c | 2016-03-04 15:15:03 +0100 | [diff] [blame] | 1387 | if (unlikely(flags & ~(BPF_F_RECOMPUTE_CSUM | BPF_F_INVALIDATE_HASH))) |
Daniel Borkmann | 781c53b | 2016-01-11 01:16:38 +0100 | [diff] [blame] | 1388 | return -EINVAL; |
Daniel Borkmann | 0ed661d | 2016-08-11 21:38:37 +0200 | [diff] [blame] | 1389 | if (unlikely(offset > 0xffff)) |
Alexei Starovoitov | 608cd71 | 2015-03-26 19:53:57 -0700 | [diff] [blame] | 1390 | return -EFAULT; |
Alexei Starovoitov | db58ba4 | 2016-05-05 19:49:12 -0700 | [diff] [blame] | 1391 | if (unlikely(bpf_try_make_writable(skb, offset + len))) |
Alexei Starovoitov | 608cd71 | 2015-03-26 19:53:57 -0700 | [diff] [blame] | 1392 | return -EFAULT; |
| 1393 | |
Daniel Borkmann | 0ed661d | 2016-08-11 21:38:37 +0200 | [diff] [blame] | 1394 | ptr = skb->data + offset; |
Daniel Borkmann | 781c53b | 2016-01-11 01:16:38 +0100 | [diff] [blame] | 1395 | if (flags & BPF_F_RECOMPUTE_CSUM) |
Daniel Borkmann | 479ffcc | 2016-08-05 00:11:12 +0200 | [diff] [blame] | 1396 | __skb_postpull_rcsum(skb, ptr, len, offset); |
Alexei Starovoitov | 608cd71 | 2015-03-26 19:53:57 -0700 | [diff] [blame] | 1397 | |
| 1398 | memcpy(ptr, from, len); |
| 1399 | |
Daniel Borkmann | 781c53b | 2016-01-11 01:16:38 +0100 | [diff] [blame] | 1400 | if (flags & BPF_F_RECOMPUTE_CSUM) |
Daniel Borkmann | 479ffcc | 2016-08-05 00:11:12 +0200 | [diff] [blame] | 1401 | __skb_postpush_rcsum(skb, ptr, len, offset); |
Daniel Borkmann | 8afd54c | 2016-03-04 15:15:03 +0100 | [diff] [blame] | 1402 | if (flags & BPF_F_INVALIDATE_HASH) |
| 1403 | skb_clear_hash(skb); |
Daniel Borkmann | f8ffad69 | 2016-01-07 15:50:23 +0100 | [diff] [blame] | 1404 | |
Alexei Starovoitov | 608cd71 | 2015-03-26 19:53:57 -0700 | [diff] [blame] | 1405 | return 0; |
| 1406 | } |
| 1407 | |
Daniel Borkmann | 577c50a | 2016-03-04 15:15:04 +0100 | [diff] [blame] | 1408 | static const struct bpf_func_proto bpf_skb_store_bytes_proto = { |
Alexei Starovoitov | 608cd71 | 2015-03-26 19:53:57 -0700 | [diff] [blame] | 1409 | .func = bpf_skb_store_bytes, |
| 1410 | .gpl_only = false, |
| 1411 | .ret_type = RET_INTEGER, |
| 1412 | .arg1_type = ARG_PTR_TO_CTX, |
| 1413 | .arg2_type = ARG_ANYTHING, |
| 1414 | .arg3_type = ARG_PTR_TO_STACK, |
| 1415 | .arg4_type = ARG_CONST_STACK_SIZE, |
Alexei Starovoitov | 91bc4822 | 2015-04-01 17:12:13 -0700 | [diff] [blame] | 1416 | .arg5_type = ARG_ANYTHING, |
| 1417 | }; |
| 1418 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 1419 | BPF_CALL_4(bpf_skb_load_bytes, const struct sk_buff *, skb, u32, offset, |
| 1420 | void *, to, u32, len) |
Daniel Borkmann | 05c74e5 | 2015-12-17 23:51:53 +0100 | [diff] [blame] | 1421 | { |
Daniel Borkmann | 05c74e5 | 2015-12-17 23:51:53 +0100 | [diff] [blame] | 1422 | void *ptr; |
| 1423 | |
Daniel Borkmann | 0ed661d | 2016-08-11 21:38:37 +0200 | [diff] [blame] | 1424 | if (unlikely(offset > 0xffff)) |
Daniel Borkmann | 074f528 | 2016-04-13 00:10:52 +0200 | [diff] [blame] | 1425 | goto err_clear; |
Daniel Borkmann | 05c74e5 | 2015-12-17 23:51:53 +0100 | [diff] [blame] | 1426 | |
| 1427 | ptr = skb_header_pointer(skb, offset, len, to); |
| 1428 | if (unlikely(!ptr)) |
Daniel Borkmann | 074f528 | 2016-04-13 00:10:52 +0200 | [diff] [blame] | 1429 | goto err_clear; |
Daniel Borkmann | 05c74e5 | 2015-12-17 23:51:53 +0100 | [diff] [blame] | 1430 | if (ptr != to) |
| 1431 | memcpy(to, ptr, len); |
| 1432 | |
| 1433 | return 0; |
Daniel Borkmann | 074f528 | 2016-04-13 00:10:52 +0200 | [diff] [blame] | 1434 | err_clear: |
| 1435 | memset(to, 0, len); |
| 1436 | return -EFAULT; |
Daniel Borkmann | 05c74e5 | 2015-12-17 23:51:53 +0100 | [diff] [blame] | 1437 | } |
| 1438 | |
Daniel Borkmann | 577c50a | 2016-03-04 15:15:04 +0100 | [diff] [blame] | 1439 | static const struct bpf_func_proto bpf_skb_load_bytes_proto = { |
Daniel Borkmann | 05c74e5 | 2015-12-17 23:51:53 +0100 | [diff] [blame] | 1440 | .func = bpf_skb_load_bytes, |
| 1441 | .gpl_only = false, |
| 1442 | .ret_type = RET_INTEGER, |
| 1443 | .arg1_type = ARG_PTR_TO_CTX, |
| 1444 | .arg2_type = ARG_ANYTHING, |
Daniel Borkmann | 074f528 | 2016-04-13 00:10:52 +0200 | [diff] [blame] | 1445 | .arg3_type = ARG_PTR_TO_RAW_STACK, |
Daniel Borkmann | 05c74e5 | 2015-12-17 23:51:53 +0100 | [diff] [blame] | 1446 | .arg4_type = ARG_CONST_STACK_SIZE, |
| 1447 | }; |
| 1448 | |
Daniel Borkmann | 36bbef5 | 2016-09-20 00:26:13 +0200 | [diff] [blame] | 1449 | BPF_CALL_2(bpf_skb_pull_data, struct sk_buff *, skb, u32, len) |
| 1450 | { |
| 1451 | /* Idea is the following: should the needed direct read/write |
| 1452 | * test fail during runtime, we can pull in more data and redo |
| 1453 | * again, since implicitly, we invalidate previous checks here. |
| 1454 | * |
| 1455 | * Or, since we know how much we need to make read/writeable, |
| 1456 | * this can be done once at the program beginning for direct |
| 1457 | * access case. By this we overcome limitations of only current |
| 1458 | * headroom being accessible. |
| 1459 | */ |
| 1460 | return bpf_try_make_writable(skb, len ? : skb_headlen(skb)); |
| 1461 | } |
| 1462 | |
| 1463 | static const struct bpf_func_proto bpf_skb_pull_data_proto = { |
| 1464 | .func = bpf_skb_pull_data, |
| 1465 | .gpl_only = false, |
| 1466 | .ret_type = RET_INTEGER, |
| 1467 | .arg1_type = ARG_PTR_TO_CTX, |
| 1468 | .arg2_type = ARG_ANYTHING, |
| 1469 | }; |
| 1470 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 1471 | BPF_CALL_5(bpf_l3_csum_replace, struct sk_buff *, skb, u32, offset, |
| 1472 | u64, from, u64, to, u64, flags) |
Alexei Starovoitov | 91bc4822 | 2015-04-01 17:12:13 -0700 | [diff] [blame] | 1473 | { |
Daniel Borkmann | 0ed661d | 2016-08-11 21:38:37 +0200 | [diff] [blame] | 1474 | __sum16 *ptr; |
Alexei Starovoitov | 91bc4822 | 2015-04-01 17:12:13 -0700 | [diff] [blame] | 1475 | |
Daniel Borkmann | 781c53b | 2016-01-11 01:16:38 +0100 | [diff] [blame] | 1476 | if (unlikely(flags & ~(BPF_F_HDR_FIELD_MASK))) |
| 1477 | return -EINVAL; |
Daniel Borkmann | 0ed661d | 2016-08-11 21:38:37 +0200 | [diff] [blame] | 1478 | if (unlikely(offset > 0xffff || offset & 1)) |
Alexei Starovoitov | 91bc4822 | 2015-04-01 17:12:13 -0700 | [diff] [blame] | 1479 | return -EFAULT; |
Daniel Borkmann | 0ed661d | 2016-08-11 21:38:37 +0200 | [diff] [blame] | 1480 | if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr)))) |
Alexei Starovoitov | 91bc4822 | 2015-04-01 17:12:13 -0700 | [diff] [blame] | 1481 | return -EFAULT; |
| 1482 | |
Daniel Borkmann | 0ed661d | 2016-08-11 21:38:37 +0200 | [diff] [blame] | 1483 | ptr = (__sum16 *)(skb->data + offset); |
Daniel Borkmann | 781c53b | 2016-01-11 01:16:38 +0100 | [diff] [blame] | 1484 | switch (flags & BPF_F_HDR_FIELD_MASK) { |
Daniel Borkmann | 8050c0f | 2016-03-04 15:15:02 +0100 | [diff] [blame] | 1485 | case 0: |
| 1486 | if (unlikely(from != 0)) |
| 1487 | return -EINVAL; |
| 1488 | |
| 1489 | csum_replace_by_diff(ptr, to); |
| 1490 | break; |
Alexei Starovoitov | 91bc4822 | 2015-04-01 17:12:13 -0700 | [diff] [blame] | 1491 | case 2: |
| 1492 | csum_replace2(ptr, from, to); |
| 1493 | break; |
| 1494 | case 4: |
| 1495 | csum_replace4(ptr, from, to); |
| 1496 | break; |
| 1497 | default: |
| 1498 | return -EINVAL; |
| 1499 | } |
| 1500 | |
Alexei Starovoitov | 91bc4822 | 2015-04-01 17:12:13 -0700 | [diff] [blame] | 1501 | return 0; |
| 1502 | } |
| 1503 | |
Daniel Borkmann | 577c50a | 2016-03-04 15:15:04 +0100 | [diff] [blame] | 1504 | static const struct bpf_func_proto bpf_l3_csum_replace_proto = { |
Alexei Starovoitov | 91bc4822 | 2015-04-01 17:12:13 -0700 | [diff] [blame] | 1505 | .func = bpf_l3_csum_replace, |
| 1506 | .gpl_only = false, |
| 1507 | .ret_type = RET_INTEGER, |
| 1508 | .arg1_type = ARG_PTR_TO_CTX, |
| 1509 | .arg2_type = ARG_ANYTHING, |
| 1510 | .arg3_type = ARG_ANYTHING, |
| 1511 | .arg4_type = ARG_ANYTHING, |
| 1512 | .arg5_type = ARG_ANYTHING, |
| 1513 | }; |
| 1514 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 1515 | BPF_CALL_5(bpf_l4_csum_replace, struct sk_buff *, skb, u32, offset, |
| 1516 | u64, from, u64, to, u64, flags) |
Alexei Starovoitov | 91bc4822 | 2015-04-01 17:12:13 -0700 | [diff] [blame] | 1517 | { |
Daniel Borkmann | 781c53b | 2016-01-11 01:16:38 +0100 | [diff] [blame] | 1518 | bool is_pseudo = flags & BPF_F_PSEUDO_HDR; |
Daniel Borkmann | 2f72959 | 2016-02-19 23:05:26 +0100 | [diff] [blame] | 1519 | bool is_mmzero = flags & BPF_F_MARK_MANGLED_0; |
Daniel Borkmann | 0ed661d | 2016-08-11 21:38:37 +0200 | [diff] [blame] | 1520 | __sum16 *ptr; |
Alexei Starovoitov | 91bc4822 | 2015-04-01 17:12:13 -0700 | [diff] [blame] | 1521 | |
Daniel Borkmann | 2f72959 | 2016-02-19 23:05:26 +0100 | [diff] [blame] | 1522 | if (unlikely(flags & ~(BPF_F_MARK_MANGLED_0 | BPF_F_PSEUDO_HDR | |
| 1523 | BPF_F_HDR_FIELD_MASK))) |
Daniel Borkmann | 781c53b | 2016-01-11 01:16:38 +0100 | [diff] [blame] | 1524 | return -EINVAL; |
Daniel Borkmann | 0ed661d | 2016-08-11 21:38:37 +0200 | [diff] [blame] | 1525 | if (unlikely(offset > 0xffff || offset & 1)) |
Alexei Starovoitov | 91bc4822 | 2015-04-01 17:12:13 -0700 | [diff] [blame] | 1526 | return -EFAULT; |
Daniel Borkmann | 0ed661d | 2016-08-11 21:38:37 +0200 | [diff] [blame] | 1527 | if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr)))) |
Alexei Starovoitov | 91bc4822 | 2015-04-01 17:12:13 -0700 | [diff] [blame] | 1528 | return -EFAULT; |
| 1529 | |
Daniel Borkmann | 0ed661d | 2016-08-11 21:38:37 +0200 | [diff] [blame] | 1530 | ptr = (__sum16 *)(skb->data + offset); |
Daniel Borkmann | 2f72959 | 2016-02-19 23:05:26 +0100 | [diff] [blame] | 1531 | if (is_mmzero && !*ptr) |
| 1532 | return 0; |
Alexei Starovoitov | 91bc4822 | 2015-04-01 17:12:13 -0700 | [diff] [blame] | 1533 | |
Daniel Borkmann | 781c53b | 2016-01-11 01:16:38 +0100 | [diff] [blame] | 1534 | switch (flags & BPF_F_HDR_FIELD_MASK) { |
Daniel Borkmann | 7d67234 | 2016-02-19 23:05:23 +0100 | [diff] [blame] | 1535 | case 0: |
| 1536 | if (unlikely(from != 0)) |
| 1537 | return -EINVAL; |
| 1538 | |
| 1539 | inet_proto_csum_replace_by_diff(ptr, skb, to, is_pseudo); |
| 1540 | break; |
Alexei Starovoitov | 91bc4822 | 2015-04-01 17:12:13 -0700 | [diff] [blame] | 1541 | case 2: |
| 1542 | inet_proto_csum_replace2(ptr, skb, from, to, is_pseudo); |
| 1543 | break; |
| 1544 | case 4: |
| 1545 | inet_proto_csum_replace4(ptr, skb, from, to, is_pseudo); |
| 1546 | break; |
| 1547 | default: |
| 1548 | return -EINVAL; |
| 1549 | } |
| 1550 | |
Daniel Borkmann | 2f72959 | 2016-02-19 23:05:26 +0100 | [diff] [blame] | 1551 | if (is_mmzero && !*ptr) |
| 1552 | *ptr = CSUM_MANGLED_0; |
Alexei Starovoitov | 91bc4822 | 2015-04-01 17:12:13 -0700 | [diff] [blame] | 1553 | return 0; |
| 1554 | } |
| 1555 | |
Daniel Borkmann | 577c50a | 2016-03-04 15:15:04 +0100 | [diff] [blame] | 1556 | static const struct bpf_func_proto bpf_l4_csum_replace_proto = { |
Alexei Starovoitov | 91bc4822 | 2015-04-01 17:12:13 -0700 | [diff] [blame] | 1557 | .func = bpf_l4_csum_replace, |
| 1558 | .gpl_only = false, |
| 1559 | .ret_type = RET_INTEGER, |
| 1560 | .arg1_type = ARG_PTR_TO_CTX, |
| 1561 | .arg2_type = ARG_ANYTHING, |
| 1562 | .arg3_type = ARG_ANYTHING, |
| 1563 | .arg4_type = ARG_ANYTHING, |
| 1564 | .arg5_type = ARG_ANYTHING, |
Alexei Starovoitov | 608cd71 | 2015-03-26 19:53:57 -0700 | [diff] [blame] | 1565 | }; |
| 1566 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 1567 | BPF_CALL_5(bpf_csum_diff, __be32 *, from, u32, from_size, |
| 1568 | __be32 *, to, u32, to_size, __wsum, seed) |
Daniel Borkmann | 7d67234 | 2016-02-19 23:05:23 +0100 | [diff] [blame] | 1569 | { |
Daniel Borkmann | 21cafc1 | 2016-02-19 23:05:24 +0100 | [diff] [blame] | 1570 | struct bpf_scratchpad *sp = this_cpu_ptr(&bpf_sp); |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 1571 | u32 diff_size = from_size + to_size; |
Daniel Borkmann | 7d67234 | 2016-02-19 23:05:23 +0100 | [diff] [blame] | 1572 | int i, j = 0; |
| 1573 | |
| 1574 | /* This is quite flexible, some examples: |
| 1575 | * |
| 1576 | * from_size == 0, to_size > 0, seed := csum --> pushing data |
| 1577 | * from_size > 0, to_size == 0, seed := csum --> pulling data |
| 1578 | * from_size > 0, to_size > 0, seed := 0 --> diffing data |
| 1579 | * |
| 1580 | * Even for diffing, from_size and to_size don't need to be equal. |
| 1581 | */ |
| 1582 | if (unlikely(((from_size | to_size) & (sizeof(__be32) - 1)) || |
| 1583 | diff_size > sizeof(sp->diff))) |
| 1584 | return -EINVAL; |
| 1585 | |
| 1586 | for (i = 0; i < from_size / sizeof(__be32); i++, j++) |
| 1587 | sp->diff[j] = ~from[i]; |
| 1588 | for (i = 0; i < to_size / sizeof(__be32); i++, j++) |
| 1589 | sp->diff[j] = to[i]; |
| 1590 | |
| 1591 | return csum_partial(sp->diff, diff_size, seed); |
| 1592 | } |
| 1593 | |
Daniel Borkmann | 577c50a | 2016-03-04 15:15:04 +0100 | [diff] [blame] | 1594 | static const struct bpf_func_proto bpf_csum_diff_proto = { |
Daniel Borkmann | 7d67234 | 2016-02-19 23:05:23 +0100 | [diff] [blame] | 1595 | .func = bpf_csum_diff, |
| 1596 | .gpl_only = false, |
Daniel Borkmann | 36bbef5 | 2016-09-20 00:26:13 +0200 | [diff] [blame] | 1597 | .pkt_access = true, |
Daniel Borkmann | 7d67234 | 2016-02-19 23:05:23 +0100 | [diff] [blame] | 1598 | .ret_type = RET_INTEGER, |
| 1599 | .arg1_type = ARG_PTR_TO_STACK, |
| 1600 | .arg2_type = ARG_CONST_STACK_SIZE_OR_ZERO, |
| 1601 | .arg3_type = ARG_PTR_TO_STACK, |
| 1602 | .arg4_type = ARG_CONST_STACK_SIZE_OR_ZERO, |
| 1603 | .arg5_type = ARG_ANYTHING, |
| 1604 | }; |
| 1605 | |
Daniel Borkmann | 36bbef5 | 2016-09-20 00:26:13 +0200 | [diff] [blame] | 1606 | BPF_CALL_2(bpf_csum_update, struct sk_buff *, skb, __wsum, csum) |
| 1607 | { |
| 1608 | /* The interface is to be used in combination with bpf_csum_diff() |
| 1609 | * for direct packet writes. csum rotation for alignment as well |
| 1610 | * as emulating csum_sub() can be done from the eBPF program. |
| 1611 | */ |
| 1612 | if (skb->ip_summed == CHECKSUM_COMPLETE) |
| 1613 | return (skb->csum = csum_add(skb->csum, csum)); |
| 1614 | |
| 1615 | return -ENOTSUPP; |
| 1616 | } |
| 1617 | |
| 1618 | static const struct bpf_func_proto bpf_csum_update_proto = { |
| 1619 | .func = bpf_csum_update, |
| 1620 | .gpl_only = false, |
| 1621 | .ret_type = RET_INTEGER, |
| 1622 | .arg1_type = ARG_PTR_TO_CTX, |
| 1623 | .arg2_type = ARG_ANYTHING, |
| 1624 | }; |
| 1625 | |
Daniel Borkmann | a70b506 | 2016-06-10 21:19:06 +0200 | [diff] [blame] | 1626 | static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb) |
| 1627 | { |
Daniel Borkmann | a70b506 | 2016-06-10 21:19:06 +0200 | [diff] [blame] | 1628 | return dev_forward_skb(dev, skb); |
| 1629 | } |
| 1630 | |
| 1631 | static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb) |
| 1632 | { |
| 1633 | int ret; |
| 1634 | |
| 1635 | if (unlikely(__this_cpu_read(xmit_recursion) > XMIT_RECURSION_LIMIT)) { |
| 1636 | net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n"); |
| 1637 | kfree_skb(skb); |
| 1638 | return -ENETDOWN; |
| 1639 | } |
| 1640 | |
| 1641 | skb->dev = dev; |
| 1642 | |
| 1643 | __this_cpu_inc(xmit_recursion); |
| 1644 | ret = dev_queue_xmit(skb); |
| 1645 | __this_cpu_dec(xmit_recursion); |
| 1646 | |
| 1647 | return ret; |
| 1648 | } |
| 1649 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 1650 | BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags) |
Alexei Starovoitov | 3896d65 | 2015-06-02 16:03:14 -0700 | [diff] [blame] | 1651 | { |
Alexei Starovoitov | 3896d65 | 2015-06-02 16:03:14 -0700 | [diff] [blame] | 1652 | struct net_device *dev; |
Daniel Borkmann | 36bbef5 | 2016-09-20 00:26:13 +0200 | [diff] [blame] | 1653 | struct sk_buff *clone; |
| 1654 | int ret; |
Alexei Starovoitov | 3896d65 | 2015-06-02 16:03:14 -0700 | [diff] [blame] | 1655 | |
Daniel Borkmann | 781c53b | 2016-01-11 01:16:38 +0100 | [diff] [blame] | 1656 | if (unlikely(flags & ~(BPF_F_INGRESS))) |
| 1657 | return -EINVAL; |
| 1658 | |
Alexei Starovoitov | 3896d65 | 2015-06-02 16:03:14 -0700 | [diff] [blame] | 1659 | dev = dev_get_by_index_rcu(dev_net(skb->dev), ifindex); |
| 1660 | if (unlikely(!dev)) |
| 1661 | return -EINVAL; |
| 1662 | |
Daniel Borkmann | 36bbef5 | 2016-09-20 00:26:13 +0200 | [diff] [blame] | 1663 | clone = skb_clone(skb, GFP_ATOMIC); |
| 1664 | if (unlikely(!clone)) |
Alexei Starovoitov | 3896d65 | 2015-06-02 16:03:14 -0700 | [diff] [blame] | 1665 | return -ENOMEM; |
| 1666 | |
Daniel Borkmann | 36bbef5 | 2016-09-20 00:26:13 +0200 | [diff] [blame] | 1667 | /* For direct write, we need to keep the invariant that the skbs |
| 1668 | * we're dealing with need to be uncloned. Should uncloning fail |
| 1669 | * here, we need to free the just generated clone to unclone once |
| 1670 | * again. |
| 1671 | */ |
| 1672 | ret = bpf_try_make_head_writable(skb); |
| 1673 | if (unlikely(ret)) { |
| 1674 | kfree_skb(clone); |
| 1675 | return -ENOMEM; |
| 1676 | } |
| 1677 | |
| 1678 | bpf_push_mac_rcsum(clone); |
Daniel Borkmann | a2bfe6b | 2016-08-05 00:11:11 +0200 | [diff] [blame] | 1679 | |
Daniel Borkmann | a70b506 | 2016-06-10 21:19:06 +0200 | [diff] [blame] | 1680 | return flags & BPF_F_INGRESS ? |
Daniel Borkmann | 36bbef5 | 2016-09-20 00:26:13 +0200 | [diff] [blame] | 1681 | __bpf_rx_skb(dev, clone) : __bpf_tx_skb(dev, clone); |
Alexei Starovoitov | 3896d65 | 2015-06-02 16:03:14 -0700 | [diff] [blame] | 1682 | } |
| 1683 | |
Daniel Borkmann | 577c50a | 2016-03-04 15:15:04 +0100 | [diff] [blame] | 1684 | static const struct bpf_func_proto bpf_clone_redirect_proto = { |
Alexei Starovoitov | 3896d65 | 2015-06-02 16:03:14 -0700 | [diff] [blame] | 1685 | .func = bpf_clone_redirect, |
| 1686 | .gpl_only = false, |
| 1687 | .ret_type = RET_INTEGER, |
| 1688 | .arg1_type = ARG_PTR_TO_CTX, |
| 1689 | .arg2_type = ARG_ANYTHING, |
| 1690 | .arg3_type = ARG_ANYTHING, |
| 1691 | }; |
| 1692 | |
Alexei Starovoitov | 27b29f6 | 2015-09-15 23:05:43 -0700 | [diff] [blame] | 1693 | struct redirect_info { |
| 1694 | u32 ifindex; |
| 1695 | u32 flags; |
| 1696 | }; |
| 1697 | |
| 1698 | static DEFINE_PER_CPU(struct redirect_info, redirect_info); |
Daniel Borkmann | 781c53b | 2016-01-11 01:16:38 +0100 | [diff] [blame] | 1699 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 1700 | BPF_CALL_2(bpf_redirect, u32, ifindex, u64, flags) |
Alexei Starovoitov | 27b29f6 | 2015-09-15 23:05:43 -0700 | [diff] [blame] | 1701 | { |
| 1702 | struct redirect_info *ri = this_cpu_ptr(&redirect_info); |
| 1703 | |
Daniel Borkmann | 781c53b | 2016-01-11 01:16:38 +0100 | [diff] [blame] | 1704 | if (unlikely(flags & ~(BPF_F_INGRESS))) |
| 1705 | return TC_ACT_SHOT; |
| 1706 | |
Alexei Starovoitov | 27b29f6 | 2015-09-15 23:05:43 -0700 | [diff] [blame] | 1707 | ri->ifindex = ifindex; |
| 1708 | ri->flags = flags; |
Daniel Borkmann | 781c53b | 2016-01-11 01:16:38 +0100 | [diff] [blame] | 1709 | |
Alexei Starovoitov | 27b29f6 | 2015-09-15 23:05:43 -0700 | [diff] [blame] | 1710 | return TC_ACT_REDIRECT; |
| 1711 | } |
| 1712 | |
| 1713 | int skb_do_redirect(struct sk_buff *skb) |
| 1714 | { |
| 1715 | struct redirect_info *ri = this_cpu_ptr(&redirect_info); |
| 1716 | struct net_device *dev; |
| 1717 | |
| 1718 | dev = dev_get_by_index_rcu(dev_net(skb->dev), ri->ifindex); |
| 1719 | ri->ifindex = 0; |
| 1720 | if (unlikely(!dev)) { |
| 1721 | kfree_skb(skb); |
| 1722 | return -EINVAL; |
| 1723 | } |
| 1724 | |
Daniel Borkmann | a2bfe6b | 2016-08-05 00:11:11 +0200 | [diff] [blame] | 1725 | bpf_push_mac_rcsum(skb); |
| 1726 | |
Daniel Borkmann | a70b506 | 2016-06-10 21:19:06 +0200 | [diff] [blame] | 1727 | return ri->flags & BPF_F_INGRESS ? |
| 1728 | __bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb); |
Alexei Starovoitov | 27b29f6 | 2015-09-15 23:05:43 -0700 | [diff] [blame] | 1729 | } |
| 1730 | |
Daniel Borkmann | 577c50a | 2016-03-04 15:15:04 +0100 | [diff] [blame] | 1731 | static const struct bpf_func_proto bpf_redirect_proto = { |
Alexei Starovoitov | 27b29f6 | 2015-09-15 23:05:43 -0700 | [diff] [blame] | 1732 | .func = bpf_redirect, |
| 1733 | .gpl_only = false, |
| 1734 | .ret_type = RET_INTEGER, |
| 1735 | .arg1_type = ARG_ANYTHING, |
| 1736 | .arg2_type = ARG_ANYTHING, |
| 1737 | }; |
| 1738 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 1739 | BPF_CALL_1(bpf_get_cgroup_classid, const struct sk_buff *, skb) |
Daniel Borkmann | 8d20aab | 2015-07-15 14:21:42 +0200 | [diff] [blame] | 1740 | { |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 1741 | return task_get_classid(skb); |
Daniel Borkmann | 8d20aab | 2015-07-15 14:21:42 +0200 | [diff] [blame] | 1742 | } |
| 1743 | |
| 1744 | static const struct bpf_func_proto bpf_get_cgroup_classid_proto = { |
| 1745 | .func = bpf_get_cgroup_classid, |
| 1746 | .gpl_only = false, |
| 1747 | .ret_type = RET_INTEGER, |
| 1748 | .arg1_type = ARG_PTR_TO_CTX, |
| 1749 | }; |
| 1750 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 1751 | BPF_CALL_1(bpf_get_route_realm, const struct sk_buff *, skb) |
Daniel Borkmann | c46646d | 2015-09-30 01:41:51 +0200 | [diff] [blame] | 1752 | { |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 1753 | return dst_tclassid(skb); |
Daniel Borkmann | c46646d | 2015-09-30 01:41:51 +0200 | [diff] [blame] | 1754 | } |
| 1755 | |
| 1756 | static const struct bpf_func_proto bpf_get_route_realm_proto = { |
| 1757 | .func = bpf_get_route_realm, |
| 1758 | .gpl_only = false, |
| 1759 | .ret_type = RET_INTEGER, |
| 1760 | .arg1_type = ARG_PTR_TO_CTX, |
| 1761 | }; |
| 1762 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 1763 | BPF_CALL_1(bpf_get_hash_recalc, struct sk_buff *, skb) |
Daniel Borkmann | 13c5c24 | 2016-07-03 01:28:47 +0200 | [diff] [blame] | 1764 | { |
| 1765 | /* If skb_clear_hash() was called due to mangling, we can |
| 1766 | * trigger SW recalculation here. Later access to hash |
| 1767 | * can then use the inline skb->hash via context directly |
| 1768 | * instead of calling this helper again. |
| 1769 | */ |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 1770 | return skb_get_hash(skb); |
Daniel Borkmann | 13c5c24 | 2016-07-03 01:28:47 +0200 | [diff] [blame] | 1771 | } |
| 1772 | |
| 1773 | static const struct bpf_func_proto bpf_get_hash_recalc_proto = { |
| 1774 | .func = bpf_get_hash_recalc, |
| 1775 | .gpl_only = false, |
| 1776 | .ret_type = RET_INTEGER, |
| 1777 | .arg1_type = ARG_PTR_TO_CTX, |
| 1778 | }; |
| 1779 | |
Daniel Borkmann | 7a4b28c | 2016-09-23 01:28:37 +0200 | [diff] [blame] | 1780 | BPF_CALL_1(bpf_set_hash_invalid, struct sk_buff *, skb) |
| 1781 | { |
| 1782 | /* After all direct packet write, this can be used once for |
| 1783 | * triggering a lazy recalc on next skb_get_hash() invocation. |
| 1784 | */ |
| 1785 | skb_clear_hash(skb); |
| 1786 | return 0; |
| 1787 | } |
| 1788 | |
| 1789 | static const struct bpf_func_proto bpf_set_hash_invalid_proto = { |
| 1790 | .func = bpf_set_hash_invalid, |
| 1791 | .gpl_only = false, |
| 1792 | .ret_type = RET_INTEGER, |
| 1793 | .arg1_type = ARG_PTR_TO_CTX, |
| 1794 | }; |
| 1795 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 1796 | BPF_CALL_3(bpf_skb_vlan_push, struct sk_buff *, skb, __be16, vlan_proto, |
| 1797 | u16, vlan_tci) |
Alexei Starovoitov | 4e10df9 | 2015-07-20 20:34:18 -0700 | [diff] [blame] | 1798 | { |
Alexei Starovoitov | db58ba4 | 2016-05-05 19:49:12 -0700 | [diff] [blame] | 1799 | int ret; |
Alexei Starovoitov | 4e10df9 | 2015-07-20 20:34:18 -0700 | [diff] [blame] | 1800 | |
| 1801 | if (unlikely(vlan_proto != htons(ETH_P_8021Q) && |
| 1802 | vlan_proto != htons(ETH_P_8021AD))) |
| 1803 | vlan_proto = htons(ETH_P_8021Q); |
| 1804 | |
Daniel Borkmann | 8065694 | 2016-08-05 00:11:13 +0200 | [diff] [blame] | 1805 | bpf_push_mac_rcsum(skb); |
Alexei Starovoitov | db58ba4 | 2016-05-05 19:49:12 -0700 | [diff] [blame] | 1806 | ret = skb_vlan_push(skb, vlan_proto, vlan_tci); |
Daniel Borkmann | 8065694 | 2016-08-05 00:11:13 +0200 | [diff] [blame] | 1807 | bpf_pull_mac_rcsum(skb); |
| 1808 | |
Alexei Starovoitov | db58ba4 | 2016-05-05 19:49:12 -0700 | [diff] [blame] | 1809 | bpf_compute_data_end(skb); |
| 1810 | return ret; |
Alexei Starovoitov | 4e10df9 | 2015-07-20 20:34:18 -0700 | [diff] [blame] | 1811 | } |
| 1812 | |
| 1813 | const struct bpf_func_proto bpf_skb_vlan_push_proto = { |
| 1814 | .func = bpf_skb_vlan_push, |
| 1815 | .gpl_only = false, |
| 1816 | .ret_type = RET_INTEGER, |
| 1817 | .arg1_type = ARG_PTR_TO_CTX, |
| 1818 | .arg2_type = ARG_ANYTHING, |
| 1819 | .arg3_type = ARG_ANYTHING, |
| 1820 | }; |
Alexei Starovoitov | 4d9c5c5 | 2015-07-20 20:34:19 -0700 | [diff] [blame] | 1821 | EXPORT_SYMBOL_GPL(bpf_skb_vlan_push_proto); |
Alexei Starovoitov | 4e10df9 | 2015-07-20 20:34:18 -0700 | [diff] [blame] | 1822 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 1823 | BPF_CALL_1(bpf_skb_vlan_pop, struct sk_buff *, skb) |
Alexei Starovoitov | 4e10df9 | 2015-07-20 20:34:18 -0700 | [diff] [blame] | 1824 | { |
Alexei Starovoitov | db58ba4 | 2016-05-05 19:49:12 -0700 | [diff] [blame] | 1825 | int ret; |
Alexei Starovoitov | 4e10df9 | 2015-07-20 20:34:18 -0700 | [diff] [blame] | 1826 | |
Daniel Borkmann | 8065694 | 2016-08-05 00:11:13 +0200 | [diff] [blame] | 1827 | bpf_push_mac_rcsum(skb); |
Alexei Starovoitov | db58ba4 | 2016-05-05 19:49:12 -0700 | [diff] [blame] | 1828 | ret = skb_vlan_pop(skb); |
Daniel Borkmann | 8065694 | 2016-08-05 00:11:13 +0200 | [diff] [blame] | 1829 | bpf_pull_mac_rcsum(skb); |
| 1830 | |
Alexei Starovoitov | db58ba4 | 2016-05-05 19:49:12 -0700 | [diff] [blame] | 1831 | bpf_compute_data_end(skb); |
| 1832 | return ret; |
Alexei Starovoitov | 4e10df9 | 2015-07-20 20:34:18 -0700 | [diff] [blame] | 1833 | } |
| 1834 | |
| 1835 | const struct bpf_func_proto bpf_skb_vlan_pop_proto = { |
| 1836 | .func = bpf_skb_vlan_pop, |
| 1837 | .gpl_only = false, |
| 1838 | .ret_type = RET_INTEGER, |
| 1839 | .arg1_type = ARG_PTR_TO_CTX, |
| 1840 | }; |
Alexei Starovoitov | 4d9c5c5 | 2015-07-20 20:34:19 -0700 | [diff] [blame] | 1841 | EXPORT_SYMBOL_GPL(bpf_skb_vlan_pop_proto); |
Alexei Starovoitov | 4e10df9 | 2015-07-20 20:34:18 -0700 | [diff] [blame] | 1842 | |
Daniel Borkmann | 6578171 | 2016-06-28 12:18:27 +0200 | [diff] [blame] | 1843 | static int bpf_skb_generic_push(struct sk_buff *skb, u32 off, u32 len) |
| 1844 | { |
| 1845 | /* Caller already did skb_cow() with len as headroom, |
| 1846 | * so no need to do it here. |
| 1847 | */ |
| 1848 | skb_push(skb, len); |
| 1849 | memmove(skb->data, skb->data + len, off); |
| 1850 | memset(skb->data + off, 0, len); |
| 1851 | |
| 1852 | /* No skb_postpush_rcsum(skb, skb->data + off, len) |
| 1853 | * needed here as it does not change the skb->csum |
| 1854 | * result for checksum complete when summing over |
| 1855 | * zeroed blocks. |
| 1856 | */ |
| 1857 | return 0; |
| 1858 | } |
| 1859 | |
| 1860 | static int bpf_skb_generic_pop(struct sk_buff *skb, u32 off, u32 len) |
| 1861 | { |
| 1862 | /* skb_ensure_writable() is not needed here, as we're |
| 1863 | * already working on an uncloned skb. |
| 1864 | */ |
| 1865 | if (unlikely(!pskb_may_pull(skb, off + len))) |
| 1866 | return -ENOMEM; |
| 1867 | |
| 1868 | skb_postpull_rcsum(skb, skb->data + off, len); |
| 1869 | memmove(skb->data + len, skb->data, off); |
| 1870 | __skb_pull(skb, len); |
| 1871 | |
| 1872 | return 0; |
| 1873 | } |
| 1874 | |
| 1875 | static int bpf_skb_net_hdr_push(struct sk_buff *skb, u32 off, u32 len) |
| 1876 | { |
| 1877 | bool trans_same = skb->transport_header == skb->network_header; |
| 1878 | int ret; |
| 1879 | |
| 1880 | /* There's no need for __skb_push()/__skb_pull() pair to |
| 1881 | * get to the start of the mac header as we're guaranteed |
| 1882 | * to always start from here under eBPF. |
| 1883 | */ |
| 1884 | ret = bpf_skb_generic_push(skb, off, len); |
| 1885 | if (likely(!ret)) { |
| 1886 | skb->mac_header -= len; |
| 1887 | skb->network_header -= len; |
| 1888 | if (trans_same) |
| 1889 | skb->transport_header = skb->network_header; |
| 1890 | } |
| 1891 | |
| 1892 | return ret; |
| 1893 | } |
| 1894 | |
| 1895 | static int bpf_skb_net_hdr_pop(struct sk_buff *skb, u32 off, u32 len) |
| 1896 | { |
| 1897 | bool trans_same = skb->transport_header == skb->network_header; |
| 1898 | int ret; |
| 1899 | |
| 1900 | /* Same here, __skb_push()/__skb_pull() pair not needed. */ |
| 1901 | ret = bpf_skb_generic_pop(skb, off, len); |
| 1902 | if (likely(!ret)) { |
| 1903 | skb->mac_header += len; |
| 1904 | skb->network_header += len; |
| 1905 | if (trans_same) |
| 1906 | skb->transport_header = skb->network_header; |
| 1907 | } |
| 1908 | |
| 1909 | return ret; |
| 1910 | } |
| 1911 | |
| 1912 | static int bpf_skb_proto_4_to_6(struct sk_buff *skb) |
| 1913 | { |
| 1914 | const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr); |
| 1915 | u32 off = skb->network_header - skb->mac_header; |
| 1916 | int ret; |
| 1917 | |
| 1918 | ret = skb_cow(skb, len_diff); |
| 1919 | if (unlikely(ret < 0)) |
| 1920 | return ret; |
| 1921 | |
| 1922 | ret = bpf_skb_net_hdr_push(skb, off, len_diff); |
| 1923 | if (unlikely(ret < 0)) |
| 1924 | return ret; |
| 1925 | |
| 1926 | if (skb_is_gso(skb)) { |
| 1927 | /* SKB_GSO_UDP stays as is. SKB_GSO_TCPV4 needs to |
| 1928 | * be changed into SKB_GSO_TCPV6. |
| 1929 | */ |
| 1930 | if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) { |
| 1931 | skb_shinfo(skb)->gso_type &= ~SKB_GSO_TCPV4; |
| 1932 | skb_shinfo(skb)->gso_type |= SKB_GSO_TCPV6; |
| 1933 | } |
| 1934 | |
| 1935 | /* Due to IPv6 header, MSS needs to be downgraded. */ |
| 1936 | skb_shinfo(skb)->gso_size -= len_diff; |
| 1937 | /* Header must be checked, and gso_segs recomputed. */ |
| 1938 | skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; |
| 1939 | skb_shinfo(skb)->gso_segs = 0; |
| 1940 | } |
| 1941 | |
| 1942 | skb->protocol = htons(ETH_P_IPV6); |
| 1943 | skb_clear_hash(skb); |
| 1944 | |
| 1945 | return 0; |
| 1946 | } |
| 1947 | |
| 1948 | static int bpf_skb_proto_6_to_4(struct sk_buff *skb) |
| 1949 | { |
| 1950 | const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr); |
| 1951 | u32 off = skb->network_header - skb->mac_header; |
| 1952 | int ret; |
| 1953 | |
| 1954 | ret = skb_unclone(skb, GFP_ATOMIC); |
| 1955 | if (unlikely(ret < 0)) |
| 1956 | return ret; |
| 1957 | |
| 1958 | ret = bpf_skb_net_hdr_pop(skb, off, len_diff); |
| 1959 | if (unlikely(ret < 0)) |
| 1960 | return ret; |
| 1961 | |
| 1962 | if (skb_is_gso(skb)) { |
| 1963 | /* SKB_GSO_UDP stays as is. SKB_GSO_TCPV6 needs to |
| 1964 | * be changed into SKB_GSO_TCPV4. |
| 1965 | */ |
| 1966 | if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6) { |
| 1967 | skb_shinfo(skb)->gso_type &= ~SKB_GSO_TCPV6; |
| 1968 | skb_shinfo(skb)->gso_type |= SKB_GSO_TCPV4; |
| 1969 | } |
| 1970 | |
| 1971 | /* Due to IPv4 header, MSS can be upgraded. */ |
| 1972 | skb_shinfo(skb)->gso_size += len_diff; |
| 1973 | /* Header must be checked, and gso_segs recomputed. */ |
| 1974 | skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; |
| 1975 | skb_shinfo(skb)->gso_segs = 0; |
| 1976 | } |
| 1977 | |
| 1978 | skb->protocol = htons(ETH_P_IP); |
| 1979 | skb_clear_hash(skb); |
| 1980 | |
| 1981 | return 0; |
| 1982 | } |
| 1983 | |
| 1984 | static int bpf_skb_proto_xlat(struct sk_buff *skb, __be16 to_proto) |
| 1985 | { |
| 1986 | __be16 from_proto = skb->protocol; |
| 1987 | |
| 1988 | if (from_proto == htons(ETH_P_IP) && |
| 1989 | to_proto == htons(ETH_P_IPV6)) |
| 1990 | return bpf_skb_proto_4_to_6(skb); |
| 1991 | |
| 1992 | if (from_proto == htons(ETH_P_IPV6) && |
| 1993 | to_proto == htons(ETH_P_IP)) |
| 1994 | return bpf_skb_proto_6_to_4(skb); |
| 1995 | |
| 1996 | return -ENOTSUPP; |
| 1997 | } |
| 1998 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 1999 | BPF_CALL_3(bpf_skb_change_proto, struct sk_buff *, skb, __be16, proto, |
| 2000 | u64, flags) |
Daniel Borkmann | 6578171 | 2016-06-28 12:18:27 +0200 | [diff] [blame] | 2001 | { |
Daniel Borkmann | 6578171 | 2016-06-28 12:18:27 +0200 | [diff] [blame] | 2002 | int ret; |
| 2003 | |
| 2004 | if (unlikely(flags)) |
| 2005 | return -EINVAL; |
| 2006 | |
| 2007 | /* General idea is that this helper does the basic groundwork |
| 2008 | * needed for changing the protocol, and eBPF program fills the |
| 2009 | * rest through bpf_skb_store_bytes(), bpf_lX_csum_replace() |
| 2010 | * and other helpers, rather than passing a raw buffer here. |
| 2011 | * |
| 2012 | * The rationale is to keep this minimal and without a need to |
| 2013 | * deal with raw packet data. F.e. even if we would pass buffers |
| 2014 | * here, the program still needs to call the bpf_lX_csum_replace() |
| 2015 | * helpers anyway. Plus, this way we keep also separation of |
| 2016 | * concerns, since f.e. bpf_skb_store_bytes() should only take |
| 2017 | * care of stores. |
| 2018 | * |
| 2019 | * Currently, additional options and extension header space are |
| 2020 | * not supported, but flags register is reserved so we can adapt |
| 2021 | * that. For offloads, we mark packet as dodgy, so that headers |
| 2022 | * need to be verified first. |
| 2023 | */ |
| 2024 | ret = bpf_skb_proto_xlat(skb, proto); |
| 2025 | bpf_compute_data_end(skb); |
| 2026 | return ret; |
| 2027 | } |
| 2028 | |
| 2029 | static const struct bpf_func_proto bpf_skb_change_proto_proto = { |
| 2030 | .func = bpf_skb_change_proto, |
| 2031 | .gpl_only = false, |
| 2032 | .ret_type = RET_INTEGER, |
| 2033 | .arg1_type = ARG_PTR_TO_CTX, |
| 2034 | .arg2_type = ARG_ANYTHING, |
| 2035 | .arg3_type = ARG_ANYTHING, |
| 2036 | }; |
| 2037 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 2038 | BPF_CALL_2(bpf_skb_change_type, struct sk_buff *, skb, u32, pkt_type) |
Daniel Borkmann | d2485c4 | 2016-06-28 12:18:28 +0200 | [diff] [blame] | 2039 | { |
Daniel Borkmann | d2485c4 | 2016-06-28 12:18:28 +0200 | [diff] [blame] | 2040 | /* We only allow a restricted subset to be changed for now. */ |
Daniel Borkmann | 45c7fff | 2016-08-18 01:00:38 +0200 | [diff] [blame] | 2041 | if (unlikely(!skb_pkt_type_ok(skb->pkt_type) || |
| 2042 | !skb_pkt_type_ok(pkt_type))) |
Daniel Borkmann | d2485c4 | 2016-06-28 12:18:28 +0200 | [diff] [blame] | 2043 | return -EINVAL; |
| 2044 | |
| 2045 | skb->pkt_type = pkt_type; |
| 2046 | return 0; |
| 2047 | } |
| 2048 | |
| 2049 | static const struct bpf_func_proto bpf_skb_change_type_proto = { |
| 2050 | .func = bpf_skb_change_type, |
| 2051 | .gpl_only = false, |
| 2052 | .ret_type = RET_INTEGER, |
| 2053 | .arg1_type = ARG_PTR_TO_CTX, |
| 2054 | .arg2_type = ARG_ANYTHING, |
| 2055 | }; |
| 2056 | |
Daniel Borkmann | 5293efe | 2016-08-18 01:00:39 +0200 | [diff] [blame] | 2057 | static u32 __bpf_skb_min_len(const struct sk_buff *skb) |
| 2058 | { |
| 2059 | u32 min_len = skb_network_offset(skb); |
| 2060 | |
| 2061 | if (skb_transport_header_was_set(skb)) |
| 2062 | min_len = skb_transport_offset(skb); |
| 2063 | if (skb->ip_summed == CHECKSUM_PARTIAL) |
| 2064 | min_len = skb_checksum_start_offset(skb) + |
| 2065 | skb->csum_offset + sizeof(__sum16); |
| 2066 | return min_len; |
| 2067 | } |
| 2068 | |
| 2069 | static u32 __bpf_skb_max_len(const struct sk_buff *skb) |
| 2070 | { |
Daniel Borkmann | 6088b58 | 2016-09-09 02:45:28 +0200 | [diff] [blame] | 2071 | return skb->dev->mtu + skb->dev->hard_header_len; |
Daniel Borkmann | 5293efe | 2016-08-18 01:00:39 +0200 | [diff] [blame] | 2072 | } |
| 2073 | |
| 2074 | static int bpf_skb_grow_rcsum(struct sk_buff *skb, unsigned int new_len) |
| 2075 | { |
| 2076 | unsigned int old_len = skb->len; |
| 2077 | int ret; |
| 2078 | |
| 2079 | ret = __skb_grow_rcsum(skb, new_len); |
| 2080 | if (!ret) |
| 2081 | memset(skb->data + old_len, 0, new_len - old_len); |
| 2082 | return ret; |
| 2083 | } |
| 2084 | |
| 2085 | static int bpf_skb_trim_rcsum(struct sk_buff *skb, unsigned int new_len) |
| 2086 | { |
| 2087 | return __skb_trim_rcsum(skb, new_len); |
| 2088 | } |
| 2089 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 2090 | BPF_CALL_3(bpf_skb_change_tail, struct sk_buff *, skb, u32, new_len, |
| 2091 | u64, flags) |
Daniel Borkmann | 5293efe | 2016-08-18 01:00:39 +0200 | [diff] [blame] | 2092 | { |
Daniel Borkmann | 5293efe | 2016-08-18 01:00:39 +0200 | [diff] [blame] | 2093 | u32 max_len = __bpf_skb_max_len(skb); |
| 2094 | u32 min_len = __bpf_skb_min_len(skb); |
Daniel Borkmann | 5293efe | 2016-08-18 01:00:39 +0200 | [diff] [blame] | 2095 | int ret; |
| 2096 | |
| 2097 | if (unlikely(flags || new_len > max_len || new_len < min_len)) |
| 2098 | return -EINVAL; |
| 2099 | if (skb->encapsulation) |
| 2100 | return -ENOTSUPP; |
| 2101 | |
| 2102 | /* The basic idea of this helper is that it's performing the |
| 2103 | * needed work to either grow or trim an skb, and eBPF program |
| 2104 | * rewrites the rest via helpers like bpf_skb_store_bytes(), |
| 2105 | * bpf_lX_csum_replace() and others rather than passing a raw |
| 2106 | * buffer here. This one is a slow path helper and intended |
| 2107 | * for replies with control messages. |
| 2108 | * |
| 2109 | * Like in bpf_skb_change_proto(), we want to keep this rather |
| 2110 | * minimal and without protocol specifics so that we are able |
| 2111 | * to separate concerns as in bpf_skb_store_bytes() should only |
| 2112 | * be the one responsible for writing buffers. |
| 2113 | * |
| 2114 | * It's really expected to be a slow path operation here for |
| 2115 | * control message replies, so we're implicitly linearizing, |
| 2116 | * uncloning and drop offloads from the skb by this. |
| 2117 | */ |
| 2118 | ret = __bpf_try_make_writable(skb, skb->len); |
| 2119 | if (!ret) { |
| 2120 | if (new_len > skb->len) |
| 2121 | ret = bpf_skb_grow_rcsum(skb, new_len); |
| 2122 | else if (new_len < skb->len) |
| 2123 | ret = bpf_skb_trim_rcsum(skb, new_len); |
| 2124 | if (!ret && skb_is_gso(skb)) |
| 2125 | skb_gso_reset(skb); |
| 2126 | } |
| 2127 | |
| 2128 | bpf_compute_data_end(skb); |
| 2129 | return ret; |
| 2130 | } |
| 2131 | |
| 2132 | static const struct bpf_func_proto bpf_skb_change_tail_proto = { |
| 2133 | .func = bpf_skb_change_tail, |
| 2134 | .gpl_only = false, |
| 2135 | .ret_type = RET_INTEGER, |
| 2136 | .arg1_type = ARG_PTR_TO_CTX, |
| 2137 | .arg2_type = ARG_ANYTHING, |
| 2138 | .arg3_type = ARG_ANYTHING, |
| 2139 | }; |
| 2140 | |
Alexei Starovoitov | 4e10df9 | 2015-07-20 20:34:18 -0700 | [diff] [blame] | 2141 | bool bpf_helper_changes_skb_data(void *func) |
| 2142 | { |
Daniel Borkmann | 36bbef5 | 2016-09-20 00:26:13 +0200 | [diff] [blame] | 2143 | if (func == bpf_skb_vlan_push || |
| 2144 | func == bpf_skb_vlan_pop || |
| 2145 | func == bpf_skb_store_bytes || |
| 2146 | func == bpf_skb_change_proto || |
| 2147 | func == bpf_skb_change_tail || |
| 2148 | func == bpf_skb_pull_data || |
| 2149 | func == bpf_l3_csum_replace || |
| 2150 | func == bpf_l4_csum_replace) |
Daniel Borkmann | 3697649 | 2016-02-19 23:05:25 +0100 | [diff] [blame] | 2151 | return true; |
| 2152 | |
Alexei Starovoitov | 4e10df9 | 2015-07-20 20:34:18 -0700 | [diff] [blame] | 2153 | return false; |
| 2154 | } |
| 2155 | |
Daniel Borkmann | 555c8a8 | 2016-07-14 18:08:05 +0200 | [diff] [blame] | 2156 | static unsigned long bpf_skb_copy(void *dst_buff, const void *skb, |
Daniel Borkmann | aa7145c | 2016-07-22 01:19:42 +0200 | [diff] [blame] | 2157 | unsigned long off, unsigned long len) |
Daniel Borkmann | 555c8a8 | 2016-07-14 18:08:05 +0200 | [diff] [blame] | 2158 | { |
Daniel Borkmann | aa7145c | 2016-07-22 01:19:42 +0200 | [diff] [blame] | 2159 | void *ptr = skb_header_pointer(skb, off, len, dst_buff); |
Daniel Borkmann | 555c8a8 | 2016-07-14 18:08:05 +0200 | [diff] [blame] | 2160 | |
| 2161 | if (unlikely(!ptr)) |
| 2162 | return len; |
| 2163 | if (ptr != dst_buff) |
| 2164 | memcpy(dst_buff, ptr, len); |
| 2165 | |
| 2166 | return 0; |
| 2167 | } |
| 2168 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 2169 | BPF_CALL_5(bpf_skb_event_output, struct sk_buff *, skb, struct bpf_map *, map, |
| 2170 | u64, flags, void *, meta, u64, meta_size) |
Daniel Borkmann | 555c8a8 | 2016-07-14 18:08:05 +0200 | [diff] [blame] | 2171 | { |
Daniel Borkmann | 555c8a8 | 2016-07-14 18:08:05 +0200 | [diff] [blame] | 2172 | u64 skb_size = (flags & BPF_F_CTXLEN_MASK) >> 32; |
Daniel Borkmann | 555c8a8 | 2016-07-14 18:08:05 +0200 | [diff] [blame] | 2173 | |
| 2174 | if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK))) |
| 2175 | return -EINVAL; |
| 2176 | if (unlikely(skb_size > skb->len)) |
| 2177 | return -EFAULT; |
| 2178 | |
| 2179 | return bpf_event_output(map, flags, meta, meta_size, skb, skb_size, |
| 2180 | bpf_skb_copy); |
| 2181 | } |
| 2182 | |
| 2183 | static const struct bpf_func_proto bpf_skb_event_output_proto = { |
| 2184 | .func = bpf_skb_event_output, |
| 2185 | .gpl_only = true, |
| 2186 | .ret_type = RET_INTEGER, |
| 2187 | .arg1_type = ARG_PTR_TO_CTX, |
| 2188 | .arg2_type = ARG_CONST_MAP_PTR, |
| 2189 | .arg3_type = ARG_ANYTHING, |
| 2190 | .arg4_type = ARG_PTR_TO_STACK, |
| 2191 | .arg5_type = ARG_CONST_STACK_SIZE, |
| 2192 | }; |
| 2193 | |
Daniel Borkmann | c6c3345 | 2016-01-11 01:16:39 +0100 | [diff] [blame] | 2194 | static unsigned short bpf_tunnel_key_af(u64 flags) |
| 2195 | { |
| 2196 | return flags & BPF_F_TUNINFO_IPV6 ? AF_INET6 : AF_INET; |
| 2197 | } |
| 2198 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 2199 | BPF_CALL_4(bpf_skb_get_tunnel_key, struct sk_buff *, skb, struct bpf_tunnel_key *, to, |
| 2200 | u32, size, u64, flags) |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2201 | { |
Daniel Borkmann | c6c3345 | 2016-01-11 01:16:39 +0100 | [diff] [blame] | 2202 | const struct ip_tunnel_info *info = skb_tunnel_info(skb); |
| 2203 | u8 compat[sizeof(struct bpf_tunnel_key)]; |
Daniel Borkmann | 074f528 | 2016-04-13 00:10:52 +0200 | [diff] [blame] | 2204 | void *to_orig = to; |
| 2205 | int err; |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2206 | |
Daniel Borkmann | 074f528 | 2016-04-13 00:10:52 +0200 | [diff] [blame] | 2207 | if (unlikely(!info || (flags & ~(BPF_F_TUNINFO_IPV6)))) { |
| 2208 | err = -EINVAL; |
| 2209 | goto err_clear; |
| 2210 | } |
| 2211 | if (ip_tunnel_info_af(info) != bpf_tunnel_key_af(flags)) { |
| 2212 | err = -EPROTO; |
| 2213 | goto err_clear; |
| 2214 | } |
Daniel Borkmann | c6c3345 | 2016-01-11 01:16:39 +0100 | [diff] [blame] | 2215 | if (unlikely(size != sizeof(struct bpf_tunnel_key))) { |
Daniel Borkmann | 074f528 | 2016-04-13 00:10:52 +0200 | [diff] [blame] | 2216 | err = -EINVAL; |
Daniel Borkmann | c6c3345 | 2016-01-11 01:16:39 +0100 | [diff] [blame] | 2217 | switch (size) { |
Daniel Borkmann | 4018ab1 | 2016-03-09 03:00:05 +0100 | [diff] [blame] | 2218 | case offsetof(struct bpf_tunnel_key, tunnel_label): |
Daniel Borkmann | c0e760c | 2016-03-30 00:02:00 +0200 | [diff] [blame] | 2219 | case offsetof(struct bpf_tunnel_key, tunnel_ext): |
Daniel Borkmann | 4018ab1 | 2016-03-09 03:00:05 +0100 | [diff] [blame] | 2220 | goto set_compat; |
Daniel Borkmann | c6c3345 | 2016-01-11 01:16:39 +0100 | [diff] [blame] | 2221 | case offsetof(struct bpf_tunnel_key, remote_ipv6[1]): |
| 2222 | /* Fixup deprecated structure layouts here, so we have |
| 2223 | * a common path later on. |
| 2224 | */ |
| 2225 | if (ip_tunnel_info_af(info) != AF_INET) |
Daniel Borkmann | 074f528 | 2016-04-13 00:10:52 +0200 | [diff] [blame] | 2226 | goto err_clear; |
Daniel Borkmann | 4018ab1 | 2016-03-09 03:00:05 +0100 | [diff] [blame] | 2227 | set_compat: |
Daniel Borkmann | c6c3345 | 2016-01-11 01:16:39 +0100 | [diff] [blame] | 2228 | to = (struct bpf_tunnel_key *)compat; |
| 2229 | break; |
| 2230 | default: |
Daniel Borkmann | 074f528 | 2016-04-13 00:10:52 +0200 | [diff] [blame] | 2231 | goto err_clear; |
Daniel Borkmann | c6c3345 | 2016-01-11 01:16:39 +0100 | [diff] [blame] | 2232 | } |
| 2233 | } |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2234 | |
| 2235 | to->tunnel_id = be64_to_cpu(info->key.tun_id); |
Daniel Borkmann | c6c3345 | 2016-01-11 01:16:39 +0100 | [diff] [blame] | 2236 | to->tunnel_tos = info->key.tos; |
| 2237 | to->tunnel_ttl = info->key.ttl; |
| 2238 | |
Daniel Borkmann | 4018ab1 | 2016-03-09 03:00:05 +0100 | [diff] [blame] | 2239 | if (flags & BPF_F_TUNINFO_IPV6) { |
Daniel Borkmann | c6c3345 | 2016-01-11 01:16:39 +0100 | [diff] [blame] | 2240 | memcpy(to->remote_ipv6, &info->key.u.ipv6.src, |
| 2241 | sizeof(to->remote_ipv6)); |
Daniel Borkmann | 4018ab1 | 2016-03-09 03:00:05 +0100 | [diff] [blame] | 2242 | to->tunnel_label = be32_to_cpu(info->key.label); |
| 2243 | } else { |
Daniel Borkmann | c6c3345 | 2016-01-11 01:16:39 +0100 | [diff] [blame] | 2244 | to->remote_ipv4 = be32_to_cpu(info->key.u.ipv4.src); |
Daniel Borkmann | 4018ab1 | 2016-03-09 03:00:05 +0100 | [diff] [blame] | 2245 | } |
Daniel Borkmann | c6c3345 | 2016-01-11 01:16:39 +0100 | [diff] [blame] | 2246 | |
| 2247 | if (unlikely(size != sizeof(struct bpf_tunnel_key))) |
Daniel Borkmann | 074f528 | 2016-04-13 00:10:52 +0200 | [diff] [blame] | 2248 | memcpy(to_orig, to, size); |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2249 | |
| 2250 | return 0; |
Daniel Borkmann | 074f528 | 2016-04-13 00:10:52 +0200 | [diff] [blame] | 2251 | err_clear: |
| 2252 | memset(to_orig, 0, size); |
| 2253 | return err; |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2254 | } |
| 2255 | |
Daniel Borkmann | 577c50a | 2016-03-04 15:15:04 +0100 | [diff] [blame] | 2256 | static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto = { |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2257 | .func = bpf_skb_get_tunnel_key, |
| 2258 | .gpl_only = false, |
| 2259 | .ret_type = RET_INTEGER, |
| 2260 | .arg1_type = ARG_PTR_TO_CTX, |
Daniel Borkmann | 074f528 | 2016-04-13 00:10:52 +0200 | [diff] [blame] | 2261 | .arg2_type = ARG_PTR_TO_RAW_STACK, |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2262 | .arg3_type = ARG_CONST_STACK_SIZE, |
| 2263 | .arg4_type = ARG_ANYTHING, |
| 2264 | }; |
| 2265 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 2266 | BPF_CALL_3(bpf_skb_get_tunnel_opt, struct sk_buff *, skb, u8 *, to, u32, size) |
Daniel Borkmann | 14ca075 | 2016-03-04 15:15:06 +0100 | [diff] [blame] | 2267 | { |
Daniel Borkmann | 14ca075 | 2016-03-04 15:15:06 +0100 | [diff] [blame] | 2268 | const struct ip_tunnel_info *info = skb_tunnel_info(skb); |
Daniel Borkmann | 074f528 | 2016-04-13 00:10:52 +0200 | [diff] [blame] | 2269 | int err; |
Daniel Borkmann | 14ca075 | 2016-03-04 15:15:06 +0100 | [diff] [blame] | 2270 | |
| 2271 | if (unlikely(!info || |
Daniel Borkmann | 074f528 | 2016-04-13 00:10:52 +0200 | [diff] [blame] | 2272 | !(info->key.tun_flags & TUNNEL_OPTIONS_PRESENT))) { |
| 2273 | err = -ENOENT; |
| 2274 | goto err_clear; |
| 2275 | } |
| 2276 | if (unlikely(size < info->options_len)) { |
| 2277 | err = -ENOMEM; |
| 2278 | goto err_clear; |
| 2279 | } |
Daniel Borkmann | 14ca075 | 2016-03-04 15:15:06 +0100 | [diff] [blame] | 2280 | |
| 2281 | ip_tunnel_info_opts_get(to, info); |
Daniel Borkmann | 074f528 | 2016-04-13 00:10:52 +0200 | [diff] [blame] | 2282 | if (size > info->options_len) |
| 2283 | memset(to + info->options_len, 0, size - info->options_len); |
Daniel Borkmann | 14ca075 | 2016-03-04 15:15:06 +0100 | [diff] [blame] | 2284 | |
| 2285 | return info->options_len; |
Daniel Borkmann | 074f528 | 2016-04-13 00:10:52 +0200 | [diff] [blame] | 2286 | err_clear: |
| 2287 | memset(to, 0, size); |
| 2288 | return err; |
Daniel Borkmann | 14ca075 | 2016-03-04 15:15:06 +0100 | [diff] [blame] | 2289 | } |
| 2290 | |
| 2291 | static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto = { |
| 2292 | .func = bpf_skb_get_tunnel_opt, |
| 2293 | .gpl_only = false, |
| 2294 | .ret_type = RET_INTEGER, |
| 2295 | .arg1_type = ARG_PTR_TO_CTX, |
Daniel Borkmann | 074f528 | 2016-04-13 00:10:52 +0200 | [diff] [blame] | 2296 | .arg2_type = ARG_PTR_TO_RAW_STACK, |
Daniel Borkmann | 14ca075 | 2016-03-04 15:15:06 +0100 | [diff] [blame] | 2297 | .arg3_type = ARG_CONST_STACK_SIZE, |
| 2298 | }; |
| 2299 | |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2300 | static struct metadata_dst __percpu *md_dst; |
| 2301 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 2302 | BPF_CALL_4(bpf_skb_set_tunnel_key, struct sk_buff *, skb, |
| 2303 | const struct bpf_tunnel_key *, from, u32, size, u64, flags) |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2304 | { |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2305 | struct metadata_dst *md = this_cpu_ptr(md_dst); |
Daniel Borkmann | c6c3345 | 2016-01-11 01:16:39 +0100 | [diff] [blame] | 2306 | u8 compat[sizeof(struct bpf_tunnel_key)]; |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2307 | struct ip_tunnel_info *info; |
| 2308 | |
Daniel Borkmann | 2208087 | 2016-03-04 15:15:05 +0100 | [diff] [blame] | 2309 | if (unlikely(flags & ~(BPF_F_TUNINFO_IPV6 | BPF_F_ZERO_CSUM_TX | |
| 2310 | BPF_F_DONT_FRAGMENT))) |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2311 | return -EINVAL; |
Daniel Borkmann | c6c3345 | 2016-01-11 01:16:39 +0100 | [diff] [blame] | 2312 | if (unlikely(size != sizeof(struct bpf_tunnel_key))) { |
| 2313 | switch (size) { |
Daniel Borkmann | 4018ab1 | 2016-03-09 03:00:05 +0100 | [diff] [blame] | 2314 | case offsetof(struct bpf_tunnel_key, tunnel_label): |
Daniel Borkmann | c0e760c | 2016-03-30 00:02:00 +0200 | [diff] [blame] | 2315 | case offsetof(struct bpf_tunnel_key, tunnel_ext): |
Daniel Borkmann | c6c3345 | 2016-01-11 01:16:39 +0100 | [diff] [blame] | 2316 | case offsetof(struct bpf_tunnel_key, remote_ipv6[1]): |
| 2317 | /* Fixup deprecated structure layouts here, so we have |
| 2318 | * a common path later on. |
| 2319 | */ |
| 2320 | memcpy(compat, from, size); |
| 2321 | memset(compat + size, 0, sizeof(compat) - size); |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 2322 | from = (const struct bpf_tunnel_key *) compat; |
Daniel Borkmann | c6c3345 | 2016-01-11 01:16:39 +0100 | [diff] [blame] | 2323 | break; |
| 2324 | default: |
| 2325 | return -EINVAL; |
| 2326 | } |
| 2327 | } |
Daniel Borkmann | c0e760c | 2016-03-30 00:02:00 +0200 | [diff] [blame] | 2328 | if (unlikely((!(flags & BPF_F_TUNINFO_IPV6) && from->tunnel_label) || |
| 2329 | from->tunnel_ext)) |
Daniel Borkmann | 4018ab1 | 2016-03-09 03:00:05 +0100 | [diff] [blame] | 2330 | return -EINVAL; |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2331 | |
| 2332 | skb_dst_drop(skb); |
| 2333 | dst_hold((struct dst_entry *) md); |
| 2334 | skb_dst_set(skb, (struct dst_entry *) md); |
| 2335 | |
| 2336 | info = &md->u.tun_info; |
| 2337 | info->mode = IP_TUNNEL_INFO_TX; |
Daniel Borkmann | c6c3345 | 2016-01-11 01:16:39 +0100 | [diff] [blame] | 2338 | |
Daniel Borkmann | db3c613 | 2016-03-04 15:15:07 +0100 | [diff] [blame] | 2339 | info->key.tun_flags = TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_NOCACHE; |
Daniel Borkmann | 2208087 | 2016-03-04 15:15:05 +0100 | [diff] [blame] | 2340 | if (flags & BPF_F_DONT_FRAGMENT) |
| 2341 | info->key.tun_flags |= TUNNEL_DONT_FRAGMENT; |
| 2342 | |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2343 | info->key.tun_id = cpu_to_be64(from->tunnel_id); |
Daniel Borkmann | c6c3345 | 2016-01-11 01:16:39 +0100 | [diff] [blame] | 2344 | info->key.tos = from->tunnel_tos; |
| 2345 | info->key.ttl = from->tunnel_ttl; |
| 2346 | |
| 2347 | if (flags & BPF_F_TUNINFO_IPV6) { |
| 2348 | info->mode |= IP_TUNNEL_INFO_IPV6; |
| 2349 | memcpy(&info->key.u.ipv6.dst, from->remote_ipv6, |
| 2350 | sizeof(from->remote_ipv6)); |
Daniel Borkmann | 4018ab1 | 2016-03-09 03:00:05 +0100 | [diff] [blame] | 2351 | info->key.label = cpu_to_be32(from->tunnel_label) & |
| 2352 | IPV6_FLOWLABEL_MASK; |
Daniel Borkmann | c6c3345 | 2016-01-11 01:16:39 +0100 | [diff] [blame] | 2353 | } else { |
| 2354 | info->key.u.ipv4.dst = cpu_to_be32(from->remote_ipv4); |
Daniel Borkmann | 2da897e | 2016-02-23 02:05:26 +0100 | [diff] [blame] | 2355 | if (flags & BPF_F_ZERO_CSUM_TX) |
| 2356 | info->key.tun_flags &= ~TUNNEL_CSUM; |
Daniel Borkmann | c6c3345 | 2016-01-11 01:16:39 +0100 | [diff] [blame] | 2357 | } |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2358 | |
| 2359 | return 0; |
| 2360 | } |
| 2361 | |
Daniel Borkmann | 577c50a | 2016-03-04 15:15:04 +0100 | [diff] [blame] | 2362 | static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto = { |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2363 | .func = bpf_skb_set_tunnel_key, |
| 2364 | .gpl_only = false, |
| 2365 | .ret_type = RET_INTEGER, |
| 2366 | .arg1_type = ARG_PTR_TO_CTX, |
| 2367 | .arg2_type = ARG_PTR_TO_STACK, |
| 2368 | .arg3_type = ARG_CONST_STACK_SIZE, |
| 2369 | .arg4_type = ARG_ANYTHING, |
| 2370 | }; |
| 2371 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 2372 | BPF_CALL_3(bpf_skb_set_tunnel_opt, struct sk_buff *, skb, |
| 2373 | const u8 *, from, u32, size) |
Daniel Borkmann | 14ca075 | 2016-03-04 15:15:06 +0100 | [diff] [blame] | 2374 | { |
Daniel Borkmann | 14ca075 | 2016-03-04 15:15:06 +0100 | [diff] [blame] | 2375 | struct ip_tunnel_info *info = skb_tunnel_info(skb); |
| 2376 | const struct metadata_dst *md = this_cpu_ptr(md_dst); |
| 2377 | |
| 2378 | if (unlikely(info != &md->u.tun_info || (size & (sizeof(u32) - 1)))) |
| 2379 | return -EINVAL; |
Daniel Borkmann | fca5fdf | 2016-03-16 01:42:51 +0100 | [diff] [blame] | 2380 | if (unlikely(size > IP_TUNNEL_OPTS_MAX)) |
Daniel Borkmann | 14ca075 | 2016-03-04 15:15:06 +0100 | [diff] [blame] | 2381 | return -ENOMEM; |
| 2382 | |
| 2383 | ip_tunnel_info_opts_set(info, from, size); |
| 2384 | |
| 2385 | return 0; |
| 2386 | } |
| 2387 | |
| 2388 | static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto = { |
| 2389 | .func = bpf_skb_set_tunnel_opt, |
| 2390 | .gpl_only = false, |
| 2391 | .ret_type = RET_INTEGER, |
| 2392 | .arg1_type = ARG_PTR_TO_CTX, |
| 2393 | .arg2_type = ARG_PTR_TO_STACK, |
| 2394 | .arg3_type = ARG_CONST_STACK_SIZE, |
| 2395 | }; |
| 2396 | |
| 2397 | static const struct bpf_func_proto * |
| 2398 | bpf_get_skb_set_tunnel_proto(enum bpf_func_id which) |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2399 | { |
| 2400 | if (!md_dst) { |
Daniel Borkmann | 14ca075 | 2016-03-04 15:15:06 +0100 | [diff] [blame] | 2401 | /* Race is not possible, since it's called from verifier |
| 2402 | * that is holding verifier mutex. |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2403 | */ |
Daniel Borkmann | fca5fdf | 2016-03-16 01:42:51 +0100 | [diff] [blame] | 2404 | md_dst = metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX, |
Daniel Borkmann | 14ca075 | 2016-03-04 15:15:06 +0100 | [diff] [blame] | 2405 | GFP_KERNEL); |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2406 | if (!md_dst) |
| 2407 | return NULL; |
| 2408 | } |
Daniel Borkmann | 14ca075 | 2016-03-04 15:15:06 +0100 | [diff] [blame] | 2409 | |
| 2410 | switch (which) { |
| 2411 | case BPF_FUNC_skb_set_tunnel_key: |
| 2412 | return &bpf_skb_set_tunnel_key_proto; |
| 2413 | case BPF_FUNC_skb_set_tunnel_opt: |
| 2414 | return &bpf_skb_set_tunnel_opt_proto; |
| 2415 | default: |
| 2416 | return NULL; |
| 2417 | } |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2418 | } |
| 2419 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 2420 | BPF_CALL_3(bpf_skb_under_cgroup, struct sk_buff *, skb, struct bpf_map *, map, |
| 2421 | u32, idx) |
Martin KaFai Lau | 4a482f3 | 2016-06-30 10:28:44 -0700 | [diff] [blame] | 2422 | { |
Martin KaFai Lau | 4a482f3 | 2016-06-30 10:28:44 -0700 | [diff] [blame] | 2423 | struct bpf_array *array = container_of(map, struct bpf_array, map); |
| 2424 | struct cgroup *cgrp; |
| 2425 | struct sock *sk; |
Martin KaFai Lau | 4a482f3 | 2016-06-30 10:28:44 -0700 | [diff] [blame] | 2426 | |
Daniel Borkmann | 2d48c5f | 2016-09-23 01:28:35 +0200 | [diff] [blame] | 2427 | sk = skb_to_full_sk(skb); |
Martin KaFai Lau | 4a482f3 | 2016-06-30 10:28:44 -0700 | [diff] [blame] | 2428 | if (!sk || !sk_fullsock(sk)) |
| 2429 | return -ENOENT; |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 2430 | if (unlikely(idx >= array->map.max_entries)) |
Martin KaFai Lau | 4a482f3 | 2016-06-30 10:28:44 -0700 | [diff] [blame] | 2431 | return -E2BIG; |
| 2432 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 2433 | cgrp = READ_ONCE(array->ptrs[idx]); |
Martin KaFai Lau | 4a482f3 | 2016-06-30 10:28:44 -0700 | [diff] [blame] | 2434 | if (unlikely(!cgrp)) |
| 2435 | return -EAGAIN; |
| 2436 | |
Daniel Borkmann | 54fd9c2 | 2016-08-18 01:00:41 +0200 | [diff] [blame] | 2437 | return sk_under_cgroup_hierarchy(sk, cgrp); |
Martin KaFai Lau | 4a482f3 | 2016-06-30 10:28:44 -0700 | [diff] [blame] | 2438 | } |
| 2439 | |
Daniel Borkmann | 747ea55 | 2016-08-12 22:17:17 +0200 | [diff] [blame] | 2440 | static const struct bpf_func_proto bpf_skb_under_cgroup_proto = { |
| 2441 | .func = bpf_skb_under_cgroup, |
Martin KaFai Lau | 4a482f3 | 2016-06-30 10:28:44 -0700 | [diff] [blame] | 2442 | .gpl_only = false, |
| 2443 | .ret_type = RET_INTEGER, |
| 2444 | .arg1_type = ARG_PTR_TO_CTX, |
| 2445 | .arg2_type = ARG_CONST_MAP_PTR, |
| 2446 | .arg3_type = ARG_ANYTHING, |
| 2447 | }; |
Martin KaFai Lau | 4a482f3 | 2016-06-30 10:28:44 -0700 | [diff] [blame] | 2448 | |
Daniel Borkmann | 4de1696 | 2016-08-18 01:00:40 +0200 | [diff] [blame] | 2449 | static unsigned long bpf_xdp_copy(void *dst_buff, const void *src_buff, |
| 2450 | unsigned long off, unsigned long len) |
| 2451 | { |
| 2452 | memcpy(dst_buff, src_buff + off, len); |
| 2453 | return 0; |
| 2454 | } |
| 2455 | |
Daniel Borkmann | f3694e0 | 2016-09-09 02:45:31 +0200 | [diff] [blame] | 2456 | BPF_CALL_5(bpf_xdp_event_output, struct xdp_buff *, xdp, struct bpf_map *, map, |
| 2457 | u64, flags, void *, meta, u64, meta_size) |
Daniel Borkmann | 4de1696 | 2016-08-18 01:00:40 +0200 | [diff] [blame] | 2458 | { |
Daniel Borkmann | 4de1696 | 2016-08-18 01:00:40 +0200 | [diff] [blame] | 2459 | u64 xdp_size = (flags & BPF_F_CTXLEN_MASK) >> 32; |
Daniel Borkmann | 4de1696 | 2016-08-18 01:00:40 +0200 | [diff] [blame] | 2460 | |
| 2461 | if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK))) |
| 2462 | return -EINVAL; |
| 2463 | if (unlikely(xdp_size > (unsigned long)(xdp->data_end - xdp->data))) |
| 2464 | return -EFAULT; |
| 2465 | |
| 2466 | return bpf_event_output(map, flags, meta, meta_size, xdp, xdp_size, |
| 2467 | bpf_xdp_copy); |
| 2468 | } |
| 2469 | |
| 2470 | static const struct bpf_func_proto bpf_xdp_event_output_proto = { |
| 2471 | .func = bpf_xdp_event_output, |
| 2472 | .gpl_only = true, |
| 2473 | .ret_type = RET_INTEGER, |
| 2474 | .arg1_type = ARG_PTR_TO_CTX, |
| 2475 | .arg2_type = ARG_CONST_MAP_PTR, |
| 2476 | .arg3_type = ARG_ANYTHING, |
| 2477 | .arg4_type = ARG_PTR_TO_STACK, |
| 2478 | .arg5_type = ARG_CONST_STACK_SIZE, |
| 2479 | }; |
| 2480 | |
Daniel Borkmann | d4052c4 | 2015-03-01 12:31:45 +0100 | [diff] [blame] | 2481 | static const struct bpf_func_proto * |
| 2482 | sk_filter_func_proto(enum bpf_func_id func_id) |
Alexei Starovoitov | 89aa075 | 2014-12-01 15:06:35 -0800 | [diff] [blame] | 2483 | { |
| 2484 | switch (func_id) { |
| 2485 | case BPF_FUNC_map_lookup_elem: |
| 2486 | return &bpf_map_lookup_elem_proto; |
| 2487 | case BPF_FUNC_map_update_elem: |
| 2488 | return &bpf_map_update_elem_proto; |
| 2489 | case BPF_FUNC_map_delete_elem: |
| 2490 | return &bpf_map_delete_elem_proto; |
Daniel Borkmann | 03e69b5 | 2015-03-14 02:27:16 +0100 | [diff] [blame] | 2491 | case BPF_FUNC_get_prandom_u32: |
| 2492 | return &bpf_get_prandom_u32_proto; |
Daniel Borkmann | c04167c | 2015-03-14 02:27:17 +0100 | [diff] [blame] | 2493 | case BPF_FUNC_get_smp_processor_id: |
Daniel Borkmann | 80b48c4 | 2016-06-28 12:18:26 +0200 | [diff] [blame] | 2494 | return &bpf_get_raw_smp_processor_id_proto; |
Alexei Starovoitov | 04fd61a | 2015-05-19 16:59:03 -0700 | [diff] [blame] | 2495 | case BPF_FUNC_tail_call: |
| 2496 | return &bpf_tail_call_proto; |
Daniel Borkmann | 17ca8cb | 2015-05-29 23:23:06 +0200 | [diff] [blame] | 2497 | case BPF_FUNC_ktime_get_ns: |
| 2498 | return &bpf_ktime_get_ns_proto; |
Alexei Starovoitov | 0756ea3 | 2015-06-12 19:39:13 -0700 | [diff] [blame] | 2499 | case BPF_FUNC_trace_printk: |
Alexei Starovoitov | 1be7f75 | 2015-10-07 22:23:21 -0700 | [diff] [blame] | 2500 | if (capable(CAP_SYS_ADMIN)) |
| 2501 | return bpf_get_trace_printk_proto(); |
Alexei Starovoitov | 89aa075 | 2014-12-01 15:06:35 -0800 | [diff] [blame] | 2502 | default: |
| 2503 | return NULL; |
| 2504 | } |
| 2505 | } |
| 2506 | |
Alexei Starovoitov | 608cd71 | 2015-03-26 19:53:57 -0700 | [diff] [blame] | 2507 | static const struct bpf_func_proto * |
| 2508 | tc_cls_act_func_proto(enum bpf_func_id func_id) |
| 2509 | { |
| 2510 | switch (func_id) { |
| 2511 | case BPF_FUNC_skb_store_bytes: |
| 2512 | return &bpf_skb_store_bytes_proto; |
Daniel Borkmann | 05c74e5 | 2015-12-17 23:51:53 +0100 | [diff] [blame] | 2513 | case BPF_FUNC_skb_load_bytes: |
| 2514 | return &bpf_skb_load_bytes_proto; |
Daniel Borkmann | 36bbef5 | 2016-09-20 00:26:13 +0200 | [diff] [blame] | 2515 | case BPF_FUNC_skb_pull_data: |
| 2516 | return &bpf_skb_pull_data_proto; |
Daniel Borkmann | 7d67234 | 2016-02-19 23:05:23 +0100 | [diff] [blame] | 2517 | case BPF_FUNC_csum_diff: |
| 2518 | return &bpf_csum_diff_proto; |
Daniel Borkmann | 36bbef5 | 2016-09-20 00:26:13 +0200 | [diff] [blame] | 2519 | case BPF_FUNC_csum_update: |
| 2520 | return &bpf_csum_update_proto; |
Alexei Starovoitov | 91bc4822 | 2015-04-01 17:12:13 -0700 | [diff] [blame] | 2521 | case BPF_FUNC_l3_csum_replace: |
| 2522 | return &bpf_l3_csum_replace_proto; |
| 2523 | case BPF_FUNC_l4_csum_replace: |
| 2524 | return &bpf_l4_csum_replace_proto; |
Alexei Starovoitov | 3896d65 | 2015-06-02 16:03:14 -0700 | [diff] [blame] | 2525 | case BPF_FUNC_clone_redirect: |
| 2526 | return &bpf_clone_redirect_proto; |
Daniel Borkmann | 8d20aab | 2015-07-15 14:21:42 +0200 | [diff] [blame] | 2527 | case BPF_FUNC_get_cgroup_classid: |
| 2528 | return &bpf_get_cgroup_classid_proto; |
Alexei Starovoitov | 4e10df9 | 2015-07-20 20:34:18 -0700 | [diff] [blame] | 2529 | case BPF_FUNC_skb_vlan_push: |
| 2530 | return &bpf_skb_vlan_push_proto; |
| 2531 | case BPF_FUNC_skb_vlan_pop: |
| 2532 | return &bpf_skb_vlan_pop_proto; |
Daniel Borkmann | 6578171 | 2016-06-28 12:18:27 +0200 | [diff] [blame] | 2533 | case BPF_FUNC_skb_change_proto: |
| 2534 | return &bpf_skb_change_proto_proto; |
Daniel Borkmann | d2485c4 | 2016-06-28 12:18:28 +0200 | [diff] [blame] | 2535 | case BPF_FUNC_skb_change_type: |
| 2536 | return &bpf_skb_change_type_proto; |
Daniel Borkmann | 5293efe | 2016-08-18 01:00:39 +0200 | [diff] [blame] | 2537 | case BPF_FUNC_skb_change_tail: |
| 2538 | return &bpf_skb_change_tail_proto; |
Alexei Starovoitov | d3aa45c | 2015-07-30 15:36:57 -0700 | [diff] [blame] | 2539 | case BPF_FUNC_skb_get_tunnel_key: |
| 2540 | return &bpf_skb_get_tunnel_key_proto; |
| 2541 | case BPF_FUNC_skb_set_tunnel_key: |
Daniel Borkmann | 14ca075 | 2016-03-04 15:15:06 +0100 | [diff] [blame] | 2542 | return bpf_get_skb_set_tunnel_proto(func_id); |
| 2543 | case BPF_FUNC_skb_get_tunnel_opt: |
| 2544 | return &bpf_skb_get_tunnel_opt_proto; |
| 2545 | case BPF_FUNC_skb_set_tunnel_opt: |
| 2546 | return bpf_get_skb_set_tunnel_proto(func_id); |
Alexei Starovoitov | 27b29f6 | 2015-09-15 23:05:43 -0700 | [diff] [blame] | 2547 | case BPF_FUNC_redirect: |
| 2548 | return &bpf_redirect_proto; |
Daniel Borkmann | c46646d | 2015-09-30 01:41:51 +0200 | [diff] [blame] | 2549 | case BPF_FUNC_get_route_realm: |
| 2550 | return &bpf_get_route_realm_proto; |
Daniel Borkmann | 13c5c24 | 2016-07-03 01:28:47 +0200 | [diff] [blame] | 2551 | case BPF_FUNC_get_hash_recalc: |
| 2552 | return &bpf_get_hash_recalc_proto; |
Daniel Borkmann | 7a4b28c | 2016-09-23 01:28:37 +0200 | [diff] [blame] | 2553 | case BPF_FUNC_set_hash_invalid: |
| 2554 | return &bpf_set_hash_invalid_proto; |
Daniel Borkmann | bd570ff | 2016-04-18 21:01:24 +0200 | [diff] [blame] | 2555 | case BPF_FUNC_perf_event_output: |
Daniel Borkmann | 555c8a8 | 2016-07-14 18:08:05 +0200 | [diff] [blame] | 2556 | return &bpf_skb_event_output_proto; |
Daniel Borkmann | 80b48c4 | 2016-06-28 12:18:26 +0200 | [diff] [blame] | 2557 | case BPF_FUNC_get_smp_processor_id: |
| 2558 | return &bpf_get_smp_processor_id_proto; |
Daniel Borkmann | 747ea55 | 2016-08-12 22:17:17 +0200 | [diff] [blame] | 2559 | case BPF_FUNC_skb_under_cgroup: |
| 2560 | return &bpf_skb_under_cgroup_proto; |
Alexei Starovoitov | 608cd71 | 2015-03-26 19:53:57 -0700 | [diff] [blame] | 2561 | default: |
| 2562 | return sk_filter_func_proto(func_id); |
| 2563 | } |
| 2564 | } |
| 2565 | |
Brenden Blanco | 6a773a1 | 2016-07-19 12:16:47 -0700 | [diff] [blame] | 2566 | static const struct bpf_func_proto * |
| 2567 | xdp_func_proto(enum bpf_func_id func_id) |
| 2568 | { |
Daniel Borkmann | 4de1696 | 2016-08-18 01:00:40 +0200 | [diff] [blame] | 2569 | switch (func_id) { |
| 2570 | case BPF_FUNC_perf_event_output: |
| 2571 | return &bpf_xdp_event_output_proto; |
Daniel Borkmann | 669dc4d | 2016-09-23 01:28:36 +0200 | [diff] [blame] | 2572 | case BPF_FUNC_get_smp_processor_id: |
| 2573 | return &bpf_get_smp_processor_id_proto; |
Daniel Borkmann | 4de1696 | 2016-08-18 01:00:40 +0200 | [diff] [blame] | 2574 | default: |
| 2575 | return sk_filter_func_proto(func_id); |
| 2576 | } |
Brenden Blanco | 6a773a1 | 2016-07-19 12:16:47 -0700 | [diff] [blame] | 2577 | } |
| 2578 | |
Alexei Starovoitov | d691f9e | 2015-06-04 10:11:54 -0700 | [diff] [blame] | 2579 | static bool __is_valid_access(int off, int size, enum bpf_access_type type) |
Alexei Starovoitov | 89aa075 | 2014-12-01 15:06:35 -0800 | [diff] [blame] | 2580 | { |
Alexei Starovoitov | 9bac3d6 | 2015-03-13 11:57:42 -0700 | [diff] [blame] | 2581 | if (off < 0 || off >= sizeof(struct __sk_buff)) |
| 2582 | return false; |
Daniel Borkmann | 4936e35 | 2016-05-13 19:08:26 +0200 | [diff] [blame] | 2583 | /* The verifier guarantees that size > 0. */ |
Alexei Starovoitov | 9bac3d6 | 2015-03-13 11:57:42 -0700 | [diff] [blame] | 2584 | if (off % size != 0) |
| 2585 | return false; |
Daniel Borkmann | 4936e35 | 2016-05-13 19:08:26 +0200 | [diff] [blame] | 2586 | if (size != sizeof(__u32)) |
Alexei Starovoitov | 9bac3d6 | 2015-03-13 11:57:42 -0700 | [diff] [blame] | 2587 | return false; |
| 2588 | |
| 2589 | return true; |
| 2590 | } |
| 2591 | |
Alexei Starovoitov | d691f9e | 2015-06-04 10:11:54 -0700 | [diff] [blame] | 2592 | static bool sk_filter_is_valid_access(int off, int size, |
Alexei Starovoitov | 19de99f | 2016-06-15 18:25:38 -0700 | [diff] [blame] | 2593 | enum bpf_access_type type, |
| 2594 | enum bpf_reg_type *reg_type) |
Alexei Starovoitov | d691f9e | 2015-06-04 10:11:54 -0700 | [diff] [blame] | 2595 | { |
Alexei Starovoitov | db58ba4 | 2016-05-05 19:49:12 -0700 | [diff] [blame] | 2596 | switch (off) { |
| 2597 | case offsetof(struct __sk_buff, tc_classid): |
| 2598 | case offsetof(struct __sk_buff, data): |
| 2599 | case offsetof(struct __sk_buff, data_end): |
Daniel Borkmann | 045efa8 | 2015-09-15 23:05:42 -0700 | [diff] [blame] | 2600 | return false; |
Alexei Starovoitov | db58ba4 | 2016-05-05 19:49:12 -0700 | [diff] [blame] | 2601 | } |
Daniel Borkmann | 045efa8 | 2015-09-15 23:05:42 -0700 | [diff] [blame] | 2602 | |
Alexei Starovoitov | d691f9e | 2015-06-04 10:11:54 -0700 | [diff] [blame] | 2603 | if (type == BPF_WRITE) { |
| 2604 | switch (off) { |
| 2605 | case offsetof(struct __sk_buff, cb[0]) ... |
Daniel Borkmann | 4936e35 | 2016-05-13 19:08:26 +0200 | [diff] [blame] | 2606 | offsetof(struct __sk_buff, cb[4]): |
Alexei Starovoitov | d691f9e | 2015-06-04 10:11:54 -0700 | [diff] [blame] | 2607 | break; |
| 2608 | default: |
| 2609 | return false; |
| 2610 | } |
| 2611 | } |
| 2612 | |
| 2613 | return __is_valid_access(off, size, type); |
| 2614 | } |
| 2615 | |
Daniel Borkmann | 36bbef5 | 2016-09-20 00:26:13 +0200 | [diff] [blame] | 2616 | static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write, |
| 2617 | const struct bpf_prog *prog) |
| 2618 | { |
| 2619 | struct bpf_insn *insn = insn_buf; |
| 2620 | |
| 2621 | if (!direct_write) |
| 2622 | return 0; |
| 2623 | |
| 2624 | /* if (!skb->cloned) |
| 2625 | * goto start; |
| 2626 | * |
| 2627 | * (Fast-path, otherwise approximation that we might be |
| 2628 | * a clone, do the rest in helper.) |
| 2629 | */ |
| 2630 | *insn++ = BPF_LDX_MEM(BPF_B, BPF_REG_6, BPF_REG_1, CLONED_OFFSET()); |
| 2631 | *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_6, CLONED_MASK); |
| 2632 | *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 7); |
| 2633 | |
| 2634 | /* ret = bpf_skb_pull_data(skb, 0); */ |
| 2635 | *insn++ = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1); |
| 2636 | *insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_2, BPF_REG_2); |
| 2637 | *insn++ = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, |
| 2638 | BPF_FUNC_skb_pull_data); |
| 2639 | /* if (!ret) |
| 2640 | * goto restore; |
| 2641 | * return TC_ACT_SHOT; |
| 2642 | */ |
| 2643 | *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2); |
| 2644 | *insn++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, TC_ACT_SHOT); |
| 2645 | *insn++ = BPF_EXIT_INSN(); |
| 2646 | |
| 2647 | /* restore: */ |
| 2648 | *insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6); |
| 2649 | /* start: */ |
| 2650 | *insn++ = prog->insnsi[0]; |
| 2651 | |
| 2652 | return insn - insn_buf; |
| 2653 | } |
| 2654 | |
Alexei Starovoitov | d691f9e | 2015-06-04 10:11:54 -0700 | [diff] [blame] | 2655 | static bool tc_cls_act_is_valid_access(int off, int size, |
Alexei Starovoitov | 19de99f | 2016-06-15 18:25:38 -0700 | [diff] [blame] | 2656 | enum bpf_access_type type, |
| 2657 | enum bpf_reg_type *reg_type) |
Alexei Starovoitov | d691f9e | 2015-06-04 10:11:54 -0700 | [diff] [blame] | 2658 | { |
| 2659 | if (type == BPF_WRITE) { |
| 2660 | switch (off) { |
| 2661 | case offsetof(struct __sk_buff, mark): |
| 2662 | case offsetof(struct __sk_buff, tc_index): |
Daniel Borkmann | 754f1e6 | 2015-09-30 01:41:52 +0200 | [diff] [blame] | 2663 | case offsetof(struct __sk_buff, priority): |
Alexei Starovoitov | d691f9e | 2015-06-04 10:11:54 -0700 | [diff] [blame] | 2664 | case offsetof(struct __sk_buff, cb[0]) ... |
Daniel Borkmann | 09c37a2 | 2016-03-16 01:42:49 +0100 | [diff] [blame] | 2665 | offsetof(struct __sk_buff, cb[4]): |
| 2666 | case offsetof(struct __sk_buff, tc_classid): |
Alexei Starovoitov | d691f9e | 2015-06-04 10:11:54 -0700 | [diff] [blame] | 2667 | break; |
| 2668 | default: |
| 2669 | return false; |
| 2670 | } |
| 2671 | } |
Alexei Starovoitov | 19de99f | 2016-06-15 18:25:38 -0700 | [diff] [blame] | 2672 | |
| 2673 | switch (off) { |
| 2674 | case offsetof(struct __sk_buff, data): |
| 2675 | *reg_type = PTR_TO_PACKET; |
| 2676 | break; |
| 2677 | case offsetof(struct __sk_buff, data_end): |
| 2678 | *reg_type = PTR_TO_PACKET_END; |
| 2679 | break; |
| 2680 | } |
| 2681 | |
Alexei Starovoitov | d691f9e | 2015-06-04 10:11:54 -0700 | [diff] [blame] | 2682 | return __is_valid_access(off, size, type); |
| 2683 | } |
| 2684 | |
Brenden Blanco | 6a773a1 | 2016-07-19 12:16:47 -0700 | [diff] [blame] | 2685 | static bool __is_valid_xdp_access(int off, int size, |
| 2686 | enum bpf_access_type type) |
| 2687 | { |
| 2688 | if (off < 0 || off >= sizeof(struct xdp_md)) |
| 2689 | return false; |
| 2690 | if (off % size != 0) |
| 2691 | return false; |
Daniel Borkmann | 6088b58 | 2016-09-09 02:45:28 +0200 | [diff] [blame] | 2692 | if (size != sizeof(__u32)) |
Brenden Blanco | 6a773a1 | 2016-07-19 12:16:47 -0700 | [diff] [blame] | 2693 | return false; |
| 2694 | |
| 2695 | return true; |
| 2696 | } |
| 2697 | |
| 2698 | static bool xdp_is_valid_access(int off, int size, |
| 2699 | enum bpf_access_type type, |
| 2700 | enum bpf_reg_type *reg_type) |
| 2701 | { |
| 2702 | if (type == BPF_WRITE) |
| 2703 | return false; |
| 2704 | |
| 2705 | switch (off) { |
| 2706 | case offsetof(struct xdp_md, data): |
| 2707 | *reg_type = PTR_TO_PACKET; |
| 2708 | break; |
| 2709 | case offsetof(struct xdp_md, data_end): |
| 2710 | *reg_type = PTR_TO_PACKET_END; |
| 2711 | break; |
| 2712 | } |
| 2713 | |
| 2714 | return __is_valid_xdp_access(off, size, type); |
| 2715 | } |
| 2716 | |
| 2717 | void bpf_warn_invalid_xdp_action(u32 act) |
| 2718 | { |
| 2719 | WARN_ONCE(1, "Illegal XDP return value %u, expect packet loss\n", act); |
| 2720 | } |
| 2721 | EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action); |
| 2722 | |
Daniel Borkmann | 374fb54 | 2016-09-09 02:45:30 +0200 | [diff] [blame] | 2723 | static u32 sk_filter_convert_ctx_access(enum bpf_access_type type, int dst_reg, |
| 2724 | int src_reg, int ctx_off, |
| 2725 | struct bpf_insn *insn_buf, |
| 2726 | struct bpf_prog *prog) |
Alexei Starovoitov | 9bac3d6 | 2015-03-13 11:57:42 -0700 | [diff] [blame] | 2727 | { |
| 2728 | struct bpf_insn *insn = insn_buf; |
| 2729 | |
| 2730 | switch (ctx_off) { |
| 2731 | case offsetof(struct __sk_buff, len): |
| 2732 | BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, len) != 4); |
| 2733 | |
| 2734 | *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg, |
| 2735 | offsetof(struct sk_buff, len)); |
| 2736 | break; |
| 2737 | |
Daniel Borkmann | 0b8c707 | 2015-03-19 19:38:27 +0100 | [diff] [blame] | 2738 | case offsetof(struct __sk_buff, protocol): |
| 2739 | BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, protocol) != 2); |
| 2740 | |
| 2741 | *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg, |
| 2742 | offsetof(struct sk_buff, protocol)); |
| 2743 | break; |
| 2744 | |
Michal Sekletar | 27cd545 | 2015-03-24 14:48:41 +0100 | [diff] [blame] | 2745 | case offsetof(struct __sk_buff, vlan_proto): |
| 2746 | BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_proto) != 2); |
| 2747 | |
| 2748 | *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg, |
| 2749 | offsetof(struct sk_buff, vlan_proto)); |
| 2750 | break; |
| 2751 | |
Daniel Borkmann | bcad571 | 2015-04-03 20:52:24 +0200 | [diff] [blame] | 2752 | case offsetof(struct __sk_buff, priority): |
| 2753 | BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, priority) != 4); |
| 2754 | |
Daniel Borkmann | 754f1e6 | 2015-09-30 01:41:52 +0200 | [diff] [blame] | 2755 | if (type == BPF_WRITE) |
| 2756 | *insn++ = BPF_STX_MEM(BPF_W, dst_reg, src_reg, |
| 2757 | offsetof(struct sk_buff, priority)); |
| 2758 | else |
| 2759 | *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg, |
| 2760 | offsetof(struct sk_buff, priority)); |
Daniel Borkmann | bcad571 | 2015-04-03 20:52:24 +0200 | [diff] [blame] | 2761 | break; |
| 2762 | |
Alexei Starovoitov | 37e82c2 | 2015-05-27 15:30:39 -0700 | [diff] [blame] | 2763 | case offsetof(struct __sk_buff, ingress_ifindex): |
| 2764 | BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, skb_iif) != 4); |
| 2765 | |
| 2766 | *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg, |
| 2767 | offsetof(struct sk_buff, skb_iif)); |
| 2768 | break; |
| 2769 | |
| 2770 | case offsetof(struct __sk_buff, ifindex): |
| 2771 | BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, ifindex) != 4); |
| 2772 | |
Daniel Borkmann | f035a51 | 2016-09-09 02:45:29 +0200 | [diff] [blame] | 2773 | *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev), |
Alexei Starovoitov | 37e82c2 | 2015-05-27 15:30:39 -0700 | [diff] [blame] | 2774 | dst_reg, src_reg, |
| 2775 | offsetof(struct sk_buff, dev)); |
| 2776 | *insn++ = BPF_JMP_IMM(BPF_JEQ, dst_reg, 0, 1); |
| 2777 | *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, dst_reg, |
| 2778 | offsetof(struct net_device, ifindex)); |
| 2779 | break; |
| 2780 | |
Daniel Borkmann | ba7591d | 2015-08-01 00:46:29 +0200 | [diff] [blame] | 2781 | case offsetof(struct __sk_buff, hash): |
| 2782 | BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, hash) != 4); |
| 2783 | |
| 2784 | *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg, |
| 2785 | offsetof(struct sk_buff, hash)); |
| 2786 | break; |
| 2787 | |
Alexei Starovoitov | 9bac3d6 | 2015-03-13 11:57:42 -0700 | [diff] [blame] | 2788 | case offsetof(struct __sk_buff, mark): |
Alexei Starovoitov | d691f9e | 2015-06-04 10:11:54 -0700 | [diff] [blame] | 2789 | BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, mark) != 4); |
| 2790 | |
| 2791 | if (type == BPF_WRITE) |
| 2792 | *insn++ = BPF_STX_MEM(BPF_W, dst_reg, src_reg, |
| 2793 | offsetof(struct sk_buff, mark)); |
| 2794 | else |
| 2795 | *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg, |
| 2796 | offsetof(struct sk_buff, mark)); |
| 2797 | break; |
Alexei Starovoitov | 9bac3d6 | 2015-03-13 11:57:42 -0700 | [diff] [blame] | 2798 | |
| 2799 | case offsetof(struct __sk_buff, pkt_type): |
| 2800 | return convert_skb_access(SKF_AD_PKTTYPE, dst_reg, src_reg, insn); |
| 2801 | |
| 2802 | case offsetof(struct __sk_buff, queue_mapping): |
| 2803 | return convert_skb_access(SKF_AD_QUEUE, dst_reg, src_reg, insn); |
Alexei Starovoitov | c249739 | 2015-03-16 18:06:02 -0700 | [diff] [blame] | 2804 | |
Alexei Starovoitov | c249739 | 2015-03-16 18:06:02 -0700 | [diff] [blame] | 2805 | case offsetof(struct __sk_buff, vlan_present): |
| 2806 | return convert_skb_access(SKF_AD_VLAN_TAG_PRESENT, |
| 2807 | dst_reg, src_reg, insn); |
| 2808 | |
| 2809 | case offsetof(struct __sk_buff, vlan_tci): |
| 2810 | return convert_skb_access(SKF_AD_VLAN_TAG, |
| 2811 | dst_reg, src_reg, insn); |
Alexei Starovoitov | d691f9e | 2015-06-04 10:11:54 -0700 | [diff] [blame] | 2812 | |
| 2813 | case offsetof(struct __sk_buff, cb[0]) ... |
Daniel Borkmann | 6088b58 | 2016-09-09 02:45:28 +0200 | [diff] [blame] | 2814 | offsetof(struct __sk_buff, cb[4]): |
Alexei Starovoitov | d691f9e | 2015-06-04 10:11:54 -0700 | [diff] [blame] | 2815 | BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, data) < 20); |
| 2816 | |
Alexei Starovoitov | ff936a0 | 2015-10-07 10:55:41 -0700 | [diff] [blame] | 2817 | prog->cb_access = 1; |
Alexei Starovoitov | d691f9e | 2015-06-04 10:11:54 -0700 | [diff] [blame] | 2818 | ctx_off -= offsetof(struct __sk_buff, cb[0]); |
| 2819 | ctx_off += offsetof(struct sk_buff, cb); |
| 2820 | ctx_off += offsetof(struct qdisc_skb_cb, data); |
| 2821 | if (type == BPF_WRITE) |
| 2822 | *insn++ = BPF_STX_MEM(BPF_W, dst_reg, src_reg, ctx_off); |
| 2823 | else |
| 2824 | *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg, ctx_off); |
| 2825 | break; |
| 2826 | |
Daniel Borkmann | 045efa8 | 2015-09-15 23:05:42 -0700 | [diff] [blame] | 2827 | case offsetof(struct __sk_buff, tc_classid): |
| 2828 | ctx_off -= offsetof(struct __sk_buff, tc_classid); |
| 2829 | ctx_off += offsetof(struct sk_buff, cb); |
| 2830 | ctx_off += offsetof(struct qdisc_skb_cb, tc_classid); |
Daniel Borkmann | 09c37a2 | 2016-03-16 01:42:49 +0100 | [diff] [blame] | 2831 | if (type == BPF_WRITE) |
| 2832 | *insn++ = BPF_STX_MEM(BPF_H, dst_reg, src_reg, ctx_off); |
| 2833 | else |
| 2834 | *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg, ctx_off); |
Daniel Borkmann | 045efa8 | 2015-09-15 23:05:42 -0700 | [diff] [blame] | 2835 | break; |
| 2836 | |
Alexei Starovoitov | db58ba4 | 2016-05-05 19:49:12 -0700 | [diff] [blame] | 2837 | case offsetof(struct __sk_buff, data): |
Daniel Borkmann | f035a51 | 2016-09-09 02:45:29 +0200 | [diff] [blame] | 2838 | *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data), |
Alexei Starovoitov | db58ba4 | 2016-05-05 19:49:12 -0700 | [diff] [blame] | 2839 | dst_reg, src_reg, |
| 2840 | offsetof(struct sk_buff, data)); |
| 2841 | break; |
| 2842 | |
| 2843 | case offsetof(struct __sk_buff, data_end): |
| 2844 | ctx_off -= offsetof(struct __sk_buff, data_end); |
| 2845 | ctx_off += offsetof(struct sk_buff, cb); |
| 2846 | ctx_off += offsetof(struct bpf_skb_data_end, data_end); |
Daniel Borkmann | f035a51 | 2016-09-09 02:45:29 +0200 | [diff] [blame] | 2847 | *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), dst_reg, src_reg, |
| 2848 | ctx_off); |
Alexei Starovoitov | db58ba4 | 2016-05-05 19:49:12 -0700 | [diff] [blame] | 2849 | break; |
| 2850 | |
Alexei Starovoitov | d691f9e | 2015-06-04 10:11:54 -0700 | [diff] [blame] | 2851 | case offsetof(struct __sk_buff, tc_index): |
| 2852 | #ifdef CONFIG_NET_SCHED |
| 2853 | BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, tc_index) != 2); |
| 2854 | |
| 2855 | if (type == BPF_WRITE) |
| 2856 | *insn++ = BPF_STX_MEM(BPF_H, dst_reg, src_reg, |
| 2857 | offsetof(struct sk_buff, tc_index)); |
| 2858 | else |
| 2859 | *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg, |
| 2860 | offsetof(struct sk_buff, tc_index)); |
| 2861 | break; |
| 2862 | #else |
| 2863 | if (type == BPF_WRITE) |
| 2864 | *insn++ = BPF_MOV64_REG(dst_reg, dst_reg); |
| 2865 | else |
| 2866 | *insn++ = BPF_MOV64_IMM(dst_reg, 0); |
| 2867 | break; |
| 2868 | #endif |
Alexei Starovoitov | 9bac3d6 | 2015-03-13 11:57:42 -0700 | [diff] [blame] | 2869 | } |
| 2870 | |
| 2871 | return insn - insn_buf; |
Alexei Starovoitov | 89aa075 | 2014-12-01 15:06:35 -0800 | [diff] [blame] | 2872 | } |
| 2873 | |
Daniel Borkmann | 374fb54 | 2016-09-09 02:45:30 +0200 | [diff] [blame] | 2874 | static u32 tc_cls_act_convert_ctx_access(enum bpf_access_type type, int dst_reg, |
| 2875 | int src_reg, int ctx_off, |
| 2876 | struct bpf_insn *insn_buf, |
| 2877 | struct bpf_prog *prog) |
| 2878 | { |
| 2879 | struct bpf_insn *insn = insn_buf; |
| 2880 | |
| 2881 | switch (ctx_off) { |
| 2882 | case offsetof(struct __sk_buff, ifindex): |
| 2883 | BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, ifindex) != 4); |
| 2884 | |
| 2885 | *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev), |
| 2886 | dst_reg, src_reg, |
| 2887 | offsetof(struct sk_buff, dev)); |
| 2888 | *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, dst_reg, |
| 2889 | offsetof(struct net_device, ifindex)); |
| 2890 | break; |
| 2891 | default: |
| 2892 | return sk_filter_convert_ctx_access(type, dst_reg, src_reg, |
| 2893 | ctx_off, insn_buf, prog); |
| 2894 | } |
| 2895 | |
| 2896 | return insn - insn_buf; |
| 2897 | } |
| 2898 | |
Brenden Blanco | 6a773a1 | 2016-07-19 12:16:47 -0700 | [diff] [blame] | 2899 | static u32 xdp_convert_ctx_access(enum bpf_access_type type, int dst_reg, |
| 2900 | int src_reg, int ctx_off, |
| 2901 | struct bpf_insn *insn_buf, |
| 2902 | struct bpf_prog *prog) |
| 2903 | { |
| 2904 | struct bpf_insn *insn = insn_buf; |
| 2905 | |
| 2906 | switch (ctx_off) { |
| 2907 | case offsetof(struct xdp_md, data): |
Daniel Borkmann | f035a51 | 2016-09-09 02:45:29 +0200 | [diff] [blame] | 2908 | *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data), |
Brenden Blanco | 6a773a1 | 2016-07-19 12:16:47 -0700 | [diff] [blame] | 2909 | dst_reg, src_reg, |
| 2910 | offsetof(struct xdp_buff, data)); |
| 2911 | break; |
| 2912 | case offsetof(struct xdp_md, data_end): |
Daniel Borkmann | f035a51 | 2016-09-09 02:45:29 +0200 | [diff] [blame] | 2913 | *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_end), |
Brenden Blanco | 6a773a1 | 2016-07-19 12:16:47 -0700 | [diff] [blame] | 2914 | dst_reg, src_reg, |
| 2915 | offsetof(struct xdp_buff, data_end)); |
| 2916 | break; |
| 2917 | } |
| 2918 | |
| 2919 | return insn - insn_buf; |
| 2920 | } |
| 2921 | |
Daniel Borkmann | d4052c4 | 2015-03-01 12:31:45 +0100 | [diff] [blame] | 2922 | static const struct bpf_verifier_ops sk_filter_ops = { |
Daniel Borkmann | 4936e35 | 2016-05-13 19:08:26 +0200 | [diff] [blame] | 2923 | .get_func_proto = sk_filter_func_proto, |
| 2924 | .is_valid_access = sk_filter_is_valid_access, |
Daniel Borkmann | 374fb54 | 2016-09-09 02:45:30 +0200 | [diff] [blame] | 2925 | .convert_ctx_access = sk_filter_convert_ctx_access, |
Alexei Starovoitov | 89aa075 | 2014-12-01 15:06:35 -0800 | [diff] [blame] | 2926 | }; |
| 2927 | |
Alexei Starovoitov | 608cd71 | 2015-03-26 19:53:57 -0700 | [diff] [blame] | 2928 | static const struct bpf_verifier_ops tc_cls_act_ops = { |
Daniel Borkmann | 4936e35 | 2016-05-13 19:08:26 +0200 | [diff] [blame] | 2929 | .get_func_proto = tc_cls_act_func_proto, |
| 2930 | .is_valid_access = tc_cls_act_is_valid_access, |
Daniel Borkmann | 374fb54 | 2016-09-09 02:45:30 +0200 | [diff] [blame] | 2931 | .convert_ctx_access = tc_cls_act_convert_ctx_access, |
Daniel Borkmann | 36bbef5 | 2016-09-20 00:26:13 +0200 | [diff] [blame] | 2932 | .gen_prologue = tc_cls_act_prologue, |
Alexei Starovoitov | 608cd71 | 2015-03-26 19:53:57 -0700 | [diff] [blame] | 2933 | }; |
| 2934 | |
Brenden Blanco | 6a773a1 | 2016-07-19 12:16:47 -0700 | [diff] [blame] | 2935 | static const struct bpf_verifier_ops xdp_ops = { |
| 2936 | .get_func_proto = xdp_func_proto, |
| 2937 | .is_valid_access = xdp_is_valid_access, |
| 2938 | .convert_ctx_access = xdp_convert_ctx_access, |
| 2939 | }; |
| 2940 | |
Daniel Borkmann | d4052c4 | 2015-03-01 12:31:45 +0100 | [diff] [blame] | 2941 | static struct bpf_prog_type_list sk_filter_type __read_mostly = { |
Daniel Borkmann | 4936e35 | 2016-05-13 19:08:26 +0200 | [diff] [blame] | 2942 | .ops = &sk_filter_ops, |
| 2943 | .type = BPF_PROG_TYPE_SOCKET_FILTER, |
Alexei Starovoitov | 89aa075 | 2014-12-01 15:06:35 -0800 | [diff] [blame] | 2944 | }; |
| 2945 | |
Daniel Borkmann | 96be432 | 2015-03-01 12:31:46 +0100 | [diff] [blame] | 2946 | static struct bpf_prog_type_list sched_cls_type __read_mostly = { |
Daniel Borkmann | 4936e35 | 2016-05-13 19:08:26 +0200 | [diff] [blame] | 2947 | .ops = &tc_cls_act_ops, |
| 2948 | .type = BPF_PROG_TYPE_SCHED_CLS, |
Daniel Borkmann | 96be432 | 2015-03-01 12:31:46 +0100 | [diff] [blame] | 2949 | }; |
| 2950 | |
Daniel Borkmann | 94caee8 | 2015-03-20 15:11:11 +0100 | [diff] [blame] | 2951 | static struct bpf_prog_type_list sched_act_type __read_mostly = { |
Daniel Borkmann | 4936e35 | 2016-05-13 19:08:26 +0200 | [diff] [blame] | 2952 | .ops = &tc_cls_act_ops, |
| 2953 | .type = BPF_PROG_TYPE_SCHED_ACT, |
Daniel Borkmann | 94caee8 | 2015-03-20 15:11:11 +0100 | [diff] [blame] | 2954 | }; |
| 2955 | |
Brenden Blanco | 6a773a1 | 2016-07-19 12:16:47 -0700 | [diff] [blame] | 2956 | static struct bpf_prog_type_list xdp_type __read_mostly = { |
| 2957 | .ops = &xdp_ops, |
| 2958 | .type = BPF_PROG_TYPE_XDP, |
| 2959 | }; |
| 2960 | |
Daniel Borkmann | d4052c4 | 2015-03-01 12:31:45 +0100 | [diff] [blame] | 2961 | static int __init register_sk_filter_ops(void) |
Alexei Starovoitov | 89aa075 | 2014-12-01 15:06:35 -0800 | [diff] [blame] | 2962 | { |
Daniel Borkmann | d4052c4 | 2015-03-01 12:31:45 +0100 | [diff] [blame] | 2963 | bpf_register_prog_type(&sk_filter_type); |
Daniel Borkmann | 96be432 | 2015-03-01 12:31:46 +0100 | [diff] [blame] | 2964 | bpf_register_prog_type(&sched_cls_type); |
Daniel Borkmann | 94caee8 | 2015-03-20 15:11:11 +0100 | [diff] [blame] | 2965 | bpf_register_prog_type(&sched_act_type); |
Brenden Blanco | 6a773a1 | 2016-07-19 12:16:47 -0700 | [diff] [blame] | 2966 | bpf_register_prog_type(&xdp_type); |
Daniel Borkmann | 96be432 | 2015-03-01 12:31:46 +0100 | [diff] [blame] | 2967 | |
Alexei Starovoitov | 89aa075 | 2014-12-01 15:06:35 -0800 | [diff] [blame] | 2968 | return 0; |
| 2969 | } |
Daniel Borkmann | d4052c4 | 2015-03-01 12:31:45 +0100 | [diff] [blame] | 2970 | late_initcall(register_sk_filter_ops); |
| 2971 | |
Hannes Frederic Sowa | 8ced425 | 2016-04-05 17:10:16 +0200 | [diff] [blame] | 2972 | int sk_detach_filter(struct sock *sk) |
Pavel Emelyanov | 55b3332 | 2007-10-17 21:21:26 -0700 | [diff] [blame] | 2973 | { |
| 2974 | int ret = -ENOENT; |
| 2975 | struct sk_filter *filter; |
| 2976 | |
Vincent Bernat | d59577b | 2013-01-16 22:55:49 +0100 | [diff] [blame] | 2977 | if (sock_flag(sk, SOCK_FILTER_LOCKED)) |
| 2978 | return -EPERM; |
| 2979 | |
Hannes Frederic Sowa | 8ced425 | 2016-04-05 17:10:16 +0200 | [diff] [blame] | 2980 | filter = rcu_dereference_protected(sk->sk_filter, |
| 2981 | lockdep_sock_is_held(sk)); |
Pavel Emelyanov | 55b3332 | 2007-10-17 21:21:26 -0700 | [diff] [blame] | 2982 | if (filter) { |
Stephen Hemminger | a9b3cd7 | 2011-08-01 16:19:00 +0000 | [diff] [blame] | 2983 | RCU_INIT_POINTER(sk->sk_filter, NULL); |
Eric Dumazet | 46bcf14 | 2010-12-06 09:29:43 -0800 | [diff] [blame] | 2984 | sk_filter_uncharge(sk, filter); |
Pavel Emelyanov | 55b3332 | 2007-10-17 21:21:26 -0700 | [diff] [blame] | 2985 | ret = 0; |
| 2986 | } |
Daniel Borkmann | a3ea269 | 2014-03-28 18:58:19 +0100 | [diff] [blame] | 2987 | |
Pavel Emelyanov | 55b3332 | 2007-10-17 21:21:26 -0700 | [diff] [blame] | 2988 | return ret; |
| 2989 | } |
Hannes Frederic Sowa | 8ced425 | 2016-04-05 17:10:16 +0200 | [diff] [blame] | 2990 | EXPORT_SYMBOL_GPL(sk_detach_filter); |
Pavel Emelyanov | a8fc927 | 2012-11-01 02:01:48 +0000 | [diff] [blame] | 2991 | |
Daniel Borkmann | a3ea269 | 2014-03-28 18:58:19 +0100 | [diff] [blame] | 2992 | int sk_get_filter(struct sock *sk, struct sock_filter __user *ubuf, |
| 2993 | unsigned int len) |
Pavel Emelyanov | a8fc927 | 2012-11-01 02:01:48 +0000 | [diff] [blame] | 2994 | { |
Daniel Borkmann | a3ea269 | 2014-03-28 18:58:19 +0100 | [diff] [blame] | 2995 | struct sock_fprog_kern *fprog; |
Pavel Emelyanov | a8fc927 | 2012-11-01 02:01:48 +0000 | [diff] [blame] | 2996 | struct sk_filter *filter; |
Daniel Borkmann | a3ea269 | 2014-03-28 18:58:19 +0100 | [diff] [blame] | 2997 | int ret = 0; |
Pavel Emelyanov | a8fc927 | 2012-11-01 02:01:48 +0000 | [diff] [blame] | 2998 | |
| 2999 | lock_sock(sk); |
| 3000 | filter = rcu_dereference_protected(sk->sk_filter, |
Hannes Frederic Sowa | 8ced425 | 2016-04-05 17:10:16 +0200 | [diff] [blame] | 3001 | lockdep_sock_is_held(sk)); |
Pavel Emelyanov | a8fc927 | 2012-11-01 02:01:48 +0000 | [diff] [blame] | 3002 | if (!filter) |
| 3003 | goto out; |
Daniel Borkmann | a3ea269 | 2014-03-28 18:58:19 +0100 | [diff] [blame] | 3004 | |
| 3005 | /* We're copying the filter that has been originally attached, |
Daniel Borkmann | 93d08b6 | 2015-10-02 12:06:03 +0200 | [diff] [blame] | 3006 | * so no conversion/decode needed anymore. eBPF programs that |
| 3007 | * have no original program cannot be dumped through this. |
Daniel Borkmann | a3ea269 | 2014-03-28 18:58:19 +0100 | [diff] [blame] | 3008 | */ |
Daniel Borkmann | 93d08b6 | 2015-10-02 12:06:03 +0200 | [diff] [blame] | 3009 | ret = -EACCES; |
Alexei Starovoitov | 7ae457c | 2014-07-30 20:34:16 -0700 | [diff] [blame] | 3010 | fprog = filter->prog->orig_prog; |
Daniel Borkmann | 93d08b6 | 2015-10-02 12:06:03 +0200 | [diff] [blame] | 3011 | if (!fprog) |
| 3012 | goto out; |
Daniel Borkmann | a3ea269 | 2014-03-28 18:58:19 +0100 | [diff] [blame] | 3013 | |
| 3014 | ret = fprog->len; |
Pavel Emelyanov | a8fc927 | 2012-11-01 02:01:48 +0000 | [diff] [blame] | 3015 | if (!len) |
Daniel Borkmann | a3ea269 | 2014-03-28 18:58:19 +0100 | [diff] [blame] | 3016 | /* User space only enquires number of filter blocks. */ |
Pavel Emelyanov | a8fc927 | 2012-11-01 02:01:48 +0000 | [diff] [blame] | 3017 | goto out; |
Daniel Borkmann | a3ea269 | 2014-03-28 18:58:19 +0100 | [diff] [blame] | 3018 | |
Pavel Emelyanov | a8fc927 | 2012-11-01 02:01:48 +0000 | [diff] [blame] | 3019 | ret = -EINVAL; |
Daniel Borkmann | a3ea269 | 2014-03-28 18:58:19 +0100 | [diff] [blame] | 3020 | if (len < fprog->len) |
Pavel Emelyanov | a8fc927 | 2012-11-01 02:01:48 +0000 | [diff] [blame] | 3021 | goto out; |
| 3022 | |
| 3023 | ret = -EFAULT; |
Alexei Starovoitov | 009937e | 2014-07-30 20:34:13 -0700 | [diff] [blame] | 3024 | if (copy_to_user(ubuf, fprog->filter, bpf_classic_proglen(fprog))) |
Daniel Borkmann | a3ea269 | 2014-03-28 18:58:19 +0100 | [diff] [blame] | 3025 | goto out; |
Pavel Emelyanov | a8fc927 | 2012-11-01 02:01:48 +0000 | [diff] [blame] | 3026 | |
Daniel Borkmann | a3ea269 | 2014-03-28 18:58:19 +0100 | [diff] [blame] | 3027 | /* Instead of bytes, the API requests to return the number |
| 3028 | * of filter blocks. |
| 3029 | */ |
| 3030 | ret = fprog->len; |
Pavel Emelyanov | a8fc927 | 2012-11-01 02:01:48 +0000 | [diff] [blame] | 3031 | out: |
| 3032 | release_sock(sk); |
| 3033 | return ret; |
| 3034 | } |