Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 1 | /* |
| 2 | * IPv6 fragment reassembly for connection tracking |
| 3 | * |
| 4 | * Copyright (C)2004 USAGI/WIDE Project |
| 5 | * |
| 6 | * Author: |
| 7 | * Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp> |
| 8 | * |
| 9 | * Based on: net/ipv6/reassembly.c |
| 10 | * |
| 11 | * This program is free software; you can redistribute it and/or |
| 12 | * modify it under the terms of the GNU General Public License |
| 13 | * as published by the Free Software Foundation; either version |
| 14 | * 2 of the License, or (at your option) any later version. |
| 15 | */ |
| 16 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 17 | #include <linux/errno.h> |
| 18 | #include <linux/types.h> |
| 19 | #include <linux/string.h> |
| 20 | #include <linux/socket.h> |
| 21 | #include <linux/sockios.h> |
| 22 | #include <linux/jiffies.h> |
| 23 | #include <linux/net.h> |
| 24 | #include <linux/list.h> |
| 25 | #include <linux/netdevice.h> |
| 26 | #include <linux/in6.h> |
| 27 | #include <linux/ipv6.h> |
| 28 | #include <linux/icmpv6.h> |
| 29 | #include <linux/random.h> |
| 30 | #include <linux/jhash.h> |
| 31 | |
| 32 | #include <net/sock.h> |
| 33 | #include <net/snmp.h> |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 34 | #include <net/inet_frag.h> |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 35 | |
| 36 | #include <net/ipv6.h> |
| 37 | #include <net/protocol.h> |
| 38 | #include <net/transp_v6.h> |
| 39 | #include <net/rawv6.h> |
| 40 | #include <net/ndisc.h> |
| 41 | #include <net/addrconf.h> |
| 42 | #include <linux/sysctl.h> |
| 43 | #include <linux/netfilter.h> |
| 44 | #include <linux/netfilter_ipv6.h> |
| 45 | #include <linux/kernel.h> |
| 46 | #include <linux/module.h> |
| 47 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 48 | #define NF_CT_FRAG6_HIGH_THRESH 262144 /* == 256*1024 */ |
| 49 | #define NF_CT_FRAG6_LOW_THRESH 196608 /* == 192*1024 */ |
| 50 | #define NF_CT_FRAG6_TIMEOUT IPV6_FRAG_TIMEOUT |
| 51 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 52 | struct nf_ct_frag6_skb_cb |
| 53 | { |
| 54 | struct inet6_skb_parm h; |
| 55 | int offset; |
| 56 | struct sk_buff *orig; |
| 57 | }; |
| 58 | |
| 59 | #define NFCT_FRAG6_CB(skb) ((struct nf_ct_frag6_skb_cb*)((skb)->cb)) |
| 60 | |
| 61 | struct nf_ct_frag6_queue |
| 62 | { |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 63 | struct inet_frag_queue q; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 64 | |
Patrick McHardy | bff9a89 | 2006-12-02 22:05:08 -0800 | [diff] [blame] | 65 | __be32 id; /* fragment id */ |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 66 | struct in6_addr saddr; |
| 67 | struct in6_addr daddr; |
| 68 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 69 | unsigned int csum; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 70 | __u16 nhoffset; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 71 | }; |
| 72 | |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 73 | static struct inet_frags nf_frags; |
Pavel Emelyanov | ac18e75 | 2008-01-22 06:02:14 -0800 | [diff] [blame] | 74 | static struct netns_frags nf_init_frags; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 75 | |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 76 | #ifdef CONFIG_SYSCTL |
| 77 | struct ctl_table nf_ct_ipv6_sysctl_table[] = { |
| 78 | { |
| 79 | .procname = "nf_conntrack_frag6_timeout", |
Pavel Emelyanov | b2fd532 | 2008-01-22 06:09:37 -0800 | [diff] [blame] | 80 | .data = &nf_init_frags.timeout, |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 81 | .maxlen = sizeof(unsigned int), |
| 82 | .mode = 0644, |
| 83 | .proc_handler = &proc_dointvec_jiffies, |
| 84 | }, |
| 85 | { |
| 86 | .ctl_name = NET_NF_CONNTRACK_FRAG6_LOW_THRESH, |
| 87 | .procname = "nf_conntrack_frag6_low_thresh", |
Pavel Emelyanov | e31e0bdc7 | 2008-01-22 06:10:13 -0800 | [diff] [blame] | 88 | .data = &nf_init_frags.low_thresh, |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 89 | .maxlen = sizeof(unsigned int), |
| 90 | .mode = 0644, |
| 91 | .proc_handler = &proc_dointvec, |
| 92 | }, |
| 93 | { |
| 94 | .ctl_name = NET_NF_CONNTRACK_FRAG6_HIGH_THRESH, |
| 95 | .procname = "nf_conntrack_frag6_high_thresh", |
Pavel Emelyanov | e31e0bdc7 | 2008-01-22 06:10:13 -0800 | [diff] [blame] | 96 | .data = &nf_init_frags.high_thresh, |
Pavel Emelyanov | 8d8354d | 2008-01-22 05:58:31 -0800 | [diff] [blame] | 97 | .maxlen = sizeof(unsigned int), |
| 98 | .mode = 0644, |
| 99 | .proc_handler = &proc_dointvec, |
| 100 | }, |
| 101 | { .ctl_name = 0 } |
| 102 | }; |
| 103 | #endif |
| 104 | |
Patrick McHardy | bff9a89 | 2006-12-02 22:05:08 -0800 | [diff] [blame] | 105 | static unsigned int ip6qhashfn(__be32 id, struct in6_addr *saddr, |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 106 | struct in6_addr *daddr) |
| 107 | { |
| 108 | u32 a, b, c; |
| 109 | |
Patrick McHardy | bff9a89 | 2006-12-02 22:05:08 -0800 | [diff] [blame] | 110 | a = (__force u32)saddr->s6_addr32[0]; |
| 111 | b = (__force u32)saddr->s6_addr32[1]; |
| 112 | c = (__force u32)saddr->s6_addr32[2]; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 113 | |
| 114 | a += JHASH_GOLDEN_RATIO; |
| 115 | b += JHASH_GOLDEN_RATIO; |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 116 | c += nf_frags.rnd; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 117 | __jhash_mix(a, b, c); |
| 118 | |
Patrick McHardy | bff9a89 | 2006-12-02 22:05:08 -0800 | [diff] [blame] | 119 | a += (__force u32)saddr->s6_addr32[3]; |
| 120 | b += (__force u32)daddr->s6_addr32[0]; |
| 121 | c += (__force u32)daddr->s6_addr32[1]; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 122 | __jhash_mix(a, b, c); |
| 123 | |
Patrick McHardy | bff9a89 | 2006-12-02 22:05:08 -0800 | [diff] [blame] | 124 | a += (__force u32)daddr->s6_addr32[2]; |
| 125 | b += (__force u32)daddr->s6_addr32[3]; |
| 126 | c += (__force u32)id; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 127 | __jhash_mix(a, b, c); |
| 128 | |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 129 | return c & (INETFRAGS_HASHSZ - 1); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 130 | } |
| 131 | |
Pavel Emelyanov | 321a3a9 | 2007-10-15 02:38:08 -0700 | [diff] [blame] | 132 | static unsigned int nf_hashfn(struct inet_frag_queue *q) |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 133 | { |
Pavel Emelyanov | 321a3a9 | 2007-10-15 02:38:08 -0700 | [diff] [blame] | 134 | struct nf_ct_frag6_queue *nq; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 135 | |
Pavel Emelyanov | 321a3a9 | 2007-10-15 02:38:08 -0700 | [diff] [blame] | 136 | nq = container_of(q, struct nf_ct_frag6_queue, q); |
| 137 | return ip6qhashfn(nq->id, &nq->saddr, &nq->daddr); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 138 | } |
| 139 | |
Pavel Emelyanov | 1e4b828 | 2007-10-15 02:39:14 -0700 | [diff] [blame] | 140 | static void nf_skb_free(struct sk_buff *skb) |
| 141 | { |
| 142 | if (NFCT_FRAG6_CB(skb)->orig) |
| 143 | kfree_skb(NFCT_FRAG6_CB(skb)->orig); |
| 144 | } |
| 145 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 146 | /* Memory Tracking Functions. */ |
Yasuyuki Kozakai | 1ba430b | 2005-11-14 15:28:18 -0800 | [diff] [blame] | 147 | static inline void frag_kfree_skb(struct sk_buff *skb, unsigned int *work) |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 148 | { |
Yasuyuki Kozakai | 1ba430b | 2005-11-14 15:28:18 -0800 | [diff] [blame] | 149 | if (work) |
| 150 | *work -= skb->truesize; |
Pavel Emelyanov | 6ddc082 | 2008-01-22 06:07:25 -0800 | [diff] [blame] | 151 | atomic_sub(skb->truesize, &nf_init_frags.mem); |
Pavel Emelyanov | 1e4b828 | 2007-10-15 02:39:14 -0700 | [diff] [blame] | 152 | nf_skb_free(skb); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 153 | kfree_skb(skb); |
| 154 | } |
| 155 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 156 | /* Destruction primitives. */ |
| 157 | |
Pavel Emelyanov | 4b6cb5d | 2007-10-15 02:41:09 -0700 | [diff] [blame] | 158 | static __inline__ void fq_put(struct nf_ct_frag6_queue *fq) |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 159 | { |
Pavel Emelyanov | 762cc40 | 2007-10-15 02:41:56 -0700 | [diff] [blame] | 160 | inet_frag_put(&fq->q, &nf_frags); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 161 | } |
| 162 | |
| 163 | /* Kill fq entry. It is not destroyed immediately, |
| 164 | * because caller (and someone more) holds reference count. |
| 165 | */ |
| 166 | static __inline__ void fq_kill(struct nf_ct_frag6_queue *fq) |
| 167 | { |
Pavel Emelyanov | 277e650 | 2007-10-15 02:37:18 -0700 | [diff] [blame] | 168 | inet_frag_kill(&fq->q, &nf_frags); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 169 | } |
| 170 | |
| 171 | static void nf_ct_frag6_evictor(void) |
| 172 | { |
Pavel Emelyanov | 6ddc082 | 2008-01-22 06:07:25 -0800 | [diff] [blame] | 173 | inet_frag_evictor(&nf_init_frags, &nf_frags); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 174 | } |
| 175 | |
| 176 | static void nf_ct_frag6_expire(unsigned long data) |
| 177 | { |
Pavel Emelyanov | e521db9 | 2007-10-17 19:45:23 -0700 | [diff] [blame] | 178 | struct nf_ct_frag6_queue *fq; |
| 179 | |
| 180 | fq = container_of((struct inet_frag_queue *)data, |
| 181 | struct nf_ct_frag6_queue, q); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 182 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 183 | spin_lock(&fq->q.lock); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 184 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 185 | if (fq->q.last_in & COMPLETE) |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 186 | goto out; |
| 187 | |
| 188 | fq_kill(fq); |
| 189 | |
| 190 | out: |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 191 | spin_unlock(&fq->q.lock); |
Pavel Emelyanov | 4b6cb5d | 2007-10-15 02:41:09 -0700 | [diff] [blame] | 192 | fq_put(fq); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 193 | } |
| 194 | |
| 195 | /* Creation primitives. */ |
| 196 | |
Pavel Emelyanov | abd6523 | 2007-10-17 19:47:21 -0700 | [diff] [blame] | 197 | static __inline__ struct nf_ct_frag6_queue * |
| 198 | fq_find(__be32 id, struct in6_addr *src, struct in6_addr *dst) |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 199 | { |
Pavel Emelyanov | 2588fe1 | 2007-10-17 19:44:34 -0700 | [diff] [blame] | 200 | struct inet_frag_queue *q; |
Pavel Emelyanov | c6fda28 | 2007-10-17 19:46:47 -0700 | [diff] [blame] | 201 | struct ip6_create_arg arg; |
Pavel Emelyanov | abd6523 | 2007-10-17 19:47:21 -0700 | [diff] [blame] | 202 | unsigned int hash; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 203 | |
Pavel Emelyanov | c6fda28 | 2007-10-17 19:46:47 -0700 | [diff] [blame] | 204 | arg.id = id; |
| 205 | arg.src = src; |
| 206 | arg.dst = dst; |
Pavel Emelyanov | abd6523 | 2007-10-17 19:47:21 -0700 | [diff] [blame] | 207 | hash = ip6qhashfn(id, src, dst); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 208 | |
Pavel Emelyanov | ac18e75 | 2008-01-22 06:02:14 -0800 | [diff] [blame] | 209 | q = inet_frag_find(&nf_init_frags, &nf_frags, &arg, hash); |
Pavel Emelyanov | c6fda28 | 2007-10-17 19:46:47 -0700 | [diff] [blame] | 210 | if (q == NULL) |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 211 | goto oom; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 212 | |
Pavel Emelyanov | c6fda28 | 2007-10-17 19:46:47 -0700 | [diff] [blame] | 213 | return container_of(q, struct nf_ct_frag6_queue, q); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 214 | |
| 215 | oom: |
Pavel Emelyanov | c6fda28 | 2007-10-17 19:46:47 -0700 | [diff] [blame] | 216 | pr_debug("Can't alloc new queue\n"); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 217 | return NULL; |
| 218 | } |
| 219 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 220 | |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 221 | static int nf_ct_frag6_queue(struct nf_ct_frag6_queue *fq, struct sk_buff *skb, |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 222 | struct frag_hdr *fhdr, int nhoff) |
| 223 | { |
| 224 | struct sk_buff *prev, *next; |
| 225 | int offset, end; |
| 226 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 227 | if (fq->q.last_in & COMPLETE) { |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 228 | pr_debug("Allready completed\n"); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 229 | goto err; |
| 230 | } |
| 231 | |
| 232 | offset = ntohs(fhdr->frag_off) & ~0x7; |
Arnaldo Carvalho de Melo | 0660e03 | 2007-04-25 17:54:47 -0700 | [diff] [blame] | 233 | end = offset + (ntohs(ipv6_hdr(skb)->payload_len) - |
| 234 | ((u8 *)(fhdr + 1) - (u8 *)(ipv6_hdr(skb) + 1))); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 235 | |
| 236 | if ((unsigned int)end > IPV6_MAXPLEN) { |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 237 | pr_debug("offset is too large.\n"); |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 238 | return -1; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 239 | } |
| 240 | |
Arnaldo Carvalho de Melo | d56f90a | 2007-04-10 20:50:43 -0700 | [diff] [blame] | 241 | if (skb->ip_summed == CHECKSUM_COMPLETE) { |
| 242 | const unsigned char *nh = skb_network_header(skb); |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 243 | skb->csum = csum_sub(skb->csum, |
Arnaldo Carvalho de Melo | d56f90a | 2007-04-10 20:50:43 -0700 | [diff] [blame] | 244 | csum_partial(nh, (u8 *)(fhdr + 1) - nh, |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 245 | 0)); |
Arnaldo Carvalho de Melo | d56f90a | 2007-04-10 20:50:43 -0700 | [diff] [blame] | 246 | } |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 247 | |
| 248 | /* Is this the final fragment? */ |
| 249 | if (!(fhdr->frag_off & htons(IP6_MF))) { |
| 250 | /* If we already have some bits beyond end |
| 251 | * or have different end, the segment is corrupted. |
| 252 | */ |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 253 | if (end < fq->q.len || |
| 254 | ((fq->q.last_in & LAST_IN) && end != fq->q.len)) { |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 255 | pr_debug("already received last fragment\n"); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 256 | goto err; |
| 257 | } |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 258 | fq->q.last_in |= LAST_IN; |
| 259 | fq->q.len = end; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 260 | } else { |
| 261 | /* Check if the fragment is rounded to 8 bytes. |
| 262 | * Required by the RFC. |
| 263 | */ |
| 264 | if (end & 0x7) { |
| 265 | /* RFC2460 says always send parameter problem in |
| 266 | * this case. -DaveM |
| 267 | */ |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 268 | pr_debug("end of fragment not rounded to 8 bytes.\n"); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 269 | return -1; |
| 270 | } |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 271 | if (end > fq->q.len) { |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 272 | /* Some bits beyond end -> corruption. */ |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 273 | if (fq->q.last_in & LAST_IN) { |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 274 | pr_debug("last packet already reached.\n"); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 275 | goto err; |
| 276 | } |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 277 | fq->q.len = end; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 278 | } |
| 279 | } |
| 280 | |
| 281 | if (end == offset) |
| 282 | goto err; |
| 283 | |
| 284 | /* Point into the IP datagram 'data' part. */ |
| 285 | if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data)) { |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 286 | pr_debug("queue: message is too short.\n"); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 287 | goto err; |
| 288 | } |
Herbert Xu | b38dfee | 2006-06-09 16:13:01 -0700 | [diff] [blame] | 289 | if (pskb_trim_rcsum(skb, end - offset)) { |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 290 | pr_debug("Can't trim\n"); |
Herbert Xu | b38dfee | 2006-06-09 16:13:01 -0700 | [diff] [blame] | 291 | goto err; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 292 | } |
| 293 | |
| 294 | /* Find out which fragments are in front and at the back of us |
| 295 | * in the chain of fragments so far. We must know where to put |
| 296 | * this fragment, right? |
| 297 | */ |
| 298 | prev = NULL; |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 299 | for (next = fq->q.fragments; next != NULL; next = next->next) { |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 300 | if (NFCT_FRAG6_CB(next)->offset >= offset) |
| 301 | break; /* bingo! */ |
| 302 | prev = next; |
| 303 | } |
| 304 | |
| 305 | /* We found where to put this one. Check for overlap with |
| 306 | * preceding fragment, and, if needed, align things so that |
| 307 | * any overlaps are eliminated. |
| 308 | */ |
| 309 | if (prev) { |
| 310 | int i = (NFCT_FRAG6_CB(prev)->offset + prev->len) - offset; |
| 311 | |
| 312 | if (i > 0) { |
| 313 | offset += i; |
| 314 | if (end <= offset) { |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 315 | pr_debug("overlap\n"); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 316 | goto err; |
| 317 | } |
| 318 | if (!pskb_pull(skb, i)) { |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 319 | pr_debug("Can't pull\n"); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 320 | goto err; |
| 321 | } |
| 322 | if (skb->ip_summed != CHECKSUM_UNNECESSARY) |
| 323 | skb->ip_summed = CHECKSUM_NONE; |
| 324 | } |
| 325 | } |
| 326 | |
| 327 | /* Look for overlap with succeeding segments. |
| 328 | * If we can merge fragments, do it. |
| 329 | */ |
| 330 | while (next && NFCT_FRAG6_CB(next)->offset < end) { |
| 331 | /* overlap is 'i' bytes */ |
| 332 | int i = end - NFCT_FRAG6_CB(next)->offset; |
| 333 | |
| 334 | if (i < next->len) { |
| 335 | /* Eat head of the next overlapped fragment |
| 336 | * and leave the loop. The next ones cannot overlap. |
| 337 | */ |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 338 | pr_debug("Eat head of the overlapped parts.: %d", i); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 339 | if (!pskb_pull(next, i)) |
| 340 | goto err; |
| 341 | |
| 342 | /* next fragment */ |
| 343 | NFCT_FRAG6_CB(next)->offset += i; |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 344 | fq->q.meat -= i; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 345 | if (next->ip_summed != CHECKSUM_UNNECESSARY) |
| 346 | next->ip_summed = CHECKSUM_NONE; |
| 347 | break; |
| 348 | } else { |
| 349 | struct sk_buff *free_it = next; |
| 350 | |
| 351 | /* Old fragmnet is completely overridden with |
| 352 | * new one drop it. |
| 353 | */ |
| 354 | next = next->next; |
| 355 | |
| 356 | if (prev) |
| 357 | prev->next = next; |
| 358 | else |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 359 | fq->q.fragments = next; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 360 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 361 | fq->q.meat -= free_it->len; |
Yasuyuki Kozakai | 1ba430b | 2005-11-14 15:28:18 -0800 | [diff] [blame] | 362 | frag_kfree_skb(free_it, NULL); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 363 | } |
| 364 | } |
| 365 | |
| 366 | NFCT_FRAG6_CB(skb)->offset = offset; |
| 367 | |
| 368 | /* Insert this fragment in the chain of fragments. */ |
| 369 | skb->next = next; |
| 370 | if (prev) |
| 371 | prev->next = skb; |
| 372 | else |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 373 | fq->q.fragments = skb; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 374 | |
| 375 | skb->dev = NULL; |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 376 | fq->q.stamp = skb->tstamp; |
| 377 | fq->q.meat += skb->len; |
Pavel Emelyanov | 6ddc082 | 2008-01-22 06:07:25 -0800 | [diff] [blame] | 378 | atomic_add(skb->truesize, &nf_init_frags.mem); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 379 | |
| 380 | /* The first fragment. |
| 381 | * nhoffset is obtained from the first fragment, of course. |
| 382 | */ |
| 383 | if (offset == 0) { |
| 384 | fq->nhoffset = nhoff; |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 385 | fq->q.last_in |= FIRST_IN; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 386 | } |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 387 | write_lock(&nf_frags.lock); |
| 388 | list_move_tail(&fq->q.lru_list, &nf_frags.lru_list); |
| 389 | write_unlock(&nf_frags.lock); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 390 | return 0; |
| 391 | |
| 392 | err: |
| 393 | return -1; |
| 394 | } |
| 395 | |
| 396 | /* |
| 397 | * Check if this packet is complete. |
| 398 | * Returns NULL on failure by any reason, and pointer |
| 399 | * to current nexthdr field in reassembled frame. |
| 400 | * |
| 401 | * It is called with locked fq, and caller must check that |
| 402 | * queue is eligible for reassembly i.e. it is not COMPLETE, |
| 403 | * the last and the first frames arrived and all the bits are here. |
| 404 | */ |
| 405 | static struct sk_buff * |
| 406 | nf_ct_frag6_reasm(struct nf_ct_frag6_queue *fq, struct net_device *dev) |
| 407 | { |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 408 | struct sk_buff *fp, *op, *head = fq->q.fragments; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 409 | int payload_len; |
| 410 | |
| 411 | fq_kill(fq); |
| 412 | |
| 413 | BUG_TRAP(head != NULL); |
| 414 | BUG_TRAP(NFCT_FRAG6_CB(head)->offset == 0); |
| 415 | |
| 416 | /* Unfragmented part is taken from the first segment. */ |
Arnaldo Carvalho de Melo | d56f90a | 2007-04-10 20:50:43 -0700 | [diff] [blame] | 417 | payload_len = ((head->data - skb_network_header(head)) - |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 418 | sizeof(struct ipv6hdr) + fq->q.len - |
Arnaldo Carvalho de Melo | d56f90a | 2007-04-10 20:50:43 -0700 | [diff] [blame] | 419 | sizeof(struct frag_hdr)); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 420 | if (payload_len > IPV6_MAXPLEN) { |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 421 | pr_debug("payload len is too large.\n"); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 422 | goto out_oversize; |
| 423 | } |
| 424 | |
| 425 | /* Head of list must not be cloned. */ |
| 426 | if (skb_cloned(head) && pskb_expand_head(head, 0, 0, GFP_ATOMIC)) { |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 427 | pr_debug("skb is cloned but can't expand head"); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 428 | goto out_oom; |
| 429 | } |
| 430 | |
| 431 | /* If the first fragment is fragmented itself, we split |
| 432 | * it to two chunks: the first with data and paged part |
| 433 | * and the second, holding only fragments. */ |
| 434 | if (skb_shinfo(head)->frag_list) { |
| 435 | struct sk_buff *clone; |
| 436 | int i, plen = 0; |
| 437 | |
| 438 | if ((clone = alloc_skb(0, GFP_ATOMIC)) == NULL) { |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 439 | pr_debug("Can't alloc skb\n"); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 440 | goto out_oom; |
| 441 | } |
| 442 | clone->next = head->next; |
| 443 | head->next = clone; |
| 444 | skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list; |
| 445 | skb_shinfo(head)->frag_list = NULL; |
| 446 | for (i=0; i<skb_shinfo(head)->nr_frags; i++) |
| 447 | plen += skb_shinfo(head)->frags[i].size; |
| 448 | clone->len = clone->data_len = head->data_len - plen; |
| 449 | head->data_len -= clone->len; |
| 450 | head->len -= clone->len; |
| 451 | clone->csum = 0; |
| 452 | clone->ip_summed = head->ip_summed; |
| 453 | |
| 454 | NFCT_FRAG6_CB(clone)->orig = NULL; |
Pavel Emelyanov | 6ddc082 | 2008-01-22 06:07:25 -0800 | [diff] [blame] | 455 | atomic_add(clone->truesize, &nf_init_frags.mem); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 456 | } |
| 457 | |
| 458 | /* We have to remove fragment header from datagram and to relocate |
| 459 | * header in order to calculate ICV correctly. */ |
Arnaldo Carvalho de Melo | bff9b61 | 2007-03-16 17:19:57 -0300 | [diff] [blame] | 460 | skb_network_header(head)[fq->nhoffset] = skb_transport_header(head)[0]; |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 461 | memmove(head->head + sizeof(struct frag_hdr), head->head, |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 462 | (head->data - head->head) - sizeof(struct frag_hdr)); |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 463 | head->mac_header += sizeof(struct frag_hdr); |
| 464 | head->network_header += sizeof(struct frag_hdr); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 465 | |
| 466 | skb_shinfo(head)->frag_list = head->next; |
Arnaldo Carvalho de Melo | badff6d | 2007-03-13 13:06:52 -0300 | [diff] [blame] | 467 | skb_reset_transport_header(head); |
Arnaldo Carvalho de Melo | d56f90a | 2007-04-10 20:50:43 -0700 | [diff] [blame] | 468 | skb_push(head, head->data - skb_network_header(head)); |
Pavel Emelyanov | 6ddc082 | 2008-01-22 06:07:25 -0800 | [diff] [blame] | 469 | atomic_sub(head->truesize, &nf_init_frags.mem); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 470 | |
| 471 | for (fp=head->next; fp; fp = fp->next) { |
| 472 | head->data_len += fp->len; |
| 473 | head->len += fp->len; |
| 474 | if (head->ip_summed != fp->ip_summed) |
| 475 | head->ip_summed = CHECKSUM_NONE; |
Patrick McHardy | 84fa793 | 2006-08-29 16:44:56 -0700 | [diff] [blame] | 476 | else if (head->ip_summed == CHECKSUM_COMPLETE) |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 477 | head->csum = csum_add(head->csum, fp->csum); |
| 478 | head->truesize += fp->truesize; |
Pavel Emelyanov | 6ddc082 | 2008-01-22 06:07:25 -0800 | [diff] [blame] | 479 | atomic_sub(fp->truesize, &nf_init_frags.mem); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 480 | } |
| 481 | |
| 482 | head->next = NULL; |
| 483 | head->dev = dev; |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 484 | head->tstamp = fq->q.stamp; |
Arnaldo Carvalho de Melo | 0660e03 | 2007-04-25 17:54:47 -0700 | [diff] [blame] | 485 | ipv6_hdr(head)->payload_len = htons(payload_len); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 486 | |
| 487 | /* Yes, and fold redundant checksum back. 8) */ |
Patrick McHardy | 84fa793 | 2006-08-29 16:44:56 -0700 | [diff] [blame] | 488 | if (head->ip_summed == CHECKSUM_COMPLETE) |
Arnaldo Carvalho de Melo | d56f90a | 2007-04-10 20:50:43 -0700 | [diff] [blame] | 489 | head->csum = csum_partial(skb_network_header(head), |
Arnaldo Carvalho de Melo | cfe1fc7 | 2007-03-16 17:26:39 -0300 | [diff] [blame] | 490 | skb_network_header_len(head), |
Arnaldo Carvalho de Melo | d56f90a | 2007-04-10 20:50:43 -0700 | [diff] [blame] | 491 | head->csum); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 492 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 493 | fq->q.fragments = NULL; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 494 | |
| 495 | /* all original skbs are linked into the NFCT_FRAG6_CB(head).orig */ |
| 496 | fp = skb_shinfo(head)->frag_list; |
| 497 | if (NFCT_FRAG6_CB(fp)->orig == NULL) |
| 498 | /* at above code, head skb is divided into two skbs. */ |
| 499 | fp = fp->next; |
| 500 | |
| 501 | op = NFCT_FRAG6_CB(head)->orig; |
| 502 | for (; fp; fp = fp->next) { |
| 503 | struct sk_buff *orig = NFCT_FRAG6_CB(fp)->orig; |
| 504 | |
| 505 | op->next = orig; |
| 506 | op = orig; |
| 507 | NFCT_FRAG6_CB(fp)->orig = NULL; |
| 508 | } |
| 509 | |
| 510 | return head; |
| 511 | |
| 512 | out_oversize: |
| 513 | if (net_ratelimit()) |
| 514 | printk(KERN_DEBUG "nf_ct_frag6_reasm: payload len = %d\n", payload_len); |
| 515 | goto out_fail; |
| 516 | out_oom: |
| 517 | if (net_ratelimit()) |
| 518 | printk(KERN_DEBUG "nf_ct_frag6_reasm: no memory for reassembly\n"); |
| 519 | out_fail: |
| 520 | return NULL; |
| 521 | } |
| 522 | |
| 523 | /* |
| 524 | * find the header just before Fragment Header. |
| 525 | * |
| 526 | * if success return 0 and set ... |
| 527 | * (*prevhdrp): the value of "Next Header Field" in the header |
| 528 | * just before Fragment Header. |
| 529 | * (*prevhoff): the offset of "Next Header Field" in the header |
| 530 | * just before Fragment Header. |
| 531 | * (*fhoff) : the offset of Fragment Header. |
| 532 | * |
| 533 | * Based on ipv6_skip_hdr() in net/ipv6/exthdr.c |
| 534 | * |
| 535 | */ |
| 536 | static int |
| 537 | find_prev_fhdr(struct sk_buff *skb, u8 *prevhdrp, int *prevhoff, int *fhoff) |
| 538 | { |
Arnaldo Carvalho de Melo | 0660e03 | 2007-04-25 17:54:47 -0700 | [diff] [blame] | 539 | u8 nexthdr = ipv6_hdr(skb)->nexthdr; |
Arnaldo Carvalho de Melo | 6b88dd9 | 2007-03-19 22:29:03 -0300 | [diff] [blame] | 540 | const int netoff = skb_network_offset(skb); |
| 541 | u8 prev_nhoff = netoff + offsetof(struct ipv6hdr, nexthdr); |
| 542 | int start = netoff + sizeof(struct ipv6hdr); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 543 | int len = skb->len - start; |
| 544 | u8 prevhdr = NEXTHDR_IPV6; |
| 545 | |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 546 | while (nexthdr != NEXTHDR_FRAGMENT) { |
| 547 | struct ipv6_opt_hdr hdr; |
| 548 | int hdrlen; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 549 | |
| 550 | if (!ipv6_ext_hdr(nexthdr)) { |
| 551 | return -1; |
| 552 | } |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 553 | if (len < (int)sizeof(struct ipv6_opt_hdr)) { |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 554 | pr_debug("too short\n"); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 555 | return -1; |
| 556 | } |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 557 | if (nexthdr == NEXTHDR_NONE) { |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 558 | pr_debug("next header is none\n"); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 559 | return -1; |
| 560 | } |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 561 | if (skb_copy_bits(skb, start, &hdr, sizeof(hdr))) |
| 562 | BUG(); |
| 563 | if (nexthdr == NEXTHDR_AUTH) |
| 564 | hdrlen = (hdr.hdrlen+2)<<2; |
| 565 | else |
| 566 | hdrlen = ipv6_optlen(&hdr); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 567 | |
| 568 | prevhdr = nexthdr; |
| 569 | prev_nhoff = start; |
| 570 | |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 571 | nexthdr = hdr.nexthdr; |
| 572 | len -= hdrlen; |
| 573 | start += hdrlen; |
| 574 | } |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 575 | |
| 576 | if (len < 0) |
| 577 | return -1; |
| 578 | |
| 579 | *prevhdrp = prevhdr; |
| 580 | *prevhoff = prev_nhoff; |
| 581 | *fhoff = start; |
| 582 | |
| 583 | return 0; |
| 584 | } |
| 585 | |
| 586 | struct sk_buff *nf_ct_frag6_gather(struct sk_buff *skb) |
| 587 | { |
YOSHIFUJI Hideaki | 1ab1457 | 2007-02-09 23:24:49 +0900 | [diff] [blame] | 588 | struct sk_buff *clone; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 589 | struct net_device *dev = skb->dev; |
| 590 | struct frag_hdr *fhdr; |
| 591 | struct nf_ct_frag6_queue *fq; |
| 592 | struct ipv6hdr *hdr; |
| 593 | int fhoff, nhoff; |
| 594 | u8 prevhdr; |
| 595 | struct sk_buff *ret_skb = NULL; |
| 596 | |
| 597 | /* Jumbo payload inhibits frag. header */ |
Arnaldo Carvalho de Melo | 0660e03 | 2007-04-25 17:54:47 -0700 | [diff] [blame] | 598 | if (ipv6_hdr(skb)->payload_len == 0) { |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 599 | pr_debug("payload len = 0\n"); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 600 | return skb; |
| 601 | } |
| 602 | |
| 603 | if (find_prev_fhdr(skb, &prevhdr, &nhoff, &fhoff) < 0) |
| 604 | return skb; |
| 605 | |
| 606 | clone = skb_clone(skb, GFP_ATOMIC); |
| 607 | if (clone == NULL) { |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 608 | pr_debug("Can't clone skb\n"); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 609 | return skb; |
| 610 | } |
| 611 | |
| 612 | NFCT_FRAG6_CB(clone)->orig = skb; |
| 613 | |
| 614 | if (!pskb_may_pull(clone, fhoff + sizeof(*fhdr))) { |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 615 | pr_debug("message is too short.\n"); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 616 | goto ret_orig; |
| 617 | } |
| 618 | |
Arnaldo Carvalho de Melo | 967b05f | 2007-03-13 13:51:52 -0300 | [diff] [blame] | 619 | skb_set_transport_header(clone, fhoff); |
Arnaldo Carvalho de Melo | 0660e03 | 2007-04-25 17:54:47 -0700 | [diff] [blame] | 620 | hdr = ipv6_hdr(clone); |
Arnaldo Carvalho de Melo | bff9b61 | 2007-03-16 17:19:57 -0300 | [diff] [blame] | 621 | fhdr = (struct frag_hdr *)skb_transport_header(clone); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 622 | |
| 623 | if (!(fhdr->frag_off & htons(0xFFF9))) { |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 624 | pr_debug("Invalid fragment offset\n"); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 625 | /* It is not a fragmented frame */ |
| 626 | goto ret_orig; |
| 627 | } |
| 628 | |
Pavel Emelyanov | e31e0bdc7 | 2008-01-22 06:10:13 -0800 | [diff] [blame] | 629 | if (atomic_read(&nf_init_frags.mem) > nf_init_frags.high_thresh) |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 630 | nf_ct_frag6_evictor(); |
| 631 | |
| 632 | fq = fq_find(fhdr->identification, &hdr->saddr, &hdr->daddr); |
| 633 | if (fq == NULL) { |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 634 | pr_debug("Can't find and can't create new queue\n"); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 635 | goto ret_orig; |
| 636 | } |
| 637 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 638 | spin_lock(&fq->q.lock); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 639 | |
| 640 | if (nf_ct_frag6_queue(fq, clone, fhdr, nhoff) < 0) { |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 641 | spin_unlock(&fq->q.lock); |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 642 | pr_debug("Can't insert skb to queue\n"); |
Pavel Emelyanov | 4b6cb5d | 2007-10-15 02:41:09 -0700 | [diff] [blame] | 643 | fq_put(fq); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 644 | goto ret_orig; |
| 645 | } |
| 646 | |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 647 | if (fq->q.last_in == (FIRST_IN|LAST_IN) && fq->q.meat == fq->q.len) { |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 648 | ret_skb = nf_ct_frag6_reasm(fq, dev); |
| 649 | if (ret_skb == NULL) |
Patrick McHardy | 0d53778 | 2007-07-07 22:39:38 -0700 | [diff] [blame] | 650 | pr_debug("Can't reassemble fragmented packets\n"); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 651 | } |
Pavel Emelyanov | 5ab11c9 | 2007-10-15 02:24:19 -0700 | [diff] [blame] | 652 | spin_unlock(&fq->q.lock); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 653 | |
Pavel Emelyanov | 4b6cb5d | 2007-10-15 02:41:09 -0700 | [diff] [blame] | 654 | fq_put(fq); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 655 | return ret_skb; |
| 656 | |
| 657 | ret_orig: |
| 658 | kfree_skb(clone); |
| 659 | return skb; |
| 660 | } |
| 661 | |
| 662 | void nf_ct_frag6_output(unsigned int hooknum, struct sk_buff *skb, |
| 663 | struct net_device *in, struct net_device *out, |
| 664 | int (*okfn)(struct sk_buff *)) |
| 665 | { |
| 666 | struct sk_buff *s, *s2; |
| 667 | |
| 668 | for (s = NFCT_FRAG6_CB(skb)->orig; s;) { |
| 669 | nf_conntrack_put_reasm(s->nfct_reasm); |
| 670 | nf_conntrack_get_reasm(skb); |
| 671 | s->nfct_reasm = skb; |
| 672 | |
| 673 | s2 = s->next; |
Patrick McHardy | f9f02cc | 2007-01-09 14:32:41 -0800 | [diff] [blame] | 674 | s->next = NULL; |
| 675 | |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 676 | NF_HOOK_THRESH(PF_INET6, hooknum, s, in, out, okfn, |
| 677 | NF_IP6_PRI_CONNTRACK_DEFRAG + 1); |
| 678 | s = s2; |
| 679 | } |
| 680 | nf_conntrack_put_reasm(skb); |
| 681 | } |
| 682 | |
| 683 | int nf_ct_frag6_kfree_frags(struct sk_buff *skb) |
| 684 | { |
| 685 | struct sk_buff *s, *s2; |
| 686 | |
| 687 | for (s = NFCT_FRAG6_CB(skb)->orig; s; s = s2) { |
| 688 | |
| 689 | s2 = s->next; |
| 690 | kfree_skb(s); |
| 691 | } |
| 692 | |
| 693 | kfree_skb(skb); |
| 694 | |
| 695 | return 0; |
| 696 | } |
| 697 | |
| 698 | int nf_ct_frag6_init(void) |
| 699 | { |
Pavel Emelyanov | 321a3a9 | 2007-10-15 02:38:08 -0700 | [diff] [blame] | 700 | nf_frags.hashfn = nf_hashfn; |
Pavel Emelyanov | c6fda28 | 2007-10-17 19:46:47 -0700 | [diff] [blame] | 701 | nf_frags.constructor = ip6_frag_init; |
Pavel Emelyanov | c954770 | 2007-10-17 19:48:26 -0700 | [diff] [blame] | 702 | nf_frags.destructor = NULL; |
Pavel Emelyanov | 1e4b828 | 2007-10-15 02:39:14 -0700 | [diff] [blame] | 703 | nf_frags.skb_free = nf_skb_free; |
| 704 | nf_frags.qsize = sizeof(struct nf_ct_frag6_queue); |
Pavel Emelyanov | abd6523 | 2007-10-17 19:47:21 -0700 | [diff] [blame] | 705 | nf_frags.match = ip6_frag_match; |
Pavel Emelyanov | e521db9 | 2007-10-17 19:45:23 -0700 | [diff] [blame] | 706 | nf_frags.frag_expire = nf_ct_frag6_expire; |
Pavel Emelyanov | 3b4bc4a | 2008-01-22 06:11:04 -0800 | [diff] [blame^] | 707 | nf_frags.secret_interval = 10 * 60 * HZ; |
Pavel Emelyanov | b2fd532 | 2008-01-22 06:09:37 -0800 | [diff] [blame] | 708 | nf_init_frags.timeout = IPV6_FRAG_TIMEOUT; |
Pavel Emelyanov | e31e0bdc7 | 2008-01-22 06:10:13 -0800 | [diff] [blame] | 709 | nf_init_frags.high_thresh = 256 * 1024; |
| 710 | nf_init_frags.low_thresh = 192 * 1024; |
Pavel Emelyanov | e5a2bb8 | 2008-01-22 06:06:23 -0800 | [diff] [blame] | 711 | inet_frags_init_net(&nf_init_frags); |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 712 | inet_frags_init(&nf_frags); |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 713 | |
| 714 | return 0; |
| 715 | } |
| 716 | |
| 717 | void nf_ct_frag6_cleanup(void) |
| 718 | { |
Pavel Emelyanov | 7eb9515 | 2007-10-15 02:31:52 -0700 | [diff] [blame] | 719 | inet_frags_fini(&nf_frags); |
| 720 | |
Pavel Emelyanov | e31e0bdc7 | 2008-01-22 06:10:13 -0800 | [diff] [blame] | 721 | nf_init_frags.low_thresh = 0; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 722 | nf_ct_frag6_evictor(); |
| 723 | } |