Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * INET An implementation of the TCP/IP protocol suite for the LINUX |
| 3 | * operating system. INET is implemented using the BSD Socket |
| 4 | * interface as the means of communication with the user level. |
| 5 | * |
| 6 | * The Internet Protocol (IP) output module. |
| 7 | * |
Jesper Juhl | 02c30a8 | 2005-05-05 16:16:16 -0700 | [diff] [blame] | 8 | * Authors: Ross Biro |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 9 | * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> |
| 10 | * Donald Becker, <becker@super.org> |
| 11 | * Alan Cox, <Alan.Cox@linux.org> |
| 12 | * Richard Underwood |
| 13 | * Stefan Becker, <stefanb@yello.ping.de> |
| 14 | * Jorge Cwik, <jorge@laser.satlink.net> |
| 15 | * Arnt Gulbrandsen, <agulbra@nvg.unit.no> |
| 16 | * Hirokazu Takahashi, <taka@valinux.co.jp> |
| 17 | * |
| 18 | * See ip_input.c for original log |
| 19 | * |
| 20 | * Fixes: |
| 21 | * Alan Cox : Missing nonblock feature in ip_build_xmit. |
| 22 | * Mike Kilburn : htons() missing in ip_build_xmit. |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 23 | * Bradford Johnson: Fix faulty handling of some frames when |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | * no route is found. |
| 25 | * Alexander Demenshin: Missing sk/skb free in ip_queue_xmit |
| 26 | * (in case if packet not accepted by |
| 27 | * output firewall rules) |
| 28 | * Mike McLagan : Routing by source |
| 29 | * Alexey Kuznetsov: use new route cache |
| 30 | * Andi Kleen: Fix broken PMTU recovery and remove |
| 31 | * some redundant tests. |
| 32 | * Vitaly E. Lavrov : Transparent proxy revived after year coma. |
| 33 | * Andi Kleen : Replace ip_reply with ip_send_reply. |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 34 | * Andi Kleen : Split fast and slow ip_build_xmit path |
| 35 | * for decreased register pressure on x86 |
| 36 | * and more readibility. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 37 | * Marc Boucher : When call_out_firewall returns FW_QUEUE, |
| 38 | * silently drop skb instead of failing with -EPERM. |
| 39 | * Detlev Wengorz : Copy protocol for fragments. |
| 40 | * Hirokazu Takahashi: HW checksumming for outgoing UDP |
| 41 | * datagrams. |
| 42 | * Hirokazu Takahashi: sendfile() on UDP works now. |
| 43 | */ |
| 44 | |
| 45 | #include <asm/uaccess.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 46 | #include <linux/module.h> |
| 47 | #include <linux/types.h> |
| 48 | #include <linux/kernel.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 49 | #include <linux/mm.h> |
| 50 | #include <linux/string.h> |
| 51 | #include <linux/errno.h> |
Al Viro | a1f8e7f7 | 2006-10-19 16:08:53 -0400 | [diff] [blame] | 52 | #include <linux/highmem.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 53 | #include <linux/slab.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 54 | |
| 55 | #include <linux/socket.h> |
| 56 | #include <linux/sockios.h> |
| 57 | #include <linux/in.h> |
| 58 | #include <linux/inet.h> |
| 59 | #include <linux/netdevice.h> |
| 60 | #include <linux/etherdevice.h> |
| 61 | #include <linux/proc_fs.h> |
| 62 | #include <linux/stat.h> |
| 63 | #include <linux/init.h> |
| 64 | |
| 65 | #include <net/snmp.h> |
| 66 | #include <net/ip.h> |
| 67 | #include <net/protocol.h> |
| 68 | #include <net/route.h> |
Patrick McHardy | cfacb05 | 2006-01-08 22:36:54 -0800 | [diff] [blame] | 69 | #include <net/xfrm.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 70 | #include <linux/skbuff.h> |
| 71 | #include <net/sock.h> |
| 72 | #include <net/arp.h> |
| 73 | #include <net/icmp.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 74 | #include <net/checksum.h> |
| 75 | #include <net/inetpeer.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 76 | #include <linux/igmp.h> |
| 77 | #include <linux/netfilter_ipv4.h> |
| 78 | #include <linux/netfilter_bridge.h> |
| 79 | #include <linux/mroute.h> |
| 80 | #include <linux/netlink.h> |
Arnaldo Carvalho de Melo | 6cbb0df | 2005-08-09 19:49:02 -0700 | [diff] [blame] | 81 | #include <linux/tcp.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 82 | |
Brian Haley | ab32ea5 | 2006-09-22 14:15:41 -0700 | [diff] [blame] | 83 | int sysctl_ip_default_ttl __read_mostly = IPDEFTTL; |
David S. Miller | 323e126 | 2010-12-12 21:55:08 -0800 | [diff] [blame] | 84 | EXPORT_SYMBOL(sysctl_ip_default_ttl); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 85 | |
| 86 | /* Generate a checksum for an outgoing IP datagram. */ |
Denis Efremov | 2fbd967 | 2013-05-08 23:19:42 +0000 | [diff] [blame] | 87 | void ip_send_check(struct iphdr *iph) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 88 | { |
| 89 | iph->check = 0; |
| 90 | iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl); |
| 91 | } |
Eric Dumazet | 4bc2f18 | 2010-07-09 21:22:10 +0000 | [diff] [blame] | 92 | EXPORT_SYMBOL(ip_send_check); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 93 | |
Herbert Xu | c439cb2 | 2008-01-11 19:14:00 -0800 | [diff] [blame] | 94 | int __ip_local_out(struct sk_buff *skb) |
| 95 | { |
| 96 | struct iphdr *iph = ip_hdr(skb); |
| 97 | |
| 98 | iph->tot_len = htons(skb->len); |
| 99 | ip_send_check(iph); |
Jan Engelhardt | 9bbc768 | 2010-03-23 04:07:29 +0100 | [diff] [blame] | 100 | return nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, skb, NULL, |
| 101 | skb_dst(skb)->dev, dst_output); |
Herbert Xu | c439cb2 | 2008-01-11 19:14:00 -0800 | [diff] [blame] | 102 | } |
| 103 | |
| 104 | int ip_local_out(struct sk_buff *skb) |
| 105 | { |
| 106 | int err; |
| 107 | |
| 108 | err = __ip_local_out(skb); |
| 109 | if (likely(err == 1)) |
| 110 | err = dst_output(skb); |
| 111 | |
| 112 | return err; |
| 113 | } |
| 114 | EXPORT_SYMBOL_GPL(ip_local_out); |
| 115 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | static inline int ip_select_ttl(struct inet_sock *inet, struct dst_entry *dst) |
| 117 | { |
| 118 | int ttl = inet->uc_ttl; |
| 119 | |
| 120 | if (ttl < 0) |
David S. Miller | 323e126 | 2010-12-12 21:55:08 -0800 | [diff] [blame] | 121 | ttl = ip4_dst_hoplimit(dst); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 122 | return ttl; |
| 123 | } |
| 124 | |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 125 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 126 | * Add an ip header to a skbuff and send it out. |
| 127 | * |
| 128 | */ |
| 129 | int ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk, |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 130 | __be32 saddr, __be32 daddr, struct ip_options_rcu *opt) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 131 | { |
| 132 | struct inet_sock *inet = inet_sk(sk); |
Eric Dumazet | 511c3f9 | 2009-06-02 05:14:27 +0000 | [diff] [blame] | 133 | struct rtable *rt = skb_rtable(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 134 | struct iphdr *iph; |
| 135 | |
| 136 | /* Build the IP header. */ |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 137 | skb_push(skb, sizeof(struct iphdr) + (opt ? opt->opt.optlen : 0)); |
Arnaldo Carvalho de Melo | 8856dfa | 2007-03-10 19:40:39 -0300 | [diff] [blame] | 138 | skb_reset_network_header(skb); |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 139 | iph = ip_hdr(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 140 | iph->version = 4; |
| 141 | iph->ihl = 5; |
| 142 | iph->tos = inet->tos; |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 143 | if (ip_dont_fragment(sk, &rt->dst)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 144 | iph->frag_off = htons(IP_DF); |
| 145 | else |
| 146 | iph->frag_off = 0; |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 147 | iph->ttl = ip_select_ttl(inet, &rt->dst); |
David S. Miller | dd927a2 | 2011-05-04 12:03:30 -0700 | [diff] [blame] | 148 | iph->daddr = (opt && opt->opt.srr ? opt->opt.faddr : daddr); |
| 149 | iph->saddr = saddr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 150 | iph->protocol = sk->sk_protocol; |
Ansis Atteka | 703133d | 2013-09-18 15:29:53 -0700 | [diff] [blame] | 151 | ip_select_ident(skb, &rt->dst, sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 153 | if (opt && opt->opt.optlen) { |
| 154 | iph->ihl += opt->opt.optlen>>2; |
| 155 | ip_options_build(skb, &opt->opt, daddr, rt, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 156 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 157 | |
| 158 | skb->priority = sk->sk_priority; |
Laszlo Attila Toth | 4a19ec5 | 2008-01-30 19:08:16 -0800 | [diff] [blame] | 159 | skb->mark = sk->sk_mark; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 160 | |
| 161 | /* Send it out. */ |
Herbert Xu | c439cb2 | 2008-01-11 19:14:00 -0800 | [diff] [blame] | 162 | return ip_local_out(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 163 | } |
Arnaldo Carvalho de Melo | d8c97a9 | 2005-08-09 20:12:12 -0700 | [diff] [blame] | 164 | EXPORT_SYMBOL_GPL(ip_build_and_send_pkt); |
| 165 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 166 | static inline int ip_finish_output2(struct sk_buff *skb) |
| 167 | { |
Eric Dumazet | adf3090 | 2009-06-02 05:19:30 +0000 | [diff] [blame] | 168 | struct dst_entry *dst = skb_dst(skb); |
Mitsuru Chinen | 80787eb | 2007-04-30 00:48:20 -0700 | [diff] [blame] | 169 | struct rtable *rt = (struct rtable *)dst; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 170 | struct net_device *dev = dst->dev; |
Chuck Lever | c2636b4 | 2007-10-23 21:07:32 -0700 | [diff] [blame] | 171 | unsigned int hh_len = LL_RESERVED_SPACE(dev); |
David S. Miller | f6b72b6 | 2011-07-14 07:53:20 -0700 | [diff] [blame] | 172 | struct neighbour *neigh; |
David S. Miller | a263b30 | 2012-07-02 02:02:15 -0700 | [diff] [blame] | 173 | u32 nexthop; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 174 | |
Neil Horman | edf391f | 2009-04-27 02:45:02 -0700 | [diff] [blame] | 175 | if (rt->rt_type == RTN_MULTICAST) { |
| 176 | IP_UPD_PO_STATS(dev_net(dev), IPSTATS_MIB_OUTMCAST, skb->len); |
| 177 | } else if (rt->rt_type == RTN_BROADCAST) |
| 178 | IP_UPD_PO_STATS(dev_net(dev), IPSTATS_MIB_OUTBCAST, skb->len); |
Mitsuru Chinen | 80787eb | 2007-04-30 00:48:20 -0700 | [diff] [blame] | 179 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 180 | /* Be paranoid, rather than too clever. */ |
Stephen Hemminger | 3b04ddd | 2007-10-09 01:40:57 -0700 | [diff] [blame] | 181 | if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 182 | struct sk_buff *skb2; |
| 183 | |
| 184 | skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev)); |
| 185 | if (skb2 == NULL) { |
| 186 | kfree_skb(skb); |
| 187 | return -ENOMEM; |
| 188 | } |
| 189 | if (skb->sk) |
| 190 | skb_set_owner_w(skb2, skb->sk); |
Eric Dumazet | 5d0ba55 | 2012-06-04 01:17:19 +0000 | [diff] [blame] | 191 | consume_skb(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 192 | skb = skb2; |
| 193 | } |
| 194 | |
David S. Miller | a263b30 | 2012-07-02 02:02:15 -0700 | [diff] [blame] | 195 | rcu_read_lock_bh(); |
Julian Anastasov | 155e833 | 2012-10-08 11:41:18 +0000 | [diff] [blame] | 196 | nexthop = (__force u32) rt_nexthop(rt, ip_hdr(skb)->daddr); |
David S. Miller | a263b30 | 2012-07-02 02:02:15 -0700 | [diff] [blame] | 197 | neigh = __ipv4_neigh_lookup_noref(dev, nexthop); |
| 198 | if (unlikely(!neigh)) |
| 199 | neigh = __neigh_create(&arp_tbl, &nexthop, dev, false); |
Vasiliy Kulikov | 9871f1a | 2012-08-06 03:55:29 +0000 | [diff] [blame] | 200 | if (!IS_ERR(neigh)) { |
David S. Miller | 5110effe | 2012-07-02 02:21:03 -0700 | [diff] [blame] | 201 | int res = dst_neigh_output(dst, neigh, skb); |
Eric Dumazet | f2c31e3 | 2011-07-29 19:00:53 +0000 | [diff] [blame] | 202 | |
David S. Miller | a263b30 | 2012-07-02 02:02:15 -0700 | [diff] [blame] | 203 | rcu_read_unlock_bh(); |
Eric Dumazet | f2c31e3 | 2011-07-29 19:00:53 +0000 | [diff] [blame] | 204 | return res; |
| 205 | } |
David S. Miller | a263b30 | 2012-07-02 02:02:15 -0700 | [diff] [blame] | 206 | rcu_read_unlock_bh(); |
David S. Miller | 05e3aa0 | 2011-07-16 17:26:00 -0700 | [diff] [blame] | 207 | |
Joe Perches | e87cc47 | 2012-05-13 21:56:26 +0000 | [diff] [blame] | 208 | net_dbg_ratelimited("%s: No header cache and no neighbour!\n", |
| 209 | __func__); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 210 | kfree_skb(skb); |
| 211 | return -EINVAL; |
| 212 | } |
| 213 | |
Patrick McHardy | 861d048 | 2007-10-15 01:48:39 -0700 | [diff] [blame] | 214 | static int ip_finish_output(struct sk_buff *skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 215 | { |
Patrick McHardy | 5c901da | 2006-01-06 23:05:36 -0800 | [diff] [blame] | 216 | #if defined(CONFIG_NETFILTER) && defined(CONFIG_XFRM) |
| 217 | /* Policy lookup after SNAT yielded a new policy */ |
Eric Dumazet | adf3090 | 2009-06-02 05:19:30 +0000 | [diff] [blame] | 218 | if (skb_dst(skb)->xfrm != NULL) { |
Patrick McHardy | 48d5cad | 2006-02-15 15:10:22 -0800 | [diff] [blame] | 219 | IPCB(skb)->flags |= IPSKB_REROUTED; |
| 220 | return dst_output(skb); |
| 221 | } |
Patrick McHardy | 5c901da | 2006-01-06 23:05:36 -0800 | [diff] [blame] | 222 | #endif |
John Heffner | 628a5c5 | 2007-04-20 15:53:27 -0700 | [diff] [blame] | 223 | if (skb->len > ip_skb_dst_mtu(skb) && !skb_is_gso(skb)) |
Patrick McHardy | 1bd9bef | 2006-01-05 12:20:59 -0800 | [diff] [blame] | 224 | return ip_fragment(skb, ip_finish_output2); |
| 225 | else |
| 226 | return ip_finish_output2(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 227 | } |
| 228 | |
| 229 | int ip_mc_output(struct sk_buff *skb) |
| 230 | { |
| 231 | struct sock *sk = skb->sk; |
Eric Dumazet | 511c3f9 | 2009-06-02 05:14:27 +0000 | [diff] [blame] | 232 | struct rtable *rt = skb_rtable(skb); |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 233 | struct net_device *dev = rt->dst.dev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 234 | |
| 235 | /* |
| 236 | * If the indicated interface is up and running, send the packet. |
| 237 | */ |
Neil Horman | edf391f | 2009-04-27 02:45:02 -0700 | [diff] [blame] | 238 | IP_UPD_PO_STATS(dev_net(dev), IPSTATS_MIB_OUT, skb->len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 239 | |
| 240 | skb->dev = dev; |
| 241 | skb->protocol = htons(ETH_P_IP); |
| 242 | |
| 243 | /* |
| 244 | * Multicasts are looped back for other local users |
| 245 | */ |
| 246 | |
| 247 | if (rt->rt_flags&RTCF_MULTICAST) { |
Octavian Purdila | 7ad6848 | 2010-01-06 20:37:01 -0800 | [diff] [blame] | 248 | if (sk_mc_loop(sk) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 249 | #ifdef CONFIG_IP_MROUTE |
| 250 | /* Small optimization: do not loopback not local frames, |
| 251 | which returned after forwarding; they will be dropped |
| 252 | by ip_mr_input in any case. |
| 253 | Note, that local frames are looped back to be delivered |
| 254 | to local recipients. |
| 255 | |
| 256 | This check is duplicated in ip_mr_input at the moment. |
| 257 | */ |
Joe Perches | 9d4fb27 | 2009-11-23 10:41:23 -0800 | [diff] [blame] | 258 | && |
| 259 | ((rt->rt_flags & RTCF_LOCAL) || |
| 260 | !(IPCB(skb)->flags & IPSKB_FORWARDED)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 261 | #endif |
Joe Perches | 9d4fb27 | 2009-11-23 10:41:23 -0800 | [diff] [blame] | 262 | ) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 263 | struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC); |
| 264 | if (newskb) |
Jan Engelhardt | 9bbc768 | 2010-03-23 04:07:29 +0100 | [diff] [blame] | 265 | NF_HOOK(NFPROTO_IPV4, NF_INET_POST_ROUTING, |
| 266 | newskb, NULL, newskb->dev, |
Michel Machado | 95603e2 | 2012-06-12 10:16:35 +0000 | [diff] [blame] | 267 | dev_loopback_xmit); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 268 | } |
| 269 | |
| 270 | /* Multicasts with ttl 0 must not go beyond the host */ |
| 271 | |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 272 | if (ip_hdr(skb)->ttl == 0) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 273 | kfree_skb(skb); |
| 274 | return 0; |
| 275 | } |
| 276 | } |
| 277 | |
| 278 | if (rt->rt_flags&RTCF_BROADCAST) { |
| 279 | struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC); |
| 280 | if (newskb) |
Jan Engelhardt | 9bbc768 | 2010-03-23 04:07:29 +0100 | [diff] [blame] | 281 | NF_HOOK(NFPROTO_IPV4, NF_INET_POST_ROUTING, newskb, |
Michel Machado | 95603e2 | 2012-06-12 10:16:35 +0000 | [diff] [blame] | 282 | NULL, newskb->dev, dev_loopback_xmit); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 283 | } |
| 284 | |
Jan Engelhardt | 9bbc768 | 2010-03-23 04:07:29 +0100 | [diff] [blame] | 285 | return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING, skb, NULL, |
| 286 | skb->dev, ip_finish_output, |
Patrick McHardy | 48d5cad | 2006-02-15 15:10:22 -0800 | [diff] [blame] | 287 | !(IPCB(skb)->flags & IPSKB_REROUTED)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 288 | } |
| 289 | |
| 290 | int ip_output(struct sk_buff *skb) |
| 291 | { |
Eric Dumazet | adf3090 | 2009-06-02 05:19:30 +0000 | [diff] [blame] | 292 | struct net_device *dev = skb_dst(skb)->dev; |
Patrick McHardy | 1bd9bef | 2006-01-05 12:20:59 -0800 | [diff] [blame] | 293 | |
Neil Horman | edf391f | 2009-04-27 02:45:02 -0700 | [diff] [blame] | 294 | IP_UPD_PO_STATS(dev_net(dev), IPSTATS_MIB_OUT, skb->len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 295 | |
Patrick McHardy | 1bd9bef | 2006-01-05 12:20:59 -0800 | [diff] [blame] | 296 | skb->dev = dev; |
| 297 | skb->protocol = htons(ETH_P_IP); |
| 298 | |
Jan Engelhardt | 9bbc768 | 2010-03-23 04:07:29 +0100 | [diff] [blame] | 299 | return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING, skb, NULL, dev, |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 300 | ip_finish_output, |
Patrick McHardy | 48d5cad | 2006-02-15 15:10:22 -0800 | [diff] [blame] | 301 | !(IPCB(skb)->flags & IPSKB_REROUTED)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 302 | } |
| 303 | |
Eric Dumazet | 84f9307 | 2011-11-30 19:00:53 +0000 | [diff] [blame] | 304 | /* |
| 305 | * copy saddr and daddr, possibly using 64bit load/stores |
| 306 | * Equivalent to : |
| 307 | * iph->saddr = fl4->saddr; |
| 308 | * iph->daddr = fl4->daddr; |
| 309 | */ |
| 310 | static void ip_copy_addrs(struct iphdr *iph, const struct flowi4 *fl4) |
| 311 | { |
| 312 | BUILD_BUG_ON(offsetof(typeof(*fl4), daddr) != |
| 313 | offsetof(typeof(*fl4), saddr) + sizeof(fl4->saddr)); |
| 314 | memcpy(&iph->saddr, &fl4->saddr, |
| 315 | sizeof(fl4->saddr) + sizeof(fl4->daddr)); |
| 316 | } |
| 317 | |
David S. Miller | d9d8da8 | 2011-05-06 22:23:20 -0700 | [diff] [blame] | 318 | int ip_queue_xmit(struct sk_buff *skb, struct flowi *fl) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 319 | { |
David S. Miller | e89862f | 2007-01-26 01:04:55 -0800 | [diff] [blame] | 320 | struct sock *sk = skb->sk; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 321 | struct inet_sock *inet = inet_sk(sk); |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 322 | struct ip_options_rcu *inet_opt; |
David S. Miller | b57ae01 | 2011-05-06 16:24:06 -0700 | [diff] [blame] | 323 | struct flowi4 *fl4; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 324 | struct rtable *rt; |
| 325 | struct iphdr *iph; |
Eric Dumazet | ab6e3fe | 2010-05-10 11:31:49 +0000 | [diff] [blame] | 326 | int res; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 327 | |
| 328 | /* Skip all of this if the packet is already routed, |
| 329 | * f.e. by something like SCTP. |
| 330 | */ |
Eric Dumazet | ab6e3fe | 2010-05-10 11:31:49 +0000 | [diff] [blame] | 331 | rcu_read_lock(); |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 332 | inet_opt = rcu_dereference(inet->inet_opt); |
David S. Miller | ea4fc0d | 2011-05-06 22:30:20 -0700 | [diff] [blame] | 333 | fl4 = &fl->u.ip4; |
Eric Dumazet | 511c3f9 | 2009-06-02 05:14:27 +0000 | [diff] [blame] | 334 | rt = skb_rtable(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 335 | if (rt != NULL) |
| 336 | goto packet_routed; |
| 337 | |
| 338 | /* Make sure we can route this packet. */ |
| 339 | rt = (struct rtable *)__sk_dst_check(sk, 0); |
| 340 | if (rt == NULL) { |
Al Viro | 3ca3c68 | 2006-09-27 18:28:07 -0700 | [diff] [blame] | 341 | __be32 daddr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 342 | |
| 343 | /* Use correct destination address if we have options. */ |
Eric Dumazet | c720c7e | 2009-10-15 06:30:45 +0000 | [diff] [blame] | 344 | daddr = inet->inet_daddr; |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 345 | if (inet_opt && inet_opt->opt.srr) |
| 346 | daddr = inet_opt->opt.faddr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 347 | |
David S. Miller | 78fbfd8 | 2011-03-12 00:00:52 -0500 | [diff] [blame] | 348 | /* If this fails, retransmit mechanism of transport layer will |
| 349 | * keep trying until route appears or the connection times |
| 350 | * itself out. |
| 351 | */ |
David S. Miller | b57ae01 | 2011-05-06 16:24:06 -0700 | [diff] [blame] | 352 | rt = ip_route_output_ports(sock_net(sk), fl4, sk, |
David S. Miller | 78fbfd8 | 2011-03-12 00:00:52 -0500 | [diff] [blame] | 353 | daddr, inet->inet_saddr, |
| 354 | inet->inet_dport, |
| 355 | inet->inet_sport, |
| 356 | sk->sk_protocol, |
| 357 | RT_CONN_FLAGS(sk), |
| 358 | sk->sk_bound_dev_if); |
| 359 | if (IS_ERR(rt)) |
| 360 | goto no_route; |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 361 | sk_setup_caps(sk, &rt->dst); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 362 | } |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 363 | skb_dst_set_noref(skb, &rt->dst); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 364 | |
| 365 | packet_routed: |
Julian Anastasov | 155e833 | 2012-10-08 11:41:18 +0000 | [diff] [blame] | 366 | if (inet_opt && inet_opt->opt.is_strictroute && rt->rt_uses_gateway) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 367 | goto no_route; |
| 368 | |
| 369 | /* OK, we know where to send it, allocate and build IP header. */ |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 370 | skb_push(skb, sizeof(struct iphdr) + (inet_opt ? inet_opt->opt.optlen : 0)); |
Arnaldo Carvalho de Melo | 8856dfa | 2007-03-10 19:40:39 -0300 | [diff] [blame] | 371 | skb_reset_network_header(skb); |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 372 | iph = ip_hdr(skb); |
Al Viro | 714e85b | 2006-11-14 20:51:49 -0800 | [diff] [blame] | 373 | *((__be16 *)iph) = htons((4 << 12) | (5 << 8) | (inet->tos & 0xff)); |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 374 | if (ip_dont_fragment(sk, &rt->dst) && !skb->local_df) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 375 | iph->frag_off = htons(IP_DF); |
| 376 | else |
| 377 | iph->frag_off = 0; |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 378 | iph->ttl = ip_select_ttl(inet, &rt->dst); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 379 | iph->protocol = sk->sk_protocol; |
Eric Dumazet | 84f9307 | 2011-11-30 19:00:53 +0000 | [diff] [blame] | 380 | ip_copy_addrs(iph, fl4); |
| 381 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 382 | /* Transport layer set skb->h.foo itself. */ |
| 383 | |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 384 | if (inet_opt && inet_opt->opt.optlen) { |
| 385 | iph->ihl += inet_opt->opt.optlen >> 2; |
| 386 | ip_options_build(skb, &inet_opt->opt, inet->inet_daddr, rt, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 387 | } |
| 388 | |
Ansis Atteka | 703133d | 2013-09-18 15:29:53 -0700 | [diff] [blame] | 389 | ip_select_ident_more(skb, &rt->dst, sk, |
Herbert Xu | 7967168 | 2006-06-22 02:40:14 -0700 | [diff] [blame] | 390 | (skb_shinfo(skb)->gso_segs ?: 1) - 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 391 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 392 | skb->priority = sk->sk_priority; |
Laszlo Attila Toth | 4a19ec5 | 2008-01-30 19:08:16 -0800 | [diff] [blame] | 393 | skb->mark = sk->sk_mark; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 394 | |
Eric Dumazet | ab6e3fe | 2010-05-10 11:31:49 +0000 | [diff] [blame] | 395 | res = ip_local_out(skb); |
| 396 | rcu_read_unlock(); |
| 397 | return res; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 398 | |
| 399 | no_route: |
Eric Dumazet | ab6e3fe | 2010-05-10 11:31:49 +0000 | [diff] [blame] | 400 | rcu_read_unlock(); |
Pavel Emelyanov | 5e38e27 | 2008-07-16 20:19:49 -0700 | [diff] [blame] | 401 | IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 402 | kfree_skb(skb); |
| 403 | return -EHOSTUNREACH; |
| 404 | } |
Eric Dumazet | 4bc2f18 | 2010-07-09 21:22:10 +0000 | [diff] [blame] | 405 | EXPORT_SYMBOL(ip_queue_xmit); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 406 | |
| 407 | |
| 408 | static void ip_copy_metadata(struct sk_buff *to, struct sk_buff *from) |
| 409 | { |
| 410 | to->pkt_type = from->pkt_type; |
| 411 | to->priority = from->priority; |
| 412 | to->protocol = from->protocol; |
Eric Dumazet | adf3090 | 2009-06-02 05:19:30 +0000 | [diff] [blame] | 413 | skb_dst_drop(to); |
Eric Dumazet | fe76cda | 2010-07-01 23:48:22 +0000 | [diff] [blame] | 414 | skb_dst_copy(to, from); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 415 | to->dev = from->dev; |
Thomas Graf | 82e91ff | 2006-11-09 15:19:14 -0800 | [diff] [blame] | 416 | to->mark = from->mark; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 417 | |
| 418 | /* Copy the flags to each fragment. */ |
| 419 | IPCB(to)->flags = IPCB(from)->flags; |
| 420 | |
| 421 | #ifdef CONFIG_NET_SCHED |
| 422 | to->tc_index = from->tc_index; |
| 423 | #endif |
Yasuyuki Kozakai | e7ac05f | 2007-03-14 16:44:01 -0700 | [diff] [blame] | 424 | nf_copy(to, from); |
Julian Anastasov | c98d80e | 2005-10-22 13:39:21 +0300 | [diff] [blame] | 425 | #if defined(CONFIG_IP_VS) || defined(CONFIG_IP_VS_MODULE) |
| 426 | to->ipvs_property = from->ipvs_property; |
| 427 | #endif |
James Morris | 984bc16 | 2006-06-09 00:29:17 -0700 | [diff] [blame] | 428 | skb_copy_secmark(to, from); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 429 | } |
| 430 | |
| 431 | /* |
| 432 | * This IP datagram is too large to be sent in one piece. Break it up into |
| 433 | * smaller pieces (each of size equal to IP header plus |
| 434 | * a block of the data of the original IP data part) that will yet fit in a |
| 435 | * single device frame, and queue such a frame for sending. |
| 436 | */ |
| 437 | |
Jianjun Kong | d9319100 | 2008-11-03 00:23:42 -0800 | [diff] [blame] | 438 | int ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 439 | { |
| 440 | struct iphdr *iph; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 441 | int ptr; |
| 442 | struct net_device *dev; |
| 443 | struct sk_buff *skb2; |
Changli Gao | c893b80 | 2010-07-31 13:25:08 +0000 | [diff] [blame] | 444 | unsigned int mtu, hlen, left, len, ll_rs; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 445 | int offset; |
Alexey Dobriyan | 76ab608 | 2006-01-06 13:24:29 -0800 | [diff] [blame] | 446 | __be16 not_last_frag; |
Eric Dumazet | 511c3f9 | 2009-06-02 05:14:27 +0000 | [diff] [blame] | 447 | struct rtable *rt = skb_rtable(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 448 | int err = 0; |
| 449 | |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 450 | dev = rt->dst.dev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 451 | |
| 452 | /* |
| 453 | * Point into the IP datagram header. |
| 454 | */ |
| 455 | |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 456 | iph = ip_hdr(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 457 | |
Hannes Frederic Sowa | 69647ce | 2014-02-26 01:20:41 +0100 | [diff] [blame] | 458 | mtu = ip_skb_dst_mtu(skb); |
Patrick McHardy | 5f2d04f | 2012-08-26 19:13:55 +0200 | [diff] [blame] | 459 | if (unlikely(((iph->frag_off & htons(IP_DF)) && !skb->local_df) || |
| 460 | (IPCB(skb)->frag_max_size && |
Hannes Frederic Sowa | f87c10a | 2014-01-09 10:01:15 +0100 | [diff] [blame] | 461 | IPCB(skb)->frag_max_size > mtu))) { |
Pavel Emelyanov | 5e38e27 | 2008-07-16 20:19:49 -0700 | [diff] [blame] | 462 | IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGFAILS); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 463 | icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, |
Hannes Frederic Sowa | f87c10a | 2014-01-09 10:01:15 +0100 | [diff] [blame] | 464 | htonl(mtu)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 465 | kfree_skb(skb); |
| 466 | return -EMSGSIZE; |
| 467 | } |
| 468 | |
| 469 | /* |
| 470 | * Setup starting values. |
| 471 | */ |
| 472 | |
| 473 | hlen = iph->ihl * 4; |
Hannes Frederic Sowa | f87c10a | 2014-01-09 10:01:15 +0100 | [diff] [blame] | 474 | mtu = mtu - hlen; /* Size of data space */ |
Bart De Schuymer | 6c79bf0 | 2010-04-20 16:22:01 +0200 | [diff] [blame] | 475 | #ifdef CONFIG_BRIDGE_NETFILTER |
| 476 | if (skb->nf_bridge) |
| 477 | mtu -= nf_bridge_mtu_reduction(skb); |
| 478 | #endif |
Herbert Xu | 89cee8b | 2005-12-13 23:14:27 -0800 | [diff] [blame] | 479 | IPCB(skb)->flags |= IPSKB_FRAG_COMPLETE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 480 | |
| 481 | /* When frag_list is given, use it. First, check its validity: |
| 482 | * some transformers could create wrong frag_list or break existing |
| 483 | * one, it is not prohibited. In this case fall back to copying. |
| 484 | * |
| 485 | * LATER: this step can be merged to real generation of fragments, |
| 486 | * we can switch to copy when see the first bad fragment. |
| 487 | */ |
David S. Miller | 21dc330 | 2010-08-23 00:13:46 -0700 | [diff] [blame] | 488 | if (skb_has_frag_list(skb)) { |
Eric Dumazet | 3d13008 | 2010-09-21 08:47:45 +0000 | [diff] [blame] | 489 | struct sk_buff *frag, *frag2; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 490 | int first_len = skb_pagelen(skb); |
| 491 | |
| 492 | if (first_len - hlen > mtu || |
| 493 | ((first_len - hlen) & 7) || |
Paul Gortmaker | 56f8a75 | 2011-06-21 20:33:34 -0700 | [diff] [blame] | 494 | ip_is_fragment(iph) || |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 495 | skb_cloned(skb)) |
| 496 | goto slow_path; |
| 497 | |
David S. Miller | d7fcf1a | 2009-06-09 00:19:37 -0700 | [diff] [blame] | 498 | skb_walk_frags(skb, frag) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 499 | /* Correct geometry. */ |
| 500 | if (frag->len > mtu || |
| 501 | ((frag->len & 7) && frag->next) || |
| 502 | skb_headroom(frag) < hlen) |
Eric Dumazet | 3d13008 | 2010-09-21 08:47:45 +0000 | [diff] [blame] | 503 | goto slow_path_clean; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 504 | |
| 505 | /* Partially cloned skb? */ |
| 506 | if (skb_shared(frag)) |
Eric Dumazet | 3d13008 | 2010-09-21 08:47:45 +0000 | [diff] [blame] | 507 | goto slow_path_clean; |
Herbert Xu | 2fdba6b | 2005-05-18 22:52:33 -0700 | [diff] [blame] | 508 | |
| 509 | BUG_ON(frag->sk); |
| 510 | if (skb->sk) { |
Herbert Xu | 2fdba6b | 2005-05-18 22:52:33 -0700 | [diff] [blame] | 511 | frag->sk = skb->sk; |
| 512 | frag->destructor = sock_wfree; |
Herbert Xu | 2fdba6b | 2005-05-18 22:52:33 -0700 | [diff] [blame] | 513 | } |
Eric Dumazet | 3d13008 | 2010-09-21 08:47:45 +0000 | [diff] [blame] | 514 | skb->truesize -= frag->truesize; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 515 | } |
| 516 | |
| 517 | /* Everything is OK. Generate! */ |
| 518 | |
| 519 | err = 0; |
| 520 | offset = 0; |
| 521 | frag = skb_shinfo(skb)->frag_list; |
David S. Miller | d7fcf1a | 2009-06-09 00:19:37 -0700 | [diff] [blame] | 522 | skb_frag_list_init(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 523 | skb->data_len = first_len - skb_headlen(skb); |
| 524 | skb->len = first_len; |
| 525 | iph->tot_len = htons(first_len); |
| 526 | iph->frag_off = htons(IP_MF); |
| 527 | ip_send_check(iph); |
| 528 | |
| 529 | for (;;) { |
| 530 | /* Prepare header of the next frame, |
| 531 | * before previous one went down. */ |
| 532 | if (frag) { |
| 533 | frag->ip_summed = CHECKSUM_NONE; |
Arnaldo Carvalho de Melo | badff6d | 2007-03-13 13:06:52 -0300 | [diff] [blame] | 534 | skb_reset_transport_header(frag); |
Arnaldo Carvalho de Melo | e2d1bca | 2007-04-10 20:46:21 -0700 | [diff] [blame] | 535 | __skb_push(frag, hlen); |
| 536 | skb_reset_network_header(frag); |
Arnaldo Carvalho de Melo | d56f90a | 2007-04-10 20:50:43 -0700 | [diff] [blame] | 537 | memcpy(skb_network_header(frag), iph, hlen); |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 538 | iph = ip_hdr(frag); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 539 | iph->tot_len = htons(frag->len); |
| 540 | ip_copy_metadata(frag, skb); |
| 541 | if (offset == 0) |
| 542 | ip_options_fragment(frag); |
| 543 | offset += skb->len - hlen; |
| 544 | iph->frag_off = htons(offset>>3); |
| 545 | if (frag->next != NULL) |
| 546 | iph->frag_off |= htons(IP_MF); |
| 547 | /* Ready, complete checksum */ |
| 548 | ip_send_check(iph); |
| 549 | } |
| 550 | |
| 551 | err = output(skb); |
| 552 | |
Wei Dong | dafee49 | 2006-08-02 13:41:21 -0700 | [diff] [blame] | 553 | if (!err) |
Pavel Emelyanov | 5e38e27 | 2008-07-16 20:19:49 -0700 | [diff] [blame] | 554 | IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGCREATES); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 555 | if (err || !frag) |
| 556 | break; |
| 557 | |
| 558 | skb = frag; |
| 559 | frag = skb->next; |
| 560 | skb->next = NULL; |
| 561 | } |
| 562 | |
| 563 | if (err == 0) { |
Pavel Emelyanov | 5e38e27 | 2008-07-16 20:19:49 -0700 | [diff] [blame] | 564 | IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGOKS); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 565 | return 0; |
| 566 | } |
| 567 | |
| 568 | while (frag) { |
| 569 | skb = frag->next; |
| 570 | kfree_skb(frag); |
| 571 | frag = skb; |
| 572 | } |
Pavel Emelyanov | 5e38e27 | 2008-07-16 20:19:49 -0700 | [diff] [blame] | 573 | IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGFAILS); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 574 | return err; |
Eric Dumazet | 3d13008 | 2010-09-21 08:47:45 +0000 | [diff] [blame] | 575 | |
| 576 | slow_path_clean: |
| 577 | skb_walk_frags(skb, frag2) { |
| 578 | if (frag2 == frag) |
| 579 | break; |
| 580 | frag2->sk = NULL; |
| 581 | frag2->destructor = NULL; |
| 582 | skb->truesize += frag2->truesize; |
| 583 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 584 | } |
| 585 | |
| 586 | slow_path: |
Alexander Duyck | fc70fb6 | 2012-12-07 14:14:15 +0000 | [diff] [blame] | 587 | /* for offloaded checksums cleanup checksum before fragmentation */ |
| 588 | if ((skb->ip_summed == CHECKSUM_PARTIAL) && skb_checksum_help(skb)) |
| 589 | goto fail; |
Pravin B Shelar | c9af6db | 2013-02-11 09:27:41 +0000 | [diff] [blame] | 590 | iph = ip_hdr(skb); |
Alexander Duyck | fc70fb6 | 2012-12-07 14:14:15 +0000 | [diff] [blame] | 591 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 592 | left = skb->len - hlen; /* Space per frame */ |
George Kadianakis | 49085bd | 2010-07-06 11:44:12 +0000 | [diff] [blame] | 593 | ptr = hlen; /* Where to start from */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 594 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 595 | /* for bridged IP traffic encapsulated inside f.e. a vlan header, |
Stephen Hemminger | 9bcfcaf | 2006-08-29 17:48:57 -0700 | [diff] [blame] | 596 | * we need to make room for the encapsulating header |
| 597 | */ |
Changli Gao | c893b80 | 2010-07-31 13:25:08 +0000 | [diff] [blame] | 598 | ll_rs = LL_RESERVED_SPACE_EXTRA(rt->dst.dev, nf_bridge_pad(skb)); |
Stephen Hemminger | 9bcfcaf | 2006-08-29 17:48:57 -0700 | [diff] [blame] | 599 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 600 | /* |
| 601 | * Fragment the datagram. |
| 602 | */ |
| 603 | |
| 604 | offset = (ntohs(iph->frag_off) & IP_OFFSET) << 3; |
| 605 | not_last_frag = iph->frag_off & htons(IP_MF); |
| 606 | |
| 607 | /* |
| 608 | * Keep copying data until we run out. |
| 609 | */ |
| 610 | |
Stephen Hemminger | 132adf5 | 2007-03-08 20:44:43 -0800 | [diff] [blame] | 611 | while (left > 0) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 612 | len = left; |
| 613 | /* IF: it doesn't fit, use 'mtu' - the data space left */ |
| 614 | if (len > mtu) |
| 615 | len = mtu; |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 616 | /* IF: we are not sending up to and including the packet end |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 617 | then align the next start on an eight byte boundary */ |
| 618 | if (len < left) { |
| 619 | len &= ~7; |
| 620 | } |
| 621 | /* |
| 622 | * Allocate buffer. |
| 623 | */ |
| 624 | |
| 625 | if ((skb2 = alloc_skb(len+hlen+ll_rs, GFP_ATOMIC)) == NULL) { |
Patrick McHardy | 64ce207 | 2005-08-09 20:50:53 -0700 | [diff] [blame] | 626 | NETDEBUG(KERN_INFO "IP: frag: no memory for new fragment!\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 627 | err = -ENOMEM; |
| 628 | goto fail; |
| 629 | } |
| 630 | |
| 631 | /* |
| 632 | * Set up data on packet |
| 633 | */ |
| 634 | |
| 635 | ip_copy_metadata(skb2, skb); |
| 636 | skb_reserve(skb2, ll_rs); |
| 637 | skb_put(skb2, len + hlen); |
Arnaldo Carvalho de Melo | c1d2bbe | 2007-04-10 20:45:18 -0700 | [diff] [blame] | 638 | skb_reset_network_header(skb2); |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 639 | skb2->transport_header = skb2->network_header + hlen; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 640 | |
| 641 | /* |
| 642 | * Charge the memory for the fragment to any owner |
| 643 | * it might possess |
| 644 | */ |
| 645 | |
| 646 | if (skb->sk) |
| 647 | skb_set_owner_w(skb2, skb->sk); |
| 648 | |
| 649 | /* |
| 650 | * Copy the packet header into the new buffer. |
| 651 | */ |
| 652 | |
Arnaldo Carvalho de Melo | d626f62 | 2007-03-27 18:55:52 -0300 | [diff] [blame] | 653 | skb_copy_from_linear_data(skb, skb_network_header(skb2), hlen); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 654 | |
| 655 | /* |
| 656 | * Copy a block of the IP datagram. |
| 657 | */ |
Arnaldo Carvalho de Melo | bff9b61 | 2007-03-16 17:19:57 -0300 | [diff] [blame] | 658 | if (skb_copy_bits(skb, ptr, skb_transport_header(skb2), len)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 659 | BUG(); |
| 660 | left -= len; |
| 661 | |
| 662 | /* |
| 663 | * Fill in the new header fields. |
| 664 | */ |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 665 | iph = ip_hdr(skb2); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 666 | iph->frag_off = htons((offset >> 3)); |
| 667 | |
| 668 | /* ANK: dirty, but effective trick. Upgrade options only if |
| 669 | * the segment to be fragmented was THE FIRST (otherwise, |
| 670 | * options are already fixed) and make it ONCE |
| 671 | * on the initial skb, so that all the following fragments |
| 672 | * will inherit fixed options. |
| 673 | */ |
| 674 | if (offset == 0) |
| 675 | ip_options_fragment(skb); |
| 676 | |
| 677 | /* |
| 678 | * Added AC : If we are fragmenting a fragment that's not the |
| 679 | * last fragment then keep MF on each bit |
| 680 | */ |
| 681 | if (left > 0 || not_last_frag) |
| 682 | iph->frag_off |= htons(IP_MF); |
| 683 | ptr += len; |
| 684 | offset += len; |
| 685 | |
| 686 | /* |
| 687 | * Put this fragment into the sending queue. |
| 688 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 689 | iph->tot_len = htons(len + hlen); |
| 690 | |
| 691 | ip_send_check(iph); |
| 692 | |
| 693 | err = output(skb2); |
| 694 | if (err) |
| 695 | goto fail; |
Wei Dong | dafee49 | 2006-08-02 13:41:21 -0700 | [diff] [blame] | 696 | |
Pavel Emelyanov | 5e38e27 | 2008-07-16 20:19:49 -0700 | [diff] [blame] | 697 | IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGCREATES); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 698 | } |
Eric Dumazet | 5d0ba55 | 2012-06-04 01:17:19 +0000 | [diff] [blame] | 699 | consume_skb(skb); |
Pavel Emelyanov | 5e38e27 | 2008-07-16 20:19:49 -0700 | [diff] [blame] | 700 | IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGOKS); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 701 | return err; |
| 702 | |
| 703 | fail: |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 704 | kfree_skb(skb); |
Pavel Emelyanov | 5e38e27 | 2008-07-16 20:19:49 -0700 | [diff] [blame] | 705 | IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGFAILS); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 706 | return err; |
| 707 | } |
Patrick McHardy | 2e2f7ae | 2006-04-04 13:42:35 -0700 | [diff] [blame] | 708 | EXPORT_SYMBOL(ip_fragment); |
| 709 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 710 | int |
| 711 | ip_generic_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb) |
| 712 | { |
| 713 | struct iovec *iov = from; |
| 714 | |
Patrick McHardy | 84fa793 | 2006-08-29 16:44:56 -0700 | [diff] [blame] | 715 | if (skb->ip_summed == CHECKSUM_PARTIAL) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 716 | if (memcpy_fromiovecend(to, iov, offset, len) < 0) |
| 717 | return -EFAULT; |
| 718 | } else { |
Al Viro | 44bb936 | 2006-11-14 21:36:14 -0800 | [diff] [blame] | 719 | __wsum csum = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 720 | if (csum_partial_copy_fromiovecend(to, iov, offset, len, &csum) < 0) |
| 721 | return -EFAULT; |
| 722 | skb->csum = csum_block_add(skb->csum, csum, odd); |
| 723 | } |
| 724 | return 0; |
| 725 | } |
Eric Dumazet | 4bc2f18 | 2010-07-09 21:22:10 +0000 | [diff] [blame] | 726 | EXPORT_SYMBOL(ip_generic_getfrag); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 727 | |
Al Viro | 44bb936 | 2006-11-14 21:36:14 -0800 | [diff] [blame] | 728 | static inline __wsum |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 729 | csum_page(struct page *page, int offset, int copy) |
| 730 | { |
| 731 | char *kaddr; |
Al Viro | 44bb936 | 2006-11-14 21:36:14 -0800 | [diff] [blame] | 732 | __wsum csum; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 733 | kaddr = kmap(page); |
| 734 | csum = csum_partial(kaddr + offset, copy, 0); |
| 735 | kunmap(page); |
| 736 | return csum; |
| 737 | } |
| 738 | |
Adrian Bunk | 4b30b1c | 2005-11-29 16:27:20 -0800 | [diff] [blame] | 739 | static inline int ip_ufo_append_data(struct sock *sk, |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 740 | struct sk_buff_head *queue, |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 741 | int getfrag(void *from, char *to, int offset, int len, |
| 742 | int odd, struct sk_buff *skb), |
| 743 | void *from, int length, int hh_len, int fragheaderlen, |
Bill Sommerfeld | d9be4f7 | 2011-07-19 15:22:33 +0000 | [diff] [blame] | 744 | int transhdrlen, int maxfraglen, unsigned int flags) |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 745 | { |
| 746 | struct sk_buff *skb; |
| 747 | int err; |
| 748 | |
| 749 | /* There is support for UDP fragmentation offload by network |
| 750 | * device, so create one single skb packet containing complete |
| 751 | * udp datagram |
| 752 | */ |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 753 | if ((skb = skb_peek_tail(queue)) == NULL) { |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 754 | skb = sock_alloc_send_skb(sk, |
| 755 | hh_len + fragheaderlen + transhdrlen + 20, |
| 756 | (flags & MSG_DONTWAIT), &err); |
| 757 | |
| 758 | if (skb == NULL) |
| 759 | return err; |
| 760 | |
| 761 | /* reserve space for Hardware header */ |
| 762 | skb_reserve(skb, hh_len); |
| 763 | |
| 764 | /* create space for UDP/IP header */ |
Jianjun Kong | d9319100 | 2008-11-03 00:23:42 -0800 | [diff] [blame] | 765 | skb_put(skb, fragheaderlen + transhdrlen); |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 766 | |
| 767 | /* initialize network header pointer */ |
Arnaldo Carvalho de Melo | c1d2bbe | 2007-04-10 20:45:18 -0700 | [diff] [blame] | 768 | skb_reset_network_header(skb); |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 769 | |
| 770 | /* initialize protocol header pointer */ |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 771 | skb->transport_header = skb->network_header + fragheaderlen; |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 772 | |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 773 | skb->csum = 0; |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 774 | |
Jiri Pirko | e93b7d7 | 2013-10-19 12:29:17 +0200 | [diff] [blame] | 775 | |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 776 | __skb_queue_tail(queue, skb); |
Jiri Pirko | e93b7d7 | 2013-10-19 12:29:17 +0200 | [diff] [blame] | 777 | } else if (skb_is_gso(skb)) { |
| 778 | goto append; |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 779 | } |
Kostya B | be9164e | 2008-04-29 22:36:30 -0700 | [diff] [blame] | 780 | |
Jiri Pirko | e93b7d7 | 2013-10-19 12:29:17 +0200 | [diff] [blame] | 781 | skb->ip_summed = CHECKSUM_PARTIAL; |
| 782 | /* specify the length of each IP datagram fragment */ |
| 783 | skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; |
| 784 | skb_shinfo(skb)->gso_type = SKB_GSO_UDP; |
| 785 | |
| 786 | append: |
Kostya B | be9164e | 2008-04-29 22:36:30 -0700 | [diff] [blame] | 787 | return skb_append_datato_frags(sk, skb, getfrag, from, |
| 788 | (length - transhdrlen)); |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 789 | } |
| 790 | |
David S. Miller | f5fca60 | 2011-05-08 17:24:10 -0700 | [diff] [blame] | 791 | static int __ip_append_data(struct sock *sk, |
| 792 | struct flowi4 *fl4, |
| 793 | struct sk_buff_head *queue, |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 794 | struct inet_cork *cork, |
Eric Dumazet | 5640f76 | 2012-09-23 23:04:42 +0000 | [diff] [blame] | 795 | struct page_frag *pfrag, |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 796 | int getfrag(void *from, char *to, int offset, |
| 797 | int len, int odd, struct sk_buff *skb), |
| 798 | void *from, int length, int transhdrlen, |
| 799 | unsigned int flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 800 | { |
| 801 | struct inet_sock *inet = inet_sk(sk); |
| 802 | struct sk_buff *skb; |
| 803 | |
Herbert Xu | 07df529 | 2011-03-01 23:00:58 -0800 | [diff] [blame] | 804 | struct ip_options *opt = cork->opt; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 805 | int hh_len; |
| 806 | int exthdrlen; |
| 807 | int mtu; |
| 808 | int copy; |
| 809 | int err; |
| 810 | int offset = 0; |
Hannes Frederic Sowa | daba287 | 2013-10-27 17:29:11 +0100 | [diff] [blame] | 811 | unsigned int maxfraglen, fragheaderlen, maxnonfragsize; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 812 | int csummode = CHECKSUM_NONE; |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 813 | struct rtable *rt = (struct rtable *)cork->dst; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 814 | |
Steffen Klassert | 96d7303 | 2011-06-05 20:48:47 +0000 | [diff] [blame] | 815 | skb = skb_peek_tail(queue); |
| 816 | |
| 817 | exthdrlen = !skb ? rt->dst.header_len : 0; |
Herbert Xu | 07df529 | 2011-03-01 23:00:58 -0800 | [diff] [blame] | 818 | mtu = cork->fragsize; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 819 | |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 820 | hh_len = LL_RESERVED_SPACE(rt->dst.dev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 821 | |
| 822 | fragheaderlen = sizeof(struct iphdr) + (opt ? opt->optlen : 0); |
| 823 | maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen; |
Hannes Frederic Sowa | 1b34657 | 2014-02-26 01:20:42 +0100 | [diff] [blame] | 824 | maxnonfragsize = ip_sk_local_df(sk) ? 0xFFFF : mtu; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 825 | |
Hannes Frederic Sowa | daba287 | 2013-10-27 17:29:11 +0100 | [diff] [blame] | 826 | if (cork->length + length > maxnonfragsize - fragheaderlen) { |
David S. Miller | f5fca60 | 2011-05-08 17:24:10 -0700 | [diff] [blame] | 827 | ip_local_error(sk, EMSGSIZE, fl4->daddr, inet->inet_dport, |
Hannes Frederic Sowa | 61e7f09 | 2013-12-19 02:13:36 +0100 | [diff] [blame] | 828 | mtu - (opt ? opt->optlen : 0)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 829 | return -EMSGSIZE; |
| 830 | } |
| 831 | |
| 832 | /* |
| 833 | * transhdrlen > 0 means that this is the first fragment and we wish |
| 834 | * it won't be fragmented in the future. |
| 835 | */ |
| 836 | if (transhdrlen && |
| 837 | length + fragheaderlen <= mtu && |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 838 | rt->dst.dev->features & NETIF_F_V4_CSUM && |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 839 | !exthdrlen) |
Patrick McHardy | 84fa793 | 2006-08-29 16:44:56 -0700 | [diff] [blame] | 840 | csummode = CHECKSUM_PARTIAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 841 | |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 842 | cork->length += length; |
Herbert Xu | 26cde9f | 2010-06-15 01:52:25 +0000 | [diff] [blame] | 843 | if (((length > mtu) || (skb && skb_is_gso(skb))) && |
Kostya B | be9164e | 2008-04-29 22:36:30 -0700 | [diff] [blame] | 844 | (sk->sk_protocol == IPPROTO_UDP) && |
Steffen Klassert | c146066 | 2011-06-29 23:19:32 +0000 | [diff] [blame] | 845 | (rt->dst.dev->features & NETIF_F_UFO) && !rt->dst.header_len) { |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 846 | err = ip_ufo_append_data(sk, queue, getfrag, from, length, |
| 847 | hh_len, fragheaderlen, transhdrlen, |
Bill Sommerfeld | d9be4f7 | 2011-07-19 15:22:33 +0000 | [diff] [blame] | 848 | maxfraglen, flags); |
Patrick McHardy | baa829d | 2006-03-12 20:35:12 -0800 | [diff] [blame] | 849 | if (err) |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 850 | goto error; |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 851 | return 0; |
| 852 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 853 | |
| 854 | /* So, what's going on in the loop below? |
| 855 | * |
| 856 | * We use calculated fragment length to generate chained skb, |
| 857 | * each of segments is IP fragment ready for sending to network after |
| 858 | * adding appropriate IP header. |
| 859 | */ |
| 860 | |
Herbert Xu | 26cde9f | 2010-06-15 01:52:25 +0000 | [diff] [blame] | 861 | if (!skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 862 | goto alloc_new_skb; |
| 863 | |
| 864 | while (length > 0) { |
| 865 | /* Check if the remaining data fits into current packet. */ |
| 866 | copy = mtu - skb->len; |
| 867 | if (copy < length) |
| 868 | copy = maxfraglen - skb->len; |
| 869 | if (copy <= 0) { |
| 870 | char *data; |
| 871 | unsigned int datalen; |
| 872 | unsigned int fraglen; |
| 873 | unsigned int fraggap; |
| 874 | unsigned int alloclen; |
| 875 | struct sk_buff *skb_prev; |
| 876 | alloc_new_skb: |
| 877 | skb_prev = skb; |
| 878 | if (skb_prev) |
| 879 | fraggap = skb_prev->len - maxfraglen; |
| 880 | else |
| 881 | fraggap = 0; |
| 882 | |
| 883 | /* |
| 884 | * If remaining data exceeds the mtu, |
| 885 | * we know we need more fragment(s). |
| 886 | */ |
| 887 | datalen = length + fraggap; |
| 888 | if (datalen > mtu - fragheaderlen) |
| 889 | datalen = maxfraglen - fragheaderlen; |
| 890 | fraglen = datalen + fragheaderlen; |
| 891 | |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 892 | if ((flags & MSG_MORE) && |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 893 | !(rt->dst.dev->features&NETIF_F_SG)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 894 | alloclen = mtu; |
| 895 | else |
Eric Dumazet | 59104f0 | 2010-09-20 20:16:27 +0000 | [diff] [blame] | 896 | alloclen = fraglen; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 897 | |
Steffen Klassert | 353e5c9 | 2011-06-22 01:05:37 +0000 | [diff] [blame] | 898 | alloclen += exthdrlen; |
| 899 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 900 | /* The last fragment gets additional space at tail. |
| 901 | * Note, with MSG_MORE we overallocate on fragments, |
| 902 | * because we have no idea what fragment will be |
| 903 | * the last. |
| 904 | */ |
Steffen Klassert | 33f99dc | 2011-06-22 01:04:37 +0000 | [diff] [blame] | 905 | if (datalen == length + fraggap) |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 906 | alloclen += rt->dst.trailer_len; |
Steffen Klassert | 33f99dc | 2011-06-22 01:04:37 +0000 | [diff] [blame] | 907 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 908 | if (transhdrlen) { |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 909 | skb = sock_alloc_send_skb(sk, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 910 | alloclen + hh_len + 15, |
| 911 | (flags & MSG_DONTWAIT), &err); |
| 912 | } else { |
| 913 | skb = NULL; |
| 914 | if (atomic_read(&sk->sk_wmem_alloc) <= |
| 915 | 2 * sk->sk_sndbuf) |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 916 | skb = sock_wmalloc(sk, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 917 | alloclen + hh_len + 15, 1, |
| 918 | sk->sk_allocation); |
| 919 | if (unlikely(skb == NULL)) |
| 920 | err = -ENOBUFS; |
Patrick Ohly | 51f31ca | 2009-02-12 05:03:39 +0000 | [diff] [blame] | 921 | else |
| 922 | /* only the initial fragment is |
| 923 | time stamped */ |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 924 | cork->tx_flags = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 925 | } |
| 926 | if (skb == NULL) |
| 927 | goto error; |
| 928 | |
| 929 | /* |
| 930 | * Fill in the control structures |
| 931 | */ |
| 932 | skb->ip_summed = csummode; |
| 933 | skb->csum = 0; |
| 934 | skb_reserve(skb, hh_len); |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 935 | skb_shinfo(skb)->tx_flags = cork->tx_flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 936 | |
| 937 | /* |
| 938 | * Find where to start putting bytes. |
| 939 | */ |
Steffen Klassert | 353e5c9 | 2011-06-22 01:05:37 +0000 | [diff] [blame] | 940 | data = skb_put(skb, fraglen + exthdrlen); |
Arnaldo Carvalho de Melo | c14d245 | 2007-03-11 22:39:41 -0300 | [diff] [blame] | 941 | skb_set_network_header(skb, exthdrlen); |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 942 | skb->transport_header = (skb->network_header + |
| 943 | fragheaderlen); |
Steffen Klassert | 353e5c9 | 2011-06-22 01:05:37 +0000 | [diff] [blame] | 944 | data += fragheaderlen + exthdrlen; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 945 | |
| 946 | if (fraggap) { |
| 947 | skb->csum = skb_copy_and_csum_bits( |
| 948 | skb_prev, maxfraglen, |
| 949 | data + transhdrlen, fraggap, 0); |
| 950 | skb_prev->csum = csum_sub(skb_prev->csum, |
| 951 | skb->csum); |
| 952 | data += fraggap; |
Herbert Xu | e9fa4f7 | 2006-08-13 20:12:58 -0700 | [diff] [blame] | 953 | pskb_trim_unique(skb_prev, maxfraglen); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 954 | } |
| 955 | |
| 956 | copy = datalen - transhdrlen - fraggap; |
| 957 | if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) { |
| 958 | err = -EFAULT; |
| 959 | kfree_skb(skb); |
| 960 | goto error; |
| 961 | } |
| 962 | |
| 963 | offset += copy; |
| 964 | length -= datalen - fraggap; |
| 965 | transhdrlen = 0; |
| 966 | exthdrlen = 0; |
| 967 | csummode = CHECKSUM_NONE; |
| 968 | |
| 969 | /* |
| 970 | * Put the packet on the pending queue. |
| 971 | */ |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 972 | __skb_queue_tail(queue, skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 973 | continue; |
| 974 | } |
| 975 | |
| 976 | if (copy > length) |
| 977 | copy = length; |
| 978 | |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 979 | if (!(rt->dst.dev->features&NETIF_F_SG)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 980 | unsigned int off; |
| 981 | |
| 982 | off = skb->len; |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 983 | if (getfrag(from, skb_put(skb, copy), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 984 | offset, copy, off, skb) < 0) { |
| 985 | __skb_trim(skb, off); |
| 986 | err = -EFAULT; |
| 987 | goto error; |
| 988 | } |
| 989 | } else { |
| 990 | int i = skb_shinfo(skb)->nr_frags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 991 | |
Eric Dumazet | 5640f76 | 2012-09-23 23:04:42 +0000 | [diff] [blame] | 992 | err = -ENOMEM; |
| 993 | if (!sk_page_frag_refill(sk, pfrag)) |
| 994 | goto error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 995 | |
Eric Dumazet | 5640f76 | 2012-09-23 23:04:42 +0000 | [diff] [blame] | 996 | if (!skb_can_coalesce(skb, i, pfrag->page, |
| 997 | pfrag->offset)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 998 | err = -EMSGSIZE; |
Eric Dumazet | 5640f76 | 2012-09-23 23:04:42 +0000 | [diff] [blame] | 999 | if (i == MAX_SKB_FRAGS) |
| 1000 | goto error; |
| 1001 | |
| 1002 | __skb_fill_page_desc(skb, i, pfrag->page, |
| 1003 | pfrag->offset, 0); |
| 1004 | skb_shinfo(skb)->nr_frags = ++i; |
| 1005 | get_page(pfrag->page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1006 | } |
Eric Dumazet | 5640f76 | 2012-09-23 23:04:42 +0000 | [diff] [blame] | 1007 | copy = min_t(int, copy, pfrag->size - pfrag->offset); |
| 1008 | if (getfrag(from, |
| 1009 | page_address(pfrag->page) + pfrag->offset, |
| 1010 | offset, copy, skb->len, skb) < 0) |
| 1011 | goto error_efault; |
| 1012 | |
| 1013 | pfrag->offset += copy; |
| 1014 | skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1015 | skb->len += copy; |
| 1016 | skb->data_len += copy; |
Herbert Xu | f945fa7 | 2008-01-22 22:39:26 -0800 | [diff] [blame] | 1017 | skb->truesize += copy; |
| 1018 | atomic_add(copy, &sk->sk_wmem_alloc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1019 | } |
| 1020 | offset += copy; |
| 1021 | length -= copy; |
| 1022 | } |
| 1023 | |
| 1024 | return 0; |
| 1025 | |
Eric Dumazet | 5640f76 | 2012-09-23 23:04:42 +0000 | [diff] [blame] | 1026 | error_efault: |
| 1027 | err = -EFAULT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1028 | error: |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1029 | cork->length -= length; |
Pavel Emelyanov | 5e38e27 | 2008-07-16 20:19:49 -0700 | [diff] [blame] | 1030 | IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTDISCARDS); |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 1031 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1032 | } |
| 1033 | |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1034 | static int ip_setup_cork(struct sock *sk, struct inet_cork *cork, |
| 1035 | struct ipcm_cookie *ipc, struct rtable **rtp) |
| 1036 | { |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 1037 | struct ip_options_rcu *opt; |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1038 | struct rtable *rt; |
| 1039 | |
| 1040 | /* |
| 1041 | * setup for corking. |
| 1042 | */ |
| 1043 | opt = ipc->opt; |
| 1044 | if (opt) { |
| 1045 | if (cork->opt == NULL) { |
| 1046 | cork->opt = kmalloc(sizeof(struct ip_options) + 40, |
| 1047 | sk->sk_allocation); |
| 1048 | if (unlikely(cork->opt == NULL)) |
| 1049 | return -ENOBUFS; |
| 1050 | } |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 1051 | memcpy(cork->opt, &opt->opt, sizeof(struct ip_options) + opt->opt.optlen); |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1052 | cork->flags |= IPCORK_OPT; |
| 1053 | cork->addr = ipc->addr; |
| 1054 | } |
| 1055 | rt = *rtp; |
| 1056 | if (unlikely(!rt)) |
| 1057 | return -EFAULT; |
| 1058 | /* |
| 1059 | * We steal reference to this route, caller should not release it |
| 1060 | */ |
| 1061 | *rtp = NULL; |
Hannes Frederic Sowa | 482fc60 | 2013-11-05 02:24:17 +0100 | [diff] [blame] | 1062 | cork->fragsize = ip_sk_use_pmtu(sk) ? |
| 1063 | dst_mtu(&rt->dst) : rt->dst.dev->mtu; |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1064 | cork->dst = &rt->dst; |
| 1065 | cork->length = 0; |
Francesco Fusco | aa66158 | 2013-09-24 15:43:09 +0200 | [diff] [blame] | 1066 | cork->ttl = ipc->ttl; |
| 1067 | cork->tos = ipc->tos; |
| 1068 | cork->priority = ipc->priority; |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1069 | cork->tx_flags = ipc->tx_flags; |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1070 | |
| 1071 | return 0; |
| 1072 | } |
| 1073 | |
| 1074 | /* |
| 1075 | * ip_append_data() and ip_append_page() can make one large IP datagram |
| 1076 | * from many pieces of data. Each pieces will be holded on the socket |
| 1077 | * until ip_push_pending_frames() is called. Each piece can be a page |
| 1078 | * or non-page data. |
| 1079 | * |
| 1080 | * Not only UDP, other transport protocols - e.g. raw sockets - can use |
| 1081 | * this interface potentially. |
| 1082 | * |
| 1083 | * LATER: length must be adjusted by pad at tail, when it is required. |
| 1084 | */ |
David S. Miller | f5fca60 | 2011-05-08 17:24:10 -0700 | [diff] [blame] | 1085 | int ip_append_data(struct sock *sk, struct flowi4 *fl4, |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1086 | int getfrag(void *from, char *to, int offset, int len, |
| 1087 | int odd, struct sk_buff *skb), |
| 1088 | void *from, int length, int transhdrlen, |
| 1089 | struct ipcm_cookie *ipc, struct rtable **rtp, |
| 1090 | unsigned int flags) |
| 1091 | { |
| 1092 | struct inet_sock *inet = inet_sk(sk); |
| 1093 | int err; |
| 1094 | |
| 1095 | if (flags&MSG_PROBE) |
| 1096 | return 0; |
| 1097 | |
| 1098 | if (skb_queue_empty(&sk->sk_write_queue)) { |
David S. Miller | bdc712b | 2011-05-06 15:02:07 -0700 | [diff] [blame] | 1099 | err = ip_setup_cork(sk, &inet->cork.base, ipc, rtp); |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1100 | if (err) |
| 1101 | return err; |
| 1102 | } else { |
| 1103 | transhdrlen = 0; |
| 1104 | } |
| 1105 | |
Eric Dumazet | 5640f76 | 2012-09-23 23:04:42 +0000 | [diff] [blame] | 1106 | return __ip_append_data(sk, fl4, &sk->sk_write_queue, &inet->cork.base, |
| 1107 | sk_page_frag(sk), getfrag, |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1108 | from, length, transhdrlen, flags); |
| 1109 | } |
| 1110 | |
David S. Miller | f5fca60 | 2011-05-08 17:24:10 -0700 | [diff] [blame] | 1111 | ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1112 | int offset, size_t size, int flags) |
| 1113 | { |
| 1114 | struct inet_sock *inet = inet_sk(sk); |
| 1115 | struct sk_buff *skb; |
| 1116 | struct rtable *rt; |
| 1117 | struct ip_options *opt = NULL; |
David S. Miller | bdc712b | 2011-05-06 15:02:07 -0700 | [diff] [blame] | 1118 | struct inet_cork *cork; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1119 | int hh_len; |
| 1120 | int mtu; |
| 1121 | int len; |
| 1122 | int err; |
Hannes Frederic Sowa | daba287 | 2013-10-27 17:29:11 +0100 | [diff] [blame] | 1123 | unsigned int maxfraglen, fragheaderlen, fraggap, maxnonfragsize; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1124 | |
| 1125 | if (inet->hdrincl) |
| 1126 | return -EPERM; |
| 1127 | |
| 1128 | if (flags&MSG_PROBE) |
| 1129 | return 0; |
| 1130 | |
| 1131 | if (skb_queue_empty(&sk->sk_write_queue)) |
| 1132 | return -EINVAL; |
| 1133 | |
David S. Miller | bdc712b | 2011-05-06 15:02:07 -0700 | [diff] [blame] | 1134 | cork = &inet->cork.base; |
| 1135 | rt = (struct rtable *)cork->dst; |
| 1136 | if (cork->flags & IPCORK_OPT) |
| 1137 | opt = cork->opt; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1138 | |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 1139 | if (!(rt->dst.dev->features&NETIF_F_SG)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1140 | return -EOPNOTSUPP; |
| 1141 | |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 1142 | hh_len = LL_RESERVED_SPACE(rt->dst.dev); |
David S. Miller | bdc712b | 2011-05-06 15:02:07 -0700 | [diff] [blame] | 1143 | mtu = cork->fragsize; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1144 | |
| 1145 | fragheaderlen = sizeof(struct iphdr) + (opt ? opt->optlen : 0); |
| 1146 | maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen; |
Hannes Frederic Sowa | 1b34657 | 2014-02-26 01:20:42 +0100 | [diff] [blame] | 1147 | maxnonfragsize = ip_sk_local_df(sk) ? 0xFFFF : mtu; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1148 | |
Hannes Frederic Sowa | daba287 | 2013-10-27 17:29:11 +0100 | [diff] [blame] | 1149 | if (cork->length + size > maxnonfragsize - fragheaderlen) { |
Hannes Frederic Sowa | 61e7f09 | 2013-12-19 02:13:36 +0100 | [diff] [blame] | 1150 | ip_local_error(sk, EMSGSIZE, fl4->daddr, inet->inet_dport, |
| 1151 | mtu - (opt ? opt->optlen : 0)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1152 | return -EMSGSIZE; |
| 1153 | } |
| 1154 | |
| 1155 | if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) |
| 1156 | return -EINVAL; |
| 1157 | |
David S. Miller | bdc712b | 2011-05-06 15:02:07 -0700 | [diff] [blame] | 1158 | cork->length += size; |
Herbert Xu | 26cde9f | 2010-06-15 01:52:25 +0000 | [diff] [blame] | 1159 | if ((size + skb->len > mtu) && |
| 1160 | (sk->sk_protocol == IPPROTO_UDP) && |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 1161 | (rt->dst.dev->features & NETIF_F_UFO)) { |
Herbert Xu | 7967168 | 2006-06-22 02:40:14 -0700 | [diff] [blame] | 1162 | skb_shinfo(skb)->gso_size = mtu - fragheaderlen; |
Herbert Xu | f83ef8c | 2006-06-30 13:37:03 -0700 | [diff] [blame] | 1163 | skb_shinfo(skb)->gso_type = SKB_GSO_UDP; |
Herbert Xu | 7967168 | 2006-06-22 02:40:14 -0700 | [diff] [blame] | 1164 | } |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 1165 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1166 | |
| 1167 | while (size > 0) { |
| 1168 | int i; |
| 1169 | |
Herbert Xu | 89114af | 2006-07-08 13:34:32 -0700 | [diff] [blame] | 1170 | if (skb_is_gso(skb)) |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 1171 | len = size; |
| 1172 | else { |
| 1173 | |
| 1174 | /* Check if the remaining data fits into current packet. */ |
| 1175 | len = mtu - skb->len; |
| 1176 | if (len < size) |
| 1177 | len = maxfraglen - skb->len; |
| 1178 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1179 | if (len <= 0) { |
| 1180 | struct sk_buff *skb_prev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1181 | int alloclen; |
| 1182 | |
| 1183 | skb_prev = skb; |
Jayachandran C | 0d0d2bb | 2005-10-13 11:43:02 -0700 | [diff] [blame] | 1184 | fraggap = skb_prev->len - maxfraglen; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1185 | |
| 1186 | alloclen = fragheaderlen + hh_len + fraggap + 15; |
| 1187 | skb = sock_wmalloc(sk, alloclen, 1, sk->sk_allocation); |
| 1188 | if (unlikely(!skb)) { |
| 1189 | err = -ENOBUFS; |
| 1190 | goto error; |
| 1191 | } |
| 1192 | |
| 1193 | /* |
| 1194 | * Fill in the control structures |
| 1195 | */ |
| 1196 | skb->ip_summed = CHECKSUM_NONE; |
| 1197 | skb->csum = 0; |
| 1198 | skb_reserve(skb, hh_len); |
| 1199 | |
| 1200 | /* |
| 1201 | * Find where to start putting bytes. |
| 1202 | */ |
Arnaldo Carvalho de Melo | 967b05f | 2007-03-13 13:51:52 -0300 | [diff] [blame] | 1203 | skb_put(skb, fragheaderlen + fraggap); |
Arnaldo Carvalho de Melo | 2ca9e6f | 2007-03-10 19:15:25 -0300 | [diff] [blame] | 1204 | skb_reset_network_header(skb); |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 1205 | skb->transport_header = (skb->network_header + |
| 1206 | fragheaderlen); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1207 | if (fraggap) { |
Arnaldo Carvalho de Melo | 967b05f | 2007-03-13 13:51:52 -0300 | [diff] [blame] | 1208 | skb->csum = skb_copy_and_csum_bits(skb_prev, |
| 1209 | maxfraglen, |
Arnaldo Carvalho de Melo | 9c70220 | 2007-04-25 18:04:18 -0700 | [diff] [blame] | 1210 | skb_transport_header(skb), |
Arnaldo Carvalho de Melo | 967b05f | 2007-03-13 13:51:52 -0300 | [diff] [blame] | 1211 | fraggap, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1212 | skb_prev->csum = csum_sub(skb_prev->csum, |
| 1213 | skb->csum); |
Herbert Xu | e9fa4f7 | 2006-08-13 20:12:58 -0700 | [diff] [blame] | 1214 | pskb_trim_unique(skb_prev, maxfraglen); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1215 | } |
| 1216 | |
| 1217 | /* |
| 1218 | * Put the packet on the pending queue. |
| 1219 | */ |
| 1220 | __skb_queue_tail(&sk->sk_write_queue, skb); |
| 1221 | continue; |
| 1222 | } |
| 1223 | |
| 1224 | i = skb_shinfo(skb)->nr_frags; |
| 1225 | if (len > size) |
| 1226 | len = size; |
| 1227 | if (skb_can_coalesce(skb, i, page, offset)) { |
Eric Dumazet | 9e903e0 | 2011-10-18 21:00:24 +0000 | [diff] [blame] | 1228 | skb_frag_size_add(&skb_shinfo(skb)->frags[i-1], len); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1229 | } else if (i < MAX_SKB_FRAGS) { |
| 1230 | get_page(page); |
| 1231 | skb_fill_page_desc(skb, i, page, offset, len); |
| 1232 | } else { |
| 1233 | err = -EMSGSIZE; |
| 1234 | goto error; |
| 1235 | } |
| 1236 | |
| 1237 | if (skb->ip_summed == CHECKSUM_NONE) { |
Al Viro | 44bb936 | 2006-11-14 21:36:14 -0800 | [diff] [blame] | 1238 | __wsum csum; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1239 | csum = csum_page(page, offset, len); |
| 1240 | skb->csum = csum_block_add(skb->csum, csum, skb->len); |
| 1241 | } |
| 1242 | |
| 1243 | skb->len += len; |
| 1244 | skb->data_len += len; |
David S. Miller | 1e34a11 | 2008-01-22 23:44:31 -0800 | [diff] [blame] | 1245 | skb->truesize += len; |
| 1246 | atomic_add(len, &sk->sk_wmem_alloc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1247 | offset += len; |
| 1248 | size -= len; |
| 1249 | } |
| 1250 | return 0; |
| 1251 | |
| 1252 | error: |
David S. Miller | bdc712b | 2011-05-06 15:02:07 -0700 | [diff] [blame] | 1253 | cork->length -= size; |
Pavel Emelyanov | 5e38e27 | 2008-07-16 20:19:49 -0700 | [diff] [blame] | 1254 | IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTDISCARDS); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1255 | return err; |
| 1256 | } |
| 1257 | |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1258 | static void ip_cork_release(struct inet_cork *cork) |
Pavel Emelyanov | 429f08e | 2007-11-05 21:03:24 -0800 | [diff] [blame] | 1259 | { |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1260 | cork->flags &= ~IPCORK_OPT; |
| 1261 | kfree(cork->opt); |
| 1262 | cork->opt = NULL; |
| 1263 | dst_release(cork->dst); |
| 1264 | cork->dst = NULL; |
Pavel Emelyanov | 429f08e | 2007-11-05 21:03:24 -0800 | [diff] [blame] | 1265 | } |
| 1266 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1267 | /* |
| 1268 | * Combined all pending IP fragments on the socket as one IP datagram |
| 1269 | * and push them out. |
| 1270 | */ |
Herbert Xu | 1c32c5a | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1271 | struct sk_buff *__ip_make_skb(struct sock *sk, |
David S. Miller | 77968b7 | 2011-05-08 17:12:19 -0700 | [diff] [blame] | 1272 | struct flowi4 *fl4, |
Herbert Xu | 1c32c5a | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1273 | struct sk_buff_head *queue, |
| 1274 | struct inet_cork *cork) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1275 | { |
| 1276 | struct sk_buff *skb, *tmp_skb; |
| 1277 | struct sk_buff **tail_skb; |
| 1278 | struct inet_sock *inet = inet_sk(sk); |
Pavel Emelyanov | 0388b00 | 2008-07-14 23:00:43 -0700 | [diff] [blame] | 1279 | struct net *net = sock_net(sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1280 | struct ip_options *opt = NULL; |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1281 | struct rtable *rt = (struct rtable *)cork->dst; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1282 | struct iphdr *iph; |
Alexey Dobriyan | 76ab608 | 2006-01-06 13:24:29 -0800 | [diff] [blame] | 1283 | __be16 df = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1284 | __u8 ttl; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1285 | |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1286 | if ((skb = __skb_dequeue(queue)) == NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1287 | goto out; |
| 1288 | tail_skb = &(skb_shinfo(skb)->frag_list); |
| 1289 | |
| 1290 | /* move skb->data to ip header from ext header */ |
Arnaldo Carvalho de Melo | d56f90a | 2007-04-10 20:50:43 -0700 | [diff] [blame] | 1291 | if (skb->data < skb_network_header(skb)) |
Arnaldo Carvalho de Melo | bbe735e | 2007-03-10 22:16:10 -0300 | [diff] [blame] | 1292 | __skb_pull(skb, skb_network_offset(skb)); |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1293 | while ((tmp_skb = __skb_dequeue(queue)) != NULL) { |
Arnaldo Carvalho de Melo | cfe1fc7 | 2007-03-16 17:26:39 -0300 | [diff] [blame] | 1294 | __skb_pull(tmp_skb, skb_network_header_len(skb)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1295 | *tail_skb = tmp_skb; |
| 1296 | tail_skb = &(tmp_skb->next); |
| 1297 | skb->len += tmp_skb->len; |
| 1298 | skb->data_len += tmp_skb->len; |
| 1299 | skb->truesize += tmp_skb->truesize; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1300 | tmp_skb->destructor = NULL; |
| 1301 | tmp_skb->sk = NULL; |
| 1302 | } |
| 1303 | |
| 1304 | /* Unless user demanded real pmtu discovery (IP_PMTUDISC_DO), we allow |
| 1305 | * to fragment the frame generated here. No matter, what transforms |
| 1306 | * how transforms change size of the packet, it will come out. |
| 1307 | */ |
Hannes Frederic Sowa | 1b34657 | 2014-02-26 01:20:42 +0100 | [diff] [blame] | 1308 | skb->local_df = ip_sk_local_df(sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1309 | |
| 1310 | /* DF bit is set when we want to see DF on outgoing frames. |
| 1311 | * If local_df is set too, we still allow to fragment this frame |
| 1312 | * locally. */ |
Hannes Frederic Sowa | 482fc60 | 2013-11-05 02:24:17 +0100 | [diff] [blame] | 1313 | if (inet->pmtudisc == IP_PMTUDISC_DO || |
| 1314 | inet->pmtudisc == IP_PMTUDISC_PROBE || |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 1315 | (skb->len <= dst_mtu(&rt->dst) && |
| 1316 | ip_dont_fragment(sk, &rt->dst))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1317 | df = htons(IP_DF); |
| 1318 | |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1319 | if (cork->flags & IPCORK_OPT) |
| 1320 | opt = cork->opt; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1321 | |
Francesco Fusco | aa66158 | 2013-09-24 15:43:09 +0200 | [diff] [blame] | 1322 | if (cork->ttl != 0) |
| 1323 | ttl = cork->ttl; |
| 1324 | else if (rt->rt_type == RTN_MULTICAST) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1325 | ttl = inet->mc_ttl; |
| 1326 | else |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 1327 | ttl = ip_select_ttl(inet, &rt->dst); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1328 | |
Ansis Atteka | 749154a | 2013-09-18 15:29:52 -0700 | [diff] [blame] | 1329 | iph = ip_hdr(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1330 | iph->version = 4; |
| 1331 | iph->ihl = 5; |
Francesco Fusco | aa66158 | 2013-09-24 15:43:09 +0200 | [diff] [blame] | 1332 | iph->tos = (cork->tos != -1) ? cork->tos : inet->tos; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1333 | iph->frag_off = df; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1334 | iph->ttl = ttl; |
| 1335 | iph->protocol = sk->sk_protocol; |
Eric Dumazet | 84f9307 | 2011-11-30 19:00:53 +0000 | [diff] [blame] | 1336 | ip_copy_addrs(iph, fl4); |
Ansis Atteka | 703133d | 2013-09-18 15:29:53 -0700 | [diff] [blame] | 1337 | ip_select_ident(skb, &rt->dst, sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1338 | |
David S. Miller | 22f728f | 2011-05-13 17:21:27 -0400 | [diff] [blame] | 1339 | if (opt) { |
| 1340 | iph->ihl += opt->optlen>>2; |
| 1341 | ip_options_build(skb, opt, cork->addr, rt, 0); |
| 1342 | } |
| 1343 | |
Francesco Fusco | aa66158 | 2013-09-24 15:43:09 +0200 | [diff] [blame] | 1344 | skb->priority = (cork->tos != -1) ? cork->priority: sk->sk_priority; |
Laszlo Attila Toth | 4a19ec5 | 2008-01-30 19:08:16 -0800 | [diff] [blame] | 1345 | skb->mark = sk->sk_mark; |
Eric Dumazet | a21bba9 | 2008-11-24 16:07:50 -0800 | [diff] [blame] | 1346 | /* |
| 1347 | * Steal rt from cork.dst to avoid a pair of atomic_inc/atomic_dec |
| 1348 | * on dst refcount |
| 1349 | */ |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1350 | cork->dst = NULL; |
Changli Gao | d8d1f30 | 2010-06-10 23:31:35 -0700 | [diff] [blame] | 1351 | skb_dst_set(skb, &rt->dst); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1352 | |
David L Stevens | 96793b4 | 2007-09-17 09:57:33 -0700 | [diff] [blame] | 1353 | if (iph->protocol == IPPROTO_ICMP) |
Pavel Emelyanov | 0388b00 | 2008-07-14 23:00:43 -0700 | [diff] [blame] | 1354 | icmp_out_count(net, ((struct icmphdr *) |
David L Stevens | 96793b4 | 2007-09-17 09:57:33 -0700 | [diff] [blame] | 1355 | skb_transport_header(skb))->type); |
| 1356 | |
Herbert Xu | 1c32c5a | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1357 | ip_cork_release(cork); |
| 1358 | out: |
| 1359 | return skb; |
| 1360 | } |
| 1361 | |
Eric Dumazet | b5ec8ee | 2012-08-10 02:22:47 +0000 | [diff] [blame] | 1362 | int ip_send_skb(struct net *net, struct sk_buff *skb) |
Herbert Xu | 1c32c5a | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1363 | { |
Herbert Xu | 1c32c5a | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1364 | int err; |
| 1365 | |
Herbert Xu | c439cb2 | 2008-01-11 19:14:00 -0800 | [diff] [blame] | 1366 | err = ip_local_out(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1367 | if (err) { |
| 1368 | if (err > 0) |
Eric Dumazet | 6ce9e7b | 2009-09-02 18:05:33 -0700 | [diff] [blame] | 1369 | err = net_xmit_errno(err); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1370 | if (err) |
Herbert Xu | 1c32c5a | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1371 | IP_INC_STATS(net, IPSTATS_MIB_OUTDISCARDS); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1372 | } |
| 1373 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1374 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1375 | } |
| 1376 | |
David S. Miller | 77968b7 | 2011-05-08 17:12:19 -0700 | [diff] [blame] | 1377 | int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4) |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1378 | { |
Herbert Xu | 1c32c5a | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1379 | struct sk_buff *skb; |
| 1380 | |
David S. Miller | 77968b7 | 2011-05-08 17:12:19 -0700 | [diff] [blame] | 1381 | skb = ip_finish_skb(sk, fl4); |
Herbert Xu | 1c32c5a | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1382 | if (!skb) |
| 1383 | return 0; |
| 1384 | |
| 1385 | /* Netfilter gets whole the not fragmented skb. */ |
Eric Dumazet | b5ec8ee | 2012-08-10 02:22:47 +0000 | [diff] [blame] | 1386 | return ip_send_skb(sock_net(sk), skb); |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1387 | } |
| 1388 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1389 | /* |
| 1390 | * Throw away all pending data on the socket. |
| 1391 | */ |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1392 | static void __ip_flush_pending_frames(struct sock *sk, |
| 1393 | struct sk_buff_head *queue, |
| 1394 | struct inet_cork *cork) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1395 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1396 | struct sk_buff *skb; |
| 1397 | |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1398 | while ((skb = __skb_dequeue_tail(queue)) != NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1399 | kfree_skb(skb); |
| 1400 | |
Herbert Xu | 1470ddf | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1401 | ip_cork_release(cork); |
| 1402 | } |
| 1403 | |
| 1404 | void ip_flush_pending_frames(struct sock *sk) |
| 1405 | { |
David S. Miller | bdc712b | 2011-05-06 15:02:07 -0700 | [diff] [blame] | 1406 | __ip_flush_pending_frames(sk, &sk->sk_write_queue, &inet_sk(sk)->cork.base); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1407 | } |
| 1408 | |
Herbert Xu | 1c32c5a | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1409 | struct sk_buff *ip_make_skb(struct sock *sk, |
David S. Miller | 77968b7 | 2011-05-08 17:12:19 -0700 | [diff] [blame] | 1410 | struct flowi4 *fl4, |
Herbert Xu | 1c32c5a | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1411 | int getfrag(void *from, char *to, int offset, |
| 1412 | int len, int odd, struct sk_buff *skb), |
| 1413 | void *from, int length, int transhdrlen, |
| 1414 | struct ipcm_cookie *ipc, struct rtable **rtp, |
| 1415 | unsigned int flags) |
| 1416 | { |
David S. Miller | b80d722 | 2011-05-06 15:06:01 -0700 | [diff] [blame] | 1417 | struct inet_cork cork; |
Herbert Xu | 1c32c5a | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1418 | struct sk_buff_head queue; |
| 1419 | int err; |
| 1420 | |
| 1421 | if (flags & MSG_PROBE) |
| 1422 | return NULL; |
| 1423 | |
| 1424 | __skb_queue_head_init(&queue); |
| 1425 | |
David S. Miller | b80d722 | 2011-05-06 15:06:01 -0700 | [diff] [blame] | 1426 | cork.flags = 0; |
| 1427 | cork.addr = 0; |
David S. Miller | 7065272 | 2011-05-06 16:01:15 -0700 | [diff] [blame] | 1428 | cork.opt = NULL; |
Herbert Xu | 1c32c5a | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1429 | err = ip_setup_cork(sk, &cork, ipc, rtp); |
| 1430 | if (err) |
| 1431 | return ERR_PTR(err); |
| 1432 | |
Eric Dumazet | 5640f76 | 2012-09-23 23:04:42 +0000 | [diff] [blame] | 1433 | err = __ip_append_data(sk, fl4, &queue, &cork, |
| 1434 | ¤t->task_frag, getfrag, |
Herbert Xu | 1c32c5a | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1435 | from, length, transhdrlen, flags); |
| 1436 | if (err) { |
| 1437 | __ip_flush_pending_frames(sk, &queue, &cork); |
| 1438 | return ERR_PTR(err); |
| 1439 | } |
| 1440 | |
David S. Miller | 77968b7 | 2011-05-08 17:12:19 -0700 | [diff] [blame] | 1441 | return __ip_make_skb(sk, fl4, &queue, &cork); |
Herbert Xu | 1c32c5a | 2011-03-01 02:36:47 +0000 | [diff] [blame] | 1442 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1443 | |
| 1444 | /* |
| 1445 | * Fetch data from kernel space and fill in checksum if needed. |
| 1446 | */ |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 1447 | static int ip_reply_glue_bits(void *dptr, char *to, int offset, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1448 | int len, int odd, struct sk_buff *skb) |
| 1449 | { |
Al Viro | 5084205 | 2006-11-14 21:36:34 -0800 | [diff] [blame] | 1450 | __wsum csum; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1451 | |
| 1452 | csum = csum_partial_copy_nocheck(dptr+offset, to, len, 0); |
| 1453 | skb->csum = csum_block_add(skb->csum, csum, odd); |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 1454 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1455 | } |
| 1456 | |
YOSHIFUJI Hideaki | e905a9e | 2007-02-09 23:24:47 +0900 | [diff] [blame] | 1457 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1458 | * Generic function to send a packet as reply to another packet. |
Eric Dumazet | be9f4a4 | 2012-07-19 07:34:03 +0000 | [diff] [blame] | 1459 | * Used to send some TCP resets/acks so far. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1460 | * |
Eric Dumazet | be9f4a4 | 2012-07-19 07:34:03 +0000 | [diff] [blame] | 1461 | * Use a fake percpu inet socket to avoid false sharing and contention. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1462 | */ |
Eric Dumazet | be9f4a4 | 2012-07-19 07:34:03 +0000 | [diff] [blame] | 1463 | static DEFINE_PER_CPU(struct inet_sock, unicast_sock) = { |
| 1464 | .sk = { |
| 1465 | .__sk_common = { |
| 1466 | .skc_refcnt = ATOMIC_INIT(1), |
| 1467 | }, |
| 1468 | .sk_wmem_alloc = ATOMIC_INIT(1), |
| 1469 | .sk_allocation = GFP_ATOMIC, |
| 1470 | .sk_flags = (1UL << SOCK_USE_WRITE_QUEUE), |
| 1471 | }, |
Eric Dumazet | 0980e56 | 2012-07-20 22:28:51 +0000 | [diff] [blame] | 1472 | .pmtudisc = IP_PMTUDISC_WANT, |
| 1473 | .uc_ttl = -1, |
Eric Dumazet | be9f4a4 | 2012-07-19 07:34:03 +0000 | [diff] [blame] | 1474 | }; |
| 1475 | |
| 1476 | void ip_send_unicast_reply(struct net *net, struct sk_buff *skb, __be32 daddr, |
David S. Miller | 70e7341 | 2012-06-28 03:21:41 -0700 | [diff] [blame] | 1477 | __be32 saddr, const struct ip_reply_arg *arg, |
| 1478 | unsigned int len) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1479 | { |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 1480 | struct ip_options_data replyopts; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1481 | struct ipcm_cookie ipc; |
David S. Miller | 77968b7 | 2011-05-08 17:12:19 -0700 | [diff] [blame] | 1482 | struct flowi4 fl4; |
Eric Dumazet | 511c3f9 | 2009-06-02 05:14:27 +0000 | [diff] [blame] | 1483 | struct rtable *rt = skb_rtable(skb); |
Eric Dumazet | be9f4a4 | 2012-07-19 07:34:03 +0000 | [diff] [blame] | 1484 | struct sk_buff *nskb; |
| 1485 | struct sock *sk; |
| 1486 | struct inet_sock *inet; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1487 | |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 1488 | if (ip_options_echo(&replyopts.opt.opt, skb)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1489 | return; |
| 1490 | |
David S. Miller | 0a5ebb8 | 2011-05-09 13:22:43 -0700 | [diff] [blame] | 1491 | ipc.addr = daddr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1492 | ipc.opt = NULL; |
Oliver Hartkopp | 2244d07 | 2010-08-17 08:59:14 +0000 | [diff] [blame] | 1493 | ipc.tx_flags = 0; |
Francesco Fusco | aa66158 | 2013-09-24 15:43:09 +0200 | [diff] [blame] | 1494 | ipc.ttl = 0; |
| 1495 | ipc.tos = -1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1496 | |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 1497 | if (replyopts.opt.opt.optlen) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1498 | ipc.opt = &replyopts.opt; |
| 1499 | |
Eric Dumazet | f6d8bd0 | 2011-04-21 09:45:37 +0000 | [diff] [blame] | 1500 | if (replyopts.opt.opt.srr) |
| 1501 | daddr = replyopts.opt.opt.faddr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1502 | } |
| 1503 | |
David S. Miller | 77968b7 | 2011-05-08 17:12:19 -0700 | [diff] [blame] | 1504 | flowi4_init_output(&fl4, arg->bound_dev_if, 0, |
Eric Dumazet | 66b13d9 | 2011-10-24 03:06:21 -0400 | [diff] [blame] | 1505 | RT_TOS(arg->tos), |
Eric Dumazet | be9f4a4 | 2012-07-19 07:34:03 +0000 | [diff] [blame] | 1506 | RT_SCOPE_UNIVERSE, ip_hdr(skb)->protocol, |
David S. Miller | 77968b7 | 2011-05-08 17:12:19 -0700 | [diff] [blame] | 1507 | ip_reply_arg_flowi_flags(arg), |
David S. Miller | 70e7341 | 2012-06-28 03:21:41 -0700 | [diff] [blame] | 1508 | daddr, saddr, |
David S. Miller | 77968b7 | 2011-05-08 17:12:19 -0700 | [diff] [blame] | 1509 | tcp_hdr(skb)->source, tcp_hdr(skb)->dest); |
| 1510 | security_skb_classify_flow(skb, flowi4_to_flowi(&fl4)); |
Eric Dumazet | be9f4a4 | 2012-07-19 07:34:03 +0000 | [diff] [blame] | 1511 | rt = ip_route_output_key(net, &fl4); |
David S. Miller | 77968b7 | 2011-05-08 17:12:19 -0700 | [diff] [blame] | 1512 | if (IS_ERR(rt)) |
| 1513 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1514 | |
Eric Dumazet | be9f4a4 | 2012-07-19 07:34:03 +0000 | [diff] [blame] | 1515 | inet = &get_cpu_var(unicast_sock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1516 | |
Eric Dumazet | 66b13d9 | 2011-10-24 03:06:21 -0400 | [diff] [blame] | 1517 | inet->tos = arg->tos; |
Eric Dumazet | be9f4a4 | 2012-07-19 07:34:03 +0000 | [diff] [blame] | 1518 | sk = &inet->sk; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1519 | sk->sk_priority = skb->priority; |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 1520 | sk->sk_protocol = ip_hdr(skb)->protocol; |
Patrick McHardy | f0e48db | 2007-06-04 21:32:46 -0700 | [diff] [blame] | 1521 | sk->sk_bound_dev_if = arg->bound_dev_if; |
Eric Dumazet | be9f4a4 | 2012-07-19 07:34:03 +0000 | [diff] [blame] | 1522 | sock_net_set(sk, net); |
| 1523 | __skb_queue_head_init(&sk->sk_write_queue); |
| 1524 | sk->sk_sndbuf = sysctl_wmem_default; |
David S. Miller | f5fca60 | 2011-05-08 17:24:10 -0700 | [diff] [blame] | 1525 | ip_append_data(sk, &fl4, ip_reply_glue_bits, arg->iov->iov_base, len, 0, |
Eric Dumazet | 2e77d89 | 2008-11-24 15:52:46 -0800 | [diff] [blame] | 1526 | &ipc, &rt, MSG_DONTWAIT); |
Eric Dumazet | be9f4a4 | 2012-07-19 07:34:03 +0000 | [diff] [blame] | 1527 | nskb = skb_peek(&sk->sk_write_queue); |
| 1528 | if (nskb) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1529 | if (arg->csumoffset >= 0) |
Eric Dumazet | be9f4a4 | 2012-07-19 07:34:03 +0000 | [diff] [blame] | 1530 | *((__sum16 *)skb_transport_header(nskb) + |
| 1531 | arg->csumoffset) = csum_fold(csum_add(nskb->csum, |
Arnaldo Carvalho de Melo | 9c70220 | 2007-04-25 18:04:18 -0700 | [diff] [blame] | 1532 | arg->csum)); |
Eric Dumazet | be9f4a4 | 2012-07-19 07:34:03 +0000 | [diff] [blame] | 1533 | nskb->ip_summed = CHECKSUM_NONE; |
Eric Dumazet | 3a7c384 | 2012-08-09 13:56:06 +0000 | [diff] [blame] | 1534 | skb_orphan(nskb); |
Eric Dumazet | be9f4a4 | 2012-07-19 07:34:03 +0000 | [diff] [blame] | 1535 | skb_set_queue_mapping(nskb, skb_get_queue_mapping(skb)); |
David S. Miller | 77968b7 | 2011-05-08 17:12:19 -0700 | [diff] [blame] | 1536 | ip_push_pending_frames(sk, &fl4); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1537 | } |
| 1538 | |
Eric Dumazet | be9f4a4 | 2012-07-19 07:34:03 +0000 | [diff] [blame] | 1539 | put_cpu_var(unicast_sock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1540 | |
| 1541 | ip_rt_put(rt); |
| 1542 | } |
| 1543 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1544 | void __init ip_init(void) |
| 1545 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1546 | ip_rt_init(); |
| 1547 | inet_initpeers(); |
| 1548 | |
WANG Cong | 72c1d3b | 2014-01-10 16:09:45 -0800 | [diff] [blame] | 1549 | #if defined(CONFIG_IP_MULTICAST) |
| 1550 | igmp_mc_init(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1551 | #endif |
| 1552 | } |