cregit-Linux how code gets into the kernel

Release 4.8 net/ipv4/ip_output.c

Directory: net/ipv4
/*
 * INET         An implementation of the TCP/IP protocol suite for the LINUX
 *              operating system.  INET is implemented using the  BSD Socket
 *              interface as the means of communication with the user level.
 *
 *              The Internet Protocol (IP) output module.
 *
 * Authors:     Ross Biro
 *              Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *              Donald Becker, <becker@super.org>
 *              Alan Cox, <Alan.Cox@linux.org>
 *              Richard Underwood
 *              Stefan Becker, <stefanb@yello.ping.de>
 *              Jorge Cwik, <jorge@laser.satlink.net>
 *              Arnt Gulbrandsen, <agulbra@nvg.unit.no>
 *              Hirokazu Takahashi, <taka@valinux.co.jp>
 *
 *      See ip_input.c for original log
 *
 *      Fixes:
 *              Alan Cox        :       Missing nonblock feature in ip_build_xmit.
 *              Mike Kilburn    :       htons() missing in ip_build_xmit.
 *              Bradford Johnson:       Fix faulty handling of some frames when
 *                                      no route is found.
 *              Alexander Demenshin:    Missing sk/skb free in ip_queue_xmit
 *                                      (in case if packet not accepted by
 *                                      output firewall rules)
 *              Mike McLagan    :       Routing by source
 *              Alexey Kuznetsov:       use new route cache
 *              Andi Kleen:             Fix broken PMTU recovery and remove
 *                                      some redundant tests.
 *      Vitaly E. Lavrov        :       Transparent proxy revived after year coma.
 *              Andi Kleen      :       Replace ip_reply with ip_send_reply.
 *              Andi Kleen      :       Split fast and slow ip_build_xmit path
 *                                      for decreased register pressure on x86
 *                                      and more readibility.
 *              Marc Boucher    :       When call_out_firewall returns FW_QUEUE,
 *                                      silently drop skb instead of failing with -EPERM.
 *              Detlev Wengorz  :       Copy protocol for fragments.
 *              Hirokazu Takahashi:     HW checksumming for outgoing UDP
 *                                      datagrams.
 *              Hirokazu Takahashi:     sendfile() on UDP works now.
 */

#include <asm/uaccess.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/highmem.h>
#include <linux/slab.h>

#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/in.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/proc_fs.h>
#include <linux/stat.h>
#include <linux/init.h>

#include <net/snmp.h>
#include <net/ip.h>
#include <net/protocol.h>
#include <net/route.h>
#include <net/xfrm.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <net/arp.h>
#include <net/icmp.h>
#include <net/checksum.h>
#include <net/inetpeer.h>
#include <linux/igmp.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter_bridge.h>
#include <linux/netlink.h>
#include <linux/tcp.h>

static int
ip_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
	    unsigned int mtu,
	    int (*output)(struct net *, struct sock *, struct sk_buff *));

/* Generate a checksum for an outgoing IP datagram. */

void ip_send_check(struct iphdr *iph) { iph->check = 0; iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl); }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git34100.00%1100.00%
Total34100.00%1100.00%

EXPORT_SYMBOL(ip_send_check);
int __ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb) { struct iphdr *iph = ip_hdr(skb); iph->tot_len = htons(skb->len); ip_send_check(iph); return nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT, net, sk, skb, NULL, skb_dst(skb)->dev, dst_output); }

Contributors

PersonTokensPropCommitsCommitProp
herbert xuherbert xu4766.20%111.11%
david s. millerdavid s. miller1014.08%111.11%
eric w. biedermaneric w. biederman912.68%444.44%
eric dumazeteric dumazet34.23%111.11%
jan engelhardtjan engelhardt11.41%111.11%
patrick mchardypatrick mchardy11.41%111.11%
Total71100.00%9100.00%


int ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb) { int err; err = __ip_local_out(net, sk, skb); if (likely(err == 1)) err = dst_output(net, sk, skb); return err; }

Contributors

PersonTokensPropCommitsCommitProp
herbert xuherbert xu3663.16%111.11%
eric w. biedermaneric w. biederman1424.56%777.78%
eric dumazeteric dumazet712.28%111.11%
Total57100.00%9100.00%

EXPORT_SYMBOL_GPL(ip_local_out);
static inline int ip_select_ttl(struct inet_sock *inet, struct dst_entry *dst) { int ttl = inet->uc_ttl; if (ttl < 0) ttl = ip4_dst_hoplimit(dst); return ttl; }

Contributors

PersonTokensPropCommitsCommitProp
david s. millerdavid s. miller3997.50%266.67%
arnaldo carvalho de meloarnaldo carvalho de melo12.50%133.33%
Total40100.00%3100.00%

/* * Add an ip header to a skbuff and send it out. * */
int ip_build_and_send_pkt(struct sk_buff *skb, const struct sock *sk, __be32 saddr, __be32 daddr, struct ip_options_rcu *opt) { struct inet_sock *inet = inet_sk(sk); struct rtable *rt = skb_rtable(skb); struct net *net = sock_net(sk); struct iphdr *iph; /* Build the IP header. */ skb_push(skb, sizeof(struct iphdr) + (opt ? opt->opt.optlen : 0)); skb_reset_network_header(skb); iph = ip_hdr(skb); iph->version = 4; iph->ihl = 5; iph->tos = inet->tos; iph->ttl = ip_select_ttl(inet, &rt->dst); iph->daddr = (opt && opt->opt.srr ? opt->opt.faddr : daddr); iph->saddr = saddr; iph->protocol = sk->sk_protocol; if (ip_dont_fragment(sk, &rt->dst)) { iph->frag_off = htons(IP_DF); iph->id = 0; } else { iph->frag_off = 0; __ip_select_ident(net, iph, 1); } if (opt && opt->opt.optlen) { iph->ihl += opt->opt.optlen>>2; ip_options_build(skb, &opt->opt, daddr, rt, 0); } skb->priority = sk->sk_priority; skb->mark = sk->sk_mark; /* Send it out. */ return ip_local_out(net, skb->sk, skb); }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git14149.65%1035.71%
eric dumazeteric dumazet5519.37%310.71%
david s. millerdavid s. miller3512.32%310.71%
arnaldo carvalho de meloarnaldo carvalho de melo175.99%414.29%
eric w. biedermaneric w. biederman175.99%310.71%
laszlo attila tothlaszlo attila toth82.82%13.57%
alexey kuznetsovalexey kuznetsov72.46%13.57%
al viroal viro20.70%13.57%
hannes frederic sowahannes frederic sowa10.35%13.57%
herbert xuherbert xu10.35%13.57%
Total284100.00%28100.00%

EXPORT_SYMBOL_GPL(ip_build_and_send_pkt);
static int ip_finish_output2(struct net *net, struct sock *sk, struct sk_buff *skb) { struct dst_entry *dst = skb_dst(skb); struct rtable *rt = (struct rtable *)dst; struct net_device *dev = dst->dev; unsigned int hh_len = LL_RESERVED_SPACE(dev); struct neighbour *neigh; u32 nexthop; if (rt->rt_type == RTN_MULTICAST) { IP_UPD_PO_STATS(net, IPSTATS_MIB_OUTMCAST, skb->len); } else if (rt->rt_type == RTN_BROADCAST) IP_UPD_PO_STATS(net, IPSTATS_MIB_OUTBCAST, skb->len); /* Be paranoid, rather than too clever. */ if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) { struct sk_buff *skb2; skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev)); if (!skb2) { kfree_skb(skb); return -ENOMEM; } if (skb->sk) skb_set_owner_w(skb2, skb->sk); consume_skb(skb); skb = skb2; } rcu_read_lock_bh(); nexthop = (__force u32) rt_nexthop(rt, ip_hdr(skb)->daddr); neigh = __ipv4_neigh_lookup_noref(dev, nexthop); if (unlikely(!neigh)) neigh = __neigh_create(&arp_tbl, &nexthop, dev, false); if (!IS_ERR(neigh)) { int res = dst_neigh_output(dst, neigh, skb); rcu_read_unlock_bh(); return res; } rcu_read_unlock_bh(); net_dbg_ratelimited("%s: No header cache and no neighbour!\n", __func__); kfree_skb(skb); return -EINVAL; }

Contributors

PersonTokensPropCommitsCommitProp
alexey kuznetsovalexey kuznetsov8931.12%27.69%
david s. millerdavid s. miller6522.73%726.92%
pre-gitpre-git3712.94%311.54%
mitsuru chinenmitsuru chinen3512.24%13.85%
eric dumazeteric dumazet186.29%311.54%
neil hormanneil horman144.90%13.85%
julian anastasovjulian anastasov82.80%13.85%
eric w. biedermaneric w. biederman72.45%27.69%
joe perchesjoe perches41.40%13.85%
vasiliy kulikovvasiliy kulikov41.40%13.85%
pavel emelianovpavel emelianov20.70%13.85%
stephen hemmingerstephen hemminger10.35%13.85%
ian morrisian morris10.35%13.85%
chuck leverchuck lever10.35%13.85%
Total286100.00%26100.00%


static int ip_finish_output_gso(struct net *net, struct sock *sk, struct sk_buff *skb, unsigned int mtu) { netdev_features_t features; struct sk_buff *segs; int ret = 0; /* common case: fragmentation of segments is not allowed, * or seglen is <= mtu */ if (((IPCB(skb)->flags & IPSKB_FRAG_SEGS) == 0) || skb_gso_validate_mtu(skb, mtu)) return ip_finish_output2(net, sk, skb); /* Slowpath - GSO segment length is exceeding the dst MTU. * * This can happen in two cases: * 1) TCP GRO packet, DF bit not set * 2) skb arrived via virtio-net, we thus get TSO/GSO skbs directly * from host network stack. */ features = netif_skb_features(skb); BUILD_BUG_ON(sizeof(*IPCB(skb)) > SKB_SGO_CB_OFFSET); segs = skb_gso_segment(skb, features & ~NETIF_F_GSO_MASK); if (IS_ERR_OR_NULL(segs)) { kfree_skb(skb); return -ENOMEM; } consume_skb(skb); do { struct sk_buff *nskb = segs->next; int err; segs->next = NULL; err = ip_fragment(net, sk, segs, mtu, ip_finish_output2); if (err && ret == 0) ret = err; segs = nskb; } while (segs); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
florian westphalflorian westphal15380.53%337.50%
konstantin khlebnikovkonstantin khlebnikov147.37%112.50%
eric w. biedermaneric w. biederman94.74%112.50%
david s. millerdavid s. miller94.74%112.50%
marcelo ricardo leitnermarcelo ricardo leitner31.58%112.50%
shmulik ladkanishmulik ladkani21.05%112.50%
Total190100.00%8100.00%


static int ip_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb) { unsigned int mtu; #if defined(CONFIG_NETFILTER) && defined(CONFIG_XFRM) /* Policy lookup after SNAT yielded a new policy */ if (skb_dst(skb)->xfrm) { IPCB(skb)->flags |= IPSKB_REROUTED; return dst_output(net, sk, skb); } #endif mtu = ip_skb_dst_mtu(sk, skb); if (skb_is_gso(skb)) return ip_finish_output_gso(net, sk, skb, mtu); if (skb->len > mtu || (IPCB(skb)->flags & IPSKB_FRAG_PMTU)) return ip_fragment(net, sk, skb, mtu, ip_finish_output2); return ip_finish_output2(net, sk, skb); }

Contributors

PersonTokensPropCommitsCommitProp
patrick mchardypatrick mchardy4834.29%318.75%
florian westphalflorian westphal4028.57%318.75%
pre-gitpre-git1913.57%212.50%
eric w. biedermaneric w. biederman1410.00%425.00%
david s. millerdavid s. miller139.29%16.25%
eric dumazeteric dumazet32.14%16.25%
shmulik ladkanishmulik ladkani21.43%16.25%
adrian bunkadrian bunk10.71%16.25%
Total140100.00%16100.00%


int ip_mc_output(struct net *net, struct sock *sk, struct sk_buff *skb) { struct rtable *rt = skb_rtable(skb); struct net_device *dev = rt->dst.dev; /* * If the indicated interface is up and running, send the packet. */ IP_UPD_PO_STATS(net, IPSTATS_MIB_OUT, skb->len); skb->dev = dev; skb->protocol = htons(ETH_P_IP); /* * Multicasts are looped back for other local users */ if (rt->rt_flags&RTCF_MULTICAST) { if (sk_mc_loop(sk) #ifdef CONFIG_IP_MROUTE /* Small optimization: do not loopback not local frames, which returned after forwarding; they will be dropped by ip_mr_input in any case. Note, that local frames are looped back to be delivered to local recipients. This check is duplicated in ip_mr_input at the moment. */ && ((rt->rt_flags & RTCF_LOCAL) || !(IPCB(skb)->flags & IPSKB_FORWARDED)) #endif ) { struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC); if (newskb) NF_HOOK(NFPROTO_IPV4, NF_INET_POST_ROUTING, net, sk, newskb, NULL, newskb->dev, dev_loopback_xmit); } /* Multicasts with ttl 0 must not go beyond the host */ if (ip_hdr(skb)->ttl == 0) { kfree_skb(skb); return 0; } } if (rt->rt_flags&RTCF_BROADCAST) { struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC); if (newskb) NF_HOOK(NFPROTO_IPV4, NF_INET_POST_ROUTING, net, sk, newskb, NULL, newskb->dev, dev_loopback_xmit); } return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING, net, sk, skb, NULL, skb->dev, ip_finish_output, !(IPCB(skb)->flags & IPSKB_REROUTED)); }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git17267.19%931.03%
patrick mchardypatrick mchardy249.38%310.34%
eric w. biedermaneric w. biederman155.86%310.34%
eric dumazeteric dumazet83.12%26.90%
linus torvaldslinus torvalds83.12%13.45%
david s. millerdavid s. miller83.12%26.90%
neil hormanneil horman51.95%13.45%
alexey kuznetsovalexey kuznetsov41.56%13.45%
arnaldo carvalho de meloarnaldo carvalho de melo31.17%13.45%
jan engelhardtjan engelhardt31.17%13.45%
michel machadomichel machado20.78%13.45%
hideaki yoshifujihideaki yoshifuji10.39%13.45%
octavian purdilaoctavian purdila10.39%13.45%
herbert xuherbert xu10.39%13.45%
pavel emelianovpavel emelianov10.39%13.45%
Total256100.00%29100.00%


int ip_output(struct net *net, struct sock *sk, struct sk_buff *skb) { struct net_device *dev = skb_dst(skb)->dev; IP_UPD_PO_STATS(net, IPSTATS_MIB_OUT, skb->len); skb->dev = dev; skb->protocol = htons(ETH_P_IP); return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING, net, sk, skb, NULL, dev, ip_finish_output, !(IPCB(skb)->flags & IPSKB_REROUTED)); }

Contributors

PersonTokensPropCommitsCommitProp
patrick mchardypatrick mchardy3842.22%316.67%
pre-gitpre-git1516.67%316.67%
eric w. biedermaneric w. biederman1011.11%316.67%
eric dumazeteric dumazet88.89%211.11%
alexey kuznetsovalexey kuznetsov77.78%15.56%
neil hormanneil horman55.56%15.56%
ananda rajuananda raju22.22%15.56%
david s. millerdavid s. miller22.22%15.56%
herbert xuherbert xu11.11%15.56%
pavel emelianovpavel emelianov11.11%15.56%
jan engelhardtjan engelhardt11.11%15.56%
Total90100.00%18100.00%

/* * copy saddr and daddr, possibly using 64bit load/stores * Equivalent to : * iph->saddr = fl4->saddr; * iph->daddr = fl4->daddr; */
static void ip_copy_addrs(struct iphdr *iph, const struct flowi4 *fl4) { BUILD_BUG_ON(offsetof(typeof(*fl4), daddr) != offsetof(typeof(*fl4), saddr) + sizeof(fl4->saddr)); memcpy(&iph->saddr, &fl4->saddr, sizeof(fl4->saddr) + sizeof(fl4->daddr)); }

Contributors

PersonTokensPropCommitsCommitProp
eric dumazeteric dumazet76100.00%1100.00%
Total76100.00%1100.00%

/* Note: skb->sk can be different from sk, in case of tunnels */
int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl) { struct inet_sock *inet = inet_sk(sk); struct net *net = sock_net(sk); struct ip_options_rcu *inet_opt; struct flowi4 *fl4; struct rtable *rt; struct iphdr *iph; int res; /* Skip all of this if the packet is already routed, * f.e. by something like SCTP. */ rcu_read_lock(); inet_opt = rcu_dereference(inet->inet_opt); fl4 = &fl->u.ip4; rt = skb_rtable(skb); if (rt) goto packet_routed; /* Make sure we can route this packet. */ rt = (struct rtable *)__sk_dst_check(sk, 0); if (!rt) { __be32 daddr; /* Use correct destination address if we have options. */ daddr = inet->inet_daddr; if (inet_opt && inet_opt->opt.srr) daddr = inet_opt->opt.faddr; /* If this fails, retransmit mechanism of transport layer will * keep trying until route appears or the connection times * itself out. */ rt = ip_route_output_ports(net, fl4, sk, daddr, inet->inet_saddr, inet->inet_dport, inet->inet_sport, sk->sk_protocol, RT_CONN_FLAGS(sk), sk->sk_bound_dev_if); if (IS_ERR(rt)) goto no_route; sk_setup_caps(sk, &rt->dst); } skb_dst_set_noref(skb, &rt->dst); packet_routed: if (inet_opt && inet_opt->opt.is_strictroute && rt->rt_uses_gateway) goto no_route; /* OK, we know where to send it, allocate and build IP header. */ skb_push(skb, sizeof(struct iphdr) + (inet_opt ? inet_opt->opt.optlen : 0)); skb_reset_network_header(skb); iph = ip_hdr(skb); *((__be16 *)iph) = htons((4 << 12) | (5 << 8) | (inet->tos & 0xff)); if (ip_dont_fragment(sk, &rt->dst) && !skb->ignore_df) iph->frag_off = htons(IP_DF); else iph->frag_off = 0; iph->ttl = ip_select_ttl(inet, &rt->dst); iph->protocol = sk->sk_protocol; ip_copy_addrs(iph, fl4); /* Transport layer set skb->h.foo itself. */ if (inet_opt && inet_opt->opt.optlen) { iph->ihl += inet_opt->opt.optlen >> 2; ip_options_build(skb, &inet_opt->opt, inet->inet_daddr, rt, 0); } ip_select_ident_segs(net, skb, sk, skb_shinfo(skb)->gso_segs ?: 1); /* TODO : should we use skb->sk here instead of sk ? */ skb->priority = sk->sk_priority; skb->mark = sk->sk_mark; res = ip_local_out(net, sk, skb); rcu_read_unlock(); return res; no_route: rcu_read_unlock(); IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES); kfree_skb(skb); return -EHOSTUNREACH; }

Contributors

PersonTokensPropCommitsCommitProp
alexey kuznetsovalexey kuznetsov21243.80%35.45%
eric dumazeteric dumazet7315.08%814.55%
pre-gitpre-git7114.67%59.09%
david s. millerdavid s. miller6112.60%1018.18%
eric w. biedermaneric w. biederman183.72%47.27%
arnaldo carvalho de meloarnaldo carvalho de melo163.31%59.09%
laszlo attila tothlaszlo attila toth81.65%11.82%
herbert xuherbert xu40.83%23.64%
hideaki yoshifujihideaki yoshifuji30.62%23.64%
al viroal viro20.41%23.64%
denis v. lunevdenis v. lunev20.41%23.64%
venkat yekkiralavenkat yekkirala20.41%11.82%
shan weishan wei20.41%11.82%
sridhar samudralasridhar samudrala20.41%11.82%
pavel emelianovpavel emelianov10.21%11.82%
linus torvaldslinus torvalds10.21%11.82%
americo wangamerico wang10.21%11.82%
julian anastasovjulian anastasov10.21%11.82%
ansis attekaansis atteka10.21%11.82%
ian morrisian morris10.21%11.82%
hannes frederic sowahannes frederic sowa10.21%11.82%
atis elstsatis elsts10.21%11.82%
Total484100.00%55100.00%

EXPORT_SYMBOL(ip_queue_xmit);
static void ip_copy_metadata(struct sk_buff *to, struct sk_buff *from) { to->pkt_type = from->pkt_type; to->priority = from->priority; to->protocol = from->protocol; skb_dst_drop(to); skb_dst_copy(to, from); to->dev = from->dev; to->mark = from->mark; /* Copy the flags to each fragment. */ IPCB(to)->flags = IPCB(from)->flags; #ifdef CONFIG_NET_SCHED to->tc_index = from->tc_index; #endif nf_copy(to, from); #if defined(CONFIG_IP_VS) || defined(CONFIG_IP_VS_MODULE) to->ipvs_property = from->ipvs_property; #endif skb_copy_secmark(to, from); }

Contributors

PersonTokensPropCommitsCommitProp
alexey kuznetsovalexey kuznetsov8262.60%110.00%
julian anastasovjulian anastasov1914.50%110.00%
thomas grafthomas graf86.11%110.00%
james morrisjames morris75.34%110.00%
eric dumazeteric dumazet53.82%220.00%
patrick mchardypatrick mchardy43.05%110.00%
jozsef kadlecsikjozsef kadlecsik43.05%220.00%
yasuyuki kozakaiyasuyuki kozakai21.53%110.00%
Total131100.00%10100.00%


static int ip_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, unsigned int mtu, int (*output)(struct net *, struct sock *, struct sk_buff *)) { struct iphdr *iph = ip_hdr(skb); if ((iph->frag_off & htons(IP_DF)) == 0) return ip_do_fragment(net, sk, skb, output); if (unlikely(!skb->ignore_df || (IPCB(skb)->frag_max_size && IPCB(skb)->frag_max_size > mtu))) { IP_INC_STATS(net, IPSTATS_MIB_FRAGFAILS); icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu)); kfree_skb(skb); return -EMSGSIZE; } return ip_do_fragment(net, sk, skb, output); }

Contributors

PersonTokensPropCommitsCommitProp
alexey kuznetsovalexey kuznetsov6743.79%214.29%
florian westphalflorian westphal2113.73%214.29%
patrick mchardypatrick mchardy1811.76%17.14%
eric w. biedermaneric w. biederman149.15%214.29%
andy zhouandy zhou138.50%17.14%
david s. millerdavid s. miller95.88%17.14%
wei dongwei dong53.27%17.14%
eric dumazeteric dumazet21.31%17.14%
hannes frederic sowahannes frederic sowa21.31%17.14%
americo wangamerico wang10.65%17.14%
pavel emelianovpavel emelianov10.65%17.14%
Total153100.00%14100.00%

/* * This IP datagram is too large to be sent in one piece. Break it up into * smaller pieces (each of size equal to IP header plus * a block of the data of the original IP data part) that will yet fit in a * single device frame, and queue such a frame for sending. */
int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, int (*output)(struct net *, struct sock *, struct sk_buff *)) { struct iphdr *iph; int ptr; struct net_device *dev; struct sk_buff *skb2; unsigned int mtu, hlen, left, len, ll_rs; int offset; __be16 not_last_frag; struct rtable *rt = skb_rtable(skb); int err = 0; dev = rt->dst.dev; /* for offloaded checksums cleanup checksum before fragmentation */ if (skb->ip_summed == CHECKSUM_PARTIAL && (err = skb_checksum_help(skb))) goto fail; /* * Point into the IP datagram header. */ iph = ip_hdr(skb); mtu = ip_skb_dst_mtu(sk, skb); if (IPCB(skb)->frag_max_size && IPCB(skb)->frag_max_size < mtu) mtu = IPCB(skb)->frag_max_size; /* * Setup starting values. */ hlen = iph->ihl * 4; mtu = mtu - hlen; /* Size of data space */ IPCB(skb)->flags |= IPSKB_FRAG_COMPLETE; /* When frag_list is given, use it. First, check its validity: * some transformers could create wrong frag_list or break existing * one, it is not prohibited. In this case fall back to copying. * * LATER: this step can be merged to real generation of fragments, * we can switch to copy when see the first bad fragment. */ if (skb_has_frag_list(skb)) { struct sk_buff *frag, *frag2; int first_len = skb_pagelen(skb); if (first_len - hlen > mtu || ((first_len - hlen) & 7) || ip_is_fragment(iph) || skb_cloned(skb)) goto slow_path; skb_walk_frags(skb, frag) { /* Correct geometry. */ if (frag->len > mtu || ((frag->len & 7) && frag->next) || skb_headroom(frag) < hlen) goto slow_path_clean; /* Partially cloned skb? */ if (skb_shared(frag)) goto slow_path_clean; BUG_ON(frag->sk); if (skb->sk) { frag->sk = skb->sk; frag->destructor = sock_wfree; } skb->truesize -= frag->truesize; } /* Everything is OK. Generate! */ err = 0; offset = 0; frag = skb_shinfo(skb)->frag_list; skb_frag_list_init(skb); skb->data_len = first_len - skb_headlen(skb); skb->len = first_len; iph->tot_len = htons(first_len); iph->frag_off = htons(IP_MF); ip_send_check(iph); for (;;) { /* Prepare header of the next frame, * before previous one went down. */ if (frag) { frag->ip_summed = CHECKSUM_NONE; skb_reset_transport_header(frag); __skb_push(frag, hlen); skb_reset_network_header(frag); memcpy(skb_network_header(frag), iph, hlen); iph = ip_hdr(frag); iph->tot_len = htons(frag->len); ip_copy_metadata(frag, skb); if (offset == 0) ip_options_fragment(frag); offset += skb->len - hlen; iph->frag_off = htons(offset>>3); if (frag->next) iph->frag_off |= htons(IP_MF); /* Ready, complete checksum */ ip_send_check(iph); } err = output(net, sk, skb); if (!err) IP_INC_STATS(net, IPSTATS_MIB_FRAGCREATES); if (err || !frag) break; skb = frag; frag = skb->next; skb->next = NULL; } if (err == 0) { IP_INC_STATS(net, IPSTATS_MIB_FRAGOKS); return 0; } while (frag) { skb = frag->next; kfree_skb(frag); frag = skb; } IP_INC_STATS(net, IPSTATS_MIB_FRAGFAILS); return err; slow_path_clean: skb_walk_frags(skb, frag2) { if (frag2 == frag) break; frag2->sk = NULL; frag2->destructor = NULL; skb->truesize += frag2->truesize; } } slow_path: iph = ip_hdr(skb); left = skb->len - hlen; /* Space per frame */ ptr = hlen; /* Where to start from */ ll_rs = LL_RESERVED_SPACE(rt->dst.dev); /* * Fragment the datagram. */ offset = (ntohs(iph->frag_off) & IP_OFFSET) << 3; not_last_frag = iph->frag_off & htons(IP_MF); /* * Keep copying data until we run out. */ while (left > 0) { len = left; /* IF: it doesn't fit, use 'mtu' - the data space left */ if (len > mtu) len = mtu; /* IF: we are not sending up to and including the packet end then align the next start on an eight byte boundary */ if (len < left) { len &= ~7; } /* Allocate buffer */ skb2 = alloc_skb(len + hlen + ll_rs, GFP_ATOMIC); if (!skb2) { err = -ENOMEM; goto fail; } /* * Set up data on packet */ ip_copy_metadata(skb2, skb); skb_reserve(skb2, ll_rs); skb_put(skb2, len + hlen); skb_reset_network_header(skb2); skb2->transport_header = skb2->network_header + hlen; /* * Charge the memory for the fragment to any owner * it might possess */ if (skb->sk) skb_set_owner_w(skb2, skb->sk); /* * Copy the packet header into the new buffer. */ skb_copy_from_linear_data(skb, skb_network_header(skb2), hlen); /* * Copy a block of the IP datagram. */ if (skb_copy_bits(skb, ptr, skb_transport_header(skb2), len)) BUG(); left -= len; /* * Fill in the new header fields. */ iph = ip_hdr(skb2); iph->frag_off = htons((offset >> 3)); if (IPCB(skb)->flags & IPSKB_FRAG_PMTU) iph->frag_off |= htons(IP_DF); /* ANK: dirty, but effective trick. Upgrade options only if * the segment to be fragmented was THE FIRST (otherwise, * options are already fixed) and make it ONCE * on the initial skb, so that all the following fragments * will inherit fixed options. */ if (offset == 0) ip_options_fragment(skb); /* * Added AC : If we are fragmenting a fragment that's not the * last fragment then keep MF on each bit */ if (left > 0 || not_last_frag) iph->frag_off |= htons(IP_MF); ptr += len; offset += len; /* * Put this fragment into the sending queue. */ iph->tot_len = htons(len + hlen); ip_send_check(iph); err = output(net, sk, skb2); if (err) goto fail; IP_INC_STATS(net, IPSTATS_MIB_FRAGCREATES); } consume_skb(skb); IP_INC_STATS(net, IPSTATS_MIB_FRAGOKS); return err; fail: kfree_skb(skb); IP_INC_STATS(net, IPSTATS_MIB_FRAGFAILS); return err; }

Contributors

PersonTokensPropCommitsCommitProp
alexey kuznetsovalexey kuznetsov64462.65%12.78%
andy zhouandy zhou10310.02%12.78%
florian westphalflorian westphal484.67%25.56%
herbert xuherbert xu484.67%411.11%
eric dumazeteric dumazet474.57%25.56%
arnaldo carvalho de meloarnaldo carvalho de melo313.02%822.22%
hannes frederic sowahannes frederic sowa222.14%25.56%
eric w. biedermaneric w. biederman191.85%25.56%
wei dongwei dong151.46%12.78%
bart de schuymerbart de schuymer111.07%12.78%
david s. millerdavid s. miller100.97%38.33%
pravin b shelarpravin b shelar70.68%12.78%
joe perchesjoe perches60.58%12.78%
pavel emelianovpavel emelianov60.58%12.78%
hideaki yoshifujihideaki yoshifuji40.39%12.78%
shmulik ladkanishmulik ladkani20.19%12.78%
paul gortmakerpaul gortmaker20.19%12.78%
patrick mchardypatrick mchardy10.10%12.78%
stephen hemmingerstephen hemminger10.10%12.78%
lucas de marchilucas de marchi10.10%12.78%
Total1028100.00%36100.00%

EXPORT_SYMBOL(ip_do_fragment);
int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb) { struct msghdr *msg = from; if (skb->ip_summed == CHECKSUM_PARTIAL) { if (copy_from_iter(to, len, &msg->msg_iter) != len) return -EFAULT; } else { __wsum csum = 0; if (csum_and_copy_from_iter(to, len, &csum, &msg->msg_iter) != len) return -EFAULT; skb->csum = csum_block_add(skb->csum, csum, odd); } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
alexey kuznetsovalexey kuznetsov9281.42%228.57%
al viroal viro2017.70%457.14%
patrick mchardypatrick mchardy10.88%114.29%
Total113100.00%7100.00%

EXPORT_SYMBOL(ip_generic_getfrag);
static inline __wsum csum_page(struct page *page, int offset, int copy) { char *kaddr; __wsum csum; kaddr = kmap(page); csum = csum_partial(kaddr + offset, copy, 0); kunmap(page); return csum; }

Contributors

PersonTokensPropCommitsCommitProp
alexey kuznetsovalexey kuznetsov4075.47%111.11%
pre-gitpre-git1120.75%777.78%
al viroal viro23.77%111.11%
Total53100.00%9100.00%


static inline int ip_ufo_append_data(struct sock *sk, struct sk_buff_head *queue, int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb), void *from, int length, int hh_len, int fragheaderlen, int transhdrlen, int maxfraglen, unsigned int flags) { struct sk_buff *skb; int err; /* There is support for UDP fragmentation offload by network * device, so create one single skb packet containing complete * udp datagram */ skb = skb_peek_tail(queue); if (!skb) { skb = sock_alloc_send_skb(sk, hh_len + fragheaderlen + transhdrlen + 20, (flags & MSG_DONTWAIT), &err); if (!skb) return err; /* reserve space for Hardware header */ skb_reserve(skb, hh_len); /* create space for UDP/IP header */ skb_put(skb, fragheaderlen + transhdrlen); /* initialize network header pointer */ skb_reset_network_header(skb); /* initialize protocol header pointer */ skb->transport_header = skb->network_header + fragheaderlen; skb->csum = 0; __skb_queue_tail(queue, skb); } else if (skb_is_gso(skb)) { goto append; } skb->ip_summed = CHECKSUM_PARTIAL; /* specify the length of each IP datagram fragment */ skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; skb_shinfo(skb)->gso_type = SKB_GSO_UDP; append: return skb_append_datato_frags(sk, skb, getfrag, from, (length - transhdrlen)); }

Contributors

PersonTokensPropCommitsCommitProp
ananda rajuananda raju15768.56%19.09%
jiri pirkojiri pirko2711.79%19.09%
herbert xuherbert xu166.99%327.27%
kostya belezkokostya belezko156.55%19.09%
ian morrisian morris62.62%19.09%
arnaldo carvalho de meloarnaldo carvalho de melo52.18%218.18%
bill sommerfeldbill sommerfeld20.87%19.09%
adrian bunkadrian bunk10.44%19.09%
Total229100.00%11100.00%


static int __ip_append_data(struct sock *sk, struct flowi4 *fl4, struct sk_buff_head *queue, struct inet_cork *cork, struct page_frag *pfrag, int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb), void *from, int length, int transhdrlen, unsigned int flags) { struct inet_sock *inet = inet_sk(sk); struct sk_buff *skb; struct ip_options *opt = cork->opt; int hh_len; int exthdrlen; int mtu; int copy; int err; int offset = 0; unsigned int maxfraglen, fragheaderlen, maxnonfragsize; int csummode = CHECKSUM_NONE; struct rtable *rt = (struct rtable *)cork->dst; u32 tskey = 0; skb = skb_peek_tail(queue); exthdrlen = !skb ? rt->dst.header_len : 0; mtu = cork->fragsize; if (cork->tx_flags & SKBTX_ANY_SW_TSTAMP && sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID) tskey = sk->sk_tskey++; hh_len = LL_RESERVED_SPACE(rt->dst.dev); fragheaderlen = sizeof(struct iphdr) + (opt ? opt->optlen : 0); maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen; maxnonfragsize = ip_sk_ignore_df(sk) ? 0xFFFF : mtu; if (cork->length + length > maxnonfragsize - fragheaderlen) { ip_local_error(sk, EMSGSIZE, fl4->daddr, inet->inet_dport, mtu - (opt ? opt->optlen : 0)); return -EMSGSIZE; } /* * transhdrlen > 0 means that this is the first fragment and we wish * it won't be fragmented in the future. */ if (transhdrlen && length + fragheaderlen <= mtu && rt->dst.dev->features & (NETIF_F_HW_CSUM | NETIF_F_IP_CSUM) && !(flags & MSG_MORE) && !exthdrlen) csummode = CHECKSUM_PARTIAL; cork->length += length; if (((length > mtu) || (skb && skb_is_gso(skb))) && (sk->sk_protocol == IPPROTO_UDP) && (rt->dst.dev->features & NETIF_F_UFO) && !rt->dst.header_len && (sk->sk_type == SOCK_DGRAM) && !sk->sk_no_check_tx) { err = ip_ufo_append_data(sk, queue, getfrag, from, length, hh_len, fragheaderlen, transhdrlen, maxfraglen, flags); if (err) goto error; return 0; } /* So, what's going on in the loop below? * * We use calculated fragment length to generate chained skb, * each of segments is IP fragment ready for sending to network after * adding appropriate IP header. */ if (!skb) goto alloc_new_skb; while (length > 0) { /* Check if the remaining data fits into current packet. */ copy = mtu - skb->len; if (copy < length) copy = maxfraglen - skb->len; if (copy <= 0) { char *data; unsigned int datalen; unsigned int fraglen; unsigned int fraggap; unsigned int alloclen; struct sk_buff *skb_prev; alloc_new_skb: skb_prev = skb; if (skb_prev) fraggap = skb_prev->len - maxfraglen; else fraggap = 0; /* * If remaining data exceeds the mtu, * we know we need more fragment(s). */ datalen = length + fraggap; if (datalen > mtu - fragheaderlen) datalen = maxfraglen - fragheaderlen; fraglen = datalen + fragheaderlen; if ((flags & MSG_MORE) && !(rt->dst.dev->features&NETIF_F_SG)) alloclen = mtu; else alloclen = fraglen; alloclen += exthdrlen; /* The last fragment gets additional space at tail. * Note, with MSG_MORE we overallocate on fragments, * because we have no idea what fragment will be * the last. */ if (datalen == length + fraggap) alloclen += rt->dst.trailer_len; if (transhdrlen) { skb = sock_alloc_send_skb(sk, alloclen + hh_len + 15, (flags & MSG_DONTWAIT), &err); } else { skb = NULL; if (atomic_read(&sk->sk_wmem_alloc) <= 2 * sk->sk_sndbuf) skb = sock_wmalloc(sk, alloclen + hh_len + 15, 1, sk->sk_allocation); if (unlikely(!skb)) err = -ENOBUFS; } if (!skb) goto error; /* * Fill in the control structures */ skb->ip_summed = csummode; skb->csum = 0; skb_reserve(skb, hh_len); /* only the initial fragment is time stamped */ skb_shinfo(skb)->tx_flags = cork->tx_flags; cork->tx_flags = 0; skb_shinfo(skb)->tskey = tskey; tskey = 0; /* * Find where to start putting bytes. */ data = skb_put(skb, fraglen + exthdrlen); skb_set_network_header(skb, exthdrlen); skb->transport_header = (skb->network_header + fragheaderlen); data += fragheaderlen + exthdrlen; if (fraggap) { skb->csum = skb_copy_and_csum_bits( skb_prev, maxfraglen, data + transhdrlen, fraggap, 0); skb_prev->csum = csum_sub(skb_prev->csum, skb->csum); data += fraggap; pskb_trim_unique(skb_prev, maxfraglen); } copy = datalen - transhdrlen - fraggap; if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) { err = -EFAULT; kfree_skb(skb); goto error; } offset += copy; length -= datalen - fraggap; transhdrlen = 0; exthdrlen = 0; csummode = CHECKSUM_NONE; /* * Put the packet on the pending queue. */ __skb_queue_tail(queue, skb); continue; } if (copy > length) copy = length; if (!(rt->dst.dev->features&NETIF_F_SG)) { unsigned int off; off = skb->len; if (getfrag(from, skb_put(skb, copy), offset, copy, off, skb) < 0) { __skb_trim(skb, off); err = -EFAULT; goto error; } } else { int i = skb_shinfo(skb)->nr_frags; err = -ENOMEM; if (!sk_page_frag_refill(sk, pfrag)) goto error; if (!skb_can_coalesce(skb, i, pfrag->page, pfrag->offset)) { err = -EMSGSIZE; if (i == MAX_SKB_FRAGS) goto error; __skb_fill_page_desc(skb, i, pfrag->page, pfrag->offset, 0); skb_shinfo(skb)->nr_frags = ++i; get_page(pfrag->page); } copy = min_t(int, copy, pfrag->size - pfrag->offset); if (getfrag(from, page_address(pfrag->page) + pfrag->offset, offset, copy, skb->len, skb) < 0) goto error_efault; pfrag->offset += copy; skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy); skb->len += copy; skb->data_len += copy; skb->truesize += copy; atomic_add(copy, &sk->sk_wmem_alloc); } offset += copy; length -= copy; } return 0; error_efault: err = -EFAULT; error: cork->length -= length; IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTDISCARDS); return err; }

Contributors

PersonTokensPropCommitsCommitProp
herbert xuherbert xu51641.75%610.71%
alexey kuznetsovalexey kuznetsov28523.06%47.14%
pre-gitpre-git1159.30%1119.64%
eric dumazeteric dumazet967.77%47.14%
willem de bruijnwillem de bruijn463.72%23.57%
david s. millerdavid s. miller302.43%47.14%
hannes frederic sowahannes frederic sowa292.35%47.14%
hideaki yoshifujihideaki yoshifuji262.10%23.57%
steffen klassertsteffen klassert241.94%35.36%
michal kubecekmichal kubecek131.05%23.57%
ananda rajuananda raju131.05%11.79%
krishna kumarkrishna kumar100.81%11.79%
john heffnerjohn heffner80.65%11.79%
patrick mchardypatrick mchardy70.57%23.57%
tom herberttom herbert50.40%11.79%
julien tinnesjulien tinnes40.32%11.79%
ian morrisian morris20.16%11.79%
ian campbellian campbell20.16%11.79%
arnaldo carvalho de meloarnaldo carvalho de melo10.08%11.79%
linus torvaldslinus torvalds10.08%11.79%
americo wangamerico wang10.08%11.79%
kostya belezkokostya belezko10.08%11.79%
bill sommerfeldbill sommerfeld10.08%11.79%
Total1236100.00%56100.00%


static int ip_setup_cork(struct sock *sk, struct inet_cork *cork, struct ipcm_cookie *ipc, struct rtable **rtp) { struct ip_options_rcu *opt; struct rtable *rt; /* * setup for corking. */ opt = ipc->opt; if (opt) { if (!cork->opt) { cork->opt = kmalloc(sizeof(struct ip_options) + 40, sk->sk_allocation); if (unlikely(!cork->opt)) return -ENOBUFS; } memcpy(cork->opt, &opt->opt, sizeof(struct ip_options) + opt->opt.optlen); cork->flags |= IPCORK_OPT; cork->addr = ipc->addr; } rt = *rtp; if (unlikely(!rt)) return -EFAULT; /* * We steal reference to this route, caller should not release it */ *rtp = NULL; cork->fragsize = ip_sk_use_pmtu(sk) ? dst_mtu(&rt->dst) : rt->dst.dev->mtu; cork->dst = &rt->dst; cork->length = 0; cork->ttl = ipc->ttl; cork->tos = ipc->tos; cork->priority = ipc->priority; cork->tx_flags = ipc->tx_flags; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
herbert xuherbert xu18380.26%116.67%
francesco fuscofrancesco fusco2410.53%116.67%
hannes frederic sowahannes frederic sowa125.26%116.67%
eric dumazeteric dumazet62.63%116.67%
ian morrisian morris20.88%116.67%
steffen klassertsteffen klassert10.44%116.67%
Total228100.00%6100.00%

/* * ip_append_data() and ip_append_page() can make one large IP datagram * from many pieces of data. Each pieces will be holded on the socket * until ip_push_pending_frames() is called. Each piece can be a page * or non-page data. * * Not only UDP, other transport protocols - e.g. raw sockets - can use * this interface potentially. * * LATER: length must be adjusted by pad at tail, when it is required. */
int ip_append_data(struct sock *sk, struct flowi4 *fl4, int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb), void *from, int length, int transhdrlen, struct ipcm_cookie *ipc, struct rtable **rtp, unsigned int flags) { struct inet_sock *inet = inet_sk(sk); int err; if (flags&MSG_PROBE) return 0; if (skb_queue_empty(&sk->sk_write_queue)) { err = ip_setup_cork(sk, &inet->cork.base, ipc, rtp); if (err) return err; } else { transhdrlen = 0; } return __ip_append_data(sk, fl4, &sk->sk_write_queue, &inet->cork.base, sk_page_frag(sk), getfrag, from, length, transhdrlen, flags); }

Contributors

PersonTokensPropCommitsCommitProp
herbert xuherbert xu13480.24%215.38%
david s. millerdavid s. miller116.59%215.38%
pre-gitpre-git105.99%646.15%
alexey kuznetsovalexey kuznetsov63.59%17.69%
eric dumazeteric dumazet52.99%17.69%
pavel emelianovpavel emelianov10.60%17.69%
Total167100.00%13100.00%


ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page, int offset, size_t size, int flags) { struct inet_sock *inet = inet_sk(sk); struct sk_buff *skb; struct rtable *rt; struct ip_options *opt = NULL; struct inet_cork *cork; int hh_len; int mtu; int len; int err; unsigned int maxfraglen, fragheaderlen, fraggap, maxnonfragsize; if (inet->hdrincl) return -EPERM; if (flags&MSG_PROBE) return 0; if (skb_queue_empty(&sk->sk_write_queue)) return -EINVAL; cork = &inet->cork.base; rt = (struct rtable *)cork->dst; if (cork->flags & IPCORK_OPT) opt = cork->opt; if (!(rt->dst.dev->features&NETIF_F_SG)) return -EOPNOTSUPP; hh_len = LL_RESERVED_SPACE(rt->dst.dev); mtu = cork->fragsize; fragheaderlen = sizeof(struct iphdr) + (opt ? opt->optlen : 0); maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen; maxnonfragsize = ip_sk_ignore_df(sk) ? 0xFFFF : mtu; if (cork->length + size > maxnonfragsize - fragheaderlen) { ip_local_error(sk, EMSGSIZE, fl4->daddr, inet->inet_dport, mtu - (opt ? opt->optlen : 0)); return -EMSGSIZE; } skb = skb_peek_tail(&sk->sk_write_queue); if (!skb) return -EINVAL; if ((size + skb->len > mtu) && (sk->sk_protocol == IPPROTO_UDP) && (rt->dst.dev->features & NETIF_F_UFO)) { if (skb->ip_summed != CHECKSUM_PARTIAL) return -EOPNOTSUPP; skb_shinfo(skb)->gso_size = mtu - fragheaderlen; skb_shinfo(skb)->gso_type = SKB_GSO_UDP; } cork->length += size; while (size > 0) { if (skb_is_gso(skb)) { len = size; } else { /* Check if the remaining data fits into current packet. */ len = mtu - skb->len; if (len < size) len = maxfraglen - skb->len; } if (len <= 0) { struct sk_buff *skb_prev; int alloclen; skb_prev = skb; fraggap = skb_prev->len - maxfraglen; alloclen = fragheaderlen + hh_len + fraggap + 15; skb = sock_wmalloc(sk, alloclen, 1, sk->sk_allocation); if (unlikely(!skb)) { err = -ENOBUFS; goto error; } /* * Fill in the control structures */ skb->ip_summed = CHECKSUM_NONE; skb->csum = 0; skb_reserve(skb, hh_len); /* * Find where to start putting bytes. */ skb_put(skb, fragheaderlen + fraggap); skb_reset_network_header(skb); skb->transport_header = (skb->network_header + fragheaderlen); if (fraggap) { skb->csum = skb_copy_and_csum_bits(skb_prev, maxfraglen, skb_transport_header(skb), fraggap, 0); skb_prev->csum = csum_sub(skb_prev->csum, skb->csum); pskb_trim_unique(skb_prev, maxfraglen); } /* * Put the packet on the pending queue. */ __skb_queue_tail(&sk->sk_write_queue, skb); continue; } if (len > size) len = size; if (skb_append_pagefrags(skb, page, offset, len)) { err = -EMSGSIZE; goto error; } if (skb->ip_summed == CHECKSUM_NONE) { __wsum csum; csum = csum_page(page, offset, len); skb->csum = csum_block_add(skb->csum, csum, skb->len); } skb->len += len; skb->data_len += len; skb->truesize += len; atomic_add(len, &sk->sk_wmem_alloc); offset += len; size -= len; } return 0; error: cork->length -= size; IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTDISCARDS); return err; }

Contributors

PersonTokensPropCommitsCommitProp
alexey kuznetsovalexey kuznetsov25835.59%23.85%
pre-gitpre-git14520.00%1426.92%
david s. millerdavid s. miller10514.48%611.54%
herbert xuherbert xu466.34%713.46%
ananda rajuananda raju456.21%11.92%
hannes frederic sowahannes frederic sowa446.07%59.62%
hideaki yoshifujihideaki yoshifuji283.86%35.77%
arnaldo carvalho de meloarnaldo carvalho de melo223.03%611.54%
patrick mchardypatrick mchardy162.21%11.92%
ian morrisian morris50.69%11.92%
pavel emelianovpavel emelianov50.69%11.92%
eric dumazeteric dumazet30.41%23.85%
al viroal viro10.14%11.92%
americo wangamerico wang10.14%11.92%
linus torvaldslinus torvalds10.14%11.92%
Total725100.00%52100.00%


static void ip_cork_release(struct inet_cork *cork) { cork->flags &= ~IPCORK_OPT; kfree(cork->opt); cork->opt = NULL; dst_release(cork->dst); cork->dst = NULL; }

Contributors

PersonTokensPropCommitsCommitProp
pavel emelianovpavel emelianov3477.27%133.33%
herbert xuherbert xu715.91%133.33%
hideaki yoshifujihideaki yoshifuji36.82%133.33%
Total44100.00%3100.00%

/* * Combined all pending IP fragments on the socket as one IP datagram * and push them out. */
struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4, struct sk_buff_head *queue, struct inet_cork *cork) { struct sk_buff *skb, *tmp_skb; struct sk_buff **tail_skb; struct inet_sock *inet = inet_sk(sk); struct net *net = sock_net(sk); struct ip_options *opt = NULL; struct rtable *rt = (struct rtable *)cork->dst; struct iphdr *iph; __be16 df = 0; __u8 ttl; skb = __skb_dequeue(queue); if (!skb) goto out; tail_skb = &(skb_shinfo(skb)->frag_list); /* move skb->data to ip header from ext header */ if (skb->data < skb_network_header(skb)) __skb_pull(skb, skb_network_offset(skb)); while ((tmp_skb = __skb_dequeue(queue)) != NULL) { __skb_pull(tmp_skb, skb_network_header_len(skb)); *tail_skb = tmp_skb; tail_skb = &(tmp_skb->next); skb->len += tmp_skb->len; skb->data_len += tmp_skb->len; skb->truesize += tmp_skb->truesize; tmp_skb->destructor = NULL; tmp_skb->sk = NULL; } /* Unless user demanded real pmtu discovery (IP_PMTUDISC_DO), we allow * to fragment the frame generated here. No matter, what transforms * how transforms change size of the packet, it will come out. */ skb->ignore_df = ip_sk_ignore_df(sk); /* DF bit is set when we want to see DF on outgoing frames. * If ignore_df is set too, we still allow to fragment this frame * locally. */ if (inet->pmtudisc == IP_PMTUDISC_DO || inet->pmtudisc == IP_PMTUDISC_PROBE || (skb->len <= dst_mtu(&rt->dst) && ip_dont_fragment(sk, &rt->dst))) df = htons(IP_DF); if (cork->flags & IPCORK_OPT) opt = cork->opt; if (cork->ttl != 0) ttl = cork->ttl; else if (rt->rt_type == RTN_MULTICAST) ttl = inet->mc_ttl; else ttl = ip_select_ttl(inet, &rt->dst); iph = ip_hdr(skb); iph->version = 4; iph->ihl = 5; iph->tos = (cork->tos != -1) ? cork->tos : inet->tos; iph->frag_off = df; iph->ttl = ttl; iph->protocol = sk->sk_protocol; ip_copy_addrs(iph, fl4); ip_select_ident(net, skb, sk); if (opt) { iph->ihl += opt->optlen>>2; ip_options_build(skb, opt, cork->addr, rt, 0); } skb->priority = (cork->tos != -1) ? cork->priority: sk->sk_priority; skb->mark = sk->sk_mark; /* * Steal rt from cork.dst to avoid a pair of atomic_inc/atomic_dec * on dst refcount */ cork->dst = NULL; skb_dst_set(skb, &rt->dst); if (iph->protocol == IPPROTO_ICMP) icmp_out_count(net, ((struct icmphdr *) skb_transport_header(skb))->type); ip_cork_release(cork); out: return skb; }

Contributors

PersonTokensPropCommitsCommitProp
alexey kuznetsovalexey kuznetsov17533.59%36.98%
pre-gitpre-git8015.36%716.28%
david s. millerdavid s. miller6412.28%49.30%
francesco fuscofrancesco fusco417.87%12.33%
herbert xuherbert xu407.68%36.98%
david l stevensdavid l stevens254.80%12.33%
eric dumazeteric dumazet203.84%49.30%
linus torvaldslinus torvalds142.69%49.30%
pavel emelianovpavel emelianov122.30%12.33%
arnaldo carvalho de meloarnaldo carvalho de melo122.30%511.63%
hannes frederic sowahannes frederic sowa122.30%36.98%
laszlo attila tothlaszlo attila toth71.34%12.33%
hideaki yoshifujihideaki yoshifuji61.15%12.33%
ian morrisian morris50.96%12.33%
ansis attekaansis atteka40.77%24.65%
americo wangamerico wang30.58%12.33%
alexey dobriyanalexey dobriyan10.19%12.33%
Total521100.00%43100.00%


int ip_send_skb(struct net *net, struct sk_buff *skb) { int err; err = ip_local_out(net, skb->sk, skb); if (err) { if (err > 0) err = net_xmit_errno(err); if (err) IP_INC_STATS(net, IPSTATS_MIB_OUTDISCARDS); } return err; }

Contributors

PersonTokensPropCommitsCommitProp
alexey kuznetsovalexey kuznetsov2132.81%110.00%
herbert xuherbert xu1726.56%220.00%
pre-gitpre-git1218.75%220.00%
eric w. biedermaneric w. biederman69.38%220.00%
eric dumazeteric dumazet57.81%110.00%
pavel emelianovpavel emelianov23.12%110.00%
hideaki yoshifujihideaki yoshifuji11.56%110.00%
Total64100.00%10100.00%


int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4) { struct sk_buff *skb; skb = ip_finish_skb(sk, fl4); if (!skb) return 0; /* Netfilter gets whole the not fragmented skb. */ return ip_send_skb(sock_net(sk), skb); }

Contributors

PersonTokensPropCommitsCommitProp
herbert xuherbert xu3775.51%250.00%
david s. millerdavid s. miller714.29%125.00%
eric dumazeteric dumazet510.20%125.00%
Total49100.00%4100.00%

/* * Throw away all pending data on the socket. */
static void __ip_flush_pending_frames(struct sock *sk, struct sk_buff_head *queue, struct inet_cork *cork) { struct sk_buff *skb; while ((skb = __skb_dequeue_tail(queue)) != NULL) kfree_skb(skb); ip_cork_release(cork); }

Contributors

PersonTokensPropCommitsCommitProp
alexey kuznetsovalexey kuznetsov2551.02%120.00%
herbert xuherbert xu1734.69%120.00%
pre-gitpre-git612.24%240.00%
pavel emelianovpavel emelianov12.04%120.00%
Total49100.00%5100.00%


void ip_flush_pending_frames(struct sock *sk) { __ip_flush_pending_frames(sk, &sk->sk_write_queue, &inet_sk(sk)->cork.base); }

Contributors

PersonTokensPropCommitsCommitProp
herbert xuherbert xu2170.00%120.00%
pavel emelianovpavel emelianov310.00%120.00%
alexey kuznetsovalexey kuznetsov310.00%120.00%
david s. millerdavid s. miller26.67%120.00%
pre-gitpre-git13.33%120.00%
Total30100.00%5100.00%


struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4, int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb), void *from, int length, int transhdrlen, struct ipcm_cookie *ipc, struct rtable **rtp, unsigned int flags) { struct inet_cork cork; struct sk_buff_head queue; int err; if (flags & MSG_PROBE) return NULL; __skb_queue_head_init(&queue); cork.flags = 0; cork.addr = 0; cork.opt = NULL; err = ip_setup_cork(sk, &cork, ipc, rtp); if (err) return ERR_PTR(err); err = __ip_append_data(sk, fl4, &queue, &cork, &current->task_frag, getfrag, from, length, transhdrlen, flags); if (err) { __ip_flush_pending_frames(sk, &queue, &cork); return ERR_PTR(err); } return __ip_make_skb(sk, fl4, &queue, &cork); }

Contributors

PersonTokensPropCommitsCommitProp
herbert xuherbert xu17184.24%116.67%
david s. millerdavid s. miller2713.30%466.67%
eric dumazeteric dumazet52.46%116.67%
Total203100.00%6100.00%

/* * Fetch data from kernel space and fill in checksum if needed. */
static int ip_reply_glue_bits(void *dptr, char *to, int offset, int len, int odd, struct sk_buff *skb) { __wsum csum; csum = csum_partial_copy_nocheck(dptr+offset, to, len, 0); skb->csum = csum_block_add(skb->csum, csum, odd); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git4570.31%125.00%
alexey kuznetsovalexey kuznetsov1828.12%250.00%
al viroal viro11.56%125.00%
Total64100.00%4100.00%

/* * Generic function to send a packet as reply to another packet. * Used to send some TCP resets/acks so far. */
void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb, const struct ip_options *sopt, __be32 daddr, __be32 saddr, const struct ip_reply_arg *arg, unsigned int len) { struct ip_options_data replyopts; struct ipcm_cookie ipc; struct flowi4 fl4; struct rtable *rt = skb_rtable(skb); struct net *net = sock_net(sk); struct sk_buff *nskb; int err; int oif; if (__ip_options_echo(&replyopts.opt.opt, skb, sopt)) return; ipc.addr = daddr; ipc.opt = NULL; ipc.tx_flags = 0; ipc.ttl = 0; ipc.tos = -1; if (replyopts.opt.opt.optlen) { ipc.opt = &replyopts.opt; if (replyopts.opt.opt.srr) daddr = replyopts.opt.opt.faddr; } oif = arg->bound_dev_if; if (!oif && netif_index_is_l3_master(net, skb->skb_iif)) oif = skb->skb_iif; flowi4_init_output(&fl4, oif, IP4_REPLY_MARK(net, skb->mark), RT_TOS(arg->tos), RT_SCOPE_UNIVERSE, ip_hdr(skb)->protocol, ip_reply_arg_flowi_flags(arg), daddr, saddr, tcp_hdr(skb)->source, tcp_hdr(skb)->dest); security_skb_classify_flow(skb, flowi4_to_flowi(&fl4)); rt = ip_route_output_key(net, &fl4); if (IS_ERR(rt)) return; inet_sk(sk)->tos = arg->tos; sk->sk_priority = skb->priority; sk->sk_protocol = ip_hdr(skb)->protocol; sk->sk_bound_dev_if = arg->bound_dev_if; sk->sk_sndbuf = sysctl_wmem_default; err = ip_append_data(sk, &fl4, ip_reply_glue_bits, arg->iov->iov_base, len, 0, &ipc, &rt, MSG_DONTWAIT); if (unlikely(err)) { ip_flush_pending_frames(sk); goto out; } nskb = skb_peek(&sk->sk_write_queue); if (nskb) { if (arg->csumoffset >= 0) *((__sum16 *)skb_transport_header(nskb) + arg->csumoffset) = csum_fold(csum_add(nskb->csum, arg->csum)); nskb->ip_summed = CHECKSUM_NONE; ip_push_pending_frames(sk, &fl4); } out: ip_rt_put(rt); }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git13730.72%818.60%
eric dumazeteric dumazet6715.02%716.28%
david s. millerdavid s. miller6314.13%920.93%
alexey kuznetsovalexey kuznetsov6213.90%24.65%
david aherndavid ahern306.73%24.65%
vasily averinvasily averin245.38%12.33%
arnaldo carvalho de meloarnaldo carvalho de melo143.14%49.30%
francesco fuscofrancesco fusco132.91%12.33%
patrick mchardypatrick mchardy81.79%12.33%
lorenzo colittilorenzo colitti81.79%12.33%
venkat yekkiralavenkat yekkirala71.57%12.33%
patrick ohlypatrick ohly51.12%12.33%
denis v. lunevdenis v. lunev20.45%12.33%
kovacs krisztiankovacs krisztian20.45%12.33%
changli gaochangli gao20.45%12.33%
al viroal viro10.22%12.33%
oliver hartkoppoliver hartkopp10.22%12.33%
Total446100.00%43100.00%


void __init ip_init(void) { ip_rt_init(); inet_initpeers(); #if defined(CONFIG_IP_MULTICAST) igmp_mc_init(); #endif }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git1664.00%555.56%
stephen hemmingerstephen hemminger520.00%111.11%
david l stevensdavid l stevens28.00%111.11%
hideaki yoshifujihideaki yoshifuji14.00%111.11%
americo wangamerico wang14.00%111.11%
Total25100.00%9100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
alexey kuznetsovalexey kuznetsov209927.08%72.41%
herbert xuherbert xu134817.39%196.53%
pre-gitpre-git115314.87%3411.68%
david s. millerdavid s. miller5707.35%3913.40%
eric dumazeteric dumazet5356.90%268.93%
florian westphalflorian westphal2663.43%51.72%
ananda rajuananda raju2172.80%10.34%
patrick mchardypatrick mchardy1732.23%134.47%
eric w. biedermaneric w. biederman1622.09%175.84%
andy zhouandy zhou1481.91%10.34%
arnaldo carvalho de meloarnaldo carvalho de melo1331.72%206.87%
hannes frederic sowahannes frederic sowa1231.59%103.44%
francesco fuscofrancesco fusco781.01%10.34%
hideaki yoshifujihideaki yoshifuji740.95%82.75%
pavel emelianovpavel emelianov700.90%31.03%
willem de bruijnwillem de bruijn460.59%20.69%
mitsuru chinenmitsuru chinen350.45%10.34%
al viroal viro320.41%103.44%
david aherndavid ahern300.39%20.69%
julian anastasovjulian anastasov280.36%20.69%
jiri pirkojiri pirko270.35%10.34%
david l stevensdavid l stevens270.35%20.69%
steffen klassertsteffen klassert250.32%31.03%
linus torvaldslinus torvalds250.32%51.72%
vasily averinvasily averin240.31%10.34%
neil hormanneil horman240.31%10.34%
laszlo attila tothlaszlo attila toth230.30%10.34%
ian morrisian morris220.28%10.34%
wei dongwei dong200.26%20.69%
kostya belezkokostya belezko160.21%10.34%
bart de schuymerbart de schuymer140.18%10.34%
konstantin khlebnikovkonstantin khlebnikov140.18%10.34%
michal kubecekmichal kubecek130.17%20.69%
joe perchesjoe perches100.13%20.69%
krishna kumarkrishna kumar100.13%10.34%
venkat yekkiralavenkat yekkirala90.12%10.34%
lorenzo colittilorenzo colitti80.10%10.34%
thomas grafthomas graf80.10%10.34%
americo wangamerico wang80.10%20.69%
john heffnerjohn heffner80.10%10.34%
pravin b shelarpravin b shelar70.09%10.34%
james morrisjames morris70.09%10.34%
stephen hemmingerstephen hemminger70.09%31.03%
shmulik ladkanishmulik ladkani60.08%20.69%
patrick ohlypatrick ohly50.06%10.34%
ansis attekaansis atteka50.06%20.69%
tom herberttom herbert50.06%10.34%
jan engelhardtjan engelhardt50.06%10.34%
vasiliy kulikovvasiliy kulikov40.05%10.34%
jozsef kadlecsikjozsef kadlecsik40.05%20.69%
denis v. lunevdenis v. lunev40.05%31.03%
julien tinnesjulien tinnes40.05%10.34%
adrian bunkadrian bunk30.04%31.03%
bill sommerfeldbill sommerfeld30.04%10.34%
marcelo ricardo leitnermarcelo ricardo leitner30.04%10.34%
tejun heotejun heo30.04%10.34%
sridhar samudralasridhar samudrala20.03%10.34%
michel machadomichel machado20.03%10.34%
yasuyuki kozakaiyasuyuki kozakai20.03%10.34%
paul gortmakerpaul gortmaker20.03%10.34%
kovacs krisztiankovacs krisztian20.03%10.34%
shan weishan wei20.03%10.34%
ian campbellian campbell20.03%10.34%
changli gaochangli gao20.03%10.34%
lucas de marchilucas de marchi10.01%10.34%
chuck leverchuck lever10.01%10.34%
octavian purdilaoctavian purdila10.01%10.34%
oliver hartkoppoliver hartkopp10.01%10.34%
alexey dobriyanalexey dobriyan10.01%10.34%
atis elstsatis elsts10.01%10.34%
Total7752100.00%291100.00%
Directory: net/ipv4
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