icmp.c File Reference

#include <linux/config.h>
#include <linux/types.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/fcntl.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/string.h>
#include <linux/netfilter_ipv4.h>
#include <net/snmp.h>
#include <net/ip.h>
#include <net/route.h>
#include <net/protocol.h>
#include <net/icmp.h>
#include <net/tcp.h>
#include <net/udp.h>
#include <net/raw.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <linux/errno.h>
#include <linux/timer.h>
#include <linux/init.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <net/checksum.h>

Go to the source code of this file.

Classes
struct	icmp_bxm
struct	icmp_control
Defines
#define	icmp_socket   (&__icmp_inode[smp_processor_id()].u.socket_i)
#define	icmp_socket_cpu(X)   (&__icmp_inode[(X)].u.socket_i)
#define	XRLIM_BURST_FACTOR   6
Functions
int	icmp_xmit_lock (void)
void	icmp_xmit_unlock (void)
int	xrlim_allow (struct dst_entry *dst, int timeout)
int	icmpv4_xrlim_allow (struct rtable *rt, int type, int code)
void	icmp_out_count (int type)
int	icmp_glue_bits (const void *p, char *to, unsigned int offset, unsigned int fraglen)
void	icmp_reply (struct icmp_bxm *icmp_param, struct sk_buff *skb)
void	icmp_send (struct sk_buff *skb_in, int type, int code, u32 info)
void	icmp_unreach (struct sk_buff *skb)
void	icmp_redirect (struct sk_buff *skb)
void	icmp_echo (struct sk_buff *skb)
void	icmp_timestamp (struct sk_buff *skb)
void	icmp_address (struct sk_buff *skb)
void	icmp_address_reply (struct sk_buff *skb)
void	icmp_discard (struct sk_buff *skb)
int	icmp_rcv (struct sk_buff *skb)
void __init	icmp_init (struct net_proto_family *ops)
Variables
icmp_mib	icmp_statistics [NR_CPUS *2]
icmp_err	icmp_err_convert []
int	sysctl_ip_default_ttl
int	sysctl_icmp_echo_ignore_all
int	sysctl_icmp_echo_ignore_broadcasts
int	sysctl_icmp_ignore_bogus_error_responses
int	sysctl_icmp_ratelimit = 1*HZ
int	sysctl_icmp_ratemask = 0x1818
icmp_control	icmp_pointers [NR_ICMP_TYPES+1]
inode	__icmp_inode [NR_CPUS]

---

Define Documentation

#define icmp_socket   (&__icmp_inode[smp_processor_id()].u.socket_i)

Definition at line 187 of file icmp.c. Referenced by icmp_reply(), icmp_send(), icmp_xmit_lock(), and icmp_xmit_unlock().

#define icmp_socket_cpu (  X   )     (&__icmp_inode[(X)].u.socket_i)

Definition at line 188 of file icmp.c. Referenced by icmp_init().

#define XRLIM_BURST_FACTOR   6

Definition at line 229 of file icmp.c. Referenced by xrlim_allow().

---

Function Documentation

void icmp_address (  struct sk_buff *  skb  )  [static]

Definition at line 808 of file icmp.c. References net_ratelimit(). { #if 0 if (net_ratelimit()) printk(KERN_DEBUG "a guy asks for address mask. Who is it?\n"); #endif }

void icmp_address_reply (  struct sk_buff *  skb  )  [static]

Definition at line 821 of file icmp.c. References sk_buff::dev, sk_buff::dst, IN_DEV_FORWARD, in_dev_get(), IN_DEV_LOG_MARTIANS, in_dev_put(), inet_ifa_match(), sk_buff::len, net_ratelimit(), and skb_copy_bits(). { struct rtable *rt = (struct rtable*)skb->dst; struct net_device *dev = skb->dev; struct in_device *in_dev; struct in_ifaddr *ifa; u32 mask; if (skb->len < 4 || !(rt->rt_flags&RTCF_DIRECTSRC)) return; in_dev = in_dev_get(dev); if (!in_dev) return; read_lock(&in_dev->lock); if (in_dev->ifa_list && IN_DEV_LOG_MARTIANS(in_dev) && IN_DEV_FORWARD(in_dev)) { if (skb_copy_bits(skb, 0, &mask, 4)) BUG(); for (ifa=in_dev->ifa_list; ifa; ifa = ifa->ifa_next) { if (mask == ifa->ifa_mask && inet_ifa_match(rt->rt_src, ifa)) break; } if (!ifa && net_ratelimit()) { printk(KERN_INFO "Wrong address mask %u.%u.%u.%u from %s/%u.%u.%u.%u\n", NIPQUAD(mask), dev->name, NIPQUAD(rt->rt_src)); } } read_unlock(&in_dev->lock); in_dev_put(in_dev); }

void icmp_discard (  struct sk_buff *  skb  )  [static]

Definition at line 854 of file icmp.c. { }

void icmp_echo (  struct sk_buff *  skb  )  [static]

Definition at line 719 of file icmp.c. References icmp_bxm::data, icmp_bxm::data_len, sk_buff::h, icmp_bxm::head_len, icmp_reply(), sk_buff::len, icmp_bxm::offset, icmp_bxm::skb, and sysctl_icmp_echo_ignore_all. { if (!sysctl_icmp_echo_ignore_all) { struct icmp_bxm icmp_param; icmp_param.data.icmph=*skb->h.icmph; icmp_param.data.icmph.type=ICMP_ECHOREPLY; icmp_param.skb=skb; icmp_param.offset=0; icmp_param.data_len=skb->len; icmp_param.head_len=sizeof(struct icmphdr); icmp_reply(&icmp_param, skb); } }

int icmp_glue_bits (  const void *  p, char *  to, unsigned int  offset, unsigned int  fraglen )  [static]

Definition at line 284 of file icmp.c. References csum_fold(), csum_partial_copy_nocheck(), and skb_copy_and_csum_bits(). Referenced by icmp_reply(), and icmp_send(). { struct icmp_bxm *icmp_param = (struct icmp_bxm *)p; struct icmphdr *icmph; unsigned int csum; if (offset) { icmp_param->csum=skb_copy_and_csum_bits(icmp_param->skb, icmp_param->offset+(offset-icmp_param->head_len), to, fraglen,icmp_param->csum); return 0; } /* * First fragment includes header. Note that we've done * the other fragments first, so that we get the checksum * for the whole packet here. */ csum = csum_partial_copy_nocheck((void *)&icmp_param->data, to, icmp_param->head_len, icmp_param->csum); csum=skb_copy_and_csum_bits(icmp_param->skb, icmp_param->offset, to+icmp_param->head_len, fraglen-icmp_param->head_len, csum); icmph=(struct icmphdr *)to; icmph->checksum = csum_fold(csum); return 0; }

void __init icmp_init (  struct net_proto_family *  ops  )

Definition at line 967 of file icmp.c. References __icmp_inode, net_proto_family::create, icmp_socket_cpu, IP_PMTUDISC_DONT, IPPROTO_ICMP, MAXTTL, SK_WMEM_MAX, and SS_UNCONNECTED. Referenced by inet_init(). { int err, i; for (i = 0; i < NR_CPUS; i++) { __icmp_inode[i].i_mode = S_IFSOCK; __icmp_inode[i].i_sock = 1; __icmp_inode[i].i_uid = 0; __icmp_inode[i].i_gid = 0; init_waitqueue_head(&__icmp_inode[i].i_wait); init_waitqueue_head(&__icmp_inode[i].u.socket_i.wait); icmp_socket_cpu(i)->inode = &__icmp_inode[i]; icmp_socket_cpu(i)->state = SS_UNCONNECTED; icmp_socket_cpu(i)->type = SOCK_RAW; if ((err=ops->create(icmp_socket_cpu(i), IPPROTO_ICMP)) < 0) panic("Failed to create the ICMP control socket.\n"); icmp_socket_cpu(i)->sk->allocation=GFP_ATOMIC; icmp_socket_cpu(i)->sk->sndbuf = SK_WMEM_MAX*2; icmp_socket_cpu(i)->sk->protinfo.af_inet.ttl = MAXTTL; icmp_socket_cpu(i)->sk->protinfo.af_inet.pmtudisc = IP_PMTUDISC_DONT; /* Unhash it so that IP input processing does not even * see it, we do not wish this socket to see incoming * packets. */ icmp_socket_cpu(i)->sk->prot->unhash(icmp_socket_cpu(i)->sk); } }

void icmp_out_count (  int  type  )  [static]

Definition at line 272 of file icmp.c. References ICMP_INC_STATS, icmp_pointers, and icmp_control::output. Referenced by icmp_reply(), and icmp_send(). { if (type>NR_ICMP_TYPES) return; (icmp_pointers[type].output)[(smp_processor_id()*2+!in_softirq())*sizeof(struct icmp_mib)/sizeof(unsigned long)]++; ICMP_INC_STATS(IcmpOutMsgs); }

int icmp_rcv (  struct sk_buff *  skb  )

Definition at line 862 of file icmp.c. References CHECKSUM_HW, CHECKSUM_NONE, sk_buff::csum, csum_fold(), sk_buff::dst, error, sk_buff::h, icmp_control::handler, ICMP_INC_STATS_BH, icmp_pointers, icmp_control::input, sk_buff::ip_summed, kfree_skb(), sk_buff::len, net_ratelimit(), NETDEBUG, pskb_pull(), skb_checksum(), and sysctl_icmp_echo_ignore_broadcasts. { struct icmphdr *icmph; struct rtable *rt = (struct rtable*)skb->dst; ICMP_INC_STATS_BH(IcmpInMsgs); switch (skb->ip_summed) { case CHECKSUM_HW: if ((u16)csum_fold(skb->csum) == 0) break; NETDEBUG(if (net_ratelimit()) printk(KERN_DEBUG "icmp v4 hw csum failure\n")); case CHECKSUM_NONE: if ((u16)csum_fold(skb_checksum(skb, 0, skb->len, 0))) goto error; default:; } if (!pskb_pull(skb, sizeof(struct icmphdr))) goto error; icmph = skb->h.icmph; /* * 18 is the highest 'known' ICMP type. Anything else is a mystery * * RFC 1122: 3.2.2 Unknown ICMP messages types MUST be silently discarded. */ if (icmph->type > NR_ICMP_TYPES) goto error; /* * Parse the ICMP message */ if (rt->rt_flags&(RTCF_BROADCAST|RTCF_MULTICAST)) { /* * RFC 1122: 3.2.2.6 An ICMP_ECHO to broadcast MAY be * silently ignored (we let user decide with a sysctl). * RFC 1122: 3.2.2.8 An ICMP_TIMESTAMP MAY be silently * discarded if to broadcast/multicast. */ if (icmph->type == ICMP_ECHO && sysctl_icmp_echo_ignore_broadcasts) { goto error; } if (icmph->type != ICMP_ECHO && icmph->type != ICMP_TIMESTAMP && icmph->type != ICMP_ADDRESS && icmph->type != ICMP_ADDRESSREPLY) { goto error; } } icmp_pointers[icmph->type].input[smp_processor_id()*2*sizeof(struct icmp_mib)/sizeof(unsigned long)]++; (icmp_pointers[icmph->type].handler)(skb); drop: kfree_skb(skb); return 0; error: ICMP_INC_STATS_BH(IcmpInErrors); goto drop; }

void icmp_redirect (  struct sk_buff *  skb  )  [static]

Definition at line 674 of file icmp.c. References sk_buff::data, sk_buff::dev, sk_buff::h, ICMP_INC_STATS_BH, ip_rt_redirect(), sk_buff::len, sk_buff::nh, and pskb_may_pull(). { struct iphdr *iph; unsigned long ip; if (skb->len < sizeof(struct iphdr)) { ICMP_INC_STATS_BH(IcmpInErrors); return; } /* * Get the copied header of the packet that caused the redirect */ if (!pskb_may_pull(skb, sizeof(struct iphdr))) return; iph = (struct iphdr *) skb->data; ip = iph->daddr; switch (skb->h.icmph->code & 7) { case ICMP_REDIR_NET: case ICMP_REDIR_NETTOS: /* * As per RFC recommendations now handle it as * a host redirect. */ case ICMP_REDIR_HOST: case ICMP_REDIR_HOSTTOS: ip_rt_redirect(skb->nh.iph->saddr, ip, skb->h.icmph->un.gateway, iph->saddr, iph->tos, skb->dev); break; default: break; } }

void icmp_reply (  struct icmp_bxm *  icmp_param, struct sk_buff *  skb )  [static]

Driving logic for building and sending ICMP messages. if the ICMP is not to be echoed, then drop Definition at line 318 of file icmp.c. References ipcm_cookie::addr, icmp_bxm::csum, icmp_bxm::data, icmp_bxm::data_len, sk_buff::dst, ip_options::faddr, icmp_bxm::head_len, icmp_glue_bits(), icmp_out_count(), icmp_socket, icmp_xmit_lock(), icmp_xmit_unlock(), icmpv4_xrlim_allow(), ip_build_xmit(), ip_options_echo(), ip_route_output(), ip_rt_put(), sk_buff::nh, ipcm_cookie::opt, ip_options::optlen, icmp_bxm::replyopts, ip_options::srr, and sysctl_ip_default_ttl. Referenced by icmp_echo(), and icmp_timestamp(). { struct sock *sk=icmp_socket->sk; struct ipcm_cookie ipc; struct rtable *rt = (struct rtable*)skb->dst; u32 daddr; if (ip_options_echo(&icmp_param->replyopts, skb)) return; if (icmp_xmit_lock()) return; icmp_param->data.icmph.checksum=0; icmp_param->csum=0; icmp_out_count(icmp_param->data.icmph.type); sk->protinfo.af_inet.tos = skb->nh.iph->tos; sk->protinfo.af_inet.ttl = sysctl_ip_default_ttl; daddr = ipc.addr = rt->rt_src; ipc.opt = NULL; if (icmp_param->replyopts.optlen) { ipc.opt = &icmp_param->replyopts; if (ipc.opt->srr) daddr = icmp_param->replyopts.faddr; } if (ip_route_output(&rt, daddr, rt->rt_spec_dst, RT_TOS(skb->nh.iph->tos), 0)) goto out; if (icmpv4_xrlim_allow(rt, icmp_param->data.icmph.type, icmp_param->data.icmph.code)) { ip_build_xmit(sk, icmp_glue_bits, icmp_param, icmp_param->data_len+icmp_param->head_len, &ipc, rt, MSG_DONTWAIT); } ip_rt_put(rt); out: icmp_xmit_unlock(); }

void icmp_send (  struct sk_buff *  skb_in, int  type, int  code, u32  info )

Definition at line 369 of file icmp.c. References ipcm_cookie::addr, icmp_bxm::csum, icmp_bxm::data, sk_buff::data, sk_buff::dst, icmp_control::error, ip_options::faddr, sk_buff::head, icmp_glue_bits(), icmp_out_count(), icmp_pointers, icmp_socket, icmp_xmit_lock(), icmp_xmit_unlock(), icmpv4_xrlim_allow(), ip_build_xmit(), IP_OFFSET, ip_options_echo(), ip_route_output(), ip_rt_put(), IPCB, IPPROTO_ICMP, IPSKB_TRANSLATED, IPTOS_PREC_INTERNETCONTROL, IPTOS_TOS_MASK, sk_buff::len, sk_buff::nh, icmp_bxm::offset, ipcm_cookie::opt, sk_buff::pkt_type, icmp_bxm::replyopts, icmp_bxm::skb, skb_copy_bits(), ip_options::srr, sysctl_ip_default_ttl, and sk_buff::tail. Referenced by fw_in(), ip_error(), ip_expire(), ip_forward(), ip_local_deliver_finish(), ip_options_compile(), ip_options_rcv_srr(), ip_queue_xmit2(), ip_rt_send_redirect(), ip_vs_bypass_xmit(), ip_vs_dr_xmit(), ip_vs_in_icmp(), ip_vs_leave(), ip_vs_nat_xmit(), ip_vs_out(), ip_vs_tunnel_xmit(), ipgre_err(), ipgre_rcv(), ipgre_tunnel_xmit(), ipip_err(), ipip_rcv(), ipip_tunnel_xmit(), ipt_mirror_target(), ipv4_link_failure(), and udp_rcv(). { struct iphdr *iph; int room; struct icmp_bxm icmp_param; struct rtable *rt = (struct rtable*)skb_in->dst; struct ipcm_cookie ipc; u32 saddr; u8 tos; if (!rt) return; /* * Find the original header. It is expected to be valid, of course. * Check this, icmp_send is called from the most obscure devices * sometimes. */ iph = skb_in->nh.iph; if ((u8*)iph < skb_in->head || (u8*)(iph+1) > skb_in->tail) return; /* * No replies to physical multicast/broadcast */ if (skb_in->pkt_type!=PACKET_HOST) return; /* * Now check at the protocol level */ if (rt->rt_flags&(RTCF_BROADCAST|RTCF_MULTICAST)) return; /* * Only reply to fragment 0. We byte re-order the constant * mask for efficiency. */ if (iph->frag_off&htons(IP_OFFSET)) return; /* * If we send an ICMP error to an ICMP error a mess would result.. */ if (icmp_pointers[type].error) { /* * We are an error, check if we are replying to an ICMP error */ if (iph->protocol==IPPROTO_ICMP) { u8 inner_type; if (skb_copy_bits(skb_in, skb_in->nh.raw + (iph->ihl<<2) + offsetof(struct icmphdr, type) - skb_in->data, &inner_type, 1)) return; /* * Assume any unknown ICMP type is an error. This isn't * specified by the RFC, but think about it.. */ if (inner_type>NR_ICMP_TYPES || icmp_pointers[inner_type].error) return; } } if (icmp_xmit_lock()) return; /* * Construct source address and options. */ #ifdef CONFIG_IP_ROUTE_NAT /* * Restore original addresses if packet has been translated. */ if (rt->rt_flags&RTCF_NAT && IPCB(skb_in)->flags&IPSKB_TRANSLATED) { iph->daddr = rt->key.dst; iph->saddr = rt->key.src; } #endif saddr = iph->daddr; if (!(rt->rt_flags & RTCF_LOCAL)) saddr = 0; tos = icmp_pointers[type].error ? ((iph->tos & IPTOS_TOS_MASK) | IPTOS_PREC_INTERNETCONTROL) : iph->tos; if (ip_route_output(&rt, iph->saddr, saddr, RT_TOS(tos), 0)) goto out; if (ip_options_echo(&icmp_param.replyopts, skb_in)) goto ende; /* * Prepare data for ICMP header. */ icmp_param.data.icmph.type=type; icmp_param.data.icmph.code=code; icmp_param.data.icmph.un.gateway = info; icmp_param.data.icmph.checksum=0; icmp_param.csum=0; icmp_param.skb=skb_in; icmp_param.offset=skb_in->nh.raw - skb_in->data; icmp_out_count(icmp_param.data.icmph.type); icmp_socket->sk->protinfo.af_inet.tos = tos; icmp_socket->sk->protinfo.af_inet.ttl = sysctl_ip_default_ttl; ipc.addr = iph->saddr; ipc.opt = &icmp_param.replyopts; if (icmp_param.replyopts.srr) { ip_rt_put(rt); if (ip_route_output(&rt, icmp_param.replyopts.faddr, saddr, RT_TOS(tos), 0)) goto out; } if (!icmpv4_xrlim_allow(rt, type, code)) goto ende; /* RFC says return as much as we can without exceeding 576 bytes. */ room = rt->u.dst.pmtu; if (room > 576) room = 576; room -= sizeof(struct iphdr) + icmp_param.replyopts.optlen; room -= sizeof(struct icmphdr); icmp_param.data_len=skb_in->len-icmp_param.offset; if (icmp_param.data_len > room) icmp_param.data_len = room; icmp_param.head_len = sizeof(struct icmphdr); ip_build_xmit(icmp_socket->sk, icmp_glue_bits, &icmp_param, icmp_param.data_len+sizeof(struct icmphdr), &ipc, rt, MSG_DONTWAIT); ende: ip_rt_put(rt); out: icmp_xmit_unlock(); }

void icmp_timestamp (  struct sk_buff *  skb  )  [static]

Definition at line 742 of file icmp.c. References icmp_bxm::data, icmp_bxm::data_len, sk_buff::h, icmp_bxm::head_len, ICMP_INC_STATS_BH, icmp_reply(), sk_buff::len, icmp_bxm::offset, icmp_bxm::skb, and skb_copy_bits(). { struct timeval tv; struct icmp_bxm icmp_param; /* * Too short. */ if (skb->len < 4) { ICMP_INC_STATS_BH(IcmpInErrors); return; } /* * Fill in the current time as ms since midnight UT: */ do_gettimeofday(&tv); icmp_param.data.times[1] = htonl((tv.tv_sec % 86400) * 1000 + tv.tv_usec / 1000); icmp_param.data.times[2] = icmp_param.data.times[1]; if (skb_copy_bits(skb, 0, &icmp_param.data.times[0], 4)) BUG(); icmp_param.data.icmph=*skb->h.icmph; icmp_param.data.icmph.type=ICMP_TIMESTAMPREPLY; icmp_param.data.icmph.code=0; icmp_param.skb=skb; icmp_param.offset=0; icmp_param.data_len=0; icmp_param.head_len=sizeof(struct icmphdr)+12; icmp_reply(&icmp_param, skb); }

void icmp_unreach (  struct sk_buff *  skb  )  [static]

Definition at line 522 of file icmp.c. References __raw_v4_lookup(), sk_buff::data, sk_buff::dev, inet_protocol::err_handler, sk_buff::h, ICMP_INC_STATS_BH, net_device::ifindex, inet_addr_type(), inet_protos, ip_rt_frag_needed(), MAX_INET_PROTOS, net_device::name, net_ratelimit(), inet_protocol::next, pskb_may_pull(), raw_err(), raw_v4_htable, raw_v4_lock, and sysctl_icmp_ignore_bogus_error_responses. { struct iphdr *iph; struct icmphdr *icmph; int hash, protocol; struct inet_protocol *ipprot; struct sock *raw_sk; u32 info = 0; /* * Incomplete header ? * Only checks for the IP header, there should be an * additional check for longer headers in upper levels. */ if (!pskb_may_pull(skb, sizeof(struct iphdr))) { ICMP_INC_STATS_BH(IcmpInErrors); return; } icmph = skb->h.icmph; iph = (struct iphdr *) skb->data; if (iph->ihl<5) { /* Mangled header, drop. */ ICMP_INC_STATS_BH(IcmpInErrors); return; } if(icmph->type==ICMP_DEST_UNREACH) { switch(icmph->code & 15) { case ICMP_NET_UNREACH: break; case ICMP_HOST_UNREACH: break; case ICMP_PROT_UNREACH: break; case ICMP_PORT_UNREACH: break; case ICMP_FRAG_NEEDED: if (ipv4_config.no_pmtu_disc) { if (net_ratelimit()) printk(KERN_INFO "ICMP: %u.%u.%u.%u: fragmentation needed and DF set.\n", NIPQUAD(iph->daddr)); } else { info = ip_rt_frag_needed(iph, ntohs(icmph->un.frag.mtu)); if (!info) goto out; } break; case ICMP_SR_FAILED: if (net_ratelimit()) printk(KERN_INFO "ICMP: %u.%u.%u.%u: Source Route Failed.\n", NIPQUAD(iph->daddr)); break; default: break; } if (icmph->code>NR_ICMP_UNREACH) goto out; } else if (icmph->type == ICMP_PARAMETERPROB) { info = ntohl(icmph->un.gateway)>>24; } /* * Throw it at our lower layers * * RFC 1122: 3.2.2 MUST extract the protocol ID from the passed header. * RFC 1122: 3.2.2.1 MUST pass ICMP unreach messages to the transport layer. * RFC 1122: 3.2.2.2 MUST pass ICMP time expired messages to transport layer. */ /* * Check the other end isnt violating RFC 1122. Some routers send * bogus responses to broadcast frames. If you see this message * first check your netmask matches at both ends, if it does then * get the other vendor to fix their kit. */ if (!sysctl_icmp_ignore_bogus_error_responses) { if (inet_addr_type(iph->daddr) == RTN_BROADCAST) { if (net_ratelimit()) printk(KERN_WARNING "%u.%u.%u.%u sent an invalid ICMP type %u, code %u error to a broadcast: %u.%u.%u.%u on %s\n", NIPQUAD(iph->saddr), icmph->type, icmph->code, NIPQUAD(iph->daddr), skb->dev->name); goto out; } } /* Checkin full IP header plus 8 bytes of protocol to * avoid additional coding at protocol handlers. */ if (!pskb_may_pull(skb, iph->ihl*4+8)) goto out; iph = (struct iphdr *) skb->data; protocol = iph->protocol; /* * Deliver ICMP message to raw sockets. Pretty useless feature? */ /* Note: See raw.c and net/raw.h, RAWV4_HTABLE_SIZE==MAX_INET_PROTOS */ hash = protocol & (MAX_INET_PROTOS - 1); read_lock(&raw_v4_lock); if ((raw_sk = raw_v4_htable[hash]) != NULL) { while ((raw_sk = __raw_v4_lookup(raw_sk, protocol, iph->daddr, iph->saddr, skb->dev->ifindex)) != NULL) { raw_err(raw_sk, skb, info); raw_sk = raw_sk->next; iph = (struct iphdr *)skb->data; } } read_unlock(&raw_v4_lock); /* * This can't change while we are doing it. * Callers have obtained BR_NETPROTO_LOCK so * we are OK. */ ipprot = (struct inet_protocol *) inet_protos[hash]; while (ipprot) { struct inet_protocol *nextip; nextip = (struct inet_protocol *) ipprot->next; /* * Pass it off to everyone who wants it. */ /* RFC1122: OK. Passes appropriate ICMP errors to the */ /* appropriate protocol layer (MUST), as per 3.2.2. */ if (protocol == ipprot->protocol && ipprot->err_handler) ipprot->err_handler(skb, info); ipprot = nextip; } out:; }

int icmp_xmit_lock (  void   )  [static]

Definition at line 190 of file icmp.c. References icmp_socket. Referenced by icmp_reply(), and icmp_send(). { local_bh_disable(); if (unlikely(!spin_trylock(&icmp_socket->sk->lock.slock))) { /* This can happen if the output path signals a * dst_link_failure() for an outgoing ICMP packet. */ local_bh_enable(); return 1; } return 0; }

void icmp_xmit_unlock (  void   )  [static]

Definition at line 203 of file icmp.c. References icmp_socket. Referenced by icmp_reply(), and icmp_send(). { spin_unlock_bh(&icmp_socket->sk->lock.slock); }

int icmpv4_xrlim_allow (  struct rtable *  rt, int  type, int  code )  [inline, static]

Definition at line 246 of file icmp.c. References sysctl_icmp_ratelimit, sysctl_icmp_ratemask, rtable::u, and xrlim_allow(). Referenced by icmp_reply(), and icmp_send(). { struct dst_entry *dst = &rt->u.dst; if (type > NR_ICMP_TYPES) return 1; /* Don't limit PMTU discovery. */ if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) return 1; /* No rate limit on loopback */ if (dst->dev && (dst->dev->flags&IFF_LOOPBACK)) return 1; /* Limit if icmp type is enabled in ratemask. */ if((1 << type) & sysctl_icmp_ratemask) return xrlim_allow(dst, sysctl_icmp_ratelimit); else return 1; }

int xrlim_allow (  struct dst_entry *  dst, int  timeout )

Definition at line 230 of file icmp.c. References dst_entry::rate_last, dst_entry::rate_tokens, and XRLIM_BURST_FACTOR. Referenced by icmpv4_xrlim_allow(), and send_unreach(). { unsigned long now; now = jiffies; dst->rate_tokens += now - dst->rate_last; dst->rate_last = now; if (dst->rate_tokens > XRLIM_BURST_FACTOR*timeout) dst->rate_tokens = XRLIM_BURST_FACTOR*timeout; if (dst->rate_tokens >= timeout) { dst->rate_tokens -= timeout; return 1; } return 0; }

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Variable Documentation

struct inode __icmp_inode[NR_CPUS] [static]

Definition at line 186 of file icmp.c. Referenced by icmp_init().

struct icmp_err icmp_err_convert[]

Initial value: { { ENETUNREACH, 0 }, { EHOSTUNREACH, 0 }, { ENOPROTOOPT, 1 }, { ECONNREFUSED, 1 }, { EMSGSIZE, 0 }, { EOPNOTSUPP, 0 }, { ENETUNREACH, 1 }, { EHOSTDOWN, 1 }, { ENONET, 1 }, { ENETUNREACH, 1 }, { EHOSTUNREACH, 1 }, { ENETUNREACH, 0 }, { EHOSTUNREACH, 0 }, { EHOSTUNREACH, 1 }, { EHOSTUNREACH, 1 }, { EHOSTUNREACH, 1 } } Definition at line 123 of file icmp.c. Referenced by raw_err(), tcp_v4_err(), and udp_err().

struct icmp_control icmp_pointers [static]

Definition at line 932 of file icmp.c. Referenced by icmp_out_count(), icmp_rcv(), and icmp_send().

struct icmp_mib icmp_statistics[NR_CPUS *2]

Definition at line 118 of file icmp.c. Referenced by snmp_get_info().

int sysctl_icmp_echo_ignore_all

Definition at line 145 of file icmp.c. Referenced by icmp_echo().

int sysctl_icmp_echo_ignore_broadcasts

Definition at line 146 of file icmp.c. Referenced by icmp_rcv().

int sysctl_icmp_ignore_bogus_error_responses

Definition at line 149 of file icmp.c. Referenced by icmp_unreach().

int sysctl_icmp_ratelimit = 1*HZ

Definition at line 163 of file icmp.c. Referenced by icmpv4_xrlim_allow().

int sysctl_icmp_ratemask = 0x1818

Definition at line 164 of file icmp.c. Referenced by icmpv4_xrlim_allow().

int sysctl_ip_default_ttl

Definition at line 86 of file ip_output.c.

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