You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
843 lines
19 KiB
843 lines
19 KiB
/*
|
|
* Internet Control Message Protocol (ICMPv6)
|
|
* Linux INET6 implementation
|
|
*
|
|
* Authors:
|
|
* Pedro Roque <roque@di.fc.ul.pt>
|
|
*
|
|
* $Id: icmp.c,v 1.38 2002/02/08 03:57:19 davem Exp $
|
|
*
|
|
* Based on net/ipv4/icmp.c
|
|
*
|
|
* RFC 1885
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
/*
|
|
* Changes:
|
|
*
|
|
* Andi Kleen : exception handling
|
|
* Andi Kleen add rate limits. never reply to a icmp.
|
|
* add more length checks and other fixes.
|
|
* yoshfuji : ensure to sent parameter problem for
|
|
* fragments.
|
|
* YOSHIFUJI Hideaki @USAGI: added sysctl for icmp rate limit.
|
|
* Randy Dunlap and
|
|
* YOSHIFUJI Hideaki @USAGI: Per-interface statistics support
|
|
* Kazunori MIYAZAWA @USAGI: change output process to use ip6_append_data
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/types.h>
|
|
#include <linux/socket.h>
|
|
#include <linux/in.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/sockios.h>
|
|
#include <linux/net.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/init.h>
|
|
#include <linux/netfilter.h>
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
#include <linux/sysctl.h>
|
|
#endif
|
|
|
|
#include <linux/inet.h>
|
|
#include <linux/netdevice.h>
|
|
#include <linux/icmpv6.h>
|
|
|
|
#include <net/ip.h>
|
|
#include <net/sock.h>
|
|
|
|
#include <net/ipv6.h>
|
|
#include <net/ip6_checksum.h>
|
|
#include <net/protocol.h>
|
|
#include <net/raw.h>
|
|
#include <net/rawv6.h>
|
|
#include <net/transp_v6.h>
|
|
#include <net/ip6_route.h>
|
|
#include <net/addrconf.h>
|
|
#include <net/icmp.h>
|
|
|
|
#include <asm/uaccess.h>
|
|
#include <asm/system.h>
|
|
|
|
DEFINE_SNMP_STAT(struct icmpv6_mib, icmpv6_statistics) __read_mostly;
|
|
|
|
/*
|
|
* The ICMP socket(s). This is the most convenient way to flow control
|
|
* our ICMP output as well as maintain a clean interface throughout
|
|
* all layers. All Socketless IP sends will soon be gone.
|
|
*
|
|
* On SMP we have one ICMP socket per-cpu.
|
|
*/
|
|
static DEFINE_PER_CPU(struct socket *, __icmpv6_socket) = NULL;
|
|
#define icmpv6_socket __get_cpu_var(__icmpv6_socket)
|
|
|
|
static int icmpv6_rcv(struct sk_buff **pskb);
|
|
|
|
static struct inet6_protocol icmpv6_protocol = {
|
|
.handler = icmpv6_rcv,
|
|
.flags = INET6_PROTO_FINAL,
|
|
};
|
|
|
|
static __inline__ int icmpv6_xmit_lock(void)
|
|
{
|
|
local_bh_disable();
|
|
|
|
if (unlikely(!spin_trylock(&icmpv6_socket->sk->sk_lock.slock))) {
|
|
/* This can happen if the output path (f.e. SIT or
|
|
* ip6ip6 tunnel) signals dst_link_failure() for an
|
|
* outgoing ICMP6 packet.
|
|
*/
|
|
local_bh_enable();
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static __inline__ void icmpv6_xmit_unlock(void)
|
|
{
|
|
spin_unlock_bh(&icmpv6_socket->sk->sk_lock.slock);
|
|
}
|
|
|
|
/*
|
|
* Slightly more convenient version of icmpv6_send.
|
|
*/
|
|
void icmpv6_param_prob(struct sk_buff *skb, int code, int pos)
|
|
{
|
|
icmpv6_send(skb, ICMPV6_PARAMPROB, code, pos, skb->dev);
|
|
kfree_skb(skb);
|
|
}
|
|
|
|
/*
|
|
* Figure out, may we reply to this packet with icmp error.
|
|
*
|
|
* We do not reply, if:
|
|
* - it was icmp error message.
|
|
* - it is truncated, so that it is known, that protocol is ICMPV6
|
|
* (i.e. in the middle of some exthdr)
|
|
*
|
|
* --ANK (980726)
|
|
*/
|
|
|
|
static int is_ineligible(struct sk_buff *skb)
|
|
{
|
|
int ptr = (u8*)(skb->nh.ipv6h+1) - skb->data;
|
|
int len = skb->len - ptr;
|
|
__u8 nexthdr = skb->nh.ipv6h->nexthdr;
|
|
|
|
if (len < 0)
|
|
return 1;
|
|
|
|
ptr = ipv6_skip_exthdr(skb, ptr, &nexthdr);
|
|
if (ptr < 0)
|
|
return 0;
|
|
if (nexthdr == IPPROTO_ICMPV6) {
|
|
u8 _type, *tp;
|
|
tp = skb_header_pointer(skb,
|
|
ptr+offsetof(struct icmp6hdr, icmp6_type),
|
|
sizeof(_type), &_type);
|
|
if (tp == NULL ||
|
|
!(*tp & ICMPV6_INFOMSG_MASK))
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int sysctl_icmpv6_time = 1*HZ;
|
|
|
|
/*
|
|
* Check the ICMP output rate limit
|
|
*/
|
|
static inline int icmpv6_xrlim_allow(struct sock *sk, int type,
|
|
struct flowi *fl)
|
|
{
|
|
struct dst_entry *dst;
|
|
int res = 0;
|
|
|
|
/* Informational messages are not limited. */
|
|
if (type & ICMPV6_INFOMSG_MASK)
|
|
return 1;
|
|
|
|
/* Do not limit pmtu discovery, it would break it. */
|
|
if (type == ICMPV6_PKT_TOOBIG)
|
|
return 1;
|
|
|
|
/*
|
|
* Look up the output route.
|
|
* XXX: perhaps the expire for routing entries cloned by
|
|
* this lookup should be more aggressive (not longer than timeout).
|
|
*/
|
|
dst = ip6_route_output(sk, fl);
|
|
if (dst->error) {
|
|
IP6_INC_STATS(IPSTATS_MIB_OUTNOROUTES);
|
|
} else if (dst->dev && (dst->dev->flags&IFF_LOOPBACK)) {
|
|
res = 1;
|
|
} else {
|
|
struct rt6_info *rt = (struct rt6_info *)dst;
|
|
int tmo = sysctl_icmpv6_time;
|
|
|
|
/* Give more bandwidth to wider prefixes. */
|
|
if (rt->rt6i_dst.plen < 128)
|
|
tmo >>= ((128 - rt->rt6i_dst.plen)>>5);
|
|
|
|
res = xrlim_allow(dst, tmo);
|
|
}
|
|
dst_release(dst);
|
|
return res;
|
|
}
|
|
|
|
/*
|
|
* an inline helper for the "simple" if statement below
|
|
* checks if parameter problem report is caused by an
|
|
* unrecognized IPv6 option that has the Option Type
|
|
* highest-order two bits set to 10
|
|
*/
|
|
|
|
static __inline__ int opt_unrec(struct sk_buff *skb, __u32 offset)
|
|
{
|
|
u8 _optval, *op;
|
|
|
|
offset += skb->nh.raw - skb->data;
|
|
op = skb_header_pointer(skb, offset, sizeof(_optval), &_optval);
|
|
if (op == NULL)
|
|
return 1;
|
|
return (*op & 0xC0) == 0x80;
|
|
}
|
|
|
|
static int icmpv6_push_pending_frames(struct sock *sk, struct flowi *fl, struct icmp6hdr *thdr, int len)
|
|
{
|
|
struct sk_buff *skb;
|
|
struct icmp6hdr *icmp6h;
|
|
int err = 0;
|
|
|
|
if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
|
|
goto out;
|
|
|
|
icmp6h = (struct icmp6hdr*) skb->h.raw;
|
|
memcpy(icmp6h, thdr, sizeof(struct icmp6hdr));
|
|
icmp6h->icmp6_cksum = 0;
|
|
|
|
if (skb_queue_len(&sk->sk_write_queue) == 1) {
|
|
skb->csum = csum_partial((char *)icmp6h,
|
|
sizeof(struct icmp6hdr), skb->csum);
|
|
icmp6h->icmp6_cksum = csum_ipv6_magic(&fl->fl6_src,
|
|
&fl->fl6_dst,
|
|
len, fl->proto,
|
|
skb->csum);
|
|
} else {
|
|
u32 tmp_csum = 0;
|
|
|
|
skb_queue_walk(&sk->sk_write_queue, skb) {
|
|
tmp_csum = csum_add(tmp_csum, skb->csum);
|
|
}
|
|
|
|
tmp_csum = csum_partial((char *)icmp6h,
|
|
sizeof(struct icmp6hdr), tmp_csum);
|
|
tmp_csum = csum_ipv6_magic(&fl->fl6_src,
|
|
&fl->fl6_dst,
|
|
len, fl->proto, tmp_csum);
|
|
icmp6h->icmp6_cksum = tmp_csum;
|
|
}
|
|
if (icmp6h->icmp6_cksum == 0)
|
|
icmp6h->icmp6_cksum = -1;
|
|
ip6_push_pending_frames(sk);
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
struct icmpv6_msg {
|
|
struct sk_buff *skb;
|
|
int offset;
|
|
uint8_t type;
|
|
};
|
|
|
|
static int icmpv6_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb)
|
|
{
|
|
struct icmpv6_msg *msg = (struct icmpv6_msg *) from;
|
|
struct sk_buff *org_skb = msg->skb;
|
|
__u32 csum = 0;
|
|
|
|
csum = skb_copy_and_csum_bits(org_skb, msg->offset + offset,
|
|
to, len, csum);
|
|
skb->csum = csum_block_add(skb->csum, csum, odd);
|
|
if (!(msg->type & ICMPV6_INFOMSG_MASK))
|
|
nf_ct_attach(skb, org_skb);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Send an ICMP message in response to a packet in error
|
|
*/
|
|
void icmpv6_send(struct sk_buff *skb, int type, int code, __u32 info,
|
|
struct net_device *dev)
|
|
{
|
|
struct inet6_dev *idev = NULL;
|
|
struct ipv6hdr *hdr = skb->nh.ipv6h;
|
|
struct sock *sk;
|
|
struct ipv6_pinfo *np;
|
|
struct in6_addr *saddr = NULL;
|
|
struct dst_entry *dst;
|
|
struct icmp6hdr tmp_hdr;
|
|
struct flowi fl;
|
|
struct icmpv6_msg msg;
|
|
int iif = 0;
|
|
int addr_type = 0;
|
|
int len;
|
|
int hlimit, tclass;
|
|
int err = 0;
|
|
|
|
if ((u8*)hdr < skb->head || (u8*)(hdr+1) > skb->tail)
|
|
return;
|
|
|
|
/*
|
|
* Make sure we respect the rules
|
|
* i.e. RFC 1885 2.4(e)
|
|
* Rule (e.1) is enforced by not using icmpv6_send
|
|
* in any code that processes icmp errors.
|
|
*/
|
|
addr_type = ipv6_addr_type(&hdr->daddr);
|
|
|
|
if (ipv6_chk_addr(&hdr->daddr, skb->dev, 0))
|
|
saddr = &hdr->daddr;
|
|
|
|
/*
|
|
* Dest addr check
|
|
*/
|
|
|
|
if ((addr_type & IPV6_ADDR_MULTICAST || skb->pkt_type != PACKET_HOST)) {
|
|
if (type != ICMPV6_PKT_TOOBIG &&
|
|
!(type == ICMPV6_PARAMPROB &&
|
|
code == ICMPV6_UNK_OPTION &&
|
|
(opt_unrec(skb, info))))
|
|
return;
|
|
|
|
saddr = NULL;
|
|
}
|
|
|
|
addr_type = ipv6_addr_type(&hdr->saddr);
|
|
|
|
/*
|
|
* Source addr check
|
|
*/
|
|
|
|
if (addr_type & IPV6_ADDR_LINKLOCAL)
|
|
iif = skb->dev->ifindex;
|
|
|
|
/*
|
|
* Must not send error if the source does not uniquely
|
|
* identify a single node (RFC2463 Section 2.4).
|
|
* We check unspecified / multicast addresses here,
|
|
* and anycast addresses will be checked later.
|
|
*/
|
|
if ((addr_type == IPV6_ADDR_ANY) || (addr_type & IPV6_ADDR_MULTICAST)) {
|
|
LIMIT_NETDEBUG(KERN_DEBUG "icmpv6_send: addr_any/mcast source\n");
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Never answer to a ICMP packet.
|
|
*/
|
|
if (is_ineligible(skb)) {
|
|
LIMIT_NETDEBUG(KERN_DEBUG "icmpv6_send: no reply to icmp error\n");
|
|
return;
|
|
}
|
|
|
|
memset(&fl, 0, sizeof(fl));
|
|
fl.proto = IPPROTO_ICMPV6;
|
|
ipv6_addr_copy(&fl.fl6_dst, &hdr->saddr);
|
|
if (saddr)
|
|
ipv6_addr_copy(&fl.fl6_src, saddr);
|
|
fl.oif = iif;
|
|
fl.fl_icmp_type = type;
|
|
fl.fl_icmp_code = code;
|
|
|
|
if (icmpv6_xmit_lock())
|
|
return;
|
|
|
|
sk = icmpv6_socket->sk;
|
|
np = inet6_sk(sk);
|
|
|
|
if (!icmpv6_xrlim_allow(sk, type, &fl))
|
|
goto out;
|
|
|
|
tmp_hdr.icmp6_type = type;
|
|
tmp_hdr.icmp6_code = code;
|
|
tmp_hdr.icmp6_cksum = 0;
|
|
tmp_hdr.icmp6_pointer = htonl(info);
|
|
|
|
if (!fl.oif && ipv6_addr_is_multicast(&fl.fl6_dst))
|
|
fl.oif = np->mcast_oif;
|
|
|
|
err = ip6_dst_lookup(sk, &dst, &fl);
|
|
if (err)
|
|
goto out;
|
|
|
|
/*
|
|
* We won't send icmp if the destination is known
|
|
* anycast.
|
|
*/
|
|
if (((struct rt6_info *)dst)->rt6i_flags & RTF_ANYCAST) {
|
|
LIMIT_NETDEBUG(KERN_DEBUG "icmpv6_send: acast source\n");
|
|
goto out_dst_release;
|
|
}
|
|
|
|
if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0)
|
|
goto out;
|
|
|
|
if (ipv6_addr_is_multicast(&fl.fl6_dst))
|
|
hlimit = np->mcast_hops;
|
|
else
|
|
hlimit = np->hop_limit;
|
|
if (hlimit < 0)
|
|
hlimit = dst_metric(dst, RTAX_HOPLIMIT);
|
|
if (hlimit < 0)
|
|
hlimit = ipv6_get_hoplimit(dst->dev);
|
|
|
|
tclass = np->cork.tclass;
|
|
if (tclass < 0)
|
|
tclass = 0;
|
|
|
|
msg.skb = skb;
|
|
msg.offset = skb->nh.raw - skb->data;
|
|
msg.type = type;
|
|
|
|
len = skb->len - msg.offset;
|
|
len = min_t(unsigned int, len, IPV6_MIN_MTU - sizeof(struct ipv6hdr) -sizeof(struct icmp6hdr));
|
|
if (len < 0) {
|
|
LIMIT_NETDEBUG(KERN_DEBUG "icmp: len problem\n");
|
|
goto out_dst_release;
|
|
}
|
|
|
|
idev = in6_dev_get(skb->dev);
|
|
|
|
err = ip6_append_data(sk, icmpv6_getfrag, &msg,
|
|
len + sizeof(struct icmp6hdr),
|
|
sizeof(struct icmp6hdr),
|
|
hlimit, tclass, NULL, &fl, (struct rt6_info*)dst,
|
|
MSG_DONTWAIT);
|
|
if (err) {
|
|
ip6_flush_pending_frames(sk);
|
|
goto out_put;
|
|
}
|
|
err = icmpv6_push_pending_frames(sk, &fl, &tmp_hdr, len + sizeof(struct icmp6hdr));
|
|
|
|
if (type >= ICMPV6_DEST_UNREACH && type <= ICMPV6_PARAMPROB)
|
|
ICMP6_INC_STATS_OFFSET_BH(idev, ICMP6_MIB_OUTDESTUNREACHS, type - ICMPV6_DEST_UNREACH);
|
|
ICMP6_INC_STATS_BH(idev, ICMP6_MIB_OUTMSGS);
|
|
|
|
out_put:
|
|
if (likely(idev != NULL))
|
|
in6_dev_put(idev);
|
|
out_dst_release:
|
|
dst_release(dst);
|
|
out:
|
|
icmpv6_xmit_unlock();
|
|
}
|
|
|
|
static void icmpv6_echo_reply(struct sk_buff *skb)
|
|
{
|
|
struct sock *sk;
|
|
struct inet6_dev *idev;
|
|
struct ipv6_pinfo *np;
|
|
struct in6_addr *saddr = NULL;
|
|
struct icmp6hdr *icmph = (struct icmp6hdr *) skb->h.raw;
|
|
struct icmp6hdr tmp_hdr;
|
|
struct flowi fl;
|
|
struct icmpv6_msg msg;
|
|
struct dst_entry *dst;
|
|
int err = 0;
|
|
int hlimit;
|
|
int tclass;
|
|
|
|
saddr = &skb->nh.ipv6h->daddr;
|
|
|
|
if (!ipv6_unicast_destination(skb))
|
|
saddr = NULL;
|
|
|
|
memcpy(&tmp_hdr, icmph, sizeof(tmp_hdr));
|
|
tmp_hdr.icmp6_type = ICMPV6_ECHO_REPLY;
|
|
|
|
memset(&fl, 0, sizeof(fl));
|
|
fl.proto = IPPROTO_ICMPV6;
|
|
ipv6_addr_copy(&fl.fl6_dst, &skb->nh.ipv6h->saddr);
|
|
if (saddr)
|
|
ipv6_addr_copy(&fl.fl6_src, saddr);
|
|
fl.oif = skb->dev->ifindex;
|
|
fl.fl_icmp_type = ICMPV6_ECHO_REPLY;
|
|
|
|
if (icmpv6_xmit_lock())
|
|
return;
|
|
|
|
sk = icmpv6_socket->sk;
|
|
np = inet6_sk(sk);
|
|
|
|
if (!fl.oif && ipv6_addr_is_multicast(&fl.fl6_dst))
|
|
fl.oif = np->mcast_oif;
|
|
|
|
err = ip6_dst_lookup(sk, &dst, &fl);
|
|
if (err)
|
|
goto out;
|
|
if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0)
|
|
goto out;
|
|
|
|
if (ipv6_addr_is_multicast(&fl.fl6_dst))
|
|
hlimit = np->mcast_hops;
|
|
else
|
|
hlimit = np->hop_limit;
|
|
if (hlimit < 0)
|
|
hlimit = dst_metric(dst, RTAX_HOPLIMIT);
|
|
if (hlimit < 0)
|
|
hlimit = ipv6_get_hoplimit(dst->dev);
|
|
|
|
tclass = np->cork.tclass;
|
|
if (tclass < 0)
|
|
tclass = 0;
|
|
|
|
idev = in6_dev_get(skb->dev);
|
|
|
|
msg.skb = skb;
|
|
msg.offset = 0;
|
|
msg.type = ICMPV6_ECHO_REPLY;
|
|
|
|
err = ip6_append_data(sk, icmpv6_getfrag, &msg, skb->len + sizeof(struct icmp6hdr),
|
|
sizeof(struct icmp6hdr), hlimit, tclass, NULL, &fl,
|
|
(struct rt6_info*)dst, MSG_DONTWAIT);
|
|
|
|
if (err) {
|
|
ip6_flush_pending_frames(sk);
|
|
goto out_put;
|
|
}
|
|
err = icmpv6_push_pending_frames(sk, &fl, &tmp_hdr, skb->len + sizeof(struct icmp6hdr));
|
|
|
|
ICMP6_INC_STATS_BH(idev, ICMP6_MIB_OUTECHOREPLIES);
|
|
ICMP6_INC_STATS_BH(idev, ICMP6_MIB_OUTMSGS);
|
|
|
|
out_put:
|
|
if (likely(idev != NULL))
|
|
in6_dev_put(idev);
|
|
dst_release(dst);
|
|
out:
|
|
icmpv6_xmit_unlock();
|
|
}
|
|
|
|
static void icmpv6_notify(struct sk_buff *skb, int type, int code, u32 info)
|
|
{
|
|
struct in6_addr *saddr, *daddr;
|
|
struct inet6_protocol *ipprot;
|
|
struct sock *sk;
|
|
int inner_offset;
|
|
int hash;
|
|
u8 nexthdr;
|
|
|
|
if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
|
|
return;
|
|
|
|
nexthdr = ((struct ipv6hdr *)skb->data)->nexthdr;
|
|
if (ipv6_ext_hdr(nexthdr)) {
|
|
/* now skip over extension headers */
|
|
inner_offset = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr);
|
|
if (inner_offset<0)
|
|
return;
|
|
} else {
|
|
inner_offset = sizeof(struct ipv6hdr);
|
|
}
|
|
|
|
/* Checkin header including 8 bytes of inner protocol header. */
|
|
if (!pskb_may_pull(skb, inner_offset+8))
|
|
return;
|
|
|
|
saddr = &skb->nh.ipv6h->saddr;
|
|
daddr = &skb->nh.ipv6h->daddr;
|
|
|
|
/* BUGGG_FUTURE: we should try to parse exthdrs in this packet.
|
|
Without this we will not able f.e. to make source routed
|
|
pmtu discovery.
|
|
Corresponding argument (opt) to notifiers is already added.
|
|
--ANK (980726)
|
|
*/
|
|
|
|
hash = nexthdr & (MAX_INET_PROTOS - 1);
|
|
|
|
rcu_read_lock();
|
|
ipprot = rcu_dereference(inet6_protos[hash]);
|
|
if (ipprot && ipprot->err_handler)
|
|
ipprot->err_handler(skb, NULL, type, code, inner_offset, info);
|
|
rcu_read_unlock();
|
|
|
|
read_lock(&raw_v6_lock);
|
|
if ((sk = sk_head(&raw_v6_htable[hash])) != NULL) {
|
|
while((sk = __raw_v6_lookup(sk, nexthdr, daddr, saddr,
|
|
IP6CB(skb)->iif))) {
|
|
rawv6_err(sk, skb, NULL, type, code, inner_offset, info);
|
|
sk = sk_next(sk);
|
|
}
|
|
}
|
|
read_unlock(&raw_v6_lock);
|
|
}
|
|
|
|
/*
|
|
* Handle icmp messages
|
|
*/
|
|
|
|
static int icmpv6_rcv(struct sk_buff **pskb)
|
|
{
|
|
struct sk_buff *skb = *pskb;
|
|
struct net_device *dev = skb->dev;
|
|
struct inet6_dev *idev = __in6_dev_get(dev);
|
|
struct in6_addr *saddr, *daddr;
|
|
struct ipv6hdr *orig_hdr;
|
|
struct icmp6hdr *hdr;
|
|
int type;
|
|
|
|
ICMP6_INC_STATS_BH(idev, ICMP6_MIB_INMSGS);
|
|
|
|
saddr = &skb->nh.ipv6h->saddr;
|
|
daddr = &skb->nh.ipv6h->daddr;
|
|
|
|
/* Perform checksum. */
|
|
switch (skb->ip_summed) {
|
|
case CHECKSUM_HW:
|
|
if (!csum_ipv6_magic(saddr, daddr, skb->len, IPPROTO_ICMPV6,
|
|
skb->csum))
|
|
break;
|
|
/* fall through */
|
|
case CHECKSUM_NONE:
|
|
skb->csum = ~csum_ipv6_magic(saddr, daddr, skb->len,
|
|
IPPROTO_ICMPV6, 0);
|
|
if (__skb_checksum_complete(skb)) {
|
|
LIMIT_NETDEBUG(KERN_DEBUG "ICMPv6 checksum failed [" NIP6_FMT " > " NIP6_FMT "]\n",
|
|
NIP6(*saddr), NIP6(*daddr));
|
|
goto discard_it;
|
|
}
|
|
}
|
|
|
|
if (!pskb_pull(skb, sizeof(struct icmp6hdr)))
|
|
goto discard_it;
|
|
|
|
hdr = (struct icmp6hdr *) skb->h.raw;
|
|
|
|
type = hdr->icmp6_type;
|
|
|
|
if (type >= ICMPV6_DEST_UNREACH && type <= ICMPV6_PARAMPROB)
|
|
ICMP6_INC_STATS_OFFSET_BH(idev, ICMP6_MIB_INDESTUNREACHS, type - ICMPV6_DEST_UNREACH);
|
|
else if (type >= ICMPV6_ECHO_REQUEST && type <= NDISC_REDIRECT)
|
|
ICMP6_INC_STATS_OFFSET_BH(idev, ICMP6_MIB_INECHOS, type - ICMPV6_ECHO_REQUEST);
|
|
|
|
switch (type) {
|
|
case ICMPV6_ECHO_REQUEST:
|
|
icmpv6_echo_reply(skb);
|
|
break;
|
|
|
|
case ICMPV6_ECHO_REPLY:
|
|
/* we couldn't care less */
|
|
break;
|
|
|
|
case ICMPV6_PKT_TOOBIG:
|
|
/* BUGGG_FUTURE: if packet contains rthdr, we cannot update
|
|
standard destination cache. Seems, only "advanced"
|
|
destination cache will allow to solve this problem
|
|
--ANK (980726)
|
|
*/
|
|
if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
|
|
goto discard_it;
|
|
hdr = (struct icmp6hdr *) skb->h.raw;
|
|
orig_hdr = (struct ipv6hdr *) (hdr + 1);
|
|
rt6_pmtu_discovery(&orig_hdr->daddr, &orig_hdr->saddr, dev,
|
|
ntohl(hdr->icmp6_mtu));
|
|
|
|
/*
|
|
* Drop through to notify
|
|
*/
|
|
|
|
case ICMPV6_DEST_UNREACH:
|
|
case ICMPV6_TIME_EXCEED:
|
|
case ICMPV6_PARAMPROB:
|
|
icmpv6_notify(skb, type, hdr->icmp6_code, hdr->icmp6_mtu);
|
|
break;
|
|
|
|
case NDISC_ROUTER_SOLICITATION:
|
|
case NDISC_ROUTER_ADVERTISEMENT:
|
|
case NDISC_NEIGHBOUR_SOLICITATION:
|
|
case NDISC_NEIGHBOUR_ADVERTISEMENT:
|
|
case NDISC_REDIRECT:
|
|
ndisc_rcv(skb);
|
|
break;
|
|
|
|
case ICMPV6_MGM_QUERY:
|
|
igmp6_event_query(skb);
|
|
break;
|
|
|
|
case ICMPV6_MGM_REPORT:
|
|
igmp6_event_report(skb);
|
|
break;
|
|
|
|
case ICMPV6_MGM_REDUCTION:
|
|
case ICMPV6_NI_QUERY:
|
|
case ICMPV6_NI_REPLY:
|
|
case ICMPV6_MLD2_REPORT:
|
|
case ICMPV6_DHAAD_REQUEST:
|
|
case ICMPV6_DHAAD_REPLY:
|
|
case ICMPV6_MOBILE_PREFIX_SOL:
|
|
case ICMPV6_MOBILE_PREFIX_ADV:
|
|
break;
|
|
|
|
default:
|
|
LIMIT_NETDEBUG(KERN_DEBUG "icmpv6: msg of unknown type\n");
|
|
|
|
/* informational */
|
|
if (type & ICMPV6_INFOMSG_MASK)
|
|
break;
|
|
|
|
/*
|
|
* error of unknown type.
|
|
* must pass to upper level
|
|
*/
|
|
|
|
icmpv6_notify(skb, type, hdr->icmp6_code, hdr->icmp6_mtu);
|
|
};
|
|
kfree_skb(skb);
|
|
return 0;
|
|
|
|
discard_it:
|
|
ICMP6_INC_STATS_BH(idev, ICMP6_MIB_INERRORS);
|
|
kfree_skb(skb);
|
|
return 0;
|
|
}
|
|
|
|
int __init icmpv6_init(struct net_proto_family *ops)
|
|
{
|
|
struct sock *sk;
|
|
int err, i, j;
|
|
|
|
for_each_cpu(i) {
|
|
err = sock_create_kern(PF_INET6, SOCK_RAW, IPPROTO_ICMPV6,
|
|
&per_cpu(__icmpv6_socket, i));
|
|
if (err < 0) {
|
|
printk(KERN_ERR
|
|
"Failed to initialize the ICMP6 control socket "
|
|
"(err %d).\n",
|
|
err);
|
|
goto fail;
|
|
}
|
|
|
|
sk = per_cpu(__icmpv6_socket, i)->sk;
|
|
sk->sk_allocation = GFP_ATOMIC;
|
|
|
|
/* Enough space for 2 64K ICMP packets, including
|
|
* sk_buff struct overhead.
|
|
*/
|
|
sk->sk_sndbuf =
|
|
(2 * ((64 * 1024) + sizeof(struct sk_buff)));
|
|
|
|
sk->sk_prot->unhash(sk);
|
|
}
|
|
|
|
|
|
if (inet6_add_protocol(&icmpv6_protocol, IPPROTO_ICMPV6) < 0) {
|
|
printk(KERN_ERR "Failed to register ICMP6 protocol\n");
|
|
err = -EAGAIN;
|
|
goto fail;
|
|
}
|
|
|
|
return 0;
|
|
|
|
fail:
|
|
for (j = 0; j < i; j++) {
|
|
if (!cpu_possible(j))
|
|
continue;
|
|
sock_release(per_cpu(__icmpv6_socket, j));
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
void icmpv6_cleanup(void)
|
|
{
|
|
int i;
|
|
|
|
for_each_cpu(i) {
|
|
sock_release(per_cpu(__icmpv6_socket, i));
|
|
}
|
|
inet6_del_protocol(&icmpv6_protocol, IPPROTO_ICMPV6);
|
|
}
|
|
|
|
static const struct icmp6_err {
|
|
int err;
|
|
int fatal;
|
|
} tab_unreach[] = {
|
|
{ /* NOROUTE */
|
|
.err = ENETUNREACH,
|
|
.fatal = 0,
|
|
},
|
|
{ /* ADM_PROHIBITED */
|
|
.err = EACCES,
|
|
.fatal = 1,
|
|
},
|
|
{ /* Was NOT_NEIGHBOUR, now reserved */
|
|
.err = EHOSTUNREACH,
|
|
.fatal = 0,
|
|
},
|
|
{ /* ADDR_UNREACH */
|
|
.err = EHOSTUNREACH,
|
|
.fatal = 0,
|
|
},
|
|
{ /* PORT_UNREACH */
|
|
.err = ECONNREFUSED,
|
|
.fatal = 1,
|
|
},
|
|
};
|
|
|
|
int icmpv6_err_convert(int type, int code, int *err)
|
|
{
|
|
int fatal = 0;
|
|
|
|
*err = EPROTO;
|
|
|
|
switch (type) {
|
|
case ICMPV6_DEST_UNREACH:
|
|
fatal = 1;
|
|
if (code <= ICMPV6_PORT_UNREACH) {
|
|
*err = tab_unreach[code].err;
|
|
fatal = tab_unreach[code].fatal;
|
|
}
|
|
break;
|
|
|
|
case ICMPV6_PKT_TOOBIG:
|
|
*err = EMSGSIZE;
|
|
break;
|
|
|
|
case ICMPV6_PARAMPROB:
|
|
*err = EPROTO;
|
|
fatal = 1;
|
|
break;
|
|
|
|
case ICMPV6_TIME_EXCEED:
|
|
*err = EHOSTUNREACH;
|
|
break;
|
|
};
|
|
|
|
return fatal;
|
|
}
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
ctl_table ipv6_icmp_table[] = {
|
|
{
|
|
.ctl_name = NET_IPV6_ICMP_RATELIMIT,
|
|
.procname = "ratelimit",
|
|
.data = &sysctl_icmpv6_time,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = &proc_dointvec
|
|
},
|
|
{ .ctl_name = 0 },
|
|
};
|
|
#endif
|
|
|
|
|