mirror of https://gitee.com/openkylin/linux.git
977 lines
22 KiB
C
977 lines
22 KiB
C
/*
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* Internet Control Message Protocol (ICMPv6)
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* Linux INET6 implementation
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*
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* Authors:
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* Pedro Roque <roque@di.fc.ul.pt>
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*
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* Based on net/ipv4/icmp.c
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*
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* RFC 1885
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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/*
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* Changes:
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*
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* Andi Kleen : exception handling
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* Andi Kleen add rate limits. never reply to a icmp.
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* add more length checks and other fixes.
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* yoshfuji : ensure to sent parameter problem for
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* fragments.
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* YOSHIFUJI Hideaki @USAGI: added sysctl for icmp rate limit.
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* Randy Dunlap and
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* YOSHIFUJI Hideaki @USAGI: Per-interface statistics support
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* Kazunori MIYAZAWA @USAGI: change output process to use ip6_append_data
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*/
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#include <linux/module.h>
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#include <linux/errno.h>
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#include <linux/types.h>
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#include <linux/socket.h>
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#include <linux/in.h>
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#include <linux/kernel.h>
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#include <linux/sockios.h>
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#include <linux/net.h>
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#include <linux/skbuff.h>
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#include <linux/init.h>
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#include <linux/netfilter.h>
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#include <linux/slab.h>
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#ifdef CONFIG_SYSCTL
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#include <linux/sysctl.h>
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#endif
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#include <linux/inet.h>
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#include <linux/netdevice.h>
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#include <linux/icmpv6.h>
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#include <net/ip.h>
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#include <net/sock.h>
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#include <net/ipv6.h>
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#include <net/ip6_checksum.h>
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#include <net/protocol.h>
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#include <net/raw.h>
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#include <net/rawv6.h>
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#include <net/transp_v6.h>
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#include <net/ip6_route.h>
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#include <net/addrconf.h>
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#include <net/icmp.h>
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#include <net/xfrm.h>
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#include <net/inet_common.h>
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#include <asm/uaccess.h>
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#include <asm/system.h>
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/*
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* The ICMP socket(s). This is the most convenient way to flow control
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* our ICMP output as well as maintain a clean interface throughout
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* all layers. All Socketless IP sends will soon be gone.
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*
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* On SMP we have one ICMP socket per-cpu.
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*/
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static inline struct sock *icmpv6_sk(struct net *net)
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{
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return net->ipv6.icmp_sk[smp_processor_id()];
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}
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static int icmpv6_rcv(struct sk_buff *skb);
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static const struct inet6_protocol icmpv6_protocol = {
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.handler = icmpv6_rcv,
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.flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
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};
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static __inline__ struct sock *icmpv6_xmit_lock(struct net *net)
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{
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struct sock *sk;
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local_bh_disable();
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sk = icmpv6_sk(net);
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if (unlikely(!spin_trylock(&sk->sk_lock.slock))) {
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/* This can happen if the output path (f.e. SIT or
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* ip6ip6 tunnel) signals dst_link_failure() for an
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* outgoing ICMP6 packet.
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*/
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local_bh_enable();
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return NULL;
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}
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return sk;
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}
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static __inline__ void icmpv6_xmit_unlock(struct sock *sk)
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{
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spin_unlock_bh(&sk->sk_lock.slock);
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}
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/*
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* Slightly more convenient version of icmpv6_send.
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*/
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void icmpv6_param_prob(struct sk_buff *skb, u8 code, int pos)
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{
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icmpv6_send(skb, ICMPV6_PARAMPROB, code, pos);
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kfree_skb(skb);
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}
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/*
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* Figure out, may we reply to this packet with icmp error.
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*
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* We do not reply, if:
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* - it was icmp error message.
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* - it is truncated, so that it is known, that protocol is ICMPV6
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* (i.e. in the middle of some exthdr)
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*
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* --ANK (980726)
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*/
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static int is_ineligible(struct sk_buff *skb)
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{
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int ptr = (u8 *)(ipv6_hdr(skb) + 1) - skb->data;
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int len = skb->len - ptr;
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__u8 nexthdr = ipv6_hdr(skb)->nexthdr;
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if (len < 0)
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return 1;
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ptr = ipv6_skip_exthdr(skb, ptr, &nexthdr);
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if (ptr < 0)
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return 0;
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if (nexthdr == IPPROTO_ICMPV6) {
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u8 _type, *tp;
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tp = skb_header_pointer(skb,
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ptr+offsetof(struct icmp6hdr, icmp6_type),
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sizeof(_type), &_type);
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if (tp == NULL ||
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!(*tp & ICMPV6_INFOMSG_MASK))
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return 1;
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}
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return 0;
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}
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/*
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* Check the ICMP output rate limit
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*/
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static inline bool icmpv6_xrlim_allow(struct sock *sk, u8 type,
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struct flowi6 *fl6)
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{
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struct dst_entry *dst;
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struct net *net = sock_net(sk);
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bool res = false;
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/* Informational messages are not limited. */
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if (type & ICMPV6_INFOMSG_MASK)
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return true;
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/* Do not limit pmtu discovery, it would break it. */
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if (type == ICMPV6_PKT_TOOBIG)
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return true;
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/*
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* Look up the output route.
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* XXX: perhaps the expire for routing entries cloned by
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* this lookup should be more aggressive (not longer than timeout).
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*/
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dst = ip6_route_output(net, sk, fl6);
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if (dst->error) {
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IP6_INC_STATS(net, ip6_dst_idev(dst),
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IPSTATS_MIB_OUTNOROUTES);
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} else if (dst->dev && (dst->dev->flags&IFF_LOOPBACK)) {
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res = true;
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} else {
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struct rt6_info *rt = (struct rt6_info *)dst;
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int tmo = net->ipv6.sysctl.icmpv6_time;
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/* Give more bandwidth to wider prefixes. */
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if (rt->rt6i_dst.plen < 128)
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tmo >>= ((128 - rt->rt6i_dst.plen)>>5);
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if (!rt->rt6i_peer)
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rt6_bind_peer(rt, 1);
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res = inet_peer_xrlim_allow(rt->rt6i_peer, tmo);
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}
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dst_release(dst);
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return res;
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}
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/*
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* an inline helper for the "simple" if statement below
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* checks if parameter problem report is caused by an
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* unrecognized IPv6 option that has the Option Type
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* highest-order two bits set to 10
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*/
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static __inline__ int opt_unrec(struct sk_buff *skb, __u32 offset)
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{
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u8 _optval, *op;
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offset += skb_network_offset(skb);
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op = skb_header_pointer(skb, offset, sizeof(_optval), &_optval);
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if (op == NULL)
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return 1;
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return (*op & 0xC0) == 0x80;
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}
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static int icmpv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6, struct icmp6hdr *thdr, int len)
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{
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struct sk_buff *skb;
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struct icmp6hdr *icmp6h;
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int err = 0;
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if ((skb = skb_peek(&sk->sk_write_queue)) == NULL)
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goto out;
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icmp6h = icmp6_hdr(skb);
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memcpy(icmp6h, thdr, sizeof(struct icmp6hdr));
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icmp6h->icmp6_cksum = 0;
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if (skb_queue_len(&sk->sk_write_queue) == 1) {
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skb->csum = csum_partial(icmp6h,
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sizeof(struct icmp6hdr), skb->csum);
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icmp6h->icmp6_cksum = csum_ipv6_magic(&fl6->saddr,
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&fl6->daddr,
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len, fl6->flowi6_proto,
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skb->csum);
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} else {
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__wsum tmp_csum = 0;
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skb_queue_walk(&sk->sk_write_queue, skb) {
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tmp_csum = csum_add(tmp_csum, skb->csum);
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}
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tmp_csum = csum_partial(icmp6h,
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sizeof(struct icmp6hdr), tmp_csum);
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icmp6h->icmp6_cksum = csum_ipv6_magic(&fl6->saddr,
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&fl6->daddr,
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len, fl6->flowi6_proto,
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tmp_csum);
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}
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ip6_push_pending_frames(sk);
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out:
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return err;
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}
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struct icmpv6_msg {
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struct sk_buff *skb;
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int offset;
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uint8_t type;
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};
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static int icmpv6_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb)
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{
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struct icmpv6_msg *msg = (struct icmpv6_msg *) from;
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struct sk_buff *org_skb = msg->skb;
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__wsum csum = 0;
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csum = skb_copy_and_csum_bits(org_skb, msg->offset + offset,
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to, len, csum);
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skb->csum = csum_block_add(skb->csum, csum, odd);
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if (!(msg->type & ICMPV6_INFOMSG_MASK))
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nf_ct_attach(skb, org_skb);
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return 0;
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}
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#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
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static void mip6_addr_swap(struct sk_buff *skb)
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{
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struct ipv6hdr *iph = ipv6_hdr(skb);
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struct inet6_skb_parm *opt = IP6CB(skb);
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struct ipv6_destopt_hao *hao;
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struct in6_addr tmp;
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int off;
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if (opt->dsthao) {
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off = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
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if (likely(off >= 0)) {
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hao = (struct ipv6_destopt_hao *)
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(skb_network_header(skb) + off);
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ipv6_addr_copy(&tmp, &iph->saddr);
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ipv6_addr_copy(&iph->saddr, &hao->addr);
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ipv6_addr_copy(&hao->addr, &tmp);
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}
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}
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}
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#else
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static inline void mip6_addr_swap(struct sk_buff *skb) {}
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#endif
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static struct dst_entry *icmpv6_route_lookup(struct net *net, struct sk_buff *skb,
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struct sock *sk, struct flowi6 *fl6)
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{
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struct dst_entry *dst, *dst2;
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struct flowi6 fl2;
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int err;
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err = ip6_dst_lookup(sk, &dst, fl6);
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if (err)
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return ERR_PTR(err);
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|
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/*
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* We won't send icmp if the destination is known
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* anycast.
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*/
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if (((struct rt6_info *)dst)->rt6i_flags & RTF_ANYCAST) {
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LIMIT_NETDEBUG(KERN_DEBUG "icmpv6_send: acast source\n");
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dst_release(dst);
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return ERR_PTR(-EINVAL);
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}
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|
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/* No need to clone since we're just using its address. */
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dst2 = dst;
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|
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dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), sk, 0);
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if (!IS_ERR(dst)) {
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if (dst != dst2)
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return dst;
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} else {
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if (PTR_ERR(dst) == -EPERM)
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dst = NULL;
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else
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return dst;
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}
|
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|
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err = xfrm_decode_session_reverse(skb, flowi6_to_flowi(&fl2), AF_INET6);
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if (err)
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goto relookup_failed;
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|
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err = ip6_dst_lookup(sk, &dst2, &fl2);
|
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if (err)
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goto relookup_failed;
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|
|
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dst2 = xfrm_lookup(net, dst2, flowi6_to_flowi(&fl2), sk, XFRM_LOOKUP_ICMP);
|
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if (!IS_ERR(dst2)) {
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dst_release(dst);
|
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dst = dst2;
|
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} else {
|
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err = PTR_ERR(dst2);
|
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if (err == -EPERM) {
|
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dst_release(dst);
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return dst2;
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} else
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goto relookup_failed;
|
|
}
|
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|
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relookup_failed:
|
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if (dst)
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return dst;
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return ERR_PTR(err);
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}
|
|
|
|
/*
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* Send an ICMP message in response to a packet in error
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*/
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void icmpv6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info)
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{
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struct net *net = dev_net(skb->dev);
|
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struct inet6_dev *idev = NULL;
|
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struct ipv6hdr *hdr = ipv6_hdr(skb);
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struct sock *sk;
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struct ipv6_pinfo *np;
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const struct in6_addr *saddr = NULL;
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struct dst_entry *dst;
|
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struct icmp6hdr tmp_hdr;
|
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struct flowi6 fl6;
|
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struct icmpv6_msg msg;
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int iif = 0;
|
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int addr_type = 0;
|
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int len;
|
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int hlimit;
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int err = 0;
|
|
|
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if ((u8 *)hdr < skb->head ||
|
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(skb->network_header + sizeof(*hdr)) > skb->tail)
|
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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.
|
|
*/
|
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addr_type = ipv6_addr_type(&hdr->daddr);
|
|
|
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if (ipv6_chk_addr(net, &hdr->daddr, skb->dev, 0))
|
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saddr = &hdr->daddr;
|
|
|
|
/*
|
|
* Dest addr check
|
|
*/
|
|
|
|
if ((addr_type & IPV6_ADDR_MULTICAST || skb->pkt_type != PACKET_HOST)) {
|
|
if (type != ICMPV6_PKT_TOOBIG &&
|
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!(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;
|
|
}
|
|
|
|
mip6_addr_swap(skb);
|
|
|
|
memset(&fl6, 0, sizeof(fl6));
|
|
fl6.flowi6_proto = IPPROTO_ICMPV6;
|
|
ipv6_addr_copy(&fl6.daddr, &hdr->saddr);
|
|
if (saddr)
|
|
ipv6_addr_copy(&fl6.saddr, saddr);
|
|
fl6.flowi6_oif = iif;
|
|
fl6.fl6_icmp_type = type;
|
|
fl6.fl6_icmp_code = code;
|
|
security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));
|
|
|
|
sk = icmpv6_xmit_lock(net);
|
|
if (sk == NULL)
|
|
return;
|
|
np = inet6_sk(sk);
|
|
|
|
if (!icmpv6_xrlim_allow(sk, type, &fl6))
|
|
goto out;
|
|
|
|
tmp_hdr.icmp6_type = type;
|
|
tmp_hdr.icmp6_code = code;
|
|
tmp_hdr.icmp6_cksum = 0;
|
|
tmp_hdr.icmp6_pointer = htonl(info);
|
|
|
|
if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
|
|
fl6.flowi6_oif = np->mcast_oif;
|
|
|
|
dst = icmpv6_route_lookup(net, skb, sk, &fl6);
|
|
if (IS_ERR(dst))
|
|
goto out;
|
|
|
|
if (ipv6_addr_is_multicast(&fl6.daddr))
|
|
hlimit = np->mcast_hops;
|
|
else
|
|
hlimit = np->hop_limit;
|
|
if (hlimit < 0)
|
|
hlimit = ip6_dst_hoplimit(dst);
|
|
|
|
msg.skb = skb;
|
|
msg.offset = skb_network_offset(skb);
|
|
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;
|
|
}
|
|
|
|
rcu_read_lock();
|
|
idev = __in6_dev_get(skb->dev);
|
|
|
|
err = ip6_append_data(sk, icmpv6_getfrag, &msg,
|
|
len + sizeof(struct icmp6hdr),
|
|
sizeof(struct icmp6hdr), hlimit,
|
|
np->tclass, NULL, &fl6, (struct rt6_info*)dst,
|
|
MSG_DONTWAIT, np->dontfrag);
|
|
if (err) {
|
|
ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_OUTERRORS);
|
|
ip6_flush_pending_frames(sk);
|
|
} else {
|
|
err = icmpv6_push_pending_frames(sk, &fl6, &tmp_hdr,
|
|
len + sizeof(struct icmp6hdr));
|
|
}
|
|
rcu_read_unlock();
|
|
out_dst_release:
|
|
dst_release(dst);
|
|
out:
|
|
icmpv6_xmit_unlock(sk);
|
|
}
|
|
EXPORT_SYMBOL(icmpv6_send);
|
|
|
|
static void icmpv6_echo_reply(struct sk_buff *skb)
|
|
{
|
|
struct net *net = dev_net(skb->dev);
|
|
struct sock *sk;
|
|
struct inet6_dev *idev;
|
|
struct ipv6_pinfo *np;
|
|
const struct in6_addr *saddr = NULL;
|
|
struct icmp6hdr *icmph = icmp6_hdr(skb);
|
|
struct icmp6hdr tmp_hdr;
|
|
struct flowi6 fl6;
|
|
struct icmpv6_msg msg;
|
|
struct dst_entry *dst;
|
|
int err = 0;
|
|
int hlimit;
|
|
|
|
saddr = &ipv6_hdr(skb)->daddr;
|
|
|
|
if (!ipv6_unicast_destination(skb))
|
|
saddr = NULL;
|
|
|
|
memcpy(&tmp_hdr, icmph, sizeof(tmp_hdr));
|
|
tmp_hdr.icmp6_type = ICMPV6_ECHO_REPLY;
|
|
|
|
memset(&fl6, 0, sizeof(fl6));
|
|
fl6.flowi6_proto = IPPROTO_ICMPV6;
|
|
ipv6_addr_copy(&fl6.daddr, &ipv6_hdr(skb)->saddr);
|
|
if (saddr)
|
|
ipv6_addr_copy(&fl6.saddr, saddr);
|
|
fl6.flowi6_oif = skb->dev->ifindex;
|
|
fl6.fl6_icmp_type = ICMPV6_ECHO_REPLY;
|
|
security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));
|
|
|
|
sk = icmpv6_xmit_lock(net);
|
|
if (sk == NULL)
|
|
return;
|
|
np = inet6_sk(sk);
|
|
|
|
if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
|
|
fl6.flowi6_oif = np->mcast_oif;
|
|
|
|
err = ip6_dst_lookup(sk, &dst, &fl6);
|
|
if (err)
|
|
goto out;
|
|
dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), sk, 0);
|
|
if (IS_ERR(dst))
|
|
goto out;
|
|
|
|
if (ipv6_addr_is_multicast(&fl6.daddr))
|
|
hlimit = np->mcast_hops;
|
|
else
|
|
hlimit = np->hop_limit;
|
|
if (hlimit < 0)
|
|
hlimit = ip6_dst_hoplimit(dst);
|
|
|
|
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, np->tclass, NULL, &fl6,
|
|
(struct rt6_info*)dst, MSG_DONTWAIT,
|
|
np->dontfrag);
|
|
|
|
if (err) {
|
|
ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_OUTERRORS);
|
|
ip6_flush_pending_frames(sk);
|
|
} else {
|
|
err = icmpv6_push_pending_frames(sk, &fl6, &tmp_hdr,
|
|
skb->len + sizeof(struct icmp6hdr));
|
|
}
|
|
dst_release(dst);
|
|
out:
|
|
icmpv6_xmit_unlock(sk);
|
|
}
|
|
|
|
static void icmpv6_notify(struct sk_buff *skb, u8 type, u8 code, __be32 info)
|
|
{
|
|
const struct inet6_protocol *ipprot;
|
|
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;
|
|
|
|
/* 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();
|
|
|
|
raw6_icmp_error(skb, nexthdr, type, code, inner_offset, info);
|
|
}
|
|
|
|
/*
|
|
* Handle icmp messages
|
|
*/
|
|
|
|
static int icmpv6_rcv(struct sk_buff *skb)
|
|
{
|
|
struct net_device *dev = skb->dev;
|
|
struct inet6_dev *idev = __in6_dev_get(dev);
|
|
const struct in6_addr *saddr, *daddr;
|
|
const struct ipv6hdr *orig_hdr;
|
|
struct icmp6hdr *hdr;
|
|
u8 type;
|
|
|
|
if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
|
|
struct sec_path *sp = skb_sec_path(skb);
|
|
int nh;
|
|
|
|
if (!(sp && sp->xvec[sp->len - 1]->props.flags &
|
|
XFRM_STATE_ICMP))
|
|
goto drop_no_count;
|
|
|
|
if (!pskb_may_pull(skb, sizeof(*hdr) + sizeof(*orig_hdr)))
|
|
goto drop_no_count;
|
|
|
|
nh = skb_network_offset(skb);
|
|
skb_set_network_header(skb, sizeof(*hdr));
|
|
|
|
if (!xfrm6_policy_check_reverse(NULL, XFRM_POLICY_IN, skb))
|
|
goto drop_no_count;
|
|
|
|
skb_set_network_header(skb, nh);
|
|
}
|
|
|
|
ICMP6_INC_STATS_BH(dev_net(dev), idev, ICMP6_MIB_INMSGS);
|
|
|
|
saddr = &ipv6_hdr(skb)->saddr;
|
|
daddr = &ipv6_hdr(skb)->daddr;
|
|
|
|
/* Perform checksum. */
|
|
switch (skb->ip_summed) {
|
|
case CHECKSUM_COMPLETE:
|
|
if (!csum_ipv6_magic(saddr, daddr, skb->len, IPPROTO_ICMPV6,
|
|
skb->csum))
|
|
break;
|
|
/* fall through */
|
|
case CHECKSUM_NONE:
|
|
skb->csum = ~csum_unfold(csum_ipv6_magic(saddr, daddr, skb->len,
|
|
IPPROTO_ICMPV6, 0));
|
|
if (__skb_checksum_complete(skb)) {
|
|
LIMIT_NETDEBUG(KERN_DEBUG "ICMPv6 checksum failed [%pI6 > %pI6]\n",
|
|
saddr, daddr);
|
|
goto discard_it;
|
|
}
|
|
}
|
|
|
|
if (!pskb_pull(skb, sizeof(*hdr)))
|
|
goto discard_it;
|
|
|
|
hdr = icmp6_hdr(skb);
|
|
|
|
type = hdr->icmp6_type;
|
|
|
|
ICMP6MSGIN_INC_STATS_BH(dev_net(dev), idev, type);
|
|
|
|
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 = icmp6_hdr(skb);
|
|
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(dev_net(dev), idev, ICMP6_MIB_INERRORS);
|
|
drop_no_count:
|
|
kfree_skb(skb);
|
|
return 0;
|
|
}
|
|
|
|
void icmpv6_flow_init(struct sock *sk, struct flowi6 *fl6,
|
|
u8 type,
|
|
const struct in6_addr *saddr,
|
|
const struct in6_addr *daddr,
|
|
int oif)
|
|
{
|
|
memset(fl6, 0, sizeof(*fl6));
|
|
ipv6_addr_copy(&fl6->saddr, saddr);
|
|
ipv6_addr_copy(&fl6->daddr, daddr);
|
|
fl6->flowi6_proto = IPPROTO_ICMPV6;
|
|
fl6->fl6_icmp_type = type;
|
|
fl6->fl6_icmp_code = 0;
|
|
fl6->flowi6_oif = oif;
|
|
security_sk_classify_flow(sk, flowi6_to_flowi(fl6));
|
|
}
|
|
|
|
/*
|
|
* Special lock-class for __icmpv6_sk:
|
|
*/
|
|
static struct lock_class_key icmpv6_socket_sk_dst_lock_key;
|
|
|
|
static int __net_init icmpv6_sk_init(struct net *net)
|
|
{
|
|
struct sock *sk;
|
|
int err, i, j;
|
|
|
|
net->ipv6.icmp_sk =
|
|
kzalloc(nr_cpu_ids * sizeof(struct sock *), GFP_KERNEL);
|
|
if (net->ipv6.icmp_sk == NULL)
|
|
return -ENOMEM;
|
|
|
|
for_each_possible_cpu(i) {
|
|
err = inet_ctl_sock_create(&sk, PF_INET6,
|
|
SOCK_RAW, IPPROTO_ICMPV6, net);
|
|
if (err < 0) {
|
|
printk(KERN_ERR
|
|
"Failed to initialize the ICMP6 control socket "
|
|
"(err %d).\n",
|
|
err);
|
|
goto fail;
|
|
}
|
|
|
|
net->ipv6.icmp_sk[i] = sk;
|
|
|
|
/*
|
|
* Split off their lock-class, because sk->sk_dst_lock
|
|
* gets used from softirqs, which is safe for
|
|
* __icmpv6_sk (because those never get directly used
|
|
* via userspace syscalls), but unsafe for normal sockets.
|
|
*/
|
|
lockdep_set_class(&sk->sk_dst_lock,
|
|
&icmpv6_socket_sk_dst_lock_key);
|
|
|
|
/* Enough space for 2 64K ICMP packets, including
|
|
* sk_buff struct overhead.
|
|
*/
|
|
sk->sk_sndbuf = 2 * SKB_TRUESIZE(64 * 1024);
|
|
}
|
|
return 0;
|
|
|
|
fail:
|
|
for (j = 0; j < i; j++)
|
|
inet_ctl_sock_destroy(net->ipv6.icmp_sk[j]);
|
|
kfree(net->ipv6.icmp_sk);
|
|
return err;
|
|
}
|
|
|
|
static void __net_exit icmpv6_sk_exit(struct net *net)
|
|
{
|
|
int i;
|
|
|
|
for_each_possible_cpu(i) {
|
|
inet_ctl_sock_destroy(net->ipv6.icmp_sk[i]);
|
|
}
|
|
kfree(net->ipv6.icmp_sk);
|
|
}
|
|
|
|
static struct pernet_operations icmpv6_sk_ops = {
|
|
.init = icmpv6_sk_init,
|
|
.exit = icmpv6_sk_exit,
|
|
};
|
|
|
|
int __init icmpv6_init(void)
|
|
{
|
|
int err;
|
|
|
|
err = register_pernet_subsys(&icmpv6_sk_ops);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
err = -EAGAIN;
|
|
if (inet6_add_protocol(&icmpv6_protocol, IPPROTO_ICMPV6) < 0)
|
|
goto fail;
|
|
return 0;
|
|
|
|
fail:
|
|
printk(KERN_ERR "Failed to register ICMP6 protocol\n");
|
|
unregister_pernet_subsys(&icmpv6_sk_ops);
|
|
return err;
|
|
}
|
|
|
|
void icmpv6_cleanup(void)
|
|
{
|
|
unregister_pernet_subsys(&icmpv6_sk_ops);
|
|
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(u8 type, u8 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;
|
|
}
|
|
|
|
EXPORT_SYMBOL(icmpv6_err_convert);
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
ctl_table ipv6_icmp_table_template[] = {
|
|
{
|
|
.procname = "ratelimit",
|
|
.data = &init_net.ipv6.sysctl.icmpv6_time,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_ms_jiffies,
|
|
},
|
|
{ },
|
|
};
|
|
|
|
struct ctl_table * __net_init ipv6_icmp_sysctl_init(struct net *net)
|
|
{
|
|
struct ctl_table *table;
|
|
|
|
table = kmemdup(ipv6_icmp_table_template,
|
|
sizeof(ipv6_icmp_table_template),
|
|
GFP_KERNEL);
|
|
|
|
if (table)
|
|
table[0].data = &net->ipv6.sysctl.icmpv6_time;
|
|
|
|
return table;
|
|
}
|
|
#endif
|
|
|