diff options
author | Kim Kibum <kb0929.kim@samsung.com> | 2012-04-29 16:59:19 +0900 |
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committer | Kim Kibum <kb0929.kim@samsung.com> | 2012-04-29 16:59:19 +0900 |
commit | c1775d1a93a77a57380a4ce87ac3a8f807c944b2 (patch) | |
tree | e1f233f2af38ee247a677082198dd3a69a12a5a1 /net/ipv6/icmp.c | |
parent | 2c2dcd5ffef2e97176e6a55e45512177e55e6fb9 (diff) | |
download | linux-2.6.36-c1775d1a93a77a57380a4ce87ac3a8f807c944b2.tar.gz linux-2.6.36-c1775d1a93a77a57380a4ce87ac3a8f807c944b2.tar.bz2 linux-2.6.36-c1775d1a93a77a57380a4ce87ac3a8f807c944b2.zip |
Diffstat (limited to 'net/ipv6/icmp.c')
-rw-r--r-- | net/ipv6/icmp.c | 966 |
1 files changed, 966 insertions, 0 deletions
diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c new file mode 100644 index 00000000..03e62f94 --- /dev/null +++ b/net/ipv6/icmp.c @@ -0,0 +1,966 @@ +/* + * Internet Control Message Protocol (ICMPv6) + * Linux INET6 implementation + * + * Authors: + * Pedro Roque <roque@di.fc.ul.pt> + * + * 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/sockios.h> +#include <linux/net.h> +#include <linux/skbuff.h> +#include <linux/init.h> +#include <linux/netfilter.h> +#include <linux/slab.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 <net/xfrm.h> +#include <net/inet_common.h> + +#include <asm/uaccess.h> +#include <asm/system.h> + +/* + * 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 inline struct sock *icmpv6_sk(struct net *net) +{ + return net->ipv6.icmp_sk[smp_processor_id()]; +} + +static int icmpv6_rcv(struct sk_buff *skb); + +static const struct inet6_protocol icmpv6_protocol = { + .handler = icmpv6_rcv, + .flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, +}; + +static __inline__ struct sock *icmpv6_xmit_lock(struct net *net) +{ + struct sock *sk; + + local_bh_disable(); + + sk = icmpv6_sk(net); + if (unlikely(!spin_trylock(&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 NULL; + } + return sk; +} + +static __inline__ void icmpv6_xmit_unlock(struct sock *sk) +{ + spin_unlock_bh(&sk->sk_lock.slock); +} + +/* + * Slightly more convenient version of icmpv6_send. + */ +void icmpv6_param_prob(struct sk_buff *skb, u8 code, int pos) +{ + icmpv6_send(skb, ICMPV6_PARAMPROB, code, pos); + 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 *)(ipv6_hdr(skb) + 1) - skb->data; + int len = skb->len - ptr; + __u8 nexthdr = ipv6_hdr(skb)->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; +} + +/* + * Check the ICMP output rate limit + */ +static inline int icmpv6_xrlim_allow(struct sock *sk, u8 type, + struct flowi *fl) +{ + struct dst_entry *dst; + struct net *net = sock_net(sk); + 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(net, sk, fl); + if (dst->error) { + IP6_INC_STATS(net, ip6_dst_idev(dst), + 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 = net->ipv6.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_network_offset(skb); + 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 = icmp6_hdr(skb); + memcpy(icmp6h, thdr, sizeof(struct icmp6hdr)); + icmp6h->icmp6_cksum = 0; + + if (skb_queue_len(&sk->sk_write_queue) == 1) { + skb->csum = csum_partial(icmp6h, + sizeof(struct icmp6hdr), skb->csum); + icmp6h->icmp6_cksum = csum_ipv6_magic(&fl->fl6_src, + &fl->fl6_dst, + len, fl->proto, + skb->csum); + } else { + __wsum tmp_csum = 0; + + skb_queue_walk(&sk->sk_write_queue, skb) { + tmp_csum = csum_add(tmp_csum, skb->csum); + } + + tmp_csum = csum_partial(icmp6h, + sizeof(struct icmp6hdr), tmp_csum); + icmp6h->icmp6_cksum = csum_ipv6_magic(&fl->fl6_src, + &fl->fl6_dst, + len, fl->proto, + tmp_csum); + } + 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; + __wsum 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; +} + +#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) +static void mip6_addr_swap(struct sk_buff *skb) +{ + struct ipv6hdr *iph = ipv6_hdr(skb); + struct inet6_skb_parm *opt = IP6CB(skb); + struct ipv6_destopt_hao *hao; + struct in6_addr tmp; + int off; + + if (opt->dsthao) { + off = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO); + if (likely(off >= 0)) { + hao = (struct ipv6_destopt_hao *) + (skb_network_header(skb) + off); + ipv6_addr_copy(&tmp, &iph->saddr); + ipv6_addr_copy(&iph->saddr, &hao->addr); + ipv6_addr_copy(&hao->addr, &tmp); + } + } +} +#else +static inline void mip6_addr_swap(struct sk_buff *skb) {} +#endif + +/* + * Send an ICMP message in response to a packet in error + */ +void icmpv6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info) +{ + struct net *net = dev_net(skb->dev); + struct inet6_dev *idev = NULL; + struct ipv6hdr *hdr = ipv6_hdr(skb); + struct sock *sk; + struct ipv6_pinfo *np; + struct in6_addr *saddr = NULL; + struct dst_entry *dst; + struct dst_entry *dst2; + struct icmp6hdr tmp_hdr; + struct flowi fl; + struct flowi fl2; + struct icmpv6_msg msg; + int iif = 0; + int addr_type = 0; + int len; + int hlimit; + int err = 0; + + if ((u8 *)hdr < skb->head || + (skb->network_header + sizeof(*hdr)) > 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(net, &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; + } + + mip6_addr_swap(skb); + + 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; + security_skb_classify_flow(skb, &fl); + + sk = icmpv6_xmit_lock(net); + if (sk == NULL) + return; + 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; + } + + /* No need to clone since we're just using its address. */ + dst2 = dst; + + err = xfrm_lookup(net, &dst, &fl, sk, 0); + switch (err) { + case 0: + if (dst != dst2) + goto route_done; + break; + case -EPERM: + dst = NULL; + break; + default: + goto out; + } + + if (xfrm_decode_session_reverse(skb, &fl2, AF_INET6)) + goto relookup_failed; + + if (ip6_dst_lookup(sk, &dst2, &fl2)) + goto relookup_failed; + + err = xfrm_lookup(net, &dst2, &fl2, sk, XFRM_LOOKUP_ICMP); + switch (err) { + case 0: + dst_release(dst); + dst = dst2; + break; + case -EPERM: + goto out_dst_release; + default: +relookup_failed: + if (!dst) + goto out; + break; + } + +route_done: + if (ipv6_addr_is_multicast(&fl.fl6_dst)) + 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; + } + + 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, &fl, (struct rt6_info*)dst, + MSG_DONTWAIT, np->dontfrag); + if (err) { + ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_OUTERRORS); + ip6_flush_pending_frames(sk); + goto out_put; + } + err = icmpv6_push_pending_frames(sk, &fl, &tmp_hdr, len + sizeof(struct icmp6hdr)); + +out_put: + if (likely(idev != NULL)) + in6_dev_put(idev); +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; + struct in6_addr *saddr = NULL; + struct icmp6hdr *icmph = icmp6_hdr(skb); + struct icmp6hdr tmp_hdr; + struct flowi fl; + 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(&fl, 0, sizeof(fl)); + fl.proto = IPPROTO_ICMPV6; + ipv6_addr_copy(&fl.fl6_dst, &ipv6_hdr(skb)->saddr); + if (saddr) + ipv6_addr_copy(&fl.fl6_src, saddr); + fl.oif = skb->dev->ifindex; + fl.fl_icmp_type = ICMPV6_ECHO_REPLY; + security_skb_classify_flow(skb, &fl); + + sk = icmpv6_xmit_lock(net); + if (sk == NULL) + return; + 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(net, &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 = 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, &fl, + (struct rt6_info*)dst, MSG_DONTWAIT, + np->dontfrag); + + if (err) { + ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_OUTERRORS); + ip6_flush_pending_frames(sk); + goto out_put; + } + err = icmpv6_push_pending_frames(sk, &fl, &tmp_hdr, skb->len + sizeof(struct icmp6hdr)); + +out_put: + if (likely(idev != NULL)) + in6_dev_put(idev); + 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); + struct in6_addr *saddr, *daddr; + 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 flowi *fl, + u8 type, + const struct in6_addr *saddr, + const struct in6_addr *daddr, + int oif) +{ + memset(fl, 0, sizeof(*fl)); + ipv6_addr_copy(&fl->fl6_src, saddr); + ipv6_addr_copy(&fl->fl6_dst, daddr); + fl->proto = IPPROTO_ICMPV6; + fl->fl_icmp_type = type; + fl->fl_icmp_code = 0; + fl->oif = oif; + security_sk_classify_flow(sk, fl); +} + +/* + * 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 * ((64 * 1024) + sizeof(struct sk_buff))); + } + 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 + |