diff options
| -rw-r--r-- | include/linux/icmpv6.h | 3 | ||||
| -rw-r--r-- | include/uapi/linux/icmp.h | 1 | ||||
| -rw-r--r-- | net/ipv4/ip_gre.c | 5 | ||||
| -rw-r--r-- | net/ipv6/icmp.c | 28 | ||||
| -rw-r--r-- | net/ipv6/sit.c | 4 |
5 files changed, 34 insertions, 7 deletions
diff --git a/include/linux/icmpv6.h b/include/linux/icmpv6.h index 97ae98071a03..57086e9fc64c 100644 --- a/include/linux/icmpv6.h +++ b/include/linux/icmpv6.h @@ -18,7 +18,8 @@ typedef void ip6_icmp_send_t(struct sk_buff *skb, u8 type, u8 code, __u32 info, const struct in6_addr *force_saddr); extern int inet6_register_icmp_sender(ip6_icmp_send_t *fn); extern int inet6_unregister_icmp_sender(ip6_icmp_send_t *fn); -int ip6_err_gen_icmpv6_unreach(struct sk_buff *skb, int nhs, int type); +int ip6_err_gen_icmpv6_unreach(struct sk_buff *skb, int nhs, int type, + unsigned int data_len); #else diff --git a/include/uapi/linux/icmp.h b/include/uapi/linux/icmp.h index 16fff055f734..fddd9d736284 100644 --- a/include/uapi/linux/icmp.h +++ b/include/uapi/linux/icmp.h @@ -79,6 +79,7 @@ struct icmphdr { __be16 __unused; __be16 mtu; } frag; + __u8 reserved[4]; } un; }; diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index ab4cff8e563d..8eec78f53f9e 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -144,6 +144,7 @@ static void ipgre_err(struct sk_buff *skb, u32 info, const struct iphdr *iph; const int type = icmp_hdr(skb)->type; const int code = icmp_hdr(skb)->code; + unsigned int data_len = 0; struct ip_tunnel *t; switch (type) { @@ -169,6 +170,7 @@ static void ipgre_err(struct sk_buff *skb, u32 info, case ICMP_TIME_EXCEEDED: if (code != ICMP_EXC_TTL) return; + data_len = icmp_hdr(skb)->un.reserved[1] * 4; /* RFC 4884 4.1 */ break; case ICMP_REDIRECT: @@ -189,7 +191,8 @@ static void ipgre_err(struct sk_buff *skb, u32 info, #if IS_ENABLED(CONFIG_IPV6) if (tpi->proto == htons(ETH_P_IPV6) && - !ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4 + tpi->hdr_len, type)) + !ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4 + tpi->hdr_len, + type, data_len)) return; #endif diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c index 867aebc34248..fd11f5856ce8 100644 --- a/net/ipv6/icmp.c +++ b/net/ipv6/icmp.c @@ -564,16 +564,22 @@ void icmpv6_param_prob(struct sk_buff *skb, u8 code, int pos) * Either an IPv4 header for SIT encap * an IPv4 header + GRE header for GRE encap */ -int ip6_err_gen_icmpv6_unreach(struct sk_buff *skb, int nhs, int type) +int ip6_err_gen_icmpv6_unreach(struct sk_buff *skb, int nhs, int type, + unsigned int data_len) { struct in6_addr temp_saddr; struct rt6_info *rt; struct sk_buff *skb2; + u32 info = 0; if (!pskb_may_pull(skb, nhs + sizeof(struct ipv6hdr) + 8)) return 1; - skb2 = skb_clone(skb, GFP_ATOMIC); + /* RFC 4884 (partial) support for ICMP extensions */ + if (data_len < 128 || (data_len & 7) || skb->len < data_len) + data_len = 0; + + skb2 = data_len ? skb_copy(skb, GFP_ATOMIC) : skb_clone(skb, GFP_ATOMIC); if (!skb2) return 1; @@ -588,12 +594,26 @@ int ip6_err_gen_icmpv6_unreach(struct sk_buff *skb, int nhs, int type) skb2->dev = rt->dst.dev; ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr, &temp_saddr); + + if (data_len) { + /* RFC 4884 (partial) support : + * insert 0 padding at the end, before the extensions + */ + __skb_push(skb2, nhs); + skb_reset_network_header(skb2); + memmove(skb2->data, skb2->data + nhs, data_len - nhs); + memset(skb2->data + data_len - nhs, 0, nhs); + /* RFC 4884 4.5 : Length is measured in 64-bit words, + * and stored in reserved[0] + */ + info = (data_len/8) << 24; + } if (type == ICMP_TIME_EXCEEDED) icmp6_send(skb2, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, - 0, &temp_saddr); + info, &temp_saddr); else icmp6_send(skb2, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, - 0, &temp_saddr); + info, &temp_saddr); if (rt) ip6_rt_put(rt); diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c index d7a36114eb50..cdd714690f95 100644 --- a/net/ipv6/sit.c +++ b/net/ipv6/sit.c @@ -484,6 +484,7 @@ static int ipip6_err(struct sk_buff *skb, u32 info) const struct iphdr *iph = (const struct iphdr *)skb->data; const int type = icmp_hdr(skb)->type; const int code = icmp_hdr(skb)->code; + unsigned int data_len = 0; struct ip_tunnel *t; int err; @@ -508,6 +509,7 @@ static int ipip6_err(struct sk_buff *skb, u32 info) case ICMP_TIME_EXCEEDED: if (code != ICMP_EXC_TTL) return 0; + data_len = icmp_hdr(skb)->un.reserved[1] * 4; /* RFC 4884 4.1 */ break; case ICMP_REDIRECT: break; @@ -536,7 +538,7 @@ static int ipip6_err(struct sk_buff *skb, u32 info) } err = 0; - if (!ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4, type)) + if (!ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4, type, data_len)) goto out; if (t->parms.iph.daddr == 0) |