diff options
| -rw-r--r-- | include/linux/in6.h | 3 | ||||
| -rw-r--r-- | include/linux/ipv6.h | 1 | ||||
| -rw-r--r-- | net/ipv6/ipv6_sockglue.c | 12 | ||||
| -rw-r--r-- | net/ipv6/tcp_ipv6.c | 14 |
4 files changed, 29 insertions, 1 deletions
diff --git a/include/linux/in6.h b/include/linux/in6.h index bd55c6e46b2e..9b90cb296eb1 100644 --- a/include/linux/in6.h +++ b/include/linux/in6.h @@ -265,6 +265,9 @@ struct in6_flowlabel_req { #define IPV6_PREFER_SRC_CGA 0x0008 #define IPV6_PREFER_SRC_NONCGA 0x0800 +/* RFC5082: Generalized Ttl Security Mechanism */ +#define IPV6_MINHOPCOUNT 73 + /* * Multicast Routing: * see include/linux/mroute6.h. diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h index e0cc9a7db2b5..1bdbebf08d16 100644 --- a/include/linux/ipv6.h +++ b/include/linux/ipv6.h @@ -348,6 +348,7 @@ struct ipv6_pinfo { * 010: prefer public address * 100: prefer care-of address */ + __u8 min_hopcount; __u8 tclass; __u32 dst_cookie; diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index 1160400e9dbd..92295ad3487a 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -767,6 +767,14 @@ pref_skip_coa: break; } + case IPV6_MINHOPCOUNT: + if (optlen < sizeof(int)) + goto e_inval; + if (val < 0 || val > 255) + goto e_inval; + np->min_hopcount = val; + retv = 0; + break; } release_sock(sk); @@ -1116,6 +1124,10 @@ static int do_ipv6_getsockopt(struct sock *sk, int level, int optname, val |= IPV6_PREFER_SRC_HOME; break; + case IPV6_MINHOPCOUNT: + val = np->min_hopcount; + break; + default: return -ENOPROTOOPT; } diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 1ababbb41131..6603511e3673 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -353,6 +353,11 @@ static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, if (sk->sk_state == TCP_CLOSE) goto out; + if (ipv6_hdr(skb)->hop_limit < inet6_sk(sk)->min_hopcount) { + NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP); + goto out; + } + tp = tcp_sk(sk); seq = ntohl(th->seq); if (sk->sk_state != TCP_LISTEN && @@ -1678,6 +1683,7 @@ ipv6_pktoptions: static int tcp_v6_rcv(struct sk_buff *skb) { struct tcphdr *th; + struct ipv6hdr *hdr; struct sock *sk; int ret; struct net *net = dev_net(skb->dev); @@ -1704,12 +1710,13 @@ static int tcp_v6_rcv(struct sk_buff *skb) goto bad_packet; th = tcp_hdr(skb); + hdr = ipv6_hdr(skb); TCP_SKB_CB(skb)->seq = ntohl(th->seq); TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + skb->len - th->doff*4); TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); TCP_SKB_CB(skb)->when = 0; - TCP_SKB_CB(skb)->flags = ipv6_get_dsfield(ipv6_hdr(skb)); + TCP_SKB_CB(skb)->flags = ipv6_get_dsfield(hdr); TCP_SKB_CB(skb)->sacked = 0; sk = __inet6_lookup_skb(&tcp_hashinfo, skb, th->source, th->dest); @@ -1720,6 +1727,11 @@ process: if (sk->sk_state == TCP_TIME_WAIT) goto do_time_wait; + if (hdr->hop_limit < inet6_sk(sk)->min_hopcount) { + NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP); + goto discard_and_relse; + } + if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) goto discard_and_relse; |