diff options
| author | Stephen Hemminger <shemminger@vyatta.com> | 2010-04-22 15:24:53 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2010-04-22 15:24:53 -0700 |
| commit | e802af9cabb011f09b9c19a82faef3dd315f27eb (patch) | |
| tree | 9a8ef1163b9b40fef8860b08ea4dcb4ff3916098 /net | |
| parent | 9ccb8975940c4ee51161152e37058e3d9e06c62f (diff) | |
IPv6: Generic TTL Security Mechanism (final version)
This patch adds IPv6 support for RFC5082 Generalized TTL Security Mechanism.
Not to users of mapped address; the IPV6 and IPV4 socket options are seperate.
The server does have to deal with both IPv4 and IPv6 socket options
and the client has to handle the different for each family.
On client:
int ttl = 255;
getaddrinfo(argv[1], argv[2], &hint, &result);
for (rp = result; rp != NULL; rp = rp->ai_next) {
s = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
if (s < 0) continue;
if (rp->ai_family == AF_INET) {
setsockopt(s, IPPROTO_IP, IP_TTL, &ttl, sizeof(ttl));
} else if (rp->ai_family == AF_INET6) {
setsockopt(s, IPPROTO_IPV6, IPV6_UNICAST_HOPS,
&ttl, sizeof(ttl)))
}
if (connect(s, rp->ai_addr, rp->ai_addrlen) == 0) {
...
On server:
int minttl = 255 - maxhops;
getaddrinfo(NULL, port, &hints, &result);
for (rp = result; rp != NULL; rp = rp->ai_next) {
s = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
if (s < 0) continue;
if (rp->ai_family == AF_INET6)
setsockopt(s, IPPROTO_IPV6, IPV6_MINHOPCOUNT,
&minttl, sizeof(minttl));
setsockopt(s, IPPROTO_IP, IP_MINTTL, &minttl, sizeof(minttl));
if (bind(s, rp->ai_addr, rp->ai_addrlen) == 0)
break
...
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv6/ipv6_sockglue.c | 12 | ||||
| -rw-r--r-- | net/ipv6/tcp_ipv6.c | 14 |
2 files changed, 25 insertions, 1 deletions
diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index 1160400e9db..92295ad3487 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 1ababbb4113..6603511e367 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; |