diff options
author | Stanislav Fomichev <stfomichev@yandex-team.ru> | 2013-10-22 16:43:23 +0400 |
---|---|---|
committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2013-10-23 11:20:00 +0200 |
commit | f2020b27be94222eb25c39ff46eb9917cb92897b (patch) | |
tree | c95066079a1cc1df42935b0c275e78eb9ec6aaee /net/ipv6 | |
parent | 1a869205c75cb222263fa04f200485ffbe9eaadf (diff) |
netfilter: ip6t_REJECT: skip checksum verification for outgoing ipv6 packets
Don't verify checksum for outgoing packets because checksum calculation
may be done by the device.
Without this patch:
$ ip6tables -I OUTPUT -p tcp --dport 80 -j REJECT --reject-with tcp-reset
$ time telnet ipv6.google.com 80
Trying 2a00:1450:4010:c03::67...
telnet: Unable to connect to remote host: Connection timed out
real 0m7.201s
user 0m0.000s
sys 0m0.000s
With the patch applied:
$ ip6tables -I OUTPUT -p tcp --dport 80 -j REJECT --reject-with tcp-reset
$ time telnet ipv6.google.com 80
Trying 2a00:1450:4010:c03::67...
telnet: Unable to connect to remote host: Connection refused
real 0m0.085s
user 0m0.000s
sys 0m0.000s
Signed-off-by: Stanislav Fomichev <stfomichev@yandex-team.ru>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/ipv6')
-rw-r--r-- | net/ipv6/netfilter/ip6t_REJECT.c | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/net/ipv6/netfilter/ip6t_REJECT.c b/net/ipv6/netfilter/ip6t_REJECT.c index 56eef30ee5f6..da00a2ecde55 100644 --- a/net/ipv6/netfilter/ip6t_REJECT.c +++ b/net/ipv6/netfilter/ip6t_REJECT.c @@ -39,7 +39,7 @@ MODULE_DESCRIPTION("Xtables: packet \"rejection\" target for IPv6"); MODULE_LICENSE("GPL"); /* Send RST reply */ -static void send_reset(struct net *net, struct sk_buff *oldskb) +static void send_reset(struct net *net, struct sk_buff *oldskb, int hook) { struct sk_buff *nskb; struct tcphdr otcph, *tcph; @@ -88,8 +88,7 @@ static void send_reset(struct net *net, struct sk_buff *oldskb) } /* Check checksum. */ - if (csum_ipv6_magic(&oip6h->saddr, &oip6h->daddr, otcplen, IPPROTO_TCP, - skb_checksum(oldskb, tcphoff, otcplen, 0))) { + if (nf_ip6_checksum(oldskb, hook, tcphoff, IPPROTO_TCP)) { pr_debug("TCP checksum is invalid\n"); return; } @@ -227,7 +226,7 @@ reject_tg6(struct sk_buff *skb, const struct xt_action_param *par) /* Do nothing */ break; case IP6T_TCP_RESET: - send_reset(net, skb); + send_reset(net, skb, par->hooknum); break; default: net_info_ratelimited("case %u not handled yet\n", reject->with); |