[ 005/143] ipvs: fix CHECKSUM_PARTIAL for TCP, UDP

Willy Tarreau
2014-05-12T01:41:26Z

From: Julian Anastasov <ja@ssi.bg>

Fix CHECKSUM_PARTIAL handling. Tested for IPv4 TCP,
UDP not tested because it needs network card with HW CSUM support.
May be fixes problem where IPVS can not be used in virtual boxes.
Problem appears with DNAT to local address when the local stack
sends reply in CHECKSUM_PARTIAL mode.

Fix tcp_dnat_handler and udp_dnat_handler to provide
vaddr and daddr in right order (old and new IP) when calling
tcp_partial_csum_update/udp_partial_csum_update (CHECKSUM_PARTIAL).

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
(cherry picked from commit 5bc9068e9d962ca6b8bec3f0eb6f60ab4dee1d04)
Signed-off-by: Willy Tarreau <w@1wt.eu>
---
net/netfilter/ipvs/ip_vs_proto_tcp.c | 10 +++++-----
net/netfilter/ipvs/ip_vs_proto_udp.c | 10 +++++-----
2 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/net/netfilter/ipvs/ip_vs_proto_tcp.c b/net/netfilter/ipvs/ip_vs_proto_tcp.c
index 91d28e0..d462b0d 100644
--- a/net/netfilter/ipvs/ip_vs_proto_tcp.c
+++ b/net/netfilter/ipvs/ip_vs_proto_tcp.c
@@ -147,15 +147,15 @@ tcp_partial_csum_update(int af, struct tcphdr *tcph,
#ifdef CONFIG_IP_VS_IPV6
if (af == AF_INET6)
tcph->check =
- csum_fold(ip_vs_check_diff16(oldip->ip6, newip->ip6,
+ ~csum_fold(ip_vs_check_diff16(oldip->ip6, newip->ip6,
ip_vs_check_diff2(oldlen, newlen,
- ~csum_unfold(tcph->check))));
+ csum_unfold(tcph->check))));
else
#endif
tcph->check =
- csum_fold(ip_vs_check_diff4(oldip->ip, newip->ip,
+ ~csum_fold(ip_vs_check_diff4(oldip->ip, newip->ip,
ip_vs_check_diff2(oldlen, newlen,
- ~csum_unfold(tcph->check))));
+ csum_unfold(tcph->check))));
}

@@ -269,7 +269,7 @@ tcp_dnat_handler(struct sk_buff *skb,
* Adjust TCP checksums
*/
if (skb->ip_summed == CHECKSUM_PARTIAL) {
- tcp_partial_csum_update(cp->af, tcph, &cp->daddr, &cp->vaddr,
+ tcp_partial_csum_update(cp->af, tcph, &cp->vaddr, &cp->daddr,
htons(oldlen),
htons(skb->len - tcphoff));
} else if (!cp->app) {
diff --git a/net/netfilter/ipvs/ip_vs_proto_udp.c b/net/netfilter/ipvs/ip_vs_proto_udp.c
index e7a6885..c1781f5 100644
--- a/net/netfilter/ipvs/ip_vs_proto_udp.c
+++ b/net/netfilter/ipvs/ip_vs_proto_udp.c
@@ -154,15 +154,15 @@ udp_partial_csum_update(int af, struct udphdr *uhdr,
#ifdef CONFIG_IP_VS_IPV6
if (af == AF_INET6)
uhdr->check =
- csum_fold(ip_vs_check_diff16(oldip->ip6, newip->ip6,
+ ~csum_fold(ip_vs_check_diff16(oldip->ip6, newip->ip6,
ip_vs_check_diff2(oldlen, newlen,
- ~csum_unfold(uhdr->check))));
+ csum_unfold(uhdr->check))));
else
#endif
uhdr->check =
- csum_fold(ip_vs_check_diff4(oldip->ip, newip->ip,
+ ~csum_fold(ip_vs_check_diff4(oldip->ip, newip->ip,
ip_vs_check_diff2(oldlen, newlen,
- ~csum_unfold(uhdr->check))));
+ csum_unfold(uhdr->check))));
}

@@ -205,7 +205,7 @@ udp_snat_handler(struct sk_buff *skb,
* Adjust UDP checksums
*/
if (skb->ip_summed == CHECKSUM_PARTIAL) {
- udp_partial_csum_update(cp->af, udph, &cp->daddr, &cp->vaddr,
+ udp_partial_csum_update(cp->af, udph, &cp->vaddr, &cp->daddr,
htons(oldlen),
htons(skb->len - udphoff));
} else if (!cp->app && (udph->check != 0)) {
--
1.7.12.2.21.g234cd45.dirty