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-rw-r--r--include/linux/netfilter.h6
-rw-r--r--include/linux/netfilter_ipv4/ip_nat.h4
-rw-r--r--include/linux/netfilter_ipv4/ip_nat_core.h8
-rw-r--r--net/ipv4/netfilter/ip_nat_core.c52
-rw-r--r--net/ipv4/netfilter/ip_nat_helper.c59
-rw-r--r--net/ipv4/netfilter/ip_nat_proto_gre.c5
-rw-r--r--net/ipv4/netfilter/ip_nat_proto_icmp.c8
-rw-r--r--net/ipv4/netfilter/ip_nat_proto_tcp.c7
-rw-r--r--net/ipv4/netfilter/ip_nat_proto_udp.c15
-rw-r--r--net/ipv4/netfilter/ip_nat_standalone.c10
-rw-r--r--net/ipv4/netfilter/ipt_ECN.c19
-rw-r--r--net/ipv4/netfilter/ipt_REJECT.c1
-rw-r--r--net/ipv4/netfilter/ipt_TCPMSS.c39
-rw-r--r--net/netfilter/core.c22
14 files changed, 138 insertions, 117 deletions
diff --git a/include/linux/netfilter.h b/include/linux/netfilter.h
index 10168e26a846..b7e67d1d4382 100644
--- a/include/linux/netfilter.h
+++ b/include/linux/netfilter.h
@@ -282,6 +282,12 @@ extern void nf_invalidate_cache(int pf);
Returns true or false. */
extern int skb_make_writable(struct sk_buff **pskb, unsigned int writable_len);
+extern u_int16_t nf_csum_update(u_int32_t oldval, u_int32_t newval,
+ u_int32_t csum);
+extern u_int16_t nf_proto_csum_update(struct sk_buff *skb,
+ u_int32_t oldval, u_int32_t newval,
+ u_int16_t csum, int pseudohdr);
+
struct nf_afinfo {
unsigned short family;
unsigned int (*checksum)(struct sk_buff *skb, unsigned int hook,
diff --git a/include/linux/netfilter_ipv4/ip_nat.h b/include/linux/netfilter_ipv4/ip_nat.h
index e9f5ed1d9f68..98f8407e4cb5 100644
--- a/include/linux/netfilter_ipv4/ip_nat.h
+++ b/include/linux/netfilter_ipv4/ip_nat.h
@@ -72,10 +72,6 @@ extern unsigned int ip_nat_setup_info(struct ip_conntrack *conntrack,
extern int ip_nat_used_tuple(const struct ip_conntrack_tuple *tuple,
const struct ip_conntrack *ignored_conntrack);
-/* Calculate relative checksum. */
-extern u_int16_t ip_nat_cheat_check(u_int32_t oldvalinv,
- u_int32_t newval,
- u_int16_t oldcheck);
#else /* !__KERNEL__: iptables wants this to compile. */
#define ip_nat_multi_range ip_nat_multi_range_compat
#endif /*__KERNEL__*/
diff --git a/include/linux/netfilter_ipv4/ip_nat_core.h b/include/linux/netfilter_ipv4/ip_nat_core.h
index 30db23f06b03..60566f9fd7b3 100644
--- a/include/linux/netfilter_ipv4/ip_nat_core.h
+++ b/include/linux/netfilter_ipv4/ip_nat_core.h
@@ -11,8 +11,8 @@ extern unsigned int ip_nat_packet(struct ip_conntrack *ct,
unsigned int hooknum,
struct sk_buff **pskb);
-extern int ip_nat_icmp_reply_translation(struct sk_buff **pskb,
- struct ip_conntrack *ct,
- enum ip_nat_manip_type manip,
- enum ip_conntrack_dir dir);
+extern int ip_nat_icmp_reply_translation(struct ip_conntrack *ct,
+ enum ip_conntrack_info ctinfo,
+ unsigned int hooknum,
+ struct sk_buff **pskb);
#endif /* _IP_NAT_CORE_H */
diff --git a/net/ipv4/netfilter/ip_nat_core.c b/net/ipv4/netfilter/ip_nat_core.c
index 1741d555ad0d..4c540d03d48e 100644
--- a/net/ipv4/netfilter/ip_nat_core.c
+++ b/net/ipv4/netfilter/ip_nat_core.c
@@ -101,18 +101,6 @@ static void ip_nat_cleanup_conntrack(struct ip_conntrack *conn)
write_unlock_bh(&ip_nat_lock);
}
-/* We do checksum mangling, so if they were wrong before they're still
- * wrong. Also works for incomplete packets (eg. ICMP dest
- * unreachables.) */
-u_int16_t
-ip_nat_cheat_check(u_int32_t oldvalinv, u_int32_t newval, u_int16_t oldcheck)
-{
- u_int32_t diffs[] = { oldvalinv, newval };
- return csum_fold(csum_partial((char *)diffs, sizeof(diffs),
- oldcheck^0xFFFF));
-}
-EXPORT_SYMBOL(ip_nat_cheat_check);
-
/* Is this tuple already taken? (not by us) */
int
ip_nat_used_tuple(const struct ip_conntrack_tuple *tuple,
@@ -378,12 +366,12 @@ manip_pkt(u_int16_t proto,
iph = (void *)(*pskb)->data + iphdroff;
if (maniptype == IP_NAT_MANIP_SRC) {
- iph->check = ip_nat_cheat_check(~iph->saddr, target->src.ip,
- iph->check);
+ iph->check = nf_csum_update(~iph->saddr, target->src.ip,
+ iph->check);
iph->saddr = target->src.ip;
} else {
- iph->check = ip_nat_cheat_check(~iph->daddr, target->dst.ip,
- iph->check);
+ iph->check = nf_csum_update(~iph->daddr, target->dst.ip,
+ iph->check);
iph->daddr = target->dst.ip;
}
return 1;
@@ -423,10 +411,10 @@ unsigned int ip_nat_packet(struct ip_conntrack *ct,
EXPORT_SYMBOL_GPL(ip_nat_packet);
/* Dir is direction ICMP is coming from (opposite to packet it contains) */
-int ip_nat_icmp_reply_translation(struct sk_buff **pskb,
- struct ip_conntrack *ct,
- enum ip_nat_manip_type manip,
- enum ip_conntrack_dir dir)
+int ip_nat_icmp_reply_translation(struct ip_conntrack *ct,
+ enum ip_conntrack_info ctinfo,
+ unsigned int hooknum,
+ struct sk_buff **pskb)
{
struct {
struct icmphdr icmp;
@@ -434,7 +422,9 @@ int ip_nat_icmp_reply_translation(struct sk_buff **pskb,
} *inside;
struct ip_conntrack_tuple inner, target;
int hdrlen = (*pskb)->nh.iph->ihl * 4;
+ enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
unsigned long statusbit;
+ enum ip_nat_manip_type manip = HOOK2MANIP(hooknum);
if (!skb_make_writable(pskb, hdrlen + sizeof(*inside)))
return 0;
@@ -443,12 +433,8 @@ int ip_nat_icmp_reply_translation(struct sk_buff **pskb,
/* We're actually going to mangle it beyond trivial checksum
adjustment, so make sure the current checksum is correct. */
- if ((*pskb)->ip_summed != CHECKSUM_UNNECESSARY) {
- hdrlen = (*pskb)->nh.iph->ihl * 4;
- if ((u16)csum_fold(skb_checksum(*pskb, hdrlen,
- (*pskb)->len - hdrlen, 0)))
- return 0;
- }
+ if (nf_ip_checksum(*pskb, hooknum, hdrlen, 0))
+ return 0;
/* Must be RELATED */
IP_NF_ASSERT((*pskb)->nfctinfo == IP_CT_RELATED ||
@@ -487,12 +473,14 @@ int ip_nat_icmp_reply_translation(struct sk_buff **pskb,
!manip))
return 0;
- /* Reloading "inside" here since manip_pkt inner. */
- inside = (void *)(*pskb)->data + (*pskb)->nh.iph->ihl*4;
- inside->icmp.checksum = 0;
- inside->icmp.checksum = csum_fold(skb_checksum(*pskb, hdrlen,
- (*pskb)->len - hdrlen,
- 0));
+ if ((*pskb)->ip_summed != CHECKSUM_PARTIAL) {
+ /* Reloading "inside" here since manip_pkt inner. */
+ inside = (void *)(*pskb)->data + (*pskb)->nh.iph->ihl*4;
+ inside->icmp.checksum = 0;
+ inside->icmp.checksum = csum_fold(skb_checksum(*pskb, hdrlen,
+ (*pskb)->len - hdrlen,
+ 0));
+ }
/* Change outer to look the reply to an incoming packet
* (proto 0 means don't invert per-proto part). */
diff --git a/net/ipv4/netfilter/ip_nat_helper.c b/net/ipv4/netfilter/ip_nat_helper.c
index cbcaa45370ae..021c3daae3ed 100644
--- a/net/ipv4/netfilter/ip_nat_helper.c
+++ b/net/ipv4/netfilter/ip_nat_helper.c
@@ -165,7 +165,7 @@ ip_nat_mangle_tcp_packet(struct sk_buff **pskb,
{
struct iphdr *iph;
struct tcphdr *tcph;
- int datalen;
+ int oldlen, datalen;
if (!skb_make_writable(pskb, (*pskb)->len))
return 0;
@@ -180,13 +180,22 @@ ip_nat_mangle_tcp_packet(struct sk_buff **pskb,
iph = (*pskb)->nh.iph;
tcph = (void *)iph + iph->ihl*4;
+ oldlen = (*pskb)->len - iph->ihl*4;
mangle_contents(*pskb, iph->ihl*4 + tcph->doff*4,
match_offset, match_len, rep_buffer, rep_len);
datalen = (*pskb)->len - iph->ihl*4;
- tcph->check = 0;
- tcph->check = tcp_v4_check(tcph, datalen, iph->saddr, iph->daddr,
- csum_partial((char *)tcph, datalen, 0));
+ if ((*pskb)->ip_summed != CHECKSUM_PARTIAL) {
+ tcph->check = 0;
+ tcph->check = tcp_v4_check(tcph, datalen,
+ iph->saddr, iph->daddr,
+ csum_partial((char *)tcph,
+ datalen, 0));
+ } else
+ tcph->check = nf_proto_csum_update(*pskb,
+ htons(oldlen) ^ 0xFFFF,
+ htons(datalen),
+ tcph->check, 1);
if (rep_len != match_len) {
set_bit(IPS_SEQ_ADJUST_BIT, &ct->status);
@@ -221,6 +230,7 @@ ip_nat_mangle_udp_packet(struct sk_buff **pskb,
{
struct iphdr *iph;
struct udphdr *udph;
+ int datalen, oldlen;
/* UDP helpers might accidentally mangle the wrong packet */
iph = (*pskb)->nh.iph;
@@ -238,22 +248,32 @@ ip_nat_mangle_udp_packet(struct sk_buff **pskb,
iph = (*pskb)->nh.iph;
udph = (void *)iph + iph->ihl*4;
+
+ oldlen = (*pskb)->len - iph->ihl*4;
mangle_contents(*pskb, iph->ihl*4 + sizeof(*udph),
match_offset, match_len, rep_buffer, rep_len);
/* update the length of the UDP packet */
- udph->len = htons((*pskb)->len - iph->ihl*4);
+ datalen = (*pskb)->len - iph->ihl*4;
+ udph->len = htons(datalen);
/* fix udp checksum if udp checksum was previously calculated */
- if (udph->check) {
- int datalen = (*pskb)->len - iph->ihl * 4;
+ if (!udph->check && (*pskb)->ip_summed != CHECKSUM_PARTIAL)
+ return 1;
+
+ if ((*pskb)->ip_summed != CHECKSUM_PARTIAL) {
udph->check = 0;
udph->check = csum_tcpudp_magic(iph->saddr, iph->daddr,
datalen, IPPROTO_UDP,
csum_partial((char *)udph,
datalen, 0));
- }
-
+ if (!udph->check)
+ udph->check = -1;
+ } else
+ udph->check = nf_proto_csum_update(*pskb,
+ htons(oldlen) ^ 0xFFFF,
+ htons(datalen),
+ udph->check, 1);
return 1;
}
EXPORT_SYMBOL(ip_nat_mangle_udp_packet);
@@ -293,11 +313,14 @@ sack_adjust(struct sk_buff *skb,
ntohl(sack->start_seq), new_start_seq,
ntohl(sack->end_seq), new_end_seq);
- tcph->check =
- ip_nat_cheat_check(~sack->start_seq, new_start_seq,
- ip_nat_cheat_check(~sack->end_seq,
- new_end_seq,
- tcph->check));
+ tcph->check = nf_proto_csum_update(skb,
+ ~sack->start_seq,
+ new_start_seq,
+ tcph->check, 0);
+ tcph->check = nf_proto_csum_update(skb,
+ ~sack->end_seq,
+ new_end_seq,
+ tcph->check, 0);
sack->start_seq = new_start_seq;
sack->end_seq = new_end_seq;
sackoff += sizeof(*sack);
@@ -381,10 +404,10 @@ ip_nat_seq_adjust(struct sk_buff **pskb,
newack = ntohl(tcph->ack_seq) - other_way->offset_before;
newack = htonl(newack);
- tcph->check = ip_nat_cheat_check(~tcph->seq, newseq,
- ip_nat_cheat_check(~tcph->ack_seq,
- newack,
- tcph->check));
+ tcph->check = nf_proto_csum_update(*pskb, ~tcph->seq, newseq,
+ tcph->check, 0);
+ tcph->check = nf_proto_csum_update(*pskb, ~tcph->ack_seq, newack,
+ tcph->check, 0);
DEBUGP("Adjusting sequence number from %u->%u, ack from %u->%u\n",
ntohl(tcph->seq), ntohl(newseq), ntohl(tcph->ack_seq),
diff --git a/net/ipv4/netfilter/ip_nat_proto_gre.c b/net/ipv4/netfilter/ip_nat_proto_gre.c
index 38acfdf540eb..70a65372225a 100644
--- a/net/ipv4/netfilter/ip_nat_proto_gre.c
+++ b/net/ipv4/netfilter/ip_nat_proto_gre.c
@@ -130,9 +130,10 @@ gre_manip_pkt(struct sk_buff **pskb,
if (greh->csum) {
/* FIXME: Never tested this code... */
*(gre_csum(greh)) =
- ip_nat_cheat_check(~*(gre_key(greh)),
+ nf_proto_csum_update(*pskb,
+ ~*(gre_key(greh)),
tuple->dst.u.gre.key,
- *(gre_csum(greh)));
+ *(gre_csum(greh)), 0);
}
*(gre_key(greh)) = tuple->dst.u.gre.key;
break;
diff --git a/net/ipv4/netfilter/ip_nat_proto_icmp.c b/net/ipv4/netfilter/ip_nat_proto_icmp.c
index 31a3f4ccb99c..ec50cc295317 100644
--- a/net/ipv4/netfilter/ip_nat_proto_icmp.c
+++ b/net/ipv4/netfilter/ip_nat_proto_icmp.c
@@ -66,10 +66,10 @@ icmp_manip_pkt(struct sk_buff **pskb,
return 0;
hdr = (struct icmphdr *)((*pskb)->data + hdroff);
-
- hdr->checksum = ip_nat_cheat_check(hdr->un.echo.id ^ 0xFFFF,
- tuple->src.u.icmp.id,
- hdr->checksum);
+ hdr->checksum = nf_proto_csum_update(*pskb,
+ hdr->un.echo.id ^ 0xFFFF,
+ tuple->src.u.icmp.id,
+ hdr->checksum, 0);
hdr->un.echo.id = tuple->src.u.icmp.id;
return 1;
}
diff --git a/net/ipv4/netfilter/ip_nat_proto_tcp.c b/net/ipv4/netfilter/ip_nat_proto_tcp.c
index a3d14079eba6..72a6307bd2db 100644
--- a/net/ipv4/netfilter/ip_nat_proto_tcp.c
+++ b/net/ipv4/netfilter/ip_nat_proto_tcp.c
@@ -129,10 +129,9 @@ tcp_manip_pkt(struct sk_buff **pskb,
if (hdrsize < sizeof(*hdr))
return 1;
- hdr->check = ip_nat_cheat_check(~oldip, newip,
- ip_nat_cheat_check(oldport ^ 0xFFFF,
- newport,
- hdr->check));
+ hdr->check = nf_proto_csum_update(*pskb, ~oldip, newip, hdr->check, 1);
+ hdr->check = nf_proto_csum_update(*pskb, oldport ^ 0xFFFF, newport,
+ hdr->check, 0);
return 1;
}
diff --git a/net/ipv4/netfilter/ip_nat_proto_udp.c b/net/ipv4/netfilter/ip_nat_proto_udp.c
index ec6053fdc867..5da196ae758c 100644
--- a/net/ipv4/netfilter/ip_nat_proto_udp.c
+++ b/net/ipv4/netfilter/ip_nat_proto_udp.c
@@ -113,11 +113,16 @@ udp_manip_pkt(struct sk_buff **pskb,
newport = tuple->dst.u.udp.port;
portptr = &hdr->dest;
}
- if (hdr->check) /* 0 is a special case meaning no checksum */
- hdr->check = ip_nat_cheat_check(~oldip, newip,
- ip_nat_cheat_check(*portptr ^ 0xFFFF,
- newport,
- hdr->check));
+
+ if (hdr->check || (*pskb)->ip_summed == CHECKSUM_PARTIAL) {
+ hdr->check = nf_proto_csum_update(*pskb, ~oldip, newip,
+ hdr->check, 1);
+ hdr->check = nf_proto_csum_update(*pskb,
+ *portptr ^ 0xFFFF, newport,
+ hdr->check, 0);
+ if (!hdr->check)
+ hdr->check = -1;
+ }
*portptr = newport;
return 1;
}
diff --git a/net/ipv4/netfilter/ip_nat_standalone.c b/net/ipv4/netfilter/ip_nat_standalone.c
index f4f00c816d87..f3b778355432 100644
--- a/net/ipv4/netfilter/ip_nat_standalone.c
+++ b/net/ipv4/netfilter/ip_nat_standalone.c
@@ -110,12 +110,6 @@ ip_nat_fn(unsigned int hooknum,
IP_NF_ASSERT(!((*pskb)->nh.iph->frag_off
& htons(IP_MF|IP_OFFSET)));
- /* If we had a hardware checksum before, it's now invalid */
- if ((*pskb)->ip_summed == CHECKSUM_PARTIAL ||
- (*pskb)->ip_summed == CHECKSUM_COMPLETE)
- if (skb_checksum_help(*pskb))
- return NF_DROP;
-
ct = ip_conntrack_get(*pskb, &ctinfo);
/* Can't track? It's not due to stress, or conntrack would
have dropped it. Hence it's the user's responsibilty to
@@ -146,8 +140,8 @@ ip_nat_fn(unsigned int hooknum,
case IP_CT_RELATED:
case IP_CT_RELATED+IP_CT_IS_REPLY:
if ((*pskb)->nh.iph->protocol == IPPROTO_ICMP) {
- if (!ip_nat_icmp_reply_translation(pskb, ct, maniptype,
- CTINFO2DIR(ctinfo)))
+ if (!ip_nat_icmp_reply_translation(ct, ctinfo,
+ hooknum, pskb))
return NF_DROP;
else
return NF_ACCEPT;
diff --git a/net/ipv4/netfilter/ipt_ECN.c b/net/ipv4/netfilter/ipt_ECN.c
index 4ec43f98fe49..35916c74fe4e 100644
--- a/net/ipv4/netfilter/ipt_ECN.c
+++ b/net/ipv4/netfilter/ipt_ECN.c
@@ -52,7 +52,7 @@ static inline int
set_ect_tcp(struct sk_buff **pskb, const struct ipt_ECN_info *einfo)
{
struct tcphdr _tcph, *tcph;
- u_int16_t diffs[2];
+ u_int16_t oldval;
/* Not enought header? */
tcph = skb_header_pointer(*pskb, (*pskb)->nh.iph->ihl*4,
@@ -70,23 +70,16 @@ set_ect_tcp(struct sk_buff **pskb, const struct ipt_ECN_info *einfo)
return 0;
tcph = (void *)(*pskb)->nh.iph + (*pskb)->nh.iph->ihl*4;
- if (((*pskb)->ip_summed == CHECKSUM_PARTIAL ||
- (*pskb)->ip_summed == CHECKSUM_COMPLETE) &&
- skb_checksum_help(*pskb))
- return 0;
-
- diffs[0] = ((u_int16_t *)tcph)[6];
+ oldval = ((u_int16_t *)tcph)[6];
if (einfo->operation & IPT_ECN_OP_SET_ECE)
tcph->ece = einfo->proto.tcp.ece;
if (einfo->operation & IPT_ECN_OP_SET_CWR)
tcph->cwr = einfo->proto.tcp.cwr;
- diffs[1] = ((u_int16_t *)tcph)[6];
- diffs[0] = diffs[0] ^ 0xFFFF;
- if ((*pskb)->ip_summed != CHECKSUM_UNNECESSARY)
- tcph->check = csum_fold(csum_partial((char *)diffs,
- sizeof(diffs),
- tcph->check^0xFFFF));
+ tcph->check = nf_proto_csum_update((*pskb),
+ oldval ^ 0xFFFF,
+ ((u_int16_t *)tcph)[6],
+ tcph->check, 0);
return 1;
}
diff --git a/net/ipv4/netfilter/ipt_REJECT.c b/net/ipv4/netfilter/ipt_REJECT.c
index 7f905bf2bde5..95c6662b663c 100644
--- a/net/ipv4/netfilter/ipt_REJECT.c
+++ b/net/ipv4/netfilter/ipt_REJECT.c
@@ -185,6 +185,7 @@ static void send_reset(struct sk_buff *oldskb, int hook)
tcph->urg_ptr = 0;
/* Adjust TCP checksum */
+ nskb->ip_summed = CHECKSUM_NONE;
tcph->check = 0;
tcph->check = tcp_v4_check(tcph, sizeof(struct tcphdr),
nskb->nh.iph->saddr,
diff --git a/net/ipv4/netfilter/ipt_TCPMSS.c b/net/ipv4/netfilter/ipt_TCPMSS.c
index c998dc0fcd15..0fce85e05507 100644
--- a/net/ipv4/netfilter/ipt_TCPMSS.c
+++ b/net/ipv4/netfilter/ipt_TCPMSS.c
@@ -27,14 +27,6 @@ MODULE_DESCRIPTION("iptables TCP MSS modification module");
#define DEBUGP(format, args...)
#endif
-static u_int16_t
-cheat_check(u_int32_t oldvalinv, u_int32_t newval, u_int16_t oldcheck)
-{
- u_int32_t diffs[] = { oldvalinv, newval };
- return csum_fold(csum_partial((char *)diffs, sizeof(diffs),
- oldcheck^0xFFFF));
-}
-
static inline unsigned int
optlen(const u_int8_t *opt, unsigned int offset)
{
@@ -62,11 +54,6 @@ ipt_tcpmss_target(struct sk_buff **pskb,
if (!skb_make_writable(pskb, (*pskb)->len))
return NF_DROP;
- if (((*pskb)->ip_summed == CHECKSUM_PARTIAL ||
- (*pskb)->ip_summed == CHECKSUM_COMPLETE) &&
- skb_checksum_help(*pskb))
- return NF_DROP;
-
iph = (*pskb)->nh.iph;
tcplen = (*pskb)->len - iph->ihl*4;
@@ -120,9 +107,10 @@ ipt_tcpmss_target(struct sk_buff **pskb,
opt[i+2] = (newmss & 0xff00) >> 8;
opt[i+3] = (newmss & 0x00ff);
- tcph->check = cheat_check(htons(oldmss)^0xFFFF,
- htons(newmss),
- tcph->check);
+ tcph->check = nf_proto_csum_update(*pskb,
+ htons(oldmss)^0xFFFF,
+ htons(newmss),
+ tcph->check, 0);
DEBUGP(KERN_INFO "ipt_tcpmss_target: %u.%u.%u.%u:%hu"
"->%u.%u.%u.%u:%hu changed TCP MSS option"
@@ -162,8 +150,10 @@ ipt_tcpmss_target(struct sk_buff **pskb,
opt = (u_int8_t *)tcph + sizeof(struct tcphdr);
memmove(opt + TCPOLEN_MSS, opt, tcplen - sizeof(struct tcphdr));
- tcph->check = cheat_check(htons(tcplen) ^ 0xFFFF,
- htons(tcplen + TCPOLEN_MSS), tcph->check);
+ tcph->check = nf_proto_csum_update(*pskb,
+ htons(tcplen) ^ 0xFFFF,
+ htons(tcplen + TCPOLEN_MSS),
+ tcph->check, 1);
tcplen += TCPOLEN_MSS;
opt[0] = TCPOPT_MSS;
@@ -171,16 +161,19 @@ ipt_tcpmss_target(struct sk_buff **pskb,
opt[2] = (newmss & 0xff00) >> 8;
opt[3] = (newmss & 0x00ff);
- tcph->check = cheat_check(~0, *((u_int32_t *)opt), tcph->check);
+ tcph->check = nf_proto_csum_update(*pskb, ~0, *((u_int32_t *)opt),
+ tcph->check, 0);
oldval = ((u_int16_t *)tcph)[6];
tcph->doff += TCPOLEN_MSS/4;
- tcph->check = cheat_check(oldval ^ 0xFFFF,
- ((u_int16_t *)tcph)[6], tcph->check);
+ tcph->check = nf_proto_csum_update(*pskb,
+ oldval ^ 0xFFFF,
+ ((u_int16_t *)tcph)[6],
+ tcph->check, 0);
newtotlen = htons(ntohs(iph->tot_len) + TCPOLEN_MSS);
- iph->check = cheat_check(iph->tot_len ^ 0xFFFF,
- newtotlen, iph->check);
+ iph->check = nf_csum_update(iph->tot_len ^ 0xFFFF,
+ newtotlen, iph->check);
iph->tot_len = newtotlen;
DEBUGP(KERN_INFO "ipt_tcpmss_target: %u.%u.%u.%u:%hu"
diff --git a/net/netfilter/core.c b/net/netfilter/core.c
index 5d29d5e23624..27f639f3ac2a 100644
--- a/net/netfilter/core.c
+++ b/net/netfilter/core.c
@@ -222,6 +222,28 @@ copy_skb:
}
EXPORT_SYMBOL(skb_make_writable);
+u_int16_t nf_csum_update(u_int32_t oldval, u_int32_t newval, u_int32_t csum)
+{
+ u_int32_t diff[] = { oldval, newval };
+
+ return csum_fold(csum_partial((char *)diff, sizeof(diff), ~csum));
+}
+EXPORT_SYMBOL(nf_csum_update);
+
+u_int16_t nf_proto_csum_update(struct sk_buff *skb,
+ u_int32_t oldval, u_int32_t newval,
+ u_int16_t csum, int pseudohdr)
+{
+ if (skb->ip_summed != CHECKSUM_PARTIAL) {
+ csum = nf_csum_update(oldval, newval, csum);
+ if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
+ skb->csum = nf_csum_update(oldval, newval, skb->csum);
+ } else if (pseudohdr)
+ csum = ~nf_csum_update(oldval, newval, ~csum);
+
+ return csum;
+}
+EXPORT_SYMBOL(nf_proto_csum_update);
/* This does not belong here, but locally generated errors need it if connection
tracking in use: without this, connection may not be in hash table, and hence
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