linux 2.6.16.38 w/ vs2.0.3-rc1

[linux-2.6.git] / net / netfilter / nf_conntrack_proto_tcp.c

diff --git a/net/netfilter/nf_conntrack_proto_tcp.c b/net/netfilter/nf_conntrack_proto_tcp.c
index af8adcb..6492ed6 100644 (file)
--- a/net/netfilter/nf_conntrack_proto_tcp.c
+++ b/net/netfilter/nf_conntrack_proto_tcp.c
@@ -24,6 +24,7 @@
  * version 2.2
  */
 
+#include <linux/config.h>
 #include <linux/types.h>
 #include <linux/sched.h>
 #include <linux/timer.h>
@@ -798,7 +799,8 @@ static int tcp_error(struct sk_buff *skb,
                     unsigned int dataoff,
                     enum ip_conntrack_info *ctinfo,
                     int pf,
-                    unsigned int hooknum)
+                    unsigned int hooknum,
+                    int(*csum)(const struct sk_buff *,unsigned int))
 {
        struct tcphdr _tcph, *th;
        unsigned int tcplen = skb->len - dataoff;
@@ -827,10 +829,10 @@ static int tcp_error(struct sk_buff *skb,
         * and moreover root might send raw packets.
         */
        /* FIXME: Source route IP option packets --RR */
-       if (nf_conntrack_checksum &&
-           ((pf == PF_INET && hooknum == NF_IP_PRE_ROUTING) ||
-            (pf == PF_INET6 && hooknum == NF_IP6_PRE_ROUTING)) &&
-           nf_checksum(skb, hooknum, dataoff, IPPROTO_TCP, pf)) {
+       if (((pf == PF_INET && hooknum == NF_IP_PRE_ROUTING) ||
+            (pf == PF_INET6 && hooknum  == NF_IP6_PRE_ROUTING))
+           && skb->ip_summed != CHECKSUM_UNNECESSARY
+           && csum(skb, dataoff)) {
                if (LOG_INVALID(IPPROTO_TCP))
                        nf_log_packet(pf, 0, skb, NULL, NULL, NULL,
                                  "nf_ct_tcp: bad TCP checksum ");
@@ -849,6 +851,44 @@ static int tcp_error(struct sk_buff *skb,
        return NF_ACCEPT;
 }
 
+static int csum4(const struct sk_buff *skb, unsigned int dataoff)
+{
+       return csum_tcpudp_magic(skb->nh.iph->saddr, skb->nh.iph->daddr,
+                                skb->len - dataoff, IPPROTO_TCP,
+                                skb->ip_summed == CHECKSUM_HW ? skb->csum
+                                : skb_checksum(skb, dataoff,
+                                               skb->len - dataoff, 0));
+}
+
+static int csum6(const struct sk_buff *skb, unsigned int dataoff)
+{
+       return csum_ipv6_magic(&skb->nh.ipv6h->saddr, &skb->nh.ipv6h->daddr,
+                              skb->len - dataoff, IPPROTO_TCP,
+                              skb->ip_summed == CHECKSUM_HW
+                              ? csum_sub(skb->csum,
+                                         skb_checksum(skb, 0, dataoff, 0))
+                              : skb_checksum(skb, dataoff, skb->len - dataoff,
+                                             0));
+}
+
+static int tcp_error4(struct sk_buff *skb,
+                     unsigned int dataoff,
+                     enum ip_conntrack_info *ctinfo,
+                     int pf,
+                     unsigned int hooknum)
+{
+       return tcp_error(skb, dataoff, ctinfo, pf, hooknum, csum4);
+}
+
+static int tcp_error6(struct sk_buff *skb,
+                     unsigned int dataoff,
+                     enum ip_conntrack_info *ctinfo,
+                     int pf,
+                     unsigned int hooknum)
+{
+       return tcp_error(skb, dataoff, ctinfo, pf, hooknum, csum6);
+}
+
 /* Returns verdict for packet, or -1 for invalid. */
 static int tcp_packet(struct nf_conn *conntrack,
                      const struct sk_buff *skb,
@@ -1178,7 +1218,7 @@ struct nf_conntrack_protocol nf_conntrack_protocol_tcp4 =
        .print_conntrack        = tcp_print_conntrack,
        .packet                 = tcp_packet,
        .new                    = tcp_new,
-       .error                  = tcp_error,
+       .error                  = tcp_error4,
 #if defined(CONFIG_NF_CT_NETLINK) || \
     defined(CONFIG_NF_CT_NETLINK_MODULE)
        .to_nfattr              = tcp_to_nfattr,
@@ -1199,7 +1239,7 @@ struct nf_conntrack_protocol nf_conntrack_protocol_tcp6 =
        .print_conntrack        = tcp_print_conntrack,
        .packet                 = tcp_packet,
        .new                    = tcp_new,
-       .error                  = tcp_error,
+       .error                  = tcp_error6,
 #if defined(CONFIG_NF_CT_NETLINK) || \
     defined(CONFIG_NF_CT_NETLINK_MODULE)
        .to_nfattr              = tcp_to_nfattr,