[NETFILTER]: Get rid of HW checksum invalidation
Update hardware checksums incrementally to avoid breaking GSO. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
parent
84fa7933a3
commit
4cf411de49
@ -282,6 +282,12 @@ extern void nf_invalidate_cache(int pf);
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Returns true or false. */
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extern int skb_make_writable(struct sk_buff **pskb, unsigned int writable_len);
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extern u_int16_t nf_csum_update(u_int32_t oldval, u_int32_t newval,
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u_int32_t csum);
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extern u_int16_t nf_proto_csum_update(struct sk_buff *skb,
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u_int32_t oldval, u_int32_t newval,
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u_int16_t csum, int pseudohdr);
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struct nf_afinfo {
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unsigned short family;
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unsigned int (*checksum)(struct sk_buff *skb, unsigned int hook,
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@ -72,10 +72,6 @@ extern unsigned int ip_nat_setup_info(struct ip_conntrack *conntrack,
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extern int ip_nat_used_tuple(const struct ip_conntrack_tuple *tuple,
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const struct ip_conntrack *ignored_conntrack);
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/* Calculate relative checksum. */
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extern u_int16_t ip_nat_cheat_check(u_int32_t oldvalinv,
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u_int32_t newval,
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u_int16_t oldcheck);
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#else /* !__KERNEL__: iptables wants this to compile. */
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#define ip_nat_multi_range ip_nat_multi_range_compat
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#endif /*__KERNEL__*/
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@ -11,8 +11,8 @@ extern unsigned int ip_nat_packet(struct ip_conntrack *ct,
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unsigned int hooknum,
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struct sk_buff **pskb);
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extern int ip_nat_icmp_reply_translation(struct sk_buff **pskb,
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struct ip_conntrack *ct,
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enum ip_nat_manip_type manip,
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enum ip_conntrack_dir dir);
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extern int ip_nat_icmp_reply_translation(struct ip_conntrack *ct,
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enum ip_conntrack_info ctinfo,
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unsigned int hooknum,
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struct sk_buff **pskb);
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#endif /* _IP_NAT_CORE_H */
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@ -101,18 +101,6 @@ static void ip_nat_cleanup_conntrack(struct ip_conntrack *conn)
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write_unlock_bh(&ip_nat_lock);
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}
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/* We do checksum mangling, so if they were wrong before they're still
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* wrong. Also works for incomplete packets (eg. ICMP dest
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* unreachables.) */
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u_int16_t
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ip_nat_cheat_check(u_int32_t oldvalinv, u_int32_t newval, u_int16_t oldcheck)
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{
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u_int32_t diffs[] = { oldvalinv, newval };
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return csum_fold(csum_partial((char *)diffs, sizeof(diffs),
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oldcheck^0xFFFF));
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}
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EXPORT_SYMBOL(ip_nat_cheat_check);
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/* Is this tuple already taken? (not by us) */
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int
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ip_nat_used_tuple(const struct ip_conntrack_tuple *tuple,
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@ -378,12 +366,12 @@ manip_pkt(u_int16_t proto,
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iph = (void *)(*pskb)->data + iphdroff;
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if (maniptype == IP_NAT_MANIP_SRC) {
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iph->check = ip_nat_cheat_check(~iph->saddr, target->src.ip,
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iph->check);
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iph->check = nf_csum_update(~iph->saddr, target->src.ip,
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iph->check);
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iph->saddr = target->src.ip;
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} else {
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iph->check = ip_nat_cheat_check(~iph->daddr, target->dst.ip,
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iph->check);
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iph->check = nf_csum_update(~iph->daddr, target->dst.ip,
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iph->check);
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iph->daddr = target->dst.ip;
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}
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return 1;
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@ -423,10 +411,10 @@ unsigned int ip_nat_packet(struct ip_conntrack *ct,
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EXPORT_SYMBOL_GPL(ip_nat_packet);
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/* Dir is direction ICMP is coming from (opposite to packet it contains) */
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int ip_nat_icmp_reply_translation(struct sk_buff **pskb,
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struct ip_conntrack *ct,
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enum ip_nat_manip_type manip,
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enum ip_conntrack_dir dir)
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int ip_nat_icmp_reply_translation(struct ip_conntrack *ct,
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enum ip_conntrack_info ctinfo,
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unsigned int hooknum,
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struct sk_buff **pskb)
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{
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struct {
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struct icmphdr icmp;
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@ -434,7 +422,9 @@ int ip_nat_icmp_reply_translation(struct sk_buff **pskb,
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} *inside;
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struct ip_conntrack_tuple inner, target;
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int hdrlen = (*pskb)->nh.iph->ihl * 4;
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enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
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unsigned long statusbit;
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enum ip_nat_manip_type manip = HOOK2MANIP(hooknum);
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if (!skb_make_writable(pskb, hdrlen + sizeof(*inside)))
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return 0;
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@ -443,12 +433,8 @@ int ip_nat_icmp_reply_translation(struct sk_buff **pskb,
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/* We're actually going to mangle it beyond trivial checksum
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adjustment, so make sure the current checksum is correct. */
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if ((*pskb)->ip_summed != CHECKSUM_UNNECESSARY) {
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hdrlen = (*pskb)->nh.iph->ihl * 4;
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if ((u16)csum_fold(skb_checksum(*pskb, hdrlen,
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(*pskb)->len - hdrlen, 0)))
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return 0;
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}
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if (nf_ip_checksum(*pskb, hooknum, hdrlen, 0))
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return 0;
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/* Must be RELATED */
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IP_NF_ASSERT((*pskb)->nfctinfo == IP_CT_RELATED ||
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@ -487,12 +473,14 @@ int ip_nat_icmp_reply_translation(struct sk_buff **pskb,
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!manip))
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return 0;
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/* Reloading "inside" here since manip_pkt inner. */
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inside = (void *)(*pskb)->data + (*pskb)->nh.iph->ihl*4;
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inside->icmp.checksum = 0;
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inside->icmp.checksum = csum_fold(skb_checksum(*pskb, hdrlen,
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(*pskb)->len - hdrlen,
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0));
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if ((*pskb)->ip_summed != CHECKSUM_PARTIAL) {
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/* Reloading "inside" here since manip_pkt inner. */
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inside = (void *)(*pskb)->data + (*pskb)->nh.iph->ihl*4;
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inside->icmp.checksum = 0;
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inside->icmp.checksum = csum_fold(skb_checksum(*pskb, hdrlen,
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(*pskb)->len - hdrlen,
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0));
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}
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/* Change outer to look the reply to an incoming packet
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* (proto 0 means don't invert per-proto part). */
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@ -165,7 +165,7 @@ ip_nat_mangle_tcp_packet(struct sk_buff **pskb,
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{
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struct iphdr *iph;
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struct tcphdr *tcph;
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int datalen;
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int oldlen, datalen;
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if (!skb_make_writable(pskb, (*pskb)->len))
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return 0;
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@ -180,13 +180,22 @@ ip_nat_mangle_tcp_packet(struct sk_buff **pskb,
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iph = (*pskb)->nh.iph;
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tcph = (void *)iph + iph->ihl*4;
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oldlen = (*pskb)->len - iph->ihl*4;
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mangle_contents(*pskb, iph->ihl*4 + tcph->doff*4,
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match_offset, match_len, rep_buffer, rep_len);
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datalen = (*pskb)->len - iph->ihl*4;
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tcph->check = 0;
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tcph->check = tcp_v4_check(tcph, datalen, iph->saddr, iph->daddr,
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csum_partial((char *)tcph, datalen, 0));
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if ((*pskb)->ip_summed != CHECKSUM_PARTIAL) {
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tcph->check = 0;
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tcph->check = tcp_v4_check(tcph, datalen,
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iph->saddr, iph->daddr,
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csum_partial((char *)tcph,
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datalen, 0));
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} else
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tcph->check = nf_proto_csum_update(*pskb,
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htons(oldlen) ^ 0xFFFF,
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htons(datalen),
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tcph->check, 1);
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if (rep_len != match_len) {
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set_bit(IPS_SEQ_ADJUST_BIT, &ct->status);
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@ -221,6 +230,7 @@ ip_nat_mangle_udp_packet(struct sk_buff **pskb,
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{
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struct iphdr *iph;
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struct udphdr *udph;
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int datalen, oldlen;
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/* UDP helpers might accidentally mangle the wrong packet */
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iph = (*pskb)->nh.iph;
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@ -238,22 +248,32 @@ ip_nat_mangle_udp_packet(struct sk_buff **pskb,
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iph = (*pskb)->nh.iph;
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udph = (void *)iph + iph->ihl*4;
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oldlen = (*pskb)->len - iph->ihl*4;
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mangle_contents(*pskb, iph->ihl*4 + sizeof(*udph),
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match_offset, match_len, rep_buffer, rep_len);
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/* update the length of the UDP packet */
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udph->len = htons((*pskb)->len - iph->ihl*4);
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datalen = (*pskb)->len - iph->ihl*4;
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udph->len = htons(datalen);
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/* fix udp checksum if udp checksum was previously calculated */
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if (udph->check) {
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int datalen = (*pskb)->len - iph->ihl * 4;
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if (!udph->check && (*pskb)->ip_summed != CHECKSUM_PARTIAL)
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return 1;
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if ((*pskb)->ip_summed != CHECKSUM_PARTIAL) {
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udph->check = 0;
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udph->check = csum_tcpudp_magic(iph->saddr, iph->daddr,
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datalen, IPPROTO_UDP,
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csum_partial((char *)udph,
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datalen, 0));
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}
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if (!udph->check)
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udph->check = -1;
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} else
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udph->check = nf_proto_csum_update(*pskb,
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htons(oldlen) ^ 0xFFFF,
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htons(datalen),
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udph->check, 1);
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return 1;
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}
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EXPORT_SYMBOL(ip_nat_mangle_udp_packet);
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@ -293,11 +313,14 @@ sack_adjust(struct sk_buff *skb,
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ntohl(sack->start_seq), new_start_seq,
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ntohl(sack->end_seq), new_end_seq);
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tcph->check =
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ip_nat_cheat_check(~sack->start_seq, new_start_seq,
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ip_nat_cheat_check(~sack->end_seq,
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new_end_seq,
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tcph->check));
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tcph->check = nf_proto_csum_update(skb,
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~sack->start_seq,
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new_start_seq,
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tcph->check, 0);
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tcph->check = nf_proto_csum_update(skb,
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~sack->end_seq,
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new_end_seq,
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tcph->check, 0);
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sack->start_seq = new_start_seq;
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sack->end_seq = new_end_seq;
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sackoff += sizeof(*sack);
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@ -381,10 +404,10 @@ ip_nat_seq_adjust(struct sk_buff **pskb,
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newack = ntohl(tcph->ack_seq) - other_way->offset_before;
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newack = htonl(newack);
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tcph->check = ip_nat_cheat_check(~tcph->seq, newseq,
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ip_nat_cheat_check(~tcph->ack_seq,
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newack,
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tcph->check));
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tcph->check = nf_proto_csum_update(*pskb, ~tcph->seq, newseq,
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tcph->check, 0);
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tcph->check = nf_proto_csum_update(*pskb, ~tcph->ack_seq, newack,
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tcph->check, 0);
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DEBUGP("Adjusting sequence number from %u->%u, ack from %u->%u\n",
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ntohl(tcph->seq), ntohl(newseq), ntohl(tcph->ack_seq),
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@ -130,9 +130,10 @@ gre_manip_pkt(struct sk_buff **pskb,
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if (greh->csum) {
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/* FIXME: Never tested this code... */
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*(gre_csum(greh)) =
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ip_nat_cheat_check(~*(gre_key(greh)),
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nf_proto_csum_update(*pskb,
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~*(gre_key(greh)),
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tuple->dst.u.gre.key,
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*(gre_csum(greh)));
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*(gre_csum(greh)), 0);
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}
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*(gre_key(greh)) = tuple->dst.u.gre.key;
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break;
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@ -66,10 +66,10 @@ icmp_manip_pkt(struct sk_buff **pskb,
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return 0;
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hdr = (struct icmphdr *)((*pskb)->data + hdroff);
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hdr->checksum = ip_nat_cheat_check(hdr->un.echo.id ^ 0xFFFF,
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tuple->src.u.icmp.id,
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hdr->checksum);
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hdr->checksum = nf_proto_csum_update(*pskb,
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hdr->un.echo.id ^ 0xFFFF,
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tuple->src.u.icmp.id,
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hdr->checksum, 0);
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hdr->un.echo.id = tuple->src.u.icmp.id;
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return 1;
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}
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@ -129,10 +129,9 @@ tcp_manip_pkt(struct sk_buff **pskb,
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if (hdrsize < sizeof(*hdr))
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return 1;
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hdr->check = ip_nat_cheat_check(~oldip, newip,
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ip_nat_cheat_check(oldport ^ 0xFFFF,
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newport,
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hdr->check));
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hdr->check = nf_proto_csum_update(*pskb, ~oldip, newip, hdr->check, 1);
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hdr->check = nf_proto_csum_update(*pskb, oldport ^ 0xFFFF, newport,
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hdr->check, 0);
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return 1;
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}
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@ -113,11 +113,16 @@ udp_manip_pkt(struct sk_buff **pskb,
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newport = tuple->dst.u.udp.port;
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portptr = &hdr->dest;
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}
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if (hdr->check) /* 0 is a special case meaning no checksum */
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hdr->check = ip_nat_cheat_check(~oldip, newip,
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ip_nat_cheat_check(*portptr ^ 0xFFFF,
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newport,
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hdr->check));
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if (hdr->check || (*pskb)->ip_summed == CHECKSUM_PARTIAL) {
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hdr->check = nf_proto_csum_update(*pskb, ~oldip, newip,
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hdr->check, 1);
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hdr->check = nf_proto_csum_update(*pskb,
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*portptr ^ 0xFFFF, newport,
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hdr->check, 0);
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if (!hdr->check)
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hdr->check = -1;
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}
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*portptr = newport;
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return 1;
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}
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@ -110,12 +110,6 @@ ip_nat_fn(unsigned int hooknum,
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IP_NF_ASSERT(!((*pskb)->nh.iph->frag_off
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& htons(IP_MF|IP_OFFSET)));
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/* If we had a hardware checksum before, it's now invalid */
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if ((*pskb)->ip_summed == CHECKSUM_PARTIAL ||
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(*pskb)->ip_summed == CHECKSUM_COMPLETE)
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if (skb_checksum_help(*pskb))
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return NF_DROP;
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ct = ip_conntrack_get(*pskb, &ctinfo);
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/* Can't track? It's not due to stress, or conntrack would
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have dropped it. Hence it's the user's responsibilty to
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@ -146,8 +140,8 @@ ip_nat_fn(unsigned int hooknum,
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case IP_CT_RELATED:
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case IP_CT_RELATED+IP_CT_IS_REPLY:
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if ((*pskb)->nh.iph->protocol == IPPROTO_ICMP) {
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if (!ip_nat_icmp_reply_translation(pskb, ct, maniptype,
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CTINFO2DIR(ctinfo)))
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if (!ip_nat_icmp_reply_translation(ct, ctinfo,
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hooknum, pskb))
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return NF_DROP;
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else
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return NF_ACCEPT;
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@ -52,7 +52,7 @@ static inline int
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set_ect_tcp(struct sk_buff **pskb, const struct ipt_ECN_info *einfo)
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{
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struct tcphdr _tcph, *tcph;
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u_int16_t diffs[2];
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u_int16_t oldval;
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/* Not enought header? */
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tcph = skb_header_pointer(*pskb, (*pskb)->nh.iph->ihl*4,
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@ -70,23 +70,16 @@ set_ect_tcp(struct sk_buff **pskb, const struct ipt_ECN_info *einfo)
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return 0;
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tcph = (void *)(*pskb)->nh.iph + (*pskb)->nh.iph->ihl*4;
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if (((*pskb)->ip_summed == CHECKSUM_PARTIAL ||
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(*pskb)->ip_summed == CHECKSUM_COMPLETE) &&
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skb_checksum_help(*pskb))
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return 0;
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diffs[0] = ((u_int16_t *)tcph)[6];
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oldval = ((u_int16_t *)tcph)[6];
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if (einfo->operation & IPT_ECN_OP_SET_ECE)
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tcph->ece = einfo->proto.tcp.ece;
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if (einfo->operation & IPT_ECN_OP_SET_CWR)
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tcph->cwr = einfo->proto.tcp.cwr;
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diffs[1] = ((u_int16_t *)tcph)[6];
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diffs[0] = diffs[0] ^ 0xFFFF;
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if ((*pskb)->ip_summed != CHECKSUM_UNNECESSARY)
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tcph->check = csum_fold(csum_partial((char *)diffs,
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sizeof(diffs),
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tcph->check^0xFFFF));
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tcph->check = nf_proto_csum_update((*pskb),
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oldval ^ 0xFFFF,
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((u_int16_t *)tcph)[6],
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tcph->check, 0);
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return 1;
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}
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@ -185,6 +185,7 @@ static void send_reset(struct sk_buff *oldskb, int hook)
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tcph->urg_ptr = 0;
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/* Adjust TCP checksum */
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nskb->ip_summed = CHECKSUM_NONE;
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tcph->check = 0;
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tcph->check = tcp_v4_check(tcph, sizeof(struct tcphdr),
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nskb->nh.iph->saddr,
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@ -27,14 +27,6 @@ MODULE_DESCRIPTION("iptables TCP MSS modification module");
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#define DEBUGP(format, args...)
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#endif
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static u_int16_t
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cheat_check(u_int32_t oldvalinv, u_int32_t newval, u_int16_t oldcheck)
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{
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u_int32_t diffs[] = { oldvalinv, newval };
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return csum_fold(csum_partial((char *)diffs, sizeof(diffs),
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oldcheck^0xFFFF));
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}
|
||||
|
||||
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"
|
||||
|
@ -222,6 +222,28 @@ int skb_make_writable(struct sk_buff **pskb, unsigned int writable_len)
|
||||
}
|
||||
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
|
||||
|
Loading…
Reference in New Issue
Block a user