// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* ip_vs_proto_tcp.c: TCP load balancing support for IPVS
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*
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* Authors: Wensong Zhang <wensong@linuxvirtualserver.org>
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* Julian Anastasov <ja@ssi.bg>
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*
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* Changes: Hans Schillstrom <hans.schillstrom@ericsson.com>
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*
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* Network name space (netns) aware.
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* Global data moved to netns i.e struct netns_ipvs
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* tcp_timeouts table has copy per netns in a hash table per
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* protocol ip_vs_proto_data and is handled by netns
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*/
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#define KMSG_COMPONENT "IPVS"
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#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
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#include <linux/kernel.h>
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#include <linux/ip.h>
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#include <linux/tcp.h> /* for tcphdr */
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#include <net/ip.h>
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#include <net/tcp.h> /* for csum_tcpudp_magic */
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#include <net/ip6_checksum.h>
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#include <linux/netfilter.h>
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#include <linux/netfilter_ipv4.h>
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#include <linux/indirect_call_wrapper.h>
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#include <net/ip_vs.h>
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static int
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tcp_csum_check(int af, struct sk_buff *skb, struct ip_vs_protocol *pp);
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static int
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tcp_conn_schedule(struct netns_ipvs *ipvs, int af, struct sk_buff *skb,
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struct ip_vs_proto_data *pd,
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int *verdict, struct ip_vs_conn **cpp,
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struct ip_vs_iphdr *iph)
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{
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struct ip_vs_service *svc;
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struct tcphdr _tcph, *th;
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__be16 _ports[2], *ports = NULL;
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/* In the event of icmp, we're only guaranteed to have the first 8
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* bytes of the transport header, so we only check the rest of the
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* TCP packet for non-ICMP packets
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*/
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if (likely(!ip_vs_iph_icmp(iph))) {
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th = skb_header_pointer(skb, iph->len, sizeof(_tcph), &_tcph);
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if (th) {
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if (th->rst || !(sysctl_sloppy_tcp(ipvs) || th->syn))
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return 1;
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ports = &th->source;
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}
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} else {
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ports = skb_header_pointer(
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skb, iph->len, sizeof(_ports), &_ports);
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}
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if (!ports) {
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*verdict = NF_DROP;
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return 0;
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}
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/* No !th->ack check to allow scheduling on SYN+ACK for Active FTP */
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if (likely(!ip_vs_iph_inverse(iph)))
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svc = ip_vs_service_find(ipvs, af, skb->mark, iph->protocol,
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&iph->daddr, ports[1]);
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else
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svc = ip_vs_service_find(ipvs, af, skb->mark, iph->protocol,
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&iph->saddr, ports[0]);
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if (svc) {
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int ignored;
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if (ip_vs_todrop(ipvs)) {
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/*
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* It seems that we are very loaded.
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* We have to drop this packet :(
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*/
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*verdict = NF_DROP;
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return 0;
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}
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/*
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* Let the virtual server select a real server for the
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* incoming connection, and create a connection entry.
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*/
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*cpp = ip_vs_schedule(svc, skb, pd, &ignored, iph);
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if (!*cpp && ignored <= 0) {
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if (!ignored)
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*verdict = ip_vs_leave(svc, skb, pd, iph);
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else
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*verdict = NF_DROP;
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return 0;
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}
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}
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/* NF_ACCEPT */
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return 1;
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}
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static inline void
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tcp_fast_csum_update(int af, struct tcphdr *tcph,
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const union nf_inet_addr *oldip,
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const union nf_inet_addr *newip,
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__be16 oldport, __be16 newport)
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{
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#ifdef CONFIG_IP_VS_IPV6
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if (af == AF_INET6)
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tcph->check =
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csum_fold(ip_vs_check_diff16(oldip->ip6, newip->ip6,
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ip_vs_check_diff2(oldport, newport,
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~csum_unfold(tcph->check))));
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else
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#endif
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tcph->check =
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csum_fold(ip_vs_check_diff4(oldip->ip, newip->ip,
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ip_vs_check_diff2(oldport, newport,
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~csum_unfold(tcph->check))));
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}
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static inline void
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tcp_partial_csum_update(int af, struct tcphdr *tcph,
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const union nf_inet_addr *oldip,
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const union nf_inet_addr *newip,
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__be16 oldlen, __be16 newlen)
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{
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#ifdef CONFIG_IP_VS_IPV6
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if (af == AF_INET6)
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tcph->check =
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~csum_fold(ip_vs_check_diff16(oldip->ip6, newip->ip6,
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ip_vs_check_diff2(oldlen, newlen,
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csum_unfold(tcph->check))));
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else
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#endif
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tcph->check =
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~csum_fold(ip_vs_check_diff4(oldip->ip, newip->ip,
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ip_vs_check_diff2(oldlen, newlen,
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csum_unfold(tcph->check))));
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}
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INDIRECT_CALLABLE_SCOPE int
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tcp_snat_handler(struct sk_buff *skb, struct ip_vs_protocol *pp,
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struct ip_vs_conn *cp, struct ip_vs_iphdr *iph)
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{
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struct tcphdr *tcph;
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unsigned int tcphoff = iph->len;
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bool payload_csum = false;
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int oldlen;
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#ifdef CONFIG_IP_VS_IPV6
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if (cp->af == AF_INET6 && iph->fragoffs)
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return 1;
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#endif
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oldlen = skb->len - tcphoff;
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/* csum_check requires unshared skb */
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if (skb_ensure_writable(skb, tcphoff + sizeof(*tcph)))
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return 0;
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if (unlikely(cp->app != NULL)) {
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int ret;
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/* Some checks before mangling */
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if (!tcp_csum_check(cp->af, skb, pp))
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return 0;
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/* Call application helper if needed */
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if (!(ret = ip_vs_app_pkt_out(cp, skb, iph)))
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return 0;
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/* ret=2: csum update is needed after payload mangling */
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if (ret == 1)
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oldlen = skb->len - tcphoff;
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else
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payload_csum = true;
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}
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tcph = (void *)skb_network_header(skb) + tcphoff;
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tcph->source = cp->vport;
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/* Adjust TCP checksums */
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if (skb->ip_summed == CHECKSUM_PARTIAL) {
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tcp_partial_csum_update(cp->af, tcph, &cp->daddr, &cp->vaddr,
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htons(oldlen),
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htons(skb->len - tcphoff));
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} else if (!payload_csum) {
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/* Only port and addr are changed, do fast csum update */
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tcp_fast_csum_update(cp->af, tcph, &cp->daddr, &cp->vaddr,
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cp->dport, cp->vport);
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if (skb->ip_summed == CHECKSUM_COMPLETE)
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skb->ip_summed = cp->app ?
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CHECKSUM_UNNECESSARY : CHECKSUM_NONE;
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} else {
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/* full checksum calculation */
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tcph->check = 0;
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skb->csum = skb_checksum(skb, tcphoff, skb->len - tcphoff, 0);
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#ifdef CONFIG_IP_VS_IPV6
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if (cp->af == AF_INET6)
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tcph->check = csum_ipv6_magic(&cp->vaddr.in6,
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&cp->caddr.in6,
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skb->len - tcphoff,
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cp->protocol, skb->csum);
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else
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#endif
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tcph->check = csum_tcpudp_magic(cp->vaddr.ip,
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cp->caddr.ip,
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skb->len - tcphoff,
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cp->protocol,
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skb->csum);
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skb->ip_summed = CHECKSUM_UNNECESSARY;
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IP_VS_DBG(11, "O-pkt: %s O-csum=%d (+%zd)\n",
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pp->name, tcph->check,
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(char*)&(tcph->check) - (char*)tcph);
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}
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return 1;
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}
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static int
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tcp_dnat_handler(struct sk_buff *skb, struct ip_vs_protocol *pp,
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struct ip_vs_conn *cp, struct ip_vs_iphdr *iph)
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{
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struct tcphdr *tcph;
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unsigned int tcphoff = iph->len;
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bool payload_csum = false;
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int oldlen;
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#ifdef CONFIG_IP_VS_IPV6
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if (cp->af == AF_INET6 && iph->fragoffs)
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return 1;
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#endif
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oldlen = skb->len - tcphoff;
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/* csum_check requires unshared skb */
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if (skb_ensure_writable(skb, tcphoff + sizeof(*tcph)))
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return 0;
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if (unlikely(cp->app != NULL)) {
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int ret;
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/* Some checks before mangling */
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if (!tcp_csum_check(cp->af, skb, pp))
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return 0;
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/*
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* Attempt ip_vs_app call.
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* It will fix ip_vs_conn and iph ack_seq stuff
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*/
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if (!(ret = ip_vs_app_pkt_in(cp, skb, iph)))
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return 0;
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/* ret=2: csum update is needed after payload mangling */
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if (ret == 1)
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oldlen = skb->len - tcphoff;
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else
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payload_csum = true;
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}
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tcph = (void *)skb_network_header(skb) + tcphoff;
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tcph->dest = cp->dport;
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/*
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* Adjust TCP checksums
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*/
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if (skb->ip_summed == CHECKSUM_PARTIAL) {
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tcp_partial_csum_update(cp->af, tcph, &cp->vaddr, &cp->daddr,
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htons(oldlen),
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htons(skb->len - tcphoff));
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} else if (!payload_csum) {
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/* Only port and addr are changed, do fast csum update */
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tcp_fast_csum_update(cp->af, tcph, &cp->vaddr, &cp->daddr,
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cp->vport, cp->dport);
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if (skb->ip_summed == CHECKSUM_COMPLETE)
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skb->ip_summed = cp->app ?
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CHECKSUM_UNNECESSARY : CHECKSUM_NONE;
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} else {
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/* full checksum calculation */
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tcph->check = 0;
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skb->csum = skb_checksum(skb, tcphoff, skb->len - tcphoff, 0);
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#ifdef CONFIG_IP_VS_IPV6
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if (cp->af == AF_INET6)
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tcph->check = csum_ipv6_magic(&cp->caddr.in6,
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&cp->daddr.in6,
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skb->len - tcphoff,
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cp->protocol, skb->csum);
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else
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#endif
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tcph->check = csum_tcpudp_magic(cp->caddr.ip,
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cp->daddr.ip,
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skb->len - tcphoff,
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cp->protocol,
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skb->csum);
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skb->ip_summed = CHECKSUM_UNNECESSARY;
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}
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return 1;
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}
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static int
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tcp_csum_check(int af, struct sk_buff *skb, struct ip_vs_protocol *pp)
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{
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unsigned int tcphoff;
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#ifdef CONFIG_IP_VS_IPV6
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if (af == AF_INET6)
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tcphoff = sizeof(struct ipv6hdr);
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else
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#endif
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tcphoff = ip_hdrlen(skb);
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switch (skb->ip_summed) {
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case CHECKSUM_NONE:
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skb->csum = skb_checksum(skb, tcphoff, skb->len - tcphoff, 0);
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fallthrough;
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case CHECKSUM_COMPLETE:
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#ifdef CONFIG_IP_VS_IPV6
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if (af == AF_INET6) {
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if (csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
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&ipv6_hdr(skb)->daddr,
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skb->len - tcphoff,
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ipv6_hdr(skb)->nexthdr,
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skb->csum)) {
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IP_VS_DBG_RL_PKT(0, af, pp, skb, 0,
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"Failed checksum for");
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return 0;
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}
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} else
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#endif
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if (csum_tcpudp_magic(ip_hdr(skb)->saddr,
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ip_hdr(skb)->daddr,
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skb->len - tcphoff,
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ip_hdr(skb)->protocol,
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skb->csum)) {
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IP_VS_DBG_RL_PKT(0, af, pp, skb, 0,
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"Failed checksum for");
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return 0;
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}
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break;
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default:
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/* No need to checksum. */
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break;
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}
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return 1;
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}
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#define TCP_DIR_INPUT 0
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#define TCP_DIR_OUTPUT 4
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#define TCP_DIR_INPUT_ONLY 8
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static const int tcp_state_off[IP_VS_DIR_LAST] = {
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[IP_VS_DIR_INPUT] = TCP_DIR_INPUT,
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[IP_VS_DIR_OUTPUT] = TCP_DIR_OUTPUT,
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[IP_VS_DIR_INPUT_ONLY] = TCP_DIR_INPUT_ONLY,
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};
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/*
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* Timeout table[state]
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*/
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static const int tcp_timeouts[IP_VS_TCP_S_LAST+1] = {
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[IP_VS_TCP_S_NONE] = 2*HZ,
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[IP_VS_TCP_S_ESTABLISHED] = 15*60*HZ,
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[IP_VS_TCP_S_SYN_SENT] = 2*60*HZ,
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[IP_VS_TCP_S_SYN_RECV] = 1*60*HZ,
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[IP_VS_TCP_S_FIN_WAIT] = 2*60*HZ,
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[IP_VS_TCP_S_TIME_WAIT] = 2*60*HZ,
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[IP_VS_TCP_S_CLOSE] = 10*HZ,
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[IP_VS_TCP_S_CLOSE_WAIT] = 60*HZ,
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[IP_VS_TCP_S_LAST_ACK] = 30*HZ,
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[IP_VS_TCP_S_LISTEN] = 2*60*HZ,
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[IP_VS_TCP_S_SYNACK] = 120*HZ,
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[IP_VS_TCP_S_LAST] = 2*HZ,
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};
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static const char *const tcp_state_name_table[IP_VS_TCP_S_LAST+1] = {
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[IP_VS_TCP_S_NONE] = "NONE",
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[IP_VS_TCP_S_ESTABLISHED] = "ESTABLISHED",
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[IP_VS_TCP_S_SYN_SENT] = "SYN_SENT",
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[IP_VS_TCP_S_SYN_RECV] = "SYN_RECV",
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[IP_VS_TCP_S_FIN_WAIT] = "FIN_WAIT",
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[IP_VS_TCP_S_TIME_WAIT] = "TIME_WAIT",
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[IP_VS_TCP_S_CLOSE] = "CLOSE",
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[IP_VS_TCP_S_CLOSE_WAIT] = "CLOSE_WAIT",
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[IP_VS_TCP_S_LAST_ACK] = "LAST_ACK",
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[IP_VS_TCP_S_LISTEN] = "LISTEN",
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[IP_VS_TCP_S_SYNACK] = "SYNACK",
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[IP_VS_TCP_S_LAST] = "BUG!",
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};
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static const bool tcp_state_active_table[IP_VS_TCP_S_LAST] = {
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[IP_VS_TCP_S_NONE] = false,
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[IP_VS_TCP_S_ESTABLISHED] = true,
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[IP_VS_TCP_S_SYN_SENT] = true,
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[IP_VS_TCP_S_SYN_RECV] = true,
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[IP_VS_TCP_S_FIN_WAIT] = false,
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[IP_VS_TCP_S_TIME_WAIT] = false,
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[IP_VS_TCP_S_CLOSE] = false,
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[IP_VS_TCP_S_CLOSE_WAIT] = false,
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[IP_VS_TCP_S_LAST_ACK] = false,
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[IP_VS_TCP_S_LISTEN] = false,
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[IP_VS_TCP_S_SYNACK] = true,
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};
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#define sNO IP_VS_TCP_S_NONE
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#define sES IP_VS_TCP_S_ESTABLISHED
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#define sSS IP_VS_TCP_S_SYN_SENT
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#define sSR IP_VS_TCP_S_SYN_RECV
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#define sFW IP_VS_TCP_S_FIN_WAIT
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#define sTW IP_VS_TCP_S_TIME_WAIT
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#define sCL IP_VS_TCP_S_CLOSE
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#define sCW IP_VS_TCP_S_CLOSE_WAIT
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#define sLA IP_VS_TCP_S_LAST_ACK
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#define sLI IP_VS_TCP_S_LISTEN
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#define sSA IP_VS_TCP_S_SYNACK
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struct tcp_states_t {
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int next_state[IP_VS_TCP_S_LAST];
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};
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static const char * tcp_state_name(int state)
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{
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if (state >= IP_VS_TCP_S_LAST)
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return "ERR!";
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return tcp_state_name_table[state] ? tcp_state_name_table[state] : "?";
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}
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static bool tcp_state_active(int state)
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{
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if (state >= IP_VS_TCP_S_LAST)
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return false;
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return tcp_state_active_table[state];
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}
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static struct tcp_states_t tcp_states[] = {
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/* INPUT */
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/* sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
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/*syn*/ {{sSR, sES, sES, sSR, sSR, sSR, sSR, sSR, sSR, sSR, sSR }},
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/*fin*/ {{sCL, sCW, sSS, sTW, sTW, sTW, sCL, sCW, sLA, sLI, sTW }},
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/*ack*/ {{sES, sES, sSS, sES, sFW, sTW, sCL, sCW, sCL, sLI, sES }},
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/*rst*/ {{sCL, sCL, sCL, sSR, sCL, sCL, sCL, sCL, sLA, sLI, sSR }},
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/* OUTPUT */
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/* sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
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/*syn*/ {{sSS, sES, sSS, sSR, sSS, sSS, sSS, sSS, sSS, sLI, sSR }},
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/*fin*/ {{sTW, sFW, sSS, sTW, sFW, sTW, sCL, sTW, sLA, sLI, sTW }},
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/*ack*/ {{sES, sES, sSS, sES, sFW, sTW, sCL, sCW, sLA, sES, sES }},
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/*rst*/ {{sCL, sCL, sSS, sCL, sCL, sTW, sCL, sCL, sCL, sCL, sCL }},
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/* INPUT-ONLY */
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/* sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
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/*syn*/ {{sSR, sES, sES, sSR, sSR, sSR, sSR, sSR, sSR, sSR, sSR }},
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/*fin*/ {{sCL, sFW, sSS, sTW, sFW, sTW, sCL, sCW, sLA, sLI, sTW }},
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/*ack*/ {{sES, sES, sSS, sES, sFW, sTW, sCL, sCW, sCL, sLI, sES }},
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/*rst*/ {{sCL, sCL, sCL, sSR, sCL, sCL, sCL, sCL, sLA, sLI, sCL }},
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};
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static struct tcp_states_t tcp_states_dos[] = {
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/* INPUT */
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/* sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
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/*syn*/ {{sSR, sES, sES, sSR, sSR, sSR, sSR, sSR, sSR, sSR, sSA }},
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/*fin*/ {{sCL, sCW, sSS, sTW, sTW, sTW, sCL, sCW, sLA, sLI, sSA }},
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/*ack*/ {{sES, sES, sSS, sSR, sFW, sTW, sCL, sCW, sCL, sLI, sSA }},
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/*rst*/ {{sCL, sCL, sCL, sSR, sCL, sCL, sCL, sCL, sLA, sLI, sCL }},
|
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/* OUTPUT */
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/* sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
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/*syn*/ {{sSS, sES, sSS, sSA, sSS, sSS, sSS, sSS, sSS, sLI, sSA }},
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/*fin*/ {{sTW, sFW, sSS, sTW, sFW, sTW, sCL, sTW, sLA, sLI, sTW }},
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/*ack*/ {{sES, sES, sSS, sES, sFW, sTW, sCL, sCW, sLA, sES, sES }},
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/*rst*/ {{sCL, sCL, sSS, sCL, sCL, sTW, sCL, sCL, sCL, sCL, sCL }},
|
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/* INPUT-ONLY */
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/* sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
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/*syn*/ {{sSA, sES, sES, sSR, sSA, sSA, sSA, sSA, sSA, sSA, sSA }},
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/*fin*/ {{sCL, sFW, sSS, sTW, sFW, sTW, sCL, sCW, sLA, sLI, sTW }},
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/*ack*/ {{sES, sES, sSS, sES, sFW, sTW, sCL, sCW, sCL, sLI, sES }},
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/*rst*/ {{sCL, sCL, sCL, sSR, sCL, sCL, sCL, sCL, sLA, sLI, sCL }},
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};
|
|
static void tcp_timeout_change(struct ip_vs_proto_data *pd, int flags)
|
{
|
int on = (flags & 1); /* secure_tcp */
|
|
/*
|
** FIXME: change secure_tcp to independent sysctl var
|
** or make it per-service or per-app because it is valid
|
** for most if not for all of the applications. Something
|
** like "capabilities" (flags) for each object.
|
*/
|
pd->tcp_state_table = (on ? tcp_states_dos : tcp_states);
|
}
|
|
static inline int tcp_state_idx(struct tcphdr *th)
|
{
|
if (th->rst)
|
return 3;
|
if (th->syn)
|
return 0;
|
if (th->fin)
|
return 1;
|
if (th->ack)
|
return 2;
|
return -1;
|
}
|
|
static inline void
|
set_tcp_state(struct ip_vs_proto_data *pd, struct ip_vs_conn *cp,
|
int direction, struct tcphdr *th)
|
{
|
int state_idx;
|
int new_state = IP_VS_TCP_S_CLOSE;
|
int state_off = tcp_state_off[direction];
|
|
/*
|
* Update state offset to INPUT_ONLY if necessary
|
* or delete NO_OUTPUT flag if output packet detected
|
*/
|
if (cp->flags & IP_VS_CONN_F_NOOUTPUT) {
|
if (state_off == TCP_DIR_OUTPUT)
|
cp->flags &= ~IP_VS_CONN_F_NOOUTPUT;
|
else
|
state_off = TCP_DIR_INPUT_ONLY;
|
}
|
|
if ((state_idx = tcp_state_idx(th)) < 0) {
|
IP_VS_DBG(8, "tcp_state_idx=%d!!!\n", state_idx);
|
goto tcp_state_out;
|
}
|
|
new_state =
|
pd->tcp_state_table[state_off+state_idx].next_state[cp->state];
|
|
tcp_state_out:
|
if (new_state != cp->state) {
|
struct ip_vs_dest *dest = cp->dest;
|
|
IP_VS_DBG_BUF(8, "%s %s [%c%c%c%c] c:%s:%d v:%s:%d "
|
"d:%s:%d state: %s->%s conn->refcnt:%d\n",
|
pd->pp->name,
|
((state_off == TCP_DIR_OUTPUT) ?
|
"output " : "input "),
|
th->syn ? 'S' : '.',
|
th->fin ? 'F' : '.',
|
th->ack ? 'A' : '.',
|
th->rst ? 'R' : '.',
|
IP_VS_DBG_ADDR(cp->af, &cp->caddr),
|
ntohs(cp->cport),
|
IP_VS_DBG_ADDR(cp->af, &cp->vaddr),
|
ntohs(cp->vport),
|
IP_VS_DBG_ADDR(cp->daf, &cp->daddr),
|
ntohs(cp->dport),
|
tcp_state_name(cp->state),
|
tcp_state_name(new_state),
|
refcount_read(&cp->refcnt));
|
|
if (dest) {
|
if (!(cp->flags & IP_VS_CONN_F_INACTIVE) &&
|
!tcp_state_active(new_state)) {
|
atomic_dec(&dest->activeconns);
|
atomic_inc(&dest->inactconns);
|
cp->flags |= IP_VS_CONN_F_INACTIVE;
|
} else if ((cp->flags & IP_VS_CONN_F_INACTIVE) &&
|
tcp_state_active(new_state)) {
|
atomic_inc(&dest->activeconns);
|
atomic_dec(&dest->inactconns);
|
cp->flags &= ~IP_VS_CONN_F_INACTIVE;
|
}
|
}
|
if (new_state == IP_VS_TCP_S_ESTABLISHED)
|
ip_vs_control_assure_ct(cp);
|
}
|
|
if (likely(pd))
|
cp->timeout = pd->timeout_table[cp->state = new_state];
|
else /* What to do ? */
|
cp->timeout = tcp_timeouts[cp->state = new_state];
|
}
|
|
/*
|
* Handle state transitions
|
*/
|
static void
|
tcp_state_transition(struct ip_vs_conn *cp, int direction,
|
const struct sk_buff *skb,
|
struct ip_vs_proto_data *pd)
|
{
|
struct tcphdr _tcph, *th;
|
|
#ifdef CONFIG_IP_VS_IPV6
|
int ihl = cp->af == AF_INET ? ip_hdrlen(skb) : sizeof(struct ipv6hdr);
|
#else
|
int ihl = ip_hdrlen(skb);
|
#endif
|
|
th = skb_header_pointer(skb, ihl, sizeof(_tcph), &_tcph);
|
if (th == NULL)
|
return;
|
|
spin_lock_bh(&cp->lock);
|
set_tcp_state(pd, cp, direction, th);
|
spin_unlock_bh(&cp->lock);
|
}
|
|
static inline __u16 tcp_app_hashkey(__be16 port)
|
{
|
return (((__force u16)port >> TCP_APP_TAB_BITS) ^ (__force u16)port)
|
& TCP_APP_TAB_MASK;
|
}
|
|
|
static int tcp_register_app(struct netns_ipvs *ipvs, struct ip_vs_app *inc)
|
{
|
struct ip_vs_app *i;
|
__u16 hash;
|
__be16 port = inc->port;
|
int ret = 0;
|
struct ip_vs_proto_data *pd = ip_vs_proto_data_get(ipvs, IPPROTO_TCP);
|
|
hash = tcp_app_hashkey(port);
|
|
list_for_each_entry(i, &ipvs->tcp_apps[hash], p_list) {
|
if (i->port == port) {
|
ret = -EEXIST;
|
goto out;
|
}
|
}
|
list_add_rcu(&inc->p_list, &ipvs->tcp_apps[hash]);
|
atomic_inc(&pd->appcnt);
|
|
out:
|
return ret;
|
}
|
|
|
static void
|
tcp_unregister_app(struct netns_ipvs *ipvs, struct ip_vs_app *inc)
|
{
|
struct ip_vs_proto_data *pd = ip_vs_proto_data_get(ipvs, IPPROTO_TCP);
|
|
atomic_dec(&pd->appcnt);
|
list_del_rcu(&inc->p_list);
|
}
|
|
|
static int
|
tcp_app_conn_bind(struct ip_vs_conn *cp)
|
{
|
struct netns_ipvs *ipvs = cp->ipvs;
|
int hash;
|
struct ip_vs_app *inc;
|
int result = 0;
|
|
/* Default binding: bind app only for NAT */
|
if (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ)
|
return 0;
|
|
/* Lookup application incarnations and bind the right one */
|
hash = tcp_app_hashkey(cp->vport);
|
|
list_for_each_entry_rcu(inc, &ipvs->tcp_apps[hash], p_list) {
|
if (inc->port == cp->vport) {
|
if (unlikely(!ip_vs_app_inc_get(inc)))
|
break;
|
|
IP_VS_DBG_BUF(9, "%s(): Binding conn %s:%u->"
|
"%s:%u to app %s on port %u\n",
|
__func__,
|
IP_VS_DBG_ADDR(cp->af, &cp->caddr),
|
ntohs(cp->cport),
|
IP_VS_DBG_ADDR(cp->af, &cp->vaddr),
|
ntohs(cp->vport),
|
inc->name, ntohs(inc->port));
|
|
cp->app = inc;
|
if (inc->init_conn)
|
result = inc->init_conn(inc, cp);
|
break;
|
}
|
}
|
|
return result;
|
}
|
|
|
/*
|
* Set LISTEN timeout. (ip_vs_conn_put will setup timer)
|
*/
|
void ip_vs_tcp_conn_listen(struct ip_vs_conn *cp)
|
{
|
struct ip_vs_proto_data *pd = ip_vs_proto_data_get(cp->ipvs, IPPROTO_TCP);
|
|
spin_lock_bh(&cp->lock);
|
cp->state = IP_VS_TCP_S_LISTEN;
|
cp->timeout = (pd ? pd->timeout_table[IP_VS_TCP_S_LISTEN]
|
: tcp_timeouts[IP_VS_TCP_S_LISTEN]);
|
spin_unlock_bh(&cp->lock);
|
}
|
|
/* ---------------------------------------------
|
* timeouts is netns related now.
|
* ---------------------------------------------
|
*/
|
static int __ip_vs_tcp_init(struct netns_ipvs *ipvs, struct ip_vs_proto_data *pd)
|
{
|
ip_vs_init_hash_table(ipvs->tcp_apps, TCP_APP_TAB_SIZE);
|
pd->timeout_table = ip_vs_create_timeout_table((int *)tcp_timeouts,
|
sizeof(tcp_timeouts));
|
if (!pd->timeout_table)
|
return -ENOMEM;
|
pd->tcp_state_table = tcp_states;
|
return 0;
|
}
|
|
static void __ip_vs_tcp_exit(struct netns_ipvs *ipvs, struct ip_vs_proto_data *pd)
|
{
|
kfree(pd->timeout_table);
|
}
|
|
|
struct ip_vs_protocol ip_vs_protocol_tcp = {
|
.name = "TCP",
|
.protocol = IPPROTO_TCP,
|
.num_states = IP_VS_TCP_S_LAST,
|
.dont_defrag = 0,
|
.init = NULL,
|
.exit = NULL,
|
.init_netns = __ip_vs_tcp_init,
|
.exit_netns = __ip_vs_tcp_exit,
|
.register_app = tcp_register_app,
|
.unregister_app = tcp_unregister_app,
|
.conn_schedule = tcp_conn_schedule,
|
.conn_in_get = ip_vs_conn_in_get_proto,
|
.conn_out_get = ip_vs_conn_out_get_proto,
|
.snat_handler = tcp_snat_handler,
|
.dnat_handler = tcp_dnat_handler,
|
.state_name = tcp_state_name,
|
.state_transition = tcp_state_transition,
|
.app_conn_bind = tcp_app_conn_bind,
|
.debug_packet = ip_vs_tcpudp_debug_packet,
|
.timeout_change = tcp_timeout_change,
|
};
|
