641 lines
16 KiB
C
641 lines
16 KiB
C
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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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* Version: $Id: ip_vs_proto_tcp.c,v 1.3 2002/11/30 01:50:35 wensong Exp $
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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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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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* Changes:
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*
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*/
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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 <linux/netfilter_ipv4.h>
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#include <net/ip_vs.h>
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static struct ip_vs_conn *
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tcp_conn_in_get(const struct sk_buff *skb, struct ip_vs_protocol *pp,
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const struct iphdr *iph, unsigned int proto_off, int inverse)
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{
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__u16 _ports[2], *pptr;
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pptr = skb_header_pointer(skb, proto_off, sizeof(_ports), _ports);
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if (pptr == NULL)
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return NULL;
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if (likely(!inverse)) {
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return ip_vs_conn_in_get(iph->protocol,
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iph->saddr, pptr[0],
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iph->daddr, pptr[1]);
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} else {
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return ip_vs_conn_in_get(iph->protocol,
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iph->daddr, pptr[1],
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iph->saddr, pptr[0]);
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}
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}
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static struct ip_vs_conn *
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tcp_conn_out_get(const struct sk_buff *skb, struct ip_vs_protocol *pp,
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const struct iphdr *iph, unsigned int proto_off, int inverse)
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{
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__u16 _ports[2], *pptr;
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pptr = skb_header_pointer(skb, proto_off, sizeof(_ports), _ports);
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if (pptr == NULL)
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return NULL;
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if (likely(!inverse)) {
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return ip_vs_conn_out_get(iph->protocol,
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iph->saddr, pptr[0],
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iph->daddr, pptr[1]);
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} else {
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return ip_vs_conn_out_get(iph->protocol,
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iph->daddr, pptr[1],
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iph->saddr, pptr[0]);
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}
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}
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static int
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tcp_conn_schedule(struct sk_buff *skb,
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struct ip_vs_protocol *pp,
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int *verdict, struct ip_vs_conn **cpp)
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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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th = skb_header_pointer(skb, skb->nh.iph->ihl*4,
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sizeof(_tcph), &_tcph);
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if (th == NULL) {
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*verdict = NF_DROP;
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return 0;
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}
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if (th->syn &&
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(svc = ip_vs_service_get(skb->nfmark, skb->nh.iph->protocol,
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skb->nh.iph->daddr, th->dest))) {
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if (ip_vs_todrop()) {
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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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ip_vs_service_put(svc);
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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);
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if (!*cpp) {
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*verdict = ip_vs_leave(svc, skb, pp);
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return 0;
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}
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ip_vs_service_put(svc);
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}
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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(struct tcphdr *tcph, u32 oldip, u32 newip,
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u16 oldport, u16 newport)
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{
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tcph->check =
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ip_vs_check_diff(~oldip, newip,
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ip_vs_check_diff(oldport ^ 0xFFFF,
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newport, tcph->check));
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}
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static int
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tcp_snat_handler(struct sk_buff **pskb,
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struct ip_vs_protocol *pp, struct ip_vs_conn *cp)
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{
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struct tcphdr *tcph;
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unsigned int tcphoff = (*pskb)->nh.iph->ihl * 4;
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/* csum_check requires unshared skb */
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if (!ip_vs_make_skb_writable(pskb, tcphoff+sizeof(*tcph)))
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return 0;
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if (unlikely(cp->app != NULL)) {
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/* Some checks before mangling */
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if (pp->csum_check && !pp->csum_check(*pskb, pp))
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return 0;
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/* Call application helper if needed */
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if (!ip_vs_app_pkt_out(cp, pskb))
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return 0;
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}
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tcph = (void *)(*pskb)->nh.iph + tcphoff;
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tcph->source = cp->vport;
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/* Adjust TCP checksums */
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if (!cp->app) {
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/* Only port and addr are changed, do fast csum update */
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tcp_fast_csum_update(tcph, cp->daddr, cp->vaddr,
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cp->dport, cp->vport);
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if ((*pskb)->ip_summed == CHECKSUM_HW)
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(*pskb)->ip_summed = 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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(*pskb)->csum = skb_checksum(*pskb, tcphoff,
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(*pskb)->len - tcphoff, 0);
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tcph->check = csum_tcpudp_magic(cp->vaddr, cp->caddr,
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(*pskb)->len - tcphoff,
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cp->protocol,
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(*pskb)->csum);
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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 **pskb,
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struct ip_vs_protocol *pp, struct ip_vs_conn *cp)
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{
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struct tcphdr *tcph;
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unsigned int tcphoff = (*pskb)->nh.iph->ihl * 4;
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/* csum_check requires unshared skb */
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if (!ip_vs_make_skb_writable(pskb, tcphoff+sizeof(*tcph)))
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return 0;
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if (unlikely(cp->app != NULL)) {
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/* Some checks before mangling */
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if (pp->csum_check && !pp->csum_check(*pskb, 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 (!ip_vs_app_pkt_in(cp, pskb))
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return 0;
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}
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tcph = (void *)(*pskb)->nh.iph + 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 (!cp->app) {
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/* Only port and addr are changed, do fast csum update */
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tcp_fast_csum_update(tcph, cp->vaddr, cp->daddr,
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cp->vport, cp->dport);
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if ((*pskb)->ip_summed == CHECKSUM_HW)
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(*pskb)->ip_summed = 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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(*pskb)->csum = skb_checksum(*pskb, tcphoff,
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(*pskb)->len - tcphoff, 0);
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tcph->check = csum_tcpudp_magic(cp->caddr, cp->daddr,
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(*pskb)->len - tcphoff,
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cp->protocol,
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(*pskb)->csum);
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(*pskb)->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(struct sk_buff *skb, struct ip_vs_protocol *pp)
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{
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unsigned int tcphoff = skb->nh.iph->ihl*4;
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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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case CHECKSUM_HW:
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if (csum_tcpudp_magic(skb->nh.iph->saddr, skb->nh.iph->daddr,
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skb->len - tcphoff,
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skb->nh.iph->protocol, skb->csum)) {
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IP_VS_DBG_RL_PKT(0, 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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/* CHECKSUM_UNNECESSARY */
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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 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 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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#if 0
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/* FIXME: This is going to die */
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static int tcp_timeouts_dos[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] = 8*60*HZ,
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[IP_VS_TCP_S_SYN_SENT] = 60*HZ,
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[IP_VS_TCP_S_SYN_RECV] = 10*HZ,
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[IP_VS_TCP_S_FIN_WAIT] = 60*HZ,
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[IP_VS_TCP_S_TIME_WAIT] = 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] = 100*HZ,
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[IP_VS_TCP_S_LAST] = 2*HZ,
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};
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#endif
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static char * 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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#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 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*/ {{sCL, 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 */
|
||
|
|
/*syn*/ {{sSS, sES, sSS, sSR, sSS, sSS, sSS, sSS, sSS, sLI, sSR }},
|
||
|
|
/*fin*/ {{sTW, sFW, sSS, sTW, sFW, sTW, sCL, sTW, sLA, sLI, sTW }},
|
||
|
|
/*ack*/ {{sES, sES, sSS, sES, sFW, sTW, sCL, sCW, sLA, sES, sES }},
|
||
|
|
/*rst*/ {{sCL, sCL, sSS, sCL, sCL, sTW, sCL, sCL, sCL, sCL, sCL }},
|
||
|
|
|
||
|
|
/* INPUT-ONLY */
|
||
|
|
/* sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
|
||
|
|
/*syn*/ {{sSR, sES, sES, sSR, sSR, sSR, sSR, sSR, sSR, sSR, sSR }},
|
||
|
|
/*fin*/ {{sCL, sFW, sSS, sTW, sFW, sTW, sCL, sCW, sLA, sLI, sTW }},
|
||
|
|
/*ack*/ {{sCL, sES, sSS, sES, sFW, sTW, sCL, sCW, sCL, sLI, sES }},
|
||
|
|
/*rst*/ {{sCL, sCL, sCL, sSR, sCL, sCL, sCL, sCL, sLA, sLI, sCL }},
|
||
|
|
};
|
||
|
|
|
||
|
|
static struct tcp_states_t tcp_states_dos [] = {
|
||
|
|
/* INPUT */
|
||
|
|
/* sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
|
||
|
|
/*syn*/ {{sSR, sES, sES, sSR, sSR, sSR, sSR, sSR, sSR, sSR, sSA }},
|
||
|
|
/*fin*/ {{sCL, sCW, sSS, sTW, sTW, sTW, sCL, sCW, sLA, sLI, sSA }},
|
||
|
|
/*ack*/ {{sCL, sES, sSS, sSR, sFW, sTW, sCL, sCW, sCL, sLI, sSA }},
|
||
|
|
/*rst*/ {{sCL, sCL, sCL, sSR, sCL, sCL, sCL, sCL, sLA, sLI, sCL }},
|
||
|
|
|
||
|
|
/* OUTPUT */
|
||
|
|
/* sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
|
||
|
|
/*syn*/ {{sSS, sES, sSS, sSA, sSS, sSS, sSS, sSS, sSS, sLI, sSA }},
|
||
|
|
/*fin*/ {{sTW, sFW, sSS, sTW, sFW, sTW, sCL, sTW, sLA, sLI, sTW }},
|
||
|
|
/*ack*/ {{sES, sES, sSS, sES, sFW, sTW, sCL, sCW, sLA, sES, sES }},
|
||
|
|
/*rst*/ {{sCL, sCL, sSS, sCL, sCL, sTW, sCL, sCL, sCL, sCL, sCL }},
|
||
|
|
|
||
|
|
/* INPUT-ONLY */
|
||
|
|
/* sNO, sES, sSS, sSR, sFW, sTW, sCL, sCW, sLA, sLI, sSA */
|
||
|
|
/*syn*/ {{sSA, sES, sES, sSR, sSA, sSA, sSA, sSA, sSA, sSA, sSA }},
|
||
|
|
/*fin*/ {{sCL, sFW, sSS, sTW, sFW, sTW, sCL, sCW, sLA, sLI, sTW }},
|
||
|
|
/*ack*/ {{sCL, sES, sSS, sES, sFW, sTW, sCL, sCW, sCL, sLI, sES }},
|
||
|
|
/*rst*/ {{sCL, sCL, sCL, sSR, sCL, sCL, sCL, sCL, sLA, sLI, sCL }},
|
||
|
|
};
|
||
|
|
|
||
|
|
static struct tcp_states_t *tcp_state_table = tcp_states;
|
||
|
|
|
||
|
|
|
||
|
|
static void tcp_timeout_change(struct ip_vs_protocol *pp, 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.
|
||
|
|
*/
|
||
|
|
tcp_state_table = (on? tcp_states_dos : tcp_states);
|
||
|
|
}
|
||
|
|
|
||
|
|
static int
|
||
|
|
tcp_set_state_timeout(struct ip_vs_protocol *pp, char *sname, int to)
|
||
|
|
{
|
||
|
|
return ip_vs_set_state_timeout(pp->timeout_table, IP_VS_TCP_S_LAST,
|
||
|
|
tcp_state_name_table, sname, to);
|
||
|
|
}
|
||
|
|
|
||
|
|
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_protocol *pp, 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 = 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(8, "%s %s [%c%c%c%c] %u.%u.%u.%u:%d->"
|
||
|
|
"%u.%u.%u.%u:%d state: %s->%s cnt:%d\n",
|
||
|
|
pp->name,
|
||
|
|
(state_off==TCP_DIR_OUTPUT)?"output ":"input ",
|
||
|
|
th->syn? 'S' : '.',
|
||
|
|
th->fin? 'F' : '.',
|
||
|
|
th->ack? 'A' : '.',
|
||
|
|
th->rst? 'R' : '.',
|
||
|
|
NIPQUAD(cp->daddr), ntohs(cp->dport),
|
||
|
|
NIPQUAD(cp->caddr), ntohs(cp->cport),
|
||
|
|
tcp_state_name(cp->state),
|
||
|
|
tcp_state_name(new_state),
|
||
|
|
atomic_read(&cp->refcnt));
|
||
|
|
if (dest) {
|
||
|
|
if (!(cp->flags & IP_VS_CONN_F_INACTIVE) &&
|
||
|
|
(new_state != IP_VS_TCP_S_ESTABLISHED)) {
|
||
|
|
atomic_dec(&dest->activeconns);
|
||
|
|
atomic_inc(&dest->inactconns);
|
||
|
|
cp->flags |= IP_VS_CONN_F_INACTIVE;
|
||
|
|
} else if ((cp->flags & IP_VS_CONN_F_INACTIVE) &&
|
||
|
|
(new_state == IP_VS_TCP_S_ESTABLISHED)) {
|
||
|
|
atomic_inc(&dest->activeconns);
|
||
|
|
atomic_dec(&dest->inactconns);
|
||
|
|
cp->flags &= ~IP_VS_CONN_F_INACTIVE;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
cp->timeout = pp->timeout_table[cp->state = new_state];
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Handle state transitions
|
||
|
|
*/
|
||
|
|
static int
|
||
|
|
tcp_state_transition(struct ip_vs_conn *cp, int direction,
|
||
|
|
const struct sk_buff *skb,
|
||
|
|
struct ip_vs_protocol *pp)
|
||
|
|
{
|
||
|
|
struct tcphdr _tcph, *th;
|
||
|
|
|
||
|
|
th = skb_header_pointer(skb, skb->nh.iph->ihl*4,
|
||
|
|
sizeof(_tcph), &_tcph);
|
||
|
|
if (th == NULL)
|
||
|
|
return 0;
|
||
|
|
|
||
|
|
spin_lock(&cp->lock);
|
||
|
|
set_tcp_state(pp, cp, direction, th);
|
||
|
|
spin_unlock(&cp->lock);
|
||
|
|
|
||
|
|
return 1;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Hash table for TCP application incarnations
|
||
|
|
*/
|
||
|
|
#define TCP_APP_TAB_BITS 4
|
||
|
|
#define TCP_APP_TAB_SIZE (1 << TCP_APP_TAB_BITS)
|
||
|
|
#define TCP_APP_TAB_MASK (TCP_APP_TAB_SIZE - 1)
|
||
|
|
|
||
|
|
static struct list_head tcp_apps[TCP_APP_TAB_SIZE];
|
||
|
|
static DEFINE_SPINLOCK(tcp_app_lock);
|
||
|
|
|
||
|
|
static inline __u16 tcp_app_hashkey(__u16 port)
|
||
|
|
{
|
||
|
|
return ((port >> TCP_APP_TAB_BITS) ^ port) & TCP_APP_TAB_MASK;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
static int tcp_register_app(struct ip_vs_app *inc)
|
||
|
|
{
|
||
|
|
struct ip_vs_app *i;
|
||
|
|
__u16 hash, port = inc->port;
|
||
|
|
int ret = 0;
|
||
|
|
|
||
|
|
hash = tcp_app_hashkey(port);
|
||
|
|
|
||
|
|
spin_lock_bh(&tcp_app_lock);
|
||
|
|
list_for_each_entry(i, &tcp_apps[hash], p_list) {
|
||
|
|
if (i->port == port) {
|
||
|
|
ret = -EEXIST;
|
||
|
|
goto out;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
list_add(&inc->p_list, &tcp_apps[hash]);
|
||
|
|
atomic_inc(&ip_vs_protocol_tcp.appcnt);
|
||
|
|
|
||
|
|
out:
|
||
|
|
spin_unlock_bh(&tcp_app_lock);
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
static void
|
||
|
|
tcp_unregister_app(struct ip_vs_app *inc)
|
||
|
|
{
|
||
|
|
spin_lock_bh(&tcp_app_lock);
|
||
|
|
atomic_dec(&ip_vs_protocol_tcp.appcnt);
|
||
|
|
list_del(&inc->p_list);
|
||
|
|
spin_unlock_bh(&tcp_app_lock);
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
static int
|
||
|
|
tcp_app_conn_bind(struct ip_vs_conn *cp)
|
||
|
|
{
|
||
|
|
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);
|
||
|
|
|
||
|
|
spin_lock(&tcp_app_lock);
|
||
|
|
list_for_each_entry(inc, &tcp_apps[hash], p_list) {
|
||
|
|
if (inc->port == cp->vport) {
|
||
|
|
if (unlikely(!ip_vs_app_inc_get(inc)))
|
||
|
|
break;
|
||
|
|
spin_unlock(&tcp_app_lock);
|
||
|
|
|
||
|
|
IP_VS_DBG(9, "%s: Binding conn %u.%u.%u.%u:%u->"
|
||
|
|
"%u.%u.%u.%u:%u to app %s on port %u\n",
|
||
|
|
__FUNCTION__,
|
||
|
|
NIPQUAD(cp->caddr), ntohs(cp->cport),
|
||
|
|
NIPQUAD(cp->vaddr), ntohs(cp->vport),
|
||
|
|
inc->name, ntohs(inc->port));
|
||
|
|
cp->app = inc;
|
||
|
|
if (inc->init_conn)
|
||
|
|
result = inc->init_conn(inc, cp);
|
||
|
|
goto out;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
spin_unlock(&tcp_app_lock);
|
||
|
|
|
||
|
|
out:
|
||
|
|
return result;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Set LISTEN timeout. (ip_vs_conn_put will setup timer)
|
||
|
|
*/
|
||
|
|
void ip_vs_tcp_conn_listen(struct ip_vs_conn *cp)
|
||
|
|
{
|
||
|
|
spin_lock(&cp->lock);
|
||
|
|
cp->state = IP_VS_TCP_S_LISTEN;
|
||
|
|
cp->timeout = ip_vs_protocol_tcp.timeout_table[IP_VS_TCP_S_LISTEN];
|
||
|
|
spin_unlock(&cp->lock);
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
static void tcp_init(struct ip_vs_protocol *pp)
|
||
|
|
{
|
||
|
|
IP_VS_INIT_HASH_TABLE(tcp_apps);
|
||
|
|
pp->timeout_table = tcp_timeouts;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
static void tcp_exit(struct ip_vs_protocol *pp)
|
||
|
|
{
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
struct ip_vs_protocol ip_vs_protocol_tcp = {
|
||
|
|
.name = "TCP",
|
||
|
|
.protocol = IPPROTO_TCP,
|
||
|
|
.dont_defrag = 0,
|
||
|
|
.appcnt = ATOMIC_INIT(0),
|
||
|
|
.init = tcp_init,
|
||
|
|
.exit = tcp_exit,
|
||
|
|
.register_app = tcp_register_app,
|
||
|
|
.unregister_app = tcp_unregister_app,
|
||
|
|
.conn_schedule = tcp_conn_schedule,
|
||
|
|
.conn_in_get = tcp_conn_in_get,
|
||
|
|
.conn_out_get = tcp_conn_out_get,
|
||
|
|
.snat_handler = tcp_snat_handler,
|
||
|
|
.dnat_handler = tcp_dnat_handler,
|
||
|
|
.csum_check = tcp_csum_check,
|
||
|
|
.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,
|
||
|
|
.set_state_timeout = tcp_set_state_timeout,
|
||
|
|
};
|