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- /*
- * ip_vs_proto_tcp.c: TCP load balancing support for IPVS
- *
- * Authors: Wensong Zhang <wensong@linuxvirtualserver.org>
- * Julian Anastasov <ja@ssi.bg>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- *
- * Changes: Hans Schillstrom <hans.schillstrom@ericsson.com>
- *
- * Network name space (netns) aware.
- * Global data moved to netns i.e struct netns_ipvs
- * tcp_timeouts table has copy per netns in a hash table per
- * protocol ip_vs_proto_data and is handled by netns
- */
- #define KMSG_COMPONENT "IPVS"
- #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
- #include <linux/kernel.h>
- #include <linux/ip.h>
- #include <linux/tcp.h> /* for tcphdr */
- #include <net/ip.h>
- #include <net/tcp.h> /* for csum_tcpudp_magic */
- #include <net/ip6_checksum.h>
- #include <linux/netfilter.h>
- #include <linux/netfilter_ipv4.h>
- #include <net/ip_vs.h>
- static int
- tcp_conn_schedule(struct netns_ipvs *ipvs, int af, struct sk_buff *skb,
- struct ip_vs_proto_data *pd,
- int *verdict, struct ip_vs_conn **cpp,
- struct ip_vs_iphdr *iph)
- {
- struct ip_vs_service *svc;
- struct tcphdr _tcph, *th;
- __be16 _ports[2], *ports = NULL;
- /* In the event of icmp, we're only guaranteed to have the first 8
- * bytes of the transport header, so we only check the rest of the
- * TCP packet for non-ICMP packets
- */
- if (likely(!ip_vs_iph_icmp(iph))) {
- th = skb_header_pointer(skb, iph->len, sizeof(_tcph), &_tcph);
- if (th) {
- if (th->rst || !(sysctl_sloppy_tcp(ipvs) || th->syn))
- return 1;
- ports = &th->source;
- }
- } else {
- ports = skb_header_pointer(
- skb, iph->len, sizeof(_ports), &_ports);
- }
- if (!ports) {
- *verdict = NF_DROP;
- return 0;
- }
- /* No !th->ack check to allow scheduling on SYN+ACK for Active FTP */
- rcu_read_lock();
- if (likely(!ip_vs_iph_inverse(iph)))
- svc = ip_vs_service_find(ipvs, af, skb->mark, iph->protocol,
- &iph->daddr, ports[1]);
- else
- svc = ip_vs_service_find(ipvs, af, skb->mark, iph->protocol,
- &iph->saddr, ports[0]);
- if (svc) {
- int ignored;
- if (ip_vs_todrop(ipvs)) {
- /*
- * It seems that we are very loaded.
- * We have to drop this packet :(
- */
- rcu_read_unlock();
- *verdict = NF_DROP;
- return 0;
- }
- /*
- * Let the virtual server select a real server for the
- * incoming connection, and create a connection entry.
- */
- *cpp = ip_vs_schedule(svc, skb, pd, &ignored, iph);
- if (!*cpp && ignored <= 0) {
- if (!ignored)
- *verdict = ip_vs_leave(svc, skb, pd, iph);
- else
- *verdict = NF_DROP;
- rcu_read_unlock();
- return 0;
- }
- }
- rcu_read_unlock();
- /* NF_ACCEPT */
- return 1;
- }
- static inline void
- tcp_fast_csum_update(int af, struct tcphdr *tcph,
- const union nf_inet_addr *oldip,
- const union nf_inet_addr *newip,
- __be16 oldport, __be16 newport)
- {
- #ifdef CONFIG_IP_VS_IPV6
- if (af == AF_INET6)
- tcph->check =
- csum_fold(ip_vs_check_diff16(oldip->ip6, newip->ip6,
- ip_vs_check_diff2(oldport, newport,
- ~csum_unfold(tcph->check))));
- else
- #endif
- tcph->check =
- csum_fold(ip_vs_check_diff4(oldip->ip, newip->ip,
- ip_vs_check_diff2(oldport, newport,
- ~csum_unfold(tcph->check))));
- }
- static inline void
- tcp_partial_csum_update(int af, struct tcphdr *tcph,
- const union nf_inet_addr *oldip,
- const union nf_inet_addr *newip,
- __be16 oldlen, __be16 newlen)
- {
- #ifdef CONFIG_IP_VS_IPV6
- if (af == AF_INET6)
- tcph->check =
- ~csum_fold(ip_vs_check_diff16(oldip->ip6, newip->ip6,
- ip_vs_check_diff2(oldlen, newlen,
- csum_unfold(tcph->check))));
- else
- #endif
- tcph->check =
- ~csum_fold(ip_vs_check_diff4(oldip->ip, newip->ip,
- ip_vs_check_diff2(oldlen, newlen,
- csum_unfold(tcph->check))));
- }
- static int
- tcp_snat_handler(struct sk_buff *skb, struct ip_vs_protocol *pp,
- struct ip_vs_conn *cp, struct ip_vs_iphdr *iph)
- {
- struct tcphdr *tcph;
- unsigned int tcphoff = iph->len;
- int oldlen;
- int payload_csum = 0;
- #ifdef CONFIG_IP_VS_IPV6
- if (cp->af == AF_INET6 && iph->fragoffs)
- return 1;
- #endif
- oldlen = skb->len - tcphoff;
- /* csum_check requires unshared skb */
- if (!skb_make_writable(skb, tcphoff+sizeof(*tcph)))
- return 0;
- if (unlikely(cp->app != NULL)) {
- int ret;
- /* Some checks before mangling */
- if (pp->csum_check && !pp->csum_check(cp->af, skb, pp))
- return 0;
- /* Call application helper if needed */
- if (!(ret = ip_vs_app_pkt_out(cp, skb)))
- return 0;
- /* ret=2: csum update is needed after payload mangling */
- if (ret == 1)
- oldlen = skb->len - tcphoff;
- else
- payload_csum = 1;
- }
- tcph = (void *)skb_network_header(skb) + tcphoff;
- tcph->source = cp->vport;
- /* Adjust TCP checksums */
- if (skb->ip_summed == CHECKSUM_PARTIAL) {
- tcp_partial_csum_update(cp->af, tcph, &cp->daddr, &cp->vaddr,
- htons(oldlen),
- htons(skb->len - tcphoff));
- } else if (!payload_csum) {
- /* Only port and addr are changed, do fast csum update */
- tcp_fast_csum_update(cp->af, tcph, &cp->daddr, &cp->vaddr,
- cp->dport, cp->vport);
- if (skb->ip_summed == CHECKSUM_COMPLETE)
- skb->ip_summed = (cp->app && pp->csum_check) ?
- CHECKSUM_UNNECESSARY : CHECKSUM_NONE;
- } else {
- /* full checksum calculation */
- tcph->check = 0;
- skb->csum = skb_checksum(skb, tcphoff, skb->len - tcphoff, 0);
- #ifdef CONFIG_IP_VS_IPV6
- if (cp->af == AF_INET6)
- tcph->check = csum_ipv6_magic(&cp->vaddr.in6,
- &cp->caddr.in6,
- skb->len - tcphoff,
- cp->protocol, skb->csum);
- else
- #endif
- tcph->check = csum_tcpudp_magic(cp->vaddr.ip,
- cp->caddr.ip,
- skb->len - tcphoff,
- cp->protocol,
- skb->csum);
- skb->ip_summed = CHECKSUM_UNNECESSARY;
- IP_VS_DBG(11, "O-pkt: %s O-csum=%d (+%zd)\n",
- pp->name, tcph->check,
- (char*)&(tcph->check) - (char*)tcph);
- }
- return 1;
- }
- static int
- tcp_dnat_handler(struct sk_buff *skb, struct ip_vs_protocol *pp,
- struct ip_vs_conn *cp, struct ip_vs_iphdr *iph)
- {
- struct tcphdr *tcph;
- unsigned int tcphoff = iph->len;
- int oldlen;
- int payload_csum = 0;
- #ifdef CONFIG_IP_VS_IPV6
- if (cp->af == AF_INET6 && iph->fragoffs)
- return 1;
- #endif
- oldlen = skb->len - tcphoff;
- /* csum_check requires unshared skb */
- if (!skb_make_writable(skb, tcphoff+sizeof(*tcph)))
- return 0;
- if (unlikely(cp->app != NULL)) {
- int ret;
- /* Some checks before mangling */
- if (pp->csum_check && !pp->csum_check(cp->af, skb, pp))
- return 0;
- /*
- * Attempt ip_vs_app call.
- * It will fix ip_vs_conn and iph ack_seq stuff
- */
- if (!(ret = ip_vs_app_pkt_in(cp, skb)))
- return 0;
- /* ret=2: csum update is needed after payload mangling */
- if (ret == 1)
- oldlen = skb->len - tcphoff;
- else
- payload_csum = 1;
- }
- tcph = (void *)skb_network_header(skb) + tcphoff;
- tcph->dest = cp->dport;
- /*
- * Adjust TCP checksums
- */
- if (skb->ip_summed == CHECKSUM_PARTIAL) {
- tcp_partial_csum_update(cp->af, tcph, &cp->vaddr, &cp->daddr,
- htons(oldlen),
- htons(skb->len - tcphoff));
- } else if (!payload_csum) {
- /* Only port and addr are changed, do fast csum update */
- tcp_fast_csum_update(cp->af, tcph, &cp->vaddr, &cp->daddr,
- cp->vport, cp->dport);
- if (skb->ip_summed == CHECKSUM_COMPLETE)
- skb->ip_summed = (cp->app && pp->csum_check) ?
- CHECKSUM_UNNECESSARY : CHECKSUM_NONE;
- } else {
- /* full checksum calculation */
- tcph->check = 0;
- skb->csum = skb_checksum(skb, tcphoff, skb->len - tcphoff, 0);
- #ifdef CONFIG_IP_VS_IPV6
- if (cp->af == AF_INET6)
- tcph->check = csum_ipv6_magic(&cp->caddr.in6,
- &cp->daddr.in6,
- skb->len - tcphoff,
- cp->protocol, skb->csum);
- else
- #endif
- tcph->check = csum_tcpudp_magic(cp->caddr.ip,
- cp->daddr.ip,
- skb->len - tcphoff,
- cp->protocol,
- skb->csum);
- skb->ip_summed = CHECKSUM_UNNECESSARY;
- }
- return 1;
- }
- static int
- tcp_csum_check(int af, struct sk_buff *skb, struct ip_vs_protocol *pp)
- {
- unsigned int tcphoff;
- #ifdef CONFIG_IP_VS_IPV6
- if (af == AF_INET6)
- tcphoff = sizeof(struct ipv6hdr);
- else
- #endif
- tcphoff = ip_hdrlen(skb);
- switch (skb->ip_summed) {
- case CHECKSUM_NONE:
- skb->csum = skb_checksum(skb, tcphoff, skb->len - tcphoff, 0);
- case CHECKSUM_COMPLETE:
- #ifdef CONFIG_IP_VS_IPV6
- if (af == AF_INET6) {
- if (csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
- &ipv6_hdr(skb)->daddr,
- skb->len - tcphoff,
- ipv6_hdr(skb)->nexthdr,
- skb->csum)) {
- IP_VS_DBG_RL_PKT(0, af, pp, skb, 0,
- "Failed checksum for");
- return 0;
- }
- } else
- #endif
- if (csum_tcpudp_magic(ip_hdr(skb)->saddr,
- ip_hdr(skb)->daddr,
- skb->len - tcphoff,
- ip_hdr(skb)->protocol,
- skb->csum)) {
- IP_VS_DBG_RL_PKT(0, af, pp, skb, 0,
- "Failed checksum for");
- return 0;
- }
- break;
- default:
- /* No need to checksum. */
- break;
- }
- return 1;
- }
- #define TCP_DIR_INPUT 0
- #define TCP_DIR_OUTPUT 4
- #define TCP_DIR_INPUT_ONLY 8
- static const int tcp_state_off[IP_VS_DIR_LAST] = {
- [IP_VS_DIR_INPUT] = TCP_DIR_INPUT,
- [IP_VS_DIR_OUTPUT] = TCP_DIR_OUTPUT,
- [IP_VS_DIR_INPUT_ONLY] = TCP_DIR_INPUT_ONLY,
- };
- /*
- * Timeout table[state]
- */
- static const int tcp_timeouts[IP_VS_TCP_S_LAST+1] = {
- [IP_VS_TCP_S_NONE] = 2*HZ,
- [IP_VS_TCP_S_ESTABLISHED] = 15*60*HZ,
- [IP_VS_TCP_S_SYN_SENT] = 2*60*HZ,
- [IP_VS_TCP_S_SYN_RECV] = 1*60*HZ,
- [IP_VS_TCP_S_FIN_WAIT] = 2*60*HZ,
- [IP_VS_TCP_S_TIME_WAIT] = 2*60*HZ,
- [IP_VS_TCP_S_CLOSE] = 10*HZ,
- [IP_VS_TCP_S_CLOSE_WAIT] = 60*HZ,
- [IP_VS_TCP_S_LAST_ACK] = 30*HZ,
- [IP_VS_TCP_S_LISTEN] = 2*60*HZ,
- [IP_VS_TCP_S_SYNACK] = 120*HZ,
- [IP_VS_TCP_S_LAST] = 2*HZ,
- };
- static const char *const tcp_state_name_table[IP_VS_TCP_S_LAST+1] = {
- [IP_VS_TCP_S_NONE] = "NONE",
- [IP_VS_TCP_S_ESTABLISHED] = "ESTABLISHED",
- [IP_VS_TCP_S_SYN_SENT] = "SYN_SENT",
- [IP_VS_TCP_S_SYN_RECV] = "SYN_RECV",
- [IP_VS_TCP_S_FIN_WAIT] = "FIN_WAIT",
- [IP_VS_TCP_S_TIME_WAIT] = "TIME_WAIT",
- [IP_VS_TCP_S_CLOSE] = "CLOSE",
- [IP_VS_TCP_S_CLOSE_WAIT] = "CLOSE_WAIT",
- [IP_VS_TCP_S_LAST_ACK] = "LAST_ACK",
- [IP_VS_TCP_S_LISTEN] = "LISTEN",
- [IP_VS_TCP_S_SYNACK] = "SYNACK",
- [IP_VS_TCP_S_LAST] = "BUG!",
- };
- #define sNO IP_VS_TCP_S_NONE
- #define sES IP_VS_TCP_S_ESTABLISHED
- #define sSS IP_VS_TCP_S_SYN_SENT
- #define sSR IP_VS_TCP_S_SYN_RECV
- #define sFW IP_VS_TCP_S_FIN_WAIT
- #define sTW IP_VS_TCP_S_TIME_WAIT
- #define sCL IP_VS_TCP_S_CLOSE
- #define sCW IP_VS_TCP_S_CLOSE_WAIT
- #define sLA IP_VS_TCP_S_LAST_ACK
- #define sLI IP_VS_TCP_S_LISTEN
- #define sSA IP_VS_TCP_S_SYNACK
- struct tcp_states_t {
- int next_state[IP_VS_TCP_S_LAST];
- };
- static const char * tcp_state_name(int state)
- {
- if (state >= IP_VS_TCP_S_LAST)
- return "ERR!";
- return tcp_state_name_table[state] ? tcp_state_name_table[state] : "?";
- }
- static struct tcp_states_t tcp_states [] = {
- /* INPUT */
- /* 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, sCW, sSS, sTW, sTW, sTW, sCL, sCW, sLA, sLI, sTW }},
- /*ack*/ {{sES, sES, sSS, sES, sFW, sTW, sCL, sCW, sCL, sLI, sES }},
- /*rst*/ {{sCL, sCL, sCL, sSR, sCL, sCL, sCL, sCL, sLA, sLI, sSR }},
- /* OUTPUT */
- /* 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*/ {{sES, 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*/ {{sES, 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*/ {{sES, sES, sSS, sES, sFW, sTW, sCL, sCW, sCL, sLI, sES }},
- /*rst*/ {{sCL, sCL, sCL, sSR, sCL, sCL, sCL, sCL, sLA, sLI, sCL }},
- };
- 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] %s:%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->daf, &cp->daddr),
- ntohs(cp->dport),
- IP_VS_DBG_ADDR(cp->af, &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;
- }
- }
- }
- 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);
- rcu_read_lock();
- 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;
- rcu_read_unlock();
- 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);
- goto out;
- }
- }
- rcu_read_unlock();
- out:
- 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,
- .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,
- };
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