// SPDX-License-Identifier: GPL-2.0-or-later
/*
* ip_vs_proto_tcp.c: TCP load balancing support for IPVS
*
* Authors: Wensong Zhang <[email protected]>
* Julian Anastasov <[email protected]>
*
* Changes: Hans Schillstrom <[email protected]>
*
* 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 <linux/indirect_call_wrapper.h>
#include <net/ip_vs.h>
static int
tcp_csum_check(int af, struct sk_buff *skb, struct ip_vs_protocol *pp);
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 */
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 :(
*/
*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;
return 0;
}
}
/* 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))));
}
INDIRECT_CALLABLE_SCOPE 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;
bool payload_csum = false;
int oldlen;
#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_ensure_writable(skb, tcphoff + sizeof(*tcph)))
return 0;
if (unlikely(cp->app != NULL)) {
int ret;
/* Some checks before mangling */
if (!tcp_csum_check(cp->af, skb, pp))
return 0;
/* Call application helper if needed */
if (!(ret = ip_vs_app_pkt_out(cp, skb, iph)))
return 0;
/* ret=2: csum update is needed after payload mangling */
if (ret == 1)
oldlen = skb->len - tcphoff;
else
payload_csum = true;
}
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 ?
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;
bool payload_csum = false;
int oldlen;
#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_ensure_writable(skb, tcphoff + sizeof(*tcph)))
return 0;
if (unlikely(cp->app != NULL)) {
int ret;
/* Some checks before mangling */
if (!tcp_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, iph)))
return 0;
/* ret=2: csum update is needed after payload mangling */
if (ret == 1)
oldlen = skb->len - tcphoff;
else
payload_csum = true;
}
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 ?
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);
fallthrough;
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!",
};
static const bool tcp_state_active_table[IP_VS_TCP_S_LAST] = {
[IP_VS_TCP_S_NONE] = false,
[IP_VS_TCP_S_ESTABLISHED] = true,
[IP_VS_TCP_S_SYN_SENT] = true,
[IP_VS_TCP_S_SYN_RECV] = true,
[IP_VS_TCP_S_FIN_WAIT] = false,
[IP_VS_TCP_S_TIME_WAIT] = false,
[IP_VS_TCP_S_CLOSE] = false,
[IP_VS_TCP_S_CLOSE_WAIT] = false,
[IP_VS_TCP_S_LAST_ACK] = false,
[IP_VS_TCP_S_LISTEN] = false,
[IP_VS_TCP_S_SYNACK] = true,
};
#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 bool tcp_state_active(int state)
{
if (state >= IP_VS_TCP_S_LAST)
return false;
return tcp_state_active_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] 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,
};
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