2 * IPVS An implementation of the IP virtual server support for the
3 * LINUX operating system. IPVS is now implemented as a module
4 * over the Netfilter framework. IPVS can be used to build a
5 * high-performance and highly available server based on a
8 * Authors: Wensong Zhang <wensong@linuxvirtualserver.org>
9 * Peter Kese <peter.kese@ijs.si>
10 * Julian Anastasov <ja@ssi.bg>
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version
15 * 2 of the License, or (at your option) any later version.
17 * The IPVS code for kernel 2.2 was done by Wensong Zhang and Peter Kese,
18 * with changes/fixes from Julian Anastasov, Lars Marowsky-Bree, Horms
22 * Paul `Rusty' Russell properly handle non-linear skbs
23 * Harald Welte don't use nfcache
27 #define KMSG_COMPONENT "IPVS"
28 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
30 #include <linux/module.h>
31 #include <linux/kernel.h>
33 #include <linux/tcp.h>
34 #include <linux/sctp.h>
35 #include <linux/icmp.h>
36 #include <linux/slab.h>
41 #include <net/icmp.h> /* for icmp_send */
42 #include <net/route.h>
43 #include <net/ip6_checksum.h>
44 #include <net/netns/generic.h> /* net_generic() */
46 #include <linux/netfilter.h>
47 #include <linux/netfilter_ipv4.h>
49 #ifdef CONFIG_IP_VS_IPV6
51 #include <linux/netfilter_ipv6.h>
52 #include <net/ip6_route.h>
55 #include <net/ip_vs.h>
58 EXPORT_SYMBOL(register_ip_vs_scheduler);
59 EXPORT_SYMBOL(unregister_ip_vs_scheduler);
60 EXPORT_SYMBOL(ip_vs_proto_name);
61 EXPORT_SYMBOL(ip_vs_conn_new);
62 EXPORT_SYMBOL(ip_vs_conn_in_get);
63 EXPORT_SYMBOL(ip_vs_conn_out_get);
64 #ifdef CONFIG_IP_VS_PROTO_TCP
65 EXPORT_SYMBOL(ip_vs_tcp_conn_listen);
67 EXPORT_SYMBOL(ip_vs_conn_put);
68 #ifdef CONFIG_IP_VS_DEBUG
69 EXPORT_SYMBOL(ip_vs_get_debug_level);
72 int ip_vs_net_id __read_mostly;
73 #ifdef IP_VS_GENERIC_NETNS
74 EXPORT_SYMBOL(ip_vs_net_id);
76 /* netns cnt used for uniqueness */
77 static atomic_t ipvs_netns_cnt = ATOMIC_INIT(0);
79 /* ID used in ICMP lookups */
80 #define icmp_id(icmph) (((icmph)->un).echo.id)
81 #define icmpv6_id(icmph) (icmph->icmp6_dataun.u_echo.identifier)
83 const char *ip_vs_proto_name(unsigned proto)
98 #ifdef CONFIG_IP_VS_IPV6
103 sprintf(buf, "IP_%d", proto);
108 void ip_vs_init_hash_table(struct list_head *table, int rows)
111 INIT_LIST_HEAD(&table[rows]);
115 ip_vs_in_stats(struct ip_vs_conn *cp, struct sk_buff *skb)
117 struct ip_vs_dest *dest = cp->dest;
118 struct netns_ipvs *ipvs = net_ipvs(skb_net(skb));
120 if (dest && (dest->flags & IP_VS_DEST_F_AVAILABLE)) {
121 struct ip_vs_cpu_stats *s;
123 s = this_cpu_ptr(dest->stats.cpustats);
125 u64_stats_update_begin(&s->syncp);
126 s->ustats.inbytes += skb->len;
127 u64_stats_update_end(&s->syncp);
129 s = this_cpu_ptr(dest->svc->stats.cpustats);
131 u64_stats_update_begin(&s->syncp);
132 s->ustats.inbytes += skb->len;
133 u64_stats_update_end(&s->syncp);
135 s = this_cpu_ptr(ipvs->tot_stats.cpustats);
137 u64_stats_update_begin(&s->syncp);
138 s->ustats.inbytes += skb->len;
139 u64_stats_update_end(&s->syncp);
145 ip_vs_out_stats(struct ip_vs_conn *cp, struct sk_buff *skb)
147 struct ip_vs_dest *dest = cp->dest;
148 struct netns_ipvs *ipvs = net_ipvs(skb_net(skb));
150 if (dest && (dest->flags & IP_VS_DEST_F_AVAILABLE)) {
151 struct ip_vs_cpu_stats *s;
153 s = this_cpu_ptr(dest->stats.cpustats);
155 u64_stats_update_begin(&s->syncp);
156 s->ustats.outbytes += skb->len;
157 u64_stats_update_end(&s->syncp);
159 s = this_cpu_ptr(dest->svc->stats.cpustats);
161 u64_stats_update_begin(&s->syncp);
162 s->ustats.outbytes += skb->len;
163 u64_stats_update_end(&s->syncp);
165 s = this_cpu_ptr(ipvs->tot_stats.cpustats);
167 u64_stats_update_begin(&s->syncp);
168 s->ustats.outbytes += skb->len;
169 u64_stats_update_end(&s->syncp);
175 ip_vs_conn_stats(struct ip_vs_conn *cp, struct ip_vs_service *svc)
177 struct netns_ipvs *ipvs = net_ipvs(svc->net);
178 struct ip_vs_cpu_stats *s;
180 s = this_cpu_ptr(cp->dest->stats.cpustats);
183 s = this_cpu_ptr(svc->stats.cpustats);
186 s = this_cpu_ptr(ipvs->tot_stats.cpustats);
192 ip_vs_set_state(struct ip_vs_conn *cp, int direction,
193 const struct sk_buff *skb,
194 struct ip_vs_proto_data *pd)
196 if (unlikely(!pd->pp->state_transition))
198 return pd->pp->state_transition(cp, direction, skb, pd);
202 ip_vs_conn_fill_param_persist(const struct ip_vs_service *svc,
203 struct sk_buff *skb, int protocol,
204 const union nf_inet_addr *caddr, __be16 cport,
205 const union nf_inet_addr *vaddr, __be16 vport,
206 struct ip_vs_conn_param *p)
208 ip_vs_conn_fill_param(svc->net, svc->af, protocol, caddr, cport, vaddr,
211 if (p->pe && p->pe->fill_param)
212 return p->pe->fill_param(p, skb);
218 * IPVS persistent scheduling function
219 * It creates a connection entry according to its template if exists,
220 * or selects a server and creates a connection entry plus a template.
221 * Locking: we are svc user (svc->refcnt), so we hold all dests too
222 * Protocols supported: TCP, UDP
224 static struct ip_vs_conn *
225 ip_vs_sched_persist(struct ip_vs_service *svc,
227 __be16 src_port, __be16 dst_port, int *ignored)
229 struct ip_vs_conn *cp = NULL;
230 struct ip_vs_iphdr iph;
231 struct ip_vs_dest *dest;
232 struct ip_vs_conn *ct;
233 __be16 dport = 0; /* destination port to forward */
235 struct ip_vs_conn_param param;
236 union nf_inet_addr snet; /* source network of the client,
239 ip_vs_fill_iphdr(svc->af, skb_network_header(skb), &iph);
241 /* Mask saddr with the netmask to adjust template granularity */
242 #ifdef CONFIG_IP_VS_IPV6
243 if (svc->af == AF_INET6)
244 ipv6_addr_prefix(&snet.in6, &iph.saddr.in6, svc->netmask);
247 snet.ip = iph.saddr.ip & svc->netmask;
249 IP_VS_DBG_BUF(6, "p-schedule: src %s:%u dest %s:%u "
251 IP_VS_DBG_ADDR(svc->af, &iph.saddr), ntohs(src_port),
252 IP_VS_DBG_ADDR(svc->af, &iph.daddr), ntohs(dst_port),
253 IP_VS_DBG_ADDR(svc->af, &snet));
256 * As far as we know, FTP is a very complicated network protocol, and
257 * it uses control connection and data connections. For active FTP,
258 * FTP server initialize data connection to the client, its source port
259 * is often 20. For passive FTP, FTP server tells the clients the port
260 * that it passively listens to, and the client issues the data
261 * connection. In the tunneling or direct routing mode, the load
262 * balancer is on the client-to-server half of connection, the port
263 * number is unknown to the load balancer. So, a conn template like
264 * <caddr, 0, vaddr, 0, daddr, 0> is created for persistent FTP
265 * service, and a template like <caddr, 0, vaddr, vport, daddr, dport>
266 * is created for other persistent services.
269 int protocol = iph.protocol;
270 const union nf_inet_addr *vaddr = &iph.daddr;
271 const union nf_inet_addr fwmark = { .ip = htonl(svc->fwmark) };
274 if (dst_port == svc->port) {
276 * <protocol, caddr, 0, vaddr, vport, daddr, dport>
278 * <protocol, caddr, 0, vaddr, 0, daddr, 0>
280 if (svc->port != FTPPORT)
283 /* Note: persistent fwmark-based services and
284 * persistent port zero service are handled here.
286 * <IPPROTO_IP,caddr,0,fwmark,0,daddr,0>
287 * port zero template:
288 * <protocol,caddr,0,vaddr,0,daddr,0>
291 protocol = IPPROTO_IP;
295 /* return *ignored = -1 so NF_DROP can be used */
296 if (ip_vs_conn_fill_param_persist(svc, skb, protocol, &snet, 0,
297 vaddr, vport, ¶m) < 0) {
303 /* Check if a template already exists */
304 ct = ip_vs_ct_in_get(¶m);
305 if (!ct || !ip_vs_check_template(ct)) {
307 * No template found or the dest of the connection
308 * template is not available.
309 * return *ignored=0 i.e. ICMP and NF_DROP
311 dest = svc->scheduler->schedule(svc, skb);
313 IP_VS_DBG(1, "p-schedule: no dest found.\n");
314 kfree(param.pe_data);
319 if (dst_port == svc->port && svc->port != FTPPORT)
323 * This adds param.pe_data to the template,
324 * and thus param.pe_data will be destroyed
325 * when the template expires */
326 ct = ip_vs_conn_new(¶m, &dest->addr, dport,
327 IP_VS_CONN_F_TEMPLATE, dest, skb->mark);
329 kfree(param.pe_data);
334 ct->timeout = svc->timeout;
336 /* set destination with the found template */
338 kfree(param.pe_data);
342 if (dport == svc->port && dest->port)
345 flags = (svc->flags & IP_VS_SVC_F_ONEPACKET
346 && iph.protocol == IPPROTO_UDP)?
347 IP_VS_CONN_F_ONE_PACKET : 0;
350 * Create a new connection according to the template
352 ip_vs_conn_fill_param(svc->net, svc->af, iph.protocol, &iph.saddr,
353 src_port, &iph.daddr, dst_port, ¶m);
355 cp = ip_vs_conn_new(¶m, &dest->addr, dport, flags, dest, skb->mark);
365 ip_vs_control_add(cp, ct);
368 ip_vs_conn_stats(cp, svc);
374 * IPVS main scheduling function
375 * It selects a server according to the virtual service, and
376 * creates a connection entry.
377 * Protocols supported: TCP, UDP
381 * 1 : protocol tried to schedule (eg. on SYN), found svc but the
382 * svc/scheduler decides that this packet should be accepted with
383 * NF_ACCEPT because it must not be scheduled.
385 * 0 : scheduler can not find destination, so try bypass or
386 * return ICMP and then NF_DROP (ip_vs_leave).
388 * -1 : scheduler tried to schedule but fatal error occurred, eg.
389 * ip_vs_conn_new failure (ENOMEM) or ip_vs_sip_fill_param
390 * failure such as missing Call-ID, ENOMEM on skb_linearize
391 * or pe_data. In this case we should return NF_DROP without
392 * any attempts to send ICMP with ip_vs_leave.
395 ip_vs_schedule(struct ip_vs_service *svc, struct sk_buff *skb,
396 struct ip_vs_proto_data *pd, int *ignored)
398 struct ip_vs_protocol *pp = pd->pp;
399 struct ip_vs_conn *cp = NULL;
400 struct ip_vs_iphdr iph;
401 struct ip_vs_dest *dest;
402 __be16 _ports[2], *pptr;
406 ip_vs_fill_iphdr(svc->af, skb_network_header(skb), &iph);
407 pptr = skb_header_pointer(skb, iph.len, sizeof(_ports), _ports);
412 * FTPDATA needs this check when using local real server.
413 * Never schedule Active FTPDATA connections from real server.
414 * For LVS-NAT they must be already created. For other methods
415 * with persistence the connection is created on SYN+ACK.
417 if (pptr[0] == FTPDATA) {
418 IP_VS_DBG_PKT(12, svc->af, pp, skb, 0,
419 "Not scheduling FTPDATA");
424 * Do not schedule replies from local real server.
426 if ((!skb->dev || skb->dev->flags & IFF_LOOPBACK) &&
427 (cp = pp->conn_in_get(svc->af, skb, &iph, iph.len, 1))) {
428 IP_VS_DBG_PKT(12, svc->af, pp, skb, 0,
429 "Not scheduling reply for existing connection");
430 __ip_vs_conn_put(cp);
437 if (svc->flags & IP_VS_SVC_F_PERSISTENT)
438 return ip_vs_sched_persist(svc, skb, pptr[0], pptr[1], ignored);
443 * Non-persistent service
445 if (!svc->fwmark && pptr[1] != svc->port) {
447 pr_err("Schedule: port zero only supported "
448 "in persistent services, "
449 "check your ipvs configuration\n");
453 dest = svc->scheduler->schedule(svc, skb);
455 IP_VS_DBG(1, "Schedule: no dest found.\n");
459 flags = (svc->flags & IP_VS_SVC_F_ONEPACKET
460 && iph.protocol == IPPROTO_UDP)?
461 IP_VS_CONN_F_ONE_PACKET : 0;
464 * Create a connection entry.
467 struct ip_vs_conn_param p;
469 ip_vs_conn_fill_param(svc->net, svc->af, iph.protocol,
470 &iph.saddr, pptr[0], &iph.daddr, pptr[1],
472 cp = ip_vs_conn_new(&p, &dest->addr,
473 dest->port ? dest->port : pptr[1],
474 flags, dest, skb->mark);
481 IP_VS_DBG_BUF(6, "Schedule fwd:%c c:%s:%u v:%s:%u "
482 "d:%s:%u conn->flags:%X conn->refcnt:%d\n",
484 IP_VS_DBG_ADDR(svc->af, &cp->caddr), ntohs(cp->cport),
485 IP_VS_DBG_ADDR(svc->af, &cp->vaddr), ntohs(cp->vport),
486 IP_VS_DBG_ADDR(svc->af, &cp->daddr), ntohs(cp->dport),
487 cp->flags, atomic_read(&cp->refcnt));
489 ip_vs_conn_stats(cp, svc);
495 * Pass or drop the packet.
496 * Called by ip_vs_in, when the virtual service is available but
497 * no destination is available for a new connection.
499 int ip_vs_leave(struct ip_vs_service *svc, struct sk_buff *skb,
500 struct ip_vs_proto_data *pd)
502 __be16 _ports[2], *pptr;
503 struct ip_vs_iphdr iph;
506 struct netns_ipvs *ipvs;
510 ip_vs_fill_iphdr(svc->af, skb_network_header(skb), &iph);
512 pptr = skb_header_pointer(skb, iph.len, sizeof(_ports), _ports);
514 ip_vs_service_put(svc);
521 #ifdef CONFIG_IP_VS_IPV6
522 if (svc->af == AF_INET6)
523 unicast = ipv6_addr_type(&iph.daddr.in6) & IPV6_ADDR_UNICAST;
526 unicast = (inet_addr_type(net, iph.daddr.ip) == RTN_UNICAST);
528 /* if it is fwmark-based service, the cache_bypass sysctl is up
529 and the destination is a non-local unicast, then create
530 a cache_bypass connection entry */
531 ipvs = net_ipvs(net);
532 if (ipvs->sysctl_cache_bypass && svc->fwmark && unicast) {
534 struct ip_vs_conn *cp;
535 unsigned int flags = (svc->flags & IP_VS_SVC_F_ONEPACKET &&
536 iph.protocol == IPPROTO_UDP)?
537 IP_VS_CONN_F_ONE_PACKET : 0;
538 union nf_inet_addr daddr = { .all = { 0, 0, 0, 0 } };
540 ip_vs_service_put(svc);
542 /* create a new connection entry */
543 IP_VS_DBG(6, "%s(): create a cache_bypass entry\n", __func__);
545 struct ip_vs_conn_param p;
546 ip_vs_conn_fill_param(svc->net, svc->af, iph.protocol,
548 &iph.daddr, pptr[1], &p);
549 cp = ip_vs_conn_new(&p, &daddr, 0,
550 IP_VS_CONN_F_BYPASS | flags,
557 ip_vs_in_stats(cp, skb);
560 cs = ip_vs_set_state(cp, IP_VS_DIR_INPUT, skb, pd);
562 /* transmit the first SYN packet */
563 ret = cp->packet_xmit(skb, cp, pd->pp);
564 /* do not touch skb anymore */
566 atomic_inc(&cp->in_pkts);
573 * When the virtual ftp service is presented, packets destined
574 * for other services on the VIP may get here (except services
575 * listed in the ipvs table), pass the packets, because it is
576 * not ipvs job to decide to drop the packets.
578 if ((svc->port == FTPPORT) && (pptr[1] != FTPPORT)) {
579 ip_vs_service_put(svc);
583 ip_vs_service_put(svc);
586 * Notify the client that the destination is unreachable, and
587 * release the socket buffer.
588 * Since it is in IP layer, the TCP socket is not actually
589 * created, the TCP RST packet cannot be sent, instead that
590 * ICMP_PORT_UNREACH is sent here no matter it is TCP/UDP. --WZ
592 #ifdef CONFIG_IP_VS_IPV6
593 if (svc->af == AF_INET6) {
595 struct net *net = dev_net(skb_dst(skb)->dev);
597 skb->dev = net->loopback_dev;
599 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
602 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
609 static int sysctl_snat_reroute(struct sk_buff *skb)
611 struct netns_ipvs *ipvs = net_ipvs(skb_net(skb));
612 return ipvs->sysctl_snat_reroute;
615 static int sysctl_nat_icmp_send(struct net *net)
617 struct netns_ipvs *ipvs = net_ipvs(net);
618 return ipvs->sysctl_nat_icmp_send;
621 static int sysctl_expire_nodest_conn(struct netns_ipvs *ipvs)
623 return ipvs->sysctl_expire_nodest_conn;
628 static int sysctl_snat_reroute(struct sk_buff *skb) { return 0; }
629 static int sysctl_nat_icmp_send(struct net *net) { return 0; }
630 static int sysctl_expire_nodest_conn(struct netns_ipvs *ipvs) { return 0; }
634 __sum16 ip_vs_checksum_complete(struct sk_buff *skb, int offset)
636 return csum_fold(skb_checksum(skb, offset, skb->len - offset, 0));
639 static inline enum ip_defrag_users ip_vs_defrag_user(unsigned int hooknum)
641 if (NF_INET_LOCAL_IN == hooknum)
642 return IP_DEFRAG_VS_IN;
643 if (NF_INET_FORWARD == hooknum)
644 return IP_DEFRAG_VS_FWD;
645 return IP_DEFRAG_VS_OUT;
648 static inline int ip_vs_gather_frags(struct sk_buff *skb, u_int32_t user)
650 int err = ip_defrag(skb, user);
653 ip_send_check(ip_hdr(skb));
658 #ifdef CONFIG_IP_VS_IPV6
659 static inline int ip_vs_gather_frags_v6(struct sk_buff *skb, u_int32_t user)
661 /* TODO IPv6: Find out what to do here for IPv6 */
666 static int ip_vs_route_me_harder(int af, struct sk_buff *skb)
668 #ifdef CONFIG_IP_VS_IPV6
669 if (af == AF_INET6) {
670 if (sysctl_snat_reroute(skb) && ip6_route_me_harder(skb) != 0)
674 if ((sysctl_snat_reroute(skb) ||
675 skb_rtable(skb)->rt_flags & RTCF_LOCAL) &&
676 ip_route_me_harder(skb, RTN_LOCAL) != 0)
683 * Packet has been made sufficiently writable in caller
684 * - inout: 1=in->out, 0=out->in
686 void ip_vs_nat_icmp(struct sk_buff *skb, struct ip_vs_protocol *pp,
687 struct ip_vs_conn *cp, int inout)
689 struct iphdr *iph = ip_hdr(skb);
690 unsigned int icmp_offset = iph->ihl*4;
691 struct icmphdr *icmph = (struct icmphdr *)(skb_network_header(skb) +
693 struct iphdr *ciph = (struct iphdr *)(icmph + 1);
696 iph->saddr = cp->vaddr.ip;
698 ciph->daddr = cp->vaddr.ip;
701 iph->daddr = cp->daddr.ip;
703 ciph->saddr = cp->daddr.ip;
707 /* the TCP/UDP/SCTP port */
708 if (IPPROTO_TCP == ciph->protocol || IPPROTO_UDP == ciph->protocol ||
709 IPPROTO_SCTP == ciph->protocol) {
710 __be16 *ports = (void *)ciph + ciph->ihl*4;
713 ports[1] = cp->vport;
715 ports[0] = cp->dport;
718 /* And finally the ICMP checksum */
720 icmph->checksum = ip_vs_checksum_complete(skb, icmp_offset);
721 skb->ip_summed = CHECKSUM_UNNECESSARY;
724 IP_VS_DBG_PKT(11, AF_INET, pp, skb, (void *)ciph - (void *)iph,
725 "Forwarding altered outgoing ICMP");
727 IP_VS_DBG_PKT(11, AF_INET, pp, skb, (void *)ciph - (void *)iph,
728 "Forwarding altered incoming ICMP");
731 #ifdef CONFIG_IP_VS_IPV6
732 void ip_vs_nat_icmp_v6(struct sk_buff *skb, struct ip_vs_protocol *pp,
733 struct ip_vs_conn *cp, int inout)
735 struct ipv6hdr *iph = ipv6_hdr(skb);
736 unsigned int icmp_offset = sizeof(struct ipv6hdr);
737 struct icmp6hdr *icmph = (struct icmp6hdr *)(skb_network_header(skb) +
739 struct ipv6hdr *ciph = (struct ipv6hdr *)(icmph + 1);
742 iph->saddr = cp->vaddr.in6;
743 ciph->daddr = cp->vaddr.in6;
745 iph->daddr = cp->daddr.in6;
746 ciph->saddr = cp->daddr.in6;
749 /* the TCP/UDP/SCTP port */
750 if (IPPROTO_TCP == ciph->nexthdr || IPPROTO_UDP == ciph->nexthdr ||
751 IPPROTO_SCTP == ciph->nexthdr) {
752 __be16 *ports = (void *)ciph + sizeof(struct ipv6hdr);
755 ports[1] = cp->vport;
757 ports[0] = cp->dport;
760 /* And finally the ICMP checksum */
761 icmph->icmp6_cksum = ~csum_ipv6_magic(&iph->saddr, &iph->daddr,
762 skb->len - icmp_offset,
764 skb->csum_start = skb_network_header(skb) - skb->head + icmp_offset;
765 skb->csum_offset = offsetof(struct icmp6hdr, icmp6_cksum);
766 skb->ip_summed = CHECKSUM_PARTIAL;
769 IP_VS_DBG_PKT(11, AF_INET6, pp, skb,
770 (void *)ciph - (void *)iph,
771 "Forwarding altered outgoing ICMPv6");
773 IP_VS_DBG_PKT(11, AF_INET6, pp, skb,
774 (void *)ciph - (void *)iph,
775 "Forwarding altered incoming ICMPv6");
779 /* Handle relevant response ICMP messages - forward to the right
782 static int handle_response_icmp(int af, struct sk_buff *skb,
783 union nf_inet_addr *snet,
784 __u8 protocol, struct ip_vs_conn *cp,
785 struct ip_vs_protocol *pp,
786 unsigned int offset, unsigned int ihl)
788 unsigned int verdict = NF_DROP;
790 if (IP_VS_FWD_METHOD(cp) != 0) {
791 pr_err("shouldn't reach here, because the box is on the "
792 "half connection in the tun/dr module.\n");
795 /* Ensure the checksum is correct */
796 if (!skb_csum_unnecessary(skb) && ip_vs_checksum_complete(skb, ihl)) {
797 /* Failed checksum! */
798 IP_VS_DBG_BUF(1, "Forward ICMP: failed checksum from %s!\n",
799 IP_VS_DBG_ADDR(af, snet));
803 if (IPPROTO_TCP == protocol || IPPROTO_UDP == protocol ||
804 IPPROTO_SCTP == protocol)
805 offset += 2 * sizeof(__u16);
806 if (!skb_make_writable(skb, offset))
809 #ifdef CONFIG_IP_VS_IPV6
811 ip_vs_nat_icmp_v6(skb, pp, cp, 1);
814 ip_vs_nat_icmp(skb, pp, cp, 1);
816 if (ip_vs_route_me_harder(af, skb))
819 /* do the statistics and put it back */
820 ip_vs_out_stats(cp, skb);
822 skb->ipvs_property = 1;
823 if (!(cp->flags & IP_VS_CONN_F_NFCT))
826 ip_vs_update_conntrack(skb, cp, 0);
830 __ip_vs_conn_put(cp);
836 * Handle ICMP messages in the inside-to-outside direction (outgoing).
837 * Find any that might be relevant, check against existing connections.
838 * Currently handles error types - unreachable, quench, ttl exceeded.
840 static int ip_vs_out_icmp(struct sk_buff *skb, int *related,
841 unsigned int hooknum)
844 struct icmphdr _icmph, *ic;
845 struct iphdr _ciph, *cih; /* The ip header contained within the ICMP */
846 struct ip_vs_iphdr ciph;
847 struct ip_vs_conn *cp;
848 struct ip_vs_protocol *pp;
849 unsigned int offset, ihl;
850 union nf_inet_addr snet;
854 /* reassemble IP fragments */
855 if (ip_is_fragment(ip_hdr(skb))) {
856 if (ip_vs_gather_frags(skb, ip_vs_defrag_user(hooknum)))
861 offset = ihl = iph->ihl * 4;
862 ic = skb_header_pointer(skb, offset, sizeof(_icmph), &_icmph);
866 IP_VS_DBG(12, "Outgoing ICMP (%d,%d) %pI4->%pI4\n",
867 ic->type, ntohs(icmp_id(ic)),
868 &iph->saddr, &iph->daddr);
871 * Work through seeing if this is for us.
872 * These checks are supposed to be in an order that means easy
873 * things are checked first to speed up processing.... however
874 * this means that some packets will manage to get a long way
875 * down this stack and then be rejected, but that's life.
877 if ((ic->type != ICMP_DEST_UNREACH) &&
878 (ic->type != ICMP_SOURCE_QUENCH) &&
879 (ic->type != ICMP_TIME_EXCEEDED)) {
884 /* Now find the contained IP header */
885 offset += sizeof(_icmph);
886 cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
888 return NF_ACCEPT; /* The packet looks wrong, ignore */
890 pp = ip_vs_proto_get(cih->protocol);
894 /* Is the embedded protocol header present? */
895 if (unlikely(cih->frag_off & htons(IP_OFFSET) &&
899 IP_VS_DBG_PKT(11, AF_INET, pp, skb, offset,
900 "Checking outgoing ICMP for");
902 offset += cih->ihl * 4;
904 ip_vs_fill_iphdr(AF_INET, cih, &ciph);
905 /* The embedded headers contain source and dest in reverse order */
906 cp = pp->conn_out_get(AF_INET, skb, &ciph, offset, 1);
910 snet.ip = iph->saddr;
911 return handle_response_icmp(AF_INET, skb, &snet, cih->protocol, cp,
915 #ifdef CONFIG_IP_VS_IPV6
916 static int ip_vs_out_icmp_v6(struct sk_buff *skb, int *related,
917 unsigned int hooknum)
920 struct icmp6hdr _icmph, *ic;
921 struct ipv6hdr _ciph, *cih; /* The ip header contained
923 struct ip_vs_iphdr ciph;
924 struct ip_vs_conn *cp;
925 struct ip_vs_protocol *pp;
927 union nf_inet_addr snet;
931 /* reassemble IP fragments */
932 if (ipv6_hdr(skb)->nexthdr == IPPROTO_FRAGMENT) {
933 if (ip_vs_gather_frags_v6(skb, ip_vs_defrag_user(hooknum)))
938 offset = sizeof(struct ipv6hdr);
939 ic = skb_header_pointer(skb, offset, sizeof(_icmph), &_icmph);
943 IP_VS_DBG(12, "Outgoing ICMPv6 (%d,%d) %pI6->%pI6\n",
944 ic->icmp6_type, ntohs(icmpv6_id(ic)),
945 &iph->saddr, &iph->daddr);
948 * Work through seeing if this is for us.
949 * These checks are supposed to be in an order that means easy
950 * things are checked first to speed up processing.... however
951 * this means that some packets will manage to get a long way
952 * down this stack and then be rejected, but that's life.
954 if ((ic->icmp6_type != ICMPV6_DEST_UNREACH) &&
955 (ic->icmp6_type != ICMPV6_PKT_TOOBIG) &&
956 (ic->icmp6_type != ICMPV6_TIME_EXCEED)) {
961 /* Now find the contained IP header */
962 offset += sizeof(_icmph);
963 cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
965 return NF_ACCEPT; /* The packet looks wrong, ignore */
967 pp = ip_vs_proto_get(cih->nexthdr);
971 /* Is the embedded protocol header present? */
972 /* TODO: we don't support fragmentation at the moment anyways */
973 if (unlikely(cih->nexthdr == IPPROTO_FRAGMENT && pp->dont_defrag))
976 IP_VS_DBG_PKT(11, AF_INET6, pp, skb, offset,
977 "Checking outgoing ICMPv6 for");
979 offset += sizeof(struct ipv6hdr);
981 ip_vs_fill_iphdr(AF_INET6, cih, &ciph);
982 /* The embedded headers contain source and dest in reverse order */
983 cp = pp->conn_out_get(AF_INET6, skb, &ciph, offset, 1);
987 ipv6_addr_copy(&snet.in6, &iph->saddr);
988 return handle_response_icmp(AF_INET6, skb, &snet, cih->nexthdr, cp,
989 pp, offset, sizeof(struct ipv6hdr));
994 * Check if sctp chunc is ABORT chunk
996 static inline int is_sctp_abort(const struct sk_buff *skb, int nh_len)
998 sctp_chunkhdr_t *sch, schunk;
999 sch = skb_header_pointer(skb, nh_len + sizeof(sctp_sctphdr_t),
1000 sizeof(schunk), &schunk);
1003 if (sch->type == SCTP_CID_ABORT)
1008 static inline int is_tcp_reset(const struct sk_buff *skb, int nh_len)
1010 struct tcphdr _tcph, *th;
1012 th = skb_header_pointer(skb, nh_len, sizeof(_tcph), &_tcph);
1018 /* Handle response packets: rewrite addresses and send away...
1021 handle_response(int af, struct sk_buff *skb, struct ip_vs_proto_data *pd,
1022 struct ip_vs_conn *cp, int ihl)
1024 struct ip_vs_protocol *pp = pd->pp;
1026 IP_VS_DBG_PKT(11, af, pp, skb, 0, "Outgoing packet");
1028 if (!skb_make_writable(skb, ihl))
1031 /* mangle the packet */
1032 if (pp->snat_handler && !pp->snat_handler(skb, pp, cp))
1035 #ifdef CONFIG_IP_VS_IPV6
1037 ipv6_hdr(skb)->saddr = cp->vaddr.in6;
1041 ip_hdr(skb)->saddr = cp->vaddr.ip;
1042 ip_send_check(ip_hdr(skb));
1046 * nf_iterate does not expect change in the skb->dst->dev.
1047 * It looks like it is not fatal to enable this code for hooks
1048 * where our handlers are at the end of the chain list and
1049 * when all next handlers use skb->dst->dev and not outdev.
1050 * It will definitely route properly the inout NAT traffic
1051 * when multiple paths are used.
1054 /* For policy routing, packets originating from this
1055 * machine itself may be routed differently to packets
1056 * passing through. We want this packet to be routed as
1057 * if it came from this machine itself. So re-compute
1058 * the routing information.
1060 if (ip_vs_route_me_harder(af, skb))
1063 IP_VS_DBG_PKT(10, af, pp, skb, 0, "After SNAT");
1065 ip_vs_out_stats(cp, skb);
1066 ip_vs_set_state(cp, IP_VS_DIR_OUTPUT, skb, pd);
1067 skb->ipvs_property = 1;
1068 if (!(cp->flags & IP_VS_CONN_F_NFCT))
1071 ip_vs_update_conntrack(skb, cp, 0);
1085 * Check if outgoing packet belongs to the established ip_vs_conn.
1088 ip_vs_out(unsigned int hooknum, struct sk_buff *skb, int af)
1090 struct net *net = NULL;
1091 struct ip_vs_iphdr iph;
1092 struct ip_vs_protocol *pp;
1093 struct ip_vs_proto_data *pd;
1094 struct ip_vs_conn *cp;
1098 /* Already marked as IPVS request or reply? */
1099 if (skb->ipvs_property)
1102 /* Bad... Do not break raw sockets */
1103 if (unlikely(skb->sk != NULL && hooknum == NF_INET_LOCAL_OUT &&
1105 struct sock *sk = skb->sk;
1106 struct inet_sock *inet = inet_sk(skb->sk);
1108 if (inet && sk->sk_family == PF_INET && inet->nodefrag)
1112 if (unlikely(!skb_dst(skb)))
1116 if (!net_ipvs(net)->enable)
1119 ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
1120 #ifdef CONFIG_IP_VS_IPV6
1121 if (af == AF_INET6) {
1122 if (unlikely(iph.protocol == IPPROTO_ICMPV6)) {
1124 int verdict = ip_vs_out_icmp_v6(skb, &related,
1129 ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
1133 if (unlikely(iph.protocol == IPPROTO_ICMP)) {
1135 int verdict = ip_vs_out_icmp(skb, &related, hooknum);
1139 ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
1142 pd = ip_vs_proto_data_get(net, iph.protocol);
1147 /* reassemble IP fragments */
1148 #ifdef CONFIG_IP_VS_IPV6
1149 if (af == AF_INET6) {
1150 if (ipv6_hdr(skb)->nexthdr == IPPROTO_FRAGMENT) {
1151 if (ip_vs_gather_frags_v6(skb,
1152 ip_vs_defrag_user(hooknum)))
1156 ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
1159 if (unlikely(ip_is_fragment(ip_hdr(skb)) && !pp->dont_defrag)) {
1160 if (ip_vs_gather_frags(skb,
1161 ip_vs_defrag_user(hooknum)))
1164 ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
1168 * Check if the packet belongs to an existing entry
1170 cp = pp->conn_out_get(af, skb, &iph, iph.len, 0);
1173 return handle_response(af, skb, pd, cp, iph.len);
1174 if (sysctl_nat_icmp_send(net) &&
1175 (pp->protocol == IPPROTO_TCP ||
1176 pp->protocol == IPPROTO_UDP ||
1177 pp->protocol == IPPROTO_SCTP)) {
1178 __be16 _ports[2], *pptr;
1180 pptr = skb_header_pointer(skb, iph.len,
1181 sizeof(_ports), _ports);
1183 return NF_ACCEPT; /* Not for me */
1184 if (ip_vs_lookup_real_service(net, af, iph.protocol,
1188 * Notify the real server: there is no
1189 * existing entry if it is not RST
1190 * packet or not TCP packet.
1192 if ((iph.protocol != IPPROTO_TCP &&
1193 iph.protocol != IPPROTO_SCTP)
1194 || ((iph.protocol == IPPROTO_TCP
1195 && !is_tcp_reset(skb, iph.len))
1196 || (iph.protocol == IPPROTO_SCTP
1197 && !is_sctp_abort(skb,
1199 #ifdef CONFIG_IP_VS_IPV6
1200 if (af == AF_INET6) {
1202 dev_net(skb_dst(skb)->dev);
1205 skb->dev = net->loopback_dev;
1207 ICMPV6_DEST_UNREACH,
1208 ICMPV6_PORT_UNREACH,
1214 ICMP_PORT_UNREACH, 0);
1219 IP_VS_DBG_PKT(12, af, pp, skb, 0,
1220 "ip_vs_out: packet continues traversal as normal");
1225 * It is hooked at the NF_INET_FORWARD and NF_INET_LOCAL_IN chain,
1226 * used only for VS/NAT.
1227 * Check if packet is reply for established ip_vs_conn.
1230 ip_vs_reply4(unsigned int hooknum, struct sk_buff *skb,
1231 const struct net_device *in, const struct net_device *out,
1232 int (*okfn)(struct sk_buff *))
1234 return ip_vs_out(hooknum, skb, AF_INET);
1238 * It is hooked at the NF_INET_LOCAL_OUT chain, used only for VS/NAT.
1239 * Check if packet is reply for established ip_vs_conn.
1242 ip_vs_local_reply4(unsigned int hooknum, struct sk_buff *skb,
1243 const struct net_device *in, const struct net_device *out,
1244 int (*okfn)(struct sk_buff *))
1246 unsigned int verdict;
1248 /* Disable BH in LOCAL_OUT until all places are fixed */
1250 verdict = ip_vs_out(hooknum, skb, AF_INET);
1255 #ifdef CONFIG_IP_VS_IPV6
1258 * It is hooked at the NF_INET_FORWARD and NF_INET_LOCAL_IN chain,
1259 * used only for VS/NAT.
1260 * Check if packet is reply for established ip_vs_conn.
1263 ip_vs_reply6(unsigned int hooknum, struct sk_buff *skb,
1264 const struct net_device *in, const struct net_device *out,
1265 int (*okfn)(struct sk_buff *))
1267 return ip_vs_out(hooknum, skb, AF_INET6);
1271 * It is hooked at the NF_INET_LOCAL_OUT chain, used only for VS/NAT.
1272 * Check if packet is reply for established ip_vs_conn.
1275 ip_vs_local_reply6(unsigned int hooknum, struct sk_buff *skb,
1276 const struct net_device *in, const struct net_device *out,
1277 int (*okfn)(struct sk_buff *))
1279 unsigned int verdict;
1281 /* Disable BH in LOCAL_OUT until all places are fixed */
1283 verdict = ip_vs_out(hooknum, skb, AF_INET6);
1291 * Handle ICMP messages in the outside-to-inside direction (incoming).
1292 * Find any that might be relevant, check against existing connections,
1293 * forward to the right destination host if relevant.
1294 * Currently handles error types - unreachable, quench, ttl exceeded.
1297 ip_vs_in_icmp(struct sk_buff *skb, int *related, unsigned int hooknum)
1299 struct net *net = NULL;
1301 struct icmphdr _icmph, *ic;
1302 struct iphdr _ciph, *cih; /* The ip header contained within the ICMP */
1303 struct ip_vs_iphdr ciph;
1304 struct ip_vs_conn *cp;
1305 struct ip_vs_protocol *pp;
1306 struct ip_vs_proto_data *pd;
1307 unsigned int offset, ihl, verdict;
1311 /* reassemble IP fragments */
1312 if (ip_is_fragment(ip_hdr(skb))) {
1313 if (ip_vs_gather_frags(skb, ip_vs_defrag_user(hooknum)))
1318 offset = ihl = iph->ihl * 4;
1319 ic = skb_header_pointer(skb, offset, sizeof(_icmph), &_icmph);
1323 IP_VS_DBG(12, "Incoming ICMP (%d,%d) %pI4->%pI4\n",
1324 ic->type, ntohs(icmp_id(ic)),
1325 &iph->saddr, &iph->daddr);
1328 * Work through seeing if this is for us.
1329 * These checks are supposed to be in an order that means easy
1330 * things are checked first to speed up processing.... however
1331 * this means that some packets will manage to get a long way
1332 * down this stack and then be rejected, but that's life.
1334 if ((ic->type != ICMP_DEST_UNREACH) &&
1335 (ic->type != ICMP_SOURCE_QUENCH) &&
1336 (ic->type != ICMP_TIME_EXCEEDED)) {
1341 /* Now find the contained IP header */
1342 offset += sizeof(_icmph);
1343 cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
1345 return NF_ACCEPT; /* The packet looks wrong, ignore */
1349 pd = ip_vs_proto_data_get(net, cih->protocol);
1354 /* Is the embedded protocol header present? */
1355 if (unlikely(cih->frag_off & htons(IP_OFFSET) &&
1359 IP_VS_DBG_PKT(11, AF_INET, pp, skb, offset,
1360 "Checking incoming ICMP for");
1362 offset += cih->ihl * 4;
1364 ip_vs_fill_iphdr(AF_INET, cih, &ciph);
1365 /* The embedded headers contain source and dest in reverse order */
1366 cp = pp->conn_in_get(AF_INET, skb, &ciph, offset, 1);
1372 /* Ensure the checksum is correct */
1373 if (!skb_csum_unnecessary(skb) && ip_vs_checksum_complete(skb, ihl)) {
1374 /* Failed checksum! */
1375 IP_VS_DBG(1, "Incoming ICMP: failed checksum from %pI4!\n",
1380 /* do the statistics and put it back */
1381 ip_vs_in_stats(cp, skb);
1382 if (IPPROTO_TCP == cih->protocol || IPPROTO_UDP == cih->protocol)
1383 offset += 2 * sizeof(__u16);
1384 verdict = ip_vs_icmp_xmit(skb, cp, pp, offset, hooknum);
1387 __ip_vs_conn_put(cp);
1392 #ifdef CONFIG_IP_VS_IPV6
1394 ip_vs_in_icmp_v6(struct sk_buff *skb, int *related, unsigned int hooknum)
1396 struct net *net = NULL;
1397 struct ipv6hdr *iph;
1398 struct icmp6hdr _icmph, *ic;
1399 struct ipv6hdr _ciph, *cih; /* The ip header contained
1401 struct ip_vs_iphdr ciph;
1402 struct ip_vs_conn *cp;
1403 struct ip_vs_protocol *pp;
1404 struct ip_vs_proto_data *pd;
1405 unsigned int offset, verdict;
1409 /* reassemble IP fragments */
1410 if (ipv6_hdr(skb)->nexthdr == IPPROTO_FRAGMENT) {
1411 if (ip_vs_gather_frags_v6(skb, ip_vs_defrag_user(hooknum)))
1415 iph = ipv6_hdr(skb);
1416 offset = sizeof(struct ipv6hdr);
1417 ic = skb_header_pointer(skb, offset, sizeof(_icmph), &_icmph);
1421 IP_VS_DBG(12, "Incoming ICMPv6 (%d,%d) %pI6->%pI6\n",
1422 ic->icmp6_type, ntohs(icmpv6_id(ic)),
1423 &iph->saddr, &iph->daddr);
1426 * Work through seeing if this is for us.
1427 * These checks are supposed to be in an order that means easy
1428 * things are checked first to speed up processing.... however
1429 * this means that some packets will manage to get a long way
1430 * down this stack and then be rejected, but that's life.
1432 if ((ic->icmp6_type != ICMPV6_DEST_UNREACH) &&
1433 (ic->icmp6_type != ICMPV6_PKT_TOOBIG) &&
1434 (ic->icmp6_type != ICMPV6_TIME_EXCEED)) {
1439 /* Now find the contained IP header */
1440 offset += sizeof(_icmph);
1441 cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
1443 return NF_ACCEPT; /* The packet looks wrong, ignore */
1446 pd = ip_vs_proto_data_get(net, cih->nexthdr);
1451 /* Is the embedded protocol header present? */
1452 /* TODO: we don't support fragmentation at the moment anyways */
1453 if (unlikely(cih->nexthdr == IPPROTO_FRAGMENT && pp->dont_defrag))
1456 IP_VS_DBG_PKT(11, AF_INET6, pp, skb, offset,
1457 "Checking incoming ICMPv6 for");
1459 offset += sizeof(struct ipv6hdr);
1461 ip_vs_fill_iphdr(AF_INET6, cih, &ciph);
1462 /* The embedded headers contain source and dest in reverse order */
1463 cp = pp->conn_in_get(AF_INET6, skb, &ciph, offset, 1);
1467 /* do the statistics and put it back */
1468 ip_vs_in_stats(cp, skb);
1469 if (IPPROTO_TCP == cih->nexthdr || IPPROTO_UDP == cih->nexthdr ||
1470 IPPROTO_SCTP == cih->nexthdr)
1471 offset += 2 * sizeof(__u16);
1472 verdict = ip_vs_icmp_xmit_v6(skb, cp, pp, offset, hooknum);
1474 __ip_vs_conn_put(cp);
1482 * Check if it's for virtual services, look it up,
1483 * and send it on its way...
1486 ip_vs_in(unsigned int hooknum, struct sk_buff *skb, int af)
1489 struct ip_vs_iphdr iph;
1490 struct ip_vs_protocol *pp;
1491 struct ip_vs_proto_data *pd;
1492 struct ip_vs_conn *cp;
1493 int ret, restart, pkts;
1494 struct netns_ipvs *ipvs;
1496 /* Already marked as IPVS request or reply? */
1497 if (skb->ipvs_property)
1502 * - remote client: only PACKET_HOST
1503 * - route: used for struct net when skb->dev is unset
1505 if (unlikely((skb->pkt_type != PACKET_HOST &&
1506 hooknum != NF_INET_LOCAL_OUT) ||
1508 ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
1509 IP_VS_DBG_BUF(12, "packet type=%d proto=%d daddr=%s"
1510 " ignored in hook %u\n",
1511 skb->pkt_type, iph.protocol,
1512 IP_VS_DBG_ADDR(af, &iph.daddr), hooknum);
1515 /* ipvs enabled in this netns ? */
1517 if (!net_ipvs(net)->enable)
1520 ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
1522 /* Bad... Do not break raw sockets */
1523 if (unlikely(skb->sk != NULL && hooknum == NF_INET_LOCAL_OUT &&
1525 struct sock *sk = skb->sk;
1526 struct inet_sock *inet = inet_sk(skb->sk);
1528 if (inet && sk->sk_family == PF_INET && inet->nodefrag)
1532 #ifdef CONFIG_IP_VS_IPV6
1533 if (af == AF_INET6) {
1534 if (unlikely(iph.protocol == IPPROTO_ICMPV6)) {
1536 int verdict = ip_vs_in_icmp_v6(skb, &related, hooknum);
1540 ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
1544 if (unlikely(iph.protocol == IPPROTO_ICMP)) {
1546 int verdict = ip_vs_in_icmp(skb, &related, hooknum);
1550 ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
1553 /* Protocol supported? */
1554 pd = ip_vs_proto_data_get(net, iph.protocol);
1559 * Check if the packet belongs to an existing connection entry
1561 cp = pp->conn_in_get(af, skb, &iph, iph.len, 0);
1563 if (unlikely(!cp)) {
1566 if (!pp->conn_schedule(af, skb, pd, &v, &cp))
1570 if (unlikely(!cp)) {
1571 /* sorry, all this trouble for a no-hit :) */
1572 IP_VS_DBG_PKT(12, af, pp, skb, 0,
1573 "ip_vs_in: packet continues traversal as normal");
1577 IP_VS_DBG_PKT(11, af, pp, skb, 0, "Incoming packet");
1578 ipvs = net_ipvs(net);
1579 /* Check the server status */
1580 if (cp->dest && !(cp->dest->flags & IP_VS_DEST_F_AVAILABLE)) {
1581 /* the destination server is not available */
1583 if (sysctl_expire_nodest_conn(ipvs)) {
1584 /* try to expire the connection immediately */
1585 ip_vs_conn_expire_now(cp);
1587 /* don't restart its timer, and silently
1589 __ip_vs_conn_put(cp);
1593 ip_vs_in_stats(cp, skb);
1594 restart = ip_vs_set_state(cp, IP_VS_DIR_INPUT, skb, pd);
1595 if (cp->packet_xmit)
1596 ret = cp->packet_xmit(skb, cp, pp);
1597 /* do not touch skb anymore */
1599 IP_VS_DBG_RL("warning: packet_xmit is null");
1603 /* Increase its packet counter and check if it is needed
1604 * to be synchronized
1606 * Sync connection if it is about to close to
1607 * encorage the standby servers to update the connections timeout
1609 * For ONE_PKT let ip_vs_sync_conn() do the filter work.
1612 if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
1613 pkts = sysctl_sync_threshold(ipvs);
1615 pkts = atomic_add_return(1, &cp->in_pkts);
1617 if ((ipvs->sync_state & IP_VS_STATE_MASTER) &&
1618 cp->protocol == IPPROTO_SCTP) {
1619 if ((cp->state == IP_VS_SCTP_S_ESTABLISHED &&
1620 (pkts % sysctl_sync_period(ipvs)
1621 == sysctl_sync_threshold(ipvs))) ||
1622 (cp->old_state != cp->state &&
1623 ((cp->state == IP_VS_SCTP_S_CLOSED) ||
1624 (cp->state == IP_VS_SCTP_S_SHUT_ACK_CLI) ||
1625 (cp->state == IP_VS_SCTP_S_SHUT_ACK_SER)))) {
1626 ip_vs_sync_conn(net, cp);
1631 /* Keep this block last: TCP and others with pp->num_states <= 1 */
1632 else if ((ipvs->sync_state & IP_VS_STATE_MASTER) &&
1633 (((cp->protocol != IPPROTO_TCP ||
1634 cp->state == IP_VS_TCP_S_ESTABLISHED) &&
1635 (pkts % sysctl_sync_period(ipvs)
1636 == sysctl_sync_threshold(ipvs))) ||
1637 ((cp->protocol == IPPROTO_TCP) && (cp->old_state != cp->state) &&
1638 ((cp->state == IP_VS_TCP_S_FIN_WAIT) ||
1639 (cp->state == IP_VS_TCP_S_CLOSE) ||
1640 (cp->state == IP_VS_TCP_S_CLOSE_WAIT) ||
1641 (cp->state == IP_VS_TCP_S_TIME_WAIT)))))
1642 ip_vs_sync_conn(net, cp);
1644 cp->old_state = cp->state;
1651 * AF_INET handler in NF_INET_LOCAL_IN chain
1652 * Schedule and forward packets from remote clients
1655 ip_vs_remote_request4(unsigned int hooknum, struct sk_buff *skb,
1656 const struct net_device *in,
1657 const struct net_device *out,
1658 int (*okfn)(struct sk_buff *))
1660 return ip_vs_in(hooknum, skb, AF_INET);
1664 * AF_INET handler in NF_INET_LOCAL_OUT chain
1665 * Schedule and forward packets from local clients
1668 ip_vs_local_request4(unsigned int hooknum, struct sk_buff *skb,
1669 const struct net_device *in, const struct net_device *out,
1670 int (*okfn)(struct sk_buff *))
1672 unsigned int verdict;
1674 /* Disable BH in LOCAL_OUT until all places are fixed */
1676 verdict = ip_vs_in(hooknum, skb, AF_INET);
1681 #ifdef CONFIG_IP_VS_IPV6
1684 * AF_INET6 handler in NF_INET_LOCAL_IN chain
1685 * Schedule and forward packets from remote clients
1688 ip_vs_remote_request6(unsigned int hooknum, struct sk_buff *skb,
1689 const struct net_device *in,
1690 const struct net_device *out,
1691 int (*okfn)(struct sk_buff *))
1693 return ip_vs_in(hooknum, skb, AF_INET6);
1697 * AF_INET6 handler in NF_INET_LOCAL_OUT chain
1698 * Schedule and forward packets from local clients
1701 ip_vs_local_request6(unsigned int hooknum, struct sk_buff *skb,
1702 const struct net_device *in, const struct net_device *out,
1703 int (*okfn)(struct sk_buff *))
1705 unsigned int verdict;
1707 /* Disable BH in LOCAL_OUT until all places are fixed */
1709 verdict = ip_vs_in(hooknum, skb, AF_INET6);
1718 * It is hooked at the NF_INET_FORWARD chain, in order to catch ICMP
1719 * related packets destined for 0.0.0.0/0.
1720 * When fwmark-based virtual service is used, such as transparent
1721 * cache cluster, TCP packets can be marked and routed to ip_vs_in,
1722 * but ICMP destined for 0.0.0.0/0 cannot not be easily marked and
1723 * sent to ip_vs_in_icmp. So, catch them at the NF_INET_FORWARD chain
1724 * and send them to ip_vs_in_icmp.
1727 ip_vs_forward_icmp(unsigned int hooknum, struct sk_buff *skb,
1728 const struct net_device *in, const struct net_device *out,
1729 int (*okfn)(struct sk_buff *))
1734 if (ip_hdr(skb)->protocol != IPPROTO_ICMP)
1737 /* ipvs enabled in this netns ? */
1739 if (!net_ipvs(net)->enable)
1742 return ip_vs_in_icmp(skb, &r, hooknum);
1745 #ifdef CONFIG_IP_VS_IPV6
1747 ip_vs_forward_icmp_v6(unsigned int hooknum, struct sk_buff *skb,
1748 const struct net_device *in, const struct net_device *out,
1749 int (*okfn)(struct sk_buff *))
1754 if (ipv6_hdr(skb)->nexthdr != IPPROTO_ICMPV6)
1757 /* ipvs enabled in this netns ? */
1759 if (!net_ipvs(net)->enable)
1762 return ip_vs_in_icmp_v6(skb, &r, hooknum);
1767 static struct nf_hook_ops ip_vs_ops[] __read_mostly = {
1768 /* After packet filtering, change source only for VS/NAT */
1770 .hook = ip_vs_reply4,
1771 .owner = THIS_MODULE,
1773 .hooknum = NF_INET_LOCAL_IN,
1774 .priority = NF_IP_PRI_NAT_SRC - 2,
1776 /* After packet filtering, forward packet through VS/DR, VS/TUN,
1777 * or VS/NAT(change destination), so that filtering rules can be
1778 * applied to IPVS. */
1780 .hook = ip_vs_remote_request4,
1781 .owner = THIS_MODULE,
1783 .hooknum = NF_INET_LOCAL_IN,
1784 .priority = NF_IP_PRI_NAT_SRC - 1,
1786 /* Before ip_vs_in, change source only for VS/NAT */
1788 .hook = ip_vs_local_reply4,
1789 .owner = THIS_MODULE,
1791 .hooknum = NF_INET_LOCAL_OUT,
1792 .priority = NF_IP_PRI_NAT_DST + 1,
1794 /* After mangle, schedule and forward local requests */
1796 .hook = ip_vs_local_request4,
1797 .owner = THIS_MODULE,
1799 .hooknum = NF_INET_LOCAL_OUT,
1800 .priority = NF_IP_PRI_NAT_DST + 2,
1802 /* After packet filtering (but before ip_vs_out_icmp), catch icmp
1803 * destined for 0.0.0.0/0, which is for incoming IPVS connections */
1805 .hook = ip_vs_forward_icmp,
1806 .owner = THIS_MODULE,
1808 .hooknum = NF_INET_FORWARD,
1811 /* After packet filtering, change source only for VS/NAT */
1813 .hook = ip_vs_reply4,
1814 .owner = THIS_MODULE,
1816 .hooknum = NF_INET_FORWARD,
1819 #ifdef CONFIG_IP_VS_IPV6
1820 /* After packet filtering, change source only for VS/NAT */
1822 .hook = ip_vs_reply6,
1823 .owner = THIS_MODULE,
1825 .hooknum = NF_INET_LOCAL_IN,
1826 .priority = NF_IP6_PRI_NAT_SRC - 2,
1828 /* After packet filtering, forward packet through VS/DR, VS/TUN,
1829 * or VS/NAT(change destination), so that filtering rules can be
1830 * applied to IPVS. */
1832 .hook = ip_vs_remote_request6,
1833 .owner = THIS_MODULE,
1835 .hooknum = NF_INET_LOCAL_IN,
1836 .priority = NF_IP6_PRI_NAT_SRC - 1,
1838 /* Before ip_vs_in, change source only for VS/NAT */
1840 .hook = ip_vs_local_reply6,
1841 .owner = THIS_MODULE,
1843 .hooknum = NF_INET_LOCAL_OUT,
1844 .priority = NF_IP6_PRI_NAT_DST + 1,
1846 /* After mangle, schedule and forward local requests */
1848 .hook = ip_vs_local_request6,
1849 .owner = THIS_MODULE,
1851 .hooknum = NF_INET_LOCAL_OUT,
1852 .priority = NF_IP6_PRI_NAT_DST + 2,
1854 /* After packet filtering (but before ip_vs_out_icmp), catch icmp
1855 * destined for 0.0.0.0/0, which is for incoming IPVS connections */
1857 .hook = ip_vs_forward_icmp_v6,
1858 .owner = THIS_MODULE,
1860 .hooknum = NF_INET_FORWARD,
1863 /* After packet filtering, change source only for VS/NAT */
1865 .hook = ip_vs_reply6,
1866 .owner = THIS_MODULE,
1868 .hooknum = NF_INET_FORWARD,
1874 * Initialize IP Virtual Server netns mem.
1876 static int __net_init __ip_vs_init(struct net *net)
1878 struct netns_ipvs *ipvs;
1880 ipvs = net_generic(net, ip_vs_net_id);
1882 pr_err("%s(): no memory.\n", __func__);
1885 /* Hold the beast until a service is registerd */
1888 /* Counters used for creating unique names */
1889 ipvs->gen = atomic_read(&ipvs_netns_cnt);
1890 atomic_inc(&ipvs_netns_cnt);
1893 if (ip_vs_estimator_net_init(net) < 0)
1894 goto estimator_fail;
1896 if (ip_vs_control_net_init(net) < 0)
1899 if (ip_vs_protocol_net_init(net) < 0)
1902 if (ip_vs_app_net_init(net) < 0)
1905 if (ip_vs_conn_net_init(net) < 0)
1908 if (ip_vs_sync_net_init(net) < 0)
1911 printk(KERN_INFO "IPVS: Creating netns size=%zu id=%d\n",
1912 sizeof(struct netns_ipvs), ipvs->gen);
1919 ip_vs_conn_net_cleanup(net);
1921 ip_vs_app_net_cleanup(net);
1923 ip_vs_protocol_net_cleanup(net);
1925 ip_vs_control_net_cleanup(net);
1927 ip_vs_estimator_net_cleanup(net);
1932 static void __net_exit __ip_vs_cleanup(struct net *net)
1934 ip_vs_service_net_cleanup(net); /* ip_vs_flush() with locks */
1935 ip_vs_conn_net_cleanup(net);
1936 ip_vs_app_net_cleanup(net);
1937 ip_vs_protocol_net_cleanup(net);
1938 ip_vs_control_net_cleanup(net);
1939 ip_vs_estimator_net_cleanup(net);
1940 IP_VS_DBG(2, "ipvs netns %d released\n", net_ipvs(net)->gen);
1943 static void __net_exit __ip_vs_dev_cleanup(struct net *net)
1946 net_ipvs(net)->enable = 0; /* Disable packet reception */
1948 ip_vs_sync_net_cleanup(net);
1952 static struct pernet_operations ipvs_core_ops = {
1953 .init = __ip_vs_init,
1954 .exit = __ip_vs_cleanup,
1955 .id = &ip_vs_net_id,
1956 .size = sizeof(struct netns_ipvs),
1959 static struct pernet_operations ipvs_core_dev_ops = {
1960 .exit = __ip_vs_dev_cleanup,
1964 * Initialize IP Virtual Server
1966 static int __init ip_vs_init(void)
1970 ret = ip_vs_control_init();
1972 pr_err("can't setup control.\n");
1976 ip_vs_protocol_init();
1978 ret = ip_vs_conn_init();
1980 pr_err("can't setup connection table.\n");
1981 goto cleanup_protocol;
1984 ret = register_pernet_subsys(&ipvs_core_ops); /* Alloc ip_vs struct */
1988 ret = register_pernet_device(&ipvs_core_dev_ops);
1992 ret = nf_register_hooks(ip_vs_ops, ARRAY_SIZE(ip_vs_ops));
1994 pr_err("can't register hooks.\n");
1998 pr_info("ipvs loaded.\n");
2003 unregister_pernet_device(&ipvs_core_dev_ops);
2005 unregister_pernet_subsys(&ipvs_core_ops);
2007 ip_vs_conn_cleanup();
2009 ip_vs_protocol_cleanup();
2010 ip_vs_control_cleanup();
2015 static void __exit ip_vs_cleanup(void)
2017 nf_unregister_hooks(ip_vs_ops, ARRAY_SIZE(ip_vs_ops));
2018 unregister_pernet_device(&ipvs_core_dev_ops);
2019 unregister_pernet_subsys(&ipvs_core_ops); /* free ip_vs struct */
2020 ip_vs_conn_cleanup();
2021 ip_vs_protocol_cleanup();
2022 ip_vs_control_cleanup();
2023 pr_info("ipvs unloaded.\n");
2026 module_init(ip_vs_init);
2027 module_exit(ip_vs_cleanup);
2028 MODULE_LICENSE("GPL");