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 static int ip_vs_net_id __read_mostly;
73 /* netns cnt used for uniqueness */
74 static atomic_t ipvs_netns_cnt = ATOMIC_INIT(0);
76 /* ID used in ICMP lookups */
77 #define icmp_id(icmph) (((icmph)->un).echo.id)
78 #define icmpv6_id(icmph) (icmph->icmp6_dataun.u_echo.identifier)
80 const char *ip_vs_proto_name(unsigned int proto)
95 #ifdef CONFIG_IP_VS_IPV6
100 sprintf(buf, "IP_%d", proto);
105 void ip_vs_init_hash_table(struct list_head *table, int rows)
108 INIT_LIST_HEAD(&table[rows]);
112 ip_vs_in_stats(struct ip_vs_conn *cp, struct sk_buff *skb)
114 struct ip_vs_dest *dest = cp->dest;
115 struct netns_ipvs *ipvs = net_ipvs(skb_net(skb));
117 if (dest && (dest->flags & IP_VS_DEST_F_AVAILABLE)) {
118 struct ip_vs_cpu_stats *s;
120 s = this_cpu_ptr(dest->stats.cpustats);
122 u64_stats_update_begin(&s->syncp);
123 s->ustats.inbytes += skb->len;
124 u64_stats_update_end(&s->syncp);
126 s = this_cpu_ptr(dest->svc->stats.cpustats);
128 u64_stats_update_begin(&s->syncp);
129 s->ustats.inbytes += skb->len;
130 u64_stats_update_end(&s->syncp);
132 s = this_cpu_ptr(ipvs->tot_stats.cpustats);
134 u64_stats_update_begin(&s->syncp);
135 s->ustats.inbytes += skb->len;
136 u64_stats_update_end(&s->syncp);
142 ip_vs_out_stats(struct ip_vs_conn *cp, struct sk_buff *skb)
144 struct ip_vs_dest *dest = cp->dest;
145 struct netns_ipvs *ipvs = net_ipvs(skb_net(skb));
147 if (dest && (dest->flags & IP_VS_DEST_F_AVAILABLE)) {
148 struct ip_vs_cpu_stats *s;
150 s = this_cpu_ptr(dest->stats.cpustats);
152 u64_stats_update_begin(&s->syncp);
153 s->ustats.outbytes += skb->len;
154 u64_stats_update_end(&s->syncp);
156 s = this_cpu_ptr(dest->svc->stats.cpustats);
158 u64_stats_update_begin(&s->syncp);
159 s->ustats.outbytes += skb->len;
160 u64_stats_update_end(&s->syncp);
162 s = this_cpu_ptr(ipvs->tot_stats.cpustats);
164 u64_stats_update_begin(&s->syncp);
165 s->ustats.outbytes += skb->len;
166 u64_stats_update_end(&s->syncp);
172 ip_vs_conn_stats(struct ip_vs_conn *cp, struct ip_vs_service *svc)
174 struct netns_ipvs *ipvs = net_ipvs(svc->net);
175 struct ip_vs_cpu_stats *s;
177 s = this_cpu_ptr(cp->dest->stats.cpustats);
180 s = this_cpu_ptr(svc->stats.cpustats);
183 s = this_cpu_ptr(ipvs->tot_stats.cpustats);
189 ip_vs_set_state(struct ip_vs_conn *cp, int direction,
190 const struct sk_buff *skb,
191 struct ip_vs_proto_data *pd)
193 if (likely(pd->pp->state_transition))
194 pd->pp->state_transition(cp, direction, skb, pd);
198 ip_vs_conn_fill_param_persist(const struct ip_vs_service *svc,
199 struct sk_buff *skb, int protocol,
200 const union nf_inet_addr *caddr, __be16 cport,
201 const union nf_inet_addr *vaddr, __be16 vport,
202 struct ip_vs_conn_param *p)
204 ip_vs_conn_fill_param(svc->net, svc->af, protocol, caddr, cport, vaddr,
206 p->pe = rcu_dereference(svc->pe);
207 if (p->pe && p->pe->fill_param)
208 return p->pe->fill_param(p, skb);
214 * IPVS persistent scheduling function
215 * It creates a connection entry according to its template if exists,
216 * or selects a server and creates a connection entry plus a template.
217 * Locking: we are svc user (svc->refcnt), so we hold all dests too
218 * Protocols supported: TCP, UDP
220 static struct ip_vs_conn *
221 ip_vs_sched_persist(struct ip_vs_service *svc,
222 struct sk_buff *skb, __be16 src_port, __be16 dst_port,
223 int *ignored, struct ip_vs_iphdr *iph)
225 struct ip_vs_conn *cp = NULL;
226 struct ip_vs_dest *dest;
227 struct ip_vs_conn *ct;
228 __be16 dport = 0; /* destination port to forward */
230 struct ip_vs_conn_param param;
231 const union nf_inet_addr fwmark = { .ip = htonl(svc->fwmark) };
232 union nf_inet_addr snet; /* source network of the client,
235 /* Mask saddr with the netmask to adjust template granularity */
236 #ifdef CONFIG_IP_VS_IPV6
237 if (svc->af == AF_INET6)
238 ipv6_addr_prefix(&snet.in6, &iph->saddr.in6, svc->netmask);
241 snet.ip = iph->saddr.ip & svc->netmask;
243 IP_VS_DBG_BUF(6, "p-schedule: src %s:%u dest %s:%u "
245 IP_VS_DBG_ADDR(svc->af, &iph->saddr), ntohs(src_port),
246 IP_VS_DBG_ADDR(svc->af, &iph->daddr), ntohs(dst_port),
247 IP_VS_DBG_ADDR(svc->af, &snet));
250 * As far as we know, FTP is a very complicated network protocol, and
251 * it uses control connection and data connections. For active FTP,
252 * FTP server initialize data connection to the client, its source port
253 * is often 20. For passive FTP, FTP server tells the clients the port
254 * that it passively listens to, and the client issues the data
255 * connection. In the tunneling or direct routing mode, the load
256 * balancer is on the client-to-server half of connection, the port
257 * number is unknown to the load balancer. So, a conn template like
258 * <caddr, 0, vaddr, 0, daddr, 0> is created for persistent FTP
259 * service, and a template like <caddr, 0, vaddr, vport, daddr, dport>
260 * is created for other persistent services.
263 int protocol = iph->protocol;
264 const union nf_inet_addr *vaddr = &iph->daddr;
267 if (dst_port == svc->port) {
269 * <protocol, caddr, 0, vaddr, vport, daddr, dport>
271 * <protocol, caddr, 0, vaddr, 0, daddr, 0>
273 if (svc->port != FTPPORT)
276 /* Note: persistent fwmark-based services and
277 * persistent port zero service are handled here.
279 * <IPPROTO_IP,caddr,0,fwmark,0,daddr,0>
280 * port zero template:
281 * <protocol,caddr,0,vaddr,0,daddr,0>
284 protocol = IPPROTO_IP;
288 /* return *ignored = -1 so NF_DROP can be used */
289 if (ip_vs_conn_fill_param_persist(svc, skb, protocol, &snet, 0,
290 vaddr, vport, ¶m) < 0) {
296 /* Check if a template already exists */
297 ct = ip_vs_ct_in_get(¶m);
298 if (!ct || !ip_vs_check_template(ct)) {
299 struct ip_vs_scheduler *sched;
302 * No template found or the dest of the connection
303 * template is not available.
304 * return *ignored=0 i.e. ICMP and NF_DROP
306 sched = rcu_dereference(svc->scheduler);
307 dest = sched->schedule(svc, skb);
309 IP_VS_DBG(1, "p-schedule: no dest found.\n");
310 kfree(param.pe_data);
315 if (dst_port == svc->port && svc->port != FTPPORT)
319 * This adds param.pe_data to the template,
320 * and thus param.pe_data will be destroyed
321 * when the template expires */
322 ct = ip_vs_conn_new(¶m, &dest->addr, dport,
323 IP_VS_CONN_F_TEMPLATE, dest, skb->mark);
325 kfree(param.pe_data);
330 ct->timeout = svc->timeout;
332 /* set destination with the found template */
334 kfree(param.pe_data);
338 if (dport == svc->port && dest->port)
341 flags = (svc->flags & IP_VS_SVC_F_ONEPACKET
342 && iph->protocol == IPPROTO_UDP) ?
343 IP_VS_CONN_F_ONE_PACKET : 0;
346 * Create a new connection according to the template
348 ip_vs_conn_fill_param(svc->net, svc->af, iph->protocol, &iph->saddr,
349 src_port, &iph->daddr, dst_port, ¶m);
351 cp = ip_vs_conn_new(¶m, &dest->addr, dport, flags, dest, skb->mark);
361 ip_vs_control_add(cp, ct);
364 ip_vs_conn_stats(cp, svc);
370 * IPVS main scheduling function
371 * It selects a server according to the virtual service, and
372 * creates a connection entry.
373 * Protocols supported: TCP, UDP
377 * 1 : protocol tried to schedule (eg. on SYN), found svc but the
378 * svc/scheduler decides that this packet should be accepted with
379 * NF_ACCEPT because it must not be scheduled.
381 * 0 : scheduler can not find destination, so try bypass or
382 * return ICMP and then NF_DROP (ip_vs_leave).
384 * -1 : scheduler tried to schedule but fatal error occurred, eg.
385 * ip_vs_conn_new failure (ENOMEM) or ip_vs_sip_fill_param
386 * failure such as missing Call-ID, ENOMEM on skb_linearize
387 * or pe_data. In this case we should return NF_DROP without
388 * any attempts to send ICMP with ip_vs_leave.
391 ip_vs_schedule(struct ip_vs_service *svc, struct sk_buff *skb,
392 struct ip_vs_proto_data *pd, int *ignored,
393 struct ip_vs_iphdr *iph)
395 struct ip_vs_protocol *pp = pd->pp;
396 struct ip_vs_conn *cp = NULL;
397 struct ip_vs_scheduler *sched;
398 struct ip_vs_dest *dest;
399 __be16 _ports[2], *pptr;
404 * IPv6 frags, only the first hit here.
406 pptr = frag_safe_skb_hp(skb, iph->len, sizeof(_ports), _ports, iph);
411 * FTPDATA needs this check when using local real server.
412 * Never schedule Active FTPDATA connections from real server.
413 * For LVS-NAT they must be already created. For other methods
414 * with persistence the connection is created on SYN+ACK.
416 if (pptr[0] == FTPDATA) {
417 IP_VS_DBG_PKT(12, svc->af, pp, skb, 0,
418 "Not scheduling FTPDATA");
423 * Do not schedule replies from local real server.
425 if ((!skb->dev || skb->dev->flags & IFF_LOOPBACK) &&
426 (cp = pp->conn_in_get(svc->af, skb, iph, 1))) {
427 IP_VS_DBG_PKT(12, svc->af, pp, skb, 0,
428 "Not scheduling reply for existing connection");
429 __ip_vs_conn_put(cp);
436 if (svc->flags & IP_VS_SVC_F_PERSISTENT)
437 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 sched = rcu_dereference(svc->scheduler);
454 dest = sched->schedule(svc, skb);
456 IP_VS_DBG(1, "Schedule: no dest found.\n");
460 flags = (svc->flags & IP_VS_SVC_F_ONEPACKET
461 && iph->protocol == IPPROTO_UDP) ?
462 IP_VS_CONN_F_ONE_PACKET : 0;
465 * Create a connection entry.
468 struct ip_vs_conn_param p;
470 ip_vs_conn_fill_param(svc->net, svc->af, iph->protocol,
471 &iph->saddr, pptr[0], &iph->daddr,
473 cp = ip_vs_conn_new(&p, &dest->addr,
474 dest->port ? dest->port : pptr[1],
475 flags, dest, skb->mark);
482 IP_VS_DBG_BUF(6, "Schedule fwd:%c c:%s:%u v:%s:%u "
483 "d:%s:%u conn->flags:%X conn->refcnt:%d\n",
485 IP_VS_DBG_ADDR(svc->af, &cp->caddr), ntohs(cp->cport),
486 IP_VS_DBG_ADDR(svc->af, &cp->vaddr), ntohs(cp->vport),
487 IP_VS_DBG_ADDR(svc->af, &cp->daddr), ntohs(cp->dport),
488 cp->flags, atomic_read(&cp->refcnt));
490 ip_vs_conn_stats(cp, svc);
496 * Pass or drop the packet.
497 * Called by ip_vs_in, when the virtual service is available but
498 * no destination is available for a new connection.
500 int ip_vs_leave(struct ip_vs_service *svc, struct sk_buff *skb,
501 struct ip_vs_proto_data *pd, struct ip_vs_iphdr *iph)
503 __be16 _ports[2], *pptr;
506 struct netns_ipvs *ipvs;
510 pptr = frag_safe_skb_hp(skb, iph->len, sizeof(_ports), _ports, iph);
518 #ifdef CONFIG_IP_VS_IPV6
519 if (svc->af == AF_INET6)
520 unicast = ipv6_addr_type(&iph->daddr.in6) & IPV6_ADDR_UNICAST;
523 unicast = (inet_addr_type(net, iph->daddr.ip) == RTN_UNICAST);
525 /* if it is fwmark-based service, the cache_bypass sysctl is up
526 and the destination is a non-local unicast, then create
527 a cache_bypass connection entry */
528 ipvs = net_ipvs(net);
529 if (ipvs->sysctl_cache_bypass && svc->fwmark && unicast) {
531 struct ip_vs_conn *cp;
532 unsigned int flags = (svc->flags & IP_VS_SVC_F_ONEPACKET &&
533 iph->protocol == IPPROTO_UDP) ?
534 IP_VS_CONN_F_ONE_PACKET : 0;
535 union nf_inet_addr daddr = { .all = { 0, 0, 0, 0 } };
537 /* create a new connection entry */
538 IP_VS_DBG(6, "%s(): create a cache_bypass entry\n", __func__);
540 struct ip_vs_conn_param p;
541 ip_vs_conn_fill_param(svc->net, svc->af, iph->protocol,
542 &iph->saddr, pptr[0],
543 &iph->daddr, pptr[1], &p);
544 cp = ip_vs_conn_new(&p, &daddr, 0,
545 IP_VS_CONN_F_BYPASS | flags,
552 ip_vs_in_stats(cp, skb);
555 ip_vs_set_state(cp, IP_VS_DIR_INPUT, skb, pd);
557 /* transmit the first SYN packet */
558 ret = cp->packet_xmit(skb, cp, pd->pp, iph);
559 /* do not touch skb anymore */
561 atomic_inc(&cp->in_pkts);
568 * When the virtual ftp service is presented, packets destined
569 * for other services on the VIP may get here (except services
570 * listed in the ipvs table), pass the packets, because it is
571 * not ipvs job to decide to drop the packets.
573 if ((svc->port == FTPPORT) && (pptr[1] != FTPPORT))
577 * Notify the client that the destination is unreachable, and
578 * release the socket buffer.
579 * Since it is in IP layer, the TCP socket is not actually
580 * created, the TCP RST packet cannot be sent, instead that
581 * ICMP_PORT_UNREACH is sent here no matter it is TCP/UDP. --WZ
583 #ifdef CONFIG_IP_VS_IPV6
584 if (svc->af == AF_INET6) {
586 struct net *net = dev_net(skb_dst(skb)->dev);
588 skb->dev = net->loopback_dev;
590 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
593 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
600 static int sysctl_snat_reroute(struct sk_buff *skb)
602 struct netns_ipvs *ipvs = net_ipvs(skb_net(skb));
603 return ipvs->sysctl_snat_reroute;
606 static int sysctl_nat_icmp_send(struct net *net)
608 struct netns_ipvs *ipvs = net_ipvs(net);
609 return ipvs->sysctl_nat_icmp_send;
612 static int sysctl_expire_nodest_conn(struct netns_ipvs *ipvs)
614 return ipvs->sysctl_expire_nodest_conn;
619 static int sysctl_snat_reroute(struct sk_buff *skb) { return 0; }
620 static int sysctl_nat_icmp_send(struct net *net) { return 0; }
621 static int sysctl_expire_nodest_conn(struct netns_ipvs *ipvs) { return 0; }
625 __sum16 ip_vs_checksum_complete(struct sk_buff *skb, int offset)
627 return csum_fold(skb_checksum(skb, offset, skb->len - offset, 0));
630 static inline enum ip_defrag_users ip_vs_defrag_user(unsigned int hooknum)
632 if (NF_INET_LOCAL_IN == hooknum)
633 return IP_DEFRAG_VS_IN;
634 if (NF_INET_FORWARD == hooknum)
635 return IP_DEFRAG_VS_FWD;
636 return IP_DEFRAG_VS_OUT;
639 static inline int ip_vs_gather_frags(struct sk_buff *skb, u_int32_t user)
641 int err = ip_defrag(skb, user);
644 ip_send_check(ip_hdr(skb));
649 static int ip_vs_route_me_harder(int af, struct sk_buff *skb)
651 #ifdef CONFIG_IP_VS_IPV6
652 if (af == AF_INET6) {
653 if (sysctl_snat_reroute(skb) && ip6_route_me_harder(skb) != 0)
657 if ((sysctl_snat_reroute(skb) ||
658 skb_rtable(skb)->rt_flags & RTCF_LOCAL) &&
659 ip_route_me_harder(skb, RTN_LOCAL) != 0)
666 * Packet has been made sufficiently writable in caller
667 * - inout: 1=in->out, 0=out->in
669 void ip_vs_nat_icmp(struct sk_buff *skb, struct ip_vs_protocol *pp,
670 struct ip_vs_conn *cp, int inout)
672 struct iphdr *iph = ip_hdr(skb);
673 unsigned int icmp_offset = iph->ihl*4;
674 struct icmphdr *icmph = (struct icmphdr *)(skb_network_header(skb) +
676 struct iphdr *ciph = (struct iphdr *)(icmph + 1);
679 iph->saddr = cp->vaddr.ip;
681 ciph->daddr = cp->vaddr.ip;
684 iph->daddr = cp->daddr.ip;
686 ciph->saddr = cp->daddr.ip;
690 /* the TCP/UDP/SCTP port */
691 if (IPPROTO_TCP == ciph->protocol || IPPROTO_UDP == ciph->protocol ||
692 IPPROTO_SCTP == ciph->protocol) {
693 __be16 *ports = (void *)ciph + ciph->ihl*4;
696 ports[1] = cp->vport;
698 ports[0] = cp->dport;
701 /* And finally the ICMP checksum */
703 icmph->checksum = ip_vs_checksum_complete(skb, icmp_offset);
704 skb->ip_summed = CHECKSUM_UNNECESSARY;
707 IP_VS_DBG_PKT(11, AF_INET, pp, skb, (void *)ciph - (void *)iph,
708 "Forwarding altered outgoing ICMP");
710 IP_VS_DBG_PKT(11, AF_INET, pp, skb, (void *)ciph - (void *)iph,
711 "Forwarding altered incoming ICMP");
714 #ifdef CONFIG_IP_VS_IPV6
715 void ip_vs_nat_icmp_v6(struct sk_buff *skb, struct ip_vs_protocol *pp,
716 struct ip_vs_conn *cp, int inout)
718 struct ipv6hdr *iph = ipv6_hdr(skb);
719 unsigned int icmp_offset = 0;
720 unsigned int offs = 0; /* header offset*/
722 struct icmp6hdr *icmph;
723 struct ipv6hdr *ciph;
724 unsigned short fragoffs;
726 ipv6_find_hdr(skb, &icmp_offset, IPPROTO_ICMPV6, &fragoffs, NULL);
727 icmph = (struct icmp6hdr *)(skb_network_header(skb) + icmp_offset);
728 offs = icmp_offset + sizeof(struct icmp6hdr);
729 ciph = (struct ipv6hdr *)(skb_network_header(skb) + offs);
731 protocol = ipv6_find_hdr(skb, &offs, -1, &fragoffs, NULL);
734 iph->saddr = cp->vaddr.in6;
735 ciph->daddr = cp->vaddr.in6;
737 iph->daddr = cp->daddr.in6;
738 ciph->saddr = cp->daddr.in6;
741 /* the TCP/UDP/SCTP port */
742 if (!fragoffs && (IPPROTO_TCP == protocol || IPPROTO_UDP == protocol ||
743 IPPROTO_SCTP == protocol)) {
744 __be16 *ports = (void *)(skb_network_header(skb) + offs);
746 IP_VS_DBG(11, "%s() changed port %d to %d\n", __func__,
747 ntohs(inout ? ports[1] : ports[0]),
748 ntohs(inout ? cp->vport : cp->dport));
750 ports[1] = cp->vport;
752 ports[0] = cp->dport;
755 /* And finally the ICMP checksum */
756 icmph->icmp6_cksum = ~csum_ipv6_magic(&iph->saddr, &iph->daddr,
757 skb->len - icmp_offset,
759 skb->csum_start = skb_network_header(skb) - skb->head + icmp_offset;
760 skb->csum_offset = offsetof(struct icmp6hdr, icmp6_cksum);
761 skb->ip_summed = CHECKSUM_PARTIAL;
764 IP_VS_DBG_PKT(11, AF_INET6, pp, skb,
765 (void *)ciph - (void *)iph,
766 "Forwarding altered outgoing ICMPv6");
768 IP_VS_DBG_PKT(11, AF_INET6, pp, skb,
769 (void *)ciph - (void *)iph,
770 "Forwarding altered incoming ICMPv6");
774 /* Handle relevant response ICMP messages - forward to the right
777 static int handle_response_icmp(int af, struct sk_buff *skb,
778 union nf_inet_addr *snet,
779 __u8 protocol, struct ip_vs_conn *cp,
780 struct ip_vs_protocol *pp,
781 unsigned int offset, unsigned int ihl)
783 unsigned int verdict = NF_DROP;
785 if (IP_VS_FWD_METHOD(cp) != 0) {
786 pr_err("shouldn't reach here, because the box is on the "
787 "half connection in the tun/dr module.\n");
790 /* Ensure the checksum is correct */
791 if (!skb_csum_unnecessary(skb) && ip_vs_checksum_complete(skb, ihl)) {
792 /* Failed checksum! */
793 IP_VS_DBG_BUF(1, "Forward ICMP: failed checksum from %s!\n",
794 IP_VS_DBG_ADDR(af, snet));
798 if (IPPROTO_TCP == protocol || IPPROTO_UDP == protocol ||
799 IPPROTO_SCTP == protocol)
800 offset += 2 * sizeof(__u16);
801 if (!skb_make_writable(skb, offset))
804 #ifdef CONFIG_IP_VS_IPV6
806 ip_vs_nat_icmp_v6(skb, pp, cp, 1);
809 ip_vs_nat_icmp(skb, pp, cp, 1);
811 if (ip_vs_route_me_harder(af, skb))
814 /* do the statistics and put it back */
815 ip_vs_out_stats(cp, skb);
817 skb->ipvs_property = 1;
818 if (!(cp->flags & IP_VS_CONN_F_NFCT))
821 ip_vs_update_conntrack(skb, cp, 0);
825 __ip_vs_conn_put(cp);
831 * Handle ICMP messages in the inside-to-outside direction (outgoing).
832 * Find any that might be relevant, check against existing connections.
833 * Currently handles error types - unreachable, quench, ttl exceeded.
835 static int ip_vs_out_icmp(struct sk_buff *skb, int *related,
836 unsigned int hooknum)
839 struct icmphdr _icmph, *ic;
840 struct iphdr _ciph, *cih; /* The ip header contained within the ICMP */
841 struct ip_vs_iphdr ciph;
842 struct ip_vs_conn *cp;
843 struct ip_vs_protocol *pp;
844 unsigned int offset, ihl;
845 union nf_inet_addr snet;
849 /* reassemble IP fragments */
850 if (ip_is_fragment(ip_hdr(skb))) {
851 if (ip_vs_gather_frags(skb, ip_vs_defrag_user(hooknum)))
856 offset = ihl = iph->ihl * 4;
857 ic = skb_header_pointer(skb, offset, sizeof(_icmph), &_icmph);
861 IP_VS_DBG(12, "Outgoing ICMP (%d,%d) %pI4->%pI4\n",
862 ic->type, ntohs(icmp_id(ic)),
863 &iph->saddr, &iph->daddr);
866 * Work through seeing if this is for us.
867 * These checks are supposed to be in an order that means easy
868 * things are checked first to speed up processing.... however
869 * this means that some packets will manage to get a long way
870 * down this stack and then be rejected, but that's life.
872 if ((ic->type != ICMP_DEST_UNREACH) &&
873 (ic->type != ICMP_SOURCE_QUENCH) &&
874 (ic->type != ICMP_TIME_EXCEEDED)) {
879 /* Now find the contained IP header */
880 offset += sizeof(_icmph);
881 cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
883 return NF_ACCEPT; /* The packet looks wrong, ignore */
885 pp = ip_vs_proto_get(cih->protocol);
889 /* Is the embedded protocol header present? */
890 if (unlikely(cih->frag_off & htons(IP_OFFSET) &&
894 IP_VS_DBG_PKT(11, AF_INET, pp, skb, offset,
895 "Checking outgoing ICMP for");
897 ip_vs_fill_ip4hdr(cih, &ciph);
899 /* The embedded headers contain source and dest in reverse order */
900 cp = pp->conn_out_get(AF_INET, skb, &ciph, 1);
904 snet.ip = iph->saddr;
905 return handle_response_icmp(AF_INET, skb, &snet, cih->protocol, cp,
909 #ifdef CONFIG_IP_VS_IPV6
910 static int ip_vs_out_icmp_v6(struct sk_buff *skb, int *related,
911 unsigned int hooknum, struct ip_vs_iphdr *ipvsh)
913 struct icmp6hdr _icmph, *ic;
914 struct ipv6hdr _ip6h, *ip6h; /* The ip header contained within ICMP */
915 struct ip_vs_iphdr ciph = {.flags = 0, .fragoffs = 0};/*Contained IP */
916 struct ip_vs_conn *cp;
917 struct ip_vs_protocol *pp;
918 union nf_inet_addr snet;
919 unsigned int writable;
922 ic = frag_safe_skb_hp(skb, ipvsh->len, sizeof(_icmph), &_icmph, ipvsh);
927 * Work through seeing if this is for us.
928 * These checks are supposed to be in an order that means easy
929 * things are checked first to speed up processing.... however
930 * this means that some packets will manage to get a long way
931 * down this stack and then be rejected, but that's life.
933 if (ic->icmp6_type & ICMPV6_INFOMSG_MASK) {
937 /* Fragment header that is before ICMP header tells us that:
938 * it's not an error message since they can't be fragmented.
940 if (ipvsh->flags & IP6_FH_F_FRAG)
943 IP_VS_DBG(8, "Outgoing ICMPv6 (%d,%d) %pI6c->%pI6c\n",
944 ic->icmp6_type, ntohs(icmpv6_id(ic)),
945 &ipvsh->saddr, &ipvsh->daddr);
947 /* Now find the contained IP header */
948 ciph.len = ipvsh->len + sizeof(_icmph);
949 ip6h = skb_header_pointer(skb, ciph.len, sizeof(_ip6h), &_ip6h);
951 return NF_ACCEPT; /* The packet looks wrong, ignore */
952 ciph.saddr.in6 = ip6h->saddr; /* conn_out_get() handles reverse order */
953 ciph.daddr.in6 = ip6h->daddr;
954 /* skip possible IPv6 exthdrs of contained IPv6 packet */
955 ciph.protocol = ipv6_find_hdr(skb, &ciph.len, -1, &ciph.fragoffs, NULL);
956 if (ciph.protocol < 0)
957 return NF_ACCEPT; /* Contained IPv6 hdr looks wrong, ignore */
959 pp = ip_vs_proto_get(ciph.protocol);
963 /* The embedded headers contain source and dest in reverse order */
964 cp = pp->conn_out_get(AF_INET6, skb, &ciph, 1);
968 snet.in6 = ciph.saddr.in6;
970 return handle_response_icmp(AF_INET6, skb, &snet, ciph.protocol, cp,
971 pp, writable, sizeof(struct ipv6hdr));
976 * Check if sctp chunc is ABORT chunk
978 static inline int is_sctp_abort(const struct sk_buff *skb, int nh_len)
980 sctp_chunkhdr_t *sch, schunk;
981 sch = skb_header_pointer(skb, nh_len + sizeof(sctp_sctphdr_t),
982 sizeof(schunk), &schunk);
985 if (sch->type == SCTP_CID_ABORT)
990 static inline int is_tcp_reset(const struct sk_buff *skb, int nh_len)
992 struct tcphdr _tcph, *th;
994 th = skb_header_pointer(skb, nh_len, sizeof(_tcph), &_tcph);
1000 /* Handle response packets: rewrite addresses and send away...
1003 handle_response(int af, struct sk_buff *skb, struct ip_vs_proto_data *pd,
1004 struct ip_vs_conn *cp, struct ip_vs_iphdr *iph)
1006 struct ip_vs_protocol *pp = pd->pp;
1008 IP_VS_DBG_PKT(11, af, pp, skb, 0, "Outgoing packet");
1010 if (!skb_make_writable(skb, iph->len))
1013 /* mangle the packet */
1014 if (pp->snat_handler && !pp->snat_handler(skb, pp, cp, iph))
1017 #ifdef CONFIG_IP_VS_IPV6
1019 ipv6_hdr(skb)->saddr = cp->vaddr.in6;
1023 ip_hdr(skb)->saddr = cp->vaddr.ip;
1024 ip_send_check(ip_hdr(skb));
1028 * nf_iterate does not expect change in the skb->dst->dev.
1029 * It looks like it is not fatal to enable this code for hooks
1030 * where our handlers are at the end of the chain list and
1031 * when all next handlers use skb->dst->dev and not outdev.
1032 * It will definitely route properly the inout NAT traffic
1033 * when multiple paths are used.
1036 /* For policy routing, packets originating from this
1037 * machine itself may be routed differently to packets
1038 * passing through. We want this packet to be routed as
1039 * if it came from this machine itself. So re-compute
1040 * the routing information.
1042 if (ip_vs_route_me_harder(af, skb))
1045 IP_VS_DBG_PKT(10, af, pp, skb, 0, "After SNAT");
1047 ip_vs_out_stats(cp, skb);
1048 ip_vs_set_state(cp, IP_VS_DIR_OUTPUT, skb, pd);
1049 skb->ipvs_property = 1;
1050 if (!(cp->flags & IP_VS_CONN_F_NFCT))
1053 ip_vs_update_conntrack(skb, cp, 0);
1067 * Check if outgoing packet belongs to the established ip_vs_conn.
1070 ip_vs_out(unsigned int hooknum, struct sk_buff *skb, int af)
1072 struct net *net = NULL;
1073 struct ip_vs_iphdr iph;
1074 struct ip_vs_protocol *pp;
1075 struct ip_vs_proto_data *pd;
1076 struct ip_vs_conn *cp;
1080 /* Already marked as IPVS request or reply? */
1081 if (skb->ipvs_property)
1084 /* Bad... Do not break raw sockets */
1085 if (unlikely(skb->sk != NULL && hooknum == NF_INET_LOCAL_OUT &&
1087 struct sock *sk = skb->sk;
1088 struct inet_sock *inet = inet_sk(skb->sk);
1090 if (inet && sk->sk_family == PF_INET && inet->nodefrag)
1094 if (unlikely(!skb_dst(skb)))
1098 if (!net_ipvs(net)->enable)
1101 ip_vs_fill_iph_skb(af, skb, &iph);
1102 #ifdef CONFIG_IP_VS_IPV6
1103 if (af == AF_INET6) {
1104 if (!iph.fragoffs && skb_nfct_reasm(skb)) {
1105 struct sk_buff *reasm = skb_nfct_reasm(skb);
1106 /* Save fw mark for coming frags */
1107 reasm->ipvs_property = 1;
1108 reasm->mark = skb->mark;
1110 if (unlikely(iph.protocol == IPPROTO_ICMPV6)) {
1112 int verdict = ip_vs_out_icmp_v6(skb, &related,
1120 if (unlikely(iph.protocol == IPPROTO_ICMP)) {
1122 int verdict = ip_vs_out_icmp(skb, &related, hooknum);
1128 pd = ip_vs_proto_data_get(net, iph.protocol);
1133 /* reassemble IP fragments */
1134 #ifdef CONFIG_IP_VS_IPV6
1137 if (unlikely(ip_is_fragment(ip_hdr(skb)) && !pp->dont_defrag)) {
1138 if (ip_vs_gather_frags(skb,
1139 ip_vs_defrag_user(hooknum)))
1142 ip_vs_fill_ip4hdr(skb_network_header(skb), &iph);
1146 * Check if the packet belongs to an existing entry
1148 cp = pp->conn_out_get(af, skb, &iph, 0);
1151 return handle_response(af, skb, pd, cp, &iph);
1152 if (sysctl_nat_icmp_send(net) &&
1153 (pp->protocol == IPPROTO_TCP ||
1154 pp->protocol == IPPROTO_UDP ||
1155 pp->protocol == IPPROTO_SCTP)) {
1156 __be16 _ports[2], *pptr;
1158 pptr = frag_safe_skb_hp(skb, iph.len,
1159 sizeof(_ports), _ports, &iph);
1161 return NF_ACCEPT; /* Not for me */
1162 if (ip_vs_has_real_service(net, af, iph.protocol, &iph.saddr,
1165 * Notify the real server: there is no
1166 * existing entry if it is not RST
1167 * packet or not TCP packet.
1169 if ((iph.protocol != IPPROTO_TCP &&
1170 iph.protocol != IPPROTO_SCTP)
1171 || ((iph.protocol == IPPROTO_TCP
1172 && !is_tcp_reset(skb, iph.len))
1173 || (iph.protocol == IPPROTO_SCTP
1174 && !is_sctp_abort(skb,
1176 #ifdef CONFIG_IP_VS_IPV6
1177 if (af == AF_INET6) {
1179 skb->dev = net->loopback_dev;
1181 ICMPV6_DEST_UNREACH,
1182 ICMPV6_PORT_UNREACH,
1188 ICMP_PORT_UNREACH, 0);
1193 IP_VS_DBG_PKT(12, af, pp, skb, 0,
1194 "ip_vs_out: packet continues traversal as normal");
1199 * It is hooked at the NF_INET_FORWARD and NF_INET_LOCAL_IN chain,
1200 * used only for VS/NAT.
1201 * Check if packet is reply for established ip_vs_conn.
1204 ip_vs_reply4(unsigned int hooknum, struct sk_buff *skb,
1205 const struct net_device *in, const struct net_device *out,
1206 int (*okfn)(struct sk_buff *))
1208 return ip_vs_out(hooknum, skb, AF_INET);
1212 * It is hooked at the NF_INET_LOCAL_OUT chain, used only for VS/NAT.
1213 * Check if packet is reply for established ip_vs_conn.
1216 ip_vs_local_reply4(unsigned int hooknum, struct sk_buff *skb,
1217 const struct net_device *in, const struct net_device *out,
1218 int (*okfn)(struct sk_buff *))
1220 unsigned int verdict;
1222 /* Disable BH in LOCAL_OUT until all places are fixed */
1224 verdict = ip_vs_out(hooknum, skb, AF_INET);
1229 #ifdef CONFIG_IP_VS_IPV6
1232 * It is hooked at the NF_INET_FORWARD and NF_INET_LOCAL_IN chain,
1233 * used only for VS/NAT.
1234 * Check if packet is reply for established ip_vs_conn.
1237 ip_vs_reply6(unsigned int hooknum, struct sk_buff *skb,
1238 const struct net_device *in, const struct net_device *out,
1239 int (*okfn)(struct sk_buff *))
1241 return ip_vs_out(hooknum, skb, AF_INET6);
1245 * It is hooked at the NF_INET_LOCAL_OUT chain, used only for VS/NAT.
1246 * Check if packet is reply for established ip_vs_conn.
1249 ip_vs_local_reply6(unsigned int hooknum, struct sk_buff *skb,
1250 const struct net_device *in, const struct net_device *out,
1251 int (*okfn)(struct sk_buff *))
1253 unsigned int verdict;
1255 /* Disable BH in LOCAL_OUT until all places are fixed */
1257 verdict = ip_vs_out(hooknum, skb, AF_INET6);
1265 * Handle ICMP messages in the outside-to-inside direction (incoming).
1266 * Find any that might be relevant, check against existing connections,
1267 * forward to the right destination host if relevant.
1268 * Currently handles error types - unreachable, quench, ttl exceeded.
1271 ip_vs_in_icmp(struct sk_buff *skb, int *related, unsigned int hooknum)
1273 struct net *net = NULL;
1275 struct icmphdr _icmph, *ic;
1276 struct iphdr _ciph, *cih; /* The ip header contained within the ICMP */
1277 struct ip_vs_iphdr ciph;
1278 struct ip_vs_conn *cp;
1279 struct ip_vs_protocol *pp;
1280 struct ip_vs_proto_data *pd;
1281 unsigned int offset, offset2, ihl, verdict;
1286 /* reassemble IP fragments */
1287 if (ip_is_fragment(ip_hdr(skb))) {
1288 if (ip_vs_gather_frags(skb, ip_vs_defrag_user(hooknum)))
1293 offset = ihl = iph->ihl * 4;
1294 ic = skb_header_pointer(skb, offset, sizeof(_icmph), &_icmph);
1298 IP_VS_DBG(12, "Incoming ICMP (%d,%d) %pI4->%pI4\n",
1299 ic->type, ntohs(icmp_id(ic)),
1300 &iph->saddr, &iph->daddr);
1303 * Work through seeing if this is for us.
1304 * These checks are supposed to be in an order that means easy
1305 * things are checked first to speed up processing.... however
1306 * this means that some packets will manage to get a long way
1307 * down this stack and then be rejected, but that's life.
1309 if ((ic->type != ICMP_DEST_UNREACH) &&
1310 (ic->type != ICMP_SOURCE_QUENCH) &&
1311 (ic->type != ICMP_TIME_EXCEEDED)) {
1316 /* Now find the contained IP header */
1317 offset += sizeof(_icmph);
1318 cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
1320 return NF_ACCEPT; /* The packet looks wrong, ignore */
1324 /* Special case for errors for IPIP packets */
1326 if (cih->protocol == IPPROTO_IPIP) {
1327 if (unlikely(cih->frag_off & htons(IP_OFFSET)))
1329 /* Error for our IPIP must arrive at LOCAL_IN */
1330 if (!(skb_rtable(skb)->rt_flags & RTCF_LOCAL))
1332 offset += cih->ihl * 4;
1333 cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
1335 return NF_ACCEPT; /* The packet looks wrong, ignore */
1339 pd = ip_vs_proto_data_get(net, cih->protocol);
1344 /* Is the embedded protocol header present? */
1345 if (unlikely(cih->frag_off & htons(IP_OFFSET) &&
1349 IP_VS_DBG_PKT(11, AF_INET, pp, skb, offset,
1350 "Checking incoming ICMP for");
1353 ip_vs_fill_ip4hdr(cih, &ciph);
1356 /* The embedded headers contain source and dest in reverse order.
1357 * For IPIP this is error for request, not for reply.
1359 cp = pp->conn_in_get(AF_INET, skb, &ciph, ipip ? 0 : 1);
1365 /* Ensure the checksum is correct */
1366 if (!skb_csum_unnecessary(skb) && ip_vs_checksum_complete(skb, ihl)) {
1367 /* Failed checksum! */
1368 IP_VS_DBG(1, "Incoming ICMP: failed checksum from %pI4!\n",
1374 __be32 info = ic->un.gateway;
1376 /* Update the MTU */
1377 if (ic->type == ICMP_DEST_UNREACH &&
1378 ic->code == ICMP_FRAG_NEEDED) {
1379 struct ip_vs_dest *dest = cp->dest;
1380 u32 mtu = ntohs(ic->un.frag.mtu);
1382 /* Strip outer IP and ICMP, go to IPIP header */
1383 __skb_pull(skb, ihl + sizeof(_icmph));
1384 offset2 -= ihl + sizeof(_icmph);
1385 skb_reset_network_header(skb);
1386 IP_VS_DBG(12, "ICMP for IPIP %pI4->%pI4: mtu=%u\n",
1387 &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr, mtu);
1388 ipv4_update_pmtu(skb, dev_net(skb->dev),
1390 /* Client uses PMTUD? */
1391 if (!(cih->frag_off & htons(IP_DF)))
1393 /* Prefer the resulting PMTU */
1395 struct ip_vs_dest_dst *dest_dst;
1398 dest_dst = rcu_dereference(dest->dest_dst);
1400 mtu = dst_mtu(dest_dst->dst_cache);
1403 if (mtu > 68 + sizeof(struct iphdr))
1404 mtu -= sizeof(struct iphdr);
1407 /* Strip outer IP, ICMP and IPIP, go to IP header of
1410 __skb_pull(skb, offset2);
1411 skb_reset_network_header(skb);
1412 IP_VS_DBG(12, "Sending ICMP for %pI4->%pI4: t=%u, c=%u, i=%u\n",
1413 &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr,
1414 ic->type, ic->code, ntohl(info));
1415 icmp_send(skb, ic->type, ic->code, info);
1416 /* ICMP can be shorter but anyways, account it */
1417 ip_vs_out_stats(cp, skb);
1421 verdict = NF_STOLEN;
1425 /* do the statistics and put it back */
1426 ip_vs_in_stats(cp, skb);
1427 if (IPPROTO_TCP == cih->protocol || IPPROTO_UDP == cih->protocol)
1428 offset += 2 * sizeof(__u16);
1429 verdict = ip_vs_icmp_xmit(skb, cp, pp, offset, hooknum, &ciph);
1432 __ip_vs_conn_put(cp);
1437 #ifdef CONFIG_IP_VS_IPV6
1438 static int ip_vs_in_icmp_v6(struct sk_buff *skb, int *related,
1439 unsigned int hooknum, struct ip_vs_iphdr *iph)
1441 struct net *net = NULL;
1442 struct ipv6hdr _ip6h, *ip6h;
1443 struct icmp6hdr _icmph, *ic;
1444 struct ip_vs_iphdr ciph = {.flags = 0, .fragoffs = 0};/*Contained IP */
1445 struct ip_vs_conn *cp;
1446 struct ip_vs_protocol *pp;
1447 struct ip_vs_proto_data *pd;
1448 unsigned int offs_ciph, writable, verdict;
1452 ic = frag_safe_skb_hp(skb, iph->len, sizeof(_icmph), &_icmph, iph);
1457 * Work through seeing if this is for us.
1458 * These checks are supposed to be in an order that means easy
1459 * things are checked first to speed up processing.... however
1460 * this means that some packets will manage to get a long way
1461 * down this stack and then be rejected, but that's life.
1463 if (ic->icmp6_type & ICMPV6_INFOMSG_MASK) {
1467 /* Fragment header that is before ICMP header tells us that:
1468 * it's not an error message since they can't be fragmented.
1470 if (iph->flags & IP6_FH_F_FRAG)
1473 IP_VS_DBG(8, "Incoming ICMPv6 (%d,%d) %pI6c->%pI6c\n",
1474 ic->icmp6_type, ntohs(icmpv6_id(ic)),
1475 &iph->saddr, &iph->daddr);
1477 /* Now find the contained IP header */
1478 ciph.len = iph->len + sizeof(_icmph);
1479 offs_ciph = ciph.len; /* Save ip header offset */
1480 ip6h = skb_header_pointer(skb, ciph.len, sizeof(_ip6h), &_ip6h);
1482 return NF_ACCEPT; /* The packet looks wrong, ignore */
1483 ciph.saddr.in6 = ip6h->saddr; /* conn_in_get() handles reverse order */
1484 ciph.daddr.in6 = ip6h->daddr;
1485 /* skip possible IPv6 exthdrs of contained IPv6 packet */
1486 ciph.protocol = ipv6_find_hdr(skb, &ciph.len, -1, &ciph.fragoffs, NULL);
1487 if (ciph.protocol < 0)
1488 return NF_ACCEPT; /* Contained IPv6 hdr looks wrong, ignore */
1491 pd = ip_vs_proto_data_get(net, ciph.protocol);
1496 /* Cannot handle fragmented embedded protocol */
1500 IP_VS_DBG_PKT(11, AF_INET6, pp, skb, offs_ciph,
1501 "Checking incoming ICMPv6 for");
1503 /* The embedded headers contain source and dest in reverse order
1504 * if not from localhost
1506 cp = pp->conn_in_get(AF_INET6, skb, &ciph,
1507 (hooknum == NF_INET_LOCAL_OUT) ? 0 : 1);
1511 /* VS/TUN, VS/DR and LOCALNODE just let it go */
1512 if ((hooknum == NF_INET_LOCAL_OUT) &&
1513 (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ)) {
1514 __ip_vs_conn_put(cp);
1518 /* do the statistics and put it back */
1519 ip_vs_in_stats(cp, skb);
1521 /* Need to mangle contained IPv6 header in ICMPv6 packet */
1522 writable = ciph.len;
1523 if (IPPROTO_TCP == ciph.protocol || IPPROTO_UDP == ciph.protocol ||
1524 IPPROTO_SCTP == ciph.protocol)
1525 writable += 2 * sizeof(__u16); /* Also mangle ports */
1527 verdict = ip_vs_icmp_xmit_v6(skb, cp, pp, writable, hooknum, &ciph);
1529 __ip_vs_conn_put(cp);
1537 * Check if it's for virtual services, look it up,
1538 * and send it on its way...
1541 ip_vs_in(unsigned int hooknum, struct sk_buff *skb, int af)
1544 struct ip_vs_iphdr iph;
1545 struct ip_vs_protocol *pp;
1546 struct ip_vs_proto_data *pd;
1547 struct ip_vs_conn *cp;
1549 struct netns_ipvs *ipvs;
1551 /* Already marked as IPVS request or reply? */
1552 if (skb->ipvs_property)
1557 * - remote client: only PACKET_HOST
1558 * - route: used for struct net when skb->dev is unset
1560 if (unlikely((skb->pkt_type != PACKET_HOST &&
1561 hooknum != NF_INET_LOCAL_OUT) ||
1563 ip_vs_fill_iph_skb(af, skb, &iph);
1564 IP_VS_DBG_BUF(12, "packet type=%d proto=%d daddr=%s"
1565 " ignored in hook %u\n",
1566 skb->pkt_type, iph.protocol,
1567 IP_VS_DBG_ADDR(af, &iph.daddr), hooknum);
1570 /* ipvs enabled in this netns ? */
1572 ipvs = net_ipvs(net);
1573 if (unlikely(sysctl_backup_only(ipvs) || !ipvs->enable))
1576 ip_vs_fill_iph_skb(af, skb, &iph);
1578 /* Bad... Do not break raw sockets */
1579 if (unlikely(skb->sk != NULL && hooknum == NF_INET_LOCAL_OUT &&
1581 struct sock *sk = skb->sk;
1582 struct inet_sock *inet = inet_sk(skb->sk);
1584 if (inet && sk->sk_family == PF_INET && inet->nodefrag)
1588 #ifdef CONFIG_IP_VS_IPV6
1589 if (af == AF_INET6) {
1590 if (!iph.fragoffs && skb_nfct_reasm(skb)) {
1591 struct sk_buff *reasm = skb_nfct_reasm(skb);
1592 /* Save fw mark for coming frags. */
1593 reasm->ipvs_property = 1;
1594 reasm->mark = skb->mark;
1596 if (unlikely(iph.protocol == IPPROTO_ICMPV6)) {
1598 int verdict = ip_vs_in_icmp_v6(skb, &related, hooknum,
1606 if (unlikely(iph.protocol == IPPROTO_ICMP)) {
1608 int verdict = ip_vs_in_icmp(skb, &related, hooknum);
1614 /* Protocol supported? */
1615 pd = ip_vs_proto_data_get(net, iph.protocol);
1620 * Check if the packet belongs to an existing connection entry
1622 cp = pp->conn_in_get(af, skb, &iph, 0);
1623 if (unlikely(!cp) && !iph.fragoffs) {
1624 /* No (second) fragments need to enter here, as nf_defrag_ipv6
1625 * replayed fragment zero will already have created the cp
1629 /* Schedule and create new connection entry into &cp */
1630 if (!pp->conn_schedule(af, skb, pd, &v, &cp, &iph))
1634 if (unlikely(!cp)) {
1635 /* sorry, all this trouble for a no-hit :) */
1636 IP_VS_DBG_PKT(12, af, pp, skb, 0,
1637 "ip_vs_in: packet continues traversal as normal");
1638 if (iph.fragoffs && !skb_nfct_reasm(skb)) {
1639 /* Fragment that couldn't be mapped to a conn entry
1640 * and don't have any pointer to a reasm skb
1641 * is missing module nf_defrag_ipv6
1643 IP_VS_DBG_RL("Unhandled frag, load nf_defrag_ipv6\n");
1644 IP_VS_DBG_PKT(7, af, pp, skb, 0, "unhandled fragment");
1649 IP_VS_DBG_PKT(11, af, pp, skb, 0, "Incoming packet");
1650 /* Check the server status */
1651 if (cp->dest && !(cp->dest->flags & IP_VS_DEST_F_AVAILABLE)) {
1652 /* the destination server is not available */
1654 if (sysctl_expire_nodest_conn(ipvs)) {
1655 /* try to expire the connection immediately */
1656 ip_vs_conn_expire_now(cp);
1658 /* don't restart its timer, and silently
1660 __ip_vs_conn_put(cp);
1664 ip_vs_in_stats(cp, skb);
1665 ip_vs_set_state(cp, IP_VS_DIR_INPUT, skb, pd);
1666 if (cp->packet_xmit)
1667 ret = cp->packet_xmit(skb, cp, pp, &iph);
1668 /* do not touch skb anymore */
1670 IP_VS_DBG_RL("warning: packet_xmit is null");
1674 /* Increase its packet counter and check if it is needed
1675 * to be synchronized
1677 * Sync connection if it is about to close to
1678 * encorage the standby servers to update the connections timeout
1680 * For ONE_PKT let ip_vs_sync_conn() do the filter work.
1683 if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
1684 pkts = sysctl_sync_threshold(ipvs);
1686 pkts = atomic_add_return(1, &cp->in_pkts);
1688 if (ipvs->sync_state & IP_VS_STATE_MASTER)
1689 ip_vs_sync_conn(net, cp, pkts);
1696 * AF_INET handler in NF_INET_LOCAL_IN chain
1697 * Schedule and forward packets from remote clients
1700 ip_vs_remote_request4(unsigned int hooknum, struct sk_buff *skb,
1701 const struct net_device *in,
1702 const struct net_device *out,
1703 int (*okfn)(struct sk_buff *))
1705 return ip_vs_in(hooknum, skb, AF_INET);
1709 * AF_INET handler in NF_INET_LOCAL_OUT chain
1710 * Schedule and forward packets from local clients
1713 ip_vs_local_request4(unsigned int hooknum, struct sk_buff *skb,
1714 const struct net_device *in, const struct net_device *out,
1715 int (*okfn)(struct sk_buff *))
1717 unsigned int verdict;
1719 /* Disable BH in LOCAL_OUT until all places are fixed */
1721 verdict = ip_vs_in(hooknum, skb, AF_INET);
1726 #ifdef CONFIG_IP_VS_IPV6
1729 * AF_INET6 fragment handling
1730 * Copy info from first fragment, to the rest of them.
1733 ip_vs_preroute_frag6(unsigned int hooknum, struct sk_buff *skb,
1734 const struct net_device *in,
1735 const struct net_device *out,
1736 int (*okfn)(struct sk_buff *))
1738 struct sk_buff *reasm = skb_nfct_reasm(skb);
1741 /* Skip if not a "replay" from nf_ct_frag6_output or first fragment.
1742 * ipvs_property is set when checking first fragment
1743 * in ip_vs_in() and ip_vs_out().
1746 IP_VS_DBG(2, "Fragment recv prop:%d\n", reasm->ipvs_property);
1747 if (!reasm || !reasm->ipvs_property)
1751 if (!net_ipvs(net)->enable)
1754 /* Copy stored fw mark, saved in ip_vs_{in,out} */
1755 skb->mark = reasm->mark;
1761 * AF_INET6 handler in NF_INET_LOCAL_IN chain
1762 * Schedule and forward packets from remote clients
1765 ip_vs_remote_request6(unsigned int hooknum, struct sk_buff *skb,
1766 const struct net_device *in,
1767 const struct net_device *out,
1768 int (*okfn)(struct sk_buff *))
1770 return ip_vs_in(hooknum, skb, AF_INET6);
1774 * AF_INET6 handler in NF_INET_LOCAL_OUT chain
1775 * Schedule and forward packets from local clients
1778 ip_vs_local_request6(unsigned int hooknum, struct sk_buff *skb,
1779 const struct net_device *in, const struct net_device *out,
1780 int (*okfn)(struct sk_buff *))
1782 unsigned int verdict;
1784 /* Disable BH in LOCAL_OUT until all places are fixed */
1786 verdict = ip_vs_in(hooknum, skb, AF_INET6);
1795 * It is hooked at the NF_INET_FORWARD chain, in order to catch ICMP
1796 * related packets destined for 0.0.0.0/0.
1797 * When fwmark-based virtual service is used, such as transparent
1798 * cache cluster, TCP packets can be marked and routed to ip_vs_in,
1799 * but ICMP destined for 0.0.0.0/0 cannot not be easily marked and
1800 * sent to ip_vs_in_icmp. So, catch them at the NF_INET_FORWARD chain
1801 * and send them to ip_vs_in_icmp.
1804 ip_vs_forward_icmp(unsigned int hooknum, struct sk_buff *skb,
1805 const struct net_device *in, const struct net_device *out,
1806 int (*okfn)(struct sk_buff *))
1810 struct netns_ipvs *ipvs;
1812 if (ip_hdr(skb)->protocol != IPPROTO_ICMP)
1815 /* ipvs enabled in this netns ? */
1817 ipvs = net_ipvs(net);
1818 if (unlikely(sysctl_backup_only(ipvs) || !ipvs->enable))
1821 return ip_vs_in_icmp(skb, &r, hooknum);
1824 #ifdef CONFIG_IP_VS_IPV6
1826 ip_vs_forward_icmp_v6(unsigned int hooknum, struct sk_buff *skb,
1827 const struct net_device *in, const struct net_device *out,
1828 int (*okfn)(struct sk_buff *))
1832 struct netns_ipvs *ipvs;
1833 struct ip_vs_iphdr iphdr;
1835 ip_vs_fill_iph_skb(AF_INET6, skb, &iphdr);
1836 if (iphdr.protocol != IPPROTO_ICMPV6)
1839 /* ipvs enabled in this netns ? */
1841 ipvs = net_ipvs(net);
1842 if (unlikely(sysctl_backup_only(ipvs) || !ipvs->enable))
1845 return ip_vs_in_icmp_v6(skb, &r, hooknum, &iphdr);
1850 static struct nf_hook_ops ip_vs_ops[] __read_mostly = {
1851 /* After packet filtering, change source only for VS/NAT */
1853 .hook = ip_vs_reply4,
1854 .owner = THIS_MODULE,
1856 .hooknum = NF_INET_LOCAL_IN,
1857 .priority = NF_IP_PRI_NAT_SRC - 2,
1859 /* After packet filtering, forward packet through VS/DR, VS/TUN,
1860 * or VS/NAT(change destination), so that filtering rules can be
1861 * applied to IPVS. */
1863 .hook = ip_vs_remote_request4,
1864 .owner = THIS_MODULE,
1866 .hooknum = NF_INET_LOCAL_IN,
1867 .priority = NF_IP_PRI_NAT_SRC - 1,
1869 /* Before ip_vs_in, change source only for VS/NAT */
1871 .hook = ip_vs_local_reply4,
1872 .owner = THIS_MODULE,
1874 .hooknum = NF_INET_LOCAL_OUT,
1875 .priority = NF_IP_PRI_NAT_DST + 1,
1877 /* After mangle, schedule and forward local requests */
1879 .hook = ip_vs_local_request4,
1880 .owner = THIS_MODULE,
1882 .hooknum = NF_INET_LOCAL_OUT,
1883 .priority = NF_IP_PRI_NAT_DST + 2,
1885 /* After packet filtering (but before ip_vs_out_icmp), catch icmp
1886 * destined for 0.0.0.0/0, which is for incoming IPVS connections */
1888 .hook = ip_vs_forward_icmp,
1889 .owner = THIS_MODULE,
1891 .hooknum = NF_INET_FORWARD,
1894 /* After packet filtering, change source only for VS/NAT */
1896 .hook = ip_vs_reply4,
1897 .owner = THIS_MODULE,
1899 .hooknum = NF_INET_FORWARD,
1902 #ifdef CONFIG_IP_VS_IPV6
1903 /* After mangle & nat fetch 2:nd fragment and following */
1905 .hook = ip_vs_preroute_frag6,
1906 .owner = THIS_MODULE,
1908 .hooknum = NF_INET_PRE_ROUTING,
1909 .priority = NF_IP6_PRI_NAT_DST + 1,
1911 /* After packet filtering, change source only for VS/NAT */
1913 .hook = ip_vs_reply6,
1914 .owner = THIS_MODULE,
1916 .hooknum = NF_INET_LOCAL_IN,
1917 .priority = NF_IP6_PRI_NAT_SRC - 2,
1919 /* After packet filtering, forward packet through VS/DR, VS/TUN,
1920 * or VS/NAT(change destination), so that filtering rules can be
1921 * applied to IPVS. */
1923 .hook = ip_vs_remote_request6,
1924 .owner = THIS_MODULE,
1926 .hooknum = NF_INET_LOCAL_IN,
1927 .priority = NF_IP6_PRI_NAT_SRC - 1,
1929 /* Before ip_vs_in, change source only for VS/NAT */
1931 .hook = ip_vs_local_reply6,
1932 .owner = THIS_MODULE,
1934 .hooknum = NF_INET_LOCAL_OUT,
1935 .priority = NF_IP6_PRI_NAT_DST + 1,
1937 /* After mangle, schedule and forward local requests */
1939 .hook = ip_vs_local_request6,
1940 .owner = THIS_MODULE,
1942 .hooknum = NF_INET_LOCAL_OUT,
1943 .priority = NF_IP6_PRI_NAT_DST + 2,
1945 /* After packet filtering (but before ip_vs_out_icmp), catch icmp
1946 * destined for 0.0.0.0/0, which is for incoming IPVS connections */
1948 .hook = ip_vs_forward_icmp_v6,
1949 .owner = THIS_MODULE,
1951 .hooknum = NF_INET_FORWARD,
1954 /* After packet filtering, change source only for VS/NAT */
1956 .hook = ip_vs_reply6,
1957 .owner = THIS_MODULE,
1959 .hooknum = NF_INET_FORWARD,
1965 * Initialize IP Virtual Server netns mem.
1967 static int __net_init __ip_vs_init(struct net *net)
1969 struct netns_ipvs *ipvs;
1971 ipvs = net_generic(net, ip_vs_net_id);
1975 /* Hold the beast until a service is registerd */
1978 /* Counters used for creating unique names */
1979 ipvs->gen = atomic_read(&ipvs_netns_cnt);
1980 atomic_inc(&ipvs_netns_cnt);
1983 if (ip_vs_estimator_net_init(net) < 0)
1984 goto estimator_fail;
1986 if (ip_vs_control_net_init(net) < 0)
1989 if (ip_vs_protocol_net_init(net) < 0)
1992 if (ip_vs_app_net_init(net) < 0)
1995 if (ip_vs_conn_net_init(net) < 0)
1998 if (ip_vs_sync_net_init(net) < 0)
2001 printk(KERN_INFO "IPVS: Creating netns size=%zu id=%d\n",
2002 sizeof(struct netns_ipvs), ipvs->gen);
2009 ip_vs_conn_net_cleanup(net);
2011 ip_vs_app_net_cleanup(net);
2013 ip_vs_protocol_net_cleanup(net);
2015 ip_vs_control_net_cleanup(net);
2017 ip_vs_estimator_net_cleanup(net);
2023 static void __net_exit __ip_vs_cleanup(struct net *net)
2025 ip_vs_service_net_cleanup(net); /* ip_vs_flush() with locks */
2026 ip_vs_conn_net_cleanup(net);
2027 ip_vs_app_net_cleanup(net);
2028 ip_vs_protocol_net_cleanup(net);
2029 ip_vs_control_net_cleanup(net);
2030 ip_vs_estimator_net_cleanup(net);
2031 IP_VS_DBG(2, "ipvs netns %d released\n", net_ipvs(net)->gen);
2035 static void __net_exit __ip_vs_dev_cleanup(struct net *net)
2038 net_ipvs(net)->enable = 0; /* Disable packet reception */
2040 ip_vs_sync_net_cleanup(net);
2044 static struct pernet_operations ipvs_core_ops = {
2045 .init = __ip_vs_init,
2046 .exit = __ip_vs_cleanup,
2047 .id = &ip_vs_net_id,
2048 .size = sizeof(struct netns_ipvs),
2051 static struct pernet_operations ipvs_core_dev_ops = {
2052 .exit = __ip_vs_dev_cleanup,
2056 * Initialize IP Virtual Server
2058 static int __init ip_vs_init(void)
2062 ret = ip_vs_control_init();
2064 pr_err("can't setup control.\n");
2068 ip_vs_protocol_init();
2070 ret = ip_vs_conn_init();
2072 pr_err("can't setup connection table.\n");
2073 goto cleanup_protocol;
2076 ret = register_pernet_subsys(&ipvs_core_ops); /* Alloc ip_vs struct */
2080 ret = register_pernet_device(&ipvs_core_dev_ops);
2084 ret = nf_register_hooks(ip_vs_ops, ARRAY_SIZE(ip_vs_ops));
2086 pr_err("can't register hooks.\n");
2090 ret = ip_vs_register_nl_ioctl();
2092 pr_err("can't register netlink/ioctl.\n");
2096 pr_info("ipvs loaded.\n");
2101 nf_unregister_hooks(ip_vs_ops, ARRAY_SIZE(ip_vs_ops));
2103 unregister_pernet_device(&ipvs_core_dev_ops);
2105 unregister_pernet_subsys(&ipvs_core_ops);
2107 ip_vs_conn_cleanup();
2109 ip_vs_protocol_cleanup();
2110 ip_vs_control_cleanup();
2115 static void __exit ip_vs_cleanup(void)
2117 ip_vs_unregister_nl_ioctl();
2118 nf_unregister_hooks(ip_vs_ops, ARRAY_SIZE(ip_vs_ops));
2119 unregister_pernet_device(&ipvs_core_dev_ops);
2120 unregister_pernet_subsys(&ipvs_core_ops); /* free ip_vs struct */
2121 ip_vs_conn_cleanup();
2122 ip_vs_protocol_cleanup();
2123 ip_vs_control_cleanup();
2124 pr_info("ipvs unloaded.\n");
2127 module_init(ip_vs_init);
2128 module_exit(ip_vs_cleanup);
2129 MODULE_LICENSE("GPL");