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 int 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 (likely(pd->pp->state_transition))
197 pd->pp->state_transition(cp, direction, skb, pd);
201 ip_vs_conn_fill_param_persist(const struct ip_vs_service *svc,
202 struct sk_buff *skb, int protocol,
203 const union nf_inet_addr *caddr, __be16 cport,
204 const union nf_inet_addr *vaddr, __be16 vport,
205 struct ip_vs_conn_param *p)
207 ip_vs_conn_fill_param(svc->net, svc->af, protocol, caddr, cport, vaddr,
210 if (p->pe && p->pe->fill_param)
211 return p->pe->fill_param(p, skb);
217 * IPVS persistent scheduling function
218 * It creates a connection entry according to its template if exists,
219 * or selects a server and creates a connection entry plus a template.
220 * Locking: we are svc user (svc->refcnt), so we hold all dests too
221 * Protocols supported: TCP, UDP
223 static struct ip_vs_conn *
224 ip_vs_sched_persist(struct ip_vs_service *svc,
226 __be16 src_port, __be16 dst_port, int *ignored)
228 struct ip_vs_conn *cp = NULL;
229 struct ip_vs_iphdr iph;
230 struct ip_vs_dest *dest;
231 struct ip_vs_conn *ct;
232 __be16 dport = 0; /* destination port to forward */
234 struct ip_vs_conn_param param;
235 const union nf_inet_addr fwmark = { .ip = htonl(svc->fwmark) };
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;
273 if (dst_port == svc->port) {
275 * <protocol, caddr, 0, vaddr, vport, daddr, dport>
277 * <protocol, caddr, 0, vaddr, 0, daddr, 0>
279 if (svc->port != FTPPORT)
282 /* Note: persistent fwmark-based services and
283 * persistent port zero service are handled here.
285 * <IPPROTO_IP,caddr,0,fwmark,0,daddr,0>
286 * port zero template:
287 * <protocol,caddr,0,vaddr,0,daddr,0>
290 protocol = IPPROTO_IP;
294 /* return *ignored = -1 so NF_DROP can be used */
295 if (ip_vs_conn_fill_param_persist(svc, skb, protocol, &snet, 0,
296 vaddr, vport, ¶m) < 0) {
302 /* Check if a template already exists */
303 ct = ip_vs_ct_in_get(¶m);
304 if (!ct || !ip_vs_check_template(ct)) {
306 * No template found or the dest of the connection
307 * template is not available.
308 * return *ignored=0 i.e. ICMP and NF_DROP
310 dest = svc->scheduler->schedule(svc, skb);
312 IP_VS_DBG(1, "p-schedule: no dest found.\n");
313 kfree(param.pe_data);
318 if (dst_port == svc->port && svc->port != FTPPORT)
322 * This adds param.pe_data to the template,
323 * and thus param.pe_data will be destroyed
324 * when the template expires */
325 ct = ip_vs_conn_new(¶m, &dest->addr, dport,
326 IP_VS_CONN_F_TEMPLATE, dest, skb->mark);
328 kfree(param.pe_data);
333 ct->timeout = svc->timeout;
335 /* set destination with the found template */
337 kfree(param.pe_data);
341 if (dport == svc->port && dest->port)
344 flags = (svc->flags & IP_VS_SVC_F_ONEPACKET
345 && iph.protocol == IPPROTO_UDP)?
346 IP_VS_CONN_F_ONE_PACKET : 0;
349 * Create a new connection according to the template
351 ip_vs_conn_fill_param(svc->net, svc->af, iph.protocol, &iph.saddr,
352 src_port, &iph.daddr, dst_port, ¶m);
354 cp = ip_vs_conn_new(¶m, &dest->addr, dport, flags, dest, skb->mark);
364 ip_vs_control_add(cp, ct);
367 ip_vs_conn_stats(cp, svc);
373 * IPVS main scheduling function
374 * It selects a server according to the virtual service, and
375 * creates a connection entry.
376 * Protocols supported: TCP, UDP
380 * 1 : protocol tried to schedule (eg. on SYN), found svc but the
381 * svc/scheduler decides that this packet should be accepted with
382 * NF_ACCEPT because it must not be scheduled.
384 * 0 : scheduler can not find destination, so try bypass or
385 * return ICMP and then NF_DROP (ip_vs_leave).
387 * -1 : scheduler tried to schedule but fatal error occurred, eg.
388 * ip_vs_conn_new failure (ENOMEM) or ip_vs_sip_fill_param
389 * failure such as missing Call-ID, ENOMEM on skb_linearize
390 * or pe_data. In this case we should return NF_DROP without
391 * any attempts to send ICMP with ip_vs_leave.
394 ip_vs_schedule(struct ip_vs_service *svc, struct sk_buff *skb,
395 struct ip_vs_proto_data *pd, int *ignored)
397 struct ip_vs_protocol *pp = pd->pp;
398 struct ip_vs_conn *cp = NULL;
399 struct ip_vs_iphdr iph;
400 struct ip_vs_dest *dest;
401 __be16 _ports[2], *pptr;
405 ip_vs_fill_iphdr(svc->af, skb_network_header(skb), &iph);
406 pptr = skb_header_pointer(skb, iph.len, sizeof(_ports), _ports);
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, iph.len, 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);
442 * Non-persistent service
444 if (!svc->fwmark && pptr[1] != svc->port) {
446 pr_err("Schedule: port zero only supported "
447 "in persistent services, "
448 "check your ipvs configuration\n");
452 dest = svc->scheduler->schedule(svc, skb);
454 IP_VS_DBG(1, "Schedule: no dest found.\n");
458 flags = (svc->flags & IP_VS_SVC_F_ONEPACKET
459 && iph.protocol == IPPROTO_UDP)?
460 IP_VS_CONN_F_ONE_PACKET : 0;
463 * Create a connection entry.
466 struct ip_vs_conn_param p;
468 ip_vs_conn_fill_param(svc->net, svc->af, iph.protocol,
469 &iph.saddr, pptr[0], &iph.daddr, pptr[1],
471 cp = ip_vs_conn_new(&p, &dest->addr,
472 dest->port ? dest->port : pptr[1],
473 flags, dest, skb->mark);
480 IP_VS_DBG_BUF(6, "Schedule fwd:%c c:%s:%u v:%s:%u "
481 "d:%s:%u conn->flags:%X conn->refcnt:%d\n",
483 IP_VS_DBG_ADDR(svc->af, &cp->caddr), ntohs(cp->cport),
484 IP_VS_DBG_ADDR(svc->af, &cp->vaddr), ntohs(cp->vport),
485 IP_VS_DBG_ADDR(svc->af, &cp->daddr), ntohs(cp->dport),
486 cp->flags, atomic_read(&cp->refcnt));
488 ip_vs_conn_stats(cp, svc);
494 * Pass or drop the packet.
495 * Called by ip_vs_in, when the virtual service is available but
496 * no destination is available for a new connection.
498 int ip_vs_leave(struct ip_vs_service *svc, struct sk_buff *skb,
499 struct ip_vs_proto_data *pd)
501 __be16 _ports[2], *pptr;
502 struct ip_vs_iphdr iph;
505 struct netns_ipvs *ipvs;
509 ip_vs_fill_iphdr(svc->af, skb_network_header(skb), &iph);
511 pptr = skb_header_pointer(skb, iph.len, sizeof(_ports), _ports);
513 ip_vs_service_put(svc);
520 #ifdef CONFIG_IP_VS_IPV6
521 if (svc->af == AF_INET6)
522 unicast = ipv6_addr_type(&iph.daddr.in6) & IPV6_ADDR_UNICAST;
525 unicast = (inet_addr_type(net, iph.daddr.ip) == RTN_UNICAST);
527 /* if it is fwmark-based service, the cache_bypass sysctl is up
528 and the destination is a non-local unicast, then create
529 a cache_bypass connection entry */
530 ipvs = net_ipvs(net);
531 if (ipvs->sysctl_cache_bypass && svc->fwmark && unicast) {
533 struct ip_vs_conn *cp;
534 unsigned int flags = (svc->flags & IP_VS_SVC_F_ONEPACKET &&
535 iph.protocol == IPPROTO_UDP)?
536 IP_VS_CONN_F_ONE_PACKET : 0;
537 union nf_inet_addr daddr = { .all = { 0, 0, 0, 0 } };
539 ip_vs_service_put(svc);
541 /* create a new connection entry */
542 IP_VS_DBG(6, "%s(): create a cache_bypass entry\n", __func__);
544 struct ip_vs_conn_param p;
545 ip_vs_conn_fill_param(svc->net, svc->af, iph.protocol,
547 &iph.daddr, pptr[1], &p);
548 cp = ip_vs_conn_new(&p, &daddr, 0,
549 IP_VS_CONN_F_BYPASS | flags,
556 ip_vs_in_stats(cp, skb);
559 ip_vs_set_state(cp, IP_VS_DIR_INPUT, skb, pd);
561 /* transmit the first SYN packet */
562 ret = cp->packet_xmit(skb, cp, pd->pp);
563 /* do not touch skb anymore */
565 atomic_inc(&cp->in_pkts);
572 * When the virtual ftp service is presented, packets destined
573 * for other services on the VIP may get here (except services
574 * listed in the ipvs table), pass the packets, because it is
575 * not ipvs job to decide to drop the packets.
577 if ((svc->port == FTPPORT) && (pptr[1] != FTPPORT)) {
578 ip_vs_service_put(svc);
582 ip_vs_service_put(svc);
585 * Notify the client that the destination is unreachable, and
586 * release the socket buffer.
587 * Since it is in IP layer, the TCP socket is not actually
588 * created, the TCP RST packet cannot be sent, instead that
589 * ICMP_PORT_UNREACH is sent here no matter it is TCP/UDP. --WZ
591 #ifdef CONFIG_IP_VS_IPV6
592 if (svc->af == AF_INET6) {
594 struct net *net = dev_net(skb_dst(skb)->dev);
596 skb->dev = net->loopback_dev;
598 icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
601 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
608 static int sysctl_snat_reroute(struct sk_buff *skb)
610 struct netns_ipvs *ipvs = net_ipvs(skb_net(skb));
611 return ipvs->sysctl_snat_reroute;
614 static int sysctl_nat_icmp_send(struct net *net)
616 struct netns_ipvs *ipvs = net_ipvs(net);
617 return ipvs->sysctl_nat_icmp_send;
620 static int sysctl_expire_nodest_conn(struct netns_ipvs *ipvs)
622 return ipvs->sysctl_expire_nodest_conn;
627 static int sysctl_snat_reroute(struct sk_buff *skb) { return 0; }
628 static int sysctl_nat_icmp_send(struct net *net) { return 0; }
629 static int sysctl_expire_nodest_conn(struct netns_ipvs *ipvs) { return 0; }
633 __sum16 ip_vs_checksum_complete(struct sk_buff *skb, int offset)
635 return csum_fold(skb_checksum(skb, offset, skb->len - offset, 0));
638 static inline enum ip_defrag_users ip_vs_defrag_user(unsigned int hooknum)
640 if (NF_INET_LOCAL_IN == hooknum)
641 return IP_DEFRAG_VS_IN;
642 if (NF_INET_FORWARD == hooknum)
643 return IP_DEFRAG_VS_FWD;
644 return IP_DEFRAG_VS_OUT;
647 static inline int ip_vs_gather_frags(struct sk_buff *skb, u_int32_t user)
649 int err = ip_defrag(skb, user);
652 ip_send_check(ip_hdr(skb));
657 #ifdef CONFIG_IP_VS_IPV6
658 static inline int ip_vs_gather_frags_v6(struct sk_buff *skb, u_int32_t user)
660 /* TODO IPv6: Find out what to do here for IPv6 */
665 static int ip_vs_route_me_harder(int af, struct sk_buff *skb)
667 #ifdef CONFIG_IP_VS_IPV6
668 if (af == AF_INET6) {
669 if (sysctl_snat_reroute(skb) && ip6_route_me_harder(skb) != 0)
673 if ((sysctl_snat_reroute(skb) ||
674 skb_rtable(skb)->rt_flags & RTCF_LOCAL) &&
675 ip_route_me_harder(skb, RTN_LOCAL) != 0)
682 * Packet has been made sufficiently writable in caller
683 * - inout: 1=in->out, 0=out->in
685 void ip_vs_nat_icmp(struct sk_buff *skb, struct ip_vs_protocol *pp,
686 struct ip_vs_conn *cp, int inout)
688 struct iphdr *iph = ip_hdr(skb);
689 unsigned int icmp_offset = iph->ihl*4;
690 struct icmphdr *icmph = (struct icmphdr *)(skb_network_header(skb) +
692 struct iphdr *ciph = (struct iphdr *)(icmph + 1);
695 iph->saddr = cp->vaddr.ip;
697 ciph->daddr = cp->vaddr.ip;
700 iph->daddr = cp->daddr.ip;
702 ciph->saddr = cp->daddr.ip;
706 /* the TCP/UDP/SCTP port */
707 if (IPPROTO_TCP == ciph->protocol || IPPROTO_UDP == ciph->protocol ||
708 IPPROTO_SCTP == ciph->protocol) {
709 __be16 *ports = (void *)ciph + ciph->ihl*4;
712 ports[1] = cp->vport;
714 ports[0] = cp->dport;
717 /* And finally the ICMP checksum */
719 icmph->checksum = ip_vs_checksum_complete(skb, icmp_offset);
720 skb->ip_summed = CHECKSUM_UNNECESSARY;
723 IP_VS_DBG_PKT(11, AF_INET, pp, skb, (void *)ciph - (void *)iph,
724 "Forwarding altered outgoing ICMP");
726 IP_VS_DBG_PKT(11, AF_INET, pp, skb, (void *)ciph - (void *)iph,
727 "Forwarding altered incoming ICMP");
730 #ifdef CONFIG_IP_VS_IPV6
731 void ip_vs_nat_icmp_v6(struct sk_buff *skb, struct ip_vs_protocol *pp,
732 struct ip_vs_conn *cp, int inout)
734 struct ipv6hdr *iph = ipv6_hdr(skb);
735 unsigned int icmp_offset = sizeof(struct ipv6hdr);
736 struct icmp6hdr *icmph = (struct icmp6hdr *)(skb_network_header(skb) +
738 struct ipv6hdr *ciph = (struct ipv6hdr *)(icmph + 1);
741 iph->saddr = cp->vaddr.in6;
742 ciph->daddr = cp->vaddr.in6;
744 iph->daddr = cp->daddr.in6;
745 ciph->saddr = cp->daddr.in6;
748 /* the TCP/UDP/SCTP port */
749 if (IPPROTO_TCP == ciph->nexthdr || IPPROTO_UDP == ciph->nexthdr ||
750 IPPROTO_SCTP == ciph->nexthdr) {
751 __be16 *ports = (void *)ciph + sizeof(struct ipv6hdr);
754 ports[1] = cp->vport;
756 ports[0] = cp->dport;
759 /* And finally the ICMP checksum */
760 icmph->icmp6_cksum = ~csum_ipv6_magic(&iph->saddr, &iph->daddr,
761 skb->len - icmp_offset,
763 skb->csum_start = skb_network_header(skb) - skb->head + icmp_offset;
764 skb->csum_offset = offsetof(struct icmp6hdr, icmp6_cksum);
765 skb->ip_summed = CHECKSUM_PARTIAL;
768 IP_VS_DBG_PKT(11, AF_INET6, pp, skb,
769 (void *)ciph - (void *)iph,
770 "Forwarding altered outgoing ICMPv6");
772 IP_VS_DBG_PKT(11, AF_INET6, pp, skb,
773 (void *)ciph - (void *)iph,
774 "Forwarding altered incoming ICMPv6");
778 /* Handle relevant response ICMP messages - forward to the right
781 static int handle_response_icmp(int af, struct sk_buff *skb,
782 union nf_inet_addr *snet,
783 __u8 protocol, struct ip_vs_conn *cp,
784 struct ip_vs_protocol *pp,
785 unsigned int offset, unsigned int ihl)
787 unsigned int verdict = NF_DROP;
789 if (IP_VS_FWD_METHOD(cp) != 0) {
790 pr_err("shouldn't reach here, because the box is on the "
791 "half connection in the tun/dr module.\n");
794 /* Ensure the checksum is correct */
795 if (!skb_csum_unnecessary(skb) && ip_vs_checksum_complete(skb, ihl)) {
796 /* Failed checksum! */
797 IP_VS_DBG_BUF(1, "Forward ICMP: failed checksum from %s!\n",
798 IP_VS_DBG_ADDR(af, snet));
802 if (IPPROTO_TCP == protocol || IPPROTO_UDP == protocol ||
803 IPPROTO_SCTP == protocol)
804 offset += 2 * sizeof(__u16);
805 if (!skb_make_writable(skb, offset))
808 #ifdef CONFIG_IP_VS_IPV6
810 ip_vs_nat_icmp_v6(skb, pp, cp, 1);
813 ip_vs_nat_icmp(skb, pp, cp, 1);
815 if (ip_vs_route_me_harder(af, skb))
818 /* do the statistics and put it back */
819 ip_vs_out_stats(cp, skb);
821 skb->ipvs_property = 1;
822 if (!(cp->flags & IP_VS_CONN_F_NFCT))
825 ip_vs_update_conntrack(skb, cp, 0);
829 __ip_vs_conn_put(cp);
835 * Handle ICMP messages in the inside-to-outside direction (outgoing).
836 * Find any that might be relevant, check against existing connections.
837 * Currently handles error types - unreachable, quench, ttl exceeded.
839 static int ip_vs_out_icmp(struct sk_buff *skb, int *related,
840 unsigned int hooknum)
843 struct icmphdr _icmph, *ic;
844 struct iphdr _ciph, *cih; /* The ip header contained within the ICMP */
845 struct ip_vs_iphdr ciph;
846 struct ip_vs_conn *cp;
847 struct ip_vs_protocol *pp;
848 unsigned int offset, ihl;
849 union nf_inet_addr snet;
853 /* reassemble IP fragments */
854 if (ip_is_fragment(ip_hdr(skb))) {
855 if (ip_vs_gather_frags(skb, ip_vs_defrag_user(hooknum)))
860 offset = ihl = iph->ihl * 4;
861 ic = skb_header_pointer(skb, offset, sizeof(_icmph), &_icmph);
865 IP_VS_DBG(12, "Outgoing ICMP (%d,%d) %pI4->%pI4\n",
866 ic->type, ntohs(icmp_id(ic)),
867 &iph->saddr, &iph->daddr);
870 * Work through seeing if this is for us.
871 * These checks are supposed to be in an order that means easy
872 * things are checked first to speed up processing.... however
873 * this means that some packets will manage to get a long way
874 * down this stack and then be rejected, but that's life.
876 if ((ic->type != ICMP_DEST_UNREACH) &&
877 (ic->type != ICMP_SOURCE_QUENCH) &&
878 (ic->type != ICMP_TIME_EXCEEDED)) {
883 /* Now find the contained IP header */
884 offset += sizeof(_icmph);
885 cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
887 return NF_ACCEPT; /* The packet looks wrong, ignore */
889 pp = ip_vs_proto_get(cih->protocol);
893 /* Is the embedded protocol header present? */
894 if (unlikely(cih->frag_off & htons(IP_OFFSET) &&
898 IP_VS_DBG_PKT(11, AF_INET, pp, skb, offset,
899 "Checking outgoing ICMP for");
901 offset += cih->ihl * 4;
903 ip_vs_fill_iphdr(AF_INET, cih, &ciph);
904 /* The embedded headers contain source and dest in reverse order */
905 cp = pp->conn_out_get(AF_INET, skb, &ciph, offset, 1);
909 snet.ip = iph->saddr;
910 return handle_response_icmp(AF_INET, skb, &snet, cih->protocol, cp,
914 #ifdef CONFIG_IP_VS_IPV6
915 static int ip_vs_out_icmp_v6(struct sk_buff *skb, int *related,
916 unsigned int hooknum)
919 struct icmp6hdr _icmph, *ic;
920 struct ipv6hdr _ciph, *cih; /* The ip header contained
922 struct ip_vs_iphdr ciph;
923 struct ip_vs_conn *cp;
924 struct ip_vs_protocol *pp;
926 union nf_inet_addr snet;
930 /* reassemble IP fragments */
931 if (ipv6_hdr(skb)->nexthdr == IPPROTO_FRAGMENT) {
932 if (ip_vs_gather_frags_v6(skb, ip_vs_defrag_user(hooknum)))
937 offset = sizeof(struct ipv6hdr);
938 ic = skb_header_pointer(skb, offset, sizeof(_icmph), &_icmph);
942 IP_VS_DBG(12, "Outgoing ICMPv6 (%d,%d) %pI6->%pI6\n",
943 ic->icmp6_type, ntohs(icmpv6_id(ic)),
944 &iph->saddr, &iph->daddr);
947 * Work through seeing if this is for us.
948 * These checks are supposed to be in an order that means easy
949 * things are checked first to speed up processing.... however
950 * this means that some packets will manage to get a long way
951 * down this stack and then be rejected, but that's life.
953 if ((ic->icmp6_type != ICMPV6_DEST_UNREACH) &&
954 (ic->icmp6_type != ICMPV6_PKT_TOOBIG) &&
955 (ic->icmp6_type != ICMPV6_TIME_EXCEED)) {
960 /* Now find the contained IP header */
961 offset += sizeof(_icmph);
962 cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
964 return NF_ACCEPT; /* The packet looks wrong, ignore */
966 pp = ip_vs_proto_get(cih->nexthdr);
970 /* Is the embedded protocol header present? */
971 /* TODO: we don't support fragmentation at the moment anyways */
972 if (unlikely(cih->nexthdr == IPPROTO_FRAGMENT && pp->dont_defrag))
975 IP_VS_DBG_PKT(11, AF_INET6, pp, skb, offset,
976 "Checking outgoing ICMPv6 for");
978 offset += sizeof(struct ipv6hdr);
980 ip_vs_fill_iphdr(AF_INET6, cih, &ciph);
981 /* The embedded headers contain source and dest in reverse order */
982 cp = pp->conn_out_get(AF_INET6, skb, &ciph, offset, 1);
986 snet.in6 = iph->saddr;
987 return handle_response_icmp(AF_INET6, skb, &snet, cih->nexthdr, cp,
988 pp, offset, sizeof(struct ipv6hdr));
993 * Check if sctp chunc is ABORT chunk
995 static inline int is_sctp_abort(const struct sk_buff *skb, int nh_len)
997 sctp_chunkhdr_t *sch, schunk;
998 sch = skb_header_pointer(skb, nh_len + sizeof(sctp_sctphdr_t),
999 sizeof(schunk), &schunk);
1002 if (sch->type == SCTP_CID_ABORT)
1007 static inline int is_tcp_reset(const struct sk_buff *skb, int nh_len)
1009 struct tcphdr _tcph, *th;
1011 th = skb_header_pointer(skb, nh_len, sizeof(_tcph), &_tcph);
1017 /* Handle response packets: rewrite addresses and send away...
1020 handle_response(int af, struct sk_buff *skb, struct ip_vs_proto_data *pd,
1021 struct ip_vs_conn *cp, int ihl)
1023 struct ip_vs_protocol *pp = pd->pp;
1025 IP_VS_DBG_PKT(11, af, pp, skb, 0, "Outgoing packet");
1027 if (!skb_make_writable(skb, ihl))
1030 /* mangle the packet */
1031 if (pp->snat_handler && !pp->snat_handler(skb, pp, cp))
1034 #ifdef CONFIG_IP_VS_IPV6
1036 ipv6_hdr(skb)->saddr = cp->vaddr.in6;
1040 ip_hdr(skb)->saddr = cp->vaddr.ip;
1041 ip_send_check(ip_hdr(skb));
1045 * nf_iterate does not expect change in the skb->dst->dev.
1046 * It looks like it is not fatal to enable this code for hooks
1047 * where our handlers are at the end of the chain list and
1048 * when all next handlers use skb->dst->dev and not outdev.
1049 * It will definitely route properly the inout NAT traffic
1050 * when multiple paths are used.
1053 /* For policy routing, packets originating from this
1054 * machine itself may be routed differently to packets
1055 * passing through. We want this packet to be routed as
1056 * if it came from this machine itself. So re-compute
1057 * the routing information.
1059 if (ip_vs_route_me_harder(af, skb))
1062 IP_VS_DBG_PKT(10, af, pp, skb, 0, "After SNAT");
1064 ip_vs_out_stats(cp, skb);
1065 ip_vs_set_state(cp, IP_VS_DIR_OUTPUT, skb, pd);
1066 skb->ipvs_property = 1;
1067 if (!(cp->flags & IP_VS_CONN_F_NFCT))
1070 ip_vs_update_conntrack(skb, cp, 0);
1084 * Check if outgoing packet belongs to the established ip_vs_conn.
1087 ip_vs_out(unsigned int hooknum, struct sk_buff *skb, int af)
1089 struct net *net = NULL;
1090 struct ip_vs_iphdr iph;
1091 struct ip_vs_protocol *pp;
1092 struct ip_vs_proto_data *pd;
1093 struct ip_vs_conn *cp;
1097 /* Already marked as IPVS request or reply? */
1098 if (skb->ipvs_property)
1101 /* Bad... Do not break raw sockets */
1102 if (unlikely(skb->sk != NULL && hooknum == NF_INET_LOCAL_OUT &&
1104 struct sock *sk = skb->sk;
1105 struct inet_sock *inet = inet_sk(skb->sk);
1107 if (inet && sk->sk_family == PF_INET && inet->nodefrag)
1111 if (unlikely(!skb_dst(skb)))
1115 if (!net_ipvs(net)->enable)
1118 ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
1119 #ifdef CONFIG_IP_VS_IPV6
1120 if (af == AF_INET6) {
1121 if (unlikely(iph.protocol == IPPROTO_ICMPV6)) {
1123 int verdict = ip_vs_out_icmp_v6(skb, &related,
1128 ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
1132 if (unlikely(iph.protocol == IPPROTO_ICMP)) {
1134 int verdict = ip_vs_out_icmp(skb, &related, hooknum);
1138 ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
1141 pd = ip_vs_proto_data_get(net, iph.protocol);
1146 /* reassemble IP fragments */
1147 #ifdef CONFIG_IP_VS_IPV6
1148 if (af == AF_INET6) {
1149 if (ipv6_hdr(skb)->nexthdr == IPPROTO_FRAGMENT) {
1150 if (ip_vs_gather_frags_v6(skb,
1151 ip_vs_defrag_user(hooknum)))
1155 ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
1158 if (unlikely(ip_is_fragment(ip_hdr(skb)) && !pp->dont_defrag)) {
1159 if (ip_vs_gather_frags(skb,
1160 ip_vs_defrag_user(hooknum)))
1163 ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
1167 * Check if the packet belongs to an existing entry
1169 cp = pp->conn_out_get(af, skb, &iph, iph.len, 0);
1172 return handle_response(af, skb, pd, cp, iph.len);
1173 if (sysctl_nat_icmp_send(net) &&
1174 (pp->protocol == IPPROTO_TCP ||
1175 pp->protocol == IPPROTO_UDP ||
1176 pp->protocol == IPPROTO_SCTP)) {
1177 __be16 _ports[2], *pptr;
1179 pptr = skb_header_pointer(skb, iph.len,
1180 sizeof(_ports), _ports);
1182 return NF_ACCEPT; /* Not for me */
1183 if (ip_vs_lookup_real_service(net, af, iph.protocol,
1187 * Notify the real server: there is no
1188 * existing entry if it is not RST
1189 * packet or not TCP packet.
1191 if ((iph.protocol != IPPROTO_TCP &&
1192 iph.protocol != IPPROTO_SCTP)
1193 || ((iph.protocol == IPPROTO_TCP
1194 && !is_tcp_reset(skb, iph.len))
1195 || (iph.protocol == IPPROTO_SCTP
1196 && !is_sctp_abort(skb,
1198 #ifdef CONFIG_IP_VS_IPV6
1199 if (af == AF_INET6) {
1201 dev_net(skb_dst(skb)->dev);
1204 skb->dev = net->loopback_dev;
1206 ICMPV6_DEST_UNREACH,
1207 ICMPV6_PORT_UNREACH,
1213 ICMP_PORT_UNREACH, 0);
1218 IP_VS_DBG_PKT(12, af, pp, skb, 0,
1219 "ip_vs_out: packet continues traversal as normal");
1224 * It is hooked at the NF_INET_FORWARD and NF_INET_LOCAL_IN chain,
1225 * used only for VS/NAT.
1226 * Check if packet is reply for established ip_vs_conn.
1229 ip_vs_reply4(unsigned int hooknum, struct sk_buff *skb,
1230 const struct net_device *in, const struct net_device *out,
1231 int (*okfn)(struct sk_buff *))
1233 return ip_vs_out(hooknum, skb, AF_INET);
1237 * It is hooked at the NF_INET_LOCAL_OUT chain, used only for VS/NAT.
1238 * Check if packet is reply for established ip_vs_conn.
1241 ip_vs_local_reply4(unsigned int hooknum, struct sk_buff *skb,
1242 const struct net_device *in, const struct net_device *out,
1243 int (*okfn)(struct sk_buff *))
1245 unsigned int verdict;
1247 /* Disable BH in LOCAL_OUT until all places are fixed */
1249 verdict = ip_vs_out(hooknum, skb, AF_INET);
1254 #ifdef CONFIG_IP_VS_IPV6
1257 * It is hooked at the NF_INET_FORWARD and NF_INET_LOCAL_IN chain,
1258 * used only for VS/NAT.
1259 * Check if packet is reply for established ip_vs_conn.
1262 ip_vs_reply6(unsigned int hooknum, struct sk_buff *skb,
1263 const struct net_device *in, const struct net_device *out,
1264 int (*okfn)(struct sk_buff *))
1266 return ip_vs_out(hooknum, skb, AF_INET6);
1270 * It is hooked at the NF_INET_LOCAL_OUT chain, used only for VS/NAT.
1271 * Check if packet is reply for established ip_vs_conn.
1274 ip_vs_local_reply6(unsigned int hooknum, struct sk_buff *skb,
1275 const struct net_device *in, const struct net_device *out,
1276 int (*okfn)(struct sk_buff *))
1278 unsigned int verdict;
1280 /* Disable BH in LOCAL_OUT until all places are fixed */
1282 verdict = ip_vs_out(hooknum, skb, AF_INET6);
1290 * Handle ICMP messages in the outside-to-inside direction (incoming).
1291 * Find any that might be relevant, check against existing connections,
1292 * forward to the right destination host if relevant.
1293 * Currently handles error types - unreachable, quench, ttl exceeded.
1296 ip_vs_in_icmp(struct sk_buff *skb, int *related, unsigned int hooknum)
1298 struct net *net = NULL;
1300 struct icmphdr _icmph, *ic;
1301 struct iphdr _ciph, *cih; /* The ip header contained within the ICMP */
1302 struct ip_vs_iphdr ciph;
1303 struct ip_vs_conn *cp;
1304 struct ip_vs_protocol *pp;
1305 struct ip_vs_proto_data *pd;
1306 unsigned int offset, offset2, 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 /* Special case for errors for IPIP packets */
1351 if (cih->protocol == IPPROTO_IPIP) {
1352 if (unlikely(cih->frag_off & htons(IP_OFFSET)))
1354 /* Error for our IPIP must arrive at LOCAL_IN */
1355 if (!(skb_rtable(skb)->rt_flags & RTCF_LOCAL))
1357 offset += cih->ihl * 4;
1358 cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
1360 return NF_ACCEPT; /* The packet looks wrong, ignore */
1364 pd = ip_vs_proto_data_get(net, cih->protocol);
1369 /* Is the embedded protocol header present? */
1370 if (unlikely(cih->frag_off & htons(IP_OFFSET) &&
1374 IP_VS_DBG_PKT(11, AF_INET, pp, skb, offset,
1375 "Checking incoming ICMP for");
1378 offset += cih->ihl * 4;
1380 ip_vs_fill_iphdr(AF_INET, cih, &ciph);
1381 /* The embedded headers contain source and dest in reverse order.
1382 * For IPIP this is error for request, not for reply.
1384 cp = pp->conn_in_get(AF_INET, skb, &ciph, offset, ipip ? 0 : 1);
1390 /* Ensure the checksum is correct */
1391 if (!skb_csum_unnecessary(skb) && ip_vs_checksum_complete(skb, ihl)) {
1392 /* Failed checksum! */
1393 IP_VS_DBG(1, "Incoming ICMP: failed checksum from %pI4!\n",
1399 __be32 info = ic->un.gateway;
1401 /* Update the MTU */
1402 if (ic->type == ICMP_DEST_UNREACH &&
1403 ic->code == ICMP_FRAG_NEEDED) {
1404 struct ip_vs_dest *dest = cp->dest;
1405 u32 mtu = ntohs(ic->un.frag.mtu);
1407 /* Strip outer IP and ICMP, go to IPIP header */
1408 __skb_pull(skb, ihl + sizeof(_icmph));
1409 offset2 -= ihl + sizeof(_icmph);
1410 skb_reset_network_header(skb);
1411 IP_VS_DBG(12, "ICMP for IPIP %pI4->%pI4: mtu=%u\n",
1412 &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr, mtu);
1414 ipv4_update_pmtu(skb, dev_net(skb->dev),
1417 /* Client uses PMTUD? */
1418 if (!(cih->frag_off & htons(IP_DF)))
1420 /* Prefer the resulting PMTU */
1422 spin_lock(&dest->dst_lock);
1423 if (dest->dst_cache)
1424 mtu = dst_mtu(dest->dst_cache);
1425 spin_unlock(&dest->dst_lock);
1427 if (mtu > 68 + sizeof(struct iphdr))
1428 mtu -= sizeof(struct iphdr);
1431 /* Strip outer IP, ICMP and IPIP, go to IP header of
1434 __skb_pull(skb, offset2);
1435 skb_reset_network_header(skb);
1436 IP_VS_DBG(12, "Sending ICMP for %pI4->%pI4: t=%u, c=%u, i=%u\n",
1437 &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr,
1438 ic->type, ic->code, ntohl(info));
1439 icmp_send(skb, ic->type, ic->code, info);
1440 /* ICMP can be shorter but anyways, account it */
1441 ip_vs_out_stats(cp, skb);
1445 verdict = NF_STOLEN;
1449 /* do the statistics and put it back */
1450 ip_vs_in_stats(cp, skb);
1451 if (IPPROTO_TCP == cih->protocol || IPPROTO_UDP == cih->protocol)
1452 offset += 2 * sizeof(__u16);
1453 verdict = ip_vs_icmp_xmit(skb, cp, pp, offset, hooknum);
1456 __ip_vs_conn_put(cp);
1461 #ifdef CONFIG_IP_VS_IPV6
1463 ip_vs_in_icmp_v6(struct sk_buff *skb, int *related, unsigned int hooknum)
1465 struct net *net = NULL;
1466 struct ipv6hdr *iph;
1467 struct icmp6hdr _icmph, *ic;
1468 struct ipv6hdr _ciph, *cih; /* The ip header contained
1470 struct ip_vs_iphdr ciph;
1471 struct ip_vs_conn *cp;
1472 struct ip_vs_protocol *pp;
1473 struct ip_vs_proto_data *pd;
1474 unsigned int offset, verdict;
1478 /* reassemble IP fragments */
1479 if (ipv6_hdr(skb)->nexthdr == IPPROTO_FRAGMENT) {
1480 if (ip_vs_gather_frags_v6(skb, ip_vs_defrag_user(hooknum)))
1484 iph = ipv6_hdr(skb);
1485 offset = sizeof(struct ipv6hdr);
1486 ic = skb_header_pointer(skb, offset, sizeof(_icmph), &_icmph);
1490 IP_VS_DBG(12, "Incoming ICMPv6 (%d,%d) %pI6->%pI6\n",
1491 ic->icmp6_type, ntohs(icmpv6_id(ic)),
1492 &iph->saddr, &iph->daddr);
1495 * Work through seeing if this is for us.
1496 * These checks are supposed to be in an order that means easy
1497 * things are checked first to speed up processing.... however
1498 * this means that some packets will manage to get a long way
1499 * down this stack and then be rejected, but that's life.
1501 if ((ic->icmp6_type != ICMPV6_DEST_UNREACH) &&
1502 (ic->icmp6_type != ICMPV6_PKT_TOOBIG) &&
1503 (ic->icmp6_type != ICMPV6_TIME_EXCEED)) {
1508 /* Now find the contained IP header */
1509 offset += sizeof(_icmph);
1510 cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
1512 return NF_ACCEPT; /* The packet looks wrong, ignore */
1515 pd = ip_vs_proto_data_get(net, cih->nexthdr);
1520 /* Is the embedded protocol header present? */
1521 /* TODO: we don't support fragmentation at the moment anyways */
1522 if (unlikely(cih->nexthdr == IPPROTO_FRAGMENT && pp->dont_defrag))
1525 IP_VS_DBG_PKT(11, AF_INET6, pp, skb, offset,
1526 "Checking incoming ICMPv6 for");
1528 offset += sizeof(struct ipv6hdr);
1530 ip_vs_fill_iphdr(AF_INET6, cih, &ciph);
1531 /* The embedded headers contain source and dest in reverse order */
1532 cp = pp->conn_in_get(AF_INET6, skb, &ciph, offset, 1);
1536 /* do the statistics and put it back */
1537 ip_vs_in_stats(cp, skb);
1538 if (IPPROTO_TCP == cih->nexthdr || IPPROTO_UDP == cih->nexthdr ||
1539 IPPROTO_SCTP == cih->nexthdr)
1540 offset += 2 * sizeof(__u16);
1541 verdict = ip_vs_icmp_xmit_v6(skb, cp, pp, offset, hooknum);
1543 __ip_vs_conn_put(cp);
1551 * Check if it's for virtual services, look it up,
1552 * and send it on its way...
1555 ip_vs_in(unsigned int hooknum, struct sk_buff *skb, int af)
1558 struct ip_vs_iphdr iph;
1559 struct ip_vs_protocol *pp;
1560 struct ip_vs_proto_data *pd;
1561 struct ip_vs_conn *cp;
1563 struct netns_ipvs *ipvs;
1565 /* Already marked as IPVS request or reply? */
1566 if (skb->ipvs_property)
1571 * - remote client: only PACKET_HOST
1572 * - route: used for struct net when skb->dev is unset
1574 if (unlikely((skb->pkt_type != PACKET_HOST &&
1575 hooknum != NF_INET_LOCAL_OUT) ||
1577 ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
1578 IP_VS_DBG_BUF(12, "packet type=%d proto=%d daddr=%s"
1579 " ignored in hook %u\n",
1580 skb->pkt_type, iph.protocol,
1581 IP_VS_DBG_ADDR(af, &iph.daddr), hooknum);
1584 /* ipvs enabled in this netns ? */
1586 if (!net_ipvs(net)->enable)
1589 ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
1591 /* Bad... Do not break raw sockets */
1592 if (unlikely(skb->sk != NULL && hooknum == NF_INET_LOCAL_OUT &&
1594 struct sock *sk = skb->sk;
1595 struct inet_sock *inet = inet_sk(skb->sk);
1597 if (inet && sk->sk_family == PF_INET && inet->nodefrag)
1601 #ifdef CONFIG_IP_VS_IPV6
1602 if (af == AF_INET6) {
1603 if (unlikely(iph.protocol == IPPROTO_ICMPV6)) {
1605 int verdict = ip_vs_in_icmp_v6(skb, &related, hooknum);
1609 ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
1613 if (unlikely(iph.protocol == IPPROTO_ICMP)) {
1615 int verdict = ip_vs_in_icmp(skb, &related, hooknum);
1619 ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
1622 /* Protocol supported? */
1623 pd = ip_vs_proto_data_get(net, iph.protocol);
1628 * Check if the packet belongs to an existing connection entry
1630 cp = pp->conn_in_get(af, skb, &iph, iph.len, 0);
1632 if (unlikely(!cp)) {
1635 if (!pp->conn_schedule(af, skb, pd, &v, &cp))
1639 if (unlikely(!cp)) {
1640 /* sorry, all this trouble for a no-hit :) */
1641 IP_VS_DBG_PKT(12, af, pp, skb, 0,
1642 "ip_vs_in: packet continues traversal as normal");
1646 IP_VS_DBG_PKT(11, af, pp, skb, 0, "Incoming packet");
1647 ipvs = net_ipvs(net);
1648 /* Check the server status */
1649 if (cp->dest && !(cp->dest->flags & IP_VS_DEST_F_AVAILABLE)) {
1650 /* the destination server is not available */
1652 if (sysctl_expire_nodest_conn(ipvs)) {
1653 /* try to expire the connection immediately */
1654 ip_vs_conn_expire_now(cp);
1656 /* don't restart its timer, and silently
1658 __ip_vs_conn_put(cp);
1662 ip_vs_in_stats(cp, skb);
1663 ip_vs_set_state(cp, IP_VS_DIR_INPUT, skb, pd);
1664 if (cp->packet_xmit)
1665 ret = cp->packet_xmit(skb, cp, pp);
1666 /* do not touch skb anymore */
1668 IP_VS_DBG_RL("warning: packet_xmit is null");
1672 /* Increase its packet counter and check if it is needed
1673 * to be synchronized
1675 * Sync connection if it is about to close to
1676 * encorage the standby servers to update the connections timeout
1678 * For ONE_PKT let ip_vs_sync_conn() do the filter work.
1681 if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
1682 pkts = sysctl_sync_threshold(ipvs);
1684 pkts = atomic_add_return(1, &cp->in_pkts);
1686 if (ipvs->sync_state & IP_VS_STATE_MASTER)
1687 ip_vs_sync_conn(net, cp, pkts);
1694 * AF_INET handler in NF_INET_LOCAL_IN chain
1695 * Schedule and forward packets from remote clients
1698 ip_vs_remote_request4(unsigned int hooknum, struct sk_buff *skb,
1699 const struct net_device *in,
1700 const struct net_device *out,
1701 int (*okfn)(struct sk_buff *))
1703 return ip_vs_in(hooknum, skb, AF_INET);
1707 * AF_INET handler in NF_INET_LOCAL_OUT chain
1708 * Schedule and forward packets from local clients
1711 ip_vs_local_request4(unsigned int hooknum, struct sk_buff *skb,
1712 const struct net_device *in, const struct net_device *out,
1713 int (*okfn)(struct sk_buff *))
1715 unsigned int verdict;
1717 /* Disable BH in LOCAL_OUT until all places are fixed */
1719 verdict = ip_vs_in(hooknum, skb, AF_INET);
1724 #ifdef CONFIG_IP_VS_IPV6
1727 * AF_INET6 handler in NF_INET_LOCAL_IN chain
1728 * Schedule and forward packets from remote clients
1731 ip_vs_remote_request6(unsigned int hooknum, struct sk_buff *skb,
1732 const struct net_device *in,
1733 const struct net_device *out,
1734 int (*okfn)(struct sk_buff *))
1736 return ip_vs_in(hooknum, skb, AF_INET6);
1740 * AF_INET6 handler in NF_INET_LOCAL_OUT chain
1741 * Schedule and forward packets from local clients
1744 ip_vs_local_request6(unsigned int hooknum, struct sk_buff *skb,
1745 const struct net_device *in, const struct net_device *out,
1746 int (*okfn)(struct sk_buff *))
1748 unsigned int verdict;
1750 /* Disable BH in LOCAL_OUT until all places are fixed */
1752 verdict = ip_vs_in(hooknum, skb, AF_INET6);
1761 * It is hooked at the NF_INET_FORWARD chain, in order to catch ICMP
1762 * related packets destined for 0.0.0.0/0.
1763 * When fwmark-based virtual service is used, such as transparent
1764 * cache cluster, TCP packets can be marked and routed to ip_vs_in,
1765 * but ICMP destined for 0.0.0.0/0 cannot not be easily marked and
1766 * sent to ip_vs_in_icmp. So, catch them at the NF_INET_FORWARD chain
1767 * and send them to ip_vs_in_icmp.
1770 ip_vs_forward_icmp(unsigned int hooknum, struct sk_buff *skb,
1771 const struct net_device *in, const struct net_device *out,
1772 int (*okfn)(struct sk_buff *))
1777 if (ip_hdr(skb)->protocol != IPPROTO_ICMP)
1780 /* ipvs enabled in this netns ? */
1782 if (!net_ipvs(net)->enable)
1785 return ip_vs_in_icmp(skb, &r, hooknum);
1788 #ifdef CONFIG_IP_VS_IPV6
1790 ip_vs_forward_icmp_v6(unsigned int hooknum, struct sk_buff *skb,
1791 const struct net_device *in, const struct net_device *out,
1792 int (*okfn)(struct sk_buff *))
1797 if (ipv6_hdr(skb)->nexthdr != IPPROTO_ICMPV6)
1800 /* ipvs enabled in this netns ? */
1802 if (!net_ipvs(net)->enable)
1805 return ip_vs_in_icmp_v6(skb, &r, hooknum);
1810 static struct nf_hook_ops ip_vs_ops[] __read_mostly = {
1811 /* After packet filtering, change source only for VS/NAT */
1813 .hook = ip_vs_reply4,
1814 .owner = THIS_MODULE,
1816 .hooknum = NF_INET_LOCAL_IN,
1817 .priority = NF_IP_PRI_NAT_SRC - 2,
1819 /* After packet filtering, forward packet through VS/DR, VS/TUN,
1820 * or VS/NAT(change destination), so that filtering rules can be
1821 * applied to IPVS. */
1823 .hook = ip_vs_remote_request4,
1824 .owner = THIS_MODULE,
1826 .hooknum = NF_INET_LOCAL_IN,
1827 .priority = NF_IP_PRI_NAT_SRC - 1,
1829 /* Before ip_vs_in, change source only for VS/NAT */
1831 .hook = ip_vs_local_reply4,
1832 .owner = THIS_MODULE,
1834 .hooknum = NF_INET_LOCAL_OUT,
1835 .priority = NF_IP_PRI_NAT_DST + 1,
1837 /* After mangle, schedule and forward local requests */
1839 .hook = ip_vs_local_request4,
1840 .owner = THIS_MODULE,
1842 .hooknum = NF_INET_LOCAL_OUT,
1843 .priority = NF_IP_PRI_NAT_DST + 2,
1845 /* After packet filtering (but before ip_vs_out_icmp), catch icmp
1846 * destined for 0.0.0.0/0, which is for incoming IPVS connections */
1848 .hook = ip_vs_forward_icmp,
1849 .owner = THIS_MODULE,
1851 .hooknum = NF_INET_FORWARD,
1854 /* After packet filtering, change source only for VS/NAT */
1856 .hook = ip_vs_reply4,
1857 .owner = THIS_MODULE,
1859 .hooknum = NF_INET_FORWARD,
1862 #ifdef CONFIG_IP_VS_IPV6
1863 /* After packet filtering, change source only for VS/NAT */
1865 .hook = ip_vs_reply6,
1866 .owner = THIS_MODULE,
1868 .hooknum = NF_INET_LOCAL_IN,
1869 .priority = NF_IP6_PRI_NAT_SRC - 2,
1871 /* After packet filtering, forward packet through VS/DR, VS/TUN,
1872 * or VS/NAT(change destination), so that filtering rules can be
1873 * applied to IPVS. */
1875 .hook = ip_vs_remote_request6,
1876 .owner = THIS_MODULE,
1878 .hooknum = NF_INET_LOCAL_IN,
1879 .priority = NF_IP6_PRI_NAT_SRC - 1,
1881 /* Before ip_vs_in, change source only for VS/NAT */
1883 .hook = ip_vs_local_reply6,
1884 .owner = THIS_MODULE,
1886 .hooknum = NF_INET_LOCAL_OUT,
1887 .priority = NF_IP6_PRI_NAT_DST + 1,
1889 /* After mangle, schedule and forward local requests */
1891 .hook = ip_vs_local_request6,
1892 .owner = THIS_MODULE,
1894 .hooknum = NF_INET_LOCAL_OUT,
1895 .priority = NF_IP6_PRI_NAT_DST + 2,
1897 /* After packet filtering (but before ip_vs_out_icmp), catch icmp
1898 * destined for 0.0.0.0/0, which is for incoming IPVS connections */
1900 .hook = ip_vs_forward_icmp_v6,
1901 .owner = THIS_MODULE,
1903 .hooknum = NF_INET_FORWARD,
1906 /* After packet filtering, change source only for VS/NAT */
1908 .hook = ip_vs_reply6,
1909 .owner = THIS_MODULE,
1911 .hooknum = NF_INET_FORWARD,
1917 * Initialize IP Virtual Server netns mem.
1919 static int __net_init __ip_vs_init(struct net *net)
1921 struct netns_ipvs *ipvs;
1923 ipvs = net_generic(net, ip_vs_net_id);
1927 /* Hold the beast until a service is registerd */
1930 /* Counters used for creating unique names */
1931 ipvs->gen = atomic_read(&ipvs_netns_cnt);
1932 atomic_inc(&ipvs_netns_cnt);
1935 if (ip_vs_estimator_net_init(net) < 0)
1936 goto estimator_fail;
1938 if (ip_vs_control_net_init(net) < 0)
1941 if (ip_vs_protocol_net_init(net) < 0)
1944 if (ip_vs_app_net_init(net) < 0)
1947 if (ip_vs_conn_net_init(net) < 0)
1950 if (ip_vs_sync_net_init(net) < 0)
1953 printk(KERN_INFO "IPVS: Creating netns size=%zu id=%d\n",
1954 sizeof(struct netns_ipvs), ipvs->gen);
1961 ip_vs_conn_net_cleanup(net);
1963 ip_vs_app_net_cleanup(net);
1965 ip_vs_protocol_net_cleanup(net);
1967 ip_vs_control_net_cleanup(net);
1969 ip_vs_estimator_net_cleanup(net);
1975 static void __net_exit __ip_vs_cleanup(struct net *net)
1977 ip_vs_service_net_cleanup(net); /* ip_vs_flush() with locks */
1978 ip_vs_conn_net_cleanup(net);
1979 ip_vs_app_net_cleanup(net);
1980 ip_vs_protocol_net_cleanup(net);
1981 ip_vs_control_net_cleanup(net);
1982 ip_vs_estimator_net_cleanup(net);
1983 IP_VS_DBG(2, "ipvs netns %d released\n", net_ipvs(net)->gen);
1987 static void __net_exit __ip_vs_dev_cleanup(struct net *net)
1990 net_ipvs(net)->enable = 0; /* Disable packet reception */
1992 ip_vs_sync_net_cleanup(net);
1996 static struct pernet_operations ipvs_core_ops = {
1997 .init = __ip_vs_init,
1998 .exit = __ip_vs_cleanup,
1999 .id = &ip_vs_net_id,
2000 .size = sizeof(struct netns_ipvs),
2003 static struct pernet_operations ipvs_core_dev_ops = {
2004 .exit = __ip_vs_dev_cleanup,
2008 * Initialize IP Virtual Server
2010 static int __init ip_vs_init(void)
2014 ret = ip_vs_control_init();
2016 pr_err("can't setup control.\n");
2020 ip_vs_protocol_init();
2022 ret = ip_vs_conn_init();
2024 pr_err("can't setup connection table.\n");
2025 goto cleanup_protocol;
2028 ret = register_pernet_subsys(&ipvs_core_ops); /* Alloc ip_vs struct */
2032 ret = register_pernet_device(&ipvs_core_dev_ops);
2036 ret = nf_register_hooks(ip_vs_ops, ARRAY_SIZE(ip_vs_ops));
2038 pr_err("can't register hooks.\n");
2042 ret = ip_vs_register_nl_ioctl();
2044 pr_err("can't register netlink/ioctl.\n");
2048 pr_info("ipvs loaded.\n");
2053 nf_unregister_hooks(ip_vs_ops, ARRAY_SIZE(ip_vs_ops));
2055 unregister_pernet_device(&ipvs_core_dev_ops);
2057 unregister_pernet_subsys(&ipvs_core_ops);
2059 ip_vs_conn_cleanup();
2061 ip_vs_protocol_cleanup();
2062 ip_vs_control_cleanup();
2067 static void __exit ip_vs_cleanup(void)
2069 ip_vs_unregister_nl_ioctl();
2070 nf_unregister_hooks(ip_vs_ops, ARRAY_SIZE(ip_vs_ops));
2071 unregister_pernet_device(&ipvs_core_dev_ops);
2072 unregister_pernet_subsys(&ipvs_core_ops); /* free ip_vs struct */
2073 ip_vs_conn_cleanup();
2074 ip_vs_protocol_cleanup();
2075 ip_vs_control_cleanup();
2076 pr_info("ipvs unloaded.\n");
2079 module_init(ip_vs_init);
2080 module_exit(ip_vs_cleanup);
2081 MODULE_LICENSE("GPL");