/net/netfilter/ipvs/ip_vs_core.c
C | 2534 lines | 1761 code | 346 blank | 427 comment | 415 complexity | 74680fb4a34037458ed51e88a81ee483 MD5 | raw file
Possible License(s): AGPL-1.0, GPL-2.0, LGPL-2.0
- // SPDX-License-Identifier: GPL-2.0-or-later
- /*
- * IPVS An implementation of the IP virtual server support for the
- * LINUX operating system. IPVS is now implemented as a module
- * over the Netfilter framework. IPVS can be used to build a
- * high-performance and highly available server based on a
- * cluster of servers.
- *
- * Authors: Wensong Zhang <wensong@linuxvirtualserver.org>
- * Peter Kese <peter.kese@ijs.si>
- * Julian Anastasov <ja@ssi.bg>
- *
- * The IPVS code for kernel 2.2 was done by Wensong Zhang and Peter Kese,
- * with changes/fixes from Julian Anastasov, Lars Marowsky-Bree, Horms
- * and others.
- *
- * Changes:
- * Paul `Rusty' Russell properly handle non-linear skbs
- * Harald Welte don't use nfcache
- */
- #define KMSG_COMPONENT "IPVS"
- #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
- #include <linux/module.h>
- #include <linux/kernel.h>
- #include <linux/ip.h>
- #include <linux/tcp.h>
- #include <linux/sctp.h>
- #include <linux/icmp.h>
- #include <linux/slab.h>
- #include <net/ip.h>
- #include <net/tcp.h>
- #include <net/udp.h>
- #include <net/icmp.h> /* for icmp_send */
- #include <net/gue.h>
- #include <net/gre.h>
- #include <net/route.h>
- #include <net/ip6_checksum.h>
- #include <net/netns/generic.h> /* net_generic() */
- #include <linux/netfilter.h>
- #include <linux/netfilter_ipv4.h>
- #ifdef CONFIG_IP_VS_IPV6
- #include <net/ipv6.h>
- #include <linux/netfilter_ipv6.h>
- #include <net/ip6_route.h>
- #endif
- #include <net/ip_vs.h>
- #include <linux/indirect_call_wrapper.h>
- EXPORT_SYMBOL(register_ip_vs_scheduler);
- EXPORT_SYMBOL(unregister_ip_vs_scheduler);
- EXPORT_SYMBOL(ip_vs_proto_name);
- EXPORT_SYMBOL(ip_vs_conn_new);
- EXPORT_SYMBOL(ip_vs_conn_in_get);
- EXPORT_SYMBOL(ip_vs_conn_out_get);
- #ifdef CONFIG_IP_VS_PROTO_TCP
- EXPORT_SYMBOL(ip_vs_tcp_conn_listen);
- #endif
- EXPORT_SYMBOL(ip_vs_conn_put);
- #ifdef CONFIG_IP_VS_DEBUG
- EXPORT_SYMBOL(ip_vs_get_debug_level);
- #endif
- EXPORT_SYMBOL(ip_vs_new_conn_out);
- #ifdef CONFIG_IP_VS_PROTO_TCP
- INDIRECT_CALLABLE_DECLARE(int
- tcp_snat_handler(struct sk_buff *skb, struct ip_vs_protocol *pp,
- struct ip_vs_conn *cp, struct ip_vs_iphdr *iph));
- #endif
- #ifdef CONFIG_IP_VS_PROTO_UDP
- INDIRECT_CALLABLE_DECLARE(int
- udp_snat_handler(struct sk_buff *skb, struct ip_vs_protocol *pp,
- struct ip_vs_conn *cp, struct ip_vs_iphdr *iph));
- #endif
- #if defined(CONFIG_IP_VS_PROTO_TCP) && defined(CONFIG_IP_VS_PROTO_UDP)
- #define SNAT_CALL(f, ...) \
- INDIRECT_CALL_2(f, tcp_snat_handler, udp_snat_handler, __VA_ARGS__)
- #elif defined(CONFIG_IP_VS_PROTO_TCP)
- #define SNAT_CALL(f, ...) INDIRECT_CALL_1(f, tcp_snat_handler, __VA_ARGS__)
- #elif defined(CONFIG_IP_VS_PROTO_UDP)
- #define SNAT_CALL(f, ...) INDIRECT_CALL_1(f, udp_snat_handler, __VA_ARGS__)
- #else
- #define SNAT_CALL(f, ...) f(__VA_ARGS__)
- #endif
- static unsigned int ip_vs_net_id __read_mostly;
- /* netns cnt used for uniqueness */
- static atomic_t ipvs_netns_cnt = ATOMIC_INIT(0);
- /* ID used in ICMP lookups */
- #define icmp_id(icmph) (((icmph)->un).echo.id)
- #define icmpv6_id(icmph) (icmph->icmp6_dataun.u_echo.identifier)
- const char *ip_vs_proto_name(unsigned int proto)
- {
- static char buf[20];
- switch (proto) {
- case IPPROTO_IP:
- return "IP";
- case IPPROTO_UDP:
- return "UDP";
- case IPPROTO_TCP:
- return "TCP";
- case IPPROTO_SCTP:
- return "SCTP";
- case IPPROTO_ICMP:
- return "ICMP";
- #ifdef CONFIG_IP_VS_IPV6
- case IPPROTO_ICMPV6:
- return "ICMPv6";
- #endif
- default:
- sprintf(buf, "IP_%u", proto);
- return buf;
- }
- }
- void ip_vs_init_hash_table(struct list_head *table, int rows)
- {
- while (--rows >= 0)
- INIT_LIST_HEAD(&table[rows]);
- }
- static inline void
- ip_vs_in_stats(struct ip_vs_conn *cp, struct sk_buff *skb)
- {
- struct ip_vs_dest *dest = cp->dest;
- struct netns_ipvs *ipvs = cp->ipvs;
- if (dest && (dest->flags & IP_VS_DEST_F_AVAILABLE)) {
- struct ip_vs_cpu_stats *s;
- struct ip_vs_service *svc;
- local_bh_disable();
- s = this_cpu_ptr(dest->stats.cpustats);
- u64_stats_update_begin(&s->syncp);
- s->cnt.inpkts++;
- s->cnt.inbytes += skb->len;
- u64_stats_update_end(&s->syncp);
- svc = rcu_dereference(dest->svc);
- s = this_cpu_ptr(svc->stats.cpustats);
- u64_stats_update_begin(&s->syncp);
- s->cnt.inpkts++;
- s->cnt.inbytes += skb->len;
- u64_stats_update_end(&s->syncp);
- s = this_cpu_ptr(ipvs->tot_stats.cpustats);
- u64_stats_update_begin(&s->syncp);
- s->cnt.inpkts++;
- s->cnt.inbytes += skb->len;
- u64_stats_update_end(&s->syncp);
- local_bh_enable();
- }
- }
- static inline void
- ip_vs_out_stats(struct ip_vs_conn *cp, struct sk_buff *skb)
- {
- struct ip_vs_dest *dest = cp->dest;
- struct netns_ipvs *ipvs = cp->ipvs;
- if (dest && (dest->flags & IP_VS_DEST_F_AVAILABLE)) {
- struct ip_vs_cpu_stats *s;
- struct ip_vs_service *svc;
- local_bh_disable();
- s = this_cpu_ptr(dest->stats.cpustats);
- u64_stats_update_begin(&s->syncp);
- s->cnt.outpkts++;
- s->cnt.outbytes += skb->len;
- u64_stats_update_end(&s->syncp);
- svc = rcu_dereference(dest->svc);
- s = this_cpu_ptr(svc->stats.cpustats);
- u64_stats_update_begin(&s->syncp);
- s->cnt.outpkts++;
- s->cnt.outbytes += skb->len;
- u64_stats_update_end(&s->syncp);
- s = this_cpu_ptr(ipvs->tot_stats.cpustats);
- u64_stats_update_begin(&s->syncp);
- s->cnt.outpkts++;
- s->cnt.outbytes += skb->len;
- u64_stats_update_end(&s->syncp);
- local_bh_enable();
- }
- }
- static inline void
- ip_vs_conn_stats(struct ip_vs_conn *cp, struct ip_vs_service *svc)
- {
- struct netns_ipvs *ipvs = svc->ipvs;
- struct ip_vs_cpu_stats *s;
- local_bh_disable();
- s = this_cpu_ptr(cp->dest->stats.cpustats);
- u64_stats_update_begin(&s->syncp);
- s->cnt.conns++;
- u64_stats_update_end(&s->syncp);
- s = this_cpu_ptr(svc->stats.cpustats);
- u64_stats_update_begin(&s->syncp);
- s->cnt.conns++;
- u64_stats_update_end(&s->syncp);
- s = this_cpu_ptr(ipvs->tot_stats.cpustats);
- u64_stats_update_begin(&s->syncp);
- s->cnt.conns++;
- u64_stats_update_end(&s->syncp);
- local_bh_enable();
- }
- static inline void
- ip_vs_set_state(struct ip_vs_conn *cp, int direction,
- const struct sk_buff *skb,
- struct ip_vs_proto_data *pd)
- {
- if (likely(pd->pp->state_transition))
- pd->pp->state_transition(cp, direction, skb, pd);
- }
- static inline int
- ip_vs_conn_fill_param_persist(const struct ip_vs_service *svc,
- struct sk_buff *skb, int protocol,
- const union nf_inet_addr *caddr, __be16 cport,
- const union nf_inet_addr *vaddr, __be16 vport,
- struct ip_vs_conn_param *p)
- {
- ip_vs_conn_fill_param(svc->ipvs, svc->af, protocol, caddr, cport, vaddr,
- vport, p);
- p->pe = rcu_dereference(svc->pe);
- if (p->pe && p->pe->fill_param)
- return p->pe->fill_param(p, skb);
- return 0;
- }
- /*
- * IPVS persistent scheduling function
- * It creates a connection entry according to its template if exists,
- * or selects a server and creates a connection entry plus a template.
- * Locking: we are svc user (svc->refcnt), so we hold all dests too
- * Protocols supported: TCP, UDP
- */
- static struct ip_vs_conn *
- ip_vs_sched_persist(struct ip_vs_service *svc,
- struct sk_buff *skb, __be16 src_port, __be16 dst_port,
- int *ignored, struct ip_vs_iphdr *iph)
- {
- struct ip_vs_conn *cp = NULL;
- struct ip_vs_dest *dest;
- struct ip_vs_conn *ct;
- __be16 dport = 0; /* destination port to forward */
- unsigned int flags;
- struct ip_vs_conn_param param;
- const union nf_inet_addr fwmark = { .ip = htonl(svc->fwmark) };
- union nf_inet_addr snet; /* source network of the client,
- after masking */
- const union nf_inet_addr *src_addr, *dst_addr;
- if (likely(!ip_vs_iph_inverse(iph))) {
- src_addr = &iph->saddr;
- dst_addr = &iph->daddr;
- } else {
- src_addr = &iph->daddr;
- dst_addr = &iph->saddr;
- }
- /* Mask saddr with the netmask to adjust template granularity */
- #ifdef CONFIG_IP_VS_IPV6
- if (svc->af == AF_INET6)
- ipv6_addr_prefix(&snet.in6, &src_addr->in6,
- (__force __u32) svc->netmask);
- else
- #endif
- snet.ip = src_addr->ip & svc->netmask;
- IP_VS_DBG_BUF(6, "p-schedule: src %s:%u dest %s:%u "
- "mnet %s\n",
- IP_VS_DBG_ADDR(svc->af, src_addr), ntohs(src_port),
- IP_VS_DBG_ADDR(svc->af, dst_addr), ntohs(dst_port),
- IP_VS_DBG_ADDR(svc->af, &snet));
- /*
- * As far as we know, FTP is a very complicated network protocol, and
- * it uses control connection and data connections. For active FTP,
- * FTP server initialize data connection to the client, its source port
- * is often 20. For passive FTP, FTP server tells the clients the port
- * that it passively listens to, and the client issues the data
- * connection. In the tunneling or direct routing mode, the load
- * balancer is on the client-to-server half of connection, the port
- * number is unknown to the load balancer. So, a conn template like
- * <caddr, 0, vaddr, 0, daddr, 0> is created for persistent FTP
- * service, and a template like <caddr, 0, vaddr, vport, daddr, dport>
- * is created for other persistent services.
- */
- {
- int protocol = iph->protocol;
- const union nf_inet_addr *vaddr = dst_addr;
- __be16 vport = 0;
- if (dst_port == svc->port) {
- /* non-FTP template:
- * <protocol, caddr, 0, vaddr, vport, daddr, dport>
- * FTP template:
- * <protocol, caddr, 0, vaddr, 0, daddr, 0>
- */
- if (svc->port != FTPPORT)
- vport = dst_port;
- } else {
- /* Note: persistent fwmark-based services and
- * persistent port zero service are handled here.
- * fwmark template:
- * <IPPROTO_IP,caddr,0,fwmark,0,daddr,0>
- * port zero template:
- * <protocol,caddr,0,vaddr,0,daddr,0>
- */
- if (svc->fwmark) {
- protocol = IPPROTO_IP;
- vaddr = &fwmark;
- }
- }
- /* return *ignored = -1 so NF_DROP can be used */
- if (ip_vs_conn_fill_param_persist(svc, skb, protocol, &snet, 0,
- vaddr, vport, ¶m) < 0) {
- *ignored = -1;
- return NULL;
- }
- }
- /* Check if a template already exists */
- ct = ip_vs_ct_in_get(¶m);
- if (!ct || !ip_vs_check_template(ct, NULL)) {
- struct ip_vs_scheduler *sched;
- /*
- * No template found or the dest of the connection
- * template is not available.
- * return *ignored=0 i.e. ICMP and NF_DROP
- */
- sched = rcu_dereference(svc->scheduler);
- if (sched) {
- /* read svc->sched_data after svc->scheduler */
- smp_rmb();
- dest = sched->schedule(svc, skb, iph);
- } else {
- dest = NULL;
- }
- if (!dest) {
- IP_VS_DBG(1, "p-schedule: no dest found.\n");
- kfree(param.pe_data);
- *ignored = 0;
- return NULL;
- }
- if (dst_port == svc->port && svc->port != FTPPORT)
- dport = dest->port;
- /* Create a template
- * This adds param.pe_data to the template,
- * and thus param.pe_data will be destroyed
- * when the template expires */
- ct = ip_vs_conn_new(¶m, dest->af, &dest->addr, dport,
- IP_VS_CONN_F_TEMPLATE, dest, skb->mark);
- if (ct == NULL) {
- kfree(param.pe_data);
- *ignored = -1;
- return NULL;
- }
- ct->timeout = svc->timeout;
- } else {
- /* set destination with the found template */
- dest = ct->dest;
- kfree(param.pe_data);
- }
- dport = dst_port;
- if (dport == svc->port && dest->port)
- dport = dest->port;
- flags = (svc->flags & IP_VS_SVC_F_ONEPACKET
- && iph->protocol == IPPROTO_UDP) ?
- IP_VS_CONN_F_ONE_PACKET : 0;
- /*
- * Create a new connection according to the template
- */
- ip_vs_conn_fill_param(svc->ipvs, svc->af, iph->protocol, src_addr,
- src_port, dst_addr, dst_port, ¶m);
- cp = ip_vs_conn_new(¶m, dest->af, &dest->addr, dport, flags, dest,
- skb->mark);
- if (cp == NULL) {
- ip_vs_conn_put(ct);
- *ignored = -1;
- return NULL;
- }
- /*
- * Add its control
- */
- ip_vs_control_add(cp, ct);
- ip_vs_conn_put(ct);
- ip_vs_conn_stats(cp, svc);
- return cp;
- }
- /*
- * IPVS main scheduling function
- * It selects a server according to the virtual service, and
- * creates a connection entry.
- * Protocols supported: TCP, UDP
- *
- * Usage of *ignored
- *
- * 1 : protocol tried to schedule (eg. on SYN), found svc but the
- * svc/scheduler decides that this packet should be accepted with
- * NF_ACCEPT because it must not be scheduled.
- *
- * 0 : scheduler can not find destination, so try bypass or
- * return ICMP and then NF_DROP (ip_vs_leave).
- *
- * -1 : scheduler tried to schedule but fatal error occurred, eg.
- * ip_vs_conn_new failure (ENOMEM) or ip_vs_sip_fill_param
- * failure such as missing Call-ID, ENOMEM on skb_linearize
- * or pe_data. In this case we should return NF_DROP without
- * any attempts to send ICMP with ip_vs_leave.
- */
- struct ip_vs_conn *
- ip_vs_schedule(struct ip_vs_service *svc, struct sk_buff *skb,
- struct ip_vs_proto_data *pd, int *ignored,
- struct ip_vs_iphdr *iph)
- {
- struct ip_vs_protocol *pp = pd->pp;
- struct ip_vs_conn *cp = NULL;
- struct ip_vs_scheduler *sched;
- struct ip_vs_dest *dest;
- __be16 _ports[2], *pptr, cport, vport;
- const void *caddr, *vaddr;
- unsigned int flags;
- *ignored = 1;
- /*
- * IPv6 frags, only the first hit here.
- */
- pptr = frag_safe_skb_hp(skb, iph->len, sizeof(_ports), _ports);
- if (pptr == NULL)
- return NULL;
- if (likely(!ip_vs_iph_inverse(iph))) {
- cport = pptr[0];
- caddr = &iph->saddr;
- vport = pptr[1];
- vaddr = &iph->daddr;
- } else {
- cport = pptr[1];
- caddr = &iph->daddr;
- vport = pptr[0];
- vaddr = &iph->saddr;
- }
- /*
- * FTPDATA needs this check when using local real server.
- * Never schedule Active FTPDATA connections from real server.
- * For LVS-NAT they must be already created. For other methods
- * with persistence the connection is created on SYN+ACK.
- */
- if (cport == FTPDATA) {
- IP_VS_DBG_PKT(12, svc->af, pp, skb, iph->off,
- "Not scheduling FTPDATA");
- return NULL;
- }
- /*
- * Do not schedule replies from local real server.
- */
- if ((!skb->dev || skb->dev->flags & IFF_LOOPBACK)) {
- iph->hdr_flags ^= IP_VS_HDR_INVERSE;
- cp = INDIRECT_CALL_1(pp->conn_in_get,
- ip_vs_conn_in_get_proto, svc->ipvs,
- svc->af, skb, iph);
- iph->hdr_flags ^= IP_VS_HDR_INVERSE;
- if (cp) {
- IP_VS_DBG_PKT(12, svc->af, pp, skb, iph->off,
- "Not scheduling reply for existing"
- " connection");
- __ip_vs_conn_put(cp);
- return NULL;
- }
- }
- /*
- * Persistent service
- */
- if (svc->flags & IP_VS_SVC_F_PERSISTENT)
- return ip_vs_sched_persist(svc, skb, cport, vport, ignored,
- iph);
- *ignored = 0;
- /*
- * Non-persistent service
- */
- if (!svc->fwmark && vport != svc->port) {
- if (!svc->port)
- pr_err("Schedule: port zero only supported "
- "in persistent services, "
- "check your ipvs configuration\n");
- return NULL;
- }
- sched = rcu_dereference(svc->scheduler);
- if (sched) {
- /* read svc->sched_data after svc->scheduler */
- smp_rmb();
- dest = sched->schedule(svc, skb, iph);
- } else {
- dest = NULL;
- }
- if (dest == NULL) {
- IP_VS_DBG(1, "Schedule: no dest found.\n");
- return NULL;
- }
- flags = (svc->flags & IP_VS_SVC_F_ONEPACKET
- && iph->protocol == IPPROTO_UDP) ?
- IP_VS_CONN_F_ONE_PACKET : 0;
- /*
- * Create a connection entry.
- */
- {
- struct ip_vs_conn_param p;
- ip_vs_conn_fill_param(svc->ipvs, svc->af, iph->protocol,
- caddr, cport, vaddr, vport, &p);
- cp = ip_vs_conn_new(&p, dest->af, &dest->addr,
- dest->port ? dest->port : vport,
- flags, dest, skb->mark);
- if (!cp) {
- *ignored = -1;
- return NULL;
- }
- }
- IP_VS_DBG_BUF(6, "Schedule fwd:%c c:%s:%u v:%s:%u "
- "d:%s:%u conn->flags:%X conn->refcnt:%d\n",
- ip_vs_fwd_tag(cp),
- IP_VS_DBG_ADDR(cp->af, &cp->caddr), ntohs(cp->cport),
- IP_VS_DBG_ADDR(cp->af, &cp->vaddr), ntohs(cp->vport),
- IP_VS_DBG_ADDR(cp->daf, &cp->daddr), ntohs(cp->dport),
- cp->flags, refcount_read(&cp->refcnt));
- ip_vs_conn_stats(cp, svc);
- return cp;
- }
- static inline int ip_vs_addr_is_unicast(struct net *net, int af,
- union nf_inet_addr *addr)
- {
- #ifdef CONFIG_IP_VS_IPV6
- if (af == AF_INET6)
- return ipv6_addr_type(&addr->in6) & IPV6_ADDR_UNICAST;
- #endif
- return (inet_addr_type(net, addr->ip) == RTN_UNICAST);
- }
- /*
- * Pass or drop the packet.
- * Called by ip_vs_in, when the virtual service is available but
- * no destination is available for a new connection.
- */
- int ip_vs_leave(struct ip_vs_service *svc, struct sk_buff *skb,
- struct ip_vs_proto_data *pd, struct ip_vs_iphdr *iph)
- {
- __be16 _ports[2], *pptr, dport;
- struct netns_ipvs *ipvs = svc->ipvs;
- struct net *net = ipvs->net;
- pptr = frag_safe_skb_hp(skb, iph->len, sizeof(_ports), _ports);
- if (!pptr)
- return NF_DROP;
- dport = likely(!ip_vs_iph_inverse(iph)) ? pptr[1] : pptr[0];
- /* if it is fwmark-based service, the cache_bypass sysctl is up
- and the destination is a non-local unicast, then create
- a cache_bypass connection entry */
- if (sysctl_cache_bypass(ipvs) && svc->fwmark &&
- !(iph->hdr_flags & (IP_VS_HDR_INVERSE | IP_VS_HDR_ICMP)) &&
- ip_vs_addr_is_unicast(net, svc->af, &iph->daddr)) {
- int ret;
- struct ip_vs_conn *cp;
- unsigned int flags = (svc->flags & IP_VS_SVC_F_ONEPACKET &&
- iph->protocol == IPPROTO_UDP) ?
- IP_VS_CONN_F_ONE_PACKET : 0;
- union nf_inet_addr daddr = { .all = { 0, 0, 0, 0 } };
- /* create a new connection entry */
- IP_VS_DBG(6, "%s(): create a cache_bypass entry\n", __func__);
- {
- struct ip_vs_conn_param p;
- ip_vs_conn_fill_param(svc->ipvs, svc->af, iph->protocol,
- &iph->saddr, pptr[0],
- &iph->daddr, pptr[1], &p);
- cp = ip_vs_conn_new(&p, svc->af, &daddr, 0,
- IP_VS_CONN_F_BYPASS | flags,
- NULL, skb->mark);
- if (!cp)
- return NF_DROP;
- }
- /* statistics */
- ip_vs_in_stats(cp, skb);
- /* set state */
- ip_vs_set_state(cp, IP_VS_DIR_INPUT, skb, pd);
- /* transmit the first SYN packet */
- ret = cp->packet_xmit(skb, cp, pd->pp, iph);
- /* do not touch skb anymore */
- if ((cp->flags & IP_VS_CONN_F_ONE_PACKET) && cp->control)
- atomic_inc(&cp->control->in_pkts);
- else
- atomic_inc(&cp->in_pkts);
- ip_vs_conn_put(cp);
- return ret;
- }
- /*
- * When the virtual ftp service is presented, packets destined
- * for other services on the VIP may get here (except services
- * listed in the ipvs table), pass the packets, because it is
- * not ipvs job to decide to drop the packets.
- */
- if (svc->port == FTPPORT && dport != FTPPORT)
- return NF_ACCEPT;
- if (unlikely(ip_vs_iph_icmp(iph)))
- return NF_DROP;
- /*
- * Notify the client that the destination is unreachable, and
- * release the socket buffer.
- * Since it is in IP layer, the TCP socket is not actually
- * created, the TCP RST packet cannot be sent, instead that
- * ICMP_PORT_UNREACH is sent here no matter it is TCP/UDP. --WZ
- */
- #ifdef CONFIG_IP_VS_IPV6
- if (svc->af == AF_INET6) {
- if (!skb->dev)
- skb->dev = net->loopback_dev;
- icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
- } else
- #endif
- icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
- return NF_DROP;
- }
- #ifdef CONFIG_SYSCTL
- static int sysctl_snat_reroute(struct netns_ipvs *ipvs)
- {
- return ipvs->sysctl_snat_reroute;
- }
- static int sysctl_nat_icmp_send(struct netns_ipvs *ipvs)
- {
- return ipvs->sysctl_nat_icmp_send;
- }
- static int sysctl_expire_nodest_conn(struct netns_ipvs *ipvs)
- {
- return ipvs->sysctl_expire_nodest_conn;
- }
- #else
- static int sysctl_snat_reroute(struct netns_ipvs *ipvs) { return 0; }
- static int sysctl_nat_icmp_send(struct netns_ipvs *ipvs) { return 0; }
- static int sysctl_expire_nodest_conn(struct netns_ipvs *ipvs) { return 0; }
- #endif
- __sum16 ip_vs_checksum_complete(struct sk_buff *skb, int offset)
- {
- return csum_fold(skb_checksum(skb, offset, skb->len - offset, 0));
- }
- static inline enum ip_defrag_users ip_vs_defrag_user(unsigned int hooknum)
- {
- if (NF_INET_LOCAL_IN == hooknum)
- return IP_DEFRAG_VS_IN;
- if (NF_INET_FORWARD == hooknum)
- return IP_DEFRAG_VS_FWD;
- return IP_DEFRAG_VS_OUT;
- }
- static inline int ip_vs_gather_frags(struct netns_ipvs *ipvs,
- struct sk_buff *skb, u_int32_t user)
- {
- int err;
- local_bh_disable();
- err = ip_defrag(ipvs->net, skb, user);
- local_bh_enable();
- if (!err)
- ip_send_check(ip_hdr(skb));
- return err;
- }
- static int ip_vs_route_me_harder(struct netns_ipvs *ipvs, int af,
- struct sk_buff *skb, unsigned int hooknum)
- {
- if (!sysctl_snat_reroute(ipvs))
- return 0;
- /* Reroute replies only to remote clients (FORWARD and LOCAL_OUT) */
- if (NF_INET_LOCAL_IN == hooknum)
- return 0;
- #ifdef CONFIG_IP_VS_IPV6
- if (af == AF_INET6) {
- struct dst_entry *dst = skb_dst(skb);
- if (dst->dev && !(dst->dev->flags & IFF_LOOPBACK) &&
- ip6_route_me_harder(ipvs->net, skb) != 0)
- return 1;
- } else
- #endif
- if (!(skb_rtable(skb)->rt_flags & RTCF_LOCAL) &&
- ip_route_me_harder(ipvs->net, skb, RTN_LOCAL) != 0)
- return 1;
- return 0;
- }
- /*
- * Packet has been made sufficiently writable in caller
- * - inout: 1=in->out, 0=out->in
- */
- void ip_vs_nat_icmp(struct sk_buff *skb, struct ip_vs_protocol *pp,
- struct ip_vs_conn *cp, int inout)
- {
- struct iphdr *iph = ip_hdr(skb);
- unsigned int icmp_offset = iph->ihl*4;
- struct icmphdr *icmph = (struct icmphdr *)(skb_network_header(skb) +
- icmp_offset);
- struct iphdr *ciph = (struct iphdr *)(icmph + 1);
- if (inout) {
- iph->saddr = cp->vaddr.ip;
- ip_send_check(iph);
- ciph->daddr = cp->vaddr.ip;
- ip_send_check(ciph);
- } else {
- iph->daddr = cp->daddr.ip;
- ip_send_check(iph);
- ciph->saddr = cp->daddr.ip;
- ip_send_check(ciph);
- }
- /* the TCP/UDP/SCTP port */
- if (IPPROTO_TCP == ciph->protocol || IPPROTO_UDP == ciph->protocol ||
- IPPROTO_SCTP == ciph->protocol) {
- __be16 *ports = (void *)ciph + ciph->ihl*4;
- if (inout)
- ports[1] = cp->vport;
- else
- ports[0] = cp->dport;
- }
- /* And finally the ICMP checksum */
- icmph->checksum = 0;
- icmph->checksum = ip_vs_checksum_complete(skb, icmp_offset);
- skb->ip_summed = CHECKSUM_UNNECESSARY;
- if (inout)
- IP_VS_DBG_PKT(11, AF_INET, pp, skb, (void *)ciph - (void *)iph,
- "Forwarding altered outgoing ICMP");
- else
- IP_VS_DBG_PKT(11, AF_INET, pp, skb, (void *)ciph - (void *)iph,
- "Forwarding altered incoming ICMP");
- }
- #ifdef CONFIG_IP_VS_IPV6
- void ip_vs_nat_icmp_v6(struct sk_buff *skb, struct ip_vs_protocol *pp,
- struct ip_vs_conn *cp, int inout)
- {
- struct ipv6hdr *iph = ipv6_hdr(skb);
- unsigned int icmp_offset = 0;
- unsigned int offs = 0; /* header offset*/
- int protocol;
- struct icmp6hdr *icmph;
- struct ipv6hdr *ciph;
- unsigned short fragoffs;
- ipv6_find_hdr(skb, &icmp_offset, IPPROTO_ICMPV6, &fragoffs, NULL);
- icmph = (struct icmp6hdr *)(skb_network_header(skb) + icmp_offset);
- offs = icmp_offset + sizeof(struct icmp6hdr);
- ciph = (struct ipv6hdr *)(skb_network_header(skb) + offs);
- protocol = ipv6_find_hdr(skb, &offs, -1, &fragoffs, NULL);
- if (inout) {
- iph->saddr = cp->vaddr.in6;
- ciph->daddr = cp->vaddr.in6;
- } else {
- iph->daddr = cp->daddr.in6;
- ciph->saddr = cp->daddr.in6;
- }
- /* the TCP/UDP/SCTP port */
- if (!fragoffs && (IPPROTO_TCP == protocol || IPPROTO_UDP == protocol ||
- IPPROTO_SCTP == protocol)) {
- __be16 *ports = (void *)(skb_network_header(skb) + offs);
- IP_VS_DBG(11, "%s() changed port %d to %d\n", __func__,
- ntohs(inout ? ports[1] : ports[0]),
- ntohs(inout ? cp->vport : cp->dport));
- if (inout)
- ports[1] = cp->vport;
- else
- ports[0] = cp->dport;
- }
- /* And finally the ICMP checksum */
- icmph->icmp6_cksum = ~csum_ipv6_magic(&iph->saddr, &iph->daddr,
- skb->len - icmp_offset,
- IPPROTO_ICMPV6, 0);
- skb->csum_start = skb_network_header(skb) - skb->head + icmp_offset;
- skb->csum_offset = offsetof(struct icmp6hdr, icmp6_cksum);
- skb->ip_summed = CHECKSUM_PARTIAL;
- if (inout)
- IP_VS_DBG_PKT(11, AF_INET6, pp, skb,
- (void *)ciph - (void *)iph,
- "Forwarding altered outgoing ICMPv6");
- else
- IP_VS_DBG_PKT(11, AF_INET6, pp, skb,
- (void *)ciph - (void *)iph,
- "Forwarding altered incoming ICMPv6");
- }
- #endif
- /* Handle relevant response ICMP messages - forward to the right
- * destination host.
- */
- static int handle_response_icmp(int af, struct sk_buff *skb,
- union nf_inet_addr *snet,
- __u8 protocol, struct ip_vs_conn *cp,
- struct ip_vs_protocol *pp,
- unsigned int offset, unsigned int ihl,
- unsigned int hooknum)
- {
- unsigned int verdict = NF_DROP;
- if (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ)
- goto ignore_cp;
- /* Ensure the checksum is correct */
- if (!skb_csum_unnecessary(skb) && ip_vs_checksum_complete(skb, ihl)) {
- /* Failed checksum! */
- IP_VS_DBG_BUF(1, "Forward ICMP: failed checksum from %s!\n",
- IP_VS_DBG_ADDR(af, snet));
- goto out;
- }
- if (IPPROTO_TCP == protocol || IPPROTO_UDP == protocol ||
- IPPROTO_SCTP == protocol)
- offset += 2 * sizeof(__u16);
- if (skb_ensure_writable(skb, offset))
- goto out;
- #ifdef CONFIG_IP_VS_IPV6
- if (af == AF_INET6)
- ip_vs_nat_icmp_v6(skb, pp, cp, 1);
- else
- #endif
- ip_vs_nat_icmp(skb, pp, cp, 1);
- if (ip_vs_route_me_harder(cp->ipvs, af, skb, hooknum))
- goto out;
- /* do the statistics and put it back */
- ip_vs_out_stats(cp, skb);
- skb->ipvs_property = 1;
- if (!(cp->flags & IP_VS_CONN_F_NFCT))
- ip_vs_notrack(skb);
- else
- ip_vs_update_conntrack(skb, cp, 0);
- ignore_cp:
- verdict = NF_ACCEPT;
- out:
- __ip_vs_conn_put(cp);
- return verdict;
- }
- /*
- * Handle ICMP messages in the inside-to-outside direction (outgoing).
- * Find any that might be relevant, check against existing connections.
- * Currently handles error types - unreachable, quench, ttl exceeded.
- */
- static int ip_vs_out_icmp(struct netns_ipvs *ipvs, struct sk_buff *skb,
- int *related, unsigned int hooknum)
- {
- struct iphdr *iph;
- struct icmphdr _icmph, *ic;
- struct iphdr _ciph, *cih; /* The ip header contained within the ICMP */
- struct ip_vs_iphdr ciph;
- struct ip_vs_conn *cp;
- struct ip_vs_protocol *pp;
- unsigned int offset, ihl;
- union nf_inet_addr snet;
- *related = 1;
- /* reassemble IP fragments */
- if (ip_is_fragment(ip_hdr(skb))) {
- if (ip_vs_gather_frags(ipvs, skb, ip_vs_defrag_user(hooknum)))
- return NF_STOLEN;
- }
- iph = ip_hdr(skb);
- offset = ihl = iph->ihl * 4;
- ic = skb_header_pointer(skb, offset, sizeof(_icmph), &_icmph);
- if (ic == NULL)
- return NF_DROP;
- IP_VS_DBG(12, "Outgoing ICMP (%d,%d) %pI4->%pI4\n",
- ic->type, ntohs(icmp_id(ic)),
- &iph->saddr, &iph->daddr);
- /*
- * Work through seeing if this is for us.
- * These checks are supposed to be in an order that means easy
- * things are checked first to speed up processing.... however
- * this means that some packets will manage to get a long way
- * down this stack and then be rejected, but that's life.
- */
- if ((ic->type != ICMP_DEST_UNREACH) &&
- (ic->type != ICMP_SOURCE_QUENCH) &&
- (ic->type != ICMP_TIME_EXCEEDED)) {
- *related = 0;
- return NF_ACCEPT;
- }
- /* Now find the contained IP header */
- offset += sizeof(_icmph);
- cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
- if (cih == NULL)
- return NF_ACCEPT; /* The packet looks wrong, ignore */
- pp = ip_vs_proto_get(cih->protocol);
- if (!pp)
- return NF_ACCEPT;
- /* Is the embedded protocol header present? */
- if (unlikely(cih->frag_off & htons(IP_OFFSET) &&
- pp->dont_defrag))
- return NF_ACCEPT;
- IP_VS_DBG_PKT(11, AF_INET, pp, skb, offset,
- "Checking outgoing ICMP for");
- ip_vs_fill_iph_skb_icmp(AF_INET, skb, offset, true, &ciph);
- /* The embedded headers contain source and dest in reverse order */
- cp = INDIRECT_CALL_1(pp->conn_out_get, ip_vs_conn_out_get_proto,
- ipvs, AF_INET, skb, &ciph);
- if (!cp)
- return NF_ACCEPT;
- snet.ip = iph->saddr;
- return handle_response_icmp(AF_INET, skb, &snet, cih->protocol, cp,
- pp, ciph.len, ihl, hooknum);
- }
- #ifdef CONFIG_IP_VS_IPV6
- static int ip_vs_out_icmp_v6(struct netns_ipvs *ipvs, struct sk_buff *skb,
- int *related, unsigned int hooknum,
- struct ip_vs_iphdr *ipvsh)
- {
- struct icmp6hdr _icmph, *ic;
- struct ip_vs_iphdr ciph = {.flags = 0, .fragoffs = 0};/*Contained IP */
- struct ip_vs_conn *cp;
- struct ip_vs_protocol *pp;
- union nf_inet_addr snet;
- unsigned int offset;
- *related = 1;
- ic = frag_safe_skb_hp(skb, ipvsh->len, sizeof(_icmph), &_icmph);
- if (ic == NULL)
- return NF_DROP;
- /*
- * Work through seeing if this is for us.
- * These checks are supposed to be in an order that means easy
- * things are checked first to speed up processing.... however
- * this means that some packets will manage to get a long way
- * down this stack and then be rejected, but that's life.
- */
- if (ic->icmp6_type & ICMPV6_INFOMSG_MASK) {
- *related = 0;
- return NF_ACCEPT;
- }
- /* Fragment header that is before ICMP header tells us that:
- * it's not an error message since they can't be fragmented.
- */
- if (ipvsh->flags & IP6_FH_F_FRAG)
- return NF_DROP;
- IP_VS_DBG(8, "Outgoing ICMPv6 (%d,%d) %pI6c->%pI6c\n",
- ic->icmp6_type, ntohs(icmpv6_id(ic)),
- &ipvsh->saddr, &ipvsh->daddr);
- if (!ip_vs_fill_iph_skb_icmp(AF_INET6, skb, ipvsh->len + sizeof(_icmph),
- true, &ciph))
- return NF_ACCEPT; /* The packet looks wrong, ignore */
- pp = ip_vs_proto_get(ciph.protocol);
- if (!pp)
- return NF_ACCEPT;
- /* The embedded headers contain source and dest in reverse order */
- cp = INDIRECT_CALL_1(pp->conn_out_get, ip_vs_conn_out_get_proto,
- ipvs, AF_INET6, skb, &ciph);
- if (!cp)
- return NF_ACCEPT;
- snet.in6 = ciph.saddr.in6;
- offset = ciph.len;
- return handle_response_icmp(AF_INET6, skb, &snet, ciph.protocol, cp,
- pp, offset, sizeof(struct ipv6hdr),
- hooknum);
- }
- #endif
- /*
- * Check if sctp chunc is ABORT chunk
- */
- static inline int is_sctp_abort(const struct sk_buff *skb, int nh_len)
- {
- struct sctp_chunkhdr *sch, schunk;
- sch = skb_header_pointer(skb, nh_len + sizeof(struct sctphdr),
- sizeof(schunk), &schunk);
- if (sch == NULL)
- return 0;
- if (sch->type == SCTP_CID_ABORT)
- return 1;
- return 0;
- }
- static inline int is_tcp_reset(const struct sk_buff *skb, int nh_len)
- {
- struct tcphdr _tcph, *th;
- th = skb_header_pointer(skb, nh_len, sizeof(_tcph), &_tcph);
- if (th == NULL)
- return 0;
- return th->rst;
- }
- static inline bool is_new_conn(const struct sk_buff *skb,
- struct ip_vs_iphdr *iph)
- {
- switch (iph->protocol) {
- case IPPROTO_TCP: {
- struct tcphdr _tcph, *th;
- th = skb_header_pointer(skb, iph->len, sizeof(_tcph), &_tcph);
- if (th == NULL)
- return false;
- return th->syn;
- }
- case IPPROTO_SCTP: {
- struct sctp_chunkhdr *sch, schunk;
- sch = skb_header_pointer(skb, iph->len + sizeof(struct sctphdr),
- sizeof(schunk), &schunk);
- if (sch == NULL)
- return false;
- return sch->type == SCTP_CID_INIT;
- }
- default:
- return false;
- }
- }
- static inline bool is_new_conn_expected(const struct ip_vs_conn *cp,
- int conn_reuse_mode)
- {
- /* Controlled (FTP DATA or persistence)? */
- if (cp->control)
- return false;
- switch (cp->protocol) {
- case IPPROTO_TCP:
- return (cp->state == IP_VS_TCP_S_TIME_WAIT) ||
- (cp->state == IP_VS_TCP_S_CLOSE) ||
- ((conn_reuse_mode & 2) &&
- (cp->state == IP_VS_TCP_S_FIN_WAIT) &&
- (cp->flags & IP_VS_CONN_F_NOOUTPUT));
- case IPPROTO_SCTP:
- return cp->state == IP_VS_SCTP_S_CLOSED;
- default:
- return false;
- }
- }
- /* Generic function to create new connections for outgoing RS packets
- *
- * Pre-requisites for successful connection creation:
- * 1) Virtual Service is NOT fwmark based:
- * In fwmark-VS actual vaddr and vport are unknown to IPVS
- * 2) Real Server and Virtual Service were NOT configured without port:
- * This is to allow match of different VS to the same RS ip-addr
- */
- struct ip_vs_conn *ip_vs_new_conn_out(struct ip_vs_service *svc,
- struct ip_vs_dest *dest,
- struct sk_buff *skb,
- const struct ip_vs_iphdr *iph,
- __be16 dport,
- __be16 cport)
- {
- struct ip_vs_conn_param param;
- struct ip_vs_conn *ct = NULL, *cp = NULL;
- const union nf_inet_addr *vaddr, *daddr, *caddr;
- union nf_inet_addr snet;
- __be16 vport;
- unsigned int flags;
- EnterFunction(12);
- vaddr = &svc->addr;
- vport = svc->port;
- daddr = &iph->saddr;
- caddr = &iph->daddr;
- /* check pre-requisites are satisfied */
- if (svc->fwmark)
- return NULL;
- if (!vport || !dport)
- return NULL;
- /* for persistent service first create connection template */
- if (svc->flags & IP_VS_SVC_F_PERSISTENT) {
- /* apply netmask the same way ingress-side does */
- #ifdef CONFIG_IP_VS_IPV6
- if (svc->af == AF_INET6)
- ipv6_addr_prefix(&snet.in6, &caddr->in6,
- (__force __u32)svc->netmask);
- else
- #endif
- snet.ip = caddr->ip & svc->netmask;
- /* fill params and create template if not existent */
- if (ip_vs_conn_fill_param_persist(svc, skb, iph->protocol,
- &snet, 0, vaddr,
- vport, ¶m) < 0)
- return NULL;
- ct = ip_vs_ct_in_get(¶m);
- /* check if template exists and points to the same dest */
- if (!ct || !ip_vs_check_template(ct, dest)) {
- ct = ip_vs_conn_new(¶m, dest->af, daddr, dport,
- IP_VS_CONN_F_TEMPLATE, dest, 0);
- if (!ct) {
- kfree(param.pe_data);
- return NULL;
- }
- ct->timeout = svc->timeout;
- } else {
- kfree(param.pe_data);
- }
- }
- /* connection flags */
- flags = ((svc->flags & IP_VS_SVC_F_ONEPACKET) &&
- iph->protocol == IPPROTO_UDP) ? IP_VS_CONN_F_ONE_PACKET : 0;
- /* create connection */
- ip_vs_conn_fill_param(svc->ipvs, svc->af, iph->protocol,
- caddr, cport, vaddr, vport, ¶m);
- cp = ip_vs_conn_new(¶m, dest->af, daddr, dport, flags, dest, 0);
- if (!cp) {
- if (ct)
- ip_vs_conn_put(ct);
- return NULL;
- }
- if (ct) {
- ip_vs_control_add(cp, ct);
- ip_vs_conn_put(ct);
- }
- ip_vs_conn_stats(cp, svc);
- /* return connection (will be used to handle outgoing packet) */
- IP_VS_DBG_BUF(6, "New connection RS-initiated:%c c:%s:%u v:%s:%u "
- "d:%s:%u conn->flags:%X conn->refcnt:%d\n",
- ip_vs_fwd_tag(cp),
- IP_VS_DBG_ADDR(cp->af, &cp->caddr), ntohs(cp->cport),
- IP_VS_DBG_ADDR(cp->af, &cp->vaddr), ntohs(cp->vport),
- IP_VS_DBG_ADDR(cp->af, &cp->daddr), ntohs(cp->dport),
- cp->flags, refcount_read(&cp->refcnt));
- LeaveFunction(12);
- return cp;
- }
- /* Handle outgoing packets which are considered requests initiated by
- * real servers, so that subsequent responses from external client can be
- * routed to the right real server.
- * Used also for outgoing responses in OPS mode.
- *
- * Connection management is handled by persistent-engine specific callback.
- */
- static struct ip_vs_conn *__ip_vs_rs_conn_out(unsigned int hooknum,
- struct netns_ipvs *ipvs,
- int af, struct sk_buff *skb,
- const struct ip_vs_iphdr *iph)
- {
- struct ip_vs_dest *dest;
- struct ip_vs_conn *cp = NULL;
- __be16 _ports[2], *pptr;
- if (hooknum == NF_INET_LOCAL_IN)
- return NULL;
- pptr = frag_safe_skb_hp(skb, iph->len,
- sizeof(_ports), _ports);
- if (!pptr)
- return NULL;
- dest = ip_vs_find_real_service(ipvs, af, iph->protocol,
- &iph->saddr, pptr[0]);
- if (dest) {
- struct ip_vs_service *svc;
- struct ip_vs_pe *pe;
- svc = rcu_dereference(dest->svc);
- if (svc) {
- pe = rcu_dereference(svc->pe);
- if (pe && pe->conn_out)
- cp = pe->conn_out(svc, dest, skb, iph,
- pptr[0], pptr[1]);
- }
- }
- return cp;
- }
- /* Handle response packets: rewrite addresses and send away...
- */
- static unsigned int
- handle_response(int af, struct sk_buff *skb, struct ip_vs_proto_data *pd,
- struct ip_vs_conn *cp, struct ip_vs_iphdr *iph,
- unsigned int hooknum)
- {
- struct ip_vs_protocol *pp = pd->pp;
- IP_VS_DBG_PKT(11, af, pp, skb, iph->off, "Outgoing packet");
- if (skb_ensure_writable(skb, iph->len))
- goto drop;
- /* mangle the packet */
- if (pp->snat_handler &&
- !SNAT_CALL(pp->snat_handler, skb, pp, cp, iph))
- goto drop;
- #ifdef CONFIG_IP_VS_IPV6
- if (af == AF_INET6)
- ipv6_hdr(skb)->saddr = cp->vaddr.in6;
- else
- #endif
- {
- ip_hdr(skb)->saddr = cp->vaddr.ip;
- ip_send_check(ip_hdr(skb));
- }
- /*
- * nf_iterate does not expect change in the skb->dst->dev.
- * It looks like it is not fatal to enable this code for hooks
- * where our handlers are at the end of the chain list and
- * when all next handlers use skb->dst->dev and not outdev.
- * It will definitely route properly the inout NAT traffic
- * when multiple paths are used.
- */
- /* For policy routing, packets originating from this
- * machine itself may be routed differently to packets
- * passing through. We want this packet to be routed as
- * if it came from this machine itself. So re-compute
- * the routing information.
- */
- if (ip_vs_route_me_harder(cp->ipvs, af, skb, hooknum))
- goto drop;
- IP_VS_DBG_PKT(10, af, pp, skb, iph->off, "After SNAT");
- ip_vs_out_stats(cp, skb);
- ip_vs_set_state(cp, IP_VS_DIR_OUTPUT, skb, pd);
- skb->ipvs_property = 1;
- if (!(cp->flags & IP_VS_CONN_F_NFCT))
- ip_vs_notrack(skb);
- else
- ip_vs_update_conntrack(skb, cp, 0);
- ip_vs_conn_put(cp);
- LeaveFunction(11);
- return NF_ACCEPT;
- drop:
- ip_vs_conn_put(cp);
- kfree_skb(skb);
- LeaveFunction(11);
- return NF_STOLEN;
- }
- /*
- * Check if outgoing packet belongs to the established ip_vs_conn.
- */
- static unsigned int
- ip_vs_out(struct netns_ipvs *ipvs, unsigned int hooknum, struct sk_buff *skb, int af)
- {
- struct ip_vs_iphdr iph;
- struct ip_vs_protocol *pp;
- struct ip_vs_proto_data *pd;
- struct ip_vs_conn *cp;
- struct sock *sk;
- EnterFunction(11);
- /* Already marked as IPVS request or reply? */
- if (skb->ipvs_property)
- return NF_ACCEPT;
- sk = skb_to_full_sk(skb);
- /* Bad... Do not break raw sockets */
- if (unlikely(sk && hooknum == NF_INET_LOCAL_OUT &&
- af == AF_INET)) {
- if (sk->sk_family == PF_INET && inet_sk(sk)->nodefrag)
- return NF_ACCEPT;
- }
- if (unlikely(!skb_dst(skb)))
- return NF_ACCEPT;
- if (!ipvs->enable)
- return NF_ACCEPT;
- ip_vs_fill_iph_skb(af, skb, false, &iph);
- #ifdef CONFIG_IP_VS_IPV6
- if (af == AF_INET6) {
- if (unlikely(iph.protocol == IPPROTO_ICMPV6)) {
- int related;
- int verdict = ip_vs_out_icmp_v6(ipvs, skb, &related,
- hooknum, &iph);
- if (related)
- return verdict;
- }
- } else
- #endif
- if (unlikely(iph.protocol == IPPROTO_ICMP)) {
- int related;
- int verdict = ip_vs_out_icmp(ipvs, skb, &related, hooknum);
- if (related)
- return verdict;
- }
- pd = ip_vs_proto_data_get(ipvs, iph.protocol);
- if (unlikely(!pd))
- return NF_ACCEPT;
- pp = pd->pp;
- /* reassemble IP fragments */
- #ifdef CONFIG_IP_VS_IPV6
- if (af == AF_INET)
- #endif
- if (unlikely(ip_is_fragment(ip_hdr(skb)) && !pp->dont_defrag)) {
- if (ip_vs_gather_frags(ipvs, skb,
- ip_vs_defrag_user(hooknum)))
- return NF_STOLEN;
- ip_vs_fill_iph_skb(AF_INET, skb, false, &iph);
- }
- /*
- * Check if the packet belongs to an existing entry
- */
- cp = INDIRECT_CALL_1(pp->conn_out_get, ip_vs_conn_out_get_proto,
- ipvs, af, skb, &iph);
- if (likely(cp)) {
- if (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ)
- goto ignore_cp;
- return handle_response(af, skb, pd, cp, &iph, hooknum);
- }
- /* Check for real-server-started requests */
- if (atomic_read(&ipvs->conn_out_counter)) {
- /* Currently only for UDP:
- * connection oriented protocols typically use
- * ephemeral ports for outgoing connections, so
- * related incoming responses would not match any VS
- */
- if (pp->protocol == IPPROTO_UDP) {
- cp = __ip_vs_rs_conn_out(hooknum, ipvs, af, skb, &iph);
- if (likely(cp))
- return handle_response(af, skb, pd, cp, &iph,
- hooknum);
- }
- }
- if (sysctl_nat_icmp_send(ipvs) &&
- (pp->protocol == IPPROTO_TCP ||
- pp->protocol == IPPROTO_UDP ||
- pp->protocol == IPPROTO_SCTP)) {
- __be16 _ports[2], *pptr;
- pptr = frag_safe_skb_hp(skb, iph.len,
- sizeof(_ports), _ports);
- if (pptr == NULL)
- return NF_ACCEPT; /* Not for me */
- if (ip_vs_has_real_service(ipvs, af, iph.protocol, &iph.saddr,
- pptr[0])) {
- /*
- * Notify the real server: there is no
- * existing entry if it is not RST
- * packet or not TCP packet.
- */
- if ((iph.protocol != IPPROTO_TCP &&
- iph.protocol != IPPROTO_SCTP)
- || ((iph.protocol == IPPROTO_TCP
- && !is_tcp_reset(skb, iph.len))
- || (iph.protocol == IPPROTO_SCTP
- && !is_sctp_abort(skb,
- iph.len)))) {
- #ifdef CONFIG_IP_VS_IPV6
- if (af == AF_INET6) {
- if (!skb->dev)
- skb->dev = ipvs->net->loopback_dev;
- icmpv6_send(skb,
- ICMPV6_DEST_UNREACH,
- ICMPV6_PORT_UNREACH,
- 0);
- } else
- #endif
- icmp_send(skb,
- ICMP_DEST_UNREACH,
- ICMP_PORT_UNREACH, 0);
- return NF_DROP;
- }
- }
- }
- out:
- IP_VS_DBG_PKT(12, af, pp, skb, iph.off,
- "ip_vs_out: packet continues traversal as normal");
- return NF_ACCEPT;
- ignore_cp:
- __ip_vs_conn_put(cp);
- goto out;
- }
- /*
- * It is hooked at the NF_INET_FORWARD and NF_INET_LOCAL_IN chain,
- * used only for VS/NAT.
- * Check if packet is reply for established ip_vs_conn.
- */
- static unsigned int
- ip_vs_reply4(void *priv, struct sk_buff *skb,
- const struct nf_hook_state *state)
- {
- return ip_vs_out(net_ipvs(state->net), state->hook, skb, AF_INET);
- }
- /*
- * It is hooked at the NF_INET_LOCAL_OUT chain, used only for VS/NAT.
- * Check if packet is reply for established ip_vs_conn.
- */
- static unsigned int
- ip_vs_local_reply4(void *priv, struct sk_buff *skb,
- const struct nf_hook_state *state)
- {
- return ip_vs_out(net_ipvs(state->net), state->hook, skb, AF_INET);
- }
- #ifdef CONFIG_IP_VS_IPV6
- /*
- * It is hooked at the NF_INET_FORWARD and NF_INET_LOCAL_IN chain,
- * used only for VS/NAT.
- * Check if packet is reply for established ip_vs_conn.
- */
- static unsigned int
- ip_vs_reply6(void *priv, struct sk_buff *skb,
- const struct nf_hook_state *state)
- {
- return ip_vs_out(net_ipvs(state->net), state->hook, skb, AF_INET6);
- }
- /*
- * It is hooked at the NF_INET_LOCAL_OUT chain, used only for VS/NAT.
- * Check if packet is reply for established ip_vs_conn.
- */
- static unsigned int
- ip_vs_local_reply6(void *priv, struct sk_buff *skb,
- const struct nf_hook_state *state)
- {
- return ip_vs_out(net_ipvs(state->net), state->hook, skb, AF_INET6);
- }
- #endif
- static unsigned int
- ip_vs_try_to_schedule(struct netns_ipvs *ipvs, int af, struct sk_buff *skb,
- struct ip_vs_proto_data *pd,
- int *verdict, struct ip_vs_conn **cpp,
- struct ip_vs_iphdr *iph)
- {
- struct ip_vs_protocol *pp = pd->pp;
- if (!iph->fragoffs) {
- /* No (second) fragments need to enter here, as nf_defrag_ipv6
- * replayed fragment zero will already have created the cp
- */
- /* Schedule and create new connection entry into cpp */
- if (!pp->conn_schedule(ipvs, af, skb, pd, verdict, cpp, iph))
- return 0;
- }
- if (unlikely(!*cpp)) {
- /* sorry, all this trouble for a no-hit :) */
- IP_VS_DBG_PKT(12, af, pp, skb, iph->off,
- "ip_vs_in: packet continues traversal as normal");
- /* Fragment couldn't be mapped to a conn entry */
- if (iph->fragoffs)
- IP_VS_DBG_PKT(7, af, pp, skb, iph->off,
- "unhandled fragment");
- *verdict = NF_ACCEPT;
- return 0;
- }
- return 1;
- }
- /* Check the UDP tunnel and return its header length */
- static int ipvs_udp_decap(struct netns_ipvs *ipvs, struct sk_buff *skb,
- unsigned int offset, __u16 af,
- const union nf_inet_addr *daddr, __u8 *proto)
- {
- struct udphdr _udph, *udph;
- struct ip_vs_dest *dest;
- udph = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
- if (!udph)
- goto unk;
- offset += sizeof(struct udphdr);
- dest = ip_vs_find_tunnel(ipvs, af, daddr, udph->dest);
- if (!dest)
- goto unk;
- if (dest->tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE) {
- struct guehdr _gueh, *gueh;
- gueh = skb_header_pointer(skb, offset, sizeof(_gueh), &_gueh);
- if (!gueh)
- goto unk;
- if (gueh->control != 0 || gueh->version != 0)
- goto unk;
- /* Later we can support also IPPROTO_IPV6 */
- if (gueh->proto_ctype != IPPROTO_IPIP)
- goto unk;
- *proto = gueh->proto_ctype;
- return sizeof(struct udphdr) + sizeof(struct guehdr) +
- (gueh->hlen << 2);
- }
- unk:
- return 0;
- }
- /* Check the GRE tunnel and return its header length */
- static int ipvs_gre_decap(struct netns_ipvs *ipvs, struct sk_buff *skb,
- unsigned int offset, __u16 af,
- const union nf_inet_addr *daddr, __u8 *proto)
- {
- struct gre_base_hdr _greh, *greh;
- struct ip_vs_dest *dest;
- greh = skb_header_pointer(skb, offset, sizeof(_greh), &_greh);
- if (!greh)
- goto unk;
- dest = ip_vs_find_tunnel(ipvs, af, daddr, 0);
- if (!dest)
- goto unk;
- if (dest->tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GRE) {
- __be16 type;
- /* Only support version 0 and C (csum) */
- if ((greh->flags & ~GRE_CSUM) != 0)
- goto unk;
- type = greh->protocol;
- /* Later we can support also IPPROTO_IPV6 */
- if (type != htons(ETH_P_IP))
- goto unk;
- *proto = IPPROTO_IPIP;
- return gre_calc_hlen(gre_flags_to_tnl_flags(greh->flags));
- }
- unk:
- return 0;
- }
- /*
- * Handle ICMP messages in the outside-to-inside direction (incoming).
- * Find any that might be relevant, check against existing connections,
- * forward to the right destination host if relevant.
- * Currently handles error types - unreachable, quench, ttl exceeded.
- */
- static int
- ip_vs_in_icmp(struct netns_ipvs *ipvs, struct sk_buff *skb, int *related,
- unsigned int hooknum)
- {
- struct iphdr *iph;
- struct icmphdr _icmph, *ic;
- struct iphdr _ciph, *cih; /* The ip header contained within the ICMP */
- struct ip_vs_iphdr ciph;
- struct ip_vs_conn *cp;
- struct ip_vs_protocol *pp;
- struct ip_vs_proto_data *pd;
- unsigned int offset, offset2, ihl, verdict;
- bool tunnel, new_cp = false;
- union nf_inet_addr *raddr;
- char *outer_proto = "IPIP";
- *related = 1;
- /* reassemble IP fragments */
- if (ip_is_fragment(ip_hdr(skb))) {
- if (ip_vs_gather_frags(ipvs, skb, ip_vs_defrag_user(hooknum)))
- return NF_STOLEN;
- }
- iph = ip_hdr(skb);
- offset = ihl = iph->ihl * 4;
- ic = skb_header_pointer(skb, offset, sizeof(_icmph), &_icmph);
- if (ic == NULL)
- return NF_DROP;
- IP_VS_DBG(12, "Incoming ICMP (%d,%d) %pI4->%pI4\n",
- ic->type, ntohs(icmp_id(ic)),
- &iph->saddr, &iph->daddr);
- /*
- * Work through seeing if this is for us.
- * These checks are supposed to be in an order that means easy
- * things are checked first to speed up processing.... however
- * this means that some packets will manage to get a long way
- * down this stack and then be rejected, but that's life.
- */
- if ((ic->type != ICMP_DEST_UNREACH) &&
- (ic->type != ICMP_SOURCE_QUENCH) &&
- (ic->type != ICMP_TIME_EXCEEDED)) {
- *related = 0;
- return NF_ACCEPT;
- }
- /* Now find the contained IP header */
- offset += sizeof(_icmph);
- cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
- if (cih == NULL)
- return NF_ACCEPT; /* The packet looks wrong, ignore */
- raddr = (union nf_inet_addr *)&cih->daddr;
- /* Special case for errors for IPIP/UDP/GRE tunnel packets */
- tunnel = false;
- if (cih->protocol == IPPROTO_IPIP) {
- struct ip_vs_dest *dest;
- if (unlikely(cih->frag_off & htons(IP_OFFSET)))
- return NF_ACCEPT;
- /* Error for our IPIP must arrive at LOCAL_IN */
- if (!(skb_rtable(skb)->rt_flags & RTCF_LOCAL))
- return NF_ACCEPT;
- dest = ip_vs_find_tunnel(ipvs, AF_INET, raddr, 0);
- /* Only for known tunnel */
- if (!dest || dest->tun_type != IP_VS_CONN_F_TUNNEL_TYPE_IPIP)
- return NF_ACCEPT;
- offset += cih->ihl * 4;
- cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
- if (cih == NULL)
- return NF_ACCEPT; /* The packet looks wrong, ignore */
- tunnel = true;
- } else if ((cih->protocol == IPPROTO_UDP || /* Can be UDP encap */
- cih->protocol == IPPROTO_GRE) && /* Can be GRE encap */
- /* Error for our tunnel must arrive at LOCAL_IN */
- (skb_rtable(skb)->rt_flags & RTCF_LOCAL)) {
- __u8 iproto;
- int ulen;
- /* Non-first fragment has no UDP/GRE header */
- if (unlikely(cih->frag_off & htons(IP_OFFSET)))
- return NF_ACCEPT;
- offset2 = offset + cih->ihl * 4;
- if (cih->protocol == IPPROTO_UDP) {
- ulen = ipvs_udp_decap(ipvs, skb, offset2, AF_INET,
- raddr, &iproto);
- outer_proto = "UDP";
- } else {
- ulen = ipvs_gre_decap(ipvs, skb, offset2, AF_INET,
- raddr, &iproto);
- outer_proto = "GRE";
- }
- if (ulen > 0) {
- /* Skip IP and UDP/GRE tunnel headers */
- offset = offset2 + ulen;
- /* Now we should be at the original IP header */
- cih = skb_header_pointer(skb, offset, sizeof(_ciph),
- &_ciph);
- if (cih && cih->version == 4 && cih->ihl >= 5 &&
- iproto == IPPROTO_IPIP)
- tunnel = true;
- else
- return NF_ACCEPT;
- }
- }
- pd = ip_vs_proto_data_get(ipvs, cih->protocol);
- if (!pd)
- return NF_ACCEPT;
- pp = pd->pp;
- /* Is the embedded protocol header present? */
- if (unlikely(cih->frag_off & htons(IP_OFFSET) &&
- pp->dont_defrag))
- return NF_ACCEPT;
- IP_VS_DBG_PKT(11, AF_INET, pp, skb, offset,
- "Checking incoming ICMP for");
- offset2 = offset;
- ip_vs_fill_iph_skb_icmp(AF_INET, skb, offset, !tunnel, &ciph);
- offset = ciph.len;
- /* The embedded headers contain source and dest in reverse order.
- * For IPIP/UDP/GRE tunnel this is error for request, not for reply.
- */
- cp = INDIRECT_CALL_1(pp->conn_in_get, ip_vs_conn_in_get_proto,
- ipvs, AF_INET, skb, &ciph);
- if (!cp) {
- int v;
- if (tunnel || !sysctl_schedule_icmp(ipvs))
- return NF_ACCEPT;
- if (!ip_vs_try_to_schedule(ipvs, AF_INET, skb, pd, &v, &cp, &ciph))
- return v;
- new_cp = true;
- }
- verdict = NF_DROP;
- /* Ensure the checksum is correct */
- if (!skb_csum_unnecessary(skb) && ip_vs_checksum_complete(skb, ihl)) {
- /* Failed checksum! */
- IP_VS_DBG(1, "Incoming ICMP: failed checksum from %pI4!\n",
- &iph->saddr);
- goto out;
- }
- if (tunnel) {
- __be32 info = ic->un.gateway;
- __u8 type = ic->type;
- __u8 code = ic->code;
- /* Update the MTU */
- if (ic->type == ICMP_DEST_UNREACH &&
- ic->code == ICMP_FRAG_NEEDED) {
- struct ip_vs_dest *dest = cp->dest;
- u32 mtu = ntohs(ic->un.frag.mtu);
- __be16 frag_off = cih->frag_off;
- /* Strip outer IP and ICMP, go to IPIP/UDP/GRE header */
- if (pskb_pull(skb, ihl + sizeof(_icmph)) == NULL)
- goto ignore_tunnel;
- offset2 -= ihl + sizeof(_icmph);
- skb_reset_network_header(skb);
- IP_VS_DBG(12, "ICMP for %s %pI4->%pI4: mtu=%u\n",
- outer_proto, &ip_hdr(skb)->saddr,
- &ip_hdr(skb)->daddr, mtu);
- ipv4_update_pmtu(skb, ipvs->net, mtu, 0, 0);
- /* Client uses PMTUD? */
- if (!(frag_off & htons(IP_DF)))
- goto ignore_tunnel;
- /* Prefer the resulting PMTU */
- if (dest) {
- struct ip_vs_dest_dst *dest_dst;
- dest_dst = rcu_dereference(dest->dest_dst);
- if (dest_dst)
- mtu = dst_mtu(dest_dst->dst_cache);
- }
- if (mtu > 68 + sizeof(struct iphdr))
- mtu -= sizeof(struct iphdr);
- info = htonl(mtu);
- }
- /* Strip outer IP, ICMP and IPIP/UDP/GRE, go to IP header of
- * original request.
- */
- if (pskb_pull(skb, offset2) == NULL)
- goto ignore_tunnel;
- skb_reset_network_header(skb);
- IP_VS_DBG(12, "Sending ICMP for %pI4->%pI4: t=%u, c=%u, i=%u\n",
- &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr,
- type, code, ntohl(info));
- icmp_send(skb, type, code, info);
- /* ICMP can be shorter but anyways, account it */
- ip_vs_out_stats(cp, skb);
- ignore_tunnel:
- consume_skb(skb);
- verdict = NF_STOLEN;
- goto out;
- }
- /* do the statistics and put it back */
- ip_vs_in_stats(cp, skb);
- if (IPPROTO_TCP == cih->protocol || IPPROTO_UDP == cih->protocol ||
- IPPROTO_SCTP == cih->protocol)
- offset += 2 * sizeof(__u16);
- verdict = ip_vs_icmp_xmit(skb, cp, pp, offset, hooknum, &ciph);
- out:
- if (likely(!new_cp))
- __ip_vs_conn_put(cp);
- else
- ip_vs_conn_put(cp);
- return verdict;
- }
- #ifdef CONFIG_IP_VS_IPV6
- static int ip_vs_in_icmp_v6(struct netns_ipvs *ipvs, struct sk_buff *skb,
- int *related, unsigned int hooknum,
- struct ip_vs_iphdr *iph)
- {
- struct icmp6hdr _icmph, *ic;
- struct ip_vs_iphdr ciph = {.flags = 0, .fragoffs = 0};/*Contained IP */
- struct ip_vs_conn *cp;
- struct ip_vs_protocol *pp;
- struct ip_vs_proto_data *pd;
- unsigned int offset, verdict;
- bool new_cp = false;
- *related = 1;
- ic = frag_safe_skb_hp(skb, iph->len, sizeof(_icmph), &_icmph);
- if (ic == NULL)
- return NF_DROP;
- /*
- * Work through seeing if this is for us.
- * These checks are supposed to be in an order that means easy
- * things are checked first to speed up processing.... however
- * this means that some packets will manage to get a long way
- * down this stack and then be rejected, but that's life.
- */
- if (ic->icmp6_type & ICMPV6_INFOMSG_MASK) {
- *related = 0;
- return NF_ACCEPT;
- }
- /* Fragment header that is before ICMP header tells us that:
- * it's not an error message since they can't be fragmented.
- */
- if (iph->flags & IP6_FH_F_FRAG)
- return NF_DROP;
- IP_VS_DBG(8, "Incoming ICMPv6 (%d,%d) %pI6c->%pI6c\n",
- ic->icmp6_type, ntohs(icmpv6_id(ic)),
- &iph->saddr, &iph->daddr);
- offset = iph->len + sizeof(_icmph);
- if (!ip_vs_fill_iph_skb_icmp(AF_INET6, skb, offset, true, &ciph))
- return NF_ACCEPT;
- pd = ip_vs_proto_data_get(ipvs, ciph.protocol);
- if (!pd)
- return NF_ACCEPT;
- pp = pd->pp;
- /* Cannot handle fragmented embedded protocol */
- if (ciph.fragoffs)
- return NF_ACCEPT;
- IP_VS_DBG_PKT(11, AF_INET6, pp, skb, offset,
- "Checking incoming ICMPv6 for");
- /* The embedded headers contain source and dest in reverse order
- * if not from localhost
- */
- cp = INDIRECT_CALL_1(pp->conn_in_get, ip_vs_conn_in_get_proto,
- ipvs, AF_INET6, skb, &ciph);
- if (!cp) {
- int v;
- if (!sysctl_schedule_icmp(ipvs))
- return NF_ACCEPT;
- if (!ip_vs_try_to_schedule(ipvs, AF_INET6, skb, pd, &v, &cp, &ciph))
- return v;
- new_cp = true;
- }
- /* VS/TUN, VS/DR and LOCALNODE just let it go */
- if ((hooknum == NF_INET_LOCAL_OUT) &&
- (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ)) {
- verdict = NF_ACCEPT;
- goto out;
- }
- /* do the statistics and put it back */
- ip_vs_in_stats(cp, skb);
- /* Need to mangle contained IPv6 header in ICMPv6 packet */
- offset = ciph.len;
- if (IPPROTO_TCP == ciph.protocol || IPPROTO_UDP == ciph.protocol ||
- IPPROTO_SCTP == ciph.protocol)
- offset += 2 * sizeof(__u16); /* Also mangle ports */
- verdict = ip_vs_icmp_xmit_v6(skb, cp, pp, offset, hooknum, &ciph);
- out:
- if (likely(!new_cp))
- __ip_vs_conn_put(cp);
- else
- ip_vs_conn_put(cp);
- return verdict;
- }
- #endif
- /*
- * Check if it's for virtual services, look it up,
- * and send it on its way...
- */
- static unsigned int
- ip_vs_in(struct netns_ipvs *ipvs, unsigned int hooknum, struct sk_buff *skb, int af)
- {
- struct ip_vs_iphdr iph;
- struct ip_vs_protocol *pp;
- struct ip_vs_proto_data *pd;
- struct ip_vs_conn *cp;
- int ret, pkts;
- int conn_reuse_mode;
- struct sock *sk;
- /* Already marked as IPVS request or reply? */
- if (skb->ipvs_property)
- return NF_ACCEPT;
- /*
- * Big tappo:
- * - remote client: only PACKET_HOST
- * - route: used for struct net when skb->dev is unset
- */
- if (unlikely((skb->pkt_type != PACKET_HOST &&
- hooknum != NF_INET_LOCAL_OUT) ||
- !skb_dst(skb))) {
- ip_vs_fill_iph_skb(af, skb, false, &iph);
- IP_VS_DBG_BUF(12, "packet type=%d proto=%d daddr=%s"
- " ignored in hook %u\n",
- skb->pkt_type, iph.protocol,
- IP_VS_DBG_ADDR(af, &iph.daddr), hooknum);
- return NF_ACCEPT;
- }
- /* ipvs enabled in this netns ? */
- if (unlikely(sysctl_backup_only(ipvs) || !ipvs->enable))
- return NF_ACCEPT;
- ip_vs_fill_iph_skb(af, skb, false, &iph);
- /* Bad... Do not break raw sockets */
- sk = skb_to_full_sk(skb);
- if (unlikely(sk && hooknum == NF_INET_LOCAL_OUT &&
- af == AF_INET)) {
- if (sk->sk_family == PF_INET && inet_sk(sk)->nodefrag)
- return NF_ACCEPT;
- }
- #ifdef CONFIG_IP_VS_IPV6
- if (af == AF_INET6) {
- if (unlikely(iph.protocol == IPPROTO_ICMPV6)) {
- int related;
- int verdict = ip_vs_in_icmp_v6(ipvs, skb, &related,
- hooknum, &iph);
- if (related)
- return verdict;
- }
- } else
- #endif
- if (unlikely(iph.protocol == IPPROTO_ICMP)) {
- int related;
- int verdict = ip_vs_in_icmp(ipvs, skb, &related,
- hooknum);
- if (related)
- return verdict;
- }
- /* Protocol supported? */
- pd = ip_vs_proto_data_get(ipvs, iph.protocol);
- if (unlikely(!pd)) {
- /* The only way we'll see this packet again is if it's
- * encapsulated, so mark it with ipvs_property=1 so we
- * skip it if we're ignoring tunneled packets
- */
- if (sysctl_ignore_tunneled(ipvs))
- skb->ipvs_property = 1;
- return NF_ACCEPT;
- }
- pp = pd->pp;
- /*
- * Check if the packet belongs to an existing connection entry
- */
- cp = INDIRECT_CALL_1(pp->conn_in_get, ip_vs_conn_in_get_proto,
- ipvs, af, skb, &iph);
- conn_reuse_mode = sysctl_conn_reuse_mode(ipvs);
- if (conn_reuse_mode && !iph.fragoffs && is_new_conn(skb, &iph) && cp) {
- bool uses_ct = false, resched = false;
- if (unlikely(sysctl_expire_nodest_conn(ipvs)) && cp->dest &&
- unlikely(!atomic_read(&cp->dest->weight))) {
- resched = true;
- uses_ct = ip_vs_conn_uses_conntrack(cp, skb);
- } else if (is_new_conn_expected(cp, conn_reuse_mode)) {
- uses_ct = ip_vs_conn_uses_conntrack(cp, skb);
- if (!atomic_read(&cp->n_control)) {
- resched = true;
- } else {
- /* Do not reschedule controlling connection
- * that uses conntrack while it is still
- * referenced by controlled connection(s).
- */
- resched = !uses_ct;
- }
- }
- if (resched) {
- if (!atomic_read(&cp->n_control))
- ip_vs_conn_expire_now(cp);
- __ip_vs_conn_put(cp);
- if (uses_ct)
- return NF_DROP;
- cp = NULL;
- }
- }
- if (unlikely(!cp)) {
- int v;
- if (!ip_vs_try_to_schedule(ipvs, af, skb, pd, &v, &cp, &iph))
- return v;
- }
- IP_VS_DBG_PKT(11, af, pp, skb, iph.off, "Incoming packet");
- /* Check the server status */
- if (cp->dest && !(cp->dest->flags & IP_VS_DEST_F_AVAILABLE)) {
- /* the destination server is not available */
- __u32 flags = cp->flags;
- /* when timer already started, silently drop the packet.*/
- if (timer_pending(&cp->timer))
- __ip_vs_conn_put(cp);
- else
- ip_vs_conn_put(cp);
- if (sysctl_expire_nodest_conn(ipvs) &&
- !(flags & IP_VS_CONN_F_ONE_PACKET)) {
- /* try to expire the connection immediately */
- ip_vs_conn_expire_now(cp);
- }
- return NF_DROP;
- }
- ip_vs_in_stats(cp, skb);
- ip_vs_set_state(cp, IP_VS_DIR_INPUT, skb, pd);
- if (cp->packet_xmit)
- ret = cp->packet_xmit(skb, cp, pp, &iph);
- /* do not touch skb anymore */
- else {
- IP_VS_DBG_RL("warning: packet_xmit is null");
- ret = NF_ACCEPT;
- }
- /* Increase its packet counter and check if it is needed
- * to be synchronized
- *
- * Sync connection if it is about to close to
- * encorage the standby servers to update the connections timeout
- *
- * For ONE_PKT let ip_vs_sync_conn() do the filter work.
- */
- if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
- pkts = sysctl_sync_threshold(ipvs);
- else
- pkts = atomic_add_return(1, &cp->in_pkts);
- if (ipvs->sync_state & IP_VS_STATE_MASTER)
- ip_vs_sync_conn(ipvs, cp, pkts);
- else if ((cp->flags & IP_VS_CONN_F_ONE_PACKET) && cp->control)
- /* increment is done inside ip_vs_sync_conn too */
- atomic_inc(&cp->control->in_pkts);
- ip_vs_conn_put(cp);
- return ret;
- }
- /*
- * AF_INET handler in NF_INET_LOCAL_IN chain
- * Schedule and forward packets from remote clients
- */
- static unsigned int
- ip_vs_remote_request4(void *priv, struct sk_buff *skb,
- const struct nf_hook_state *state)
- {
- return ip_vs_in(net_ipvs(state->net), state->hook, skb, AF_INET);
- }
- /*
- * AF_INET handler in NF_INET_LOCAL_OUT chain
- * Schedule and forward packets from local clients
- */
- static unsigned int
- ip_vs_local_request4(void *priv, struct sk_buff *skb,
- const struct nf_hook_state *state)
- {
- return ip_vs_in(net_ipvs(state->net), state->hook, skb, AF_INET);
- }
- #ifdef CONFIG_IP_VS_IPV6
- /*
- * AF_INET6 handler in NF_INET_LOCAL_IN chain
- * Schedule and forward packets from remote clients
- */
- static unsigned int
- ip_vs_remote_request6(void *priv, struct sk_buff *skb,
- const struct nf_hook_state *state)
- {
- return ip_vs_in(net_ipvs(state->net), state->hook, skb, AF_INET6);
- }
- /*
- * AF_INET6 handler in NF_INET_LOCAL_OUT chain
- * Schedule and forward packets from local clients
- */
- static unsigned int
- ip_vs_local_request6(void *priv, struct sk_buff *skb,
- const struct nf_hook_state *state)
- {
- return ip_vs_in(net_ipvs(state->net), state->hook, skb, AF_INET6);
- }
- #endif
- /*
- * It is hooked at the NF_INET_FORWARD chain, in order to catch ICMP
- * related packets destined for 0.0.0.0/0.
- * When fwmark-based virtual service is used, such as transparent
- * cache cluster, TCP packets can be marked and routed to ip_vs_in,
- * but ICMP destined for 0.0.0.0/0 cannot not be easily marked and
- * sent to ip_vs_in_icmp. So, catch them at the NF_INET_FORWARD chain
- * and send them to ip_vs_in_icmp.
- */
- static unsigned int
- ip_vs_forward_icmp(void *priv, struct sk_buff *skb,
- const struct nf_hook_state *state)
- {
- int r;
- struct netns_ipvs *ipvs = net_ipvs(state->net);
- if (ip_hdr(skb)->protocol != IPPROTO_ICMP)
- return NF_ACCEPT;
- /* ipvs enabled in this netns ? */
- if (unlikely(sysctl_backup_only(ipvs) || !ipvs->enable))
- return NF_ACCEPT;
- return ip_vs_in_icmp(ipvs, skb, &r, state->hook);
- }
- #ifdef CONFIG_IP_VS_IPV6
- static unsigned int
- ip_vs_forward_icmp_v6(void *priv, struct sk_buff *skb,
- const struct nf_hook_state *state)
- {
- int r;
- struct netns_ipvs *ipvs = net_ipvs(state->net);
- struct ip_vs_iphdr iphdr;
- ip_vs_fill_iph_skb(AF_INET6, skb, false, &iphdr);
- if (iphdr.protocol != IPPROTO_ICMPV6)
- return NF_ACCEPT;
- /* ipvs enabled in this netns ? */
- if (unlikely(sysctl_backup_only(ipvs) || !ipvs->enable))
- return NF_ACCEPT;
- return ip_vs_in_icmp_v6(ipvs, skb, &r, state->hook, &iphdr);
- }
- #endif
- static const struct nf_hook_ops ip_vs_ops[] = {
- /* After packet filtering, change source only for VS/NAT */
- {
- .hook = ip_vs_reply4,
- .pf = NFPROTO_IPV4,
- .hooknum = NF_INET_LOCAL_IN,
- .priority = NF_IP_PRI_NAT_SRC - 2,
- },
- /* After packet filtering, forward packet through VS/DR, VS/TUN,
- * or VS/NAT(change destination), so that filtering rules can be
- * applied to IPVS. */
- {
- .hook = ip_vs_remote_request4,
- .pf = NFPROTO_IPV4,
- .hooknum = NF_INET_LOCAL_IN,
- .priority = NF_IP_PRI_NAT_SRC - 1,
- },
- /* Before ip_vs_in, change source only for VS/NAT */
- {
- .hook = ip_vs_local_reply4,
- .pf = NFPROTO_IPV4,
- .hooknum = NF_INET_LOCAL_OUT,
- .priority = NF_IP_PRI_NAT_DST + 1,
- },
- /* After mangle, schedule and forward local requests */
- {
- .hook = ip_vs_local_request4,
- .pf = NFPROTO_IPV4,
- .hooknum = NF_INET_LOCAL_OUT,
- .priority = NF_IP_PRI_NAT_DST + 2,
- },
- /* After packet filtering (but before ip_vs_out_icmp), catch icmp
- * destined for 0.0.0.0/0, which is for incoming IPVS connections */
- {
- .hook = ip_vs_forward_icmp,
- .pf = NFPROTO_IPV4,
- .hooknum = NF_INET_FORWARD,
- .priority = 99,
- },
- /* After packet filtering, change source only for VS/NAT */
- {
- .hook = ip_vs_reply4,
- .pf = NFPROTO_IPV4,
- .hooknum = NF_INET_FORWARD,
- .priority = 100,
- },
- #ifdef CONFIG_IP_VS_IPV6
- /* After packet filtering, change source only for VS/NAT */
- {
- .hook = ip_vs_reply6,
- .pf = NFPROTO_IPV6,
- .hooknum = NF_INET_LOCAL_IN,
- .priority = NF_IP6_PRI_NAT_SRC - 2,
- },
- /* After packet filtering, forward packet through VS/DR, VS/TUN,
- * or VS/NAT(change destination), so that filtering rules can be
- * applied to IPVS. */
- {
- .hook = ip_vs_remote_request6,
- .pf = NFPROTO_IPV6,
- .hooknum = NF_INET_LOCAL_IN,
- .priority = NF_IP6_PRI_NAT_SRC - 1,
- },
- /* Before ip_vs_in, change source only for VS/NAT */
- {
- .hook = ip_vs_local_reply6,
- .pf = NFPROTO_IPV6,
- .hooknum = NF_INET_LOCAL_OUT,
- .priority = NF_IP6_PRI_NAT_DST + 1,
- },
- /* After mangle, schedule and forward local requests */
- {
- .hook = ip_vs_local_request6,
- .pf = NFPROTO_IPV6,
- .hooknum = NF_INET_LOCAL_OUT,
- .priority = NF_IP6_PRI_NAT_DST + 2,
- },
- /* After packet filtering (but before ip_vs_out_icmp), catch icmp
- * destined for 0.0.0.0/0, which is for incoming IPVS connections */
- {
- .hook = ip_vs_forward_icmp_v6,
- .pf = NFPROTO_IPV6,
- .hooknum = NF_INET_FORWARD,
- .priority = 99,
- },
- /* After packet filtering, change source only for VS/NAT */
- {
- .hook = ip_vs_reply6,
- .pf = NFPROTO_IPV6,
- .hooknum = NF_INET_FORWARD,
- .priority = 100,
- },
- #endif
- };
- /*
- * Initialize IP Virtual Server netns mem.
- */
- static int __net_init __ip_vs_init(struct net *net)
- {
- struct netns_ipvs *ipvs;
- ipvs = net_generic(net, ip_vs_net_id);
- if (ipvs == NULL)
- return -ENOMEM;
- /* Hold the beast until a service is registerd */
- ipvs->enable = 0;
- ipvs->net = net;
- /* Counters used for creating unique names */
- ipvs->gen = atomic_read(&ipvs_netns_cnt);
- atomic_inc(&ipvs_netns_cnt);
- net->ipvs = ipvs;
- if (ip_vs_estimator_net_init(ipvs) < 0)
- goto estimator_fail;
- if (ip_vs_control_net_init(ipvs) < 0)
- goto control_fail;
- if (ip_vs_protocol_net_init(ipvs) < 0)
- goto protocol_fail;
- if (ip_vs_app_net_init(ipvs) < 0)
- goto app_fail;
- if (ip_vs_conn_net_init(ipvs) < 0)
- goto conn_fail;
- if (ip_vs_sync_net_init(ipvs) < 0)
- goto sync_fail;
- return 0;
- /*
- * Error handling
- */
- sync_fail:
- ip_vs_conn_net_cleanup(ipvs);
- conn_fail:
- ip_vs_app_net_cleanup(ipvs);
- app_fail:
- ip_vs_protocol_net_cleanup(ipvs);
- protocol_fail:
- ip_vs_control_net_cleanup(ipvs);
- control_fail:
- ip_vs_estimator_net_cleanup(ipvs);
- estimator_fail:
- net->ipvs = NULL;
- return -ENOMEM;
- }
- static void __net_exit __ip_vs_cleanup_batch(struct list_head *net_list)
- {
- struct netns_ipvs *ipvs;
- struct net *net;
- ip_vs_service_nets_cleanup(net_list); /* ip_vs_flush() with locks */
- list_for_each_entry(net, net_list, exit_list) {
- ipvs = net_ipvs(net);
- ip_vs_conn_net_cleanup(ipvs);
- ip_vs_app_net_cleanup(ipvs);
- ip_vs_protocol_net_cleanup(ipvs);
- ip_vs_control_net_cleanup(ipvs);
- ip_vs_estimator_net_cleanup(ipvs);
- IP_VS_DBG(2, "ipvs netns %d released\n", ipvs->gen);
- net->ipvs = NULL;
- }
- }
- static int __net_init __ip_vs_dev_init(struct net *net)
- {
- int ret;
- ret = nf_register_net_hooks(net, ip_vs_ops, ARRAY_SIZE(ip_vs_ops));
- if (ret < 0)
- goto hook_fail;
- return 0;
- hook_fail:
- return ret;
- }
- static void __net_exit __ip_vs_dev_cleanup_batch(struct list_head *net_list)
- {
- struct netns_ipvs *ipvs;
- struct net *net;
- EnterFunction(2);
- list_for_each_entry(net, net_list, exit_list) {
- ipvs = net_ipvs(net);
- nf_unregister_net_hooks(net, ip_vs_ops, ARRAY_SIZE(ip_vs_ops));
- ipvs->enable = 0; /* Disable packet reception */
- smp_wmb();
- ip_vs_sync_net_cleanup(ipvs);
- }
- LeaveFunction(2);
- }
- static struct pernet_operations ipvs_core_ops = {
- .init = __ip_vs_init,
- .exit_batch = __ip_vs_cleanup_batch,
- .id = &ip_vs_net_id,
- .size = sizeof(struct netns_ipvs),
- };
- static struct pernet_operations ipvs_core_dev_ops = {
- .init = __ip_vs_dev_init,
- .exit_batch = __ip_vs_dev_cleanup_batch,
- };
- /*
- * Initialize IP Virtual Server
- */
- static int __init ip_vs_init(void)
- {
- int ret;
- ret = ip_vs_control_init();
- if (ret < 0) {
- pr_err("can't setup control.\n");
- goto exit;
- }
- ip_vs_protocol_init();
- ret = ip_vs_conn_init();
- if (ret < 0) {
- pr_err("can't setup connection table.\n");
- goto cleanup_protocol;
- }
- ret = register_pernet_subsys(&ipvs_core_ops); /* Alloc ip_vs struct */
- if (ret < 0)
- goto cleanup_conn;
- ret = register_pernet_device(&ipvs_core_dev_ops);
- if (ret < 0)
- goto cleanup_sub;
- ret = ip_vs_register_nl_ioctl();
- if (ret < 0) {
- pr_err("can't register netlink/ioctl.\n");
- goto cleanup_dev;
- }
- pr_info("ipvs loaded.\n");
- return ret;
- cleanup_dev:
- unregister_pernet_device(&ipvs_core_dev_ops);
- cleanup_sub:
- unregister_pernet_subsys(&ipvs_core_ops);
- cleanup_conn:
- ip_vs_conn_cleanup();
- cleanup_protocol:
- ip_vs_protocol_cleanup();
- ip_vs_control_cleanup();
- exit:
- return ret;
- }
- static void __exit ip_vs_cleanup(void)
- {
- ip_vs_unregister_nl_ioctl();
- unregister_pernet_device(&ipvs_core_dev_ops);
- unregister_pernet_subsys(&ipvs_core_ops); /* free ip_vs struct */
- ip_vs_conn_cleanup();
- ip_vs_protocol_cleanup();
- ip_vs_control_cleanup();
- pr_info("ipvs unloaded.\n");
- }
- module_init(ip_vs_init);
- module_exit(ip_vs_cleanup);
- MODULE_LICENSE("GPL");