diff options
Diffstat (limited to 'net/netfilter/ipvs/ip_vs_core.c')
| -rw-r--r-- | net/netfilter/ipvs/ip_vs_core.c | 2456 |
1 files changed, 2456 insertions, 0 deletions
diff --git a/net/netfilter/ipvs/ip_vs_core.c b/net/netfilter/ipvs/ip_vs_core.c new file mode 100644 index 000000000..b5ae41966 --- /dev/null +++ b/net/netfilter/ipvs/ip_vs_core.c @@ -0,0 +1,2456 @@ +// 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); + +#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); + u64_stats_inc(&s->cnt.inpkts); + u64_stats_add(&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); + u64_stats_inc(&s->cnt.inpkts); + u64_stats_add(&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); + u64_stats_inc(&s->cnt.inpkts); + u64_stats_add(&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); + u64_stats_inc(&s->cnt.outpkts); + u64_stats_add(&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); + u64_stats_inc(&s->cnt.outpkts); + u64_stats_add(&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); + u64_stats_inc(&s->cnt.outpkts); + u64_stats_add(&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); + u64_stats_inc(&s->cnt.conns); + u64_stats_update_end(&s->syncp); + + s = this_cpu_ptr(svc->stats.cpustats); + u64_stats_update_begin(&s->syncp); + u64_stats_inc(&s->cnt.conns); + u64_stats_update_end(&s->syncp); + + s = this_cpu_ptr(ipvs->tot_stats.cpustats); + u64_stats_update_begin(&s->syncp); + u64_stats_inc(&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; +} + +#else + +static int sysctl_snat_reroute(struct netns_ipvs *ipvs) { return 0; } +static int sysctl_nat_icmp_send(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->sk, skb) != 0) + return 1; + } else +#endif + if (!(skb_rtable(skb)->rt_flags & RTCF_LOCAL) && + ip_route_me_harder(ipvs->net, skb->sk, 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 after_nat; + + /* 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; + +after_nat: + /* 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); + 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; + + if (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ) + goto after_nat; + + 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"); + +after_nat: + 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_hook(void *priv, struct sk_buff *skb, const struct nf_hook_state *state) +{ + struct netns_ipvs *ipvs = net_ipvs(state->net); + unsigned int hooknum = state->hook; + struct ip_vs_iphdr iph; + struct ip_vs_protocol *pp; + struct ip_vs_proto_data *pd; + struct ip_vs_conn *cp; + int af = state->pf; + 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)) + 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; + } + } + } + + IP_VS_DBG_PKT(12, af, pp, skb, iph.off, + "ip_vs_out: packet continues traversal as normal"); + return NF_ACCEPT; +} + +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_hook(void *priv, struct sk_buff *skb, const struct nf_hook_state *state) +{ + struct netns_ipvs *ipvs = net_ipvs(state->net); + unsigned int hooknum = state->hook; + struct ip_vs_iphdr iph; + struct ip_vs_protocol *pp; + struct ip_vs_proto_data *pd; + struct ip_vs_conn *cp; + int ret, pkts; + struct sock *sk; + int af = state->pf; + + /* 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); + + if (!iph.fragoffs && is_new_conn(skb, &iph) && cp) { + int conn_reuse_mode = sysctl_conn_reuse_mode(ipvs); + bool old_ct = false, resched = false; + + if (unlikely(sysctl_expire_nodest_conn(ipvs)) && cp->dest && + unlikely(!atomic_read(&cp->dest->weight))) { + resched = true; + old_ct = ip_vs_conn_uses_old_conntrack(cp, skb); + } else if (conn_reuse_mode && + is_new_conn_expected(cp, conn_reuse_mode)) { + old_ct = ip_vs_conn_uses_old_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 = !old_ct; + } + } + + if (resched) { + if (!old_ct) + cp->flags &= ~IP_VS_CONN_F_NFCT; + if (!atomic_read(&cp->n_control)) + ip_vs_conn_expire_now(cp); + __ip_vs_conn_put(cp); + if (old_ct) + return NF_DROP; + cp = NULL; + } + } + + /* Check the server status */ + if (cp && cp->dest && !(cp->dest->flags & IP_VS_DEST_F_AVAILABLE)) { + /* the destination server is not available */ + if (sysctl_expire_nodest_conn(ipvs)) { + bool old_ct = ip_vs_conn_uses_old_conntrack(cp, skb); + + if (!old_ct) + cp->flags &= ~IP_VS_CONN_F_NFCT; + + ip_vs_conn_expire_now(cp); + __ip_vs_conn_put(cp); + if (old_ct) + return NF_DROP; + cp = NULL; + } else { + __ip_vs_conn_put(cp); + return NF_DROP; + } + } + + 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"); + + 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_inc_return(&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; +} + +/* + * 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) +{ + struct netns_ipvs *ipvs = net_ipvs(state->net); + int r; + + /* ipvs enabled in this netns ? */ + if (unlikely(sysctl_backup_only(ipvs) || !ipvs->enable)) + return NF_ACCEPT; + + if (state->pf == NFPROTO_IPV4) { + if (ip_hdr(skb)->protocol != IPPROTO_ICMP) + return NF_ACCEPT; +#ifdef CONFIG_IP_VS_IPV6 + } else { + struct ip_vs_iphdr iphdr; + + ip_vs_fill_iph_skb(AF_INET6, skb, false, &iphdr); + + if (iphdr.protocol != IPPROTO_ICMPV6) + return NF_ACCEPT; + + return ip_vs_in_icmp_v6(ipvs, skb, &r, state->hook, &iphdr); +#endif + } + + return ip_vs_in_icmp(ipvs, skb, &r, state->hook); +} + +static const struct nf_hook_ops ip_vs_ops4[] = { + /* After packet filtering, change source only for VS/NAT */ + { + .hook = ip_vs_out_hook, + .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_in_hook, + .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_out_hook, + .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_in_hook, + .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_out_hook, + .pf = NFPROTO_IPV4, + .hooknum = NF_INET_FORWARD, + .priority = 100, + }, +}; + +#ifdef CONFIG_IP_VS_IPV6 +static const struct nf_hook_ops ip_vs_ops6[] = { + /* After packet filtering, change source only for VS/NAT */ + { + .hook = ip_vs_out_hook, + .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_in_hook, + .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_out_hook, + .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_in_hook, + .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, + .pf = NFPROTO_IPV6, + .hooknum = NF_INET_FORWARD, + .priority = 99, + }, + /* After packet filtering, change source only for VS/NAT */ + { + .hook = ip_vs_out_hook, + .pf = NFPROTO_IPV6, + .hooknum = NF_INET_FORWARD, + .priority = 100, + }, +}; +#endif + +int ip_vs_register_hooks(struct netns_ipvs *ipvs, unsigned int af) +{ + const struct nf_hook_ops *ops; + unsigned int count; + unsigned int afmask; + int ret = 0; + + if (af == AF_INET6) { +#ifdef CONFIG_IP_VS_IPV6 + ops = ip_vs_ops6; + count = ARRAY_SIZE(ip_vs_ops6); + afmask = 2; +#else + return -EINVAL; +#endif + } else { + ops = ip_vs_ops4; + count = ARRAY_SIZE(ip_vs_ops4); + afmask = 1; + } + + if (!(ipvs->hooks_afmask & afmask)) { + ret = nf_register_net_hooks(ipvs->net, ops, count); + if (ret >= 0) + ipvs->hooks_afmask |= afmask; + } + return ret; +} + +void ip_vs_unregister_hooks(struct netns_ipvs *ipvs, unsigned int af) +{ + const struct nf_hook_ops *ops; + unsigned int count; + unsigned int afmask; + + if (af == AF_INET6) { +#ifdef CONFIG_IP_VS_IPV6 + ops = ip_vs_ops6; + count = ARRAY_SIZE(ip_vs_ops6); + afmask = 2; +#else + return; +#endif + } else { + ops = ip_vs_ops4; + count = ARRAY_SIZE(ip_vs_ops4); + afmask = 1; + } + + if (ipvs->hooks_afmask & afmask) { + nf_unregister_net_hooks(ipvs->net, ops, count); + ipvs->hooks_afmask &= ~afmask; + } +} + +/* + * 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 registered */ + 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 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); + ip_vs_unregister_hooks(ipvs, AF_INET); + ip_vs_unregister_hooks(ipvs, AF_INET6); + 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 = { + .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"); |