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-rw-r--r--net/ipv4/ipvs/ip_vs_core.c1125
1 files changed, 0 insertions, 1125 deletions
diff --git a/net/ipv4/ipvs/ip_vs_core.c b/net/ipv4/ipvs/ip_vs_core.c
deleted file mode 100644
index a7879eafc3b5..000000000000
--- a/net/ipv4/ipvs/ip_vs_core.c
+++ /dev/null
@@ -1,1125 +0,0 @@
-/*
- * 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>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- *
- * 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
- *
- */
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/ip.h>
-#include <linux/tcp.h>
-#include <linux/icmp.h>
-
-#include <net/ip.h>
-#include <net/tcp.h>
-#include <net/udp.h>
-#include <net/icmp.h> /* for icmp_send */
-#include <net/route.h>
-
-#include <linux/netfilter.h>
-#include <linux/netfilter_ipv4.h>
-
-#include <net/ip_vs.h>
-
-
-EXPORT_SYMBOL(register_ip_vs_scheduler);
-EXPORT_SYMBOL(unregister_ip_vs_scheduler);
-EXPORT_SYMBOL(ip_vs_skb_replace);
-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
-
-
-/* ID used in ICMP lookups */
-#define icmp_id(icmph) (((icmph)->un).echo.id)
-
-const char *ip_vs_proto_name(unsigned proto)
-{
- static char buf[20];
-
- switch (proto) {
- case IPPROTO_IP:
- return "IP";
- case IPPROTO_UDP:
- return "UDP";
- case IPPROTO_TCP:
- return "TCP";
- case IPPROTO_ICMP:
- return "ICMP";
- default:
- sprintf(buf, "IP_%d", 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;
- if (dest && (dest->flags & IP_VS_DEST_F_AVAILABLE)) {
- spin_lock(&dest->stats.lock);
- dest->stats.inpkts++;
- dest->stats.inbytes += skb->len;
- spin_unlock(&dest->stats.lock);
-
- spin_lock(&dest->svc->stats.lock);
- dest->svc->stats.inpkts++;
- dest->svc->stats.inbytes += skb->len;
- spin_unlock(&dest->svc->stats.lock);
-
- spin_lock(&ip_vs_stats.lock);
- ip_vs_stats.inpkts++;
- ip_vs_stats.inbytes += skb->len;
- spin_unlock(&ip_vs_stats.lock);
- }
-}
-
-
-static inline void
-ip_vs_out_stats(struct ip_vs_conn *cp, struct sk_buff *skb)
-{
- struct ip_vs_dest *dest = cp->dest;
- if (dest && (dest->flags & IP_VS_DEST_F_AVAILABLE)) {
- spin_lock(&dest->stats.lock);
- dest->stats.outpkts++;
- dest->stats.outbytes += skb->len;
- spin_unlock(&dest->stats.lock);
-
- spin_lock(&dest->svc->stats.lock);
- dest->svc->stats.outpkts++;
- dest->svc->stats.outbytes += skb->len;
- spin_unlock(&dest->svc->stats.lock);
-
- spin_lock(&ip_vs_stats.lock);
- ip_vs_stats.outpkts++;
- ip_vs_stats.outbytes += skb->len;
- spin_unlock(&ip_vs_stats.lock);
- }
-}
-
-
-static inline void
-ip_vs_conn_stats(struct ip_vs_conn *cp, struct ip_vs_service *svc)
-{
- spin_lock(&cp->dest->stats.lock);
- cp->dest->stats.conns++;
- spin_unlock(&cp->dest->stats.lock);
-
- spin_lock(&svc->stats.lock);
- svc->stats.conns++;
- spin_unlock(&svc->stats.lock);
-
- spin_lock(&ip_vs_stats.lock);
- ip_vs_stats.conns++;
- spin_unlock(&ip_vs_stats.lock);
-}
-
-
-static inline int
-ip_vs_set_state(struct ip_vs_conn *cp, int direction,
- const struct sk_buff *skb,
- struct ip_vs_protocol *pp)
-{
- if (unlikely(!pp->state_transition))
- return 0;
- return pp->state_transition(cp, direction, skb, pp);
-}
-
-
-/*
- * 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,
- const struct sk_buff *skb,
- __be16 ports[2])
-{
- struct ip_vs_conn *cp = NULL;
- struct iphdr *iph = ip_hdr(skb);
- struct ip_vs_dest *dest;
- struct ip_vs_conn *ct;
- __be16 dport; /* destination port to forward */
- __be32 snet; /* source network of the client, after masking */
-
- /* Mask saddr with the netmask to adjust template granularity */
- snet = iph->saddr & svc->netmask;
-
- IP_VS_DBG(6, "p-schedule: src %u.%u.%u.%u:%u dest %u.%u.%u.%u:%u "
- "mnet %u.%u.%u.%u\n",
- NIPQUAD(iph->saddr), ntohs(ports[0]),
- NIPQUAD(iph->daddr), ntohs(ports[1]),
- NIPQUAD(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.
- */
- if (ports[1] == svc->port) {
- /* Check if a template already exists */
- if (svc->port != FTPPORT)
- ct = ip_vs_ct_in_get(iph->protocol, snet, 0,
- iph->daddr, ports[1]);
- else
- ct = ip_vs_ct_in_get(iph->protocol, snet, 0,
- iph->daddr, 0);
-
- if (!ct || !ip_vs_check_template(ct)) {
- /*
- * No template found or the dest of the connection
- * template is not available.
- */
- dest = svc->scheduler->schedule(svc, skb);
- if (dest == NULL) {
- IP_VS_DBG(1, "p-schedule: no dest found.\n");
- return NULL;
- }
-
- /*
- * Create a template like <protocol,caddr,0,
- * vaddr,vport,daddr,dport> for non-ftp service,
- * and <protocol,caddr,0,vaddr,0,daddr,0>
- * for ftp service.
- */
- if (svc->port != FTPPORT)
- ct = ip_vs_conn_new(iph->protocol,
- snet, 0,
- iph->daddr,
- ports[1],
- dest->addr, dest->port,
- IP_VS_CONN_F_TEMPLATE,
- dest);
- else
- ct = ip_vs_conn_new(iph->protocol,
- snet, 0,
- iph->daddr, 0,
- dest->addr, 0,
- IP_VS_CONN_F_TEMPLATE,
- dest);
- if (ct == NULL)
- return NULL;
-
- ct->timeout = svc->timeout;
- } else {
- /* set destination with the found template */
- dest = ct->dest;
- }
- dport = dest->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)
- ct = ip_vs_ct_in_get(IPPROTO_IP, snet, 0,
- htonl(svc->fwmark), 0);
- else
- ct = ip_vs_ct_in_get(iph->protocol, snet, 0,
- iph->daddr, 0);
-
- if (!ct || !ip_vs_check_template(ct)) {
- /*
- * If it is not persistent port zero, return NULL,
- * otherwise create a connection template.
- */
- if (svc->port)
- return NULL;
-
- dest = svc->scheduler->schedule(svc, skb);
- if (dest == NULL) {
- IP_VS_DBG(1, "p-schedule: no dest found.\n");
- return NULL;
- }
-
- /*
- * Create a template according to the service
- */
- if (svc->fwmark)
- ct = ip_vs_conn_new(IPPROTO_IP,
- snet, 0,
- htonl(svc->fwmark), 0,
- dest->addr, 0,
- IP_VS_CONN_F_TEMPLATE,
- dest);
- else
- ct = ip_vs_conn_new(iph->protocol,
- snet, 0,
- iph->daddr, 0,
- dest->addr, 0,
- IP_VS_CONN_F_TEMPLATE,
- dest);
- if (ct == NULL)
- return NULL;
-
- ct->timeout = svc->timeout;
- } else {
- /* set destination with the found template */
- dest = ct->dest;
- }
- dport = ports[1];
- }
-
- /*
- * Create a new connection according to the template
- */
- cp = ip_vs_conn_new(iph->protocol,
- iph->saddr, ports[0],
- iph->daddr, ports[1],
- dest->addr, dport,
- 0,
- dest);
- if (cp == NULL) {
- ip_vs_conn_put(ct);
- 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
- */
-struct ip_vs_conn *
-ip_vs_schedule(struct ip_vs_service *svc, const struct sk_buff *skb)
-{
- struct ip_vs_conn *cp = NULL;
- struct iphdr *iph = ip_hdr(skb);
- struct ip_vs_dest *dest;
- __be16 _ports[2], *pptr;
-
- pptr = skb_header_pointer(skb, iph->ihl*4,
- sizeof(_ports), _ports);
- if (pptr == NULL)
- return NULL;
-
- /*
- * Persistent service
- */
- if (svc->flags & IP_VS_SVC_F_PERSISTENT)
- return ip_vs_sched_persist(svc, skb, pptr);
-
- /*
- * Non-persistent service
- */
- if (!svc->fwmark && pptr[1] != svc->port) {
- if (!svc->port)
- IP_VS_ERR("Schedule: port zero only supported "
- "in persistent services, "
- "check your ipvs configuration\n");
- return NULL;
- }
-
- dest = svc->scheduler->schedule(svc, skb);
- if (dest == NULL) {
- IP_VS_DBG(1, "Schedule: no dest found.\n");
- return NULL;
- }
-
- /*
- * Create a connection entry.
- */
- cp = ip_vs_conn_new(iph->protocol,
- iph->saddr, pptr[0],
- iph->daddr, pptr[1],
- dest->addr, dest->port?dest->port:pptr[1],
- 0,
- dest);
- if (cp == NULL)
- return NULL;
-
- IP_VS_DBG(6, "Schedule fwd:%c c:%u.%u.%u.%u:%u v:%u.%u.%u.%u:%u "
- "d:%u.%u.%u.%u:%u conn->flags:%X conn->refcnt:%d\n",
- ip_vs_fwd_tag(cp),
- NIPQUAD(cp->caddr), ntohs(cp->cport),
- NIPQUAD(cp->vaddr), ntohs(cp->vport),
- NIPQUAD(cp->daddr), ntohs(cp->dport),
- cp->flags, atomic_read(&cp->refcnt));
-
- ip_vs_conn_stats(cp, svc);
- return cp;
-}
-
-
-/*
- * 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_protocol *pp)
-{
- __be16 _ports[2], *pptr;
- struct iphdr *iph = ip_hdr(skb);
-
- pptr = skb_header_pointer(skb, iph->ihl*4,
- sizeof(_ports), _ports);
- if (pptr == NULL) {
- ip_vs_service_put(svc);
- return NF_DROP;
- }
-
- /* if it is fwmark-based service, the cache_bypass sysctl is up
- and the destination is RTN_UNICAST (and not local), then create
- a cache_bypass connection entry */
- if (sysctl_ip_vs_cache_bypass && svc->fwmark
- && (inet_addr_type(&init_net, iph->daddr) == RTN_UNICAST)) {
- int ret, cs;
- struct ip_vs_conn *cp;
-
- ip_vs_service_put(svc);
-
- /* create a new connection entry */
- IP_VS_DBG(6, "ip_vs_leave: create a cache_bypass entry\n");
- cp = ip_vs_conn_new(iph->protocol,
- iph->saddr, pptr[0],
- iph->daddr, pptr[1],
- 0, 0,
- IP_VS_CONN_F_BYPASS,
- NULL);
- if (cp == NULL)
- return NF_DROP;
-
- /* statistics */
- ip_vs_in_stats(cp, skb);
-
- /* set state */
- cs = ip_vs_set_state(cp, IP_VS_DIR_INPUT, skb, pp);
-
- /* transmit the first SYN packet */
- ret = cp->packet_xmit(skb, cp, pp);
- /* do not touch skb anymore */
-
- 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) && (pptr[1] != FTPPORT)) {
- ip_vs_service_put(svc);
- return NF_ACCEPT;
- }
-
- ip_vs_service_put(svc);
-
- /*
- * 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
- */
- icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
- return NF_DROP;
-}
-
-
-/*
- * It is hooked before NF_IP_PRI_NAT_SRC at the NF_INET_POST_ROUTING
- * chain, and is used for VS/NAT.
- * It detects packets for VS/NAT connections and sends the packets
- * immediately. This can avoid that iptable_nat mangles the packets
- * for VS/NAT.
- */
-static unsigned int ip_vs_post_routing(unsigned int hooknum,
- struct sk_buff *skb,
- const struct net_device *in,
- const struct net_device *out,
- int (*okfn)(struct sk_buff *))
-{
- if (!skb->ipvs_property)
- return NF_ACCEPT;
- /* The packet was sent from IPVS, exit this chain */
- return NF_STOP;
-}
-
-__sum16 ip_vs_checksum_complete(struct sk_buff *skb, int offset)
-{
- return csum_fold(skb_checksum(skb, offset, skb->len - offset, 0));
-}
-
-static inline int ip_vs_gather_frags(struct sk_buff *skb, u_int32_t user)
-{
- int err = ip_defrag(skb, user);
-
- if (!err)
- ip_send_check(ip_hdr(skb));
-
- return err;
-}
-
-/*
- * 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_send_check(iph);
- ciph->daddr = cp->vaddr;
- ip_send_check(ciph);
- } else {
- iph->daddr = cp->daddr;
- ip_send_check(iph);
- ciph->saddr = cp->daddr;
- ip_send_check(ciph);
- }
-
- /* the TCP/UDP port */
- if (IPPROTO_TCP == ciph->protocol || IPPROTO_UDP == 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, pp, skb, (void *)ciph - (void *)iph,
- "Forwarding altered outgoing ICMP");
- else
- IP_VS_DBG_PKT(11, pp, skb, (void *)ciph - (void *)iph,
- "Forwarding altered incoming ICMP");
-}
-
-/*
- * Handle ICMP messages in the inside-to-outside direction (outgoing).
- * 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.
- * (Only used in VS/NAT)
- */
-static int ip_vs_out_icmp(struct sk_buff *skb, int *related)
-{
- struct iphdr *iph;
- struct icmphdr _icmph, *ic;
- struct iphdr _ciph, *cih; /* The ip header contained within the ICMP */
- struct ip_vs_conn *cp;
- struct ip_vs_protocol *pp;
- unsigned int offset, ihl, verdict;
-
- *related = 1;
-
- /* reassemble IP fragments */
- if (ip_hdr(skb)->frag_off & htons(IP_MF | IP_OFFSET)) {
- if (ip_vs_gather_frags(skb, IP_DEFRAG_VS_OUT))
- 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) %u.%u.%u.%u->%u.%u.%u.%u\n",
- ic->type, ntohs(icmp_id(ic)),
- NIPQUAD(iph->saddr), NIPQUAD(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, pp, skb, offset, "Checking outgoing ICMP for");
-
- offset += cih->ihl * 4;
-
- /* The embedded headers contain source and dest in reverse order */
- cp = pp->conn_out_get(skb, pp, cih, offset, 1);
- if (!cp)
- return NF_ACCEPT;
-
- verdict = NF_DROP;
-
- if (IP_VS_FWD_METHOD(cp) != 0) {
- IP_VS_ERR("shouldn't reach here, because the box is on the "
- "half connection in the tun/dr module.\n");
- }
-
- /* Ensure the checksum is correct */
- if (!skb_csum_unnecessary(skb) && ip_vs_checksum_complete(skb, ihl)) {
- /* Failed checksum! */
- IP_VS_DBG(1, "Forward ICMP: failed checksum from %d.%d.%d.%d!\n",
- NIPQUAD(iph->saddr));
- goto out;
- }
-
- if (IPPROTO_TCP == cih->protocol || IPPROTO_UDP == cih->protocol)
- offset += 2 * sizeof(__u16);
- if (!skb_make_writable(skb, offset))
- goto out;
-
- ip_vs_nat_icmp(skb, pp, cp, 1);
-
- /* do the statistics and put it back */
- ip_vs_out_stats(cp, skb);
-
- skb->ipvs_property = 1;
- verdict = NF_ACCEPT;
-
- out:
- __ip_vs_conn_put(cp);
-
- return verdict;
-}
-
-static inline int is_tcp_reset(const struct sk_buff *skb)
-{
- struct tcphdr _tcph, *th;
-
- th = skb_header_pointer(skb, ip_hdrlen(skb), sizeof(_tcph), &_tcph);
- if (th == NULL)
- return 0;
- return th->rst;
-}
-
-/*
- * It is hooked at the NF_INET_FORWARD chain, used only for VS/NAT.
- * Check if outgoing packet belongs to the established ip_vs_conn,
- * rewrite addresses of the packet and send it on its way...
- */
-static unsigned int
-ip_vs_out(unsigned int hooknum, struct sk_buff *skb,
- const struct net_device *in, const struct net_device *out,
- int (*okfn)(struct sk_buff *))
-{
- struct iphdr *iph;
- struct ip_vs_protocol *pp;
- struct ip_vs_conn *cp;
- int ihl;
-
- EnterFunction(11);
-
- if (skb->ipvs_property)
- return NF_ACCEPT;
-
- iph = ip_hdr(skb);
- if (unlikely(iph->protocol == IPPROTO_ICMP)) {
- int related, verdict = ip_vs_out_icmp(skb, &related);
-
- if (related)
- return verdict;
- iph = ip_hdr(skb);
- }
-
- pp = ip_vs_proto_get(iph->protocol);
- if (unlikely(!pp))
- return NF_ACCEPT;
-
- /* reassemble IP fragments */
- if (unlikely(iph->frag_off & htons(IP_MF|IP_OFFSET) &&
- !pp->dont_defrag)) {
- if (ip_vs_gather_frags(skb, IP_DEFRAG_VS_OUT))
- return NF_STOLEN;
- iph = ip_hdr(skb);
- }
-
- ihl = iph->ihl << 2;
-
- /*
- * Check if the packet belongs to an existing entry
- */
- cp = pp->conn_out_get(skb, pp, iph, ihl, 0);
-
- if (unlikely(!cp)) {
- if (sysctl_ip_vs_nat_icmp_send &&
- (pp->protocol == IPPROTO_TCP ||
- pp->protocol == IPPROTO_UDP)) {
- __be16 _ports[2], *pptr;
-
- pptr = skb_header_pointer(skb, ihl,
- sizeof(_ports), _ports);
- if (pptr == NULL)
- return NF_ACCEPT; /* Not for me */
- if (ip_vs_lookup_real_service(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
- || !is_tcp_reset(skb)) {
- icmp_send(skb,ICMP_DEST_UNREACH,
- ICMP_PORT_UNREACH, 0);
- return NF_DROP;
- }
- }
- }
- IP_VS_DBG_PKT(12, pp, skb, 0,
- "packet continues traversal as normal");
- return NF_ACCEPT;
- }
-
- IP_VS_DBG_PKT(11, pp, skb, 0, "Outgoing packet");
-
- if (!skb_make_writable(skb, ihl))
- goto drop;
-
- /* mangle the packet */
- if (pp->snat_handler && !pp->snat_handler(skb, pp, cp))
- goto drop;
- ip_hdr(skb)->saddr = cp->vaddr;
- ip_send_check(ip_hdr(skb));
-
- /* 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_route_me_harder(skb, RTN_LOCAL) != 0)
- goto drop;
-
- IP_VS_DBG_PKT(10, pp, skb, 0, "After SNAT");
-
- ip_vs_out_stats(cp, skb);
- ip_vs_set_state(cp, IP_VS_DIR_OUTPUT, skb, pp);
- ip_vs_conn_put(cp);
-
- skb->ipvs_property = 1;
-
- LeaveFunction(11);
- return NF_ACCEPT;
-
- drop:
- ip_vs_conn_put(cp);
- kfree_skb(skb);
- return NF_STOLEN;
-}
-
-
-/*
- * 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 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_conn *cp;
- struct ip_vs_protocol *pp;
- unsigned int offset, ihl, verdict;
-
- *related = 1;
-
- /* reassemble IP fragments */
- if (ip_hdr(skb)->frag_off & htons(IP_MF | IP_OFFSET)) {
- if (ip_vs_gather_frags(skb, hooknum == NF_INET_LOCAL_IN ?
- IP_DEFRAG_VS_IN : IP_DEFRAG_VS_FWD))
- 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) %u.%u.%u.%u->%u.%u.%u.%u\n",
- ic->type, ntohs(icmp_id(ic)),
- NIPQUAD(iph->saddr), NIPQUAD(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, pp, skb, offset, "Checking incoming ICMP for");
-
- offset += cih->ihl * 4;
-
- /* The embedded headers contain source and dest in reverse order */
- cp = pp->conn_in_get(skb, pp, cih, offset, 1);
- if (!cp)
- return NF_ACCEPT;
-
- 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 %d.%d.%d.%d!\n",
- NIPQUAD(iph->saddr));
- goto out;
- }
-
- /* do the statistics and put it back */
- ip_vs_in_stats(cp, skb);
- if (IPPROTO_TCP == cih->protocol || IPPROTO_UDP == cih->protocol)
- offset += 2 * sizeof(__u16);
- verdict = ip_vs_icmp_xmit(skb, cp, pp, offset);
- /* do not touch skb anymore */
-
- out:
- __ip_vs_conn_put(cp);
-
- return verdict;
-}
-
-/*
- * Check if it's for virtual services, look it up,
- * and send it on its way...
- */
-static unsigned int
-ip_vs_in(unsigned int hooknum, struct sk_buff *skb,
- const struct net_device *in, const struct net_device *out,
- int (*okfn)(struct sk_buff *))
-{
- struct iphdr *iph;
- struct ip_vs_protocol *pp;
- struct ip_vs_conn *cp;
- int ret, restart;
- int ihl;
-
- /*
- * Big tappo: only PACKET_HOST (neither loopback nor mcasts)
- * ... don't know why 1st test DOES NOT include 2nd (?)
- */
- if (unlikely(skb->pkt_type != PACKET_HOST
- || skb->dev->flags & IFF_LOOPBACK || skb->sk)) {
- IP_VS_DBG(12, "packet type=%d proto=%d daddr=%d.%d.%d.%d ignored\n",
- skb->pkt_type,
- ip_hdr(skb)->protocol,
- NIPQUAD(ip_hdr(skb)->daddr));
- return NF_ACCEPT;
- }
-
- iph = ip_hdr(skb);
- if (unlikely(iph->protocol == IPPROTO_ICMP)) {
- int related, verdict = ip_vs_in_icmp(skb, &related, hooknum);
-
- if (related)
- return verdict;
- iph = ip_hdr(skb);
- }
-
- /* Protocol supported? */
- pp = ip_vs_proto_get(iph->protocol);
- if (unlikely(!pp))
- return NF_ACCEPT;
-
- ihl = iph->ihl << 2;
-
- /*
- * Check if the packet belongs to an existing connection entry
- */
- cp = pp->conn_in_get(skb, pp, iph, ihl, 0);
-
- if (unlikely(!cp)) {
- int v;
-
- if (!pp->conn_schedule(skb, pp, &v, &cp))
- return v;
- }
-
- if (unlikely(!cp)) {
- /* sorry, all this trouble for a no-hit :) */
- IP_VS_DBG_PKT(12, pp, skb, 0,
- "packet continues traversal as normal");
- return NF_ACCEPT;
- }
-
- IP_VS_DBG_PKT(11, pp, skb, 0, "Incoming packet");
-
- /* Check the server status */
- if (cp->dest && !(cp->dest->flags & IP_VS_DEST_F_AVAILABLE)) {
- /* the destination server is not available */
-
- if (sysctl_ip_vs_expire_nodest_conn) {
- /* try to expire the connection immediately */
- ip_vs_conn_expire_now(cp);
- }
- /* don't restart its timer, and silently
- drop the packet. */
- __ip_vs_conn_put(cp);
- return NF_DROP;
- }
-
- ip_vs_in_stats(cp, skb);
- restart = ip_vs_set_state(cp, IP_VS_DIR_INPUT, skb, pp);
- if (cp->packet_xmit)
- ret = cp->packet_xmit(skb, cp, pp);
- /* 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
- */
- atomic_inc(&cp->in_pkts);
- if ((ip_vs_sync_state & IP_VS_STATE_MASTER) &&
- (((cp->protocol != IPPROTO_TCP ||
- cp->state == IP_VS_TCP_S_ESTABLISHED) &&
- (atomic_read(&cp->in_pkts) % sysctl_ip_vs_sync_threshold[1]
- == sysctl_ip_vs_sync_threshold[0])) ||
- ((cp->protocol == IPPROTO_TCP) && (cp->old_state != cp->state) &&
- ((cp->state == IP_VS_TCP_S_FIN_WAIT) ||
- (cp->state == IP_VS_TCP_S_CLOSE_WAIT) ||
- (cp->state == IP_VS_TCP_S_TIME_WAIT)))))
- ip_vs_sync_conn(cp);
- cp->old_state = cp->state;
-
- 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(unsigned int hooknum, struct sk_buff *skb,
- const struct net_device *in, const struct net_device *out,
- int (*okfn)(struct sk_buff *))
-{
- int r;
-
- if (ip_hdr(skb)->protocol != IPPROTO_ICMP)
- return NF_ACCEPT;
-
- return ip_vs_in_icmp(skb, &r, hooknum);
-}
-
-
-static struct nf_hook_ops ip_vs_ops[] __read_mostly = {
- /* 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,
- .owner = THIS_MODULE,
- .pf = PF_INET,
- .hooknum = NF_INET_LOCAL_IN,
- .priority = 100,
- },
- /* After packet filtering, change source only for VS/NAT */
- {
- .hook = ip_vs_out,
- .owner = THIS_MODULE,
- .pf = PF_INET,
- .hooknum = NF_INET_FORWARD,
- .priority = 100,
- },
- /* 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,
- .owner = THIS_MODULE,
- .pf = PF_INET,
- .hooknum = NF_INET_FORWARD,
- .priority = 99,
- },
- /* Before the netfilter connection tracking, exit from POST_ROUTING */
- {
- .hook = ip_vs_post_routing,
- .owner = THIS_MODULE,
- .pf = PF_INET,
- .hooknum = NF_INET_POST_ROUTING,
- .priority = NF_IP_PRI_NAT_SRC-1,
- },
-};
-
-
-/*
- * Initialize IP Virtual Server
- */
-static int __init ip_vs_init(void)
-{
- int ret;
-
- ret = ip_vs_control_init();
- if (ret < 0) {
- IP_VS_ERR("can't setup control.\n");
- goto cleanup_nothing;
- }
-
- ip_vs_protocol_init();
-
- ret = ip_vs_app_init();
- if (ret < 0) {
- IP_VS_ERR("can't setup application helper.\n");
- goto cleanup_protocol;
- }
-
- ret = ip_vs_conn_init();
- if (ret < 0) {
- IP_VS_ERR("can't setup connection table.\n");
- goto cleanup_app;
- }
-
- ret = nf_register_hooks(ip_vs_ops, ARRAY_SIZE(ip_vs_ops));
- if (ret < 0) {
- IP_VS_ERR("can't register hooks.\n");
- goto cleanup_conn;
- }
-
- IP_VS_INFO("ipvs loaded.\n");
- return ret;
-
- cleanup_conn:
- ip_vs_conn_cleanup();
- cleanup_app:
- ip_vs_app_cleanup();
- cleanup_protocol:
- ip_vs_protocol_cleanup();
- ip_vs_control_cleanup();
- cleanup_nothing:
- return ret;
-}
-
-static void __exit ip_vs_cleanup(void)
-{
- nf_unregister_hooks(ip_vs_ops, ARRAY_SIZE(ip_vs_ops));
- ip_vs_conn_cleanup();
- ip_vs_app_cleanup();
- ip_vs_protocol_cleanup();
- ip_vs_control_cleanup();
- IP_VS_INFO("ipvs unloaded.\n");
-}
-
-module_init(ip_vs_init);
-module_exit(ip_vs_cleanup);
-MODULE_LICENSE("GPL");