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gfiber / kernel / skids / ea0ece8e0fec89cd0c162d6962ed11b5f1115d70 / . / net / netfilter / ipvs / ip_vs_core.c
blob: 1cd6e3fd058b71b6f49a51589a52451944e177e0 [file] [log] [blame]
/*
* 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
*
*/
#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/route.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv4.h>
#ifdef CONFIG_IP_VS_IPV6
#include <net/ipv6.h>
#include <linux/netfilter_ipv6.h>
#endif
#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)
#define icmpv6_id(icmph) (icmph->icmp6_dataun.u_echo.identifier)
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_SCTP:
return "SCTP";
case IPPROTO_ICMP:
return "ICMP";
#ifdef CONFIG_IP_VS_IPV6
case IPPROTO_ICMPV6:
return "ICMPv6";
#endif
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.ustats.inpkts++;
dest->stats.ustats.inbytes += skb->len;
spin_unlock(&dest->stats.lock);
spin_lock(&dest->svc->stats.lock);
dest->svc->stats.ustats.inpkts++;
dest->svc->stats.ustats.inbytes += skb->len;
spin_unlock(&dest->svc->stats.lock);
spin_lock(&ip_vs_stats.lock);
ip_vs_stats.ustats.inpkts++;
ip_vs_stats.ustats.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.ustats.outpkts++;
dest->stats.ustats.outbytes += skb->len;
spin_unlock(&dest->stats.lock);
spin_lock(&dest->svc->stats.lock);
dest->svc->stats.ustats.outpkts++;
dest->svc->stats.ustats.outbytes += skb->len;
spin_unlock(&dest->svc->stats.lock);
spin_lock(&ip_vs_stats.lock);
ip_vs_stats.ustats.outpkts++;
ip_vs_stats.ustats.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.ustats.conns++;
spin_unlock(&cp->dest->stats.lock);
spin_lock(&svc->stats.lock);
svc->stats.ustats.conns++;
spin_unlock(&svc->stats.lock);
spin_lock(&ip_vs_stats.lock);
ip_vs_stats.ustats.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 ip_vs_iphdr iph;
struct ip_vs_dest *dest;
struct ip_vs_conn *ct;
__be16 dport; /* destination port to forward */
union nf_inet_addr snet; /* source network of the client,
after masking */
ip_vs_fill_iphdr(svc->af, skb_network_header(skb), &iph);
/* Mask saddr with the netmask to adjust template granularity */
#ifdef CONFIG_IP_VS_IPV6
if (svc->af == AF_INET6)
ipv6_addr_prefix(&snet.in6, &iph.saddr.in6, svc->netmask);
else
#endif
snet.ip = iph.saddr.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, &iph.saddr), ntohs(ports[0]),
IP_VS_DBG_ADDR(svc->af, &iph.daddr), ntohs(ports[1]),
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.
*/
if (ports[1] == svc->port) {
/* Check if a template already exists */
if (svc->port != FTPPORT)
ct = ip_vs_ct_in_get(svc->af, iph.protocol, &snet, 0,
&iph.daddr, ports[1]);
else
ct = ip_vs_ct_in_get(svc->af, 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(svc->af, iph.protocol,
&snet, 0,
&iph.daddr,
ports[1],
&dest->addr, dest->port,
IP_VS_CONN_F_TEMPLATE,
dest);
else
ct = ip_vs_conn_new(svc->af, 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) {
union nf_inet_addr fwmark = {
.ip = htonl(svc->fwmark)
};
ct = ip_vs_ct_in_get(svc->af, IPPROTO_IP, &snet, 0,
&fwmark, 0);
} else
ct = ip_vs_ct_in_get(svc->af, 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) {
union nf_inet_addr fwmark = {
.ip = htonl(svc->fwmark)
};
ct = ip_vs_conn_new(svc->af, IPPROTO_IP,
&snet, 0,
&fwmark, 0,
&dest->addr, 0,
IP_VS_CONN_F_TEMPLATE,
dest);
} else
ct = ip_vs_conn_new(svc->af, 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(svc->af, 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 ip_vs_iphdr iph;
struct ip_vs_dest *dest;
__be16 _ports[2], *pptr;
ip_vs_fill_iphdr(svc->af, skb_network_header(skb), &iph);
pptr = skb_header_pointer(skb, iph.len, 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)
pr_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(svc->af, 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_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(svc->af, &cp->caddr), ntohs(cp->cport),
IP_VS_DBG_ADDR(svc->af, &cp->vaddr), ntohs(cp->vport),
IP_VS_DBG_ADDR(svc->af, &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 ip_vs_iphdr iph;
int unicast;
ip_vs_fill_iphdr(svc->af, skb_network_header(skb), &iph);
pptr = skb_header_pointer(skb, iph.len, sizeof(_ports), _ports);
if (pptr == NULL) {
ip_vs_service_put(svc);
return NF_DROP;
}
#ifdef CONFIG_IP_VS_IPV6
if (svc->af == AF_INET6)
unicast = ipv6_addr_type(&iph.daddr.in6) & IPV6_ADDR_UNICAST;
else
#endif
unicast = (inet_addr_type(&init_net, iph.daddr.ip) == RTN_UNICAST);
/* 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_ip_vs_cache_bypass && svc->fwmark && unicast) {
int ret, cs;
struct ip_vs_conn *cp;
union nf_inet_addr daddr = { .all = { 0, 0, 0, 0 } };
ip_vs_service_put(svc);
/* create a new connection entry */
IP_VS_DBG(6, "%s(): create a cache_bypass entry\n", __func__);
cp = ip_vs_conn_new(svc->af, iph.protocol,
&iph.saddr, pptr[0],
&iph.daddr, pptr[1],
&daddr, 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
*/
#ifdef CONFIG_IP_VS_IPV6
if (svc->af == AF_INET6)
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;
}
/*
* 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;
}
#ifdef CONFIG_IP_VS_IPV6
static inline int ip_vs_gather_frags_v6(struct sk_buff *skb, u_int32_t user)
{
/* TODO IPv6: Find out what to do here for IPv6 */
return 0;
}
#endif
/*
* 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, 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");
}
#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 = sizeof(struct ipv6hdr);
struct icmp6hdr *icmph = (struct icmp6hdr *)(skb_network_header(skb) +
icmp_offset);
struct ipv6hdr *ciph = (struct ipv6hdr *)(icmph + 1);
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 (IPPROTO_TCP == ciph->nexthdr || IPPROTO_UDP == ciph->nexthdr ||
IPPROTO_SCTP == ciph->nexthdr) {
__be16 *ports = (void *)ciph + sizeof(struct ipv6hdr);
if (inout)
ports[1] = cp->vport;
else
ports[0] = cp->dport;
}
/* And finally the ICMP checksum */
icmph->icmp6_cksum = 0;
/* TODO IPv6: is this correct for ICMPv6? */
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 ICMPv6");
else
IP_VS_DBG_PKT(11, pp, skb, (void *)ciph - (void *)iph,
"Forwarding altered incoming ICMPv6");
}
#endif
/* Handle relevant response ICMP messages - forward to the right
* destination host. Used for NAT and local client.
*/
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 verdict = NF_DROP;
if (IP_VS_FWD_METHOD(cp) != 0) {
pr_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_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_make_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);
/* 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;
}
/*
* 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 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_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_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) %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, pp, skb, offset, "Checking outgoing ICMP for");
offset += cih->ihl * 4;
ip_vs_fill_iphdr(AF_INET, cih, &ciph);
/* The embedded headers contain source and dest in reverse order */
cp = pp->conn_out_get(AF_INET, skb, pp, &ciph, offset, 1);
if (!cp)
return NF_ACCEPT;
snet.ip = iph->saddr;
return handle_response_icmp(AF_INET, skb, &snet, cih->protocol, cp,
pp, offset, ihl);
}
#ifdef CONFIG_IP_VS_IPV6
static int ip_vs_out_icmp_v6(struct sk_buff *skb, int *related)
{
struct ipv6hdr *iph;
struct icmp6hdr _icmph, *ic;
struct ipv6hdr _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;
union nf_inet_addr snet;
*related = 1;
/* reassemble IP fragments */
if (ipv6_hdr(skb)->nexthdr == IPPROTO_FRAGMENT) {
if (ip_vs_gather_frags_v6(skb, IP_DEFRAG_VS_OUT))
return NF_STOLEN;
}
iph = ipv6_hdr(skb);
offset = sizeof(struct ipv6hdr);
ic = skb_header_pointer(skb, offset, sizeof(_icmph), &_icmph);
if (ic == NULL)
return NF_DROP;
IP_VS_DBG(12, "Outgoing ICMPv6 (%d,%d) %pI6->%pI6\n",
ic->icmp6_type, ntohs(icmpv6_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->icmp6_type != ICMPV6_DEST_UNREACH) &&
(ic->icmp6_type != ICMPV6_PKT_TOOBIG) &&
(ic->icmp6_type != ICMPV6_TIME_EXCEED)) {
*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->nexthdr);
if (!pp)
return NF_ACCEPT;
/* Is the embedded protocol header present? */
/* TODO: we don't support fragmentation at the moment anyways */
if (unlikely(cih->nexthdr == IPPROTO_FRAGMENT && pp->dont_defrag))
return NF_ACCEPT;
IP_VS_DBG_PKT(11, pp, skb, offset, "Checking outgoing ICMPv6 for");
offset += sizeof(struct ipv6hdr);
ip_vs_fill_iphdr(AF_INET6, cih, &ciph);
/* The embedded headers contain source and dest in reverse order */
cp = pp->conn_out_get(AF_INET6, skb, pp, &ciph, offset, 1);
if (!cp)
return NF_ACCEPT;
ipv6_addr_copy(&snet.in6, &iph->saddr);
return handle_response_icmp(AF_INET6, skb, &snet, cih->nexthdr, cp,
pp, offset, sizeof(struct ipv6hdr));
}
#endif
/*
* Check if sctp chunc is ABORT chunk
*/
static inline int is_sctp_abort(const struct sk_buff *skb, int nh_len)
{
sctp_chunkhdr_t *sch, schunk;
sch = skb_header_pointer(skb, nh_len + sizeof(sctp_sctphdr_t),
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;
}
/* Handle response packets: rewrite addresses and send away...
* Used for NAT and local client.
*/
static unsigned int
handle_response(int af, struct sk_buff *skb, struct ip_vs_protocol *pp,
struct ip_vs_conn *cp, int ihl)
{
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;
#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));
}
/* 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.
*/
#ifdef CONFIG_IP_VS_IPV6
if (af == AF_INET6) {
if (ip6_route_me_harder(skb) != 0)
goto drop;
} else
#endif
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;
}
/*
* 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.
*/
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 ip_vs_iphdr iph;
struct ip_vs_protocol *pp;
struct ip_vs_conn *cp;
int af;
EnterFunction(11);
af = (skb->protocol == htons(ETH_P_IP)) ? AF_INET : AF_INET6;
if (skb->ipvs_property)
return NF_ACCEPT;
ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
#ifdef CONFIG_IP_VS_IPV6
if (af == AF_INET6) {
if (unlikely(iph.protocol == IPPROTO_ICMPV6)) {
int related, verdict = ip_vs_out_icmp_v6(skb, &related);
if (related)
return verdict;
ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
}
} else
#endif
if (unlikely(iph.protocol == IPPROTO_ICMP)) {
int related, verdict = ip_vs_out_icmp(skb, &related);
if (related)
return verdict;
ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
}
pp = ip_vs_proto_get(iph.protocol);
if (unlikely(!pp))
return NF_ACCEPT;
/* reassemble IP fragments */
#ifdef CONFIG_IP_VS_IPV6
if (af == AF_INET6) {
if (unlikely(iph.protocol == IPPROTO_ICMPV6)) {
int related, verdict = ip_vs_out_icmp_v6(skb, &related);
if (related)
return verdict;
ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
}
} else
#endif
if (unlikely(ip_hdr(skb)->frag_off & htons(IP_MF|IP_OFFSET) &&
!pp->dont_defrag)) {
if (ip_vs_gather_frags(skb, IP_DEFRAG_VS_OUT))
return NF_STOLEN;
ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
}
/*
* Check if the packet belongs to an existing entry
*/
cp = pp->conn_out_get(af, skb, pp, &iph, iph.len, 0);
if (unlikely(!cp)) {
if (sysctl_ip_vs_nat_icmp_send &&
(pp->protocol == IPPROTO_TCP ||
pp->protocol == IPPROTO_UDP ||
pp->protocol == IPPROTO_SCTP)) {
__be16 _ports[2], *pptr;
pptr = skb_header_pointer(skb, iph.len,
sizeof(_ports), _ports);
if (pptr == NULL)
return NF_ACCEPT; /* Not for me */
if (ip_vs_lookup_real_service(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)
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, pp, skb, 0,
"packet continues traversal as normal");
return NF_ACCEPT;
}
return handle_response(af, skb, pp, cp, iph.len);
}
/*
* 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_iphdr ciph;
struct ip_vs_conn *cp;
struct ip_vs_protocol *pp;
unsigned int offset, ihl, verdict;
union nf_inet_addr snet;
*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) %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, pp, skb, offset, "Checking incoming ICMP for");
offset += cih->ihl * 4;
ip_vs_fill_iphdr(AF_INET, cih, &ciph);
/* The embedded headers contain source and dest in reverse order */
cp = pp->conn_in_get(AF_INET, skb, pp, &ciph, offset, 1);
if (!cp) {
/* The packet could also belong to a local client */
cp = pp->conn_out_get(AF_INET, skb, pp, &ciph, offset, 1);
if (cp) {
snet.ip = iph->saddr;
return handle_response_icmp(AF_INET, skb, &snet,
cih->protocol, cp, pp,
offset, ihl);
}
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 %pI4!\n",
&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;
}
#ifdef CONFIG_IP_VS_IPV6
static int
ip_vs_in_icmp_v6(struct sk_buff *skb, int *related, unsigned int hooknum)
{
struct ipv6hdr *iph;
struct icmp6hdr _icmph, *ic;
struct ipv6hdr _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, verdict;
union nf_inet_addr snet;
*related = 1;
/* reassemble IP fragments */
if (ipv6_hdr(skb)->nexthdr == IPPROTO_FRAGMENT) {
if (ip_vs_gather_frags_v6(skb, hooknum == NF_INET_LOCAL_IN ?
IP_DEFRAG_VS_IN :
IP_DEFRAG_VS_FWD))
return NF_STOLEN;
}
iph = ipv6_hdr(skb);
offset = sizeof(struct ipv6hdr);
ic = skb_header_pointer(skb, offset, sizeof(_icmph), &_icmph);
if (ic == NULL)
return NF_DROP;
IP_VS_DBG(12, "Incoming ICMPv6 (%d,%d) %pI6->%pI6\n",
ic->icmp6_type, ntohs(icmpv6_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->icmp6_type != ICMPV6_DEST_UNREACH) &&
(ic->icmp6_type != ICMPV6_PKT_TOOBIG) &&
(ic->icmp6_type != ICMPV6_TIME_EXCEED)) {
*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->nexthdr);
if (!pp)
return NF_ACCEPT;
/* Is the embedded protocol header present? */
/* TODO: we don't support fragmentation at the moment anyways */
if (unlikely(cih->nexthdr == IPPROTO_FRAGMENT && pp->dont_defrag))
return NF_ACCEPT;
IP_VS_DBG_PKT(11, pp, skb, offset, "Checking incoming ICMPv6 for");
offset += sizeof(struct ipv6hdr);
ip_vs_fill_iphdr(AF_INET6, cih, &ciph);
/* The embedded headers contain source and dest in reverse order */
cp = pp->conn_in_get(AF_INET6, skb, pp, &ciph, offset, 1);
if (!cp) {
/* The packet could also belong to a local client */
cp = pp->conn_out_get(AF_INET6, skb, pp, &ciph, offset, 1);
if (cp) {
ipv6_addr_copy(&snet.in6, &iph->saddr);
return handle_response_icmp(AF_INET6, skb, &snet,
cih->nexthdr,
cp, pp, offset,
sizeof(struct ipv6hdr));
}
return NF_ACCEPT;
}
verdict = NF_DROP;
/* do the statistics and put it back */
ip_vs_in_stats(cp, skb);
if (IPPROTO_TCP == cih->nexthdr || IPPROTO_UDP == cih->nexthdr ||
IPPROTO_SCTP == cih->nexthdr)
offset += 2 * sizeof(__u16);
verdict = ip_vs_icmp_xmit_v6(skb, cp, pp, offset);
/* do not touch skb anymore */
__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(unsigned int hooknum, struct sk_buff *skb,
const struct net_device *in, const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
struct ip_vs_iphdr iph;
struct ip_vs_protocol *pp;
struct ip_vs_conn *cp;
int ret, restart, af, pkts;
af = (skb->protocol == htons(ETH_P_IP)) ? AF_INET : AF_INET6;
ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
/*
* Big tappo: only PACKET_HOST, including loopback for local client
* Don't handle local packets on IPv6 for now
*/
if (unlikely(skb->pkt_type != PACKET_HOST)) {
IP_VS_DBG_BUF(12, "packet type=%d proto=%d daddr=%s ignored\n",
skb->pkt_type,
iph.protocol,
IP_VS_DBG_ADDR(af, &iph.daddr));
return NF_ACCEPT;
}
#ifdef CONFIG_IP_VS_IPV6
if (af == AF_INET6) {
if (unlikely(iph.protocol == IPPROTO_ICMPV6)) {
int related, verdict = ip_vs_in_icmp_v6(skb, &related, hooknum);
if (related)
return verdict;
ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
}
} else
#endif
if (unlikely(iph.protocol == IPPROTO_ICMP)) {
int related, verdict = ip_vs_in_icmp(skb, &related, hooknum);
if (related)
return verdict;
ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);
}
/* Protocol supported? */
pp = ip_vs_proto_get(iph.protocol);
if (unlikely(!pp))
return NF_ACCEPT;
/*
* Check if the packet belongs to an existing connection entry
*/
cp = pp->conn_in_get(af, skb, pp, &iph, iph.len, 0);
if (unlikely(!cp)) {
int v;
/* For local client packets, it could be a response */
cp = pp->conn_out_get(af, skb, pp, &iph, iph.len, 0);
if (cp)
return handle_response(af, skb, pp, cp, iph.len);
if (!pp->conn_schedule(af, 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
*/
pkts = atomic_add_return(1, &cp->in_pkts);
if (af == AF_INET && (ip_vs_sync_state & IP_VS_STATE_MASTER) &&
cp->protocol == IPPROTO_SCTP) {
if ((cp->state == IP_VS_SCTP_S_ESTABLISHED &&
(atomic_read(&cp->in_pkts) %
sysctl_ip_vs_sync_threshold[1]
== sysctl_ip_vs_sync_threshold[0])) ||
(cp->old_state != cp->state &&
((cp->state == IP_VS_SCTP_S_CLOSED) ||
(cp->state == IP_VS_SCTP_S_SHUT_ACK_CLI) ||
(cp->state == IP_VS_SCTP_S_SHUT_ACK_SER)))) {
ip_vs_sync_conn(cp);
goto out;
}
}
if (af == AF_INET &&
(ip_vs_sync_state & IP_VS_STATE_MASTER) &&
(((cp->protocol != IPPROTO_TCP ||
cp->state == IP_VS_TCP_S_ESTABLISHED) &&
(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) ||
(cp->state == IP_VS_TCP_S_CLOSE_WAIT) ||
(cp->state == IP_VS_TCP_S_TIME_WAIT)))))
ip_vs_sync_conn(cp);
out:
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);
}
#ifdef CONFIG_IP_VS_IPV6
static unsigned int
ip_vs_forward_icmp_v6(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 (ipv6_hdr(skb)->nexthdr != IPPROTO_ICMPV6)
return NF_ACCEPT;
return ip_vs_in_icmp_v6(skb, &r, hooknum);
}
#endif
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,
},
#ifdef CONFIG_IP_VS_IPV6
/* 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_INET6,
.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_INET6,
.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_v6,
.owner = THIS_MODULE,
.pf = PF_INET6,
.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_INET6,
.hooknum = NF_INET_POST_ROUTING,
.priority = NF_IP6_PRI_NAT_SRC-1,
},
#endif
};
/*
* Initialize IP Virtual Server
*/
static int __init ip_vs_init(void)
{
int ret;
ip_vs_estimator_init();
ret = ip_vs_control_init();
if (ret < 0) {
pr_err("can't setup control.\n");
goto cleanup_estimator;
}
ip_vs_protocol_init();
ret = ip_vs_app_init();
if (ret < 0) {
pr_err("can't setup application helper.\n");
goto cleanup_protocol;
}
ret = ip_vs_conn_init();
if (ret < 0) {
pr_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) {
pr_err("can't register hooks.\n");
goto cleanup_conn;
}
pr_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_estimator:
ip_vs_estimator_cleanup();
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_estimator_cleanup();
pr_info("ipvs unloaded.\n");
}
module_init(ip_vs_init);
module_exit(ip_vs_cleanup);
MODULE_LICENSE("GPL");