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/*
* ip_vs_proto_esp.c: ESP IPSec load balancing support for IPVS
*
* Version: $Id: ip_vs_proto_esp.c,v 1.1 2003/07/04 15:04:37 wensong Exp $
*
* Authors: Julian Anastasov <ja@ssi.bg>, February 2002
* Wensong Zhang <wensong@linuxvirtualserver.org>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation;
*
*/
#include <linux/in.h>
#include <linux/ip.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv4.h>
#include <net/ip_vs.h>
/* TODO:
struct isakmp_hdr {
__u8 icookie[8];
__u8 rcookie[8];
__u8 np;
__u8 version;
__u8 xchgtype;
__u8 flags;
__u32 msgid;
__u32 length;
};
*/
#define PORT_ISAKMP 500
static struct ip_vs_conn *
esp_conn_in_get(const struct sk_buff *skb,
struct ip_vs_protocol *pp,
const struct iphdr *iph,
unsigned int proto_off,
int inverse)
{
struct ip_vs_conn *cp;
if (likely(!inverse)) {
cp = ip_vs_conn_in_get(IPPROTO_UDP,
iph->saddr,
htons(PORT_ISAKMP),
iph->daddr,
htons(PORT_ISAKMP));
} else {
cp = ip_vs_conn_in_get(IPPROTO_UDP,
iph->daddr,
htons(PORT_ISAKMP),
iph->saddr,
htons(PORT_ISAKMP));
}
if (!cp) {
/*
* We are not sure if the packet is from our
* service, so our conn_schedule hook should return NF_ACCEPT
*/
IP_VS_DBG(12, "Unknown ISAKMP entry for outin packet "
"%s%s %u.%u.%u.%u->%u.%u.%u.%u\n",
inverse ? "ICMP+" : "",
pp->name,
NIPQUAD(iph->saddr),
NIPQUAD(iph->daddr));
}
return cp;
}
static struct ip_vs_conn *
esp_conn_out_get(const struct sk_buff *skb, struct ip_vs_protocol *pp,
const struct iphdr *iph, unsigned int proto_off, int inverse)
{
struct ip_vs_conn *cp;
if (likely(!inverse)) {
cp = ip_vs_conn_out_get(IPPROTO_UDP,
iph->saddr,
htons(PORT_ISAKMP),
iph->daddr,
htons(PORT_ISAKMP));
} else {
cp = ip_vs_conn_out_get(IPPROTO_UDP,
iph->daddr,
htons(PORT_ISAKMP),
iph->saddr,
htons(PORT_ISAKMP));
}
if (!cp) {
IP_VS_DBG(12, "Unknown ISAKMP entry for inout packet "
"%s%s %u.%u.%u.%u->%u.%u.%u.%u\n",
inverse ? "ICMP+" : "",
pp->name,
NIPQUAD(iph->saddr),
NIPQUAD(iph->daddr));
}
return cp;
}
static int
esp_conn_schedule(struct sk_buff *skb, struct ip_vs_protocol *pp,
int *verdict, struct ip_vs_conn **cpp)
{
/*
* ESP is only related traffic. Pass the packet to IP stack.
*/
*verdict = NF_ACCEPT;
return 0;
}
static void
esp_debug_packet(struct ip_vs_protocol *pp, const struct sk_buff *skb,
int offset, const char *msg)
{
char buf[256];
struct iphdr _iph, *ih;
ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
if (ih == NULL)
sprintf(buf, "%s TRUNCATED", pp->name);
else
sprintf(buf, "%s %u.%u.%u.%u->%u.%u.%u.%u",
pp->name, NIPQUAD(ih->saddr),
NIPQUAD(ih->daddr));
printk(KERN_DEBUG "IPVS: %s: %s\n", msg, buf);
}
static void esp_init(struct ip_vs_protocol *pp)
{
/* nothing to do now */
}
static void esp_exit(struct ip_vs_protocol *pp)
{
/* nothing to do now */
}
struct ip_vs_protocol ip_vs_protocol_esp = {
.name = "ESP",
.protocol = IPPROTO_ESP,
.num_states = 1,
.dont_defrag = 1,
.init = esp_init,
.exit = esp_exit,
.conn_schedule = esp_conn_schedule,
.conn_in_get = esp_conn_in_get,
.conn_out_get = esp_conn_out_get,
.snat_handler = NULL,
.dnat_handler = NULL,
.csum_check = NULL,
.state_transition = NULL,
.register_app = NULL,
.unregister_app = NULL,
.app_conn_bind = NULL,
.debug_packet = esp_debug_packet,
.timeout_change = NULL, /* ISAKMP */
};
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