aboutsummaryrefslogtreecommitdiffstats
path: root/net/ipv4/ipvs/ip_vs_proto_esp.c
blob: 478e5c7c7e8e1801fb010ebf7055c10c709434c0 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
/*
 * 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/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,
				       __constant_htons(PORT_ISAKMP),
				       iph->daddr,
				       __constant_htons(PORT_ISAKMP));
	} else {
		cp = ip_vs_conn_in_get(IPPROTO_UDP,
				       iph->daddr,
				       __constant_htons(PORT_ISAKMP),
				       iph->saddr,
				       __constant_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,
					__constant_htons(PORT_ISAKMP),
					iph->daddr,
					__constant_htons(PORT_ISAKMP));
	} else {
		cp = ip_vs_conn_out_get(IPPROTO_UDP,
					iph->daddr,
					__constant_htons(PORT_ISAKMP),
					iph->saddr,
					__constant_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,
	.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 */
};