ipvs: fix oops in backup for fwmark conn templates
[linux-2.6.git] / net / ipv4 / ipvs / ip_vs_proto_esp.c
1 /*
2  * ip_vs_proto_esp.c:   ESP IPSec load balancing support for IPVS
3  *
4  * Version:     $Id: ip_vs_proto_esp.c,v 1.1 2003/07/04 15:04:37 wensong Exp $
5  *
6  * Authors:     Julian Anastasov <ja@ssi.bg>, February 2002
7  *              Wensong Zhang <wensong@linuxvirtualserver.org>
8  *
9  *              This program is free software; you can redistribute it and/or
10  *              modify it under the terms of the GNU General Public License
11  *              version 2 as published by the Free Software Foundation;
12  *
13  */
14
15 #include <linux/in.h>
16 #include <linux/ip.h>
17 #include <linux/module.h>
18 #include <linux/kernel.h>
19 #include <linux/netfilter.h>
20 #include <linux/netfilter_ipv4.h>
21
22 #include <net/ip_vs.h>
23
24
25 /* TODO:
26
27 struct isakmp_hdr {
28         __u8            icookie[8];
29         __u8            rcookie[8];
30         __u8            np;
31         __u8            version;
32         __u8            xchgtype;
33         __u8            flags;
34         __u32           msgid;
35         __u32           length;
36 };
37
38 */
39
40 #define PORT_ISAKMP     500
41
42
43 static struct ip_vs_conn *
44 esp_conn_in_get(const struct sk_buff *skb,
45                 struct ip_vs_protocol *pp,
46                 const struct iphdr *iph,
47                 unsigned int proto_off,
48                 int inverse)
49 {
50         struct ip_vs_conn *cp;
51
52         if (likely(!inverse)) {
53                 cp = ip_vs_conn_in_get(IPPROTO_UDP,
54                                        iph->saddr,
55                                        htons(PORT_ISAKMP),
56                                        iph->daddr,
57                                        htons(PORT_ISAKMP));
58         } else {
59                 cp = ip_vs_conn_in_get(IPPROTO_UDP,
60                                        iph->daddr,
61                                        htons(PORT_ISAKMP),
62                                        iph->saddr,
63                                        htons(PORT_ISAKMP));
64         }
65
66         if (!cp) {
67                 /*
68                  * We are not sure if the packet is from our
69                  * service, so our conn_schedule hook should return NF_ACCEPT
70                  */
71                 IP_VS_DBG(12, "Unknown ISAKMP entry for outin packet "
72                           "%s%s %u.%u.%u.%u->%u.%u.%u.%u\n",
73                           inverse ? "ICMP+" : "",
74                           pp->name,
75                           NIPQUAD(iph->saddr),
76                           NIPQUAD(iph->daddr));
77         }
78
79         return cp;
80 }
81
82
83 static struct ip_vs_conn *
84 esp_conn_out_get(const struct sk_buff *skb, struct ip_vs_protocol *pp,
85                  const struct iphdr *iph, unsigned int proto_off, int inverse)
86 {
87         struct ip_vs_conn *cp;
88
89         if (likely(!inverse)) {
90                 cp = ip_vs_conn_out_get(IPPROTO_UDP,
91                                         iph->saddr,
92                                         htons(PORT_ISAKMP),
93                                         iph->daddr,
94                                         htons(PORT_ISAKMP));
95         } else {
96                 cp = ip_vs_conn_out_get(IPPROTO_UDP,
97                                         iph->daddr,
98                                         htons(PORT_ISAKMP),
99                                         iph->saddr,
100                                         htons(PORT_ISAKMP));
101         }
102
103         if (!cp) {
104                 IP_VS_DBG(12, "Unknown ISAKMP entry for inout packet "
105                           "%s%s %u.%u.%u.%u->%u.%u.%u.%u\n",
106                           inverse ? "ICMP+" : "",
107                           pp->name,
108                           NIPQUAD(iph->saddr),
109                           NIPQUAD(iph->daddr));
110         }
111
112         return cp;
113 }
114
115
116 static int
117 esp_conn_schedule(struct sk_buff *skb, struct ip_vs_protocol *pp,
118                   int *verdict, struct ip_vs_conn **cpp)
119 {
120         /*
121          * ESP is only related traffic. Pass the packet to IP stack.
122          */
123         *verdict = NF_ACCEPT;
124         return 0;
125 }
126
127
128 static void
129 esp_debug_packet(struct ip_vs_protocol *pp, const struct sk_buff *skb,
130                  int offset, const char *msg)
131 {
132         char buf[256];
133         struct iphdr _iph, *ih;
134
135         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
136         if (ih == NULL)
137                 sprintf(buf, "%s TRUNCATED", pp->name);
138         else
139                 sprintf(buf, "%s %u.%u.%u.%u->%u.%u.%u.%u",
140                         pp->name, NIPQUAD(ih->saddr),
141                         NIPQUAD(ih->daddr));
142
143         printk(KERN_DEBUG "IPVS: %s: %s\n", msg, buf);
144 }
145
146
147 static void esp_init(struct ip_vs_protocol *pp)
148 {
149         /* nothing to do now */
150 }
151
152
153 static void esp_exit(struct ip_vs_protocol *pp)
154 {
155         /* nothing to do now */
156 }
157
158
159 struct ip_vs_protocol ip_vs_protocol_esp = {
160         .name =                 "ESP",
161         .protocol =             IPPROTO_ESP,
162         .num_states =           1,
163         .dont_defrag =          1,
164         .init =                 esp_init,
165         .exit =                 esp_exit,
166         .conn_schedule =        esp_conn_schedule,
167         .conn_in_get =          esp_conn_in_get,
168         .conn_out_get =         esp_conn_out_get,
169         .snat_handler =         NULL,
170         .dnat_handler =         NULL,
171         .csum_check =           NULL,
172         .state_transition =     NULL,
173         .register_app =         NULL,
174         .unregister_app =       NULL,
175         .app_conn_bind =        NULL,
176         .debug_packet =         esp_debug_packet,
177         .timeout_change =       NULL,           /* ISAKMP */
178 };