89884a4f23aa27992e006846bf14dd5673fea675
[linux-2.6.git] / net / ipv6 / xfrm6_state.c
1 /*
2  * xfrm6_state.c: based on xfrm4_state.c
3  *
4  * Authors:
5  *      Mitsuru KANDA @USAGI
6  *      Kazunori MIYAZAWA @USAGI
7  *      Kunihiro Ishiguro <kunihiro@ipinfusion.com>
8  *              IPv6 support
9  *      YOSHIFUJI Hideaki @USAGI
10  *              Split up af-specific portion
11  *
12  */
13
14 #include <net/xfrm.h>
15 #include <linux/pfkeyv2.h>
16 #include <linux/ipsec.h>
17 #include <linux/netfilter_ipv6.h>
18 #include <net/dsfield.h>
19 #include <net/ipv6.h>
20 #include <net/addrconf.h>
21
22 static struct xfrm_state_afinfo xfrm6_state_afinfo;
23
24 static void
25 __xfrm6_init_tempsel(struct xfrm_state *x, struct flowi *fl,
26                      struct xfrm_tmpl *tmpl,
27                      xfrm_address_t *daddr, xfrm_address_t *saddr)
28 {
29         /* Initialize temporary selector matching only
30          * to current session. */
31         ipv6_addr_copy((struct in6_addr *)&x->sel.daddr, &fl->fl6_dst);
32         ipv6_addr_copy((struct in6_addr *)&x->sel.saddr, &fl->fl6_src);
33         x->sel.dport = xfrm_flowi_dport(fl);
34         x->sel.dport_mask = htons(0xffff);
35         x->sel.sport = xfrm_flowi_sport(fl);
36         x->sel.sport_mask = htons(0xffff);
37         x->sel.prefixlen_d = 128;
38         x->sel.prefixlen_s = 128;
39         x->sel.proto = fl->proto;
40         x->sel.ifindex = fl->oif;
41         x->id = tmpl->id;
42         if (ipv6_addr_any((struct in6_addr*)&x->id.daddr))
43                 memcpy(&x->id.daddr, daddr, sizeof(x->sel.daddr));
44         memcpy(&x->props.saddr, &tmpl->saddr, sizeof(x->props.saddr));
45         if (ipv6_addr_any((struct in6_addr*)&x->props.saddr))
46                 memcpy(&x->props.saddr, saddr, sizeof(x->props.saddr));
47         x->props.mode = tmpl->mode;
48         x->props.reqid = tmpl->reqid;
49         x->props.family = AF_INET6;
50 }
51
52 /* distribution counting sort function for xfrm_state and xfrm_tmpl */
53 static int
54 __xfrm6_sort(void **dst, void **src, int n, int (*cmp)(void *p), int maxclass)
55 {
56         int i;
57         int class[XFRM_MAX_DEPTH];
58         int count[maxclass];
59
60         memset(count, 0, sizeof(count));
61
62         for (i = 0; i < n; i++) {
63                 int c;
64                 class[i] = c = cmp(src[i]);
65                 count[c]++;
66         }
67
68         for (i = 2; i < maxclass; i++)
69                 count[i] += count[i - 1];
70
71         for (i = 0; i < n; i++) {
72                 dst[count[class[i] - 1]++] = src[i];
73                 src[i] = 0;
74         }
75
76         return 0;
77 }
78
79 /*
80  * Rule for xfrm_state:
81  *
82  * rule 1: select IPsec transport except AH
83  * rule 2: select MIPv6 RO or inbound trigger
84  * rule 3: select IPsec transport AH
85  * rule 4: select IPsec tunnel
86  * rule 5: others
87  */
88 static int __xfrm6_state_sort_cmp(void *p)
89 {
90         struct xfrm_state *v = p;
91
92         switch (v->props.mode) {
93         case XFRM_MODE_TRANSPORT:
94                 if (v->id.proto != IPPROTO_AH)
95                         return 1;
96                 else
97                         return 3;
98 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
99         case XFRM_MODE_ROUTEOPTIMIZATION:
100         case XFRM_MODE_IN_TRIGGER:
101                 return 2;
102 #endif
103         case XFRM_MODE_TUNNEL:
104         case XFRM_MODE_BEET:
105                 return 4;
106         }
107         return 5;
108 }
109
110 static int
111 __xfrm6_state_sort(struct xfrm_state **dst, struct xfrm_state **src, int n)
112 {
113         return __xfrm6_sort((void **)dst, (void **)src, n,
114                             __xfrm6_state_sort_cmp, 6);
115 }
116
117 /*
118  * Rule for xfrm_tmpl:
119  *
120  * rule 1: select IPsec transport
121  * rule 2: select MIPv6 RO or inbound trigger
122  * rule 3: select IPsec tunnel
123  * rule 4: others
124  */
125 static int __xfrm6_tmpl_sort_cmp(void *p)
126 {
127         struct xfrm_tmpl *v = p;
128         switch (v->mode) {
129         case XFRM_MODE_TRANSPORT:
130                 return 1;
131 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
132         case XFRM_MODE_ROUTEOPTIMIZATION:
133         case XFRM_MODE_IN_TRIGGER:
134                 return 2;
135 #endif
136         case XFRM_MODE_TUNNEL:
137         case XFRM_MODE_BEET:
138                 return 3;
139         }
140         return 4;
141 }
142
143 static int
144 __xfrm6_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src, int n)
145 {
146         return __xfrm6_sort((void **)dst, (void **)src, n,
147                             __xfrm6_tmpl_sort_cmp, 5);
148 }
149
150 int xfrm6_extract_header(struct sk_buff *skb)
151 {
152         struct ipv6hdr *iph = ipv6_hdr(skb);
153
154         XFRM_MODE_SKB_CB(skb)->ihl = sizeof(*iph);
155         XFRM_MODE_SKB_CB(skb)->id = 0;
156         XFRM_MODE_SKB_CB(skb)->frag_off = htons(IP_DF);
157         XFRM_MODE_SKB_CB(skb)->tos = ipv6_get_dsfield(iph);
158         XFRM_MODE_SKB_CB(skb)->ttl = iph->hop_limit;
159         XFRM_MODE_SKB_CB(skb)->optlen = 0;
160         memcpy(XFRM_MODE_SKB_CB(skb)->flow_lbl, iph->flow_lbl,
161                sizeof(XFRM_MODE_SKB_CB(skb)->flow_lbl));
162
163         return 0;
164 }
165
166 static struct xfrm_state_afinfo xfrm6_state_afinfo = {
167         .family                 = AF_INET6,
168         .proto                  = IPPROTO_IPV6,
169         .eth_proto              = htons(ETH_P_IPV6),
170         .owner                  = THIS_MODULE,
171         .init_tempsel           = __xfrm6_init_tempsel,
172         .tmpl_sort              = __xfrm6_tmpl_sort,
173         .state_sort             = __xfrm6_state_sort,
174         .output                 = xfrm6_output,
175         .extract_input          = xfrm6_extract_input,
176         .extract_output         = xfrm6_extract_output,
177         .transport_finish       = xfrm6_transport_finish,
178 };
179
180 int __init xfrm6_state_init(void)
181 {
182         return xfrm_state_register_afinfo(&xfrm6_state_afinfo);
183 }
184
185 void xfrm6_state_fini(void)
186 {
187         xfrm_state_unregister_afinfo(&xfrm6_state_afinfo);
188 }
189