[XFRM]: xfrm_state_lookup() annotations
[linux-2.6] / 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 <net/ipv6.h>
18 #include <net/addrconf.h>
19
20 static struct xfrm_state_afinfo xfrm6_state_afinfo;
21
22 static void
23 __xfrm6_init_tempsel(struct xfrm_state *x, struct flowi *fl,
24                      struct xfrm_tmpl *tmpl,
25                      xfrm_address_t *daddr, xfrm_address_t *saddr)
26 {
27         /* Initialize temporary selector matching only
28          * to current session. */
29         ipv6_addr_copy((struct in6_addr *)&x->sel.daddr, &fl->fl6_dst);
30         ipv6_addr_copy((struct in6_addr *)&x->sel.saddr, &fl->fl6_src);
31         x->sel.dport = xfrm_flowi_dport(fl);
32         x->sel.dport_mask = htons(0xffff);
33         x->sel.sport = xfrm_flowi_sport(fl);
34         x->sel.sport_mask = htons(0xffff);
35         x->sel.prefixlen_d = 128;
36         x->sel.prefixlen_s = 128;
37         x->sel.proto = fl->proto;
38         x->sel.ifindex = fl->oif;
39         x->id = tmpl->id;
40         if (ipv6_addr_any((struct in6_addr*)&x->id.daddr))
41                 memcpy(&x->id.daddr, daddr, sizeof(x->sel.daddr));
42         memcpy(&x->props.saddr, &tmpl->saddr, sizeof(x->props.saddr));
43         if (ipv6_addr_any((struct in6_addr*)&x->props.saddr))
44                 memcpy(&x->props.saddr, saddr, sizeof(x->props.saddr));
45         x->props.mode = tmpl->mode;
46         x->props.reqid = tmpl->reqid;
47         x->props.family = AF_INET6;
48 }
49
50 static int
51 __xfrm6_state_sort(struct xfrm_state **dst, struct xfrm_state **src, int n)
52 {
53         int i;
54         int j = 0;
55
56         /* Rule 1: select IPsec transport except AH */
57         for (i = 0; i < n; i++) {
58                 if (src[i]->props.mode == XFRM_MODE_TRANSPORT &&
59                     src[i]->id.proto != IPPROTO_AH) {
60                         dst[j++] = src[i];
61                         src[i] = NULL;
62                 }
63         }
64         if (j == n)
65                 goto end;
66
67         /* Rule 2: select MIPv6 RO or inbound trigger */
68 #ifdef CONFIG_IPV6_MIP6
69         for (i = 0; i < n; i++) {
70                 if (src[i] &&
71                     (src[i]->props.mode == XFRM_MODE_ROUTEOPTIMIZATION ||
72                      src[i]->props.mode == XFRM_MODE_IN_TRIGGER)) {
73                         dst[j++] = src[i];
74                         src[i] = NULL;
75                 }
76         }
77         if (j == n)
78                 goto end;
79 #endif
80
81         /* Rule 3: select IPsec transport AH */
82         for (i = 0; i < n; i++) {
83                 if (src[i] &&
84                     src[i]->props.mode == XFRM_MODE_TRANSPORT &&
85                     src[i]->id.proto == IPPROTO_AH) {
86                         dst[j++] = src[i];
87                         src[i] = NULL;
88                 }
89         }
90         if (j == n)
91                 goto end;
92
93         /* Rule 4: select IPsec tunnel */
94         for (i = 0; i < n; i++) {
95                 if (src[i] &&
96                     src[i]->props.mode == XFRM_MODE_TUNNEL) {
97                         dst[j++] = src[i];
98                         src[i] = NULL;
99                 }
100         }
101         if (likely(j == n))
102                 goto end;
103
104         /* Final rule */
105         for (i = 0; i < n; i++) {
106                 if (src[i]) {
107                         dst[j++] = src[i];
108                         src[i] = NULL;
109                 }
110         }
111
112  end:
113         return 0;
114 }
115
116 static int
117 __xfrm6_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src, int n)
118 {
119         int i;
120         int j = 0;
121
122         /* Rule 1: select IPsec transport */
123         for (i = 0; i < n; i++) {
124                 if (src[i]->mode == XFRM_MODE_TRANSPORT) {
125                         dst[j++] = src[i];
126                         src[i] = NULL;
127                 }
128         }
129         if (j == n)
130                 goto end;
131
132         /* Rule 2: select MIPv6 RO or inbound trigger */
133 #ifdef CONFIG_IPV6_MIP6
134         for (i = 0; i < n; i++) {
135                 if (src[i] &&
136                     (src[i]->mode == XFRM_MODE_ROUTEOPTIMIZATION ||
137                      src[i]->mode == XFRM_MODE_IN_TRIGGER)) {
138                         dst[j++] = src[i];
139                         src[i] = NULL;
140                 }
141         }
142         if (j == n)
143                 goto end;
144 #endif
145
146         /* Rule 3: select IPsec tunnel */
147         for (i = 0; i < n; i++) {
148                 if (src[i] &&
149                     src[i]->mode == XFRM_MODE_TUNNEL) {
150                         dst[j++] = src[i];
151                         src[i] = NULL;
152                 }
153         }
154         if (likely(j == n))
155                 goto end;
156
157         /* Final rule */
158         for (i = 0; i < n; i++) {
159                 if (src[i]) {
160                         dst[j++] = src[i];
161                         src[i] = NULL;
162                 }
163         }
164
165  end:
166         return 0;
167 }
168
169 static struct xfrm_state_afinfo xfrm6_state_afinfo = {
170         .family                 = AF_INET6,
171         .init_tempsel           = __xfrm6_init_tempsel,
172         .tmpl_sort              = __xfrm6_tmpl_sort,
173         .state_sort             = __xfrm6_state_sort,
174 };
175
176 void __init xfrm6_state_init(void)
177 {
178         xfrm_state_register_afinfo(&xfrm6_state_afinfo);
179 }
180
181 void xfrm6_state_fini(void)
182 {
183         xfrm_state_unregister_afinfo(&xfrm6_state_afinfo);
184 }
185