sit: fix regression: do not release skb->dst before xmit
[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 <linux/netfilter_ipv6.h>
18 #include <net/dsfield.h>
19 #include <net/ipv6.h>
20 #include <net/addrconf.h>
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.family = AF_INET6;
36         x->sel.prefixlen_d = 128;
37         x->sel.prefixlen_s = 128;
38         x->sel.proto = fl->proto;
39         x->sel.ifindex = fl->oif;
40         x->id = tmpl->id;
41         if (ipv6_addr_any((struct in6_addr*)&x->id.daddr))
42                 memcpy(&x->id.daddr, daddr, sizeof(x->sel.daddr));
43         memcpy(&x->props.saddr, &tmpl->saddr, sizeof(x->props.saddr));
44         if (ipv6_addr_any((struct in6_addr*)&x->props.saddr))
45                 memcpy(&x->props.saddr, saddr, sizeof(x->props.saddr));
46         x->props.mode = tmpl->mode;
47         x->props.reqid = tmpl->reqid;
48         x->props.family = AF_INET6;
49 }
50
51 /* distribution counting sort function for xfrm_state and xfrm_tmpl */
52 static int
53 __xfrm6_sort(void **dst, void **src, int n, int (*cmp)(void *p), int maxclass)
54 {
55         int i;
56         int class[XFRM_MAX_DEPTH];
57         int count[maxclass];
58
59         memset(count, 0, sizeof(count));
60
61         for (i = 0; i < n; i++) {
62                 int c;
63                 class[i] = c = cmp(src[i]);
64                 count[c]++;
65         }
66
67         for (i = 2; i < maxclass; i++)
68                 count[i] += count[i - 1];
69
70         for (i = 0; i < n; i++) {
71                 dst[count[class[i] - 1]++] = src[i];
72                 src[i] = NULL;
73         }
74
75         return 0;
76 }
77
78 /*
79  * Rule for xfrm_state:
80  *
81  * rule 1: select IPsec transport except AH
82  * rule 2: select MIPv6 RO or inbound trigger
83  * rule 3: select IPsec transport AH
84  * rule 4: select IPsec tunnel
85  * rule 5: others
86  */
87 static int __xfrm6_state_sort_cmp(void *p)
88 {
89         struct xfrm_state *v = p;
90
91         switch (v->props.mode) {
92         case XFRM_MODE_TRANSPORT:
93                 if (v->id.proto != IPPROTO_AH)
94                         return 1;
95                 else
96                         return 3;
97 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
98         case XFRM_MODE_ROUTEOPTIMIZATION:
99         case XFRM_MODE_IN_TRIGGER:
100                 return 2;
101 #endif
102         case XFRM_MODE_TUNNEL:
103         case XFRM_MODE_BEET:
104                 return 4;
105         }
106         return 5;
107 }
108
109 static int
110 __xfrm6_state_sort(struct xfrm_state **dst, struct xfrm_state **src, int n)
111 {
112         return __xfrm6_sort((void **)dst, (void **)src, n,
113                             __xfrm6_state_sort_cmp, 6);
114 }
115
116 /*
117  * Rule for xfrm_tmpl:
118  *
119  * rule 1: select IPsec transport
120  * rule 2: select MIPv6 RO or inbound trigger
121  * rule 3: select IPsec tunnel
122  * rule 4: others
123  */
124 static int __xfrm6_tmpl_sort_cmp(void *p)
125 {
126         struct xfrm_tmpl *v = p;
127         switch (v->mode) {
128         case XFRM_MODE_TRANSPORT:
129                 return 1;
130 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
131         case XFRM_MODE_ROUTEOPTIMIZATION:
132         case XFRM_MODE_IN_TRIGGER:
133                 return 2;
134 #endif
135         case XFRM_MODE_TUNNEL:
136         case XFRM_MODE_BEET:
137                 return 3;
138         }
139         return 4;
140 }
141
142 static int
143 __xfrm6_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src, int n)
144 {
145         return __xfrm6_sort((void **)dst, (void **)src, n,
146                             __xfrm6_tmpl_sort_cmp, 5);
147 }
148
149 int xfrm6_extract_header(struct sk_buff *skb)
150 {
151         struct ipv6hdr *iph = ipv6_hdr(skb);
152
153         XFRM_MODE_SKB_CB(skb)->ihl = sizeof(*iph);
154         XFRM_MODE_SKB_CB(skb)->id = 0;
155         XFRM_MODE_SKB_CB(skb)->frag_off = htons(IP_DF);
156         XFRM_MODE_SKB_CB(skb)->tos = ipv6_get_dsfield(iph);
157         XFRM_MODE_SKB_CB(skb)->ttl = iph->hop_limit;
158         XFRM_MODE_SKB_CB(skb)->optlen = 0;
159         memcpy(XFRM_MODE_SKB_CB(skb)->flow_lbl, iph->flow_lbl,
160                sizeof(XFRM_MODE_SKB_CB(skb)->flow_lbl));
161
162         return 0;
163 }
164
165 static struct xfrm_state_afinfo xfrm6_state_afinfo = {
166         .family                 = AF_INET6,
167         .proto                  = IPPROTO_IPV6,
168         .eth_proto              = htons(ETH_P_IPV6),
169         .owner                  = THIS_MODULE,
170         .init_tempsel           = __xfrm6_init_tempsel,
171         .tmpl_sort              = __xfrm6_tmpl_sort,
172         .state_sort             = __xfrm6_state_sort,
173         .output                 = xfrm6_output,
174         .extract_input          = xfrm6_extract_input,
175         .extract_output         = xfrm6_extract_output,
176         .transport_finish       = xfrm6_transport_finish,
177 };
178
179 int __init xfrm6_state_init(void)
180 {
181         return xfrm_state_register_afinfo(&xfrm6_state_afinfo);
182 }
183
184 void xfrm6_state_fini(void)
185 {
186         xfrm_state_unregister_afinfo(&xfrm6_state_afinfo);
187 }
188