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 <linux/export.h>
19 #include <net/dsfield.h>
20 #include <net/ipv6.h>
21 #include <net/addrconf.h>
22
23 static void
__xfrm6_init_tempsel(struct xfrm_selector * sel,const struct flowi * fl)24 __xfrm6_init_tempsel(struct xfrm_selector *sel, const struct flowi *fl)
25 {
26 const struct flowi6 *fl6 = &fl->u.ip6;
27
28 /* Initialize temporary selector matching only
29 * to current session. */
30 *(struct in6_addr *)&sel->daddr = fl6->daddr;
31 *(struct in6_addr *)&sel->saddr = fl6->saddr;
32 sel->dport = xfrm_flowi_dport(fl, &fl6->uli);
33 sel->dport_mask = htons(0xffff);
34 sel->sport = xfrm_flowi_sport(fl, &fl6->uli);
35 sel->sport_mask = htons(0xffff);
36 sel->family = AF_INET6;
37 sel->prefixlen_d = 128;
38 sel->prefixlen_s = 128;
39 sel->proto = fl6->flowi6_proto;
40 sel->ifindex = fl6->flowi6_oif;
41 }
42
43 static void
xfrm6_init_temprop(struct xfrm_state * x,const struct xfrm_tmpl * tmpl,const xfrm_address_t * daddr,const xfrm_address_t * saddr)44 xfrm6_init_temprop(struct xfrm_state *x, const struct xfrm_tmpl *tmpl,
45 const xfrm_address_t *daddr, const xfrm_address_t *saddr)
46 {
47 x->id = tmpl->id;
48 if (ipv6_addr_any((struct in6_addr *)&x->id.daddr))
49 memcpy(&x->id.daddr, daddr, sizeof(x->sel.daddr));
50 memcpy(&x->props.saddr, &tmpl->saddr, sizeof(x->props.saddr));
51 if (ipv6_addr_any((struct in6_addr *)&x->props.saddr))
52 memcpy(&x->props.saddr, saddr, sizeof(x->props.saddr));
53 x->props.mode = tmpl->mode;
54 x->props.reqid = tmpl->reqid;
55 x->props.family = AF_INET6;
56 }
57
58 /* distribution counting sort function for xfrm_state and xfrm_tmpl */
59 static int
__xfrm6_sort(void ** dst,void ** src,int n,int (* cmp)(void * p),int maxclass)60 __xfrm6_sort(void **dst, void **src, int n, int (*cmp)(void *p), int maxclass)
61 {
62 int i;
63 int class[XFRM_MAX_DEPTH];
64 int count[maxclass];
65
66 memset(count, 0, sizeof(count));
67
68 for (i = 0; i < n; i++) {
69 int c;
70 class[i] = c = cmp(src[i]);
71 count[c]++;
72 }
73
74 for (i = 2; i < maxclass; i++)
75 count[i] += count[i - 1];
76
77 for (i = 0; i < n; i++) {
78 dst[count[class[i] - 1]++] = src[i];
79 src[i] = NULL;
80 }
81
82 return 0;
83 }
84
85 /*
86 * Rule for xfrm_state:
87 *
88 * rule 1: select IPsec transport except AH
89 * rule 2: select MIPv6 RO or inbound trigger
90 * rule 3: select IPsec transport AH
91 * rule 4: select IPsec tunnel
92 * rule 5: others
93 */
__xfrm6_state_sort_cmp(void * p)94 static int __xfrm6_state_sort_cmp(void *p)
95 {
96 struct xfrm_state *v = p;
97
98 switch (v->props.mode) {
99 case XFRM_MODE_TRANSPORT:
100 if (v->id.proto != IPPROTO_AH)
101 return 1;
102 else
103 return 3;
104 #if IS_ENABLED(CONFIG_IPV6_MIP6)
105 case XFRM_MODE_ROUTEOPTIMIZATION:
106 case XFRM_MODE_IN_TRIGGER:
107 return 2;
108 #endif
109 case XFRM_MODE_TUNNEL:
110 case XFRM_MODE_BEET:
111 return 4;
112 }
113 return 5;
114 }
115
116 static int
__xfrm6_state_sort(struct xfrm_state ** dst,struct xfrm_state ** src,int n)117 __xfrm6_state_sort(struct xfrm_state **dst, struct xfrm_state **src, int n)
118 {
119 return __xfrm6_sort((void **)dst, (void **)src, n,
120 __xfrm6_state_sort_cmp, 6);
121 }
122
123 /*
124 * Rule for xfrm_tmpl:
125 *
126 * rule 1: select IPsec transport
127 * rule 2: select MIPv6 RO or inbound trigger
128 * rule 3: select IPsec tunnel
129 * rule 4: others
130 */
__xfrm6_tmpl_sort_cmp(void * p)131 static int __xfrm6_tmpl_sort_cmp(void *p)
132 {
133 struct xfrm_tmpl *v = p;
134 switch (v->mode) {
135 case XFRM_MODE_TRANSPORT:
136 return 1;
137 #if IS_ENABLED(CONFIG_IPV6_MIP6)
138 case XFRM_MODE_ROUTEOPTIMIZATION:
139 case XFRM_MODE_IN_TRIGGER:
140 return 2;
141 #endif
142 case XFRM_MODE_TUNNEL:
143 case XFRM_MODE_BEET:
144 return 3;
145 }
146 return 4;
147 }
148
149 static int
__xfrm6_tmpl_sort(struct xfrm_tmpl ** dst,struct xfrm_tmpl ** src,int n)150 __xfrm6_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src, int n)
151 {
152 return __xfrm6_sort((void **)dst, (void **)src, n,
153 __xfrm6_tmpl_sort_cmp, 5);
154 }
155
xfrm6_extract_header(struct sk_buff * skb)156 int xfrm6_extract_header(struct sk_buff *skb)
157 {
158 struct ipv6hdr *iph = ipv6_hdr(skb);
159
160 XFRM_MODE_SKB_CB(skb)->ihl = sizeof(*iph);
161 XFRM_MODE_SKB_CB(skb)->id = 0;
162 XFRM_MODE_SKB_CB(skb)->frag_off = htons(IP_DF);
163 XFRM_MODE_SKB_CB(skb)->tos = ipv6_get_dsfield(iph);
164 XFRM_MODE_SKB_CB(skb)->ttl = iph->hop_limit;
165 XFRM_MODE_SKB_CB(skb)->optlen = 0;
166 memcpy(XFRM_MODE_SKB_CB(skb)->flow_lbl, iph->flow_lbl,
167 sizeof(XFRM_MODE_SKB_CB(skb)->flow_lbl));
168
169 return 0;
170 }
171
172 static struct xfrm_state_afinfo xfrm6_state_afinfo = {
173 .family = AF_INET6,
174 .proto = IPPROTO_IPV6,
175 .eth_proto = htons(ETH_P_IPV6),
176 .owner = THIS_MODULE,
177 .init_tempsel = __xfrm6_init_tempsel,
178 .init_temprop = xfrm6_init_temprop,
179 .tmpl_sort = __xfrm6_tmpl_sort,
180 .state_sort = __xfrm6_state_sort,
181 .output = xfrm6_output,
182 .output_finish = xfrm6_output_finish,
183 .extract_input = xfrm6_extract_input,
184 .extract_output = xfrm6_extract_output,
185 .transport_finish = xfrm6_transport_finish,
186 .local_error = xfrm6_local_error,
187 };
188
xfrm6_state_init(void)189 int __init xfrm6_state_init(void)
190 {
191 return xfrm_state_register_afinfo(&xfrm6_state_afinfo);
192 }
193
xfrm6_state_fini(void)194 void xfrm6_state_fini(void)
195 {
196 xfrm_state_unregister_afinfo(&xfrm6_state_afinfo);
197 }
198
199