aboutsummaryrefslogtreecommitdiffstats
path: root/net/ipv6/xfrm6_state.c
blob: ff1e1db8e236009910ed6d9258eef5f961b8fb08 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
/*
 * xfrm6_state.c: based on xfrm4_state.c
 *
 * Authors:
 *	Mitsuru KANDA @USAGI
 * 	Kazunori MIYAZAWA @USAGI
 * 	Kunihiro Ishiguro <kunihiro@ipinfusion.com>
 * 		IPv6 support
 * 	YOSHIFUJI Hideaki @USAGI
 * 		Split up af-specific portion
 *
 */

#include <net/xfrm.h>
#include <linux/pfkeyv2.h>
#include <linux/ipsec.h>
#include <linux/netfilter_ipv6.h>
#include <net/dsfield.h>
#include <net/ipv6.h>
#include <net/addrconf.h>

static struct xfrm_state_afinfo xfrm6_state_afinfo;

static void
__xfrm6_init_tempsel(struct xfrm_state *x, struct flowi *fl,
		     struct xfrm_tmpl *tmpl,
		     xfrm_address_t *daddr, xfrm_address_t *saddr)
{
	/* Initialize temporary selector matching only
	 * to current session. */
	ipv6_addr_copy((struct in6_addr *)&x->sel.daddr, &fl->fl6_dst);
	ipv6_addr_copy((struct in6_addr *)&x->sel.saddr, &fl->fl6_src);
	x->sel.dport = xfrm_flowi_dport(fl);
	x->sel.dport_mask = htons(0xffff);
	x->sel.sport = xfrm_flowi_sport(fl);
	x->sel.sport_mask = htons(0xffff);
	x->sel.prefixlen_d = 128;
	x->sel.prefixlen_s = 128;
	x->sel.proto = fl->proto;
	x->sel.ifindex = fl->oif;
	x->id = tmpl->id;
	if (ipv6_addr_any((struct in6_addr*)&x->id.daddr))
		memcpy(&x->id.daddr, daddr, sizeof(x->sel.daddr));
	memcpy(&x->props.saddr, &tmpl->saddr, sizeof(x->props.saddr));
	if (ipv6_addr_any((struct in6_addr*)&x->props.saddr))
		memcpy(&x->props.saddr, saddr, sizeof(x->props.saddr));
	x->props.mode = tmpl->mode;
	x->props.reqid = tmpl->reqid;
	x->props.family = AF_INET6;
}

static int
__xfrm6_state_sort(struct xfrm_state **dst, struct xfrm_state **src, int n)
{
	int i;
	int j = 0;

	/* Rule 1: select IPsec transport except AH */
	for (i = 0; i < n; i++) {
		if (src[i]->props.mode == XFRM_MODE_TRANSPORT &&
		    src[i]->id.proto != IPPROTO_AH) {
			dst[j++] = src[i];
			src[i] = NULL;
		}
	}
	if (j == n)
		goto end;

	/* Rule 2: select MIPv6 RO or inbound trigger */
#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
	for (i = 0; i < n; i++) {
		if (src[i] &&
		    (src[i]->props.mode == XFRM_MODE_ROUTEOPTIMIZATION ||
		     src[i]->props.mode == XFRM_MODE_IN_TRIGGER)) {
			dst[j++] = src[i];
			src[i] = NULL;
		}
	}
	if (j == n)
		goto end;
#endif

	/* Rule 3: select IPsec transport AH */
	for (i = 0; i < n; i++) {
		if (src[i] &&
		    src[i]->props.mode == XFRM_MODE_TRANSPORT &&
		    src[i]->id.proto == IPPROTO_AH) {
			dst[j++] = src[i];
			src[i] = NULL;
		}
	}
	if (j == n)
		goto end;

	/* Rule 4: select IPsec tunnel */
	for (i = 0; i < n; i++) {
		if (src[i] &&
		    (src[i]->props.mode == XFRM_MODE_TUNNEL ||
		     src[i]->props.mode == XFRM_MODE_BEET)) {
			dst[j++] = src[i];
			src[i] = NULL;
		}
	}
	if (likely(j == n))
		goto end;

	/* Final rule */
	for (i = 0; i < n; i++) {
		if (src[i]) {
			dst[j++] = src[i];
			src[i] = NULL;
		}
	}

 end:
	return 0;
}

static int
__xfrm6_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src, int n)
{
	int i;
	int j = 0;

	/* Rule 1: select IPsec transport */
	for (i = 0; i < n; i++) {
		if (src[i]->mode == XFRM_MODE_TRANSPORT) {
			dst[j++] = src[i];
			src[i] = NULL;
		}
	}
	if (j == n)
		goto end;

	/* Rule 2: select MIPv6 RO or inbound trigger */
#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
	for (i = 0; i < n; i++) {
		if (src[i] &&
		    (src[i]->mode == XFRM_MODE_ROUTEOPTIMIZATION ||
		     src[i]->mode == XFRM_MODE_IN_TRIGGER)) {
			dst[j++] = src[i];
			src[i] = NULL;
		}
	}
	if (j == n)
		goto end;
#endif

	/* Rule 3: select IPsec tunnel */
	for (i = 0; i < n; i++) {
		if (src[i] &&
		    (src[i]->mode == XFRM_MODE_TUNNEL ||
		     src[i]->mode == XFRM_MODE_BEET)) {
			dst[j++] = src[i];
			src[i] = NULL;
		}
	}
	if (likely(j == n))
		goto end;

	/* Final rule */
	for (i = 0; i < n; i++) {
		if (src[i]) {
			dst[j++] = src[i];
			src[i] = NULL;
		}
	}

 end:
	return 0;
}

int xfrm6_extract_header(struct sk_buff *skb)
{
	struct ipv6hdr *iph = ipv6_hdr(skb);

	XFRM_MODE_SKB_CB(skb)->ihl = sizeof(*iph);
	XFRM_MODE_SKB_CB(skb)->id = 0;
	XFRM_MODE_SKB_CB(skb)->frag_off = htons(IP_DF);
	XFRM_MODE_SKB_CB(skb)->tos = ipv6_get_dsfield(iph);
	XFRM_MODE_SKB_CB(skb)->ttl = iph->hop_limit;
	XFRM_MODE_SKB_CB(skb)->optlen = 0;
	memcpy(XFRM_MODE_SKB_CB(skb)->flow_lbl, iph->flow_lbl,
	       sizeof(XFRM_MODE_SKB_CB(skb)->flow_lbl));

	return 0;
}

static struct xfrm_state_afinfo xfrm6_state_afinfo = {
	.family			= AF_INET6,
	.proto			= IPPROTO_IPV6,
	.eth_proto		= htons(ETH_P_IPV6),
	.owner			= THIS_MODULE,
	.init_tempsel		= __xfrm6_init_tempsel,
	.tmpl_sort		= __xfrm6_tmpl_sort,
	.state_sort		= __xfrm6_state_sort,
	.output			= xfrm6_output,
	.extract_input		= xfrm6_extract_input,
	.extract_output		= xfrm6_extract_output,
	.transport_finish	= xfrm6_transport_finish,
};

int __init xfrm6_state_init(void)
{
	return xfrm_state_register_afinfo(&xfrm6_state_afinfo);
}

void xfrm6_state_fini(void)
{
	xfrm_state_unregister_afinfo(&xfrm6_state_afinfo);
}