aboutsummaryrefslogtreecommitdiffstats
path: root/net/ipv6/xfrm6_state.c
blob: 8a1f9c0d2a13b27ae0b67c9eacf802f30e656115 (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
/*
 * 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 <linux/export.h>
#include <net/dsfield.h>
#include <net/ipv6.h>
#include <net/addrconf.h>

static void
__xfrm6_init_tempsel(struct xfrm_selector *sel, const struct flowi *fl)
{
	const struct flowi6 *fl6 = &fl->u.ip6;

	/* Initialize temporary selector matching only
	 * to current session. */
	*(struct in6_addr *)&sel->daddr = fl6->daddr;
	*(struct in6_addr *)&sel->saddr = fl6->saddr;
	sel->dport = xfrm_flowi_dport(fl, &fl6->uli);
	sel->dport_mask = htons(0xffff);
	sel->sport = xfrm_flowi_sport(fl, &fl6->uli);
	sel->sport_mask = htons(0xffff);
	sel->family = AF_INET6;
	sel->prefixlen_d = 128;
	sel->prefixlen_s = 128;
	sel->proto = fl6->flowi6_proto;
	sel->ifindex = fl6->flowi6_oif;
}

static void
xfrm6_init_temprop(struct xfrm_state *x, const struct xfrm_tmpl *tmpl,
		   const xfrm_address_t *daddr, const xfrm_address_t *saddr)
{
	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;
}

/* distribution counting sort function for xfrm_state and xfrm_tmpl */
static int
__xfrm6_sort(void **dst, void **src, int n, int (*cmp)(void *p), int maxclass)
{
	int i;
	int class[XFRM_MAX_DEPTH];
	int count[maxclass];

	memset(count, 0, sizeof(count));

	for (i = 0; i < n; i++) {
		int c;
		class[i] = c = cmp(src[i]);
		count[c]++;
	}

	for (i = 2; i < maxclass; i++)
		count[i] += count[i - 1];

	for (i = 0; i < n; i++) {
		dst[count[class[i] - 1]++] = src[i];
		src[i] = NULL;
	}

	return 0;
}

/*
 * Rule for xfrm_state:
 *
 * rule 1: select IPsec transport except AH
 * rule 2: select MIPv6 RO or inbound trigger
 * rule 3: select IPsec transport AH
 * rule 4: select IPsec tunnel
 * rule 5: others
 */
static int __xfrm6_state_sort_cmp(void *p)
{
	struct xfrm_state *v = p;

	switch (v->props.mode) {
	case XFRM_MODE_TRANSPORT:
		if (v->id.proto != IPPROTO_AH)
			return 1;
		else
			return 3;
#if IS_ENABLED(CONFIG_IPV6_MIP6)
	case XFRM_MODE_ROUTEOPTIMIZATION:
	case XFRM_MODE_IN_TRIGGER:
		return 2;
#endif
	case XFRM_MODE_TUNNEL:
	case XFRM_MODE_BEET:
		return 4;
	}
	return 5;
}

static int
__xfrm6_state_sort(struct xfrm_state **dst, struct xfrm_state **src, int n)
{
	return __xfrm6_sort((void **)dst, (void **)src, n,
			    __xfrm6_state_sort_cmp, 6);
}

/*
 * Rule for xfrm_tmpl:
 *
 * rule 1: select IPsec transport
 * rule 2: select MIPv6 RO or inbound trigger
 * rule 3: select IPsec tunnel
 * rule 4: others
 */
static int __xfrm6_tmpl_sort_cmp(void *p)
{
	struct xfrm_tmpl *v = p;
	switch (v->mode) {
	case XFRM_MODE_TRANSPORT:
		return 1;
#if IS_ENABLED(CONFIG_IPV6_MIP6)
	case XFRM_MODE_ROUTEOPTIMIZATION:
	case XFRM_MODE_IN_TRIGGER:
		return 2;
#endif
	case XFRM_MODE_TUNNEL:
	case XFRM_MODE_BEET:
		return 3;
	}
	return 4;
}

static int
__xfrm6_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src, int n)
{
	return __xfrm6_sort((void **)dst, (void **)src, n,
			    __xfrm6_tmpl_sort_cmp, 5);
}

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,
	.init_temprop		= xfrm6_init_temprop,
	.tmpl_sort		= __xfrm6_tmpl_sort,
	.state_sort		= __xfrm6_state_sort,
	.output			= xfrm6_output,
	.output_finish		= xfrm6_output_finish,
	.extract_input		= xfrm6_extract_input,
	.extract_output		= xfrm6_extract_output,
	.transport_finish	= xfrm6_transport_finish,
	.local_error		= xfrm6_local_error,
};

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);
}