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
20static struct xfrm_state_afinfo xfrm6_state_afinfo;
21
22static 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
50static 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
116static 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
169static 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	.output			= xfrm6_output,
175};
176
177void __init xfrm6_state_init(void)
178{
179	xfrm_state_register_afinfo(&xfrm6_state_afinfo);
180}
181
182void xfrm6_state_fini(void)
183{
184	xfrm_state_unregister_afinfo(&xfrm6_state_afinfo);
185}
186