xref: /linux/net/ipv6/xfrm6_state.c (revision f3d9478b2ce468c3115b02ecae7e975990697f15)
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 
20 static struct xfrm_state_afinfo xfrm6_state_afinfo;
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 = ~0;
33 	x->sel.sport = xfrm_flowi_sport(fl);
34 	x->sel.sport_mask = ~0;
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 	if (tmpl->mode && ipv6_addr_any((struct in6_addr*)&x->props.saddr)) {
46 		struct rt6_info *rt;
47 		struct flowi fl_tunnel = {
48 			.nl_u = {
49 				.ip6_u = {
50 					.daddr = *(struct in6_addr *)daddr,
51 				}
52 			}
53 		};
54 		if (!xfrm_dst_lookup((struct xfrm_dst **)&rt,
55 		                     &fl_tunnel, AF_INET6)) {
56 			ipv6_get_saddr(&rt->u.dst, (struct in6_addr *)daddr,
57 			               (struct in6_addr *)&x->props.saddr);
58 			dst_release(&rt->u.dst);
59 		}
60 	}
61 	x->props.mode = tmpl->mode;
62 	x->props.reqid = tmpl->reqid;
63 	x->props.family = AF_INET6;
64 }
65 
66 static struct xfrm_state *
67 __xfrm6_state_lookup(xfrm_address_t *daddr, u32 spi, u8 proto)
68 {
69 	unsigned h = __xfrm6_spi_hash(daddr, spi, proto);
70 	struct xfrm_state *x;
71 
72 	list_for_each_entry(x, xfrm6_state_afinfo.state_byspi+h, byspi) {
73 		if (x->props.family == AF_INET6 &&
74 		    spi == x->id.spi &&
75 		    ipv6_addr_equal((struct in6_addr *)daddr, (struct in6_addr *)x->id.daddr.a6) &&
76 		    proto == x->id.proto) {
77 			xfrm_state_hold(x);
78 			return x;
79 		}
80 	}
81 	return NULL;
82 }
83 
84 static struct xfrm_state *
85 __xfrm6_find_acq(u8 mode, u32 reqid, u8 proto,
86 		 xfrm_address_t *daddr, xfrm_address_t *saddr,
87 		 int create)
88 {
89 	struct xfrm_state *x, *x0;
90 	unsigned h = __xfrm6_dst_hash(daddr);
91 
92 	x0 = NULL;
93 
94 	list_for_each_entry(x, xfrm6_state_afinfo.state_bydst+h, bydst) {
95 		if (x->props.family == AF_INET6 &&
96 		    ipv6_addr_equal((struct in6_addr *)daddr, (struct in6_addr *)x->id.daddr.a6) &&
97 		    mode == x->props.mode &&
98 		    proto == x->id.proto &&
99 		    ipv6_addr_equal((struct in6_addr *)saddr, (struct in6_addr *)x->props.saddr.a6) &&
100 		    reqid == x->props.reqid &&
101 		    x->km.state == XFRM_STATE_ACQ &&
102 		    !x->id.spi) {
103 			    x0 = x;
104 			    break;
105 		    }
106 	}
107 	if (!x0 && create && (x0 = xfrm_state_alloc()) != NULL) {
108 		ipv6_addr_copy((struct in6_addr *)x0->sel.daddr.a6,
109 			       (struct in6_addr *)daddr);
110 		ipv6_addr_copy((struct in6_addr *)x0->sel.saddr.a6,
111 			       (struct in6_addr *)saddr);
112 		x0->sel.prefixlen_d = 128;
113 		x0->sel.prefixlen_s = 128;
114 		ipv6_addr_copy((struct in6_addr *)x0->props.saddr.a6,
115 			       (struct in6_addr *)saddr);
116 		x0->km.state = XFRM_STATE_ACQ;
117 		ipv6_addr_copy((struct in6_addr *)x0->id.daddr.a6,
118 			       (struct in6_addr *)daddr);
119 		x0->id.proto = proto;
120 		x0->props.family = AF_INET6;
121 		x0->props.mode = mode;
122 		x0->props.reqid = reqid;
123 		x0->lft.hard_add_expires_seconds = XFRM_ACQ_EXPIRES;
124 		xfrm_state_hold(x0);
125 		x0->timer.expires = jiffies + XFRM_ACQ_EXPIRES*HZ;
126 		add_timer(&x0->timer);
127 		xfrm_state_hold(x0);
128 		list_add_tail(&x0->bydst, xfrm6_state_afinfo.state_bydst+h);
129 		wake_up(&km_waitq);
130 	}
131 	if (x0)
132 		xfrm_state_hold(x0);
133 	return x0;
134 }
135 
136 static struct xfrm_state_afinfo xfrm6_state_afinfo = {
137 	.family			= AF_INET6,
138 	.init_tempsel		= __xfrm6_init_tempsel,
139 	.state_lookup		= __xfrm6_state_lookup,
140 	.find_acq		= __xfrm6_find_acq,
141 };
142 
143 void __init xfrm6_state_init(void)
144 {
145 	xfrm_state_register_afinfo(&xfrm6_state_afinfo);
146 }
147 
148 void xfrm6_state_fini(void)
149 {
150 	xfrm_state_unregister_afinfo(&xfrm6_state_afinfo);
151 }
152 
153