[IPSEC]: Add XFRM_STATE_NOPMTUDISC flag
[linux-2.6.git] / net / ipv4 / xfrm4_state.c
1 /*
2  * xfrm4_state.c
3  *
4  * Changes:
5  *      YOSHIFUJI Hideaki @USAGI
6  *              Split up af-specific portion
7  *
8  */
9
10 #include <net/ip.h>
11 #include <net/xfrm.h>
12 #include <linux/pfkeyv2.h>
13 #include <linux/ipsec.h>
14
15 static struct xfrm_state_afinfo xfrm4_state_afinfo;
16
17 static int xfrm4_init_flags(struct xfrm_state *x)
18 {
19         if (ipv4_config.no_pmtu_disc)
20                 x->props.flags |= XFRM_STATE_NOPMTUDISC;
21         return 0;
22 }
23
24 static void
25 __xfrm4_init_tempsel(struct xfrm_state *x, struct flowi *fl,
26                      struct xfrm_tmpl *tmpl,
27                      xfrm_address_t *daddr, xfrm_address_t *saddr)
28 {
29         x->sel.daddr.a4 = fl->fl4_dst;
30         x->sel.saddr.a4 = fl->fl4_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 = 32;
36         x->sel.prefixlen_s = 32;
37         x->sel.proto = fl->proto;
38         x->sel.ifindex = fl->oif;
39         x->id = tmpl->id;
40         if (x->id.daddr.a4 == 0)
41                 x->id.daddr.a4 = daddr->a4;
42         x->props.saddr = tmpl->saddr;
43         if (x->props.saddr.a4 == 0)
44                 x->props.saddr.a4 = saddr->a4;
45         x->props.mode = tmpl->mode;
46         x->props.reqid = tmpl->reqid;
47         x->props.family = AF_INET;
48 }
49
50 static struct xfrm_state *
51 __xfrm4_state_lookup(xfrm_address_t *daddr, u32 spi, u8 proto)
52 {
53         unsigned h = __xfrm4_spi_hash(daddr, spi, proto);
54         struct xfrm_state *x;
55
56         list_for_each_entry(x, xfrm4_state_afinfo.state_byspi+h, byspi) {
57                 if (x->props.family == AF_INET &&
58                     spi == x->id.spi &&
59                     daddr->a4 == x->id.daddr.a4 &&
60                     proto == x->id.proto) {
61                         xfrm_state_hold(x);
62                         return x;
63                 }
64         }
65         return NULL;
66 }
67
68 static struct xfrm_state *
69 __xfrm4_find_acq(u8 mode, u32 reqid, u8 proto, 
70                  xfrm_address_t *daddr, xfrm_address_t *saddr, 
71                  int create)
72 {
73         struct xfrm_state *x, *x0;
74         unsigned h = __xfrm4_dst_hash(daddr);
75
76         x0 = NULL;
77
78         list_for_each_entry(x, xfrm4_state_afinfo.state_bydst+h, bydst) {
79                 if (x->props.family == AF_INET &&
80                     daddr->a4 == x->id.daddr.a4 &&
81                     mode == x->props.mode &&
82                     proto == x->id.proto &&
83                     saddr->a4 == x->props.saddr.a4 &&
84                     reqid == x->props.reqid &&
85                     x->km.state == XFRM_STATE_ACQ &&
86                     !x->id.spi) {
87                             x0 = x;
88                             break;
89                     }
90         }
91         if (!x0 && create && (x0 = xfrm_state_alloc()) != NULL) {
92                 x0->sel.daddr.a4 = daddr->a4;
93                 x0->sel.saddr.a4 = saddr->a4;
94                 x0->sel.prefixlen_d = 32;
95                 x0->sel.prefixlen_s = 32;
96                 x0->props.saddr.a4 = saddr->a4;
97                 x0->km.state = XFRM_STATE_ACQ;
98                 x0->id.daddr.a4 = daddr->a4;
99                 x0->id.proto = proto;
100                 x0->props.family = AF_INET;
101                 x0->props.mode = mode;
102                 x0->props.reqid = reqid;
103                 x0->props.family = AF_INET;
104                 x0->lft.hard_add_expires_seconds = XFRM_ACQ_EXPIRES;
105                 xfrm_state_hold(x0);
106                 x0->timer.expires = jiffies + XFRM_ACQ_EXPIRES*HZ;
107                 add_timer(&x0->timer);
108                 xfrm_state_hold(x0);
109                 list_add_tail(&x0->bydst, xfrm4_state_afinfo.state_bydst+h);
110                 wake_up(&km_waitq);
111         }
112         if (x0)
113                 xfrm_state_hold(x0);
114         return x0;
115 }
116
117 static struct xfrm_state_afinfo xfrm4_state_afinfo = {
118         .family                 = AF_INET,
119         .lock                   = RW_LOCK_UNLOCKED,
120         .init_flags             = xfrm4_init_flags,
121         .init_tempsel           = __xfrm4_init_tempsel,
122         .state_lookup           = __xfrm4_state_lookup,
123         .find_acq               = __xfrm4_find_acq,
124 };
125
126 void __init xfrm4_state_init(void)
127 {
128         xfrm_state_register_afinfo(&xfrm4_state_afinfo);
129 }
130
131 void __exit xfrm4_state_fini(void)
132 {
133         xfrm_state_unregister_afinfo(&xfrm4_state_afinfo);
134 }
135