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