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         if (tmpl->mode == XFRM_MODE_TUNNEL && x->props.saddr.a4 == 0) {
  46                 struct rtable *rt;
  47                 struct flowi fl_tunnel = {
  48                         .nl_u = {
  49                                 .ip4_u = {
  50                                         .daddr = x->id.daddr.a4,
  51                                 }
  52                         }
  53                 };
  54                 if (!xfrm_dst_lookup((struct xfrm_dst **)&rt,
  55                                      &fl_tunnel, AF_INET)) {
  56                         x->props.saddr.a4 = rt->rt_src;
  57                         dst_release(&rt->u.dst);
  58                 }
  59         }
  60         x->props.mode = tmpl->mode;
  61         x->props.reqid = tmpl->reqid;
  62         x->props.family = AF_INET;
  63 }
  64
  65 static struct xfrm_state *
  66 __xfrm4_state_lookup(xfrm_address_t *daddr, u32 spi, u8 proto)
  67 {
  68         unsigned h = __xfrm4_spi_hash(daddr, spi, proto);
  69         struct xfrm_state *x;
  70
  71         list_for_each_entry(x, xfrm4_state_afinfo.state_byspi+h, byspi) {
  72                 if (x->props.family == AF_INET &&
  73                     spi == x->id.spi &&
  74                     daddr->a4 == x->id.daddr.a4 &&
  75                     proto == x->id.proto) {
  76                         xfrm_state_hold(x);
  77                         return x;
  78                 }
  79         }
  80         return NULL;
  81 }
  82
  83 /* placeholder until ipv4's code is written */
  84 static struct xfrm_state *
  85 __xfrm4_state_lookup_byaddr(xfrm_address_t *daddr, xfrm_address_t *saddr,
  86                             u8 proto)
  87 {
  88         return NULL;
  89 }
  90
  91 static struct xfrm_state *
  92 __xfrm4_find_acq(u8 mode, u32 reqid, u8 proto,
  93                  xfrm_address_t *daddr, xfrm_address_t *saddr,
  94                  int create)
  95 {
  96         struct xfrm_state *x, *x0;
  97         unsigned h = __xfrm4_dst_hash(daddr);
  98
  99         x0 = NULL;
 100
 101         list_for_each_entry(x, xfrm4_state_afinfo.state_bydst+h, bydst) {
 102                 if (x->props.family == AF_INET &&
 103                     daddr->a4 == x->id.daddr.a4 &&
 104                     mode == x->props.mode &&
 105                     proto == x->id.proto &&
 106                     saddr->a4 == x->props.saddr.a4 &&
 107                     reqid == x->props.reqid &&
 108                     x->km.state == XFRM_STATE_ACQ &&
 109                     !x->id.spi) {
 110                             x0 = x;
 111                             break;
 112                     }
 113         }
 114         if (!x0 && create && (x0 = xfrm_state_alloc()) != NULL) {
 115                 x0->sel.daddr.a4 = daddr->a4;
 116                 x0->sel.saddr.a4 = saddr->a4;
 117                 x0->sel.prefixlen_d = 32;
 118                 x0->sel.prefixlen_s = 32;
 119                 x0->props.saddr.a4 = saddr->a4;
 120                 x0->km.state = XFRM_STATE_ACQ;
 121                 x0->id.daddr.a4 = daddr->a4;
 122                 x0->id.proto = proto;
 123                 x0->props.family = AF_INET;
 124                 x0->props.mode = mode;
 125                 x0->props.reqid = reqid;
 126                 x0->props.family = AF_INET;
 127                 x0->lft.hard_add_expires_seconds = XFRM_ACQ_EXPIRES;
 128                 xfrm_state_hold(x0);
 129                 x0->timer.expires = jiffies + XFRM_ACQ_EXPIRES*HZ;
 130                 add_timer(&x0->timer);
 131                 xfrm_state_hold(x0);
 132                 list_add_tail(&x0->bydst, xfrm4_state_afinfo.state_bydst+h);
 133                 h = __xfrm4_src_hash(saddr);
 134                 xfrm_state_hold(x0);
 135                 list_add_tail(&x0->bysrc, xfrm4_state_afinfo.state_bysrc+h);
 136                 wake_up(&km_waitq);
 137         }
 138         if (x0)
 139                 xfrm_state_hold(x0);
 140         return x0;
 141 }
 142
 143 static struct xfrm_state_afinfo xfrm4_state_afinfo = {
 144         .family                 = AF_INET,
 145         .init_flags             = xfrm4_init_flags,
 146         .init_tempsel           = __xfrm4_init_tempsel,
 147         .state_lookup           = __xfrm4_state_lookup,
 148         .state_lookup_byaddr    = __xfrm4_state_lookup_byaddr,
 149         .find_acq               = __xfrm4_find_acq,
 150 };
 151
 152 void __init xfrm4_state_init(void)
 153 {
 154         xfrm_state_register_afinfo(&xfrm4_state_afinfo);
 155 }
 156
 157 #if 0
 158 void __exit xfrm4_state_fini(void)
 159 {
 160         xfrm_state_unregister_afinfo(&xfrm4_state_afinfo);
 161 }
 162 #endif  /*  0  */
 163