net/ipv6/xfrm6_state.c

   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 == XFRM_MODE_TUNNEL && 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 int
  67 __xfrm6_state_sort(struct xfrm_state **dst, struct xfrm_state **src, int n)
  68 {
  69         int i;
  70         int j = 0;
  71
  72         /* Rule 1: select IPsec transport except AH */
  73         for (i = 0; i < n; i++) {
  74                 if (src[i]->props.mode == XFRM_MODE_TRANSPORT &&
  75                     src[i]->id.proto != IPPROTO_AH) {
  76                         dst[j++] = src[i];
  77                         src[i] = NULL;
  78                 }
  79         }
  80         if (j == n)
  81                 goto end;
  82
  83         /* Rule 2: select MIPv6 RO or inbound trigger */
  84 #ifdef CONFIG_IPV6_MIP6
  85         for (i = 0; i < n; i++) {
  86                 if (src[i] &&
  87                     (src[i]->props.mode == XFRM_MODE_ROUTEOPTIMIZATION ||
  88                      src[i]->props.mode == XFRM_MODE_IN_TRIGGER)) {
  89                         dst[j++] = src[i];
  90                         src[i] = NULL;
  91                 }
  92         }
  93         if (j == n)
  94                 goto end;
  95 #endif
  96
  97         /* Rule 3: select IPsec transport AH */
  98         for (i = 0; i < n; i++) {
  99                 if (src[i] &&
 100                     src[i]->props.mode == XFRM_MODE_TRANSPORT &&
 101                     src[i]->id.proto == IPPROTO_AH) {
 102                         dst[j++] = src[i];
 103                         src[i] = NULL;
 104                 }
 105         }
 106         if (j == n)
 107                 goto end;
 108
 109         /* Rule 4: select IPsec tunnel */
 110         for (i = 0; i < n; i++) {
 111                 if (src[i] &&
 112                     src[i]->props.mode == XFRM_MODE_TUNNEL) {
 113                         dst[j++] = src[i];
 114                         src[i] = NULL;
 115                 }
 116         }
 117         if (likely(j == n))
 118                 goto end;
 119
 120         /* Final rule */
 121         for (i = 0; i < n; i++) {
 122                 if (src[i]) {
 123                         dst[j++] = src[i];
 124                         src[i] = NULL;
 125                 }
 126         }
 127
 128  end:
 129         return 0;
 130 }
 131
 132 static int
 133 __xfrm6_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src, int n)
 134 {
 135         int i;
 136         int j = 0;
 137
 138         /* Rule 1: select IPsec transport */
 139         for (i = 0; i < n; i++) {
 140                 if (src[i]->mode == XFRM_MODE_TRANSPORT) {
 141                         dst[j++] = src[i];
 142                         src[i] = NULL;
 143                 }
 144         }
 145         if (j == n)
 146                 goto end;
 147
 148         /* Rule 2: select MIPv6 RO or inbound trigger */
 149 #ifdef CONFIG_IPV6_MIP6
 150         for (i = 0; i < n; i++) {
 151                 if (src[i] &&
 152                     (src[i]->mode == XFRM_MODE_ROUTEOPTIMIZATION ||
 153                      src[i]->mode == XFRM_MODE_IN_TRIGGER)) {
 154                         dst[j++] = src[i];
 155                         src[i] = NULL;
 156                 }
 157         }
 158         if (j == n)
 159                 goto end;
 160 #endif
 161
 162         /* Rule 3: select IPsec tunnel */
 163         for (i = 0; i < n; i++) {
 164                 if (src[i] &&
 165                     src[i]->mode == XFRM_MODE_TUNNEL) {
 166                         dst[j++] = src[i];
 167                         src[i] = NULL;
 168                 }
 169         }
 170         if (likely(j == n))
 171                 goto end;
 172
 173         /* Final rule */
 174         for (i = 0; i < n; i++) {
 175                 if (src[i]) {
 176                         dst[j++] = src[i];
 177                         src[i] = NULL;
 178                 }
 179         }
 180
 181  end:
 182         return 0;
 183 }
 184
 185 static struct xfrm_state_afinfo xfrm6_state_afinfo = {
 186         .family                 = AF_INET6,
 187         .init_tempsel           = __xfrm6_init_tempsel,
 188         .tmpl_sort              = __xfrm6_tmpl_sort,
 189         .state_sort             = __xfrm6_state_sort,
 190 };
 191
 192 void __init xfrm6_state_init(void)
 193 {
 194         xfrm_state_register_afinfo(&xfrm6_state_afinfo);
 195 }
 196
 197 void xfrm6_state_fini(void)
 198 {
 199         xfrm_state_unregister_afinfo(&xfrm6_state_afinfo);
 200 }
 201