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 = htons(0xffff);
  33         x->sel.sport = xfrm_flowi_sport(fl);
  34         x->sel.sport_mask = htons(0xffff);
  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         x->props.mode = tmpl->mode;
  46         x->props.reqid = tmpl->reqid;
  47         x->props.family = AF_INET6;
  48 }
  49
  50 static int
  51 __xfrm6_state_sort(struct xfrm_state **dst, struct xfrm_state **src, int n)
  52 {
  53         int i;
  54         int j = 0;
  55
  56         /* Rule 1: select IPsec transport except AH */
  57         for (i = 0; i < n; i++) {
  58                 if (src[i]->props.mode == XFRM_MODE_TRANSPORT &&
  59                     src[i]->id.proto != IPPROTO_AH) {
  60                         dst[j++] = src[i];
  61                         src[i] = NULL;
  62                 }
  63         }
  64         if (j == n)
  65                 goto end;
  66
  67         /* Rule 2: select MIPv6 RO or inbound trigger */
  68 #ifdef CONFIG_IPV6_MIP6
  69         for (i = 0; i < n; i++) {
  70                 if (src[i] &&
  71                     (src[i]->props.mode == XFRM_MODE_ROUTEOPTIMIZATION ||
  72                      src[i]->props.mode == XFRM_MODE_IN_TRIGGER)) {
  73                         dst[j++] = src[i];
  74                         src[i] = NULL;
  75                 }
  76         }
  77         if (j == n)
  78                 goto end;
  79 #endif
  80
  81         /* Rule 3: select IPsec transport AH */
  82         for (i = 0; i < n; i++) {
  83                 if (src[i] &&
  84                     src[i]->props.mode == XFRM_MODE_TRANSPORT &&
  85                     src[i]->id.proto == IPPROTO_AH) {
  86                         dst[j++] = src[i];
  87                         src[i] = NULL;
  88                 }
  89         }
  90         if (j == n)
  91                 goto end;
  92
  93         /* Rule 4: select IPsec tunnel */
  94         for (i = 0; i < n; i++) {
  95                 if (src[i] &&
  96                     src[i]->props.mode == XFRM_MODE_TUNNEL) {
  97                         dst[j++] = src[i];
  98                         src[i] = NULL;
  99                 }
 100         }
 101         if (likely(j == n))
 102                 goto end;
 103
 104         /* Final rule */
 105         for (i = 0; i < n; i++) {
 106                 if (src[i]) {
 107                         dst[j++] = src[i];
 108                         src[i] = NULL;
 109                 }
 110         }
 111
 112  end:
 113         return 0;
 114 }
 115
 116 static int
 117 __xfrm6_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src, int n)
 118 {
 119         int i;
 120         int j = 0;
 121
 122         /* Rule 1: select IPsec transport */
 123         for (i = 0; i < n; i++) {
 124                 if (src[i]->mode == XFRM_MODE_TRANSPORT) {
 125                         dst[j++] = src[i];
 126                         src[i] = NULL;
 127                 }
 128         }
 129         if (j == n)
 130                 goto end;
 131
 132         /* Rule 2: select MIPv6 RO or inbound trigger */
 133 #ifdef CONFIG_IPV6_MIP6
 134         for (i = 0; i < n; i++) {
 135                 if (src[i] &&
 136                     (src[i]->mode == XFRM_MODE_ROUTEOPTIMIZATION ||
 137                      src[i]->mode == XFRM_MODE_IN_TRIGGER)) {
 138                         dst[j++] = src[i];
 139                         src[i] = NULL;
 140                 }
 141         }
 142         if (j == n)
 143                 goto end;
 144 #endif
 145
 146         /* Rule 3: select IPsec tunnel */
 147         for (i = 0; i < n; i++) {
 148                 if (src[i] &&
 149                     src[i]->mode == XFRM_MODE_TUNNEL) {
 150                         dst[j++] = src[i];
 151                         src[i] = NULL;
 152                 }
 153         }
 154         if (likely(j == n))
 155                 goto end;
 156
 157         /* Final rule */
 158         for (i = 0; i < n; i++) {
 159                 if (src[i]) {
 160                         dst[j++] = src[i];
 161                         src[i] = NULL;
 162                 }
 163         }
 164
 165  end:
 166         return 0;
 167 }
 168
 169 static struct xfrm_state_afinfo xfrm6_state_afinfo = {
 170         .family                 = AF_INET6,
 171         .init_tempsel           = __xfrm6_init_tempsel,
 172         .tmpl_sort              = __xfrm6_tmpl_sort,
 173         .state_sort             = __xfrm6_state_sort,
 174         .output                 = xfrm6_output,
 175 };
 176
 177 void __init xfrm6_state_init(void)
 178 {
 179         xfrm_state_register_afinfo(&xfrm6_state_afinfo);
 180 }
 181
 182 void xfrm6_state_fini(void)
 183 {
 184         xfrm_state_unregister_afinfo(&xfrm6_state_afinfo);
 185 }
 186