nhrpd/nhrp_vc.c

   1 /* NHRP virtual connection
   2  * Copyright (c) 2014-2015 Timo Teräs
   3  *
   4  * This file is free software: you may copy, redistribute and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 2 of the License, or
   7  * (at your option) any later version.
   8  */
   9
  10 #include "zebra.h"
  11 #include "memory.h"
  12 #include "stream.h"
  13 #include "hash.h"
  14 #include "thread.h"
  15 #include "jhash.h"
  16
  17 #include "nhrpd.h"
  18 #include "os.h"
  19
  20 DEFINE_MTYPE_STATIC(NHRPD, NHRP_VC, "NHRP virtual connection")
  21
  22 struct child_sa {
  23         uint32_t id;
  24         struct nhrp_vc *vc;
  25         struct list_head childlist_entry;
  26 };
  27
  28 static struct hash *nhrp_vc_hash;
  29 static struct list_head childlist_head[512];
  30
  31 static unsigned int nhrp_vc_key(void *peer_data)
  32 {
  33         struct nhrp_vc *vc = peer_data;
  34         return jhash_2words(sockunion_hash(&vc->local.nbma),
  35                             sockunion_hash(&vc->remote.nbma), 0);
  36 }
  37
  38 static int nhrp_vc_cmp(const void *cache_data, const void *key_data)
  39 {
  40         const struct nhrp_vc *a = cache_data;
  41         const struct nhrp_vc *b = key_data;
  42         return sockunion_same(&a->local.nbma, &b->local.nbma)
  43                && sockunion_same(&a->remote.nbma, &b->remote.nbma);
  44 }
  45
  46 static void *nhrp_vc_alloc(void *data)
  47 {
  48         struct nhrp_vc *vc, *key = data;
  49
  50         vc = XMALLOC(MTYPE_NHRP_VC, sizeof(struct nhrp_vc));
  51
  52         *vc = (struct nhrp_vc){
  53                 .local.nbma = key->local.nbma,
  54                 .remote.nbma = key->remote.nbma,
  55                 .notifier_list =
  56                 NOTIFIER_LIST_INITIALIZER(&vc->notifier_list),
  57         };
  58
  59         return vc;
  60 }
  61
  62 static void nhrp_vc_free(void *data)
  63 {
  64         XFREE(MTYPE_NHRP_VC, data);
  65 }
  66
  67 struct nhrp_vc *nhrp_vc_get(const union sockunion *src,
  68                             const union sockunion *dst, int create)
  69 {
  70         struct nhrp_vc key;
  71         key.local.nbma = *src;
  72         key.remote.nbma = *dst;
  73         return hash_get(nhrp_vc_hash, &key, create ? nhrp_vc_alloc : 0);
  74 }
  75
  76 static void nhrp_vc_check_delete(struct nhrp_vc *vc)
  77 {
  78         if (vc->updating || vc->ipsec || notifier_active(&vc->notifier_list))
  79                 return;
  80         hash_release(nhrp_vc_hash, vc);
  81         nhrp_vc_free(vc);
  82 }
  83
  84 static void nhrp_vc_update(struct nhrp_vc *vc, long cmd)
  85 {
  86         vc->updating = 1;
  87         notifier_call(&vc->notifier_list, cmd);
  88         vc->updating = 0;
  89         nhrp_vc_check_delete(vc);
  90 }
  91
  92 static void nhrp_vc_ipsec_reset(struct nhrp_vc *vc)
  93 {
  94         vc->local.id[0] = 0;
  95         vc->local.certlen = 0;
  96         vc->remote.id[0] = 0;
  97         vc->remote.certlen = 0;
  98 }
  99
 100 int nhrp_vc_ipsec_updown(uint32_t child_id, struct nhrp_vc *vc)
 101 {
 102         char buf[2][SU_ADDRSTRLEN];
 103         struct child_sa *sa = NULL, *lsa;
 104         uint32_t child_hash = child_id % ZEBRA_NUM_OF(childlist_head);
 105         int abort_migration = 0;
 106
 107         list_for_each_entry(lsa, &childlist_head[child_hash], childlist_entry)
 108         {
 109                 if (lsa->id == child_id) {
 110                         sa = lsa;
 111                         break;
 112                 }
 113         }
 114
 115         if (!sa) {
 116                 if (!vc)
 117                         return 0;
 118
 119                 sa = XMALLOC(MTYPE_NHRP_VC, sizeof(struct child_sa));
 120
 121                 *sa = (struct child_sa){
 122                         .id = child_id,
 123                         .childlist_entry =
 124                                 LIST_INITIALIZER(sa->childlist_entry),
 125                         .vc = NULL,
 126                 };
 127                 list_add_tail(&sa->childlist_entry,
 128                               &childlist_head[child_hash]);
 129         }
 130
 131         if (sa->vc == vc)
 132                 return 0;
 133
 134         if (vc) {
 135                 /* Attach first to new VC */
 136                 vc->ipsec++;
 137                 nhrp_vc_update(vc, NOTIFY_VC_IPSEC_CHANGED);
 138         }
 139         if (sa->vc && vc) {
 140                 /* Notify old VC of migration */
 141                 sa->vc->abort_migration = 0;
 142                 debugf(NHRP_DEBUG_COMMON, "IPsec NBMA change of %s to %s",
 143                        sockunion2str(&sa->vc->remote.nbma, buf[0],
 144                                      sizeof buf[0]),
 145                        sockunion2str(&vc->remote.nbma, buf[1], sizeof buf[1]));
 146                 nhrp_vc_update(sa->vc, NOTIFY_VC_IPSEC_UPDATE_NBMA);
 147                 abort_migration = sa->vc->abort_migration;
 148         }
 149         if (sa->vc) {
 150                 /* Deattach old VC */
 151                 sa->vc->ipsec--;
 152                 if (!sa->vc->ipsec)
 153                         nhrp_vc_ipsec_reset(sa->vc);
 154                 nhrp_vc_update(sa->vc, NOTIFY_VC_IPSEC_CHANGED);
 155         }
 156
 157         /* Update */
 158         sa->vc = vc;
 159         if (!vc) {
 160                 list_del(&sa->childlist_entry);
 161                 XFREE(MTYPE_NHRP_VC, sa);
 162         }
 163
 164         return abort_migration;
 165 }
 166
 167 void nhrp_vc_notify_add(struct nhrp_vc *vc, struct notifier_block *n,
 168                         notifier_fn_t action)
 169 {
 170         notifier_add(n, &vc->notifier_list, action);
 171 }
 172
 173 void nhrp_vc_notify_del(struct nhrp_vc *vc, struct notifier_block *n)
 174 {
 175         notifier_del(n);
 176         nhrp_vc_check_delete(vc);
 177 }
 178
 179
 180 struct nhrp_vc_iterator_ctx {
 181         void (*cb)(struct nhrp_vc *, void *);
 182         void *ctx;
 183 };
 184
 185 static void nhrp_vc_iterator(struct hash_backet *b, void *ctx)
 186 {
 187         struct nhrp_vc_iterator_ctx *ic = ctx;
 188         ic->cb(b->data, ic->ctx);
 189 }
 190
 191 void nhrp_vc_foreach(void (*cb)(struct nhrp_vc *, void *), void *ctx)
 192 {
 193         struct nhrp_vc_iterator_ctx ic = {
 194                 .cb = cb, .ctx = ctx,
 195         };
 196         hash_iterate(nhrp_vc_hash, nhrp_vc_iterator, &ic);
 197 }
 198
 199 void nhrp_vc_init(void)
 200 {
 201         size_t i;
 202
 203         nhrp_vc_hash = hash_create(nhrp_vc_key, nhrp_vc_cmp, "NHRP VC hash");
 204         for (i = 0; i < ZEBRA_NUM_OF(childlist_head); i++)
 205                 list_init(&childlist_head[i]);
 206 }
 207
 208 void nhrp_vc_reset(void)
 209 {
 210         struct child_sa *sa, *n;
 211         size_t i;
 212
 213         for (i = 0; i < ZEBRA_NUM_OF(childlist_head); i++) {
 214                 list_for_each_entry_safe(sa, n, &childlist_head[i],
 215                                          childlist_entry)
 216                         nhrp_vc_ipsec_updown(sa->id, 0);
 217         }
 218 }
 219
 220 void nhrp_vc_terminate(void)
 221 {
 222         nhrp_vc_reset();
 223         hash_clean(nhrp_vc_hash, nhrp_vc_free);
 224 }