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(const void *peer_data)
  32 {
  33         const 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 bool 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
  43         return sockunion_same(&a->local.nbma, &b->local.nbma)
  44                && sockunion_same(&a->remote.nbma, &b->remote.nbma);
  45 }
  46
  47 static void *nhrp_vc_alloc(void *data)
  48 {
  49         struct nhrp_vc *vc, *key = data;
  50
  51         vc = XMALLOC(MTYPE_NHRP_VC, sizeof(struct nhrp_vc));
  52
  53         *vc = (struct nhrp_vc){
  54                 .local.nbma = key->local.nbma,
  55                 .remote.nbma = key->remote.nbma,
  56                 .notifier_list =
  57                 NOTIFIER_LIST_INITIALIZER(&vc->notifier_list),
  58         };
  59
  60         return vc;
  61 }
  62
  63 static void nhrp_vc_free(void *data)
  64 {
  65         XFREE(MTYPE_NHRP_VC, data);
  66 }
  67
  68 struct nhrp_vc *nhrp_vc_get(const union sockunion *src,
  69                             const union sockunion *dst, int create)
  70 {
  71         struct nhrp_vc key;
  72         key.local.nbma = *src;
  73         key.remote.nbma = *dst;
  74         return hash_get(nhrp_vc_hash, &key, create ? nhrp_vc_alloc : 0);
  75 }
  76
  77 static void nhrp_vc_check_delete(struct nhrp_vc *vc)
  78 {
  79         if (vc->updating || vc->ipsec || notifier_active(&vc->notifier_list))
  80                 return;
  81         hash_release(nhrp_vc_hash, vc);
  82         nhrp_vc_free(vc);
  83 }
  84
  85 static void nhrp_vc_update(struct nhrp_vc *vc, long cmd)
  86 {
  87         vc->updating = 1;
  88         notifier_call(&vc->notifier_list, cmd);
  89         vc->updating = 0;
  90         nhrp_vc_check_delete(vc);
  91 }
  92
  93 static void nhrp_vc_ipsec_reset(struct nhrp_vc *vc)
  94 {
  95         vc->local.id[0] = 0;
  96         vc->local.certlen = 0;
  97         vc->remote.id[0] = 0;
  98         vc->remote.certlen = 0;
  99 }
 100
 101 int nhrp_vc_ipsec_updown(uint32_t child_id, struct nhrp_vc *vc)
 102 {
 103         char buf[2][SU_ADDRSTRLEN];
 104         struct child_sa *sa = NULL, *lsa;
 105         uint32_t child_hash = child_id % array_size(childlist_head);
 106         int abort_migration = 0;
 107
 108         list_for_each_entry(lsa, &childlist_head[child_hash], childlist_entry)
 109         {
 110                 if (lsa->id == child_id) {
 111                         sa = lsa;
 112                         break;
 113                 }
 114         }
 115
 116         if (!sa) {
 117                 if (!vc)
 118                         return 0;
 119
 120                 sa = XMALLOC(MTYPE_NHRP_VC, sizeof(struct child_sa));
 121
 122                 *sa = (struct child_sa){
 123                         .id = child_id,
 124                         .childlist_entry =
 125                                 LIST_INITIALIZER(sa->childlist_entry),
 126                         .vc = NULL,
 127                 };
 128                 list_add_tail(&sa->childlist_entry,
 129                               &childlist_head[child_hash]);
 130         }
 131
 132         if (sa->vc == vc)
 133                 return 0;
 134
 135         if (vc) {
 136                 /* Attach first to new VC */
 137                 vc->ipsec++;
 138                 nhrp_vc_update(vc, NOTIFY_VC_IPSEC_CHANGED);
 139         }
 140         if (sa->vc && vc) {
 141                 /* Notify old VC of migration */
 142                 sa->vc->abort_migration = 0;
 143                 debugf(NHRP_DEBUG_COMMON, "IPsec NBMA change of %s to %s",
 144                        sockunion2str(&sa->vc->remote.nbma, buf[0],
 145                                      sizeof(buf[0])),
 146                        sockunion2str(&vc->remote.nbma, buf[1], sizeof(buf[1])));
 147                 nhrp_vc_update(sa->vc, NOTIFY_VC_IPSEC_UPDATE_NBMA);
 148                 abort_migration = sa->vc->abort_migration;
 149         }
 150         if (sa->vc) {
 151                 /* Deattach old VC */
 152                 sa->vc->ipsec--;
 153                 if (!sa->vc->ipsec)
 154                         nhrp_vc_ipsec_reset(sa->vc);
 155                 nhrp_vc_update(sa->vc, NOTIFY_VC_IPSEC_CHANGED);
 156         }
 157
 158         /* Update */
 159         sa->vc = vc;
 160         if (!vc) {
 161                 list_del(&sa->childlist_entry);
 162                 XFREE(MTYPE_NHRP_VC, sa);
 163         }
 164
 165         return abort_migration;
 166 }
 167
 168 void nhrp_vc_notify_add(struct nhrp_vc *vc, struct notifier_block *n,
 169                         notifier_fn_t action)
 170 {
 171         notifier_add(n, &vc->notifier_list, action);
 172 }
 173
 174 void nhrp_vc_notify_del(struct nhrp_vc *vc, struct notifier_block *n)
 175 {
 176         notifier_del(n);
 177         nhrp_vc_check_delete(vc);
 178 }
 179
 180
 181 struct nhrp_vc_iterator_ctx {
 182         void (*cb)(struct nhrp_vc *, void *);
 183         void *ctx;
 184 };
 185
 186 static void nhrp_vc_iterator(struct hash_bucket *b, void *ctx)
 187 {
 188         struct nhrp_vc_iterator_ctx *ic = ctx;
 189         ic->cb(b->data, ic->ctx);
 190 }
 191
 192 void nhrp_vc_foreach(void (*cb)(struct nhrp_vc *, void *), void *ctx)
 193 {
 194         struct nhrp_vc_iterator_ctx ic = {
 195                 .cb = cb, .ctx = ctx,
 196         };
 197         hash_iterate(nhrp_vc_hash, nhrp_vc_iterator, &ic);
 198 }
 199
 200 void nhrp_vc_init(void)
 201 {
 202         size_t i;
 203
 204         nhrp_vc_hash = hash_create(nhrp_vc_key, nhrp_vc_cmp, "NHRP VC hash");
 205         for (i = 0; i < array_size(childlist_head); i++)
 206                 list_init(&childlist_head[i]);
 207 }
 208
 209 void nhrp_vc_reset(void)
 210 {
 211         struct child_sa *sa, *n;
 212         size_t i;
 213
 214         for (i = 0; i < array_size(childlist_head); i++) {
 215                 list_for_each_entry_safe(sa, n, &childlist_head[i],
 216                                          childlist_entry)
 217                         nhrp_vc_ipsec_updown(sa->id, 0);
 218         }
 219 }
 220
 221 void nhrp_vc_terminate(void)
 222 {
 223         nhrp_vc_reset();
 224         hash_clean(nhrp_vc_hash, nhrp_vc_free);
 225 }