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         struct child_sa *sa = NULL, *lsa;
 104         uint32_t child_hash = child_id % array_size(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 %pSU to %pSU",
 143                        &sa->vc->remote.nbma, &vc->remote.nbma);
 144                 nhrp_vc_update(sa->vc, NOTIFY_VC_IPSEC_UPDATE_NBMA);
 145                 abort_migration = sa->vc->abort_migration;
 146         }
 147         if (sa->vc) {
 148                 /* Deattach old VC */
 149                 sa->vc->ipsec--;
 150                 if (!sa->vc->ipsec)
 151                         nhrp_vc_ipsec_reset(sa->vc);
 152                 nhrp_vc_update(sa->vc, NOTIFY_VC_IPSEC_CHANGED);
 153         }
 154
 155         /* Update */
 156         sa->vc = vc;
 157         if (!vc) {
 158                 list_del(&sa->childlist_entry);
 159                 XFREE(MTYPE_NHRP_VC, sa);
 160         }
 161
 162         return abort_migration;
 163 }
 164
 165 void nhrp_vc_notify_add(struct nhrp_vc *vc, struct notifier_block *n,
 166                         notifier_fn_t action)
 167 {
 168         notifier_add(n, &vc->notifier_list, action);
 169 }
 170
 171 void nhrp_vc_notify_del(struct nhrp_vc *vc, struct notifier_block *n)
 172 {
 173         notifier_del(n);
 174         nhrp_vc_check_delete(vc);
 175 }
 176
 177
 178 struct nhrp_vc_iterator_ctx {
 179         void (*cb)(struct nhrp_vc *, void *);
 180         void *ctx;
 181 };
 182
 183 static void nhrp_vc_iterator(struct hash_bucket *b, void *ctx)
 184 {
 185         struct nhrp_vc_iterator_ctx *ic = ctx;
 186         ic->cb(b->data, ic->ctx);
 187 }
 188
 189 void nhrp_vc_foreach(void (*cb)(struct nhrp_vc *, void *), void *ctx)
 190 {
 191         struct nhrp_vc_iterator_ctx ic = {
 192                 .cb = cb, .ctx = ctx,
 193         };
 194         hash_iterate(nhrp_vc_hash, nhrp_vc_iterator, &ic);
 195 }
 196
 197 void nhrp_vc_init(void)
 198 {
 199         size_t i;
 200
 201         nhrp_vc_hash = hash_create(nhrp_vc_key, nhrp_vc_cmp, "NHRP VC hash");
 202         for (i = 0; i < array_size(childlist_head); i++)
 203                 list_init(&childlist_head[i]);
 204 }
 205
 206 void nhrp_vc_reset(void)
 207 {
 208         struct child_sa *sa, *n;
 209         size_t i;
 210
 211         for (i = 0; i < array_size(childlist_head); i++) {
 212                 list_for_each_entry_safe(sa, n, &childlist_head[i],
 213                                          childlist_entry)
 214                         nhrp_vc_ipsec_updown(sa->id, 0);
 215         }
 216 }
 217
 218 void nhrp_vc_terminate(void)
 219 {
 220         nhrp_vc_reset();
 221         hash_clean(nhrp_vc_hash, nhrp_vc_free);
 222 }