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(
  35                 sockunion_hash(&vc->local.nbma),
  36                 sockunion_hash(&vc->remote.nbma),
  37                 0);
  38 }
  39
  40 static int nhrp_vc_cmp(const void *cache_data, const void *key_data)
  41 {
  42         const struct nhrp_vc *a = cache_data;
  43         const struct nhrp_vc *b = key_data;
  44         return  sockunion_same(&a->local.nbma, &b->local.nbma) &&
  45                 sockunion_same(&a->remote.nbma, &b->remote.nbma);
  46 }
  47
  48 static void *nhrp_vc_alloc(void *data)
  49 {
  50         struct nhrp_vc *vc, *key = data;
  51
  52         vc = XMALLOC(MTYPE_NHRP_VC, sizeof(struct nhrp_vc));
  53         if (vc) {
  54                 *vc = (struct nhrp_vc) {
  55                         .local.nbma = key->local.nbma,
  56                         .remote.nbma = key->remote.nbma,
  57                         .notifier_list = NOTIFIER_LIST_INITIALIZER(&vc->notifier_list),
  58                 };
  59         }
  60
  61         return vc;
  62 }
  63
  64 static void nhrp_vc_free(void *data)
  65 {
  66         XFREE(MTYPE_NHRP_VC, data);
  67 }
  68
  69 struct nhrp_vc *nhrp_vc_get(const union sockunion *src, 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 % ZEBRA_NUM_OF(childlist_head);
 106         int abort_migration = 0;
 107
 108         list_for_each_entry(lsa, &childlist_head[child_hash], childlist_entry) {
 109                 if (lsa->id == child_id) {
 110                         sa = lsa;
 111                         break;
 112                 }
 113         }
 114
 115         if (!sa) {
 116                 if (!vc) return 0;
 117
 118                 sa = XMALLOC(MTYPE_NHRP_VC, sizeof(struct child_sa));
 119                 if (!sa) return 0;
 120
 121                 *sa = (struct child_sa) {
 122                         .id = child_id,
 123                         .childlist_entry = LIST_INITIALIZER(sa->childlist_entry),
 124                         .vc = NULL,
 125                 };
 126                 list_add_tail(&sa->childlist_entry, &childlist_head[child_hash]);
 127         }
 128
 129         if (sa->vc == vc)
 130                 return 0;
 131
 132         if (vc) {
 133                 /* Attach first to new VC */
 134                 vc->ipsec++;
 135                 nhrp_vc_update(vc, NOTIFY_VC_IPSEC_CHANGED);
 136         }
 137         if (sa->vc && vc) {
 138                 /* Notify old VC of migration */
 139                 sa->vc->abort_migration = 0;
 140                 debugf(NHRP_DEBUG_COMMON, "IPsec NBMA change of %s to %s",
 141                         sockunion2str(&sa->vc->remote.nbma, buf[0], sizeof buf[0]),
 142                         sockunion2str(&vc->remote.nbma, buf[1], sizeof buf[1]));
 143                 nhrp_vc_update(sa->vc, NOTIFY_VC_IPSEC_UPDATE_NBMA);
 144                 abort_migration = sa->vc->abort_migration;
 145         }
 146         if (sa->vc) {
 147                 /* Deattach old VC */
 148                 sa->vc->ipsec--;
 149                 if (!sa->vc->ipsec) nhrp_vc_ipsec_reset(sa->vc);
 150                 nhrp_vc_update(sa->vc, NOTIFY_VC_IPSEC_CHANGED);
 151         }
 152
 153         /* Update */
 154         sa->vc = vc;
 155         if (!vc) {
 156                 list_del(&sa->childlist_entry);
 157                 XFREE(MTYPE_NHRP_VC, sa);
 158         }
 159
 160         return abort_migration;
 161 }
 162
 163 void nhrp_vc_notify_add(struct nhrp_vc *vc, struct notifier_block *n, notifier_fn_t action)
 164 {
 165         notifier_add(n, &vc->notifier_list, action);
 166 }
 167
 168 void nhrp_vc_notify_del(struct nhrp_vc *vc, struct notifier_block *n)
 169 {
 170         notifier_del(n);
 171         nhrp_vc_check_delete(vc);
 172 }
 173
 174
 175 struct nhrp_vc_iterator_ctx {
 176         void (*cb)(struct nhrp_vc *, void *);
 177         void *ctx;
 178 };
 179
 180 static void nhrp_vc_iterator(struct hash_backet *b, void *ctx)
 181 {
 182         struct nhrp_vc_iterator_ctx *ic = ctx;
 183         ic->cb(b->data, ic->ctx);
 184 }
 185
 186 void nhrp_vc_foreach(void (*cb)(struct nhrp_vc *, void *), void *ctx)
 187 {
 188         struct nhrp_vc_iterator_ctx ic = {
 189                 .cb = cb,
 190                 .ctx = ctx,
 191         };
 192         hash_iterate(nhrp_vc_hash, nhrp_vc_iterator, &ic);
 193 }
 194
 195 void nhrp_vc_init(void)
 196 {
 197         size_t i;
 198
 199         nhrp_vc_hash = hash_create(nhrp_vc_key,
 200                                    nhrp_vc_cmp,
 201                                    "NHRP VC hash");
 202         for (i = 0; i < ZEBRA_NUM_OF(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 < ZEBRA_NUM_OF(childlist_head); i++) {
 212                 list_for_each_entry_safe(sa, n, &childlist_head[i], childlist_entry)
 213                         nhrp_vc_ipsec_updown(sa->id, 0);
 214         }
 215 }
 216
 217 void nhrp_vc_terminate(void)
 218 {
 219         nhrp_vc_reset();
 220         hash_clean(nhrp_vc_hash, nhrp_vc_free);
 221 }