ospfd/ospf_network.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * OSPF network related functions
   4  *   Copyright (C) 1999 Toshiaki Takada
   5  */
   6
   7 #include <zebra.h>
   8
   9 #include "frrevent.h"
  10 #include "linklist.h"
  11 #include "prefix.h"
  12 #include "if.h"
  13 #include "sockunion.h"
  14 #include "log.h"
  15 #include "sockopt.h"
  16 #include "privs.h"
  17 #include "lib_errors.h"
  18 #include "lib/table.h"
  19
  20 #include "ospfd/ospfd.h"
  21 #include "ospfd/ospf_network.h"
  22 #include "ospfd/ospf_interface.h"
  23 #include "ospfd/ospf_asbr.h"
  24 #include "ospfd/ospf_lsa.h"
  25 #include "ospfd/ospf_lsdb.h"
  26 #include "ospfd/ospf_neighbor.h"
  27 #include "ospfd/ospf_packet.h"
  28 #include "ospfd/ospf_dump.h"
  29
  30 /* Join to the OSPF ALL SPF ROUTERS multicast group. */
  31 int ospf_if_add_allspfrouters(struct ospf *top, struct prefix *p,
  32                               ifindex_t ifindex)
  33 {
  34         int ret;
  35
  36         ret = setsockopt_ipv4_multicast(top->fd, IP_ADD_MEMBERSHIP,
  37                                         p->u.prefix4, htonl(OSPF_ALLSPFROUTERS),
  38                                         ifindex);
  39         if (ret < 0)
  40                 flog_err(
  41                         EC_LIB_SOCKET,
  42                         "can't setsockopt IP_ADD_MEMBERSHIP (fd %d, addr %pI4, ifindex %u, AllSPFRouters): %s; perhaps a kernel limit on # of multicast group memberships has been exceeded?",
  43                         top->fd, &p->u.prefix4, ifindex,
  44                         safe_strerror(errno));
  45         else {
  46                 if (IS_DEBUG_OSPF_EVENT)
  47                         zlog_debug(
  48                                 "interface %pI4 [%u] join AllSPFRouters Multicast group.",
  49                                 &p->u.prefix4, ifindex);
  50         }
  51
  52         return ret;
  53 }
  54
  55 int ospf_if_drop_allspfrouters(struct ospf *top, struct prefix *p,
  56                                ifindex_t ifindex)
  57 {
  58         int ret;
  59
  60         ret = setsockopt_ipv4_multicast(top->fd, IP_DROP_MEMBERSHIP,
  61                                         p->u.prefix4, htonl(OSPF_ALLSPFROUTERS),
  62                                         ifindex);
  63         if (ret < 0)
  64                 flog_err(EC_LIB_SOCKET,
  65                          "can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %pI4, ifindex %u, AllSPFRouters): %s",
  66                          top->fd, &p->u.prefix4, ifindex,
  67                          safe_strerror(errno));
  68         else {
  69                 if (IS_DEBUG_OSPF_EVENT)
  70                         zlog_debug(
  71                                 "interface %pI4 [%u] leave AllSPFRouters Multicast group.",
  72                                 &p->u.prefix4, ifindex);
  73         }
  74
  75         return ret;
  76 }
  77
  78 /* Join to the OSPF ALL Designated ROUTERS multicast group. */
  79 int ospf_if_add_alldrouters(struct ospf *top, struct prefix *p,
  80                             ifindex_t ifindex)
  81 {
  82         int ret;
  83
  84         ret = setsockopt_ipv4_multicast(top->fd, IP_ADD_MEMBERSHIP,
  85                                         p->u.prefix4, htonl(OSPF_ALLDROUTERS),
  86                                         ifindex);
  87         if (ret < 0)
  88                 flog_err(
  89                         EC_LIB_SOCKET,
  90                         "can't setsockopt IP_ADD_MEMBERSHIP (fd %d, addr %pI4, ifindex %u, AllDRouters): %s; perhaps a kernel limit on # of multicast group memberships has been exceeded?",
  91                         top->fd, &p->u.prefix4, ifindex,
  92                         safe_strerror(errno));
  93         else {
  94                 if (IS_DEBUG_OSPF_EVENT)
  95                         zlog_debug(
  96                                 "interface %pI4 [%u] join AllDRouters Multicast group.",
  97                                 &p->u.prefix4, ifindex);
  98         }
  99         return ret;
 100 }
 101
 102 int ospf_if_drop_alldrouters(struct ospf *top, struct prefix *p,
 103                              ifindex_t ifindex)
 104 {
 105         int ret;
 106
 107         ret = setsockopt_ipv4_multicast(top->fd, IP_DROP_MEMBERSHIP,
 108                                         p->u.prefix4, htonl(OSPF_ALLDROUTERS),
 109                                         ifindex);
 110         if (ret < 0)
 111                 flog_err(EC_LIB_SOCKET,
 112                          "can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %pI4, ifindex %u, AllDRouters): %s",
 113                          top->fd, &p->u.prefix4, ifindex,
 114                          safe_strerror(errno));
 115         else if (IS_DEBUG_OSPF_EVENT)
 116                 zlog_debug(
 117                         "interface %pI4 [%u] leave AllDRouters Multicast group.",
 118                         &p->u.prefix4, ifindex);
 119
 120         return ret;
 121 }
 122
 123 int ospf_if_ipmulticast(int fd, struct prefix *p, ifindex_t ifindex)
 124 {
 125         uint8_t val;
 126         int ret, len;
 127
 128         /* Prevent receiving self-origined multicast packets. */
 129         ret = setsockopt_ipv4_multicast_loop(fd, 0);
 130         if (ret < 0)
 131                 flog_err(EC_LIB_SOCKET,
 132                          "can't setsockopt IP_MULTICAST_LOOP(0) for fd %d: %s",
 133                          fd, safe_strerror(errno));
 134
 135         /* Explicitly set multicast ttl to 1 -- endo. */
 136         val = 1;
 137         len = sizeof(val);
 138         ret = setsockopt(fd, IPPROTO_IP, IP_MULTICAST_TTL, (void *)&val, len);
 139         if (ret < 0)
 140                 flog_err(EC_LIB_SOCKET,
 141                          "can't setsockopt IP_MULTICAST_TTL(1) for fd %d: %s",
 142                          fd, safe_strerror(errno));
 143 #ifndef GNU_LINUX
 144         /* For GNU LINUX ospf_write uses IP_PKTINFO, in_pktinfo to send
 145          * packet out of ifindex. Below would be used Non Linux system.
 146          */
 147         ret = setsockopt_ipv4_multicast_if(fd, p->u.prefix4, ifindex);
 148         if (ret < 0)
 149                 flog_err(EC_LIB_SOCKET,
 150                          "can't setsockopt IP_MULTICAST_IF(fd %d, addr %pI4, ifindex %u): %s",
 151                          fd, &p->u.prefix4, ifindex,
 152                          safe_strerror(errno));
 153 #endif
 154
 155         return ret;
 156 }
 157
 158 /*
 159  * Helper to open and set up a socket; returns the new fd on success,
 160  * -1 on error.
 161  */
 162 static int sock_init_common(vrf_id_t vrf_id, const char *name, int *pfd)
 163 {
 164         int ospf_sock;
 165         int ret, hincl = 1;
 166
 167         if (vrf_id == VRF_UNKNOWN) {
 168                 /* silently return since VRF is not ready */
 169                 return -1;
 170         }
 171
 172         frr_with_privs(&ospfd_privs) {
 173                 ospf_sock = vrf_socket(AF_INET, SOCK_RAW, IPPROTO_OSPFIGP,
 174                                        vrf_id, name);
 175                 if (ospf_sock < 0) {
 176                         flog_err(EC_LIB_SOCKET, "%s: socket: %s", __func__,
 177                                  safe_strerror(errno));
 178                         return -1;
 179                 }
 180
 181 #ifdef IP_HDRINCL
 182                 /* we will include IP header with packet */
 183                 ret = setsockopt(ospf_sock, IPPROTO_IP, IP_HDRINCL, &hincl,
 184                                  sizeof(hincl));
 185                 if (ret < 0) {
 186                         flog_err(EC_LIB_SOCKET,
 187                                  "Can't set IP_HDRINCL option for fd %d: %s",
 188                                  ospf_sock, safe_strerror(errno));
 189                         break;
 190                 }
 191 #elif defined(IPTOS_PREC_INTERNETCONTROL)
 192 #warning "IP_HDRINCL not available on this system"
 193 #warning "using IPTOS_PREC_INTERNETCONTROL"
 194                 ret = setsockopt_ipv4_tos(ospf_sock,
 195                                           IPTOS_PREC_INTERNETCONTROL);
 196                 if (ret < 0) {
 197                         flog_err(EC_LIB_SOCKET,
 198                                  "can't set sockopt IP_TOS %d to socket %d: %s",
 199                                  tos, ospf_sock, safe_strerror(errno));
 200                         break;
 201                 }
 202 #else /* !IPTOS_PREC_INTERNETCONTROL */
 203 #warning "IP_HDRINCL not available, nor is IPTOS_PREC_INTERNETCONTROL"
 204                 flog_err(EC_LIB_UNAVAILABLE, "IP_HDRINCL option not available");
 205 #endif /* IP_HDRINCL */
 206
 207                 ret = setsockopt_ifindex(AF_INET, ospf_sock, 1);
 208
 209                 if (ret < 0)
 210                         flog_err(EC_LIB_SOCKET,
 211                                  "Can't set pktinfo option for fd %d",
 212                                  ospf_sock);
 213         }
 214
 215         *pfd = ospf_sock;
 216
 217         return ret;
 218 }
 219
 220 /*
 221  * Update a socket bufsize(s), based on its ospf instance
 222  */
 223 void ospf_sock_bufsize_update(const struct ospf *ospf, int sock,
 224                               enum ospf_sock_type_e type)
 225 {
 226         int bufsize;
 227
 228         if (type == OSPF_SOCK_BOTH || type == OSPF_SOCK_RECV) {
 229                 bufsize = ospf->recv_sock_bufsize;
 230                 setsockopt_so_recvbuf(sock, bufsize);
 231         }
 232
 233         if (type == OSPF_SOCK_BOTH || type == OSPF_SOCK_SEND) {
 234                 bufsize = ospf->send_sock_bufsize;
 235                 setsockopt_so_sendbuf(sock, bufsize);
 236         }
 237 }
 238
 239 int ospf_sock_init(struct ospf *ospf)
 240 {
 241         int ret;
 242
 243         /* silently ignore. already done */
 244         if (ospf->fd > 0)
 245                 return -1;
 246
 247         ret = sock_init_common(ospf->vrf_id, ospf->name, &(ospf->fd));
 248
 249         if (ret >= 0) /* Update socket buffer sizes */
 250                 ospf_sock_bufsize_update(ospf, ospf->fd, OSPF_SOCK_BOTH);
 251
 252         return ret;
 253 }
 254
 255 /*
 256  * Open per-interface write socket
 257  */
 258 int ospf_ifp_sock_init(struct interface *ifp)
 259 {
 260         struct ospf_if_info *oii;
 261         struct ospf_interface *oi;
 262         struct ospf *ospf;
 263         struct route_node *rn;
 264         int ret;
 265
 266         oii = IF_OSPF_IF_INFO(ifp);
 267         if (oii == NULL)
 268                 return -1;
 269
 270         if (oii->oii_fd > 0)
 271                 return 0;
 272
 273         rn = route_top(IF_OIFS(ifp));
 274         if (rn && rn->info) {
 275                 oi = rn->info;
 276                 ospf = oi->ospf;
 277         } else
 278                 return -1;
 279
 280         ret = sock_init_common(ifp->vrf->vrf_id, ifp->name, &oii->oii_fd);
 281
 282         if (ret >= 0) /* Update socket buffer sizes */
 283                 ospf_sock_bufsize_update(ospf, oii->oii_fd, OSPF_SOCK_BOTH);
 284
 285         if (IS_DEBUG_OSPF_EVENT)
 286                 zlog_debug("%s: ifp %s, oii %p, fd %d", __func__, ifp->name,
 287                            oii, oii->oii_fd);
 288
 289         return ret;
 290 }
 291
 292 /*
 293  * Close per-interface write socket
 294  */
 295 int ospf_ifp_sock_close(struct interface *ifp)
 296 {
 297         struct ospf_if_info *oii;
 298
 299         oii = IF_OSPF_IF_INFO(ifp);
 300         if (oii == NULL)
 301                 return 0;
 302
 303         if (oii->oii_fd > 0) {
 304                 if (IS_DEBUG_OSPF_EVENT)
 305                         zlog_debug("%s: ifp %s, oii %p, fd %d", __func__,
 306                                    ifp->name, oii, oii->oii_fd);
 307
 308                 close(oii->oii_fd);
 309                 oii->oii_fd = -1;
 310         }
 311
 312         return 0;
 313 }