ldpd/control.c

   1 /*      $OpenBSD$ */
   2
   3 /*
   4  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
   5  *
   6  * Permission to use, copy, modify, and distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18
  19 #include <zebra.h>
  20 #include <sys/un.h>
  21
  22 #include "ldpd.h"
  23 #include "ldpe.h"
  24 #include "log.h"
  25 #include "control.h"
  26
  27 #define CONTROL_BACKLOG 5
  28
  29 static void control_accept(struct thread *);
  30 static struct ctl_conn  *control_connbyfd(int);
  31 static struct ctl_conn  *control_connbypid(pid_t);
  32 static void              control_close(int);
  33 static void control_dispatch_imsg(struct thread *);
  34
  35 struct ctl_conns         ctl_conns;
  36
  37 static int               control_fd;
  38
  39 int
  40 control_init(char *path)
  41 {
  42         struct sockaddr_un       s_un;
  43         int                      fd;
  44         mode_t                   old_umask;
  45
  46         if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) {
  47                 log_warn("%s: socket", __func__);
  48                 return (-1);
  49         }
  50         sock_set_nonblock(fd);
  51
  52         memset(&s_un, 0, sizeof(s_un));
  53         s_un.sun_family = AF_UNIX;
  54         strlcpy(s_un.sun_path, path, sizeof(s_un.sun_path));
  55
  56         if (unlink(path) == -1)
  57                 if (errno != ENOENT) {
  58                         log_warn("%s: unlink %s", __func__, path);
  59                         close(fd);
  60                         return (-1);
  61                 }
  62
  63         old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH);
  64         if (bind(fd, (struct sockaddr *)&s_un, sizeof(s_un)) == -1) {
  65                 log_warn("%s: bind: %s", __func__, path);
  66                 close(fd);
  67                 umask(old_umask);
  68                 return (-1);
  69         }
  70         umask(old_umask);
  71
  72         if (chmod(path, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP) == -1) {
  73                 log_warn("%s: chmod", __func__);
  74                 close(fd);
  75                 (void)unlink(path);
  76                 return (-1);
  77         }
  78
  79         control_fd = fd;
  80
  81         return (0);
  82 }
  83
  84 int
  85 control_listen(void)
  86 {
  87         if (listen(control_fd, CONTROL_BACKLOG) == -1) {
  88                 log_warn("%s: listen", __func__);
  89                 return (-1);
  90         }
  91
  92         return (accept_add(control_fd, control_accept, NULL));
  93 }
  94
  95 void
  96 control_cleanup(char *path)
  97 {
  98         accept_del(control_fd);
  99         close(control_fd);
 100         unlink(path);
 101 }
 102
 103 /* ARGSUSED */
 104 static void control_accept(struct thread *thread)
 105 {
 106         int                      connfd;
 107         socklen_t                len;
 108         struct sockaddr_un       s_un;
 109         struct ctl_conn         *c;
 110
 111         len = sizeof(s_un);
 112         if ((connfd = accept(THREAD_FD(thread), (struct sockaddr *)&s_un,
 113             &len)) == -1) {
 114                 /*
 115                  * Pause accept if we are out of file descriptors, or
 116                  * libevent will haunt us here too.
 117                  */
 118                 if (errno == ENFILE || errno == EMFILE)
 119                         accept_pause();
 120                 else if (errno != EWOULDBLOCK && errno != EINTR &&
 121                     errno != ECONNABORTED)
 122                         log_warn("%s: accept", __func__);
 123                 return;
 124         }
 125         sock_set_nonblock(connfd);
 126
 127         if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) {
 128                 log_warn(__func__);
 129                 close(connfd);
 130                 return;
 131         }
 132
 133         imsg_init(&c->iev.ibuf, connfd);
 134         c->iev.handler_read = control_dispatch_imsg;
 135         c->iev.ev_read = NULL;
 136         thread_add_read(master, c->iev.handler_read, &c->iev, c->iev.ibuf.fd,
 137                         &c->iev.ev_read);
 138         c->iev.handler_write = ldp_write_handler;
 139         c->iev.ev_write = NULL;
 140
 141         TAILQ_INSERT_TAIL(&ctl_conns, c, entry);
 142 }
 143
 144 static struct ctl_conn *
 145 control_connbyfd(int fd)
 146 {
 147         struct ctl_conn *c;
 148
 149         TAILQ_FOREACH(c, &ctl_conns, entry) {
 150                 if (c->iev.ibuf.fd == fd)
 151                         break;
 152         }
 153
 154         return (c);
 155 }
 156
 157 static struct ctl_conn *
 158 control_connbypid(pid_t pid)
 159 {
 160         struct ctl_conn *c;
 161
 162         TAILQ_FOREACH(c, &ctl_conns, entry) {
 163                 if (c->iev.ibuf.pid == pid)
 164                         break;
 165         }
 166
 167         return (c);
 168 }
 169
 170 static void
 171 control_close(int fd)
 172 {
 173         struct ctl_conn *c;
 174
 175         if ((c = control_connbyfd(fd)) == NULL) {
 176                 log_warnx("%s: fd %d: not found", __func__, fd);
 177                 return;
 178         }
 179
 180         msgbuf_clear(&c->iev.ibuf.w);
 181         TAILQ_REMOVE(&ctl_conns, c, entry);
 182
 183         THREAD_OFF(c->iev.ev_read);
 184         THREAD_OFF(c->iev.ev_write);
 185         close(c->iev.ibuf.fd);
 186         accept_unpause();
 187         free(c);
 188 }
 189
 190 /* ARGSUSED */
 191 static void control_dispatch_imsg(struct thread *thread)
 192 {
 193         int              fd = THREAD_FD(thread);
 194         struct ctl_conn *c;
 195         struct imsg      imsg;
 196         ssize_t          n;
 197         unsigned int     ifidx;
 198
 199         if ((c = control_connbyfd(fd)) == NULL) {
 200                 log_warnx("%s: fd %d: not found", __func__, fd);
 201                 return;
 202         }
 203
 204         c->iev.ev_read = NULL;
 205
 206         if (((n = imsg_read(&c->iev.ibuf)) == -1 && errno != EAGAIN) ||
 207             n == 0) {
 208                 control_close(fd);
 209                 return;
 210         }
 211
 212         for (;;) {
 213                 if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) {
 214                         control_close(fd);
 215                         return;
 216                 }
 217
 218                 if (n == 0)
 219                         break;
 220
 221                 switch (imsg.hdr.type) {
 222                 case IMSG_CTL_FIB_COUPLE:
 223                 case IMSG_CTL_FIB_DECOUPLE:
 224                 case IMSG_CTL_RELOAD:
 225                 case IMSG_CTL_KROUTE:
 226                 case IMSG_CTL_KROUTE_ADDR:
 227                 case IMSG_CTL_IFINFO:
 228                         /* ignore */
 229                         break;
 230                 case IMSG_CTL_SHOW_INTERFACE:
 231                         if (imsg.hdr.len == IMSG_HEADER_SIZE +
 232                             sizeof(ifidx)) {
 233                                 memcpy(&ifidx, imsg.data, sizeof(ifidx));
 234                                 ldpe_iface_ctl(c, ifidx);
 235                                 imsg_compose_event(&c->iev, IMSG_CTL_END, 0,
 236                                     0, -1, NULL, 0);
 237                         }
 238                         break;
 239                 case IMSG_CTL_SHOW_DISCOVERY:
 240                         ldpe_adj_ctl(c);
 241                         break;
 242                 case IMSG_CTL_SHOW_DISCOVERY_DTL:
 243                         ldpe_adj_detail_ctl(c);
 244                         break;
 245                 case IMSG_CTL_SHOW_LIB:
 246                 case IMSG_CTL_SHOW_L2VPN_PW:
 247                 case IMSG_CTL_SHOW_L2VPN_BINDING:
 248                         c->iev.ibuf.pid = imsg.hdr.pid;
 249                         ldpe_imsg_compose_lde(imsg.hdr.type, 0, imsg.hdr.pid,
 250                             imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
 251                         break;
 252                 case IMSG_CTL_SHOW_NBR:
 253                         ldpe_nbr_ctl(c);
 254                         break;
 255                 case IMSG_CTL_CLEAR_NBR:
 256                         if (imsg.hdr.len != IMSG_HEADER_SIZE +
 257                             sizeof(struct ctl_nbr))
 258                                 break;
 259
 260                         nbr_clear_ctl(imsg.data);
 261                         break;
 262                 case IMSG_CTL_SHOW_LDP_SYNC:
 263                         ldpe_ldp_sync_ctl(c);
 264                         break;
 265                 case IMSG_CTL_LOG_VERBOSE:
 266                         /* ignore */
 267                         break;
 268                 default:
 269                         log_debug("%s: error handling imsg %d", __func__,
 270                             imsg.hdr.type);
 271                         break;
 272                 }
 273                 imsg_free(&imsg);
 274         }
 275
 276         imsg_event_add(&c->iev);
 277 }
 278
 279 int
 280 control_imsg_relay(struct imsg *imsg)
 281 {
 282         struct ctl_conn *c;
 283
 284         if ((c = control_connbypid(imsg->hdr.pid)) == NULL)
 285                 return (0);
 286
 287         return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid,
 288             -1, imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE));
 289 }