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 int               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 int               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 int
 105 control_accept(struct thread *thread)
 106 {
 107         int                      connfd;
 108         socklen_t                len;
 109         struct sockaddr_un       s_un;
 110         struct ctl_conn         *c;
 111
 112         len = sizeof(s_un);
 113         if ((connfd = accept(THREAD_FD(thread), (struct sockaddr *)&s_un,
 114             &len)) == -1) {
 115                 /*
 116                  * Pause accept if we are out of file descriptors, or
 117                  * libevent will haunt us here too.
 118                  */
 119                 if (errno == ENFILE || errno == EMFILE)
 120                         accept_pause();
 121                 else if (errno != EWOULDBLOCK && errno != EINTR &&
 122                     errno != ECONNABORTED)
 123                         log_warn("%s: accept", __func__);
 124                 return (0);
 125         }
 126         sock_set_nonblock(connfd);
 127
 128         if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) {
 129                 log_warn(__func__);
 130                 close(connfd);
 131                 return (0);
 132         }
 133
 134         imsg_init(&c->iev.ibuf, connfd);
 135         c->iev.handler_read = control_dispatch_imsg;
 136         c->iev.ev_read = NULL;
 137         thread_add_read(master, c->iev.handler_read, &c->iev, c->iev.ibuf.fd,
 138                         &c->iev.ev_read);
 139         c->iev.handler_write = ldp_write_handler;
 140         c->iev.ev_write = NULL;
 141
 142         TAILQ_INSERT_TAIL(&ctl_conns, c, entry);
 143
 144         return (0);
 145 }
 146
 147 static struct ctl_conn *
 148 control_connbyfd(int fd)
 149 {
 150         struct ctl_conn *c;
 151
 152         TAILQ_FOREACH(c, &ctl_conns, entry) {
 153                 if (c->iev.ibuf.fd == fd)
 154                         break;
 155         }
 156
 157         return (c);
 158 }
 159
 160 static struct ctl_conn *
 161 control_connbypid(pid_t pid)
 162 {
 163         struct ctl_conn *c;
 164
 165         TAILQ_FOREACH(c, &ctl_conns, entry) {
 166                 if (c->iev.ibuf.pid == pid)
 167                         break;
 168         }
 169
 170         return (c);
 171 }
 172
 173 static void
 174 control_close(int fd)
 175 {
 176         struct ctl_conn *c;
 177
 178         if ((c = control_connbyfd(fd)) == NULL) {
 179                 log_warnx("%s: fd %d: not found", __func__, fd);
 180                 return;
 181         }
 182
 183         msgbuf_clear(&c->iev.ibuf.w);
 184         TAILQ_REMOVE(&ctl_conns, c, entry);
 185
 186         THREAD_READ_OFF(c->iev.ev_read);
 187         THREAD_WRITE_OFF(c->iev.ev_write);
 188         close(c->iev.ibuf.fd);
 189         accept_unpause();
 190         free(c);
 191 }
 192
 193 /* ARGSUSED */
 194 static int
 195 control_dispatch_imsg(struct thread *thread)
 196 {
 197         int              fd = THREAD_FD(thread);
 198         struct ctl_conn *c;
 199         struct imsg      imsg;
 200         ssize_t          n;
 201         unsigned int     ifidx;
 202
 203         if ((c = control_connbyfd(fd)) == NULL) {
 204                 log_warnx("%s: fd %d: not found", __func__, fd);
 205                 return (0);
 206         }
 207
 208         c->iev.ev_read = NULL;
 209
 210         if (((n = imsg_read(&c->iev.ibuf)) == -1 && errno != EAGAIN) ||
 211             n == 0) {
 212                 control_close(fd);
 213                 return (0);
 214         }
 215
 216         for (;;) {
 217                 if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) {
 218                         control_close(fd);
 219                         return (0);
 220                 }
 221
 222                 if (n == 0)
 223                         break;
 224
 225                 switch (imsg.hdr.type) {
 226                 case IMSG_CTL_FIB_COUPLE:
 227                 case IMSG_CTL_FIB_DECOUPLE:
 228                 case IMSG_CTL_RELOAD:
 229                 case IMSG_CTL_KROUTE:
 230                 case IMSG_CTL_KROUTE_ADDR:
 231                 case IMSG_CTL_IFINFO:
 232                         /* ignore */
 233                         break;
 234                 case IMSG_CTL_SHOW_INTERFACE:
 235                         if (imsg.hdr.len == IMSG_HEADER_SIZE +
 236                             sizeof(ifidx)) {
 237                                 memcpy(&ifidx, imsg.data, sizeof(ifidx));
 238                                 ldpe_iface_ctl(c, ifidx);
 239                                 imsg_compose_event(&c->iev, IMSG_CTL_END, 0,
 240                                     0, -1, NULL, 0);
 241                         }
 242                         break;
 243                 case IMSG_CTL_SHOW_DISCOVERY:
 244                         ldpe_adj_ctl(c);
 245                         break;
 246                 case IMSG_CTL_SHOW_DISCOVERY_DTL:
 247                         ldpe_adj_detail_ctl(c);
 248                         break;
 249                 case IMSG_CTL_SHOW_LIB:
 250                 case IMSG_CTL_SHOW_L2VPN_PW:
 251                 case IMSG_CTL_SHOW_L2VPN_BINDING:
 252                         c->iev.ibuf.pid = imsg.hdr.pid;
 253                         ldpe_imsg_compose_lde(imsg.hdr.type, 0, imsg.hdr.pid,
 254                             imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
 255                         break;
 256                 case IMSG_CTL_SHOW_NBR:
 257                         ldpe_nbr_ctl(c);
 258                         break;
 259                 case IMSG_CTL_CLEAR_NBR:
 260                         if (imsg.hdr.len != IMSG_HEADER_SIZE +
 261                             sizeof(struct ctl_nbr))
 262                                 break;
 263
 264                         nbr_clear_ctl(imsg.data);
 265                         break;
 266                 case IMSG_CTL_LOG_VERBOSE:
 267                         /* ignore */
 268                         break;
 269                 default:
 270                         log_debug("%s: error handling imsg %d", __func__,
 271                             imsg.hdr.type);
 272                         break;
 273                 }
 274                 imsg_free(&imsg);
 275         }
 276
 277         imsg_event_add(&c->iev);
 278
 279         return (0);
 280 }
 281
 282 int
 283 control_imsg_relay(struct imsg *imsg)
 284 {
 285         struct ctl_conn *c;
 286
 287         if ((c = control_connbypid(imsg->hdr.pid)) == NULL)
 288                 return (0);
 289
 290         return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid,
 291             -1, imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE));
 292 }