ldpd/control.c

   1 // SPDX-License-Identifier: ISC
   2 /*      $OpenBSD$ */
   3
   4 /*
   5  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
   6  */
   7
   8 #include <zebra.h>
   9 #include <sys/un.h>
  10
  11 #include "ldpd.h"
  12 #include "ldpe.h"
  13 #include "log.h"
  14 #include "control.h"
  15
  16 #define CONTROL_BACKLOG 5
  17
  18 static void control_accept(struct thread *);
  19 static struct ctl_conn  *control_connbyfd(int);
  20 static struct ctl_conn  *control_connbypid(pid_t);
  21 static void              control_close(int);
  22 static void control_dispatch_imsg(struct thread *);
  23
  24 struct ctl_conns         ctl_conns;
  25
  26 static int               control_fd;
  27
  28 int
  29 control_init(char *path)
  30 {
  31         struct sockaddr_un       s_un;
  32         int                      fd;
  33         mode_t                   old_umask;
  34
  35         if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) {
  36                 log_warn("%s: socket", __func__);
  37                 return (-1);
  38         }
  39         sock_set_nonblock(fd);
  40
  41         memset(&s_un, 0, sizeof(s_un));
  42         s_un.sun_family = AF_UNIX;
  43         strlcpy(s_un.sun_path, path, sizeof(s_un.sun_path));
  44
  45         if (unlink(path) == -1)
  46                 if (errno != ENOENT) {
  47                         log_warn("%s: unlink %s", __func__, path);
  48                         close(fd);
  49                         return (-1);
  50                 }
  51
  52         old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH);
  53         if (bind(fd, (struct sockaddr *)&s_un, sizeof(s_un)) == -1) {
  54                 log_warn("%s: bind: %s", __func__, path);
  55                 close(fd);
  56                 umask(old_umask);
  57                 return (-1);
  58         }
  59         umask(old_umask);
  60
  61         if (chmod(path, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP) == -1) {
  62                 log_warn("%s: chmod", __func__);
  63                 close(fd);
  64                 (void)unlink(path);
  65                 return (-1);
  66         }
  67
  68         control_fd = fd;
  69
  70         return (0);
  71 }
  72
  73 int
  74 control_listen(void)
  75 {
  76         if (listen(control_fd, CONTROL_BACKLOG) == -1) {
  77                 log_warn("%s: listen", __func__);
  78                 return (-1);
  79         }
  80
  81         return (accept_add(control_fd, control_accept, NULL));
  82 }
  83
  84 void
  85 control_cleanup(char *path)
  86 {
  87         accept_del(control_fd);
  88         close(control_fd);
  89         unlink(path);
  90 }
  91
  92 /* ARGSUSED */
  93 static void control_accept(struct thread *thread)
  94 {
  95         int                      connfd;
  96         socklen_t                len;
  97         struct sockaddr_un       s_un;
  98         struct ctl_conn         *c;
  99
 100         len = sizeof(s_un);
 101         if ((connfd = accept(THREAD_FD(thread), (struct sockaddr *)&s_un,
 102             &len)) == -1) {
 103                 /*
 104                  * Pause accept if we are out of file descriptors, or
 105                  * libevent will haunt us here too.
 106                  */
 107                 if (errno == ENFILE || errno == EMFILE)
 108                         accept_pause();
 109                 else if (errno != EWOULDBLOCK && errno != EINTR &&
 110                     errno != ECONNABORTED)
 111                         log_warn("%s: accept", __func__);
 112                 return;
 113         }
 114         sock_set_nonblock(connfd);
 115
 116         if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) {
 117                 log_warn(__func__);
 118                 close(connfd);
 119                 return;
 120         }
 121
 122         imsg_init(&c->iev.ibuf, connfd);
 123         c->iev.handler_read = control_dispatch_imsg;
 124         c->iev.ev_read = NULL;
 125         thread_add_read(master, c->iev.handler_read, &c->iev, c->iev.ibuf.fd,
 126                         &c->iev.ev_read);
 127         c->iev.handler_write = ldp_write_handler;
 128         c->iev.ev_write = NULL;
 129
 130         TAILQ_INSERT_TAIL(&ctl_conns, c, entry);
 131 }
 132
 133 static struct ctl_conn *
 134 control_connbyfd(int fd)
 135 {
 136         struct ctl_conn *c;
 137
 138         TAILQ_FOREACH(c, &ctl_conns, entry) {
 139                 if (c->iev.ibuf.fd == fd)
 140                         break;
 141         }
 142
 143         return (c);
 144 }
 145
 146 static struct ctl_conn *
 147 control_connbypid(pid_t pid)
 148 {
 149         struct ctl_conn *c;
 150
 151         TAILQ_FOREACH(c, &ctl_conns, entry) {
 152                 if (c->iev.ibuf.pid == pid)
 153                         break;
 154         }
 155
 156         return (c);
 157 }
 158
 159 static void
 160 control_close(int fd)
 161 {
 162         struct ctl_conn *c;
 163
 164         if ((c = control_connbyfd(fd)) == NULL) {
 165                 log_warnx("%s: fd %d: not found", __func__, fd);
 166                 return;
 167         }
 168
 169         msgbuf_clear(&c->iev.ibuf.w);
 170         TAILQ_REMOVE(&ctl_conns, c, entry);
 171
 172         THREAD_OFF(c->iev.ev_read);
 173         THREAD_OFF(c->iev.ev_write);
 174         close(c->iev.ibuf.fd);
 175         accept_unpause();
 176         free(c);
 177 }
 178
 179 /* ARGSUSED */
 180 static void control_dispatch_imsg(struct thread *thread)
 181 {
 182         int              fd = THREAD_FD(thread);
 183         struct ctl_conn *c;
 184         struct imsg      imsg;
 185         ssize_t          n;
 186         unsigned int     ifidx;
 187
 188         if ((c = control_connbyfd(fd)) == NULL) {
 189                 log_warnx("%s: fd %d: not found", __func__, fd);
 190                 return;
 191         }
 192
 193         c->iev.ev_read = NULL;
 194
 195         if (((n = imsg_read(&c->iev.ibuf)) == -1 && errno != EAGAIN) ||
 196             n == 0) {
 197                 control_close(fd);
 198                 return;
 199         }
 200
 201         for (;;) {
 202                 if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) {
 203                         control_close(fd);
 204                         return;
 205                 }
 206
 207                 if (n == 0)
 208                         break;
 209
 210                 switch (imsg.hdr.type) {
 211                 case IMSG_CTL_FIB_COUPLE:
 212                 case IMSG_CTL_FIB_DECOUPLE:
 213                 case IMSG_CTL_RELOAD:
 214                 case IMSG_CTL_KROUTE:
 215                 case IMSG_CTL_KROUTE_ADDR:
 216                 case IMSG_CTL_IFINFO:
 217                         /* ignore */
 218                         break;
 219                 case IMSG_CTL_SHOW_INTERFACE:
 220                         if (imsg.hdr.len == IMSG_HEADER_SIZE +
 221                             sizeof(ifidx)) {
 222                                 memcpy(&ifidx, imsg.data, sizeof(ifidx));
 223                                 ldpe_iface_ctl(c, ifidx);
 224                                 imsg_compose_event(&c->iev, IMSG_CTL_END, 0,
 225                                     0, -1, NULL, 0);
 226                         }
 227                         break;
 228                 case IMSG_CTL_SHOW_DISCOVERY:
 229                         ldpe_adj_ctl(c);
 230                         break;
 231                 case IMSG_CTL_SHOW_DISCOVERY_DTL:
 232                         ldpe_adj_detail_ctl(c);
 233                         break;
 234                 case IMSG_CTL_SHOW_LIB:
 235                 case IMSG_CTL_SHOW_L2VPN_PW:
 236                 case IMSG_CTL_SHOW_L2VPN_BINDING:
 237                         c->iev.ibuf.pid = imsg.hdr.pid;
 238                         ldpe_imsg_compose_lde(imsg.hdr.type, 0, imsg.hdr.pid,
 239                             imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
 240                         break;
 241                 case IMSG_CTL_SHOW_NBR:
 242                         ldpe_nbr_ctl(c);
 243                         break;
 244                 case IMSG_CTL_CLEAR_NBR:
 245                         if (imsg.hdr.len != IMSG_HEADER_SIZE +
 246                             sizeof(struct ctl_nbr))
 247                                 break;
 248
 249                         nbr_clear_ctl(imsg.data);
 250                         break;
 251                 case IMSG_CTL_SHOW_LDP_SYNC:
 252                         ldpe_ldp_sync_ctl(c);
 253                         break;
 254                 case IMSG_CTL_LOG_VERBOSE:
 255                         /* ignore */
 256                         break;
 257                 default:
 258                         log_debug("%s: error handling imsg %d", __func__,
 259                             imsg.hdr.type);
 260                         break;
 261                 }
 262                 imsg_free(&imsg);
 263         }
 264
 265         imsg_event_add(&c->iev);
 266 }
 267
 268 int
 269 control_imsg_relay(struct imsg *imsg)
 270 {
 271         struct ctl_conn *c;
 272
 273         if ((c = control_connbypid(imsg->hdr.pid)) == NULL)
 274                 return (0);
 275
 276         return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid,
 277             -1, imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE));
 278 }