service/instance.c

   1 /*
   2  * Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
   3  * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU Lesser General Public License version 2.1
   7  * as published by the Free Software Foundation
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <sys/resource.h>
  16 #include <sys/types.h>
  17 #include <sys/socket.h>
  18 #include <net/if.h>
  19 #include <unistd.h>
  20 #include <stdint.h>
  21 #include <fcntl.h>
  22
  23 #include <libubox/md5.h>
  24
  25 #include "../procd.h"
  26
  27 #include "service.h"
  28 #include "instance.h"
  29
  30
  31 enum {
  32         INSTANCE_ATTR_COMMAND,
  33         INSTANCE_ATTR_ENV,
  34         INSTANCE_ATTR_DATA,
  35         INSTANCE_ATTR_NETDEV,
  36         INSTANCE_ATTR_FILE,
  37         INSTANCE_ATTR_TRIGGER,
  38         INSTANCE_ATTR_RESPAWN,
  39         INSTANCE_ATTR_NICE,
  40         INSTANCE_ATTR_LIMITS,
  41         INSTANCE_ATTR_WATCH,
  42         __INSTANCE_ATTR_MAX
  43 };
  44
  45 static const struct blobmsg_policy instance_attr[__INSTANCE_ATTR_MAX] = {
  46         [INSTANCE_ATTR_COMMAND] = { "command", BLOBMSG_TYPE_ARRAY },
  47         [INSTANCE_ATTR_ENV] = { "env", BLOBMSG_TYPE_TABLE },
  48         [INSTANCE_ATTR_DATA] = { "data", BLOBMSG_TYPE_TABLE },
  49         [INSTANCE_ATTR_NETDEV] = { "netdev", BLOBMSG_TYPE_ARRAY },
  50         [INSTANCE_ATTR_FILE] = { "file", BLOBMSG_TYPE_ARRAY },
  51         [INSTANCE_ATTR_TRIGGER] = { "triggers", BLOBMSG_TYPE_ARRAY },
  52         [INSTANCE_ATTR_RESPAWN] = { "respawn", BLOBMSG_TYPE_ARRAY },
  53         [INSTANCE_ATTR_NICE] = { "nice", BLOBMSG_TYPE_INT32 },
  54         [INSTANCE_ATTR_LIMITS] = { "limits", BLOBMSG_TYPE_TABLE },
  55         [INSTANCE_ATTR_WATCH] = { "watch", BLOBMSG_TYPE_ARRAY },
  56 };
  57
  58 struct instance_netdev {
  59         struct blobmsg_list_node node;
  60         int ifindex;
  61 };
  62
  63 struct instance_file {
  64         struct blobmsg_list_node node;
  65         uint32_t md5[4];
  66 };
  67
  68 struct rlimit_name {
  69         const char *name;
  70         int resource;
  71 };
  72
  73 static const struct rlimit_name rlimit_names[] = {
  74         { "as", RLIMIT_AS },
  75         { "core", RLIMIT_CORE },
  76         { "cpu", RLIMIT_CPU },
  77         { "data", RLIMIT_DATA },
  78         { "fsize", RLIMIT_FSIZE },
  79         { "memlock", RLIMIT_MEMLOCK },
  80         { "msgqueue", RLIMIT_MSGQUEUE },
  81         { "nice", RLIMIT_NICE },
  82         { "nofile", RLIMIT_NOFILE },
  83         { "nproc", RLIMIT_NPROC },
  84         { "rss", RLIMIT_RSS },
  85         { "rtprio", RLIMIT_RTPRIO },
  86         { "sigpending", RLIMIT_SIGPENDING },
  87         { "stack", RLIMIT_STACK },
  88         { NULL, 0 }
  89 };
  90
  91 static void
  92 instance_limits(const char *limit, const char *value)
  93 {
  94         int i;
  95         struct rlimit rlim;
  96         unsigned long cur, max;
  97
  98         for (i = 0; rlimit_names[i].name != NULL; i++) {
  99                 if (strcmp(rlimit_names[i].name, limit))
 100                         continue;
 101                 if (!strcmp(value, "unlimited")) {
 102                         rlim.rlim_cur = RLIM_INFINITY;
 103                         rlim.rlim_max = RLIM_INFINITY;
 104                 } else {
 105                         if (getrlimit(rlimit_names[i].resource, &rlim))
 106                                 return;
 107
 108                         cur = rlim.rlim_cur;
 109                         max = rlim.rlim_max;
 110
 111                         if (sscanf(value, "%lu %lu", &cur, &max) < 1)
 112                                 return;
 113
 114                         rlim.rlim_cur = cur;
 115                         rlim.rlim_max = max;
 116                 }
 117
 118                 setrlimit(rlimit_names[i].resource, &rlim);
 119                 return;
 120         }
 121 }
 122
 123 static void
 124 instance_run(struct service_instance *in)
 125 {
 126         struct blobmsg_list_node *var;
 127         struct blob_attr *cur;
 128         char **argv;
 129         int argc = 1; /* NULL terminated */
 130         int rem, fd;
 131
 132         if (in->nice)
 133                 setpriority(PRIO_PROCESS, 0, in->nice);
 134
 135         blobmsg_for_each_attr(cur, in->command, rem)
 136                 argc++;
 137
 138         blobmsg_list_for_each(&in->env, var)
 139                 setenv(blobmsg_name(var->data), blobmsg_data(var->data), 1);
 140
 141         blobmsg_list_for_each(&in->limits, var)
 142                 instance_limits(blobmsg_name(var->data), blobmsg_data(var->data));
 143
 144         argv = alloca(sizeof(char *) * argc);
 145         argc = 0;
 146
 147         blobmsg_for_each_attr(cur, in->command, rem)
 148                 argv[argc++] = blobmsg_data(cur);
 149
 150         argv[argc] = NULL;
 151         fd = open("/dev/null", O_RDWR);
 152         if (fd > -1) {
 153                 dup2(fd, STDIN_FILENO);
 154                 dup2(fd, STDOUT_FILENO);
 155                 dup2(fd, STDERR_FILENO);
 156                 if (fd > STDERR_FILENO)
 157                         close(fd);
 158         }
 159         execvp(argv[0], argv);
 160         exit(127);
 161 }
 162
 163 void
 164 instance_start(struct service_instance *in)
 165 {
 166         int pid;
 167
 168         if (in->proc.pending)
 169                 return;
 170
 171         in->restart = false;
 172         in->halt = !in->respawn;
 173
 174         if (!in->valid)
 175                 return;
 176
 177         pid = fork();
 178         if (pid < 0)
 179                 return;
 180
 181         if (!pid) {
 182                 uloop_done();
 183                 instance_run(in);
 184                 return;
 185         }
 186
 187         DEBUG(2, "Started instance %s::%s\n", in->srv->name, in->name);
 188         in->proc.pid = pid;
 189         clock_gettime(CLOCK_MONOTONIC, &in->start);
 190         uloop_process_add(&in->proc);
 191         service_event("instance.start", in->srv->name, in->name);
 192 }
 193
 194 static void
 195 instance_timeout(struct uloop_timeout *t)
 196 {
 197         struct service_instance *in;
 198
 199         in = container_of(t, struct service_instance, timeout);
 200
 201         if (!in->halt && (in->restart || in->respawn))
 202                 instance_start(in);
 203 }
 204
 205 static void
 206 instance_exit(struct uloop_process *p, int ret)
 207 {
 208         struct service_instance *in;
 209         struct timespec tp;
 210         long runtime;
 211
 212         in = container_of(p, struct service_instance, proc);
 213
 214         clock_gettime(CLOCK_MONOTONIC, &tp);
 215         runtime = tp.tv_sec - in->start.tv_sec;
 216
 217         DEBUG(2, "Instance %s::%s exit with error code %d after %ld seconds\n", in->srv->name, in->name, ret, runtime);
 218         if (upgrade_running)
 219                 return;
 220
 221         uloop_timeout_cancel(&in->timeout);
 222         if (in->halt) {
 223                 /* no action */
 224         } else if (in->restart) {
 225                 instance_start(in);
 226         } else if (in->respawn) {
 227                 if (runtime < in->respawn_threshold)
 228                         in->respawn_count++;
 229                 else
 230                         in->respawn_count = 0;
 231                 if (in->respawn_count > in->respawn_retry && in->respawn_retry > 0 ) {
 232                         LOG("Instance %s::%s s in a crash loop %d crashes, %ld seconds since last crash\n",
 233                                                                 in->srv->name, in->name, in->respawn_count, runtime);
 234                         in->restart = in->respawn = 0;
 235                         in->halt = 1;
 236                 } else {
 237                         uloop_timeout_set(&in->timeout, in->respawn_timeout * 1000);
 238                 }
 239         }
 240         service_event("instance.stop", in->srv->name, in->name);
 241 }
 242
 243 void
 244 instance_stop(struct service_instance *in)
 245 {
 246         if (!in->proc.pending)
 247                 return;
 248         in->halt = true;
 249         in->restart = in->respawn = false;
 250         kill(in->proc.pid, SIGTERM);
 251 }
 252
 253 static void
 254 instance_restart(struct service_instance *in)
 255 {
 256         if (!in->proc.pending)
 257                 return;
 258         in->halt = false;
 259         in->restart = true;
 260         kill(in->proc.pid, SIGTERM);
 261 }
 262
 263 static bool
 264 instance_config_changed(struct service_instance *in, struct service_instance *in_new)
 265 {
 266         if (!in->valid)
 267                 return true;
 268
 269         if (!blob_attr_equal(in->command, in_new->command))
 270                 return true;
 271
 272         if (!blobmsg_list_equal(&in->env, &in_new->env))
 273                 return true;
 274
 275         if (!blobmsg_list_equal(&in->data, &in_new->data))
 276                 return true;
 277
 278         if (!blobmsg_list_equal(&in->netdev, &in_new->netdev))
 279                 return true;
 280
 281         if (!blobmsg_list_equal(&in->file, &in_new->file))
 282                 return true;
 283
 284         if (in->nice != in_new->nice)
 285                 return true;
 286
 287         if (!blobmsg_list_equal(&in->limits, &in_new->limits))
 288                 return true;
 289
 290         return false;
 291 }
 292
 293 static bool
 294 instance_netdev_cmp(struct blobmsg_list_node *l1, struct blobmsg_list_node *l2)
 295 {
 296         struct instance_netdev *n1 = container_of(l1, struct instance_netdev, node);
 297         struct instance_netdev *n2 = container_of(l2, struct instance_netdev, node);
 298
 299         return n1->ifindex == n2->ifindex;
 300 }
 301
 302 static void
 303 instance_netdev_update(struct blobmsg_list_node *l)
 304 {
 305         struct instance_netdev *n = container_of(l, struct instance_netdev, node);
 306
 307         n->ifindex = if_nametoindex(n->node.avl.key);
 308 }
 309
 310 static bool
 311 instance_file_cmp(struct blobmsg_list_node *l1, struct blobmsg_list_node *l2)
 312 {
 313         struct instance_file *f1 = container_of(l1, struct instance_file, node);
 314         struct instance_file *f2 = container_of(l2, struct instance_file, node);
 315
 316         return !memcmp(f1->md5, f2->md5, sizeof(f1->md5));
 317 }
 318
 319 static void
 320 instance_file_update(struct blobmsg_list_node *l)
 321 {
 322         struct instance_file *f = container_of(l, struct instance_file, node);
 323         md5_ctx_t md5;
 324         char buf[256];
 325         int len, fd;
 326
 327         memset(f->md5, 0, sizeof(f->md5));
 328
 329         fd = open(l->avl.key, O_RDONLY);
 330         if (fd < 0)
 331                 return;
 332
 333         md5_begin(&md5);
 334         do {
 335                 len = read(fd, buf, sizeof(buf));
 336                 if (len < 0) {
 337                         if (errno == EINTR)
 338                                 continue;
 339
 340                         break;
 341                 }
 342                 if (!len)
 343                         break;
 344
 345                 md5_hash(buf, len, &md5);
 346         } while(1);
 347
 348         md5_end(f->md5, &md5);
 349         close(fd);
 350 }
 351
 352 static bool
 353 instance_fill_array(struct blobmsg_list *l, struct blob_attr *cur, blobmsg_update_cb cb, bool array)
 354 {
 355         struct blobmsg_list_node *node;
 356
 357         if (!cur)
 358                 return true;
 359
 360         if (!blobmsg_check_attr_list(cur, BLOBMSG_TYPE_STRING))
 361                 return false;
 362
 363         blobmsg_list_fill(l, blobmsg_data(cur), blobmsg_data_len(cur), array);
 364         if (cb) {
 365                 blobmsg_list_for_each(l, node)
 366                         cb(node);
 367         }
 368         return true;
 369 }
 370
 371 static bool
 372 instance_config_parse(struct service_instance *in)
 373 {
 374         struct blob_attr *tb[__INSTANCE_ATTR_MAX];
 375         struct blob_attr *cur, *cur2;
 376         int argc = 0;
 377         int rem;
 378
 379         blobmsg_parse(instance_attr, __INSTANCE_ATTR_MAX, tb,
 380                 blobmsg_data(in->config), blobmsg_data_len(in->config));
 381
 382         cur = tb[INSTANCE_ATTR_COMMAND];
 383         if (!cur)
 384                 return false;
 385
 386         if (!blobmsg_check_attr_list(cur, BLOBMSG_TYPE_STRING))
 387                 return false;
 388
 389         blobmsg_for_each_attr(cur2, cur, rem) {
 390                 argc++;
 391                 break;
 392         }
 393         if (!argc)
 394                 return false;
 395
 396         in->command = cur;
 397
 398         if (tb[INSTANCE_ATTR_RESPAWN]) {
 399                 int i = 0;
 400                 uint32_t vals[3] = { 3600, 5, 5};
 401
 402                 blobmsg_for_each_attr(cur2, tb[INSTANCE_ATTR_RESPAWN], rem) {
 403                         if ((i >= 3) && (blobmsg_type(cur2) == BLOBMSG_TYPE_STRING))
 404                                 continue;
 405                         vals[i] = atoi(blobmsg_get_string(cur2));
 406                         i++;
 407                 }
 408                 in->respawn = true;
 409                 in->respawn_count = 0;
 410                 in->respawn_threshold = vals[0];
 411                 in->respawn_timeout = vals[1];
 412                 in->respawn_retry = vals[2];
 413         }
 414         if (tb[INSTANCE_ATTR_TRIGGER]) {
 415                 in->trigger = blob_memdup(tb[INSTANCE_ATTR_TRIGGER]);
 416                 if (!in->trigger)
 417                         return -1;
 418                 trigger_add(in->trigger, in);
 419         }
 420
 421         if (tb[INSTANCE_ATTR_WATCH]) {
 422                 blobmsg_for_each_attr(cur2, tb[INSTANCE_ATTR_WATCH], rem) {
 423                         if (blobmsg_type(cur2) != BLOBMSG_TYPE_STRING)
 424                                 continue;
 425                         DEBUG(3, "watch for %s\n", blobmsg_get_string(cur2));
 426                         watch_add(blobmsg_get_string(cur2), in);
 427                 }
 428         }
 429
 430         if ((cur = tb[INSTANCE_ATTR_NICE])) {
 431                 in->nice = (int8_t) blobmsg_get_u32(cur);
 432                 if (in->nice < -20 || in->nice > 20)
 433                         return false;
 434         }
 435
 436         if (!instance_fill_array(&in->env, tb[INSTANCE_ATTR_ENV], NULL, false))
 437                 return false;
 438
 439         if (!instance_fill_array(&in->data, tb[INSTANCE_ATTR_DATA], NULL, false))
 440                 return false;
 441
 442         if (!instance_fill_array(&in->netdev, tb[INSTANCE_ATTR_NETDEV], instance_netdev_update, true))
 443                 return false;
 444
 445         if (!instance_fill_array(&in->file, tb[INSTANCE_ATTR_FILE], instance_file_update, true))
 446                 return false;
 447
 448         if (!instance_fill_array(&in->limits, tb[INSTANCE_ATTR_LIMITS], NULL, false))
 449                 return false;
 450
 451         return true;
 452 }
 453
 454 static void
 455 instance_config_cleanup(struct service_instance *in)
 456 {
 457         blobmsg_list_free(&in->env);
 458         blobmsg_list_free(&in->data);
 459         blobmsg_list_free(&in->netdev);
 460         blobmsg_list_free(&in->file);
 461         blobmsg_list_free(&in->limits);
 462 }
 463
 464 static void
 465 instance_config_move(struct service_instance *in, struct service_instance *in_src)
 466 {
 467         instance_config_cleanup(in);
 468         blobmsg_list_move(&in->env, &in_src->env);
 469         blobmsg_list_move(&in->data, &in_src->data);
 470         blobmsg_list_move(&in->netdev, &in_src->netdev);
 471         blobmsg_list_move(&in->file, &in_src->file);
 472         blobmsg_list_move(&in->limits, &in_src->limits);
 473         in->trigger = in_src->trigger;
 474         in->command = in_src->command;
 475         in->name = in_src->name;
 476         in->node.avl.key = in_src->node.avl.key;
 477
 478         free(in->config);
 479         in->config = in_src->config;
 480         in_src->config = NULL;
 481 }
 482
 483 bool
 484 instance_update(struct service_instance *in, struct service_instance *in_new)
 485 {
 486         bool changed = instance_config_changed(in, in_new);
 487         bool running = in->proc.pending;
 488
 489         if (!changed && running)
 490                 return false;
 491
 492         if (!running) {
 493                 if (changed)
 494                         instance_config_move(in, in_new);
 495                 instance_start(in);
 496         } else {
 497                 instance_restart(in);
 498                 instance_config_move(in, in_new);
 499                 /* restart happens in the child callback handler */
 500         }
 501         return true;
 502 }
 503
 504 void
 505 instance_free(struct service_instance *in)
 506 {
 507         uloop_process_delete(&in->proc);
 508         uloop_timeout_cancel(&in->timeout);
 509         trigger_del(in);
 510         watch_del(in);
 511         free(in->trigger);
 512         instance_config_cleanup(in);
 513         free(in->config);
 514         free(in);
 515 }
 516
 517 void
 518 instance_init(struct service_instance *in, struct service *s, struct blob_attr *config)
 519 {
 520         config = blob_memdup(config);
 521         in->srv = s;
 522         in->name = blobmsg_name(config);
 523         in->config = config;
 524         in->timeout.cb = instance_timeout;
 525         in->proc.cb = instance_exit;
 526
 527         blobmsg_list_init(&in->netdev, struct instance_netdev, node, instance_netdev_cmp);
 528         blobmsg_list_init(&in->file, struct instance_file, node, instance_file_cmp);
 529         blobmsg_list_simple_init(&in->env);
 530         blobmsg_list_simple_init(&in->data);
 531         blobmsg_list_simple_init(&in->limits);
 532         in->valid = instance_config_parse(in);
 533 }
 534
 535 void instance_dump(struct blob_buf *b, struct service_instance *in, int verbose)
 536 {
 537         void *i;
 538
 539         i = blobmsg_open_table(b, in->name);
 540         blobmsg_add_u8(b, "running", in->proc.pending);
 541         if (in->proc.pending)
 542                 blobmsg_add_u32(b, "pid", in->proc.pid);
 543         blobmsg_add_blob(b, in->command);
 544
 545         if (!avl_is_empty(&in->env.avl)) {
 546                 struct blobmsg_list_node *var;
 547                 void *e = blobmsg_open_table(b, "env");
 548                 blobmsg_list_for_each(&in->env, var)
 549                         blobmsg_add_string(b, blobmsg_name(var->data), blobmsg_data(var->data));
 550                 blobmsg_close_table(b, e);
 551         }
 552
 553         if (!avl_is_empty(&in->limits.avl)) {
 554                 struct blobmsg_list_node *var;
 555                 void *e = blobmsg_open_table(b, "limits");
 556                 blobmsg_list_for_each(&in->limits, var)
 557                         blobmsg_add_string(b, blobmsg_name(var->data), blobmsg_data(var->data));
 558                 blobmsg_close_table(b, e);
 559         }
 560
 561         if (in->respawn) {
 562                 void *r = blobmsg_open_table(b, "respawn");
 563                 blobmsg_add_u32(b, "timeout", in->respawn_timeout);
 564                 blobmsg_add_u32(b, "threshold", in->respawn_threshold);
 565                 blobmsg_add_u32(b, "retry", in->respawn_retry);
 566                 blobmsg_close_table(b, r);
 567         }
 568
 569         if (verbose && in->trigger)
 570                 blobmsg_add_blob(b, in->trigger);
 571
 572         blobmsg_close_table(b, i);
 573 }