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 }
 192
 193 static void
 194 instance_timeout(struct uloop_timeout *t)
 195 {
 196         struct service_instance *in;
 197
 198         in = container_of(t, struct service_instance, timeout);
 199
 200         if (!in->halt && (in->restart || in->respawn))
 201                 instance_start(in);
 202 }
 203
 204 static void
 205 instance_exit(struct uloop_process *p, int ret)
 206 {
 207         struct service_instance *in;
 208         struct timespec tp;
 209         long runtime;
 210
 211         in = container_of(p, struct service_instance, proc);
 212
 213         clock_gettime(CLOCK_MONOTONIC, &tp);
 214         runtime = tp.tv_sec - in->start.tv_sec;
 215
 216         DEBUG(2, "Instance %s::%s exit with error code %d after %ld seconds\n", in->srv->name, in->name, ret, runtime);
 217         if (upgrade_running)
 218                 return;
 219
 220         uloop_timeout_cancel(&in->timeout);
 221         if (in->halt) {
 222                 /* no action */
 223         } else if (in->restart) {
 224                 instance_start(in);
 225         } else if (in->respawn) {
 226                 if (runtime < in->respawn_threshold)
 227                         in->respawn_count++;
 228                 else
 229                         in->respawn_count = 0;
 230                 if (in->respawn_count > in->respawn_retry && in->respawn_retry > 0 ) {
 231                         LOG("Instance %s::%s s in a crash loop %d crashes, %ld seconds since last crash\n",
 232                                                                 in->srv->name, in->name, in->respawn_count, runtime);
 233                         in->restart = in->respawn = 0;
 234                         in->halt = 1;
 235                 } else {
 236                         uloop_timeout_set(&in->timeout, in->respawn_timeout * 1000);
 237                 }
 238         }
 239 }
 240
 241 void
 242 instance_stop(struct service_instance *in)
 243 {
 244         if (!in->proc.pending)
 245                 return;
 246         in->halt = true;
 247         in->restart = in->respawn = false;
 248         kill(in->proc.pid, SIGTERM);
 249 }
 250
 251 static void
 252 instance_restart(struct service_instance *in)
 253 {
 254         if (!in->proc.pending)
 255                 return;
 256         in->halt = false;
 257         in->restart = true;
 258         kill(in->proc.pid, SIGTERM);
 259 }
 260
 261 static bool
 262 instance_config_changed(struct service_instance *in, struct service_instance *in_new)
 263 {
 264         if (!in->valid)
 265                 return true;
 266
 267         if (!blob_attr_equal(in->command, in_new->command))
 268                 return true;
 269
 270         if (!blobmsg_list_equal(&in->env, &in_new->env))
 271                 return true;
 272
 273         if (!blobmsg_list_equal(&in->data, &in_new->data))
 274                 return true;
 275
 276         if (!blobmsg_list_equal(&in->netdev, &in_new->netdev))
 277                 return true;
 278
 279         if (!blobmsg_list_equal(&in->file, &in_new->file))
 280                 return true;
 281
 282         if (in->nice != in_new->nice)
 283                 return true;
 284
 285         if (!blobmsg_list_equal(&in->limits, &in_new->limits))
 286                 return true;
 287
 288         return false;
 289 }
 290
 291 static bool
 292 instance_netdev_cmp(struct blobmsg_list_node *l1, struct blobmsg_list_node *l2)
 293 {
 294         struct instance_netdev *n1 = container_of(l1, struct instance_netdev, node);
 295         struct instance_netdev *n2 = container_of(l2, struct instance_netdev, node);
 296
 297         return n1->ifindex == n2->ifindex;
 298 }
 299
 300 static void
 301 instance_netdev_update(struct blobmsg_list_node *l)
 302 {
 303         struct instance_netdev *n = container_of(l, struct instance_netdev, node);
 304
 305         n->ifindex = if_nametoindex(n->node.avl.key);
 306 }
 307
 308 static bool
 309 instance_file_cmp(struct blobmsg_list_node *l1, struct blobmsg_list_node *l2)
 310 {
 311         struct instance_file *f1 = container_of(l1, struct instance_file, node);
 312         struct instance_file *f2 = container_of(l2, struct instance_file, node);
 313
 314         return !memcmp(f1->md5, f2->md5, sizeof(f1->md5));
 315 }
 316
 317 static void
 318 instance_file_update(struct blobmsg_list_node *l)
 319 {
 320         struct instance_file *f = container_of(l, struct instance_file, node);
 321         md5_ctx_t md5;
 322         char buf[256];
 323         int len, fd;
 324
 325         memset(f->md5, 0, sizeof(f->md5));
 326
 327         fd = open(l->avl.key, O_RDONLY);
 328         if (fd < 0)
 329                 return;
 330
 331         md5_begin(&md5);
 332         do {
 333                 len = read(fd, buf, sizeof(buf));
 334                 if (len < 0) {
 335                         if (errno == EINTR)
 336                                 continue;
 337
 338                         break;
 339                 }
 340                 if (!len)
 341                         break;
 342
 343                 md5_hash(buf, len, &md5);
 344         } while(1);
 345
 346         md5_end(f->md5, &md5);
 347         close(fd);
 348 }
 349
 350 static bool
 351 instance_fill_array(struct blobmsg_list *l, struct blob_attr *cur, blobmsg_update_cb cb, bool array)
 352 {
 353         struct blobmsg_list_node *node;
 354
 355         if (!cur)
 356                 return true;
 357
 358         if (!blobmsg_check_attr_list(cur, BLOBMSG_TYPE_STRING))
 359                 return false;
 360
 361         blobmsg_list_fill(l, blobmsg_data(cur), blobmsg_data_len(cur), array);
 362         if (cb) {
 363                 blobmsg_list_for_each(l, node)
 364                         cb(node);
 365         }
 366         return true;
 367 }
 368
 369 static bool
 370 instance_config_parse(struct service_instance *in)
 371 {
 372         struct blob_attr *tb[__INSTANCE_ATTR_MAX];
 373         struct blob_attr *cur, *cur2;
 374         int argc = 0;
 375         int rem;
 376
 377         blobmsg_parse(instance_attr, __INSTANCE_ATTR_MAX, tb,
 378                 blobmsg_data(in->config), blobmsg_data_len(in->config));
 379
 380         cur = tb[INSTANCE_ATTR_COMMAND];
 381         if (!cur)
 382                 return false;
 383
 384         if (!blobmsg_check_attr_list(cur, BLOBMSG_TYPE_STRING))
 385                 return false;
 386
 387         blobmsg_for_each_attr(cur2, cur, rem) {
 388                 argc++;
 389                 break;
 390         }
 391         if (!argc)
 392                 return false;
 393
 394         in->command = cur;
 395
 396         if (tb[INSTANCE_ATTR_RESPAWN]) {
 397                 int i = 0;
 398                 uint32_t vals[3] = { 3600, 5, 5};
 399
 400                 blobmsg_for_each_attr(cur2, tb[INSTANCE_ATTR_RESPAWN], rem) {
 401                         if ((i >= 3) && (blobmsg_type(cur2) == BLOBMSG_TYPE_STRING))
 402                                 continue;
 403                         vals[i] = atoi(blobmsg_get_string(cur2));
 404                         i++;
 405                 }
 406                 in->respawn = true;
 407                 in->respawn_count = 0;
 408                 in->respawn_threshold = vals[0];
 409                 in->respawn_timeout = vals[1];
 410                 in->respawn_retry = vals[2];
 411         }
 412         if (tb[INSTANCE_ATTR_TRIGGER]) {
 413                 in->trigger = blob_memdup(tb[INSTANCE_ATTR_TRIGGER]);
 414                 if (!in->trigger)
 415                         return -1;
 416                 trigger_add(in->trigger, in);
 417         }
 418
 419         if (tb[INSTANCE_ATTR_WATCH]) {
 420                 blobmsg_for_each_attr(cur2, tb[INSTANCE_ATTR_WATCH], rem) {
 421                         if (blobmsg_type(cur2) != BLOBMSG_TYPE_STRING)
 422                                 continue;
 423                         DEBUG(3, "watch for %s\n", blobmsg_get_string(cur2));
 424                         watch_add(blobmsg_get_string(cur2), in);
 425                 }
 426         }
 427
 428         if ((cur = tb[INSTANCE_ATTR_NICE])) {
 429                 in->nice = (int8_t) blobmsg_get_u32(cur);
 430                 if (in->nice < -20 || in->nice > 20)
 431                         return false;
 432         }
 433
 434         if (!instance_fill_array(&in->env, tb[INSTANCE_ATTR_ENV], NULL, false))
 435                 return false;
 436
 437         if (!instance_fill_array(&in->data, tb[INSTANCE_ATTR_DATA], NULL, false))
 438                 return false;
 439
 440         if (!instance_fill_array(&in->netdev, tb[INSTANCE_ATTR_NETDEV], instance_netdev_update, true))
 441                 return false;
 442
 443         if (!instance_fill_array(&in->file, tb[INSTANCE_ATTR_FILE], instance_file_update, true))
 444                 return false;
 445
 446         if (!instance_fill_array(&in->limits, tb[INSTANCE_ATTR_LIMITS], NULL, false))
 447                 return false;
 448
 449         return true;
 450 }
 451
 452 static void
 453 instance_config_cleanup(struct service_instance *in)
 454 {
 455         blobmsg_list_free(&in->env);
 456         blobmsg_list_free(&in->data);
 457         blobmsg_list_free(&in->netdev);
 458         blobmsg_list_free(&in->file);
 459         blobmsg_list_free(&in->limits);
 460 }
 461
 462 static void
 463 instance_config_move(struct service_instance *in, struct service_instance *in_src)
 464 {
 465         instance_config_cleanup(in);
 466         blobmsg_list_move(&in->env, &in_src->env);
 467         blobmsg_list_move(&in->data, &in_src->data);
 468         blobmsg_list_move(&in->netdev, &in_src->netdev);
 469         blobmsg_list_move(&in->file, &in_src->file);
 470         blobmsg_list_move(&in->limits, &in_src->limits);
 471         in->trigger = in_src->trigger;
 472         in->command = in_src->command;
 473         in->name = in_src->name;
 474         in->node.avl.key = in_src->node.avl.key;
 475
 476         free(in->config);
 477         in->config = in_src->config;
 478         in_src->config = NULL;
 479 }
 480
 481 bool
 482 instance_update(struct service_instance *in, struct service_instance *in_new)
 483 {
 484         bool changed = instance_config_changed(in, in_new);
 485         bool running = in->proc.pending;
 486
 487         if (!changed && running)
 488                 return false;
 489
 490         if (!running) {
 491                 if (changed)
 492                         instance_config_move(in, in_new);
 493                 instance_start(in);
 494         } else {
 495                 instance_restart(in);
 496                 instance_config_move(in, in_new);
 497                 /* restart happens in the child callback handler */
 498         }
 499         return true;
 500 }
 501
 502 void
 503 instance_free(struct service_instance *in)
 504 {
 505         uloop_process_delete(&in->proc);
 506         uloop_timeout_cancel(&in->timeout);
 507         trigger_del(in);
 508         watch_del(in);
 509         free(in->trigger);
 510         instance_config_cleanup(in);
 511         free(in->config);
 512         free(in);
 513 }
 514
 515 void
 516 instance_init(struct service_instance *in, struct service *s, struct blob_attr *config)
 517 {
 518         config = blob_memdup(config);
 519         in->srv = s;
 520         in->name = blobmsg_name(config);
 521         in->config = config;
 522         in->timeout.cb = instance_timeout;
 523         in->proc.cb = instance_exit;
 524
 525         blobmsg_list_init(&in->netdev, struct instance_netdev, node, instance_netdev_cmp);
 526         blobmsg_list_init(&in->file, struct instance_file, node, instance_file_cmp);
 527         blobmsg_list_simple_init(&in->env);
 528         blobmsg_list_simple_init(&in->data);
 529         blobmsg_list_simple_init(&in->limits);
 530         in->valid = instance_config_parse(in);
 531 }
 532
 533 void instance_dump(struct blob_buf *b, struct service_instance *in, int verbose)
 534 {
 535         void *i;
 536
 537         i = blobmsg_open_table(b, in->name);
 538         blobmsg_add_u8(b, "running", in->proc.pending);
 539         if (in->proc.pending)
 540                 blobmsg_add_u32(b, "pid", in->proc.pid);
 541         blobmsg_add_blob(b, in->command);
 542
 543         if (!avl_is_empty(&in->env.avl)) {
 544                 struct blobmsg_list_node *var;
 545                 void *e = blobmsg_open_table(b, "env");
 546                 blobmsg_list_for_each(&in->env, var)
 547                         blobmsg_add_string(b, blobmsg_name(var->data), blobmsg_data(var->data));
 548                 blobmsg_close_table(b, e);
 549         }
 550
 551         if (!avl_is_empty(&in->limits.avl)) {
 552                 struct blobmsg_list_node *var;
 553                 void *e = blobmsg_open_table(b, "limits");
 554                 blobmsg_list_for_each(&in->limits, var)
 555                         blobmsg_add_string(b, blobmsg_name(var->data), blobmsg_data(var->data));
 556                 blobmsg_close_table(b, e);
 557         }
 558
 559         if (in->respawn) {
 560                 void *r = blobmsg_open_table(b, "respawn");
 561                 blobmsg_add_u32(b, "timeout", in->respawn_timeout);
 562                 blobmsg_add_u32(b, "threshold", in->respawn_threshold);
 563                 blobmsg_add_u32(b, "retry", in->respawn_retry);
 564                 blobmsg_close_table(b, r);
 565         }
 566
 567         if (verbose && in->trigger)
 568                 blobmsg_add_blob(b, in->trigger);
 569
 570         blobmsg_close_table(b, i);
 571 }