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 "../procd.h"
  24
  25 #include "service.h"
  26 #include "instance.h"
  27
  28 #include "../utils/md5.h"
  29
  30 enum {
  31         INSTANCE_ATTR_COMMAND,
  32         INSTANCE_ATTR_ENV,
  33         INSTANCE_ATTR_DATA,
  34         INSTANCE_ATTR_NETDEV,
  35         INSTANCE_ATTR_FILE,
  36         INSTANCE_ATTR_TRIGGER,
  37         INSTANCE_ATTR_RESPAWN,
  38         INSTANCE_ATTR_NICE,
  39         __INSTANCE_ATTR_MAX
  40 };
  41
  42 static const struct blobmsg_policy instance_attr[__INSTANCE_ATTR_MAX] = {
  43         [INSTANCE_ATTR_COMMAND] = { "command", BLOBMSG_TYPE_ARRAY },
  44         [INSTANCE_ATTR_ENV] = { "env", BLOBMSG_TYPE_TABLE },
  45         [INSTANCE_ATTR_DATA] = { "data", BLOBMSG_TYPE_TABLE },
  46         [INSTANCE_ATTR_NETDEV] = { "netdev", BLOBMSG_TYPE_ARRAY },
  47         [INSTANCE_ATTR_FILE] = { "file", BLOBMSG_TYPE_ARRAY },
  48         [INSTANCE_ATTR_TRIGGER] = { "triggers", BLOBMSG_TYPE_ARRAY },
  49         [INSTANCE_ATTR_RESPAWN] = { "respawn", BLOBMSG_TYPE_ARRAY },
  50         [INSTANCE_ATTR_NICE] = { "nice", BLOBMSG_TYPE_INT32 },
  51 };
  52
  53 struct instance_netdev {
  54         struct blobmsg_list_node node;
  55         int ifindex;
  56 };
  57
  58 struct instance_file {
  59         struct blobmsg_list_node node;
  60         uint32_t md5[4];
  61 };
  62
  63 static void
  64 instance_run(struct service_instance *in)
  65 {
  66         struct blobmsg_list_node *var;
  67         struct blob_attr *cur;
  68         char **argv;
  69         int argc = 1; /* NULL terminated */
  70         int rem, fd;
  71
  72         if (in->nice)
  73                 setpriority(PRIO_PROCESS, 0, in->nice);
  74
  75         blobmsg_for_each_attr(cur, in->command, rem)
  76                 argc++;
  77
  78         blobmsg_list_for_each(&in->env, var)
  79                 setenv(blobmsg_name(var->data), blobmsg_data(var->data), 1);
  80
  81         argv = alloca(sizeof(char *) * argc);
  82         argc = 0;
  83
  84         blobmsg_for_each_attr(cur, in->command, rem)
  85                 argv[argc++] = blobmsg_data(cur);
  86
  87         argv[argc] = NULL;
  88         fd = open("/dev/null", O_RDWR);
  89         if (fd > -1) {
  90                 dup2(fd, STDIN_FILENO);
  91                 dup2(fd, STDOUT_FILENO);
  92                 dup2(fd, STDERR_FILENO);
  93                 if (fd > STDERR_FILENO)
  94                         close(fd);
  95         }
  96         execvp(argv[0], argv);
  97         exit(127);
  98 }
  99
 100 void
 101 instance_start(struct service_instance *in)
 102 {
 103         int pid;
 104
 105         if (in->proc.pending)
 106                 return;
 107
 108         in->restart = false;
 109         in->halt = !in->respawn;
 110
 111         if (!in->valid)
 112                 return;
 113
 114         pid = fork();
 115         if (pid < 0)
 116                 return;
 117
 118         if (!pid) {
 119                 uloop_done();
 120                 instance_run(in);
 121                 return;
 122         }
 123
 124         DEBUG(2, "Started instance %s::%s\n", in->srv->name, in->name);
 125         in->proc.pid = pid;
 126         clock_gettime(CLOCK_MONOTONIC, &in->start);
 127         uloop_process_add(&in->proc);
 128 }
 129
 130 static void
 131 instance_timeout(struct uloop_timeout *t)
 132 {
 133         struct service_instance *in;
 134
 135         in = container_of(t, struct service_instance, timeout);
 136
 137         if (!in->halt && (in->restart || in->respawn))
 138                 instance_start(in);
 139 }
 140
 141 static void
 142 instance_exit(struct uloop_process *p, int ret)
 143 {
 144         struct service_instance *in;
 145         struct timespec tp;
 146         long runtime;
 147
 148         in = container_of(p, struct service_instance, proc);
 149
 150         clock_gettime(CLOCK_MONOTONIC, &tp);
 151         runtime = tp.tv_sec - in->start.tv_sec;
 152
 153         DEBUG(2, "Instance %s::%s exit with error code %d after %ld seconds\n", in->srv->name, in->name, ret, runtime);
 154         if (upgrade_running)
 155                 return;
 156
 157         uloop_timeout_cancel(&in->timeout);
 158         if (in->halt) {
 159                 /* no action */
 160         } else if (in->restart) {
 161                 instance_start(in);
 162         } else if (in->respawn) {
 163                 if (runtime < in->respawn_threshold)
 164                         in->respawn_count++;
 165                 else
 166                         in->respawn_count = 0;
 167                 if (in->respawn_count > in->respawn_retry && in->respawn_retry > 0 ) {
 168                         LOG("Instance %s::%s s in a crash loop %d crashes, %ld seconds since last crash\n",
 169                                                                 in->srv->name, in->name, in->respawn_count, runtime);
 170                         in->restart = in->respawn = 0;
 171                         in->halt = 1;
 172                 } else {
 173                         uloop_timeout_set(&in->timeout, in->respawn_timeout * 1000);
 174                 }
 175         }
 176 }
 177
 178 void
 179 instance_stop(struct service_instance *in)
 180 {
 181         if (!in->proc.pending)
 182                 return;
 183         in->halt = true;
 184         in->restart = in->respawn = false;
 185         kill(in->proc.pid, SIGTERM);
 186 }
 187
 188 static void
 189 instance_restart(struct service_instance *in)
 190 {
 191         if (!in->proc.pending)
 192                 return;
 193         in->halt = false;
 194         in->restart = true;
 195         kill(in->proc.pid, SIGTERM);
 196 }
 197
 198 static bool
 199 instance_config_changed(struct service_instance *in, struct service_instance *in_new)
 200 {
 201         if (!in->valid)
 202                 return true;
 203
 204         if (!blob_attr_equal(in->command, in_new->command))
 205                 return true;
 206
 207         if (!blobmsg_list_equal(&in->env, &in_new->env))
 208                 return true;
 209
 210         if (!blobmsg_list_equal(&in->data, &in_new->data))
 211                 return true;
 212
 213         if (!blobmsg_list_equal(&in->netdev, &in_new->netdev))
 214                 return true;
 215
 216         if (!blobmsg_list_equal(&in->file, &in_new->file))
 217                 return true;
 218
 219         if (in->nice != in_new->nice)
 220                 return true;
 221
 222         return false;
 223 }
 224
 225 static bool
 226 instance_netdev_cmp(struct blobmsg_list_node *l1, struct blobmsg_list_node *l2)
 227 {
 228         struct instance_netdev *n1 = container_of(l1, struct instance_netdev, node);
 229         struct instance_netdev *n2 = container_of(l2, struct instance_netdev, node);
 230
 231         return n1->ifindex == n2->ifindex;
 232 }
 233
 234 static void
 235 instance_netdev_update(struct blobmsg_list_node *l)
 236 {
 237         struct instance_netdev *n = container_of(l, struct instance_netdev, node);
 238
 239         n->ifindex = if_nametoindex(n->node.avl.key);
 240 }
 241
 242 static bool
 243 instance_file_cmp(struct blobmsg_list_node *l1, struct blobmsg_list_node *l2)
 244 {
 245         struct instance_file *f1 = container_of(l1, struct instance_file, node);
 246         struct instance_file *f2 = container_of(l2, struct instance_file, node);
 247
 248         return !memcmp(f1->md5, f2->md5, sizeof(f1->md5));
 249 }
 250
 251 static void
 252 instance_file_update(struct blobmsg_list_node *l)
 253 {
 254         struct instance_file *f = container_of(l, struct instance_file, node);
 255         md5_ctx_t md5;
 256         char buf[256];
 257         int len, fd;
 258
 259         memset(f->md5, 0, sizeof(f->md5));
 260
 261         fd = open(l->avl.key, O_RDONLY);
 262         if (fd < 0)
 263                 return;
 264
 265         md5_begin(&md5);
 266         do {
 267                 len = read(fd, buf, sizeof(buf));
 268                 if (len < 0) {
 269                         if (errno == EINTR)
 270                                 continue;
 271
 272                         break;
 273                 }
 274                 if (!len)
 275                         break;
 276
 277                 md5_hash(buf, len, &md5);
 278         } while(1);
 279
 280         md5_end(f->md5, &md5);
 281         close(fd);
 282 }
 283
 284 static bool
 285 instance_fill_array(struct blobmsg_list *l, struct blob_attr *cur, blobmsg_update_cb cb, bool array)
 286 {
 287         struct blobmsg_list_node *node;
 288
 289         if (!cur)
 290                 return true;
 291
 292         if (!blobmsg_check_attr_list(cur, BLOBMSG_TYPE_STRING))
 293                 return false;
 294
 295         blobmsg_list_fill(l, blobmsg_data(cur), blobmsg_data_len(cur), array);
 296         if (cb) {
 297                 blobmsg_list_for_each(l, node)
 298                         cb(node);
 299         }
 300         return true;
 301 }
 302
 303 static bool
 304 instance_config_parse(struct service_instance *in)
 305 {
 306         struct blob_attr *tb[__INSTANCE_ATTR_MAX];
 307         struct blob_attr *cur, *cur2;
 308         int argc = 0;
 309         int rem;
 310
 311         blobmsg_parse(instance_attr, __INSTANCE_ATTR_MAX, tb,
 312                 blobmsg_data(in->config), blobmsg_data_len(in->config));
 313
 314         cur = tb[INSTANCE_ATTR_COMMAND];
 315         if (!cur)
 316                 return false;
 317
 318         if (!blobmsg_check_attr_list(cur, BLOBMSG_TYPE_STRING))
 319                 return false;
 320
 321         blobmsg_for_each_attr(cur2, cur, rem) {
 322                 argc++;
 323                 break;
 324         }
 325         if (!argc)
 326                 return false;
 327
 328         in->command = cur;
 329
 330         if (tb[INSTANCE_ATTR_RESPAWN]) {
 331                 int i = 0;
 332                 uint32_t vals[3] = { 3600, 5, 5};
 333
 334                 blobmsg_for_each_attr(cur2, tb[INSTANCE_ATTR_RESPAWN], rem) {
 335                         if ((i >= 3) && (blobmsg_type(cur2) == BLOBMSG_TYPE_STRING))
 336                                 continue;
 337                         vals[i] = atoi(blobmsg_get_string(cur2));
 338                         i++;
 339                 }
 340                 in->respawn = true;
 341                 in->respawn_count = 0;
 342                 in->respawn_threshold = vals[0];
 343                 in->respawn_timeout = vals[1];
 344                 in->respawn_retry = vals[2];
 345         }
 346         if (tb[INSTANCE_ATTR_TRIGGER]) {
 347                 in->trigger = malloc(blob_pad_len(tb[INSTANCE_ATTR_TRIGGER]));
 348                 if (!in->trigger)
 349                         return -1;
 350                 memcpy(in->trigger, tb[INSTANCE_ATTR_TRIGGER], blob_pad_len(tb[INSTANCE_ATTR_TRIGGER]));
 351                 trigger_add(in->trigger, in);
 352         }
 353
 354         if ((cur = tb[INSTANCE_ATTR_NICE])) {
 355                 in->nice = (int8_t) blobmsg_get_u32(cur);
 356                 if (in->nice < -20 || in->nice > 20)
 357                         return false;
 358         }
 359
 360         if (!instance_fill_array(&in->env, tb[INSTANCE_ATTR_ENV], NULL, false))
 361                 return false;
 362
 363         if (!instance_fill_array(&in->data, tb[INSTANCE_ATTR_DATA], NULL, false))
 364                 return false;
 365
 366         if (!instance_fill_array(&in->netdev, tb[INSTANCE_ATTR_NETDEV], instance_netdev_update, true))
 367                 return false;
 368
 369         if (!instance_fill_array(&in->file, tb[INSTANCE_ATTR_FILE], instance_file_update, true))
 370                 return false;
 371
 372         return true;
 373 }
 374
 375 static void
 376 instance_config_cleanup(struct service_instance *in)
 377 {
 378         blobmsg_list_free(&in->env);
 379         blobmsg_list_free(&in->data);
 380         blobmsg_list_free(&in->netdev);
 381 }
 382
 383 static void
 384 instance_config_move(struct service_instance *in, struct service_instance *in_src)
 385 {
 386         instance_config_cleanup(in);
 387         blobmsg_list_move(&in->env, &in_src->env);
 388         blobmsg_list_move(&in->data, &in_src->data);
 389         blobmsg_list_move(&in->netdev, &in_src->netdev);
 390         in->trigger = in_src->trigger;
 391         in->command = in_src->command;
 392         in->name = in_src->name;
 393         in->node.avl.key = in_src->node.avl.key;
 394
 395         free(in->config);
 396         in->config = in_src->config;
 397         in_src->config = NULL;
 398 }
 399
 400 bool
 401 instance_update(struct service_instance *in, struct service_instance *in_new)
 402 {
 403         bool changed = instance_config_changed(in, in_new);
 404         bool running = in->proc.pending;
 405
 406         if (!changed && running)
 407                 return false;
 408
 409         if (!running) {
 410                 if (changed)
 411                         instance_config_move(in, in_new);
 412                 instance_start(in);
 413         } else {
 414                 instance_restart(in);
 415                 instance_config_move(in, in_new);
 416                 /* restart happens in the child callback handler */
 417         }
 418         return true;
 419 }
 420
 421 void
 422 instance_free(struct service_instance *in)
 423 {
 424         uloop_process_delete(&in->proc);
 425         uloop_timeout_cancel(&in->timeout);
 426         trigger_del(in);
 427         free(in->trigger);
 428         instance_config_cleanup(in);
 429         free(in->config);
 430         free(in);
 431 }
 432
 433 void
 434 instance_init(struct service_instance *in, struct service *s, struct blob_attr *config)
 435 {
 436         config = blob_memdup(config);
 437         in->srv = s;
 438         in->name = blobmsg_name(config);
 439         in->config = config;
 440         in->timeout.cb = instance_timeout;
 441         in->proc.cb = instance_exit;
 442
 443         blobmsg_list_init(&in->netdev, struct instance_netdev, node, instance_netdev_cmp);
 444         blobmsg_list_init(&in->file, struct instance_file, node, instance_file_cmp);
 445         blobmsg_list_simple_init(&in->env);
 446         blobmsg_list_simple_init(&in->data);
 447         in->valid = instance_config_parse(in);
 448 }
 449
 450 void instance_dump(struct blob_buf *b, struct service_instance *in, int verbose)
 451 {
 452         void *i;
 453
 454         i = blobmsg_open_table(b, in->name);
 455         blobmsg_add_u8(b, "running", in->proc.pending);
 456         if (in->proc.pending)
 457                 blobmsg_add_u32(b, "pid", in->proc.pid);
 458         blobmsg_add_blob(b, in->command);
 459
 460         if (!avl_is_empty(&in->env.avl)) {
 461                 struct blobmsg_list_node *var;
 462                 void *e = blobmsg_open_table(b, "env");
 463                 blobmsg_list_for_each(&in->env, var)
 464                         blobmsg_add_string(b, blobmsg_name(var->data), blobmsg_data(var->data));
 465                 blobmsg_close_table(b, e);
 466         }
 467
 468         if (in->respawn) {
 469                 void *r = blobmsg_open_table(b, "respawn");
 470                 blobmsg_add_u32(b, "timeout", in->respawn_timeout);
 471                 blobmsg_add_u32(b, "threshold", in->respawn_threshold);
 472                 blobmsg_add_u32(b, "retry", in->respawn_retry);
 473                 blobmsg_close_table(b, r);
 474         }
 475
 476         if (verbose && in->trigger)
 477                 blobmsg_add_blob(b, in->trigger);
 478
 479         blobmsg_close_table(b, i);
 480 }