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_MAX
  41 };
  42
  43 static const struct blobmsg_policy instance_attr[__INSTANCE_ATTR_MAX] = {
  44         [INSTANCE_ATTR_COMMAND] = { "command", BLOBMSG_TYPE_ARRAY },
  45         [INSTANCE_ATTR_ENV] = { "env", BLOBMSG_TYPE_TABLE },
  46         [INSTANCE_ATTR_DATA] = { "data", BLOBMSG_TYPE_TABLE },
  47         [INSTANCE_ATTR_NETDEV] = { "netdev", BLOBMSG_TYPE_ARRAY },
  48         [INSTANCE_ATTR_FILE] = { "file", BLOBMSG_TYPE_ARRAY },
  49         [INSTANCE_ATTR_TRIGGER] = { "triggers", BLOBMSG_TYPE_ARRAY },
  50         [INSTANCE_ATTR_RESPAWN] = { "respawn", BLOBMSG_TYPE_ARRAY },
  51         [INSTANCE_ATTR_NICE] = { "nice", BLOBMSG_TYPE_INT32 },
  52 };
  53
  54 struct instance_netdev {
  55         struct blobmsg_list_node node;
  56         int ifindex;
  57 };
  58
  59 struct instance_file {
  60         struct blobmsg_list_node node;
  61         uint32_t md5[4];
  62 };
  63
  64 static void
  65 instance_run(struct service_instance *in)
  66 {
  67         struct blobmsg_list_node *var;
  68         struct blob_attr *cur;
  69         char **argv;
  70         int argc = 1; /* NULL terminated */
  71         int rem, fd;
  72
  73         if (in->nice)
  74                 setpriority(PRIO_PROCESS, 0, in->nice);
  75
  76         blobmsg_for_each_attr(cur, in->command, rem)
  77                 argc++;
  78
  79         blobmsg_list_for_each(&in->env, var)
  80                 setenv(blobmsg_name(var->data), blobmsg_data(var->data), 1);
  81
  82         argv = alloca(sizeof(char *) * argc);
  83         argc = 0;
  84
  85         blobmsg_for_each_attr(cur, in->command, rem)
  86                 argv[argc++] = blobmsg_data(cur);
  87
  88         argv[argc] = NULL;
  89         fd = open("/dev/null", O_RDWR);
  90         if (fd > -1) {
  91                 dup2(fd, STDIN_FILENO);
  92                 dup2(fd, STDOUT_FILENO);
  93                 dup2(fd, STDERR_FILENO);
  94                 if (fd > STDERR_FILENO)
  95                         close(fd);
  96         }
  97         execvp(argv[0], argv);
  98         exit(127);
  99 }
 100
 101 void
 102 instance_start(struct service_instance *in)
 103 {
 104         int pid;
 105
 106         if (in->proc.pending)
 107                 return;
 108
 109         in->restart = false;
 110         in->halt = !in->respawn;
 111
 112         if (!in->valid)
 113                 return;
 114
 115         pid = fork();
 116         if (pid < 0)
 117                 return;
 118
 119         if (!pid) {
 120                 uloop_done();
 121                 instance_run(in);
 122                 return;
 123         }
 124
 125         DEBUG(2, "Started instance %s::%s\n", in->srv->name, in->name);
 126         in->proc.pid = pid;
 127         clock_gettime(CLOCK_MONOTONIC, &in->start);
 128         uloop_process_add(&in->proc);
 129 }
 130
 131 static void
 132 instance_timeout(struct uloop_timeout *t)
 133 {
 134         struct service_instance *in;
 135
 136         in = container_of(t, struct service_instance, timeout);
 137
 138         if (!in->halt && (in->restart || in->respawn))
 139                 instance_start(in);
 140 }
 141
 142 static void
 143 instance_exit(struct uloop_process *p, int ret)
 144 {
 145         struct service_instance *in;
 146         struct timespec tp;
 147         long runtime;
 148
 149         in = container_of(p, struct service_instance, proc);
 150
 151         clock_gettime(CLOCK_MONOTONIC, &tp);
 152         runtime = tp.tv_sec - in->start.tv_sec;
 153
 154         DEBUG(2, "Instance %s::%s exit with error code %d after %ld seconds\n", in->srv->name, in->name, ret, runtime);
 155         if (upgrade_running)
 156                 return;
 157
 158         uloop_timeout_cancel(&in->timeout);
 159         if (in->halt) {
 160                 /* no action */
 161         } else if (in->restart) {
 162                 instance_start(in);
 163         } else if (in->respawn) {
 164                 if (runtime < in->respawn_threshold)
 165                         in->respawn_count++;
 166                 else
 167                         in->respawn_count = 0;
 168                 if (in->respawn_count > in->respawn_retry && in->respawn_retry > 0 ) {
 169                         LOG("Instance %s::%s s in a crash loop %d crashes, %ld seconds since last crash\n",
 170                                                                 in->srv->name, in->name, in->respawn_count, runtime);
 171                         in->restart = in->respawn = 0;
 172                         in->halt = 1;
 173                 } else {
 174                         uloop_timeout_set(&in->timeout, in->respawn_timeout * 1000);
 175                 }
 176         }
 177 }
 178
 179 void
 180 instance_stop(struct service_instance *in)
 181 {
 182         if (!in->proc.pending)
 183                 return;
 184         in->halt = true;
 185         in->restart = in->respawn = false;
 186         kill(in->proc.pid, SIGTERM);
 187 }
 188
 189 static void
 190 instance_restart(struct service_instance *in)
 191 {
 192         if (!in->proc.pending)
 193                 return;
 194         in->halt = false;
 195         in->restart = true;
 196         kill(in->proc.pid, SIGTERM);
 197 }
 198
 199 static bool
 200 instance_config_changed(struct service_instance *in, struct service_instance *in_new)
 201 {
 202         if (!in->valid)
 203                 return true;
 204
 205         if (!blob_attr_equal(in->command, in_new->command))
 206                 return true;
 207
 208         if (!blobmsg_list_equal(&in->env, &in_new->env))
 209                 return true;
 210
 211         if (!blobmsg_list_equal(&in->data, &in_new->data))
 212                 return true;
 213
 214         if (!blobmsg_list_equal(&in->netdev, &in_new->netdev))
 215                 return true;
 216
 217         if (!blobmsg_list_equal(&in->file, &in_new->file))
 218                 return true;
 219
 220         if (in->nice != in_new->nice)
 221                 return true;
 222
 223         return false;
 224 }
 225
 226 static bool
 227 instance_netdev_cmp(struct blobmsg_list_node *l1, struct blobmsg_list_node *l2)
 228 {
 229         struct instance_netdev *n1 = container_of(l1, struct instance_netdev, node);
 230         struct instance_netdev *n2 = container_of(l2, struct instance_netdev, node);
 231
 232         return n1->ifindex == n2->ifindex;
 233 }
 234
 235 static void
 236 instance_netdev_update(struct blobmsg_list_node *l)
 237 {
 238         struct instance_netdev *n = container_of(l, struct instance_netdev, node);
 239
 240         n->ifindex = if_nametoindex(n->node.avl.key);
 241 }
 242
 243 static bool
 244 instance_file_cmp(struct blobmsg_list_node *l1, struct blobmsg_list_node *l2)
 245 {
 246         struct instance_file *f1 = container_of(l1, struct instance_file, node);
 247         struct instance_file *f2 = container_of(l2, struct instance_file, node);
 248
 249         return !memcmp(f1->md5, f2->md5, sizeof(f1->md5));
 250 }
 251
 252 static void
 253 instance_file_update(struct blobmsg_list_node *l)
 254 {
 255         struct instance_file *f = container_of(l, struct instance_file, node);
 256         md5_ctx_t md5;
 257         char buf[256];
 258         int len, fd;
 259
 260         memset(f->md5, 0, sizeof(f->md5));
 261
 262         fd = open(l->avl.key, O_RDONLY);
 263         if (fd < 0)
 264                 return;
 265
 266         md5_begin(&md5);
 267         do {
 268                 len = read(fd, buf, sizeof(buf));
 269                 if (len < 0) {
 270                         if (errno == EINTR)
 271                                 continue;
 272
 273                         break;
 274                 }
 275                 if (!len)
 276                         break;
 277
 278                 md5_hash(buf, len, &md5);
 279         } while(1);
 280
 281         md5_end(f->md5, &md5);
 282         close(fd);
 283 }
 284
 285 static bool
 286 instance_fill_array(struct blobmsg_list *l, struct blob_attr *cur, blobmsg_update_cb cb, bool array)
 287 {
 288         struct blobmsg_list_node *node;
 289
 290         if (!cur)
 291                 return true;
 292
 293         if (!blobmsg_check_attr_list(cur, BLOBMSG_TYPE_STRING))
 294                 return false;
 295
 296         blobmsg_list_fill(l, blobmsg_data(cur), blobmsg_data_len(cur), array);
 297         if (cb) {
 298                 blobmsg_list_for_each(l, node)
 299                         cb(node);
 300         }
 301         return true;
 302 }
 303
 304 static bool
 305 instance_config_parse(struct service_instance *in)
 306 {
 307         struct blob_attr *tb[__INSTANCE_ATTR_MAX];
 308         struct blob_attr *cur, *cur2;
 309         int argc = 0;
 310         int rem;
 311
 312         blobmsg_parse(instance_attr, __INSTANCE_ATTR_MAX, tb,
 313                 blobmsg_data(in->config), blobmsg_data_len(in->config));
 314
 315         cur = tb[INSTANCE_ATTR_COMMAND];
 316         if (!cur)
 317                 return false;
 318
 319         if (!blobmsg_check_attr_list(cur, BLOBMSG_TYPE_STRING))
 320                 return false;
 321
 322         blobmsg_for_each_attr(cur2, cur, rem) {
 323                 argc++;
 324                 break;
 325         }
 326         if (!argc)
 327                 return false;
 328
 329         in->command = cur;
 330
 331         if (tb[INSTANCE_ATTR_RESPAWN]) {
 332                 int i = 0;
 333                 uint32_t vals[3] = { 3600, 5, 5};
 334
 335                 blobmsg_for_each_attr(cur2, tb[INSTANCE_ATTR_RESPAWN], rem) {
 336                         if ((i >= 3) && (blobmsg_type(cur2) == BLOBMSG_TYPE_STRING))
 337                                 continue;
 338                         vals[i] = atoi(blobmsg_get_string(cur2));
 339                         i++;
 340                 }
 341                 in->respawn = true;
 342                 in->respawn_count = 0;
 343                 in->respawn_threshold = vals[0];
 344                 in->respawn_timeout = vals[1];
 345                 in->respawn_retry = vals[2];
 346         }
 347         if (tb[INSTANCE_ATTR_TRIGGER]) {
 348                 in->trigger = malloc(blob_pad_len(tb[INSTANCE_ATTR_TRIGGER]));
 349                 if (!in->trigger)
 350                         return -1;
 351                 memcpy(in->trigger, tb[INSTANCE_ATTR_TRIGGER], blob_pad_len(tb[INSTANCE_ATTR_TRIGGER]));
 352                 trigger_add(in->trigger, in);
 353         }
 354
 355         if ((cur = tb[INSTANCE_ATTR_NICE])) {
 356                 in->nice = (int8_t) blobmsg_get_u32(cur);
 357                 if (in->nice < -20 || in->nice > 20)
 358                         return false;
 359         }
 360
 361         if (!instance_fill_array(&in->env, tb[INSTANCE_ATTR_ENV], NULL, false))
 362                 return false;
 363
 364         if (!instance_fill_array(&in->data, tb[INSTANCE_ATTR_DATA], NULL, false))
 365                 return false;
 366
 367         if (!instance_fill_array(&in->netdev, tb[INSTANCE_ATTR_NETDEV], instance_netdev_update, true))
 368                 return false;
 369
 370         if (!instance_fill_array(&in->file, tb[INSTANCE_ATTR_FILE], instance_file_update, true))
 371                 return false;
 372
 373         return true;
 374 }
 375
 376 static void
 377 instance_config_cleanup(struct service_instance *in)
 378 {
 379         blobmsg_list_free(&in->env);
 380         blobmsg_list_free(&in->data);
 381         blobmsg_list_free(&in->netdev);
 382 }
 383
 384 static void
 385 instance_config_move(struct service_instance *in, struct service_instance *in_src)
 386 {
 387         instance_config_cleanup(in);
 388         blobmsg_list_move(&in->env, &in_src->env);
 389         blobmsg_list_move(&in->data, &in_src->data);
 390         blobmsg_list_move(&in->netdev, &in_src->netdev);
 391         in->trigger = in_src->trigger;
 392         in->command = in_src->command;
 393         in->name = in_src->name;
 394         in->node.avl.key = in_src->node.avl.key;
 395
 396         free(in->config);
 397         in->config = in_src->config;
 398         in_src->config = NULL;
 399 }
 400
 401 bool
 402 instance_update(struct service_instance *in, struct service_instance *in_new)
 403 {
 404         bool changed = instance_config_changed(in, in_new);
 405         bool running = in->proc.pending;
 406
 407         if (!changed && running)
 408                 return false;
 409
 410         if (!running) {
 411                 if (changed)
 412                         instance_config_move(in, in_new);
 413                 instance_start(in);
 414         } else {
 415                 instance_restart(in);
 416                 instance_config_move(in, in_new);
 417                 /* restart happens in the child callback handler */
 418         }
 419         return true;
 420 }
 421
 422 void
 423 instance_free(struct service_instance *in)
 424 {
 425         uloop_process_delete(&in->proc);
 426         uloop_timeout_cancel(&in->timeout);
 427         trigger_del(in);
 428         free(in->trigger);
 429         instance_config_cleanup(in);
 430         free(in->config);
 431         free(in);
 432 }
 433
 434 void
 435 instance_init(struct service_instance *in, struct service *s, struct blob_attr *config)
 436 {
 437         config = blob_memdup(config);
 438         in->srv = s;
 439         in->name = blobmsg_name(config);
 440         in->config = config;
 441         in->timeout.cb = instance_timeout;
 442         in->proc.cb = instance_exit;
 443
 444         blobmsg_list_init(&in->netdev, struct instance_netdev, node, instance_netdev_cmp);
 445         blobmsg_list_init(&in->file, struct instance_file, node, instance_file_cmp);
 446         blobmsg_list_simple_init(&in->env);
 447         blobmsg_list_simple_init(&in->data);
 448         in->valid = instance_config_parse(in);
 449 }
 450
 451 void instance_dump(struct blob_buf *b, struct service_instance *in, int verbose)
 452 {
 453         void *i;
 454
 455         i = blobmsg_open_table(b, in->name);
 456         blobmsg_add_u8(b, "running", in->proc.pending);
 457         if (in->proc.pending)
 458                 blobmsg_add_u32(b, "pid", in->proc.pid);
 459         blobmsg_add_blob(b, in->command);
 460
 461         if (!avl_is_empty(&in->env.avl)) {
 462                 struct blobmsg_list_node *var;
 463                 void *e = blobmsg_open_table(b, "env");
 464                 blobmsg_list_for_each(&in->env, var)
 465                         blobmsg_add_string(b, blobmsg_name(var->data), blobmsg_data(var->data));
 466                 blobmsg_close_table(b, e);
 467         }
 468
 469         if (in->respawn) {
 470                 void *r = blobmsg_open_table(b, "respawn");
 471                 blobmsg_add_u32(b, "timeout", in->respawn_timeout);
 472                 blobmsg_add_u32(b, "threshold", in->respawn_threshold);
 473                 blobmsg_add_u32(b, "retry", in->respawn_retry);
 474                 blobmsg_close_table(b, r);
 475         }
 476
 477         if (verbose && in->trigger)
 478                 blobmsg_add_blob(b, in->trigger);
 479
 480         blobmsg_close_table(b, i);
 481 }