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 #include "service.h"
  25 #include "instance.h"
  26 #include "md5.h"
  27
  28 enum {
  29         INSTANCE_ATTR_COMMAND,
  30         INSTANCE_ATTR_ENV,
  31         INSTANCE_ATTR_DATA,
  32         INSTANCE_ATTR_NETDEV,
  33         INSTANCE_ATTR_FILE,
  34         INSTANCE_ATTR_TRIGGER,
  35         INSTANCE_ATTR_RESPAWN,
  36         INSTANCE_ATTR_NICE,
  37         __INSTANCE_ATTR_MAX
  38 };
  39
  40 static const struct blobmsg_policy instance_attr[__INSTANCE_ATTR_MAX] = {
  41         [INSTANCE_ATTR_COMMAND] = { "command", BLOBMSG_TYPE_ARRAY },
  42         [INSTANCE_ATTR_ENV] = { "env", BLOBMSG_TYPE_TABLE },
  43         [INSTANCE_ATTR_DATA] = { "data", BLOBMSG_TYPE_TABLE },
  44         [INSTANCE_ATTR_NETDEV] = { "netdev", BLOBMSG_TYPE_ARRAY },
  45         [INSTANCE_ATTR_FILE] = { "file", BLOBMSG_TYPE_ARRAY },
  46         [INSTANCE_ATTR_TRIGGER] = { "triggers", BLOBMSG_TYPE_ARRAY },
  47         [INSTANCE_ATTR_RESPAWN] = { "respawn", BLOBMSG_TYPE_ARRAY },
  48         [INSTANCE_ATTR_NICE] = { "nice", BLOBMSG_TYPE_INT32 },
  49 };
  50
  51 struct instance_netdev {
  52         struct blobmsg_list_node node;
  53         int ifindex;
  54 };
  55
  56 struct instance_file {
  57         struct blobmsg_list_node node;
  58         uint32_t md5[4];
  59 };
  60
  61 static void
  62 instance_run(struct service_instance *in)
  63 {
  64         struct blobmsg_list_node *var;
  65         struct blob_attr *cur;
  66         char **argv;
  67         int argc = 1; /* NULL terminated */
  68         int rem, fd;
  69
  70         if (in->nice)
  71                 setpriority(PRIO_PROCESS, 0, in->nice);
  72
  73         blobmsg_for_each_attr(cur, in->command, rem)
  74                 argc++;
  75
  76         blobmsg_list_for_each(&in->env, var)
  77                 setenv(blobmsg_name(var->data), blobmsg_data(var->data), 1);
  78
  79         argv = alloca(sizeof(char *) * argc);
  80         argc = 0;
  81
  82         blobmsg_for_each_attr(cur, in->command, rem)
  83                 argv[argc++] = blobmsg_data(cur);
  84
  85         argv[argc] = NULL;
  86         fd = open("/dev/null", O_RDWR);
  87         if (fd > -1) {
  88                 dup2(fd, STDIN_FILENO);
  89                 dup2(fd, STDOUT_FILENO);
  90                 dup2(fd, STDERR_FILENO);
  91                 if (fd > STDERR_FILENO)
  92                         close(fd);
  93         }
  94         execvp(argv[0], argv);
  95         exit(127);
  96 }
  97
  98 void
  99 instance_start(struct service_instance *in)
 100 {
 101         int pid;
 102
 103         if (in->proc.pending)
 104                 return;
 105
 106         in->restart = false;
 107         in->halt = !in->respawn;
 108
 109         if (!in->valid)
 110                 return;
 111
 112         pid = fork();
 113         if (pid < 0)
 114                 return;
 115
 116         if (!pid) {
 117                 uloop_done();
 118                 instance_run(in);
 119                 return;
 120         }
 121
 122         DEBUG(1, "Started instance %s::%s\n", in->srv->name, in->name);
 123         in->proc.pid = pid;
 124         clock_gettime(CLOCK_MONOTONIC, &in->start);
 125         uloop_process_add(&in->proc);
 126 }
 127
 128 static void
 129 instance_timeout(struct uloop_timeout *t)
 130 {
 131         struct service_instance *in;
 132
 133         in = container_of(t, struct service_instance, timeout);
 134
 135         if (!in->halt && (in->restart || in->respawn))
 136                 instance_start(in);
 137 }
 138
 139 static void
 140 instance_exit(struct uloop_process *p, int ret)
 141 {
 142         struct service_instance *in;
 143         struct timespec tp;
 144         long runtime;
 145
 146         in = container_of(p, struct service_instance, proc);
 147
 148         clock_gettime(CLOCK_MONOTONIC, &tp);
 149         runtime = tp.tv_sec - in->start.tv_sec;
 150
 151         DEBUG(1, "Instance %s::%s exit with error code %d after %ld seconds\n", in->srv->name, in->name, ret, runtime);
 152         uloop_timeout_cancel(&in->timeout);
 153         if (in->halt) {
 154                 /* no action */
 155         } else if (in->restart) {
 156                 instance_start(in);
 157         } else if (in->respawn) {
 158                 if (runtime < RESPAWN_ERROR)
 159                         in->respawn_count++;
 160                 else
 161                         in->respawn_count = 0;
 162                 if (in->respawn_count > 5)
 163                         DEBUG(1, "Instance %s::%s s in a crash loop %d crashes, %ld seconds since last crash\n",
 164                                                                 in->srv->name, in->name, in->respawn_count, runtime);
 165                 uloop_timeout_set(&in->timeout, 5000);
 166         }
 167 }
 168
 169 void
 170 instance_stop(struct service_instance *in)
 171 {
 172         if (!in->proc.pending)
 173                 return;
 174         in->halt = true;
 175         in->restart = in->respawn = false;
 176         kill(in->proc.pid, SIGTERM);
 177 }
 178
 179 static void
 180 instance_restart(struct service_instance *in)
 181 {
 182         if (!in->proc.pending)
 183                 return;
 184         in->halt = false;
 185         in->restart = true;
 186         kill(in->proc.pid, SIGTERM);
 187 }
 188
 189 static bool
 190 instance_config_changed(struct service_instance *in, struct service_instance *in_new)
 191 {
 192         if (!in->valid)
 193                 return true;
 194
 195         if (!blob_attr_equal(in->command, in_new->command))
 196                 return true;
 197
 198         if (!blobmsg_list_equal(&in->env, &in_new->env))
 199                 return true;
 200
 201         if (!blobmsg_list_equal(&in->data, &in_new->data))
 202                 return true;
 203
 204         if (!blobmsg_list_equal(&in->netdev, &in_new->netdev))
 205                 return true;
 206
 207         if (!blobmsg_list_equal(&in->file, &in_new->file))
 208                 return true;
 209
 210         if (in->nice != in_new->nice)
 211                 return true;
 212
 213         return false;
 214 }
 215
 216 static bool
 217 instance_netdev_cmp(struct blobmsg_list_node *l1, struct blobmsg_list_node *l2)
 218 {
 219         struct instance_netdev *n1 = container_of(l1, struct instance_netdev, node);
 220         struct instance_netdev *n2 = container_of(l2, struct instance_netdev, node);
 221
 222         return n1->ifindex == n2->ifindex;
 223 }
 224
 225 static void
 226 instance_netdev_update(struct blobmsg_list_node *l)
 227 {
 228         struct instance_netdev *n = container_of(l, struct instance_netdev, node);
 229
 230         n->ifindex = if_nametoindex(n->node.avl.key);
 231 }
 232
 233 static bool
 234 instance_file_cmp(struct blobmsg_list_node *l1, struct blobmsg_list_node *l2)
 235 {
 236         struct instance_file *f1 = container_of(l1, struct instance_file, node);
 237         struct instance_file *f2 = container_of(l2, struct instance_file, node);
 238
 239         return !memcmp(f1->md5, f2->md5, sizeof(f1->md5));
 240 }
 241
 242 static void
 243 instance_file_update(struct blobmsg_list_node *l)
 244 {
 245         struct instance_file *f = container_of(l, struct instance_file, node);
 246         md5_ctx_t md5;
 247         char buf[256];
 248         int len, fd;
 249
 250         memset(f->md5, 0, sizeof(f->md5));
 251
 252         fd = open(l->avl.key, O_RDONLY);
 253         if (fd < 0)
 254                 return;
 255
 256         md5_begin(&md5);
 257         do {
 258                 len = read(fd, buf, sizeof(buf));
 259                 if (len < 0) {
 260                         if (errno == EINTR)
 261                                 continue;
 262
 263                         break;
 264                 }
 265                 if (!len)
 266                         break;
 267
 268                 md5_hash(buf, len, &md5);
 269         } while(1);
 270
 271         md5_end(f->md5, &md5);
 272         close(fd);
 273 }
 274
 275 static bool
 276 instance_fill_array(struct blobmsg_list *l, struct blob_attr *cur, blobmsg_update_cb cb, bool array)
 277 {
 278         struct blobmsg_list_node *node;
 279
 280         if (!cur)
 281                 return true;
 282
 283         if (!blobmsg_check_attr_list(cur, BLOBMSG_TYPE_STRING))
 284                 return false;
 285
 286         blobmsg_list_fill(l, blobmsg_data(cur), blobmsg_data_len(cur), array);
 287         if (cb) {
 288                 blobmsg_list_for_each(l, node)
 289                         cb(node);
 290         }
 291         return true;
 292 }
 293
 294 static bool
 295 instance_config_parse(struct service_instance *in)
 296 {
 297         struct blob_attr *tb[__INSTANCE_ATTR_MAX];
 298         struct blob_attr *cur, *cur2;
 299         int argc = 0;
 300         int rem;
 301
 302         blobmsg_parse(instance_attr, __INSTANCE_ATTR_MAX, tb,
 303                 blobmsg_data(in->config), blobmsg_data_len(in->config));
 304
 305         cur = tb[INSTANCE_ATTR_COMMAND];
 306         if (!cur)
 307                 return false;
 308
 309         if (!blobmsg_check_attr_list(cur, BLOBMSG_TYPE_STRING))
 310                 return false;
 311
 312         blobmsg_for_each_attr(cur2, cur, rem) {
 313                 argc++;
 314                 break;
 315         }
 316         if (!argc)
 317                 return false;
 318
 319         in->command = cur;
 320
 321         if (tb[INSTANCE_ATTR_TRIGGER]) {
 322                 in->trigger = malloc(blob_len(tb[INSTANCE_ATTR_TRIGGER]));
 323                 if (!in->trigger)
 324                         return -1;
 325                 memcpy(in->trigger, tb[INSTANCE_ATTR_TRIGGER], blob_len(tb[INSTANCE_ATTR_TRIGGER]));
 326                 trigger_add(in->trigger, in);
 327         }
 328
 329         if ((cur = tb[INSTANCE_ATTR_NICE])) {
 330                 in->nice = (int8_t) blobmsg_get_u32(cur);
 331                 if (in->nice < -20 || in->nice > 20)
 332                         return false;
 333         }
 334
 335         if (!instance_fill_array(&in->env, tb[INSTANCE_ATTR_ENV], NULL, false))
 336                 return false;
 337
 338         if (!instance_fill_array(&in->data, tb[INSTANCE_ATTR_DATA], NULL, false))
 339                 return false;
 340
 341         if (!instance_fill_array(&in->netdev, tb[INSTANCE_ATTR_NETDEV], instance_netdev_update, true))
 342                 return false;
 343
 344         if (!instance_fill_array(&in->file, tb[INSTANCE_ATTR_FILE], instance_file_update, true))
 345                 return false;
 346
 347         return true;
 348 }
 349
 350 static void
 351 instance_config_cleanup(struct service_instance *in)
 352 {
 353         blobmsg_list_free(&in->env);
 354         blobmsg_list_free(&in->data);
 355         blobmsg_list_free(&in->netdev);
 356 }
 357
 358 static void
 359 instance_config_move(struct service_instance *in, struct service_instance *in_src)
 360 {
 361         instance_config_cleanup(in);
 362         blobmsg_list_move(&in->env, &in_src->env);
 363         blobmsg_list_move(&in->data, &in_src->data);
 364         blobmsg_list_move(&in->netdev, &in_src->netdev);
 365         in->trigger = in_src->trigger;
 366         in->command = in_src->command;
 367         in->name = in_src->name;
 368         in->node.avl.key = in_src->node.avl.key;
 369
 370         free(in->config);
 371         in->config = in_src->config;
 372         in_src->config = NULL;
 373 }
 374
 375 bool
 376 instance_update(struct service_instance *in, struct service_instance *in_new)
 377 {
 378         bool changed = instance_config_changed(in, in_new);
 379         bool running = in->proc.pending;
 380
 381         if (!changed && running)
 382                 return false;
 383
 384         if (!running) {
 385                 if (changed)
 386                         instance_config_move(in, in_new);
 387                 instance_start(in);
 388         } else {
 389                 instance_restart(in);
 390                 instance_config_move(in, in_new);
 391                 /* restart happens in the child callback handler */
 392         }
 393         return true;
 394 }
 395
 396 void
 397 instance_free(struct service_instance *in)
 398 {
 399         uloop_process_delete(&in->proc);
 400         uloop_timeout_cancel(&in->timeout);
 401         trigger_del(in);
 402         free(in->trigger);
 403         instance_config_cleanup(in);
 404         free(in->config);
 405         free(in);
 406 }
 407
 408 void
 409 instance_init(struct service_instance *in, struct service *s, struct blob_attr *config)
 410 {
 411         config = blob_memdup(config);
 412         in->srv = s;
 413         in->name = blobmsg_name(config);
 414         in->config = config;
 415         in->timeout.cb = instance_timeout;
 416         in->proc.cb = instance_exit;
 417         in->respawn = true;
 418         in->respawn_count = 0;
 419
 420         blobmsg_list_init(&in->netdev, struct instance_netdev, node, instance_netdev_cmp);
 421         blobmsg_list_init(&in->file, struct instance_file, node, instance_file_cmp);
 422         blobmsg_list_simple_init(&in->env);
 423         blobmsg_list_simple_init(&in->data);
 424         in->valid = instance_config_parse(in);
 425 }
 426
 427 void instance_dump(struct blob_buf *b, struct service_instance *in, int verbose)
 428 {
 429         void *i;
 430         struct pid_info pi;
 431
 432         i = blobmsg_open_table(b, in->name);
 433         blobmsg_add_u8(b, "running", in->proc.pending);
 434         if (in->proc.pending)
 435                 blobmsg_add_u32(b, "pid", in->proc.pid);
 436         blobmsg_add_blob(b, in->command);
 437         if (verbose && in->trigger)
 438                 blobmsg_add_blob(b, in->trigger);
 439         if (!measure_process(in->proc.pid, &pi)) {
 440                 struct timespec tp;
 441                 long uptime;
 442
 443                 clock_gettime(CLOCK_MONOTONIC, &tp);
 444                 uptime = tp.tv_sec - in->start.tv_sec;
 445
 446                 blobmsg_add_u8(b, "ppid", pi.ppid);
 447                 blobmsg_add_u16(b, "uid", pi.uid);
 448                 blobmsg_add_u32(b, "fdcount", pi.fdcount);
 449                 blobmsg_add_u32(b, "vmsize", pi.vmsize);
 450                 blobmsg_add_u32(b, "uptime", uptime);
 451         }
 452         blobmsg_close_table(b, i);
 453 }