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