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