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