instance.c

   1 #include <sys/resource.h>
   2 #include <sys/types.h>
   3 #include <sys/socket.h>
   4 #include <net/if.h>
   5 #include <unistd.h>
   6 #include <stdint.h>
   7 #include <fcntl.h>
   8
   9 #include "procd.h"
  10 #include "service.h"
  11 #include "instance.h"
  12 #include "md5.h"
  13
  14 enum {
  15         INSTANCE_ATTR_COMMAND,
  16         INSTANCE_ATTR_ENV,
  17         INSTANCE_ATTR_DATA,
  18         INSTANCE_ATTR_NETDEV,
  19         INSTANCE_ATTR_FILE,
  20         INSTANCE_ATTR_NICE,
  21         __INSTANCE_ATTR_MAX
  22 };
  23
  24 static const struct blobmsg_policy instance_attr[__INSTANCE_ATTR_MAX] = {
  25         [INSTANCE_ATTR_COMMAND] = { "command", BLOBMSG_TYPE_ARRAY },
  26         [INSTANCE_ATTR_ENV] = { "env", BLOBMSG_TYPE_TABLE },
  27         [INSTANCE_ATTR_DATA] = { "data", BLOBMSG_TYPE_TABLE },
  28         [INSTANCE_ATTR_NETDEV] = { "netdev", BLOBMSG_TYPE_ARRAY },
  29         [INSTANCE_ATTR_FILE] = { "file", BLOBMSG_TYPE_ARRAY },
  30         [INSTANCE_ATTR_NICE] = { "nice", BLOBMSG_TYPE_INT32 },
  31 };
  32
  33 struct instance_netdev {
  34         struct blobmsg_list_node node;
  35         int ifindex;
  36 };
  37
  38 struct instance_file {
  39         struct blobmsg_list_node node;
  40         uint32_t md5[4];
  41 };
  42
  43 static void
  44 instance_run(struct service_instance *in)
  45 {
  46         struct blobmsg_list_node *var;
  47         struct blob_attr *cur;
  48         char **argv;
  49         int argc = 1; /* NULL terminated */
  50         int rem;
  51
  52         if (in->nice)
  53                 setpriority(PRIO_PROCESS, 0, in->nice);
  54
  55         blobmsg_for_each_attr(cur, in->command, rem)
  56                 argc++;
  57
  58         blobmsg_list_for_each(&in->env, var)
  59                 setenv(blobmsg_name(var->data), blobmsg_data(var->data), 1);
  60
  61         argv = alloca(sizeof(char *) * argc);
  62         argc = 0;
  63
  64         blobmsg_for_each_attr(cur, in->command, rem)
  65                 argv[argc++] = blobmsg_data(cur);
  66
  67         argv[argc] = NULL;
  68         execvp(argv[0], argv);
  69         exit(127);
  70 }
  71
  72 void
  73 instance_start(struct service_instance *in)
  74 {
  75         int pid;
  76
  77         if (in->proc.pending)
  78                 return;
  79
  80         in->restart = false;
  81         if (!in->valid)
  82                 return;
  83
  84         pid = fork();
  85         if (pid < 0)
  86                 return;
  87
  88         if (!pid) {
  89                 instance_run(in);
  90                 return;
  91         }
  92
  93         DPRINTF("Started instance %s::%s\n", in->srv->name, in->name);
  94         in->proc.pid = pid;
  95         uloop_process_add(&in->proc);
  96 }
  97
  98 static void
  99 instance_timeout(struct uloop_timeout *t)
 100 {
 101         struct service_instance *in;
 102
 103         in = container_of(t, struct service_instance, timeout);
 104         kill(in->proc.pid, SIGKILL);
 105         uloop_process_delete(&in->proc);
 106         in->proc.cb(&in->proc, -1);
 107 }
 108
 109 static void
 110 instance_exit(struct uloop_process *p, int ret)
 111 {
 112         struct service_instance *in;
 113
 114         in = container_of(p, struct service_instance, proc);
 115         DPRINTF("Instance %s::%s exit with error code %d\n", in->srv->name, in->name, ret);
 116         uloop_timeout_cancel(&in->timeout);
 117         if (in->restart)
 118                 instance_start(in);
 119 }
 120
 121 void
 122 instance_stop(struct service_instance *in, bool restart)
 123 {
 124         if (!in->proc.pending)
 125                 return;
 126
 127         kill(in->proc.pid, SIGTERM);
 128 }
 129
 130 static bool
 131 instance_config_changed(struct service_instance *in, struct service_instance *in_new)
 132 {
 133         if (!in->valid)
 134                 return true;
 135
 136         if (!blob_attr_equal(in->command, in_new->command))
 137                 return true;
 138
 139         if (!blobmsg_list_equal(&in->env, &in_new->env))
 140                 return true;
 141
 142         if (!blobmsg_list_equal(&in->data, &in_new->data))
 143                 return true;
 144
 145         if (!blobmsg_list_equal(&in->netdev, &in_new->netdev))
 146                 return true;
 147
 148         if (!blobmsg_list_equal(&in->file, &in_new->file))
 149                 return true;
 150
 151         if (in->nice != in_new->nice)
 152                 return true;
 153
 154         return false;
 155 }
 156
 157 static bool
 158 instance_netdev_cmp(struct blobmsg_list_node *l1, struct blobmsg_list_node *l2)
 159 {
 160         struct instance_netdev *n1 = container_of(l1, struct instance_netdev, node);
 161         struct instance_netdev *n2 = container_of(l2, struct instance_netdev, node);
 162
 163         return n1->ifindex == n2->ifindex;
 164 }
 165
 166 static void
 167 instance_netdev_update(struct blobmsg_list_node *l)
 168 {
 169         struct instance_netdev *n = container_of(l, struct instance_netdev, node);
 170
 171         n->ifindex = if_nametoindex(n->node.avl.key);
 172 }
 173
 174 static bool
 175 instance_file_cmp(struct blobmsg_list_node *l1, struct blobmsg_list_node *l2)
 176 {
 177         struct instance_file *f1 = container_of(l1, struct instance_file, node);
 178         struct instance_file *f2 = container_of(l2, struct instance_file, node);
 179
 180         return !memcmp(f1->md5, f2->md5, sizeof(f1->md5));
 181 }
 182
 183 static void
 184 instance_file_update(struct blobmsg_list_node *l)
 185 {
 186         struct instance_file *f = container_of(l, struct instance_file, node);
 187         md5_ctx_t md5;
 188         char buf[256];
 189         int len, fd;
 190
 191         memset(f->md5, 0, sizeof(f->md5));
 192
 193         fd = open(l->avl.key, O_RDONLY);
 194         if (fd < 0)
 195                 return;
 196
 197         md5_begin(&md5);
 198         do {
 199                 len = read(fd, buf, sizeof(buf));
 200                 if (len < 0) {
 201                         if (errno == EINTR)
 202                                 continue;
 203
 204                         break;
 205                 }
 206                 if (!len)
 207                         break;
 208
 209                 md5_hash(buf, len, &md5);
 210         } while(1);
 211
 212         md5_end(f->md5, &md5);
 213         close(fd);
 214 }
 215
 216 static bool
 217 instance_fill_array(struct blobmsg_list *l, struct blob_attr *cur, blobmsg_update_cb cb, bool array)
 218 {
 219         struct blobmsg_list_node *node;
 220
 221         if (!cur)
 222                 return true;
 223
 224         if (!blobmsg_check_attr_list(cur, BLOBMSG_TYPE_STRING))
 225                 return false;
 226
 227         blobmsg_list_fill(l, blobmsg_data(cur), blobmsg_data_len(cur), array);
 228         if (cb) {
 229                 blobmsg_list_for_each(l, node)
 230                         cb(node);
 231         }
 232         return true;
 233 }
 234
 235 static bool
 236 instance_config_parse(struct service_instance *in)
 237 {
 238         struct blob_attr *tb[__INSTANCE_ATTR_MAX];
 239         struct blob_attr *cur, *cur2;
 240         int argc = 0;
 241         int rem;
 242
 243         blobmsg_parse(instance_attr, __INSTANCE_ATTR_MAX, tb,
 244                 blobmsg_data(in->config), blobmsg_data_len(in->config));
 245
 246         cur = tb[INSTANCE_ATTR_COMMAND];
 247         if (!cur)
 248                 return false;
 249
 250         if (!blobmsg_check_attr_list(cur, BLOBMSG_TYPE_STRING))
 251                 return false;
 252
 253         blobmsg_for_each_attr(cur2, cur, rem) {
 254                 argc++;
 255                 break;
 256         }
 257         if (!argc)
 258                 return false;
 259
 260         in->command = cur;
 261
 262         if ((cur = tb[INSTANCE_ATTR_NICE])) {
 263                 in->nice = (int8_t) blobmsg_get_u32(cur);
 264                 if (in->nice < -20 || in->nice > 20)
 265                         return false;
 266         }
 267
 268         if (!instance_fill_array(&in->env, tb[INSTANCE_ATTR_ENV], NULL, false))
 269                 return false;
 270
 271         if (!instance_fill_array(&in->data, tb[INSTANCE_ATTR_DATA], NULL, false))
 272                 return false;
 273
 274         if (!instance_fill_array(&in->netdev, tb[INSTANCE_ATTR_NETDEV], instance_netdev_update, true))
 275                 return false;
 276
 277         if (!instance_fill_array(&in->file, tb[INSTANCE_ATTR_FILE], instance_file_update, true))
 278                 return false;
 279
 280         return true;
 281 }
 282
 283 static void
 284 instance_config_cleanup(struct service_instance *in)
 285 {
 286         blobmsg_list_free(&in->env);
 287         blobmsg_list_free(&in->data);
 288         blobmsg_list_free(&in->netdev);
 289 }
 290
 291 static void
 292 instance_config_move(struct service_instance *in, struct service_instance *in_src)
 293 {
 294         instance_config_cleanup(in);
 295         blobmsg_list_move(&in->env, &in_src->env);
 296         blobmsg_list_move(&in->data, &in_src->data);
 297         blobmsg_list_move(&in->netdev, &in_src->netdev);
 298         in->command = in_src->command;
 299         in->name = in_src->name;
 300         in->node.avl.key = in_src->node.avl.key;
 301
 302         free(in->config);
 303         in->config = in_src->config;
 304         in_src->config = NULL;
 305 }
 306
 307 bool
 308 instance_update(struct service_instance *in, struct service_instance *in_new)
 309 {
 310         bool changed = instance_config_changed(in, in_new);
 311
 312         if (!changed)
 313                 return false;
 314
 315         in->restart = true;
 316         instance_stop(in, true);
 317         instance_config_move(in, in_new);
 318         return true;
 319 }
 320
 321 void
 322 instance_free(struct service_instance *in)
 323 {
 324         uloop_process_delete(&in->proc);
 325         uloop_timeout_cancel(&in->timeout);
 326         instance_config_cleanup(in);
 327         free(in->config);
 328         free(in);
 329 }
 330
 331 void
 332 instance_init(struct service_instance *in, struct service *s, struct blob_attr *config)
 333 {
 334         config = blob_memdup(config);
 335         in->srv = s;
 336         in->name = blobmsg_name(config);
 337         in->config = config;
 338         in->timeout.cb = instance_timeout;
 339         in->proc.cb = instance_exit;
 340
 341         blobmsg_list_init(&in->netdev, struct instance_netdev, node, instance_netdev_cmp);
 342         blobmsg_list_init(&in->file, struct instance_file, node, instance_file_cmp);
 343         blobmsg_list_simple_init(&in->env);
 344         blobmsg_list_simple_init(&in->data);
 345         in->valid = instance_config_parse(in);
 346 }
 347
 348 void instance_dump(struct blob_buf *b, struct service_instance *in)
 349 {
 350         void *i;
 351
 352         i = blobmsg_open_table(b, in->name);
 353         blobmsg_add_u8(b, "running", in->proc.pending);
 354         if (in->proc.pending)
 355                 blobmsg_add_u32(b, "pid", in->proc.pid);
 356         blobmsg_add_blob(b, in->command);
 357         blobmsg_close_table(b, i);
 358 }