ubusd_proto.c

   1 /*
   2  * Copyright (C) 2011-2014 Felix Fietkau <nbd@openwrt.org>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU Lesser General Public License version 2.1
   6  * as published by the Free Software Foundation
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include <arpa/inet.h>
  15 #include <unistd.h>
  16
  17 #include "ubusd.h"
  18
  19 struct blob_buf b;
  20 static struct ubus_msg_buf *retmsg;
  21 static int *retmsg_data;
  22 static struct avl_tree clients;
  23
  24 static struct blob_attr *attrbuf[UBUS_ATTR_MAX];
  25
  26 typedef int (*ubus_cmd_cb)(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr);
  27
  28 static const struct blob_attr_info ubus_policy[UBUS_ATTR_MAX] = {
  29         [UBUS_ATTR_SIGNATURE] = { .type = BLOB_ATTR_NESTED },
  30         [UBUS_ATTR_OBJTYPE] = { .type = BLOB_ATTR_INT32 },
  31         [UBUS_ATTR_OBJPATH] = { .type = BLOB_ATTR_STRING },
  32         [UBUS_ATTR_OBJID] = { .type = BLOB_ATTR_INT32 },
  33         [UBUS_ATTR_STATUS] = { .type = BLOB_ATTR_INT32 },
  34         [UBUS_ATTR_METHOD] = { .type = BLOB_ATTR_STRING },
  35         [UBUS_ATTR_USER] = { .type = BLOB_ATTR_STRING },
  36         [UBUS_ATTR_GROUP] = { .type = BLOB_ATTR_STRING },
  37 };
  38
  39 struct blob_attr **ubus_parse_msg(struct blob_attr *msg)
  40 {
  41         blob_parse(msg, attrbuf, ubus_policy, UBUS_ATTR_MAX);
  42         return attrbuf;
  43 }
  44
  45 static void ubus_msg_close_fd(struct ubus_msg_buf *ub)
  46 {
  47         if (ub->fd < 0)
  48                 return;
  49
  50         close(ub->fd);
  51         ub->fd = -1;
  52 }
  53
  54 static void ubus_msg_init(struct ubus_msg_buf *ub, uint8_t type, uint16_t seq, uint32_t peer)
  55 {
  56         ub->hdr.version = 0;
  57         ub->hdr.type = type;
  58         ub->hdr.seq = seq;
  59         ub->hdr.peer = peer;
  60 }
  61
  62 static struct ubus_msg_buf *ubus_msg_from_blob(bool shared)
  63 {
  64         return ubus_msg_new(b.head, blob_raw_len(b.head), shared);
  65 }
  66
  67 static struct ubus_msg_buf *ubus_reply_from_blob(struct ubus_msg_buf *ub, bool shared)
  68 {
  69         struct ubus_msg_buf *new;
  70
  71         new = ubus_msg_from_blob(shared);
  72         if (!new)
  73                 return NULL;
  74
  75         ubus_msg_init(new, UBUS_MSG_DATA, ub->hdr.seq, ub->hdr.peer);
  76         return new;
  77 }
  78
  79 void
  80 ubus_proto_send_msg_from_blob(struct ubus_client *cl, struct ubus_msg_buf *ub,
  81                         uint8_t type)
  82 {
  83         ub = ubus_reply_from_blob(ub, true);
  84         if (!ub)
  85                 return;
  86
  87         ub->hdr.type = type;
  88         ubus_msg_send(cl, ub, true);
  89 }
  90
  91 static bool ubusd_send_hello(struct ubus_client *cl)
  92 {
  93         struct ubus_msg_buf *ub;
  94
  95         blob_buf_init(&b, 0);
  96         ub = ubus_msg_from_blob(true);
  97         if (!ub)
  98                 return false;
  99
 100         ubus_msg_init(ub, UBUS_MSG_HELLO, 0, cl->id.id);
 101         ubus_msg_send(cl, ub, true);
 102         return true;
 103 }
 104
 105 static int ubusd_send_pong(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 106 {
 107         ub->hdr.type = UBUS_MSG_DATA;
 108         ubus_msg_send(cl, ub, false);
 109         return 0;
 110 }
 111
 112 static int ubusd_handle_remove_object(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 113 {
 114         struct ubus_object *obj;
 115
 116         if (!attr[UBUS_ATTR_OBJID])
 117                 return UBUS_STATUS_INVALID_ARGUMENT;
 118
 119         obj = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_OBJID]));
 120         if (!obj)
 121                 return UBUS_STATUS_NOT_FOUND;
 122
 123         if (obj->client != cl)
 124                 return UBUS_STATUS_PERMISSION_DENIED;
 125
 126         blob_buf_init(&b, 0);
 127         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
 128
 129         /* check if we're removing the object type as well */
 130         if (obj->type && obj->type->refcount == 1)
 131                 blob_put_int32(&b, UBUS_ATTR_OBJTYPE, obj->type->id.id);
 132
 133         ubusd_free_object(obj);
 134         ubus_proto_send_msg_from_blob(cl, ub, UBUS_MSG_DATA);
 135
 136         return 0;
 137 }
 138
 139 static int ubusd_handle_add_object(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 140 {
 141         struct ubus_object *obj;
 142
 143         obj = ubusd_create_object(cl, attr);
 144         if (!obj)
 145                 return UBUS_STATUS_INVALID_ARGUMENT;
 146
 147         blob_buf_init(&b, 0);
 148         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
 149         if (attr[UBUS_ATTR_SIGNATURE])
 150                 blob_put_int32(&b, UBUS_ATTR_OBJTYPE, obj->type->id.id);
 151
 152         ubus_proto_send_msg_from_blob(cl, ub, UBUS_MSG_DATA);
 153         return 0;
 154 }
 155
 156 static void ubusd_send_obj(struct ubus_client *cl, struct ubus_msg_buf *ub, struct ubus_object *obj)
 157 {
 158         struct ubus_method *m;
 159         int cnt = 0;
 160         void *s;
 161
 162         blob_buf_init(&b, 0);
 163
 164         blob_put_string(&b, UBUS_ATTR_OBJPATH, obj->path.key);
 165         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
 166         blob_put_int32(&b, UBUS_ATTR_OBJTYPE, obj->type->id.id);
 167
 168         s = blob_nest_start(&b, UBUS_ATTR_SIGNATURE);
 169         list_for_each_entry(m, &obj->type->methods, list) {
 170                 if (!ubusd_acl_check(cl, obj->path.key, blobmsg_name(m->data), UBUS_ACL_ACCESS)) {
 171                         blobmsg_add_blob(&b, m->data);
 172                         cnt++;
 173                 }
 174         }
 175         blob_nest_end(&b, s);
 176
 177         if (cnt)
 178                 ubus_proto_send_msg_from_blob(cl, ub, UBUS_MSG_DATA);
 179 }
 180
 181 static int ubusd_handle_lookup(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 182 {
 183         struct ubus_object *obj;
 184         char *objpath;
 185         bool found = false;
 186         int len;
 187
 188         if (!attr[UBUS_ATTR_OBJPATH]) {
 189                 avl_for_each_element(&path, obj, path)
 190                         ubusd_send_obj(cl, ub, obj);
 191                 return 0;
 192         }
 193
 194         objpath = blob_data(attr[UBUS_ATTR_OBJPATH]);
 195         len = strlen(objpath);
 196         if (objpath[len - 1] != '*') {
 197                 obj = avl_find_element(&path, objpath, obj, path);
 198                 if (!obj)
 199                         return UBUS_STATUS_NOT_FOUND;
 200
 201                 ubusd_send_obj(cl, ub, obj);
 202                 return 0;
 203         }
 204
 205         objpath[--len] = 0;
 206
 207         obj = avl_find_ge_element(&path, objpath, obj, path);
 208         if (!obj)
 209                 return UBUS_STATUS_NOT_FOUND;
 210
 211         while (!strncmp(objpath, obj->path.key, len)) {
 212                 found = true;
 213                 ubusd_send_obj(cl, ub, obj);
 214                 if (obj == avl_last_element(&path, obj, path))
 215                         break;
 216                 obj = avl_next_element(obj, path);
 217         }
 218
 219         if (!found)
 220                 return UBUS_STATUS_NOT_FOUND;
 221
 222         return 0;
 223 }
 224
 225 static void
 226 ubusd_forward_invoke(struct ubus_client *cl, struct ubus_object *obj,
 227                      const char *method, struct ubus_msg_buf *ub,
 228                      struct blob_attr *data)
 229 {
 230         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
 231         blob_put_string(&b, UBUS_ATTR_METHOD, method);
 232         if (cl->user)
 233                 blob_put_string(&b, UBUS_ATTR_USER, cl->user);
 234         if (cl->group)
 235                 blob_put_string(&b, UBUS_ATTR_GROUP, cl->group);
 236         if (data)
 237                 blob_put(&b, UBUS_ATTR_DATA, blob_data(data), blob_len(data));
 238
 239         ubus_proto_send_msg_from_blob(obj->client, ub, UBUS_MSG_INVOKE);
 240 }
 241
 242 static int ubusd_handle_invoke(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 243 {
 244         struct ubus_object *obj = NULL;
 245         struct ubus_id *id;
 246         const char *method;
 247
 248         if (!attr[UBUS_ATTR_METHOD] || !attr[UBUS_ATTR_OBJID])
 249                 return UBUS_STATUS_INVALID_ARGUMENT;
 250
 251         id = ubus_find_id(&objects, blob_get_u32(attr[UBUS_ATTR_OBJID]));
 252         if (!id)
 253                 return UBUS_STATUS_NOT_FOUND;
 254
 255         obj = container_of(id, struct ubus_object, id);
 256
 257         method = blob_data(attr[UBUS_ATTR_METHOD]);
 258
 259         if (ubusd_acl_check(cl, obj->path.key, method, UBUS_ACL_ACCESS))
 260                 return UBUS_STATUS_PERMISSION_DENIED;
 261
 262         if (!obj->client)
 263                 return obj->recv_msg(cl, ub, method, attr[UBUS_ATTR_DATA]);
 264
 265         ub->hdr.peer = cl->id.id;
 266         blob_buf_init(&b, 0);
 267
 268         ubusd_forward_invoke(cl, obj, method, ub, attr[UBUS_ATTR_DATA]);
 269         ubus_msg_free(ub);
 270
 271         return -1;
 272 }
 273
 274 static int ubusd_handle_notify(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 275 {
 276         struct ubus_object *obj = NULL;
 277         struct ubus_subscription *s;
 278         struct ubus_id *id;
 279         const char *method;
 280         bool no_reply = false;
 281         void *c;
 282
 283         if (!attr[UBUS_ATTR_METHOD] || !attr[UBUS_ATTR_OBJID])
 284                 return UBUS_STATUS_INVALID_ARGUMENT;
 285
 286         if (attr[UBUS_ATTR_NO_REPLY])
 287                 no_reply = blob_get_int8(attr[UBUS_ATTR_NO_REPLY]);
 288
 289         id = ubus_find_id(&objects, blob_get_u32(attr[UBUS_ATTR_OBJID]));
 290         if (!id)
 291                 return UBUS_STATUS_NOT_FOUND;
 292
 293         obj = container_of(id, struct ubus_object, id);
 294         if (obj->client != cl)
 295                 return UBUS_STATUS_PERMISSION_DENIED;
 296
 297         if (!no_reply) {
 298                 blob_buf_init(&b, 0);
 299                 blob_put_int32(&b, UBUS_ATTR_OBJID, id->id);
 300                 c = blob_nest_start(&b, UBUS_ATTR_SUBSCRIBERS);
 301                 list_for_each_entry(s, &obj->subscribers, list) {
 302                         blob_put_int32(&b, 0, s->subscriber->id.id);
 303                 }
 304                 blob_nest_end(&b, c);
 305                 blob_put_int32(&b, UBUS_ATTR_STATUS, 0);
 306                 ubus_proto_send_msg_from_blob(cl, ub, UBUS_MSG_STATUS);
 307         }
 308
 309         ub->hdr.peer = cl->id.id;
 310         method = blob_data(attr[UBUS_ATTR_METHOD]);
 311         list_for_each_entry(s, &obj->subscribers, list) {
 312                 blob_buf_init(&b, 0);
 313                 if (no_reply)
 314                         blob_put_int8(&b, UBUS_ATTR_NO_REPLY, 1);
 315                 ubusd_forward_invoke(cl, s->subscriber, method, ub, attr[UBUS_ATTR_DATA]);
 316         }
 317         ubus_msg_free(ub);
 318
 319         return -1;
 320 }
 321
 322 static struct ubus_client *ubusd_get_client_by_id(uint32_t id)
 323 {
 324         struct ubus_id *clid;
 325
 326         clid = ubus_find_id(&clients, id);
 327         if (!clid)
 328                 return NULL;
 329
 330         return container_of(clid, struct ubus_client, id);
 331 }
 332
 333 static int ubusd_handle_response(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 334 {
 335         struct ubus_object *obj;
 336
 337         if (!attr[UBUS_ATTR_OBJID] ||
 338             (ub->hdr.type == UBUS_MSG_STATUS && !attr[UBUS_ATTR_STATUS]) ||
 339             (ub->hdr.type == UBUS_MSG_DATA && !attr[UBUS_ATTR_DATA]))
 340                 goto error;
 341
 342         obj = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_OBJID]));
 343         if (!obj)
 344                 goto error;
 345
 346         if (cl != obj->client)
 347                 goto error;
 348
 349         cl = ubusd_get_client_by_id(ub->hdr.peer);
 350         if (!cl)
 351                 goto error;
 352
 353         ub->hdr.peer = blob_get_u32(attr[UBUS_ATTR_OBJID]);
 354         ubus_msg_send(cl, ub, true);
 355         return -1;
 356
 357 error:
 358         ubus_msg_free(ub);
 359         return -1;
 360 }
 361
 362 static int ubusd_handle_add_watch(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 363 {
 364         struct ubus_object *obj, *target;
 365
 366         if (!attr[UBUS_ATTR_OBJID] || !attr[UBUS_ATTR_TARGET])
 367                 return UBUS_STATUS_INVALID_ARGUMENT;
 368
 369         obj = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_OBJID]));
 370         if (!obj)
 371                 return UBUS_STATUS_NOT_FOUND;
 372
 373         if (cl != obj->client)
 374                 return UBUS_STATUS_INVALID_ARGUMENT;
 375
 376         target = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_TARGET]));
 377         if (!target)
 378                 return UBUS_STATUS_NOT_FOUND;
 379
 380         if (cl == target->client)
 381                 return UBUS_STATUS_INVALID_ARGUMENT;
 382
 383         if (!target->path.key) {
 384                 if (strcmp(target->client->user, cl->user) && strcmp(target->client->group, cl->group))
 385                         return UBUS_STATUS_NOT_FOUND;
 386         } else if (ubusd_acl_check(cl, target->path.key, NULL, UBUS_ACL_SUBSCRIBE)) {
 387                 return UBUS_STATUS_NOT_FOUND;
 388         }
 389
 390         ubus_subscribe(obj, target);
 391         return 0;
 392 }
 393
 394 static int ubusd_handle_remove_watch(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 395 {
 396         struct ubus_object *obj;
 397         struct ubus_subscription *s;
 398         uint32_t id;
 399
 400         if (!attr[UBUS_ATTR_OBJID] || !attr[UBUS_ATTR_TARGET])
 401                 return UBUS_STATUS_INVALID_ARGUMENT;
 402
 403         obj = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_OBJID]));
 404         if (!obj)
 405                 return UBUS_STATUS_NOT_FOUND;
 406
 407         if (cl != obj->client)
 408                 return UBUS_STATUS_INVALID_ARGUMENT;
 409
 410         id = blob_get_u32(attr[UBUS_ATTR_TARGET]);
 411         list_for_each_entry(s, &obj->target_list, target_list) {
 412                 if (s->target->id.id != id)
 413                         continue;
 414
 415                 ubus_unsubscribe(s);
 416                 return 0;
 417         }
 418
 419         return UBUS_STATUS_NOT_FOUND;
 420 }
 421
 422 static const ubus_cmd_cb handlers[__UBUS_MSG_LAST] = {
 423         [UBUS_MSG_PING] = ubusd_send_pong,
 424         [UBUS_MSG_ADD_OBJECT] = ubusd_handle_add_object,
 425         [UBUS_MSG_REMOVE_OBJECT] = ubusd_handle_remove_object,
 426         [UBUS_MSG_LOOKUP] = ubusd_handle_lookup,
 427         [UBUS_MSG_INVOKE] = ubusd_handle_invoke,
 428         [UBUS_MSG_STATUS] = ubusd_handle_response,
 429         [UBUS_MSG_DATA] = ubusd_handle_response,
 430         [UBUS_MSG_SUBSCRIBE] = ubusd_handle_add_watch,
 431         [UBUS_MSG_UNSUBSCRIBE] = ubusd_handle_remove_watch,
 432         [UBUS_MSG_NOTIFY] = ubusd_handle_notify,
 433 };
 434
 435 void ubusd_proto_receive_message(struct ubus_client *cl, struct ubus_msg_buf *ub)
 436 {
 437         ubus_cmd_cb cb = NULL;
 438         int ret;
 439
 440         retmsg->hdr.seq = ub->hdr.seq;
 441         retmsg->hdr.peer = ub->hdr.peer;
 442
 443         if (ub->hdr.type < __UBUS_MSG_LAST)
 444                 cb = handlers[ub->hdr.type];
 445
 446         if (ub->hdr.type != UBUS_MSG_STATUS)
 447                 ubus_msg_close_fd(ub);
 448
 449         if (cb)
 450                 ret = cb(cl, ub, ubus_parse_msg(ub->data));
 451         else
 452                 ret = UBUS_STATUS_INVALID_COMMAND;
 453
 454         if (ret == -1)
 455                 return;
 456
 457         ubus_msg_free(ub);
 458
 459         *retmsg_data = htonl(ret);
 460         ubus_msg_send(cl, retmsg, false);
 461 }
 462
 463 struct ubus_client *ubusd_proto_new_client(int fd, uloop_fd_handler cb)
 464 {
 465         struct ubus_client *cl;
 466
 467         cl = calloc(1, sizeof(*cl));
 468         if (!cl)
 469                 return NULL;
 470
 471         if (ubusd_acl_init_client(cl, fd))
 472                 goto free;
 473
 474         INIT_LIST_HEAD(&cl->objects);
 475         cl->sock.fd = fd;
 476         cl->sock.cb = cb;
 477         cl->pending_msg_fd = -1;
 478
 479         if (!ubus_alloc_id(&clients, &cl->id, 0))
 480                 goto free;
 481
 482         if (!ubusd_send_hello(cl))
 483                 goto delete;
 484
 485         return cl;
 486
 487 delete:
 488         ubus_free_id(&clients, &cl->id);
 489 free:
 490         free(cl);
 491         return NULL;
 492 }
 493
 494 void ubusd_proto_free_client(struct ubus_client *cl)
 495 {
 496         struct ubus_object *obj;
 497
 498         while (!list_empty(&cl->objects)) {
 499                 obj = list_first_entry(&cl->objects, struct ubus_object, list);
 500                 ubusd_free_object(obj);
 501         }
 502
 503         ubusd_acl_free_client(cl);
 504         ubus_free_id(&clients, &cl->id);
 505 }
 506
 507 void ubus_notify_subscription(struct ubus_object *obj)
 508 {
 509         bool active = !list_empty(&obj->subscribers);
 510         struct ubus_msg_buf *ub;
 511
 512         blob_buf_init(&b, 0);
 513         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
 514         blob_put_int8(&b, UBUS_ATTR_ACTIVE, active);
 515
 516         ub = ubus_msg_from_blob(false);
 517         if (!ub)
 518                 return;
 519
 520         ubus_msg_init(ub, UBUS_MSG_NOTIFY, ++obj->invoke_seq, 0);
 521         ubus_msg_send(obj->client, ub, true);
 522 }
 523
 524 void ubus_notify_unsubscribe(struct ubus_subscription *s)
 525 {
 526         struct ubus_msg_buf *ub;
 527
 528         blob_buf_init(&b, 0);
 529         blob_put_int32(&b, UBUS_ATTR_OBJID, s->subscriber->id.id);
 530         blob_put_int32(&b, UBUS_ATTR_TARGET, s->target->id.id);
 531
 532         ub = ubus_msg_from_blob(false);
 533         if (ub != NULL) {
 534                 ubus_msg_init(ub, UBUS_MSG_UNSUBSCRIBE, ++s->subscriber->invoke_seq, 0);
 535                 ubus_msg_send(s->subscriber->client, ub, true);
 536         }
 537
 538         ubus_unsubscribe(s);
 539 }
 540
 541 static void __constructor ubusd_proto_init(void)
 542 {
 543         ubus_init_id_tree(&clients);
 544
 545         blob_buf_init(&b, 0);
 546         blob_put_int32(&b, UBUS_ATTR_STATUS, 0);
 547
 548         retmsg = ubus_msg_from_blob(false);
 549         if (!retmsg)
 550                 exit(1);
 551
 552         retmsg->hdr.type = UBUS_MSG_STATUS;
 553         retmsg_data = blob_data(blob_data(retmsg->data));
 554 }