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         ubus_proto_send_msg_from_blob(cl, ub, UBUS_MSG_DATA);
 134         ubusd_free_object(obj);
 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] && obj->type)
 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 all_cnt = 0, cnt = 0;
 160         void *s;
 161
 162         if (!obj->type)
 163                 return;
 164
 165         blob_buf_init(&b, 0);
 166
 167         blob_put_string(&b, UBUS_ATTR_OBJPATH, obj->path.key);
 168         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
 169         blob_put_int32(&b, UBUS_ATTR_OBJTYPE, obj->type->id.id);
 170
 171         s = blob_nest_start(&b, UBUS_ATTR_SIGNATURE);
 172         list_for_each_entry(m, &obj->type->methods, list) {
 173                 all_cnt++;
 174                 if (!ubusd_acl_check(cl, obj->path.key, blobmsg_name(m->data), UBUS_ACL_ACCESS)) {
 175                         blobmsg_add_blob(&b, m->data);
 176                         cnt++;
 177                 }
 178         }
 179         blob_nest_end(&b, s);
 180
 181         if (cnt || !all_cnt)
 182                 ubus_proto_send_msg_from_blob(cl, ub, UBUS_MSG_DATA);
 183 }
 184
 185 static int ubusd_handle_lookup(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 186 {
 187         struct ubus_object *obj;
 188         char *objpath;
 189         bool found = false;
 190         int len;
 191
 192         if (!attr[UBUS_ATTR_OBJPATH]) {
 193                 avl_for_each_element(&path, obj, path)
 194                         ubusd_send_obj(cl, ub, obj);
 195                 return 0;
 196         }
 197
 198         objpath = blob_data(attr[UBUS_ATTR_OBJPATH]);
 199         len = strlen(objpath);
 200         if (objpath[len - 1] != '*') {
 201                 obj = avl_find_element(&path, objpath, obj, path);
 202                 if (!obj)
 203                         return UBUS_STATUS_NOT_FOUND;
 204
 205                 ubusd_send_obj(cl, ub, obj);
 206                 return 0;
 207         }
 208
 209         objpath[--len] = 0;
 210
 211         obj = avl_find_ge_element(&path, objpath, obj, path);
 212         if (!obj)
 213                 return UBUS_STATUS_NOT_FOUND;
 214
 215         while (!strncmp(objpath, obj->path.key, len)) {
 216                 found = true;
 217                 ubusd_send_obj(cl, ub, obj);
 218                 if (obj == avl_last_element(&path, obj, path))
 219                         break;
 220                 obj = avl_next_element(obj, path);
 221         }
 222
 223         if (!found)
 224                 return UBUS_STATUS_NOT_FOUND;
 225
 226         return 0;
 227 }
 228
 229 static void
 230 ubusd_forward_invoke(struct ubus_client *cl, struct ubus_object *obj,
 231                      const char *method, struct ubus_msg_buf *ub,
 232                      struct blob_attr *data)
 233 {
 234         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
 235         blob_put_string(&b, UBUS_ATTR_METHOD, method);
 236         if (cl->user)
 237                 blob_put_string(&b, UBUS_ATTR_USER, cl->user);
 238         if (cl->group)
 239                 blob_put_string(&b, UBUS_ATTR_GROUP, cl->group);
 240         if (data)
 241                 blob_put(&b, UBUS_ATTR_DATA, blob_data(data), blob_len(data));
 242
 243         ubus_proto_send_msg_from_blob(obj->client, ub, UBUS_MSG_INVOKE);
 244 }
 245
 246 static int ubusd_handle_invoke(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 247 {
 248         struct ubus_object *obj = NULL;
 249         struct ubus_id *id;
 250         const char *method;
 251
 252         if (!attr[UBUS_ATTR_METHOD] || !attr[UBUS_ATTR_OBJID])
 253                 return UBUS_STATUS_INVALID_ARGUMENT;
 254
 255         id = ubus_find_id(&objects, blob_get_u32(attr[UBUS_ATTR_OBJID]));
 256         if (!id)
 257                 return UBUS_STATUS_NOT_FOUND;
 258
 259         obj = container_of(id, struct ubus_object, id);
 260
 261         method = blob_data(attr[UBUS_ATTR_METHOD]);
 262
 263         if (ubusd_acl_check(cl, obj->path.key, method, UBUS_ACL_ACCESS))
 264                 return UBUS_STATUS_PERMISSION_DENIED;
 265
 266         if (!obj->client)
 267                 return obj->recv_msg(cl, ub, method, attr[UBUS_ATTR_DATA]);
 268
 269         ub->hdr.peer = cl->id.id;
 270         blob_buf_init(&b, 0);
 271
 272         ubusd_forward_invoke(cl, obj, method, ub, attr[UBUS_ATTR_DATA]);
 273         ubus_msg_free(ub);
 274
 275         return -1;
 276 }
 277
 278 static int ubusd_handle_notify(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 279 {
 280         struct ubus_object *obj = NULL;
 281         struct ubus_subscription *s;
 282         struct ubus_id *id;
 283         const char *method;
 284         bool no_reply = false;
 285         void *c;
 286
 287         if (!attr[UBUS_ATTR_METHOD] || !attr[UBUS_ATTR_OBJID])
 288                 return UBUS_STATUS_INVALID_ARGUMENT;
 289
 290         if (attr[UBUS_ATTR_NO_REPLY])
 291                 no_reply = blob_get_int8(attr[UBUS_ATTR_NO_REPLY]);
 292
 293         id = ubus_find_id(&objects, blob_get_u32(attr[UBUS_ATTR_OBJID]));
 294         if (!id)
 295                 return UBUS_STATUS_NOT_FOUND;
 296
 297         obj = container_of(id, struct ubus_object, id);
 298         if (obj->client != cl)
 299                 return UBUS_STATUS_PERMISSION_DENIED;
 300
 301         if (!no_reply) {
 302                 blob_buf_init(&b, 0);
 303                 blob_put_int32(&b, UBUS_ATTR_OBJID, id->id);
 304                 c = blob_nest_start(&b, UBUS_ATTR_SUBSCRIBERS);
 305                 list_for_each_entry(s, &obj->subscribers, list) {
 306                         blob_put_int32(&b, 0, s->subscriber->id.id);
 307                 }
 308                 blob_nest_end(&b, c);
 309                 blob_put_int32(&b, UBUS_ATTR_STATUS, 0);
 310                 ubus_proto_send_msg_from_blob(cl, ub, UBUS_MSG_STATUS);
 311         }
 312
 313         ub->hdr.peer = cl->id.id;
 314         method = blob_data(attr[UBUS_ATTR_METHOD]);
 315         list_for_each_entry(s, &obj->subscribers, list) {
 316                 blob_buf_init(&b, 0);
 317                 if (no_reply)
 318                         blob_put_int8(&b, UBUS_ATTR_NO_REPLY, 1);
 319                 ubusd_forward_invoke(cl, s->subscriber, method, ub, attr[UBUS_ATTR_DATA]);
 320         }
 321         ubus_msg_free(ub);
 322
 323         return -1;
 324 }
 325
 326 static struct ubus_client *ubusd_get_client_by_id(uint32_t id)
 327 {
 328         struct ubus_id *clid;
 329
 330         clid = ubus_find_id(&clients, id);
 331         if (!clid)
 332                 return NULL;
 333
 334         return container_of(clid, struct ubus_client, id);
 335 }
 336
 337 static int ubusd_handle_response(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 338 {
 339         struct ubus_object *obj;
 340
 341         if (!attr[UBUS_ATTR_OBJID] ||
 342             (ub->hdr.type == UBUS_MSG_STATUS && !attr[UBUS_ATTR_STATUS]) ||
 343             (ub->hdr.type == UBUS_MSG_DATA && !attr[UBUS_ATTR_DATA]))
 344                 goto error;
 345
 346         obj = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_OBJID]));
 347         if (!obj)
 348                 goto error;
 349
 350         if (cl != obj->client)
 351                 goto error;
 352
 353         cl = ubusd_get_client_by_id(ub->hdr.peer);
 354         if (!cl)
 355                 goto error;
 356
 357         ub->hdr.peer = blob_get_u32(attr[UBUS_ATTR_OBJID]);
 358         ubus_msg_send(cl, ub, true);
 359         return -1;
 360
 361 error:
 362         ubus_msg_free(ub);
 363         return -1;
 364 }
 365
 366 static int ubusd_handle_add_watch(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 367 {
 368         struct ubus_object *obj, *target;
 369
 370         if (!attr[UBUS_ATTR_OBJID] || !attr[UBUS_ATTR_TARGET])
 371                 return UBUS_STATUS_INVALID_ARGUMENT;
 372
 373         obj = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_OBJID]));
 374         if (!obj)
 375                 return UBUS_STATUS_NOT_FOUND;
 376
 377         if (cl != obj->client)
 378                 return UBUS_STATUS_INVALID_ARGUMENT;
 379
 380         target = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_TARGET]));
 381         if (!target || !target->client)
 382                 return UBUS_STATUS_NOT_FOUND;
 383
 384         if (cl == target->client)
 385                 return UBUS_STATUS_INVALID_ARGUMENT;
 386
 387         if (!target->path.key) {
 388                 if (strcmp(target->client->user, cl->user) && strcmp(target->client->group, cl->group))
 389                         return UBUS_STATUS_NOT_FOUND;
 390         } else if (ubusd_acl_check(cl, target->path.key, NULL, UBUS_ACL_SUBSCRIBE)) {
 391                 return UBUS_STATUS_NOT_FOUND;
 392         }
 393
 394         ubus_subscribe(obj, target);
 395         return 0;
 396 }
 397
 398 static int ubusd_handle_remove_watch(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 399 {
 400         struct ubus_object *obj;
 401         struct ubus_subscription *s;
 402         uint32_t id;
 403
 404         if (!attr[UBUS_ATTR_OBJID] || !attr[UBUS_ATTR_TARGET])
 405                 return UBUS_STATUS_INVALID_ARGUMENT;
 406
 407         obj = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_OBJID]));
 408         if (!obj)
 409                 return UBUS_STATUS_NOT_FOUND;
 410
 411         if (cl != obj->client)
 412                 return UBUS_STATUS_INVALID_ARGUMENT;
 413
 414         id = blob_get_u32(attr[UBUS_ATTR_TARGET]);
 415         list_for_each_entry(s, &obj->target_list, target_list) {
 416                 if (s->target->id.id != id)
 417                         continue;
 418
 419                 ubus_unsubscribe(s);
 420                 return 0;
 421         }
 422
 423         return UBUS_STATUS_NOT_FOUND;
 424 }
 425
 426 static const ubus_cmd_cb handlers[__UBUS_MSG_LAST] = {
 427         [UBUS_MSG_PING] = ubusd_send_pong,
 428         [UBUS_MSG_ADD_OBJECT] = ubusd_handle_add_object,
 429         [UBUS_MSG_REMOVE_OBJECT] = ubusd_handle_remove_object,
 430         [UBUS_MSG_LOOKUP] = ubusd_handle_lookup,
 431         [UBUS_MSG_INVOKE] = ubusd_handle_invoke,
 432         [UBUS_MSG_STATUS] = ubusd_handle_response,
 433         [UBUS_MSG_DATA] = ubusd_handle_response,
 434         [UBUS_MSG_SUBSCRIBE] = ubusd_handle_add_watch,
 435         [UBUS_MSG_UNSUBSCRIBE] = ubusd_handle_remove_watch,
 436         [UBUS_MSG_NOTIFY] = ubusd_handle_notify,
 437 };
 438
 439 void ubusd_proto_receive_message(struct ubus_client *cl, struct ubus_msg_buf *ub)
 440 {
 441         ubus_cmd_cb cb = NULL;
 442         int ret;
 443
 444         retmsg->hdr.seq = ub->hdr.seq;
 445         retmsg->hdr.peer = ub->hdr.peer;
 446
 447         if (ub->hdr.type < __UBUS_MSG_LAST)
 448                 cb = handlers[ub->hdr.type];
 449
 450         if (ub->hdr.type != UBUS_MSG_STATUS)
 451                 ubus_msg_close_fd(ub);
 452
 453         if (cb)
 454                 ret = cb(cl, ub, ubus_parse_msg(ub->data));
 455         else
 456                 ret = UBUS_STATUS_INVALID_COMMAND;
 457
 458         if (ret == -1)
 459                 return;
 460
 461         ubus_msg_free(ub);
 462
 463         *retmsg_data = htonl(ret);
 464         ubus_msg_send(cl, retmsg, false);
 465 }
 466
 467 struct ubus_client *ubusd_proto_new_client(int fd, uloop_fd_handler cb)
 468 {
 469         struct ubus_client *cl;
 470
 471         cl = calloc(1, sizeof(*cl));
 472         if (!cl)
 473                 return NULL;
 474
 475         if (ubusd_acl_init_client(cl, fd))
 476                 goto free;
 477
 478         INIT_LIST_HEAD(&cl->objects);
 479         cl->sock.fd = fd;
 480         cl->sock.cb = cb;
 481         cl->pending_msg_fd = -1;
 482
 483         if (!ubus_alloc_id(&clients, &cl->id, 0))
 484                 goto free;
 485
 486         if (!ubusd_send_hello(cl))
 487                 goto delete;
 488
 489         return cl;
 490
 491 delete:
 492         ubus_free_id(&clients, &cl->id);
 493 free:
 494         free(cl);
 495         return NULL;
 496 }
 497
 498 void ubusd_proto_free_client(struct ubus_client *cl)
 499 {
 500         struct ubus_object *obj;
 501
 502         while (!list_empty(&cl->objects)) {
 503                 obj = list_first_entry(&cl->objects, struct ubus_object, list);
 504                 ubusd_free_object(obj);
 505         }
 506
 507         ubusd_acl_free_client(cl);
 508         ubus_free_id(&clients, &cl->id);
 509 }
 510
 511 void ubus_notify_subscription(struct ubus_object *obj)
 512 {
 513         bool active = !list_empty(&obj->subscribers);
 514         struct ubus_msg_buf *ub;
 515
 516         blob_buf_init(&b, 0);
 517         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
 518         blob_put_int8(&b, UBUS_ATTR_ACTIVE, active);
 519
 520         ub = ubus_msg_from_blob(false);
 521         if (!ub)
 522                 return;
 523
 524         ubus_msg_init(ub, UBUS_MSG_NOTIFY, ++obj->invoke_seq, 0);
 525         ubus_msg_send(obj->client, ub, true);
 526 }
 527
 528 void ubus_notify_unsubscribe(struct ubus_subscription *s)
 529 {
 530         struct ubus_msg_buf *ub;
 531
 532         blob_buf_init(&b, 0);
 533         blob_put_int32(&b, UBUS_ATTR_OBJID, s->subscriber->id.id);
 534         blob_put_int32(&b, UBUS_ATTR_TARGET, s->target->id.id);
 535
 536         ub = ubus_msg_from_blob(false);
 537         if (ub != NULL) {
 538                 ubus_msg_init(ub, UBUS_MSG_UNSUBSCRIBE, ++s->subscriber->invoke_seq, 0);
 539                 ubus_msg_send(s->subscriber->client, ub, true);
 540         }
 541
 542         ubus_unsubscribe(s);
 543 }
 544
 545 static void __constructor ubusd_proto_init(void)
 546 {
 547         ubus_init_id_tree(&clients);
 548
 549         blob_buf_init(&b, 0);
 550         blob_put_int32(&b, UBUS_ATTR_STATUS, 0);
 551
 552         retmsg = ubus_msg_from_blob(false);
 553         if (!retmsg)
 554                 exit(1);
 555
 556         retmsg->hdr.type = UBUS_MSG_STATUS;
 557         retmsg_data = blob_data(blob_data(retmsg->data));
 558 }