libubus.c

   1 /*
   2  * Copyright (C) 2011 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 <sys/types.h>
  15 #include <sys/uio.h>
  16 #include <sys/socket.h>
  17 #include <fcntl.h>
  18 #include <unistd.h>
  19 #include <poll.h>
  20
  21 #include <libubox/blob.h>
  22 #include <libubox/blobmsg.h>
  23 #include <libubox/usock.h>
  24
  25 #include "libubus.h"
  26 #include "ubusmsg.h"
  27
  28 #define STATIC_IOV(_var) { .iov_base = (char *) &(_var), .iov_len = sizeof(_var) }
  29
  30 const char *__ubus_strerror[__UBUS_STATUS_LAST] = {
  31         [UBUS_STATUS_OK] = "Success",
  32         [UBUS_STATUS_INVALID_COMMAND] = "Invalid command",
  33         [UBUS_STATUS_INVALID_ARGUMENT] = "Invalid argument",
  34         [UBUS_STATUS_METHOD_NOT_FOUND] = "Method not found",
  35         [UBUS_STATUS_NOT_FOUND] = "Not found",
  36         [UBUS_STATUS_NO_DATA] = "No response",
  37         [UBUS_STATUS_PERMISSION_DENIED] = "Permission denied",
  38         [UBUS_STATUS_TIMEOUT] = "Request timed out",
  39         [UBUS_STATUS_NOT_SUPPORTED] = "Operation not supported",
  40         [UBUS_STATUS_UNKNOWN_ERROR] = "Unknown error",
  41 };
  42
  43 static struct blob_buf b;
  44
  45 static const struct blob_attr_info ubus_policy[UBUS_ATTR_MAX] = {
  46         [UBUS_ATTR_STATUS] = { .type = BLOB_ATTR_INT32 },
  47         [UBUS_ATTR_OBJID] = { .type = BLOB_ATTR_INT32 },
  48         [UBUS_ATTR_OBJPATH] = { .type = BLOB_ATTR_STRING },
  49         [UBUS_ATTR_METHOD] = { .type = BLOB_ATTR_STRING },
  50 };
  51 static struct blob_attr *attrbuf[UBUS_ATTR_MAX];
  52
  53 struct ubus_pending_data {
  54         struct list_head list;
  55         int type;
  56         struct blob_attr data[];
  57 };
  58
  59 struct ubus_pending_invoke {
  60         struct list_head list;
  61         struct ubus_msghdr hdr;
  62 };
  63
  64 static void ubus_process_pending_invoke(struct ubus_context *ctx);
  65
  66 static int ubus_cmp_id(const void *k1, const void *k2, void *ptr)
  67 {
  68         const uint32_t *id1 = k1, *id2 = k2;
  69
  70         if (*id1 < *id2)
  71                 return -1;
  72         else
  73                 return *id1 > *id2;
  74 }
  75
  76 static struct blob_attr **ubus_parse_msg(struct blob_attr *msg)
  77 {
  78         blob_parse(msg, attrbuf, ubus_policy, UBUS_ATTR_MAX);
  79         return attrbuf;
  80 }
  81
  82 const char *ubus_strerror(int error)
  83 {
  84         static char err[32];
  85
  86         if (error < 0 || error >= __UBUS_STATUS_LAST)
  87                 goto out;
  88
  89         if (!__ubus_strerror[error])
  90                 goto out;
  91
  92         return __ubus_strerror[error];
  93
  94 out:
  95         sprintf(err, "Unknown error: %d", error);
  96         return err;
  97 }
  98
  99 static void wait_data(int fd, bool write)
 100 {
 101         struct pollfd pfd = { .fd = fd };
 102
 103         pfd.events = write ? POLLOUT : POLLIN;
 104         poll(&pfd, 1, 0);
 105 }
 106
 107 static int writev_retry(int fd, struct iovec *iov, int iov_len)
 108 {
 109         int len = 0;
 110
 111         do {
 112                 int cur_len = writev(fd, iov, iov_len);
 113                 if (cur_len < 0) {
 114                         switch(errno) {
 115                         case EAGAIN:
 116                                 wait_data(fd, true);
 117                                 break;
 118                         case EINTR:
 119                                 break;
 120                         default:
 121                                 return -1;
 122                         }
 123                         continue;
 124                 }
 125                 len += cur_len;
 126                 while (cur_len >= iov->iov_len) {
 127                         cur_len -= iov->iov_len;
 128                         iov_len--;
 129                         iov++;
 130                         if (!cur_len || !iov_len)
 131                                 return len;
 132                 }
 133                 iov->iov_len -= cur_len;
 134         } while (1);
 135 }
 136
 137 static int ubus_send_msg(struct ubus_context *ctx, uint32_t seq,
 138                          struct blob_attr *msg, int cmd, uint32_t peer)
 139 {
 140         struct ubus_msghdr hdr;
 141         struct iovec iov[2] = {
 142                 STATIC_IOV(hdr)
 143         };
 144
 145         hdr.version = 0;
 146         hdr.type = cmd;
 147         hdr.seq = seq;
 148         hdr.peer = peer;
 149
 150         if (!msg) {
 151                 blob_buf_init(&b, 0);
 152                 msg = b.head;
 153         }
 154
 155         iov[1].iov_base = (char *) msg;
 156         iov[1].iov_len = blob_raw_len(msg);
 157
 158         return writev_retry(ctx->sock.fd, iov, ARRAY_SIZE(iov));
 159 }
 160
 161 static int ubus_start_request(struct ubus_context *ctx, struct ubus_request *req,
 162                               struct blob_attr *msg, int cmd, uint32_t peer)
 163 {
 164         memset(req, 0, sizeof(*req));
 165
 166         if (msg && blob_pad_len(msg) > UBUS_MAX_MSGLEN)
 167                 return -1;
 168
 169         INIT_LIST_HEAD(&req->list);
 170         INIT_LIST_HEAD(&req->pending);
 171         req->ctx = ctx;
 172         req->peer = peer;
 173         req->seq = ++ctx->request_seq;
 174         return ubus_send_msg(ctx, req->seq, msg, cmd, peer);
 175 }
 176
 177 static bool recv_retry(int fd, struct iovec *iov, bool wait)
 178 {
 179         int bytes;
 180
 181         while (iov->iov_len > 0) {
 182                 if (wait)
 183                         wait_data(fd, false);
 184
 185                 bytes = read(fd, iov->iov_base, iov->iov_len);
 186                 if (bytes < 0) {
 187                         bytes = 0;
 188                         if (uloop_cancelled)
 189                                 return false;
 190                         if (errno == EINTR)
 191                                 continue;
 192
 193                         if (errno != EAGAIN)
 194                                 return false;
 195                 }
 196                 if (!wait && !bytes)
 197                         return false;
 198
 199                 wait = true;
 200                 iov->iov_len -= bytes;
 201                 iov->iov_base += bytes;
 202         }
 203
 204         return true;
 205 }
 206
 207 static bool ubus_validate_hdr(struct ubus_msghdr *hdr)
 208 {
 209         if (hdr->version != 0)
 210                 return false;
 211
 212         if (blob_raw_len(hdr->data) < sizeof(*hdr->data))
 213                 return false;
 214
 215         if (blob_pad_len(hdr->data) > UBUS_MAX_MSGLEN)
 216                 return false;
 217
 218         return true;
 219 }
 220
 221 static bool get_next_msg(struct ubus_context *ctx)
 222 {
 223         struct iovec iov = STATIC_IOV(ctx->msgbuf.hdr);
 224
 225         /* receive header + start attribute */
 226         iov.iov_len += sizeof(struct blob_attr);
 227         if (!recv_retry(ctx->sock.fd, &iov, false))
 228                 return false;
 229
 230         iov.iov_len = blob_len(ctx->msgbuf.hdr.data);
 231         if (iov.iov_len > 0 && !recv_retry(ctx->sock.fd, &iov, true))
 232                 return false;
 233
 234         return ubus_validate_hdr(&ctx->msgbuf.hdr);
 235 }
 236
 237 static bool ubus_get_status(struct ubus_msghdr *hdr, int *ret)
 238 {
 239         ubus_parse_msg(hdr->data);
 240
 241         if (!attrbuf[UBUS_ATTR_STATUS])
 242                 return false;
 243
 244         *ret = blob_get_u32(attrbuf[UBUS_ATTR_STATUS]);
 245         return true;
 246 }
 247
 248 static void req_data_cb(struct ubus_request *req, int type, struct blob_attr *data)
 249 {
 250         struct blob_attr **attr;
 251
 252         if (req->raw_data_cb)
 253                 req->raw_data_cb(req, type, data);
 254
 255         if (!req->data_cb)
 256                 return;
 257
 258         attr = ubus_parse_msg(data);
 259         req->data_cb(req, type, attr[UBUS_ATTR_DATA]);
 260 }
 261
 262 static void ubus_process_req_data(struct ubus_request *req)
 263 {
 264         struct ubus_pending_data *data;
 265
 266         while (!list_empty(&req->pending)) {
 267                 data = list_first_entry(&req->pending,
 268                         struct ubus_pending_data, list);
 269                 list_del(&data->list);
 270                 if (!req->cancelled)
 271                         req_data_cb(req, data->type, data->data);
 272                 free(data);
 273         }
 274 }
 275
 276 static void ubus_req_complete_cb(struct ubus_request *req)
 277 {
 278         ubus_complete_handler_t cb = req->complete_cb;
 279
 280         if (!cb)
 281                 return;
 282
 283         req->complete_cb = NULL;
 284         cb(req, req->status_code);
 285 }
 286
 287 static int ubus_process_req_status(struct ubus_request *req, struct ubus_msghdr *hdr)
 288 {
 289         int ret = UBUS_STATUS_INVALID_ARGUMENT;
 290
 291         if (!list_empty(&req->list))
 292                 list_del_init(&req->list);
 293
 294         ubus_get_status(hdr, &ret);
 295         req->peer = hdr->peer;
 296         req->status_msg = true;
 297         req->status_code = ret;
 298         if (!req->blocked)
 299                 ubus_req_complete_cb(req);
 300
 301         return ret;
 302 }
 303
 304 static void ubus_req_data(struct ubus_request *req, struct ubus_msghdr *hdr)
 305 {
 306         struct ubus_pending_data *data;
 307         int len;
 308
 309         if (!req->blocked) {
 310                 req->blocked = true;
 311                 req_data_cb(req, hdr->type, hdr->data);
 312                 ubus_process_req_data(req);
 313                 req->blocked = false;
 314
 315                 if (req->status_msg)
 316                         ubus_req_complete_cb(req);
 317
 318                 return;
 319         }
 320
 321         len = blob_raw_len(hdr->data);
 322         data = calloc(1, sizeof(*data) + len);
 323         if (!data)
 324                 return;
 325
 326         data->type = hdr->type;
 327         memcpy(data->data, hdr->data, len);
 328         list_add(&data->list, &req->pending);
 329 }
 330
 331 static struct ubus_request *ubus_find_request(struct ubus_context *ctx, uint32_t seq, uint32_t peer)
 332 {
 333         struct ubus_request *req;
 334
 335         list_for_each_entry(req, &ctx->requests, list) {
 336                 if (seq != req->seq || peer != req->peer)
 337                         continue;
 338
 339                 return req;
 340         }
 341         return NULL;
 342 }
 343
 344 static void ubus_process_invoke(struct ubus_context *ctx, struct ubus_msghdr *hdr)
 345 {
 346         struct ubus_request_data req;
 347         struct ubus_object *obj;
 348         uint32_t objid = 0;
 349         int method;
 350         int ret = 0;
 351
 352         req.peer = hdr->peer;
 353         req.seq = hdr->seq;
 354         ubus_parse_msg(hdr->data);
 355
 356         if (!attrbuf[UBUS_ATTR_OBJID])
 357                 return;
 358
 359         objid = blob_get_u32(attrbuf[UBUS_ATTR_OBJID]);
 360
 361         if (!attrbuf[UBUS_ATTR_METHOD]) {
 362                 ret = UBUS_STATUS_INVALID_ARGUMENT;
 363                 goto send;
 364         }
 365
 366         obj = avl_find_element(&ctx->objects, &objid, obj, avl);
 367         if (!obj) {
 368                 ret = UBUS_STATUS_NOT_FOUND;
 369                 goto send;
 370         }
 371
 372         for (method = 0; method < obj->n_methods; method++)
 373                 if (!obj->methods[method].name ||
 374                     !strcmp(obj->methods[method].name,
 375                             blob_data(attrbuf[UBUS_ATTR_METHOD])))
 376                         goto found;
 377
 378         /* not found */
 379         ret = UBUS_STATUS_METHOD_NOT_FOUND;
 380         goto send;
 381
 382 found:
 383         req.object = objid;
 384         ret = obj->methods[method].handler(ctx, obj, &req,
 385                                            blob_data(attrbuf[UBUS_ATTR_METHOD]),
 386                                            attrbuf[UBUS_ATTR_DATA]);
 387
 388 send:
 389         blob_buf_init(&b, 0);
 390         blob_put_int32(&b, UBUS_ATTR_STATUS, ret);
 391         blob_put_int32(&b, UBUS_ATTR_OBJID, objid);
 392         ubus_send_msg(ctx, req.seq, b.head, UBUS_MSG_STATUS, req.peer);
 393 }
 394
 395 static void ubus_process_msg(struct ubus_context *ctx, struct ubus_msghdr *hdr)
 396 {
 397         struct ubus_pending_invoke *pending;
 398         struct ubus_request *req;
 399
 400         switch(hdr->type) {
 401         case UBUS_MSG_STATUS:
 402                 req = ubus_find_request(ctx, hdr->seq, hdr->peer);
 403                 if (!req)
 404                         break;
 405
 406                 ubus_process_req_status(req, hdr);
 407                 break;
 408
 409         case UBUS_MSG_DATA:
 410                 req = ubus_find_request(ctx, hdr->seq, hdr->peer);
 411                 if (req && (req->data_cb || req->raw_data_cb))
 412                         ubus_req_data(req, hdr);
 413                 break;
 414
 415         case UBUS_MSG_INVOKE:
 416                 if (ctx->stack_depth > 2) {
 417                         pending = calloc(1, sizeof(*pending) +
 418                                 blob_raw_len(hdr->data));
 419
 420                         if (!pending)
 421                                 return;
 422
 423                         memcpy(&pending->hdr, hdr, sizeof(*hdr) +
 424                                 blob_raw_len(hdr->data));
 425                         list_add(&pending->list, &ctx->pending);
 426                 } else {
 427                         ubus_process_invoke(ctx, hdr);
 428                 }
 429                 break;
 430         }
 431 }
 432
 433 static void ubus_process_pending_invoke(struct ubus_context *ctx)
 434 {
 435         struct ubus_pending_invoke *pending, *tmp;
 436
 437         list_for_each_entry_safe(pending, tmp, &ctx->pending, list) {
 438                 list_del(&pending->list);
 439                 ubus_process_msg(ctx, &pending->hdr);
 440                 free(pending);
 441                 if (ctx->stack_depth > 2)
 442                         break;
 443         }
 444 }
 445
 446 void ubus_abort_request(struct ubus_context *ctx, struct ubus_request *req)
 447 {
 448         if (!list_empty(&req->list))
 449                 return;
 450
 451         req->cancelled = true;
 452         ubus_process_req_data(req);
 453         list_del_init(&req->list);
 454 }
 455
 456 void ubus_complete_request_async(struct ubus_context *ctx, struct ubus_request *req)
 457 {
 458         if (!list_empty(&req->list))
 459                 return;
 460
 461         list_add(&req->list, &ctx->requests);
 462 }
 463
 464 static void ubus_handle_data(struct uloop_fd *u, unsigned int events)
 465 {
 466         struct ubus_context *ctx = container_of(u, struct ubus_context, sock);
 467         struct ubus_msghdr *hdr = &ctx->msgbuf.hdr;
 468
 469         while (get_next_msg(ctx)) {
 470                 ubus_process_msg(ctx, hdr);
 471                 if (uloop_cancelled)
 472                         break;
 473         }
 474
 475         if (u->eof)
 476                 ctx->connection_lost(ctx);
 477 }
 478
 479 static void ubus_sync_req_cb(struct ubus_request *req, int ret)
 480 {
 481         req->status_msg = true;
 482         req->status_code = ret;
 483         uloop_end();
 484 }
 485
 486 struct ubus_sync_req_cb {
 487         struct uloop_timeout timeout;
 488         struct ubus_request *req;
 489 };
 490
 491 static void ubus_sync_req_timeout_cb(struct uloop_timeout *timeout)
 492 {
 493         struct ubus_sync_req_cb *cb;
 494
 495         cb = container_of(timeout, struct ubus_sync_req_cb, timeout);
 496         ubus_sync_req_cb(cb->req, UBUS_STATUS_TIMEOUT);
 497 }
 498
 499 int ubus_complete_request(struct ubus_context *ctx, struct ubus_request *req,
 500                           int timeout)
 501 {
 502         struct ubus_sync_req_cb cb;
 503         ubus_complete_handler_t complete_cb = req->complete_cb;
 504         bool registered = ctx->sock.registered;
 505         int status = UBUS_STATUS_NO_DATA;
 506
 507         if (!registered) {
 508                 uloop_init();
 509                 ubus_add_uloop(ctx);
 510         }
 511
 512         if (timeout) {
 513                 memset(&cb, 0, sizeof(cb));
 514                 cb.req = req;
 515                 cb.timeout.cb = ubus_sync_req_timeout_cb;
 516                 uloop_timeout_set(&cb.timeout, timeout);
 517         }
 518
 519         ubus_complete_request_async(ctx, req);
 520         req->complete_cb = ubus_sync_req_cb;
 521
 522         ctx->stack_depth++;
 523         while (!req->status_msg) {
 524                 bool cancelled = uloop_cancelled;
 525                 uloop_cancelled = false;
 526                 uloop_run();
 527                 uloop_cancelled = cancelled;
 528         }
 529         ctx->stack_depth--;
 530
 531         if (timeout)
 532                 uloop_timeout_cancel(&cb.timeout);
 533
 534         if (req->status_msg)
 535                 status = req->status_code;
 536
 537         req->complete_cb = complete_cb;
 538         if (req->complete_cb)
 539                 req->complete_cb(req, status);
 540
 541         if (!registered)
 542                 uloop_fd_delete(&ctx->sock);
 543
 544         if (!ctx->stack_depth)
 545                 ubus_process_pending_invoke(ctx);
 546
 547         return status;
 548 }
 549
 550 struct ubus_lookup_request {
 551         struct ubus_request req;
 552         ubus_lookup_handler_t cb;
 553 };
 554
 555 static void ubus_lookup_cb(struct ubus_request *ureq, int type, struct blob_attr *msg)
 556 {
 557         struct ubus_lookup_request *req;
 558         struct ubus_object_data obj;
 559         struct blob_attr **attr;
 560
 561         req = container_of(ureq, struct ubus_lookup_request, req);
 562         attr = ubus_parse_msg(msg);
 563
 564         if (!attr[UBUS_ATTR_OBJID] || !attr[UBUS_ATTR_OBJPATH] ||
 565             !attr[UBUS_ATTR_OBJTYPE])
 566                 return;
 567
 568         memset(&obj, 0, sizeof(obj));
 569         obj.id = blob_get_u32(attr[UBUS_ATTR_OBJID]);
 570         obj.path = blob_data(attr[UBUS_ATTR_OBJPATH]);
 571         obj.type_id = blob_get_u32(attr[UBUS_ATTR_OBJTYPE]);
 572         obj.signature = attr[UBUS_ATTR_SIGNATURE];
 573         req->cb(ureq->ctx, &obj, ureq->priv);
 574 }
 575
 576 int ubus_lookup(struct ubus_context *ctx, const char *path,
 577                 ubus_lookup_handler_t cb, void *priv)
 578 {
 579         struct ubus_lookup_request lookup;
 580
 581         blob_buf_init(&b, 0);
 582         if (path)
 583                 blob_put_string(&b, UBUS_ATTR_OBJPATH, path);
 584
 585         if (ubus_start_request(ctx, &lookup.req, b.head, UBUS_MSG_LOOKUP, 0) < 0)
 586                 return UBUS_STATUS_INVALID_ARGUMENT;
 587
 588         lookup.req.raw_data_cb = ubus_lookup_cb;
 589         lookup.req.priv = priv;
 590         lookup.cb = cb;
 591         return ubus_complete_request(ctx, &lookup.req, 0);
 592 }
 593
 594 static void ubus_lookup_id_cb(struct ubus_request *req, int type, struct blob_attr *msg)
 595 {
 596         struct blob_attr **attr;
 597         uint32_t *id = req->priv;
 598
 599         attr = ubus_parse_msg(msg);
 600
 601         if (!attr[UBUS_ATTR_OBJID])
 602                 return;
 603
 604         *id = blob_get_u32(attr[UBUS_ATTR_OBJID]);
 605 }
 606
 607 int ubus_lookup_id(struct ubus_context *ctx, const char *path, uint32_t *id)
 608 {
 609         struct ubus_request req;
 610
 611         blob_buf_init(&b, 0);
 612         if (path)
 613                 blob_put_string(&b, UBUS_ATTR_OBJPATH, path);
 614
 615         if (ubus_start_request(ctx, &req, b.head, UBUS_MSG_LOOKUP, 0) < 0)
 616                 return UBUS_STATUS_INVALID_ARGUMENT;
 617
 618         req.raw_data_cb = ubus_lookup_id_cb;
 619         req.priv = id;
 620
 621         return ubus_complete_request(ctx, &req, 0);
 622 }
 623
 624 int ubus_send_reply(struct ubus_context *ctx, struct ubus_request_data *req,
 625                     struct blob_attr *msg)
 626 {
 627         int ret;
 628
 629         blob_buf_init(&b, 0);
 630         blob_put_int32(&b, UBUS_ATTR_OBJID, req->object);
 631         blob_put(&b, UBUS_ATTR_DATA, blob_data(msg), blob_len(msg));
 632         ret = ubus_send_msg(ctx, req->seq, b.head, UBUS_MSG_DATA, req->peer);
 633         if (ret < 0)
 634                 return UBUS_STATUS_NO_DATA;
 635
 636         return 0;
 637 }
 638
 639 int ubus_invoke_async(struct ubus_context *ctx, uint32_t obj, const char *method,
 640                        struct blob_attr *msg, struct ubus_request *req)
 641 {
 642         blob_buf_init(&b, 0);
 643         blob_put_int32(&b, UBUS_ATTR_OBJID, obj);
 644         blob_put_string(&b, UBUS_ATTR_METHOD, method);
 645         if (msg)
 646                 blob_put(&b, UBUS_ATTR_DATA, blob_data(msg), blob_len(msg));
 647
 648         if (ubus_start_request(ctx, req, b.head, UBUS_MSG_INVOKE, obj) < 0)
 649                 return UBUS_STATUS_INVALID_ARGUMENT;
 650
 651         return 0;
 652 }
 653
 654 int ubus_invoke(struct ubus_context *ctx, uint32_t obj, const char *method,
 655                 struct blob_attr *msg, ubus_data_handler_t cb, void *priv,
 656                 int timeout)
 657 {
 658         struct ubus_request req;
 659
 660         ubus_invoke_async(ctx, obj, method, msg, &req);
 661         req.data_cb = cb;
 662         req.priv = priv;
 663         return ubus_complete_request(ctx, &req, timeout);
 664 }
 665
 666 static void ubus_add_object_cb(struct ubus_request *req, int type, struct blob_attr *msg)
 667 {
 668         struct ubus_object *obj = req->priv;
 669
 670         ubus_parse_msg(msg);
 671
 672         if (!attrbuf[UBUS_ATTR_OBJID])
 673                 return;
 674
 675         obj->id = blob_get_u32(attrbuf[UBUS_ATTR_OBJID]);
 676
 677         if (attrbuf[UBUS_ATTR_OBJTYPE])
 678                 obj->type->id = blob_get_u32(attrbuf[UBUS_ATTR_OBJTYPE]);
 679
 680         obj->avl.key = &obj->id;
 681         avl_insert(&req->ctx->objects, &obj->avl);
 682 }
 683
 684 static void ubus_push_method_data(const struct ubus_method *m)
 685 {
 686         void *mtbl;
 687         int i;
 688
 689         mtbl = blobmsg_open_table(&b, m->name);
 690
 691         for (i = 0; i < m->n_policy; i++)
 692                 blobmsg_add_u32(&b, m->policy[i].name, m->policy[i].type);
 693
 694         blobmsg_close_table(&b, mtbl);
 695 }
 696
 697 static bool ubus_push_object_type(const struct ubus_object_type *type)
 698 {
 699         void *s;
 700         int i;
 701
 702         s = blob_nest_start(&b, UBUS_ATTR_SIGNATURE);
 703
 704         for (i = 0; i < type->n_methods; i++)
 705                 ubus_push_method_data(&type->methods[i]);
 706
 707         blob_nest_end(&b, s);
 708
 709         return true;
 710 }
 711
 712 static int __ubus_add_object(struct ubus_context *ctx, struct ubus_object *obj)
 713 {
 714         struct ubus_request req;
 715         int ret;
 716
 717         blob_buf_init(&b, 0);
 718
 719         if (obj->name && obj->type) {
 720                 blob_put_string(&b, UBUS_ATTR_OBJPATH, obj->name);
 721
 722                 if (obj->type->id)
 723                         blob_put_int32(&b, UBUS_ATTR_OBJTYPE, obj->type->id);
 724                 else if (!ubus_push_object_type(obj->type))
 725                         return UBUS_STATUS_INVALID_ARGUMENT;
 726         }
 727
 728         if (ubus_start_request(ctx, &req, b.head, UBUS_MSG_ADD_OBJECT, 0) < 0)
 729                 return UBUS_STATUS_INVALID_ARGUMENT;
 730
 731         req.raw_data_cb = ubus_add_object_cb;
 732         req.priv = obj;
 733         ret = ubus_complete_request(ctx, &req, 0);
 734         if (ret)
 735                 return ret;
 736
 737         if (!obj->id)
 738                 return UBUS_STATUS_NO_DATA;
 739
 740         return 0;
 741 }
 742
 743 int ubus_add_object(struct ubus_context *ctx, struct ubus_object *obj)
 744 {
 745         if (!obj->name || !obj->type)
 746                 return UBUS_STATUS_INVALID_ARGUMENT;
 747
 748         return __ubus_add_object(ctx, obj);
 749 }
 750
 751 static void ubus_remove_object_cb(struct ubus_request *req, int type, struct blob_attr *msg)
 752 {
 753         struct ubus_object *obj = req->priv;
 754
 755         ubus_parse_msg(msg);
 756
 757         if (!attrbuf[UBUS_ATTR_OBJID])
 758                 return;
 759
 760         obj->id = 0;
 761
 762         if (attrbuf[UBUS_ATTR_OBJTYPE] && obj->type)
 763                 obj->type->id = 0;
 764
 765         avl_delete(&req->ctx->objects, &obj->avl);
 766 }
 767
 768 int ubus_remove_object(struct ubus_context *ctx, struct ubus_object *obj)
 769 {
 770         struct ubus_request req;
 771         int ret;
 772
 773         blob_buf_init(&b, 0);
 774         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id);
 775
 776         if (ubus_start_request(ctx, &req, b.head, UBUS_MSG_REMOVE_OBJECT, 0) < 0)
 777                 return UBUS_STATUS_INVALID_ARGUMENT;
 778
 779         req.raw_data_cb = ubus_remove_object_cb;
 780         req.priv = obj;
 781         ret = ubus_complete_request(ctx, &req, 0);
 782         if (ret)
 783                 return ret;
 784
 785         if (obj->id)
 786                 return UBUS_STATUS_NO_DATA;
 787
 788         return 0;
 789 }
 790
 791 static int ubus_event_cb(struct ubus_context *ctx, struct ubus_object *obj,
 792                          struct ubus_request_data *req,
 793                          const char *method, struct blob_attr *msg)
 794 {
 795         struct ubus_event_handler *ev;
 796
 797         ev = container_of(obj, struct ubus_event_handler, obj);
 798         ev->cb(ctx, ev, method, msg);
 799         return 0;
 800 }
 801
 802 static const struct ubus_method event_method = {
 803         .name = NULL,
 804         .handler = ubus_event_cb,
 805 };
 806
 807 int ubus_register_event_handler(struct ubus_context *ctx,
 808                                 struct ubus_event_handler *ev,
 809                                 const char *pattern)
 810 {
 811         struct ubus_object *obj = &ev->obj;
 812         struct blob_buf b2;
 813         int ret;
 814
 815         if (!obj->id) {
 816                 obj->methods = &event_method;
 817                 obj->n_methods = 1;
 818
 819                 if (!!obj->name ^ !!obj->type)
 820                         return UBUS_STATUS_INVALID_ARGUMENT;
 821
 822                 ret = __ubus_add_object(ctx, obj);
 823                 if (ret)
 824                         return ret;
 825         }
 826
 827         /* use a second buffer, ubus_invoke() overwrites the primary one */
 828         memset(&b2, 0, sizeof(b2));
 829         blob_buf_init(&b2, 0);
 830         blobmsg_add_u32(&b2, "object", obj->id);
 831         if (pattern)
 832                 blobmsg_add_string(&b2, "pattern", pattern);
 833
 834         return ubus_invoke(ctx, UBUS_SYSTEM_OBJECT_EVENT, "register", b2.head,
 835                           NULL, NULL, 0);
 836 }
 837
 838 int ubus_send_event(struct ubus_context *ctx, const char *id,
 839                     struct blob_attr *data)
 840 {
 841         struct ubus_request req;
 842         void *s;
 843
 844         blob_buf_init(&b, 0);
 845         blob_put_int32(&b, UBUS_ATTR_OBJID, UBUS_SYSTEM_OBJECT_EVENT);
 846         blob_put_string(&b, UBUS_ATTR_METHOD, "send");
 847         s = blob_nest_start(&b, UBUS_ATTR_DATA);
 848         blobmsg_add_string(&b, "id", id);
 849         blobmsg_add_field(&b, BLOBMSG_TYPE_TABLE, "data", blob_data(data), blob_len(data));
 850         blob_nest_end(&b, s);
 851
 852         if (ubus_start_request(ctx, &req, b.head, UBUS_MSG_INVOKE, UBUS_SYSTEM_OBJECT_EVENT) < 0)
 853                 return UBUS_STATUS_INVALID_ARGUMENT;
 854
 855         return ubus_complete_request(ctx, &req, 0);
 856 }
 857
 858 static void ubus_default_connection_lost(struct ubus_context *ctx)
 859 {
 860         if (ctx->sock.registered)
 861                 uloop_end();
 862 }
 863
 864 struct ubus_context *ubus_connect(const char *path)
 865 {
 866         struct ubus_context *ctx;
 867         struct {
 868                 struct ubus_msghdr hdr;
 869                 struct blob_attr data;
 870         } hdr;
 871         struct blob_attr *buf;
 872
 873         if (!path)
 874                 path = UBUS_UNIX_SOCKET;
 875
 876         ctx = calloc(1, sizeof(*ctx));
 877         if (!ctx)
 878                 goto error;
 879
 880         ctx->sock.fd = usock(USOCK_UNIX, path, NULL);
 881         if (ctx->sock.fd < 0)
 882                 goto error_free;
 883
 884         ctx->sock.cb = ubus_handle_data;
 885
 886         if (read(ctx->sock.fd, &hdr, sizeof(hdr)) != sizeof(hdr))
 887                 goto error_close;
 888
 889         if (!ubus_validate_hdr(&hdr.hdr))
 890                 goto error_close;
 891
 892         if (hdr.hdr.type != UBUS_MSG_HELLO)
 893                 goto error_close;
 894
 895         buf = calloc(1, blob_raw_len(&hdr.data));
 896         if (!buf)
 897                 goto error_close;
 898
 899         memcpy(buf, &hdr.data, sizeof(hdr.data));
 900         if (read(ctx->sock.fd, blob_data(buf), blob_len(buf)) != blob_len(buf))
 901                 goto error_free_buf;
 902
 903         ctx->local_id = hdr.hdr.peer;
 904         free(buf);
 905
 906         ctx->connection_lost = ubus_default_connection_lost;
 907
 908         INIT_LIST_HEAD(&ctx->requests);
 909         INIT_LIST_HEAD(&ctx->pending);
 910         avl_init(&ctx->objects, ubus_cmp_id, false, NULL);
 911
 912         if (!ctx->local_id)
 913                 goto error_close;
 914
 915         fcntl(ctx->sock.fd, F_SETFL, fcntl(ctx->sock.fd, F_GETFL) | O_NONBLOCK);
 916
 917         return ctx;
 918
 919 error_free_buf:
 920         free(buf);
 921 error_close:
 922         close(ctx->sock.fd);
 923 error_free:
 924         free(ctx);
 925 error:
 926         return NULL;
 927 }
 928
 929 void ubus_free(struct ubus_context *ctx)
 930 {
 931         close(ctx->sock.fd);
 932         free(ctx);
 933 }