ubus.c

   1 /*
   2  * uhttpd - Tiny single-threaded httpd
   3  *
   4  *   Copyright (C) 2010-2013 Jo-Philipp Wich <xm@subsignal.org>
   5  *   Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
   6  *
   7  * Permission to use, copy, modify, and/or distribute this software for any
   8  * purpose with or without fee is hereby granted, provided that the above
   9  * copyright notice and this permission notice appear in all copies.
  10  *
  11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20 #include <libubox/blobmsg.h>
  21 #include <libubox/blobmsg_json.h>
  22 #include <libubox/avl.h>
  23 #include <libubox/avl-cmp.h>
  24 #include <stdio.h>
  25 #include <poll.h>
  26
  27 #include "uhttpd.h"
  28 #include "plugin.h"
  29
  30 static const struct uhttpd_ops *ops;
  31 static struct config *_conf;
  32 #define conf (*_conf)
  33
  34 static struct ubus_context *ctx;
  35 static struct blob_buf buf;
  36
  37 #define UH_UBUS_MAX_POST_SIZE   4096
  38 #define UH_UBUS_DEFAULT_SID     "00000000000000000000000000000000"
  39
  40 enum {
  41         RPC_JSONRPC,
  42         RPC_METHOD,
  43         RPC_PARAMS,
  44         RPC_ID,
  45         __RPC_MAX,
  46 };
  47
  48 static const struct blobmsg_policy rpc_policy[__RPC_MAX] = {
  49         [RPC_JSONRPC] = { .name = "jsonrpc", .type = BLOBMSG_TYPE_STRING },
  50         [RPC_METHOD] = { .name = "method", .type = BLOBMSG_TYPE_STRING },
  51         [RPC_PARAMS] = { .name = "params", .type = BLOBMSG_TYPE_ARRAY },
  52         [RPC_ID] = { .name = "id", .type = BLOBMSG_TYPE_UNSPEC },
  53 };
  54
  55 enum {
  56         SES_ACCESS,
  57         __SES_MAX,
  58 };
  59
  60 static const struct blobmsg_policy ses_policy[__SES_MAX] = {
  61         [SES_ACCESS] = { .name = "access", .type = BLOBMSG_TYPE_BOOL },
  62 };
  63
  64 struct rpc_data {
  65         struct blob_attr *id;
  66         const char *sid;
  67         const char *method;
  68         const char *object;
  69         const char *function;
  70         struct blob_attr *data;
  71         struct blob_attr *params;
  72 };
  73
  74 struct list_data {
  75         bool verbose;
  76         struct blob_buf *buf;
  77 };
  78
  79 enum rpc_error {
  80         ERROR_PARSE,
  81         ERROR_REQUEST,
  82         ERROR_METHOD,
  83         ERROR_PARAMS,
  84         ERROR_INTERNAL,
  85         ERROR_OBJECT,
  86         ERROR_SESSION,
  87         ERROR_ACCESS,
  88         ERROR_TIMEOUT,
  89         __ERROR_MAX
  90 };
  91
  92 static const struct {
  93         int code;
  94         const char *msg;
  95 } json_errors[__ERROR_MAX] = {
  96         [ERROR_PARSE] = { -32700, "Parse error" },
  97         [ERROR_REQUEST] = { -32600, "Invalid request" },
  98         [ERROR_METHOD] = { -32601, "Method not found" },
  99         [ERROR_PARAMS] = { -32602, "Invalid parameters" },
 100         [ERROR_INTERNAL] = { -32603, "Internal error" },
 101         [ERROR_OBJECT] = { -32000, "Object not found" },
 102         [ERROR_SESSION] = { -32001, "Session not found" },
 103         [ERROR_ACCESS] = { -32002, "Access denied" },
 104         [ERROR_TIMEOUT] = { -32003, "ubus request timed out" },
 105 };
 106
 107 static void __uh_ubus_next_batched_request(struct uloop_timeout *timeout);
 108
 109 static void uh_ubus_next_batched_request(struct client *cl)
 110 {
 111         struct dispatch_ubus *du = &cl->dispatch.ubus;
 112
 113         du->timeout.cb = __uh_ubus_next_batched_request;
 114         uloop_timeout_set(&du->timeout, 1);
 115 }
 116
 117 static void uh_ubus_send_header(struct client *cl)
 118 {
 119         ops->http_header(cl, 200, "OK");
 120         ustream_printf(cl->us, "Content-Type: application/json\r\n\r\n");
 121 }
 122
 123 static void uh_ubus_send_response(struct client *cl)
 124 {
 125         struct dispatch_ubus *du = &cl->dispatch.ubus;
 126         const char *sep = "";
 127         char *str;
 128
 129         if (du->array && du->array_idx > 1)
 130                 sep = ", ";
 131
 132         str = blobmsg_format_json_indent(buf.head, true, du->array);
 133         ops->chunk_printf(cl, "%s%s", sep, str);
 134         free(str);
 135
 136         du->jsobj_cur = NULL;
 137         if (du->array)
 138                 uh_ubus_next_batched_request(cl);
 139         else {
 140                 ops->chunk_printf(cl, "\n");
 141                 return ops->request_done(cl);
 142         }
 143 }
 144
 145 static void uh_ubus_init_response(struct client *cl)
 146 {
 147         struct dispatch_ubus *du = &cl->dispatch.ubus;
 148         struct json_object *obj = du->jsobj_cur;
 149
 150         blob_buf_init(&buf, 0);
 151         blobmsg_add_string(&buf, "jsonrpc", "2.0");
 152
 153         if (obj)
 154                 obj = json_object_object_get(obj, "id");
 155
 156         if (obj)
 157                 blobmsg_add_json_element(&buf, "id", obj);
 158         else
 159                 blobmsg_add_field(&buf, BLOBMSG_TYPE_UNSPEC, "id", NULL, 0);
 160 }
 161
 162 static void uh_ubus_json_error(struct client *cl, enum rpc_error type)
 163 {
 164         void *c;
 165
 166         uh_ubus_init_response(cl);
 167         c = blobmsg_open_table(&buf, "error");
 168         blobmsg_add_u32(&buf, "code", json_errors[type].code);
 169         blobmsg_add_string(&buf, "message", json_errors[type].msg);
 170         blobmsg_close_table(&buf, c);
 171         uh_ubus_send_response(cl);
 172 }
 173
 174 static void
 175 uh_ubus_request_data_cb(struct ubus_request *req, int type, struct blob_attr *msg)
 176 {
 177         struct dispatch_ubus *du = container_of(req, struct dispatch_ubus, req);
 178
 179         blobmsg_add_field(&du->buf, BLOBMSG_TYPE_TABLE, "", blob_data(msg), blob_len(msg));
 180 }
 181
 182 static void
 183 uh_ubus_request_cb(struct ubus_request *req, int ret)
 184 {
 185         struct dispatch_ubus *du = container_of(req, struct dispatch_ubus, req);
 186         struct client *cl = container_of(du, struct client, dispatch.ubus);
 187         struct blob_attr *cur;
 188         void *r;
 189         int rem;
 190
 191         uloop_timeout_cancel(&du->timeout);
 192         uh_ubus_init_response(cl);
 193         r = blobmsg_open_array(&buf, "result");
 194         blobmsg_add_u32(&buf, "", ret);
 195         blob_for_each_attr(cur, du->buf.head, rem)
 196                 blobmsg_add_blob(&buf, cur);
 197         blobmsg_close_array(&buf, r);
 198         uh_ubus_send_response(cl);
 199 }
 200
 201 static void
 202 uh_ubus_timeout_cb(struct uloop_timeout *timeout)
 203 {
 204         struct dispatch_ubus *du = container_of(timeout, struct dispatch_ubus, timeout);
 205         struct client *cl = container_of(du, struct client, dispatch.ubus);
 206
 207         ubus_abort_request(ctx, &du->req);
 208         uh_ubus_json_error(cl, ERROR_TIMEOUT);
 209 }
 210
 211 static void uh_ubus_close_fds(struct client *cl)
 212 {
 213         if (ctx->sock.fd < 0)
 214                 return;
 215
 216         close(ctx->sock.fd);
 217         ctx->sock.fd = -1;
 218 }
 219
 220 static void uh_ubus_request_free(struct client *cl)
 221 {
 222         struct dispatch_ubus *du = &cl->dispatch.ubus;
 223
 224         blob_buf_free(&du->buf);
 225         uloop_timeout_cancel(&du->timeout);
 226
 227         if (du->jsobj)
 228                 json_object_put(du->jsobj);
 229
 230         if (du->jstok)
 231                 json_tokener_free(du->jstok);
 232
 233         if (du->req_pending)
 234                 ubus_abort_request(ctx, &du->req);
 235 }
 236
 237 static void uh_ubus_single_error(struct client *cl, enum rpc_error type)
 238 {
 239         uh_ubus_send_header(cl);
 240         uh_ubus_json_error(cl, type);
 241         ops->request_done(cl);
 242 }
 243
 244 static void uh_ubus_send_request(struct client *cl, json_object *obj, const char *sid, struct blob_attr *args)
 245 {
 246         struct dispatch *d = &cl->dispatch;
 247         struct dispatch_ubus *du = &d->ubus;
 248         struct blob_attr *cur;
 249         static struct blob_buf req;
 250         int ret, rem;
 251
 252         blob_buf_init(&req, 0);
 253         blobmsg_for_each_attr(cur, args, rem) {
 254                 if (!strcmp(blobmsg_name(cur), "ubus_rpc_session"))
 255                         return uh_ubus_json_error(cl, ERROR_PARAMS);
 256                 blobmsg_add_blob(&req, cur);
 257         }
 258
 259         blobmsg_add_string(&req, "ubus_rpc_session", sid);
 260
 261         blob_buf_init(&du->buf, 0);
 262         memset(&du->req, 0, sizeof(du->req));
 263         ret = ubus_invoke_async(ctx, du->obj, du->func, req.head, &du->req);
 264         if (ret)
 265                 return uh_ubus_json_error(cl, ERROR_INTERNAL);
 266
 267         du->req.data_cb = uh_ubus_request_data_cb;
 268         du->req.complete_cb = uh_ubus_request_cb;
 269         ubus_complete_request_async(ctx, &du->req);
 270
 271         du->timeout.cb = uh_ubus_timeout_cb;
 272         uloop_timeout_set(&du->timeout, conf.script_timeout * 1000);
 273
 274         du->req_pending = true;
 275 }
 276
 277 static void uh_ubus_list_cb(struct ubus_context *ctx, struct ubus_object_data *obj, void *priv)
 278 {
 279         struct blob_attr *sig, *attr;
 280         struct list_data *data = priv;
 281         int rem, rem2;
 282         void *t, *o;
 283
 284         if (!data->verbose) {
 285                 blobmsg_add_string(data->buf, NULL, obj->path);
 286                 return;
 287         }
 288
 289         if (!obj->signature)
 290                 return;
 291
 292         o = blobmsg_open_table(data->buf, obj->path);
 293         blob_for_each_attr(sig, obj->signature, rem) {
 294                 t = blobmsg_open_table(data->buf, blobmsg_name(sig));
 295                 rem2 = blobmsg_data_len(sig);
 296                 __blob_for_each_attr(attr, blobmsg_data(sig), rem2) {
 297                         if (blob_id(attr) != BLOBMSG_TYPE_INT32)
 298                                 continue;
 299
 300                         switch (blobmsg_get_u32(attr)) {
 301                         case BLOBMSG_TYPE_INT8:
 302                                 blobmsg_add_string(data->buf, blobmsg_name(attr), "boolean");
 303                                 break;
 304                         case BLOBMSG_TYPE_INT32:
 305                                 blobmsg_add_string(data->buf, blobmsg_name(attr), "number");
 306                                 break;
 307                         case BLOBMSG_TYPE_STRING:
 308                                 blobmsg_add_string(data->buf, blobmsg_name(attr), "string");
 309                                 break;
 310                         case BLOBMSG_TYPE_ARRAY:
 311                                 blobmsg_add_string(data->buf, blobmsg_name(attr), "array");
 312                                 break;
 313                         case BLOBMSG_TYPE_TABLE:
 314                                 blobmsg_add_string(data->buf, blobmsg_name(attr), "object");
 315                                 break;
 316                         default:
 317                                 blobmsg_add_string(data->buf, blobmsg_name(attr), "unknown");
 318                                 break;
 319                         }
 320                 }
 321                 blobmsg_close_table(data->buf, t);
 322         }
 323         blobmsg_close_table(data->buf, o);
 324 }
 325
 326 static void uh_ubus_send_list(struct client *cl, json_object *obj, struct blob_attr *params)
 327 {
 328         struct blob_attr *cur, *dup;
 329         struct list_data data = { .buf = &cl->dispatch.ubus.buf, .verbose = false };
 330         void *r;
 331         int rem;
 332
 333         blob_buf_init(data.buf, 0);
 334
 335         uh_client_ref(cl);
 336
 337         if (!params || blob_id(params) != BLOBMSG_TYPE_ARRAY) {
 338                 r = blobmsg_open_array(data.buf, "result");
 339                 ubus_lookup(ctx, NULL, uh_ubus_list_cb, &data);
 340                 blobmsg_close_array(data.buf, r);
 341         }
 342         else {
 343                 r = blobmsg_open_table(data.buf, "result");
 344                 dup = blob_memdup(params);
 345                 if (dup)
 346                 {
 347                         rem = blobmsg_data_len(dup);
 348                         data.verbose = true;
 349                         __blob_for_each_attr(cur, blobmsg_data(dup), rem)
 350                                 ubus_lookup(ctx, blobmsg_data(cur), uh_ubus_list_cb, &data);
 351                         free(dup);
 352                 }
 353                 blobmsg_close_table(data.buf, r);
 354         }
 355
 356         uh_client_unref(cl);
 357
 358         uh_ubus_init_response(cl);
 359         blobmsg_add_blob(&buf, blob_data(data.buf->head));
 360         uh_ubus_send_response(cl);
 361 }
 362
 363 static bool parse_json_rpc(struct rpc_data *d, struct blob_attr *data)
 364 {
 365         const struct blobmsg_policy data_policy[] = {
 366                 { .type = BLOBMSG_TYPE_STRING },
 367                 { .type = BLOBMSG_TYPE_STRING },
 368                 { .type = BLOBMSG_TYPE_STRING },
 369                 { .type = BLOBMSG_TYPE_TABLE },
 370         };
 371         struct blob_attr *tb[__RPC_MAX];
 372         struct blob_attr *tb2[4];
 373         struct blob_attr *cur;
 374
 375         blobmsg_parse(rpc_policy, __RPC_MAX, tb, blob_data(data), blob_len(data));
 376
 377         cur = tb[RPC_JSONRPC];
 378         if (!cur || strcmp(blobmsg_data(cur), "2.0") != 0)
 379                 return false;
 380
 381         cur = tb[RPC_METHOD];
 382         if (!cur)
 383                 return false;
 384
 385         d->id = tb[RPC_ID];
 386         d->method = blobmsg_data(cur);
 387
 388         cur = tb[RPC_PARAMS];
 389         if (!cur)
 390                 return true;
 391
 392         d->params = blob_memdup(cur);
 393         if (!d->params)
 394                 return false;
 395
 396         blobmsg_parse_array(data_policy, ARRAY_SIZE(data_policy), tb2,
 397                             blobmsg_data(d->params), blobmsg_data_len(d->params));
 398
 399         if (tb2[0])
 400                 d->sid = blobmsg_data(tb2[0]);
 401
 402         if (conf.ubus_noauth && (!d->sid || !*d->sid))
 403                 d->sid = UH_UBUS_DEFAULT_SID;
 404
 405         if (tb2[1])
 406                 d->object = blobmsg_data(tb2[1]);
 407
 408         if (tb2[2])
 409                 d->function = blobmsg_data(tb2[2]);
 410
 411         d->data = tb2[3];
 412
 413         return true;
 414 }
 415
 416 static void uh_ubus_init_batch(struct client *cl)
 417 {
 418         struct dispatch_ubus *du = &cl->dispatch.ubus;
 419
 420         du->array = true;
 421         uh_ubus_send_header(cl);
 422         ops->chunk_printf(cl, "[\n\t");
 423 }
 424
 425 static void uh_ubus_complete_batch(struct client *cl)
 426 {
 427         ops->chunk_printf(cl, "\n]\n");
 428         ops->request_done(cl);
 429 }
 430
 431 static void uh_ubus_allowed_cb(struct ubus_request *req, int type, struct blob_attr *msg)
 432 {
 433         struct blob_attr *tb[__SES_MAX];
 434         bool *allow = (bool *)req->priv;
 435
 436         if (!msg)
 437                 return;
 438
 439         blobmsg_parse(ses_policy, __SES_MAX, tb, blob_data(msg), blob_len(msg));
 440
 441         if (tb[SES_ACCESS])
 442                 *allow = blobmsg_get_bool(tb[SES_ACCESS]);
 443 }
 444
 445 static bool uh_ubus_allowed(const char *sid, const char *obj, const char *fun)
 446 {
 447         uint32_t id;
 448         bool allow = false;
 449         static struct blob_buf req;
 450
 451         if (ubus_lookup_id(ctx, "session", &id))
 452                 return false;
 453
 454         blob_buf_init(&req, 0);
 455         blobmsg_add_string(&req, "ubus_rpc_session", sid);
 456         blobmsg_add_string(&req, "object", obj);
 457         blobmsg_add_string(&req, "function", fun);
 458
 459         ubus_invoke(ctx, id, "access", req.head, uh_ubus_allowed_cb, &allow, conf.script_timeout * 500);
 460
 461         return allow;
 462 }
 463
 464 static void uh_ubus_handle_request_object(struct client *cl, struct json_object *obj)
 465 {
 466         struct dispatch_ubus *du = &cl->dispatch.ubus;
 467         struct rpc_data data = {};
 468         enum rpc_error err = ERROR_PARSE;
 469
 470         uh_client_ref(cl);
 471
 472         if (json_object_get_type(obj) != json_type_object)
 473                 goto error;
 474
 475         du->jsobj_cur = obj;
 476         blob_buf_init(&buf, 0);
 477         if (!blobmsg_add_object(&buf, obj))
 478                 goto error;
 479
 480         if (!parse_json_rpc(&data, buf.head))
 481                 goto error;
 482
 483         if (!strcmp(data.method, "call")) {
 484                 if (!data.sid || !data.object || !data.function || !data.data)
 485                         goto error;
 486
 487                 du->func = data.function;
 488                 if (ubus_lookup_id(ctx, data.object, &du->obj)) {
 489                         err = ERROR_OBJECT;
 490                         goto error;
 491                 }
 492
 493                 if (!conf.ubus_noauth && !uh_ubus_allowed(data.sid, data.object, data.function)) {
 494                         err = ERROR_ACCESS;
 495                         goto error;
 496                 }
 497
 498                 uh_ubus_send_request(cl, obj, data.sid, data.data);
 499                 goto out;
 500         }
 501         else if (!strcmp(data.method, "list")) {
 502                 uh_ubus_send_list(cl, obj, data.params);
 503                 goto out;
 504         }
 505         else {
 506                 err = ERROR_METHOD;
 507                 goto error;
 508         }
 509
 510 error:
 511         uh_ubus_json_error(cl, err);
 512 out:
 513         if (data.params)
 514                 free(data.params);
 515
 516         uh_client_unref(cl);
 517 }
 518
 519 static void __uh_ubus_next_batched_request(struct uloop_timeout *timeout)
 520 {
 521         struct dispatch_ubus *du = container_of(timeout, struct dispatch_ubus, timeout);
 522         struct client *cl = container_of(du, struct client, dispatch.ubus);
 523         struct json_object *obj = du->jsobj;
 524         int len;
 525
 526         len = json_object_array_length(obj);
 527         if (du->array_idx >= len)
 528                 return uh_ubus_complete_batch(cl);
 529
 530         obj = json_object_array_get_idx(obj, du->array_idx++);
 531         uh_ubus_handle_request_object(cl, obj);
 532 }
 533
 534 static void uh_ubus_data_done(struct client *cl)
 535 {
 536         struct dispatch_ubus *du = &cl->dispatch.ubus;
 537         struct json_object *obj = du->jsobj;
 538
 539         switch (obj ? json_object_get_type(obj) : json_type_null) {
 540         case json_type_object:
 541                 uh_ubus_send_header(cl);
 542                 return uh_ubus_handle_request_object(cl, obj);
 543         case json_type_array:
 544                 uh_ubus_init_batch(cl);
 545                 return uh_ubus_next_batched_request(cl);
 546         default:
 547                 return uh_ubus_single_error(cl, ERROR_PARSE);
 548         }
 549 }
 550
 551 static int uh_ubus_data_send(struct client *cl, const char *data, int len)
 552 {
 553         struct dispatch_ubus *du = &cl->dispatch.ubus;
 554
 555         if (du->jsobj || !du->jstok)
 556                 goto error;
 557
 558         du->post_len += len;
 559         if (du->post_len > UH_UBUS_MAX_POST_SIZE)
 560                 goto error;
 561
 562         du->jsobj = json_tokener_parse_ex(du->jstok, data, len);
 563         return len;
 564
 565 error:
 566         uh_ubus_single_error(cl, ERROR_PARSE);
 567         return 0;
 568 }
 569
 570 static void uh_ubus_handle_request(struct client *cl, char *url, struct path_info *pi)
 571 {
 572         struct dispatch *d = &cl->dispatch;
 573
 574         blob_buf_init(&buf, 0);
 575
 576         if (cl->request.method != UH_HTTP_MSG_POST)
 577                 return ops->client_error(cl, 400, "Bad Request", "Invalid Request");
 578
 579         d->close_fds = uh_ubus_close_fds;
 580         d->free = uh_ubus_request_free;
 581         d->data_send = uh_ubus_data_send;
 582         d->data_done = uh_ubus_data_done;
 583         d->ubus.jstok = json_tokener_new();
 584 }
 585
 586 static bool
 587 uh_ubus_check_url(const char *url)
 588 {
 589         return ops->path_match(conf.ubus_prefix, url);
 590 }
 591
 592 static int
 593 uh_ubus_init(void)
 594 {
 595         static struct dispatch_handler ubus_dispatch = {
 596                 .check_url = uh_ubus_check_url,
 597                 .handle_request = uh_ubus_handle_request,
 598         };
 599
 600         ctx = ubus_connect(conf.ubus_socket);
 601         if (!ctx) {
 602                 fprintf(stderr, "Unable to connect to ubus socket\n");
 603                 exit(1);
 604         }
 605
 606         ops->dispatch_add(&ubus_dispatch);
 607
 608         uloop_done();
 609         return 0;
 610 }
 611
 612
 613 static int uh_ubus_plugin_init(const struct uhttpd_ops *o, struct config *c)
 614 {
 615         ops = o;
 616         _conf = c;
 617         return uh_ubus_init();
 618 }
 619
 620 static void uh_ubus_post_init(void)
 621 {
 622         ubus_add_uloop(ctx);
 623 }
 624
 625 const struct uhttpd_plugin uhttpd_plugin = {
 626         .init = uh_ubus_plugin_init,
 627         .post_init = uh_ubus_post_init,
 628 };