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(buf.head, true);
 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                 return ops->request_done(cl);
 141 }
 142
 143 static void uh_ubus_init_response(struct client *cl)
 144 {
 145         struct dispatch_ubus *du = &cl->dispatch.ubus;
 146         struct json_object *obj = du->jsobj_cur;
 147
 148         blob_buf_init(&buf, 0);
 149         blobmsg_add_string(&buf, "jsonrpc", "2.0");
 150
 151         if (obj)
 152                 obj = json_object_object_get(obj, "id");
 153
 154         if (obj)
 155                 blobmsg_add_json_element(&buf, "id", obj);
 156         else
 157                 blobmsg_add_field(&buf, BLOBMSG_TYPE_UNSPEC, "id", NULL, 0);
 158 }
 159
 160 static void uh_ubus_json_error(struct client *cl, enum rpc_error type)
 161 {
 162         void *c;
 163
 164         uh_ubus_init_response(cl);
 165         c = blobmsg_open_table(&buf, "error");
 166         blobmsg_add_u32(&buf, "code", json_errors[type].code);
 167         blobmsg_add_string(&buf, "message", json_errors[type].msg);
 168         blobmsg_close_table(&buf, c);
 169         uh_ubus_send_response(cl);
 170 }
 171
 172 static void
 173 uh_ubus_request_data_cb(struct ubus_request *req, int type, struct blob_attr *msg)
 174 {
 175         struct dispatch_ubus *du = container_of(req, struct dispatch_ubus, req);
 176
 177         blobmsg_add_field(&du->buf, BLOBMSG_TYPE_TABLE, "", blob_data(msg), blob_len(msg));
 178 }
 179
 180 static void
 181 uh_ubus_request_cb(struct ubus_request *req, int ret)
 182 {
 183         struct dispatch_ubus *du = container_of(req, struct dispatch_ubus, req);
 184         struct client *cl = container_of(du, struct client, dispatch.ubus);
 185         struct blob_attr *cur;
 186         void *r;
 187         int rem;
 188
 189         uloop_timeout_cancel(&du->timeout);
 190         uh_ubus_init_response(cl);
 191         r = blobmsg_open_array(&buf, "result");
 192         blobmsg_add_u32(&buf, "", ret);
 193         blob_for_each_attr(cur, du->buf.head, rem)
 194                 blobmsg_add_blob(&buf, cur);
 195         blobmsg_close_array(&buf, r);
 196         uh_ubus_send_response(cl);
 197 }
 198
 199 static void
 200 uh_ubus_timeout_cb(struct uloop_timeout *timeout)
 201 {
 202         struct dispatch_ubus *du = container_of(timeout, struct dispatch_ubus, timeout);
 203         struct client *cl = container_of(du, struct client, dispatch.ubus);
 204
 205         ubus_abort_request(ctx, &du->req);
 206         uh_ubus_json_error(cl, ERROR_TIMEOUT);
 207 }
 208
 209 static void uh_ubus_close_fds(struct client *cl)
 210 {
 211         if (ctx->sock.fd < 0)
 212                 return;
 213
 214         close(ctx->sock.fd);
 215         ctx->sock.fd = -1;
 216 }
 217
 218 static void uh_ubus_request_free(struct client *cl)
 219 {
 220         struct dispatch_ubus *du = &cl->dispatch.ubus;
 221
 222         blob_buf_free(&du->buf);
 223         uloop_timeout_cancel(&du->timeout);
 224
 225         if (du->jsobj)
 226                 json_object_put(du->jsobj);
 227
 228         if (du->jstok)
 229                 json_tokener_free(du->jstok);
 230
 231         if (du->req_pending)
 232                 ubus_abort_request(ctx, &du->req);
 233 }
 234
 235 static void uh_ubus_single_error(struct client *cl, enum rpc_error type)
 236 {
 237         uh_ubus_send_header(cl);
 238         uh_ubus_json_error(cl, type);
 239         ops->request_done(cl);
 240 }
 241
 242 static void uh_ubus_send_request(struct client *cl, json_object *obj, const char *sid, struct blob_attr *args)
 243 {
 244         struct dispatch *d = &cl->dispatch;
 245         struct dispatch_ubus *du = &d->ubus;
 246         struct blob_attr *cur;
 247         static struct blob_buf req;
 248         int ret, rem;
 249
 250         blob_buf_init(&req, 0);
 251         blobmsg_for_each_attr(cur, args, rem) {
 252                 if (!strcmp(blobmsg_name(cur), "ubus_rpc_session"))
 253                         return uh_ubus_json_error(cl, ERROR_PARAMS);
 254                 blobmsg_add_blob(&req, cur);
 255         }
 256
 257         blobmsg_add_string(&req, "ubus_rpc_session", sid);
 258
 259         blob_buf_init(&du->buf, 0);
 260         memset(&du->req, 0, sizeof(du->req));
 261         ret = ubus_invoke_async(ctx, du->obj, du->func, req.head, &du->req);
 262         if (ret)
 263                 return uh_ubus_json_error(cl, ERROR_INTERNAL);
 264
 265         du->req.data_cb = uh_ubus_request_data_cb;
 266         du->req.complete_cb = uh_ubus_request_cb;
 267         ubus_complete_request_async(ctx, &du->req);
 268
 269         du->timeout.cb = uh_ubus_timeout_cb;
 270         uloop_timeout_set(&du->timeout, conf.script_timeout * 1000);
 271
 272         du->req_pending = true;
 273 }
 274
 275 static void uh_ubus_list_cb(struct ubus_context *ctx, struct ubus_object_data *obj, void *priv)
 276 {
 277         struct blob_attr *sig, *attr;
 278         struct list_data *data = priv;
 279         int rem, rem2;
 280         void *t, *o;
 281
 282         if (!data->verbose) {
 283                 blobmsg_add_string(data->buf, NULL, obj->path);
 284                 return;
 285         }
 286
 287         if (!obj->signature)
 288                 return;
 289
 290         o = blobmsg_open_table(data->buf, obj->path);
 291         blob_for_each_attr(sig, obj->signature, rem) {
 292                 t = blobmsg_open_table(data->buf, blobmsg_name(sig));
 293                 rem2 = blobmsg_data_len(sig);
 294                 __blob_for_each_attr(attr, blobmsg_data(sig), rem2) {
 295                         if (blob_id(attr) != BLOBMSG_TYPE_INT32)
 296                                 continue;
 297
 298                         switch (blobmsg_get_u32(attr)) {
 299                         case BLOBMSG_TYPE_INT8:
 300                                 blobmsg_add_string(data->buf, blobmsg_name(attr), "boolean");
 301                                 break;
 302                         case BLOBMSG_TYPE_INT32:
 303                                 blobmsg_add_string(data->buf, blobmsg_name(attr), "number");
 304                                 break;
 305                         case BLOBMSG_TYPE_STRING:
 306                                 blobmsg_add_string(data->buf, blobmsg_name(attr), "string");
 307                                 break;
 308                         case BLOBMSG_TYPE_ARRAY:
 309                                 blobmsg_add_string(data->buf, blobmsg_name(attr), "array");
 310                                 break;
 311                         case BLOBMSG_TYPE_TABLE:
 312                                 blobmsg_add_string(data->buf, blobmsg_name(attr), "object");
 313                                 break;
 314                         default:
 315                                 blobmsg_add_string(data->buf, blobmsg_name(attr), "unknown");
 316                                 break;
 317                         }
 318                 }
 319                 blobmsg_close_table(data->buf, t);
 320         }
 321         blobmsg_close_table(data->buf, o);
 322 }
 323
 324 static void uh_ubus_send_list(struct client *cl, json_object *obj, struct blob_attr *params)
 325 {
 326         struct blob_attr *cur, *dup;
 327         struct list_data data = { .buf = &cl->dispatch.ubus.buf, .verbose = false };
 328         void *r;
 329         int rem;
 330
 331         blob_buf_init(data.buf, 0);
 332
 333         uh_client_ref(cl);
 334
 335         if (!params || blob_id(params) != BLOBMSG_TYPE_ARRAY) {
 336                 r = blobmsg_open_array(data.buf, "result");
 337                 ubus_lookup(ctx, NULL, uh_ubus_list_cb, &data);
 338                 blobmsg_close_array(data.buf, r);
 339         }
 340         else {
 341                 r = blobmsg_open_table(data.buf, "result");
 342                 dup = blob_memdup(params);
 343                 if (dup)
 344                 {
 345                         rem = blobmsg_data_len(dup);
 346                         data.verbose = true;
 347                         __blob_for_each_attr(cur, blobmsg_data(dup), rem)
 348                                 ubus_lookup(ctx, blobmsg_data(cur), uh_ubus_list_cb, &data);
 349                         free(dup);
 350                 }
 351                 blobmsg_close_table(data.buf, r);
 352         }
 353
 354         uh_client_unref(cl);
 355
 356         uh_ubus_init_response(cl);
 357         blobmsg_add_blob(&buf, blob_data(data.buf->head));
 358         uh_ubus_send_response(cl);
 359 }
 360
 361 static bool parse_json_rpc(struct rpc_data *d, struct blob_attr *data)
 362 {
 363         const struct blobmsg_policy data_policy[] = {
 364                 { .type = BLOBMSG_TYPE_STRING },
 365                 { .type = BLOBMSG_TYPE_STRING },
 366                 { .type = BLOBMSG_TYPE_STRING },
 367                 { .type = BLOBMSG_TYPE_TABLE },
 368         };
 369         struct blob_attr *tb[__RPC_MAX];
 370         struct blob_attr *tb2[4];
 371         struct blob_attr *cur;
 372
 373         blobmsg_parse(rpc_policy, __RPC_MAX, tb, blob_data(data), blob_len(data));
 374
 375         cur = tb[RPC_JSONRPC];
 376         if (!cur || strcmp(blobmsg_data(cur), "2.0") != 0)
 377                 return false;
 378
 379         cur = tb[RPC_METHOD];
 380         if (!cur)
 381                 return false;
 382
 383         d->id = tb[RPC_ID];
 384         d->method = blobmsg_data(cur);
 385
 386         cur = tb[RPC_PARAMS];
 387         if (!cur)
 388                 return true;
 389
 390         d->params = blob_memdup(cur);
 391         if (!d->params)
 392                 return false;
 393
 394         blobmsg_parse_array(data_policy, ARRAY_SIZE(data_policy), tb2,
 395                             blobmsg_data(d->params), blobmsg_data_len(d->params));
 396
 397         if (tb2[0])
 398                 d->sid = blobmsg_data(tb2[0]);
 399
 400         if (conf.ubus_noauth && (!d->sid || !*d->sid))
 401                 d->sid = UH_UBUS_DEFAULT_SID;
 402
 403         if (tb2[1])
 404                 d->object = blobmsg_data(tb2[1]);
 405
 406         if (tb2[2])
 407                 d->function = blobmsg_data(tb2[2]);
 408
 409         d->data = tb2[3];
 410
 411         return true;
 412 }
 413
 414 static void uh_ubus_init_batch(struct client *cl)
 415 {
 416         struct dispatch_ubus *du = &cl->dispatch.ubus;
 417
 418         du->array = true;
 419         uh_ubus_send_header(cl);
 420         ops->chunk_printf(cl, "[");
 421 }
 422
 423 static void uh_ubus_complete_batch(struct client *cl)
 424 {
 425         ops->chunk_printf(cl, "]");
 426         ops->request_done(cl);
 427 }
 428
 429 static void uh_ubus_allowed_cb(struct ubus_request *req, int type, struct blob_attr *msg)
 430 {
 431         struct blob_attr *tb[__SES_MAX];
 432         bool *allow = (bool *)req->priv;
 433
 434         if (!msg)
 435                 return;
 436
 437         blobmsg_parse(ses_policy, __SES_MAX, tb, blob_data(msg), blob_len(msg));
 438
 439         if (tb[SES_ACCESS])
 440                 *allow = blobmsg_get_bool(tb[SES_ACCESS]);
 441 }
 442
 443 static bool uh_ubus_allowed(const char *sid, const char *obj, const char *fun)
 444 {
 445         uint32_t id;
 446         bool allow = false;
 447         static struct blob_buf req;
 448
 449         if (ubus_lookup_id(ctx, "session", &id))
 450                 return false;
 451
 452         blob_buf_init(&req, 0);
 453         blobmsg_add_string(&req, "ubus_rpc_session", sid);
 454         blobmsg_add_string(&req, "object", obj);
 455         blobmsg_add_string(&req, "function", fun);
 456
 457         ubus_invoke(ctx, id, "access", req.head, uh_ubus_allowed_cb, &allow, conf.script_timeout * 500);
 458
 459         return allow;
 460 }
 461
 462 static void uh_ubus_handle_request_object(struct client *cl, struct json_object *obj)
 463 {
 464         struct dispatch_ubus *du = &cl->dispatch.ubus;
 465         struct rpc_data data = {};
 466         enum rpc_error err = ERROR_PARSE;
 467
 468         uh_client_ref(cl);
 469
 470         if (json_object_get_type(obj) != json_type_object)
 471                 goto error;
 472
 473         du->jsobj_cur = obj;
 474         blob_buf_init(&buf, 0);
 475         if (!blobmsg_add_object(&buf, obj))
 476                 goto error;
 477
 478         if (!parse_json_rpc(&data, buf.head))
 479                 goto error;
 480
 481         if (!strcmp(data.method, "call")) {
 482                 if (!data.sid || !data.object || !data.function || !data.data)
 483                         goto error;
 484
 485                 du->func = data.function;
 486                 if (ubus_lookup_id(ctx, data.object, &du->obj)) {
 487                         err = ERROR_OBJECT;
 488                         goto error;
 489                 }
 490
 491                 if (!conf.ubus_noauth && !uh_ubus_allowed(data.sid, data.object, data.function)) {
 492                         err = ERROR_ACCESS;
 493                         goto error;
 494                 }
 495
 496                 uh_ubus_send_request(cl, obj, data.sid, data.data);
 497                 goto out;
 498         }
 499         else if (!strcmp(data.method, "list")) {
 500                 uh_ubus_send_list(cl, obj, data.params);
 501                 goto out;
 502         }
 503         else {
 504                 err = ERROR_METHOD;
 505                 goto error;
 506         }
 507
 508 error:
 509         uh_ubus_json_error(cl, err);
 510 out:
 511         if (data.params)
 512                 free(data.params);
 513
 514         uh_client_unref(cl);
 515 }
 516
 517 static void __uh_ubus_next_batched_request(struct uloop_timeout *timeout)
 518 {
 519         struct dispatch_ubus *du = container_of(timeout, struct dispatch_ubus, timeout);
 520         struct client *cl = container_of(du, struct client, dispatch.ubus);
 521         struct json_object *obj = du->jsobj;
 522         int len;
 523
 524         len = json_object_array_length(obj);
 525         if (du->array_idx >= len)
 526                 return uh_ubus_complete_batch(cl);
 527
 528         obj = json_object_array_get_idx(obj, du->array_idx++);
 529         uh_ubus_handle_request_object(cl, obj);
 530 }
 531
 532 static void uh_ubus_data_done(struct client *cl)
 533 {
 534         struct dispatch_ubus *du = &cl->dispatch.ubus;
 535         struct json_object *obj = du->jsobj;
 536
 537         switch (obj ? json_object_get_type(obj) : json_type_null) {
 538         case json_type_object:
 539                 uh_ubus_send_header(cl);
 540                 return uh_ubus_handle_request_object(cl, obj);
 541         case json_type_array:
 542                 uh_ubus_init_batch(cl);
 543                 return uh_ubus_next_batched_request(cl);
 544         default:
 545                 return uh_ubus_single_error(cl, ERROR_PARSE);
 546         }
 547 }
 548
 549 static int uh_ubus_data_send(struct client *cl, const char *data, int len)
 550 {
 551         struct dispatch_ubus *du = &cl->dispatch.ubus;
 552
 553         if (du->jsobj || !du->jstok)
 554                 goto error;
 555
 556         du->post_len += len;
 557         if (du->post_len > UH_UBUS_MAX_POST_SIZE)
 558                 goto error;
 559
 560         du->jsobj = json_tokener_parse_ex(du->jstok, data, len);
 561         return len;
 562
 563 error:
 564         uh_ubus_single_error(cl, ERROR_PARSE);
 565         return 0;
 566 }
 567
 568 static void uh_ubus_handle_request(struct client *cl, char *url, struct path_info *pi)
 569 {
 570         struct dispatch *d = &cl->dispatch;
 571
 572         blob_buf_init(&buf, 0);
 573
 574         if (cl->request.method != UH_HTTP_MSG_POST)
 575                 return ops->client_error(cl, 400, "Bad Request", "Invalid Request");
 576
 577         d->close_fds = uh_ubus_close_fds;
 578         d->free = uh_ubus_request_free;
 579         d->data_send = uh_ubus_data_send;
 580         d->data_done = uh_ubus_data_done;
 581         d->ubus.jstok = json_tokener_new();
 582 }
 583
 584 static bool
 585 uh_ubus_check_url(const char *url)
 586 {
 587         return ops->path_match(conf.ubus_prefix, url);
 588 }
 589
 590 static int
 591 uh_ubus_init(void)
 592 {
 593         static struct dispatch_handler ubus_dispatch = {
 594                 .check_url = uh_ubus_check_url,
 595                 .handle_request = uh_ubus_handle_request,
 596         };
 597
 598         ctx = ubus_connect(conf.ubus_socket);
 599         if (!ctx) {
 600                 fprintf(stderr, "Unable to connect to ubus socket\n");
 601                 exit(1);
 602         }
 603
 604         ops->dispatch_add(&ubus_dispatch);
 605
 606         uloop_done();
 607         return 0;
 608 }
 609
 610
 611 static int uh_ubus_plugin_init(const struct uhttpd_ops *o, struct config *c)
 612 {
 613         ops = o;
 614         _conf = c;
 615         return uh_ubus_init();
 616 }
 617
 618 static void uh_ubus_post_init(void)
 619 {
 620         ubus_add_uloop(ctx);
 621 }
 622
 623 const struct uhttpd_plugin uhttpd_plugin = {
 624         .init = uh_ubus_plugin_init,
 625         .post_init = uh_ubus_post_init,
 626 };