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