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 = cur;
 372
 373         blobmsg_parse_array(data_policy, ARRAY_SIZE(data_policy), tb2,
 374                             blobmsg_data(cur), blobmsg_data_len(cur));
 375
 376         if (tb2[0])
 377                 d->object = blobmsg_data(tb2[0]);
 378
 379         if (tb2[1])
 380                 d->function = blobmsg_data(tb2[1]);
 381
 382         d->data = tb2[2];
 383
 384         return true;
 385 }
 386
 387 static void uh_ubus_init_batch(struct client *cl)
 388 {
 389         struct dispatch_ubus *du = &cl->dispatch.ubus;
 390
 391         du->array = true;
 392         uh_ubus_send_header(cl);
 393         ops->chunk_printf(cl, "[\n\t");
 394 }
 395
 396 static void uh_ubus_complete_batch(struct client *cl)
 397 {
 398         ops->chunk_printf(cl, "\n]\n");
 399         ops->request_done(cl);
 400 }
 401
 402 static void uh_ubus_allowed_cb(struct ubus_request *req, int type, struct blob_attr *msg)
 403 {
 404         struct blob_attr *tb[__SES_MAX];
 405         bool *allow = (bool *)req->priv;
 406
 407         if (!msg)
 408                 return;
 409
 410         blobmsg_parse(ses_policy, __SES_MAX, tb, blob_data(msg), blob_len(msg));
 411
 412         if (tb[SES_ACCESS])
 413                 *allow = blobmsg_get_bool(tb[SES_ACCESS]);
 414 }
 415
 416 static bool uh_ubus_allowed(const char *sid, const char *obj, const char *fun)
 417 {
 418         uint32_t id;
 419         bool allow = false;
 420         static struct blob_buf req;
 421
 422         if (ubus_lookup_id(ctx, "session", &id))
 423                 return false;
 424
 425         blob_buf_init(&req, 0);
 426         blobmsg_add_string(&req, "sid", sid);
 427         blobmsg_add_string(&req, "object", obj);
 428         blobmsg_add_string(&req, "function", fun);
 429
 430         ubus_invoke(ctx, id, "access", req.head, uh_ubus_allowed_cb, &allow, 250);
 431
 432         return allow;
 433 }
 434
 435 static void uh_ubus_handle_request_object(struct client *cl, struct json_object *obj)
 436 {
 437         struct dispatch_ubus *du = &cl->dispatch.ubus;
 438         struct rpc_data data = {};
 439         enum rpc_error err = ERROR_PARSE;
 440
 441         if (json_object_get_type(obj) != json_type_object)
 442                 goto error;
 443
 444         du->jsobj_cur = obj;
 445         blob_buf_init(&buf, 0);
 446         if (!blobmsg_add_object(&buf, obj))
 447                 goto error;
 448
 449         if (!parse_json_rpc(&data, buf.head))
 450                 goto error;
 451
 452         if (!strcmp(data.method, "call")) {
 453                 if (!data.object || !data.function || !data.data)
 454                         goto error;
 455
 456                 du->func = data.function;
 457                 if (ubus_lookup_id(ctx, data.object, &du->obj)) {
 458                         err = ERROR_OBJECT;
 459                         goto error;
 460                 }
 461
 462                 if (!conf.ubus_noauth && !uh_ubus_allowed(du->sid, data.object, data.function)) {
 463                         err = ERROR_ACCESS;
 464                         goto error;
 465                 }
 466
 467                 uh_ubus_send_request(cl, obj, data.data);
 468                 return;
 469         }
 470         else if (!strcmp(data.method, "list")) {
 471                 uh_ubus_send_list(cl, obj, data.params);
 472                 return;
 473         }
 474         else {
 475                 err = ERROR_METHOD;
 476                 goto error;
 477         }
 478
 479 error:
 480         uh_ubus_json_error(cl, err);
 481 }
 482
 483 static void __uh_ubus_next_batched_request(struct uloop_timeout *timeout)
 484 {
 485         struct dispatch_ubus *du = container_of(timeout, struct dispatch_ubus, timeout);
 486         struct client *cl = container_of(du, struct client, dispatch.ubus);
 487         struct json_object *obj = du->jsobj;
 488         int len;
 489
 490         len = json_object_array_length(obj);
 491         if (du->array_idx >= len)
 492                 return uh_ubus_complete_batch(cl);
 493
 494         obj = json_object_array_get_idx(obj, du->array_idx++);
 495         uh_ubus_handle_request_object(cl, obj);
 496 }
 497
 498 static void uh_ubus_data_done(struct client *cl)
 499 {
 500         struct dispatch_ubus *du = &cl->dispatch.ubus;
 501         struct json_object *obj = du->jsobj;
 502
 503         switch (obj ? json_object_get_type(obj) : json_type_null) {
 504         case json_type_object:
 505                 uh_ubus_send_header(cl);
 506                 return uh_ubus_handle_request_object(cl, obj);
 507         case json_type_array:
 508                 uh_ubus_init_batch(cl);
 509                 if (json_object_array_length(obj) > 0)
 510                         return uh_ubus_next_batched_request(cl);
 511                 /* fall through */
 512         default:
 513                 return uh_ubus_single_error(cl, ERROR_PARSE);
 514         }
 515 }
 516
 517 static int uh_ubus_data_send(struct client *cl, const char *data, int len)
 518 {
 519         struct dispatch_ubus *du = &cl->dispatch.ubus;
 520
 521         if (du->jsobj || !du->jstok)
 522                 goto error;
 523
 524         du->post_len += len;
 525         if (du->post_len > UH_UBUS_MAX_POST_SIZE)
 526                 goto error;
 527
 528         du->jsobj = json_tokener_parse_ex(du->jstok, data, len);
 529         return len;
 530
 531 error:
 532         uh_ubus_single_error(cl, ERROR_PARSE);
 533         return 0;
 534 }
 535
 536 static void uh_ubus_handle_request(struct client *cl, char *url, struct path_info *pi)
 537 {
 538         struct dispatch *d = &cl->dispatch;
 539         char *sid, *sep;
 540
 541         blob_buf_init(&buf, 0);
 542
 543         if (conf.ubus_noauth) {
 544                 sid = UH_UBUS_DEFAULT_SID;
 545         }
 546         else {
 547                 url += strlen(conf.ubus_prefix);
 548                 while (*url == '/')
 549                         url++;
 550
 551                 sep = strchr(url, '/');
 552                 if (sep)
 553                         *sep = 0;
 554
 555                 sid = url;
 556         }
 557
 558         if (strlen(sid) != 32 ||
 559             cl->request.method != UH_HTTP_MSG_POST)
 560                 return ops->client_error(cl, 400, "Bad Request", "Invalid Request");
 561
 562         d->close_fds = uh_ubus_close_fds;
 563         d->free = uh_ubus_request_free;
 564         d->data_send = uh_ubus_data_send;
 565         d->data_done = uh_ubus_data_done;
 566         d->ubus.jstok = json_tokener_new();
 567         d->ubus.sid = sid;
 568 }
 569
 570 static bool
 571 uh_ubus_check_url(const char *url)
 572 {
 573         return ops->path_match(conf.ubus_prefix, url);
 574 }
 575
 576 static int
 577 uh_ubus_init(void)
 578 {
 579         static struct dispatch_handler ubus_dispatch = {
 580                 .check_url = uh_ubus_check_url,
 581                 .handle_request = uh_ubus_handle_request,
 582         };
 583
 584         ctx = ubus_connect(conf.ubus_socket);
 585         if (!ctx) {
 586                 fprintf(stderr, "Unable to connect to ubus socket\n");
 587                 exit(1);
 588         }
 589
 590         ops->dispatch_add(&ubus_dispatch);
 591
 592         uloop_done();
 593         return 0;
 594 }
 595
 596
 597 static int uh_ubus_plugin_init(const struct uhttpd_ops *o, struct config *c)
 598 {
 599         ops = o;
 600         _conf = c;
 601         return uh_ubus_init();
 602 }
 603
 604 static void uh_ubus_post_init(void)
 605 {
 606         ubus_add_uloop(ctx);
 607 }
 608
 609 const struct uhttpd_plugin uhttpd_plugin = {
 610         .init = uh_ubus_plugin_init,
 611         .post_init = uh_ubus_post_init,
 612 };