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