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         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_ubus_init_response(cl);
 355         blobmsg_add_blob(&buf, blob_data(data.buf->head));
 356         uh_ubus_send_response(cl);
 357 }
 358
 359 static bool parse_json_rpc(struct rpc_data *d, struct blob_attr *data)
 360 {
 361         const struct blobmsg_policy data_policy[] = {
 362                 { .type = BLOBMSG_TYPE_STRING },
 363                 { .type = BLOBMSG_TYPE_STRING },
 364                 { .type = BLOBMSG_TYPE_STRING },
 365                 { .type = BLOBMSG_TYPE_TABLE },
 366         };
 367         struct blob_attr *tb[__RPC_MAX];
 368         struct blob_attr *tb2[4];
 369         struct blob_attr *cur;
 370
 371         blobmsg_parse(rpc_policy, __RPC_MAX, tb, blob_data(data), blob_len(data));
 372
 373         cur = tb[RPC_JSONRPC];
 374         if (!cur || strcmp(blobmsg_data(cur), "2.0") != 0)
 375                 return false;
 376
 377         cur = tb[RPC_METHOD];
 378         if (!cur)
 379                 return false;
 380
 381         d->id = tb[RPC_ID];
 382         d->method = blobmsg_data(cur);
 383
 384         cur = tb[RPC_PARAMS];
 385         if (!cur)
 386                 return true;
 387
 388         d->params = blob_memdup(cur);
 389         if (!d->params)
 390                 return false;
 391
 392         blobmsg_parse_array(data_policy, ARRAY_SIZE(data_policy), tb2,
 393                             blobmsg_data(d->params), blobmsg_data_len(d->params));
 394
 395         if (tb2[0])
 396                 d->sid = blobmsg_data(tb2[0]);
 397
 398         if (conf.ubus_noauth && (!d->sid || !*d->sid))
 399                 d->sid = UH_UBUS_DEFAULT_SID;
 400
 401         if (tb2[1])
 402                 d->object = blobmsg_data(tb2[1]);
 403
 404         if (tb2[2])
 405                 d->function = blobmsg_data(tb2[2]);
 406
 407         d->data = tb2[3];
 408
 409         return true;
 410 }
 411
 412 static void uh_ubus_init_batch(struct client *cl)
 413 {
 414         struct dispatch_ubus *du = &cl->dispatch.ubus;
 415
 416         du->array = true;
 417         uh_ubus_send_header(cl);
 418         ops->chunk_printf(cl, "[\n\t");
 419 }
 420
 421 static void uh_ubus_complete_batch(struct client *cl)
 422 {
 423         ops->chunk_printf(cl, "\n]\n");
 424         ops->request_done(cl);
 425 }
 426
 427 static void uh_ubus_allowed_cb(struct ubus_request *req, int type, struct blob_attr *msg)
 428 {
 429         struct blob_attr *tb[__SES_MAX];
 430         bool *allow = (bool *)req->priv;
 431
 432         if (!msg)
 433                 return;
 434
 435         blobmsg_parse(ses_policy, __SES_MAX, tb, blob_data(msg), blob_len(msg));
 436
 437         if (tb[SES_ACCESS])
 438                 *allow = blobmsg_get_bool(tb[SES_ACCESS]);
 439 }
 440
 441 static bool uh_ubus_allowed(const char *sid, const char *obj, const char *fun)
 442 {
 443         uint32_t id;
 444         bool allow = false;
 445         static struct blob_buf req;
 446
 447         if (ubus_lookup_id(ctx, "session", &id))
 448                 return false;
 449
 450         blob_buf_init(&req, 0);
 451         blobmsg_add_string(&req, "ubus_rpc_session", sid);
 452         blobmsg_add_string(&req, "object", obj);
 453         blobmsg_add_string(&req, "function", fun);
 454
 455         ubus_invoke(ctx, id, "access", req.head, uh_ubus_allowed_cb, &allow, conf.script_timeout * 500);
 456
 457         return allow;
 458 }
 459
 460 static void uh_ubus_handle_request_object(struct client *cl, struct json_object *obj)
 461 {
 462         struct dispatch_ubus *du = &cl->dispatch.ubus;
 463         struct rpc_data data = {};
 464         enum rpc_error err = ERROR_PARSE;
 465
 466         if (json_object_get_type(obj) != json_type_object)
 467                 goto error;
 468
 469         du->jsobj_cur = obj;
 470         blob_buf_init(&buf, 0);
 471         if (!blobmsg_add_object(&buf, obj))
 472                 goto error;
 473
 474         if (!parse_json_rpc(&data, buf.head))
 475                 goto error;
 476
 477         if (!strcmp(data.method, "call")) {
 478                 if (!data.sid || !data.object || !data.function || !data.data)
 479                         goto error;
 480
 481                 du->func = data.function;
 482                 if (ubus_lookup_id(ctx, data.object, &du->obj)) {
 483                         err = ERROR_OBJECT;
 484                         goto error;
 485                 }
 486
 487                 if (!conf.ubus_noauth && !uh_ubus_allowed(data.sid, data.object, data.function)) {
 488                         err = ERROR_ACCESS;
 489                         goto error;
 490                 }
 491
 492                 uh_ubus_send_request(cl, obj, data.sid, data.data);
 493                 goto out;
 494         }
 495         else if (!strcmp(data.method, "list")) {
 496                 uh_ubus_send_list(cl, obj, data.params);
 497                 goto out;
 498         }
 499         else {
 500                 err = ERROR_METHOD;
 501                 goto error;
 502         }
 503
 504 error:
 505         uh_ubus_json_error(cl, err);
 506 out:
 507         if (data.params)
 508                 free(data.params);
 509 }
 510
 511 static void __uh_ubus_next_batched_request(struct uloop_timeout *timeout)
 512 {
 513         struct dispatch_ubus *du = container_of(timeout, struct dispatch_ubus, timeout);
 514         struct client *cl = container_of(du, struct client, dispatch.ubus);
 515         struct json_object *obj = du->jsobj;
 516         int len;
 517
 518         len = json_object_array_length(obj);
 519         if (du->array_idx >= len)
 520                 return uh_ubus_complete_batch(cl);
 521
 522         obj = json_object_array_get_idx(obj, du->array_idx++);
 523         uh_ubus_handle_request_object(cl, obj);
 524 }
 525
 526 static void uh_ubus_data_done(struct client *cl)
 527 {
 528         struct dispatch_ubus *du = &cl->dispatch.ubus;
 529         struct json_object *obj = du->jsobj;
 530
 531         switch (obj ? json_object_get_type(obj) : json_type_null) {
 532         case json_type_object:
 533                 uh_ubus_send_header(cl);
 534                 return uh_ubus_handle_request_object(cl, obj);
 535         case json_type_array:
 536                 uh_ubus_init_batch(cl);
 537                 return uh_ubus_next_batched_request(cl);
 538         default:
 539                 return uh_ubus_single_error(cl, ERROR_PARSE);
 540         }
 541 }
 542
 543 static int uh_ubus_data_send(struct client *cl, const char *data, int len)
 544 {
 545         struct dispatch_ubus *du = &cl->dispatch.ubus;
 546
 547         if (du->jsobj || !du->jstok)
 548                 goto error;
 549
 550         du->post_len += len;
 551         if (du->post_len > UH_UBUS_MAX_POST_SIZE)
 552                 goto error;
 553
 554         du->jsobj = json_tokener_parse_ex(du->jstok, data, len);
 555         return len;
 556
 557 error:
 558         uh_ubus_single_error(cl, ERROR_PARSE);
 559         return 0;
 560 }
 561
 562 static void uh_ubus_handle_request(struct client *cl, char *url, struct path_info *pi)
 563 {
 564         struct dispatch *d = &cl->dispatch;
 565
 566         blob_buf_init(&buf, 0);
 567
 568         if (cl->request.method != UH_HTTP_MSG_POST)
 569                 return ops->client_error(cl, 400, "Bad Request", "Invalid Request");
 570
 571         d->close_fds = uh_ubus_close_fds;
 572         d->free = uh_ubus_request_free;
 573         d->data_send = uh_ubus_data_send;
 574         d->data_done = uh_ubus_data_done;
 575         d->ubus.jstok = json_tokener_new();
 576 }
 577
 578 static bool
 579 uh_ubus_check_url(const char *url)
 580 {
 581         return ops->path_match(conf.ubus_prefix, url);
 582 }
 583
 584 static int
 585 uh_ubus_init(void)
 586 {
 587         static struct dispatch_handler ubus_dispatch = {
 588                 .check_url = uh_ubus_check_url,
 589                 .handle_request = uh_ubus_handle_request,
 590         };
 591
 592         ctx = ubus_connect(conf.ubus_socket);
 593         if (!ctx) {
 594                 fprintf(stderr, "Unable to connect to ubus socket\n");
 595                 exit(1);
 596         }
 597
 598         ops->dispatch_add(&ubus_dispatch);
 599
 600         uloop_done();
 601         return 0;
 602 }
 603
 604
 605 static int uh_ubus_plugin_init(const struct uhttpd_ops *o, struct config *c)
 606 {
 607         ops = o;
 608         _conf = c;
 609         return uh_ubus_init();
 610 }
 611
 612 static void uh_ubus_post_init(void)
 613 {
 614         ubus_add_uloop(ctx);
 615 }
 616
 617 const struct uhttpd_plugin uhttpd_plugin = {
 618         .init = uh_ubus_plugin_init,
 619         .post_init = uh_ubus_post_init,
 620 };