ubusd_proto.c

   1 /*
   2  * Copyright (C) 2011-2014 Felix Fietkau <nbd@openwrt.org>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU Lesser General Public License version 2.1
   6  * as published by the Free Software Foundation
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include <arpa/inet.h>
  15 #include <unistd.h>
  16
  17 #include "ubusd.h"
  18
  19 struct blob_buf b;
  20 static struct ubus_msg_buf *retmsg;
  21 static int *retmsg_data;
  22 static struct avl_tree clients;
  23
  24 static struct blob_attr *attrbuf[UBUS_ATTR_MAX];
  25
  26 typedef int (*ubus_cmd_cb)(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr);
  27
  28 static const struct blob_attr_info ubus_policy[UBUS_ATTR_MAX] = {
  29         [UBUS_ATTR_SIGNATURE] = { .type = BLOB_ATTR_NESTED },
  30         [UBUS_ATTR_OBJTYPE] = { .type = BLOB_ATTR_INT32 },
  31         [UBUS_ATTR_OBJPATH] = { .type = BLOB_ATTR_STRING },
  32         [UBUS_ATTR_OBJID] = { .type = BLOB_ATTR_INT32 },
  33         [UBUS_ATTR_STATUS] = { .type = BLOB_ATTR_INT32 },
  34         [UBUS_ATTR_METHOD] = { .type = BLOB_ATTR_STRING },
  35         [UBUS_ATTR_USER] = { .type = BLOB_ATTR_STRING },
  36         [UBUS_ATTR_GROUP] = { .type = BLOB_ATTR_STRING },
  37 };
  38
  39 struct blob_attr **ubus_parse_msg(struct blob_attr *msg)
  40 {
  41         blob_parse(msg, attrbuf, ubus_policy, UBUS_ATTR_MAX);
  42         return attrbuf;
  43 }
  44
  45 static void ubus_msg_close_fd(struct ubus_msg_buf *ub)
  46 {
  47         if (ub->fd < 0)
  48                 return;
  49
  50         close(ub->fd);
  51         ub->fd = -1;
  52 }
  53
  54 static void ubus_msg_init(struct ubus_msg_buf *ub, uint8_t type, uint16_t seq, uint32_t peer)
  55 {
  56         ub->hdr.version = 0;
  57         ub->hdr.type = type;
  58         ub->hdr.seq = seq;
  59         ub->hdr.peer = peer;
  60 }
  61
  62 static struct ubus_msg_buf *ubus_msg_from_blob(bool shared)
  63 {
  64         return ubus_msg_new(b.head, blob_raw_len(b.head), shared);
  65 }
  66
  67 static struct ubus_msg_buf *ubus_reply_from_blob(struct ubus_msg_buf *ub, bool shared)
  68 {
  69         struct ubus_msg_buf *new;
  70
  71         new = ubus_msg_from_blob(shared);
  72         if (!new)
  73                 return NULL;
  74
  75         ubus_msg_init(new, UBUS_MSG_DATA, ub->hdr.seq, ub->hdr.peer);
  76         return new;
  77 }
  78
  79 void
  80 ubus_proto_send_msg_from_blob(struct ubus_client *cl, struct ubus_msg_buf *ub,
  81                         uint8_t type)
  82 {
  83         /* keep the fd to be passed if it is UBUS_MSG_INVOKE */
  84         int fd = ub->fd;
  85         ub = ubus_reply_from_blob(ub, true);
  86         if (!ub)
  87                 return;
  88
  89         ub->hdr.type = type;
  90         ub->fd = fd;
  91
  92         ubus_msg_send(cl, ub, true);
  93 }
  94
  95 static bool ubusd_send_hello(struct ubus_client *cl)
  96 {
  97         struct ubus_msg_buf *ub;
  98
  99         blob_buf_init(&b, 0);
 100         ub = ubus_msg_from_blob(true);
 101         if (!ub)
 102                 return false;
 103
 104         ubus_msg_init(ub, UBUS_MSG_HELLO, 0, cl->id.id);
 105         ubus_msg_send(cl, ub, true);
 106         return true;
 107 }
 108
 109 static int ubusd_send_pong(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 110 {
 111         ub->hdr.type = UBUS_MSG_DATA;
 112         ubus_msg_send(cl, ub, false);
 113         return 0;
 114 }
 115
 116 static int ubusd_handle_remove_object(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 117 {
 118         struct ubus_object *obj;
 119
 120         if (!attr[UBUS_ATTR_OBJID])
 121                 return UBUS_STATUS_INVALID_ARGUMENT;
 122
 123         obj = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_OBJID]));
 124         if (!obj)
 125                 return UBUS_STATUS_NOT_FOUND;
 126
 127         if (obj->client != cl)
 128                 return UBUS_STATUS_PERMISSION_DENIED;
 129
 130         blob_buf_init(&b, 0);
 131         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
 132
 133         /* check if we're removing the object type as well */
 134         if (obj->type && obj->type->refcount == 1)
 135                 blob_put_int32(&b, UBUS_ATTR_OBJTYPE, obj->type->id.id);
 136
 137         ubus_proto_send_msg_from_blob(cl, ub, UBUS_MSG_DATA);
 138         ubusd_free_object(obj);
 139
 140         return 0;
 141 }
 142
 143 static int ubusd_handle_add_object(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 144 {
 145         struct ubus_object *obj;
 146
 147         obj = ubusd_create_object(cl, attr);
 148         if (!obj)
 149                 return UBUS_STATUS_INVALID_ARGUMENT;
 150
 151         blob_buf_init(&b, 0);
 152         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
 153         if (attr[UBUS_ATTR_SIGNATURE] && obj->type)
 154                 blob_put_int32(&b, UBUS_ATTR_OBJTYPE, obj->type->id.id);
 155
 156         ubus_proto_send_msg_from_blob(cl, ub, UBUS_MSG_DATA);
 157         return 0;
 158 }
 159
 160 static void ubusd_send_obj(struct ubus_client *cl, struct ubus_msg_buf *ub, struct ubus_object *obj)
 161 {
 162         struct ubus_method *m;
 163         int all_cnt = 0, cnt = 0;
 164         void *s;
 165
 166         if (!obj->type)
 167                 return;
 168
 169         blob_buf_init(&b, 0);
 170
 171         blob_put_string(&b, UBUS_ATTR_OBJPATH, obj->path.key);
 172         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
 173         blob_put_int32(&b, UBUS_ATTR_OBJTYPE, obj->type->id.id);
 174
 175         s = blob_nest_start(&b, UBUS_ATTR_SIGNATURE);
 176         list_for_each_entry(m, &obj->type->methods, list) {
 177                 all_cnt++;
 178                 if (!ubusd_acl_check(cl, obj->path.key, blobmsg_name(m->data), UBUS_ACL_ACCESS)) {
 179                         blobmsg_add_blob(&b, m->data);
 180                         cnt++;
 181                 }
 182         }
 183         blob_nest_end(&b, s);
 184
 185         if (cnt || !all_cnt)
 186                 ubus_proto_send_msg_from_blob(cl, ub, UBUS_MSG_DATA);
 187 }
 188
 189 static int ubusd_handle_lookup(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 190 {
 191         struct ubus_object *obj;
 192         char *objpath;
 193         bool found = false;
 194         int len;
 195
 196         if (!attr[UBUS_ATTR_OBJPATH]) {
 197                 avl_for_each_element(&path, obj, path)
 198                         ubusd_send_obj(cl, ub, obj);
 199                 return 0;
 200         }
 201
 202         objpath = blob_data(attr[UBUS_ATTR_OBJPATH]);
 203         len = strlen(objpath);
 204         if (objpath[len - 1] != '*') {
 205                 obj = avl_find_element(&path, objpath, obj, path);
 206                 if (!obj)
 207                         return UBUS_STATUS_NOT_FOUND;
 208
 209                 ubusd_send_obj(cl, ub, obj);
 210                 return 0;
 211         }
 212
 213         objpath[--len] = 0;
 214
 215         obj = avl_find_ge_element(&path, objpath, obj, path);
 216         if (!obj)
 217                 return UBUS_STATUS_NOT_FOUND;
 218
 219         while (!strncmp(objpath, obj->path.key, len)) {
 220                 found = true;
 221                 ubusd_send_obj(cl, ub, obj);
 222                 if (obj == avl_last_element(&path, obj, path))
 223                         break;
 224                 obj = avl_next_element(obj, path);
 225         }
 226
 227         if (!found)
 228                 return UBUS_STATUS_NOT_FOUND;
 229
 230         return 0;
 231 }
 232
 233 static void
 234 ubusd_forward_invoke(struct ubus_client *cl, struct ubus_object *obj,
 235                      const char *method, struct ubus_msg_buf *ub,
 236                      struct blob_attr *data)
 237 {
 238         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
 239         blob_put_string(&b, UBUS_ATTR_METHOD, method);
 240         if (cl->user)
 241                 blob_put_string(&b, UBUS_ATTR_USER, cl->user);
 242         if (cl->group)
 243                 blob_put_string(&b, UBUS_ATTR_GROUP, cl->group);
 244         if (data)
 245                 blob_put(&b, UBUS_ATTR_DATA, blob_data(data), blob_len(data));
 246
 247         ubus_proto_send_msg_from_blob(obj->client, ub, UBUS_MSG_INVOKE);
 248 }
 249
 250 static int ubusd_handle_invoke(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 251 {
 252         struct ubus_object *obj = NULL;
 253         struct ubus_id *id;
 254         const char *method;
 255
 256         if (!attr[UBUS_ATTR_METHOD] || !attr[UBUS_ATTR_OBJID])
 257                 return UBUS_STATUS_INVALID_ARGUMENT;
 258
 259         id = ubus_find_id(&objects, blob_get_u32(attr[UBUS_ATTR_OBJID]));
 260         if (!id)
 261                 return UBUS_STATUS_NOT_FOUND;
 262
 263         obj = container_of(id, struct ubus_object, id);
 264
 265         method = blob_data(attr[UBUS_ATTR_METHOD]);
 266
 267         if (ubusd_acl_check(cl, obj->path.key, method, UBUS_ACL_ACCESS))
 268                 return UBUS_STATUS_PERMISSION_DENIED;
 269
 270         if (!obj->client)
 271                 return obj->recv_msg(cl, ub, method, attr[UBUS_ATTR_DATA]);
 272
 273         ub->hdr.peer = cl->id.id;
 274         blob_buf_init(&b, 0);
 275
 276         ubusd_forward_invoke(cl, obj, method, ub, attr[UBUS_ATTR_DATA]);
 277         ubus_msg_free(ub);
 278
 279         return -1;
 280 }
 281
 282 static int ubusd_handle_notify(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 283 {
 284         struct ubus_object *obj = NULL;
 285         struct ubus_subscription *s;
 286         struct ubus_id *id;
 287         const char *method;
 288         bool no_reply = false;
 289         void *c;
 290
 291         if (!attr[UBUS_ATTR_METHOD] || !attr[UBUS_ATTR_OBJID])
 292                 return UBUS_STATUS_INVALID_ARGUMENT;
 293
 294         if (attr[UBUS_ATTR_NO_REPLY])
 295                 no_reply = blob_get_int8(attr[UBUS_ATTR_NO_REPLY]);
 296
 297         id = ubus_find_id(&objects, blob_get_u32(attr[UBUS_ATTR_OBJID]));
 298         if (!id)
 299                 return UBUS_STATUS_NOT_FOUND;
 300
 301         obj = container_of(id, struct ubus_object, id);
 302         if (obj->client != cl)
 303                 return UBUS_STATUS_PERMISSION_DENIED;
 304
 305         if (!no_reply) {
 306                 blob_buf_init(&b, 0);
 307                 blob_put_int32(&b, UBUS_ATTR_OBJID, id->id);
 308                 c = blob_nest_start(&b, UBUS_ATTR_SUBSCRIBERS);
 309                 list_for_each_entry(s, &obj->subscribers, list) {
 310                         blob_put_int32(&b, 0, s->subscriber->id.id);
 311                 }
 312                 blob_nest_end(&b, c);
 313                 blob_put_int32(&b, UBUS_ATTR_STATUS, 0);
 314                 ubus_proto_send_msg_from_blob(cl, ub, UBUS_MSG_STATUS);
 315         }
 316
 317         ub->hdr.peer = cl->id.id;
 318         method = blob_data(attr[UBUS_ATTR_METHOD]);
 319         list_for_each_entry(s, &obj->subscribers, list) {
 320                 blob_buf_init(&b, 0);
 321                 if (no_reply)
 322                         blob_put_int8(&b, UBUS_ATTR_NO_REPLY, 1);
 323                 ubusd_forward_invoke(cl, s->subscriber, method, ub, attr[UBUS_ATTR_DATA]);
 324         }
 325         ubus_msg_free(ub);
 326
 327         return -1;
 328 }
 329
 330 static struct ubus_client *ubusd_get_client_by_id(uint32_t id)
 331 {
 332         struct ubus_id *clid;
 333
 334         clid = ubus_find_id(&clients, id);
 335         if (!clid)
 336                 return NULL;
 337
 338         return container_of(clid, struct ubus_client, id);
 339 }
 340
 341 static int ubusd_handle_response(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 342 {
 343         struct ubus_object *obj;
 344
 345         if (!attr[UBUS_ATTR_OBJID] ||
 346             (ub->hdr.type == UBUS_MSG_STATUS && !attr[UBUS_ATTR_STATUS]) ||
 347             (ub->hdr.type == UBUS_MSG_DATA && !attr[UBUS_ATTR_DATA]))
 348                 goto error;
 349
 350         obj = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_OBJID]));
 351         if (!obj)
 352                 goto error;
 353
 354         if (cl != obj->client)
 355                 goto error;
 356
 357         cl = ubusd_get_client_by_id(ub->hdr.peer);
 358         if (!cl)
 359                 goto error;
 360
 361         ub->hdr.peer = blob_get_u32(attr[UBUS_ATTR_OBJID]);
 362         ubus_msg_send(cl, ub, true);
 363         return -1;
 364
 365 error:
 366         ubus_msg_free(ub);
 367         return -1;
 368 }
 369
 370 static int ubusd_handle_add_watch(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 371 {
 372         struct ubus_object *obj, *target;
 373
 374         if (!attr[UBUS_ATTR_OBJID] || !attr[UBUS_ATTR_TARGET])
 375                 return UBUS_STATUS_INVALID_ARGUMENT;
 376
 377         obj = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_OBJID]));
 378         if (!obj)
 379                 return UBUS_STATUS_NOT_FOUND;
 380
 381         if (cl != obj->client)
 382                 return UBUS_STATUS_INVALID_ARGUMENT;
 383
 384         target = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_TARGET]));
 385         if (!target || !target->client)
 386                 return UBUS_STATUS_NOT_FOUND;
 387
 388         if (cl == target->client)
 389                 return UBUS_STATUS_INVALID_ARGUMENT;
 390
 391         if (!target->path.key) {
 392                 if (strcmp(target->client->user, cl->user) && strcmp(target->client->group, cl->group))
 393                         return UBUS_STATUS_NOT_FOUND;
 394         } else if (ubusd_acl_check(cl, target->path.key, NULL, UBUS_ACL_SUBSCRIBE)) {
 395                 return UBUS_STATUS_NOT_FOUND;
 396         }
 397
 398         ubus_subscribe(obj, target);
 399         return 0;
 400 }
 401
 402 static int ubusd_handle_remove_watch(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 403 {
 404         struct ubus_object *obj;
 405         struct ubus_subscription *s;
 406         uint32_t id;
 407
 408         if (!attr[UBUS_ATTR_OBJID] || !attr[UBUS_ATTR_TARGET])
 409                 return UBUS_STATUS_INVALID_ARGUMENT;
 410
 411         obj = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_OBJID]));
 412         if (!obj)
 413                 return UBUS_STATUS_NOT_FOUND;
 414
 415         if (cl != obj->client)
 416                 return UBUS_STATUS_INVALID_ARGUMENT;
 417
 418         id = blob_get_u32(attr[UBUS_ATTR_TARGET]);
 419         list_for_each_entry(s, &obj->target_list, target_list) {
 420                 if (s->target->id.id != id)
 421                         continue;
 422
 423                 ubus_unsubscribe(s);
 424                 return 0;
 425         }
 426
 427         return UBUS_STATUS_NOT_FOUND;
 428 }
 429
 430 static const ubus_cmd_cb handlers[__UBUS_MSG_LAST] = {
 431         [UBUS_MSG_PING] = ubusd_send_pong,
 432         [UBUS_MSG_ADD_OBJECT] = ubusd_handle_add_object,
 433         [UBUS_MSG_REMOVE_OBJECT] = ubusd_handle_remove_object,
 434         [UBUS_MSG_LOOKUP] = ubusd_handle_lookup,
 435         [UBUS_MSG_INVOKE] = ubusd_handle_invoke,
 436         [UBUS_MSG_STATUS] = ubusd_handle_response,
 437         [UBUS_MSG_DATA] = ubusd_handle_response,
 438         [UBUS_MSG_SUBSCRIBE] = ubusd_handle_add_watch,
 439         [UBUS_MSG_UNSUBSCRIBE] = ubusd_handle_remove_watch,
 440         [UBUS_MSG_NOTIFY] = ubusd_handle_notify,
 441 };
 442
 443 void ubusd_proto_receive_message(struct ubus_client *cl, struct ubus_msg_buf *ub)
 444 {
 445         ubus_cmd_cb cb = NULL;
 446         int ret;
 447
 448         retmsg->hdr.seq = ub->hdr.seq;
 449         retmsg->hdr.peer = ub->hdr.peer;
 450
 451         if (ub->hdr.type < __UBUS_MSG_LAST)
 452                 cb = handlers[ub->hdr.type];
 453
 454         if (ub->hdr.type != UBUS_MSG_STATUS && ub->hdr.type != UBUS_MSG_INVOKE)
 455                 ubus_msg_close_fd(ub);
 456
 457         if (cb)
 458                 ret = cb(cl, ub, ubus_parse_msg(ub->data));
 459         else
 460                 ret = UBUS_STATUS_INVALID_COMMAND;
 461
 462         if (ret == -1)
 463                 return;
 464
 465         ubus_msg_free(ub);
 466
 467         *retmsg_data = htonl(ret);
 468         ubus_msg_send(cl, retmsg, false);
 469 }
 470
 471 struct ubus_client *ubusd_proto_new_client(int fd, uloop_fd_handler cb)
 472 {
 473         struct ubus_client *cl;
 474
 475         cl = calloc(1, sizeof(*cl));
 476         if (!cl)
 477                 return NULL;
 478
 479         if (ubusd_acl_init_client(cl, fd))
 480                 goto free;
 481
 482         INIT_LIST_HEAD(&cl->objects);
 483         cl->sock.fd = fd;
 484         cl->sock.cb = cb;
 485         cl->pending_msg_fd = -1;
 486
 487         if (!ubus_alloc_id(&clients, &cl->id, 0))
 488                 goto free;
 489
 490         if (!ubusd_send_hello(cl))
 491                 goto delete;
 492
 493         return cl;
 494
 495 delete:
 496         ubus_free_id(&clients, &cl->id);
 497 free:
 498         free(cl);
 499         return NULL;
 500 }
 501
 502 void ubusd_proto_free_client(struct ubus_client *cl)
 503 {
 504         struct ubus_object *obj;
 505
 506         while (!list_empty(&cl->objects)) {
 507                 obj = list_first_entry(&cl->objects, struct ubus_object, list);
 508                 ubusd_free_object(obj);
 509         }
 510
 511         ubusd_acl_free_client(cl);
 512         ubus_free_id(&clients, &cl->id);
 513 }
 514
 515 void ubus_notify_subscription(struct ubus_object *obj)
 516 {
 517         bool active = !list_empty(&obj->subscribers);
 518         struct ubus_msg_buf *ub;
 519
 520         blob_buf_init(&b, 0);
 521         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
 522         blob_put_int8(&b, UBUS_ATTR_ACTIVE, active);
 523
 524         ub = ubus_msg_from_blob(false);
 525         if (!ub)
 526                 return;
 527
 528         ubus_msg_init(ub, UBUS_MSG_NOTIFY, ++obj->invoke_seq, 0);
 529         ubus_msg_send(obj->client, ub, true);
 530 }
 531
 532 void ubus_notify_unsubscribe(struct ubus_subscription *s)
 533 {
 534         struct ubus_msg_buf *ub;
 535
 536         blob_buf_init(&b, 0);
 537         blob_put_int32(&b, UBUS_ATTR_OBJID, s->subscriber->id.id);
 538         blob_put_int32(&b, UBUS_ATTR_TARGET, s->target->id.id);
 539
 540         ub = ubus_msg_from_blob(false);
 541         if (ub != NULL) {
 542                 ubus_msg_init(ub, UBUS_MSG_UNSUBSCRIBE, ++s->subscriber->invoke_seq, 0);
 543                 ubus_msg_send(s->subscriber->client, ub, true);
 544         }
 545
 546         ubus_unsubscribe(s);
 547 }
 548
 549 static void __constructor ubusd_proto_init(void)
 550 {
 551         ubus_init_id_tree(&clients);
 552
 553         blob_buf_init(&b, 0);
 554         blob_put_int32(&b, UBUS_ATTR_STATUS, 0);
 555
 556         retmsg = ubus_msg_from_blob(false);
 557         if (!retmsg)
 558                 exit(1);
 559
 560         retmsg->hdr.type = UBUS_MSG_STATUS;
 561         retmsg_data = blob_data(blob_data(retmsg->data));
 562 }