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