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         if (obj->path.key)
 162                 blob_put_string(&b, UBUS_ATTR_OBJPATH, obj->path.key);
 163         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
 164         blob_put_int32(&b, UBUS_ATTR_OBJTYPE, obj->type->id.id);
 165
 166         s = blob_nest_start(&b, UBUS_ATTR_SIGNATURE);
 167         list_for_each_entry(m, &obj->type->methods, list)
 168                 blobmsg_add_blob(&b, m->data);
 169         blob_nest_end(&b, s);
 170
 171         ubus_send_msg_from_blob(cl, ub, UBUS_MSG_DATA);
 172 }
 173
 174 static int ubusd_handle_lookup(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 175 {
 176         struct ubus_object *obj;
 177         char *objpath;
 178         bool found = false;
 179         int len;
 180
 181         if (!attr[UBUS_ATTR_OBJPATH]) {
 182                 avl_for_each_element(&path, obj, path)
 183                         ubusd_send_obj(cl, ub, obj);
 184                 return 0;
 185         }
 186
 187         objpath = blob_data(attr[UBUS_ATTR_OBJPATH]);
 188         len = strlen(objpath);
 189         if (objpath[len - 1] != '*') {
 190                 obj = avl_find_element(&path, objpath, obj, path);
 191                 if (!obj)
 192                         return UBUS_STATUS_NOT_FOUND;
 193
 194                 ubusd_send_obj(cl, ub, obj);
 195                 return 0;
 196         }
 197
 198         objpath[--len] = 0;
 199
 200         obj = avl_find_ge_element(&path, objpath, obj, path);
 201         if (!obj)
 202                 return UBUS_STATUS_NOT_FOUND;
 203
 204         while (!strncmp(objpath, obj->path.key, len)) {
 205                 found = true;
 206                 ubusd_send_obj(cl, ub, obj);
 207                 if (obj == avl_last_element(&path, obj, path))
 208                         break;
 209                 obj = avl_next_element(obj, path);
 210         }
 211
 212         if (!found)
 213                 return UBUS_STATUS_NOT_FOUND;
 214
 215         return 0;
 216 }
 217
 218 static void
 219 ubusd_forward_invoke(struct ubus_object *obj, const char *method,
 220                      struct ubus_msg_buf *ub, struct blob_attr *data)
 221 {
 222         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
 223         blob_put_string(&b, UBUS_ATTR_METHOD, method);
 224         if (data)
 225                 blob_put(&b, UBUS_ATTR_DATA, blob_data(data), blob_len(data));
 226
 227         ubus_send_msg_from_blob(obj->client, ub, UBUS_MSG_INVOKE);
 228 }
 229
 230 static int ubusd_handle_invoke(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 231 {
 232         struct ubus_object *obj = NULL;
 233         struct ubus_id *id;
 234         const char *method;
 235
 236         if (!attr[UBUS_ATTR_METHOD] || !attr[UBUS_ATTR_OBJID])
 237                 return UBUS_STATUS_INVALID_ARGUMENT;
 238
 239         id = ubus_find_id(&objects, blob_get_u32(attr[UBUS_ATTR_OBJID]));
 240         if (!id)
 241                 return UBUS_STATUS_NOT_FOUND;
 242
 243         obj = container_of(id, struct ubus_object, id);
 244
 245         method = blob_data(attr[UBUS_ATTR_METHOD]);
 246
 247         if (!obj->client)
 248                 return obj->recv_msg(cl, method, attr[UBUS_ATTR_DATA]);
 249
 250         ub->hdr.peer = cl->id.id;
 251         blob_buf_init(&b, 0);
 252         ubusd_forward_invoke(obj, method, ub, attr[UBUS_ATTR_DATA]);
 253         ubus_msg_free(ub);
 254
 255         return -1;
 256 }
 257
 258 static int ubusd_handle_notify(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 259 {
 260         struct ubus_object *obj = NULL;
 261         struct ubus_subscription *s;
 262         struct ubus_id *id;
 263         const char *method;
 264         bool no_reply = false;
 265         void *c;
 266
 267         if (!attr[UBUS_ATTR_METHOD] || !attr[UBUS_ATTR_OBJID])
 268                 return UBUS_STATUS_INVALID_ARGUMENT;
 269
 270         if (attr[UBUS_ATTR_NO_REPLY])
 271                 no_reply = blob_get_int8(attr[UBUS_ATTR_NO_REPLY]);
 272
 273         id = ubus_find_id(&objects, blob_get_u32(attr[UBUS_ATTR_OBJID]));
 274         if (!id)
 275                 return UBUS_STATUS_NOT_FOUND;
 276
 277         obj = container_of(id, struct ubus_object, id);
 278         if (obj->client != cl)
 279                 return UBUS_STATUS_PERMISSION_DENIED;
 280
 281         if (!no_reply) {
 282                 blob_buf_init(&b, 0);
 283                 blob_put_int32(&b, UBUS_ATTR_OBJID, id->id);
 284                 c = blob_nest_start(&b, UBUS_ATTR_SUBSCRIBERS);
 285                 list_for_each_entry(s, &obj->subscribers, list) {
 286                         blob_put_int32(&b, 0, s->subscriber->id.id);
 287                 }
 288                 blob_nest_end(&b, c);
 289                 blob_put_int32(&b, UBUS_ATTR_STATUS, 0);
 290                 ubus_send_msg_from_blob(cl, ub, UBUS_MSG_STATUS);
 291         }
 292
 293         ub->hdr.peer = cl->id.id;
 294         method = blob_data(attr[UBUS_ATTR_METHOD]);
 295         list_for_each_entry(s, &obj->subscribers, list) {
 296                 blob_buf_init(&b, 0);
 297                 if (no_reply)
 298                         blob_put_int8(&b, UBUS_ATTR_NO_REPLY, 1);
 299                 ubusd_forward_invoke(s->subscriber, method, ub, attr[UBUS_ATTR_DATA]);
 300         }
 301         ubus_msg_free(ub);
 302
 303         return -1;
 304 }
 305
 306 static struct ubus_client *ubusd_get_client_by_id(uint32_t id)
 307 {
 308         struct ubus_id *clid;
 309
 310         clid = ubus_find_id(&clients, id);
 311         if (!clid)
 312                 return NULL;
 313
 314         return container_of(clid, struct ubus_client, id);
 315 }
 316
 317 static int ubusd_handle_response(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 318 {
 319         struct ubus_object *obj;
 320
 321         if (!attr[UBUS_ATTR_OBJID] ||
 322             (ub->hdr.type == UBUS_MSG_STATUS && !attr[UBUS_ATTR_STATUS]) ||
 323             (ub->hdr.type == UBUS_MSG_DATA && !attr[UBUS_ATTR_DATA]))
 324                 goto error;
 325
 326         obj = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_OBJID]));
 327         if (!obj)
 328                 goto error;
 329
 330         if (cl != obj->client)
 331                 goto error;
 332
 333         cl = ubusd_get_client_by_id(ub->hdr.peer);
 334         if (!cl)
 335                 goto error;
 336
 337         ub->hdr.peer = blob_get_u32(attr[UBUS_ATTR_OBJID]);
 338         ubus_msg_send(cl, ub, true);
 339         return -1;
 340
 341 error:
 342         ubus_msg_free(ub);
 343         return -1;
 344 }
 345
 346 static int ubusd_handle_add_watch(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 347 {
 348         struct ubus_object *obj, *target;
 349
 350         if (!attr[UBUS_ATTR_OBJID] || !attr[UBUS_ATTR_TARGET])
 351                 return UBUS_STATUS_INVALID_ARGUMENT;
 352
 353         obj = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_OBJID]));
 354         if (!obj)
 355                 return UBUS_STATUS_NOT_FOUND;
 356
 357         if (cl != obj->client)
 358                 return UBUS_STATUS_INVALID_ARGUMENT;
 359
 360         target = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_TARGET]));
 361         if (!target)
 362                 return UBUS_STATUS_NOT_FOUND;
 363
 364         if (cl == target->client)
 365                 return UBUS_STATUS_INVALID_ARGUMENT;
 366
 367         ubus_subscribe(obj, target);
 368         return 0;
 369 }
 370
 371 static int ubusd_handle_remove_watch(struct ubus_client *cl, struct ubus_msg_buf *ub, struct blob_attr **attr)
 372 {
 373         struct ubus_object *obj;
 374         struct ubus_subscription *s;
 375         uint32_t id;
 376
 377         if (!attr[UBUS_ATTR_OBJID] || !attr[UBUS_ATTR_TARGET])
 378                 return UBUS_STATUS_INVALID_ARGUMENT;
 379
 380         obj = ubusd_find_object(blob_get_u32(attr[UBUS_ATTR_OBJID]));
 381         if (!obj)
 382                 return UBUS_STATUS_NOT_FOUND;
 383
 384         if (cl != obj->client)
 385                 return UBUS_STATUS_INVALID_ARGUMENT;
 386
 387         id = blob_get_u32(attr[UBUS_ATTR_TARGET]);
 388         list_for_each_entry(s, &obj->target_list, target_list) {
 389                 if (s->target->id.id != id)
 390                         continue;
 391
 392                 ubus_unsubscribe(s);
 393                 return 0;
 394         }
 395
 396         return UBUS_STATUS_NOT_FOUND;
 397 }
 398
 399 static const ubus_cmd_cb handlers[__UBUS_MSG_LAST] = {
 400         [UBUS_MSG_PING] = ubusd_send_pong,
 401         [UBUS_MSG_ADD_OBJECT] = ubusd_handle_add_object,
 402         [UBUS_MSG_REMOVE_OBJECT] = ubusd_handle_remove_object,
 403         [UBUS_MSG_LOOKUP] = ubusd_handle_lookup,
 404         [UBUS_MSG_INVOKE] = ubusd_handle_invoke,
 405         [UBUS_MSG_STATUS] = ubusd_handle_response,
 406         [UBUS_MSG_DATA] = ubusd_handle_response,
 407         [UBUS_MSG_SUBSCRIBE] = ubusd_handle_add_watch,
 408         [UBUS_MSG_UNSUBSCRIBE] = ubusd_handle_remove_watch,
 409         [UBUS_MSG_NOTIFY] = ubusd_handle_notify,
 410 };
 411
 412 void ubusd_proto_receive_message(struct ubus_client *cl, struct ubus_msg_buf *ub)
 413 {
 414         ubus_cmd_cb cb = NULL;
 415         int ret;
 416
 417         retmsg->hdr.seq = ub->hdr.seq;
 418         retmsg->hdr.peer = ub->hdr.peer;
 419
 420         if (ub->hdr.type < __UBUS_MSG_LAST)
 421                 cb = handlers[ub->hdr.type];
 422
 423         if (ub->hdr.type != UBUS_MSG_STATUS)
 424                 ubus_msg_close_fd(ub);
 425
 426         if (cb)
 427                 ret = cb(cl, ub, ubus_parse_msg(ub->data));
 428         else
 429                 ret = UBUS_STATUS_INVALID_COMMAND;
 430
 431         if (ret == -1)
 432                 return;
 433
 434         ubus_msg_free(ub);
 435
 436         *retmsg_data = htonl(ret);
 437         ubus_msg_send(cl, retmsg, false);
 438 }
 439
 440 struct ubus_client *ubusd_proto_new_client(int fd, uloop_fd_handler cb)
 441 {
 442         struct ubus_client *cl;
 443
 444         cl = calloc(1, sizeof(*cl));
 445         if (!cl)
 446                 return NULL;
 447
 448         INIT_LIST_HEAD(&cl->objects);
 449         cl->sock.fd = fd;
 450         cl->sock.cb = cb;
 451         cl->pending_msg_fd = -1;
 452
 453         if (!ubus_alloc_id(&clients, &cl->id, 0))
 454                 goto free;
 455
 456         if (!ubusd_send_hello(cl))
 457                 goto delete;
 458
 459         return cl;
 460
 461 delete:
 462         ubus_free_id(&clients, &cl->id);
 463 free:
 464         free(cl);
 465         return NULL;
 466 }
 467
 468 void ubusd_proto_free_client(struct ubus_client *cl)
 469 {
 470         struct ubus_object *obj;
 471
 472         while (!list_empty(&cl->objects)) {
 473                 obj = list_first_entry(&cl->objects, struct ubus_object, list);
 474                 ubusd_free_object(obj);
 475         }
 476
 477         ubus_free_id(&clients, &cl->id);
 478 }
 479
 480 void ubus_notify_subscription(struct ubus_object *obj)
 481 {
 482         bool active = !list_empty(&obj->subscribers);
 483         struct ubus_msg_buf *ub;
 484
 485         blob_buf_init(&b, 0);
 486         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id);
 487         blob_put_int8(&b, UBUS_ATTR_ACTIVE, active);
 488
 489         ub = ubus_msg_from_blob(false);
 490         ubus_msg_init(ub, UBUS_MSG_NOTIFY, ++obj->invoke_seq, 0);
 491         ubus_msg_send(obj->client, ub, true);
 492 }
 493
 494 void ubus_notify_unsubscribe(struct ubus_subscription *s)
 495 {
 496         struct ubus_msg_buf *ub;
 497
 498         blob_buf_init(&b, 0);
 499         blob_put_int32(&b, UBUS_ATTR_OBJID, s->subscriber->id.id);
 500         blob_put_int32(&b, UBUS_ATTR_TARGET, s->target->id.id);
 501
 502         ub = ubus_msg_from_blob(false);
 503         ubus_msg_init(ub, UBUS_MSG_UNSUBSCRIBE, ++s->subscriber->invoke_seq, 0);
 504         ubus_msg_send(s->subscriber->client, ub, true);
 505
 506         ubus_unsubscribe(s);
 507 }
 508
 509 static void __init ubusd_proto_init(void)
 510 {
 511         ubus_init_id_tree(&clients);
 512
 513         blob_buf_init(&b, 0);
 514         blob_put_int32(&b, UBUS_ATTR_STATUS, 0);
 515
 516         retmsg = ubus_msg_from_blob(false);
 517         if (!retmsg)
 518                 exit(1);
 519
 520         retmsg->hdr.type = UBUS_MSG_STATUS;
 521         retmsg_data = blob_data(blob_data(retmsg->data));
 522 }