ubusd_proto.c

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