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