file.c

   1 /*
   2  * rpcd - UBUS RPC server
   3  *
   4  *   Copyright (C) 2013-2014 Jo-Philipp Wich <jow@openwrt.org>
   5  *   Copyright (C) 2016 Luka Perkov <luka@openwrt.org>
   6  *
   7  * Permission to use, copy, modify, and/or distribute this software for any
   8  * purpose with or without fee is hereby granted, provided that the above
   9  * copyright notice and this permission notice appear in all copies.
  10  *
  11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20 #define _GNU_SOURCE
  21
  22 #include <fcntl.h>
  23 #include <errno.h>
  24 #include <unistd.h>
  25 #include <stdint.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <limits.h>
  29 #include <dirent.h>
  30 #include <sys/stat.h>
  31 #include <sys/wait.h>
  32 #include <libubus.h>
  33 #include <libubox/blobmsg.h>
  34 #include <libubox/md5.h>
  35 #include <libubox/ustream.h>
  36 #include <libubox/utils.h>
  37
  38 #include <rpcd/plugin.h>
  39
  40 /* limit of sys & proc files */
  41 #define RPC_FILE_MIN_SIZE               (128)
  42
  43 /* limit of regular files and command output data */
  44 #define RPC_FILE_MAX_SIZE               (4096 * 64)
  45
  46 #define ustream_for_each_read_buffer(stream, ptr, len) \
  47         for (ptr = ustream_get_read_buf(stream, &len);     \
  48              ptr != NULL && len > 0;                       \
  49              ustream_consume(stream, len), ptr = ustream_get_read_buf(stream, &len))
  50
  51 #define ustream_declare(us, fd, name)                     \
  52         us.stream.string_data   = true;                       \
  53         us.stream.r.buffer_len  = 4096;                       \
  54         us.stream.r.max_buffers = RPC_FILE_MAX_SIZE / 4096;   \
  55         us.stream.notify_read   = rpc_file_##name##_read_cb;  \
  56         us.stream.notify_state  = rpc_file_##name##_state_cb; \
  57         ustream_fd_init(&us, fd);
  58
  59 static const struct rpc_daemon_ops *ops;
  60
  61 struct rpc_file_exec_context {
  62         struct ubus_context *context;
  63         struct ubus_request_data request;
  64         struct uloop_timeout timeout;
  65         struct uloop_process process;
  66         struct ustream_fd opipe;
  67         struct ustream_fd epipe;
  68         int stat;
  69 };
  70
  71
  72 static struct blob_buf buf;
  73 static char *canonpath;
  74
  75 enum {
  76         RPC_F_R_PATH,
  77         RPC_F_R_SESSION,
  78         __RPC_F_R_MAX,
  79 };
  80
  81 static const struct blobmsg_policy rpc_file_r_policy[__RPC_F_R_MAX] = {
  82         [RPC_F_R_PATH]    = { .name = "path", .type = BLOBMSG_TYPE_STRING },
  83         [RPC_F_R_SESSION] = { .name = "ubus_rpc_session",
  84                               .type = BLOBMSG_TYPE_STRING },
  85 };
  86
  87 enum {
  88         RPC_F_RB_PATH,
  89         RPC_F_RB_BASE64,
  90         RPC_F_RB_SESSION,
  91         __RPC_F_RB_MAX,
  92 };
  93
  94 static const struct blobmsg_policy rpc_file_rb_policy[__RPC_F_RB_MAX] = {
  95         [RPC_F_RB_PATH]    = { .name = "path",   .type = BLOBMSG_TYPE_STRING },
  96         [RPC_F_RB_BASE64]  = { .name = "base64", .type = BLOBMSG_TYPE_BOOL   },
  97         [RPC_F_RB_SESSION] = { .name = "ubus_rpc_session",
  98                                .type = BLOBMSG_TYPE_STRING },
  99 };
 100
 101 enum {
 102         RPC_F_RW_PATH,
 103         RPC_F_RW_DATA,
 104         RPC_F_RW_APPEND,
 105         RPC_F_RW_MODE,
 106         RPC_F_RW_BASE64,
 107         RPC_F_RW_SESSION,
 108         __RPC_F_RW_MAX,
 109 };
 110
 111 static const struct blobmsg_policy rpc_file_rw_policy[__RPC_F_RW_MAX] = {
 112         [RPC_F_RW_PATH]    = { .name = "path",   .type = BLOBMSG_TYPE_STRING },
 113         [RPC_F_RW_DATA]    = { .name = "data",   .type = BLOBMSG_TYPE_STRING },
 114         [RPC_F_RW_APPEND]  = { .name = "append", .type = BLOBMSG_TYPE_BOOL  },
 115         [RPC_F_RW_MODE]    = { .name = "mode",   .type = BLOBMSG_TYPE_INT32  },
 116         [RPC_F_RW_BASE64]  = { .name = "base64", .type = BLOBMSG_TYPE_BOOL   },
 117         [RPC_F_RW_SESSION] = { .name = "ubus_rpc_session",
 118                                .type = BLOBMSG_TYPE_STRING },
 119 };
 120
 121 enum {
 122         RPC_E_CMD,
 123         RPC_E_PARM,
 124         RPC_E_ENV,
 125         RPC_E_SESSION,
 126         __RPC_E_MAX,
 127 };
 128
 129 static const struct blobmsg_policy rpc_exec_policy[__RPC_E_MAX] = {
 130         [RPC_E_CMD]     = { .name = "command", .type = BLOBMSG_TYPE_STRING },
 131         [RPC_E_PARM]    = { .name = "params",  .type = BLOBMSG_TYPE_ARRAY  },
 132         [RPC_E_ENV]     = { .name = "env",     .type = BLOBMSG_TYPE_TABLE  },
 133         [RPC_E_SESSION] = { .name = "ubus_rpc_session",
 134                             .type = BLOBMSG_TYPE_STRING },
 135 };
 136
 137 static const char *d_types[] = {
 138         [DT_BLK]     = "block",
 139         [DT_CHR]     = "char",
 140         [DT_DIR]     = "directory",
 141         [DT_FIFO]    = "fifo",
 142         [DT_LNK]     = "symlink",
 143         [DT_REG]     = "file",
 144         [DT_SOCK]    = "socket",
 145         [DT_UNKNOWN] = "unknown",
 146 };
 147
 148
 149 static int
 150 rpc_errno_status(void)
 151 {
 152         switch (errno)
 153         {
 154         case EACCES:
 155                 return UBUS_STATUS_PERMISSION_DENIED;
 156
 157         case ENOTDIR:
 158                 return UBUS_STATUS_INVALID_ARGUMENT;
 159
 160         case ENOENT:
 161                 return UBUS_STATUS_NOT_FOUND;
 162
 163         case EINVAL:
 164                 return UBUS_STATUS_INVALID_ARGUMENT;
 165
 166         default:
 167                 return UBUS_STATUS_UNKNOWN_ERROR;
 168         }
 169 }
 170
 171 static bool
 172 rpc_file_read_access(const struct blob_attr *sid, const char *path)
 173 {
 174         if (!sid)
 175                 return true;
 176
 177         return ops->session_access(blobmsg_data(sid), "file", path, "read");
 178 }
 179
 180 static bool
 181 rpc_file_write_access(const struct blob_attr *sid, const char *path)
 182 {
 183         if (!sid)
 184                 return true;
 185
 186         return ops->session_access(blobmsg_data(sid), "file", path, "write");
 187 }
 188
 189 static bool
 190 rpc_file_exec_access(const struct blob_attr *sid, const char *path)
 191 {
 192         if (!sid)
 193                 return true;
 194
 195         return ops->session_access(blobmsg_data(sid), "file", path, "exec");
 196 }
 197
 198 static char *
 199 rpc_canonicalize_path(const char *path)
 200 {
 201         char *cp;
 202         const char *p;
 203
 204         if (path == NULL || *path == '\0')
 205                 return NULL;
 206
 207         if (canonpath != NULL)
 208                 free(canonpath);
 209
 210         canonpath = strdup(path);
 211
 212         if (canonpath == NULL)
 213                 return NULL;
 214
 215         /* normalize */
 216         for (cp = canonpath, p = path; *p != '\0'; ) {
 217                 if (*p != '/')
 218                         goto next;
 219
 220                 /* skip repeating / */
 221                 if (p[1] == '/') {
 222                         p++;
 223                         continue;
 224                 }
 225
 226                 /* /./ or /../ */
 227                 if (p[1] == '.') {
 228                         /* skip /./ */
 229                         if ((p[2] == '\0') || (p[2] == '/')) {
 230                                 p += 2;
 231                                 continue;
 232                         }
 233
 234                         /* collapse /x/../ */
 235                         if ((p[2] == '.') && ((p[3] == '\0') || (p[3] == '/'))) {
 236                                 while ((cp > canonpath) && (*--cp != '/'))
 237                                         ;
 238
 239                                 p += 3;
 240                                 continue;
 241                         }
 242                 }
 243
 244 next:
 245                 *cp++ = *p++;
 246         }
 247
 248         /* remove trailing slash if not root / */
 249         if ((cp > canonpath + 1) && (cp[-1] == '/'))
 250                 cp--;
 251         else if (cp == canonpath)
 252                 *cp++ = '/';
 253
 254         *cp = '\0';
 255
 256         return canonpath;
 257 }
 258
 259 static struct blob_attr **
 260 rpc_check_path(struct blob_attr *msg, char **path, struct stat *s)
 261 {
 262         static struct blob_attr *tb[__RPC_F_R_MAX];
 263
 264         blobmsg_parse(rpc_file_r_policy, __RPC_F_R_MAX, tb, blob_data(msg), blob_len(msg));
 265
 266         if (!tb[RPC_F_R_PATH])
 267         {
 268                 errno = EINVAL;
 269                 return NULL;
 270         }
 271
 272         *path = rpc_canonicalize_path(blobmsg_get_string(tb[RPC_F_R_PATH]));
 273
 274         if (*path == NULL)
 275         {
 276                 errno = ENOMEM;
 277                 return NULL;
 278         }
 279
 280         if (!rpc_file_read_access(tb[RPC_F_R_SESSION], *path))
 281         {
 282                 errno = EACCES;
 283                 return NULL;
 284         }
 285
 286         if (stat(*path, s))
 287                 return NULL;
 288
 289         return tb;
 290 }
 291
 292 static int
 293 rpc_file_read(struct ubus_context *ctx, struct ubus_object *obj,
 294               struct ubus_request_data *req, const char *method,
 295               struct blob_attr *msg)
 296 {
 297         static struct blob_attr *tb[__RPC_F_RB_MAX];
 298         bool base64 = false;
 299         int fd, rv;
 300         ssize_t len;
 301         char *path;
 302         struct stat s;
 303         char *wbuf;
 304
 305         blobmsg_parse(rpc_file_rb_policy, __RPC_F_RB_MAX, tb, blob_data(msg), blob_len(msg));
 306
 307         if (!tb[RPC_F_RB_PATH])
 308                 return rpc_errno_status();
 309
 310         path = rpc_canonicalize_path(blobmsg_get_string(tb[RPC_F_RB_PATH]));
 311
 312         if (path == NULL)
 313                 return UBUS_STATUS_UNKNOWN_ERROR;
 314
 315         if (!rpc_file_read_access(tb[RPC_F_RB_SESSION], path))
 316                 return UBUS_STATUS_PERMISSION_DENIED;
 317
 318         if (stat(path, &s))
 319                 return rpc_errno_status();
 320
 321         if (s.st_size >= RPC_FILE_MAX_SIZE)
 322                 return UBUS_STATUS_NOT_SUPPORTED;
 323
 324         if ((fd = open(path, O_RDONLY)) < 0)
 325                 return rpc_errno_status();
 326
 327         /* some sysfs files do not report a length */
 328         if (s.st_size == 0)
 329                 s.st_size = RPC_FILE_MIN_SIZE;
 330
 331         blob_buf_init(&buf, 0);
 332
 333         if (tb[RPC_F_RB_BASE64])
 334                 base64 = blobmsg_get_bool(tb[RPC_F_RB_BASE64]);
 335
 336         len = s.st_size + 1;
 337         if (base64)
 338                 len = B64_ENCODE_LEN(s.st_size);
 339         wbuf = blobmsg_alloc_string_buffer(&buf, "data", len);
 340
 341         if (!wbuf)
 342         {
 343                 rv = UBUS_STATUS_UNKNOWN_ERROR;
 344                 goto out;
 345         }
 346
 347         if ((len = read(fd, wbuf, s.st_size)) <= 0)
 348         {
 349                 rv = UBUS_STATUS_NO_DATA;
 350                 goto out;
 351         }
 352
 353         if (base64)
 354         {
 355                 uint8_t *data = calloc(len, sizeof(uint8_t));
 356                 if (!data)
 357                 {
 358                         rv = UBUS_STATUS_UNKNOWN_ERROR;
 359                         goto out;
 360                 }
 361                 memcpy(data, wbuf, len);
 362
 363                 len = b64_encode(data, len, wbuf, B64_ENCODE_LEN(len));
 364                 free(data);
 365                 if (len < 0)
 366                 {
 367                         rv = UBUS_STATUS_UNKNOWN_ERROR;
 368                         goto out;
 369                 }
 370         }
 371
 372         *(wbuf + len) = '\0';
 373         blobmsg_add_string_buffer(&buf);
 374
 375         ubus_send_reply(ctx, req, buf.head);
 376         rv = UBUS_STATUS_OK;
 377
 378 out:
 379         blob_buf_free(&buf);
 380         close(fd);
 381         return rv;
 382 }
 383
 384 static int
 385 rpc_file_write(struct ubus_context *ctx, struct ubus_object *obj,
 386                struct ubus_request_data *req, const char *method,
 387                struct blob_attr *msg)
 388 {
 389         struct blob_attr *tb[__RPC_F_RW_MAX];
 390         int append = O_TRUNC;
 391         mode_t prev_mode, mode = 0666;
 392         int fd, rv = 0;
 393         char *path = NULL;
 394         void *data = NULL;
 395         ssize_t data_len = 0;
 396
 397         blobmsg_parse(rpc_file_rw_policy, __RPC_F_RW_MAX, tb,
 398                       blob_data(msg), blob_len(msg));
 399
 400         if (!tb[RPC_F_RW_PATH] || !tb[RPC_F_RW_DATA])
 401                 return UBUS_STATUS_INVALID_ARGUMENT;
 402
 403         path = rpc_canonicalize_path(blobmsg_get_string(tb[RPC_F_RW_PATH]));
 404
 405         if (path == NULL)
 406                 return UBUS_STATUS_UNKNOWN_ERROR;
 407
 408         if (!rpc_file_write_access(tb[RPC_F_RW_SESSION], path))
 409                 return UBUS_STATUS_PERMISSION_DENIED;
 410
 411         data = blobmsg_data(tb[RPC_F_RW_DATA]);
 412         data_len = blobmsg_data_len(tb[RPC_F_RW_DATA]) - 1;
 413
 414         if (tb[RPC_F_RW_APPEND] && blobmsg_get_bool(tb[RPC_F_RW_APPEND]))
 415                 append = O_APPEND;
 416
 417         if (tb[RPC_F_RW_MODE])
 418                 mode = blobmsg_get_u32(tb[RPC_F_RW_MODE]);
 419
 420         prev_mode = umask(0);
 421         fd = open(path, O_CREAT | O_WRONLY | append, mode);
 422         umask(prev_mode);
 423         if (fd < 0)
 424                 return rpc_errno_status();
 425
 426         if (tb[RPC_F_RW_BASE64] && blobmsg_get_bool(tb[RPC_F_RW_BASE64]))
 427         {
 428                 data_len = b64_decode(data, data, data_len);
 429                 if (data_len < 0)
 430                 {
 431                         rv = UBUS_STATUS_UNKNOWN_ERROR;
 432                         goto out;
 433                 }
 434         }
 435
 436         if (write(fd, data, data_len) < 0)
 437                 rv = -1;
 438
 439 out:
 440         if (fsync(fd) < 0)
 441                 rv = -1;
 442
 443         close(fd);
 444         sync();
 445
 446         if (rv)
 447                 return rpc_errno_status();
 448
 449         return 0;
 450 }
 451
 452 static int
 453 rpc_file_md5(struct ubus_context *ctx, struct ubus_object *obj,
 454              struct ubus_request_data *req, const char *method,
 455              struct blob_attr *msg)
 456 {
 457         int rv, i;
 458         char *path;
 459         struct stat s;
 460         uint8_t md5[16];
 461         char *wbuf;
 462
 463         if (!rpc_check_path(msg, &path, &s))
 464                 return rpc_errno_status();
 465
 466         if (!S_ISREG(s.st_mode))
 467                 return UBUS_STATUS_NOT_SUPPORTED;
 468
 469         if ((rv = md5sum(path, md5)) <= 0)
 470                 return rpc_errno_status();
 471
 472         blob_buf_init(&buf, 0);
 473         wbuf = blobmsg_alloc_string_buffer(&buf, "md5", 33);
 474
 475         for (i = 0; i < 16; i++)
 476                 sprintf(wbuf + (i * 2), "%02x", (uint8_t) md5[i]);
 477
 478         blobmsg_add_string_buffer(&buf);
 479         ubus_send_reply(ctx, req, buf.head);
 480         blob_buf_free(&buf);
 481
 482         return UBUS_STATUS_OK;
 483 }
 484
 485 static void
 486 _rpc_file_add_stat(struct stat *s)
 487 {
 488         int type;
 489
 490         type = S_ISREG(s->st_mode) ? DT_REG :
 491                 S_ISDIR(s->st_mode) ? DT_DIR :
 492                  S_ISCHR(s->st_mode) ? DT_CHR :
 493                   S_ISBLK(s->st_mode) ? DT_BLK :
 494                    S_ISFIFO(s->st_mode) ? DT_FIFO :
 495                     S_ISLNK(s->st_mode) ? DT_LNK :
 496                      S_ISSOCK(s->st_mode) ? DT_SOCK :
 497                       DT_UNKNOWN;
 498
 499         blobmsg_add_string(&buf, "type", d_types[type]);
 500         blobmsg_add_u32(&buf, "size",  s->st_size);
 501         blobmsg_add_u32(&buf, "mode",  s->st_mode);
 502         blobmsg_add_u32(&buf, "atime", s->st_atime);
 503         blobmsg_add_u32(&buf, "mtime", s->st_mtime);
 504         blobmsg_add_u32(&buf, "ctime", s->st_ctime);
 505         blobmsg_add_u32(&buf, "inode", s->st_ino);
 506         blobmsg_add_u32(&buf, "uid",   s->st_uid);
 507         blobmsg_add_u32(&buf, "gid",   s->st_gid);
 508 }
 509
 510 static int
 511 rpc_file_list(struct ubus_context *ctx, struct ubus_object *obj,
 512               struct ubus_request_data *req, const char *method,
 513               struct blob_attr *msg)
 514 {
 515         DIR *fd;
 516         void *c, *d;
 517         struct stat s;
 518         struct dirent *e;
 519         char *path, *entrypath;
 520
 521         if (!rpc_check_path(msg, &path, &s))
 522                 return rpc_errno_status();
 523
 524         if ((fd = opendir(path)) == NULL)
 525                 return rpc_errno_status();
 526
 527         blob_buf_init(&buf, 0);
 528         c = blobmsg_open_array(&buf, "entries");
 529
 530         while ((e = readdir(fd)) != NULL)
 531         {
 532                 if (!strcmp(e->d_name, ".") || !strcmp(e->d_name, ".."))
 533                         continue;
 534
 535                 if (asprintf(&entrypath, "%s/%s", path, e->d_name) < 0)
 536                         continue;
 537
 538                 if (!stat(entrypath, &s))
 539                 {
 540                         d = blobmsg_open_table(&buf, NULL);
 541                         blobmsg_add_string(&buf, "name", e->d_name);
 542                         _rpc_file_add_stat(&s);
 543                         blobmsg_close_table(&buf, d);
 544                 }
 545
 546                 free(entrypath);
 547         }
 548
 549         closedir(fd);
 550
 551         blobmsg_close_array(&buf, c);
 552         ubus_send_reply(ctx, req, buf.head);
 553         blob_buf_free(&buf);
 554
 555         return 0;
 556 }
 557
 558 static int
 559 rpc_file_stat(struct ubus_context *ctx, struct ubus_object *obj,
 560               struct ubus_request_data *req, const char *method,
 561               struct blob_attr *msg)
 562 {
 563         char *path;
 564         struct stat s;
 565
 566         if (!rpc_check_path(msg, &path, &s))
 567                 return rpc_errno_status();
 568
 569         blob_buf_init(&buf, 0);
 570
 571         blobmsg_add_string(&buf, "path", path);
 572         _rpc_file_add_stat(&s);
 573
 574         ubus_send_reply(ctx, req, buf.head);
 575         blob_buf_free(&buf);
 576
 577         return 0;
 578 }
 579
 580 static const char *
 581 rpc_file_exec_lookup(const char *cmd)
 582 {
 583         struct stat s;
 584         int plen = 0, clen = strlen(cmd) + 1;
 585         char *search, *p;
 586         static char path[PATH_MAX];
 587
 588         if (!stat(cmd, &s) && S_ISREG(s.st_mode))
 589                 return cmd;
 590
 591         search = getenv("PATH");
 592
 593         if (!search)
 594                 search = "/bin:/usr/bin:/sbin:/usr/sbin";
 595
 596         p = search;
 597
 598         do
 599         {
 600                 if (*p != ':' && *p != '\0')
 601                         continue;
 602
 603                 plen = p - search;
 604
 605                 if ((plen + clen) >= sizeof(path))
 606                         continue;
 607
 608                 strncpy(path, search, plen);
 609                 sprintf(path + plen, "/%s", cmd);
 610
 611                 if (!stat(path, &s) && S_ISREG(s.st_mode))
 612                         return path;
 613
 614                 search = p + 1;
 615         }
 616         while (*p++);
 617
 618         return NULL;
 619 }
 620
 621
 622 static void
 623 rpc_ustream_to_blobmsg(struct ustream *s, const char *name)
 624 {
 625         int len;
 626         char *rbuf, *wbuf;
 627
 628         if ((len = ustream_pending_data(s, false)) > 0)
 629         {
 630                 wbuf = blobmsg_alloc_string_buffer(&buf, name, len + 1);
 631
 632                 if (!wbuf)
 633                         return;
 634
 635                 ustream_for_each_read_buffer(s, rbuf, len)
 636                 {
 637                         memcpy(wbuf, rbuf, len);
 638                         wbuf += len;
 639                 }
 640
 641                 *wbuf = 0;
 642                 blobmsg_add_string_buffer(&buf);
 643         }
 644 }
 645
 646 static void
 647 rpc_file_exec_reply(struct rpc_file_exec_context *c, int rv)
 648 {
 649         uloop_timeout_cancel(&c->timeout);
 650         uloop_process_delete(&c->process);
 651
 652         if (rv == UBUS_STATUS_OK)
 653         {
 654                 blob_buf_init(&buf, 0);
 655
 656                 blobmsg_add_u32(&buf, "code", WEXITSTATUS(c->stat));
 657
 658                 rpc_ustream_to_blobmsg(&c->opipe.stream, "stdout");
 659                 rpc_ustream_to_blobmsg(&c->epipe.stream, "stderr");
 660
 661                 ubus_send_reply(c->context, &c->request, buf.head);
 662                 blob_buf_free(&buf);
 663         }
 664
 665         ubus_complete_deferred_request(c->context, &c->request, rv);
 666
 667         ustream_free(&c->opipe.stream);
 668         ustream_free(&c->epipe.stream);
 669
 670         close(c->opipe.fd.fd);
 671         close(c->epipe.fd.fd);
 672
 673         free(c);
 674 }
 675
 676 static void
 677 rpc_file_exec_timeout_cb(struct uloop_timeout *t)
 678 {
 679         struct rpc_file_exec_context *c =
 680                 container_of(t, struct rpc_file_exec_context, timeout);
 681
 682         kill(c->process.pid, SIGKILL);
 683         rpc_file_exec_reply(c, UBUS_STATUS_TIMEOUT);
 684 }
 685
 686 static void
 687 rpc_file_exec_process_cb(struct uloop_process *p, int stat)
 688 {
 689         struct rpc_file_exec_context *c =
 690                 container_of(p, struct rpc_file_exec_context, process);
 691
 692         c->stat = stat;
 693
 694         ustream_poll(&c->opipe.stream);
 695         ustream_poll(&c->epipe.stream);
 696 }
 697
 698 static void
 699 rpc_file_exec_opipe_read_cb(struct ustream *s, int bytes)
 700 {
 701         struct rpc_file_exec_context *c =
 702                 container_of(s, struct rpc_file_exec_context, opipe.stream);
 703
 704         if (ustream_read_buf_full(s))
 705                 rpc_file_exec_reply(c, UBUS_STATUS_NOT_SUPPORTED);
 706 }
 707
 708 static void
 709 rpc_file_exec_epipe_read_cb(struct ustream *s, int bytes)
 710 {
 711         struct rpc_file_exec_context *c =
 712                 container_of(s, struct rpc_file_exec_context, epipe.stream);
 713
 714         if (ustream_read_buf_full(s))
 715                 rpc_file_exec_reply(c, UBUS_STATUS_NOT_SUPPORTED);
 716 }
 717
 718 static void
 719 rpc_file_exec_opipe_state_cb(struct ustream *s)
 720 {
 721         struct rpc_file_exec_context *c =
 722                 container_of(s, struct rpc_file_exec_context, opipe.stream);
 723
 724         if (c->opipe.stream.eof && c->epipe.stream.eof)
 725                 rpc_file_exec_reply(c, UBUS_STATUS_OK);
 726 }
 727
 728 static void
 729 rpc_file_exec_epipe_state_cb(struct ustream *s)
 730 {
 731         struct rpc_file_exec_context *c =
 732                 container_of(s, struct rpc_file_exec_context, epipe.stream);
 733
 734         if (c->opipe.stream.eof && c->epipe.stream.eof)
 735                 rpc_file_exec_reply(c, UBUS_STATUS_OK);
 736 }
 737
 738 static void
 739 rpc_fdclose(int fd)
 740 {
 741         if (fd > 2)
 742                 close(fd);
 743 }
 744
 745 static int
 746 rpc_file_exec_run(const char *cmd, const struct blob_attr *sid,
 747                   const struct blob_attr *arg, const struct blob_attr *env,
 748                   struct ubus_context *ctx, struct ubus_request_data *req)
 749 {
 750         pid_t pid;
 751
 752         int devnull;
 753         int opipe[2];
 754         int epipe[2];
 755
 756         int rem;
 757         struct blob_attr *cur;
 758
 759         uint8_t arglen;
 760         char *executable, **args, **tmp;
 761
 762         struct rpc_file_exec_context *c;
 763
 764         cmd = rpc_file_exec_lookup(cmd);
 765
 766         if (!cmd)
 767                 return UBUS_STATUS_NOT_FOUND;
 768
 769         executable = rpc_canonicalize_path(cmd);
 770
 771         if (executable == NULL)
 772                 return UBUS_STATUS_UNKNOWN_ERROR;
 773
 774         if (!rpc_file_exec_access(sid, executable))
 775                 return UBUS_STATUS_PERMISSION_DENIED;
 776
 777         c = malloc(sizeof(*c));
 778
 779         if (!c)
 780                 return UBUS_STATUS_UNKNOWN_ERROR;
 781
 782         if (pipe(opipe) || pipe(epipe))
 783                 return rpc_errno_status();
 784
 785         switch ((pid = fork()))
 786         {
 787         case -1:
 788                 return rpc_errno_status();
 789
 790         case 0:
 791                 uloop_done();
 792
 793                 devnull = open("/dev/null", O_RDWR);
 794
 795                 if (devnull == -1)
 796                         return UBUS_STATUS_UNKNOWN_ERROR;
 797
 798                 dup2(devnull, 0);
 799                 dup2(opipe[1], 1);
 800                 dup2(epipe[1], 2);
 801
 802                 rpc_fdclose(devnull);
 803                 rpc_fdclose(opipe[0]);
 804                 rpc_fdclose(opipe[1]);
 805                 rpc_fdclose(epipe[0]);
 806                 rpc_fdclose(epipe[1]);
 807
 808                 arglen = 2;
 809                 args = malloc(sizeof(char *) * arglen);
 810
 811                 if (!args)
 812                         return UBUS_STATUS_UNKNOWN_ERROR;
 813
 814                 args[0] = (char *)executable;
 815                 args[1] = NULL;
 816
 817                 if (arg)
 818                 {
 819                         blobmsg_for_each_attr(cur, arg, rem)
 820                         {
 821                                 if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING)
 822                                         continue;
 823
 824                                 if (arglen == 255)
 825                                 {
 826                                         free(args);
 827                                         return UBUS_STATUS_INVALID_ARGUMENT;
 828                                 }
 829
 830                                 arglen++;
 831                                 tmp = realloc(args, sizeof(char *) * arglen);
 832
 833                                 if (!tmp)
 834                                 {
 835                                         free(args);
 836                                         return UBUS_STATUS_UNKNOWN_ERROR;
 837                                 }
 838
 839                                 args = tmp;
 840                                 args[arglen-2] = blobmsg_data(cur);
 841                                 args[arglen-1] = NULL;
 842                         }
 843                 }
 844
 845                 if (env)
 846                 {
 847                         blobmsg_for_each_attr(cur, env, rem)
 848                         {
 849                                 if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING)
 850                                         continue;
 851
 852                                 setenv(blobmsg_name(cur), blobmsg_data(cur), 1);
 853                         }
 854                 }
 855
 856                 if (execv(executable, args))
 857                         return rpc_errno_status();
 858
 859         default:
 860                 memset(c, 0, sizeof(*c));
 861
 862                 ustream_declare(c->opipe, opipe[0], exec_opipe);
 863                 ustream_declare(c->epipe, epipe[0], exec_epipe);
 864
 865                 c->process.pid = pid;
 866                 c->process.cb = rpc_file_exec_process_cb;
 867                 uloop_process_add(&c->process);
 868
 869                 c->timeout.cb = rpc_file_exec_timeout_cb;
 870                 uloop_timeout_set(&c->timeout, *ops->exec_timeout);
 871
 872                 close(opipe[1]);
 873                 close(epipe[1]);
 874
 875                 c->context = ctx;
 876                 ubus_defer_request(ctx, req, &c->request);
 877         }
 878
 879         return UBUS_STATUS_OK;
 880 }
 881
 882 static int
 883 rpc_file_exec(struct ubus_context *ctx, struct ubus_object *obj,
 884               struct ubus_request_data *req, const char *method,
 885               struct blob_attr *msg)
 886 {
 887         struct blob_attr *tb[__RPC_E_MAX];
 888
 889         blobmsg_parse(rpc_exec_policy, __RPC_E_MAX, tb,
 890                       blob_data(msg), blob_len(msg));
 891
 892         if (!tb[RPC_E_CMD])
 893                 return UBUS_STATUS_INVALID_ARGUMENT;
 894
 895         return rpc_file_exec_run(blobmsg_data(tb[RPC_E_CMD]), tb[RPC_E_SESSION],
 896                                  tb[RPC_E_PARM], tb[RPC_E_ENV], ctx, req);
 897 }
 898
 899
 900 static int
 901 rpc_file_api_init(const struct rpc_daemon_ops *o, struct ubus_context *ctx)
 902 {
 903         static const struct ubus_method file_methods[] = {
 904                 UBUS_METHOD("read",    rpc_file_read,  rpc_file_rb_policy),
 905                 UBUS_METHOD("write",   rpc_file_write, rpc_file_rw_policy),
 906                 UBUS_METHOD("list",    rpc_file_list,  rpc_file_r_policy),
 907                 UBUS_METHOD("stat",    rpc_file_stat,  rpc_file_r_policy),
 908                 UBUS_METHOD("md5",     rpc_file_md5,   rpc_file_r_policy),
 909                 UBUS_METHOD("exec",    rpc_file_exec,  rpc_exec_policy),
 910         };
 911
 912         static struct ubus_object_type file_type =
 913                 UBUS_OBJECT_TYPE("luci-rpc-file", file_methods);
 914
 915         static struct ubus_object obj = {
 916                 .name = "file",
 917                 .type = &file_type,
 918                 .methods = file_methods,
 919                 .n_methods = ARRAY_SIZE(file_methods),
 920         };
 921
 922         ops = o;
 923
 924         return ubus_add_object(ctx, &obj);
 925 }
 926
 927 struct rpc_plugin rpc_plugin = {
 928         .init = rpc_file_api_init
 929 };