1 /* $NetBSD: sftp-server.c,v 1.12 2015/07/03 01:00:00 christos Exp $ */ 2 /* $OpenBSD: sftp-server.c,v 1.106 2015/04/24 01:36:01 deraadt Exp $ */ 3 /* 4 * Copyright (c) 2000-2004 Markus Friedl. All rights reserved. 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19 #include "includes.h" 20 __RCSID("$NetBSD: sftp-server.c,v 1.12 2015/07/03 01:00:00 christos Exp $"); 21 #include <sys/param.h> /* MIN */ 22 #include <sys/types.h> 23 #include <sys/stat.h> 24 #include <sys/time.h> 25 #include <sys/mount.h> 26 #include <sys/statvfs.h> 27 28 #include <dirent.h> 29 #include <errno.h> 30 #include <fcntl.h> 31 #include <stdlib.h> 32 #include <stdio.h> 33 #include <string.h> 34 #include <pwd.h> 35 #include <time.h> 36 #include <unistd.h> 37 #include <stdarg.h> 38 39 #include "xmalloc.h" 40 #include "sshbuf.h" 41 #include "ssherr.h" 42 #include "log.h" 43 #include "misc.h" 44 #include "match.h" 45 #include "uidswap.h" 46 47 #include "sftp.h" 48 #include "sftp-common.h" 49 50 /* Our verbosity */ 51 static LogLevel log_level = SYSLOG_LEVEL_ERROR; 52 53 /* Our client */ 54 static struct passwd *pw = NULL; 55 static char *client_addr = NULL; 56 57 /* input and output queue */ 58 struct sshbuf *iqueue; 59 struct sshbuf *oqueue; 60 61 /* Version of client */ 62 static u_int version; 63 64 /* SSH2_FXP_INIT received */ 65 static int init_done; 66 67 /* Disable writes */ 68 static int readonly; 69 70 /* Requests that are allowed/denied */ 71 static char *request_whitelist, *request_blacklist; 72 73 /* portable attributes, etc. */ 74 typedef struct Stat Stat; 75 76 struct Stat { 77 char *name; 78 char *long_name; 79 Attrib attrib; 80 }; 81 82 /* Packet handlers */ 83 static void process_open(u_int32_t id); 84 static void process_close(u_int32_t id); 85 static void process_read(u_int32_t id); 86 static void process_write(u_int32_t id); 87 static void process_stat(u_int32_t id); 88 static void process_lstat(u_int32_t id); 89 static void process_fstat(u_int32_t id); 90 static void process_setstat(u_int32_t id); 91 static void process_fsetstat(u_int32_t id); 92 static void process_opendir(u_int32_t id); 93 static void process_readdir(u_int32_t id); 94 static void process_remove(u_int32_t id); 95 static void process_mkdir(u_int32_t id); 96 static void process_rmdir(u_int32_t id); 97 static void process_realpath(u_int32_t id); 98 static void process_rename(u_int32_t id); 99 static void process_readlink(u_int32_t id); 100 static void process_symlink(u_int32_t id); 101 static void process_extended_posix_rename(u_int32_t id); 102 static void process_extended_statvfs(u_int32_t id); 103 static void process_extended_fstatvfs(u_int32_t id); 104 static void process_extended_hardlink(u_int32_t id); 105 static void process_extended_fsync(u_int32_t id); 106 static void process_extended(u_int32_t id); 107 108 struct sftp_handler { 109 const char *name; /* user-visible name for fine-grained perms */ 110 const char *ext_name; /* extended request name */ 111 u_int type; /* packet type, for non extended packets */ 112 void (*handler)(u_int32_t); 113 int does_write; /* if nonzero, banned for readonly mode */ 114 }; 115 116 struct sftp_handler handlers[] = { 117 /* NB. SSH2_FXP_OPEN does the readonly check in the handler itself */ 118 { "open", NULL, SSH2_FXP_OPEN, process_open, 0 }, 119 { "close", NULL, SSH2_FXP_CLOSE, process_close, 0 }, 120 { "read", NULL, SSH2_FXP_READ, process_read, 0 }, 121 { "write", NULL, SSH2_FXP_WRITE, process_write, 1 }, 122 { "lstat", NULL, SSH2_FXP_LSTAT, process_lstat, 0 }, 123 { "fstat", NULL, SSH2_FXP_FSTAT, process_fstat, 0 }, 124 { "setstat", NULL, SSH2_FXP_SETSTAT, process_setstat, 1 }, 125 { "fsetstat", NULL, SSH2_FXP_FSETSTAT, process_fsetstat, 1 }, 126 { "opendir", NULL, SSH2_FXP_OPENDIR, process_opendir, 0 }, 127 { "readdir", NULL, SSH2_FXP_READDIR, process_readdir, 0 }, 128 { "remove", NULL, SSH2_FXP_REMOVE, process_remove, 1 }, 129 { "mkdir", NULL, SSH2_FXP_MKDIR, process_mkdir, 1 }, 130 { "rmdir", NULL, SSH2_FXP_RMDIR, process_rmdir, 1 }, 131 { "realpath", NULL, SSH2_FXP_REALPATH, process_realpath, 0 }, 132 { "stat", NULL, SSH2_FXP_STAT, process_stat, 0 }, 133 { "rename", NULL, SSH2_FXP_RENAME, process_rename, 1 }, 134 { "readlink", NULL, SSH2_FXP_READLINK, process_readlink, 0 }, 135 { "symlink", NULL, SSH2_FXP_SYMLINK, process_symlink, 1 }, 136 { NULL, NULL, 0, NULL, 0 } 137 }; 138 139 /* SSH2_FXP_EXTENDED submessages */ 140 struct sftp_handler extended_handlers[] = { 141 { "posix-rename", "posix-rename@openssh.com", 0, 142 process_extended_posix_rename, 1 }, 143 { "statvfs", "statvfs@openssh.com", 0, process_extended_statvfs, 0 }, 144 { "fstatvfs", "fstatvfs@openssh.com", 0, process_extended_fstatvfs, 0 }, 145 { "hardlink", "hardlink@openssh.com", 0, process_extended_hardlink, 1 }, 146 { "fsync", "fsync@openssh.com", 0, process_extended_fsync, 1 }, 147 { NULL, NULL, 0, NULL, 0 } 148 }; 149 150 static int 151 request_permitted(struct sftp_handler *h) 152 { 153 char *result; 154 155 if (readonly && h->does_write) { 156 verbose("Refusing %s request in read-only mode", h->name); 157 return 0; 158 } 159 if (request_blacklist != NULL && 160 ((result = match_list(h->name, request_blacklist, NULL))) != NULL) { 161 free(result); 162 verbose("Refusing blacklisted %s request", h->name); 163 return 0; 164 } 165 if (request_whitelist != NULL && 166 ((result = match_list(h->name, request_whitelist, NULL))) != NULL) { 167 free(result); 168 debug2("Permitting whitelisted %s request", h->name); 169 return 1; 170 } 171 if (request_whitelist != NULL) { 172 verbose("Refusing non-whitelisted %s request", h->name); 173 return 0; 174 } 175 return 1; 176 } 177 178 static int 179 errno_to_portable(int unixerrno) 180 { 181 int ret = 0; 182 183 switch (unixerrno) { 184 case 0: 185 ret = SSH2_FX_OK; 186 break; 187 case ENOENT: 188 case ENOTDIR: 189 case EBADF: 190 case ELOOP: 191 ret = SSH2_FX_NO_SUCH_FILE; 192 break; 193 case EPERM: 194 case EACCES: 195 case EFAULT: 196 ret = SSH2_FX_PERMISSION_DENIED; 197 break; 198 case ENAMETOOLONG: 199 case EINVAL: 200 ret = SSH2_FX_BAD_MESSAGE; 201 break; 202 case ENOSYS: 203 ret = SSH2_FX_OP_UNSUPPORTED; 204 break; 205 default: 206 ret = SSH2_FX_FAILURE; 207 break; 208 } 209 return ret; 210 } 211 212 static int 213 flags_from_portable(int pflags) 214 { 215 int flags = 0; 216 217 if ((pflags & SSH2_FXF_READ) && 218 (pflags & SSH2_FXF_WRITE)) { 219 flags = O_RDWR; 220 } else if (pflags & SSH2_FXF_READ) { 221 flags = O_RDONLY; 222 } else if (pflags & SSH2_FXF_WRITE) { 223 flags = O_WRONLY; 224 } 225 if (pflags & SSH2_FXF_APPEND) 226 flags |= O_APPEND; 227 if (pflags & SSH2_FXF_CREAT) 228 flags |= O_CREAT; 229 if (pflags & SSH2_FXF_TRUNC) 230 flags |= O_TRUNC; 231 if (pflags & SSH2_FXF_EXCL) 232 flags |= O_EXCL; 233 return flags; 234 } 235 236 static const char * 237 string_from_portable(int pflags) 238 { 239 static char ret[128]; 240 241 *ret = '\0'; 242 243 #define PAPPEND(str) { \ 244 if (*ret != '\0') \ 245 strlcat(ret, ",", sizeof(ret)); \ 246 strlcat(ret, str, sizeof(ret)); \ 247 } 248 249 if (pflags & SSH2_FXF_READ) 250 PAPPEND("READ") 251 if (pflags & SSH2_FXF_WRITE) 252 PAPPEND("WRITE") 253 if (pflags & SSH2_FXF_APPEND) 254 PAPPEND("APPEND") 255 if (pflags & SSH2_FXF_CREAT) 256 PAPPEND("CREATE") 257 if (pflags & SSH2_FXF_TRUNC) 258 PAPPEND("TRUNCATE") 259 if (pflags & SSH2_FXF_EXCL) 260 PAPPEND("EXCL") 261 262 return ret; 263 } 264 265 /* handle handles */ 266 267 typedef struct Handle Handle; 268 struct Handle { 269 int use; 270 DIR *dirp; 271 int fd; 272 int flags; 273 char *name; 274 u_int64_t bytes_read, bytes_write; 275 int next_unused; 276 }; 277 278 enum { 279 HANDLE_UNUSED, 280 HANDLE_DIR, 281 HANDLE_FILE 282 }; 283 284 Handle *handles = NULL; 285 u_int num_handles = 0; 286 int first_unused_handle = -1; 287 288 static void handle_unused(int i) 289 { 290 handles[i].use = HANDLE_UNUSED; 291 handles[i].next_unused = first_unused_handle; 292 first_unused_handle = i; 293 } 294 295 static int 296 handle_new(int use, const char *name, int fd, int flags, DIR *dirp) 297 { 298 int i; 299 300 if (first_unused_handle == -1) { 301 if (num_handles + 1 <= num_handles) 302 return -1; 303 num_handles++; 304 handles = xreallocarray(handles, num_handles, sizeof(Handle)); 305 handle_unused(num_handles - 1); 306 } 307 308 i = first_unused_handle; 309 first_unused_handle = handles[i].next_unused; 310 311 handles[i].use = use; 312 handles[i].dirp = dirp; 313 handles[i].fd = fd; 314 handles[i].flags = flags; 315 handles[i].name = xstrdup(name); 316 handles[i].bytes_read = handles[i].bytes_write = 0; 317 318 return i; 319 } 320 321 static int 322 handle_is_ok(int i, int type) 323 { 324 return i >= 0 && (u_int)i < num_handles && handles[i].use == type; 325 } 326 327 static int 328 handle_to_string(int handle, u_char **stringp, int *hlenp) 329 { 330 if (stringp == NULL || hlenp == NULL) 331 return -1; 332 *stringp = xmalloc(sizeof(int32_t)); 333 put_u32(*stringp, handle); 334 *hlenp = sizeof(int32_t); 335 return 0; 336 } 337 338 static int 339 handle_from_string(const u_char *handle, u_int hlen) 340 { 341 int val; 342 343 if (hlen != sizeof(int32_t)) 344 return -1; 345 val = get_u32(handle); 346 if (handle_is_ok(val, HANDLE_FILE) || 347 handle_is_ok(val, HANDLE_DIR)) 348 return val; 349 return -1; 350 } 351 352 static char * 353 handle_to_name(int handle) 354 { 355 if (handle_is_ok(handle, HANDLE_DIR)|| 356 handle_is_ok(handle, HANDLE_FILE)) 357 return handles[handle].name; 358 return NULL; 359 } 360 361 static DIR * 362 handle_to_dir(int handle) 363 { 364 if (handle_is_ok(handle, HANDLE_DIR)) 365 return handles[handle].dirp; 366 return NULL; 367 } 368 369 static int 370 handle_to_fd(int handle) 371 { 372 if (handle_is_ok(handle, HANDLE_FILE)) 373 return handles[handle].fd; 374 return -1; 375 } 376 377 static int 378 handle_to_flags(int handle) 379 { 380 if (handle_is_ok(handle, HANDLE_FILE)) 381 return handles[handle].flags; 382 return 0; 383 } 384 385 static void 386 handle_update_read(int handle, ssize_t bytes) 387 { 388 if (handle_is_ok(handle, HANDLE_FILE) && bytes > 0) 389 handles[handle].bytes_read += bytes; 390 } 391 392 static void 393 handle_update_write(int handle, ssize_t bytes) 394 { 395 if (handle_is_ok(handle, HANDLE_FILE) && bytes > 0) 396 handles[handle].bytes_write += bytes; 397 } 398 399 static u_int64_t 400 handle_bytes_read(int handle) 401 { 402 if (handle_is_ok(handle, HANDLE_FILE)) 403 return (handles[handle].bytes_read); 404 return 0; 405 } 406 407 static u_int64_t 408 handle_bytes_write(int handle) 409 { 410 if (handle_is_ok(handle, HANDLE_FILE)) 411 return (handles[handle].bytes_write); 412 return 0; 413 } 414 415 static int 416 handle_close(int handle) 417 { 418 int ret = -1; 419 420 if (handle_is_ok(handle, HANDLE_FILE)) { 421 ret = close(handles[handle].fd); 422 free(handles[handle].name); 423 handle_unused(handle); 424 } else if (handle_is_ok(handle, HANDLE_DIR)) { 425 ret = closedir(handles[handle].dirp); 426 free(handles[handle].name); 427 handle_unused(handle); 428 } else { 429 errno = ENOENT; 430 } 431 return ret; 432 } 433 434 static void 435 handle_log_close(int handle, const char *emsg) 436 { 437 if (handle_is_ok(handle, HANDLE_FILE)) { 438 logit("%s%sclose \"%s\" bytes read %llu written %llu", 439 emsg == NULL ? "" : emsg, emsg == NULL ? "" : " ", 440 handle_to_name(handle), 441 (unsigned long long)handle_bytes_read(handle), 442 (unsigned long long)handle_bytes_write(handle)); 443 } else { 444 logit("%s%sclosedir \"%s\"", 445 emsg == NULL ? "" : emsg, emsg == NULL ? "" : " ", 446 handle_to_name(handle)); 447 } 448 } 449 450 static void 451 handle_log_exit(void) 452 { 453 u_int i; 454 455 for (i = 0; i < num_handles; i++) 456 if (handles[i].use != HANDLE_UNUSED) 457 handle_log_close(i, "forced"); 458 } 459 460 static int 461 get_handle(struct sshbuf *queue, int *hp) 462 { 463 u_char *handle; 464 int r; 465 size_t hlen; 466 467 *hp = -1; 468 if ((r = sshbuf_get_string(queue, &handle, &hlen)) != 0) 469 return r; 470 if (hlen < 256) 471 *hp = handle_from_string(handle, hlen); 472 free(handle); 473 return 0; 474 } 475 476 /* send replies */ 477 478 static void 479 send_msg(struct sshbuf *m) 480 { 481 int r; 482 483 if ((r = sshbuf_put_stringb(oqueue, m)) != 0) 484 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 485 sshbuf_reset(m); 486 } 487 488 static const char * 489 status_to_message(u_int32_t status) 490 { 491 const char *status_messages[] = { 492 "Success", /* SSH_FX_OK */ 493 "End of file", /* SSH_FX_EOF */ 494 "No such file", /* SSH_FX_NO_SUCH_FILE */ 495 "Permission denied", /* SSH_FX_PERMISSION_DENIED */ 496 "Failure", /* SSH_FX_FAILURE */ 497 "Bad message", /* SSH_FX_BAD_MESSAGE */ 498 "No connection", /* SSH_FX_NO_CONNECTION */ 499 "Connection lost", /* SSH_FX_CONNECTION_LOST */ 500 "Operation unsupported", /* SSH_FX_OP_UNSUPPORTED */ 501 "Unknown error" /* Others */ 502 }; 503 return (status_messages[MIN(status,SSH2_FX_MAX)]); 504 } 505 506 static void 507 send_status(u_int32_t id, u_int32_t status) 508 { 509 struct sshbuf *msg; 510 int r; 511 512 debug3("request %u: sent status %u", id, status); 513 if (log_level > SYSLOG_LEVEL_VERBOSE || 514 (status != SSH2_FX_OK && status != SSH2_FX_EOF)) 515 logit("sent status %s", status_to_message(status)); 516 if ((msg = sshbuf_new()) == NULL) 517 fatal("%s: sshbuf_new failed", __func__); 518 if ((r = sshbuf_put_u8(msg, SSH2_FXP_STATUS)) != 0 || 519 (r = sshbuf_put_u32(msg, id)) != 0 || 520 (r = sshbuf_put_u32(msg, status)) != 0) 521 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 522 if (version >= 3) { 523 if ((r = sshbuf_put_cstring(msg, 524 status_to_message(status))) != 0 || 525 (r = sshbuf_put_cstring(msg, "")) != 0) 526 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 527 } 528 send_msg(msg); 529 sshbuf_free(msg); 530 } 531 static void 532 send_data_or_handle(char type, u_int32_t id, const u_char *data, int dlen) 533 { 534 struct sshbuf *msg; 535 int r; 536 537 if ((msg = sshbuf_new()) == NULL) 538 fatal("%s: sshbuf_new failed", __func__); 539 if ((r = sshbuf_put_u8(msg, type)) != 0 || 540 (r = sshbuf_put_u32(msg, id)) != 0 || 541 (r = sshbuf_put_string(msg, data, dlen)) != 0) 542 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 543 send_msg(msg); 544 sshbuf_free(msg); 545 } 546 547 static void 548 send_data(u_int32_t id, const u_char *data, int dlen) 549 { 550 debug("request %u: sent data len %d", id, dlen); 551 send_data_or_handle(SSH2_FXP_DATA, id, data, dlen); 552 } 553 554 static void 555 send_handle(u_int32_t id, int handle) 556 { 557 u_char *string; 558 int hlen; 559 560 handle_to_string(handle, &string, &hlen); 561 debug("request %u: sent handle handle %d", id, handle); 562 send_data_or_handle(SSH2_FXP_HANDLE, id, string, hlen); 563 free(string); 564 } 565 566 static void 567 send_names(u_int32_t id, int count, const Stat *stats) 568 { 569 struct sshbuf *msg; 570 int i, r; 571 572 if ((msg = sshbuf_new()) == NULL) 573 fatal("%s: sshbuf_new failed", __func__); 574 if ((r = sshbuf_put_u8(msg, SSH2_FXP_NAME)) != 0 || 575 (r = sshbuf_put_u32(msg, id)) != 0 || 576 (r = sshbuf_put_u32(msg, count)) != 0) 577 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 578 debug("request %u: sent names count %d", id, count); 579 for (i = 0; i < count; i++) { 580 if ((r = sshbuf_put_cstring(msg, stats[i].name)) != 0 || 581 (r = sshbuf_put_cstring(msg, stats[i].long_name)) != 0 || 582 (r = encode_attrib(msg, &stats[i].attrib)) != 0) 583 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 584 } 585 send_msg(msg); 586 sshbuf_free(msg); 587 } 588 589 static void 590 send_attrib(u_int32_t id, const Attrib *a) 591 { 592 struct sshbuf *msg; 593 int r; 594 595 debug("request %u: sent attrib have 0x%x", id, a->flags); 596 if ((msg = sshbuf_new()) == NULL) 597 fatal("%s: sshbuf_new failed", __func__); 598 if ((r = sshbuf_put_u8(msg, SSH2_FXP_ATTRS)) != 0 || 599 (r = sshbuf_put_u32(msg, id)) != 0 || 600 (r = encode_attrib(msg, a)) != 0) 601 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 602 send_msg(msg); 603 sshbuf_free(msg); 604 } 605 606 static void 607 send_statvfs(u_int32_t id, struct statvfs *st) 608 { 609 struct sshbuf *msg; 610 u_int64_t flag; 611 int r; 612 613 flag = (st->f_flag & ST_RDONLY) ? SSH2_FXE_STATVFS_ST_RDONLY : 0; 614 flag |= (st->f_flag & ST_NOSUID) ? SSH2_FXE_STATVFS_ST_NOSUID : 0; 615 616 if ((msg = sshbuf_new()) == NULL) 617 fatal("%s: sshbuf_new failed", __func__); 618 if ((r = sshbuf_put_u8(msg, SSH2_FXP_EXTENDED_REPLY)) != 0 || 619 (r = sshbuf_put_u32(msg, id)) != 0 || 620 (r = sshbuf_put_u64(msg, st->f_bsize)) != 0 || 621 (r = sshbuf_put_u64(msg, st->f_frsize)) != 0 || 622 (r = sshbuf_put_u64(msg, st->f_blocks)) != 0 || 623 (r = sshbuf_put_u64(msg, st->f_bfree)) != 0 || 624 (r = sshbuf_put_u64(msg, st->f_bavail)) != 0 || 625 (r = sshbuf_put_u64(msg, st->f_files)) != 0 || 626 (r = sshbuf_put_u64(msg, st->f_ffree)) != 0 || 627 (r = sshbuf_put_u64(msg, st->f_favail)) != 0 || 628 (r = sshbuf_put_u64(msg, st->f_fsid)) != 0 || 629 (r = sshbuf_put_u64(msg, flag)) != 0 || 630 (r = sshbuf_put_u64(msg, st->f_namemax)) != 0) 631 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 632 send_msg(msg); 633 sshbuf_free(msg); 634 } 635 636 /* parse incoming */ 637 638 static void 639 process_init(void) 640 { 641 struct sshbuf *msg; 642 int r; 643 644 if ((r = sshbuf_get_u32(iqueue, &version)) != 0) 645 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 646 verbose("received client version %u", version); 647 if ((msg = sshbuf_new()) == NULL) 648 fatal("%s: sshbuf_new failed", __func__); 649 if ((r = sshbuf_put_u8(msg, SSH2_FXP_VERSION)) != 0 || 650 (r = sshbuf_put_u32(msg, SSH2_FILEXFER_VERSION)) != 0 || 651 /* POSIX rename extension */ 652 (r = sshbuf_put_cstring(msg, "posix-rename@openssh.com")) != 0 || 653 (r = sshbuf_put_cstring(msg, "1")) != 0 || /* version */ 654 /* statvfs extension */ 655 (r = sshbuf_put_cstring(msg, "statvfs@openssh.com")) != 0 || 656 (r = sshbuf_put_cstring(msg, "2")) != 0 || /* version */ 657 /* fstatvfs extension */ 658 (r = sshbuf_put_cstring(msg, "fstatvfs@openssh.com")) != 0 || 659 (r = sshbuf_put_cstring(msg, "2")) != 0 || /* version */ 660 /* hardlink extension */ 661 (r = sshbuf_put_cstring(msg, "hardlink@openssh.com")) != 0 || 662 (r = sshbuf_put_cstring(msg, "1")) != 0 || /* version */ 663 /* fsync extension */ 664 (r = sshbuf_put_cstring(msg, "fsync@openssh.com")) != 0 || 665 (r = sshbuf_put_cstring(msg, "1")) != 0) /* version */ 666 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 667 send_msg(msg); 668 sshbuf_free(msg); 669 } 670 671 static void 672 process_open(u_int32_t id) 673 { 674 u_int32_t pflags; 675 Attrib a; 676 char *name; 677 int r, handle, fd, flags, mode, status = SSH2_FX_FAILURE; 678 679 if ((r = sshbuf_get_cstring(iqueue, &name, NULL)) != 0 || 680 (r = sshbuf_get_u32(iqueue, &pflags)) != 0 || /* portable flags */ 681 (r = decode_attrib(iqueue, &a)) != 0) 682 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 683 684 debug3("request %u: open flags %d", id, pflags); 685 flags = flags_from_portable(pflags); 686 mode = (a.flags & SSH2_FILEXFER_ATTR_PERMISSIONS) ? a.perm : 0666; 687 logit("open \"%s\" flags %s mode 0%o", 688 name, string_from_portable(pflags), mode); 689 if (readonly && 690 ((flags & O_ACCMODE) == O_WRONLY || 691 (flags & O_ACCMODE) == O_RDWR)) { 692 verbose("Refusing open request in read-only mode"); 693 status = SSH2_FX_PERMISSION_DENIED; 694 } else { 695 fd = open(name, flags, mode); 696 if (fd < 0) { 697 status = errno_to_portable(errno); 698 } else { 699 handle = handle_new(HANDLE_FILE, name, fd, flags, NULL); 700 if (handle < 0) { 701 close(fd); 702 } else { 703 send_handle(id, handle); 704 status = SSH2_FX_OK; 705 } 706 } 707 } 708 if (status != SSH2_FX_OK) 709 send_status(id, status); 710 free(name); 711 } 712 713 static void 714 process_close(u_int32_t id) 715 { 716 int r, handle, ret, status = SSH2_FX_FAILURE; 717 718 if ((r = get_handle(iqueue, &handle)) != 0) 719 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 720 721 debug3("request %u: close handle %u", id, handle); 722 handle_log_close(handle, NULL); 723 ret = handle_close(handle); 724 status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK; 725 send_status(id, status); 726 } 727 728 static void 729 process_read(u_int32_t id) 730 { 731 u_char buf[64*1024]; 732 u_int32_t len; 733 int r, handle, fd, ret, status = SSH2_FX_FAILURE; 734 u_int64_t off; 735 736 if ((r = get_handle(iqueue, &handle)) != 0 || 737 (r = sshbuf_get_u64(iqueue, &off)) != 0 || 738 (r = sshbuf_get_u32(iqueue, &len)) != 0) 739 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 740 741 debug("request %u: read \"%s\" (handle %d) off %llu len %d", 742 id, handle_to_name(handle), handle, (unsigned long long)off, len); 743 if (len > sizeof buf) { 744 len = sizeof buf; 745 debug2("read change len %d", len); 746 } 747 fd = handle_to_fd(handle); 748 if (fd >= 0) { 749 if (lseek(fd, off, SEEK_SET) < 0) { 750 error("process_read: seek failed"); 751 status = errno_to_portable(errno); 752 } else { 753 ret = read(fd, buf, len); 754 if (ret < 0) { 755 status = errno_to_portable(errno); 756 } else if (ret == 0) { 757 status = SSH2_FX_EOF; 758 } else { 759 send_data(id, buf, ret); 760 status = SSH2_FX_OK; 761 handle_update_read(handle, ret); 762 } 763 } 764 } 765 if (status != SSH2_FX_OK) 766 send_status(id, status); 767 } 768 769 static void 770 process_write(u_int32_t id) 771 { 772 u_int64_t off; 773 size_t len; 774 int r, handle, fd, ret, status; 775 u_char *data; 776 777 if ((r = get_handle(iqueue, &handle)) != 0 || 778 (r = sshbuf_get_u64(iqueue, &off)) != 0 || 779 (r = sshbuf_get_string(iqueue, &data, &len)) != 0) 780 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 781 782 debug("request %u: write \"%s\" (handle %d) off %llu len %zu", 783 id, handle_to_name(handle), handle, (unsigned long long)off, len); 784 fd = handle_to_fd(handle); 785 786 if (fd < 0) 787 status = SSH2_FX_FAILURE; 788 else { 789 if (!(handle_to_flags(handle) & O_APPEND) && 790 lseek(fd, off, SEEK_SET) < 0) { 791 status = errno_to_portable(errno); 792 error("process_write: seek failed"); 793 } else { 794 /* XXX ATOMICIO ? */ 795 ret = write(fd, data, len); 796 if (ret < 0) { 797 error("process_write: write failed"); 798 status = errno_to_portable(errno); 799 } else if ((size_t)ret == len) { 800 status = SSH2_FX_OK; 801 handle_update_write(handle, ret); 802 } else { 803 debug2("nothing at all written"); 804 status = SSH2_FX_FAILURE; 805 } 806 } 807 } 808 send_status(id, status); 809 free(data); 810 } 811 812 static void 813 process_do_stat(u_int32_t id, int do_lstat) 814 { 815 Attrib a; 816 struct stat st; 817 char *name; 818 int r, status = SSH2_FX_FAILURE; 819 820 if ((r = sshbuf_get_cstring(iqueue, &name, NULL)) != 0) 821 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 822 823 debug3("request %u: %sstat", id, do_lstat ? "l" : ""); 824 verbose("%sstat name \"%s\"", do_lstat ? "l" : "", name); 825 r = do_lstat ? lstat(name, &st) : stat(name, &st); 826 if (r < 0) { 827 status = errno_to_portable(errno); 828 } else { 829 stat_to_attrib(&st, &a); 830 send_attrib(id, &a); 831 status = SSH2_FX_OK; 832 } 833 if (status != SSH2_FX_OK) 834 send_status(id, status); 835 free(name); 836 } 837 838 static void 839 process_stat(u_int32_t id) 840 { 841 process_do_stat(id, 0); 842 } 843 844 static void 845 process_lstat(u_int32_t id) 846 { 847 process_do_stat(id, 1); 848 } 849 850 static void 851 process_fstat(u_int32_t id) 852 { 853 Attrib a; 854 struct stat st; 855 int fd, r, handle, status = SSH2_FX_FAILURE; 856 857 if ((r = get_handle(iqueue, &handle)) != 0) 858 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 859 debug("request %u: fstat \"%s\" (handle %u)", 860 id, handle_to_name(handle), handle); 861 fd = handle_to_fd(handle); 862 if (fd >= 0) { 863 r = fstat(fd, &st); 864 if (r < 0) { 865 status = errno_to_portable(errno); 866 } else { 867 stat_to_attrib(&st, &a); 868 send_attrib(id, &a); 869 status = SSH2_FX_OK; 870 } 871 } 872 if (status != SSH2_FX_OK) 873 send_status(id, status); 874 } 875 876 static struct timeval * 877 attrib_to_tv(const Attrib *a) 878 { 879 static struct timeval tv[2]; 880 881 tv[0].tv_sec = a->atime; 882 tv[0].tv_usec = 0; 883 tv[1].tv_sec = a->mtime; 884 tv[1].tv_usec = 0; 885 return tv; 886 } 887 888 static void 889 process_setstat(u_int32_t id) 890 { 891 Attrib a; 892 char *name; 893 int r, status = SSH2_FX_OK; 894 895 if ((r = sshbuf_get_cstring(iqueue, &name, NULL)) != 0 || 896 (r = decode_attrib(iqueue, &a)) != 0) 897 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 898 899 debug("request %u: setstat name \"%s\"", id, name); 900 if (a.flags & SSH2_FILEXFER_ATTR_SIZE) { 901 logit("set \"%s\" size %llu", 902 name, (unsigned long long)a.size); 903 r = truncate(name, a.size); 904 if (r == -1) 905 status = errno_to_portable(errno); 906 } 907 if (a.flags & SSH2_FILEXFER_ATTR_PERMISSIONS) { 908 logit("set \"%s\" mode %04o", name, a.perm); 909 r = chmod(name, a.perm & 07777); 910 if (r == -1) 911 status = errno_to_portable(errno); 912 } 913 if (a.flags & SSH2_FILEXFER_ATTR_ACMODTIME) { 914 char buf[64]; 915 time_t t = a.mtime; 916 917 strftime(buf, sizeof(buf), "%Y%m%d-%H:%M:%S", 918 localtime(&t)); 919 logit("set \"%s\" modtime %s", name, buf); 920 r = utimes(name, attrib_to_tv(&a)); 921 if (r == -1) 922 status = errno_to_portable(errno); 923 } 924 if (a.flags & SSH2_FILEXFER_ATTR_UIDGID) { 925 logit("set \"%s\" owner %lu group %lu", name, 926 (u_long)a.uid, (u_long)a.gid); 927 r = chown(name, a.uid, a.gid); 928 if (r == -1) 929 status = errno_to_portable(errno); 930 } 931 send_status(id, status); 932 free(name); 933 } 934 935 static void 936 process_fsetstat(u_int32_t id) 937 { 938 Attrib a; 939 int handle, fd, r; 940 int status = SSH2_FX_OK; 941 942 if ((r = get_handle(iqueue, &handle)) != 0 || 943 (r = decode_attrib(iqueue, &a)) != 0) 944 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 945 946 debug("request %u: fsetstat handle %d", id, handle); 947 fd = handle_to_fd(handle); 948 if (fd < 0) 949 status = SSH2_FX_FAILURE; 950 else { 951 char *name = handle_to_name(handle); 952 953 if (a.flags & SSH2_FILEXFER_ATTR_SIZE) { 954 logit("set \"%s\" size %llu", 955 name, (unsigned long long)a.size); 956 r = ftruncate(fd, a.size); 957 if (r == -1) 958 status = errno_to_portable(errno); 959 } 960 if (a.flags & SSH2_FILEXFER_ATTR_PERMISSIONS) { 961 logit("set \"%s\" mode %04o", name, a.perm); 962 r = fchmod(fd, a.perm & 07777); 963 if (r == -1) 964 status = errno_to_portable(errno); 965 } 966 if (a.flags & SSH2_FILEXFER_ATTR_ACMODTIME) { 967 char buf[64]; 968 time_t t = a.mtime; 969 970 strftime(buf, sizeof(buf), "%Y%m%d-%H:%M:%S", 971 localtime(&t)); 972 logit("set \"%s\" modtime %s", name, buf); 973 r = futimes(fd, attrib_to_tv(&a)); 974 if (r == -1) 975 status = errno_to_portable(errno); 976 } 977 if (a.flags & SSH2_FILEXFER_ATTR_UIDGID) { 978 logit("set \"%s\" owner %lu group %lu", name, 979 (u_long)a.uid, (u_long)a.gid); 980 r = fchown(fd, a.uid, a.gid); 981 if (r == -1) 982 status = errno_to_portable(errno); 983 } 984 } 985 send_status(id, status); 986 } 987 988 static void 989 process_opendir(u_int32_t id) 990 { 991 DIR *dirp = NULL; 992 char *path; 993 int r, handle, status = SSH2_FX_FAILURE; 994 995 if ((r = sshbuf_get_cstring(iqueue, &path, NULL)) != 0) 996 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 997 998 debug3("request %u: opendir", id); 999 logit("opendir \"%s\"", path); 1000 dirp = opendir(path); 1001 if (dirp == NULL) { 1002 status = errno_to_portable(errno); 1003 } else { 1004 handle = handle_new(HANDLE_DIR, path, 0, 0, dirp); 1005 if (handle < 0) { 1006 closedir(dirp); 1007 } else { 1008 send_handle(id, handle); 1009 status = SSH2_FX_OK; 1010 } 1011 1012 } 1013 if (status != SSH2_FX_OK) 1014 send_status(id, status); 1015 free(path); 1016 } 1017 1018 static void 1019 process_readdir(u_int32_t id) 1020 { 1021 DIR *dirp; 1022 struct dirent *dp; 1023 char *path; 1024 int r, handle; 1025 1026 if ((r = get_handle(iqueue, &handle)) != 0) 1027 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1028 1029 debug("request %u: readdir \"%s\" (handle %d)", id, 1030 handle_to_name(handle), handle); 1031 dirp = handle_to_dir(handle); 1032 path = handle_to_name(handle); 1033 if (dirp == NULL || path == NULL) { 1034 send_status(id, SSH2_FX_FAILURE); 1035 } else { 1036 struct stat st; 1037 char pathname[PATH_MAX]; 1038 Stat *stats; 1039 int nstats = 10, count = 0, i; 1040 1041 stats = xcalloc(nstats, sizeof(Stat)); 1042 while ((dp = readdir(dirp)) != NULL) { 1043 if (count >= nstats) { 1044 nstats *= 2; 1045 stats = xreallocarray(stats, nstats, sizeof(Stat)); 1046 } 1047 /* XXX OVERFLOW ? */ 1048 snprintf(pathname, sizeof pathname, "%s%s%s", path, 1049 strcmp(path, "/") ? "/" : "", dp->d_name); 1050 if (lstat(pathname, &st) < 0) 1051 continue; 1052 stat_to_attrib(&st, &(stats[count].attrib)); 1053 stats[count].name = xstrdup(dp->d_name); 1054 stats[count].long_name = ls_file(dp->d_name, &st, 0, 0); 1055 count++; 1056 /* send up to 100 entries in one message */ 1057 /* XXX check packet size instead */ 1058 if (count == 100) 1059 break; 1060 } 1061 if (count > 0) { 1062 send_names(id, count, stats); 1063 for (i = 0; i < count; i++) { 1064 free(stats[i].name); 1065 free(stats[i].long_name); 1066 } 1067 } else { 1068 send_status(id, SSH2_FX_EOF); 1069 } 1070 free(stats); 1071 } 1072 } 1073 1074 static void 1075 process_remove(u_int32_t id) 1076 { 1077 char *name; 1078 int r, status = SSH2_FX_FAILURE; 1079 1080 if ((r = sshbuf_get_cstring(iqueue, &name, NULL)) != 0) 1081 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1082 1083 debug3("request %u: remove", id); 1084 logit("remove name \"%s\"", name); 1085 r = unlink(name); 1086 status = (r == -1) ? errno_to_portable(errno) : SSH2_FX_OK; 1087 send_status(id, status); 1088 free(name); 1089 } 1090 1091 static void 1092 process_mkdir(u_int32_t id) 1093 { 1094 Attrib a; 1095 char *name; 1096 int r, mode, status = SSH2_FX_FAILURE; 1097 1098 if ((r = sshbuf_get_cstring(iqueue, &name, NULL)) != 0 || 1099 (r = decode_attrib(iqueue, &a)) != 0) 1100 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1101 1102 mode = (a.flags & SSH2_FILEXFER_ATTR_PERMISSIONS) ? 1103 a.perm & 07777 : 0777; 1104 debug3("request %u: mkdir", id); 1105 logit("mkdir name \"%s\" mode 0%o", name, mode); 1106 r = mkdir(name, mode); 1107 status = (r == -1) ? errno_to_portable(errno) : SSH2_FX_OK; 1108 send_status(id, status); 1109 free(name); 1110 } 1111 1112 static void 1113 process_rmdir(u_int32_t id) 1114 { 1115 char *name; 1116 int r, status; 1117 1118 if ((r = sshbuf_get_cstring(iqueue, &name, NULL)) != 0) 1119 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1120 1121 debug3("request %u: rmdir", id); 1122 logit("rmdir name \"%s\"", name); 1123 r = rmdir(name); 1124 status = (r == -1) ? errno_to_portable(errno) : SSH2_FX_OK; 1125 send_status(id, status); 1126 free(name); 1127 } 1128 1129 static void 1130 process_realpath(u_int32_t id) 1131 { 1132 char resolvedname[PATH_MAX]; 1133 char *path; 1134 int r; 1135 1136 if ((r = sshbuf_get_cstring(iqueue, &path, NULL)) != 0) 1137 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1138 1139 if (path[0] == '\0') { 1140 free(path); 1141 path = xstrdup("."); 1142 } 1143 debug3("request %u: realpath", id); 1144 verbose("realpath \"%s\"", path); 1145 if (realpath(path, resolvedname) == NULL) { 1146 send_status(id, errno_to_portable(errno)); 1147 } else { 1148 Stat s; 1149 attrib_clear(&s.attrib); 1150 s.name = s.long_name = resolvedname; 1151 send_names(id, 1, &s); 1152 } 1153 free(path); 1154 } 1155 1156 static void 1157 process_rename(u_int32_t id) 1158 { 1159 char *oldpath, *newpath; 1160 int r, status; 1161 struct stat sb; 1162 1163 if ((r = sshbuf_get_cstring(iqueue, &oldpath, NULL)) != 0 || 1164 (r = sshbuf_get_cstring(iqueue, &newpath, NULL)) != 0) 1165 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1166 1167 debug3("request %u: rename", id); 1168 logit("rename old \"%s\" new \"%s\"", oldpath, newpath); 1169 status = SSH2_FX_FAILURE; 1170 if (lstat(oldpath, &sb) == -1) 1171 status = errno_to_portable(errno); 1172 else if (S_ISREG(sb.st_mode)) { 1173 /* Race-free rename of regular files */ 1174 if (link(oldpath, newpath) == -1) { 1175 if (errno == EOPNOTSUPP) { 1176 struct stat st; 1177 1178 /* 1179 * fs doesn't support links, so fall back to 1180 * stat+rename. This is racy. 1181 */ 1182 if (stat(newpath, &st) == -1) { 1183 if (rename(oldpath, newpath) == -1) 1184 status = 1185 errno_to_portable(errno); 1186 else 1187 status = SSH2_FX_OK; 1188 } 1189 } else { 1190 status = errno_to_portable(errno); 1191 } 1192 } else if (unlink(oldpath) == -1) { 1193 status = errno_to_portable(errno); 1194 /* clean spare link */ 1195 unlink(newpath); 1196 } else 1197 status = SSH2_FX_OK; 1198 } else if (stat(newpath, &sb) == -1) { 1199 if (rename(oldpath, newpath) == -1) 1200 status = errno_to_portable(errno); 1201 else 1202 status = SSH2_FX_OK; 1203 } 1204 send_status(id, status); 1205 free(oldpath); 1206 free(newpath); 1207 } 1208 1209 static void 1210 process_readlink(u_int32_t id) 1211 { 1212 int r, len; 1213 char buf[PATH_MAX]; 1214 char *path; 1215 1216 if ((r = sshbuf_get_cstring(iqueue, &path, NULL)) != 0) 1217 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1218 1219 debug3("request %u: readlink", id); 1220 verbose("readlink \"%s\"", path); 1221 if ((len = readlink(path, buf, sizeof(buf) - 1)) == -1) 1222 send_status(id, errno_to_portable(errno)); 1223 else { 1224 Stat s; 1225 1226 buf[len] = '\0'; 1227 attrib_clear(&s.attrib); 1228 s.name = s.long_name = buf; 1229 send_names(id, 1, &s); 1230 } 1231 free(path); 1232 } 1233 1234 static void 1235 process_symlink(u_int32_t id) 1236 { 1237 char *oldpath, *newpath; 1238 int r, status; 1239 1240 if ((r = sshbuf_get_cstring(iqueue, &oldpath, NULL)) != 0 || 1241 (r = sshbuf_get_cstring(iqueue, &newpath, NULL)) != 0) 1242 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1243 1244 debug3("request %u: symlink", id); 1245 logit("symlink old \"%s\" new \"%s\"", oldpath, newpath); 1246 /* this will fail if 'newpath' exists */ 1247 r = symlink(oldpath, newpath); 1248 status = (r == -1) ? errno_to_portable(errno) : SSH2_FX_OK; 1249 send_status(id, status); 1250 free(oldpath); 1251 free(newpath); 1252 } 1253 1254 static void 1255 process_extended_posix_rename(u_int32_t id) 1256 { 1257 char *oldpath, *newpath; 1258 int r, status; 1259 1260 if ((r = sshbuf_get_cstring(iqueue, &oldpath, NULL)) != 0 || 1261 (r = sshbuf_get_cstring(iqueue, &newpath, NULL)) != 0) 1262 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1263 1264 debug3("request %u: posix-rename", id); 1265 logit("posix-rename old \"%s\" new \"%s\"", oldpath, newpath); 1266 r = rename(oldpath, newpath); 1267 status = (r == -1) ? errno_to_portable(errno) : SSH2_FX_OK; 1268 send_status(id, status); 1269 free(oldpath); 1270 free(newpath); 1271 } 1272 1273 static void 1274 process_extended_statvfs(u_int32_t id) 1275 { 1276 char *path; 1277 struct statvfs st; 1278 int r; 1279 1280 if ((r = sshbuf_get_cstring(iqueue, &path, NULL)) != 0) 1281 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1282 debug3("request %u: statvfs", id); 1283 logit("statvfs \"%s\"", path); 1284 1285 if (statvfs(path, &st) != 0) 1286 send_status(id, errno_to_portable(errno)); 1287 else 1288 send_statvfs(id, &st); 1289 free(path); 1290 } 1291 1292 static void 1293 process_extended_fstatvfs(u_int32_t id) 1294 { 1295 int r, handle, fd; 1296 struct statvfs st; 1297 1298 if ((r = get_handle(iqueue, &handle)) != 0) 1299 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1300 debug("request %u: fstatvfs \"%s\" (handle %u)", 1301 id, handle_to_name(handle), handle); 1302 if ((fd = handle_to_fd(handle)) < 0) { 1303 send_status(id, SSH2_FX_FAILURE); 1304 return; 1305 } 1306 if (fstatvfs(fd, &st) != 0) 1307 send_status(id, errno_to_portable(errno)); 1308 else 1309 send_statvfs(id, &st); 1310 } 1311 1312 static void 1313 process_extended_hardlink(u_int32_t id) 1314 { 1315 char *oldpath, *newpath; 1316 int r, status; 1317 1318 if ((r = sshbuf_get_cstring(iqueue, &oldpath, NULL)) != 0 || 1319 (r = sshbuf_get_cstring(iqueue, &newpath, NULL)) != 0) 1320 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1321 1322 debug3("request %u: hardlink", id); 1323 logit("hardlink old \"%s\" new \"%s\"", oldpath, newpath); 1324 r = link(oldpath, newpath); 1325 status = (r == -1) ? errno_to_portable(errno) : SSH2_FX_OK; 1326 send_status(id, status); 1327 free(oldpath); 1328 free(newpath); 1329 } 1330 1331 static void 1332 process_extended_fsync(u_int32_t id) 1333 { 1334 int handle, fd, r, status = SSH2_FX_OP_UNSUPPORTED; 1335 1336 if ((r = get_handle(iqueue, &handle)) != 0) 1337 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1338 debug3("request %u: fsync (handle %u)", id, handle); 1339 verbose("fsync \"%s\"", handle_to_name(handle)); 1340 if ((fd = handle_to_fd(handle)) < 0) 1341 status = SSH2_FX_NO_SUCH_FILE; 1342 else if (handle_is_ok(handle, HANDLE_FILE)) { 1343 r = fsync(fd); 1344 status = (r == -1) ? errno_to_portable(errno) : SSH2_FX_OK; 1345 } 1346 send_status(id, status); 1347 } 1348 1349 static void 1350 process_extended(u_int32_t id) 1351 { 1352 char *request; 1353 int i, r; 1354 1355 if ((r = sshbuf_get_cstring(iqueue, &request, NULL)) != 0) 1356 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1357 for (i = 0; extended_handlers[i].handler != NULL; i++) { 1358 if (strcmp(request, extended_handlers[i].ext_name) == 0) { 1359 if (!request_permitted(&extended_handlers[i])) 1360 send_status(id, SSH2_FX_PERMISSION_DENIED); 1361 else 1362 extended_handlers[i].handler(id); 1363 break; 1364 } 1365 } 1366 if (extended_handlers[i].handler == NULL) { 1367 error("Unknown extended request \"%.100s\"", request); 1368 send_status(id, SSH2_FX_OP_UNSUPPORTED); /* MUST */ 1369 } 1370 free(request); 1371 } 1372 1373 /* stolen from ssh-agent */ 1374 1375 static void 1376 process(void) 1377 { 1378 u_int msg_len; 1379 u_int buf_len; 1380 u_int consumed; 1381 u_char type; 1382 const u_char *cp; 1383 int i, r; 1384 u_int32_t id; 1385 1386 buf_len = sshbuf_len(iqueue); 1387 if (buf_len < 5) 1388 return; /* Incomplete message. */ 1389 cp = sshbuf_ptr(iqueue); 1390 msg_len = get_u32(cp); 1391 if (msg_len > SFTP_MAX_MSG_LENGTH) { 1392 error("bad message from %s local user %s", 1393 client_addr, pw->pw_name); 1394 sftp_server_cleanup_exit(11); 1395 } 1396 if (buf_len < msg_len + 4) 1397 return; 1398 if ((r = sshbuf_consume(iqueue, 4)) != 0) 1399 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1400 buf_len -= 4; 1401 if ((r = sshbuf_get_u8(iqueue, &type)) != 0) 1402 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1403 1404 switch (type) { 1405 case SSH2_FXP_INIT: 1406 process_init(); 1407 init_done = 1; 1408 break; 1409 case SSH2_FXP_EXTENDED: 1410 if (!init_done) 1411 fatal("Received extended request before init"); 1412 if ((r = sshbuf_get_u32(iqueue, &id)) != 0) 1413 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1414 process_extended(id); 1415 break; 1416 default: 1417 if (!init_done) 1418 fatal("Received %u request before init", type); 1419 if ((r = sshbuf_get_u32(iqueue, &id)) != 0) 1420 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1421 for (i = 0; handlers[i].handler != NULL; i++) { 1422 if (type == handlers[i].type) { 1423 if (!request_permitted(&handlers[i])) { 1424 send_status(id, 1425 SSH2_FX_PERMISSION_DENIED); 1426 } else { 1427 handlers[i].handler(id); 1428 } 1429 break; 1430 } 1431 } 1432 if (handlers[i].handler == NULL) 1433 error("Unknown message %u", type); 1434 } 1435 /* discard the remaining bytes from the current packet */ 1436 if (buf_len < sshbuf_len(iqueue)) { 1437 error("iqueue grew unexpectedly"); 1438 sftp_server_cleanup_exit(255); 1439 } 1440 consumed = buf_len - sshbuf_len(iqueue); 1441 if (msg_len < consumed) { 1442 error("msg_len %u < consumed %u", msg_len, consumed); 1443 sftp_server_cleanup_exit(255); 1444 } 1445 if (msg_len > consumed && 1446 (r = sshbuf_consume(iqueue, msg_len - consumed)) != 0) 1447 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1448 } 1449 1450 /* Cleanup handler that logs active handles upon normal exit */ 1451 void 1452 sftp_server_cleanup_exit(int i) 1453 { 1454 if (pw != NULL && client_addr != NULL) { 1455 handle_log_exit(); 1456 logit("session closed for local user %s from [%s]", 1457 pw->pw_name, client_addr); 1458 } 1459 _exit(i); 1460 } 1461 1462 __dead static void 1463 sftp_server_usage(void) 1464 { 1465 extern char *__progname; 1466 1467 fprintf(stderr, 1468 "usage: %s [-ehR] [-d start_directory] [-f log_facility] " 1469 "[-l log_level]\n\t[-P blacklisted_requests] " 1470 "[-p whitelisted_requests] [-u umask]\n" 1471 " %s -Q protocol_feature\n", 1472 __progname, __progname); 1473 exit(1); 1474 } 1475 1476 int 1477 sftp_server_main(int argc, char **argv, struct passwd *user_pw) 1478 { 1479 fd_set *rset, *wset; 1480 int i, r, in, out, max, ch, skipargs = 0, log_stderr = 0; 1481 ssize_t len, olen, set_size; 1482 SyslogFacility log_facility = SYSLOG_FACILITY_AUTH; 1483 char *cp, *homedir = NULL, buf[4*4096]; 1484 long mask; 1485 1486 extern char *optarg; 1487 extern char *__progname; 1488 1489 log_init(__progname, log_level, log_facility, log_stderr); 1490 1491 pw = pwcopy(user_pw); 1492 1493 while (!skipargs && (ch = getopt(argc, argv, 1494 "d:f:l:P:p:Q:u:cehR")) != -1) { 1495 switch (ch) { 1496 case 'Q': 1497 if (strcasecmp(optarg, "requests") != 0) { 1498 fprintf(stderr, "Invalid query type\n"); 1499 exit(1); 1500 } 1501 for (i = 0; handlers[i].handler != NULL; i++) 1502 printf("%s\n", handlers[i].name); 1503 for (i = 0; extended_handlers[i].handler != NULL; i++) 1504 printf("%s\n", extended_handlers[i].name); 1505 exit(0); 1506 break; 1507 case 'R': 1508 readonly = 1; 1509 break; 1510 case 'c': 1511 /* 1512 * Ignore all arguments if we are invoked as a 1513 * shell using "sftp-server -c command" 1514 */ 1515 skipargs = 1; 1516 break; 1517 case 'e': 1518 log_stderr = 1; 1519 break; 1520 case 'l': 1521 log_level = log_level_number(optarg); 1522 if (log_level == SYSLOG_LEVEL_NOT_SET) 1523 error("Invalid log level \"%s\"", optarg); 1524 break; 1525 case 'f': 1526 log_facility = log_facility_number(optarg); 1527 if (log_facility == SYSLOG_FACILITY_NOT_SET) 1528 error("Invalid log facility \"%s\"", optarg); 1529 break; 1530 case 'd': 1531 cp = tilde_expand_filename(optarg, user_pw->pw_uid); 1532 homedir = percent_expand(cp, "d", user_pw->pw_dir, 1533 "u", user_pw->pw_name, (char *)NULL); 1534 free(cp); 1535 break; 1536 case 'p': 1537 if (request_whitelist != NULL) 1538 fatal("Permitted requests already set"); 1539 request_whitelist = xstrdup(optarg); 1540 break; 1541 case 'P': 1542 if (request_blacklist != NULL) 1543 fatal("Refused requests already set"); 1544 request_blacklist = xstrdup(optarg); 1545 break; 1546 case 'u': 1547 errno = 0; 1548 mask = strtol(optarg, &cp, 8); 1549 if (mask < 0 || mask > 0777 || *cp != '\0' || 1550 cp == optarg || (mask == 0 && errno != 0)) 1551 fatal("Invalid umask \"%s\"", optarg); 1552 (void)umask((mode_t)mask); 1553 break; 1554 case 'h': 1555 default: 1556 sftp_server_usage(); 1557 } 1558 } 1559 1560 log_init(__progname, log_level, log_facility, log_stderr); 1561 1562 if ((cp = getenv("SSH_CONNECTION")) != NULL) { 1563 client_addr = xstrdup(cp); 1564 if ((cp = strchr(client_addr, ' ')) == NULL) { 1565 error("Malformed SSH_CONNECTION variable: \"%s\"", 1566 getenv("SSH_CONNECTION")); 1567 sftp_server_cleanup_exit(255); 1568 } 1569 *cp = '\0'; 1570 } else 1571 client_addr = xstrdup("UNKNOWN"); 1572 1573 logit("session opened for local user %s from [%s]", 1574 pw->pw_name, client_addr); 1575 1576 in = STDIN_FILENO; 1577 out = STDOUT_FILENO; 1578 1579 max = 0; 1580 if (in > max) 1581 max = in; 1582 if (out > max) 1583 max = out; 1584 1585 if ((iqueue = sshbuf_new()) == NULL) 1586 fatal("%s: sshbuf_new failed", __func__); 1587 if ((oqueue = sshbuf_new()) == NULL) 1588 fatal("%s: sshbuf_new failed", __func__); 1589 1590 set_size = howmany(max + 1, NFDBITS) * sizeof(fd_mask); 1591 rset = (fd_set *)xmalloc(set_size); 1592 wset = (fd_set *)xmalloc(set_size); 1593 1594 if (homedir != NULL) { 1595 if (chdir(homedir) != 0) { 1596 error("chdir to \"%s\" failed: %s", homedir, 1597 strerror(errno)); 1598 } 1599 } 1600 1601 for (;;) { 1602 memset(rset, 0, set_size); 1603 memset(wset, 0, set_size); 1604 1605 /* 1606 * Ensure that we can read a full buffer and handle 1607 * the worst-case length packet it can generate, 1608 * otherwise apply backpressure by stopping reads. 1609 */ 1610 if ((r = sshbuf_check_reserve(iqueue, sizeof(buf))) == 0 && 1611 (r = sshbuf_check_reserve(oqueue, 1612 SFTP_MAX_MSG_LENGTH)) == 0) 1613 FD_SET(in, rset); 1614 else if (r != SSH_ERR_NO_BUFFER_SPACE) 1615 fatal("%s: sshbuf_check_reserve failed: %s", 1616 __func__, ssh_err(r)); 1617 1618 olen = sshbuf_len(oqueue); 1619 if (olen > 0) 1620 FD_SET(out, wset); 1621 1622 if (select(max+1, rset, wset, NULL, NULL) < 0) { 1623 if (errno == EINTR) 1624 continue; 1625 error("select: %s", strerror(errno)); 1626 sftp_server_cleanup_exit(2); 1627 } 1628 1629 /* copy stdin to iqueue */ 1630 if (FD_ISSET(in, rset)) { 1631 len = read(in, buf, sizeof buf); 1632 if (len == 0) { 1633 debug("read eof"); 1634 sftp_server_cleanup_exit(0); 1635 } else if (len < 0) { 1636 error("read: %s", strerror(errno)); 1637 sftp_server_cleanup_exit(1); 1638 } else if ((r = sshbuf_put(iqueue, buf, len)) != 0) { 1639 fatal("%s: buffer error: %s", 1640 __func__, ssh_err(r)); 1641 } 1642 } 1643 /* send oqueue to stdout */ 1644 if (FD_ISSET(out, wset)) { 1645 len = write(out, sshbuf_ptr(oqueue), olen); 1646 if (len < 0) { 1647 error("write: %s", strerror(errno)); 1648 sftp_server_cleanup_exit(1); 1649 } else if ((r = sshbuf_consume(oqueue, len)) != 0) { 1650 fatal("%s: buffer error: %s", 1651 __func__, ssh_err(r)); 1652 } 1653 } 1654 1655 /* 1656 * Process requests from client if we can fit the results 1657 * into the output buffer, otherwise stop processing input 1658 * and let the output queue drain. 1659 */ 1660 r = sshbuf_check_reserve(oqueue, SFTP_MAX_MSG_LENGTH); 1661 if (r == 0) 1662 process(); 1663 else if (r != SSH_ERR_NO_BUFFER_SPACE) 1664 fatal("%s: sshbuf_check_reserve: %s", 1665 __func__, ssh_err(r)); 1666 } 1667 } 1668