sftp-client.c

   1 /* $OpenBSD: sftp-client.c,v 1.74 2006/08/03 03:34:42 deraadt Exp $ */
   2 /*
   3  * Copyright (c) 2001-2004 Damien Miller <djm@openbsd.org>
   4  *
   5  * Permission to use, copy, modify, and distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 /* XXX: memleaks */
  19 /* XXX: signed vs unsigned */
  20 /* XXX: remove all logging, only return status codes */
  21 /* XXX: copy between two remote sites */
  22
  23 #include "includes.h"
  24
  25 #include <sys/types.h>
  26 #include <sys/param.h>
  27 #include "openbsd-compat/sys-queue.h"
  28 #ifdef HAVE_SYS_STAT_H
  29 # include <sys/stat.h>
  30 #endif
  31 #ifdef HAVE_SYS_TIME_H
  32 # include <sys/time.h>
  33 #endif
  34 #include <sys/uio.h>
  35
  36 #include <errno.h>
  37 #include <fcntl.h>
  38 #include <signal.h>
  39 #include <stdarg.h>
  40 #include <stdio.h>
  41 #include <string.h>
  42 #include <unistd.h>
  43
  44 #include "xmalloc.h"
  45 #include "buffer.h"
  46 #include "log.h"
  47 #include "atomicio.h"
  48 #include "progressmeter.h"
  49 #include "misc.h"
  50
  51 #include "sftp.h"
  52 #include "sftp-common.h"
  53 #include "sftp-client.h"
  54
  55 extern volatile sig_atomic_t interrupted;
  56 extern int showprogress;
  57
  58 /* Minimum amount of data to read at a time */
  59 #define MIN_READ_SIZE   512
  60
  61 struct sftp_conn {
  62         int fd_in;
  63         int fd_out;
  64         u_int transfer_buflen;
  65         u_int num_requests;
  66         u_int version;
  67         u_int msg_id;
  68 };
  69
  70 static void
  71 send_msg(int fd, Buffer *m)
  72 {
  73         u_char mlen[4];
  74         struct iovec iov[2];
  75
  76         if (buffer_len(m) > SFTP_MAX_MSG_LENGTH)
  77                 fatal("Outbound message too long %u", buffer_len(m));
  78
  79         /* Send length first */
  80         put_u32(mlen, buffer_len(m));
  81         iov[0].iov_base = mlen;
  82         iov[0].iov_len = sizeof(mlen);
  83         iov[1].iov_base = buffer_ptr(m);
  84         iov[1].iov_len = buffer_len(m);
  85
  86         if (atomiciov(writev, fd, iov, 2) != buffer_len(m) + sizeof(mlen))
  87                 fatal("Couldn't send packet: %s", strerror(errno));
  88
  89         buffer_clear(m);
  90 }
  91
  92 static void
  93 get_msg(int fd, Buffer *m)
  94 {
  95         u_int msg_len;
  96
  97         buffer_append_space(m, 4);
  98         if (atomicio(read, fd, buffer_ptr(m), 4) != 4) {
  99                 if (errno == EPIPE)
 100                         fatal("Connection closed");
 101                 else
 102                         fatal("Couldn't read packet: %s", strerror(errno));
 103         }
 104
 105         msg_len = buffer_get_int(m);
 106         if (msg_len > SFTP_MAX_MSG_LENGTH)
 107                 fatal("Received message too long %u", msg_len);
 108
 109         buffer_append_space(m, msg_len);
 110         if (atomicio(read, fd, buffer_ptr(m), msg_len) != msg_len) {
 111                 if (errno == EPIPE)
 112                         fatal("Connection closed");
 113                 else
 114                         fatal("Read packet: %s", strerror(errno));
 115         }
 116 }
 117
 118 static void
 119 send_string_request(int fd, u_int id, u_int code, char *s,
 120     u_int len)
 121 {
 122         Buffer msg;
 123
 124         buffer_init(&msg);
 125         buffer_put_char(&msg, code);
 126         buffer_put_int(&msg, id);
 127         buffer_put_string(&msg, s, len);
 128         send_msg(fd, &msg);
 129         debug3("Sent message fd %d T:%u I:%u", fd, code, id);
 130         buffer_free(&msg);
 131 }
 132
 133 static void
 134 send_string_attrs_request(int fd, u_int id, u_int code, char *s,
 135     u_int len, Attrib *a)
 136 {
 137         Buffer msg;
 138
 139         buffer_init(&msg);
 140         buffer_put_char(&msg, code);
 141         buffer_put_int(&msg, id);
 142         buffer_put_string(&msg, s, len);
 143         encode_attrib(&msg, a);
 144         send_msg(fd, &msg);
 145         debug3("Sent message fd %d T:%u I:%u", fd, code, id);
 146         buffer_free(&msg);
 147 }
 148
 149 static u_int
 150 get_status(int fd, u_int expected_id)
 151 {
 152         Buffer msg;
 153         u_int type, id, status;
 154
 155         buffer_init(&msg);
 156         get_msg(fd, &msg);
 157         type = buffer_get_char(&msg);
 158         id = buffer_get_int(&msg);
 159
 160         if (id != expected_id)
 161                 fatal("ID mismatch (%u != %u)", id, expected_id);
 162         if (type != SSH2_FXP_STATUS)
 163                 fatal("Expected SSH2_FXP_STATUS(%u) packet, got %u",
 164                     SSH2_FXP_STATUS, type);
 165
 166         status = buffer_get_int(&msg);
 167         buffer_free(&msg);
 168
 169         debug3("SSH2_FXP_STATUS %u", status);
 170
 171         return(status);
 172 }
 173
 174 static char *
 175 get_handle(int fd, u_int expected_id, u_int *len)
 176 {
 177         Buffer msg;
 178         u_int type, id;
 179         char *handle;
 180
 181         buffer_init(&msg);
 182         get_msg(fd, &msg);
 183         type = buffer_get_char(&msg);
 184         id = buffer_get_int(&msg);
 185
 186         if (id != expected_id)
 187                 fatal("ID mismatch (%u != %u)", id, expected_id);
 188         if (type == SSH2_FXP_STATUS) {
 189                 int status = buffer_get_int(&msg);
 190
 191                 error("Couldn't get handle: %s", fx2txt(status));
 192                 buffer_free(&msg);
 193                 return(NULL);
 194         } else if (type != SSH2_FXP_HANDLE)
 195                 fatal("Expected SSH2_FXP_HANDLE(%u) packet, got %u",
 196                     SSH2_FXP_HANDLE, type);
 197
 198         handle = buffer_get_string(&msg, len);
 199         buffer_free(&msg);
 200
 201         return(handle);
 202 }
 203
 204 static Attrib *
 205 get_decode_stat(int fd, u_int expected_id, int quiet)
 206 {
 207         Buffer msg;
 208         u_int type, id;
 209         Attrib *a;
 210
 211         buffer_init(&msg);
 212         get_msg(fd, &msg);
 213
 214         type = buffer_get_char(&msg);
 215         id = buffer_get_int(&msg);
 216
 217         debug3("Received stat reply T:%u I:%u", type, id);
 218         if (id != expected_id)
 219                 fatal("ID mismatch (%u != %u)", id, expected_id);
 220         if (type == SSH2_FXP_STATUS) {
 221                 int status = buffer_get_int(&msg);
 222
 223                 if (quiet)
 224                         debug("Couldn't stat remote file: %s", fx2txt(status));
 225                 else
 226                         error("Couldn't stat remote file: %s", fx2txt(status));
 227                 buffer_free(&msg);
 228                 return(NULL);
 229         } else if (type != SSH2_FXP_ATTRS) {
 230                 fatal("Expected SSH2_FXP_ATTRS(%u) packet, got %u",
 231                     SSH2_FXP_ATTRS, type);
 232         }
 233         a = decode_attrib(&msg);
 234         buffer_free(&msg);
 235
 236         return(a);
 237 }
 238
 239 struct sftp_conn *
 240 do_init(int fd_in, int fd_out, u_int transfer_buflen, u_int num_requests)
 241 {
 242         u_int type;
 243         int version;
 244         Buffer msg;
 245         struct sftp_conn *ret;
 246
 247         buffer_init(&msg);
 248         buffer_put_char(&msg, SSH2_FXP_INIT);
 249         buffer_put_int(&msg, SSH2_FILEXFER_VERSION);
 250         send_msg(fd_out, &msg);
 251
 252         buffer_clear(&msg);
 253
 254         get_msg(fd_in, &msg);
 255
 256         /* Expecting a VERSION reply */
 257         if ((type = buffer_get_char(&msg)) != SSH2_FXP_VERSION) {
 258                 error("Invalid packet back from SSH2_FXP_INIT (type %u)",
 259                     type);
 260                 buffer_free(&msg);
 261                 return(NULL);
 262         }
 263         version = buffer_get_int(&msg);
 264
 265         debug2("Remote version: %d", version);
 266
 267         /* Check for extensions */
 268         while (buffer_len(&msg) > 0) {
 269                 char *name = buffer_get_string(&msg, NULL);
 270                 char *value = buffer_get_string(&msg, NULL);
 271
 272                 debug2("Init extension: \"%s\"", name);
 273                 xfree(name);
 274                 xfree(value);
 275         }
 276
 277         buffer_free(&msg);
 278
 279         ret = xmalloc(sizeof(*ret));
 280         ret->fd_in = fd_in;
 281         ret->fd_out = fd_out;
 282         ret->transfer_buflen = transfer_buflen;
 283         ret->num_requests = num_requests;
 284         ret->version = version;
 285         ret->msg_id = 1;
 286
 287         /* Some filexfer v.0 servers don't support large packets */
 288         if (version == 0)
 289                 ret->transfer_buflen = MIN(ret->transfer_buflen, 20480);
 290
 291         return(ret);
 292 }
 293
 294 u_int
 295 sftp_proto_version(struct sftp_conn *conn)
 296 {
 297         return(conn->version);
 298 }
 299
 300 int
 301 do_close(struct sftp_conn *conn, char *handle, u_int handle_len)
 302 {
 303         u_int id, status;
 304         Buffer msg;
 305
 306         buffer_init(&msg);
 307
 308         id = conn->msg_id++;
 309         buffer_put_char(&msg, SSH2_FXP_CLOSE);
 310         buffer_put_int(&msg, id);
 311         buffer_put_string(&msg, handle, handle_len);
 312         send_msg(conn->fd_out, &msg);
 313         debug3("Sent message SSH2_FXP_CLOSE I:%u", id);
 314
 315         status = get_status(conn->fd_in, id);
 316         if (status != SSH2_FX_OK)
 317                 error("Couldn't close file: %s", fx2txt(status));
 318
 319         buffer_free(&msg);
 320
 321         return(status);
 322 }
 323
 324
 325 static int
 326 do_lsreaddir(struct sftp_conn *conn, char *path, int printflag,
 327     SFTP_DIRENT ***dir)
 328 {
 329         Buffer msg;
 330         u_int count, type, id, handle_len, i, expected_id, ents = 0;
 331         char *handle;
 332
 333         id = conn->msg_id++;
 334
 335         buffer_init(&msg);
 336         buffer_put_char(&msg, SSH2_FXP_OPENDIR);
 337         buffer_put_int(&msg, id);
 338         buffer_put_cstring(&msg, path);
 339         send_msg(conn->fd_out, &msg);
 340
 341         buffer_clear(&msg);
 342
 343         handle = get_handle(conn->fd_in, id, &handle_len);
 344         if (handle == NULL)
 345                 return(-1);
 346
 347         if (dir) {
 348                 ents = 0;
 349                 *dir = xmalloc(sizeof(**dir));
 350                 (*dir)[0] = NULL;
 351         }
 352
 353         for (; !interrupted;) {
 354                 id = expected_id = conn->msg_id++;
 355
 356                 debug3("Sending SSH2_FXP_READDIR I:%u", id);
 357
 358                 buffer_clear(&msg);
 359                 buffer_put_char(&msg, SSH2_FXP_READDIR);
 360                 buffer_put_int(&msg, id);
 361                 buffer_put_string(&msg, handle, handle_len);
 362                 send_msg(conn->fd_out, &msg);
 363
 364                 buffer_clear(&msg);
 365
 366                 get_msg(conn->fd_in, &msg);
 367
 368                 type = buffer_get_char(&msg);
 369                 id = buffer_get_int(&msg);
 370
 371                 debug3("Received reply T:%u I:%u", type, id);
 372
 373                 if (id != expected_id)
 374                         fatal("ID mismatch (%u != %u)", id, expected_id);
 375
 376                 if (type == SSH2_FXP_STATUS) {
 377                         int status = buffer_get_int(&msg);
 378
 379                         debug3("Received SSH2_FXP_STATUS %d", status);
 380
 381                         if (status == SSH2_FX_EOF) {
 382                                 break;
 383                         } else {
 384                                 error("Couldn't read directory: %s",
 385                                     fx2txt(status));
 386                                 do_close(conn, handle, handle_len);
 387                                 xfree(handle);
 388                                 return(status);
 389                         }
 390                 } else if (type != SSH2_FXP_NAME)
 391                         fatal("Expected SSH2_FXP_NAME(%u) packet, got %u",
 392                             SSH2_FXP_NAME, type);
 393
 394                 count = buffer_get_int(&msg);
 395                 if (count == 0)
 396                         break;
 397                 debug3("Received %d SSH2_FXP_NAME responses", count);
 398                 for (i = 0; i < count; i++) {
 399                         char *filename, *longname;
 400                         Attrib *a;
 401
 402                         filename = buffer_get_string(&msg, NULL);
 403                         longname = buffer_get_string(&msg, NULL);
 404                         a = decode_attrib(&msg);
 405
 406                         if (printflag)
 407                                 printf("%s\n", longname);
 408
 409                         if (dir) {
 410                                 *dir = xrealloc(*dir, ents + 2, sizeof(**dir));
 411                                 (*dir)[ents] = xmalloc(sizeof(***dir));
 412                                 (*dir)[ents]->filename = xstrdup(filename);
 413                                 (*dir)[ents]->longname = xstrdup(longname);
 414                                 memcpy(&(*dir)[ents]->a, a, sizeof(*a));
 415                                 (*dir)[++ents] = NULL;
 416                         }
 417
 418                         xfree(filename);
 419                         xfree(longname);
 420                 }
 421         }
 422
 423         buffer_free(&msg);
 424         do_close(conn, handle, handle_len);
 425         xfree(handle);
 426
 427         /* Don't return partial matches on interrupt */
 428         if (interrupted && dir != NULL && *dir != NULL) {
 429                 free_sftp_dirents(*dir);
 430                 *dir = xmalloc(sizeof(**dir));
 431                 **dir = NULL;
 432         }
 433
 434         return(0);
 435 }
 436
 437 int
 438 do_readdir(struct sftp_conn *conn, char *path, SFTP_DIRENT ***dir)
 439 {
 440         return(do_lsreaddir(conn, path, 0, dir));
 441 }
 442
 443 void free_sftp_dirents(SFTP_DIRENT **s)
 444 {
 445         int i;
 446
 447         for (i = 0; s[i]; i++) {
 448                 xfree(s[i]->filename);
 449                 xfree(s[i]->longname);
 450                 xfree(s[i]);
 451         }
 452         xfree(s);
 453 }
 454
 455 int
 456 do_rm(struct sftp_conn *conn, char *path)
 457 {
 458         u_int status, id;
 459
 460         debug2("Sending SSH2_FXP_REMOVE \"%s\"", path);
 461
 462         id = conn->msg_id++;
 463         send_string_request(conn->fd_out, id, SSH2_FXP_REMOVE, path,
 464             strlen(path));
 465         status = get_status(conn->fd_in, id);
 466         if (status != SSH2_FX_OK)
 467                 error("Couldn't delete file: %s", fx2txt(status));
 468         return(status);
 469 }
 470
 471 int
 472 do_mkdir(struct sftp_conn *conn, char *path, Attrib *a)
 473 {
 474         u_int status, id;
 475
 476         id = conn->msg_id++;
 477         send_string_attrs_request(conn->fd_out, id, SSH2_FXP_MKDIR, path,
 478             strlen(path), a);
 479
 480         status = get_status(conn->fd_in, id);
 481         if (status != SSH2_FX_OK)
 482                 error("Couldn't create directory: %s", fx2txt(status));
 483
 484         return(status);
 485 }
 486
 487 int
 488 do_rmdir(struct sftp_conn *conn, char *path)
 489 {
 490         u_int status, id;
 491
 492         id = conn->msg_id++;
 493         send_string_request(conn->fd_out, id, SSH2_FXP_RMDIR, path,
 494             strlen(path));
 495
 496         status = get_status(conn->fd_in, id);
 497         if (status != SSH2_FX_OK)
 498                 error("Couldn't remove directory: %s", fx2txt(status));
 499
 500         return(status);
 501 }
 502
 503 Attrib *
 504 do_stat(struct sftp_conn *conn, char *path, int quiet)
 505 {
 506         u_int id;
 507
 508         id = conn->msg_id++;
 509
 510         send_string_request(conn->fd_out, id,
 511             conn->version == 0 ? SSH2_FXP_STAT_VERSION_0 : SSH2_FXP_STAT,
 512             path, strlen(path));
 513
 514         return(get_decode_stat(conn->fd_in, id, quiet));
 515 }
 516
 517 Attrib *
 518 do_lstat(struct sftp_conn *conn, char *path, int quiet)
 519 {
 520         u_int id;
 521
 522         if (conn->version == 0) {
 523                 if (quiet)
 524                         debug("Server version does not support lstat operation");
 525                 else
 526                         logit("Server version does not support lstat operation");
 527                 return(do_stat(conn, path, quiet));
 528         }
 529
 530         id = conn->msg_id++;
 531         send_string_request(conn->fd_out, id, SSH2_FXP_LSTAT, path,
 532             strlen(path));
 533
 534         return(get_decode_stat(conn->fd_in, id, quiet));
 535 }
 536
 537 Attrib *
 538 do_fstat(struct sftp_conn *conn, char *handle, u_int handle_len, int quiet)
 539 {
 540         u_int id;
 541
 542         id = conn->msg_id++;
 543         send_string_request(conn->fd_out, id, SSH2_FXP_FSTAT, handle,
 544             handle_len);
 545
 546         return(get_decode_stat(conn->fd_in, id, quiet));
 547 }
 548
 549 int
 550 do_setstat(struct sftp_conn *conn, char *path, Attrib *a)
 551 {
 552         u_int status, id;
 553
 554         id = conn->msg_id++;
 555         send_string_attrs_request(conn->fd_out, id, SSH2_FXP_SETSTAT, path,
 556             strlen(path), a);
 557
 558         status = get_status(conn->fd_in, id);
 559         if (status != SSH2_FX_OK)
 560                 error("Couldn't setstat on \"%s\": %s", path,
 561                     fx2txt(status));
 562
 563         return(status);
 564 }
 565
 566 int
 567 do_fsetstat(struct sftp_conn *conn, char *handle, u_int handle_len,
 568     Attrib *a)
 569 {
 570         u_int status, id;
 571
 572         id = conn->msg_id++;
 573         send_string_attrs_request(conn->fd_out, id, SSH2_FXP_FSETSTAT, handle,
 574             handle_len, a);
 575
 576         status = get_status(conn->fd_in, id);
 577         if (status != SSH2_FX_OK)
 578                 error("Couldn't fsetstat: %s", fx2txt(status));
 579
 580         return(status);
 581 }
 582
 583 char *
 584 do_realpath(struct sftp_conn *conn, char *path)
 585 {
 586         Buffer msg;
 587         u_int type, expected_id, count, id;
 588         char *filename, *longname;
 589         Attrib *a;
 590
 591         expected_id = id = conn->msg_id++;
 592         send_string_request(conn->fd_out, id, SSH2_FXP_REALPATH, path,
 593             strlen(path));
 594
 595         buffer_init(&msg);
 596
 597         get_msg(conn->fd_in, &msg);
 598         type = buffer_get_char(&msg);
 599         id = buffer_get_int(&msg);
 600
 601         if (id != expected_id)
 602                 fatal("ID mismatch (%u != %u)", id, expected_id);
 603
 604         if (type == SSH2_FXP_STATUS) {
 605                 u_int status = buffer_get_int(&msg);
 606
 607                 error("Couldn't canonicalise: %s", fx2txt(status));
 608                 return(NULL);
 609         } else if (type != SSH2_FXP_NAME)
 610                 fatal("Expected SSH2_FXP_NAME(%u) packet, got %u",
 611                     SSH2_FXP_NAME, type);
 612
 613         count = buffer_get_int(&msg);
 614         if (count != 1)
 615                 fatal("Got multiple names (%d) from SSH_FXP_REALPATH", count);
 616
 617         filename = buffer_get_string(&msg, NULL);
 618         longname = buffer_get_string(&msg, NULL);
 619         a = decode_attrib(&msg);
 620
 621         debug3("SSH_FXP_REALPATH %s -> %s", path, filename);
 622
 623         xfree(longname);
 624
 625         buffer_free(&msg);
 626
 627         return(filename);
 628 }
 629
 630 int
 631 do_rename(struct sftp_conn *conn, char *oldpath, char *newpath)
 632 {
 633         Buffer msg;
 634         u_int status, id;
 635
 636         buffer_init(&msg);
 637
 638         /* Send rename request */
 639         id = conn->msg_id++;
 640         buffer_put_char(&msg, SSH2_FXP_RENAME);
 641         buffer_put_int(&msg, id);
 642         buffer_put_cstring(&msg, oldpath);
 643         buffer_put_cstring(&msg, newpath);
 644         send_msg(conn->fd_out, &msg);
 645         debug3("Sent message SSH2_FXP_RENAME \"%s\" -> \"%s\"", oldpath,
 646             newpath);
 647         buffer_free(&msg);
 648
 649         status = get_status(conn->fd_in, id);
 650         if (status != SSH2_FX_OK)
 651                 error("Couldn't rename file \"%s\" to \"%s\": %s", oldpath,
 652                     newpath, fx2txt(status));
 653
 654         return(status);
 655 }
 656
 657 int
 658 do_symlink(struct sftp_conn *conn, char *oldpath, char *newpath)
 659 {
 660         Buffer msg;
 661         u_int status, id;
 662
 663         if (conn->version < 3) {
 664                 error("This server does not support the symlink operation");
 665                 return(SSH2_FX_OP_UNSUPPORTED);
 666         }
 667
 668         buffer_init(&msg);
 669
 670         /* Send symlink request */
 671         id = conn->msg_id++;
 672         buffer_put_char(&msg, SSH2_FXP_SYMLINK);
 673         buffer_put_int(&msg, id);
 674         buffer_put_cstring(&msg, oldpath);
 675         buffer_put_cstring(&msg, newpath);
 676         send_msg(conn->fd_out, &msg);
 677         debug3("Sent message SSH2_FXP_SYMLINK \"%s\" -> \"%s\"", oldpath,
 678             newpath);
 679         buffer_free(&msg);
 680
 681         status = get_status(conn->fd_in, id);
 682         if (status != SSH2_FX_OK)
 683                 error("Couldn't symlink file \"%s\" to \"%s\": %s", oldpath,
 684                     newpath, fx2txt(status));
 685
 686         return(status);
 687 }
 688
 689 char *
 690 do_readlink(struct sftp_conn *conn, char *path)
 691 {
 692         Buffer msg;
 693         u_int type, expected_id, count, id;
 694         char *filename, *longname;
 695         Attrib *a;
 696
 697         expected_id = id = conn->msg_id++;
 698         send_string_request(conn->fd_out, id, SSH2_FXP_READLINK, path,
 699             strlen(path));
 700
 701         buffer_init(&msg);
 702
 703         get_msg(conn->fd_in, &msg);
 704         type = buffer_get_char(&msg);
 705         id = buffer_get_int(&msg);
 706
 707         if (id != expected_id)
 708                 fatal("ID mismatch (%u != %u)", id, expected_id);
 709
 710         if (type == SSH2_FXP_STATUS) {
 711                 u_int status = buffer_get_int(&msg);
 712
 713                 error("Couldn't readlink: %s", fx2txt(status));
 714                 return(NULL);
 715         } else if (type != SSH2_FXP_NAME)
 716                 fatal("Expected SSH2_FXP_NAME(%u) packet, got %u",
 717                     SSH2_FXP_NAME, type);
 718
 719         count = buffer_get_int(&msg);
 720         if (count != 1)
 721                 fatal("Got multiple names (%d) from SSH_FXP_READLINK", count);
 722
 723         filename = buffer_get_string(&msg, NULL);
 724         longname = buffer_get_string(&msg, NULL);
 725         a = decode_attrib(&msg);
 726
 727         debug3("SSH_FXP_READLINK %s -> %s", path, filename);
 728
 729         xfree(longname);
 730
 731         buffer_free(&msg);
 732
 733         return(filename);
 734 }
 735
 736 static void
 737 send_read_request(int fd_out, u_int id, u_int64_t offset, u_int len,
 738     char *handle, u_int handle_len)
 739 {
 740         Buffer msg;
 741
 742         buffer_init(&msg);
 743         buffer_clear(&msg);
 744         buffer_put_char(&msg, SSH2_FXP_READ);
 745         buffer_put_int(&msg, id);
 746         buffer_put_string(&msg, handle, handle_len);
 747         buffer_put_int64(&msg, offset);
 748         buffer_put_int(&msg, len);
 749         send_msg(fd_out, &msg);
 750         buffer_free(&msg);
 751 }
 752
 753 int
 754 do_download(struct sftp_conn *conn, char *remote_path, char *local_path,
 755     int pflag)
 756 {
 757         Attrib junk, *a;
 758         Buffer msg;
 759         char *handle;
 760         int local_fd, status = 0, write_error;
 761         int read_error, write_errno;
 762         u_int64_t offset, size;
 763         u_int handle_len, mode, type, id, buflen, num_req, max_req;
 764         off_t progress_counter;
 765         struct request {
 766                 u_int id;
 767                 u_int len;
 768                 u_int64_t offset;
 769                 TAILQ_ENTRY(request) tq;
 770         };
 771         TAILQ_HEAD(reqhead, request) requests;
 772         struct request *req;
 773
 774         TAILQ_INIT(&requests);
 775
 776         a = do_stat(conn, remote_path, 0);
 777         if (a == NULL)
 778                 return(-1);
 779
 780         /* XXX: should we preserve set[ug]id? */
 781         if (a->flags & SSH2_FILEXFER_ATTR_PERMISSIONS)
 782                 mode = a->perm & 0777;
 783         else
 784                 mode = 0666;
 785
 786         if ((a->flags & SSH2_FILEXFER_ATTR_PERMISSIONS) &&
 787             (!S_ISREG(a->perm))) {
 788                 error("Cannot download non-regular file: %s", remote_path);
 789                 return(-1);
 790         }
 791
 792         if (a->flags & SSH2_FILEXFER_ATTR_SIZE)
 793                 size = a->size;
 794         else
 795                 size = 0;
 796
 797         buflen = conn->transfer_buflen;
 798         buffer_init(&msg);
 799
 800         /* Send open request */
 801         id = conn->msg_id++;
 802         buffer_put_char(&msg, SSH2_FXP_OPEN);
 803         buffer_put_int(&msg, id);
 804         buffer_put_cstring(&msg, remote_path);
 805         buffer_put_int(&msg, SSH2_FXF_READ);
 806         attrib_clear(&junk); /* Send empty attributes */
 807         encode_attrib(&msg, &junk);
 808         send_msg(conn->fd_out, &msg);
 809         debug3("Sent message SSH2_FXP_OPEN I:%u P:%s", id, remote_path);
 810
 811         handle = get_handle(conn->fd_in, id, &handle_len);
 812         if (handle == NULL) {
 813                 buffer_free(&msg);
 814                 return(-1);
 815         }
 816
 817         local_fd = open(local_path, O_WRONLY | O_CREAT | O_TRUNC,
 818             mode | S_IWRITE);
 819         if (local_fd == -1) {
 820                 error("Couldn't open local file \"%s\" for writing: %s",
 821                     local_path, strerror(errno));
 822                 buffer_free(&msg);
 823                 xfree(handle);
 824                 return(-1);
 825         }
 826
 827         /* Read from remote and write to local */
 828         write_error = read_error = write_errno = num_req = offset = 0;
 829         max_req = 1;
 830         progress_counter = 0;
 831
 832         if (showprogress && size != 0)
 833                 start_progress_meter(remote_path, size, &progress_counter);
 834
 835         while (num_req > 0 || max_req > 0) {
 836                 char *data;
 837                 u_int len;
 838
 839                 /*
 840                  * Simulate EOF on interrupt: stop sending new requests and
 841                  * allow outstanding requests to drain gracefully
 842                  */
 843                 if (interrupted) {
 844                         if (num_req == 0) /* If we haven't started yet... */
 845                                 break;
 846                         max_req = 0;
 847                 }
 848
 849                 /* Send some more requests */
 850                 while (num_req < max_req) {
 851                         debug3("Request range %llu -> %llu (%d/%d)",
 852                             (unsigned long long)offset,
 853                             (unsigned long long)offset + buflen - 1,
 854                             num_req, max_req);
 855                         req = xmalloc(sizeof(*req));
 856                         req->id = conn->msg_id++;
 857                         req->len = buflen;
 858                         req->offset = offset;
 859                         offset += buflen;
 860                         num_req++;
 861                         TAILQ_INSERT_TAIL(&requests, req, tq);
 862                         send_read_request(conn->fd_out, req->id, req->offset,
 863                             req->len, handle, handle_len);
 864                 }
 865
 866                 buffer_clear(&msg);
 867                 get_msg(conn->fd_in, &msg);
 868                 type = buffer_get_char(&msg);
 869                 id = buffer_get_int(&msg);
 870                 debug3("Received reply T:%u I:%u R:%d", type, id, max_req);
 871
 872                 /* Find the request in our queue */
 873                 for (req = TAILQ_FIRST(&requests);
 874                     req != NULL && req->id != id;
 875                     req = TAILQ_NEXT(req, tq))
 876                         ;
 877                 if (req == NULL)
 878                         fatal("Unexpected reply %u", id);
 879
 880                 switch (type) {
 881                 case SSH2_FXP_STATUS:
 882                         status = buffer_get_int(&msg);
 883                         if (status != SSH2_FX_EOF)
 884                                 read_error = 1;
 885                         max_req = 0;
 886                         TAILQ_REMOVE(&requests, req, tq);
 887                         xfree(req);
 888                         num_req--;
 889                         break;
 890                 case SSH2_FXP_DATA:
 891                         data = buffer_get_string(&msg, &len);
 892                         debug3("Received data %llu -> %llu",
 893                             (unsigned long long)req->offset,
 894                             (unsigned long long)req->offset + len - 1);
 895                         if (len > req->len)
 896                                 fatal("Received more data than asked for "
 897                                     "%u > %u", len, req->len);
 898                         if ((lseek(local_fd, req->offset, SEEK_SET) == -1 ||
 899                             atomicio(vwrite, local_fd, data, len) != len) &&
 900                             !write_error) {
 901                                 write_errno = errno;
 902                                 write_error = 1;
 903                                 max_req = 0;
 904                         }
 905                         progress_counter += len;
 906                         xfree(data);
 907
 908                         if (len == req->len) {
 909                                 TAILQ_REMOVE(&requests, req, tq);
 910                                 xfree(req);
 911                                 num_req--;
 912                         } else {
 913                                 /* Resend the request for the missing data */
 914                                 debug3("Short data block, re-requesting "
 915                                     "%llu -> %llu (%2d)",
 916                                     (unsigned long long)req->offset + len,
 917                                     (unsigned long long)req->offset +
 918                                     req->len - 1, num_req);
 919                                 req->id = conn->msg_id++;
 920                                 req->len -= len;
 921                                 req->offset += len;
 922                                 send_read_request(conn->fd_out, req->id,
 923                                     req->offset, req->len, handle, handle_len);
 924                                 /* Reduce the request size */
 925                                 if (len < buflen)
 926                                         buflen = MAX(MIN_READ_SIZE, len);
 927                         }
 928                         if (max_req > 0) { /* max_req = 0 iff EOF received */
 929                                 if (size > 0 && offset > size) {
 930                                         /* Only one request at a time
 931                                          * after the expected EOF */
 932                                         debug3("Finish at %llu (%2d)",
 933                                             (unsigned long long)offset,
 934                                             num_req);
 935                                         max_req = 1;
 936                                 } else if (max_req <= conn->num_requests) {
 937                                         ++max_req;
 938                                 }
 939                         }
 940                         break;
 941                 default:
 942                         fatal("Expected SSH2_FXP_DATA(%u) packet, got %u",
 943                             SSH2_FXP_DATA, type);
 944                 }
 945         }
 946
 947         if (showprogress && size)
 948                 stop_progress_meter();
 949
 950         /* Sanity check */
 951         if (TAILQ_FIRST(&requests) != NULL)
 952                 fatal("Transfer complete, but requests still in queue");
 953
 954         if (read_error) {
 955                 error("Couldn't read from remote file \"%s\" : %s",
 956                     remote_path, fx2txt(status));
 957                 do_close(conn, handle, handle_len);
 958         } else if (write_error) {
 959                 error("Couldn't write to \"%s\": %s", local_path,
 960                     strerror(write_errno));
 961                 status = -1;
 962                 do_close(conn, handle, handle_len);
 963         } else {
 964                 status = do_close(conn, handle, handle_len);
 965
 966                 /* Override umask and utimes if asked */
 967 #ifdef HAVE_FCHMOD
 968                 if (pflag && fchmod(local_fd, mode) == -1)
 969 #else
 970                 if (pflag && chmod(local_path, mode) == -1)
 971 #endif /* HAVE_FCHMOD */
 972                         error("Couldn't set mode on \"%s\": %s", local_path,
 973                             strerror(errno));
 974                 if (pflag && (a->flags & SSH2_FILEXFER_ATTR_ACMODTIME)) {
 975                         struct timeval tv[2];
 976                         tv[0].tv_sec = a->atime;
 977                         tv[1].tv_sec = a->mtime;
 978                         tv[0].tv_usec = tv[1].tv_usec = 0;
 979                         if (utimes(local_path, tv) == -1)
 980                                 error("Can't set times on \"%s\": %s",
 981                                     local_path, strerror(errno));
 982                 }
 983         }
 984         close(local_fd);
 985         buffer_free(&msg);
 986         xfree(handle);
 987
 988         return(status);
 989 }
 990
 991 int
 992 do_upload(struct sftp_conn *conn, char *local_path, char *remote_path,
 993     int pflag)
 994 {
 995         int local_fd, status;
 996         u_int handle_len, id, type;
 997         u_int64_t offset;
 998         char *handle, *data;
 999         Buffer msg;
1000         struct stat sb;
1001         Attrib a;
1002         u_int32_t startid;
1003         u_int32_t ackid;
1004         struct outstanding_ack {
1005                 u_int id;
1006                 u_int len;
1007                 u_int64_t offset;
1008                 TAILQ_ENTRY(outstanding_ack) tq;
1009         };
1010         TAILQ_HEAD(ackhead, outstanding_ack) acks;
1011         struct outstanding_ack *ack = NULL;
1012
1013         TAILQ_INIT(&acks);
1014
1015         if ((local_fd = open(local_path, O_RDONLY, 0)) == -1) {
1016                 error("Couldn't open local file \"%s\" for reading: %s",
1017                     local_path, strerror(errno));
1018                 return(-1);
1019         }
1020         if (fstat(local_fd, &sb) == -1) {
1021                 error("Couldn't fstat local file \"%s\": %s",
1022                     local_path, strerror(errno));
1023                 close(local_fd);
1024                 return(-1);
1025         }
1026         if (!S_ISREG(sb.st_mode)) {
1027                 error("%s is not a regular file", local_path);
1028                 close(local_fd);
1029                 return(-1);
1030         }
1031         stat_to_attrib(&sb, &a);
1032
1033         a.flags &= ~SSH2_FILEXFER_ATTR_SIZE;
1034         a.flags &= ~SSH2_FILEXFER_ATTR_UIDGID;
1035         a.perm &= 0777;
1036         if (!pflag)
1037                 a.flags &= ~SSH2_FILEXFER_ATTR_ACMODTIME;
1038
1039         buffer_init(&msg);
1040
1041         /* Send open request */
1042         id = conn->msg_id++;
1043         buffer_put_char(&msg, SSH2_FXP_OPEN);
1044         buffer_put_int(&msg, id);
1045         buffer_put_cstring(&msg, remote_path);
1046         buffer_put_int(&msg, SSH2_FXF_WRITE|SSH2_FXF_CREAT|SSH2_FXF_TRUNC);
1047         encode_attrib(&msg, &a);
1048         send_msg(conn->fd_out, &msg);
1049         debug3("Sent message SSH2_FXP_OPEN I:%u P:%s", id, remote_path);
1050
1051         buffer_clear(&msg);
1052
1053         handle = get_handle(conn->fd_in, id, &handle_len);
1054         if (handle == NULL) {
1055                 close(local_fd);
1056                 buffer_free(&msg);
1057                 return(-1);
1058         }
1059
1060         startid = ackid = id + 1;
1061         data = xmalloc(conn->transfer_buflen);
1062
1063         /* Read from local and write to remote */
1064         offset = 0;
1065         if (showprogress)
1066                 start_progress_meter(local_path, sb.st_size, &offset);
1067
1068         for (;;) {
1069                 int len;
1070
1071                 /*
1072                  * Can't use atomicio here because it returns 0 on EOF,
1073                  * thus losing the last block of the file.
1074                  * Simulate an EOF on interrupt, allowing ACKs from the
1075                  * server to drain.
1076                  */
1077                 if (interrupted)
1078                         len = 0;
1079                 else do
1080                         len = read(local_fd, data, conn->transfer_buflen);
1081                 while ((len == -1) && (errno == EINTR || errno == EAGAIN));
1082
1083                 if (len == -1)
1084                         fatal("Couldn't read from \"%s\": %s", local_path,
1085                             strerror(errno));
1086
1087                 if (len != 0) {
1088                         ack = xmalloc(sizeof(*ack));
1089                         ack->id = ++id;
1090                         ack->offset = offset;
1091                         ack->len = len;
1092                         TAILQ_INSERT_TAIL(&acks, ack, tq);
1093
1094                         buffer_clear(&msg);
1095                         buffer_put_char(&msg, SSH2_FXP_WRITE);
1096                         buffer_put_int(&msg, ack->id);
1097                         buffer_put_string(&msg, handle, handle_len);
1098                         buffer_put_int64(&msg, offset);
1099                         buffer_put_string(&msg, data, len);
1100                         send_msg(conn->fd_out, &msg);
1101                         debug3("Sent message SSH2_FXP_WRITE I:%u O:%llu S:%u",
1102                             id, (unsigned long long)offset, len);
1103                 } else if (TAILQ_FIRST(&acks) == NULL)
1104                         break;
1105
1106                 if (ack == NULL)
1107                         fatal("Unexpected ACK %u", id);
1108
1109                 if (id == startid || len == 0 ||
1110                     id - ackid >= conn->num_requests) {
1111                         u_int r_id;
1112
1113                         buffer_clear(&msg);
1114                         get_msg(conn->fd_in, &msg);
1115                         type = buffer_get_char(&msg);
1116                         r_id = buffer_get_int(&msg);
1117
1118                         if (type != SSH2_FXP_STATUS)
1119                                 fatal("Expected SSH2_FXP_STATUS(%d) packet, "
1120                                     "got %d", SSH2_FXP_STATUS, type);
1121
1122                         status = buffer_get_int(&msg);
1123                         debug3("SSH2_FXP_STATUS %d", status);
1124
1125                         /* Find the request in our queue */
1126                         for (ack = TAILQ_FIRST(&acks);
1127                             ack != NULL && ack->id != r_id;
1128                             ack = TAILQ_NEXT(ack, tq))
1129                                 ;
1130                         if (ack == NULL)
1131                                 fatal("Can't find request for ID %u", r_id);
1132                         TAILQ_REMOVE(&acks, ack, tq);
1133
1134                         if (status != SSH2_FX_OK) {
1135                                 error("Couldn't write to remote file \"%s\": %s",
1136                                     remote_path, fx2txt(status));
1137                                 do_close(conn, handle, handle_len);
1138                                 close(local_fd);
1139                                 xfree(data);
1140                                 xfree(ack);
1141                                 goto done;
1142                         }
1143                         debug3("In write loop, ack for %u %u bytes at %llu",
1144                             ack->id, ack->len, (unsigned long long)ack->offset);
1145                         ++ackid;
1146                         xfree(ack);
1147                 }
1148                 offset += len;
1149         }
1150         if (showprogress)
1151                 stop_progress_meter();
1152         xfree(data);
1153
1154         if (close(local_fd) == -1) {
1155                 error("Couldn't close local file \"%s\": %s", local_path,
1156                     strerror(errno));
1157                 do_close(conn, handle, handle_len);
1158                 status = -1;
1159                 goto done;
1160         }
1161
1162         /* Override umask and utimes if asked */
1163         if (pflag)
1164                 do_fsetstat(conn, handle, handle_len, &a);
1165
1166         status = do_close(conn, handle, handle_len);
1167
1168 done:
1169         xfree(handle);
1170         buffer_free(&msg);
1171         return(status);
1172 }