1/* $OpenBSD: ftpd.c,v 1.234 2024/05/09 08:35:03 florian Exp $ */ 2/* $NetBSD: ftpd.c,v 1.15 1995/06/03 22:46:47 mycroft Exp $ */ 3 4/* 5 * Copyright (C) 1997 and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33/* 34 * Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. Neither the name of the University nor the names of its contributors 46 * may be used to endorse or promote products derived from this software 47 * without specific prior written permission. 48 * 49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 59 * SUCH DAMAGE. 60 */ 61 62/* 63 * FTP server. 64 */ 65#include <sys/stat.h> 66#include <sys/ioctl.h> 67#include <sys/socket.h> 68#include <sys/wait.h> 69#include <sys/mman.h> 70 71#include <netinet/in.h> 72#include <netinet/ip.h> 73#include <netinet/tcp.h> 74 75#define FTP_NAMES 76#include <arpa/ftp.h> 77#include <arpa/inet.h> 78#include <arpa/telnet.h> 79 80#include <bsd_auth.h> 81#include <ctype.h> 82#include <dirent.h> 83#include <errno.h> 84#include <fcntl.h> 85#include <glob.h> 86#include <limits.h> 87#include <login_cap.h> 88#include <netdb.h> 89#include <pwd.h> 90#include <signal.h> 91#include <stdarg.h> 92#include <stdio.h> 93#include <stdlib.h> 94#include <string.h> 95#include <syslog.h> 96#include <time.h> 97#include <vis.h> 98#include <unistd.h> 99#include <utmp.h> 100#include <poll.h> 101 102#include "pathnames.h" 103#include "monitor.h" 104#include "extern.h" 105 106extern off_t restart_point; 107extern char cbuf[]; 108 109union sockunion ctrl_addr; 110union sockunion data_source; 111union sockunion data_dest; 112union sockunion his_addr; 113union sockunion pasv_addr; 114 115sigset_t allsigs; 116 117int daemon_mode = 0; 118int data; 119int logged_in; 120struct passwd *pw; 121int debug = 0; 122int timeout = 900; /* timeout after 15 minutes of inactivity */ 123int maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */ 124int logging; 125int anon_ok = 1; 126int anon_only = 0; 127unsigned int minuid = 1000; 128int multihome = 0; 129int guest; 130int stats; 131int statfd = -1; 132int portcheck = 1; 133int dochroot; 134int type; 135int form; 136int stru; /* avoid C keyword */ 137int mode; 138int doutmp = 0; /* update utmp file */ 139int nowtmp = 0; /* do not update wtmp file */ 140int usedefault = 1; /* for data transfers */ 141int pdata = -1; /* for passive mode */ 142int family = AF_UNSPEC; 143volatile sig_atomic_t transflag; 144off_t file_size; 145off_t byte_count; 146mode_t defumask = S_IWGRP|S_IWOTH; /* default umask value */ 147int umaskchange = 1; /* allow user to change umask value. */ 148char tmpline[7]; 149char hostname[HOST_NAME_MAX+1]; 150char remotehost[HOST_NAME_MAX+1]; 151char dhostname[HOST_NAME_MAX+1]; 152char *guestpw; 153char ttyline[20]; 154static struct utmp utmp; /* for utmp */ 155static login_cap_t *lc; 156static auth_session_t *as; 157static volatile sig_atomic_t recvurg; 158 159int epsvall = 0; 160 161/* 162 * Timeout intervals for retrying connections 163 * to hosts that don't accept PORT cmds. This 164 * is a kludge, but given the problems with TCP... 165 */ 166#define SWAITMAX 90 /* wait at most 90 seconds */ 167#define SWAITINT 5 /* interval between retries */ 168 169int swaitmax = SWAITMAX; 170int swaitint = SWAITINT; 171 172char proctitle[BUFSIZ]; /* initial part of title */ 173 174#define LOGCMD(cmd, file) \ 175 if (logging > 1) \ 176 syslog(LOG_INFO,"%s %s%s", cmd, \ 177 *(file) == '/' ? "" : curdir(), file); 178#define LOGCMD2(cmd, file1, file2) \ 179 if (logging > 1) \ 180 syslog(LOG_INFO,"%s %s%s %s%s", cmd, \ 181 *(file1) == '/' ? "" : curdir(), file1, \ 182 *(file2) == '/' ? "" : curdir(), file2); 183#define LOGBYTES(cmd, file, cnt) \ 184 if (logging > 1) { \ 185 if ((cnt) == -1) \ 186 syslog(LOG_INFO,"%s %s%s", cmd, \ 187 *(file) == '/' ? "" : curdir(), file); \ 188 else \ 189 syslog(LOG_INFO, "%s %s%s = %lld bytes", \ 190 cmd, (*(file) == '/') ? "" : curdir(), file, \ 191 (long long)(cnt)); \ 192 } 193 194static void ack(const char *); 195static void sigurg(int); 196static void myoob(void); 197static int checkuser(char *, const char *); 198static FILE *dataconn(const char *, off_t, char *); 199static void dolog(struct sockaddr *); 200static char *copy_dir(char *, struct passwd *); 201static char *curdir(void); 202static void end_login(void); 203static FILE *getdatasock(char *); 204static int guniquefd(const char *, char **); 205static void lostconn(int); 206static void sigquit(int); 207static int receive_data(FILE *, FILE *); 208static void replydirname(const char *, const char *); 209static int send_data(FILE *, FILE *, off_t, off_t, int); 210static struct passwd * 211 sgetpwnam(const char *, struct passwd *); 212static void reapchild(int); 213static void usage(void); 214 215void logxfer(const char *, off_t, time_t); 216void set_slave_signals(void); 217 218static char * 219curdir(void) 220{ 221 static char path[PATH_MAX+1]; /* path + '/' */ 222 223 if (getcwd(path, sizeof(path)-1) == NULL) 224 return (""); 225 if (path[1] != '\0') /* special case for root dir. */ 226 strlcat(path, "/", sizeof path); 227 /* For guest account, skip / since it's chrooted */ 228 return (guest ? path+1 : path); 229} 230 231char *argstr = "AdDhnlm:MSt:T:u:PUvW46"; 232 233static void 234usage(void) 235{ 236 syslog(LOG_ERR, 237 "usage: ftpd [-46ADdlMnPSUW] [-m minuid] [-T maxtimeout] " 238 "[-t timeout] [-u mask]"); 239 exit(2); 240} 241 242int 243main(int argc, char *argv[]) 244{ 245 socklen_t addrlen; 246 int ch, on = 1, tos; 247 char line[LINE_MAX]; 248 FILE *fp; 249 struct hostent *hp; 250 struct sigaction sa; 251 int error = 0; 252 const char *errstr; 253 254 tzset(); /* in case no timezone database in ~ftp */ 255 sigfillset(&allsigs); /* used to block signals while root */ 256 sigemptyset(&sa.sa_mask); 257 sa.sa_flags = SA_RESTART; 258 259 while ((ch = getopt(argc, argv, argstr)) != -1) { 260 switch (ch) { 261 case 'A': 262 anon_only = 1; 263 break; 264 265 case 'd': 266 case 'v': /* deprecated */ 267 debug = 1; 268 break; 269 270 case 'D': 271 daemon_mode = 1; 272 break; 273 274 case 'P': 275 portcheck = 0; 276 break; 277 278 case 'h': /* deprecated */ 279 break; 280 281 case 'l': 282 logging++; /* > 1 == extra logging */ 283 break; 284 285 case 'm': 286 minuid = strtonum(optarg, 0, UINT_MAX, &errstr); 287 if (errstr) { 288 syslog(LOG_ERR, 289 "%s is a bad value for -m, aborting", 290 optarg); 291 exit(2); 292 } 293 break; 294 295 case 'M': 296 multihome = 1; 297 break; 298 299 case 'n': 300 anon_ok = 0; 301 break; 302 303 case 'S': 304 stats = 1; 305 break; 306 307 case 't': 308 timeout = strtonum(optarg, 0, INT_MAX, &errstr); 309 if (errstr) { 310 syslog(LOG_ERR, 311 "%s is a bad value for -t, aborting", 312 optarg); 313 exit(2); 314 } 315 if (maxtimeout < timeout) 316 maxtimeout = timeout; 317 break; 318 319 case 'T': 320 maxtimeout = strtonum(optarg, 0, INT_MAX, 321 &errstr); 322 if (errstr) { 323 syslog(LOG_ERR, 324 "%s is a bad value for -T, aborting", 325 optarg); 326 exit(2); 327 } 328 if (timeout > maxtimeout) 329 timeout = maxtimeout; 330 break; 331 332 case 'u': 333 { 334 long val = 0; 335 char *p; 336 umaskchange = 0; 337 338 val = strtol(optarg, &p, 8); 339 if (*optarg == '\0' || *p != '\0' || val < 0 || 340 (val & ~ACCESSPERMS)) { 341 syslog(LOG_ERR, 342 "%s is a bad value for -u, aborting", 343 optarg); 344 exit(2); 345 } 346 defumask = val; 347 break; 348 } 349 350 case 'U': 351 doutmp = 1; 352 break; 353 354 case 'W': 355 nowtmp = 1; 356 break; 357 358 case '4': 359 family = AF_INET; 360 break; 361 362 case '6': 363 family = AF_INET6; 364 break; 365 366 default: 367 usage(); 368 break; 369 } 370 } 371 372 if (nowtmp && doutmp) { 373 syslog(LOG_ERR, "options 'U' and 'W' are mutually exclusive"); 374 exit(1); 375 } 376 377 (void) freopen(_PATH_DEVNULL, "w", stderr); 378 379 /* 380 * LOG_NDELAY sets up the logging connection immediately, 381 * necessary for anonymous ftp's that chroot and can't do it later. 382 */ 383 openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP); 384 385 if (getpwnam(FTPD_PRIVSEP_USER) == NULL) { 386 syslog(LOG_ERR, "privilege separation user %s not found", 387 FTPD_PRIVSEP_USER); 388 exit(1); 389 } 390 endpwent(); 391 392 if (daemon_mode) { 393 int *fds, fd; 394 struct pollfd *pfds; 395 struct addrinfo hints, *res, *res0; 396 nfds_t n, i; 397 398 /* 399 * Detach from parent. 400 */ 401 if (daemon(1, 1) == -1) { 402 syslog(LOG_ERR, "failed to become a daemon"); 403 exit(1); 404 } 405 sa.sa_handler = reapchild; 406 (void) sigaction(SIGCHLD, &sa, NULL); 407 408 memset(&hints, 0, sizeof(hints)); 409 hints.ai_family = family; 410 hints.ai_socktype = SOCK_STREAM; 411 hints.ai_protocol = IPPROTO_TCP; 412 hints.ai_flags = AI_PASSIVE; 413 error = getaddrinfo(NULL, "ftp", &hints, &res0); 414 if (error) { 415 syslog(LOG_ERR, "%s", gai_strerror(error)); 416 exit(1); 417 } 418 419 n = 0; 420 for (res = res0; res; res = res->ai_next) 421 n++; 422 423 fds = calloc(n, sizeof(int)); 424 pfds = calloc(n, sizeof(struct pollfd)); 425 if (!fds || !pfds) { 426 syslog(LOG_ERR, "%s", strerror(errno)); 427 exit(1); 428 } 429 430 /* 431 * Open sockets, bind it to the FTP port, and start 432 * listening. 433 */ 434 n = 0; 435 for (res = res0; res; res = res->ai_next) { 436 fds[n] = socket(res->ai_family, res->ai_socktype, 437 res->ai_protocol); 438 if (fds[n] == -1) 439 continue; 440 441 if (setsockopt(fds[n], SOL_SOCKET, SO_KEEPALIVE, 442 &on, sizeof(on)) == -1) { 443 close(fds[n]); 444 fds[n] = -1; 445 continue; 446 } 447 448 if (setsockopt(fds[n], SOL_SOCKET, SO_REUSEADDR, 449 &on, sizeof(on)) == -1) { 450 close(fds[n]); 451 fds[n] = -1; 452 continue; 453 } 454 455 if (bind(fds[n], res->ai_addr, res->ai_addrlen) == -1) { 456 close(fds[n]); 457 fds[n] = -1; 458 continue; 459 } 460 if (listen(fds[n], 32) == -1) { 461 close(fds[n]); 462 fds[n] = -1; 463 continue; 464 } 465 466 pfds[n].fd = fds[n]; 467 pfds[n].events = POLLIN; 468 n++; 469 } 470 freeaddrinfo(res0); 471 472 if (n == 0) { 473 syslog(LOG_ERR, "could not open control socket"); 474 exit(1); 475 } 476 477 /* 478 * Loop forever accepting connection requests and forking off 479 * children to handle them. 480 */ 481 while (1) { 482 if (poll(pfds, n, INFTIM) == -1) { 483 if (errno == EINTR) 484 continue; 485 syslog(LOG_ERR, "poll: %m"); 486 exit(1); 487 } 488 for (i = 0; i < n; i++) 489 if (pfds[i].revents & POLLIN) { 490 addrlen = sizeof(his_addr); 491 fd = accept(pfds[i].fd, 492 (struct sockaddr *)&his_addr, 493 &addrlen); 494 if (fd != -1) { 495 if (fork() == 0) 496 goto child; 497 close(fd); 498 } 499 } 500 } 501 502 child: 503 /* child */ 504 (void)dup2(fd, STDIN_FILENO); 505 (void)dup2(fd, STDOUT_FILENO); 506 for (i = 0; i < n; i++) 507 close(fds[i]); 508 } else { 509 addrlen = sizeof(his_addr); 510 if (getpeername(0, (struct sockaddr *)&his_addr, 511 &addrlen) == -1) { 512 /* syslog(LOG_ERR, "getpeername (%s): %m", argv[0]); */ 513 exit(1); 514 } 515 } 516 517 /* set this here so klogin can use it... */ 518 (void)snprintf(ttyline, sizeof(ttyline), "ftp%ld", (long)getpid()); 519 520 set_slave_signals(); 521 522 addrlen = sizeof(ctrl_addr); 523 if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) == -1) { 524 syslog(LOG_ERR, "getsockname: %m"); 525 exit(1); 526 } 527 if (his_addr.su_family == AF_INET6 && 528 IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr)) { 529 syslog(LOG_WARNING, 530 "Connection from IPv4 mapped address is not supported."); 531 reply(530, "System not available."); 532 exit(1); 533 } 534 tos = IPTOS_LOWDELAY; 535 switch (his_addr.su_family) { 536 case AF_INET: 537 if (setsockopt(0, IPPROTO_IP, IP_TOS, &tos, 538 sizeof(int)) == -1) 539 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 540 break; 541 case AF_INET6: 542 if (setsockopt(0, IPPROTO_IPV6, IPV6_TCLASS, &tos, 543 sizeof(int)) == -1) 544 syslog(LOG_WARNING, "setsockopt (IPV6_TCLASS): %m"); 545 break; 546 } 547 data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1); 548 549 /* Try to handle urgent data inline */ 550 if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, &on, sizeof(on)) == -1) 551 syslog(LOG_ERR, "setsockopt: %m"); 552 553 dolog((struct sockaddr *)&his_addr); 554 555 /* 556 * Set up default state 557 */ 558 data = -1; 559 type = TYPE_A; 560 form = FORM_N; 561 stru = STRU_F; 562 mode = MODE_S; 563 tmpline[0] = '\0'; 564 565 /* If logins are disabled, print out the message. */ 566 if ((fp = fopen(_PATH_NOLOGIN, "r")) != NULL) { 567 while (fgets(line, sizeof(line), fp) != NULL) { 568 line[strcspn(line, "\n")] = '\0'; 569 lreply(530, "%s", line); 570 } 571 (void) fclose(fp); 572 reply(530, "System not available."); 573 exit(0); 574 } 575 if ((fp = fopen(_PATH_FTPWELCOME, "r")) != NULL) { 576 while (fgets(line, sizeof(line), fp) != NULL) { 577 line[strcspn(line, "\n")] = '\0'; 578 lreply(220, "%s", line); 579 } 580 (void) fclose(fp); 581 /* reply(220,) must follow */ 582 } 583 (void) gethostname(hostname, sizeof(hostname)); 584 585 /* Make sure hostname is fully qualified. */ 586 hp = gethostbyname(hostname); 587 if (hp != NULL) 588 strlcpy(hostname, hp->h_name, sizeof(hostname)); 589 590 if (multihome) { 591 error = getnameinfo((struct sockaddr *)&ctrl_addr, 592 ctrl_addr.su_len, dhostname, sizeof(dhostname), NULL, 0, 0); 593 } 594 595 if (error != 0) 596 reply(220, "FTP server ready."); 597 else 598 reply(220, "%s FTP server ready.", 599 (multihome ? dhostname : hostname)); 600 601 monitor_init(); 602 603 for (;;) 604 (void) yyparse(); 605 /* NOTREACHED */ 606} 607 608/* 609 * Signal handlers. 610 */ 611static void 612lostconn(int signo) 613{ 614 struct syslog_data sdata = SYSLOG_DATA_INIT; 615 616 sdata.log_fac = LOG_FTP; 617 if (debug) 618 syslog_r(LOG_DEBUG, &sdata, "lost connection"); 619 dologout(1); 620} 621 622static void 623sigquit(int signo) 624{ 625 struct syslog_data sdata = SYSLOG_DATA_INIT; 626 627 sdata.log_fac = LOG_FTP; 628 syslog_r(LOG_DEBUG, &sdata, "got signal %s", sys_signame[signo]); 629 dologout(1); 630} 631 632/* 633 * Save the result of a getpwnam. Used for USER command, since 634 * the data returned must not be clobbered by any other command 635 * (e.g., globbing). 636 */ 637static struct passwd * 638sgetpwnam(const char *name, struct passwd *pw) 639{ 640 static struct passwd *save; 641 struct passwd *old; 642 643 if (pw == NULL && (pw = getpwnam(name)) == NULL) 644 return (NULL); 645 old = save; 646 save = pw_dup(pw); 647 if (save == NULL) { 648 perror_reply(421, "Local resource failure: malloc"); 649 dologout(1); 650 /* NOTREACHED */ 651 } 652 if (old) { 653 explicit_bzero(old->pw_passwd, strlen(old->pw_passwd)); 654 free(old); 655 } 656 return (save); 657} 658 659static int login_attempts; /* number of failed login attempts */ 660static int askpasswd; /* had user command, ask for passwd */ 661static char curname[LOGIN_NAME_MAX]; /* current USER name */ 662 663/* 664 * USER command. 665 * Sets global passwd pointer pw if named account exists and is acceptable; 666 * sets askpasswd if a PASS command is expected. If logged in previously, 667 * need to reset state. If name is "ftp" or "anonymous", the name is not in 668 * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return. 669 * If account doesn't exist, ask for passwd anyway. Otherwise, check user 670 * requesting login privileges. Disallow anyone who does not have a standard 671 * shell as returned by getusershell(). Disallow anyone mentioned in the file 672 * _PATH_FTPUSERS to allow people such as root and uucp to be avoided. 673 */ 674void 675user(char *name) 676{ 677 char *cp, *shell, *style, *host; 678 char *class = NULL; 679 680 if (logged_in) { 681 kill_slave("user already logged in"); 682 end_login(); 683 } 684 685 /* Close session from previous user if there was one. */ 686 if (as) { 687 auth_close(as); 688 as = NULL; 689 } 690 if (lc) { 691 login_close(lc); 692 lc = NULL; 693 } 694 695 if ((style = strchr(name, ':')) != NULL) 696 *style++ = 0; 697 698 guest = 0; 699 askpasswd = 0; 700 host = multihome ? dhostname : hostname; 701 if (anon_ok && 702 (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0)) { 703 if (checkuser(_PATH_FTPUSERS, "ftp") || 704 checkuser(_PATH_FTPUSERS, "anonymous")) 705 reply(530, "User %s access denied.", name); 706 else if ((pw = sgetpwnam("ftp", NULL)) != NULL) { 707 if ((lc = login_getclass(pw->pw_class)) == NULL || 708 (as = auth_open()) == NULL || 709 auth_setpwd(as, pw) != 0 || 710 auth_setoption(as, "FTPD_HOST", host) < 0) { 711 if (as) { 712 auth_close(as); 713 as = NULL; 714 } 715 if (lc) { 716 login_close(lc); 717 lc = NULL; 718 } 719 reply(421, "Local resource failure"); 720 return; 721 } 722 guest = 1; 723 askpasswd = 1; 724 reply(331, 725 "Guest login ok, send your email address as password."); 726 } else 727 reply(530, "User %s unknown.", name); 728 if (!askpasswd && logging) 729 syslog(LOG_NOTICE, 730 "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost); 731 return; 732 } 733 734 shell = _PATH_BSHELL; 735 if ((pw = sgetpwnam(name, NULL))) { 736 class = pw->pw_class; 737 if (pw->pw_shell != NULL && *pw->pw_shell != '\0') 738 shell = pw->pw_shell; 739 while ((cp = getusershell()) != NULL) 740 if (strcmp(cp, shell) == 0) 741 break; 742 shell = cp; 743 endusershell(); 744 } 745 746 /* Get login class; if invalid style treat like unknown user. */ 747 lc = login_getclass(class); 748 if (lc && (style = login_getstyle(lc, style, "auth-ftp")) == NULL) { 749 login_close(lc); 750 lc = NULL; 751 pw = NULL; 752 } 753 754 /* Do pre-authentication setup. */ 755 if (lc && ((as = auth_open()) == NULL || 756 (pw != NULL && auth_setpwd(as, pw) != 0) || 757 auth_setitem(as, AUTHV_STYLE, style) < 0 || 758 auth_setitem(as, AUTHV_NAME, name) < 0 || 759 auth_setitem(as, AUTHV_CLASS, class) < 0 || 760 auth_setoption(as, "login", "yes") < 0 || 761 auth_setoption(as, "notickets", "yes") < 0 || 762 auth_setoption(as, "FTPD_HOST", host) < 0)) { 763 if (as) { 764 auth_close(as); 765 as = NULL; 766 } 767 login_close(lc); 768 lc = NULL; 769 reply(421, "Local resource failure"); 770 return; 771 } 772 if (logging) 773 strlcpy(curname, name, sizeof(curname)); 774 775 dochroot = (lc && login_getcapbool(lc, "ftp-chroot", 0)) || 776 checkuser(_PATH_FTPCHROOT, name); 777 if (anon_only && !dochroot) { 778 reply(530, "User %s access denied.", name); 779 return; 780 } 781 if (pw) { 782 if (pw->pw_uid < minuid) { 783 reply(530, "User %s access denied.", name); 784 if (logging) 785 syslog(LOG_NOTICE, 786 "FTP LOGIN REFUSED FROM %s, %s (UID))", 787 remotehost, name); 788 return; 789 } 790 if ((!shell && !dochroot) || checkuser(_PATH_FTPUSERS, name)) { 791 reply(530, "User %s access denied.", name); 792 if (logging) 793 syslog(LOG_NOTICE, 794 "FTP LOGIN REFUSED FROM %s, %s", 795 remotehost, name); 796 pw = NULL; 797 return; 798 } 799 } 800 801 if (as != NULL && (cp = auth_challenge(as)) != NULL) 802 reply(331, "%s", cp); 803 else 804 reply(331, "Password required for %s.", name); 805 806 askpasswd = 1; 807 /* 808 * Delay before reading passwd after first failed 809 * attempt to slow down passwd-guessing programs. 810 */ 811 if (login_attempts) 812 sleep((unsigned) login_attempts); 813} 814 815/* 816 * Check if a user is in the file "fname" 817 */ 818static int 819checkuser(char *fname, const char *name) 820{ 821 FILE *fp; 822 int found = 0; 823 char *p, line[BUFSIZ]; 824 825 if ((fp = fopen(fname, "r")) != NULL) { 826 while (fgets(line, sizeof(line), fp) != NULL) 827 if ((p = strchr(line, '\n')) != NULL) { 828 *p = '\0'; 829 if (line[0] == '#') 830 continue; 831 if (strcmp(line, name) == 0) { 832 found = 1; 833 break; 834 } 835 } 836 (void) fclose(fp); 837 } 838 return (found); 839} 840 841/* 842 * Terminate login as previous user, if any, resetting state; 843 * used when USER command is given or login fails. 844 */ 845static void 846end_login(void) 847{ 848 sigprocmask (SIG_BLOCK, &allsigs, NULL); 849 if (logged_in) { 850 if (!nowtmp) 851 ftpdlogwtmp(ttyline, "", ""); 852 if (doutmp) 853 ftpd_logout(utmp.ut_line); 854 } 855 reply(530, "Please reconnect to work as another user"); 856 _exit(0); 857} 858 859enum auth_ret 860pass(char *passwd) 861{ 862 int authok; 863 unsigned int flags; 864 FILE *fp; 865 static char homedir[PATH_MAX]; 866 char *motd, *dir, rootdir[PATH_MAX]; 867 size_t sz_pw_dir; 868 869 if (logged_in || askpasswd == 0) { 870 reply(503, "Login with USER first."); 871 return (AUTH_FAILED); 872 } 873 askpasswd = 0; 874 if (!guest) { /* "ftp" is only account allowed no password */ 875 authok = 0; 876 if (pw == NULL || pw->pw_passwd[0] == '\0') { 877 useconds_t us; 878 879 /* Sleep between 1 and 3 seconds to emulate a crypt. */ 880 us = arc4random_uniform(3000000); 881 usleep(us); 882 if (as != NULL) { 883 auth_close(as); 884 as = NULL; 885 } 886 } else { 887 authok = auth_userresponse(as, passwd, 0); 888 as = NULL; 889 } 890 if (authok == 0) { 891 reply(530, "Login incorrect."); 892 if (logging) 893 syslog(LOG_NOTICE, 894 "FTP LOGIN FAILED FROM %s, %s", 895 remotehost, curname); 896 pw = NULL; 897 if (login_attempts++ >= 5) { 898 syslog(LOG_NOTICE, 899 "repeated login failures from %s", 900 remotehost); 901 kill_slave("repeated login failures"); 902 _exit(0); 903 } 904 return (AUTH_FAILED); 905 } 906 } else if (lc != NULL) { 907 /* Save anonymous' password. */ 908 free(guestpw); 909 guestpw = strdup(passwd); 910 if (guestpw == NULL) { 911 kill_slave("out of mem"); 912 fatal("Out of memory."); 913 } 914 915 authok = auth_approval(as, lc, pw->pw_name, "ftp"); 916 auth_close(as); 917 as = NULL; 918 if (authok == 0) { 919 syslog(LOG_INFO|LOG_AUTH, 920 "FTP LOGIN FAILED (HOST) as %s: approval failure.", 921 pw->pw_name); 922 reply(530, "Approval failure."); 923 kill_slave("approval failure"); 924 _exit(0); 925 } 926 } else { 927 syslog(LOG_INFO|LOG_AUTH, 928 "FTP LOGIN CLASS %s MISSING for %s: approval failure.", 929 pw->pw_class, pw->pw_name); 930 reply(530, "Permission denied."); 931 kill_slave("permission denied"); 932 _exit(0); 933 } 934 935 if (monitor_post_auth() == 1) { 936 /* Post-auth monitor process */ 937 logged_in = 1; 938 return (AUTH_MONITOR); 939 } 940 941 login_attempts = 0; /* this time successful */ 942 /* set umask via setusercontext() unless -u flag was given. */ 943 flags = LOGIN_SETGROUP|LOGIN_SETPRIORITY|LOGIN_SETRESOURCES; 944 if (umaskchange) 945 flags |= LOGIN_SETUMASK; 946 else 947 (void) umask(defumask); 948 if (setusercontext(lc, pw, 0, flags) != 0) { 949 perror_reply(421, "Local resource failure: setusercontext"); 950 syslog(LOG_NOTICE, "setusercontext: %m"); 951 dologout(1); 952 /* NOTREACHED */ 953 } 954 955 /* open wtmp before chroot */ 956 if (!nowtmp) 957 ftpdlogwtmp(ttyline, pw->pw_name, remotehost); 958 959 /* open utmp before chroot */ 960 if (doutmp) { 961 memset(&utmp, 0, sizeof(utmp)); 962 (void)time(&utmp.ut_time); 963 (void)strncpy(utmp.ut_name, pw->pw_name, sizeof(utmp.ut_name)); 964 (void)strncpy(utmp.ut_host, remotehost, sizeof(utmp.ut_host)); 965 (void)strncpy(utmp.ut_line, ttyline, sizeof(utmp.ut_line)); 966 ftpd_login(&utmp); 967 } 968 969 /* open stats file before chroot */ 970 if (guest && (stats == 1) && (statfd < 0)) 971 if ((statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND)) == -1) 972 stats = 0; 973 974 logged_in = 1; 975 976 if ((dir = login_getcapstr(lc, "ftp-dir", NULL, NULL))) { 977 char *newdir; 978 979 newdir = copy_dir(dir, pw); 980 if (newdir == NULL) { 981 perror_reply(421, "Local resource failure: malloc"); 982 dologout(1); 983 /* NOTREACHED */ 984 } 985 pw->pw_dir = newdir; 986 pw = sgetpwnam(NULL, pw); 987 free(dir); 988 free(newdir); 989 } 990 991 /* make sure pw->pw_dir is big enough to hold "/" */ 992 sz_pw_dir = strlen(pw->pw_dir) + 1; 993 if (sz_pw_dir < 2) { 994 pw->pw_dir = "/"; 995 pw = sgetpwnam(NULL, pw); 996 sz_pw_dir = 2; 997 } 998 999 if (guest || dochroot) { 1000 if (multihome && guest) { 1001 struct stat ts; 1002 1003 /* Compute root directory. */ 1004 snprintf(rootdir, sizeof(rootdir), "%s/%s", 1005 pw->pw_dir, dhostname); 1006 if (stat(rootdir, &ts) == -1) { 1007 snprintf(rootdir, sizeof(rootdir), "%s/%s", 1008 pw->pw_dir, hostname); 1009 } 1010 } else 1011 strlcpy(rootdir, pw->pw_dir, sizeof(rootdir)); 1012 } 1013 if (guest) { 1014 /* 1015 * We MUST do a chdir() after the chroot. Otherwise 1016 * the old current directory will be accessible as "." 1017 * outside the new root! 1018 */ 1019 if (chroot(rootdir) == -1 || chdir("/") == -1) { 1020 reply(550, "Can't set guest privileges."); 1021 goto bad; 1022 } 1023 strlcpy(pw->pw_dir, "/", sz_pw_dir); 1024 if (setenv("HOME", "/", 1) == -1) { 1025 reply(550, "Can't setup environment."); 1026 goto bad; 1027 } 1028 } else if (dochroot) { 1029 if (chroot(rootdir) == -1 || chdir("/") == -1) { 1030 reply(550, "Can't change root."); 1031 goto bad; 1032 } 1033 strlcpy(pw->pw_dir, "/", sz_pw_dir); 1034 if (setenv("HOME", "/", 1) == -1) { 1035 reply(550, "Can't setup environment."); 1036 goto bad; 1037 } 1038 } else if (chdir(pw->pw_dir) == -1) { 1039 if (chdir("/") == -1) { 1040 reply(530, "User %s: can't change directory to %s.", 1041 pw->pw_name, pw->pw_dir); 1042 goto bad; 1043 } else 1044 lreply(230, "No directory! Logging in with home=/"); 1045 } 1046 if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) == -1) { 1047 reply(550, "Can't set gid."); 1048 goto bad; 1049 } 1050 if (setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) == -1) { 1051 reply(550, "Can't set uid."); 1052 goto bad; 1053 } 1054 sigprocmask(SIG_UNBLOCK, &allsigs, NULL); 1055 1056 /* 1057 * Set home directory so that use of ~ (tilde) works correctly. 1058 */ 1059 if (getcwd(homedir, PATH_MAX) != NULL) { 1060 if (setenv("HOME", homedir, 1) == -1) { 1061 reply(550, "Can't setup environment."); 1062 goto bad; 1063 } 1064 } 1065 1066 /* 1067 * Display a login message, if it exists. 1068 * N.B. reply(230,) must follow the message. 1069 */ 1070 motd = login_getcapstr(lc, "welcome", NULL, NULL); 1071 if ((fp = fopen(motd ? motd : _PATH_FTPLOGINMESG, "r")) != NULL) { 1072 char line[LINE_MAX]; 1073 1074 while (fgets(line, sizeof(line), fp) != NULL) { 1075 line[strcspn(line, "\n")] = '\0'; 1076 lreply(230, "%s", line); 1077 } 1078 (void) fclose(fp); 1079 } 1080 free(motd); 1081 if (guest) { 1082 reply(230, "Guest login ok, access restrictions apply."); 1083 snprintf(proctitle, sizeof(proctitle), 1084 "%s: anonymous/%.*s", remotehost, 1085 (int)(sizeof(proctitle) - sizeof(remotehost) - 1086 sizeof(": anonymous/")), passwd); 1087 setproctitle("%s", proctitle); 1088 if (logging) 1089 syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s", 1090 remotehost, passwd); 1091 } else { 1092 reply(230, "User %s logged in.", pw->pw_name); 1093 snprintf(proctitle, sizeof(proctitle), 1094 "%s: %s", remotehost, pw->pw_name); 1095 setproctitle("%s", proctitle); 1096 if (logging) 1097 syslog(LOG_INFO, "FTP LOGIN FROM %s as %s", 1098 remotehost, pw->pw_name); 1099 } 1100 login_close(lc); 1101 lc = NULL; 1102 return (AUTH_SLAVE); 1103bad: 1104 /* Forget all about it... */ 1105 login_close(lc); 1106 lc = NULL; 1107 end_login(); 1108 return (AUTH_FAILED); 1109} 1110 1111void 1112retrieve(enum ret_cmd cmd, const char *name) 1113{ 1114 FILE *fin, *dout; 1115 struct stat st; 1116 pid_t pid; 1117 time_t start; 1118 1119 if (cmd == RET_FILE) { 1120 fin = fopen(name, "r"); 1121 st.st_size = 0; 1122 } else { 1123 fin = ftpd_ls(name, &pid); 1124 st.st_size = -1; 1125 st.st_blksize = BUFSIZ; 1126 } 1127 if (fin == NULL) { 1128 if (errno != 0) { 1129 perror_reply(550, name); 1130 if (cmd == RET_FILE) { 1131 LOGCMD("get", name); 1132 } 1133 } 1134 return; 1135 } 1136 byte_count = -1; 1137 if (cmd == RET_FILE && 1138 (fstat(fileno(fin), &st) == -1 || !S_ISREG(st.st_mode))) { 1139 reply(550, "%s: not a plain file.", name); 1140 goto done; 1141 } 1142 if (restart_point) { 1143 if (type == TYPE_A) { 1144 off_t i, n; 1145 int c; 1146 1147 n = restart_point; 1148 i = 0; 1149 while (i++ < n) { 1150 if ((c = getc(fin)) == EOF) { 1151 if (ferror(fin)) { 1152 perror_reply(550, name); 1153 goto done; 1154 } else 1155 break; 1156 } 1157 if (c == '\n') 1158 i++; 1159 } 1160 } else if (lseek(fileno(fin), restart_point, SEEK_SET) == -1) { 1161 perror_reply(550, name); 1162 goto done; 1163 } 1164 } 1165 dout = dataconn(name, st.st_size, "w"); 1166 if (dout == NULL) 1167 goto done; 1168 time(&start); 1169 send_data(fin, dout, st.st_blksize, st.st_size, 1170 (restart_point == 0 && cmd == RET_FILE && S_ISREG(st.st_mode))); 1171 if ((cmd == RET_FILE) && stats) 1172 logxfer(name, byte_count, start); 1173 (void) fclose(dout); 1174 data = -1; 1175done: 1176 if (pdata >= 0) 1177 (void) close(pdata); 1178 pdata = -1; 1179 if (cmd == RET_FILE) { 1180 LOGBYTES("get", name, byte_count); 1181 fclose(fin); 1182 } else { 1183 ftpd_pclose(fin, pid); 1184 } 1185} 1186 1187void 1188store(const char *name, const char *mode, int unique) 1189{ 1190 FILE *fout, *din; 1191 int (*closefunc)(FILE *); 1192 struct stat st; 1193 int fd; 1194 1195 if (restart_point && *mode != 'a') 1196 mode = "r+"; 1197 1198 if (unique && stat(name, &st) == 0) { 1199 char *nam; 1200 1201 fd = guniquefd(name, &nam); 1202 if (fd == -1) { 1203 LOGCMD(*mode == 'w' ? "put" : "append", name); 1204 return; 1205 } 1206 name = nam; 1207 fout = fdopen(fd, mode); 1208 } else 1209 fout = fopen(name, mode); 1210 1211 closefunc = fclose; 1212 if (fout == NULL) { 1213 perror_reply(553, name); 1214 LOGCMD(*mode == 'w' ? "put" : "append", name); 1215 return; 1216 } 1217 byte_count = -1; 1218 if (restart_point) { 1219 if (type == TYPE_A) { 1220 off_t i, n; 1221 int c; 1222 1223 n = restart_point; 1224 i = 0; 1225 while (i++ < n) { 1226 if ((c = getc(fout)) == EOF) { 1227 if (ferror(fout)) { 1228 perror_reply(550, name); 1229 goto done; 1230 } else 1231 break; 1232 } 1233 if (c == '\n') 1234 i++; 1235 } 1236 /* 1237 * We must do this seek to "current" position 1238 * because we are changing from reading to 1239 * writing. 1240 */ 1241 if (fseek(fout, 0, SEEK_CUR) == -1) { 1242 perror_reply(550, name); 1243 goto done; 1244 } 1245 } else if (lseek(fileno(fout), restart_point, SEEK_SET) == -1) { 1246 perror_reply(550, name); 1247 goto done; 1248 } 1249 } 1250 din = dataconn(name, -1, "r"); 1251 if (din == NULL) 1252 goto done; 1253 if (receive_data(din, fout) == 0) { 1254 if (unique) 1255 reply(226, "Transfer complete (unique file name:%s).", 1256 name); 1257 else 1258 reply(226, "Transfer complete."); 1259 } 1260 (void) fclose(din); 1261 data = -1; 1262 pdata = -1; 1263done: 1264 LOGBYTES(*mode == 'w' ? "put" : "append", name, byte_count); 1265 (*closefunc)(fout); 1266} 1267 1268static FILE * 1269getdatasock(char *mode) 1270{ 1271 int opt, s, t, tries; 1272 1273 if (data >= 0) 1274 return (fdopen(data, mode)); 1275 sigprocmask (SIG_BLOCK, &allsigs, NULL); 1276 s = monitor_socket(ctrl_addr.su_family); 1277 if (s < 0) 1278 goto bad; 1279 opt = 1; 1280 if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, 1281 &opt, sizeof(opt)) == -1) 1282 goto bad; 1283 /* anchor socket to avoid multi-homing problems */ 1284 data_source = ctrl_addr; 1285 data_source.su_port = htons(20); /* ftp-data port */ 1286 for (tries = 1; ; tries++) { 1287 if (monitor_bind(s, (struct sockaddr *)&data_source, 1288 data_source.su_len) >= 0) 1289 break; 1290 if (errno != EADDRINUSE || tries > 10) 1291 goto bad; 1292 sleep((unsigned int)tries); 1293 } 1294 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1295 1296 opt = IPTOS_THROUGHPUT; 1297 switch (ctrl_addr.su_family) { 1298 case AF_INET: 1299 if (setsockopt(s, IPPROTO_IP, IP_TOS, &opt, 1300 sizeof(opt)) == -1) 1301 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 1302 break; 1303 case AF_INET6: 1304 if (setsockopt(s, IPPROTO_IPV6, IPV6_TCLASS, &opt, 1305 sizeof(opt)) == -1) 1306 syslog(LOG_WARNING, "setsockopt (IPV6_TCLASS): %m"); 1307 break; 1308 } 1309 /* 1310 * Turn off push flag to keep sender TCP from sending short packets 1311 * at the boundaries of each write(). Should probably do a SO_SNDBUF 1312 * to set the send buffer size as well, but that may not be desirable 1313 * in heavy-load situations. 1314 */ 1315 opt = 1; 1316 if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, &opt, sizeof(opt)) == -1) 1317 syslog(LOG_WARNING, "setsockopt (TCP_NOPUSH): %m"); 1318 opt = 65536; 1319 if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, &opt, sizeof(opt)) == -1) 1320 syslog(LOG_WARNING, "setsockopt (SO_SNDBUF): %m"); 1321 1322 return (fdopen(s, mode)); 1323bad: 1324 /* Return the real value of errno (close may change it) */ 1325 t = errno; 1326 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1327 if (s >= 0) 1328 (void) close(s); 1329 errno = t; 1330 return (NULL); 1331} 1332 1333static FILE * 1334dataconn(const char *name, off_t size, char *mode) 1335{ 1336 char sizebuf[32]; 1337 FILE *file = NULL; 1338 int retry = 0; 1339 in_port_t *p; 1340 u_char *fa, *ha; 1341 size_t alen; 1342 int error; 1343 1344 file_size = size; 1345 byte_count = 0; 1346 if (size != -1) { 1347 (void) snprintf(sizebuf, sizeof(sizebuf), " (%lld bytes)", 1348 (long long)size); 1349 } else 1350 sizebuf[0] = '\0'; 1351 if (pdata >= 0) { 1352 union sockunion from; 1353 int s; 1354 socklen_t fromlen = sizeof(from); 1355 1356 (void) alarm ((unsigned) timeout); 1357 s = accept(pdata, (struct sockaddr *)&from, &fromlen); 1358 (void) alarm (0); 1359 if (s == -1) { 1360 reply(425, "Can't open data connection."); 1361 (void) close(pdata); 1362 pdata = -1; 1363 return (NULL); 1364 } 1365 switch (from.su_family) { 1366 case AF_INET: 1367 p = (in_port_t *)&from.su_sin.sin_port; 1368 fa = (u_char *)&from.su_sin.sin_addr; 1369 ha = (u_char *)&his_addr.su_sin.sin_addr; 1370 alen = sizeof(struct in_addr); 1371 break; 1372 case AF_INET6: 1373 p = (in_port_t *)&from.su_sin6.sin6_port; 1374 fa = (u_char *)&from.su_sin6.sin6_addr; 1375 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1376 alen = sizeof(struct in6_addr); 1377 break; 1378 default: 1379 reply(425, "Can't build data connection: " 1380 "unknown address family"); 1381 (void) close(pdata); 1382 (void) close(s); 1383 pdata = -1; 1384 return (NULL); 1385 } 1386 if (from.su_family != his_addr.su_family || 1387 ntohs(*p) < IPPORT_RESERVED) { 1388 reply(425, "Can't build data connection: " 1389 "address family or port error"); 1390 (void) close(pdata); 1391 (void) close(s); 1392 pdata = -1; 1393 return (NULL); 1394 } 1395 if (portcheck && memcmp(fa, ha, alen) != 0) { 1396 reply(425, "Can't build data connection: " 1397 "illegal port number"); 1398 (void) close(pdata); 1399 (void) close(s); 1400 pdata = -1; 1401 return (NULL); 1402 } 1403 (void) close(pdata); 1404 pdata = s; 1405 reply(150, "Opening %s mode data connection for '%s'%s.", 1406 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1407 return (fdopen(pdata, mode)); 1408 } 1409 if (data >= 0) { 1410 reply(125, "Using existing data connection for '%s'%s.", 1411 name, sizebuf); 1412 usedefault = 1; 1413 return (fdopen(data, mode)); 1414 } 1415 if (usedefault) 1416 data_dest = his_addr; 1417 usedefault = 1; 1418 do { 1419 if (file != NULL) 1420 (void) fclose(file); 1421 file = getdatasock(mode); 1422 if (file == NULL) { 1423 char hbuf[HOST_NAME_MAX+1], pbuf[10]; 1424 1425 error = getnameinfo((struct sockaddr *)&data_source, 1426 data_source.su_len, hbuf, sizeof(hbuf), pbuf, 1427 sizeof(pbuf), NI_NUMERICHOST | NI_NUMERICSERV); 1428 if (error != 0) 1429 reply(425, "Can't create data socket: %s.", 1430 strerror(errno)); 1431 else 1432 reply(425, 1433 "Can't create data socket (%s,%s): %s.", 1434 hbuf, pbuf, strerror(errno)); 1435 return (NULL); 1436 } 1437 1438 /* 1439 * attempt to connect to reserved port on client machine; 1440 * this looks like an attack 1441 */ 1442 switch (data_dest.su_family) { 1443 case AF_INET: 1444 p = (in_port_t *)&data_dest.su_sin.sin_port; 1445 fa = (u_char *)&data_dest.su_sin.sin_addr; 1446 ha = (u_char *)&his_addr.su_sin.sin_addr; 1447 alen = sizeof(struct in_addr); 1448 break; 1449 case AF_INET6: 1450 p = (in_port_t *)&data_dest.su_sin6.sin6_port; 1451 fa = (u_char *)&data_dest.su_sin6.sin6_addr; 1452 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1453 alen = sizeof(struct in6_addr); 1454 break; 1455 default: 1456 reply(425, "Can't build data connection: " 1457 "unknown address family"); 1458 (void) fclose(file); 1459 pdata = -1; 1460 return (NULL); 1461 } 1462 if (data_dest.su_family != his_addr.su_family || 1463 ntohs(*p) < IPPORT_RESERVED || ntohs(*p) == 2049) { /* XXX */ 1464 reply(425, "Can't build data connection: " 1465 "address family or port error"); 1466 (void) fclose(file); 1467 return NULL; 1468 } 1469 if (portcheck && memcmp(fa, ha, alen) != 0) { 1470 reply(435, "Can't build data connection: " 1471 "illegal port number"); 1472 (void) fclose(file); 1473 return NULL; 1474 } 1475 1476 if (connect(fileno(file), (struct sockaddr *)&data_dest, 1477 data_dest.su_len) == 0) { 1478 reply(150, "Opening %s mode data connection for '%s'%s.", 1479 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1480 data = fileno(file); 1481 return (file); 1482 } 1483 if (errno != EADDRINUSE) 1484 break; 1485 sleep((unsigned) swaitint); 1486 retry += swaitint; 1487 } while (retry <= swaitmax); 1488 perror_reply(425, "Can't build data connection"); 1489 (void) fclose(file); 1490 return (NULL); 1491} 1492 1493/* 1494 * Transfer the contents of "instr" to "outstr" peer using the appropriate 1495 * encapsulation of the data subject to Mode, Structure, and Type. 1496 * 1497 * NB: Form isn't handled. 1498 */ 1499static int 1500send_data(FILE *instr, FILE *outstr, off_t blksize, off_t filesize, int isreg) 1501{ 1502 int c, cnt, filefd, netfd; 1503 char *buf, *bp; 1504 size_t len; 1505 1506 transflag++; 1507 switch (type) { 1508 1509 case TYPE_A: 1510 while ((c = getc(instr)) != EOF) { 1511 if (recvurg) 1512 goto got_oob; 1513 byte_count++; 1514 if (c == '\n') { 1515 if (ferror(outstr)) 1516 goto data_err; 1517 (void) putc('\r', outstr); 1518 } 1519 (void) putc(c, outstr); 1520 } 1521 fflush(outstr); 1522 transflag = 0; 1523 if (ferror(instr)) 1524 goto file_err; 1525 if (ferror(outstr)) 1526 goto data_err; 1527 reply(226, "Transfer complete."); 1528 return(0); 1529 1530 case TYPE_I: 1531 case TYPE_L: 1532 /* 1533 * isreg is only set if we are not doing restart and we 1534 * are sending a regular file 1535 */ 1536 netfd = fileno(outstr); 1537 filefd = fileno(instr); 1538 1539 if (isreg && filesize < 16 * 1024 * 1024) { 1540 size_t fsize = (size_t)filesize; 1541 1542 if (fsize == 0) { 1543 transflag = 0; 1544 reply(226, "Transfer complete."); 1545 return(0); 1546 } 1547 1548 buf = mmap(0, fsize, PROT_READ, MAP_SHARED, filefd, 0); 1549 if (buf == MAP_FAILED) { 1550 syslog(LOG_WARNING, "mmap(%llu): %m", 1551 (unsigned long long)fsize); 1552 goto oldway; 1553 } 1554 bp = buf; 1555 len = fsize; 1556 do { 1557 cnt = write(netfd, bp, len); 1558 if (recvurg) { 1559 munmap(buf, fsize); 1560 goto got_oob; 1561 } 1562 len -= cnt; 1563 bp += cnt; 1564 if (cnt > 0) 1565 byte_count += cnt; 1566 } while(cnt > 0 && len > 0); 1567 1568 transflag = 0; 1569 munmap(buf, fsize); 1570 if (cnt < 0) 1571 goto data_err; 1572 reply(226, "Transfer complete."); 1573 return(0); 1574 } 1575 1576oldway: 1577 if ((buf = malloc((size_t)blksize)) == NULL) { 1578 transflag = 0; 1579 perror_reply(451, "Local resource failure: malloc"); 1580 return(-1); 1581 } 1582 1583 while ((cnt = read(filefd, buf, (size_t)blksize)) > 0 && 1584 write(netfd, buf, cnt) == cnt) 1585 byte_count += cnt; 1586 transflag = 0; 1587 (void)free(buf); 1588 if (cnt != 0) { 1589 if (cnt == -1) 1590 goto file_err; 1591 goto data_err; 1592 } 1593 reply(226, "Transfer complete."); 1594 return(0); 1595 default: 1596 transflag = 0; 1597 reply(550, "Unimplemented TYPE %d in send_data", type); 1598 return(-1); 1599 } 1600 1601data_err: 1602 transflag = 0; 1603 reply(426, "Data connection"); 1604 return(-1); 1605 1606file_err: 1607 transflag = 0; 1608 reply(551, "Error on input file"); 1609 return(-1); 1610 1611got_oob: 1612 myoob(); 1613 recvurg = 0; 1614 transflag = 0; 1615 return(-1); 1616} 1617 1618/* 1619 * Transfer data from peer to "outstr" using the appropriate encapulation of 1620 * the data subject to Mode, Structure, and Type. 1621 * 1622 * N.B.: Form isn't handled. 1623 */ 1624static int 1625receive_data(FILE *instr, FILE *outstr) 1626{ 1627 int c; 1628 int cnt; 1629 char buf[BUFSIZ]; 1630 struct sigaction sa, sa_saved; 1631 volatile int bare_lfs = 0; 1632 1633 transflag++; 1634 switch (type) { 1635 1636 case TYPE_I: 1637 case TYPE_L: 1638 memset(&sa, 0, sizeof(sa)); 1639 sigfillset(&sa.sa_mask); 1640 sa.sa_flags = SA_RESTART; 1641 sa.sa_handler = lostconn; 1642 (void) sigaction(SIGALRM, &sa, &sa_saved); 1643 do { 1644 (void) alarm ((unsigned) timeout); 1645 cnt = read(fileno(instr), buf, sizeof(buf)); 1646 (void) alarm (0); 1647 if (recvurg) 1648 goto got_oob; 1649 1650 if (cnt > 0) { 1651 if (write(fileno(outstr), buf, cnt) != cnt) 1652 goto file_err; 1653 byte_count += cnt; 1654 } 1655 } while (cnt > 0); 1656 (void) sigaction(SIGALRM, &sa_saved, NULL); 1657 if (cnt == -1) 1658 goto data_err; 1659 transflag = 0; 1660 return (0); 1661 1662 case TYPE_E: 1663 reply(553, "TYPE E not implemented."); 1664 transflag = 0; 1665 return (-1); 1666 1667 case TYPE_A: 1668 while ((c = getc(instr)) != EOF) { 1669 if (recvurg) 1670 goto got_oob; 1671 byte_count++; 1672 if (c == '\n') 1673 bare_lfs++; 1674 while (c == '\r') { 1675 if (ferror(outstr)) 1676 goto data_err; 1677 if ((c = getc(instr)) != '\n') { 1678 (void) putc ('\r', outstr); 1679 if (c == '\0' || c == EOF) 1680 goto contin2; 1681 } 1682 } 1683 (void) putc(c, outstr); 1684 contin2: ; 1685 } 1686 fflush(outstr); 1687 if (ferror(instr)) 1688 goto data_err; 1689 if (ferror(outstr)) 1690 goto file_err; 1691 transflag = 0; 1692 if (bare_lfs) { 1693 lreply(226, 1694 "WARNING! %d bare linefeeds received in ASCII mode", 1695 bare_lfs); 1696 printf(" File may not have transferred correctly.\r\n"); 1697 } 1698 return (0); 1699 default: 1700 reply(550, "Unimplemented TYPE %d in receive_data", type); 1701 transflag = 0; 1702 return (-1); 1703 } 1704 1705data_err: 1706 transflag = 0; 1707 reply(426, "Data Connection"); 1708 return (-1); 1709 1710file_err: 1711 transflag = 0; 1712 reply(452, "Error writing file"); 1713 return (-1); 1714 1715got_oob: 1716 myoob(); 1717 recvurg = 0; 1718 transflag = 0; 1719 return (-1); 1720} 1721 1722void 1723statfilecmd(const char *filename) 1724{ 1725 FILE *fin; 1726 int c; 1727 int atstart; 1728 pid_t pid; 1729 fin = ftpd_ls(filename, &pid); 1730 if (fin == NULL) { 1731 reply(451, "Local resource failure"); 1732 return; 1733 } 1734 lreply(211, "status of %s:", filename); 1735 atstart = 1; 1736 while ((c = getc(fin)) != EOF) { 1737 if (c == '\n') { 1738 if (ferror(stdout)){ 1739 perror_reply(421, "control connection"); 1740 (void) ftpd_pclose(fin, pid); 1741 dologout(1); 1742 /* NOTREACHED */ 1743 } 1744 if (ferror(fin)) { 1745 perror_reply(551, filename); 1746 (void) ftpd_pclose(fin, pid); 1747 return; 1748 } 1749 (void) putc('\r', stdout); 1750 } 1751 if (atstart && isdigit(c)) 1752 (void) putc(' ', stdout); 1753 (void) putc(c, stdout); 1754 atstart = (c == '\n'); 1755 } 1756 (void) ftpd_pclose(fin, pid); 1757 reply(211, "End of Status"); 1758} 1759 1760void 1761statcmd(void) 1762{ 1763 union sockunion *su; 1764 u_char *a, *p; 1765 char hbuf[HOST_NAME_MAX+1]; 1766 int ispassive; 1767 int error; 1768 1769 lreply(211, "%s FTP server status:", hostname); 1770 error = getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len, 1771 hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST); 1772 printf(" Connected to %s", remotehost); 1773 if (error == 0 && strcmp(remotehost, hbuf) != 0) 1774 printf(" (%s)", hbuf); 1775 printf("\r\n"); 1776 if (logged_in) { 1777 if (guest) 1778 printf(" Logged in anonymously\r\n"); 1779 else 1780 printf(" Logged in as %s\r\n", pw->pw_name); 1781 } else if (askpasswd) 1782 printf(" Waiting for password\r\n"); 1783 else 1784 printf(" Waiting for user name\r\n"); 1785 printf(" TYPE: %s", typenames[type]); 1786 if (type == TYPE_A || type == TYPE_E) 1787 printf(", FORM: %s", formnames[form]); 1788 if (type == TYPE_L) 1789 printf(" 8"); 1790 printf("; STRUcture: %s; transfer MODE: %s\r\n", 1791 strunames[stru], modenames[mode]); 1792 ispassive = 0; 1793 if (data != -1) 1794 printf(" Data connection open\r\n"); 1795 else if (pdata != -1) { 1796 printf(" in Passive mode\r\n"); 1797 su = (union sockunion *)&pasv_addr; 1798 ispassive++; 1799 goto printaddr; 1800 } else if (usedefault == 0) { 1801 size_t alen, i; 1802 int af; 1803 1804 su = (union sockunion *)&data_dest; 1805printaddr: 1806 /* PASV/PORT */ 1807 if (su->su_family == AF_INET) { 1808 if (ispassive) 1809 printf("211- PASV "); 1810 else 1811 printf("211- PORT "); 1812 a = (u_char *)&su->su_sin.sin_addr; 1813 p = (u_char *)&su->su_sin.sin_port; 1814 printf("(%u,%u,%u,%u,%u,%u)\r\n", 1815 a[0], a[1], a[2], a[3], 1816 p[0], p[1]); 1817 } 1818 1819 /* LPSV/LPRT */ 1820 alen = 0; 1821 switch (su->su_family) { 1822 case AF_INET: 1823 a = (u_char *)&su->su_sin.sin_addr; 1824 p = (u_char *)&su->su_sin.sin_port; 1825 alen = sizeof(su->su_sin.sin_addr); 1826 af = 4; 1827 break; 1828 case AF_INET6: 1829 a = (u_char *)&su->su_sin6.sin6_addr; 1830 p = (u_char *)&su->su_sin6.sin6_port; 1831 alen = sizeof(su->su_sin6.sin6_addr); 1832 af = 6; 1833 break; 1834 default: 1835 af = 0; 1836 break; 1837 } 1838 if (af) { 1839 if (ispassive) 1840 printf("211- LPSV "); 1841 else 1842 printf("211- LPRT "); 1843 printf("(%u,%llu", af, (unsigned long long)alen); 1844 for (i = 0; i < alen; i++) 1845 printf(",%u", a[i]); 1846 printf(",%u,%u,%u)\r\n", 2, p[0], p[1]); 1847 } 1848 1849 /* EPRT/EPSV */ 1850 switch (su->su_family) { 1851 case AF_INET: 1852 af = 1; 1853 break; 1854 case AF_INET6: 1855 af = 2; 1856 break; 1857 default: 1858 af = 0; 1859 break; 1860 } 1861 if (af) { 1862 char pbuf[10]; 1863 union sockunion tmp = *su; 1864 1865 if (tmp.su_family == AF_INET6) 1866 tmp.su_sin6.sin6_scope_id = 0; 1867 if (getnameinfo((struct sockaddr *)&tmp, tmp.su_len, 1868 hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), 1869 NI_NUMERICHOST | NI_NUMERICSERV) == 0) { 1870 if (ispassive) 1871 printf("211- EPSV "); 1872 else 1873 printf("211- EPRT "); 1874 printf("(|%u|%s|%s|)\r\n", 1875 af, hbuf, pbuf); 1876 } 1877 } 1878 } else 1879 printf(" No data connection\r\n"); 1880 reply(211, "End of status"); 1881} 1882 1883void 1884fatal(const char *s) 1885{ 1886 1887 reply(451, "Error in server: %s", s); 1888 reply(221, "Closing connection due to server error."); 1889 dologout(0); 1890 /* NOTREACHED */ 1891} 1892 1893void 1894reply(int n, const char *fmt, ...) 1895{ 1896 char *buf, *p, *next; 1897 int rval; 1898 va_list ap; 1899 1900 va_start(ap, fmt); 1901 rval = vasprintf(&buf, fmt, ap); 1902 va_end(ap); 1903 if (rval == -1 || buf == NULL) { 1904 printf("421 Local resource failure: malloc\r\n"); 1905 fflush(stdout); 1906 dologout(1); 1907 } 1908 next = buf; 1909 while ((p = strsep(&next, "\n\r"))) { 1910 printf("%d%s %s\r\n", n, (next != NULL) ? "-" : "", p); 1911 if (debug) 1912 syslog(LOG_DEBUG, "<--- %d%s %s", n, 1913 (next != NULL) ? "-" : "", p); 1914 } 1915 (void)fflush(stdout); 1916 free(buf); 1917} 1918 1919 1920void 1921reply_r(int n, const char *fmt, ...) 1922{ 1923 char *p, *next; 1924 char msg[BUFSIZ]; 1925 char buf[BUFSIZ]; 1926 va_list ap; 1927 struct syslog_data sdata = SYSLOG_DATA_INIT; 1928 1929 sdata.log_fac = LOG_FTP; 1930 va_start(ap, fmt); 1931 vsnprintf(msg, sizeof(msg), fmt, ap); 1932 va_end(ap); 1933 1934 next = msg; 1935 1936 while ((p = strsep(&next, "\n\r"))) { 1937 snprintf(buf, sizeof(buf), "%d%s %s\r\n", n, 1938 (next != NULL) ? "-" : "", p); 1939 write(STDOUT_FILENO, buf, strlen(buf)); 1940 if (debug) { 1941 buf[strlen(buf) - 2] = '\0'; 1942 syslog_r(LOG_DEBUG, &sdata, "<--- %s", buf); 1943 } 1944 } 1945} 1946 1947void 1948lreply(int n, const char *fmt, ...) 1949{ 1950 va_list ap; 1951 1952 va_start(ap, fmt); 1953 (void)printf("%d- ", n); 1954 (void)vprintf(fmt, ap); 1955 va_end(ap); 1956 (void)printf("\r\n"); 1957 (void)fflush(stdout); 1958 if (debug) { 1959 va_start(ap, fmt); 1960 syslog(LOG_DEBUG, "<--- %d- ", n); 1961 vsyslog(LOG_DEBUG, fmt, ap); 1962 va_end(ap); 1963 } 1964} 1965 1966static void 1967ack(const char *s) 1968{ 1969 1970 reply(250, "%s command successful.", s); 1971} 1972 1973void 1974nack(const char *s) 1975{ 1976 1977 reply(502, "%s command not implemented.", s); 1978} 1979 1980void 1981yyerror(char *s) 1982{ 1983 cbuf[strcspn(cbuf, "\n")] = '\0'; 1984 reply(500, "'%s': command not understood.", cbuf); 1985} 1986 1987void 1988delete(const char *name) 1989{ 1990 struct stat st; 1991 1992 LOGCMD("delete", name); 1993 if (stat(name, &st) == -1) { 1994 perror_reply(550, name); 1995 return; 1996 } 1997 if ((st.st_mode&S_IFMT) == S_IFDIR) { 1998 if (rmdir(name) == -1) { 1999 perror_reply(550, name); 2000 return; 2001 } 2002 goto done; 2003 } 2004 if (unlink(name) == -1) { 2005 perror_reply(550, name); 2006 return; 2007 } 2008done: 2009 ack("DELE"); 2010} 2011 2012void 2013cwd(char *path) 2014{ 2015 FILE *message; 2016 2017 if (chdir(path) == -1) 2018 perror_reply(550, path); 2019 else { 2020 if ((message = fopen(_PATH_CWDMESG, "r")) != NULL) { 2021 char line[LINE_MAX]; 2022 2023 while (fgets(line, sizeof(line), message) != NULL) { 2024 line[strcspn(line, "\n")] = '\0'; 2025 lreply(250, "%s", line); 2026 } 2027 (void) fclose(message); 2028 } 2029 ack("CWD"); 2030 } 2031} 2032 2033void 2034replydirname(const char *name, const char *message) 2035{ 2036 char *p, *ep; 2037 char npath[PATH_MAX * 2]; 2038 2039 p = npath; 2040 ep = &npath[sizeof(npath) - 1]; 2041 while (*name) { 2042 if (*name == '"') { 2043 if (ep - p < 2) 2044 break; 2045 *p++ = *name++; 2046 *p++ = '"'; 2047 } else { 2048 if (ep - p < 1) 2049 break; 2050 *p++ = *name++; 2051 } 2052 } 2053 *p = '\0'; 2054 reply(257, "\"%s\" %s", npath, message); 2055} 2056 2057void 2058makedir(const char *name) 2059{ 2060 2061 LOGCMD("mkdir", name); 2062 if (mkdir(name, 0777) == -1) 2063 perror_reply(550, name); 2064 else 2065 replydirname(name, "directory created."); 2066} 2067 2068void 2069removedir(const char *name) 2070{ 2071 2072 LOGCMD("rmdir", name); 2073 if (rmdir(name) == -1) 2074 perror_reply(550, name); 2075 else 2076 ack("RMD"); 2077} 2078 2079void 2080pwd(void) 2081{ 2082 char path[PATH_MAX]; 2083 2084 if (getcwd(path, sizeof(path)) == NULL) 2085 perror_reply(550, "Can't get current directory"); 2086 else 2087 replydirname(path, "is current directory."); 2088} 2089 2090char * 2091renamefrom(char *name) 2092{ 2093 struct stat st; 2094 2095 if (stat(name, &st) == -1) { 2096 perror_reply(550, name); 2097 return (NULL); 2098 } 2099 reply(350, "File exists, ready for destination name"); 2100 return (name); 2101} 2102 2103void 2104renamecmd(const char *from, const char *to) 2105{ 2106 2107 LOGCMD2("rename", from, to); 2108 if (rename(from, to) == -1) 2109 perror_reply(550, "rename"); 2110 else 2111 ack("RNTO"); 2112} 2113 2114static void 2115dolog(struct sockaddr *sa) 2116{ 2117 char hbuf[sizeof(remotehost)]; 2118 2119 if (getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), NULL, 0, 0) == 0) 2120 (void) strlcpy(remotehost, hbuf, sizeof(remotehost)); 2121 else 2122 (void) strlcpy(remotehost, "unknown", sizeof(remotehost)); 2123 2124 snprintf(proctitle, sizeof(proctitle), "%s: connected", remotehost); 2125 setproctitle("%s", proctitle); 2126 2127 if (logging) { 2128 int error; 2129 error = getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), 2130 NULL, 0, NI_NUMERICHOST); 2131 syslog(LOG_INFO, "connection from %s [%s]", remotehost, 2132 error ? gai_strerror(error) : hbuf); 2133 } 2134} 2135 2136/* 2137 * Record logout in wtmp file and exit with supplied status. 2138 * NOTE: because this is called from signal handlers it cannot 2139 * use stdio (or call other functions that use stdio). 2140 */ 2141void 2142dologout(int status) 2143{ 2144 2145 transflag = 0; 2146 2147 if (logged_in) { 2148 sigprocmask(SIG_BLOCK, &allsigs, NULL); 2149 if (!nowtmp) 2150 ftpdlogwtmp(ttyline, "", ""); 2151 if (doutmp) 2152 ftpd_logout(utmp.ut_line); 2153 } 2154 /* beware of flushing buffers after a SIGPIPE */ 2155 _exit(status); 2156} 2157 2158static void 2159sigurg(int signo) 2160{ 2161 2162 recvurg = 1; 2163} 2164 2165static void 2166myoob(void) 2167{ 2168 char *cp; 2169 int ret; 2170 2171 /* only process if transfer occurring */ 2172 if (!transflag) 2173 return; 2174 cp = tmpline; 2175 ret = get_line(cp, sizeof(tmpline)-1); 2176 if (ret == -1) { 2177 reply(221, "You could at least say goodbye."); 2178 dologout(0); 2179 } else if (ret == -2) { 2180 /* Ignore truncated command */ 2181 return; 2182 } 2183 upper(cp); 2184 if (strcmp(cp, "ABOR\r\n") == 0) { 2185 tmpline[0] = '\0'; 2186 reply(426, "Transfer aborted. Data connection closed."); 2187 reply(226, "Abort successful"); 2188 } 2189 if (strcmp(cp, "STAT\r\n") == 0) { 2190 tmpline[0] = '\0'; 2191 if (file_size != -1) 2192 reply(213, "Status: %lld of %lld bytes transferred", 2193 (long long)byte_count, (long long)file_size); 2194 else 2195 reply(213, "Status: %lld bytes transferred", 2196 (long long)byte_count); 2197 } 2198} 2199 2200/* 2201 * Note: a response of 425 is not mentioned as a possible response to 2202 * the PASV command in RFC959. However, it has been blessed as 2203 * a legitimate response by Jon Postel in a telephone conversation 2204 * with Rick Adams on 25 Jan 89. 2205 */ 2206void 2207passive(void) 2208{ 2209 socklen_t len; 2210 int on = 1; 2211 u_char *p, *a; 2212 2213 if (pw == NULL) { 2214 reply(530, "Please login with USER and PASS"); 2215 return; 2216 } 2217 if (pdata >= 0) 2218 close(pdata); 2219 /* 2220 * XXX 2221 * At this point, it would be nice to have an algorithm that 2222 * inserted a growing delay in an attack scenario. Such a thing 2223 * would look like continual passive sockets being opened, but 2224 * nothing serious being done with them. They're not used to 2225 * move data; the entire attempt is just to use tcp FIN_WAIT 2226 * resources. 2227 */ 2228 pdata = socket(AF_INET, SOCK_STREAM, 0); 2229 if (pdata == -1) { 2230 perror_reply(425, "Can't open passive connection"); 2231 return; 2232 } 2233 2234 if (setsockopt(pdata, SOL_SOCKET, SO_KEEPALIVE, 2235 &on, sizeof(on)) == -1) 2236 goto pasv_error; 2237 2238 on = IP_PORTRANGE_HIGH; 2239 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2240 &on, sizeof(on)) == -1) 2241 goto pasv_error; 2242 2243 pasv_addr = ctrl_addr; 2244 pasv_addr.su_sin.sin_port = 0; 2245 if (bind(pdata, (struct sockaddr *)&pasv_addr, 2246 pasv_addr.su_len) == -1) 2247 goto pasv_error; 2248 2249 len = sizeof(pasv_addr); 2250 if (getsockname(pdata, (struct sockaddr *)&pasv_addr, &len) == -1) 2251 goto pasv_error; 2252 if (listen(pdata, 1) == -1) 2253 goto pasv_error; 2254 a = (u_char *)&pasv_addr.su_sin.sin_addr; 2255 p = (u_char *)&pasv_addr.su_sin.sin_port; 2256 2257 reply(227, "Entering Passive Mode (%u,%u,%u,%u,%u,%u)", a[0], 2258 a[1], a[2], a[3], p[0], p[1]); 2259 return; 2260 2261pasv_error: 2262 perror_reply(425, "Can't open passive connection"); 2263 (void) close(pdata); 2264 pdata = -1; 2265 return; 2266} 2267 2268int 2269epsvproto2af(int proto) 2270{ 2271 2272 switch (proto) { 2273 case 1: return AF_INET; 2274 case 2: return AF_INET6; 2275 default: return -1; 2276 } 2277} 2278 2279int 2280af2epsvproto(int af) 2281{ 2282 2283 switch (af) { 2284 case AF_INET: return 1; 2285 case AF_INET6: return 2; 2286 default: return -1; 2287 } 2288} 2289 2290/* 2291 * 228 Entering Long Passive Mode (af, hal, h1, h2, h3,..., pal, p1, p2...) 2292 * 229 Entering Extended Passive Mode (|||port|) 2293 */ 2294void 2295long_passive(const char *cmd, int pf) 2296{ 2297 socklen_t len; 2298 int on = 1; 2299 u_char *p, *a; 2300 2301 if (!logged_in) { 2302 syslog(LOG_NOTICE, "long passive but not logged in"); 2303 reply(503, "Login with USER first."); 2304 return; 2305 } 2306 2307 if (pf != PF_UNSPEC && ctrl_addr.su_family != pf) { 2308 /* 2309 * XXX 2310 * only EPRT/EPSV ready clients will understand this 2311 */ 2312 if (strcmp(cmd, "EPSV") != 0) 2313 reply(501, "Network protocol mismatch"); /*XXX*/ 2314 else 2315 epsv_protounsupp("Network protocol mismatch"); 2316 2317 return; 2318 } 2319 2320 if (pdata >= 0) 2321 close(pdata); 2322 /* 2323 * XXX 2324 * At this point, it would be nice to have an algorithm that 2325 * inserted a growing delay in an attack scenario. Such a thing 2326 * would look like continual passive sockets being opened, but 2327 * nothing serious being done with them. They not used to move 2328 * data; the entire attempt is just to use tcp FIN_WAIT 2329 * resources. 2330 */ 2331 pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 2332 if (pdata == -1) { 2333 perror_reply(425, "Can't open passive connection"); 2334 return; 2335 } 2336 2337 if (setsockopt(pdata, SOL_SOCKET, SO_KEEPALIVE, 2338 &on, sizeof(on)) == -1) 2339 goto pasv_error; 2340 2341 switch (ctrl_addr.su_family) { 2342 case AF_INET: 2343 on = IP_PORTRANGE_HIGH; 2344 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2345 &on, sizeof(on)) == -1) 2346 goto pasv_error; 2347 break; 2348 case AF_INET6: 2349 on = IPV6_PORTRANGE_HIGH; 2350 if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE, 2351 &on, sizeof(on)) == -1) 2352 goto pasv_error; 2353 break; 2354 } 2355 2356 pasv_addr = ctrl_addr; 2357 pasv_addr.su_port = 0; 2358 if (bind(pdata, (struct sockaddr *)&pasv_addr, pasv_addr.su_len) == -1) 2359 goto pasv_error; 2360 len = pasv_addr.su_len; 2361 if (getsockname(pdata, (struct sockaddr *)&pasv_addr, &len) == -1) 2362 goto pasv_error; 2363 if (listen(pdata, 1) == -1) 2364 goto pasv_error; 2365 p = (u_char *)&pasv_addr.su_port; 2366 2367 if (strcmp(cmd, "LPSV") == 0) { 2368 switch (pasv_addr.su_family) { 2369 case AF_INET: 2370 a = (u_char *)&pasv_addr.su_sin.sin_addr; 2371 reply(228, 2372 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2373 4, 4, a[0], a[1], a[2], a[3], 2, p[0], p[1]); 2374 return; 2375 case AF_INET6: 2376 a = (u_char *)&pasv_addr.su_sin6.sin6_addr; 2377 reply(228, 2378 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u," 2379 "%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2380 6, 16, a[0], a[1], a[2], a[3], a[4], 2381 a[5], a[6], a[7], a[8], a[9], a[10], 2382 a[11], a[12], a[13], a[14], a[15], 2383 2, p[0], p[1]); 2384 return; 2385 } 2386 } else if (strcmp(cmd, "EPSV") == 0) { 2387 switch (pasv_addr.su_family) { 2388 case AF_INET: 2389 case AF_INET6: 2390 reply(229, "Entering Extended Passive Mode (|||%u|)", 2391 ntohs(pasv_addr.su_port)); 2392 return; 2393 } 2394 } else { 2395 /* more proper error code? */ 2396 } 2397 2398 pasv_error: 2399 perror_reply(425, "Can't open passive connection"); 2400 (void) close(pdata); 2401 pdata = -1; 2402 return; 2403} 2404 2405/* 2406 * EPRT |proto|addr|port| 2407 */ 2408int 2409extended_port(const char *arg) 2410{ 2411 char *tmp = NULL; 2412 char *result[3]; 2413 char *p, *q; 2414 char delim; 2415 struct addrinfo hints; 2416 struct addrinfo *res = NULL; 2417 int i; 2418 unsigned long proto; 2419 2420 if (epsvall) { 2421 reply(501, "EPRT disallowed after EPSV ALL"); 2422 return -1; 2423 } 2424 2425 usedefault = 0; 2426 if (pdata >= 0) { 2427 (void) close(pdata); 2428 pdata = -1; 2429 } 2430 2431 tmp = strdup(arg); 2432 if (!tmp) { 2433 fatal("not enough core."); 2434 /*NOTREACHED*/ 2435 } 2436 p = tmp; 2437 delim = p[0]; 2438 p++; 2439 memset(result, 0, sizeof(result)); 2440 for (i = 0; i < 3; i++) { 2441 q = strchr(p, delim); 2442 if (!q || *q != delim) 2443 goto parsefail; 2444 *q++ = '\0'; 2445 result[i] = p; 2446 p = q; 2447 } 2448 2449 /* some more sanity check */ 2450 p = NULL; 2451 (void)strtoul(result[2], &p, 10); 2452 if (!*result[2] || *p) 2453 goto protounsupp; 2454 p = NULL; 2455 proto = strtoul(result[0], &p, 10); 2456 if (!*result[0] || *p) 2457 goto protounsupp; 2458 2459 memset(&hints, 0, sizeof(hints)); 2460 hints.ai_family = epsvproto2af((int)proto); 2461 if (hints.ai_family < 0) 2462 goto protounsupp; 2463 hints.ai_socktype = SOCK_STREAM; 2464 hints.ai_flags = AI_NUMERICHOST; /*no DNS*/ 2465 if (getaddrinfo(result[1], result[2], &hints, &res)) 2466 goto parsefail; 2467 if (res->ai_next) 2468 goto parsefail; 2469 if (sizeof(data_dest) < res->ai_addrlen) 2470 goto parsefail; 2471 memcpy(&data_dest, res->ai_addr, res->ai_addrlen); 2472 if (his_addr.su_family == AF_INET6 && 2473 data_dest.su_family == AF_INET6) { 2474 /* XXX more sanity checks! */ 2475 data_dest.su_sin6.sin6_scope_id = 2476 his_addr.su_sin6.sin6_scope_id; 2477 } 2478 if (pdata >= 0) { 2479 (void) close(pdata); 2480 pdata = -1; 2481 } 2482 reply(200, "EPRT command successful."); 2483 2484 free(tmp); 2485 if (res) 2486 freeaddrinfo(res); 2487 return 0; 2488 2489parsefail: 2490 reply(500, "Invalid argument, rejected."); 2491 usedefault = 1; 2492 free(tmp); 2493 if (res) 2494 freeaddrinfo(res); 2495 return -1; 2496 2497protounsupp: 2498 epsv_protounsupp("Protocol not supported"); 2499 usedefault = 1; 2500 free(tmp); 2501 if (res) 2502 freeaddrinfo(res); 2503 return -1; 2504} 2505 2506/* 2507 * 522 Protocol not supported (proto,...) 2508 * as we assume address family for control and data connections are the same, 2509 * we do not return the list of address families we support - instead, we 2510 * return the address family of the control connection. 2511 */ 2512void 2513epsv_protounsupp(const char *message) 2514{ 2515 int proto; 2516 2517 proto = af2epsvproto(ctrl_addr.su_family); 2518 if (proto < 0) 2519 reply(501, "%s", message); /*XXX*/ 2520 else 2521 reply(522, "%s, use (%d)", message, proto); 2522} 2523 2524/* 2525 * Generate unique name for file with basename "local". 2526 * The file named "local" is already known to exist. 2527 * Generates failure reply on error. 2528 */ 2529static int 2530guniquefd(const char *local, char **nam) 2531{ 2532 static char new[PATH_MAX]; 2533 struct stat st; 2534 size_t len; 2535 int count, fd; 2536 char *cp; 2537 2538 cp = strrchr(local, '/'); 2539 if (cp) 2540 *cp = '\0'; 2541 if (stat(cp ? local : ".", &st) == -1) { 2542 perror_reply(553, cp ? local : "."); 2543 return (-1); 2544 } 2545 if (cp) 2546 *cp = '/'; 2547 len = strlcpy(new, local, sizeof(new)); 2548 if (len+2+1 >= sizeof(new)-1) 2549 return (-1); 2550 cp = new + len; 2551 *cp++ = '.'; 2552 for (count = 1; count < 100; count++) { 2553 (void)snprintf(cp, sizeof(new) - (cp - new), "%d", count); 2554 fd = open(new, O_RDWR|O_CREAT|O_EXCL, 0666); 2555 if (fd == -1) 2556 continue; 2557 if (nam) 2558 *nam = new; 2559 return (fd); 2560 } 2561 reply(452, "Unique file name cannot be created."); 2562 return (-1); 2563} 2564 2565/* 2566 * Format and send reply containing system error number. 2567 */ 2568void 2569perror_reply(int code, const char *string) 2570{ 2571 2572 reply(code, "%s: %s.", string, strerror(errno)); 2573} 2574 2575static char *onefile[] = { 2576 "", 2577 0 2578}; 2579 2580void 2581send_file_list(char *whichf) 2582{ 2583 struct stat st; 2584 DIR *dirp = NULL; 2585 struct dirent *dir; 2586 FILE *dout = NULL; 2587 char **dirlist; 2588 char *dirname; 2589 int simple = 0; 2590 volatile int freeglob = 0; 2591 glob_t gl; 2592 size_t prefixlen; 2593 2594 if (strpbrk(whichf, "~{[*?") != NULL) { 2595 memset(&gl, 0, sizeof(gl)); 2596 freeglob = 1; 2597 if (glob(whichf, 2598 GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE|GLOB_LIMIT, 2599 0, &gl)) { 2600 reply(550, "not found"); 2601 goto out; 2602 } else if (gl.gl_pathc == 0) { 2603 errno = ENOENT; 2604 perror_reply(550, whichf); 2605 goto out; 2606 } 2607 dirlist = gl.gl_pathv; 2608 } else { 2609 onefile[0] = whichf; 2610 dirlist = onefile; 2611 simple = 1; 2612 } 2613 2614 while ((dirname = *dirlist++)) { 2615 if (stat(dirname, &st) == -1) { 2616 /* 2617 * If user typed "ls -l", etc, and the client 2618 * used NLST, do what the user meant. 2619 */ 2620 if (dirname[0] == '-' && *dirlist == NULL && 2621 transflag == 0) { 2622 retrieve(RET_FILE, dirname); 2623 goto out; 2624 } 2625 perror_reply(550, whichf); 2626 if (dout != NULL) { 2627 (void) fclose(dout); 2628 transflag = 0; 2629 data = -1; 2630 pdata = -1; 2631 } 2632 goto out; 2633 } 2634 2635 if (S_ISREG(st.st_mode)) { 2636 if (dout == NULL) { 2637 dout = dataconn("file list", -1, "w"); 2638 if (dout == NULL) 2639 goto out; 2640 transflag++; 2641 } 2642 fprintf(dout, "%s%s\n", dirname, 2643 type == TYPE_A ? "\r" : ""); 2644 byte_count += strlen(dirname) + 1; 2645 continue; 2646 } else if (!S_ISDIR(st.st_mode)) 2647 continue; 2648 2649 if ((dirp = opendir(dirname)) == NULL) 2650 continue; 2651 2652 if (dirname[0] == '.' && dirname[1] == '\0') 2653 prefixlen = 0; 2654 else 2655 prefixlen = strlen(dirname) + 1; 2656 while ((dir = readdir(dirp)) != NULL) { 2657 if (recvurg) { 2658 myoob(); 2659 recvurg = 0; 2660 transflag = 0; 2661 goto out; 2662 } 2663 2664 if (dir->d_name[0] == '.' && dir->d_namlen == 1) 2665 continue; 2666 if (dir->d_name[0] == '.' && dir->d_name[1] == '.' && 2667 dir->d_namlen == 2) 2668 continue; 2669 2670 /* 2671 * We have to do a stat to insure it's 2672 * not a directory or special file. 2673 */ 2674 if (simple || 2675 (fstatat(dirfd(dirp), dir->d_name, &st, 0) == 0 && 2676 S_ISREG(st.st_mode))) { 2677 if (dout == NULL) { 2678 dout = dataconn("file list", -1, "w"); 2679 if (dout == NULL) 2680 goto out; 2681 transflag++; 2682 } 2683 2684 if (prefixlen) { 2685 fprintf(dout, "%s/", dirname); 2686 byte_count += prefixlen; 2687 } 2688 fprintf(dout, "%s%s\n", dir->d_name, 2689 type == TYPE_A ? "\r" : ""); 2690 byte_count += dir->d_namlen + 1; 2691 } 2692 } 2693 (void) closedir(dirp); 2694 } 2695 2696 if (dout == NULL) 2697 reply(550, "No files found."); 2698 else if (ferror(dout) != 0) 2699 perror_reply(550, "Data connection"); 2700 else 2701 reply(226, "Transfer complete."); 2702 2703 transflag = 0; 2704 if (dout != NULL) 2705 (void) fclose(dout); 2706 else { 2707 if (pdata >= 0) 2708 close(pdata); 2709 } 2710 data = -1; 2711 pdata = -1; 2712out: 2713 if (freeglob) { 2714 freeglob = 0; 2715 globfree(&gl); 2716 } 2717} 2718 2719static void 2720reapchild(int signo) 2721{ 2722 int save_errno = errno; 2723 int rval; 2724 2725 do { 2726 rval = waitpid(-1, NULL, WNOHANG); 2727 } while (rval > 0 || (rval == -1 && errno == EINTR)); 2728 errno = save_errno; 2729} 2730 2731void 2732logxfer(const char *name, off_t size, time_t start) 2733{ 2734 char buf[400 + (HOST_NAME_MAX+1)*4 + PATH_MAX*4]; 2735 char dir[PATH_MAX], path[PATH_MAX], rpath[PATH_MAX]; 2736 char vremotehost[(HOST_NAME_MAX+1)*4], vpath[PATH_MAX*4]; 2737 char *vpw; 2738 time_t now; 2739 int len; 2740 2741 if ((statfd >= 0) && (getcwd(dir, sizeof(dir)) != NULL)) { 2742 char *cnow; 2743 2744 time(&now); 2745 cnow = ctime(&now); 2746 2747 vpw = malloc(strlen(guest ? guestpw : pw->pw_name) * 4 + 1); 2748 if (vpw == NULL) 2749 return; 2750 2751 snprintf(path, sizeof(path), "%s/%s", dir, name); 2752 if (realpath(path, rpath) == NULL) 2753 strlcpy(rpath, path, sizeof(rpath)); 2754 strvis(vpath, rpath, VIS_SAFE|VIS_NOSLASH); 2755 2756 strvis(vremotehost, remotehost, VIS_SAFE|VIS_NOSLASH); 2757 strvis(vpw, guest? guestpw : pw->pw_name, VIS_SAFE|VIS_NOSLASH); 2758 2759 len = snprintf(buf, sizeof(buf), 2760 "%.24s %lld %s %lld %s %c %s %c %c %s ftp %d %s %s\n", 2761 cnow ? cnow : "?", 2762 (long long)(now - start + (now == start)), 2763 vremotehost, (long long)size, vpath, 2764 ((type == TYPE_A) ? 'a' : 'b'), "*" /* none yet */, 2765 'o', ((guest) ? 'a' : 'r'), 2766 vpw, 0 /* none yet */, 2767 ((guest) ? "*" : pw->pw_name), dhostname); 2768 free(vpw); 2769 2770 if (len < 0 || len >= sizeof(buf)) { 2771 if ((len = strlen(buf)) == 0) 2772 return; /* should not happen */ 2773 buf[len - 1] = '\n'; 2774 } 2775 write(statfd, buf, len); 2776 } 2777} 2778 2779void 2780set_slave_signals(void) 2781{ 2782 struct sigaction sa; 2783 2784 sigemptyset(&sa.sa_mask); 2785 sa.sa_flags = SA_RESTART; 2786 2787 sa.sa_handler = SIG_DFL; 2788 (void) sigaction(SIGCHLD, &sa, NULL); 2789 2790 sa.sa_handler = sigurg; 2791 sa.sa_flags = 0; /* don't restart syscalls for SIGURG */ 2792 (void) sigaction(SIGURG, &sa, NULL); 2793 2794 sigfillset(&sa.sa_mask); /* block all signals in handler */ 2795 sa.sa_flags = SA_RESTART; 2796 sa.sa_handler = sigquit; 2797 (void) sigaction(SIGHUP, &sa, NULL); 2798 (void) sigaction(SIGINT, &sa, NULL); 2799 (void) sigaction(SIGQUIT, &sa, NULL); 2800 (void) sigaction(SIGTERM, &sa, NULL); 2801 2802 sa.sa_handler = lostconn; 2803 (void) sigaction(SIGPIPE, &sa, NULL); 2804 2805 sa.sa_handler = toolong; 2806 (void) sigaction(SIGALRM, &sa, NULL); 2807 2808 if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1) 2809 syslog(LOG_ERR, "fcntl F_SETOWN: %m"); 2810} 2811 2812/* 2813 * Allocate space and return a copy of the specified dir. 2814 * If 'dir' begins with a tilde (~), expand it. 2815 */ 2816char * 2817copy_dir(char *dir, struct passwd *pw) 2818{ 2819 char *cp; 2820 char *newdir; 2821 char *user = NULL; 2822 2823 /* Nothing to expand */ 2824 if (dir[0] != '~') 2825 return (strdup(dir)); 2826 2827 /* "dir" is of form ~user/some/dir, lookup user. */ 2828 if (dir[1] != '/' && dir[1] != '\0') { 2829 if ((cp = strchr(dir + 1, '/')) == NULL) 2830 cp = dir + strlen(dir); 2831 if ((user = malloc((size_t)(cp - dir))) == NULL) 2832 return (NULL); 2833 strlcpy(user, dir + 1, (size_t)(cp - dir)); 2834 2835 /* Only do lookup if it is a different user. */ 2836 if (strcmp(user, pw->pw_name) != 0) { 2837 if ((pw = getpwnam(user)) == NULL) { 2838 /* No such user, interpret literally */ 2839 free(user); 2840 return(strdup(dir)); 2841 } 2842 } 2843 free(user); 2844 } 2845 2846 /* 2847 * If there is no directory separator (/) then it is just pw_dir. 2848 * Otherwise, replace ~foo with pw_dir. 2849 */ 2850 if ((cp = strchr(dir + 1, '/')) == NULL) { 2851 newdir = strdup(pw->pw_dir); 2852 } else { 2853 if (asprintf(&newdir, "%s%s", pw->pw_dir, cp) == -1) 2854 return (NULL); 2855 } 2856 2857 return(newdir); 2858} 2859