ftpd.c revision 1.151
1/* $OpenBSD: ftpd.c,v 1.151 2003/12/09 22:55:47 deraadt 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#ifndef lint 63static const char copyright[] = 64"@(#) Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994\n\ 65 The Regents of the University of California. All rights reserved.\n"; 66#endif /* not lint */ 67 68#ifndef lint 69#if 0 70static const char sccsid[] = "@(#)ftpd.c 8.4 (Berkeley) 4/16/94"; 71#else 72static const char rcsid[] = 73 "$OpenBSD: ftpd.c,v 1.151 2003/12/09 22:55:47 deraadt Exp $"; 74#endif 75#endif /* not lint */ 76 77/* 78 * FTP server. 79 */ 80#include <sys/param.h> 81#include <sys/stat.h> 82#include <sys/ioctl.h> 83#include <sys/socket.h> 84#include <sys/wait.h> 85#include <sys/mman.h> 86 87#include <netinet/in.h> 88#include <netinet/in_systm.h> 89#include <netinet/ip.h> 90#include <netinet/tcp.h> 91 92#define FTP_NAMES 93#include <arpa/ftp.h> 94#include <arpa/inet.h> 95#include <arpa/telnet.h> 96 97#include <bsd_auth.h> 98#include <ctype.h> 99#include <dirent.h> 100#include <err.h> 101#include <errno.h> 102#include <fcntl.h> 103#include <glob.h> 104#include <limits.h> 105#include <login_cap.h> 106#include <netdb.h> 107#include <pwd.h> 108#include <signal.h> 109#include <stdarg.h> 110#include <stdio.h> 111#include <stdlib.h> 112#include <string.h> 113#include <syslog.h> 114#include <time.h> 115#include <vis.h> 116#include <unistd.h> 117#include <util.h> 118#include <utmp.h> 119#include <poll.h> 120 121#if defined(TCPWRAPPERS) 122#include <tcpd.h> 123#endif /* TCPWRAPPERS */ 124 125#include "pathnames.h" 126#include "extern.h" 127 128static char version[] = "Version 6.5/OpenBSD"; 129 130extern off_t restart_point; 131extern char cbuf[]; 132 133union sockunion server_addr; 134union sockunion ctrl_addr; 135union sockunion data_source; 136union sockunion data_dest; 137union sockunion his_addr; 138union sockunion pasv_addr; 139 140sigset_t allsigs; 141 142int daemon_mode = 0; 143int data; 144int logged_in; 145struct passwd *pw; 146int debug = 0; 147int timeout = 900; /* timeout after 15 minutes of inactivity */ 148int maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */ 149int logging; 150int anon_ok = 1; 151int anon_only = 0; 152int multihome = 0; 153int guest; 154int stats; 155int statfd = -1; 156int portcheck = 1; 157int dochroot; 158int type; 159int form; 160int stru; /* avoid C keyword */ 161int mode; 162int doutmp = 0; /* update utmp file */ 163int usedefault = 1; /* for data transfers */ 164int pdata = -1; /* for passive mode */ 165int family = AF_UNSPEC; 166volatile sig_atomic_t transflag; 167off_t file_size; 168off_t byte_count; 169#if !defined(CMASK) || CMASK == 0 170#undef CMASK 171#define CMASK 022 172#endif 173int defumask = CMASK; /* default umask value */ 174int umaskchange = 1; /* allow user to change umask value. */ 175char tmpline[7]; 176char hostname[MAXHOSTNAMELEN]; 177char remotehost[MAXHOSTNAMELEN]; 178char dhostname[MAXHOSTNAMELEN]; 179char *guestpw; 180static char ttyline[20]; 181char *tty = ttyline; /* for klogin */ 182static struct utmp utmp; /* for utmp */ 183static login_cap_t *lc; 184static auth_session_t *as; 185static volatile sig_atomic_t recvurg; 186 187#if defined(TCPWRAPPERS) 188int allow_severity = LOG_INFO; 189int deny_severity = LOG_NOTICE; 190#endif /* TCPWRAPPERS */ 191 192char *ident = NULL; 193 194 195int epsvall = 0; 196 197/* 198 * Timeout intervals for retrying connections 199 * to hosts that don't accept PORT cmds. This 200 * is a kludge, but given the problems with TCP... 201 */ 202#define SWAITMAX 90 /* wait at most 90 seconds */ 203#define SWAITINT 5 /* interval between retries */ 204 205int swaitmax = SWAITMAX; 206int swaitint = SWAITINT; 207 208#ifdef HASSETPROCTITLE 209char proctitle[BUFSIZ]; /* initial part of title */ 210#endif /* HASSETPROCTITLE */ 211 212#define LOGCMD(cmd, file) \ 213 if (logging > 1) \ 214 syslog(LOG_INFO,"%s %s%s", cmd, \ 215 *(file) == '/' ? "" : curdir(), file); 216#define LOGCMD2(cmd, file1, file2) \ 217 if (logging > 1) \ 218 syslog(LOG_INFO,"%s %s%s %s%s", cmd, \ 219 *(file1) == '/' ? "" : curdir(), file1, \ 220 *(file2) == '/' ? "" : curdir(), file2); 221#define LOGBYTES(cmd, file, cnt) \ 222 if (logging > 1) { \ 223 if (cnt == (off_t)-1) \ 224 syslog(LOG_INFO,"%s %s%s", cmd, \ 225 *(file) == '/' ? "" : curdir(), file); \ 226 else \ 227 syslog(LOG_INFO, "%s %s%s = %qd bytes", \ 228 cmd, (*(file) == '/') ? "" : curdir(), file, cnt); \ 229 } 230 231static void ack(char *); 232static void sigurg(int); 233static void myoob(void); 234static int checkuser(char *, char *); 235static FILE *dataconn(char *, off_t, char *); 236static void dolog(struct sockaddr *); 237static char *copy_dir(char *, struct passwd *); 238static char *curdir(void); 239static void end_login(void); 240static FILE *getdatasock(char *); 241static int guniquefd(char *, char **); 242static void lostconn(int); 243static void sigquit(int); 244static int receive_data(FILE *, FILE *); 245static void replydirname(const char *, const char *); 246static int send_data(FILE *, FILE *, off_t, off_t, int); 247static struct passwd * 248 sgetpwnam(char *, struct passwd *); 249static void reapchild(int); 250#if defined(TCPWRAPPERS) 251static int check_host(struct sockaddr *); 252#endif /* TCPWRAPPERS */ 253static void usage(void); 254 255void logxfer(char *, off_t, time_t); 256 257static char * 258curdir(void) 259{ 260 static char path[MAXPATHLEN+1]; /* path + '/' */ 261 262 if (getcwd(path, sizeof(path)-1) == NULL) 263 return (""); 264 if (path[1] != '\0') /* special case for root dir. */ 265 strlcat(path, "/", sizeof path); 266 /* For guest account, skip / since it's chrooted */ 267 return (guest ? path+1 : path); 268} 269 270char *argstr = "AdDhnlMSt:T:u:UvP46"; 271 272static void 273usage(void) 274{ 275 syslog(LOG_ERR, 276 "usage: ftpd [-46ADdlMnPSU] [-T maxtimeout] [-t timeout] [-u mask]"); 277 exit(2); 278} 279 280int 281main(int argc, char *argv[]) 282{ 283 socklen_t addrlen; 284 int ch, on = 1, tos; 285 char *cp, line[LINE_MAX]; 286 FILE *fp; 287 struct hostent *hp; 288 struct sigaction sa; 289 290 tzset(); /* in case no timezone database in ~ftp */ 291 sigfillset(&allsigs); /* used to block signals while root */ 292 sigemptyset(&sa.sa_mask); 293 sa.sa_flags = SA_RESTART; 294 295 while ((ch = getopt(argc, argv, argstr)) != -1) { 296 switch (ch) { 297 case 'A': 298 anon_only = 1; 299 break; 300 301 case 'd': 302 case 'v': /* deprecated */ 303 debug = 1; 304 break; 305 306 case 'D': 307 daemon_mode = 1; 308 break; 309 310 case 'P': 311 portcheck = 0; 312 break; 313 314 case 'h': /* deprecated */ 315 break; 316 317 case 'l': 318 logging++; /* > 1 == extra logging */ 319 break; 320 321 case 'M': 322 multihome = 1; 323 break; 324 325 case 'n': 326 anon_ok = 0; 327 break; 328 329 case 'S': 330 stats = 1; 331 break; 332 333 case 't': 334 timeout = atoi(optarg); 335 if (maxtimeout < timeout) 336 maxtimeout = timeout; 337 break; 338 339 case 'T': 340 maxtimeout = atoi(optarg); 341 if (timeout > maxtimeout) 342 timeout = maxtimeout; 343 break; 344 345 case 'u': 346 { 347 long val = 0; 348 char *p; 349 umaskchange = 0; 350 351 val = strtol(optarg, &p, 8); 352 if (*p != '\0' || val < 0 || (val & ~ACCESSPERMS)) { 353 syslog(LOG_ERR, 354 "ftpd: %s is a bad value for -u, aborting..", 355 optarg); 356 exit(2); 357 } else 358 defumask = val; 359 break; 360 } 361 362 case 'U': 363 doutmp = 1; 364 break; 365 366 case '4': 367 family = AF_INET; 368 break; 369 370 case '6': 371 family = AF_INET6; 372 break; 373 374 default: 375 usage(); 376 break; 377 } 378 } 379 380 (void) freopen(_PATH_DEVNULL, "w", stderr); 381 382 /* 383 * LOG_NDELAY sets up the logging connection immediately, 384 * necessary for anonymous ftp's that chroot and can't do it later. 385 */ 386 openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP); 387 388 if (daemon_mode) { 389 int *fds, n, error, i, fd; 390 struct pollfd *pfds; 391 struct addrinfo hints, *res, *res0; 392 393 /* 394 * Detach from parent. 395 */ 396 if (daemon(1, 1) < 0) { 397 syslog(LOG_ERR, "failed to become a daemon"); 398 exit(1); 399 } 400 sa.sa_handler = reapchild; 401 (void) sigaction(SIGCHLD, &sa, NULL); 402 403 memset(&hints, 0, sizeof(hints)); 404 hints.ai_family = family; 405 hints.ai_socktype = SOCK_STREAM; 406 hints.ai_protocol = IPPROTO_TCP; 407 hints.ai_flags = AI_PASSIVE; 408 error = getaddrinfo(NULL, "ftp", &hints, &res0); 409 if (error) { 410 syslog(LOG_ERR, "%s", gai_strerror(error)); 411 exit(1); 412 } 413 414 n = 0; 415 for (res = res0; res; res = res->ai_next) 416 n++; 417 418 fds = malloc(n * sizeof(int)); 419 pfds = malloc(n * sizeof(struct pollfd)); 420 if (!fds || !pfds) { 421 syslog(LOG_ERR, "%s", strerror(errno)); 422 exit(1); 423 } 424 425 /* 426 * Open sockets, bind it to the FTP port, and start 427 * listening. 428 */ 429 n = 0; 430 for (res = res0; res; res = res->ai_next) { 431 fds[n] = socket(res->ai_family, res->ai_socktype, 432 res->ai_protocol); 433 if (fds[n] < 0) 434 continue; 435 436 if (setsockopt(fds[n], SOL_SOCKET, SO_REUSEADDR, 437 (char *)&on, sizeof(on)) < 0) { 438 close(fds[n]); 439 fds[n] = -1; 440 continue; 441 } 442 443 if (bind(fds[n], res->ai_addr, res->ai_addrlen) < 0) { 444 close(fds[n]); 445 fds[n] = -1; 446 continue; 447 } 448 if (listen(fds[n], 32) < 0) { 449 close(fds[n]); 450 fds[n] = -1; 451 continue; 452 } 453 454 pfds[n].fd = fds[n]; 455 pfds[n].events = POLLIN; 456 n++; 457 } 458 freeaddrinfo(res0); 459 460 if (n == 0) { 461 syslog(LOG_ERR, "could not open control socket"); 462 exit(1); 463 } 464 465 /* Stash pid in pidfile */ 466 if (pidfile(NULL)) 467 syslog(LOG_ERR, "can't open pidfile: %m"); 468 /* 469 * Loop forever accepting connection requests and forking off 470 * children to handle them. 471 */ 472 while (1) { 473 if (poll(pfds, n, INFTIM) < 0) { 474 if (errno == EINTR) 475 continue; 476 err(1, "poll"); 477 } 478 for (i = 0; i < n; i++) 479 if (pfds[i].revents & POLLIN) { 480 addrlen = sizeof(his_addr); 481 fd = accept(pfds[i].fd, 482 (struct sockaddr *)&his_addr, 483 &addrlen); 484 if (fork() == 0) 485 goto child; 486 close(fd); 487 } 488 } 489 490 child: 491 /* child */ 492 (void)dup2(fd, STDIN_FILENO); 493 (void)dup2(fd, STDOUT_FILENO); 494 for (i = 0; i < n; i++) 495 close(fds[i]); 496#if defined(TCPWRAPPERS) 497 /* ..in the child. */ 498 if (!check_host((struct sockaddr *)&his_addr)) 499 exit(1); 500#endif /* TCPWRAPPERS */ 501 } else { 502 addrlen = sizeof(his_addr); 503 if (getpeername(0, (struct sockaddr *)&his_addr, 504 &addrlen) < 0) { 505 /* syslog(LOG_ERR, "getpeername (%s): %m", argv[0]); */ 506 exit(1); 507 } 508 } 509 510 /* set this here so klogin can use it... */ 511 (void)snprintf(ttyline, sizeof(ttyline), "ftp%ld", (long)getpid()); 512 513 sa.sa_handler = SIG_DFL; 514 (void) sigaction(SIGCHLD, &sa, NULL); 515 516 sa.sa_handler = sigurg; 517 sa.sa_flags = 0; /* don't restart syscalls for SIGURG */ 518 (void) sigaction(SIGURG, &sa, NULL); 519 520 sigfillset(&sa.sa_mask); /* block all signals in handler */ 521 sa.sa_flags = SA_RESTART; 522 sa.sa_handler = sigquit; 523 (void) sigaction(SIGHUP, &sa, NULL); 524 (void) sigaction(SIGINT, &sa, NULL); 525 (void) sigaction(SIGQUIT, &sa, NULL); 526 (void) sigaction(SIGTERM, &sa, NULL); 527 528 sa.sa_handler = lostconn; 529 (void) sigaction(SIGPIPE, &sa, NULL); 530 531 sa.sa_handler = toolong; 532 (void) sigaction(SIGALRM, &sa, NULL); 533 534 addrlen = sizeof(ctrl_addr); 535 if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) { 536 syslog(LOG_ERR, "getsockname: %m"); 537 exit(1); 538 } 539 if (his_addr.su_family == AF_INET6 540 && IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr)) { 541#if 1 542 /* 543 * IPv4 control connection arrived to AF_INET6 socket. 544 * I hate to do this, but this is the easiest solution. 545 */ 546 union sockunion tmp_addr; 547 const int off = sizeof(struct in6_addr) - sizeof(struct in_addr); 548 549 tmp_addr = his_addr; 550 memset(&his_addr, 0, sizeof(his_addr)); 551 his_addr.su_sin.sin_family = AF_INET; 552 his_addr.su_sin.sin_len = sizeof(his_addr.su_sin); 553 memcpy(&his_addr.su_sin.sin_addr, 554 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 555 sizeof(his_addr.su_sin.sin_addr)); 556 his_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 557 558 tmp_addr = ctrl_addr; 559 memset(&ctrl_addr, 0, sizeof(ctrl_addr)); 560 ctrl_addr.su_sin.sin_family = AF_INET; 561 ctrl_addr.su_sin.sin_len = sizeof(ctrl_addr.su_sin); 562 memcpy(&ctrl_addr.su_sin.sin_addr, 563 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 564 sizeof(ctrl_addr.su_sin.sin_addr)); 565 ctrl_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 566#else 567 while (fgets(line, sizeof(line), fd) != NULL) { 568 if ((cp = strchr(line, '\n')) != NULL) 569 *cp = '\0'; 570 lreply(530, "%s", line); 571 } 572 (void) fflush(stdout); 573 (void) fclose(fd); 574 reply(530, 575 "Connection from IPv4 mapped address is not supported."); 576 exit(0); 577#endif 578 } 579#ifdef IP_TOS 580 if (his_addr.su_family == AF_INET) { 581 tos = IPTOS_LOWDELAY; 582 if (setsockopt(0, IPPROTO_IP, IP_TOS, (char *)&tos, 583 sizeof(int)) < 0) 584 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 585 } 586#endif 587 data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1); 588 589 /* Try to handle urgent data inline */ 590#ifdef SO_OOBINLINE 591 if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, (char *)&on, sizeof(on)) < 0) 592 syslog(LOG_ERR, "setsockopt: %m"); 593#endif 594 595#ifdef F_SETOWN 596 if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1) 597 syslog(LOG_ERR, "fcntl F_SETOWN: %m"); 598#endif 599 dolog((struct sockaddr *)&his_addr); 600 /* 601 * Set up default state 602 */ 603 data = -1; 604 type = TYPE_A; 605 form = FORM_N; 606 stru = STRU_F; 607 mode = MODE_S; 608 tmpline[0] = '\0'; 609 610 /* If logins are disabled, print out the message. */ 611 if ((fp = fopen(_PATH_NOLOGIN, "r")) != NULL) { 612 while (fgets(line, sizeof(line), fp) != NULL) { 613 if ((cp = strchr(line, '\n')) != NULL) 614 *cp = '\0'; 615 lreply(530, "%s", line); 616 } 617 (void) fflush(stdout); 618 (void) fclose(fp); 619 reply(530, "System not available."); 620 exit(0); 621 } 622 if ((fp = fopen(_PATH_FTPWELCOME, "r")) != NULL) { 623 while (fgets(line, sizeof(line), fp) != NULL) { 624 if ((cp = strchr(line, '\n')) != NULL) 625 *cp = '\0'; 626 lreply(220, "%s", line); 627 } 628 (void) fflush(stdout); 629 (void) fclose(fp); 630 /* reply(220,) must follow */ 631 } 632 (void) gethostname(hostname, sizeof(hostname)); 633 634 /* Make sure hostname is fully qualified. */ 635 hp = gethostbyname(hostname); 636 if (hp != NULL) 637 strlcpy(hostname, hp->h_name, sizeof(hostname)); 638 639 if (multihome) { 640 getnameinfo((struct sockaddr *)&ctrl_addr, ctrl_addr.su_len, 641 dhostname, sizeof(dhostname), NULL, 0, 0); 642 } 643 644 reply(220, "%s FTP server (%s) ready.", 645 (multihome ? dhostname : hostname), version); 646 for (;;) 647 (void) yyparse(); 648 /* NOTREACHED */ 649} 650 651/* 652 * Signal handlers. 653 */ 654 655static void 656lostconn(int signo) 657{ 658 struct syslog_data sdata = SYSLOG_DATA_INIT; 659 660 if (debug) 661 syslog_r(LOG_DEBUG, &sdata, "lost connection"); 662 dologout(1); 663} 664 665static void 666sigquit(int signo) 667{ 668 struct syslog_data sdata = SYSLOG_DATA_INIT; 669 670 syslog_r(LOG_ERR, &sdata, "got signal %s", sys_signame[signo]); 671 dologout(1); 672} 673 674/* 675 * Save the result of a getpwnam. Used for USER command, since 676 * the data returned must not be clobbered by any other command 677 * (e.g., globbing). 678 */ 679static struct passwd * 680sgetpwnam(char *name, struct passwd *pw) 681{ 682 static struct passwd *save; 683 struct passwd *old; 684 685 if (pw == NULL && (pw = getpwnam(name)) == NULL) 686 return (NULL); 687 old = save; 688 save = pw_dup(pw); 689 if (save == NULL) { 690 perror_reply(421, "Local resource failure: malloc"); 691 dologout(1); 692 /* NOTREACHED */ 693 } 694 if (old) { 695 memset(old->pw_passwd, 0, strlen(old->pw_passwd)); 696 free(old); 697 } 698 return (save); 699} 700 701static int login_attempts; /* number of failed login attempts */ 702static int askpasswd; /* had user command, ask for passwd */ 703static char curname[MAXLOGNAME]; /* current USER name */ 704 705/* 706 * USER command. 707 * Sets global passwd pointer pw if named account exists and is acceptable; 708 * sets askpasswd if a PASS command is expected. If logged in previously, 709 * need to reset state. If name is "ftp" or "anonymous", the name is not in 710 * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return. 711 * If account doesn't exist, ask for passwd anyway. Otherwise, check user 712 * requesting login privileges. Disallow anyone who does not have a standard 713 * shell as returned by getusershell(). Disallow anyone mentioned in the file 714 * _PATH_FTPUSERS to allow people such as root and uucp to be avoided. 715 */ 716void 717user(char *name) 718{ 719 char *cp, *shell, *style, *host; 720 char *class = NULL; 721 722 if (logged_in) 723 end_login(); 724 725 /* Close session from previous user if there was one. */ 726 if (as) { 727 auth_close(as); 728 as = NULL; 729 } 730 if (lc) { 731 login_close(lc); 732 lc = NULL; 733 } 734 735 if ((style = strchr(name, ':')) != NULL) 736 *style++ = 0; 737 738 guest = 0; 739 host = multihome ? dhostname : hostname; 740 if (anon_ok && 741 (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0)) { 742 if (checkuser(_PATH_FTPUSERS, "ftp") || 743 checkuser(_PATH_FTPUSERS, "anonymous")) 744 reply(530, "User %s access denied.", name); 745 else if ((pw = sgetpwnam("ftp", NULL)) != NULL) { 746 guest = 1; 747 askpasswd = 1; 748 lc = login_getclass(pw->pw_class); 749 if ((as = auth_open()) == NULL || 750 auth_setpwd(as, pw) != 0 || 751 auth_setoption(as, "FTPD_HOST", host) < 0) { 752 if (as) { 753 auth_close(as); 754 as = NULL; 755 } 756 login_close(lc); 757 lc = NULL; 758 reply(421, "Local resource failure"); 759 return; 760 } 761 reply(331, 762 "Guest login ok, send your email address as password."); 763 } else 764 reply(530, "User %s unknown.", name); 765 if (!askpasswd && logging) 766 syslog(LOG_NOTICE, 767 "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost); 768 return; 769 } 770 771 shell = _PATH_BSHELL; 772 if ((pw = sgetpwnam(name, NULL))) { 773 class = pw->pw_class; 774 if (pw->pw_shell != NULL && *pw->pw_shell != '\0') 775 shell = pw->pw_shell; 776 while ((cp = getusershell()) != NULL) 777 if (strcmp(cp, shell) == 0) 778 break; 779 shell = cp; 780 endusershell(); 781 } 782 783 /* Get login class; if invalid style treat like unknown user. */ 784 lc = login_getclass(class); 785 if (lc && (style = login_getstyle(lc, style, "auth-ftp")) == NULL) { 786 login_close(lc); 787 lc = NULL; 788 pw = NULL; 789 } 790 791 /* Do pre-authentication setup. */ 792 if (lc && ((as = auth_open()) == NULL || 793 (pw != NULL && auth_setpwd(as, pw) != 0) || 794 auth_setitem(as, AUTHV_STYLE, style) < 0 || 795 auth_setitem(as, AUTHV_NAME, name) < 0 || 796 auth_setitem(as, AUTHV_CLASS, class) < 0 || 797 auth_setoption(as, "login", "yes") < 0 || 798 auth_setoption(as, "notickets", "yes") < 0 || 799 auth_setoption(as, "FTPD_HOST", host) < 0)) { 800 if (as) { 801 auth_close(as); 802 as = NULL; 803 } 804 login_close(lc); 805 lc = NULL; 806 reply(421, "Local resource failure"); 807 return; 808 } 809 if (logging) 810 strlcpy(curname, name, sizeof(curname)); 811 812 dochroot = (lc && login_getcapbool(lc, "ftp-chroot", 0)) || 813 checkuser(_PATH_FTPCHROOT, name); 814 if (anon_only && !dochroot) { 815 reply(530, "Sorry, only anonymous ftp allowed."); 816 return; 817 } 818 if (pw) { 819 if ((!shell && !dochroot) || checkuser(_PATH_FTPUSERS, name)) { 820 reply(530, "User %s access denied.", name); 821 if (logging) 822 syslog(LOG_NOTICE, 823 "FTP LOGIN REFUSED FROM %s, %s", 824 remotehost, name); 825 pw = NULL; 826 return; 827 } 828 } 829 830 if (as != NULL && (cp = auth_challenge(as)) != NULL) 831 reply(331, "%s", cp); 832 else 833 reply(331, "Password required for %s.", name); 834 835 askpasswd = 1; 836 /* 837 * Delay before reading passwd after first failed 838 * attempt to slow down passwd-guessing programs. 839 */ 840 if (login_attempts) 841 sleep((unsigned) login_attempts); 842} 843 844/* 845 * Check if a user is in the file "fname" 846 */ 847static int 848checkuser(char *fname, char *name) 849{ 850 FILE *fp; 851 int found = 0; 852 char *p, line[BUFSIZ]; 853 854 if ((fp = fopen(fname, "r")) != NULL) { 855 while (fgets(line, sizeof(line), fp) != NULL) 856 if ((p = strchr(line, '\n')) != NULL) { 857 *p = '\0'; 858 if (line[0] == '#') 859 continue; 860 if (strcmp(line, name) == 0) { 861 found = 1; 862 break; 863 } 864 } 865 (void) fclose(fp); 866 } 867 return (found); 868} 869 870/* 871 * Terminate login as previous user, if any, resetting state; 872 * used when USER command is given or login fails. 873 */ 874static void 875end_login(void) 876{ 877 878 sigprocmask (SIG_BLOCK, &allsigs, NULL); 879 if (logged_in) { 880 ftpdlogwtmp(ttyline, "", ""); 881 if (doutmp) 882 ftpd_logout(utmp.ut_line); 883 } 884 reply(530, "Please reconnect to work as another user"); 885 exit(0); 886} 887 888void 889pass(char *passwd) 890{ 891 int authok, flags; 892 FILE *fp; 893 static char homedir[MAXPATHLEN]; 894 char *motd, *dir, rootdir[MAXPATHLEN]; 895 size_t sz_pw_dir; 896 897 if (logged_in || askpasswd == 0) { 898 reply(503, "Login with USER first."); 899 return; 900 } 901 askpasswd = 0; 902 if (!guest) { /* "ftp" is only account allowed no password */ 903 authok = 0; 904 if (pw == NULL || pw->pw_passwd[0] == '\0') { 905 useconds_t us; 906 907 /* Sleep between 1 and 3 seconds to emulate a crypt. */ 908 us = arc4random() % 3000000; 909 usleep(us); 910 if (as != NULL) { 911 auth_close(as); 912 as = NULL; 913 } 914 } else { 915 authok = auth_userresponse(as, passwd, 0); 916 as = NULL; 917 } 918 if (authok == 0) { 919 reply(530, "Login incorrect."); 920 if (logging) 921 syslog(LOG_NOTICE, 922 "FTP LOGIN FAILED FROM %s, %s", 923 remotehost, curname); 924 pw = NULL; 925 if (login_attempts++ >= 5) { 926 syslog(LOG_NOTICE, 927 "repeated login failures from %s", 928 remotehost); 929 exit(0); 930 } 931 return; 932 } 933 } else if (lc != NULL) { 934 /* Save anonymous' password. */ 935 if (guestpw != NULL) 936 free(guestpw); 937 guestpw = strdup(passwd); 938 if (guestpw == NULL) 939 fatal("Out of memory."); 940 941 authok = auth_approval(as, lc, pw->pw_name, "ftp"); 942 auth_close(as); 943 as = NULL; 944 if (authok == 0) { 945 syslog(LOG_INFO|LOG_AUTH, 946 "FTP LOGIN FAILED (HOST) as %s: approval failure.", 947 pw->pw_name); 948 reply(530, "Approval failure."); 949 exit(0); 950 } 951 } else { 952 syslog(LOG_INFO|LOG_AUTH, 953 "FTP LOGIN CLASS %s MISSING for %s: approval failure.", 954 pw->pw_class, pw->pw_name); 955 reply(530, "Permission denied."); 956 exit(0); 957 } 958 login_attempts = 0; /* this time successful */ 959 /* set umask via setusercontext() unless -u flag was given. */ 960 flags = LOGIN_SETGROUP|LOGIN_SETPRIORITY|LOGIN_SETRESOURCES; 961 if (umaskchange) 962 flags |= LOGIN_SETUMASK; 963 else 964 (void) umask(defumask); 965 if (setusercontext(lc, pw, (uid_t)0, flags) != 0) { 966 perror_reply(451, "Local resource failure: setusercontext"); 967 syslog(LOG_NOTICE, "setusercontext: %m"); 968 dologout(1); 969 /* NOTREACHED */ 970 } 971 972 /* open wtmp before chroot */ 973 ftpdlogwtmp(ttyline, pw->pw_name, remotehost); 974 975 /* open utmp before chroot */ 976 if (doutmp) { 977 memset((void *)&utmp, 0, sizeof(utmp)); 978 (void)time(&utmp.ut_time); 979 (void)strncpy(utmp.ut_name, pw->pw_name, sizeof(utmp.ut_name)); 980 (void)strncpy(utmp.ut_host, remotehost, sizeof(utmp.ut_host)); 981 (void)strncpy(utmp.ut_line, ttyline, sizeof(utmp.ut_line)); 982 ftpd_login(&utmp); 983 } 984 985 /* open stats file before chroot */ 986 if (guest && (stats == 1) && (statfd < 0)) 987 if ((statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND)) < 0) 988 stats = 0; 989 990 logged_in = 1; 991 992 if ((dir = login_getcapstr(lc, "ftp-dir", NULL, NULL))) { 993 char *newdir; 994 995 newdir = copy_dir(dir, pw); 996 if (newdir == NULL) { 997 perror_reply(421, "Local resource failure: malloc"); 998 dologout(1); 999 /* NOTREACHED */ 1000 } 1001 pw->pw_dir = newdir; 1002 pw = sgetpwnam(NULL, pw); 1003 free(dir); 1004 free(newdir); 1005 } 1006 1007 /* make sure pw->pw_dir is big enough to hold "/" */ 1008 sz_pw_dir = strlen(pw->pw_dir) + 1; 1009 if (sz_pw_dir < 2) { 1010 pw->pw_dir = "/"; 1011 pw = sgetpwnam(NULL, pw); 1012 sz_pw_dir = 2; 1013 } 1014 1015 if (guest || dochroot) { 1016 if (multihome && guest) { 1017 struct stat ts; 1018 1019 /* Compute root directory. */ 1020 snprintf(rootdir, sizeof(rootdir), "%s/%s", 1021 pw->pw_dir, dhostname); 1022 if (stat(rootdir, &ts) < 0) { 1023 snprintf(rootdir, sizeof(rootdir), "%s/%s", 1024 pw->pw_dir, hostname); 1025 } 1026 } else 1027 strlcpy(rootdir, pw->pw_dir, sizeof(rootdir)); 1028 } 1029 if (guest) { 1030 /* 1031 * We MUST do a chdir() after the chroot. Otherwise 1032 * the old current directory will be accessible as "." 1033 * outside the new root! 1034 */ 1035 if (chroot(rootdir) < 0 || chdir("/") < 0) { 1036 reply(550, "Can't set guest privileges."); 1037 goto bad; 1038 } 1039 strlcpy(pw->pw_dir, "/", sz_pw_dir); 1040 if (setenv("HOME", "/", 1) == -1) { 1041 reply(550, "Can't setup environment."); 1042 goto bad; 1043 } 1044 } else if (dochroot) { 1045 if (chroot(rootdir) < 0 || chdir("/") < 0) { 1046 reply(550, "Can't change root."); 1047 goto bad; 1048 } 1049 strlcpy(pw->pw_dir, "/", sz_pw_dir); 1050 if (setenv("HOME", "/", 1) == -1) { 1051 reply(550, "Can't setup environment."); 1052 goto bad; 1053 } 1054 } else if (chdir(pw->pw_dir) < 0) { 1055 if (chdir("/") < 0) { 1056 reply(530, "User %s: can't change directory to %s.", 1057 pw->pw_name, pw->pw_dir); 1058 goto bad; 1059 } else 1060 lreply(230, "No directory! Logging in with home=/"); 1061 } 1062 if (seteuid(pw->pw_uid) < 0) { 1063 reply(550, "Can't set uid."); 1064 goto bad; 1065 } 1066 sigprocmask(SIG_UNBLOCK, &allsigs, NULL); 1067 1068 /* 1069 * Set home directory so that use of ~ (tilde) works correctly. 1070 */ 1071 if (getcwd(homedir, MAXPATHLEN) != NULL) { 1072 if (setenv("HOME", homedir, 1) == -1) { 1073 reply(550, "Can't setup environment."); 1074 goto bad; 1075 } 1076 } 1077 1078 /* 1079 * Display a login message, if it exists. 1080 * N.B. reply(230,) must follow the message. 1081 */ 1082 motd = login_getcapstr(lc, "welcome", NULL, NULL); 1083 if ((fp = fopen(motd ? motd : _PATH_FTPLOGINMESG, "r")) != NULL) { 1084 char *cp, line[LINE_MAX]; 1085 1086 while (fgets(line, sizeof(line), fp) != NULL) { 1087 if ((cp = strchr(line, '\n')) != NULL) 1088 *cp = '\0'; 1089 lreply(230, "%s", line); 1090 } 1091 (void) fflush(stdout); 1092 (void) fclose(fp); 1093 } 1094 if (motd != NULL) 1095 free(motd); 1096 if (guest) { 1097 if (ident != NULL) 1098 free(ident); 1099 ident = strdup(passwd); 1100 if (ident == NULL) 1101 fatal("Ran out of memory."); 1102 reply(230, "Guest login ok, access restrictions apply."); 1103#ifdef HASSETPROCTITLE 1104 snprintf(proctitle, sizeof(proctitle), 1105 "%s: anonymous/%.*s", remotehost, 1106 (int)(sizeof(proctitle) - sizeof(remotehost) - 1107 sizeof(": anonymous/")), passwd); 1108 setproctitle("%s", proctitle); 1109#endif /* HASSETPROCTITLE */ 1110 if (logging) 1111 syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s", 1112 remotehost, passwd); 1113 } else { 1114 reply(230, "User %s logged in.", pw->pw_name); 1115#ifdef HASSETPROCTITLE 1116 snprintf(proctitle, sizeof(proctitle), 1117 "%s: %s", remotehost, pw->pw_name); 1118 setproctitle("%s", proctitle); 1119#endif /* HASSETPROCTITLE */ 1120 if (logging) 1121 syslog(LOG_INFO, "FTP LOGIN FROM %s as %s", 1122 remotehost, pw->pw_name); 1123 } 1124 login_close(lc); 1125 lc = NULL; 1126 return; 1127bad: 1128 /* Forget all about it... */ 1129 login_close(lc); 1130 lc = NULL; 1131 end_login(); 1132} 1133 1134void 1135retrieve(char *cmd, char *name) 1136{ 1137 FILE *fin, *dout; 1138 struct stat st; 1139 int (*closefunc)(FILE *); 1140 time_t start; 1141 1142 if (cmd == 0) { 1143 fin = fopen(name, "r"), closefunc = fclose; 1144 st.st_size = 0; 1145 } else { 1146 char line[BUFSIZ]; 1147 1148 (void) snprintf(line, sizeof(line), cmd, name); 1149 name = line; 1150 fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose; 1151 st.st_size = -1; 1152 st.st_blksize = BUFSIZ; 1153 } 1154 if (fin == NULL) { 1155 if (errno != 0) { 1156 perror_reply(550, name); 1157 if (cmd == 0) { 1158 LOGCMD("get", name); 1159 } 1160 } 1161 return; 1162 } 1163 byte_count = -1; 1164 if (cmd == 0 && (fstat(fileno(fin), &st) < 0 || !S_ISREG(st.st_mode))) { 1165 reply(550, "%s: not a plain file.", name); 1166 goto done; 1167 } 1168 if (restart_point) { 1169 if (type == TYPE_A) { 1170 off_t i, n; 1171 int c; 1172 1173 n = restart_point; 1174 i = 0; 1175 while (i++ < n) { 1176 if ((c=getc(fin)) == EOF) { 1177 perror_reply(550, name); 1178 goto done; 1179 } 1180 if (c == '\n') 1181 i++; 1182 } 1183 } else if (lseek(fileno(fin), restart_point, SEEK_SET) < 0) { 1184 perror_reply(550, name); 1185 goto done; 1186 } 1187 } 1188 dout = dataconn(name, st.st_size, "w"); 1189 if (dout == NULL) 1190 goto done; 1191 time(&start); 1192 send_data(fin, dout, st.st_blksize, st.st_size, 1193 (restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode))); 1194 if ((cmd == 0) && stats) 1195 logxfer(name, byte_count, start); 1196 (void) fclose(dout); 1197 data = -1; 1198done: 1199 if (pdata >= 0) 1200 (void) close(pdata); 1201 pdata = -1; 1202 if (cmd == 0) 1203 LOGBYTES("get", name, byte_count); 1204 (*closefunc)(fin); 1205} 1206 1207void 1208store(char *name, char *mode, int unique) 1209{ 1210 FILE *fout, *din; 1211 int (*closefunc)(FILE *); 1212 struct stat st; 1213 int fd; 1214 1215 if (restart_point && *mode != 'a') 1216 mode = "r+"; 1217 1218 if (unique && stat(name, &st) == 0) { 1219 char *nam; 1220 1221 fd = guniquefd(name, &nam); 1222 if (fd == -1) { 1223 LOGCMD(*mode == 'w' ? "put" : "append", name); 1224 return; 1225 } 1226 name = nam; 1227 fout = fdopen(fd, mode); 1228 } else 1229 fout = fopen(name, mode); 1230 1231 closefunc = fclose; 1232 if (fout == NULL) { 1233 perror_reply(553, name); 1234 LOGCMD(*mode == 'w' ? "put" : "append", name); 1235 return; 1236 } 1237 byte_count = -1; 1238 if (restart_point) { 1239 if (type == TYPE_A) { 1240 off_t i, n; 1241 int c; 1242 1243 n = restart_point; 1244 i = 0; 1245 while (i++ < n) { 1246 if ((c=getc(fout)) == EOF) { 1247 perror_reply(550, name); 1248 goto done; 1249 } 1250 if (c == '\n') 1251 i++; 1252 } 1253 /* 1254 * We must do this seek to "current" position 1255 * because we are changing from reading to 1256 * writing. 1257 */ 1258 if (fseek(fout, 0L, SEEK_CUR) < 0) { 1259 perror_reply(550, name); 1260 goto done; 1261 } 1262 } else if (lseek(fileno(fout), restart_point, SEEK_SET) < 0) { 1263 perror_reply(550, name); 1264 goto done; 1265 } 1266 } 1267 din = dataconn(name, (off_t)-1, "r"); 1268 if (din == NULL) 1269 goto done; 1270 if (receive_data(din, fout) == 0) { 1271 if (unique) 1272 reply(226, "Transfer complete (unique file name:%s).", 1273 name); 1274 else 1275 reply(226, "Transfer complete."); 1276 } 1277 (void) fclose(din); 1278 data = -1; 1279 pdata = -1; 1280done: 1281 LOGBYTES(*mode == 'w' ? "put" : "append", name, byte_count); 1282 (*closefunc)(fout); 1283} 1284 1285static FILE * 1286getdatasock(char *mode) 1287{ 1288 int on = 1, s, t, tries; 1289 1290 if (data >= 0) 1291 return (fdopen(data, mode)); 1292 sigprocmask (SIG_BLOCK, &allsigs, NULL); 1293 (void) seteuid(0); 1294 s = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 1295 (void) seteuid((uid_t)pw->pw_uid); 1296 if (s < 0) 1297 goto bad; 1298 if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, 1299 (char *) &on, sizeof(on)) < 0) 1300 goto bad; 1301 /* anchor socket to avoid multi-homing problems */ 1302 data_source = ctrl_addr; 1303 data_source.su_port = htons(20); /* ftp-data port */ 1304 (void) seteuid(0); 1305 for (tries = 1; ; tries++) { 1306 if (bind(s, (struct sockaddr *)&data_source, 1307 data_source.su_len) >= 0) 1308 break; 1309 if (errno != EADDRINUSE || tries > 10) { 1310 (void) seteuid(pw->pw_uid); 1311 goto bad; 1312 } 1313 sleep(tries); 1314 } 1315 (void) seteuid((uid_t)pw->pw_uid); 1316 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1317 1318#ifdef IP_TOS 1319 if (ctrl_addr.su_family == AF_INET) { 1320 on = IPTOS_THROUGHPUT; 1321 if (setsockopt(s, IPPROTO_IP, IP_TOS, (char *)&on, 1322 sizeof(int)) < 0) 1323 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 1324 } 1325#endif 1326#ifdef TCP_NOPUSH 1327 /* 1328 * Turn off push flag to keep sender TCP from sending short packets 1329 * at the boundaries of each write(). Should probably do a SO_SNDBUF 1330 * to set the send buffer size as well, but that may not be desirable 1331 * in heavy-load situations. 1332 */ 1333 on = 1; 1334 if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, (char *)&on, sizeof(on)) < 0) 1335 syslog(LOG_WARNING, "setsockopt (TCP_NOPUSH): %m"); 1336#endif 1337#ifdef SO_SNDBUF 1338 on = 65536; 1339 if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, (char *)&on, sizeof(on)) < 0) 1340 syslog(LOG_WARNING, "setsockopt (SO_SNDBUF): %m"); 1341#endif 1342 1343 return (fdopen(s, mode)); 1344bad: 1345 /* Return the real value of errno (close may change it) */ 1346 t = errno; 1347 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1348 (void) close(s); 1349 errno = t; 1350 return (NULL); 1351} 1352 1353static FILE * 1354dataconn(char *name, off_t size, char *mode) 1355{ 1356 char sizebuf[32]; 1357 FILE *file; 1358 int retry = 0; 1359 in_port_t *p; 1360 u_char *fa, *ha; 1361 int alen; 1362 1363 file_size = size; 1364 byte_count = 0; 1365 if (size != (off_t) -1) { 1366 (void) snprintf(sizebuf, sizeof(sizebuf), " (%qd bytes)", 1367 size); 1368 } else 1369 sizebuf[0] = '\0'; 1370 if (pdata >= 0) { 1371 union sockunion from; 1372 int s; 1373 socklen_t fromlen = sizeof(from); 1374 1375 (void) alarm ((unsigned) timeout); 1376 s = accept(pdata, (struct sockaddr *)&from, &fromlen); 1377 (void) alarm (0); 1378 if (s < 0) { 1379 reply(425, "Can't open data connection."); 1380 (void) close(pdata); 1381 pdata = -1; 1382 return (NULL); 1383 } 1384 switch (from.su_family) { 1385 case AF_INET: 1386 p = (in_port_t *)&from.su_sin.sin_port; 1387 fa = (u_char *)&from.su_sin.sin_addr; 1388 ha = (u_char *)&his_addr.su_sin.sin_addr; 1389 alen = sizeof(struct in_addr); 1390 break; 1391 case AF_INET6: 1392 p = (in_port_t *)&from.su_sin6.sin6_port; 1393 fa = (u_char *)&from.su_sin6.sin6_addr; 1394 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1395 alen = sizeof(struct in6_addr); 1396 break; 1397 default: 1398 perror_reply(425, "Can't build data connection"); 1399 (void) close(pdata); 1400 (void) close(s); 1401 pdata = -1; 1402 return (NULL); 1403 } 1404 if (from.su_family != his_addr.su_family || 1405 ntohs(*p) < IPPORT_RESERVED) { 1406 perror_reply(425, "Can't build data connection"); 1407 (void) close(pdata); 1408 (void) close(s); 1409 pdata = -1; 1410 return (NULL); 1411 } 1412 if (portcheck && memcmp(fa, ha, alen) != 0) { 1413 perror_reply(435, "Can't build data connection"); 1414 (void) close(pdata); 1415 (void) close(s); 1416 pdata = -1; 1417 return (NULL); 1418 } 1419 (void) close(pdata); 1420 pdata = s; 1421 reply(150, "Opening %s mode data connection for '%s'%s.", 1422 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1423 return (fdopen(pdata, mode)); 1424 } 1425 if (data >= 0) { 1426 reply(125, "Using existing data connection for '%s'%s.", 1427 name, sizebuf); 1428 usedefault = 1; 1429 return (fdopen(data, mode)); 1430 } 1431 if (usedefault) 1432 data_dest = his_addr; 1433 usedefault = 1; 1434 do { 1435 file = getdatasock(mode); 1436 if (file == NULL) { 1437 char hbuf[MAXHOSTNAMELEN], pbuf[10]; 1438 1439 getnameinfo((struct sockaddr *)&data_source, 1440 data_source.su_len, hbuf, sizeof(hbuf), pbuf, 1441 sizeof(pbuf), NI_NUMERICHOST | NI_NUMERICSERV); 1442 reply(425, "Can't create data socket (%s,%s): %s.", 1443 hbuf, pbuf, strerror(errno)); 1444 return (NULL); 1445 } 1446 1447 /* 1448 * attempt to connect to reserved port on client machine; 1449 * this looks like an attack 1450 */ 1451 switch (data_dest.su_family) { 1452 case AF_INET: 1453 p = (in_port_t *)&data_dest.su_sin.sin_port; 1454 fa = (u_char *)&data_dest.su_sin.sin_addr; 1455 ha = (u_char *)&his_addr.su_sin.sin_addr; 1456 alen = sizeof(struct in_addr); 1457 break; 1458 case AF_INET6: 1459 p = (in_port_t *)&data_dest.su_sin6.sin6_port; 1460 fa = (u_char *)&data_dest.su_sin6.sin6_addr; 1461 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1462 alen = sizeof(struct in6_addr); 1463 break; 1464 default: 1465 perror_reply(425, "Can't build data connection"); 1466 (void) fclose(file); 1467 pdata = -1; 1468 return (NULL); 1469 } 1470 if (data_dest.su_family != his_addr.su_family || 1471 ntohs(*p) < IPPORT_RESERVED || ntohs(*p) == 2049) { /* XXX */ 1472 perror_reply(425, "Can't build data connection"); 1473 (void) fclose(file); 1474 return NULL; 1475 } 1476 if (portcheck && memcmp(fa, ha, alen) != 0) { 1477 perror_reply(435, "Can't build data connection"); 1478 (void) fclose(file); 1479 return NULL; 1480 } 1481 1482 if (connect(fileno(file), (struct sockaddr *)&data_dest, 1483 data_dest.su_len) == 0) { 1484 reply(150, "Opening %s mode data connection for '%s'%s.", 1485 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1486 data = fileno(file); 1487 return (file); 1488 } 1489 if (errno != EADDRINUSE) 1490 break; 1491 (void) fclose(file); 1492 sleep((unsigned) swaitint); 1493 retry += swaitint; 1494 } while (retry <= swaitmax); 1495 perror_reply(425, "Can't build data connection"); 1496 (void) fclose(file); 1497 return (NULL); 1498} 1499 1500/* 1501 * Tranfer the contents of "instr" to "outstr" peer using the appropriate 1502 * encapsulation of the data subject to Mode, Structure, and Type. 1503 * 1504 * NB: Form isn't handled. 1505 */ 1506static int 1507send_data(FILE *instr, FILE *outstr, off_t blksize, off_t filesize, int isreg) 1508{ 1509 int c, cnt, filefd, netfd; 1510 char *buf, *bp; 1511 size_t len; 1512 1513 transflag++; 1514 switch (type) { 1515 1516 case TYPE_A: 1517 while ((c = getc(instr)) != EOF) { 1518 if (recvurg) 1519 goto got_oob; 1520 byte_count++; 1521 if (c == '\n') { 1522 if (ferror(outstr)) 1523 goto data_err; 1524 (void) putc('\r', outstr); 1525 } 1526 (void) putc(c, outstr); 1527 } 1528 fflush(outstr); 1529 transflag = 0; 1530 if (ferror(instr)) 1531 goto file_err; 1532 if (ferror(outstr)) 1533 goto data_err; 1534 reply(226, "Transfer complete."); 1535 return(0); 1536 1537 case TYPE_I: 1538 case TYPE_L: 1539 /* 1540 * isreg is only set if we are not doing restart and we 1541 * are sending a regular file 1542 */ 1543 netfd = fileno(outstr); 1544 filefd = fileno(instr); 1545 1546 if (isreg && filesize < (off_t)16 * 1024 * 1024) { 1547 buf = mmap(0, filesize, PROT_READ, MAP_SHARED, filefd, 1548 (off_t)0); 1549 if (buf == MAP_FAILED) { 1550 syslog(LOG_WARNING, "mmap(%lu): %m", 1551 (unsigned long)filesize); 1552 goto oldway; 1553 } 1554 bp = buf; 1555 len = filesize; 1556 do { 1557 cnt = write(netfd, bp, len); 1558 if (recvurg) { 1559 munmap(buf, (size_t)filesize); 1560 goto got_oob; 1561 } 1562 len -= cnt; 1563 bp += cnt; 1564 if (cnt > 0) byte_count += cnt; 1565 } while(cnt > 0 && len > 0); 1566 1567 transflag = 0; 1568 munmap(buf, (size_t)filesize); 1569 if (cnt < 0) 1570 goto data_err; 1571 reply(226, "Transfer complete."); 1572 return(0); 1573 } 1574 1575oldway: 1576 if ((buf = malloc((u_int)blksize)) == NULL) { 1577 transflag = 0; 1578 perror_reply(451, "Local resource failure: malloc"); 1579 return(-1); 1580 } 1581 1582 while ((cnt = read(filefd, buf, (u_int)blksize)) > 0 && 1583 write(netfd, buf, cnt) == cnt) 1584 byte_count += cnt; 1585 transflag = 0; 1586 (void)free(buf); 1587 if (cnt != 0) { 1588 if (cnt < 0) 1589 goto file_err; 1590 goto data_err; 1591 } 1592 reply(226, "Transfer complete."); 1593 return(0); 1594 default: 1595 transflag = 0; 1596 reply(550, "Unimplemented TYPE %d in send_data", type); 1597 return(-1); 1598 } 1599 1600data_err: 1601 transflag = 0; 1602 perror_reply(426, "Data connection"); 1603 return(-1); 1604 1605file_err: 1606 transflag = 0; 1607 perror_reply(551, "Error on input file"); 1608 return(-1); 1609 1610got_oob: 1611 myoob(); 1612 recvurg = 0; 1613 transflag = 0; 1614 return(-1); 1615} 1616 1617/* 1618 * Transfer data from peer to "outstr" using the appropriate encapulation of 1619 * the data subject to Mode, Structure, and Type. 1620 * 1621 * N.B.: Form isn't handled. 1622 */ 1623static int 1624receive_data(FILE *instr, FILE *outstr) 1625{ 1626 int c; 1627 int cnt; 1628 char buf[BUFSIZ]; 1629 struct sigaction sa, sa_saved; 1630 volatile int bare_lfs = 0; 1631 1632 transflag++; 1633 switch (type) { 1634 1635 case TYPE_I: 1636 case TYPE_L: 1637 memset(&sa, 0, sizeof(sa)); 1638 sigfillset(&sa.sa_mask); 1639 sa.sa_flags = SA_RESTART; 1640 sa.sa_handler = lostconn; 1641 (void) sigaction(SIGALRM, &sa, &sa_saved); 1642 do { 1643 (void) alarm ((unsigned) timeout); 1644 cnt = read(fileno(instr), buf, sizeof(buf)); 1645 (void) alarm (0); 1646 if (recvurg) 1647 goto got_oob; 1648 1649 if (cnt > 0) { 1650 if (write(fileno(outstr), buf, cnt) != cnt) 1651 goto file_err; 1652 byte_count += cnt; 1653 } 1654 } while (cnt > 0); 1655 (void) sigaction(SIGALRM, &sa_saved, NULL); 1656 if (cnt < 0) 1657 goto data_err; 1658 transflag = 0; 1659 return (0); 1660 1661 case TYPE_E: 1662 reply(553, "TYPE E not implemented."); 1663 transflag = 0; 1664 return (-1); 1665 1666 case TYPE_A: 1667 while ((c = getc(instr)) != EOF) { 1668 if (recvurg) 1669 goto got_oob; 1670 byte_count++; 1671 if (c == '\n') 1672 bare_lfs++; 1673 while (c == '\r') { 1674 if (ferror(outstr)) 1675 goto data_err; 1676 if ((c = getc(instr)) != '\n') { 1677 (void) putc ('\r', outstr); 1678 if (c == '\0' || c == EOF) 1679 goto contin2; 1680 } 1681 } 1682 (void) putc(c, outstr); 1683 contin2: ; 1684 } 1685 fflush(outstr); 1686 if (ferror(instr)) 1687 goto data_err; 1688 if (ferror(outstr)) 1689 goto file_err; 1690 transflag = 0; 1691 if (bare_lfs) { 1692 lreply(226, 1693 "WARNING! %d bare linefeeds received in ASCII mode", 1694 bare_lfs); 1695 printf(" File may not have transferred correctly.\r\n"); 1696 } 1697 return (0); 1698 default: 1699 reply(550, "Unimplemented TYPE %d in receive_data", type); 1700 transflag = 0; 1701 return (-1); 1702 } 1703 1704data_err: 1705 transflag = 0; 1706 perror_reply(426, "Data Connection"); 1707 return (-1); 1708 1709file_err: 1710 transflag = 0; 1711 perror_reply(452, "Error writing file"); 1712 return (-1); 1713 1714got_oob: 1715 myoob(); 1716 recvurg = 0; 1717 transflag = 0; 1718 return (-1); 1719} 1720 1721void 1722statfilecmd(char *filename) 1723{ 1724 FILE *fin; 1725 int c; 1726 int atstart; 1727 char line[LINE_MAX]; 1728 1729 (void)snprintf(line, sizeof(line), "/bin/ls -lgA %s", filename); 1730 fin = ftpd_popen(line, "r"); 1731 lreply(211, "status of %s:", filename); 1732 atstart = 1; 1733 while ((c = getc(fin)) != EOF) { 1734 if (c == '\n') { 1735 if (ferror(stdout)){ 1736 perror_reply(421, "control connection"); 1737 (void) ftpd_pclose(fin); 1738 dologout(1); 1739 /* NOTREACHED */ 1740 } 1741 if (ferror(fin)) { 1742 perror_reply(551, filename); 1743 (void) ftpd_pclose(fin); 1744 return; 1745 } 1746 (void) putc('\r', stdout); 1747 } 1748 if (atstart && isdigit(c)) 1749 (void) putc(' ', stdout); 1750 (void) putc(c, stdout); 1751 atstart = (c == '\n'); 1752 } 1753 (void) ftpd_pclose(fin); 1754 reply(211, "End of Status"); 1755} 1756 1757void 1758statcmd(void) 1759{ 1760 union sockunion *su; 1761 u_char *a, *p; 1762 char hbuf[MAXHOSTNAMELEN]; 1763 int ispassive; 1764 1765 lreply(211, "%s FTP server status:", hostname); 1766 printf(" %s\r\n", version); 1767 getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len, 1768 hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST); 1769 printf(" Connected to %s", remotehost); 1770 if (strcmp(remotehost, hbuf) != 0) 1771 printf(" (%s)", hbuf); 1772 printf("\r\n"); 1773 if (logged_in) { 1774 if (guest) 1775 printf(" Logged in anonymously\r\n"); 1776 else 1777 printf(" Logged in as %s\r\n", pw->pw_name); 1778 } else if (askpasswd) 1779 printf(" Waiting for password\r\n"); 1780 else 1781 printf(" Waiting for user name\r\n"); 1782 printf(" TYPE: %s", typenames[type]); 1783 if (type == TYPE_A || type == TYPE_E) 1784 printf(", FORM: %s", formnames[form]); 1785 if (type == TYPE_L) 1786#if NBBY == 8 1787 printf(" %d", NBBY); 1788#else 1789 printf(" %d", bytesize); /* need definition! */ 1790#endif 1791 printf("; STRUcture: %s; transfer MODE: %s\r\n", 1792 strunames[stru], modenames[mode]); 1793 ispassive = 0; 1794 if (data != -1) 1795 printf(" Data connection open\r\n"); 1796 else if (pdata != -1) { 1797 printf(" in Passive mode\r\n"); 1798 su = (union sockunion *)&pasv_addr; 1799 ispassive++; 1800 goto printaddr; 1801 } else if (usedefault == 0) { 1802 su = (union sockunion *)&data_dest; 1803printaddr: 1804 /* PASV/PORT */ 1805 if (su->su_family == AF_INET) { 1806 if (ispassive) 1807 printf("211- PASV "); 1808 else 1809 printf("211- PORT "); 1810 a = (u_char *) &su->su_sin.sin_addr; 1811 p = (u_char *) &su->su_sin.sin_port; 1812 printf("(%u,%u,%u,%u,%u,%u)\r\n", 1813 a[0], a[1], a[2], a[3], 1814 p[0], p[1]); 1815 } 1816 1817 /* LPSV/LPRT */ 1818 { 1819 int alen, af, i; 1820 1821 alen = 0; 1822 switch (su->su_family) { 1823 case AF_INET: 1824 a = (u_char *) &su->su_sin.sin_addr; 1825 p = (u_char *) &su->su_sin.sin_port; 1826 alen = sizeof(su->su_sin.sin_addr); 1827 af = 4; 1828 break; 1829 case AF_INET6: 1830 a = (u_char *) &su->su_sin6.sin6_addr; 1831 p = (u_char *) &su->su_sin6.sin6_port; 1832 alen = sizeof(su->su_sin6.sin6_addr); 1833 af = 6; 1834 break; 1835 default: 1836 af = 0; 1837 break; 1838 } 1839 if (af) { 1840 if (ispassive) 1841 printf("211- LPSV "); 1842 else 1843 printf("211- LPRT "); 1844 printf("(%u,%u", af, alen); 1845 for (i = 0; i < alen; i++) 1846 printf(",%u", a[i]); 1847 printf(",%u,%u,%u)\r\n", 2, p[0], p[1]); 1848 } 1849 } 1850 1851 /* EPRT/EPSV */ 1852 { 1853 u_char af; 1854 1855 switch (su->su_family) { 1856 case AF_INET: 1857 af = 1; 1858 break; 1859 case AF_INET6: 1860 af = 2; 1861 break; 1862 default: 1863 af = 0; 1864 break; 1865 } 1866 if (af) { 1867 char hbuf[MAXHOSTNAMELEN], pbuf[10]; 1868 union sockunion tmp = *su; 1869 1870 if (tmp.su_family == AF_INET6) 1871 tmp.su_sin6.sin6_scope_id = 0; 1872 if (getnameinfo((struct sockaddr *)&tmp, tmp.su_len, 1873 hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), 1874 NI_NUMERICHOST | NI_NUMERICSERV) == 0) { 1875 if (ispassive) 1876 printf("211- EPSV "); 1877 else 1878 printf("211- EPRT "); 1879 printf("(|%u|%s|%s|)\r\n", 1880 af, hbuf, pbuf); 1881 } 1882 } 1883 } 1884 } else 1885 printf(" No data connection\r\n"); 1886 reply(211, "End of status"); 1887} 1888 1889void 1890fatal(char *s) 1891{ 1892 1893 reply(451, "Error in server: %s", s); 1894 reply(221, "Closing connection due to server error."); 1895 dologout(0); 1896 /* NOTREACHED */ 1897} 1898 1899void 1900reply(int n, const char *fmt, ...) 1901{ 1902 char *buf, *p, *next; 1903 int rval; 1904 va_list ap; 1905 1906 va_start(ap, fmt); 1907 rval = vasprintf(&buf, fmt, ap); 1908 va_end(ap); 1909 if (rval == -1 || buf == NULL) { 1910 printf("412 Local resource failure: malloc\r\n"); 1911 fflush(stdout); 1912 dologout(1); 1913 } 1914 next = buf; 1915 while ((p = strsep(&next, "\n\r"))) { 1916 printf("%d%s %s\r\n", n, (next != '\0') ? "-" : "", p); 1917 if (debug) 1918 syslog(LOG_DEBUG, "<--- %d%s %s", n, 1919 (next != '\0') ? "-" : "", p); 1920 } 1921 (void)fflush(stdout); 1922 free(buf); 1923} 1924 1925void 1926lreply(int n, const char *fmt, ...) 1927{ 1928 va_list ap; 1929 1930 va_start(ap, fmt); 1931 (void)printf("%d- ", n); 1932 (void)vprintf(fmt, ap); 1933 va_end(ap); 1934 (void)printf("\r\n"); 1935 (void)fflush(stdout); 1936 if (debug) { 1937 va_start(ap, fmt); 1938 syslog(LOG_DEBUG, "<--- %d- ", n); 1939 vsyslog(LOG_DEBUG, fmt, ap); 1940 va_end(ap); 1941 } 1942} 1943 1944static void 1945ack(char *s) 1946{ 1947 1948 reply(250, "%s command successful.", s); 1949} 1950 1951void 1952nack(char *s) 1953{ 1954 1955 reply(502, "%s command not implemented.", s); 1956} 1957 1958/* ARGSUSED */ 1959void 1960yyerror(char *s) 1961{ 1962 char *cp; 1963 1964 if ((cp = strchr(cbuf,'\n'))) 1965 *cp = '\0'; 1966 reply(500, "'%s': command not understood.", cbuf); 1967} 1968 1969void 1970delete(char *name) 1971{ 1972 struct stat st; 1973 1974 LOGCMD("delete", name); 1975 if (stat(name, &st) < 0) { 1976 perror_reply(550, name); 1977 return; 1978 } 1979 if ((st.st_mode&S_IFMT) == S_IFDIR) { 1980 if (rmdir(name) < 0) { 1981 perror_reply(550, name); 1982 return; 1983 } 1984 goto done; 1985 } 1986 if (unlink(name) < 0) { 1987 perror_reply(550, name); 1988 return; 1989 } 1990done: 1991 ack("DELE"); 1992} 1993 1994void 1995cwd(char *path) 1996{ 1997 FILE *message; 1998 1999 if (chdir(path) < 0) 2000 perror_reply(550, path); 2001 else { 2002 if ((message = fopen(_PATH_CWDMESG, "r")) != NULL) { 2003 char *cp, line[LINE_MAX]; 2004 2005 while (fgets(line, sizeof(line), message) != NULL) { 2006 if ((cp = strchr(line, '\n')) != NULL) 2007 *cp = '\0'; 2008 lreply(250, "%s", line); 2009 } 2010 (void) fflush(stdout); 2011 (void) fclose(message); 2012 } 2013 ack("CWD"); 2014 } 2015} 2016 2017void 2018replydirname(const char *name, const char *message) 2019{ 2020 char *p, *ep; 2021 char npath[MAXPATHLEN * 2]; 2022 2023 p = npath; 2024 ep = &npath[sizeof(npath) - 1]; 2025 while (*name) { 2026 if (*name == '"') { 2027 if (ep - p < 2) 2028 break; 2029 *p++ = *name++; 2030 *p++ = '"'; 2031 } else { 2032 if (ep - p < 1) 2033 break; 2034 *p++ = *name++; 2035 } 2036 } 2037 *p = '\0'; 2038 reply(257, "\"%s\" %s", npath, message); 2039} 2040 2041void 2042makedir(char *name) 2043{ 2044 2045 LOGCMD("mkdir", name); 2046 if (mkdir(name, 0777) < 0) 2047 perror_reply(550, name); 2048 else 2049 replydirname(name, "directory created."); 2050} 2051 2052void 2053removedir(char *name) 2054{ 2055 2056 LOGCMD("rmdir", name); 2057 if (rmdir(name) < 0) 2058 perror_reply(550, name); 2059 else 2060 ack("RMD"); 2061} 2062 2063void 2064pwd(void) 2065{ 2066 char path[MAXPATHLEN]; 2067 2068 if (getcwd(path, sizeof(path)) == NULL) 2069 perror_reply(550, "Can't get current directory"); 2070 else 2071 replydirname(path, "is current directory."); 2072} 2073 2074char * 2075renamefrom(char *name) 2076{ 2077 struct stat st; 2078 2079 if (stat(name, &st) < 0) { 2080 perror_reply(550, name); 2081 return ((char *)0); 2082 } 2083 reply(350, "File exists, ready for destination name"); 2084 return (name); 2085} 2086 2087void 2088renamecmd(char *from, char *to) 2089{ 2090 2091 LOGCMD2("rename", from, to); 2092 if (rename(from, to) < 0) 2093 perror_reply(550, "rename"); 2094 else 2095 ack("RNTO"); 2096} 2097 2098static void 2099dolog(struct sockaddr *sa) 2100{ 2101 char hbuf[sizeof(remotehost)]; 2102 2103 getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), NULL, 0, 0); 2104 (void) strlcpy(remotehost, hbuf, sizeof(remotehost)); 2105 2106#ifdef HASSETPROCTITLE 2107 snprintf(proctitle, sizeof(proctitle), "%s: connected", remotehost); 2108 setproctitle("%s", proctitle); 2109#endif /* HASSETPROCTITLE */ 2110 2111 if (logging) 2112 syslog(LOG_INFO, "connection from %s", remotehost); 2113} 2114 2115/* 2116 * Record logout in wtmp file and exit with supplied status. 2117 * NOTE: because this is called from signal handlers it cannot 2118 * use stdio (or call other functions that use stdio). 2119 */ 2120void 2121dologout(int status) 2122{ 2123 2124 transflag = 0; 2125 2126 if (logged_in) { 2127 sigprocmask(SIG_BLOCK, &allsigs, NULL); 2128 ftpdlogwtmp(ttyline, "", ""); 2129 if (doutmp) 2130 ftpd_logout(utmp.ut_line); 2131 } 2132 /* beware of flushing buffers after a SIGPIPE */ 2133 _exit(status); 2134} 2135 2136static void 2137sigurg(int signo) 2138{ 2139 2140 recvurg = 1; 2141} 2142 2143static void 2144myoob(void) 2145{ 2146 char *cp; 2147 2148 /* only process if transfer occurring */ 2149 if (!transflag) 2150 return; 2151 cp = tmpline; 2152 if (getline(cp, 7, stdin) == NULL) { 2153 reply(221, "You could at least say goodbye."); 2154 dologout(0); 2155 } 2156 upper(cp); 2157 if (strcmp(cp, "ABOR\r\n") == 0) { 2158 tmpline[0] = '\0'; 2159 reply(426, "Transfer aborted. Data connection closed."); 2160 reply(226, "Abort successful"); 2161 } 2162 if (strcmp(cp, "STAT\r\n") == 0) { 2163 tmpline[0] = '\0'; 2164 if (file_size != (off_t) -1) 2165 reply(213, "Status: %qd of %qd bytes transferred", 2166 byte_count, file_size); 2167 else 2168 reply(213, "Status: %qd bytes transferred", byte_count); 2169 } 2170} 2171 2172/* 2173 * Note: a response of 425 is not mentioned as a possible response to 2174 * the PASV command in RFC959. However, it has been blessed as 2175 * a legitimate response by Jon Postel in a telephone conversation 2176 * with Rick Adams on 25 Jan 89. 2177 */ 2178void 2179passive(void) 2180{ 2181 socklen_t len; 2182 int on; 2183 u_char *p, *a; 2184 2185 if (pw == NULL) { 2186 reply(530, "Please login with USER and PASS"); 2187 return; 2188 } 2189 if (pdata >= 0) 2190 close(pdata); 2191 /* 2192 * XXX 2193 * At this point, it would be nice to have an algorithm that 2194 * inserted a growing delay in an attack scenario. Such a thing 2195 * would look like continual passive sockets being opened, but 2196 * nothing serious being done with them. They're not used to 2197 * move data; the entire attempt is just to use tcp FIN_WAIT 2198 * resources. 2199 */ 2200 pdata = socket(AF_INET, SOCK_STREAM, 0); 2201 if (pdata < 0) { 2202 perror_reply(425, "Can't open passive connection"); 2203 return; 2204 } 2205 2206 on = IP_PORTRANGE_HIGH; 2207 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2208 (char *)&on, sizeof(on)) < 0) 2209 goto pasv_error; 2210 2211 pasv_addr = ctrl_addr; 2212 pasv_addr.su_sin.sin_port = 0; 2213 if (bind(pdata, (struct sockaddr *)&pasv_addr, 2214 pasv_addr.su_len) < 0) 2215 goto pasv_error; 2216 2217 len = sizeof(pasv_addr); 2218 if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0) 2219 goto pasv_error; 2220 if (listen(pdata, 1) < 0) 2221 goto pasv_error; 2222 a = (u_char *) &pasv_addr.su_sin.sin_addr; 2223 p = (u_char *) &pasv_addr.su_sin.sin_port; 2224 2225 reply(227, "Entering Passive Mode (%u,%u,%u,%u,%u,%u)", a[0], 2226 a[1], a[2], a[3], p[0], p[1]); 2227 return; 2228 2229pasv_error: 2230 (void) close(pdata); 2231 pdata = -1; 2232 perror_reply(425, "Can't open passive connection"); 2233 return; 2234} 2235 2236/* 2237 * convert protocol identifier to/from AF 2238 */ 2239int 2240lpsvproto2af(int proto) 2241{ 2242 2243 switch (proto) { 2244 case 4: return AF_INET; 2245#ifdef INET6 2246 case 6: return AF_INET6; 2247#endif 2248 default: return -1; 2249 } 2250} 2251 2252int 2253af2lpsvproto(int af) 2254{ 2255 2256 switch (af) { 2257 case AF_INET: return 4; 2258#ifdef INET6 2259 case AF_INET6: return 6; 2260#endif 2261 default: return -1; 2262 } 2263} 2264 2265int 2266epsvproto2af(int proto) 2267{ 2268 2269 switch (proto) { 2270 case 1: return AF_INET; 2271#ifdef INET6 2272 case 2: return AF_INET6; 2273#endif 2274 default: return -1; 2275 } 2276} 2277 2278int 2279af2epsvproto(int af) 2280{ 2281 2282 switch (af) { 2283 case AF_INET: return 1; 2284#ifdef INET6 2285 case AF_INET6: return 2; 2286#endif 2287 default: return -1; 2288 } 2289} 2290 2291/* 2292 * 228 Entering Long Passive Mode (af, hal, h1, h2, h3,..., pal, p1, p2...) 2293 * 229 Entering Extended Passive Mode (|||port|) 2294 */ 2295void 2296long_passive(char *cmd, int pf) 2297{ 2298 socklen_t len; 2299 int on; 2300 u_char *p, *a; 2301 2302 if (!logged_in) { 2303 syslog(LOG_NOTICE, "long passive but not logged in"); 2304 reply(503, "Login with USER first."); 2305 return; 2306 } 2307 2308 if (pf != PF_UNSPEC && ctrl_addr.su_family != pf) { 2309 /* 2310 * XXX 2311 * only EPRT/EPSV ready clients will understand this 2312 */ 2313 if (strcmp(cmd, "EPSV") != 0) 2314 reply(501, "Network protocol mismatch"); /*XXX*/ 2315 else 2316 epsv_protounsupp("Network protocol mismatch"); 2317 2318 return; 2319 } 2320 2321 if (pdata >= 0) 2322 close(pdata); 2323 /* 2324 * XXX 2325 * At this point, it would be nice to have an algorithm that 2326 * inserted a growing delay in an attack scenario. Such a thing 2327 * would look like continual passive sockets being opened, but 2328 * nothing serious being done with them. They not used to move 2329 * data; the entire attempt is just to use tcp FIN_WAIT 2330 * resources. 2331 */ 2332 pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 2333 if (pdata < 0) { 2334 perror_reply(425, "Can't open passive connection"); 2335 return; 2336 } 2337 2338 switch (ctrl_addr.su_family) { 2339 case AF_INET: 2340 on = IP_PORTRANGE_HIGH; 2341 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2342 (char *)&on, sizeof(on)) < 0) 2343 goto pasv_error; 2344 break; 2345 case AF_INET6: 2346 on = IPV6_PORTRANGE_HIGH; 2347 if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE, 2348 (char *)&on, sizeof(on)) < 0) 2349 goto pasv_error; 2350 break; 2351 } 2352 2353 pasv_addr = ctrl_addr; 2354 pasv_addr.su_port = 0; 2355 if (bind(pdata, (struct sockaddr *) &pasv_addr, pasv_addr.su_len) < 0) 2356 goto pasv_error; 2357 len = pasv_addr.su_len; 2358 if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0) 2359 goto pasv_error; 2360 if (listen(pdata, 1) < 0) 2361 goto pasv_error; 2362 p = (u_char *) &pasv_addr.su_port; 2363 2364 if (strcmp(cmd, "LPSV") == 0) { 2365 switch (pasv_addr.su_family) { 2366 case AF_INET: 2367 a = (u_char *) &pasv_addr.su_sin.sin_addr; 2368 reply(228, 2369 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2370 4, 4, a[0], a[1], a[2], a[3], 2, p[0], p[1]); 2371 return; 2372 case AF_INET6: 2373 a = (u_char *) &pasv_addr.su_sin6.sin6_addr; 2374 reply(228, 2375 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u," 2376 "%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2377 6, 16, a[0], a[1], a[2], a[3], a[4], 2378 a[5], a[6], a[7], a[8], a[9], a[10], 2379 a[11], a[12], a[13], a[14], a[15], 2380 2, p[0], p[1]); 2381 return; 2382 } 2383 } else if (strcmp(cmd, "EPSV") == 0) { 2384 switch (pasv_addr.su_family) { 2385 case AF_INET: 2386 case AF_INET6: 2387 reply(229, "Entering Extended Passive Mode (|||%u|)", 2388 ntohs(pasv_addr.su_port)); 2389 return; 2390 } 2391 } else { 2392 /* more proper error code? */ 2393 } 2394 2395 pasv_error: 2396 (void) close(pdata); 2397 pdata = -1; 2398 perror_reply(425, "Can't open passive connection"); 2399 return; 2400} 2401 2402/* 2403 * EPRT |proto|addr|port| 2404 */ 2405int 2406extended_port(const char *arg) 2407{ 2408 char *tmp = NULL; 2409 char *result[3]; 2410 char *p, *q; 2411 char delim; 2412 struct addrinfo hints; 2413 struct addrinfo *res = NULL; 2414 int i; 2415 unsigned long proto; 2416 2417 if (epsvall) { 2418 reply(501, "EPRT disallowed after EPSV ALL"); 2419 return -1; 2420 } 2421 2422 usedefault = 0; 2423 if (pdata >= 0) { 2424 (void) close(pdata); 2425 pdata = -1; 2426 } 2427 2428 tmp = strdup(arg); 2429 if (!tmp) { 2430 fatal("not enough core."); 2431 /*NOTREACHED*/ 2432 } 2433 p = tmp; 2434 delim = p[0]; 2435 p++; 2436 memset(result, 0, sizeof(result)); 2437 for (i = 0; i < 3; i++) { 2438 q = strchr(p, delim); 2439 if (!q || *q != delim) 2440 goto parsefail; 2441 *q++ = '\0'; 2442 result[i] = p; 2443 p = q; 2444 } 2445 2446 /* some more sanity check */ 2447 p = NULL; 2448 (void)strtoul(result[2], &p, 10); 2449 if (!*result[2] || *p) 2450 goto protounsupp; 2451 p = NULL; 2452 proto = strtoul(result[0], &p, 10); 2453 if (!*result[0] || *p) 2454 goto protounsupp; 2455 2456 memset(&hints, 0, sizeof(hints)); 2457 hints.ai_family = epsvproto2af((int)proto); 2458 if (hints.ai_family < 0) 2459 goto protounsupp; 2460 hints.ai_socktype = SOCK_STREAM; 2461 hints.ai_flags = AI_NUMERICHOST; /*no DNS*/ 2462 if (getaddrinfo(result[1], result[2], &hints, &res)) 2463 goto parsefail; 2464 if (res->ai_next) 2465 goto parsefail; 2466 if (sizeof(data_dest) < res->ai_addrlen) 2467 goto parsefail; 2468 memcpy(&data_dest, res->ai_addr, res->ai_addrlen); 2469 if (his_addr.su_family == AF_INET6 && 2470 data_dest.su_family == AF_INET6) { 2471 /* XXX more sanity checks! */ 2472 data_dest.su_sin6.sin6_scope_id = 2473 his_addr.su_sin6.sin6_scope_id; 2474 } 2475 if (pdata >= 0) { 2476 (void) close(pdata); 2477 pdata = -1; 2478 } 2479 reply(200, "EPRT command successful."); 2480 2481 if (tmp) 2482 free(tmp); 2483 if (res) 2484 freeaddrinfo(res); 2485 return 0; 2486 2487parsefail: 2488 reply(500, "Invalid argument, rejected."); 2489 usedefault = 1; 2490 if (tmp) 2491 free(tmp); 2492 if (res) 2493 freeaddrinfo(res); 2494 return -1; 2495 2496protounsupp: 2497 epsv_protounsupp("Protocol not supported"); 2498 usedefault = 1; 2499 if (tmp) 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(char *local, char **nam) 2531{ 2532 static char new[MAXPATHLEN]; 2533 struct stat st; 2534 int count, len, fd; 2535 char *cp; 2536 2537 cp = strrchr(local, '/'); 2538 if (cp) 2539 *cp = '\0'; 2540 if (stat(cp ? local : ".", &st) < 0) { 2541 perror_reply(553, cp ? local : "."); 2542 return (-1); 2543 } 2544 if (cp) 2545 *cp = '/'; 2546 len = strlcpy(new, local, sizeof(new)); 2547 if (len+2+1 >= sizeof(new)-1) 2548 return (-1); 2549 cp = new + len; 2550 *cp++ = '.'; 2551 for (count = 1; count < 100; count++) { 2552 (void)snprintf(cp, sizeof(new) - (cp - new), "%d", count); 2553 fd = open(new, O_RDWR|O_CREAT|O_EXCL, 0666); 2554 if (fd == -1) 2555 continue; 2556 if (nam) 2557 *nam = new; 2558 return (fd); 2559 } 2560 reply(452, "Unique file name cannot be created."); 2561 return (-1); 2562} 2563 2564/* 2565 * Format and send reply containing system error number. 2566 */ 2567void 2568perror_reply(int code, char *string) 2569{ 2570 2571 reply(code, "%s: %s.", string, strerror(errno)); 2572} 2573 2574static char *onefile[] = { 2575 "", 2576 0 2577}; 2578 2579void 2580send_file_list(char *whichf) 2581{ 2582 struct stat st; 2583 DIR *dirp = NULL; 2584 struct dirent *dir; 2585 FILE *dout = NULL; 2586 char **dirlist; 2587 char *dirname; 2588 int simple = 0; 2589 volatile int freeglob = 0; 2590 glob_t gl; 2591 2592 if (strpbrk(whichf, "~{[*?") != NULL) { 2593 memset(&gl, 0, sizeof(gl)); 2594 freeglob = 1; 2595 if (glob(whichf, 2596 GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE|GLOB_LIMIT, 2597 0, &gl)) { 2598 reply(550, "not found"); 2599 goto out; 2600 } else if (gl.gl_pathc == 0) { 2601 errno = ENOENT; 2602 perror_reply(550, whichf); 2603 goto out; 2604 } 2605 dirlist = gl.gl_pathv; 2606 } else { 2607 onefile[0] = whichf; 2608 dirlist = onefile; 2609 simple = 1; 2610 } 2611 2612 while ((dirname = *dirlist++)) { 2613 if (stat(dirname, &st) < 0) { 2614 /* 2615 * If user typed "ls -l", etc, and the client 2616 * used NLST, do what the user meant. 2617 */ 2618 if (dirname[0] == '-' && *dirlist == NULL && 2619 transflag == 0) { 2620 retrieve("/bin/ls %s", dirname); 2621 goto out; 2622 } 2623 perror_reply(550, whichf); 2624 if (dout != NULL) { 2625 (void) fclose(dout); 2626 transflag = 0; 2627 data = -1; 2628 pdata = -1; 2629 } 2630 goto out; 2631 } 2632 2633 if (S_ISREG(st.st_mode)) { 2634 if (dout == NULL) { 2635 dout = dataconn("file list", (off_t)-1, "w"); 2636 if (dout == NULL) 2637 goto out; 2638 transflag++; 2639 } 2640 fprintf(dout, "%s%s\n", dirname, 2641 type == TYPE_A ? "\r" : ""); 2642 byte_count += strlen(dirname) + 1; 2643 continue; 2644 } else if (!S_ISDIR(st.st_mode)) 2645 continue; 2646 2647 if ((dirp = opendir(dirname)) == NULL) 2648 continue; 2649 2650 while ((dir = readdir(dirp)) != NULL) { 2651 char nbuf[MAXPATHLEN]; 2652 2653 if (recvurg) { 2654 myoob(); 2655 recvurg = 0; 2656 transflag = 0; 2657 goto out; 2658 } 2659 2660 if (dir->d_name[0] == '.' && dir->d_namlen == 1) 2661 continue; 2662 if (dir->d_name[0] == '.' && dir->d_name[1] == '.' && 2663 dir->d_namlen == 2) 2664 continue; 2665 2666 snprintf(nbuf, sizeof(nbuf), "%s/%s", dirname, 2667 dir->d_name); 2668 2669 /* 2670 * We have to do a stat to insure it's 2671 * not a directory or special file. 2672 */ 2673 if (simple || (stat(nbuf, &st) == 0 && 2674 S_ISREG(st.st_mode))) { 2675 if (dout == NULL) { 2676 dout = dataconn("file list", (off_t)-1, 2677 "w"); 2678 if (dout == NULL) 2679 goto out; 2680 transflag++; 2681 } 2682 if (nbuf[0] == '.' && nbuf[1] == '/') 2683 fprintf(dout, "%s%s\n", &nbuf[2], 2684 type == TYPE_A ? "\r" : ""); 2685 else 2686 fprintf(dout, "%s%s\n", nbuf, 2687 type == TYPE_A ? "\r" : ""); 2688 byte_count += strlen(nbuf) + 1; 2689 } 2690 } 2691 (void) closedir(dirp); 2692 } 2693 2694 if (dout == NULL) 2695 reply(550, "No files found."); 2696 else if (ferror(dout) != 0) 2697 perror_reply(550, "Data connection"); 2698 else 2699 reply(226, "Transfer complete."); 2700 2701 transflag = 0; 2702 if (dout != NULL) 2703 (void) fclose(dout); 2704 else { 2705 if (pdata >= 0) 2706 close(pdata); 2707 } 2708 data = -1; 2709 pdata = -1; 2710out: 2711 if (freeglob) { 2712 freeglob = 0; 2713 globfree(&gl); 2714 } 2715} 2716 2717static void 2718reapchild(int signo) 2719{ 2720 int save_errno = errno; 2721 int rval; 2722 2723 do { 2724 rval = waitpid(-1, NULL, WNOHANG); 2725 } while (rval > 0 || (rval == -1 && errno == EINTR)); 2726 errno = save_errno; 2727} 2728 2729void 2730logxfer(char *name, off_t size, time_t start) 2731{ 2732 char buf[400 + MAXHOSTNAMELEN*4 + MAXPATHLEN*4]; 2733 char dir[MAXPATHLEN], path[MAXPATHLEN], rpath[MAXPATHLEN]; 2734 char vremotehost[MAXHOSTNAMELEN*4], vpath[MAXPATHLEN*4]; 2735 char *vpw; 2736 time_t now; 2737 int len; 2738 2739 if ((statfd >= 0) && (getcwd(dir, sizeof(dir)) != NULL)) { 2740 time(&now); 2741 2742 vpw = malloc(strlen(guest ? guestpw : pw->pw_name) * 4 + 1); 2743 if (vpw == NULL) 2744 return; 2745 2746 snprintf(path, sizeof(path), "%s/%s", dir, name); 2747 if (realpath(path, rpath) == NULL) 2748 strlcpy(rpath, path, sizeof(rpath)); 2749 strvis(vpath, rpath, VIS_SAFE|VIS_NOSLASH); 2750 2751 strvis(vremotehost, remotehost, VIS_SAFE|VIS_NOSLASH); 2752 strvis(vpw, guest? guestpw : pw->pw_name, VIS_SAFE|VIS_NOSLASH); 2753 2754 if ((len = snprintf(buf, sizeof(buf), 2755 "%.24s %d %s %qd %s %c %s %c %c %s ftp %d %s %s\n", 2756 ctime(&now), now - start + (now == start), 2757 vremotehost, (long long)size, vpath, 2758 ((type == TYPE_A) ? 'a' : 'b'), "*" /* none yet */, 2759 'o', ((guest) ? 'a' : 'r'), 2760 vpw, 0 /* none yet */, 2761 ((guest) ? "*" : pw->pw_name), dhostname)) >= sizeof(buf) 2762 || len < 0) { 2763 if ((len = strlen(buf)) == 0) 2764 return; /* should not happen */ 2765 buf[len - 1] = '\n'; 2766 } 2767 write(statfd, buf, len); 2768 free(vpw); 2769 } 2770} 2771 2772#if defined(TCPWRAPPERS) 2773static int 2774check_host(struct sockaddr *sa) 2775{ 2776 struct sockaddr_in *sin; 2777 struct hostent *hp; 2778 char *addr; 2779 2780 if (sa->sa_family != AF_INET) 2781 return 1; /*XXX*/ 2782 2783 sin = (struct sockaddr_in *)sa; 2784 hp = gethostbyaddr((char *)&sin->sin_addr, 2785 sizeof(struct in_addr), AF_INET); 2786 addr = inet_ntoa(sin->sin_addr); 2787 if (hp) { 2788 if (!hosts_ctl("ftpd", hp->h_name, addr, STRING_UNKNOWN)) { 2789 syslog(LOG_NOTICE, "tcpwrappers rejected: %s [%s]", 2790 hp->h_name, addr); 2791 return (0); 2792 } 2793 } else { 2794 if (!hosts_ctl("ftpd", STRING_UNKNOWN, addr, STRING_UNKNOWN)) { 2795 syslog(LOG_NOTICE, "tcpwrappers rejected: [%s]", addr); 2796 return (0); 2797 } 2798 } 2799 return (1); 2800} 2801#endif /* TCPWRAPPERS */ 2802 2803/* 2804 * Allocate space and return a copy of the specified dir. 2805 * If 'dir' begins with a tilde (~), expand it. 2806 */ 2807char * 2808copy_dir(char *dir, struct passwd *pw) 2809{ 2810 char *cp; 2811 char *newdir; 2812 char *user = NULL; 2813 size_t dirsiz; 2814 2815 /* Nothing to expand */ 2816 if (dir[0] != '~') 2817 return (strdup(dir)); 2818 2819 /* "dir" is of form ~user/some/dir, lookup user. */ 2820 if (dir[1] != '/' && dir[1] != '\0') { 2821 if ((cp = strchr(dir + 1, '/')) == NULL) 2822 cp = dir + strlen(dir); 2823 if ((user = malloc(cp - dir)) == NULL) 2824 return (NULL); 2825 strlcpy(user, dir + 1, cp - dir); 2826 2827 /* Only do lookup if it is a different user. */ 2828 if (strcmp(user, pw->pw_name) != 0) { 2829 if ((pw = getpwnam(user)) == NULL) { 2830 /* No such user, interpret literally */ 2831 free(user); 2832 return(strdup(dir)); 2833 } 2834 } 2835 } 2836 2837 /* 2838 * If there is no directory separator (/) then it is just pw_dir. 2839 * Otherwise, replace ~foo with pw_dir. 2840 */ 2841 if ((cp = strchr(dir + 1, '/')) == NULL) { 2842 newdir = strdup(pw->pw_dir); 2843 } else { 2844 dirsiz = strlen(cp) + strlen(pw->pw_dir) + 1; 2845 if ((newdir = malloc(dirsiz)) == NULL) { 2846 free(user); 2847 return (NULL); 2848 } 2849 strlcpy(newdir, pw->pw_dir, dirsiz); 2850 strlcat(newdir, cp, dirsiz); 2851 } 2852 2853 if (user) 2854 free(user); 2855 return(newdir); 2856} 2857