ftpd.c revision 1.155
1/* $OpenBSD: ftpd.c,v 1.155 2004/11/22 00:05:15 millert 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 1.155 2004/11/22 00:05:15 millert 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 (fd != -1) { 485 if (fork() == 0) 486 goto child; 487 close(fd); 488 } 489 } 490 } 491 492 child: 493 /* child */ 494 (void)dup2(fd, STDIN_FILENO); 495 (void)dup2(fd, STDOUT_FILENO); 496 for (i = 0; i < n; i++) 497 close(fds[i]); 498#if defined(TCPWRAPPERS) 499 /* ..in the child. */ 500 if (!check_host((struct sockaddr *)&his_addr)) 501 exit(1); 502#endif /* TCPWRAPPERS */ 503 } else { 504 addrlen = sizeof(his_addr); 505 if (getpeername(0, (struct sockaddr *)&his_addr, 506 &addrlen) < 0) { 507 /* syslog(LOG_ERR, "getpeername (%s): %m", argv[0]); */ 508 exit(1); 509 } 510 } 511 512 /* set this here so klogin can use it... */ 513 (void)snprintf(ttyline, sizeof(ttyline), "ftp%ld", (long)getpid()); 514 515 sa.sa_handler = SIG_DFL; 516 (void) sigaction(SIGCHLD, &sa, NULL); 517 518 sa.sa_handler = sigurg; 519 sa.sa_flags = 0; /* don't restart syscalls for SIGURG */ 520 (void) sigaction(SIGURG, &sa, NULL); 521 522 sigfillset(&sa.sa_mask); /* block all signals in handler */ 523 sa.sa_flags = SA_RESTART; 524 sa.sa_handler = sigquit; 525 (void) sigaction(SIGHUP, &sa, NULL); 526 (void) sigaction(SIGINT, &sa, NULL); 527 (void) sigaction(SIGQUIT, &sa, NULL); 528 (void) sigaction(SIGTERM, &sa, NULL); 529 530 sa.sa_handler = lostconn; 531 (void) sigaction(SIGPIPE, &sa, NULL); 532 533 sa.sa_handler = toolong; 534 (void) sigaction(SIGALRM, &sa, NULL); 535 536 addrlen = sizeof(ctrl_addr); 537 if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) { 538 syslog(LOG_ERR, "getsockname: %m"); 539 exit(1); 540 } 541 if (his_addr.su_family == AF_INET6 542 && IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr)) { 543#if 1 544 /* 545 * IPv4 control connection arrived to AF_INET6 socket. 546 * I hate to do this, but this is the easiest solution. 547 */ 548 union sockunion tmp_addr; 549 const int off = sizeof(struct in6_addr) - sizeof(struct in_addr); 550 551 tmp_addr = his_addr; 552 memset(&his_addr, 0, sizeof(his_addr)); 553 his_addr.su_sin.sin_family = AF_INET; 554 his_addr.su_sin.sin_len = sizeof(his_addr.su_sin); 555 memcpy(&his_addr.su_sin.sin_addr, 556 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 557 sizeof(his_addr.su_sin.sin_addr)); 558 his_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 559 560 tmp_addr = ctrl_addr; 561 memset(&ctrl_addr, 0, sizeof(ctrl_addr)); 562 ctrl_addr.su_sin.sin_family = AF_INET; 563 ctrl_addr.su_sin.sin_len = sizeof(ctrl_addr.su_sin); 564 memcpy(&ctrl_addr.su_sin.sin_addr, 565 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 566 sizeof(ctrl_addr.su_sin.sin_addr)); 567 ctrl_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 568#else 569 while (fgets(line, sizeof(line), fd) != NULL) { 570 if ((cp = strchr(line, '\n')) != NULL) 571 *cp = '\0'; 572 lreply(530, "%s", line); 573 } 574 (void) fflush(stdout); 575 (void) fclose(fd); 576 reply(530, 577 "Connection from IPv4 mapped address is not supported."); 578 exit(0); 579#endif 580 } 581#ifdef IP_TOS 582 if (his_addr.su_family == AF_INET) { 583 tos = IPTOS_LOWDELAY; 584 if (setsockopt(0, IPPROTO_IP, IP_TOS, (char *)&tos, 585 sizeof(int)) < 0) 586 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 587 } 588#endif 589 data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1); 590 591 /* Try to handle urgent data inline */ 592#ifdef SO_OOBINLINE 593 if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, (char *)&on, sizeof(on)) < 0) 594 syslog(LOG_ERR, "setsockopt: %m"); 595#endif 596 597#ifdef F_SETOWN 598 if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1) 599 syslog(LOG_ERR, "fcntl F_SETOWN: %m"); 600#endif 601 dolog((struct sockaddr *)&his_addr); 602 /* 603 * Set up default state 604 */ 605 data = -1; 606 type = TYPE_A; 607 form = FORM_N; 608 stru = STRU_F; 609 mode = MODE_S; 610 tmpline[0] = '\0'; 611 612 /* If logins are disabled, print out the message. */ 613 if ((fp = fopen(_PATH_NOLOGIN, "r")) != NULL) { 614 while (fgets(line, sizeof(line), fp) != NULL) { 615 if ((cp = strchr(line, '\n')) != NULL) 616 *cp = '\0'; 617 lreply(530, "%s", line); 618 } 619 (void) fflush(stdout); 620 (void) fclose(fp); 621 reply(530, "System not available."); 622 exit(0); 623 } 624 if ((fp = fopen(_PATH_FTPWELCOME, "r")) != NULL) { 625 while (fgets(line, sizeof(line), fp) != NULL) { 626 if ((cp = strchr(line, '\n')) != NULL) 627 *cp = '\0'; 628 lreply(220, "%s", line); 629 } 630 (void) fflush(stdout); 631 (void) fclose(fp); 632 /* reply(220,) must follow */ 633 } 634 (void) gethostname(hostname, sizeof(hostname)); 635 636 /* Make sure hostname is fully qualified. */ 637 hp = gethostbyname(hostname); 638 if (hp != NULL) 639 strlcpy(hostname, hp->h_name, sizeof(hostname)); 640 641 if (multihome) { 642 getnameinfo((struct sockaddr *)&ctrl_addr, ctrl_addr.su_len, 643 dhostname, sizeof(dhostname), NULL, 0, 0); 644 } 645 646 reply(220, "%s FTP server (%s) ready.", 647 (multihome ? dhostname : hostname), version); 648 for (;;) 649 (void) yyparse(); 650 /* NOTREACHED */ 651} 652 653/* 654 * Signal handlers. 655 */ 656 657static void 658lostconn(int signo) 659{ 660 struct syslog_data sdata = SYSLOG_DATA_INIT; 661 662 if (debug) 663 syslog_r(LOG_DEBUG, &sdata, "lost connection"); 664 dologout(1); 665} 666 667static void 668sigquit(int signo) 669{ 670 struct syslog_data sdata = SYSLOG_DATA_INIT; 671 672 syslog_r(LOG_ERR, &sdata, "got signal %s", sys_signame[signo]); 673 dologout(1); 674} 675 676/* 677 * Save the result of a getpwnam. Used for USER command, since 678 * the data returned must not be clobbered by any other command 679 * (e.g., globbing). 680 */ 681static struct passwd * 682sgetpwnam(char *name, struct passwd *pw) 683{ 684 static struct passwd *save; 685 struct passwd *old; 686 687 if (pw == NULL && (pw = getpwnam(name)) == NULL) 688 return (NULL); 689 old = save; 690 save = pw_dup(pw); 691 if (save == NULL) { 692 perror_reply(421, "Local resource failure: malloc"); 693 dologout(1); 694 /* NOTREACHED */ 695 } 696 if (old) { 697 memset(old->pw_passwd, 0, strlen(old->pw_passwd)); 698 free(old); 699 } 700 return (save); 701} 702 703static int login_attempts; /* number of failed login attempts */ 704static int askpasswd; /* had user command, ask for passwd */ 705static char curname[MAXLOGNAME]; /* current USER name */ 706 707/* 708 * USER command. 709 * Sets global passwd pointer pw if named account exists and is acceptable; 710 * sets askpasswd if a PASS command is expected. If logged in previously, 711 * need to reset state. If name is "ftp" or "anonymous", the name is not in 712 * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return. 713 * If account doesn't exist, ask for passwd anyway. Otherwise, check user 714 * requesting login privileges. Disallow anyone who does not have a standard 715 * shell as returned by getusershell(). Disallow anyone mentioned in the file 716 * _PATH_FTPUSERS to allow people such as root and uucp to be avoided. 717 */ 718void 719user(char *name) 720{ 721 char *cp, *shell, *style, *host; 722 char *class = NULL; 723 724 if (logged_in) 725 end_login(); 726 727 /* Close session from previous user if there was one. */ 728 if (as) { 729 auth_close(as); 730 as = NULL; 731 } 732 if (lc) { 733 login_close(lc); 734 lc = NULL; 735 } 736 737 if ((style = strchr(name, ':')) != NULL) 738 *style++ = 0; 739 740 guest = 0; 741 host = multihome ? dhostname : hostname; 742 if (anon_ok && 743 (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0)) { 744 if (checkuser(_PATH_FTPUSERS, "ftp") || 745 checkuser(_PATH_FTPUSERS, "anonymous")) 746 reply(530, "User %s access denied.", name); 747 else if ((pw = sgetpwnam("ftp", NULL)) != NULL) { 748 guest = 1; 749 askpasswd = 1; 750 lc = login_getclass(pw->pw_class); 751 if ((as = auth_open()) == NULL || 752 auth_setpwd(as, pw) != 0 || 753 auth_setoption(as, "FTPD_HOST", host) < 0) { 754 if (as) { 755 auth_close(as); 756 as = NULL; 757 } 758 login_close(lc); 759 lc = NULL; 760 reply(421, "Local resource failure"); 761 return; 762 } 763 reply(331, 764 "Guest login ok, send your email address as password."); 765 } else 766 reply(530, "User %s unknown.", name); 767 if (!askpasswd && logging) 768 syslog(LOG_NOTICE, 769 "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost); 770 return; 771 } 772 773 shell = _PATH_BSHELL; 774 if ((pw = sgetpwnam(name, NULL))) { 775 class = pw->pw_class; 776 if (pw->pw_shell != NULL && *pw->pw_shell != '\0') 777 shell = pw->pw_shell; 778 while ((cp = getusershell()) != NULL) 779 if (strcmp(cp, shell) == 0) 780 break; 781 shell = cp; 782 endusershell(); 783 } 784 785 /* Get login class; if invalid style treat like unknown user. */ 786 lc = login_getclass(class); 787 if (lc && (style = login_getstyle(lc, style, "auth-ftp")) == NULL) { 788 login_close(lc); 789 lc = NULL; 790 pw = NULL; 791 } 792 793 /* Do pre-authentication setup. */ 794 if (lc && ((as = auth_open()) == NULL || 795 (pw != NULL && auth_setpwd(as, pw) != 0) || 796 auth_setitem(as, AUTHV_STYLE, style) < 0 || 797 auth_setitem(as, AUTHV_NAME, name) < 0 || 798 auth_setitem(as, AUTHV_CLASS, class) < 0 || 799 auth_setoption(as, "login", "yes") < 0 || 800 auth_setoption(as, "notickets", "yes") < 0 || 801 auth_setoption(as, "FTPD_HOST", host) < 0)) { 802 if (as) { 803 auth_close(as); 804 as = NULL; 805 } 806 login_close(lc); 807 lc = NULL; 808 reply(421, "Local resource failure"); 809 return; 810 } 811 if (logging) 812 strlcpy(curname, name, sizeof(curname)); 813 814 dochroot = (lc && login_getcapbool(lc, "ftp-chroot", 0)) || 815 checkuser(_PATH_FTPCHROOT, name); 816 if (anon_only && !dochroot) { 817 if (anon_ok) 818 reply(530, "Sorry, only anonymous ftp allowed."); 819 else 820 reply(530, "User %s access denied.", name); 821 return; 822 } 823 if (pw) { 824 if ((!shell && !dochroot) || checkuser(_PATH_FTPUSERS, name)) { 825 reply(530, "User %s access denied.", name); 826 if (logging) 827 syslog(LOG_NOTICE, 828 "FTP LOGIN REFUSED FROM %s, %s", 829 remotehost, name); 830 pw = NULL; 831 return; 832 } 833 } 834 835 if (as != NULL && (cp = auth_challenge(as)) != NULL) 836 reply(331, "%s", cp); 837 else 838 reply(331, "Password required for %s.", name); 839 840 askpasswd = 1; 841 /* 842 * Delay before reading passwd after first failed 843 * attempt to slow down passwd-guessing programs. 844 */ 845 if (login_attempts) 846 sleep((unsigned) login_attempts); 847} 848 849/* 850 * Check if a user is in the file "fname" 851 */ 852static int 853checkuser(char *fname, char *name) 854{ 855 FILE *fp; 856 int found = 0; 857 char *p, line[BUFSIZ]; 858 859 if ((fp = fopen(fname, "r")) != NULL) { 860 while (fgets(line, sizeof(line), fp) != NULL) 861 if ((p = strchr(line, '\n')) != NULL) { 862 *p = '\0'; 863 if (line[0] == '#') 864 continue; 865 if (strcmp(line, name) == 0) { 866 found = 1; 867 break; 868 } 869 } 870 (void) fclose(fp); 871 } 872 return (found); 873} 874 875/* 876 * Terminate login as previous user, if any, resetting state; 877 * used when USER command is given or login fails. 878 */ 879static void 880end_login(void) 881{ 882 883 sigprocmask (SIG_BLOCK, &allsigs, NULL); 884 if (logged_in) { 885 ftpdlogwtmp(ttyline, "", ""); 886 if (doutmp) 887 ftpd_logout(utmp.ut_line); 888 } 889 reply(530, "Please reconnect to work as another user"); 890 exit(0); 891} 892 893void 894pass(char *passwd) 895{ 896 int authok, flags; 897 FILE *fp; 898 static char homedir[MAXPATHLEN]; 899 char *motd, *dir, rootdir[MAXPATHLEN]; 900 size_t sz_pw_dir; 901 902 if (logged_in || askpasswd == 0) { 903 reply(503, "Login with USER first."); 904 return; 905 } 906 askpasswd = 0; 907 if (!guest) { /* "ftp" is only account allowed no password */ 908 authok = 0; 909 if (pw == NULL || pw->pw_passwd[0] == '\0') { 910 useconds_t us; 911 912 /* Sleep between 1 and 3 seconds to emulate a crypt. */ 913 us = arc4random() % 3000000; 914 usleep(us); 915 if (as != NULL) { 916 auth_close(as); 917 as = NULL; 918 } 919 } else { 920 authok = auth_userresponse(as, passwd, 0); 921 as = NULL; 922 } 923 if (authok == 0) { 924 reply(530, "Login incorrect."); 925 if (logging) 926 syslog(LOG_NOTICE, 927 "FTP LOGIN FAILED FROM %s, %s", 928 remotehost, curname); 929 pw = NULL; 930 if (login_attempts++ >= 5) { 931 syslog(LOG_NOTICE, 932 "repeated login failures from %s", 933 remotehost); 934 exit(0); 935 } 936 return; 937 } 938 } else if (lc != NULL) { 939 /* Save anonymous' password. */ 940 if (guestpw != NULL) 941 free(guestpw); 942 guestpw = strdup(passwd); 943 if (guestpw == NULL) 944 fatal("Out of memory."); 945 946 authok = auth_approval(as, lc, pw->pw_name, "ftp"); 947 auth_close(as); 948 as = NULL; 949 if (authok == 0) { 950 syslog(LOG_INFO|LOG_AUTH, 951 "FTP LOGIN FAILED (HOST) as %s: approval failure.", 952 pw->pw_name); 953 reply(530, "Approval failure."); 954 exit(0); 955 } 956 } else { 957 syslog(LOG_INFO|LOG_AUTH, 958 "FTP LOGIN CLASS %s MISSING for %s: approval failure.", 959 pw->pw_class, pw->pw_name); 960 reply(530, "Permission denied."); 961 exit(0); 962 } 963 login_attempts = 0; /* this time successful */ 964 /* set umask via setusercontext() unless -u flag was given. */ 965 flags = LOGIN_SETGROUP|LOGIN_SETPRIORITY|LOGIN_SETRESOURCES; 966 if (umaskchange) 967 flags |= LOGIN_SETUMASK; 968 else 969 (void) umask(defumask); 970 if (setusercontext(lc, pw, (uid_t)0, flags) != 0) { 971 perror_reply(451, "Local resource failure: setusercontext"); 972 syslog(LOG_NOTICE, "setusercontext: %m"); 973 dologout(1); 974 /* NOTREACHED */ 975 } 976 977 /* open wtmp before chroot */ 978 ftpdlogwtmp(ttyline, pw->pw_name, remotehost); 979 980 /* open utmp before chroot */ 981 if (doutmp) { 982 memset((void *)&utmp, 0, sizeof(utmp)); 983 (void)time(&utmp.ut_time); 984 (void)strncpy(utmp.ut_name, pw->pw_name, sizeof(utmp.ut_name)); 985 (void)strncpy(utmp.ut_host, remotehost, sizeof(utmp.ut_host)); 986 (void)strncpy(utmp.ut_line, ttyline, sizeof(utmp.ut_line)); 987 ftpd_login(&utmp); 988 } 989 990 /* open stats file before chroot */ 991 if (guest && (stats == 1) && (statfd < 0)) 992 if ((statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND)) < 0) 993 stats = 0; 994 995 logged_in = 1; 996 997 if ((dir = login_getcapstr(lc, "ftp-dir", NULL, NULL))) { 998 char *newdir; 999 1000 newdir = copy_dir(dir, pw); 1001 if (newdir == NULL) { 1002 perror_reply(421, "Local resource failure: malloc"); 1003 dologout(1); 1004 /* NOTREACHED */ 1005 } 1006 pw->pw_dir = newdir; 1007 pw = sgetpwnam(NULL, pw); 1008 free(dir); 1009 free(newdir); 1010 } 1011 1012 /* make sure pw->pw_dir is big enough to hold "/" */ 1013 sz_pw_dir = strlen(pw->pw_dir) + 1; 1014 if (sz_pw_dir < 2) { 1015 pw->pw_dir = "/"; 1016 pw = sgetpwnam(NULL, pw); 1017 sz_pw_dir = 2; 1018 } 1019 1020 if (guest || dochroot) { 1021 if (multihome && guest) { 1022 struct stat ts; 1023 1024 /* Compute root directory. */ 1025 snprintf(rootdir, sizeof(rootdir), "%s/%s", 1026 pw->pw_dir, dhostname); 1027 if (stat(rootdir, &ts) < 0) { 1028 snprintf(rootdir, sizeof(rootdir), "%s/%s", 1029 pw->pw_dir, hostname); 1030 } 1031 } else 1032 strlcpy(rootdir, pw->pw_dir, sizeof(rootdir)); 1033 } 1034 if (guest) { 1035 /* 1036 * We MUST do a chdir() after the chroot. Otherwise 1037 * the old current directory will be accessible as "." 1038 * outside the new root! 1039 */ 1040 if (chroot(rootdir) < 0 || chdir("/") < 0) { 1041 reply(550, "Can't set guest privileges."); 1042 goto bad; 1043 } 1044 strlcpy(pw->pw_dir, "/", sz_pw_dir); 1045 if (setenv("HOME", "/", 1) == -1) { 1046 reply(550, "Can't setup environment."); 1047 goto bad; 1048 } 1049 } else if (dochroot) { 1050 if (chroot(rootdir) < 0 || chdir("/") < 0) { 1051 reply(550, "Can't change root."); 1052 goto bad; 1053 } 1054 strlcpy(pw->pw_dir, "/", sz_pw_dir); 1055 if (setenv("HOME", "/", 1) == -1) { 1056 reply(550, "Can't setup environment."); 1057 goto bad; 1058 } 1059 } else if (chdir(pw->pw_dir) < 0) { 1060 if (chdir("/") < 0) { 1061 reply(530, "User %s: can't change directory to %s.", 1062 pw->pw_name, pw->pw_dir); 1063 goto bad; 1064 } else 1065 lreply(230, "No directory! Logging in with home=/"); 1066 } 1067 if (seteuid(pw->pw_uid) < 0) { 1068 reply(550, "Can't set uid."); 1069 goto bad; 1070 } 1071 sigprocmask(SIG_UNBLOCK, &allsigs, NULL); 1072 1073 /* 1074 * Set home directory so that use of ~ (tilde) works correctly. 1075 */ 1076 if (getcwd(homedir, MAXPATHLEN) != NULL) { 1077 if (setenv("HOME", homedir, 1) == -1) { 1078 reply(550, "Can't setup environment."); 1079 goto bad; 1080 } 1081 } 1082 1083 /* 1084 * Display a login message, if it exists. 1085 * N.B. reply(230,) must follow the message. 1086 */ 1087 motd = login_getcapstr(lc, "welcome", NULL, NULL); 1088 if ((fp = fopen(motd ? motd : _PATH_FTPLOGINMESG, "r")) != NULL) { 1089 char *cp, line[LINE_MAX]; 1090 1091 while (fgets(line, sizeof(line), fp) != NULL) { 1092 if ((cp = strchr(line, '\n')) != NULL) 1093 *cp = '\0'; 1094 lreply(230, "%s", line); 1095 } 1096 (void) fflush(stdout); 1097 (void) fclose(fp); 1098 } 1099 if (motd != NULL) 1100 free(motd); 1101 if (guest) { 1102 if (ident != NULL) 1103 free(ident); 1104 ident = strdup(passwd); 1105 if (ident == NULL) 1106 fatal("Ran out of memory."); 1107 reply(230, "Guest login ok, access restrictions apply."); 1108#ifdef HASSETPROCTITLE 1109 snprintf(proctitle, sizeof(proctitle), 1110 "%s: anonymous/%.*s", remotehost, 1111 (int)(sizeof(proctitle) - sizeof(remotehost) - 1112 sizeof(": anonymous/")), passwd); 1113 setproctitle("%s", proctitle); 1114#endif /* HASSETPROCTITLE */ 1115 if (logging) 1116 syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s", 1117 remotehost, passwd); 1118 } else { 1119 reply(230, "User %s logged in.", pw->pw_name); 1120#ifdef HASSETPROCTITLE 1121 snprintf(proctitle, sizeof(proctitle), 1122 "%s: %s", remotehost, pw->pw_name); 1123 setproctitle("%s", proctitle); 1124#endif /* HASSETPROCTITLE */ 1125 if (logging) 1126 syslog(LOG_INFO, "FTP LOGIN FROM %s as %s", 1127 remotehost, pw->pw_name); 1128 } 1129 login_close(lc); 1130 lc = NULL; 1131 return; 1132bad: 1133 /* Forget all about it... */ 1134 login_close(lc); 1135 lc = NULL; 1136 end_login(); 1137} 1138 1139void 1140retrieve(char *cmd, char *name) 1141{ 1142 FILE *fin, *dout; 1143 struct stat st; 1144 int (*closefunc)(FILE *); 1145 time_t start; 1146 1147 if (cmd == 0) { 1148 fin = fopen(name, "r"), closefunc = fclose; 1149 st.st_size = 0; 1150 } else { 1151 char line[BUFSIZ]; 1152 1153 (void) snprintf(line, sizeof(line), cmd, name); 1154 name = line; 1155 fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose; 1156 st.st_size = -1; 1157 st.st_blksize = BUFSIZ; 1158 } 1159 if (fin == NULL) { 1160 if (errno != 0) { 1161 perror_reply(550, name); 1162 if (cmd == 0) { 1163 LOGCMD("get", name); 1164 } 1165 } 1166 return; 1167 } 1168 byte_count = -1; 1169 if (cmd == 0 && (fstat(fileno(fin), &st) < 0 || !S_ISREG(st.st_mode))) { 1170 reply(550, "%s: not a plain file.", name); 1171 goto done; 1172 } 1173 if (restart_point) { 1174 if (type == TYPE_A) { 1175 off_t i, n; 1176 int c; 1177 1178 n = restart_point; 1179 i = 0; 1180 while (i++ < n) { 1181 if ((c=getc(fin)) == EOF) { 1182 perror_reply(550, name); 1183 goto done; 1184 } 1185 if (c == '\n') 1186 i++; 1187 } 1188 } else if (lseek(fileno(fin), restart_point, SEEK_SET) < 0) { 1189 perror_reply(550, name); 1190 goto done; 1191 } 1192 } 1193 dout = dataconn(name, st.st_size, "w"); 1194 if (dout == NULL) 1195 goto done; 1196 time(&start); 1197 send_data(fin, dout, st.st_blksize, st.st_size, 1198 (restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode))); 1199 if ((cmd == 0) && stats) 1200 logxfer(name, byte_count, start); 1201 (void) fclose(dout); 1202 data = -1; 1203done: 1204 if (pdata >= 0) 1205 (void) close(pdata); 1206 pdata = -1; 1207 if (cmd == 0) 1208 LOGBYTES("get", name, byte_count); 1209 (*closefunc)(fin); 1210} 1211 1212void 1213store(char *name, char *mode, int unique) 1214{ 1215 FILE *fout, *din; 1216 int (*closefunc)(FILE *); 1217 struct stat st; 1218 int fd; 1219 1220 if (restart_point && *mode != 'a') 1221 mode = "r+"; 1222 1223 if (unique && stat(name, &st) == 0) { 1224 char *nam; 1225 1226 fd = guniquefd(name, &nam); 1227 if (fd == -1) { 1228 LOGCMD(*mode == 'w' ? "put" : "append", name); 1229 return; 1230 } 1231 name = nam; 1232 fout = fdopen(fd, mode); 1233 } else 1234 fout = fopen(name, mode); 1235 1236 closefunc = fclose; 1237 if (fout == NULL) { 1238 perror_reply(553, name); 1239 LOGCMD(*mode == 'w' ? "put" : "append", name); 1240 return; 1241 } 1242 byte_count = -1; 1243 if (restart_point) { 1244 if (type == TYPE_A) { 1245 off_t i, n; 1246 int c; 1247 1248 n = restart_point; 1249 i = 0; 1250 while (i++ < n) { 1251 if ((c=getc(fout)) == EOF) { 1252 perror_reply(550, name); 1253 goto done; 1254 } 1255 if (c == '\n') 1256 i++; 1257 } 1258 /* 1259 * We must do this seek to "current" position 1260 * because we are changing from reading to 1261 * writing. 1262 */ 1263 if (fseek(fout, 0L, SEEK_CUR) < 0) { 1264 perror_reply(550, name); 1265 goto done; 1266 } 1267 } else if (lseek(fileno(fout), restart_point, SEEK_SET) < 0) { 1268 perror_reply(550, name); 1269 goto done; 1270 } 1271 } 1272 din = dataconn(name, (off_t)-1, "r"); 1273 if (din == NULL) 1274 goto done; 1275 if (receive_data(din, fout) == 0) { 1276 if (unique) 1277 reply(226, "Transfer complete (unique file name:%s).", 1278 name); 1279 else 1280 reply(226, "Transfer complete."); 1281 } 1282 (void) fclose(din); 1283 data = -1; 1284 pdata = -1; 1285done: 1286 LOGBYTES(*mode == 'w' ? "put" : "append", name, byte_count); 1287 (*closefunc)(fout); 1288} 1289 1290static FILE * 1291getdatasock(char *mode) 1292{ 1293 int on = 1, s, t, tries; 1294 1295 if (data >= 0) 1296 return (fdopen(data, mode)); 1297 sigprocmask (SIG_BLOCK, &allsigs, NULL); 1298 (void) seteuid(0); 1299 s = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 1300 (void) seteuid((uid_t)pw->pw_uid); 1301 if (s < 0) 1302 goto bad; 1303 if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, 1304 (char *) &on, sizeof(on)) < 0) 1305 goto bad; 1306 /* anchor socket to avoid multi-homing problems */ 1307 data_source = ctrl_addr; 1308 data_source.su_port = htons(20); /* ftp-data port */ 1309 (void) seteuid(0); 1310 for (tries = 1; ; tries++) { 1311 if (bind(s, (struct sockaddr *)&data_source, 1312 data_source.su_len) >= 0) 1313 break; 1314 if (errno != EADDRINUSE || tries > 10) { 1315 (void) seteuid(pw->pw_uid); 1316 goto bad; 1317 } 1318 sleep(tries); 1319 } 1320 (void) seteuid((uid_t)pw->pw_uid); 1321 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1322 1323#ifdef IP_TOS 1324 if (ctrl_addr.su_family == AF_INET) { 1325 on = IPTOS_THROUGHPUT; 1326 if (setsockopt(s, IPPROTO_IP, IP_TOS, (char *)&on, 1327 sizeof(int)) < 0) 1328 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 1329 } 1330#endif 1331#ifdef TCP_NOPUSH 1332 /* 1333 * Turn off push flag to keep sender TCP from sending short packets 1334 * at the boundaries of each write(). Should probably do a SO_SNDBUF 1335 * to set the send buffer size as well, but that may not be desirable 1336 * in heavy-load situations. 1337 */ 1338 on = 1; 1339 if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, (char *)&on, sizeof(on)) < 0) 1340 syslog(LOG_WARNING, "setsockopt (TCP_NOPUSH): %m"); 1341#endif 1342#ifdef SO_SNDBUF 1343 on = 65536; 1344 if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, (char *)&on, sizeof(on)) < 0) 1345 syslog(LOG_WARNING, "setsockopt (SO_SNDBUF): %m"); 1346#endif 1347 1348 return (fdopen(s, mode)); 1349bad: 1350 /* Return the real value of errno (close may change it) */ 1351 t = errno; 1352 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1353 (void) close(s); 1354 errno = t; 1355 return (NULL); 1356} 1357 1358static FILE * 1359dataconn(char *name, off_t size, char *mode) 1360{ 1361 char sizebuf[32]; 1362 FILE *file; 1363 int retry = 0; 1364 in_port_t *p; 1365 u_char *fa, *ha; 1366 int alen; 1367 1368 file_size = size; 1369 byte_count = 0; 1370 if (size != (off_t) -1) { 1371 (void) snprintf(sizebuf, sizeof(sizebuf), " (%qd bytes)", 1372 size); 1373 } else 1374 sizebuf[0] = '\0'; 1375 if (pdata >= 0) { 1376 union sockunion from; 1377 int s; 1378 socklen_t fromlen = sizeof(from); 1379 1380 (void) alarm ((unsigned) timeout); 1381 s = accept(pdata, (struct sockaddr *)&from, &fromlen); 1382 (void) alarm (0); 1383 if (s < 0) { 1384 reply(425, "Can't open data connection."); 1385 (void) close(pdata); 1386 pdata = -1; 1387 return (NULL); 1388 } 1389 switch (from.su_family) { 1390 case AF_INET: 1391 p = (in_port_t *)&from.su_sin.sin_port; 1392 fa = (u_char *)&from.su_sin.sin_addr; 1393 ha = (u_char *)&his_addr.su_sin.sin_addr; 1394 alen = sizeof(struct in_addr); 1395 break; 1396 case AF_INET6: 1397 p = (in_port_t *)&from.su_sin6.sin6_port; 1398 fa = (u_char *)&from.su_sin6.sin6_addr; 1399 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1400 alen = sizeof(struct in6_addr); 1401 break; 1402 default: 1403 perror_reply(425, "Can't build data connection"); 1404 (void) close(pdata); 1405 (void) close(s); 1406 pdata = -1; 1407 return (NULL); 1408 } 1409 if (from.su_family != his_addr.su_family || 1410 ntohs(*p) < IPPORT_RESERVED) { 1411 perror_reply(425, "Can't build data connection"); 1412 (void) close(pdata); 1413 (void) close(s); 1414 pdata = -1; 1415 return (NULL); 1416 } 1417 if (portcheck && memcmp(fa, ha, alen) != 0) { 1418 perror_reply(435, "Can't build data connection"); 1419 (void) close(pdata); 1420 (void) close(s); 1421 pdata = -1; 1422 return (NULL); 1423 } 1424 (void) close(pdata); 1425 pdata = s; 1426 reply(150, "Opening %s mode data connection for '%s'%s.", 1427 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1428 return (fdopen(pdata, mode)); 1429 } 1430 if (data >= 0) { 1431 reply(125, "Using existing data connection for '%s'%s.", 1432 name, sizebuf); 1433 usedefault = 1; 1434 return (fdopen(data, mode)); 1435 } 1436 if (usedefault) 1437 data_dest = his_addr; 1438 usedefault = 1; 1439 do { 1440 file = getdatasock(mode); 1441 if (file == NULL) { 1442 char hbuf[MAXHOSTNAMELEN], pbuf[10]; 1443 1444 getnameinfo((struct sockaddr *)&data_source, 1445 data_source.su_len, hbuf, sizeof(hbuf), pbuf, 1446 sizeof(pbuf), NI_NUMERICHOST | NI_NUMERICSERV); 1447 reply(425, "Can't create data socket (%s,%s): %s.", 1448 hbuf, pbuf, strerror(errno)); 1449 return (NULL); 1450 } 1451 1452 /* 1453 * attempt to connect to reserved port on client machine; 1454 * this looks like an attack 1455 */ 1456 switch (data_dest.su_family) { 1457 case AF_INET: 1458 p = (in_port_t *)&data_dest.su_sin.sin_port; 1459 fa = (u_char *)&data_dest.su_sin.sin_addr; 1460 ha = (u_char *)&his_addr.su_sin.sin_addr; 1461 alen = sizeof(struct in_addr); 1462 break; 1463 case AF_INET6: 1464 p = (in_port_t *)&data_dest.su_sin6.sin6_port; 1465 fa = (u_char *)&data_dest.su_sin6.sin6_addr; 1466 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1467 alen = sizeof(struct in6_addr); 1468 break; 1469 default: 1470 perror_reply(425, "Can't build data connection"); 1471 (void) fclose(file); 1472 pdata = -1; 1473 return (NULL); 1474 } 1475 if (data_dest.su_family != his_addr.su_family || 1476 ntohs(*p) < IPPORT_RESERVED || ntohs(*p) == 2049) { /* XXX */ 1477 perror_reply(425, "Can't build data connection"); 1478 (void) fclose(file); 1479 return NULL; 1480 } 1481 if (portcheck && memcmp(fa, ha, alen) != 0) { 1482 perror_reply(435, "Can't build data connection"); 1483 (void) fclose(file); 1484 return NULL; 1485 } 1486 1487 if (connect(fileno(file), (struct sockaddr *)&data_dest, 1488 data_dest.su_len) == 0) { 1489 reply(150, "Opening %s mode data connection for '%s'%s.", 1490 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1491 data = fileno(file); 1492 return (file); 1493 } 1494 if (errno != EADDRINUSE) 1495 break; 1496 (void) fclose(file); 1497 sleep((unsigned) swaitint); 1498 retry += swaitint; 1499 } while (retry <= swaitmax); 1500 perror_reply(425, "Can't build data connection"); 1501 (void) fclose(file); 1502 return (NULL); 1503} 1504 1505/* 1506 * Tranfer the contents of "instr" to "outstr" peer using the appropriate 1507 * encapsulation of the data subject to Mode, Structure, and Type. 1508 * 1509 * NB: Form isn't handled. 1510 */ 1511static int 1512send_data(FILE *instr, FILE *outstr, off_t blksize, off_t filesize, int isreg) 1513{ 1514 int c, cnt, filefd, netfd; 1515 char *buf, *bp; 1516 size_t len; 1517 1518 transflag++; 1519 switch (type) { 1520 1521 case TYPE_A: 1522 while ((c = getc(instr)) != EOF) { 1523 if (recvurg) 1524 goto got_oob; 1525 byte_count++; 1526 if (c == '\n') { 1527 if (ferror(outstr)) 1528 goto data_err; 1529 (void) putc('\r', outstr); 1530 } 1531 (void) putc(c, outstr); 1532 } 1533 fflush(outstr); 1534 transflag = 0; 1535 if (ferror(instr)) 1536 goto file_err; 1537 if (ferror(outstr)) 1538 goto data_err; 1539 reply(226, "Transfer complete."); 1540 return(0); 1541 1542 case TYPE_I: 1543 case TYPE_L: 1544 /* 1545 * isreg is only set if we are not doing restart and we 1546 * are sending a regular file 1547 */ 1548 netfd = fileno(outstr); 1549 filefd = fileno(instr); 1550 1551 if (isreg && filesize < (off_t)16 * 1024 * 1024) { 1552 buf = mmap(0, filesize, PROT_READ, MAP_SHARED, filefd, 1553 (off_t)0); 1554 if (buf == MAP_FAILED) { 1555 syslog(LOG_WARNING, "mmap(%lu): %m", 1556 (unsigned long)filesize); 1557 goto oldway; 1558 } 1559 bp = buf; 1560 len = filesize; 1561 do { 1562 cnt = write(netfd, bp, len); 1563 if (recvurg) { 1564 munmap(buf, (size_t)filesize); 1565 goto got_oob; 1566 } 1567 len -= cnt; 1568 bp += cnt; 1569 if (cnt > 0) 1570 byte_count += cnt; 1571 } while(cnt > 0 && len > 0); 1572 1573 transflag = 0; 1574 munmap(buf, (size_t)filesize); 1575 if (cnt < 0) 1576 goto data_err; 1577 reply(226, "Transfer complete."); 1578 return(0); 1579 } 1580 1581oldway: 1582 if ((buf = malloc((u_int)blksize)) == NULL) { 1583 transflag = 0; 1584 perror_reply(451, "Local resource failure: malloc"); 1585 return(-1); 1586 } 1587 1588 while ((cnt = read(filefd, buf, (u_int)blksize)) > 0 && 1589 write(netfd, buf, cnt) == cnt) 1590 byte_count += cnt; 1591 transflag = 0; 1592 (void)free(buf); 1593 if (cnt != 0) { 1594 if (cnt < 0) 1595 goto file_err; 1596 goto data_err; 1597 } 1598 reply(226, "Transfer complete."); 1599 return(0); 1600 default: 1601 transflag = 0; 1602 reply(550, "Unimplemented TYPE %d in send_data", type); 1603 return(-1); 1604 } 1605 1606data_err: 1607 transflag = 0; 1608 perror_reply(426, "Data connection"); 1609 return(-1); 1610 1611file_err: 1612 transflag = 0; 1613 perror_reply(551, "Error on input file"); 1614 return(-1); 1615 1616got_oob: 1617 myoob(); 1618 recvurg = 0; 1619 transflag = 0; 1620 return(-1); 1621} 1622 1623/* 1624 * Transfer data from peer to "outstr" using the appropriate encapulation of 1625 * the data subject to Mode, Structure, and Type. 1626 * 1627 * N.B.: Form isn't handled. 1628 */ 1629static int 1630receive_data(FILE *instr, FILE *outstr) 1631{ 1632 int c; 1633 int cnt; 1634 char buf[BUFSIZ]; 1635 struct sigaction sa, sa_saved; 1636 volatile int bare_lfs = 0; 1637 1638 transflag++; 1639 switch (type) { 1640 1641 case TYPE_I: 1642 case TYPE_L: 1643 memset(&sa, 0, sizeof(sa)); 1644 sigfillset(&sa.sa_mask); 1645 sa.sa_flags = SA_RESTART; 1646 sa.sa_handler = lostconn; 1647 (void) sigaction(SIGALRM, &sa, &sa_saved); 1648 do { 1649 (void) alarm ((unsigned) timeout); 1650 cnt = read(fileno(instr), buf, sizeof(buf)); 1651 (void) alarm (0); 1652 if (recvurg) 1653 goto got_oob; 1654 1655 if (cnt > 0) { 1656 if (write(fileno(outstr), buf, cnt) != cnt) 1657 goto file_err; 1658 byte_count += cnt; 1659 } 1660 } while (cnt > 0); 1661 (void) sigaction(SIGALRM, &sa_saved, NULL); 1662 if (cnt < 0) 1663 goto data_err; 1664 transflag = 0; 1665 return (0); 1666 1667 case TYPE_E: 1668 reply(553, "TYPE E not implemented."); 1669 transflag = 0; 1670 return (-1); 1671 1672 case TYPE_A: 1673 while ((c = getc(instr)) != EOF) { 1674 if (recvurg) 1675 goto got_oob; 1676 byte_count++; 1677 if (c == '\n') 1678 bare_lfs++; 1679 while (c == '\r') { 1680 if (ferror(outstr)) 1681 goto data_err; 1682 if ((c = getc(instr)) != '\n') { 1683 (void) putc ('\r', outstr); 1684 if (c == '\0' || c == EOF) 1685 goto contin2; 1686 } 1687 } 1688 (void) putc(c, outstr); 1689 contin2: ; 1690 } 1691 fflush(outstr); 1692 if (ferror(instr)) 1693 goto data_err; 1694 if (ferror(outstr)) 1695 goto file_err; 1696 transflag = 0; 1697 if (bare_lfs) { 1698 lreply(226, 1699 "WARNING! %d bare linefeeds received in ASCII mode", 1700 bare_lfs); 1701 printf(" File may not have transferred correctly.\r\n"); 1702 } 1703 return (0); 1704 default: 1705 reply(550, "Unimplemented TYPE %d in receive_data", type); 1706 transflag = 0; 1707 return (-1); 1708 } 1709 1710data_err: 1711 transflag = 0; 1712 perror_reply(426, "Data Connection"); 1713 return (-1); 1714 1715file_err: 1716 transflag = 0; 1717 perror_reply(452, "Error writing file"); 1718 return (-1); 1719 1720got_oob: 1721 myoob(); 1722 recvurg = 0; 1723 transflag = 0; 1724 return (-1); 1725} 1726 1727void 1728statfilecmd(char *filename) 1729{ 1730 FILE *fin; 1731 int c; 1732 int atstart; 1733 char line[LINE_MAX]; 1734 1735 (void)snprintf(line, sizeof(line), "/bin/ls -lgA %s", filename); 1736 fin = ftpd_popen(line, "r"); 1737 lreply(211, "status of %s:", filename); 1738 atstart = 1; 1739 while ((c = getc(fin)) != EOF) { 1740 if (c == '\n') { 1741 if (ferror(stdout)){ 1742 perror_reply(421, "control connection"); 1743 (void) ftpd_pclose(fin); 1744 dologout(1); 1745 /* NOTREACHED */ 1746 } 1747 if (ferror(fin)) { 1748 perror_reply(551, filename); 1749 (void) ftpd_pclose(fin); 1750 return; 1751 } 1752 (void) putc('\r', stdout); 1753 } 1754 if (atstart && isdigit(c)) 1755 (void) putc(' ', stdout); 1756 (void) putc(c, stdout); 1757 atstart = (c == '\n'); 1758 } 1759 (void) ftpd_pclose(fin); 1760 reply(211, "End of Status"); 1761} 1762 1763void 1764statcmd(void) 1765{ 1766 union sockunion *su; 1767 u_char *a, *p; 1768 char hbuf[MAXHOSTNAMELEN]; 1769 int ispassive; 1770 1771 lreply(211, "%s FTP server status:", hostname); 1772 printf(" %s\r\n", version); 1773 getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len, 1774 hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST); 1775 printf(" Connected to %s", remotehost); 1776 if (strcmp(remotehost, hbuf) != 0) 1777 printf(" (%s)", hbuf); 1778 printf("\r\n"); 1779 if (logged_in) { 1780 if (guest) 1781 printf(" Logged in anonymously\r\n"); 1782 else 1783 printf(" Logged in as %s\r\n", pw->pw_name); 1784 } else if (askpasswd) 1785 printf(" Waiting for password\r\n"); 1786 else 1787 printf(" Waiting for user name\r\n"); 1788 printf(" TYPE: %s", typenames[type]); 1789 if (type == TYPE_A || type == TYPE_E) 1790 printf(", FORM: %s", formnames[form]); 1791 if (type == TYPE_L) 1792#if NBBY == 8 1793 printf(" %d", NBBY); 1794#else 1795 printf(" %d", bytesize); /* need definition! */ 1796#endif 1797 printf("; STRUcture: %s; transfer MODE: %s\r\n", 1798 strunames[stru], modenames[mode]); 1799 ispassive = 0; 1800 if (data != -1) 1801 printf(" Data connection open\r\n"); 1802 else if (pdata != -1) { 1803 printf(" in Passive mode\r\n"); 1804 su = (union sockunion *)&pasv_addr; 1805 ispassive++; 1806 goto printaddr; 1807 } else if (usedefault == 0) { 1808 su = (union sockunion *)&data_dest; 1809printaddr: 1810 /* PASV/PORT */ 1811 if (su->su_family == AF_INET) { 1812 if (ispassive) 1813 printf("211- PASV "); 1814 else 1815 printf("211- PORT "); 1816 a = (u_char *) &su->su_sin.sin_addr; 1817 p = (u_char *) &su->su_sin.sin_port; 1818 printf("(%u,%u,%u,%u,%u,%u)\r\n", 1819 a[0], a[1], a[2], a[3], 1820 p[0], p[1]); 1821 } 1822 1823 /* LPSV/LPRT */ 1824 { 1825 int alen, af, i; 1826 1827 alen = 0; 1828 switch (su->su_family) { 1829 case AF_INET: 1830 a = (u_char *) &su->su_sin.sin_addr; 1831 p = (u_char *) &su->su_sin.sin_port; 1832 alen = sizeof(su->su_sin.sin_addr); 1833 af = 4; 1834 break; 1835 case AF_INET6: 1836 a = (u_char *) &su->su_sin6.sin6_addr; 1837 p = (u_char *) &su->su_sin6.sin6_port; 1838 alen = sizeof(su->su_sin6.sin6_addr); 1839 af = 6; 1840 break; 1841 default: 1842 af = 0; 1843 break; 1844 } 1845 if (af) { 1846 if (ispassive) 1847 printf("211- LPSV "); 1848 else 1849 printf("211- LPRT "); 1850 printf("(%u,%u", af, alen); 1851 for (i = 0; i < alen; i++) 1852 printf(",%u", a[i]); 1853 printf(",%u,%u,%u)\r\n", 2, p[0], p[1]); 1854 } 1855 } 1856 1857 /* EPRT/EPSV */ 1858 { 1859 u_char af; 1860 1861 switch (su->su_family) { 1862 case AF_INET: 1863 af = 1; 1864 break; 1865 case AF_INET6: 1866 af = 2; 1867 break; 1868 default: 1869 af = 0; 1870 break; 1871 } 1872 if (af) { 1873 char hbuf[MAXHOSTNAMELEN], pbuf[10]; 1874 union sockunion tmp = *su; 1875 1876 if (tmp.su_family == AF_INET6) 1877 tmp.su_sin6.sin6_scope_id = 0; 1878 if (getnameinfo((struct sockaddr *)&tmp, tmp.su_len, 1879 hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), 1880 NI_NUMERICHOST | NI_NUMERICSERV) == 0) { 1881 if (ispassive) 1882 printf("211- EPSV "); 1883 else 1884 printf("211- EPRT "); 1885 printf("(|%u|%s|%s|)\r\n", 1886 af, hbuf, pbuf); 1887 } 1888 } 1889 } 1890 } else 1891 printf(" No data connection\r\n"); 1892 reply(211, "End of status"); 1893} 1894 1895void 1896fatal(char *s) 1897{ 1898 1899 reply(451, "Error in server: %s", s); 1900 reply(221, "Closing connection due to server error."); 1901 dologout(0); 1902 /* NOTREACHED */ 1903} 1904 1905void 1906reply(int n, const char *fmt, ...) 1907{ 1908 char *buf, *p, *next; 1909 int rval; 1910 va_list ap; 1911 1912 va_start(ap, fmt); 1913 rval = vasprintf(&buf, fmt, ap); 1914 va_end(ap); 1915 if (rval == -1 || buf == NULL) { 1916 printf("412 Local resource failure: malloc\r\n"); 1917 fflush(stdout); 1918 dologout(1); 1919 } 1920 next = buf; 1921 while ((p = strsep(&next, "\n\r"))) { 1922 printf("%d%s %s\r\n", n, (next != '\0') ? "-" : "", p); 1923 if (debug) 1924 syslog(LOG_DEBUG, "<--- %d%s %s", n, 1925 (next != '\0') ? "-" : "", p); 1926 } 1927 (void)fflush(stdout); 1928 free(buf); 1929} 1930 1931void 1932lreply(int n, const char *fmt, ...) 1933{ 1934 va_list ap; 1935 1936 va_start(ap, fmt); 1937 (void)printf("%d- ", n); 1938 (void)vprintf(fmt, ap); 1939 va_end(ap); 1940 (void)printf("\r\n"); 1941 (void)fflush(stdout); 1942 if (debug) { 1943 va_start(ap, fmt); 1944 syslog(LOG_DEBUG, "<--- %d- ", n); 1945 vsyslog(LOG_DEBUG, fmt, ap); 1946 va_end(ap); 1947 } 1948} 1949 1950static void 1951ack(char *s) 1952{ 1953 1954 reply(250, "%s command successful.", s); 1955} 1956 1957void 1958nack(char *s) 1959{ 1960 1961 reply(502, "%s command not implemented.", s); 1962} 1963 1964/* ARGSUSED */ 1965void 1966yyerror(char *s) 1967{ 1968 char *cp; 1969 1970 if ((cp = strchr(cbuf,'\n'))) 1971 *cp = '\0'; 1972 reply(500, "'%s': command not understood.", cbuf); 1973} 1974 1975void 1976delete(char *name) 1977{ 1978 struct stat st; 1979 1980 LOGCMD("delete", name); 1981 if (stat(name, &st) < 0) { 1982 perror_reply(550, name); 1983 return; 1984 } 1985 if ((st.st_mode&S_IFMT) == S_IFDIR) { 1986 if (rmdir(name) < 0) { 1987 perror_reply(550, name); 1988 return; 1989 } 1990 goto done; 1991 } 1992 if (unlink(name) < 0) { 1993 perror_reply(550, name); 1994 return; 1995 } 1996done: 1997 ack("DELE"); 1998} 1999 2000void 2001cwd(char *path) 2002{ 2003 FILE *message; 2004 2005 if (chdir(path) < 0) 2006 perror_reply(550, path); 2007 else { 2008 if ((message = fopen(_PATH_CWDMESG, "r")) != NULL) { 2009 char *cp, line[LINE_MAX]; 2010 2011 while (fgets(line, sizeof(line), message) != NULL) { 2012 if ((cp = strchr(line, '\n')) != NULL) 2013 *cp = '\0'; 2014 lreply(250, "%s", line); 2015 } 2016 (void) fflush(stdout); 2017 (void) fclose(message); 2018 } 2019 ack("CWD"); 2020 } 2021} 2022 2023void 2024replydirname(const char *name, const char *message) 2025{ 2026 char *p, *ep; 2027 char npath[MAXPATHLEN * 2]; 2028 2029 p = npath; 2030 ep = &npath[sizeof(npath) - 1]; 2031 while (*name) { 2032 if (*name == '"') { 2033 if (ep - p < 2) 2034 break; 2035 *p++ = *name++; 2036 *p++ = '"'; 2037 } else { 2038 if (ep - p < 1) 2039 break; 2040 *p++ = *name++; 2041 } 2042 } 2043 *p = '\0'; 2044 reply(257, "\"%s\" %s", npath, message); 2045} 2046 2047void 2048makedir(char *name) 2049{ 2050 2051 LOGCMD("mkdir", name); 2052 if (mkdir(name, 0777) < 0) 2053 perror_reply(550, name); 2054 else 2055 replydirname(name, "directory created."); 2056} 2057 2058void 2059removedir(char *name) 2060{ 2061 2062 LOGCMD("rmdir", name); 2063 if (rmdir(name) < 0) 2064 perror_reply(550, name); 2065 else 2066 ack("RMD"); 2067} 2068 2069void 2070pwd(void) 2071{ 2072 char path[MAXPATHLEN]; 2073 2074 if (getcwd(path, sizeof(path)) == NULL) 2075 perror_reply(550, "Can't get current directory"); 2076 else 2077 replydirname(path, "is current directory."); 2078} 2079 2080char * 2081renamefrom(char *name) 2082{ 2083 struct stat st; 2084 2085 if (stat(name, &st) < 0) { 2086 perror_reply(550, name); 2087 return ((char *)0); 2088 } 2089 reply(350, "File exists, ready for destination name"); 2090 return (name); 2091} 2092 2093void 2094renamecmd(char *from, char *to) 2095{ 2096 2097 LOGCMD2("rename", from, to); 2098 if (rename(from, to) < 0) 2099 perror_reply(550, "rename"); 2100 else 2101 ack("RNTO"); 2102} 2103 2104static void 2105dolog(struct sockaddr *sa) 2106{ 2107 char hbuf[sizeof(remotehost)]; 2108 2109 getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), NULL, 0, 0); 2110 (void) strlcpy(remotehost, hbuf, sizeof(remotehost)); 2111 2112#ifdef HASSETPROCTITLE 2113 snprintf(proctitle, sizeof(proctitle), "%s: connected", remotehost); 2114 setproctitle("%s", proctitle); 2115#endif /* HASSETPROCTITLE */ 2116 2117 if (logging) 2118 syslog(LOG_INFO, "connection from %s", remotehost); 2119} 2120 2121/* 2122 * Record logout in wtmp file and exit with supplied status. 2123 * NOTE: because this is called from signal handlers it cannot 2124 * use stdio (or call other functions that use stdio). 2125 */ 2126void 2127dologout(int status) 2128{ 2129 2130 transflag = 0; 2131 2132 if (logged_in) { 2133 sigprocmask(SIG_BLOCK, &allsigs, NULL); 2134 ftpdlogwtmp(ttyline, "", ""); 2135 if (doutmp) 2136 ftpd_logout(utmp.ut_line); 2137 } 2138 /* beware of flushing buffers after a SIGPIPE */ 2139 _exit(status); 2140} 2141 2142static void 2143sigurg(int signo) 2144{ 2145 2146 recvurg = 1; 2147} 2148 2149static void 2150myoob(void) 2151{ 2152 char *cp; 2153 2154 /* only process if transfer occurring */ 2155 if (!transflag) 2156 return; 2157 cp = tmpline; 2158 if (getline(cp, 7, stdin) == NULL) { 2159 reply(221, "You could at least say goodbye."); 2160 dologout(0); 2161 } 2162 upper(cp); 2163 if (strcmp(cp, "ABOR\r\n") == 0) { 2164 tmpline[0] = '\0'; 2165 reply(426, "Transfer aborted. Data connection closed."); 2166 reply(226, "Abort successful"); 2167 } 2168 if (strcmp(cp, "STAT\r\n") == 0) { 2169 tmpline[0] = '\0'; 2170 if (file_size != (off_t) -1) 2171 reply(213, "Status: %qd of %qd bytes transferred", 2172 byte_count, file_size); 2173 else 2174 reply(213, "Status: %qd bytes transferred", byte_count); 2175 } 2176} 2177 2178/* 2179 * Note: a response of 425 is not mentioned as a possible response to 2180 * the PASV command in RFC959. However, it has been blessed as 2181 * a legitimate response by Jon Postel in a telephone conversation 2182 * with Rick Adams on 25 Jan 89. 2183 */ 2184void 2185passive(void) 2186{ 2187 socklen_t len; 2188 int on; 2189 u_char *p, *a; 2190 2191 if (pw == NULL) { 2192 reply(530, "Please login with USER and PASS"); 2193 return; 2194 } 2195 if (pdata >= 0) 2196 close(pdata); 2197 /* 2198 * XXX 2199 * At this point, it would be nice to have an algorithm that 2200 * inserted a growing delay in an attack scenario. Such a thing 2201 * would look like continual passive sockets being opened, but 2202 * nothing serious being done with them. They're not used to 2203 * move data; the entire attempt is just to use tcp FIN_WAIT 2204 * resources. 2205 */ 2206 pdata = socket(AF_INET, SOCK_STREAM, 0); 2207 if (pdata < 0) { 2208 perror_reply(425, "Can't open passive connection"); 2209 return; 2210 } 2211 2212 on = IP_PORTRANGE_HIGH; 2213 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2214 (char *)&on, sizeof(on)) < 0) 2215 goto pasv_error; 2216 2217 pasv_addr = ctrl_addr; 2218 pasv_addr.su_sin.sin_port = 0; 2219 if (bind(pdata, (struct sockaddr *)&pasv_addr, 2220 pasv_addr.su_len) < 0) 2221 goto pasv_error; 2222 2223 len = sizeof(pasv_addr); 2224 if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0) 2225 goto pasv_error; 2226 if (listen(pdata, 1) < 0) 2227 goto pasv_error; 2228 a = (u_char *) &pasv_addr.su_sin.sin_addr; 2229 p = (u_char *) &pasv_addr.su_sin.sin_port; 2230 2231 reply(227, "Entering Passive Mode (%u,%u,%u,%u,%u,%u)", a[0], 2232 a[1], a[2], a[3], p[0], p[1]); 2233 return; 2234 2235pasv_error: 2236 (void) close(pdata); 2237 pdata = -1; 2238 perror_reply(425, "Can't open passive connection"); 2239 return; 2240} 2241 2242/* 2243 * convert protocol identifier to/from AF 2244 */ 2245int 2246lpsvproto2af(int proto) 2247{ 2248 2249 switch (proto) { 2250 case 4: return AF_INET; 2251#ifdef INET6 2252 case 6: return AF_INET6; 2253#endif 2254 default: return -1; 2255 } 2256} 2257 2258int 2259af2lpsvproto(int af) 2260{ 2261 2262 switch (af) { 2263 case AF_INET: return 4; 2264#ifdef INET6 2265 case AF_INET6: return 6; 2266#endif 2267 default: return -1; 2268 } 2269} 2270 2271int 2272epsvproto2af(int proto) 2273{ 2274 2275 switch (proto) { 2276 case 1: return AF_INET; 2277#ifdef INET6 2278 case 2: return AF_INET6; 2279#endif 2280 default: return -1; 2281 } 2282} 2283 2284int 2285af2epsvproto(int af) 2286{ 2287 2288 switch (af) { 2289 case AF_INET: return 1; 2290#ifdef INET6 2291 case AF_INET6: return 2; 2292#endif 2293 default: return -1; 2294 } 2295} 2296 2297/* 2298 * 228 Entering Long Passive Mode (af, hal, h1, h2, h3,..., pal, p1, p2...) 2299 * 229 Entering Extended Passive Mode (|||port|) 2300 */ 2301void 2302long_passive(char *cmd, int pf) 2303{ 2304 socklen_t len; 2305 int on; 2306 u_char *p, *a; 2307 2308 if (!logged_in) { 2309 syslog(LOG_NOTICE, "long passive but not logged in"); 2310 reply(503, "Login with USER first."); 2311 return; 2312 } 2313 2314 if (pf != PF_UNSPEC && ctrl_addr.su_family != pf) { 2315 /* 2316 * XXX 2317 * only EPRT/EPSV ready clients will understand this 2318 */ 2319 if (strcmp(cmd, "EPSV") != 0) 2320 reply(501, "Network protocol mismatch"); /*XXX*/ 2321 else 2322 epsv_protounsupp("Network protocol mismatch"); 2323 2324 return; 2325 } 2326 2327 if (pdata >= 0) 2328 close(pdata); 2329 /* 2330 * XXX 2331 * At this point, it would be nice to have an algorithm that 2332 * inserted a growing delay in an attack scenario. Such a thing 2333 * would look like continual passive sockets being opened, but 2334 * nothing serious being done with them. They not used to move 2335 * data; the entire attempt is just to use tcp FIN_WAIT 2336 * resources. 2337 */ 2338 pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 2339 if (pdata < 0) { 2340 perror_reply(425, "Can't open passive connection"); 2341 return; 2342 } 2343 2344 switch (ctrl_addr.su_family) { 2345 case AF_INET: 2346 on = IP_PORTRANGE_HIGH; 2347 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2348 (char *)&on, sizeof(on)) < 0) 2349 goto pasv_error; 2350 break; 2351 case AF_INET6: 2352 on = IPV6_PORTRANGE_HIGH; 2353 if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE, 2354 (char *)&on, sizeof(on)) < 0) 2355 goto pasv_error; 2356 break; 2357 } 2358 2359 pasv_addr = ctrl_addr; 2360 pasv_addr.su_port = 0; 2361 if (bind(pdata, (struct sockaddr *) &pasv_addr, pasv_addr.su_len) < 0) 2362 goto pasv_error; 2363 len = pasv_addr.su_len; 2364 if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0) 2365 goto pasv_error; 2366 if (listen(pdata, 1) < 0) 2367 goto pasv_error; 2368 p = (u_char *) &pasv_addr.su_port; 2369 2370 if (strcmp(cmd, "LPSV") == 0) { 2371 switch (pasv_addr.su_family) { 2372 case AF_INET: 2373 a = (u_char *) &pasv_addr.su_sin.sin_addr; 2374 reply(228, 2375 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2376 4, 4, a[0], a[1], a[2], a[3], 2, p[0], p[1]); 2377 return; 2378 case AF_INET6: 2379 a = (u_char *) &pasv_addr.su_sin6.sin6_addr; 2380 reply(228, 2381 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u," 2382 "%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2383 6, 16, a[0], a[1], a[2], a[3], a[4], 2384 a[5], a[6], a[7], a[8], a[9], a[10], 2385 a[11], a[12], a[13], a[14], a[15], 2386 2, p[0], p[1]); 2387 return; 2388 } 2389 } else if (strcmp(cmd, "EPSV") == 0) { 2390 switch (pasv_addr.su_family) { 2391 case AF_INET: 2392 case AF_INET6: 2393 reply(229, "Entering Extended Passive Mode (|||%u|)", 2394 ntohs(pasv_addr.su_port)); 2395 return; 2396 } 2397 } else { 2398 /* more proper error code? */ 2399 } 2400 2401 pasv_error: 2402 (void) close(pdata); 2403 pdata = -1; 2404 perror_reply(425, "Can't open passive connection"); 2405 return; 2406} 2407 2408/* 2409 * EPRT |proto|addr|port| 2410 */ 2411int 2412extended_port(const char *arg) 2413{ 2414 char *tmp = NULL; 2415 char *result[3]; 2416 char *p, *q; 2417 char delim; 2418 struct addrinfo hints; 2419 struct addrinfo *res = NULL; 2420 int i; 2421 unsigned long proto; 2422 2423 if (epsvall) { 2424 reply(501, "EPRT disallowed after EPSV ALL"); 2425 return -1; 2426 } 2427 2428 usedefault = 0; 2429 if (pdata >= 0) { 2430 (void) close(pdata); 2431 pdata = -1; 2432 } 2433 2434 tmp = strdup(arg); 2435 if (!tmp) { 2436 fatal("not enough core."); 2437 /*NOTREACHED*/ 2438 } 2439 p = tmp; 2440 delim = p[0]; 2441 p++; 2442 memset(result, 0, sizeof(result)); 2443 for (i = 0; i < 3; i++) { 2444 q = strchr(p, delim); 2445 if (!q || *q != delim) 2446 goto parsefail; 2447 *q++ = '\0'; 2448 result[i] = p; 2449 p = q; 2450 } 2451 2452 /* some more sanity check */ 2453 p = NULL; 2454 (void)strtoul(result[2], &p, 10); 2455 if (!*result[2] || *p) 2456 goto protounsupp; 2457 p = NULL; 2458 proto = strtoul(result[0], &p, 10); 2459 if (!*result[0] || *p) 2460 goto protounsupp; 2461 2462 memset(&hints, 0, sizeof(hints)); 2463 hints.ai_family = epsvproto2af((int)proto); 2464 if (hints.ai_family < 0) 2465 goto protounsupp; 2466 hints.ai_socktype = SOCK_STREAM; 2467 hints.ai_flags = AI_NUMERICHOST; /*no DNS*/ 2468 if (getaddrinfo(result[1], result[2], &hints, &res)) 2469 goto parsefail; 2470 if (res->ai_next) 2471 goto parsefail; 2472 if (sizeof(data_dest) < res->ai_addrlen) 2473 goto parsefail; 2474 memcpy(&data_dest, res->ai_addr, res->ai_addrlen); 2475 if (his_addr.su_family == AF_INET6 && 2476 data_dest.su_family == AF_INET6) { 2477 /* XXX more sanity checks! */ 2478 data_dest.su_sin6.sin6_scope_id = 2479 his_addr.su_sin6.sin6_scope_id; 2480 } 2481 if (pdata >= 0) { 2482 (void) close(pdata); 2483 pdata = -1; 2484 } 2485 reply(200, "EPRT command successful."); 2486 2487 if (tmp) 2488 free(tmp); 2489 if (res) 2490 freeaddrinfo(res); 2491 return 0; 2492 2493parsefail: 2494 reply(500, "Invalid argument, rejected."); 2495 usedefault = 1; 2496 if (tmp) 2497 free(tmp); 2498 if (res) 2499 freeaddrinfo(res); 2500 return -1; 2501 2502protounsupp: 2503 epsv_protounsupp("Protocol not supported"); 2504 usedefault = 1; 2505 if (tmp) 2506 free(tmp); 2507 if (res) 2508 freeaddrinfo(res); 2509 return -1; 2510} 2511 2512/* 2513 * 522 Protocol not supported (proto,...) 2514 * as we assume address family for control and data connections are the same, 2515 * we do not return the list of address families we support - instead, we 2516 * return the address family of the control connection. 2517 */ 2518void 2519epsv_protounsupp(const char *message) 2520{ 2521 int proto; 2522 2523 proto = af2epsvproto(ctrl_addr.su_family); 2524 if (proto < 0) 2525 reply(501, "%s", message); /*XXX*/ 2526 else 2527 reply(522, "%s, use (%d)", message, proto); 2528} 2529 2530/* 2531 * Generate unique name for file with basename "local". 2532 * The file named "local" is already known to exist. 2533 * Generates failure reply on error. 2534 */ 2535static int 2536guniquefd(char *local, char **nam) 2537{ 2538 static char new[MAXPATHLEN]; 2539 struct stat st; 2540 int count, len, fd; 2541 char *cp; 2542 2543 cp = strrchr(local, '/'); 2544 if (cp) 2545 *cp = '\0'; 2546 if (stat(cp ? local : ".", &st) < 0) { 2547 perror_reply(553, cp ? local : "."); 2548 return (-1); 2549 } 2550 if (cp) 2551 *cp = '/'; 2552 len = strlcpy(new, local, sizeof(new)); 2553 if (len+2+1 >= sizeof(new)-1) 2554 return (-1); 2555 cp = new + len; 2556 *cp++ = '.'; 2557 for (count = 1; count < 100; count++) { 2558 (void)snprintf(cp, sizeof(new) - (cp - new), "%d", count); 2559 fd = open(new, O_RDWR|O_CREAT|O_EXCL, 0666); 2560 if (fd == -1) 2561 continue; 2562 if (nam) 2563 *nam = new; 2564 return (fd); 2565 } 2566 reply(452, "Unique file name cannot be created."); 2567 return (-1); 2568} 2569 2570/* 2571 * Format and send reply containing system error number. 2572 */ 2573void 2574perror_reply(int code, char *string) 2575{ 2576 2577 reply(code, "%s: %s.", string, strerror(errno)); 2578} 2579 2580static char *onefile[] = { 2581 "", 2582 0 2583}; 2584 2585void 2586send_file_list(char *whichf) 2587{ 2588 struct stat st; 2589 DIR *dirp = NULL; 2590 struct dirent *dir; 2591 FILE *dout = NULL; 2592 char **dirlist; 2593 char *dirname; 2594 int simple = 0; 2595 volatile int freeglob = 0; 2596 glob_t gl; 2597 2598 if (strpbrk(whichf, "~{[*?") != NULL) { 2599 memset(&gl, 0, sizeof(gl)); 2600 freeglob = 1; 2601 if (glob(whichf, 2602 GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE|GLOB_LIMIT, 2603 0, &gl)) { 2604 reply(550, "not found"); 2605 goto out; 2606 } else if (gl.gl_pathc == 0) { 2607 errno = ENOENT; 2608 perror_reply(550, whichf); 2609 goto out; 2610 } 2611 dirlist = gl.gl_pathv; 2612 } else { 2613 onefile[0] = whichf; 2614 dirlist = onefile; 2615 simple = 1; 2616 } 2617 2618 while ((dirname = *dirlist++)) { 2619 if (stat(dirname, &st) < 0) { 2620 /* 2621 * If user typed "ls -l", etc, and the client 2622 * used NLST, do what the user meant. 2623 */ 2624 if (dirname[0] == '-' && *dirlist == NULL && 2625 transflag == 0) { 2626 retrieve("/bin/ls %s", dirname); 2627 goto out; 2628 } 2629 perror_reply(550, whichf); 2630 if (dout != NULL) { 2631 (void) fclose(dout); 2632 transflag = 0; 2633 data = -1; 2634 pdata = -1; 2635 } 2636 goto out; 2637 } 2638 2639 if (S_ISREG(st.st_mode)) { 2640 if (dout == NULL) { 2641 dout = dataconn("file list", (off_t)-1, "w"); 2642 if (dout == NULL) 2643 goto out; 2644 transflag++; 2645 } 2646 fprintf(dout, "%s%s\n", dirname, 2647 type == TYPE_A ? "\r" : ""); 2648 byte_count += strlen(dirname) + 1; 2649 continue; 2650 } else if (!S_ISDIR(st.st_mode)) 2651 continue; 2652 2653 if ((dirp = opendir(dirname)) == NULL) 2654 continue; 2655 2656 while ((dir = readdir(dirp)) != NULL) { 2657 char nbuf[MAXPATHLEN]; 2658 2659 if (recvurg) { 2660 myoob(); 2661 recvurg = 0; 2662 transflag = 0; 2663 goto out; 2664 } 2665 2666 if (dir->d_name[0] == '.' && dir->d_namlen == 1) 2667 continue; 2668 if (dir->d_name[0] == '.' && dir->d_name[1] == '.' && 2669 dir->d_namlen == 2) 2670 continue; 2671 2672 snprintf(nbuf, sizeof(nbuf), "%s/%s", dirname, 2673 dir->d_name); 2674 2675 /* 2676 * We have to do a stat to insure it's 2677 * not a directory or special file. 2678 */ 2679 if (simple || (stat(nbuf, &st) == 0 && 2680 S_ISREG(st.st_mode))) { 2681 if (dout == NULL) { 2682 dout = dataconn("file list", (off_t)-1, 2683 "w"); 2684 if (dout == NULL) 2685 goto out; 2686 transflag++; 2687 } 2688 if (nbuf[0] == '.' && nbuf[1] == '/') 2689 fprintf(dout, "%s%s\n", &nbuf[2], 2690 type == TYPE_A ? "\r" : ""); 2691 else 2692 fprintf(dout, "%s%s\n", nbuf, 2693 type == TYPE_A ? "\r" : ""); 2694 byte_count += strlen(nbuf) + 1; 2695 } 2696 } 2697 (void) closedir(dirp); 2698 } 2699 2700 if (dout == NULL) 2701 reply(550, "No files found."); 2702 else if (ferror(dout) != 0) 2703 perror_reply(550, "Data connection"); 2704 else 2705 reply(226, "Transfer complete."); 2706 2707 transflag = 0; 2708 if (dout != NULL) 2709 (void) fclose(dout); 2710 else { 2711 if (pdata >= 0) 2712 close(pdata); 2713 } 2714 data = -1; 2715 pdata = -1; 2716out: 2717 if (freeglob) { 2718 freeglob = 0; 2719 globfree(&gl); 2720 } 2721} 2722 2723static void 2724reapchild(int signo) 2725{ 2726 int save_errno = errno; 2727 int rval; 2728 2729 do { 2730 rval = waitpid(-1, NULL, WNOHANG); 2731 } while (rval > 0 || (rval == -1 && errno == EINTR)); 2732 errno = save_errno; 2733} 2734 2735void 2736logxfer(char *name, off_t size, time_t start) 2737{ 2738 char buf[400 + MAXHOSTNAMELEN*4 + MAXPATHLEN*4]; 2739 char dir[MAXPATHLEN], path[MAXPATHLEN], rpath[MAXPATHLEN]; 2740 char vremotehost[MAXHOSTNAMELEN*4], vpath[MAXPATHLEN*4]; 2741 char *vpw; 2742 time_t now; 2743 int len; 2744 2745 if ((statfd >= 0) && (getcwd(dir, sizeof(dir)) != NULL)) { 2746 time(&now); 2747 2748 vpw = malloc(strlen(guest ? guestpw : pw->pw_name) * 4 + 1); 2749 if (vpw == NULL) 2750 return; 2751 2752 snprintf(path, sizeof(path), "%s/%s", dir, name); 2753 if (realpath(path, rpath) == NULL) 2754 strlcpy(rpath, path, sizeof(rpath)); 2755 strvis(vpath, rpath, VIS_SAFE|VIS_NOSLASH); 2756 2757 strvis(vremotehost, remotehost, VIS_SAFE|VIS_NOSLASH); 2758 strvis(vpw, guest? guestpw : pw->pw_name, VIS_SAFE|VIS_NOSLASH); 2759 2760 if ((len = snprintf(buf, sizeof(buf), 2761 "%.24s %d %s %qd %s %c %s %c %c %s ftp %d %s %s\n", 2762 ctime(&now), 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)) >= sizeof(buf) 2768 || len < 0) { 2769 if ((len = strlen(buf)) == 0) 2770 return; /* should not happen */ 2771 buf[len - 1] = '\n'; 2772 } 2773 write(statfd, buf, len); 2774 free(vpw); 2775 } 2776} 2777 2778#if defined(TCPWRAPPERS) 2779static int 2780check_host(struct sockaddr *sa) 2781{ 2782 struct sockaddr_in *sin; 2783 struct hostent *hp; 2784 char *addr; 2785 2786 if (sa->sa_family != AF_INET) 2787 return 1; /*XXX*/ 2788 2789 sin = (struct sockaddr_in *)sa; 2790 hp = gethostbyaddr((char *)&sin->sin_addr, 2791 sizeof(struct in_addr), AF_INET); 2792 addr = inet_ntoa(sin->sin_addr); 2793 if (hp) { 2794 if (!hosts_ctl("ftpd", hp->h_name, addr, STRING_UNKNOWN)) { 2795 syslog(LOG_NOTICE, "tcpwrappers rejected: %s [%s]", 2796 hp->h_name, addr); 2797 return (0); 2798 } 2799 } else { 2800 if (!hosts_ctl("ftpd", STRING_UNKNOWN, addr, STRING_UNKNOWN)) { 2801 syslog(LOG_NOTICE, "tcpwrappers rejected: [%s]", addr); 2802 return (0); 2803 } 2804 } 2805 return (1); 2806} 2807#endif /* TCPWRAPPERS */ 2808 2809/* 2810 * Allocate space and return a copy of the specified dir. 2811 * If 'dir' begins with a tilde (~), expand it. 2812 */ 2813char * 2814copy_dir(char *dir, struct passwd *pw) 2815{ 2816 char *cp; 2817 char *newdir; 2818 char *user = NULL; 2819 size_t dirsiz; 2820 2821 /* Nothing to expand */ 2822 if (dir[0] != '~') 2823 return (strdup(dir)); 2824 2825 /* "dir" is of form ~user/some/dir, lookup user. */ 2826 if (dir[1] != '/' && dir[1] != '\0') { 2827 if ((cp = strchr(dir + 1, '/')) == NULL) 2828 cp = dir + strlen(dir); 2829 if ((user = malloc(cp - dir)) == NULL) 2830 return (NULL); 2831 strlcpy(user, dir + 1, cp - dir); 2832 2833 /* Only do lookup if it is a different user. */ 2834 if (strcmp(user, pw->pw_name) != 0) { 2835 if ((pw = getpwnam(user)) == NULL) { 2836 /* No such user, interpret literally */ 2837 free(user); 2838 return(strdup(dir)); 2839 } 2840 } 2841 } 2842 2843 /* 2844 * If there is no directory separator (/) then it is just pw_dir. 2845 * Otherwise, replace ~foo with pw_dir. 2846 */ 2847 if ((cp = strchr(dir + 1, '/')) == NULL) { 2848 newdir = strdup(pw->pw_dir); 2849 } else { 2850 dirsiz = strlen(cp) + strlen(pw->pw_dir) + 1; 2851 if ((newdir = malloc(dirsiz)) == NULL) { 2852 free(user); 2853 return (NULL); 2854 } 2855 strlcpy(newdir, pw->pw_dir, dirsiz); 2856 strlcat(newdir, cp, dirsiz); 2857 } 2858 2859 if (user) 2860 free(user); 2861 return(newdir); 2862} 2863