ftpd.c revision 1.126
1/* $OpenBSD: ftpd.c,v 1.126 2002/05/26 09:32:07 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. All advertising materials mentioning features or use of this software 46 * must display the following acknowledgement: 47 * This product includes software developed by the University of 48 * California, Berkeley and its contributors. 49 * 4. Neither the name of the University nor the names of its contributors 50 * may be used to endorse or promote products derived from this software 51 * without specific prior written permission. 52 * 53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 56 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 63 * SUCH DAMAGE. 64 */ 65 66#ifndef lint 67static char copyright[] = 68"@(#) Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994\n\ 69 The Regents of the University of California. All rights reserved.\n"; 70#endif /* not lint */ 71 72#ifndef lint 73#if 0 74static char sccsid[] = "@(#)ftpd.c 8.4 (Berkeley) 4/16/94"; 75#else 76static char rcsid[] = "$OpenBSD: ftpd.c,v 1.126 2002/05/26 09:32:07 deraadt Exp $"; 77#endif 78#endif /* not lint */ 79 80/* 81 * FTP server. 82 */ 83#include <sys/param.h> 84#include <sys/stat.h> 85#include <sys/ioctl.h> 86#include <sys/socket.h> 87#include <sys/wait.h> 88#include <sys/mman.h> 89 90#include <netinet/in.h> 91#include <netinet/in_systm.h> 92#include <netinet/ip.h> 93#include <netinet/tcp.h> 94 95#define FTP_NAMES 96#include <arpa/ftp.h> 97#include <arpa/inet.h> 98#include <arpa/telnet.h> 99 100#include <bsd_auth.h> 101#include <ctype.h> 102#include <dirent.h> 103#include <err.h> 104#include <errno.h> 105#include <fcntl.h> 106#include <glob.h> 107#include <limits.h> 108#include <login_cap.h> 109#include <netdb.h> 110#include <pwd.h> 111#include <signal.h> 112#include <stdarg.h> 113#include <stdio.h> 114#include <stdlib.h> 115#include <string.h> 116#include <syslog.h> 117#include <time.h> 118#include <vis.h> 119#include <unistd.h> 120#include <util.h> 121#include <utmp.h> 122 123#if defined(TCPWRAPPERS) 124#include <tcpd.h> 125#endif /* TCPWRAPPERS */ 126 127#include "pathnames.h" 128#include "extern.h" 129 130static char version[] = "Version 6.5/OpenBSD"; 131 132extern off_t restart_point; 133extern char cbuf[]; 134 135union sockunion server_addr; 136union sockunion ctrl_addr; 137union sockunion data_source; 138union sockunion data_dest; 139union sockunion his_addr; 140union sockunion pasv_addr; 141 142sigset_t allsigs; 143 144int daemon_mode = 0; 145int data; 146int logged_in; 147struct passwd *pw; 148int debug = 0; 149int timeout = 900; /* timeout after 15 minutes of inactivity */ 150int maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */ 151int logging; 152int high_data_ports = 0; 153int anon_only = 0; 154int multihome = 0; 155int guest; 156int stats; 157int statfd = -1; 158int portcheck = 1; 159int dochroot; 160int type; 161int form; 162int stru; /* avoid C keyword */ 163int mode; 164int doutmp = 0; /* update utmp file */ 165int usedefault = 1; /* for data transfers */ 166int pdata = -1; /* for passive mode */ 167int family = AF_INET; 168volatile sig_atomic_t transflag; 169off_t file_size; 170off_t byte_count; 171#if !defined(CMASK) || CMASK == 0 172#undef CMASK 173#define CMASK 022 174#endif 175int defumask = CMASK; /* default umask value */ 176int umaskchange = 1; /* allow user to change umask value. */ 177char tmpline[7]; 178char hostname[MAXHOSTNAMELEN]; 179char remotehost[MAXHOSTNAMELEN]; 180char dhostname[MAXHOSTNAMELEN]; 181char *guestpw; 182static char ttyline[20]; 183char *tty = ttyline; /* for klogin */ 184static struct utmp utmp; /* for utmp */ 185static login_cap_t *lc; 186static auth_session_t *as; 187static volatile sig_atomic_t recvurg; 188 189#if defined(TCPWRAPPERS) 190int allow_severity = LOG_INFO; 191int deny_severity = LOG_NOTICE; 192#endif /* TCPWRAPPERS */ 193 194char *ident = NULL; 195 196 197int epsvall = 0; 198 199/* 200 * Timeout intervals for retrying connections 201 * to hosts that don't accept PORT cmds. This 202 * is a kludge, but given the problems with TCP... 203 */ 204#define SWAITMAX 90 /* wait at most 90 seconds */ 205#define SWAITINT 5 /* interval between retries */ 206 207int swaitmax = SWAITMAX; 208int swaitint = SWAITINT; 209 210#ifdef HASSETPROCTITLE 211char proctitle[BUFSIZ]; /* initial part of title */ 212#endif /* HASSETPROCTITLE */ 213 214#define LOGCMD(cmd, file) \ 215 if (logging > 1) \ 216 syslog(LOG_INFO,"%s %s%s", cmd, \ 217 *(file) == '/' ? "" : curdir(), file); 218#define LOGCMD2(cmd, file1, file2) \ 219 if (logging > 1) \ 220 syslog(LOG_INFO,"%s %s%s %s%s", cmd, \ 221 *(file1) == '/' ? "" : curdir(), file1, \ 222 *(file2) == '/' ? "" : curdir(), file2); 223#define LOGBYTES(cmd, file, cnt) \ 224 if (logging > 1) { \ 225 if (cnt == (off_t)-1) \ 226 syslog(LOG_INFO,"%s %s%s", cmd, \ 227 *(file) == '/' ? "" : curdir(), file); \ 228 else \ 229 syslog(LOG_INFO, "%s %s%s = %qd bytes", \ 230 cmd, (*(file) == '/') ? "" : curdir(), file, cnt); \ 231 } 232 233static void ack(char *); 234static void sigurg(int); 235static void myoob(void); 236static int checkuser(char *, char *); 237static FILE *dataconn(char *, off_t, char *); 238static void dolog(struct sockaddr *); 239static char *copy_dir(char *, struct passwd *); 240static char *curdir(void); 241static void end_login(void); 242static FILE *getdatasock(char *); 243static int guniquefd(char *, char **); 244static void lostconn(int); 245static void sigquit(int); 246static int receive_data(FILE *, FILE *); 247static void replydirname(const char *, const char *); 248static int send_data(FILE *, FILE *, off_t, off_t, int); 249static struct passwd * 250 sgetpwnam(char *); 251static void reapchild(int); 252static int check_host(struct sockaddr *); 253static void usage(void); 254 255void logxfer(char *, off_t, time_t); 256 257static char * 258curdir() 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 strcat(path, "/"); 266 /* For guest account, skip / since it's chrooted */ 267 return (guest ? path+1 : path); 268} 269 270char *argstr = "AdDhlMSt:T:u:UvP46"; 271 272static void 273usage() 274{ 275 syslog(LOG_ERR, 276 "usage: ftpd [-AdDhlMPSU46] [-t timeout] [-T maxtimeout] [-u mask]"); 277 exit(2); 278} 279 280int 281main(argc, argv, envp) 282 int argc; 283 char *argv[]; 284 char **envp; 285{ 286 int addrlen, ch, on = 1, tos; 287 char *cp, line[LINE_MAX]; 288 FILE *fp; 289 struct hostent *hp; 290 struct sigaction sa; 291 292 tzset(); /* in case no timezone database in ~ftp */ 293 sigfillset(&allsigs); /* used to block signals while root */ 294 sigemptyset(&sa.sa_mask); 295 sa.sa_flags = SA_RESTART; 296 297 while ((ch = getopt(argc, argv, argstr)) != -1) { 298 switch (ch) { 299 case 'A': 300 anon_only = 1; 301 break; 302 303 case 'd': 304 case 'v': /* deprecated */ 305 debug = 1; 306 break; 307 308 case 'D': 309 daemon_mode = 1; 310 break; 311 312 case 'P': 313 portcheck = 0; 314 break; 315 316 case 'h': 317 high_data_ports = 1; 318 break; 319 320 case 'l': 321 logging++; /* > 1 == extra logging */ 322 break; 323 324 case 'M': 325 multihome = 1; 326 break; 327 328 case 'S': 329 stats = 1; 330 break; 331 332 case 't': 333 timeout = atoi(optarg); 334 if (maxtimeout < timeout) 335 maxtimeout = timeout; 336 break; 337 338 case 'T': 339 maxtimeout = atoi(optarg); 340 if (timeout > maxtimeout) 341 timeout = maxtimeout; 342 break; 343 344 case 'u': 345 { 346 long val = 0; 347 char *p; 348 umaskchange = 0; 349 350 val = strtol(optarg, &p, 8); 351 if (*p != '\0' || val < 0 || (val & ~ACCESSPERMS)) { 352 syslog(LOG_ERR, 353 "ftpd: %s is a bad value for -u, aborting..", 354 optarg); 355 exit(2); 356 } else 357 defumask = val; 358 break; 359 } 360 361 case 'U': 362 doutmp = 1; 363 break; 364 365 case '4': 366 family = AF_INET; 367 break; 368 369 case '6': 370 family = AF_INET6; 371 break; 372 373 default: 374 usage(); 375 break; 376 } 377 } 378 379 (void) freopen(_PATH_DEVNULL, "w", stderr); 380 381 /* 382 * LOG_NDELAY sets up the logging connection immediately, 383 * necessary for anonymous ftp's that chroot and can't do it later. 384 */ 385 openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP); 386 387 if (daemon_mode) { 388 int ctl_sock, fd; 389 struct servent *sv; 390 391 /* 392 * Detach from parent. 393 */ 394 if (daemon(1, 1) < 0) { 395 syslog(LOG_ERR, "failed to become a daemon"); 396 exit(1); 397 } 398 sa.sa_handler = reapchild; 399 (void) sigaction(SIGCHLD, &sa, NULL); 400 /* 401 * Get port number for ftp/tcp. 402 */ 403 sv = getservbyname("ftp", "tcp"); 404 if (sv == NULL) { 405 syslog(LOG_ERR, "getservbyname for ftp failed"); 406 exit(1); 407 } 408 /* 409 * Open a socket, bind it to the FTP port, and start 410 * listening. 411 */ 412 ctl_sock = socket(family, SOCK_STREAM, 0); 413 if (ctl_sock < 0) { 414 syslog(LOG_ERR, "control socket: %m"); 415 exit(1); 416 } 417 if (setsockopt(ctl_sock, SOL_SOCKET, SO_REUSEADDR, 418 (char *)&on, sizeof(on)) < 0) 419 syslog(LOG_ERR, "control setsockopt: %m"); 420 memset(&server_addr, 0, sizeof(server_addr)); 421 server_addr.su_sin.sin_family = family; 422 switch (family) { 423 case AF_INET: 424 server_addr.su_len = sizeof(struct sockaddr_in); 425 server_addr.su_sin.sin_port = sv->s_port; 426 break; 427 case AF_INET6: 428 server_addr.su_len = sizeof(struct sockaddr_in6); 429 server_addr.su_sin6.sin6_port = sv->s_port; 430 break; 431 } 432 if (bind(ctl_sock, (struct sockaddr *)&server_addr, 433 server_addr.su_len)) { 434 syslog(LOG_ERR, "control bind: %m"); 435 exit(1); 436 } 437 if (listen(ctl_sock, 32) < 0) { 438 syslog(LOG_ERR, "control listen: %m"); 439 exit(1); 440 } 441 /* Stash pid in pidfile */ 442 if (pidfile(NULL)) 443 syslog(LOG_ERR, "can't open pidfile: %m"); 444 /* 445 * Loop forever accepting connection requests and forking off 446 * children to handle them. 447 */ 448 while (1) { 449 addrlen = sizeof(his_addr); 450 fd = accept(ctl_sock, (struct sockaddr *)&his_addr, 451 &addrlen); 452 if (fork() == 0) { 453 /* child */ 454 (void) dup2(fd, 0); 455 (void) dup2(fd, 1); 456 close(ctl_sock); 457 break; 458 } 459 close(fd); 460 } 461 462#if defined(TCPWRAPPERS) 463 /* ..in the child. */ 464 if (!check_host((struct sockaddr *)&his_addr)) 465 exit(1); 466#endif /* TCPWRAPPERS */ 467 } else { 468 addrlen = sizeof(his_addr); 469 if (getpeername(0, (struct sockaddr *)&his_addr, 470 &addrlen) < 0) { 471 /* syslog(LOG_ERR, "getpeername (%s): %m", argv[0]); */ 472 exit(1); 473 } 474 } 475 476 /* set this here so klogin can use it... */ 477 (void)snprintf(ttyline, sizeof(ttyline), "ftp%ld", (long)getpid()); 478 479 sa.sa_handler = SIG_DFL; 480 (void) sigaction(SIGCHLD, &sa, NULL); 481 482 sa.sa_handler = sigurg; 483 sa.sa_flags = 0; /* don't restart syscalls for SIGURG */ 484 (void) sigaction(SIGURG, &sa, NULL); 485 486 sigfillset(&sa.sa_mask); /* block all signals in handler */ 487 sa.sa_flags = SA_RESTART; 488 sa.sa_handler = sigquit; 489 (void) sigaction(SIGHUP, &sa, NULL); 490 (void) sigaction(SIGINT, &sa, NULL); 491 (void) sigaction(SIGQUIT, &sa, NULL); 492 (void) sigaction(SIGTERM, &sa, NULL); 493 494 sa.sa_handler = lostconn; 495 (void) sigaction(SIGPIPE, &sa, NULL); 496 497 addrlen = sizeof(ctrl_addr); 498 if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) { 499 syslog(LOG_ERR, "getsockname: %m"); 500 exit(1); 501 } 502 if (his_addr.su_family == AF_INET6 503 && IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr)) { 504#if 1 505 /* 506 * IPv4 control connection arrived to AF_INET6 socket. 507 * I hate to do this, but this is the easiest solution. 508 */ 509 union sockunion tmp_addr; 510 const int off = sizeof(struct in6_addr) - sizeof(struct in_addr); 511 512 tmp_addr = his_addr; 513 memset(&his_addr, 0, sizeof(his_addr)); 514 his_addr.su_sin.sin_family = AF_INET; 515 his_addr.su_sin.sin_len = sizeof(his_addr.su_sin); 516 memcpy(&his_addr.su_sin.sin_addr, 517 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 518 sizeof(his_addr.su_sin.sin_addr)); 519 his_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 520 521 tmp_addr = ctrl_addr; 522 memset(&ctrl_addr, 0, sizeof(ctrl_addr)); 523 ctrl_addr.su_sin.sin_family = AF_INET; 524 ctrl_addr.su_sin.sin_len = sizeof(ctrl_addr.su_sin); 525 memcpy(&ctrl_addr.su_sin.sin_addr, 526 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 527 sizeof(ctrl_addr.su_sin.sin_addr)); 528 ctrl_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 529#else 530 while (fgets(line, sizeof(line), fd) != NULL) { 531 if ((cp = strchr(line, '\n')) != NULL) 532 *cp = '\0'; 533 lreply(530, "%s", line); 534 } 535 (void) fflush(stdout); 536 (void) fclose(fd); 537 reply(530, 538 "Connection from IPv4 mapped address is not supported."); 539 exit(0); 540#endif 541 } 542#ifdef IP_TOS 543 if (his_addr.su_family == AF_INET) { 544 tos = IPTOS_LOWDELAY; 545 if (setsockopt(0, IPPROTO_IP, IP_TOS, (char *)&tos, 546 sizeof(int)) < 0) 547 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 548 } 549#endif 550 data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1); 551 552 /* Try to handle urgent data inline */ 553#ifdef SO_OOBINLINE 554 if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, (char *)&on, sizeof(on)) < 0) 555 syslog(LOG_ERR, "setsockopt: %m"); 556#endif 557 558#ifdef F_SETOWN 559 if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1) 560 syslog(LOG_ERR, "fcntl F_SETOWN: %m"); 561#endif 562 dolog((struct sockaddr *)&his_addr); 563 /* 564 * Set up default state 565 */ 566 data = -1; 567 type = TYPE_A; 568 form = FORM_N; 569 stru = STRU_F; 570 mode = MODE_S; 571 tmpline[0] = '\0'; 572 573 /* If logins are disabled, print out the message. */ 574 if ((fp = fopen(_PATH_NOLOGIN, "r")) != NULL) { 575 while (fgets(line, sizeof(line), fp) != NULL) { 576 if ((cp = strchr(line, '\n')) != NULL) 577 *cp = '\0'; 578 lreply(530, "%s", line); 579 } 580 (void) fflush(stdout); 581 (void) fclose(fp); 582 reply(530, "System not available."); 583 exit(0); 584 } 585 if ((fp = fopen(_PATH_FTPWELCOME, "r")) != NULL) { 586 while (fgets(line, sizeof(line), fp) != NULL) { 587 if ((cp = strchr(line, '\n')) != NULL) 588 *cp = '\0'; 589 lreply(220, "%s", line); 590 } 591 (void) fflush(stdout); 592 (void) fclose(fp); 593 /* reply(220,) must follow */ 594 } 595 (void) gethostname(hostname, sizeof(hostname)); 596 597 /* Make sure hostname is fully qualified. */ 598 hp = gethostbyname(hostname); 599 if (hp != NULL) 600 strlcpy(hostname, hp->h_name, sizeof(hostname)); 601 602 if (multihome) { 603 getnameinfo((struct sockaddr *)&ctrl_addr, ctrl_addr.su_len, 604 dhostname, sizeof(dhostname), NULL, 0, 0); 605 } 606 607 reply(220, "%s FTP server (%s) ready.", 608 (multihome ? dhostname : hostname), version); 609 for (;;) 610 (void) yyparse(); 611 /* NOTREACHED */ 612} 613 614/* 615 * Signal handlers. 616 */ 617 618static void 619lostconn(signo) 620 int signo; 621{ 622 struct syslog_data sdata = SYSLOG_DATA_INIT; 623 624 if (debug) 625 syslog_r(LOG_DEBUG, &sdata, "lost connection"); 626 dologout(1); 627} 628 629static void 630sigquit(signo) 631 int signo; 632{ 633 struct syslog_data sdata = SYSLOG_DATA_INIT; 634 635 syslog_r(LOG_ERR, &sdata, "got signal %s", sys_signame[signo]); 636 dologout(1); 637} 638 639/* 640 * Save the result of a getpwnam. Used for USER command, since 641 * the data returned must not be clobbered by any other command 642 * (e.g., globbing). 643 */ 644static struct passwd * 645sgetpwnam(name) 646 char *name; 647{ 648 static struct passwd *save; 649 struct passwd *pw; 650 651 if ((pw = getpwnam(name)) == NULL) 652 return (NULL); 653 if (save) { 654 memset(save->pw_passwd, 0, strlen(save->pw_passwd)); 655 free(save); 656 } 657 save = pw_dup(pw); 658 if (save == NULL) { 659 perror_reply(421, "Local resource failure: malloc"); 660 dologout(1); 661 /* NOTREACHED */ 662 } 663 return (save); 664} 665 666static int login_attempts; /* number of failed login attempts */ 667static int askpasswd; /* had user command, ask for passwd */ 668static char curname[MAXLOGNAME]; /* current USER name */ 669 670/* 671 * USER command. 672 * Sets global passwd pointer pw if named account exists and is acceptable; 673 * sets askpasswd if a PASS command is expected. If logged in previously, 674 * need to reset state. If name is "ftp" or "anonymous", the name is not in 675 * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return. 676 * If account doesn't exist, ask for passwd anyway. Otherwise, check user 677 * requesting login privileges. Disallow anyone who does not have a standard 678 * shell as returned by getusershell(). Disallow anyone mentioned in the file 679 * _PATH_FTPUSERS to allow people such as root and uucp to be avoided. 680 */ 681void 682user(name) 683 char *name; 684{ 685 char *cp, *shell, *style, *host; 686 char *class = NULL; 687 688 if (logged_in) { 689 if (guest) { 690 reply(530, "Can't change user from guest login."); 691 return; 692 } else if (dochroot) { 693 reply(530, "Can't change user from chroot user."); 694 return; 695 } 696 end_login(); 697 } 698 699 /* Close session from previous user if there was one. */ 700 if (as) { 701 auth_close(as); 702 as = NULL; 703 } 704 if (lc) { 705 login_close(lc); 706 lc = NULL; 707 } 708 709 if ((style = strchr(name, ':')) != NULL) 710 *style++ = 0; 711 712 guest = 0; 713 host = multihome ? dhostname : hostname; 714 if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) { 715 if (checkuser(_PATH_FTPUSERS, "ftp") || 716 checkuser(_PATH_FTPUSERS, "anonymous")) 717 reply(530, "User %s access denied.", name); 718 else if ((pw = sgetpwnam("ftp")) != NULL) { 719 guest = 1; 720 askpasswd = 1; 721 lc = login_getclass(pw->pw_class); 722 if ((as = auth_open()) == NULL || 723 auth_setpwd(as, pw) != 0 || 724 auth_setoption(as, "FTPD_HOST", host) < 0) { 725 if (as) { 726 auth_close(as); 727 as = NULL; 728 } 729 login_close(lc); 730 lc = NULL; 731 reply(421, "Local resource failure"); 732 return; 733 } 734 reply(331, 735 "Guest login ok, send your email address as password."); 736 } else 737 reply(530, "User %s unknown.", name); 738 if (!askpasswd && logging) 739 syslog(LOG_NOTICE, 740 "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost); 741 return; 742 } 743 744 shell = _PATH_BSHELL; 745 if ((pw = sgetpwnam(name))) { 746 class = pw->pw_class; 747 if (pw->pw_shell != NULL && *pw->pw_shell != '\0') 748 shell = pw->pw_shell; 749 while ((cp = getusershell()) != NULL) 750 if (strcmp(cp, shell) == 0) 751 break; 752 shell = cp; 753 endusershell(); 754 } 755 756 /* Get login class; if invalid style treat like unknown user. */ 757 lc = login_getclass(class); 758 if (lc && (style = login_getstyle(lc, style, "auth-ftp")) == NULL) { 759 login_close(lc); 760 lc = NULL; 761 pw = NULL; 762 } 763 764 /* Do pre-authentication setup. */ 765 if (lc && ((as = auth_open()) == NULL || 766 (pw != NULL && auth_setpwd(as, pw) != 0) || 767 auth_setitem(as, AUTHV_STYLE, style) < 0 || 768 auth_setitem(as, AUTHV_NAME, name) < 0 || 769 auth_setitem(as, AUTHV_CLASS, class) < 0 || 770 auth_setoption(as, "login", "yes") < 0 || 771 auth_setoption(as, "notickets", "yes") < 0 || 772 auth_setoption(as, "FTPD_HOST", host) < 0)) { 773 if (as) { 774 auth_close(as); 775 as = NULL; 776 } 777 login_close(lc); 778 lc = NULL; 779 reply(421, "Local resource failure"); 780 return; 781 } 782 if (logging) 783 strlcpy(curname, name, sizeof(curname)); 784 785 dochroot = (lc && login_getcapbool(lc, "ftp-chroot", 0)) || 786 checkuser(_PATH_FTPCHROOT, name); 787 if (anon_only && !dochroot) { 788 reply(530, "Sorry, only anonymous ftp allowed."); 789 return; 790 } 791 if (pw) { 792 if ((!shell && !dochroot) || checkuser(_PATH_FTPUSERS, name)) { 793 reply(530, "User %s access denied.", name); 794 if (logging) 795 syslog(LOG_NOTICE, 796 "FTP LOGIN REFUSED FROM %s, %s", 797 remotehost, name); 798 pw = NULL; 799 return; 800 } 801 } 802 803 if (as != NULL && (cp = auth_challenge(as)) != NULL) 804 reply(331, cp); 805 else 806 reply(331, "Password required for %s.", name); 807 808 askpasswd = 1; 809 /* 810 * Delay before reading passwd after first failed 811 * attempt to slow down passwd-guessing programs. 812 */ 813 if (login_attempts) 814 sleep((unsigned) login_attempts); 815} 816 817/* 818 * Check if a user is in the file "fname" 819 */ 820static int 821checkuser(fname, name) 822 char *fname; 823 char *name; 824{ 825 FILE *fp; 826 int found = 0; 827 char *p, line[BUFSIZ]; 828 829 if ((fp = fopen(fname, "r")) != NULL) { 830 while (fgets(line, sizeof(line), fp) != NULL) 831 if ((p = strchr(line, '\n')) != NULL) { 832 *p = '\0'; 833 if (line[0] == '#') 834 continue; 835 if (strcmp(line, name) == 0) { 836 found = 1; 837 break; 838 } 839 } 840 (void) fclose(fp); 841 } 842 return (found); 843} 844 845/* 846 * Terminate login as previous user, if any, resetting state; 847 * used when USER command is given or login fails. 848 */ 849static void 850end_login() 851{ 852 853 sigprocmask (SIG_BLOCK, &allsigs, NULL); 854 (void) seteuid((uid_t)0); 855 if (logged_in) { 856 ftpdlogwtmp(ttyline, "", ""); 857 if (doutmp) 858 logout(utmp.ut_line); 859 } 860 pw = NULL; 861 /* umask is restored in ftpcmd.y */ 862 setusercontext(NULL, getpwuid(0), (uid_t)0, 863 LOGIN_SETPRIORITY|LOGIN_SETRESOURCES); 864 logged_in = 0; 865 guest = 0; 866 dochroot = 0; 867} 868 869void 870pass(passwd) 871 char *passwd; 872{ 873 int authok, flags; 874 FILE *fp; 875 static char homedir[MAXPATHLEN]; 876 char *motd, *dir, rootdir[MAXPATHLEN]; 877 878 if (logged_in || askpasswd == 0) { 879 reply(503, "Login with USER first."); 880 return; 881 } 882 askpasswd = 0; 883 if (!guest) { /* "ftp" is only account allowed no password */ 884 authok = 0; 885 if (pw == NULL || pw->pw_passwd[0] == '\0') { 886 useconds_t us; 887 888 /* Sleep between 1 and 3 seconds to emulate a crypt. */ 889 us = arc4random() % 3000000; 890 usleep(us); 891 if (as != NULL) { 892 auth_close(as); 893 as = NULL; 894 } 895 } else { 896 authok = auth_userresponse(as, passwd, 0); 897 as = NULL; 898 } 899 if (authok == 0) { 900 reply(530, "Login incorrect."); 901 if (logging) 902 syslog(LOG_NOTICE, 903 "FTP LOGIN FAILED FROM %s, %s", 904 remotehost, curname); 905 pw = NULL; 906 if (login_attempts++ >= 5) { 907 syslog(LOG_NOTICE, 908 "repeated login failures from %s", 909 remotehost); 910 exit(0); 911 } 912 return; 913 } 914 } else if (lc != NULL) { 915 /* Save anonymous' password. */ 916 if (guestpw != NULL) 917 free(guestpw); 918 guestpw = strdup(passwd); 919 if (guestpw == NULL) 920 fatal("Out of memory."); 921 922 authok = auth_approval(as, lc, pw->pw_name, "ftp"); 923 auth_close(as); 924 as = NULL; 925 if (authok == 0) { 926 syslog(LOG_INFO|LOG_AUTH, 927 "FTP LOGIN FAILED (HOST) as %s: approval failure.", 928 pw->pw_name); 929 reply(530, "Approval failure."); 930 exit(0); 931 } 932 } else { 933 syslog(LOG_INFO|LOG_AUTH, 934 "FTP LOGIN CLASS %s MISSING for %s: approval failure.", 935 pw->pw_class, pw->pw_name); 936 reply(530, "Permission denied."); 937 exit(0); 938 } 939 login_attempts = 0; /* this time successful */ 940 if (setegid((gid_t)pw->pw_gid) < 0) { 941 reply(550, "Can't set gid."); 942 return; 943 } 944 /* set umask via setusercontext() unless -u flag was given. */ 945 flags = LOGIN_SETGROUP|LOGIN_SETPRIORITY|LOGIN_SETRESOURCES; 946 if (umaskchange) 947 flags |= LOGIN_SETUMASK; 948 else 949 (void) umask(defumask); 950 setusercontext(lc, pw, (uid_t)0, flags); 951 952 /* open wtmp before chroot */ 953 ftpdlogwtmp(ttyline, pw->pw_name, remotehost); 954 955 /* open utmp before chroot */ 956 if (doutmp) { 957 memset((void *)&utmp, 0, sizeof(utmp)); 958 (void)time(&utmp.ut_time); 959 (void)strncpy(utmp.ut_name, pw->pw_name, sizeof(utmp.ut_name)); 960 (void)strncpy(utmp.ut_host, remotehost, sizeof(utmp.ut_host)); 961 (void)strncpy(utmp.ut_line, ttyline, sizeof(utmp.ut_line)); 962 login(&utmp); 963 } 964 965 /* open stats file before chroot */ 966 if (guest && (stats == 1) && (statfd < 0)) 967 if ((statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND)) < 0) 968 stats = 0; 969 970 logged_in = 1; 971 972 if ((dir = login_getcapstr(lc, "ftp-dir", NULL, NULL))) { 973 char *newdir; 974 975 newdir = copy_dir(dir, pw); 976 if (newdir == NULL) { 977 perror_reply(421, "Local resource failure: malloc"); 978 dologout(1); 979 /* NOTREACHED */ 980 } 981 free(dir); 982 free(pw->pw_dir); 983 pw->pw_dir = newdir; 984 } 985 986 /* make sure pw->pw_dir is big enough to hold "/" */ 987 if (strlen(pw->pw_dir) < 1) { 988 char *newdir; 989 990 newdir = malloc(2); 991 if (newdir == NULL) { 992 perror_reply(421, "Local resource failure: malloc"); 993 dologout(1); 994 /* NOTREACHED */ 995 } 996 strlcpy(newdir, pw->pw_dir, 2); 997 free(pw->pw_dir); 998 pw->pw_dir = newdir; 999 } 1000 1001 if (guest || dochroot) { 1002 if (multihome && guest) { 1003 struct stat ts; 1004 1005 /* Compute root directory. */ 1006 snprintf(rootdir, sizeof(rootdir), "%s/%s", 1007 pw->pw_dir, dhostname); 1008 if (stat(rootdir, &ts) < 0) { 1009 snprintf(rootdir, sizeof(rootdir), "%s/%s", 1010 pw->pw_dir, hostname); 1011 } 1012 } else 1013 strlcpy(rootdir, pw->pw_dir, sizeof(rootdir)); 1014 } 1015 if (guest) { 1016 /* 1017 * We MUST do a chdir() after the chroot. Otherwise 1018 * the old current directory will be accessible as "." 1019 * outside the new root! 1020 */ 1021 if (chroot(rootdir) < 0 || chdir("/") < 0) { 1022 reply(550, "Can't set guest privileges."); 1023 goto bad; 1024 } 1025 strcpy(pw->pw_dir, "/"); 1026 if (setenv("HOME", "/", 1) == -1) { 1027 reply(550, "Can't setup environment."); 1028 goto bad; 1029 } 1030 } else if (dochroot) { 1031 if (chroot(rootdir) < 0 || chdir("/") < 0) { 1032 reply(550, "Can't change root."); 1033 goto bad; 1034 } 1035 strcpy(pw->pw_dir, "/"); 1036 if (setenv("HOME", "/", 1) == -1) { 1037 reply(550, "Can't setup environment."); 1038 goto bad; 1039 } 1040 } else if (chdir(pw->pw_dir) < 0) { 1041 if (chdir("/") < 0) { 1042 reply(530, "User %s: can't change directory to %s.", 1043 pw->pw_name, pw->pw_dir); 1044 goto bad; 1045 } else 1046 lreply(230, "No directory! Logging in with home=/"); 1047 } 1048 if (seteuid((uid_t)pw->pw_uid) < 0) { 1049 reply(550, "Can't set uid."); 1050 goto bad; 1051 } 1052 sigprocmask(SIG_UNBLOCK, &allsigs, NULL); 1053 1054 /* 1055 * Set home directory so that use of ~ (tilde) works correctly. 1056 */ 1057 if (getcwd(homedir, MAXPATHLEN) != NULL) { 1058 if (setenv("HOME", homedir, 1) == -1) { 1059 reply(550, "Can't setup environment."); 1060 goto bad; 1061 } 1062 } 1063 1064 /* 1065 * Display a login message, if it exists. 1066 * N.B. reply(230,) must follow the message. 1067 */ 1068 motd = login_getcapstr(lc, "welcome", NULL, NULL); 1069 if ((fp = fopen(motd ? motd : _PATH_FTPLOGINMESG, "r")) != NULL) { 1070 char *cp, line[LINE_MAX]; 1071 1072 while (fgets(line, sizeof(line), fp) != NULL) { 1073 if ((cp = strchr(line, '\n')) != NULL) 1074 *cp = '\0'; 1075 lreply(230, "%s", line); 1076 } 1077 (void) fflush(stdout); 1078 (void) fclose(fp); 1079 } 1080 if (motd != NULL) 1081 free(motd); 1082 if (guest) { 1083 if (ident != NULL) 1084 free(ident); 1085 ident = strdup(passwd); 1086 if (ident == NULL) 1087 fatal("Ran out of memory."); 1088 reply(230, "Guest login ok, access restrictions apply."); 1089#ifdef HASSETPROCTITLE 1090 snprintf(proctitle, sizeof(proctitle), 1091 "%s: anonymous/%.*s", remotehost, 1092 (int)(sizeof(proctitle) - sizeof(remotehost) - 1093 sizeof(": anonymous/")), passwd); 1094 setproctitle("%s", proctitle); 1095#endif /* HASSETPROCTITLE */ 1096 if (logging) 1097 syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s", 1098 remotehost, passwd); 1099 } else { 1100 reply(230, "User %s logged in.", pw->pw_name); 1101#ifdef HASSETPROCTITLE 1102 snprintf(proctitle, sizeof(proctitle), 1103 "%s: %s", remotehost, pw->pw_name); 1104 setproctitle("%s", proctitle); 1105#endif /* HASSETPROCTITLE */ 1106 if (logging) 1107 syslog(LOG_INFO, "FTP LOGIN FROM %s as %s", 1108 remotehost, pw->pw_name); 1109 } 1110 login_close(lc); 1111 lc = NULL; 1112 return; 1113bad: 1114 /* Forget all about it... */ 1115 login_close(lc); 1116 lc = NULL; 1117 end_login(); 1118} 1119 1120void 1121retrieve(cmd, name) 1122 char *cmd, *name; 1123{ 1124 FILE *fin, *dout; 1125 struct stat st; 1126 int (*closefunc)(FILE *); 1127 time_t start; 1128 1129 if (cmd == 0) { 1130 fin = fopen(name, "r"), closefunc = fclose; 1131 st.st_size = 0; 1132 } else { 1133 char line[BUFSIZ]; 1134 1135 (void) snprintf(line, sizeof(line), cmd, name); 1136 name = line; 1137 fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose; 1138 st.st_size = -1; 1139 st.st_blksize = BUFSIZ; 1140 } 1141 if (fin == NULL) { 1142 if (errno != 0) { 1143 perror_reply(550, name); 1144 if (cmd == 0) { 1145 LOGCMD("get", name); 1146 } 1147 } 1148 return; 1149 } 1150 byte_count = -1; 1151 if (cmd == 0 && (fstat(fileno(fin), &st) < 0 || !S_ISREG(st.st_mode))) { 1152 reply(550, "%s: not a plain file.", name); 1153 goto done; 1154 } 1155 if (restart_point) { 1156 if (type == TYPE_A) { 1157 off_t i, n; 1158 int c; 1159 1160 n = restart_point; 1161 i = 0; 1162 while (i++ < n) { 1163 if ((c=getc(fin)) == EOF) { 1164 perror_reply(550, name); 1165 goto done; 1166 } 1167 if (c == '\n') 1168 i++; 1169 } 1170 } else if (lseek(fileno(fin), restart_point, SEEK_SET) < 0) { 1171 perror_reply(550, name); 1172 goto done; 1173 } 1174 } 1175 dout = dataconn(name, st.st_size, "w"); 1176 if (dout == NULL) 1177 goto done; 1178 time(&start); 1179 send_data(fin, dout, st.st_blksize, st.st_size, 1180 (restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode))); 1181 if ((cmd == 0) && stats) 1182 logxfer(name, byte_count, start); 1183 (void) fclose(dout); 1184 data = -1; 1185done: 1186 if (pdata >= 0) 1187 (void) close(pdata); 1188 pdata = -1; 1189 if (cmd == 0) 1190 LOGBYTES("get", name, byte_count); 1191 (*closefunc)(fin); 1192} 1193 1194void 1195store(name, mode, unique) 1196 char *name, *mode; 1197 int unique; 1198{ 1199 FILE *fout, *din; 1200 int (*closefunc)(FILE *); 1201 struct stat st; 1202 int fd; 1203 1204 if (restart_point && *mode != 'a') 1205 mode = "r+"; 1206 1207 if (unique && stat(name, &st) == 0) { 1208 char *nam; 1209 1210 fd = guniquefd(name, &nam); 1211 if (fd == -1) { 1212 LOGCMD(*mode == 'w' ? "put" : "append", name); 1213 return; 1214 } 1215 name = nam; 1216 fout = fdopen(fd, mode); 1217 } else 1218 fout = fopen(name, mode); 1219 1220 closefunc = fclose; 1221 if (fout == NULL) { 1222 perror_reply(553, name); 1223 LOGCMD(*mode == 'w' ? "put" : "append", name); 1224 return; 1225 } 1226 byte_count = -1; 1227 if (restart_point) { 1228 if (type == TYPE_A) { 1229 off_t i, n; 1230 int c; 1231 1232 n = restart_point; 1233 i = 0; 1234 while (i++ < n) { 1235 if ((c=getc(fout)) == EOF) { 1236 perror_reply(550, name); 1237 goto done; 1238 } 1239 if (c == '\n') 1240 i++; 1241 } 1242 /* 1243 * We must do this seek to "current" position 1244 * because we are changing from reading to 1245 * writing. 1246 */ 1247 if (fseek(fout, 0L, SEEK_CUR) < 0) { 1248 perror_reply(550, name); 1249 goto done; 1250 } 1251 } else if (lseek(fileno(fout), restart_point, SEEK_SET) < 0) { 1252 perror_reply(550, name); 1253 goto done; 1254 } 1255 } 1256 din = dataconn(name, (off_t)-1, "r"); 1257 if (din == NULL) 1258 goto done; 1259 if (receive_data(din, fout) == 0) { 1260 if (unique) 1261 reply(226, "Transfer complete (unique file name:%s).", 1262 name); 1263 else 1264 reply(226, "Transfer complete."); 1265 } 1266 (void) fclose(din); 1267 data = -1; 1268 pdata = -1; 1269done: 1270 LOGBYTES(*mode == 'w' ? "put" : "append", name, byte_count); 1271 (*closefunc)(fout); 1272} 1273 1274static FILE * 1275getdatasock(mode) 1276 char *mode; 1277{ 1278 int on = 1, s, t, tries; 1279 1280 if (data >= 0) 1281 return (fdopen(data, mode)); 1282 sigprocmask (SIG_BLOCK, &allsigs, NULL); 1283 (void) seteuid((uid_t)0); 1284 s = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 1285 if (s < 0) 1286 goto bad; 1287 if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, 1288 (char *) &on, sizeof(on)) < 0) 1289 goto bad; 1290 /* anchor socket to avoid multi-homing problems */ 1291 data_source = ctrl_addr; 1292 data_source.su_port = htons(20); /* ftp-data port */ 1293 for (tries = 1; ; tries++) { 1294 if (bind(s, (struct sockaddr *)&data_source, 1295 data_source.su_len) >= 0) 1296 break; 1297 if (errno != EADDRINUSE || tries > 10) 1298 goto bad; 1299 sleep(tries); 1300 } 1301 (void) seteuid((uid_t)pw->pw_uid); 1302 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1303 1304#ifdef IP_TOS 1305 if (ctrl_addr.su_family == AF_INET) { 1306 on = IPTOS_THROUGHPUT; 1307 if (setsockopt(s, IPPROTO_IP, IP_TOS, (char *)&on, 1308 sizeof(int)) < 0) 1309 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 1310 } 1311#endif 1312#ifdef TCP_NOPUSH 1313 /* 1314 * Turn off push flag to keep sender TCP from sending short packets 1315 * at the boundaries of each write(). Should probably do a SO_SNDBUF 1316 * to set the send buffer size as well, but that may not be desirable 1317 * in heavy-load situations. 1318 */ 1319 on = 1; 1320 if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, (char *)&on, sizeof(on)) < 0) 1321 syslog(LOG_WARNING, "setsockopt (TCP_NOPUSH): %m"); 1322#endif 1323#ifdef SO_SNDBUF 1324 on = 65536; 1325 if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, (char *)&on, sizeof(on)) < 0) 1326 syslog(LOG_WARNING, "setsockopt (SO_SNDBUF): %m"); 1327#endif 1328 1329 return (fdopen(s, mode)); 1330bad: 1331 /* Return the real value of errno (close may change it) */ 1332 t = errno; 1333 (void) seteuid((uid_t)pw->pw_uid); 1334 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1335 (void) close(s); 1336 errno = t; 1337 return (NULL); 1338} 1339 1340static FILE * 1341dataconn(name, size, mode) 1342 char *name; 1343 off_t size; 1344 char *mode; 1345{ 1346 char sizebuf[32]; 1347 FILE *file; 1348 int retry = 0; 1349 in_port_t *p; 1350 char *fa, *ha; 1351 int alen; 1352 1353 file_size = size; 1354 byte_count = 0; 1355 if (size != (off_t) -1) { 1356 (void) snprintf(sizebuf, sizeof(sizebuf), " (%qd bytes)", 1357 size); 1358 } else 1359 sizebuf[0] = '\0'; 1360 if (pdata >= 0) { 1361 union sockunion from; 1362 int s, fromlen = sizeof(from); 1363 1364 signal (SIGALRM, toolong); 1365 (void) alarm ((unsigned) timeout); 1366 s = accept(pdata, (struct sockaddr *)&from, &fromlen); 1367 (void) alarm (0); 1368 if (s < 0) { 1369 reply(425, "Can't open data connection."); 1370 (void) close(pdata); 1371 pdata = -1; 1372 return (NULL); 1373 } 1374 switch (from.su_family) { 1375 case AF_INET: 1376 p = (in_port_t *)&from.su_sin.sin_port; 1377 fa = (u_char *)&from.su_sin.sin_addr; 1378 ha = (u_char *)&his_addr.su_sin.sin_addr; 1379 alen = sizeof(struct in_addr); 1380 break; 1381 case AF_INET6: 1382 p = (in_port_t *)&from.su_sin6.sin6_port; 1383 fa = (u_char *)&from.su_sin6.sin6_addr; 1384 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1385 alen = sizeof(struct in6_addr); 1386 break; 1387 default: 1388 perror_reply(425, "Can't build data connection"); 1389 (void) close(pdata); 1390 (void) close(s); 1391 pdata = -1; 1392 return (NULL); 1393 } 1394 if (from.su_family != his_addr.su_family || 1395 ntohs(*p) < IPPORT_RESERVED) { 1396 perror_reply(425, "Can't build data connection"); 1397 (void) close(pdata); 1398 (void) close(s); 1399 pdata = -1; 1400 return (NULL); 1401 } 1402 if (portcheck && memcmp(fa, ha, alen) != 0) { 1403 perror_reply(435, "Can't build data connection"); 1404 (void) close(pdata); 1405 (void) close(s); 1406 pdata = -1; 1407 return (NULL); 1408 } 1409 (void) close(pdata); 1410 pdata = s; 1411 reply(150, "Opening %s mode data connection for '%s'%s.", 1412 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1413 return (fdopen(pdata, mode)); 1414 } 1415 if (data >= 0) { 1416 reply(125, "Using existing data connection for '%s'%s.", 1417 name, sizebuf); 1418 usedefault = 1; 1419 return (fdopen(data, mode)); 1420 } 1421 if (usedefault) 1422 data_dest = his_addr; 1423 usedefault = 1; 1424 file = getdatasock(mode); 1425 if (file == NULL) { 1426 char hbuf[MAXHOSTNAMELEN], pbuf[10]; 1427 1428 getnameinfo((struct sockaddr *)&data_source, data_source.su_len, 1429 hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), 1430 NI_NUMERICHOST | NI_NUMERICSERV); 1431 reply(425, "Can't create data socket (%s,%s): %s.", 1432 hbuf, pbuf, strerror(errno)); 1433 return (NULL); 1434 } 1435 data = fileno(file); 1436 1437 /* 1438 * attempt to connect to reserved port on client machine; 1439 * this looks like an attack 1440 */ 1441 switch (data_dest.su_family) { 1442 case AF_INET: 1443 p = (in_port_t *)&data_dest.su_sin.sin_port; 1444 fa = (u_char *)&data_dest.su_sin.sin_addr; 1445 ha = (u_char *)&his_addr.su_sin.sin_addr; 1446 alen = sizeof(struct in_addr); 1447 break; 1448 case AF_INET6: 1449 p = (in_port_t *)&data_dest.su_sin6.sin6_port; 1450 fa = (u_char *)&data_dest.su_sin6.sin6_addr; 1451 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1452 alen = sizeof(struct in6_addr); 1453 break; 1454 default: 1455 perror_reply(425, "Can't build data connection"); 1456 (void) fclose(file); 1457 pdata = -1; 1458 return (NULL); 1459 } 1460 if (data_dest.su_family != his_addr.su_family || 1461 ntohs(*p) < IPPORT_RESERVED || ntohs(*p) == 2049) { /* XXX */ 1462 perror_reply(425, "Can't build data connection"); 1463 (void) fclose(file); 1464 data = -1; 1465 return NULL; 1466 } 1467 if (portcheck && memcmp(fa, ha, alen) != 0) { 1468 perror_reply(435, "Can't build data connection"); 1469 (void) fclose(file); 1470 data = -1; 1471 return NULL; 1472 } 1473 while (connect(data, (struct sockaddr *)&data_dest, 1474 data_dest.su_len) < 0) { 1475 if (errno == EADDRINUSE && retry < swaitmax) { 1476 sleep((unsigned) swaitint); 1477 retry += swaitint; 1478 continue; 1479 } 1480 perror_reply(425, "Can't build data connection"); 1481 (void) fclose(file); 1482 data = -1; 1483 return (NULL); 1484 } 1485 reply(150, "Opening %s mode data connection for '%s'%s.", 1486 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1487 return (file); 1488} 1489 1490/* 1491 * Tranfer the contents of "instr" to "outstr" peer using the appropriate 1492 * encapsulation of the data subject to Mode, Structure, and Type. 1493 * 1494 * NB: Form isn't handled. 1495 */ 1496static int 1497send_data(instr, outstr, blksize, filesize, isreg) 1498 FILE *instr, *outstr; 1499 off_t blksize; 1500 off_t filesize; 1501 int isreg; 1502{ 1503 int c, cnt, filefd, netfd; 1504 char *buf, *bp; 1505 size_t len; 1506 1507 transflag++; 1508 switch (type) { 1509 1510 case TYPE_A: 1511 while ((c = getc(instr)) != EOF) { 1512 if (recvurg) 1513 goto got_oob; 1514 byte_count++; 1515 if (c == '\n') { 1516 if (ferror(outstr)) 1517 goto data_err; 1518 (void) putc('\r', outstr); 1519 } 1520 (void) putc(c, outstr); 1521 } 1522 fflush(outstr); 1523 transflag = 0; 1524 if (ferror(instr)) 1525 goto file_err; 1526 if (ferror(outstr)) 1527 goto data_err; 1528 reply(226, "Transfer complete."); 1529 return(0); 1530 1531 case TYPE_I: 1532 case TYPE_L: 1533 /* 1534 * isreg is only set if we are not doing restart and we 1535 * are sending a regular file 1536 */ 1537 netfd = fileno(outstr); 1538 filefd = fileno(instr); 1539 1540 if (isreg && filesize < (off_t)16 * 1024 * 1024) { 1541 buf = mmap(0, filesize, PROT_READ, MAP_SHARED, filefd, 1542 (off_t)0); 1543 if (buf == MAP_FAILED) { 1544 syslog(LOG_WARNING, "mmap(%lu): %m", 1545 (unsigned long)filesize); 1546 goto oldway; 1547 } 1548 bp = buf; 1549 len = filesize; 1550 do { 1551 cnt = write(netfd, bp, len); 1552 if (recvurg) { 1553 munmap(buf, (size_t)filesize); 1554 goto got_oob; 1555 } 1556 len -= cnt; 1557 bp += cnt; 1558 if (cnt > 0) byte_count += cnt; 1559 } while(cnt > 0 && len > 0); 1560 1561 transflag = 0; 1562 munmap(buf, (size_t)filesize); 1563 if (cnt < 0) 1564 goto data_err; 1565 reply(226, "Transfer complete."); 1566 return(0); 1567 } 1568 1569oldway: 1570 if ((buf = malloc((u_int)blksize)) == NULL) { 1571 transflag = 0; 1572 perror_reply(451, "Local resource failure: malloc"); 1573 return(-1); 1574 } 1575 1576 while ((cnt = read(filefd, buf, (u_int)blksize)) > 0 && 1577 write(netfd, buf, cnt) == cnt) 1578 byte_count += cnt; 1579 transflag = 0; 1580 (void)free(buf); 1581 if (cnt != 0) { 1582 if (cnt < 0) 1583 goto file_err; 1584 goto data_err; 1585 } 1586 reply(226, "Transfer complete."); 1587 return(0); 1588 default: 1589 transflag = 0; 1590 reply(550, "Unimplemented TYPE %d in send_data", type); 1591 return(-1); 1592 } 1593 1594data_err: 1595 transflag = 0; 1596 perror_reply(426, "Data connection"); 1597 return(-1); 1598 1599file_err: 1600 transflag = 0; 1601 perror_reply(551, "Error on input file"); 1602 return(-1); 1603 1604got_oob: 1605 myoob(); 1606 recvurg = 0; 1607 transflag = 0; 1608 return(-1); 1609} 1610 1611/* 1612 * Transfer data from peer to "outstr" using the appropriate encapulation of 1613 * the data subject to Mode, Structure, and Type. 1614 * 1615 * N.B.: Form isn't handled. 1616 */ 1617static int 1618receive_data(instr, outstr) 1619 FILE *instr, *outstr; 1620{ 1621 int c; 1622 int cnt; 1623 char buf[BUFSIZ]; 1624 struct sigaction sa; 1625 volatile int bare_lfs = 0; 1626 1627 transflag++; 1628 switch (type) { 1629 1630 case TYPE_I: 1631 case TYPE_L: 1632 sigfillset(&sa.sa_mask); 1633 sa.sa_flags = SA_RESTART; 1634 sigaction(SIGALRM, &sa, NULL); 1635 1636 do { 1637 (void) alarm ((unsigned) timeout); 1638 cnt = read(fileno(instr), buf, sizeof(buf)); 1639 (void) alarm (0); 1640 if (recvurg) 1641 goto got_oob; 1642 1643 if (cnt > 0) { 1644 if (write(fileno(outstr), buf, cnt) != cnt) 1645 goto file_err; 1646 byte_count += cnt; 1647 } 1648 } while (cnt > 0); 1649 if (cnt < 0) 1650 goto data_err; 1651 transflag = 0; 1652 return (0); 1653 1654 case TYPE_E: 1655 reply(553, "TYPE E not implemented."); 1656 transflag = 0; 1657 return (-1); 1658 1659 case TYPE_A: 1660 while ((c = getc(instr)) != EOF) { 1661 if (recvurg) 1662 goto got_oob; 1663 byte_count++; 1664 if (c == '\n') 1665 bare_lfs++; 1666 while (c == '\r') { 1667 if (ferror(outstr)) 1668 goto data_err; 1669 if ((c = getc(instr)) != '\n') { 1670 (void) putc ('\r', outstr); 1671 if (c == '\0' || c == EOF) 1672 goto contin2; 1673 } 1674 } 1675 (void) putc(c, outstr); 1676 contin2: ; 1677 } 1678 fflush(outstr); 1679 if (ferror(instr)) 1680 goto data_err; 1681 if (ferror(outstr)) 1682 goto file_err; 1683 transflag = 0; 1684 if (bare_lfs) { 1685 lreply(226, 1686 "WARNING! %d bare linefeeds received in ASCII mode", 1687 bare_lfs); 1688 printf(" File may not have transferred correctly.\r\n"); 1689 } 1690 return (0); 1691 default: 1692 reply(550, "Unimplemented TYPE %d in receive_data", type); 1693 transflag = 0; 1694 return (-1); 1695 } 1696 1697data_err: 1698 transflag = 0; 1699 perror_reply(426, "Data Connection"); 1700 return (-1); 1701 1702file_err: 1703 transflag = 0; 1704 perror_reply(452, "Error writing file"); 1705 return (-1); 1706 1707got_oob: 1708 myoob(); 1709 recvurg = 0; 1710 transflag = 0; 1711 return (-1); 1712} 1713 1714void 1715statfilecmd(filename) 1716 char *filename; 1717{ 1718 FILE *fin; 1719 int c; 1720 int atstart; 1721 char line[LINE_MAX]; 1722 1723 (void)snprintf(line, sizeof(line), "/bin/ls -lgA %s", filename); 1724 fin = ftpd_popen(line, "r"); 1725 lreply(211, "status of %s:", filename); 1726 atstart = 1; 1727 while ((c = getc(fin)) != EOF) { 1728 if (c == '\n') { 1729 if (ferror(stdout)){ 1730 perror_reply(421, "control connection"); 1731 (void) ftpd_pclose(fin); 1732 dologout(1); 1733 /* NOTREACHED */ 1734 } 1735 if (ferror(fin)) { 1736 perror_reply(551, filename); 1737 (void) ftpd_pclose(fin); 1738 return; 1739 } 1740 (void) putc('\r', stdout); 1741 } 1742 if (atstart && isdigit(c)) 1743 (void) putc(' ', stdout); 1744 (void) putc(c, stdout); 1745 atstart = (c == '\n'); 1746 } 1747 (void) ftpd_pclose(fin); 1748 reply(211, "End of Status"); 1749} 1750 1751void 1752statcmd() 1753{ 1754 union sockunion *su; 1755 u_char *a, *p; 1756 char hbuf[MAXHOSTNAMELEN]; 1757 int ispassive; 1758 1759 lreply(211, "%s FTP server status:", hostname, version); 1760 printf(" %s\r\n", version); 1761 getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len, 1762 hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST); 1763 printf(" Connected to %s", remotehost); 1764 if (strcmp(remotehost, hbuf) != 0) 1765 printf(" (%s)", hbuf); 1766 printf("\r\n"); 1767 if (logged_in) { 1768 if (guest) 1769 printf(" Logged in anonymously\r\n"); 1770 else 1771 printf(" Logged in as %s\r\n", pw->pw_name); 1772 } else if (askpasswd) 1773 printf(" Waiting for password\r\n"); 1774 else 1775 printf(" Waiting for user name\r\n"); 1776 printf(" TYPE: %s", typenames[type]); 1777 if (type == TYPE_A || type == TYPE_E) 1778 printf(", FORM: %s", formnames[form]); 1779 if (type == TYPE_L) 1780#if NBBY == 8 1781 printf(" %d", NBBY); 1782#else 1783 printf(" %d", bytesize); /* need definition! */ 1784#endif 1785 printf("; STRUcture: %s; transfer MODE: %s\r\n", 1786 strunames[stru], modenames[mode]); 1787 ispassive = 0; 1788 if (data != -1) 1789 printf(" Data connection open\r\n"); 1790 else if (pdata != -1) { 1791 printf(" in Passive mode\r\n"); 1792 su = (union sockunion *)&pasv_addr; 1793 ispassive++; 1794 goto printaddr; 1795 } else if (usedefault == 0) { 1796 su = (union sockunion *)&data_dest; 1797printaddr: 1798 /* PASV/PORT */ 1799 if (su->su_family == AF_INET) { 1800 if (ispassive) 1801 printf("211- PASV "); 1802 else 1803 printf("211- PORT "); 1804 a = (u_char *) &su->su_sin.sin_addr; 1805 p = (u_char *) &su->su_sin.sin_port; 1806 printf("(%u,%u,%u,%u,%u,%u)\r\n", 1807 a[0], a[1], a[2], a[3], 1808 p[0], p[1]); 1809 } 1810 1811 /* LPSV/LPRT */ 1812 { 1813 int alen, af, i; 1814 1815 alen = 0; 1816 switch (su->su_family) { 1817 case AF_INET: 1818 a = (u_char *) &su->su_sin.sin_addr; 1819 p = (u_char *) &su->su_sin.sin_port; 1820 alen = sizeof(su->su_sin.sin_addr); 1821 af = 4; 1822 break; 1823 case AF_INET6: 1824 a = (u_char *) &su->su_sin6.sin6_addr; 1825 p = (u_char *) &su->su_sin6.sin6_port; 1826 alen = sizeof(su->su_sin6.sin6_addr); 1827 af = 6; 1828 break; 1829 default: 1830 af = 0; 1831 break; 1832 } 1833 if (af) { 1834 if (ispassive) 1835 printf("211- LPSV "); 1836 else 1837 printf("211- LPRT "); 1838 printf("(%u,%u", af, alen); 1839 for (i = 0; i < alen; i++) 1840 printf(",%u", a[i]); 1841 printf(",%u,%u,%u)\r\n", 2, p[0], p[1]); 1842 } 1843 } 1844 1845 /* EPRT/EPSV */ 1846 { 1847 u_char af; 1848 1849 switch (su->su_family) { 1850 case AF_INET: 1851 af = 1; 1852 break; 1853 case AF_INET6: 1854 af = 2; 1855 break; 1856 default: 1857 af = 0; 1858 break; 1859 } 1860 if (af) { 1861 char hbuf[MAXHOSTNAMELEN], pbuf[10]; 1862 if (getnameinfo((struct sockaddr *)su, su->su_len, 1863 hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), 1864 NI_NUMERICHOST) == 0) { 1865 if (ispassive) 1866 printf("211- EPSV "); 1867 else 1868 printf("211- EPRT "); 1869 printf("(|%u|%s|%s|)\r\n", 1870 af, hbuf, pbuf); 1871 } 1872 } 1873 } 1874 } else 1875 printf(" No data connection\r\n"); 1876 reply(211, "End of status"); 1877} 1878 1879void 1880fatal(s) 1881 char *s; 1882{ 1883 1884 reply(451, "Error in server: %s", s); 1885 reply(221, "Closing connection due to server error."); 1886 dologout(0); 1887 /* NOTREACHED */ 1888} 1889 1890void 1891reply(int n, const char *fmt, ...) 1892{ 1893 char *buf, *p, *next; 1894 va_list ap; 1895 1896 va_start(ap, fmt); 1897 if (vasprintf(&buf, fmt, ap) == -1 || buf == NULL) { 1898 printf("412 Local resource failure: malloc\r\n"); 1899 fflush(stdout); 1900 dologout(1); 1901 } 1902 next = buf; 1903 while ((p = strsep(&next, "\n\r"))) { 1904 printf("%d%s %s\r\n", n, (next != '\0') ? "-" : "", p); 1905 if (debug) 1906 syslog(LOG_DEBUG, "<--- %d%s %s", n, 1907 (next != '\0') ? "-" : "", p); 1908 } 1909 (void)fflush(stdout); 1910 free(buf); 1911 va_end(ap); 1912} 1913 1914void 1915lreply(int n, const char *fmt, ...) 1916{ 1917 va_list ap; 1918 1919 va_start(ap, fmt); 1920 (void)printf("%d- ", n); 1921 (void)vprintf(fmt, ap); 1922 va_end(ap); 1923 (void)printf("\r\n"); 1924 (void)fflush(stdout); 1925 if (debug) { 1926 va_start(ap, fmt); 1927 syslog(LOG_DEBUG, "<--- %d- ", n); 1928 vsyslog(LOG_DEBUG, fmt, ap); 1929 va_end(ap); 1930 } 1931} 1932 1933static void 1934ack(s) 1935 char *s; 1936{ 1937 1938 reply(250, "%s command successful.", s); 1939} 1940 1941void 1942nack(s) 1943 char *s; 1944{ 1945 1946 reply(502, "%s command not implemented.", s); 1947} 1948 1949/* ARGSUSED */ 1950void 1951yyerror(s) 1952 char *s; 1953{ 1954 char *cp; 1955 1956 if ((cp = strchr(cbuf,'\n'))) 1957 *cp = '\0'; 1958 reply(500, "'%s': command not understood.", cbuf); 1959} 1960 1961void 1962delete(name) 1963 char *name; 1964{ 1965 struct stat st; 1966 1967 LOGCMD("delete", name); 1968 if (stat(name, &st) < 0) { 1969 perror_reply(550, name); 1970 return; 1971 } 1972 if ((st.st_mode&S_IFMT) == S_IFDIR) { 1973 if (rmdir(name) < 0) { 1974 perror_reply(550, name); 1975 return; 1976 } 1977 goto done; 1978 } 1979 if (unlink(name) < 0) { 1980 perror_reply(550, name); 1981 return; 1982 } 1983done: 1984 ack("DELE"); 1985} 1986 1987void 1988cwd(path) 1989 char *path; 1990{ 1991 FILE *message; 1992 1993 if (chdir(path) < 0) 1994 perror_reply(550, path); 1995 else { 1996 if ((message = fopen(_PATH_CWDMESG, "r")) != NULL) { 1997 char *cp, line[LINE_MAX]; 1998 1999 while (fgets(line, sizeof(line), message) != NULL) { 2000 if ((cp = strchr(line, '\n')) != NULL) 2001 *cp = '\0'; 2002 lreply(250, "%s", line); 2003 } 2004 (void) fflush(stdout); 2005 (void) fclose(message); 2006 } 2007 ack("CWD"); 2008 } 2009} 2010 2011void 2012replydirname(name, message) 2013 const char *name, *message; 2014{ 2015 char *p, *ep; 2016 char npath[MAXPATHLEN * 2]; 2017 2018 p = npath; 2019 ep = &npath[sizeof(npath) - 1]; 2020 while (*name) { 2021 if (*name == '"') { 2022 if (ep - p < 2) 2023 break; 2024 *p++ = *name++; 2025 *p++ = '"'; 2026 } else { 2027 if (ep - p < 1) 2028 break; 2029 *p++ = *name++; 2030 } 2031 } 2032 *p = '\0'; 2033 reply(257, "\"%s\" %s", npath, message); 2034} 2035 2036void 2037makedir(name) 2038 char *name; 2039{ 2040 2041 LOGCMD("mkdir", name); 2042 if (mkdir(name, 0777) < 0) 2043 perror_reply(550, name); 2044 else 2045 replydirname(name, "directory created."); 2046} 2047 2048void 2049removedir(name) 2050 char *name; 2051{ 2052 2053 LOGCMD("rmdir", name); 2054 if (rmdir(name) < 0) 2055 perror_reply(550, name); 2056 else 2057 ack("RMD"); 2058} 2059 2060void 2061pwd() 2062{ 2063 char path[MAXPATHLEN]; 2064 2065 if (getcwd(path, sizeof(path)) == NULL) 2066 reply(550, "Can't get current directory: %s.", strerror(errno)); 2067 else 2068 replydirname(path, "is current directory."); 2069} 2070 2071char * 2072renamefrom(name) 2073 char *name; 2074{ 2075 struct stat st; 2076 2077 if (stat(name, &st) < 0) { 2078 perror_reply(550, name); 2079 return ((char *)0); 2080 } 2081 reply(350, "File exists, ready for destination name"); 2082 return (name); 2083} 2084 2085void 2086renamecmd(from, to) 2087 char *from, *to; 2088{ 2089 2090 LOGCMD2("rename", from, to); 2091 if (rename(from, to) < 0) 2092 perror_reply(550, "rename"); 2093 else 2094 ack("RNTO"); 2095} 2096 2097static void 2098dolog(sa) 2099 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(status) 2122 int status; 2123{ 2124 2125 transflag = 0; 2126 2127 if (logged_in) { 2128 sigprocmask(SIG_BLOCK, &allsigs, NULL); 2129 (void) seteuid((uid_t)0); 2130 ftpdlogwtmp(ttyline, "", ""); 2131 if (doutmp) 2132 logout(utmp.ut_line); 2133 } 2134 /* beware of flushing buffers after a SIGPIPE */ 2135 _exit(status); 2136} 2137 2138static void 2139sigurg(signo) 2140 int signo; 2141{ 2142 2143 recvurg = 1; 2144} 2145 2146static void 2147myoob() 2148{ 2149 char *cp; 2150 2151 /* only process if transfer occurring */ 2152 if (!transflag) 2153 return; 2154 cp = tmpline; 2155 if (getline(cp, 7, stdin) == NULL) { 2156 reply(221, "You could at least say goodbye."); 2157 dologout(0); 2158 } 2159 upper(cp); 2160 if (strcmp(cp, "ABOR\r\n") == 0) { 2161 tmpline[0] = '\0'; 2162 reply(426, "Transfer aborted. Data connection closed."); 2163 reply(226, "Abort successful"); 2164 } 2165 if (strcmp(cp, "STAT\r\n") == 0) { 2166 tmpline[0] = '\0'; 2167 if (file_size != (off_t) -1) 2168 reply(213, "Status: %qd of %qd bytes transferred", 2169 byte_count, file_size); 2170 else 2171 reply(213, "Status: %qd bytes transferred", byte_count); 2172 } 2173} 2174 2175/* 2176 * Note: a response of 425 is not mentioned as a possible response to 2177 * the PASV command in RFC959. However, it has been blessed as 2178 * a legitimate response by Jon Postel in a telephone conversation 2179 * with Rick Adams on 25 Jan 89. 2180 */ 2181void 2182passive() 2183{ 2184 int len, on; 2185 u_char *p, *a; 2186 2187 if (pw == NULL) { 2188 reply(530, "Please login with USER and PASS"); 2189 return; 2190 } 2191 if (pdata >= 0) 2192 close(pdata); 2193 /* 2194 * XXX 2195 * At this point, it would be nice to have an algorithm that 2196 * inserted a growing delay in an attack scenario. Such a thing 2197 * would look like continual passive sockets being opened, but 2198 * nothing serious being done with them. They're not used to 2199 * move data; the entire attempt is just to use tcp FIN_WAIT 2200 * resources. 2201 */ 2202 pdata = socket(AF_INET, SOCK_STREAM, 0); 2203 if (pdata < 0) { 2204 perror_reply(425, "Can't open passive connection"); 2205 return; 2206 } 2207 2208#ifdef IP_PORTRANGE 2209 on = high_data_ports ? IP_PORTRANGE_HIGH : IP_PORTRANGE_DEFAULT; 2210 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2211 (char *)&on, sizeof(on)) < 0) 2212 goto pasv_error; 2213#endif 2214 2215 pasv_addr = ctrl_addr; 2216 pasv_addr.su_sin.sin_port = 0; 2217 if (bind(pdata, (struct sockaddr *)&pasv_addr, 2218 pasv_addr.su_len) < 0) 2219 goto pasv_error; 2220 2221 len = sizeof(pasv_addr); 2222 if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0) 2223 goto pasv_error; 2224 if (listen(pdata, 1) < 0) 2225 goto pasv_error; 2226 a = (u_char *) &pasv_addr.su_sin.sin_addr; 2227 p = (u_char *) &pasv_addr.su_sin.sin_port; 2228 2229 reply(227, "Entering Passive Mode (%u,%u,%u,%u,%u,%u)", a[0], 2230 a[1], a[2], a[3], p[0], p[1]); 2231 return; 2232 2233pasv_error: 2234 (void) seteuid((uid_t)pw->pw_uid); 2235 (void) close(pdata); 2236 pdata = -1; 2237 perror_reply(425, "Can't open passive connection"); 2238 return; 2239} 2240 2241/* 2242 * convert protocol identifier to/from AF 2243 */ 2244int 2245lpsvproto2af(int proto) 2246{ 2247 2248 switch (proto) { 2249 case 4: return AF_INET; 2250#ifdef INET6 2251 case 6: return AF_INET6; 2252#endif 2253 default: return -1; 2254 } 2255} 2256 2257int 2258af2lpsvproto(int af) 2259{ 2260 2261 switch (af) { 2262 case AF_INET: return 4; 2263#ifdef INET6 2264 case AF_INET6: return 6; 2265#endif 2266 default: return -1; 2267 } 2268} 2269 2270int 2271epsvproto2af(int proto) 2272{ 2273 2274 switch (proto) { 2275 case 1: return AF_INET; 2276#ifdef INET6 2277 case 2: return AF_INET6; 2278#endif 2279 default: return -1; 2280 } 2281} 2282 2283int 2284af2epsvproto(int af) 2285{ 2286 2287 switch (af) { 2288 case AF_INET: return 1; 2289#ifdef INET6 2290 case AF_INET6: return 2; 2291#endif 2292 default: return -1; 2293 } 2294} 2295 2296/* 2297 * 228 Entering Long Passive Mode (af, hal, h1, h2, h3,..., pal, p1, p2...) 2298 * 229 Entering Extended Passive Mode (|||port|) 2299 */ 2300void 2301long_passive(char *cmd, int pf) 2302{ 2303 int len, on; 2304 u_char *p, *a; 2305 2306 if (!logged_in) { 2307 syslog(LOG_NOTICE, "long passive but not logged in"); 2308 reply(503, "Login with USER first."); 2309 return; 2310 } 2311 2312 if (pf != PF_UNSPEC && ctrl_addr.su_family != pf) { 2313 /* 2314 * XXX 2315 * only EPRT/EPSV ready clients will understand this 2316 */ 2317 if (strcmp(cmd, "EPSV") != 0) 2318 reply(501, "Network protocol mismatch"); /*XXX*/ 2319 else 2320 epsv_protounsupp("Network protocol mismatch"); 2321 2322 return; 2323 } 2324 2325 if (pdata >= 0) 2326 close(pdata); 2327 /* 2328 * XXX 2329 * At this point, it would be nice to have an algorithm that 2330 * inserted a growing delay in an attack scenario. Such a thing 2331 * would look like continual passive sockets being opened, but 2332 * nothing serious being done with them. They not used to move 2333 * data; the entire attempt is just to use tcp FIN_WAIT 2334 * resources. 2335 */ 2336 pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 2337 if (pdata < 0) { 2338 perror_reply(425, "Can't open passive connection"); 2339 return; 2340 } 2341 2342 switch (ctrl_addr.su_family) { 2343 case AF_INET: 2344#ifdef IP_PORTRANGE 2345 on = high_data_ports ? IP_PORTRANGE_HIGH : IP_PORTRANGE_DEFAULT; 2346 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2347 (char *)&on, sizeof(on)) < 0) 2348 goto pasv_error; 2349#endif 2350 break; 2351 case AF_INET6: 2352#ifdef IPV6_PORTRANGE 2353 on = high_data_ports ? IPV6_PORTRANGE_HIGH 2354 : IPV6_PORTRANGE_DEFAULT; 2355 if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE, 2356 (char *)&on, sizeof(on)) < 0) 2357 goto pasv_error; 2358#endif 2359 break; 2360 } 2361 2362 pasv_addr = ctrl_addr; 2363 pasv_addr.su_port = 0; 2364 (void) seteuid((uid_t) 0); 2365 if (bind(pdata, (struct sockaddr *) &pasv_addr, pasv_addr.su_len) < 0) { 2366 (void) seteuid((uid_t) pw->pw_uid); 2367 goto pasv_error; 2368 } 2369 (void) seteuid((uid_t) pw->pw_uid); 2370 len = pasv_addr.su_len; 2371 if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0) 2372 goto pasv_error; 2373 if (listen(pdata, 1) < 0) 2374 goto pasv_error; 2375 p = (u_char *) &pasv_addr.su_port; 2376 2377 if (strcmp(cmd, "LPSV") == 0) { 2378 switch (pasv_addr.su_family) { 2379 case AF_INET: 2380 a = (u_char *) &pasv_addr.su_sin.sin_addr; 2381 reply(228, 2382 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2383 4, 4, a[0], a[1], a[2], a[3], 2, p[0], p[1]); 2384 return; 2385 case AF_INET6: 2386 a = (char *) &pasv_addr.su_sin6.sin6_addr; 2387 reply(228, 2388 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u," 2389 "%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2390 6, 16, a[0], a[1], a[2], a[3], a[4], 2391 a[5], a[6], a[7], a[8], a[9], a[10], 2392 a[11], a[12], a[13], a[14], a[15], 2393 2, p[0], p[1]); 2394 return; 2395 } 2396 } else if (strcmp(cmd, "EPSV") == 0) { 2397 switch (pasv_addr.su_family) { 2398 case AF_INET: 2399 case AF_INET6: 2400 reply(229, "Entering Extended Passive Mode (|||%u|)", 2401 ntohs(pasv_addr.su_port)); 2402 return; 2403 } 2404 } else { 2405 /* more proper error code? */ 2406 } 2407 2408 pasv_error: 2409 (void) close(pdata); 2410 pdata = -1; 2411 perror_reply(425, "Can't open passive connection"); 2412 return; 2413} 2414 2415/* 2416 * EPRT |proto|addr|port| 2417 */ 2418int 2419extended_port(const char *arg) 2420{ 2421 char *tmp = NULL; 2422 char *result[3]; 2423 char *p, *q; 2424 char delim; 2425 struct addrinfo hints; 2426 struct addrinfo *res = NULL; 2427 int i; 2428 unsigned long proto; 2429 2430 if (epsvall) { 2431 reply(501, "EPRT disallowed after EPSV ALL"); 2432 return -1; 2433 } 2434 2435 usedefault = 0; 2436 if (pdata >= 0) { 2437 (void) close(pdata); 2438 pdata = -1; 2439 } 2440 2441 tmp = strdup(arg); 2442 if (!tmp) { 2443 fatal("not enough core."); 2444 /*NOTREACHED*/ 2445 } 2446 p = tmp; 2447 delim = p[0]; 2448 p++; 2449 memset(result, 0, sizeof(result)); 2450 for (i = 0; i < 3; i++) { 2451 q = strchr(p, delim); 2452 if (!q || *q != delim) 2453 goto parsefail; 2454 *q++ = '\0'; 2455 result[i] = p; 2456 p = q; 2457 } 2458 2459 /* some more sanity check */ 2460 p = NULL; 2461 (void)strtoul(result[2], &p, 10); 2462 if (!*result[2] || *p) 2463 goto protounsupp; 2464 p = NULL; 2465 proto = strtoul(result[0], &p, 10); 2466 if (!*result[0] || *p) 2467 goto protounsupp; 2468 2469 memset(&hints, 0, sizeof(hints)); 2470 hints.ai_family = epsvproto2af((int)proto); 2471 if (hints.ai_family < 0) 2472 goto protounsupp; 2473 hints.ai_socktype = SOCK_STREAM; 2474 hints.ai_flags = AI_NUMERICHOST; /*no DNS*/ 2475 if (getaddrinfo(result[1], result[2], &hints, &res)) 2476 goto parsefail; 2477 if (res->ai_next) 2478 goto parsefail; 2479 if (sizeof(data_dest) < res->ai_addrlen) 2480 goto parsefail; 2481 memcpy(&data_dest, res->ai_addr, res->ai_addrlen); 2482 if (his_addr.su_family == AF_INET6 && 2483 data_dest.su_family == AF_INET6) { 2484 /* XXX more sanity checks! */ 2485 data_dest.su_sin6.sin6_scope_id = 2486 his_addr.su_sin6.sin6_scope_id; 2487 } 2488 if (pdata >= 0) { 2489 (void) close(pdata); 2490 pdata = -1; 2491 } 2492 reply(200, "EPRT command successful."); 2493 2494 if (tmp) 2495 free(tmp); 2496 if (res) 2497 freeaddrinfo(res); 2498 return 0; 2499 2500parsefail: 2501 reply(500, "Invalid argument, rejected."); 2502 usedefault = 1; 2503 if (tmp) 2504 free(tmp); 2505 if (res) 2506 freeaddrinfo(res); 2507 return -1; 2508 2509protounsupp: 2510 epsv_protounsupp("Protocol not supported"); 2511 usedefault = 1; 2512 if (tmp) 2513 free(tmp); 2514 if (res) 2515 freeaddrinfo(res); 2516 return -1; 2517} 2518 2519/* 2520 * 522 Protocol not supported (proto,...) 2521 * as we assume address family for control and data connections are the same, 2522 * we do not return the list of address families we support - instead, we 2523 * return the address family of the control connection. 2524 */ 2525void 2526epsv_protounsupp(const char *message) 2527{ 2528 int proto; 2529 2530 proto = af2epsvproto(ctrl_addr.su_family); 2531 if (proto < 0) 2532 reply(501, "%s", message); /*XXX*/ 2533 else 2534 reply(522, "%s, use (%d)", message, proto); 2535} 2536 2537/* 2538 * Generate unique name for file with basename "local". 2539 * The file named "local" is already known to exist. 2540 * Generates failure reply on error. 2541 */ 2542static int 2543guniquefd(local, nam) 2544 char *local; 2545 char **nam; 2546{ 2547 static char new[MAXPATHLEN]; 2548 struct stat st; 2549 int count, len, fd; 2550 char *cp; 2551 2552 cp = strrchr(local, '/'); 2553 if (cp) 2554 *cp = '\0'; 2555 if (stat(cp ? local : ".", &st) < 0) { 2556 perror_reply(553, cp ? local : "."); 2557 return (-1); 2558 } 2559 if (cp) 2560 *cp = '/'; 2561 len = strlcpy(new, local, sizeof(new)); 2562 if (len+2+1 >= sizeof(new)-1) 2563 return (-1); 2564 cp = new + len; 2565 *cp++ = '.'; 2566 for (count = 1; count < 100; count++) { 2567 (void)snprintf(cp, sizeof(new) - (cp - new), "%d", count); 2568 fd = open(new, O_RDWR|O_CREAT|O_EXCL, 0666); 2569 if (fd == -1) 2570 continue; 2571 if (nam) 2572 *nam = new; 2573 return (fd); 2574 } 2575 reply(452, "Unique file name cannot be created."); 2576 return (-1); 2577} 2578 2579/* 2580 * Format and send reply containing system error number. 2581 */ 2582void 2583perror_reply(code, string) 2584 int code; 2585 char *string; 2586{ 2587 2588 reply(code, "%s: %s.", string, strerror(errno)); 2589} 2590 2591static char *onefile[] = { 2592 "", 2593 0 2594}; 2595 2596void 2597send_file_list(whichf) 2598 char *whichf; 2599{ 2600 struct stat st; 2601 DIR *dirp = NULL; 2602 struct dirent *dir; 2603 FILE *dout = NULL; 2604 char **dirlist; 2605 char *dirname; 2606 int simple = 0; 2607 volatile int freeglob = 0; 2608 glob_t gl; 2609 2610 if (strpbrk(whichf, "~{[*?") != NULL) { 2611 memset(&gl, 0, sizeof(gl)); 2612 freeglob = 1; 2613 if (glob(whichf, 2614 GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE|GLOB_LIMIT, 2615 0, &gl)) { 2616 reply(550, "not found"); 2617 goto out; 2618 } else if (gl.gl_pathc == 0) { 2619 errno = ENOENT; 2620 perror_reply(550, whichf); 2621 goto out; 2622 } 2623 dirlist = gl.gl_pathv; 2624 } else { 2625 onefile[0] = whichf; 2626 dirlist = onefile; 2627 simple = 1; 2628 } 2629 2630 while ((dirname = *dirlist++)) { 2631 if (stat(dirname, &st) < 0) { 2632 /* 2633 * If user typed "ls -l", etc, and the client 2634 * used NLST, do what the user meant. 2635 */ 2636 if (dirname[0] == '-' && *dirlist == NULL && 2637 transflag == 0) { 2638 retrieve("/bin/ls %s", dirname); 2639 goto out; 2640 } 2641 perror_reply(550, whichf); 2642 if (dout != NULL) { 2643 (void) fclose(dout); 2644 transflag = 0; 2645 data = -1; 2646 pdata = -1; 2647 } 2648 goto out; 2649 } 2650 2651 if (S_ISREG(st.st_mode)) { 2652 if (dout == NULL) { 2653 dout = dataconn("file list", (off_t)-1, "w"); 2654 if (dout == NULL) 2655 goto out; 2656 transflag++; 2657 } 2658 fprintf(dout, "%s%s\n", dirname, 2659 type == TYPE_A ? "\r" : ""); 2660 byte_count += strlen(dirname) + 1; 2661 continue; 2662 } else if (!S_ISDIR(st.st_mode)) 2663 continue; 2664 2665 if ((dirp = opendir(dirname)) == NULL) 2666 continue; 2667 2668 while ((dir = readdir(dirp)) != NULL) { 2669 char nbuf[MAXPATHLEN]; 2670 2671 if (recvurg) { 2672 myoob(); 2673 recvurg = 0; 2674 transflag = 0; 2675 goto out; 2676 } 2677 2678 if (dir->d_name[0] == '.' && dir->d_namlen == 1) 2679 continue; 2680 if (dir->d_name[0] == '.' && dir->d_name[1] == '.' && 2681 dir->d_namlen == 2) 2682 continue; 2683 2684 snprintf(nbuf, sizeof(nbuf), "%s/%s", dirname, 2685 dir->d_name); 2686 2687 /* 2688 * We have to do a stat to insure it's 2689 * not a directory or special file. 2690 */ 2691 if (simple || (stat(nbuf, &st) == 0 && 2692 S_ISREG(st.st_mode))) { 2693 if (dout == NULL) { 2694 dout = dataconn("file list", (off_t)-1, 2695 "w"); 2696 if (dout == NULL) 2697 goto out; 2698 transflag++; 2699 } 2700 if (nbuf[0] == '.' && nbuf[1] == '/') 2701 fprintf(dout, "%s%s\n", &nbuf[2], 2702 type == TYPE_A ? "\r" : ""); 2703 else 2704 fprintf(dout, "%s%s\n", nbuf, 2705 type == TYPE_A ? "\r" : ""); 2706 byte_count += strlen(nbuf) + 1; 2707 } 2708 } 2709 (void) closedir(dirp); 2710 } 2711 2712 if (dout == NULL) 2713 reply(550, "No files found."); 2714 else if (ferror(dout) != 0) 2715 perror_reply(550, "Data connection"); 2716 else 2717 reply(226, "Transfer complete."); 2718 2719 transflag = 0; 2720 if (dout != NULL) 2721 (void) fclose(dout); 2722 else { 2723 if (pdata >= 0) 2724 close(pdata); 2725 } 2726 data = -1; 2727 pdata = -1; 2728out: 2729 if (freeglob) { 2730 freeglob = 0; 2731 globfree(&gl); 2732 } 2733} 2734 2735static void 2736reapchild(signo) 2737 int signo; 2738{ 2739 int save_errno = errno; 2740 int rval; 2741 2742 do { 2743 rval = waitpid(-1, NULL, WNOHANG); 2744 } while (rval > 0 || (rval == -1 && errno == EINTR)); 2745 errno = save_errno; 2746} 2747 2748void 2749logxfer(name, size, start) 2750 char *name; 2751 off_t size; 2752 time_t start; 2753{ 2754 char buf[400 + MAXHOSTNAMELEN*4 + MAXPATHLEN*4]; 2755 char dir[MAXPATHLEN], path[MAXPATHLEN], rpath[MAXPATHLEN]; 2756 char vremotehost[MAXHOSTNAMELEN*4], vpath[MAXPATHLEN*4]; 2757 char *vpw; 2758 time_t now; 2759 int len; 2760 2761 if ((statfd >= 0) && (getcwd(dir, sizeof(dir)) != NULL)) { 2762 time(&now); 2763 2764 vpw = malloc(strlen(guest ? guestpw : pw->pw_name) * 4 + 1); 2765 if (vpw == NULL) 2766 return; 2767 2768 snprintf(path, sizeof(path), "%s/%s", dir, name); 2769 if (realpath(path, rpath) == NULL) 2770 strlcpy(rpath, path, sizeof(rpath)); 2771 strvis(vpath, rpath, VIS_SAFE|VIS_NOSLASH); 2772 2773 strvis(vremotehost, remotehost, VIS_SAFE|VIS_NOSLASH); 2774 strvis(vpw, guest? guestpw : pw->pw_name, VIS_SAFE|VIS_NOSLASH); 2775 2776 len = snprintf(buf, sizeof(buf), 2777 "%.24s %d %s %qd %s %c %s %c %c %s ftp %d %s %s\n", 2778 ctime(&now), now - start + (now == start), 2779 vremotehost, (long long) size, vpath, 2780 ((type == TYPE_A) ? 'a' : 'b'), "*" /* none yet */, 2781 'o', ((guest) ? 'a' : 'r'), 2782 vpw, 0 /* none yet */, 2783 ((guest) ? "*" : pw->pw_name), dhostname); 2784 if (len >= sizeof(buf)) { 2785 len = sizeof(buf); 2786 buf[sizeof(buf) - 1] = '\n'; 2787 } 2788 write(statfd, buf, len); 2789 free(vpw); 2790 } 2791} 2792 2793#if defined(TCPWRAPPERS) 2794static int 2795check_host(sa) 2796 struct sockaddr *sa; 2797{ 2798 struct sockaddr_in *sin; 2799 struct hostent *hp; 2800 char *addr; 2801 2802 if (sa->sa_family != AF_INET) 2803 return 1; /*XXX*/ 2804 2805 sin = (struct sockaddr_in *)sa; 2806 hp = gethostbyaddr((char *)&sin->sin_addr, 2807 sizeof(struct in_addr), AF_INET); 2808 addr = inet_ntoa(sin->sin_addr); 2809 if (hp) { 2810 if (!hosts_ctl("ftpd", hp->h_name, addr, STRING_UNKNOWN)) { 2811 syslog(LOG_NOTICE, "tcpwrappers rejected: %s [%s]", 2812 hp->h_name, addr); 2813 return (0); 2814 } 2815 } else { 2816 if (!hosts_ctl("ftpd", STRING_UNKNOWN, addr, STRING_UNKNOWN)) { 2817 syslog(LOG_NOTICE, "tcpwrappers rejected: [%s]", addr); 2818 return (0); 2819 } 2820 } 2821 return (1); 2822} 2823#endif /* TCPWRAPPERS */ 2824 2825/* 2826 * Allocate space and return a copy of the specified dir. 2827 * If 'dir' begins with a tilde (~), expand it. 2828 */ 2829char * 2830copy_dir(dir, pw) 2831 char *dir; 2832 struct passwd *pw; 2833{ 2834 char *cp; 2835 char *newdir; 2836 char *user = NULL; 2837 size_t dirsiz; 2838 2839 /* Nothing to expand */ 2840 if (dir[0] != '~') 2841 return (strdup(dir)); 2842 2843 /* "dir" is of form ~user/some/dir, lookup user. */ 2844 if (dir[1] != '/' && dir[1] != '\0') { 2845 if ((cp = strchr(dir + 1, '/')) == NULL) 2846 cp = dir + strlen(dir); 2847 if ((user = malloc(cp - dir)) == NULL) 2848 return (NULL); 2849 strlcpy(user, dir + 1, cp - dir); 2850 2851 /* Only do lookup if it is a different user. */ 2852 if (strcmp(user, pw->pw_name) != 0) { 2853 if ((pw = getpwnam(user)) == NULL) { 2854 /* No such user, interpret literally */ 2855 free(user); 2856 return(strdup(dir)); 2857 } 2858 } 2859 } 2860 2861 /* 2862 * If there is no directory separator (/) then it is just pw_dir. 2863 * Otherwise, replace ~foo with pw_dir. 2864 */ 2865 if ((cp = strchr(dir + 1, '/')) == NULL) { 2866 newdir = strdup(pw->pw_dir); 2867 } else { 2868 dirsiz = strlen(cp) + strlen(pw->pw_dir) + 1; 2869 if ((newdir = malloc(dirsiz)) == NULL) { 2870 free(user); 2871 return (NULL); 2872 } 2873 strlcpy(newdir, pw->pw_dir, dirsiz); 2874 strlcat(newdir, cp, dirsiz); 2875 } 2876 2877 if (user) 2878 free(user); 2879 return(newdir); 2880} 2881