ftpd.c revision 1.129
1/* $OpenBSD: ftpd.c,v 1.129 2002/06/17 19:33:37 danh 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 1.129 2002/06/17 19:33:37 danh 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 strlcat(path, "/", sizeof 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 sa.sa_handler = toolong; 498 (void) sigaction(SIGALRM, &sa, NULL); 499 500 addrlen = sizeof(ctrl_addr); 501 if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) { 502 syslog(LOG_ERR, "getsockname: %m"); 503 exit(1); 504 } 505 if (his_addr.su_family == AF_INET6 506 && IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr)) { 507#if 1 508 /* 509 * IPv4 control connection arrived to AF_INET6 socket. 510 * I hate to do this, but this is the easiest solution. 511 */ 512 union sockunion tmp_addr; 513 const int off = sizeof(struct in6_addr) - sizeof(struct in_addr); 514 515 tmp_addr = his_addr; 516 memset(&his_addr, 0, sizeof(his_addr)); 517 his_addr.su_sin.sin_family = AF_INET; 518 his_addr.su_sin.sin_len = sizeof(his_addr.su_sin); 519 memcpy(&his_addr.su_sin.sin_addr, 520 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 521 sizeof(his_addr.su_sin.sin_addr)); 522 his_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 523 524 tmp_addr = ctrl_addr; 525 memset(&ctrl_addr, 0, sizeof(ctrl_addr)); 526 ctrl_addr.su_sin.sin_family = AF_INET; 527 ctrl_addr.su_sin.sin_len = sizeof(ctrl_addr.su_sin); 528 memcpy(&ctrl_addr.su_sin.sin_addr, 529 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 530 sizeof(ctrl_addr.su_sin.sin_addr)); 531 ctrl_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 532#else 533 while (fgets(line, sizeof(line), fd) != NULL) { 534 if ((cp = strchr(line, '\n')) != NULL) 535 *cp = '\0'; 536 lreply(530, "%s", line); 537 } 538 (void) fflush(stdout); 539 (void) fclose(fd); 540 reply(530, 541 "Connection from IPv4 mapped address is not supported."); 542 exit(0); 543#endif 544 } 545#ifdef IP_TOS 546 if (his_addr.su_family == AF_INET) { 547 tos = IPTOS_LOWDELAY; 548 if (setsockopt(0, IPPROTO_IP, IP_TOS, (char *)&tos, 549 sizeof(int)) < 0) 550 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 551 } 552#endif 553 data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1); 554 555 /* Try to handle urgent data inline */ 556#ifdef SO_OOBINLINE 557 if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, (char *)&on, sizeof(on)) < 0) 558 syslog(LOG_ERR, "setsockopt: %m"); 559#endif 560 561#ifdef F_SETOWN 562 if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1) 563 syslog(LOG_ERR, "fcntl F_SETOWN: %m"); 564#endif 565 dolog((struct sockaddr *)&his_addr); 566 /* 567 * Set up default state 568 */ 569 data = -1; 570 type = TYPE_A; 571 form = FORM_N; 572 stru = STRU_F; 573 mode = MODE_S; 574 tmpline[0] = '\0'; 575 576 /* If logins are disabled, print out the message. */ 577 if ((fp = fopen(_PATH_NOLOGIN, "r")) != NULL) { 578 while (fgets(line, sizeof(line), fp) != NULL) { 579 if ((cp = strchr(line, '\n')) != NULL) 580 *cp = '\0'; 581 lreply(530, "%s", line); 582 } 583 (void) fflush(stdout); 584 (void) fclose(fp); 585 reply(530, "System not available."); 586 exit(0); 587 } 588 if ((fp = fopen(_PATH_FTPWELCOME, "r")) != NULL) { 589 while (fgets(line, sizeof(line), fp) != NULL) { 590 if ((cp = strchr(line, '\n')) != NULL) 591 *cp = '\0'; 592 lreply(220, "%s", line); 593 } 594 (void) fflush(stdout); 595 (void) fclose(fp); 596 /* reply(220,) must follow */ 597 } 598 (void) gethostname(hostname, sizeof(hostname)); 599 600 /* Make sure hostname is fully qualified. */ 601 hp = gethostbyname(hostname); 602 if (hp != NULL) 603 strlcpy(hostname, hp->h_name, sizeof(hostname)); 604 605 if (multihome) { 606 getnameinfo((struct sockaddr *)&ctrl_addr, ctrl_addr.su_len, 607 dhostname, sizeof(dhostname), NULL, 0, 0); 608 } 609 610 reply(220, "%s FTP server (%s) ready.", 611 (multihome ? dhostname : hostname), version); 612 for (;;) 613 (void) yyparse(); 614 /* NOTREACHED */ 615} 616 617/* 618 * Signal handlers. 619 */ 620 621static void 622lostconn(signo) 623 int signo; 624{ 625 struct syslog_data sdata = SYSLOG_DATA_INIT; 626 627 if (debug) 628 syslog_r(LOG_DEBUG, &sdata, "lost connection"); 629 dologout(1); 630} 631 632static void 633sigquit(signo) 634 int signo; 635{ 636 struct syslog_data sdata = SYSLOG_DATA_INIT; 637 638 syslog_r(LOG_ERR, &sdata, "got signal %s", sys_signame[signo]); 639 dologout(1); 640} 641 642/* 643 * Save the result of a getpwnam. Used for USER command, since 644 * the data returned must not be clobbered by any other command 645 * (e.g., globbing). 646 */ 647static struct passwd * 648sgetpwnam(name) 649 char *name; 650{ 651 static struct passwd *save; 652 struct passwd *pw; 653 654 if ((pw = getpwnam(name)) == NULL) 655 return (NULL); 656 if (save) { 657 memset(save->pw_passwd, 0, strlen(save->pw_passwd)); 658 free(save); 659 } 660 save = pw_dup(pw); 661 if (save == NULL) { 662 perror_reply(421, "Local resource failure: malloc"); 663 dologout(1); 664 /* NOTREACHED */ 665 } 666 return (save); 667} 668 669static int login_attempts; /* number of failed login attempts */ 670static int askpasswd; /* had user command, ask for passwd */ 671static char curname[MAXLOGNAME]; /* current USER name */ 672 673/* 674 * USER command. 675 * Sets global passwd pointer pw if named account exists and is acceptable; 676 * sets askpasswd if a PASS command is expected. If logged in previously, 677 * need to reset state. If name is "ftp" or "anonymous", the name is not in 678 * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return. 679 * If account doesn't exist, ask for passwd anyway. Otherwise, check user 680 * requesting login privileges. Disallow anyone who does not have a standard 681 * shell as returned by getusershell(). Disallow anyone mentioned in the file 682 * _PATH_FTPUSERS to allow people such as root and uucp to be avoided. 683 */ 684void 685user(name) 686 char *name; 687{ 688 char *cp, *shell, *style, *host; 689 char *class = NULL; 690 691 if (logged_in) { 692 if (guest) { 693 reply(530, "Can't change user from guest login."); 694 return; 695 } else if (dochroot) { 696 reply(530, "Can't change user from chroot user."); 697 return; 698 } 699 end_login(); 700 } 701 702 /* Close session from previous user if there was one. */ 703 if (as) { 704 auth_close(as); 705 as = NULL; 706 } 707 if (lc) { 708 login_close(lc); 709 lc = NULL; 710 } 711 712 if ((style = strchr(name, ':')) != NULL) 713 *style++ = 0; 714 715 guest = 0; 716 host = multihome ? dhostname : hostname; 717 if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) { 718 if (checkuser(_PATH_FTPUSERS, "ftp") || 719 checkuser(_PATH_FTPUSERS, "anonymous")) 720 reply(530, "User %s access denied.", name); 721 else if ((pw = sgetpwnam("ftp")) != NULL) { 722 guest = 1; 723 askpasswd = 1; 724 lc = login_getclass(pw->pw_class); 725 if ((as = auth_open()) == NULL || 726 auth_setpwd(as, pw) != 0 || 727 auth_setoption(as, "FTPD_HOST", host) < 0) { 728 if (as) { 729 auth_close(as); 730 as = NULL; 731 } 732 login_close(lc); 733 lc = NULL; 734 reply(421, "Local resource failure"); 735 return; 736 } 737 reply(331, 738 "Guest login ok, send your email address as password."); 739 } else 740 reply(530, "User %s unknown.", name); 741 if (!askpasswd && logging) 742 syslog(LOG_NOTICE, 743 "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost); 744 return; 745 } 746 747 shell = _PATH_BSHELL; 748 if ((pw = sgetpwnam(name))) { 749 class = pw->pw_class; 750 if (pw->pw_shell != NULL && *pw->pw_shell != '\0') 751 shell = pw->pw_shell; 752 while ((cp = getusershell()) != NULL) 753 if (strcmp(cp, shell) == 0) 754 break; 755 shell = cp; 756 endusershell(); 757 } 758 759 /* Get login class; if invalid style treat like unknown user. */ 760 lc = login_getclass(class); 761 if (lc && (style = login_getstyle(lc, style, "auth-ftp")) == NULL) { 762 login_close(lc); 763 lc = NULL; 764 pw = NULL; 765 } 766 767 /* Do pre-authentication setup. */ 768 if (lc && ((as = auth_open()) == NULL || 769 (pw != NULL && auth_setpwd(as, pw) != 0) || 770 auth_setitem(as, AUTHV_STYLE, style) < 0 || 771 auth_setitem(as, AUTHV_NAME, name) < 0 || 772 auth_setitem(as, AUTHV_CLASS, class) < 0 || 773 auth_setoption(as, "login", "yes") < 0 || 774 auth_setoption(as, "notickets", "yes") < 0 || 775 auth_setoption(as, "FTPD_HOST", host) < 0)) { 776 if (as) { 777 auth_close(as); 778 as = NULL; 779 } 780 login_close(lc); 781 lc = NULL; 782 reply(421, "Local resource failure"); 783 return; 784 } 785 if (logging) 786 strlcpy(curname, name, sizeof(curname)); 787 788 dochroot = (lc && login_getcapbool(lc, "ftp-chroot", 0)) || 789 checkuser(_PATH_FTPCHROOT, name); 790 if (anon_only && !dochroot) { 791 reply(530, "Sorry, only anonymous ftp allowed."); 792 return; 793 } 794 if (pw) { 795 if ((!shell && !dochroot) || checkuser(_PATH_FTPUSERS, name)) { 796 reply(530, "User %s access denied.", name); 797 if (logging) 798 syslog(LOG_NOTICE, 799 "FTP LOGIN REFUSED FROM %s, %s", 800 remotehost, name); 801 pw = NULL; 802 return; 803 } 804 } 805 806 if (as != NULL && (cp = auth_challenge(as)) != NULL) 807 reply(331, cp); 808 else 809 reply(331, "Password required for %s.", name); 810 811 askpasswd = 1; 812 /* 813 * Delay before reading passwd after first failed 814 * attempt to slow down passwd-guessing programs. 815 */ 816 if (login_attempts) 817 sleep((unsigned) login_attempts); 818} 819 820/* 821 * Check if a user is in the file "fname" 822 */ 823static int 824checkuser(fname, name) 825 char *fname; 826 char *name; 827{ 828 FILE *fp; 829 int found = 0; 830 char *p, line[BUFSIZ]; 831 832 if ((fp = fopen(fname, "r")) != NULL) { 833 while (fgets(line, sizeof(line), fp) != NULL) 834 if ((p = strchr(line, '\n')) != NULL) { 835 *p = '\0'; 836 if (line[0] == '#') 837 continue; 838 if (strcmp(line, name) == 0) { 839 found = 1; 840 break; 841 } 842 } 843 (void) fclose(fp); 844 } 845 return (found); 846} 847 848/* 849 * Terminate login as previous user, if any, resetting state; 850 * used when USER command is given or login fails. 851 */ 852static void 853end_login() 854{ 855 856 sigprocmask (SIG_BLOCK, &allsigs, NULL); 857 (void) seteuid((uid_t)0); 858 if (logged_in) { 859 ftpdlogwtmp(ttyline, "", ""); 860 if (doutmp) 861 logout(utmp.ut_line); 862 } 863 pw = NULL; 864 /* umask is restored in ftpcmd.y */ 865 setusercontext(NULL, getpwuid(0), (uid_t)0, 866 LOGIN_SETPRIORITY|LOGIN_SETRESOURCES); 867 logged_in = 0; 868 guest = 0; 869 dochroot = 0; 870} 871 872void 873pass(passwd) 874 char *passwd; 875{ 876 int authok, flags; 877 FILE *fp; 878 static char homedir[MAXPATHLEN]; 879 char *motd, *dir, rootdir[MAXPATHLEN]; 880 881 if (logged_in || askpasswd == 0) { 882 reply(503, "Login with USER first."); 883 return; 884 } 885 askpasswd = 0; 886 if (!guest) { /* "ftp" is only account allowed no password */ 887 authok = 0; 888 if (pw == NULL || pw->pw_passwd[0] == '\0') { 889 useconds_t us; 890 891 /* Sleep between 1 and 3 seconds to emulate a crypt. */ 892 us = arc4random() % 3000000; 893 usleep(us); 894 if (as != NULL) { 895 auth_close(as); 896 as = NULL; 897 } 898 } else { 899 authok = auth_userresponse(as, passwd, 0); 900 as = NULL; 901 } 902 if (authok == 0) { 903 reply(530, "Login incorrect."); 904 if (logging) 905 syslog(LOG_NOTICE, 906 "FTP LOGIN FAILED FROM %s, %s", 907 remotehost, curname); 908 pw = NULL; 909 if (login_attempts++ >= 5) { 910 syslog(LOG_NOTICE, 911 "repeated login failures from %s", 912 remotehost); 913 exit(0); 914 } 915 return; 916 } 917 } else if (lc != NULL) { 918 /* Save anonymous' password. */ 919 if (guestpw != NULL) 920 free(guestpw); 921 guestpw = strdup(passwd); 922 if (guestpw == NULL) 923 fatal("Out of memory."); 924 925 authok = auth_approval(as, lc, pw->pw_name, "ftp"); 926 auth_close(as); 927 as = NULL; 928 if (authok == 0) { 929 syslog(LOG_INFO|LOG_AUTH, 930 "FTP LOGIN FAILED (HOST) as %s: approval failure.", 931 pw->pw_name); 932 reply(530, "Approval failure."); 933 exit(0); 934 } 935 } else { 936 syslog(LOG_INFO|LOG_AUTH, 937 "FTP LOGIN CLASS %s MISSING for %s: approval failure.", 938 pw->pw_class, pw->pw_name); 939 reply(530, "Permission denied."); 940 exit(0); 941 } 942 login_attempts = 0; /* this time successful */ 943 if (setegid((gid_t)pw->pw_gid) < 0) { 944 reply(550, "Can't set gid."); 945 return; 946 } 947 /* set umask via setusercontext() unless -u flag was given. */ 948 flags = LOGIN_SETGROUP|LOGIN_SETPRIORITY|LOGIN_SETRESOURCES; 949 if (umaskchange) 950 flags |= LOGIN_SETUMASK; 951 else 952 (void) umask(defumask); 953 setusercontext(lc, pw, (uid_t)0, flags); 954 955 /* open wtmp before chroot */ 956 ftpdlogwtmp(ttyline, pw->pw_name, remotehost); 957 958 /* open utmp before chroot */ 959 if (doutmp) { 960 memset((void *)&utmp, 0, sizeof(utmp)); 961 (void)time(&utmp.ut_time); 962 (void)strncpy(utmp.ut_name, pw->pw_name, sizeof(utmp.ut_name)); 963 (void)strncpy(utmp.ut_host, remotehost, sizeof(utmp.ut_host)); 964 (void)strncpy(utmp.ut_line, ttyline, sizeof(utmp.ut_line)); 965 login(&utmp); 966 } 967 968 /* open stats file before chroot */ 969 if (guest && (stats == 1) && (statfd < 0)) 970 if ((statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND)) < 0) 971 stats = 0; 972 973 logged_in = 1; 974 975 if ((dir = login_getcapstr(lc, "ftp-dir", NULL, NULL))) { 976 char *newdir; 977 978 newdir = copy_dir(dir, pw); 979 if (newdir == NULL) { 980 perror_reply(421, "Local resource failure: malloc"); 981 dologout(1); 982 /* NOTREACHED */ 983 } 984 free(dir); 985 free(pw->pw_dir); 986 pw->pw_dir = newdir; 987 } 988 989 /* make sure pw->pw_dir is big enough to hold "/" */ 990 if (strlen(pw->pw_dir) < 1) { 991 char *newdir; 992 993 newdir = malloc(2); 994 if (newdir == NULL) { 995 perror_reply(421, "Local resource failure: malloc"); 996 dologout(1); 997 /* NOTREACHED */ 998 } 999 strlcpy(newdir, pw->pw_dir, 2); 1000 free(pw->pw_dir); 1001 pw->pw_dir = newdir; 1002 } 1003 1004 if (guest || dochroot) { 1005 if (multihome && guest) { 1006 struct stat ts; 1007 1008 /* Compute root directory. */ 1009 snprintf(rootdir, sizeof(rootdir), "%s/%s", 1010 pw->pw_dir, dhostname); 1011 if (stat(rootdir, &ts) < 0) { 1012 snprintf(rootdir, sizeof(rootdir), "%s/%s", 1013 pw->pw_dir, hostname); 1014 } 1015 } else 1016 strlcpy(rootdir, pw->pw_dir, sizeof(rootdir)); 1017 } 1018 if (guest) { 1019 /* 1020 * We MUST do a chdir() after the chroot. Otherwise 1021 * the old current directory will be accessible as "." 1022 * outside the new root! 1023 */ 1024 if (chroot(rootdir) < 0 || chdir("/") < 0) { 1025 reply(550, "Can't set guest privileges."); 1026 goto bad; 1027 } 1028 strcpy(pw->pw_dir, "/"); 1029 if (setenv("HOME", "/", 1) == -1) { 1030 reply(550, "Can't setup environment."); 1031 goto bad; 1032 } 1033 } else if (dochroot) { 1034 if (chroot(rootdir) < 0 || chdir("/") < 0) { 1035 reply(550, "Can't change root."); 1036 goto bad; 1037 } 1038 strcpy(pw->pw_dir, "/"); 1039 if (setenv("HOME", "/", 1) == -1) { 1040 reply(550, "Can't setup environment."); 1041 goto bad; 1042 } 1043 } else if (chdir(pw->pw_dir) < 0) { 1044 if (chdir("/") < 0) { 1045 reply(530, "User %s: can't change directory to %s.", 1046 pw->pw_name, pw->pw_dir); 1047 goto bad; 1048 } else 1049 lreply(230, "No directory! Logging in with home=/"); 1050 } 1051 if (seteuid((uid_t)pw->pw_uid) < 0) { 1052 reply(550, "Can't set uid."); 1053 goto bad; 1054 } 1055 sigprocmask(SIG_UNBLOCK, &allsigs, NULL); 1056 1057 /* 1058 * Set home directory so that use of ~ (tilde) works correctly. 1059 */ 1060 if (getcwd(homedir, MAXPATHLEN) != NULL) { 1061 if (setenv("HOME", homedir, 1) == -1) { 1062 reply(550, "Can't setup environment."); 1063 goto bad; 1064 } 1065 } 1066 1067 /* 1068 * Display a login message, if it exists. 1069 * N.B. reply(230,) must follow the message. 1070 */ 1071 motd = login_getcapstr(lc, "welcome", NULL, NULL); 1072 if ((fp = fopen(motd ? motd : _PATH_FTPLOGINMESG, "r")) != NULL) { 1073 char *cp, line[LINE_MAX]; 1074 1075 while (fgets(line, sizeof(line), fp) != NULL) { 1076 if ((cp = strchr(line, '\n')) != NULL) 1077 *cp = '\0'; 1078 lreply(230, "%s", line); 1079 } 1080 (void) fflush(stdout); 1081 (void) fclose(fp); 1082 } 1083 if (motd != NULL) 1084 free(motd); 1085 if (guest) { 1086 if (ident != NULL) 1087 free(ident); 1088 ident = strdup(passwd); 1089 if (ident == NULL) 1090 fatal("Ran out of memory."); 1091 reply(230, "Guest login ok, access restrictions apply."); 1092#ifdef HASSETPROCTITLE 1093 snprintf(proctitle, sizeof(proctitle), 1094 "%s: anonymous/%.*s", remotehost, 1095 (int)(sizeof(proctitle) - sizeof(remotehost) - 1096 sizeof(": anonymous/")), passwd); 1097 setproctitle("%s", proctitle); 1098#endif /* HASSETPROCTITLE */ 1099 if (logging) 1100 syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s", 1101 remotehost, passwd); 1102 } else { 1103 reply(230, "User %s logged in.", pw->pw_name); 1104#ifdef HASSETPROCTITLE 1105 snprintf(proctitle, sizeof(proctitle), 1106 "%s: %s", remotehost, pw->pw_name); 1107 setproctitle("%s", proctitle); 1108#endif /* HASSETPROCTITLE */ 1109 if (logging) 1110 syslog(LOG_INFO, "FTP LOGIN FROM %s as %s", 1111 remotehost, pw->pw_name); 1112 } 1113 login_close(lc); 1114 lc = NULL; 1115 return; 1116bad: 1117 /* Forget all about it... */ 1118 login_close(lc); 1119 lc = NULL; 1120 end_login(); 1121} 1122 1123void 1124retrieve(cmd, name) 1125 char *cmd, *name; 1126{ 1127 FILE *fin, *dout; 1128 struct stat st; 1129 int (*closefunc)(FILE *); 1130 time_t start; 1131 1132 if (cmd == 0) { 1133 fin = fopen(name, "r"), closefunc = fclose; 1134 st.st_size = 0; 1135 } else { 1136 char line[BUFSIZ]; 1137 1138 (void) snprintf(line, sizeof(line), cmd, name); 1139 name = line; 1140 fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose; 1141 st.st_size = -1; 1142 st.st_blksize = BUFSIZ; 1143 } 1144 if (fin == NULL) { 1145 if (errno != 0) { 1146 perror_reply(550, name); 1147 if (cmd == 0) { 1148 LOGCMD("get", name); 1149 } 1150 } 1151 return; 1152 } 1153 byte_count = -1; 1154 if (cmd == 0 && (fstat(fileno(fin), &st) < 0 || !S_ISREG(st.st_mode))) { 1155 reply(550, "%s: not a plain file.", name); 1156 goto done; 1157 } 1158 if (restart_point) { 1159 if (type == TYPE_A) { 1160 off_t i, n; 1161 int c; 1162 1163 n = restart_point; 1164 i = 0; 1165 while (i++ < n) { 1166 if ((c=getc(fin)) == EOF) { 1167 perror_reply(550, name); 1168 goto done; 1169 } 1170 if (c == '\n') 1171 i++; 1172 } 1173 } else if (lseek(fileno(fin), restart_point, SEEK_SET) < 0) { 1174 perror_reply(550, name); 1175 goto done; 1176 } 1177 } 1178 dout = dataconn(name, st.st_size, "w"); 1179 if (dout == NULL) 1180 goto done; 1181 time(&start); 1182 send_data(fin, dout, st.st_blksize, st.st_size, 1183 (restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode))); 1184 if ((cmd == 0) && stats) 1185 logxfer(name, byte_count, start); 1186 (void) fclose(dout); 1187 data = -1; 1188done: 1189 if (pdata >= 0) 1190 (void) close(pdata); 1191 pdata = -1; 1192 if (cmd == 0) 1193 LOGBYTES("get", name, byte_count); 1194 (*closefunc)(fin); 1195} 1196 1197void 1198store(name, mode, unique) 1199 char *name, *mode; 1200 int unique; 1201{ 1202 FILE *fout, *din; 1203 int (*closefunc)(FILE *); 1204 struct stat st; 1205 int fd; 1206 1207 if (restart_point && *mode != 'a') 1208 mode = "r+"; 1209 1210 if (unique && stat(name, &st) == 0) { 1211 char *nam; 1212 1213 fd = guniquefd(name, &nam); 1214 if (fd == -1) { 1215 LOGCMD(*mode == 'w' ? "put" : "append", name); 1216 return; 1217 } 1218 name = nam; 1219 fout = fdopen(fd, mode); 1220 } else 1221 fout = fopen(name, mode); 1222 1223 closefunc = fclose; 1224 if (fout == NULL) { 1225 perror_reply(553, name); 1226 LOGCMD(*mode == 'w' ? "put" : "append", name); 1227 return; 1228 } 1229 byte_count = -1; 1230 if (restart_point) { 1231 if (type == TYPE_A) { 1232 off_t i, n; 1233 int c; 1234 1235 n = restart_point; 1236 i = 0; 1237 while (i++ < n) { 1238 if ((c=getc(fout)) == EOF) { 1239 perror_reply(550, name); 1240 goto done; 1241 } 1242 if (c == '\n') 1243 i++; 1244 } 1245 /* 1246 * We must do this seek to "current" position 1247 * because we are changing from reading to 1248 * writing. 1249 */ 1250 if (fseek(fout, 0L, SEEK_CUR) < 0) { 1251 perror_reply(550, name); 1252 goto done; 1253 } 1254 } else if (lseek(fileno(fout), restart_point, SEEK_SET) < 0) { 1255 perror_reply(550, name); 1256 goto done; 1257 } 1258 } 1259 din = dataconn(name, (off_t)-1, "r"); 1260 if (din == NULL) 1261 goto done; 1262 if (receive_data(din, fout) == 0) { 1263 if (unique) 1264 reply(226, "Transfer complete (unique file name:%s).", 1265 name); 1266 else 1267 reply(226, "Transfer complete."); 1268 } 1269 (void) fclose(din); 1270 data = -1; 1271 pdata = -1; 1272done: 1273 LOGBYTES(*mode == 'w' ? "put" : "append", name, byte_count); 1274 (*closefunc)(fout); 1275} 1276 1277static FILE * 1278getdatasock(mode) 1279 char *mode; 1280{ 1281 int on = 1, s, t, tries; 1282 1283 if (data >= 0) 1284 return (fdopen(data, mode)); 1285 sigprocmask (SIG_BLOCK, &allsigs, NULL); 1286 (void) seteuid((uid_t)0); 1287 s = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 1288 if (s < 0) 1289 goto bad; 1290 if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, 1291 (char *) &on, sizeof(on)) < 0) 1292 goto bad; 1293 /* anchor socket to avoid multi-homing problems */ 1294 data_source = ctrl_addr; 1295 data_source.su_port = htons(20); /* ftp-data port */ 1296 for (tries = 1; ; tries++) { 1297 if (bind(s, (struct sockaddr *)&data_source, 1298 data_source.su_len) >= 0) 1299 break; 1300 if (errno != EADDRINUSE || tries > 10) 1301 goto bad; 1302 sleep(tries); 1303 } 1304 (void) seteuid((uid_t)pw->pw_uid); 1305 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1306 1307#ifdef IP_TOS 1308 if (ctrl_addr.su_family == AF_INET) { 1309 on = IPTOS_THROUGHPUT; 1310 if (setsockopt(s, IPPROTO_IP, IP_TOS, (char *)&on, 1311 sizeof(int)) < 0) 1312 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 1313 } 1314#endif 1315#ifdef TCP_NOPUSH 1316 /* 1317 * Turn off push flag to keep sender TCP from sending short packets 1318 * at the boundaries of each write(). Should probably do a SO_SNDBUF 1319 * to set the send buffer size as well, but that may not be desirable 1320 * in heavy-load situations. 1321 */ 1322 on = 1; 1323 if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, (char *)&on, sizeof(on)) < 0) 1324 syslog(LOG_WARNING, "setsockopt (TCP_NOPUSH): %m"); 1325#endif 1326#ifdef SO_SNDBUF 1327 on = 65536; 1328 if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, (char *)&on, sizeof(on)) < 0) 1329 syslog(LOG_WARNING, "setsockopt (SO_SNDBUF): %m"); 1330#endif 1331 1332 return (fdopen(s, mode)); 1333bad: 1334 /* Return the real value of errno (close may change it) */ 1335 t = errno; 1336 (void) seteuid((uid_t)pw->pw_uid); 1337 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1338 (void) close(s); 1339 errno = t; 1340 return (NULL); 1341} 1342 1343static FILE * 1344dataconn(name, size, mode) 1345 char *name; 1346 off_t size; 1347 char *mode; 1348{ 1349 char sizebuf[32]; 1350 FILE *file; 1351 int retry = 0; 1352 in_port_t *p; 1353 char *fa, *ha; 1354 int alen; 1355 1356 file_size = size; 1357 byte_count = 0; 1358 if (size != (off_t) -1) { 1359 (void) snprintf(sizebuf, sizeof(sizebuf), " (%qd bytes)", 1360 size); 1361 } else 1362 sizebuf[0] = '\0'; 1363 if (pdata >= 0) { 1364 union sockunion from; 1365 int s, fromlen = sizeof(from); 1366 1367 (void) alarm ((unsigned) timeout); 1368 s = accept(pdata, (struct sockaddr *)&from, &fromlen); 1369 (void) alarm (0); 1370 if (s < 0) { 1371 reply(425, "Can't open data connection."); 1372 (void) close(pdata); 1373 pdata = -1; 1374 return (NULL); 1375 } 1376 switch (from.su_family) { 1377 case AF_INET: 1378 p = (in_port_t *)&from.su_sin.sin_port; 1379 fa = (u_char *)&from.su_sin.sin_addr; 1380 ha = (u_char *)&his_addr.su_sin.sin_addr; 1381 alen = sizeof(struct in_addr); 1382 break; 1383 case AF_INET6: 1384 p = (in_port_t *)&from.su_sin6.sin6_port; 1385 fa = (u_char *)&from.su_sin6.sin6_addr; 1386 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1387 alen = sizeof(struct in6_addr); 1388 break; 1389 default: 1390 perror_reply(425, "Can't build data connection"); 1391 (void) close(pdata); 1392 (void) close(s); 1393 pdata = -1; 1394 return (NULL); 1395 } 1396 if (from.su_family != his_addr.su_family || 1397 ntohs(*p) < IPPORT_RESERVED) { 1398 perror_reply(425, "Can't build data connection"); 1399 (void) close(pdata); 1400 (void) close(s); 1401 pdata = -1; 1402 return (NULL); 1403 } 1404 if (portcheck && memcmp(fa, ha, alen) != 0) { 1405 perror_reply(435, "Can't build data connection"); 1406 (void) close(pdata); 1407 (void) close(s); 1408 pdata = -1; 1409 return (NULL); 1410 } 1411 (void) close(pdata); 1412 pdata = s; 1413 reply(150, "Opening %s mode data connection for '%s'%s.", 1414 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1415 return (fdopen(pdata, mode)); 1416 } 1417 if (data >= 0) { 1418 reply(125, "Using existing data connection for '%s'%s.", 1419 name, sizebuf); 1420 usedefault = 1; 1421 return (fdopen(data, mode)); 1422 } 1423 if (usedefault) 1424 data_dest = his_addr; 1425 usedefault = 1; 1426 file = getdatasock(mode); 1427 if (file == NULL) { 1428 char hbuf[MAXHOSTNAMELEN], pbuf[10]; 1429 1430 getnameinfo((struct sockaddr *)&data_source, data_source.su_len, 1431 hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), 1432 NI_NUMERICHOST | NI_NUMERICSERV); 1433 reply(425, "Can't create data socket (%s,%s): %s.", 1434 hbuf, pbuf, strerror(errno)); 1435 return (NULL); 1436 } 1437 data = fileno(file); 1438 1439 /* 1440 * attempt to connect to reserved port on client machine; 1441 * this looks like an attack 1442 */ 1443 switch (data_dest.su_family) { 1444 case AF_INET: 1445 p = (in_port_t *)&data_dest.su_sin.sin_port; 1446 fa = (u_char *)&data_dest.su_sin.sin_addr; 1447 ha = (u_char *)&his_addr.su_sin.sin_addr; 1448 alen = sizeof(struct in_addr); 1449 break; 1450 case AF_INET6: 1451 p = (in_port_t *)&data_dest.su_sin6.sin6_port; 1452 fa = (u_char *)&data_dest.su_sin6.sin6_addr; 1453 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1454 alen = sizeof(struct in6_addr); 1455 break; 1456 default: 1457 perror_reply(425, "Can't build data connection"); 1458 (void) fclose(file); 1459 pdata = -1; 1460 return (NULL); 1461 } 1462 if (data_dest.su_family != his_addr.su_family || 1463 ntohs(*p) < IPPORT_RESERVED || ntohs(*p) == 2049) { /* XXX */ 1464 perror_reply(425, "Can't build data connection"); 1465 (void) fclose(file); 1466 data = -1; 1467 return NULL; 1468 } 1469 if (portcheck && memcmp(fa, ha, alen) != 0) { 1470 perror_reply(435, "Can't build data connection"); 1471 (void) fclose(file); 1472 data = -1; 1473 return NULL; 1474 } 1475 while (connect(data, (struct sockaddr *)&data_dest, 1476 data_dest.su_len) < 0) { 1477 if (errno == EADDRINUSE && retry < swaitmax) { 1478 sleep((unsigned) swaitint); 1479 retry += swaitint; 1480 continue; 1481 } 1482 perror_reply(425, "Can't build data connection"); 1483 (void) fclose(file); 1484 data = -1; 1485 return (NULL); 1486 } 1487 reply(150, "Opening %s mode data connection for '%s'%s.", 1488 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1489 return (file); 1490} 1491 1492/* 1493 * Tranfer the contents of "instr" to "outstr" peer using the appropriate 1494 * encapsulation of the data subject to Mode, Structure, and Type. 1495 * 1496 * NB: Form isn't handled. 1497 */ 1498static int 1499send_data(instr, outstr, blksize, filesize, isreg) 1500 FILE *instr, *outstr; 1501 off_t blksize; 1502 off_t filesize; 1503 int isreg; 1504{ 1505 int c, cnt, filefd, netfd; 1506 char *buf, *bp; 1507 size_t len; 1508 1509 transflag++; 1510 switch (type) { 1511 1512 case TYPE_A: 1513 while ((c = getc(instr)) != EOF) { 1514 if (recvurg) 1515 goto got_oob; 1516 byte_count++; 1517 if (c == '\n') { 1518 if (ferror(outstr)) 1519 goto data_err; 1520 (void) putc('\r', outstr); 1521 } 1522 (void) putc(c, outstr); 1523 } 1524 fflush(outstr); 1525 transflag = 0; 1526 if (ferror(instr)) 1527 goto file_err; 1528 if (ferror(outstr)) 1529 goto data_err; 1530 reply(226, "Transfer complete."); 1531 return(0); 1532 1533 case TYPE_I: 1534 case TYPE_L: 1535 /* 1536 * isreg is only set if we are not doing restart and we 1537 * are sending a regular file 1538 */ 1539 netfd = fileno(outstr); 1540 filefd = fileno(instr); 1541 1542 if (isreg && filesize < (off_t)16 * 1024 * 1024) { 1543 buf = mmap(0, filesize, PROT_READ, MAP_SHARED, filefd, 1544 (off_t)0); 1545 if (buf == MAP_FAILED) { 1546 syslog(LOG_WARNING, "mmap(%lu): %m", 1547 (unsigned long)filesize); 1548 goto oldway; 1549 } 1550 bp = buf; 1551 len = filesize; 1552 do { 1553 cnt = write(netfd, bp, len); 1554 if (recvurg) { 1555 munmap(buf, (size_t)filesize); 1556 goto got_oob; 1557 } 1558 len -= cnt; 1559 bp += cnt; 1560 if (cnt > 0) byte_count += cnt; 1561 } while(cnt > 0 && len > 0); 1562 1563 transflag = 0; 1564 munmap(buf, (size_t)filesize); 1565 if (cnt < 0) 1566 goto data_err; 1567 reply(226, "Transfer complete."); 1568 return(0); 1569 } 1570 1571oldway: 1572 if ((buf = malloc((u_int)blksize)) == NULL) { 1573 transflag = 0; 1574 perror_reply(451, "Local resource failure: malloc"); 1575 return(-1); 1576 } 1577 1578 while ((cnt = read(filefd, buf, (u_int)blksize)) > 0 && 1579 write(netfd, buf, cnt) == cnt) 1580 byte_count += cnt; 1581 transflag = 0; 1582 (void)free(buf); 1583 if (cnt != 0) { 1584 if (cnt < 0) 1585 goto file_err; 1586 goto data_err; 1587 } 1588 reply(226, "Transfer complete."); 1589 return(0); 1590 default: 1591 transflag = 0; 1592 reply(550, "Unimplemented TYPE %d in send_data", type); 1593 return(-1); 1594 } 1595 1596data_err: 1597 transflag = 0; 1598 perror_reply(426, "Data connection"); 1599 return(-1); 1600 1601file_err: 1602 transflag = 0; 1603 perror_reply(551, "Error on input file"); 1604 return(-1); 1605 1606got_oob: 1607 myoob(); 1608 recvurg = 0; 1609 transflag = 0; 1610 return(-1); 1611} 1612 1613/* 1614 * Transfer data from peer to "outstr" using the appropriate encapulation of 1615 * the data subject to Mode, Structure, and Type. 1616 * 1617 * N.B.: Form isn't handled. 1618 */ 1619static int 1620receive_data(instr, outstr) 1621 FILE *instr, *outstr; 1622{ 1623 int c; 1624 int cnt; 1625 char buf[BUFSIZ]; 1626 volatile int bare_lfs = 0; 1627 1628 transflag++; 1629 switch (type) { 1630 1631 case TYPE_I: 1632 case TYPE_L: 1633 do { 1634 (void) alarm ((unsigned) timeout); 1635 cnt = read(fileno(instr), buf, sizeof(buf)); 1636 (void) alarm (0); 1637 if (recvurg) 1638 goto got_oob; 1639 1640 if (cnt > 0) { 1641 if (write(fileno(outstr), buf, cnt) != cnt) 1642 goto file_err; 1643 byte_count += cnt; 1644 } 1645 } while (cnt > 0); 1646 if (cnt < 0) 1647 goto data_err; 1648 transflag = 0; 1649 return (0); 1650 1651 case TYPE_E: 1652 reply(553, "TYPE E not implemented."); 1653 transflag = 0; 1654 return (-1); 1655 1656 case TYPE_A: 1657 while ((c = getc(instr)) != EOF) { 1658 if (recvurg) 1659 goto got_oob; 1660 byte_count++; 1661 if (c == '\n') 1662 bare_lfs++; 1663 while (c == '\r') { 1664 if (ferror(outstr)) 1665 goto data_err; 1666 if ((c = getc(instr)) != '\n') { 1667 (void) putc ('\r', outstr); 1668 if (c == '\0' || c == EOF) 1669 goto contin2; 1670 } 1671 } 1672 (void) putc(c, outstr); 1673 contin2: ; 1674 } 1675 fflush(outstr); 1676 if (ferror(instr)) 1677 goto data_err; 1678 if (ferror(outstr)) 1679 goto file_err; 1680 transflag = 0; 1681 if (bare_lfs) { 1682 lreply(226, 1683 "WARNING! %d bare linefeeds received in ASCII mode", 1684 bare_lfs); 1685 printf(" File may not have transferred correctly.\r\n"); 1686 } 1687 return (0); 1688 default: 1689 reply(550, "Unimplemented TYPE %d in receive_data", type); 1690 transflag = 0; 1691 return (-1); 1692 } 1693 1694data_err: 1695 transflag = 0; 1696 perror_reply(426, "Data Connection"); 1697 return (-1); 1698 1699file_err: 1700 transflag = 0; 1701 perror_reply(452, "Error writing file"); 1702 return (-1); 1703 1704got_oob: 1705 myoob(); 1706 recvurg = 0; 1707 transflag = 0; 1708 return (-1); 1709} 1710 1711void 1712statfilecmd(filename) 1713 char *filename; 1714{ 1715 FILE *fin; 1716 int c; 1717 int atstart; 1718 char line[LINE_MAX]; 1719 1720 (void)snprintf(line, sizeof(line), "/bin/ls -lgA %s", filename); 1721 fin = ftpd_popen(line, "r"); 1722 lreply(211, "status of %s:", filename); 1723 atstart = 1; 1724 while ((c = getc(fin)) != EOF) { 1725 if (c == '\n') { 1726 if (ferror(stdout)){ 1727 perror_reply(421, "control connection"); 1728 (void) ftpd_pclose(fin); 1729 dologout(1); 1730 /* NOTREACHED */ 1731 } 1732 if (ferror(fin)) { 1733 perror_reply(551, filename); 1734 (void) ftpd_pclose(fin); 1735 return; 1736 } 1737 (void) putc('\r', stdout); 1738 } 1739 if (atstart && isdigit(c)) 1740 (void) putc(' ', stdout); 1741 (void) putc(c, stdout); 1742 atstart = (c == '\n'); 1743 } 1744 (void) ftpd_pclose(fin); 1745 reply(211, "End of Status"); 1746} 1747 1748void 1749statcmd() 1750{ 1751 union sockunion *su; 1752 u_char *a, *p; 1753 char hbuf[MAXHOSTNAMELEN]; 1754 int ispassive; 1755 1756 lreply(211, "%s FTP server status:", hostname, version); 1757 printf(" %s\r\n", version); 1758 getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len, 1759 hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST); 1760 printf(" Connected to %s", remotehost); 1761 if (strcmp(remotehost, hbuf) != 0) 1762 printf(" (%s)", hbuf); 1763 printf("\r\n"); 1764 if (logged_in) { 1765 if (guest) 1766 printf(" Logged in anonymously\r\n"); 1767 else 1768 printf(" Logged in as %s\r\n", pw->pw_name); 1769 } else if (askpasswd) 1770 printf(" Waiting for password\r\n"); 1771 else 1772 printf(" Waiting for user name\r\n"); 1773 printf(" TYPE: %s", typenames[type]); 1774 if (type == TYPE_A || type == TYPE_E) 1775 printf(", FORM: %s", formnames[form]); 1776 if (type == TYPE_L) 1777#if NBBY == 8 1778 printf(" %d", NBBY); 1779#else 1780 printf(" %d", bytesize); /* need definition! */ 1781#endif 1782 printf("; STRUcture: %s; transfer MODE: %s\r\n", 1783 strunames[stru], modenames[mode]); 1784 ispassive = 0; 1785 if (data != -1) 1786 printf(" Data connection open\r\n"); 1787 else if (pdata != -1) { 1788 printf(" in Passive mode\r\n"); 1789 su = (union sockunion *)&pasv_addr; 1790 ispassive++; 1791 goto printaddr; 1792 } else if (usedefault == 0) { 1793 su = (union sockunion *)&data_dest; 1794printaddr: 1795 /* PASV/PORT */ 1796 if (su->su_family == AF_INET) { 1797 if (ispassive) 1798 printf("211- PASV "); 1799 else 1800 printf("211- PORT "); 1801 a = (u_char *) &su->su_sin.sin_addr; 1802 p = (u_char *) &su->su_sin.sin_port; 1803 printf("(%u,%u,%u,%u,%u,%u)\r\n", 1804 a[0], a[1], a[2], a[3], 1805 p[0], p[1]); 1806 } 1807 1808 /* LPSV/LPRT */ 1809 { 1810 int alen, af, i; 1811 1812 alen = 0; 1813 switch (su->su_family) { 1814 case AF_INET: 1815 a = (u_char *) &su->su_sin.sin_addr; 1816 p = (u_char *) &su->su_sin.sin_port; 1817 alen = sizeof(su->su_sin.sin_addr); 1818 af = 4; 1819 break; 1820 case AF_INET6: 1821 a = (u_char *) &su->su_sin6.sin6_addr; 1822 p = (u_char *) &su->su_sin6.sin6_port; 1823 alen = sizeof(su->su_sin6.sin6_addr); 1824 af = 6; 1825 break; 1826 default: 1827 af = 0; 1828 break; 1829 } 1830 if (af) { 1831 if (ispassive) 1832 printf("211- LPSV "); 1833 else 1834 printf("211- LPRT "); 1835 printf("(%u,%u", af, alen); 1836 for (i = 0; i < alen; i++) 1837 printf(",%u", a[i]); 1838 printf(",%u,%u,%u)\r\n", 2, p[0], p[1]); 1839 } 1840 } 1841 1842 /* EPRT/EPSV */ 1843 { 1844 u_char af; 1845 1846 switch (su->su_family) { 1847 case AF_INET: 1848 af = 1; 1849 break; 1850 case AF_INET6: 1851 af = 2; 1852 break; 1853 default: 1854 af = 0; 1855 break; 1856 } 1857 if (af) { 1858 char hbuf[MAXHOSTNAMELEN], pbuf[10]; 1859 union sockunion tmp = *su; 1860 1861 if (tmp.su_family == AF_INET6) 1862 tmp.su_sin6.sin6_scope_id = 0; 1863 if (getnameinfo((struct sockaddr *)&tmp, tmp.su_len, 1864 hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), 1865 NI_NUMERICHOST | NI_NUMERICSERV) == 0) { 1866 if (ispassive) 1867 printf("211- EPSV "); 1868 else 1869 printf("211- EPRT "); 1870 printf("(|%u|%s|%s|)\r\n", 1871 af, hbuf, pbuf); 1872 } 1873 } 1874 } 1875 } else 1876 printf(" No data connection\r\n"); 1877 reply(211, "End of status"); 1878} 1879 1880void 1881fatal(s) 1882 char *s; 1883{ 1884 1885 reply(451, "Error in server: %s", s); 1886 reply(221, "Closing connection due to server error."); 1887 dologout(0); 1888 /* NOTREACHED */ 1889} 1890 1891void 1892reply(int n, const char *fmt, ...) 1893{ 1894 char *buf, *p, *next; 1895 va_list ap; 1896 1897 va_start(ap, fmt); 1898 if (vasprintf(&buf, fmt, ap) == -1 || buf == NULL) { 1899 printf("412 Local resource failure: malloc\r\n"); 1900 fflush(stdout); 1901 dologout(1); 1902 } 1903 next = buf; 1904 while ((p = strsep(&next, "\n\r"))) { 1905 printf("%d%s %s\r\n", n, (next != '\0') ? "-" : "", p); 1906 if (debug) 1907 syslog(LOG_DEBUG, "<--- %d%s %s", n, 1908 (next != '\0') ? "-" : "", p); 1909 } 1910 (void)fflush(stdout); 1911 free(buf); 1912 va_end(ap); 1913} 1914 1915void 1916lreply(int n, const char *fmt, ...) 1917{ 1918 va_list ap; 1919 1920 va_start(ap, fmt); 1921 (void)printf("%d- ", n); 1922 (void)vprintf(fmt, ap); 1923 va_end(ap); 1924 (void)printf("\r\n"); 1925 (void)fflush(stdout); 1926 if (debug) { 1927 va_start(ap, fmt); 1928 syslog(LOG_DEBUG, "<--- %d- ", n); 1929 vsyslog(LOG_DEBUG, fmt, ap); 1930 va_end(ap); 1931 } 1932} 1933 1934static void 1935ack(s) 1936 char *s; 1937{ 1938 1939 reply(250, "%s command successful.", s); 1940} 1941 1942void 1943nack(s) 1944 char *s; 1945{ 1946 1947 reply(502, "%s command not implemented.", s); 1948} 1949 1950/* ARGSUSED */ 1951void 1952yyerror(s) 1953 char *s; 1954{ 1955 char *cp; 1956 1957 if ((cp = strchr(cbuf,'\n'))) 1958 *cp = '\0'; 1959 reply(500, "'%s': command not understood.", cbuf); 1960} 1961 1962void 1963delete(name) 1964 char *name; 1965{ 1966 struct stat st; 1967 1968 LOGCMD("delete", name); 1969 if (stat(name, &st) < 0) { 1970 perror_reply(550, name); 1971 return; 1972 } 1973 if ((st.st_mode&S_IFMT) == S_IFDIR) { 1974 if (rmdir(name) < 0) { 1975 perror_reply(550, name); 1976 return; 1977 } 1978 goto done; 1979 } 1980 if (unlink(name) < 0) { 1981 perror_reply(550, name); 1982 return; 1983 } 1984done: 1985 ack("DELE"); 1986} 1987 1988void 1989cwd(path) 1990 char *path; 1991{ 1992 FILE *message; 1993 1994 if (chdir(path) < 0) 1995 perror_reply(550, path); 1996 else { 1997 if ((message = fopen(_PATH_CWDMESG, "r")) != NULL) { 1998 char *cp, line[LINE_MAX]; 1999 2000 while (fgets(line, sizeof(line), message) != NULL) { 2001 if ((cp = strchr(line, '\n')) != NULL) 2002 *cp = '\0'; 2003 lreply(250, "%s", line); 2004 } 2005 (void) fflush(stdout); 2006 (void) fclose(message); 2007 } 2008 ack("CWD"); 2009 } 2010} 2011 2012void 2013replydirname(name, message) 2014 const char *name, *message; 2015{ 2016 char *p, *ep; 2017 char npath[MAXPATHLEN * 2]; 2018 2019 p = npath; 2020 ep = &npath[sizeof(npath) - 1]; 2021 while (*name) { 2022 if (*name == '"') { 2023 if (ep - p < 2) 2024 break; 2025 *p++ = *name++; 2026 *p++ = '"'; 2027 } else { 2028 if (ep - p < 1) 2029 break; 2030 *p++ = *name++; 2031 } 2032 } 2033 *p = '\0'; 2034 reply(257, "\"%s\" %s", npath, message); 2035} 2036 2037void 2038makedir(name) 2039 char *name; 2040{ 2041 2042 LOGCMD("mkdir", name); 2043 if (mkdir(name, 0777) < 0) 2044 perror_reply(550, name); 2045 else 2046 replydirname(name, "directory created."); 2047} 2048 2049void 2050removedir(name) 2051 char *name; 2052{ 2053 2054 LOGCMD("rmdir", name); 2055 if (rmdir(name) < 0) 2056 perror_reply(550, name); 2057 else 2058 ack("RMD"); 2059} 2060 2061void 2062pwd() 2063{ 2064 char path[MAXPATHLEN]; 2065 2066 if (getcwd(path, sizeof(path)) == NULL) 2067 reply(550, "Can't get current directory: %s.", strerror(errno)); 2068 else 2069 replydirname(path, "is current directory."); 2070} 2071 2072char * 2073renamefrom(name) 2074 char *name; 2075{ 2076 struct stat st; 2077 2078 if (stat(name, &st) < 0) { 2079 perror_reply(550, name); 2080 return ((char *)0); 2081 } 2082 reply(350, "File exists, ready for destination name"); 2083 return (name); 2084} 2085 2086void 2087renamecmd(from, to) 2088 char *from, *to; 2089{ 2090 2091 LOGCMD2("rename", from, to); 2092 if (rename(from, to) < 0) 2093 perror_reply(550, "rename"); 2094 else 2095 ack("RNTO"); 2096} 2097 2098static void 2099dolog(sa) 2100 struct sockaddr *sa; 2101{ 2102 char hbuf[sizeof(remotehost)]; 2103 2104 getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), NULL, 0, 0); 2105 (void) strlcpy(remotehost, hbuf, sizeof(remotehost)); 2106 2107#ifdef HASSETPROCTITLE 2108 snprintf(proctitle, sizeof(proctitle), "%s: connected", remotehost); 2109 setproctitle("%s", proctitle); 2110#endif /* HASSETPROCTITLE */ 2111 2112 if (logging) 2113 syslog(LOG_INFO, "connection from %s", remotehost); 2114} 2115 2116/* 2117 * Record logout in wtmp file and exit with supplied status. 2118 * NOTE: because this is called from signal handlers it cannot 2119 * use stdio (or call other functions that use stdio). 2120 */ 2121void 2122dologout(status) 2123 int status; 2124{ 2125 2126 transflag = 0; 2127 2128 if (logged_in) { 2129 sigprocmask(SIG_BLOCK, &allsigs, NULL); 2130 (void) seteuid((uid_t)0); 2131 ftpdlogwtmp(ttyline, "", ""); 2132 if (doutmp) 2133 logout(utmp.ut_line); 2134 } 2135 /* beware of flushing buffers after a SIGPIPE */ 2136 _exit(status); 2137} 2138 2139static void 2140sigurg(signo) 2141 int signo; 2142{ 2143 2144 recvurg = 1; 2145} 2146 2147static void 2148myoob() 2149{ 2150 char *cp; 2151 2152 /* only process if transfer occurring */ 2153 if (!transflag) 2154 return; 2155 cp = tmpline; 2156 if (getline(cp, 7, stdin) == NULL) { 2157 reply(221, "You could at least say goodbye."); 2158 dologout(0); 2159 } 2160 upper(cp); 2161 if (strcmp(cp, "ABOR\r\n") == 0) { 2162 tmpline[0] = '\0'; 2163 reply(426, "Transfer aborted. Data connection closed."); 2164 reply(226, "Abort successful"); 2165 } 2166 if (strcmp(cp, "STAT\r\n") == 0) { 2167 tmpline[0] = '\0'; 2168 if (file_size != (off_t) -1) 2169 reply(213, "Status: %qd of %qd bytes transferred", 2170 byte_count, file_size); 2171 else 2172 reply(213, "Status: %qd bytes transferred", byte_count); 2173 } 2174} 2175 2176/* 2177 * Note: a response of 425 is not mentioned as a possible response to 2178 * the PASV command in RFC959. However, it has been blessed as 2179 * a legitimate response by Jon Postel in a telephone conversation 2180 * with Rick Adams on 25 Jan 89. 2181 */ 2182void 2183passive() 2184{ 2185 int len, on; 2186 u_char *p, *a; 2187 2188 if (pw == NULL) { 2189 reply(530, "Please login with USER and PASS"); 2190 return; 2191 } 2192 if (pdata >= 0) 2193 close(pdata); 2194 /* 2195 * XXX 2196 * At this point, it would be nice to have an algorithm that 2197 * inserted a growing delay in an attack scenario. Such a thing 2198 * would look like continual passive sockets being opened, but 2199 * nothing serious being done with them. They're not used to 2200 * move data; the entire attempt is just to use tcp FIN_WAIT 2201 * resources. 2202 */ 2203 pdata = socket(AF_INET, SOCK_STREAM, 0); 2204 if (pdata < 0) { 2205 perror_reply(425, "Can't open passive connection"); 2206 return; 2207 } 2208 2209#ifdef IP_PORTRANGE 2210 on = high_data_ports ? IP_PORTRANGE_HIGH : IP_PORTRANGE_DEFAULT; 2211 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2212 (char *)&on, sizeof(on)) < 0) 2213 goto pasv_error; 2214#endif 2215 2216 pasv_addr = ctrl_addr; 2217 pasv_addr.su_sin.sin_port = 0; 2218 if (bind(pdata, (struct sockaddr *)&pasv_addr, 2219 pasv_addr.su_len) < 0) 2220 goto pasv_error; 2221 2222 len = sizeof(pasv_addr); 2223 if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0) 2224 goto pasv_error; 2225 if (listen(pdata, 1) < 0) 2226 goto pasv_error; 2227 a = (u_char *) &pasv_addr.su_sin.sin_addr; 2228 p = (u_char *) &pasv_addr.su_sin.sin_port; 2229 2230 reply(227, "Entering Passive Mode (%u,%u,%u,%u,%u,%u)", a[0], 2231 a[1], a[2], a[3], p[0], p[1]); 2232 return; 2233 2234pasv_error: 2235 (void) seteuid((uid_t)pw->pw_uid); 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 int len, on; 2305 u_char *p, *a; 2306 2307 if (!logged_in) { 2308 syslog(LOG_NOTICE, "long passive but not logged in"); 2309 reply(503, "Login with USER first."); 2310 return; 2311 } 2312 2313 if (pf != PF_UNSPEC && ctrl_addr.su_family != pf) { 2314 /* 2315 * XXX 2316 * only EPRT/EPSV ready clients will understand this 2317 */ 2318 if (strcmp(cmd, "EPSV") != 0) 2319 reply(501, "Network protocol mismatch"); /*XXX*/ 2320 else 2321 epsv_protounsupp("Network protocol mismatch"); 2322 2323 return; 2324 } 2325 2326 if (pdata >= 0) 2327 close(pdata); 2328 /* 2329 * XXX 2330 * At this point, it would be nice to have an algorithm that 2331 * inserted a growing delay in an attack scenario. Such a thing 2332 * would look like continual passive sockets being opened, but 2333 * nothing serious being done with them. They not used to move 2334 * data; the entire attempt is just to use tcp FIN_WAIT 2335 * resources. 2336 */ 2337 pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 2338 if (pdata < 0) { 2339 perror_reply(425, "Can't open passive connection"); 2340 return; 2341 } 2342 2343 switch (ctrl_addr.su_family) { 2344 case AF_INET: 2345#ifdef IP_PORTRANGE 2346 on = high_data_ports ? IP_PORTRANGE_HIGH : IP_PORTRANGE_DEFAULT; 2347 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2348 (char *)&on, sizeof(on)) < 0) 2349 goto pasv_error; 2350#endif 2351 break; 2352 case AF_INET6: 2353#ifdef IPV6_PORTRANGE 2354 on = high_data_ports ? IPV6_PORTRANGE_HIGH 2355 : IPV6_PORTRANGE_DEFAULT; 2356 if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE, 2357 (char *)&on, sizeof(on)) < 0) 2358 goto pasv_error; 2359#endif 2360 break; 2361 } 2362 2363 pasv_addr = ctrl_addr; 2364 pasv_addr.su_port = 0; 2365 (void) seteuid((uid_t) 0); 2366 if (bind(pdata, (struct sockaddr *) &pasv_addr, pasv_addr.su_len) < 0) { 2367 (void) seteuid((uid_t) pw->pw_uid); 2368 goto pasv_error; 2369 } 2370 (void) seteuid((uid_t) pw->pw_uid); 2371 len = pasv_addr.su_len; 2372 if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0) 2373 goto pasv_error; 2374 if (listen(pdata, 1) < 0) 2375 goto pasv_error; 2376 p = (u_char *) &pasv_addr.su_port; 2377 2378 if (strcmp(cmd, "LPSV") == 0) { 2379 switch (pasv_addr.su_family) { 2380 case AF_INET: 2381 a = (u_char *) &pasv_addr.su_sin.sin_addr; 2382 reply(228, 2383 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2384 4, 4, a[0], a[1], a[2], a[3], 2, p[0], p[1]); 2385 return; 2386 case AF_INET6: 2387 a = (char *) &pasv_addr.su_sin6.sin6_addr; 2388 reply(228, 2389 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u," 2390 "%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2391 6, 16, a[0], a[1], a[2], a[3], a[4], 2392 a[5], a[6], a[7], a[8], a[9], a[10], 2393 a[11], a[12], a[13], a[14], a[15], 2394 2, p[0], p[1]); 2395 return; 2396 } 2397 } else if (strcmp(cmd, "EPSV") == 0) { 2398 switch (pasv_addr.su_family) { 2399 case AF_INET: 2400 case AF_INET6: 2401 reply(229, "Entering Extended Passive Mode (|||%u|)", 2402 ntohs(pasv_addr.su_port)); 2403 return; 2404 } 2405 } else { 2406 /* more proper error code? */ 2407 } 2408 2409 pasv_error: 2410 (void) close(pdata); 2411 pdata = -1; 2412 perror_reply(425, "Can't open passive connection"); 2413 return; 2414} 2415 2416/* 2417 * EPRT |proto|addr|port| 2418 */ 2419int 2420extended_port(const char *arg) 2421{ 2422 char *tmp = NULL; 2423 char *result[3]; 2424 char *p, *q; 2425 char delim; 2426 struct addrinfo hints; 2427 struct addrinfo *res = NULL; 2428 int i; 2429 unsigned long proto; 2430 2431 if (epsvall) { 2432 reply(501, "EPRT disallowed after EPSV ALL"); 2433 return -1; 2434 } 2435 2436 usedefault = 0; 2437 if (pdata >= 0) { 2438 (void) close(pdata); 2439 pdata = -1; 2440 } 2441 2442 tmp = strdup(arg); 2443 if (!tmp) { 2444 fatal("not enough core."); 2445 /*NOTREACHED*/ 2446 } 2447 p = tmp; 2448 delim = p[0]; 2449 p++; 2450 memset(result, 0, sizeof(result)); 2451 for (i = 0; i < 3; i++) { 2452 q = strchr(p, delim); 2453 if (!q || *q != delim) 2454 goto parsefail; 2455 *q++ = '\0'; 2456 result[i] = p; 2457 p = q; 2458 } 2459 2460 /* some more sanity check */ 2461 p = NULL; 2462 (void)strtoul(result[2], &p, 10); 2463 if (!*result[2] || *p) 2464 goto protounsupp; 2465 p = NULL; 2466 proto = strtoul(result[0], &p, 10); 2467 if (!*result[0] || *p) 2468 goto protounsupp; 2469 2470 memset(&hints, 0, sizeof(hints)); 2471 hints.ai_family = epsvproto2af((int)proto); 2472 if (hints.ai_family < 0) 2473 goto protounsupp; 2474 hints.ai_socktype = SOCK_STREAM; 2475 hints.ai_flags = AI_NUMERICHOST; /*no DNS*/ 2476 if (getaddrinfo(result[1], result[2], &hints, &res)) 2477 goto parsefail; 2478 if (res->ai_next) 2479 goto parsefail; 2480 if (sizeof(data_dest) < res->ai_addrlen) 2481 goto parsefail; 2482 memcpy(&data_dest, res->ai_addr, res->ai_addrlen); 2483 if (his_addr.su_family == AF_INET6 && 2484 data_dest.su_family == AF_INET6) { 2485 /* XXX more sanity checks! */ 2486 data_dest.su_sin6.sin6_scope_id = 2487 his_addr.su_sin6.sin6_scope_id; 2488 } 2489 if (pdata >= 0) { 2490 (void) close(pdata); 2491 pdata = -1; 2492 } 2493 reply(200, "EPRT command successful."); 2494 2495 if (tmp) 2496 free(tmp); 2497 if (res) 2498 freeaddrinfo(res); 2499 return 0; 2500 2501parsefail: 2502 reply(500, "Invalid argument, rejected."); 2503 usedefault = 1; 2504 if (tmp) 2505 free(tmp); 2506 if (res) 2507 freeaddrinfo(res); 2508 return -1; 2509 2510protounsupp: 2511 epsv_protounsupp("Protocol not supported"); 2512 usedefault = 1; 2513 if (tmp) 2514 free(tmp); 2515 if (res) 2516 freeaddrinfo(res); 2517 return -1; 2518} 2519 2520/* 2521 * 522 Protocol not supported (proto,...) 2522 * as we assume address family for control and data connections are the same, 2523 * we do not return the list of address families we support - instead, we 2524 * return the address family of the control connection. 2525 */ 2526void 2527epsv_protounsupp(const char *message) 2528{ 2529 int proto; 2530 2531 proto = af2epsvproto(ctrl_addr.su_family); 2532 if (proto < 0) 2533 reply(501, "%s", message); /*XXX*/ 2534 else 2535 reply(522, "%s, use (%d)", message, proto); 2536} 2537 2538/* 2539 * Generate unique name for file with basename "local". 2540 * The file named "local" is already known to exist. 2541 * Generates failure reply on error. 2542 */ 2543static int 2544guniquefd(local, nam) 2545 char *local; 2546 char **nam; 2547{ 2548 static char new[MAXPATHLEN]; 2549 struct stat st; 2550 int count, len, fd; 2551 char *cp; 2552 2553 cp = strrchr(local, '/'); 2554 if (cp) 2555 *cp = '\0'; 2556 if (stat(cp ? local : ".", &st) < 0) { 2557 perror_reply(553, cp ? local : "."); 2558 return (-1); 2559 } 2560 if (cp) 2561 *cp = '/'; 2562 len = strlcpy(new, local, sizeof(new)); 2563 if (len+2+1 >= sizeof(new)-1) 2564 return (-1); 2565 cp = new + len; 2566 *cp++ = '.'; 2567 for (count = 1; count < 100; count++) { 2568 (void)snprintf(cp, sizeof(new) - (cp - new), "%d", count); 2569 fd = open(new, O_RDWR|O_CREAT|O_EXCL, 0666); 2570 if (fd == -1) 2571 continue; 2572 if (nam) 2573 *nam = new; 2574 return (fd); 2575 } 2576 reply(452, "Unique file name cannot be created."); 2577 return (-1); 2578} 2579 2580/* 2581 * Format and send reply containing system error number. 2582 */ 2583void 2584perror_reply(code, string) 2585 int code; 2586 char *string; 2587{ 2588 2589 reply(code, "%s: %s.", string, strerror(errno)); 2590} 2591 2592static char *onefile[] = { 2593 "", 2594 0 2595}; 2596 2597void 2598send_file_list(whichf) 2599 char *whichf; 2600{ 2601 struct stat st; 2602 DIR *dirp = NULL; 2603 struct dirent *dir; 2604 FILE *dout = NULL; 2605 char **dirlist; 2606 char *dirname; 2607 int simple = 0; 2608 volatile int freeglob = 0; 2609 glob_t gl; 2610 2611 if (strpbrk(whichf, "~{[*?") != NULL) { 2612 memset(&gl, 0, sizeof(gl)); 2613 freeglob = 1; 2614 if (glob(whichf, 2615 GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE|GLOB_LIMIT, 2616 0, &gl)) { 2617 reply(550, "not found"); 2618 goto out; 2619 } else if (gl.gl_pathc == 0) { 2620 errno = ENOENT; 2621 perror_reply(550, whichf); 2622 goto out; 2623 } 2624 dirlist = gl.gl_pathv; 2625 } else { 2626 onefile[0] = whichf; 2627 dirlist = onefile; 2628 simple = 1; 2629 } 2630 2631 while ((dirname = *dirlist++)) { 2632 if (stat(dirname, &st) < 0) { 2633 /* 2634 * If user typed "ls -l", etc, and the client 2635 * used NLST, do what the user meant. 2636 */ 2637 if (dirname[0] == '-' && *dirlist == NULL && 2638 transflag == 0) { 2639 retrieve("/bin/ls %s", dirname); 2640 goto out; 2641 } 2642 perror_reply(550, whichf); 2643 if (dout != NULL) { 2644 (void) fclose(dout); 2645 transflag = 0; 2646 data = -1; 2647 pdata = -1; 2648 } 2649 goto out; 2650 } 2651 2652 if (S_ISREG(st.st_mode)) { 2653 if (dout == NULL) { 2654 dout = dataconn("file list", (off_t)-1, "w"); 2655 if (dout == NULL) 2656 goto out; 2657 transflag++; 2658 } 2659 fprintf(dout, "%s%s\n", dirname, 2660 type == TYPE_A ? "\r" : ""); 2661 byte_count += strlen(dirname) + 1; 2662 continue; 2663 } else if (!S_ISDIR(st.st_mode)) 2664 continue; 2665 2666 if ((dirp = opendir(dirname)) == NULL) 2667 continue; 2668 2669 while ((dir = readdir(dirp)) != NULL) { 2670 char nbuf[MAXPATHLEN]; 2671 2672 if (recvurg) { 2673 myoob(); 2674 recvurg = 0; 2675 transflag = 0; 2676 goto out; 2677 } 2678 2679 if (dir->d_name[0] == '.' && dir->d_namlen == 1) 2680 continue; 2681 if (dir->d_name[0] == '.' && dir->d_name[1] == '.' && 2682 dir->d_namlen == 2) 2683 continue; 2684 2685 snprintf(nbuf, sizeof(nbuf), "%s/%s", dirname, 2686 dir->d_name); 2687 2688 /* 2689 * We have to do a stat to insure it's 2690 * not a directory or special file. 2691 */ 2692 if (simple || (stat(nbuf, &st) == 0 && 2693 S_ISREG(st.st_mode))) { 2694 if (dout == NULL) { 2695 dout = dataconn("file list", (off_t)-1, 2696 "w"); 2697 if (dout == NULL) 2698 goto out; 2699 transflag++; 2700 } 2701 if (nbuf[0] == '.' && nbuf[1] == '/') 2702 fprintf(dout, "%s%s\n", &nbuf[2], 2703 type == TYPE_A ? "\r" : ""); 2704 else 2705 fprintf(dout, "%s%s\n", nbuf, 2706 type == TYPE_A ? "\r" : ""); 2707 byte_count += strlen(nbuf) + 1; 2708 } 2709 } 2710 (void) closedir(dirp); 2711 } 2712 2713 if (dout == NULL) 2714 reply(550, "No files found."); 2715 else if (ferror(dout) != 0) 2716 perror_reply(550, "Data connection"); 2717 else 2718 reply(226, "Transfer complete."); 2719 2720 transflag = 0; 2721 if (dout != NULL) 2722 (void) fclose(dout); 2723 else { 2724 if (pdata >= 0) 2725 close(pdata); 2726 } 2727 data = -1; 2728 pdata = -1; 2729out: 2730 if (freeglob) { 2731 freeglob = 0; 2732 globfree(&gl); 2733 } 2734} 2735 2736static void 2737reapchild(signo) 2738 int signo; 2739{ 2740 int save_errno = errno; 2741 int rval; 2742 2743 do { 2744 rval = waitpid(-1, NULL, WNOHANG); 2745 } while (rval > 0 || (rval == -1 && errno == EINTR)); 2746 errno = save_errno; 2747} 2748 2749void 2750logxfer(name, size, start) 2751 char *name; 2752 off_t size; 2753 time_t start; 2754{ 2755 char buf[400 + MAXHOSTNAMELEN*4 + MAXPATHLEN*4]; 2756 char dir[MAXPATHLEN], path[MAXPATHLEN], rpath[MAXPATHLEN]; 2757 char vremotehost[MAXHOSTNAMELEN*4], vpath[MAXPATHLEN*4]; 2758 char *vpw; 2759 time_t now; 2760 int len; 2761 2762 if ((statfd >= 0) && (getcwd(dir, sizeof(dir)) != NULL)) { 2763 time(&now); 2764 2765 vpw = malloc(strlen(guest ? guestpw : pw->pw_name) * 4 + 1); 2766 if (vpw == NULL) 2767 return; 2768 2769 snprintf(path, sizeof(path), "%s/%s", dir, name); 2770 if (realpath(path, rpath) == NULL) 2771 strlcpy(rpath, path, sizeof(rpath)); 2772 strvis(vpath, rpath, VIS_SAFE|VIS_NOSLASH); 2773 2774 strvis(vremotehost, remotehost, VIS_SAFE|VIS_NOSLASH); 2775 strvis(vpw, guest? guestpw : pw->pw_name, VIS_SAFE|VIS_NOSLASH); 2776 2777 len = snprintf(buf, sizeof(buf), 2778 "%.24s %d %s %qd %s %c %s %c %c %s ftp %d %s %s\n", 2779 ctime(&now), now - start + (now == start), 2780 vremotehost, (long long) size, vpath, 2781 ((type == TYPE_A) ? 'a' : 'b'), "*" /* none yet */, 2782 'o', ((guest) ? 'a' : 'r'), 2783 vpw, 0 /* none yet */, 2784 ((guest) ? "*" : pw->pw_name), dhostname); 2785 if (len >= sizeof(buf)) { 2786 len = sizeof(buf); 2787 buf[sizeof(buf) - 1] = '\n'; 2788 } 2789 write(statfd, buf, len); 2790 free(vpw); 2791 } 2792} 2793 2794#if defined(TCPWRAPPERS) 2795static int 2796check_host(sa) 2797 struct sockaddr *sa; 2798{ 2799 struct sockaddr_in *sin; 2800 struct hostent *hp; 2801 char *addr; 2802 2803 if (sa->sa_family != AF_INET) 2804 return 1; /*XXX*/ 2805 2806 sin = (struct sockaddr_in *)sa; 2807 hp = gethostbyaddr((char *)&sin->sin_addr, 2808 sizeof(struct in_addr), AF_INET); 2809 addr = inet_ntoa(sin->sin_addr); 2810 if (hp) { 2811 if (!hosts_ctl("ftpd", hp->h_name, addr, STRING_UNKNOWN)) { 2812 syslog(LOG_NOTICE, "tcpwrappers rejected: %s [%s]", 2813 hp->h_name, addr); 2814 return (0); 2815 } 2816 } else { 2817 if (!hosts_ctl("ftpd", STRING_UNKNOWN, addr, STRING_UNKNOWN)) { 2818 syslog(LOG_NOTICE, "tcpwrappers rejected: [%s]", addr); 2819 return (0); 2820 } 2821 } 2822 return (1); 2823} 2824#endif /* TCPWRAPPERS */ 2825 2826/* 2827 * Allocate space and return a copy of the specified dir. 2828 * If 'dir' begins with a tilde (~), expand it. 2829 */ 2830char * 2831copy_dir(dir, pw) 2832 char *dir; 2833 struct passwd *pw; 2834{ 2835 char *cp; 2836 char *newdir; 2837 char *user = NULL; 2838 size_t dirsiz; 2839 2840 /* Nothing to expand */ 2841 if (dir[0] != '~') 2842 return (strdup(dir)); 2843 2844 /* "dir" is of form ~user/some/dir, lookup user. */ 2845 if (dir[1] != '/' && dir[1] != '\0') { 2846 if ((cp = strchr(dir + 1, '/')) == NULL) 2847 cp = dir + strlen(dir); 2848 if ((user = malloc(cp - dir)) == NULL) 2849 return (NULL); 2850 strlcpy(user, dir + 1, cp - dir); 2851 2852 /* Only do lookup if it is a different user. */ 2853 if (strcmp(user, pw->pw_name) != 0) { 2854 if ((pw = getpwnam(user)) == NULL) { 2855 /* No such user, interpret literally */ 2856 free(user); 2857 return(strdup(dir)); 2858 } 2859 } 2860 } 2861 2862 /* 2863 * If there is no directory separator (/) then it is just pw_dir. 2864 * Otherwise, replace ~foo with pw_dir. 2865 */ 2866 if ((cp = strchr(dir + 1, '/')) == NULL) { 2867 newdir = strdup(pw->pw_dir); 2868 } else { 2869 dirsiz = strlen(cp) + strlen(pw->pw_dir) + 1; 2870 if ((newdir = malloc(dirsiz)) == NULL) { 2871 free(user); 2872 return (NULL); 2873 } 2874 strlcpy(newdir, pw->pw_dir, dirsiz); 2875 strlcat(newdir, cp, dirsiz); 2876 } 2877 2878 if (user) 2879 free(user); 2880 return(newdir); 2881} 2882