ftpd.c revision 1.106
1/* $OpenBSD: ftpd.c,v 1.106 2001/11/05 09:51:13 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 1.106 2001/11/05 09:51:13 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 <ctype.h> 101#include <dirent.h> 102#include <err.h> 103#include <errno.h> 104#include <fcntl.h> 105#include <glob.h> 106#include <limits.h> 107#include <login_cap.h> 108#include <netdb.h> 109#include <pwd.h> 110#include <setjmp.h> 111#include <signal.h> 112#include <stdio.h> 113#include <stdlib.h> 114#include <string.h> 115#include <syslog.h> 116#include <time.h> 117#include <vis.h> 118#include <unistd.h> 119#include <util.h> 120#include <utmp.h> 121#include <bsd_auth.h> 122 123#if defined(TCPWRAPPERS) 124#include <tcpd.h> 125#endif /* TCPWRAPPERS */ 126 127#include "pathnames.h" 128#include "extern.h" 129 130#ifdef __STDC__ 131#include <stdarg.h> 132#else 133#include <varargs.h> 134#endif 135 136static char version[] = "Version 6.5/OpenBSD"; 137 138extern off_t restart_point; 139extern char cbuf[]; 140 141union sockunion server_addr; 142union sockunion ctrl_addr; 143union sockunion data_source; 144union sockunion data_dest; 145union sockunion his_addr; 146union sockunion pasv_addr; 147 148sigset_t allsigs; 149 150int daemon_mode = 0; 151int data; 152jmp_buf errcatch, urgcatch; 153int logged_in; 154struct passwd *pw; 155int debug = 0; 156int timeout = 900; /* timeout after 15 minutes of inactivity */ 157int maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */ 158int logging; 159int high_data_ports = 0; 160int anon_only = 0; 161int multihome = 0; 162int guest; 163int stats; 164int statfd = -1; 165int portcheck = 1; 166int dochroot; 167int type; 168int form; 169int stru; /* avoid C keyword */ 170int mode; 171int doutmp = 0; /* update utmp file */ 172int usedefault = 1; /* for data transfers */ 173int pdata = -1; /* for passive mode */ 174int family = AF_INET; 175sig_atomic_t transflag; 176off_t file_size; 177off_t byte_count; 178#if !defined(CMASK) || CMASK == 0 179#undef CMASK 180#define CMASK 022 181#endif 182int defumask = CMASK; /* default umask value */ 183int umaskchange = 1; /* allow user to change umask value. */ 184char tmpline[7]; 185char hostname[MAXHOSTNAMELEN]; 186char remotehost[MAXHOSTNAMELEN]; 187char dhostname[MAXHOSTNAMELEN]; 188char *guestpw; 189static char ttyline[20]; 190char *tty = ttyline; /* for klogin */ 191static struct utmp utmp; /* for utmp */ 192static login_cap_t *lc; 193static auth_session_t *as; 194 195#if defined(TCPWRAPPERS) 196int allow_severity = LOG_INFO; 197int deny_severity = LOG_NOTICE; 198#endif /* TCPWRAPPERS */ 199 200char *ident = NULL; 201 202 203int epsvall = 0; 204 205/* 206 * Timeout intervals for retrying connections 207 * to hosts that don't accept PORT cmds. This 208 * is a kludge, but given the problems with TCP... 209 */ 210#define SWAITMAX 90 /* wait at most 90 seconds */ 211#define SWAITINT 5 /* interval between retries */ 212 213int swaitmax = SWAITMAX; 214int swaitint = SWAITINT; 215 216#ifdef HASSETPROCTITLE 217char proctitle[BUFSIZ]; /* initial part of title */ 218#endif /* HASSETPROCTITLE */ 219 220#define LOGCMD(cmd, file) \ 221 if (logging > 1) \ 222 syslog(LOG_INFO,"%s %s%s", cmd, \ 223 *(file) == '/' ? "" : curdir(), file); 224#define LOGCMD2(cmd, file1, file2) \ 225 if (logging > 1) \ 226 syslog(LOG_INFO,"%s %s%s %s%s", cmd, \ 227 *(file1) == '/' ? "" : curdir(), file1, \ 228 *(file2) == '/' ? "" : curdir(), file2); 229#define LOGBYTES(cmd, file, cnt) \ 230 if (logging > 1) { \ 231 if (cnt == (off_t)-1) \ 232 syslog(LOG_INFO,"%s %s%s", cmd, \ 233 *(file) == '/' ? "" : curdir(), file); \ 234 else \ 235 syslog(LOG_INFO, "%s %s%s = %qd bytes", \ 236 cmd, (*(file) == '/') ? "" : curdir(), file, cnt); \ 237 } 238 239static void ack __P((char *)); 240static void myoob __P((int)); 241static int checkuser __P((char *, char *)); 242static FILE *dataconn __P((char *, off_t, char *)); 243static void dolog __P((struct sockaddr *)); 244static char *copy_dir __P((char *, struct passwd *)); 245static char *curdir __P((void)); 246static void end_login __P((void)); 247static FILE *getdatasock __P((char *)); 248static int guniquefd __P((char *, char **)); 249static void lostconn __P((int)); 250static void sigquit __P((int)); 251static int receive_data __P((FILE *, FILE *)); 252static void replydirname __P((const char *, const char *)); 253static void send_data __P((FILE *, FILE *, off_t, off_t, int)); 254static struct passwd * 255 sgetpwnam __P((char *)); 256static void reapchild __P((int)); 257static int check_host __P((struct sockaddr *)); 258static void usage __P((void)); 259 260void logxfer __P((char *, off_t, time_t)); 261 262static char * 263curdir() 264{ 265 static char path[MAXPATHLEN+1]; /* path + '/' */ 266 267 if (getcwd(path, sizeof(path)-1) == NULL) 268 return (""); 269 if (path[1] != '\0') /* special case for root dir. */ 270 strcat(path, "/"); 271 /* For guest account, skip / since it's chrooted */ 272 return (guest ? path+1 : path); 273} 274 275char *argstr = "AdDhlMSt:T:u:UvP46"; 276 277static void 278usage() 279{ 280 syslog(LOG_ERR, 281 "usage: ftpd [-AdDhlMSUv] [-t timeout] [-T maxtimeout] [-u mask]"); 282 exit(2); 283} 284 285int 286main(argc, argv, envp) 287 int argc; 288 char *argv[]; 289 char **envp; 290{ 291 int addrlen, ch, on = 1, tos; 292 char *cp, line[LINE_MAX]; 293 FILE *fp; 294 struct hostent *hp; 295 296 tzset(); /* in case no timezone database in ~ftp */ 297 sigfillset(&allsigs); /* used to block signals while root */ 298 299 while ((ch = getopt(argc, argv, argstr)) != -1) { 300 switch (ch) { 301 case 'A': 302 anon_only = 1; 303 break; 304 305 case 'd': 306 debug = 1; 307 break; 308 309 case 'D': 310 daemon_mode = 1; 311 break; 312 313 case 'P': 314 portcheck = 0; 315 break; 316 317 case 'h': 318 high_data_ports = 1; 319 break; 320 321 case 'l': 322 logging++; /* > 1 == extra logging */ 323 break; 324 325 case 'M': 326 multihome = 1; 327 break; 328 329 case 'S': 330 stats = 1; 331 break; 332 333 case 't': 334 timeout = atoi(optarg); 335 if (maxtimeout < timeout) 336 maxtimeout = timeout; 337 break; 338 339 case 'T': 340 maxtimeout = atoi(optarg); 341 if (timeout > maxtimeout) 342 timeout = maxtimeout; 343 break; 344 345 case 'u': 346 { 347 long val = 0; 348 char *p; 349 umaskchange = 0; 350 351 val = strtol(optarg, &p, 8); 352 if (*p != '\0' || val < 0 || (val & ~ACCESSPERMS)) { 353 syslog(LOG_ERR, 354 "ftpd: %s is a bad value for -u, aborting..", 355 optarg); 356 exit(2); 357 } else 358 defumask = val; 359 break; 360 } 361 362 case 'U': 363 doutmp = 1; 364 break; 365 366 case 'v': 367 debug = 1; 368 break; 369 370 case '4': 371 family = AF_INET; 372 break; 373 374 case '6': 375 family = AF_INET6; 376 break; 377 378 default: 379 usage(); 380 break; 381 } 382 } 383 384 (void) freopen(_PATH_DEVNULL, "w", stderr); 385 386 /* 387 * LOG_NDELAY sets up the logging connection immediately, 388 * necessary for anonymous ftp's that chroot and can't do it later. 389 */ 390 openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP); 391 392 if (daemon_mode) { 393 int ctl_sock, fd; 394 struct servent *sv; 395 396 /* 397 * Detach from parent. 398 */ 399 if (daemon(1, 1) < 0) { 400 syslog(LOG_ERR, "failed to become a daemon"); 401 exit(1); 402 } 403 (void) signal(SIGCHLD, reapchild); 404 /* 405 * Get port number for ftp/tcp. 406 */ 407 sv = getservbyname("ftp", "tcp"); 408 if (sv == NULL) { 409 syslog(LOG_ERR, "getservbyname for ftp failed"); 410 exit(1); 411 } 412 /* 413 * Open a socket, bind it to the FTP port, and start 414 * listening. 415 */ 416 ctl_sock = socket(family, SOCK_STREAM, 0); 417 if (ctl_sock < 0) { 418 syslog(LOG_ERR, "control socket: %m"); 419 exit(1); 420 } 421 if (setsockopt(ctl_sock, SOL_SOCKET, SO_REUSEADDR, 422 (char *)&on, sizeof(on)) < 0) 423 syslog(LOG_ERR, "control setsockopt: %m"); 424 memset(&server_addr, 0, sizeof(server_addr)); 425 server_addr.su_sin.sin_family = family; 426 switch (family) { 427 case AF_INET: 428 server_addr.su_len = sizeof(struct sockaddr_in); 429 server_addr.su_sin.sin_port = sv->s_port; 430 break; 431 case AF_INET6: 432 server_addr.su_len = sizeof(struct sockaddr_in6); 433 server_addr.su_sin6.sin6_port = sv->s_port; 434 break; 435 } 436 if (bind(ctl_sock, (struct sockaddr *)&server_addr, 437 server_addr.su_len)) { 438 syslog(LOG_ERR, "control bind: %m"); 439 exit(1); 440 } 441 if (listen(ctl_sock, 32) < 0) { 442 syslog(LOG_ERR, "control listen: %m"); 443 exit(1); 444 } 445 /* Stash pid in pidfile */ 446 if ((fp = fopen(_PATH_FTPDPID, "w")) == NULL) 447 syslog(LOG_ERR, "can't open %s: %m", _PATH_FTPDPID); 448 else { 449 fprintf(fp, "%d\n", getpid()); 450 fchmod(fileno(fp), S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH); 451 fclose(fp); 452 } 453 /* 454 * Loop forever accepting connection requests and forking off 455 * children to handle them. 456 */ 457 while (1) { 458 addrlen = sizeof(his_addr); 459 fd = accept(ctl_sock, (struct sockaddr *)&his_addr, 460 &addrlen); 461 if (fork() == 0) { 462 /* child */ 463 (void) dup2(fd, 0); 464 (void) dup2(fd, 1); 465 close(ctl_sock); 466 break; 467 } 468 close(fd); 469 } 470 471#if defined(TCPWRAPPERS) 472 /* ..in the child. */ 473 if (!check_host((struct sockaddr *)&his_addr)) 474 exit(1); 475#endif /* TCPWRAPPERS */ 476 } else { 477 addrlen = sizeof(his_addr); 478 if (getpeername(0, (struct sockaddr *)&his_addr, 479 &addrlen) < 0) { 480 /* syslog(LOG_ERR, "getpeername (%s): %m", argv[0]); */ 481 exit(1); 482 } 483 } 484 485 /* set this here so klogin can use it... */ 486 (void)snprintf(ttyline, sizeof(ttyline), "ftp%d", getpid()); 487 488 (void) signal(SIGHUP, sigquit); 489 (void) signal(SIGINT, sigquit); 490 (void) signal(SIGQUIT, sigquit); 491 (void) signal(SIGTERM, sigquit); 492 (void) signal(SIGPIPE, lostconn); 493 (void) signal(SIGCHLD, SIG_IGN); 494 if (signal(SIGURG, myoob) == SIG_ERR) 495 syslog(LOG_ERR, "signal: %m"); 496 497 addrlen = sizeof(ctrl_addr); 498 if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) { 499 syslog(LOG_ERR, "getsockname (%s): %m", argv[0]); 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 strcpy(hostname, hp->h_name); 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 (void) setjmp(errcatch); 610 for (;;) 611 (void) yyparse(); 612 /* NOTREACHED */ 613} 614 615/* 616 * Signal handlers. 617 */ 618 619static void 620lostconn(signo) 621 int signo; 622{ 623 struct syslog_data sdata = SYSLOG_DATA_INIT; 624 625 sigprocmask(SIG_BLOCK, &allsigs, NULL); 626 if (debug) 627 syslog_r(LOG_DEBUG, &sdata, "lost connection"); 628 dologout(1); /* XXX signal race? */ 629} 630 631static void 632sigquit(signo) 633 int signo; 634{ 635 struct syslog_data sdata = SYSLOG_DATA_INIT; 636 637 sigprocmask(SIG_BLOCK, &allsigs, NULL); 638 syslog_r(LOG_ERR, &sdata, "got signal %s", sys_signame[signo]); 639 dologout(1); /* XXX signal race? */ 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 (pw); 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; 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 login_close(lc); 700 lc = NULL; 701 if (as) { 702 auth_close(as); 703 as = NULL; 704 } 705 end_login(); 706 } 707 708 if ((style = strchr(name, ':')) != NULL) 709 *style++ = 0; 710 711 guest = 0; 712 if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) { 713 if (checkuser(_PATH_FTPUSERS, "ftp") || 714 checkuser(_PATH_FTPUSERS, "anonymous")) 715 reply(530, "User %s access denied.", name); 716 else if ((pw = sgetpwnam("ftp")) != NULL) { 717 guest = 1; 718 askpasswd = 1; 719 lc = login_getclass(pw->pw_class); 720 reply(331, 721 "Guest login ok, send your email address as password."); 722 } else 723 reply(530, "User %s unknown.", name); 724 if (!askpasswd && logging) 725 syslog(LOG_NOTICE, 726 "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost); 727 return; 728 } 729 730 shell = _PATH_BSHELL; 731 if ((pw = sgetpwnam(name))) { 732 class = pw->pw_class; 733 if (pw->pw_shell != NULL && *pw->pw_shell != '\0') 734 shell = pw->pw_shell; 735 while ((cp = getusershell()) != NULL) 736 if (strcmp(cp, shell) == 0) 737 break; 738 shell = cp; 739 endusershell(); 740 } 741 742 /* Get login class; if invalid style treat like unknown user. */ 743 lc = login_getclass(class); 744 if (lc && (style = login_getstyle(lc, style, "auth-ftp")) == NULL) { 745 login_close(lc); 746 lc = NULL; 747 pw = NULL; 748 } 749 750 /* Do pre-authentication setup. */ 751 if (lc && ((as = auth_open()) == NULL || 752 auth_setitem(as, AUTHV_STYLE, style) < 0 || 753 auth_setitem(as, AUTHV_NAME, name) < 0 || 754 auth_setitem(as, AUTHV_CLASS, class) < 0 || 755 auth_setoption(as, "login", "yes") < 0 || 756 auth_setoption(as, "notickets", "yes") < 0)) { 757 if (as) { 758 auth_close(as); 759 as = NULL; 760 } 761 login_close(lc); 762 lc = NULL; 763 reply(421, "Local resource failure"); 764 return; 765 } 766 if (logging) 767 strlcpy(curname, name, sizeof(curname)); 768 769 dochroot = (lc && login_getcapbool(lc, "ftp-chroot", 0)) || 770 checkuser(_PATH_FTPCHROOT, name); 771 if (anon_only && !dochroot) { 772 reply(530, "Sorry, only anonymous ftp allowed."); 773 return; 774 } 775 if (pw) { 776 if ((!shell && !dochroot) || checkuser(_PATH_FTPUSERS, name)) { 777 reply(530, "User %s access denied.", name); 778 if (logging) 779 syslog(LOG_NOTICE, 780 "FTP LOGIN REFUSED FROM %s, %s", 781 remotehost, name); 782 pw = NULL; 783 return; 784 } 785 } 786 787 if (as != NULL && (cp = auth_challenge(as)) != NULL) 788 reply(331, cp); 789 else 790 reply(331, "Password required for %s.", name); 791 792 askpasswd = 1; 793 /* 794 * Delay before reading passwd after first failed 795 * attempt to slow down passwd-guessing programs. 796 */ 797 if (login_attempts) 798 sleep((unsigned) login_attempts); 799} 800 801/* 802 * Check if a user is in the file "fname" 803 */ 804static int 805checkuser(fname, name) 806 char *fname; 807 char *name; 808{ 809 FILE *fp; 810 int found = 0; 811 char *p, line[BUFSIZ]; 812 813 if ((fp = fopen(fname, "r")) != NULL) { 814 while (fgets(line, sizeof(line), fp) != NULL) 815 if ((p = strchr(line, '\n')) != NULL) { 816 *p = '\0'; 817 if (line[0] == '#') 818 continue; 819 if (strcmp(line, name) == 0) { 820 found = 1; 821 break; 822 } 823 } 824 (void) fclose(fp); 825 } 826 return (found); 827} 828 829/* 830 * Terminate login as previous user, if any, resetting state; 831 * used when USER command is given or login fails. 832 */ 833static void 834end_login() 835{ 836 837 sigprocmask (SIG_BLOCK, &allsigs, NULL); 838 (void) seteuid((uid_t)0); 839 if (logged_in) { 840 ftpdlogwtmp(ttyline, "", ""); 841 if (doutmp) 842 logout(utmp.ut_line); 843 } 844 pw = NULL; 845 /* umask is restored in ftpcmd.y */ 846 setusercontext(NULL, getpwuid(0), (uid_t)0, 847 LOGIN_SETPRIORITY|LOGIN_SETRESOURCES); 848 logged_in = 0; 849 guest = 0; 850 dochroot = 0; 851} 852 853void 854pass(passwd) 855 char *passwd; 856{ 857 int authok, flags; 858 FILE *fp; 859 static char homedir[MAXPATHLEN]; 860 char *motd, *dir, rootdir[MAXPATHLEN]; 861 862 if (logged_in || askpasswd == 0) { 863 reply(503, "Login with USER first."); 864 return; 865 } 866 askpasswd = 0; 867 if (!guest) { /* "ftp" is only account allowed no password */ 868 authok = 0; 869 if (pw == NULL) { 870 useconds_t us; 871 872 /* Sleep between 1 and 3 seconds to emulate a crypt. */ 873 us = arc4random() % 3000000; 874 usleep(us); 875 } else { 876 authok = auth_userresponse(as, passwd, 0); 877 as = NULL; 878 } 879 if (authok == 0) { 880 reply(530, "Login incorrect."); 881 if (logging) 882 syslog(LOG_NOTICE, 883 "FTP LOGIN FAILED FROM %s, %s", 884 remotehost, curname); 885 pw = NULL; 886 if (login_attempts++ >= 5) { 887 syslog(LOG_NOTICE, 888 "repeated login failures from %s", 889 remotehost); 890 exit(0); 891 } 892 return; 893 } 894 } else if (lc != NULL) { 895 /* Save anonymous' password. */ 896 guestpw = strdup(passwd); 897 if (guestpw == (char *)NULL) 898 fatal("Out of memory"); 899 900 if ((as = auth_open()) == NULL) 901 fatal("Out of memory"); 902 auth_setoption(as, "FTPD_HOST", 903 multihome ? dhostname : hostname); 904 authok = auth_approval(as, lc, pw->pw_name, "ftp"); 905 auth_close(as); 906 as = NULL; 907 if (authok == 0) { 908 syslog(LOG_INFO|LOG_AUTH, 909 "FTP LOGIN FAILED (HOST) as %s: approval failure.", 910 pw->pw_name); 911 reply(530, "Approval failure.\n"); 912 exit(0); 913 } 914 } else { 915 syslog(LOG_INFO|LOG_AUTH, 916 "FTP LOGIN CLASS %s MISSING for %s: approval failure.", 917 pw->pw_class, pw->pw_name); 918 reply(530, "Permission denied.\n"); 919 exit(0); 920 } 921 login_attempts = 0; /* this time successful */ 922 if (setegid((gid_t)pw->pw_gid) < 0) { 923 reply(550, "Can't set gid."); 924 return; 925 } 926 /* set umask via setusercontext() unless -u flag was given. */ 927 flags = LOGIN_SETGROUP|LOGIN_SETPRIORITY|LOGIN_SETRESOURCES; 928 if (umaskchange) 929 flags |= LOGIN_SETUMASK; 930 else 931 (void) umask(defumask); 932 setusercontext(lc, pw, (uid_t)0, flags); 933 934 /* open wtmp before chroot */ 935 ftpdlogwtmp(ttyline, pw->pw_name, remotehost); 936 937 /* open utmp before chroot */ 938 if (doutmp) { 939 memset((void *)&utmp, 0, sizeof(utmp)); 940 (void)time(&utmp.ut_time); 941 (void)strncpy(utmp.ut_name, pw->pw_name, sizeof(utmp.ut_name)); 942 (void)strncpy(utmp.ut_host, remotehost, sizeof(utmp.ut_host)); 943 (void)strncpy(utmp.ut_line, ttyline, sizeof(utmp.ut_line)); 944 login(&utmp); 945 } 946 947 /* open stats file before chroot */ 948 if (guest && (stats == 1) && (statfd < 0)) 949 if ((statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND)) < 0) 950 stats = 0; 951 952 logged_in = 1; 953 954 if ((dir = login_getcapstr(lc, "ftp-dir", NULL, NULL))) { 955 char *newdir; 956 957 newdir = copy_dir(dir, pw); 958 if (newdir == NULL) { 959 perror_reply(421, "Local resource failure: malloc"); 960 dologout(1); 961 /* NOTREACHED */ 962 } 963 free(dir); 964 free(pw->pw_dir); 965 pw->pw_dir = newdir; 966 } 967 968 if (guest || dochroot) { 969 if (multihome && guest) { 970 struct stat ts; 971 972 /* Compute root directory. */ 973 snprintf(rootdir, sizeof(rootdir), "%s/%s", 974 pw->pw_dir, dhostname); 975 if (stat(rootdir, &ts) < 0) { 976 snprintf(rootdir, sizeof(rootdir), "%s/%s", 977 pw->pw_dir, hostname); 978 } 979 } else 980 strcpy(rootdir, pw->pw_dir); 981 } 982 if (guest) { 983 /* 984 * We MUST do a chdir() after the chroot. Otherwise 985 * the old current directory will be accessible as "." 986 * outside the new root! 987 */ 988 if (chroot(rootdir) < 0 || chdir("/") < 0) { 989 reply(550, "Can't set guest privileges."); 990 goto bad; 991 } 992 strcpy(pw->pw_dir, "/"); 993 if (setenv("HOME", "/", 1) == -1) { 994 reply(550, "Can't setup environment."); 995 goto bad; 996 } 997 } else if (dochroot) { 998 if (chroot(rootdir) < 0 || chdir("/") < 0) { 999 reply(550, "Can't change root."); 1000 goto bad; 1001 } 1002 strcpy(pw->pw_dir, "/"); 1003 if (setenv("HOME", "/", 1) == -1) { 1004 reply(550, "Can't setup environment."); 1005 goto bad; 1006 } 1007 } else if (chdir(pw->pw_dir) < 0) { 1008 if (chdir("/") < 0) { 1009 reply(530, "User %s: can't change directory to %s.", 1010 pw->pw_name, pw->pw_dir); 1011 goto bad; 1012 } else 1013 lreply(230, "No directory! Logging in with home=/"); 1014 } 1015 if (seteuid((uid_t)pw->pw_uid) < 0) { 1016 reply(550, "Can't set uid."); 1017 goto bad; 1018 } 1019 sigprocmask(SIG_UNBLOCK, &allsigs, NULL); 1020 1021 /* 1022 * Set home directory so that use of ~ (tilde) works correctly. 1023 */ 1024 if (getcwd(homedir, MAXPATHLEN) != NULL) { 1025 if (setenv("HOME", homedir, 1) == -1) { 1026 reply(550, "Can't setup environment."); 1027 goto bad; 1028 } 1029 } 1030 1031 /* 1032 * Display a login message, if it exists. 1033 * N.B. reply(230,) must follow the message. 1034 */ 1035 motd = login_getcapstr(lc, "welcome", NULL, NULL); 1036 if ((fp = fopen(motd ? motd : _PATH_FTPLOGINMESG, "r")) != NULL) { 1037 char *cp, line[LINE_MAX]; 1038 1039 while (fgets(line, sizeof(line), fp) != NULL) { 1040 if ((cp = strchr(line, '\n')) != NULL) 1041 *cp = '\0'; 1042 lreply(230, "%s", line); 1043 } 1044 (void) fflush(stdout); 1045 (void) fclose(fp); 1046 } 1047 if (motd != NULL) 1048 free(motd); 1049 if (guest) { 1050 if (ident != NULL) 1051 free(ident); 1052 ident = strdup(passwd); 1053 if (ident == NULL) 1054 fatal("Ran out of memory."); 1055 reply(230, "Guest login ok, access restrictions apply."); 1056#ifdef HASSETPROCTITLE 1057 snprintf(proctitle, sizeof(proctitle), 1058 "%s: anonymous/%.*s", remotehost, 1059 (int)(sizeof(proctitle) - sizeof(remotehost) - 1060 sizeof(": anonymous/")), passwd); 1061 setproctitle("%s", proctitle); 1062#endif /* HASSETPROCTITLE */ 1063 if (logging) 1064 syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s", 1065 remotehost, passwd); 1066 } else { 1067 reply(230, "User %s logged in.", pw->pw_name); 1068#ifdef HASSETPROCTITLE 1069 snprintf(proctitle, sizeof(proctitle), 1070 "%s: %s", remotehost, pw->pw_name); 1071 setproctitle("%s", proctitle); 1072#endif /* HASSETPROCTITLE */ 1073 if (logging) 1074 syslog(LOG_INFO, "FTP LOGIN FROM %s as %s", 1075 remotehost, pw->pw_name); 1076 } 1077 login_close(lc); 1078 lc = NULL; 1079 return; 1080bad: 1081 /* Forget all about it... */ 1082 login_close(lc); 1083 lc = NULL; 1084 end_login(); 1085} 1086 1087void 1088retrieve(cmd, name) 1089 char *cmd, *name; 1090{ 1091 FILE *fin, *dout; 1092 struct stat st; 1093 int (*closefunc) __P((FILE *)); 1094 time_t start; 1095 1096 if (cmd == 0) { 1097 fin = fopen(name, "r"), closefunc = fclose; 1098 st.st_size = 0; 1099 } else { 1100 char line[BUFSIZ]; 1101 1102 (void) snprintf(line, sizeof(line), cmd, name); 1103 name = line; 1104 fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose; 1105 st.st_size = -1; 1106 st.st_blksize = BUFSIZ; 1107 } 1108 if (fin == NULL) { 1109 if (errno != 0) { 1110 perror_reply(550, name); 1111 if (cmd == 0) { 1112 LOGCMD("get", name); 1113 } 1114 } 1115 return; 1116 } 1117 byte_count = -1; 1118 if (cmd == 0 && (fstat(fileno(fin), &st) < 0 || !S_ISREG(st.st_mode))) { 1119 reply(550, "%s: not a plain file.", name); 1120 goto done; 1121 } 1122 if (restart_point) { 1123 if (type == TYPE_A) { 1124 off_t i, n; 1125 int c; 1126 1127 n = restart_point; 1128 i = 0; 1129 while (i++ < n) { 1130 if ((c=getc(fin)) == EOF) { 1131 perror_reply(550, name); 1132 goto done; 1133 } 1134 if (c == '\n') 1135 i++; 1136 } 1137 } else if (lseek(fileno(fin), restart_point, SEEK_SET) < 0) { 1138 perror_reply(550, name); 1139 goto done; 1140 } 1141 } 1142 dout = dataconn(name, st.st_size, "w"); 1143 if (dout == NULL) 1144 goto done; 1145 time(&start); 1146 send_data(fin, dout, st.st_blksize, st.st_size, 1147 (restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode))); 1148 if ((cmd == 0) && stats) 1149 logxfer(name, byte_count, start); 1150 (void) fclose(dout); 1151 data = -1; 1152done: 1153 if (pdata >= 0) 1154 (void) close(pdata); 1155 pdata = -1; 1156 if (cmd == 0) 1157 LOGBYTES("get", name, byte_count); 1158 (*closefunc)(fin); 1159} 1160 1161void 1162store(name, mode, unique) 1163 char *name, *mode; 1164 int unique; 1165{ 1166 FILE *fout, *din; 1167 int (*closefunc) __P((FILE *)); 1168 struct stat st; 1169 int fd; 1170 1171 if (restart_point && *mode != 'a') 1172 mode = "r+"; 1173 1174 if (unique && stat(name, &st) == 0) { 1175 char *nam; 1176 1177 fd = guniquefd(name, &nam); 1178 if (fd == -1) { 1179 LOGCMD(*mode == 'w' ? "put" : "append", name); 1180 return; 1181 } 1182 name = nam; 1183 fout = fdopen(fd, mode); 1184 } else 1185 fout = fopen(name, mode); 1186 1187 closefunc = fclose; 1188 if (fout == NULL) { 1189 perror_reply(553, name); 1190 LOGCMD(*mode == 'w' ? "put" : "append", name); 1191 return; 1192 } 1193 byte_count = -1; 1194 if (restart_point) { 1195 if (type == TYPE_A) { 1196 off_t i, n; 1197 int c; 1198 1199 n = restart_point; 1200 i = 0; 1201 while (i++ < n) { 1202 if ((c=getc(fout)) == EOF) { 1203 perror_reply(550, name); 1204 goto done; 1205 } 1206 if (c == '\n') 1207 i++; 1208 } 1209 /* 1210 * We must do this seek to "current" position 1211 * because we are changing from reading to 1212 * writing. 1213 */ 1214 if (fseek(fout, 0L, SEEK_CUR) < 0) { 1215 perror_reply(550, name); 1216 goto done; 1217 } 1218 } else if (lseek(fileno(fout), restart_point, SEEK_SET) < 0) { 1219 perror_reply(550, name); 1220 goto done; 1221 } 1222 } 1223 din = dataconn(name, (off_t)-1, "r"); 1224 if (din == NULL) 1225 goto done; 1226 if (receive_data(din, fout) == 0) { 1227 if (unique) 1228 reply(226, "Transfer complete (unique file name:%s).", 1229 name); 1230 else 1231 reply(226, "Transfer complete."); 1232 } 1233 (void) fclose(din); 1234 data = -1; 1235 pdata = -1; 1236done: 1237 LOGBYTES(*mode == 'w' ? "put" : "append", name, byte_count); 1238 (*closefunc)(fout); 1239} 1240 1241static FILE * 1242getdatasock(mode) 1243 char *mode; 1244{ 1245 int on = 1, s, t, tries; 1246 1247 if (data >= 0) 1248 return (fdopen(data, mode)); 1249 sigprocmask (SIG_BLOCK, &allsigs, NULL); 1250 (void) seteuid((uid_t)0); 1251 s = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 1252 if (s < 0) 1253 goto bad; 1254 if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, 1255 (char *) &on, sizeof(on)) < 0) 1256 goto bad; 1257 /* anchor socket to avoid multi-homing problems */ 1258 data_source = ctrl_addr; 1259 data_source.su_port = htons(20); /* ftp-data port */ 1260 for (tries = 1; ; tries++) { 1261 if (bind(s, (struct sockaddr *)&data_source, 1262 data_source.su_len) >= 0) 1263 break; 1264 if (errno != EADDRINUSE || tries > 10) 1265 goto bad; 1266 sleep(tries); 1267 } 1268 (void) seteuid((uid_t)pw->pw_uid); 1269 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1270 1271#ifdef IP_TOS 1272 if (ctrl_addr.su_family == AF_INET) { 1273 on = IPTOS_THROUGHPUT; 1274 if (setsockopt(s, IPPROTO_IP, IP_TOS, (char *)&on, 1275 sizeof(int)) < 0) 1276 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 1277 } 1278#endif 1279#ifdef TCP_NOPUSH 1280 /* 1281 * Turn off push flag to keep sender TCP from sending short packets 1282 * at the boundaries of each write(). Should probably do a SO_SNDBUF 1283 * to set the send buffer size as well, but that may not be desirable 1284 * in heavy-load situations. 1285 */ 1286 on = 1; 1287 if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, (char *)&on, sizeof(on)) < 0) 1288 syslog(LOG_WARNING, "setsockopt (TCP_NOPUSH): %m"); 1289#endif 1290#ifdef SO_SNDBUF 1291 on = 65536; 1292 if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, (char *)&on, sizeof(on)) < 0) 1293 syslog(LOG_WARNING, "setsockopt (SO_SNDBUF): %m"); 1294#endif 1295 1296 return (fdopen(s, mode)); 1297bad: 1298 /* Return the real value of errno (close may change it) */ 1299 t = errno; 1300 (void) seteuid((uid_t)pw->pw_uid); 1301 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1302 (void) close(s); 1303 errno = t; 1304 return (NULL); 1305} 1306 1307static FILE * 1308dataconn(name, size, mode) 1309 char *name; 1310 off_t size; 1311 char *mode; 1312{ 1313 char sizebuf[32]; 1314 FILE *file; 1315 int retry = 0; 1316 in_port_t *p; 1317 char *fa, *ha; 1318 int alen; 1319 1320 file_size = size; 1321 byte_count = 0; 1322 if (size != (off_t) -1) { 1323 (void) snprintf(sizebuf, sizeof(sizebuf), " (%qd bytes)", 1324 size); 1325 } else 1326 sizebuf[0] = '\0'; 1327 if (pdata >= 0) { 1328 union sockunion from; 1329 int s, fromlen = sizeof(from); 1330 1331 signal (SIGALRM, toolong); 1332 (void) alarm ((unsigned) timeout); 1333 s = accept(pdata, (struct sockaddr *)&from, &fromlen); 1334 (void) alarm (0); 1335 if (s < 0) { 1336 reply(425, "Can't open data connection."); 1337 (void) close(pdata); 1338 pdata = -1; 1339 return (NULL); 1340 } 1341 switch (from.su_family) { 1342 case AF_INET: 1343 p = (in_port_t *)&from.su_sin.sin_port; 1344 fa = (u_char *)&from.su_sin.sin_addr; 1345 ha = (u_char *)&his_addr.su_sin.sin_addr; 1346 alen = sizeof(struct in_addr); 1347 break; 1348 case AF_INET6: 1349 p = (in_port_t *)&from.su_sin6.sin6_port; 1350 fa = (u_char *)&from.su_sin6.sin6_addr; 1351 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1352 alen = sizeof(struct in6_addr); 1353 break; 1354 default: 1355 perror_reply(425, "Can't build data connection"); 1356 (void) close(pdata); 1357 (void) close(s); 1358 pdata = -1; 1359 return (NULL); 1360 } 1361 if (from.su_family != his_addr.su_family || 1362 ntohs(*p) < IPPORT_RESERVED) { 1363 perror_reply(425, "Can't build data connection"); 1364 (void) close(pdata); 1365 (void) close(s); 1366 pdata = -1; 1367 return (NULL); 1368 } 1369 if (portcheck && memcmp(fa, ha, alen) != 0) { 1370 perror_reply(435, "Can't build data connection"); 1371 (void) close(pdata); 1372 (void) close(s); 1373 pdata = -1; 1374 return (NULL); 1375 } 1376 (void) close(pdata); 1377 pdata = s; 1378 reply(150, "Opening %s mode data connection for '%s'%s.", 1379 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1380 return (fdopen(pdata, mode)); 1381 } 1382 if (data >= 0) { 1383 reply(125, "Using existing data connection for '%s'%s.", 1384 name, sizebuf); 1385 usedefault = 1; 1386 return (fdopen(data, mode)); 1387 } 1388 if (usedefault) 1389 data_dest = his_addr; 1390 usedefault = 1; 1391 file = getdatasock(mode); 1392 if (file == NULL) { 1393 char hbuf[MAXHOSTNAMELEN], pbuf[10]; 1394 1395 getnameinfo((struct sockaddr *)&data_source, data_source.su_len, 1396 hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), 1397 NI_NUMERICHOST | NI_NUMERICSERV); 1398 reply(425, "Can't create data socket (%s,%s): %s.", 1399 hbuf, pbuf, strerror(errno)); 1400 return (NULL); 1401 } 1402 data = fileno(file); 1403 1404 /* 1405 * attempt to connect to reserved port on client machine; 1406 * this looks like an attack 1407 */ 1408 switch (data_dest.su_family) { 1409 case AF_INET: 1410 p = (in_port_t *)&data_dest.su_sin.sin_port; 1411 fa = (u_char *)&data_dest.su_sin.sin_addr; 1412 ha = (u_char *)&his_addr.su_sin.sin_addr; 1413 alen = sizeof(struct in_addr); 1414 break; 1415 case AF_INET6: 1416 p = (in_port_t *)&data_dest.su_sin6.sin6_port; 1417 fa = (u_char *)&data_dest.su_sin6.sin6_addr; 1418 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1419 alen = sizeof(struct in6_addr); 1420 break; 1421 default: 1422 perror_reply(425, "Can't build data connection"); 1423 (void) fclose(file); 1424 pdata = -1; 1425 return (NULL); 1426 } 1427 if (data_dest.su_family != his_addr.su_family || 1428 ntohs(*p) < IPPORT_RESERVED || ntohs(*p) == 2049) { /* XXX */ 1429 perror_reply(425, "Can't build data connection"); 1430 (void) fclose(file); 1431 data = -1; 1432 return NULL; 1433 } 1434 if (portcheck && memcmp(fa, ha, alen) != 0) { 1435 perror_reply(435, "Can't build data connection"); 1436 (void) fclose(file); 1437 data = -1; 1438 return NULL; 1439 } 1440 while (connect(data, (struct sockaddr *)&data_dest, 1441 data_dest.su_len) < 0) { 1442 if (errno == EADDRINUSE && retry < swaitmax) { 1443 sleep((unsigned) swaitint); 1444 retry += swaitint; 1445 continue; 1446 } 1447 perror_reply(425, "Can't build data connection"); 1448 (void) fclose(file); 1449 data = -1; 1450 return (NULL); 1451 } 1452 reply(150, "Opening %s mode data connection for '%s'%s.", 1453 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1454 return (file); 1455} 1456 1457/* 1458 * Tranfer the contents of "instr" to "outstr" peer using the appropriate 1459 * encapsulation of the data subject to Mode, Structure, and Type. 1460 * 1461 * NB: Form isn't handled. 1462 */ 1463static void 1464send_data(instr, outstr, blksize, filesize, isreg) 1465 FILE *instr, *outstr; 1466 off_t blksize; 1467 off_t filesize; 1468 int isreg; 1469{ 1470 int c, cnt, filefd, netfd; 1471 char *buf, *bp; 1472 size_t len; 1473 1474 transflag++; 1475 if (setjmp(urgcatch)) { 1476 transflag = 0; 1477 return; 1478 } 1479 switch (type) { 1480 1481 case TYPE_A: 1482 while ((c = getc(instr)) != EOF) { 1483 byte_count++; 1484 if (c == '\n') { 1485 if (ferror(outstr)) 1486 goto data_err; 1487 (void) putc('\r', outstr); 1488 } 1489 (void) putc(c, outstr); 1490 } 1491 fflush(outstr); 1492 transflag = 0; 1493 if (ferror(instr)) 1494 goto file_err; 1495 if (ferror(outstr)) 1496 goto data_err; 1497 reply(226, "Transfer complete."); 1498 return; 1499 1500 case TYPE_I: 1501 case TYPE_L: 1502 /* 1503 * isreg is only set if we are not doing restart and we 1504 * are sending a regular file 1505 */ 1506 netfd = fileno(outstr); 1507 filefd = fileno(instr); 1508 1509 if (isreg && filesize < (off_t)16 * 1024 * 1024) { 1510 buf = mmap(0, filesize, PROT_READ, MAP_SHARED, filefd, 1511 (off_t)0); 1512 if (buf == MAP_FAILED) { 1513 syslog(LOG_WARNING, "mmap(%lu): %m", 1514 (unsigned long)filesize); 1515 goto oldway; 1516 } 1517 bp = buf; 1518 len = filesize; 1519 do { 1520 cnt = write(netfd, bp, len); 1521 len -= cnt; 1522 bp += cnt; 1523 if (cnt > 0) byte_count += cnt; 1524 } while(cnt > 0 && len > 0); 1525 1526 transflag = 0; 1527 munmap(buf, (size_t)filesize); 1528 if (cnt < 0) 1529 goto data_err; 1530 reply(226, "Transfer complete."); 1531 return; 1532 } 1533 1534oldway: 1535 if ((buf = malloc((u_int)blksize)) == NULL) { 1536 transflag = 0; 1537 perror_reply(451, "Local resource failure: malloc"); 1538 return; 1539 } 1540 1541 while ((cnt = read(filefd, buf, (u_int)blksize)) > 0 && 1542 write(netfd, buf, cnt) == cnt) 1543 byte_count += cnt; 1544 transflag = 0; 1545 (void)free(buf); 1546 if (cnt != 0) { 1547 if (cnt < 0) 1548 goto file_err; 1549 goto data_err; 1550 } 1551 reply(226, "Transfer complete."); 1552 return; 1553 default: 1554 transflag = 0; 1555 reply(550, "Unimplemented TYPE %d in send_data", type); 1556 return; 1557 } 1558 1559data_err: 1560 transflag = 0; 1561 perror_reply(426, "Data connection"); 1562 return; 1563 1564file_err: 1565 transflag = 0; 1566 perror_reply(551, "Error on input file"); 1567} 1568 1569/* 1570 * Transfer data from peer to "outstr" using the appropriate encapulation of 1571 * the data subject to Mode, Structure, and Type. 1572 * 1573 * N.B.: Form isn't handled. 1574 */ 1575static int 1576receive_data(instr, outstr) 1577 FILE *instr, *outstr; 1578{ 1579 int c; 1580 int cnt; 1581 volatile int bare_lfs = 0; 1582 char buf[BUFSIZ]; 1583 1584 transflag++; 1585 if (setjmp(urgcatch)) { 1586 transflag = 0; 1587 return (-1); 1588 } 1589 switch (type) { 1590 1591 case TYPE_I: 1592 case TYPE_L: 1593 signal (SIGALRM, lostconn); 1594 1595 do { 1596 (void) alarm ((unsigned) timeout); 1597 cnt = read(fileno(instr), buf, sizeof(buf)); 1598 (void) alarm (0); 1599 1600 if (cnt > 0) { 1601 if (write(fileno(outstr), buf, cnt) != cnt) 1602 goto file_err; 1603 byte_count += cnt; 1604 } 1605 } while (cnt > 0); 1606 if (cnt < 0) 1607 goto data_err; 1608 transflag = 0; 1609 return (0); 1610 1611 case TYPE_E: 1612 reply(553, "TYPE E not implemented."); 1613 transflag = 0; 1614 return (-1); 1615 1616 case TYPE_A: 1617 while ((c = getc(instr)) != EOF) { 1618 byte_count++; 1619 if (c == '\n') 1620 bare_lfs++; 1621 while (c == '\r') { 1622 if (ferror(outstr)) 1623 goto data_err; 1624 if ((c = getc(instr)) != '\n') { 1625 (void) putc ('\r', outstr); 1626 if (c == '\0' || c == EOF) 1627 goto contin2; 1628 } 1629 } 1630 (void) putc(c, outstr); 1631 contin2: ; 1632 } 1633 fflush(outstr); 1634 if (ferror(instr)) 1635 goto data_err; 1636 if (ferror(outstr)) 1637 goto file_err; 1638 transflag = 0; 1639 if (bare_lfs) { 1640 lreply(226, 1641 "WARNING! %d bare linefeeds received in ASCII mode", 1642 bare_lfs); 1643 printf(" File may not have transferred correctly.\r\n"); 1644 } 1645 return (0); 1646 default: 1647 reply(550, "Unimplemented TYPE %d in receive_data", type); 1648 transflag = 0; 1649 return (-1); 1650 } 1651 1652data_err: 1653 transflag = 0; 1654 perror_reply(426, "Data Connection"); 1655 return (-1); 1656 1657file_err: 1658 transflag = 0; 1659 perror_reply(452, "Error writing file"); 1660 return (-1); 1661} 1662 1663void 1664statfilecmd(filename) 1665 char *filename; 1666{ 1667 FILE *fin; 1668 int c; 1669 int atstart; 1670 char line[LINE_MAX]; 1671 1672 (void)snprintf(line, sizeof(line), "/bin/ls -lgA %s", filename); 1673 fin = ftpd_popen(line, "r"); 1674 lreply(211, "status of %s:", filename); 1675 atstart = 1; 1676 while ((c = getc(fin)) != EOF) { 1677 if (c == '\n') { 1678 if (ferror(stdout)){ 1679 perror_reply(421, "control connection"); 1680 (void) ftpd_pclose(fin); 1681 dologout(1); 1682 /* NOTREACHED */ 1683 } 1684 if (ferror(fin)) { 1685 perror_reply(551, filename); 1686 (void) ftpd_pclose(fin); 1687 return; 1688 } 1689 (void) putc('\r', stdout); 1690 } 1691 if (atstart && isdigit(c)) 1692 (void) putc(' ', stdout); 1693 (void) putc(c, stdout); 1694 atstart = (c == '\n'); 1695 } 1696 (void) ftpd_pclose(fin); 1697 reply(211, "End of Status"); 1698} 1699 1700void 1701statcmd() 1702{ 1703 union sockunion *su; 1704 u_char *a, *p; 1705 char hbuf[MAXHOSTNAMELEN]; 1706 int ispassive; 1707 1708 lreply(211, "%s FTP server status:", hostname, version); 1709 printf(" %s\r\n", version); 1710 getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len, 1711 hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST); 1712 printf(" Connected to %s", remotehost); 1713 if (strcmp(remotehost, hbuf) != 0) 1714 printf(" (%s)", hbuf); 1715 printf("\r\n"); 1716 if (logged_in) { 1717 if (guest) 1718 printf(" Logged in anonymously\r\n"); 1719 else 1720 printf(" Logged in as %s\r\n", pw->pw_name); 1721 } else if (askpasswd) 1722 printf(" Waiting for password\r\n"); 1723 else 1724 printf(" Waiting for user name\r\n"); 1725 printf(" TYPE: %s", typenames[type]); 1726 if (type == TYPE_A || type == TYPE_E) 1727 printf(", FORM: %s", formnames[form]); 1728 if (type == TYPE_L) 1729#if NBBY == 8 1730 printf(" %d", NBBY); 1731#else 1732 printf(" %d", bytesize); /* need definition! */ 1733#endif 1734 printf("; STRUcture: %s; transfer MODE: %s\r\n", 1735 strunames[stru], modenames[mode]); 1736 ispassive = 0; 1737 if (data != -1) 1738 printf(" Data connection open\r\n"); 1739 else if (pdata != -1) { 1740 printf(" in Passive mode\r\n"); 1741 su = (union sockunion *)&pasv_addr; 1742 ispassive++; 1743 goto printaddr; 1744 } else if (usedefault == 0) { 1745 su = (union sockunion *)&data_dest; 1746printaddr: 1747 /* PASV/PORT */ 1748 if (su->su_family == AF_INET) { 1749 if (ispassive) 1750 printf("211- PASV "); 1751 else 1752 printf("211- PORT "); 1753 a = (u_char *) &su->su_sin.sin_addr; 1754 p = (u_char *) &su->su_sin.sin_port; 1755 printf("(%u,%u,%u,%u,%u,%u)\r\n", 1756 a[0], a[1], a[2], a[3], 1757 p[0], p[1]); 1758 } 1759 1760 /* LPSV/LPRT */ 1761 { 1762 int alen, af, i; 1763 1764 alen = 0; 1765 switch (su->su_family) { 1766 case AF_INET: 1767 a = (u_char *) &su->su_sin.sin_addr; 1768 p = (u_char *) &su->su_sin.sin_port; 1769 alen = sizeof(su->su_sin.sin_addr); 1770 af = 4; 1771 break; 1772 case AF_INET6: 1773 a = (u_char *) &su->su_sin6.sin6_addr; 1774 p = (u_char *) &su->su_sin6.sin6_port; 1775 alen = sizeof(su->su_sin6.sin6_addr); 1776 af = 6; 1777 break; 1778 default: 1779 af = 0; 1780 break; 1781 } 1782 if (af) { 1783 if (ispassive) 1784 printf("211- LPSV "); 1785 else 1786 printf("211- LPRT "); 1787 printf("(%u,%u", af, alen); 1788 for (i = 0; i < alen; i++) 1789 printf(",%u", a[i]); 1790 printf(",%u,%u,%u)\r\n", 2, p[0], p[1]); 1791 } 1792 } 1793 1794 /* EPRT/EPSV */ 1795 { 1796 u_char af; 1797 1798 switch (su->su_family) { 1799 case AF_INET: 1800 af = 1; 1801 break; 1802 case AF_INET6: 1803 af = 2; 1804 break; 1805 default: 1806 af = 0; 1807 break; 1808 } 1809 if (af) { 1810 char hbuf[MAXHOSTNAMELEN], pbuf[10]; 1811 if (getnameinfo((struct sockaddr *)su, su->su_len, 1812 hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), 1813 NI_NUMERICHOST) == 0) { 1814 if (ispassive) 1815 printf("211- EPSV "); 1816 else 1817 printf("211- EPRT "); 1818 printf("(|%u|%s|%s|)\r\n", 1819 af, hbuf, pbuf); 1820 } 1821 } 1822 } 1823 } else 1824 printf(" No data connection\r\n"); 1825 reply(211, "End of status"); 1826} 1827 1828void 1829fatal(s) 1830 char *s; 1831{ 1832 1833 reply(451, "Error in server: %s\n", s); 1834 reply(221, "Closing connection due to server error."); 1835 dologout(0); 1836 /* NOTREACHED */ 1837} 1838 1839void 1840#ifdef __STDC__ 1841reply(int n, const char *fmt, ...) 1842#else 1843reply(n, fmt, va_alist) 1844 int n; 1845 char *fmt; 1846 va_dcl 1847#endif 1848{ 1849 char *buf, *p, *next; 1850 va_list ap; 1851#ifdef __STDC__ 1852 va_start(ap, fmt); 1853#else 1854 va_start(ap); 1855#endif 1856 if (vasprintf(&buf, fmt, ap) == -1 || buf == NULL) { 1857 printf("412 Local resource failure: malloc\r\n"); 1858 fflush(stdout); 1859 dologout(1); 1860 } 1861 next = buf; 1862 while ((p = strsep(&next, "\n\r"))) { 1863 printf("%d%s %s\r\n", n, (next != '\0') ? "-" : "", p); 1864 if (debug) 1865 syslog(LOG_DEBUG, "<--- %d%s %s", n, 1866 (next != '\0') ? "-" : "", p); 1867 } 1868 (void)fflush(stdout); 1869 free(buf); 1870 va_end(ap); 1871} 1872 1873void 1874#ifdef __STDC__ 1875lreply(int n, const char *fmt, ...) 1876#else 1877lreply(n, fmt, va_alist) 1878 int n; 1879 char *fmt; 1880 va_dcl 1881#endif 1882{ 1883 va_list ap; 1884#ifdef __STDC__ 1885 va_start(ap, fmt); 1886#else 1887 va_start(ap); 1888#endif 1889 (void)printf("%d- ", n); 1890 (void)vprintf(fmt, ap); 1891 va_end(ap); 1892 (void)printf("\r\n"); 1893 (void)fflush(stdout); 1894 if (debug) { 1895#ifdef __STDC__ 1896 va_start(ap, fmt); 1897#else 1898 va_start(ap); 1899#endif 1900 syslog(LOG_DEBUG, "<--- %d- ", n); 1901 vsyslog(LOG_DEBUG, fmt, ap); 1902 va_end(ap); 1903 } 1904} 1905 1906static void 1907ack(s) 1908 char *s; 1909{ 1910 1911 reply(250, "%s command successful.", s); 1912} 1913 1914void 1915nack(s) 1916 char *s; 1917{ 1918 1919 reply(502, "%s command not implemented.", s); 1920} 1921 1922/* ARGSUSED */ 1923void 1924yyerror(s) 1925 char *s; 1926{ 1927 char *cp; 1928 1929 if ((cp = strchr(cbuf,'\n'))) 1930 *cp = '\0'; 1931 reply(500, "'%s': command not understood.", cbuf); 1932} 1933 1934void 1935delete(name) 1936 char *name; 1937{ 1938 struct stat st; 1939 1940 LOGCMD("delete", name); 1941 if (stat(name, &st) < 0) { 1942 perror_reply(550, name); 1943 return; 1944 } 1945 if ((st.st_mode&S_IFMT) == S_IFDIR) { 1946 if (rmdir(name) < 0) { 1947 perror_reply(550, name); 1948 return; 1949 } 1950 goto done; 1951 } 1952 if (unlink(name) < 0) { 1953 perror_reply(550, name); 1954 return; 1955 } 1956done: 1957 ack("DELE"); 1958} 1959 1960void 1961cwd(path) 1962 char *path; 1963{ 1964 FILE *message; 1965 1966 if (chdir(path) < 0) 1967 perror_reply(550, path); 1968 else { 1969 if ((message = fopen(_PATH_CWDMESG, "r")) != NULL) { 1970 char *cp, line[LINE_MAX]; 1971 1972 while (fgets(line, sizeof(line), message) != NULL) { 1973 if ((cp = strchr(line, '\n')) != NULL) 1974 *cp = '\0'; 1975 lreply(250, "%s", line); 1976 } 1977 (void) fflush(stdout); 1978 (void) fclose(message); 1979 } 1980 ack("CWD"); 1981 } 1982} 1983 1984void 1985replydirname(name, message) 1986 const char *name, *message; 1987{ 1988 char *p, *ep; 1989 char npath[MAXPATHLEN * 2]; 1990 1991 p = npath; 1992 ep = &npath[sizeof(npath) - 1]; 1993 while (*name) { 1994 if (*name == '"') { 1995 if (ep - p < 2) 1996 break; 1997 *p++ = *name++; 1998 *p++ = '"'; 1999 } else { 2000 if (ep - p < 1) 2001 break; 2002 *p++ = *name++; 2003 } 2004 } 2005 *p = '\0'; 2006 reply(257, "\"%s\" %s", npath, message); 2007} 2008 2009void 2010makedir(name) 2011 char *name; 2012{ 2013 2014 LOGCMD("mkdir", name); 2015 if (mkdir(name, 0777) < 0) 2016 perror_reply(550, name); 2017 else 2018 replydirname(name, "directory created."); 2019} 2020 2021void 2022removedir(name) 2023 char *name; 2024{ 2025 2026 LOGCMD("rmdir", name); 2027 if (rmdir(name) < 0) 2028 perror_reply(550, name); 2029 else 2030 ack("RMD"); 2031} 2032 2033void 2034pwd() 2035{ 2036 char path[MAXPATHLEN]; 2037 2038 if (getcwd(path, sizeof(path)) == NULL) 2039 reply(550, "Can't get current directory: %s.", strerror(errno)); 2040 else 2041 replydirname(path, "is current directory."); 2042} 2043 2044char * 2045renamefrom(name) 2046 char *name; 2047{ 2048 struct stat st; 2049 2050 if (stat(name, &st) < 0) { 2051 perror_reply(550, name); 2052 return ((char *)0); 2053 } 2054 reply(350, "File exists, ready for destination name"); 2055 return (name); 2056} 2057 2058void 2059renamecmd(from, to) 2060 char *from, *to; 2061{ 2062 2063 LOGCMD2("rename", from, to); 2064 if (rename(from, to) < 0) 2065 perror_reply(550, "rename"); 2066 else 2067 ack("RNTO"); 2068} 2069 2070static void 2071dolog(sa) 2072 struct sockaddr *sa; 2073{ 2074 char hbuf[sizeof(remotehost)]; 2075 2076 getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), NULL, 0, 0); 2077 (void) strlcpy(remotehost, hbuf, sizeof(remotehost)); 2078 2079#ifdef HASSETPROCTITLE 2080 snprintf(proctitle, sizeof(proctitle), "%s: connected", remotehost); 2081 setproctitle("%s", proctitle); 2082#endif /* HASSETPROCTITLE */ 2083 2084 if (logging) 2085 syslog(LOG_INFO, "connection from %s", remotehost); 2086} 2087 2088/* 2089 * Record logout in wtmp file 2090 * and exit with supplied status. 2091 */ 2092void 2093dologout(status) 2094 int status; 2095{ 2096 2097 transflag = 0; 2098 2099 if (logged_in) { 2100 sigprocmask(SIG_BLOCK, &allsigs, NULL); 2101 (void) seteuid((uid_t)0); 2102 ftpdlogwtmp(ttyline, "", ""); 2103 if (doutmp) 2104 logout(utmp.ut_line); 2105 } 2106 /* beware of flushing buffers after a SIGPIPE */ 2107 _exit(status); 2108} 2109 2110static void 2111myoob(signo) 2112 int signo; 2113{ 2114 char *cp; 2115 int save_errno = errno; 2116 2117 /* XXX signal races GALORE */ 2118 2119 /* only process if transfer occurring */ 2120 if (!transflag) 2121 return; 2122 cp = tmpline; 2123 if (getline(cp, 7, stdin) == NULL) { 2124 reply(221, "You could at least say goodbye."); 2125 dologout(0); 2126 } 2127 upper(cp); 2128 if (strcmp(cp, "ABOR\r\n") == 0) { 2129 tmpline[0] = '\0'; 2130 reply(426, "Transfer aborted. Data connection closed."); 2131 reply(226, "Abort successful"); 2132 longjmp(urgcatch, 1); 2133 } 2134 if (strcmp(cp, "STAT\r\n") == 0) { 2135 tmpline[0] = '\0'; 2136 if (file_size != (off_t) -1) 2137 reply(213, "Status: %qd of %qd bytes transferred", 2138 byte_count, file_size); 2139 else 2140 reply(213, "Status: %qd bytes transferred", byte_count); 2141 } 2142 errno = save_errno; 2143} 2144 2145/* 2146 * Note: a response of 425 is not mentioned as a possible response to 2147 * the PASV command in RFC959. However, it has been blessed as 2148 * a legitimate response by Jon Postel in a telephone conversation 2149 * with Rick Adams on 25 Jan 89. 2150 */ 2151void 2152passive() 2153{ 2154 int len, on; 2155 u_char *p, *a; 2156 2157 if (pw == NULL) { 2158 reply(530, "Please login with USER and PASS"); 2159 return; 2160 } 2161 if (pdata >= 0) 2162 close(pdata); 2163 /* 2164 * XXX 2165 * At this point, it would be nice to have an algorithm that 2166 * inserted a growing delay in an attack scenario. Such a thing 2167 * would look like continual passive sockets being opened, but 2168 * nothing serious being done with them. They're not used to 2169 * move data; the entire attempt is just to use tcp FIN_WAIT 2170 * resources. 2171 */ 2172 pdata = socket(AF_INET, SOCK_STREAM, 0); 2173 if (pdata < 0) { 2174 perror_reply(425, "Can't open passive connection"); 2175 return; 2176 } 2177 2178#ifdef IP_PORTRANGE 2179 on = high_data_ports ? IP_PORTRANGE_HIGH : IP_PORTRANGE_DEFAULT; 2180 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2181 (char *)&on, sizeof(on)) < 0) 2182 goto pasv_error; 2183#endif 2184 2185 pasv_addr = ctrl_addr; 2186 pasv_addr.su_sin.sin_port = 0; 2187 if (bind(pdata, (struct sockaddr *)&pasv_addr, 2188 pasv_addr.su_len) < 0) 2189 goto pasv_error; 2190 2191 len = sizeof(pasv_addr); 2192 if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0) 2193 goto pasv_error; 2194 if (listen(pdata, 1) < 0) 2195 goto pasv_error; 2196 a = (u_char *) &pasv_addr.su_sin.sin_addr; 2197 p = (u_char *) &pasv_addr.su_sin.sin_port; 2198 2199 reply(227, "Entering Passive Mode (%u,%u,%u,%u,%u,%u)", a[0], 2200 a[1], a[2], a[3], p[0], p[1]); 2201 return; 2202 2203pasv_error: 2204 (void) seteuid((uid_t)pw->pw_uid); 2205 (void) close(pdata); 2206 pdata = -1; 2207 perror_reply(425, "Can't open passive connection"); 2208 return; 2209} 2210 2211/* 2212 * convert protocol identifier to/from AF 2213 */ 2214int 2215lpsvproto2af(int proto) 2216{ 2217 2218 switch (proto) { 2219 case 4: return AF_INET; 2220#ifdef INET6 2221 case 6: return AF_INET6; 2222#endif 2223 default: return -1; 2224 } 2225} 2226 2227int 2228af2lpsvproto(int af) 2229{ 2230 2231 switch (af) { 2232 case AF_INET: return 4; 2233#ifdef INET6 2234 case AF_INET6: return 6; 2235#endif 2236 default: return -1; 2237 } 2238} 2239 2240int 2241epsvproto2af(int proto) 2242{ 2243 2244 switch (proto) { 2245 case 1: return AF_INET; 2246#ifdef INET6 2247 case 2: return AF_INET6; 2248#endif 2249 default: return -1; 2250 } 2251} 2252 2253int 2254af2epsvproto(int af) 2255{ 2256 2257 switch (af) { 2258 case AF_INET: return 1; 2259#ifdef INET6 2260 case AF_INET6: return 2; 2261#endif 2262 default: return -1; 2263 } 2264} 2265 2266/* 2267 * 228 Entering Long Passive Mode (af, hal, h1, h2, h3,..., pal, p1, p2...) 2268 * 229 Entering Extended Passive Mode (|||port|) 2269 */ 2270void 2271long_passive(char *cmd, int pf) 2272{ 2273 int len, on; 2274 register u_char *p, *a; 2275 2276 if (!logged_in) { 2277 syslog(LOG_NOTICE, "long passive but not logged in"); 2278 reply(503, "Login with USER first."); 2279 return; 2280 } 2281 2282 if (pf != PF_UNSPEC && ctrl_addr.su_family != pf) { 2283 /* 2284 * XXX 2285 * only EPRT/EPSV ready clients will understand this 2286 */ 2287 if (strcmp(cmd, "EPSV") != 0) 2288 reply(501, "Network protocol mismatch"); /*XXX*/ 2289 else 2290 epsv_protounsupp("Network protocol mismatch"); 2291 2292 return; 2293 } 2294 2295 if (pdata >= 0) 2296 close(pdata); 2297 /* 2298 * XXX 2299 * At this point, it would be nice to have an algorithm that 2300 * inserted a growing delay in an attack scenario. Such a thing 2301 * would look like continual passive sockets being opened, but 2302 * nothing serious being done with them. They not used to move 2303 * data; the entire attempt is just to use tcp FIN_WAIT 2304 * resources. 2305 */ 2306 pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 2307 if (pdata < 0) { 2308 perror_reply(425, "Can't open passive connection"); 2309 return; 2310 } 2311 2312 switch (ctrl_addr.su_family) { 2313 case AF_INET: 2314#ifdef IP_PORTRANGE 2315 on = high_data_ports ? IP_PORTRANGE_HIGH : IP_PORTRANGE_DEFAULT; 2316 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2317 (char *)&on, sizeof(on)) < 0) 2318 goto pasv_error; 2319#endif 2320 break; 2321 case AF_INET6: 2322#ifdef IPV6_PORTRANGE 2323 on = high_data_ports ? IPV6_PORTRANGE_HIGH 2324 : IPV6_PORTRANGE_DEFAULT; 2325 if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE, 2326 (char *)&on, sizeof(on)) < 0) 2327 goto pasv_error; 2328#endif 2329 break; 2330 } 2331 2332 pasv_addr = ctrl_addr; 2333 pasv_addr.su_port = 0; 2334 (void) seteuid((uid_t) 0); 2335 if (bind(pdata, (struct sockaddr *) &pasv_addr, pasv_addr.su_len) < 0) { 2336 (void) seteuid((uid_t) pw->pw_uid); 2337 goto pasv_error; 2338 } 2339 (void) seteuid((uid_t) pw->pw_uid); 2340 len = pasv_addr.su_len; 2341 if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0) 2342 goto pasv_error; 2343 if (listen(pdata, 1) < 0) 2344 goto pasv_error; 2345 p = (u_char *) &pasv_addr.su_port; 2346 2347 if (strcmp(cmd, "LPSV") == 0) { 2348 switch (pasv_addr.su_family) { 2349 case AF_INET: 2350 a = (u_char *) &pasv_addr.su_sin.sin_addr; 2351 reply(228, 2352 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2353 4, 4, a[0], a[1], a[2], a[3], 2, p[0], p[1]); 2354 return; 2355 case AF_INET6: 2356 a = (char *) &pasv_addr.su_sin6.sin6_addr; 2357 reply(228, 2358 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u," 2359 "%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2360 6, 16, a[0], a[1], a[2], a[3], a[4], 2361 a[5], a[6], a[7], a[8], a[9], a[10], 2362 a[11], a[12], a[13], a[14], a[15], 2363 2, p[0], p[1]); 2364 return; 2365 } 2366 } else if (strcmp(cmd, "EPSV") == 0) { 2367 switch (pasv_addr.su_family) { 2368 case AF_INET: 2369 case AF_INET6: 2370 reply(229, "Entering Extended Passive Mode (|||%u|)", 2371 ntohs(pasv_addr.su_port)); 2372 return; 2373 } 2374 } else { 2375 /* more proper error code? */ 2376 } 2377 2378 pasv_error: 2379 (void) close(pdata); 2380 pdata = -1; 2381 perror_reply(425, "Can't open passive connection"); 2382 return; 2383} 2384 2385/* 2386 * EPRT |proto|addr|port| 2387 */ 2388int 2389extended_port(const char *arg) 2390{ 2391 char *tmp = NULL; 2392 char *result[3]; 2393 char *p, *q; 2394 char delim; 2395 struct addrinfo hints; 2396 struct addrinfo *res = NULL; 2397 int i; 2398 unsigned long proto; 2399 2400 if (epsvall) { 2401 reply(501, "EPRT disallowed after EPSV ALL"); 2402 return -1; 2403 } 2404 2405 usedefault = 0; 2406 if (pdata >= 0) { 2407 (void) close(pdata); 2408 pdata = -1; 2409 } 2410 2411 tmp = strdup(arg); 2412 if (!tmp) { 2413 fatal("not enough core."); 2414 /*NOTREACHED*/ 2415 } 2416 p = tmp; 2417 delim = p[0]; 2418 p++; 2419 memset(result, 0, sizeof(result)); 2420 for (i = 0; i < 3; i++) { 2421 q = strchr(p, delim); 2422 if (!q || *q != delim) 2423 goto parsefail; 2424 *q++ = '\0'; 2425 result[i] = p; 2426 p = q; 2427 } 2428 2429 /* some more sanity check */ 2430 p = NULL; 2431 (void)strtoul(result[2], &p, 10); 2432 if (!*result[2] || *p) 2433 goto protounsupp; 2434 p = NULL; 2435 proto = strtoul(result[0], &p, 10); 2436 if (!*result[0] || *p) 2437 goto protounsupp; 2438 2439 memset(&hints, 0, sizeof(hints)); 2440 hints.ai_family = epsvproto2af((int)proto); 2441 if (hints.ai_family < 0) 2442 goto protounsupp; 2443 hints.ai_socktype = SOCK_STREAM; 2444 hints.ai_flags = AI_NUMERICHOST; /*no DNS*/ 2445 if (getaddrinfo(result[1], result[2], &hints, &res)) 2446 goto parsefail; 2447 if (res->ai_next) 2448 goto parsefail; 2449 if (sizeof(data_dest) < res->ai_addrlen) 2450 goto parsefail; 2451 memcpy(&data_dest, res->ai_addr, res->ai_addrlen); 2452 if (his_addr.su_family == AF_INET6 && 2453 data_dest.su_family == AF_INET6) { 2454 /* XXX more sanity checks! */ 2455 data_dest.su_sin6.sin6_scope_id = 2456 his_addr.su_sin6.sin6_scope_id; 2457 } 2458 if (pdata >= 0) { 2459 (void) close(pdata); 2460 pdata = -1; 2461 } 2462 reply(200, "EPRT command successful."); 2463 2464 if (tmp) 2465 free(tmp); 2466 if (res) 2467 freeaddrinfo(res); 2468 return 0; 2469 2470parsefail: 2471 reply(500, "Invalid argument, rejected."); 2472 usedefault = 1; 2473 if (tmp) 2474 free(tmp); 2475 if (res) 2476 freeaddrinfo(res); 2477 return -1; 2478 2479protounsupp: 2480 epsv_protounsupp("Protocol not supported"); 2481 usedefault = 1; 2482 if (tmp) 2483 free(tmp); 2484 if (res) 2485 freeaddrinfo(res); 2486 return -1; 2487} 2488 2489/* 2490 * 522 Protocol not supported (proto,...) 2491 * as we assume address family for control and data connections are the same, 2492 * we do not return the list of address families we support - instead, we 2493 * return the address family of the control connection. 2494 */ 2495void 2496epsv_protounsupp(const char *message) 2497{ 2498 int proto; 2499 2500 proto = af2epsvproto(ctrl_addr.su_family); 2501 if (proto < 0) 2502 reply(501, "%s", message); /*XXX*/ 2503 else 2504 reply(522, "%s, use (%d)", message, proto); 2505} 2506 2507/* 2508 * Generate unique name for file with basename "local". 2509 * The file named "local" is already known to exist. 2510 * Generates failure reply on error. 2511 */ 2512static int 2513guniquefd(local, nam) 2514 char *local; 2515 char **nam; 2516{ 2517 static char new[MAXPATHLEN]; 2518 struct stat st; 2519 int count, len, fd; 2520 char *cp; 2521 2522 cp = strrchr(local, '/'); 2523 if (cp) 2524 *cp = '\0'; 2525 if (stat(cp ? local : ".", &st) < 0) { 2526 perror_reply(553, cp ? local : "."); 2527 return (-1); 2528 } 2529 if (cp) 2530 *cp = '/'; 2531 len = strlcpy(new, local, sizeof(new)); 2532 if (len+2+1 >= sizeof(new)-1) 2533 return (-1); 2534 cp = new + len; 2535 *cp++ = '.'; 2536 for (count = 1; count < 100; count++) { 2537 (void)snprintf(cp, sizeof(new) - (cp - new), "%d", count); 2538 fd = open(new, O_RDWR|O_CREAT|O_EXCL, 0666); 2539 if (fd == -1) 2540 continue; 2541 if (nam) 2542 *nam = new; 2543 return (fd); 2544 } 2545 reply(452, "Unique file name cannot be created."); 2546 return (-1); 2547} 2548 2549/* 2550 * Format and send reply containing system error number. 2551 */ 2552void 2553perror_reply(code, string) 2554 int code; 2555 char *string; 2556{ 2557 2558 reply(code, "%s: %s.", string, strerror(errno)); 2559} 2560 2561static char *onefile[] = { 2562 "", 2563 0 2564}; 2565 2566void 2567send_file_list(whichf) 2568 char *whichf; 2569{ 2570 struct stat st; 2571 DIR *dirp = NULL; 2572 struct dirent *dir; 2573 FILE *dout = NULL; 2574 char **dirlist; 2575 char *dirname; 2576 int simple = 0; 2577 volatile int freeglob = 0; 2578 glob_t gl; 2579 2580 if (strpbrk(whichf, "~{[*?") != NULL) { 2581 memset(&gl, 0, sizeof(gl)); 2582 freeglob = 1; 2583 if (glob(whichf, 2584 GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE|GLOB_LIMIT, 2585 0, &gl)) { 2586 reply(550, "not found"); 2587 goto out; 2588 } else if (gl.gl_pathc == 0) { 2589 errno = ENOENT; 2590 perror_reply(550, whichf); 2591 goto out; 2592 } 2593 dirlist = gl.gl_pathv; 2594 } else { 2595 onefile[0] = whichf; 2596 dirlist = onefile; 2597 simple = 1; 2598 } 2599 2600 if (setjmp(urgcatch)) { 2601 transflag = 0; 2602 goto out; 2603 } 2604 while ((dirname = *dirlist++)) { 2605 if (stat(dirname, &st) < 0) { 2606 /* 2607 * If user typed "ls -l", etc, and the client 2608 * used NLST, do what the user meant. 2609 */ 2610 if (dirname[0] == '-' && *dirlist == NULL && 2611 transflag == 0) { 2612 retrieve("/bin/ls %s", dirname); 2613 goto out; 2614 } 2615 perror_reply(550, whichf); 2616 if (dout != NULL) { 2617 (void) fclose(dout); 2618 transflag = 0; 2619 data = -1; 2620 pdata = -1; 2621 } 2622 goto out; 2623 } 2624 2625 if (S_ISREG(st.st_mode)) { 2626 if (dout == NULL) { 2627 dout = dataconn("file list", (off_t)-1, "w"); 2628 if (dout == NULL) 2629 goto out; 2630 transflag++; 2631 } 2632 fprintf(dout, "%s%s\n", dirname, 2633 type == TYPE_A ? "\r" : ""); 2634 byte_count += strlen(dirname) + 1; 2635 continue; 2636 } else if (!S_ISDIR(st.st_mode)) 2637 continue; 2638 2639 if ((dirp = opendir(dirname)) == NULL) 2640 continue; 2641 2642 while ((dir = readdir(dirp)) != NULL) { 2643 char nbuf[MAXPATHLEN]; 2644 2645 if (dir->d_name[0] == '.' && dir->d_namlen == 1) 2646 continue; 2647 if (dir->d_name[0] == '.' && dir->d_name[1] == '.' && 2648 dir->d_namlen == 2) 2649 continue; 2650 2651 snprintf(nbuf, sizeof(nbuf), "%s/%s", dirname, 2652 dir->d_name); 2653 2654 /* 2655 * We have to do a stat to insure it's 2656 * not a directory or special file. 2657 */ 2658 if (simple || (stat(nbuf, &st) == 0 && 2659 S_ISREG(st.st_mode))) { 2660 if (dout == NULL) { 2661 dout = dataconn("file list", (off_t)-1, 2662 "w"); 2663 if (dout == NULL) 2664 goto out; 2665 transflag++; 2666 } 2667 if (nbuf[0] == '.' && nbuf[1] == '/') 2668 fprintf(dout, "%s%s\n", &nbuf[2], 2669 type == TYPE_A ? "\r" : ""); 2670 else 2671 fprintf(dout, "%s%s\n", nbuf, 2672 type == TYPE_A ? "\r" : ""); 2673 byte_count += strlen(nbuf) + 1; 2674 } 2675 } 2676 (void) closedir(dirp); 2677 } 2678 2679 if (dout == NULL) 2680 reply(550, "No files found."); 2681 else if (ferror(dout) != 0) 2682 perror_reply(550, "Data connection"); 2683 else 2684 reply(226, "Transfer complete."); 2685 2686 transflag = 0; 2687 if (dout != NULL) 2688 (void) fclose(dout); 2689 else { 2690 if (pdata >= 0) 2691 close(pdata); 2692 } 2693 data = -1; 2694 pdata = -1; 2695out: 2696 if (freeglob) { 2697 freeglob = 0; 2698 globfree(&gl); 2699 } 2700} 2701 2702static void 2703reapchild(signo) 2704 int signo; 2705{ 2706 int save_errno = errno; 2707 2708 while (wait3(NULL, WNOHANG, NULL) > 0) 2709 ; 2710 errno = save_errno; 2711} 2712 2713void 2714logxfer(name, size, start) 2715 char *name; 2716 off_t size; 2717 time_t start; 2718{ 2719 char buf[400 + MAXHOSTNAMELEN*4 + MAXPATHLEN*4]; 2720 char dir[MAXPATHLEN], path[MAXPATHLEN], rpath[MAXPATHLEN]; 2721 char vremotehost[MAXHOSTNAMELEN*4], vpath[MAXPATHLEN*4]; 2722 char *vpw; 2723 time_t now; 2724 int len; 2725 2726 if ((statfd >= 0) && (getcwd(dir, sizeof(dir)) != NULL)) { 2727 time(&now); 2728 2729 vpw = malloc(strlen(guest ? guestpw : pw->pw_name) * 4 + 1); 2730 if (vpw == NULL) 2731 return; 2732 2733 snprintf(path, sizeof(path), "%s/%s", dir, name); 2734 if (realpath(path, rpath) == NULL) 2735 strlcpy(rpath, path, sizeof(rpath)); 2736 strvis(vpath, rpath, VIS_SAFE|VIS_NOSLASH); 2737 2738 strvis(vremotehost, remotehost, VIS_SAFE|VIS_NOSLASH); 2739 strvis(vpw, guest? guestpw : pw->pw_name, VIS_SAFE|VIS_NOSLASH); 2740 2741 len = snprintf(buf, sizeof(buf), 2742 "%.24s %d %s %qd %s %c %s %c %c %s ftp %d %s %s\n", 2743 ctime(&now), now - start + (now == start), 2744 vremotehost, (long long) size, vpath, 2745 ((type == TYPE_A) ? 'a' : 'b'), "*" /* none yet */, 2746 'o', ((guest) ? 'a' : 'r'), 2747 vpw, 0 /* none yet */, 2748 ((guest) ? "*" : pw->pw_name), dhostname); 2749 if (len >= sizeof(buf)) { 2750 len = sizeof(buf); 2751 buf[sizeof(buf) - 1] = '\n'; 2752 } 2753 write(statfd, buf, len); 2754 free(vpw); 2755 } 2756} 2757 2758#if defined(TCPWRAPPERS) 2759static int 2760check_host(sa) 2761 struct sockaddr *sa; 2762{ 2763 struct sockaddr_in *sin; 2764 struct hostent *hp; 2765 char *addr; 2766 2767 if (sa->sa_family != AF_INET) 2768 return 1; /*XXX*/ 2769 2770 sin = (struct sockaddr_in *)sa; 2771 hp = gethostbyaddr((char *)&sin->sin_addr, 2772 sizeof(struct in_addr), AF_INET); 2773 addr = inet_ntoa(sin->sin_addr); 2774 if (hp) { 2775 if (!hosts_ctl("ftpd", hp->h_name, addr, STRING_UNKNOWN)) { 2776 syslog(LOG_NOTICE, "tcpwrappers rejected: %s [%s]", 2777 hp->h_name, addr); 2778 return (0); 2779 } 2780 } else { 2781 if (!hosts_ctl("ftpd", STRING_UNKNOWN, addr, STRING_UNKNOWN)) { 2782 syslog(LOG_NOTICE, "tcpwrappers rejected: [%s]", addr); 2783 return (0); 2784 } 2785 } 2786 return (1); 2787} 2788#endif /* TCPWRAPPERS */ 2789 2790/* 2791 * Allocate space and return a copy of the specified dir. 2792 * If 'dir' begins with a tilde (~), expand it. 2793 */ 2794char * 2795copy_dir(dir, pw) 2796 char *dir; 2797 struct passwd *pw; 2798{ 2799 char *cp; 2800 char *newdir; 2801 char *user = NULL; 2802 size_t dirsiz; 2803 2804 /* Nothing to expand */ 2805 if (dir[0] != '~') 2806 return (strdup(dir)); 2807 2808 /* "dir" is of form ~user/some/dir, lookup user. */ 2809 if (dir[1] != '/' && dir[1] != '\0') { 2810 if ((cp = strchr(dir + 1, '/')) == NULL) 2811 cp = dir + strlen(dir); 2812 if ((user = malloc(cp - dir)) == NULL) 2813 return (NULL); 2814 strlcpy(user, dir + 1, cp - dir); 2815 2816 /* Only do lookup if it is a different user. */ 2817 if (strcmp(user, pw->pw_name) != 0) { 2818 if ((pw = getpwnam(user)) == NULL) { 2819 /* No such user, interpret literally */ 2820 free(user); 2821 return(strdup(dir)); 2822 } 2823 } 2824 } 2825 2826 /* 2827 * If there is no directory separator (/) then it is just pw_dir. 2828 * Otherwise, replace ~foo with pw_dir. 2829 */ 2830 if ((cp = strchr(dir + 1, '/')) == NULL) { 2831 newdir = strdup(pw->pw_dir); 2832 } else { 2833 dirsiz = strlen(cp) + strlen(pw->pw_dir) + 1; 2834 if ((newdir = malloc(dirsiz)) == NULL) 2835 return (NULL); 2836 strcpy(newdir, pw->pw_dir); 2837 strcat(newdir, cp); 2838 } 2839 2840 if (user) 2841 free(user); 2842 return(newdir); 2843} 2844