ftpd.c revision 1.139
1/* $OpenBSD: ftpd.c,v 1.139 2002/11/25 22:45:39 millert Exp $ */ 2/* $NetBSD: ftpd.c,v 1.15 1995/06/03 22:46:47 mycroft Exp $ */ 3 4/* 5 * Copyright (C) 1997 and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33/* 34 * Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. 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 const 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 const char sccsid[] = "@(#)ftpd.c 8.4 (Berkeley) 4/16/94"; 75#else 76static const char rcsid[] = 77 "$OpenBSD: ftpd.c,v 1.139 2002/11/25 22:45:39 millert Exp $"; 78#endif 79#endif /* not lint */ 80 81/* 82 * FTP server. 83 */ 84#include <sys/param.h> 85#include <sys/stat.h> 86#include <sys/ioctl.h> 87#include <sys/socket.h> 88#include <sys/wait.h> 89#include <sys/mman.h> 90 91#include <netinet/in.h> 92#include <netinet/in_systm.h> 93#include <netinet/ip.h> 94#include <netinet/tcp.h> 95 96#define FTP_NAMES 97#include <arpa/ftp.h> 98#include <arpa/inet.h> 99#include <arpa/telnet.h> 100 101#include <bsd_auth.h> 102#include <ctype.h> 103#include <dirent.h> 104#include <err.h> 105#include <errno.h> 106#include <fcntl.h> 107#include <glob.h> 108#include <limits.h> 109#include <login_cap.h> 110#include <netdb.h> 111#include <pwd.h> 112#include <signal.h> 113#include <stdarg.h> 114#include <stdio.h> 115#include <stdlib.h> 116#include <string.h> 117#include <syslog.h> 118#include <time.h> 119#include <vis.h> 120#include <unistd.h> 121#include <util.h> 122#include <utmp.h> 123 124#if defined(TCPWRAPPERS) 125#include <tcpd.h> 126#endif /* TCPWRAPPERS */ 127 128#include "pathnames.h" 129#include "extern.h" 130 131static char version[] = "Version 6.5/OpenBSD"; 132 133extern off_t restart_point; 134extern char cbuf[]; 135 136union sockunion server_addr; 137union sockunion ctrl_addr; 138union sockunion data_source; 139union sockunion data_dest; 140union sockunion his_addr; 141union sockunion pasv_addr; 142 143sigset_t allsigs; 144 145int daemon_mode = 0; 146int data; 147int logged_in; 148struct passwd *pw; 149int debug = 0; 150int timeout = 900; /* timeout after 15 minutes of inactivity */ 151int maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */ 152int logging; 153int anon_ok = 1; 154int anon_only = 0; 155int multihome = 0; 156int guest; 157int stats; 158int statfd = -1; 159int portcheck = 1; 160int dochroot; 161int type; 162int form; 163int stru; /* avoid C keyword */ 164int mode; 165int doutmp = 0; /* update utmp file */ 166int usedefault = 1; /* for data transfers */ 167int pdata = -1; /* for passive mode */ 168int family = AF_INET; 169volatile sig_atomic_t transflag; 170off_t file_size; 171off_t byte_count; 172#if !defined(CMASK) || CMASK == 0 173#undef CMASK 174#define CMASK 022 175#endif 176int defumask = CMASK; /* default umask value */ 177int umaskchange = 1; /* allow user to change umask value. */ 178char tmpline[7]; 179char hostname[MAXHOSTNAMELEN]; 180char remotehost[MAXHOSTNAMELEN]; 181char dhostname[MAXHOSTNAMELEN]; 182char *guestpw; 183static char ttyline[20]; 184char *tty = ttyline; /* for klogin */ 185static struct utmp utmp; /* for utmp */ 186static login_cap_t *lc; 187static auth_session_t *as; 188static volatile sig_atomic_t recvurg; 189 190#if defined(TCPWRAPPERS) 191int allow_severity = LOG_INFO; 192int deny_severity = LOG_NOTICE; 193#endif /* TCPWRAPPERS */ 194 195char *ident = NULL; 196 197 198int epsvall = 0; 199 200/* 201 * Timeout intervals for retrying connections 202 * to hosts that don't accept PORT cmds. This 203 * is a kludge, but given the problems with TCP... 204 */ 205#define SWAITMAX 90 /* wait at most 90 seconds */ 206#define SWAITINT 5 /* interval between retries */ 207 208int swaitmax = SWAITMAX; 209int swaitint = SWAITINT; 210 211#ifdef HASSETPROCTITLE 212char proctitle[BUFSIZ]; /* initial part of title */ 213#endif /* HASSETPROCTITLE */ 214 215#define LOGCMD(cmd, file) \ 216 if (logging > 1) \ 217 syslog(LOG_INFO,"%s %s%s", cmd, \ 218 *(file) == '/' ? "" : curdir(), file); 219#define LOGCMD2(cmd, file1, file2) \ 220 if (logging > 1) \ 221 syslog(LOG_INFO,"%s %s%s %s%s", cmd, \ 222 *(file1) == '/' ? "" : curdir(), file1, \ 223 *(file2) == '/' ? "" : curdir(), file2); 224#define LOGBYTES(cmd, file, cnt) \ 225 if (logging > 1) { \ 226 if (cnt == (off_t)-1) \ 227 syslog(LOG_INFO,"%s %s%s", cmd, \ 228 *(file) == '/' ? "" : curdir(), file); \ 229 else \ 230 syslog(LOG_INFO, "%s %s%s = %qd bytes", \ 231 cmd, (*(file) == '/') ? "" : curdir(), file, cnt); \ 232 } 233 234static void ack(char *); 235static void sigurg(int); 236static void myoob(void); 237static int checkuser(char *, char *); 238static FILE *dataconn(char *, off_t, char *); 239static void dolog(struct sockaddr *); 240static char *copy_dir(char *, struct passwd *); 241static char *curdir(void); 242static void end_login(void); 243static FILE *getdatasock(char *); 244static int guniquefd(char *, char **); 245static void lostconn(int); 246static void sigquit(int); 247static int receive_data(FILE *, FILE *); 248static void replydirname(const char *, const char *); 249static int send_data(FILE *, FILE *, off_t, off_t, int); 250static struct passwd * 251 sgetpwnam(char *); 252static void reapchild(int); 253#if defined(TCPWRAPPERS) 254static int check_host(struct sockaddr *); 255#endif /* TCPWRAPPERS */ 256static void usage(void); 257 258void logxfer(char *, off_t, time_t); 259 260static char * 261curdir() 262{ 263 static char path[MAXPATHLEN+1]; /* path + '/' */ 264 265 if (getcwd(path, sizeof(path)-1) == NULL) 266 return (""); 267 if (path[1] != '\0') /* special case for root dir. */ 268 strlcat(path, "/", sizeof path); 269 /* For guest account, skip / since it's chrooted */ 270 return (guest ? path+1 : path); 271} 272 273char *argstr = "AdDhnlMSt:T:u:UvP46"; 274 275static void 276usage() 277{ 278 syslog(LOG_ERR, 279 "usage: ftpd [-AdDhlMPSU46] [-t timeout] [-T maxtimeout] [-u mask]"); 280 exit(2); 281} 282 283int 284main(argc, argv, envp) 285 int argc; 286 char *argv[]; 287 char **envp; 288{ 289 socklen_t addrlen; 290 int ch, on = 1, tos; 291 char *cp, line[LINE_MAX]; 292 FILE *fp; 293 struct hostent *hp; 294 struct sigaction sa; 295 296 tzset(); /* in case no timezone database in ~ftp */ 297 sigfillset(&allsigs); /* used to block signals while root */ 298 sigemptyset(&sa.sa_mask); 299 sa.sa_flags = SA_RESTART; 300 301 while ((ch = getopt(argc, argv, argstr)) != -1) { 302 switch (ch) { 303 case 'A': 304 anon_only = 1; 305 break; 306 307 case 'd': 308 case 'v': /* deprecated */ 309 debug = 1; 310 break; 311 312 case 'D': 313 daemon_mode = 1; 314 break; 315 316 case 'P': 317 portcheck = 0; 318 break; 319 320 case 'h': /* deprecated */ 321 break; 322 323 case 'l': 324 logging++; /* > 1 == extra logging */ 325 break; 326 327 case 'M': 328 multihome = 1; 329 break; 330 331 case 'n': 332 anon_ok = 0; 333 break; 334 335 case 'S': 336 stats = 1; 337 break; 338 339 case 't': 340 timeout = atoi(optarg); 341 if (maxtimeout < timeout) 342 maxtimeout = timeout; 343 break; 344 345 case 'T': 346 maxtimeout = atoi(optarg); 347 if (timeout > maxtimeout) 348 timeout = maxtimeout; 349 break; 350 351 case 'u': 352 { 353 long val = 0; 354 char *p; 355 umaskchange = 0; 356 357 val = strtol(optarg, &p, 8); 358 if (*p != '\0' || val < 0 || (val & ~ACCESSPERMS)) { 359 syslog(LOG_ERR, 360 "ftpd: %s is a bad value for -u, aborting..", 361 optarg); 362 exit(2); 363 } else 364 defumask = val; 365 break; 366 } 367 368 case 'U': 369 doutmp = 1; 370 break; 371 372 case '4': 373 family = AF_INET; 374 break; 375 376 case '6': 377 family = AF_INET6; 378 break; 379 380 default: 381 usage(); 382 break; 383 } 384 } 385 386 (void) freopen(_PATH_DEVNULL, "w", stderr); 387 388 /* 389 * LOG_NDELAY sets up the logging connection immediately, 390 * necessary for anonymous ftp's that chroot and can't do it later. 391 */ 392 openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP); 393 394 if (daemon_mode) { 395 int ctl_sock, fd; 396 struct servent *sv; 397 398 /* 399 * Detach from parent. 400 */ 401 if (daemon(1, 1) < 0) { 402 syslog(LOG_ERR, "failed to become a daemon"); 403 exit(1); 404 } 405 sa.sa_handler = reapchild; 406 (void) sigaction(SIGCHLD, &sa, NULL); 407 /* 408 * Get port number for ftp/tcp. 409 */ 410 sv = getservbyname("ftp", "tcp"); 411 if (sv == NULL) { 412 syslog(LOG_ERR, "getservbyname for ftp failed"); 413 exit(1); 414 } 415 /* 416 * Open a socket, bind it to the FTP port, and start 417 * listening. 418 */ 419 ctl_sock = socket(family, SOCK_STREAM, 0); 420 if (ctl_sock < 0) { 421 syslog(LOG_ERR, "control socket: %m"); 422 exit(1); 423 } 424 if (setsockopt(ctl_sock, SOL_SOCKET, SO_REUSEADDR, 425 (char *)&on, sizeof(on)) < 0) 426 syslog(LOG_ERR, "control setsockopt: %m"); 427 memset(&server_addr, 0, sizeof(server_addr)); 428 server_addr.su_sin.sin_family = family; 429 switch (family) { 430 case AF_INET: 431 server_addr.su_len = sizeof(struct sockaddr_in); 432 server_addr.su_sin.sin_port = sv->s_port; 433 break; 434 case AF_INET6: 435 server_addr.su_len = sizeof(struct sockaddr_in6); 436 server_addr.su_sin6.sin6_port = sv->s_port; 437 break; 438 } 439 if (bind(ctl_sock, (struct sockaddr *)&server_addr, 440 server_addr.su_len)) { 441 syslog(LOG_ERR, "control bind: %m"); 442 exit(1); 443 } 444 if (listen(ctl_sock, 32) < 0) { 445 syslog(LOG_ERR, "control listen: %m"); 446 exit(1); 447 } 448 /* Stash pid in pidfile */ 449 if (pidfile(NULL)) 450 syslog(LOG_ERR, "can't open pidfile: %m"); 451 /* 452 * Loop forever accepting connection requests and forking off 453 * children to handle them. 454 */ 455 while (1) { 456 addrlen = sizeof(his_addr); 457 fd = accept(ctl_sock, (struct sockaddr *)&his_addr, 458 &addrlen); 459 if (fork() == 0) { 460 /* child */ 461 (void) dup2(fd, 0); 462 (void) dup2(fd, 1); 463 close(ctl_sock); 464 break; 465 } 466 close(fd); 467 } 468 469#if defined(TCPWRAPPERS) 470 /* ..in the child. */ 471 if (!check_host((struct sockaddr *)&his_addr)) 472 exit(1); 473#endif /* TCPWRAPPERS */ 474 } else { 475 addrlen = sizeof(his_addr); 476 if (getpeername(0, (struct sockaddr *)&his_addr, 477 &addrlen) < 0) { 478 /* syslog(LOG_ERR, "getpeername (%s): %m", argv[0]); */ 479 exit(1); 480 } 481 } 482 483 /* set this here so klogin can use it... */ 484 (void)snprintf(ttyline, sizeof(ttyline), "ftp%ld", (long)getpid()); 485 486 sa.sa_handler = SIG_DFL; 487 (void) sigaction(SIGCHLD, &sa, NULL); 488 489 sa.sa_handler = sigurg; 490 sa.sa_flags = 0; /* don't restart syscalls for SIGURG */ 491 (void) sigaction(SIGURG, &sa, NULL); 492 493 sigfillset(&sa.sa_mask); /* block all signals in handler */ 494 sa.sa_flags = SA_RESTART; 495 sa.sa_handler = sigquit; 496 (void) sigaction(SIGHUP, &sa, NULL); 497 (void) sigaction(SIGINT, &sa, NULL); 498 (void) sigaction(SIGQUIT, &sa, NULL); 499 (void) sigaction(SIGTERM, &sa, NULL); 500 501 sa.sa_handler = lostconn; 502 (void) sigaction(SIGPIPE, &sa, NULL); 503 504 sa.sa_handler = toolong; 505 (void) sigaction(SIGALRM, &sa, NULL); 506 507 addrlen = sizeof(ctrl_addr); 508 if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) { 509 syslog(LOG_ERR, "getsockname: %m"); 510 exit(1); 511 } 512 if (his_addr.su_family == AF_INET6 513 && IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr)) { 514#if 1 515 /* 516 * IPv4 control connection arrived to AF_INET6 socket. 517 * I hate to do this, but this is the easiest solution. 518 */ 519 union sockunion tmp_addr; 520 const int off = sizeof(struct in6_addr) - sizeof(struct in_addr); 521 522 tmp_addr = his_addr; 523 memset(&his_addr, 0, sizeof(his_addr)); 524 his_addr.su_sin.sin_family = AF_INET; 525 his_addr.su_sin.sin_len = sizeof(his_addr.su_sin); 526 memcpy(&his_addr.su_sin.sin_addr, 527 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 528 sizeof(his_addr.su_sin.sin_addr)); 529 his_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 530 531 tmp_addr = ctrl_addr; 532 memset(&ctrl_addr, 0, sizeof(ctrl_addr)); 533 ctrl_addr.su_sin.sin_family = AF_INET; 534 ctrl_addr.su_sin.sin_len = sizeof(ctrl_addr.su_sin); 535 memcpy(&ctrl_addr.su_sin.sin_addr, 536 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 537 sizeof(ctrl_addr.su_sin.sin_addr)); 538 ctrl_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 539#else 540 while (fgets(line, sizeof(line), fd) != NULL) { 541 if ((cp = strchr(line, '\n')) != NULL) 542 *cp = '\0'; 543 lreply(530, "%s", line); 544 } 545 (void) fflush(stdout); 546 (void) fclose(fd); 547 reply(530, 548 "Connection from IPv4 mapped address is not supported."); 549 exit(0); 550#endif 551 } 552#ifdef IP_TOS 553 if (his_addr.su_family == AF_INET) { 554 tos = IPTOS_LOWDELAY; 555 if (setsockopt(0, IPPROTO_IP, IP_TOS, (char *)&tos, 556 sizeof(int)) < 0) 557 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 558 } 559#endif 560 data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1); 561 562 /* Try to handle urgent data inline */ 563#ifdef SO_OOBINLINE 564 if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, (char *)&on, sizeof(on)) < 0) 565 syslog(LOG_ERR, "setsockopt: %m"); 566#endif 567 568#ifdef F_SETOWN 569 if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1) 570 syslog(LOG_ERR, "fcntl F_SETOWN: %m"); 571#endif 572 dolog((struct sockaddr *)&his_addr); 573 /* 574 * Set up default state 575 */ 576 data = -1; 577 type = TYPE_A; 578 form = FORM_N; 579 stru = STRU_F; 580 mode = MODE_S; 581 tmpline[0] = '\0'; 582 583 /* If logins are disabled, print out the message. */ 584 if ((fp = fopen(_PATH_NOLOGIN, "r")) != NULL) { 585 while (fgets(line, sizeof(line), fp) != NULL) { 586 if ((cp = strchr(line, '\n')) != NULL) 587 *cp = '\0'; 588 lreply(530, "%s", line); 589 } 590 (void) fflush(stdout); 591 (void) fclose(fp); 592 reply(530, "System not available."); 593 exit(0); 594 } 595 if ((fp = fopen(_PATH_FTPWELCOME, "r")) != NULL) { 596 while (fgets(line, sizeof(line), fp) != NULL) { 597 if ((cp = strchr(line, '\n')) != NULL) 598 *cp = '\0'; 599 lreply(220, "%s", line); 600 } 601 (void) fflush(stdout); 602 (void) fclose(fp); 603 /* reply(220,) must follow */ 604 } 605 (void) gethostname(hostname, sizeof(hostname)); 606 607 /* Make sure hostname is fully qualified. */ 608 hp = gethostbyname(hostname); 609 if (hp != NULL) 610 strlcpy(hostname, hp->h_name, sizeof(hostname)); 611 612 if (multihome) { 613 getnameinfo((struct sockaddr *)&ctrl_addr, ctrl_addr.su_len, 614 dhostname, sizeof(dhostname), NULL, 0, 0); 615 } 616 617 reply(220, "%s FTP server (%s) ready.", 618 (multihome ? dhostname : hostname), version); 619 for (;;) 620 (void) yyparse(); 621 /* NOTREACHED */ 622} 623 624/* 625 * Signal handlers. 626 */ 627 628static void 629lostconn(signo) 630 int signo; 631{ 632 struct syslog_data sdata = SYSLOG_DATA_INIT; 633 634 if (debug) 635 syslog_r(LOG_DEBUG, &sdata, "lost connection"); 636 dologout(1); 637} 638 639static void 640sigquit(signo) 641 int signo; 642{ 643 struct syslog_data sdata = SYSLOG_DATA_INIT; 644 645 syslog_r(LOG_ERR, &sdata, "got signal %s", sys_signame[signo]); 646 dologout(1); 647} 648 649/* 650 * Save the result of a getpwnam. Used for USER command, since 651 * the data returned must not be clobbered by any other command 652 * (e.g., globbing). 653 */ 654static struct passwd * 655sgetpwnam(name) 656 char *name; 657{ 658 static struct passwd *save; 659 struct passwd *pw; 660 661 if ((pw = getpwnam(name)) == NULL) 662 return (NULL); 663 if (save) { 664 memset(save->pw_passwd, 0, strlen(save->pw_passwd)); 665 free(save); 666 } 667 save = pw_dup(pw); 668 if (save == NULL) { 669 perror_reply(421, "Local resource failure: malloc"); 670 dologout(1); 671 /* NOTREACHED */ 672 } 673 return (save); 674} 675 676static int login_attempts; /* number of failed login attempts */ 677static int askpasswd; /* had user command, ask for passwd */ 678static char curname[MAXLOGNAME]; /* current USER name */ 679 680/* 681 * USER command. 682 * Sets global passwd pointer pw if named account exists and is acceptable; 683 * sets askpasswd if a PASS command is expected. If logged in previously, 684 * need to reset state. If name is "ftp" or "anonymous", the name is not in 685 * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return. 686 * If account doesn't exist, ask for passwd anyway. Otherwise, check user 687 * requesting login privileges. Disallow anyone who does not have a standard 688 * shell as returned by getusershell(). Disallow anyone mentioned in the file 689 * _PATH_FTPUSERS to allow people such as root and uucp to be avoided. 690 */ 691void 692user(name) 693 char *name; 694{ 695 char *cp, *shell, *style, *host; 696 char *class = NULL; 697 698 if (logged_in) 699 end_login(); 700 701 /* Close session from previous user if there was one. */ 702 if (as) { 703 auth_close(as); 704 as = NULL; 705 } 706 if (lc) { 707 login_close(lc); 708 lc = NULL; 709 } 710 711 if ((style = strchr(name, ':')) != NULL) 712 *style++ = 0; 713 714 guest = 0; 715 host = multihome ? dhostname : hostname; 716 if (anon_ok && 717 (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, "%s", 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 if (logged_in) { 858 ftpdlogwtmp(ttyline, "", ""); 859 if (doutmp) 860 logout(utmp.ut_line); 861 } 862 reply(530, "Please reconnect to work as another user"); 863 exit(0); 864} 865 866void 867pass(passwd) 868 char *passwd; 869{ 870 int authok, flags; 871 FILE *fp; 872 static char homedir[MAXPATHLEN]; 873 char *motd, *dir, rootdir[MAXPATHLEN]; 874 875 if (logged_in || askpasswd == 0) { 876 reply(503, "Login with USER first."); 877 return; 878 } 879 askpasswd = 0; 880 if (!guest) { /* "ftp" is only account allowed no password */ 881 authok = 0; 882 if (pw == NULL || pw->pw_passwd[0] == '\0') { 883 useconds_t us; 884 885 /* Sleep between 1 and 3 seconds to emulate a crypt. */ 886 us = arc4random() % 3000000; 887 usleep(us); 888 if (as != NULL) { 889 auth_close(as); 890 as = NULL; 891 } 892 } else { 893 authok = auth_userresponse(as, passwd, 0); 894 as = NULL; 895 } 896 if (authok == 0) { 897 reply(530, "Login incorrect."); 898 if (logging) 899 syslog(LOG_NOTICE, 900 "FTP LOGIN FAILED FROM %s, %s", 901 remotehost, curname); 902 pw = NULL; 903 if (login_attempts++ >= 5) { 904 syslog(LOG_NOTICE, 905 "repeated login failures from %s", 906 remotehost); 907 exit(0); 908 } 909 return; 910 } 911 } else if (lc != NULL) { 912 /* Save anonymous' password. */ 913 if (guestpw != NULL) 914 free(guestpw); 915 guestpw = strdup(passwd); 916 if (guestpw == NULL) 917 fatal("Out of memory."); 918 919 authok = auth_approval(as, lc, pw->pw_name, "ftp"); 920 auth_close(as); 921 as = NULL; 922 if (authok == 0) { 923 syslog(LOG_INFO|LOG_AUTH, 924 "FTP LOGIN FAILED (HOST) as %s: approval failure.", 925 pw->pw_name); 926 reply(530, "Approval failure."); 927 exit(0); 928 } 929 } else { 930 syslog(LOG_INFO|LOG_AUTH, 931 "FTP LOGIN CLASS %s MISSING for %s: approval failure.", 932 pw->pw_class, pw->pw_name); 933 reply(530, "Permission denied."); 934 exit(0); 935 } 936 login_attempts = 0; /* this time successful */ 937 /* set umask via setusercontext() unless -u flag was given. */ 938 flags = LOGIN_SETGROUP|LOGIN_SETPRIORITY|LOGIN_SETRESOURCES; 939 if (umaskchange) 940 flags |= LOGIN_SETUMASK; 941 else 942 (void) umask(defumask); 943 if (setusercontext(lc, pw, (uid_t)0, flags) != 0) { 944 perror_reply(451, "Local resource failure: setusercontext"); 945 syslog(LOG_NOTICE, "setusercontext: %m"); 946 dologout(1); 947 /* NOTREACHED */ 948 } 949 950 /* open wtmp before chroot */ 951 ftpdlogwtmp(ttyline, pw->pw_name, remotehost); 952 953 /* open utmp before chroot */ 954 if (doutmp) { 955 memset((void *)&utmp, 0, sizeof(utmp)); 956 (void)time(&utmp.ut_time); 957 (void)strncpy(utmp.ut_name, pw->pw_name, sizeof(utmp.ut_name)); 958 (void)strncpy(utmp.ut_host, remotehost, sizeof(utmp.ut_host)); 959 (void)strncpy(utmp.ut_line, ttyline, sizeof(utmp.ut_line)); 960 login(&utmp); 961 } 962 963 /* open stats file before chroot */ 964 if (guest && (stats == 1) && (statfd < 0)) 965 if ((statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND)) < 0) 966 stats = 0; 967 968 logged_in = 1; 969 970 if ((dir = login_getcapstr(lc, "ftp-dir", NULL, NULL))) { 971 char *newdir; 972 973 newdir = copy_dir(dir, pw); 974 if (newdir == NULL) { 975 perror_reply(421, "Local resource failure: malloc"); 976 dologout(1); 977 /* NOTREACHED */ 978 } 979 free(dir); 980 free(pw->pw_dir); 981 pw->pw_dir = newdir; 982 } 983 984 /* make sure pw->pw_dir is big enough to hold "/" */ 985 if (strlen(pw->pw_dir) < 1) { 986 char *newdir; 987 988 newdir = malloc(2); 989 if (newdir == NULL) { 990 perror_reply(421, "Local resource failure: malloc"); 991 dologout(1); 992 /* NOTREACHED */ 993 } 994 strlcpy(newdir, pw->pw_dir, 2); 995 free(pw->pw_dir); 996 pw->pw_dir = newdir; 997 } 998 999 if (guest || dochroot) { 1000 if (multihome && guest) { 1001 struct stat ts; 1002 1003 /* Compute root directory. */ 1004 snprintf(rootdir, sizeof(rootdir), "%s/%s", 1005 pw->pw_dir, dhostname); 1006 if (stat(rootdir, &ts) < 0) { 1007 snprintf(rootdir, sizeof(rootdir), "%s/%s", 1008 pw->pw_dir, hostname); 1009 } 1010 } else 1011 strlcpy(rootdir, pw->pw_dir, sizeof(rootdir)); 1012 } 1013 if (guest) { 1014 /* 1015 * We MUST do a chdir() after the chroot. Otherwise 1016 * the old current directory will be accessible as "." 1017 * outside the new root! 1018 */ 1019 if (chroot(rootdir) < 0 || chdir("/") < 0) { 1020 reply(550, "Can't set guest privileges."); 1021 goto bad; 1022 } 1023 strcpy(pw->pw_dir, "/"); 1024 if (setenv("HOME", "/", 1) == -1) { 1025 reply(550, "Can't setup environment."); 1026 goto bad; 1027 } 1028 } else if (dochroot) { 1029 if (chroot(rootdir) < 0 || chdir("/") < 0) { 1030 reply(550, "Can't change root."); 1031 goto bad; 1032 } 1033 strcpy(pw->pw_dir, "/"); 1034 if (setenv("HOME", "/", 1) == -1) { 1035 reply(550, "Can't setup environment."); 1036 goto bad; 1037 } 1038 } else if (chdir(pw->pw_dir) < 0) { 1039 if (chdir("/") < 0) { 1040 reply(530, "User %s: can't change directory to %s.", 1041 pw->pw_name, pw->pw_dir); 1042 goto bad; 1043 } else 1044 lreply(230, "No directory! Logging in with home=/"); 1045 } 1046 if (seteuid(pw->pw_uid) < 0) { 1047 reply(550, "Can't set uid."); 1048 goto bad; 1049 } 1050 sigprocmask(SIG_UNBLOCK, &allsigs, NULL); 1051 1052 /* 1053 * Set home directory so that use of ~ (tilde) works correctly. 1054 */ 1055 if (getcwd(homedir, MAXPATHLEN) != NULL) { 1056 if (setenv("HOME", homedir, 1) == -1) { 1057 reply(550, "Can't setup environment."); 1058 goto bad; 1059 } 1060 } 1061 1062 /* 1063 * Display a login message, if it exists. 1064 * N.B. reply(230,) must follow the message. 1065 */ 1066 motd = login_getcapstr(lc, "welcome", NULL, NULL); 1067 if ((fp = fopen(motd ? motd : _PATH_FTPLOGINMESG, "r")) != NULL) { 1068 char *cp, line[LINE_MAX]; 1069 1070 while (fgets(line, sizeof(line), fp) != NULL) { 1071 if ((cp = strchr(line, '\n')) != NULL) 1072 *cp = '\0'; 1073 lreply(230, "%s", line); 1074 } 1075 (void) fflush(stdout); 1076 (void) fclose(fp); 1077 } 1078 if (motd != NULL) 1079 free(motd); 1080 if (guest) { 1081 if (ident != NULL) 1082 free(ident); 1083 ident = strdup(passwd); 1084 if (ident == NULL) 1085 fatal("Ran out of memory."); 1086 reply(230, "Guest login ok, access restrictions apply."); 1087#ifdef HASSETPROCTITLE 1088 snprintf(proctitle, sizeof(proctitle), 1089 "%s: anonymous/%.*s", remotehost, 1090 (int)(sizeof(proctitle) - sizeof(remotehost) - 1091 sizeof(": anonymous/")), passwd); 1092 setproctitle("%s", proctitle); 1093#endif /* HASSETPROCTITLE */ 1094 if (logging) 1095 syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s", 1096 remotehost, passwd); 1097 } else { 1098 reply(230, "User %s logged in.", pw->pw_name); 1099#ifdef HASSETPROCTITLE 1100 snprintf(proctitle, sizeof(proctitle), 1101 "%s: %s", remotehost, pw->pw_name); 1102 setproctitle("%s", proctitle); 1103#endif /* HASSETPROCTITLE */ 1104 if (logging) 1105 syslog(LOG_INFO, "FTP LOGIN FROM %s as %s", 1106 remotehost, pw->pw_name); 1107 } 1108 login_close(lc); 1109 lc = NULL; 1110 return; 1111bad: 1112 /* Forget all about it... */ 1113 login_close(lc); 1114 lc = NULL; 1115 end_login(); 1116} 1117 1118void 1119retrieve(cmd, name) 1120 char *cmd, *name; 1121{ 1122 FILE *fin, *dout; 1123 struct stat st; 1124 int (*closefunc)(FILE *); 1125 time_t start; 1126 1127 if (cmd == 0) { 1128 fin = fopen(name, "r"), closefunc = fclose; 1129 st.st_size = 0; 1130 } else { 1131 char line[BUFSIZ]; 1132 1133 (void) snprintf(line, sizeof(line), cmd, name); 1134 name = line; 1135 fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose; 1136 st.st_size = -1; 1137 st.st_blksize = BUFSIZ; 1138 } 1139 if (fin == NULL) { 1140 if (errno != 0) { 1141 perror_reply(550, name); 1142 if (cmd == 0) { 1143 LOGCMD("get", name); 1144 } 1145 } 1146 return; 1147 } 1148 byte_count = -1; 1149 if (cmd == 0 && (fstat(fileno(fin), &st) < 0 || !S_ISREG(st.st_mode))) { 1150 reply(550, "%s: not a plain file.", name); 1151 goto done; 1152 } 1153 if (restart_point) { 1154 if (type == TYPE_A) { 1155 off_t i, n; 1156 int c; 1157 1158 n = restart_point; 1159 i = 0; 1160 while (i++ < n) { 1161 if ((c=getc(fin)) == EOF) { 1162 perror_reply(550, name); 1163 goto done; 1164 } 1165 if (c == '\n') 1166 i++; 1167 } 1168 } else if (lseek(fileno(fin), restart_point, SEEK_SET) < 0) { 1169 perror_reply(550, name); 1170 goto done; 1171 } 1172 } 1173 dout = dataconn(name, st.st_size, "w"); 1174 if (dout == NULL) 1175 goto done; 1176 time(&start); 1177 send_data(fin, dout, st.st_blksize, st.st_size, 1178 (restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode))); 1179 if ((cmd == 0) && stats) 1180 logxfer(name, byte_count, start); 1181 (void) fclose(dout); 1182 data = -1; 1183done: 1184 if (pdata >= 0) 1185 (void) close(pdata); 1186 pdata = -1; 1187 if (cmd == 0) 1188 LOGBYTES("get", name, byte_count); 1189 (*closefunc)(fin); 1190} 1191 1192void 1193store(name, mode, unique) 1194 char *name, *mode; 1195 int unique; 1196{ 1197 FILE *fout, *din; 1198 int (*closefunc)(FILE *); 1199 struct stat st; 1200 int fd; 1201 1202 if (restart_point && *mode != 'a') 1203 mode = "r+"; 1204 1205 if (unique && stat(name, &st) == 0) { 1206 char *nam; 1207 1208 fd = guniquefd(name, &nam); 1209 if (fd == -1) { 1210 LOGCMD(*mode == 'w' ? "put" : "append", name); 1211 return; 1212 } 1213 name = nam; 1214 fout = fdopen(fd, mode); 1215 } else 1216 fout = fopen(name, mode); 1217 1218 closefunc = fclose; 1219 if (fout == NULL) { 1220 perror_reply(553, name); 1221 LOGCMD(*mode == 'w' ? "put" : "append", name); 1222 return; 1223 } 1224 byte_count = -1; 1225 if (restart_point) { 1226 if (type == TYPE_A) { 1227 off_t i, n; 1228 int c; 1229 1230 n = restart_point; 1231 i = 0; 1232 while (i++ < n) { 1233 if ((c=getc(fout)) == EOF) { 1234 perror_reply(550, name); 1235 goto done; 1236 } 1237 if (c == '\n') 1238 i++; 1239 } 1240 /* 1241 * We must do this seek to "current" position 1242 * because we are changing from reading to 1243 * writing. 1244 */ 1245 if (fseek(fout, 0L, SEEK_CUR) < 0) { 1246 perror_reply(550, name); 1247 goto done; 1248 } 1249 } else if (lseek(fileno(fout), restart_point, SEEK_SET) < 0) { 1250 perror_reply(550, name); 1251 goto done; 1252 } 1253 } 1254 din = dataconn(name, (off_t)-1, "r"); 1255 if (din == NULL) 1256 goto done; 1257 if (receive_data(din, fout) == 0) { 1258 if (unique) 1259 reply(226, "Transfer complete (unique file name:%s).", 1260 name); 1261 else 1262 reply(226, "Transfer complete."); 1263 } 1264 (void) fclose(din); 1265 data = -1; 1266 pdata = -1; 1267done: 1268 LOGBYTES(*mode == 'w' ? "put" : "append", name, byte_count); 1269 (*closefunc)(fout); 1270} 1271 1272static FILE * 1273getdatasock(mode) 1274 char *mode; 1275{ 1276 int on = 1, s, t, tries; 1277 1278 if (data >= 0) 1279 return (fdopen(data, mode)); 1280 sigprocmask (SIG_BLOCK, &allsigs, NULL); 1281 s = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 1282 if (s < 0) 1283 goto bad; 1284 if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, 1285 (char *) &on, sizeof(on)) < 0) 1286 goto bad; 1287 /* anchor socket to avoid multi-homing problems */ 1288 data_source = ctrl_addr; 1289 data_source.su_port = htons(20); /* ftp-data port */ 1290 (void) seteuid(0); 1291 for (tries = 1; ; tries++) { 1292 if (bind(s, (struct sockaddr *)&data_source, 1293 data_source.su_len) >= 0) 1294 break; 1295 if (errno != EADDRINUSE || tries > 10) { 1296 (void) seteuid(pw->pw_uid); 1297 goto bad; 1298 } 1299 sleep(tries); 1300 } 1301 (void) seteuid((uid_t)pw->pw_uid); 1302 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1303 1304#ifdef IP_TOS 1305 if (ctrl_addr.su_family == AF_INET) { 1306 on = IPTOS_THROUGHPUT; 1307 if (setsockopt(s, IPPROTO_IP, IP_TOS, (char *)&on, 1308 sizeof(int)) < 0) 1309 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 1310 } 1311#endif 1312#ifdef TCP_NOPUSH 1313 /* 1314 * Turn off push flag to keep sender TCP from sending short packets 1315 * at the boundaries of each write(). Should probably do a SO_SNDBUF 1316 * to set the send buffer size as well, but that may not be desirable 1317 * in heavy-load situations. 1318 */ 1319 on = 1; 1320 if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, (char *)&on, sizeof(on)) < 0) 1321 syslog(LOG_WARNING, "setsockopt (TCP_NOPUSH): %m"); 1322#endif 1323#ifdef SO_SNDBUF 1324 on = 65536; 1325 if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, (char *)&on, sizeof(on)) < 0) 1326 syslog(LOG_WARNING, "setsockopt (SO_SNDBUF): %m"); 1327#endif 1328 1329 return (fdopen(s, mode)); 1330bad: 1331 /* Return the real value of errno (close may change it) */ 1332 t = errno; 1333 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1334 (void) close(s); 1335 errno = t; 1336 return (NULL); 1337} 1338 1339static FILE * 1340dataconn(name, size, mode) 1341 char *name; 1342 off_t size; 1343 char *mode; 1344{ 1345 char sizebuf[32]; 1346 FILE *file; 1347 int retry = 0; 1348 in_port_t *p; 1349 u_char *fa, *ha; 1350 int alen; 1351 1352 file_size = size; 1353 byte_count = 0; 1354 if (size != (off_t) -1) { 1355 (void) snprintf(sizebuf, sizeof(sizebuf), " (%qd bytes)", 1356 size); 1357 } else 1358 sizebuf[0] = '\0'; 1359 if (pdata >= 0) { 1360 union sockunion from; 1361 int s; 1362 socklen_t fromlen = sizeof(from); 1363 1364 (void) alarm ((unsigned) timeout); 1365 s = accept(pdata, (struct sockaddr *)&from, &fromlen); 1366 (void) alarm (0); 1367 if (s < 0) { 1368 reply(425, "Can't open data connection."); 1369 (void) close(pdata); 1370 pdata = -1; 1371 return (NULL); 1372 } 1373 switch (from.su_family) { 1374 case AF_INET: 1375 p = (in_port_t *)&from.su_sin.sin_port; 1376 fa = (u_char *)&from.su_sin.sin_addr; 1377 ha = (u_char *)&his_addr.su_sin.sin_addr; 1378 alen = sizeof(struct in_addr); 1379 break; 1380 case AF_INET6: 1381 p = (in_port_t *)&from.su_sin6.sin6_port; 1382 fa = (u_char *)&from.su_sin6.sin6_addr; 1383 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1384 alen = sizeof(struct in6_addr); 1385 break; 1386 default: 1387 perror_reply(425, "Can't build data connection"); 1388 (void) close(pdata); 1389 (void) close(s); 1390 pdata = -1; 1391 return (NULL); 1392 } 1393 if (from.su_family != his_addr.su_family || 1394 ntohs(*p) < IPPORT_RESERVED) { 1395 perror_reply(425, "Can't build data connection"); 1396 (void) close(pdata); 1397 (void) close(s); 1398 pdata = -1; 1399 return (NULL); 1400 } 1401 if (portcheck && memcmp(fa, ha, alen) != 0) { 1402 perror_reply(435, "Can't build data connection"); 1403 (void) close(pdata); 1404 (void) close(s); 1405 pdata = -1; 1406 return (NULL); 1407 } 1408 (void) close(pdata); 1409 pdata = s; 1410 reply(150, "Opening %s mode data connection for '%s'%s.", 1411 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1412 return (fdopen(pdata, mode)); 1413 } 1414 if (data >= 0) { 1415 reply(125, "Using existing data connection for '%s'%s.", 1416 name, sizebuf); 1417 usedefault = 1; 1418 return (fdopen(data, mode)); 1419 } 1420 if (usedefault) 1421 data_dest = his_addr; 1422 usedefault = 1; 1423 file = getdatasock(mode); 1424 if (file == NULL) { 1425 char hbuf[MAXHOSTNAMELEN], pbuf[10]; 1426 1427 getnameinfo((struct sockaddr *)&data_source, data_source.su_len, 1428 hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), 1429 NI_NUMERICHOST | NI_NUMERICSERV); 1430 reply(425, "Can't create data socket (%s,%s): %s.", 1431 hbuf, pbuf, strerror(errno)); 1432 return (NULL); 1433 } 1434 data = fileno(file); 1435 1436 /* 1437 * attempt to connect to reserved port on client machine; 1438 * this looks like an attack 1439 */ 1440 switch (data_dest.su_family) { 1441 case AF_INET: 1442 p = (in_port_t *)&data_dest.su_sin.sin_port; 1443 fa = (u_char *)&data_dest.su_sin.sin_addr; 1444 ha = (u_char *)&his_addr.su_sin.sin_addr; 1445 alen = sizeof(struct in_addr); 1446 break; 1447 case AF_INET6: 1448 p = (in_port_t *)&data_dest.su_sin6.sin6_port; 1449 fa = (u_char *)&data_dest.su_sin6.sin6_addr; 1450 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1451 alen = sizeof(struct in6_addr); 1452 break; 1453 default: 1454 perror_reply(425, "Can't build data connection"); 1455 (void) fclose(file); 1456 pdata = -1; 1457 return (NULL); 1458 } 1459 if (data_dest.su_family != his_addr.su_family || 1460 ntohs(*p) < IPPORT_RESERVED || ntohs(*p) == 2049) { /* XXX */ 1461 perror_reply(425, "Can't build data connection"); 1462 (void) fclose(file); 1463 data = -1; 1464 return NULL; 1465 } 1466 if (portcheck && memcmp(fa, ha, alen) != 0) { 1467 perror_reply(435, "Can't build data connection"); 1468 (void) fclose(file); 1469 data = -1; 1470 return NULL; 1471 } 1472 while (connect(data, (struct sockaddr *)&data_dest, 1473 data_dest.su_len) < 0) { 1474 if (errno == EADDRINUSE && retry < swaitmax) { 1475 sleep((unsigned) swaitint); 1476 retry += swaitint; 1477 continue; 1478 } 1479 perror_reply(425, "Can't build data connection"); 1480 (void) fclose(file); 1481 data = -1; 1482 return (NULL); 1483 } 1484 reply(150, "Opening %s mode data connection for '%s'%s.", 1485 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1486 return (file); 1487} 1488 1489/* 1490 * Tranfer the contents of "instr" to "outstr" peer using the appropriate 1491 * encapsulation of the data subject to Mode, Structure, and Type. 1492 * 1493 * NB: Form isn't handled. 1494 */ 1495static int 1496send_data(instr, outstr, blksize, filesize, isreg) 1497 FILE *instr, *outstr; 1498 off_t blksize; 1499 off_t filesize; 1500 int isreg; 1501{ 1502 int c, cnt, filefd, netfd; 1503 char *buf, *bp; 1504 size_t len; 1505 1506 transflag++; 1507 switch (type) { 1508 1509 case TYPE_A: 1510 while ((c = getc(instr)) != EOF) { 1511 if (recvurg) 1512 goto got_oob; 1513 byte_count++; 1514 if (c == '\n') { 1515 if (ferror(outstr)) 1516 goto data_err; 1517 (void) putc('\r', outstr); 1518 } 1519 (void) putc(c, outstr); 1520 } 1521 fflush(outstr); 1522 transflag = 0; 1523 if (ferror(instr)) 1524 goto file_err; 1525 if (ferror(outstr)) 1526 goto data_err; 1527 reply(226, "Transfer complete."); 1528 return(0); 1529 1530 case TYPE_I: 1531 case TYPE_L: 1532 /* 1533 * isreg is only set if we are not doing restart and we 1534 * are sending a regular file 1535 */ 1536 netfd = fileno(outstr); 1537 filefd = fileno(instr); 1538 1539 if (isreg && filesize < (off_t)16 * 1024 * 1024) { 1540 buf = mmap(0, filesize, PROT_READ, MAP_SHARED, filefd, 1541 (off_t)0); 1542 if (buf == MAP_FAILED) { 1543 syslog(LOG_WARNING, "mmap(%lu): %m", 1544 (unsigned long)filesize); 1545 goto oldway; 1546 } 1547 bp = buf; 1548 len = filesize; 1549 do { 1550 cnt = write(netfd, bp, len); 1551 if (recvurg) { 1552 munmap(buf, (size_t)filesize); 1553 goto got_oob; 1554 } 1555 len -= cnt; 1556 bp += cnt; 1557 if (cnt > 0) byte_count += cnt; 1558 } while(cnt > 0 && len > 0); 1559 1560 transflag = 0; 1561 munmap(buf, (size_t)filesize); 1562 if (cnt < 0) 1563 goto data_err; 1564 reply(226, "Transfer complete."); 1565 return(0); 1566 } 1567 1568oldway: 1569 if ((buf = malloc((u_int)blksize)) == NULL) { 1570 transflag = 0; 1571 perror_reply(451, "Local resource failure: malloc"); 1572 return(-1); 1573 } 1574 1575 while ((cnt = read(filefd, buf, (u_int)blksize)) > 0 && 1576 write(netfd, buf, cnt) == cnt) 1577 byte_count += cnt; 1578 transflag = 0; 1579 (void)free(buf); 1580 if (cnt != 0) { 1581 if (cnt < 0) 1582 goto file_err; 1583 goto data_err; 1584 } 1585 reply(226, "Transfer complete."); 1586 return(0); 1587 default: 1588 transflag = 0; 1589 reply(550, "Unimplemented TYPE %d in send_data", type); 1590 return(-1); 1591 } 1592 1593data_err: 1594 transflag = 0; 1595 perror_reply(426, "Data connection"); 1596 return(-1); 1597 1598file_err: 1599 transflag = 0; 1600 perror_reply(551, "Error on input file"); 1601 return(-1); 1602 1603got_oob: 1604 myoob(); 1605 recvurg = 0; 1606 transflag = 0; 1607 return(-1); 1608} 1609 1610/* 1611 * Transfer data from peer to "outstr" using the appropriate encapulation of 1612 * the data subject to Mode, Structure, and Type. 1613 * 1614 * N.B.: Form isn't handled. 1615 */ 1616static int 1617receive_data(instr, outstr) 1618 FILE *instr, *outstr; 1619{ 1620 int c; 1621 int cnt; 1622 char buf[BUFSIZ]; 1623 struct sigaction sa, sa_saved; 1624 volatile int bare_lfs = 0; 1625 1626 transflag++; 1627 switch (type) { 1628 1629 case TYPE_I: 1630 case TYPE_L: 1631 memset(&sa, 0, sizeof(sa)); 1632 sigfillset(&sa.sa_mask); 1633 sa.sa_flags = SA_RESTART; 1634 sa.sa_handler = lostconn; 1635 (void) sigaction(SIGALRM, &sa, &sa_saved); 1636 do { 1637 (void) alarm ((unsigned) timeout); 1638 cnt = read(fileno(instr), buf, sizeof(buf)); 1639 (void) alarm (0); 1640 if (recvurg) 1641 goto got_oob; 1642 1643 if (cnt > 0) { 1644 if (write(fileno(outstr), buf, cnt) != cnt) 1645 goto file_err; 1646 byte_count += cnt; 1647 } 1648 } while (cnt > 0); 1649 (void) sigaction(SIGALRM, &sa_saved, NULL); 1650 if (cnt < 0) 1651 goto data_err; 1652 transflag = 0; 1653 return (0); 1654 1655 case TYPE_E: 1656 reply(553, "TYPE E not implemented."); 1657 transflag = 0; 1658 return (-1); 1659 1660 case TYPE_A: 1661 while ((c = getc(instr)) != EOF) { 1662 if (recvurg) 1663 goto got_oob; 1664 byte_count++; 1665 if (c == '\n') 1666 bare_lfs++; 1667 while (c == '\r') { 1668 if (ferror(outstr)) 1669 goto data_err; 1670 if ((c = getc(instr)) != '\n') { 1671 (void) putc ('\r', outstr); 1672 if (c == '\0' || c == EOF) 1673 goto contin2; 1674 } 1675 } 1676 (void) putc(c, outstr); 1677 contin2: ; 1678 } 1679 fflush(outstr); 1680 if (ferror(instr)) 1681 goto data_err; 1682 if (ferror(outstr)) 1683 goto file_err; 1684 transflag = 0; 1685 if (bare_lfs) { 1686 lreply(226, 1687 "WARNING! %d bare linefeeds received in ASCII mode", 1688 bare_lfs); 1689 printf(" File may not have transferred correctly.\r\n"); 1690 } 1691 return (0); 1692 default: 1693 reply(550, "Unimplemented TYPE %d in receive_data", type); 1694 transflag = 0; 1695 return (-1); 1696 } 1697 1698data_err: 1699 transflag = 0; 1700 perror_reply(426, "Data Connection"); 1701 return (-1); 1702 1703file_err: 1704 transflag = 0; 1705 perror_reply(452, "Error writing file"); 1706 return (-1); 1707 1708got_oob: 1709 myoob(); 1710 recvurg = 0; 1711 transflag = 0; 1712 return (-1); 1713} 1714 1715void 1716statfilecmd(filename) 1717 char *filename; 1718{ 1719 FILE *fin; 1720 int c; 1721 int atstart; 1722 char line[LINE_MAX]; 1723 1724 (void)snprintf(line, sizeof(line), "/bin/ls -lgA %s", filename); 1725 fin = ftpd_popen(line, "r"); 1726 lreply(211, "status of %s:", filename); 1727 atstart = 1; 1728 while ((c = getc(fin)) != EOF) { 1729 if (c == '\n') { 1730 if (ferror(stdout)){ 1731 perror_reply(421, "control connection"); 1732 (void) ftpd_pclose(fin); 1733 dologout(1); 1734 /* NOTREACHED */ 1735 } 1736 if (ferror(fin)) { 1737 perror_reply(551, filename); 1738 (void) ftpd_pclose(fin); 1739 return; 1740 } 1741 (void) putc('\r', stdout); 1742 } 1743 if (atstart && isdigit(c)) 1744 (void) putc(' ', stdout); 1745 (void) putc(c, stdout); 1746 atstart = (c == '\n'); 1747 } 1748 (void) ftpd_pclose(fin); 1749 reply(211, "End of Status"); 1750} 1751 1752void 1753statcmd() 1754{ 1755 union sockunion *su; 1756 u_char *a, *p; 1757 char hbuf[MAXHOSTNAMELEN]; 1758 int ispassive; 1759 1760 lreply(211, "%s FTP server status:", hostname); 1761 printf(" %s\r\n", version); 1762 getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len, 1763 hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST); 1764 printf(" Connected to %s", remotehost); 1765 if (strcmp(remotehost, hbuf) != 0) 1766 printf(" (%s)", hbuf); 1767 printf("\r\n"); 1768 if (logged_in) { 1769 if (guest) 1770 printf(" Logged in anonymously\r\n"); 1771 else 1772 printf(" Logged in as %s\r\n", pw->pw_name); 1773 } else if (askpasswd) 1774 printf(" Waiting for password\r\n"); 1775 else 1776 printf(" Waiting for user name\r\n"); 1777 printf(" TYPE: %s", typenames[type]); 1778 if (type == TYPE_A || type == TYPE_E) 1779 printf(", FORM: %s", formnames[form]); 1780 if (type == TYPE_L) 1781#if NBBY == 8 1782 printf(" %d", NBBY); 1783#else 1784 printf(" %d", bytesize); /* need definition! */ 1785#endif 1786 printf("; STRUcture: %s; transfer MODE: %s\r\n", 1787 strunames[stru], modenames[mode]); 1788 ispassive = 0; 1789 if (data != -1) 1790 printf(" Data connection open\r\n"); 1791 else if (pdata != -1) { 1792 printf(" in Passive mode\r\n"); 1793 su = (union sockunion *)&pasv_addr; 1794 ispassive++; 1795 goto printaddr; 1796 } else if (usedefault == 0) { 1797 su = (union sockunion *)&data_dest; 1798printaddr: 1799 /* PASV/PORT */ 1800 if (su->su_family == AF_INET) { 1801 if (ispassive) 1802 printf("211- PASV "); 1803 else 1804 printf("211- PORT "); 1805 a = (u_char *) &su->su_sin.sin_addr; 1806 p = (u_char *) &su->su_sin.sin_port; 1807 printf("(%u,%u,%u,%u,%u,%u)\r\n", 1808 a[0], a[1], a[2], a[3], 1809 p[0], p[1]); 1810 } 1811 1812 /* LPSV/LPRT */ 1813 { 1814 int alen, af, i; 1815 1816 alen = 0; 1817 switch (su->su_family) { 1818 case AF_INET: 1819 a = (u_char *) &su->su_sin.sin_addr; 1820 p = (u_char *) &su->su_sin.sin_port; 1821 alen = sizeof(su->su_sin.sin_addr); 1822 af = 4; 1823 break; 1824 case AF_INET6: 1825 a = (u_char *) &su->su_sin6.sin6_addr; 1826 p = (u_char *) &su->su_sin6.sin6_port; 1827 alen = sizeof(su->su_sin6.sin6_addr); 1828 af = 6; 1829 break; 1830 default: 1831 af = 0; 1832 break; 1833 } 1834 if (af) { 1835 if (ispassive) 1836 printf("211- LPSV "); 1837 else 1838 printf("211- LPRT "); 1839 printf("(%u,%u", af, alen); 1840 for (i = 0; i < alen; i++) 1841 printf(",%u", a[i]); 1842 printf(",%u,%u,%u)\r\n", 2, p[0], p[1]); 1843 } 1844 } 1845 1846 /* EPRT/EPSV */ 1847 { 1848 u_char af; 1849 1850 switch (su->su_family) { 1851 case AF_INET: 1852 af = 1; 1853 break; 1854 case AF_INET6: 1855 af = 2; 1856 break; 1857 default: 1858 af = 0; 1859 break; 1860 } 1861 if (af) { 1862 char hbuf[MAXHOSTNAMELEN], pbuf[10]; 1863 union sockunion tmp = *su; 1864 1865 if (tmp.su_family == AF_INET6) 1866 tmp.su_sin6.sin6_scope_id = 0; 1867 if (getnameinfo((struct sockaddr *)&tmp, tmp.su_len, 1868 hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), 1869 NI_NUMERICHOST | NI_NUMERICSERV) == 0) { 1870 if (ispassive) 1871 printf("211- EPSV "); 1872 else 1873 printf("211- EPRT "); 1874 printf("(|%u|%s|%s|)\r\n", 1875 af, hbuf, pbuf); 1876 } 1877 } 1878 } 1879 } else 1880 printf(" No data connection\r\n"); 1881 reply(211, "End of status"); 1882} 1883 1884void 1885fatal(s) 1886 char *s; 1887{ 1888 1889 reply(451, "Error in server: %s", s); 1890 reply(221, "Closing connection due to server error."); 1891 dologout(0); 1892 /* NOTREACHED */ 1893} 1894 1895void 1896reply(int n, const char *fmt, ...) 1897{ 1898 char *buf, *p, *next; 1899 int rval; 1900 va_list ap; 1901 1902 va_start(ap, fmt); 1903 rval = vasprintf(&buf, fmt, ap); 1904 va_end(ap); 1905 if (rval == -1 || buf == NULL) { 1906 printf("412 Local resource failure: malloc\r\n"); 1907 fflush(stdout); 1908 dologout(1); 1909 } 1910 next = buf; 1911 while ((p = strsep(&next, "\n\r"))) { 1912 printf("%d%s %s\r\n", n, (next != '\0') ? "-" : "", p); 1913 if (debug) 1914 syslog(LOG_DEBUG, "<--- %d%s %s", n, 1915 (next != '\0') ? "-" : "", p); 1916 } 1917 (void)fflush(stdout); 1918 free(buf); 1919} 1920 1921void 1922lreply(int n, const char *fmt, ...) 1923{ 1924 va_list ap; 1925 1926 va_start(ap, fmt); 1927 (void)printf("%d- ", n); 1928 (void)vprintf(fmt, ap); 1929 va_end(ap); 1930 (void)printf("\r\n"); 1931 (void)fflush(stdout); 1932 if (debug) { 1933 va_start(ap, fmt); 1934 syslog(LOG_DEBUG, "<--- %d- ", n); 1935 vsyslog(LOG_DEBUG, fmt, ap); 1936 va_end(ap); 1937 } 1938} 1939 1940static void 1941ack(s) 1942 char *s; 1943{ 1944 1945 reply(250, "%s command successful.", s); 1946} 1947 1948void 1949nack(s) 1950 char *s; 1951{ 1952 1953 reply(502, "%s command not implemented.", s); 1954} 1955 1956/* ARGSUSED */ 1957void 1958yyerror(s) 1959 char *s; 1960{ 1961 char *cp; 1962 1963 if ((cp = strchr(cbuf,'\n'))) 1964 *cp = '\0'; 1965 reply(500, "'%s': command not understood.", cbuf); 1966} 1967 1968void 1969delete(name) 1970 char *name; 1971{ 1972 struct stat st; 1973 1974 LOGCMD("delete", name); 1975 if (stat(name, &st) < 0) { 1976 perror_reply(550, name); 1977 return; 1978 } 1979 if ((st.st_mode&S_IFMT) == S_IFDIR) { 1980 if (rmdir(name) < 0) { 1981 perror_reply(550, name); 1982 return; 1983 } 1984 goto done; 1985 } 1986 if (unlink(name) < 0) { 1987 perror_reply(550, name); 1988 return; 1989 } 1990done: 1991 ack("DELE"); 1992} 1993 1994void 1995cwd(path) 1996 char *path; 1997{ 1998 FILE *message; 1999 2000 if (chdir(path) < 0) 2001 perror_reply(550, path); 2002 else { 2003 if ((message = fopen(_PATH_CWDMESG, "r")) != NULL) { 2004 char *cp, line[LINE_MAX]; 2005 2006 while (fgets(line, sizeof(line), message) != NULL) { 2007 if ((cp = strchr(line, '\n')) != NULL) 2008 *cp = '\0'; 2009 lreply(250, "%s", line); 2010 } 2011 (void) fflush(stdout); 2012 (void) fclose(message); 2013 } 2014 ack("CWD"); 2015 } 2016} 2017 2018void 2019replydirname(name, message) 2020 const char *name, *message; 2021{ 2022 char *p, *ep; 2023 char npath[MAXPATHLEN * 2]; 2024 2025 p = npath; 2026 ep = &npath[sizeof(npath) - 1]; 2027 while (*name) { 2028 if (*name == '"') { 2029 if (ep - p < 2) 2030 break; 2031 *p++ = *name++; 2032 *p++ = '"'; 2033 } else { 2034 if (ep - p < 1) 2035 break; 2036 *p++ = *name++; 2037 } 2038 } 2039 *p = '\0'; 2040 reply(257, "\"%s\" %s", npath, message); 2041} 2042 2043void 2044makedir(name) 2045 char *name; 2046{ 2047 2048 LOGCMD("mkdir", name); 2049 if (mkdir(name, 0777) < 0) 2050 perror_reply(550, name); 2051 else 2052 replydirname(name, "directory created."); 2053} 2054 2055void 2056removedir(name) 2057 char *name; 2058{ 2059 2060 LOGCMD("rmdir", name); 2061 if (rmdir(name) < 0) 2062 perror_reply(550, name); 2063 else 2064 ack("RMD"); 2065} 2066 2067void 2068pwd() 2069{ 2070 char path[MAXPATHLEN]; 2071 2072 if (getcwd(path, sizeof(path)) == NULL) 2073 reply(550, "Can't get current directory: %s.", strerror(errno)); 2074 else 2075 replydirname(path, "is current directory."); 2076} 2077 2078char * 2079renamefrom(name) 2080 char *name; 2081{ 2082 struct stat st; 2083 2084 if (stat(name, &st) < 0) { 2085 perror_reply(550, name); 2086 return ((char *)0); 2087 } 2088 reply(350, "File exists, ready for destination name"); 2089 return (name); 2090} 2091 2092void 2093renamecmd(from, to) 2094 char *from, *to; 2095{ 2096 2097 LOGCMD2("rename", from, to); 2098 if (rename(from, to) < 0) 2099 perror_reply(550, "rename"); 2100 else 2101 ack("RNTO"); 2102} 2103 2104static void 2105dolog(sa) 2106 struct sockaddr *sa; 2107{ 2108 char hbuf[sizeof(remotehost)]; 2109 2110 getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), NULL, 0, 0); 2111 (void) strlcpy(remotehost, hbuf, sizeof(remotehost)); 2112 2113#ifdef HASSETPROCTITLE 2114 snprintf(proctitle, sizeof(proctitle), "%s: connected", remotehost); 2115 setproctitle("%s", proctitle); 2116#endif /* HASSETPROCTITLE */ 2117 2118 if (logging) 2119 syslog(LOG_INFO, "connection from %s", remotehost); 2120} 2121 2122/* 2123 * Record logout in wtmp file and exit with supplied status. 2124 * NOTE: because this is called from signal handlers it cannot 2125 * use stdio (or call other functions that use stdio). 2126 */ 2127void 2128dologout(status) 2129 int status; 2130{ 2131 2132 transflag = 0; 2133 2134 if (logged_in) { 2135 sigprocmask(SIG_BLOCK, &allsigs, NULL); 2136 ftpdlogwtmp(ttyline, "", ""); 2137 if (doutmp) 2138 logout(utmp.ut_line); 2139 } 2140 /* beware of flushing buffers after a SIGPIPE */ 2141 _exit(status); 2142} 2143 2144static void 2145sigurg(signo) 2146 int signo; 2147{ 2148 2149 recvurg = 1; 2150} 2151 2152static void 2153myoob() 2154{ 2155 char *cp; 2156 2157 /* only process if transfer occurring */ 2158 if (!transflag) 2159 return; 2160 cp = tmpline; 2161 if (getline(cp, 7, stdin) == NULL) { 2162 reply(221, "You could at least say goodbye."); 2163 dologout(0); 2164 } 2165 upper(cp); 2166 if (strcmp(cp, "ABOR\r\n") == 0) { 2167 tmpline[0] = '\0'; 2168 reply(426, "Transfer aborted. Data connection closed."); 2169 reply(226, "Abort successful"); 2170 } 2171 if (strcmp(cp, "STAT\r\n") == 0) { 2172 tmpline[0] = '\0'; 2173 if (file_size != (off_t) -1) 2174 reply(213, "Status: %qd of %qd bytes transferred", 2175 byte_count, file_size); 2176 else 2177 reply(213, "Status: %qd bytes transferred", byte_count); 2178 } 2179} 2180 2181/* 2182 * Note: a response of 425 is not mentioned as a possible response to 2183 * the PASV command in RFC959. However, it has been blessed as 2184 * a legitimate response by Jon Postel in a telephone conversation 2185 * with Rick Adams on 25 Jan 89. 2186 */ 2187void 2188passive() 2189{ 2190 socklen_t len; 2191 int on; 2192 u_char *p, *a; 2193 2194 if (pw == NULL) { 2195 reply(530, "Please login with USER and PASS"); 2196 return; 2197 } 2198 if (pdata >= 0) 2199 close(pdata); 2200 /* 2201 * XXX 2202 * At this point, it would be nice to have an algorithm that 2203 * inserted a growing delay in an attack scenario. Such a thing 2204 * would look like continual passive sockets being opened, but 2205 * nothing serious being done with them. They're not used to 2206 * move data; the entire attempt is just to use tcp FIN_WAIT 2207 * resources. 2208 */ 2209 pdata = socket(AF_INET, SOCK_STREAM, 0); 2210 if (pdata < 0) { 2211 perror_reply(425, "Can't open passive connection"); 2212 return; 2213 } 2214 2215 on = IP_PORTRANGE_HIGH; 2216 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2217 (char *)&on, sizeof(on)) < 0) 2218 goto pasv_error; 2219 2220 pasv_addr = ctrl_addr; 2221 pasv_addr.su_sin.sin_port = 0; 2222 if (bind(pdata, (struct sockaddr *)&pasv_addr, 2223 pasv_addr.su_len) < 0) 2224 goto pasv_error; 2225 2226 len = sizeof(pasv_addr); 2227 if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0) 2228 goto pasv_error; 2229 if (listen(pdata, 1) < 0) 2230 goto pasv_error; 2231 a = (u_char *) &pasv_addr.su_sin.sin_addr; 2232 p = (u_char *) &pasv_addr.su_sin.sin_port; 2233 2234 reply(227, "Entering Passive Mode (%u,%u,%u,%u,%u,%u)", a[0], 2235 a[1], a[2], a[3], p[0], p[1]); 2236 return; 2237 2238pasv_error: 2239 (void) close(pdata); 2240 pdata = -1; 2241 perror_reply(425, "Can't open passive connection"); 2242 return; 2243} 2244 2245/* 2246 * convert protocol identifier to/from AF 2247 */ 2248int 2249lpsvproto2af(int proto) 2250{ 2251 2252 switch (proto) { 2253 case 4: return AF_INET; 2254#ifdef INET6 2255 case 6: return AF_INET6; 2256#endif 2257 default: return -1; 2258 } 2259} 2260 2261int 2262af2lpsvproto(int af) 2263{ 2264 2265 switch (af) { 2266 case AF_INET: return 4; 2267#ifdef INET6 2268 case AF_INET6: return 6; 2269#endif 2270 default: return -1; 2271 } 2272} 2273 2274int 2275epsvproto2af(int proto) 2276{ 2277 2278 switch (proto) { 2279 case 1: return AF_INET; 2280#ifdef INET6 2281 case 2: return AF_INET6; 2282#endif 2283 default: return -1; 2284 } 2285} 2286 2287int 2288af2epsvproto(int af) 2289{ 2290 2291 switch (af) { 2292 case AF_INET: return 1; 2293#ifdef INET6 2294 case AF_INET6: return 2; 2295#endif 2296 default: return -1; 2297 } 2298} 2299 2300/* 2301 * 228 Entering Long Passive Mode (af, hal, h1, h2, h3,..., pal, p1, p2...) 2302 * 229 Entering Extended Passive Mode (|||port|) 2303 */ 2304void 2305long_passive(char *cmd, int pf) 2306{ 2307 socklen_t len; 2308 int on; 2309 u_char *p, *a; 2310 2311 if (!logged_in) { 2312 syslog(LOG_NOTICE, "long passive but not logged in"); 2313 reply(503, "Login with USER first."); 2314 return; 2315 } 2316 2317 if (pf != PF_UNSPEC && ctrl_addr.su_family != pf) { 2318 /* 2319 * XXX 2320 * only EPRT/EPSV ready clients will understand this 2321 */ 2322 if (strcmp(cmd, "EPSV") != 0) 2323 reply(501, "Network protocol mismatch"); /*XXX*/ 2324 else 2325 epsv_protounsupp("Network protocol mismatch"); 2326 2327 return; 2328 } 2329 2330 if (pdata >= 0) 2331 close(pdata); 2332 /* 2333 * XXX 2334 * At this point, it would be nice to have an algorithm that 2335 * inserted a growing delay in an attack scenario. Such a thing 2336 * would look like continual passive sockets being opened, but 2337 * nothing serious being done with them. They not used to move 2338 * data; the entire attempt is just to use tcp FIN_WAIT 2339 * resources. 2340 */ 2341 pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 2342 if (pdata < 0) { 2343 perror_reply(425, "Can't open passive connection"); 2344 return; 2345 } 2346 2347 switch (ctrl_addr.su_family) { 2348 case AF_INET: 2349 on = IP_PORTRANGE_HIGH; 2350 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2351 (char *)&on, sizeof(on)) < 0) 2352 goto pasv_error; 2353 break; 2354 case AF_INET6: 2355 on = IPV6_PORTRANGE_HIGH; 2356 if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE, 2357 (char *)&on, sizeof(on)) < 0) 2358 goto pasv_error; 2359 break; 2360 } 2361 2362 pasv_addr = ctrl_addr; 2363 pasv_addr.su_port = 0; 2364 if (bind(pdata, (struct sockaddr *) &pasv_addr, pasv_addr.su_len) < 0) 2365 goto pasv_error; 2366 len = pasv_addr.su_len; 2367 if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0) 2368 goto pasv_error; 2369 if (listen(pdata, 1) < 0) 2370 goto pasv_error; 2371 p = (u_char *) &pasv_addr.su_port; 2372 2373 if (strcmp(cmd, "LPSV") == 0) { 2374 switch (pasv_addr.su_family) { 2375 case AF_INET: 2376 a = (u_char *) &pasv_addr.su_sin.sin_addr; 2377 reply(228, 2378 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2379 4, 4, a[0], a[1], a[2], a[3], 2, p[0], p[1]); 2380 return; 2381 case AF_INET6: 2382 a = (u_char *) &pasv_addr.su_sin6.sin6_addr; 2383 reply(228, 2384 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u," 2385 "%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2386 6, 16, a[0], a[1], a[2], a[3], a[4], 2387 a[5], a[6], a[7], a[8], a[9], a[10], 2388 a[11], a[12], a[13], a[14], a[15], 2389 2, p[0], p[1]); 2390 return; 2391 } 2392 } else if (strcmp(cmd, "EPSV") == 0) { 2393 switch (pasv_addr.su_family) { 2394 case AF_INET: 2395 case AF_INET6: 2396 reply(229, "Entering Extended Passive Mode (|||%u|)", 2397 ntohs(pasv_addr.su_port)); 2398 return; 2399 } 2400 } else { 2401 /* more proper error code? */ 2402 } 2403 2404 pasv_error: 2405 (void) close(pdata); 2406 pdata = -1; 2407 perror_reply(425, "Can't open passive connection"); 2408 return; 2409} 2410 2411/* 2412 * EPRT |proto|addr|port| 2413 */ 2414int 2415extended_port(const char *arg) 2416{ 2417 char *tmp = NULL; 2418 char *result[3]; 2419 char *p, *q; 2420 char delim; 2421 struct addrinfo hints; 2422 struct addrinfo *res = NULL; 2423 int i; 2424 unsigned long proto; 2425 2426 if (epsvall) { 2427 reply(501, "EPRT disallowed after EPSV ALL"); 2428 return -1; 2429 } 2430 2431 usedefault = 0; 2432 if (pdata >= 0) { 2433 (void) close(pdata); 2434 pdata = -1; 2435 } 2436 2437 tmp = strdup(arg); 2438 if (!tmp) { 2439 fatal("not enough core."); 2440 /*NOTREACHED*/ 2441 } 2442 p = tmp; 2443 delim = p[0]; 2444 p++; 2445 memset(result, 0, sizeof(result)); 2446 for (i = 0; i < 3; i++) { 2447 q = strchr(p, delim); 2448 if (!q || *q != delim) 2449 goto parsefail; 2450 *q++ = '\0'; 2451 result[i] = p; 2452 p = q; 2453 } 2454 2455 /* some more sanity check */ 2456 p = NULL; 2457 (void)strtoul(result[2], &p, 10); 2458 if (!*result[2] || *p) 2459 goto protounsupp; 2460 p = NULL; 2461 proto = strtoul(result[0], &p, 10); 2462 if (!*result[0] || *p) 2463 goto protounsupp; 2464 2465 memset(&hints, 0, sizeof(hints)); 2466 hints.ai_family = epsvproto2af((int)proto); 2467 if (hints.ai_family < 0) 2468 goto protounsupp; 2469 hints.ai_socktype = SOCK_STREAM; 2470 hints.ai_flags = AI_NUMERICHOST; /*no DNS*/ 2471 if (getaddrinfo(result[1], result[2], &hints, &res)) 2472 goto parsefail; 2473 if (res->ai_next) 2474 goto parsefail; 2475 if (sizeof(data_dest) < res->ai_addrlen) 2476 goto parsefail; 2477 memcpy(&data_dest, res->ai_addr, res->ai_addrlen); 2478 if (his_addr.su_family == AF_INET6 && 2479 data_dest.su_family == AF_INET6) { 2480 /* XXX more sanity checks! */ 2481 data_dest.su_sin6.sin6_scope_id = 2482 his_addr.su_sin6.sin6_scope_id; 2483 } 2484 if (pdata >= 0) { 2485 (void) close(pdata); 2486 pdata = -1; 2487 } 2488 reply(200, "EPRT command successful."); 2489 2490 if (tmp) 2491 free(tmp); 2492 if (res) 2493 freeaddrinfo(res); 2494 return 0; 2495 2496parsefail: 2497 reply(500, "Invalid argument, rejected."); 2498 usedefault = 1; 2499 if (tmp) 2500 free(tmp); 2501 if (res) 2502 freeaddrinfo(res); 2503 return -1; 2504 2505protounsupp: 2506 epsv_protounsupp("Protocol not supported"); 2507 usedefault = 1; 2508 if (tmp) 2509 free(tmp); 2510 if (res) 2511 freeaddrinfo(res); 2512 return -1; 2513} 2514 2515/* 2516 * 522 Protocol not supported (proto,...) 2517 * as we assume address family for control and data connections are the same, 2518 * we do not return the list of address families we support - instead, we 2519 * return the address family of the control connection. 2520 */ 2521void 2522epsv_protounsupp(const char *message) 2523{ 2524 int proto; 2525 2526 proto = af2epsvproto(ctrl_addr.su_family); 2527 if (proto < 0) 2528 reply(501, "%s", message); /*XXX*/ 2529 else 2530 reply(522, "%s, use (%d)", message, proto); 2531} 2532 2533/* 2534 * Generate unique name for file with basename "local". 2535 * The file named "local" is already known to exist. 2536 * Generates failure reply on error. 2537 */ 2538static int 2539guniquefd(local, nam) 2540 char *local; 2541 char **nam; 2542{ 2543 static char new[MAXPATHLEN]; 2544 struct stat st; 2545 int count, len, fd; 2546 char *cp; 2547 2548 cp = strrchr(local, '/'); 2549 if (cp) 2550 *cp = '\0'; 2551 if (stat(cp ? local : ".", &st) < 0) { 2552 perror_reply(553, cp ? local : "."); 2553 return (-1); 2554 } 2555 if (cp) 2556 *cp = '/'; 2557 len = strlcpy(new, local, sizeof(new)); 2558 if (len+2+1 >= sizeof(new)-1) 2559 return (-1); 2560 cp = new + len; 2561 *cp++ = '.'; 2562 for (count = 1; count < 100; count++) { 2563 (void)snprintf(cp, sizeof(new) - (cp - new), "%d", count); 2564 fd = open(new, O_RDWR|O_CREAT|O_EXCL, 0666); 2565 if (fd == -1) 2566 continue; 2567 if (nam) 2568 *nam = new; 2569 return (fd); 2570 } 2571 reply(452, "Unique file name cannot be created."); 2572 return (-1); 2573} 2574 2575/* 2576 * Format and send reply containing system error number. 2577 */ 2578void 2579perror_reply(code, string) 2580 int code; 2581 char *string; 2582{ 2583 2584 reply(code, "%s: %s.", string, strerror(errno)); 2585} 2586 2587static char *onefile[] = { 2588 "", 2589 0 2590}; 2591 2592void 2593send_file_list(whichf) 2594 char *whichf; 2595{ 2596 struct stat st; 2597 DIR *dirp = NULL; 2598 struct dirent *dir; 2599 FILE *dout = NULL; 2600 char **dirlist; 2601 char *dirname; 2602 int simple = 0; 2603 volatile int freeglob = 0; 2604 glob_t gl; 2605 2606 if (strpbrk(whichf, "~{[*?") != NULL) { 2607 memset(&gl, 0, sizeof(gl)); 2608 freeglob = 1; 2609 if (glob(whichf, 2610 GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE|GLOB_LIMIT, 2611 0, &gl)) { 2612 reply(550, "not found"); 2613 goto out; 2614 } else if (gl.gl_pathc == 0) { 2615 errno = ENOENT; 2616 perror_reply(550, whichf); 2617 goto out; 2618 } 2619 dirlist = gl.gl_pathv; 2620 } else { 2621 onefile[0] = whichf; 2622 dirlist = onefile; 2623 simple = 1; 2624 } 2625 2626 while ((dirname = *dirlist++)) { 2627 if (stat(dirname, &st) < 0) { 2628 /* 2629 * If user typed "ls -l", etc, and the client 2630 * used NLST, do what the user meant. 2631 */ 2632 if (dirname[0] == '-' && *dirlist == NULL && 2633 transflag == 0) { 2634 retrieve("/bin/ls %s", dirname); 2635 goto out; 2636 } 2637 perror_reply(550, whichf); 2638 if (dout != NULL) { 2639 (void) fclose(dout); 2640 transflag = 0; 2641 data = -1; 2642 pdata = -1; 2643 } 2644 goto out; 2645 } 2646 2647 if (S_ISREG(st.st_mode)) { 2648 if (dout == NULL) { 2649 dout = dataconn("file list", (off_t)-1, "w"); 2650 if (dout == NULL) 2651 goto out; 2652 transflag++; 2653 } 2654 fprintf(dout, "%s%s\n", dirname, 2655 type == TYPE_A ? "\r" : ""); 2656 byte_count += strlen(dirname) + 1; 2657 continue; 2658 } else if (!S_ISDIR(st.st_mode)) 2659 continue; 2660 2661 if ((dirp = opendir(dirname)) == NULL) 2662 continue; 2663 2664 while ((dir = readdir(dirp)) != NULL) { 2665 char nbuf[MAXPATHLEN]; 2666 2667 if (recvurg) { 2668 myoob(); 2669 recvurg = 0; 2670 transflag = 0; 2671 goto out; 2672 } 2673 2674 if (dir->d_name[0] == '.' && dir->d_namlen == 1) 2675 continue; 2676 if (dir->d_name[0] == '.' && dir->d_name[1] == '.' && 2677 dir->d_namlen == 2) 2678 continue; 2679 2680 snprintf(nbuf, sizeof(nbuf), "%s/%s", dirname, 2681 dir->d_name); 2682 2683 /* 2684 * We have to do a stat to insure it's 2685 * not a directory or special file. 2686 */ 2687 if (simple || (stat(nbuf, &st) == 0 && 2688 S_ISREG(st.st_mode))) { 2689 if (dout == NULL) { 2690 dout = dataconn("file list", (off_t)-1, 2691 "w"); 2692 if (dout == NULL) 2693 goto out; 2694 transflag++; 2695 } 2696 if (nbuf[0] == '.' && nbuf[1] == '/') 2697 fprintf(dout, "%s%s\n", &nbuf[2], 2698 type == TYPE_A ? "\r" : ""); 2699 else 2700 fprintf(dout, "%s%s\n", nbuf, 2701 type == TYPE_A ? "\r" : ""); 2702 byte_count += strlen(nbuf) + 1; 2703 } 2704 } 2705 (void) closedir(dirp); 2706 } 2707 2708 if (dout == NULL) 2709 reply(550, "No files found."); 2710 else if (ferror(dout) != 0) 2711 perror_reply(550, "Data connection"); 2712 else 2713 reply(226, "Transfer complete."); 2714 2715 transflag = 0; 2716 if (dout != NULL) 2717 (void) fclose(dout); 2718 else { 2719 if (pdata >= 0) 2720 close(pdata); 2721 } 2722 data = -1; 2723 pdata = -1; 2724out: 2725 if (freeglob) { 2726 freeglob = 0; 2727 globfree(&gl); 2728 } 2729} 2730 2731static void 2732reapchild(signo) 2733 int signo; 2734{ 2735 int save_errno = errno; 2736 int rval; 2737 2738 do { 2739 rval = waitpid(-1, NULL, WNOHANG); 2740 } while (rval > 0 || (rval == -1 && errno == EINTR)); 2741 errno = save_errno; 2742} 2743 2744void 2745logxfer(name, size, start) 2746 char *name; 2747 off_t size; 2748 time_t start; 2749{ 2750 char buf[400 + MAXHOSTNAMELEN*4 + MAXPATHLEN*4]; 2751 char dir[MAXPATHLEN], path[MAXPATHLEN], rpath[MAXPATHLEN]; 2752 char vremotehost[MAXHOSTNAMELEN*4], vpath[MAXPATHLEN*4]; 2753 char *vpw; 2754 time_t now; 2755 int len; 2756 2757 if ((statfd >= 0) && (getcwd(dir, sizeof(dir)) != NULL)) { 2758 time(&now); 2759 2760 vpw = malloc(strlen(guest ? guestpw : pw->pw_name) * 4 + 1); 2761 if (vpw == NULL) 2762 return; 2763 2764 snprintf(path, sizeof(path), "%s/%s", dir, name); 2765 if (realpath(path, rpath) == NULL) 2766 strlcpy(rpath, path, sizeof(rpath)); 2767 strvis(vpath, rpath, VIS_SAFE|VIS_NOSLASH); 2768 2769 strvis(vremotehost, remotehost, VIS_SAFE|VIS_NOSLASH); 2770 strvis(vpw, guest? guestpw : pw->pw_name, VIS_SAFE|VIS_NOSLASH); 2771 2772 if ((len = snprintf(buf, sizeof(buf), 2773 "%.24s %d %s %qd %s %c %s %c %c %s ftp %d %s %s\n", 2774 ctime(&now), now - start + (now == start), 2775 vremotehost, (long long)size, vpath, 2776 ((type == TYPE_A) ? 'a' : 'b'), "*" /* none yet */, 2777 'o', ((guest) ? 'a' : 'r'), 2778 vpw, 0 /* none yet */, 2779 ((guest) ? "*" : pw->pw_name), dhostname)) >= sizeof(buf) 2780 || len < 0) { 2781 if ((len = strlen(buf)) == 0) 2782 return; /* should not happen */ 2783 buf[len - 1] = '\n'; 2784 } 2785 write(statfd, buf, len); 2786 free(vpw); 2787 } 2788} 2789 2790#if defined(TCPWRAPPERS) 2791static int 2792check_host(sa) 2793 struct sockaddr *sa; 2794{ 2795 struct sockaddr_in *sin; 2796 struct hostent *hp; 2797 char *addr; 2798 2799 if (sa->sa_family != AF_INET) 2800 return 1; /*XXX*/ 2801 2802 sin = (struct sockaddr_in *)sa; 2803 hp = gethostbyaddr((char *)&sin->sin_addr, 2804 sizeof(struct in_addr), AF_INET); 2805 addr = inet_ntoa(sin->sin_addr); 2806 if (hp) { 2807 if (!hosts_ctl("ftpd", hp->h_name, addr, STRING_UNKNOWN)) { 2808 syslog(LOG_NOTICE, "tcpwrappers rejected: %s [%s]", 2809 hp->h_name, addr); 2810 return (0); 2811 } 2812 } else { 2813 if (!hosts_ctl("ftpd", STRING_UNKNOWN, addr, STRING_UNKNOWN)) { 2814 syslog(LOG_NOTICE, "tcpwrappers rejected: [%s]", addr); 2815 return (0); 2816 } 2817 } 2818 return (1); 2819} 2820#endif /* TCPWRAPPERS */ 2821 2822/* 2823 * Allocate space and return a copy of the specified dir. 2824 * If 'dir' begins with a tilde (~), expand it. 2825 */ 2826char * 2827copy_dir(dir, pw) 2828 char *dir; 2829 struct passwd *pw; 2830{ 2831 char *cp; 2832 char *newdir; 2833 char *user = NULL; 2834 size_t dirsiz; 2835 2836 /* Nothing to expand */ 2837 if (dir[0] != '~') 2838 return (strdup(dir)); 2839 2840 /* "dir" is of form ~user/some/dir, lookup user. */ 2841 if (dir[1] != '/' && dir[1] != '\0') { 2842 if ((cp = strchr(dir + 1, '/')) == NULL) 2843 cp = dir + strlen(dir); 2844 if ((user = malloc(cp - dir)) == NULL) 2845 return (NULL); 2846 strlcpy(user, dir + 1, cp - dir); 2847 2848 /* Only do lookup if it is a different user. */ 2849 if (strcmp(user, pw->pw_name) != 0) { 2850 if ((pw = getpwnam(user)) == NULL) { 2851 /* No such user, interpret literally */ 2852 free(user); 2853 return(strdup(dir)); 2854 } 2855 } 2856 } 2857 2858 /* 2859 * If there is no directory separator (/) then it is just pw_dir. 2860 * Otherwise, replace ~foo with pw_dir. 2861 */ 2862 if ((cp = strchr(dir + 1, '/')) == NULL) { 2863 newdir = strdup(pw->pw_dir); 2864 } else { 2865 dirsiz = strlen(cp) + strlen(pw->pw_dir) + 1; 2866 if ((newdir = malloc(dirsiz)) == NULL) { 2867 free(user); 2868 return (NULL); 2869 } 2870 strlcpy(newdir, pw->pw_dir, dirsiz); 2871 strlcat(newdir, cp, dirsiz); 2872 } 2873 2874 if (user) 2875 free(user); 2876 return(newdir); 2877} 2878