ftpd.c revision 1.191
1/* $OpenBSD: ftpd.c,v 1.191 2010/08/01 16:53:57 tobias Exp $ */ 2/* $NetBSD: ftpd.c,v 1.15 1995/06/03 22:46:47 mycroft Exp $ */ 3 4/* 5 * Copyright (C) 1997 and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33/* 34 * Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. Neither the name of the University nor the names of its contributors 46 * may be used to endorse or promote products derived from this software 47 * without specific prior written permission. 48 * 49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 59 * SUCH DAMAGE. 60 */ 61 62/* 63 * FTP server. 64 */ 65#include <sys/param.h> 66#include <sys/stat.h> 67#include <sys/ioctl.h> 68#include <sys/socket.h> 69#include <sys/wait.h> 70#include <sys/mman.h> 71 72#include <netinet/in.h> 73#include <netinet/in_systm.h> 74#include <netinet/ip.h> 75#include <netinet/tcp.h> 76 77#define FTP_NAMES 78#include <arpa/ftp.h> 79#include <arpa/inet.h> 80#include <arpa/telnet.h> 81 82#include <bsd_auth.h> 83#include <ctype.h> 84#include <dirent.h> 85#include <errno.h> 86#include <fcntl.h> 87#include <glob.h> 88#include <limits.h> 89#include <login_cap.h> 90#include <netdb.h> 91#include <pwd.h> 92#include <signal.h> 93#include <stdarg.h> 94#include <stdio.h> 95#include <stdlib.h> 96#include <string.h> 97#include <syslog.h> 98#include <time.h> 99#include <vis.h> 100#include <unistd.h> 101#include <util.h> 102#include <utmp.h> 103#include <poll.h> 104 105#if defined(TCPWRAPPERS) 106#include <tcpd.h> 107#endif /* TCPWRAPPERS */ 108 109#include "pathnames.h" 110#include "monitor.h" 111#include "extern.h" 112 113extern off_t restart_point; 114extern char cbuf[]; 115 116union sockunion ctrl_addr; 117union sockunion data_source; 118union sockunion data_dest; 119union sockunion his_addr; 120union sockunion pasv_addr; 121 122sigset_t allsigs; 123 124int daemon_mode = 0; 125int data; 126int logged_in; 127struct passwd *pw; 128int debug = 0; 129int timeout = 900; /* timeout after 15 minutes of inactivity */ 130int maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */ 131int logging; 132int anon_ok = 1; 133int anon_only = 0; 134int multihome = 0; 135int guest; 136int stats; 137int statfd = -1; 138int portcheck = 1; 139int dochroot; 140int type; 141int form; 142int stru; /* avoid C keyword */ 143int mode; 144int doutmp = 0; /* update utmp file */ 145int usedefault = 1; /* for data transfers */ 146int pdata = -1; /* for passive mode */ 147int family = AF_UNSPEC; 148volatile sig_atomic_t transflag; 149off_t file_size; 150off_t byte_count; 151#if !defined(CMASK) || CMASK == 0 152#undef CMASK 153#define CMASK 022 154#endif 155mode_t defumask = CMASK; /* default umask value */ 156int umaskchange = 1; /* allow user to change umask value. */ 157char tmpline[7]; 158char hostname[MAXHOSTNAMELEN]; 159char remotehost[MAXHOSTNAMELEN]; 160char dhostname[MAXHOSTNAMELEN]; 161char *guestpw; 162char ttyline[20]; 163#if 0 164char *tty = ttyline; /* for klogin */ 165#endif 166static struct utmp utmp; /* for utmp */ 167static login_cap_t *lc; 168static auth_session_t *as; 169static volatile sig_atomic_t recvurg; 170 171#if defined(TCPWRAPPERS) 172int allow_severity = LOG_INFO; 173int deny_severity = LOG_NOTICE; 174#endif /* TCPWRAPPERS */ 175 176char *ident = NULL; 177 178 179int epsvall = 0; 180 181/* 182 * Timeout intervals for retrying connections 183 * to hosts that don't accept PORT cmds. This 184 * is a kludge, but given the problems with TCP... 185 */ 186#define SWAITMAX 90 /* wait at most 90 seconds */ 187#define SWAITINT 5 /* interval between retries */ 188 189int swaitmax = SWAITMAX; 190int swaitint = SWAITINT; 191 192#ifdef HASSETPROCTITLE 193char proctitle[BUFSIZ]; /* initial part of title */ 194#endif /* HASSETPROCTITLE */ 195 196#define LOGCMD(cmd, file) \ 197 if (logging > 1) \ 198 syslog(LOG_INFO,"%s %s%s", cmd, \ 199 *(file) == '/' ? "" : curdir(), file); 200#define LOGCMD2(cmd, file1, file2) \ 201 if (logging > 1) \ 202 syslog(LOG_INFO,"%s %s%s %s%s", cmd, \ 203 *(file1) == '/' ? "" : curdir(), file1, \ 204 *(file2) == '/' ? "" : curdir(), file2); 205#define LOGBYTES(cmd, file, cnt) \ 206 if (logging > 1) { \ 207 if (cnt == (off_t)-1) \ 208 syslog(LOG_INFO,"%s %s%s", cmd, \ 209 *(file) == '/' ? "" : curdir(), file); \ 210 else \ 211 syslog(LOG_INFO, "%s %s%s = %qd bytes", \ 212 cmd, (*(file) == '/') ? "" : curdir(), file, cnt); \ 213 } 214 215static void ack(char *); 216static void sigurg(int); 217static void myoob(void); 218static int checkuser(char *, char *); 219static FILE *dataconn(char *, off_t, char *); 220static void dolog(struct sockaddr *); 221static char *copy_dir(char *, struct passwd *); 222static char *curdir(void); 223static void end_login(void); 224static FILE *getdatasock(char *); 225static int guniquefd(char *, char **); 226static void lostconn(int); 227static void sigquit(int); 228static int receive_data(FILE *, FILE *); 229static void replydirname(const char *, const char *); 230static int send_data(FILE *, FILE *, off_t, off_t, int); 231static struct passwd * 232 sgetpwnam(char *, struct passwd *); 233static void reapchild(int); 234#if defined(TCPWRAPPERS) 235static int check_host(struct sockaddr *); 236#endif /* TCPWRAPPERS */ 237static void usage(void); 238 239void logxfer(char *, off_t, time_t); 240void set_slave_signals(void); 241 242static char * 243curdir(void) 244{ 245 static char path[MAXPATHLEN+1]; /* path + '/' */ 246 247 if (getcwd(path, sizeof(path)-1) == NULL) 248 return (""); 249 if (path[1] != '\0') /* special case for root dir. */ 250 strlcat(path, "/", sizeof path); 251 /* For guest account, skip / since it's chrooted */ 252 return (guest ? path+1 : path); 253} 254 255char *argstr = "AdDhnlMSt:T:u:UvP46"; 256 257static void 258usage(void) 259{ 260 syslog(LOG_ERR, 261 "usage: ftpd [-46ADdlMnPSU] [-T maxtimeout] [-t timeout] [-u mask]"); 262 exit(2); 263} 264 265int 266main(int argc, char *argv[]) 267{ 268 socklen_t addrlen; 269 int ch, on = 1, tos; 270 char line[LINE_MAX]; 271 FILE *fp; 272 struct hostent *hp; 273 struct sigaction sa; 274 int error = 0; 275 const char *errstr; 276 277 tzset(); /* in case no timezone database in ~ftp */ 278 sigfillset(&allsigs); /* used to block signals while root */ 279 sigemptyset(&sa.sa_mask); 280 sa.sa_flags = SA_RESTART; 281 282 while ((ch = getopt(argc, argv, argstr)) != -1) { 283 switch (ch) { 284 case 'A': 285 anon_only = 1; 286 break; 287 288 case 'd': 289 case 'v': /* deprecated */ 290 debug = 1; 291 break; 292 293 case 'D': 294 daemon_mode = 1; 295 break; 296 297 case 'P': 298 portcheck = 0; 299 break; 300 301 case 'h': /* deprecated */ 302 break; 303 304 case 'l': 305 logging++; /* > 1 == extra logging */ 306 break; 307 308 case 'M': 309 multihome = 1; 310 break; 311 312 case 'n': 313 anon_ok = 0; 314 break; 315 316 case 'S': 317 stats = 1; 318 break; 319 320 case 't': 321 timeout = strtonum(optarg, 0, INT_MAX, &errstr); 322 if (errstr) { 323 syslog(LOG_ERR, 324 "%s is a bad value for -t, aborting", 325 optarg); 326 exit(2); 327 } 328 if (maxtimeout < timeout) 329 maxtimeout = timeout; 330 break; 331 332 case 'T': 333 maxtimeout = strtonum(optarg, 0, INT_MAX, 334 &errstr); 335 if (errstr) { 336 syslog(LOG_ERR, 337 "%s is a bad value for -T, aborting", 338 optarg); 339 exit(2); 340 } 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 (*optarg == '\0' || *p != '\0' || val < 0 || 353 (val & ~ACCESSPERMS)) { 354 syslog(LOG_ERR, 355 "%s is a bad value for -u, aborting", 356 optarg); 357 exit(2); 358 } 359 defumask = val; 360 break; 361 } 362 363 case 'U': 364 doutmp = 1; 365 break; 366 367 case '4': 368 family = AF_INET; 369 break; 370 371 case '6': 372 family = AF_INET6; 373 break; 374 375 default: 376 usage(); 377 break; 378 } 379 } 380 381 (void) freopen(_PATH_DEVNULL, "w", stderr); 382 383 /* 384 * LOG_NDELAY sets up the logging connection immediately, 385 * necessary for anonymous ftp's that chroot and can't do it later. 386 */ 387 openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP); 388 389 if (getpwnam(FTPD_PRIVSEP_USER) == NULL) { 390 syslog(LOG_ERR, "privilege separation user %s not found", 391 FTPD_PRIVSEP_USER); 392 exit(1); 393 } 394 endpwent(); 395 396 if (daemon_mode) { 397 int *fds, i, fd; 398 struct pollfd *pfds; 399 struct addrinfo hints, *res, *res0; 400 nfds_t n; 401 402 /* 403 * Detach from parent. 404 */ 405 if (daemon(1, 1) < 0) { 406 syslog(LOG_ERR, "failed to become a daemon"); 407 exit(1); 408 } 409 sa.sa_handler = reapchild; 410 (void) sigaction(SIGCHLD, &sa, NULL); 411 412 memset(&hints, 0, sizeof(hints)); 413 hints.ai_family = family; 414 hints.ai_socktype = SOCK_STREAM; 415 hints.ai_protocol = IPPROTO_TCP; 416 hints.ai_flags = AI_PASSIVE; 417 error = getaddrinfo(NULL, "ftp", &hints, &res0); 418 if (error) { 419 syslog(LOG_ERR, "%s", gai_strerror(error)); 420 exit(1); 421 } 422 423 n = 0; 424 for (res = res0; res; res = res->ai_next) 425 n++; 426 427 fds = calloc(n, sizeof(int)); 428 pfds = calloc(n, sizeof(struct pollfd)); 429 if (!fds || !pfds) { 430 syslog(LOG_ERR, "%s", strerror(errno)); 431 exit(1); 432 } 433 434 /* 435 * Open sockets, bind it to the FTP port, and start 436 * listening. 437 */ 438 n = 0; 439 for (res = res0; res; res = res->ai_next) { 440 fds[n] = socket(res->ai_family, res->ai_socktype, 441 res->ai_protocol); 442 if (fds[n] < 0) 443 continue; 444 445 if (setsockopt(fds[n], SOL_SOCKET, SO_REUSEADDR, 446 &on, sizeof(on)) < 0) { 447 close(fds[n]); 448 fds[n] = -1; 449 continue; 450 } 451 452 if (bind(fds[n], res->ai_addr, res->ai_addrlen) < 0) { 453 close(fds[n]); 454 fds[n] = -1; 455 continue; 456 } 457 if (listen(fds[n], 32) < 0) { 458 close(fds[n]); 459 fds[n] = -1; 460 continue; 461 } 462 463 pfds[n].fd = fds[n]; 464 pfds[n].events = POLLIN; 465 n++; 466 } 467 freeaddrinfo(res0); 468 469 if (n == 0) { 470 syslog(LOG_ERR, "could not open control socket"); 471 exit(1); 472 } 473 474 /* Stash pid in pidfile */ 475 if (pidfile(NULL)) 476 syslog(LOG_ERR, "can't open pidfile: %m"); 477 /* 478 * Loop forever accepting connection requests and forking off 479 * children to handle them. 480 */ 481 while (1) { 482 if (poll(pfds, n, INFTIM) < 0) { 483 if (errno == EINTR) 484 continue; 485 syslog(LOG_ERR, "poll: %m"); 486 exit(1); 487 } 488 for (i = 0; i < n; i++) 489 if (pfds[i].revents & POLLIN) { 490 addrlen = sizeof(his_addr); 491 fd = accept(pfds[i].fd, 492 (struct sockaddr *)&his_addr, 493 &addrlen); 494 if (fd != -1) { 495 if (fork() == 0) 496 goto child; 497 close(fd); 498 } 499 } 500 } 501 502 child: 503 /* child */ 504 (void)dup2(fd, STDIN_FILENO); 505 (void)dup2(fd, STDOUT_FILENO); 506 for (i = 0; i < n; i++) 507 close(fds[i]); 508#if defined(TCPWRAPPERS) 509 /* ..in the child. */ 510 if (!check_host((struct sockaddr *)&his_addr)) 511 exit(1); 512#endif /* TCPWRAPPERS */ 513 } else { 514 addrlen = sizeof(his_addr); 515 if (getpeername(0, (struct sockaddr *)&his_addr, 516 &addrlen) < 0) { 517 /* syslog(LOG_ERR, "getpeername (%s): %m", argv[0]); */ 518 exit(1); 519 } 520 } 521 522 /* set this here so klogin can use it... */ 523 (void)snprintf(ttyline, sizeof(ttyline), "ftp%ld", (long)getpid()); 524 525 set_slave_signals(); 526 527 addrlen = sizeof(ctrl_addr); 528 if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) { 529 syslog(LOG_ERR, "getsockname: %m"); 530 exit(1); 531 } 532 if (his_addr.su_family == AF_INET6 && 533 IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr)) { 534#if 1 535 /* 536 * IPv4 control connection arrived to AF_INET6 socket. 537 * I hate to do this, but this is the easiest solution. 538 */ 539 union sockunion tmp_addr; 540 const int off = sizeof(struct in6_addr) - sizeof(struct in_addr); 541 542 tmp_addr = his_addr; 543 memset(&his_addr, 0, sizeof(his_addr)); 544 his_addr.su_sin.sin_family = AF_INET; 545 his_addr.su_sin.sin_len = sizeof(his_addr.su_sin); 546 memcpy(&his_addr.su_sin.sin_addr, 547 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 548 sizeof(his_addr.su_sin.sin_addr)); 549 his_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 550 551 tmp_addr = ctrl_addr; 552 memset(&ctrl_addr, 0, sizeof(ctrl_addr)); 553 ctrl_addr.su_sin.sin_family = AF_INET; 554 ctrl_addr.su_sin.sin_len = sizeof(ctrl_addr.su_sin); 555 memcpy(&ctrl_addr.su_sin.sin_addr, 556 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 557 sizeof(ctrl_addr.su_sin.sin_addr)); 558 ctrl_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 559#else 560 while (fgets(line, sizeof(line), fd) != NULL) { 561 line[strcspn(line, "\n")] = '\0'; 562 lreply(530, "%s", line); 563 } 564 (void) fflush(stdout); 565 (void) close(fd); 566 reply(530, 567 "Connection from IPv4 mapped address is not supported."); 568 exit(0); 569#endif 570 } 571#ifdef IP_TOS 572 if (his_addr.su_family == AF_INET) { 573 tos = IPTOS_LOWDELAY; 574 if (setsockopt(0, IPPROTO_IP, IP_TOS, &tos, 575 sizeof(int)) < 0) 576 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 577 } 578#endif 579 data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1); 580 581 /* Try to handle urgent data inline */ 582#ifdef SO_OOBINLINE 583 if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, &on, sizeof(on)) < 0) 584 syslog(LOG_ERR, "setsockopt: %m"); 585#endif 586 587 dolog((struct sockaddr *)&his_addr); 588 589 /* 590 * Set up default state 591 */ 592 data = -1; 593 type = TYPE_A; 594 form = FORM_N; 595 stru = STRU_F; 596 mode = MODE_S; 597 tmpline[0] = '\0'; 598 599 /* If logins are disabled, print out the message. */ 600 if ((fp = fopen(_PATH_NOLOGIN, "r")) != NULL) { 601 while (fgets(line, sizeof(line), fp) != NULL) { 602 line[strcspn(line, "\n")] = '\0'; 603 lreply(530, "%s", line); 604 } 605 (void) fflush(stdout); 606 (void) fclose(fp); 607 reply(530, "System not available."); 608 exit(0); 609 } 610 if ((fp = fopen(_PATH_FTPWELCOME, "r")) != NULL) { 611 while (fgets(line, sizeof(line), fp) != NULL) { 612 line[strcspn(line, "\n")] = '\0'; 613 lreply(220, "%s", line); 614 } 615 (void) fflush(stdout); 616 (void) fclose(fp); 617 /* reply(220,) must follow */ 618 } 619 (void) gethostname(hostname, sizeof(hostname)); 620 621 /* Make sure hostname is fully qualified. */ 622 hp = gethostbyname(hostname); 623 if (hp != NULL) 624 strlcpy(hostname, hp->h_name, sizeof(hostname)); 625 626 if (multihome) { 627 error = getnameinfo((struct sockaddr *)&ctrl_addr, 628 ctrl_addr.su_len, dhostname, sizeof(dhostname), NULL, 0, 0); 629 } 630 631 if (error != 0) 632 reply(220, "FTP server ready."); 633 else 634 reply(220, "%s FTP server ready.", 635 (multihome ? dhostname : hostname)); 636 637 monitor_init(); 638 639 for (;;) 640 (void) yyparse(); 641 /* NOTREACHED */ 642} 643 644/* 645 * Signal handlers. 646 */ 647/*ARGSUSED*/ 648static void 649lostconn(int signo) 650{ 651 struct syslog_data sdata = SYSLOG_DATA_INIT; 652 653 sdata.log_fac = LOG_FTP; 654 if (debug) 655 syslog_r(LOG_DEBUG, &sdata, "lost connection"); 656 dologout(1); 657} 658 659static void 660sigquit(int signo) 661{ 662 struct syslog_data sdata = SYSLOG_DATA_INIT; 663 664 sdata.log_fac = LOG_FTP; 665 syslog_r(LOG_DEBUG, &sdata, "got signal %s", sys_signame[signo]); 666 dologout(1); 667} 668 669/* 670 * Save the result of a getpwnam. Used for USER command, since 671 * the data returned must not be clobbered by any other command 672 * (e.g., globbing). 673 */ 674static struct passwd * 675sgetpwnam(char *name, struct passwd *pw) 676{ 677 static struct passwd *save; 678 struct passwd *old; 679 680 if (pw == NULL && (pw = getpwnam(name)) == NULL) 681 return (NULL); 682 old = save; 683 save = pw_dup(pw); 684 if (save == NULL) { 685 perror_reply(421, "Local resource failure: malloc"); 686 dologout(1); 687 /* NOTREACHED */ 688 } 689 if (old) { 690 memset(old->pw_passwd, 0, strlen(old->pw_passwd)); 691 free(old); 692 } 693 return (save); 694} 695 696static int login_attempts; /* number of failed login attempts */ 697static int askpasswd; /* had user command, ask for passwd */ 698static char curname[MAXLOGNAME]; /* current USER name */ 699 700/* 701 * USER command. 702 * Sets global passwd pointer pw if named account exists and is acceptable; 703 * sets askpasswd if a PASS command is expected. If logged in previously, 704 * need to reset state. If name is "ftp" or "anonymous", the name is not in 705 * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return. 706 * If account doesn't exist, ask for passwd anyway. Otherwise, check user 707 * requesting login privileges. Disallow anyone who does not have a standard 708 * shell as returned by getusershell(). Disallow anyone mentioned in the file 709 * _PATH_FTPUSERS to allow people such as root and uucp to be avoided. 710 */ 711void 712user(char *name) 713{ 714 char *cp, *shell, *style, *host; 715 char *class = NULL; 716 717 if (logged_in) { 718 kill_slave("user already logged in"); 719 end_login(); 720 } 721 722 /* Close session from previous user if there was one. */ 723 if (as) { 724 auth_close(as); 725 as = NULL; 726 } 727 if (lc) { 728 login_close(lc); 729 lc = NULL; 730 } 731 732 if ((style = strchr(name, ':')) != NULL) 733 *style++ = 0; 734 735 guest = 0; 736 askpasswd = 0; 737 host = multihome ? dhostname : hostname; 738 if (anon_ok && 739 (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0)) { 740 if (checkuser(_PATH_FTPUSERS, "ftp") || 741 checkuser(_PATH_FTPUSERS, "anonymous")) 742 reply(530, "User %s access denied.", name); 743 else if ((pw = sgetpwnam("ftp", NULL)) != NULL) { 744 if ((lc = login_getclass(pw->pw_class)) == NULL || 745 (as = auth_open()) == NULL || 746 auth_setpwd(as, pw) != 0 || 747 auth_setoption(as, "FTPD_HOST", host) < 0) { 748 if (as) { 749 auth_close(as); 750 as = NULL; 751 } 752 if (lc) { 753 login_close(lc); 754 lc = NULL; 755 } 756 reply(421, "Local resource failure"); 757 return; 758 } 759 guest = 1; 760 askpasswd = 1; 761 reply(331, 762 "Guest login ok, send your email address as password."); 763 } else 764 reply(530, "User %s unknown.", name); 765 if (!askpasswd && logging) 766 syslog(LOG_NOTICE, 767 "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost); 768 return; 769 } 770 771 shell = _PATH_BSHELL; 772 if ((pw = sgetpwnam(name, NULL))) { 773 class = pw->pw_class; 774 if (pw->pw_shell != NULL && *pw->pw_shell != '\0') 775 shell = pw->pw_shell; 776 while ((cp = getusershell()) != NULL) 777 if (strcmp(cp, shell) == 0) 778 break; 779 shell = cp; 780 endusershell(); 781 } 782 783 /* Get login class; if invalid style treat like unknown user. */ 784 lc = login_getclass(class); 785 if (lc && (style = login_getstyle(lc, style, "auth-ftp")) == NULL) { 786 login_close(lc); 787 lc = NULL; 788 pw = NULL; 789 } 790 791 /* Do pre-authentication setup. */ 792 if (lc && ((as = auth_open()) == NULL || 793 (pw != NULL && auth_setpwd(as, pw) != 0) || 794 auth_setitem(as, AUTHV_STYLE, style) < 0 || 795 auth_setitem(as, AUTHV_NAME, name) < 0 || 796 auth_setitem(as, AUTHV_CLASS, class) < 0 || 797 auth_setoption(as, "login", "yes") < 0 || 798 auth_setoption(as, "notickets", "yes") < 0 || 799 auth_setoption(as, "FTPD_HOST", host) < 0)) { 800 if (as) { 801 auth_close(as); 802 as = NULL; 803 } 804 login_close(lc); 805 lc = NULL; 806 reply(421, "Local resource failure"); 807 return; 808 } 809 if (logging) 810 strlcpy(curname, name, sizeof(curname)); 811 812 dochroot = (lc && login_getcapbool(lc, "ftp-chroot", 0)) || 813 checkuser(_PATH_FTPCHROOT, name); 814 if (anon_only && !dochroot) { 815 reply(530, "User %s access denied.", name); 816 return; 817 } 818 if (pw) { 819 if ((!shell && !dochroot) || checkuser(_PATH_FTPUSERS, name)) { 820 reply(530, "User %s access denied.", name); 821 if (logging) 822 syslog(LOG_NOTICE, 823 "FTP LOGIN REFUSED FROM %s, %s", 824 remotehost, name); 825 pw = NULL; 826 return; 827 } 828 } 829 830 if (as != NULL && (cp = auth_challenge(as)) != NULL) 831 reply(331, "%s", cp); 832 else 833 reply(331, "Password required for %s.", name); 834 835 askpasswd = 1; 836 /* 837 * Delay before reading passwd after first failed 838 * attempt to slow down passwd-guessing programs. 839 */ 840 if (login_attempts) 841 sleep((unsigned) login_attempts); 842} 843 844/* 845 * Check if a user is in the file "fname" 846 */ 847static int 848checkuser(char *fname, char *name) 849{ 850 FILE *fp; 851 int found = 0; 852 char *p, line[BUFSIZ]; 853 854 if ((fp = fopen(fname, "r")) != NULL) { 855 while (fgets(line, sizeof(line), fp) != NULL) 856 if ((p = strchr(line, '\n')) != NULL) { 857 *p = '\0'; 858 if (line[0] == '#') 859 continue; 860 if (strcmp(line, name) == 0) { 861 found = 1; 862 break; 863 } 864 } 865 (void) fclose(fp); 866 } 867 return (found); 868} 869 870/* 871 * Terminate login as previous user, if any, resetting state; 872 * used when USER command is given or login fails. 873 */ 874static void 875end_login(void) 876{ 877 sigprocmask (SIG_BLOCK, &allsigs, NULL); 878 if (logged_in) { 879 ftpdlogwtmp(ttyline, "", ""); 880 if (doutmp) 881 ftpd_logout(utmp.ut_line); 882 } 883 reply(530, "Please reconnect to work as another user"); 884 _exit(0); 885} 886 887enum auth_ret 888pass(char *passwd) 889{ 890 int authok; 891 unsigned int flags; 892 FILE *fp; 893 static char homedir[MAXPATHLEN]; 894 char *motd, *dir, rootdir[MAXPATHLEN]; 895 size_t sz_pw_dir; 896 897 if (logged_in || askpasswd == 0) { 898 reply(503, "Login with USER first."); 899 return (AUTH_FAILED); 900 } 901 askpasswd = 0; 902 if (!guest) { /* "ftp" is only account allowed no password */ 903 authok = 0; 904 if (pw == NULL || pw->pw_passwd[0] == '\0') { 905 useconds_t us; 906 907 /* Sleep between 1 and 3 seconds to emulate a crypt. */ 908 us = arc4random_uniform(3000000); 909 usleep(us); 910 if (as != NULL) { 911 auth_close(as); 912 as = NULL; 913 } 914 } else { 915 authok = auth_userresponse(as, passwd, 0); 916 as = NULL; 917 } 918 if (authok == 0) { 919 reply(530, "Login incorrect."); 920 if (logging) 921 syslog(LOG_NOTICE, 922 "FTP LOGIN FAILED FROM %s, %s", 923 remotehost, curname); 924 pw = NULL; 925 if (login_attempts++ >= 5) { 926 syslog(LOG_NOTICE, 927 "repeated login failures from %s", 928 remotehost); 929 kill_slave("repeated login failures"); 930 _exit(0); 931 } 932 return (AUTH_FAILED); 933 } 934 } else if (lc != NULL) { 935 /* Save anonymous' password. */ 936 if (guestpw != NULL) 937 free(guestpw); 938 guestpw = strdup(passwd); 939 if (guestpw == NULL) { 940 kill_slave("out of mem"); 941 fatal("Out of memory."); 942 } 943 944 authok = auth_approval(as, lc, pw->pw_name, "ftp"); 945 auth_close(as); 946 as = NULL; 947 if (authok == 0) { 948 syslog(LOG_INFO|LOG_AUTH, 949 "FTP LOGIN FAILED (HOST) as %s: approval failure.", 950 pw->pw_name); 951 reply(530, "Approval failure."); 952 kill_slave("approval failure"); 953 _exit(0); 954 } 955 } else { 956 syslog(LOG_INFO|LOG_AUTH, 957 "FTP LOGIN CLASS %s MISSING for %s: approval failure.", 958 pw->pw_class, pw->pw_name); 959 reply(530, "Permission denied."); 960 kill_slave("permission denied"); 961 _exit(0); 962 } 963 964 if (monitor_post_auth() == 1) { 965 /* Post-auth monitor process */ 966 logged_in = 1; 967 return (AUTH_MONITOR); 968 } 969 970 login_attempts = 0; /* this time successful */ 971 /* set umask via setusercontext() unless -u flag was given. */ 972 flags = LOGIN_SETGROUP|LOGIN_SETPRIORITY|LOGIN_SETRESOURCES; 973 if (umaskchange) 974 flags |= LOGIN_SETUMASK; 975 else 976 (void) umask(defumask); 977 if (setusercontext(lc, pw, (uid_t)0, flags) != 0) { 978 perror_reply(421, "Local resource failure: setusercontext"); 979 syslog(LOG_NOTICE, "setusercontext: %m"); 980 dologout(1); 981 /* NOTREACHED */ 982 } 983 984 /* open wtmp before chroot */ 985 ftpdlogwtmp(ttyline, pw->pw_name, remotehost); 986 987 /* open utmp before chroot */ 988 if (doutmp) { 989 memset((void *)&utmp, 0, sizeof(utmp)); 990 (void)time(&utmp.ut_time); 991 (void)strncpy(utmp.ut_name, pw->pw_name, sizeof(utmp.ut_name)); 992 (void)strncpy(utmp.ut_host, remotehost, sizeof(utmp.ut_host)); 993 (void)strncpy(utmp.ut_line, ttyline, sizeof(utmp.ut_line)); 994 ftpd_login(&utmp); 995 } 996 997 /* open stats file before chroot */ 998 if (guest && (stats == 1) && (statfd < 0)) 999 if ((statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND)) < 0) 1000 stats = 0; 1001 1002 logged_in = 1; 1003 1004 if ((dir = login_getcapstr(lc, "ftp-dir", NULL, NULL))) { 1005 char *newdir; 1006 1007 newdir = copy_dir(dir, pw); 1008 if (newdir == NULL) { 1009 perror_reply(421, "Local resource failure: malloc"); 1010 dologout(1); 1011 /* NOTREACHED */ 1012 } 1013 pw->pw_dir = newdir; 1014 pw = sgetpwnam(NULL, pw); 1015 free(dir); 1016 free(newdir); 1017 } 1018 1019 /* make sure pw->pw_dir is big enough to hold "/" */ 1020 sz_pw_dir = strlen(pw->pw_dir) + 1; 1021 if (sz_pw_dir < 2) { 1022 pw->pw_dir = "/"; 1023 pw = sgetpwnam(NULL, pw); 1024 sz_pw_dir = 2; 1025 } 1026 1027 if (guest || dochroot) { 1028 if (multihome && guest) { 1029 struct stat ts; 1030 1031 /* Compute root directory. */ 1032 snprintf(rootdir, sizeof(rootdir), "%s/%s", 1033 pw->pw_dir, dhostname); 1034 if (stat(rootdir, &ts) < 0) { 1035 snprintf(rootdir, sizeof(rootdir), "%s/%s", 1036 pw->pw_dir, hostname); 1037 } 1038 } else 1039 strlcpy(rootdir, pw->pw_dir, sizeof(rootdir)); 1040 } 1041 if (guest) { 1042 /* 1043 * We MUST do a chdir() after the chroot. Otherwise 1044 * the old current directory will be accessible as "." 1045 * outside the new root! 1046 */ 1047 if (chroot(rootdir) < 0 || chdir("/") < 0) { 1048 reply(550, "Can't set guest privileges."); 1049 goto bad; 1050 } 1051 strlcpy(pw->pw_dir, "/", sz_pw_dir); 1052 if (setenv("HOME", "/", 1) == -1) { 1053 reply(550, "Can't setup environment."); 1054 goto bad; 1055 } 1056 } else if (dochroot) { 1057 if (chroot(rootdir) < 0 || chdir("/") < 0) { 1058 reply(550, "Can't change root."); 1059 goto bad; 1060 } 1061 strlcpy(pw->pw_dir, "/", sz_pw_dir); 1062 if (setenv("HOME", "/", 1) == -1) { 1063 reply(550, "Can't setup environment."); 1064 goto bad; 1065 } 1066 } else if (chdir(pw->pw_dir) < 0) { 1067 if (chdir("/") < 0) { 1068 reply(530, "User %s: can't change directory to %s.", 1069 pw->pw_name, pw->pw_dir); 1070 goto bad; 1071 } else 1072 lreply(230, "No directory! Logging in with home=/"); 1073 } 1074 if (setegid(pw->pw_gid) < 0 || setgid(pw->pw_gid) < 0) { 1075 reply(550, "Can't set gid."); 1076 goto bad; 1077 } 1078 if (seteuid(pw->pw_uid) < 0 || setuid(pw->pw_uid) < 0) { 1079 reply(550, "Can't set uid."); 1080 goto bad; 1081 } 1082 sigprocmask(SIG_UNBLOCK, &allsigs, NULL); 1083 1084 /* 1085 * Set home directory so that use of ~ (tilde) works correctly. 1086 */ 1087 if (getcwd(homedir, MAXPATHLEN) != NULL) { 1088 if (setenv("HOME", homedir, 1) == -1) { 1089 reply(550, "Can't setup environment."); 1090 goto bad; 1091 } 1092 } 1093 1094 /* 1095 * Display a login message, if it exists. 1096 * N.B. reply(230,) must follow the message. 1097 */ 1098 motd = login_getcapstr(lc, "welcome", NULL, NULL); 1099 if ((fp = fopen(motd ? motd : _PATH_FTPLOGINMESG, "r")) != NULL) { 1100 char line[LINE_MAX]; 1101 1102 while (fgets(line, sizeof(line), fp) != NULL) { 1103 line[strcspn(line, "\n")] = '\0'; 1104 lreply(230, "%s", line); 1105 } 1106 (void) fflush(stdout); 1107 (void) fclose(fp); 1108 } 1109 if (motd != NULL) 1110 free(motd); 1111 if (guest) { 1112 if (ident != NULL) 1113 free(ident); 1114 ident = strdup(passwd); 1115 if (ident == NULL) 1116 fatal("Ran out of memory."); 1117 reply(230, "Guest login ok, access restrictions apply."); 1118#ifdef HASSETPROCTITLE 1119 snprintf(proctitle, sizeof(proctitle), 1120 "%s: anonymous/%.*s", remotehost, 1121 (int)(sizeof(proctitle) - sizeof(remotehost) - 1122 sizeof(": anonymous/")), passwd); 1123 setproctitle("%s", proctitle); 1124#endif /* HASSETPROCTITLE */ 1125 if (logging) 1126 syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s", 1127 remotehost, passwd); 1128 } else { 1129 reply(230, "User %s logged in.", pw->pw_name); 1130#ifdef HASSETPROCTITLE 1131 snprintf(proctitle, sizeof(proctitle), 1132 "%s: %s", remotehost, pw->pw_name); 1133 setproctitle("%s", proctitle); 1134#endif /* HASSETPROCTITLE */ 1135 if (logging) 1136 syslog(LOG_INFO, "FTP LOGIN FROM %s as %s", 1137 remotehost, pw->pw_name); 1138 } 1139 login_close(lc); 1140 lc = NULL; 1141 return (AUTH_SLAVE); 1142bad: 1143 /* Forget all about it... */ 1144 login_close(lc); 1145 lc = NULL; 1146 end_login(); 1147 return (AUTH_FAILED); 1148} 1149 1150void 1151retrieve(char *cmd, char *name) 1152{ 1153 FILE *fin, *dout; 1154 struct stat st; 1155 int (*closefunc)(FILE *); 1156 time_t start; 1157 1158 if (cmd == 0) { 1159 fin = fopen(name, "r"), closefunc = fclose; 1160 st.st_size = 0; 1161 } else { 1162 char line[BUFSIZ]; 1163 1164 (void) snprintf(line, sizeof(line), cmd, name); 1165 name = line; 1166 fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose; 1167 st.st_size = -1; 1168 st.st_blksize = BUFSIZ; 1169 } 1170 if (fin == NULL) { 1171 if (errno != 0) { 1172 perror_reply(550, name); 1173 if (cmd == 0) { 1174 LOGCMD("get", name); 1175 } 1176 } 1177 return; 1178 } 1179 byte_count = -1; 1180 if (cmd == 0 && (fstat(fileno(fin), &st) < 0 || !S_ISREG(st.st_mode))) { 1181 reply(550, "%s: not a plain file.", name); 1182 goto done; 1183 } 1184 if (restart_point) { 1185 if (type == TYPE_A) { 1186 off_t i, n; 1187 int c; 1188 1189 n = restart_point; 1190 i = 0; 1191 while (i++ < n) { 1192 if ((c = getc(fin)) == EOF) { 1193 if (ferror(fin)) { 1194 perror_reply(550, name); 1195 goto done; 1196 } else 1197 break; 1198 } 1199 if (c == '\n') 1200 i++; 1201 } 1202 } else if (lseek(fileno(fin), restart_point, SEEK_SET) < 0) { 1203 perror_reply(550, name); 1204 goto done; 1205 } 1206 } 1207 dout = dataconn(name, st.st_size, "w"); 1208 if (dout == NULL) 1209 goto done; 1210 time(&start); 1211 send_data(fin, dout, (off_t)st.st_blksize, st.st_size, 1212 (restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode))); 1213 if ((cmd == 0) && stats) 1214 logxfer(name, byte_count, start); 1215 (void) fclose(dout); 1216 data = -1; 1217done: 1218 if (pdata >= 0) 1219 (void) close(pdata); 1220 pdata = -1; 1221 if (cmd == 0) 1222 LOGBYTES("get", name, byte_count); 1223 (*closefunc)(fin); 1224} 1225 1226void 1227store(char *name, char *mode, int unique) 1228{ 1229 FILE *fout, *din; 1230 int (*closefunc)(FILE *); 1231 struct stat st; 1232 int fd; 1233 1234 if (restart_point && *mode != 'a') 1235 mode = "r+"; 1236 1237 if (unique && stat(name, &st) == 0) { 1238 char *nam; 1239 1240 fd = guniquefd(name, &nam); 1241 if (fd == -1) { 1242 LOGCMD(*mode == 'w' ? "put" : "append", name); 1243 return; 1244 } 1245 name = nam; 1246 fout = fdopen(fd, mode); 1247 } else 1248 fout = fopen(name, mode); 1249 1250 closefunc = fclose; 1251 if (fout == NULL) { 1252 perror_reply(553, name); 1253 LOGCMD(*mode == 'w' ? "put" : "append", name); 1254 return; 1255 } 1256 byte_count = -1; 1257 if (restart_point) { 1258 if (type == TYPE_A) { 1259 off_t i, n; 1260 int c; 1261 1262 n = restart_point; 1263 i = 0; 1264 while (i++ < n) { 1265 if ((c = getc(fout)) == EOF) { 1266 if (ferror(fout)) { 1267 perror_reply(550, name); 1268 goto done; 1269 } else 1270 break; 1271 } 1272 if (c == '\n') 1273 i++; 1274 } 1275 /* 1276 * We must do this seek to "current" position 1277 * because we are changing from reading to 1278 * writing. 1279 */ 1280 if (fseek(fout, 0L, SEEK_CUR) < 0) { 1281 perror_reply(550, name); 1282 goto done; 1283 } 1284 } else if (lseek(fileno(fout), restart_point, SEEK_SET) < 0) { 1285 perror_reply(550, name); 1286 goto done; 1287 } 1288 } 1289 din = dataconn(name, (off_t)-1, "r"); 1290 if (din == NULL) 1291 goto done; 1292 if (receive_data(din, fout) == 0) { 1293 if (unique) 1294 reply(226, "Transfer complete (unique file name:%s).", 1295 name); 1296 else 1297 reply(226, "Transfer complete."); 1298 } 1299 (void) fclose(din); 1300 data = -1; 1301 pdata = -1; 1302done: 1303 LOGBYTES(*mode == 'w' ? "put" : "append", name, byte_count); 1304 (*closefunc)(fout); 1305} 1306 1307static FILE * 1308getdatasock(char *mode) 1309{ 1310 int on = 1, s, t, tries; 1311 1312 if (data >= 0) 1313 return (fdopen(data, mode)); 1314 sigprocmask (SIG_BLOCK, &allsigs, NULL); 1315 s = monitor_socket(ctrl_addr.su_family); 1316 if (s < 0) 1317 goto bad; 1318 if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, 1319 &on, sizeof(on)) < 0) 1320 goto bad; 1321 /* anchor socket to avoid multi-homing problems */ 1322 data_source = ctrl_addr; 1323 data_source.su_port = htons(20); /* ftp-data port */ 1324 for (tries = 1; ; tries++) { 1325 if (monitor_bind(s, (struct sockaddr *)&data_source, 1326 data_source.su_len) >= 0) 1327 break; 1328 if (errno != EADDRINUSE || tries > 10) 1329 goto bad; 1330 sleep((unsigned int)tries); 1331 } 1332 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1333 1334#ifdef IP_TOS 1335 if (ctrl_addr.su_family == AF_INET) { 1336 on = IPTOS_THROUGHPUT; 1337 if (setsockopt(s, IPPROTO_IP, IP_TOS, &on, 1338 sizeof(int)) < 0) 1339 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 1340 } 1341#endif 1342#ifdef TCP_NOPUSH 1343 /* 1344 * Turn off push flag to keep sender TCP from sending short packets 1345 * at the boundaries of each write(). Should probably do a SO_SNDBUF 1346 * to set the send buffer size as well, but that may not be desirable 1347 * in heavy-load situations. 1348 */ 1349 on = 1; 1350 if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, &on, sizeof(on)) < 0) 1351 syslog(LOG_WARNING, "setsockopt (TCP_NOPUSH): %m"); 1352#endif 1353#ifdef SO_SNDBUF 1354 on = 65536; 1355 if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, &on, sizeof(on)) < 0) 1356 syslog(LOG_WARNING, "setsockopt (SO_SNDBUF): %m"); 1357#endif 1358 1359 return (fdopen(s, mode)); 1360bad: 1361 /* Return the real value of errno (close may change it) */ 1362 t = errno; 1363 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1364 if (s >= 0) 1365 (void) close(s); 1366 errno = t; 1367 return (NULL); 1368} 1369 1370static FILE * 1371dataconn(char *name, off_t size, char *mode) 1372{ 1373 char sizebuf[32]; 1374 FILE *file = NULL; 1375 int retry = 0; 1376 in_port_t *p; 1377 u_char *fa, *ha; 1378 size_t alen; 1379 int error; 1380 1381 file_size = size; 1382 byte_count = 0; 1383 if (size != (off_t) -1) { 1384 (void) snprintf(sizebuf, sizeof(sizebuf), " (%qd bytes)", 1385 size); 1386 } else 1387 sizebuf[0] = '\0'; 1388 if (pdata >= 0) { 1389 union sockunion from; 1390 int s; 1391 socklen_t fromlen = sizeof(from); 1392 1393 (void) alarm ((unsigned) timeout); 1394 s = accept(pdata, (struct sockaddr *)&from, &fromlen); 1395 (void) alarm (0); 1396 if (s < 0) { 1397 reply(425, "Can't open data connection."); 1398 (void) close(pdata); 1399 pdata = -1; 1400 return (NULL); 1401 } 1402 switch (from.su_family) { 1403 case AF_INET: 1404 p = (in_port_t *)&from.su_sin.sin_port; 1405 fa = (u_char *)&from.su_sin.sin_addr; 1406 ha = (u_char *)&his_addr.su_sin.sin_addr; 1407 alen = sizeof(struct in_addr); 1408 break; 1409 case AF_INET6: 1410 p = (in_port_t *)&from.su_sin6.sin6_port; 1411 fa = (u_char *)&from.su_sin6.sin6_addr; 1412 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1413 alen = sizeof(struct in6_addr); 1414 break; 1415 default: 1416 reply(425, "Can't build data connection: " 1417 "unknown address family"); 1418 (void) close(pdata); 1419 (void) close(s); 1420 pdata = -1; 1421 return (NULL); 1422 } 1423 if (from.su_family != his_addr.su_family || 1424 ntohs(*p) < IPPORT_RESERVED) { 1425 reply(425, "Can't build data connection: " 1426 "address family or port error"); 1427 (void) close(pdata); 1428 (void) close(s); 1429 pdata = -1; 1430 return (NULL); 1431 } 1432 if (portcheck && memcmp(fa, ha, alen) != 0) { 1433 reply(425, "Can't build data connection: " 1434 "illegal port number"); 1435 (void) close(pdata); 1436 (void) close(s); 1437 pdata = -1; 1438 return (NULL); 1439 } 1440 (void) close(pdata); 1441 pdata = s; 1442 reply(150, "Opening %s mode data connection for '%s'%s.", 1443 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1444 return (fdopen(pdata, mode)); 1445 } 1446 if (data >= 0) { 1447 reply(125, "Using existing data connection for '%s'%s.", 1448 name, sizebuf); 1449 usedefault = 1; 1450 return (fdopen(data, mode)); 1451 } 1452 if (usedefault) 1453 data_dest = his_addr; 1454 usedefault = 1; 1455 do { 1456 if (file != NULL) 1457 (void) fclose(file); 1458 file = getdatasock(mode); 1459 if (file == NULL) { 1460 char hbuf[MAXHOSTNAMELEN], pbuf[10]; 1461 1462 error = getnameinfo((struct sockaddr *)&data_source, 1463 data_source.su_len, hbuf, sizeof(hbuf), pbuf, 1464 sizeof(pbuf), NI_NUMERICHOST | NI_NUMERICSERV); 1465 if (error != 0) 1466 reply(425, "Can't create data socket: %s.", 1467 strerror(errno)); 1468 else 1469 reply(425, 1470 "Can't create data socket (%s,%s): %s.", 1471 hbuf, pbuf, strerror(errno)); 1472 return (NULL); 1473 } 1474 1475 /* 1476 * attempt to connect to reserved port on client machine; 1477 * this looks like an attack 1478 */ 1479 switch (data_dest.su_family) { 1480 case AF_INET: 1481 p = (in_port_t *)&data_dest.su_sin.sin_port; 1482 fa = (u_char *)&data_dest.su_sin.sin_addr; 1483 ha = (u_char *)&his_addr.su_sin.sin_addr; 1484 alen = sizeof(struct in_addr); 1485 break; 1486 case AF_INET6: 1487 p = (in_port_t *)&data_dest.su_sin6.sin6_port; 1488 fa = (u_char *)&data_dest.su_sin6.sin6_addr; 1489 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1490 alen = sizeof(struct in6_addr); 1491 break; 1492 default: 1493 reply(425, "Can't build data connection: " 1494 "unknown address family"); 1495 (void) fclose(file); 1496 pdata = -1; 1497 return (NULL); 1498 } 1499 if (data_dest.su_family != his_addr.su_family || 1500 ntohs(*p) < IPPORT_RESERVED || ntohs(*p) == 2049) { /* XXX */ 1501 reply(425, "Can't build data connection: " 1502 "address family or port error"); 1503 (void) fclose(file); 1504 return NULL; 1505 } 1506 if (portcheck && memcmp(fa, ha, alen) != 0) { 1507 reply(435, "Can't build data connection: " 1508 "illegal port number"); 1509 (void) fclose(file); 1510 return NULL; 1511 } 1512 1513 if (connect(fileno(file), (struct sockaddr *)&data_dest, 1514 data_dest.su_len) == 0) { 1515 reply(150, "Opening %s mode data connection for '%s'%s.", 1516 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1517 data = fileno(file); 1518 return (file); 1519 } 1520 if (errno != EADDRINUSE) 1521 break; 1522 sleep((unsigned) swaitint); 1523 retry += swaitint; 1524 } while (retry <= swaitmax); 1525 perror_reply(425, "Can't build data connection"); 1526 (void) fclose(file); 1527 return (NULL); 1528} 1529 1530/* 1531 * Transfer the contents of "instr" to "outstr" peer using the appropriate 1532 * encapsulation of the data subject to Mode, Structure, and Type. 1533 * 1534 * NB: Form isn't handled. 1535 */ 1536static int 1537send_data(FILE *instr, FILE *outstr, off_t blksize, off_t filesize, int isreg) 1538{ 1539 int c, cnt, filefd, netfd; 1540 char *buf, *bp; 1541 size_t len; 1542 1543 transflag++; 1544 switch (type) { 1545 1546 case TYPE_A: 1547 while ((c = getc(instr)) != EOF) { 1548 if (recvurg) 1549 goto got_oob; 1550 byte_count++; 1551 if (c == '\n') { 1552 if (ferror(outstr)) 1553 goto data_err; 1554 (void) putc('\r', outstr); 1555 } 1556 (void) putc(c, outstr); 1557 } 1558 fflush(outstr); 1559 transflag = 0; 1560 if (ferror(instr)) 1561 goto file_err; 1562 if (ferror(outstr)) 1563 goto data_err; 1564 reply(226, "Transfer complete."); 1565 return(0); 1566 1567 case TYPE_I: 1568 case TYPE_L: 1569 /* 1570 * isreg is only set if we are not doing restart and we 1571 * are sending a regular file 1572 */ 1573 netfd = fileno(outstr); 1574 filefd = fileno(instr); 1575 1576 if (isreg && filesize < (off_t)16 * 1024 * 1024) { 1577 size_t fsize = (size_t)filesize; 1578 1579 buf = mmap(0, fsize, PROT_READ, MAP_SHARED, filefd, 1580 (off_t)0); 1581 if (buf == MAP_FAILED) { 1582 syslog(LOG_WARNING, "mmap(%llu): %m", 1583 (unsigned long long)fsize); 1584 goto oldway; 1585 } 1586 bp = buf; 1587 len = fsize; 1588 do { 1589 cnt = write(netfd, bp, len); 1590 if (recvurg) { 1591 munmap(buf, fsize); 1592 goto got_oob; 1593 } 1594 len -= cnt; 1595 bp += cnt; 1596 if (cnt > 0) 1597 byte_count += cnt; 1598 } while(cnt > 0 && len > 0); 1599 1600 transflag = 0; 1601 munmap(buf, fsize); 1602 if (cnt < 0) 1603 goto data_err; 1604 reply(226, "Transfer complete."); 1605 return(0); 1606 } 1607 1608oldway: 1609 if ((buf = malloc((size_t)blksize)) == NULL) { 1610 transflag = 0; 1611 perror_reply(451, "Local resource failure: malloc"); 1612 return(-1); 1613 } 1614 1615 while ((cnt = read(filefd, buf, (size_t)blksize)) > 0 && 1616 write(netfd, buf, cnt) == cnt) 1617 byte_count += cnt; 1618 transflag = 0; 1619 (void)free(buf); 1620 if (cnt != 0) { 1621 if (cnt < 0) 1622 goto file_err; 1623 goto data_err; 1624 } 1625 reply(226, "Transfer complete."); 1626 return(0); 1627 default: 1628 transflag = 0; 1629 reply(550, "Unimplemented TYPE %d in send_data", type); 1630 return(-1); 1631 } 1632 1633data_err: 1634 transflag = 0; 1635 reply(426, "Data connection"); 1636 return(-1); 1637 1638file_err: 1639 transflag = 0; 1640 reply(551, "Error on input file"); 1641 return(-1); 1642 1643got_oob: 1644 myoob(); 1645 recvurg = 0; 1646 transflag = 0; 1647 return(-1); 1648} 1649 1650/* 1651 * Transfer data from peer to "outstr" using the appropriate encapulation of 1652 * the data subject to Mode, Structure, and Type. 1653 * 1654 * N.B.: Form isn't handled. 1655 */ 1656static int 1657receive_data(FILE *instr, FILE *outstr) 1658{ 1659 int c; 1660 int cnt; 1661 char buf[BUFSIZ]; 1662 struct sigaction sa, sa_saved; 1663 volatile int bare_lfs = 0; 1664 1665 transflag++; 1666 switch (type) { 1667 1668 case TYPE_I: 1669 case TYPE_L: 1670 memset(&sa, 0, sizeof(sa)); 1671 sigfillset(&sa.sa_mask); 1672 sa.sa_flags = SA_RESTART; 1673 sa.sa_handler = lostconn; 1674 (void) sigaction(SIGALRM, &sa, &sa_saved); 1675 do { 1676 (void) alarm ((unsigned) timeout); 1677 cnt = read(fileno(instr), buf, sizeof(buf)); 1678 (void) alarm (0); 1679 if (recvurg) 1680 goto got_oob; 1681 1682 if (cnt > 0) { 1683 if (write(fileno(outstr), buf, cnt) != cnt) 1684 goto file_err; 1685 byte_count += cnt; 1686 } 1687 } while (cnt > 0); 1688 (void) sigaction(SIGALRM, &sa_saved, NULL); 1689 if (cnt < 0) 1690 goto data_err; 1691 transflag = 0; 1692 return (0); 1693 1694 case TYPE_E: 1695 reply(553, "TYPE E not implemented."); 1696 transflag = 0; 1697 return (-1); 1698 1699 case TYPE_A: 1700 while ((c = getc(instr)) != EOF) { 1701 if (recvurg) 1702 goto got_oob; 1703 byte_count++; 1704 if (c == '\n') 1705 bare_lfs++; 1706 while (c == '\r') { 1707 if (ferror(outstr)) 1708 goto data_err; 1709 if ((c = getc(instr)) != '\n') { 1710 (void) putc ('\r', outstr); 1711 if (c == '\0' || c == EOF) 1712 goto contin2; 1713 } 1714 } 1715 (void) putc(c, outstr); 1716 contin2: ; 1717 } 1718 fflush(outstr); 1719 if (ferror(instr)) 1720 goto data_err; 1721 if (ferror(outstr)) 1722 goto file_err; 1723 transflag = 0; 1724 if (bare_lfs) { 1725 lreply(226, 1726 "WARNING! %d bare linefeeds received in ASCII mode", 1727 bare_lfs); 1728 printf(" File may not have transferred correctly.\r\n"); 1729 } 1730 return (0); 1731 default: 1732 reply(550, "Unimplemented TYPE %d in receive_data", type); 1733 transflag = 0; 1734 return (-1); 1735 } 1736 1737data_err: 1738 transflag = 0; 1739 reply(426, "Data Connection"); 1740 return (-1); 1741 1742file_err: 1743 transflag = 0; 1744 reply(452, "Error writing file"); 1745 return (-1); 1746 1747got_oob: 1748 myoob(); 1749 recvurg = 0; 1750 transflag = 0; 1751 return (-1); 1752} 1753 1754void 1755statfilecmd(char *filename) 1756{ 1757 FILE *fin; 1758 int c; 1759 int atstart; 1760 char line[LINE_MAX]; 1761 1762 (void)snprintf(line, sizeof(line), "/bin/ls -lgA %s", filename); 1763 fin = ftpd_popen(line, "r"); 1764 if (fin == NULL) { 1765 reply(451, "Local resource failure"); 1766 return; 1767 } 1768 lreply(211, "status of %s:", filename); 1769 atstart = 1; 1770 while ((c = getc(fin)) != EOF) { 1771 if (c == '\n') { 1772 if (ferror(stdout)){ 1773 perror_reply(421, "control connection"); 1774 (void) ftpd_pclose(fin); 1775 dologout(1); 1776 /* NOTREACHED */ 1777 } 1778 if (ferror(fin)) { 1779 perror_reply(551, filename); 1780 (void) ftpd_pclose(fin); 1781 return; 1782 } 1783 (void) putc('\r', stdout); 1784 } 1785 if (atstart && isdigit(c)) 1786 (void) putc(' ', stdout); 1787 (void) putc(c, stdout); 1788 atstart = (c == '\n'); 1789 } 1790 (void) ftpd_pclose(fin); 1791 reply(211, "End of Status"); 1792} 1793 1794void 1795statcmd(void) 1796{ 1797 union sockunion *su; 1798 u_char *a, *p; 1799 char hbuf[MAXHOSTNAMELEN]; 1800 int ispassive; 1801 int error; 1802 1803 lreply(211, "%s FTP server status:", hostname); 1804 error = getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len, 1805 hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST); 1806 printf(" Connected to %s", remotehost); 1807 if (error == 0 && strcmp(remotehost, hbuf) != 0) 1808 printf(" (%s)", hbuf); 1809 printf("\r\n"); 1810 if (logged_in) { 1811 if (guest) 1812 printf(" Logged in anonymously\r\n"); 1813 else 1814 printf(" Logged in as %s\r\n", pw->pw_name); 1815 } else if (askpasswd) 1816 printf(" Waiting for password\r\n"); 1817 else 1818 printf(" Waiting for user name\r\n"); 1819 printf(" TYPE: %s", typenames[type]); 1820 if (type == TYPE_A || type == TYPE_E) 1821 printf(", FORM: %s", formnames[form]); 1822 if (type == TYPE_L) 1823#if NBBY == 8 1824 printf(" %d", NBBY); 1825#else 1826 printf(" %d", bytesize); /* need definition! */ 1827#endif 1828 printf("; STRUcture: %s; transfer MODE: %s\r\n", 1829 strunames[stru], modenames[mode]); 1830 ispassive = 0; 1831 if (data != -1) 1832 printf(" Data connection open\r\n"); 1833 else if (pdata != -1) { 1834 printf(" in Passive mode\r\n"); 1835 su = (union sockunion *)&pasv_addr; 1836 ispassive++; 1837 goto printaddr; 1838 } else if (usedefault == 0) { 1839 size_t alen; 1840 int af, i; 1841 1842 su = (union sockunion *)&data_dest; 1843printaddr: 1844 /* PASV/PORT */ 1845 if (su->su_family == AF_INET) { 1846 if (ispassive) 1847 printf("211- PASV "); 1848 else 1849 printf("211- PORT "); 1850 a = (u_char *)&su->su_sin.sin_addr; 1851 p = (u_char *)&su->su_sin.sin_port; 1852 printf("(%u,%u,%u,%u,%u,%u)\r\n", 1853 a[0], a[1], a[2], a[3], 1854 p[0], p[1]); 1855 } 1856 1857 /* LPSV/LPRT */ 1858 alen = 0; 1859 switch (su->su_family) { 1860 case AF_INET: 1861 a = (u_char *)&su->su_sin.sin_addr; 1862 p = (u_char *)&su->su_sin.sin_port; 1863 alen = sizeof(su->su_sin.sin_addr); 1864 af = 4; 1865 break; 1866 case AF_INET6: 1867 a = (u_char *)&su->su_sin6.sin6_addr; 1868 p = (u_char *)&su->su_sin6.sin6_port; 1869 alen = sizeof(su->su_sin6.sin6_addr); 1870 af = 6; 1871 break; 1872 default: 1873 af = 0; 1874 break; 1875 } 1876 if (af) { 1877 if (ispassive) 1878 printf("211- LPSV "); 1879 else 1880 printf("211- LPRT "); 1881 printf("(%u,%llu", af, (unsigned long long)alen); 1882 for (i = 0; i < alen; i++) 1883 printf(",%u", a[i]); 1884 printf(",%u,%u,%u)\r\n", 2, p[0], p[1]); 1885 } 1886 1887 /* EPRT/EPSV */ 1888 switch (su->su_family) { 1889 case AF_INET: 1890 af = 1; 1891 break; 1892 case AF_INET6: 1893 af = 2; 1894 break; 1895 default: 1896 af = 0; 1897 break; 1898 } 1899 if (af) { 1900 char pbuf[10]; 1901 union sockunion tmp = *su; 1902 1903 if (tmp.su_family == AF_INET6) 1904 tmp.su_sin6.sin6_scope_id = 0; 1905 if (getnameinfo((struct sockaddr *)&tmp, tmp.su_len, 1906 hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), 1907 NI_NUMERICHOST | NI_NUMERICSERV) == 0) { 1908 if (ispassive) 1909 printf("211- EPSV "); 1910 else 1911 printf("211- EPRT "); 1912 printf("(|%u|%s|%s|)\r\n", 1913 af, hbuf, pbuf); 1914 } 1915 } 1916 } else 1917 printf(" No data connection\r\n"); 1918 reply(211, "End of status"); 1919} 1920 1921void 1922fatal(char *s) 1923{ 1924 1925 reply(451, "Error in server: %s", s); 1926 reply(221, "Closing connection due to server error."); 1927 dologout(0); 1928 /* NOTREACHED */ 1929} 1930 1931void 1932reply(int n, const char *fmt, ...) 1933{ 1934 char *buf, *p, *next; 1935 int rval; 1936 va_list ap; 1937 1938 va_start(ap, fmt); 1939 rval = vasprintf(&buf, fmt, ap); 1940 va_end(ap); 1941 if (rval == -1 || buf == NULL) { 1942 printf("421 Local resource failure: malloc\r\n"); 1943 fflush(stdout); 1944 dologout(1); 1945 } 1946 next = buf; 1947 while ((p = strsep(&next, "\n\r"))) { 1948 printf("%d%s %s\r\n", n, (next != '\0') ? "-" : "", p); 1949 if (debug) 1950 syslog(LOG_DEBUG, "<--- %d%s %s", n, 1951 (next != '\0') ? "-" : "", p); 1952 } 1953 (void)fflush(stdout); 1954 free(buf); 1955} 1956 1957 1958void 1959reply_r(int n, const char *fmt, ...) 1960{ 1961 char *p, *next; 1962 char msg[BUFSIZ]; 1963 char buf[BUFSIZ]; 1964 va_list ap; 1965 struct syslog_data sdata = SYSLOG_DATA_INIT; 1966 1967 sdata.log_fac = LOG_FTP; 1968 va_start(ap, fmt); 1969 vsnprintf(msg, sizeof(msg), fmt, ap); 1970 va_end(ap); 1971 1972 next = msg; 1973 1974 while ((p = strsep(&next, "\n\r"))) { 1975 snprintf(buf, sizeof(buf), "%d%s %s\r\n", n, 1976 (next != '\0') ? "-" : "", p); 1977 write(STDOUT_FILENO, buf, strlen(buf)); 1978 if (debug) { 1979 buf[strlen(buf) - 2] = '\0'; 1980 syslog_r(LOG_DEBUG, &sdata, "<--- %s", buf); 1981 } 1982 } 1983} 1984 1985void 1986lreply(int n, const char *fmt, ...) 1987{ 1988 va_list ap; 1989 1990 va_start(ap, fmt); 1991 (void)printf("%d- ", n); 1992 (void)vprintf(fmt, ap); 1993 va_end(ap); 1994 (void)printf("\r\n"); 1995 (void)fflush(stdout); 1996 if (debug) { 1997 va_start(ap, fmt); 1998 syslog(LOG_DEBUG, "<--- %d- ", n); 1999 vsyslog(LOG_DEBUG, fmt, ap); 2000 va_end(ap); 2001 } 2002} 2003 2004static void 2005ack(char *s) 2006{ 2007 2008 reply(250, "%s command successful.", s); 2009} 2010 2011void 2012nack(char *s) 2013{ 2014 2015 reply(502, "%s command not implemented.", s); 2016} 2017 2018/* ARGSUSED */ 2019void 2020yyerror(char *s) 2021{ 2022 cbuf[strcspn(cbuf, "\n")] = '\0'; 2023 reply(500, "'%s': command not understood.", cbuf); 2024} 2025 2026void 2027delete(char *name) 2028{ 2029 struct stat st; 2030 2031 LOGCMD("delete", name); 2032 if (stat(name, &st) < 0) { 2033 perror_reply(550, name); 2034 return; 2035 } 2036 if ((st.st_mode&S_IFMT) == S_IFDIR) { 2037 if (rmdir(name) < 0) { 2038 perror_reply(550, name); 2039 return; 2040 } 2041 goto done; 2042 } 2043 if (unlink(name) < 0) { 2044 perror_reply(550, name); 2045 return; 2046 } 2047done: 2048 ack("DELE"); 2049} 2050 2051void 2052cwd(char *path) 2053{ 2054 FILE *message; 2055 2056 if (chdir(path) < 0) 2057 perror_reply(550, path); 2058 else { 2059 if ((message = fopen(_PATH_CWDMESG, "r")) != NULL) { 2060 char line[LINE_MAX]; 2061 2062 while (fgets(line, sizeof(line), message) != NULL) { 2063 line[strcspn(line, "\n")] = '\0'; 2064 lreply(250, "%s", line); 2065 } 2066 (void) fflush(stdout); 2067 (void) fclose(message); 2068 } 2069 ack("CWD"); 2070 } 2071} 2072 2073void 2074replydirname(const char *name, const char *message) 2075{ 2076 char *p, *ep; 2077 char npath[MAXPATHLEN * 2]; 2078 2079 p = npath; 2080 ep = &npath[sizeof(npath) - 1]; 2081 while (*name) { 2082 if (*name == '"') { 2083 if (ep - p < 2) 2084 break; 2085 *p++ = *name++; 2086 *p++ = '"'; 2087 } else { 2088 if (ep - p < 1) 2089 break; 2090 *p++ = *name++; 2091 } 2092 } 2093 *p = '\0'; 2094 reply(257, "\"%s\" %s", npath, message); 2095} 2096 2097void 2098makedir(char *name) 2099{ 2100 2101 LOGCMD("mkdir", name); 2102 if (mkdir(name, 0777) < 0) 2103 perror_reply(550, name); 2104 else 2105 replydirname(name, "directory created."); 2106} 2107 2108void 2109removedir(char *name) 2110{ 2111 2112 LOGCMD("rmdir", name); 2113 if (rmdir(name) < 0) 2114 perror_reply(550, name); 2115 else 2116 ack("RMD"); 2117} 2118 2119void 2120pwd(void) 2121{ 2122 char path[MAXPATHLEN]; 2123 2124 if (getcwd(path, sizeof(path)) == NULL) 2125 perror_reply(550, "Can't get current directory"); 2126 else 2127 replydirname(path, "is current directory."); 2128} 2129 2130char * 2131renamefrom(char *name) 2132{ 2133 struct stat st; 2134 2135 if (stat(name, &st) < 0) { 2136 perror_reply(550, name); 2137 return ((char *)0); 2138 } 2139 reply(350, "File exists, ready for destination name"); 2140 return (name); 2141} 2142 2143void 2144renamecmd(char *from, char *to) 2145{ 2146 2147 LOGCMD2("rename", from, to); 2148 if (rename(from, to) < 0) 2149 perror_reply(550, "rename"); 2150 else 2151 ack("RNTO"); 2152} 2153 2154static void 2155dolog(struct sockaddr *sa) 2156{ 2157 char hbuf[sizeof(remotehost)]; 2158 2159 if (getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), NULL, 0, 0) == 0) 2160 (void) strlcpy(remotehost, hbuf, sizeof(remotehost)); 2161 else 2162 (void) strlcpy(remotehost, "unknown", sizeof(remotehost)); 2163 2164#ifdef HASSETPROCTITLE 2165 snprintf(proctitle, sizeof(proctitle), "%s: connected", remotehost); 2166 setproctitle("%s", proctitle); 2167#endif /* HASSETPROCTITLE */ 2168 2169 if (logging) { 2170 int error; 2171 error = getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), 2172 NULL, 0, NI_NUMERICHOST); 2173 syslog(LOG_INFO, "connection from %s [%s]", remotehost, 2174 error ? gai_strerror(error) : hbuf); 2175 } 2176} 2177 2178/* 2179 * Record logout in wtmp file and exit with supplied status. 2180 * NOTE: because this is called from signal handlers it cannot 2181 * use stdio (or call other functions that use stdio). 2182 */ 2183void 2184dologout(int status) 2185{ 2186 2187 transflag = 0; 2188 2189 if (logged_in) { 2190 sigprocmask(SIG_BLOCK, &allsigs, NULL); 2191 ftpdlogwtmp(ttyline, "", ""); 2192 if (doutmp) 2193 ftpd_logout(utmp.ut_line); 2194 } 2195 /* beware of flushing buffers after a SIGPIPE */ 2196 _exit(status); 2197} 2198 2199/*ARGSUSED*/ 2200static void 2201sigurg(int signo) 2202{ 2203 2204 recvurg = 1; 2205} 2206 2207static void 2208myoob(void) 2209{ 2210 char *cp; 2211 int ret; 2212 2213 /* only process if transfer occurring */ 2214 if (!transflag) 2215 return; 2216 cp = tmpline; 2217 ret = getline(cp, 7, stdin); 2218 if (ret == -1) { 2219 reply(221, "You could at least say goodbye."); 2220 dologout(0); 2221 } else if (ret == -2) { 2222 /* Ignore truncated command */ 2223 return; 2224 } 2225 upper(cp); 2226 if (strcmp(cp, "ABOR\r\n") == 0) { 2227 tmpline[0] = '\0'; 2228 reply(426, "Transfer aborted. Data connection closed."); 2229 reply(226, "Abort successful"); 2230 } 2231 if (strcmp(cp, "STAT\r\n") == 0) { 2232 tmpline[0] = '\0'; 2233 if (file_size != (off_t) -1) 2234 reply(213, "Status: %qd of %qd bytes transferred", 2235 byte_count, file_size); 2236 else 2237 reply(213, "Status: %qd bytes transferred", byte_count); 2238 } 2239} 2240 2241/* 2242 * Note: a response of 425 is not mentioned as a possible response to 2243 * the PASV command in RFC959. However, it has been blessed as 2244 * a legitimate response by Jon Postel in a telephone conversation 2245 * with Rick Adams on 25 Jan 89. 2246 */ 2247void 2248passive(void) 2249{ 2250 socklen_t len; 2251 int on; 2252 u_char *p, *a; 2253 2254 if (pw == NULL) { 2255 reply(530, "Please login with USER and PASS"); 2256 return; 2257 } 2258 if (pdata >= 0) 2259 close(pdata); 2260 /* 2261 * XXX 2262 * At this point, it would be nice to have an algorithm that 2263 * inserted a growing delay in an attack scenario. Such a thing 2264 * would look like continual passive sockets being opened, but 2265 * nothing serious being done with them. They're not used to 2266 * move data; the entire attempt is just to use tcp FIN_WAIT 2267 * resources. 2268 */ 2269 pdata = socket(AF_INET, SOCK_STREAM, 0); 2270 if (pdata < 0) { 2271 perror_reply(425, "Can't open passive connection"); 2272 return; 2273 } 2274 2275 on = IP_PORTRANGE_HIGH; 2276 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2277 &on, sizeof(on)) < 0) 2278 goto pasv_error; 2279 2280 pasv_addr = ctrl_addr; 2281 pasv_addr.su_sin.sin_port = 0; 2282 if (bind(pdata, (struct sockaddr *)&pasv_addr, 2283 pasv_addr.su_len) < 0) 2284 goto pasv_error; 2285 2286 len = sizeof(pasv_addr); 2287 if (getsockname(pdata, (struct sockaddr *)&pasv_addr, &len) < 0) 2288 goto pasv_error; 2289 if (listen(pdata, 1) < 0) 2290 goto pasv_error; 2291 a = (u_char *)&pasv_addr.su_sin.sin_addr; 2292 p = (u_char *)&pasv_addr.su_sin.sin_port; 2293 2294 reply(227, "Entering Passive Mode (%u,%u,%u,%u,%u,%u)", a[0], 2295 a[1], a[2], a[3], p[0], p[1]); 2296 return; 2297 2298pasv_error: 2299 perror_reply(425, "Can't open passive connection"); 2300 (void) close(pdata); 2301 pdata = -1; 2302 return; 2303} 2304 2305int 2306epsvproto2af(int proto) 2307{ 2308 2309 switch (proto) { 2310 case 1: return AF_INET; 2311#ifdef INET6 2312 case 2: return AF_INET6; 2313#endif 2314 default: return -1; 2315 } 2316} 2317 2318int 2319af2epsvproto(int af) 2320{ 2321 2322 switch (af) { 2323 case AF_INET: return 1; 2324#ifdef INET6 2325 case AF_INET6: return 2; 2326#endif 2327 default: return -1; 2328 } 2329} 2330 2331/* 2332 * 228 Entering Long Passive Mode (af, hal, h1, h2, h3,..., pal, p1, p2...) 2333 * 229 Entering Extended Passive Mode (|||port|) 2334 */ 2335void 2336long_passive(char *cmd, int pf) 2337{ 2338 socklen_t len; 2339 int on; 2340 u_char *p, *a; 2341 2342 if (!logged_in) { 2343 syslog(LOG_NOTICE, "long passive but not logged in"); 2344 reply(503, "Login with USER first."); 2345 return; 2346 } 2347 2348 if (pf != PF_UNSPEC && ctrl_addr.su_family != pf) { 2349 /* 2350 * XXX 2351 * only EPRT/EPSV ready clients will understand this 2352 */ 2353 if (strcmp(cmd, "EPSV") != 0) 2354 reply(501, "Network protocol mismatch"); /*XXX*/ 2355 else 2356 epsv_protounsupp("Network protocol mismatch"); 2357 2358 return; 2359 } 2360 2361 if (pdata >= 0) 2362 close(pdata); 2363 /* 2364 * XXX 2365 * At this point, it would be nice to have an algorithm that 2366 * inserted a growing delay in an attack scenario. Such a thing 2367 * would look like continual passive sockets being opened, but 2368 * nothing serious being done with them. They not used to move 2369 * data; the entire attempt is just to use tcp FIN_WAIT 2370 * resources. 2371 */ 2372 pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 2373 if (pdata < 0) { 2374 perror_reply(425, "Can't open passive connection"); 2375 return; 2376 } 2377 2378 switch (ctrl_addr.su_family) { 2379 case AF_INET: 2380 on = IP_PORTRANGE_HIGH; 2381 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2382 &on, sizeof(on)) < 0) 2383 goto pasv_error; 2384 break; 2385 case AF_INET6: 2386 on = IPV6_PORTRANGE_HIGH; 2387 if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE, 2388 &on, sizeof(on)) < 0) 2389 goto pasv_error; 2390 break; 2391 } 2392 2393 pasv_addr = ctrl_addr; 2394 pasv_addr.su_port = 0; 2395 if (bind(pdata, (struct sockaddr *)&pasv_addr, pasv_addr.su_len) < 0) 2396 goto pasv_error; 2397 len = pasv_addr.su_len; 2398 if (getsockname(pdata, (struct sockaddr *)&pasv_addr, &len) < 0) 2399 goto pasv_error; 2400 if (listen(pdata, 1) < 0) 2401 goto pasv_error; 2402 p = (u_char *)&pasv_addr.su_port; 2403 2404 if (strcmp(cmd, "LPSV") == 0) { 2405 switch (pasv_addr.su_family) { 2406 case AF_INET: 2407 a = (u_char *)&pasv_addr.su_sin.sin_addr; 2408 reply(228, 2409 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2410 4, 4, a[0], a[1], a[2], a[3], 2, p[0], p[1]); 2411 return; 2412 case AF_INET6: 2413 a = (u_char *)&pasv_addr.su_sin6.sin6_addr; 2414 reply(228, 2415 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u," 2416 "%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2417 6, 16, a[0], a[1], a[2], a[3], a[4], 2418 a[5], a[6], a[7], a[8], a[9], a[10], 2419 a[11], a[12], a[13], a[14], a[15], 2420 2, p[0], p[1]); 2421 return; 2422 } 2423 } else if (strcmp(cmd, "EPSV") == 0) { 2424 switch (pasv_addr.su_family) { 2425 case AF_INET: 2426 case AF_INET6: 2427 reply(229, "Entering Extended Passive Mode (|||%u|)", 2428 ntohs(pasv_addr.su_port)); 2429 return; 2430 } 2431 } else { 2432 /* more proper error code? */ 2433 } 2434 2435 pasv_error: 2436 perror_reply(425, "Can't open passive connection"); 2437 (void) close(pdata); 2438 pdata = -1; 2439 return; 2440} 2441 2442/* 2443 * EPRT |proto|addr|port| 2444 */ 2445int 2446extended_port(const char *arg) 2447{ 2448 char *tmp = NULL; 2449 char *result[3]; 2450 char *p, *q; 2451 char delim; 2452 struct addrinfo hints; 2453 struct addrinfo *res = NULL; 2454 int i; 2455 unsigned long proto; 2456 2457 if (epsvall) { 2458 reply(501, "EPRT disallowed after EPSV ALL"); 2459 return -1; 2460 } 2461 2462 usedefault = 0; 2463 if (pdata >= 0) { 2464 (void) close(pdata); 2465 pdata = -1; 2466 } 2467 2468 tmp = strdup(arg); 2469 if (!tmp) { 2470 fatal("not enough core."); 2471 /*NOTREACHED*/ 2472 } 2473 p = tmp; 2474 delim = p[0]; 2475 p++; 2476 memset(result, 0, sizeof(result)); 2477 for (i = 0; i < 3; i++) { 2478 q = strchr(p, delim); 2479 if (!q || *q != delim) 2480 goto parsefail; 2481 *q++ = '\0'; 2482 result[i] = p; 2483 p = q; 2484 } 2485 2486 /* some more sanity check */ 2487 p = NULL; 2488 (void)strtoul(result[2], &p, 10); 2489 if (!*result[2] || *p) 2490 goto protounsupp; 2491 p = NULL; 2492 proto = strtoul(result[0], &p, 10); 2493 if (!*result[0] || *p) 2494 goto protounsupp; 2495 2496 memset(&hints, 0, sizeof(hints)); 2497 hints.ai_family = epsvproto2af((int)proto); 2498 if (hints.ai_family < 0) 2499 goto protounsupp; 2500 hints.ai_socktype = SOCK_STREAM; 2501 hints.ai_flags = AI_NUMERICHOST; /*no DNS*/ 2502 if (getaddrinfo(result[1], result[2], &hints, &res)) 2503 goto parsefail; 2504 if (res->ai_next) 2505 goto parsefail; 2506 if (sizeof(data_dest) < res->ai_addrlen) 2507 goto parsefail; 2508 memcpy(&data_dest, res->ai_addr, res->ai_addrlen); 2509 if (his_addr.su_family == AF_INET6 && 2510 data_dest.su_family == AF_INET6) { 2511 /* XXX more sanity checks! */ 2512 data_dest.su_sin6.sin6_scope_id = 2513 his_addr.su_sin6.sin6_scope_id; 2514 } 2515 if (pdata >= 0) { 2516 (void) close(pdata); 2517 pdata = -1; 2518 } 2519 reply(200, "EPRT command successful."); 2520 2521 if (tmp) 2522 free(tmp); 2523 if (res) 2524 freeaddrinfo(res); 2525 return 0; 2526 2527parsefail: 2528 reply(500, "Invalid argument, rejected."); 2529 usedefault = 1; 2530 if (tmp) 2531 free(tmp); 2532 if (res) 2533 freeaddrinfo(res); 2534 return -1; 2535 2536protounsupp: 2537 epsv_protounsupp("Protocol not supported"); 2538 usedefault = 1; 2539 if (tmp) 2540 free(tmp); 2541 if (res) 2542 freeaddrinfo(res); 2543 return -1; 2544} 2545 2546/* 2547 * 522 Protocol not supported (proto,...) 2548 * as we assume address family for control and data connections are the same, 2549 * we do not return the list of address families we support - instead, we 2550 * return the address family of the control connection. 2551 */ 2552void 2553epsv_protounsupp(const char *message) 2554{ 2555 int proto; 2556 2557 proto = af2epsvproto(ctrl_addr.su_family); 2558 if (proto < 0) 2559 reply(501, "%s", message); /*XXX*/ 2560 else 2561 reply(522, "%s, use (%d)", message, proto); 2562} 2563 2564/* 2565 * Generate unique name for file with basename "local". 2566 * The file named "local" is already known to exist. 2567 * Generates failure reply on error. 2568 */ 2569static int 2570guniquefd(char *local, char **nam) 2571{ 2572 static char new[MAXPATHLEN]; 2573 struct stat st; 2574 int count, len, fd; 2575 char *cp; 2576 2577 cp = strrchr(local, '/'); 2578 if (cp) 2579 *cp = '\0'; 2580 if (stat(cp ? local : ".", &st) < 0) { 2581 perror_reply(553, cp ? local : "."); 2582 return (-1); 2583 } 2584 if (cp) 2585 *cp = '/'; 2586 len = strlcpy(new, local, sizeof(new)); 2587 if (len+2+1 >= sizeof(new)-1) 2588 return (-1); 2589 cp = new + len; 2590 *cp++ = '.'; 2591 for (count = 1; count < 100; count++) { 2592 (void)snprintf(cp, sizeof(new) - (cp - new), "%d", count); 2593 fd = open(new, O_RDWR|O_CREAT|O_EXCL, 0666); 2594 if (fd == -1) 2595 continue; 2596 if (nam) 2597 *nam = new; 2598 return (fd); 2599 } 2600 reply(452, "Unique file name cannot be created."); 2601 return (-1); 2602} 2603 2604/* 2605 * Format and send reply containing system error number. 2606 */ 2607void 2608perror_reply(int code, char *string) 2609{ 2610 2611 reply(code, "%s: %s.", string, strerror(errno)); 2612} 2613 2614static char *onefile[] = { 2615 "", 2616 0 2617}; 2618 2619void 2620send_file_list(char *whichf) 2621{ 2622 struct stat st; 2623 DIR *dirp = NULL; 2624 struct dirent *dir; 2625 FILE *dout = NULL; 2626 char **dirlist; 2627 char *dirname; 2628 int simple = 0; 2629 volatile int freeglob = 0; 2630 glob_t gl; 2631 2632 if (strpbrk(whichf, "~{[*?") != NULL) { 2633 memset(&gl, 0, sizeof(gl)); 2634 freeglob = 1; 2635 if (glob(whichf, 2636 GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE|GLOB_LIMIT, 2637 0, &gl)) { 2638 reply(550, "not found"); 2639 goto out; 2640 } else if (gl.gl_pathc == 0) { 2641 errno = ENOENT; 2642 perror_reply(550, whichf); 2643 goto out; 2644 } 2645 dirlist = gl.gl_pathv; 2646 } else { 2647 onefile[0] = whichf; 2648 dirlist = onefile; 2649 simple = 1; 2650 } 2651 2652 while ((dirname = *dirlist++)) { 2653 if (stat(dirname, &st) < 0) { 2654 /* 2655 * If user typed "ls -l", etc, and the client 2656 * used NLST, do what the user meant. 2657 */ 2658 if (dirname[0] == '-' && *dirlist == NULL && 2659 transflag == 0) { 2660 retrieve("/bin/ls %s", dirname); 2661 goto out; 2662 } 2663 perror_reply(550, whichf); 2664 if (dout != NULL) { 2665 (void) fclose(dout); 2666 transflag = 0; 2667 data = -1; 2668 pdata = -1; 2669 } 2670 goto out; 2671 } 2672 2673 if (S_ISREG(st.st_mode)) { 2674 if (dout == NULL) { 2675 dout = dataconn("file list", (off_t)-1, "w"); 2676 if (dout == NULL) 2677 goto out; 2678 transflag++; 2679 } 2680 fprintf(dout, "%s%s\n", dirname, 2681 type == TYPE_A ? "\r" : ""); 2682 byte_count += strlen(dirname) + 1; 2683 continue; 2684 } else if (!S_ISDIR(st.st_mode)) 2685 continue; 2686 2687 if ((dirp = opendir(dirname)) == NULL) 2688 continue; 2689 2690 while ((dir = readdir(dirp)) != NULL) { 2691 char nbuf[MAXPATHLEN]; 2692 2693 if (recvurg) { 2694 myoob(); 2695 recvurg = 0; 2696 transflag = 0; 2697 goto out; 2698 } 2699 2700 if (dir->d_name[0] == '.' && dir->d_namlen == 1) 2701 continue; 2702 if (dir->d_name[0] == '.' && dir->d_name[1] == '.' && 2703 dir->d_namlen == 2) 2704 continue; 2705 2706 snprintf(nbuf, sizeof(nbuf), "%s/%s", dirname, 2707 dir->d_name); 2708 2709 /* 2710 * We have to do a stat to insure it's 2711 * not a directory or special file. 2712 */ 2713 if (simple || (stat(nbuf, &st) == 0 && 2714 S_ISREG(st.st_mode))) { 2715 if (dout == NULL) { 2716 dout = dataconn("file list", (off_t)-1, 2717 "w"); 2718 if (dout == NULL) 2719 goto out; 2720 transflag++; 2721 } 2722 if (nbuf[0] == '.' && nbuf[1] == '/') 2723 fprintf(dout, "%s%s\n", &nbuf[2], 2724 type == TYPE_A ? "\r" : ""); 2725 else 2726 fprintf(dout, "%s%s\n", nbuf, 2727 type == TYPE_A ? "\r" : ""); 2728 byte_count += strlen(nbuf) + 1; 2729 } 2730 } 2731 (void) closedir(dirp); 2732 } 2733 2734 if (dout == NULL) 2735 reply(550, "No files found."); 2736 else if (ferror(dout) != 0) 2737 perror_reply(550, "Data connection"); 2738 else 2739 reply(226, "Transfer complete."); 2740 2741 transflag = 0; 2742 if (dout != NULL) 2743 (void) fclose(dout); 2744 else { 2745 if (pdata >= 0) 2746 close(pdata); 2747 } 2748 data = -1; 2749 pdata = -1; 2750out: 2751 if (freeglob) { 2752 freeglob = 0; 2753 globfree(&gl); 2754 } 2755} 2756 2757/*ARGSUSED*/ 2758static void 2759reapchild(int signo) 2760{ 2761 int save_errno = errno; 2762 int rval; 2763 2764 do { 2765 rval = waitpid(-1, NULL, WNOHANG); 2766 } while (rval > 0 || (rval == -1 && errno == EINTR)); 2767 errno = save_errno; 2768} 2769 2770void 2771logxfer(char *name, off_t size, time_t start) 2772{ 2773 char buf[400 + MAXHOSTNAMELEN*4 + MAXPATHLEN*4]; 2774 char dir[MAXPATHLEN], path[MAXPATHLEN], rpath[MAXPATHLEN]; 2775 char vremotehost[MAXHOSTNAMELEN*4], vpath[MAXPATHLEN*4]; 2776 char *vpw; 2777 time_t now; 2778 int len; 2779 2780 if ((statfd >= 0) && (getcwd(dir, sizeof(dir)) != NULL)) { 2781 time(&now); 2782 2783 vpw = malloc(strlen(guest ? guestpw : pw->pw_name) * 4 + 1); 2784 if (vpw == NULL) 2785 return; 2786 2787 snprintf(path, sizeof(path), "%s/%s", dir, name); 2788 if (realpath(path, rpath) == NULL) 2789 strlcpy(rpath, path, sizeof(rpath)); 2790 strvis(vpath, rpath, VIS_SAFE|VIS_NOSLASH); 2791 2792 strvis(vremotehost, remotehost, VIS_SAFE|VIS_NOSLASH); 2793 strvis(vpw, guest? guestpw : pw->pw_name, VIS_SAFE|VIS_NOSLASH); 2794 2795 len = snprintf(buf, sizeof(buf), 2796 "%.24s %d %s %qd %s %c %s %c %c %s ftp %d %s %s\n", 2797 ctime(&now), now - start + (now == start), 2798 vremotehost, (long long)size, vpath, 2799 ((type == TYPE_A) ? 'a' : 'b'), "*" /* none yet */, 2800 'o', ((guest) ? 'a' : 'r'), 2801 vpw, 0 /* none yet */, 2802 ((guest) ? "*" : pw->pw_name), dhostname); 2803 free(vpw); 2804 2805 if (len >= sizeof(buf) || len == -1) { 2806 if ((len = strlen(buf)) == 0) 2807 return; /* should not happen */ 2808 buf[len - 1] = '\n'; 2809 } 2810 write(statfd, buf, len); 2811 } 2812} 2813 2814void 2815set_slave_signals(void) 2816{ 2817 struct sigaction sa; 2818 2819 sigemptyset(&sa.sa_mask); 2820 sa.sa_flags = SA_RESTART; 2821 2822 sa.sa_handler = SIG_DFL; 2823 (void) sigaction(SIGCHLD, &sa, NULL); 2824 2825 sa.sa_handler = sigurg; 2826 sa.sa_flags = 0; /* don't restart syscalls for SIGURG */ 2827 (void) sigaction(SIGURG, &sa, NULL); 2828 2829 sigfillset(&sa.sa_mask); /* block all signals in handler */ 2830 sa.sa_flags = SA_RESTART; 2831 sa.sa_handler = sigquit; 2832 (void) sigaction(SIGHUP, &sa, NULL); 2833 (void) sigaction(SIGINT, &sa, NULL); 2834 (void) sigaction(SIGQUIT, &sa, NULL); 2835 (void) sigaction(SIGTERM, &sa, NULL); 2836 2837 sa.sa_handler = lostconn; 2838 (void) sigaction(SIGPIPE, &sa, NULL); 2839 2840 sa.sa_handler = toolong; 2841 (void) sigaction(SIGALRM, &sa, NULL); 2842 2843#ifdef F_SETOWN 2844 if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1) 2845 syslog(LOG_ERR, "fcntl F_SETOWN: %m"); 2846#endif 2847} 2848 2849#if defined(TCPWRAPPERS) 2850static int 2851check_host(struct sockaddr *sa) 2852{ 2853 struct sockaddr_in *sin; 2854 struct hostent *hp; 2855 char *addr; 2856 2857 if (sa->sa_family != AF_INET) 2858 return 1; /*XXX*/ 2859 2860 sin = (struct sockaddr_in *)sa; 2861 hp = gethostbyaddr((char *)&sin->sin_addr, 2862 sizeof(struct in_addr), AF_INET); 2863 addr = inet_ntoa(sin->sin_addr); 2864 if (hp) { 2865 if (!hosts_ctl("ftpd", hp->h_name, addr, STRING_UNKNOWN)) { 2866 syslog(LOG_NOTICE, "tcpwrappers rejected: %s [%s]", 2867 hp->h_name, addr); 2868 return (0); 2869 } 2870 } else { 2871 if (!hosts_ctl("ftpd", STRING_UNKNOWN, addr, STRING_UNKNOWN)) { 2872 syslog(LOG_NOTICE, "tcpwrappers rejected: [%s]", addr); 2873 return (0); 2874 } 2875 } 2876 return (1); 2877} 2878#endif /* TCPWRAPPERS */ 2879 2880/* 2881 * Allocate space and return a copy of the specified dir. 2882 * If 'dir' begins with a tilde (~), expand it. 2883 */ 2884char * 2885copy_dir(char *dir, struct passwd *pw) 2886{ 2887 char *cp; 2888 char *newdir; 2889 char *user = NULL; 2890 2891 /* Nothing to expand */ 2892 if (dir[0] != '~') 2893 return (strdup(dir)); 2894 2895 /* "dir" is of form ~user/some/dir, lookup user. */ 2896 if (dir[1] != '/' && dir[1] != '\0') { 2897 if ((cp = strchr(dir + 1, '/')) == NULL) 2898 cp = dir + strlen(dir); 2899 if ((user = malloc((size_t)(cp - dir))) == NULL) 2900 return (NULL); 2901 strlcpy(user, dir + 1, (size_t)(cp - dir)); 2902 2903 /* Only do lookup if it is a different user. */ 2904 if (strcmp(user, pw->pw_name) != 0) { 2905 if ((pw = getpwnam(user)) == NULL) { 2906 /* No such user, interpret literally */ 2907 free(user); 2908 return(strdup(dir)); 2909 } 2910 } 2911 free(user); 2912 } 2913 2914 /* 2915 * If there is no directory separator (/) then it is just pw_dir. 2916 * Otherwise, replace ~foo with pw_dir. 2917 */ 2918 if ((cp = strchr(dir + 1, '/')) == NULL) { 2919 newdir = strdup(pw->pw_dir); 2920 } else { 2921 if (asprintf(&newdir, "%s%s", pw->pw_dir, cp) == -1) 2922 return (NULL); 2923 } 2924 2925 return(newdir); 2926} 2927