ftpd.c revision 1.206
1/* $OpenBSD: ftpd.c,v 1.206 2015/01/16 06:39:50 deraadt Exp $ */ 2/* $NetBSD: ftpd.c,v 1.15 1995/06/03 22:46:47 mycroft Exp $ */ 3 4/* 5 * Copyright (C) 1997 and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33/* 34 * Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. 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/stat.h> 66#include <sys/ioctl.h> 67#include <sys/socket.h> 68#include <sys/wait.h> 69#include <sys/mman.h> 70 71#include <netinet/in.h> 72#include <netinet/ip.h> 73#include <netinet/tcp.h> 74 75#define FTP_NAMES 76#include <arpa/ftp.h> 77#include <arpa/inet.h> 78#include <arpa/telnet.h> 79 80#include <bsd_auth.h> 81#include <ctype.h> 82#include <dirent.h> 83#include <errno.h> 84#include <fcntl.h> 85#include <glob.h> 86#include <limits.h> 87#include <login_cap.h> 88#include <netdb.h> 89#include <pwd.h> 90#include <signal.h> 91#include <stdarg.h> 92#include <stdio.h> 93#include <stdlib.h> 94#include <string.h> 95#include <syslog.h> 96#include <time.h> 97#include <vis.h> 98#include <unistd.h> 99#include <util.h> 100#include <utmp.h> 101#include <poll.h> 102 103#include "pathnames.h" 104#include "monitor.h" 105#include "extern.h" 106 107extern off_t restart_point; 108extern char cbuf[]; 109 110union sockunion ctrl_addr; 111union sockunion data_source; 112union sockunion data_dest; 113union sockunion his_addr; 114union sockunion pasv_addr; 115 116sigset_t allsigs; 117 118int daemon_mode = 0; 119int data; 120int logged_in; 121struct passwd *pw; 122int debug = 0; 123int timeout = 900; /* timeout after 15 minutes of inactivity */ 124int maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */ 125int logging; 126int anon_ok = 1; 127int anon_only = 0; 128unsigned int minuid = 1000; 129int multihome = 0; 130int guest; 131int stats; 132int statfd = -1; 133int portcheck = 1; 134int dochroot; 135int type; 136int form; 137int stru; /* avoid C keyword */ 138int mode; 139int doutmp = 0; /* update utmp file */ 140int nowtmp = 0; /* do not update wtmp file */ 141int usedefault = 1; /* for data transfers */ 142int pdata = -1; /* for passive mode */ 143int family = AF_UNSPEC; 144volatile sig_atomic_t transflag; 145off_t file_size; 146off_t byte_count; 147#if !defined(CMASK) || CMASK == 0 148#undef CMASK 149#define CMASK 022 150#endif 151mode_t defumask = CMASK; /* default umask value */ 152int umaskchange = 1; /* allow user to change umask value. */ 153char tmpline[7]; 154char hostname[HOST_NAME_MAX+1]; 155char remotehost[HOST_NAME_MAX+1]; 156char dhostname[HOST_NAME_MAX+1]; 157char *guestpw; 158char ttyline[20]; 159#if 0 160char *tty = ttyline; /* for klogin */ 161#endif 162static struct utmp utmp; /* for utmp */ 163static login_cap_t *lc; 164static auth_session_t *as; 165static volatile sig_atomic_t recvurg; 166 167int epsvall = 0; 168 169/* 170 * Timeout intervals for retrying connections 171 * to hosts that don't accept PORT cmds. This 172 * is a kludge, but given the problems with TCP... 173 */ 174#define SWAITMAX 90 /* wait at most 90 seconds */ 175#define SWAITINT 5 /* interval between retries */ 176 177int swaitmax = SWAITMAX; 178int swaitint = SWAITINT; 179 180#ifdef HASSETPROCTITLE 181char proctitle[BUFSIZ]; /* initial part of title */ 182#endif /* HASSETPROCTITLE */ 183 184#define LOGCMD(cmd, file) \ 185 if (logging > 1) \ 186 syslog(LOG_INFO,"%s %s%s", cmd, \ 187 *(file) == '/' ? "" : curdir(), file); 188#define LOGCMD2(cmd, file1, file2) \ 189 if (logging > 1) \ 190 syslog(LOG_INFO,"%s %s%s %s%s", cmd, \ 191 *(file1) == '/' ? "" : curdir(), file1, \ 192 *(file2) == '/' ? "" : curdir(), file2); 193#define LOGBYTES(cmd, file, cnt) \ 194 if (logging > 1) { \ 195 if (cnt == (off_t)-1) \ 196 syslog(LOG_INFO,"%s %s%s", cmd, \ 197 *(file) == '/' ? "" : curdir(), file); \ 198 else \ 199 syslog(LOG_INFO, "%s %s%s = %qd bytes", \ 200 cmd, (*(file) == '/') ? "" : curdir(), file, cnt); \ 201 } 202 203static void ack(char *); 204static void sigurg(int); 205static void myoob(void); 206static int checkuser(char *, char *); 207static FILE *dataconn(char *, off_t, char *); 208static void dolog(struct sockaddr *); 209static char *copy_dir(char *, struct passwd *); 210static char *curdir(void); 211static void end_login(void); 212static FILE *getdatasock(char *); 213static int guniquefd(char *, char **); 214static void lostconn(int); 215static void sigquit(int); 216static int receive_data(FILE *, FILE *); 217static void replydirname(const char *, const char *); 218static int send_data(FILE *, FILE *, off_t, off_t, int); 219static struct passwd * 220 sgetpwnam(char *, struct passwd *); 221static void reapchild(int); 222static void usage(void); 223 224void logxfer(char *, off_t, time_t); 225void set_slave_signals(void); 226 227static char * 228curdir(void) 229{ 230 static char path[PATH_MAX+1]; /* path + '/' */ 231 232 if (getcwd(path, sizeof(path)-1) == NULL) 233 return (""); 234 if (path[1] != '\0') /* special case for root dir. */ 235 strlcat(path, "/", sizeof path); 236 /* For guest account, skip / since it's chrooted */ 237 return (guest ? path+1 : path); 238} 239 240char *argstr = "AdDhnlm:MSt:T:u:PUvW46"; 241 242static void 243usage(void) 244{ 245 syslog(LOG_ERR, 246 "usage: ftpd [-46ADdlMnPSUW] [-m minuid] [-T maxtimeout] " 247 "[-t timeout] [-u mask]"); 248 exit(2); 249} 250 251int 252main(int argc, char *argv[]) 253{ 254 socklen_t addrlen; 255 int ch, on = 1, tos; 256 char line[LINE_MAX]; 257 FILE *fp; 258 struct hostent *hp; 259 struct sigaction sa; 260 int error = 0; 261 const char *errstr; 262 263 tzset(); /* in case no timezone database in ~ftp */ 264 sigfillset(&allsigs); /* used to block signals while root */ 265 sigemptyset(&sa.sa_mask); 266 sa.sa_flags = SA_RESTART; 267 268 while ((ch = getopt(argc, argv, argstr)) != -1) { 269 switch (ch) { 270 case 'A': 271 anon_only = 1; 272 break; 273 274 case 'd': 275 case 'v': /* deprecated */ 276 debug = 1; 277 break; 278 279 case 'D': 280 daemon_mode = 1; 281 break; 282 283 case 'P': 284 portcheck = 0; 285 break; 286 287 case 'h': /* deprecated */ 288 break; 289 290 case 'l': 291 logging++; /* > 1 == extra logging */ 292 break; 293 294 case 'm': 295 minuid = strtonum(optarg, 0, UINT_MAX, &errstr); 296 if (errstr) { 297 syslog(LOG_ERR, 298 "%s is a bad value for -m, aborting", 299 optarg); 300 exit(2); 301 } 302 break; 303 304 case 'M': 305 multihome = 1; 306 break; 307 308 case 'n': 309 anon_ok = 0; 310 break; 311 312 case 'S': 313 stats = 1; 314 break; 315 316 case 't': 317 timeout = strtonum(optarg, 0, INT_MAX, &errstr); 318 if (errstr) { 319 syslog(LOG_ERR, 320 "%s is a bad value for -t, aborting", 321 optarg); 322 exit(2); 323 } 324 if (maxtimeout < timeout) 325 maxtimeout = timeout; 326 break; 327 328 case 'T': 329 maxtimeout = strtonum(optarg, 0, INT_MAX, 330 &errstr); 331 if (errstr) { 332 syslog(LOG_ERR, 333 "%s is a bad value for -T, aborting", 334 optarg); 335 exit(2); 336 } 337 if (timeout > maxtimeout) 338 timeout = maxtimeout; 339 break; 340 341 case 'u': 342 { 343 long val = 0; 344 char *p; 345 umaskchange = 0; 346 347 val = strtol(optarg, &p, 8); 348 if (*optarg == '\0' || *p != '\0' || val < 0 || 349 (val & ~ACCESSPERMS)) { 350 syslog(LOG_ERR, 351 "%s is a bad value for -u, aborting", 352 optarg); 353 exit(2); 354 } 355 defumask = val; 356 break; 357 } 358 359 case 'U': 360 doutmp = 1; 361 break; 362 363 case 'W': 364 nowtmp = 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 if (nowtmp && doutmp) { 382 syslog(LOG_ERR, "options 'U' and 'W' are mutually exclusive"); 383 exit(1); 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 (getpwnam(FTPD_PRIVSEP_USER) == NULL) { 395 syslog(LOG_ERR, "privilege separation user %s not found", 396 FTPD_PRIVSEP_USER); 397 exit(1); 398 } 399 endpwent(); 400 401 if (daemon_mode) { 402 int *fds, i, fd; 403 struct pollfd *pfds; 404 struct addrinfo hints, *res, *res0; 405 nfds_t n; 406 407 /* 408 * Detach from parent. 409 */ 410 if (daemon(1, 1) < 0) { 411 syslog(LOG_ERR, "failed to become a daemon"); 412 exit(1); 413 } 414 sa.sa_handler = reapchild; 415 (void) sigaction(SIGCHLD, &sa, NULL); 416 417 memset(&hints, 0, sizeof(hints)); 418 hints.ai_family = family; 419 hints.ai_socktype = SOCK_STREAM; 420 hints.ai_protocol = IPPROTO_TCP; 421 hints.ai_flags = AI_PASSIVE; 422 error = getaddrinfo(NULL, "ftp", &hints, &res0); 423 if (error) { 424 syslog(LOG_ERR, "%s", gai_strerror(error)); 425 exit(1); 426 } 427 428 n = 0; 429 for (res = res0; res; res = res->ai_next) 430 n++; 431 432 fds = calloc(n, sizeof(int)); 433 pfds = calloc(n, sizeof(struct pollfd)); 434 if (!fds || !pfds) { 435 syslog(LOG_ERR, "%s", strerror(errno)); 436 exit(1); 437 } 438 439 /* 440 * Open sockets, bind it to the FTP port, and start 441 * listening. 442 */ 443 n = 0; 444 for (res = res0; res; res = res->ai_next) { 445 fds[n] = socket(res->ai_family, res->ai_socktype, 446 res->ai_protocol); 447 if (fds[n] < 0) 448 continue; 449 450 if (setsockopt(fds[n], SOL_SOCKET, SO_KEEPALIVE, 451 &on, sizeof(on)) < 0) { 452 close(fds[n]); 453 fds[n] = -1; 454 continue; 455 } 456 457 if (setsockopt(fds[n], SOL_SOCKET, SO_REUSEADDR, 458 &on, sizeof(on)) < 0) { 459 close(fds[n]); 460 fds[n] = -1; 461 continue; 462 } 463 464 if (bind(fds[n], res->ai_addr, res->ai_addrlen) < 0) { 465 close(fds[n]); 466 fds[n] = -1; 467 continue; 468 } 469 if (listen(fds[n], 32) < 0) { 470 close(fds[n]); 471 fds[n] = -1; 472 continue; 473 } 474 475 pfds[n].fd = fds[n]; 476 pfds[n].events = POLLIN; 477 n++; 478 } 479 freeaddrinfo(res0); 480 481 if (n == 0) { 482 syslog(LOG_ERR, "could not open control socket"); 483 exit(1); 484 } 485 486 /* Stash pid in pidfile */ 487 if (pidfile(NULL)) 488 syslog(LOG_ERR, "can't open pidfile: %m"); 489 /* 490 * Loop forever accepting connection requests and forking off 491 * children to handle them. 492 */ 493 while (1) { 494 if (poll(pfds, n, INFTIM) < 0) { 495 if (errno == EINTR) 496 continue; 497 syslog(LOG_ERR, "poll: %m"); 498 exit(1); 499 } 500 for (i = 0; i < n; i++) 501 if (pfds[i].revents & POLLIN) { 502 addrlen = sizeof(his_addr); 503 fd = accept(pfds[i].fd, 504 (struct sockaddr *)&his_addr, 505 &addrlen); 506 if (fd != -1) { 507 if (fork() == 0) 508 goto child; 509 close(fd); 510 } 511 } 512 } 513 514 child: 515 /* child */ 516 (void)dup2(fd, STDIN_FILENO); 517 (void)dup2(fd, STDOUT_FILENO); 518 for (i = 0; i < n; i++) 519 close(fds[i]); 520 } else { 521 addrlen = sizeof(his_addr); 522 if (getpeername(0, (struct sockaddr *)&his_addr, 523 &addrlen) < 0) { 524 /* syslog(LOG_ERR, "getpeername (%s): %m", argv[0]); */ 525 exit(1); 526 } 527 } 528 529 /* set this here so klogin can use it... */ 530 (void)snprintf(ttyline, sizeof(ttyline), "ftp%ld", (long)getpid()); 531 532 set_slave_signals(); 533 534 addrlen = sizeof(ctrl_addr); 535 if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) { 536 syslog(LOG_ERR, "getsockname: %m"); 537 exit(1); 538 } 539 if (his_addr.su_family == AF_INET6 && 540 IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr)) { 541#if 1 542 /* 543 * IPv4 control connection arrived to AF_INET6 socket. 544 * I hate to do this, but this is the easiest solution. 545 */ 546 union sockunion tmp_addr; 547 const int off = sizeof(struct in6_addr) - sizeof(struct in_addr); 548 549 tmp_addr = his_addr; 550 memset(&his_addr, 0, sizeof(his_addr)); 551 his_addr.su_sin.sin_family = AF_INET; 552 his_addr.su_sin.sin_len = sizeof(his_addr.su_sin); 553 memcpy(&his_addr.su_sin.sin_addr, 554 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 555 sizeof(his_addr.su_sin.sin_addr)); 556 his_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 557 558 tmp_addr = ctrl_addr; 559 memset(&ctrl_addr, 0, sizeof(ctrl_addr)); 560 ctrl_addr.su_sin.sin_family = AF_INET; 561 ctrl_addr.su_sin.sin_len = sizeof(ctrl_addr.su_sin); 562 memcpy(&ctrl_addr.su_sin.sin_addr, 563 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 564 sizeof(ctrl_addr.su_sin.sin_addr)); 565 ctrl_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 566#else 567 while (fgets(line, sizeof(line), fd) != NULL) { 568 line[strcspn(line, "\n")] = '\0'; 569 lreply(530, "%s", line); 570 } 571 (void) fflush(stdout); 572 (void) close(fd); 573 reply(530, 574 "Connection from IPv4 mapped address is not supported."); 575 exit(0); 576#endif 577 } 578#ifdef IP_TOS 579 if (his_addr.su_family == AF_INET) { 580 tos = IPTOS_LOWDELAY; 581 if (setsockopt(0, IPPROTO_IP, IP_TOS, &tos, 582 sizeof(int)) < 0) 583 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 584 } 585#endif 586 data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1); 587 588 /* Try to handle urgent data inline */ 589#ifdef SO_OOBINLINE 590 if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, &on, sizeof(on)) < 0) 591 syslog(LOG_ERR, "setsockopt: %m"); 592#endif 593 594 dolog((struct sockaddr *)&his_addr); 595 596 /* 597 * Set up default state 598 */ 599 data = -1; 600 type = TYPE_A; 601 form = FORM_N; 602 stru = STRU_F; 603 mode = MODE_S; 604 tmpline[0] = '\0'; 605 606 /* If logins are disabled, print out the message. */ 607 if ((fp = fopen(_PATH_NOLOGIN, "r")) != NULL) { 608 while (fgets(line, sizeof(line), fp) != NULL) { 609 line[strcspn(line, "\n")] = '\0'; 610 lreply(530, "%s", line); 611 } 612 (void) fflush(stdout); 613 (void) fclose(fp); 614 reply(530, "System not available."); 615 exit(0); 616 } 617 if ((fp = fopen(_PATH_FTPWELCOME, "r")) != NULL) { 618 while (fgets(line, sizeof(line), fp) != NULL) { 619 line[strcspn(line, "\n")] = '\0'; 620 lreply(220, "%s", line); 621 } 622 (void) fflush(stdout); 623 (void) fclose(fp); 624 /* reply(220,) must follow */ 625 } 626 (void) gethostname(hostname, sizeof(hostname)); 627 628 /* Make sure hostname is fully qualified. */ 629 hp = gethostbyname(hostname); 630 if (hp != NULL) 631 strlcpy(hostname, hp->h_name, sizeof(hostname)); 632 633 if (multihome) { 634 error = getnameinfo((struct sockaddr *)&ctrl_addr, 635 ctrl_addr.su_len, dhostname, sizeof(dhostname), NULL, 0, 0); 636 } 637 638 if (error != 0) 639 reply(220, "FTP server ready."); 640 else 641 reply(220, "%s FTP server ready.", 642 (multihome ? dhostname : hostname)); 643 644 monitor_init(); 645 646 for (;;) 647 (void) yyparse(); 648 /* NOTREACHED */ 649} 650 651/* 652 * Signal handlers. 653 */ 654/*ARGSUSED*/ 655static void 656lostconn(int signo) 657{ 658 struct syslog_data sdata = SYSLOG_DATA_INIT; 659 660 sdata.log_fac = LOG_FTP; 661 if (debug) 662 syslog_r(LOG_DEBUG, &sdata, "lost connection"); 663 dologout(1); 664} 665 666static void 667sigquit(int signo) 668{ 669 struct syslog_data sdata = SYSLOG_DATA_INIT; 670 671 sdata.log_fac = LOG_FTP; 672 syslog_r(LOG_DEBUG, &sdata, "got signal %s", sys_signame[signo]); 673 dologout(1); 674} 675 676/* 677 * Save the result of a getpwnam. Used for USER command, since 678 * the data returned must not be clobbered by any other command 679 * (e.g., globbing). 680 */ 681static struct passwd * 682sgetpwnam(char *name, struct passwd *pw) 683{ 684 static struct passwd *save; 685 struct passwd *old; 686 687 if (pw == NULL && (pw = getpwnam(name)) == NULL) 688 return (NULL); 689 old = save; 690 save = pw_dup(pw); 691 if (save == NULL) { 692 perror_reply(421, "Local resource failure: malloc"); 693 dologout(1); 694 /* NOTREACHED */ 695 } 696 if (old) { 697 explicit_bzero(old->pw_passwd, strlen(old->pw_passwd)); 698 free(old); 699 } 700 return (save); 701} 702 703static int login_attempts; /* number of failed login attempts */ 704static int askpasswd; /* had user command, ask for passwd */ 705static char curname[LOGIN_NAME_MAX]; /* current USER name */ 706 707/* 708 * USER command. 709 * Sets global passwd pointer pw if named account exists and is acceptable; 710 * sets askpasswd if a PASS command is expected. If logged in previously, 711 * need to reset state. If name is "ftp" or "anonymous", the name is not in 712 * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return. 713 * If account doesn't exist, ask for passwd anyway. Otherwise, check user 714 * requesting login privileges. Disallow anyone who does not have a standard 715 * shell as returned by getusershell(). Disallow anyone mentioned in the file 716 * _PATH_FTPUSERS to allow people such as root and uucp to be avoided. 717 */ 718void 719user(char *name) 720{ 721 char *cp, *shell, *style, *host; 722 char *class = NULL; 723 724 if (logged_in) { 725 kill_slave("user already logged in"); 726 end_login(); 727 } 728 729 /* Close session from previous user if there was one. */ 730 if (as) { 731 auth_close(as); 732 as = NULL; 733 } 734 if (lc) { 735 login_close(lc); 736 lc = NULL; 737 } 738 739 if ((style = strchr(name, ':')) != NULL) 740 *style++ = 0; 741 742 guest = 0; 743 askpasswd = 0; 744 host = multihome ? dhostname : hostname; 745 if (anon_ok && 746 (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0)) { 747 if (checkuser(_PATH_FTPUSERS, "ftp") || 748 checkuser(_PATH_FTPUSERS, "anonymous")) 749 reply(530, "User %s access denied.", name); 750 else if ((pw = sgetpwnam("ftp", NULL)) != NULL) { 751 if ((lc = login_getclass(pw->pw_class)) == NULL || 752 (as = auth_open()) == NULL || 753 auth_setpwd(as, pw) != 0 || 754 auth_setoption(as, "FTPD_HOST", host) < 0) { 755 if (as) { 756 auth_close(as); 757 as = NULL; 758 } 759 if (lc) { 760 login_close(lc); 761 lc = NULL; 762 } 763 reply(421, "Local resource failure"); 764 return; 765 } 766 guest = 1; 767 askpasswd = 1; 768 reply(331, 769 "Guest login ok, send your email address as password."); 770 } else 771 reply(530, "User %s unknown.", name); 772 if (!askpasswd && logging) 773 syslog(LOG_NOTICE, 774 "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost); 775 return; 776 } 777 778 shell = _PATH_BSHELL; 779 if ((pw = sgetpwnam(name, NULL))) { 780 class = pw->pw_class; 781 if (pw->pw_shell != NULL && *pw->pw_shell != '\0') 782 shell = pw->pw_shell; 783 while ((cp = getusershell()) != NULL) 784 if (strcmp(cp, shell) == 0) 785 break; 786 shell = cp; 787 endusershell(); 788 } 789 790 /* Get login class; if invalid style treat like unknown user. */ 791 lc = login_getclass(class); 792 if (lc && (style = login_getstyle(lc, style, "auth-ftp")) == NULL) { 793 login_close(lc); 794 lc = NULL; 795 pw = NULL; 796 } 797 798 /* Do pre-authentication setup. */ 799 if (lc && ((as = auth_open()) == NULL || 800 (pw != NULL && auth_setpwd(as, pw) != 0) || 801 auth_setitem(as, AUTHV_STYLE, style) < 0 || 802 auth_setitem(as, AUTHV_NAME, name) < 0 || 803 auth_setitem(as, AUTHV_CLASS, class) < 0 || 804 auth_setoption(as, "login", "yes") < 0 || 805 auth_setoption(as, "notickets", "yes") < 0 || 806 auth_setoption(as, "FTPD_HOST", host) < 0)) { 807 if (as) { 808 auth_close(as); 809 as = NULL; 810 } 811 login_close(lc); 812 lc = NULL; 813 reply(421, "Local resource failure"); 814 return; 815 } 816 if (logging) 817 strlcpy(curname, name, sizeof(curname)); 818 819 dochroot = (lc && login_getcapbool(lc, "ftp-chroot", 0)) || 820 checkuser(_PATH_FTPCHROOT, name); 821 if (anon_only && !dochroot) { 822 reply(530, "User %s access denied.", name); 823 return; 824 } 825 if (pw) { 826 if (pw->pw_uid < minuid) { 827 reply(530, "User %s access denied.", name); 828 if (logging) 829 syslog(LOG_NOTICE, 830 "FTP LOGIN REFUSED FROM %s, %s (UID))", 831 remotehost, name); 832 return; 833 } 834 if ((!shell && !dochroot) || checkuser(_PATH_FTPUSERS, name)) { 835 reply(530, "User %s access denied.", name); 836 if (logging) 837 syslog(LOG_NOTICE, 838 "FTP LOGIN REFUSED FROM %s, %s", 839 remotehost, name); 840 pw = NULL; 841 return; 842 } 843 } 844 845 if (as != NULL && (cp = auth_challenge(as)) != NULL) 846 reply(331, "%s", cp); 847 else 848 reply(331, "Password required for %s.", name); 849 850 askpasswd = 1; 851 /* 852 * Delay before reading passwd after first failed 853 * attempt to slow down passwd-guessing programs. 854 */ 855 if (login_attempts) 856 sleep((unsigned) login_attempts); 857} 858 859/* 860 * Check if a user is in the file "fname" 861 */ 862static int 863checkuser(char *fname, char *name) 864{ 865 FILE *fp; 866 int found = 0; 867 char *p, line[BUFSIZ]; 868 869 if ((fp = fopen(fname, "r")) != NULL) { 870 while (fgets(line, sizeof(line), fp) != NULL) 871 if ((p = strchr(line, '\n')) != NULL) { 872 *p = '\0'; 873 if (line[0] == '#') 874 continue; 875 if (strcmp(line, name) == 0) { 876 found = 1; 877 break; 878 } 879 } 880 (void) fclose(fp); 881 } 882 return (found); 883} 884 885/* 886 * Terminate login as previous user, if any, resetting state; 887 * used when USER command is given or login fails. 888 */ 889static void 890end_login(void) 891{ 892 sigprocmask (SIG_BLOCK, &allsigs, NULL); 893 if (logged_in) { 894 if (!nowtmp) 895 ftpdlogwtmp(ttyline, "", ""); 896 if (doutmp) 897 ftpd_logout(utmp.ut_line); 898 } 899 reply(530, "Please reconnect to work as another user"); 900 _exit(0); 901} 902 903enum auth_ret 904pass(char *passwd) 905{ 906 int authok; 907 unsigned int flags; 908 FILE *fp; 909 static char homedir[PATH_MAX]; 910 char *motd, *dir, rootdir[PATH_MAX]; 911 size_t sz_pw_dir; 912 913 if (logged_in || askpasswd == 0) { 914 reply(503, "Login with USER first."); 915 return (AUTH_FAILED); 916 } 917 askpasswd = 0; 918 if (!guest) { /* "ftp" is only account allowed no password */ 919 authok = 0; 920 if (pw == NULL || pw->pw_passwd[0] == '\0') { 921 useconds_t us; 922 923 /* Sleep between 1 and 3 seconds to emulate a crypt. */ 924 us = arc4random_uniform(3000000); 925 usleep(us); 926 if (as != NULL) { 927 auth_close(as); 928 as = NULL; 929 } 930 } else { 931 authok = auth_userresponse(as, passwd, 0); 932 as = NULL; 933 } 934 if (authok == 0) { 935 reply(530, "Login incorrect."); 936 if (logging) 937 syslog(LOG_NOTICE, 938 "FTP LOGIN FAILED FROM %s, %s", 939 remotehost, curname); 940 pw = NULL; 941 if (login_attempts++ >= 5) { 942 syslog(LOG_NOTICE, 943 "repeated login failures from %s", 944 remotehost); 945 kill_slave("repeated login failures"); 946 _exit(0); 947 } 948 return (AUTH_FAILED); 949 } 950 } else if (lc != NULL) { 951 /* Save anonymous' password. */ 952 if (guestpw != NULL) 953 free(guestpw); 954 guestpw = strdup(passwd); 955 if (guestpw == NULL) { 956 kill_slave("out of mem"); 957 fatal("Out of memory."); 958 } 959 960 authok = auth_approval(as, lc, pw->pw_name, "ftp"); 961 auth_close(as); 962 as = NULL; 963 if (authok == 0) { 964 syslog(LOG_INFO|LOG_AUTH, 965 "FTP LOGIN FAILED (HOST) as %s: approval failure.", 966 pw->pw_name); 967 reply(530, "Approval failure."); 968 kill_slave("approval failure"); 969 _exit(0); 970 } 971 } else { 972 syslog(LOG_INFO|LOG_AUTH, 973 "FTP LOGIN CLASS %s MISSING for %s: approval failure.", 974 pw->pw_class, pw->pw_name); 975 reply(530, "Permission denied."); 976 kill_slave("permission denied"); 977 _exit(0); 978 } 979 980 if (monitor_post_auth() == 1) { 981 /* Post-auth monitor process */ 982 logged_in = 1; 983 return (AUTH_MONITOR); 984 } 985 986 login_attempts = 0; /* this time successful */ 987 /* set umask via setusercontext() unless -u flag was given. */ 988 flags = LOGIN_SETGROUP|LOGIN_SETPRIORITY|LOGIN_SETRESOURCES; 989 if (umaskchange) 990 flags |= LOGIN_SETUMASK; 991 else 992 (void) umask(defumask); 993 if (setusercontext(lc, pw, (uid_t)0, flags) != 0) { 994 perror_reply(421, "Local resource failure: setusercontext"); 995 syslog(LOG_NOTICE, "setusercontext: %m"); 996 dologout(1); 997 /* NOTREACHED */ 998 } 999 1000 /* open wtmp before chroot */ 1001 if (!nowtmp) 1002 ftpdlogwtmp(ttyline, pw->pw_name, remotehost); 1003 1004 /* open utmp before chroot */ 1005 if (doutmp) { 1006 memset((void *)&utmp, 0, sizeof(utmp)); 1007 (void)time(&utmp.ut_time); 1008 (void)strncpy(utmp.ut_name, pw->pw_name, sizeof(utmp.ut_name)); 1009 (void)strncpy(utmp.ut_host, remotehost, sizeof(utmp.ut_host)); 1010 (void)strncpy(utmp.ut_line, ttyline, sizeof(utmp.ut_line)); 1011 ftpd_login(&utmp); 1012 } 1013 1014 /* open stats file before chroot */ 1015 if (guest && (stats == 1) && (statfd < 0)) 1016 if ((statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND)) < 0) 1017 stats = 0; 1018 1019 logged_in = 1; 1020 1021 if ((dir = login_getcapstr(lc, "ftp-dir", NULL, NULL))) { 1022 char *newdir; 1023 1024 newdir = copy_dir(dir, pw); 1025 if (newdir == NULL) { 1026 perror_reply(421, "Local resource failure: malloc"); 1027 dologout(1); 1028 /* NOTREACHED */ 1029 } 1030 pw->pw_dir = newdir; 1031 pw = sgetpwnam(NULL, pw); 1032 free(dir); 1033 free(newdir); 1034 } 1035 1036 /* make sure pw->pw_dir is big enough to hold "/" */ 1037 sz_pw_dir = strlen(pw->pw_dir) + 1; 1038 if (sz_pw_dir < 2) { 1039 pw->pw_dir = "/"; 1040 pw = sgetpwnam(NULL, pw); 1041 sz_pw_dir = 2; 1042 } 1043 1044 if (guest || dochroot) { 1045 if (multihome && guest) { 1046 struct stat ts; 1047 1048 /* Compute root directory. */ 1049 snprintf(rootdir, sizeof(rootdir), "%s/%s", 1050 pw->pw_dir, dhostname); 1051 if (stat(rootdir, &ts) < 0) { 1052 snprintf(rootdir, sizeof(rootdir), "%s/%s", 1053 pw->pw_dir, hostname); 1054 } 1055 } else 1056 strlcpy(rootdir, pw->pw_dir, sizeof(rootdir)); 1057 } 1058 if (guest) { 1059 /* 1060 * We MUST do a chdir() after the chroot. Otherwise 1061 * the old current directory will be accessible as "." 1062 * outside the new root! 1063 */ 1064 if (chroot(rootdir) < 0 || chdir("/") < 0) { 1065 reply(550, "Can't set guest privileges."); 1066 goto bad; 1067 } 1068 strlcpy(pw->pw_dir, "/", sz_pw_dir); 1069 if (setenv("HOME", "/", 1) == -1) { 1070 reply(550, "Can't setup environment."); 1071 goto bad; 1072 } 1073 } else if (dochroot) { 1074 if (chroot(rootdir) < 0 || chdir("/") < 0) { 1075 reply(550, "Can't change root."); 1076 goto bad; 1077 } 1078 strlcpy(pw->pw_dir, "/", sz_pw_dir); 1079 if (setenv("HOME", "/", 1) == -1) { 1080 reply(550, "Can't setup environment."); 1081 goto bad; 1082 } 1083 } else if (chdir(pw->pw_dir) < 0) { 1084 if (chdir("/") < 0) { 1085 reply(530, "User %s: can't change directory to %s.", 1086 pw->pw_name, pw->pw_dir); 1087 goto bad; 1088 } else 1089 lreply(230, "No directory! Logging in with home=/"); 1090 } 1091 if (setegid(pw->pw_gid) < 0 || setgid(pw->pw_gid) < 0) { 1092 reply(550, "Can't set gid."); 1093 goto bad; 1094 } 1095 if (seteuid(pw->pw_uid) < 0 || setuid(pw->pw_uid) < 0) { 1096 reply(550, "Can't set uid."); 1097 goto bad; 1098 } 1099 sigprocmask(SIG_UNBLOCK, &allsigs, NULL); 1100 1101 /* 1102 * Set home directory so that use of ~ (tilde) works correctly. 1103 */ 1104 if (getcwd(homedir, PATH_MAX) != NULL) { 1105 if (setenv("HOME", homedir, 1) == -1) { 1106 reply(550, "Can't setup environment."); 1107 goto bad; 1108 } 1109 } 1110 1111 /* 1112 * Display a login message, if it exists. 1113 * N.B. reply(230,) must follow the message. 1114 */ 1115 motd = login_getcapstr(lc, "welcome", NULL, NULL); 1116 if ((fp = fopen(motd ? motd : _PATH_FTPLOGINMESG, "r")) != NULL) { 1117 char line[LINE_MAX]; 1118 1119 while (fgets(line, sizeof(line), fp) != NULL) { 1120 line[strcspn(line, "\n")] = '\0'; 1121 lreply(230, "%s", line); 1122 } 1123 (void) fflush(stdout); 1124 (void) fclose(fp); 1125 } 1126 if (motd != NULL) 1127 free(motd); 1128 if (guest) { 1129 reply(230, "Guest login ok, access restrictions apply."); 1130#ifdef HASSETPROCTITLE 1131 snprintf(proctitle, sizeof(proctitle), 1132 "%s: anonymous/%.*s", remotehost, 1133 (int)(sizeof(proctitle) - sizeof(remotehost) - 1134 sizeof(": anonymous/")), passwd); 1135 setproctitle("%s", proctitle); 1136#endif /* HASSETPROCTITLE */ 1137 if (logging) 1138 syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s", 1139 remotehost, passwd); 1140 } else { 1141 reply(230, "User %s logged in.", pw->pw_name); 1142#ifdef HASSETPROCTITLE 1143 snprintf(proctitle, sizeof(proctitle), 1144 "%s: %s", remotehost, pw->pw_name); 1145 setproctitle("%s", proctitle); 1146#endif /* HASSETPROCTITLE */ 1147 if (logging) 1148 syslog(LOG_INFO, "FTP LOGIN FROM %s as %s", 1149 remotehost, pw->pw_name); 1150 } 1151 login_close(lc); 1152 lc = NULL; 1153 return (AUTH_SLAVE); 1154bad: 1155 /* Forget all about it... */ 1156 login_close(lc); 1157 lc = NULL; 1158 end_login(); 1159 return (AUTH_FAILED); 1160} 1161 1162void 1163retrieve(char *cmd, char *name) 1164{ 1165 FILE *fin, *dout; 1166 struct stat st; 1167 int (*closefunc)(FILE *); 1168 time_t start; 1169 1170 if (cmd == 0) { 1171 fin = fopen(name, "r"), closefunc = fclose; 1172 st.st_size = 0; 1173 } else { 1174 char line[BUFSIZ]; 1175 1176 (void) snprintf(line, sizeof(line), cmd, name); 1177 name = line; 1178 fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose; 1179 st.st_size = -1; 1180 st.st_blksize = BUFSIZ; 1181 } 1182 if (fin == NULL) { 1183 if (errno != 0) { 1184 perror_reply(550, name); 1185 if (cmd == 0) { 1186 LOGCMD("get", name); 1187 } 1188 } 1189 return; 1190 } 1191 byte_count = -1; 1192 if (cmd == 0 && (fstat(fileno(fin), &st) < 0 || !S_ISREG(st.st_mode))) { 1193 reply(550, "%s: not a plain file.", name); 1194 goto done; 1195 } 1196 if (restart_point) { 1197 if (type == TYPE_A) { 1198 off_t i, n; 1199 int c; 1200 1201 n = restart_point; 1202 i = 0; 1203 while (i++ < n) { 1204 if ((c = getc(fin)) == EOF) { 1205 if (ferror(fin)) { 1206 perror_reply(550, name); 1207 goto done; 1208 } else 1209 break; 1210 } 1211 if (c == '\n') 1212 i++; 1213 } 1214 } else if (lseek(fileno(fin), restart_point, SEEK_SET) < 0) { 1215 perror_reply(550, name); 1216 goto done; 1217 } 1218 } 1219 dout = dataconn(name, st.st_size, "w"); 1220 if (dout == NULL) 1221 goto done; 1222 time(&start); 1223 send_data(fin, dout, (off_t)st.st_blksize, st.st_size, 1224 (restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode))); 1225 if ((cmd == 0) && stats) 1226 logxfer(name, byte_count, start); 1227 (void) fclose(dout); 1228 data = -1; 1229done: 1230 if (pdata >= 0) 1231 (void) close(pdata); 1232 pdata = -1; 1233 if (cmd == 0) 1234 LOGBYTES("get", name, byte_count); 1235 (*closefunc)(fin); 1236} 1237 1238void 1239store(char *name, char *mode, int unique) 1240{ 1241 FILE *fout, *din; 1242 int (*closefunc)(FILE *); 1243 struct stat st; 1244 int fd; 1245 1246 if (restart_point && *mode != 'a') 1247 mode = "r+"; 1248 1249 if (unique && stat(name, &st) == 0) { 1250 char *nam; 1251 1252 fd = guniquefd(name, &nam); 1253 if (fd == -1) { 1254 LOGCMD(*mode == 'w' ? "put" : "append", name); 1255 return; 1256 } 1257 name = nam; 1258 fout = fdopen(fd, mode); 1259 } else 1260 fout = fopen(name, mode); 1261 1262 closefunc = fclose; 1263 if (fout == NULL) { 1264 perror_reply(553, name); 1265 LOGCMD(*mode == 'w' ? "put" : "append", name); 1266 return; 1267 } 1268 byte_count = -1; 1269 if (restart_point) { 1270 if (type == TYPE_A) { 1271 off_t i, n; 1272 int c; 1273 1274 n = restart_point; 1275 i = 0; 1276 while (i++ < n) { 1277 if ((c = getc(fout)) == EOF) { 1278 if (ferror(fout)) { 1279 perror_reply(550, name); 1280 goto done; 1281 } else 1282 break; 1283 } 1284 if (c == '\n') 1285 i++; 1286 } 1287 /* 1288 * We must do this seek to "current" position 1289 * because we are changing from reading to 1290 * writing. 1291 */ 1292 if (fseek(fout, 0L, SEEK_CUR) < 0) { 1293 perror_reply(550, name); 1294 goto done; 1295 } 1296 } else if (lseek(fileno(fout), restart_point, SEEK_SET) < 0) { 1297 perror_reply(550, name); 1298 goto done; 1299 } 1300 } 1301 din = dataconn(name, (off_t)-1, "r"); 1302 if (din == NULL) 1303 goto done; 1304 if (receive_data(din, fout) == 0) { 1305 if (unique) 1306 reply(226, "Transfer complete (unique file name:%s).", 1307 name); 1308 else 1309 reply(226, "Transfer complete."); 1310 } 1311 (void) fclose(din); 1312 data = -1; 1313 pdata = -1; 1314done: 1315 LOGBYTES(*mode == 'w' ? "put" : "append", name, byte_count); 1316 (*closefunc)(fout); 1317} 1318 1319static FILE * 1320getdatasock(char *mode) 1321{ 1322 int on = 1, s, t, tries; 1323 1324 if (data >= 0) 1325 return (fdopen(data, mode)); 1326 sigprocmask (SIG_BLOCK, &allsigs, NULL); 1327 s = monitor_socket(ctrl_addr.su_family); 1328 if (s < 0) 1329 goto bad; 1330 if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, 1331 &on, sizeof(on)) < 0) 1332 goto bad; 1333 /* anchor socket to avoid multi-homing problems */ 1334 data_source = ctrl_addr; 1335 data_source.su_port = htons(20); /* ftp-data port */ 1336 for (tries = 1; ; tries++) { 1337 if (monitor_bind(s, (struct sockaddr *)&data_source, 1338 data_source.su_len) >= 0) 1339 break; 1340 if (errno != EADDRINUSE || tries > 10) 1341 goto bad; 1342 sleep((unsigned int)tries); 1343 } 1344 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1345 1346#ifdef IP_TOS 1347 if (ctrl_addr.su_family == AF_INET) { 1348 on = IPTOS_THROUGHPUT; 1349 if (setsockopt(s, IPPROTO_IP, IP_TOS, &on, 1350 sizeof(int)) < 0) 1351 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 1352 } 1353#endif 1354#ifdef TCP_NOPUSH 1355 /* 1356 * Turn off push flag to keep sender TCP from sending short packets 1357 * at the boundaries of each write(). Should probably do a SO_SNDBUF 1358 * to set the send buffer size as well, but that may not be desirable 1359 * in heavy-load situations. 1360 */ 1361 on = 1; 1362 if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, &on, sizeof(on)) < 0) 1363 syslog(LOG_WARNING, "setsockopt (TCP_NOPUSH): %m"); 1364#endif 1365#ifdef SO_SNDBUF 1366 on = 65536; 1367 if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, &on, sizeof(on)) < 0) 1368 syslog(LOG_WARNING, "setsockopt (SO_SNDBUF): %m"); 1369#endif 1370 1371 return (fdopen(s, mode)); 1372bad: 1373 /* Return the real value of errno (close may change it) */ 1374 t = errno; 1375 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1376 if (s >= 0) 1377 (void) close(s); 1378 errno = t; 1379 return (NULL); 1380} 1381 1382static FILE * 1383dataconn(char *name, off_t size, char *mode) 1384{ 1385 char sizebuf[32]; 1386 FILE *file = NULL; 1387 int retry = 0; 1388 in_port_t *p; 1389 u_char *fa, *ha; 1390 size_t alen; 1391 int error; 1392 1393 file_size = size; 1394 byte_count = 0; 1395 if (size != (off_t) -1) { 1396 (void) snprintf(sizebuf, sizeof(sizebuf), " (%qd bytes)", 1397 size); 1398 } else 1399 sizebuf[0] = '\0'; 1400 if (pdata >= 0) { 1401 union sockunion from; 1402 int s; 1403 socklen_t fromlen = sizeof(from); 1404 1405 (void) alarm ((unsigned) timeout); 1406 s = accept(pdata, (struct sockaddr *)&from, &fromlen); 1407 (void) alarm (0); 1408 if (s < 0) { 1409 reply(425, "Can't open data connection."); 1410 (void) close(pdata); 1411 pdata = -1; 1412 return (NULL); 1413 } 1414 switch (from.su_family) { 1415 case AF_INET: 1416 p = (in_port_t *)&from.su_sin.sin_port; 1417 fa = (u_char *)&from.su_sin.sin_addr; 1418 ha = (u_char *)&his_addr.su_sin.sin_addr; 1419 alen = sizeof(struct in_addr); 1420 break; 1421 case AF_INET6: 1422 p = (in_port_t *)&from.su_sin6.sin6_port; 1423 fa = (u_char *)&from.su_sin6.sin6_addr; 1424 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1425 alen = sizeof(struct in6_addr); 1426 break; 1427 default: 1428 reply(425, "Can't build data connection: " 1429 "unknown address family"); 1430 (void) close(pdata); 1431 (void) close(s); 1432 pdata = -1; 1433 return (NULL); 1434 } 1435 if (from.su_family != his_addr.su_family || 1436 ntohs(*p) < IPPORT_RESERVED) { 1437 reply(425, "Can't build data connection: " 1438 "address family or port error"); 1439 (void) close(pdata); 1440 (void) close(s); 1441 pdata = -1; 1442 return (NULL); 1443 } 1444 if (portcheck && memcmp(fa, ha, alen) != 0) { 1445 reply(425, "Can't build data connection: " 1446 "illegal port number"); 1447 (void) close(pdata); 1448 (void) close(s); 1449 pdata = -1; 1450 return (NULL); 1451 } 1452 (void) close(pdata); 1453 pdata = s; 1454 reply(150, "Opening %s mode data connection for '%s'%s.", 1455 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1456 return (fdopen(pdata, mode)); 1457 } 1458 if (data >= 0) { 1459 reply(125, "Using existing data connection for '%s'%s.", 1460 name, sizebuf); 1461 usedefault = 1; 1462 return (fdopen(data, mode)); 1463 } 1464 if (usedefault) 1465 data_dest = his_addr; 1466 usedefault = 1; 1467 do { 1468 if (file != NULL) 1469 (void) fclose(file); 1470 file = getdatasock(mode); 1471 if (file == NULL) { 1472 char hbuf[HOST_NAME_MAX+1], pbuf[10]; 1473 1474 error = getnameinfo((struct sockaddr *)&data_source, 1475 data_source.su_len, hbuf, sizeof(hbuf), pbuf, 1476 sizeof(pbuf), NI_NUMERICHOST | NI_NUMERICSERV); 1477 if (error != 0) 1478 reply(425, "Can't create data socket: %s.", 1479 strerror(errno)); 1480 else 1481 reply(425, 1482 "Can't create data socket (%s,%s): %s.", 1483 hbuf, pbuf, strerror(errno)); 1484 return (NULL); 1485 } 1486 1487 /* 1488 * attempt to connect to reserved port on client machine; 1489 * this looks like an attack 1490 */ 1491 switch (data_dest.su_family) { 1492 case AF_INET: 1493 p = (in_port_t *)&data_dest.su_sin.sin_port; 1494 fa = (u_char *)&data_dest.su_sin.sin_addr; 1495 ha = (u_char *)&his_addr.su_sin.sin_addr; 1496 alen = sizeof(struct in_addr); 1497 break; 1498 case AF_INET6: 1499 p = (in_port_t *)&data_dest.su_sin6.sin6_port; 1500 fa = (u_char *)&data_dest.su_sin6.sin6_addr; 1501 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1502 alen = sizeof(struct in6_addr); 1503 break; 1504 default: 1505 reply(425, "Can't build data connection: " 1506 "unknown address family"); 1507 (void) fclose(file); 1508 pdata = -1; 1509 return (NULL); 1510 } 1511 if (data_dest.su_family != his_addr.su_family || 1512 ntohs(*p) < IPPORT_RESERVED || ntohs(*p) == 2049) { /* XXX */ 1513 reply(425, "Can't build data connection: " 1514 "address family or port error"); 1515 (void) fclose(file); 1516 return NULL; 1517 } 1518 if (portcheck && memcmp(fa, ha, alen) != 0) { 1519 reply(435, "Can't build data connection: " 1520 "illegal port number"); 1521 (void) fclose(file); 1522 return NULL; 1523 } 1524 1525 if (connect(fileno(file), (struct sockaddr *)&data_dest, 1526 data_dest.su_len) == 0) { 1527 reply(150, "Opening %s mode data connection for '%s'%s.", 1528 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1529 data = fileno(file); 1530 return (file); 1531 } 1532 if (errno != EADDRINUSE) 1533 break; 1534 sleep((unsigned) swaitint); 1535 retry += swaitint; 1536 } while (retry <= swaitmax); 1537 perror_reply(425, "Can't build data connection"); 1538 (void) fclose(file); 1539 return (NULL); 1540} 1541 1542/* 1543 * Transfer the contents of "instr" to "outstr" peer using the appropriate 1544 * encapsulation of the data subject to Mode, Structure, and Type. 1545 * 1546 * NB: Form isn't handled. 1547 */ 1548static int 1549send_data(FILE *instr, FILE *outstr, off_t blksize, off_t filesize, int isreg) 1550{ 1551 int c, cnt, filefd, netfd; 1552 char *buf, *bp; 1553 size_t len; 1554 1555 transflag++; 1556 switch (type) { 1557 1558 case TYPE_A: 1559 while ((c = getc(instr)) != EOF) { 1560 if (recvurg) 1561 goto got_oob; 1562 byte_count++; 1563 if (c == '\n') { 1564 if (ferror(outstr)) 1565 goto data_err; 1566 (void) putc('\r', outstr); 1567 } 1568 (void) putc(c, outstr); 1569 } 1570 fflush(outstr); 1571 transflag = 0; 1572 if (ferror(instr)) 1573 goto file_err; 1574 if (ferror(outstr)) 1575 goto data_err; 1576 reply(226, "Transfer complete."); 1577 return(0); 1578 1579 case TYPE_I: 1580 case TYPE_L: 1581 /* 1582 * isreg is only set if we are not doing restart and we 1583 * are sending a regular file 1584 */ 1585 netfd = fileno(outstr); 1586 filefd = fileno(instr); 1587 1588 if (isreg && filesize < (off_t)16 * 1024 * 1024) { 1589 size_t fsize = (size_t)filesize; 1590 1591 if (fsize == 0) { 1592 transflag = 0; 1593 reply(226, "Transfer complete."); 1594 return(0); 1595 } 1596 1597 buf = mmap(0, fsize, PROT_READ, MAP_SHARED, filefd, 1598 (off_t)0); 1599 if (buf == MAP_FAILED) { 1600 syslog(LOG_WARNING, "mmap(%llu): %m", 1601 (unsigned long long)fsize); 1602 goto oldway; 1603 } 1604 bp = buf; 1605 len = fsize; 1606 do { 1607 cnt = write(netfd, bp, len); 1608 if (recvurg) { 1609 munmap(buf, fsize); 1610 goto got_oob; 1611 } 1612 len -= cnt; 1613 bp += cnt; 1614 if (cnt > 0) 1615 byte_count += cnt; 1616 } while(cnt > 0 && len > 0); 1617 1618 transflag = 0; 1619 munmap(buf, fsize); 1620 if (cnt < 0) 1621 goto data_err; 1622 reply(226, "Transfer complete."); 1623 return(0); 1624 } 1625 1626oldway: 1627 if ((buf = malloc((size_t)blksize)) == NULL) { 1628 transflag = 0; 1629 perror_reply(451, "Local resource failure: malloc"); 1630 return(-1); 1631 } 1632 1633 while ((cnt = read(filefd, buf, (size_t)blksize)) > 0 && 1634 write(netfd, buf, cnt) == cnt) 1635 byte_count += cnt; 1636 transflag = 0; 1637 (void)free(buf); 1638 if (cnt != 0) { 1639 if (cnt < 0) 1640 goto file_err; 1641 goto data_err; 1642 } 1643 reply(226, "Transfer complete."); 1644 return(0); 1645 default: 1646 transflag = 0; 1647 reply(550, "Unimplemented TYPE %d in send_data", type); 1648 return(-1); 1649 } 1650 1651data_err: 1652 transflag = 0; 1653 reply(426, "Data connection"); 1654 return(-1); 1655 1656file_err: 1657 transflag = 0; 1658 reply(551, "Error on input file"); 1659 return(-1); 1660 1661got_oob: 1662 myoob(); 1663 recvurg = 0; 1664 transflag = 0; 1665 return(-1); 1666} 1667 1668/* 1669 * Transfer data from peer to "outstr" using the appropriate encapulation of 1670 * the data subject to Mode, Structure, and Type. 1671 * 1672 * N.B.: Form isn't handled. 1673 */ 1674static int 1675receive_data(FILE *instr, FILE *outstr) 1676{ 1677 int c; 1678 int cnt; 1679 char buf[BUFSIZ]; 1680 struct sigaction sa, sa_saved; 1681 volatile int bare_lfs = 0; 1682 1683 transflag++; 1684 switch (type) { 1685 1686 case TYPE_I: 1687 case TYPE_L: 1688 memset(&sa, 0, sizeof(sa)); 1689 sigfillset(&sa.sa_mask); 1690 sa.sa_flags = SA_RESTART; 1691 sa.sa_handler = lostconn; 1692 (void) sigaction(SIGALRM, &sa, &sa_saved); 1693 do { 1694 (void) alarm ((unsigned) timeout); 1695 cnt = read(fileno(instr), buf, sizeof(buf)); 1696 (void) alarm (0); 1697 if (recvurg) 1698 goto got_oob; 1699 1700 if (cnt > 0) { 1701 if (write(fileno(outstr), buf, cnt) != cnt) 1702 goto file_err; 1703 byte_count += cnt; 1704 } 1705 } while (cnt > 0); 1706 (void) sigaction(SIGALRM, &sa_saved, NULL); 1707 if (cnt < 0) 1708 goto data_err; 1709 transflag = 0; 1710 return (0); 1711 1712 case TYPE_E: 1713 reply(553, "TYPE E not implemented."); 1714 transflag = 0; 1715 return (-1); 1716 1717 case TYPE_A: 1718 while ((c = getc(instr)) != EOF) { 1719 if (recvurg) 1720 goto got_oob; 1721 byte_count++; 1722 if (c == '\n') 1723 bare_lfs++; 1724 while (c == '\r') { 1725 if (ferror(outstr)) 1726 goto data_err; 1727 if ((c = getc(instr)) != '\n') { 1728 (void) putc ('\r', outstr); 1729 if (c == '\0' || c == EOF) 1730 goto contin2; 1731 } 1732 } 1733 (void) putc(c, outstr); 1734 contin2: ; 1735 } 1736 fflush(outstr); 1737 if (ferror(instr)) 1738 goto data_err; 1739 if (ferror(outstr)) 1740 goto file_err; 1741 transflag = 0; 1742 if (bare_lfs) { 1743 lreply(226, 1744 "WARNING! %d bare linefeeds received in ASCII mode", 1745 bare_lfs); 1746 printf(" File may not have transferred correctly.\r\n"); 1747 } 1748 return (0); 1749 default: 1750 reply(550, "Unimplemented TYPE %d in receive_data", type); 1751 transflag = 0; 1752 return (-1); 1753 } 1754 1755data_err: 1756 transflag = 0; 1757 reply(426, "Data Connection"); 1758 return (-1); 1759 1760file_err: 1761 transflag = 0; 1762 reply(452, "Error writing file"); 1763 return (-1); 1764 1765got_oob: 1766 myoob(); 1767 recvurg = 0; 1768 transflag = 0; 1769 return (-1); 1770} 1771 1772void 1773statfilecmd(char *filename) 1774{ 1775 FILE *fin; 1776 int c; 1777 int atstart; 1778 char line[LINE_MAX]; 1779 1780 (void)snprintf(line, sizeof(line), "/bin/ls -lgA %s", filename); 1781 fin = ftpd_popen(line, "r"); 1782 if (fin == NULL) { 1783 reply(451, "Local resource failure"); 1784 return; 1785 } 1786 lreply(211, "status of %s:", filename); 1787 atstart = 1; 1788 while ((c = getc(fin)) != EOF) { 1789 if (c == '\n') { 1790 if (ferror(stdout)){ 1791 perror_reply(421, "control connection"); 1792 (void) ftpd_pclose(fin); 1793 dologout(1); 1794 /* NOTREACHED */ 1795 } 1796 if (ferror(fin)) { 1797 perror_reply(551, filename); 1798 (void) ftpd_pclose(fin); 1799 return; 1800 } 1801 (void) putc('\r', stdout); 1802 } 1803 if (atstart && isdigit(c)) 1804 (void) putc(' ', stdout); 1805 (void) putc(c, stdout); 1806 atstart = (c == '\n'); 1807 } 1808 (void) ftpd_pclose(fin); 1809 reply(211, "End of Status"); 1810} 1811 1812void 1813statcmd(void) 1814{ 1815 union sockunion *su; 1816 u_char *a, *p; 1817 char hbuf[HOST_NAME_MAX+1]; 1818 int ispassive; 1819 int error; 1820 1821 lreply(211, "%s FTP server status:", hostname); 1822 error = getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len, 1823 hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST); 1824 printf(" Connected to %s", remotehost); 1825 if (error == 0 && strcmp(remotehost, hbuf) != 0) 1826 printf(" (%s)", hbuf); 1827 printf("\r\n"); 1828 if (logged_in) { 1829 if (guest) 1830 printf(" Logged in anonymously\r\n"); 1831 else 1832 printf(" Logged in as %s\r\n", pw->pw_name); 1833 } else if (askpasswd) 1834 printf(" Waiting for password\r\n"); 1835 else 1836 printf(" Waiting for user name\r\n"); 1837 printf(" TYPE: %s", typenames[type]); 1838 if (type == TYPE_A || type == TYPE_E) 1839 printf(", FORM: %s", formnames[form]); 1840 if (type == TYPE_L) 1841#if NBBY == 8 1842 printf(" %d", NBBY); 1843#else 1844 printf(" %d", bytesize); /* need definition! */ 1845#endif 1846 printf("; STRUcture: %s; transfer MODE: %s\r\n", 1847 strunames[stru], modenames[mode]); 1848 ispassive = 0; 1849 if (data != -1) 1850 printf(" Data connection open\r\n"); 1851 else if (pdata != -1) { 1852 printf(" in Passive mode\r\n"); 1853 su = (union sockunion *)&pasv_addr; 1854 ispassive++; 1855 goto printaddr; 1856 } else if (usedefault == 0) { 1857 size_t alen; 1858 int af, i; 1859 1860 su = (union sockunion *)&data_dest; 1861printaddr: 1862 /* PASV/PORT */ 1863 if (su->su_family == AF_INET) { 1864 if (ispassive) 1865 printf("211- PASV "); 1866 else 1867 printf("211- PORT "); 1868 a = (u_char *)&su->su_sin.sin_addr; 1869 p = (u_char *)&su->su_sin.sin_port; 1870 printf("(%u,%u,%u,%u,%u,%u)\r\n", 1871 a[0], a[1], a[2], a[3], 1872 p[0], p[1]); 1873 } 1874 1875 /* LPSV/LPRT */ 1876 alen = 0; 1877 switch (su->su_family) { 1878 case AF_INET: 1879 a = (u_char *)&su->su_sin.sin_addr; 1880 p = (u_char *)&su->su_sin.sin_port; 1881 alen = sizeof(su->su_sin.sin_addr); 1882 af = 4; 1883 break; 1884 case AF_INET6: 1885 a = (u_char *)&su->su_sin6.sin6_addr; 1886 p = (u_char *)&su->su_sin6.sin6_port; 1887 alen = sizeof(su->su_sin6.sin6_addr); 1888 af = 6; 1889 break; 1890 default: 1891 af = 0; 1892 break; 1893 } 1894 if (af) { 1895 if (ispassive) 1896 printf("211- LPSV "); 1897 else 1898 printf("211- LPRT "); 1899 printf("(%u,%llu", af, (unsigned long long)alen); 1900 for (i = 0; i < alen; i++) 1901 printf(",%u", a[i]); 1902 printf(",%u,%u,%u)\r\n", 2, p[0], p[1]); 1903 } 1904 1905 /* EPRT/EPSV */ 1906 switch (su->su_family) { 1907 case AF_INET: 1908 af = 1; 1909 break; 1910 case AF_INET6: 1911 af = 2; 1912 break; 1913 default: 1914 af = 0; 1915 break; 1916 } 1917 if (af) { 1918 char pbuf[10]; 1919 union sockunion tmp = *su; 1920 1921 if (tmp.su_family == AF_INET6) 1922 tmp.su_sin6.sin6_scope_id = 0; 1923 if (getnameinfo((struct sockaddr *)&tmp, tmp.su_len, 1924 hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), 1925 NI_NUMERICHOST | NI_NUMERICSERV) == 0) { 1926 if (ispassive) 1927 printf("211- EPSV "); 1928 else 1929 printf("211- EPRT "); 1930 printf("(|%u|%s|%s|)\r\n", 1931 af, hbuf, pbuf); 1932 } 1933 } 1934 } else 1935 printf(" No data connection\r\n"); 1936 reply(211, "End of status"); 1937} 1938 1939void 1940fatal(char *s) 1941{ 1942 1943 reply(451, "Error in server: %s", s); 1944 reply(221, "Closing connection due to server error."); 1945 dologout(0); 1946 /* NOTREACHED */ 1947} 1948 1949void 1950reply(int n, const char *fmt, ...) 1951{ 1952 char *buf, *p, *next; 1953 int rval; 1954 va_list ap; 1955 1956 va_start(ap, fmt); 1957 rval = vasprintf(&buf, fmt, ap); 1958 va_end(ap); 1959 if (rval == -1 || buf == NULL) { 1960 printf("421 Local resource failure: malloc\r\n"); 1961 fflush(stdout); 1962 dologout(1); 1963 } 1964 next = buf; 1965 while ((p = strsep(&next, "\n\r"))) { 1966 printf("%d%s %s\r\n", n, (next != '\0') ? "-" : "", p); 1967 if (debug) 1968 syslog(LOG_DEBUG, "<--- %d%s %s", n, 1969 (next != '\0') ? "-" : "", p); 1970 } 1971 (void)fflush(stdout); 1972 free(buf); 1973} 1974 1975 1976void 1977reply_r(int n, const char *fmt, ...) 1978{ 1979 char *p, *next; 1980 char msg[BUFSIZ]; 1981 char buf[BUFSIZ]; 1982 va_list ap; 1983 struct syslog_data sdata = SYSLOG_DATA_INIT; 1984 1985 sdata.log_fac = LOG_FTP; 1986 va_start(ap, fmt); 1987 vsnprintf(msg, sizeof(msg), fmt, ap); 1988 va_end(ap); 1989 1990 next = msg; 1991 1992 while ((p = strsep(&next, "\n\r"))) { 1993 snprintf(buf, sizeof(buf), "%d%s %s\r\n", n, 1994 (next != '\0') ? "-" : "", p); 1995 write(STDOUT_FILENO, buf, strlen(buf)); 1996 if (debug) { 1997 buf[strlen(buf) - 2] = '\0'; 1998 syslog_r(LOG_DEBUG, &sdata, "<--- %s", buf); 1999 } 2000 } 2001} 2002 2003void 2004lreply(int n, const char *fmt, ...) 2005{ 2006 va_list ap; 2007 2008 va_start(ap, fmt); 2009 (void)printf("%d- ", n); 2010 (void)vprintf(fmt, ap); 2011 va_end(ap); 2012 (void)printf("\r\n"); 2013 (void)fflush(stdout); 2014 if (debug) { 2015 va_start(ap, fmt); 2016 syslog(LOG_DEBUG, "<--- %d- ", n); 2017 vsyslog(LOG_DEBUG, fmt, ap); 2018 va_end(ap); 2019 } 2020} 2021 2022static void 2023ack(char *s) 2024{ 2025 2026 reply(250, "%s command successful.", s); 2027} 2028 2029void 2030nack(char *s) 2031{ 2032 2033 reply(502, "%s command not implemented.", s); 2034} 2035 2036/* ARGSUSED */ 2037void 2038yyerror(char *s) 2039{ 2040 cbuf[strcspn(cbuf, "\n")] = '\0'; 2041 reply(500, "'%s': command not understood.", cbuf); 2042} 2043 2044void 2045delete(char *name) 2046{ 2047 struct stat st; 2048 2049 LOGCMD("delete", name); 2050 if (stat(name, &st) < 0) { 2051 perror_reply(550, name); 2052 return; 2053 } 2054 if ((st.st_mode&S_IFMT) == S_IFDIR) { 2055 if (rmdir(name) < 0) { 2056 perror_reply(550, name); 2057 return; 2058 } 2059 goto done; 2060 } 2061 if (unlink(name) < 0) { 2062 perror_reply(550, name); 2063 return; 2064 } 2065done: 2066 ack("DELE"); 2067} 2068 2069void 2070cwd(char *path) 2071{ 2072 FILE *message; 2073 2074 if (chdir(path) < 0) 2075 perror_reply(550, path); 2076 else { 2077 if ((message = fopen(_PATH_CWDMESG, "r")) != NULL) { 2078 char line[LINE_MAX]; 2079 2080 while (fgets(line, sizeof(line), message) != NULL) { 2081 line[strcspn(line, "\n")] = '\0'; 2082 lreply(250, "%s", line); 2083 } 2084 (void) fflush(stdout); 2085 (void) fclose(message); 2086 } 2087 ack("CWD"); 2088 } 2089} 2090 2091void 2092replydirname(const char *name, const char *message) 2093{ 2094 char *p, *ep; 2095 char npath[PATH_MAX * 2]; 2096 2097 p = npath; 2098 ep = &npath[sizeof(npath) - 1]; 2099 while (*name) { 2100 if (*name == '"') { 2101 if (ep - p < 2) 2102 break; 2103 *p++ = *name++; 2104 *p++ = '"'; 2105 } else { 2106 if (ep - p < 1) 2107 break; 2108 *p++ = *name++; 2109 } 2110 } 2111 *p = '\0'; 2112 reply(257, "\"%s\" %s", npath, message); 2113} 2114 2115void 2116makedir(char *name) 2117{ 2118 2119 LOGCMD("mkdir", name); 2120 if (mkdir(name, 0777) < 0) 2121 perror_reply(550, name); 2122 else 2123 replydirname(name, "directory created."); 2124} 2125 2126void 2127removedir(char *name) 2128{ 2129 2130 LOGCMD("rmdir", name); 2131 if (rmdir(name) < 0) 2132 perror_reply(550, name); 2133 else 2134 ack("RMD"); 2135} 2136 2137void 2138pwd(void) 2139{ 2140 char path[PATH_MAX]; 2141 2142 if (getcwd(path, sizeof(path)) == NULL) 2143 perror_reply(550, "Can't get current directory"); 2144 else 2145 replydirname(path, "is current directory."); 2146} 2147 2148char * 2149renamefrom(char *name) 2150{ 2151 struct stat st; 2152 2153 if (stat(name, &st) < 0) { 2154 perror_reply(550, name); 2155 return ((char *)0); 2156 } 2157 reply(350, "File exists, ready for destination name"); 2158 return (name); 2159} 2160 2161void 2162renamecmd(char *from, char *to) 2163{ 2164 2165 LOGCMD2("rename", from, to); 2166 if (rename(from, to) < 0) 2167 perror_reply(550, "rename"); 2168 else 2169 ack("RNTO"); 2170} 2171 2172static void 2173dolog(struct sockaddr *sa) 2174{ 2175 char hbuf[sizeof(remotehost)]; 2176 2177 if (getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), NULL, 0, 0) == 0) 2178 (void) strlcpy(remotehost, hbuf, sizeof(remotehost)); 2179 else 2180 (void) strlcpy(remotehost, "unknown", sizeof(remotehost)); 2181 2182#ifdef HASSETPROCTITLE 2183 snprintf(proctitle, sizeof(proctitle), "%s: connected", remotehost); 2184 setproctitle("%s", proctitle); 2185#endif /* HASSETPROCTITLE */ 2186 2187 if (logging) { 2188 int error; 2189 error = getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), 2190 NULL, 0, NI_NUMERICHOST); 2191 syslog(LOG_INFO, "connection from %s [%s]", remotehost, 2192 error ? gai_strerror(error) : hbuf); 2193 } 2194} 2195 2196/* 2197 * Record logout in wtmp file and exit with supplied status. 2198 * NOTE: because this is called from signal handlers it cannot 2199 * use stdio (or call other functions that use stdio). 2200 */ 2201void 2202dologout(int status) 2203{ 2204 2205 transflag = 0; 2206 2207 if (logged_in) { 2208 sigprocmask(SIG_BLOCK, &allsigs, NULL); 2209 if (!nowtmp) 2210 ftpdlogwtmp(ttyline, "", ""); 2211 if (doutmp) 2212 ftpd_logout(utmp.ut_line); 2213 } 2214 /* beware of flushing buffers after a SIGPIPE */ 2215 _exit(status); 2216} 2217 2218/*ARGSUSED*/ 2219static void 2220sigurg(int signo) 2221{ 2222 2223 recvurg = 1; 2224} 2225 2226static void 2227myoob(void) 2228{ 2229 char *cp; 2230 int ret; 2231 2232 /* only process if transfer occurring */ 2233 if (!transflag) 2234 return; 2235 cp = tmpline; 2236 ret = get_line(cp, sizeof(tmpline)-1, stdin); 2237 if (ret == -1) { 2238 reply(221, "You could at least say goodbye."); 2239 dologout(0); 2240 } else if (ret == -2) { 2241 /* Ignore truncated command */ 2242 return; 2243 } 2244 upper(cp); 2245 if (strcmp(cp, "ABOR\r\n") == 0) { 2246 tmpline[0] = '\0'; 2247 reply(426, "Transfer aborted. Data connection closed."); 2248 reply(226, "Abort successful"); 2249 } 2250 if (strcmp(cp, "STAT\r\n") == 0) { 2251 tmpline[0] = '\0'; 2252 if (file_size != (off_t) -1) 2253 reply(213, "Status: %qd of %qd bytes transferred", 2254 byte_count, file_size); 2255 else 2256 reply(213, "Status: %qd bytes transferred", byte_count); 2257 } 2258} 2259 2260/* 2261 * Note: a response of 425 is not mentioned as a possible response to 2262 * the PASV command in RFC959. However, it has been blessed as 2263 * a legitimate response by Jon Postel in a telephone conversation 2264 * with Rick Adams on 25 Jan 89. 2265 */ 2266void 2267passive(void) 2268{ 2269 socklen_t len; 2270 int on = 1; 2271 u_char *p, *a; 2272 2273 if (pw == NULL) { 2274 reply(530, "Please login with USER and PASS"); 2275 return; 2276 } 2277 if (pdata >= 0) 2278 close(pdata); 2279 /* 2280 * XXX 2281 * At this point, it would be nice to have an algorithm that 2282 * inserted a growing delay in an attack scenario. Such a thing 2283 * would look like continual passive sockets being opened, but 2284 * nothing serious being done with them. They're not used to 2285 * move data; the entire attempt is just to use tcp FIN_WAIT 2286 * resources. 2287 */ 2288 pdata = socket(AF_INET, SOCK_STREAM, 0); 2289 if (pdata < 0) { 2290 perror_reply(425, "Can't open passive connection"); 2291 return; 2292 } 2293 2294 if (setsockopt(pdata, SOL_SOCKET, SO_KEEPALIVE, 2295 &on, sizeof(on)) < 0) 2296 goto pasv_error; 2297 2298 on = IP_PORTRANGE_HIGH; 2299 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2300 &on, sizeof(on)) < 0) 2301 goto pasv_error; 2302 2303 pasv_addr = ctrl_addr; 2304 pasv_addr.su_sin.sin_port = 0; 2305 if (bind(pdata, (struct sockaddr *)&pasv_addr, 2306 pasv_addr.su_len) < 0) 2307 goto pasv_error; 2308 2309 len = sizeof(pasv_addr); 2310 if (getsockname(pdata, (struct sockaddr *)&pasv_addr, &len) < 0) 2311 goto pasv_error; 2312 if (listen(pdata, 1) < 0) 2313 goto pasv_error; 2314 a = (u_char *)&pasv_addr.su_sin.sin_addr; 2315 p = (u_char *)&pasv_addr.su_sin.sin_port; 2316 2317 reply(227, "Entering Passive Mode (%u,%u,%u,%u,%u,%u)", a[0], 2318 a[1], a[2], a[3], p[0], p[1]); 2319 return; 2320 2321pasv_error: 2322 perror_reply(425, "Can't open passive connection"); 2323 (void) close(pdata); 2324 pdata = -1; 2325 return; 2326} 2327 2328int 2329epsvproto2af(int proto) 2330{ 2331 2332 switch (proto) { 2333 case 1: return AF_INET; 2334#ifdef INET6 2335 case 2: return AF_INET6; 2336#endif 2337 default: return -1; 2338 } 2339} 2340 2341int 2342af2epsvproto(int af) 2343{ 2344 2345 switch (af) { 2346 case AF_INET: return 1; 2347#ifdef INET6 2348 case AF_INET6: return 2; 2349#endif 2350 default: return -1; 2351 } 2352} 2353 2354/* 2355 * 228 Entering Long Passive Mode (af, hal, h1, h2, h3,..., pal, p1, p2...) 2356 * 229 Entering Extended Passive Mode (|||port|) 2357 */ 2358void 2359long_passive(char *cmd, int pf) 2360{ 2361 socklen_t len; 2362 int on = 1; 2363 u_char *p, *a; 2364 2365 if (!logged_in) { 2366 syslog(LOG_NOTICE, "long passive but not logged in"); 2367 reply(503, "Login with USER first."); 2368 return; 2369 } 2370 2371 if (pf != PF_UNSPEC && ctrl_addr.su_family != pf) { 2372 /* 2373 * XXX 2374 * only EPRT/EPSV ready clients will understand this 2375 */ 2376 if (strcmp(cmd, "EPSV") != 0) 2377 reply(501, "Network protocol mismatch"); /*XXX*/ 2378 else 2379 epsv_protounsupp("Network protocol mismatch"); 2380 2381 return; 2382 } 2383 2384 if (pdata >= 0) 2385 close(pdata); 2386 /* 2387 * XXX 2388 * At this point, it would be nice to have an algorithm that 2389 * inserted a growing delay in an attack scenario. Such a thing 2390 * would look like continual passive sockets being opened, but 2391 * nothing serious being done with them. They not used to move 2392 * data; the entire attempt is just to use tcp FIN_WAIT 2393 * resources. 2394 */ 2395 pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 2396 if (pdata < 0) { 2397 perror_reply(425, "Can't open passive connection"); 2398 return; 2399 } 2400 2401 if (setsockopt(pdata, SOL_SOCKET, SO_KEEPALIVE, 2402 &on, sizeof(on)) < 0) 2403 goto pasv_error; 2404 2405 switch (ctrl_addr.su_family) { 2406 case AF_INET: 2407 on = IP_PORTRANGE_HIGH; 2408 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2409 &on, sizeof(on)) < 0) 2410 goto pasv_error; 2411 break; 2412 case AF_INET6: 2413 on = IPV6_PORTRANGE_HIGH; 2414 if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE, 2415 &on, sizeof(on)) < 0) 2416 goto pasv_error; 2417 break; 2418 } 2419 2420 pasv_addr = ctrl_addr; 2421 pasv_addr.su_port = 0; 2422 if (bind(pdata, (struct sockaddr *)&pasv_addr, pasv_addr.su_len) < 0) 2423 goto pasv_error; 2424 len = pasv_addr.su_len; 2425 if (getsockname(pdata, (struct sockaddr *)&pasv_addr, &len) < 0) 2426 goto pasv_error; 2427 if (listen(pdata, 1) < 0) 2428 goto pasv_error; 2429 p = (u_char *)&pasv_addr.su_port; 2430 2431 if (strcmp(cmd, "LPSV") == 0) { 2432 switch (pasv_addr.su_family) { 2433 case AF_INET: 2434 a = (u_char *)&pasv_addr.su_sin.sin_addr; 2435 reply(228, 2436 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2437 4, 4, a[0], a[1], a[2], a[3], 2, p[0], p[1]); 2438 return; 2439 case AF_INET6: 2440 a = (u_char *)&pasv_addr.su_sin6.sin6_addr; 2441 reply(228, 2442 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u," 2443 "%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2444 6, 16, a[0], a[1], a[2], a[3], a[4], 2445 a[5], a[6], a[7], a[8], a[9], a[10], 2446 a[11], a[12], a[13], a[14], a[15], 2447 2, p[0], p[1]); 2448 return; 2449 } 2450 } else if (strcmp(cmd, "EPSV") == 0) { 2451 switch (pasv_addr.su_family) { 2452 case AF_INET: 2453 case AF_INET6: 2454 reply(229, "Entering Extended Passive Mode (|||%u|)", 2455 ntohs(pasv_addr.su_port)); 2456 return; 2457 } 2458 } else { 2459 /* more proper error code? */ 2460 } 2461 2462 pasv_error: 2463 perror_reply(425, "Can't open passive connection"); 2464 (void) close(pdata); 2465 pdata = -1; 2466 return; 2467} 2468 2469/* 2470 * EPRT |proto|addr|port| 2471 */ 2472int 2473extended_port(const char *arg) 2474{ 2475 char *tmp = NULL; 2476 char *result[3]; 2477 char *p, *q; 2478 char delim; 2479 struct addrinfo hints; 2480 struct addrinfo *res = NULL; 2481 int i; 2482 unsigned long proto; 2483 2484 if (epsvall) { 2485 reply(501, "EPRT disallowed after EPSV ALL"); 2486 return -1; 2487 } 2488 2489 usedefault = 0; 2490 if (pdata >= 0) { 2491 (void) close(pdata); 2492 pdata = -1; 2493 } 2494 2495 tmp = strdup(arg); 2496 if (!tmp) { 2497 fatal("not enough core."); 2498 /*NOTREACHED*/ 2499 } 2500 p = tmp; 2501 delim = p[0]; 2502 p++; 2503 memset(result, 0, sizeof(result)); 2504 for (i = 0; i < 3; i++) { 2505 q = strchr(p, delim); 2506 if (!q || *q != delim) 2507 goto parsefail; 2508 *q++ = '\0'; 2509 result[i] = p; 2510 p = q; 2511 } 2512 2513 /* some more sanity check */ 2514 p = NULL; 2515 (void)strtoul(result[2], &p, 10); 2516 if (!*result[2] || *p) 2517 goto protounsupp; 2518 p = NULL; 2519 proto = strtoul(result[0], &p, 10); 2520 if (!*result[0] || *p) 2521 goto protounsupp; 2522 2523 memset(&hints, 0, sizeof(hints)); 2524 hints.ai_family = epsvproto2af((int)proto); 2525 if (hints.ai_family < 0) 2526 goto protounsupp; 2527 hints.ai_socktype = SOCK_STREAM; 2528 hints.ai_flags = AI_NUMERICHOST; /*no DNS*/ 2529 if (getaddrinfo(result[1], result[2], &hints, &res)) 2530 goto parsefail; 2531 if (res->ai_next) 2532 goto parsefail; 2533 if (sizeof(data_dest) < res->ai_addrlen) 2534 goto parsefail; 2535 memcpy(&data_dest, res->ai_addr, res->ai_addrlen); 2536 if (his_addr.su_family == AF_INET6 && 2537 data_dest.su_family == AF_INET6) { 2538 /* XXX more sanity checks! */ 2539 data_dest.su_sin6.sin6_scope_id = 2540 his_addr.su_sin6.sin6_scope_id; 2541 } 2542 if (pdata >= 0) { 2543 (void) close(pdata); 2544 pdata = -1; 2545 } 2546 reply(200, "EPRT command successful."); 2547 2548 if (tmp) 2549 free(tmp); 2550 if (res) 2551 freeaddrinfo(res); 2552 return 0; 2553 2554parsefail: 2555 reply(500, "Invalid argument, rejected."); 2556 usedefault = 1; 2557 if (tmp) 2558 free(tmp); 2559 if (res) 2560 freeaddrinfo(res); 2561 return -1; 2562 2563protounsupp: 2564 epsv_protounsupp("Protocol not supported"); 2565 usedefault = 1; 2566 if (tmp) 2567 free(tmp); 2568 if (res) 2569 freeaddrinfo(res); 2570 return -1; 2571} 2572 2573/* 2574 * 522 Protocol not supported (proto,...) 2575 * as we assume address family for control and data connections are the same, 2576 * we do not return the list of address families we support - instead, we 2577 * return the address family of the control connection. 2578 */ 2579void 2580epsv_protounsupp(const char *message) 2581{ 2582 int proto; 2583 2584 proto = af2epsvproto(ctrl_addr.su_family); 2585 if (proto < 0) 2586 reply(501, "%s", message); /*XXX*/ 2587 else 2588 reply(522, "%s, use (%d)", message, proto); 2589} 2590 2591/* 2592 * Generate unique name for file with basename "local". 2593 * The file named "local" is already known to exist. 2594 * Generates failure reply on error. 2595 */ 2596static int 2597guniquefd(char *local, char **nam) 2598{ 2599 static char new[PATH_MAX]; 2600 struct stat st; 2601 int count, len, fd; 2602 char *cp; 2603 2604 cp = strrchr(local, '/'); 2605 if (cp) 2606 *cp = '\0'; 2607 if (stat(cp ? local : ".", &st) < 0) { 2608 perror_reply(553, cp ? local : "."); 2609 return (-1); 2610 } 2611 if (cp) 2612 *cp = '/'; 2613 len = strlcpy(new, local, sizeof(new)); 2614 if (len+2+1 >= sizeof(new)-1) 2615 return (-1); 2616 cp = new + len; 2617 *cp++ = '.'; 2618 for (count = 1; count < 100; count++) { 2619 (void)snprintf(cp, sizeof(new) - (cp - new), "%d", count); 2620 fd = open(new, O_RDWR|O_CREAT|O_EXCL, 0666); 2621 if (fd == -1) 2622 continue; 2623 if (nam) 2624 *nam = new; 2625 return (fd); 2626 } 2627 reply(452, "Unique file name cannot be created."); 2628 return (-1); 2629} 2630 2631/* 2632 * Format and send reply containing system error number. 2633 */ 2634void 2635perror_reply(int code, char *string) 2636{ 2637 2638 reply(code, "%s: %s.", string, strerror(errno)); 2639} 2640 2641static char *onefile[] = { 2642 "", 2643 0 2644}; 2645 2646void 2647send_file_list(char *whichf) 2648{ 2649 struct stat st; 2650 DIR *dirp = NULL; 2651 struct dirent *dir; 2652 FILE *dout = NULL; 2653 char **dirlist; 2654 char *dirname; 2655 int simple = 0; 2656 volatile int freeglob = 0; 2657 glob_t gl; 2658 2659 if (strpbrk(whichf, "~{[*?") != NULL) { 2660 memset(&gl, 0, sizeof(gl)); 2661 freeglob = 1; 2662 if (glob(whichf, 2663 GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE|GLOB_LIMIT, 2664 0, &gl)) { 2665 reply(550, "not found"); 2666 goto out; 2667 } else if (gl.gl_pathc == 0) { 2668 errno = ENOENT; 2669 perror_reply(550, whichf); 2670 goto out; 2671 } 2672 dirlist = gl.gl_pathv; 2673 } else { 2674 onefile[0] = whichf; 2675 dirlist = onefile; 2676 simple = 1; 2677 } 2678 2679 while ((dirname = *dirlist++)) { 2680 if (stat(dirname, &st) < 0) { 2681 /* 2682 * If user typed "ls -l", etc, and the client 2683 * used NLST, do what the user meant. 2684 */ 2685 if (dirname[0] == '-' && *dirlist == NULL && 2686 transflag == 0) { 2687 retrieve("/bin/ls %s", dirname); 2688 goto out; 2689 } 2690 perror_reply(550, whichf); 2691 if (dout != NULL) { 2692 (void) fclose(dout); 2693 transflag = 0; 2694 data = -1; 2695 pdata = -1; 2696 } 2697 goto out; 2698 } 2699 2700 if (S_ISREG(st.st_mode)) { 2701 if (dout == NULL) { 2702 dout = dataconn("file list", (off_t)-1, "w"); 2703 if (dout == NULL) 2704 goto out; 2705 transflag++; 2706 } 2707 fprintf(dout, "%s%s\n", dirname, 2708 type == TYPE_A ? "\r" : ""); 2709 byte_count += strlen(dirname) + 1; 2710 continue; 2711 } else if (!S_ISDIR(st.st_mode)) 2712 continue; 2713 2714 if ((dirp = opendir(dirname)) == NULL) 2715 continue; 2716 2717 while ((dir = readdir(dirp)) != NULL) { 2718 char nbuf[PATH_MAX]; 2719 2720 if (recvurg) { 2721 myoob(); 2722 recvurg = 0; 2723 transflag = 0; 2724 goto out; 2725 } 2726 2727 if (dir->d_name[0] == '.' && dir->d_namlen == 1) 2728 continue; 2729 if (dir->d_name[0] == '.' && dir->d_name[1] == '.' && 2730 dir->d_namlen == 2) 2731 continue; 2732 2733 snprintf(nbuf, sizeof(nbuf), "%s/%s", dirname, 2734 dir->d_name); 2735 2736 /* 2737 * We have to do a stat to insure it's 2738 * not a directory or special file. 2739 */ 2740 if (simple || (stat(nbuf, &st) == 0 && 2741 S_ISREG(st.st_mode))) { 2742 if (dout == NULL) { 2743 dout = dataconn("file list", (off_t)-1, 2744 "w"); 2745 if (dout == NULL) 2746 goto out; 2747 transflag++; 2748 } 2749 if (nbuf[0] == '.' && nbuf[1] == '/') 2750 fprintf(dout, "%s%s\n", &nbuf[2], 2751 type == TYPE_A ? "\r" : ""); 2752 else 2753 fprintf(dout, "%s%s\n", nbuf, 2754 type == TYPE_A ? "\r" : ""); 2755 byte_count += strlen(nbuf) + 1; 2756 } 2757 } 2758 (void) closedir(dirp); 2759 } 2760 2761 if (dout == NULL) 2762 reply(550, "No files found."); 2763 else if (ferror(dout) != 0) 2764 perror_reply(550, "Data connection"); 2765 else 2766 reply(226, "Transfer complete."); 2767 2768 transflag = 0; 2769 if (dout != NULL) 2770 (void) fclose(dout); 2771 else { 2772 if (pdata >= 0) 2773 close(pdata); 2774 } 2775 data = -1; 2776 pdata = -1; 2777out: 2778 if (freeglob) { 2779 freeglob = 0; 2780 globfree(&gl); 2781 } 2782} 2783 2784/*ARGSUSED*/ 2785static void 2786reapchild(int signo) 2787{ 2788 int save_errno = errno; 2789 int rval; 2790 2791 do { 2792 rval = waitpid(-1, NULL, WNOHANG); 2793 } while (rval > 0 || (rval == -1 && errno == EINTR)); 2794 errno = save_errno; 2795} 2796 2797void 2798logxfer(char *name, off_t size, time_t start) 2799{ 2800 char buf[400 + (HOST_NAME_MAX+1)*4 + PATH_MAX*4]; 2801 char dir[PATH_MAX], path[PATH_MAX], rpath[PATH_MAX]; 2802 char vremotehost[(HOST_NAME_MAX+1)*4], vpath[PATH_MAX*4]; 2803 char *vpw; 2804 time_t now; 2805 int len; 2806 2807 if ((statfd >= 0) && (getcwd(dir, sizeof(dir)) != NULL)) { 2808 time(&now); 2809 2810 vpw = malloc(strlen(guest ? guestpw : pw->pw_name) * 4 + 1); 2811 if (vpw == NULL) 2812 return; 2813 2814 snprintf(path, sizeof(path), "%s/%s", dir, name); 2815 if (realpath(path, rpath) == NULL) 2816 strlcpy(rpath, path, sizeof(rpath)); 2817 strvis(vpath, rpath, VIS_SAFE|VIS_NOSLASH); 2818 2819 strvis(vremotehost, remotehost, VIS_SAFE|VIS_NOSLASH); 2820 strvis(vpw, guest? guestpw : pw->pw_name, VIS_SAFE|VIS_NOSLASH); 2821 2822 len = snprintf(buf, sizeof(buf), 2823 "%.24s %lld %s %qd %s %c %s %c %c %s ftp %d %s %s\n", 2824 ctime(&now), (long long)(now - start + (now == start)), 2825 vremotehost, (long long)size, vpath, 2826 ((type == TYPE_A) ? 'a' : 'b'), "*" /* none yet */, 2827 'o', ((guest) ? 'a' : 'r'), 2828 vpw, 0 /* none yet */, 2829 ((guest) ? "*" : pw->pw_name), dhostname); 2830 free(vpw); 2831 2832 if (len >= sizeof(buf) || len == -1) { 2833 if ((len = strlen(buf)) == 0) 2834 return; /* should not happen */ 2835 buf[len - 1] = '\n'; 2836 } 2837 write(statfd, buf, len); 2838 } 2839} 2840 2841void 2842set_slave_signals(void) 2843{ 2844 struct sigaction sa; 2845 2846 sigemptyset(&sa.sa_mask); 2847 sa.sa_flags = SA_RESTART; 2848 2849 sa.sa_handler = SIG_DFL; 2850 (void) sigaction(SIGCHLD, &sa, NULL); 2851 2852 sa.sa_handler = sigurg; 2853 sa.sa_flags = 0; /* don't restart syscalls for SIGURG */ 2854 (void) sigaction(SIGURG, &sa, NULL); 2855 2856 sigfillset(&sa.sa_mask); /* block all signals in handler */ 2857 sa.sa_flags = SA_RESTART; 2858 sa.sa_handler = sigquit; 2859 (void) sigaction(SIGHUP, &sa, NULL); 2860 (void) sigaction(SIGINT, &sa, NULL); 2861 (void) sigaction(SIGQUIT, &sa, NULL); 2862 (void) sigaction(SIGTERM, &sa, NULL); 2863 2864 sa.sa_handler = lostconn; 2865 (void) sigaction(SIGPIPE, &sa, NULL); 2866 2867 sa.sa_handler = toolong; 2868 (void) sigaction(SIGALRM, &sa, NULL); 2869 2870#ifdef F_SETOWN 2871 if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1) 2872 syslog(LOG_ERR, "fcntl F_SETOWN: %m"); 2873#endif 2874} 2875 2876/* 2877 * Allocate space and return a copy of the specified dir. 2878 * If 'dir' begins with a tilde (~), expand it. 2879 */ 2880char * 2881copy_dir(char *dir, struct passwd *pw) 2882{ 2883 char *cp; 2884 char *newdir; 2885 char *user = NULL; 2886 2887 /* Nothing to expand */ 2888 if (dir[0] != '~') 2889 return (strdup(dir)); 2890 2891 /* "dir" is of form ~user/some/dir, lookup user. */ 2892 if (dir[1] != '/' && dir[1] != '\0') { 2893 if ((cp = strchr(dir + 1, '/')) == NULL) 2894 cp = dir + strlen(dir); 2895 if ((user = malloc((size_t)(cp - dir))) == NULL) 2896 return (NULL); 2897 strlcpy(user, dir + 1, (size_t)(cp - dir)); 2898 2899 /* Only do lookup if it is a different user. */ 2900 if (strcmp(user, pw->pw_name) != 0) { 2901 if ((pw = getpwnam(user)) == NULL) { 2902 /* No such user, interpret literally */ 2903 free(user); 2904 return(strdup(dir)); 2905 } 2906 } 2907 free(user); 2908 } 2909 2910 /* 2911 * If there is no directory separator (/) then it is just pw_dir. 2912 * Otherwise, replace ~foo with pw_dir. 2913 */ 2914 if ((cp = strchr(dir + 1, '/')) == NULL) { 2915 newdir = strdup(pw->pw_dir); 2916 } else { 2917 if (asprintf(&newdir, "%s%s", pw->pw_dir, cp) == -1) 2918 return (NULL); 2919 } 2920 2921 return(newdir); 2922} 2923