1 /* $OpenBSD: ftpd.c,v 1.145 2003/07/29 18:39:22 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 #ifndef lint 63 static const char copyright[] = 64 "@(#) Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994\n\ 65 The Regents of the University of California. All rights reserved.\n"; 66 #endif /* not lint */ 67 68 #ifndef lint 69 #if 0 70 static const char sccsid[] = "@(#)ftpd.c 8.4 (Berkeley) 4/16/94"; 71 #else 72 static const char rcsid[] = 73 "$OpenBSD: ftpd.c,v 1.145 2003/07/29 18:39:22 deraadt Exp $"; 74 #endif 75 #endif /* not lint */ 76 77 /* 78 * FTP server. 79 */ 80 #include <sys/param.h> 81 #include <sys/stat.h> 82 #include <sys/ioctl.h> 83 #include <sys/socket.h> 84 #include <sys/wait.h> 85 #include <sys/mman.h> 86 87 #include <netinet/in.h> 88 #include <netinet/in_systm.h> 89 #include <netinet/ip.h> 90 #include <netinet/tcp.h> 91 92 #define FTP_NAMES 93 #include <arpa/ftp.h> 94 #include <arpa/inet.h> 95 #include <arpa/telnet.h> 96 97 #include <bsd_auth.h> 98 #include <ctype.h> 99 #include <dirent.h> 100 #include <err.h> 101 #include <errno.h> 102 #include <fcntl.h> 103 #include <glob.h> 104 #include <limits.h> 105 #include <login_cap.h> 106 #include <netdb.h> 107 #include <pwd.h> 108 #include <signal.h> 109 #include <stdarg.h> 110 #include <stdio.h> 111 #include <stdlib.h> 112 #include <string.h> 113 #include <syslog.h> 114 #include <time.h> 115 #include <vis.h> 116 #include <unistd.h> 117 #include <util.h> 118 #include <utmp.h> 119 120 #if defined(TCPWRAPPERS) 121 #include <tcpd.h> 122 #endif /* TCPWRAPPERS */ 123 124 #include "pathnames.h" 125 #include "extern.h" 126 127 static char version[] = "Version 6.5/OpenBSD"; 128 129 extern off_t restart_point; 130 extern char cbuf[]; 131 132 union sockunion server_addr; 133 union sockunion ctrl_addr; 134 union sockunion data_source; 135 union sockunion data_dest; 136 union sockunion his_addr; 137 union sockunion pasv_addr; 138 139 sigset_t allsigs; 140 141 int daemon_mode = 0; 142 int data; 143 int logged_in; 144 struct passwd *pw; 145 int debug = 0; 146 int timeout = 900; /* timeout after 15 minutes of inactivity */ 147 int maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */ 148 int logging; 149 int anon_ok = 1; 150 int anon_only = 0; 151 int multihome = 0; 152 int guest; 153 int stats; 154 int statfd = -1; 155 int portcheck = 1; 156 int dochroot; 157 int type; 158 int form; 159 int stru; /* avoid C keyword */ 160 int mode; 161 int doutmp = 0; /* update utmp file */ 162 int usedefault = 1; /* for data transfers */ 163 int pdata = -1; /* for passive mode */ 164 int family = AF_INET; 165 volatile sig_atomic_t transflag; 166 off_t file_size; 167 off_t byte_count; 168 #if !defined(CMASK) || CMASK == 0 169 #undef CMASK 170 #define CMASK 022 171 #endif 172 int defumask = CMASK; /* default umask value */ 173 int umaskchange = 1; /* allow user to change umask value. */ 174 char tmpline[7]; 175 char hostname[MAXHOSTNAMELEN]; 176 char remotehost[MAXHOSTNAMELEN]; 177 char dhostname[MAXHOSTNAMELEN]; 178 char *guestpw; 179 static char ttyline[20]; 180 char *tty = ttyline; /* for klogin */ 181 static struct utmp utmp; /* for utmp */ 182 static login_cap_t *lc; 183 static auth_session_t *as; 184 static volatile sig_atomic_t recvurg; 185 186 #if defined(TCPWRAPPERS) 187 int allow_severity = LOG_INFO; 188 int deny_severity = LOG_NOTICE; 189 #endif /* TCPWRAPPERS */ 190 191 char *ident = NULL; 192 193 194 int epsvall = 0; 195 196 /* 197 * Timeout intervals for retrying connections 198 * to hosts that don't accept PORT cmds. This 199 * is a kludge, but given the problems with TCP... 200 */ 201 #define SWAITMAX 90 /* wait at most 90 seconds */ 202 #define SWAITINT 5 /* interval between retries */ 203 204 int swaitmax = SWAITMAX; 205 int swaitint = SWAITINT; 206 207 #ifdef HASSETPROCTITLE 208 char proctitle[BUFSIZ]; /* initial part of title */ 209 #endif /* HASSETPROCTITLE */ 210 211 #define LOGCMD(cmd, file) \ 212 if (logging > 1) \ 213 syslog(LOG_INFO,"%s %s%s", cmd, \ 214 *(file) == '/' ? "" : curdir(), file); 215 #define LOGCMD2(cmd, file1, file2) \ 216 if (logging > 1) \ 217 syslog(LOG_INFO,"%s %s%s %s%s", cmd, \ 218 *(file1) == '/' ? "" : curdir(), file1, \ 219 *(file2) == '/' ? "" : curdir(), file2); 220 #define LOGBYTES(cmd, file, cnt) \ 221 if (logging > 1) { \ 222 if (cnt == (off_t)-1) \ 223 syslog(LOG_INFO,"%s %s%s", cmd, \ 224 *(file) == '/' ? "" : curdir(), file); \ 225 else \ 226 syslog(LOG_INFO, "%s %s%s = %qd bytes", \ 227 cmd, (*(file) == '/') ? "" : curdir(), file, cnt); \ 228 } 229 230 static void ack(char *); 231 static void sigurg(int); 232 static void myoob(void); 233 static int checkuser(char *, char *); 234 static FILE *dataconn(char *, off_t, char *); 235 static void dolog(struct sockaddr *); 236 static char *copy_dir(char *, struct passwd *); 237 static char *curdir(void); 238 static void end_login(void); 239 static FILE *getdatasock(char *); 240 static int guniquefd(char *, char **); 241 static void lostconn(int); 242 static void sigquit(int); 243 static int receive_data(FILE *, FILE *); 244 static void replydirname(const char *, const char *); 245 static int send_data(FILE *, FILE *, off_t, off_t, int); 246 static struct passwd * 247 sgetpwnam(char *, struct passwd *); 248 static void reapchild(int); 249 #if defined(TCPWRAPPERS) 250 static int check_host(struct sockaddr *); 251 #endif /* TCPWRAPPERS */ 252 static void usage(void); 253 254 void logxfer(char *, off_t, time_t); 255 256 static char * 257 curdir(void) 258 { 259 static char path[MAXPATHLEN+1]; /* path + '/' */ 260 261 if (getcwd(path, sizeof(path)-1) == NULL) 262 return (""); 263 if (path[1] != '\0') /* special case for root dir. */ 264 strlcat(path, "/", sizeof path); 265 /* For guest account, skip / since it's chrooted */ 266 return (guest ? path+1 : path); 267 } 268 269 char *argstr = "AdDhnlMSt:T:u:UvP46"; 270 271 static void 272 usage(void) 273 { 274 syslog(LOG_ERR, 275 "usage: ftpd [-AdDhlMPSU46] [-t timeout] [-T maxtimeout] [-u mask]"); 276 exit(2); 277 } 278 279 int 280 main(int argc, char *argv[]) 281 { 282 socklen_t addrlen; 283 int ch, on = 1, tos; 284 char *cp, line[LINE_MAX]; 285 FILE *fp; 286 struct hostent *hp; 287 struct sigaction sa; 288 289 tzset(); /* in case no timezone database in ~ftp */ 290 sigfillset(&allsigs); /* used to block signals while root */ 291 sigemptyset(&sa.sa_mask); 292 sa.sa_flags = SA_RESTART; 293 294 while ((ch = getopt(argc, argv, argstr)) != -1) { 295 switch (ch) { 296 case 'A': 297 anon_only = 1; 298 break; 299 300 case 'd': 301 case 'v': /* deprecated */ 302 debug = 1; 303 break; 304 305 case 'D': 306 daemon_mode = 1; 307 break; 308 309 case 'P': 310 portcheck = 0; 311 break; 312 313 case 'h': /* deprecated */ 314 break; 315 316 case 'l': 317 logging++; /* > 1 == extra logging */ 318 break; 319 320 case 'M': 321 multihome = 1; 322 break; 323 324 case 'n': 325 anon_ok = 0; 326 break; 327 328 case 'S': 329 stats = 1; 330 break; 331 332 case 't': 333 timeout = atoi(optarg); 334 if (maxtimeout < timeout) 335 maxtimeout = timeout; 336 break; 337 338 case 'T': 339 maxtimeout = atoi(optarg); 340 if (timeout > maxtimeout) 341 timeout = maxtimeout; 342 break; 343 344 case 'u': 345 { 346 long val = 0; 347 char *p; 348 umaskchange = 0; 349 350 val = strtol(optarg, &p, 8); 351 if (*p != '\0' || val < 0 || (val & ~ACCESSPERMS)) { 352 syslog(LOG_ERR, 353 "ftpd: %s is a bad value for -u, aborting..", 354 optarg); 355 exit(2); 356 } else 357 defumask = val; 358 break; 359 } 360 361 case 'U': 362 doutmp = 1; 363 break; 364 365 case '4': 366 family = AF_INET; 367 break; 368 369 case '6': 370 family = AF_INET6; 371 break; 372 373 default: 374 usage(); 375 break; 376 } 377 } 378 379 (void) freopen(_PATH_DEVNULL, "w", stderr); 380 381 /* 382 * LOG_NDELAY sets up the logging connection immediately, 383 * necessary for anonymous ftp's that chroot and can't do it later. 384 */ 385 openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP); 386 387 if (daemon_mode) { 388 int ctl_sock, fd; 389 struct servent *sv; 390 391 /* 392 * Detach from parent. 393 */ 394 if (daemon(1, 1) < 0) { 395 syslog(LOG_ERR, "failed to become a daemon"); 396 exit(1); 397 } 398 sa.sa_handler = reapchild; 399 (void) sigaction(SIGCHLD, &sa, NULL); 400 /* 401 * Get port number for ftp/tcp. 402 */ 403 sv = getservbyname("ftp", "tcp"); 404 if (sv == NULL) { 405 syslog(LOG_ERR, "getservbyname for ftp failed"); 406 exit(1); 407 } 408 /* 409 * Open a socket, bind it to the FTP port, and start 410 * listening. 411 */ 412 ctl_sock = socket(family, SOCK_STREAM, 0); 413 if (ctl_sock < 0) { 414 syslog(LOG_ERR, "control socket: %m"); 415 exit(1); 416 } 417 if (setsockopt(ctl_sock, SOL_SOCKET, SO_REUSEADDR, 418 (char *)&on, sizeof(on)) < 0) 419 syslog(LOG_ERR, "control setsockopt: %m"); 420 memset(&server_addr, 0, sizeof(server_addr)); 421 server_addr.su_sin.sin_family = family; 422 switch (family) { 423 case AF_INET: 424 server_addr.su_len = sizeof(struct sockaddr_in); 425 server_addr.su_sin.sin_port = sv->s_port; 426 break; 427 case AF_INET6: 428 server_addr.su_len = sizeof(struct sockaddr_in6); 429 server_addr.su_sin6.sin6_port = sv->s_port; 430 break; 431 } 432 if (bind(ctl_sock, (struct sockaddr *)&server_addr, 433 server_addr.su_len)) { 434 syslog(LOG_ERR, "control bind: %m"); 435 exit(1); 436 } 437 if (listen(ctl_sock, 32) < 0) { 438 syslog(LOG_ERR, "control listen: %m"); 439 exit(1); 440 } 441 /* Stash pid in pidfile */ 442 if (pidfile(NULL)) 443 syslog(LOG_ERR, "can't open pidfile: %m"); 444 /* 445 * Loop forever accepting connection requests and forking off 446 * children to handle them. 447 */ 448 while (1) { 449 addrlen = sizeof(his_addr); 450 fd = accept(ctl_sock, (struct sockaddr *)&his_addr, 451 &addrlen); 452 if (fork() == 0) { 453 /* child */ 454 (void) dup2(fd, 0); 455 (void) dup2(fd, 1); 456 close(ctl_sock); 457 break; 458 } 459 close(fd); 460 } 461 462 #if defined(TCPWRAPPERS) 463 /* ..in the child. */ 464 if (!check_host((struct sockaddr *)&his_addr)) 465 exit(1); 466 #endif /* TCPWRAPPERS */ 467 } else { 468 addrlen = sizeof(his_addr); 469 if (getpeername(0, (struct sockaddr *)&his_addr, 470 &addrlen) < 0) { 471 /* syslog(LOG_ERR, "getpeername (%s): %m", argv[0]); */ 472 exit(1); 473 } 474 } 475 476 /* set this here so klogin can use it... */ 477 (void)snprintf(ttyline, sizeof(ttyline), "ftp%ld", (long)getpid()); 478 479 sa.sa_handler = SIG_DFL; 480 (void) sigaction(SIGCHLD, &sa, NULL); 481 482 sa.sa_handler = sigurg; 483 sa.sa_flags = 0; /* don't restart syscalls for SIGURG */ 484 (void) sigaction(SIGURG, &sa, NULL); 485 486 sigfillset(&sa.sa_mask); /* block all signals in handler */ 487 sa.sa_flags = SA_RESTART; 488 sa.sa_handler = sigquit; 489 (void) sigaction(SIGHUP, &sa, NULL); 490 (void) sigaction(SIGINT, &sa, NULL); 491 (void) sigaction(SIGQUIT, &sa, NULL); 492 (void) sigaction(SIGTERM, &sa, NULL); 493 494 sa.sa_handler = lostconn; 495 (void) sigaction(SIGPIPE, &sa, NULL); 496 497 sa.sa_handler = toolong; 498 (void) sigaction(SIGALRM, &sa, NULL); 499 500 addrlen = sizeof(ctrl_addr); 501 if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) { 502 syslog(LOG_ERR, "getsockname: %m"); 503 exit(1); 504 } 505 if (his_addr.su_family == AF_INET6 506 && IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr)) { 507 #if 1 508 /* 509 * IPv4 control connection arrived to AF_INET6 socket. 510 * I hate to do this, but this is the easiest solution. 511 */ 512 union sockunion tmp_addr; 513 const int off = sizeof(struct in6_addr) - sizeof(struct in_addr); 514 515 tmp_addr = his_addr; 516 memset(&his_addr, 0, sizeof(his_addr)); 517 his_addr.su_sin.sin_family = AF_INET; 518 his_addr.su_sin.sin_len = sizeof(his_addr.su_sin); 519 memcpy(&his_addr.su_sin.sin_addr, 520 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 521 sizeof(his_addr.su_sin.sin_addr)); 522 his_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 523 524 tmp_addr = ctrl_addr; 525 memset(&ctrl_addr, 0, sizeof(ctrl_addr)); 526 ctrl_addr.su_sin.sin_family = AF_INET; 527 ctrl_addr.su_sin.sin_len = sizeof(ctrl_addr.su_sin); 528 memcpy(&ctrl_addr.su_sin.sin_addr, 529 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 530 sizeof(ctrl_addr.su_sin.sin_addr)); 531 ctrl_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 532 #else 533 while (fgets(line, sizeof(line), fd) != NULL) { 534 if ((cp = strchr(line, '\n')) != NULL) 535 *cp = '\0'; 536 lreply(530, "%s", line); 537 } 538 (void) fflush(stdout); 539 (void) fclose(fd); 540 reply(530, 541 "Connection from IPv4 mapped address is not supported."); 542 exit(0); 543 #endif 544 } 545 #ifdef IP_TOS 546 if (his_addr.su_family == AF_INET) { 547 tos = IPTOS_LOWDELAY; 548 if (setsockopt(0, IPPROTO_IP, IP_TOS, (char *)&tos, 549 sizeof(int)) < 0) 550 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 551 } 552 #endif 553 data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1); 554 555 /* Try to handle urgent data inline */ 556 #ifdef SO_OOBINLINE 557 if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, (char *)&on, sizeof(on)) < 0) 558 syslog(LOG_ERR, "setsockopt: %m"); 559 #endif 560 561 #ifdef F_SETOWN 562 if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1) 563 syslog(LOG_ERR, "fcntl F_SETOWN: %m"); 564 #endif 565 dolog((struct sockaddr *)&his_addr); 566 /* 567 * Set up default state 568 */ 569 data = -1; 570 type = TYPE_A; 571 form = FORM_N; 572 stru = STRU_F; 573 mode = MODE_S; 574 tmpline[0] = '\0'; 575 576 /* If logins are disabled, print out the message. */ 577 if ((fp = fopen(_PATH_NOLOGIN, "r")) != NULL) { 578 while (fgets(line, sizeof(line), fp) != NULL) { 579 if ((cp = strchr(line, '\n')) != NULL) 580 *cp = '\0'; 581 lreply(530, "%s", line); 582 } 583 (void) fflush(stdout); 584 (void) fclose(fp); 585 reply(530, "System not available."); 586 exit(0); 587 } 588 if ((fp = fopen(_PATH_FTPWELCOME, "r")) != NULL) { 589 while (fgets(line, sizeof(line), fp) != NULL) { 590 if ((cp = strchr(line, '\n')) != NULL) 591 *cp = '\0'; 592 lreply(220, "%s", line); 593 } 594 (void) fflush(stdout); 595 (void) fclose(fp); 596 /* reply(220,) must follow */ 597 } 598 (void) gethostname(hostname, sizeof(hostname)); 599 600 /* Make sure hostname is fully qualified. */ 601 hp = gethostbyname(hostname); 602 if (hp != NULL) 603 strlcpy(hostname, hp->h_name, sizeof(hostname)); 604 605 if (multihome) { 606 getnameinfo((struct sockaddr *)&ctrl_addr, ctrl_addr.su_len, 607 dhostname, sizeof(dhostname), NULL, 0, 0); 608 } 609 610 reply(220, "%s FTP server (%s) ready.", 611 (multihome ? dhostname : hostname), version); 612 for (;;) 613 (void) yyparse(); 614 /* NOTREACHED */ 615 } 616 617 /* 618 * Signal handlers. 619 */ 620 621 static void 622 lostconn(int signo) 623 { 624 struct syslog_data sdata = SYSLOG_DATA_INIT; 625 626 if (debug) 627 syslog_r(LOG_DEBUG, &sdata, "lost connection"); 628 dologout(1); 629 } 630 631 static void 632 sigquit(int signo) 633 { 634 struct syslog_data sdata = SYSLOG_DATA_INIT; 635 636 syslog_r(LOG_ERR, &sdata, "got signal %s", sys_signame[signo]); 637 dologout(1); 638 } 639 640 /* 641 * Save the result of a getpwnam. Used for USER command, since 642 * the data returned must not be clobbered by any other command 643 * (e.g., globbing). 644 */ 645 static struct passwd * 646 sgetpwnam(char *name, struct passwd *pw) 647 { 648 static struct passwd *save; 649 struct passwd *old; 650 651 if (pw == NULL && (pw = getpwnam(name)) == NULL) 652 return (NULL); 653 old = save; 654 save = pw_dup(pw); 655 if (save == NULL) { 656 perror_reply(421, "Local resource failure: malloc"); 657 dologout(1); 658 /* NOTREACHED */ 659 } 660 if (old) { 661 memset(old->pw_passwd, 0, strlen(old->pw_passwd)); 662 free(old); 663 } 664 return (save); 665 } 666 667 static int login_attempts; /* number of failed login attempts */ 668 static int askpasswd; /* had user command, ask for passwd */ 669 static char curname[MAXLOGNAME]; /* current USER name */ 670 671 /* 672 * USER command. 673 * Sets global passwd pointer pw if named account exists and is acceptable; 674 * sets askpasswd if a PASS command is expected. If logged in previously, 675 * need to reset state. If name is "ftp" or "anonymous", the name is not in 676 * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return. 677 * If account doesn't exist, ask for passwd anyway. Otherwise, check user 678 * requesting login privileges. Disallow anyone who does not have a standard 679 * shell as returned by getusershell(). Disallow anyone mentioned in the file 680 * _PATH_FTPUSERS to allow people such as root and uucp to be avoided. 681 */ 682 void 683 user(char *name) 684 { 685 char *cp, *shell, *style, *host; 686 char *class = NULL; 687 688 if (logged_in) 689 end_login(); 690 691 /* Close session from previous user if there was one. */ 692 if (as) { 693 auth_close(as); 694 as = NULL; 695 } 696 if (lc) { 697 login_close(lc); 698 lc = NULL; 699 } 700 701 if ((style = strchr(name, ':')) != NULL) 702 *style++ = 0; 703 704 guest = 0; 705 host = multihome ? dhostname : hostname; 706 if (anon_ok && 707 (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0)) { 708 if (checkuser(_PATH_FTPUSERS, "ftp") || 709 checkuser(_PATH_FTPUSERS, "anonymous")) 710 reply(530, "User %s access denied.", name); 711 else if ((pw = sgetpwnam("ftp", NULL)) != NULL) { 712 guest = 1; 713 askpasswd = 1; 714 lc = login_getclass(pw->pw_class); 715 if ((as = auth_open()) == NULL || 716 auth_setpwd(as, pw) != 0 || 717 auth_setoption(as, "FTPD_HOST", host) < 0) { 718 if (as) { 719 auth_close(as); 720 as = NULL; 721 } 722 login_close(lc); 723 lc = NULL; 724 reply(421, "Local resource failure"); 725 return; 726 } 727 reply(331, 728 "Guest login ok, send your email address as password."); 729 } else 730 reply(530, "User %s unknown.", name); 731 if (!askpasswd && logging) 732 syslog(LOG_NOTICE, 733 "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost); 734 return; 735 } 736 737 shell = _PATH_BSHELL; 738 if ((pw = sgetpwnam(name, NULL))) { 739 class = pw->pw_class; 740 if (pw->pw_shell != NULL && *pw->pw_shell != '\0') 741 shell = pw->pw_shell; 742 while ((cp = getusershell()) != NULL) 743 if (strcmp(cp, shell) == 0) 744 break; 745 shell = cp; 746 endusershell(); 747 } 748 749 /* Get login class; if invalid style treat like unknown user. */ 750 lc = login_getclass(class); 751 if (lc && (style = login_getstyle(lc, style, "auth-ftp")) == NULL) { 752 login_close(lc); 753 lc = NULL; 754 pw = NULL; 755 } 756 757 /* Do pre-authentication setup. */ 758 if (lc && ((as = auth_open()) == NULL || 759 (pw != NULL && auth_setpwd(as, pw) != 0) || 760 auth_setitem(as, AUTHV_STYLE, style) < 0 || 761 auth_setitem(as, AUTHV_NAME, name) < 0 || 762 auth_setitem(as, AUTHV_CLASS, class) < 0 || 763 auth_setoption(as, "login", "yes") < 0 || 764 auth_setoption(as, "notickets", "yes") < 0 || 765 auth_setoption(as, "FTPD_HOST", host) < 0)) { 766 if (as) { 767 auth_close(as); 768 as = NULL; 769 } 770 login_close(lc); 771 lc = NULL; 772 reply(421, "Local resource failure"); 773 return; 774 } 775 if (logging) 776 strlcpy(curname, name, sizeof(curname)); 777 778 dochroot = (lc && login_getcapbool(lc, "ftp-chroot", 0)) || 779 checkuser(_PATH_FTPCHROOT, name); 780 if (anon_only && !dochroot) { 781 reply(530, "Sorry, only anonymous ftp allowed."); 782 return; 783 } 784 if (pw) { 785 if ((!shell && !dochroot) || checkuser(_PATH_FTPUSERS, name)) { 786 reply(530, "User %s access denied.", name); 787 if (logging) 788 syslog(LOG_NOTICE, 789 "FTP LOGIN REFUSED FROM %s, %s", 790 remotehost, name); 791 pw = NULL; 792 return; 793 } 794 } 795 796 if (as != NULL && (cp = auth_challenge(as)) != NULL) 797 reply(331, "%s", cp); 798 else 799 reply(331, "Password required for %s.", name); 800 801 askpasswd = 1; 802 /* 803 * Delay before reading passwd after first failed 804 * attempt to slow down passwd-guessing programs. 805 */ 806 if (login_attempts) 807 sleep((unsigned) login_attempts); 808 } 809 810 /* 811 * Check if a user is in the file "fname" 812 */ 813 static int 814 checkuser(char *fname, char *name) 815 { 816 FILE *fp; 817 int found = 0; 818 char *p, line[BUFSIZ]; 819 820 if ((fp = fopen(fname, "r")) != NULL) { 821 while (fgets(line, sizeof(line), fp) != NULL) 822 if ((p = strchr(line, '\n')) != NULL) { 823 *p = '\0'; 824 if (line[0] == '#') 825 continue; 826 if (strcmp(line, name) == 0) { 827 found = 1; 828 break; 829 } 830 } 831 (void) fclose(fp); 832 } 833 return (found); 834 } 835 836 /* 837 * Terminate login as previous user, if any, resetting state; 838 * used when USER command is given or login fails. 839 */ 840 static void 841 end_login(void) 842 { 843 844 sigprocmask (SIG_BLOCK, &allsigs, NULL); 845 if (logged_in) { 846 ftpdlogwtmp(ttyline, "", ""); 847 if (doutmp) 848 ftpd_logout(utmp.ut_line); 849 } 850 reply(530, "Please reconnect to work as another user"); 851 exit(0); 852 } 853 854 void 855 pass(char *passwd) 856 { 857 int authok, flags; 858 FILE *fp; 859 static char homedir[MAXPATHLEN]; 860 char *motd, *dir, rootdir[MAXPATHLEN]; 861 size_t sz_pw_dir; 862 863 if (logged_in || askpasswd == 0) { 864 reply(503, "Login with USER first."); 865 return; 866 } 867 askpasswd = 0; 868 if (!guest) { /* "ftp" is only account allowed no password */ 869 authok = 0; 870 if (pw == NULL || pw->pw_passwd[0] == '\0') { 871 useconds_t us; 872 873 /* Sleep between 1 and 3 seconds to emulate a crypt. */ 874 us = arc4random() % 3000000; 875 usleep(us); 876 if (as != NULL) { 877 auth_close(as); 878 as = NULL; 879 } 880 } else { 881 authok = auth_userresponse(as, passwd, 0); 882 as = NULL; 883 } 884 if (authok == 0) { 885 reply(530, "Login incorrect."); 886 if (logging) 887 syslog(LOG_NOTICE, 888 "FTP LOGIN FAILED FROM %s, %s", 889 remotehost, curname); 890 pw = NULL; 891 if (login_attempts++ >= 5) { 892 syslog(LOG_NOTICE, 893 "repeated login failures from %s", 894 remotehost); 895 exit(0); 896 } 897 return; 898 } 899 } else if (lc != NULL) { 900 /* Save anonymous' password. */ 901 if (guestpw != NULL) 902 free(guestpw); 903 guestpw = strdup(passwd); 904 if (guestpw == NULL) 905 fatal("Out of memory."); 906 907 authok = auth_approval(as, lc, pw->pw_name, "ftp"); 908 auth_close(as); 909 as = NULL; 910 if (authok == 0) { 911 syslog(LOG_INFO|LOG_AUTH, 912 "FTP LOGIN FAILED (HOST) as %s: approval failure.", 913 pw->pw_name); 914 reply(530, "Approval failure."); 915 exit(0); 916 } 917 } else { 918 syslog(LOG_INFO|LOG_AUTH, 919 "FTP LOGIN CLASS %s MISSING for %s: approval failure.", 920 pw->pw_class, pw->pw_name); 921 reply(530, "Permission denied."); 922 exit(0); 923 } 924 login_attempts = 0; /* this time successful */ 925 /* set umask via setusercontext() unless -u flag was given. */ 926 flags = LOGIN_SETGROUP|LOGIN_SETPRIORITY|LOGIN_SETRESOURCES; 927 if (umaskchange) 928 flags |= LOGIN_SETUMASK; 929 else 930 (void) umask(defumask); 931 if (setusercontext(lc, pw, (uid_t)0, flags) != 0) { 932 perror_reply(451, "Local resource failure: setusercontext"); 933 syslog(LOG_NOTICE, "setusercontext: %m"); 934 dologout(1); 935 /* NOTREACHED */ 936 } 937 938 /* open wtmp before chroot */ 939 ftpdlogwtmp(ttyline, pw->pw_name, remotehost); 940 941 /* open utmp before chroot */ 942 if (doutmp) { 943 memset((void *)&utmp, 0, sizeof(utmp)); 944 (void)time(&utmp.ut_time); 945 (void)strncpy(utmp.ut_name, pw->pw_name, sizeof(utmp.ut_name)); 946 (void)strncpy(utmp.ut_host, remotehost, sizeof(utmp.ut_host)); 947 (void)strncpy(utmp.ut_line, ttyline, sizeof(utmp.ut_line)); 948 ftpd_login(&utmp); 949 } 950 951 /* open stats file before chroot */ 952 if (guest && (stats == 1) && (statfd < 0)) 953 if ((statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND)) < 0) 954 stats = 0; 955 956 logged_in = 1; 957 958 if ((dir = login_getcapstr(lc, "ftp-dir", NULL, NULL))) { 959 char *newdir; 960 961 newdir = copy_dir(dir, pw); 962 if (newdir == NULL) { 963 perror_reply(421, "Local resource failure: malloc"); 964 dologout(1); 965 /* NOTREACHED */ 966 } 967 pw->pw_dir = newdir; 968 pw = sgetpwnam(NULL, pw); 969 free(dir); 970 free(newdir); 971 } 972 973 /* make sure pw->pw_dir is big enough to hold "/" */ 974 sz_pw_dir = strlen(pw->pw_dir) + 1; 975 if (sz_pw_dir < 2) { 976 pw->pw_dir = "/"; 977 pw = sgetpwnam(NULL, pw); 978 sz_pw_dir = 2; 979 } 980 981 if (guest || dochroot) { 982 if (multihome && guest) { 983 struct stat ts; 984 985 /* Compute root directory. */ 986 snprintf(rootdir, sizeof(rootdir), "%s/%s", 987 pw->pw_dir, dhostname); 988 if (stat(rootdir, &ts) < 0) { 989 snprintf(rootdir, sizeof(rootdir), "%s/%s", 990 pw->pw_dir, hostname); 991 } 992 } else 993 strlcpy(rootdir, pw->pw_dir, sizeof(rootdir)); 994 } 995 if (guest) { 996 /* 997 * We MUST do a chdir() after the chroot. Otherwise 998 * the old current directory will be accessible as "." 999 * outside the new root! 1000 */ 1001 if (chroot(rootdir) < 0 || chdir("/") < 0) { 1002 reply(550, "Can't set guest privileges."); 1003 goto bad; 1004 } 1005 strlcpy(pw->pw_dir, "/", sz_pw_dir); 1006 if (setenv("HOME", "/", 1) == -1) { 1007 reply(550, "Can't setup environment."); 1008 goto bad; 1009 } 1010 } else if (dochroot) { 1011 if (chroot(rootdir) < 0 || chdir("/") < 0) { 1012 reply(550, "Can't change root."); 1013 goto bad; 1014 } 1015 strlcpy(pw->pw_dir, "/", sz_pw_dir); 1016 if (setenv("HOME", "/", 1) == -1) { 1017 reply(550, "Can't setup environment."); 1018 goto bad; 1019 } 1020 } else if (chdir(pw->pw_dir) < 0) { 1021 if (chdir("/") < 0) { 1022 reply(530, "User %s: can't change directory to %s.", 1023 pw->pw_name, pw->pw_dir); 1024 goto bad; 1025 } else 1026 lreply(230, "No directory! Logging in with home=/"); 1027 } 1028 if (seteuid(pw->pw_uid) < 0) { 1029 reply(550, "Can't set uid."); 1030 goto bad; 1031 } 1032 sigprocmask(SIG_UNBLOCK, &allsigs, NULL); 1033 1034 /* 1035 * Set home directory so that use of ~ (tilde) works correctly. 1036 */ 1037 if (getcwd(homedir, MAXPATHLEN) != NULL) { 1038 if (setenv("HOME", homedir, 1) == -1) { 1039 reply(550, "Can't setup environment."); 1040 goto bad; 1041 } 1042 } 1043 1044 /* 1045 * Display a login message, if it exists. 1046 * N.B. reply(230,) must follow the message. 1047 */ 1048 motd = login_getcapstr(lc, "welcome", NULL, NULL); 1049 if ((fp = fopen(motd ? motd : _PATH_FTPLOGINMESG, "r")) != NULL) { 1050 char *cp, line[LINE_MAX]; 1051 1052 while (fgets(line, sizeof(line), fp) != NULL) { 1053 if ((cp = strchr(line, '\n')) != NULL) 1054 *cp = '\0'; 1055 lreply(230, "%s", line); 1056 } 1057 (void) fflush(stdout); 1058 (void) fclose(fp); 1059 } 1060 if (motd != NULL) 1061 free(motd); 1062 if (guest) { 1063 if (ident != NULL) 1064 free(ident); 1065 ident = strdup(passwd); 1066 if (ident == NULL) 1067 fatal("Ran out of memory."); 1068 reply(230, "Guest login ok, access restrictions apply."); 1069 #ifdef HASSETPROCTITLE 1070 snprintf(proctitle, sizeof(proctitle), 1071 "%s: anonymous/%.*s", remotehost, 1072 (int)(sizeof(proctitle) - sizeof(remotehost) - 1073 sizeof(": anonymous/")), passwd); 1074 setproctitle("%s", proctitle); 1075 #endif /* HASSETPROCTITLE */ 1076 if (logging) 1077 syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s", 1078 remotehost, passwd); 1079 } else { 1080 reply(230, "User %s logged in.", pw->pw_name); 1081 #ifdef HASSETPROCTITLE 1082 snprintf(proctitle, sizeof(proctitle), 1083 "%s: %s", remotehost, pw->pw_name); 1084 setproctitle("%s", proctitle); 1085 #endif /* HASSETPROCTITLE */ 1086 if (logging) 1087 syslog(LOG_INFO, "FTP LOGIN FROM %s as %s", 1088 remotehost, pw->pw_name); 1089 } 1090 login_close(lc); 1091 lc = NULL; 1092 return; 1093 bad: 1094 /* Forget all about it... */ 1095 login_close(lc); 1096 lc = NULL; 1097 end_login(); 1098 } 1099 1100 void 1101 retrieve(char *cmd, char *name) 1102 { 1103 FILE *fin, *dout; 1104 struct stat st; 1105 int (*closefunc)(FILE *); 1106 time_t start; 1107 1108 if (cmd == 0) { 1109 fin = fopen(name, "r"), closefunc = fclose; 1110 st.st_size = 0; 1111 } else { 1112 char line[BUFSIZ]; 1113 1114 (void) snprintf(line, sizeof(line), cmd, name); 1115 name = line; 1116 fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose; 1117 st.st_size = -1; 1118 st.st_blksize = BUFSIZ; 1119 } 1120 if (fin == NULL) { 1121 if (errno != 0) { 1122 perror_reply(550, name); 1123 if (cmd == 0) { 1124 LOGCMD("get", name); 1125 } 1126 } 1127 return; 1128 } 1129 byte_count = -1; 1130 if (cmd == 0 && (fstat(fileno(fin), &st) < 0 || !S_ISREG(st.st_mode))) { 1131 reply(550, "%s: not a plain file.", name); 1132 goto done; 1133 } 1134 if (restart_point) { 1135 if (type == TYPE_A) { 1136 off_t i, n; 1137 int c; 1138 1139 n = restart_point; 1140 i = 0; 1141 while (i++ < n) { 1142 if ((c=getc(fin)) == EOF) { 1143 perror_reply(550, name); 1144 goto done; 1145 } 1146 if (c == '\n') 1147 i++; 1148 } 1149 } else if (lseek(fileno(fin), restart_point, SEEK_SET) < 0) { 1150 perror_reply(550, name); 1151 goto done; 1152 } 1153 } 1154 dout = dataconn(name, st.st_size, "w"); 1155 if (dout == NULL) 1156 goto done; 1157 time(&start); 1158 send_data(fin, dout, st.st_blksize, st.st_size, 1159 (restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode))); 1160 if ((cmd == 0) && stats) 1161 logxfer(name, byte_count, start); 1162 (void) fclose(dout); 1163 data = -1; 1164 done: 1165 if (pdata >= 0) 1166 (void) close(pdata); 1167 pdata = -1; 1168 if (cmd == 0) 1169 LOGBYTES("get", name, byte_count); 1170 (*closefunc)(fin); 1171 } 1172 1173 void 1174 store(char *name, char *mode, int unique) 1175 { 1176 FILE *fout, *din; 1177 int (*closefunc)(FILE *); 1178 struct stat st; 1179 int fd; 1180 1181 if (restart_point && *mode != 'a') 1182 mode = "r+"; 1183 1184 if (unique && stat(name, &st) == 0) { 1185 char *nam; 1186 1187 fd = guniquefd(name, &nam); 1188 if (fd == -1) { 1189 LOGCMD(*mode == 'w' ? "put" : "append", name); 1190 return; 1191 } 1192 name = nam; 1193 fout = fdopen(fd, mode); 1194 } else 1195 fout = fopen(name, mode); 1196 1197 closefunc = fclose; 1198 if (fout == NULL) { 1199 perror_reply(553, name); 1200 LOGCMD(*mode == 'w' ? "put" : "append", name); 1201 return; 1202 } 1203 byte_count = -1; 1204 if (restart_point) { 1205 if (type == TYPE_A) { 1206 off_t i, n; 1207 int c; 1208 1209 n = restart_point; 1210 i = 0; 1211 while (i++ < n) { 1212 if ((c=getc(fout)) == EOF) { 1213 perror_reply(550, name); 1214 goto done; 1215 } 1216 if (c == '\n') 1217 i++; 1218 } 1219 /* 1220 * We must do this seek to "current" position 1221 * because we are changing from reading to 1222 * writing. 1223 */ 1224 if (fseek(fout, 0L, SEEK_CUR) < 0) { 1225 perror_reply(550, name); 1226 goto done; 1227 } 1228 } else if (lseek(fileno(fout), restart_point, SEEK_SET) < 0) { 1229 perror_reply(550, name); 1230 goto done; 1231 } 1232 } 1233 din = dataconn(name, (off_t)-1, "r"); 1234 if (din == NULL) 1235 goto done; 1236 if (receive_data(din, fout) == 0) { 1237 if (unique) 1238 reply(226, "Transfer complete (unique file name:%s).", 1239 name); 1240 else 1241 reply(226, "Transfer complete."); 1242 } 1243 (void) fclose(din); 1244 data = -1; 1245 pdata = -1; 1246 done: 1247 LOGBYTES(*mode == 'w' ? "put" : "append", name, byte_count); 1248 (*closefunc)(fout); 1249 } 1250 1251 static FILE * 1252 getdatasock(char *mode) 1253 { 1254 int on = 1, s, t, tries; 1255 1256 if (data >= 0) 1257 return (fdopen(data, mode)); 1258 sigprocmask (SIG_BLOCK, &allsigs, NULL); 1259 s = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 1260 if (s < 0) 1261 goto bad; 1262 if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, 1263 (char *) &on, sizeof(on)) < 0) 1264 goto bad; 1265 /* anchor socket to avoid multi-homing problems */ 1266 data_source = ctrl_addr; 1267 data_source.su_port = htons(20); /* ftp-data port */ 1268 (void) seteuid(0); 1269 for (tries = 1; ; tries++) { 1270 if (bind(s, (struct sockaddr *)&data_source, 1271 data_source.su_len) >= 0) 1272 break; 1273 if (errno != EADDRINUSE || tries > 10) { 1274 (void) seteuid(pw->pw_uid); 1275 goto bad; 1276 } 1277 sleep(tries); 1278 } 1279 (void) seteuid((uid_t)pw->pw_uid); 1280 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1281 1282 #ifdef IP_TOS 1283 if (ctrl_addr.su_family == AF_INET) { 1284 on = IPTOS_THROUGHPUT; 1285 if (setsockopt(s, IPPROTO_IP, IP_TOS, (char *)&on, 1286 sizeof(int)) < 0) 1287 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 1288 } 1289 #endif 1290 #ifdef TCP_NOPUSH 1291 /* 1292 * Turn off push flag to keep sender TCP from sending short packets 1293 * at the boundaries of each write(). Should probably do a SO_SNDBUF 1294 * to set the send buffer size as well, but that may not be desirable 1295 * in heavy-load situations. 1296 */ 1297 on = 1; 1298 if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, (char *)&on, sizeof(on)) < 0) 1299 syslog(LOG_WARNING, "setsockopt (TCP_NOPUSH): %m"); 1300 #endif 1301 #ifdef SO_SNDBUF 1302 on = 65536; 1303 if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, (char *)&on, sizeof(on)) < 0) 1304 syslog(LOG_WARNING, "setsockopt (SO_SNDBUF): %m"); 1305 #endif 1306 1307 return (fdopen(s, mode)); 1308 bad: 1309 /* Return the real value of errno (close may change it) */ 1310 t = errno; 1311 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1312 (void) close(s); 1313 errno = t; 1314 return (NULL); 1315 } 1316 1317 static FILE * 1318 dataconn(char *name, off_t size, char *mode) 1319 { 1320 char sizebuf[32]; 1321 FILE *file; 1322 int retry = 0; 1323 in_port_t *p; 1324 u_char *fa, *ha; 1325 int alen; 1326 1327 file_size = size; 1328 byte_count = 0; 1329 if (size != (off_t) -1) { 1330 (void) snprintf(sizebuf, sizeof(sizebuf), " (%qd bytes)", 1331 size); 1332 } else 1333 sizebuf[0] = '\0'; 1334 if (pdata >= 0) { 1335 union sockunion from; 1336 int s; 1337 socklen_t fromlen = sizeof(from); 1338 1339 (void) alarm ((unsigned) timeout); 1340 s = accept(pdata, (struct sockaddr *)&from, &fromlen); 1341 (void) alarm (0); 1342 if (s < 0) { 1343 reply(425, "Can't open data connection."); 1344 (void) close(pdata); 1345 pdata = -1; 1346 return (NULL); 1347 } 1348 switch (from.su_family) { 1349 case AF_INET: 1350 p = (in_port_t *)&from.su_sin.sin_port; 1351 fa = (u_char *)&from.su_sin.sin_addr; 1352 ha = (u_char *)&his_addr.su_sin.sin_addr; 1353 alen = sizeof(struct in_addr); 1354 break; 1355 case AF_INET6: 1356 p = (in_port_t *)&from.su_sin6.sin6_port; 1357 fa = (u_char *)&from.su_sin6.sin6_addr; 1358 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1359 alen = sizeof(struct in6_addr); 1360 break; 1361 default: 1362 perror_reply(425, "Can't build data connection"); 1363 (void) close(pdata); 1364 (void) close(s); 1365 pdata = -1; 1366 return (NULL); 1367 } 1368 if (from.su_family != his_addr.su_family || 1369 ntohs(*p) < IPPORT_RESERVED) { 1370 perror_reply(425, "Can't build data connection"); 1371 (void) close(pdata); 1372 (void) close(s); 1373 pdata = -1; 1374 return (NULL); 1375 } 1376 if (portcheck && memcmp(fa, ha, alen) != 0) { 1377 perror_reply(435, "Can't build data connection"); 1378 (void) close(pdata); 1379 (void) close(s); 1380 pdata = -1; 1381 return (NULL); 1382 } 1383 (void) close(pdata); 1384 pdata = s; 1385 reply(150, "Opening %s mode data connection for '%s'%s.", 1386 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1387 return (fdopen(pdata, mode)); 1388 } 1389 if (data >= 0) { 1390 reply(125, "Using existing data connection for '%s'%s.", 1391 name, sizebuf); 1392 usedefault = 1; 1393 return (fdopen(data, mode)); 1394 } 1395 if (usedefault) 1396 data_dest = his_addr; 1397 usedefault = 1; 1398 file = getdatasock(mode); 1399 if (file == NULL) { 1400 char hbuf[MAXHOSTNAMELEN], pbuf[10]; 1401 1402 getnameinfo((struct sockaddr *)&data_source, data_source.su_len, 1403 hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), 1404 NI_NUMERICHOST | NI_NUMERICSERV); 1405 reply(425, "Can't create data socket (%s,%s): %s.", 1406 hbuf, pbuf, strerror(errno)); 1407 return (NULL); 1408 } 1409 data = fileno(file); 1410 1411 /* 1412 * attempt to connect to reserved port on client machine; 1413 * this looks like an attack 1414 */ 1415 switch (data_dest.su_family) { 1416 case AF_INET: 1417 p = (in_port_t *)&data_dest.su_sin.sin_port; 1418 fa = (u_char *)&data_dest.su_sin.sin_addr; 1419 ha = (u_char *)&his_addr.su_sin.sin_addr; 1420 alen = sizeof(struct in_addr); 1421 break; 1422 case AF_INET6: 1423 p = (in_port_t *)&data_dest.su_sin6.sin6_port; 1424 fa = (u_char *)&data_dest.su_sin6.sin6_addr; 1425 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1426 alen = sizeof(struct in6_addr); 1427 break; 1428 default: 1429 perror_reply(425, "Can't build data connection"); 1430 (void) fclose(file); 1431 pdata = -1; 1432 return (NULL); 1433 } 1434 if (data_dest.su_family != his_addr.su_family || 1435 ntohs(*p) < IPPORT_RESERVED || ntohs(*p) == 2049) { /* XXX */ 1436 perror_reply(425, "Can't build data connection"); 1437 (void) fclose(file); 1438 data = -1; 1439 return NULL; 1440 } 1441 if (portcheck && memcmp(fa, ha, alen) != 0) { 1442 perror_reply(435, "Can't build data connection"); 1443 (void) fclose(file); 1444 data = -1; 1445 return NULL; 1446 } 1447 while (connect(data, (struct sockaddr *)&data_dest, 1448 data_dest.su_len) < 0) { 1449 if (errno == EADDRINUSE && retry < swaitmax) { 1450 sleep((unsigned) swaitint); 1451 retry += swaitint; 1452 continue; 1453 } 1454 perror_reply(425, "Can't build data connection"); 1455 (void) fclose(file); 1456 data = -1; 1457 return (NULL); 1458 } 1459 reply(150, "Opening %s mode data connection for '%s'%s.", 1460 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1461 return (file); 1462 } 1463 1464 /* 1465 * Tranfer the contents of "instr" to "outstr" peer using the appropriate 1466 * encapsulation of the data subject to Mode, Structure, and Type. 1467 * 1468 * NB: Form isn't handled. 1469 */ 1470 static int 1471 send_data(FILE *instr, FILE *outstr, off_t blksize, off_t filesize, int isreg) 1472 { 1473 int c, cnt, filefd, netfd; 1474 char *buf, *bp; 1475 size_t len; 1476 1477 transflag++; 1478 switch (type) { 1479 1480 case TYPE_A: 1481 while ((c = getc(instr)) != EOF) { 1482 if (recvurg) 1483 goto got_oob; 1484 byte_count++; 1485 if (c == '\n') { 1486 if (ferror(outstr)) 1487 goto data_err; 1488 (void) putc('\r', outstr); 1489 } 1490 (void) putc(c, outstr); 1491 } 1492 fflush(outstr); 1493 transflag = 0; 1494 if (ferror(instr)) 1495 goto file_err; 1496 if (ferror(outstr)) 1497 goto data_err; 1498 reply(226, "Transfer complete."); 1499 return(0); 1500 1501 case TYPE_I: 1502 case TYPE_L: 1503 /* 1504 * isreg is only set if we are not doing restart and we 1505 * are sending a regular file 1506 */ 1507 netfd = fileno(outstr); 1508 filefd = fileno(instr); 1509 1510 if (isreg && filesize < (off_t)16 * 1024 * 1024) { 1511 buf = mmap(0, filesize, PROT_READ, MAP_SHARED, filefd, 1512 (off_t)0); 1513 if (buf == MAP_FAILED) { 1514 syslog(LOG_WARNING, "mmap(%lu): %m", 1515 (unsigned long)filesize); 1516 goto oldway; 1517 } 1518 bp = buf; 1519 len = filesize; 1520 do { 1521 cnt = write(netfd, bp, len); 1522 if (recvurg) { 1523 munmap(buf, (size_t)filesize); 1524 goto got_oob; 1525 } 1526 len -= cnt; 1527 bp += cnt; 1528 if (cnt > 0) byte_count += cnt; 1529 } while(cnt > 0 && len > 0); 1530 1531 transflag = 0; 1532 munmap(buf, (size_t)filesize); 1533 if (cnt < 0) 1534 goto data_err; 1535 reply(226, "Transfer complete."); 1536 return(0); 1537 } 1538 1539 oldway: 1540 if ((buf = malloc((u_int)blksize)) == NULL) { 1541 transflag = 0; 1542 perror_reply(451, "Local resource failure: malloc"); 1543 return(-1); 1544 } 1545 1546 while ((cnt = read(filefd, buf, (u_int)blksize)) > 0 && 1547 write(netfd, buf, cnt) == cnt) 1548 byte_count += cnt; 1549 transflag = 0; 1550 (void)free(buf); 1551 if (cnt != 0) { 1552 if (cnt < 0) 1553 goto file_err; 1554 goto data_err; 1555 } 1556 reply(226, "Transfer complete."); 1557 return(0); 1558 default: 1559 transflag = 0; 1560 reply(550, "Unimplemented TYPE %d in send_data", type); 1561 return(-1); 1562 } 1563 1564 data_err: 1565 transflag = 0; 1566 perror_reply(426, "Data connection"); 1567 return(-1); 1568 1569 file_err: 1570 transflag = 0; 1571 perror_reply(551, "Error on input file"); 1572 return(-1); 1573 1574 got_oob: 1575 myoob(); 1576 recvurg = 0; 1577 transflag = 0; 1578 return(-1); 1579 } 1580 1581 /* 1582 * Transfer data from peer to "outstr" using the appropriate encapulation of 1583 * the data subject to Mode, Structure, and Type. 1584 * 1585 * N.B.: Form isn't handled. 1586 */ 1587 static int 1588 receive_data(FILE *instr, FILE *outstr) 1589 { 1590 int c; 1591 int cnt; 1592 char buf[BUFSIZ]; 1593 struct sigaction sa, sa_saved; 1594 volatile int bare_lfs = 0; 1595 1596 transflag++; 1597 switch (type) { 1598 1599 case TYPE_I: 1600 case TYPE_L: 1601 memset(&sa, 0, sizeof(sa)); 1602 sigfillset(&sa.sa_mask); 1603 sa.sa_flags = SA_RESTART; 1604 sa.sa_handler = lostconn; 1605 (void) sigaction(SIGALRM, &sa, &sa_saved); 1606 do { 1607 (void) alarm ((unsigned) timeout); 1608 cnt = read(fileno(instr), buf, sizeof(buf)); 1609 (void) alarm (0); 1610 if (recvurg) 1611 goto got_oob; 1612 1613 if (cnt > 0) { 1614 if (write(fileno(outstr), buf, cnt) != cnt) 1615 goto file_err; 1616 byte_count += cnt; 1617 } 1618 } while (cnt > 0); 1619 (void) sigaction(SIGALRM, &sa_saved, NULL); 1620 if (cnt < 0) 1621 goto data_err; 1622 transflag = 0; 1623 return (0); 1624 1625 case TYPE_E: 1626 reply(553, "TYPE E not implemented."); 1627 transflag = 0; 1628 return (-1); 1629 1630 case TYPE_A: 1631 while ((c = getc(instr)) != EOF) { 1632 if (recvurg) 1633 goto got_oob; 1634 byte_count++; 1635 if (c == '\n') 1636 bare_lfs++; 1637 while (c == '\r') { 1638 if (ferror(outstr)) 1639 goto data_err; 1640 if ((c = getc(instr)) != '\n') { 1641 (void) putc ('\r', outstr); 1642 if (c == '\0' || c == EOF) 1643 goto contin2; 1644 } 1645 } 1646 (void) putc(c, outstr); 1647 contin2: ; 1648 } 1649 fflush(outstr); 1650 if (ferror(instr)) 1651 goto data_err; 1652 if (ferror(outstr)) 1653 goto file_err; 1654 transflag = 0; 1655 if (bare_lfs) { 1656 lreply(226, 1657 "WARNING! %d bare linefeeds received in ASCII mode", 1658 bare_lfs); 1659 printf(" File may not have transferred correctly.\r\n"); 1660 } 1661 return (0); 1662 default: 1663 reply(550, "Unimplemented TYPE %d in receive_data", type); 1664 transflag = 0; 1665 return (-1); 1666 } 1667 1668 data_err: 1669 transflag = 0; 1670 perror_reply(426, "Data Connection"); 1671 return (-1); 1672 1673 file_err: 1674 transflag = 0; 1675 perror_reply(452, "Error writing file"); 1676 return (-1); 1677 1678 got_oob: 1679 myoob(); 1680 recvurg = 0; 1681 transflag = 0; 1682 return (-1); 1683 } 1684 1685 void 1686 statfilecmd(char *filename) 1687 { 1688 FILE *fin; 1689 int c; 1690 int atstart; 1691 char line[LINE_MAX]; 1692 1693 (void)snprintf(line, sizeof(line), "/bin/ls -lgA %s", filename); 1694 fin = ftpd_popen(line, "r"); 1695 lreply(211, "status of %s:", filename); 1696 atstart = 1; 1697 while ((c = getc(fin)) != EOF) { 1698 if (c == '\n') { 1699 if (ferror(stdout)){ 1700 perror_reply(421, "control connection"); 1701 (void) ftpd_pclose(fin); 1702 dologout(1); 1703 /* NOTREACHED */ 1704 } 1705 if (ferror(fin)) { 1706 perror_reply(551, filename); 1707 (void) ftpd_pclose(fin); 1708 return; 1709 } 1710 (void) putc('\r', stdout); 1711 } 1712 if (atstart && isdigit(c)) 1713 (void) putc(' ', stdout); 1714 (void) putc(c, stdout); 1715 atstart = (c == '\n'); 1716 } 1717 (void) ftpd_pclose(fin); 1718 reply(211, "End of Status"); 1719 } 1720 1721 void 1722 statcmd(void) 1723 { 1724 union sockunion *su; 1725 u_char *a, *p; 1726 char hbuf[MAXHOSTNAMELEN]; 1727 int ispassive; 1728 1729 lreply(211, "%s FTP server status:", hostname); 1730 printf(" %s\r\n", version); 1731 getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len, 1732 hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST); 1733 printf(" Connected to %s", remotehost); 1734 if (strcmp(remotehost, hbuf) != 0) 1735 printf(" (%s)", hbuf); 1736 printf("\r\n"); 1737 if (logged_in) { 1738 if (guest) 1739 printf(" Logged in anonymously\r\n"); 1740 else 1741 printf(" Logged in as %s\r\n", pw->pw_name); 1742 } else if (askpasswd) 1743 printf(" Waiting for password\r\n"); 1744 else 1745 printf(" Waiting for user name\r\n"); 1746 printf(" TYPE: %s", typenames[type]); 1747 if (type == TYPE_A || type == TYPE_E) 1748 printf(", FORM: %s", formnames[form]); 1749 if (type == TYPE_L) 1750 #if NBBY == 8 1751 printf(" %d", NBBY); 1752 #else 1753 printf(" %d", bytesize); /* need definition! */ 1754 #endif 1755 printf("; STRUcture: %s; transfer MODE: %s\r\n", 1756 strunames[stru], modenames[mode]); 1757 ispassive = 0; 1758 if (data != -1) 1759 printf(" Data connection open\r\n"); 1760 else if (pdata != -1) { 1761 printf(" in Passive mode\r\n"); 1762 su = (union sockunion *)&pasv_addr; 1763 ispassive++; 1764 goto printaddr; 1765 } else if (usedefault == 0) { 1766 su = (union sockunion *)&data_dest; 1767 printaddr: 1768 /* PASV/PORT */ 1769 if (su->su_family == AF_INET) { 1770 if (ispassive) 1771 printf("211- PASV "); 1772 else 1773 printf("211- PORT "); 1774 a = (u_char *) &su->su_sin.sin_addr; 1775 p = (u_char *) &su->su_sin.sin_port; 1776 printf("(%u,%u,%u,%u,%u,%u)\r\n", 1777 a[0], a[1], a[2], a[3], 1778 p[0], p[1]); 1779 } 1780 1781 /* LPSV/LPRT */ 1782 { 1783 int alen, af, i; 1784 1785 alen = 0; 1786 switch (su->su_family) { 1787 case AF_INET: 1788 a = (u_char *) &su->su_sin.sin_addr; 1789 p = (u_char *) &su->su_sin.sin_port; 1790 alen = sizeof(su->su_sin.sin_addr); 1791 af = 4; 1792 break; 1793 case AF_INET6: 1794 a = (u_char *) &su->su_sin6.sin6_addr; 1795 p = (u_char *) &su->su_sin6.sin6_port; 1796 alen = sizeof(su->su_sin6.sin6_addr); 1797 af = 6; 1798 break; 1799 default: 1800 af = 0; 1801 break; 1802 } 1803 if (af) { 1804 if (ispassive) 1805 printf("211- LPSV "); 1806 else 1807 printf("211- LPRT "); 1808 printf("(%u,%u", af, alen); 1809 for (i = 0; i < alen; i++) 1810 printf(",%u", a[i]); 1811 printf(",%u,%u,%u)\r\n", 2, p[0], p[1]); 1812 } 1813 } 1814 1815 /* EPRT/EPSV */ 1816 { 1817 u_char af; 1818 1819 switch (su->su_family) { 1820 case AF_INET: 1821 af = 1; 1822 break; 1823 case AF_INET6: 1824 af = 2; 1825 break; 1826 default: 1827 af = 0; 1828 break; 1829 } 1830 if (af) { 1831 char hbuf[MAXHOSTNAMELEN], pbuf[10]; 1832 union sockunion tmp = *su; 1833 1834 if (tmp.su_family == AF_INET6) 1835 tmp.su_sin6.sin6_scope_id = 0; 1836 if (getnameinfo((struct sockaddr *)&tmp, tmp.su_len, 1837 hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), 1838 NI_NUMERICHOST | NI_NUMERICSERV) == 0) { 1839 if (ispassive) 1840 printf("211- EPSV "); 1841 else 1842 printf("211- EPRT "); 1843 printf("(|%u|%s|%s|)\r\n", 1844 af, hbuf, pbuf); 1845 } 1846 } 1847 } 1848 } else 1849 printf(" No data connection\r\n"); 1850 reply(211, "End of status"); 1851 } 1852 1853 void 1854 fatal(char *s) 1855 { 1856 1857 reply(451, "Error in server: %s", s); 1858 reply(221, "Closing connection due to server error."); 1859 dologout(0); 1860 /* NOTREACHED */ 1861 } 1862 1863 void 1864 reply(int n, const char *fmt, ...) 1865 { 1866 char *buf, *p, *next; 1867 int rval; 1868 va_list ap; 1869 1870 va_start(ap, fmt); 1871 rval = vasprintf(&buf, fmt, ap); 1872 va_end(ap); 1873 if (rval == -1 || buf == NULL) { 1874 printf("412 Local resource failure: malloc\r\n"); 1875 fflush(stdout); 1876 dologout(1); 1877 } 1878 next = buf; 1879 while ((p = strsep(&next, "\n\r"))) { 1880 printf("%d%s %s\r\n", n, (next != '\0') ? "-" : "", p); 1881 if (debug) 1882 syslog(LOG_DEBUG, "<--- %d%s %s", n, 1883 (next != '\0') ? "-" : "", p); 1884 } 1885 (void)fflush(stdout); 1886 free(buf); 1887 } 1888 1889 void 1890 lreply(int n, const char *fmt, ...) 1891 { 1892 va_list ap; 1893 1894 va_start(ap, fmt); 1895 (void)printf("%d- ", n); 1896 (void)vprintf(fmt, ap); 1897 va_end(ap); 1898 (void)printf("\r\n"); 1899 (void)fflush(stdout); 1900 if (debug) { 1901 va_start(ap, fmt); 1902 syslog(LOG_DEBUG, "<--- %d- ", n); 1903 vsyslog(LOG_DEBUG, fmt, ap); 1904 va_end(ap); 1905 } 1906 } 1907 1908 static void 1909 ack(char *s) 1910 { 1911 1912 reply(250, "%s command successful.", s); 1913 } 1914 1915 void 1916 nack(char *s) 1917 { 1918 1919 reply(502, "%s command not implemented.", s); 1920 } 1921 1922 /* ARGSUSED */ 1923 void 1924 yyerror(char *s) 1925 { 1926 char *cp; 1927 1928 if ((cp = strchr(cbuf,'\n'))) 1929 *cp = '\0'; 1930 reply(500, "'%s': command not understood.", cbuf); 1931 } 1932 1933 void 1934 delete(char *name) 1935 { 1936 struct stat st; 1937 1938 LOGCMD("delete", name); 1939 if (stat(name, &st) < 0) { 1940 perror_reply(550, name); 1941 return; 1942 } 1943 if ((st.st_mode&S_IFMT) == S_IFDIR) { 1944 if (rmdir(name) < 0) { 1945 perror_reply(550, name); 1946 return; 1947 } 1948 goto done; 1949 } 1950 if (unlink(name) < 0) { 1951 perror_reply(550, name); 1952 return; 1953 } 1954 done: 1955 ack("DELE"); 1956 } 1957 1958 void 1959 cwd(char *path) 1960 { 1961 FILE *message; 1962 1963 if (chdir(path) < 0) 1964 perror_reply(550, path); 1965 else { 1966 if ((message = fopen(_PATH_CWDMESG, "r")) != NULL) { 1967 char *cp, line[LINE_MAX]; 1968 1969 while (fgets(line, sizeof(line), message) != NULL) { 1970 if ((cp = strchr(line, '\n')) != NULL) 1971 *cp = '\0'; 1972 lreply(250, "%s", line); 1973 } 1974 (void) fflush(stdout); 1975 (void) fclose(message); 1976 } 1977 ack("CWD"); 1978 } 1979 } 1980 1981 void 1982 replydirname(const char *name, const char *message) 1983 { 1984 char *p, *ep; 1985 char npath[MAXPATHLEN * 2]; 1986 1987 p = npath; 1988 ep = &npath[sizeof(npath) - 1]; 1989 while (*name) { 1990 if (*name == '"') { 1991 if (ep - p < 2) 1992 break; 1993 *p++ = *name++; 1994 *p++ = '"'; 1995 } else { 1996 if (ep - p < 1) 1997 break; 1998 *p++ = *name++; 1999 } 2000 } 2001 *p = '\0'; 2002 reply(257, "\"%s\" %s", npath, message); 2003 } 2004 2005 void 2006 makedir(char *name) 2007 { 2008 2009 LOGCMD("mkdir", name); 2010 if (mkdir(name, 0777) < 0) 2011 perror_reply(550, name); 2012 else 2013 replydirname(name, "directory created."); 2014 } 2015 2016 void 2017 removedir(char *name) 2018 { 2019 2020 LOGCMD("rmdir", name); 2021 if (rmdir(name) < 0) 2022 perror_reply(550, name); 2023 else 2024 ack("RMD"); 2025 } 2026 2027 void 2028 pwd(void) 2029 { 2030 char path[MAXPATHLEN]; 2031 2032 if (getcwd(path, sizeof(path)) == NULL) 2033 perror_reply(550, "Can't get current directory"); 2034 else 2035 replydirname(path, "is current directory."); 2036 } 2037 2038 char * 2039 renamefrom(char *name) 2040 { 2041 struct stat st; 2042 2043 if (stat(name, &st) < 0) { 2044 perror_reply(550, name); 2045 return ((char *)0); 2046 } 2047 reply(350, "File exists, ready for destination name"); 2048 return (name); 2049 } 2050 2051 void 2052 renamecmd(char *from, char *to) 2053 { 2054 2055 LOGCMD2("rename", from, to); 2056 if (rename(from, to) < 0) 2057 perror_reply(550, "rename"); 2058 else 2059 ack("RNTO"); 2060 } 2061 2062 static void 2063 dolog(struct sockaddr *sa) 2064 { 2065 char hbuf[sizeof(remotehost)]; 2066 2067 getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), NULL, 0, 0); 2068 (void) strlcpy(remotehost, hbuf, sizeof(remotehost)); 2069 2070 #ifdef HASSETPROCTITLE 2071 snprintf(proctitle, sizeof(proctitle), "%s: connected", remotehost); 2072 setproctitle("%s", proctitle); 2073 #endif /* HASSETPROCTITLE */ 2074 2075 if (logging) 2076 syslog(LOG_INFO, "connection from %s", remotehost); 2077 } 2078 2079 /* 2080 * Record logout in wtmp file and exit with supplied status. 2081 * NOTE: because this is called from signal handlers it cannot 2082 * use stdio (or call other functions that use stdio). 2083 */ 2084 void 2085 dologout(int status) 2086 { 2087 2088 transflag = 0; 2089 2090 if (logged_in) { 2091 sigprocmask(SIG_BLOCK, &allsigs, NULL); 2092 ftpdlogwtmp(ttyline, "", ""); 2093 if (doutmp) 2094 ftpd_logout(utmp.ut_line); 2095 } 2096 /* beware of flushing buffers after a SIGPIPE */ 2097 _exit(status); 2098 } 2099 2100 static void 2101 sigurg(int signo) 2102 { 2103 2104 recvurg = 1; 2105 } 2106 2107 static void 2108 myoob(void) 2109 { 2110 char *cp; 2111 2112 /* only process if transfer occurring */ 2113 if (!transflag) 2114 return; 2115 cp = tmpline; 2116 if (getline(cp, 7, stdin) == NULL) { 2117 reply(221, "You could at least say goodbye."); 2118 dologout(0); 2119 } 2120 upper(cp); 2121 if (strcmp(cp, "ABOR\r\n") == 0) { 2122 tmpline[0] = '\0'; 2123 reply(426, "Transfer aborted. Data connection closed."); 2124 reply(226, "Abort successful"); 2125 } 2126 if (strcmp(cp, "STAT\r\n") == 0) { 2127 tmpline[0] = '\0'; 2128 if (file_size != (off_t) -1) 2129 reply(213, "Status: %qd of %qd bytes transferred", 2130 byte_count, file_size); 2131 else 2132 reply(213, "Status: %qd bytes transferred", byte_count); 2133 } 2134 } 2135 2136 /* 2137 * Note: a response of 425 is not mentioned as a possible response to 2138 * the PASV command in RFC959. However, it has been blessed as 2139 * a legitimate response by Jon Postel in a telephone conversation 2140 * with Rick Adams on 25 Jan 89. 2141 */ 2142 void 2143 passive(void) 2144 { 2145 socklen_t len; 2146 int on; 2147 u_char *p, *a; 2148 2149 if (pw == NULL) { 2150 reply(530, "Please login with USER and PASS"); 2151 return; 2152 } 2153 if (pdata >= 0) 2154 close(pdata); 2155 /* 2156 * XXX 2157 * At this point, it would be nice to have an algorithm that 2158 * inserted a growing delay in an attack scenario. Such a thing 2159 * would look like continual passive sockets being opened, but 2160 * nothing serious being done with them. They're not used to 2161 * move data; the entire attempt is just to use tcp FIN_WAIT 2162 * resources. 2163 */ 2164 pdata = socket(AF_INET, SOCK_STREAM, 0); 2165 if (pdata < 0) { 2166 perror_reply(425, "Can't open passive connection"); 2167 return; 2168 } 2169 2170 on = IP_PORTRANGE_HIGH; 2171 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2172 (char *)&on, sizeof(on)) < 0) 2173 goto pasv_error; 2174 2175 pasv_addr = ctrl_addr; 2176 pasv_addr.su_sin.sin_port = 0; 2177 if (bind(pdata, (struct sockaddr *)&pasv_addr, 2178 pasv_addr.su_len) < 0) 2179 goto pasv_error; 2180 2181 len = sizeof(pasv_addr); 2182 if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0) 2183 goto pasv_error; 2184 if (listen(pdata, 1) < 0) 2185 goto pasv_error; 2186 a = (u_char *) &pasv_addr.su_sin.sin_addr; 2187 p = (u_char *) &pasv_addr.su_sin.sin_port; 2188 2189 reply(227, "Entering Passive Mode (%u,%u,%u,%u,%u,%u)", a[0], 2190 a[1], a[2], a[3], p[0], p[1]); 2191 return; 2192 2193 pasv_error: 2194 (void) close(pdata); 2195 pdata = -1; 2196 perror_reply(425, "Can't open passive connection"); 2197 return; 2198 } 2199 2200 /* 2201 * convert protocol identifier to/from AF 2202 */ 2203 int 2204 lpsvproto2af(int proto) 2205 { 2206 2207 switch (proto) { 2208 case 4: return AF_INET; 2209 #ifdef INET6 2210 case 6: return AF_INET6; 2211 #endif 2212 default: return -1; 2213 } 2214 } 2215 2216 int 2217 af2lpsvproto(int af) 2218 { 2219 2220 switch (af) { 2221 case AF_INET: return 4; 2222 #ifdef INET6 2223 case AF_INET6: return 6; 2224 #endif 2225 default: return -1; 2226 } 2227 } 2228 2229 int 2230 epsvproto2af(int proto) 2231 { 2232 2233 switch (proto) { 2234 case 1: return AF_INET; 2235 #ifdef INET6 2236 case 2: return AF_INET6; 2237 #endif 2238 default: return -1; 2239 } 2240 } 2241 2242 int 2243 af2epsvproto(int af) 2244 { 2245 2246 switch (af) { 2247 case AF_INET: return 1; 2248 #ifdef INET6 2249 case AF_INET6: return 2; 2250 #endif 2251 default: return -1; 2252 } 2253 } 2254 2255 /* 2256 * 228 Entering Long Passive Mode (af, hal, h1, h2, h3,..., pal, p1, p2...) 2257 * 229 Entering Extended Passive Mode (|||port|) 2258 */ 2259 void 2260 long_passive(char *cmd, int pf) 2261 { 2262 socklen_t len; 2263 int on; 2264 u_char *p, *a; 2265 2266 if (!logged_in) { 2267 syslog(LOG_NOTICE, "long passive but not logged in"); 2268 reply(503, "Login with USER first."); 2269 return; 2270 } 2271 2272 if (pf != PF_UNSPEC && ctrl_addr.su_family != pf) { 2273 /* 2274 * XXX 2275 * only EPRT/EPSV ready clients will understand this 2276 */ 2277 if (strcmp(cmd, "EPSV") != 0) 2278 reply(501, "Network protocol mismatch"); /*XXX*/ 2279 else 2280 epsv_protounsupp("Network protocol mismatch"); 2281 2282 return; 2283 } 2284 2285 if (pdata >= 0) 2286 close(pdata); 2287 /* 2288 * XXX 2289 * At this point, it would be nice to have an algorithm that 2290 * inserted a growing delay in an attack scenario. Such a thing 2291 * would look like continual passive sockets being opened, but 2292 * nothing serious being done with them. They not used to move 2293 * data; the entire attempt is just to use tcp FIN_WAIT 2294 * resources. 2295 */ 2296 pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 2297 if (pdata < 0) { 2298 perror_reply(425, "Can't open passive connection"); 2299 return; 2300 } 2301 2302 switch (ctrl_addr.su_family) { 2303 case AF_INET: 2304 on = IP_PORTRANGE_HIGH; 2305 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2306 (char *)&on, sizeof(on)) < 0) 2307 goto pasv_error; 2308 break; 2309 case AF_INET6: 2310 on = IPV6_PORTRANGE_HIGH; 2311 if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE, 2312 (char *)&on, sizeof(on)) < 0) 2313 goto pasv_error; 2314 break; 2315 } 2316 2317 pasv_addr = ctrl_addr; 2318 pasv_addr.su_port = 0; 2319 if (bind(pdata, (struct sockaddr *) &pasv_addr, pasv_addr.su_len) < 0) 2320 goto pasv_error; 2321 len = pasv_addr.su_len; 2322 if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0) 2323 goto pasv_error; 2324 if (listen(pdata, 1) < 0) 2325 goto pasv_error; 2326 p = (u_char *) &pasv_addr.su_port; 2327 2328 if (strcmp(cmd, "LPSV") == 0) { 2329 switch (pasv_addr.su_family) { 2330 case AF_INET: 2331 a = (u_char *) &pasv_addr.su_sin.sin_addr; 2332 reply(228, 2333 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2334 4, 4, a[0], a[1], a[2], a[3], 2, p[0], p[1]); 2335 return; 2336 case AF_INET6: 2337 a = (u_char *) &pasv_addr.su_sin6.sin6_addr; 2338 reply(228, 2339 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u," 2340 "%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2341 6, 16, a[0], a[1], a[2], a[3], a[4], 2342 a[5], a[6], a[7], a[8], a[9], a[10], 2343 a[11], a[12], a[13], a[14], a[15], 2344 2, p[0], p[1]); 2345 return; 2346 } 2347 } else if (strcmp(cmd, "EPSV") == 0) { 2348 switch (pasv_addr.su_family) { 2349 case AF_INET: 2350 case AF_INET6: 2351 reply(229, "Entering Extended Passive Mode (|||%u|)", 2352 ntohs(pasv_addr.su_port)); 2353 return; 2354 } 2355 } else { 2356 /* more proper error code? */ 2357 } 2358 2359 pasv_error: 2360 (void) close(pdata); 2361 pdata = -1; 2362 perror_reply(425, "Can't open passive connection"); 2363 return; 2364 } 2365 2366 /* 2367 * EPRT |proto|addr|port| 2368 */ 2369 int 2370 extended_port(const char *arg) 2371 { 2372 char *tmp = NULL; 2373 char *result[3]; 2374 char *p, *q; 2375 char delim; 2376 struct addrinfo hints; 2377 struct addrinfo *res = NULL; 2378 int i; 2379 unsigned long proto; 2380 2381 if (epsvall) { 2382 reply(501, "EPRT disallowed after EPSV ALL"); 2383 return -1; 2384 } 2385 2386 usedefault = 0; 2387 if (pdata >= 0) { 2388 (void) close(pdata); 2389 pdata = -1; 2390 } 2391 2392 tmp = strdup(arg); 2393 if (!tmp) { 2394 fatal("not enough core."); 2395 /*NOTREACHED*/ 2396 } 2397 p = tmp; 2398 delim = p[0]; 2399 p++; 2400 memset(result, 0, sizeof(result)); 2401 for (i = 0; i < 3; i++) { 2402 q = strchr(p, delim); 2403 if (!q || *q != delim) 2404 goto parsefail; 2405 *q++ = '\0'; 2406 result[i] = p; 2407 p = q; 2408 } 2409 2410 /* some more sanity check */ 2411 p = NULL; 2412 (void)strtoul(result[2], &p, 10); 2413 if (!*result[2] || *p) 2414 goto protounsupp; 2415 p = NULL; 2416 proto = strtoul(result[0], &p, 10); 2417 if (!*result[0] || *p) 2418 goto protounsupp; 2419 2420 memset(&hints, 0, sizeof(hints)); 2421 hints.ai_family = epsvproto2af((int)proto); 2422 if (hints.ai_family < 0) 2423 goto protounsupp; 2424 hints.ai_socktype = SOCK_STREAM; 2425 hints.ai_flags = AI_NUMERICHOST; /*no DNS*/ 2426 if (getaddrinfo(result[1], result[2], &hints, &res)) 2427 goto parsefail; 2428 if (res->ai_next) 2429 goto parsefail; 2430 if (sizeof(data_dest) < res->ai_addrlen) 2431 goto parsefail; 2432 memcpy(&data_dest, res->ai_addr, res->ai_addrlen); 2433 if (his_addr.su_family == AF_INET6 && 2434 data_dest.su_family == AF_INET6) { 2435 /* XXX more sanity checks! */ 2436 data_dest.su_sin6.sin6_scope_id = 2437 his_addr.su_sin6.sin6_scope_id; 2438 } 2439 if (pdata >= 0) { 2440 (void) close(pdata); 2441 pdata = -1; 2442 } 2443 reply(200, "EPRT command successful."); 2444 2445 if (tmp) 2446 free(tmp); 2447 if (res) 2448 freeaddrinfo(res); 2449 return 0; 2450 2451 parsefail: 2452 reply(500, "Invalid argument, rejected."); 2453 usedefault = 1; 2454 if (tmp) 2455 free(tmp); 2456 if (res) 2457 freeaddrinfo(res); 2458 return -1; 2459 2460 protounsupp: 2461 epsv_protounsupp("Protocol not supported"); 2462 usedefault = 1; 2463 if (tmp) 2464 free(tmp); 2465 if (res) 2466 freeaddrinfo(res); 2467 return -1; 2468 } 2469 2470 /* 2471 * 522 Protocol not supported (proto,...) 2472 * as we assume address family for control and data connections are the same, 2473 * we do not return the list of address families we support - instead, we 2474 * return the address family of the control connection. 2475 */ 2476 void 2477 epsv_protounsupp(const char *message) 2478 { 2479 int proto; 2480 2481 proto = af2epsvproto(ctrl_addr.su_family); 2482 if (proto < 0) 2483 reply(501, "%s", message); /*XXX*/ 2484 else 2485 reply(522, "%s, use (%d)", message, proto); 2486 } 2487 2488 /* 2489 * Generate unique name for file with basename "local". 2490 * The file named "local" is already known to exist. 2491 * Generates failure reply on error. 2492 */ 2493 static int 2494 guniquefd(char *local, char **nam) 2495 { 2496 static char new[MAXPATHLEN]; 2497 struct stat st; 2498 int count, len, fd; 2499 char *cp; 2500 2501 cp = strrchr(local, '/'); 2502 if (cp) 2503 *cp = '\0'; 2504 if (stat(cp ? local : ".", &st) < 0) { 2505 perror_reply(553, cp ? local : "."); 2506 return (-1); 2507 } 2508 if (cp) 2509 *cp = '/'; 2510 len = strlcpy(new, local, sizeof(new)); 2511 if (len+2+1 >= sizeof(new)-1) 2512 return (-1); 2513 cp = new + len; 2514 *cp++ = '.'; 2515 for (count = 1; count < 100; count++) { 2516 (void)snprintf(cp, sizeof(new) - (cp - new), "%d", count); 2517 fd = open(new, O_RDWR|O_CREAT|O_EXCL, 0666); 2518 if (fd == -1) 2519 continue; 2520 if (nam) 2521 *nam = new; 2522 return (fd); 2523 } 2524 reply(452, "Unique file name cannot be created."); 2525 return (-1); 2526 } 2527 2528 /* 2529 * Format and send reply containing system error number. 2530 */ 2531 void 2532 perror_reply(int code, char *string) 2533 { 2534 2535 reply(code, "%s: %s.", string, strerror(errno)); 2536 } 2537 2538 static char *onefile[] = { 2539 "", 2540 0 2541 }; 2542 2543 void 2544 send_file_list(char *whichf) 2545 { 2546 struct stat st; 2547 DIR *dirp = NULL; 2548 struct dirent *dir; 2549 FILE *dout = NULL; 2550 char **dirlist; 2551 char *dirname; 2552 int simple = 0; 2553 volatile int freeglob = 0; 2554 glob_t gl; 2555 2556 if (strpbrk(whichf, "~{[*?") != NULL) { 2557 memset(&gl, 0, sizeof(gl)); 2558 freeglob = 1; 2559 if (glob(whichf, 2560 GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE|GLOB_LIMIT, 2561 0, &gl)) { 2562 reply(550, "not found"); 2563 goto out; 2564 } else if (gl.gl_pathc == 0) { 2565 errno = ENOENT; 2566 perror_reply(550, whichf); 2567 goto out; 2568 } 2569 dirlist = gl.gl_pathv; 2570 } else { 2571 onefile[0] = whichf; 2572 dirlist = onefile; 2573 simple = 1; 2574 } 2575 2576 while ((dirname = *dirlist++)) { 2577 if (stat(dirname, &st) < 0) { 2578 /* 2579 * If user typed "ls -l", etc, and the client 2580 * used NLST, do what the user meant. 2581 */ 2582 if (dirname[0] == '-' && *dirlist == NULL && 2583 transflag == 0) { 2584 retrieve("/bin/ls %s", dirname); 2585 goto out; 2586 } 2587 perror_reply(550, whichf); 2588 if (dout != NULL) { 2589 (void) fclose(dout); 2590 transflag = 0; 2591 data = -1; 2592 pdata = -1; 2593 } 2594 goto out; 2595 } 2596 2597 if (S_ISREG(st.st_mode)) { 2598 if (dout == NULL) { 2599 dout = dataconn("file list", (off_t)-1, "w"); 2600 if (dout == NULL) 2601 goto out; 2602 transflag++; 2603 } 2604 fprintf(dout, "%s%s\n", dirname, 2605 type == TYPE_A ? "\r" : ""); 2606 byte_count += strlen(dirname) + 1; 2607 continue; 2608 } else if (!S_ISDIR(st.st_mode)) 2609 continue; 2610 2611 if ((dirp = opendir(dirname)) == NULL) 2612 continue; 2613 2614 while ((dir = readdir(dirp)) != NULL) { 2615 char nbuf[MAXPATHLEN]; 2616 2617 if (recvurg) { 2618 myoob(); 2619 recvurg = 0; 2620 transflag = 0; 2621 goto out; 2622 } 2623 2624 if (dir->d_name[0] == '.' && dir->d_namlen == 1) 2625 continue; 2626 if (dir->d_name[0] == '.' && dir->d_name[1] == '.' && 2627 dir->d_namlen == 2) 2628 continue; 2629 2630 snprintf(nbuf, sizeof(nbuf), "%s/%s", dirname, 2631 dir->d_name); 2632 2633 /* 2634 * We have to do a stat to insure it's 2635 * not a directory or special file. 2636 */ 2637 if (simple || (stat(nbuf, &st) == 0 && 2638 S_ISREG(st.st_mode))) { 2639 if (dout == NULL) { 2640 dout = dataconn("file list", (off_t)-1, 2641 "w"); 2642 if (dout == NULL) 2643 goto out; 2644 transflag++; 2645 } 2646 if (nbuf[0] == '.' && nbuf[1] == '/') 2647 fprintf(dout, "%s%s\n", &nbuf[2], 2648 type == TYPE_A ? "\r" : ""); 2649 else 2650 fprintf(dout, "%s%s\n", nbuf, 2651 type == TYPE_A ? "\r" : ""); 2652 byte_count += strlen(nbuf) + 1; 2653 } 2654 } 2655 (void) closedir(dirp); 2656 } 2657 2658 if (dout == NULL) 2659 reply(550, "No files found."); 2660 else if (ferror(dout) != 0) 2661 perror_reply(550, "Data connection"); 2662 else 2663 reply(226, "Transfer complete."); 2664 2665 transflag = 0; 2666 if (dout != NULL) 2667 (void) fclose(dout); 2668 else { 2669 if (pdata >= 0) 2670 close(pdata); 2671 } 2672 data = -1; 2673 pdata = -1; 2674 out: 2675 if (freeglob) { 2676 freeglob = 0; 2677 globfree(&gl); 2678 } 2679 } 2680 2681 static void 2682 reapchild(int signo) 2683 { 2684 int save_errno = errno; 2685 int rval; 2686 2687 do { 2688 rval = waitpid(-1, NULL, WNOHANG); 2689 } while (rval > 0 || (rval == -1 && errno == EINTR)); 2690 errno = save_errno; 2691 } 2692 2693 void 2694 logxfer(char *name, off_t size, time_t start) 2695 { 2696 char buf[400 + MAXHOSTNAMELEN*4 + MAXPATHLEN*4]; 2697 char dir[MAXPATHLEN], path[MAXPATHLEN], rpath[MAXPATHLEN]; 2698 char vremotehost[MAXHOSTNAMELEN*4], vpath[MAXPATHLEN*4]; 2699 char *vpw; 2700 time_t now; 2701 int len; 2702 2703 if ((statfd >= 0) && (getcwd(dir, sizeof(dir)) != NULL)) { 2704 time(&now); 2705 2706 vpw = malloc(strlen(guest ? guestpw : pw->pw_name) * 4 + 1); 2707 if (vpw == NULL) 2708 return; 2709 2710 snprintf(path, sizeof(path), "%s/%s", dir, name); 2711 if (realpath(path, rpath) == NULL) 2712 strlcpy(rpath, path, sizeof(rpath)); 2713 strvis(vpath, rpath, VIS_SAFE|VIS_NOSLASH); 2714 2715 strvis(vremotehost, remotehost, VIS_SAFE|VIS_NOSLASH); 2716 strvis(vpw, guest? guestpw : pw->pw_name, VIS_SAFE|VIS_NOSLASH); 2717 2718 if ((len = snprintf(buf, sizeof(buf), 2719 "%.24s %d %s %qd %s %c %s %c %c %s ftp %d %s %s\n", 2720 ctime(&now), now - start + (now == start), 2721 vremotehost, (long long)size, vpath, 2722 ((type == TYPE_A) ? 'a' : 'b'), "*" /* none yet */, 2723 'o', ((guest) ? 'a' : 'r'), 2724 vpw, 0 /* none yet */, 2725 ((guest) ? "*" : pw->pw_name), dhostname)) >= sizeof(buf) 2726 || len < 0) { 2727 if ((len = strlen(buf)) == 0) 2728 return; /* should not happen */ 2729 buf[len - 1] = '\n'; 2730 } 2731 write(statfd, buf, len); 2732 free(vpw); 2733 } 2734 } 2735 2736 #if defined(TCPWRAPPERS) 2737 static int 2738 check_host(struct sockaddr *sa) 2739 { 2740 struct sockaddr_in *sin; 2741 struct hostent *hp; 2742 char *addr; 2743 2744 if (sa->sa_family != AF_INET) 2745 return 1; /*XXX*/ 2746 2747 sin = (struct sockaddr_in *)sa; 2748 hp = gethostbyaddr((char *)&sin->sin_addr, 2749 sizeof(struct in_addr), AF_INET); 2750 addr = inet_ntoa(sin->sin_addr); 2751 if (hp) { 2752 if (!hosts_ctl("ftpd", hp->h_name, addr, STRING_UNKNOWN)) { 2753 syslog(LOG_NOTICE, "tcpwrappers rejected: %s [%s]", 2754 hp->h_name, addr); 2755 return (0); 2756 } 2757 } else { 2758 if (!hosts_ctl("ftpd", STRING_UNKNOWN, addr, STRING_UNKNOWN)) { 2759 syslog(LOG_NOTICE, "tcpwrappers rejected: [%s]", addr); 2760 return (0); 2761 } 2762 } 2763 return (1); 2764 } 2765 #endif /* TCPWRAPPERS */ 2766 2767 /* 2768 * Allocate space and return a copy of the specified dir. 2769 * If 'dir' begins with a tilde (~), expand it. 2770 */ 2771 char * 2772 copy_dir(char *dir, struct passwd *pw) 2773 { 2774 char *cp; 2775 char *newdir; 2776 char *user = NULL; 2777 size_t dirsiz; 2778 2779 /* Nothing to expand */ 2780 if (dir[0] != '~') 2781 return (strdup(dir)); 2782 2783 /* "dir" is of form ~user/some/dir, lookup user. */ 2784 if (dir[1] != '/' && dir[1] != '\0') { 2785 if ((cp = strchr(dir + 1, '/')) == NULL) 2786 cp = dir + strlen(dir); 2787 if ((user = malloc(cp - dir)) == NULL) 2788 return (NULL); 2789 strlcpy(user, dir + 1, cp - dir); 2790 2791 /* Only do lookup if it is a different user. */ 2792 if (strcmp(user, pw->pw_name) != 0) { 2793 if ((pw = getpwnam(user)) == NULL) { 2794 /* No such user, interpret literally */ 2795 free(user); 2796 return(strdup(dir)); 2797 } 2798 } 2799 } 2800 2801 /* 2802 * If there is no directory separator (/) then it is just pw_dir. 2803 * Otherwise, replace ~foo with pw_dir. 2804 */ 2805 if ((cp = strchr(dir + 1, '/')) == NULL) { 2806 newdir = strdup(pw->pw_dir); 2807 } else { 2808 dirsiz = strlen(cp) + strlen(pw->pw_dir) + 1; 2809 if ((newdir = malloc(dirsiz)) == NULL) { 2810 free(user); 2811 return (NULL); 2812 } 2813 strlcpy(newdir, pw->pw_dir, dirsiz); 2814 strlcat(newdir, cp, dirsiz); 2815 } 2816 2817 if (user) 2818 free(user); 2819 return(newdir); 2820 } 2821