1 /* $OpenBSD: ftpd.c,v 1.103 2001/07/08 21:18:07 deraadt Exp $ */ 2 /* $NetBSD: ftpd.c,v 1.15 1995/06/03 22:46:47 mycroft Exp $ */ 3 4 /* 5 * Copyright (C) 1997 and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. All advertising materials mentioning features or use of this software 46 * must display the following acknowledgement: 47 * This product includes software developed by the University of 48 * California, Berkeley and its contributors. 49 * 4. Neither the name of the University nor the names of its contributors 50 * may be used to endorse or promote products derived from this software 51 * without specific prior written permission. 52 * 53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 56 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 63 * SUCH DAMAGE. 64 */ 65 66 #ifndef lint 67 static char copyright[] = 68 "@(#) Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994\n\ 69 The Regents of the University of California. All rights reserved.\n"; 70 #endif /* not lint */ 71 72 #ifndef lint 73 #if 0 74 static char sccsid[] = "@(#)ftpd.c 8.4 (Berkeley) 4/16/94"; 75 #else 76 static char rcsid[] = "$OpenBSD: ftpd.c,v 1.103 2001/07/08 21:18:07 deraadt Exp $"; 77 #endif 78 #endif /* not lint */ 79 80 /* 81 * FTP server. 82 */ 83 #include <sys/param.h> 84 #include <sys/stat.h> 85 #include <sys/ioctl.h> 86 #include <sys/socket.h> 87 #include <sys/wait.h> 88 #include <sys/mman.h> 89 90 #include <netinet/in.h> 91 #include <netinet/in_systm.h> 92 #include <netinet/ip.h> 93 #include <netinet/tcp.h> 94 95 #define FTP_NAMES 96 #include <arpa/ftp.h> 97 #include <arpa/inet.h> 98 #include <arpa/telnet.h> 99 100 #include <ctype.h> 101 #include <dirent.h> 102 #include <err.h> 103 #include <errno.h> 104 #include <fcntl.h> 105 #include <glob.h> 106 #include <limits.h> 107 #include <login_cap.h> 108 #include <netdb.h> 109 #include <pwd.h> 110 #include <setjmp.h> 111 #include <signal.h> 112 #include <stdio.h> 113 #include <stdlib.h> 114 #include <string.h> 115 #include <syslog.h> 116 #include <time.h> 117 #include <vis.h> 118 #include <unistd.h> 119 #include <util.h> 120 #include <utmp.h> 121 #include <bsd_auth.h> 122 123 #if defined(TCPWRAPPERS) 124 #include <tcpd.h> 125 #endif /* TCPWRAPPERS */ 126 127 #include "pathnames.h" 128 #include "extern.h" 129 130 #ifdef __STDC__ 131 #include <stdarg.h> 132 #else 133 #include <varargs.h> 134 #endif 135 136 static char version[] = "Version 6.5/OpenBSD"; 137 138 extern off_t restart_point; 139 extern char cbuf[]; 140 141 union sockunion server_addr; 142 union sockunion ctrl_addr; 143 union sockunion data_source; 144 union sockunion data_dest; 145 union sockunion his_addr; 146 union sockunion pasv_addr; 147 148 sigset_t allsigs; 149 150 int daemon_mode = 0; 151 int data; 152 jmp_buf errcatch, urgcatch; 153 int logged_in; 154 struct passwd *pw; 155 int debug = 0; 156 int timeout = 900; /* timeout after 15 minutes of inactivity */ 157 int maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */ 158 int logging; 159 int high_data_ports = 0; 160 int anon_only = 0; 161 int multihome = 0; 162 int guest; 163 int stats; 164 int statfd = -1; 165 int portcheck = 1; 166 int dochroot; 167 int type; 168 int form; 169 int stru; /* avoid C keyword */ 170 int mode; 171 int doutmp = 0; /* update utmp file */ 172 int usedefault = 1; /* for data transfers */ 173 int pdata = -1; /* for passive mode */ 174 int family = AF_INET; 175 sig_atomic_t transflag; 176 off_t file_size; 177 off_t byte_count; 178 #if !defined(CMASK) || CMASK == 0 179 #undef CMASK 180 #define CMASK 022 181 #endif 182 int defumask = CMASK; /* default umask value */ 183 int umaskchange = 1; /* allow user to change umask value. */ 184 char tmpline[7]; 185 char hostname[MAXHOSTNAMELEN]; 186 char remotehost[MAXHOSTNAMELEN]; 187 char dhostname[MAXHOSTNAMELEN]; 188 char *guestpw; 189 static char ttyline[20]; 190 char *tty = ttyline; /* for klogin */ 191 static struct utmp utmp; /* for utmp */ 192 static login_cap_t *lc; 193 static auth_session_t *as; 194 195 #if defined(TCPWRAPPERS) 196 int allow_severity = LOG_INFO; 197 int deny_severity = LOG_NOTICE; 198 #endif /* TCPWRAPPERS */ 199 200 char *ident = NULL; 201 202 203 int epsvall = 0; 204 205 /* 206 * Timeout intervals for retrying connections 207 * to hosts that don't accept PORT cmds. This 208 * is a kludge, but given the problems with TCP... 209 */ 210 #define SWAITMAX 90 /* wait at most 90 seconds */ 211 #define SWAITINT 5 /* interval between retries */ 212 213 int swaitmax = SWAITMAX; 214 int swaitint = SWAITINT; 215 216 #ifdef HASSETPROCTITLE 217 char proctitle[BUFSIZ]; /* initial part of title */ 218 #endif /* HASSETPROCTITLE */ 219 220 #define LOGCMD(cmd, file) \ 221 if (logging > 1) \ 222 syslog(LOG_INFO,"%s %s%s", cmd, \ 223 *(file) == '/' ? "" : curdir(), file); 224 #define LOGCMD2(cmd, file1, file2) \ 225 if (logging > 1) \ 226 syslog(LOG_INFO,"%s %s%s %s%s", cmd, \ 227 *(file1) == '/' ? "" : curdir(), file1, \ 228 *(file2) == '/' ? "" : curdir(), file2); 229 #define LOGBYTES(cmd, file, cnt) \ 230 if (logging > 1) { \ 231 if (cnt == (off_t)-1) \ 232 syslog(LOG_INFO,"%s %s%s", cmd, \ 233 *(file) == '/' ? "" : curdir(), file); \ 234 else \ 235 syslog(LOG_INFO, "%s %s%s = %qd bytes", \ 236 cmd, (*(file) == '/') ? "" : curdir(), file, cnt); \ 237 } 238 239 static void ack __P((char *)); 240 static void myoob __P((int)); 241 static int checkuser __P((char *, char *)); 242 static FILE *dataconn __P((char *, off_t, char *)); 243 static void dolog __P((struct sockaddr *)); 244 static char *copy_dir __P((char *, struct passwd *)); 245 static char *curdir __P((void)); 246 static void end_login __P((void)); 247 static FILE *getdatasock __P((char *)); 248 static int guniquefd __P((char *, char **)); 249 static void lostconn __P((int)); 250 static void sigquit __P((int)); 251 static int receive_data __P((FILE *, FILE *)); 252 static void replydirname __P((const char *, const char *)); 253 static void send_data __P((FILE *, FILE *, off_t, off_t, int)); 254 static struct passwd * 255 sgetpwnam __P((char *)); 256 static void reapchild __P((int)); 257 static int check_host __P((struct sockaddr *)); 258 static void usage __P((void)); 259 260 void logxfer __P((char *, off_t, time_t)); 261 262 static char * 263 curdir() 264 { 265 static char path[MAXPATHLEN+1]; /* path + '/' */ 266 267 if (getcwd(path, sizeof(path)-1) == NULL) 268 return (""); 269 if (path[1] != '\0') /* special case for root dir. */ 270 strcat(path, "/"); 271 /* For guest account, skip / since it's chrooted */ 272 return (guest ? path+1 : path); 273 } 274 275 char *argstr = "AdDhlMSt:T:u:UvP46"; 276 277 static void 278 usage() 279 { 280 syslog(LOG_ERR, 281 "usage: ftpd [-AdDhlMSUv] [-t timeout] [-T maxtimeout] [-u mask]"); 282 exit(2); 283 } 284 285 int 286 main(argc, argv, envp) 287 int argc; 288 char *argv[]; 289 char **envp; 290 { 291 int addrlen, ch, on = 1, tos; 292 char *cp, line[LINE_MAX]; 293 FILE *fp; 294 struct hostent *hp; 295 296 tzset(); /* in case no timezone database in ~ftp */ 297 sigfillset(&allsigs); /* used to block signals while root */ 298 299 while ((ch = getopt(argc, argv, argstr)) != -1) { 300 switch (ch) { 301 case 'A': 302 anon_only = 1; 303 break; 304 305 case 'd': 306 debug = 1; 307 break; 308 309 case 'D': 310 daemon_mode = 1; 311 break; 312 313 case 'P': 314 portcheck = 0; 315 break; 316 317 case 'h': 318 high_data_ports = 1; 319 break; 320 321 case 'l': 322 logging++; /* > 1 == extra logging */ 323 break; 324 325 case 'M': 326 multihome = 1; 327 break; 328 329 case 'S': 330 stats = 1; 331 break; 332 333 case 't': 334 timeout = atoi(optarg); 335 if (maxtimeout < timeout) 336 maxtimeout = timeout; 337 break; 338 339 case 'T': 340 maxtimeout = atoi(optarg); 341 if (timeout > maxtimeout) 342 timeout = maxtimeout; 343 break; 344 345 case 'u': 346 { 347 long val = 0; 348 char *p; 349 umaskchange = 0; 350 351 val = strtol(optarg, &p, 8); 352 if (*p != '\0' || val < 0 || (val & ~ACCESSPERMS)) { 353 syslog(LOG_ERR, 354 "ftpd: %s is a bad value for -u, aborting..", 355 optarg); 356 exit(2); 357 } else 358 defumask = val; 359 break; 360 } 361 362 case 'U': 363 doutmp = 1; 364 break; 365 366 case 'v': 367 debug = 1; 368 break; 369 370 case '4': 371 family = AF_INET; 372 break; 373 374 case '6': 375 family = AF_INET6; 376 break; 377 378 default: 379 usage(); 380 break; 381 } 382 } 383 384 (void) freopen(_PATH_DEVNULL, "w", stderr); 385 386 /* 387 * LOG_NDELAY sets up the logging connection immediately, 388 * necessary for anonymous ftp's that chroot and can't do it later. 389 */ 390 openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP); 391 392 if (daemon_mode) { 393 int ctl_sock, fd; 394 struct servent *sv; 395 396 /* 397 * Detach from parent. 398 */ 399 if (daemon(1, 1) < 0) { 400 syslog(LOG_ERR, "failed to become a daemon"); 401 exit(1); 402 } 403 (void) signal(SIGCHLD, reapchild); 404 /* 405 * Get port number for ftp/tcp. 406 */ 407 sv = getservbyname("ftp", "tcp"); 408 if (sv == NULL) { 409 syslog(LOG_ERR, "getservbyname for ftp failed"); 410 exit(1); 411 } 412 /* 413 * Open a socket, bind it to the FTP port, and start 414 * listening. 415 */ 416 ctl_sock = socket(family, SOCK_STREAM, 0); 417 if (ctl_sock < 0) { 418 syslog(LOG_ERR, "control socket: %m"); 419 exit(1); 420 } 421 if (setsockopt(ctl_sock, SOL_SOCKET, SO_REUSEADDR, 422 (char *)&on, sizeof(on)) < 0) 423 syslog(LOG_ERR, "control setsockopt: %m"); 424 memset(&server_addr, 0, sizeof(server_addr)); 425 server_addr.su_sin.sin_family = family; 426 switch (family) { 427 case AF_INET: 428 server_addr.su_len = sizeof(struct sockaddr_in); 429 server_addr.su_sin.sin_port = sv->s_port; 430 break; 431 case AF_INET6: 432 server_addr.su_len = sizeof(struct sockaddr_in6); 433 server_addr.su_sin6.sin6_port = sv->s_port; 434 break; 435 } 436 if (bind(ctl_sock, (struct sockaddr *)&server_addr, 437 server_addr.su_len)) { 438 syslog(LOG_ERR, "control bind: %m"); 439 exit(1); 440 } 441 if (listen(ctl_sock, 32) < 0) { 442 syslog(LOG_ERR, "control listen: %m"); 443 exit(1); 444 } 445 /* Stash pid in pidfile */ 446 if ((fp = fopen(_PATH_FTPDPID, "w")) == NULL) 447 syslog(LOG_ERR, "can't open %s: %m", _PATH_FTPDPID); 448 else { 449 fprintf(fp, "%d\n", getpid()); 450 fchmod(fileno(fp), S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH); 451 fclose(fp); 452 } 453 /* 454 * Loop forever accepting connection requests and forking off 455 * children to handle them. 456 */ 457 while (1) { 458 addrlen = sizeof(his_addr); 459 fd = accept(ctl_sock, (struct sockaddr *)&his_addr, 460 &addrlen); 461 if (fork() == 0) { 462 /* child */ 463 (void) dup2(fd, 0); 464 (void) dup2(fd, 1); 465 close(ctl_sock); 466 break; 467 } 468 close(fd); 469 } 470 471 #if defined(TCPWRAPPERS) 472 /* ..in the child. */ 473 if (!check_host((struct sockaddr *)&his_addr)) 474 exit(1); 475 #endif /* TCPWRAPPERS */ 476 } else { 477 addrlen = sizeof(his_addr); 478 if (getpeername(0, (struct sockaddr *)&his_addr, 479 &addrlen) < 0) { 480 /* syslog(LOG_ERR, "getpeername (%s): %m", argv[0]); */ 481 exit(1); 482 } 483 } 484 485 /* set this here so klogin can use it... */ 486 (void)snprintf(ttyline, sizeof(ttyline), "ftp%d", getpid()); 487 488 (void) signal(SIGHUP, sigquit); 489 (void) signal(SIGINT, sigquit); 490 (void) signal(SIGQUIT, sigquit); 491 (void) signal(SIGTERM, sigquit); 492 (void) signal(SIGPIPE, lostconn); 493 (void) signal(SIGCHLD, SIG_IGN); 494 if (signal(SIGURG, myoob) == SIG_ERR) 495 syslog(LOG_ERR, "signal: %m"); 496 497 addrlen = sizeof(ctrl_addr); 498 if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) { 499 syslog(LOG_ERR, "getsockname (%s): %m", argv[0]); 500 exit(1); 501 } 502 if (his_addr.su_family == AF_INET6 503 && IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr)) { 504 #if 1 505 /* 506 * IPv4 control connection arrived to AF_INET6 socket. 507 * I hate to do this, but this is the easiest solution. 508 */ 509 union sockunion tmp_addr; 510 const int off = sizeof(struct in6_addr) - sizeof(struct in_addr); 511 512 tmp_addr = his_addr; 513 memset(&his_addr, 0, sizeof(his_addr)); 514 his_addr.su_sin.sin_family = AF_INET; 515 his_addr.su_sin.sin_len = sizeof(his_addr.su_sin); 516 memcpy(&his_addr.su_sin.sin_addr, 517 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 518 sizeof(his_addr.su_sin.sin_addr)); 519 his_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 520 521 tmp_addr = ctrl_addr; 522 memset(&ctrl_addr, 0, sizeof(ctrl_addr)); 523 ctrl_addr.su_sin.sin_family = AF_INET; 524 ctrl_addr.su_sin.sin_len = sizeof(ctrl_addr.su_sin); 525 memcpy(&ctrl_addr.su_sin.sin_addr, 526 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 527 sizeof(ctrl_addr.su_sin.sin_addr)); 528 ctrl_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 529 #else 530 while (fgets(line, sizeof(line), fd) != NULL) { 531 if ((cp = strchr(line, '\n')) != NULL) 532 *cp = '\0'; 533 lreply(530, "%s", line); 534 } 535 (void) fflush(stdout); 536 (void) fclose(fd); 537 reply(530, 538 "Connection from IPv4 mapped address is not supported."); 539 exit(0); 540 #endif 541 } 542 #ifdef IP_TOS 543 if (his_addr.su_family == AF_INET) { 544 tos = IPTOS_LOWDELAY; 545 if (setsockopt(0, IPPROTO_IP, IP_TOS, (char *)&tos, 546 sizeof(int)) < 0) 547 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 548 } 549 #endif 550 data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1); 551 552 /* Try to handle urgent data inline */ 553 #ifdef SO_OOBINLINE 554 if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, (char *)&on, sizeof(on)) < 0) 555 syslog(LOG_ERR, "setsockopt: %m"); 556 #endif 557 558 #ifdef F_SETOWN 559 if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1) 560 syslog(LOG_ERR, "fcntl F_SETOWN: %m"); 561 #endif 562 dolog((struct sockaddr *)&his_addr); 563 /* 564 * Set up default state 565 */ 566 data = -1; 567 type = TYPE_A; 568 form = FORM_N; 569 stru = STRU_F; 570 mode = MODE_S; 571 tmpline[0] = '\0'; 572 573 /* If logins are disabled, print out the message. */ 574 if ((fp = fopen(_PATH_NOLOGIN, "r")) != NULL) { 575 while (fgets(line, sizeof(line), fp) != NULL) { 576 if ((cp = strchr(line, '\n')) != NULL) 577 *cp = '\0'; 578 lreply(530, "%s", line); 579 } 580 (void) fflush(stdout); 581 (void) fclose(fp); 582 reply(530, "System not available."); 583 exit(0); 584 } 585 if ((fp = fopen(_PATH_FTPWELCOME, "r")) != NULL) { 586 while (fgets(line, sizeof(line), fp) != NULL) { 587 if ((cp = strchr(line, '\n')) != NULL) 588 *cp = '\0'; 589 lreply(220, "%s", line); 590 } 591 (void) fflush(stdout); 592 (void) fclose(fp); 593 /* reply(220,) must follow */ 594 } 595 (void) gethostname(hostname, sizeof(hostname)); 596 597 /* Make sure hostname is fully qualified. */ 598 hp = gethostbyname(hostname); 599 if (hp != NULL) 600 strcpy(hostname, hp->h_name); 601 602 if (multihome) { 603 getnameinfo((struct sockaddr *)&ctrl_addr, ctrl_addr.su_len, 604 dhostname, sizeof(dhostname), NULL, 0, 0); 605 } 606 607 reply(220, "%s FTP server (%s) ready.", 608 (multihome ? dhostname : hostname), version); 609 (void) setjmp(errcatch); 610 for (;;) 611 (void) yyparse(); 612 /* NOTREACHED */ 613 } 614 615 /* 616 * Signal handlers. 617 */ 618 619 static void 620 lostconn(signo) 621 int signo; 622 { 623 624 sigprocmask(SIG_BLOCK, &allsigs, NULL); 625 if (debug) 626 syslog(LOG_DEBUG, "lost connection"); 627 dologout(1); 628 } 629 630 static void 631 sigquit(signo) 632 int signo; 633 { 634 635 sigprocmask(SIG_BLOCK, &allsigs, NULL); 636 syslog(LOG_ERR, "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(name) 647 char *name; 648 { 649 static struct passwd *save; 650 struct passwd *pw; 651 652 if ((pw = getpwnam(name)) == NULL) 653 return (pw); 654 if (save) { 655 memset(save->pw_passwd, 0, strlen(save->pw_passwd)); 656 free(save); 657 } 658 save = pw_dup(pw); 659 if (save == NULL) { 660 perror_reply(421, "Local resource failure: malloc"); 661 dologout(1); 662 /* NOTREACHED */ 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(name) 684 char *name; 685 { 686 char *cp, *shell, *style; 687 char *class = NULL; 688 689 if (logged_in) { 690 if (guest) { 691 reply(530, "Can't change user from guest login."); 692 return; 693 } else if (dochroot) { 694 reply(530, "Can't change user from chroot user."); 695 return; 696 } 697 login_close(lc); 698 lc = NULL; 699 if (as) { 700 auth_close(as); 701 as = NULL; 702 } 703 end_login(); 704 } 705 706 if ((style = strchr(name, ':')) != NULL) 707 *style++ = 0; 708 709 guest = 0; 710 if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) { 711 if (checkuser(_PATH_FTPUSERS, "ftp") || 712 checkuser(_PATH_FTPUSERS, "anonymous")) 713 reply(530, "User %s access denied.", name); 714 else if ((pw = sgetpwnam("ftp")) != NULL) { 715 guest = 1; 716 askpasswd = 1; 717 lc = login_getclass(pw->pw_class); 718 reply(331, 719 "Guest login ok, send your email address as password."); 720 } else 721 reply(530, "User %s unknown.", name); 722 if (!askpasswd && logging) 723 syslog(LOG_NOTICE, 724 "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost); 725 return; 726 } 727 728 shell = _PATH_BSHELL; 729 if ((pw = sgetpwnam(name))) { 730 class = pw->pw_class; 731 if (pw->pw_shell != NULL && *pw->pw_shell != '\0') 732 shell = pw->pw_shell; 733 while ((cp = getusershell()) != NULL) 734 if (strcmp(cp, shell) == 0) 735 break; 736 shell = cp; 737 endusershell(); 738 } 739 740 /* Get login class; if invalid style treat like unknown user. */ 741 lc = login_getclass(class); 742 if (lc && (style = login_getstyle(lc, style, "auth-ftp")) == NULL) { 743 login_close(lc); 744 lc = NULL; 745 pw = NULL; 746 } 747 748 /* Do pre-authentication setup. */ 749 if (lc && ((as = auth_open()) == NULL || 750 auth_setitem(as, AUTHV_STYLE, style) < 0 || 751 auth_setitem(as, AUTHV_NAME, name) < 0 || 752 auth_setitem(as, AUTHV_CLASS, class) < 0 || 753 auth_setoption(as, "login", "yes") < 0 || 754 auth_setoption(as, "notickets", "yes") < 0)) { 755 if (as) { 756 auth_close(as); 757 as = NULL; 758 } 759 login_close(lc); 760 lc = NULL; 761 reply(421, "Local resource failure"); 762 return; 763 } 764 if (logging) 765 strlcpy(curname, name, sizeof(curname)); 766 767 dochroot = (lc && login_getcapbool(lc, "ftp-chroot", 0)) || 768 checkuser(_PATH_FTPCHROOT, name); 769 if (anon_only && !dochroot) { 770 reply(530, "Sorry, only anonymous ftp allowed."); 771 return; 772 } 773 if (pw) { 774 if ((!shell && !dochroot) || checkuser(_PATH_FTPUSERS, name)) { 775 reply(530, "User %s access denied.", name); 776 if (logging) 777 syslog(LOG_NOTICE, 778 "FTP LOGIN REFUSED FROM %s, %s", 779 remotehost, name); 780 pw = NULL; 781 return; 782 } 783 } 784 785 if (as != NULL && (cp = auth_challenge(as)) != NULL) 786 reply(331, cp); 787 else 788 reply(331, "Password required for %s.", name); 789 790 askpasswd = 1; 791 /* 792 * Delay before reading passwd after first failed 793 * attempt to slow down passwd-guessing programs. 794 */ 795 if (login_attempts) 796 sleep((unsigned) login_attempts); 797 } 798 799 /* 800 * Check if a user is in the file "fname" 801 */ 802 static int 803 checkuser(fname, name) 804 char *fname; 805 char *name; 806 { 807 FILE *fp; 808 int found = 0; 809 char *p, line[BUFSIZ]; 810 811 if ((fp = fopen(fname, "r")) != NULL) { 812 while (fgets(line, sizeof(line), fp) != NULL) 813 if ((p = strchr(line, '\n')) != NULL) { 814 *p = '\0'; 815 if (line[0] == '#') 816 continue; 817 if (strcmp(line, name) == 0) { 818 found = 1; 819 break; 820 } 821 } 822 (void) fclose(fp); 823 } 824 return (found); 825 } 826 827 /* 828 * Terminate login as previous user, if any, resetting state; 829 * used when USER command is given or login fails. 830 */ 831 static void 832 end_login() 833 { 834 835 sigprocmask (SIG_BLOCK, &allsigs, NULL); 836 (void) seteuid((uid_t)0); 837 if (logged_in) { 838 ftpdlogwtmp(ttyline, "", ""); 839 if (doutmp) 840 logout(utmp.ut_line); 841 } 842 pw = NULL; 843 /* umask is restored in ftpcmd.y */ 844 setusercontext(NULL, getpwuid(0), (uid_t)0, 845 LOGIN_SETPRIORITY|LOGIN_SETRESOURCES); 846 logged_in = 0; 847 guest = 0; 848 dochroot = 0; 849 } 850 851 void 852 pass(passwd) 853 char *passwd; 854 { 855 int authok, flags; 856 FILE *fp; 857 static char homedir[MAXPATHLEN]; 858 char *motd, *dir, rootdir[MAXPATHLEN]; 859 860 if (logged_in || askpasswd == 0) { 861 reply(503, "Login with USER first."); 862 return; 863 } 864 askpasswd = 0; 865 if (!guest) { /* "ftp" is only account allowed no password */ 866 authok = 0; 867 if (pw == NULL) { 868 useconds_t us; 869 870 /* Sleep between 1 and 3 seconds to emulate a crypt. */ 871 us = arc4random() % 3000000; 872 usleep(us); 873 } else { 874 authok = auth_userresponse(as, passwd, 0); 875 auth_close(as); 876 as = NULL; 877 } 878 if (authok == 0) { 879 reply(530, "Login incorrect."); 880 if (logging) 881 syslog(LOG_NOTICE, 882 "FTP LOGIN FAILED FROM %s, %s", 883 remotehost, curname); 884 pw = NULL; 885 if (login_attempts++ >= 5) { 886 syslog(LOG_NOTICE, 887 "repeated login failures from %s", 888 remotehost); 889 exit(0); 890 } 891 return; 892 } 893 } else if (lc != NULL) { 894 /* Save anonymous' password. */ 895 guestpw = strdup(passwd); 896 if (guestpw == (char *)NULL) 897 fatal("Out of memory"); 898 899 if ((as = auth_open()) == NULL) 900 fatal("Out of memory"); 901 auth_setoption(as, "FTPD_HOST", 902 multihome ? dhostname : hostname); 903 authok = auth_approval(as, lc, pw->pw_name, "ftp"); 904 auth_close(as); 905 as = NULL; 906 if (authok == 0) { 907 syslog(LOG_INFO|LOG_AUTH, 908 "FTP LOGIN FAILED (HOST) as %s: approval failure.", 909 pw->pw_name); 910 reply(530, "Approval failure.\n"); 911 exit(0); 912 } 913 } else { 914 syslog(LOG_INFO|LOG_AUTH, 915 "FTP LOGIN CLASS %s MISSING for %s: approval failure.", 916 pw->pw_class, pw->pw_name); 917 reply(530, "Permission denied.\n"); 918 exit(0); 919 } 920 login_attempts = 0; /* this time successful */ 921 if (setegid((gid_t)pw->pw_gid) < 0) { 922 reply(550, "Can't set gid."); 923 return; 924 } 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 setusercontext(lc, pw, (uid_t)0, flags); 932 933 /* open wtmp before chroot */ 934 ftpdlogwtmp(ttyline, pw->pw_name, remotehost); 935 936 /* open utmp before chroot */ 937 if (doutmp) { 938 memset((void *)&utmp, 0, sizeof(utmp)); 939 (void)time(&utmp.ut_time); 940 (void)strncpy(utmp.ut_name, pw->pw_name, sizeof(utmp.ut_name)); 941 (void)strncpy(utmp.ut_host, remotehost, sizeof(utmp.ut_host)); 942 (void)strncpy(utmp.ut_line, ttyline, sizeof(utmp.ut_line)); 943 login(&utmp); 944 } 945 946 /* open stats file before chroot */ 947 if (guest && (stats == 1) && (statfd < 0)) 948 if ((statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND)) < 0) 949 stats = 0; 950 951 logged_in = 1; 952 953 if ((dir = login_getcapstr(lc, "ftp-dir", NULL, NULL))) { 954 char *newdir; 955 956 newdir = copy_dir(dir, pw); 957 if (newdir == NULL) { 958 perror_reply(421, "Local resource failure: malloc"); 959 dologout(1); 960 /* NOTREACHED */ 961 } 962 free(dir); 963 free(pw->pw_dir); 964 pw->pw_dir = newdir; 965 } 966 967 if (guest || dochroot) { 968 if (multihome && guest) { 969 struct stat ts; 970 971 /* Compute root directory. */ 972 snprintf(rootdir, sizeof(rootdir), "%s/%s", 973 pw->pw_dir, dhostname); 974 if (stat(rootdir, &ts) < 0) { 975 snprintf(rootdir, sizeof(rootdir), "%s/%s", 976 pw->pw_dir, hostname); 977 } 978 } else 979 strcpy(rootdir, pw->pw_dir); 980 } 981 if (guest) { 982 /* 983 * We MUST do a chdir() after the chroot. Otherwise 984 * the old current directory will be accessible as "." 985 * outside the new root! 986 */ 987 if (chroot(rootdir) < 0 || chdir("/") < 0) { 988 reply(550, "Can't set guest privileges."); 989 goto bad; 990 } 991 strcpy(pw->pw_dir, "/"); 992 if (setenv("HOME", "/", 1) == -1) { 993 reply(550, "Can't setup environment."); 994 goto bad; 995 } 996 } else if (dochroot) { 997 if (chroot(rootdir) < 0 || chdir("/") < 0) { 998 reply(550, "Can't change root."); 999 goto bad; 1000 } 1001 strcpy(pw->pw_dir, "/"); 1002 if (setenv("HOME", "/", 1) == -1) { 1003 reply(550, "Can't setup environment."); 1004 goto bad; 1005 } 1006 } else if (chdir(pw->pw_dir) < 0) { 1007 if (chdir("/") < 0) { 1008 reply(530, "User %s: can't change directory to %s.", 1009 pw->pw_name, pw->pw_dir); 1010 goto bad; 1011 } else 1012 lreply(230, "No directory! Logging in with home=/"); 1013 } 1014 if (seteuid((uid_t)pw->pw_uid) < 0) { 1015 reply(550, "Can't set uid."); 1016 goto bad; 1017 } 1018 sigprocmask(SIG_UNBLOCK, &allsigs, NULL); 1019 1020 /* 1021 * Set home directory so that use of ~ (tilde) works correctly. 1022 */ 1023 if (getcwd(homedir, MAXPATHLEN) != NULL) { 1024 if (setenv("HOME", homedir, 1) == -1) { 1025 reply(550, "Can't setup environment."); 1026 goto bad; 1027 } 1028 } 1029 1030 /* 1031 * Display a login message, if it exists. 1032 * N.B. reply(230,) must follow the message. 1033 */ 1034 motd = login_getcapstr(lc, "welcome", NULL, NULL); 1035 if ((fp = fopen(motd ? motd : _PATH_FTPLOGINMESG, "r")) != NULL) { 1036 char *cp, line[LINE_MAX]; 1037 1038 while (fgets(line, sizeof(line), fp) != NULL) { 1039 if ((cp = strchr(line, '\n')) != NULL) 1040 *cp = '\0'; 1041 lreply(230, "%s", line); 1042 } 1043 (void) fflush(stdout); 1044 (void) fclose(fp); 1045 } 1046 if (motd != NULL) 1047 free(motd); 1048 if (guest) { 1049 if (ident != NULL) 1050 free(ident); 1051 ident = strdup(passwd); 1052 if (ident == NULL) 1053 fatal("Ran out of memory."); 1054 reply(230, "Guest login ok, access restrictions apply."); 1055 #ifdef HASSETPROCTITLE 1056 snprintf(proctitle, sizeof(proctitle), 1057 "%s: anonymous/%.*s", remotehost, 1058 (int)(sizeof(proctitle) - sizeof(remotehost) - 1059 sizeof(": anonymous/")), passwd); 1060 setproctitle("%s", proctitle); 1061 #endif /* HASSETPROCTITLE */ 1062 if (logging) 1063 syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s", 1064 remotehost, passwd); 1065 } else { 1066 reply(230, "User %s logged in.", pw->pw_name); 1067 #ifdef HASSETPROCTITLE 1068 snprintf(proctitle, sizeof(proctitle), 1069 "%s: %s", remotehost, pw->pw_name); 1070 setproctitle("%s", proctitle); 1071 #endif /* HASSETPROCTITLE */ 1072 if (logging) 1073 syslog(LOG_INFO, "FTP LOGIN FROM %s as %s", 1074 remotehost, pw->pw_name); 1075 } 1076 login_close(lc); 1077 lc = NULL; 1078 return; 1079 bad: 1080 /* Forget all about it... */ 1081 login_close(lc); 1082 lc = NULL; 1083 end_login(); 1084 } 1085 1086 void 1087 retrieve(cmd, name) 1088 char *cmd, *name; 1089 { 1090 FILE *fin, *dout; 1091 struct stat st; 1092 int (*closefunc) __P((FILE *)); 1093 time_t start; 1094 1095 if (cmd == 0) { 1096 fin = fopen(name, "r"), closefunc = fclose; 1097 st.st_size = 0; 1098 } else { 1099 char line[BUFSIZ]; 1100 1101 (void) snprintf(line, sizeof(line), cmd, name); 1102 name = line; 1103 fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose; 1104 st.st_size = -1; 1105 st.st_blksize = BUFSIZ; 1106 } 1107 if (fin == NULL) { 1108 if (errno != 0) { 1109 perror_reply(550, name); 1110 if (cmd == 0) { 1111 LOGCMD("get", name); 1112 } 1113 } 1114 return; 1115 } 1116 byte_count = -1; 1117 if (cmd == 0 && (fstat(fileno(fin), &st) < 0 || !S_ISREG(st.st_mode))) { 1118 reply(550, "%s: not a plain file.", name); 1119 goto done; 1120 } 1121 if (restart_point) { 1122 if (type == TYPE_A) { 1123 off_t i, n; 1124 int c; 1125 1126 n = restart_point; 1127 i = 0; 1128 while (i++ < n) { 1129 if ((c=getc(fin)) == EOF) { 1130 perror_reply(550, name); 1131 goto done; 1132 } 1133 if (c == '\n') 1134 i++; 1135 } 1136 } else if (lseek(fileno(fin), restart_point, SEEK_SET) < 0) { 1137 perror_reply(550, name); 1138 goto done; 1139 } 1140 } 1141 dout = dataconn(name, st.st_size, "w"); 1142 if (dout == NULL) 1143 goto done; 1144 time(&start); 1145 send_data(fin, dout, st.st_blksize, st.st_size, 1146 (restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode))); 1147 if ((cmd == 0) && stats) 1148 logxfer(name, byte_count, start); 1149 (void) fclose(dout); 1150 data = -1; 1151 done: 1152 if (pdata >= 0) 1153 (void) close(pdata); 1154 pdata = -1; 1155 if (cmd == 0) 1156 LOGBYTES("get", name, byte_count); 1157 (*closefunc)(fin); 1158 } 1159 1160 void 1161 store(name, mode, unique) 1162 char *name, *mode; 1163 int unique; 1164 { 1165 FILE *fout, *din; 1166 int (*closefunc) __P((FILE *)); 1167 struct stat st; 1168 int fd; 1169 1170 if (restart_point && *mode != 'a') 1171 mode = "r+"; 1172 1173 if (unique && stat(name, &st) == 0) { 1174 char *nam; 1175 1176 fd = guniquefd(name, &nam); 1177 if (fd == -1) { 1178 LOGCMD(*mode == 'w' ? "put" : "append", name); 1179 return; 1180 } 1181 name = nam; 1182 fout = fdopen(fd, mode); 1183 } else 1184 fout = fopen(name, mode); 1185 1186 closefunc = fclose; 1187 if (fout == NULL) { 1188 perror_reply(553, name); 1189 LOGCMD(*mode == 'w' ? "put" : "append", name); 1190 return; 1191 } 1192 byte_count = -1; 1193 if (restart_point) { 1194 if (type == TYPE_A) { 1195 off_t i, n; 1196 int c; 1197 1198 n = restart_point; 1199 i = 0; 1200 while (i++ < n) { 1201 if ((c=getc(fout)) == EOF) { 1202 perror_reply(550, name); 1203 goto done; 1204 } 1205 if (c == '\n') 1206 i++; 1207 } 1208 /* 1209 * We must do this seek to "current" position 1210 * because we are changing from reading to 1211 * writing. 1212 */ 1213 if (fseek(fout, 0L, SEEK_CUR) < 0) { 1214 perror_reply(550, name); 1215 goto done; 1216 } 1217 } else if (lseek(fileno(fout), restart_point, SEEK_SET) < 0) { 1218 perror_reply(550, name); 1219 goto done; 1220 } 1221 } 1222 din = dataconn(name, (off_t)-1, "r"); 1223 if (din == NULL) 1224 goto done; 1225 if (receive_data(din, fout) == 0) { 1226 if (unique) 1227 reply(226, "Transfer complete (unique file name:%s).", 1228 name); 1229 else 1230 reply(226, "Transfer complete."); 1231 } 1232 (void) fclose(din); 1233 data = -1; 1234 pdata = -1; 1235 done: 1236 LOGBYTES(*mode == 'w' ? "put" : "append", name, byte_count); 1237 (*closefunc)(fout); 1238 } 1239 1240 static FILE * 1241 getdatasock(mode) 1242 char *mode; 1243 { 1244 int on = 1, s, t, tries; 1245 1246 if (data >= 0) 1247 return (fdopen(data, mode)); 1248 sigprocmask (SIG_BLOCK, &allsigs, NULL); 1249 (void) seteuid((uid_t)0); 1250 s = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 1251 if (s < 0) 1252 goto bad; 1253 if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, 1254 (char *) &on, sizeof(on)) < 0) 1255 goto bad; 1256 /* anchor socket to avoid multi-homing problems */ 1257 data_source = ctrl_addr; 1258 data_source.su_port = htons(20); /* ftp-data port */ 1259 for (tries = 1; ; tries++) { 1260 if (bind(s, (struct sockaddr *)&data_source, 1261 data_source.su_len) >= 0) 1262 break; 1263 if (errno != EADDRINUSE || tries > 10) 1264 goto bad; 1265 sleep(tries); 1266 } 1267 (void) seteuid((uid_t)pw->pw_uid); 1268 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1269 1270 #ifdef IP_TOS 1271 if (ctrl_addr.su_family == AF_INET) { 1272 on = IPTOS_THROUGHPUT; 1273 if (setsockopt(s, IPPROTO_IP, IP_TOS, (char *)&on, 1274 sizeof(int)) < 0) 1275 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 1276 } 1277 #endif 1278 #ifdef TCP_NOPUSH 1279 /* 1280 * Turn off push flag to keep sender TCP from sending short packets 1281 * at the boundaries of each write(). Should probably do a SO_SNDBUF 1282 * to set the send buffer size as well, but that may not be desirable 1283 * in heavy-load situations. 1284 */ 1285 on = 1; 1286 if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, (char *)&on, sizeof(on)) < 0) 1287 syslog(LOG_WARNING, "setsockopt (TCP_NOPUSH): %m"); 1288 #endif 1289 #ifdef SO_SNDBUF 1290 on = 65536; 1291 if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, (char *)&on, sizeof(on)) < 0) 1292 syslog(LOG_WARNING, "setsockopt (SO_SNDBUF): %m"); 1293 #endif 1294 1295 return (fdopen(s, mode)); 1296 bad: 1297 /* Return the real value of errno (close may change it) */ 1298 t = errno; 1299 (void) seteuid((uid_t)pw->pw_uid); 1300 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1301 (void) close(s); 1302 errno = t; 1303 return (NULL); 1304 } 1305 1306 static FILE * 1307 dataconn(name, size, mode) 1308 char *name; 1309 off_t size; 1310 char *mode; 1311 { 1312 char sizebuf[32]; 1313 FILE *file; 1314 int retry = 0; 1315 in_port_t *p; 1316 char *fa, *ha; 1317 int alen; 1318 1319 file_size = size; 1320 byte_count = 0; 1321 if (size != (off_t) -1) { 1322 (void) snprintf(sizebuf, sizeof(sizebuf), " (%qd bytes)", 1323 size); 1324 } else 1325 sizebuf[0] = '\0'; 1326 if (pdata >= 0) { 1327 union sockunion from; 1328 int s, fromlen = sizeof(from); 1329 1330 signal (SIGALRM, toolong); 1331 (void) alarm ((unsigned) timeout); 1332 s = accept(pdata, (struct sockaddr *)&from, &fromlen); 1333 (void) alarm (0); 1334 if (s < 0) { 1335 reply(425, "Can't open data connection."); 1336 (void) close(pdata); 1337 pdata = -1; 1338 return (NULL); 1339 } 1340 switch (from.su_family) { 1341 case AF_INET: 1342 p = (in_port_t *)&from.su_sin.sin_port; 1343 fa = (u_char *)&from.su_sin.sin_addr; 1344 ha = (u_char *)&his_addr.su_sin.sin_addr; 1345 alen = sizeof(struct in_addr); 1346 break; 1347 case AF_INET6: 1348 p = (in_port_t *)&from.su_sin6.sin6_port; 1349 fa = (u_char *)&from.su_sin6.sin6_addr; 1350 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1351 alen = sizeof(struct in6_addr); 1352 break; 1353 default: 1354 perror_reply(425, "Can't build data connection"); 1355 (void) close(pdata); 1356 (void) close(s); 1357 pdata = -1; 1358 return (NULL); 1359 } 1360 if (from.su_family != his_addr.su_family || 1361 ntohs(*p) < IPPORT_RESERVED) { 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 (portcheck && memcmp(fa, ha, alen) != 0) { 1369 perror_reply(435, "Can't build data connection"); 1370 (void) close(pdata); 1371 (void) close(s); 1372 pdata = -1; 1373 return (NULL); 1374 } 1375 (void) close(pdata); 1376 pdata = s; 1377 reply(150, "Opening %s mode data connection for '%s'%s.", 1378 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1379 return (fdopen(pdata, mode)); 1380 } 1381 if (data >= 0) { 1382 reply(125, "Using existing data connection for '%s'%s.", 1383 name, sizebuf); 1384 usedefault = 1; 1385 return (fdopen(data, mode)); 1386 } 1387 if (usedefault) 1388 data_dest = his_addr; 1389 usedefault = 1; 1390 file = getdatasock(mode); 1391 if (file == NULL) { 1392 char hbuf[MAXHOSTNAMELEN], pbuf[10]; 1393 1394 getnameinfo((struct sockaddr *)&data_source, data_source.su_len, 1395 hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), 1396 NI_NUMERICHOST | NI_NUMERICSERV); 1397 reply(425, "Can't create data socket (%s,%s): %s.", 1398 hbuf, pbuf, strerror(errno)); 1399 return (NULL); 1400 } 1401 data = fileno(file); 1402 1403 /* 1404 * attempt to connect to reserved port on client machine; 1405 * this looks like an attack 1406 */ 1407 switch (data_dest.su_family) { 1408 case AF_INET: 1409 p = (in_port_t *)&data_dest.su_sin.sin_port; 1410 fa = (u_char *)&data_dest.su_sin.sin_addr; 1411 ha = (u_char *)&his_addr.su_sin.sin_addr; 1412 alen = sizeof(struct in_addr); 1413 break; 1414 case AF_INET6: 1415 p = (in_port_t *)&data_dest.su_sin6.sin6_port; 1416 fa = (u_char *)&data_dest.su_sin6.sin6_addr; 1417 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1418 alen = sizeof(struct in6_addr); 1419 break; 1420 default: 1421 perror_reply(425, "Can't build data connection"); 1422 (void) fclose(file); 1423 pdata = -1; 1424 return (NULL); 1425 } 1426 if (data_dest.su_family != his_addr.su_family || 1427 ntohs(*p) < IPPORT_RESERVED || ntohs(*p) == 2049) { /* XXX */ 1428 perror_reply(425, "Can't build data connection"); 1429 (void) fclose(file); 1430 data = -1; 1431 return NULL; 1432 } 1433 if (portcheck && memcmp(fa, ha, alen) != 0) { 1434 perror_reply(435, "Can't build data connection"); 1435 (void) fclose(file); 1436 data = -1; 1437 return NULL; 1438 } 1439 while (connect(data, (struct sockaddr *)&data_dest, 1440 data_dest.su_len) < 0) { 1441 if (errno == EADDRINUSE && retry < swaitmax) { 1442 sleep((unsigned) swaitint); 1443 retry += swaitint; 1444 continue; 1445 } 1446 perror_reply(425, "Can't build data connection"); 1447 (void) fclose(file); 1448 data = -1; 1449 return (NULL); 1450 } 1451 reply(150, "Opening %s mode data connection for '%s'%s.", 1452 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1453 return (file); 1454 } 1455 1456 /* 1457 * Tranfer the contents of "instr" to "outstr" peer using the appropriate 1458 * encapsulation of the data subject to Mode, Structure, and Type. 1459 * 1460 * NB: Form isn't handled. 1461 */ 1462 static void 1463 send_data(instr, outstr, blksize, filesize, isreg) 1464 FILE *instr, *outstr; 1465 off_t blksize; 1466 off_t filesize; 1467 int isreg; 1468 { 1469 int c, cnt, filefd, netfd; 1470 char *buf, *bp; 1471 size_t len; 1472 1473 transflag++; 1474 if (setjmp(urgcatch)) { 1475 transflag = 0; 1476 return; 1477 } 1478 switch (type) { 1479 1480 case TYPE_A: 1481 while ((c = getc(instr)) != EOF) { 1482 byte_count++; 1483 if (c == '\n') { 1484 if (ferror(outstr)) 1485 goto data_err; 1486 (void) putc('\r', outstr); 1487 } 1488 (void) putc(c, outstr); 1489 } 1490 fflush(outstr); 1491 transflag = 0; 1492 if (ferror(instr)) 1493 goto file_err; 1494 if (ferror(outstr)) 1495 goto data_err; 1496 reply(226, "Transfer complete."); 1497 return; 1498 1499 case TYPE_I: 1500 case TYPE_L: 1501 /* 1502 * isreg is only set if we are not doing restart and we 1503 * are sending a regular file 1504 */ 1505 netfd = fileno(outstr); 1506 filefd = fileno(instr); 1507 1508 if (isreg && filesize < (off_t)16 * 1024 * 1024) { 1509 buf = mmap(0, filesize, PROT_READ, MAP_SHARED, filefd, 1510 (off_t)0); 1511 if (buf == MAP_FAILED) { 1512 syslog(LOG_WARNING, "mmap(%lu): %m", 1513 (unsigned long)filesize); 1514 goto oldway; 1515 } 1516 bp = buf; 1517 len = filesize; 1518 do { 1519 cnt = write(netfd, bp, len); 1520 len -= cnt; 1521 bp += cnt; 1522 if (cnt > 0) byte_count += cnt; 1523 } while(cnt > 0 && len > 0); 1524 1525 transflag = 0; 1526 munmap(buf, (size_t)filesize); 1527 if (cnt < 0) 1528 goto data_err; 1529 reply(226, "Transfer complete."); 1530 return; 1531 } 1532 1533 oldway: 1534 if ((buf = malloc((u_int)blksize)) == NULL) { 1535 transflag = 0; 1536 perror_reply(451, "Local resource failure: malloc"); 1537 return; 1538 } 1539 1540 while ((cnt = read(filefd, buf, (u_int)blksize)) > 0 && 1541 write(netfd, buf, cnt) == cnt) 1542 byte_count += cnt; 1543 transflag = 0; 1544 (void)free(buf); 1545 if (cnt != 0) { 1546 if (cnt < 0) 1547 goto file_err; 1548 goto data_err; 1549 } 1550 reply(226, "Transfer complete."); 1551 return; 1552 default: 1553 transflag = 0; 1554 reply(550, "Unimplemented TYPE %d in send_data", type); 1555 return; 1556 } 1557 1558 data_err: 1559 transflag = 0; 1560 perror_reply(426, "Data connection"); 1561 return; 1562 1563 file_err: 1564 transflag = 0; 1565 perror_reply(551, "Error on input file"); 1566 } 1567 1568 /* 1569 * Transfer data from peer to "outstr" using the appropriate encapulation of 1570 * the data subject to Mode, Structure, and Type. 1571 * 1572 * N.B.: Form isn't handled. 1573 */ 1574 static int 1575 receive_data(instr, outstr) 1576 FILE *instr, *outstr; 1577 { 1578 int c; 1579 int cnt; 1580 volatile int bare_lfs = 0; 1581 char buf[BUFSIZ]; 1582 1583 transflag++; 1584 if (setjmp(urgcatch)) { 1585 transflag = 0; 1586 return (-1); 1587 } 1588 switch (type) { 1589 1590 case TYPE_I: 1591 case TYPE_L: 1592 signal (SIGALRM, lostconn); 1593 1594 do { 1595 (void) alarm ((unsigned) timeout); 1596 cnt = read(fileno(instr), buf, sizeof(buf)); 1597 (void) alarm (0); 1598 1599 if (cnt > 0) { 1600 if (write(fileno(outstr), buf, cnt) != cnt) 1601 goto file_err; 1602 byte_count += cnt; 1603 } 1604 } while (cnt > 0); 1605 if (cnt < 0) 1606 goto data_err; 1607 transflag = 0; 1608 return (0); 1609 1610 case TYPE_E: 1611 reply(553, "TYPE E not implemented."); 1612 transflag = 0; 1613 return (-1); 1614 1615 case TYPE_A: 1616 while ((c = getc(instr)) != EOF) { 1617 byte_count++; 1618 if (c == '\n') 1619 bare_lfs++; 1620 while (c == '\r') { 1621 if (ferror(outstr)) 1622 goto data_err; 1623 if ((c = getc(instr)) != '\n') { 1624 (void) putc ('\r', outstr); 1625 if (c == '\0' || c == EOF) 1626 goto contin2; 1627 } 1628 } 1629 (void) putc(c, outstr); 1630 contin2: ; 1631 } 1632 fflush(outstr); 1633 if (ferror(instr)) 1634 goto data_err; 1635 if (ferror(outstr)) 1636 goto file_err; 1637 transflag = 0; 1638 if (bare_lfs) { 1639 lreply(226, 1640 "WARNING! %d bare linefeeds received in ASCII mode", 1641 bare_lfs); 1642 printf(" File may not have transferred correctly.\r\n"); 1643 } 1644 return (0); 1645 default: 1646 reply(550, "Unimplemented TYPE %d in receive_data", type); 1647 transflag = 0; 1648 return (-1); 1649 } 1650 1651 data_err: 1652 transflag = 0; 1653 perror_reply(426, "Data Connection"); 1654 return (-1); 1655 1656 file_err: 1657 transflag = 0; 1658 perror_reply(452, "Error writing file"); 1659 return (-1); 1660 } 1661 1662 void 1663 statfilecmd(filename) 1664 char *filename; 1665 { 1666 FILE *fin; 1667 int c; 1668 int atstart; 1669 char line[LINE_MAX]; 1670 1671 (void)snprintf(line, sizeof(line), "/bin/ls -lgA %s", filename); 1672 fin = ftpd_popen(line, "r"); 1673 lreply(211, "status of %s:", filename); 1674 atstart = 1; 1675 while ((c = getc(fin)) != EOF) { 1676 if (c == '\n') { 1677 if (ferror(stdout)){ 1678 perror_reply(421, "control connection"); 1679 (void) ftpd_pclose(fin); 1680 dologout(1); 1681 /* NOTREACHED */ 1682 } 1683 if (ferror(fin)) { 1684 perror_reply(551, filename); 1685 (void) ftpd_pclose(fin); 1686 return; 1687 } 1688 (void) putc('\r', stdout); 1689 } 1690 if (atstart && isdigit(c)) 1691 (void) putc(' ', stdout); 1692 (void) putc(c, stdout); 1693 atstart = (c == '\n'); 1694 } 1695 (void) ftpd_pclose(fin); 1696 reply(211, "End of Status"); 1697 } 1698 1699 void 1700 statcmd() 1701 { 1702 union sockunion *su; 1703 u_char *a, *p; 1704 char hbuf[MAXHOSTNAMELEN]; 1705 int ispassive; 1706 1707 lreply(211, "%s FTP server status:", hostname, version); 1708 printf(" %s\r\n", version); 1709 getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len, 1710 hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST); 1711 printf(" Connected to %s", remotehost); 1712 if (strcmp(remotehost, hbuf) != 0) 1713 printf(" (%s)", hbuf); 1714 printf("\r\n"); 1715 if (logged_in) { 1716 if (guest) 1717 printf(" Logged in anonymously\r\n"); 1718 else 1719 printf(" Logged in as %s\r\n", pw->pw_name); 1720 } else if (askpasswd) 1721 printf(" Waiting for password\r\n"); 1722 else 1723 printf(" Waiting for user name\r\n"); 1724 printf(" TYPE: %s", typenames[type]); 1725 if (type == TYPE_A || type == TYPE_E) 1726 printf(", FORM: %s", formnames[form]); 1727 if (type == TYPE_L) 1728 #if NBBY == 8 1729 printf(" %d", NBBY); 1730 #else 1731 printf(" %d", bytesize); /* need definition! */ 1732 #endif 1733 printf("; STRUcture: %s; transfer MODE: %s\r\n", 1734 strunames[stru], modenames[mode]); 1735 ispassive = 0; 1736 if (data != -1) 1737 printf(" Data connection open\r\n"); 1738 else if (pdata != -1) { 1739 printf(" in Passive mode\r\n"); 1740 su = (union sockunion *)&pasv_addr; 1741 ispassive++; 1742 goto printaddr; 1743 } else if (usedefault == 0) { 1744 su = (union sockunion *)&data_dest; 1745 printaddr: 1746 /* PASV/PORT */ 1747 if (su->su_family == AF_INET) { 1748 if (ispassive) 1749 printf("211- PASV "); 1750 else 1751 printf("211- PORT "); 1752 a = (u_char *) &su->su_sin.sin_addr; 1753 p = (u_char *) &su->su_sin.sin_port; 1754 printf("(%u,%u,%u,%u,%u,%u)\r\n", 1755 a[0], a[1], a[2], a[3], 1756 p[0], p[1]); 1757 } 1758 1759 /* LPSV/LPRT */ 1760 { 1761 int alen, af, i; 1762 1763 alen = 0; 1764 switch (su->su_family) { 1765 case AF_INET: 1766 a = (u_char *) &su->su_sin.sin_addr; 1767 p = (u_char *) &su->su_sin.sin_port; 1768 alen = sizeof(su->su_sin.sin_addr); 1769 af = 4; 1770 break; 1771 case AF_INET6: 1772 a = (u_char *) &su->su_sin6.sin6_addr; 1773 p = (u_char *) &su->su_sin6.sin6_port; 1774 alen = sizeof(su->su_sin6.sin6_addr); 1775 af = 6; 1776 break; 1777 default: 1778 af = 0; 1779 break; 1780 } 1781 if (af) { 1782 if (ispassive) 1783 printf("211- LPSV "); 1784 else 1785 printf("211- LPRT "); 1786 printf("(%u,%u", af, alen); 1787 for (i = 0; i < alen; i++) 1788 printf(",%u", a[i]); 1789 printf(",%u,%u,%u)\r\n", 2, p[0], p[1]); 1790 } 1791 } 1792 1793 /* EPRT/EPSV */ 1794 { 1795 u_char af; 1796 1797 switch (su->su_family) { 1798 case AF_INET: 1799 af = 1; 1800 break; 1801 case AF_INET6: 1802 af = 2; 1803 break; 1804 default: 1805 af = 0; 1806 break; 1807 } 1808 if (af) { 1809 char hbuf[MAXHOSTNAMELEN], pbuf[10]; 1810 if (getnameinfo((struct sockaddr *)su, su->su_len, 1811 hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), 1812 NI_NUMERICHOST) == 0) { 1813 if (ispassive) 1814 printf("211- EPSV "); 1815 else 1816 printf("211- EPRT "); 1817 printf("(|%u|%s|%s|)\r\n", 1818 af, hbuf, pbuf); 1819 } 1820 } 1821 } 1822 } else 1823 printf(" No data connection\r\n"); 1824 reply(211, "End of status"); 1825 } 1826 1827 void 1828 fatal(s) 1829 char *s; 1830 { 1831 1832 reply(451, "Error in server: %s\n", s); 1833 reply(221, "Closing connection due to server error."); 1834 dologout(0); 1835 /* NOTREACHED */ 1836 } 1837 1838 void 1839 #ifdef __STDC__ 1840 reply(int n, const char *fmt, ...) 1841 #else 1842 reply(n, fmt, va_alist) 1843 int n; 1844 char *fmt; 1845 va_dcl 1846 #endif 1847 { 1848 char *buf, *p, *next; 1849 va_list ap; 1850 #ifdef __STDC__ 1851 va_start(ap, fmt); 1852 #else 1853 va_start(ap); 1854 #endif 1855 if (vasprintf(&buf, fmt, ap) == -1 || buf == NULL) { 1856 printf("412 Local resource failure: malloc\r\n"); 1857 fflush(stdout); 1858 dologout(1); 1859 } 1860 next = buf; 1861 while ((p = strsep(&next, "\n\r"))) { 1862 printf("%d%s %s\r\n", n, (next != '\0') ? "-" : "", p); 1863 if (debug) 1864 syslog(LOG_DEBUG, "<--- %d%s %s", n, 1865 (next != '\0') ? "-" : "", p); 1866 } 1867 (void)fflush(stdout); 1868 free(buf); 1869 } 1870 1871 void 1872 #ifdef __STDC__ 1873 lreply(int n, const char *fmt, ...) 1874 #else 1875 lreply(n, fmt, va_alist) 1876 int n; 1877 char *fmt; 1878 va_dcl 1879 #endif 1880 { 1881 va_list ap; 1882 #ifdef __STDC__ 1883 va_start(ap, fmt); 1884 #else 1885 va_start(ap); 1886 #endif 1887 (void)printf("%d- ", n); 1888 (void)vprintf(fmt, ap); 1889 va_end(ap); 1890 (void)printf("\r\n"); 1891 (void)fflush(stdout); 1892 if (debug) { 1893 #ifdef __STDC__ 1894 va_start(ap, fmt); 1895 #else 1896 va_start(ap); 1897 #endif 1898 syslog(LOG_DEBUG, "<--- %d- ", n); 1899 vsyslog(LOG_DEBUG, fmt, ap); 1900 va_end(ap); 1901 } 1902 } 1903 1904 static void 1905 ack(s) 1906 char *s; 1907 { 1908 1909 reply(250, "%s command successful.", s); 1910 } 1911 1912 void 1913 nack(s) 1914 char *s; 1915 { 1916 1917 reply(502, "%s command not implemented.", s); 1918 } 1919 1920 /* ARGSUSED */ 1921 void 1922 yyerror(s) 1923 char *s; 1924 { 1925 char *cp; 1926 1927 if ((cp = strchr(cbuf,'\n'))) 1928 *cp = '\0'; 1929 reply(500, "'%s': command not understood.", cbuf); 1930 } 1931 1932 void 1933 delete(name) 1934 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(path) 1960 char *path; 1961 { 1962 FILE *message; 1963 1964 if (chdir(path) < 0) 1965 perror_reply(550, path); 1966 else { 1967 if ((message = fopen(_PATH_CWDMESG, "r")) != NULL) { 1968 char *cp, line[LINE_MAX]; 1969 1970 while (fgets(line, sizeof(line), message) != NULL) { 1971 if ((cp = strchr(line, '\n')) != NULL) 1972 *cp = '\0'; 1973 lreply(250, "%s", line); 1974 } 1975 (void) fflush(stdout); 1976 (void) fclose(message); 1977 } 1978 ack("CWD"); 1979 } 1980 } 1981 1982 void 1983 replydirname(name, message) 1984 const char *name, *message; 1985 { 1986 char *p, *ep; 1987 char npath[MAXPATHLEN * 2]; 1988 1989 p = npath; 1990 ep = &npath[sizeof(npath) - 1]; 1991 while (*name) { 1992 if (*name == '"') { 1993 if (ep - p < 2) 1994 break; 1995 *p++ = *name++; 1996 *p++ = '"'; 1997 } else { 1998 if (ep - p < 1) 1999 break; 2000 *p++ = *name++; 2001 } 2002 } 2003 *p = '\0'; 2004 reply(257, "\"%s\" %s", npath, message); 2005 } 2006 2007 void 2008 makedir(name) 2009 char *name; 2010 { 2011 2012 LOGCMD("mkdir", name); 2013 if (mkdir(name, 0777) < 0) 2014 perror_reply(550, name); 2015 else 2016 replydirname(name, "directory created."); 2017 } 2018 2019 void 2020 removedir(name) 2021 char *name; 2022 { 2023 2024 LOGCMD("rmdir", name); 2025 if (rmdir(name) < 0) 2026 perror_reply(550, name); 2027 else 2028 ack("RMD"); 2029 } 2030 2031 void 2032 pwd() 2033 { 2034 char path[MAXPATHLEN]; 2035 2036 if (getcwd(path, sizeof(path)) == NULL) 2037 reply(550, "Can't get current directory: %s.", strerror(errno)); 2038 else 2039 replydirname(path, "is current directory."); 2040 } 2041 2042 char * 2043 renamefrom(name) 2044 char *name; 2045 { 2046 struct stat st; 2047 2048 if (stat(name, &st) < 0) { 2049 perror_reply(550, name); 2050 return ((char *)0); 2051 } 2052 reply(350, "File exists, ready for destination name"); 2053 return (name); 2054 } 2055 2056 void 2057 renamecmd(from, to) 2058 char *from, *to; 2059 { 2060 2061 LOGCMD2("rename", from, to); 2062 if (rename(from, to) < 0) 2063 perror_reply(550, "rename"); 2064 else 2065 ack("RNTO"); 2066 } 2067 2068 static void 2069 dolog(sa) 2070 struct sockaddr *sa; 2071 { 2072 char hbuf[sizeof(remotehost)]; 2073 2074 getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), NULL, 0, 0); 2075 (void) strlcpy(remotehost, hbuf, sizeof(remotehost)); 2076 2077 #ifdef HASSETPROCTITLE 2078 snprintf(proctitle, sizeof(proctitle), "%s: connected", remotehost); 2079 setproctitle("%s", proctitle); 2080 #endif /* HASSETPROCTITLE */ 2081 2082 if (logging) 2083 syslog(LOG_INFO, "connection from %s", remotehost); 2084 } 2085 2086 /* 2087 * Record logout in wtmp file 2088 * and exit with supplied status. 2089 */ 2090 void 2091 dologout(status) 2092 int status; 2093 { 2094 2095 transflag = 0; 2096 2097 if (logged_in) { 2098 sigprocmask(SIG_BLOCK, &allsigs, NULL); 2099 (void) seteuid((uid_t)0); 2100 ftpdlogwtmp(ttyline, "", ""); 2101 if (doutmp) 2102 logout(utmp.ut_line); 2103 } 2104 /* beware of flushing buffers after a SIGPIPE */ 2105 _exit(status); 2106 } 2107 2108 static void 2109 myoob(signo) 2110 int signo; 2111 { 2112 char *cp; 2113 int save_errno = errno; 2114 2115 /* only process if transfer occurring */ 2116 if (!transflag) 2117 return; 2118 cp = tmpline; 2119 if (getline(cp, 7, stdin) == NULL) { 2120 reply(221, "You could at least say goodbye."); 2121 dologout(0); 2122 } 2123 upper(cp); 2124 if (strcmp(cp, "ABOR\r\n") == 0) { 2125 tmpline[0] = '\0'; 2126 reply(426, "Transfer aborted. Data connection closed."); 2127 reply(226, "Abort successful"); 2128 longjmp(urgcatch, 1); 2129 } 2130 if (strcmp(cp, "STAT\r\n") == 0) { 2131 tmpline[0] = '\0'; 2132 if (file_size != (off_t) -1) 2133 reply(213, "Status: %qd of %qd bytes transferred", 2134 byte_count, file_size); 2135 else 2136 reply(213, "Status: %qd bytes transferred", byte_count); 2137 } 2138 errno = save_errno; 2139 } 2140 2141 /* 2142 * Note: a response of 425 is not mentioned as a possible response to 2143 * the PASV command in RFC959. However, it has been blessed as 2144 * a legitimate response by Jon Postel in a telephone conversation 2145 * with Rick Adams on 25 Jan 89. 2146 */ 2147 void 2148 passive() 2149 { 2150 int len, on; 2151 u_char *p, *a; 2152 2153 if (pw == NULL) { 2154 reply(530, "Please login with USER and PASS"); 2155 return; 2156 } 2157 if (pdata >= 0) 2158 close(pdata); 2159 /* 2160 * XXX 2161 * At this point, it would be nice to have an algorithm that 2162 * inserted a growing delay in an attack scenario. Such a thing 2163 * would look like continual passive sockets being opened, but 2164 * nothing serious being done with them. They're not used to 2165 * move data; the entire attempt is just to use tcp FIN_WAIT 2166 * resources. 2167 */ 2168 pdata = socket(AF_INET, SOCK_STREAM, 0); 2169 if (pdata < 0) { 2170 perror_reply(425, "Can't open passive connection"); 2171 return; 2172 } 2173 2174 #ifdef IP_PORTRANGE 2175 on = high_data_ports ? IP_PORTRANGE_HIGH : IP_PORTRANGE_DEFAULT; 2176 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2177 (char *)&on, sizeof(on)) < 0) 2178 goto pasv_error; 2179 #endif 2180 2181 pasv_addr = ctrl_addr; 2182 pasv_addr.su_sin.sin_port = 0; 2183 if (bind(pdata, (struct sockaddr *)&pasv_addr, 2184 pasv_addr.su_len) < 0) 2185 goto pasv_error; 2186 2187 len = sizeof(pasv_addr); 2188 if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0) 2189 goto pasv_error; 2190 if (listen(pdata, 1) < 0) 2191 goto pasv_error; 2192 a = (u_char *) &pasv_addr.su_sin.sin_addr; 2193 p = (u_char *) &pasv_addr.su_sin.sin_port; 2194 2195 reply(227, "Entering Passive Mode (%u,%u,%u,%u,%u,%u)", a[0], 2196 a[1], a[2], a[3], p[0], p[1]); 2197 return; 2198 2199 pasv_error: 2200 (void) seteuid((uid_t)pw->pw_uid); 2201 (void) close(pdata); 2202 pdata = -1; 2203 perror_reply(425, "Can't open passive connection"); 2204 return; 2205 } 2206 2207 /* 2208 * convert protocol identifier to/from AF 2209 */ 2210 int 2211 lpsvproto2af(int proto) 2212 { 2213 2214 switch (proto) { 2215 case 4: return AF_INET; 2216 #ifdef INET6 2217 case 6: return AF_INET6; 2218 #endif 2219 default: return -1; 2220 } 2221 } 2222 2223 int 2224 af2lpsvproto(int af) 2225 { 2226 2227 switch (af) { 2228 case AF_INET: return 4; 2229 #ifdef INET6 2230 case AF_INET6: return 6; 2231 #endif 2232 default: return -1; 2233 } 2234 } 2235 2236 int 2237 epsvproto2af(int proto) 2238 { 2239 2240 switch (proto) { 2241 case 1: return AF_INET; 2242 #ifdef INET6 2243 case 2: return AF_INET6; 2244 #endif 2245 default: return -1; 2246 } 2247 } 2248 2249 int 2250 af2epsvproto(int af) 2251 { 2252 2253 switch (af) { 2254 case AF_INET: return 1; 2255 #ifdef INET6 2256 case AF_INET6: return 2; 2257 #endif 2258 default: return -1; 2259 } 2260 } 2261 2262 /* 2263 * 228 Entering Long Passive Mode (af, hal, h1, h2, h3,..., pal, p1, p2...) 2264 * 229 Entering Extended Passive Mode (|||port|) 2265 */ 2266 void 2267 long_passive(char *cmd, int pf) 2268 { 2269 int len, on; 2270 register u_char *p, *a; 2271 2272 if (!logged_in) { 2273 syslog(LOG_NOTICE, "long passive but not logged in"); 2274 reply(503, "Login with USER first."); 2275 return; 2276 } 2277 2278 if (pf != PF_UNSPEC && ctrl_addr.su_family != pf) { 2279 /* 2280 * XXX 2281 * only EPRT/EPSV ready clients will understand this 2282 */ 2283 if (strcmp(cmd, "EPSV") != 0) 2284 reply(501, "Network protocol mismatch"); /*XXX*/ 2285 else 2286 epsv_protounsupp("Network protocol mismatch"); 2287 2288 return; 2289 } 2290 2291 if (pdata >= 0) 2292 close(pdata); 2293 /* 2294 * XXX 2295 * At this point, it would be nice to have an algorithm that 2296 * inserted a growing delay in an attack scenario. Such a thing 2297 * would look like continual passive sockets being opened, but 2298 * nothing serious being done with them. They not used to move 2299 * data; the entire attempt is just to use tcp FIN_WAIT 2300 * resources. 2301 */ 2302 pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 2303 if (pdata < 0) { 2304 perror_reply(425, "Can't open passive connection"); 2305 return; 2306 } 2307 2308 switch (ctrl_addr.su_family) { 2309 case AF_INET: 2310 #ifdef IP_PORTRANGE 2311 on = high_data_ports ? IP_PORTRANGE_HIGH : IP_PORTRANGE_DEFAULT; 2312 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2313 (char *)&on, sizeof(on)) < 0) 2314 goto pasv_error; 2315 #endif 2316 break; 2317 case AF_INET6: 2318 #ifdef IPV6_PORTRANGE 2319 on = high_data_ports ? IPV6_PORTRANGE_HIGH 2320 : IPV6_PORTRANGE_DEFAULT; 2321 if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE, 2322 (char *)&on, sizeof(on)) < 0) 2323 goto pasv_error; 2324 #endif 2325 break; 2326 } 2327 2328 pasv_addr = ctrl_addr; 2329 pasv_addr.su_port = 0; 2330 (void) seteuid((uid_t) 0); 2331 if (bind(pdata, (struct sockaddr *) &pasv_addr, pasv_addr.su_len) < 0) { 2332 (void) seteuid((uid_t) pw->pw_uid); 2333 goto pasv_error; 2334 } 2335 (void) seteuid((uid_t) pw->pw_uid); 2336 len = pasv_addr.su_len; 2337 if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0) 2338 goto pasv_error; 2339 if (listen(pdata, 1) < 0) 2340 goto pasv_error; 2341 p = (u_char *) &pasv_addr.su_port; 2342 2343 if (strcmp(cmd, "LPSV") == 0) { 2344 switch (pasv_addr.su_family) { 2345 case AF_INET: 2346 a = (u_char *) &pasv_addr.su_sin.sin_addr; 2347 reply(228, 2348 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2349 4, 4, a[0], a[1], a[2], a[3], 2, p[0], p[1]); 2350 return; 2351 case AF_INET6: 2352 a = (char *) &pasv_addr.su_sin6.sin6_addr; 2353 reply(228, 2354 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u," 2355 "%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2356 6, 16, a[0], a[1], a[2], a[3], a[4], 2357 a[5], a[6], a[7], a[8], a[9], a[10], 2358 a[11], a[12], a[13], a[14], a[15], 2359 2, p[0], p[1]); 2360 return; 2361 } 2362 } else if (strcmp(cmd, "EPSV") == 0) { 2363 switch (pasv_addr.su_family) { 2364 case AF_INET: 2365 case AF_INET6: 2366 reply(229, "Entering Extended Passive Mode (|||%u|)", 2367 ntohs(pasv_addr.su_port)); 2368 return; 2369 } 2370 } else { 2371 /* more proper error code? */ 2372 } 2373 2374 pasv_error: 2375 (void) close(pdata); 2376 pdata = -1; 2377 perror_reply(425, "Can't open passive connection"); 2378 return; 2379 } 2380 2381 /* 2382 * EPRT |proto|addr|port| 2383 */ 2384 int 2385 extended_port(const char *arg) 2386 { 2387 char *tmp = NULL; 2388 char *result[3]; 2389 char *p, *q; 2390 char delim; 2391 struct addrinfo hints; 2392 struct addrinfo *res = NULL; 2393 int i; 2394 unsigned long proto; 2395 2396 if (epsvall) { 2397 reply(501, "EPRT disallowed after EPSV ALL"); 2398 return -1; 2399 } 2400 2401 usedefault = 0; 2402 if (pdata >= 0) { 2403 (void) close(pdata); 2404 pdata = -1; 2405 } 2406 2407 tmp = strdup(arg); 2408 if (!tmp) { 2409 fatal("not enough core."); 2410 /*NOTREACHED*/ 2411 } 2412 p = tmp; 2413 delim = p[0]; 2414 p++; 2415 memset(result, 0, sizeof(result)); 2416 for (i = 0; i < 3; i++) { 2417 q = strchr(p, delim); 2418 if (!q || *q != delim) 2419 goto parsefail; 2420 *q++ = '\0'; 2421 result[i] = p; 2422 p = q; 2423 } 2424 2425 /* some more sanity check */ 2426 p = NULL; 2427 (void)strtoul(result[2], &p, 10); 2428 if (!*result[2] || *p) 2429 goto protounsupp; 2430 p = NULL; 2431 proto = strtoul(result[0], &p, 10); 2432 if (!*result[0] || *p) 2433 goto protounsupp; 2434 2435 memset(&hints, 0, sizeof(hints)); 2436 hints.ai_family = epsvproto2af((int)proto); 2437 if (hints.ai_family < 0) 2438 goto protounsupp; 2439 hints.ai_socktype = SOCK_STREAM; 2440 hints.ai_flags = AI_NUMERICHOST; /*no DNS*/ 2441 if (getaddrinfo(result[1], result[2], &hints, &res)) 2442 goto parsefail; 2443 if (res->ai_next) 2444 goto parsefail; 2445 if (sizeof(data_dest) < res->ai_addrlen) 2446 goto parsefail; 2447 memcpy(&data_dest, res->ai_addr, res->ai_addrlen); 2448 if (his_addr.su_family == AF_INET6 && 2449 data_dest.su_family == AF_INET6) { 2450 /* XXX more sanity checks! */ 2451 data_dest.su_sin6.sin6_scope_id = 2452 his_addr.su_sin6.sin6_scope_id; 2453 } 2454 if (pdata >= 0) { 2455 (void) close(pdata); 2456 pdata = -1; 2457 } 2458 reply(200, "EPRT command successful."); 2459 2460 if (tmp) 2461 free(tmp); 2462 if (res) 2463 freeaddrinfo(res); 2464 return 0; 2465 2466 parsefail: 2467 reply(500, "Invalid argument, rejected."); 2468 usedefault = 1; 2469 if (tmp) 2470 free(tmp); 2471 if (res) 2472 freeaddrinfo(res); 2473 return -1; 2474 2475 protounsupp: 2476 epsv_protounsupp("Protocol not supported"); 2477 usedefault = 1; 2478 if (tmp) 2479 free(tmp); 2480 if (res) 2481 freeaddrinfo(res); 2482 return -1; 2483 } 2484 2485 /* 2486 * 522 Protocol not supported (proto,...) 2487 * as we assume address family for control and data connections are the same, 2488 * we do not return the list of address families we support - instead, we 2489 * return the address family of the control connection. 2490 */ 2491 void 2492 epsv_protounsupp(const char *message) 2493 { 2494 int proto; 2495 2496 proto = af2epsvproto(ctrl_addr.su_family); 2497 if (proto < 0) 2498 reply(501, "%s", message); /*XXX*/ 2499 else 2500 reply(522, "%s, use (%d)", message, proto); 2501 } 2502 2503 /* 2504 * Generate unique name for file with basename "local". 2505 * The file named "local" is already known to exist. 2506 * Generates failure reply on error. 2507 */ 2508 static int 2509 guniquefd(local, nam) 2510 char *local; 2511 char **nam; 2512 { 2513 static char new[MAXPATHLEN]; 2514 struct stat st; 2515 int count, len, fd; 2516 char *cp; 2517 2518 cp = strrchr(local, '/'); 2519 if (cp) 2520 *cp = '\0'; 2521 if (stat(cp ? local : ".", &st) < 0) { 2522 perror_reply(553, cp ? local : "."); 2523 return (-1); 2524 } 2525 if (cp) 2526 *cp = '/'; 2527 len = strlcpy(new, local, sizeof(new)); 2528 if (len+2+1 >= sizeof(new)-1) 2529 return (-1); 2530 cp = new + len; 2531 *cp++ = '.'; 2532 for (count = 1; count < 100; count++) { 2533 (void)snprintf(cp, sizeof(new) - (cp - new), "%d", count); 2534 fd = open(new, O_RDWR|O_CREAT|O_EXCL, 0666); 2535 if (fd == -1) 2536 continue; 2537 if (nam) 2538 *nam = new; 2539 return (fd); 2540 } 2541 reply(452, "Unique file name cannot be created."); 2542 return (-1); 2543 } 2544 2545 /* 2546 * Format and send reply containing system error number. 2547 */ 2548 void 2549 perror_reply(code, string) 2550 int code; 2551 char *string; 2552 { 2553 2554 reply(code, "%s: %s.", string, strerror(errno)); 2555 } 2556 2557 static char *onefile[] = { 2558 "", 2559 0 2560 }; 2561 2562 void 2563 send_file_list(whichf) 2564 char *whichf; 2565 { 2566 struct stat st; 2567 DIR *dirp = NULL; 2568 struct dirent *dir; 2569 FILE *dout = NULL; 2570 char **dirlist; 2571 char *dirname; 2572 int simple = 0; 2573 volatile int freeglob = 0; 2574 glob_t gl; 2575 2576 if (strpbrk(whichf, "~{[*?") != NULL) { 2577 memset(&gl, 0, sizeof(gl)); 2578 freeglob = 1; 2579 if (glob(whichf, 2580 GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE|GLOB_LIMIT, 2581 0, &gl)) { 2582 reply(550, "not found"); 2583 goto out; 2584 } else if (gl.gl_pathc == 0) { 2585 errno = ENOENT; 2586 perror_reply(550, whichf); 2587 goto out; 2588 } 2589 dirlist = gl.gl_pathv; 2590 } else { 2591 onefile[0] = whichf; 2592 dirlist = onefile; 2593 simple = 1; 2594 } 2595 2596 if (setjmp(urgcatch)) { 2597 transflag = 0; 2598 goto out; 2599 } 2600 while ((dirname = *dirlist++)) { 2601 if (stat(dirname, &st) < 0) { 2602 /* 2603 * If user typed "ls -l", etc, and the client 2604 * used NLST, do what the user meant. 2605 */ 2606 if (dirname[0] == '-' && *dirlist == NULL && 2607 transflag == 0) { 2608 retrieve("/bin/ls %s", dirname); 2609 goto out; 2610 } 2611 perror_reply(550, whichf); 2612 if (dout != NULL) { 2613 (void) fclose(dout); 2614 transflag = 0; 2615 data = -1; 2616 pdata = -1; 2617 } 2618 goto out; 2619 } 2620 2621 if (S_ISREG(st.st_mode)) { 2622 if (dout == NULL) { 2623 dout = dataconn("file list", (off_t)-1, "w"); 2624 if (dout == NULL) 2625 goto out; 2626 transflag++; 2627 } 2628 fprintf(dout, "%s%s\n", dirname, 2629 type == TYPE_A ? "\r" : ""); 2630 byte_count += strlen(dirname) + 1; 2631 continue; 2632 } else if (!S_ISDIR(st.st_mode)) 2633 continue; 2634 2635 if ((dirp = opendir(dirname)) == NULL) 2636 continue; 2637 2638 while ((dir = readdir(dirp)) != NULL) { 2639 char nbuf[MAXPATHLEN]; 2640 2641 if (dir->d_name[0] == '.' && dir->d_namlen == 1) 2642 continue; 2643 if (dir->d_name[0] == '.' && dir->d_name[1] == '.' && 2644 dir->d_namlen == 2) 2645 continue; 2646 2647 snprintf(nbuf, sizeof(nbuf), "%s/%s", dirname, 2648 dir->d_name); 2649 2650 /* 2651 * We have to do a stat to insure it's 2652 * not a directory or special file. 2653 */ 2654 if (simple || (stat(nbuf, &st) == 0 && 2655 S_ISREG(st.st_mode))) { 2656 if (dout == NULL) { 2657 dout = dataconn("file list", (off_t)-1, 2658 "w"); 2659 if (dout == NULL) 2660 goto out; 2661 transflag++; 2662 } 2663 if (nbuf[0] == '.' && nbuf[1] == '/') 2664 fprintf(dout, "%s%s\n", &nbuf[2], 2665 type == TYPE_A ? "\r" : ""); 2666 else 2667 fprintf(dout, "%s%s\n", nbuf, 2668 type == TYPE_A ? "\r" : ""); 2669 byte_count += strlen(nbuf) + 1; 2670 } 2671 } 2672 (void) closedir(dirp); 2673 } 2674 2675 if (dout == NULL) 2676 reply(550, "No files found."); 2677 else if (ferror(dout) != 0) 2678 perror_reply(550, "Data connection"); 2679 else 2680 reply(226, "Transfer complete."); 2681 2682 transflag = 0; 2683 if (dout != NULL) 2684 (void) fclose(dout); 2685 else { 2686 if (pdata >= 0) 2687 close(pdata); 2688 } 2689 data = -1; 2690 pdata = -1; 2691 out: 2692 if (freeglob) { 2693 freeglob = 0; 2694 globfree(&gl); 2695 } 2696 } 2697 2698 static void 2699 reapchild(signo) 2700 int signo; 2701 { 2702 int save_errno = errno; 2703 2704 while (wait3(NULL, WNOHANG, NULL) > 0) 2705 ; 2706 errno = save_errno; 2707 } 2708 2709 void 2710 logxfer(name, size, start) 2711 char *name; 2712 off_t size; 2713 time_t start; 2714 { 2715 char buf[400 + MAXHOSTNAMELEN*4 + MAXPATHLEN*4]; 2716 char dir[MAXPATHLEN], path[MAXPATHLEN], rpath[MAXPATHLEN]; 2717 char vremotehost[MAXHOSTNAMELEN*4], vpath[MAXPATHLEN*4]; 2718 char *vpw; 2719 time_t now; 2720 int len; 2721 2722 if ((statfd >= 0) && (getcwd(dir, sizeof(dir)) != NULL)) { 2723 time(&now); 2724 2725 vpw = malloc(strlen(guest ? guestpw : pw->pw_name) * 4 + 1); 2726 if (vpw == NULL) 2727 return; 2728 2729 snprintf(path, sizeof(path), "%s/%s", dir, name); 2730 if (realpath(path, rpath) == NULL) 2731 strlcpy(rpath, path, sizeof(rpath)); 2732 strvis(vpath, rpath, VIS_SAFE|VIS_NOSLASH); 2733 2734 strvis(vremotehost, remotehost, VIS_SAFE|VIS_NOSLASH); 2735 strvis(vpw, guest? guestpw : pw->pw_name, VIS_SAFE|VIS_NOSLASH); 2736 2737 len = snprintf(buf, sizeof(buf), 2738 "%.24s %d %s %qd %s %c %s %c %c %s ftp %d %s %s\n", 2739 ctime(&now), now - start + (now == start), 2740 vremotehost, (long long) size, vpath, 2741 ((type == TYPE_A) ? 'a' : 'b'), "*" /* none yet */, 2742 'o', ((guest) ? 'a' : 'r'), 2743 vpw, 0 /* none yet */, 2744 ((guest) ? "*" : pw->pw_name), dhostname); 2745 if (len >= sizeof(buf)) { 2746 len = sizeof(buf); 2747 buf[sizeof(buf) - 1] = '\n'; 2748 } 2749 write(statfd, buf, len); 2750 free(vpw); 2751 } 2752 } 2753 2754 #if defined(TCPWRAPPERS) 2755 static int 2756 check_host(sa) 2757 struct sockaddr *sa; 2758 { 2759 struct sockaddr_in *sin; 2760 struct hostent *hp; 2761 char *addr; 2762 2763 if (sa->sa_family != AF_INET) 2764 return 1; /*XXX*/ 2765 2766 sin = (struct sockaddr_in *)sa; 2767 hp = gethostbyaddr((char *)&sin->sin_addr, 2768 sizeof(struct in_addr), AF_INET); 2769 addr = inet_ntoa(sin->sin_addr); 2770 if (hp) { 2771 if (!hosts_ctl("ftpd", hp->h_name, addr, STRING_UNKNOWN)) { 2772 syslog(LOG_NOTICE, "tcpwrappers rejected: %s [%s]", 2773 hp->h_name, addr); 2774 return (0); 2775 } 2776 } else { 2777 if (!hosts_ctl("ftpd", STRING_UNKNOWN, addr, STRING_UNKNOWN)) { 2778 syslog(LOG_NOTICE, "tcpwrappers rejected: [%s]", addr); 2779 return (0); 2780 } 2781 } 2782 return (1); 2783 } 2784 #endif /* TCPWRAPPERS */ 2785 2786 /* 2787 * Allocate space and return a copy of the specified dir. 2788 * If 'dir' begins with a tilde (~), expand it. 2789 */ 2790 char * 2791 copy_dir(dir, pw) 2792 char *dir; 2793 struct passwd *pw; 2794 { 2795 char *cp; 2796 char *newdir; 2797 char *user = NULL; 2798 size_t dirsiz; 2799 2800 /* Nothing to expand */ 2801 if (dir[0] != '~') 2802 return (strdup(dir)); 2803 2804 /* "dir" is of form ~user/some/dir, lookup user. */ 2805 if (dir[1] != '/' && dir[1] != '\0') { 2806 if ((cp = strchr(dir + 1, '/')) == NULL) 2807 cp = dir + strlen(dir); 2808 if ((user = malloc(cp - dir)) == NULL) 2809 return (NULL); 2810 strlcpy(user, dir + 1, cp - dir); 2811 2812 /* Only do lookup if it is a different user. */ 2813 if (strcmp(user, pw->pw_name) != 0) { 2814 if ((pw = getpwnam(user)) == NULL) { 2815 /* No such user, interpret literally */ 2816 free(user); 2817 return(strdup(dir)); 2818 } 2819 } 2820 } 2821 2822 /* 2823 * If there is no directory separator (/) then it is just pw_dir. 2824 * Otherwise, replace ~foo with pw_dir. 2825 */ 2826 if ((cp = strchr(dir + 1, '/')) == NULL) { 2827 newdir = strdup(pw->pw_dir); 2828 } else { 2829 dirsiz = strlen(cp) + strlen(pw->pw_dir) + 1; 2830 if ((newdir = malloc(dirsiz)) == NULL) 2831 return (NULL); 2832 strcpy(newdir, pw->pw_dir); 2833 strcat(newdir, cp); 2834 } 2835 2836 if (user) 2837 free(user); 2838 return(newdir); 2839 } 2840