1 /* $OpenBSD: ftpd.c,v 1.193 2011/02/09 21:13:31 millert Exp $ */ 2 /* $NetBSD: ftpd.c,v 1.15 1995/06/03 22:46:47 mycroft Exp $ */ 3 4 /* 5 * Copyright (C) 1997 and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. Neither the name of the University nor the names of its contributors 46 * may be used to endorse or promote products derived from this software 47 * without specific prior written permission. 48 * 49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 59 * SUCH DAMAGE. 60 */ 61 62 /* 63 * FTP server. 64 */ 65 #include <sys/param.h> 66 #include <sys/stat.h> 67 #include <sys/ioctl.h> 68 #include <sys/socket.h> 69 #include <sys/wait.h> 70 #include <sys/mman.h> 71 72 #include <netinet/in.h> 73 #include <netinet/in_systm.h> 74 #include <netinet/ip.h> 75 #include <netinet/tcp.h> 76 77 #define FTP_NAMES 78 #include <arpa/ftp.h> 79 #include <arpa/inet.h> 80 #include <arpa/telnet.h> 81 82 #include <bsd_auth.h> 83 #include <ctype.h> 84 #include <dirent.h> 85 #include <errno.h> 86 #include <fcntl.h> 87 #include <glob.h> 88 #include <limits.h> 89 #include <login_cap.h> 90 #include <netdb.h> 91 #include <pwd.h> 92 #include <signal.h> 93 #include <stdarg.h> 94 #include <stdio.h> 95 #include <stdlib.h> 96 #include <string.h> 97 #include <syslog.h> 98 #include <time.h> 99 #include <vis.h> 100 #include <unistd.h> 101 #include <util.h> 102 #include <utmp.h> 103 #include <poll.h> 104 105 #if defined(TCPWRAPPERS) 106 #include <tcpd.h> 107 #endif /* TCPWRAPPERS */ 108 109 #include "pathnames.h" 110 #include "monitor.h" 111 #include "extern.h" 112 113 extern off_t restart_point; 114 extern char cbuf[]; 115 116 union sockunion ctrl_addr; 117 union sockunion data_source; 118 union sockunion data_dest; 119 union sockunion his_addr; 120 union sockunion pasv_addr; 121 122 sigset_t allsigs; 123 124 int daemon_mode = 0; 125 int data; 126 int logged_in; 127 struct passwd *pw; 128 int debug = 0; 129 int timeout = 900; /* timeout after 15 minutes of inactivity */ 130 int maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */ 131 int logging; 132 int anon_ok = 1; 133 int anon_only = 0; 134 int multihome = 0; 135 int guest; 136 int stats; 137 int statfd = -1; 138 int portcheck = 1; 139 int dochroot; 140 int type; 141 int form; 142 int stru; /* avoid C keyword */ 143 int mode; 144 int doutmp = 0; /* update utmp file */ 145 int usedefault = 1; /* for data transfers */ 146 int pdata = -1; /* for passive mode */ 147 int family = AF_UNSPEC; 148 volatile sig_atomic_t transflag; 149 off_t file_size; 150 off_t byte_count; 151 #if !defined(CMASK) || CMASK == 0 152 #undef CMASK 153 #define CMASK 022 154 #endif 155 mode_t defumask = CMASK; /* default umask value */ 156 int umaskchange = 1; /* allow user to change umask value. */ 157 char tmpline[7]; 158 char hostname[MAXHOSTNAMELEN]; 159 char remotehost[MAXHOSTNAMELEN]; 160 char dhostname[MAXHOSTNAMELEN]; 161 char *guestpw; 162 char ttyline[20]; 163 #if 0 164 char *tty = ttyline; /* for klogin */ 165 #endif 166 static struct utmp utmp; /* for utmp */ 167 static login_cap_t *lc; 168 static auth_session_t *as; 169 static volatile sig_atomic_t recvurg; 170 171 #if defined(TCPWRAPPERS) 172 int allow_severity = LOG_INFO; 173 int deny_severity = LOG_NOTICE; 174 #endif /* TCPWRAPPERS */ 175 176 int epsvall = 0; 177 178 /* 179 * Timeout intervals for retrying connections 180 * to hosts that don't accept PORT cmds. This 181 * is a kludge, but given the problems with TCP... 182 */ 183 #define SWAITMAX 90 /* wait at most 90 seconds */ 184 #define SWAITINT 5 /* interval between retries */ 185 186 int swaitmax = SWAITMAX; 187 int swaitint = SWAITINT; 188 189 #ifdef HASSETPROCTITLE 190 char proctitle[BUFSIZ]; /* initial part of title */ 191 #endif /* HASSETPROCTITLE */ 192 193 #define LOGCMD(cmd, file) \ 194 if (logging > 1) \ 195 syslog(LOG_INFO,"%s %s%s", cmd, \ 196 *(file) == '/' ? "" : curdir(), file); 197 #define LOGCMD2(cmd, file1, file2) \ 198 if (logging > 1) \ 199 syslog(LOG_INFO,"%s %s%s %s%s", cmd, \ 200 *(file1) == '/' ? "" : curdir(), file1, \ 201 *(file2) == '/' ? "" : curdir(), file2); 202 #define LOGBYTES(cmd, file, cnt) \ 203 if (logging > 1) { \ 204 if (cnt == (off_t)-1) \ 205 syslog(LOG_INFO,"%s %s%s", cmd, \ 206 *(file) == '/' ? "" : curdir(), file); \ 207 else \ 208 syslog(LOG_INFO, "%s %s%s = %qd bytes", \ 209 cmd, (*(file) == '/') ? "" : curdir(), file, cnt); \ 210 } 211 212 static void ack(char *); 213 static void sigurg(int); 214 static void myoob(void); 215 static int checkuser(char *, char *); 216 static FILE *dataconn(char *, off_t, char *); 217 static void dolog(struct sockaddr *); 218 static char *copy_dir(char *, struct passwd *); 219 static char *curdir(void); 220 static void end_login(void); 221 static FILE *getdatasock(char *); 222 static int guniquefd(char *, char **); 223 static void lostconn(int); 224 static void sigquit(int); 225 static int receive_data(FILE *, FILE *); 226 static void replydirname(const char *, const char *); 227 static int send_data(FILE *, FILE *, off_t, off_t, int); 228 static struct passwd * 229 sgetpwnam(char *, struct passwd *); 230 static void reapchild(int); 231 #if defined(TCPWRAPPERS) 232 static int check_host(struct sockaddr *); 233 #endif /* TCPWRAPPERS */ 234 static void usage(void); 235 236 void logxfer(char *, off_t, time_t); 237 void set_slave_signals(void); 238 239 static char * 240 curdir(void) 241 { 242 static char path[MAXPATHLEN+1]; /* path + '/' */ 243 244 if (getcwd(path, sizeof(path)-1) == NULL) 245 return (""); 246 if (path[1] != '\0') /* special case for root dir. */ 247 strlcat(path, "/", sizeof path); 248 /* For guest account, skip / since it's chrooted */ 249 return (guest ? path+1 : path); 250 } 251 252 char *argstr = "AdDhnlMSt:T:u:UvP46"; 253 254 static void 255 usage(void) 256 { 257 syslog(LOG_ERR, 258 "usage: ftpd [-46ADdlMnPSU] [-T maxtimeout] [-t timeout] [-u mask]"); 259 exit(2); 260 } 261 262 int 263 main(int argc, char *argv[]) 264 { 265 socklen_t addrlen; 266 int ch, on = 1, tos; 267 char line[LINE_MAX]; 268 FILE *fp; 269 struct hostent *hp; 270 struct sigaction sa; 271 int error = 0; 272 const char *errstr; 273 274 tzset(); /* in case no timezone database in ~ftp */ 275 sigfillset(&allsigs); /* used to block signals while root */ 276 sigemptyset(&sa.sa_mask); 277 sa.sa_flags = SA_RESTART; 278 279 while ((ch = getopt(argc, argv, argstr)) != -1) { 280 switch (ch) { 281 case 'A': 282 anon_only = 1; 283 break; 284 285 case 'd': 286 case 'v': /* deprecated */ 287 debug = 1; 288 break; 289 290 case 'D': 291 daemon_mode = 1; 292 break; 293 294 case 'P': 295 portcheck = 0; 296 break; 297 298 case 'h': /* deprecated */ 299 break; 300 301 case 'l': 302 logging++; /* > 1 == extra logging */ 303 break; 304 305 case 'M': 306 multihome = 1; 307 break; 308 309 case 'n': 310 anon_ok = 0; 311 break; 312 313 case 'S': 314 stats = 1; 315 break; 316 317 case 't': 318 timeout = strtonum(optarg, 0, INT_MAX, &errstr); 319 if (errstr) { 320 syslog(LOG_ERR, 321 "%s is a bad value for -t, aborting", 322 optarg); 323 exit(2); 324 } 325 if (maxtimeout < timeout) 326 maxtimeout = timeout; 327 break; 328 329 case 'T': 330 maxtimeout = strtonum(optarg, 0, INT_MAX, 331 &errstr); 332 if (errstr) { 333 syslog(LOG_ERR, 334 "%s is a bad value for -T, aborting", 335 optarg); 336 exit(2); 337 } 338 if (timeout > maxtimeout) 339 timeout = maxtimeout; 340 break; 341 342 case 'u': 343 { 344 long val = 0; 345 char *p; 346 umaskchange = 0; 347 348 val = strtol(optarg, &p, 8); 349 if (*optarg == '\0' || *p != '\0' || val < 0 || 350 (val & ~ACCESSPERMS)) { 351 syslog(LOG_ERR, 352 "%s is a bad value for -u, aborting", 353 optarg); 354 exit(2); 355 } 356 defumask = val; 357 break; 358 } 359 360 case 'U': 361 doutmp = 1; 362 break; 363 364 case '4': 365 family = AF_INET; 366 break; 367 368 case '6': 369 family = AF_INET6; 370 break; 371 372 default: 373 usage(); 374 break; 375 } 376 } 377 378 (void) freopen(_PATH_DEVNULL, "w", stderr); 379 380 /* 381 * LOG_NDELAY sets up the logging connection immediately, 382 * necessary for anonymous ftp's that chroot and can't do it later. 383 */ 384 openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP); 385 386 if (getpwnam(FTPD_PRIVSEP_USER) == NULL) { 387 syslog(LOG_ERR, "privilege separation user %s not found", 388 FTPD_PRIVSEP_USER); 389 exit(1); 390 } 391 endpwent(); 392 393 if (daemon_mode) { 394 int *fds, i, fd; 395 struct pollfd *pfds; 396 struct addrinfo hints, *res, *res0; 397 nfds_t n; 398 399 /* 400 * Detach from parent. 401 */ 402 if (daemon(1, 1) < 0) { 403 syslog(LOG_ERR, "failed to become a daemon"); 404 exit(1); 405 } 406 sa.sa_handler = reapchild; 407 (void) sigaction(SIGCHLD, &sa, NULL); 408 409 memset(&hints, 0, sizeof(hints)); 410 hints.ai_family = family; 411 hints.ai_socktype = SOCK_STREAM; 412 hints.ai_protocol = IPPROTO_TCP; 413 hints.ai_flags = AI_PASSIVE; 414 error = getaddrinfo(NULL, "ftp", &hints, &res0); 415 if (error) { 416 syslog(LOG_ERR, "%s", gai_strerror(error)); 417 exit(1); 418 } 419 420 n = 0; 421 for (res = res0; res; res = res->ai_next) 422 n++; 423 424 fds = calloc(n, sizeof(int)); 425 pfds = calloc(n, sizeof(struct pollfd)); 426 if (!fds || !pfds) { 427 syslog(LOG_ERR, "%s", strerror(errno)); 428 exit(1); 429 } 430 431 /* 432 * Open sockets, bind it to the FTP port, and start 433 * listening. 434 */ 435 n = 0; 436 for (res = res0; res; res = res->ai_next) { 437 fds[n] = socket(res->ai_family, res->ai_socktype, 438 res->ai_protocol); 439 if (fds[n] < 0) 440 continue; 441 442 if (setsockopt(fds[n], SOL_SOCKET, SO_KEEPALIVE, 443 &on, sizeof(on)) < 0) { 444 close(fds[n]); 445 fds[n] = -1; 446 continue; 447 } 448 449 if (setsockopt(fds[n], SOL_SOCKET, SO_REUSEADDR, 450 &on, sizeof(on)) < 0) { 451 close(fds[n]); 452 fds[n] = -1; 453 continue; 454 } 455 456 if (bind(fds[n], res->ai_addr, res->ai_addrlen) < 0) { 457 close(fds[n]); 458 fds[n] = -1; 459 continue; 460 } 461 if (listen(fds[n], 32) < 0) { 462 close(fds[n]); 463 fds[n] = -1; 464 continue; 465 } 466 467 pfds[n].fd = fds[n]; 468 pfds[n].events = POLLIN; 469 n++; 470 } 471 freeaddrinfo(res0); 472 473 if (n == 0) { 474 syslog(LOG_ERR, "could not open control socket"); 475 exit(1); 476 } 477 478 /* Stash pid in pidfile */ 479 if (pidfile(NULL)) 480 syslog(LOG_ERR, "can't open pidfile: %m"); 481 /* 482 * Loop forever accepting connection requests and forking off 483 * children to handle them. 484 */ 485 while (1) { 486 if (poll(pfds, n, INFTIM) < 0) { 487 if (errno == EINTR) 488 continue; 489 syslog(LOG_ERR, "poll: %m"); 490 exit(1); 491 } 492 for (i = 0; i < n; i++) 493 if (pfds[i].revents & POLLIN) { 494 addrlen = sizeof(his_addr); 495 fd = accept(pfds[i].fd, 496 (struct sockaddr *)&his_addr, 497 &addrlen); 498 if (fd != -1) { 499 if (fork() == 0) 500 goto child; 501 close(fd); 502 } 503 } 504 } 505 506 child: 507 /* child */ 508 (void)dup2(fd, STDIN_FILENO); 509 (void)dup2(fd, STDOUT_FILENO); 510 for (i = 0; i < n; i++) 511 close(fds[i]); 512 #if defined(TCPWRAPPERS) 513 /* ..in the child. */ 514 if (!check_host((struct sockaddr *)&his_addr)) 515 exit(1); 516 #endif /* TCPWRAPPERS */ 517 } else { 518 addrlen = sizeof(his_addr); 519 if (getpeername(0, (struct sockaddr *)&his_addr, 520 &addrlen) < 0) { 521 /* syslog(LOG_ERR, "getpeername (%s): %m", argv[0]); */ 522 exit(1); 523 } 524 } 525 526 /* set this here so klogin can use it... */ 527 (void)snprintf(ttyline, sizeof(ttyline), "ftp%ld", (long)getpid()); 528 529 set_slave_signals(); 530 531 addrlen = sizeof(ctrl_addr); 532 if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) { 533 syslog(LOG_ERR, "getsockname: %m"); 534 exit(1); 535 } 536 if (his_addr.su_family == AF_INET6 && 537 IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr)) { 538 #if 1 539 /* 540 * IPv4 control connection arrived to AF_INET6 socket. 541 * I hate to do this, but this is the easiest solution. 542 */ 543 union sockunion tmp_addr; 544 const int off = sizeof(struct in6_addr) - sizeof(struct in_addr); 545 546 tmp_addr = his_addr; 547 memset(&his_addr, 0, sizeof(his_addr)); 548 his_addr.su_sin.sin_family = AF_INET; 549 his_addr.su_sin.sin_len = sizeof(his_addr.su_sin); 550 memcpy(&his_addr.su_sin.sin_addr, 551 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 552 sizeof(his_addr.su_sin.sin_addr)); 553 his_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 554 555 tmp_addr = ctrl_addr; 556 memset(&ctrl_addr, 0, sizeof(ctrl_addr)); 557 ctrl_addr.su_sin.sin_family = AF_INET; 558 ctrl_addr.su_sin.sin_len = sizeof(ctrl_addr.su_sin); 559 memcpy(&ctrl_addr.su_sin.sin_addr, 560 &tmp_addr.su_sin6.sin6_addr.s6_addr[off], 561 sizeof(ctrl_addr.su_sin.sin_addr)); 562 ctrl_addr.su_sin.sin_port = tmp_addr.su_sin6.sin6_port; 563 #else 564 while (fgets(line, sizeof(line), fd) != NULL) { 565 line[strcspn(line, "\n")] = '\0'; 566 lreply(530, "%s", line); 567 } 568 (void) fflush(stdout); 569 (void) close(fd); 570 reply(530, 571 "Connection from IPv4 mapped address is not supported."); 572 exit(0); 573 #endif 574 } 575 #ifdef IP_TOS 576 if (his_addr.su_family == AF_INET) { 577 tos = IPTOS_LOWDELAY; 578 if (setsockopt(0, IPPROTO_IP, IP_TOS, &tos, 579 sizeof(int)) < 0) 580 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 581 } 582 #endif 583 data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1); 584 585 /* Try to handle urgent data inline */ 586 #ifdef SO_OOBINLINE 587 if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, &on, sizeof(on)) < 0) 588 syslog(LOG_ERR, "setsockopt: %m"); 589 #endif 590 591 dolog((struct sockaddr *)&his_addr); 592 593 /* 594 * Set up default state 595 */ 596 data = -1; 597 type = TYPE_A; 598 form = FORM_N; 599 stru = STRU_F; 600 mode = MODE_S; 601 tmpline[0] = '\0'; 602 603 /* If logins are disabled, print out the message. */ 604 if ((fp = fopen(_PATH_NOLOGIN, "r")) != NULL) { 605 while (fgets(line, sizeof(line), fp) != NULL) { 606 line[strcspn(line, "\n")] = '\0'; 607 lreply(530, "%s", line); 608 } 609 (void) fflush(stdout); 610 (void) fclose(fp); 611 reply(530, "System not available."); 612 exit(0); 613 } 614 if ((fp = fopen(_PATH_FTPWELCOME, "r")) != NULL) { 615 while (fgets(line, sizeof(line), fp) != NULL) { 616 line[strcspn(line, "\n")] = '\0'; 617 lreply(220, "%s", line); 618 } 619 (void) fflush(stdout); 620 (void) fclose(fp); 621 /* reply(220,) must follow */ 622 } 623 (void) gethostname(hostname, sizeof(hostname)); 624 625 /* Make sure hostname is fully qualified. */ 626 hp = gethostbyname(hostname); 627 if (hp != NULL) 628 strlcpy(hostname, hp->h_name, sizeof(hostname)); 629 630 if (multihome) { 631 error = getnameinfo((struct sockaddr *)&ctrl_addr, 632 ctrl_addr.su_len, dhostname, sizeof(dhostname), NULL, 0, 0); 633 } 634 635 if (error != 0) 636 reply(220, "FTP server ready."); 637 else 638 reply(220, "%s FTP server ready.", 639 (multihome ? dhostname : hostname)); 640 641 monitor_init(); 642 643 for (;;) 644 (void) yyparse(); 645 /* NOTREACHED */ 646 } 647 648 /* 649 * Signal handlers. 650 */ 651 /*ARGSUSED*/ 652 static void 653 lostconn(int signo) 654 { 655 struct syslog_data sdata = SYSLOG_DATA_INIT; 656 657 sdata.log_fac = LOG_FTP; 658 if (debug) 659 syslog_r(LOG_DEBUG, &sdata, "lost connection"); 660 dologout(1); 661 } 662 663 static void 664 sigquit(int signo) 665 { 666 struct syslog_data sdata = SYSLOG_DATA_INIT; 667 668 sdata.log_fac = LOG_FTP; 669 syslog_r(LOG_DEBUG, &sdata, "got signal %s", sys_signame[signo]); 670 dologout(1); 671 } 672 673 /* 674 * Save the result of a getpwnam. Used for USER command, since 675 * the data returned must not be clobbered by any other command 676 * (e.g., globbing). 677 */ 678 static struct passwd * 679 sgetpwnam(char *name, struct passwd *pw) 680 { 681 static struct passwd *save; 682 struct passwd *old; 683 684 if (pw == NULL && (pw = getpwnam(name)) == NULL) 685 return (NULL); 686 old = save; 687 save = pw_dup(pw); 688 if (save == NULL) { 689 perror_reply(421, "Local resource failure: malloc"); 690 dologout(1); 691 /* NOTREACHED */ 692 } 693 if (old) { 694 memset(old->pw_passwd, 0, strlen(old->pw_passwd)); 695 free(old); 696 } 697 return (save); 698 } 699 700 static int login_attempts; /* number of failed login attempts */ 701 static int askpasswd; /* had user command, ask for passwd */ 702 static char curname[MAXLOGNAME]; /* current USER name */ 703 704 /* 705 * USER command. 706 * Sets global passwd pointer pw if named account exists and is acceptable; 707 * sets askpasswd if a PASS command is expected. If logged in previously, 708 * need to reset state. If name is "ftp" or "anonymous", the name is not in 709 * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return. 710 * If account doesn't exist, ask for passwd anyway. Otherwise, check user 711 * requesting login privileges. Disallow anyone who does not have a standard 712 * shell as returned by getusershell(). Disallow anyone mentioned in the file 713 * _PATH_FTPUSERS to allow people such as root and uucp to be avoided. 714 */ 715 void 716 user(char *name) 717 { 718 char *cp, *shell, *style, *host; 719 char *class = NULL; 720 721 if (logged_in) { 722 kill_slave("user already logged in"); 723 end_login(); 724 } 725 726 /* Close session from previous user if there was one. */ 727 if (as) { 728 auth_close(as); 729 as = NULL; 730 } 731 if (lc) { 732 login_close(lc); 733 lc = NULL; 734 } 735 736 if ((style = strchr(name, ':')) != NULL) 737 *style++ = 0; 738 739 guest = 0; 740 askpasswd = 0; 741 host = multihome ? dhostname : hostname; 742 if (anon_ok && 743 (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0)) { 744 if (checkuser(_PATH_FTPUSERS, "ftp") || 745 checkuser(_PATH_FTPUSERS, "anonymous")) 746 reply(530, "User %s access denied.", name); 747 else if ((pw = sgetpwnam("ftp", NULL)) != NULL) { 748 if ((lc = login_getclass(pw->pw_class)) == NULL || 749 (as = auth_open()) == NULL || 750 auth_setpwd(as, pw) != 0 || 751 auth_setoption(as, "FTPD_HOST", host) < 0) { 752 if (as) { 753 auth_close(as); 754 as = NULL; 755 } 756 if (lc) { 757 login_close(lc); 758 lc = NULL; 759 } 760 reply(421, "Local resource failure"); 761 return; 762 } 763 guest = 1; 764 askpasswd = 1; 765 reply(331, 766 "Guest login ok, send your email address as password."); 767 } else 768 reply(530, "User %s unknown.", name); 769 if (!askpasswd && logging) 770 syslog(LOG_NOTICE, 771 "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost); 772 return; 773 } 774 775 shell = _PATH_BSHELL; 776 if ((pw = sgetpwnam(name, NULL))) { 777 class = pw->pw_class; 778 if (pw->pw_shell != NULL && *pw->pw_shell != '\0') 779 shell = pw->pw_shell; 780 while ((cp = getusershell()) != NULL) 781 if (strcmp(cp, shell) == 0) 782 break; 783 shell = cp; 784 endusershell(); 785 } 786 787 /* Get login class; if invalid style treat like unknown user. */ 788 lc = login_getclass(class); 789 if (lc && (style = login_getstyle(lc, style, "auth-ftp")) == NULL) { 790 login_close(lc); 791 lc = NULL; 792 pw = NULL; 793 } 794 795 /* Do pre-authentication setup. */ 796 if (lc && ((as = auth_open()) == NULL || 797 (pw != NULL && auth_setpwd(as, pw) != 0) || 798 auth_setitem(as, AUTHV_STYLE, style) < 0 || 799 auth_setitem(as, AUTHV_NAME, name) < 0 || 800 auth_setitem(as, AUTHV_CLASS, class) < 0 || 801 auth_setoption(as, "login", "yes") < 0 || 802 auth_setoption(as, "notickets", "yes") < 0 || 803 auth_setoption(as, "FTPD_HOST", host) < 0)) { 804 if (as) { 805 auth_close(as); 806 as = NULL; 807 } 808 login_close(lc); 809 lc = NULL; 810 reply(421, "Local resource failure"); 811 return; 812 } 813 if (logging) 814 strlcpy(curname, name, sizeof(curname)); 815 816 dochroot = (lc && login_getcapbool(lc, "ftp-chroot", 0)) || 817 checkuser(_PATH_FTPCHROOT, name); 818 if (anon_only && !dochroot) { 819 reply(530, "User %s access denied.", name); 820 return; 821 } 822 if (pw) { 823 if ((!shell && !dochroot) || checkuser(_PATH_FTPUSERS, name)) { 824 reply(530, "User %s access denied.", name); 825 if (logging) 826 syslog(LOG_NOTICE, 827 "FTP LOGIN REFUSED FROM %s, %s", 828 remotehost, name); 829 pw = NULL; 830 return; 831 } 832 } 833 834 if (as != NULL && (cp = auth_challenge(as)) != NULL) 835 reply(331, "%s", cp); 836 else 837 reply(331, "Password required for %s.", name); 838 839 askpasswd = 1; 840 /* 841 * Delay before reading passwd after first failed 842 * attempt to slow down passwd-guessing programs. 843 */ 844 if (login_attempts) 845 sleep((unsigned) login_attempts); 846 } 847 848 /* 849 * Check if a user is in the file "fname" 850 */ 851 static int 852 checkuser(char *fname, char *name) 853 { 854 FILE *fp; 855 int found = 0; 856 char *p, line[BUFSIZ]; 857 858 if ((fp = fopen(fname, "r")) != NULL) { 859 while (fgets(line, sizeof(line), fp) != NULL) 860 if ((p = strchr(line, '\n')) != NULL) { 861 *p = '\0'; 862 if (line[0] == '#') 863 continue; 864 if (strcmp(line, name) == 0) { 865 found = 1; 866 break; 867 } 868 } 869 (void) fclose(fp); 870 } 871 return (found); 872 } 873 874 /* 875 * Terminate login as previous user, if any, resetting state; 876 * used when USER command is given or login fails. 877 */ 878 static void 879 end_login(void) 880 { 881 sigprocmask (SIG_BLOCK, &allsigs, NULL); 882 if (logged_in) { 883 ftpdlogwtmp(ttyline, "", ""); 884 if (doutmp) 885 ftpd_logout(utmp.ut_line); 886 } 887 reply(530, "Please reconnect to work as another user"); 888 _exit(0); 889 } 890 891 enum auth_ret 892 pass(char *passwd) 893 { 894 int authok; 895 unsigned int flags; 896 FILE *fp; 897 static char homedir[MAXPATHLEN]; 898 char *motd, *dir, rootdir[MAXPATHLEN]; 899 size_t sz_pw_dir; 900 901 if (logged_in || askpasswd == 0) { 902 reply(503, "Login with USER first."); 903 return (AUTH_FAILED); 904 } 905 askpasswd = 0; 906 if (!guest) { /* "ftp" is only account allowed no password */ 907 authok = 0; 908 if (pw == NULL || pw->pw_passwd[0] == '\0') { 909 useconds_t us; 910 911 /* Sleep between 1 and 3 seconds to emulate a crypt. */ 912 us = arc4random_uniform(3000000); 913 usleep(us); 914 if (as != NULL) { 915 auth_close(as); 916 as = NULL; 917 } 918 } else { 919 authok = auth_userresponse(as, passwd, 0); 920 as = NULL; 921 } 922 if (authok == 0) { 923 reply(530, "Login incorrect."); 924 if (logging) 925 syslog(LOG_NOTICE, 926 "FTP LOGIN FAILED FROM %s, %s", 927 remotehost, curname); 928 pw = NULL; 929 if (login_attempts++ >= 5) { 930 syslog(LOG_NOTICE, 931 "repeated login failures from %s", 932 remotehost); 933 kill_slave("repeated login failures"); 934 _exit(0); 935 } 936 return (AUTH_FAILED); 937 } 938 } else if (lc != NULL) { 939 /* Save anonymous' password. */ 940 if (guestpw != NULL) 941 free(guestpw); 942 guestpw = strdup(passwd); 943 if (guestpw == NULL) { 944 kill_slave("out of mem"); 945 fatal("Out of memory."); 946 } 947 948 authok = auth_approval(as, lc, pw->pw_name, "ftp"); 949 auth_close(as); 950 as = NULL; 951 if (authok == 0) { 952 syslog(LOG_INFO|LOG_AUTH, 953 "FTP LOGIN FAILED (HOST) as %s: approval failure.", 954 pw->pw_name); 955 reply(530, "Approval failure."); 956 kill_slave("approval failure"); 957 _exit(0); 958 } 959 } else { 960 syslog(LOG_INFO|LOG_AUTH, 961 "FTP LOGIN CLASS %s MISSING for %s: approval failure.", 962 pw->pw_class, pw->pw_name); 963 reply(530, "Permission denied."); 964 kill_slave("permission denied"); 965 _exit(0); 966 } 967 968 if (monitor_post_auth() == 1) { 969 /* Post-auth monitor process */ 970 logged_in = 1; 971 return (AUTH_MONITOR); 972 } 973 974 login_attempts = 0; /* this time successful */ 975 /* set umask via setusercontext() unless -u flag was given. */ 976 flags = LOGIN_SETGROUP|LOGIN_SETPRIORITY|LOGIN_SETRESOURCES; 977 if (umaskchange) 978 flags |= LOGIN_SETUMASK; 979 else 980 (void) umask(defumask); 981 if (setusercontext(lc, pw, (uid_t)0, flags) != 0) { 982 perror_reply(421, "Local resource failure: setusercontext"); 983 syslog(LOG_NOTICE, "setusercontext: %m"); 984 dologout(1); 985 /* NOTREACHED */ 986 } 987 988 /* open wtmp before chroot */ 989 ftpdlogwtmp(ttyline, pw->pw_name, remotehost); 990 991 /* open utmp before chroot */ 992 if (doutmp) { 993 memset((void *)&utmp, 0, sizeof(utmp)); 994 (void)time(&utmp.ut_time); 995 (void)strncpy(utmp.ut_name, pw->pw_name, sizeof(utmp.ut_name)); 996 (void)strncpy(utmp.ut_host, remotehost, sizeof(utmp.ut_host)); 997 (void)strncpy(utmp.ut_line, ttyline, sizeof(utmp.ut_line)); 998 ftpd_login(&utmp); 999 } 1000 1001 /* open stats file before chroot */ 1002 if (guest && (stats == 1) && (statfd < 0)) 1003 if ((statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND)) < 0) 1004 stats = 0; 1005 1006 logged_in = 1; 1007 1008 if ((dir = login_getcapstr(lc, "ftp-dir", NULL, NULL))) { 1009 char *newdir; 1010 1011 newdir = copy_dir(dir, pw); 1012 if (newdir == NULL) { 1013 perror_reply(421, "Local resource failure: malloc"); 1014 dologout(1); 1015 /* NOTREACHED */ 1016 } 1017 pw->pw_dir = newdir; 1018 pw = sgetpwnam(NULL, pw); 1019 free(dir); 1020 free(newdir); 1021 } 1022 1023 /* make sure pw->pw_dir is big enough to hold "/" */ 1024 sz_pw_dir = strlen(pw->pw_dir) + 1; 1025 if (sz_pw_dir < 2) { 1026 pw->pw_dir = "/"; 1027 pw = sgetpwnam(NULL, pw); 1028 sz_pw_dir = 2; 1029 } 1030 1031 if (guest || dochroot) { 1032 if (multihome && guest) { 1033 struct stat ts; 1034 1035 /* Compute root directory. */ 1036 snprintf(rootdir, sizeof(rootdir), "%s/%s", 1037 pw->pw_dir, dhostname); 1038 if (stat(rootdir, &ts) < 0) { 1039 snprintf(rootdir, sizeof(rootdir), "%s/%s", 1040 pw->pw_dir, hostname); 1041 } 1042 } else 1043 strlcpy(rootdir, pw->pw_dir, sizeof(rootdir)); 1044 } 1045 if (guest) { 1046 /* 1047 * We MUST do a chdir() after the chroot. Otherwise 1048 * the old current directory will be accessible as "." 1049 * outside the new root! 1050 */ 1051 if (chroot(rootdir) < 0 || chdir("/") < 0) { 1052 reply(550, "Can't set guest privileges."); 1053 goto bad; 1054 } 1055 strlcpy(pw->pw_dir, "/", sz_pw_dir); 1056 if (setenv("HOME", "/", 1) == -1) { 1057 reply(550, "Can't setup environment."); 1058 goto bad; 1059 } 1060 } else if (dochroot) { 1061 if (chroot(rootdir) < 0 || chdir("/") < 0) { 1062 reply(550, "Can't change root."); 1063 goto bad; 1064 } 1065 strlcpy(pw->pw_dir, "/", sz_pw_dir); 1066 if (setenv("HOME", "/", 1) == -1) { 1067 reply(550, "Can't setup environment."); 1068 goto bad; 1069 } 1070 } else if (chdir(pw->pw_dir) < 0) { 1071 if (chdir("/") < 0) { 1072 reply(530, "User %s: can't change directory to %s.", 1073 pw->pw_name, pw->pw_dir); 1074 goto bad; 1075 } else 1076 lreply(230, "No directory! Logging in with home=/"); 1077 } 1078 if (setegid(pw->pw_gid) < 0 || setgid(pw->pw_gid) < 0) { 1079 reply(550, "Can't set gid."); 1080 goto bad; 1081 } 1082 if (seteuid(pw->pw_uid) < 0 || setuid(pw->pw_uid) < 0) { 1083 reply(550, "Can't set uid."); 1084 goto bad; 1085 } 1086 sigprocmask(SIG_UNBLOCK, &allsigs, NULL); 1087 1088 /* 1089 * Set home directory so that use of ~ (tilde) works correctly. 1090 */ 1091 if (getcwd(homedir, MAXPATHLEN) != NULL) { 1092 if (setenv("HOME", homedir, 1) == -1) { 1093 reply(550, "Can't setup environment."); 1094 goto bad; 1095 } 1096 } 1097 1098 /* 1099 * Display a login message, if it exists. 1100 * N.B. reply(230,) must follow the message. 1101 */ 1102 motd = login_getcapstr(lc, "welcome", NULL, NULL); 1103 if ((fp = fopen(motd ? motd : _PATH_FTPLOGINMESG, "r")) != NULL) { 1104 char line[LINE_MAX]; 1105 1106 while (fgets(line, sizeof(line), fp) != NULL) { 1107 line[strcspn(line, "\n")] = '\0'; 1108 lreply(230, "%s", line); 1109 } 1110 (void) fflush(stdout); 1111 (void) fclose(fp); 1112 } 1113 if (motd != NULL) 1114 free(motd); 1115 if (guest) { 1116 reply(230, "Guest login ok, access restrictions apply."); 1117 #ifdef HASSETPROCTITLE 1118 snprintf(proctitle, sizeof(proctitle), 1119 "%s: anonymous/%.*s", remotehost, 1120 (int)(sizeof(proctitle) - sizeof(remotehost) - 1121 sizeof(": anonymous/")), passwd); 1122 setproctitle("%s", proctitle); 1123 #endif /* HASSETPROCTITLE */ 1124 if (logging) 1125 syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s", 1126 remotehost, passwd); 1127 } else { 1128 reply(230, "User %s logged in.", pw->pw_name); 1129 #ifdef HASSETPROCTITLE 1130 snprintf(proctitle, sizeof(proctitle), 1131 "%s: %s", remotehost, pw->pw_name); 1132 setproctitle("%s", proctitle); 1133 #endif /* HASSETPROCTITLE */ 1134 if (logging) 1135 syslog(LOG_INFO, "FTP LOGIN FROM %s as %s", 1136 remotehost, pw->pw_name); 1137 } 1138 login_close(lc); 1139 lc = NULL; 1140 return (AUTH_SLAVE); 1141 bad: 1142 /* Forget all about it... */ 1143 login_close(lc); 1144 lc = NULL; 1145 end_login(); 1146 return (AUTH_FAILED); 1147 } 1148 1149 void 1150 retrieve(char *cmd, char *name) 1151 { 1152 FILE *fin, *dout; 1153 struct stat st; 1154 int (*closefunc)(FILE *); 1155 time_t start; 1156 1157 if (cmd == 0) { 1158 fin = fopen(name, "r"), closefunc = fclose; 1159 st.st_size = 0; 1160 } else { 1161 char line[BUFSIZ]; 1162 1163 (void) snprintf(line, sizeof(line), cmd, name); 1164 name = line; 1165 fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose; 1166 st.st_size = -1; 1167 st.st_blksize = BUFSIZ; 1168 } 1169 if (fin == NULL) { 1170 if (errno != 0) { 1171 perror_reply(550, name); 1172 if (cmd == 0) { 1173 LOGCMD("get", name); 1174 } 1175 } 1176 return; 1177 } 1178 byte_count = -1; 1179 if (cmd == 0 && (fstat(fileno(fin), &st) < 0 || !S_ISREG(st.st_mode))) { 1180 reply(550, "%s: not a plain file.", name); 1181 goto done; 1182 } 1183 if (restart_point) { 1184 if (type == TYPE_A) { 1185 off_t i, n; 1186 int c; 1187 1188 n = restart_point; 1189 i = 0; 1190 while (i++ < n) { 1191 if ((c = getc(fin)) == EOF) { 1192 if (ferror(fin)) { 1193 perror_reply(550, name); 1194 goto done; 1195 } else 1196 break; 1197 } 1198 if (c == '\n') 1199 i++; 1200 } 1201 } else if (lseek(fileno(fin), restart_point, SEEK_SET) < 0) { 1202 perror_reply(550, name); 1203 goto done; 1204 } 1205 } 1206 dout = dataconn(name, st.st_size, "w"); 1207 if (dout == NULL) 1208 goto done; 1209 time(&start); 1210 send_data(fin, dout, (off_t)st.st_blksize, st.st_size, 1211 (restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode))); 1212 if ((cmd == 0) && stats) 1213 logxfer(name, byte_count, start); 1214 (void) fclose(dout); 1215 data = -1; 1216 done: 1217 if (pdata >= 0) 1218 (void) close(pdata); 1219 pdata = -1; 1220 if (cmd == 0) 1221 LOGBYTES("get", name, byte_count); 1222 (*closefunc)(fin); 1223 } 1224 1225 void 1226 store(char *name, char *mode, int unique) 1227 { 1228 FILE *fout, *din; 1229 int (*closefunc)(FILE *); 1230 struct stat st; 1231 int fd; 1232 1233 if (restart_point && *mode != 'a') 1234 mode = "r+"; 1235 1236 if (unique && stat(name, &st) == 0) { 1237 char *nam; 1238 1239 fd = guniquefd(name, &nam); 1240 if (fd == -1) { 1241 LOGCMD(*mode == 'w' ? "put" : "append", name); 1242 return; 1243 } 1244 name = nam; 1245 fout = fdopen(fd, mode); 1246 } else 1247 fout = fopen(name, mode); 1248 1249 closefunc = fclose; 1250 if (fout == NULL) { 1251 perror_reply(553, name); 1252 LOGCMD(*mode == 'w' ? "put" : "append", name); 1253 return; 1254 } 1255 byte_count = -1; 1256 if (restart_point) { 1257 if (type == TYPE_A) { 1258 off_t i, n; 1259 int c; 1260 1261 n = restart_point; 1262 i = 0; 1263 while (i++ < n) { 1264 if ((c = getc(fout)) == EOF) { 1265 if (ferror(fout)) { 1266 perror_reply(550, name); 1267 goto done; 1268 } else 1269 break; 1270 } 1271 if (c == '\n') 1272 i++; 1273 } 1274 /* 1275 * We must do this seek to "current" position 1276 * because we are changing from reading to 1277 * writing. 1278 */ 1279 if (fseek(fout, 0L, SEEK_CUR) < 0) { 1280 perror_reply(550, name); 1281 goto done; 1282 } 1283 } else if (lseek(fileno(fout), restart_point, SEEK_SET) < 0) { 1284 perror_reply(550, name); 1285 goto done; 1286 } 1287 } 1288 din = dataconn(name, (off_t)-1, "r"); 1289 if (din == NULL) 1290 goto done; 1291 if (receive_data(din, fout) == 0) { 1292 if (unique) 1293 reply(226, "Transfer complete (unique file name:%s).", 1294 name); 1295 else 1296 reply(226, "Transfer complete."); 1297 } 1298 (void) fclose(din); 1299 data = -1; 1300 pdata = -1; 1301 done: 1302 LOGBYTES(*mode == 'w' ? "put" : "append", name, byte_count); 1303 (*closefunc)(fout); 1304 } 1305 1306 static FILE * 1307 getdatasock(char *mode) 1308 { 1309 int on = 1, s, t, tries; 1310 1311 if (data >= 0) 1312 return (fdopen(data, mode)); 1313 sigprocmask (SIG_BLOCK, &allsigs, NULL); 1314 s = monitor_socket(ctrl_addr.su_family); 1315 if (s < 0) 1316 goto bad; 1317 if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, 1318 &on, sizeof(on)) < 0) 1319 goto bad; 1320 /* anchor socket to avoid multi-homing problems */ 1321 data_source = ctrl_addr; 1322 data_source.su_port = htons(20); /* ftp-data port */ 1323 for (tries = 1; ; tries++) { 1324 if (monitor_bind(s, (struct sockaddr *)&data_source, 1325 data_source.su_len) >= 0) 1326 break; 1327 if (errno != EADDRINUSE || tries > 10) 1328 goto bad; 1329 sleep((unsigned int)tries); 1330 } 1331 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1332 1333 #ifdef IP_TOS 1334 if (ctrl_addr.su_family == AF_INET) { 1335 on = IPTOS_THROUGHPUT; 1336 if (setsockopt(s, IPPROTO_IP, IP_TOS, &on, 1337 sizeof(int)) < 0) 1338 syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); 1339 } 1340 #endif 1341 #ifdef TCP_NOPUSH 1342 /* 1343 * Turn off push flag to keep sender TCP from sending short packets 1344 * at the boundaries of each write(). Should probably do a SO_SNDBUF 1345 * to set the send buffer size as well, but that may not be desirable 1346 * in heavy-load situations. 1347 */ 1348 on = 1; 1349 if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, &on, sizeof(on)) < 0) 1350 syslog(LOG_WARNING, "setsockopt (TCP_NOPUSH): %m"); 1351 #endif 1352 #ifdef SO_SNDBUF 1353 on = 65536; 1354 if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, &on, sizeof(on)) < 0) 1355 syslog(LOG_WARNING, "setsockopt (SO_SNDBUF): %m"); 1356 #endif 1357 1358 return (fdopen(s, mode)); 1359 bad: 1360 /* Return the real value of errno (close may change it) */ 1361 t = errno; 1362 sigprocmask (SIG_UNBLOCK, &allsigs, NULL); 1363 if (s >= 0) 1364 (void) close(s); 1365 errno = t; 1366 return (NULL); 1367 } 1368 1369 static FILE * 1370 dataconn(char *name, off_t size, char *mode) 1371 { 1372 char sizebuf[32]; 1373 FILE *file = NULL; 1374 int retry = 0; 1375 in_port_t *p; 1376 u_char *fa, *ha; 1377 size_t alen; 1378 int error; 1379 1380 file_size = size; 1381 byte_count = 0; 1382 if (size != (off_t) -1) { 1383 (void) snprintf(sizebuf, sizeof(sizebuf), " (%qd bytes)", 1384 size); 1385 } else 1386 sizebuf[0] = '\0'; 1387 if (pdata >= 0) { 1388 union sockunion from; 1389 int s; 1390 socklen_t fromlen = sizeof(from); 1391 1392 (void) alarm ((unsigned) timeout); 1393 s = accept(pdata, (struct sockaddr *)&from, &fromlen); 1394 (void) alarm (0); 1395 if (s < 0) { 1396 reply(425, "Can't open data connection."); 1397 (void) close(pdata); 1398 pdata = -1; 1399 return (NULL); 1400 } 1401 switch (from.su_family) { 1402 case AF_INET: 1403 p = (in_port_t *)&from.su_sin.sin_port; 1404 fa = (u_char *)&from.su_sin.sin_addr; 1405 ha = (u_char *)&his_addr.su_sin.sin_addr; 1406 alen = sizeof(struct in_addr); 1407 break; 1408 case AF_INET6: 1409 p = (in_port_t *)&from.su_sin6.sin6_port; 1410 fa = (u_char *)&from.su_sin6.sin6_addr; 1411 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1412 alen = sizeof(struct in6_addr); 1413 break; 1414 default: 1415 reply(425, "Can't build data connection: " 1416 "unknown address family"); 1417 (void) close(pdata); 1418 (void) close(s); 1419 pdata = -1; 1420 return (NULL); 1421 } 1422 if (from.su_family != his_addr.su_family || 1423 ntohs(*p) < IPPORT_RESERVED) { 1424 reply(425, "Can't build data connection: " 1425 "address family or port error"); 1426 (void) close(pdata); 1427 (void) close(s); 1428 pdata = -1; 1429 return (NULL); 1430 } 1431 if (portcheck && memcmp(fa, ha, alen) != 0) { 1432 reply(425, "Can't build data connection: " 1433 "illegal port number"); 1434 (void) close(pdata); 1435 (void) close(s); 1436 pdata = -1; 1437 return (NULL); 1438 } 1439 (void) close(pdata); 1440 pdata = s; 1441 reply(150, "Opening %s mode data connection for '%s'%s.", 1442 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1443 return (fdopen(pdata, mode)); 1444 } 1445 if (data >= 0) { 1446 reply(125, "Using existing data connection for '%s'%s.", 1447 name, sizebuf); 1448 usedefault = 1; 1449 return (fdopen(data, mode)); 1450 } 1451 if (usedefault) 1452 data_dest = his_addr; 1453 usedefault = 1; 1454 do { 1455 if (file != NULL) 1456 (void) fclose(file); 1457 file = getdatasock(mode); 1458 if (file == NULL) { 1459 char hbuf[MAXHOSTNAMELEN], pbuf[10]; 1460 1461 error = getnameinfo((struct sockaddr *)&data_source, 1462 data_source.su_len, hbuf, sizeof(hbuf), pbuf, 1463 sizeof(pbuf), NI_NUMERICHOST | NI_NUMERICSERV); 1464 if (error != 0) 1465 reply(425, "Can't create data socket: %s.", 1466 strerror(errno)); 1467 else 1468 reply(425, 1469 "Can't create data socket (%s,%s): %s.", 1470 hbuf, pbuf, strerror(errno)); 1471 return (NULL); 1472 } 1473 1474 /* 1475 * attempt to connect to reserved port on client machine; 1476 * this looks like an attack 1477 */ 1478 switch (data_dest.su_family) { 1479 case AF_INET: 1480 p = (in_port_t *)&data_dest.su_sin.sin_port; 1481 fa = (u_char *)&data_dest.su_sin.sin_addr; 1482 ha = (u_char *)&his_addr.su_sin.sin_addr; 1483 alen = sizeof(struct in_addr); 1484 break; 1485 case AF_INET6: 1486 p = (in_port_t *)&data_dest.su_sin6.sin6_port; 1487 fa = (u_char *)&data_dest.su_sin6.sin6_addr; 1488 ha = (u_char *)&his_addr.su_sin6.sin6_addr; 1489 alen = sizeof(struct in6_addr); 1490 break; 1491 default: 1492 reply(425, "Can't build data connection: " 1493 "unknown address family"); 1494 (void) fclose(file); 1495 pdata = -1; 1496 return (NULL); 1497 } 1498 if (data_dest.su_family != his_addr.su_family || 1499 ntohs(*p) < IPPORT_RESERVED || ntohs(*p) == 2049) { /* XXX */ 1500 reply(425, "Can't build data connection: " 1501 "address family or port error"); 1502 (void) fclose(file); 1503 return NULL; 1504 } 1505 if (portcheck && memcmp(fa, ha, alen) != 0) { 1506 reply(435, "Can't build data connection: " 1507 "illegal port number"); 1508 (void) fclose(file); 1509 return NULL; 1510 } 1511 1512 if (connect(fileno(file), (struct sockaddr *)&data_dest, 1513 data_dest.su_len) == 0) { 1514 reply(150, "Opening %s mode data connection for '%s'%s.", 1515 type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); 1516 data = fileno(file); 1517 return (file); 1518 } 1519 if (errno != EADDRINUSE) 1520 break; 1521 sleep((unsigned) swaitint); 1522 retry += swaitint; 1523 } while (retry <= swaitmax); 1524 perror_reply(425, "Can't build data connection"); 1525 (void) fclose(file); 1526 return (NULL); 1527 } 1528 1529 /* 1530 * Transfer the contents of "instr" to "outstr" peer using the appropriate 1531 * encapsulation of the data subject to Mode, Structure, and Type. 1532 * 1533 * NB: Form isn't handled. 1534 */ 1535 static int 1536 send_data(FILE *instr, FILE *outstr, off_t blksize, off_t filesize, int isreg) 1537 { 1538 int c, cnt, filefd, netfd; 1539 char *buf, *bp; 1540 size_t len; 1541 1542 transflag++; 1543 switch (type) { 1544 1545 case TYPE_A: 1546 while ((c = getc(instr)) != EOF) { 1547 if (recvurg) 1548 goto got_oob; 1549 byte_count++; 1550 if (c == '\n') { 1551 if (ferror(outstr)) 1552 goto data_err; 1553 (void) putc('\r', outstr); 1554 } 1555 (void) putc(c, outstr); 1556 } 1557 fflush(outstr); 1558 transflag = 0; 1559 if (ferror(instr)) 1560 goto file_err; 1561 if (ferror(outstr)) 1562 goto data_err; 1563 reply(226, "Transfer complete."); 1564 return(0); 1565 1566 case TYPE_I: 1567 case TYPE_L: 1568 /* 1569 * isreg is only set if we are not doing restart and we 1570 * are sending a regular file 1571 */ 1572 netfd = fileno(outstr); 1573 filefd = fileno(instr); 1574 1575 if (isreg && filesize < (off_t)16 * 1024 * 1024) { 1576 size_t fsize = (size_t)filesize; 1577 1578 buf = mmap(0, fsize, PROT_READ, MAP_SHARED, filefd, 1579 (off_t)0); 1580 if (buf == MAP_FAILED) { 1581 syslog(LOG_WARNING, "mmap(%llu): %m", 1582 (unsigned long long)fsize); 1583 goto oldway; 1584 } 1585 bp = buf; 1586 len = fsize; 1587 do { 1588 cnt = write(netfd, bp, len); 1589 if (recvurg) { 1590 munmap(buf, fsize); 1591 goto got_oob; 1592 } 1593 len -= cnt; 1594 bp += cnt; 1595 if (cnt > 0) 1596 byte_count += cnt; 1597 } while(cnt > 0 && len > 0); 1598 1599 transflag = 0; 1600 munmap(buf, fsize); 1601 if (cnt < 0) 1602 goto data_err; 1603 reply(226, "Transfer complete."); 1604 return(0); 1605 } 1606 1607 oldway: 1608 if ((buf = malloc((size_t)blksize)) == NULL) { 1609 transflag = 0; 1610 perror_reply(451, "Local resource failure: malloc"); 1611 return(-1); 1612 } 1613 1614 while ((cnt = read(filefd, buf, (size_t)blksize)) > 0 && 1615 write(netfd, buf, cnt) == cnt) 1616 byte_count += cnt; 1617 transflag = 0; 1618 (void)free(buf); 1619 if (cnt != 0) { 1620 if (cnt < 0) 1621 goto file_err; 1622 goto data_err; 1623 } 1624 reply(226, "Transfer complete."); 1625 return(0); 1626 default: 1627 transflag = 0; 1628 reply(550, "Unimplemented TYPE %d in send_data", type); 1629 return(-1); 1630 } 1631 1632 data_err: 1633 transflag = 0; 1634 reply(426, "Data connection"); 1635 return(-1); 1636 1637 file_err: 1638 transflag = 0; 1639 reply(551, "Error on input file"); 1640 return(-1); 1641 1642 got_oob: 1643 myoob(); 1644 recvurg = 0; 1645 transflag = 0; 1646 return(-1); 1647 } 1648 1649 /* 1650 * Transfer data from peer to "outstr" using the appropriate encapulation of 1651 * the data subject to Mode, Structure, and Type. 1652 * 1653 * N.B.: Form isn't handled. 1654 */ 1655 static int 1656 receive_data(FILE *instr, FILE *outstr) 1657 { 1658 int c; 1659 int cnt; 1660 char buf[BUFSIZ]; 1661 struct sigaction sa, sa_saved; 1662 volatile int bare_lfs = 0; 1663 1664 transflag++; 1665 switch (type) { 1666 1667 case TYPE_I: 1668 case TYPE_L: 1669 memset(&sa, 0, sizeof(sa)); 1670 sigfillset(&sa.sa_mask); 1671 sa.sa_flags = SA_RESTART; 1672 sa.sa_handler = lostconn; 1673 (void) sigaction(SIGALRM, &sa, &sa_saved); 1674 do { 1675 (void) alarm ((unsigned) timeout); 1676 cnt = read(fileno(instr), buf, sizeof(buf)); 1677 (void) alarm (0); 1678 if (recvurg) 1679 goto got_oob; 1680 1681 if (cnt > 0) { 1682 if (write(fileno(outstr), buf, cnt) != cnt) 1683 goto file_err; 1684 byte_count += cnt; 1685 } 1686 } while (cnt > 0); 1687 (void) sigaction(SIGALRM, &sa_saved, NULL); 1688 if (cnt < 0) 1689 goto data_err; 1690 transflag = 0; 1691 return (0); 1692 1693 case TYPE_E: 1694 reply(553, "TYPE E not implemented."); 1695 transflag = 0; 1696 return (-1); 1697 1698 case TYPE_A: 1699 while ((c = getc(instr)) != EOF) { 1700 if (recvurg) 1701 goto got_oob; 1702 byte_count++; 1703 if (c == '\n') 1704 bare_lfs++; 1705 while (c == '\r') { 1706 if (ferror(outstr)) 1707 goto data_err; 1708 if ((c = getc(instr)) != '\n') { 1709 (void) putc ('\r', outstr); 1710 if (c == '\0' || c == EOF) 1711 goto contin2; 1712 } 1713 } 1714 (void) putc(c, outstr); 1715 contin2: ; 1716 } 1717 fflush(outstr); 1718 if (ferror(instr)) 1719 goto data_err; 1720 if (ferror(outstr)) 1721 goto file_err; 1722 transflag = 0; 1723 if (bare_lfs) { 1724 lreply(226, 1725 "WARNING! %d bare linefeeds received in ASCII mode", 1726 bare_lfs); 1727 printf(" File may not have transferred correctly.\r\n"); 1728 } 1729 return (0); 1730 default: 1731 reply(550, "Unimplemented TYPE %d in receive_data", type); 1732 transflag = 0; 1733 return (-1); 1734 } 1735 1736 data_err: 1737 transflag = 0; 1738 reply(426, "Data Connection"); 1739 return (-1); 1740 1741 file_err: 1742 transflag = 0; 1743 reply(452, "Error writing file"); 1744 return (-1); 1745 1746 got_oob: 1747 myoob(); 1748 recvurg = 0; 1749 transflag = 0; 1750 return (-1); 1751 } 1752 1753 void 1754 statfilecmd(char *filename) 1755 { 1756 FILE *fin; 1757 int c; 1758 int atstart; 1759 char line[LINE_MAX]; 1760 1761 (void)snprintf(line, sizeof(line), "/bin/ls -lgA %s", filename); 1762 fin = ftpd_popen(line, "r"); 1763 if (fin == NULL) { 1764 reply(451, "Local resource failure"); 1765 return; 1766 } 1767 lreply(211, "status of %s:", filename); 1768 atstart = 1; 1769 while ((c = getc(fin)) != EOF) { 1770 if (c == '\n') { 1771 if (ferror(stdout)){ 1772 perror_reply(421, "control connection"); 1773 (void) ftpd_pclose(fin); 1774 dologout(1); 1775 /* NOTREACHED */ 1776 } 1777 if (ferror(fin)) { 1778 perror_reply(551, filename); 1779 (void) ftpd_pclose(fin); 1780 return; 1781 } 1782 (void) putc('\r', stdout); 1783 } 1784 if (atstart && isdigit(c)) 1785 (void) putc(' ', stdout); 1786 (void) putc(c, stdout); 1787 atstart = (c == '\n'); 1788 } 1789 (void) ftpd_pclose(fin); 1790 reply(211, "End of Status"); 1791 } 1792 1793 void 1794 statcmd(void) 1795 { 1796 union sockunion *su; 1797 u_char *a, *p; 1798 char hbuf[MAXHOSTNAMELEN]; 1799 int ispassive; 1800 int error; 1801 1802 lreply(211, "%s FTP server status:", hostname); 1803 error = getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len, 1804 hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST); 1805 printf(" Connected to %s", remotehost); 1806 if (error == 0 && strcmp(remotehost, hbuf) != 0) 1807 printf(" (%s)", hbuf); 1808 printf("\r\n"); 1809 if (logged_in) { 1810 if (guest) 1811 printf(" Logged in anonymously\r\n"); 1812 else 1813 printf(" Logged in as %s\r\n", pw->pw_name); 1814 } else if (askpasswd) 1815 printf(" Waiting for password\r\n"); 1816 else 1817 printf(" Waiting for user name\r\n"); 1818 printf(" TYPE: %s", typenames[type]); 1819 if (type == TYPE_A || type == TYPE_E) 1820 printf(", FORM: %s", formnames[form]); 1821 if (type == TYPE_L) 1822 #if NBBY == 8 1823 printf(" %d", NBBY); 1824 #else 1825 printf(" %d", bytesize); /* need definition! */ 1826 #endif 1827 printf("; STRUcture: %s; transfer MODE: %s\r\n", 1828 strunames[stru], modenames[mode]); 1829 ispassive = 0; 1830 if (data != -1) 1831 printf(" Data connection open\r\n"); 1832 else if (pdata != -1) { 1833 printf(" in Passive mode\r\n"); 1834 su = (union sockunion *)&pasv_addr; 1835 ispassive++; 1836 goto printaddr; 1837 } else if (usedefault == 0) { 1838 size_t alen; 1839 int af, i; 1840 1841 su = (union sockunion *)&data_dest; 1842 printaddr: 1843 /* PASV/PORT */ 1844 if (su->su_family == AF_INET) { 1845 if (ispassive) 1846 printf("211- PASV "); 1847 else 1848 printf("211- PORT "); 1849 a = (u_char *)&su->su_sin.sin_addr; 1850 p = (u_char *)&su->su_sin.sin_port; 1851 printf("(%u,%u,%u,%u,%u,%u)\r\n", 1852 a[0], a[1], a[2], a[3], 1853 p[0], p[1]); 1854 } 1855 1856 /* LPSV/LPRT */ 1857 alen = 0; 1858 switch (su->su_family) { 1859 case AF_INET: 1860 a = (u_char *)&su->su_sin.sin_addr; 1861 p = (u_char *)&su->su_sin.sin_port; 1862 alen = sizeof(su->su_sin.sin_addr); 1863 af = 4; 1864 break; 1865 case AF_INET6: 1866 a = (u_char *)&su->su_sin6.sin6_addr; 1867 p = (u_char *)&su->su_sin6.sin6_port; 1868 alen = sizeof(su->su_sin6.sin6_addr); 1869 af = 6; 1870 break; 1871 default: 1872 af = 0; 1873 break; 1874 } 1875 if (af) { 1876 if (ispassive) 1877 printf("211- LPSV "); 1878 else 1879 printf("211- LPRT "); 1880 printf("(%u,%llu", af, (unsigned long long)alen); 1881 for (i = 0; i < alen; i++) 1882 printf(",%u", a[i]); 1883 printf(",%u,%u,%u)\r\n", 2, p[0], p[1]); 1884 } 1885 1886 /* EPRT/EPSV */ 1887 switch (su->su_family) { 1888 case AF_INET: 1889 af = 1; 1890 break; 1891 case AF_INET6: 1892 af = 2; 1893 break; 1894 default: 1895 af = 0; 1896 break; 1897 } 1898 if (af) { 1899 char pbuf[10]; 1900 union sockunion tmp = *su; 1901 1902 if (tmp.su_family == AF_INET6) 1903 tmp.su_sin6.sin6_scope_id = 0; 1904 if (getnameinfo((struct sockaddr *)&tmp, tmp.su_len, 1905 hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), 1906 NI_NUMERICHOST | NI_NUMERICSERV) == 0) { 1907 if (ispassive) 1908 printf("211- EPSV "); 1909 else 1910 printf("211- EPRT "); 1911 printf("(|%u|%s|%s|)\r\n", 1912 af, hbuf, pbuf); 1913 } 1914 } 1915 } else 1916 printf(" No data connection\r\n"); 1917 reply(211, "End of status"); 1918 } 1919 1920 void 1921 fatal(char *s) 1922 { 1923 1924 reply(451, "Error in server: %s", s); 1925 reply(221, "Closing connection due to server error."); 1926 dologout(0); 1927 /* NOTREACHED */ 1928 } 1929 1930 void 1931 reply(int n, const char *fmt, ...) 1932 { 1933 char *buf, *p, *next; 1934 int rval; 1935 va_list ap; 1936 1937 va_start(ap, fmt); 1938 rval = vasprintf(&buf, fmt, ap); 1939 va_end(ap); 1940 if (rval == -1 || buf == NULL) { 1941 printf("421 Local resource failure: malloc\r\n"); 1942 fflush(stdout); 1943 dologout(1); 1944 } 1945 next = buf; 1946 while ((p = strsep(&next, "\n\r"))) { 1947 printf("%d%s %s\r\n", n, (next != '\0') ? "-" : "", p); 1948 if (debug) 1949 syslog(LOG_DEBUG, "<--- %d%s %s", n, 1950 (next != '\0') ? "-" : "", p); 1951 } 1952 (void)fflush(stdout); 1953 free(buf); 1954 } 1955 1956 1957 void 1958 reply_r(int n, const char *fmt, ...) 1959 { 1960 char *p, *next; 1961 char msg[BUFSIZ]; 1962 char buf[BUFSIZ]; 1963 va_list ap; 1964 struct syslog_data sdata = SYSLOG_DATA_INIT; 1965 1966 sdata.log_fac = LOG_FTP; 1967 va_start(ap, fmt); 1968 vsnprintf(msg, sizeof(msg), fmt, ap); 1969 va_end(ap); 1970 1971 next = msg; 1972 1973 while ((p = strsep(&next, "\n\r"))) { 1974 snprintf(buf, sizeof(buf), "%d%s %s\r\n", n, 1975 (next != '\0') ? "-" : "", p); 1976 write(STDOUT_FILENO, buf, strlen(buf)); 1977 if (debug) { 1978 buf[strlen(buf) - 2] = '\0'; 1979 syslog_r(LOG_DEBUG, &sdata, "<--- %s", buf); 1980 } 1981 } 1982 } 1983 1984 void 1985 lreply(int n, const char *fmt, ...) 1986 { 1987 va_list ap; 1988 1989 va_start(ap, fmt); 1990 (void)printf("%d- ", n); 1991 (void)vprintf(fmt, ap); 1992 va_end(ap); 1993 (void)printf("\r\n"); 1994 (void)fflush(stdout); 1995 if (debug) { 1996 va_start(ap, fmt); 1997 syslog(LOG_DEBUG, "<--- %d- ", n); 1998 vsyslog(LOG_DEBUG, fmt, ap); 1999 va_end(ap); 2000 } 2001 } 2002 2003 static void 2004 ack(char *s) 2005 { 2006 2007 reply(250, "%s command successful.", s); 2008 } 2009 2010 void 2011 nack(char *s) 2012 { 2013 2014 reply(502, "%s command not implemented.", s); 2015 } 2016 2017 /* ARGSUSED */ 2018 void 2019 yyerror(char *s) 2020 { 2021 cbuf[strcspn(cbuf, "\n")] = '\0'; 2022 reply(500, "'%s': command not understood.", cbuf); 2023 } 2024 2025 void 2026 delete(char *name) 2027 { 2028 struct stat st; 2029 2030 LOGCMD("delete", name); 2031 if (stat(name, &st) < 0) { 2032 perror_reply(550, name); 2033 return; 2034 } 2035 if ((st.st_mode&S_IFMT) == S_IFDIR) { 2036 if (rmdir(name) < 0) { 2037 perror_reply(550, name); 2038 return; 2039 } 2040 goto done; 2041 } 2042 if (unlink(name) < 0) { 2043 perror_reply(550, name); 2044 return; 2045 } 2046 done: 2047 ack("DELE"); 2048 } 2049 2050 void 2051 cwd(char *path) 2052 { 2053 FILE *message; 2054 2055 if (chdir(path) < 0) 2056 perror_reply(550, path); 2057 else { 2058 if ((message = fopen(_PATH_CWDMESG, "r")) != NULL) { 2059 char line[LINE_MAX]; 2060 2061 while (fgets(line, sizeof(line), message) != NULL) { 2062 line[strcspn(line, "\n")] = '\0'; 2063 lreply(250, "%s", line); 2064 } 2065 (void) fflush(stdout); 2066 (void) fclose(message); 2067 } 2068 ack("CWD"); 2069 } 2070 } 2071 2072 void 2073 replydirname(const char *name, const char *message) 2074 { 2075 char *p, *ep; 2076 char npath[MAXPATHLEN * 2]; 2077 2078 p = npath; 2079 ep = &npath[sizeof(npath) - 1]; 2080 while (*name) { 2081 if (*name == '"') { 2082 if (ep - p < 2) 2083 break; 2084 *p++ = *name++; 2085 *p++ = '"'; 2086 } else { 2087 if (ep - p < 1) 2088 break; 2089 *p++ = *name++; 2090 } 2091 } 2092 *p = '\0'; 2093 reply(257, "\"%s\" %s", npath, message); 2094 } 2095 2096 void 2097 makedir(char *name) 2098 { 2099 2100 LOGCMD("mkdir", name); 2101 if (mkdir(name, 0777) < 0) 2102 perror_reply(550, name); 2103 else 2104 replydirname(name, "directory created."); 2105 } 2106 2107 void 2108 removedir(char *name) 2109 { 2110 2111 LOGCMD("rmdir", name); 2112 if (rmdir(name) < 0) 2113 perror_reply(550, name); 2114 else 2115 ack("RMD"); 2116 } 2117 2118 void 2119 pwd(void) 2120 { 2121 char path[MAXPATHLEN]; 2122 2123 if (getcwd(path, sizeof(path)) == NULL) 2124 perror_reply(550, "Can't get current directory"); 2125 else 2126 replydirname(path, "is current directory."); 2127 } 2128 2129 char * 2130 renamefrom(char *name) 2131 { 2132 struct stat st; 2133 2134 if (stat(name, &st) < 0) { 2135 perror_reply(550, name); 2136 return ((char *)0); 2137 } 2138 reply(350, "File exists, ready for destination name"); 2139 return (name); 2140 } 2141 2142 void 2143 renamecmd(char *from, char *to) 2144 { 2145 2146 LOGCMD2("rename", from, to); 2147 if (rename(from, to) < 0) 2148 perror_reply(550, "rename"); 2149 else 2150 ack("RNTO"); 2151 } 2152 2153 static void 2154 dolog(struct sockaddr *sa) 2155 { 2156 char hbuf[sizeof(remotehost)]; 2157 2158 if (getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), NULL, 0, 0) == 0) 2159 (void) strlcpy(remotehost, hbuf, sizeof(remotehost)); 2160 else 2161 (void) strlcpy(remotehost, "unknown", sizeof(remotehost)); 2162 2163 #ifdef HASSETPROCTITLE 2164 snprintf(proctitle, sizeof(proctitle), "%s: connected", remotehost); 2165 setproctitle("%s", proctitle); 2166 #endif /* HASSETPROCTITLE */ 2167 2168 if (logging) { 2169 int error; 2170 error = getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), 2171 NULL, 0, NI_NUMERICHOST); 2172 syslog(LOG_INFO, "connection from %s [%s]", remotehost, 2173 error ? gai_strerror(error) : hbuf); 2174 } 2175 } 2176 2177 /* 2178 * Record logout in wtmp file and exit with supplied status. 2179 * NOTE: because this is called from signal handlers it cannot 2180 * use stdio (or call other functions that use stdio). 2181 */ 2182 void 2183 dologout(int status) 2184 { 2185 2186 transflag = 0; 2187 2188 if (logged_in) { 2189 sigprocmask(SIG_BLOCK, &allsigs, NULL); 2190 ftpdlogwtmp(ttyline, "", ""); 2191 if (doutmp) 2192 ftpd_logout(utmp.ut_line); 2193 } 2194 /* beware of flushing buffers after a SIGPIPE */ 2195 _exit(status); 2196 } 2197 2198 /*ARGSUSED*/ 2199 static void 2200 sigurg(int signo) 2201 { 2202 2203 recvurg = 1; 2204 } 2205 2206 static void 2207 myoob(void) 2208 { 2209 char *cp; 2210 int ret; 2211 2212 /* only process if transfer occurring */ 2213 if (!transflag) 2214 return; 2215 cp = tmpline; 2216 ret = getline(cp, 7, stdin); 2217 if (ret == -1) { 2218 reply(221, "You could at least say goodbye."); 2219 dologout(0); 2220 } else if (ret == -2) { 2221 /* Ignore truncated command */ 2222 return; 2223 } 2224 upper(cp); 2225 if (strcmp(cp, "ABOR\r\n") == 0) { 2226 tmpline[0] = '\0'; 2227 reply(426, "Transfer aborted. Data connection closed."); 2228 reply(226, "Abort successful"); 2229 } 2230 if (strcmp(cp, "STAT\r\n") == 0) { 2231 tmpline[0] = '\0'; 2232 if (file_size != (off_t) -1) 2233 reply(213, "Status: %qd of %qd bytes transferred", 2234 byte_count, file_size); 2235 else 2236 reply(213, "Status: %qd bytes transferred", byte_count); 2237 } 2238 } 2239 2240 /* 2241 * Note: a response of 425 is not mentioned as a possible response to 2242 * the PASV command in RFC959. However, it has been blessed as 2243 * a legitimate response by Jon Postel in a telephone conversation 2244 * with Rick Adams on 25 Jan 89. 2245 */ 2246 void 2247 passive(void) 2248 { 2249 socklen_t len; 2250 int on = 1; 2251 u_char *p, *a; 2252 2253 if (pw == NULL) { 2254 reply(530, "Please login with USER and PASS"); 2255 return; 2256 } 2257 if (pdata >= 0) 2258 close(pdata); 2259 /* 2260 * XXX 2261 * At this point, it would be nice to have an algorithm that 2262 * inserted a growing delay in an attack scenario. Such a thing 2263 * would look like continual passive sockets being opened, but 2264 * nothing serious being done with them. They're not used to 2265 * move data; the entire attempt is just to use tcp FIN_WAIT 2266 * resources. 2267 */ 2268 pdata = socket(AF_INET, SOCK_STREAM, 0); 2269 if (pdata < 0) { 2270 perror_reply(425, "Can't open passive connection"); 2271 return; 2272 } 2273 2274 if (setsockopt(pdata, SOL_SOCKET, SO_KEEPALIVE, 2275 &on, sizeof(on)) < 0) 2276 goto pasv_error; 2277 2278 on = IP_PORTRANGE_HIGH; 2279 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2280 &on, sizeof(on)) < 0) 2281 goto pasv_error; 2282 2283 pasv_addr = ctrl_addr; 2284 pasv_addr.su_sin.sin_port = 0; 2285 if (bind(pdata, (struct sockaddr *)&pasv_addr, 2286 pasv_addr.su_len) < 0) 2287 goto pasv_error; 2288 2289 len = sizeof(pasv_addr); 2290 if (getsockname(pdata, (struct sockaddr *)&pasv_addr, &len) < 0) 2291 goto pasv_error; 2292 if (listen(pdata, 1) < 0) 2293 goto pasv_error; 2294 a = (u_char *)&pasv_addr.su_sin.sin_addr; 2295 p = (u_char *)&pasv_addr.su_sin.sin_port; 2296 2297 reply(227, "Entering Passive Mode (%u,%u,%u,%u,%u,%u)", a[0], 2298 a[1], a[2], a[3], p[0], p[1]); 2299 return; 2300 2301 pasv_error: 2302 perror_reply(425, "Can't open passive connection"); 2303 (void) close(pdata); 2304 pdata = -1; 2305 return; 2306 } 2307 2308 int 2309 epsvproto2af(int proto) 2310 { 2311 2312 switch (proto) { 2313 case 1: return AF_INET; 2314 #ifdef INET6 2315 case 2: return AF_INET6; 2316 #endif 2317 default: return -1; 2318 } 2319 } 2320 2321 int 2322 af2epsvproto(int af) 2323 { 2324 2325 switch (af) { 2326 case AF_INET: return 1; 2327 #ifdef INET6 2328 case AF_INET6: return 2; 2329 #endif 2330 default: return -1; 2331 } 2332 } 2333 2334 /* 2335 * 228 Entering Long Passive Mode (af, hal, h1, h2, h3,..., pal, p1, p2...) 2336 * 229 Entering Extended Passive Mode (|||port|) 2337 */ 2338 void 2339 long_passive(char *cmd, int pf) 2340 { 2341 socklen_t len; 2342 int on = 1; 2343 u_char *p, *a; 2344 2345 if (!logged_in) { 2346 syslog(LOG_NOTICE, "long passive but not logged in"); 2347 reply(503, "Login with USER first."); 2348 return; 2349 } 2350 2351 if (pf != PF_UNSPEC && ctrl_addr.su_family != pf) { 2352 /* 2353 * XXX 2354 * only EPRT/EPSV ready clients will understand this 2355 */ 2356 if (strcmp(cmd, "EPSV") != 0) 2357 reply(501, "Network protocol mismatch"); /*XXX*/ 2358 else 2359 epsv_protounsupp("Network protocol mismatch"); 2360 2361 return; 2362 } 2363 2364 if (pdata >= 0) 2365 close(pdata); 2366 /* 2367 * XXX 2368 * At this point, it would be nice to have an algorithm that 2369 * inserted a growing delay in an attack scenario. Such a thing 2370 * would look like continual passive sockets being opened, but 2371 * nothing serious being done with them. They not used to move 2372 * data; the entire attempt is just to use tcp FIN_WAIT 2373 * resources. 2374 */ 2375 pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0); 2376 if (pdata < 0) { 2377 perror_reply(425, "Can't open passive connection"); 2378 return; 2379 } 2380 2381 if (setsockopt(pdata, SOL_SOCKET, SO_KEEPALIVE, 2382 &on, sizeof(on)) < 0) 2383 goto pasv_error; 2384 2385 switch (ctrl_addr.su_family) { 2386 case AF_INET: 2387 on = IP_PORTRANGE_HIGH; 2388 if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE, 2389 &on, sizeof(on)) < 0) 2390 goto pasv_error; 2391 break; 2392 case AF_INET6: 2393 on = IPV6_PORTRANGE_HIGH; 2394 if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE, 2395 &on, sizeof(on)) < 0) 2396 goto pasv_error; 2397 break; 2398 } 2399 2400 pasv_addr = ctrl_addr; 2401 pasv_addr.su_port = 0; 2402 if (bind(pdata, (struct sockaddr *)&pasv_addr, pasv_addr.su_len) < 0) 2403 goto pasv_error; 2404 len = pasv_addr.su_len; 2405 if (getsockname(pdata, (struct sockaddr *)&pasv_addr, &len) < 0) 2406 goto pasv_error; 2407 if (listen(pdata, 1) < 0) 2408 goto pasv_error; 2409 p = (u_char *)&pasv_addr.su_port; 2410 2411 if (strcmp(cmd, "LPSV") == 0) { 2412 switch (pasv_addr.su_family) { 2413 case AF_INET: 2414 a = (u_char *)&pasv_addr.su_sin.sin_addr; 2415 reply(228, 2416 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2417 4, 4, a[0], a[1], a[2], a[3], 2, p[0], p[1]); 2418 return; 2419 case AF_INET6: 2420 a = (u_char *)&pasv_addr.su_sin6.sin6_addr; 2421 reply(228, 2422 "Entering Long Passive Mode (%u,%u,%u,%u,%u,%u," 2423 "%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u)", 2424 6, 16, a[0], a[1], a[2], a[3], a[4], 2425 a[5], a[6], a[7], a[8], a[9], a[10], 2426 a[11], a[12], a[13], a[14], a[15], 2427 2, p[0], p[1]); 2428 return; 2429 } 2430 } else if (strcmp(cmd, "EPSV") == 0) { 2431 switch (pasv_addr.su_family) { 2432 case AF_INET: 2433 case AF_INET6: 2434 reply(229, "Entering Extended Passive Mode (|||%u|)", 2435 ntohs(pasv_addr.su_port)); 2436 return; 2437 } 2438 } else { 2439 /* more proper error code? */ 2440 } 2441 2442 pasv_error: 2443 perror_reply(425, "Can't open passive connection"); 2444 (void) close(pdata); 2445 pdata = -1; 2446 return; 2447 } 2448 2449 /* 2450 * EPRT |proto|addr|port| 2451 */ 2452 int 2453 extended_port(const char *arg) 2454 { 2455 char *tmp = NULL; 2456 char *result[3]; 2457 char *p, *q; 2458 char delim; 2459 struct addrinfo hints; 2460 struct addrinfo *res = NULL; 2461 int i; 2462 unsigned long proto; 2463 2464 if (epsvall) { 2465 reply(501, "EPRT disallowed after EPSV ALL"); 2466 return -1; 2467 } 2468 2469 usedefault = 0; 2470 if (pdata >= 0) { 2471 (void) close(pdata); 2472 pdata = -1; 2473 } 2474 2475 tmp = strdup(arg); 2476 if (!tmp) { 2477 fatal("not enough core."); 2478 /*NOTREACHED*/ 2479 } 2480 p = tmp; 2481 delim = p[0]; 2482 p++; 2483 memset(result, 0, sizeof(result)); 2484 for (i = 0; i < 3; i++) { 2485 q = strchr(p, delim); 2486 if (!q || *q != delim) 2487 goto parsefail; 2488 *q++ = '\0'; 2489 result[i] = p; 2490 p = q; 2491 } 2492 2493 /* some more sanity check */ 2494 p = NULL; 2495 (void)strtoul(result[2], &p, 10); 2496 if (!*result[2] || *p) 2497 goto protounsupp; 2498 p = NULL; 2499 proto = strtoul(result[0], &p, 10); 2500 if (!*result[0] || *p) 2501 goto protounsupp; 2502 2503 memset(&hints, 0, sizeof(hints)); 2504 hints.ai_family = epsvproto2af((int)proto); 2505 if (hints.ai_family < 0) 2506 goto protounsupp; 2507 hints.ai_socktype = SOCK_STREAM; 2508 hints.ai_flags = AI_NUMERICHOST; /*no DNS*/ 2509 if (getaddrinfo(result[1], result[2], &hints, &res)) 2510 goto parsefail; 2511 if (res->ai_next) 2512 goto parsefail; 2513 if (sizeof(data_dest) < res->ai_addrlen) 2514 goto parsefail; 2515 memcpy(&data_dest, res->ai_addr, res->ai_addrlen); 2516 if (his_addr.su_family == AF_INET6 && 2517 data_dest.su_family == AF_INET6) { 2518 /* XXX more sanity checks! */ 2519 data_dest.su_sin6.sin6_scope_id = 2520 his_addr.su_sin6.sin6_scope_id; 2521 } 2522 if (pdata >= 0) { 2523 (void) close(pdata); 2524 pdata = -1; 2525 } 2526 reply(200, "EPRT command successful."); 2527 2528 if (tmp) 2529 free(tmp); 2530 if (res) 2531 freeaddrinfo(res); 2532 return 0; 2533 2534 parsefail: 2535 reply(500, "Invalid argument, rejected."); 2536 usedefault = 1; 2537 if (tmp) 2538 free(tmp); 2539 if (res) 2540 freeaddrinfo(res); 2541 return -1; 2542 2543 protounsupp: 2544 epsv_protounsupp("Protocol not supported"); 2545 usedefault = 1; 2546 if (tmp) 2547 free(tmp); 2548 if (res) 2549 freeaddrinfo(res); 2550 return -1; 2551 } 2552 2553 /* 2554 * 522 Protocol not supported (proto,...) 2555 * as we assume address family for control and data connections are the same, 2556 * we do not return the list of address families we support - instead, we 2557 * return the address family of the control connection. 2558 */ 2559 void 2560 epsv_protounsupp(const char *message) 2561 { 2562 int proto; 2563 2564 proto = af2epsvproto(ctrl_addr.su_family); 2565 if (proto < 0) 2566 reply(501, "%s", message); /*XXX*/ 2567 else 2568 reply(522, "%s, use (%d)", message, proto); 2569 } 2570 2571 /* 2572 * Generate unique name for file with basename "local". 2573 * The file named "local" is already known to exist. 2574 * Generates failure reply on error. 2575 */ 2576 static int 2577 guniquefd(char *local, char **nam) 2578 { 2579 static char new[MAXPATHLEN]; 2580 struct stat st; 2581 int count, len, fd; 2582 char *cp; 2583 2584 cp = strrchr(local, '/'); 2585 if (cp) 2586 *cp = '\0'; 2587 if (stat(cp ? local : ".", &st) < 0) { 2588 perror_reply(553, cp ? local : "."); 2589 return (-1); 2590 } 2591 if (cp) 2592 *cp = '/'; 2593 len = strlcpy(new, local, sizeof(new)); 2594 if (len+2+1 >= sizeof(new)-1) 2595 return (-1); 2596 cp = new + len; 2597 *cp++ = '.'; 2598 for (count = 1; count < 100; count++) { 2599 (void)snprintf(cp, sizeof(new) - (cp - new), "%d", count); 2600 fd = open(new, O_RDWR|O_CREAT|O_EXCL, 0666); 2601 if (fd == -1) 2602 continue; 2603 if (nam) 2604 *nam = new; 2605 return (fd); 2606 } 2607 reply(452, "Unique file name cannot be created."); 2608 return (-1); 2609 } 2610 2611 /* 2612 * Format and send reply containing system error number. 2613 */ 2614 void 2615 perror_reply(int code, char *string) 2616 { 2617 2618 reply(code, "%s: %s.", string, strerror(errno)); 2619 } 2620 2621 static char *onefile[] = { 2622 "", 2623 0 2624 }; 2625 2626 void 2627 send_file_list(char *whichf) 2628 { 2629 struct stat st; 2630 DIR *dirp = NULL; 2631 struct dirent *dir; 2632 FILE *dout = NULL; 2633 char **dirlist; 2634 char *dirname; 2635 int simple = 0; 2636 volatile int freeglob = 0; 2637 glob_t gl; 2638 2639 if (strpbrk(whichf, "~{[*?") != NULL) { 2640 memset(&gl, 0, sizeof(gl)); 2641 freeglob = 1; 2642 if (glob(whichf, 2643 GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE|GLOB_LIMIT, 2644 0, &gl)) { 2645 reply(550, "not found"); 2646 goto out; 2647 } else if (gl.gl_pathc == 0) { 2648 errno = ENOENT; 2649 perror_reply(550, whichf); 2650 goto out; 2651 } 2652 dirlist = gl.gl_pathv; 2653 } else { 2654 onefile[0] = whichf; 2655 dirlist = onefile; 2656 simple = 1; 2657 } 2658 2659 while ((dirname = *dirlist++)) { 2660 if (stat(dirname, &st) < 0) { 2661 /* 2662 * If user typed "ls -l", etc, and the client 2663 * used NLST, do what the user meant. 2664 */ 2665 if (dirname[0] == '-' && *dirlist == NULL && 2666 transflag == 0) { 2667 retrieve("/bin/ls %s", dirname); 2668 goto out; 2669 } 2670 perror_reply(550, whichf); 2671 if (dout != NULL) { 2672 (void) fclose(dout); 2673 transflag = 0; 2674 data = -1; 2675 pdata = -1; 2676 } 2677 goto out; 2678 } 2679 2680 if (S_ISREG(st.st_mode)) { 2681 if (dout == NULL) { 2682 dout = dataconn("file list", (off_t)-1, "w"); 2683 if (dout == NULL) 2684 goto out; 2685 transflag++; 2686 } 2687 fprintf(dout, "%s%s\n", dirname, 2688 type == TYPE_A ? "\r" : ""); 2689 byte_count += strlen(dirname) + 1; 2690 continue; 2691 } else if (!S_ISDIR(st.st_mode)) 2692 continue; 2693 2694 if ((dirp = opendir(dirname)) == NULL) 2695 continue; 2696 2697 while ((dir = readdir(dirp)) != NULL) { 2698 char nbuf[MAXPATHLEN]; 2699 2700 if (recvurg) { 2701 myoob(); 2702 recvurg = 0; 2703 transflag = 0; 2704 goto out; 2705 } 2706 2707 if (dir->d_name[0] == '.' && dir->d_namlen == 1) 2708 continue; 2709 if (dir->d_name[0] == '.' && dir->d_name[1] == '.' && 2710 dir->d_namlen == 2) 2711 continue; 2712 2713 snprintf(nbuf, sizeof(nbuf), "%s/%s", dirname, 2714 dir->d_name); 2715 2716 /* 2717 * We have to do a stat to insure it's 2718 * not a directory or special file. 2719 */ 2720 if (simple || (stat(nbuf, &st) == 0 && 2721 S_ISREG(st.st_mode))) { 2722 if (dout == NULL) { 2723 dout = dataconn("file list", (off_t)-1, 2724 "w"); 2725 if (dout == NULL) 2726 goto out; 2727 transflag++; 2728 } 2729 if (nbuf[0] == '.' && nbuf[1] == '/') 2730 fprintf(dout, "%s%s\n", &nbuf[2], 2731 type == TYPE_A ? "\r" : ""); 2732 else 2733 fprintf(dout, "%s%s\n", nbuf, 2734 type == TYPE_A ? "\r" : ""); 2735 byte_count += strlen(nbuf) + 1; 2736 } 2737 } 2738 (void) closedir(dirp); 2739 } 2740 2741 if (dout == NULL) 2742 reply(550, "No files found."); 2743 else if (ferror(dout) != 0) 2744 perror_reply(550, "Data connection"); 2745 else 2746 reply(226, "Transfer complete."); 2747 2748 transflag = 0; 2749 if (dout != NULL) 2750 (void) fclose(dout); 2751 else { 2752 if (pdata >= 0) 2753 close(pdata); 2754 } 2755 data = -1; 2756 pdata = -1; 2757 out: 2758 if (freeglob) { 2759 freeglob = 0; 2760 globfree(&gl); 2761 } 2762 } 2763 2764 /*ARGSUSED*/ 2765 static void 2766 reapchild(int signo) 2767 { 2768 int save_errno = errno; 2769 int rval; 2770 2771 do { 2772 rval = waitpid(-1, NULL, WNOHANG); 2773 } while (rval > 0 || (rval == -1 && errno == EINTR)); 2774 errno = save_errno; 2775 } 2776 2777 void 2778 logxfer(char *name, off_t size, time_t start) 2779 { 2780 char buf[400 + MAXHOSTNAMELEN*4 + MAXPATHLEN*4]; 2781 char dir[MAXPATHLEN], path[MAXPATHLEN], rpath[MAXPATHLEN]; 2782 char vremotehost[MAXHOSTNAMELEN*4], vpath[MAXPATHLEN*4]; 2783 char *vpw; 2784 time_t now; 2785 int len; 2786 2787 if ((statfd >= 0) && (getcwd(dir, sizeof(dir)) != NULL)) { 2788 time(&now); 2789 2790 vpw = malloc(strlen(guest ? guestpw : pw->pw_name) * 4 + 1); 2791 if (vpw == NULL) 2792 return; 2793 2794 snprintf(path, sizeof(path), "%s/%s", dir, name); 2795 if (realpath(path, rpath) == NULL) 2796 strlcpy(rpath, path, sizeof(rpath)); 2797 strvis(vpath, rpath, VIS_SAFE|VIS_NOSLASH); 2798 2799 strvis(vremotehost, remotehost, VIS_SAFE|VIS_NOSLASH); 2800 strvis(vpw, guest? guestpw : pw->pw_name, VIS_SAFE|VIS_NOSLASH); 2801 2802 len = snprintf(buf, sizeof(buf), 2803 "%.24s %d %s %qd %s %c %s %c %c %s ftp %d %s %s\n", 2804 ctime(&now), now - start + (now == start), 2805 vremotehost, (long long)size, vpath, 2806 ((type == TYPE_A) ? 'a' : 'b'), "*" /* none yet */, 2807 'o', ((guest) ? 'a' : 'r'), 2808 vpw, 0 /* none yet */, 2809 ((guest) ? "*" : pw->pw_name), dhostname); 2810 free(vpw); 2811 2812 if (len >= sizeof(buf) || len == -1) { 2813 if ((len = strlen(buf)) == 0) 2814 return; /* should not happen */ 2815 buf[len - 1] = '\n'; 2816 } 2817 write(statfd, buf, len); 2818 } 2819 } 2820 2821 void 2822 set_slave_signals(void) 2823 { 2824 struct sigaction sa; 2825 2826 sigemptyset(&sa.sa_mask); 2827 sa.sa_flags = SA_RESTART; 2828 2829 sa.sa_handler = SIG_DFL; 2830 (void) sigaction(SIGCHLD, &sa, NULL); 2831 2832 sa.sa_handler = sigurg; 2833 sa.sa_flags = 0; /* don't restart syscalls for SIGURG */ 2834 (void) sigaction(SIGURG, &sa, NULL); 2835 2836 sigfillset(&sa.sa_mask); /* block all signals in handler */ 2837 sa.sa_flags = SA_RESTART; 2838 sa.sa_handler = sigquit; 2839 (void) sigaction(SIGHUP, &sa, NULL); 2840 (void) sigaction(SIGINT, &sa, NULL); 2841 (void) sigaction(SIGQUIT, &sa, NULL); 2842 (void) sigaction(SIGTERM, &sa, NULL); 2843 2844 sa.sa_handler = lostconn; 2845 (void) sigaction(SIGPIPE, &sa, NULL); 2846 2847 sa.sa_handler = toolong; 2848 (void) sigaction(SIGALRM, &sa, NULL); 2849 2850 #ifdef F_SETOWN 2851 if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1) 2852 syslog(LOG_ERR, "fcntl F_SETOWN: %m"); 2853 #endif 2854 } 2855 2856 #if defined(TCPWRAPPERS) 2857 static int 2858 check_host(struct sockaddr *sa) 2859 { 2860 struct sockaddr_in *sin; 2861 struct hostent *hp; 2862 char *addr; 2863 2864 if (sa->sa_family != AF_INET) 2865 return 1; /*XXX*/ 2866 2867 sin = (struct sockaddr_in *)sa; 2868 hp = gethostbyaddr((char *)&sin->sin_addr, 2869 sizeof(struct in_addr), AF_INET); 2870 addr = inet_ntoa(sin->sin_addr); 2871 if (hp) { 2872 if (!hosts_ctl("ftpd", hp->h_name, addr, STRING_UNKNOWN)) { 2873 syslog(LOG_NOTICE, "tcpwrappers rejected: %s [%s]", 2874 hp->h_name, addr); 2875 return (0); 2876 } 2877 } else { 2878 if (!hosts_ctl("ftpd", STRING_UNKNOWN, addr, STRING_UNKNOWN)) { 2879 syslog(LOG_NOTICE, "tcpwrappers rejected: [%s]", addr); 2880 return (0); 2881 } 2882 } 2883 return (1); 2884 } 2885 #endif /* TCPWRAPPERS */ 2886 2887 /* 2888 * Allocate space and return a copy of the specified dir. 2889 * If 'dir' begins with a tilde (~), expand it. 2890 */ 2891 char * 2892 copy_dir(char *dir, struct passwd *pw) 2893 { 2894 char *cp; 2895 char *newdir; 2896 char *user = NULL; 2897 2898 /* Nothing to expand */ 2899 if (dir[0] != '~') 2900 return (strdup(dir)); 2901 2902 /* "dir" is of form ~user/some/dir, lookup user. */ 2903 if (dir[1] != '/' && dir[1] != '\0') { 2904 if ((cp = strchr(dir + 1, '/')) == NULL) 2905 cp = dir + strlen(dir); 2906 if ((user = malloc((size_t)(cp - dir))) == NULL) 2907 return (NULL); 2908 strlcpy(user, dir + 1, (size_t)(cp - dir)); 2909 2910 /* Only do lookup if it is a different user. */ 2911 if (strcmp(user, pw->pw_name) != 0) { 2912 if ((pw = getpwnam(user)) == NULL) { 2913 /* No such user, interpret literally */ 2914 free(user); 2915 return(strdup(dir)); 2916 } 2917 } 2918 free(user); 2919 } 2920 2921 /* 2922 * If there is no directory separator (/) then it is just pw_dir. 2923 * Otherwise, replace ~foo with pw_dir. 2924 */ 2925 if ((cp = strchr(dir + 1, '/')) == NULL) { 2926 newdir = strdup(pw->pw_dir); 2927 } else { 2928 if (asprintf(&newdir, "%s%s", pw->pw_dir, cp) == -1) 2929 return (NULL); 2930 } 2931 2932 return(newdir); 2933 } 2934