libexec/ftpd/ftpd.c

   1 /*
   2  * Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #if 0
  35 #ifndef lint
  36 static char copyright[] =
  37 "@(#) Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994\n\
  38         The Regents of the University of California.  All rights reserved.\n";
  39 #endif /* not lint */
  40 #endif
  41
  42 #ifndef lint
  43 #if 0
  44 static char sccsid[] = "@(#)ftpd.c      8.4 (Berkeley) 4/16/94";
  45 #endif
  46 #endif /* not lint */
  47
  48 #include <sys/cdefs.h>
  49 __FBSDID("$FreeBSD$");
  50
  51 /*
  52  * FTP server.
  53  */
  54 #include <sys/param.h>
  55 #include <sys/ioctl.h>
  56 #include <sys/mman.h>
  57 #include <sys/socket.h>
  58 #include <sys/stat.h>
  59 #include <sys/time.h>
  60 #include <sys/wait.h>
  61
  62 #include <netinet/in.h>
  63 #include <netinet/in_systm.h>
  64 #include <netinet/ip.h>
  65 #include <netinet/tcp.h>
  66
  67 #define FTP_NAMES
  68 #include <arpa/ftp.h>
  69 #include <arpa/inet.h>
  70 #include <arpa/telnet.h>
  71
  72 #include <ctype.h>
  73 #include <dirent.h>
  74 #include <err.h>
  75 #include <errno.h>
  76 #include <fcntl.h>
  77 #include <glob.h>
  78 #include <limits.h>
  79 #include <netdb.h>
  80 #include <pwd.h>
  81 #include <grp.h>
  82 #include <opie.h>
  83 #include <signal.h>
  84 #include <stdint.h>
  85 #include <stdio.h>
  86 #include <stdlib.h>
  87 #include <string.h>
  88 #include <syslog.h>
  89 #include <time.h>
  90 #include <unistd.h>
  91 #include <libutil.h>
  92 #ifdef  LOGIN_CAP
  93 #include <login_cap.h>
  94 #endif
  95
  96 #ifdef USE_PAM
  97 #include <security/pam_appl.h>
  98 #endif
  99
 100 #include "pathnames.h"
 101 #include "extern.h"
 102
 103 #include <stdarg.h>
 104
 105 static char version[] = "Version 6.00LS";
 106 #undef main
 107
 108 union sockunion ctrl_addr;
 109 union sockunion data_source;
 110 union sockunion data_dest;
 111 union sockunion his_addr;
 112 union sockunion pasv_addr;
 113
 114 int     daemon_mode;
 115 int     data;
 116 int     dataport;
 117 int     hostinfo = 1;   /* print host-specific info in messages */
 118 int     logged_in;
 119 struct  passwd *pw;
 120 char    *homedir;
 121 int     ftpdebug;
 122 int     timeout = 900;    /* timeout after 15 minutes of inactivity */
 123 int     maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */
 124 int     logging;
 125 int     restricted_data_ports = 1;
 126 int     paranoid = 1;     /* be extra careful about security */
 127 int     anon_only = 0;    /* Only anonymous ftp allowed */
 128 int     assumeutf8 = 0;   /* Assume that server file names are in UTF-8 */
 129 int     guest;
 130 int     dochroot;
 131 char    *chrootdir;
 132 int     dowtmp = 1;
 133 int     stats;
 134 int     statfd = -1;
 135 int     type;
 136 int     form;
 137 int     stru;                   /* avoid C keyword */
 138 int     mode;
 139 int     usedefault = 1;         /* for data transfers */
 140 int     pdata = -1;             /* for passive mode */
 141 int     readonly = 0;           /* Server is in readonly mode.  */
 142 int     noepsv = 0;             /* EPSV command is disabled.    */
 143 int     noretr = 0;             /* RETR command is disabled.    */
 144 int     noguestretr = 0;        /* RETR command is disabled for anon users. */
 145 int     noguestmkd = 0;         /* MKD command is disabled for anon users. */
 146 int     noguestmod = 1;         /* anon users may not modify existing files. */
 147
 148 off_t   file_size;
 149 off_t   byte_count;
 150 #if !defined(CMASK) || CMASK == 0
 151 #undef CMASK
 152 #define CMASK 027
 153 #endif
 154 int     defumask = CMASK;               /* default umask value */
 155 char    tmpline[7];
 156 char    *hostname;
 157 int     epsvall = 0;
 158
 159 #ifdef VIRTUAL_HOSTING
 160 char    *ftpuser;
 161
 162 static struct ftphost {
 163         struct ftphost  *next;
 164         struct addrinfo *hostinfo;
 165         char            *hostname;
 166         char            *anonuser;
 167         char            *statfile;
 168         char            *welcome;
 169         char            *loginmsg;
 170 } *thishost, *firsthost;
 171
 172 #endif
 173 char    remotehost[NI_MAXHOST];
 174 char    *ident = NULL;
 175
 176 static char     ttyline[20];
 177 char            *tty = ttyline;         /* for klogin */
 178
 179 #ifdef USE_PAM
 180 static int      auth_pam(struct passwd**, const char*);
 181 pam_handle_t    *pamh = NULL;
 182 #endif
 183
 184 static struct opie      opiedata;
 185 static char             opieprompt[OPIE_CHALLENGE_MAX+1];
 186 static int              pwok;
 187
 188 char    *pid_file = NULL; /* means default location to pidfile(3) */
 189
 190 /*
 191  * Limit number of pathnames that glob can return.
 192  * A limit of 0 indicates the number of pathnames is unlimited.
 193  */
 194 #define MAXGLOBARGS     16384
 195 #
 196
 197 /*
 198  * Timeout intervals for retrying connections
 199  * to hosts that don't accept PORT cmds.  This
 200  * is a kludge, but given the problems with TCP...
 201  */
 202 #define SWAITMAX        90      /* wait at most 90 seconds */
 203 #define SWAITINT        5       /* interval between retries */
 204
 205 int     swaitmax = SWAITMAX;
 206 int     swaitint = SWAITINT;
 207
 208 #ifdef SETPROCTITLE
 209 #ifdef OLD_SETPROCTITLE
 210 char    **Argv = NULL;          /* pointer to argument vector */
 211 char    *LastArgv = NULL;       /* end of argv */
 212 #endif /* OLD_SETPROCTITLE */
 213 char    proctitle[LINE_MAX];    /* initial part of title */
 214 #endif /* SETPROCTITLE */
 215
 216 #define LOGCMD(cmd, file)               logcmd((cmd), (file), NULL, -1)
 217 #define LOGCMD2(cmd, file1, file2)      logcmd((cmd), (file1), (file2), -1)
 218 #define LOGBYTES(cmd, file, cnt)        logcmd((cmd), (file), NULL, (cnt))
 219
 220 static  volatile sig_atomic_t recvurg;
 221 static  int transflag;          /* NB: for debugging only */
 222
 223 #define STARTXFER       flagxfer(1)
 224 #define ENDXFER         flagxfer(0)
 225
 226 #define START_UNSAFE    maskurg(1)
 227 #define END_UNSAFE      maskurg(0)
 228
 229 /* It's OK to put an `else' clause after this macro. */
 230 #define CHECKOOB(action)                                                \
 231         if (recvurg) {                                                  \
 232                 recvurg = 0;                                            \
 233                 if (myoob()) {                                          \
 234                         ENDXFER;                                        \
 235                         action;                                         \
 236                 }                                                       \
 237         }
 238
 239 #ifdef VIRTUAL_HOSTING
 240 static void      inithosts(int);
 241 static void      selecthost(union sockunion *);
 242 #endif
 243 static void      ack(char *);
 244 static void      sigurg(int);
 245 static void      maskurg(int);
 246 static void      flagxfer(int);
 247 static int       myoob(void);
 248 static int       checkuser(char *, char *, int, char **);
 249 static FILE     *dataconn(char *, off_t, char *);
 250 static void      dolog(struct sockaddr *);
 251 static void      end_login(void);
 252 static FILE     *getdatasock(char *);
 253 static int       guniquefd(char *, char **);
 254 static void      lostconn(int);
 255 static void      sigquit(int);
 256 static int       receive_data(FILE *, FILE *);
 257 static int       send_data(FILE *, FILE *, size_t, off_t, int);
 258 static struct passwd *
 259                  sgetpwnam(char *);
 260 static char     *sgetsave(char *);
 261 static void      reapchild(int);
 262 static void      appendf(char **, char *, ...) __printflike(2, 3);
 263 static void      logcmd(char *, char *, char *, off_t);
 264 static void      logxfer(char *, off_t, time_t);
 265 static char     *doublequote(char *);
 266 static int      *socksetup(int, char *, const char *);
 267
 268 int
 269 main(int argc, char *argv[], char **envp)
 270 {
 271         socklen_t addrlen;
 272         int ch, on = 1, tos;
 273         char *cp, line[LINE_MAX];
 274         FILE *fd;
 275         char    *bindname = NULL;
 276         const char *bindport = "ftp";
 277         int     family = AF_UNSPEC;
 278         struct sigaction sa;
 279
 280         tzset();                /* in case no timezone database in ~ftp */
 281         sigemptyset(&sa.sa_mask);
 282         sa.sa_flags = SA_RESTART;
 283
 284 #ifdef OLD_SETPROCTITLE
 285         /*
 286          *  Save start and extent of argv for setproctitle.
 287          */
 288         Argv = argv;
 289         while (*envp)
 290                 envp++;
 291         LastArgv = envp[-1] + strlen(envp[-1]);
 292 #endif /* OLD_SETPROCTITLE */
 293
 294         /*
 295          * Prevent diagnostic messages from appearing on stderr.
 296          * We run as a daemon or from inetd; in both cases, there's
 297          * more reason in logging to syslog.
 298          */
 299         (void) freopen(_PATH_DEVNULL, "w", stderr);
 300         opterr = 0;
 301
 302         /*
 303          * LOG_NDELAY sets up the logging connection immediately,
 304          * necessary for anonymous ftp's that chroot and can't do it later.
 305          */
 306         openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP);
 307
 308         while ((ch = getopt(argc, argv,
 309                             "468a:AdDEhlmMoOp:P:rRSt:T:u:UvW")) != -1) {
 310                 switch (ch) {
 311                 case '4':
 312                         family = (family == AF_INET6) ? AF_UNSPEC : AF_INET;
 313                         break;
 314
 315                 case '6':
 316                         family = (family == AF_INET) ? AF_UNSPEC : AF_INET6;
 317                         break;
 318
 319                 case '8':
 320                         assumeutf8 = 1;
 321                         break;
 322
 323                 case 'a':
 324                         bindname = optarg;
 325                         break;
 326
 327                 case 'A':
 328                         anon_only = 1;
 329                         break;
 330
 331                 case 'd':
 332                         ftpdebug++;
 333                         break;
 334
 335                 case 'D':
 336                         daemon_mode++;
 337                         break;
 338
 339                 case 'E':
 340                         noepsv = 1;
 341                         break;
 342
 343                 case 'h':
 344                         hostinfo = 0;
 345                         break;
 346
 347                 case 'l':
 348                         logging++;      /* > 1 == extra logging */
 349                         break;
 350
 351                 case 'm':
 352                         noguestmod = 0;
 353                         break;
 354
 355                 case 'M':
 356                         noguestmkd = 1;
 357                         break;
 358
 359                 case 'o':
 360                         noretr = 1;
 361                         break;
 362
 363                 case 'O':
 364                         noguestretr = 1;
 365                         break;
 366
 367                 case 'p':
 368                         pid_file = optarg;
 369                         break;
 370
 371                 case 'P':
 372                         bindport = optarg;
 373                         break;
 374
 375                 case 'r':
 376                         readonly = 1;
 377                         break;
 378
 379                 case 'R':
 380                         paranoid = 0;
 381                         break;
 382
 383                 case 'S':
 384                         stats++;
 385                         break;
 386
 387                 case 't':
 388                         timeout = atoi(optarg);
 389                         if (maxtimeout < timeout)
 390                                 maxtimeout = timeout;
 391                         break;
 392
 393                 case 'T':
 394                         maxtimeout = atoi(optarg);
 395                         if (timeout > maxtimeout)
 396                                 timeout = maxtimeout;
 397                         break;
 398
 399                 case 'u':
 400                     {
 401                         long val = 0;
 402
 403                         val = strtol(optarg, &optarg, 8);
 404                         if (*optarg != '\0' || val < 0)
 405                                 syslog(LOG_WARNING, "bad value for -u");
 406                         else
 407                                 defumask = val;
 408                         break;
 409                     }
 410                 case 'U':
 411                         restricted_data_ports = 0;
 412                         break;
 413
 414                 case 'v':
 415                         ftpdebug++;
 416                         break;
 417
 418                 case 'W':
 419                         dowtmp = 0;
 420                         break;
 421
 422                 default:
 423                         syslog(LOG_WARNING, "unknown flag -%c ignored", optopt);
 424                         break;
 425                 }
 426         }
 427
 428         if (daemon_mode) {
 429                 int *ctl_sock, fd, maxfd = -1, nfds, i;
 430                 fd_set defreadfds, readfds;
 431                 pid_t pid;
 432                 struct pidfh *pfh;
 433
 434                 if ((pfh = pidfile_open(pid_file, 0600, &pid)) == NULL) {
 435                         if (errno == EEXIST) {
 436                                 syslog(LOG_ERR, "%s already running, pid %d",
 437                                        getprogname(), (int)pid);
 438                                 exit(1);
 439                         }
 440                         syslog(LOG_WARNING, "pidfile_open: %m");
 441                 }
 442
 443                 /*
 444                  * Detach from parent.
 445                  */
 446                 if (daemon(1, 1) < 0) {
 447                         syslog(LOG_ERR, "failed to become a daemon");
 448                         exit(1);
 449                 }
 450
 451                 if (pfh != NULL && pidfile_write(pfh) == -1)
 452                         syslog(LOG_WARNING, "pidfile_write: %m");
 453
 454                 sa.sa_handler = reapchild;
 455                 (void)sigaction(SIGCHLD, &sa, NULL);
 456
 457 #ifdef VIRTUAL_HOSTING
 458                 inithosts(family);
 459 #endif
 460
 461                 /*
 462                  * Open a socket, bind it to the FTP port, and start
 463                  * listening.
 464                  */
 465                 ctl_sock = socksetup(family, bindname, bindport);
 466                 if (ctl_sock == NULL)
 467                         exit(1);
 468
 469                 FD_ZERO(&defreadfds);
 470                 for (i = 1; i <= *ctl_sock; i++) {
 471                         FD_SET(ctl_sock[i], &defreadfds);
 472                         if (listen(ctl_sock[i], 32) < 0) {
 473                                 syslog(LOG_ERR, "control listen: %m");
 474                                 exit(1);
 475                         }
 476                         if (maxfd < ctl_sock[i])
 477                                 maxfd = ctl_sock[i];
 478                 }
 479
 480                 /*
 481                  * Loop forever accepting connection requests and forking off
 482                  * children to handle them.
 483                  */
 484                 while (1) {
 485                         FD_COPY(&defreadfds, &readfds);
 486                         nfds = select(maxfd + 1, &readfds, NULL, NULL, 0);
 487                         if (nfds <= 0) {
 488                                 if (nfds < 0 && errno != EINTR)
 489                                         syslog(LOG_WARNING, "select: %m");
 490                                 continue;
 491                         }
 492
 493                         pid = -1;
 494                         for (i = 1; i <= *ctl_sock; i++)
 495                                 if (FD_ISSET(ctl_sock[i], &readfds)) {
 496                                         addrlen = sizeof(his_addr);
 497                                         fd = accept(ctl_sock[i],
 498                                             (struct sockaddr *)&his_addr,
 499                                             &addrlen);
 500                                         if (fd == -1) {
 501                                                 syslog(LOG_WARNING,
 502                                                        "accept: %m");
 503                                                 continue;
 504                                         }
 505                                         switch (pid = fork()) {
 506                                         case 0:
 507                                                 /* child */
 508                                                 (void) dup2(fd, 0);
 509                                                 (void) dup2(fd, 1);
 510                                                 (void) close(fd);
 511                                                 for (i = 1; i <= *ctl_sock; i++)
 512                                                         close(ctl_sock[i]);
 513                                                 if (pfh != NULL)
 514                                                         pidfile_close(pfh);
 515                                                 goto gotchild;
 516                                         case -1:
 517                                                 syslog(LOG_WARNING, "fork: %m");
 518                                                 /* FALLTHROUGH */
 519                                         default:
 520                                                 close(fd);
 521                                         }
 522                                 }
 523                 }
 524         } else {
 525                 addrlen = sizeof(his_addr);
 526                 if (getpeername(0, (struct sockaddr *)&his_addr, &addrlen) < 0) {
 527                         syslog(LOG_ERR, "getpeername (%s): %m",argv[0]);
 528                         exit(1);
 529                 }
 530
 531 #ifdef VIRTUAL_HOSTING
 532                 if (his_addr.su_family == AF_INET6 &&
 533                     IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr))
 534                         family = AF_INET;
 535                 else
 536                         family = his_addr.su_family;
 537                 inithosts(family);
 538 #endif
 539         }
 540
 541 gotchild:
 542         sa.sa_handler = SIG_DFL;
 543         (void)sigaction(SIGCHLD, &sa, NULL);
 544
 545         sa.sa_handler = sigurg;
 546         sa.sa_flags = 0;                /* don't restart syscalls for SIGURG */
 547         (void)sigaction(SIGURG, &sa, NULL);
 548
 549         sigfillset(&sa.sa_mask);        /* block all signals in handler */
 550         sa.sa_flags = SA_RESTART;
 551         sa.sa_handler = sigquit;
 552         (void)sigaction(SIGHUP, &sa, NULL);
 553         (void)sigaction(SIGINT, &sa, NULL);
 554         (void)sigaction(SIGQUIT, &sa, NULL);
 555         (void)sigaction(SIGTERM, &sa, NULL);
 556
 557         sa.sa_handler = lostconn;
 558         (void)sigaction(SIGPIPE, &sa, NULL);
 559
 560         addrlen = sizeof(ctrl_addr);
 561         if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) {
 562                 syslog(LOG_ERR, "getsockname (%s): %m",argv[0]);
 563                 exit(1);
 564         }
 565         dataport = ntohs(ctrl_addr.su_port) - 1; /* as per RFC 959 */
 566 #ifdef VIRTUAL_HOSTING
 567         /* select our identity from virtual host table */
 568         selecthost(&ctrl_addr);
 569 #endif
 570 #ifdef IP_TOS
 571         if (ctrl_addr.su_family == AF_INET)
 572       {
 573         tos = IPTOS_LOWDELAY;
 574         if (setsockopt(0, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
 575                 syslog(LOG_WARNING, "control setsockopt (IP_TOS): %m");
 576       }
 577 #endif
 578         /*
 579          * Disable Nagle on the control channel so that we don't have to wait
 580          * for peer's ACK before issuing our next reply.
 581          */
 582         if (setsockopt(0, IPPROTO_TCP, TCP_NODELAY, &on, sizeof(on)) < 0)
 583                 syslog(LOG_WARNING, "control setsockopt (TCP_NODELAY): %m");
 584
 585         data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1);
 586
 587         /* set this here so klogin can use it... */
 588         (void)snprintf(ttyline, sizeof(ttyline), "ftp%d", getpid());
 589
 590         /* Try to handle urgent data inline */
 591 #ifdef SO_OOBINLINE
 592         if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, &on, sizeof(on)) < 0)
 593                 syslog(LOG_WARNING, "control setsockopt (SO_OOBINLINE): %m");
 594 #endif
 595
 596 #ifdef  F_SETOWN
 597         if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1)
 598                 syslog(LOG_ERR, "fcntl F_SETOWN: %m");
 599 #endif
 600         dolog((struct sockaddr *)&his_addr);
 601         /*
 602          * Set up default state
 603          */
 604         data = -1;
 605         type = TYPE_A;
 606         form = FORM_N;
 607         stru = STRU_F;
 608         mode = MODE_S;
 609         tmpline[0] = '\0';
 610
 611         /* If logins are disabled, print out the message. */
 612         if ((fd = fopen(_PATH_NOLOGIN,"r")) != NULL) {
 613                 while (fgets(line, sizeof(line), fd) != NULL) {
 614                         if ((cp = strchr(line, '\n')) != NULL)
 615                                 *cp = '\0';
 616                         lreply(530, "%s", line);
 617                 }
 618                 (void) fflush(stdout);
 619                 (void) fclose(fd);
 620                 reply(530, "System not available.");
 621                 exit(0);
 622         }
 623 #ifdef VIRTUAL_HOSTING
 624         fd = fopen(thishost->welcome, "r");
 625 #else
 626         fd = fopen(_PATH_FTPWELCOME, "r");
 627 #endif
 628         if (fd != NULL) {
 629                 while (fgets(line, sizeof(line), fd) != NULL) {
 630                         if ((cp = strchr(line, '\n')) != NULL)
 631                                 *cp = '\0';
 632                         lreply(220, "%s", line);
 633                 }
 634                 (void) fflush(stdout);
 635                 (void) fclose(fd);
 636                 /* reply(220,) must follow */
 637         }
 638 #ifndef VIRTUAL_HOSTING
 639         if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
 640                 fatalerror("Ran out of memory.");
 641         if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
 642                 hostname[0] = '\0';
 643         hostname[MAXHOSTNAMELEN - 1] = '\0';
 644 #endif
 645         if (hostinfo)
 646                 reply(220, "%s FTP server (%s) ready.", hostname, version);
 647         else
 648                 reply(220, "FTP server ready.");
 649         for (;;)
 650                 (void) yyparse();
 651         /* NOTREACHED */
 652 }
 653
 654 static void
 655 lostconn(int signo)
 656 {
 657
 658         if (ftpdebug)
 659                 syslog(LOG_DEBUG, "lost connection");
 660         dologout(1);
 661 }
 662
 663 static void
 664 sigquit(int signo)
 665 {
 666
 667         syslog(LOG_ERR, "got signal %d", signo);
 668         dologout(1);
 669 }
 670
 671 #ifdef VIRTUAL_HOSTING
 672 /*
 673  * read in virtual host tables (if they exist)
 674  */
 675
 676 static void
 677 inithosts(int family)
 678 {
 679         int insert;
 680         size_t len;
 681         FILE *fp;
 682         char *cp, *mp, *line;
 683         char *hostname;
 684         char *vhost, *anonuser, *statfile, *welcome, *loginmsg;
 685         struct ftphost *hrp, *lhrp;
 686         struct addrinfo hints, *res, *ai;
 687
 688         /*
 689          * Fill in the default host information
 690          */
 691         if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
 692                 fatalerror("Ran out of memory.");
 693         if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
 694                 hostname[0] = '\0';
 695         hostname[MAXHOSTNAMELEN - 1] = '\0';
 696         if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
 697                 fatalerror("Ran out of memory.");
 698         hrp->hostname = hostname;
 699         hrp->hostinfo = NULL;
 700
 701         memset(&hints, 0, sizeof(hints));
 702         hints.ai_flags = AI_PASSIVE;
 703         hints.ai_family = family;
 704         hints.ai_socktype = SOCK_STREAM;
 705         if (getaddrinfo(hrp->hostname, NULL, &hints, &res) == 0)
 706                 hrp->hostinfo = res;
 707         hrp->statfile = _PATH_FTPDSTATFILE;
 708         hrp->welcome  = _PATH_FTPWELCOME;
 709         hrp->loginmsg = _PATH_FTPLOGINMESG;
 710         hrp->anonuser = "ftp";
 711         hrp->next = NULL;
 712         thishost = firsthost = lhrp = hrp;
 713         if ((fp = fopen(_PATH_FTPHOSTS, "r")) != NULL) {
 714                 int addrsize, gothost;
 715                 void *addr;
 716                 struct hostent *hp;
 717
 718                 while ((line = fgetln(fp, &len)) != NULL) {
 719                         int     i, hp_error;
 720
 721                         /* skip comments */
 722                         if (line[0] == '#')
 723                                 continue;
 724                         if (line[len - 1] == '\n') {
 725                                 line[len - 1] = '\0';
 726                                 mp = NULL;
 727                         } else {
 728                                 if ((mp = malloc(len + 1)) == NULL)
 729                                         fatalerror("Ran out of memory.");
 730                                 memcpy(mp, line, len);
 731                                 mp[len] = '\0';
 732                                 line = mp;
 733                         }
 734                         cp = strtok(line, " \t");
 735                         /* skip empty lines */
 736                         if (cp == NULL)
 737                                 goto nextline;
 738                         vhost = cp;
 739
 740                         /* set defaults */
 741                         anonuser = "ftp";
 742                         statfile = _PATH_FTPDSTATFILE;
 743                         welcome  = _PATH_FTPWELCOME;
 744                         loginmsg = _PATH_FTPLOGINMESG;
 745
 746                         /*
 747                          * Preparse the line so we can use its info
 748                          * for all the addresses associated with
 749                          * the virtual host name.
 750                          * Field 0, the virtual host name, is special:
 751                          * it's already parsed off and will be strdup'ed
 752                          * later, after we know its canonical form.
 753                          */
 754                         for (i = 1; i < 5 && (cp = strtok(NULL, " \t")); i++)
 755                                 if (*cp != '-' && (cp = strdup(cp)))
 756                                         switch (i) {
 757                                         case 1: /* anon user permissions */
 758                                                 anonuser = cp;
 759                                                 break;
 760                                         case 2: /* statistics file */
 761                                                 statfile = cp;
 762                                                 break;
 763                                         case 3: /* welcome message */
 764                                                 welcome  = cp;
 765                                                 break;
 766                                         case 4: /* login message */
 767                                                 loginmsg = cp;
 768                                                 break;
 769                                         default: /* programming error */
 770                                                 abort();
 771                                                 /* NOTREACHED */
 772                                         }
 773
 774                         hints.ai_flags = AI_PASSIVE;
 775                         hints.ai_family = family;
 776                         hints.ai_socktype = SOCK_STREAM;
 777                         if (getaddrinfo(vhost, NULL, &hints, &res) != 0)
 778                                 goto nextline;
 779                         for (ai = res; ai != NULL && ai->ai_addr != NULL;
 780                              ai = ai->ai_next) {
 781
 782                         gothost = 0;
 783                         for (hrp = firsthost; hrp != NULL; hrp = hrp->next) {
 784                                 struct addrinfo *hi;
 785
 786                                 for (hi = hrp->hostinfo; hi != NULL;
 787                                      hi = hi->ai_next)
 788                                         if (hi->ai_addrlen == ai->ai_addrlen &&
 789                                             memcmp(hi->ai_addr,
 790                                                    ai->ai_addr,
 791                                                    ai->ai_addr->sa_len) == 0) {
 792                                                 gothost++;
 793                                                 break;
 794                                         }
 795                                 if (gothost)
 796                                         break;
 797                         }
 798                         if (hrp == NULL) {
 799                                 if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
 800                                         goto nextline;
 801                                 hrp->hostname = NULL;
 802                                 insert = 1;
 803                         } else {
 804                                 if (hrp->hostinfo && hrp->hostinfo != res)
 805                                         freeaddrinfo(hrp->hostinfo);
 806                                 insert = 0; /* host already in the chain */
 807                         }
 808                         hrp->hostinfo = res;
 809
 810                         /*
 811                          * determine hostname to use.
 812                          * force defined name if there is a valid alias
 813                          * otherwise fallback to primary hostname
 814                          */
 815                         /* XXX: getaddrinfo() can't do alias check */
 816                         switch(hrp->hostinfo->ai_family) {
 817                         case AF_INET:
 818                                 addr = &((struct sockaddr_in *)hrp->hostinfo->ai_addr)->sin_addr;
 819                                 addrsize = sizeof(struct in_addr);
 820                                 break;
 821                         case AF_INET6:
 822                                 addr = &((struct sockaddr_in6 *)hrp->hostinfo->ai_addr)->sin6_addr;
 823                                 addrsize = sizeof(struct in6_addr);
 824                                 break;
 825                         default:
 826                                 /* should not reach here */
 827                                 freeaddrinfo(hrp->hostinfo);
 828                                 if (insert)
 829                                         free(hrp); /*not in chain, can free*/
 830                                 else
 831                                         hrp->hostinfo = NULL; /*mark as blank*/
 832                                 goto nextline;
 833                                 /* NOTREACHED */
 834                         }
 835                         if ((hp = getipnodebyaddr(addr, addrsize,
 836                                                   hrp->hostinfo->ai_family,
 837                                                   &hp_error)) != NULL) {
 838                                 if (strcmp(vhost, hp->h_name) != 0) {
 839                                         if (hp->h_aliases == NULL)
 840                                                 vhost = hp->h_name;
 841                                         else {
 842                                                 i = 0;
 843                                                 while (hp->h_aliases[i] &&
 844                                                        strcmp(vhost, hp->h_aliases[i]) != 0)
 845                                                         ++i;
 846                                                 if (hp->h_aliases[i] == NULL)
 847                                                         vhost = hp->h_name;
 848                                         }
 849                                 }
 850                         }
 851                         if (hrp->hostname &&
 852                             strcmp(hrp->hostname, vhost) != 0) {
 853                                 free(hrp->hostname);
 854                                 hrp->hostname = NULL;
 855                         }
 856                         if (hrp->hostname == NULL &&
 857                             (hrp->hostname = strdup(vhost)) == NULL) {
 858                                 freeaddrinfo(hrp->hostinfo);
 859                                 hrp->hostinfo = NULL; /* mark as blank */
 860                                 if (hp)
 861                                         freehostent(hp);
 862                                 goto nextline;
 863                         }
 864                         hrp->anonuser = anonuser;
 865                         hrp->statfile = statfile;
 866                         hrp->welcome  = welcome;
 867                         hrp->loginmsg = loginmsg;
 868                         if (insert) {
 869                                 hrp->next  = NULL;
 870                                 lhrp->next = hrp;
 871                                 lhrp = hrp;
 872                         }
 873                         if (hp)
 874                                 freehostent(hp);
 875                       }
 876 nextline:
 877                         if (mp)
 878                                 free(mp);
 879                 }
 880                 (void) fclose(fp);
 881         }
 882 }
 883
 884 static void
 885 selecthost(union sockunion *su)
 886 {
 887         struct ftphost  *hrp;
 888         u_int16_t port;
 889 #ifdef INET6
 890         struct in6_addr *mapped_in6 = NULL;
 891 #endif
 892         struct addrinfo *hi;
 893
 894 #ifdef INET6
 895         /*
 896          * XXX IPv4 mapped IPv6 addr consideraton,
 897          * specified in rfc2373.
 898          */
 899         if (su->su_family == AF_INET6 &&
 900             IN6_IS_ADDR_V4MAPPED(&su->su_sin6.sin6_addr))
 901                 mapped_in6 = &su->su_sin6.sin6_addr;
 902 #endif
 903
 904         hrp = thishost = firsthost;     /* default */
 905         port = su->su_port;
 906         su->su_port = 0;
 907         while (hrp != NULL) {
 908             for (hi = hrp->hostinfo; hi != NULL; hi = hi->ai_next) {
 909                 if (memcmp(su, hi->ai_addr, hi->ai_addrlen) == 0) {
 910                         thishost = hrp;
 911                         goto found;
 912                 }
 913 #ifdef INET6
 914                 /* XXX IPv4 mapped IPv6 addr consideraton */
 915                 if (hi->ai_addr->sa_family == AF_INET && mapped_in6 != NULL &&
 916                     (memcmp(&mapped_in6->s6_addr[12],
 917                             &((struct sockaddr_in *)hi->ai_addr)->sin_addr,
 918                             sizeof(struct in_addr)) == 0)) {
 919                         thishost = hrp;
 920                         goto found;
 921                 }
 922 #endif
 923             }
 924             hrp = hrp->next;
 925         }
 926 found:
 927         su->su_port = port;
 928         /* setup static variables as appropriate */
 929         hostname = thishost->hostname;
 930         ftpuser = thishost->anonuser;
 931 }
 932 #endif
 933
 934 /*
 935  * Helper function for sgetpwnam().
 936  */
 937 static char *
 938 sgetsave(char *s)
 939 {
 940         char *new = malloc(strlen(s) + 1);
 941
 942         if (new == NULL) {
 943                 reply(421, "Ran out of memory.");
 944                 dologout(1);
 945                 /* NOTREACHED */
 946         }
 947         (void) strcpy(new, s);
 948         return (new);
 949 }
 950
 951 /*
 952  * Save the result of a getpwnam.  Used for USER command, since
 953  * the data returned must not be clobbered by any other command
 954  * (e.g., globbing).
 955  * NB: The data returned by sgetpwnam() will remain valid until
 956  * the next call to this function.  Its difference from getpwnam()
 957  * is that sgetpwnam() is known to be called from ftpd code only.
 958  */
 959 static struct passwd *
 960 sgetpwnam(char *name)
 961 {
 962         static struct passwd save;
 963         struct passwd *p;
 964
 965         if ((p = getpwnam(name)) == NULL)
 966                 return (p);
 967         if (save.pw_name) {
 968                 free(save.pw_name);
 969                 free(save.pw_passwd);
 970                 free(save.pw_gecos);
 971                 free(save.pw_dir);
 972                 free(save.pw_shell);
 973         }
 974         save = *p;
 975         save.pw_name = sgetsave(p->pw_name);
 976         save.pw_passwd = sgetsave(p->pw_passwd);
 977         save.pw_gecos = sgetsave(p->pw_gecos);
 978         save.pw_dir = sgetsave(p->pw_dir);
 979         save.pw_shell = sgetsave(p->pw_shell);
 980         return (&save);
 981 }
 982
 983 static int login_attempts;      /* number of failed login attempts */
 984 static int askpasswd;           /* had user command, ask for passwd */
 985 static char curname[MAXLOGNAME];        /* current USER name */
 986
 987 /*
 988  * USER command.
 989  * Sets global passwd pointer pw if named account exists and is acceptable;
 990  * sets askpasswd if a PASS command is expected.  If logged in previously,
 991  * need to reset state.  If name is "ftp" or "anonymous", the name is not in
 992  * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return.
 993  * If account doesn't exist, ask for passwd anyway.  Otherwise, check user
 994  * requesting login privileges.  Disallow anyone who does not have a standard
 995  * shell as returned by getusershell().  Disallow anyone mentioned in the file
 996  * _PATH_FTPUSERS to allow people such as root and uucp to be avoided.
 997  */
 998 void
 999 user(char *name)
1000 {
1001         char *cp, *shell;
1002
1003         if (logged_in) {
1004                 if (guest) {
1005                         reply(530, "Can't change user from guest login.");
1006                         return;
1007                 } else if (dochroot) {
1008                         reply(530, "Can't change user from chroot user.");
1009                         return;
1010                 }
1011                 end_login();
1012         }
1013
1014         guest = 0;
1015 #ifdef VIRTUAL_HOSTING
1016         pw = sgetpwnam(thishost->anonuser);
1017 #else
1018         pw = sgetpwnam("ftp");
1019 #endif
1020         if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) {
1021                 if (checkuser(_PATH_FTPUSERS, "ftp", 0, NULL) ||
1022                     checkuser(_PATH_FTPUSERS, "anonymous", 0, NULL))
1023                         reply(530, "User %s access denied.", name);
1024                 else if (pw != NULL) {
1025                         guest = 1;
1026                         askpasswd = 1;
1027                         reply(331,
1028                         "Guest login ok, send your email address as password.");
1029                 } else
1030                         reply(530, "User %s unknown.", name);
1031                 if (!askpasswd && logging)
1032                         syslog(LOG_NOTICE,
1033                             "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost);
1034                 return;
1035         }
1036         if (anon_only != 0) {
1037                 reply(530, "Sorry, only anonymous ftp allowed.");
1038                 return;
1039         }
1040
1041         if ((pw = sgetpwnam(name))) {
1042                 if ((shell = pw->pw_shell) == NULL || *shell == 0)
1043                         shell = _PATH_BSHELL;
1044                 setusershell();
1045                 while ((cp = getusershell()) != NULL)
1046                         if (strcmp(cp, shell) == 0)
1047                                 break;
1048                 endusershell();
1049
1050                 if (cp == NULL || checkuser(_PATH_FTPUSERS, name, 1, NULL)) {
1051                         reply(530, "User %s access denied.", name);
1052                         if (logging)
1053                                 syslog(LOG_NOTICE,
1054                                     "FTP LOGIN REFUSED FROM %s, %s",
1055                                     remotehost, name);
1056                         pw = NULL;
1057                         return;
1058                 }
1059         }
1060         if (logging)
1061                 strncpy(curname, name, sizeof(curname)-1);
1062
1063         pwok = 0;
1064 #ifdef USE_PAM
1065         /* XXX Kluge! The conversation mechanism needs to be fixed. */
1066 #endif
1067         if (opiechallenge(&opiedata, name, opieprompt) == 0) {
1068                 pwok = (pw != NULL) &&
1069                        opieaccessfile(remotehost) &&
1070                        opiealways(pw->pw_dir);
1071                 reply(331, "Response to %s %s for %s.",
1072                       opieprompt, pwok ? "requested" : "required", name);
1073         } else {
1074                 pwok = 1;
1075                 reply(331, "Password required for %s.", name);
1076         }
1077         askpasswd = 1;
1078         /*
1079          * Delay before reading passwd after first failed
1080          * attempt to slow down passwd-guessing programs.
1081          */
1082         if (login_attempts)
1083                 sleep(login_attempts);
1084 }
1085
1086 /*
1087  * Check if a user is in the file "fname",
1088  * return a pointer to a malloc'd string with the rest
1089  * of the matching line in "residue" if not NULL.
1090  */
1091 static int
1092 checkuser(char *fname, char *name, int pwset, char **residue)
1093 {
1094         FILE *fd;
1095         int found = 0;
1096         size_t len;
1097         char *line, *mp, *p;
1098
1099         if ((fd = fopen(fname, "r")) != NULL) {
1100                 while (!found && (line = fgetln(fd, &len)) != NULL) {
1101                         /* skip comments */
1102                         if (line[0] == '#')
1103                                 continue;
1104                         if (line[len - 1] == '\n') {
1105                                 line[len - 1] = '\0';
1106                                 mp = NULL;
1107                         } else {
1108                                 if ((mp = malloc(len + 1)) == NULL)
1109                                         fatalerror("Ran out of memory.");
1110                                 memcpy(mp, line, len);
1111                                 mp[len] = '\0';
1112                                 line = mp;
1113                         }
1114                         /* avoid possible leading and trailing whitespace */
1115                         p = strtok(line, " \t");
1116                         /* skip empty lines */
1117                         if (p == NULL)
1118                                 goto nextline;
1119                         /*
1120                          * if first chr is '@', check group membership
1121                          */
1122                         if (p[0] == '@') {
1123                                 int i = 0;
1124                                 struct group *grp;
1125
1126                                 if (p[1] == '\0') /* single @ matches anyone */
1127                                         found = 1;
1128                                 else {
1129                                         if ((grp = getgrnam(p+1)) == NULL)
1130                                                 goto nextline;
1131                                         /*
1132                                          * Check user's default group
1133                                          */
1134                                         if (pwset && grp->gr_gid == pw->pw_gid)
1135                                                 found = 1;
1136                                         /*
1137                                          * Check supplementary groups
1138                                          */
1139                                         while (!found && grp->gr_mem[i])
1140                                                 found = strcmp(name,
1141                                                         grp->gr_mem[i++])
1142                                                         == 0;
1143                                 }
1144                         }
1145                         /*
1146                          * Otherwise, just check for username match
1147                          */
1148                         else
1149                                 found = strcmp(p, name) == 0;
1150                         /*
1151                          * Save the rest of line to "residue" if matched
1152                          */
1153                         if (found && residue) {
1154                                 if ((p = strtok(NULL, "")) != NULL)
1155                                         p += strspn(p, " \t");
1156                                 if (p && *p) {
1157                                         if ((*residue = strdup(p)) == NULL)
1158                                                 fatalerror("Ran out of memory.");
1159                                 } else
1160                                         *residue = NULL;
1161                         }
1162 nextline:
1163                         if (mp)
1164                                 free(mp);
1165                 }
1166                 (void) fclose(fd);
1167         }
1168         return (found);
1169 }
1170
1171 /*
1172  * Terminate login as previous user, if any, resetting state;
1173  * used when USER command is given or login fails.
1174  */
1175 static void
1176 end_login(void)
1177 {
1178 #ifdef USE_PAM
1179         int e;
1180 #endif
1181
1182         (void) seteuid(0);
1183         if (logged_in && dowtmp)
1184                 ftpd_logwtmp(ttyline, "", NULL);
1185         pw = NULL;
1186 #ifdef  LOGIN_CAP
1187         setusercontext(NULL, getpwuid(0), 0,
1188                        LOGIN_SETPRIORITY|LOGIN_SETRESOURCES|LOGIN_SETUMASK|
1189                        LOGIN_SETMAC);
1190 #endif
1191 #ifdef USE_PAM
1192         if (pamh) {
1193                 if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS)
1194                         syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1195                 if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS)
1196                         syslog(LOG_ERR, "pam_close_session: %s", pam_strerror(pamh, e));
1197                 if ((e = pam_end(pamh, e)) != PAM_SUCCESS)
1198                         syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1199                 pamh = NULL;
1200         }
1201 #endif
1202         logged_in = 0;
1203         guest = 0;
1204         dochroot = 0;
1205 }
1206
1207 #ifdef USE_PAM
1208
1209 /*
1210  * the following code is stolen from imap-uw PAM authentication module and
1211  * login.c
1212  */
1213 #define COPY_STRING(s) (s ? strdup(s) : NULL)
1214
1215 struct cred_t {
1216         const char *uname;              /* user name */
1217         const char *pass;               /* password */
1218 };
1219 typedef struct cred_t cred_t;
1220
1221 static int
1222 auth_conv(int num_msg, const struct pam_message **msg,
1223           struct pam_response **resp, void *appdata)
1224 {
1225         int i;
1226         cred_t *cred = (cred_t *) appdata;
1227         struct pam_response *reply;
1228
1229         reply = calloc(num_msg, sizeof *reply);
1230         if (reply == NULL)
1231                 return PAM_BUF_ERR;
1232
1233         for (i = 0; i < num_msg; i++) {
1234                 switch (msg[i]->msg_style) {
1235                 case PAM_PROMPT_ECHO_ON:        /* assume want user name */
1236                         reply[i].resp_retcode = PAM_SUCCESS;
1237                         reply[i].resp = COPY_STRING(cred->uname);
1238                         /* PAM frees resp. */
1239                         break;
1240                 case PAM_PROMPT_ECHO_OFF:       /* assume want password */
1241                         reply[i].resp_retcode = PAM_SUCCESS;
1242                         reply[i].resp = COPY_STRING(cred->pass);
1243                         /* PAM frees resp. */
1244                         break;
1245                 case PAM_TEXT_INFO:
1246                 case PAM_ERROR_MSG:
1247                         reply[i].resp_retcode = PAM_SUCCESS;
1248                         reply[i].resp = NULL;
1249                         break;
1250                 default:                        /* unknown message style */
1251                         free(reply);
1252                         return PAM_CONV_ERR;
1253                 }
1254         }
1255
1256         *resp = reply;
1257         return PAM_SUCCESS;
1258 }
1259
1260 /*
1261  * Attempt to authenticate the user using PAM.  Returns 0 if the user is
1262  * authenticated, or 1 if not authenticated.  If some sort of PAM system
1263  * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
1264  * function returns -1.  This can be used as an indication that we should
1265  * fall back to a different authentication mechanism.
1266  */
1267 static int
1268 auth_pam(struct passwd **ppw, const char *pass)
1269 {
1270         const char *tmpl_user;
1271         const void *item;
1272         int rval;
1273         int e;
1274         cred_t auth_cred = { (*ppw)->pw_name, pass };
1275         struct pam_conv conv = { &auth_conv, &auth_cred };
1276
1277         e = pam_start("ftpd", (*ppw)->pw_name, &conv, &pamh);
1278         if (e != PAM_SUCCESS) {
1279                 /*
1280                  * In OpenPAM, it's OK to pass NULL to pam_strerror()
1281                  * if context creation has failed in the first place.
1282                  */
1283                 syslog(LOG_ERR, "pam_start: %s", pam_strerror(NULL, e));
1284                 return -1;
1285         }
1286
1287         e = pam_set_item(pamh, PAM_RHOST, remotehost);
1288         if (e != PAM_SUCCESS) {
1289                 syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
1290                         pam_strerror(pamh, e));
1291                 if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1292                         syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1293                 }
1294                 pamh = NULL;
1295                 return -1;
1296         }
1297
1298         e = pam_authenticate(pamh, 0);
1299         switch (e) {
1300         case PAM_SUCCESS:
1301                 /*
1302                  * With PAM we support the concept of a "template"
1303                  * user.  The user enters a login name which is
1304                  * authenticated by PAM, usually via a remote service
1305                  * such as RADIUS or TACACS+.  If authentication
1306                  * succeeds, a different but related "template" name
1307                  * is used for setting the credentials, shell, and
1308                  * home directory.  The name the user enters need only
1309                  * exist on the remote authentication server, but the
1310                  * template name must be present in the local password
1311                  * database.
1312                  *
1313                  * This is supported by two various mechanisms in the
1314                  * individual modules.  However, from the application's
1315                  * point of view, the template user is always passed
1316                  * back as a changed value of the PAM_USER item.
1317                  */
1318                 if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
1319                     PAM_SUCCESS) {
1320                         tmpl_user = (const char *) item;
1321                         if (strcmp((*ppw)->pw_name, tmpl_user) != 0)
1322                                 *ppw = getpwnam(tmpl_user);
1323                 } else
1324                         syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
1325                             pam_strerror(pamh, e));
1326                 rval = 0;
1327                 break;
1328
1329         case PAM_AUTH_ERR:
1330         case PAM_USER_UNKNOWN:
1331         case PAM_MAXTRIES:
1332                 rval = 1;
1333                 break;
1334
1335         default:
1336                 syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
1337                 rval = -1;
1338                 break;
1339         }
1340
1341         if (rval == 0) {
1342                 e = pam_acct_mgmt(pamh, 0);
1343                 if (e != PAM_SUCCESS) {
1344                         syslog(LOG_ERR, "pam_acct_mgmt: %s",
1345                                                 pam_strerror(pamh, e));
1346                         rval = 1;
1347                 }
1348         }
1349
1350         if (rval != 0) {
1351                 if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1352                         syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1353                 }
1354                 pamh = NULL;
1355         }
1356         return rval;
1357 }
1358
1359 #endif /* USE_PAM */
1360
1361 void
1362 pass(char *passwd)
1363 {
1364         int rval;
1365         FILE *fd;
1366 #ifdef  LOGIN_CAP
1367         login_cap_t *lc = NULL;
1368 #endif
1369 #ifdef USE_PAM
1370         int e;
1371 #endif
1372         char *residue = NULL;
1373         char *xpasswd;
1374
1375         if (logged_in || askpasswd == 0) {
1376                 reply(503, "Login with USER first.");
1377                 return;
1378         }
1379         askpasswd = 0;
1380         if (!guest) {           /* "ftp" is only account allowed no password */
1381                 if (pw == NULL) {
1382                         rval = 1;       /* failure below */
1383                         goto skip;
1384                 }
1385 #ifdef USE_PAM
1386                 rval = auth_pam(&pw, passwd);
1387                 if (rval >= 0) {
1388                         opieunlock();
1389                         goto skip;
1390                 }
1391 #endif
1392                 if (opieverify(&opiedata, passwd) == 0)
1393                         xpasswd = pw->pw_passwd;
1394                 else if (pwok) {
1395                         xpasswd = crypt(passwd, pw->pw_passwd);
1396                         if (passwd[0] == '\0' && pw->pw_passwd[0] != '\0')
1397                                 xpasswd = ":";
1398                 } else {
1399                         rval = 1;
1400                         goto skip;
1401                 }
1402                 rval = strcmp(pw->pw_passwd, xpasswd);
1403                 if (pw->pw_expire && time(NULL) >= pw->pw_expire)
1404                         rval = 1;       /* failure */
1405 skip:
1406                 /*
1407                  * If rval == 1, the user failed the authentication check
1408                  * above.  If rval == 0, either PAM or local authentication
1409                  * succeeded.
1410                  */
1411                 if (rval) {
1412                         reply(530, "Login incorrect.");
1413                         if (logging) {
1414                                 syslog(LOG_NOTICE,
1415                                     "FTP LOGIN FAILED FROM %s",
1416                                     remotehost);
1417                                 syslog(LOG_AUTHPRIV | LOG_NOTICE,
1418                                     "FTP LOGIN FAILED FROM %s, %s",
1419                                     remotehost, curname);
1420                         }
1421                         pw = NULL;
1422                         if (login_attempts++ >= 5) {
1423                                 syslog(LOG_NOTICE,
1424                                     "repeated login failures from %s",
1425                                     remotehost);
1426                                 exit(0);
1427                         }
1428                         return;
1429                 }
1430         }
1431         login_attempts = 0;             /* this time successful */
1432         if (setegid(pw->pw_gid) < 0) {
1433                 reply(550, "Can't set gid.");
1434                 return;
1435         }
1436         /* May be overridden by login.conf */
1437         (void) umask(defumask);
1438 #ifdef  LOGIN_CAP
1439         if ((lc = login_getpwclass(pw)) != NULL) {
1440                 char    remote_ip[NI_MAXHOST];
1441
1442                 if (getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
1443                         remote_ip, sizeof(remote_ip) - 1, NULL, 0,
1444                         NI_NUMERICHOST))
1445                                 *remote_ip = 0;
1446                 remote_ip[sizeof(remote_ip) - 1] = 0;
1447                 if (!auth_hostok(lc, remotehost, remote_ip)) {
1448                         syslog(LOG_INFO|LOG_AUTH,
1449                             "FTP LOGIN FAILED (HOST) as %s: permission denied.",
1450                             pw->pw_name);
1451                         reply(530, "Permission denied.");
1452                         pw = NULL;
1453                         return;
1454                 }
1455                 if (!auth_timeok(lc, time(NULL))) {
1456                         reply(530, "Login not available right now.");
1457                         pw = NULL;
1458                         return;
1459                 }
1460         }
1461         setusercontext(lc, pw, 0,
1462                 LOGIN_SETLOGIN|LOGIN_SETGROUP|LOGIN_SETPRIORITY|
1463                 LOGIN_SETRESOURCES|LOGIN_SETUMASK|LOGIN_SETMAC);
1464 #else
1465         setlogin(pw->pw_name);
1466         (void) initgroups(pw->pw_name, pw->pw_gid);
1467 #endif
1468
1469 #ifdef USE_PAM
1470         if (pamh) {
1471                 if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
1472                         syslog(LOG_ERR, "pam_open_session: %s", pam_strerror(pamh, e));
1473                 } else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED)) != PAM_SUCCESS) {
1474                         syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1475                 }
1476         }
1477 #endif
1478
1479         /* open wtmp before chroot */
1480         if (dowtmp)
1481                 ftpd_logwtmp(ttyline, pw->pw_name,
1482                     (struct sockaddr *)&his_addr);
1483         logged_in = 1;
1484
1485         if (guest && stats && statfd < 0)
1486 #ifdef VIRTUAL_HOSTING
1487                 statfd = open(thishost->statfile, O_WRONLY|O_APPEND);
1488 #else
1489                 statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND);
1490 #endif
1491                 if (statfd < 0)
1492                         stats = 0;
1493
1494         dochroot =
1495                 checkuser(_PATH_FTPCHROOT, pw->pw_name, 1, &residue)
1496 #ifdef  LOGIN_CAP       /* Allow login.conf configuration as well */
1497                 || login_getcapbool(lc, "ftp-chroot", 0)
1498 #endif
1499         ;
1500         chrootdir = NULL;
1501         /*
1502          * For a chrooted local user,
1503          * a) see whether ftpchroot(5) specifies a chroot directory,
1504          * b) extract the directory pathname from the line,
1505          * c) expand it to the absolute pathname if necessary.
1506          */
1507         if (dochroot && residue &&
1508             (chrootdir = strtok(residue, " \t")) != NULL) {
1509                 if (chrootdir[0] != '/')
1510                         asprintf(&chrootdir, "%s/%s", pw->pw_dir, chrootdir);
1511                 else
1512                         chrootdir = strdup(chrootdir); /* make it permanent */
1513                 if (chrootdir == NULL)
1514                         fatalerror("Ran out of memory.");
1515         }
1516         if (guest || dochroot) {
1517                 /*
1518                  * If no chroot directory set yet, use the login directory.
1519                  * Copy it so it can be modified while pw->pw_dir stays intact.
1520                  */
1521                 if (chrootdir == NULL &&
1522                     (chrootdir = strdup(pw->pw_dir)) == NULL)
1523                         fatalerror("Ran out of memory.");
1524                 /*
1525                  * Check for the "/chroot/./home" syntax,
1526                  * separate the chroot and home directory pathnames.
1527                  */
1528                 if ((homedir = strstr(chrootdir, "/./")) != NULL) {
1529                         *(homedir++) = '\0';    /* wipe '/' */
1530                         homedir++;              /* skip '.' */
1531                 } else {
1532                         /*
1533                          * We MUST do a chdir() after the chroot. Otherwise
1534                          * the old current directory will be accessible as "."
1535                          * outside the new root!
1536                          */
1537                         homedir = "/";
1538                 }
1539                 /*
1540                  * Finally, do chroot()
1541                  */
1542                 if (chroot(chrootdir) < 0) {
1543                         reply(550, "Can't change root.");
1544                         goto bad;
1545                 }
1546         } else  /* real user w/o chroot */
1547                 homedir = pw->pw_dir;
1548         /*
1549          * Set euid *before* doing chdir() so
1550          * a) the user won't be carried to a directory that he couldn't reach
1551          *    on his own due to no permission to upper path components,
1552          * b) NFS mounted homedirs w/restrictive permissions will be accessible
1553          *    (uid 0 has no root power over NFS if not mapped explicitly.)
1554          */
1555         if (seteuid(pw->pw_uid) < 0) {
1556                 reply(550, "Can't set uid.");
1557                 goto bad;
1558         }
1559         if (chdir(homedir) < 0) {
1560                 if (guest || dochroot) {
1561                         reply(550, "Can't change to base directory.");
1562                         goto bad;
1563                 } else {
1564                         if (chdir("/") < 0) {
1565                                 reply(550, "Root is inaccessible.");
1566                                 goto bad;
1567                         }
1568                         lreply(230, "No directory! Logging in with home=/.");
1569                 }
1570         }
1571
1572         /*
1573          * Display a login message, if it exists.
1574          * N.B. reply(230,) must follow the message.
1575          */
1576 #ifdef VIRTUAL_HOSTING
1577         fd = fopen(thishost->loginmsg, "r");
1578 #else
1579         fd = fopen(_PATH_FTPLOGINMESG, "r");
1580 #endif
1581         if (fd != NULL) {
1582                 char *cp, line[LINE_MAX];
1583
1584                 while (fgets(line, sizeof(line), fd) != NULL) {
1585                         if ((cp = strchr(line, '\n')) != NULL)
1586                                 *cp = '\0';
1587                         lreply(230, "%s", line);
1588                 }
1589                 (void) fflush(stdout);
1590                 (void) fclose(fd);
1591         }
1592         if (guest) {
1593                 if (ident != NULL)
1594                         free(ident);
1595                 ident = strdup(passwd);
1596                 if (ident == NULL)
1597                         fatalerror("Ran out of memory.");
1598
1599                 reply(230, "Guest login ok, access restrictions apply.");
1600 #ifdef SETPROCTITLE
1601 #ifdef VIRTUAL_HOSTING
1602                 if (thishost != firsthost)
1603                         snprintf(proctitle, sizeof(proctitle),
1604                                  "%s: anonymous(%s)/%s", remotehost, hostname,
1605                                  passwd);
1606                 else
1607 #endif
1608                         snprintf(proctitle, sizeof(proctitle),
1609                                  "%s: anonymous/%s", remotehost, passwd);
1610                 setproctitle("%s", proctitle);
1611 #endif /* SETPROCTITLE */
1612                 if (logging)
1613                         syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s",
1614                             remotehost, passwd);
1615         } else {
1616                 if (dochroot)
1617                         reply(230, "User %s logged in, "
1618                                    "access restrictions apply.", pw->pw_name);
1619                 else
1620                         reply(230, "User %s logged in.", pw->pw_name);
1621
1622 #ifdef SETPROCTITLE
1623                 snprintf(proctitle, sizeof(proctitle),
1624                          "%s: user/%s", remotehost, pw->pw_name);
1625                 setproctitle("%s", proctitle);
1626 #endif /* SETPROCTITLE */
1627                 if (logging)
1628                         syslog(LOG_INFO, "FTP LOGIN FROM %s as %s",
1629                             remotehost, pw->pw_name);
1630         }
1631         if (logging && (guest || dochroot))
1632                 syslog(LOG_INFO, "session root changed to %s", chrootdir);
1633 #ifdef  LOGIN_CAP
1634         login_close(lc);
1635 #endif
1636         if (residue)
1637                 free(residue);
1638         return;
1639 bad:
1640         /* Forget all about it... */
1641 #ifdef  LOGIN_CAP
1642         login_close(lc);
1643 #endif
1644         if (residue)
1645                 free(residue);
1646         end_login();
1647 }
1648
1649 void
1650 retrieve(char *cmd, char *name)
1651 {
1652         FILE *fin, *dout;
1653         struct stat st;
1654         int (*closefunc)(FILE *);
1655         time_t start;
1656
1657         if (cmd == 0) {
1658                 fin = fopen(name, "r"), closefunc = fclose;
1659                 st.st_size = 0;
1660         } else {
1661                 char line[BUFSIZ];
1662
1663                 (void) snprintf(line, sizeof(line), cmd, name), name = line;
1664                 fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose;
1665                 st.st_size = -1;
1666                 st.st_blksize = BUFSIZ;
1667         }
1668         if (fin == NULL) {
1669                 if (errno != 0) {
1670                         perror_reply(550, name);
1671                         if (cmd == 0) {
1672                                 LOGCMD("get", name);
1673                         }
1674                 }
1675                 return;
1676         }
1677         byte_count = -1;
1678         if (cmd == 0) {
1679                 if (fstat(fileno(fin), &st) < 0) {
1680                         perror_reply(550, name);
1681                         goto done;
1682                 }
1683                 if (!S_ISREG(st.st_mode)) {
1684                         /*
1685                          * Never sending a raw directory is a workaround
1686                          * for buggy clients that will attempt to RETR
1687                          * a directory before listing it, e.g., Mozilla.
1688                          * Preventing a guest from getting irregular files
1689                          * is a simple security measure.
1690                          */
1691                         if (S_ISDIR(st.st_mode) || guest) {
1692                                 reply(550, "%s: not a plain file.", name);
1693                                 goto done;
1694                         }
1695                         st.st_size = -1;
1696                         /* st.st_blksize is set for all descriptor types */
1697                 }
1698         }
1699         if (restart_point) {
1700                 if (type == TYPE_A) {
1701                         off_t i, n;
1702                         int c;
1703
1704                         n = restart_point;
1705                         i = 0;
1706                         while (i++ < n) {
1707                                 if ((c=getc(fin)) == EOF) {
1708                                         perror_reply(550, name);
1709                                         goto done;
1710                                 }
1711                                 if (c == '\n')
1712                                         i++;
1713                         }
1714                 } else if (lseek(fileno(fin), restart_point, L_SET) < 0) {
1715                         perror_reply(550, name);
1716                         goto done;
1717                 }
1718         }
1719         dout = dataconn(name, st.st_size, "w");
1720         if (dout == NULL)
1721                 goto done;
1722         time(&start);
1723         send_data(fin, dout, st.st_blksize, st.st_size,
1724                   restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode));
1725         if (cmd == 0 && guest && stats && byte_count > 0)
1726                 logxfer(name, byte_count, start);
1727         (void) fclose(dout);
1728         data = -1;
1729         pdata = -1;
1730 done:
1731         if (cmd == 0)
1732                 LOGBYTES("get", name, byte_count);
1733         (*closefunc)(fin);
1734 }
1735
1736 void
1737 store(char *name, char *mode, int unique)
1738 {
1739         int fd;
1740         FILE *fout, *din;
1741         int (*closefunc)(FILE *);
1742
1743         if (*mode == 'a') {             /* APPE */
1744                 if (unique) {
1745                         /* Programming error */
1746                         syslog(LOG_ERR, "Internal: unique flag to APPE");
1747                         unique = 0;
1748                 }
1749                 if (guest && noguestmod) {
1750                         reply(550, "Appending to existing file denied.");
1751                         goto err;
1752                 }
1753                 restart_point = 0;      /* not affected by preceding REST */
1754         }
1755         if (unique)                     /* STOU overrides REST */
1756                 restart_point = 0;
1757         if (guest && noguestmod) {
1758                 if (restart_point) {    /* guest STOR w/REST */
1759                         reply(550, "Modifying existing file denied.");
1760                         goto err;
1761                 } else                  /* treat guest STOR as STOU */
1762                         unique = 1;
1763         }
1764
1765         if (restart_point)
1766                 mode = "r+";    /* so ASCII manual seek can work */
1767         if (unique) {
1768                 if ((fd = guniquefd(name, &name)) < 0)
1769                         goto err;
1770                 fout = fdopen(fd, mode);
1771         } else
1772                 fout = fopen(name, mode);
1773         closefunc = fclose;
1774         if (fout == NULL) {
1775                 perror_reply(553, name);
1776                 goto err;
1777         }
1778         byte_count = -1;
1779         if (restart_point) {
1780                 if (type == TYPE_A) {
1781                         off_t i, n;
1782                         int c;
1783
1784                         n = restart_point;
1785                         i = 0;
1786                         while (i++ < n) {
1787                                 if ((c=getc(fout)) == EOF) {
1788                                         perror_reply(550, name);
1789                                         goto done;
1790                                 }
1791                                 if (c == '\n')
1792                                         i++;
1793                         }
1794                         /*
1795                          * We must do this seek to "current" position
1796                          * because we are changing from reading to
1797                          * writing.
1798                          */
1799                         if (fseeko(fout, 0, SEEK_CUR) < 0) {
1800                                 perror_reply(550, name);
1801                                 goto done;
1802                         }
1803                 } else if (lseek(fileno(fout), restart_point, L_SET) < 0) {
1804                         perror_reply(550, name);
1805                         goto done;
1806                 }
1807         }
1808         din = dataconn(name, -1, "r");
1809         if (din == NULL)
1810                 goto done;
1811         if (receive_data(din, fout) == 0) {
1812                 if (unique)
1813                         reply(226, "Transfer complete (unique file name:%s).",
1814                             name);
1815                 else
1816                         reply(226, "Transfer complete.");
1817         }
1818         (void) fclose(din);
1819         data = -1;
1820         pdata = -1;
1821 done:
1822         LOGBYTES(*mode == 'a' ? "append" : "put", name, byte_count);
1823         (*closefunc)(fout);
1824         return;
1825 err:
1826         LOGCMD(*mode == 'a' ? "append" : "put" , name);
1827         return;
1828 }
1829
1830 static FILE *
1831 getdatasock(char *mode)
1832 {
1833         int on = 1, s, t, tries;
1834
1835         if (data >= 0)
1836                 return (fdopen(data, mode));
1837
1838         s = socket(data_dest.su_family, SOCK_STREAM, 0);
1839         if (s < 0)
1840                 goto bad;
1841         if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
1842                 syslog(LOG_WARNING, "data setsockopt (SO_REUSEADDR): %m");
1843         /* anchor socket to avoid multi-homing problems */
1844         data_source = ctrl_addr;
1845         data_source.su_port = htons(dataport);
1846         (void) seteuid(0);
1847         for (tries = 1; ; tries++) {
1848                 /*
1849                  * We should loop here since it's possible that
1850                  * another ftpd instance has passed this point and is
1851                  * trying to open a data connection in active mode now.
1852                  * Until the other connection is opened, we'll be getting
1853                  * EADDRINUSE because no SOCK_STREAM sockets in the system
1854                  * can share both local and remote addresses, localIP:20
1855                  * and *:* in this case.
1856                  */
1857                 if (bind(s, (struct sockaddr *)&data_source,
1858                     data_source.su_len) >= 0)
1859                         break;
1860                 if (errno != EADDRINUSE || tries > 10)
1861                         goto bad;
1862                 sleep(tries);
1863         }
1864         (void) seteuid(pw->pw_uid);
1865 #ifdef IP_TOS
1866         if (data_source.su_family == AF_INET)
1867       {
1868         on = IPTOS_THROUGHPUT;
1869         if (setsockopt(s, IPPROTO_IP, IP_TOS, &on, sizeof(int)) < 0)
1870                 syslog(LOG_WARNING, "data setsockopt (IP_TOS): %m");
1871       }
1872 #endif
1873 #ifdef TCP_NOPUSH
1874         /*
1875          * Turn off push flag to keep sender TCP from sending short packets
1876          * at the boundaries of each write().
1877          */
1878         on = 1;
1879         if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, &on, sizeof on) < 0)
1880                 syslog(LOG_WARNING, "data setsockopt (TCP_NOPUSH): %m");
1881 #endif
1882         return (fdopen(s, mode));
1883 bad:
1884         /* Return the real value of errno (close may change it) */
1885         t = errno;
1886         (void) seteuid(pw->pw_uid);
1887         (void) close(s);
1888         errno = t;
1889         return (NULL);
1890 }
1891
1892 static FILE *
1893 dataconn(char *name, off_t size, char *mode)
1894 {
1895         char sizebuf[32];
1896         FILE *file;
1897         int retry = 0, tos, conerrno;
1898
1899         file_size = size;
1900         byte_count = 0;
1901         if (size != -1)
1902                 (void) snprintf(sizebuf, sizeof(sizebuf),
1903                                 " (%jd bytes)", (intmax_t)size);
1904         else
1905                 *sizebuf = '\0';
1906         if (pdata >= 0) {
1907                 union sockunion from;
1908                 socklen_t fromlen = ctrl_addr.su_len;
1909                 int flags, s;
1910                 struct timeval timeout;
1911                 fd_set set;
1912
1913                 FD_ZERO(&set);
1914                 FD_SET(pdata, &set);
1915
1916                 timeout.tv_usec = 0;
1917                 timeout.tv_sec = 120;
1918
1919                 /*
1920                  * Granted a socket is in the blocking I/O mode,
1921                  * accept() will block after a successful select()
1922                  * if the selected connection dies in between.
1923                  * Therefore set the non-blocking I/O flag here.
1924                  */
1925                 if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1926                     fcntl(pdata, F_SETFL, flags | O_NONBLOCK) == -1)
1927                         goto pdata_err;
1928                 if (select(pdata+1, &set, NULL, NULL, &timeout) <= 0 ||
1929                     (s = accept(pdata, (struct sockaddr *) &from, &fromlen)) < 0)
1930                         goto pdata_err;
1931                 (void) close(pdata);
1932                 pdata = s;
1933                 /*
1934                  * Unset the inherited non-blocking I/O flag
1935                  * on the child socket so stdio can work on it.
1936                  */
1937                 if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1938                     fcntl(pdata, F_SETFL, flags & ~O_NONBLOCK) == -1)
1939                         goto pdata_err;
1940 #ifdef IP_TOS
1941                 if (from.su_family == AF_INET)
1942               {
1943                 tos = IPTOS_THROUGHPUT;
1944                 if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
1945                         syslog(LOG_WARNING, "pdata setsockopt (IP_TOS): %m");
1946               }
1947 #endif
1948                 reply(150, "Opening %s mode data connection for '%s'%s.",
1949                      type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
1950                 return (fdopen(pdata, mode));
1951 pdata_err:
1952                 reply(425, "Can't open data connection.");
1953                 (void) close(pdata);
1954                 pdata = -1;
1955                 return (NULL);
1956         }
1957         if (data >= 0) {
1958                 reply(125, "Using existing data connection for '%s'%s.",
1959                     name, sizebuf);
1960                 usedefault = 1;
1961                 return (fdopen(data, mode));
1962         }
1963         if (usedefault)
1964                 data_dest = his_addr;
1965         usedefault = 1;
1966         do {
1967                 file = getdatasock(mode);
1968                 if (file == NULL) {
1969                         char hostbuf[NI_MAXHOST], portbuf[NI_MAXSERV];
1970
1971                         if (getnameinfo((struct sockaddr *)&data_source,
1972                                 data_source.su_len,
1973                                 hostbuf, sizeof(hostbuf) - 1,
1974                                 portbuf, sizeof(portbuf) - 1,
1975                                 NI_NUMERICHOST|NI_NUMERICSERV))
1976                                         *hostbuf = *portbuf = 0;
1977                         hostbuf[sizeof(hostbuf) - 1] = 0;
1978                         portbuf[sizeof(portbuf) - 1] = 0;
1979                         reply(425, "Can't create data socket (%s,%s): %s.",
1980                                 hostbuf, portbuf, strerror(errno));
1981                         return (NULL);
1982                 }
1983                 data = fileno(file);
1984                 conerrno = 0;
1985                 if (connect(data, (struct sockaddr *)&data_dest,
1986                     data_dest.su_len) == 0)
1987                         break;
1988                 conerrno = errno;
1989                 (void) fclose(file);
1990                 data = -1;
1991                 if (conerrno == EADDRINUSE) {
1992                         sleep(swaitint);
1993                         retry += swaitint;
1994                 } else {
1995                         break;
1996                 }
1997         } while (retry <= swaitmax);
1998         if (conerrno != 0) {
1999                 reply(425, "Can't build data connection: %s.",
2000                            strerror(conerrno));
2001                 return (NULL);
2002         }
2003         reply(150, "Opening %s mode data connection for '%s'%s.",
2004              type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
2005         return (file);
2006 }
2007
2008 /*
2009  * A helper macro to avoid code duplication
2010  * in send_data() and receive_data().
2011  *
2012  * XXX We have to block SIGURG during putc() because BSD stdio
2013  * is unable to restart interrupted write operations and hence
2014  * the entire buffer contents will be lost as soon as a write()
2015  * call indicates EINTR to stdio.
2016  */
2017 #define FTPD_PUTC(ch, file, label)                                      \
2018         do {                                                            \
2019                 int ret;                                                \
2020                                                                         \
2021                 do {                                                    \
2022                         START_UNSAFE;                                   \
2023                         ret = putc((ch), (file));                       \
2024                         END_UNSAFE;                                     \
2025                         CHECKOOB(return (-1))                           \
2026                         else if (ferror(file))                          \
2027                                 goto label;                             \
2028                         clearerr(file);                                 \
2029                 } while (ret == EOF);                                   \
2030         } while (0)
2031
2032 /*
2033  * Tranfer the contents of "instr" to "outstr" peer using the appropriate
2034  * encapsulation of the data subject to Mode, Structure, and Type.
2035  *
2036  * NB: Form isn't handled.
2037  */
2038 static int
2039 send_data(FILE *instr, FILE *outstr, size_t blksize, off_t filesize, int isreg)
2040 {
2041         int c, cp, filefd, netfd;
2042         char *buf;
2043
2044         STARTXFER;
2045
2046         switch (type) {
2047
2048         case TYPE_A:
2049                 cp = EOF;
2050                 for (;;) {
2051                         c = getc(instr);
2052                         CHECKOOB(return (-1))
2053                         else if (c == EOF && ferror(instr))
2054                                 goto file_err;
2055                         if (c == EOF) {
2056                                 if (ferror(instr)) {    /* resume after OOB */
2057                                         clearerr(instr);
2058                                         continue;
2059                                 }
2060                                 if (feof(instr))        /* EOF */
2061                                         break;
2062                                 syslog(LOG_ERR, "Internal: impossible condition"
2063                                                 " on file after getc()");
2064                                 goto file_err;
2065                         }
2066                         if (c == '\n' && cp != '\r') {
2067                                 FTPD_PUTC('\r', outstr, data_err);
2068                                 byte_count++;
2069                         }
2070                         FTPD_PUTC(c, outstr, data_err);
2071                         byte_count++;
2072                         cp = c;
2073                 }
2074 #ifdef notyet   /* BSD stdio isn't ready for that */
2075                 while (fflush(outstr) == EOF) {
2076                         CHECKOOB(return (-1))
2077                         else
2078                                 goto data_err;
2079                         clearerr(outstr);
2080                 }
2081                 ENDXFER;
2082 #else
2083                 ENDXFER;
2084                 if (fflush(outstr) == EOF)
2085                         goto data_err;
2086 #endif
2087                 reply(226, "Transfer complete.");
2088                 return (0);
2089
2090         case TYPE_I:
2091         case TYPE_L:
2092                 /*
2093                  * isreg is only set if we are not doing restart and we
2094                  * are sending a regular file
2095                  */
2096                 netfd = fileno(outstr);
2097                 filefd = fileno(instr);
2098
2099                 if (isreg) {
2100                         char *msg = "Transfer complete.";
2101                         off_t cnt, offset;
2102                         int err;
2103
2104                         cnt = offset = 0;
2105
2106                         while (filesize > 0) {
2107                                 err = sendfile(filefd, netfd, offset, 0,
2108                                                NULL, &cnt, 0);
2109                                 /*
2110                                  * Calculate byte_count before OOB processing.
2111                                  * It can be used in myoob() later.
2112                                  */
2113                                 byte_count += cnt;
2114                                 offset += cnt;
2115                                 filesize -= cnt;
2116                                 CHECKOOB(return (-1))
2117                                 else if (err == -1) {
2118                                         if (errno != EINTR &&
2119                                             cnt == 0 && offset == 0)
2120                                                 goto oldway;
2121                                         goto data_err;
2122                                 }
2123                                 if (err == -1)  /* resume after OOB */
2124                                         continue;
2125                                 /*
2126                                  * We hit the EOF prematurely.
2127                                  * Perhaps the file was externally truncated.
2128                                  */
2129                                 if (cnt == 0) {
2130                                         msg = "Transfer finished due to "
2131                                               "premature end of file.";
2132                                         break;
2133                                 }
2134                         }
2135                         ENDXFER;
2136                         reply(226, msg);
2137                         return (0);
2138                 }
2139
2140 oldway:
2141                 if ((buf = malloc(blksize)) == NULL) {
2142                         ENDXFER;
2143                         reply(451, "Ran out of memory.");
2144                         return (-1);
2145                 }
2146
2147                 for (;;) {
2148                         int cnt, len;
2149                         char *bp;
2150
2151                         cnt = read(filefd, buf, blksize);
2152                         CHECKOOB(free(buf); return (-1))
2153                         else if (cnt < 0) {
2154                                 free(buf);
2155                                 goto file_err;
2156                         }
2157                         if (cnt < 0)    /* resume after OOB */
2158                                 continue;
2159                         if (cnt == 0)   /* EOF */
2160                                 break;
2161                         for (len = cnt, bp = buf; len > 0;) {
2162                                 cnt = write(netfd, bp, len);
2163                                 CHECKOOB(free(buf); return (-1))
2164                                 else if (cnt < 0) {
2165                                         free(buf);
2166                                         goto data_err;
2167                                 }
2168                                 if (cnt <= 0)
2169                                         continue;
2170                                 len -= cnt;
2171                                 bp += cnt;
2172                                 byte_count += cnt;
2173                         }
2174                 }
2175                 ENDXFER;
2176                 free(buf);
2177                 reply(226, "Transfer complete.");
2178                 return (0);
2179         default:
2180                 ENDXFER;
2181                 reply(550, "Unimplemented TYPE %d in send_data.", type);
2182                 return (-1);
2183         }
2184
2185 data_err:
2186         ENDXFER;
2187         perror_reply(426, "Data connection");
2188         return (-1);
2189
2190 file_err:
2191         ENDXFER;
2192         perror_reply(551, "Error on input file");
2193         return (-1);
2194 }
2195
2196 /*
2197  * Transfer data from peer to "outstr" using the appropriate encapulation of
2198  * the data subject to Mode, Structure, and Type.
2199  *
2200  * N.B.: Form isn't handled.
2201  */
2202 static int
2203 receive_data(FILE *instr, FILE *outstr)
2204 {
2205         int c, cp;
2206         int bare_lfs = 0;
2207
2208         STARTXFER;
2209
2210         switch (type) {
2211
2212         case TYPE_I:
2213         case TYPE_L:
2214                 for (;;) {
2215                         int cnt, len;
2216                         char *bp;
2217                         char buf[BUFSIZ];
2218
2219                         cnt = read(fileno(instr), buf, sizeof(buf));
2220                         CHECKOOB(return (-1))
2221                         else if (cnt < 0)
2222                                 goto data_err;
2223                         if (cnt < 0)    /* resume after OOB */
2224                                 continue;
2225                         if (cnt == 0)   /* EOF */
2226                                 break;
2227                         for (len = cnt, bp = buf; len > 0;) {
2228                                 cnt = write(fileno(outstr), bp, len);
2229                                 CHECKOOB(return (-1))
2230                                 else if (cnt < 0)
2231                                         goto file_err;
2232                                 if (cnt <= 0)
2233                                         continue;
2234                                 len -= cnt;
2235                                 bp += cnt;
2236                                 byte_count += cnt;
2237                         }
2238                 }
2239                 ENDXFER;
2240                 return (0);
2241
2242         case TYPE_E:
2243                 ENDXFER;
2244                 reply(553, "TYPE E not implemented.");
2245                 return (-1);
2246
2247         case TYPE_A:
2248                 cp = EOF;
2249                 for (;;) {
2250                         c = getc(instr);
2251                         CHECKOOB(return (-1))
2252                         else if (c == EOF && ferror(instr))
2253                                 goto data_err;
2254                         if (c == EOF && ferror(instr)) { /* resume after OOB */
2255                                 clearerr(instr);
2256                                 continue;
2257                         }
2258
2259                         if (cp == '\r') {
2260                                 if (c != '\n')
2261                                         FTPD_PUTC('\r', outstr, file_err);
2262                         } else
2263                                 if (c == '\n')
2264                                         bare_lfs++;
2265                         if (c == '\r') {
2266                                 byte_count++;
2267                                 cp = c;
2268                                 continue;
2269                         }
2270
2271                         /* Check for EOF here in order not to lose last \r. */
2272                         if (c == EOF) {
2273                                 if (feof(instr))        /* EOF */
2274                                         break;
2275                                 syslog(LOG_ERR, "Internal: impossible condition"
2276                                                 " on data stream after getc()");
2277                                 goto data_err;
2278                         }
2279
2280                         byte_count++;
2281                         FTPD_PUTC(c, outstr, file_err);
2282                         cp = c;
2283                 }
2284 #ifdef notyet   /* BSD stdio isn't ready for that */
2285                 while (fflush(outstr) == EOF) {
2286                         CHECKOOB(return (-1))
2287                         else
2288                                 goto file_err;
2289                         clearerr(outstr);
2290                 }
2291                 ENDXFER;
2292 #else
2293                 ENDXFER;
2294                 if (fflush(outstr) == EOF)
2295                         goto file_err;
2296 #endif
2297                 if (bare_lfs) {
2298                         lreply(226,
2299                 "WARNING! %d bare linefeeds received in ASCII mode.",
2300                             bare_lfs);
2301                 (void)printf("   File may not have transferred correctly.\r\n");
2302                 }
2303                 return (0);
2304         default:
2305                 ENDXFER;
2306                 reply(550, "Unimplemented TYPE %d in receive_data.", type);
2307                 return (-1);
2308         }
2309
2310 data_err:
2311         ENDXFER;
2312         perror_reply(426, "Data connection");
2313         return (-1);
2314
2315 file_err:
2316         ENDXFER;
2317         perror_reply(452, "Error writing to file");
2318         return (-1);
2319 }
2320
2321 void
2322 statfilecmd(char *filename)
2323 {
2324         FILE *fin;
2325         int atstart;
2326         int c, code;
2327         char line[LINE_MAX];
2328         struct stat st;
2329
2330         code = lstat(filename, &st) == 0 && S_ISDIR(st.st_mode) ? 212 : 213;
2331         (void)snprintf(line, sizeof(line), _PATH_LS " -lgA %s", filename);
2332         fin = ftpd_popen(line, "r");
2333         lreply(code, "Status of %s:", filename);
2334         atstart = 1;
2335         while ((c = getc(fin)) != EOF) {
2336                 if (c == '\n') {
2337                         if (ferror(stdout)){
2338                                 perror_reply(421, "Control connection");
2339                                 (void) ftpd_pclose(fin);
2340                                 dologout(1);
2341                                 /* NOTREACHED */
2342                         }
2343                         if (ferror(fin)) {
2344                                 perror_reply(551, filename);
2345                                 (void) ftpd_pclose(fin);
2346                                 return;
2347                         }
2348                         (void) putc('\r', stdout);
2349                 }
2350                 /*
2351                  * RFC 959 says neutral text should be prepended before
2352                  * a leading 3-digit number followed by whitespace, but
2353                  * many ftp clients can be confused by any leading digits,
2354                  * as a matter of fact.
2355                  */
2356                 if (atstart && isdigit(c))
2357                         (void) putc(' ', stdout);
2358                 (void) putc(c, stdout);
2359                 atstart = (c == '\n');
2360         }
2361         (void) ftpd_pclose(fin);
2362         reply(code, "End of status.");
2363 }
2364
2365 void
2366 statcmd(void)
2367 {
2368         union sockunion *su;
2369         u_char *a, *p;
2370         char hname[NI_MAXHOST];
2371         int ispassive;
2372
2373         if (hostinfo) {
2374                 lreply(211, "%s FTP server status:", hostname);
2375                 printf("     %s\r\n", version);
2376         } else
2377                 lreply(211, "FTP server status:");
2378         printf("     Connected to %s", remotehost);
2379         if (!getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
2380                          hname, sizeof(hname) - 1, NULL, 0, NI_NUMERICHOST)) {
2381                 hname[sizeof(hname) - 1] = 0;
2382                 if (strcmp(hname, remotehost) != 0)
2383                         printf(" (%s)", hname);
2384         }
2385         printf("\r\n");
2386         if (logged_in) {
2387                 if (guest)
2388                         printf("     Logged in anonymously\r\n");
2389                 else
2390                         printf("     Logged in as %s\r\n", pw->pw_name);
2391         } else if (askpasswd)
2392                 printf("     Waiting for password\r\n");
2393         else
2394                 printf("     Waiting for user name\r\n");
2395         printf("     TYPE: %s", typenames[type]);
2396         if (type == TYPE_A || type == TYPE_E)
2397                 printf(", FORM: %s", formnames[form]);
2398         if (type == TYPE_L)
2399 #if CHAR_BIT == 8
2400                 printf(" %d", CHAR_BIT);
2401 #else
2402                 printf(" %d", bytesize);        /* need definition! */
2403 #endif
2404         printf("; STRUcture: %s; transfer MODE: %s\r\n",
2405             strunames[stru], modenames[mode]);
2406         if (data != -1)
2407                 printf("     Data connection open\r\n");
2408         else if (pdata != -1) {
2409                 ispassive = 1;
2410                 su = &pasv_addr;
2411                 goto printaddr;
2412         } else if (usedefault == 0) {
2413                 ispassive = 0;
2414                 su = &data_dest;
2415 printaddr:
2416 #define UC(b) (((int) b) & 0xff)
2417                 if (epsvall) {
2418                         printf("     EPSV only mode (EPSV ALL)\r\n");
2419                         goto epsvonly;
2420                 }
2421
2422                 /* PORT/PASV */
2423                 if (su->su_family == AF_INET) {
2424                         a = (u_char *) &su->su_sin.sin_addr;
2425                         p = (u_char *) &su->su_sin.sin_port;
2426                         printf("     %s (%d,%d,%d,%d,%d,%d)\r\n",
2427                                 ispassive ? "PASV" : "PORT",
2428                                 UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2429                                 UC(p[0]), UC(p[1]));
2430                 }
2431
2432                 /* LPRT/LPSV */
2433             {
2434                 int alen, af, i;
2435
2436                 switch (su->su_family) {
2437                 case AF_INET:
2438                         a = (u_char *) &su->su_sin.sin_addr;
2439                         p = (u_char *) &su->su_sin.sin_port;
2440                         alen = sizeof(su->su_sin.sin_addr);
2441                         af = 4;
2442                         break;
2443                 case AF_INET6:
2444                         a = (u_char *) &su->su_sin6.sin6_addr;
2445                         p = (u_char *) &su->su_sin6.sin6_port;
2446                         alen = sizeof(su->su_sin6.sin6_addr);
2447                         af = 6;
2448                         break;
2449                 default:
2450                         af = 0;
2451                         break;
2452                 }
2453                 if (af) {
2454                         printf("     %s (%d,%d,", ispassive ? "LPSV" : "LPRT",
2455                                 af, alen);
2456                         for (i = 0; i < alen; i++)
2457                                 printf("%d,", UC(a[i]));
2458                         printf("%d,%d,%d)\r\n", 2, UC(p[0]), UC(p[1]));
2459                 }
2460             }
2461
2462 epsvonly:;
2463                 /* EPRT/EPSV */
2464             {
2465                 int af;
2466
2467                 switch (su->su_family) {
2468                 case AF_INET:
2469                         af = 1;
2470                         break;
2471                 case AF_INET6:
2472                         af = 2;
2473                         break;
2474                 default:
2475                         af = 0;
2476                         break;
2477                 }
2478                 if (af) {
2479                         union sockunion tmp;
2480
2481                         tmp = *su;
2482                         if (tmp.su_family == AF_INET6)
2483                                 tmp.su_sin6.sin6_scope_id = 0;
2484                         if (!getnameinfo((struct sockaddr *)&tmp, tmp.su_len,
2485                                         hname, sizeof(hname) - 1, NULL, 0,
2486                                         NI_NUMERICHOST)) {
2487                                 hname[sizeof(hname) - 1] = 0;
2488                                 printf("     %s |%d|%s|%d|\r\n",
2489                                         ispassive ? "EPSV" : "EPRT",
2490                                         af, hname, htons(tmp.su_port));
2491                         }
2492                 }
2493             }
2494 #undef UC
2495         } else
2496                 printf("     No data connection\r\n");
2497         reply(211, "End of status.");
2498 }
2499
2500 void
2501 fatalerror(char *s)
2502 {
2503
2504         reply(451, "Error in server: %s", s);
2505         reply(221, "Closing connection due to server error.");
2506         dologout(0);
2507         /* NOTREACHED */
2508 }
2509
2510 void
2511 reply(int n, const char *fmt, ...)
2512 {
2513         va_list ap;
2514
2515         (void)printf("%d ", n);
2516         va_start(ap, fmt);
2517         (void)vprintf(fmt, ap);
2518         va_end(ap);
2519         (void)printf("\r\n");
2520         (void)fflush(stdout);
2521         if (ftpdebug) {
2522                 syslog(LOG_DEBUG, "<--- %d ", n);
2523                 va_start(ap, fmt);
2524                 vsyslog(LOG_DEBUG, fmt, ap);
2525                 va_end(ap);
2526         }
2527 }
2528
2529 void
2530 lreply(int n, const char *fmt, ...)
2531 {
2532         va_list ap;
2533
2534         (void)printf("%d- ", n);
2535         va_start(ap, fmt);
2536         (void)vprintf(fmt, ap);
2537         va_end(ap);
2538         (void)printf("\r\n");
2539         (void)fflush(stdout);
2540         if (ftpdebug) {
2541                 syslog(LOG_DEBUG, "<--- %d- ", n);
2542                 va_start(ap, fmt);
2543                 vsyslog(LOG_DEBUG, fmt, ap);
2544                 va_end(ap);
2545         }
2546 }
2547
2548 static void
2549 ack(char *s)
2550 {
2551
2552         reply(250, "%s command successful.", s);
2553 }
2554
2555 void
2556 nack(char *s)
2557 {
2558
2559         reply(502, "%s command not implemented.", s);
2560 }
2561
2562 /* ARGSUSED */
2563 void
2564 yyerror(char *s)
2565 {
2566         char *cp;
2567
2568         if ((cp = strchr(cbuf,'\n')))
2569                 *cp = '\0';
2570         reply(500, "%s: command not understood.", cbuf);
2571 }
2572
2573 void
2574 delete(char *name)
2575 {
2576         struct stat st;
2577
2578         LOGCMD("delete", name);
2579         if (lstat(name, &st) < 0) {
2580                 perror_reply(550, name);
2581                 return;
2582         }
2583         if (S_ISDIR(st.st_mode)) {
2584                 if (rmdir(name) < 0) {
2585                         perror_reply(550, name);
2586                         return;
2587                 }
2588                 goto done;
2589         }
2590         if (guest && noguestmod) {
2591                 reply(550, "Operation not permitted.");
2592                 return;
2593         }
2594         if (unlink(name) < 0) {
2595                 perror_reply(550, name);
2596                 return;
2597         }
2598 done:
2599         ack("DELE");
2600 }
2601
2602 void
2603 cwd(char *path)
2604 {
2605
2606         if (chdir(path) < 0)
2607                 perror_reply(550, path);
2608         else
2609                 ack("CWD");
2610 }
2611
2612 void
2613 makedir(char *name)
2614 {
2615         char *s;
2616
2617         LOGCMD("mkdir", name);
2618         if (guest && noguestmkd)
2619                 reply(550, "Operation not permitted.");
2620         else if (mkdir(name, 0777) < 0)
2621                 perror_reply(550, name);
2622         else {
2623                 if ((s = doublequote(name)) == NULL)
2624                         fatalerror("Ran out of memory.");
2625                 reply(257, "\"%s\" directory created.", s);
2626                 free(s);
2627         }
2628 }
2629
2630 void
2631 removedir(char *name)
2632 {
2633
2634         LOGCMD("rmdir", name);
2635         if (rmdir(name) < 0)
2636                 perror_reply(550, name);
2637         else
2638                 ack("RMD");
2639 }
2640
2641 void
2642 pwd(void)
2643 {
2644         char *s, path[MAXPATHLEN + 1];
2645
2646         if (getcwd(path, sizeof(path)) == NULL)
2647                 perror_reply(550, "Get current directory");
2648         else {
2649                 if ((s = doublequote(path)) == NULL)
2650                         fatalerror("Ran out of memory.");
2651                 reply(257, "\"%s\" is current directory.", s);
2652                 free(s);
2653         }
2654 }
2655
2656 char *
2657 renamefrom(char *name)
2658 {
2659         struct stat st;
2660
2661         if (guest && noguestmod) {
2662                 reply(550, "Operation not permitted.");
2663                 return (NULL);
2664         }
2665         if (lstat(name, &st) < 0) {
2666                 perror_reply(550, name);
2667                 return (NULL);
2668         }
2669         reply(350, "File exists, ready for destination name.");
2670         return (name);
2671 }
2672
2673 void
2674 renamecmd(char *from, char *to)
2675 {
2676         struct stat st;
2677
2678         LOGCMD2("rename", from, to);
2679
2680         if (guest && (stat(to, &st) == 0)) {
2681                 reply(550, "%s: permission denied.", to);
2682                 return;
2683         }
2684
2685         if (rename(from, to) < 0)
2686                 perror_reply(550, "rename");
2687         else
2688                 ack("RNTO");
2689 }
2690
2691 static void
2692 dolog(struct sockaddr *who)
2693 {
2694         char who_name[NI_MAXHOST];
2695
2696         realhostname_sa(remotehost, sizeof(remotehost) - 1, who, who->sa_len);
2697         remotehost[sizeof(remotehost) - 1] = 0;
2698         if (getnameinfo(who, who->sa_len,
2699                 who_name, sizeof(who_name) - 1, NULL, 0, NI_NUMERICHOST))
2700                         *who_name = 0;
2701         who_name[sizeof(who_name) - 1] = 0;
2702
2703 #ifdef SETPROCTITLE
2704 #ifdef VIRTUAL_HOSTING
2705         if (thishost != firsthost)
2706                 snprintf(proctitle, sizeof(proctitle), "%s: connected (to %s)",
2707                          remotehost, hostname);
2708         else
2709 #endif
2710                 snprintf(proctitle, sizeof(proctitle), "%s: connected",
2711                          remotehost);
2712         setproctitle("%s", proctitle);
2713 #endif /* SETPROCTITLE */
2714
2715         if (logging) {
2716 #ifdef VIRTUAL_HOSTING
2717                 if (thishost != firsthost)
2718                         syslog(LOG_INFO, "connection from %s (%s) to %s",
2719                                remotehost, who_name, hostname);
2720                 else
2721 #endif
2722                         syslog(LOG_INFO, "connection from %s (%s)",
2723                                remotehost, who_name);
2724         }
2725 }
2726
2727 /*
2728  * Record logout in wtmp file
2729  * and exit with supplied status.
2730  */
2731 void
2732 dologout(int status)
2733 {
2734
2735         if (logged_in && dowtmp) {
2736                 (void) seteuid(0);
2737                 ftpd_logwtmp(ttyline, "", NULL);
2738         }
2739         /* beware of flushing buffers after a SIGPIPE */
2740         _exit(status);
2741 }
2742
2743 static void
2744 sigurg(int signo)
2745 {
2746
2747         recvurg = 1;
2748 }
2749
2750 static void
2751 maskurg(int flag)
2752 {
2753         int oerrno;
2754         sigset_t sset;
2755
2756         if (!transflag) {
2757                 syslog(LOG_ERR, "Internal: maskurg() while no transfer");
2758                 return;
2759         }
2760         oerrno = errno;
2761         sigemptyset(&sset);
2762         sigaddset(&sset, SIGURG);
2763         sigprocmask(flag ? SIG_BLOCK : SIG_UNBLOCK, &sset, NULL);
2764         errno = oerrno;
2765 }
2766
2767 static void
2768 flagxfer(int flag)
2769 {
2770
2771         if (flag) {
2772                 if (transflag)
2773                         syslog(LOG_ERR, "Internal: flagxfer(1): "
2774                                         "transfer already under way");
2775                 transflag = 1;
2776                 maskurg(0);
2777                 recvurg = 0;
2778         } else {
2779                 if (!transflag)
2780                         syslog(LOG_ERR, "Internal: flagxfer(0): "
2781                                         "no active transfer");
2782                 maskurg(1);
2783                 transflag = 0;
2784         }
2785 }
2786
2787 /*
2788  * Returns 0 if OK to resume or -1 if abort requested.
2789  */
2790 static int
2791 myoob(void)
2792 {
2793         char *cp;
2794         int ret;
2795
2796         if (!transflag) {
2797                 syslog(LOG_ERR, "Internal: myoob() while no transfer");
2798                 return (0);
2799         }
2800         cp = tmpline;
2801         ret = getline(cp, 7, stdin);
2802         if (ret == -1) {
2803                 reply(221, "You could at least say goodbye.");
2804                 dologout(0);
2805         } else if (ret == -2) {
2806                 /* Ignore truncated command. */
2807                 return (0);
2808         }
2809         upper(cp);
2810         if (strcmp(cp, "ABOR\r\n") == 0) {
2811                 tmpline[0] = '\0';
2812                 reply(426, "Transfer aborted. Data connection closed.");
2813                 reply(226, "Abort successful.");
2814                 return (-1);
2815         }
2816         if (strcmp(cp, "STAT\r\n") == 0) {
2817                 tmpline[0] = '\0';
2818                 if (file_size != -1)
2819                         reply(213, "Status: %jd of %jd bytes transferred.",
2820                                    (intmax_t)byte_count, (intmax_t)file_size);
2821                 else
2822                         reply(213, "Status: %jd bytes transferred.",
2823                                    (intmax_t)byte_count);
2824         }
2825         return (0);
2826 }
2827
2828 /*
2829  * Note: a response of 425 is not mentioned as a possible response to
2830  *      the PASV command in RFC959. However, it has been blessed as
2831  *      a legitimate response by Jon Postel in a telephone conversation
2832  *      with Rick Adams on 25 Jan 89.
2833  */
2834 void
2835 passive(void)
2836 {
2837         socklen_t len;
2838         int on;
2839         char *p, *a;
2840
2841         if (pdata >= 0)         /* close old port if one set */
2842                 close(pdata);
2843
2844         pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2845         if (pdata < 0) {
2846                 perror_reply(425, "Can't open passive connection");
2847                 return;
2848         }
2849         on = 1;
2850         if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2851                 syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2852
2853         (void) seteuid(0);
2854
2855 #ifdef IP_PORTRANGE
2856         if (ctrl_addr.su_family == AF_INET) {
2857             on = restricted_data_ports ? IP_PORTRANGE_HIGH
2858                                        : IP_PORTRANGE_DEFAULT;
2859
2860             if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2861                             &on, sizeof(on)) < 0)
2862                     goto pasv_error;
2863         }
2864 #endif
2865 #ifdef IPV6_PORTRANGE
2866         if (ctrl_addr.su_family == AF_INET6) {
2867             on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2868                                        : IPV6_PORTRANGE_DEFAULT;
2869
2870             if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2871                             &on, sizeof(on)) < 0)
2872                     goto pasv_error;
2873         }
2874 #endif
2875
2876         pasv_addr = ctrl_addr;
2877         pasv_addr.su_port = 0;
2878         if (bind(pdata, (struct sockaddr *)&pasv_addr, pasv_addr.su_len) < 0)
2879                 goto pasv_error;
2880
2881         (void) seteuid(pw->pw_uid);
2882
2883         len = sizeof(pasv_addr);
2884         if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2885                 goto pasv_error;
2886         if (listen(pdata, 1) < 0)
2887                 goto pasv_error;
2888         if (pasv_addr.su_family == AF_INET)
2889                 a = (char *) &pasv_addr.su_sin.sin_addr;
2890         else if (pasv_addr.su_family == AF_INET6 &&
2891                  IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr))
2892                 a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
2893         else
2894                 goto pasv_error;
2895
2896         p = (char *) &pasv_addr.su_port;
2897
2898 #define UC(b) (((int) b) & 0xff)
2899
2900         reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
2901                 UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
2902         return;
2903
2904 pasv_error:
2905         (void) seteuid(pw->pw_uid);
2906         (void) close(pdata);
2907         pdata = -1;
2908         perror_reply(425, "Can't open passive connection");
2909         return;
2910 }
2911
2912 /*
2913  * Long Passive defined in RFC 1639.
2914  *     228 Entering Long Passive Mode
2915  *         (af, hal, h1, h2, h3,..., pal, p1, p2...)
2916  */
2917
2918 void
2919 long_passive(char *cmd, int pf)
2920 {
2921         socklen_t len;
2922         int on;
2923         char *p, *a;
2924
2925         if (pdata >= 0)         /* close old port if one set */
2926                 close(pdata);
2927
2928         if (pf != PF_UNSPEC) {
2929                 if (ctrl_addr.su_family != pf) {
2930                         switch (ctrl_addr.su_family) {
2931                         case AF_INET:
2932                                 pf = 1;
2933                                 break;
2934                         case AF_INET6:
2935                                 pf = 2;
2936                                 break;
2937                         default:
2938                                 pf = 0;
2939                                 break;
2940                         }
2941                         /*
2942                          * XXX
2943                          * only EPRT/EPSV ready clients will understand this
2944                          */
2945                         if (strcmp(cmd, "EPSV") == 0 && pf) {
2946                                 reply(522, "Network protocol mismatch, "
2947                                         "use (%d)", pf);
2948                         } else
2949                                 reply(501, "Network protocol mismatch."); /*XXX*/
2950
2951                         return;
2952                 }
2953         }
2954
2955         pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2956         if (pdata < 0) {
2957                 perror_reply(425, "Can't open passive connection");
2958                 return;
2959         }
2960         on = 1;
2961         if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2962                 syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2963
2964         (void) seteuid(0);
2965
2966         pasv_addr = ctrl_addr;
2967         pasv_addr.su_port = 0;
2968         len = pasv_addr.su_len;
2969
2970 #ifdef IP_PORTRANGE
2971         if (ctrl_addr.su_family == AF_INET) {
2972             on = restricted_data_ports ? IP_PORTRANGE_HIGH
2973                                        : IP_PORTRANGE_DEFAULT;
2974
2975             if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2976                             &on, sizeof(on)) < 0)
2977                     goto pasv_error;
2978         }
2979 #endif
2980 #ifdef IPV6_PORTRANGE
2981         if (ctrl_addr.su_family == AF_INET6) {
2982             on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2983                                        : IPV6_PORTRANGE_DEFAULT;
2984
2985             if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2986                             &on, sizeof(on)) < 0)
2987                     goto pasv_error;
2988         }
2989 #endif
2990
2991         if (bind(pdata, (struct sockaddr *)&pasv_addr, len) < 0)
2992                 goto pasv_error;
2993
2994         (void) seteuid(pw->pw_uid);
2995
2996         if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2997                 goto pasv_error;
2998         if (listen(pdata, 1) < 0)
2999                 goto pasv_error;
3000
3001 #define UC(b) (((int) b) & 0xff)
3002
3003         if (strcmp(cmd, "LPSV") == 0) {
3004                 p = (char *)&pasv_addr.su_port;
3005                 switch (pasv_addr.su_family) {
3006                 case AF_INET:
3007                         a = (char *) &pasv_addr.su_sin.sin_addr;
3008                 v4_reply:
3009                         reply(228,
3010 "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3011                               4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3012                               2, UC(p[0]), UC(p[1]));
3013                         return;
3014                 case AF_INET6:
3015                         if (IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr)) {
3016                                 a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
3017                                 goto v4_reply;
3018                         }
3019                         a = (char *) &pasv_addr.su_sin6.sin6_addr;
3020                         reply(228,
3021 "Entering Long Passive Mode "
3022 "(%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3023                               6, 16, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3024                               UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
3025                               UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
3026                               UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
3027                               2, UC(p[0]), UC(p[1]));
3028                         return;
3029                 }
3030         } else if (strcmp(cmd, "EPSV") == 0) {
3031                 switch (pasv_addr.su_family) {
3032                 case AF_INET:
3033                 case AF_INET6:
3034                         reply(229, "Entering Extended Passive Mode (|||%d|)",
3035                                 ntohs(pasv_addr.su_port));
3036                         return;
3037                 }
3038         } else {
3039                 /* more proper error code? */
3040         }
3041
3042 pasv_error:
3043         (void) seteuid(pw->pw_uid);
3044         (void) close(pdata);
3045         pdata = -1;
3046         perror_reply(425, "Can't open passive connection");
3047         return;
3048 }
3049
3050 /*
3051  * Generate unique name for file with basename "local"
3052  * and open the file in order to avoid possible races.
3053  * Try "local" first, then "local.1", "local.2" etc, up to "local.99".
3054  * Return descriptor to the file, set "name" to its name.
3055  *
3056  * Generates failure reply on error.
3057  */
3058 static int
3059 guniquefd(char *local, char **name)
3060 {
3061         static char new[MAXPATHLEN];
3062         struct stat st;
3063         char *cp;
3064         int count;
3065         int fd;
3066
3067         cp = strrchr(local, '/');
3068         if (cp)
3069                 *cp = '\0';
3070         if (stat(cp ? local : ".", &st) < 0) {
3071                 perror_reply(553, cp ? local : ".");
3072                 return (-1);
3073         }
3074         if (cp) {
3075                 /*
3076                  * Let not overwrite dirname with counter suffix.
3077                  * -4 is for /nn\0
3078                  * In this extreme case dot won't be put in front of suffix.
3079                  */
3080                 if (strlen(local) > sizeof(new) - 4) {
3081                         reply(553, "Pathname too long.");
3082                         return (-1);
3083                 }
3084                 *cp = '/';
3085         }
3086         /* -4 is for the .nn<null> we put on the end below */
3087         (void) snprintf(new, sizeof(new) - 4, "%s", local);
3088         cp = new + strlen(new);
3089         /*
3090          * Don't generate dotfile unless requested explicitly.
3091          * This covers the case when basename gets truncated off
3092          * by buffer size.
3093          */
3094         if (cp > new && cp[-1] != '/')
3095                 *cp++ = '.';
3096         for (count = 0; count < 100; count++) {
3097                 /* At count 0 try unmodified name */
3098                 if (count)
3099                         (void)sprintf(cp, "%d", count);
3100                 if ((fd = open(count ? new : local,
3101                     O_RDWR | O_CREAT | O_EXCL, 0666)) >= 0) {
3102                         *name = count ? new : local;
3103                         return (fd);
3104                 }
3105                 if (errno != EEXIST) {
3106                         perror_reply(553, count ? new : local);
3107                         return (-1);
3108                 }
3109         }
3110         reply(452, "Unique file name cannot be created.");
3111         return (-1);
3112 }
3113
3114 /*
3115  * Format and send reply containing system error number.
3116  */
3117 void
3118 perror_reply(int code, char *string)
3119 {
3120
3121         reply(code, "%s: %s.", string, strerror(errno));
3122 }
3123
3124 static char *onefile[] = {
3125         "",
3126         0
3127 };
3128
3129 void
3130 send_file_list(char *whichf)
3131 {
3132         struct stat st;
3133         DIR *dirp = NULL;
3134         struct dirent *dir;
3135         FILE *dout = NULL;
3136         char **dirlist, *dirname;
3137         int simple = 0;
3138         int freeglob = 0;
3139         glob_t gl;
3140
3141         if (strpbrk(whichf, "~{[*?") != NULL) {
3142                 int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
3143
3144                 memset(&gl, 0, sizeof(gl));
3145                 gl.gl_matchc = MAXGLOBARGS;
3146                 flags |= GLOB_LIMIT;
3147                 freeglob = 1;
3148                 if (glob(whichf, flags, 0, &gl)) {
3149                         reply(550, "No matching files found.");
3150                         goto out;
3151                 } else if (gl.gl_pathc == 0) {
3152                         errno = ENOENT;
3153                         perror_reply(550, whichf);
3154                         goto out;
3155                 }
3156                 dirlist = gl.gl_pathv;
3157         } else {
3158                 onefile[0] = whichf;
3159                 dirlist = onefile;
3160                 simple = 1;
3161         }
3162
3163         while ((dirname = *dirlist++)) {
3164                 if (stat(dirname, &st) < 0) {
3165                         /*
3166                          * If user typed "ls -l", etc, and the client
3167                          * used NLST, do what the user meant.
3168                          */
3169                         if (dirname[0] == '-' && *dirlist == NULL &&
3170                             dout == NULL)
3171                                 retrieve(_PATH_LS " %s", dirname);
3172                         else
3173                                 perror_reply(550, whichf);
3174                         goto out;
3175                 }
3176
3177                 if (S_ISREG(st.st_mode)) {
3178                         if (dout == NULL) {
3179                                 dout = dataconn("file list", -1, "w");
3180                                 if (dout == NULL)
3181                                         goto out;
3182                                 STARTXFER;
3183                         }
3184                         START_UNSAFE;
3185                         fprintf(dout, "%s%s\n", dirname,
3186                                 type == TYPE_A ? "\r" : "");
3187                         END_UNSAFE;
3188                         if (ferror(dout))
3189                                 goto data_err;
3190                         byte_count += strlen(dirname) +
3191                                       (type == TYPE_A ? 2 : 1);
3192                         CHECKOOB(goto abrt);
3193                         continue;
3194                 } else if (!S_ISDIR(st.st_mode))
3195                         continue;
3196
3197                 if ((dirp = opendir(dirname)) == NULL)
3198                         continue;
3199
3200                 while ((dir = readdir(dirp)) != NULL) {
3201                         char nbuf[MAXPATHLEN];
3202
3203                         CHECKOOB(goto abrt);
3204
3205                         if (dir->d_name[0] == '.' && dir->d_namlen == 1)
3206                                 continue;
3207                         if (dir->d_name[0] == '.' && dir->d_name[1] == '.' &&
3208                             dir->d_namlen == 2)
3209                                 continue;
3210
3211                         snprintf(nbuf, sizeof(nbuf),
3212                                 "%s/%s", dirname, dir->d_name);
3213
3214                         /*
3215                          * We have to do a stat to insure it's
3216                          * not a directory or special file.
3217                          */
3218                         if (simple || (stat(nbuf, &st) == 0 &&
3219                             S_ISREG(st.st_mode))) {
3220                                 if (dout == NULL) {
3221                                         dout = dataconn("file list", -1, "w");
3222                                         if (dout == NULL)
3223                                                 goto out;
3224                                         STARTXFER;
3225                                 }
3226                                 START_UNSAFE;
3227                                 if (nbuf[0] == '.' && nbuf[1] == '/')
3228                                         fprintf(dout, "%s%s\n", &nbuf[2],
3229                                                 type == TYPE_A ? "\r" : "");
3230                                 else
3231                                         fprintf(dout, "%s%s\n", nbuf,
3232                                                 type == TYPE_A ? "\r" : "");
3233                                 END_UNSAFE;
3234                                 if (ferror(dout))
3235                                         goto data_err;
3236                                 byte_count += strlen(nbuf) +
3237                                               (type == TYPE_A ? 2 : 1);
3238                                 CHECKOOB(goto abrt);
3239                         }
3240                 }
3241                 (void) closedir(dirp);
3242                 dirp = NULL;
3243         }
3244
3245         if (dout == NULL)
3246                 reply(550, "No files found.");
3247         else if (ferror(dout))
3248 data_err:       perror_reply(550, "Data connection");
3249         else
3250                 reply(226, "Transfer complete.");
3251 out:
3252         if (dout) {
3253                 ENDXFER;
3254 abrt:
3255                 (void) fclose(dout);
3256                 data = -1;
3257                 pdata = -1;
3258         }
3259         if (dirp)
3260                 (void) closedir(dirp);
3261         if (freeglob) {
3262                 freeglob = 0;
3263                 globfree(&gl);
3264         }
3265 }
3266
3267 void
3268 reapchild(int signo)
3269 {
3270         while (waitpid(-1, NULL, WNOHANG) > 0);
3271 }
3272
3273 #ifdef OLD_SETPROCTITLE
3274 /*
3275  * Clobber argv so ps will show what we're doing.  (Stolen from sendmail.)
3276  * Warning, since this is usually started from inetd.conf, it often doesn't
3277  * have much of an environment or arglist to overwrite.
3278  */
3279 void
3280 setproctitle(const char *fmt, ...)
3281 {
3282         int i;
3283         va_list ap;
3284         char *p, *bp, ch;
3285         char buf[LINE_MAX];
3286
3287         va_start(ap, fmt);
3288         (void)vsnprintf(buf, sizeof(buf), fmt, ap);
3289
3290         /* make ps print our process name */
3291         p = Argv[0];
3292         *p++ = '-';
3293
3294         i = strlen(buf);
3295         if (i > LastArgv - p - 2) {
3296                 i = LastArgv - p - 2;
3297                 buf[i] = '\0';
3298         }
3299         bp = buf;
3300         while (ch = *bp++)
3301                 if (ch != '\n' && ch != '\r')
3302                         *p++ = ch;
3303         while (p < LastArgv)
3304                 *p++ = ' ';
3305 }
3306 #endif /* OLD_SETPROCTITLE */
3307
3308 static void
3309 appendf(char **strp, char *fmt, ...)
3310 {
3311         va_list ap;
3312         char *ostr, *p;
3313
3314         va_start(ap, fmt);
3315         vasprintf(&p, fmt, ap);
3316         va_end(ap);
3317         if (p == NULL)
3318                 fatalerror("Ran out of memory.");
3319         if (*strp == NULL)
3320                 *strp = p;
3321         else {
3322                 ostr = *strp;
3323                 asprintf(strp, "%s%s", ostr, p);
3324                 if (*strp == NULL)
3325                         fatalerror("Ran out of memory.");
3326                 free(ostr);
3327         }
3328 }
3329
3330 static void
3331 logcmd(char *cmd, char *file1, char *file2, off_t cnt)
3332 {
3333         char *msg = NULL;
3334         char wd[MAXPATHLEN + 1];
3335
3336         if (logging <= 1)
3337                 return;
3338
3339         if (getcwd(wd, sizeof(wd) - 1) == NULL)
3340                 strcpy(wd, strerror(errno));
3341
3342         appendf(&msg, "%s", cmd);
3343         if (file1)
3344                 appendf(&msg, " %s", file1);
3345         if (file2)
3346                 appendf(&msg, " %s", file2);
3347         if (cnt >= 0)
3348                 appendf(&msg, " = %jd bytes", (intmax_t)cnt);
3349         appendf(&msg, " (wd: %s", wd);
3350         if (guest || dochroot)
3351                 appendf(&msg, "; chrooted");
3352         appendf(&msg, ")");
3353         syslog(LOG_INFO, "%s", msg);
3354         free(msg);
3355 }
3356
3357 static void
3358 logxfer(char *name, off_t size, time_t start)
3359 {
3360         char buf[MAXPATHLEN + 1024];
3361         char path[MAXPATHLEN + 1];
3362         time_t now;
3363
3364         if (statfd >= 0) {
3365                 time(&now);
3366                 if (realpath(name, path) == NULL) {
3367                         syslog(LOG_NOTICE, "realpath failed on %s: %m", path);
3368                         return;
3369                 }
3370                 snprintf(buf, sizeof(buf), "%.20s!%s!%s!%s!%jd!%ld\n",
3371                         ctime(&now)+4, ident, remotehost,
3372                         path, (intmax_t)size,
3373                         (long)(now - start + (now == start)));
3374                 write(statfd, buf, strlen(buf));
3375         }
3376 }
3377
3378 static char *
3379 doublequote(char *s)
3380 {
3381         int n;
3382         char *p, *s2;
3383
3384         for (p = s, n = 0; *p; p++)
3385                 if (*p == '"')
3386                         n++;
3387
3388         if ((s2 = malloc(p - s + n + 1)) == NULL)
3389                 return (NULL);
3390
3391         for (p = s2; *s; s++, p++) {
3392                 if ((*p = *s) == '"')
3393                         *(++p) = '"';
3394         }
3395         *p = '\0';
3396
3397         return (s2);
3398 }
3399
3400 /* setup server socket for specified address family */
3401 /* if af is PF_UNSPEC more than one socket may be returned */
3402 /* the returned list is dynamically allocated, so caller needs to free it */
3403 static int *
3404 socksetup(int af, char *bindname, const char *bindport)
3405 {
3406         struct addrinfo hints, *res, *r;
3407         int error, maxs, *s, *socks;
3408         const int on = 1;
3409
3410         memset(&hints, 0, sizeof(hints));
3411         hints.ai_flags = AI_PASSIVE;
3412         hints.ai_family = af;
3413         hints.ai_socktype = SOCK_STREAM;
3414         error = getaddrinfo(bindname, bindport, &hints, &res);
3415         if (error) {
3416                 syslog(LOG_ERR, "%s", gai_strerror(error));
3417                 if (error == EAI_SYSTEM)
3418                         syslog(LOG_ERR, "%s", strerror(errno));
3419                 return NULL;
3420         }
3421
3422         /* Count max number of sockets we may open */
3423         for (maxs = 0, r = res; r; r = r->ai_next, maxs++)
3424                 ;
3425         socks = malloc((maxs + 1) * sizeof(int));
3426         if (!socks) {
3427                 freeaddrinfo(res);
3428                 syslog(LOG_ERR, "couldn't allocate memory for sockets");
3429                 return NULL;
3430         }
3431
3432         *socks = 0;   /* num of sockets counter at start of array */
3433         s = socks + 1;
3434         for (r = res; r; r = r->ai_next) {
3435                 *s = socket(r->ai_family, r->ai_socktype, r->ai_protocol);
3436                 if (*s < 0) {
3437                         syslog(LOG_DEBUG, "control socket: %m");
3438                         continue;
3439                 }
3440                 if (setsockopt(*s, SOL_SOCKET, SO_REUSEADDR,
3441                     &on, sizeof(on)) < 0)
3442                         syslog(LOG_WARNING,
3443                             "control setsockopt (SO_REUSEADDR): %m");
3444                 if (r->ai_family == AF_INET6) {
3445                         if (setsockopt(*s, IPPROTO_IPV6, IPV6_V6ONLY,
3446                             &on, sizeof(on)) < 0)
3447                                 syslog(LOG_WARNING,
3448                                     "control setsockopt (IPV6_V6ONLY): %m");
3449                 }
3450                 if (bind(*s, r->ai_addr, r->ai_addrlen) < 0) {
3451                         syslog(LOG_DEBUG, "control bind: %m");
3452                         close(*s);
3453                         continue;
3454                 }
3455                 (*socks)++;
3456                 s++;
3457         }
3458
3459         if (res)
3460                 freeaddrinfo(res);
3461
3462         if (*socks == 0) {
3463                 syslog(LOG_ERR, "control socket: Couldn't bind to any socket");
3464                 free(socks);
3465                 return NULL;
3466         }
3467         return(socks);
3468 }