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. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 #if 0
  31 #ifndef lint
  32 static char copyright[] =
  33 "@(#) Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994\n\
  34         The Regents of the University of California.  All rights reserved.\n";
  35 #endif /* not lint */
  36 #endif
  37
  38 #ifndef lint
  39 #if 0
  40 static char sccsid[] = "@(#)ftpd.c      8.4 (Berkeley) 4/16/94";
  41 #endif
  42 #endif /* not lint */
  43
  44 #include <sys/cdefs.h>
  45 __FBSDID("$FreeBSD$");
  46
  47 /*
  48  * FTP server.
  49  */
  50 #include <sys/param.h>
  51 #include <sys/ioctl.h>
  52 #include <sys/mman.h>
  53 #include <sys/socket.h>
  54 #include <sys/stat.h>
  55 #include <sys/time.h>
  56 #include <sys/wait.h>
  57
  58 #include <netinet/in.h>
  59 #include <netinet/in_systm.h>
  60 #include <netinet/ip.h>
  61 #include <netinet/tcp.h>
  62
  63 #define FTP_NAMES
  64 #include <arpa/ftp.h>
  65 #include <arpa/inet.h>
  66 #include <arpa/telnet.h>
  67
  68 #include <ctype.h>
  69 #include <dirent.h>
  70 #include <err.h>
  71 #include <errno.h>
  72 #include <fcntl.h>
  73 #include <glob.h>
  74 #include <limits.h>
  75 #include <netdb.h>
  76 #include <pwd.h>
  77 #include <grp.h>
  78 #include <opie.h>
  79 #include <signal.h>
  80 #include <stdint.h>
  81 #include <stdio.h>
  82 #include <stdlib.h>
  83 #include <string.h>
  84 #include <syslog.h>
  85 #include <time.h>
  86 #include <unistd.h>
  87 #include <libutil.h>
  88 #ifdef  LOGIN_CAP
  89 #include <login_cap.h>
  90 #endif
  91
  92 #ifdef USE_PAM
  93 #include <security/pam_appl.h>
  94 #endif
  95
  96 #ifdef USE_BLACKLIST
  97 #include "blacklist_client.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     wtmpid[20];
 177
 178 #ifdef USE_PAM
 179 static int      auth_pam(struct passwd**, const char*);
 180 pam_handle_t    *pamh = NULL;
 181 #endif
 182
 183 static struct opie      opiedata;
 184 static char             opieprompt[OPIE_CHALLENGE_MAX+1];
 185 static int              pwok;
 186
 187 char    *pid_file = NULL; /* means default location to pidfile(3) */
 188
 189 /*
 190  * Limit number of pathnames that glob can return.
 191  * A limit of 0 indicates the number of pathnames is unlimited.
 192  */
 193 #define MAXGLOBARGS     16384
 194 #
 195
 196 /*
 197  * Timeout intervals for retrying connections
 198  * to hosts that don't accept PORT cmds.  This
 199  * is a kludge, but given the problems with TCP...
 200  */
 201 #define SWAITMAX        90      /* wait at most 90 seconds */
 202 #define SWAITINT        5       /* interval between retries */
 203
 204 int     swaitmax = SWAITMAX;
 205 int     swaitint = SWAITINT;
 206
 207 #ifdef SETPROCTITLE
 208 #ifdef OLD_SETPROCTITLE
 209 char    **Argv = NULL;          /* pointer to argument vector */
 210 char    *LastArgv = NULL;       /* end of argv */
 211 #endif /* OLD_SETPROCTITLE */
 212 char    proctitle[LINE_MAX];    /* initial part of title */
 213 #endif /* SETPROCTITLE */
 214
 215 #define LOGCMD(cmd, file)               logcmd((cmd), (file), NULL, -1)
 216 #define LOGCMD2(cmd, file1, file2)      logcmd((cmd), (file1), (file2), -1)
 217 #define LOGBYTES(cmd, file, cnt)        logcmd((cmd), (file), NULL, (cnt))
 218
 219 static  volatile sig_atomic_t recvurg;
 220 static  int transflag;          /* NB: for debugging only */
 221
 222 #define STARTXFER       flagxfer(1)
 223 #define ENDXFER         flagxfer(0)
 224
 225 #define START_UNSAFE    maskurg(1)
 226 #define END_UNSAFE      maskurg(0)
 227
 228 /* It's OK to put an `else' clause after this macro. */
 229 #define CHECKOOB(action)                                                \
 230         if (recvurg) {                                                  \
 231                 recvurg = 0;                                            \
 232                 if (myoob()) {                                          \
 233                         ENDXFER;                                        \
 234                         action;                                         \
 235                 }                                                       \
 236         }
 237
 238 #ifdef VIRTUAL_HOSTING
 239 static void      inithosts(int);
 240 static void      selecthost(union sockunion *);
 241 #endif
 242 static void      ack(char *);
 243 static void      sigurg(int);
 244 static void      maskurg(int);
 245 static void      flagxfer(int);
 246 static int       myoob(void);
 247 static int       checkuser(char *, char *, int, char **, int *);
 248 static FILE     *dataconn(char *, off_t, char *);
 249 static void      dolog(struct sockaddr *);
 250 static void      end_login(void);
 251 static FILE     *getdatasock(char *);
 252 static int       guniquefd(char *, char **);
 253 static void      lostconn(int);
 254 static void      sigquit(int);
 255 static int       receive_data(FILE *, FILE *);
 256 static int       send_data(FILE *, FILE *, size_t, off_t, int);
 257 static struct passwd *
 258                  sgetpwnam(char *);
 259 static char     *sgetsave(char *);
 260 static void      reapchild(int);
 261 static void      appendf(char **, char *, ...) __printflike(2, 3);
 262 static void      logcmd(char *, char *, char *, off_t);
 263 static void      logxfer(char *, off_t, time_t);
 264 static char     *doublequote(char *);
 265 static int      *socksetup(int, char *, const char *);
 266
 267 int
 268 main(int argc, char *argv[], char **envp)
 269 {
 270         socklen_t addrlen;
 271         int ch, on = 1, tos, s = STDIN_FILENO;
 272         char *cp, line[LINE_MAX];
 273         FILE *fd;
 274         char    *bindname = NULL;
 275         const char *bindport = "ftp";
 276         int     family = AF_UNSPEC;
 277         struct sigaction sa;
 278
 279         tzset();                /* in case no timezone database in ~ftp */
 280         sigemptyset(&sa.sa_mask);
 281         sa.sa_flags = SA_RESTART;
 282
 283 #ifdef OLD_SETPROCTITLE
 284         /*
 285          *  Save start and extent of argv for setproctitle.
 286          */
 287         Argv = argv;
 288         while (*envp)
 289                 envp++;
 290         LastArgv = envp[-1] + strlen(envp[-1]);
 291 #endif /* OLD_SETPROCTITLE */
 292
 293         /*
 294          * Prevent diagnostic messages from appearing on stderr.
 295          * We run as a daemon or from inetd; in both cases, there's
 296          * more reason in logging to syslog.
 297          */
 298         (void) freopen(_PATH_DEVNULL, "w", stderr);
 299         opterr = 0;
 300
 301         /*
 302          * LOG_NDELAY sets up the logging connection immediately,
 303          * necessary for anonymous ftp's that chroot and can't do it later.
 304          */
 305         openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP);
 306
 307         while ((ch = getopt(argc, argv,
 308                             "468a:AdDEhlmMoOp:P:rRSt:T:u:UvW")) != -1) {
 309                 switch (ch) {
 310                 case '4':
 311                         family = (family == AF_INET6) ? AF_UNSPEC : AF_INET;
 312                         break;
 313
 314                 case '6':
 315                         family = (family == AF_INET) ? AF_UNSPEC : AF_INET6;
 316                         break;
 317
 318                 case '8':
 319                         assumeutf8 = 1;
 320                         break;
 321
 322                 case 'a':
 323                         bindname = optarg;
 324                         break;
 325
 326                 case 'A':
 327                         anon_only = 1;
 328                         break;
 329
 330                 case 'd':
 331                         ftpdebug++;
 332                         break;
 333
 334                 case 'D':
 335                         daemon_mode++;
 336                         break;
 337
 338                 case 'E':
 339                         noepsv = 1;
 340                         break;
 341
 342                 case 'h':
 343                         hostinfo = 0;
 344                         break;
 345
 346                 case 'l':
 347                         logging++;      /* > 1 == extra logging */
 348                         break;
 349
 350                 case 'm':
 351                         noguestmod = 0;
 352                         break;
 353
 354                 case 'M':
 355                         noguestmkd = 1;
 356                         break;
 357
 358                 case 'o':
 359                         noretr = 1;
 360                         break;
 361
 362                 case 'O':
 363                         noguestretr = 1;
 364                         break;
 365
 366                 case 'p':
 367                         pid_file = optarg;
 368                         break;
 369
 370                 case 'P':
 371                         bindport = optarg;
 372                         break;
 373
 374                 case 'r':
 375                         readonly = 1;
 376                         break;
 377
 378                 case 'R':
 379                         paranoid = 0;
 380                         break;
 381
 382                 case 'S':
 383                         stats++;
 384                         break;
 385
 386                 case 't':
 387                         timeout = atoi(optarg);
 388                         if (maxtimeout < timeout)
 389                                 maxtimeout = timeout;
 390                         break;
 391
 392                 case 'T':
 393                         maxtimeout = atoi(optarg);
 394                         if (timeout > maxtimeout)
 395                                 timeout = maxtimeout;
 396                         break;
 397
 398                 case 'u':
 399                     {
 400                         long val = 0;
 401
 402                         val = strtol(optarg, &optarg, 8);
 403                         if (*optarg != '\0' || val < 0)
 404                                 syslog(LOG_WARNING, "bad value for -u");
 405                         else
 406                                 defumask = val;
 407                         break;
 408                     }
 409                 case 'U':
 410                         restricted_data_ports = 0;
 411                         break;
 412
 413                 case 'v':
 414                         ftpdebug++;
 415                         break;
 416
 417                 case 'W':
 418                         dowtmp = 0;
 419                         break;
 420
 421                 default:
 422                         syslog(LOG_WARNING, "unknown flag -%c ignored", optopt);
 423                         break;
 424                 }
 425         }
 426
 427         if (daemon_mode) {
 428                 int *ctl_sock, fd, maxfd = -1, nfds, i;
 429                 fd_set defreadfds, readfds;
 430                 pid_t pid;
 431                 struct pidfh *pfh;
 432
 433                 if ((pfh = pidfile_open(pid_file, 0600, &pid)) == NULL) {
 434                         if (errno == EEXIST) {
 435                                 syslog(LOG_ERR, "%s already running, pid %d",
 436                                        getprogname(), (int)pid);
 437                                 exit(1);
 438                         }
 439                         syslog(LOG_WARNING, "pidfile_open: %m");
 440                 }
 441
 442                 /*
 443                  * Detach from parent.
 444                  */
 445                 if (daemon(1, 1) < 0) {
 446                         syslog(LOG_ERR, "failed to become a daemon");
 447                         exit(1);
 448                 }
 449
 450                 if (pfh != NULL && pidfile_write(pfh) == -1)
 451                         syslog(LOG_WARNING, "pidfile_write: %m");
 452
 453                 sa.sa_handler = reapchild;
 454                 (void)sigaction(SIGCHLD, &sa, NULL);
 455
 456 #ifdef VIRTUAL_HOSTING
 457                 inithosts(family);
 458 #endif
 459
 460                 /*
 461                  * Open a socket, bind it to the FTP port, and start
 462                  * listening.
 463                  */
 464                 ctl_sock = socksetup(family, bindname, bindport);
 465                 if (ctl_sock == NULL)
 466                         exit(1);
 467
 468                 FD_ZERO(&defreadfds);
 469                 for (i = 1; i <= *ctl_sock; i++) {
 470                         FD_SET(ctl_sock[i], &defreadfds);
 471                         if (listen(ctl_sock[i], 32) < 0) {
 472                                 syslog(LOG_ERR, "control listen: %m");
 473                                 exit(1);
 474                         }
 475                         if (maxfd < ctl_sock[i])
 476                                 maxfd = ctl_sock[i];
 477                 }
 478
 479                 /*
 480                  * Loop forever accepting connection requests and forking off
 481                  * children to handle them.
 482                  */
 483                 while (1) {
 484                         FD_COPY(&defreadfds, &readfds);
 485                         nfds = select(maxfd + 1, &readfds, NULL, NULL, 0);
 486                         if (nfds <= 0) {
 487                                 if (nfds < 0 && errno != EINTR)
 488                                         syslog(LOG_WARNING, "select: %m");
 489                                 continue;
 490                         }
 491
 492                         pid = -1;
 493                         for (i = 1; i <= *ctl_sock; i++)
 494                                 if (FD_ISSET(ctl_sock[i], &readfds)) {
 495                                         addrlen = sizeof(his_addr);
 496                                         fd = accept(ctl_sock[i],
 497                                             (struct sockaddr *)&his_addr,
 498                                             &addrlen);
 499                                         if (fd == -1) {
 500                                                 syslog(LOG_WARNING,
 501                                                        "accept: %m");
 502                                                 continue;
 503                                         }
 504                                         switch (pid = fork()) {
 505                                         case 0:
 506                                                 /* child */
 507                                                 (void) dup2(fd, s);
 508                                                 (void) dup2(fd, STDOUT_FILENO);
 509                                                 (void) close(fd);
 510                                                 for (i = 1; i <= *ctl_sock; i++)
 511                                                         close(ctl_sock[i]);
 512                                                 if (pfh != NULL)
 513                                                         pidfile_close(pfh);
 514                                                 goto gotchild;
 515                                         case -1:
 516                                                 syslog(LOG_WARNING, "fork: %m");
 517                                                 /* FALLTHROUGH */
 518                                         default:
 519                                                 close(fd);
 520                                         }
 521                                 }
 522                 }
 523         } else {
 524                 addrlen = sizeof(his_addr);
 525                 if (getpeername(s, (struct sockaddr *)&his_addr, &addrlen) < 0) {
 526                         syslog(LOG_ERR, "getpeername (%s): %m",argv[0]);
 527                         exit(1);
 528                 }
 529
 530 #ifdef VIRTUAL_HOSTING
 531                 if (his_addr.su_family == AF_INET6 &&
 532                     IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr))
 533                         family = AF_INET;
 534                 else
 535                         family = his_addr.su_family;
 536                 inithosts(family);
 537 #endif
 538         }
 539
 540 gotchild:
 541         sa.sa_handler = SIG_DFL;
 542         (void)sigaction(SIGCHLD, &sa, NULL);
 543
 544         sa.sa_handler = sigurg;
 545         sa.sa_flags = 0;                /* don't restart syscalls for SIGURG */
 546         (void)sigaction(SIGURG, &sa, NULL);
 547
 548         sigfillset(&sa.sa_mask);        /* block all signals in handler */
 549         sa.sa_flags = SA_RESTART;
 550         sa.sa_handler = sigquit;
 551         (void)sigaction(SIGHUP, &sa, NULL);
 552         (void)sigaction(SIGINT, &sa, NULL);
 553         (void)sigaction(SIGQUIT, &sa, NULL);
 554         (void)sigaction(SIGTERM, &sa, NULL);
 555
 556         sa.sa_handler = lostconn;
 557         (void)sigaction(SIGPIPE, &sa, NULL);
 558
 559         addrlen = sizeof(ctrl_addr);
 560         if (getsockname(s, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) {
 561                 syslog(LOG_ERR, "getsockname (%s): %m",argv[0]);
 562                 exit(1);
 563         }
 564         dataport = ntohs(ctrl_addr.su_port) - 1; /* as per RFC 959 */
 565 #ifdef VIRTUAL_HOSTING
 566         /* select our identity from virtual host table */
 567         selecthost(&ctrl_addr);
 568 #endif
 569 #ifdef IP_TOS
 570         if (ctrl_addr.su_family == AF_INET)
 571       {
 572         tos = IPTOS_LOWDELAY;
 573         if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
 574                 syslog(LOG_WARNING, "control setsockopt (IP_TOS): %m");
 575       }
 576 #endif
 577         /*
 578          * Disable Nagle on the control channel so that we don't have to wait
 579          * for peer's ACK before issuing our next reply.
 580          */
 581         if (setsockopt(s, IPPROTO_TCP, TCP_NODELAY, &on, sizeof(on)) < 0)
 582                 syslog(LOG_WARNING, "control setsockopt (TCP_NODELAY): %m");
 583
 584         data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1);
 585
 586         (void)snprintf(wtmpid, sizeof(wtmpid), "%xftpd", getpid());
 587
 588         /* Try to handle urgent data inline */
 589 #ifdef SO_OOBINLINE
 590         if (setsockopt(s, SOL_SOCKET, SO_OOBINLINE, &on, sizeof(on)) < 0)
 591                 syslog(LOG_WARNING, "control setsockopt (SO_OOBINLINE): %m");
 592 #endif
 593
 594 #ifdef  F_SETOWN
 595         if (fcntl(s, F_SETOWN, getpid()) == -1)
 596                 syslog(LOG_ERR, "fcntl F_SETOWN: %m");
 597 #endif
 598         dolog((struct sockaddr *)&his_addr);
 599         /*
 600          * Set up default state
 601          */
 602         data = -1;
 603         type = TYPE_A;
 604         form = FORM_N;
 605         stru = STRU_F;
 606         mode = MODE_S;
 607         tmpline[0] = '\0';
 608
 609         /* If logins are disabled, print out the message. */
 610         if ((fd = fopen(_PATH_NOLOGIN,"r")) != NULL) {
 611                 while (fgets(line, sizeof(line), fd) != NULL) {
 612                         if ((cp = strchr(line, '\n')) != NULL)
 613                                 *cp = '\0';
 614                         lreply(530, "%s", line);
 615                 }
 616                 (void) fflush(stdout);
 617                 (void) fclose(fd);
 618                 reply(530, "System not available.");
 619                 exit(0);
 620         }
 621 #ifdef VIRTUAL_HOSTING
 622         fd = fopen(thishost->welcome, "r");
 623 #else
 624         fd = fopen(_PATH_FTPWELCOME, "r");
 625 #endif
 626         if (fd != NULL) {
 627                 while (fgets(line, sizeof(line), fd) != NULL) {
 628                         if ((cp = strchr(line, '\n')) != NULL)
 629                                 *cp = '\0';
 630                         lreply(220, "%s", line);
 631                 }
 632                 (void) fflush(stdout);
 633                 (void) fclose(fd);
 634                 /* reply(220,) must follow */
 635         }
 636 #ifndef VIRTUAL_HOSTING
 637         if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
 638                 fatalerror("Ran out of memory.");
 639         if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
 640                 hostname[0] = '\0';
 641         hostname[MAXHOSTNAMELEN - 1] = '\0';
 642 #endif
 643         if (hostinfo)
 644                 reply(220, "%s FTP server (%s) ready.", hostname, version);
 645         else
 646                 reply(220, "FTP server ready.");
 647 #ifdef USE_BLACKLIST
 648         blacklist_init();
 649 #endif
 650         for (;;)
 651                 (void) yyparse();
 652         /* NOTREACHED */
 653 }
 654
 655 static void
 656 lostconn(int signo)
 657 {
 658
 659         if (ftpdebug)
 660                 syslog(LOG_DEBUG, "lost connection");
 661         dologout(1);
 662 }
 663
 664 static void
 665 sigquit(int signo)
 666 {
 667
 668         syslog(LOG_ERR, "got signal %d", signo);
 669         dologout(1);
 670 }
 671
 672 #ifdef VIRTUAL_HOSTING
 673 /*
 674  * read in virtual host tables (if they exist)
 675  */
 676
 677 static void
 678 inithosts(int family)
 679 {
 680         int insert;
 681         size_t len;
 682         FILE *fp;
 683         char *cp, *mp, *line;
 684         char *hostname;
 685         char *vhost, *anonuser, *statfile, *welcome, *loginmsg;
 686         struct ftphost *hrp, *lhrp;
 687         struct addrinfo hints, *res, *ai;
 688
 689         /*
 690          * Fill in the default host information
 691          */
 692         if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
 693                 fatalerror("Ran out of memory.");
 694         if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
 695                 hostname[0] = '\0';
 696         hostname[MAXHOSTNAMELEN - 1] = '\0';
 697         if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
 698                 fatalerror("Ran out of memory.");
 699         hrp->hostname = hostname;
 700         hrp->hostinfo = NULL;
 701
 702         memset(&hints, 0, sizeof(hints));
 703         hints.ai_flags = AI_PASSIVE;
 704         hints.ai_family = family;
 705         hints.ai_socktype = SOCK_STREAM;
 706         if (getaddrinfo(hrp->hostname, NULL, &hints, &res) == 0)
 707                 hrp->hostinfo = res;
 708         hrp->statfile = _PATH_FTPDSTATFILE;
 709         hrp->welcome  = _PATH_FTPWELCOME;
 710         hrp->loginmsg = _PATH_FTPLOGINMESG;
 711         hrp->anonuser = "ftp";
 712         hrp->next = NULL;
 713         thishost = firsthost = lhrp = hrp;
 714         if ((fp = fopen(_PATH_FTPHOSTS, "r")) != NULL) {
 715                 int addrsize, gothost;
 716                 void *addr;
 717                 struct hostent *hp;
 718
 719                 while ((line = fgetln(fp, &len)) != NULL) {
 720                         int     i, hp_error;
 721
 722                         /* skip comments */
 723                         if (line[0] == '#')
 724                                 continue;
 725                         if (line[len - 1] == '\n') {
 726                                 line[len - 1] = '\0';
 727                                 mp = NULL;
 728                         } else {
 729                                 if ((mp = malloc(len + 1)) == NULL)
 730                                         fatalerror("Ran out of memory.");
 731                                 memcpy(mp, line, len);
 732                                 mp[len] = '\0';
 733                                 line = mp;
 734                         }
 735                         cp = strtok(line, " \t");
 736                         /* skip empty lines */
 737                         if (cp == NULL)
 738                                 goto nextline;
 739                         vhost = cp;
 740
 741                         /* set defaults */
 742                         anonuser = "ftp";
 743                         statfile = _PATH_FTPDSTATFILE;
 744                         welcome  = _PATH_FTPWELCOME;
 745                         loginmsg = _PATH_FTPLOGINMESG;
 746
 747                         /*
 748                          * Preparse the line so we can use its info
 749                          * for all the addresses associated with
 750                          * the virtual host name.
 751                          * Field 0, the virtual host name, is special:
 752                          * it's already parsed off and will be strdup'ed
 753                          * later, after we know its canonical form.
 754                          */
 755                         for (i = 1; i < 5 && (cp = strtok(NULL, " \t")); i++)
 756                                 if (*cp != '-' && (cp = strdup(cp)))
 757                                         switch (i) {
 758                                         case 1: /* anon user permissions */
 759                                                 anonuser = cp;
 760                                                 break;
 761                                         case 2: /* statistics file */
 762                                                 statfile = cp;
 763                                                 break;
 764                                         case 3: /* welcome message */
 765                                                 welcome  = cp;
 766                                                 break;
 767                                         case 4: /* login message */
 768                                                 loginmsg = cp;
 769                                                 break;
 770                                         default: /* programming error */
 771                                                 abort();
 772                                                 /* NOTREACHED */
 773                                         }
 774
 775                         hints.ai_flags = AI_PASSIVE;
 776                         hints.ai_family = family;
 777                         hints.ai_socktype = SOCK_STREAM;
 778                         if (getaddrinfo(vhost, NULL, &hints, &res) != 0)
 779                                 goto nextline;
 780                         for (ai = res; ai != NULL && ai->ai_addr != NULL;
 781                              ai = ai->ai_next) {
 782
 783                         gothost = 0;
 784                         for (hrp = firsthost; hrp != NULL; hrp = hrp->next) {
 785                                 struct addrinfo *hi;
 786
 787                                 for (hi = hrp->hostinfo; hi != NULL;
 788                                      hi = hi->ai_next)
 789                                         if (hi->ai_addrlen == ai->ai_addrlen &&
 790                                             memcmp(hi->ai_addr,
 791                                                    ai->ai_addr,
 792                                                    ai->ai_addr->sa_len) == 0) {
 793                                                 gothost++;
 794                                                 break;
 795                                         }
 796                                 if (gothost)
 797                                         break;
 798                         }
 799                         if (hrp == NULL) {
 800                                 if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
 801                                         goto nextline;
 802                                 hrp->hostname = NULL;
 803                                 insert = 1;
 804                         } else {
 805                                 if (hrp->hostinfo && hrp->hostinfo != res)
 806                                         freeaddrinfo(hrp->hostinfo);
 807                                 insert = 0; /* host already in the chain */
 808                         }
 809                         hrp->hostinfo = res;
 810
 811                         /*
 812                          * determine hostname to use.
 813                          * force defined name if there is a valid alias
 814                          * otherwise fallback to primary hostname
 815                          */
 816                         /* XXX: getaddrinfo() can't do alias check */
 817                         switch(hrp->hostinfo->ai_family) {
 818                         case AF_INET:
 819                                 addr = &((struct sockaddr_in *)hrp->hostinfo->ai_addr)->sin_addr;
 820                                 addrsize = sizeof(struct in_addr);
 821                                 break;
 822                         case AF_INET6:
 823                                 addr = &((struct sockaddr_in6 *)hrp->hostinfo->ai_addr)->sin6_addr;
 824                                 addrsize = sizeof(struct in6_addr);
 825                                 break;
 826                         default:
 827                                 /* should not reach here */
 828                                 freeaddrinfo(hrp->hostinfo);
 829                                 if (insert)
 830                                         free(hrp); /*not in chain, can free*/
 831                                 else
 832                                         hrp->hostinfo = NULL; /*mark as blank*/
 833                                 goto nextline;
 834                                 /* NOTREACHED */
 835                         }
 836                         if ((hp = getipnodebyaddr(addr, addrsize,
 837                                                   hrp->hostinfo->ai_family,
 838                                                   &hp_error)) != NULL) {
 839                                 if (strcmp(vhost, hp->h_name) != 0) {
 840                                         if (hp->h_aliases == NULL)
 841                                                 vhost = hp->h_name;
 842                                         else {
 843                                                 i = 0;
 844                                                 while (hp->h_aliases[i] &&
 845                                                        strcmp(vhost, hp->h_aliases[i]) != 0)
 846                                                         ++i;
 847                                                 if (hp->h_aliases[i] == NULL)
 848                                                         vhost = hp->h_name;
 849                                         }
 850                                 }
 851                         }
 852                         if (hrp->hostname &&
 853                             strcmp(hrp->hostname, vhost) != 0) {
 854                                 free(hrp->hostname);
 855                                 hrp->hostname = NULL;
 856                         }
 857                         if (hrp->hostname == NULL &&
 858                             (hrp->hostname = strdup(vhost)) == NULL) {
 859                                 freeaddrinfo(hrp->hostinfo);
 860                                 hrp->hostinfo = NULL; /* mark as blank */
 861                                 if (hp)
 862                                         freehostent(hp);
 863                                 goto nextline;
 864                         }
 865                         hrp->anonuser = anonuser;
 866                         hrp->statfile = statfile;
 867                         hrp->welcome  = welcome;
 868                         hrp->loginmsg = loginmsg;
 869                         if (insert) {
 870                                 hrp->next  = NULL;
 871                                 lhrp->next = hrp;
 872                                 lhrp = hrp;
 873                         }
 874                         if (hp)
 875                                 freehostent(hp);
 876                       }
 877 nextline:
 878                         if (mp)
 879                                 free(mp);
 880                 }
 881                 (void) fclose(fp);
 882         }
 883 }
 884
 885 static void
 886 selecthost(union sockunion *su)
 887 {
 888         struct ftphost  *hrp;
 889         u_int16_t port;
 890 #ifdef INET6
 891         struct in6_addr *mapped_in6 = NULL;
 892 #endif
 893         struct addrinfo *hi;
 894
 895 #ifdef INET6
 896         /*
 897          * XXX IPv4 mapped IPv6 addr consideraton,
 898          * specified in rfc2373.
 899          */
 900         if (su->su_family == AF_INET6 &&
 901             IN6_IS_ADDR_V4MAPPED(&su->su_sin6.sin6_addr))
 902                 mapped_in6 = &su->su_sin6.sin6_addr;
 903 #endif
 904
 905         hrp = thishost = firsthost;     /* default */
 906         port = su->su_port;
 907         su->su_port = 0;
 908         while (hrp != NULL) {
 909             for (hi = hrp->hostinfo; hi != NULL; hi = hi->ai_next) {
 910                 if (memcmp(su, hi->ai_addr, hi->ai_addrlen) == 0) {
 911                         thishost = hrp;
 912                         goto found;
 913                 }
 914 #ifdef INET6
 915                 /* XXX IPv4 mapped IPv6 addr consideraton */
 916                 if (hi->ai_addr->sa_family == AF_INET && mapped_in6 != NULL &&
 917                     (memcmp(&mapped_in6->s6_addr[12],
 918                             &((struct sockaddr_in *)hi->ai_addr)->sin_addr,
 919                             sizeof(struct in_addr)) == 0)) {
 920                         thishost = hrp;
 921                         goto found;
 922                 }
 923 #endif
 924             }
 925             hrp = hrp->next;
 926         }
 927 found:
 928         su->su_port = port;
 929         /* setup static variables as appropriate */
 930         hostname = thishost->hostname;
 931         ftpuser = thishost->anonuser;
 932 }
 933 #endif
 934
 935 /*
 936  * Helper function for sgetpwnam().
 937  */
 938 static char *
 939 sgetsave(char *s)
 940 {
 941         char *new = malloc(strlen(s) + 1);
 942
 943         if (new == NULL) {
 944                 reply(421, "Ran out of memory.");
 945                 dologout(1);
 946                 /* NOTREACHED */
 947         }
 948         (void) strcpy(new, s);
 949         return (new);
 950 }
 951
 952 /*
 953  * Save the result of a getpwnam.  Used for USER command, since
 954  * the data returned must not be clobbered by any other command
 955  * (e.g., globbing).
 956  * NB: The data returned by sgetpwnam() will remain valid until
 957  * the next call to this function.  Its difference from getpwnam()
 958  * is that sgetpwnam() is known to be called from ftpd code only.
 959  */
 960 static struct passwd *
 961 sgetpwnam(char *name)
 962 {
 963         static struct passwd save;
 964         struct passwd *p;
 965
 966         if ((p = getpwnam(name)) == NULL)
 967                 return (p);
 968         if (save.pw_name) {
 969                 free(save.pw_name);
 970                 free(save.pw_passwd);
 971                 free(save.pw_class);
 972                 free(save.pw_gecos);
 973                 free(save.pw_dir);
 974                 free(save.pw_shell);
 975         }
 976         save = *p;
 977         save.pw_name = sgetsave(p->pw_name);
 978         save.pw_passwd = sgetsave(p->pw_passwd);
 979         save.pw_class = sgetsave(p->pw_class);
 980         save.pw_gecos = sgetsave(p->pw_gecos);
 981         save.pw_dir = sgetsave(p->pw_dir);
 982         save.pw_shell = sgetsave(p->pw_shell);
 983         return (&save);
 984 }
 985
 986 static int login_attempts;      /* number of failed login attempts */
 987 static int askpasswd;           /* had user command, ask for passwd */
 988 static char curname[MAXLOGNAME];        /* current USER name */
 989
 990 /*
 991  * USER command.
 992  * Sets global passwd pointer pw if named account exists and is acceptable;
 993  * sets askpasswd if a PASS command is expected.  If logged in previously,
 994  * need to reset state.  If name is "ftp" or "anonymous", the name is not in
 995  * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return.
 996  * If account doesn't exist, ask for passwd anyway.  Otherwise, check user
 997  * requesting login privileges.  Disallow anyone who does not have a standard
 998  * shell as returned by getusershell().  Disallow anyone mentioned in the file
 999  * _PATH_FTPUSERS to allow people such as root and uucp to be avoided.
1000  */
1001 void
1002 user(char *name)
1003 {
1004         int ecode;
1005         char *cp, *shell;
1006
1007         if (logged_in) {
1008                 if (guest) {
1009                         reply(530, "Can't change user from guest login.");
1010                         return;
1011                 } else if (dochroot) {
1012                         reply(530, "Can't change user from chroot user.");
1013                         return;
1014                 }
1015                 end_login();
1016         }
1017
1018         guest = 0;
1019 #ifdef VIRTUAL_HOSTING
1020         pw = sgetpwnam(thishost->anonuser);
1021 #else
1022         pw = sgetpwnam("ftp");
1023 #endif
1024         if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) {
1025                 if (checkuser(_PATH_FTPUSERS, "ftp", 0, NULL, &ecode) ||
1026                     (ecode != 0 && ecode != ENOENT))
1027                         reply(530, "User %s access denied.", name);
1028                 else if (checkuser(_PATH_FTPUSERS, "anonymous", 0, NULL, &ecode) ||
1029                     (ecode != 0 && ecode != ENOENT))
1030                         reply(530, "User %s access denied.", name);
1031                 else if (pw != NULL) {
1032                         guest = 1;
1033                         askpasswd = 1;
1034                         reply(331,
1035                         "Guest login ok, send your email address as password.");
1036                 } else
1037                         reply(530, "User %s unknown.", name);
1038                 if (!askpasswd && logging)
1039                         syslog(LOG_NOTICE,
1040                             "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost);
1041                 return;
1042         }
1043         if (anon_only != 0) {
1044                 reply(530, "Sorry, only anonymous ftp allowed.");
1045                 return;
1046         }
1047
1048         if ((pw = sgetpwnam(name))) {
1049                 if ((shell = pw->pw_shell) == NULL || *shell == 0)
1050                         shell = _PATH_BSHELL;
1051                 setusershell();
1052                 while ((cp = getusershell()) != NULL)
1053                         if (strcmp(cp, shell) == 0)
1054                                 break;
1055                 endusershell();
1056
1057                 if (cp == NULL ||
1058                     (checkuser(_PATH_FTPUSERS, name, 1, NULL, &ecode) ||
1059                     (ecode != 0 && ecode != ENOENT))) {
1060                         reply(530, "User %s access denied.", name);
1061                         if (logging)
1062                                 syslog(LOG_NOTICE,
1063                                     "FTP LOGIN REFUSED FROM %s, %s",
1064                                     remotehost, name);
1065                         pw = NULL;
1066                         return;
1067                 }
1068         }
1069         if (logging)
1070                 strncpy(curname, name, sizeof(curname)-1);
1071
1072         pwok = 0;
1073 #ifdef USE_PAM
1074         /* XXX Kluge! The conversation mechanism needs to be fixed. */
1075 #endif
1076         if (opiechallenge(&opiedata, name, opieprompt) == 0) {
1077                 pwok = (pw != NULL) &&
1078                        opieaccessfile(remotehost) &&
1079                        opiealways(pw->pw_dir);
1080                 reply(331, "Response to %s %s for %s.",
1081                       opieprompt, pwok ? "requested" : "required", name);
1082         } else {
1083                 pwok = 1;
1084                 reply(331, "Password required for %s.", name);
1085         }
1086         askpasswd = 1;
1087         /*
1088          * Delay before reading passwd after first failed
1089          * attempt to slow down passwd-guessing programs.
1090          */
1091         if (login_attempts)
1092                 sleep(login_attempts);
1093 }
1094
1095 /*
1096  * Check if a user is in the file "fname",
1097  * return a pointer to a malloc'd string with the rest
1098  * of the matching line in "residue" if not NULL.
1099  */
1100 static int
1101 checkuser(char *fname, char *name, int pwset, char **residue, int *ecode)
1102 {
1103         FILE *fd;
1104         int found = 0;
1105         size_t len;
1106         char *line, *mp, *p;
1107
1108         if (ecode != NULL)
1109                 *ecode = 0;
1110         if ((fd = fopen(fname, "r")) != NULL) {
1111                 while (!found && (line = fgetln(fd, &len)) != NULL) {
1112                         /* skip comments */
1113                         if (line[0] == '#')
1114                                 continue;
1115                         if (line[len - 1] == '\n') {
1116                                 line[len - 1] = '\0';
1117                                 mp = NULL;
1118                         } else {
1119                                 if ((mp = malloc(len + 1)) == NULL)
1120                                         fatalerror("Ran out of memory.");
1121                                 memcpy(mp, line, len);
1122                                 mp[len] = '\0';
1123                                 line = mp;
1124                         }
1125                         /* avoid possible leading and trailing whitespace */
1126                         p = strtok(line, " \t");
1127                         /* skip empty lines */
1128                         if (p == NULL)
1129                                 goto nextline;
1130                         /*
1131                          * if first chr is '@', check group membership
1132                          */
1133                         if (p[0] == '@') {
1134                                 int i = 0;
1135                                 struct group *grp;
1136
1137                                 if (p[1] == '\0') /* single @ matches anyone */
1138                                         found = 1;
1139                                 else {
1140                                         if ((grp = getgrnam(p+1)) == NULL)
1141                                                 goto nextline;
1142                                         /*
1143                                          * Check user's default group
1144                                          */
1145                                         if (pwset && grp->gr_gid == pw->pw_gid)
1146                                                 found = 1;
1147                                         /*
1148                                          * Check supplementary groups
1149                                          */
1150                                         while (!found && grp->gr_mem[i])
1151                                                 found = strcmp(name,
1152                                                         grp->gr_mem[i++])
1153                                                         == 0;
1154                                 }
1155                         }
1156                         /*
1157                          * Otherwise, just check for username match
1158                          */
1159                         else
1160                                 found = strcmp(p, name) == 0;
1161                         /*
1162                          * Save the rest of line to "residue" if matched
1163                          */
1164                         if (found && residue) {
1165                                 if ((p = strtok(NULL, "")) != NULL)
1166                                         p += strspn(p, " \t");
1167                                 if (p && *p) {
1168                                         if ((*residue = strdup(p)) == NULL)
1169                                                 fatalerror("Ran out of memory.");
1170                                 } else
1171                                         *residue = NULL;
1172                         }
1173 nextline:
1174                         if (mp)
1175                                 free(mp);
1176                 }
1177                 (void) fclose(fd);
1178         } else if (ecode != NULL)
1179                 *ecode = errno;
1180         return (found);
1181 }
1182
1183 /*
1184  * Terminate login as previous user, if any, resetting state;
1185  * used when USER command is given or login fails.
1186  */
1187 static void
1188 end_login(void)
1189 {
1190 #ifdef USE_PAM
1191         int e;
1192 #endif
1193
1194         (void) seteuid(0);
1195         if (logged_in && dowtmp)
1196                 ftpd_logwtmp(wtmpid, NULL, NULL);
1197         pw = NULL;
1198 #ifdef  LOGIN_CAP
1199         setusercontext(NULL, getpwuid(0), 0, LOGIN_SETALL & ~(LOGIN_SETLOGIN |
1200                        LOGIN_SETUSER | LOGIN_SETGROUP | LOGIN_SETPATH |
1201                        LOGIN_SETENV));
1202 #endif
1203 #ifdef USE_PAM
1204         if (pamh) {
1205                 if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS)
1206                         syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1207                 if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS)
1208                         syslog(LOG_ERR, "pam_close_session: %s", pam_strerror(pamh, e));
1209                 if ((e = pam_end(pamh, e)) != PAM_SUCCESS)
1210                         syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1211                 pamh = NULL;
1212         }
1213 #endif
1214         logged_in = 0;
1215         guest = 0;
1216         dochroot = 0;
1217 }
1218
1219 #ifdef USE_PAM
1220
1221 /*
1222  * the following code is stolen from imap-uw PAM authentication module and
1223  * login.c
1224  */
1225 #define COPY_STRING(s) (s ? strdup(s) : NULL)
1226
1227 struct cred_t {
1228         const char *uname;              /* user name */
1229         const char *pass;               /* password */
1230 };
1231 typedef struct cred_t cred_t;
1232
1233 static int
1234 auth_conv(int num_msg, const struct pam_message **msg,
1235           struct pam_response **resp, void *appdata)
1236 {
1237         int i;
1238         cred_t *cred = (cred_t *) appdata;
1239         struct pam_response *reply;
1240
1241         reply = calloc(num_msg, sizeof *reply);
1242         if (reply == NULL)
1243                 return PAM_BUF_ERR;
1244
1245         for (i = 0; i < num_msg; i++) {
1246                 switch (msg[i]->msg_style) {
1247                 case PAM_PROMPT_ECHO_ON:        /* assume want user name */
1248                         reply[i].resp_retcode = PAM_SUCCESS;
1249                         reply[i].resp = COPY_STRING(cred->uname);
1250                         /* PAM frees resp. */
1251                         break;
1252                 case PAM_PROMPT_ECHO_OFF:       /* assume want password */
1253                         reply[i].resp_retcode = PAM_SUCCESS;
1254                         reply[i].resp = COPY_STRING(cred->pass);
1255                         /* PAM frees resp. */
1256                         break;
1257                 case PAM_TEXT_INFO:
1258                 case PAM_ERROR_MSG:
1259                         reply[i].resp_retcode = PAM_SUCCESS;
1260                         reply[i].resp = NULL;
1261                         break;
1262                 default:                        /* unknown message style */
1263                         free(reply);
1264                         return PAM_CONV_ERR;
1265                 }
1266         }
1267
1268         *resp = reply;
1269         return PAM_SUCCESS;
1270 }
1271
1272 /*
1273  * Attempt to authenticate the user using PAM.  Returns 0 if the user is
1274  * authenticated, or 1 if not authenticated.  If some sort of PAM system
1275  * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
1276  * function returns -1.  This can be used as an indication that we should
1277  * fall back to a different authentication mechanism.
1278  */
1279 static int
1280 auth_pam(struct passwd **ppw, const char *pass)
1281 {
1282         const char *tmpl_user;
1283         const void *item;
1284         int rval;
1285         int e;
1286         cred_t auth_cred = { (*ppw)->pw_name, pass };
1287         struct pam_conv conv = { &auth_conv, &auth_cred };
1288
1289         e = pam_start("ftpd", (*ppw)->pw_name, &conv, &pamh);
1290         if (e != PAM_SUCCESS) {
1291                 /*
1292                  * In OpenPAM, it's OK to pass NULL to pam_strerror()
1293                  * if context creation has failed in the first place.
1294                  */
1295                 syslog(LOG_ERR, "pam_start: %s", pam_strerror(NULL, e));
1296                 return -1;
1297         }
1298
1299         e = pam_set_item(pamh, PAM_RHOST, remotehost);
1300         if (e != PAM_SUCCESS) {
1301                 syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
1302                         pam_strerror(pamh, e));
1303                 if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1304                         syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1305                 }
1306                 pamh = NULL;
1307                 return -1;
1308         }
1309
1310         e = pam_authenticate(pamh, 0);
1311         switch (e) {
1312         case PAM_SUCCESS:
1313                 /*
1314                  * With PAM we support the concept of a "template"
1315                  * user.  The user enters a login name which is
1316                  * authenticated by PAM, usually via a remote service
1317                  * such as RADIUS or TACACS+.  If authentication
1318                  * succeeds, a different but related "template" name
1319                  * is used for setting the credentials, shell, and
1320                  * home directory.  The name the user enters need only
1321                  * exist on the remote authentication server, but the
1322                  * template name must be present in the local password
1323                  * database.
1324                  *
1325                  * This is supported by two various mechanisms in the
1326                  * individual modules.  However, from the application's
1327                  * point of view, the template user is always passed
1328                  * back as a changed value of the PAM_USER item.
1329                  */
1330                 if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
1331                     PAM_SUCCESS) {
1332                         tmpl_user = (const char *) item;
1333                         if (strcmp((*ppw)->pw_name, tmpl_user) != 0)
1334                                 *ppw = getpwnam(tmpl_user);
1335                 } else
1336                         syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
1337                             pam_strerror(pamh, e));
1338                 rval = 0;
1339                 break;
1340
1341         case PAM_AUTH_ERR:
1342         case PAM_USER_UNKNOWN:
1343         case PAM_MAXTRIES:
1344                 rval = 1;
1345                 break;
1346
1347         default:
1348                 syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
1349                 rval = -1;
1350                 break;
1351         }
1352
1353         if (rval == 0) {
1354                 e = pam_acct_mgmt(pamh, 0);
1355                 if (e != PAM_SUCCESS) {
1356                         syslog(LOG_ERR, "pam_acct_mgmt: %s",
1357                                                 pam_strerror(pamh, e));
1358                         rval = 1;
1359                 }
1360         }
1361
1362         if (rval != 0) {
1363                 if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1364                         syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1365                 }
1366                 pamh = NULL;
1367         }
1368         return rval;
1369 }
1370
1371 #endif /* USE_PAM */
1372
1373 void
1374 pass(char *passwd)
1375 {
1376         int rval, ecode;
1377         FILE *fd;
1378 #ifdef  LOGIN_CAP
1379         login_cap_t *lc = NULL;
1380 #endif
1381 #ifdef USE_PAM
1382         int e;
1383 #endif
1384         char *residue = NULL;
1385         char *xpasswd;
1386
1387         if (logged_in || askpasswd == 0) {
1388                 reply(503, "Login with USER first.");
1389                 return;
1390         }
1391         askpasswd = 0;
1392         if (!guest) {           /* "ftp" is only account allowed no password */
1393                 if (pw == NULL) {
1394                         rval = 1;       /* failure below */
1395                         goto skip;
1396                 }
1397 #ifdef USE_PAM
1398                 rval = auth_pam(&pw, passwd);
1399                 if (rval >= 0) {
1400                         opieunlock();
1401                         goto skip;
1402                 }
1403 #endif
1404                 if (opieverify(&opiedata, passwd) == 0)
1405                         xpasswd = pw->pw_passwd;
1406                 else if (pwok) {
1407                         xpasswd = crypt(passwd, pw->pw_passwd);
1408                         if (passwd[0] == '\0' && pw->pw_passwd[0] != '\0')
1409                                 xpasswd = ":";
1410                 } else {
1411                         rval = 1;
1412                         goto skip;
1413                 }
1414                 rval = strcmp(pw->pw_passwd, xpasswd);
1415                 if (pw->pw_expire && time(NULL) >= pw->pw_expire)
1416                         rval = 1;       /* failure */
1417 skip:
1418                 /*
1419                  * If rval == 1, the user failed the authentication check
1420                  * above.  If rval == 0, either PAM or local authentication
1421                  * succeeded.
1422                  */
1423                 if (rval) {
1424                         reply(530, "Login incorrect.");
1425 #ifdef USE_BLACKLIST
1426                         blacklist_notify(1, STDIN_FILENO, "Login incorrect");
1427 #endif
1428                         if (logging) {
1429                                 syslog(LOG_NOTICE,
1430                                     "FTP LOGIN FAILED FROM %s",
1431                                     remotehost);
1432                                 syslog(LOG_AUTHPRIV | LOG_NOTICE,
1433                                     "FTP LOGIN FAILED FROM %s, %s",
1434                                     remotehost, curname);
1435                         }
1436                         pw = NULL;
1437                         if (login_attempts++ >= 5) {
1438                                 syslog(LOG_NOTICE,
1439                                     "repeated login failures from %s",
1440                                     remotehost);
1441                                 exit(0);
1442                         }
1443                         return;
1444                 }
1445 #ifdef USE_BLACKLIST
1446                  else {
1447                         blacklist_notify(0, STDIN_FILENO, "Login successful");
1448                 }
1449 #endif
1450         }
1451         login_attempts = 0;             /* this time successful */
1452         if (setegid(pw->pw_gid) < 0) {
1453                 reply(550, "Can't set gid.");
1454                 return;
1455         }
1456         /* May be overridden by login.conf */
1457         (void) umask(defumask);
1458 #ifdef  LOGIN_CAP
1459         if ((lc = login_getpwclass(pw)) != NULL) {
1460                 char    remote_ip[NI_MAXHOST];
1461
1462                 if (getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
1463                         remote_ip, sizeof(remote_ip) - 1, NULL, 0,
1464                         NI_NUMERICHOST))
1465                                 *remote_ip = 0;
1466                 remote_ip[sizeof(remote_ip) - 1] = 0;
1467                 if (!auth_hostok(lc, remotehost, remote_ip)) {
1468                         syslog(LOG_INFO|LOG_AUTH,
1469                             "FTP LOGIN FAILED (HOST) as %s: permission denied.",
1470                             pw->pw_name);
1471                         reply(530, "Permission denied.");
1472                         pw = NULL;
1473                         return;
1474                 }
1475                 if (!auth_timeok(lc, time(NULL))) {
1476                         reply(530, "Login not available right now.");
1477                         pw = NULL;
1478                         return;
1479                 }
1480         }
1481         setusercontext(lc, pw, 0, LOGIN_SETALL &
1482                        ~(LOGIN_SETUSER | LOGIN_SETPATH | LOGIN_SETENV));
1483 #else
1484         setlogin(pw->pw_name);
1485         (void) initgroups(pw->pw_name, pw->pw_gid);
1486 #endif
1487
1488 #ifdef USE_PAM
1489         if (pamh) {
1490                 if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
1491                         syslog(LOG_ERR, "pam_open_session: %s", pam_strerror(pamh, e));
1492                 } else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED)) != PAM_SUCCESS) {
1493                         syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1494                 }
1495         }
1496 #endif
1497
1498         dochroot =
1499                 checkuser(_PATH_FTPCHROOT, pw->pw_name, 1, &residue, &ecode)
1500 #ifdef  LOGIN_CAP       /* Allow login.conf configuration as well */
1501                 || login_getcapbool(lc, "ftp-chroot", 0)
1502 #endif
1503         ;
1504         /*
1505          * It is possible that checkuser() failed to open the chroot file.
1506          * If this is the case, report that logins are un-available, since we
1507          * have no way of checking whether or not the user should be chrooted.
1508          * We ignore ENOENT since it is not required that this file be present.
1509          */
1510         if (ecode != 0 && ecode != ENOENT) {
1511                 reply(530, "Login not available right now.");
1512                 return;
1513         }
1514         chrootdir = NULL;
1515
1516         /* Disable wtmp logging when chrooting. */
1517         if (dochroot || guest)
1518                 dowtmp = 0;
1519         if (dowtmp)
1520                 ftpd_logwtmp(wtmpid, pw->pw_name,
1521                     (struct sockaddr *)&his_addr);
1522         logged_in = 1;
1523
1524         if (guest && stats && statfd < 0)
1525 #ifdef VIRTUAL_HOSTING
1526                 statfd = open(thishost->statfile, O_WRONLY|O_APPEND);
1527 #else
1528                 statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND);
1529 #endif
1530                 if (statfd < 0)
1531                         stats = 0;
1532
1533         /*
1534          * For a chrooted local user,
1535          * a) see whether ftpchroot(5) specifies a chroot directory,
1536          * b) extract the directory pathname from the line,
1537          * c) expand it to the absolute pathname if necessary.
1538          */
1539         if (dochroot && residue &&
1540             (chrootdir = strtok(residue, " \t")) != NULL) {
1541                 if (chrootdir[0] != '/')
1542                         asprintf(&chrootdir, "%s/%s", pw->pw_dir, chrootdir);
1543                 else
1544                         chrootdir = strdup(chrootdir); /* make it permanent */
1545                 if (chrootdir == NULL)
1546                         fatalerror("Ran out of memory.");
1547         }
1548         if (guest || dochroot) {
1549                 /*
1550                  * If no chroot directory set yet, use the login directory.
1551                  * Copy it so it can be modified while pw->pw_dir stays intact.
1552                  */
1553                 if (chrootdir == NULL &&
1554                     (chrootdir = strdup(pw->pw_dir)) == NULL)
1555                         fatalerror("Ran out of memory.");
1556                 /*
1557                  * Check for the "/chroot/./home" syntax,
1558                  * separate the chroot and home directory pathnames.
1559                  */
1560                 if ((homedir = strstr(chrootdir, "/./")) != NULL) {
1561                         *(homedir++) = '\0';    /* wipe '/' */
1562                         homedir++;              /* skip '.' */
1563                 } else {
1564                         /*
1565                          * We MUST do a chdir() after the chroot. Otherwise
1566                          * the old current directory will be accessible as "."
1567                          * outside the new root!
1568                          */
1569                         homedir = "/";
1570                 }
1571                 /*
1572                  * Finally, do chroot()
1573                  */
1574                 if (chroot(chrootdir) < 0) {
1575                         reply(550, "Can't change root.");
1576                         goto bad;
1577                 }
1578                 __FreeBSD_libc_enter_restricted_mode();
1579         } else  /* real user w/o chroot */
1580                 homedir = pw->pw_dir;
1581         /*
1582          * Set euid *before* doing chdir() so
1583          * a) the user won't be carried to a directory that he couldn't reach
1584          *    on his own due to no permission to upper path components,
1585          * b) NFS mounted homedirs w/restrictive permissions will be accessible
1586          *    (uid 0 has no root power over NFS if not mapped explicitly.)
1587          */
1588         if (seteuid(pw->pw_uid) < 0) {
1589                 reply(550, "Can't set uid.");
1590                 goto bad;
1591         }
1592         if (chdir(homedir) < 0) {
1593                 if (guest || dochroot) {
1594                         reply(550, "Can't change to base directory.");
1595                         goto bad;
1596                 } else {
1597                         if (chdir("/") < 0) {
1598                                 reply(550, "Root is inaccessible.");
1599                                 goto bad;
1600                         }
1601                         lreply(230, "No directory! Logging in with home=/.");
1602                 }
1603         }
1604
1605         /*
1606          * Display a login message, if it exists.
1607          * N.B. reply(230,) must follow the message.
1608          */
1609 #ifdef VIRTUAL_HOSTING
1610         fd = fopen(thishost->loginmsg, "r");
1611 #else
1612         fd = fopen(_PATH_FTPLOGINMESG, "r");
1613 #endif
1614         if (fd != NULL) {
1615                 char *cp, line[LINE_MAX];
1616
1617                 while (fgets(line, sizeof(line), fd) != NULL) {
1618                         if ((cp = strchr(line, '\n')) != NULL)
1619                                 *cp = '\0';
1620                         lreply(230, "%s", line);
1621                 }
1622                 (void) fflush(stdout);
1623                 (void) fclose(fd);
1624         }
1625         if (guest) {
1626                 if (ident != NULL)
1627                         free(ident);
1628                 ident = strdup(passwd);
1629                 if (ident == NULL)
1630                         fatalerror("Ran out of memory.");
1631
1632                 reply(230, "Guest login ok, access restrictions apply.");
1633 #ifdef SETPROCTITLE
1634 #ifdef VIRTUAL_HOSTING
1635                 if (thishost != firsthost)
1636                         snprintf(proctitle, sizeof(proctitle),
1637                                  "%s: anonymous(%s)/%s", remotehost, hostname,
1638                                  passwd);
1639                 else
1640 #endif
1641                         snprintf(proctitle, sizeof(proctitle),
1642                                  "%s: anonymous/%s", remotehost, passwd);
1643                 setproctitle("%s", proctitle);
1644 #endif /* SETPROCTITLE */
1645                 if (logging)
1646                         syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s",
1647                             remotehost, passwd);
1648         } else {
1649                 if (dochroot)
1650                         reply(230, "User %s logged in, "
1651                                    "access restrictions apply.", pw->pw_name);
1652                 else
1653                         reply(230, "User %s logged in.", pw->pw_name);
1654
1655 #ifdef SETPROCTITLE
1656                 snprintf(proctitle, sizeof(proctitle),
1657                          "%s: user/%s", remotehost, pw->pw_name);
1658                 setproctitle("%s", proctitle);
1659 #endif /* SETPROCTITLE */
1660                 if (logging)
1661                         syslog(LOG_INFO, "FTP LOGIN FROM %s as %s",
1662                             remotehost, pw->pw_name);
1663         }
1664         if (logging && (guest || dochroot))
1665                 syslog(LOG_INFO, "session root changed to %s", chrootdir);
1666 #ifdef  LOGIN_CAP
1667         login_close(lc);
1668 #endif
1669         if (residue)
1670                 free(residue);
1671         return;
1672 bad:
1673         /* Forget all about it... */
1674 #ifdef  LOGIN_CAP
1675         login_close(lc);
1676 #endif
1677         if (residue)
1678                 free(residue);
1679         end_login();
1680 }
1681
1682 void
1683 retrieve(char *cmd, char *name)
1684 {
1685         FILE *fin, *dout;
1686         struct stat st;
1687         int (*closefunc)(FILE *);
1688         time_t start;
1689         char line[BUFSIZ];
1690
1691         if (cmd == 0) {
1692                 fin = fopen(name, "r"), closefunc = fclose;
1693                 st.st_size = 0;
1694         } else {
1695                 (void) snprintf(line, sizeof(line), cmd, name);
1696                 name = line;
1697                 fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose;
1698                 st.st_size = -1;
1699                 st.st_blksize = BUFSIZ;
1700         }
1701         if (fin == NULL) {
1702                 if (errno != 0) {
1703                         perror_reply(550, name);
1704                         if (cmd == 0) {
1705                                 LOGCMD("get", name);
1706                         }
1707                 }
1708                 return;
1709         }
1710         byte_count = -1;
1711         if (cmd == 0) {
1712                 if (fstat(fileno(fin), &st) < 0) {
1713                         perror_reply(550, name);
1714                         goto done;
1715                 }
1716                 if (!S_ISREG(st.st_mode)) {
1717                         /*
1718                          * Never sending a raw directory is a workaround
1719                          * for buggy clients that will attempt to RETR
1720                          * a directory before listing it, e.g., Mozilla.
1721                          * Preventing a guest from getting irregular files
1722                          * is a simple security measure.
1723                          */
1724                         if (S_ISDIR(st.st_mode) || guest) {
1725                                 reply(550, "%s: not a plain file.", name);
1726                                 goto done;
1727                         }
1728                         st.st_size = -1;
1729                         /* st.st_blksize is set for all descriptor types */
1730                 }
1731         }
1732         if (restart_point) {
1733                 if (type == TYPE_A) {
1734                         off_t i, n;
1735                         int c;
1736
1737                         n = restart_point;
1738                         i = 0;
1739                         while (i++ < n) {
1740                                 if ((c=getc(fin)) == EOF) {
1741                                         perror_reply(550, name);
1742                                         goto done;
1743                                 }
1744                                 if (c == '\n')
1745                                         i++;
1746                         }
1747                 } else if (lseek(fileno(fin), restart_point, L_SET) < 0) {
1748                         perror_reply(550, name);
1749                         goto done;
1750                 }
1751         }
1752         dout = dataconn(name, st.st_size, "w");
1753         if (dout == NULL)
1754                 goto done;
1755         time(&start);
1756         send_data(fin, dout, st.st_blksize, st.st_size,
1757                   restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode));
1758         if (cmd == 0 && guest && stats && byte_count > 0)
1759                 logxfer(name, byte_count, start);
1760         (void) fclose(dout);
1761         data = -1;
1762         pdata = -1;
1763 done:
1764         if (cmd == 0)
1765                 LOGBYTES("get", name, byte_count);
1766         (*closefunc)(fin);
1767 }
1768
1769 void
1770 store(char *name, char *mode, int unique)
1771 {
1772         int fd;
1773         FILE *fout, *din;
1774         int (*closefunc)(FILE *);
1775
1776         if (*mode == 'a') {             /* APPE */
1777                 if (unique) {
1778                         /* Programming error */
1779                         syslog(LOG_ERR, "Internal: unique flag to APPE");
1780                         unique = 0;
1781                 }
1782                 if (guest && noguestmod) {
1783                         reply(550, "Appending to existing file denied.");
1784                         goto err;
1785                 }
1786                 restart_point = 0;      /* not affected by preceding REST */
1787         }
1788         if (unique)                     /* STOU overrides REST */
1789                 restart_point = 0;
1790         if (guest && noguestmod) {
1791                 if (restart_point) {    /* guest STOR w/REST */
1792                         reply(550, "Modifying existing file denied.");
1793                         goto err;
1794                 } else                  /* treat guest STOR as STOU */
1795                         unique = 1;
1796         }
1797
1798         if (restart_point)
1799                 mode = "r+";    /* so ASCII manual seek can work */
1800         if (unique) {
1801                 if ((fd = guniquefd(name, &name)) < 0)
1802                         goto err;
1803                 fout = fdopen(fd, mode);
1804         } else
1805                 fout = fopen(name, mode);
1806         closefunc = fclose;
1807         if (fout == NULL) {
1808                 perror_reply(553, name);
1809                 goto err;
1810         }
1811         byte_count = -1;
1812         if (restart_point) {
1813                 if (type == TYPE_A) {
1814                         off_t i, n;
1815                         int c;
1816
1817                         n = restart_point;
1818                         i = 0;
1819                         while (i++ < n) {
1820                                 if ((c=getc(fout)) == EOF) {
1821                                         perror_reply(550, name);
1822                                         goto done;
1823                                 }
1824                                 if (c == '\n')
1825                                         i++;
1826                         }
1827                         /*
1828                          * We must do this seek to "current" position
1829                          * because we are changing from reading to
1830                          * writing.
1831                          */
1832                         if (fseeko(fout, 0, SEEK_CUR) < 0) {
1833                                 perror_reply(550, name);
1834                                 goto done;
1835                         }
1836                 } else if (lseek(fileno(fout), restart_point, L_SET) < 0) {
1837                         perror_reply(550, name);
1838                         goto done;
1839                 }
1840         }
1841         din = dataconn(name, -1, "r");
1842         if (din == NULL)
1843                 goto done;
1844         if (receive_data(din, fout) == 0) {
1845                 if (unique)
1846                         reply(226, "Transfer complete (unique file name:%s).",
1847                             name);
1848                 else
1849                         reply(226, "Transfer complete.");
1850         }
1851         (void) fclose(din);
1852         data = -1;
1853         pdata = -1;
1854 done:
1855         LOGBYTES(*mode == 'a' ? "append" : "put", name, byte_count);
1856         (*closefunc)(fout);
1857         return;
1858 err:
1859         LOGCMD(*mode == 'a' ? "append" : "put" , name);
1860         return;
1861 }
1862
1863 static FILE *
1864 getdatasock(char *mode)
1865 {
1866         int on = 1, s, t, tries;
1867
1868         if (data >= 0)
1869                 return (fdopen(data, mode));
1870
1871         s = socket(data_dest.su_family, SOCK_STREAM, 0);
1872         if (s < 0)
1873                 goto bad;
1874         if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
1875                 syslog(LOG_WARNING, "data setsockopt (SO_REUSEADDR): %m");
1876         /* anchor socket to avoid multi-homing problems */
1877         data_source = ctrl_addr;
1878         data_source.su_port = htons(dataport);
1879         (void) seteuid(0);
1880         for (tries = 1; ; tries++) {
1881                 /*
1882                  * We should loop here since it's possible that
1883                  * another ftpd instance has passed this point and is
1884                  * trying to open a data connection in active mode now.
1885                  * Until the other connection is opened, we'll be getting
1886                  * EADDRINUSE because no SOCK_STREAM sockets in the system
1887                  * can share both local and remote addresses, localIP:20
1888                  * and *:* in this case.
1889                  */
1890                 if (bind(s, (struct sockaddr *)&data_source,
1891                     data_source.su_len) >= 0)
1892                         break;
1893                 if (errno != EADDRINUSE || tries > 10)
1894                         goto bad;
1895                 sleep(tries);
1896         }
1897         (void) seteuid(pw->pw_uid);
1898 #ifdef IP_TOS
1899         if (data_source.su_family == AF_INET)
1900       {
1901         on = IPTOS_THROUGHPUT;
1902         if (setsockopt(s, IPPROTO_IP, IP_TOS, &on, sizeof(int)) < 0)
1903                 syslog(LOG_WARNING, "data setsockopt (IP_TOS): %m");
1904       }
1905 #endif
1906 #ifdef TCP_NOPUSH
1907         /*
1908          * Turn off push flag to keep sender TCP from sending short packets
1909          * at the boundaries of each write().
1910          */
1911         on = 1;
1912         if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, &on, sizeof on) < 0)
1913                 syslog(LOG_WARNING, "data setsockopt (TCP_NOPUSH): %m");
1914 #endif
1915         return (fdopen(s, mode));
1916 bad:
1917         /* Return the real value of errno (close may change it) */
1918         t = errno;
1919         (void) seteuid(pw->pw_uid);
1920         (void) close(s);
1921         errno = t;
1922         return (NULL);
1923 }
1924
1925 static FILE *
1926 dataconn(char *name, off_t size, char *mode)
1927 {
1928         char sizebuf[32];
1929         FILE *file;
1930         int retry = 0, tos, conerrno;
1931
1932         file_size = size;
1933         byte_count = 0;
1934         if (size != -1)
1935                 (void) snprintf(sizebuf, sizeof(sizebuf),
1936                                 " (%jd bytes)", (intmax_t)size);
1937         else
1938                 *sizebuf = '\0';
1939         if (pdata >= 0) {
1940                 union sockunion from;
1941                 socklen_t fromlen = ctrl_addr.su_len;
1942                 int flags, s;
1943                 struct timeval timeout;
1944                 fd_set set;
1945
1946                 FD_ZERO(&set);
1947                 FD_SET(pdata, &set);
1948
1949                 timeout.tv_usec = 0;
1950                 timeout.tv_sec = 120;
1951
1952                 /*
1953                  * Granted a socket is in the blocking I/O mode,
1954                  * accept() will block after a successful select()
1955                  * if the selected connection dies in between.
1956                  * Therefore set the non-blocking I/O flag here.
1957                  */
1958                 if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1959                     fcntl(pdata, F_SETFL, flags | O_NONBLOCK) == -1)
1960                         goto pdata_err;
1961                 if (select(pdata+1, &set, NULL, NULL, &timeout) <= 0 ||
1962                     (s = accept(pdata, (struct sockaddr *) &from, &fromlen)) < 0)
1963                         goto pdata_err;
1964                 (void) close(pdata);
1965                 pdata = s;
1966                 /*
1967                  * Unset the inherited non-blocking I/O flag
1968                  * on the child socket so stdio can work on it.
1969                  */
1970                 if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1971                     fcntl(pdata, F_SETFL, flags & ~O_NONBLOCK) == -1)
1972                         goto pdata_err;
1973 #ifdef IP_TOS
1974                 if (from.su_family == AF_INET)
1975               {
1976                 tos = IPTOS_THROUGHPUT;
1977                 if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
1978                         syslog(LOG_WARNING, "pdata setsockopt (IP_TOS): %m");
1979               }
1980 #endif
1981                 reply(150, "Opening %s mode data connection for '%s'%s.",
1982                      type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
1983                 return (fdopen(pdata, mode));
1984 pdata_err:
1985                 reply(425, "Can't open data connection.");
1986                 (void) close(pdata);
1987                 pdata = -1;
1988                 return (NULL);
1989         }
1990         if (data >= 0) {
1991                 reply(125, "Using existing data connection for '%s'%s.",
1992                     name, sizebuf);
1993                 usedefault = 1;
1994                 return (fdopen(data, mode));
1995         }
1996         if (usedefault)
1997                 data_dest = his_addr;
1998         usedefault = 1;
1999         do {
2000                 file = getdatasock(mode);
2001                 if (file == NULL) {
2002                         char hostbuf[NI_MAXHOST], portbuf[NI_MAXSERV];
2003
2004                         if (getnameinfo((struct sockaddr *)&data_source,
2005                                 data_source.su_len,
2006                                 hostbuf, sizeof(hostbuf) - 1,
2007                                 portbuf, sizeof(portbuf) - 1,
2008                                 NI_NUMERICHOST|NI_NUMERICSERV))
2009                                         *hostbuf = *portbuf = 0;
2010                         hostbuf[sizeof(hostbuf) - 1] = 0;
2011                         portbuf[sizeof(portbuf) - 1] = 0;
2012                         reply(425, "Can't create data socket (%s,%s): %s.",
2013                                 hostbuf, portbuf, strerror(errno));
2014                         return (NULL);
2015                 }
2016                 data = fileno(file);
2017                 conerrno = 0;
2018                 if (connect(data, (struct sockaddr *)&data_dest,
2019                     data_dest.su_len) == 0)
2020                         break;
2021                 conerrno = errno;
2022                 (void) fclose(file);
2023                 data = -1;
2024                 if (conerrno == EADDRINUSE) {
2025                         sleep(swaitint);
2026                         retry += swaitint;
2027                 } else {
2028                         break;
2029                 }
2030         } while (retry <= swaitmax);
2031         if (conerrno != 0) {
2032                 reply(425, "Can't build data connection: %s.",
2033                            strerror(conerrno));
2034                 return (NULL);
2035         }
2036         reply(150, "Opening %s mode data connection for '%s'%s.",
2037              type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
2038         return (file);
2039 }
2040
2041 /*
2042  * A helper macro to avoid code duplication
2043  * in send_data() and receive_data().
2044  *
2045  * XXX We have to block SIGURG during putc() because BSD stdio
2046  * is unable to restart interrupted write operations and hence
2047  * the entire buffer contents will be lost as soon as a write()
2048  * call indicates EINTR to stdio.
2049  */
2050 #define FTPD_PUTC(ch, file, label)                                      \
2051         do {                                                            \
2052                 int ret;                                                \
2053                                                                         \
2054                 do {                                                    \
2055                         START_UNSAFE;                                   \
2056                         ret = putc((ch), (file));                       \
2057                         END_UNSAFE;                                     \
2058                         CHECKOOB(return (-1))                           \
2059                         else if (ferror(file))                          \
2060                                 goto label;                             \
2061                         clearerr(file);                                 \
2062                 } while (ret == EOF);                                   \
2063         } while (0)
2064
2065 /*
2066  * Transfer the contents of "instr" to "outstr" peer using the appropriate
2067  * encapsulation of the data subject to Mode, Structure, and Type.
2068  *
2069  * NB: Form isn't handled.
2070  */
2071 static int
2072 send_data(FILE *instr, FILE *outstr, size_t blksize, off_t filesize, int isreg)
2073 {
2074         int c, cp, filefd, netfd;
2075         char *buf;
2076
2077         STARTXFER;
2078
2079         switch (type) {
2080
2081         case TYPE_A:
2082                 cp = EOF;
2083                 for (;;) {
2084                         c = getc(instr);
2085                         CHECKOOB(return (-1))
2086                         else if (c == EOF && ferror(instr))
2087                                 goto file_err;
2088                         if (c == EOF) {
2089                                 if (ferror(instr)) {    /* resume after OOB */
2090                                         clearerr(instr);
2091                                         continue;
2092                                 }
2093                                 if (feof(instr))        /* EOF */
2094                                         break;
2095                                 syslog(LOG_ERR, "Internal: impossible condition"
2096                                                 " on file after getc()");
2097                                 goto file_err;
2098                         }
2099                         if (c == '\n' && cp != '\r') {
2100                                 FTPD_PUTC('\r', outstr, data_err);
2101                                 byte_count++;
2102                         }
2103                         FTPD_PUTC(c, outstr, data_err);
2104                         byte_count++;
2105                         cp = c;
2106                 }
2107 #ifdef notyet   /* BSD stdio isn't ready for that */
2108                 while (fflush(outstr) == EOF) {
2109                         CHECKOOB(return (-1))
2110                         else
2111                                 goto data_err;
2112                         clearerr(outstr);
2113                 }
2114                 ENDXFER;
2115 #else
2116                 ENDXFER;
2117                 if (fflush(outstr) == EOF)
2118                         goto data_err;
2119 #endif
2120                 reply(226, "Transfer complete.");
2121                 return (0);
2122
2123         case TYPE_I:
2124         case TYPE_L:
2125                 /*
2126                  * isreg is only set if we are not doing restart and we
2127                  * are sending a regular file
2128                  */
2129                 netfd = fileno(outstr);
2130                 filefd = fileno(instr);
2131
2132                 if (isreg) {
2133                         char *msg = "Transfer complete.";
2134                         off_t cnt, offset;
2135                         int err;
2136
2137                         cnt = offset = 0;
2138
2139                         while (filesize > 0) {
2140                                 err = sendfile(filefd, netfd, offset, 0,
2141                                                NULL, &cnt, 0);
2142                                 /*
2143                                  * Calculate byte_count before OOB processing.
2144                                  * It can be used in myoob() later.
2145                                  */
2146                                 byte_count += cnt;
2147                                 offset += cnt;
2148                                 filesize -= cnt;
2149                                 CHECKOOB(return (-1))
2150                                 else if (err == -1) {
2151                                         if (errno != EINTR &&
2152                                             cnt == 0 && offset == 0)
2153                                                 goto oldway;
2154                                         goto data_err;
2155                                 }
2156                                 if (err == -1)  /* resume after OOB */
2157                                         continue;
2158                                 /*
2159                                  * We hit the EOF prematurely.
2160                                  * Perhaps the file was externally truncated.
2161                                  */
2162                                 if (cnt == 0) {
2163                                         msg = "Transfer finished due to "
2164                                               "premature end of file.";
2165                                         break;
2166                                 }
2167                         }
2168                         ENDXFER;
2169                         reply(226, "%s", msg);
2170                         return (0);
2171                 }
2172
2173 oldway:
2174                 if ((buf = malloc(blksize)) == NULL) {
2175                         ENDXFER;
2176                         reply(451, "Ran out of memory.");
2177                         return (-1);
2178                 }
2179
2180                 for (;;) {
2181                         int cnt, len;
2182                         char *bp;
2183
2184                         cnt = read(filefd, buf, blksize);
2185                         CHECKOOB(free(buf); return (-1))
2186                         else if (cnt < 0) {
2187                                 free(buf);
2188                                 goto file_err;
2189                         }
2190                         if (cnt < 0)    /* resume after OOB */
2191                                 continue;
2192                         if (cnt == 0)   /* EOF */
2193                                 break;
2194                         for (len = cnt, bp = buf; len > 0;) {
2195                                 cnt = write(netfd, bp, len);
2196                                 CHECKOOB(free(buf); return (-1))
2197                                 else if (cnt < 0) {
2198                                         free(buf);
2199                                         goto data_err;
2200                                 }
2201                                 if (cnt <= 0)
2202                                         continue;
2203                                 len -= cnt;
2204                                 bp += cnt;
2205                                 byte_count += cnt;
2206                         }
2207                 }
2208                 ENDXFER;
2209                 free(buf);
2210                 reply(226, "Transfer complete.");
2211                 return (0);
2212         default:
2213                 ENDXFER;
2214                 reply(550, "Unimplemented TYPE %d in send_data.", type);
2215                 return (-1);
2216         }
2217
2218 data_err:
2219         ENDXFER;
2220         perror_reply(426, "Data connection");
2221         return (-1);
2222
2223 file_err:
2224         ENDXFER;
2225         perror_reply(551, "Error on input file");
2226         return (-1);
2227 }
2228
2229 /*
2230  * Transfer data from peer to "outstr" using the appropriate encapulation of
2231  * the data subject to Mode, Structure, and Type.
2232  *
2233  * N.B.: Form isn't handled.
2234  */
2235 static int
2236 receive_data(FILE *instr, FILE *outstr)
2237 {
2238         int c, cp;
2239         int bare_lfs = 0;
2240
2241         STARTXFER;
2242
2243         switch (type) {
2244
2245         case TYPE_I:
2246         case TYPE_L:
2247                 for (;;) {
2248                         int cnt, len;
2249                         char *bp;
2250                         char buf[BUFSIZ];
2251
2252                         cnt = read(fileno(instr), buf, sizeof(buf));
2253                         CHECKOOB(return (-1))
2254                         else if (cnt < 0)
2255                                 goto data_err;
2256                         if (cnt < 0)    /* resume after OOB */
2257                                 continue;
2258                         if (cnt == 0)   /* EOF */
2259                                 break;
2260                         for (len = cnt, bp = buf; len > 0;) {
2261                                 cnt = write(fileno(outstr), bp, len);
2262                                 CHECKOOB(return (-1))
2263                                 else if (cnt < 0)
2264                                         goto file_err;
2265                                 if (cnt <= 0)
2266                                         continue;
2267                                 len -= cnt;
2268                                 bp += cnt;
2269                                 byte_count += cnt;
2270                         }
2271                 }
2272                 ENDXFER;
2273                 return (0);
2274
2275         case TYPE_E:
2276                 ENDXFER;
2277                 reply(553, "TYPE E not implemented.");
2278                 return (-1);
2279
2280         case TYPE_A:
2281                 cp = EOF;
2282                 for (;;) {
2283                         c = getc(instr);
2284                         CHECKOOB(return (-1))
2285                         else if (c == EOF && ferror(instr))
2286                                 goto data_err;
2287                         if (c == EOF && ferror(instr)) { /* resume after OOB */
2288                                 clearerr(instr);
2289                                 continue;
2290                         }
2291
2292                         if (cp == '\r') {
2293                                 if (c != '\n')
2294                                         FTPD_PUTC('\r', outstr, file_err);
2295                         } else
2296                                 if (c == '\n')
2297                                         bare_lfs++;
2298                         if (c == '\r') {
2299                                 byte_count++;
2300                                 cp = c;
2301                                 continue;
2302                         }
2303
2304                         /* Check for EOF here in order not to lose last \r. */
2305                         if (c == EOF) {
2306                                 if (feof(instr))        /* EOF */
2307                                         break;
2308                                 syslog(LOG_ERR, "Internal: impossible condition"
2309                                                 " on data stream after getc()");
2310                                 goto data_err;
2311                         }
2312
2313                         byte_count++;
2314                         FTPD_PUTC(c, outstr, file_err);
2315                         cp = c;
2316                 }
2317 #ifdef notyet   /* BSD stdio isn't ready for that */
2318                 while (fflush(outstr) == EOF) {
2319                         CHECKOOB(return (-1))
2320                         else
2321                                 goto file_err;
2322                         clearerr(outstr);
2323                 }
2324                 ENDXFER;
2325 #else
2326                 ENDXFER;
2327                 if (fflush(outstr) == EOF)
2328                         goto file_err;
2329 #endif
2330                 if (bare_lfs) {
2331                         lreply(226,
2332                 "WARNING! %d bare linefeeds received in ASCII mode.",
2333                             bare_lfs);
2334                 (void)printf("   File may not have transferred correctly.\r\n");
2335                 }
2336                 return (0);
2337         default:
2338                 ENDXFER;
2339                 reply(550, "Unimplemented TYPE %d in receive_data.", type);
2340                 return (-1);
2341         }
2342
2343 data_err:
2344         ENDXFER;
2345         perror_reply(426, "Data connection");
2346         return (-1);
2347
2348 file_err:
2349         ENDXFER;
2350         perror_reply(452, "Error writing to file");
2351         return (-1);
2352 }
2353
2354 void
2355 statfilecmd(char *filename)
2356 {
2357         FILE *fin;
2358         int atstart;
2359         int c, code;
2360         char line[LINE_MAX];
2361         struct stat st;
2362
2363         code = lstat(filename, &st) == 0 && S_ISDIR(st.st_mode) ? 212 : 213;
2364         (void)snprintf(line, sizeof(line), _PATH_LS " -lgA %s", filename);
2365         fin = ftpd_popen(line, "r");
2366         if (fin == NULL) {
2367                 perror_reply(551, filename);
2368                 return;
2369         }
2370         lreply(code, "Status of %s:", filename);
2371         atstart = 1;
2372         while ((c = getc(fin)) != EOF) {
2373                 if (c == '\n') {
2374                         if (ferror(stdout)){
2375                                 perror_reply(421, "Control connection");
2376                                 (void) ftpd_pclose(fin);
2377                                 dologout(1);
2378                                 /* NOTREACHED */
2379                         }
2380                         if (ferror(fin)) {
2381                                 perror_reply(551, filename);
2382                                 (void) ftpd_pclose(fin);
2383                                 return;
2384                         }
2385                         (void) putc('\r', stdout);
2386                 }
2387                 /*
2388                  * RFC 959 says neutral text should be prepended before
2389                  * a leading 3-digit number followed by whitespace, but
2390                  * many ftp clients can be confused by any leading digits,
2391                  * as a matter of fact.
2392                  */
2393                 if (atstart && isdigit(c))
2394                         (void) putc(' ', stdout);
2395                 (void) putc(c, stdout);
2396                 atstart = (c == '\n');
2397         }
2398         (void) ftpd_pclose(fin);
2399         reply(code, "End of status.");
2400 }
2401
2402 void
2403 statcmd(void)
2404 {
2405         union sockunion *su;
2406         u_char *a, *p;
2407         char hname[NI_MAXHOST];
2408         int ispassive;
2409
2410         if (hostinfo) {
2411                 lreply(211, "%s FTP server status:", hostname);
2412                 printf("     %s\r\n", version);
2413         } else
2414                 lreply(211, "FTP server status:");
2415         printf("     Connected to %s", remotehost);
2416         if (!getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
2417                          hname, sizeof(hname) - 1, NULL, 0, NI_NUMERICHOST)) {
2418                 hname[sizeof(hname) - 1] = 0;
2419                 if (strcmp(hname, remotehost) != 0)
2420                         printf(" (%s)", hname);
2421         }
2422         printf("\r\n");
2423         if (logged_in) {
2424                 if (guest)
2425                         printf("     Logged in anonymously\r\n");
2426                 else
2427                         printf("     Logged in as %s\r\n", pw->pw_name);
2428         } else if (askpasswd)
2429                 printf("     Waiting for password\r\n");
2430         else
2431                 printf("     Waiting for user name\r\n");
2432         printf("     TYPE: %s", typenames[type]);
2433         if (type == TYPE_A || type == TYPE_E)
2434                 printf(", FORM: %s", formnames[form]);
2435         if (type == TYPE_L)
2436 #if CHAR_BIT == 8
2437                 printf(" %d", CHAR_BIT);
2438 #else
2439                 printf(" %d", bytesize);        /* need definition! */
2440 #endif
2441         printf("; STRUcture: %s; transfer MODE: %s\r\n",
2442             strunames[stru], modenames[mode]);
2443         if (data != -1)
2444                 printf("     Data connection open\r\n");
2445         else if (pdata != -1) {
2446                 ispassive = 1;
2447                 su = &pasv_addr;
2448                 goto printaddr;
2449         } else if (usedefault == 0) {
2450                 ispassive = 0;
2451                 su = &data_dest;
2452 printaddr:
2453 #define UC(b) (((int) b) & 0xff)
2454                 if (epsvall) {
2455                         printf("     EPSV only mode (EPSV ALL)\r\n");
2456                         goto epsvonly;
2457                 }
2458
2459                 /* PORT/PASV */
2460                 if (su->su_family == AF_INET) {
2461                         a = (u_char *) &su->su_sin.sin_addr;
2462                         p = (u_char *) &su->su_sin.sin_port;
2463                         printf("     %s (%d,%d,%d,%d,%d,%d)\r\n",
2464                                 ispassive ? "PASV" : "PORT",
2465                                 UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2466                                 UC(p[0]), UC(p[1]));
2467                 }
2468
2469                 /* LPRT/LPSV */
2470             {
2471                 int alen, af, i;
2472
2473                 switch (su->su_family) {
2474                 case AF_INET:
2475                         a = (u_char *) &su->su_sin.sin_addr;
2476                         p = (u_char *) &su->su_sin.sin_port;
2477                         alen = sizeof(su->su_sin.sin_addr);
2478                         af = 4;
2479                         break;
2480                 case AF_INET6:
2481                         a = (u_char *) &su->su_sin6.sin6_addr;
2482                         p = (u_char *) &su->su_sin6.sin6_port;
2483                         alen = sizeof(su->su_sin6.sin6_addr);
2484                         af = 6;
2485                         break;
2486                 default:
2487                         af = 0;
2488                         break;
2489                 }
2490                 if (af) {
2491                         printf("     %s (%d,%d,", ispassive ? "LPSV" : "LPRT",
2492                                 af, alen);
2493                         for (i = 0; i < alen; i++)
2494                                 printf("%d,", UC(a[i]));
2495                         printf("%d,%d,%d)\r\n", 2, UC(p[0]), UC(p[1]));
2496                 }
2497             }
2498
2499 epsvonly:;
2500                 /* EPRT/EPSV */
2501             {
2502                 int af;
2503
2504                 switch (su->su_family) {
2505                 case AF_INET:
2506                         af = 1;
2507                         break;
2508                 case AF_INET6:
2509                         af = 2;
2510                         break;
2511                 default:
2512                         af = 0;
2513                         break;
2514                 }
2515                 if (af) {
2516                         union sockunion tmp;
2517
2518                         tmp = *su;
2519                         if (tmp.su_family == AF_INET6)
2520                                 tmp.su_sin6.sin6_scope_id = 0;
2521                         if (!getnameinfo((struct sockaddr *)&tmp, tmp.su_len,
2522                                         hname, sizeof(hname) - 1, NULL, 0,
2523                                         NI_NUMERICHOST)) {
2524                                 hname[sizeof(hname) - 1] = 0;
2525                                 printf("     %s |%d|%s|%d|\r\n",
2526                                         ispassive ? "EPSV" : "EPRT",
2527                                         af, hname, htons(tmp.su_port));
2528                         }
2529                 }
2530             }
2531 #undef UC
2532         } else
2533                 printf("     No data connection\r\n");
2534         reply(211, "End of status.");
2535 }
2536
2537 void
2538 fatalerror(char *s)
2539 {
2540
2541         reply(451, "Error in server: %s", s);
2542         reply(221, "Closing connection due to server error.");
2543         dologout(0);
2544         /* NOTREACHED */
2545 }
2546
2547 void
2548 reply(int n, const char *fmt, ...)
2549 {
2550         va_list ap;
2551
2552         (void)printf("%d ", n);
2553         va_start(ap, fmt);
2554         (void)vprintf(fmt, ap);
2555         va_end(ap);
2556         (void)printf("\r\n");
2557         (void)fflush(stdout);
2558         if (ftpdebug) {
2559                 syslog(LOG_DEBUG, "<--- %d ", n);
2560                 va_start(ap, fmt);
2561                 vsyslog(LOG_DEBUG, fmt, ap);
2562                 va_end(ap);
2563         }
2564 }
2565
2566 void
2567 lreply(int n, const char *fmt, ...)
2568 {
2569         va_list ap;
2570
2571         (void)printf("%d- ", n);
2572         va_start(ap, fmt);
2573         (void)vprintf(fmt, ap);
2574         va_end(ap);
2575         (void)printf("\r\n");
2576         (void)fflush(stdout);
2577         if (ftpdebug) {
2578                 syslog(LOG_DEBUG, "<--- %d- ", n);
2579                 va_start(ap, fmt);
2580                 vsyslog(LOG_DEBUG, fmt, ap);
2581                 va_end(ap);
2582         }
2583 }
2584
2585 static void
2586 ack(char *s)
2587 {
2588
2589         reply(250, "%s command successful.", s);
2590 }
2591
2592 void
2593 nack(char *s)
2594 {
2595
2596         reply(502, "%s command not implemented.", s);
2597 }
2598
2599 /* ARGSUSED */
2600 void
2601 yyerror(char *s)
2602 {
2603         char *cp;
2604
2605         if ((cp = strchr(cbuf,'\n')))
2606                 *cp = '\0';
2607         reply(500, "%s: command not understood.", cbuf);
2608 }
2609
2610 void
2611 delete(char *name)
2612 {
2613         struct stat st;
2614
2615         LOGCMD("delete", name);
2616         if (lstat(name, &st) < 0) {
2617                 perror_reply(550, name);
2618                 return;
2619         }
2620         if (S_ISDIR(st.st_mode)) {
2621                 if (rmdir(name) < 0) {
2622                         perror_reply(550, name);
2623                         return;
2624                 }
2625                 goto done;
2626         }
2627         if (guest && noguestmod) {
2628                 reply(550, "Operation not permitted.");
2629                 return;
2630         }
2631         if (unlink(name) < 0) {
2632                 perror_reply(550, name);
2633                 return;
2634         }
2635 done:
2636         ack("DELE");
2637 }
2638
2639 void
2640 cwd(char *path)
2641 {
2642
2643         if (chdir(path) < 0)
2644                 perror_reply(550, path);
2645         else
2646                 ack("CWD");
2647 }
2648
2649 void
2650 makedir(char *name)
2651 {
2652         char *s;
2653
2654         LOGCMD("mkdir", name);
2655         if (guest && noguestmkd)
2656                 reply(550, "Operation not permitted.");
2657         else if (mkdir(name, 0777) < 0)
2658                 perror_reply(550, name);
2659         else {
2660                 if ((s = doublequote(name)) == NULL)
2661                         fatalerror("Ran out of memory.");
2662                 reply(257, "\"%s\" directory created.", s);
2663                 free(s);
2664         }
2665 }
2666
2667 void
2668 removedir(char *name)
2669 {
2670
2671         LOGCMD("rmdir", name);
2672         if (rmdir(name) < 0)
2673                 perror_reply(550, name);
2674         else
2675                 ack("RMD");
2676 }
2677
2678 void
2679 pwd(void)
2680 {
2681         char *s, path[MAXPATHLEN + 1];
2682
2683         if (getcwd(path, sizeof(path)) == NULL)
2684                 perror_reply(550, "Get current directory");
2685         else {
2686                 if ((s = doublequote(path)) == NULL)
2687                         fatalerror("Ran out of memory.");
2688                 reply(257, "\"%s\" is current directory.", s);
2689                 free(s);
2690         }
2691 }
2692
2693 char *
2694 renamefrom(char *name)
2695 {
2696         struct stat st;
2697
2698         if (guest && noguestmod) {
2699                 reply(550, "Operation not permitted.");
2700                 return (NULL);
2701         }
2702         if (lstat(name, &st) < 0) {
2703                 perror_reply(550, name);
2704                 return (NULL);
2705         }
2706         reply(350, "File exists, ready for destination name.");
2707         return (name);
2708 }
2709
2710 void
2711 renamecmd(char *from, char *to)
2712 {
2713         struct stat st;
2714
2715         LOGCMD2("rename", from, to);
2716
2717         if (guest && (stat(to, &st) == 0)) {
2718                 reply(550, "%s: permission denied.", to);
2719                 return;
2720         }
2721
2722         if (rename(from, to) < 0)
2723                 perror_reply(550, "rename");
2724         else
2725                 ack("RNTO");
2726 }
2727
2728 static void
2729 dolog(struct sockaddr *who)
2730 {
2731         char who_name[NI_MAXHOST];
2732
2733         realhostname_sa(remotehost, sizeof(remotehost) - 1, who, who->sa_len);
2734         remotehost[sizeof(remotehost) - 1] = 0;
2735         if (getnameinfo(who, who->sa_len,
2736                 who_name, sizeof(who_name) - 1, NULL, 0, NI_NUMERICHOST))
2737                         *who_name = 0;
2738         who_name[sizeof(who_name) - 1] = 0;
2739
2740 #ifdef SETPROCTITLE
2741 #ifdef VIRTUAL_HOSTING
2742         if (thishost != firsthost)
2743                 snprintf(proctitle, sizeof(proctitle), "%s: connected (to %s)",
2744                          remotehost, hostname);
2745         else
2746 #endif
2747                 snprintf(proctitle, sizeof(proctitle), "%s: connected",
2748                          remotehost);
2749         setproctitle("%s", proctitle);
2750 #endif /* SETPROCTITLE */
2751
2752         if (logging) {
2753 #ifdef VIRTUAL_HOSTING
2754                 if (thishost != firsthost)
2755                         syslog(LOG_INFO, "connection from %s (%s) to %s",
2756                                remotehost, who_name, hostname);
2757                 else
2758 #endif
2759                         syslog(LOG_INFO, "connection from %s (%s)",
2760                                remotehost, who_name);
2761         }
2762 }
2763
2764 /*
2765  * Record logout in wtmp file
2766  * and exit with supplied status.
2767  */
2768 void
2769 dologout(int status)
2770 {
2771
2772         if (logged_in && dowtmp) {
2773                 (void) seteuid(0);
2774                 ftpd_logwtmp(wtmpid, NULL, NULL);
2775         }
2776         /* beware of flushing buffers after a SIGPIPE */
2777         _exit(status);
2778 }
2779
2780 static void
2781 sigurg(int signo)
2782 {
2783
2784         recvurg = 1;
2785 }
2786
2787 static void
2788 maskurg(int flag)
2789 {
2790         int oerrno;
2791         sigset_t sset;
2792
2793         if (!transflag) {
2794                 syslog(LOG_ERR, "Internal: maskurg() while no transfer");
2795                 return;
2796         }
2797         oerrno = errno;
2798         sigemptyset(&sset);
2799         sigaddset(&sset, SIGURG);
2800         sigprocmask(flag ? SIG_BLOCK : SIG_UNBLOCK, &sset, NULL);
2801         errno = oerrno;
2802 }
2803
2804 static void
2805 flagxfer(int flag)
2806 {
2807
2808         if (flag) {
2809                 if (transflag)
2810                         syslog(LOG_ERR, "Internal: flagxfer(1): "
2811                                         "transfer already under way");
2812                 transflag = 1;
2813                 maskurg(0);
2814                 recvurg = 0;
2815         } else {
2816                 if (!transflag)
2817                         syslog(LOG_ERR, "Internal: flagxfer(0): "
2818                                         "no active transfer");
2819                 maskurg(1);
2820                 transflag = 0;
2821         }
2822 }
2823
2824 /*
2825  * Returns 0 if OK to resume or -1 if abort requested.
2826  */
2827 static int
2828 myoob(void)
2829 {
2830         char *cp;
2831         int ret;
2832
2833         if (!transflag) {
2834                 syslog(LOG_ERR, "Internal: myoob() while no transfer");
2835                 return (0);
2836         }
2837         cp = tmpline;
2838         ret = get_line(cp, 7, stdin);
2839         if (ret == -1) {
2840                 reply(221, "You could at least say goodbye.");
2841                 dologout(0);
2842         } else if (ret == -2) {
2843                 /* Ignore truncated command. */
2844                 return (0);
2845         }
2846         upper(cp);
2847         if (strcmp(cp, "ABOR\r\n") == 0) {
2848                 tmpline[0] = '\0';
2849                 reply(426, "Transfer aborted. Data connection closed.");
2850                 reply(226, "Abort successful.");
2851                 return (-1);
2852         }
2853         if (strcmp(cp, "STAT\r\n") == 0) {
2854                 tmpline[0] = '\0';
2855                 if (file_size != -1)
2856                         reply(213, "Status: %jd of %jd bytes transferred.",
2857                                    (intmax_t)byte_count, (intmax_t)file_size);
2858                 else
2859                         reply(213, "Status: %jd bytes transferred.",
2860                                    (intmax_t)byte_count);
2861         }
2862         return (0);
2863 }
2864
2865 /*
2866  * Note: a response of 425 is not mentioned as a possible response to
2867  *      the PASV command in RFC959. However, it has been blessed as
2868  *      a legitimate response by Jon Postel in a telephone conversation
2869  *      with Rick Adams on 25 Jan 89.
2870  */
2871 void
2872 passive(void)
2873 {
2874         socklen_t len;
2875         int on;
2876         char *p, *a;
2877
2878         if (pdata >= 0)         /* close old port if one set */
2879                 close(pdata);
2880
2881         pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2882         if (pdata < 0) {
2883                 perror_reply(425, "Can't open passive connection");
2884                 return;
2885         }
2886         on = 1;
2887         if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2888                 syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2889
2890         (void) seteuid(0);
2891
2892 #ifdef IP_PORTRANGE
2893         if (ctrl_addr.su_family == AF_INET) {
2894             on = restricted_data_ports ? IP_PORTRANGE_HIGH
2895                                        : IP_PORTRANGE_DEFAULT;
2896
2897             if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2898                             &on, sizeof(on)) < 0)
2899                     goto pasv_error;
2900         }
2901 #endif
2902 #ifdef IPV6_PORTRANGE
2903         if (ctrl_addr.su_family == AF_INET6) {
2904             on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2905                                        : IPV6_PORTRANGE_DEFAULT;
2906
2907             if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2908                             &on, sizeof(on)) < 0)
2909                     goto pasv_error;
2910         }
2911 #endif
2912
2913         pasv_addr = ctrl_addr;
2914         pasv_addr.su_port = 0;
2915         if (bind(pdata, (struct sockaddr *)&pasv_addr, pasv_addr.su_len) < 0)
2916                 goto pasv_error;
2917
2918         (void) seteuid(pw->pw_uid);
2919
2920         len = sizeof(pasv_addr);
2921         if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2922                 goto pasv_error;
2923         if (listen(pdata, 1) < 0)
2924                 goto pasv_error;
2925         if (pasv_addr.su_family == AF_INET)
2926                 a = (char *) &pasv_addr.su_sin.sin_addr;
2927         else if (pasv_addr.su_family == AF_INET6 &&
2928                  IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr))
2929                 a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
2930         else
2931                 goto pasv_error;
2932
2933         p = (char *) &pasv_addr.su_port;
2934
2935 #define UC(b) (((int) b) & 0xff)
2936
2937         reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
2938                 UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
2939         return;
2940
2941 pasv_error:
2942         (void) seteuid(pw->pw_uid);
2943         (void) close(pdata);
2944         pdata = -1;
2945         perror_reply(425, "Can't open passive connection");
2946         return;
2947 }
2948
2949 /*
2950  * Long Passive defined in RFC 1639.
2951  *     228 Entering Long Passive Mode
2952  *         (af, hal, h1, h2, h3,..., pal, p1, p2...)
2953  */
2954
2955 void
2956 long_passive(char *cmd, int pf)
2957 {
2958         socklen_t len;
2959         int on;
2960         char *p, *a;
2961
2962         if (pdata >= 0)         /* close old port if one set */
2963                 close(pdata);
2964
2965         if (pf != PF_UNSPEC) {
2966                 if (ctrl_addr.su_family != pf) {
2967                         switch (ctrl_addr.su_family) {
2968                         case AF_INET:
2969                                 pf = 1;
2970                                 break;
2971                         case AF_INET6:
2972                                 pf = 2;
2973                                 break;
2974                         default:
2975                                 pf = 0;
2976                                 break;
2977                         }
2978                         /*
2979                          * XXX
2980                          * only EPRT/EPSV ready clients will understand this
2981                          */
2982                         if (strcmp(cmd, "EPSV") == 0 && pf) {
2983                                 reply(522, "Network protocol mismatch, "
2984                                         "use (%d)", pf);
2985                         } else
2986                                 reply(501, "Network protocol mismatch."); /*XXX*/
2987
2988                         return;
2989                 }
2990         }
2991
2992         pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2993         if (pdata < 0) {
2994                 perror_reply(425, "Can't open passive connection");
2995                 return;
2996         }
2997         on = 1;
2998         if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2999                 syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
3000
3001         (void) seteuid(0);
3002
3003         pasv_addr = ctrl_addr;
3004         pasv_addr.su_port = 0;
3005         len = pasv_addr.su_len;
3006
3007 #ifdef IP_PORTRANGE
3008         if (ctrl_addr.su_family == AF_INET) {
3009             on = restricted_data_ports ? IP_PORTRANGE_HIGH
3010                                        : IP_PORTRANGE_DEFAULT;
3011
3012             if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
3013                             &on, sizeof(on)) < 0)
3014                     goto pasv_error;
3015         }
3016 #endif
3017 #ifdef IPV6_PORTRANGE
3018         if (ctrl_addr.su_family == AF_INET6) {
3019             on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
3020                                        : IPV6_PORTRANGE_DEFAULT;
3021
3022             if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
3023                             &on, sizeof(on)) < 0)
3024                     goto pasv_error;
3025         }
3026 #endif
3027
3028         if (bind(pdata, (struct sockaddr *)&pasv_addr, len) < 0)
3029                 goto pasv_error;
3030
3031         (void) seteuid(pw->pw_uid);
3032
3033         if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
3034                 goto pasv_error;
3035         if (listen(pdata, 1) < 0)
3036                 goto pasv_error;
3037
3038 #define UC(b) (((int) b) & 0xff)
3039
3040         if (strcmp(cmd, "LPSV") == 0) {
3041                 p = (char *)&pasv_addr.su_port;
3042                 switch (pasv_addr.su_family) {
3043                 case AF_INET:
3044                         a = (char *) &pasv_addr.su_sin.sin_addr;
3045                 v4_reply:
3046                         reply(228,
3047 "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3048                               4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3049                               2, UC(p[0]), UC(p[1]));
3050                         return;
3051                 case AF_INET6:
3052                         if (IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr)) {
3053                                 a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
3054                                 goto v4_reply;
3055                         }
3056                         a = (char *) &pasv_addr.su_sin6.sin6_addr;
3057                         reply(228,
3058 "Entering Long Passive Mode "
3059 "(%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3060                               6, 16, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3061                               UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
3062                               UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
3063                               UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
3064                               2, UC(p[0]), UC(p[1]));
3065                         return;
3066                 }
3067         } else if (strcmp(cmd, "EPSV") == 0) {
3068                 switch (pasv_addr.su_family) {
3069                 case AF_INET:
3070                 case AF_INET6:
3071                         reply(229, "Entering Extended Passive Mode (|||%d|)",
3072                                 ntohs(pasv_addr.su_port));
3073                         return;
3074                 }
3075         } else {
3076                 /* more proper error code? */
3077         }
3078
3079 pasv_error:
3080         (void) seteuid(pw->pw_uid);
3081         (void) close(pdata);
3082         pdata = -1;
3083         perror_reply(425, "Can't open passive connection");
3084         return;
3085 }
3086
3087 /*
3088  * Generate unique name for file with basename "local"
3089  * and open the file in order to avoid possible races.
3090  * Try "local" first, then "local.1", "local.2" etc, up to "local.99".
3091  * Return descriptor to the file, set "name" to its name.
3092  *
3093  * Generates failure reply on error.
3094  */
3095 static int
3096 guniquefd(char *local, char **name)
3097 {
3098         static char new[MAXPATHLEN];
3099         struct stat st;
3100         char *cp;
3101         int count;
3102         int fd;
3103
3104         cp = strrchr(local, '/');
3105         if (cp)
3106                 *cp = '\0';
3107         if (stat(cp ? local : ".", &st) < 0) {
3108                 perror_reply(553, cp ? local : ".");
3109                 return (-1);
3110         }
3111         if (cp) {
3112                 /*
3113                  * Let not overwrite dirname with counter suffix.
3114                  * -4 is for /nn\0
3115                  * In this extreme case dot won't be put in front of suffix.
3116                  */
3117                 if (strlen(local) > sizeof(new) - 4) {
3118                         reply(553, "Pathname too long.");
3119                         return (-1);
3120                 }
3121                 *cp = '/';
3122         }
3123         /* -4 is for the .nn<null> we put on the end below */
3124         (void) snprintf(new, sizeof(new) - 4, "%s", local);
3125         cp = new + strlen(new);
3126         /*
3127          * Don't generate dotfile unless requested explicitly.
3128          * This covers the case when basename gets truncated off
3129          * by buffer size.
3130          */
3131         if (cp > new && cp[-1] != '/')
3132                 *cp++ = '.';
3133         for (count = 0; count < 100; count++) {
3134                 /* At count 0 try unmodified name */
3135                 if (count)
3136                         (void)sprintf(cp, "%d", count);
3137                 if ((fd = open(count ? new : local,
3138                     O_RDWR | O_CREAT | O_EXCL, 0666)) >= 0) {
3139                         *name = count ? new : local;
3140                         return (fd);
3141                 }
3142                 if (errno != EEXIST) {
3143                         perror_reply(553, count ? new : local);
3144                         return (-1);
3145                 }
3146         }
3147         reply(452, "Unique file name cannot be created.");
3148         return (-1);
3149 }
3150
3151 /*
3152  * Format and send reply containing system error number.
3153  */
3154 void
3155 perror_reply(int code, char *string)
3156 {
3157
3158         reply(code, "%s: %s.", string, strerror(errno));
3159 }
3160
3161 static char *onefile[] = {
3162         "",
3163         0
3164 };
3165
3166 void
3167 send_file_list(char *whichf)
3168 {
3169         struct stat st;
3170         DIR *dirp = NULL;
3171         struct dirent *dir;
3172         FILE *dout = NULL;
3173         char **dirlist, *dirname;
3174         int simple = 0;
3175         int freeglob = 0;
3176         glob_t gl;
3177
3178         if (strpbrk(whichf, "~{[*?") != NULL) {
3179                 int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
3180
3181                 memset(&gl, 0, sizeof(gl));
3182                 gl.gl_matchc = MAXGLOBARGS;
3183                 flags |= GLOB_LIMIT;
3184                 freeglob = 1;
3185                 if (glob(whichf, flags, 0, &gl)) {
3186                         reply(550, "No matching files found.");
3187                         goto out;
3188                 } else if (gl.gl_pathc == 0) {
3189                         errno = ENOENT;
3190                         perror_reply(550, whichf);
3191                         goto out;
3192                 }
3193                 dirlist = gl.gl_pathv;
3194         } else {
3195                 onefile[0] = whichf;
3196                 dirlist = onefile;
3197                 simple = 1;
3198         }
3199
3200         while ((dirname = *dirlist++)) {
3201                 if (stat(dirname, &st) < 0) {
3202                         /*
3203                          * If user typed "ls -l", etc, and the client
3204                          * used NLST, do what the user meant.
3205                          */
3206                         if (dirname[0] == '-' && *dirlist == NULL &&
3207                             dout == NULL)
3208                                 retrieve(_PATH_LS " %s", dirname);
3209                         else
3210                                 perror_reply(550, whichf);
3211                         goto out;
3212                 }
3213
3214                 if (S_ISREG(st.st_mode)) {
3215                         if (dout == NULL) {
3216                                 dout = dataconn("file list", -1, "w");
3217                                 if (dout == NULL)
3218                                         goto out;
3219                                 STARTXFER;
3220                         }
3221                         START_UNSAFE;
3222                         fprintf(dout, "%s%s\n", dirname,
3223                                 type == TYPE_A ? "\r" : "");
3224                         END_UNSAFE;
3225                         if (ferror(dout))
3226                                 goto data_err;
3227                         byte_count += strlen(dirname) +
3228                                       (type == TYPE_A ? 2 : 1);
3229                         CHECKOOB(goto abrt);
3230                         continue;
3231                 } else if (!S_ISDIR(st.st_mode))
3232                         continue;
3233
3234                 if ((dirp = opendir(dirname)) == NULL)
3235                         continue;
3236
3237                 while ((dir = readdir(dirp)) != NULL) {
3238                         char nbuf[MAXPATHLEN];
3239
3240                         CHECKOOB(goto abrt);
3241
3242                         if (dir->d_name[0] == '.' && dir->d_namlen == 1)
3243                                 continue;
3244                         if (dir->d_name[0] == '.' && dir->d_name[1] == '.' &&
3245                             dir->d_namlen == 2)
3246                                 continue;
3247
3248                         snprintf(nbuf, sizeof(nbuf),
3249                                 "%s/%s", dirname, dir->d_name);
3250
3251                         /*
3252                          * We have to do a stat to insure it's
3253                          * not a directory or special file.
3254                          */
3255                         if (simple || (stat(nbuf, &st) == 0 &&
3256                             S_ISREG(st.st_mode))) {
3257                                 if (dout == NULL) {
3258                                         dout = dataconn("file list", -1, "w");
3259                                         if (dout == NULL)
3260                                                 goto out;
3261                                         STARTXFER;
3262                                 }
3263                                 START_UNSAFE;
3264                                 if (nbuf[0] == '.' && nbuf[1] == '/')
3265                                         fprintf(dout, "%s%s\n", &nbuf[2],
3266                                                 type == TYPE_A ? "\r" : "");
3267                                 else
3268                                         fprintf(dout, "%s%s\n", nbuf,
3269                                                 type == TYPE_A ? "\r" : "");
3270                                 END_UNSAFE;
3271                                 if (ferror(dout))
3272                                         goto data_err;
3273                                 byte_count += strlen(nbuf) +
3274                                               (type == TYPE_A ? 2 : 1);
3275                                 CHECKOOB(goto abrt);
3276                         }
3277                 }
3278                 (void) closedir(dirp);
3279                 dirp = NULL;
3280         }
3281
3282         if (dout == NULL)
3283                 reply(550, "No files found.");
3284         else if (ferror(dout))
3285 data_err:       perror_reply(550, "Data connection");
3286         else
3287                 reply(226, "Transfer complete.");
3288 out:
3289         if (dout) {
3290                 ENDXFER;
3291 abrt:
3292                 (void) fclose(dout);
3293                 data = -1;
3294                 pdata = -1;
3295         }
3296         if (dirp)
3297                 (void) closedir(dirp);
3298         if (freeglob) {
3299                 freeglob = 0;
3300                 globfree(&gl);
3301         }
3302 }
3303
3304 void
3305 reapchild(int signo)
3306 {
3307         while (waitpid(-1, NULL, WNOHANG) > 0);
3308 }
3309
3310 #ifdef OLD_SETPROCTITLE
3311 /*
3312  * Clobber argv so ps will show what we're doing.  (Stolen from sendmail.)
3313  * Warning, since this is usually started from inetd.conf, it often doesn't
3314  * have much of an environment or arglist to overwrite.
3315  */
3316 void
3317 setproctitle(const char *fmt, ...)
3318 {
3319         int i;
3320         va_list ap;
3321         char *p, *bp, ch;
3322         char buf[LINE_MAX];
3323
3324         va_start(ap, fmt);
3325         (void)vsnprintf(buf, sizeof(buf), fmt, ap);
3326
3327         /* make ps print our process name */
3328         p = Argv[0];
3329         *p++ = '-';
3330
3331         i = strlen(buf);
3332         if (i > LastArgv - p - 2) {
3333                 i = LastArgv - p - 2;
3334                 buf[i] = '\0';
3335         }
3336         bp = buf;
3337         while (ch = *bp++)
3338                 if (ch != '\n' && ch != '\r')
3339                         *p++ = ch;
3340         while (p < LastArgv)
3341                 *p++ = ' ';
3342 }
3343 #endif /* OLD_SETPROCTITLE */
3344
3345 static void
3346 appendf(char **strp, char *fmt, ...)
3347 {
3348         va_list ap;
3349         char *ostr, *p;
3350
3351         va_start(ap, fmt);
3352         vasprintf(&p, fmt, ap);
3353         va_end(ap);
3354         if (p == NULL)
3355                 fatalerror("Ran out of memory.");
3356         if (*strp == NULL)
3357                 *strp = p;
3358         else {
3359                 ostr = *strp;
3360                 asprintf(strp, "%s%s", ostr, p);
3361                 if (*strp == NULL)
3362                         fatalerror("Ran out of memory.");
3363                 free(ostr);
3364         }
3365 }
3366
3367 static void
3368 logcmd(char *cmd, char *file1, char *file2, off_t cnt)
3369 {
3370         char *msg = NULL;
3371         char wd[MAXPATHLEN + 1];
3372
3373         if (logging <= 1)
3374                 return;
3375
3376         if (getcwd(wd, sizeof(wd) - 1) == NULL)
3377                 strcpy(wd, strerror(errno));
3378
3379         appendf(&msg, "%s", cmd);
3380         if (file1)
3381                 appendf(&msg, " %s", file1);
3382         if (file2)
3383                 appendf(&msg, " %s", file2);
3384         if (cnt >= 0)
3385                 appendf(&msg, " = %jd bytes", (intmax_t)cnt);
3386         appendf(&msg, " (wd: %s", wd);
3387         if (guest || dochroot)
3388                 appendf(&msg, "; chrooted");
3389         appendf(&msg, ")");
3390         syslog(LOG_INFO, "%s", msg);
3391         free(msg);
3392 }
3393
3394 static void
3395 logxfer(char *name, off_t size, time_t start)
3396 {
3397         char buf[MAXPATHLEN + 1024];
3398         char path[MAXPATHLEN + 1];
3399         time_t now;
3400
3401         if (statfd >= 0) {
3402                 time(&now);
3403                 if (realpath(name, path) == NULL) {
3404                         syslog(LOG_NOTICE, "realpath failed on %s: %m", path);
3405                         return;
3406                 }
3407                 snprintf(buf, sizeof(buf), "%.20s!%s!%s!%s!%jd!%ld\n",
3408                         ctime(&now)+4, ident, remotehost,
3409                         path, (intmax_t)size,
3410                         (long)(now - start + (now == start)));
3411                 write(statfd, buf, strlen(buf));
3412         }
3413 }
3414
3415 static char *
3416 doublequote(char *s)
3417 {
3418         int n;
3419         char *p, *s2;
3420
3421         for (p = s, n = 0; *p; p++)
3422                 if (*p == '"')
3423                         n++;
3424
3425         if ((s2 = malloc(p - s + n + 1)) == NULL)
3426                 return (NULL);
3427
3428         for (p = s2; *s; s++, p++) {
3429                 if ((*p = *s) == '"')
3430                         *(++p) = '"';
3431         }
3432         *p = '\0';
3433
3434         return (s2);
3435 }
3436
3437 /* setup server socket for specified address family */
3438 /* if af is PF_UNSPEC more than one socket may be returned */
3439 /* the returned list is dynamically allocated, so caller needs to free it */
3440 static int *
3441 socksetup(int af, char *bindname, const char *bindport)
3442 {
3443         struct addrinfo hints, *res, *r;
3444         int error, maxs, *s, *socks;
3445         const int on = 1;
3446
3447         memset(&hints, 0, sizeof(hints));
3448         hints.ai_flags = AI_PASSIVE;
3449         hints.ai_family = af;
3450         hints.ai_socktype = SOCK_STREAM;
3451         error = getaddrinfo(bindname, bindport, &hints, &res);
3452         if (error) {
3453                 syslog(LOG_ERR, "%s", gai_strerror(error));
3454                 if (error == EAI_SYSTEM)
3455                         syslog(LOG_ERR, "%s", strerror(errno));
3456                 return NULL;
3457         }
3458
3459         /* Count max number of sockets we may open */
3460         for (maxs = 0, r = res; r; r = r->ai_next, maxs++)
3461                 ;
3462         socks = malloc((maxs + 1) * sizeof(int));
3463         if (!socks) {
3464                 freeaddrinfo(res);
3465                 syslog(LOG_ERR, "couldn't allocate memory for sockets");
3466                 return NULL;
3467         }
3468
3469         *socks = 0;   /* num of sockets counter at start of array */
3470         s = socks + 1;
3471         for (r = res; r; r = r->ai_next) {
3472                 *s = socket(r->ai_family, r->ai_socktype, r->ai_protocol);
3473                 if (*s < 0) {
3474                         syslog(LOG_DEBUG, "control socket: %m");
3475                         continue;
3476                 }
3477                 if (setsockopt(*s, SOL_SOCKET, SO_REUSEADDR,
3478                     &on, sizeof(on)) < 0)
3479                         syslog(LOG_WARNING,
3480                             "control setsockopt (SO_REUSEADDR): %m");
3481                 if (r->ai_family == AF_INET6) {
3482                         if (setsockopt(*s, IPPROTO_IPV6, IPV6_V6ONLY,
3483                             &on, sizeof(on)) < 0)
3484                                 syslog(LOG_WARNING,
3485                                     "control setsockopt (IPV6_V6ONLY): %m");
3486                 }
3487                 if (bind(*s, r->ai_addr, r->ai_addrlen) < 0) {
3488                         syslog(LOG_DEBUG, "control bind: %m");
3489                         close(*s);
3490                         continue;
3491                 }
3492                 (*socks)++;
3493                 s++;
3494         }
3495
3496         if (res)
3497                 freeaddrinfo(res);
3498
3499         if (*socks == 0) {
3500                 syslog(LOG_ERR, "control socket: Couldn't bind to any socket");
3501                 free(socks);
3502                 return NULL;
3503         }
3504         return(socks);
3505 }