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 #include "blacklist_client.h"
  97 #include "pathnames.h"
  98 #include "extern.h"
  99
 100 #include <stdarg.h>
 101
 102 static char version[] = "Version 6.00LS";
 103 #undef main
 104
 105 union sockunion ctrl_addr;
 106 union sockunion data_source;
 107 union sockunion data_dest;
 108 union sockunion his_addr;
 109 union sockunion pasv_addr;
 110
 111 int     daemon_mode;
 112 int     data;
 113 int     dataport;
 114 int     hostinfo = 1;   /* print host-specific info in messages */
 115 int     logged_in;
 116 struct  passwd *pw;
 117 char    *homedir;
 118 int     ftpdebug;
 119 int     timeout = 900;    /* timeout after 15 minutes of inactivity */
 120 int     maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */
 121 int     logging;
 122 int     restricted_data_ports = 1;
 123 int     paranoid = 1;     /* be extra careful about security */
 124 int     anon_only = 0;    /* Only anonymous ftp allowed */
 125 int     assumeutf8 = 0;   /* Assume that server file names are in UTF-8 */
 126 int     guest;
 127 int     dochroot;
 128 char    *chrootdir;
 129 int     dowtmp = 1;
 130 int     stats;
 131 int     statfd = -1;
 132 int     type;
 133 int     form;
 134 int     stru;                   /* avoid C keyword */
 135 int     mode;
 136 int     usedefault = 1;         /* for data transfers */
 137 int     pdata = -1;             /* for passive mode */
 138 int     readonly = 0;           /* Server is in readonly mode.  */
 139 int     noepsv = 0;             /* EPSV command is disabled.    */
 140 int     noretr = 0;             /* RETR command is disabled.    */
 141 int     noguestretr = 0;        /* RETR command is disabled for anon users. */
 142 int     noguestmkd = 0;         /* MKD command is disabled for anon users. */
 143 int     noguestmod = 1;         /* anon users may not modify existing files. */
 144 int     use_blacklist = 0;
 145
 146 off_t   file_size;
 147 off_t   byte_count;
 148 #if !defined(CMASK) || CMASK == 0
 149 #undef CMASK
 150 #define CMASK 027
 151 #endif
 152 int     defumask = CMASK;               /* default umask value */
 153 char    tmpline[7];
 154 char    *hostname;
 155 int     epsvall = 0;
 156
 157 #ifdef VIRTUAL_HOSTING
 158 char    *ftpuser;
 159
 160 static struct ftphost {
 161         struct ftphost  *next;
 162         struct addrinfo *hostinfo;
 163         char            *hostname;
 164         char            *anonuser;
 165         char            *statfile;
 166         char            *welcome;
 167         char            *loginmsg;
 168 } *thishost, *firsthost;
 169
 170 #endif
 171 char    remotehost[NI_MAXHOST];
 172 char    *ident = NULL;
 173
 174 static char     wtmpid[20];
 175
 176 #ifdef USE_PAM
 177 static int      auth_pam(struct passwd**, const char*);
 178 pam_handle_t    *pamh = NULL;
 179 #endif
 180
 181 static struct opie      opiedata;
 182 static char             opieprompt[OPIE_CHALLENGE_MAX+1];
 183 static int              pwok;
 184
 185 char    *pid_file = NULL; /* means default location to pidfile(3) */
 186
 187 /*
 188  * Limit number of pathnames that glob can return.
 189  * A limit of 0 indicates the number of pathnames is unlimited.
 190  */
 191 #define MAXGLOBARGS     16384
 192 #
 193
 194 /*
 195  * Timeout intervals for retrying connections
 196  * to hosts that don't accept PORT cmds.  This
 197  * is a kludge, but given the problems with TCP...
 198  */
 199 #define SWAITMAX        90      /* wait at most 90 seconds */
 200 #define SWAITINT        5       /* interval between retries */
 201
 202 int     swaitmax = SWAITMAX;
 203 int     swaitint = SWAITINT;
 204
 205 #ifdef SETPROCTITLE
 206 #ifdef OLD_SETPROCTITLE
 207 char    **Argv = NULL;          /* pointer to argument vector */
 208 char    *LastArgv = NULL;       /* end of argv */
 209 #endif /* OLD_SETPROCTITLE */
 210 char    proctitle[LINE_MAX];    /* initial part of title */
 211 #endif /* SETPROCTITLE */
 212
 213 #define LOGCMD(cmd, file)               logcmd((cmd), (file), NULL, -1)
 214 #define LOGCMD2(cmd, file1, file2)      logcmd((cmd), (file1), (file2), -1)
 215 #define LOGBYTES(cmd, file, cnt)        logcmd((cmd), (file), NULL, (cnt))
 216
 217 static  volatile sig_atomic_t recvurg;
 218 static  int transflag;          /* NB: for debugging only */
 219
 220 #define STARTXFER       flagxfer(1)
 221 #define ENDXFER         flagxfer(0)
 222
 223 #define START_UNSAFE    maskurg(1)
 224 #define END_UNSAFE      maskurg(0)
 225
 226 /* It's OK to put an `else' clause after this macro. */
 227 #define CHECKOOB(action)                                                \
 228         if (recvurg) {                                                  \
 229                 recvurg = 0;                                            \
 230                 if (myoob()) {                                          \
 231                         ENDXFER;                                        \
 232                         action;                                         \
 233                 }                                                       \
 234         }
 235
 236 #ifdef VIRTUAL_HOSTING
 237 static void      inithosts(int);
 238 static void      selecthost(union sockunion *);
 239 #endif
 240 static void      ack(char *);
 241 static void      sigurg(int);
 242 static void      maskurg(int);
 243 static void      flagxfer(int);
 244 static int       myoob(void);
 245 static int       checkuser(char *, char *, int, char **, int *);
 246 static FILE     *dataconn(char *, off_t, char *);
 247 static void      dolog(struct sockaddr *);
 248 static void      end_login(void);
 249 static FILE     *getdatasock(char *);
 250 static int       guniquefd(char *, char **);
 251 static void      lostconn(int);
 252 static void      sigquit(int);
 253 static int       receive_data(FILE *, FILE *);
 254 static int       send_data(FILE *, FILE *, size_t, off_t, int);
 255 static struct passwd *
 256                  sgetpwnam(char *);
 257 static char     *sgetsave(char *);
 258 static void      reapchild(int);
 259 static void      appendf(char **, char *, ...) __printflike(2, 3);
 260 static void      logcmd(char *, char *, char *, off_t);
 261 static void      logxfer(char *, off_t, time_t);
 262 static char     *doublequote(char *);
 263 static int      *socksetup(int, char *, const char *);
 264
 265 int
 266 main(int argc, char *argv[], char **envp)
 267 {
 268         socklen_t addrlen;
 269         int ch, on = 1, tos, s = STDIN_FILENO;
 270         char *cp, line[LINE_MAX];
 271         FILE *fd;
 272         char    *bindname = NULL;
 273         const char *bindport = "ftp";
 274         int     family = AF_UNSPEC;
 275         struct sigaction sa;
 276
 277         tzset();                /* in case no timezone database in ~ftp */
 278         sigemptyset(&sa.sa_mask);
 279         sa.sa_flags = SA_RESTART;
 280
 281 #ifdef OLD_SETPROCTITLE
 282         /*
 283          *  Save start and extent of argv for setproctitle.
 284          */
 285         Argv = argv;
 286         while (*envp)
 287                 envp++;
 288         LastArgv = envp[-1] + strlen(envp[-1]);
 289 #endif /* OLD_SETPROCTITLE */
 290
 291         /*
 292          * Prevent diagnostic messages from appearing on stderr.
 293          * We run as a daemon or from inetd; in both cases, there's
 294          * more reason in logging to syslog.
 295          */
 296         (void) freopen(_PATH_DEVNULL, "w", stderr);
 297         opterr = 0;
 298
 299         /*
 300          * LOG_NDELAY sets up the logging connection immediately,
 301          * necessary for anonymous ftp's that chroot and can't do it later.
 302          */
 303         openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP);
 304
 305         while ((ch = getopt(argc, argv,
 306                             "468a:ABdDEhlmMoOp:P:rRSt:T:u:UvW")) != -1) {
 307                 switch (ch) {
 308                 case '4':
 309                         family = (family == AF_INET6) ? AF_UNSPEC : AF_INET;
 310                         break;
 311
 312                 case '6':
 313                         family = (family == AF_INET) ? AF_UNSPEC : AF_INET6;
 314                         break;
 315
 316                 case '8':
 317                         assumeutf8 = 1;
 318                         break;
 319
 320                 case 'a':
 321                         bindname = optarg;
 322                         break;
 323
 324                 case 'A':
 325                         anon_only = 1;
 326                         break;
 327
 328                 case 'B':
 329 #ifdef USE_BLACKLIST
 330                         use_blacklist = 1;
 331 #else
 332                         syslog(LOG_WARNING, "not compiled with USE_BLACKLIST support");
 333 #endif
 334                         break;
 335
 336                 case 'd':
 337                         ftpdebug++;
 338                         break;
 339
 340                 case 'D':
 341                         daemon_mode++;
 342                         break;
 343
 344                 case 'E':
 345                         noepsv = 1;
 346                         break;
 347
 348                 case 'h':
 349                         hostinfo = 0;
 350                         break;
 351
 352                 case 'l':
 353                         logging++;      /* > 1 == extra logging */
 354                         break;
 355
 356                 case 'm':
 357                         noguestmod = 0;
 358                         break;
 359
 360                 case 'M':
 361                         noguestmkd = 1;
 362                         break;
 363
 364                 case 'o':
 365                         noretr = 1;
 366                         break;
 367
 368                 case 'O':
 369                         noguestretr = 1;
 370                         break;
 371
 372                 case 'p':
 373                         pid_file = optarg;
 374                         break;
 375
 376                 case 'P':
 377                         bindport = optarg;
 378                         break;
 379
 380                 case 'r':
 381                         readonly = 1;
 382                         break;
 383
 384                 case 'R':
 385                         paranoid = 0;
 386                         break;
 387
 388                 case 'S':
 389                         stats++;
 390                         break;
 391
 392                 case 't':
 393                         timeout = atoi(optarg);
 394                         if (maxtimeout < timeout)
 395                                 maxtimeout = timeout;
 396                         break;
 397
 398                 case 'T':
 399                         maxtimeout = atoi(optarg);
 400                         if (timeout > maxtimeout)
 401                                 timeout = maxtimeout;
 402                         break;
 403
 404                 case 'u':
 405                     {
 406                         long val = 0;
 407
 408                         val = strtol(optarg, &optarg, 8);
 409                         if (*optarg != '\0' || val < 0)
 410                                 syslog(LOG_WARNING, "bad value for -u");
 411                         else
 412                                 defumask = val;
 413                         break;
 414                     }
 415                 case 'U':
 416                         restricted_data_ports = 0;
 417                         break;
 418
 419                 case 'v':
 420                         ftpdebug++;
 421                         break;
 422
 423                 case 'W':
 424                         dowtmp = 0;
 425                         break;
 426
 427                 default:
 428                         syslog(LOG_WARNING, "unknown flag -%c ignored", optopt);
 429                         break;
 430                 }
 431         }
 432
 433         if (daemon_mode) {
 434                 int *ctl_sock, fd, maxfd = -1, nfds, i;
 435                 fd_set defreadfds, readfds;
 436                 pid_t pid;
 437                 struct pidfh *pfh;
 438
 439                 if ((pfh = pidfile_open(pid_file, 0600, &pid)) == NULL) {
 440                         if (errno == EEXIST) {
 441                                 syslog(LOG_ERR, "%s already running, pid %d",
 442                                        getprogname(), (int)pid);
 443                                 exit(1);
 444                         }
 445                         syslog(LOG_WARNING, "pidfile_open: %m");
 446                 }
 447
 448                 /*
 449                  * Detach from parent.
 450                  */
 451                 if (daemon(1, 1) < 0) {
 452                         syslog(LOG_ERR, "failed to become a daemon");
 453                         exit(1);
 454                 }
 455
 456                 if (pfh != NULL && pidfile_write(pfh) == -1)
 457                         syslog(LOG_WARNING, "pidfile_write: %m");
 458
 459                 sa.sa_handler = reapchild;
 460                 (void)sigaction(SIGCHLD, &sa, NULL);
 461
 462 #ifdef VIRTUAL_HOSTING
 463                 inithosts(family);
 464 #endif
 465
 466                 /*
 467                  * Open a socket, bind it to the FTP port, and start
 468                  * listening.
 469                  */
 470                 ctl_sock = socksetup(family, bindname, bindport);
 471                 if (ctl_sock == NULL)
 472                         exit(1);
 473
 474                 FD_ZERO(&defreadfds);
 475                 for (i = 1; i <= *ctl_sock; i++) {
 476                         FD_SET(ctl_sock[i], &defreadfds);
 477                         if (listen(ctl_sock[i], 32) < 0) {
 478                                 syslog(LOG_ERR, "control listen: %m");
 479                                 exit(1);
 480                         }
 481                         if (maxfd < ctl_sock[i])
 482                                 maxfd = ctl_sock[i];
 483                 }
 484
 485                 /*
 486                  * Loop forever accepting connection requests and forking off
 487                  * children to handle them.
 488                  */
 489                 while (1) {
 490                         FD_COPY(&defreadfds, &readfds);
 491                         nfds = select(maxfd + 1, &readfds, NULL, NULL, 0);
 492                         if (nfds <= 0) {
 493                                 if (nfds < 0 && errno != EINTR)
 494                                         syslog(LOG_WARNING, "select: %m");
 495                                 continue;
 496                         }
 497
 498                         pid = -1;
 499                         for (i = 1; i <= *ctl_sock; i++)
 500                                 if (FD_ISSET(ctl_sock[i], &readfds)) {
 501                                         addrlen = sizeof(his_addr);
 502                                         fd = accept(ctl_sock[i],
 503                                             (struct sockaddr *)&his_addr,
 504                                             &addrlen);
 505                                         if (fd == -1) {
 506                                                 syslog(LOG_WARNING,
 507                                                        "accept: %m");
 508                                                 continue;
 509                                         }
 510                                         switch (pid = fork()) {
 511                                         case 0:
 512                                                 /* child */
 513                                                 (void) dup2(fd, s);
 514                                                 (void) dup2(fd, STDOUT_FILENO);
 515                                                 (void) close(fd);
 516                                                 for (i = 1; i <= *ctl_sock; i++)
 517                                                         close(ctl_sock[i]);
 518                                                 if (pfh != NULL)
 519                                                         pidfile_close(pfh);
 520                                                 goto gotchild;
 521                                         case -1:
 522                                                 syslog(LOG_WARNING, "fork: %m");
 523                                                 /* FALLTHROUGH */
 524                                         default:
 525                                                 close(fd);
 526                                         }
 527                                 }
 528                 }
 529         } else {
 530                 addrlen = sizeof(his_addr);
 531                 if (getpeername(s, (struct sockaddr *)&his_addr, &addrlen) < 0) {
 532                         syslog(LOG_ERR, "getpeername (%s): %m",argv[0]);
 533                         exit(1);
 534                 }
 535
 536 #ifdef VIRTUAL_HOSTING
 537                 if (his_addr.su_family == AF_INET6 &&
 538                     IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr))
 539                         family = AF_INET;
 540                 else
 541                         family = his_addr.su_family;
 542                 inithosts(family);
 543 #endif
 544         }
 545
 546 gotchild:
 547         sa.sa_handler = SIG_DFL;
 548         (void)sigaction(SIGCHLD, &sa, NULL);
 549
 550         sa.sa_handler = sigurg;
 551         sa.sa_flags = 0;                /* don't restart syscalls for SIGURG */
 552         (void)sigaction(SIGURG, &sa, NULL);
 553
 554         sigfillset(&sa.sa_mask);        /* block all signals in handler */
 555         sa.sa_flags = SA_RESTART;
 556         sa.sa_handler = sigquit;
 557         (void)sigaction(SIGHUP, &sa, NULL);
 558         (void)sigaction(SIGINT, &sa, NULL);
 559         (void)sigaction(SIGQUIT, &sa, NULL);
 560         (void)sigaction(SIGTERM, &sa, NULL);
 561
 562         sa.sa_handler = lostconn;
 563         (void)sigaction(SIGPIPE, &sa, NULL);
 564
 565         addrlen = sizeof(ctrl_addr);
 566         if (getsockname(s, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) {
 567                 syslog(LOG_ERR, "getsockname (%s): %m",argv[0]);
 568                 exit(1);
 569         }
 570         dataport = ntohs(ctrl_addr.su_port) - 1; /* as per RFC 959 */
 571 #ifdef VIRTUAL_HOSTING
 572         /* select our identity from virtual host table */
 573         selecthost(&ctrl_addr);
 574 #endif
 575 #ifdef IP_TOS
 576         if (ctrl_addr.su_family == AF_INET)
 577       {
 578         tos = IPTOS_LOWDELAY;
 579         if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
 580                 syslog(LOG_WARNING, "control setsockopt (IP_TOS): %m");
 581       }
 582 #endif
 583         /*
 584          * Disable Nagle on the control channel so that we don't have to wait
 585          * for peer's ACK before issuing our next reply.
 586          */
 587         if (setsockopt(s, IPPROTO_TCP, TCP_NODELAY, &on, sizeof(on)) < 0)
 588                 syslog(LOG_WARNING, "control setsockopt (TCP_NODELAY): %m");
 589
 590         data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1);
 591
 592         (void)snprintf(wtmpid, sizeof(wtmpid), "%xftpd", getpid());
 593
 594         /* Try to handle urgent data inline */
 595 #ifdef SO_OOBINLINE
 596         if (setsockopt(s, SOL_SOCKET, SO_OOBINLINE, &on, sizeof(on)) < 0)
 597                 syslog(LOG_WARNING, "control setsockopt (SO_OOBINLINE): %m");
 598 #endif
 599
 600 #ifdef  F_SETOWN
 601         if (fcntl(s, F_SETOWN, getpid()) == -1)
 602                 syslog(LOG_ERR, "fcntl F_SETOWN: %m");
 603 #endif
 604         dolog((struct sockaddr *)&his_addr);
 605         /*
 606          * Set up default state
 607          */
 608         data = -1;
 609         type = TYPE_A;
 610         form = FORM_N;
 611         stru = STRU_F;
 612         mode = MODE_S;
 613         tmpline[0] = '\0';
 614
 615         /* If logins are disabled, print out the message. */
 616         if ((fd = fopen(_PATH_NOLOGIN,"r")) != NULL) {
 617                 while (fgets(line, sizeof(line), fd) != NULL) {
 618                         if ((cp = strchr(line, '\n')) != NULL)
 619                                 *cp = '\0';
 620                         lreply(530, "%s", line);
 621                 }
 622                 (void) fflush(stdout);
 623                 (void) fclose(fd);
 624                 reply(530, "System not available.");
 625                 exit(0);
 626         }
 627 #ifdef VIRTUAL_HOSTING
 628         fd = fopen(thishost->welcome, "r");
 629 #else
 630         fd = fopen(_PATH_FTPWELCOME, "r");
 631 #endif
 632         if (fd != NULL) {
 633                 while (fgets(line, sizeof(line), fd) != NULL) {
 634                         if ((cp = strchr(line, '\n')) != NULL)
 635                                 *cp = '\0';
 636                         lreply(220, "%s", line);
 637                 }
 638                 (void) fflush(stdout);
 639                 (void) fclose(fd);
 640                 /* reply(220,) must follow */
 641         }
 642 #ifndef VIRTUAL_HOSTING
 643         if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
 644                 fatalerror("Ran out of memory.");
 645         if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
 646                 hostname[0] = '\0';
 647         hostname[MAXHOSTNAMELEN - 1] = '\0';
 648 #endif
 649         if (hostinfo)
 650                 reply(220, "%s FTP server (%s) ready.", hostname, version);
 651         else
 652                 reply(220, "FTP server ready.");
 653         BLACKLIST_INIT();
 654         for (;;)
 655                 (void) yyparse();
 656         /* NOTREACHED */
 657 }
 658
 659 static void
 660 lostconn(int signo)
 661 {
 662
 663         if (ftpdebug)
 664                 syslog(LOG_DEBUG, "lost connection");
 665         dologout(1);
 666 }
 667
 668 static void
 669 sigquit(int signo)
 670 {
 671
 672         syslog(LOG_ERR, "got signal %d", signo);
 673         dologout(1);
 674 }
 675
 676 #ifdef VIRTUAL_HOSTING
 677 /*
 678  * read in virtual host tables (if they exist)
 679  */
 680
 681 static void
 682 inithosts(int family)
 683 {
 684         int insert;
 685         size_t len;
 686         FILE *fp;
 687         char *cp, *mp, *line;
 688         char *hostname;
 689         char *vhost, *anonuser, *statfile, *welcome, *loginmsg;
 690         struct ftphost *hrp, *lhrp;
 691         struct addrinfo hints, *res, *ai;
 692
 693         /*
 694          * Fill in the default host information
 695          */
 696         if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
 697                 fatalerror("Ran out of memory.");
 698         if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
 699                 hostname[0] = '\0';
 700         hostname[MAXHOSTNAMELEN - 1] = '\0';
 701         if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
 702                 fatalerror("Ran out of memory.");
 703         hrp->hostname = hostname;
 704         hrp->hostinfo = NULL;
 705
 706         memset(&hints, 0, sizeof(hints));
 707         hints.ai_flags = AI_PASSIVE;
 708         hints.ai_family = family;
 709         hints.ai_socktype = SOCK_STREAM;
 710         if (getaddrinfo(hrp->hostname, NULL, &hints, &res) == 0)
 711                 hrp->hostinfo = res;
 712         hrp->statfile = _PATH_FTPDSTATFILE;
 713         hrp->welcome  = _PATH_FTPWELCOME;
 714         hrp->loginmsg = _PATH_FTPLOGINMESG;
 715         hrp->anonuser = "ftp";
 716         hrp->next = NULL;
 717         thishost = firsthost = lhrp = hrp;
 718         if ((fp = fopen(_PATH_FTPHOSTS, "r")) != NULL) {
 719                 int addrsize, gothost;
 720                 void *addr;
 721                 struct hostent *hp;
 722
 723                 while ((line = fgetln(fp, &len)) != NULL) {
 724                         int     i, hp_error;
 725
 726                         /* skip comments */
 727                         if (line[0] == '#')
 728                                 continue;
 729                         if (line[len - 1] == '\n') {
 730                                 line[len - 1] = '\0';
 731                                 mp = NULL;
 732                         } else {
 733                                 if ((mp = malloc(len + 1)) == NULL)
 734                                         fatalerror("Ran out of memory.");
 735                                 memcpy(mp, line, len);
 736                                 mp[len] = '\0';
 737                                 line = mp;
 738                         }
 739                         cp = strtok(line, " \t");
 740                         /* skip empty lines */
 741                         if (cp == NULL)
 742                                 goto nextline;
 743                         vhost = cp;
 744
 745                         /* set defaults */
 746                         anonuser = "ftp";
 747                         statfile = _PATH_FTPDSTATFILE;
 748                         welcome  = _PATH_FTPWELCOME;
 749                         loginmsg = _PATH_FTPLOGINMESG;
 750
 751                         /*
 752                          * Preparse the line so we can use its info
 753                          * for all the addresses associated with
 754                          * the virtual host name.
 755                          * Field 0, the virtual host name, is special:
 756                          * it's already parsed off and will be strdup'ed
 757                          * later, after we know its canonical form.
 758                          */
 759                         for (i = 1; i < 5 && (cp = strtok(NULL, " \t")); i++)
 760                                 if (*cp != '-' && (cp = strdup(cp)))
 761                                         switch (i) {
 762                                         case 1: /* anon user permissions */
 763                                                 anonuser = cp;
 764                                                 break;
 765                                         case 2: /* statistics file */
 766                                                 statfile = cp;
 767                                                 break;
 768                                         case 3: /* welcome message */
 769                                                 welcome  = cp;
 770                                                 break;
 771                                         case 4: /* login message */
 772                                                 loginmsg = cp;
 773                                                 break;
 774                                         default: /* programming error */
 775                                                 abort();
 776                                                 /* NOTREACHED */
 777                                         }
 778
 779                         hints.ai_flags = AI_PASSIVE;
 780                         hints.ai_family = family;
 781                         hints.ai_socktype = SOCK_STREAM;
 782                         if (getaddrinfo(vhost, NULL, &hints, &res) != 0)
 783                                 goto nextline;
 784                         for (ai = res; ai != NULL && ai->ai_addr != NULL;
 785                              ai = ai->ai_next) {
 786
 787                         gothost = 0;
 788                         for (hrp = firsthost; hrp != NULL; hrp = hrp->next) {
 789                                 struct addrinfo *hi;
 790
 791                                 for (hi = hrp->hostinfo; hi != NULL;
 792                                      hi = hi->ai_next)
 793                                         if (hi->ai_addrlen == ai->ai_addrlen &&
 794                                             memcmp(hi->ai_addr,
 795                                                    ai->ai_addr,
 796                                                    ai->ai_addr->sa_len) == 0) {
 797                                                 gothost++;
 798                                                 break;
 799                                         }
 800                                 if (gothost)
 801                                         break;
 802                         }
 803                         if (hrp == NULL) {
 804                                 if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
 805                                         goto nextline;
 806                                 hrp->hostname = NULL;
 807                                 insert = 1;
 808                         } else {
 809                                 if (hrp->hostinfo && hrp->hostinfo != res)
 810                                         freeaddrinfo(hrp->hostinfo);
 811                                 insert = 0; /* host already in the chain */
 812                         }
 813                         hrp->hostinfo = res;
 814
 815                         /*
 816                          * determine hostname to use.
 817                          * force defined name if there is a valid alias
 818                          * otherwise fallback to primary hostname
 819                          */
 820                         /* XXX: getaddrinfo() can't do alias check */
 821                         switch(hrp->hostinfo->ai_family) {
 822                         case AF_INET:
 823                                 addr = &((struct sockaddr_in *)hrp->hostinfo->ai_addr)->sin_addr;
 824                                 addrsize = sizeof(struct in_addr);
 825                                 break;
 826                         case AF_INET6:
 827                                 addr = &((struct sockaddr_in6 *)hrp->hostinfo->ai_addr)->sin6_addr;
 828                                 addrsize = sizeof(struct in6_addr);
 829                                 break;
 830                         default:
 831                                 /* should not reach here */
 832                                 freeaddrinfo(hrp->hostinfo);
 833                                 if (insert)
 834                                         free(hrp); /*not in chain, can free*/
 835                                 else
 836                                         hrp->hostinfo = NULL; /*mark as blank*/
 837                                 goto nextline;
 838                                 /* NOTREACHED */
 839                         }
 840                         if ((hp = getipnodebyaddr(addr, addrsize,
 841                                                   hrp->hostinfo->ai_family,
 842                                                   &hp_error)) != NULL) {
 843                                 if (strcmp(vhost, hp->h_name) != 0) {
 844                                         if (hp->h_aliases == NULL)
 845                                                 vhost = hp->h_name;
 846                                         else {
 847                                                 i = 0;
 848                                                 while (hp->h_aliases[i] &&
 849                                                        strcmp(vhost, hp->h_aliases[i]) != 0)
 850                                                         ++i;
 851                                                 if (hp->h_aliases[i] == NULL)
 852                                                         vhost = hp->h_name;
 853                                         }
 854                                 }
 855                         }
 856                         if (hrp->hostname &&
 857                             strcmp(hrp->hostname, vhost) != 0) {
 858                                 free(hrp->hostname);
 859                                 hrp->hostname = NULL;
 860                         }
 861                         if (hrp->hostname == NULL &&
 862                             (hrp->hostname = strdup(vhost)) == NULL) {
 863                                 freeaddrinfo(hrp->hostinfo);
 864                                 hrp->hostinfo = NULL; /* mark as blank */
 865                                 if (hp)
 866                                         freehostent(hp);
 867                                 goto nextline;
 868                         }
 869                         hrp->anonuser = anonuser;
 870                         hrp->statfile = statfile;
 871                         hrp->welcome  = welcome;
 872                         hrp->loginmsg = loginmsg;
 873                         if (insert) {
 874                                 hrp->next  = NULL;
 875                                 lhrp->next = hrp;
 876                                 lhrp = hrp;
 877                         }
 878                         if (hp)
 879                                 freehostent(hp);
 880                       }
 881 nextline:
 882                         if (mp)
 883                                 free(mp);
 884                 }
 885                 (void) fclose(fp);
 886         }
 887 }
 888
 889 static void
 890 selecthost(union sockunion *su)
 891 {
 892         struct ftphost  *hrp;
 893         u_int16_t port;
 894 #ifdef INET6
 895         struct in6_addr *mapped_in6 = NULL;
 896 #endif
 897         struct addrinfo *hi;
 898
 899 #ifdef INET6
 900         /*
 901          * XXX IPv4 mapped IPv6 addr consideraton,
 902          * specified in rfc2373.
 903          */
 904         if (su->su_family == AF_INET6 &&
 905             IN6_IS_ADDR_V4MAPPED(&su->su_sin6.sin6_addr))
 906                 mapped_in6 = &su->su_sin6.sin6_addr;
 907 #endif
 908
 909         hrp = thishost = firsthost;     /* default */
 910         port = su->su_port;
 911         su->su_port = 0;
 912         while (hrp != NULL) {
 913             for (hi = hrp->hostinfo; hi != NULL; hi = hi->ai_next) {
 914                 if (memcmp(su, hi->ai_addr, hi->ai_addrlen) == 0) {
 915                         thishost = hrp;
 916                         goto found;
 917                 }
 918 #ifdef INET6
 919                 /* XXX IPv4 mapped IPv6 addr consideraton */
 920                 if (hi->ai_addr->sa_family == AF_INET && mapped_in6 != NULL &&
 921                     (memcmp(&mapped_in6->s6_addr[12],
 922                             &((struct sockaddr_in *)hi->ai_addr)->sin_addr,
 923                             sizeof(struct in_addr)) == 0)) {
 924                         thishost = hrp;
 925                         goto found;
 926                 }
 927 #endif
 928             }
 929             hrp = hrp->next;
 930         }
 931 found:
 932         su->su_port = port;
 933         /* setup static variables as appropriate */
 934         hostname = thishost->hostname;
 935         ftpuser = thishost->anonuser;
 936 }
 937 #endif
 938
 939 /*
 940  * Helper function for sgetpwnam().
 941  */
 942 static char *
 943 sgetsave(char *s)
 944 {
 945         char *new = malloc(strlen(s) + 1);
 946
 947         if (new == NULL) {
 948                 reply(421, "Ran out of memory.");
 949                 dologout(1);
 950                 /* NOTREACHED */
 951         }
 952         (void) strcpy(new, s);
 953         return (new);
 954 }
 955
 956 /*
 957  * Save the result of a getpwnam.  Used for USER command, since
 958  * the data returned must not be clobbered by any other command
 959  * (e.g., globbing).
 960  * NB: The data returned by sgetpwnam() will remain valid until
 961  * the next call to this function.  Its difference from getpwnam()
 962  * is that sgetpwnam() is known to be called from ftpd code only.
 963  */
 964 static struct passwd *
 965 sgetpwnam(char *name)
 966 {
 967         static struct passwd save;
 968         struct passwd *p;
 969
 970         if ((p = getpwnam(name)) == NULL)
 971                 return (p);
 972         if (save.pw_name) {
 973                 free(save.pw_name);
 974                 free(save.pw_passwd);
 975                 free(save.pw_class);
 976                 free(save.pw_gecos);
 977                 free(save.pw_dir);
 978                 free(save.pw_shell);
 979         }
 980         save = *p;
 981         save.pw_name = sgetsave(p->pw_name);
 982         save.pw_passwd = sgetsave(p->pw_passwd);
 983         save.pw_class = sgetsave(p->pw_class);
 984         save.pw_gecos = sgetsave(p->pw_gecos);
 985         save.pw_dir = sgetsave(p->pw_dir);
 986         save.pw_shell = sgetsave(p->pw_shell);
 987         return (&save);
 988 }
 989
 990 static int login_attempts;      /* number of failed login attempts */
 991 static int askpasswd;           /* had user command, ask for passwd */
 992 static char curname[MAXLOGNAME];        /* current USER name */
 993
 994 /*
 995  * USER command.
 996  * Sets global passwd pointer pw if named account exists and is acceptable;
 997  * sets askpasswd if a PASS command is expected.  If logged in previously,
 998  * need to reset state.  If name is "ftp" or "anonymous", the name is not in
 999  * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return.
1000  * If account doesn't exist, ask for passwd anyway.  Otherwise, check user
1001  * requesting login privileges.  Disallow anyone who does not have a standard
1002  * shell as returned by getusershell().  Disallow anyone mentioned in the file
1003  * _PATH_FTPUSERS to allow people such as root and uucp to be avoided.
1004  */
1005 void
1006 user(char *name)
1007 {
1008         int ecode;
1009         char *cp, *shell;
1010
1011         if (logged_in) {
1012                 if (guest) {
1013                         reply(530, "Can't change user from guest login.");
1014                         return;
1015                 } else if (dochroot) {
1016                         reply(530, "Can't change user from chroot user.");
1017                         return;
1018                 }
1019                 end_login();
1020         }
1021
1022         guest = 0;
1023 #ifdef VIRTUAL_HOSTING
1024         pw = sgetpwnam(thishost->anonuser);
1025 #else
1026         pw = sgetpwnam("ftp");
1027 #endif
1028         if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) {
1029                 if (checkuser(_PATH_FTPUSERS, "ftp", 0, NULL, &ecode) ||
1030                     (ecode != 0 && ecode != ENOENT))
1031                         reply(530, "User %s access denied.", name);
1032                 else if (checkuser(_PATH_FTPUSERS, "anonymous", 0, NULL, &ecode) ||
1033                     (ecode != 0 && ecode != ENOENT))
1034                         reply(530, "User %s access denied.", name);
1035                 else if (pw != NULL) {
1036                         guest = 1;
1037                         askpasswd = 1;
1038                         reply(331,
1039                         "Guest login ok, send your email address as password.");
1040                 } else
1041                         reply(530, "User %s unknown.", name);
1042                 if (!askpasswd && logging)
1043                         syslog(LOG_NOTICE,
1044                             "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost);
1045                 return;
1046         }
1047         if (anon_only != 0) {
1048                 reply(530, "Sorry, only anonymous ftp allowed.");
1049                 return;
1050         }
1051
1052         if ((pw = sgetpwnam(name))) {
1053                 if ((shell = pw->pw_shell) == NULL || *shell == 0)
1054                         shell = _PATH_BSHELL;
1055                 setusershell();
1056                 while ((cp = getusershell()) != NULL)
1057                         if (strcmp(cp, shell) == 0)
1058                                 break;
1059                 endusershell();
1060
1061                 if (cp == NULL ||
1062                     (checkuser(_PATH_FTPUSERS, name, 1, NULL, &ecode) ||
1063                     (ecode != 0 && ecode != ENOENT))) {
1064                         reply(530, "User %s access denied.", name);
1065                         if (logging)
1066                                 syslog(LOG_NOTICE,
1067                                     "FTP LOGIN REFUSED FROM %s, %s",
1068                                     remotehost, name);
1069                         pw = NULL;
1070                         return;
1071                 }
1072         }
1073         if (logging)
1074                 strncpy(curname, name, sizeof(curname)-1);
1075
1076         pwok = 0;
1077 #ifdef USE_PAM
1078         /* XXX Kluge! The conversation mechanism needs to be fixed. */
1079 #endif
1080         if (opiechallenge(&opiedata, name, opieprompt) == 0) {
1081                 pwok = (pw != NULL) &&
1082                        opieaccessfile(remotehost) &&
1083                        opiealways(pw->pw_dir);
1084                 reply(331, "Response to %s %s for %s.",
1085                       opieprompt, pwok ? "requested" : "required", name);
1086         } else {
1087                 pwok = 1;
1088                 reply(331, "Password required for %s.", name);
1089         }
1090         askpasswd = 1;
1091         /*
1092          * Delay before reading passwd after first failed
1093          * attempt to slow down passwd-guessing programs.
1094          */
1095         if (login_attempts)
1096                 sleep(login_attempts);
1097 }
1098
1099 /*
1100  * Check if a user is in the file "fname",
1101  * return a pointer to a malloc'd string with the rest
1102  * of the matching line in "residue" if not NULL.
1103  */
1104 static int
1105 checkuser(char *fname, char *name, int pwset, char **residue, int *ecode)
1106 {
1107         FILE *fd;
1108         int found = 0;
1109         size_t len;
1110         char *line, *mp, *p;
1111
1112         if (ecode != NULL)
1113                 *ecode = 0;
1114         if ((fd = fopen(fname, "r")) != NULL) {
1115                 while (!found && (line = fgetln(fd, &len)) != NULL) {
1116                         /* skip comments */
1117                         if (line[0] == '#')
1118                                 continue;
1119                         if (line[len - 1] == '\n') {
1120                                 line[len - 1] = '\0';
1121                                 mp = NULL;
1122                         } else {
1123                                 if ((mp = malloc(len + 1)) == NULL)
1124                                         fatalerror("Ran out of memory.");
1125                                 memcpy(mp, line, len);
1126                                 mp[len] = '\0';
1127                                 line = mp;
1128                         }
1129                         /* avoid possible leading and trailing whitespace */
1130                         p = strtok(line, " \t");
1131                         /* skip empty lines */
1132                         if (p == NULL)
1133                                 goto nextline;
1134                         /*
1135                          * if first chr is '@', check group membership
1136                          */
1137                         if (p[0] == '@') {
1138                                 int i = 0;
1139                                 struct group *grp;
1140
1141                                 if (p[1] == '\0') /* single @ matches anyone */
1142                                         found = 1;
1143                                 else {
1144                                         if ((grp = getgrnam(p+1)) == NULL)
1145                                                 goto nextline;
1146                                         /*
1147                                          * Check user's default group
1148                                          */
1149                                         if (pwset && grp->gr_gid == pw->pw_gid)
1150                                                 found = 1;
1151                                         /*
1152                                          * Check supplementary groups
1153                                          */
1154                                         while (!found && grp->gr_mem[i])
1155                                                 found = strcmp(name,
1156                                                         grp->gr_mem[i++])
1157                                                         == 0;
1158                                 }
1159                         }
1160                         /*
1161                          * Otherwise, just check for username match
1162                          */
1163                         else
1164                                 found = strcmp(p, name) == 0;
1165                         /*
1166                          * Save the rest of line to "residue" if matched
1167                          */
1168                         if (found && residue) {
1169                                 if ((p = strtok(NULL, "")) != NULL)
1170                                         p += strspn(p, " \t");
1171                                 if (p && *p) {
1172                                         if ((*residue = strdup(p)) == NULL)
1173                                                 fatalerror("Ran out of memory.");
1174                                 } else
1175                                         *residue = NULL;
1176                         }
1177 nextline:
1178                         if (mp)
1179                                 free(mp);
1180                 }
1181                 (void) fclose(fd);
1182         } else if (ecode != NULL)
1183                 *ecode = errno;
1184         return (found);
1185 }
1186
1187 /*
1188  * Terminate login as previous user, if any, resetting state;
1189  * used when USER command is given or login fails.
1190  */
1191 static void
1192 end_login(void)
1193 {
1194 #ifdef USE_PAM
1195         int e;
1196 #endif
1197
1198         (void) seteuid(0);
1199         if (logged_in && dowtmp)
1200                 ftpd_logwtmp(wtmpid, NULL, NULL);
1201         pw = NULL;
1202 #ifdef  LOGIN_CAP
1203         setusercontext(NULL, getpwuid(0), 0, LOGIN_SETALL & ~(LOGIN_SETLOGIN |
1204                        LOGIN_SETUSER | LOGIN_SETGROUP | LOGIN_SETPATH |
1205                        LOGIN_SETENV));
1206 #endif
1207 #ifdef USE_PAM
1208         if (pamh) {
1209                 if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS)
1210                         syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1211                 if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS)
1212                         syslog(LOG_ERR, "pam_close_session: %s", pam_strerror(pamh, e));
1213                 if ((e = pam_end(pamh, e)) != PAM_SUCCESS)
1214                         syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1215                 pamh = NULL;
1216         }
1217 #endif
1218         logged_in = 0;
1219         guest = 0;
1220         dochroot = 0;
1221 }
1222
1223 #ifdef USE_PAM
1224
1225 /*
1226  * the following code is stolen from imap-uw PAM authentication module and
1227  * login.c
1228  */
1229 #define COPY_STRING(s) (s ? strdup(s) : NULL)
1230
1231 struct cred_t {
1232         const char *uname;              /* user name */
1233         const char *pass;               /* password */
1234 };
1235 typedef struct cred_t cred_t;
1236
1237 static int
1238 auth_conv(int num_msg, const struct pam_message **msg,
1239           struct pam_response **resp, void *appdata)
1240 {
1241         int i;
1242         cred_t *cred = (cred_t *) appdata;
1243         struct pam_response *reply;
1244
1245         reply = calloc(num_msg, sizeof *reply);
1246         if (reply == NULL)
1247                 return PAM_BUF_ERR;
1248
1249         for (i = 0; i < num_msg; i++) {
1250                 switch (msg[i]->msg_style) {
1251                 case PAM_PROMPT_ECHO_ON:        /* assume want user name */
1252                         reply[i].resp_retcode = PAM_SUCCESS;
1253                         reply[i].resp = COPY_STRING(cred->uname);
1254                         /* PAM frees resp. */
1255                         break;
1256                 case PAM_PROMPT_ECHO_OFF:       /* assume want password */
1257                         reply[i].resp_retcode = PAM_SUCCESS;
1258                         reply[i].resp = COPY_STRING(cred->pass);
1259                         /* PAM frees resp. */
1260                         break;
1261                 case PAM_TEXT_INFO:
1262                 case PAM_ERROR_MSG:
1263                         reply[i].resp_retcode = PAM_SUCCESS;
1264                         reply[i].resp = NULL;
1265                         break;
1266                 default:                        /* unknown message style */
1267                         free(reply);
1268                         return PAM_CONV_ERR;
1269                 }
1270         }
1271
1272         *resp = reply;
1273         return PAM_SUCCESS;
1274 }
1275
1276 /*
1277  * Attempt to authenticate the user using PAM.  Returns 0 if the user is
1278  * authenticated, or 1 if not authenticated.  If some sort of PAM system
1279  * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
1280  * function returns -1.  This can be used as an indication that we should
1281  * fall back to a different authentication mechanism.
1282  */
1283 static int
1284 auth_pam(struct passwd **ppw, const char *pass)
1285 {
1286         const char *tmpl_user;
1287         const void *item;
1288         int rval;
1289         int e;
1290         cred_t auth_cred = { (*ppw)->pw_name, pass };
1291         struct pam_conv conv = { &auth_conv, &auth_cred };
1292
1293         e = pam_start("ftpd", (*ppw)->pw_name, &conv, &pamh);
1294         if (e != PAM_SUCCESS) {
1295                 /*
1296                  * In OpenPAM, it's OK to pass NULL to pam_strerror()
1297                  * if context creation has failed in the first place.
1298                  */
1299                 syslog(LOG_ERR, "pam_start: %s", pam_strerror(NULL, e));
1300                 return -1;
1301         }
1302
1303         e = pam_set_item(pamh, PAM_RHOST, remotehost);
1304         if (e != PAM_SUCCESS) {
1305                 syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
1306                         pam_strerror(pamh, e));
1307                 if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1308                         syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1309                 }
1310                 pamh = NULL;
1311                 return -1;
1312         }
1313
1314         e = pam_authenticate(pamh, 0);
1315         switch (e) {
1316         case PAM_SUCCESS:
1317                 /*
1318                  * With PAM we support the concept of a "template"
1319                  * user.  The user enters a login name which is
1320                  * authenticated by PAM, usually via a remote service
1321                  * such as RADIUS or TACACS+.  If authentication
1322                  * succeeds, a different but related "template" name
1323                  * is used for setting the credentials, shell, and
1324                  * home directory.  The name the user enters need only
1325                  * exist on the remote authentication server, but the
1326                  * template name must be present in the local password
1327                  * database.
1328                  *
1329                  * This is supported by two various mechanisms in the
1330                  * individual modules.  However, from the application's
1331                  * point of view, the template user is always passed
1332                  * back as a changed value of the PAM_USER item.
1333                  */
1334                 if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
1335                     PAM_SUCCESS) {
1336                         tmpl_user = (const char *) item;
1337                         if (strcmp((*ppw)->pw_name, tmpl_user) != 0)
1338                                 *ppw = getpwnam(tmpl_user);
1339                 } else
1340                         syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
1341                             pam_strerror(pamh, e));
1342                 rval = 0;
1343                 break;
1344
1345         case PAM_AUTH_ERR:
1346         case PAM_USER_UNKNOWN:
1347         case PAM_MAXTRIES:
1348                 rval = 1;
1349                 break;
1350
1351         default:
1352                 syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
1353                 rval = -1;
1354                 break;
1355         }
1356
1357         if (rval == 0) {
1358                 e = pam_acct_mgmt(pamh, 0);
1359                 if (e != PAM_SUCCESS) {
1360                         syslog(LOG_ERR, "pam_acct_mgmt: %s",
1361                                                 pam_strerror(pamh, e));
1362                         rval = 1;
1363                 }
1364         }
1365
1366         if (rval != 0) {
1367                 if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1368                         syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1369                 }
1370                 pamh = NULL;
1371         }
1372         return rval;
1373 }
1374
1375 #endif /* USE_PAM */
1376
1377 void
1378 pass(char *passwd)
1379 {
1380         int rval, ecode;
1381         FILE *fd;
1382 #ifdef  LOGIN_CAP
1383         login_cap_t *lc = NULL;
1384 #endif
1385 #ifdef USE_PAM
1386         int e;
1387 #endif
1388         char *residue = NULL;
1389         char *xpasswd;
1390
1391         if (logged_in || askpasswd == 0) {
1392                 reply(503, "Login with USER first.");
1393                 return;
1394         }
1395         askpasswd = 0;
1396         if (!guest) {           /* "ftp" is only account allowed no password */
1397                 if (pw == NULL) {
1398                         rval = 1;       /* failure below */
1399                         goto skip;
1400                 }
1401 #ifdef USE_PAM
1402                 rval = auth_pam(&pw, passwd);
1403                 if (rval >= 0) {
1404                         opieunlock();
1405                         goto skip;
1406                 }
1407 #endif
1408                 if (opieverify(&opiedata, passwd) == 0)
1409                         xpasswd = pw->pw_passwd;
1410                 else if (pwok) {
1411                         xpasswd = crypt(passwd, pw->pw_passwd);
1412                         if (passwd[0] == '\0' && pw->pw_passwd[0] != '\0')
1413                                 xpasswd = ":";
1414                 } else {
1415                         rval = 1;
1416                         goto skip;
1417                 }
1418                 rval = strcmp(pw->pw_passwd, xpasswd);
1419                 if (pw->pw_expire && time(NULL) >= pw->pw_expire)
1420                         rval = 1;       /* failure */
1421 skip:
1422                 /*
1423                  * If rval == 1, the user failed the authentication check
1424                  * above.  If rval == 0, either PAM or local authentication
1425                  * succeeded.
1426                  */
1427                 if (rval) {
1428                         reply(530, "Login incorrect.");
1429                         BLACKLIST_NOTIFY(BLACKLIST_AUTH_FAIL, STDIN_FILENO, "Login incorrect");
1430                         if (logging) {
1431                                 syslog(LOG_NOTICE,
1432                                     "FTP LOGIN FAILED FROM %s",
1433                                     remotehost);
1434                                 syslog(LOG_AUTHPRIV | LOG_NOTICE,
1435                                     "FTP LOGIN FAILED FROM %s, %s",
1436                                     remotehost, curname);
1437                         }
1438                         pw = NULL;
1439                         if (login_attempts++ >= 5) {
1440                                 syslog(LOG_NOTICE,
1441                                     "repeated login failures from %s",
1442                                     remotehost);
1443                                 exit(0);
1444                         }
1445                         return;
1446                 } else {
1447                         BLACKLIST_NOTIFY(BLACKLIST_AUTH_OK, STDIN_FILENO, "Login successful");
1448                 }
1449         }
1450         login_attempts = 0;             /* this time successful */
1451         if (setegid(pw->pw_gid) < 0) {
1452                 reply(550, "Can't set gid.");
1453                 return;
1454         }
1455         /* May be overridden by login.conf */
1456         (void) umask(defumask);
1457 #ifdef  LOGIN_CAP
1458         if ((lc = login_getpwclass(pw)) != NULL) {
1459                 char    remote_ip[NI_MAXHOST];
1460
1461                 if (getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
1462                         remote_ip, sizeof(remote_ip) - 1, NULL, 0,
1463                         NI_NUMERICHOST))
1464                                 *remote_ip = 0;
1465                 remote_ip[sizeof(remote_ip) - 1] = 0;
1466                 if (!auth_hostok(lc, remotehost, remote_ip)) {
1467                         syslog(LOG_INFO|LOG_AUTH,
1468                             "FTP LOGIN FAILED (HOST) as %s: permission denied.",
1469                             pw->pw_name);
1470                         reply(530, "Permission denied.");
1471                         pw = NULL;
1472                         return;
1473                 }
1474                 if (!auth_timeok(lc, time(NULL))) {
1475                         reply(530, "Login not available right now.");
1476                         pw = NULL;
1477                         return;
1478                 }
1479         }
1480         setusercontext(lc, pw, 0, LOGIN_SETALL &
1481                        ~(LOGIN_SETUSER | LOGIN_SETPATH | LOGIN_SETENV));
1482 #else
1483         setlogin(pw->pw_name);
1484         (void) initgroups(pw->pw_name, pw->pw_gid);
1485 #endif
1486
1487 #ifdef USE_PAM
1488         if (pamh) {
1489                 if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
1490                         syslog(LOG_ERR, "pam_open_session: %s", pam_strerror(pamh, e));
1491                 } else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED)) != PAM_SUCCESS) {
1492                         syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1493                 }
1494         }
1495 #endif
1496
1497         dochroot =
1498                 checkuser(_PATH_FTPCHROOT, pw->pw_name, 1, &residue, &ecode)
1499 #ifdef  LOGIN_CAP       /* Allow login.conf configuration as well */
1500                 || login_getcapbool(lc, "ftp-chroot", 0)
1501 #endif
1502         ;
1503         /*
1504          * It is possible that checkuser() failed to open the chroot file.
1505          * If this is the case, report that logins are un-available, since we
1506          * have no way of checking whether or not the user should be chrooted.
1507          * We ignore ENOENT since it is not required that this file be present.
1508          */
1509         if (ecode != 0 && ecode != ENOENT) {
1510                 reply(530, "Login not available right now.");
1511                 return;
1512         }
1513         chrootdir = NULL;
1514
1515         /* Disable wtmp logging when chrooting. */
1516         if (dochroot || guest)
1517                 dowtmp = 0;
1518         if (dowtmp)
1519                 ftpd_logwtmp(wtmpid, pw->pw_name,
1520                     (struct sockaddr *)&his_addr);
1521         logged_in = 1;
1522
1523         if (guest && stats && statfd < 0)
1524 #ifdef VIRTUAL_HOSTING
1525                 statfd = open(thishost->statfile, O_WRONLY|O_APPEND);
1526 #else
1527                 statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND);
1528 #endif
1529                 if (statfd < 0)
1530                         stats = 0;
1531
1532         /*
1533          * For a chrooted local user,
1534          * a) see whether ftpchroot(5) specifies a chroot directory,
1535          * b) extract the directory pathname from the line,
1536          * c) expand it to the absolute pathname if necessary.
1537          */
1538         if (dochroot && residue &&
1539             (chrootdir = strtok(residue, " \t")) != NULL) {
1540                 if (chrootdir[0] != '/')
1541                         asprintf(&chrootdir, "%s/%s", pw->pw_dir, chrootdir);
1542                 else
1543                         chrootdir = strdup(chrootdir); /* make it permanent */
1544                 if (chrootdir == NULL)
1545                         fatalerror("Ran out of memory.");
1546         }
1547         if (guest || dochroot) {
1548                 /*
1549                  * If no chroot directory set yet, use the login directory.
1550                  * Copy it so it can be modified while pw->pw_dir stays intact.
1551                  */
1552                 if (chrootdir == NULL &&
1553                     (chrootdir = strdup(pw->pw_dir)) == NULL)
1554                         fatalerror("Ran out of memory.");
1555                 /*
1556                  * Check for the "/chroot/./home" syntax,
1557                  * separate the chroot and home directory pathnames.
1558                  */
1559                 if ((homedir = strstr(chrootdir, "/./")) != NULL) {
1560                         *(homedir++) = '\0';    /* wipe '/' */
1561                         homedir++;              /* skip '.' */
1562                 } else {
1563                         /*
1564                          * We MUST do a chdir() after the chroot. Otherwise
1565                          * the old current directory will be accessible as "."
1566                          * outside the new root!
1567                          */
1568                         homedir = "/";
1569                 }
1570                 /*
1571                  * Finally, do chroot()
1572                  */
1573                 if (chroot(chrootdir) < 0) {
1574                         reply(550, "Can't change root.");
1575                         goto bad;
1576                 }
1577                 __FreeBSD_libc_enter_restricted_mode();
1578         } else  /* real user w/o chroot */
1579                 homedir = pw->pw_dir;
1580         /*
1581          * Set euid *before* doing chdir() so
1582          * a) the user won't be carried to a directory that he couldn't reach
1583          *    on his own due to no permission to upper path components,
1584          * b) NFS mounted homedirs w/restrictive permissions will be accessible
1585          *    (uid 0 has no root power over NFS if not mapped explicitly.)
1586          */
1587         if (seteuid(pw->pw_uid) < 0) {
1588                 reply(550, "Can't set uid.");
1589                 goto bad;
1590         }
1591         if (chdir(homedir) < 0) {
1592                 if (guest || dochroot) {
1593                         reply(550, "Can't change to base directory.");
1594                         goto bad;
1595                 } else {
1596                         if (chdir("/") < 0) {
1597                                 reply(550, "Root is inaccessible.");
1598                                 goto bad;
1599                         }
1600                         lreply(230, "No directory! Logging in with home=/.");
1601                 }
1602         }
1603
1604         /*
1605          * Display a login message, if it exists.
1606          * N.B. reply(230,) must follow the message.
1607          */
1608 #ifdef VIRTUAL_HOSTING
1609         fd = fopen(thishost->loginmsg, "r");
1610 #else
1611         fd = fopen(_PATH_FTPLOGINMESG, "r");
1612 #endif
1613         if (fd != NULL) {
1614                 char *cp, line[LINE_MAX];
1615
1616                 while (fgets(line, sizeof(line), fd) != NULL) {
1617                         if ((cp = strchr(line, '\n')) != NULL)
1618                                 *cp = '\0';
1619                         lreply(230, "%s", line);
1620                 }
1621                 (void) fflush(stdout);
1622                 (void) fclose(fd);
1623         }
1624         if (guest) {
1625                 if (ident != NULL)
1626                         free(ident);
1627                 ident = strdup(passwd);
1628                 if (ident == NULL)
1629                         fatalerror("Ran out of memory.");
1630
1631                 reply(230, "Guest login ok, access restrictions apply.");
1632 #ifdef SETPROCTITLE
1633 #ifdef VIRTUAL_HOSTING
1634                 if (thishost != firsthost)
1635                         snprintf(proctitle, sizeof(proctitle),
1636                                  "%s: anonymous(%s)/%s", remotehost, hostname,
1637                                  passwd);
1638                 else
1639 #endif
1640                         snprintf(proctitle, sizeof(proctitle),
1641                                  "%s: anonymous/%s", remotehost, passwd);
1642                 setproctitle("%s", proctitle);
1643 #endif /* SETPROCTITLE */
1644                 if (logging)
1645                         syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s",
1646                             remotehost, passwd);
1647         } else {
1648                 if (dochroot)
1649                         reply(230, "User %s logged in, "
1650                                    "access restrictions apply.", pw->pw_name);
1651                 else
1652                         reply(230, "User %s logged in.", pw->pw_name);
1653
1654 #ifdef SETPROCTITLE
1655                 snprintf(proctitle, sizeof(proctitle),
1656                          "%s: user/%s", remotehost, pw->pw_name);
1657                 setproctitle("%s", proctitle);
1658 #endif /* SETPROCTITLE */
1659                 if (logging)
1660                         syslog(LOG_INFO, "FTP LOGIN FROM %s as %s",
1661                             remotehost, pw->pw_name);
1662         }
1663         if (logging && (guest || dochroot))
1664                 syslog(LOG_INFO, "session root changed to %s", chrootdir);
1665 #ifdef  LOGIN_CAP
1666         login_close(lc);
1667 #endif
1668         if (residue)
1669                 free(residue);
1670         return;
1671 bad:
1672         /* Forget all about it... */
1673 #ifdef  LOGIN_CAP
1674         login_close(lc);
1675 #endif
1676         if (residue)
1677                 free(residue);
1678         end_login();
1679 }
1680
1681 void
1682 retrieve(char *cmd, char *name)
1683 {
1684         FILE *fin, *dout;
1685         struct stat st;
1686         int (*closefunc)(FILE *);
1687         time_t start;
1688         char line[BUFSIZ];
1689
1690         if (cmd == 0) {
1691                 fin = fopen(name, "r"), closefunc = fclose;
1692                 st.st_size = 0;
1693         } else {
1694                 (void) snprintf(line, sizeof(line), cmd, name);
1695                 name = line;
1696                 fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose;
1697                 st.st_size = -1;
1698                 st.st_blksize = BUFSIZ;
1699         }
1700         if (fin == NULL) {
1701                 if (errno != 0) {
1702                         perror_reply(550, name);
1703                         if (cmd == 0) {
1704                                 LOGCMD("get", name);
1705                         }
1706                 }
1707                 return;
1708         }
1709         byte_count = -1;
1710         if (cmd == 0) {
1711                 if (fstat(fileno(fin), &st) < 0) {
1712                         perror_reply(550, name);
1713                         goto done;
1714                 }
1715                 if (!S_ISREG(st.st_mode)) {
1716                         /*
1717                          * Never sending a raw directory is a workaround
1718                          * for buggy clients that will attempt to RETR
1719                          * a directory before listing it, e.g., Mozilla.
1720                          * Preventing a guest from getting irregular files
1721                          * is a simple security measure.
1722                          */
1723                         if (S_ISDIR(st.st_mode) || guest) {
1724                                 reply(550, "%s: not a plain file.", name);
1725                                 goto done;
1726                         }
1727                         st.st_size = -1;
1728                         /* st.st_blksize is set for all descriptor types */
1729                 }
1730         }
1731         if (restart_point) {
1732                 if (type == TYPE_A) {
1733                         off_t i, n;
1734                         int c;
1735
1736                         n = restart_point;
1737                         i = 0;
1738                         while (i++ < n) {
1739                                 if ((c=getc(fin)) == EOF) {
1740                                         perror_reply(550, name);
1741                                         goto done;
1742                                 }
1743                                 if (c == '\n')
1744                                         i++;
1745                         }
1746                 } else if (lseek(fileno(fin), restart_point, L_SET) < 0) {
1747                         perror_reply(550, name);
1748                         goto done;
1749                 }
1750         }
1751         dout = dataconn(name, st.st_size, "w");
1752         if (dout == NULL)
1753                 goto done;
1754         time(&start);
1755         send_data(fin, dout, st.st_blksize, st.st_size,
1756                   restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode));
1757         if (cmd == 0 && guest && stats && byte_count > 0)
1758                 logxfer(name, byte_count, start);
1759         (void) fclose(dout);
1760         data = -1;
1761         pdata = -1;
1762 done:
1763         if (cmd == 0)
1764                 LOGBYTES("get", name, byte_count);
1765         (*closefunc)(fin);
1766 }
1767
1768 void
1769 store(char *name, char *mode, int unique)
1770 {
1771         int fd;
1772         FILE *fout, *din;
1773         int (*closefunc)(FILE *);
1774
1775         if (*mode == 'a') {             /* APPE */
1776                 if (unique) {
1777                         /* Programming error */
1778                         syslog(LOG_ERR, "Internal: unique flag to APPE");
1779                         unique = 0;
1780                 }
1781                 if (guest && noguestmod) {
1782                         reply(550, "Appending to existing file denied.");
1783                         goto err;
1784                 }
1785                 restart_point = 0;      /* not affected by preceding REST */
1786         }
1787         if (unique)                     /* STOU overrides REST */
1788                 restart_point = 0;
1789         if (guest && noguestmod) {
1790                 if (restart_point) {    /* guest STOR w/REST */
1791                         reply(550, "Modifying existing file denied.");
1792                         goto err;
1793                 } else                  /* treat guest STOR as STOU */
1794                         unique = 1;
1795         }
1796
1797         if (restart_point)
1798                 mode = "r+";    /* so ASCII manual seek can work */
1799         if (unique) {
1800                 if ((fd = guniquefd(name, &name)) < 0)
1801                         goto err;
1802                 fout = fdopen(fd, mode);
1803         } else
1804                 fout = fopen(name, mode);
1805         closefunc = fclose;
1806         if (fout == NULL) {
1807                 perror_reply(553, name);
1808                 goto err;
1809         }
1810         byte_count = -1;
1811         if (restart_point) {
1812                 if (type == TYPE_A) {
1813                         off_t i, n;
1814                         int c;
1815
1816                         n = restart_point;
1817                         i = 0;
1818                         while (i++ < n) {
1819                                 if ((c=getc(fout)) == EOF) {
1820                                         perror_reply(550, name);
1821                                         goto done;
1822                                 }
1823                                 if (c == '\n')
1824                                         i++;
1825                         }
1826                         /*
1827                          * We must do this seek to "current" position
1828                          * because we are changing from reading to
1829                          * writing.
1830                          */
1831                         if (fseeko(fout, 0, SEEK_CUR) < 0) {
1832                                 perror_reply(550, name);
1833                                 goto done;
1834                         }
1835                 } else if (lseek(fileno(fout), restart_point, L_SET) < 0) {
1836                         perror_reply(550, name);
1837                         goto done;
1838                 }
1839         }
1840         din = dataconn(name, -1, "r");
1841         if (din == NULL)
1842                 goto done;
1843         if (receive_data(din, fout) == 0) {
1844                 if (unique)
1845                         reply(226, "Transfer complete (unique file name:%s).",
1846                             name);
1847                 else
1848                         reply(226, "Transfer complete.");
1849         }
1850         (void) fclose(din);
1851         data = -1;
1852         pdata = -1;
1853 done:
1854         LOGBYTES(*mode == 'a' ? "append" : "put", name, byte_count);
1855         (*closefunc)(fout);
1856         return;
1857 err:
1858         LOGCMD(*mode == 'a' ? "append" : "put" , name);
1859         return;
1860 }
1861
1862 static FILE *
1863 getdatasock(char *mode)
1864 {
1865         int on = 1, s, t, tries;
1866
1867         if (data >= 0)
1868                 return (fdopen(data, mode));
1869
1870         s = socket(data_dest.su_family, SOCK_STREAM, 0);
1871         if (s < 0)
1872                 goto bad;
1873         if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
1874                 syslog(LOG_WARNING, "data setsockopt (SO_REUSEADDR): %m");
1875         /* anchor socket to avoid multi-homing problems */
1876         data_source = ctrl_addr;
1877         data_source.su_port = htons(dataport);
1878         (void) seteuid(0);
1879         for (tries = 1; ; tries++) {
1880                 /*
1881                  * We should loop here since it's possible that
1882                  * another ftpd instance has passed this point and is
1883                  * trying to open a data connection in active mode now.
1884                  * Until the other connection is opened, we'll be getting
1885                  * EADDRINUSE because no SOCK_STREAM sockets in the system
1886                  * can share both local and remote addresses, localIP:20
1887                  * and *:* in this case.
1888                  */
1889                 if (bind(s, (struct sockaddr *)&data_source,
1890                     data_source.su_len) >= 0)
1891                         break;
1892                 if (errno != EADDRINUSE || tries > 10)
1893                         goto bad;
1894                 sleep(tries);
1895         }
1896         (void) seteuid(pw->pw_uid);
1897 #ifdef IP_TOS
1898         if (data_source.su_family == AF_INET)
1899       {
1900         on = IPTOS_THROUGHPUT;
1901         if (setsockopt(s, IPPROTO_IP, IP_TOS, &on, sizeof(int)) < 0)
1902                 syslog(LOG_WARNING, "data setsockopt (IP_TOS): %m");
1903       }
1904 #endif
1905 #ifdef TCP_NOPUSH
1906         /*
1907          * Turn off push flag to keep sender TCP from sending short packets
1908          * at the boundaries of each write().
1909          */
1910         on = 1;
1911         if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, &on, sizeof on) < 0)
1912                 syslog(LOG_WARNING, "data setsockopt (TCP_NOPUSH): %m");
1913 #endif
1914         return (fdopen(s, mode));
1915 bad:
1916         /* Return the real value of errno (close may change it) */
1917         t = errno;
1918         (void) seteuid(pw->pw_uid);
1919         (void) close(s);
1920         errno = t;
1921         return (NULL);
1922 }
1923
1924 static FILE *
1925 dataconn(char *name, off_t size, char *mode)
1926 {
1927         char sizebuf[32];
1928         FILE *file;
1929         int retry = 0, tos, conerrno;
1930
1931         file_size = size;
1932         byte_count = 0;
1933         if (size != -1)
1934                 (void) snprintf(sizebuf, sizeof(sizebuf),
1935                                 " (%jd bytes)", (intmax_t)size);
1936         else
1937                 *sizebuf = '\0';
1938         if (pdata >= 0) {
1939                 union sockunion from;
1940                 socklen_t fromlen = ctrl_addr.su_len;
1941                 int flags, s;
1942                 struct timeval timeout;
1943                 fd_set set;
1944
1945                 FD_ZERO(&set);
1946                 FD_SET(pdata, &set);
1947
1948                 timeout.tv_usec = 0;
1949                 timeout.tv_sec = 120;
1950
1951                 /*
1952                  * Granted a socket is in the blocking I/O mode,
1953                  * accept() will block after a successful select()
1954                  * if the selected connection dies in between.
1955                  * Therefore set the non-blocking I/O flag here.
1956                  */
1957                 if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1958                     fcntl(pdata, F_SETFL, flags | O_NONBLOCK) == -1)
1959                         goto pdata_err;
1960                 if (select(pdata+1, &set, NULL, NULL, &timeout) <= 0 ||
1961                     (s = accept(pdata, (struct sockaddr *) &from, &fromlen)) < 0)
1962                         goto pdata_err;
1963                 (void) close(pdata);
1964                 pdata = s;
1965                 /*
1966                  * Unset the inherited non-blocking I/O flag
1967                  * on the child socket so stdio can work on it.
1968                  */
1969                 if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1970                     fcntl(pdata, F_SETFL, flags & ~O_NONBLOCK) == -1)
1971                         goto pdata_err;
1972 #ifdef IP_TOS
1973                 if (from.su_family == AF_INET)
1974               {
1975                 tos = IPTOS_THROUGHPUT;
1976                 if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
1977                         syslog(LOG_WARNING, "pdata setsockopt (IP_TOS): %m");
1978               }
1979 #endif
1980                 reply(150, "Opening %s mode data connection for '%s'%s.",
1981                      type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
1982                 return (fdopen(pdata, mode));
1983 pdata_err:
1984                 reply(425, "Can't open data connection.");
1985                 (void) close(pdata);
1986                 pdata = -1;
1987                 return (NULL);
1988         }
1989         if (data >= 0) {
1990                 reply(125, "Using existing data connection for '%s'%s.",
1991                     name, sizebuf);
1992                 usedefault = 1;
1993                 return (fdopen(data, mode));
1994         }
1995         if (usedefault)
1996                 data_dest = his_addr;
1997         usedefault = 1;
1998         do {
1999                 file = getdatasock(mode);
2000                 if (file == NULL) {
2001                         char hostbuf[NI_MAXHOST], portbuf[NI_MAXSERV];
2002
2003                         if (getnameinfo((struct sockaddr *)&data_source,
2004                                 data_source.su_len,
2005                                 hostbuf, sizeof(hostbuf) - 1,
2006                                 portbuf, sizeof(portbuf) - 1,
2007                                 NI_NUMERICHOST|NI_NUMERICSERV))
2008                                         *hostbuf = *portbuf = 0;
2009                         hostbuf[sizeof(hostbuf) - 1] = 0;
2010                         portbuf[sizeof(portbuf) - 1] = 0;
2011                         reply(425, "Can't create data socket (%s,%s): %s.",
2012                                 hostbuf, portbuf, strerror(errno));
2013                         return (NULL);
2014                 }
2015                 data = fileno(file);
2016                 conerrno = 0;
2017                 if (connect(data, (struct sockaddr *)&data_dest,
2018                     data_dest.su_len) == 0)
2019                         break;
2020                 conerrno = errno;
2021                 (void) fclose(file);
2022                 data = -1;
2023                 if (conerrno == EADDRINUSE) {
2024                         sleep(swaitint);
2025                         retry += swaitint;
2026                 } else {
2027                         break;
2028                 }
2029         } while (retry <= swaitmax);
2030         if (conerrno != 0) {
2031                 reply(425, "Can't build data connection: %s.",
2032                            strerror(conerrno));
2033                 return (NULL);
2034         }
2035         reply(150, "Opening %s mode data connection for '%s'%s.",
2036              type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
2037         return (file);
2038 }
2039
2040 /*
2041  * A helper macro to avoid code duplication
2042  * in send_data() and receive_data().
2043  *
2044  * XXX We have to block SIGURG during putc() because BSD stdio
2045  * is unable to restart interrupted write operations and hence
2046  * the entire buffer contents will be lost as soon as a write()
2047  * call indicates EINTR to stdio.
2048  */
2049 #define FTPD_PUTC(ch, file, label)                                      \
2050         do {                                                            \
2051                 int ret;                                                \
2052                                                                         \
2053                 do {                                                    \
2054                         START_UNSAFE;                                   \
2055                         ret = putc((ch), (file));                       \
2056                         END_UNSAFE;                                     \
2057                         CHECKOOB(return (-1))                           \
2058                         else if (ferror(file))                          \
2059                                 goto label;                             \
2060                         clearerr(file);                                 \
2061                 } while (ret == EOF);                                   \
2062         } while (0)
2063
2064 /*
2065  * Transfer the contents of "instr" to "outstr" peer using the appropriate
2066  * encapsulation of the data subject to Mode, Structure, and Type.
2067  *
2068  * NB: Form isn't handled.
2069  */
2070 static int
2071 send_data(FILE *instr, FILE *outstr, size_t blksize, off_t filesize, int isreg)
2072 {
2073         int c, cp, filefd, netfd;
2074         char *buf;
2075
2076         STARTXFER;
2077
2078         switch (type) {
2079
2080         case TYPE_A:
2081                 cp = EOF;
2082                 for (;;) {
2083                         c = getc(instr);
2084                         CHECKOOB(return (-1))
2085                         else if (c == EOF && ferror(instr))
2086                                 goto file_err;
2087                         if (c == EOF) {
2088                                 if (ferror(instr)) {    /* resume after OOB */
2089                                         clearerr(instr);
2090                                         continue;
2091                                 }
2092                                 if (feof(instr))        /* EOF */
2093                                         break;
2094                                 syslog(LOG_ERR, "Internal: impossible condition"
2095                                                 " on file after getc()");
2096                                 goto file_err;
2097                         }
2098                         if (c == '\n' && cp != '\r') {
2099                                 FTPD_PUTC('\r', outstr, data_err);
2100                                 byte_count++;
2101                         }
2102                         FTPD_PUTC(c, outstr, data_err);
2103                         byte_count++;
2104                         cp = c;
2105                 }
2106 #ifdef notyet   /* BSD stdio isn't ready for that */
2107                 while (fflush(outstr) == EOF) {
2108                         CHECKOOB(return (-1))
2109                         else
2110                                 goto data_err;
2111                         clearerr(outstr);
2112                 }
2113                 ENDXFER;
2114 #else
2115                 ENDXFER;
2116                 if (fflush(outstr) == EOF)
2117                         goto data_err;
2118 #endif
2119                 reply(226, "Transfer complete.");
2120                 return (0);
2121
2122         case TYPE_I:
2123         case TYPE_L:
2124                 /*
2125                  * isreg is only set if we are not doing restart and we
2126                  * are sending a regular file
2127                  */
2128                 netfd = fileno(outstr);
2129                 filefd = fileno(instr);
2130
2131                 if (isreg) {
2132                         char *msg = "Transfer complete.";
2133                         off_t cnt, offset;
2134                         int err;
2135
2136                         cnt = offset = 0;
2137
2138                         while (filesize > 0) {
2139                                 err = sendfile(filefd, netfd, offset, 0,
2140                                                NULL, &cnt, 0);
2141                                 /*
2142                                  * Calculate byte_count before OOB processing.
2143                                  * It can be used in myoob() later.
2144                                  */
2145                                 byte_count += cnt;
2146                                 offset += cnt;
2147                                 filesize -= cnt;
2148                                 CHECKOOB(return (-1))
2149                                 else if (err == -1) {
2150                                         if (errno != EINTR &&
2151                                             cnt == 0 && offset == 0)
2152                                                 goto oldway;
2153                                         goto data_err;
2154                                 }
2155                                 if (err == -1)  /* resume after OOB */
2156                                         continue;
2157                                 /*
2158                                  * We hit the EOF prematurely.
2159                                  * Perhaps the file was externally truncated.
2160                                  */
2161                                 if (cnt == 0) {
2162                                         msg = "Transfer finished due to "
2163                                               "premature end of file.";
2164                                         break;
2165                                 }
2166                         }
2167                         ENDXFER;
2168                         reply(226, "%s", msg);
2169                         return (0);
2170                 }
2171
2172 oldway:
2173                 if ((buf = malloc(blksize)) == NULL) {
2174                         ENDXFER;
2175                         reply(451, "Ran out of memory.");
2176                         return (-1);
2177                 }
2178
2179                 for (;;) {
2180                         int cnt, len;
2181                         char *bp;
2182
2183                         cnt = read(filefd, buf, blksize);
2184                         CHECKOOB(free(buf); return (-1))
2185                         else if (cnt < 0) {
2186                                 free(buf);
2187                                 goto file_err;
2188                         }
2189                         if (cnt < 0)    /* resume after OOB */
2190                                 continue;
2191                         if (cnt == 0)   /* EOF */
2192                                 break;
2193                         for (len = cnt, bp = buf; len > 0;) {
2194                                 cnt = write(netfd, bp, len);
2195                                 CHECKOOB(free(buf); return (-1))
2196                                 else if (cnt < 0) {
2197                                         free(buf);
2198                                         goto data_err;
2199                                 }
2200                                 if (cnt <= 0)
2201                                         continue;
2202                                 len -= cnt;
2203                                 bp += cnt;
2204                                 byte_count += cnt;
2205                         }
2206                 }
2207                 ENDXFER;
2208                 free(buf);
2209                 reply(226, "Transfer complete.");
2210                 return (0);
2211         default:
2212                 ENDXFER;
2213                 reply(550, "Unimplemented TYPE %d in send_data.", type);
2214                 return (-1);
2215         }
2216
2217 data_err:
2218         ENDXFER;
2219         perror_reply(426, "Data connection");
2220         return (-1);
2221
2222 file_err:
2223         ENDXFER;
2224         perror_reply(551, "Error on input file");
2225         return (-1);
2226 }
2227
2228 /*
2229  * Transfer data from peer to "outstr" using the appropriate encapulation of
2230  * the data subject to Mode, Structure, and Type.
2231  *
2232  * N.B.: Form isn't handled.
2233  */
2234 static int
2235 receive_data(FILE *instr, FILE *outstr)
2236 {
2237         int c, cp;
2238         int bare_lfs = 0;
2239
2240         STARTXFER;
2241
2242         switch (type) {
2243
2244         case TYPE_I:
2245         case TYPE_L:
2246                 for (;;) {
2247                         int cnt, len;
2248                         char *bp;
2249                         char buf[BUFSIZ];
2250
2251                         cnt = read(fileno(instr), buf, sizeof(buf));
2252                         CHECKOOB(return (-1))
2253                         else if (cnt < 0)
2254                                 goto data_err;
2255                         if (cnt < 0)    /* resume after OOB */
2256                                 continue;
2257                         if (cnt == 0)   /* EOF */
2258                                 break;
2259                         for (len = cnt, bp = buf; len > 0;) {
2260                                 cnt = write(fileno(outstr), bp, len);
2261                                 CHECKOOB(return (-1))
2262                                 else if (cnt < 0)
2263                                         goto file_err;
2264                                 if (cnt <= 0)
2265                                         continue;
2266                                 len -= cnt;
2267                                 bp += cnt;
2268                                 byte_count += cnt;
2269                         }
2270                 }
2271                 ENDXFER;
2272                 return (0);
2273
2274         case TYPE_E:
2275                 ENDXFER;
2276                 reply(553, "TYPE E not implemented.");
2277                 return (-1);
2278
2279         case TYPE_A:
2280                 cp = EOF;
2281                 for (;;) {
2282                         c = getc(instr);
2283                         CHECKOOB(return (-1))
2284                         else if (c == EOF && ferror(instr))
2285                                 goto data_err;
2286                         if (c == EOF && ferror(instr)) { /* resume after OOB */
2287                                 clearerr(instr);
2288                                 continue;
2289                         }
2290
2291                         if (cp == '\r') {
2292                                 if (c != '\n')
2293                                         FTPD_PUTC('\r', outstr, file_err);
2294                         } else
2295                                 if (c == '\n')
2296                                         bare_lfs++;
2297                         if (c == '\r') {
2298                                 byte_count++;
2299                                 cp = c;
2300                                 continue;
2301                         }
2302
2303                         /* Check for EOF here in order not to lose last \r. */
2304                         if (c == EOF) {
2305                                 if (feof(instr))        /* EOF */
2306                                         break;
2307                                 syslog(LOG_ERR, "Internal: impossible condition"
2308                                                 " on data stream after getc()");
2309                                 goto data_err;
2310                         }
2311
2312                         byte_count++;
2313                         FTPD_PUTC(c, outstr, file_err);
2314                         cp = c;
2315                 }
2316 #ifdef notyet   /* BSD stdio isn't ready for that */
2317                 while (fflush(outstr) == EOF) {
2318                         CHECKOOB(return (-1))
2319                         else
2320                                 goto file_err;
2321                         clearerr(outstr);
2322                 }
2323                 ENDXFER;
2324 #else
2325                 ENDXFER;
2326                 if (fflush(outstr) == EOF)
2327                         goto file_err;
2328 #endif
2329                 if (bare_lfs) {
2330                         lreply(226,
2331                 "WARNING! %d bare linefeeds received in ASCII mode.",
2332                             bare_lfs);
2333                 (void)printf("   File may not have transferred correctly.\r\n");
2334                 }
2335                 return (0);
2336         default:
2337                 ENDXFER;
2338                 reply(550, "Unimplemented TYPE %d in receive_data.", type);
2339                 return (-1);
2340         }
2341
2342 data_err:
2343         ENDXFER;
2344         perror_reply(426, "Data connection");
2345         return (-1);
2346
2347 file_err:
2348         ENDXFER;
2349         perror_reply(452, "Error writing to file");
2350         return (-1);
2351 }
2352
2353 void
2354 statfilecmd(char *filename)
2355 {
2356         FILE *fin;
2357         int atstart;
2358         int c, code;
2359         char line[LINE_MAX];
2360         struct stat st;
2361
2362         code = lstat(filename, &st) == 0 && S_ISDIR(st.st_mode) ? 212 : 213;
2363         (void)snprintf(line, sizeof(line), _PATH_LS " -lgA %s", filename);
2364         fin = ftpd_popen(line, "r");
2365         if (fin == NULL) {
2366                 perror_reply(551, filename);
2367                 return;
2368         }
2369         lreply(code, "Status of %s:", filename);
2370         atstart = 1;
2371         while ((c = getc(fin)) != EOF) {
2372                 if (c == '\n') {
2373                         if (ferror(stdout)){
2374                                 perror_reply(421, "Control connection");
2375                                 (void) ftpd_pclose(fin);
2376                                 dologout(1);
2377                                 /* NOTREACHED */
2378                         }
2379                         if (ferror(fin)) {
2380                                 perror_reply(551, filename);
2381                                 (void) ftpd_pclose(fin);
2382                                 return;
2383                         }
2384                         (void) putc('\r', stdout);
2385                 }
2386                 /*
2387                  * RFC 959 says neutral text should be prepended before
2388                  * a leading 3-digit number followed by whitespace, but
2389                  * many ftp clients can be confused by any leading digits,
2390                  * as a matter of fact.
2391                  */
2392                 if (atstart && isdigit(c))
2393                         (void) putc(' ', stdout);
2394                 (void) putc(c, stdout);
2395                 atstart = (c == '\n');
2396         }
2397         (void) ftpd_pclose(fin);
2398         reply(code, "End of status.");
2399 }
2400
2401 void
2402 statcmd(void)
2403 {
2404         union sockunion *su;
2405         u_char *a, *p;
2406         char hname[NI_MAXHOST];
2407         int ispassive;
2408
2409         if (hostinfo) {
2410                 lreply(211, "%s FTP server status:", hostname);
2411                 printf("     %s\r\n", version);
2412         } else
2413                 lreply(211, "FTP server status:");
2414         printf("     Connected to %s", remotehost);
2415         if (!getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
2416                          hname, sizeof(hname) - 1, NULL, 0, NI_NUMERICHOST)) {
2417                 hname[sizeof(hname) - 1] = 0;
2418                 if (strcmp(hname, remotehost) != 0)
2419                         printf(" (%s)", hname);
2420         }
2421         printf("\r\n");
2422         if (logged_in) {
2423                 if (guest)
2424                         printf("     Logged in anonymously\r\n");
2425                 else
2426                         printf("     Logged in as %s\r\n", pw->pw_name);
2427         } else if (askpasswd)
2428                 printf("     Waiting for password\r\n");
2429         else
2430                 printf("     Waiting for user name\r\n");
2431         printf("     TYPE: %s", typenames[type]);
2432         if (type == TYPE_A || type == TYPE_E)
2433                 printf(", FORM: %s", formnames[form]);
2434         if (type == TYPE_L)
2435 #if CHAR_BIT == 8
2436                 printf(" %d", CHAR_BIT);
2437 #else
2438                 printf(" %d", bytesize);        /* need definition! */
2439 #endif
2440         printf("; STRUcture: %s; transfer MODE: %s\r\n",
2441             strunames[stru], modenames[mode]);
2442         if (data != -1)
2443                 printf("     Data connection open\r\n");
2444         else if (pdata != -1) {
2445                 ispassive = 1;
2446                 su = &pasv_addr;
2447                 goto printaddr;
2448         } else if (usedefault == 0) {
2449                 ispassive = 0;
2450                 su = &data_dest;
2451 printaddr:
2452 #define UC(b) (((int) b) & 0xff)
2453                 if (epsvall) {
2454                         printf("     EPSV only mode (EPSV ALL)\r\n");
2455                         goto epsvonly;
2456                 }
2457
2458                 /* PORT/PASV */
2459                 if (su->su_family == AF_INET) {
2460                         a = (u_char *) &su->su_sin.sin_addr;
2461                         p = (u_char *) &su->su_sin.sin_port;
2462                         printf("     %s (%d,%d,%d,%d,%d,%d)\r\n",
2463                                 ispassive ? "PASV" : "PORT",
2464                                 UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2465                                 UC(p[0]), UC(p[1]));
2466                 }
2467
2468                 /* LPRT/LPSV */
2469             {
2470                 int alen, af, i;
2471
2472                 switch (su->su_family) {
2473                 case AF_INET:
2474                         a = (u_char *) &su->su_sin.sin_addr;
2475                         p = (u_char *) &su->su_sin.sin_port;
2476                         alen = sizeof(su->su_sin.sin_addr);
2477                         af = 4;
2478                         break;
2479                 case AF_INET6:
2480                         a = (u_char *) &su->su_sin6.sin6_addr;
2481                         p = (u_char *) &su->su_sin6.sin6_port;
2482                         alen = sizeof(su->su_sin6.sin6_addr);
2483                         af = 6;
2484                         break;
2485                 default:
2486                         af = 0;
2487                         break;
2488                 }
2489                 if (af) {
2490                         printf("     %s (%d,%d,", ispassive ? "LPSV" : "LPRT",
2491                                 af, alen);
2492                         for (i = 0; i < alen; i++)
2493                                 printf("%d,", UC(a[i]));
2494                         printf("%d,%d,%d)\r\n", 2, UC(p[0]), UC(p[1]));
2495                 }
2496             }
2497
2498 epsvonly:;
2499                 /* EPRT/EPSV */
2500             {
2501                 int af;
2502
2503                 switch (su->su_family) {
2504                 case AF_INET:
2505                         af = 1;
2506                         break;
2507                 case AF_INET6:
2508                         af = 2;
2509                         break;
2510                 default:
2511                         af = 0;
2512                         break;
2513                 }
2514                 if (af) {
2515                         union sockunion tmp;
2516
2517                         tmp = *su;
2518                         if (tmp.su_family == AF_INET6)
2519                                 tmp.su_sin6.sin6_scope_id = 0;
2520                         if (!getnameinfo((struct sockaddr *)&tmp, tmp.su_len,
2521                                         hname, sizeof(hname) - 1, NULL, 0,
2522                                         NI_NUMERICHOST)) {
2523                                 hname[sizeof(hname) - 1] = 0;
2524                                 printf("     %s |%d|%s|%d|\r\n",
2525                                         ispassive ? "EPSV" : "EPRT",
2526                                         af, hname, htons(tmp.su_port));
2527                         }
2528                 }
2529             }
2530 #undef UC
2531         } else
2532                 printf("     No data connection\r\n");
2533         reply(211, "End of status.");
2534 }
2535
2536 void
2537 fatalerror(char *s)
2538 {
2539
2540         reply(451, "Error in server: %s", s);
2541         reply(221, "Closing connection due to server error.");
2542         dologout(0);
2543         /* NOTREACHED */
2544 }
2545
2546 void
2547 reply(int n, const char *fmt, ...)
2548 {
2549         va_list ap;
2550
2551         (void)printf("%d ", n);
2552         va_start(ap, fmt);
2553         (void)vprintf(fmt, ap);
2554         va_end(ap);
2555         (void)printf("\r\n");
2556         (void)fflush(stdout);
2557         if (ftpdebug) {
2558                 syslog(LOG_DEBUG, "<--- %d ", n);
2559                 va_start(ap, fmt);
2560                 vsyslog(LOG_DEBUG, fmt, ap);
2561                 va_end(ap);
2562         }
2563 }
2564
2565 void
2566 lreply(int n, const char *fmt, ...)
2567 {
2568         va_list ap;
2569
2570         (void)printf("%d- ", n);
2571         va_start(ap, fmt);
2572         (void)vprintf(fmt, ap);
2573         va_end(ap);
2574         (void)printf("\r\n");
2575         (void)fflush(stdout);
2576         if (ftpdebug) {
2577                 syslog(LOG_DEBUG, "<--- %d- ", n);
2578                 va_start(ap, fmt);
2579                 vsyslog(LOG_DEBUG, fmt, ap);
2580                 va_end(ap);
2581         }
2582 }
2583
2584 static void
2585 ack(char *s)
2586 {
2587
2588         reply(250, "%s command successful.", s);
2589 }
2590
2591 void
2592 nack(char *s)
2593 {
2594
2595         reply(502, "%s command not implemented.", s);
2596 }
2597
2598 /* ARGSUSED */
2599 void
2600 yyerror(char *s)
2601 {
2602         char *cp;
2603
2604         if ((cp = strchr(cbuf,'\n')))
2605                 *cp = '\0';
2606         reply(500, "%s: command not understood.", cbuf);
2607 }
2608
2609 void
2610 delete(char *name)
2611 {
2612         struct stat st;
2613
2614         LOGCMD("delete", name);
2615         if (lstat(name, &st) < 0) {
2616                 perror_reply(550, name);
2617                 return;
2618         }
2619         if (S_ISDIR(st.st_mode)) {
2620                 if (rmdir(name) < 0) {
2621                         perror_reply(550, name);
2622                         return;
2623                 }
2624                 goto done;
2625         }
2626         if (guest && noguestmod) {
2627                 reply(550, "Operation not permitted.");
2628                 return;
2629         }
2630         if (unlink(name) < 0) {
2631                 perror_reply(550, name);
2632                 return;
2633         }
2634 done:
2635         ack("DELE");
2636 }
2637
2638 void
2639 cwd(char *path)
2640 {
2641
2642         if (chdir(path) < 0)
2643                 perror_reply(550, path);
2644         else
2645                 ack("CWD");
2646 }
2647
2648 void
2649 makedir(char *name)
2650 {
2651         char *s;
2652
2653         LOGCMD("mkdir", name);
2654         if (guest && noguestmkd)
2655                 reply(550, "Operation not permitted.");
2656         else if (mkdir(name, 0777) < 0)
2657                 perror_reply(550, name);
2658         else {
2659                 if ((s = doublequote(name)) == NULL)
2660                         fatalerror("Ran out of memory.");
2661                 reply(257, "\"%s\" directory created.", s);
2662                 free(s);
2663         }
2664 }
2665
2666 void
2667 removedir(char *name)
2668 {
2669
2670         LOGCMD("rmdir", name);
2671         if (rmdir(name) < 0)
2672                 perror_reply(550, name);
2673         else
2674                 ack("RMD");
2675 }
2676
2677 void
2678 pwd(void)
2679 {
2680         char *s, path[MAXPATHLEN + 1];
2681
2682         if (getcwd(path, sizeof(path)) == NULL)
2683                 perror_reply(550, "Get current directory");
2684         else {
2685                 if ((s = doublequote(path)) == NULL)
2686                         fatalerror("Ran out of memory.");
2687                 reply(257, "\"%s\" is current directory.", s);
2688                 free(s);
2689         }
2690 }
2691
2692 char *
2693 renamefrom(char *name)
2694 {
2695         struct stat st;
2696
2697         if (guest && noguestmod) {
2698                 reply(550, "Operation not permitted.");
2699                 return (NULL);
2700         }
2701         if (lstat(name, &st) < 0) {
2702                 perror_reply(550, name);
2703                 return (NULL);
2704         }
2705         reply(350, "File exists, ready for destination name.");
2706         return (name);
2707 }
2708
2709 void
2710 renamecmd(char *from, char *to)
2711 {
2712         struct stat st;
2713
2714         LOGCMD2("rename", from, to);
2715
2716         if (guest && (stat(to, &st) == 0)) {
2717                 reply(550, "%s: permission denied.", to);
2718                 return;
2719         }
2720
2721         if (rename(from, to) < 0)
2722                 perror_reply(550, "rename");
2723         else
2724                 ack("RNTO");
2725 }
2726
2727 static void
2728 dolog(struct sockaddr *who)
2729 {
2730         char who_name[NI_MAXHOST];
2731
2732         realhostname_sa(remotehost, sizeof(remotehost) - 1, who, who->sa_len);
2733         remotehost[sizeof(remotehost) - 1] = 0;
2734         if (getnameinfo(who, who->sa_len,
2735                 who_name, sizeof(who_name) - 1, NULL, 0, NI_NUMERICHOST))
2736                         *who_name = 0;
2737         who_name[sizeof(who_name) - 1] = 0;
2738
2739 #ifdef SETPROCTITLE
2740 #ifdef VIRTUAL_HOSTING
2741         if (thishost != firsthost)
2742                 snprintf(proctitle, sizeof(proctitle), "%s: connected (to %s)",
2743                          remotehost, hostname);
2744         else
2745 #endif
2746                 snprintf(proctitle, sizeof(proctitle), "%s: connected",
2747                          remotehost);
2748         setproctitle("%s", proctitle);
2749 #endif /* SETPROCTITLE */
2750
2751         if (logging) {
2752 #ifdef VIRTUAL_HOSTING
2753                 if (thishost != firsthost)
2754                         syslog(LOG_INFO, "connection from %s (%s) to %s",
2755                                remotehost, who_name, hostname);
2756                 else
2757 #endif
2758                         syslog(LOG_INFO, "connection from %s (%s)",
2759                                remotehost, who_name);
2760         }
2761 }
2762
2763 /*
2764  * Record logout in wtmp file
2765  * and exit with supplied status.
2766  */
2767 void
2768 dologout(int status)
2769 {
2770
2771         if (logged_in && dowtmp) {
2772                 (void) seteuid(0);
2773                 ftpd_logwtmp(wtmpid, NULL, NULL);
2774         }
2775         /* beware of flushing buffers after a SIGPIPE */
2776         _exit(status);
2777 }
2778
2779 static void
2780 sigurg(int signo)
2781 {
2782
2783         recvurg = 1;
2784 }
2785
2786 static void
2787 maskurg(int flag)
2788 {
2789         int oerrno;
2790         sigset_t sset;
2791
2792         if (!transflag) {
2793                 syslog(LOG_ERR, "Internal: maskurg() while no transfer");
2794                 return;
2795         }
2796         oerrno = errno;
2797         sigemptyset(&sset);
2798         sigaddset(&sset, SIGURG);
2799         sigprocmask(flag ? SIG_BLOCK : SIG_UNBLOCK, &sset, NULL);
2800         errno = oerrno;
2801 }
2802
2803 static void
2804 flagxfer(int flag)
2805 {
2806
2807         if (flag) {
2808                 if (transflag)
2809                         syslog(LOG_ERR, "Internal: flagxfer(1): "
2810                                         "transfer already under way");
2811                 transflag = 1;
2812                 maskurg(0);
2813                 recvurg = 0;
2814         } else {
2815                 if (!transflag)
2816                         syslog(LOG_ERR, "Internal: flagxfer(0): "
2817                                         "no active transfer");
2818                 maskurg(1);
2819                 transflag = 0;
2820         }
2821 }
2822
2823 /*
2824  * Returns 0 if OK to resume or -1 if abort requested.
2825  */
2826 static int
2827 myoob(void)
2828 {
2829         char *cp;
2830         int ret;
2831
2832         if (!transflag) {
2833                 syslog(LOG_ERR, "Internal: myoob() while no transfer");
2834                 return (0);
2835         }
2836         cp = tmpline;
2837         ret = get_line(cp, 7, stdin);
2838         if (ret == -1) {
2839                 reply(221, "You could at least say goodbye.");
2840                 dologout(0);
2841         } else if (ret == -2) {
2842                 /* Ignore truncated command. */
2843                 return (0);
2844         }
2845         upper(cp);
2846         if (strcmp(cp, "ABOR\r\n") == 0) {
2847                 tmpline[0] = '\0';
2848                 reply(426, "Transfer aborted. Data connection closed.");
2849                 reply(226, "Abort successful.");
2850                 return (-1);
2851         }
2852         if (strcmp(cp, "STAT\r\n") == 0) {
2853                 tmpline[0] = '\0';
2854                 if (file_size != -1)
2855                         reply(213, "Status: %jd of %jd bytes transferred.",
2856                                    (intmax_t)byte_count, (intmax_t)file_size);
2857                 else
2858                         reply(213, "Status: %jd bytes transferred.",
2859                                    (intmax_t)byte_count);
2860         }
2861         return (0);
2862 }
2863
2864 /*
2865  * Note: a response of 425 is not mentioned as a possible response to
2866  *      the PASV command in RFC959. However, it has been blessed as
2867  *      a legitimate response by Jon Postel in a telephone conversation
2868  *      with Rick Adams on 25 Jan 89.
2869  */
2870 void
2871 passive(void)
2872 {
2873         socklen_t len;
2874         int on;
2875         char *p, *a;
2876
2877         if (pdata >= 0)         /* close old port if one set */
2878                 close(pdata);
2879
2880         pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2881         if (pdata < 0) {
2882                 perror_reply(425, "Can't open passive connection");
2883                 return;
2884         }
2885         on = 1;
2886         if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2887                 syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2888
2889         (void) seteuid(0);
2890
2891 #ifdef IP_PORTRANGE
2892         if (ctrl_addr.su_family == AF_INET) {
2893             on = restricted_data_ports ? IP_PORTRANGE_HIGH
2894                                        : IP_PORTRANGE_DEFAULT;
2895
2896             if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2897                             &on, sizeof(on)) < 0)
2898                     goto pasv_error;
2899         }
2900 #endif
2901 #ifdef IPV6_PORTRANGE
2902         if (ctrl_addr.su_family == AF_INET6) {
2903             on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2904                                        : IPV6_PORTRANGE_DEFAULT;
2905
2906             if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2907                             &on, sizeof(on)) < 0)
2908                     goto pasv_error;
2909         }
2910 #endif
2911
2912         pasv_addr = ctrl_addr;
2913         pasv_addr.su_port = 0;
2914         if (bind(pdata, (struct sockaddr *)&pasv_addr, pasv_addr.su_len) < 0)
2915                 goto pasv_error;
2916
2917         (void) seteuid(pw->pw_uid);
2918
2919         len = sizeof(pasv_addr);
2920         if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2921                 goto pasv_error;
2922         if (listen(pdata, 1) < 0)
2923                 goto pasv_error;
2924         if (pasv_addr.su_family == AF_INET)
2925                 a = (char *) &pasv_addr.su_sin.sin_addr;
2926         else if (pasv_addr.su_family == AF_INET6 &&
2927                  IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr))
2928                 a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
2929         else
2930                 goto pasv_error;
2931
2932         p = (char *) &pasv_addr.su_port;
2933
2934 #define UC(b) (((int) b) & 0xff)
2935
2936         reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
2937                 UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
2938         return;
2939
2940 pasv_error:
2941         (void) seteuid(pw->pw_uid);
2942         (void) close(pdata);
2943         pdata = -1;
2944         perror_reply(425, "Can't open passive connection");
2945         return;
2946 }
2947
2948 /*
2949  * Long Passive defined in RFC 1639.
2950  *     228 Entering Long Passive Mode
2951  *         (af, hal, h1, h2, h3,..., pal, p1, p2...)
2952  */
2953
2954 void
2955 long_passive(char *cmd, int pf)
2956 {
2957         socklen_t len;
2958         int on;
2959         char *p, *a;
2960
2961         if (pdata >= 0)         /* close old port if one set */
2962                 close(pdata);
2963
2964         if (pf != PF_UNSPEC) {
2965                 if (ctrl_addr.su_family != pf) {
2966                         switch (ctrl_addr.su_family) {
2967                         case AF_INET:
2968                                 pf = 1;
2969                                 break;
2970                         case AF_INET6:
2971                                 pf = 2;
2972                                 break;
2973                         default:
2974                                 pf = 0;
2975                                 break;
2976                         }
2977                         /*
2978                          * XXX
2979                          * only EPRT/EPSV ready clients will understand this
2980                          */
2981                         if (strcmp(cmd, "EPSV") == 0 && pf) {
2982                                 reply(522, "Network protocol mismatch, "
2983                                         "use (%d)", pf);
2984                         } else
2985                                 reply(501, "Network protocol mismatch."); /*XXX*/
2986
2987                         return;
2988                 }
2989         }
2990
2991         pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2992         if (pdata < 0) {
2993                 perror_reply(425, "Can't open passive connection");
2994                 return;
2995         }
2996         on = 1;
2997         if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2998                 syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2999
3000         (void) seteuid(0);
3001
3002         pasv_addr = ctrl_addr;
3003         pasv_addr.su_port = 0;
3004         len = pasv_addr.su_len;
3005
3006 #ifdef IP_PORTRANGE
3007         if (ctrl_addr.su_family == AF_INET) {
3008             on = restricted_data_ports ? IP_PORTRANGE_HIGH
3009                                        : IP_PORTRANGE_DEFAULT;
3010
3011             if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
3012                             &on, sizeof(on)) < 0)
3013                     goto pasv_error;
3014         }
3015 #endif
3016 #ifdef IPV6_PORTRANGE
3017         if (ctrl_addr.su_family == AF_INET6) {
3018             on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
3019                                        : IPV6_PORTRANGE_DEFAULT;
3020
3021             if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
3022                             &on, sizeof(on)) < 0)
3023                     goto pasv_error;
3024         }
3025 #endif
3026
3027         if (bind(pdata, (struct sockaddr *)&pasv_addr, len) < 0)
3028                 goto pasv_error;
3029
3030         (void) seteuid(pw->pw_uid);
3031
3032         if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
3033                 goto pasv_error;
3034         if (listen(pdata, 1) < 0)
3035                 goto pasv_error;
3036
3037 #define UC(b) (((int) b) & 0xff)
3038
3039         if (strcmp(cmd, "LPSV") == 0) {
3040                 p = (char *)&pasv_addr.su_port;
3041                 switch (pasv_addr.su_family) {
3042                 case AF_INET:
3043                         a = (char *) &pasv_addr.su_sin.sin_addr;
3044                 v4_reply:
3045                         reply(228,
3046 "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3047                               4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3048                               2, UC(p[0]), UC(p[1]));
3049                         return;
3050                 case AF_INET6:
3051                         if (IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr)) {
3052                                 a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
3053                                 goto v4_reply;
3054                         }
3055                         a = (char *) &pasv_addr.su_sin6.sin6_addr;
3056                         reply(228,
3057 "Entering Long Passive Mode "
3058 "(%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3059                               6, 16, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3060                               UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
3061                               UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
3062                               UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
3063                               2, UC(p[0]), UC(p[1]));
3064                         return;
3065                 }
3066         } else if (strcmp(cmd, "EPSV") == 0) {
3067                 switch (pasv_addr.su_family) {
3068                 case AF_INET:
3069                 case AF_INET6:
3070                         reply(229, "Entering Extended Passive Mode (|||%d|)",
3071                                 ntohs(pasv_addr.su_port));
3072                         return;
3073                 }
3074         } else {
3075                 /* more proper error code? */
3076         }
3077
3078 pasv_error:
3079         (void) seteuid(pw->pw_uid);
3080         (void) close(pdata);
3081         pdata = -1;
3082         perror_reply(425, "Can't open passive connection");
3083         return;
3084 }
3085
3086 /*
3087  * Generate unique name for file with basename "local"
3088  * and open the file in order to avoid possible races.
3089  * Try "local" first, then "local.1", "local.2" etc, up to "local.99".
3090  * Return descriptor to the file, set "name" to its name.
3091  *
3092  * Generates failure reply on error.
3093  */
3094 static int
3095 guniquefd(char *local, char **name)
3096 {
3097         static char new[MAXPATHLEN];
3098         struct stat st;
3099         char *cp;
3100         int count;
3101         int fd;
3102
3103         cp = strrchr(local, '/');
3104         if (cp)
3105                 *cp = '\0';
3106         if (stat(cp ? local : ".", &st) < 0) {
3107                 perror_reply(553, cp ? local : ".");
3108                 return (-1);
3109         }
3110         if (cp) {
3111                 /*
3112                  * Let not overwrite dirname with counter suffix.
3113                  * -4 is for /nn\0
3114                  * In this extreme case dot won't be put in front of suffix.
3115                  */
3116                 if (strlen(local) > sizeof(new) - 4) {
3117                         reply(553, "Pathname too long.");
3118                         return (-1);
3119                 }
3120                 *cp = '/';
3121         }
3122         /* -4 is for the .nn<null> we put on the end below */
3123         (void) snprintf(new, sizeof(new) - 4, "%s", local);
3124         cp = new + strlen(new);
3125         /*
3126          * Don't generate dotfile unless requested explicitly.
3127          * This covers the case when basename gets truncated off
3128          * by buffer size.
3129          */
3130         if (cp > new && cp[-1] != '/')
3131                 *cp++ = '.';
3132         for (count = 0; count < 100; count++) {
3133                 /* At count 0 try unmodified name */
3134                 if (count)
3135                         (void)sprintf(cp, "%d", count);
3136                 if ((fd = open(count ? new : local,
3137                     O_RDWR | O_CREAT | O_EXCL, 0666)) >= 0) {
3138                         *name = count ? new : local;
3139                         return (fd);
3140                 }
3141                 if (errno != EEXIST) {
3142                         perror_reply(553, count ? new : local);
3143                         return (-1);
3144                 }
3145         }
3146         reply(452, "Unique file name cannot be created.");
3147         return (-1);
3148 }
3149
3150 /*
3151  * Format and send reply containing system error number.
3152  */
3153 void
3154 perror_reply(int code, char *string)
3155 {
3156
3157         reply(code, "%s: %s.", string, strerror(errno));
3158 }
3159
3160 static char *onefile[] = {
3161         "",
3162         0
3163 };
3164
3165 void
3166 send_file_list(char *whichf)
3167 {
3168         struct stat st;
3169         DIR *dirp = NULL;
3170         struct dirent *dir;
3171         FILE *dout = NULL;
3172         char **dirlist, *dirname;
3173         int simple = 0;
3174         int freeglob = 0;
3175         glob_t gl;
3176
3177         if (strpbrk(whichf, "~{[*?") != NULL) {
3178                 int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
3179
3180                 memset(&gl, 0, sizeof(gl));
3181                 gl.gl_matchc = MAXGLOBARGS;
3182                 flags |= GLOB_LIMIT;
3183                 freeglob = 1;
3184                 if (glob(whichf, flags, 0, &gl)) {
3185                         reply(550, "No matching files found.");
3186                         goto out;
3187                 } else if (gl.gl_pathc == 0) {
3188                         errno = ENOENT;
3189                         perror_reply(550, whichf);
3190                         goto out;
3191                 }
3192                 dirlist = gl.gl_pathv;
3193         } else {
3194                 onefile[0] = whichf;
3195                 dirlist = onefile;
3196                 simple = 1;
3197         }
3198
3199         while ((dirname = *dirlist++)) {
3200                 if (stat(dirname, &st) < 0) {
3201                         /*
3202                          * If user typed "ls -l", etc, and the client
3203                          * used NLST, do what the user meant.
3204                          */
3205                         if (dirname[0] == '-' && *dirlist == NULL &&
3206                             dout == NULL)
3207                                 retrieve(_PATH_LS " %s", dirname);
3208                         else
3209                                 perror_reply(550, whichf);
3210                         goto out;
3211                 }
3212
3213                 if (S_ISREG(st.st_mode)) {
3214                         if (dout == NULL) {
3215                                 dout = dataconn("file list", -1, "w");
3216                                 if (dout == NULL)
3217                                         goto out;
3218                                 STARTXFER;
3219                         }
3220                         START_UNSAFE;
3221                         fprintf(dout, "%s%s\n", dirname,
3222                                 type == TYPE_A ? "\r" : "");
3223                         END_UNSAFE;
3224                         if (ferror(dout))
3225                                 goto data_err;
3226                         byte_count += strlen(dirname) +
3227                                       (type == TYPE_A ? 2 : 1);
3228                         CHECKOOB(goto abrt);
3229                         continue;
3230                 } else if (!S_ISDIR(st.st_mode))
3231                         continue;
3232
3233                 if ((dirp = opendir(dirname)) == NULL)
3234                         continue;
3235
3236                 while ((dir = readdir(dirp)) != NULL) {
3237                         char nbuf[MAXPATHLEN];
3238
3239                         CHECKOOB(goto abrt);
3240
3241                         if (dir->d_name[0] == '.' && dir->d_namlen == 1)
3242                                 continue;
3243                         if (dir->d_name[0] == '.' && dir->d_name[1] == '.' &&
3244                             dir->d_namlen == 2)
3245                                 continue;
3246
3247                         snprintf(nbuf, sizeof(nbuf),
3248                                 "%s/%s", dirname, dir->d_name);
3249
3250                         /*
3251                          * We have to do a stat to insure it's
3252                          * not a directory or special file.
3253                          */
3254                         if (simple || (stat(nbuf, &st) == 0 &&
3255                             S_ISREG(st.st_mode))) {
3256                                 if (dout == NULL) {
3257                                         dout = dataconn("file list", -1, "w");
3258                                         if (dout == NULL)
3259                                                 goto out;
3260                                         STARTXFER;
3261                                 }
3262                                 START_UNSAFE;
3263                                 if (nbuf[0] == '.' && nbuf[1] == '/')
3264                                         fprintf(dout, "%s%s\n", &nbuf[2],
3265                                                 type == TYPE_A ? "\r" : "");
3266                                 else
3267                                         fprintf(dout, "%s%s\n", nbuf,
3268                                                 type == TYPE_A ? "\r" : "");
3269                                 END_UNSAFE;
3270                                 if (ferror(dout))
3271                                         goto data_err;
3272                                 byte_count += strlen(nbuf) +
3273                                               (type == TYPE_A ? 2 : 1);
3274                                 CHECKOOB(goto abrt);
3275                         }
3276                 }
3277                 (void) closedir(dirp);
3278                 dirp = NULL;
3279         }
3280
3281         if (dout == NULL)
3282                 reply(550, "No files found.");
3283         else if (ferror(dout))
3284 data_err:       perror_reply(550, "Data connection");
3285         else
3286                 reply(226, "Transfer complete.");
3287 out:
3288         if (dout) {
3289                 ENDXFER;
3290 abrt:
3291                 (void) fclose(dout);
3292                 data = -1;
3293                 pdata = -1;
3294         }
3295         if (dirp)
3296                 (void) closedir(dirp);
3297         if (freeglob) {
3298                 freeglob = 0;
3299                 globfree(&gl);
3300         }
3301 }
3302
3303 void
3304 reapchild(int signo)
3305 {
3306         while (waitpid(-1, NULL, WNOHANG) > 0);
3307 }
3308
3309 #ifdef OLD_SETPROCTITLE
3310 /*
3311  * Clobber argv so ps will show what we're doing.  (Stolen from sendmail.)
3312  * Warning, since this is usually started from inetd.conf, it often doesn't
3313  * have much of an environment or arglist to overwrite.
3314  */
3315 void
3316 setproctitle(const char *fmt, ...)
3317 {
3318         int i;
3319         va_list ap;
3320         char *p, *bp, ch;
3321         char buf[LINE_MAX];
3322
3323         va_start(ap, fmt);
3324         (void)vsnprintf(buf, sizeof(buf), fmt, ap);
3325
3326         /* make ps print our process name */
3327         p = Argv[0];
3328         *p++ = '-';
3329
3330         i = strlen(buf);
3331         if (i > LastArgv - p - 2) {
3332                 i = LastArgv - p - 2;
3333                 buf[i] = '\0';
3334         }
3335         bp = buf;
3336         while (ch = *bp++)
3337                 if (ch != '\n' && ch != '\r')
3338                         *p++ = ch;
3339         while (p < LastArgv)
3340                 *p++ = ' ';
3341 }
3342 #endif /* OLD_SETPROCTITLE */
3343
3344 static void
3345 appendf(char **strp, char *fmt, ...)
3346 {
3347         va_list ap;
3348         char *ostr, *p;
3349
3350         va_start(ap, fmt);
3351         vasprintf(&p, fmt, ap);
3352         va_end(ap);
3353         if (p == NULL)
3354                 fatalerror("Ran out of memory.");
3355         if (*strp == NULL)
3356                 *strp = p;
3357         else {
3358                 ostr = *strp;
3359                 asprintf(strp, "%s%s", ostr, p);
3360                 if (*strp == NULL)
3361                         fatalerror("Ran out of memory.");
3362                 free(ostr);
3363         }
3364 }
3365
3366 static void
3367 logcmd(char *cmd, char *file1, char *file2, off_t cnt)
3368 {
3369         char *msg = NULL;
3370         char wd[MAXPATHLEN + 1];
3371
3372         if (logging <= 1)
3373                 return;
3374
3375         if (getcwd(wd, sizeof(wd) - 1) == NULL)
3376                 strcpy(wd, strerror(errno));
3377
3378         appendf(&msg, "%s", cmd);
3379         if (file1)
3380                 appendf(&msg, " %s", file1);
3381         if (file2)
3382                 appendf(&msg, " %s", file2);
3383         if (cnt >= 0)
3384                 appendf(&msg, " = %jd bytes", (intmax_t)cnt);
3385         appendf(&msg, " (wd: %s", wd);
3386         if (guest || dochroot)
3387                 appendf(&msg, "; chrooted");
3388         appendf(&msg, ")");
3389         syslog(LOG_INFO, "%s", msg);
3390         free(msg);
3391 }
3392
3393 static void
3394 logxfer(char *name, off_t size, time_t start)
3395 {
3396         char buf[MAXPATHLEN + 1024];
3397         char path[MAXPATHLEN + 1];
3398         time_t now;
3399
3400         if (statfd >= 0) {
3401                 time(&now);
3402                 if (realpath(name, path) == NULL) {
3403                         syslog(LOG_NOTICE, "realpath failed on %s: %m", path);
3404                         return;
3405                 }
3406                 snprintf(buf, sizeof(buf), "%.20s!%s!%s!%s!%jd!%ld\n",
3407                         ctime(&now)+4, ident, remotehost,
3408                         path, (intmax_t)size,
3409                         (long)(now - start + (now == start)));
3410                 write(statfd, buf, strlen(buf));
3411         }
3412 }
3413
3414 static char *
3415 doublequote(char *s)
3416 {
3417         int n;
3418         char *p, *s2;
3419
3420         for (p = s, n = 0; *p; p++)
3421                 if (*p == '"')
3422                         n++;
3423
3424         if ((s2 = malloc(p - s + n + 1)) == NULL)
3425                 return (NULL);
3426
3427         for (p = s2; *s; s++, p++) {
3428                 if ((*p = *s) == '"')
3429                         *(++p) = '"';
3430         }
3431         *p = '\0';
3432
3433         return (s2);
3434 }
3435
3436 /* setup server socket for specified address family */
3437 /* if af is PF_UNSPEC more than one socket may be returned */
3438 /* the returned list is dynamically allocated, so caller needs to free it */
3439 static int *
3440 socksetup(int af, char *bindname, const char *bindport)
3441 {
3442         struct addrinfo hints, *res, *r;
3443         int error, maxs, *s, *socks;
3444         const int on = 1;
3445
3446         memset(&hints, 0, sizeof(hints));
3447         hints.ai_flags = AI_PASSIVE;
3448         hints.ai_family = af;
3449         hints.ai_socktype = SOCK_STREAM;
3450         error = getaddrinfo(bindname, bindport, &hints, &res);
3451         if (error) {
3452                 syslog(LOG_ERR, "%s", gai_strerror(error));
3453                 if (error == EAI_SYSTEM)
3454                         syslog(LOG_ERR, "%s", strerror(errno));
3455                 return NULL;
3456         }
3457
3458         /* Count max number of sockets we may open */
3459         for (maxs = 0, r = res; r; r = r->ai_next, maxs++)
3460                 ;
3461         socks = malloc((maxs + 1) * sizeof(int));
3462         if (!socks) {
3463                 freeaddrinfo(res);
3464                 syslog(LOG_ERR, "couldn't allocate memory for sockets");
3465                 return NULL;
3466         }
3467
3468         *socks = 0;   /* num of sockets counter at start of array */
3469         s = socks + 1;
3470         for (r = res; r; r = r->ai_next) {
3471                 *s = socket(r->ai_family, r->ai_socktype, r->ai_protocol);
3472                 if (*s < 0) {
3473                         syslog(LOG_DEBUG, "control socket: %m");
3474                         continue;
3475                 }
3476                 if (setsockopt(*s, SOL_SOCKET, SO_REUSEADDR,
3477                     &on, sizeof(on)) < 0)
3478                         syslog(LOG_WARNING,
3479                             "control setsockopt (SO_REUSEADDR): %m");
3480                 if (r->ai_family == AF_INET6) {
3481                         if (setsockopt(*s, IPPROTO_IPV6, IPV6_V6ONLY,
3482                             &on, sizeof(on)) < 0)
3483                                 syslog(LOG_WARNING,
3484                                     "control setsockopt (IPV6_V6ONLY): %m");
3485                 }
3486                 if (bind(*s, r->ai_addr, r->ai_addrlen) < 0) {
3487                         syslog(LOG_DEBUG, "control bind: %m");
3488                         close(*s);
3489                         continue;
3490                 }
3491                 (*socks)++;
3492                 s++;
3493         }
3494
3495         if (res)
3496                 freeaddrinfo(res);
3497
3498         if (*socks == 0) {
3499                 syslog(LOG_ERR, "control socket: Couldn't bind to any socket");
3500                 free(socks);
3501                 return NULL;
3502         }
3503         return(socks);
3504 }