libexec/ftpd/ftpd.c

   1 /*
   2  * Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #if 0
  35 #ifndef lint
  36 static char copyright[] =
  37 "@(#) Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994\n\
  38         The Regents of the University of California.  All rights reserved.\n";
  39 #endif /* not lint */
  40 #endif
  41
  42 #ifndef lint
  43 #if 0
  44 static char sccsid[] = "@(#)ftpd.c      8.4 (Berkeley) 4/16/94";
  45 #endif
  46 #endif /* not lint */
  47
  48 #include <sys/cdefs.h>
  49 __FBSDID("$FreeBSD$");
  50
  51 /*
  52  * FTP server.
  53  */
  54 #include <sys/param.h>
  55 #include <sys/ioctl.h>
  56 #include <sys/mman.h>
  57 #include <sys/socket.h>
  58 #include <sys/stat.h>
  59 #include <sys/time.h>
  60 #include <sys/wait.h>
  61
  62 #include <netinet/in.h>
  63 #include <netinet/in_systm.h>
  64 #include <netinet/ip.h>
  65 #include <netinet/tcp.h>
  66
  67 #define FTP_NAMES
  68 #include <arpa/ftp.h>
  69 #include <arpa/inet.h>
  70 #include <arpa/telnet.h>
  71
  72 #include <ctype.h>
  73 #include <dirent.h>
  74 #include <err.h>
  75 #include <errno.h>
  76 #include <fcntl.h>
  77 #include <glob.h>
  78 #include <limits.h>
  79 #include <netdb.h>
  80 #include <pwd.h>
  81 #include <grp.h>
  82 #include <opie.h>
  83 #include <signal.h>
  84 #include <stdint.h>
  85 #include <stdio.h>
  86 #include <stdlib.h>
  87 #include <string.h>
  88 #include <syslog.h>
  89 #include <time.h>
  90 #include <unistd.h>
  91 #include <libutil.h>
  92 #ifdef  LOGIN_CAP
  93 #include <login_cap.h>
  94 #endif
  95
  96 #ifdef USE_PAM
  97 #include <security/pam_appl.h>
  98 #endif
  99
 100 #include "pathnames.h"
 101 #include "extern.h"
 102
 103 #include <stdarg.h>
 104
 105 static char version[] = "Version 6.00LS";
 106 #undef main
 107
 108 extern  off_t restart_point;
 109 extern  char cbuf[];
 110
 111 union sockunion ctrl_addr;
 112 union sockunion data_source;
 113 union sockunion data_dest;
 114 union sockunion his_addr;
 115 union sockunion pasv_addr;
 116
 117 int     daemon_mode;
 118 int     data;
 119 int     dataport;
 120 int     hostinfo = 1;   /* print host-specific info in messages */
 121 int     logged_in;
 122 struct  passwd *pw;
 123 char    *homedir;
 124 int     ftpdebug;
 125 int     timeout = 900;    /* timeout after 15 minutes of inactivity */
 126 int     maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */
 127 int     logging;
 128 int     restricted_data_ports = 1;
 129 int     paranoid = 1;     /* be extra careful about security */
 130 int     anon_only = 0;    /* Only anonymous ftp allowed */
 131 int     guest;
 132 int     dochroot;
 133 char    *chrootdir;
 134 int     dowtmp = 1;
 135 int     stats;
 136 int     statfd = -1;
 137 int     type;
 138 int     form;
 139 int     stru;                   /* avoid C keyword */
 140 int     mode;
 141 int     usedefault = 1;         /* for data transfers */
 142 int     pdata = -1;             /* for passive mode */
 143 int     readonly = 0;           /* Server is in readonly mode.  */
 144 int     noepsv = 0;             /* EPSV command is disabled.    */
 145 int     noretr = 0;             /* RETR command is disabled.    */
 146 int     noguestretr = 0;        /* RETR command is disabled for anon users. */
 147 int     noguestmkd = 0;         /* MKD command is disabled for anon users. */
 148 int     noguestmod = 1;         /* anon users may not modify existing files. */
 149
 150 off_t   file_size;
 151 off_t   byte_count;
 152 #if !defined(CMASK) || CMASK == 0
 153 #undef CMASK
 154 #define CMASK 027
 155 #endif
 156 int     defumask = CMASK;               /* default umask value */
 157 char    tmpline[7];
 158 char    *hostname;
 159 int     epsvall = 0;
 160
 161 #ifdef VIRTUAL_HOSTING
 162 char    *ftpuser;
 163
 164 static struct ftphost {
 165         struct ftphost  *next;
 166         struct addrinfo *hostinfo;
 167         char            *hostname;
 168         char            *anonuser;
 169         char            *statfile;
 170         char            *welcome;
 171         char            *loginmsg;
 172 } *thishost, *firsthost;
 173
 174 #endif
 175 char    remotehost[NI_MAXHOST];
 176 char    *ident = NULL;
 177
 178 static char     ttyline[20];
 179 char            *tty = ttyline;         /* for klogin */
 180
 181 #ifdef USE_PAM
 182 static int      auth_pam(struct passwd**, const char*);
 183 pam_handle_t    *pamh = NULL;
 184 #endif
 185
 186 static struct opie      opiedata;
 187 static char             opieprompt[OPIE_CHALLENGE_MAX+1];
 188 static int              pwok;
 189
 190 char    *pid_file = NULL;
 191
 192 /*
 193  * Limit number of pathnames that glob can return.
 194  * A limit of 0 indicates the number of pathnames is unlimited.
 195  */
 196 #define MAXGLOBARGS     16384
 197 #
 198
 199 /*
 200  * Timeout intervals for retrying connections
 201  * to hosts that don't accept PORT cmds.  This
 202  * is a kludge, but given the problems with TCP...
 203  */
 204 #define SWAITMAX        90      /* wait at most 90 seconds */
 205 #define SWAITINT        5       /* interval between retries */
 206
 207 int     swaitmax = SWAITMAX;
 208 int     swaitint = SWAITINT;
 209
 210 #ifdef SETPROCTITLE
 211 #ifdef OLD_SETPROCTITLE
 212 char    **Argv = NULL;          /* pointer to argument vector */
 213 char    *LastArgv = NULL;       /* end of argv */
 214 #endif /* OLD_SETPROCTITLE */
 215 char    proctitle[LINE_MAX];    /* initial part of title */
 216 #endif /* SETPROCTITLE */
 217
 218 #define LOGCMD(cmd, file)               logcmd((cmd), (file), NULL, -1)
 219 #define LOGCMD2(cmd, file1, file2)      logcmd((cmd), (file1), (file2), -1)
 220 #define LOGBYTES(cmd, file, cnt)        logcmd((cmd), (file), NULL, (cnt))
 221
 222 static  volatile sig_atomic_t recvurg;
 223 static  int transflag;          /* NB: for debugging only */
 224
 225 #define STARTXFER       flagxfer(1)
 226 #define ENDXFER         flagxfer(0)
 227
 228 #define START_UNSAFE    maskurg(1)
 229 #define END_UNSAFE      maskurg(0)
 230
 231 /* It's OK to put an `else' clause after this macro. */
 232 #define CHECKOOB(action)                                                \
 233         if (recvurg) {                                                  \
 234                 recvurg = 0;                                            \
 235                 if (myoob()) {                                          \
 236                         ENDXFER;                                        \
 237                         action;                                         \
 238                 }                                                       \
 239         }
 240
 241 #ifdef VIRTUAL_HOSTING
 242 static void      inithosts(void);
 243 static void      selecthost(union sockunion *);
 244 #endif
 245 static void      ack(char *);
 246 static void      sigurg(int);
 247 static void      maskurg(int);
 248 static void      flagxfer(int);
 249 static int       myoob(void);
 250 static int       checkuser(char *, char *, int, char **);
 251 static FILE     *dataconn(char *, off_t, char *);
 252 static void      dolog(struct sockaddr *);
 253 static void      end_login(void);
 254 static FILE     *getdatasock(char *);
 255 static int       guniquefd(char *, char **);
 256 static void      lostconn(int);
 257 static void      sigquit(int);
 258 static int       receive_data(FILE *, FILE *);
 259 static int       send_data(FILE *, FILE *, size_t, off_t, int);
 260 static struct passwd *
 261                  sgetpwnam(char *);
 262 static char     *sgetsave(char *);
 263 static void      reapchild(int);
 264 static void      appendf(char **, char *, ...) __printflike(2, 3);
 265 static void      logcmd(char *, char *, char *, off_t);
 266 static void      logxfer(char *, off_t, time_t);
 267 static char     *doublequote(char *);
 268 static int      *socksetup(int, char *, const char *);
 269
 270 int
 271 main(int argc, char *argv[], char **envp)
 272 {
 273         socklen_t addrlen;
 274         int ch, on = 1, tos;
 275         char *cp, line[LINE_MAX];
 276         FILE *fd;
 277         char    *bindname = NULL;
 278         const char *bindport = "ftp";
 279         int     family = AF_UNSPEC;
 280         struct sigaction sa;
 281
 282         tzset();                /* in case no timezone database in ~ftp */
 283         sigemptyset(&sa.sa_mask);
 284         sa.sa_flags = SA_RESTART;
 285
 286 #ifdef OLD_SETPROCTITLE
 287         /*
 288          *  Save start and extent of argv for setproctitle.
 289          */
 290         Argv = argv;
 291         while (*envp)
 292                 envp++;
 293         LastArgv = envp[-1] + strlen(envp[-1]);
 294 #endif /* OLD_SETPROCTITLE */
 295
 296         /*
 297          * Prevent diagnostic messages from appearing on stderr.
 298          * We run as a daemon or from inetd; in both cases, there's
 299          * more reason in logging to syslog.
 300          */
 301         (void) freopen(_PATH_DEVNULL, "w", stderr);
 302         opterr = 0;
 303
 304         /*
 305          * LOG_NDELAY sets up the logging connection immediately,
 306          * necessary for anonymous ftp's that chroot and can't do it later.
 307          */
 308         openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP);
 309
 310         while ((ch = getopt(argc, argv,
 311                             "46a:AdDEhlmMoOp:P:rRSt:T:u:UvW")) != -1) {
 312                 switch (ch) {
 313                 case '4':
 314                         family = (family == AF_INET6) ? AF_UNSPEC : AF_INET;
 315                         break;
 316
 317                 case '6':
 318                         family = (family == AF_INET) ? AF_UNSPEC : AF_INET6;
 319                         break;
 320
 321                 case 'a':
 322                         bindname = optarg;
 323                         break;
 324
 325                 case 'A':
 326                         anon_only = 1;
 327                         break;
 328
 329                 case 'd':
 330                         ftpdebug++;
 331                         break;
 332
 333                 case 'D':
 334                         daemon_mode++;
 335                         break;
 336
 337                 case 'E':
 338                         noepsv = 1;
 339                         break;
 340
 341                 case 'h':
 342                         hostinfo = 0;
 343                         break;
 344
 345                 case 'l':
 346                         logging++;      /* > 1 == extra logging */
 347                         break;
 348
 349                 case 'm':
 350                         noguestmod = 0;
 351                         break;
 352
 353                 case 'M':
 354                         noguestmkd = 1;
 355                         break;
 356
 357                 case 'o':
 358                         noretr = 1;
 359                         break;
 360
 361                 case 'O':
 362                         noguestretr = 1;
 363                         break;
 364
 365                 case 'p':
 366                         pid_file = optarg;
 367                         break;
 368
 369                 case 'P':
 370                         bindport = optarg;
 371                         break;
 372
 373                 case 'r':
 374                         readonly = 1;
 375                         break;
 376
 377                 case 'R':
 378                         paranoid = 0;
 379                         break;
 380
 381                 case 'S':
 382                         stats++;
 383                         break;
 384
 385                 case 't':
 386                         timeout = atoi(optarg);
 387                         if (maxtimeout < timeout)
 388                                 maxtimeout = timeout;
 389                         break;
 390
 391                 case 'T':
 392                         maxtimeout = atoi(optarg);
 393                         if (timeout > maxtimeout)
 394                                 timeout = maxtimeout;
 395                         break;
 396
 397                 case 'u':
 398                     {
 399                         long val = 0;
 400
 401                         val = strtol(optarg, &optarg, 8);
 402                         if (*optarg != '\0' || val < 0)
 403                                 syslog(LOG_WARNING, "bad value for -u");
 404                         else
 405                                 defumask = val;
 406                         break;
 407                     }
 408                 case 'U':
 409                         restricted_data_ports = 0;
 410                         break;
 411
 412                 case 'v':
 413                         ftpdebug++;
 414                         break;
 415
 416                 case 'W':
 417                         dowtmp = 0;
 418                         break;
 419
 420                 default:
 421                         syslog(LOG_WARNING, "unknown flag -%c ignored", optopt);
 422                         break;
 423                 }
 424         }
 425
 426 #ifdef VIRTUAL_HOSTING
 427         inithosts();
 428 #endif
 429
 430         if (daemon_mode) {
 431                 int *ctl_sock, fd, maxfd = -1, nfds, i;
 432                 fd_set defreadfds, readfds;
 433                 pid_t pid;
 434
 435                 /*
 436                  * Detach from parent.
 437                  */
 438                 if (daemon(1, 1) < 0) {
 439                         syslog(LOG_ERR, "failed to become a daemon");
 440                         exit(1);
 441                 }
 442                 sa.sa_handler = reapchild;
 443                 (void)sigaction(SIGCHLD, &sa, NULL);
 444
 445                 /*
 446                  * Open a socket, bind it to the FTP port, and start
 447                  * listening.
 448                  */
 449                 ctl_sock = socksetup(family, bindname, bindport);
 450                 if (ctl_sock == NULL)
 451                         exit(1);
 452
 453                 FD_ZERO(&defreadfds);
 454                 for (i = 1; i <= *ctl_sock; i++) {
 455                         FD_SET(ctl_sock[i], &defreadfds);
 456                         if (listen(ctl_sock[i], 32) < 0) {
 457                                 syslog(LOG_ERR, "control listen: %m");
 458                                 exit(1);
 459                         }
 460                         if (maxfd < ctl_sock[i])
 461                                 maxfd = ctl_sock[i];
 462                 }
 463
 464                 /*
 465                  * Atomically write process ID
 466                  */
 467                 if (pid_file)
 468                 {
 469                         int fd;
 470                         char buf[20];
 471
 472                         fd = open(pid_file, O_CREAT | O_WRONLY | O_TRUNC
 473                                 | O_NONBLOCK | O_EXLOCK, 0644);
 474                         if (fd < 0) {
 475                                 if (errno == EAGAIN)
 476                                         syslog(LOG_ERR,
 477                                             "%s: already locked", pid_file);
 478                                 else
 479                                         syslog(LOG_ERR, "%s: %m", pid_file);
 480                                 exit(1);
 481                         }
 482                         snprintf(buf, sizeof(buf),
 483                                 "%lu\n", (unsigned long) getpid());
 484                         if (write(fd, buf, strlen(buf)) < 0) {
 485                                 syslog(LOG_ERR, "%s: write: %m", pid_file);
 486                                 exit(1);
 487                         }
 488                         /* Leave the pid file open and locked */
 489                 }
 490                 /*
 491                  * Loop forever accepting connection requests and forking off
 492                  * children to handle them.
 493                  */
 494                 while (1) {
 495                         FD_COPY(&defreadfds, &readfds);
 496                         nfds = select(maxfd + 1, &readfds, NULL, NULL, 0);
 497                         if (nfds <= 0) {
 498                                 if (nfds < 0 && errno != EINTR)
 499                                         syslog(LOG_WARNING, "select: %m");
 500                                 continue;
 501                         }
 502
 503                         pid = -1;
 504                         for (i = 1; i <= *ctl_sock; i++)
 505                                 if (FD_ISSET(ctl_sock[i], &readfds)) {
 506                                         addrlen = sizeof(his_addr);
 507                                         fd = accept(ctl_sock[i],
 508                                             (struct sockaddr *)&his_addr,
 509                                             &addrlen);
 510                                         if (fd >= 0) {
 511                                                 if ((pid = fork()) == 0) {
 512                                                         /* child */
 513                                                         (void) dup2(fd, 0);
 514                                                         (void) dup2(fd, 1);
 515                                                         close(ctl_sock[i]);
 516                                                 } else
 517                                                         close(fd);
 518                                         }
 519                                 }
 520                         if (pid == 0)
 521                                 break;
 522                 }
 523         } else {
 524                 addrlen = sizeof(his_addr);
 525                 if (getpeername(0, (struct sockaddr *)&his_addr, &addrlen) < 0) {
 526                         syslog(LOG_ERR, "getpeername (%s): %m",argv[0]);
 527                         exit(1);
 528                 }
 529         }
 530
 531         sa.sa_handler = SIG_DFL;
 532         (void)sigaction(SIGCHLD, &sa, NULL);
 533
 534         sa.sa_handler = sigurg;
 535         sa.sa_flags = 0;                /* don't restart syscalls for SIGURG */
 536         (void)sigaction(SIGURG, &sa, NULL);
 537
 538         sigfillset(&sa.sa_mask);        /* block all signals in handler */
 539         sa.sa_flags = SA_RESTART;
 540         sa.sa_handler = sigquit;
 541         (void)sigaction(SIGHUP, &sa, NULL);
 542         (void)sigaction(SIGINT, &sa, NULL);
 543         (void)sigaction(SIGQUIT, &sa, NULL);
 544         (void)sigaction(SIGTERM, &sa, NULL);
 545
 546         sa.sa_handler = lostconn;
 547         (void)sigaction(SIGPIPE, &sa, NULL);
 548
 549         addrlen = sizeof(ctrl_addr);
 550         if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) {
 551                 syslog(LOG_ERR, "getsockname (%s): %m",argv[0]);
 552                 exit(1);
 553         }
 554         dataport = ntohs(ctrl_addr.su_port) - 1; /* as per RFC 959 */
 555 #ifdef VIRTUAL_HOSTING
 556         /* select our identity from virtual host table */
 557         selecthost(&ctrl_addr);
 558 #endif
 559 #ifdef IP_TOS
 560         if (ctrl_addr.su_family == AF_INET)
 561       {
 562         tos = IPTOS_LOWDELAY;
 563         if (setsockopt(0, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
 564                 syslog(LOG_WARNING, "control setsockopt (IP_TOS): %m");
 565       }
 566 #endif
 567         /*
 568          * Disable Nagle on the control channel so that we don't have to wait
 569          * for peer's ACK before issuing our next reply.
 570          */
 571         if (setsockopt(0, IPPROTO_TCP, TCP_NODELAY, &on, sizeof(on)) < 0)
 572                 syslog(LOG_WARNING, "control setsockopt (TCP_NODELAY): %m");
 573
 574         data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1);
 575
 576         /* set this here so klogin can use it... */
 577         (void)snprintf(ttyline, sizeof(ttyline), "ftp%d", getpid());
 578
 579         /* Try to handle urgent data inline */
 580 #ifdef SO_OOBINLINE
 581         if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, &on, sizeof(on)) < 0)
 582                 syslog(LOG_WARNING, "control setsockopt (SO_OOBINLINE): %m");
 583 #endif
 584
 585 #ifdef  F_SETOWN
 586         if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1)
 587                 syslog(LOG_ERR, "fcntl F_SETOWN: %m");
 588 #endif
 589         dolog((struct sockaddr *)&his_addr);
 590         /*
 591          * Set up default state
 592          */
 593         data = -1;
 594         type = TYPE_A;
 595         form = FORM_N;
 596         stru = STRU_F;
 597         mode = MODE_S;
 598         tmpline[0] = '\0';
 599
 600         /* If logins are disabled, print out the message. */
 601         if ((fd = fopen(_PATH_NOLOGIN,"r")) != NULL) {
 602                 while (fgets(line, sizeof(line), fd) != NULL) {
 603                         if ((cp = strchr(line, '\n')) != NULL)
 604                                 *cp = '\0';
 605                         lreply(530, "%s", line);
 606                 }
 607                 (void) fflush(stdout);
 608                 (void) fclose(fd);
 609                 reply(530, "System not available.");
 610                 exit(0);
 611         }
 612 #ifdef VIRTUAL_HOSTING
 613         fd = fopen(thishost->welcome, "r");
 614 #else
 615         fd = fopen(_PATH_FTPWELCOME, "r");
 616 #endif
 617         if (fd != NULL) {
 618                 while (fgets(line, sizeof(line), fd) != NULL) {
 619                         if ((cp = strchr(line, '\n')) != NULL)
 620                                 *cp = '\0';
 621                         lreply(220, "%s", line);
 622                 }
 623                 (void) fflush(stdout);
 624                 (void) fclose(fd);
 625                 /* reply(220,) must follow */
 626         }
 627 #ifndef VIRTUAL_HOSTING
 628         if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
 629                 fatalerror("Ran out of memory.");
 630         if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
 631                 hostname[0] = '\0';
 632         hostname[MAXHOSTNAMELEN - 1] = '\0';
 633 #endif
 634         if (hostinfo)
 635                 reply(220, "%s FTP server (%s) ready.", hostname, version);
 636         else
 637                 reply(220, "FTP server ready.");
 638         for (;;)
 639                 (void) yyparse();
 640         /* NOTREACHED */
 641 }
 642
 643 static void
 644 lostconn(int signo)
 645 {
 646
 647         if (ftpdebug)
 648                 syslog(LOG_DEBUG, "lost connection");
 649         dologout(1);
 650 }
 651
 652 static void
 653 sigquit(int signo)
 654 {
 655
 656         syslog(LOG_ERR, "got signal %d", signo);
 657         dologout(1);
 658 }
 659
 660 #ifdef VIRTUAL_HOSTING
 661 /*
 662  * read in virtual host tables (if they exist)
 663  */
 664
 665 static void
 666 inithosts(void)
 667 {
 668         int insert;
 669         size_t len;
 670         FILE *fp;
 671         char *cp, *mp, *line;
 672         char *hostname;
 673         char *vhost, *anonuser, *statfile, *welcome, *loginmsg;
 674         struct ftphost *hrp, *lhrp;
 675         struct addrinfo hints, *res, *ai;
 676
 677         /*
 678          * Fill in the default host information
 679          */
 680         if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
 681                 fatalerror("Ran out of memory.");
 682         if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
 683                 hostname[0] = '\0';
 684         hostname[MAXHOSTNAMELEN - 1] = '\0';
 685         if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
 686                 fatalerror("Ran out of memory.");
 687         hrp->hostname = hostname;
 688         hrp->hostinfo = NULL;
 689
 690         memset(&hints, 0, sizeof(hints));
 691         hints.ai_flags = AI_CANONNAME;
 692         hints.ai_family = AF_UNSPEC;
 693         if (getaddrinfo(hrp->hostname, NULL, &hints, &res) == 0)
 694                 hrp->hostinfo = res;
 695         hrp->statfile = _PATH_FTPDSTATFILE;
 696         hrp->welcome  = _PATH_FTPWELCOME;
 697         hrp->loginmsg = _PATH_FTPLOGINMESG;
 698         hrp->anonuser = "ftp";
 699         hrp->next = NULL;
 700         thishost = firsthost = lhrp = hrp;
 701         if ((fp = fopen(_PATH_FTPHOSTS, "r")) != NULL) {
 702                 int addrsize, gothost;
 703                 void *addr;
 704                 struct hostent *hp;
 705
 706                 while ((line = fgetln(fp, &len)) != NULL) {
 707                         int     i, hp_error;
 708
 709                         /* skip comments */
 710                         if (line[0] == '#')
 711                                 continue;
 712                         if (line[len - 1] == '\n') {
 713                                 line[len - 1] = '\0';
 714                                 mp = NULL;
 715                         } else {
 716                                 if ((mp = malloc(len + 1)) == NULL)
 717                                         fatalerror("Ran out of memory.");
 718                                 memcpy(mp, line, len);
 719                                 mp[len] = '\0';
 720                                 line = mp;
 721                         }
 722                         cp = strtok(line, " \t");
 723                         /* skip empty lines */
 724                         if (cp == NULL)
 725                                 goto nextline;
 726                         vhost = cp;
 727
 728                         /* set defaults */
 729                         anonuser = "ftp";
 730                         statfile = _PATH_FTPDSTATFILE;
 731                         welcome  = _PATH_FTPWELCOME;
 732                         loginmsg = _PATH_FTPLOGINMESG;
 733
 734                         /*
 735                          * Preparse the line so we can use its info
 736                          * for all the addresses associated with
 737                          * the virtual host name.
 738                          * Field 0, the virtual host name, is special:
 739                          * it's already parsed off and will be strdup'ed
 740                          * later, after we know its canonical form.
 741                          */
 742                         for (i = 1; i < 5 && (cp = strtok(NULL, " \t")); i++)
 743                                 if (*cp != '-' && (cp = strdup(cp)))
 744                                         switch (i) {
 745                                         case 1: /* anon user permissions */
 746                                                 anonuser = cp;
 747                                                 break;
 748                                         case 2: /* statistics file */
 749                                                 statfile = cp;
 750                                                 break;
 751                                         case 3: /* welcome message */
 752                                                 welcome  = cp;
 753                                                 break;
 754                                         case 4: /* login message */
 755                                                 loginmsg = cp;
 756                                                 break;
 757                                         default: /* programming error */
 758                                                 abort();
 759                                                 /* NOTREACHED */
 760                                         }
 761
 762                         hints.ai_flags = 0;
 763                         hints.ai_family = AF_UNSPEC;
 764                         hints.ai_flags = AI_PASSIVE;
 765                         if (getaddrinfo(vhost, NULL, &hints, &res) != 0)
 766                                 goto nextline;
 767                         for (ai = res; ai != NULL && ai->ai_addr != NULL;
 768                              ai = ai->ai_next) {
 769
 770                         gothost = 0;
 771                         for (hrp = firsthost; hrp != NULL; hrp = hrp->next) {
 772                                 struct addrinfo *hi;
 773
 774                                 for (hi = hrp->hostinfo; hi != NULL;
 775                                      hi = hi->ai_next)
 776                                         if (hi->ai_addrlen == ai->ai_addrlen &&
 777                                             memcmp(hi->ai_addr,
 778                                                    ai->ai_addr,
 779                                                    ai->ai_addr->sa_len) == 0) {
 780                                                 gothost++;
 781                                                 break;
 782                                         }
 783                                 if (gothost)
 784                                         break;
 785                         }
 786                         if (hrp == NULL) {
 787                                 if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
 788                                         goto nextline;
 789                                 hrp->hostname = NULL;
 790                                 insert = 1;
 791                         } else {
 792                                 if (hrp->hostinfo && hrp->hostinfo != res)
 793                                         freeaddrinfo(hrp->hostinfo);
 794                                 insert = 0; /* host already in the chain */
 795                         }
 796                         hrp->hostinfo = res;
 797
 798                         /*
 799                          * determine hostname to use.
 800                          * force defined name if there is a valid alias
 801                          * otherwise fallback to primary hostname
 802                          */
 803                         /* XXX: getaddrinfo() can't do alias check */
 804                         switch(hrp->hostinfo->ai_family) {
 805                         case AF_INET:
 806                                 addr = &((struct sockaddr_in *)hrp->hostinfo->ai_addr)->sin_addr;
 807                                 addrsize = sizeof(struct in_addr);
 808                                 break;
 809                         case AF_INET6:
 810                                 addr = &((struct sockaddr_in6 *)hrp->hostinfo->ai_addr)->sin6_addr;
 811                                 addrsize = sizeof(struct in6_addr);
 812                                 break;
 813                         default:
 814                                 /* should not reach here */
 815                                 freeaddrinfo(hrp->hostinfo);
 816                                 if (insert)
 817                                         free(hrp); /*not in chain, can free*/
 818                                 else
 819                                         hrp->hostinfo = NULL; /*mark as blank*/
 820                                 goto nextline;
 821                                 /* NOTREACHED */
 822                         }
 823                         if ((hp = getipnodebyaddr(addr, addrsize,
 824                                                   hrp->hostinfo->ai_family,
 825                                                   &hp_error)) != NULL) {
 826                                 if (strcmp(vhost, hp->h_name) != 0) {
 827                                         if (hp->h_aliases == NULL)
 828                                                 vhost = hp->h_name;
 829                                         else {
 830                                                 i = 0;
 831                                                 while (hp->h_aliases[i] &&
 832                                                        strcmp(vhost, hp->h_aliases[i]) != 0)
 833                                                         ++i;
 834                                                 if (hp->h_aliases[i] == NULL)
 835                                                         vhost = hp->h_name;
 836                                         }
 837                                 }
 838                         }
 839                         if (hrp->hostname &&
 840                             strcmp(hrp->hostname, vhost) != 0) {
 841                                 free(hrp->hostname);
 842                                 hrp->hostname = NULL;
 843                         }
 844                         if (hrp->hostname == NULL &&
 845                             (hrp->hostname = strdup(vhost)) == NULL) {
 846                                 freeaddrinfo(hrp->hostinfo);
 847                                 hrp->hostinfo = NULL; /* mark as blank */
 848                                 if (hp)
 849                                         freehostent(hp);
 850                                 goto nextline;
 851                         }
 852                         hrp->anonuser = anonuser;
 853                         hrp->statfile = statfile;
 854                         hrp->welcome  = welcome;
 855                         hrp->loginmsg = loginmsg;
 856                         if (insert) {
 857                                 hrp->next  = NULL;
 858                                 lhrp->next = hrp;
 859                                 lhrp = hrp;
 860                         }
 861                         if (hp)
 862                                 freehostent(hp);
 863                       }
 864 nextline:
 865                         if (mp)
 866                                 free(mp);
 867                 }
 868                 (void) fclose(fp);
 869         }
 870 }
 871
 872 static void
 873 selecthost(union sockunion *su)
 874 {
 875         struct ftphost  *hrp;
 876         u_int16_t port;
 877 #ifdef INET6
 878         struct in6_addr *mapped_in6 = NULL;
 879 #endif
 880         struct addrinfo *hi;
 881
 882 #ifdef INET6
 883         /*
 884          * XXX IPv4 mapped IPv6 addr consideraton,
 885          * specified in rfc2373.
 886          */
 887         if (su->su_family == AF_INET6 &&
 888             IN6_IS_ADDR_V4MAPPED(&su->su_sin6.sin6_addr))
 889                 mapped_in6 = &su->su_sin6.sin6_addr;
 890 #endif
 891
 892         hrp = thishost = firsthost;     /* default */
 893         port = su->su_port;
 894         su->su_port = 0;
 895         while (hrp != NULL) {
 896             for (hi = hrp->hostinfo; hi != NULL; hi = hi->ai_next) {
 897                 if (memcmp(su, hi->ai_addr, hi->ai_addrlen) == 0) {
 898                         thishost = hrp;
 899                         goto found;
 900                 }
 901 #ifdef INET6
 902                 /* XXX IPv4 mapped IPv6 addr consideraton */
 903                 if (hi->ai_addr->sa_family == AF_INET && mapped_in6 != NULL &&
 904                     (memcmp(&mapped_in6->s6_addr[12],
 905                             &((struct sockaddr_in *)hi->ai_addr)->sin_addr,
 906                             sizeof(struct in_addr)) == 0)) {
 907                         thishost = hrp;
 908                         goto found;
 909                 }
 910 #endif
 911             }
 912             hrp = hrp->next;
 913         }
 914 found:
 915         su->su_port = port;
 916         /* setup static variables as appropriate */
 917         hostname = thishost->hostname;
 918         ftpuser = thishost->anonuser;
 919 }
 920 #endif
 921
 922 /*
 923  * Helper function for sgetpwnam().
 924  */
 925 static char *
 926 sgetsave(char *s)
 927 {
 928         char *new = malloc(strlen(s) + 1);
 929
 930         if (new == NULL) {
 931                 reply(421, "Ran out of memory.");
 932                 dologout(1);
 933                 /* NOTREACHED */
 934         }
 935         (void) strcpy(new, s);
 936         return (new);
 937 }
 938
 939 /*
 940  * Save the result of a getpwnam.  Used for USER command, since
 941  * the data returned must not be clobbered by any other command
 942  * (e.g., globbing).
 943  * NB: The data returned by sgetpwnam() will remain valid until
 944  * the next call to this function.  Its difference from getpwnam()
 945  * is that sgetpwnam() is known to be called from ftpd code only.
 946  */
 947 static struct passwd *
 948 sgetpwnam(char *name)
 949 {
 950         static struct passwd save;
 951         struct passwd *p;
 952
 953         if ((p = getpwnam(name)) == NULL)
 954                 return (p);
 955         if (save.pw_name) {
 956                 free(save.pw_name);
 957                 free(save.pw_passwd);
 958                 free(save.pw_gecos);
 959                 free(save.pw_dir);
 960                 free(save.pw_shell);
 961         }
 962         save = *p;
 963         save.pw_name = sgetsave(p->pw_name);
 964         save.pw_passwd = sgetsave(p->pw_passwd);
 965         save.pw_gecos = sgetsave(p->pw_gecos);
 966         save.pw_dir = sgetsave(p->pw_dir);
 967         save.pw_shell = sgetsave(p->pw_shell);
 968         return (&save);
 969 }
 970
 971 static int login_attempts;      /* number of failed login attempts */
 972 static int askpasswd;           /* had user command, ask for passwd */
 973 static char curname[MAXLOGNAME];        /* current USER name */
 974
 975 /*
 976  * USER command.
 977  * Sets global passwd pointer pw if named account exists and is acceptable;
 978  * sets askpasswd if a PASS command is expected.  If logged in previously,
 979  * need to reset state.  If name is "ftp" or "anonymous", the name is not in
 980  * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return.
 981  * If account doesn't exist, ask for passwd anyway.  Otherwise, check user
 982  * requesting login privileges.  Disallow anyone who does not have a standard
 983  * shell as returned by getusershell().  Disallow anyone mentioned in the file
 984  * _PATH_FTPUSERS to allow people such as root and uucp to be avoided.
 985  */
 986 void
 987 user(char *name)
 988 {
 989         char *cp, *shell;
 990
 991         if (logged_in) {
 992                 if (guest) {
 993                         reply(530, "Can't change user from guest login.");
 994                         return;
 995                 } else if (dochroot) {
 996                         reply(530, "Can't change user from chroot user.");
 997                         return;
 998                 }
 999                 end_login();
1000         }
1001
1002         guest = 0;
1003 #ifdef VIRTUAL_HOSTING
1004         pw = sgetpwnam(thishost->anonuser);
1005 #else
1006         pw = sgetpwnam("ftp");
1007 #endif
1008         if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) {
1009                 if (checkuser(_PATH_FTPUSERS, "ftp", 0, NULL) ||
1010                     checkuser(_PATH_FTPUSERS, "anonymous", 0, NULL))
1011                         reply(530, "User %s access denied.", name);
1012                 else if (pw != NULL) {
1013                         guest = 1;
1014                         askpasswd = 1;
1015                         reply(331,
1016                         "Guest login ok, send your email address as password.");
1017                 } else
1018                         reply(530, "User %s unknown.", name);
1019                 if (!askpasswd && logging)
1020                         syslog(LOG_NOTICE,
1021                             "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost);
1022                 return;
1023         }
1024         if (anon_only != 0) {
1025                 reply(530, "Sorry, only anonymous ftp allowed.");
1026                 return;
1027         }
1028
1029         if ((pw = sgetpwnam(name))) {
1030                 if ((shell = pw->pw_shell) == NULL || *shell == 0)
1031                         shell = _PATH_BSHELL;
1032                 setusershell();
1033                 while ((cp = getusershell()) != NULL)
1034                         if (strcmp(cp, shell) == 0)
1035                                 break;
1036                 endusershell();
1037
1038                 if (cp == NULL || checkuser(_PATH_FTPUSERS, name, 1, NULL)) {
1039                         reply(530, "User %s access denied.", name);
1040                         if (logging)
1041                                 syslog(LOG_NOTICE,
1042                                     "FTP LOGIN REFUSED FROM %s, %s",
1043                                     remotehost, name);
1044                         pw = NULL;
1045                         return;
1046                 }
1047         }
1048         if (logging)
1049                 strncpy(curname, name, sizeof(curname)-1);
1050
1051         pwok = 0;
1052 #ifdef USE_PAM
1053         /* XXX Kluge! The conversation mechanism needs to be fixed. */
1054 #endif
1055         if (opiechallenge(&opiedata, name, opieprompt) == 0) {
1056                 pwok = (pw != NULL) &&
1057                        opieaccessfile(remotehost) &&
1058                        opiealways(pw->pw_dir);
1059                 reply(331, "Response to %s %s for %s.",
1060                       opieprompt, pwok ? "requested" : "required", name);
1061         } else {
1062                 pwok = 1;
1063                 reply(331, "Password required for %s.", name);
1064         }
1065         askpasswd = 1;
1066         /*
1067          * Delay before reading passwd after first failed
1068          * attempt to slow down passwd-guessing programs.
1069          */
1070         if (login_attempts)
1071                 sleep(login_attempts);
1072 }
1073
1074 /*
1075  * Check if a user is in the file "fname",
1076  * return a pointer to a malloc'd string with the rest
1077  * of the matching line in "residue" if not NULL.
1078  */
1079 static int
1080 checkuser(char *fname, char *name, int pwset, char **residue)
1081 {
1082         FILE *fd;
1083         int found = 0;
1084         size_t len;
1085         char *line, *mp, *p;
1086
1087         if ((fd = fopen(fname, "r")) != NULL) {
1088                 while (!found && (line = fgetln(fd, &len)) != NULL) {
1089                         /* skip comments */
1090                         if (line[0] == '#')
1091                                 continue;
1092                         if (line[len - 1] == '\n') {
1093                                 line[len - 1] = '\0';
1094                                 mp = NULL;
1095                         } else {
1096                                 if ((mp = malloc(len + 1)) == NULL)
1097                                         fatalerror("Ran out of memory.");
1098                                 memcpy(mp, line, len);
1099                                 mp[len] = '\0';
1100                                 line = mp;
1101                         }
1102                         /* avoid possible leading and trailing whitespace */
1103                         p = strtok(line, " \t");
1104                         /* skip empty lines */
1105                         if (p == NULL)
1106                                 goto nextline;
1107                         /*
1108                          * if first chr is '@', check group membership
1109                          */
1110                         if (p[0] == '@') {
1111                                 int i = 0;
1112                                 struct group *grp;
1113
1114                                 if (p[1] == '\0') /* single @ matches anyone */
1115                                         found = 1;
1116                                 else {
1117                                         if ((grp = getgrnam(p+1)) == NULL)
1118                                                 goto nextline;
1119                                         /*
1120                                          * Check user's default group
1121                                          */
1122                                         if (pwset && grp->gr_gid == pw->pw_gid)
1123                                                 found = 1;
1124                                         /*
1125                                          * Check supplementary groups
1126                                          */
1127                                         while (!found && grp->gr_mem[i])
1128                                                 found = strcmp(name,
1129                                                         grp->gr_mem[i++])
1130                                                         == 0;
1131                                 }
1132                         }
1133                         /*
1134                          * Otherwise, just check for username match
1135                          */
1136                         else
1137                                 found = strcmp(p, name) == 0;
1138                         /*
1139                          * Save the rest of line to "residue" if matched
1140                          */
1141                         if (found && residue) {
1142                                 if ((p = strtok(NULL, "")) != NULL)
1143                                         p += strspn(p, " \t");
1144                                 if (p && *p) {
1145                                         if ((*residue = strdup(p)) == NULL)
1146                                                 fatalerror("Ran out of memory.");
1147                                 } else
1148                                         *residue = NULL;
1149                         }
1150 nextline:
1151                         if (mp)
1152                                 free(mp);
1153                 }
1154                 (void) fclose(fd);
1155         }
1156         return (found);
1157 }
1158
1159 /*
1160  * Terminate login as previous user, if any, resetting state;
1161  * used when USER command is given or login fails.
1162  */
1163 static void
1164 end_login(void)
1165 {
1166 #ifdef USE_PAM
1167         int e;
1168 #endif
1169
1170         (void) seteuid(0);
1171         if (logged_in && dowtmp)
1172                 ftpd_logwtmp(ttyline, "", NULL);
1173         pw = NULL;
1174 #ifdef  LOGIN_CAP
1175         setusercontext(NULL, getpwuid(0), 0,
1176                        LOGIN_SETPRIORITY|LOGIN_SETRESOURCES|LOGIN_SETUMASK|
1177                        LOGIN_SETMAC);
1178 #endif
1179 #ifdef USE_PAM
1180         if (pamh) {
1181                 if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS)
1182                         syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1183                 if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS)
1184                         syslog(LOG_ERR, "pam_close_session: %s", pam_strerror(pamh, e));
1185                 if ((e = pam_end(pamh, e)) != PAM_SUCCESS)
1186                         syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1187                 pamh = NULL;
1188         }
1189 #endif
1190         logged_in = 0;
1191         guest = 0;
1192         dochroot = 0;
1193 }
1194
1195 #ifdef USE_PAM
1196
1197 /*
1198  * the following code is stolen from imap-uw PAM authentication module and
1199  * login.c
1200  */
1201 #define COPY_STRING(s) (s ? strdup(s) : NULL)
1202
1203 struct cred_t {
1204         const char *uname;              /* user name */
1205         const char *pass;               /* password */
1206 };
1207 typedef struct cred_t cred_t;
1208
1209 static int
1210 auth_conv(int num_msg, const struct pam_message **msg,
1211           struct pam_response **resp, void *appdata)
1212 {
1213         int i;
1214         cred_t *cred = (cred_t *) appdata;
1215         struct pam_response *reply;
1216
1217         reply = calloc(num_msg, sizeof *reply);
1218         if (reply == NULL)
1219                 return PAM_BUF_ERR;
1220
1221         for (i = 0; i < num_msg; i++) {
1222                 switch (msg[i]->msg_style) {
1223                 case PAM_PROMPT_ECHO_ON:        /* assume want user name */
1224                         reply[i].resp_retcode = PAM_SUCCESS;
1225                         reply[i].resp = COPY_STRING(cred->uname);
1226                         /* PAM frees resp. */
1227                         break;
1228                 case PAM_PROMPT_ECHO_OFF:       /* assume want password */
1229                         reply[i].resp_retcode = PAM_SUCCESS;
1230                         reply[i].resp = COPY_STRING(cred->pass);
1231                         /* PAM frees resp. */
1232                         break;
1233                 case PAM_TEXT_INFO:
1234                 case PAM_ERROR_MSG:
1235                         reply[i].resp_retcode = PAM_SUCCESS;
1236                         reply[i].resp = NULL;
1237                         break;
1238                 default:                        /* unknown message style */
1239                         free(reply);
1240                         return PAM_CONV_ERR;
1241                 }
1242         }
1243
1244         *resp = reply;
1245         return PAM_SUCCESS;
1246 }
1247
1248 /*
1249  * Attempt to authenticate the user using PAM.  Returns 0 if the user is
1250  * authenticated, or 1 if not authenticated.  If some sort of PAM system
1251  * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
1252  * function returns -1.  This can be used as an indication that we should
1253  * fall back to a different authentication mechanism.
1254  */
1255 static int
1256 auth_pam(struct passwd **ppw, const char *pass)
1257 {
1258         const char *tmpl_user;
1259         const void *item;
1260         int rval;
1261         int e;
1262         cred_t auth_cred = { (*ppw)->pw_name, pass };
1263         struct pam_conv conv = { &auth_conv, &auth_cred };
1264
1265         e = pam_start("ftpd", (*ppw)->pw_name, &conv, &pamh);
1266         if (e != PAM_SUCCESS) {
1267                 /*
1268                  * In OpenPAM, it's OK to pass NULL to pam_strerror()
1269                  * if context creation has failed in the first place.
1270                  */
1271                 syslog(LOG_ERR, "pam_start: %s", pam_strerror(NULL, e));
1272                 return -1;
1273         }
1274
1275         e = pam_set_item(pamh, PAM_RHOST, remotehost);
1276         if (e != PAM_SUCCESS) {
1277                 syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
1278                         pam_strerror(pamh, e));
1279                 if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1280                         syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1281                 }
1282                 pamh = NULL;
1283                 return -1;
1284         }
1285
1286         e = pam_authenticate(pamh, 0);
1287         switch (e) {
1288         case PAM_SUCCESS:
1289                 /*
1290                  * With PAM we support the concept of a "template"
1291                  * user.  The user enters a login name which is
1292                  * authenticated by PAM, usually via a remote service
1293                  * such as RADIUS or TACACS+.  If authentication
1294                  * succeeds, a different but related "template" name
1295                  * is used for setting the credentials, shell, and
1296                  * home directory.  The name the user enters need only
1297                  * exist on the remote authentication server, but the
1298                  * template name must be present in the local password
1299                  * database.
1300                  *
1301                  * This is supported by two various mechanisms in the
1302                  * individual modules.  However, from the application's
1303                  * point of view, the template user is always passed
1304                  * back as a changed value of the PAM_USER item.
1305                  */
1306                 if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
1307                     PAM_SUCCESS) {
1308                         tmpl_user = (const char *) item;
1309                         if (strcmp((*ppw)->pw_name, tmpl_user) != 0)
1310                                 *ppw = getpwnam(tmpl_user);
1311                 } else
1312                         syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
1313                             pam_strerror(pamh, e));
1314                 rval = 0;
1315                 break;
1316
1317         case PAM_AUTH_ERR:
1318         case PAM_USER_UNKNOWN:
1319         case PAM_MAXTRIES:
1320                 rval = 1;
1321                 break;
1322
1323         default:
1324                 syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
1325                 rval = -1;
1326                 break;
1327         }
1328
1329         if (rval == 0) {
1330                 e = pam_acct_mgmt(pamh, 0);
1331                 if (e != PAM_SUCCESS) {
1332                         syslog(LOG_ERR, "pam_acct_mgmt: %s",
1333                                                 pam_strerror(pamh, e));
1334                         rval = 1;
1335                 }
1336         }
1337
1338         if (rval != 0) {
1339                 if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1340                         syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1341                 }
1342                 pamh = NULL;
1343         }
1344         return rval;
1345 }
1346
1347 #endif /* USE_PAM */
1348
1349 void
1350 pass(char *passwd)
1351 {
1352         int rval;
1353         FILE *fd;
1354 #ifdef  LOGIN_CAP
1355         login_cap_t *lc = NULL;
1356 #endif
1357 #ifdef USE_PAM
1358         int e;
1359 #endif
1360         char *residue = NULL;
1361         char *xpasswd;
1362
1363         if (logged_in || askpasswd == 0) {
1364                 reply(503, "Login with USER first.");
1365                 return;
1366         }
1367         askpasswd = 0;
1368         if (!guest) {           /* "ftp" is only account allowed no password */
1369                 if (pw == NULL) {
1370                         rval = 1;       /* failure below */
1371                         goto skip;
1372                 }
1373 #ifdef USE_PAM
1374                 rval = auth_pam(&pw, passwd);
1375                 if (rval >= 0) {
1376                         opieunlock();
1377                         goto skip;
1378                 }
1379 #endif
1380                 if (opieverify(&opiedata, passwd) == 0)
1381                         xpasswd = pw->pw_passwd;
1382                 else if (pwok) {
1383                         xpasswd = crypt(passwd, pw->pw_passwd);
1384                         if (passwd[0] == '\0' && pw->pw_passwd[0] != '\0')
1385                                 xpasswd = ":";
1386                 } else {
1387                         rval = 1;
1388                         goto skip;
1389                 }
1390                 rval = strcmp(pw->pw_passwd, xpasswd);
1391                 if (pw->pw_expire && time(NULL) >= pw->pw_expire)
1392                         rval = 1;       /* failure */
1393 skip:
1394                 /*
1395                  * If rval == 1, the user failed the authentication check
1396                  * above.  If rval == 0, either PAM or local authentication
1397                  * succeeded.
1398                  */
1399                 if (rval) {
1400                         reply(530, "Login incorrect.");
1401                         if (logging) {
1402                                 syslog(LOG_NOTICE,
1403                                     "FTP LOGIN FAILED FROM %s",
1404                                     remotehost);
1405                                 syslog(LOG_AUTHPRIV | LOG_NOTICE,
1406                                     "FTP LOGIN FAILED FROM %s, %s",
1407                                     remotehost, curname);
1408                         }
1409                         pw = NULL;
1410                         if (login_attempts++ >= 5) {
1411                                 syslog(LOG_NOTICE,
1412                                     "repeated login failures from %s",
1413                                     remotehost);
1414                                 exit(0);
1415                         }
1416                         return;
1417                 }
1418         }
1419         login_attempts = 0;             /* this time successful */
1420         if (setegid(pw->pw_gid) < 0) {
1421                 reply(550, "Can't set gid.");
1422                 return;
1423         }
1424         /* May be overridden by login.conf */
1425         (void) umask(defumask);
1426 #ifdef  LOGIN_CAP
1427         if ((lc = login_getpwclass(pw)) != NULL) {
1428                 char    remote_ip[NI_MAXHOST];
1429
1430                 if (getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
1431                         remote_ip, sizeof(remote_ip) - 1, NULL, 0,
1432                         NI_NUMERICHOST))
1433                                 *remote_ip = 0;
1434                 remote_ip[sizeof(remote_ip) - 1] = 0;
1435                 if (!auth_hostok(lc, remotehost, remote_ip)) {
1436                         syslog(LOG_INFO|LOG_AUTH,
1437                             "FTP LOGIN FAILED (HOST) as %s: permission denied.",
1438                             pw->pw_name);
1439                         reply(530, "Permission denied.");
1440                         pw = NULL;
1441                         return;
1442                 }
1443                 if (!auth_timeok(lc, time(NULL))) {
1444                         reply(530, "Login not available right now.");
1445                         pw = NULL;
1446                         return;
1447                 }
1448         }
1449         setusercontext(lc, pw, 0,
1450                 LOGIN_SETLOGIN|LOGIN_SETGROUP|LOGIN_SETPRIORITY|
1451                 LOGIN_SETRESOURCES|LOGIN_SETUMASK|LOGIN_SETMAC);
1452 #else
1453         setlogin(pw->pw_name);
1454         (void) initgroups(pw->pw_name, pw->pw_gid);
1455 #endif
1456
1457 #ifdef USE_PAM
1458         if (pamh) {
1459                 if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
1460                         syslog(LOG_ERR, "pam_open_session: %s", pam_strerror(pamh, e));
1461                 } else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED)) != PAM_SUCCESS) {
1462                         syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1463                 }
1464         }
1465 #endif
1466
1467         /* open wtmp before chroot */
1468         if (dowtmp)
1469                 ftpd_logwtmp(ttyline, pw->pw_name,
1470                     (struct sockaddr *)&his_addr);
1471         logged_in = 1;
1472
1473         if (guest && stats && statfd < 0)
1474 #ifdef VIRTUAL_HOSTING
1475                 statfd = open(thishost->statfile, O_WRONLY|O_APPEND);
1476 #else
1477                 statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND);
1478 #endif
1479                 if (statfd < 0)
1480                         stats = 0;
1481
1482         dochroot =
1483                 checkuser(_PATH_FTPCHROOT, pw->pw_name, 1, &residue)
1484 #ifdef  LOGIN_CAP       /* Allow login.conf configuration as well */
1485                 || login_getcapbool(lc, "ftp-chroot", 0)
1486 #endif
1487         ;
1488         chrootdir = NULL;
1489         /*
1490          * For a chrooted local user,
1491          * a) see whether ftpchroot(5) specifies a chroot directory,
1492          * b) extract the directory pathname from the line,
1493          * c) expand it to the absolute pathname if necessary.
1494          */
1495         if (dochroot && residue &&
1496             (chrootdir = strtok(residue, " \t")) != NULL) {
1497                 if (chrootdir[0] != '/')
1498                         asprintf(&chrootdir, "%s/%s", pw->pw_dir, chrootdir);
1499                 else
1500                         chrootdir = strdup(chrootdir); /* make it permanent */
1501                 if (chrootdir == NULL)
1502                         fatalerror("Ran out of memory.");
1503         }
1504         if (guest || dochroot) {
1505                 /*
1506                  * If no chroot directory set yet, use the login directory.
1507                  * Copy it so it can be modified while pw->pw_dir stays intact.
1508                  */
1509                 if (chrootdir == NULL &&
1510                     (chrootdir = strdup(pw->pw_dir)) == NULL)
1511                         fatalerror("Ran out of memory.");
1512                 /*
1513                  * Check for the "/chroot/./home" syntax,
1514                  * separate the chroot and home directory pathnames.
1515                  */
1516                 if ((homedir = strstr(chrootdir, "/./")) != NULL) {
1517                         *(homedir++) = '\0';    /* wipe '/' */
1518                         homedir++;              /* skip '.' */
1519                 } else {
1520                         /*
1521                          * We MUST do a chdir() after the chroot. Otherwise
1522                          * the old current directory will be accessible as "."
1523                          * outside the new root!
1524                          */
1525                         homedir = "/";
1526                 }
1527                 /*
1528                  * Finally, do chroot()
1529                  */
1530                 if (chroot(chrootdir) < 0) {
1531                         reply(550, "Can't change root.");
1532                         goto bad;
1533                 }
1534         } else  /* real user w/o chroot */
1535                 homedir = pw->pw_dir;
1536         /*
1537          * Set euid *before* doing chdir() so
1538          * a) the user won't be carried to a directory that he couldn't reach
1539          *    on his own due to no permission to upper path components,
1540          * b) NFS mounted homedirs w/restrictive permissions will be accessible
1541          *    (uid 0 has no root power over NFS if not mapped explicitly.)
1542          */
1543         if (seteuid(pw->pw_uid) < 0) {
1544                 reply(550, "Can't set uid.");
1545                 goto bad;
1546         }
1547         if (chdir(homedir) < 0) {
1548                 if (guest || dochroot) {
1549                         reply(550, "Can't change to base directory.");
1550                         goto bad;
1551                 } else {
1552                         if (chdir("/") < 0) {
1553                                 reply(550, "Root is inaccessible.");
1554                                 goto bad;
1555                         }
1556                         lreply(230, "No directory! Logging in with home=/.");
1557                 }
1558         }
1559
1560         /*
1561          * Display a login message, if it exists.
1562          * N.B. reply(230,) must follow the message.
1563          */
1564 #ifdef VIRTUAL_HOSTING
1565         fd = fopen(thishost->loginmsg, "r");
1566 #else
1567         fd = fopen(_PATH_FTPLOGINMESG, "r");
1568 #endif
1569         if (fd != NULL) {
1570                 char *cp, line[LINE_MAX];
1571
1572                 while (fgets(line, sizeof(line), fd) != NULL) {
1573                         if ((cp = strchr(line, '\n')) != NULL)
1574                                 *cp = '\0';
1575                         lreply(230, "%s", line);
1576                 }
1577                 (void) fflush(stdout);
1578                 (void) fclose(fd);
1579         }
1580         if (guest) {
1581                 if (ident != NULL)
1582                         free(ident);
1583                 ident = strdup(passwd);
1584                 if (ident == NULL)
1585                         fatalerror("Ran out of memory.");
1586
1587                 reply(230, "Guest login ok, access restrictions apply.");
1588 #ifdef SETPROCTITLE
1589 #ifdef VIRTUAL_HOSTING
1590                 if (thishost != firsthost)
1591                         snprintf(proctitle, sizeof(proctitle),
1592                                  "%s: anonymous(%s)/%s", remotehost, hostname,
1593                                  passwd);
1594                 else
1595 #endif
1596                         snprintf(proctitle, sizeof(proctitle),
1597                                  "%s: anonymous/%s", remotehost, passwd);
1598                 setproctitle("%s", proctitle);
1599 #endif /* SETPROCTITLE */
1600                 if (logging)
1601                         syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s",
1602                             remotehost, passwd);
1603         } else {
1604                 if (dochroot)
1605                         reply(230, "User %s logged in, "
1606                                    "access restrictions apply.", pw->pw_name);
1607                 else
1608                         reply(230, "User %s logged in.", pw->pw_name);
1609
1610 #ifdef SETPROCTITLE
1611                 snprintf(proctitle, sizeof(proctitle),
1612                          "%s: user/%s", remotehost, pw->pw_name);
1613                 setproctitle("%s", proctitle);
1614 #endif /* SETPROCTITLE */
1615                 if (logging)
1616                         syslog(LOG_INFO, "FTP LOGIN FROM %s as %s",
1617                             remotehost, pw->pw_name);
1618         }
1619         if (logging && (guest || dochroot))
1620                 syslog(LOG_INFO, "session root changed to %s", chrootdir);
1621 #ifdef  LOGIN_CAP
1622         login_close(lc);
1623 #endif
1624         if (residue)
1625                 free(residue);
1626         return;
1627 bad:
1628         /* Forget all about it... */
1629 #ifdef  LOGIN_CAP
1630         login_close(lc);
1631 #endif
1632         if (residue)
1633                 free(residue);
1634         end_login();
1635 }
1636
1637 void
1638 retrieve(char *cmd, char *name)
1639 {
1640         FILE *fin, *dout;
1641         struct stat st;
1642         int (*closefunc)(FILE *);
1643         time_t start;
1644
1645         if (cmd == 0) {
1646                 fin = fopen(name, "r"), closefunc = fclose;
1647                 st.st_size = 0;
1648         } else {
1649                 char line[BUFSIZ];
1650
1651                 (void) snprintf(line, sizeof(line), cmd, name), name = line;
1652                 fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose;
1653                 st.st_size = -1;
1654                 st.st_blksize = BUFSIZ;
1655         }
1656         if (fin == NULL) {
1657                 if (errno != 0) {
1658                         perror_reply(550, name);
1659                         if (cmd == 0) {
1660                                 LOGCMD("get", name);
1661                         }
1662                 }
1663                 return;
1664         }
1665         byte_count = -1;
1666         if (cmd == 0) {
1667                 if (fstat(fileno(fin), &st) < 0) {
1668                         perror_reply(550, name);
1669                         goto done;
1670                 }
1671                 if (!S_ISREG(st.st_mode)) {
1672                         /*
1673                          * Never sending a raw directory is a workaround
1674                          * for buggy clients that will attempt to RETR
1675                          * a directory before listing it, e.g., Mozilla.
1676                          * Preventing a guest from getting irregular files
1677                          * is a simple security measure.
1678                          */
1679                         if (S_ISDIR(st.st_mode) || guest) {
1680                                 reply(550, "%s: not a plain file.", name);
1681                                 goto done;
1682                         }
1683                         st.st_size = -1;
1684                         /* st.st_blksize is set for all descriptor types */
1685                 }
1686         }
1687         if (restart_point) {
1688                 if (type == TYPE_A) {
1689                         off_t i, n;
1690                         int c;
1691
1692                         n = restart_point;
1693                         i = 0;
1694                         while (i++ < n) {
1695                                 if ((c=getc(fin)) == EOF) {
1696                                         perror_reply(550, name);
1697                                         goto done;
1698                                 }
1699                                 if (c == '\n')
1700                                         i++;
1701                         }
1702                 } else if (lseek(fileno(fin), restart_point, L_SET) < 0) {
1703                         perror_reply(550, name);
1704                         goto done;
1705                 }
1706         }
1707         dout = dataconn(name, st.st_size, "w");
1708         if (dout == NULL)
1709                 goto done;
1710         time(&start);
1711         send_data(fin, dout, st.st_blksize, st.st_size,
1712                   restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode));
1713         if (cmd == 0 && guest && stats && byte_count > 0)
1714                 logxfer(name, byte_count, start);
1715         (void) fclose(dout);
1716         data = -1;
1717         pdata = -1;
1718 done:
1719         if (cmd == 0)
1720                 LOGBYTES("get", name, byte_count);
1721         (*closefunc)(fin);
1722 }
1723
1724 void
1725 store(char *name, char *mode, int unique)
1726 {
1727         int fd;
1728         FILE *fout, *din;
1729         int (*closefunc)(FILE *);
1730
1731         if (*mode == 'a') {             /* APPE */
1732                 if (unique) {
1733                         /* Programming error */
1734                         syslog(LOG_ERR, "Internal: unique flag to APPE");
1735                         unique = 0;
1736                 }
1737                 if (guest && noguestmod) {
1738                         reply(550, "Appending to existing file denied.");
1739                         goto err;
1740                 }
1741                 restart_point = 0;      /* not affected by preceding REST */
1742         }
1743         if (unique)                     /* STOU overrides REST */
1744                 restart_point = 0;
1745         if (guest && noguestmod) {
1746                 if (restart_point) {    /* guest STOR w/REST */
1747                         reply(550, "Modifying existing file denied.");
1748                         goto err;
1749                 } else                  /* treat guest STOR as STOU */
1750                         unique = 1;
1751         }
1752
1753         if (restart_point)
1754                 mode = "r+";    /* so ASCII manual seek can work */
1755         if (unique) {
1756                 if ((fd = guniquefd(name, &name)) < 0)
1757                         goto err;
1758                 fout = fdopen(fd, mode);
1759         } else
1760                 fout = fopen(name, mode);
1761         closefunc = fclose;
1762         if (fout == NULL) {
1763                 perror_reply(553, name);
1764                 goto err;
1765         }
1766         byte_count = -1;
1767         if (restart_point) {
1768                 if (type == TYPE_A) {
1769                         off_t i, n;
1770                         int c;
1771
1772                         n = restart_point;
1773                         i = 0;
1774                         while (i++ < n) {
1775                                 if ((c=getc(fout)) == EOF) {
1776                                         perror_reply(550, name);
1777                                         goto done;
1778                                 }
1779                                 if (c == '\n')
1780                                         i++;
1781                         }
1782                         /*
1783                          * We must do this seek to "current" position
1784                          * because we are changing from reading to
1785                          * writing.
1786                          */
1787                         if (fseeko(fout, 0, SEEK_CUR) < 0) {
1788                                 perror_reply(550, name);
1789                                 goto done;
1790                         }
1791                 } else if (lseek(fileno(fout), restart_point, L_SET) < 0) {
1792                         perror_reply(550, name);
1793                         goto done;
1794                 }
1795         }
1796         din = dataconn(name, -1, "r");
1797         if (din == NULL)
1798                 goto done;
1799         if (receive_data(din, fout) == 0) {
1800                 if (unique)
1801                         reply(226, "Transfer complete (unique file name:%s).",
1802                             name);
1803                 else
1804                         reply(226, "Transfer complete.");
1805         }
1806         (void) fclose(din);
1807         data = -1;
1808         pdata = -1;
1809 done:
1810         LOGBYTES(*mode == 'a' ? "append" : "put", name, byte_count);
1811         (*closefunc)(fout);
1812         return;
1813 err:
1814         LOGCMD(*mode == 'a' ? "append" : "put" , name);
1815         return;
1816 }
1817
1818 static FILE *
1819 getdatasock(char *mode)
1820 {
1821         int on = 1, s, t, tries;
1822
1823         if (data >= 0)
1824                 return (fdopen(data, mode));
1825
1826         s = socket(data_dest.su_family, SOCK_STREAM, 0);
1827         if (s < 0)
1828                 goto bad;
1829         if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
1830                 syslog(LOG_WARNING, "data setsockopt (SO_REUSEADDR): %m");
1831         /* anchor socket to avoid multi-homing problems */
1832         data_source = ctrl_addr;
1833         data_source.su_port = htons(dataport);
1834         (void) seteuid(0);
1835         for (tries = 1; ; tries++) {
1836                 /*
1837                  * We should loop here since it's possible that
1838                  * another ftpd instance has passed this point and is
1839                  * trying to open a data connection in active mode now.
1840                  * Until the other connection is opened, we'll be getting
1841                  * EADDRINUSE because no SOCK_STREAM sockets in the system
1842                  * can share both local and remote addresses, localIP:20
1843                  * and *:* in this case.
1844                  */
1845                 if (bind(s, (struct sockaddr *)&data_source,
1846                     data_source.su_len) >= 0)
1847                         break;
1848                 if (errno != EADDRINUSE || tries > 10)
1849                         goto bad;
1850                 sleep(tries);
1851         }
1852         (void) seteuid(pw->pw_uid);
1853 #ifdef IP_TOS
1854         if (data_source.su_family == AF_INET)
1855       {
1856         on = IPTOS_THROUGHPUT;
1857         if (setsockopt(s, IPPROTO_IP, IP_TOS, &on, sizeof(int)) < 0)
1858                 syslog(LOG_WARNING, "data setsockopt (IP_TOS): %m");
1859       }
1860 #endif
1861 #ifdef TCP_NOPUSH
1862         /*
1863          * Turn off push flag to keep sender TCP from sending short packets
1864          * at the boundaries of each write().  Should probably do a SO_SNDBUF
1865          * to set the send buffer size as well, but that may not be desirable
1866          * in heavy-load situations.
1867          */
1868         on = 1;
1869         if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, &on, sizeof on) < 0)
1870                 syslog(LOG_WARNING, "data setsockopt (TCP_NOPUSH): %m");
1871 #endif
1872 #ifdef SO_SNDBUF
1873         on = 65536;
1874         if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, &on, sizeof on) < 0)
1875                 syslog(LOG_WARNING, "data setsockopt (SO_SNDBUF): %m");
1876 #endif
1877
1878         return (fdopen(s, mode));
1879 bad:
1880         /* Return the real value of errno (close may change it) */
1881         t = errno;
1882         (void) seteuid(pw->pw_uid);
1883         (void) close(s);
1884         errno = t;
1885         return (NULL);
1886 }
1887
1888 static FILE *
1889 dataconn(char *name, off_t size, char *mode)
1890 {
1891         char sizebuf[32];
1892         FILE *file;
1893         int retry = 0, tos, conerrno;
1894
1895         file_size = size;
1896         byte_count = 0;
1897         if (size != -1)
1898                 (void) snprintf(sizebuf, sizeof(sizebuf),
1899                                 " (%jd bytes)", (intmax_t)size);
1900         else
1901                 *sizebuf = '\0';
1902         if (pdata >= 0) {
1903                 union sockunion from;
1904                 socklen_t fromlen = ctrl_addr.su_len;
1905                 int flags, s;
1906                 struct timeval timeout;
1907                 fd_set set;
1908
1909                 FD_ZERO(&set);
1910                 FD_SET(pdata, &set);
1911
1912                 timeout.tv_usec = 0;
1913                 timeout.tv_sec = 120;
1914
1915                 /*
1916                  * Granted a socket is in the blocking I/O mode,
1917                  * accept() will block after a successful select()
1918                  * if the selected connection dies in between.
1919                  * Therefore set the non-blocking I/O flag here.
1920                  */
1921                 if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1922                     fcntl(pdata, F_SETFL, flags | O_NONBLOCK) == -1)
1923                         goto pdata_err;
1924                 if (select(pdata+1, &set, NULL, NULL, &timeout) <= 0 ||
1925                     (s = accept(pdata, (struct sockaddr *) &from, &fromlen)) < 0)
1926                         goto pdata_err;
1927                 (void) close(pdata);
1928                 pdata = s;
1929                 /*
1930                  * Unset the inherited non-blocking I/O flag
1931                  * on the child socket so stdio can work on it.
1932                  */
1933                 if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1934                     fcntl(pdata, F_SETFL, flags & ~O_NONBLOCK) == -1)
1935                         goto pdata_err;
1936 #ifdef IP_TOS
1937                 if (from.su_family == AF_INET)
1938               {
1939                 tos = IPTOS_THROUGHPUT;
1940                 if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
1941                         syslog(LOG_WARNING, "pdata setsockopt (IP_TOS): %m");
1942               }
1943 #endif
1944                 reply(150, "Opening %s mode data connection for '%s'%s.",
1945                      type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
1946                 return (fdopen(pdata, mode));
1947 pdata_err:
1948                 reply(425, "Can't open data connection.");
1949                 (void) close(pdata);
1950                 pdata = -1;
1951                 return (NULL);
1952         }
1953         if (data >= 0) {
1954                 reply(125, "Using existing data connection for '%s'%s.",
1955                     name, sizebuf);
1956                 usedefault = 1;
1957                 return (fdopen(data, mode));
1958         }
1959         if (usedefault)
1960                 data_dest = his_addr;
1961         usedefault = 1;
1962         do {
1963                 file = getdatasock(mode);
1964                 if (file == NULL) {
1965                         char hostbuf[NI_MAXHOST], portbuf[NI_MAXSERV];
1966
1967                         if (getnameinfo((struct sockaddr *)&data_source,
1968                                 data_source.su_len,
1969                                 hostbuf, sizeof(hostbuf) - 1,
1970                                 portbuf, sizeof(portbuf) - 1,
1971                                 NI_NUMERICHOST|NI_NUMERICSERV))
1972                                         *hostbuf = *portbuf = 0;
1973                         hostbuf[sizeof(hostbuf) - 1] = 0;
1974                         portbuf[sizeof(portbuf) - 1] = 0;
1975                         reply(425, "Can't create data socket (%s,%s): %s.",
1976                                 hostbuf, portbuf, strerror(errno));
1977                         return (NULL);
1978                 }
1979                 data = fileno(file);
1980                 conerrno = 0;
1981                 if (connect(data, (struct sockaddr *)&data_dest,
1982                     data_dest.su_len) == 0)
1983                         break;
1984                 conerrno = errno;
1985                 (void) fclose(file);
1986                 data = -1;
1987                 if (conerrno == EADDRINUSE) {
1988                         sleep(swaitint);
1989                         retry += swaitint;
1990                 } else {
1991                         break;
1992                 }
1993         } while (retry <= swaitmax);
1994         if (conerrno != 0) {
1995                 reply(425, "Can't build data connection: %s.",
1996                            strerror(conerrno));
1997                 return (NULL);
1998         }
1999         reply(150, "Opening %s mode data connection for '%s'%s.",
2000              type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
2001         return (file);
2002 }
2003
2004 /*
2005  * A helper macro to avoid code duplication
2006  * in send_data() and receive_data().
2007  *
2008  * XXX We have to block SIGURG during putc() because BSD stdio
2009  * is unable to restart interrupted write operations and hence
2010  * the entire buffer contents will be lost as soon as a write()
2011  * call indicates EINTR to stdio.
2012  */
2013 #define FTPD_PUTC(ch, file, label)                                      \
2014         do {                                                            \
2015                 int ret;                                                \
2016                                                                         \
2017                 do {                                                    \
2018                         START_UNSAFE;                                   \
2019                         ret = putc((ch), (file));                       \
2020                         END_UNSAFE;                                     \
2021                         CHECKOOB(return (-1))                           \
2022                         else if (ferror(file))                          \
2023                                 goto label;                             \
2024                         clearerr(file);                                 \
2025                 } while (ret == EOF);                                   \
2026         } while (0)
2027
2028 /*
2029  * Tranfer the contents of "instr" to "outstr" peer using the appropriate
2030  * encapsulation of the data subject to Mode, Structure, and Type.
2031  *
2032  * NB: Form isn't handled.
2033  */
2034 static int
2035 send_data(FILE *instr, FILE *outstr, size_t blksize, off_t filesize, int isreg)
2036 {
2037         int c, cp, filefd, netfd;
2038         char *buf;
2039
2040         STARTXFER;
2041
2042         switch (type) {
2043
2044         case TYPE_A:
2045                 cp = EOF;
2046                 for (;;) {
2047                         c = getc(instr);
2048                         CHECKOOB(return (-1))
2049                         else if (c == EOF && ferror(instr))
2050                                 goto file_err;
2051                         if (c == EOF) {
2052                                 if (ferror(instr)) {    /* resume after OOB */
2053                                         clearerr(instr);
2054                                         continue;
2055                                 }
2056                                 if (feof(instr))        /* EOF */
2057                                         break;
2058                                 syslog(LOG_ERR, "Internal: impossible condition"
2059                                                 " on file after getc()");
2060                                 goto file_err;
2061                         }
2062                         if (c == '\n' && cp != '\r') {
2063                                 FTPD_PUTC('\r', outstr, data_err);
2064                                 byte_count++;
2065                         }
2066                         FTPD_PUTC(c, outstr, data_err);
2067                         byte_count++;
2068                         cp = c;
2069                 }
2070 #ifdef notyet   /* BSD stdio isn't ready for that */
2071                 while (fflush(outstr) == EOF) {
2072                         CHECKOOB(return (-1))
2073                         else
2074                                 goto data_err;
2075                         clearerr(outstr);
2076                 }
2077                 ENDXFER;
2078 #else
2079                 ENDXFER;
2080                 if (fflush(outstr) == EOF)
2081                         goto data_err;
2082 #endif
2083                 reply(226, "Transfer complete.");
2084                 return (0);
2085
2086         case TYPE_I:
2087         case TYPE_L:
2088                 /*
2089                  * isreg is only set if we are not doing restart and we
2090                  * are sending a regular file
2091                  */
2092                 netfd = fileno(outstr);
2093                 filefd = fileno(instr);
2094
2095                 if (isreg) {
2096                         char *msg = "Transfer complete.";
2097                         off_t cnt, offset;
2098                         int err;
2099
2100                         cnt = offset = 0;
2101
2102                         while (filesize > 0) {
2103                                 err = sendfile(filefd, netfd, offset, 0,
2104                                                NULL, &cnt, 0);
2105                                 /*
2106                                  * Calculate byte_count before OOB processing.
2107                                  * It can be used in myoob() later.
2108                                  */
2109                                 byte_count += cnt;
2110                                 offset += cnt;
2111                                 filesize -= cnt;
2112                                 CHECKOOB(return (-1))
2113                                 else if (err == -1) {
2114                                         if (errno != EINTR &&
2115                                             cnt == 0 && offset == 0)
2116                                                 goto oldway;
2117                                         goto data_err;
2118                                 }
2119                                 if (err == -1)  /* resume after OOB */
2120                                         continue;
2121                                 /*
2122                                  * We hit the EOF prematurely.
2123                                  * Perhaps the file was externally truncated.
2124                                  */
2125                                 if (cnt == 0) {
2126                                         msg = "Transfer finished due to "
2127                                               "premature end of file.";
2128                                         break;
2129                                 }
2130                         }
2131                         ENDXFER;
2132                         reply(226, msg);
2133                         return (0);
2134                 }
2135
2136 oldway:
2137                 if ((buf = malloc(blksize)) == NULL) {
2138                         ENDXFER;
2139                         reply(451, "Ran out of memory.");
2140                         return (-1);
2141                 }
2142
2143                 for (;;) {
2144                         int cnt, len;
2145                         char *bp;
2146
2147                         cnt = read(filefd, buf, blksize);
2148                         CHECKOOB(free(buf); return (-1))
2149                         else if (cnt < 0) {
2150                                 free(buf);
2151                                 goto file_err;
2152                         }
2153                         if (cnt < 0)    /* resume after OOB */
2154                                 continue;
2155                         if (cnt == 0)   /* EOF */
2156                                 break;
2157                         for (len = cnt, bp = buf; len > 0;) {
2158                                 cnt = write(netfd, bp, len);
2159                                 CHECKOOB(free(buf); return (-1))
2160                                 else if (cnt < 0) {
2161                                         free(buf);
2162                                         goto data_err;
2163                                 }
2164                                 if (cnt <= 0)
2165                                         continue;
2166                                 len -= cnt;
2167                                 bp += cnt;
2168                                 byte_count += cnt;
2169                         }
2170                 }
2171                 ENDXFER;
2172                 free(buf);
2173                 reply(226, "Transfer complete.");
2174                 return (0);
2175         default:
2176                 ENDXFER;
2177                 reply(550, "Unimplemented TYPE %d in send_data.", type);
2178                 return (-1);
2179         }
2180
2181 data_err:
2182         ENDXFER;
2183         perror_reply(426, "Data connection");
2184         return (-1);
2185
2186 file_err:
2187         ENDXFER;
2188         perror_reply(551, "Error on input file");
2189         return (-1);
2190 }
2191
2192 /*
2193  * Transfer data from peer to "outstr" using the appropriate encapulation of
2194  * the data subject to Mode, Structure, and Type.
2195  *
2196  * N.B.: Form isn't handled.
2197  */
2198 static int
2199 receive_data(FILE *instr, FILE *outstr)
2200 {
2201         int c, cp;
2202         int bare_lfs = 0;
2203
2204         STARTXFER;
2205
2206         switch (type) {
2207
2208         case TYPE_I:
2209         case TYPE_L:
2210                 for (;;) {
2211                         int cnt, len;
2212                         char *bp;
2213                         char buf[BUFSIZ];
2214
2215                         cnt = read(fileno(instr), buf, sizeof(buf));
2216                         CHECKOOB(return (-1))
2217                         else if (cnt < 0)
2218                                 goto data_err;
2219                         if (cnt < 0)    /* resume after OOB */
2220                                 continue;
2221                         if (cnt == 0)   /* EOF */
2222                                 break;
2223                         for (len = cnt, bp = buf; len > 0;) {
2224                                 cnt = write(fileno(outstr), bp, len);
2225                                 CHECKOOB(return (-1))
2226                                 else if (cnt < 0)
2227                                         goto file_err;
2228                                 if (cnt <= 0)
2229                                         continue;
2230                                 len -= cnt;
2231                                 bp += cnt;
2232                                 byte_count += cnt;
2233                         }
2234                 }
2235                 ENDXFER;
2236                 return (0);
2237
2238         case TYPE_E:
2239                 ENDXFER;
2240                 reply(553, "TYPE E not implemented.");
2241                 return (-1);
2242
2243         case TYPE_A:
2244                 cp = EOF;
2245                 for (;;) {
2246                         c = getc(instr);
2247                         CHECKOOB(return (-1))
2248                         else if (c == EOF && ferror(instr))
2249                                 goto data_err;
2250                         if (c == EOF && ferror(instr)) { /* resume after OOB */
2251                                 clearerr(instr);
2252                                 continue;
2253                         }
2254
2255                         if (cp == '\r') {
2256                                 if (c != '\n')
2257                                         FTPD_PUTC('\r', outstr, file_err);
2258                         } else
2259                                 if (c == '\n')
2260                                         bare_lfs++;
2261                         if (c == '\r') {
2262                                 byte_count++;
2263                                 cp = c;
2264                                 continue;
2265                         }
2266
2267                         /* Check for EOF here in order not to lose last \r. */
2268                         if (c == EOF) {
2269                                 if (feof(instr))        /* EOF */
2270                                         break;
2271                                 syslog(LOG_ERR, "Internal: impossible condition"
2272                                                 " on data stream after getc()");
2273                                 goto data_err;
2274                         }
2275
2276                         byte_count++;
2277                         FTPD_PUTC(c, outstr, file_err);
2278                         cp = c;
2279                 }
2280 #ifdef notyet   /* BSD stdio isn't ready for that */
2281                 while (fflush(outstr) == EOF) {
2282                         CHECKOOB(return (-1))
2283                         else
2284                                 goto file_err;
2285                         clearerr(outstr);
2286                 }
2287                 ENDXFER;
2288 #else
2289                 ENDXFER;
2290                 if (fflush(outstr) == EOF)
2291                         goto file_err;
2292 #endif
2293                 if (bare_lfs) {
2294                         lreply(226,
2295                 "WARNING! %d bare linefeeds received in ASCII mode.",
2296                             bare_lfs);
2297                 (void)printf("   File may not have transferred correctly.\r\n");
2298                 }
2299                 return (0);
2300         default:
2301                 ENDXFER;
2302                 reply(550, "Unimplemented TYPE %d in receive_data.", type);
2303                 return (-1);
2304         }
2305
2306 data_err:
2307         ENDXFER;
2308         perror_reply(426, "Data connection");
2309         return (-1);
2310
2311 file_err:
2312         ENDXFER;
2313         perror_reply(452, "Error writing to file");
2314         return (-1);
2315 }
2316
2317 void
2318 statfilecmd(char *filename)
2319 {
2320         FILE *fin;
2321         int atstart;
2322         int c, code;
2323         char line[LINE_MAX];
2324         struct stat st;
2325
2326         code = lstat(filename, &st) == 0 && S_ISDIR(st.st_mode) ? 212 : 213;
2327         (void)snprintf(line, sizeof(line), _PATH_LS " -lgA %s", filename);
2328         fin = ftpd_popen(line, "r");
2329         lreply(code, "Status of %s:", filename);
2330         atstart = 1;
2331         while ((c = getc(fin)) != EOF) {
2332                 if (c == '\n') {
2333                         if (ferror(stdout)){
2334                                 perror_reply(421, "Control connection");
2335                                 (void) ftpd_pclose(fin);
2336                                 dologout(1);
2337                                 /* NOTREACHED */
2338                         }
2339                         if (ferror(fin)) {
2340                                 perror_reply(551, filename);
2341                                 (void) ftpd_pclose(fin);
2342                                 return;
2343                         }
2344                         (void) putc('\r', stdout);
2345                 }
2346                 /*
2347                  * RFC 959 says neutral text should be prepended before
2348                  * a leading 3-digit number followed by whitespace, but
2349                  * many ftp clients can be confused by any leading digits,
2350                  * as a matter of fact.
2351                  */
2352                 if (atstart && isdigit(c))
2353                         (void) putc(' ', stdout);
2354                 (void) putc(c, stdout);
2355                 atstart = (c == '\n');
2356         }
2357         (void) ftpd_pclose(fin);
2358         reply(code, "End of status.");
2359 }
2360
2361 void
2362 statcmd(void)
2363 {
2364         union sockunion *su;
2365         u_char *a, *p;
2366         char hname[NI_MAXHOST];
2367         int ispassive;
2368
2369         if (hostinfo) {
2370                 lreply(211, "%s FTP server status:", hostname);
2371                 printf("     %s\r\n", version);
2372         } else
2373                 lreply(211, "FTP server status:");
2374         printf("     Connected to %s", remotehost);
2375         if (!getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
2376                          hname, sizeof(hname) - 1, NULL, 0, NI_NUMERICHOST)) {
2377                 hname[sizeof(hname) - 1] = 0;
2378                 if (strcmp(hname, remotehost) != 0)
2379                         printf(" (%s)", hname);
2380         }
2381         printf("\r\n");
2382         if (logged_in) {
2383                 if (guest)
2384                         printf("     Logged in anonymously\r\n");
2385                 else
2386                         printf("     Logged in as %s\r\n", pw->pw_name);
2387         } else if (askpasswd)
2388                 printf("     Waiting for password\r\n");
2389         else
2390                 printf("     Waiting for user name\r\n");
2391         printf("     TYPE: %s", typenames[type]);
2392         if (type == TYPE_A || type == TYPE_E)
2393                 printf(", FORM: %s", formnames[form]);
2394         if (type == TYPE_L)
2395 #if CHAR_BIT == 8
2396                 printf(" %d", CHAR_BIT);
2397 #else
2398                 printf(" %d", bytesize);        /* need definition! */
2399 #endif
2400         printf("; STRUcture: %s; transfer MODE: %s\r\n",
2401             strunames[stru], modenames[mode]);
2402         if (data != -1)
2403                 printf("     Data connection open\r\n");
2404         else if (pdata != -1) {
2405                 ispassive = 1;
2406                 su = &pasv_addr;
2407                 goto printaddr;
2408         } else if (usedefault == 0) {
2409                 ispassive = 0;
2410                 su = &data_dest;
2411 printaddr:
2412 #define UC(b) (((int) b) & 0xff)
2413                 if (epsvall) {
2414                         printf("     EPSV only mode (EPSV ALL)\r\n");
2415                         goto epsvonly;
2416                 }
2417
2418                 /* PORT/PASV */
2419                 if (su->su_family == AF_INET) {
2420                         a = (u_char *) &su->su_sin.sin_addr;
2421                         p = (u_char *) &su->su_sin.sin_port;
2422                         printf("     %s (%d,%d,%d,%d,%d,%d)\r\n",
2423                                 ispassive ? "PASV" : "PORT",
2424                                 UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2425                                 UC(p[0]), UC(p[1]));
2426                 }
2427
2428                 /* LPRT/LPSV */
2429             {
2430                 int alen, af, i;
2431
2432                 switch (su->su_family) {
2433                 case AF_INET:
2434                         a = (u_char *) &su->su_sin.sin_addr;
2435                         p = (u_char *) &su->su_sin.sin_port;
2436                         alen = sizeof(su->su_sin.sin_addr);
2437                         af = 4;
2438                         break;
2439                 case AF_INET6:
2440                         a = (u_char *) &su->su_sin6.sin6_addr;
2441                         p = (u_char *) &su->su_sin6.sin6_port;
2442                         alen = sizeof(su->su_sin6.sin6_addr);
2443                         af = 6;
2444                         break;
2445                 default:
2446                         af = 0;
2447                         break;
2448                 }
2449                 if (af) {
2450                         printf("     %s (%d,%d,", ispassive ? "LPSV" : "LPRT",
2451                                 af, alen);
2452                         for (i = 0; i < alen; i++)
2453                                 printf("%d,", UC(a[i]));
2454                         printf("%d,%d,%d)\r\n", 2, UC(p[0]), UC(p[1]));
2455                 }
2456             }
2457
2458 epsvonly:;
2459                 /* EPRT/EPSV */
2460             {
2461                 int af;
2462
2463                 switch (su->su_family) {
2464                 case AF_INET:
2465                         af = 1;
2466                         break;
2467                 case AF_INET6:
2468                         af = 2;
2469                         break;
2470                 default:
2471                         af = 0;
2472                         break;
2473                 }
2474                 if (af) {
2475                         union sockunion tmp;
2476
2477                         tmp = *su;
2478                         if (tmp.su_family == AF_INET6)
2479                                 tmp.su_sin6.sin6_scope_id = 0;
2480                         if (!getnameinfo((struct sockaddr *)&tmp, tmp.su_len,
2481                                         hname, sizeof(hname) - 1, NULL, 0,
2482                                         NI_NUMERICHOST)) {
2483                                 hname[sizeof(hname) - 1] = 0;
2484                                 printf("     %s |%d|%s|%d|\r\n",
2485                                         ispassive ? "EPSV" : "EPRT",
2486                                         af, hname, htons(tmp.su_port));
2487                         }
2488                 }
2489             }
2490 #undef UC
2491         } else
2492                 printf("     No data connection\r\n");
2493         reply(211, "End of status.");
2494 }
2495
2496 void
2497 fatalerror(char *s)
2498 {
2499
2500         reply(451, "Error in server: %s", s);
2501         reply(221, "Closing connection due to server error.");
2502         dologout(0);
2503         /* NOTREACHED */
2504 }
2505
2506 void
2507 reply(int n, const char *fmt, ...)
2508 {
2509         va_list ap;
2510
2511         (void)printf("%d ", n);
2512         va_start(ap, fmt);
2513         (void)vprintf(fmt, ap);
2514         va_end(ap);
2515         (void)printf("\r\n");
2516         (void)fflush(stdout);
2517         if (ftpdebug) {
2518                 syslog(LOG_DEBUG, "<--- %d ", n);
2519                 va_start(ap, fmt);
2520                 vsyslog(LOG_DEBUG, fmt, ap);
2521                 va_end(ap);
2522         }
2523 }
2524
2525 void
2526 lreply(int n, const char *fmt, ...)
2527 {
2528         va_list ap;
2529
2530         (void)printf("%d- ", n);
2531         va_start(ap, fmt);
2532         (void)vprintf(fmt, ap);
2533         va_end(ap);
2534         (void)printf("\r\n");
2535         (void)fflush(stdout);
2536         if (ftpdebug) {
2537                 syslog(LOG_DEBUG, "<--- %d- ", n);
2538                 va_start(ap, fmt);
2539                 vsyslog(LOG_DEBUG, fmt, ap);
2540                 va_end(ap);
2541         }
2542 }
2543
2544 static void
2545 ack(char *s)
2546 {
2547
2548         reply(250, "%s command successful.", s);
2549 }
2550
2551 void
2552 nack(char *s)
2553 {
2554
2555         reply(502, "%s command not implemented.", s);
2556 }
2557
2558 /* ARGSUSED */
2559 void
2560 yyerror(char *s)
2561 {
2562         char *cp;
2563
2564         if ((cp = strchr(cbuf,'\n')))
2565                 *cp = '\0';
2566         reply(500, "%s: command not understood.", cbuf);
2567 }
2568
2569 void
2570 delete(char *name)
2571 {
2572         struct stat st;
2573
2574         LOGCMD("delete", name);
2575         if (lstat(name, &st) < 0) {
2576                 perror_reply(550, name);
2577                 return;
2578         }
2579         if (S_ISDIR(st.st_mode)) {
2580                 if (rmdir(name) < 0) {
2581                         perror_reply(550, name);
2582                         return;
2583                 }
2584                 goto done;
2585         }
2586         if (guest && noguestmod) {
2587                 reply(550, "Operation not permitted.");
2588                 return;
2589         }
2590         if (unlink(name) < 0) {
2591                 perror_reply(550, name);
2592                 return;
2593         }
2594 done:
2595         ack("DELE");
2596 }
2597
2598 void
2599 cwd(char *path)
2600 {
2601
2602         if (chdir(path) < 0)
2603                 perror_reply(550, path);
2604         else
2605                 ack("CWD");
2606 }
2607
2608 void
2609 makedir(char *name)
2610 {
2611         char *s;
2612
2613         LOGCMD("mkdir", name);
2614         if (guest && noguestmkd)
2615                 reply(550, "Operation not permitted.");
2616         else if (mkdir(name, 0777) < 0)
2617                 perror_reply(550, name);
2618         else {
2619                 if ((s = doublequote(name)) == NULL)
2620                         fatalerror("Ran out of memory.");
2621                 reply(257, "\"%s\" directory created.", s);
2622                 free(s);
2623         }
2624 }
2625
2626 void
2627 removedir(char *name)
2628 {
2629
2630         LOGCMD("rmdir", name);
2631         if (rmdir(name) < 0)
2632                 perror_reply(550, name);
2633         else
2634                 ack("RMD");
2635 }
2636
2637 void
2638 pwd(void)
2639 {
2640         char *s, path[MAXPATHLEN + 1];
2641
2642         if (getcwd(path, sizeof(path)) == NULL)
2643                 perror_reply(550, "Get current directory");
2644         else {
2645                 if ((s = doublequote(path)) == NULL)
2646                         fatalerror("Ran out of memory.");
2647                 reply(257, "\"%s\" is current directory.", s);
2648                 free(s);
2649         }
2650 }
2651
2652 char *
2653 renamefrom(char *name)
2654 {
2655         struct stat st;
2656
2657         if (guest && noguestmod) {
2658                 reply(550, "Operation not permitted.");
2659                 return (NULL);
2660         }
2661         if (lstat(name, &st) < 0) {
2662                 perror_reply(550, name);
2663                 return (NULL);
2664         }
2665         reply(350, "File exists, ready for destination name.");
2666         return (name);
2667 }
2668
2669 void
2670 renamecmd(char *from, char *to)
2671 {
2672         struct stat st;
2673
2674         LOGCMD2("rename", from, to);
2675
2676         if (guest && (stat(to, &st) == 0)) {
2677                 reply(550, "%s: permission denied.", to);
2678                 return;
2679         }
2680
2681         if (rename(from, to) < 0)
2682                 perror_reply(550, "rename");
2683         else
2684                 ack("RNTO");
2685 }
2686
2687 static void
2688 dolog(struct sockaddr *who)
2689 {
2690         char who_name[NI_MAXHOST];
2691
2692         realhostname_sa(remotehost, sizeof(remotehost) - 1, who, who->sa_len);
2693         remotehost[sizeof(remotehost) - 1] = 0;
2694         if (getnameinfo(who, who->sa_len,
2695                 who_name, sizeof(who_name) - 1, NULL, 0, NI_NUMERICHOST))
2696                         *who_name = 0;
2697         who_name[sizeof(who_name) - 1] = 0;
2698
2699 #ifdef SETPROCTITLE
2700 #ifdef VIRTUAL_HOSTING
2701         if (thishost != firsthost)
2702                 snprintf(proctitle, sizeof(proctitle), "%s: connected (to %s)",
2703                          remotehost, hostname);
2704         else
2705 #endif
2706                 snprintf(proctitle, sizeof(proctitle), "%s: connected",
2707                          remotehost);
2708         setproctitle("%s", proctitle);
2709 #endif /* SETPROCTITLE */
2710
2711         if (logging) {
2712 #ifdef VIRTUAL_HOSTING
2713                 if (thishost != firsthost)
2714                         syslog(LOG_INFO, "connection from %s (%s) to %s",
2715                                remotehost, who_name, hostname);
2716                 else
2717 #endif
2718                         syslog(LOG_INFO, "connection from %s (%s)",
2719                                remotehost, who_name);
2720         }
2721 }
2722
2723 /*
2724  * Record logout in wtmp file
2725  * and exit with supplied status.
2726  */
2727 void
2728 dologout(int status)
2729 {
2730
2731         if (logged_in && dowtmp) {
2732                 (void) seteuid(0);
2733                 ftpd_logwtmp(ttyline, "", NULL);
2734         }
2735         /* beware of flushing buffers after a SIGPIPE */
2736         _exit(status);
2737 }
2738
2739 static void
2740 sigurg(int signo)
2741 {
2742
2743         recvurg = 1;
2744 }
2745
2746 static void
2747 maskurg(int flag)
2748 {
2749         int oerrno;
2750         sigset_t sset;
2751
2752         if (!transflag) {
2753                 syslog(LOG_ERR, "Internal: maskurg() while no transfer");
2754                 return;
2755         }
2756         oerrno = errno;
2757         sigemptyset(&sset);
2758         sigaddset(&sset, SIGURG);
2759         sigprocmask(flag ? SIG_BLOCK : SIG_UNBLOCK, &sset, NULL);
2760         errno = oerrno;
2761 }
2762
2763 static void
2764 flagxfer(int flag)
2765 {
2766
2767         if (flag) {
2768                 if (transflag)
2769                         syslog(LOG_ERR, "Internal: flagxfer(1): "
2770                                         "transfer already under way");
2771                 transflag = 1;
2772                 maskurg(0);
2773                 recvurg = 0;
2774         } else {
2775                 if (!transflag)
2776                         syslog(LOG_ERR, "Internal: flagxfer(0): "
2777                                         "no active transfer");
2778                 maskurg(1);
2779                 transflag = 0;
2780         }
2781 }
2782
2783 /*
2784  * Returns 0 if OK to resume or -1 if abort requested.
2785  */
2786 static int
2787 myoob(void)
2788 {
2789         char *cp;
2790
2791         if (!transflag) {
2792                 syslog(LOG_ERR, "Internal: myoob() while no transfer");
2793                 return (0);
2794         }
2795         cp = tmpline;
2796         if (getline(cp, 7, stdin) == NULL) {
2797                 reply(221, "You could at least say goodbye.");
2798                 dologout(0);
2799         }
2800         upper(cp);
2801         if (strcmp(cp, "ABOR\r\n") == 0) {
2802                 tmpline[0] = '\0';
2803                 reply(426, "Transfer aborted. Data connection closed.");
2804                 reply(226, "Abort successful.");
2805                 return (-1);
2806         }
2807         if (strcmp(cp, "STAT\r\n") == 0) {
2808                 tmpline[0] = '\0';
2809                 if (file_size != -1)
2810                         reply(213, "Status: %jd of %jd bytes transferred.",
2811                                    (intmax_t)byte_count, (intmax_t)file_size);
2812                 else
2813                         reply(213, "Status: %jd bytes transferred.",
2814                                    (intmax_t)byte_count);
2815         }
2816         return (0);
2817 }
2818
2819 /*
2820  * Note: a response of 425 is not mentioned as a possible response to
2821  *      the PASV command in RFC959. However, it has been blessed as
2822  *      a legitimate response by Jon Postel in a telephone conversation
2823  *      with Rick Adams on 25 Jan 89.
2824  */
2825 void
2826 passive(void)
2827 {
2828         socklen_t len;
2829         int on;
2830         char *p, *a;
2831
2832         if (pdata >= 0)         /* close old port if one set */
2833                 close(pdata);
2834
2835         pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2836         if (pdata < 0) {
2837                 perror_reply(425, "Can't open passive connection");
2838                 return;
2839         }
2840         on = 1;
2841         if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2842                 syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2843
2844         (void) seteuid(0);
2845
2846 #ifdef IP_PORTRANGE
2847         if (ctrl_addr.su_family == AF_INET) {
2848             on = restricted_data_ports ? IP_PORTRANGE_HIGH
2849                                        : IP_PORTRANGE_DEFAULT;
2850
2851             if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2852                             &on, sizeof(on)) < 0)
2853                     goto pasv_error;
2854         }
2855 #endif
2856 #ifdef IPV6_PORTRANGE
2857         if (ctrl_addr.su_family == AF_INET6) {
2858             on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2859                                        : IPV6_PORTRANGE_DEFAULT;
2860
2861             if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2862                             &on, sizeof(on)) < 0)
2863                     goto pasv_error;
2864         }
2865 #endif
2866
2867         pasv_addr = ctrl_addr;
2868         pasv_addr.su_port = 0;
2869         if (bind(pdata, (struct sockaddr *)&pasv_addr, pasv_addr.su_len) < 0)
2870                 goto pasv_error;
2871
2872         (void) seteuid(pw->pw_uid);
2873
2874         len = sizeof(pasv_addr);
2875         if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2876                 goto pasv_error;
2877         if (listen(pdata, 1) < 0)
2878                 goto pasv_error;
2879         if (pasv_addr.su_family == AF_INET)
2880                 a = (char *) &pasv_addr.su_sin.sin_addr;
2881         else if (pasv_addr.su_family == AF_INET6 &&
2882                  IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr))
2883                 a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
2884         else
2885                 goto pasv_error;
2886
2887         p = (char *) &pasv_addr.su_port;
2888
2889 #define UC(b) (((int) b) & 0xff)
2890
2891         reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
2892                 UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
2893         return;
2894
2895 pasv_error:
2896         (void) seteuid(pw->pw_uid);
2897         (void) close(pdata);
2898         pdata = -1;
2899         perror_reply(425, "Can't open passive connection");
2900         return;
2901 }
2902
2903 /*
2904  * Long Passive defined in RFC 1639.
2905  *     228 Entering Long Passive Mode
2906  *         (af, hal, h1, h2, h3,..., pal, p1, p2...)
2907  */
2908
2909 void
2910 long_passive(char *cmd, int pf)
2911 {
2912         socklen_t len;
2913         int on;
2914         char *p, *a;
2915
2916         if (pdata >= 0)         /* close old port if one set */
2917                 close(pdata);
2918
2919         if (pf != PF_UNSPEC) {
2920                 if (ctrl_addr.su_family != pf) {
2921                         switch (ctrl_addr.su_family) {
2922                         case AF_INET:
2923                                 pf = 1;
2924                                 break;
2925                         case AF_INET6:
2926                                 pf = 2;
2927                                 break;
2928                         default:
2929                                 pf = 0;
2930                                 break;
2931                         }
2932                         /*
2933                          * XXX
2934                          * only EPRT/EPSV ready clients will understand this
2935                          */
2936                         if (strcmp(cmd, "EPSV") == 0 && pf) {
2937                                 reply(522, "Network protocol mismatch, "
2938                                         "use (%d)", pf);
2939                         } else
2940                                 reply(501, "Network protocol mismatch."); /*XXX*/
2941
2942                         return;
2943                 }
2944         }
2945
2946         pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2947         if (pdata < 0) {
2948                 perror_reply(425, "Can't open passive connection");
2949                 return;
2950         }
2951         on = 1;
2952         if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2953                 syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2954
2955         (void) seteuid(0);
2956
2957         pasv_addr = ctrl_addr;
2958         pasv_addr.su_port = 0;
2959         len = pasv_addr.su_len;
2960
2961 #ifdef IP_PORTRANGE
2962         if (ctrl_addr.su_family == AF_INET) {
2963             on = restricted_data_ports ? IP_PORTRANGE_HIGH
2964                                        : IP_PORTRANGE_DEFAULT;
2965
2966             if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2967                             &on, sizeof(on)) < 0)
2968                     goto pasv_error;
2969         }
2970 #endif
2971 #ifdef IPV6_PORTRANGE
2972         if (ctrl_addr.su_family == AF_INET6) {
2973             on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2974                                        : IPV6_PORTRANGE_DEFAULT;
2975
2976             if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2977                             &on, sizeof(on)) < 0)
2978                     goto pasv_error;
2979         }
2980 #endif
2981
2982         if (bind(pdata, (struct sockaddr *)&pasv_addr, len) < 0)
2983                 goto pasv_error;
2984
2985         (void) seteuid(pw->pw_uid);
2986
2987         if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2988                 goto pasv_error;
2989         if (listen(pdata, 1) < 0)
2990                 goto pasv_error;
2991
2992 #define UC(b) (((int) b) & 0xff)
2993
2994         if (strcmp(cmd, "LPSV") == 0) {
2995                 p = (char *)&pasv_addr.su_port;
2996                 switch (pasv_addr.su_family) {
2997                 case AF_INET:
2998                         a = (char *) &pasv_addr.su_sin.sin_addr;
2999                 v4_reply:
3000                         reply(228,
3001 "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3002                               4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3003                               2, UC(p[0]), UC(p[1]));
3004                         return;
3005                 case AF_INET6:
3006                         if (IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr)) {
3007                                 a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
3008                                 goto v4_reply;
3009                         }
3010                         a = (char *) &pasv_addr.su_sin6.sin6_addr;
3011                         reply(228,
3012 "Entering Long Passive Mode "
3013 "(%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3014                               6, 16, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3015                               UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
3016                               UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
3017                               UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
3018                               2, UC(p[0]), UC(p[1]));
3019                         return;
3020                 }
3021         } else if (strcmp(cmd, "EPSV") == 0) {
3022                 switch (pasv_addr.su_family) {
3023                 case AF_INET:
3024                 case AF_INET6:
3025                         reply(229, "Entering Extended Passive Mode (|||%d|)",
3026                                 ntohs(pasv_addr.su_port));
3027                         return;
3028                 }
3029         } else {
3030                 /* more proper error code? */
3031         }
3032
3033 pasv_error:
3034         (void) seteuid(pw->pw_uid);
3035         (void) close(pdata);
3036         pdata = -1;
3037         perror_reply(425, "Can't open passive connection");
3038         return;
3039 }
3040
3041 /*
3042  * Generate unique name for file with basename "local"
3043  * and open the file in order to avoid possible races.
3044  * Try "local" first, then "local.1", "local.2" etc, up to "local.99".
3045  * Return descriptor to the file, set "name" to its name.
3046  *
3047  * Generates failure reply on error.
3048  */
3049 static int
3050 guniquefd(char *local, char **name)
3051 {
3052         static char new[MAXPATHLEN];
3053         struct stat st;
3054         char *cp;
3055         int count;
3056         int fd;
3057
3058         cp = strrchr(local, '/');
3059         if (cp)
3060                 *cp = '\0';
3061         if (stat(cp ? local : ".", &st) < 0) {
3062                 perror_reply(553, cp ? local : ".");
3063                 return (-1);
3064         }
3065         if (cp) {
3066                 /*
3067                  * Let not overwrite dirname with counter suffix.
3068                  * -4 is for /nn\0
3069                  * In this extreme case dot won't be put in front of suffix.
3070                  */
3071                 if (strlen(local) > sizeof(new) - 4) {
3072                         reply(553, "Pathname too long.");
3073                         return (-1);
3074                 }
3075                 *cp = '/';
3076         }
3077         /* -4 is for the .nn<null> we put on the end below */
3078         (void) snprintf(new, sizeof(new) - 4, "%s", local);
3079         cp = new + strlen(new);
3080         /*
3081          * Don't generate dotfile unless requested explicitly.
3082          * This covers the case when basename gets truncated off
3083          * by buffer size.
3084          */
3085         if (cp > new && cp[-1] != '/')
3086                 *cp++ = '.';
3087         for (count = 0; count < 100; count++) {
3088                 /* At count 0 try unmodified name */
3089                 if (count)
3090                         (void)sprintf(cp, "%d", count);
3091                 if ((fd = open(count ? new : local,
3092                     O_RDWR | O_CREAT | O_EXCL, 0666)) >= 0) {
3093                         *name = count ? new : local;
3094                         return (fd);
3095                 }
3096                 if (errno != EEXIST) {
3097                         perror_reply(553, count ? new : local);
3098                         return (-1);
3099                 }
3100         }
3101         reply(452, "Unique file name cannot be created.");
3102         return (-1);
3103 }
3104
3105 /*
3106  * Format and send reply containing system error number.
3107  */
3108 void
3109 perror_reply(int code, char *string)
3110 {
3111
3112         reply(code, "%s: %s.", string, strerror(errno));
3113 }
3114
3115 static char *onefile[] = {
3116         "",
3117         0
3118 };
3119
3120 void
3121 send_file_list(char *whichf)
3122 {
3123         struct stat st;
3124         DIR *dirp = NULL;
3125         struct dirent *dir;
3126         FILE *dout = NULL;
3127         char **dirlist, *dirname;
3128         int simple = 0;
3129         int freeglob = 0;
3130         glob_t gl;
3131
3132         if (strpbrk(whichf, "~{[*?") != NULL) {
3133                 int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
3134
3135                 memset(&gl, 0, sizeof(gl));
3136                 gl.gl_matchc = MAXGLOBARGS;
3137                 flags |= GLOB_LIMIT;
3138                 freeglob = 1;
3139                 if (glob(whichf, flags, 0, &gl)) {
3140                         reply(550, "No matching files found.");
3141                         goto out;
3142                 } else if (gl.gl_pathc == 0) {
3143                         errno = ENOENT;
3144                         perror_reply(550, whichf);
3145                         goto out;
3146                 }
3147                 dirlist = gl.gl_pathv;
3148         } else {
3149                 onefile[0] = whichf;
3150                 dirlist = onefile;
3151                 simple = 1;
3152         }
3153
3154         while ((dirname = *dirlist++)) {
3155                 if (stat(dirname, &st) < 0) {
3156                         /*
3157                          * If user typed "ls -l", etc, and the client
3158                          * used NLST, do what the user meant.
3159                          */
3160                         if (dirname[0] == '-' && *dirlist == NULL &&
3161                             dout == NULL)
3162                                 retrieve(_PATH_LS " %s", dirname);
3163                         else
3164                                 perror_reply(550, whichf);
3165                         goto out;
3166                 }
3167
3168                 if (S_ISREG(st.st_mode)) {
3169                         if (dout == NULL) {
3170                                 dout = dataconn("file list", -1, "w");
3171                                 if (dout == NULL)
3172                                         goto out;
3173                                 STARTXFER;
3174                         }
3175                         START_UNSAFE;
3176                         fprintf(dout, "%s%s\n", dirname,
3177                                 type == TYPE_A ? "\r" : "");
3178                         END_UNSAFE;
3179                         if (ferror(dout))
3180                                 goto data_err;
3181                         byte_count += strlen(dirname) +
3182                                       (type == TYPE_A ? 2 : 1);
3183                         CHECKOOB(goto abrt);
3184                         continue;
3185                 } else if (!S_ISDIR(st.st_mode))
3186                         continue;
3187
3188                 if ((dirp = opendir(dirname)) == NULL)
3189                         continue;
3190
3191                 while ((dir = readdir(dirp)) != NULL) {
3192                         char nbuf[MAXPATHLEN];
3193
3194                         CHECKOOB(goto abrt);
3195
3196                         if (dir->d_name[0] == '.' && dir->d_namlen == 1)
3197                                 continue;
3198                         if (dir->d_name[0] == '.' && dir->d_name[1] == '.' &&
3199                             dir->d_namlen == 2)
3200                                 continue;
3201
3202                         snprintf(nbuf, sizeof(nbuf),
3203                                 "%s/%s", dirname, dir->d_name);
3204
3205                         /*
3206                          * We have to do a stat to insure it's
3207                          * not a directory or special file.
3208                          */
3209                         if (simple || (stat(nbuf, &st) == 0 &&
3210                             S_ISREG(st.st_mode))) {
3211                                 if (dout == NULL) {
3212                                         dout = dataconn("file list", -1, "w");
3213                                         if (dout == NULL)
3214                                                 goto out;
3215                                         STARTXFER;
3216                                 }
3217                                 START_UNSAFE;
3218                                 if (nbuf[0] == '.' && nbuf[1] == '/')
3219                                         fprintf(dout, "%s%s\n", &nbuf[2],
3220                                                 type == TYPE_A ? "\r" : "");
3221                                 else
3222                                         fprintf(dout, "%s%s\n", nbuf,
3223                                                 type == TYPE_A ? "\r" : "");
3224                                 END_UNSAFE;
3225                                 if (ferror(dout))
3226                                         goto data_err;
3227                                 byte_count += strlen(nbuf) +
3228                                               (type == TYPE_A ? 2 : 1);
3229                                 CHECKOOB(goto abrt);
3230                         }
3231                 }
3232                 (void) closedir(dirp);
3233                 dirp = NULL;
3234         }
3235
3236         if (dout == NULL)
3237                 reply(550, "No files found.");
3238         else if (ferror(dout))
3239 data_err:       perror_reply(550, "Data connection");
3240         else
3241                 reply(226, "Transfer complete.");
3242 out:
3243         if (dout) {
3244                 ENDXFER;
3245 abrt:
3246                 (void) fclose(dout);
3247                 data = -1;
3248                 pdata = -1;
3249         }
3250         if (dirp)
3251                 (void) closedir(dirp);
3252         if (freeglob) {
3253                 freeglob = 0;
3254                 globfree(&gl);
3255         }
3256 }
3257
3258 void
3259 reapchild(int signo)
3260 {
3261         while (waitpid(-1, NULL, WNOHANG) > 0);
3262 }
3263
3264 #ifdef OLD_SETPROCTITLE
3265 /*
3266  * Clobber argv so ps will show what we're doing.  (Stolen from sendmail.)
3267  * Warning, since this is usually started from inetd.conf, it often doesn't
3268  * have much of an environment or arglist to overwrite.
3269  */
3270 void
3271 setproctitle(const char *fmt, ...)
3272 {
3273         int i;
3274         va_list ap;
3275         char *p, *bp, ch;
3276         char buf[LINE_MAX];
3277
3278         va_start(ap, fmt);
3279         (void)vsnprintf(buf, sizeof(buf), fmt, ap);
3280
3281         /* make ps print our process name */
3282         p = Argv[0];
3283         *p++ = '-';
3284
3285         i = strlen(buf);
3286         if (i > LastArgv - p - 2) {
3287                 i = LastArgv - p - 2;
3288                 buf[i] = '\0';
3289         }
3290         bp = buf;
3291         while (ch = *bp++)
3292                 if (ch != '\n' && ch != '\r')
3293                         *p++ = ch;
3294         while (p < LastArgv)
3295                 *p++ = ' ';
3296 }
3297 #endif /* OLD_SETPROCTITLE */
3298
3299 static void
3300 appendf(char **strp, char *fmt, ...)
3301 {
3302         va_list ap;
3303         char *ostr, *p;
3304
3305         va_start(ap, fmt);
3306         vasprintf(&p, fmt, ap);
3307         va_end(ap);
3308         if (p == NULL)
3309                 fatalerror("Ran out of memory.");
3310         if (*strp == NULL)
3311                 *strp = p;
3312         else {
3313                 ostr = *strp;
3314                 asprintf(strp, "%s%s", ostr, p);
3315                 if (*strp == NULL)
3316                         fatalerror("Ran out of memory.");
3317                 free(ostr);
3318         }
3319 }
3320
3321 static void
3322 logcmd(char *cmd, char *file1, char *file2, off_t cnt)
3323 {
3324         char *msg = NULL;
3325         char wd[MAXPATHLEN + 1];
3326
3327         if (logging <= 1)
3328                 return;
3329
3330         if (getcwd(wd, sizeof(wd) - 1) == NULL)
3331                 strcpy(wd, strerror(errno));
3332
3333         appendf(&msg, "%s", cmd);
3334         if (file1)
3335                 appendf(&msg, " %s", file1);
3336         if (file2)
3337                 appendf(&msg, " %s", file2);
3338         if (cnt >= 0)
3339                 appendf(&msg, " = %jd bytes", (intmax_t)cnt);
3340         appendf(&msg, " (wd: %s", wd);
3341         if (guest || dochroot)
3342                 appendf(&msg, "; chrooted");
3343         appendf(&msg, ")");
3344         syslog(LOG_INFO, "%s", msg);
3345         free(msg);
3346 }
3347
3348 static void
3349 logxfer(char *name, off_t size, time_t start)
3350 {
3351         char buf[MAXPATHLEN + 1024];
3352         char path[MAXPATHLEN + 1];
3353         time_t now;
3354
3355         if (statfd >= 0) {
3356                 time(&now);
3357                 if (realpath(name, path) == NULL) {
3358                         syslog(LOG_NOTICE, "realpath failed on %s: %m", path);
3359                         return;
3360                 }
3361                 snprintf(buf, sizeof(buf), "%.20s!%s!%s!%s!%jd!%ld\n",
3362                         ctime(&now)+4, ident, remotehost,
3363                         path, (intmax_t)size,
3364                         (long)(now - start + (now == start)));
3365                 write(statfd, buf, strlen(buf));
3366         }
3367 }
3368
3369 static char *
3370 doublequote(char *s)
3371 {
3372         int n;
3373         char *p, *s2;
3374
3375         for (p = s, n = 0; *p; p++)
3376                 if (*p == '"')
3377                         n++;
3378
3379         if ((s2 = malloc(p - s + n + 1)) == NULL)
3380                 return (NULL);
3381
3382         for (p = s2; *s; s++, p++) {
3383                 if ((*p = *s) == '"')
3384                         *(++p) = '"';
3385         }
3386         *p = '\0';
3387
3388         return (s2);
3389 }
3390
3391 /* setup server socket for specified address family */
3392 /* if af is PF_UNSPEC more than one socket may be returned */
3393 /* the returned list is dynamically allocated, so caller needs to free it */
3394 static int *
3395 socksetup(int af, char *bindname, const char *bindport)
3396 {
3397         struct addrinfo hints, *res, *r;
3398         int error, maxs, *s, *socks;
3399         const int on = 1;
3400
3401         memset(&hints, 0, sizeof(hints));
3402         hints.ai_flags = AI_PASSIVE;
3403         hints.ai_family = af;
3404         hints.ai_socktype = SOCK_STREAM;
3405         error = getaddrinfo(bindname, bindport, &hints, &res);
3406         if (error) {
3407                 syslog(LOG_ERR, "%s", gai_strerror(error));
3408                 if (error == EAI_SYSTEM)
3409                         syslog(LOG_ERR, "%s", strerror(errno));
3410                 return NULL;
3411         }
3412
3413         /* Count max number of sockets we may open */
3414         for (maxs = 0, r = res; r; r = r->ai_next, maxs++)
3415                 ;
3416         socks = malloc((maxs + 1) * sizeof(int));
3417         if (!socks) {
3418                 freeaddrinfo(res);
3419                 syslog(LOG_ERR, "couldn't allocate memory for sockets");
3420                 return NULL;
3421         }
3422
3423         *socks = 0;   /* num of sockets counter at start of array */
3424         s = socks + 1;
3425         for (r = res; r; r = r->ai_next) {
3426                 *s = socket(r->ai_family, r->ai_socktype, r->ai_protocol);
3427                 if (*s < 0) {
3428                         syslog(LOG_DEBUG, "control socket: %m");
3429                         continue;
3430                 }
3431                 if (setsockopt(*s, SOL_SOCKET, SO_REUSEADDR,
3432                     &on, sizeof(on)) < 0)
3433                         syslog(LOG_WARNING,
3434                             "control setsockopt (SO_REUSEADDR): %m");
3435                 if (r->ai_family == AF_INET6) {
3436                         if (setsockopt(*s, IPPROTO_IPV6, IPV6_V6ONLY,
3437                             &on, sizeof(on)) < 0)
3438                                 syslog(LOG_WARNING,
3439                                     "control setsockopt (IPV6_V6ONLY): %m");
3440                 }
3441                 if (bind(*s, r->ai_addr, r->ai_addrlen) < 0) {
3442                         syslog(LOG_DEBUG, "control bind: %m");
3443                         close(*s);
3444                         continue;
3445                 }
3446                 (*socks)++;
3447                 s++;
3448         }
3449
3450         if (res)
3451                 freeaddrinfo(res);
3452
3453         if (*socks == 0) {
3454                 syslog(LOG_ERR, "control socket: Couldn't bind to any socket");
3455                 free(socks);
3456                 return NULL;
3457         }
3458         return(socks);
3459 }