/*
  Copyright (C) 1995-2023 Free Software Foundation, Inc.

  This file is part of GNU Inetutils.

  GNU Inetutils is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or (at
  your option) any later version.

  GNU Inetutils is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program.  If not, see `http://www.gnu.org/licenses/'. */

/*
 * Copyright (c) 1983, 1990, 1992, 1993, 2002
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <config.h>

#include <sys/param.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <time.h>

#include <sys/socket.h>
#include <sys/wait.h>
#include <netinet/in.h>
#ifdef HAVE_NETINET_IN_SYSTM_H
# include <netinet/in_systm.h>
#endif
#ifdef HAVE_NETINET_IP_H
# include <netinet/ip.h>
#endif

#include <ctype.h>
#include <dirent.h>
#include <error.h>
#include <errno.h>
#include <fcntl.h>
#include <netdb.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <stdint.h>		/* intmax_t */
#include <string.h>
#include <string.h>
#include <unistd.h>
#ifndef HAVE_UTIMES
# include <utime.h>		/* If we don't have utimes(), use utime(). */
#endif
#include <progname.h>
#include <attribute.h>
#include <libinetutils.h>
#include <argp.h>
#include <error.h>
#include <xalloc.h>

typedef struct
{
  int cnt;
  char *buf;
} BUF;

BUF *allocbuf (BUF *, int, int);
char *colon (char *);
void lostconn (int);
void nospace (void);
int okname (char *);
void run_err (const char *, ...);
int susystem (char *, int);
void verifydir (char *);

#ifdef SHISHI
# include <shishi.h>
# include "shishi_def.h"
#endif /* SHISHI */

#ifdef KERBEROS
# ifdef HAVE_KERBEROSIV_DES_H
#  include <kerberosIV/des.h>
# endif
# ifdef HAVE_KERBEROSIV_KRB_H
#  include <kerberosIV/krb.h>
# endif
#endif /* KERBEROS */

#if defined KERBEROS || defined SHISHI
const char *dest_realm = NULL;
int use_kerberos = 1;
int doencrypt = 0;

# ifdef KERBEROS
CREDENTIALS cred;
Key_schedule schedule;
extern char *krb_realmofhost ();

# elif defined SHISHI		/* !KERBEROS  */
Shishi *h;
Shishi_key *enckey;
shishi_ivector iv1, iv2, iv3, iv4;
shishi_ivector *ivtab[4];

int keytype;
int keylen;
int rc;
int wlen;
# endif/* SHISHI */
#endif /* KERBEROS || SHISHI */

const char doc[] =
  "Remote copy SOURCE to DEST, or multiple SOURCE(s) to DIRECTORY.";
const char arg_doc[] =
  "SOURCE DEST\n" "SOURCE... DIRECTORY\n"
  "--target-directory=DIRECTORY SOURCE...";

char *target = NULL;
int preserve_option;
int from_option, to_option;
int iamremote, iamrecursive, targetshouldbedirectory;
#if defined WITH_ORCMD_AF || defined WITH_RCMD_AF || defined SHISHI
sa_family_t family = AF_UNSPEC;
#endif

static struct argp_option options[] = {
#define GRID 0
  {"recursive", 'r', NULL, 0,
   "if any of the source files are directories, copies"
   " each subtree rooted at that name; in this case the"
   " destination must be a directory",
   GRID + 1},
  {"preserve", 'p', NULL, 0,
   "attempt to preserve (duplicate) in its copies the"
   " modification times and modes of the source files",
   GRID + 1},
  {"target-directory", 'd', "DIRECTORY", OPTION_ARG_OPTIONAL,
   "copy all SOURCE arguments into DIRECTORY",
   GRID + 1},
  {"from", 'f', NULL, 0,
   "copying from remote host (server use only)",
   GRID + 1},
  {"to", 't', NULL, 0,
   "copying to remote host (server use only)",
   GRID + 1},
#if defined WITH_ORCMD_AF || defined WITH_RCMD_AF || defined SHISHI
  {"ipv4", '4', NULL, 0,
   "use only IPv4",
   GRID + 1},
  {"ipv6", '6', NULL, 0,
   "use only IPv6",
   GRID + 1},
#endif /* WITH_ORCMD_AF || WITH_RCMD_AF || SHISHI */
#undef GRID
#if defined KERBEROS || defined SHISHI
# define GRID 10
  {"kerberos", 'K', NULL, 0,
   "turns off all Kerberos authentication",
   GRID + 1},
  {"realm", 'k', "REALM", 0,
   "obtain tickets for a remote host in REALM instead of the remote host's realm",
   GRID + 1},
# ifdef ENCRYPTION
  {"encrypt", 'x', NULL, 0,
   "encrypt all data transfer",
   GRID + 1},
# endif
# undef GRID
#endif
  {NULL, 0, NULL, 0, NULL, 0}
};

static error_t
parse_opt (int key, char *arg, struct argp_state *state MAYBE_UNUSED)
{
  switch (key)
    {
#if defined WITH_ORCMD_AF || defined WITH_RCMD_AF || defined SHISHI
    case '4':
      family = AF_INET;
      break;
    case '6':
      family = AF_INET6;
      break;
#endif /* WITH_ORCMD_AF || WITH_RCMD_AF || SHISHI */

#if defined KERBEROS || defined SHISHI
    case 'K':
      use_kerberos = 0;
      break;

    case 'k':
      dest_realm = arg;
      break;

# ifdef ENCRYPTION
    case 'x':
      doencrypt = 1;
#  ifdef KERBEROS
      des_set_key (cred.session, schedule);
#  endif
      break;
# endif/* ENCRYPTION */
#endif /* KERBEROS || SHISHI */

    case 'p':
      preserve_option = 1;
      break;

    case 'r':
      iamrecursive = 1;
      break;

      /* Server options. */
    case 'd':
      targetshouldbedirectory = 1;
      if (arg && strlen (arg))
	target = xstrdup (arg);	/* Client side use.  */
      break;

    case 'f':			/* "from" */
      iamremote = 1;
      from_option = 1;
      break;

    case 't':			/* "to" */
      iamremote = 1;
      to_option = 1;
      break;

    default:
      return ARGP_ERR_UNKNOWN;
    }

  return 0;
}

static struct argp argp = {
  options,
  parse_opt,
  arg_doc,
  doc,
  NULL,
  NULL,
  NULL
};

struct passwd *pwd;
unsigned short port;
uid_t userid, effuid;
int errs, rem;

char *command;

#if defined KERBEROS || defined SHISHI
int kerberos (char **, char *, char *, char *);
void oldw (const char *, ...);
#endif /* KERBEROS || SHISHI */

int response (void);
void rsource (char *, struct stat *);
void sink (int, char *[]);
void source (int, char *[]);
void tolocal (int, char *[]);
void toremote (char *, int, char *[]);

int
main (int argc, char *argv[])
{
  struct servent *sp;
  char *targ;
  const char *shell;
  int index, rc;

  set_program_name (argv[0]);

  from_option = to_option = 0;
  iu_argp_init ("rcp", default_program_authors);
  argp_parse (&argp, argc, argv, 0, &index, NULL);
  argc -= index;
  argv += index;

#if defined KERBEROS || defined SHISHI
  if (use_kerberos)
    {
# if defined ENCRYPTION && defined KERBEROS
      shell = doencrypt ? "ekshell" : "kshell";
# else/* SHISHI */
      shell = "kshell";		/* Libshishi uses a single service.  */
# endif

      sp = getservbyname (shell, "tcp");
      if (sp == NULL)
	{
	  use_kerberos = 0;
	  oldw ("can't get entry for %s/tcp service", shell);
	  sp = getservbyname (shell = "shell", "tcp");
	}
    }
  else
    sp = getservbyname (shell = "shell", "tcp");
#else /* !KERBEROS && !SHISHI */
  sp = getservbyname (shell = "shell", "tcp");
#endif
  if (sp == NULL)
    error (EXIT_FAILURE, 0, "%s/tcp: unknown service", shell);
  port = sp->s_port;

  effuid = geteuid ();
  userid = getuid ();
  pwd = getpwuid (userid);
  if (pwd == NULL)
    error (EXIT_FAILURE, 0, "unknown user %d", (int) userid);

  rem = STDIN_FILENO;		/* XXX */

  if (from_option)
    {				/* Follow "protocol", send data. */
      response ();

      if (setuid (userid) == -1)
	{
	  error (EXIT_FAILURE, 0,
		 "Could not drop privileges (setuid() failed)");
	}

      source (argc, argv);
      exit (errs);
    }

  if (to_option)
    {				/* Receive data. */
      if (setuid (userid) == -1)
	{
	  error (EXIT_FAILURE, 0,
		 "Could not drop privileges (setuid() failed)");
	}

      sink (argc, argv);
      exit (errs);
    }

  if (argc < 1 || (argc < 2 && !(target && strlen (target))))
    error (EXIT_FAILURE, 0, "not enough arguments");

  if (argc > 2)
    targetshouldbedirectory = 1;

#if defined KERBEROS || defined SHISHI
  if (doencrypt && !use_kerberos)
    error (EXIT_FAILURE, 0, "encryption must use Kerberos");
#endif

  /* Command to be executed on remote system using "rsh". */
  rc = asprintf (&command, "rcp%s%s%s",
		 iamrecursive ? " -r" : "", preserve_option ? " -p" : "",
		 targetshouldbedirectory ? " -d" : "");

  if (rc < 0)
    xalloc_die ();

  rem = -1;
  signal (SIGPIPE, lostconn);

  /* Without a specified target, the last argument
   * is extracted to serve as target.
   */
  if (!target || !strlen (target))
    {
      target = xstrdup (argv[argc - 1]);
      argc--;			/* Do not count target directory.  */
    }

  targ = colon (target);
  if (targ)			/* Dest is remote host. */
    toremote (targ, argc, argv);
  else
    {
      tolocal (argc, argv);	/* Dest is local host. */
      if (targetshouldbedirectory)
	verifydir (target);
    }
  exit (errs);
}

void
toremote (char *targ, int argc, char *argv[])
{
  int i, tos;
  char *bp, *host, *src, *suser, *thost, *tuser;
#if defined IP_TOS && defined IPPROTO_IP && defined IPTOS_THROUGHPUT
  struct sockaddr_storage ss;
  socklen_t sslen;
#endif

  *targ++ = 0;
  if (*targ == 0)
    targ = ".";

  thost = strchr (target, '@');
  if (thost)
    {
      /* user@host */
      *thost++ = 0;
      tuser = target;
      if (*tuser == '\0')
	tuser = NULL;
      else if (!okname (tuser))
	exit (EXIT_FAILURE);
    }
  else
    {
      thost = target;
      tuser = NULL;
    }

  for (i = 0; i < argc; i++)
    {
      src = colon (argv[i]);
      if (src)
	{			/* remote to remote */
	  *src++ = 0;
	  if (*src == 0)
	    src = ".";
	  host = strchr (argv[i], '@');

	  if (host)
	    {
	      *host++ = 0;
	      suser = argv[i];
	      if (*suser == '\0')
		suser = pwd->pw_name;
	      else if (!okname (suser))
		continue;
	      if (asprintf (&bp,
#if defined ENCRYPTION && (defined KERBEROS || defined SHISHI)
			    "%s%s -l %s -n %s %s %s '%s%s%s:%s'",
#else
			    "%s -l %s -n %s %s %s '%s%s%s:%s'",
#endif
			    PATH_RSH,
#if ENCRYPTION && (defined KERBEROS || defined SHISHI)
			    doencrypt ? " -x" : "",
#endif
			    suser, host, command, src,
			    tuser ? tuser : "", tuser ? "@" : "",
			    thost, targ) < 0)
		xalloc_die ();
	    }
	  else
	    {
	      if (asprintf (&bp,
#if defined ENCRYPTION && (defined KERBEROS || defined SHISHI)
			    "exec %s%s -n %s %s %s '%s%s%s:%s'",
#else
			    "exec %s -n %s %s %s '%s%s%s:%s'",
#endif
			    PATH_RSH,
#if ENCRYPTION && (defined KERBEROS || defined SHISHI)
			    doencrypt ? " -x" : "",
#endif
			    argv[i], command, src,
			    tuser ? tuser : "", tuser ? "@" : "",
			    thost, targ) < 0)
		xalloc_die ();
	    }
	  susystem (bp, userid);
	  free (bp);
	}
      else
	{			/* local to remote */
	  if (rem == -1)
	    {
	      if (asprintf (&bp, "%s -t %s", command, targ) < 0)
		xalloc_die ();
	      host = thost;
#if defined KERBEROS || defined SHISHI
	      if (use_kerberos)
		rem = kerberos (&host, bp, pwd->pw_name,
				tuser ? tuser : pwd->pw_name);
	      else
#endif /* KERBEROS || SHISHI */
#ifdef WITH_ORCMD_AF
		rem = orcmd_af (&host, port, pwd->pw_name,
				tuser ? tuser : pwd->pw_name, bp, 0, family);
#elif defined WITH_RCMD_AF
		rem = rcmd_af (&host, port, pwd->pw_name,
			       tuser ? tuser : pwd->pw_name, bp, 0, family);
#elif defined WITH_ORCMD
		rem = orcmd (&host, port, pwd->pw_name,
			     tuser ? tuser : pwd->pw_name, bp, 0);
#else /* !WITH_ORCMD_AF && !WITH_RCMD_AF && !WITH_ORCMD */
		rem = rcmd (&host, port, pwd->pw_name,
			    tuser ? tuser : pwd->pw_name, bp, 0);
#endif
	      if (rem < 0)
		{
		  /* rcmd() provides its own error messages,
		   * but we add a vital addition, caused by
		   * insufficient capabilites.
		   */
		  if (errno == EACCES)
		    error (EXIT_FAILURE, 0, "No access to privileged ports.");

		  exit (EXIT_FAILURE);
		}
#if defined IP_TOS && defined IPPROTO_IP && defined IPTOS_THROUGHPUT
	      sslen = sizeof (ss);
	      (void) getpeername (rem, (struct sockaddr *) &ss, &sslen);
	      tos = IPTOS_THROUGHPUT;
	      if (ss.ss_family == AF_INET &&
		  setsockopt (rem, IPPROTO_IP, IP_TOS,
			      (char *) &tos, sizeof (int)) < 0)
		if (errno != ENOPROTOOPT)
		  error (0, errno, "TOS (ignored)");
#endif
	      if (response () < 0)
		exit (EXIT_FAILURE);
	      free (bp);

	      if (setuid (userid) == -1)
		{
		  error (EXIT_FAILURE, 0,
			 "Could not drop privileges (setuid() failed)");
		}
	    }
	  source (1, argv + i);
	  close (rem);
	  rem = -1;
#ifdef SHISHI
	  if (use_kerberos)
	    {
	      shishi_done (h);
# ifdef ENCRYPTION
	      if (doencrypt)
		{
		  shishi_key_done (enckey);
		  for (i = 0; i < 4; i++)
		    {
		      shishi_crypto_close (ivtab[i]->ctx);
		      free (ivtab[i]->iv);
		    }
		}
# endif/* ENCRYPTION */
	    }
#endif /* SHISHI */
	}
    }
}

void
tolocal (int argc, char *argv[])
{
  int i, tos;
  char *bp, *host, *src, *suser, *vect[1];
#if defined IP_TOS && defined IPPROTO_IP && defined IPTOS_THROUGHPUT
  struct sockaddr_storage ss;
  socklen_t sslen;
#endif

  for (i = 0; i < argc; i++)
    {
      src = colon (argv[i]);
      if (!src)
	{			/* Local to local. */
	  if (asprintf (&bp, "exec %s%s%s %s %s",
			PATH_CP,
			iamrecursive ? " -R" : "",
			preserve_option ? " -p" : "", argv[i], target) < 0)
	    xalloc_die ();
	  if (susystem (bp, userid))
	    ++errs;
	  free (bp);
	  continue;
	}
      *src++ = 0;
      if (*src == 0)
	src = ".";

      host = strchr (argv[i], '@');
      if (host == NULL)
	{
	  host = argv[i];
	  suser = pwd->pw_name;
	}
      else
	{
	  *host++ = 0;
	  suser = argv[i];
	  if (*suser == '\0')
	    suser = pwd->pw_name;
	  else if (!okname (suser))
	    continue;
	}
      if (asprintf (&bp, "%s -f %s", command, src) < 0)
	xalloc_die ();

#if defined KERBEROS || defined SHISHI
      if (use_kerberos)
	rem = kerberos (&host, bp, pwd->pw_name, suser);
      else
#elif defined WITH_ORCMD_AF
      rem = orcmd_af (&host, port, pwd->pw_name, suser, bp, 0, family);
#elif defined WITH_RCMD_AF
      rem = rcmd_af (&host, port, pwd->pw_name, suser, bp, 0, family);
#elif defined WITH_ORCMD
      rem = orcmd (&host, port, pwd->pw_name, suser, bp, 0);
#else /* !WITH_ORCMD_AF && !WITH_RCMD_AF && !WITH_ORCMD */
      rem = rcmd (&host, port, pwd->pw_name, suser, bp, 0);
#endif
      free (bp);
      if (rem < 0)
	{
	  ++errs;
	  continue;
	}

      if (seteuid (userid) == -1)
	{
	  error (EXIT_FAILURE, 0,
		 "Could not drop privileges (seteuid() failed)");
	}

#if defined IP_TOS && defined IPPROTO_IP && defined IPTOS_THROUGHPUT
      sslen = sizeof (ss);
      (void) getpeername (rem, (struct sockaddr *) &ss, &sslen);
      tos = IPTOS_THROUGHPUT;
      if (ss.ss_family == AF_INET &&
	  setsockopt (rem, IPPROTO_IP, IP_TOS,
		      (char *) &tos, sizeof (int)) < 0)
	if (errno != ENOPROTOOPT)
	  error (0, errno, "TOS (ignored)");
#endif
      vect[0] = target;
      sink (1, vect);

      if (seteuid (effuid) == -1)
	{
	  error (EXIT_FAILURE, 0,
		 "Could not drop privileges (seteuid() failed)");
	}

      close (rem);
      rem = -1;
#ifdef SHISHI
      if (use_kerberos)
	shishi_done (h);
      {
# ifdef ENCRYPTION
	if (doencrypt)
	  {
	    shishi_key_done (enckey);
	    for (i = 0; i < 4; i++)
	      {
		shishi_crypto_close (ivtab[i]->ctx);
		free (ivtab[i]->iv);
	      }
	  }
# endif/* ENCRYPTION */
      }
#endif /* SHISHI */
    }
}

static int
write_stat_time (int fd, struct stat *stat)
{
  char buf[4 * sizeof (long) * 3 + 2];
  time_t a_sec, m_sec;
  long a_usec = 0, m_usec = 0;

  a_sec = stat->st_atime;
#ifdef HAVE_STRUCT_STAT_ST_ATIM_TV_NSEC
  a_usec = stat->st_atim.tv_nsec / 1000;
#elif defined HAVE_STRUCT_STAT_ST_ATIM_TV_USEC
  a_usec = stat->st_atim.tv_usec;
#endif

  m_sec = stat->st_mtime;
#ifdef HAVE_STRUCT_STAT_ST_MTIM_TV_NSEC
  m_usec = stat->st_mtim.tv_nsec / 1000;
#elif defined HAVE_STRUCT_STAT_ST_MTIM_TV_USEC
  m_usec = stat->st_mtim.tv_usec;
#endif

  snprintf (buf, sizeof (buf), "T%ld %ld %ld %ld\n",
	    m_sec, m_usec, a_sec, a_usec);
  return write (fd, buf, strlen (buf));
}

void
source (int argc, char *argv[])
{
  struct stat stb;
  static BUF buffer;
  BUF *bp;
  off_t i;
  int amt, fd, haderr, indx, result;
  char *last, *name, buf[BUFSIZ];

  for (indx = 0; indx < argc; ++indx)
    {
      name = argv[indx];
      fd = open (name, O_RDONLY, 0);
      if (fd < 0)
	goto syserr;
      if (fstat (fd, &stb))
	{
	syserr:
	  run_err ("%s: %s", name, strerror (errno));
	  goto next;
	}
      switch (stb.st_mode & S_IFMT)
	{
	case S_IFREG:
	  break;

	case S_IFDIR:
	  if (iamrecursive)
	    {
	      rsource (name, &stb);
	      goto next;
	    }
	default:
	  run_err ("%s: not a regular file", name);
	  goto next;
	}
      last = strrchr (name, '/');
      if (last == NULL)
	last = name;
      else
	++last;
      if (preserve_option)
	{
	  write_stat_time (rem, &stb);
	  if (response () < 0)
	    goto next;
	}
#define RCP_MODEMASK	(S_ISUID|S_ISGID|S_ISVTX|S_IRWXU|S_IRWXG|S_IRWXO)
      snprintf (buf, sizeof buf, "C%04o %jd %s\n",
		(int) stb.st_mode & RCP_MODEMASK, (intmax_t) stb.st_size,
		last);
      write (rem, buf, strlen (buf));
      if (response () < 0)
	goto next;

      bp = allocbuf (&buffer, fd, BUFSIZ);
      if (bp == NULL)
	{
	next:
	  close (fd);
	  continue;
	}

      /* Keep writing after an error so that we stay sync'd up. */
      for (haderr = i = 0; i < stb.st_size; i += bp->cnt)
	{
	  amt = bp->cnt;
	  if (i + amt > stb.st_size)
	    amt = stb.st_size - i;
	  if (!haderr)
	    {
	      result = read (fd, bp->buf, amt);
	      if (result != amt)
		haderr = result >= 0 ? EIO : errno;
	    }
	  if (haderr)
	    write (rem, bp->buf, amt);
	  else
	    {
	      result = write (rem, bp->buf, amt);
	      if (result != amt)
		haderr = result >= 0 ? EIO : errno;
	    }
	}
      if (close (fd) && !haderr)
	haderr = errno;
      if (!haderr)
	write (rem, "", 1);
      else
	run_err ("%s: %s", name, strerror (haderr));
      response ();
    }
}

void
rsource (char *name, struct stat *statp)
{
  DIR *dirp;
  struct dirent *dp;
  char *last, *vect[1];
  char *buf;
  int buf_len;

  dirp = opendir (name);
  if (!dirp)
    {
      run_err ("%s: %s", name, strerror (errno));
      return;
    }
  last = strrchr (name, '/');
  if (last == 0)
    last = name;
  else
    last++;

  if (preserve_option)
    {
      write_stat_time (rem, statp);
      if (response () < 0)
	{
	  closedir (dirp);
	  return;
	}
    }

  buf_len =
    1 + sizeof (int) * 3 + 1 + sizeof (int) * 3 + 1 + strlen (last) + 2;
  buf = malloc (buf_len);
  if (!buf)
    {
      run_err ("malloc failed for %d bytes", buf_len);
      closedir (dirp);
      return;
    }

  sprintf (buf, "D%04o %d %s\n", (int) statp->st_mode & RCP_MODEMASK, 0,
	   last);
  write (rem, buf, strlen (buf));
  free (buf);

  if (response () < 0)
    {
      closedir (dirp);
      return;
    }

  while ((dp = readdir (dirp)))
    {
      if (!strcmp (dp->d_name, ".") || !strcmp (dp->d_name, ".."))
	continue;

      buf_len = strlen (name) + 1 + strlen (dp->d_name) + 1;
      buf = malloc (buf_len);
      if (!buf)
	{
	  run_err ("malloc_failed for %d bytes", buf_len);
	  continue;
	}

      sprintf (buf, "%s/%s", name, dp->d_name);
      vect[0] = buf;

      source (1, vect);

      free (buf);
    }

  closedir (dirp);
  write (rem, "E\n", 2);
  response ();
}

void
sink (int argc, char *argv[])
{
  static BUF buffer;
  struct stat stb;
  struct timeval tv[2];
  enum
  { YES, NO, DISPLAYED } wrerr;
  BUF *bp;
  off_t i, j, size;
  int amt, count, exists, first, mask, mode, ofd, omode;
  int setimes, targisdir, wrerrno;
  char ch, *cp, *np, *targ, *vect[1], buf[BUFSIZ];
  const char *why;

#define atime	tv[0]
#define mtime	tv[1]
#define SCREWUP(str)	{ why = str; goto screwup; }

  setimes = targisdir = 0;
  mask = umask (0);
  if (!preserve_option)
    umask (mask);
  if (argc != 1)
    {
      run_err ("ambiguous target");
      exit (EXIT_FAILURE);
    }
  targ = *argv;
  if (targetshouldbedirectory)
    verifydir (targ);
  write (rem, "", 1);
  if (stat (targ, &stb) == 0 && S_ISDIR (stb.st_mode))
    targisdir = 1;
  for (first = 1;; first = 0)
    {
      cp = buf;
      if (read (rem, cp, 1) <= 0)
	return;
      if (*cp++ == '\n')
	SCREWUP ("unexpected <newline>");
      do
	{
	  if (read (rem, &ch, sizeof ch) != sizeof ch)
	    SCREWUP ("lost connection");
	  *cp++ = ch;
	}
      while (cp < &buf[BUFSIZ - 1] && ch != '\n');
      *cp = 0;

      if (buf[0] == '\01' || buf[0] == '\02')
	{
	  if (iamremote == 0)
	    write (STDERR_FILENO, buf + 1, strlen (buf + 1));
	  if (buf[0] == '\02')
	    exit (EXIT_FAILURE);
	  ++errs;
	  continue;
	}
      if (buf[0] == 'E')
	{
	  write (rem, "", 1);
	  return;
	}

      if (ch == '\n')
	*--cp = 0;

#define getnum(t) (t) = 0; while (isdigit(*cp)) (t) = (t) * 10 + (*cp++ - '0');
      cp = buf;
      if (*cp == 'T')
	{
	  setimes++;
	  cp++;
	  getnum (mtime.tv_sec);
	  if (*cp++ != ' ')
	    SCREWUP ("mtime.sec not delimited");
	  getnum (mtime.tv_usec);
	  if (*cp++ != ' ')
	    SCREWUP ("mtime.usec not delimited");
	  getnum (atime.tv_sec);
	  if (*cp++ != ' ')
	    SCREWUP ("atime.sec not delimited");
	  getnum (atime.tv_usec);
	  if (*cp++ != '\0')
	    SCREWUP ("atime.usec not delimited");
	  write (rem, "", 1);
	  continue;
	}
      if (*cp != 'C' && *cp != 'D')
	{
	  /*
	   * Check for the case "rcp remote:foo\* local:bar".
	   * In this case, the line "No match." can be returned
	   * by the shell before the rcp command on the remote is
	   * executed so the ^Aerror_message convention isn't
	   * followed.
	   */
	  if (first)
	    {
	      run_err ("%s", cp);
	      exit (EXIT_FAILURE);
	    }
	  SCREWUP ("expected control record");
	}
      mode = 0;
      for (++cp; cp < buf + 5; cp++)
	{
	  if (*cp < '0' || *cp > '7')
	    SCREWUP ("bad mode");
	  mode = (mode << 3) | (*cp - '0');
	}
      if (*cp++ != ' ')
	SCREWUP ("mode not delimited");

      for (size = 0; isdigit (*cp);)
	size = size * 10 + (*cp++ - '0');
      if (*cp++ != ' ')
	SCREWUP ("size not delimited");
      if (targisdir)
	{
	  static char *namebuf = NULL;
	  static size_t cursize = 0;
	  size_t need;

	  need = strlen (targ) + strlen (cp) + 250;
	  if (need > cursize)
	    {
	      if (!(namebuf = malloc (need)))
		run_err ("%s", strerror (errno));
	    }
	  snprintf (namebuf, need, "%s%s%s", targ, *targ ? "/" : "", cp);
	  np = namebuf;
	}
      else
	np = targ;
      exists = stat (np, &stb) == 0;
      if (buf[0] == 'D')
	{
	  int mod_flag = preserve_option;
	  if (exists)
	    {
	      if (!S_ISDIR (stb.st_mode))
		{
		  errno = ENOTDIR;
		  goto bad;
		}
	      if (preserve_option)
		chmod (np, mode);
	    }
	  else
	    {
	      /* Handle copying from a read-only directory */
	      mod_flag = 1;
	      if (mkdir (np, mode | S_IRWXU) < 0)
		goto bad;
	    }
	  vect[0] = np;
	  sink (1, vect);
	  if (setimes)
	    {
#ifndef HAVE_UTIMES
	      struct utimbuf utbuf;
	      utbuf.actime = atime.tv_sec;
	      utbuf.modtime = mtime.tv_sec;
#endif
	      setimes = 0;
#ifdef HAVE_UTIMES
	      if (utimes (np, tv) < 0)
#else
	      if (utime (np, &utbuf) < 0)
#endif
		run_err ("%s: set times: %s", np, strerror (errno));
	    }
	  if (mod_flag)
	    chmod (np, mode);
	  continue;
	}
      omode = mode;
      mode |= S_IWRITE;
      ofd = open (np, O_WRONLY | O_CREAT, mode);
      if (ofd < 0)
	{
	bad:
	  run_err ("%s: %s", np, strerror (errno));
	  continue;
	}
      write (rem, "", 1);
      bp = allocbuf (&buffer, ofd, BUFSIZ);
      if (bp == NULL)
	{
	  close (ofd);
	  continue;
	}
      cp = bp->buf;
      wrerr = NO;
      for (count = i = 0; i < size; i += BUFSIZ)
	{
	  amt = BUFSIZ;
	  if (i + amt > size)
	    amt = size - i;
	  count += amt;
	  do
	    {
	      j = read (rem, cp, amt);
	      if (j <= 0)
		{
		  run_err ("%s", j ? strerror (errno) : "dropped connection");
		  exit (EXIT_FAILURE);
		}
	      amt -= j;
	      cp += j;
	    }
	  while (amt > 0);
	  if (count == bp->cnt)
	    {
	      /* Keep reading so we stay sync'd up. */
	      if (wrerr == NO)
		{
		  j = write (ofd, bp->buf, count);
		  if (j != count)
		    {
		      wrerr = YES;
		      wrerrno = j >= 0 ? EIO : errno;
		    }
		}
	      count = 0;
	      cp = bp->buf;
	    }
	}
      if (count != 0 && wrerr == NO
	  && (j = write (ofd, bp->buf, count)) != count)
	{
	  wrerr = YES;
	  wrerrno = j >= 0 ? EIO : errno;
	}
      if (ftruncate (ofd, size))
	{
	  run_err ("%s: truncate: %s", np, strerror (errno));
	  wrerr = DISPLAYED;
	}
      if (preserve_option)
	{
	  if (exists || omode != mode)
	    if (fchmod (ofd, omode))
	      run_err ("%s: set mode: %s", np, strerror (errno));
	}
      else
	{
	  if (!exists && omode != mode)
	    if (fchmod (ofd, omode & ~mask))
	      run_err ("%s: set mode: %s", np, strerror (errno));
	}
      close (ofd);
      response ();
      if (setimes && wrerr == NO)
	{
#ifndef HAVE_UTIMES
	  struct utimbuf utbuf;
	  utbuf.actime = atime.tv_sec;
	  utbuf.modtime = mtime.tv_sec;
#endif
	  setimes = 0;
#ifdef HAVE_UTIMES
	  if (utimes (np, tv) < 0)
	    {
#else
	  if (utime (np, &utbuf) < 0)
	    {
#endif
	      run_err ("%s: set times: %s", np, strerror (errno));
	      wrerr = DISPLAYED;
	    }
	}
      switch (wrerr)
	{
	case YES:
	  run_err ("%s: %s", np, strerror (wrerrno));
	  break;

	case NO:
	  write (rem, "", 1);
	  break;

	case DISPLAYED:
	  break;
	}
    }
screwup:
  run_err ("protocol error: %s", why);
  exit (EXIT_FAILURE);
}

#if defined KERBEROS || defined SHISHI
int
kerberos (char **host, char *bp, char *locuser, char *user)
{
  int krb_errno = 0;
  struct servent *sp;

again:
  if (use_kerberos)
    {
      errno = 0;
# ifdef KERBEROS
      rem = KSUCCESS;
      if (dest_realm == NULL)
	dest_realm = krb_realmofhost (*host);
# elif defined SHISHI
      rem = SHISHI_OK;
# endif
# ifdef ENCRYPTION
      if (doencrypt)
	{
#  ifdef KERBEROS
	rem = krcmd_mutual (host, port, user, bp, 0, dest_realm, &cred, schedule):
	  krb_errno =
	    errno;
#  elif defined SHISHI
	  int i;
	  char *xbp = NULL;

	  xbp = xmalloc (strlen (bp) + sizeof ("-x "));
	  sprintf (xbp, "%s%s", "-x ", bp);
	  rem = krcmd_mutual (&h, host, port, &user, xbp, NULL,
			      dest_realm, &enckey, family);
	  krb_errno = errno;
	  if (rem > 0)
	    {
	      keytype = shishi_key_type (enckey);
	      keylen = shishi_cipher_blocksize (keytype);

	      ivtab[0] = &iv1;
	      ivtab[1] = &iv2;
	      ivtab[2] = &iv3;
	      ivtab[3] = &iv4;

	      for (i = 0; i < 4; i++)
		{
		  ivtab[i]->ivlen = keylen;

		  switch (keytype)
		    {
		    case SHISHI_DES_CBC_CRC:
		    case SHISHI_DES_CBC_MD4:
		    case SHISHI_DES_CBC_MD5:
		    case SHISHI_DES_CBC_NONE:
		    case SHISHI_DES3_CBC_HMAC_SHA1_KD:
		      ivtab[i]->keyusage = SHISHI_KEYUSAGE_KCMD_DES;
		      ivtab[i]->iv = xmalloc (ivtab[i]->ivlen);
		      memset (ivtab[i]->iv,
			      2 * i + 1 * (i < 2) - 4 * (i >= 2),
			      ivtab[i]->ivlen);
		      ivtab[i]->ctx =
			shishi_crypto (h, enckey, ivtab[i]->keyusage,
				       shishi_key_type (enckey), ivtab[i]->iv,
				       ivtab[i]->ivlen);
		      break;
		    case SHISHI_ARCFOUR_HMAC:
		    case SHISHI_ARCFOUR_HMAC_EXP:
		      ivtab[i]->keyusage =
			SHISHI_KEYUSAGE_KCMD_DES + 2 + 4 * i;
		      ivtab[i]->ctx =
			shishi_crypto (h, enckey, ivtab[i]->keyusage,
				       shishi_key_type (enckey), NULL, 0);
		      break;
		    default:
		      ivtab[i]->keyusage =
			SHISHI_KEYUSAGE_KCMD_DES + 2 + 4 * i;
		      ivtab[i]->iv = xmalloc (ivtab[i]->ivlen);
		      memset (ivtab[i]->iv, 0, ivtab[i]->ivlen);
		      ivtab[i]->ctx =
			shishi_crypto (h, enckey, ivtab[i]->keyusage,
				       shishi_key_type (enckey), ivtab[i]->iv,
				       ivtab[i]->ivlen);
		    }
		}
	    }
	  free (xbp);
#  endif
	}
      else
# endif/* ENCRYPTION */
	{
# ifdef KERBEROS
	  rem = krcmd (host, port, user, bp, 0, dest_realm);
# else/* SHISHI */
	  rem = krcmd (&h, host, port, &user, bp, NULL, dest_realm, family);
# endif
	  krb_errno = errno;
	}

      if (rem < 0)
	{
	  use_kerberos = 0;
	  if (krb_errno == ECONNREFUSED)
	    oldw ("remote host doesn't support Kerberos");
	  else if (krb_errno == ENOENT)
	    error (EXIT_FAILURE, 0,
		   "Can't provide Kerberos authentication data.");
	  else
	    error (EXIT_FAILURE, 0, "Kerberos authentication failed.");

	  sp = getservbyname ("shell", "tcp");
	  if (sp == NULL)
	    error (EXIT_FAILURE, 0, "unknown service shell/tcp");
	  port = sp->s_port;
	  goto again;
	}
    }
  else
    {
      char *p = strchr (*host, '/');

# ifdef ENCRYPTION
      if (doencrypt)
	error (EXIT_FAILURE, 0,
	       "the -x option requires Kerberos authentication");
# endif
      if (p)
	*host = ++p;		/* Skip prefix like `host/'.  */
# ifdef WITH_ORCMD_AF
      rem = orcmd_af (host, port, locuser, user, bp, 0, family);
# elif defined WITH_RCMD_AF
      rem = rcmd_af (host, port, locuser, user, bp, 0, family);
# elif defined WITH_ORCMD
      rem = orcmd (host, port, locuser, user, bp, 0);
# else/* !WITH_ORCMD_AF && !WITH_RCMD_AF && !WITH_ORCMD */
      rem = rcmd (host, port, locuser, user, bp, 0);
# endif
    }
  return rem;
}
#endif /* KERBEROS || SHISHI */

int
response (void)
{
  char ch, *cp, resp, rbuf[BUFSIZ];

  if (read (rem, &resp, sizeof resp) != sizeof resp)
    lostconn (0);

  cp = rbuf;
  switch (resp)
    {
    case 0:			/* ok */
      return 0;

    default:
      *cp++ = resp;
    case 1:			/* error, followed by error msg */
    case 2:			/* fatal error, "" */
      do
	{
	  if (read (rem, &ch, sizeof (ch)) != sizeof (ch))
	    lostconn (0);
	  *cp++ = ch;
	}
      while (cp < &rbuf[BUFSIZ] && ch != '\n');

      if (!iamremote)
	write (STDERR_FILENO, rbuf, cp - rbuf);
      ++errs;
      if (resp == 1)
	return -1;
      exit (EXIT_FAILURE);
    }
}

#if defined KERBEROS || defined SHISHI
void
oldw (const char *fmt, ...)
{
  va_list ap;

  va_start (ap, fmt);
  fprintf (stderr, "rcp: ");
  vfprintf (stderr, fmt, ap);
  fprintf (stderr, ", using standard rcp\n");
  va_end (ap);
}
#endif /* KERBEROS || SHISHI */

void
run_err (const char *fmt, ...)
{
  static FILE *fp;
  va_list ap;

  va_start (ap, fmt);

  ++errs;
  if (fp == NULL && !(fp = fdopen (rem, "w")))
    return;
  fprintf (fp, "%c", 0x01);
  fprintf (fp, "rcp: ");
  vfprintf (fp, fmt, ap);
  va_end (ap);
  fprintf (fp, "\n");
  fflush (fp);

  if (!iamremote)
    {
      fprintf (stderr, "%s: ", program_invocation_name);
      va_start (ap, fmt);
      vfprintf (stderr, fmt, ap);
      va_end (ap);
      fprintf (stderr, "\n");
    }
}

char *
colon (char *cp)
{
  if (*cp == ':')		/* Leading colon is part of file name. */
    return (0);

  for (; *cp; ++cp)
    {
      if (*cp == ':')
	return (cp);
      if (*cp == '/')
	return (0);
    }
  return (0);
}

void
verifydir (char *cp)
{
  struct stat stb;

  if (!stat (cp, &stb))
    {
      if (S_ISDIR (stb.st_mode))
	return;
      errno = ENOTDIR;
    }
  run_err ("%s: %s", cp, strerror (errno));
  exit (EXIT_FAILURE);
}

int
okname (char *cp0)
{
  int c;
  char *cp;

  cp = cp0;
  do
    {
      c = *cp;
      if (c & 0200)
	goto bad;
      if (!isalpha (c) && !isdigit (c) && c != '_' && c != '-')
	goto bad;
    }
  while (*++cp);
  return (1);

bad:
  error (0, 0, "%s: invalid user name", cp0);
  return (0);
}

int
susystem (char *s, int userid)
{
  sighandler_t istat, qstat;
  int status;
  pid_t pid;

  pid = vfork ();
  switch (pid)
    {
    case -1:
      return (127);

    case 0:
      if (setuid (userid) == -1)
	{
	  error (EXIT_FAILURE, 0,
		 "Could not drop privileges (setuid() failed)");
	}

      execl (PATH_BSHELL, "sh", "-c", s, NULL);
      _exit (127);
    }
  istat = signal (SIGINT, SIG_IGN);
  qstat = signal (SIGQUIT, SIG_IGN);
  if (waitpid (pid, &status, 0) < 0)
    status = -1;
  signal (SIGINT, istat);
  signal (SIGQUIT, qstat);
  return (status);
}

BUF *
allocbuf (BUF *bp, int fd, int blksize)
{
  struct stat stb;
  size_t size;

  if (fstat (fd, &stb) < 0)
    {
      run_err ("fstat: %s", strerror (errno));
      return (0);
    }
#ifndef roundup
# define roundup(x, y)   ((((x)+((y)-1))/(y))*(y))
#endif
  size = roundup (BUFSIZ, blksize);
  if (size == 0)
    size = blksize;
  if ((size_t) bp->cnt >= size)
    return (bp);

  bp->buf = realloc (bp->buf, size);
  if (bp->buf == NULL)
    {
      bp->cnt = 0;
      run_err ("%s", strerror (errno));
      return (0);
    }
  bp->cnt = size;
  return (bp);
}

void
lostconn (int signo MAYBE_UNUSED)
{
  if (!iamremote)
    error (0, 0, "lost connection");
  exit (EXIT_FAILURE);
}
