inetutils/libinetutils/kcmd.c

/*
 * Copyright (c) 1983, 1993
 *	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.
 * 4. 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.
 */

#ifndef lint
static char     Xsccsid[] = "derived from @(#)rcmd.c 5.17 (Berkeley) 6/27/88";
static char     sccsid[] = "@(#)kcmd.c	8.2 (Berkeley) 8/19/93";
#endif /* not lint */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#if defined(KERBEROS) || defined(SHISHI)

#include <sys/param.h>
#include <sys/file.h>
#include <sys/socket.h>
#include <sys/stat.h>

#include <netinet/in.h>
#include <arpa/inet.h>

#if defined(KERBEROS)
# include <kerberosIV/des.h>
# include <kerberosIV/krb.h>
#elif defined(SHISHI)
# include <shishi.h>
# include "shishi_def.h"
#endif

#include <ctype.h>
#include <errno.h>
#include <netdb.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#ifndef MAXHOSTNAMELEN
#define MAXHOSTNAMELEN 64
#endif

#define	START_PORT	5120	/* arbitrary */

int getport     __P ((int *));

#if defined (KERBEROS)
int
kcmd (int *sock, char **ahost, u_short rport, char *locuser,
      char *remuser, char *cmd, int *fd2p, KTEXT ticket,
      char *service, char *realm,
      CREDENTIALS * cred, Key_schedule schedule, MSG_DAT * msg_data,
      struct sockaddr_in *laddr, struct sockaddr_in *faddr, long authopts)
#elif defined(SHISHI)
int
kcmd (Shishi ** h, int *sock, char **ahost, u_short rport, char *locuser,
      char **remuser, char *cmd, int *fd2p, char *service, char *realm,
      Shishi_key ** key,
      struct sockaddr_in *laddr, struct sockaddr_in *faddr, long authopts)
#endif
{
  int             s, timo = 1, pid;
  long            oldmask;
  struct sockaddr_in sin, from;
  char            c;

#ifdef ATHENA_COMPAT
  int             lport = IPPORT_RESERVED - 1;
#else
  int             lport = START_PORT;
#endif
  struct hostent *hp;
  int             rc;
  char           *host_save;
  int             status;

#if defined(SHISHI)
  int             zero = 0;
#endif

  pid = getpid ();
  hp = gethostbyname (*ahost);
  if (hp == NULL)
    {
      /* fprintf(stderr, "%s: unknown host\n", *ahost); */
      return (-1);
    }

  host_save = malloc (strlen (hp->h_name) + 1);
  strcpy (host_save, hp->h_name);
  *ahost = host_save;

#ifdef KERBEROS
  /* If realm is null, look up from table */
  if (realm == NULL || realm[0] == '\0')
    realm = krb_realmofhost (host_save);
#endif /* KERBEROS */

  oldmask = sigblock (sigmask (SIGURG));
  for (;;)
    {
      s = getport (&lport);
      if (s < 0)
	{
	  if (errno == EAGAIN)
	    fprintf (stderr, "kcmd(socket): All ports in use\n");
	  else
	    perror ("kcmd: socket");
	  sigsetmask (oldmask);
	  return (-1);
	}
      fcntl (s, F_SETOWN, pid);
      sin.sin_family = hp->h_addrtype;
#if defined(ultrix) || defined(sun)
      bcopy (hp->h_addr, (caddr_t) & sin.sin_addr, hp->h_length);
#else
      bcopy (hp->h_addr_list[0], (caddr_t) & sin.sin_addr, hp->h_length);
#endif
      sin.sin_port = rport;

      if (connect (s, (struct sockaddr *) &sin, sizeof (sin)) >= 0)
	break;
      close (s);
      if (errno == EADDRINUSE)
	{
	  lport--;
	  continue;
	}
      /*
       * don't wait very long for Kerberos rcmd.
       */
      if (errno == ECONNREFUSED && timo <= 4)
	{
	  /* sleep(timo); don't wait at all here */
	  timo *= 2;
	  continue;
	}
#if !(defined(ultrix) || defined(sun))
      if (hp->h_addr_list[1] != NULL)
	{
	  int             oerrno = errno;

	  fprintf (stderr,
		   "kcmd: connect to address %s: ", inet_ntoa (sin.sin_addr));
	  errno = oerrno;
	  perror (NULL);
	  hp->h_addr_list++;
	  bcopy (hp->h_addr_list[0], (caddr_t) & sin.sin_addr, hp->h_length);
	  fprintf (stderr, "Trying %s...\n", inet_ntoa (sin.sin_addr));
	  continue;
	}
#endif /* !(defined(ultrix) || defined(sun)) */
      if (errno != ECONNREFUSED)
	perror (hp->h_name);
      sigsetmask (oldmask);

      return (-1);
    }
  lport--;
  if (fd2p == 0)
    {
      write (s, "", 1);
      lport = 0;
    }
  else
    {
      char            num[8];
      int             s2 = getport (&lport), s3;
      int             len = sizeof (from);

      if (s2 < 0)
	{
	  status = -1;
	  goto bad;
	}
      listen (s2, 1);
      sprintf (num, "%d", lport);
      if (write (s, num, strlen (num) + 1) != strlen (num) + 1)
	{
	  perror ("kcmd(write): setting up stderr");
	  close (s2);
	  status = -1;
	  goto bad;
	}
      s3 = accept (s2, (struct sockaddr *) &from, &len);
      close (s2);
      if (s3 < 0)
	{
	  perror ("kcmd:accept");
	  lport = 0;
	  status = -1;
	  goto bad;
	}
      *fd2p = s3;
      from.sin_port = ntohs ((u_short) from.sin_port);
      if (from.sin_family != AF_INET || from.sin_port >= IPPORT_RESERVED)
	{
	  fprintf (stderr,
		   "kcmd(socket): protocol failure in circuit setup.\n");
	  status = -1;
	  goto bad2;
	}
    }
  /*
   * Kerberos-authenticated service.  Don't have to send locuser,
   * since its already in the ticket, and we'll extract it on
   * the other side.
   */
  /* write(s, locuser, strlen(locuser)+1); */

  /* set up the needed stuff for mutual auth, but only if necessary */
#ifdef KERBEROS
  if (authopts & KOPT_DO_MUTUAL)
    {
      int             sin_len;

      *faddr = sin;

      sin_len = sizeof (struct sockaddr_in);
      if (getsockname (s, (struct sockaddr *) laddr, &sin_len) < 0)
	{
	  perror ("kcmd(getsockname)");
	  status = -1;
	  goto bad2;
	}
    }

  if ((status = krb_sendauth (authopts, s, ticket, service, *ahost,
			      realm, (unsigned long) getpid (), msg_data,
			      cred, schedule,
			      laddr, faddr, "KCMDV0.1")) != KSUCCESS)
    goto bad2;
#elif defined(SHISHI)
  if (authopts & SHISHI_APOPTIONS_MUTUAL_REQUIRED)
    {
      int             sin_len;

      *faddr = sin;

      sin_len = sizeof (struct sockaddr_in);
      if (getsockname (s, (struct sockaddr *) laddr, &sin_len) < 0)
	{
	  perror ("kcmd(getsockname)");
	  status = -1;
	  goto bad2;
	}
    }

  if ((status =
       shishi_auth (h, 0, remuser, *ahost, s, cmd, rport, key,
		    realm)) != SHISHI_OK)
    goto bad2;

#endif /* SHISHI */

  write (s, *remuser, strlen (*remuser) + 1);
  write (s, cmd, strlen (cmd) + 1);

#ifdef SHISHI
  write (s, *remuser, strlen (*remuser) + 1);
  write (s, &zero, sizeof (int));
#endif

  if ((rc = read (s, &c, 1)) != 1)
    {
      if (rc == -1)
	perror (*ahost);
      else
	fprintf (stderr, "kcmd: bad connection with remote host\n");
      status = -1;
      goto bad2;
    }
  if (c != '\0')
    {
      while (read (s, &c, 1) == 1)
	{
	  write (2, &c, 1);
	  if (c == '\n')
	    break;
	}
      status = -1;
      goto bad2;
    }
  sigsetmask (oldmask);
  *sock = s;
#if defined(KERBEROS)
  return (KSUCCESS);
#elif defined(SHISHI)
  return (SHISHI_OK);
#endif
bad2:
  if (lport)
    close (*fd2p);
bad:
  close (s);
  sigsetmask (oldmask);
  return (status);
}

int
getport (int *alport)
{
  struct sockaddr_in sin;
  int             s;

  sin.sin_family = AF_INET;
  sin.sin_addr.s_addr = INADDR_ANY;
  s = socket (AF_INET, SOCK_STREAM, 0);
  if (s < 0)
    return (-1);
  for (;;)
    {
      sin.sin_port = htons ((u_short) * alport);
      if (bind (s, (struct sockaddr *) &sin, sizeof (sin)) >= 0)
	return (s);
      if (errno != EADDRINUSE)
	{
	  close (s);
	  return (-1);
	}
      (*alport)--;
#ifdef ATHENA_COMPAT
      if (*alport == IPPORT_RESERVED / 2)
	{
#else
      if (*alport == IPPORT_RESERVED)
	{
#endif
	  close (s);
	  errno = EAGAIN;	/* close */
	  return (-1);
	}
    }
}

#endif /* KERBEROS */