/* * Copyright 1994 David A. Barrett. * * Connect to a remote login program which requires response to a crypto * challenge.  Communicate subsequently via a DES encrypted channel. */#define _POSIX_SOURCE#include <unistd.h>	/* close getlogin */#include <stdlib.h>	/* atexit exit */#include <stdio.h>#include <string.h>#include <errno.h>#include <signal.h>#include <sys/types.h>	/* for fcntl.h */#include <fcntl.h>#include <termios.h>#include "posignal.h"#include "tty.h"#include "auth.h"#include "txfr.h"#include "socket.h"#include "deslogin.h"#include "utmp.h"extern int  optind;extern char *optarg;#if defined(__STDC__) || defined(__cplusplus)extern int askTty(char *, char *, unsigned, int);#elseextern int askTty();#endifstatic char ident[] = " @(#) deslogin.c   version 1.32 03-Mar-95 Copyright 1995 by Dave Barrett(barrett@asgard.cs.Colorado.EDU)\n";static char RCSid[] =    " @(#) deslogin.c  RCS: $Revision: 1.8 $ $Date: 95/03/08 01:13:04 $\n";char *progName;int  debug = 0;int  verbose = 0;char unknownLoginName[] = "unknown";unsigned long inBytes = 0;		/* for txfr */unsigned long outBytes = 0;struct termios oldmodes;int fixfd = -1;void fixtty(){   register int res;   if (fixfd >= 0) {      res = restoreTty(fixfd, &oldmodes);   }}void handler(sig)   int sig;{   exit(0);		/* calls fixtty via atexit */}/* * Perform a client handshake with the server */char *clientHandshake(nfd, string1, string2)   int nfd;   char *string1, *string2;{   int count, res;   static char protover[VERS_SIZE];   count = getString(nfd, protover, VERS_SIZE-1, SETUP_TIMEOUT);   if (count == 0) {      fprintf(stderr, "%s: network read of (protover) failed--%s\n", 	  progName, ERRMSG);      return 0;   }   res = write(nfd, PROTOCOL_VERS, strlen(PROTOCOL_VERS)+1);   if (res < 0) {      fprintf(stderr, "%s: gateway network write of \"%s\" failed--%s\n", 	 progName, PROTOCOL_VERS, ERRMSG);      return 0;   }   if (protover[0] != PROTOCOL_VERS[0]) {      fprintf(stderr, 	 "%s: remote protocol version (%s) incompatable with local (%s)\n",	  progName, protover, PROTOCOL_VERS);      return 0;   }   res = write(nfd, string1, strlen(string1)+1);   if (res < 0) {      fprintf(stderr, "%s: gateway network write of \"%s\" failed--%s\n", 	 progName, string1, ERRMSG);      return 0;   }   res = write(nfd, string2, strlen(string2)+1);   if (res < 0) {      fprintf(stderr, "%s: gateway network write of \"%s\" failed--%s\n", 	  progName, string2, ERRMSG);      return 0;   }   return protover;}int main(argc, argv)   int argc;   char *argv[];{   int ch, count, res;   unsigned bufSize = 127;   char aport[16];   char *chp, *hostName = (char *) 0, *gateway = (char *) 0;   char *loginName, *ruser = (char *) 0;   int nfd, port = DESLOGIN_PORT, gport = 0, loginLen, userLen;   char passPhrase[PHRASE_SIZE], target[128], *tp = (char *) 0;   keyType key;   progName = *argv;   if ((chp = strrchr(progName, '/')) != (char *) 0) progName = chp + 1;   while ((ch = getopt(argc, argv, "dvh:g:")) != EOF) switch (ch) {   case 'h':      tp = optarg;      break;   case 'g':      gateway = optarg;      break;   case 'v':      verbose++;      break;   case 'd':      debug++;      break;   default:usage:      fprintf(stderr, 	 "usage: %s [-dvt] [-g gateway] [ [user@]domain[:port] ]\n", 	 progName);      exit(1);   }   argc -= optind;   argv += optind;   if (argc != 0) {      tp = *argv++; --argc;   }   if (tp == (char *) 0) {      res = askTty("Input destination <[user@]domain[:port]>:", 	 target, 128-1, 1);      if (res < 0) {	 fprintf(stderr, "%s: couldn't get destination\n", progName);	 exit(1);      }      tp = target;   }   chp = strchr(tp, '@');   if (chp != (char *) 0) {      *chp = '\0';      ruser     = tp;      hostName  = chp+1;   } else {      hostName  = tp;   }   chp = strchr(hostName, ':');   if (chp != (char *) 0) {      *chp = '\0';      count = sscanf(chp+1, "%u", &port);      if (count != 1) goto usage;   }   sprintf(aport, "%d", port);   loginName = (char *) getLoginName();		/* NOT getlogin!; see utmp.c */   if (loginName == (char *) 0) {      fprintf(stderr, "%s: Warning--getLoginName failed\n", progName);      loginName = unknownLoginName;   }   loginLen = strlen(loginName);   if (ruser == (char *) 0) {      ruser = loginName;      if (loginName == unknownLoginName) {	 fprintf(stderr, 	 "%s: unknown local login name; must specify remote user\n", progName);	 exit(1);      }   }   userLen = strlen(ruser);   if (gateway != (char *) 0) {      chp = strchr(gateway, ':');      if (chp != (char *) 0) {	 *chp = '\0';	 count = sscanf(chp+1, "%u", &gport);	 if (count != 1) goto usage;      }      if (gport == 0) {	 gport = getServicePort(GW_SERVICE_NAME);	 if ((int) gport < 0) {	    gport = DESLOGIN_GW_PORT;	 }      }      nfd = openClient(gateway, gport);      if (nfd < 0) {	 fprintf(stderr, "%s: open gateway %s:%d failed --%s\n", 	    progName, gateway, gport, ERRMSG);	 exit(1);      }      res = askTty("Gateway Pass phrase: ", passPhrase, PHRASE_SIZE-1, 0);      if (res < 0) {	 fprintf(stderr, "%s: couldn't get pass phrase\n", progName);	 exit(1);      }      key = signature(nfd, passPhrase, SETUP_TIMEOUT);      memset(passPhrase, '\0', PHRASE_SIZE);      destroyKey(&key);      chp = clientHandshake(nfd, hostName, aport);      if (!chp) {	 exit(1);      }   } else {      nfd = openClient(hostName, port);      if (nfd < 0) {	 exit(1);      }   }   chp = clientHandshake(nfd, loginName, ruser);   if (!chp) {      exit(1);   }   res = askTty("Pass phrase: ", passPhrase, PHRASE_SIZE-1, 0);   if (res < 0) {      fprintf(stderr, "%s: couldn't get pass phrase\n", progName);      exit(1);   }   key = signature(nfd, passPhrase, SETUP_TIMEOUT);   memset(passPhrase, '\0', PHRASE_SIZE);   /*    * If unsuccessful, the remote side will shut down the connection which    * will cause the rest of the program to exit    *    * There is a strange interaction between two fd's associated with the    * same device.  They will share the same modes.  Thus, only one of    * these modes must be saved or restored.    */   if (isTty(0)) {      fixfd = 0;   } else if (isTty(1)) {      fixfd = 1;   }   if (fixfd >= 0) {      res = setTtyBin(fixfd, &oldmodes);      if (res < 0) {	 fprintf(stderr, "%s: setTtyBin failed to fd %d--%s\n", 	    progName, fixfd, ERRMSG);	 exit(1);      }      res = atexit(fixtty);      if (res == -1) {	 fprintf(stderr, "%s: atexit failed--%s\n", progName, ERRMSG);	 exit(1);      }   }   chp = (char *) posignal(SIGINT, handler);   if (chp == (char *) -1L) {      fprintf(stderr, "%s: sigaction failed--%s\n", progName, ERRMSG);      exit(1);   }   res = txfr(nfd, 0, 1, bufSize, 0, key);   destroyKey(&key);   if (isTty(1)) {      write(1, "\r\nConnection closed.\r\n", 22);   }   exit(0);			/* to ensure that atexit is called */   return 0;}