# ifdef lint
static char sccsid[] = "@(#)on.c 1.1 94/10/31 Copyr 1985 Sun Micro";
# endif lint

/*
 * on - user interface program for remote execution service
 *
 * Copyright (c) 1985 Sun Microsystems, Inc.
 */

#include <stdio.h>
#include <signal.h>
#include <sys/param.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/fcntl.h>
#include <rpc/rpc.h>
#include <rpc/key_prot.h>
#include <netdb.h>
#include <errno.h>
#include <ctype.h>

#include "rex.h"

# define CommandName "on"	/* given as argv[0] */
# define AltCommandName "dbon"

extern int errno;

/*
 * Note - the following must be long enough for at least two portmap
 * timeouts on the other side.
 */
struct timeval LongTimeout = { 123, 0 };

int Debug = 0;			/* print extra debugging information */
int Only2 = 0;			/* stdout and stderr are the same */
int Interactive = 0;		/* use a pty on server */
int NoInput = 0;		/* don't read standard input */

int InOut;			/* socket for stdin/stdout */
int Err;			/* socket for stderr */

struct sgttyb OldFlags;		/* saved tty flags */
struct sgttyb NewFlags;		/* for stop/continue job control */
CLIENT *Client;			/* RPC client handle */
struct ttysize WindowSize;	/* saved window size */


/*
 * window change handler - propagate to remote server 
 */
sigwinch()
{
     struct ttysize size;
     enum clnt_stat clstat;

     ioctl(0, TIOCGSIZE, &size);
     if (bcmp(&size,&WindowSize,sizeof size)==0) return;
     WindowSize = size;
     if (clstat = clnt_call(Client, REXPROC_WINCH,
    	xdr_rex_ttysize, &size, xdr_void, NULL, LongTimeout)) {
		fprintf(stderr, "on (size): ");
		clnt_perrno(clstat);
		fprintf(stderr, "\r\n");
     }
}

/*
 * signal handler - propagate to remote server 
 */
sendsig(sig)
     int sig;
{
     enum clnt_stat clstat;

     if (clstat = clnt_call(Client, REXPROC_SIGNAL,
    	xdr_int, &sig, xdr_void, NULL, LongTimeout)) {
		fprintf(stderr, "on (signal): ");
		clnt_perrno(clstat);
		fprintf(stderr, "\r\n");
     }
}

  
cont()
{
	/*
	 * Put tty modes back the way they were and tell the rexd server
	 * to send the command a SIGCONT signal.
	 */
	if (Interactive) {
		ioctl(0, TIOCSETN, &NewFlags);
		(void) send(InOut, "", 1, MSG_OOB);
	}
}

/*
 * oob -- called when the command invoked by the rexd server is stopped
 *	  with a SIGTSTP or SIGSTOP signal.
 */
oob()
{
	int atmark;
	char waste[BUFSIZ], mark;

	for (;;) {
		if (ioctl(InOut, SIOCATMARK, &atmark) < 0) {
			perror("ioctl");
			break;
		}
		if (atmark)
			break;
		(void) read(InOut, waste, sizeof (waste));
	}
	(void) recv(InOut, &mark, 1, MSG_OOB);
	/*
	 * Reset tty modes to something sane and stop myself
	 */
	if (Interactive) {
		ioctl(0, TIOCSETN, &OldFlags);
		printf("\r\n");
	}
	kill(getpid(), SIGSTOP);
}



main(argc, argv)
	int argc;
	char **argv;
{
	char *rhost, **cmdp;
	char curdir[MAXPATHLEN];
	char wdhost[MAXHOSTNAMELEN];
	char fsname[MAXPATHLEN];
	char dirwithin[MAXPATHLEN];
	struct rex_start rst;
	struct rex_result result;
	extern char **environ, *rindex();
	extern char *index();
	enum clnt_stat clstat;
	struct hostent *hp;
	struct sockaddr_in server_addr;
	int sock = RPC_ANYSOCK;
	int selmask, zmask, remmask;
	int nfds, cc;
	char *chi, *cho;
	int trying_authdes;
	char netname[MAXNETNAMELEN+1];
	char hostname[MAXHOSTNAMELEN+1];
	char publickey[HEXKEYBYTES+1];
	int i;
	char *domain;
	static char buf[4096];

	    /*
	     * we check the invoked command name to see if it should
	     * really be a host name.
	     */
	if ( (rhost = rindex(argv[0],'/')) == NULL) {
		rhost = argv[0];
	}
	else {
		rhost++;
	}

	while (argc > 1 && argv[1][0] == '-') {
	    switch (argv[1][1]) {
	      case 'd': Debug = 1;
	      		break;
	      case 'i': Interactive = 1;
	      		break;
	      case 'n': NoInput = 1;
	      		break;
	      default:
	      		printf("Unknown option %s\n",argv[1]);
	    }
	    argv++;
	    argc--;
	}
	if (strcmp(rhost,CommandName) && strcmp(rhost,AltCommandName)) {
	    cmdp = &argv[1];
	    Interactive = 1;
	} else {
	    if (argc < 2)
		usage();
	    rhost = argv[1];
	    cmdp = &argv[2];
	}

	/*
	 * Can only have one of these
	 */
	if (Interactive && NoInput)
		usage();

	if ((hp = gethostbyname(rhost)) == NULL) {
		fprintf(stderr, "on: unknown host %s\n", rhost);
		exit(1);
	}
	bcopy(hp->h_addr, (caddr_t)&server_addr.sin_addr, hp->h_length);
	server_addr.sin_family = AF_INET;
	server_addr.sin_port = 0;	/* use pmapper */
	if (Debug) printf("Got the host named %s (%s)\n",
			rhost,inet_ntoa(server_addr.sin_addr));
	trying_authdes = 1;

try_auth_unix:
	sock = RPC_ANYSOCK;
	if ((Client = clnttcp_create(&server_addr, REXPROG, REXVERS, &sock,
	    0, 0)) == NULL) {
		fprintf(stderr, "on: cannot connect to server on %s\n",
			rhost);
		exit(1);
	}

	if (Debug) printf("TCP RPC connection created\n");
	if (trying_authdes){
	yp_get_default_domain(&domain);

	cho =  hostname;
	*cho = 0;
	chi=  hp->h_name;

	for ( i = 0 ; (*chi && (i<MAXHOSTNAMELEN) );i++ ){
		if (isupper(*chi)) *cho=tolower(*chi);
		else *cho = *chi;
		cho++;
		chi++;
	}
	*cho=0;
	
	if (domain!= NULL){
		if (! host2netname(netname, hostname, domain)){
			trying_authdes = 0;
			if (Debug) printf("host2netname failed %s\n",hp->h_name);
		}
		else {
			if (getpublickey(netname, publickey) == 0) {
				trying_authdes = 0;
				cho=index(hostname , '.');
				if (cho){
					*cho=0;
					if (! host2netname(netname, hostname, domain)){
						if (Debug) printf("host2netname failed %s\n",hp->h_name);
					}
					else {
						if (getpublickey(netname, publickey) != 0) 
						trying_authdes = 1;
					}
				}
			}
		}

	}
	else {
		trying_authdes = 0;
		if (Debug) printf("yp_get_default_domain failed \n");
	}
	}
	if (trying_authdes){
	Client->cl_auth=authdes_create(netname,60*60, &server_addr, NULL);
		if (Client->cl_auth == NULL){
			if (Debug) printf("authdes_create failed %s\n",netname);
			trying_authdes = 0;
		}
	}


	if (trying_authdes == 0) Client->cl_auth = authunix_create_default();


	  /*
	   * Now that we have created the TCP connection, we do some
	   * work while the server daemon is being swapped in.
	   */
	if (getwd(curdir) == 0) {
		fprintf(stderr, "on: can't find . (%s)\n",curdir);
		exit(1);
	}
	if (findmount(curdir,wdhost,fsname,dirwithin) == 0) {
		fprintf(stderr, "on: can't locate mount point for %s (%s)\n",
				curdir, dirwithin);
		exit(1);
	}
	if (Debug) printf("wd host %s, fs %s, dir within %s\n",
		wdhost, fsname, dirwithin);

	Only2 = samefd(1,2);
	rst.rst_cmd = cmdp;
	rst.rst_env = environ;
	rst.rst_host = wdhost;
	rst.rst_fsname = fsname;
	rst.rst_dirwithin = dirwithin;
	rst.rst_port0 = makeport(&InOut);
	rst.rst_port1 =  rst.rst_port0;		/* same port for stdin */
	rst.rst_flags = 0;
	if (Interactive) {
		rst.rst_flags |= REX_INTERACTIVE;
		gtty(0, &OldFlags);
		gtty(0, &NewFlags);
		NewFlags.sg_flags |= RAW;
		NewFlags.sg_flags &= ~ECHO;
		stty(0, &NewFlags);
	}
	if (Only2) {
		rst.rst_port2 = rst.rst_port1;
	} else {
		rst.rst_port2 = makeport(&Err);
	}
	if (clstat = clnt_call(Client, REXPROC_START,
	    xdr_rex_start, &rst, xdr_rex_result, &result, LongTimeout)) {
		if (trying_authdes){
			auth_destroy(Client->cl_auth);
			CLNT_DESTROY(Client);
			trying_authdes=0;
			goto try_auth_unix;
		}
		else {
			fprintf(stderr, "on %s: ", rhost);
			clnt_perrno(clstat);
			fprintf(stderr, "\n");
			Die(1);
		}
	}
	if (result.rlt_stat != 0) {
		fprintf(stderr, "on %s: %s\r",rhost,result.rlt_message);
		Die(1);
	}
	if (Debug) printf("Client call was made\r\n");
	if (Interactive) {
	  /*
	   * Pass the tty modes along to the server 
	   */
	     struct rex_ttymode mode;
	     int err;

	     mode.basic = OldFlags;
	     err =  ( ioctl(0, TIOCGETC, &mode.more)<0 ||
		      ioctl(0, TIOCGLTC, &mode.yetmore)<0 ||
		      ioctl(0, TIOCLGET, &mode.andmore)<0 );
	     if (!err && (clstat = clnt_call(Client, REXPROC_MODES,
	    	xdr_rex_ttymode, &mode, xdr_void, NULL, LongTimeout))) {
			fprintf(stderr, "on (modes) %s: ", rhost);
			clnt_perrno(clstat);
			fprintf(stderr, "\r\n");
	     }
	     err = ioctl(0, TIOCGSIZE, &WindowSize) < 0;
	     if (!err && (clstat = clnt_call(Client, REXPROC_WINCH,
	    	xdr_rex_ttysize, &WindowSize, xdr_void, NULL, LongTimeout))) {
			fprintf(stderr, "on (size) %s: ", rhost);
			clnt_perrno(clstat);
			fprintf(stderr, "\r\n");
	     }
	     signal(SIGWINCH, sigwinch);
	     signal(SIGINT, sendsig);
	     signal(SIGQUIT, sendsig);
	     signal(SIGTERM, sendsig);
	}
 	signal(SIGCONT, cont);
	signal(SIGURG, oob);
	doaccept(&InOut);
	(void) fcntl(InOut, F_SETOWN, getpid());
	remmask = (1 << InOut);
	if (Debug) printf("accept on stdout\r\n");
	if (!Only2) {
		doaccept(&Err);
		shutdown(Err, 1);
		if (Debug) printf("accept on stderr\r\n");
		remmask |= (1 << Err);
	}
	if (NoInput) {
		  /*
		   * no input - simulate end-of-file instead
		   */
		zmask = 0;
		shutdown(InOut, 1);
	}
	else {
		  /*
		   * set up to read standard input, send to remote
		   */
		zmask = 1;
	}
	while (remmask) {
		selmask = remmask | zmask;
		nfds = select(32, &selmask, 0, 0, 0);
		if (nfds <= 0) {
			if (errno == EINTR) continue;
			perror("on: select");
			Die(1);
		}
		if (selmask & (1<<InOut)) {
			cc = read(InOut, buf, sizeof buf);
			if (cc > 0)
				write(1, buf, cc);
			else
				remmask &= ~(1<<InOut);
		}
		if (!Only2 && selmask & (1<<Err)) {
			cc = read(Err, buf, sizeof buf);
			if (cc > 0)
				write(2, buf, cc);
			else
				remmask &= ~(1<<Err);
		}
		if (!NoInput && selmask & (1<<0)) {
			cc = read(0, buf, sizeof buf);
			if (cc > 0)
				write(InOut, buf, cc);
			else {
				/*
				 * End of standard input - shutdown outgoing
				 * direction of the TCP connection.
				 */
				if (Debug)
			printf("Got EOF - shutting down connection\n");
				zmask = 0;
				shutdown(InOut, 1);
			}
		}
	}
	close(InOut);
	if (!Only2)
	    close(Err);
	if (clstat = clnt_call(Client, REXPROC_WAIT,
	    xdr_void, 0, xdr_rex_result, &result, LongTimeout)) {
		fprintf(stderr, "on: ");
		clnt_perrno(clstat);
		fprintf(stderr, "\r\n");
		Die(1);
	}
	Die(result.rlt_stat);
}

/*
 * like exit, but resets the terminal state first 
 */
Die(stat)
{
  if (Interactive) {
      ioctl(0, TIOCSETN, &OldFlags);
      printf("\r\n");
  }
  exit(stat);
}


remstop()
{
	Die(23);
}

  /*
   * returns true if we can safely say that the two file descriptors
   * are the "same" (both are same file).
   */
samefd(a,b)
{
    struct stat astat, bstat;
    if (fstat(a,&astat) || fstat(b,&bstat)) return(0);
    if (astat.st_ino == 0 || bstat.st_ino == 0) return(0);
    return( !bcmp( &astat, &bstat, sizeof(astat)) );
}


/*
 * accept the incoming connection on the given
 * file descriptor, and return the new file descritpor
 */
doaccept(fdp)
	int *fdp;
{
	int fd;

	fd = accept(*fdp, 0, 0);
	if (fd < 0) {
		perror("accept");
		remstop();
	}
	close(*fdp);
	*fdp = fd;
}

/*
 * create a socket, and return its the port number.
 */
makeport(fdp)
	int *fdp;
{
	struct sockaddr_in sin;
	int fd, len;

	fd = socket(AF_INET, SOCK_STREAM, 0);
	if (fd < 0) {
		perror("socket");
		exit(1);
	}
	bzero((char *)&sin, sizeof sin);
	sin.sin_family = AF_INET;
	bind(fd, &sin, sizeof sin);
	len = sizeof sin;
	getsockname(fd, &sin, &len);
	listen(fd, 1);
	*fdp = fd;
	return (htons(sin.sin_port));
}

usage()
{
    fprintf(stderr, "Usage: on [-i|-n] [-d] machine cmd [args]...\n");
    exit(1);
}