/*
 *	RSHD.C -- Phil Budne @ BostonU / Distributed Systems
 *	BSD Un*x style remote shell daemon for Twenex
 *
 *	(c) 1986 Boston University.
 *	Permission granted to copy for non-profit use.
 *
 *	Written using UTAH PCC-20. Link with RSHLIB.
 *
 *	Scenario:
 *	Wait for connection, then spawn a new job loaded with RSHSRV,
 *	NLI with the CJ%LWP (BU -- login without password).
 */

# include "pcc:stdio.h"
# include "pcc:tops20.h"
# include "pcc:mon_files.h"
# include "pcc:mon_fork.h"
# include "mon_crjob.h"

main() {
    int jfn;

    epcap(FHslf,-1);			/* wheel up */

    for( ; ; ) {
	jfn = srvjfn();			/* wait for connect */
	if( jfn < 0 ) {
	    perror("could not get jfn");
	    exit(1);
	} /* could not open server */
	worker(jfn);
    } /* forever */
} /* main */

worker(jfn)
int jfn;
{
    char foreign[30];
    int host, sock;

    if( (sock = get_fsock(jfn)) > 1023 || (host = get_fhost(jfn)) < 0 ||
      hostname(foreign, host) < 0 )
	return( punt(jfn,"Permission denied.") );

    printf("RSHD: contact from %s, port %d\n", foreign, sock);
    if( makjob(jfn, "SYSTEM:RSHSRV.EXE") < 0 )
	printf("could not create job");

} /* worker */

/*
 *	jfn	jfn of TCP: connection
 *	prog	name of .EXE file or NULL
 */

int makjob(jfn, prog)
char *prog;
int jfn;
{
    int tvt, job;
    int crjblk[015], acs[5];
    register int i;

    for( i = 0; i < sizeof( crjblk ); i++ )
	crjblk[i] = 0;

    /* wait 'till attached, load file, give my caps, login w/o password */
    ac1 = Value(CJ_wta) | Value(CJ_fil) | Value(CJ_cap) | Value(CJ_lwp);
    ac2 = (int) crjblk;

    crjblk[CJfil] = POINT(prog);	/* BP to program to load */
    crjblk[CJtty] = NUlio;		/* new job is detached */

    if( JSYS(JScrjob,acs) == JSerr )
	return( punt(jfn, "Could not create job") );
    job = ac1;				/* save job number */

    tvt = maktvt(jfn);			/* convert jfn to tvt */
    if( tvt < 0 ) {
	logout(job);			/* could not create TVT, kill job */
	return( punt(jfn, "Could not create net virtual terminal") );
    } /* maktvt failed */

    ac1 = job | (0100000 << 18);	/* AT%TRM */
    ac2 = 0;
    ac3 = 0;
    ac4 = tvt;
    if( JSYS(JSatach,acs) == JSerr ) {	/* attach job to terminal */
	ac1 = job;			/* failed!! */
	JSYS(JSlgout,acs);		/* blast job */
	return( -1 );			/* no way to send error text!! */
    } /* atach failed */
    return( job );
} /* makjob */

int maktvt(jfn)
int jfn;
{
    int nvtdes, acs[5];

    acs[1] = jfn;
    if( JSYS(JSatnvt,acs) == JSerr )
	return( -1 );

    nvtdes = acs[1];
    if( JSYS(JSrfmod,acs) == JSerr )
	return( nvtdes );
    acs[2] |= 040000<<18;		/* set TT%LCA */
    JSYS(JSstpar,acs);

    acs[1] = nvtdes;
    acs[2] = 031;		/* .MOSLW - set width */
    acs[3] = 0;			/* to zero */
    JSYS(JSmtopr,acs);
    return( nvtdes );
}

int get_fsocket(jfn)
int jfn;
{
    int acs[5];

    ac1 = jfn;
    if( JSYS(JSgdsts,acs) == JSerr )
	return( 0377777777777 );	/* +INF as local socket */
    else
	return( ac4 );
} /* get_fsocket */

int get_fhost(jfn)
int jfn;
{
    int acs[5];

    ac1 = jfn;
    if( JSYS(JSgdsts,acs) == JSerr )
	return( -1 );
    else
	return( ac3 );
} /* get_fhost */

int srvjfn() {
    return( trytcp( "TCP:514\026#;CONNECT:PASSIVE" ) );
} /* srvjfn */


/** Local Modes: * */
/** Comment Column:40 * */
/** End: * */