/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/*        All Rights Reserved   */

/*
 *      logs attempts by unknown remote machines to run uucico in FOREIGN
 *      ("/var/uucp/.Admin/Foreign").  if anything goes wrong,
 *      sends mail to login MAILTO ("uucp").  the executable should be
 *      placed in /usr/lib/uucp/remote.unknown, and should run setuid-uucp.
 */

#include        <stdio.h>
#include        <sys/types.h>
#include        <time.h>
#include        <errno.h>
#include        "uucp.h"

#define FOREIGN "/var/uucp/.Admin/Foreign"
#define MAILTO  "uucp"
#define LOGLEN  256

void fall_on_sword();

int
main(argc, argv)
int     argc;
char    *argv[];
{
        char            buf[LOGLEN], *ctoday, *logname, tmpbuf[MAXBASENAME+1];
        FILE            *fp;
        time_t          today;
        extern char     *ctime();
        extern FILE     *fopen();

        if ( argc != 2 ) {
                (void) fprintf(stderr, "USAGE: %s remotename\n", argv[0]);
                exit(101);
        }

        if ( time(&today) != -1 ) {
                ctoday = ctime(&today);
                *(ctoday + strlen(ctoday) - 1) = '\0';  /* no ending \n */
        } else
                ctoday = "NO DATE";

        logname = cuserid((char *) NULL);
        (void) strncpy(tmpbuf, argv[1], MAXBASENAME);
        tmpbuf[MAXBASENAME] = '\0';
        (void) snprintf(buf, sizeof(buf), "%s: call from system %s login %s\n",
                ctoday, tmpbuf, (logname == NULL ? "<unknown>" : logname));

        errno = 0;
        if ( (fp = fopen(FOREIGN, "a+")) == (FILE *)NULL )
                fall_on_sword("cannot open", buf);
        if ( fputs(buf, fp) == EOF )
                fall_on_sword("cannot write", buf);
        if ( fclose(fp) != 0 )
                fall_on_sword("cannot close", buf);

        return (0);
}

/* don't return from here */
void
fall_on_sword(errmsg, logmsg)
char    *errmsg, *logmsg;
{
        char            ebuf[BUFSIZ+1];
        int             fds[2];
        size_t          sz;

        (void) snprintf(ebuf, BUFSIZ,
                "To: %s\nSubject: %s %s\n\n%s %s:\t%s (%d)\nlog msg:\t%s",
                MAILTO, errmsg, FOREIGN, errmsg, FOREIGN,
                strerror(errno), errno, logmsg);
        sz = strlen(ebuf);
        if (ebuf[sz-1] != '\n') {
                ebuf[sz] = '\n';
                ebuf[sz+1] = '\0';
        }

        /* reset to real uid. get a pipe. put error message on  */
        /* "write end" of pipe, close it. dup "read end" to     */
        /* stdin and then execl mail (which will read the error */
        /* message we just wrote).                              */

        if ( setuid(getuid()) == -1 || pipe(fds) != 0
        || write(fds[1], ebuf, strlen(ebuf)) != strlen(ebuf)
        || close(fds[1]) != 0 )
                exit(errno);

        if ( fds[0] != 0 ) {
                close(0);
                if ( dup(fds[0]) != 0 )
                        exit(errno);
        }

        execl("/usr/bin/mail", "mail", MAILTO, (char *) 0);
        exit(errno);    /* shouldn't get here */
}