shadow/libmisc/hushed.c

/*
 * Copyright (c) 1991 - 1993, Julianne Frances Haugh
 * Copyright (c) 1991 - 1993, Chip Rosenthal
 * Copyright (c) 1996 - 2000, Marek Michałkiewicz
 * Copyright (c) 2003 - 2005, Tomasz Kłoczko
 * Copyright (c) 2008 - 2010, Nicolas François
 * 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.
 * 3. The name of the copyright holders or contributors may not be used to
 *    endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT
 * HOLDERS 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.
 */

#include <config.h>

#ident "$Id$"

#include <sys/types.h>
#include <stdio.h>
#include <pwd.h>
#include "defines.h"
#include "prototypes.h"
#include "getdef.h"
/*
 * hushed - determine if a user receives login messages
 *
 * Look in the hushed-logins file (or user's home directory) to see
 * if the user is to receive the login-time messages.
 */
bool hushed (const char *username)
{
	struct passwd *pw;
	const char *hushfile;
	char buf[BUFSIZ];
	bool found;
	FILE *fp;

	/*
	 * Get the name of the file to use.  If this option is not
	 * defined, default to a noisy login.
	 */

	hushfile = getdef_str ("HUSHLOGIN_FILE");
	if (NULL == hushfile) {
		return false;
	}

	pw = getpwnam (username);
	if (NULL == pw) {
		return false;
	}

	/*
	 * If this is not a fully rooted path then see if the
	 * file exists in the user's home directory.
	 */

	if (hushfile[0] != '/') {
		(void) snprintf (buf, sizeof (buf), "%s/%s", pw->pw_dir, hushfile);
		return (access (buf, F_OK) == 0);
	}

	/*
	 * If this is a fully rooted path then go through the file
	 * and see if this user, or its shell is in there.
	 */

	fp = fopen (hushfile, "r");
	if (NULL == fp) {
		return false;
	}
	for (found = false; !found && (fgets (buf, (int) sizeof buf, fp) == buf);) {
		buf[strcspn (buf, "\n")] = '\0';
		found = (strcmp (buf, pw->pw_shell) == 0) ||
		        (strcmp (buf, pw->pw_name) == 0);
	}
	(void) fclose (fp);
	return found;
}