shadow/lib/sgetspent.c

/*
 * SPDX-FileCopyrightText: 1989 - 1994, Julianne Frances Haugh
 * SPDX-FileCopyrightText: 1996 - 1998, Marek Michałkiewicz
 * SPDX-FileCopyrightText: 2003 - 2005, Tomasz Kłoczko
 * SPDX-FileCopyrightText: 2009       , Nicolas François
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#include <config.h>

/* Newer versions of Linux libc already have shadow support.  */
#ifndef HAVE_SGETSPENT

#ident "$Id$"

#include <stddef.h>
#include <stdio.h>
#include <sys/types.h>
#include <string.h>

#include "atoi/a2i/a2s.h"
#include "atoi/str2i/str2u.h"
#include "defines.h"
#include "prototypes.h"
#include "shadowlog_internal.h"
#include "string/strcmp/streq.h"
#include "string/strtok/stpsep.h"


#define	FIELDS	9
#define	OFIELDS	5


/*
 * sgetspent - convert string in shadow file format to (struct spwd *)
 */
struct spwd *
sgetspent(const char *string)
{
	static char spwbuf[PASSWD_ENTRY_MAX_LENGTH];
	static struct spwd spwd;
	char *fields[FIELDS];
	char *cp;
	int i;

	/*
	 * Copy string to local buffer.  It has to be tokenized and we
	 * have to do that to our private copy.
	 */

	if (strlen (string) >= sizeof spwbuf) {
		fprintf (shadow_logfd,
		         "%s: Too long passwd entry encountered, file corruption?\n",
		         shadow_progname);
		return NULL;	/* fail if too long */
	}
	strcpy (spwbuf, string);
	stpsep(spwbuf, "\n");

	/*
	 * Tokenize the string into colon separated fields.  Allow up to
	 * FIELDS different fields.
	 */

	for (cp = spwbuf, i = 0; cp != NULL && i < FIELDS; i++)
		fields[i] = strsep(&cp, ":");

	if (i == (FIELDS - 1))
		fields[i++] = "";

	if (cp != NULL || (i != FIELDS && i != OFIELDS))
		return NULL;

	/*
	 * Start populating the structure.  The fields are all in
	 * static storage, as is the structure we pass back.
	 */

	spwd.sp_namp = fields[0];
	spwd.sp_pwdp = fields[1];

	/*
	 * Get the last changed date.  For all of the integer fields,
	 * we check for proper format.  It is an error to have an
	 * incorrectly formatted number.
	 */

	if (streq(fields[2], ""))
		spwd.sp_lstchg = -1;
	else if (a2sl(&spwd.sp_lstchg, fields[2], NULL, 0, 0, LONG_MAX) == -1)
		return NULL;

	/*
	 * Get the minimum period between password changes.
	 */

	if (streq(fields[3], ""))
		spwd.sp_min = -1;
	else if (a2sl(&spwd.sp_min, fields[3], NULL, 0, 0, LONG_MAX) == -1)
		return NULL;

	/*
	 * Get the maximum number of days a password is valid.
	 */

	if (streq(fields[4], ""))
		spwd.sp_max = -1;
	else if (a2sl(&spwd.sp_max, fields[4], NULL, 0, 0, LONG_MAX) == -1)
		return NULL;

	/*
	 * If there are only OFIELDS fields (this is a SVR3.2 /etc/shadow
	 * formatted file), initialize the other field members to -1.
	 */

	if (i == OFIELDS) {
		spwd.sp_warn   = -1;
		spwd.sp_inact  = -1;
		spwd.sp_expire = -1;
		spwd.sp_flag   = SHADOW_SP_FLAG_UNSET;

		return &spwd;
	}

	/*
	 * Get the number of days of password expiry warning.
	 */

	if (streq(fields[5], ""))
		spwd.sp_warn = -1;
	else if (a2sl(&spwd.sp_warn, fields[5], NULL, 0, 0, LONG_MAX) == -1)
		return NULL;

	/*
	 * Get the number of days of inactivity before an account is
	 * disabled.
	 */

	if (streq(fields[6], ""))
		spwd.sp_inact = -1;
	else if (a2sl(&spwd.sp_inact, fields[6], NULL, 0, 0, LONG_MAX) == -1)
		return NULL;

	/*
	 * Get the number of days after the epoch before the account is
	 * set to expire.
	 */

	if (streq(fields[7], ""))
		spwd.sp_expire = -1;
	else if (a2sl(&spwd.sp_expire, fields[7], NULL, 0, 0, LONG_MAX) == -1)
		return NULL;

	/*
	 * This field is reserved for future use.  But it isn't supposed
	 * to have anything other than a valid integer in it.
	 */

	if (streq(fields[8], ""))
		spwd.sp_flag = SHADOW_SP_FLAG_UNSET;
	else if (str2ul(&spwd.sp_flag, fields[8]) == -1)
		return NULL;

	return (&spwd);
}
#else
extern int ISO_C_forbids_an_empty_translation_unit;
#endif