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/*
* SPDX-FileCopyrightText: 1989 - 1994, Julianne Frances Haugh
* SPDX-FileCopyrightText: 1996 - 1998, Marek Michałkiewicz
* SPDX-FileCopyrightText: 2003 - 2005, Tomasz Kłoczko
* SPDX-FileCopyrightText: 2008 , Nicolas François
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <config.h>
#ident "$Id$"
#include <sys/types.h>
#include "defines.h"
#include <stdio.h>
#include <pwd.h>
#include "prototypes.h"
#include "shadowlog_internal.h"
#define NFIELDS 7
/*
* sgetpwent - convert a string to a (struct passwd)
*
* sgetpwent() parses a string into the parts required for a password
* structure. Strict checking is made for the UID and GID fields and
* presence of the correct number of colons. Any failing tests result
* in a NULL pointer being returned.
*
* NOTE: This function uses hard-coded string scanning functions for
* performance reasons. I am going to come up with some conditional
* compilation glarp to improve on this in the future.
*/
struct passwd *sgetpwent (const char *buf)
{
static struct passwd pwent;
static char pwdbuf[PASSWD_ENTRY_MAX_LENGTH];
int i;
char *cp;
char *fields[NFIELDS];
/*
* Copy the string to a static buffer so the pointers into
* the password structure remain valid.
*/
if (strlen (buf) >= sizeof pwdbuf) {
fprintf (shadow_logfd,
"%s: Too long passwd entry encountered, file corruption?\n",
shadow_progname);
return 0; /* fail if too long */
}
strcpy (pwdbuf, buf);
/*
* Save a pointer to the start of each colon separated
* field. The fields are converted into NUL terminated strings.
*/
for (cp = pwdbuf, i = 0; (i < NFIELDS) && (NULL != cp); i++) {
fields[i] = cp;
while (('\0' != *cp) && (':' != *cp)) {
cp++;
}
if ('\0' != *cp) {
*cp = '\0';
cp++;
} else {
cp = NULL;
}
}
/* something at the end, columns over shot */
if ( cp != NULL ) {
return( NULL );
}
/*
* There must be exactly NFIELDS colon separated fields or
* the entry is invalid. Also, the UID and GID must be non-blank.
*/
if (i != NFIELDS || *fields[2] == '\0' || *fields[3] == '\0')
return NULL;
/*
* Each of the fields is converted the appropriate data type
* and the result assigned to the password structure. If the
* UID or GID does not convert to an integer value, a NULL
* pointer is returned.
*/
pwent.pw_name = fields[0];
pwent.pw_passwd = fields[1];
if (get_uid (fields[2], &pwent.pw_uid) == 0) {
return NULL;
}
if (get_gid (fields[3], &pwent.pw_gid) == 0) {
return NULL;
}
pwent.pw_gecos = fields[4];
pwent.pw_dir = fields[5];
pwent.pw_shell = fields[6];
return &pwent;
}
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