freebsd-dev/lib/libutil/_secure_path.c

73 lines
2.3 KiB
C

/*-
* Based on code copyright (c) 1995,1997 by
* Berkeley Software Design, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, is permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice immediately at the beginning of the file, without modification,
* 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. This work was done expressly for inclusion into FreeBSD. Other use
* is permitted provided this notation is included.
* 4. Absolutely no warranty of function or purpose is made by the authors.
* 5. Modifications may be freely made to this file providing the above
* conditions are met.
*
* $Id: _secure_path.c,v 1.1 1997/05/10 18:55:37 davidn Exp $
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <syslog.h>
#include <errno.h>
#include <libutil.h>
/*
* Check for common security problems on a given path
* It must be:
* 1. A regular file, and exists
* 2. Owned and writaable only by root (or given owner)
* 3. Group ownership is given group or is non-group writable
*
* Returns: -2 if file does not exist,
* -1 if security test failure
* 0 otherwise
*/
int
_secure_path(const char *path, uid_t uid, gid_t gid)
{
int r = -1;
struct stat sb;
const char *msg = NULL;
if (lstat(path, &sb) < 0) {
if (errno == ENOENT) /* special case */
r = -2; /* if it is just missing, skip the log entry */
else
msg = "%s: cannot stat %s: %m";
}
else if (!S_ISREG(sb.st_mode))
msg = "%s: %s is not a regular file";
else if (sb.st_mode & S_IWOTH)
msg = "%s: %s is world writable";
else if (uid != -1 && sb.st_uid != uid && sb.st_uid != 0) {
if (uid == 0)
msg = "%s: %s is not owned by root";
else
msg = "%s: %s is not owned by uid %d";
} else if (gid != -1 && sb.st_gid != gid && (sb.st_mode & S_IWGRP))
msg = "%s: %s is group writeable by non-authorised groups";
else
r = 0;
if (msg != NULL)
syslog(LOG_ERR, msg, "_secure_path", path, uid);
return r;
}