add (basic) support for {RADIUS} scheme; userPassword attributes prefixed with...

add (basic) support for {RADIUS} scheme; userPassword attributes prefixed with {RADIUS} are interpreted as RADIUS userids and authentication occurs contacting the configured RADIUS servers with that userid and the provided password (experimental; please report)

contrib/slapd-modules/passwd/README

@@ -6,7 +6,7 @@ Public License.
 
 This directory contains native slapd plugins for password mechanisms that
 are not actively supported by the project. Currently this includes the
-Kerberos and Netscape MTA-MD5 password mechanisms.
+Kerberos, Netscape MTA-MD5 and RADIUS password mechanisms.
 
 To use the Kerberos plugin, add:
 
@@ -20,6 +20,15 @@ moduleload pw-netscape.so
 
 to your slapd configuration file.
 
+To use the RADIUS plugin, add:
+
+moduleload pw-radius.so
+
+to your slapd configuration file; optionally, the path to a configuration
+file can be appended in the form
+
+moduleload pw-radius.so config="/etc/radius.conf"
+
 No Makefile is provided. Use a command line similar to:
 
 gcc -shared -I../../../include -Wall -g -DHAVE_KRB5 -o pw-kerberos.so kerberos.c
@@ -32,3 +41,10 @@ The corresponding command for the Netscape plugin would be:
 
 gcc -shared -I../../../include -Wall -g -o pw-netscape.so netscape.c
 
+The corresponding command for the RADIUS plugin would be:
+
+gcc -shared -I../../../include -Wall -g -o pw-radius.so radius.c -lradius
+
+(Actually, you might want to statically link the RADIUS client library 
+libradius.a into the module).
+

contrib/slapd-modules/passwd/radius.c

+/* $OpenLDAP$ */
+/*
+ * Copyright 1998-2006 The OpenLDAP Foundation.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted only as authorized by the OpenLDAP
+ * Public License.
+ *
+ * A copy of this license is available in the file LICENSE in the
+ * top-level directory of the distribution or, alternatively, at
+ * <http://www.OpenLDAP.org/license.html>.
+ */
+
+#include <stdio.h>
+
+#include <lber.h>
+#include <lber_pvt.h>	/* BER_BVC definition */
+#include "lutil.h"
+#include <ac/string.h>
+#include <ac/unistd.h>
+
+#include <radlib.h>
+
+static LUTIL_PASSWD_CHK_FUNC chk_radius;
+static const struct berval scheme = BER_BVC("{RADIUS}");
+static char *config_filename;
+
+static int
+chk_radius(
+	const struct berval	*sc,
+	const struct berval	*passwd,
+	const struct berval	*cred,
+	const char		**text )
+{
+	unsigned int		i;
+	int			rc = LUTIL_PASSWD_ERR;
+
+	struct rad_handle	*h = NULL;
+
+	for ( i = 0; i < cred->bv_len; i++ ) {
+		if ( cred->bv_val[ i ] == '\0' ) {
+			return LUTIL_PASSWD_ERR;	/* NUL character in cred */
+		}
+	}
+
+	if ( cred->bv_val[ i ] != '\0' ) {
+		return LUTIL_PASSWD_ERR;	/* cred must behave like a string */
+	}
+
+	for ( i = 0; i < passwd->bv_len; i++ ) {
+		if ( passwd->bv_val[ i ] == '\0' ) {
+			return LUTIL_PASSWD_ERR;	/* NUL character in password */
+		}
+	}
+
+	if ( passwd->bv_val[ i ] != '\0' ) {
+		return LUTIL_PASSWD_ERR;	/* passwd must behave like a string */
+	}
+
+	h = rad_auth_open();
+	if ( h == NULL ) {
+		return LUTIL_PASSWD_ERR;
+	}
+
+	if ( config_filename ) {
+		if ( rad_config( h, config_filename ) != 0 ) {
+			goto done;
+		}
+	}
+
+	if ( rad_create_request( h, RAD_ACCESS_REQUEST ) ) {
+		goto done;
+	}
+
+	if ( rad_put_string( h, RAD_USER_NAME, passwd->bv_val ) != 0 ) {
+		goto done;
+	}
+
+	if ( rad_put_string( h, RAD_USER_PASSWORD, cred->bv_val ) != 0 ) {
+		goto done;
+	}
+
+	if ( rad_send_request( h ) == RAD_ACCESS_ACCEPT ) {
+		rc = LUTIL_PASSWD_OK;
+	}
+
+done:;
+	rad_close( h );
+
+	return rc;
+}
+
+int
+init_module( int argc, char *argv[] )
+{
+	int	i;
+
+	for ( i = 0; i < argc; i++ ) {
+		if ( strncasecmp( argv[ i ], "config=", STRLENOF( "config=" ) ) == 0 ) {
+			/* FIXME: what if multiple loads of same module?
+			 * does it make sense (e.g. override an existing one)? */
+			if ( config_filename == NULL ) {
+				config_filename = ber_strdup( &argv[ i ][ STRLENOF( "config=" ) ] );
+			}
+
+		} else {
+			fprintf( stderr, "init_module(radius): unknown arg#%d=\"%s\".\n",
+				i, argv[ i ] );
+			return 1;
+		}
+	}
+
+	return lutil_passwd_add( (struct berval *)&scheme, chk_radius, NULL );
+}