ITS#7742 New: PBKDF2 module

Signed-off-by: HAMANO Tsukasa <hamano@osstech.co.jp>

contrib/slapd-modules/passwd/pbkdf2/Makefile

+# $OpenLDAP$
+
+LDAP_SRC = ../../../..
+LDAP_BUILD = ../../../..
+LDAP_INC = -I$(LDAP_BUILD)/include -I$(LDAP_SRC)/include -I$(LDAP_SRC)/servers/slapd
+LDAP_LIB = $(LDAP_BUILD)/libraries/libldap_r/libldap_r.la \
+	$(LDAP_BUILD)/libraries/liblber/liblber.la
+
+LIBTOOL = $(LDAP_BUILD)/libtool
+CC = gcc
+OPT = -g -O2 -Wall
+#DEFS = -DSLAPD_PBKDF2_DEBUG
+
+INCS = $(LDAP_INC)
+LIBS = $(LDAP_LIB) -lcrypto
+
+PROGRAMS = pw-pbkdf2.la
+LTVER = 0:0:0
+
+#prefix=/usr/local
+prefix=`grep -e "^prefix =" $(LDAP_BUILD)/Makefile | cut -d= -f2`
+
+exec_prefix=$(prefix)
+ldap_subdir=/openldap
+
+libdir=$(exec_prefix)/lib
+libexecdir=$(exec_prefix)/libexec
+moduledir = $(libexecdir)$(ldap_subdir)
+
+.SUFFIXES: .c .o .lo
+
+.c.lo:
+	$(LIBTOOL) --mode=compile $(CC) $(OPT) $(DEFS) $(INCS) -c $<
+
+all:		$(PROGRAMS)
+
+pw-pbkdf2.la: pw-pbkdf2.lo
+	$(LIBTOOL) --mode=link $(CC) $(OPT) -version-info $(LTVER) \
+	-rpath $(moduledir) -module -o $@ $? $(LIBS)
+
+clean:
+	rm -rf *.o *.lo *.la .libs
+
+install:	$(PROGRAMS)
+	mkdir -p $(DESTDIR)$(moduledir)
+	for p in $(PROGRAMS) ; do \
+		$(LIBTOOL) --mode=install cp $$p $(DESTDIR)$(moduledir) ; \
+	done

contrib/slapd-modules/passwd/pbkdf2/README

+PBKDF2 for OpenLDAP
+=======================
+
+pw-pbkdf2.c provides support for PBKDF2 key derivation functions in
+OpenLDAP.
+
+# Requirements
+
+  * OpenSSL 1.0.0 or later
+
+# Installations
+
+    $ cd <OPENLDAP_BUILD_DIR>/contrib/slapd-modules/passwd/
+    $ git clone https://github.com/hamano/openldap-pbkdf2.git
+    $ cd openldap-pbkdf2/
+    $ make
+    # make install
+
+# Configuration
+
+In slapd.conf:
+
+    moduleload pw-pbkdf2.so
+
+You can also tell OpenLDAP to use the schemes when processing LDAP
+Password Modify Extended Operations, thanks to the password-hash
+option in slapd.conf. For example:
+
+    password-hash {PBKDF2}
+
+# Testing
+
+You can get hash to use slappasswd.
+
+    $ slappasswd -o module-load=pw-pbkdf2.la -h {PBKDF2} -s secret
+    {PBKDF2}60000$Y6ZHtTTbeUgpIbIW0QDmDA$j/aU7jFKUSbH4UobNQDm9OEIwuw
+
+A quick way to test whether it's working is to customize the rootdn and
+rootpw in slapd.conf, eg:
+
+    rootdn "cn=Manager,dc=example,dc=com"
+    rootpw {PBKDF2}60000$Y6ZHtTTbeUgpIbIW0QDmDA$j/aU7jFKUSbH4UobNQDm9OEIwuw
+
+Then to test, run something like:
+
+    $ ldapsearch -x -b "dc=example,dc=com" -D "cn=Manager,dc=example,dc=com" -w secret
+
+# Debugging
+You can specify -DSLAPD_PBKDF2_DEBUG flag for debugging.
+
+# Message Format
+
+    {PBKDF2}<Iteration>$<Adapted Base64 Salt>$<Adapted Base64 DK>
+
+# References
+
+* [RFC 2898 Password-Based Cryptography][^1]
+[^1]: http://tools.ietf.org/html/rfc2898
+
+* [PKCS #5 PBKDF2 Test Vectors][^2]
+[^2]: http://tools.ietf.org/html/draft-josefsson-pbkdf2-test-vectors-06
+
+* [RFC 2307 Using LDAP as a Network Information Service][^3]
+[^3]: http://tools.ietf.org/html/rfc2307
+
+* [Python Passlib][^4]
+[^4]: http://pythonhosted.org/passlib/
+
+* [Adapted Base64 Encoding][^5]
+[^5]: http://pythonhosted.org/passlib/lib/passlib.utils.html#passlib.utils.ab64_encode
+
+# License
+This work is part of OpenLDAP Software <http://www.openldap.org/>.
+
+Copyright 2009-2013 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>.
+
+# ACKNOWLEDGEMENT
+This work was initially developed by HAMANO Tsukasa <hamano@osstech.co.jp>

contrib/slapd-modules/passwd/pbkdf2/pw-pbkdf2.c

+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2009-2013 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>.
+ */
+/* ACKNOWLEDGEMENT:
+ * This work was initially developed by HAMANO Tsukasa <hamano@osstech.co.jp>
+ */
+
+#define _GNU_SOURCE
+
+#include "portable.h"
+#include <ac/string.h>
+#include "lber_pvt.h"
+#include "lutil.h"
+
+#include <openssl/evp.h>
+
+#define PBKDF2_SALT_SIZE 16
+#define PBKDF2_DK_SIZE   20
+#define PBKDF2_ITERATION 60000
+
+const struct berval pbkdf2scheme = BER_BVC("{PBKDF2}");
+
+/*
+ * Converting base64 string to adapted base64 string.
+ * Adapted base64 encode is identical to general base64 encode except
+ * that it uses '.' instead of '+', and omits trailing padding '=' and
+ * whitepsace.
+ * see http://pythonhosted.org/passlib/lib/passlib.utils.html
+ * This is destructive function.
+ */
+static int b64_to_ab64(char *str)
+{
+	char *p = str;
+	while(*p++){
+		if(*p == '+'){
+			*p = '.';
+		}
+		if(*p == '='){
+			*p = '\0';
+			break;
+		}
+	}
+	return 0;
+}
+
+/*
+ * Converting adapted base64 string to base64 string.
+ * dstsize will require src length + 2, due to output string have
+ * potential to append "=" or "==".
+ * return -1 if few output buffer.
+ */
+static int ab64_to_b64(char *src, char *dst, size_t dstsize){
+	int i;
+	char *p = src;
+	for(i=0; p[i] && p[i] != '$'; i++){
+		if(i >= dstsize){
+			dst[0] = '\0';
+			return -1;
+		}
+		if(p[i] == '.'){
+			dst[i] = '+';
+		}else{
+			dst[i] = p[i];
+		}
+	}
+	for(;i%4;i++){
+		if(i >= dstsize){
+			dst[0] = '\0';
+			return -1;
+		}
+		dst[i] = '=';
+	}
+	dst[i] = '\0';
+	return 0;
+}
+
+static int pbkdf2_format(
+	const struct berval *sc,
+	int iteration,
+	const struct berval *salt,
+	const struct berval *dk,
+	struct berval *msg)
+{
+
+	int rc;
+	char salt_b64[LUTIL_BASE64_ENCODE_LEN(PBKDF2_SALT_SIZE) + 1];
+	char dk_b64[LUTIL_BASE64_ENCODE_LEN(PBKDF2_DK_SIZE) + 1];
+
+	rc = lutil_b64_ntop((unsigned char *)salt->bv_val, salt->bv_len,
+						salt_b64, sizeof(salt_b64));
+	if(rc < 0){
+		return LUTIL_PASSWD_ERR;
+	}
+	b64_to_ab64(salt_b64);
+	rc = lutil_b64_ntop((unsigned char *)dk->bv_val, dk->bv_len,
+						dk_b64, sizeof(dk_b64));
+	if(rc < 0){
+		return LUTIL_PASSWD_ERR;
+	}
+	b64_to_ab64(dk_b64);
+	msg->bv_len = asprintf(&msg->bv_val, "%s%d$%s$%s",
+						   sc->bv_val, iteration,
+						   salt_b64, dk_b64);
+	if(msg->bv_len < 0){
+		return LUTIL_PASSWD_ERR;
+	}
+
+#ifdef SLAPD_PBKDF2_DEBUG
+	printf("  Output:\t%s\n", msg->bv_val);
+#endif
+	return LUTIL_PASSWD_OK;
+}
+
+static int pbkdf2_encrypt(
+	const struct berval *scheme,
+	const struct berval *passwd,
+	struct berval *msg,
+	const char **text)
+{
+	unsigned char salt_value[PBKDF2_SALT_SIZE];
+	struct berval salt;
+	unsigned char dk_value[PBKDF2_DK_SIZE];
+	struct berval dk;
+	int iteration = PBKDF2_ITERATION;
+
+	dk.bv_val = (char *)dk_value;
+	dk.bv_len = PBKDF2_DK_SIZE;
+	salt.bv_val = (char *)salt_value;
+	salt.bv_len = sizeof(salt_value);
+
+	if(lutil_entropy((unsigned char *)salt.bv_val, salt.bv_len) < 0){
+		return LUTIL_PASSWD_ERR;
+	}
+
+	if(!PKCS5_PBKDF2_HMAC_SHA1(passwd->bv_val, passwd->bv_len,
+							   (unsigned char *)salt.bv_val, salt.bv_len,
+							   iteration, PBKDF2_DK_SIZE, dk_value)){
+		return LUTIL_PASSWD_ERR;
+	}
+
+#ifdef SLAPD_PBKDF2_DEBUG
+	printf("DEBUG pbkdf2_encrypt()\n");
+	printf("  Password:\t%s\n", passwd->bv_val);
+
+	printf("  Salt:\t\t");
+	int i;
+	for(i=0; i<salt.bv_len; i++){
+		printf("%02x", salt_value[i]);
+	}
+	printf("\n");
+	printf("  Iteration:\t%d\n", iteration);
+
+	printf("  DK:\t\t");
+	for(i=0; i<PBKDF2_DK_SIZE; i++){
+		printf("%02x", dk_value[i]);
+	}
+	printf("\n");
+#endif
+
+	return pbkdf2_format(scheme, iteration, &salt, &dk, msg);
+}
+
+static int pbkdf2_check(
+	const struct berval *scheme,
+	const struct berval *passwd,
+	const struct berval *cred,
+	const char **text)
+{
+	int rc;
+	int iteration;
+
+	/* salt_value require PBKDF2_SALT_SIZE + 1 in lutil_b64_pton. */
+	unsigned char salt_value[PBKDF2_SALT_SIZE + 1];
+	char salt_b64[LUTIL_BASE64_ENCODE_LEN(PBKDF2_SALT_SIZE) + 1];
+	/* dk_value require PBKDF2_DK_SIZE + 1 in lutil_b64_pton. */
+	unsigned char dk_value[PBKDF2_DK_SIZE + 1];
+	char dk_b64[LUTIL_BASE64_ENCODE_LEN(PBKDF2_DK_SIZE) + 1];
+	unsigned char input_dk_value[PBKDF2_DK_SIZE];
+
+#ifdef SLAPD_PBKDF2_DEBUG
+	printf("DEBUG pbkdf2_check()\n");
+	printf("  Stored Value:\t%s\n", passwd->bv_val);
+	printf("  Input Cred:\t%s\n", cred->bv_val);
+#endif
+
+	iteration = atoi(passwd->bv_val);
+	if(iteration < 1){
+		return LUTIL_PASSWD_ERR;
+	}
+
+	char *ptr;
+	ptr = strchr(passwd->bv_val, '$');
+	if(!ptr){
+		return LUTIL_PASSWD_ERR;
+	}
+	ptr++; /* skip '$' */
+	rc = ab64_to_b64(ptr, salt_b64, sizeof(salt_b64));
+	if(rc < 0){
+		return LUTIL_PASSWD_ERR;
+	}
+
+	ptr = strchr(ptr, '$');
+	if(!ptr){
+		return LUTIL_PASSWD_ERR;
+	}
+	ptr++; /* skip '$' */
+	rc = ab64_to_b64(ptr, dk_b64, sizeof(dk_b64));
+	if(rc < 0){
+		return LUTIL_PASSWD_ERR;
+	}
+
+	/* The targetsize require PBKDF2_SALT_SIZE + 1 in lutil_b64_pton. */
+	rc = lutil_b64_pton(salt_b64, salt_value, PBKDF2_SALT_SIZE + 1);
+	if(rc < 0){
+		return LUTIL_PASSWD_ERR;
+	}
+
+	/* consistency check */
+	if(rc != PBKDF2_SALT_SIZE){
+		return LUTIL_PASSWD_ERR;
+	}
+
+	/* The targetsize require PBKDF2_DK_SIZE + 1 in lutil_b64_pton. */
+	rc = lutil_b64_pton(dk_b64, dk_value, PBKDF2_DK_SIZE + 1);
+	if(rc < 0){
+		return LUTIL_PASSWD_ERR;
+	}
+
+	/* consistency check */
+	if(rc != PBKDF2_DK_SIZE){
+		return LUTIL_PASSWD_ERR;
+	}
+
+	if(!PKCS5_PBKDF2_HMAC_SHA1(cred->bv_val, cred->bv_len,
+							   salt_value, PBKDF2_SALT_SIZE,
+							   iteration, PBKDF2_DK_SIZE, input_dk_value)){
+		return LUTIL_PASSWD_ERR;
+	}
+
+	rc = memcmp(dk_value, input_dk_value, PBKDF2_DK_SIZE);
+#ifdef SLAPD_PBKDF2_DEBUG
+	printf("  Iteration:\t%d\n", iteration);
+	printf("  Base64 Salt:\t%s\n", salt_b64);
+	printf("  Base64 DK:\t%s\n", dk_b64);
+	int i;
+	printf("  Stored Salt:\t");
+	for(i=0; i<PBKDF2_SALT_SIZE; i++){
+		printf("%02x", salt_value[i]);
+	}
+	printf("\n");
+
+	printf("  Stored DK:\t");
+	for(i=0; i<PBKDF2_DK_SIZE; i++){
+		printf("%02x", dk_value[i]);
+	}
+	printf("\n");
+
+	printf("  Input DK:\t");
+	for(i=0; i<PBKDF2_DK_SIZE; i++){
+		printf("%02x", input_dk_value[i]);
+	}
+	printf("\n");
+	printf("  Result:\t%d\n", rc);
+#endif
+	return rc?LUTIL_PASSWD_ERR:LUTIL_PASSWD_OK;
+}
+
+int init_module(int argc, char *argv[]) {
+	int rc;
+	rc = lutil_passwd_add((struct berval *)&pbkdf2scheme,
+						  pbkdf2_check, pbkdf2_encrypt);
+	if(!rc) return rc;
+
+	/* TODO: add {PBKDF2-SHA256} and {PBKDF2-SHA512} schemes. */
+	return rc;
+}
+
+/*
+ * Local variables:
+ * indent-tabs-mode: t
+ * tab-width: 4
+ * c-basic-offset: 4
+ * End:
+ */