Parse RSA private keys from PKCS#8 encoded blobs.
authorTobias Brunner <tobias@strongswan.org>
Wed, 18 Jan 2012 18:14:56 +0000 (19:14 +0100)
committerTobias Brunner <tobias@strongswan.org>
Wed, 1 Feb 2012 17:27:45 +0000 (18:27 +0100)
src/libstrongswan/plugins/pkcs8/Makefile.am
src/libstrongswan/plugins/pkcs8/pkcs8_builder.c [new file with mode: 0644]
src/libstrongswan/plugins/pkcs8/pkcs8_builder.h [new file with mode: 0644]
src/libstrongswan/plugins/pkcs8/pkcs8_plugin.c

index c840c2d..bcaf2c6 100644 (file)
@@ -10,6 +10,7 @@ plugin_LTLIBRARIES = libstrongswan-pkcs8.la
 endif
 
 libstrongswan_pkcs8_la_SOURCES = \
-       pkcs8_plugin.h pkcs8_plugin.c
+       pkcs8_plugin.h pkcs8_plugin.c \
+       pkcs8_builder.h pkcs8_builder.c
 
 libstrongswan_pkcs8_la_LDFLAGS = -module -avoid-version
diff --git a/src/libstrongswan/plugins/pkcs8/pkcs8_builder.c b/src/libstrongswan/plugins/pkcs8/pkcs8_builder.c
new file mode 100644 (file)
index 0000000..f79925a
--- /dev/null
@@ -0,0 +1,111 @@
+/*
+ * Copyright (C) 2012 Tobias Brunner
+ * Hochschule fuer Technik Rapperswil
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+#include "pkcs8_builder.h"
+
+#include <debug.h>
+#include <asn1/oid.h>
+#include <asn1/asn1.h>
+#include <asn1/asn1_parser.h>
+#include <credentials/keys/private_key.h>
+
+/**
+ * ASN.1 definition of a privateKeyInfo structure
+ */
+static const asn1Object_t pkinfoObjects[] = {
+       { 0, "privateKeyInfo",                  ASN1_SEQUENCE,          ASN1_NONE       }, /* 0 */
+       { 1,   "version",                               ASN1_INTEGER,           ASN1_BODY       }, /* 1 */
+       { 1,   "privateKeyAlgorithm",   ASN1_EOC,                       ASN1_RAW        }, /* 2 */
+       { 1,   "privateKey",                    ASN1_OCTET_STRING,      ASN1_BODY       }, /* 3 */
+       { 1,   "attributes",                    ASN1_CONTEXT_C_0,       ASN1_OPT        }, /* 4 */
+       { 1,   "end opt",                               ASN1_EOC,                       ASN1_END        }, /* 5 */
+       { 0, "exit",                                    ASN1_EOC,                       ASN1_EXIT       }
+};
+#define PKINFO_PRIVATE_KEY_ALGORITHM   2
+#define PKINFO_PRIVATE_KEY                             3
+
+/**
+ * Load a generic private key from an ASN.1 encoded blob
+ */
+static private_key_t *parse_private_key(chunk_t blob)
+{
+       asn1_parser_t *parser;
+       chunk_t object;
+       int objectID;
+       private_key_t *key = NULL;
+       key_type_t type = KEY_ANY;
+
+       parser = asn1_parser_create(pkinfoObjects, blob);
+       parser->set_flags(parser, FALSE, TRUE);
+
+       while (parser->iterate(parser, &objectID, &object))
+       {
+               switch (objectID)
+               {
+                       case PKINFO_PRIVATE_KEY_ALGORITHM:
+                       {
+                               int oid = asn1_parse_algorithmIdentifier(object,
+                                                                               parser->get_level(parser) + 1, NULL);
+
+                               if (oid == OID_RSA_ENCRYPTION)
+                               {
+                                       type = KEY_RSA;
+                               }
+                               else
+                               {       /* key type not supported */
+                                       goto end;
+                               }
+                               break;
+                       }
+                       case PKINFO_PRIVATE_KEY:
+                       {
+                               DBG2(DBG_ASN, "-- > --");
+                               key = lib->creds->create(lib->creds, CRED_PRIVATE_KEY, type,
+                                                                                BUILD_BLOB_ASN1_DER, object, BUILD_END);
+                               DBG2(DBG_ASN, "-- < --");
+                               break;
+                       }
+               }
+       }
+
+end:
+       parser->destroy(parser);
+       return key;
+}
+
+/**
+ * See header.
+ */
+private_key_t *pkcs8_private_key_load(key_type_t type, va_list args)
+{
+       chunk_t blob = chunk_empty;
+
+       while (TRUE)
+       {
+               switch (va_arg(args, builder_part_t))
+               {
+                       case BUILD_BLOB_ASN1_DER:
+                               blob = va_arg(args, chunk_t);
+                               continue;
+                       case BUILD_END:
+                               break;
+                       default:
+                               return NULL;
+               }
+               break;
+       }
+       return parse_private_key(blob);
+}
+
diff --git a/src/libstrongswan/plugins/pkcs8/pkcs8_builder.h b/src/libstrongswan/plugins/pkcs8/pkcs8_builder.h
new file mode 100644 (file)
index 0000000..31965fa
--- /dev/null
@@ -0,0 +1,36 @@
+/*
+ * Copyright (C) 2012 Tobias Brunner
+ * Hochschule fuer Technik Rapperswil
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+/**
+ * @defgroup pkcs8_builder pkcs8_builder
+ * @{ @ingroup pkcs8
+ */
+
+#ifndef PKCS8_BUILDER_H_
+#define PKCS8_BUILDER_H_
+
+#include <credentials/builder.h>
+#include <credentials/keys/private_key.h>
+
+/**
+ * Load an RSA private key from PKCS#8 data.
+ *
+ * @param type         type of the key, KEY_RSA
+ * @param args         builder_part_t argument list
+ * @return                     private key, NULL on failure
+ */
+private_key_t *pkcs8_private_key_load(key_type_t type, va_list args);
+
+#endif /** PKCS8_BUILDER_H_ @}*/
index 8b4ec87..433da09 100644 (file)
@@ -42,6 +42,8 @@ METHOD(plugin_t, get_features, int,
        private_pkcs8_plugin_t *this, plugin_feature_t *features[])
 {
        static plugin_feature_t f[] = {
+               PLUGIN_REGISTER(PRIVKEY, pkcs8_private_key_load, FALSE),
+                       PLUGIN_PROVIDE(PRIVKEY, KEY_RSA),
        };
        *features = f;
        return countof(f);