sshkey: Add encoder for RSA keys

src/libstrongswan/credentials/cred_encoding.h

@@ -87,6 +87,8 @@ enum cred_encoding_type_t {
 	PRIVKEY_PGP,
 	/** DNSKEY encoding */
 	PUBKEY_DNSKEY,
+	/** SSHKEY encoding (Base64) */
+	PUBKEY_SSHKEY,
 
 	/** ASN.1 DER encoded certificate */
 	CERT_ASN1_DER,

src/libstrongswan/plugins/sshkey/Makefile.am

@@ -12,6 +12,7 @@ endif
 
 libstrongswan_sshkey_la_SOURCES = \
 	sshkey_plugin.h sshkey_plugin.c \
-	sshkey_builder.h sshkey_builder.c
+	sshkey_builder.h sshkey_builder.c \
+	sshkey_encoder.h sshkey_encoder.c
 
 libstrongswan_sshkey_la_LDFLAGS = -module -avoid-version

src/libstrongswan/plugins/sshkey/sshkey_builder.h

@@ -14,7 +14,7 @@
  */
 
 /**
- * @defgroup sshky_public_key sshky_public_key
+ * @defgroup sshkey_public_key sshkey_public_key
  * @{ @ingroup sshkey_p
  */
 

src/libstrongswan/plugins/sshkey/sshkey_encoder.c

@@ -0,0 +1,53 @@
+/*
+ * Copyright (C) 2013 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 "sshkey_encoder.h"
+
+#include <bio/bio_writer.h>
+
+/**
+ * Encode the public key as Base64 encoded SSH key blob
+ */
+static bool build_public_key(chunk_t *encoding, va_list args)
+{
+	bio_writer_t *writer;
+	chunk_t n, e;
+
+	if (cred_encoding_args(args, CRED_PART_RSA_MODULUS, &n,
+						   CRED_PART_RSA_PUB_EXP, &e, CRED_PART_END))
+	{
+		writer = bio_writer_create(0);
+		writer->write_data32(writer, chunk_from_str("ssh-rsa"));
+
+		writer->write_data32(writer, e);
+		writer->write_data32(writer, n);
+		*encoding = chunk_to_base64(writer->get_buf(writer), NULL);
+		writer->destroy(writer);
+		return TRUE;
+	}
+	return FALSE;
+}
+
+bool sshkey_encoder_encode(cred_encoding_type_t type, chunk_t *encoding,
+						   va_list args)
+{
+	switch (type)
+	{
+		case PUBKEY_SSHKEY:
+			return build_public_key(encoding, args);
+		default:
+			return FALSE;
+	}
+}

src/libstrongswan/plugins/sshkey/sshkey_encoder.h

@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2013 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 sshkey_encoder sshkey_encoder
+ * @{ @ingroup sshkey_p
+ */
+
+#ifndef SSHKEY_ENCODER_H_
+#define SSHKEY_ENCODER_H_
+
+#include <credentials/cred_encoding.h>
+
+/**
+ * Encoding of public keys to RFC 4253 format.
+ */
+bool sshkey_encoder_encode(cred_encoding_type_t type, chunk_t *encoding,
+						   va_list args);
+
+#endif /** SSHKEY_ENCODER_H_ @}*/

src/libstrongswan/plugins/sshkey/sshkey_plugin.c

@@ -17,6 +17,7 @@
 
 #include <library.h>
 #include "sshkey_builder.h"
+#include "sshkey_encoder.h"
 
 typedef struct private_sshkey_plugin_t private_sshkey_plugin_t;
 
@@ -51,6 +52,7 @@ METHOD(plugin_t, get_features, int,
 METHOD(plugin_t, destroy, void,
 	private_sshkey_plugin_t *this)
 {
+	lib->encoding->remove_encoder(lib->encoding, sshkey_encoder_encode);
 	free(this);
 }
 
@@ -70,6 +72,7 @@ plugin_t *sshkey_plugin_create()
 			},
 		},
 	);
+	lib->encoding->add_encoder(lib->encoding, sshkey_encoder_encode);
 
 	return &this->public.plugin;
 }