sshkey: Added builder for SSHKEY RSA keys

2013-05-07 15:38:28 +02:00
parent 584d656b77
commit cc4408abcb
6 changed files with 142 additions and 1 deletions
@@ -0,0 +1,83 @@
+/*
+ * 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_builder.h"
+
+#include <bio/bio_reader.h>
+#include <utils/debug.h>
+
+/**
+ * Load a generic public key from an SSH key blob
+ */
+static sshkey_public_key_t *parse_public_key(chunk_t blob)
+{
+	bio_reader_t *reader;
+	chunk_t format;
+
+	reader = bio_reader_create(blob);
+	if (!reader->read_data32(reader, &format))
+	{
+		DBG1(DBG_LIB, "invalid key format in SSH key");
+		reader->destroy(reader);
+		return NULL;
+	}
+	if (chunk_equals(format, chunk_from_str("ssh-rsa")))
+	{
+		chunk_t n, e;
+
+		if (!reader->read_data32(reader, &e) ||
+			!reader->read_data32(reader, &n))
+		{
+			DBG1(DBG_LIB, "invalid RSA key in SSH key");
+			reader->destroy(reader);
+			return NULL;
+		}
+		reader->destroy(reader);
+		return lib->creds->create(lib->creds, CRED_PUBLIC_KEY, KEY_RSA,
+						BUILD_RSA_MODULUS, n, BUILD_RSA_PUB_EXP, e, BUILD_END);
+	}
+	DBG1(DBG_LIB, "unsupported SSH key format %.*s", (int)format.len,
+		 format.ptr);
+	reader->destroy(reader);
+	return NULL;
+}
+
+/**
+ * See header.
+ */
+sshkey_public_key_t *sshkey_public_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_SSHKEY:
+				blob = va_arg(args, chunk_t);
+				continue;
+			case BUILD_END:
+				break;
+			default:
+				return NULL;
+		}
+		break;
+	}
+	if (blob.ptr && type == KEY_ANY)
+	{
+		return parse_public_key(blob);
+	}
+	return NULL;
+}