Imported Upstream version 5.1.0

1 files changed, 153 insertions, 0 deletions

diff --git a/src/libstrongswan/plugins/sshkey/sshkey_builder.c b/src/libstrongswan/plugins/sshkey/sshkey_builder.c
new file mode 100644
index 000000000..d6a7c645a
--- /dev/null
+++ b/src/libstrongswan/plugins/sshkey/sshkey_builder.c
@@ -0,0 +1,153 @@
+/*
+ * 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 <asn1/oid.h>
+#include <asn1/asn1.h>
+#include <bio/bio_reader.h>
+#include <utils/debug.h>
+
+#define ECDSA_PREFIX "ecdsa-sha2-"
+
+/**
+ * Parse an EC domain parameter identifier as defined in RFC 5656
+ */
+static chunk_t parse_ec_identifier(chunk_t identifier)
+{
+	chunk_t oid = chunk_empty;
+
+	if (chunk_equals(identifier, chunk_from_str("nistp256")))
+	{
+		oid = asn1_build_known_oid(OID_PRIME256V1);
+	}
+	else if (chunk_equals(identifier, chunk_from_str("nistp384")))
+	{
+		oid = asn1_build_known_oid(OID_SECT384R1);
+	}
+	else if (chunk_equals(identifier, chunk_from_str("nistp521")))
+	{
+		oid = asn1_build_known_oid(OID_SECT521R1);
+	}
+	else
+	{
+		char ascii[64];
+
+		if (snprintf(ascii, sizeof(ascii), "%.*s", (int)identifier.len,
+					 identifier.ptr) < sizeof(ascii))
+		{
+			oid = asn1_wrap(ASN1_OID, "m", asn1_oid_from_string(ascii));
+		}
+	}
+	return oid;
+}
+
+/**
+ * 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);
+	}
+	else if (format.len > strlen(ECDSA_PREFIX) &&
+			 strpfx(format.ptr, ECDSA_PREFIX))
+	{
+		chunk_t ec_blob, identifier, q, oid, encoded;
+		sshkey_public_key_t *key;
+
+		ec_blob = reader->peek(reader);
+		reader->destroy(reader);
+		reader = bio_reader_create(ec_blob);
+		if (!reader->read_data32(reader, &identifier) ||
+			!reader->read_data32(reader, &q))
+		{
+			DBG1(DBG_LIB, "invalid ECDSA key in SSH key");
+			reader->destroy(reader);
+			return NULL;
+		}
+		oid = parse_ec_identifier(identifier);
+		if (!oid.ptr)
+		{
+			DBG1(DBG_LIB, "invalid ECDSA key identifier in SSH key");
+			reader->destroy(reader);
+			return NULL;
+		}
+		reader->destroy(reader);
+		/* build key from subjectPublicKeyInfo */
+		encoded = asn1_wrap(ASN1_SEQUENCE, "mm",
+						asn1_wrap(ASN1_SEQUENCE, "mm",
+							asn1_build_known_oid(OID_EC_PUBLICKEY), oid),
+						asn1_bitstring("c", q));
+		key = lib->creds->create(lib->creds, CRED_PUBLIC_KEY,
+							KEY_ECDSA, BUILD_BLOB_ASN1_DER, encoded, BUILD_END);
+		chunk_free(&encoded);
+		return key;
+	}
+	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;
+}