1 files changed, 163 insertions, 0 deletions
diff --git a/src/rsa-pss.cpp b/src/rsa-pss.cpp
new file mode 100644
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--- /dev/null
+++ b/src/rsa-pss.cpp
@@ -0,0 +1,163 @@
+/*
+ * Copyright (c) 2015-2016, Avionic Design GmbH
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *  * Neither the name of Avionic Design GmbH nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#include <iostream>
+using std::cout;
+using std::cerr;
+using std::endl;
+
+#include <iomanip>
+using std::hex;
+
+#include <string>
+using std::string;
+
+#include <cstdlib>
+using std::exit;
+
+#include "cryptlib.h"
+using CryptoPP::Exception;
+
+#include "integer.h"
+using CryptoPP::Integer;
+
+#include "files.h"
+using CryptoPP::FileSource;
+
+#include "filters.h"
+using CryptoPP::StringSink;
+using CryptoPP::SignerFilter;
+
+#include "queue.h"
+using CryptoPP::ByteQueue;
+
+#include "rsa.h"
+using CryptoPP::RSA;
+using CryptoPP::RSASS;
+
+#include "pssr.h"
+using CryptoPP::PSS;
+
+#include "sha.h"
+using CryptoPP::SHA256;
+
+#include "secblock.h"
+using CryptoPP::SecByteBlock;
+
+#include "osrng.h"
+using CryptoPP::AutoSeededRandomPool;
+
+#include "rsa-pss.h"
+#include <stdexcept>
+#include "rcm.h"
+
+extern "C" int rsa_pss_sign(const char *key_file, const unsigned char *msg,
+			int len, unsigned char *sig_buf, unsigned char *modulus_buf)
+{
+	try {
+		AutoSeededRandomPool rng;
+		FileSource file(key_file, true);
+		RSA::PrivateKey key;
+		ByteQueue bq;
+
+		// Load the key
+		file.TransferTo(bq);
+		bq.MessageEnd();
+		key.BERDecodePrivateKey(bq, false, bq.MaxRetrievable());
+
+		// Write the modulus
+		Integer mod = key.GetModulus();
+		// error check
+		if (mod.ByteCount() != RCM_RSA_MODULUS_SIZE)
+			throw std::length_error("incorrect rsa key modulus length");
+		for (int i = 0; i < mod.ByteCount(); i++)
+			modulus_buf[i] = mod.GetByte(i);
+
+		// Sign the message
+		RSASS<PSS, SHA256>::Signer signer(key);
+		size_t length = signer.MaxSignatureLength();
+		SecByteBlock signature(length);
+
+		length = signer.SignMessage(rng, msg, len, signature);
+
+		// Copy in reverse order
+		for (int i = 0; i < length; i++)
+			sig_buf[length - i - 1] = signature[i];
+	}
+	catch(const CryptoPP::Exception& e) {
+		cerr << e.what() << endl;
+		return 1;
+	}
+	catch(std::length_error& le) {
+		cerr << "Error: " << le.what() << endl;
+		return 1;
+	}
+
+	return 0;
+}
+
+extern "C" int rsa_pss_sign_file(const char *key_file, const char *msg_file,
+			unsigned char *sig_buf)
+{
+	try {
+		AutoSeededRandomPool rng;
+		FileSource file(key_file, true);
+		RSA::PrivateKey key;
+		ByteQueue bq;
+
+		// Load the key
+		file.TransferTo(bq);
+		bq.MessageEnd();
+		key.BERDecodePrivateKey(bq, false, bq.MaxRetrievable());
+
+		// Sign the message
+		RSASS<PSS, SHA256>::Signer signer(key);
+		string signature;
+		FileSource src(msg_file, true,
+			new SignerFilter(rng, signer,
+					new StringSink(signature)));
+		int length = signature.length();
+		// error check
+		if (length != RCM_RSA_SIG_SIZE)
+			throw std::length_error("incorrect rsa key length");
+
+		// Copy in reverse order
+		for (int i = 0; i < length; i++)
+			sig_buf[length - i - 1] = signature[i];
+	}
+	catch(const CryptoPP::Exception& e) {
+		cerr << e.what() << endl;
+		return 1;
+	}
+	catch(std::length_error& le) {
+		cerr << "Error: " << le.what() << endl;
+		return 1;
+	}
+
+	return 0;
+}