Add ISO9796-2 Signature Schemes giving message recovery 2 and 3.

1 files changed, 94 insertions, 0 deletions

diff --git a/src/lib/pk_pad/iso9796/iso9796.h b/src/lib/pk_pad/iso9796/iso9796.h
new file mode 100644
index 000000000..73c6d5236
--- /dev/null
+++ b/src/lib/pk_pad/iso9796/iso9796.h
@@ -0,0 +1,94 @@
+/*
+ * ISO-9796-2 - Digital signature schemes giving message recovery schemes 2 and 3
+ * (C) 2016 Tobias Niemann, Hackmanit GmbH
+ *
+ * Botan is released under the Simplified BSD License (see license.txt)
+ */
+
+#ifndef ISO9796_H
+#define ISO9796_H
+
+#include <botan/emsa.h>
+#include <botan/hash.h>
+
+namespace Botan {
+
+/**
+* ISO-9796-2 - Digital signature scheme 2 (probabilistic)
+*/
+class BOTAN_DLL ISO_9796_DS2 final : public EMSA
+   {
+   public:
+      /**
+       * @param hash function to use
+       * @param use implicit ISO trailer
+       */
+      explicit ISO_9796_DS2(HashFunction* hash, bool implicit = false) : m_hash(hash), m_implicit(implicit),
+         m_SALT_SIZE(hash->output_length()) {}
+
+      /**
+       * @param hash function to use
+       * @param whether or not the trailer is implicit
+       * @param size of the salt to use in bytes
+       */
+      ISO_9796_DS2(HashFunction* hash, bool implicit, size_t salt_size) : m_hash(hash), m_implicit(implicit),
+         m_SALT_SIZE(salt_size) {}
+
+      EMSA* clone() override
+         {return new ISO_9796_DS2(m_hash->clone(), m_implicit, m_SALT_SIZE);}
+   private:
+      void update(const byte input[], size_t length) override;
+
+      secure_vector<byte> raw_data() override;
+
+      secure_vector<byte> encoding_of(const secure_vector<byte>& msg,
+                                      size_t output_bits,
+                                      RandomNumberGenerator& rng) override;
+
+      bool verify(const secure_vector<byte>& coded,
+                  const secure_vector<byte>& raw,
+                  size_t key_bits) override;
+
+      std::unique_ptr<HashFunction> m_hash;
+      bool m_implicit;
+      size_t m_SALT_SIZE;
+      secure_vector<byte> m_msg_buffer;
+   };
+
+/**
+* ISO-9796-2 - Digital signature scheme 3 (deterministic)
+*/
+class BOTAN_DLL ISO_9796_DS3 final : public EMSA
+   {
+   public:
+      /**
+       * @param hash function to use
+       * @param whether or not the trailer is implicit
+       */
+      ISO_9796_DS3(HashFunction* hash, bool implicit = false) : m_hash(hash), m_implicit(implicit)
+         {}
+
+      EMSA* clone() override
+         {return new ISO_9796_DS3(m_hash->clone(), m_implicit);}
+   private:
+      void update(const byte input[], size_t length) override;
+
+      secure_vector<byte> raw_data() override;
+
+      secure_vector<byte> encoding_of(const secure_vector<byte>& msg,
+                                      size_t output_bits,
+                                      RandomNumberGenerator& rng) override;
+
+      bool verify(const secure_vector<byte>& coded,
+                  const secure_vector<byte>& raw,
+                  size_t key_bits) override;
+
+      std::unique_ptr<HashFunction> m_hash;
+      bool m_implicit;
+      secure_vector<byte> m_msg_buffer;
+   };
+
+}
+
+#endif
+