Modularize the public key algorithms, though currently a great deal of

the underlying implementation goop remains in the core library instead of
being shunted off, due to various dependencies it has (most of which it
shouldn't).

2 files changed, 224 insertions, 0 deletions

diff --git a/src/pk/rsa/rsa.cpp b/src/pk/rsa/rsa.cpp
new file mode 100644
index 000000000..8faec9972
--- /dev/null
+++ b/src/pk/rsa/rsa.cpp
@@ -0,0 +1,161 @@
+/*************************************************
+* RSA Source File                                *
+* (C) 1999-2008 Jack Lloyd                       *
+*************************************************/
+
+#include <botan/rsa.h>
+#include <botan/numthry.h>
+#include <botan/keypair.h>
+#include <botan/parsing.h>
+
+namespace Botan {
+
+/*************************************************
+* RSA_PublicKey Constructor                      *
+*************************************************/
+RSA_PublicKey::RSA_PublicKey(const BigInt& mod, const BigInt& exp)
+   {
+   n = mod;
+   e = exp;
+   X509_load_hook();
+   }
+
+/*************************************************
+* RSA Public Operation                           *
+*************************************************/
+BigInt RSA_PublicKey::public_op(const BigInt& i) const
+   {
+   if(i >= n)
+      throw Invalid_Argument(algo_name() + "::public_op: input is too large");
+   return core.public_op(i);
+   }
+
+/*************************************************
+* RSA Encryption Function                        *
+*************************************************/
+SecureVector<byte> RSA_PublicKey::encrypt(const byte in[], u32bit len,
+                                          RandomNumberGenerator&) const
+   {
+   BigInt i(in, len);
+   return BigInt::encode_1363(public_op(i), n.bytes());
+   }
+
+/*************************************************
+* RSA Verification Function                      *
+*************************************************/
+SecureVector<byte> RSA_PublicKey::verify(const byte in[], u32bit len) const
+   {
+   BigInt i(in, len);
+   return BigInt::encode(public_op(i));
+   }
+
+/*************************************************
+* Create a RSA private key                       *
+*************************************************/
+RSA_PrivateKey::RSA_PrivateKey(RandomNumberGenerator& rng,
+                               u32bit bits, u32bit exp)
+   {
+   if(bits < 512)
+      throw Invalid_Argument(algo_name() + ": Can't make a key that is only " +
+                             to_string(bits) + " bits long");
+   if(exp < 3 || exp % 2 == 0)
+      throw Invalid_Argument(algo_name() + ": Invalid encryption exponent");
+
+   e = exp;
+   p = random_prime(rng, (bits + 1) / 2, e);
+   q = random_prime(rng, bits - p.bits(), e);
+   d = inverse_mod(e, lcm(p - 1, q - 1));
+
+   PKCS8_load_hook(rng, true);
+
+   if(n.bits() != bits)
+      throw Self_Test_Failure(algo_name() + " private key generation failed");
+   }
+
+/*************************************************
+* RSA_PrivateKey Constructor                     *
+*************************************************/
+RSA_PrivateKey::RSA_PrivateKey(RandomNumberGenerator& rng,
+                               const BigInt& prime1, const BigInt& prime2,
+                               const BigInt& exp, const BigInt& d_exp,
+                               const BigInt& mod)
+   {
+   p = prime1;
+   q = prime2;
+   e = exp;
+   d = d_exp;
+   n = mod;
+
+   if(d == 0)
+      d = inverse_mod(e, lcm(p - 1, q - 1));
+
+   PKCS8_load_hook(rng);
+   }
+
+/*************************************************
+* RSA Private Operation                          *
+*************************************************/
+BigInt RSA_PrivateKey::private_op(const byte in[], u32bit length) const
+   {
+   BigInt i(in, length);
+   if(i >= n)
+      throw Invalid_Argument(algo_name() + "::private_op: input is too large");
+
+   BigInt r = core.private_op(i);
+   if(i != public_op(r))
+      throw Self_Test_Failure(algo_name() + " private operation check failed");
+   return r;
+   }
+
+/*************************************************
+* RSA Decryption Operation                       *
+*************************************************/
+SecureVector<byte> RSA_PrivateKey::decrypt(const byte in[], u32bit len) const
+   {
+   return BigInt::encode(private_op(in, len));
+   }
+
+/*************************************************
+* RSA Signature Operation                        *
+*************************************************/
+SecureVector<byte> RSA_PrivateKey::sign(const byte in[], u32bit len,
+                                        RandomNumberGenerator&) const
+   {
+   return BigInt::encode_1363(private_op(in, len), n.bytes());
+   }
+
+/*************************************************
+* Check Private RSA Parameters                   *
+*************************************************/
+bool RSA_PrivateKey::check_key(RandomNumberGenerator& rng, bool strong) const
+   {
+   if(!IF_Scheme_PrivateKey::check_key(rng, strong))
+      return false;
+
+   if(!strong)
+      return true;
+
+   if((e * d) % lcm(p - 1, q - 1) != 1)
+      return false;
+
+   try
+      {
+      KeyPair::check_key(rng,
+                         get_pk_encryptor(*this, "EME1(SHA-1)"),
+                         get_pk_decryptor(*this, "EME1(SHA-1)")
+         );
+
+      KeyPair::check_key(rng,
+                         get_pk_signer(*this, "EMSA4(SHA-1)"),
+                         get_pk_verifier(*this, "EMSA4(SHA-1)")
+         );
+      }
+   catch(Self_Test_Failure)
+      {
+      return false;
+      }
+
+   return true;
+   }
+
+}
diff --git a/src/pk/rsa/rsa.h b/src/pk/rsa/rsa.h
new file mode 100644
index 000000000..445902a6f
--- /dev/null
+++ b/src/pk/rsa/rsa.h
@@ -0,0 +1,63 @@
+/*************************************************
+* RSA Header File                                *
+* (C) 1999-2008 Jack Lloyd                       *
+*************************************************/
+
+#ifndef BOTAN_RSA_H__
+#define BOTAN_RSA_H__
+
+#include <botan/if_algo.h>
+
+namespace Botan {
+
+/*************************************************
+* RSA Public Key                                 *
+*************************************************/
+class BOTAN_DLL RSA_PublicKey : public PK_Encrypting_Key,
+                                public PK_Verifying_with_MR_Key,
+                                public virtual IF_Scheme_PublicKey
+   {
+   public:
+      std::string algo_name() const { return "RSA"; }
+
+      SecureVector<byte> encrypt(const byte[], u32bit,
+                                 RandomNumberGenerator& rng) const;
+
+      SecureVector<byte> verify(const byte[], u32bit) const;
+
+      RSA_PublicKey() {}
+      RSA_PublicKey(const BigInt&, const BigInt&);
+   protected:
+      BigInt public_op(const BigInt&) const;
+   };
+
+/*************************************************
+* RSA Private Key                                *
+*************************************************/
+class BOTAN_DLL RSA_PrivateKey : public RSA_PublicKey,
+                                 public PK_Decrypting_Key,
+                                 public PK_Signing_Key,
+                                 public IF_Scheme_PrivateKey
+   {
+   public:
+      SecureVector<byte> sign(const byte[], u32bit,
+                              RandomNumberGenerator&) const;
+
+      SecureVector<byte> decrypt(const byte[], u32bit) const;
+
+      bool check_key(RandomNumberGenerator& rng, bool) const;
+
+      RSA_PrivateKey() {}
+
+      RSA_PrivateKey(RandomNumberGenerator&,
+                     const BigInt& p, const BigInt& q, const BigInt& e,
+                     const BigInt& d = 0, const BigInt& n = 0);
+
+      RSA_PrivateKey(RandomNumberGenerator&, u32bit bits, u32bit = 65537);
+   private:
+      BigInt private_op(const byte[], u32bit) const;
+   };
+
+}
+
+#endif