1 files changed, 131 insertions, 0 deletions
diff --git a/src/pubkey/dsa/dsa.cpp b/src/pubkey/dsa/dsa.cpp
new file mode 100644
index 000000000..ef69a1ee5
--- /dev/null
+++ b/src/pubkey/dsa/dsa.cpp
@@ -0,0 +1,131 @@
+/*************************************************
+* DSA Source File                                *
+* (C) 1999-2008 Jack Lloyd                       *
+*************************************************/
+
+#include <botan/dsa.h>
+#include <botan/numthry.h>
+#include <botan/keypair.h>
+
+namespace Botan {
+
+/*************************************************
+* DSA_PublicKey Constructor                      *
+*************************************************/
+DSA_PublicKey::DSA_PublicKey(const DL_Group& grp, const BigInt& y1)
+   {
+   group = grp;
+   y = y1;
+   X509_load_hook();
+   }
+
+/*************************************************
+* Algorithm Specific X.509 Initialization Code   *
+*************************************************/
+void DSA_PublicKey::X509_load_hook()
+   {
+   core = DSA_Core(group, y);
+   }
+
+/*************************************************
+* DSA Verification Function                      *
+*************************************************/
+bool DSA_PublicKey::verify(const byte msg[], u32bit msg_len,
+                           const byte sig[], u32bit sig_len) const
+   {
+   return core.verify(msg, msg_len, sig, sig_len);
+   }
+
+/*************************************************
+* Return the maximum input size in bits          *
+*************************************************/
+u32bit DSA_PublicKey::max_input_bits() const
+   {
+   return group_q().bits();
+   }
+
+/*************************************************
+* Return the size of each portion of the sig     *
+*************************************************/
+u32bit DSA_PublicKey::message_part_size() const
+   {
+   return group_q().bytes();
+   }
+
+/*************************************************
+* Create a DSA private key                       *
+*************************************************/
+DSA_PrivateKey::DSA_PrivateKey(RandomNumberGenerator& rng,
+                               const DL_Group& grp,
+                               const BigInt& x_arg)
+   {
+   group = grp;
+   x = x_arg;
+
+   if(x == 0)
+      {
+      x = BigInt::random_integer(rng, 2, group_q() - 1);
+      PKCS8_load_hook(rng, true);
+      }
+   else
+      PKCS8_load_hook(rng, false);
+   }
+
+/*************************************************
+* Algorithm Specific PKCS #8 Initialization Code *
+*************************************************/
+void DSA_PrivateKey::PKCS8_load_hook(RandomNumberGenerator& rng,
+                                     bool generated)
+   {
+   y = power_mod(group_g(), x, group_p());
+   core = DSA_Core(group, y, x);
+
+   if(generated)
+      gen_check(rng);
+   else
+      load_check(rng);
+   }
+
+/*************************************************
+* DSA Signature Operation                        *
+*************************************************/
+SecureVector<byte> DSA_PrivateKey::sign(const byte in[], u32bit length,
+                                        RandomNumberGenerator& rng) const
+   {
+   const BigInt& q = group_q();
+
+   BigInt k;
+   do
+      k.randomize(rng, q.bits());
+   while(k >= q);
+
+   return core.sign(in, length, k);
+   }
+
+/*************************************************
+* Check Private DSA Parameters                   *
+*************************************************/
+bool DSA_PrivateKey::check_key(RandomNumberGenerator& rng, bool strong) const
+   {
+   if(!DL_Scheme_PrivateKey::check_key(rng, strong) || x >= group_q())
+      return false;
+
+   if(!strong)
+      return true;
+
+   try
+      {
+      KeyPair::check_key(rng,
+                         get_pk_signer(*this, "EMSA1(SHA-1)"),
+                         get_pk_verifier(*this, "EMSA1(SHA-1)")
+         );
+      }
+   catch(Self_Test_Failure)
+      {
+      return false;
+      }
+
+   return true;
+   }
+
+}