1 files changed, 131 insertions, 0 deletions
diff --git a/src/dsa.cpp b/src/dsa.cpp
new file mode 100644
index 000000000..d3fc9107a
--- /dev/null
+++ b/src/dsa.cpp
@@ -0,0 +1,131 @@
+/*************************************************
+* DSA Source File                                *
+* (C) 1999-2006 The Botan Project                *
+*************************************************/
+
+#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);
+   check_loaded_public();
+   }
+
+/*************************************************
+* 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(const DL_Group& grp)
+   {
+   group = grp;
+   x = random_integer(2, group_q() - 1);
+
+   PKCS8_load_hook();
+   check_generated_private();
+   }
+
+/*************************************************
+* DSA_PrivateKey Constructor                     *
+*************************************************/
+DSA_PrivateKey::DSA_PrivateKey(const DL_Group& grp, const BigInt& x1,
+                               const BigInt& y1)
+   {
+   group = grp;
+   y = y1;
+   x = x1;
+
+   PKCS8_load_hook();
+   check_loaded_private();
+   }
+
+/*************************************************
+* Algorithm Specific PKCS #8 Initialization Code *
+*************************************************/
+void DSA_PrivateKey::PKCS8_load_hook()
+   {
+   if(y == 0)
+      y = power_mod(group_g(), x, group_p());
+   core = DSA_Core(group, y, x);
+   }
+
+/*************************************************
+* DSA Signature Operation                        *
+*************************************************/
+SecureVector<byte> DSA_PrivateKey::sign(const byte in[], u32bit length) const
+   {
+   const BigInt& q = group_q();
+
+   BigInt k;
+   do
+      k.randomize(q.bits());
+   while(k >= q);
+
+   return core.sign(in, length, k);
+   }
+
+/*************************************************
+* Check Private DSA Parameters                   *
+*************************************************/
+bool DSA_PrivateKey::check_key(bool strong) const
+   {
+   if(!DL_Scheme_PrivateKey::check_key(strong) || x >= group_q())
+      return false;
+
+   if(!strong)
+      return true;
+
+   try {
+      KeyPair::check_key(get_pk_signer(*this, "EMSA1(SHA-1)"),
+                         get_pk_verifier(*this, "EMSA1(SHA-1)")
+         );
+      }
+   catch(Self_Test_Failure)
+      {
+      return false;
+      }
+
+   return true;
+   }
+
+}