Add the CMAC constants for 256 and 512 bit block ciphers

Also add test vectors for Threefish-512 CMAC and EAX, both
generated by the library.

3 files changed, 46 insertions, 6 deletions

diff --git a/src/lib/mac/cmac/cmac.cpp b/src/lib/mac/cmac/cmac.cpp
index 16524faec..b4c9cb129 100644
--- a/src/lib/mac/cmac/cmac.cpp
+++ b/src/lib/mac/cmac/cmac.cpp
@@ -16,9 +16,7 @@ namespace Botan {
 */
 secure_vector<byte> CMAC::poly_double(const secure_vector<byte>& in)
    {
-   const byte polynomial = (in.size() == 16) ? 0x87 : 0x1B;
-
-   const byte poly_xor = (in[0] & 0x80) ? polynomial : 0;
+   const bool top_carry = (in[0] & 0x80);
 
    secure_vector<byte> out = in;
 
@@ -30,7 +28,26 @@ secure_vector<byte> CMAC::poly_double(const secure_vector<byte>& in)
       carry = (temp >> 7);
       }
 
-   out[out.size()-1] ^= poly_xor;
+   if(top_carry)
+      {
+      switch(in.size())
+         {
+         case 8:
+            out[out.size()-1] ^= 0x1B;
+            break;
+         case 16:
+            out[out.size()-1] ^= 0x87;
+            break;
+         case 32:
+            out[out.size()-2] ^= 0x4;
+            out[out.size()-1] ^= 0x25;
+            break;
+         case 64:
+            out[out.size()-2] ^= 0x1;
+            out[out.size()-1] ^= 0x25;
+            break;
+         }
+      }
 
    return out;
    }
@@ -133,8 +150,13 @@ MessageAuthenticationCode* CMAC::clone() const
 */
 CMAC::CMAC(BlockCipher* cipher) : m_cipher(cipher)
    {
-   if(m_cipher->block_size() != 8 && m_cipher->block_size() != 16)
-      throw Invalid_Argument("CMAC cannot use the cipher " + m_cipher->name());
+   if(m_cipher->block_size() !=  8 && m_cipher->block_size() != 16 &&
+      m_cipher->block_size() != 32 && m_cipher->block_size() != 64)
+      {
+      throw Invalid_Argument("CMAC cannot use the " +
+                             std::to_string(m_cipher->block_size() * 8) +
+                             " bit cipher " + m_cipher->name());
+      }
 
    m_state.resize(output_length());
    m_buffer.resize(output_length());
diff --git a/src/tests/data/aead/eax.vec b/src/tests/data/aead/eax.vec
index 90b7e2903..6b6a408a7 100644
--- a/src/tests/data/aead/eax.vec
+++ b/src/tests/data/aead/eax.vec
@@ -1458,3 +1458,12 @@ Nonce = 000102030405060708090A0B0C0D0E0F
 AD = 000102030405060708090A0B0C0D0E0F
 In = 000102030405060708090A0B0C0D0E0F
 Out = 600FA4149AF252C87B828C780AEFF8BC33D7D11DCDC19936
+
+# Threefish vectors generated by us
+
+[Threefish-512/EAX]
+Key = 2E749EE66C1E6A162E749EE66C1E6A162E749EE66C1E6A169315F0C4AF8500EB9315F0C4AF8500EB9315F0C4AF8500EBDADBCE3EE3B8FC50DADB3F8050DAEBDC
+Nonce = 000102030405060708090A0B0C0D0E0F
+AD = 000102030405060708090A0B0C0D0E0F
+In = 000102030405060708090A0B0C0D0E0F
+Out = 5E8EEADAB182F96CC0144B722F3383FBFC9F462072B9D82FE49F9AD148DA83F23CE248546FC580FAB0A01E21BCE063FF54FFB5038A3FEDD2296B535936EFDE77E51125C9F4EFC4AE073F5A98921C601F
diff --git a/src/tests/data/mac/cmac.vec b/src/tests/data/mac/cmac.vec
index 55c476294..3859d6464 100644
--- a/src/tests/data/mac/cmac.vec
+++ b/src/tests/data/mac/cmac.vec
@@ -145,3 +145,12 @@ Key = 420D2C372E496D403A9F520158FCCDA6D6BCE14E6EAD2B90918B919E5E8621A0
 In = 4DD7C1974501D1E454D23C509FE2265BC375CA
 Out = CB1C20084C5DACB3270F118633DB4F33
 
+[CMAC(Blowfish)]
+Key = 0000000000000000
+In = 0000000000000000000000000000000000000000000000000000000000000000
+Out = CE2A6A95E8C3CAB9
+
+[CMAC(Threefish-512)]
+Key = 00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
+In = 0000000000000000000000000000000000000000000000000000000000000000
+Out = C07C71A284C7A63023146376F895E83543EA3547A9268861CD00B7AC405AFC34A9EC86A30622D38C7E765521B148AAB5DEDD3AE80496ED56BCCB17B2E3D18009