Move DESX into desx.h and desx.cpp

Clean up DES implementation internals.

7 files changed, 261 insertions, 201 deletions

diff --git a/src/cipher/des/des.cpp b/src/cipher/des/des.cpp
index d09752854..53a1a278e 100644
--- a/src/cipher/des/des.cpp
+++ b/src/cipher/des/des.cpp
@@ -1,129 +1,23 @@
 /*************************************************
 * DES Source File                                *
-* (C) 1999-2007 Jack Lloyd                       *
+* (C) 1999-2008 Jack Lloyd                       *
 *************************************************/
 
 #include <botan/des.h>
 #include <botan/loadstor.h>
-#include <botan/xor_buf.h>
 
 namespace Botan {
 
-/*************************************************
-* DES Encryption                                 *
-*************************************************/
-void DES::enc(const byte in[], byte out[]) const
-   {
-   u32bit L = load_be<u32bit>(in, 0), R = load_be<u32bit>(in, 1);
-
-   IP(L, R);
-   raw_encrypt(L, R);
-   FP(L, R);
-
-   store_be(out, R, L);
-   }
-
-/*************************************************
-* DES Decryption                                 *
-*************************************************/
-void DES::dec(const byte in[], byte out[]) const
-   {
-   u32bit L = load_be<u32bit>(in, 0), R = load_be<u32bit>(in, 1);
-
-   IP(L, R);
-   raw_decrypt(L, R);
-   FP(L, R);
-
-   store_be(out, R, L);
-   }
-
-/*************************************************
-* DES Initial Permutation                        *
-*************************************************/
-void DES::IP(u32bit& L, u32bit& R)
-   {
-   u64bit T = (IPTAB1[get_byte(0, L)]     ) | (IPTAB1[get_byte(1, L)] << 1) |
-              (IPTAB1[get_byte(2, L)] << 2) | (IPTAB1[get_byte(3, L)] << 3) |
-              (IPTAB1[get_byte(0, R)] << 4) | (IPTAB1[get_byte(1, R)] << 5) |
-              (IPTAB1[get_byte(2, R)] << 6) | (IPTAB2[get_byte(3, R)]     );
-   L = static_cast<u32bit>(T >> 32);
-   R = static_cast<u32bit>(T);
-   }
-
-/*************************************************
-* DES Final Permutation                          *
-*************************************************/
-void DES::FP(u32bit& L, u32bit& R)
-   {
-   u64bit T = (FPTAB1[get_byte(0, L)] << 5) | (FPTAB1[get_byte(1, L)] << 3) |
-              (FPTAB1[get_byte(2, L)] << 1) | (FPTAB2[get_byte(3, L)] << 1) |
-              (FPTAB1[get_byte(0, R)] << 4) | (FPTAB1[get_byte(1, R)] << 2) |
-              (FPTAB1[get_byte(2, R)]     ) | (FPTAB2[get_byte(3, R)]     );
-   L = static_cast<u32bit>(T >> 32);
-   R = static_cast<u32bit>(T);
-   }
-
-/*************************************************
-* DES Raw Encryption                             *
-*************************************************/
-void DES::raw_encrypt(u32bit& L, u32bit& R) const
-   {
-   for(u32bit j = 0; j != 16; j += 2)
-      {
-      u32bit T0, T1;
-
-      T0 = rotate_right(R, 4) ^ round_key[2*j];
-      T1 =              R     ^ round_key[2*j + 1];
-
-      L ^= SPBOX1[get_byte(0, T0)] ^ SPBOX2[get_byte(0, T1)] ^
-           SPBOX3[get_byte(1, T0)] ^ SPBOX4[get_byte(1, T1)] ^
-           SPBOX5[get_byte(2, T0)] ^ SPBOX6[get_byte(2, T1)] ^
-           SPBOX7[get_byte(3, T0)] ^ SPBOX8[get_byte(3, T1)];
-
-      T0 = rotate_right(L, 4) ^ round_key[2*j + 2];
-      T1 =              L     ^ round_key[2*j + 3];
-
-      R ^= SPBOX1[get_byte(0, T0)] ^ SPBOX2[get_byte(0, T1)] ^
-           SPBOX3[get_byte(1, T0)] ^ SPBOX4[get_byte(1, T1)] ^
-           SPBOX5[get_byte(2, T0)] ^ SPBOX6[get_byte(2, T1)] ^
-           SPBOX7[get_byte(3, T0)] ^ SPBOX8[get_byte(3, T1)];
-      }
-   }
-
-/*************************************************
-* DES Raw Decryption                             *
-*************************************************/
-void DES::raw_decrypt(u32bit& L, u32bit& R) const
-   {
-   for(u32bit j = 16; j != 0; j -= 2)
-      {
-      u32bit T0, T1;
-
-      T0 = rotate_right(R, 4) ^ round_key[2*j - 2];
-      T1 =              R     ^ round_key[2*j - 1];
-
-      L ^= SPBOX1[get_byte(0, T0)] ^ SPBOX2[get_byte(0, T1)] ^
-           SPBOX3[get_byte(1, T0)] ^ SPBOX4[get_byte(1, T1)] ^
-           SPBOX5[get_byte(2, T0)] ^ SPBOX6[get_byte(2, T1)] ^
-           SPBOX7[get_byte(3, T0)] ^ SPBOX8[get_byte(3, T1)];
-
-      T0 = rotate_right(L, 4) ^ round_key[2*j - 4];
-      T1 =              L     ^ round_key[2*j - 3];
-
-      R ^= SPBOX1[get_byte(0, T0)] ^ SPBOX2[get_byte(0, T1)] ^
-           SPBOX3[get_byte(1, T0)] ^ SPBOX4[get_byte(1, T1)] ^
-           SPBOX5[get_byte(2, T0)] ^ SPBOX6[get_byte(2, T1)] ^
-           SPBOX7[get_byte(3, T0)] ^ SPBOX8[get_byte(3, T1)];
-      }
-   }
+namespace {
 
 /*************************************************
 * DES Key Schedule                               *
 *************************************************/
-void DES::key(const byte key[], u32bit)
+void des_key_schedule(u32bit round_key[32], const byte key[8])
    {
    static const byte ROT[16] = { 1, 1, 2, 2, 2, 2, 2, 2,
                                  1, 2, 2, 2, 2, 2, 2, 1 };
+
    u32bit C = ((key[7] & 0x80) << 20) | ((key[6] & 0x80) << 19) |
               ((key[5] & 0x80) << 18) | ((key[4] & 0x80) << 17) |
               ((key[3] & 0x80) << 16) | ((key[2] & 0x80) << 15) |
@@ -152,6 +46,7 @@ void DES::key(const byte key[], u32bit)
               ((key[1] & 0x08) <<  2) | ((key[0] & 0x08) <<  1) |
               ((key[3] & 0x10) >>  1) | ((key[2] & 0x10) >>  2) |
               ((key[1] & 0x10) >>  3) | ((key[0] & 0x10) >>  4);
+
    for(u32bit j = 0; j != 16; ++j)
       {
       C = ((C << ROT[j]) | (C >> (28-ROT[j]))) & 0x0FFFFFFF;
@@ -182,78 +77,187 @@ void DES::key(const byte key[], u32bit)
    }
 
 /*************************************************
-* TripleDES Encryption                           *
+* DES Encryption                                 *
 *************************************************/
-void TripleDES::enc(const byte in[], byte out[]) const
+void des_encrypt(u32bit& L, u32bit& R,
+                 const u32bit round_key[32])
    {
-   u32bit L = load_be<u32bit>(in, 0), R = load_be<u32bit>(in, 1);
+   for(u32bit j = 0; j != 16; j += 2)
+      {
+      u32bit T0, T1;
 
-   DES::IP(L, R);
-   des1.raw_encrypt(L, R);
-   des2.raw_decrypt(R, L);
-   des3.raw_encrypt(L, R);
-   DES::FP(L, R);
+      T0 = rotate_right(R, 4) ^ round_key[2*j];
+      T1 =              R     ^ round_key[2*j + 1];
+
+      L ^= DES_SPBOX1[get_byte(0, T0)] ^ DES_SPBOX2[get_byte(0, T1)] ^
+           DES_SPBOX3[get_byte(1, T0)] ^ DES_SPBOX4[get_byte(1, T1)] ^
+           DES_SPBOX5[get_byte(2, T0)] ^ DES_SPBOX6[get_byte(2, T1)] ^
+           DES_SPBOX7[get_byte(3, T0)] ^ DES_SPBOX8[get_byte(3, T1)];
+
+      T0 = rotate_right(L, 4) ^ round_key[2*j + 2];
+      T1 =              L     ^ round_key[2*j + 3];
 
-   store_be(out, R, L);
+      R ^= DES_SPBOX1[get_byte(0, T0)] ^ DES_SPBOX2[get_byte(0, T1)] ^
+           DES_SPBOX3[get_byte(1, T0)] ^ DES_SPBOX4[get_byte(1, T1)] ^
+           DES_SPBOX5[get_byte(2, T0)] ^ DES_SPBOX6[get_byte(2, T1)] ^
+           DES_SPBOX7[get_byte(3, T0)] ^ DES_SPBOX8[get_byte(3, T1)];
+      }
    }
 
 /*************************************************
-* TripleDES Decryption                           *
+* DES Decryption                                 *
 *************************************************/
-void TripleDES::dec(const byte in[], byte out[]) const
+void des_decrypt(u32bit& L, u32bit& R,
+                 const u32bit round_key[32])
    {
-   u32bit L = load_be<u32bit>(in, 0), R = load_be<u32bit>(in, 1);
+   for(u32bit j = 16; j != 0; j -= 2)
+      {
+      u32bit T0, T1;
 
-   DES::IP(L, R);
-   des3.raw_decrypt(L, R);
-   des2.raw_encrypt(R, L);
-   des1.raw_decrypt(L, R);
-   DES::FP(L, R);
+      T0 = rotate_right(R, 4) ^ round_key[2*j - 2];
+      T1 =              R     ^ round_key[2*j - 1];
+
+      L ^= DES_SPBOX1[get_byte(0, T0)] ^ DES_SPBOX2[get_byte(0, T1)] ^
+           DES_SPBOX3[get_byte(1, T0)] ^ DES_SPBOX4[get_byte(1, T1)] ^
+           DES_SPBOX5[get_byte(2, T0)] ^ DES_SPBOX6[get_byte(2, T1)] ^
+           DES_SPBOX7[get_byte(3, T0)] ^ DES_SPBOX8[get_byte(3, T1)];
+
+      T0 = rotate_right(L, 4) ^ round_key[2*j - 4];
+      T1 =              L     ^ round_key[2*j - 3];
 
-   store_be(out, R, L);
+      R ^= DES_SPBOX1[get_byte(0, T0)] ^ DES_SPBOX2[get_byte(0, T1)] ^
+           DES_SPBOX3[get_byte(1, T0)] ^ DES_SPBOX4[get_byte(1, T1)] ^
+           DES_SPBOX5[get_byte(2, T0)] ^ DES_SPBOX6[get_byte(2, T1)] ^
+           DES_SPBOX7[get_byte(3, T0)] ^ DES_SPBOX8[get_byte(3, T1)];
+      }
    }
 
+}
+
 /*************************************************
-* TripleDES Key Schedule                         *
+* DES Encryption                                 *
 *************************************************/
-void TripleDES::key(const byte key[], u32bit length)
+void DES::enc(const byte in[], byte out[]) const
    {
-   des1.set_key(key, 8);
-   des2.set_key(key + 8, 8);
-   if(length == 24)
-      des3.set_key(key + 16, 8);
-   else
-      des3.set_key(key, 8);
+   u64bit T = (DES_IPTAB1[in[0]]     ) | (DES_IPTAB1[in[1]] << 1) |
+              (DES_IPTAB1[in[2]] << 2) | (DES_IPTAB1[in[3]] << 3) |
+              (DES_IPTAB1[in[4]] << 4) | (DES_IPTAB1[in[5]] << 5) |
+              (DES_IPTAB1[in[6]] << 6) | (DES_IPTAB2[in[7]]     );
+
+   u32bit L = static_cast<u32bit>(T >> 32);
+   u32bit R = static_cast<u32bit>(T);
+
+   des_encrypt(L, R, round_key);
+
+   T = (DES_FPTAB1[get_byte(0, L)] << 5) | (DES_FPTAB1[get_byte(1, L)] << 3) |
+       (DES_FPTAB1[get_byte(2, L)] << 1) | (DES_FPTAB2[get_byte(3, L)] << 1) |
+       (DES_FPTAB1[get_byte(0, R)] << 4) | (DES_FPTAB1[get_byte(1, R)] << 2) |
+       (DES_FPTAB1[get_byte(2, R)]     ) | (DES_FPTAB2[get_byte(3, R)]     );
+
+   T = rotate_left(T, 32);
+
+   store_be(T, out);
+   }
+
+/*************************************************
+* DES Decryption                                 *
+*************************************************/
+void DES::dec(const byte in[], byte out[]) const
+   {
+   u64bit T = (DES_IPTAB1[in[0]]     ) | (DES_IPTAB1[in[1]] << 1) |
+              (DES_IPTAB1[in[2]] << 2) | (DES_IPTAB1[in[3]] << 3) |
+              (DES_IPTAB1[in[4]] << 4) | (DES_IPTAB1[in[5]] << 5) |
+              (DES_IPTAB1[in[6]] << 6) | (DES_IPTAB2[in[7]]     );
+
+   u32bit L = static_cast<u32bit>(T >> 32);
+   u32bit R = static_cast<u32bit>(T);
+
+   des_decrypt(L, R, round_key);
+
+   T = (DES_FPTAB1[get_byte(0, L)] << 5) | (DES_FPTAB1[get_byte(1, L)] << 3) |
+       (DES_FPTAB1[get_byte(2, L)] << 1) | (DES_FPTAB2[get_byte(3, L)] << 1) |
+       (DES_FPTAB1[get_byte(0, R)] << 4) | (DES_FPTAB1[get_byte(1, R)] << 2) |
+       (DES_FPTAB1[get_byte(2, R)]     ) | (DES_FPTAB2[get_byte(3, R)]     );
+
+   T = rotate_left(T, 32);
+
+   store_be(T, out);
    }
 
 /*************************************************
-* DESX Encryption                                *
+* DES Key Schedule                               *
 *************************************************/
-void DESX::enc(const byte in[], byte out[]) const
+void DES::key(const byte key[], u32bit)
    {
-   xor_buf(out, in, K1.begin(), BLOCK_SIZE);
-   des.encrypt(out);
-   xor_buf(out, K2.begin(), BLOCK_SIZE);
+   des_key_schedule(round_key.begin(), key);
    }
 
 /*************************************************
-* DESX Decryption                                *
+* TripleDES Encryption                           *
 *************************************************/
-void DESX::dec(const byte in[], byte out[]) const
+void TripleDES::enc(const byte in[], byte out[]) const
    {
-   xor_buf(out, in, K2.begin(), BLOCK_SIZE);
-   des.decrypt(out);
-   xor_buf(out, K1.begin(), BLOCK_SIZE);
+   u64bit T = (DES_IPTAB1[in[0]]     ) | (DES_IPTAB1[in[1]] << 1) |
+              (DES_IPTAB1[in[2]] << 2) | (DES_IPTAB1[in[3]] << 3) |
+              (DES_IPTAB1[in[4]] << 4) | (DES_IPTAB1[in[5]] << 5) |
+              (DES_IPTAB1[in[6]] << 6) | (DES_IPTAB2[in[7]]     );
+
+   u32bit L = static_cast<u32bit>(T >> 32);
+   u32bit R = static_cast<u32bit>(T);
+
+   des_encrypt(L, R, round_key);
+   des_decrypt(R, L, round_key + 32);
+   des_encrypt(L, R, round_key + 64);
+
+   T = (DES_FPTAB1[get_byte(0, L)] << 5) | (DES_FPTAB1[get_byte(1, L)] << 3) |
+       (DES_FPTAB1[get_byte(2, L)] << 1) | (DES_FPTAB2[get_byte(3, L)] << 1) |
+       (DES_FPTAB1[get_byte(0, R)] << 4) | (DES_FPTAB1[get_byte(1, R)] << 2) |
+       (DES_FPTAB1[get_byte(2, R)]     ) | (DES_FPTAB2[get_byte(3, R)]     );
+
+   T = rotate_left(T, 32);
+
+   store_be(T, out);
    }
 
 /*************************************************
-* DESX Key Schedule                              *
+* TripleDES Decryption                           *
 *************************************************/
-void DESX::key(const byte key[], u32bit)
+void TripleDES::dec(const byte in[], byte out[]) const
    {
-   K1.copy(key, 8);
-   des.set_key(key + 8, 8);
-   K2.copy(key + 16, 8);
+   u64bit T = (DES_IPTAB1[in[0]]     ) | (DES_IPTAB1[in[1]] << 1) |
+              (DES_IPTAB1[in[2]] << 2) | (DES_IPTAB1[in[3]] << 3) |
+              (DES_IPTAB1[in[4]] << 4) | (DES_IPTAB1[in[5]] << 5) |
+              (DES_IPTAB1[in[6]] << 6) | (DES_IPTAB2[in[7]]     );
+
+   u32bit L = static_cast<u32bit>(T >> 32);
+   u32bit R = static_cast<u32bit>(T);
+
+   des_decrypt(L, R, round_key + 64);
+   des_encrypt(R, L, round_key + 32);
+   des_decrypt(L, R, round_key);
+
+   T = (DES_FPTAB1[get_byte(0, L)] << 5) | (DES_FPTAB1[get_byte(1, L)] << 3) |
+       (DES_FPTAB1[get_byte(2, L)] << 1) | (DES_FPTAB2[get_byte(3, L)] << 1) |
+       (DES_FPTAB1[get_byte(0, R)] << 4) | (DES_FPTAB1[get_byte(1, R)] << 2) |
+       (DES_FPTAB1[get_byte(2, R)]     ) | (DES_FPTAB2[get_byte(3, R)]     );
+
+   T = rotate_left(T, 32);
+
+   store_be(T, out);
+   }
+
+/*************************************************
+* TripleDES Key Schedule                         *
+*************************************************/
+void TripleDES::key(const byte key[], u32bit length)
+   {
+   des_key_schedule(&round_key[0], key);
+   des_key_schedule(&round_key[32], key + 8);
+
+   if(length == 24)
+      des_key_schedule(&round_key[64], key + 16);
+   else
+      copy_mem(&round_key[64], round_key.begin(), 32);
    }
 
 }
diff --git a/src/cipher/des/des.h b/src/cipher/des/des.h
index 3e53a6166..eb4689849 100644
--- a/src/cipher/des/des.h
+++ b/src/cipher/des/des.h
@@ -21,30 +21,9 @@ class BOTAN_DLL DES : public BlockCipher
       BlockCipher* clone() const { return new DES; }
       DES() : BlockCipher(8, 8) {}
    private:
-      friend class TripleDES;
-
       void enc(const byte[], byte[]) const;
       void dec(const byte[], byte[]) const;
       void key(const byte[], u32bit);
-      void raw_encrypt(u32bit&, u32bit&) const;
-      void raw_decrypt(u32bit&, u32bit&) const;
-      void round(u32bit&, u32bit, u32bit) const;
-      static void IP(u32bit&, u32bit&);
-      static void FP(u32bit&, u32bit&);
-
-      static const u32bit SPBOX1[256];
-      static const u32bit SPBOX2[256];
-      static const u32bit SPBOX3[256];
-      static const u32bit SPBOX4[256];
-      static const u32bit SPBOX5[256];
-      static const u32bit SPBOX6[256];
-      static const u32bit SPBOX7[256];
-      static const u32bit SPBOX8[256];
-
-      static const u64bit IPTAB1[256];
-      static const u64bit IPTAB2[256];
-      static const u64bit FPTAB1[256];
-      static const u64bit FPTAB2[256];
 
       SecureBuffer<u32bit, 32> round_key;
    };
@@ -55,7 +34,7 @@ class BOTAN_DLL DES : public BlockCipher
 class BOTAN_DLL TripleDES : public BlockCipher
    {
    public:
-      void clear() throw() { des1.clear(); des2.clear(); des3.clear(); }
+      void clear() throw() { round_key.clear(); }
       std::string name() const { return "TripleDES"; }
       BlockCipher* clone() const { return new TripleDES; }
       TripleDES() : BlockCipher(8, 16, 24, 8) {}
@@ -63,26 +42,26 @@ class BOTAN_DLL TripleDES : public BlockCipher
       void enc(const byte[], byte[]) const;
       void dec(const byte[], byte[]) const;
       void key(const byte[], u32bit);
-      DES des1, des2, des3;
+
+      SecureBuffer<u32bit, 96> round_key;
    };
 
 /*************************************************
-* DESX                                           *
+* DES Tables                                     *
 *************************************************/
-class BOTAN_DLL DESX : public BlockCipher
-   {
-   public:
-      void clear() throw() { des.clear(); K1.clear(); K2.clear(); }
-      std::string name() const { return "DESX"; }
-      BlockCipher* clone() const { return new DESX; }
-      DESX() : BlockCipher(8, 24) {}
-   private:
-      void enc(const byte[], byte[]) const;
-      void dec(const byte[], byte[]) const;
-      void key(const byte[], u32bit);
-      SecureBuffer<byte, 8> K1, K2;
-      DES des;
-   };
+extern const u32bit DES_SPBOX1[256];
+extern const u32bit DES_SPBOX2[256];
+extern const u32bit DES_SPBOX3[256];
+extern const u32bit DES_SPBOX4[256];
+extern const u32bit DES_SPBOX5[256];
+extern const u32bit DES_SPBOX6[256];
+extern const u32bit DES_SPBOX7[256];
+extern const u32bit DES_SPBOX8[256];
+
+extern const u64bit DES_IPTAB1[256];
+extern const u64bit DES_IPTAB2[256];
+extern const u64bit DES_FPTAB1[256];
+extern const u64bit DES_FPTAB2[256];
 
 }
 
diff --git a/src/cipher/des/des_tab.cpp b/src/cipher/des/des_tab.cpp
index 9788cd8c0..aa3b7cd45 100644
--- a/src/cipher/des/des_tab.cpp
+++ b/src/cipher/des/des_tab.cpp
@@ -7,7 +7,7 @@
 
 namespace Botan {
 
-const u32bit DES::SPBOX1[256] = {
+const u32bit DES_SPBOX1[256] = {
    0x01010400, 0x00000000, 0x00010000, 0x01010404, 0x01010004, 0x00010404,
    0x00000004, 0x00010000, 0x00000400, 0x01010400, 0x01010404, 0x00000400,
    0x01000404, 0x01010004, 0x01000000, 0x00000004, 0x00000404, 0x01000400,
@@ -52,7 +52,7 @@ const u32bit DES::SPBOX1[256] = {
    0x00010404, 0x01010400, 0x00000404, 0x01000400, 0x01000400, 0x00000000,
    0x00010004, 0x00010400, 0x00000000, 0x01010004 };
 
-const u32bit DES::SPBOX2[256] = {
+const u32bit DES_SPBOX2[256] = {
    0x80108020, 0x80008000, 0x00008000, 0x00108020, 0x00100000, 0x00000020,
    0x80100020, 0x80008020, 0x80000020, 0x80108020, 0x80108000, 0x80000000,
    0x80008000, 0x00100000, 0x00000020, 0x80100020, 0x00108000, 0x00100020,
@@ -97,7 +97,7 @@ const u32bit DES::SPBOX2[256] = {
    0x80000020, 0x00100020, 0x00108000, 0x00000000, 0x80008000, 0x00008020,
    0x80000000, 0x80100020, 0x80108020, 0x00108000 };
 
-const u32bit DES::SPBOX3[256] = {
+const u32bit DES_SPBOX3[256] = {
    0x00000208, 0x08020200, 0x00000000, 0x08020008, 0x08000200, 0x00000000,
    0x00020208, 0x08000200, 0x00020008, 0x08000008, 0x08000008, 0x00020000,
    0x08020208, 0x00020008, 0x08020000, 0x00000208, 0x08000000, 0x00000008,
@@ -142,7 +142,7 @@ const u32bit DES::SPBOX3[256] = {
    0x00020200, 0x08000008, 0x08020000, 0x08000208, 0x00000208, 0x08020000,
    0x00020208, 0x00000008, 0x08020008, 0x00020200 };
 
-const u32bit DES::SPBOX4[256] = {
+const u32bit DES_SPBOX4[256] = {
    0x00802001, 0x00002081, 0x00002081, 0x00000080, 0x00802080, 0x00800081,
    0x00800001, 0x00002001, 0x00000000, 0x00802000, 0x00802000, 0x00802081,
    0x00000081, 0x00000000, 0x00800080, 0x00800001, 0x00000001, 0x00002000,
@@ -187,7 +187,7 @@ const u32bit DES::SPBOX4[256] = {
    0x00802080, 0x00800081, 0x00002001, 0x00002080, 0x00800000, 0x00802001,
    0x00000080, 0x00800000, 0x00002000, 0x00802080 };
 
-const u32bit DES::SPBOX5[256] = {
+const u32bit DES_SPBOX5[256] = {
    0x00000100, 0x02080100, 0x02080000, 0x42000100, 0x00080000, 0x00000100,
    0x40000000, 0x02080000, 0x40080100, 0x00080000, 0x02000100, 0x40080100,
    0x42000100, 0x42080000, 0x00080100, 0x40000000, 0x02000000, 0x40080000,
@@ -232,7 +232,7 @@ const u32bit DES::SPBOX5[256] = {
    0x40080000, 0x42000000, 0x00080100, 0x02000100, 0x40000100, 0x00080000,
    0x00000000, 0x40080000, 0x02080100, 0x40000100 };
 
-const u32bit DES::SPBOX6[256] = {
+const u32bit DES_SPBOX6[256] = {
    0x20000010, 0x20400000, 0x00004000, 0x20404010, 0x20400000, 0x00000010,
    0x20404010, 0x00400000, 0x20004000, 0x00404010, 0x00400000, 0x20000010,
    0x00400010, 0x20004000, 0x20000000, 0x00004010, 0x00000000, 0x00400010,
@@ -277,7 +277,7 @@ const u32bit DES::SPBOX6[256] = {
    0x20400000, 0x00404010, 0x00004000, 0x00400010, 0x20004010, 0x00000000,
    0x20404000, 0x20000000, 0x00400010, 0x20004010 };
 
-const u32bit DES::SPBOX7[256] = {
+const u32bit DES_SPBOX7[256] = {
    0x00200000, 0x04200002, 0x04000802, 0x00000000, 0x00000800, 0x04000802,
    0x00200802, 0x04200800, 0x04200802, 0x00200000, 0x00000000, 0x04000002,
    0x00000002, 0x04000000, 0x04200002, 0x00000802, 0x04000800, 0x00200802,
@@ -322,7 +322,7 @@ const u32bit DES::SPBOX7[256] = {
    0x00000002, 0x04200802, 0x00000000, 0x00200802, 0x04200000, 0x00000800,
    0x04000002, 0x04000800, 0x00000800, 0x00200002 };
 
-const u32bit DES::SPBOX8[256] = {
+const u32bit DES_SPBOX8[256] = {
    0x10001040, 0x00001000, 0x00040000, 0x10041040, 0x10000000, 0x10001040,
    0x00000040, 0x10000000, 0x00040040, 0x10040000, 0x10041040, 0x00041000,
    0x10041000, 0x00041040, 0x00001000, 0x00000040, 0x10040000, 0x10000040,
@@ -367,7 +367,7 @@ const u32bit DES::SPBOX8[256] = {
    0x10001040, 0x00000000, 0x10041040, 0x00041000, 0x00041000, 0x00001040,
    0x00001040, 0x00040040, 0x10000000, 0x10041000 };
 
-const u64bit DES::IPTAB1[256] = {
+const u64bit DES_IPTAB1[256] = {
 0x0000000000000000, 0x0000000200000000, 0x0000000000000002, 0x0000000200000002,
 0x0000020000000000, 0x0000020200000000, 0x0000020000000002, 0x0000020200000002,
 0x0000000000000200, 0x0000000200000200, 0x0000000000000202, 0x0000000200000202,
@@ -433,7 +433,7 @@ const u64bit DES::IPTAB1[256] = {
 0x0202000002020200, 0x0202000202020200, 0x0202000002020202, 0x0202000202020202,
 0x0202020002020200, 0x0202020202020200, 0x0202020002020202, 0x0202020202020202 };
 
-const u64bit DES::IPTAB2[256] = {
+const u64bit DES_IPTAB2[256] = {
 0x0000000000000000, 0x0000010000000000, 0x0000000000000100, 0x0000010000000100,
 0x0001000000000000, 0x0001010000000000, 0x0001000000000100, 0x0001010000000100,
 0x0000000000010000, 0x0000010000010000, 0x0000000000010100, 0x0000010000010100,
@@ -499,7 +499,7 @@ const u64bit DES::IPTAB2[256] = {
 0x0100000101010001, 0x0100010101010001, 0x0100000101010101, 0x0100010101010101,
 0x0101000101010001, 0x0101010101010001, 0x0101000101010101, 0x0101010101010101 };
 
-const u64bit DES::FPTAB1[256] = {
+const u64bit DES_FPTAB1[256] = {
 0x0000000000000000, 0x0000000100000000, 0x0000000004000000, 0x0000000104000000,
 0x0000000000040000, 0x0000000100040000, 0x0000000004040000, 0x0000000104040000,
 0x0000000000000400, 0x0000000100000400, 0x0000000004000400, 0x0000000104000400,
@@ -565,7 +565,7 @@ const u64bit DES::FPTAB1[256] = {
 0x0404040000000404, 0x0404040100000404, 0x0404040004000404, 0x0404040104000404,
 0x0404040000040404, 0x0404040100040404, 0x0404040004040404, 0x0404040104040404 };
 
-const u64bit DES::FPTAB2[256] = {
+const u64bit DES_FPTAB2[256] = {
 0x0000000000000000, 0x0000004000000000, 0x0000000001000000, 0x0000004001000000,
 0x0000000000010000, 0x0000004000010000, 0x0000000001010000, 0x0000004001010000,
 0x0000000000000100, 0x0000004000000100, 0x0000000001000100, 0x0000004001000100,
diff --git a/src/cipher/des/desx.cpp b/src/cipher/des/desx.cpp
new file mode 100644
index 000000000..fb76ec731
--- /dev/null
+++ b/src/cipher/des/desx.cpp
@@ -0,0 +1,41 @@
+/*************************************************
+* DES Source File                                *
+* (C) 1999-2007 Jack Lloyd                       *
+*************************************************/
+
+#include <botan/desx.h>
+#include <botan/xor_buf.h>
+
+namespace Botan {
+
+/*************************************************
+* DESX Encryption                                *
+*************************************************/
+void DESX::enc(const byte in[], byte out[]) const
+   {
+   xor_buf(out, in, K1.begin(), BLOCK_SIZE);
+   des.encrypt(out);
+   xor_buf(out, K2.begin(), BLOCK_SIZE);
+   }
+
+/*************************************************
+* DESX Decryption                                *
+*************************************************/
+void DESX::dec(const byte in[], byte out[]) const
+   {
+   xor_buf(out, in, K2.begin(), BLOCK_SIZE);
+   des.decrypt(out);
+   xor_buf(out, K1.begin(), BLOCK_SIZE);
+   }
+
+/*************************************************
+* DESX Key Schedule                              *
+*************************************************/
+void DESX::key(const byte key[], u32bit)
+   {
+   K1.copy(key, 8);
+   des.set_key(key + 8, 8);
+   K2.copy(key + 16, 8);
+   }
+
+}
diff --git a/src/cipher/des/desx.h b/src/cipher/des/desx.h
new file mode 100644
index 000000000..c7e407b62
--- /dev/null
+++ b/src/cipher/des/desx.h
@@ -0,0 +1,33 @@
+/*************************************************
+* DESX Header File                               *
+* (C) 1999-2007 Jack Lloyd                       *
+*************************************************/
+
+#ifndef BOTAN_DESX_H__
+#define BOTAN_DESX_H__
+
+#include <botan/des.h>
+
+namespace Botan {
+
+/*************************************************
+* DESX                                           *
+*************************************************/
+class BOTAN_DLL DESX : public BlockCipher
+   {
+   public:
+      void clear() throw() { des.clear(); K1.clear(); K2.clear(); }
+      std::string name() const { return "DESX"; }
+      BlockCipher* clone() const { return new DESX; }
+      DESX() : BlockCipher(8, 24) {}
+   private:
+      void enc(const byte[], byte[]) const;
+      void dec(const byte[], byte[]) const;
+      void key(const byte[], u32bit);
+      SecureBuffer<byte, 8> K1, K2;
+      DES des;
+   };
+
+}
+
+#endif
diff --git a/src/cipher/des/info.txt b/src/cipher/des/info.txt
index 43ea9a0bc..ed05979c9 100644
--- a/src/cipher/des/info.txt
+++ b/src/cipher/des/info.txt
@@ -8,4 +8,6 @@ load_on auto
 des.cpp
 des.h
 des_tab.cpp
+desx.h
+desx.cpp
 </add>
diff --git a/src/core/libstate/def_alg.cpp b/src/core/libstate/def_alg.cpp
index b7c812a59..6f89fa121 100644
--- a/src/core/libstate/def_alg.cpp
+++ b/src/core/libstate/def_alg.cpp
@@ -24,6 +24,7 @@
 
 #if defined(BOTAN_HAS_DES)
   #include <botan/des.h>
+  #include <botan/desx.h>
 #endif
 
 #if defined(BOTAN_HAS_GOST)