aboutsummaryrefslogtreecommitdiffstats
path: root/src
diff options
context:
space:
mode:
Diffstat (limited to 'src')
-rw-r--r--src/block/skipjack/skipjack.cpp175
-rw-r--r--src/block/skipjack/skipjack.h6
2 files changed, 99 insertions, 82 deletions
diff --git a/src/block/skipjack/skipjack.cpp b/src/block/skipjack/skipjack.cpp
index e8b2cfb8d..b23d1e160 100644
--- a/src/block/skipjack/skipjack.cpp
+++ b/src/block/skipjack/skipjack.cpp
@@ -10,6 +10,68 @@
namespace Botan {
+namespace {
+
+/*
+* Skipjack Stepping Rule 'A'
+*/
+void step_A(u16bit& W1, u16bit& W4, u32bit round, const byte FTAB[])
+ {
+ byte G1 = get_byte(0, W1), G2 = get_byte(1, W1), G3;
+
+ G3 = FTAB[((4*round-4)%10)*256 + G2] ^ G1;
+ G1 = FTAB[((4*round-3)%10)*256 + G3] ^ G2;
+ G2 = FTAB[((4*round-2)%10)*256 + G1] ^ G3;
+ G3 = FTAB[((4*round-1)%10)*256 + G2] ^ G1;
+
+ W1 = make_u16bit(G2, G3);
+ W4 ^= W1 ^ round;
+ }
+
+/*
+* Skipjack Stepping Rule 'B'
+*/
+void step_B(u16bit& W1, u16bit& W2, u32bit round, const byte FTAB[])
+ {
+ W2 ^= W1 ^ round;
+ byte G1 = get_byte(0, W1), G2 = get_byte(1, W1), G3;
+ G3 = FTAB[((4*round-4)%10)*256 + G2] ^ G1;
+ G1 = FTAB[((4*round-3)%10)*256 + G3] ^ G2;
+ G2 = FTAB[((4*round-2)%10)*256 + G1] ^ G3;
+ G3 = FTAB[((4*round-1)%10)*256 + G2] ^ G1;
+ W1 = make_u16bit(G2, G3);
+ }
+
+/*
+* Skipjack Invserse Stepping Rule 'A'
+*/
+void step_Ai(u16bit& W1, u16bit& W2, u32bit round, const byte FTAB[])
+ {
+ W1 ^= W2 ^ round;
+ byte G1 = get_byte(1, W2), G2 = get_byte(0, W2), G3;
+ G3 = FTAB[((4 * round - 1) % 10)*256 + G2] ^ G1;
+ G1 = FTAB[((4 * round - 2) % 10)*256 + G3] ^ G2;
+ G2 = FTAB[((4 * round - 3) % 10)*256 + G1] ^ G3;
+ G3 = FTAB[((4 * round - 4) % 10)*256 + G2] ^ G1;
+ W2 = make_u16bit(G3, G2);
+ }
+
+/*
+* Skipjack Invserse Stepping Rule 'B'
+*/
+void step_Bi(u16bit& W2, u16bit& W3, u32bit round, const byte FTAB[])
+ {
+ byte G1 = get_byte(1, W2), G2 = get_byte(0, W2), G3;
+ G3 = FTAB[((4 * round - 1) % 10)*256 + G2] ^ G1;
+ G1 = FTAB[((4 * round - 2) % 10)*256 + G3] ^ G2;
+ G2 = FTAB[((4 * round - 3) % 10)*256 + G1] ^ G3;
+ G3 = FTAB[((4 * round - 4) % 10)*256 + G2] ^ G1;
+ W2 = make_u16bit(G3, G2);
+ W3 ^= W2 ^ round;
+ }
+
+}
+
/*
* Skipjack Encryption
*/
@@ -22,17 +84,25 @@ void Skipjack::encrypt_n(const byte in[], byte out[], u32bit blocks) const
u16bit W3 = load_le<u16bit>(in, 1);
u16bit W4 = load_le<u16bit>(in, 0);
- step_A(W1,W4, 1); step_A(W4,W3, 2); step_A(W3,W2, 3); step_A(W2,W1, 4);
- step_A(W1,W4, 5); step_A(W4,W3, 6); step_A(W3,W2, 7); step_A(W2,W1, 8);
+ step_A(W1, W4, 1, FTAB); step_A(W4, W3, 2, FTAB);
+ step_A(W3, W2, 3, FTAB); step_A(W2, W1, 4, FTAB);
+ step_A(W1, W4, 5, FTAB); step_A(W4, W3, 6, FTAB);
+ step_A(W3, W2, 7, FTAB); step_A(W2, W1, 8, FTAB);
- step_B(W1,W2, 9); step_B(W4,W1,10); step_B(W3,W4,11); step_B(W2,W3,12);
- step_B(W1,W2,13); step_B(W4,W1,14); step_B(W3,W4,15); step_B(W2,W3,16);
+ step_B(W1, W2, 9, FTAB); step_B(W4, W1, 10, FTAB);
+ step_B(W3, W4, 11, FTAB); step_B(W2, W3, 12, FTAB);
+ step_B(W1, W2, 13, FTAB); step_B(W4, W1, 14, FTAB);
+ step_B(W3, W4, 15, FTAB); step_B(W2, W3, 16, FTAB);
- step_A(W1,W4,17); step_A(W4,W3,18); step_A(W3,W2,19); step_A(W2,W1,20);
- step_A(W1,W4,21); step_A(W4,W3,22); step_A(W3,W2,23); step_A(W2,W1,24);
+ step_A(W1, W4, 17, FTAB); step_A(W4, W3, 18, FTAB);
+ step_A(W3, W2, 19, FTAB); step_A(W2, W1, 20, FTAB);
+ step_A(W1, W4, 21, FTAB); step_A(W4, W3, 22, FTAB);
+ step_A(W3, W2, 23, FTAB); step_A(W2, W1, 24, FTAB);
- step_B(W1,W2,25); step_B(W4,W1,26); step_B(W3,W4,27); step_B(W2,W3,28);
- step_B(W1,W2,29); step_B(W4,W1,30); step_B(W3,W4,31); step_B(W2,W3,32);
+ step_B(W1, W2, 25, FTAB); step_B(W4, W1, 26, FTAB);
+ step_B(W3, W4, 27, FTAB); step_B(W2, W3, 28, FTAB);
+ step_B(W1, W2, 29, FTAB); step_B(W4, W1, 30, FTAB);
+ step_B(W3, W4, 31, FTAB); step_B(W2, W3, 32, FTAB);
store_le(out, W4, W3, W2, W1);
@@ -53,17 +123,25 @@ void Skipjack::decrypt_n(const byte in[], byte out[], u32bit blocks) const
u16bit W3 = load_le<u16bit>(in, 1);
u16bit W4 = load_le<u16bit>(in, 0);
- step_Bi(W2,W3,32); step_Bi(W3,W4,31); step_Bi(W4,W1,30); step_Bi(W1,W2,29);
- step_Bi(W2,W3,28); step_Bi(W3,W4,27); step_Bi(W4,W1,26); step_Bi(W1,W2,25);
+ step_Bi(W2, W3, 32, FTAB); step_Bi(W3, W4, 31, FTAB);
+ step_Bi(W4, W1, 30, FTAB); step_Bi(W1, W2, 29, FTAB);
+ step_Bi(W2, W3, 28, FTAB); step_Bi(W3, W4, 27, FTAB);
+ step_Bi(W4, W1, 26, FTAB); step_Bi(W1, W2, 25, FTAB);
- step_Ai(W1,W2,24); step_Ai(W2,W3,23); step_Ai(W3,W4,22); step_Ai(W4,W1,21);
- step_Ai(W1,W2,20); step_Ai(W2,W3,19); step_Ai(W3,W4,18); step_Ai(W4,W1,17);
+ step_Ai(W1, W2, 24, FTAB); step_Ai(W2, W3, 23, FTAB);
+ step_Ai(W3, W4, 22, FTAB); step_Ai(W4, W1, 21, FTAB);
+ step_Ai(W1, W2, 20, FTAB); step_Ai(W2, W3, 19, FTAB);
+ step_Ai(W3, W4, 18, FTAB); step_Ai(W4, W1, 17, FTAB);
- step_Bi(W2,W3,16); step_Bi(W3,W4,15); step_Bi(W4,W1,14); step_Bi(W1,W2,13);
- step_Bi(W2,W3,12); step_Bi(W3,W4,11); step_Bi(W4,W1,10); step_Bi(W1,W2, 9);
+ step_Bi(W2, W3, 16, FTAB); step_Bi(W3, W4, 15, FTAB);
+ step_Bi(W4, W1, 14, FTAB); step_Bi(W1, W2, 13, FTAB);
+ step_Bi(W2, W3, 12, FTAB); step_Bi(W3, W4, 11, FTAB);
+ step_Bi(W4, W1, 10, FTAB); step_Bi(W1, W2, 9, FTAB);
- step_Ai(W1,W2, 8); step_Ai(W2,W3, 7); step_Ai(W3,W4, 6); step_Ai(W4,W1, 5);
- step_Ai(W1,W2, 4); step_Ai(W2,W3, 3); step_Ai(W3,W4, 2); step_Ai(W4,W1, 1);
+ step_Ai(W1, W2, 8, FTAB); step_Ai(W2, W3, 7, FTAB);
+ step_Ai(W3, W4, 6, FTAB); step_Ai(W4, W1, 5, FTAB);
+ step_Ai(W1, W2, 4, FTAB); step_Ai(W2, W3, 3, FTAB);
+ step_Ai(W3, W4, 2, FTAB); step_Ai(W4, W1, 1, FTAB);
store_le(out, W4, W3, W2, W1);
@@ -73,62 +151,6 @@ void Skipjack::decrypt_n(const byte in[], byte out[], u32bit blocks) const
}
/*
-* Skipjack Stepping Rule 'A'
-*/
-void Skipjack::step_A(u16bit& W1, u16bit& W4, u32bit round) const
- {
- byte G1 = get_byte(0, W1), G2 = get_byte(1, W1), G3;
- G3 = FTABLE[(4 * round - 4) % 10][G2] ^ G1;
- G1 = FTABLE[(4 * round - 3) % 10][G3] ^ G2;
- G2 = FTABLE[(4 * round - 2) % 10][G1] ^ G3;
- G3 = FTABLE[(4 * round - 1) % 10][G2] ^ G1;
- W1 = make_u16bit(G2, G3);
- W4 ^= W1 ^ round;
- }
-
-/*
-* Skipjack Stepping Rule 'B'
-*/
-void Skipjack::step_B(u16bit& W1, u16bit& W2, u32bit round) const
- {
- W2 ^= W1 ^ round;
- byte G1 = get_byte(0, W1), G2 = get_byte(1, W1), G3;
- G3 = FTABLE[(4 * round - 4) % 10][G2] ^ G1;
- G1 = FTABLE[(4 * round - 3) % 10][G3] ^ G2;
- G2 = FTABLE[(4 * round - 2) % 10][G1] ^ G3;
- G3 = FTABLE[(4 * round - 1) % 10][G2] ^ G1;
- W1 = make_u16bit(G2, G3);
- }
-
-/*
-* Skipjack Invserse Stepping Rule 'A'
-*/
-void Skipjack::step_Ai(u16bit& W1, u16bit& W2, u32bit round) const
- {
- W1 ^= W2 ^ round;
- byte G1 = get_byte(1, W2), G2 = get_byte(0, W2), G3;
- G3 = FTABLE[(4 * round - 1) % 10][G2] ^ G1;
- G1 = FTABLE[(4 * round - 2) % 10][G3] ^ G2;
- G2 = FTABLE[(4 * round - 3) % 10][G1] ^ G3;
- G3 = FTABLE[(4 * round - 4) % 10][G2] ^ G1;
- W2 = make_u16bit(G3, G2);
- }
-
-/*
-* Skipjack Invserse Stepping Rule 'B'
-*/
-void Skipjack::step_Bi(u16bit& W2, u16bit& W3, u32bit round) const
- {
- byte G1 = get_byte(1, W2), G2 = get_byte(0, W2), G3;
- G3 = FTABLE[(4 * round - 1) % 10][G2] ^ G1;
- G1 = FTABLE[(4 * round - 2) % 10][G3] ^ G2;
- G2 = FTABLE[(4 * round - 3) % 10][G1] ^ G3;
- G3 = FTABLE[(4 * round - 4) % 10][G2] ^ G1;
- W2 = make_u16bit(G3, G2);
- W3 ^= W2 ^ round;
- }
-
-/*
* Skipjack Key Schedule
*/
void Skipjack::key_schedule(const byte key[], u32bit)
@@ -157,9 +179,9 @@ void Skipjack::key_schedule(const byte key[], u32bit)
0x5E, 0x6C, 0xA9, 0x13, 0x57, 0x25, 0xB5, 0xE3, 0xBD, 0xA8, 0x3A, 0x01,
0x05, 0x59, 0x2A, 0x46 };
- for(u32bit j = 0; j != 10; ++j)
- for(u32bit k = 0; k != 256; ++k)
- FTABLE[j][k] = F[k ^ key[9-j]];
+ for(u32bit i = 0; i != 10; ++i)
+ for(u32bit j = 0; j != 256; ++j)
+ FTAB[256*i+j] = F[j ^ key[9-i]];
}
/*
@@ -167,8 +189,7 @@ void Skipjack::key_schedule(const byte key[], u32bit)
*/
void Skipjack::clear()
{
- for(u32bit j = 0; j != 10; ++j)
- FTABLE[j].clear();
+ FTAB.clear();
}
}
diff --git a/src/block/skipjack/skipjack.h b/src/block/skipjack/skipjack.h
index 60fad6310..b701e2091 100644
--- a/src/block/skipjack/skipjack.h
+++ b/src/block/skipjack/skipjack.h
@@ -28,12 +28,8 @@ class BOTAN_DLL Skipjack : public BlockCipher
Skipjack() : BlockCipher(8, 10) {}
private:
void key_schedule(const byte[], u32bit);
- void step_A(u16bit&, u16bit&, u32bit) const;
- void step_B(u16bit&, u16bit&, u32bit) const;
- void step_Ai(u16bit&, u16bit&, u32bit) const;
- void step_Bi(u16bit&, u16bit&, u32bit) const;
- SecureBuffer<byte, 256> FTABLE[10];
+ SecureBuffer<byte, 2560> FTAB;
};
}