Commit e2b21b50 authored by Denys Vlasenko's avatar Denys Vlasenko Committed by Herbert Xu
Browse files

[CRYPTO] twofish: Do not unroll big stuff in twofish key setup 



Currently twofish cipher key setup code
has unrolled loops - approximately 70-100
instructions are repeated 40 times.

As a result, twofish module is the biggest module
in crypto/*.

Unrolling produces x2.5 more code (+18k on i386), and speeds up key
setup by 7%:

	unrolled: twofish_setkey/sec: 41128
	    loop: twofish_setkey/sec: 38148
	CALC_K256: ~100 insns each
	CALC_K192: ~90 insns
	   CALC_K: ~70 insns

Attached patch removes this unrolling.

$ size */twofish_common.o
   text    data     bss     dec     hex filename
  37920       0       0   37920    9420 crypto.org/twofish_common.o
  13209       0       0   13209    3399 crypto/twofish_common.o

Run tested (modprobe tcrypt reports ok). Please apply.

Signed-off-by: default avatarDenys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent b7a30da6

crypto/twofish_common.c

+30 −66
Original line number Diff line number Diff line
@@ -655,84 +655,48 @@ int twofish_setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int key_len) 
			CALC_SB256_2( i, calc_sb_tbl[j], calc_sb_tbl[k] );

		}



		/* Calculate whitening and round subkeys.  The constants are

		 * indices of subkeys, preprocessed through q0 and q1. */

		CALC_K256 (w, 0, 0xA9, 0x75, 0x67, 0xF3);

		CALC_K256 (w, 2, 0xB3, 0xC6, 0xE8, 0xF4);

		CALC_K256 (w, 4, 0x04, 0xDB, 0xFD, 0x7B);

		CALC_K256 (w, 6, 0xA3, 0xFB, 0x76, 0xC8);

		CALC_K256 (k, 0, 0x9A, 0x4A, 0x92, 0xD3);

		CALC_K256 (k, 2, 0x80, 0xE6, 0x78, 0x6B);

		CALC_K256 (k, 4, 0xE4, 0x45, 0xDD, 0x7D);

		CALC_K256 (k, 6, 0xD1, 0xE8, 0x38, 0x4B);

		CALC_K256 (k, 8, 0x0D, 0xD6, 0xC6, 0x32);

		CALC_K256 (k, 10, 0x35, 0xD8, 0x98, 0xFD);

		CALC_K256 (k, 12, 0x18, 0x37, 0xF7, 0x71);

		CALC_K256 (k, 14, 0xEC, 0xF1, 0x6C, 0xE1);

		CALC_K256 (k, 16, 0x43, 0x30, 0x75, 0x0F);

		CALC_K256 (k, 18, 0x37, 0xF8, 0x26, 0x1B);

		CALC_K256 (k, 20, 0xFA, 0x87, 0x13, 0xFA);

		CALC_K256 (k, 22, 0x94, 0x06, 0x48, 0x3F);

		CALC_K256 (k, 24, 0xF2, 0x5E, 0xD0, 0xBA);

		CALC_K256 (k, 26, 0x8B, 0xAE, 0x30, 0x5B);

		CALC_K256 (k, 28, 0x84, 0x8A, 0x54, 0x00);

		CALC_K256 (k, 30, 0xDF, 0xBC, 0x23, 0x9D);

		/* CALC_K256/CALC_K192/CALC_K loops were unrolled.

		 * Unrolling produced x2.5 more code (+18k on i386),

		 * and speeded up key setup by 7%:

		 * unrolled: twofish_setkey/sec: 41128

		 *     loop: twofish_setkey/sec: 38148

		 * CALC_K256: ~100 insns each

		 * CALC_K192: ~90 insns

		 *    CALC_K: ~70 insns

		 */

		/* Calculate whitening and round subkeys */

		for ( i = 0; i < 8; i += 2 ) {

			CALC_K256 (w, i, q0[i], q1[i], q0[i+1], q1[i+1]);

		}

		for ( i = 0; i < 32; i += 2 ) {

			CALC_K256 (k, i, q0[i+8], q1[i+8], q0[i+9], q1[i+9]);

		}

	} else if (key_len == 24) { /* 192-bit key */

		/* Compute the S-boxes. */

		for ( i = j = 0, k = 1; i < 256; i++, j += 2, k += 2 ) {

		        CALC_SB192_2( i, calc_sb_tbl[j], calc_sb_tbl[k] );

		}



		/* Calculate whitening and round subkeys.  The constants are

		 * indices of subkeys, preprocessed through q0 and q1. */

		CALC_K192 (w, 0, 0xA9, 0x75, 0x67, 0xF3);

		CALC_K192 (w, 2, 0xB3, 0xC6, 0xE8, 0xF4);

		CALC_K192 (w, 4, 0x04, 0xDB, 0xFD, 0x7B);

		CALC_K192 (w, 6, 0xA3, 0xFB, 0x76, 0xC8);

		CALC_K192 (k, 0, 0x9A, 0x4A, 0x92, 0xD3);

		CALC_K192 (k, 2, 0x80, 0xE6, 0x78, 0x6B);

		CALC_K192 (k, 4, 0xE4, 0x45, 0xDD, 0x7D);

		CALC_K192 (k, 6, 0xD1, 0xE8, 0x38, 0x4B);

		CALC_K192 (k, 8, 0x0D, 0xD6, 0xC6, 0x32);

		CALC_K192 (k, 10, 0x35, 0xD8, 0x98, 0xFD);

		CALC_K192 (k, 12, 0x18, 0x37, 0xF7, 0x71);

		CALC_K192 (k, 14, 0xEC, 0xF1, 0x6C, 0xE1);

		CALC_K192 (k, 16, 0x43, 0x30, 0x75, 0x0F);

		CALC_K192 (k, 18, 0x37, 0xF8, 0x26, 0x1B);

		CALC_K192 (k, 20, 0xFA, 0x87, 0x13, 0xFA);

		CALC_K192 (k, 22, 0x94, 0x06, 0x48, 0x3F);

		CALC_K192 (k, 24, 0xF2, 0x5E, 0xD0, 0xBA);

		CALC_K192 (k, 26, 0x8B, 0xAE, 0x30, 0x5B);

		CALC_K192 (k, 28, 0x84, 0x8A, 0x54, 0x00);

		CALC_K192 (k, 30, 0xDF, 0xBC, 0x23, 0x9D);

		/* Calculate whitening and round subkeys */

		for ( i = 0; i < 8; i += 2 ) {

			CALC_K192 (w, i, q0[i], q1[i], q0[i+1], q1[i+1]);

		}

		for ( i = 0; i < 32; i += 2 ) {

			CALC_K192 (k, i, q0[i+8], q1[i+8], q0[i+9], q1[i+9]);

		}

	} else { /* 128-bit key */

		/* Compute the S-boxes. */

		for ( i = j = 0, k = 1; i < 256; i++, j += 2, k += 2 ) {

			CALC_SB_2( i, calc_sb_tbl[j], calc_sb_tbl[k] );

		}



		/* Calculate whitening and round subkeys.  The constants are

		 * indices of subkeys, preprocessed through q0 and q1. */

		CALC_K (w, 0, 0xA9, 0x75, 0x67, 0xF3);

		CALC_K (w, 2, 0xB3, 0xC6, 0xE8, 0xF4);

		CALC_K (w, 4, 0x04, 0xDB, 0xFD, 0x7B);

		CALC_K (w, 6, 0xA3, 0xFB, 0x76, 0xC8);

		CALC_K (k, 0, 0x9A, 0x4A, 0x92, 0xD3);

		CALC_K (k, 2, 0x80, 0xE6, 0x78, 0x6B);

		CALC_K (k, 4, 0xE4, 0x45, 0xDD, 0x7D);

		CALC_K (k, 6, 0xD1, 0xE8, 0x38, 0x4B);

		CALC_K (k, 8, 0x0D, 0xD6, 0xC6, 0x32);

		CALC_K (k, 10, 0x35, 0xD8, 0x98, 0xFD);

		CALC_K (k, 12, 0x18, 0x37, 0xF7, 0x71);

		CALC_K (k, 14, 0xEC, 0xF1, 0x6C, 0xE1);

		CALC_K (k, 16, 0x43, 0x30, 0x75, 0x0F);

		CALC_K (k, 18, 0x37, 0xF8, 0x26, 0x1B);

		CALC_K (k, 20, 0xFA, 0x87, 0x13, 0xFA);

		CALC_K (k, 22, 0x94, 0x06, 0x48, 0x3F);

		CALC_K (k, 24, 0xF2, 0x5E, 0xD0, 0xBA);

		CALC_K (k, 26, 0x8B, 0xAE, 0x30, 0x5B);

		CALC_K (k, 28, 0x84, 0x8A, 0x54, 0x00);

		CALC_K (k, 30, 0xDF, 0xBC, 0x23, 0x9D);

		/* Calculate whitening and round subkeys */

		for ( i = 0; i < 8; i += 2 ) {

			CALC_K (w, i, q0[i], q1[i], q0[i+1], q1[i+1]);

		}

		for ( i = 0; i < 32; i += 2 ) {

			CALC_K (k, i, q0[i+8], q1[i+8], q0[i+9], q1[i+9]);

		}

	}



	return 0;

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