X-Git-Url: https://git.cryptolib.org/?a=blobdiff_plain;f=serpent.c;h=4960664669ec1fe8a4647604b3ac2233434a71fc;hb=0f66a12e93ed43904c30810ac33c79c87befafe7;hp=8056eb41d03e1b9623d026e30d2b48db8548e1a7;hpb=2159c273c9d3361571a6ff1ab63d9bc76582fbab;p=avr-crypto-lib.git diff --git a/serpent.c b/serpent.c index 8056eb4..4960664 100644 --- a/serpent.c +++ b/serpent.c @@ -47,7 +47,9 @@ uint32_t rotr32(uint32_t a, uint8_t n){ #define X2 (((uint32_t*)b)[2]) #define X3 (((uint32_t*)b)[3]) -static void lt(uint8_t *b){ +void serpent_lt(uint8_t *b); +/* +static void serpent_lt(uint8_t *b){ X0 = rotl32(X0, 13); X2 = rotl32(X2, 3); X1 ^= X0 ^ X2; @@ -59,8 +61,12 @@ static void lt(uint8_t *b){ X0 = rotl32(X0, 5); X2 = rotr32(X2, 10); } +*/ + +static void serpent_inv_lt(uint8_t *b); -static void inv_lt(uint8_t *b){ +/* +static void serpent_inv_lt(uint8_t *b){ X2 = rotl32(X2, 10); X0 = rotr32(X0, 5); X2 ^= X3 ^ (X1 << 7); @@ -72,17 +78,19 @@ static void inv_lt(uint8_t *b){ X2 = rotr32(X2, 3); X0 = rotr32(X0, 13); } +*/ +uint32_t serpent_gen_w(uint32_t * b, uint8_t i); +/* #define GOLDEN_RATIO 0x9e3779b9l -static uint32_t gen_w(uint32_t * b, uint8_t i){ +static uint32_t serpent_gen_w(uint32_t * b, uint8_t i){ uint32_t ret; ret = b[0] ^ b[3] ^ b[5] ^ b[7] ^ GOLDEN_RATIO ^ (uint32_t)i; ret = rotl32(ret, 11); return ret; } - -/* key must be 256bit (32 byte) large! */ +*/ void serpent_init(const void* key, uint16_t keysize, serpent_ctx_t* ctx){ uint32_t buffer[8]; uint8_t i,j; @@ -97,7 +105,7 @@ void serpent_init(const void* key, uint16_t keysize, serpent_ctx_t* ctx){ } for(i=0; i<33; ++i){ for(j=0; j<4; ++j){ - ctx->k[i][j] = gen_w(buffer, i*4+j); + ctx->k[i][j] = serpent_gen_w(buffer, i*4+j); memmove(buffer, &(buffer[1]), 7*4); /* shift buffer one to the "left" */ buffer[7] = ctx->k[i][j]; } @@ -111,28 +119,28 @@ void serpent_init(const void* key, uint16_t keysize, serpent_ctx_t* ctx){ void serpent_enc(void* buffer, const serpent_ctx_t* ctx){ uint8_t i; for(i=0; i<31; ++i){ - memxor((uint8_t*)buffer, ctx->k[i], 16); + memxor(buffer, ctx->k[i], 16); sbox128(buffer, i); - lt((uint8_t*)buffer); + serpent_lt((uint8_t*)buffer); } - memxor((uint8_t*)buffer, ctx->k[i], 16); + memxor(buffer, ctx->k[i], 16); sbox128(buffer, i); ++i; - memxor((uint8_t*)buffer, ctx->k[i], 16); + memxor(buffer, ctx->k[i], 16); } void serpent_dec(void* buffer, const serpent_ctx_t* ctx){ int8_t i=32; - memxor((uint8_t*)buffer, ctx->k[i], 16); + memxor(buffer, ctx->k[i], 16); --i; inv_sbox128(buffer, i); memxor((uint8_t*)buffer, ctx->k[i], 16); --i; for(; i>=0; --i){ - inv_lt((uint8_t*)buffer); + serpent_inv_lt(buffer); inv_sbox128(buffer, i); - memxor((uint8_t*)buffer, ctx->k[i], 16); + memxor(buffer, ctx->k[i], 16); } }