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* imported new implementations of HC-256 and HC-128.
#include "ecrypt-sync.h"
/* =====================================================================
* The following defines the keystream generation function
*======================================================================*/
/*h1 function*/
#define h1(ctx, x, y) { \
u32 B0,B2,t0; \
B0 = (u8) (x); \
t0 = (ctx->T[512+B0]); \
B2 = (u8) ((x) >> 16); \
y = t0 + (ctx->T[512+256+B2]); \
}
/*h2 function*/
#define h2(ctx, x, y) { \
u32 B0,B2,t0; \
B0 = (u8) (x); \
t0 = (ctx->T[B0]); \
B2 = (u8) ((x) >> 16); \
y = t0 + (ctx->T[256+B2]); \
}
/*one step of HC-128, update P and generate 32 bits keystream*/
#define step_P(ctx,u,v,a,b,c,d,n){ \
u32 tem0,tem1,tem2,tem3; \
h1((ctx),(ctx->X[(d)]),tem3); \
tem0 = ROTR32((ctx->T[(v)]),23); \
tem1 = ROTR32((ctx->X[(c)]),10); \
tem2 = ROTR32((ctx->X[(b)]),8); \
(ctx->T[(u)]) += tem2+(tem0 ^ tem1); \
(ctx->X[(a)]) = (ctx->T[(u)]); \
(n) = tem3 ^ (ctx->T[(u)]) ; \
}
/*one step of HC-128, update Q and generate 32 bits keystream*/
#define step_Q(ctx,u,v,a,b,c,d,n){ \
u32 tem0,tem1,tem2,tem3; \
h2((ctx),(ctx->Y[(d)]),tem3); \
tem0 = ROTR32((ctx->T[(v)]),(32-23)); \
tem1 = ROTR32((ctx->Y[(c)]),(32-10)); \
tem2 = ROTR32((ctx->Y[(b)]),(32-8)); \
(ctx->T[(u)]) += tem2 + (tem0 ^ tem1); \
(ctx->Y[(a)]) = (ctx->T[(u)]); \
(n) = tem3 ^ (ctx->T[(u)]) ; \
}
/*16 steps of HC-128, generate 512 bits keystream*/
void generate_keystream(ECRYPT_ctx* ctx, u32* keystream)
{
u32 cc,dd;
cc = ctx->counter1024 & 0x1ff;
dd = (cc+16)&0x1ff;
if (ctx->counter1024 < 512)
{
ctx->counter1024 = (ctx->counter1024 + 16) & 0x3ff;
step_P(ctx, cc+0, cc+1, 0, 6, 13,4, keystream[0]);
step_P(ctx, cc+1, cc+2, 1, 7, 14,5, keystream[1]);
step_P(ctx, cc+2, cc+3, 2, 8, 15,6, keystream[2]);
step_P(ctx, cc+3, cc+4, 3, 9, 0, 7, keystream[3]);
step_P(ctx, cc+4, cc+5, 4, 10,1, 8, keystream[4]);
step_P(ctx, cc+5, cc+6, 5, 11,2, 9, keystream[5]);
step_P(ctx, cc+6, cc+7, 6, 12,3, 10,keystream[6]);
step_P(ctx, cc+7, cc+8, 7, 13,4, 11,keystream[7]);
step_P(ctx, cc+8, cc+9, 8, 14,5, 12,keystream[8]);
step_P(ctx, cc+9, cc+10,9, 15,6, 13,keystream[9]);
step_P(ctx, cc+10,cc+11,10,0, 7, 14,keystream[10]);
step_P(ctx, cc+11,cc+12,11,1, 8, 15,keystream[11]);
step_P(ctx, cc+12,cc+13,12,2, 9, 0, keystream[12]);
step_P(ctx, cc+13,cc+14,13,3, 10,1, keystream[13]);
step_P(ctx, cc+14,cc+15,14,4, 11,2, keystream[14]);
step_P(ctx, cc+15,dd+0, 15,5, 12,3, keystream[15]);
}
else
{
ctx->counter1024 = (ctx->counter1024 + 16) & 0x3ff;
step_Q(ctx, 512+cc+0, 512+cc+1, 0, 6, 13,4, keystream[0]);
step_Q(ctx, 512+cc+1, 512+cc+2, 1, 7, 14,5, keystream[1]);
step_Q(ctx, 512+cc+2, 512+cc+3, 2, 8, 15,6, keystream[2]);
step_Q(ctx, 512+cc+3, 512+cc+4, 3, 9, 0, 7, keystream[3]);
step_Q(ctx, 512+cc+4, 512+cc+5, 4, 10,1, 8, keystream[4]);
step_Q(ctx, 512+cc+5, 512+cc+6, 5, 11,2, 9, keystream[5]);
step_Q(ctx, 512+cc+6, 512+cc+7, 6, 12,3, 10,keystream[6]);
step_Q(ctx, 512+cc+7, 512+cc+8, 7, 13,4, 11,keystream[7]);
step_Q(ctx, 512+cc+8, 512+cc+9, 8, 14,5, 12,keystream[8]);
step_Q(ctx, 512+cc+9, 512+cc+10,9, 15,6, 13,keystream[9]);
step_Q(ctx, 512+cc+10,512+cc+11,10,0, 7, 14,keystream[10]);
step_Q(ctx, 512+cc+11,512+cc+12,11,1, 8, 15,keystream[11]);
step_Q(ctx, 512+cc+12,512+cc+13,12,2, 9, 0, keystream[12]);
step_Q(ctx, 512+cc+13,512+cc+14,13,3, 10,1, keystream[13]);
step_Q(ctx, 512+cc+14,512+cc+15,14,4, 11,2, keystream[14]);
step_Q(ctx, 512+cc+15,512+dd+0, 15,5, 12,3, keystream[15]);
}
}
/*======================================================*/
/* The following defines the initialization functions */
/*======================================================*/
#define f1(x) (ROTR32((x),7) ^ ROTR32((x),18) ^ ((x) >> 3))
#define f2(x) (ROTR32((x),17) ^ ROTR32((x),19) ^ ((x) >> 10))
/*update table P*/
#define update_P(ctx,u,v,a,b,c,d){ \
u32 tem0,tem1,tem2,tem3; \
tem0 = ROTR32((ctx->T[(v)]),23); \
tem1 = ROTR32((ctx->X[(c)]),10); \
tem2 = ROTR32((ctx->X[(b)]),8); \
h1((ctx),(ctx->X[(d)]),tem3); \
(ctx->T[(u)]) = ((ctx->T[(u)]) + tem2+(tem0^tem1)) ^ tem3; \
(ctx->X[(a)]) = (ctx->T[(u)]); \
}
/*update table Q*/
#define update_Q(ctx,u,v,a,b,c,d){ \
u32 tem0,tem1,tem2,tem3; \
tem0 = ROTR32((ctx->T[(v)]),(32-23)); \
tem1 = ROTR32((ctx->Y[(c)]),(32-10)); \
tem2 = ROTR32((ctx->Y[(b)]),(32-8)); \
h2((ctx),(ctx->Y[(d)]),tem3); \
(ctx->T[(u)]) = ((ctx->T[(u)]) + tem2+(tem0^tem1)) ^ tem3; \
(ctx->Y[(a)]) = (ctx->T[(u)]); \
}
/*16 steps of HC-128, without generating keystream, */
/*but use the outputs to update P and Q*/
void setup_update(ECRYPT_ctx* ctx) /*each time 16 steps*/
{
u32 cc,dd;
cc = ctx->counter1024 & 0x1ff;
dd = (cc+16)&0x1ff;
if (ctx->counter1024 < 512)
{
ctx->counter1024 = (ctx->counter1024 + 16) & 0x3ff;
update_P(ctx, cc+0, cc+1, 0, 6, 13, 4);
update_P(ctx, cc+1, cc+2, 1, 7, 14, 5);
update_P(ctx, cc+2, cc+3, 2, 8, 15, 6);
update_P(ctx, cc+3, cc+4, 3, 9, 0, 7);
update_P(ctx, cc+4, cc+5, 4, 10,1, 8);
update_P(ctx, cc+5, cc+6, 5, 11,2, 9);
update_P(ctx, cc+6, cc+7, 6, 12,3, 10);
update_P(ctx, cc+7, cc+8, 7, 13,4, 11);
update_P(ctx, cc+8, cc+9, 8, 14,5, 12);
update_P(ctx, cc+9, cc+10,9, 15,6, 13);
update_P(ctx, cc+10,cc+11,10,0, 7, 14);
update_P(ctx, cc+11,cc+12,11,1, 8, 15);
update_P(ctx, cc+12,cc+13,12,2, 9, 0);
update_P(ctx, cc+13,cc+14,13,3, 10, 1);
update_P(ctx, cc+14,cc+15,14,4, 11, 2);
update_P(ctx, cc+15,dd+0, 15,5, 12, 3);
}
else
{
ctx->counter1024 = (ctx->counter1024 + 16) & 0x3ff;
update_Q(ctx, 512+cc+0, 512+cc+1, 0, 6, 13, 4);
update_Q(ctx, 512+cc+1, 512+cc+2, 1, 7, 14, 5);
update_Q(ctx, 512+cc+2, 512+cc+3, 2, 8, 15, 6);
update_Q(ctx, 512+cc+3, 512+cc+4, 3, 9, 0, 7);
update_Q(ctx, 512+cc+4, 512+cc+5, 4, 10,1, 8);
update_Q(ctx, 512+cc+5, 512+cc+6, 5, 11,2, 9);
update_Q(ctx, 512+cc+6, 512+cc+7, 6, 12,3, 10);
update_Q(ctx, 512+cc+7, 512+cc+8, 7, 13,4, 11);
update_Q(ctx, 512+cc+8, 512+cc+9, 8, 14,5, 12);
update_Q(ctx, 512+cc+9, 512+cc+10,9, 15,6, 13);
update_Q(ctx, 512+cc+10,512+cc+11,10,0, 7, 14);
update_Q(ctx, 512+cc+11,512+cc+12,11,1, 8, 15);
update_Q(ctx, 512+cc+12,512+cc+13,12,2, 9, 0);
update_Q(ctx, 512+cc+13,512+cc+14,13,3, 10, 1);
update_Q(ctx, 512+cc+14,512+cc+15,14,4, 11, 2);
update_Q(ctx, 512+cc+15,512+dd+0, 15,5, 12, 3);
}
}
void ECRYPT_init(void) {
} /* No operation performed */
/* for the 128-bit key: key[0]...key[15]
* key[0] is the least significant byte of ctx->key[0] (K_0);
* key[3] is the most significant byte of ctx->key[0] (K_0);
* ...
* key[12] is the least significant byte of ctx->key[3] (K_3)
* key[15] is the most significant byte of ctx->key[3] (K_3)
*
* for the 128-bit iv: iv[0]...iv[15]
* iv[0] is the least significant byte of ctx->iv[0] (IV_0);
* iv[3] is the most significant byte of ctx->iv[0] (IV_0);
* ...
* iv[12] is the least significant byte of ctx->iv[3] (IV_3)
* iv[15] is the most significant byte of ctx->iv[3] (IV_3)
*/
void ECRYPT_keysetup(
ECRYPT_ctx* ctx,
const u8* key,
u32 keysize, /* Key size in bits (128+128*i) */
u32 ivsize) /* IV size in bits (128+128*i)*/
{
u32 i;
ctx->keysize = keysize;
ctx->ivsize = ivsize;
/* Key size in bits 128 */
for (i = 0; i < (keysize >> 5); i++) ctx->key[i] = U32TO32_LITTLE (((u32*)key)[i]);
for ( ; i < 8 ; i++) ctx->key[i] = ctx->key[i-4];
} /* initialize the key, save the iv size*/
void ECRYPT_ivsetup(ECRYPT_ctx* ctx, const u8* iv)
{
u32 i;
/* initialize the iv */
/* IV size in bits 128*/
for (i = 0; i < (ctx->ivsize >> 5); i++) ctx->iv[i] = U32TO32_LITTLE(((u32*)iv)[i]);
for (; i < 8; i++) ctx->iv[i] = ctx->iv[i-4];
/* expand the key and IV into the table T */
/* (expand the key and IV into the table P and Q) */
for (i = 0; i < 8; i++) ctx->T[i] = ctx->key[i];
for (i = 8; i < 16; i++) ctx->T[i] = ctx->iv[i-8];
for (i = 16; i < (256+16); i++)
ctx->T[i] = f2(ctx->T[i-2]) + ctx->T[i-7] + f1(ctx->T[i-15]) + ctx->T[i-16]+i;
for (i = 0; i < 16; i++) ctx->T[i] = ctx->T[256+i];
for (i = 16; i < 1024; i++)
ctx->T[i] = f2(ctx->T[i-2]) + ctx->T[i-7] + f1(ctx->T[i-15]) + ctx->T[i-16]+256+i;
/* initialize counter1024, X and Y */
ctx->counter1024 = 0;
for (i = 0; i < 16; i++) ctx->X[i] = ctx->T[512-16+i];
for (i = 0; i < 16; i++) ctx->Y[i] = ctx->T[512+512-16+i];
/* run the cipher 1024 steps before generating the output */
for (i = 0; i < 64; i++) setup_update(ctx);
}
/*========================================================
* The following defines the encryption of data stream
*========================================================
*/
void ECRYPT_process_bytes(
int action, /* 0 = encrypt; 1 = decrypt; */
ECRYPT_ctx* ctx,
const u8* input,
u8* output,
u32 msglen) /* Message length in bytes. */
{
u32 i, keystream[16];
for ( ; msglen >= 64; msglen -= 64, input += 64, output += 64)
{
generate_keystream(ctx, keystream);
/*for (i = 0; i < 16; ++i)
((u32*)output)[i] = ((u32*)input)[i] ^ U32TO32_LITTLE(keystream[i]); */
((u32*)output)[0] = ((u32*)input)[0] ^ U32TO32_LITTLE(keystream[0]);
((u32*)output)[1] = ((u32*)input)[1] ^ U32TO32_LITTLE(keystream[1]);
((u32*)output)[2] = ((u32*)input)[2] ^ U32TO32_LITTLE(keystream[2]);
((u32*)output)[3] = ((u32*)input)[3] ^ U32TO32_LITTLE(keystream[3]);
((u32*)output)[4] = ((u32*)input)[4] ^ U32TO32_LITTLE(keystream[4]);
((u32*)output)[5] = ((u32*)input)[5] ^ U32TO32_LITTLE(keystream[5]);
((u32*)output)[6] = ((u32*)input)[6] ^ U32TO32_LITTLE(keystream[6]);
((u32*)output)[7] = ((u32*)input)[7] ^ U32TO32_LITTLE(keystream[7]);
((u32*)output)[8] = ((u32*)input)[8] ^ U32TO32_LITTLE(keystream[8]);
((u32*)output)[9] = ((u32*)input)[9] ^ U32TO32_LITTLE(keystream[9]);
((u32*)output)[10] = ((u32*)input)[10] ^ U32TO32_LITTLE(keystream[10]);
((u32*)output)[11] = ((u32*)input)[11] ^ U32TO32_LITTLE(keystream[11]);
((u32*)output)[12] = ((u32*)input)[12] ^ U32TO32_LITTLE(keystream[12]);
((u32*)output)[13] = ((u32*)input)[13] ^ U32TO32_LITTLE(keystream[13]);
((u32*)output)[14] = ((u32*)input)[14] ^ U32TO32_LITTLE(keystream[14]);
((u32*)output)[15] = ((u32*)input)[15] ^ U32TO32_LITTLE(keystream[15]);
}
if (msglen > 0)
{
generate_keystream(ctx, keystream);
for (i = 0; i < msglen; i ++)
output[i] = input[i] ^ ((u8*)keystream)[i];
}
}
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