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inplace api and test, Makefile update

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This commit is contained in:
Stoian Ivanov
2017-12-05 14:27:53 +02:00
parent 88f258872c
commit 1e86fddb21
4 changed files with 69 additions and 75 deletions
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68
aes.c
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@@ -482,21 +482,16 @@ static void InvCipher(state_t *state,uint8_t*RoundKey)
#if defined(ECB) && (ECB == 1)
void AES_ECB_encrypt(struct AES_ctx *ctx,const uint8_t* input, uint8_t* output)
void AES_ECB_encrypt(struct AES_ctx *ctx,const uint8_t* buf)
{
// Copy input to output, and work in-memory on output
memcpy(output, input, AES_BLOCKLEN);
// The next function call encrypts the PlainText with the Key using AES algorithm.
Cipher((state_t*)output,ctx->RoundKey);
Cipher((state_t*)buf,ctx->RoundKey);
}
void AES_ECB_decrypt(struct AES_ctx *ctx,const uint8_t* input, uint8_t *output)
void AES_ECB_decrypt(struct AES_ctx *ctx,const uint8_t* buf)
{
// Copy input to output, and work in-memory on output
memcpy(output, input, AES_BLOCKLEN);
InvCipher((state_t*)output,ctx->RoundKey);
// The next function call decrypts the PlainText with the Key using AES algorithm.
InvCipher((state_t*)buf,ctx->RoundKey);
}
@@ -518,35 +513,33 @@ static void XorWithIv(uint8_t* buf,uint8_t*Iv)
}
}
void AES_CBC_encrypt_buffer(struct AES_ctx *ctx,uint8_t* output, uint8_t* input, uint32_t length)
void AES_CBC_encrypt_buffer(struct AES_ctx *ctx,uint8_t* buf, uint32_t length)
{
uintptr_t i;
uint8_t *Iv=ctx->Iv;
memcpy(output, input, length);
for (i = 0; i < length; i += AES_BLOCKLEN)
{
XorWithIv(output,Iv);
Cipher((state_t*)output,ctx->RoundKey);
Iv = output;
output += AES_BLOCKLEN;
XorWithIv(buf,Iv);
Cipher((state_t*)buf,ctx->RoundKey);
Iv = buf;
buf += AES_BLOCKLEN;
//printf("Step %d - %d", i/16, i);
}
//store Iv in ctx for next call
memcpy(ctx->Iv,Iv,AES_BLOCKLEN);
}
void AES_CBC_decrypt_buffer(struct AES_ctx *ctx, uint8_t* output, uint8_t* input, uint32_t length)
void AES_CBC_decrypt_buffer(struct AES_ctx *ctx, uint8_t* buf, uint32_t length)
{
uintptr_t i;
uint8_t *Iv=ctx->Iv;
memcpy(output, input, length);
uint8_t storeNextIv[AES_BLOCKLEN];
for (i = 0; i < length; i += AES_BLOCKLEN)
{
InvCipher((state_t*)output,ctx->RoundKey);
XorWithIv(output,Iv);
Iv = input; //we DO need original input stored here
input += AES_BLOCKLEN;
output += AES_BLOCKLEN;
memcpy(storeNextIv, buf, AES_BLOCKLEN);
InvCipher((state_t*)buf,ctx->RoundKey);
XorWithIv(buf,ctx->Iv);
memcpy(ctx->Iv, storeNextIv, AES_BLOCKLEN);
buf += AES_BLOCKLEN;
}
}
@@ -558,34 +551,35 @@ void AES_CBC_decrypt_buffer(struct AES_ctx *ctx, uint8_t* output, uint8_t* input
#if defined(CTR) && (CTR == 1)
/* Symmetrical operation: same function for encrypting as for decrypting. Note any IV/nonce should never be reused with the same key */
void AES_CTR_xcrypt_buffer(struct AES_ctx *ctx,uint8_t* output, uint8_t* input, uint32_t length)
void AES_CTR_xcrypt_buffer(struct AES_ctx* ctx, uint8_t* buf, uint32_t length)
{
uint8_t buffer[AES_BLOCKLEN];
int j;
unsigned i;
for (i = 0; i < length; ++i)
int bi;
for (i = 0,bi=AES_BLOCKLEN; i < length; ++i,bi++)
{
if ((i & (AES_BLOCKLEN - 1)) == 0) //we need to regen xor compliment in buff
if (bi == AES_BLOCKLEN) //we need to regen xor compliment in buffer
{
memcpy(buffer, ctx->Iv, AES_BLOCKLEN);
Cipher((state_t*)buffer,ctx->RoundKey);
/* Increment counter and handle overflow */
for (j = (AES_BLOCKLEN - 1); j >= 0; --j)
/* Increment Iv and handle overflow */
for (bi = (AES_BLOCKLEN - 1); bi >= 0; --bi)
{
ctx->Iv[j] += 1;
if (ctx->Iv[bi] == 255) { //inc will owerflow
ctx->Iv[bi]=0;
continue;
}
ctx->Iv[bi] += 1;
break;
/* Break if no overflow, keep going otherwise */
if (ctx->Iv[j] != 0)
{
break;
}
}
bi=0;
}
output[i] = (input[i] ^ buffer[(i & (AES_BLOCKLEN - 1))]);
buf[i] = (buf[i] ^ buffer[bi]);
}
}