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added AES192 and 256

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This commit is contained in:
Matteo Brichese
2017-06-06 13:33:36 -07:00
parent 405f6e5eee
commit c1c5fb1974
3 changed files with 29 additions and 23 deletions
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30
aes.c
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@@ -42,6 +42,7 @@ NOTE: String length must be evenly divisible by 16byte (str_len % 16 == 0)
/*****************************************************************************/
// The number of columns comprising a state in AES. This is a constant in AES. Value=4
#define Nb 4
#define BLOCKLEN 16 //Block length in bytes AES is 128b block only
#ifdef AES256
#define Nk 8
@@ -177,7 +178,7 @@ static void KeyExpansion(void)
// All other round keys are found from the previous round keys.
//i == Nk
for(i = Nk; i < Nb * (Nr + 1); ++i)
for(; i < Nb * (Nr + 1); ++i)
{
{
tempa[0]=RoundKey[(i-1) * 4 + 0];
@@ -494,7 +495,7 @@ void AES_ECB_decrypt(const uint8_t* input, const uint8_t* key, uint8_t *output,
static void XorWithIv(uint8_t* buf)
{
uint8_t i;
for(i = 0; i < 16; ++i) //WAS for(i = 0; i < KEYLEN; ++i) but the block in AES is always 128bit so 16 bytes!
for(i = 0; i < BLOCKLEN; ++i) //WAS for(i = 0; i < KEYLEN; ++i) but the block in AES is always 128bit so 16 bytes!
{
buf[i] ^= Iv[i];
}
@@ -503,9 +504,9 @@ static void XorWithIv(uint8_t* buf)
void AES_CBC_encrypt_buffer(uint8_t* output, uint8_t* input, uint32_t length, const uint8_t* key, const uint8_t* iv)
{
uintptr_t i;
uint8_t extra = length % 16; /* Remaining bytes in the last non-full block */
uint8_t extra = length % BLOCKLEN; /* Remaining bytes in the last non-full block */
memcpy(output, input, 16);
memcpy(output, input, BLOCKLEN);
state = (state_t*)output;
// Skip the key expansion if key is passed as 0
@@ -520,21 +521,20 @@ void AES_CBC_encrypt_buffer(uint8_t* output, uint8_t* input, uint32_t length, co
Iv = (uint8_t*)iv;
}
for(i = 0; i < length; i += 16)
for(i = 0; i < length; i += BLOCKLEN)
{
XorWithIv(input);
memcpy(output, input, 16);
memcpy(output, input, BLOCKLEN);
state = (state_t*)output;
Cipher();
Iv = output;
input += 16;
output += 16;
input += BLOCKLEN;
output += BLOCKLEN;
//printf("Step %d - %d", i/16, i);
}
if(extra)
{
printf("NONO\n");
memcpy(output, input, extra);
state = (state_t*)output;
Cipher();
@@ -544,9 +544,9 @@ void AES_CBC_encrypt_buffer(uint8_t* output, uint8_t* input, uint32_t length, co
void AES_CBC_decrypt_buffer(uint8_t* output, uint8_t* input, uint32_t length, const uint8_t* key, const uint8_t* iv)
{
uintptr_t i;
uint8_t extra = length % 16; /* Remaining bytes in the last non-full block */
uint8_t extra = length % BLOCKLEN; /* Remaining bytes in the last non-full block */
memcpy(output, input, 16);
memcpy(output, input, BLOCKLEN);
state = (state_t*)output;
// Skip the key expansion if key is passed as 0
@@ -562,15 +562,15 @@ void AES_CBC_decrypt_buffer(uint8_t* output, uint8_t* input, uint32_t length, co
Iv = (uint8_t*)iv;
}
for(i = 0; i < length; i += 16)
for(i = 0; i < length; i += BLOCKLEN)
{
memcpy(output, input, 16);
memcpy(output, input, BLOCKLEN);
state = (state_t*)output;
InvCipher();
XorWithIv(output);
Iv = input;
input += 16;
output += 16;
input += BLOCKLEN;
output += BLOCKLEN;
}
if(extra)