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-rw-r--r--aes.c189
1 files changed, 103 insertions, 86 deletions
diff --git a/aes.c b/aes.c
index cceaad0..a836059 100644
--- a/aes.c
+++ b/aes.c
@@ -60,7 +60,9 @@ NOTE: String length must be evenly divisible by 16byte (str_len % 16 == 0)
// in - pointer to the CipherText to be decrypted.
// out - pointer to buffer to hold output of the decryption.
// state - array holding the intermediate results during decryption.
-static uint8_t* in, *out, state[4][4];
+//static uint8_t* in, *out, state[4][4];
+typedef uint8_t state_t[4][4];
+static state_t* state;
// The array that stores the round keys.
static uint8_t RoundKey[176];
@@ -219,7 +221,7 @@ static void AddRoundKey(uint8_t round)
{
for(j = 0; j < 4; ++j)
{
- state[j][i] ^= RoundKey[round * Nb * 4 + i * Nb + j];
+ (*state)[i][j] ^= RoundKey[round * Nb * 4 + i * Nb + j];
}
}
}
@@ -233,7 +235,7 @@ static void SubBytes(void)
{
for(j = 0; j < 4; ++j)
{
- state[i][j] = getSBoxValue(state[i][j]);
+ (*state)[j][i] = getSBoxValue((*state)[j][i]);
}
}
}
@@ -246,27 +248,27 @@ static void ShiftRows(void)
uint8_t temp;
// Rotate first row 1 columns to left
- temp = state[1][0];
- state[1][0] = state[1][1];
- state[1][1] = state[1][2];
- state[1][2] = state[1][3];
- state[1][3] = temp;
+ temp = (*state)[0][1];
+ (*state)[0][1] = (*state)[1][1];
+ (*state)[1][1] = (*state)[2][1];
+ (*state)[2][1] = (*state)[3][1];
+ (*state)[3][1] = temp;
// Rotate second row 2 columns to left
- temp = state[2][0];
- state[2][0] = state[2][2];
- state[2][2] = temp;
+ temp = (*state)[0][2];
+ (*state)[0][2] = (*state)[2][2];
+ (*state)[2][2] = temp;
- temp = state[2][1];
- state[2][1] = state[2][3];
- state[2][3] = temp;
+ temp = (*state)[1][2];
+ (*state)[1][2] = (*state)[3][2];
+ (*state)[3][2] = temp;
// Rotate third row 3 columns to left
- temp = state[3][0];
- state[3][0] = state[3][3];
- state[3][3] = state[3][2];
- state[3][2] = state[3][1];
- state[3][1] = temp;
+ temp = (*state)[0][3];
+ (*state)[0][3] = (*state)[3][3];
+ (*state)[3][3] = (*state)[2][3];
+ (*state)[2][3] = (*state)[1][3];
+ (*state)[1][3] = temp;
}
static uint8_t xtime(uint8_t x)
@@ -281,12 +283,12 @@ static void MixColumns(void)
uint8_t Tmp,Tm,t;
for(i = 0; i < 4; ++i)
{
- t = state[0][i];
- Tmp = state[0][i] ^ state[1][i] ^ state[2][i] ^ state[3][i] ;
- Tm = state[0][i] ^ state[1][i] ; Tm = xtime(Tm); state[0][i] ^= Tm ^ Tmp ;
- Tm = state[1][i] ^ state[2][i] ; Tm = xtime(Tm); state[1][i] ^= Tm ^ Tmp ;
- Tm = state[2][i] ^ state[3][i] ; Tm = xtime(Tm); state[2][i] ^= Tm ^ Tmp ;
- Tm = state[3][i] ^ t ; Tm = xtime(Tm); state[3][i] ^= Tm ^ Tmp ;
+ t = (*state)[i][0];
+ Tmp = (*state)[i][0] ^ (*state)[i][1] ^ (*state)[i][2] ^ (*state)[i][3] ;
+ Tm = (*state)[i][0] ^ (*state)[i][1] ; Tm = xtime(Tm); (*state)[i][0] ^= Tm ^ Tmp ;
+ Tm = (*state)[i][1] ^ (*state)[i][2] ; Tm = xtime(Tm); (*state)[i][1] ^= Tm ^ Tmp ;
+ Tm = (*state)[i][2] ^ (*state)[i][3] ; Tm = xtime(Tm); (*state)[i][2] ^= Tm ^ Tmp ;
+ Tm = (*state)[i][3] ^ t ; Tm = xtime(Tm); (*state)[i][3] ^= Tm ^ Tmp ;
}
}
@@ -322,16 +324,16 @@ static void InvMixColumns(void)
for(i=0;i<4;++i)
{
- a = state[0][i];
- b = state[1][i];
- c = state[2][i];
- d = state[3][i];
+ a = (*state)[i][0];
+ b = (*state)[i][1];
+ c = (*state)[i][2];
+ d = (*state)[i][3];
- state[0][i] = Multiply(a, 0x0e) ^ Multiply(b, 0x0b) ^ Multiply(c, 0x0d) ^ Multiply(d, 0x09);
- state[1][i] = Multiply(a, 0x09) ^ Multiply(b, 0x0e) ^ Multiply(c, 0x0b) ^ Multiply(d, 0x0d);
- state[2][i] = Multiply(a, 0x0d) ^ Multiply(b, 0x09) ^ Multiply(c, 0x0e) ^ Multiply(d, 0x0b);
- state[3][i] = Multiply(a, 0x0b) ^ Multiply(b, 0x0d) ^ Multiply(c, 0x09) ^ Multiply(d, 0x0e);
+ (*state)[i][0] = Multiply(a, 0x0e) ^ Multiply(b, 0x0b) ^ Multiply(c, 0x0d) ^ Multiply(d, 0x09);
+ (*state)[i][1] = Multiply(a, 0x09) ^ Multiply(b, 0x0e) ^ Multiply(c, 0x0b) ^ Multiply(d, 0x0d);
+ (*state)[i][2] = Multiply(a, 0x0d) ^ Multiply(b, 0x09) ^ Multiply(c, 0x0e) ^ Multiply(d, 0x0b);
+ (*state)[i][3] = Multiply(a, 0x0b) ^ Multiply(b, 0x0d) ^ Multiply(c, 0x09) ^ Multiply(d, 0x0e);
}
}
@@ -345,7 +347,7 @@ static void InvSubBytes(void)
{
for(j=0;j<4;++j)
{
- state[i][j] = getSBoxInvert(state[i][j]);
+ (*state)[j][i] = getSBoxInvert((*state)[j][i]);
}
}
}
@@ -355,43 +357,44 @@ static void InvShiftRows(void)
uint8_t temp;
// Rotate first row 1 columns to right
- temp=state[1][3];
- state[1][3]=state[1][2];
- state[1][2]=state[1][1];
- state[1][1]=state[1][0];
- state[1][0]=temp;
+ temp=(*state)[3][1];
+ (*state)[3][1]=(*state)[2][1];
+ (*state)[2][1]=(*state)[1][1];
+ (*state)[1][1]=(*state)[0][1];
+ (*state)[0][1]=temp;
// Rotate second row 2 columns to right
- temp=state[2][0];
- state[2][0]=state[2][2];
- state[2][2]=temp;
+ temp=(*state)[0][2];
+ (*state)[0][2]=(*state)[2][2];
+ (*state)[2][2]=temp;
- temp=state[2][1];
- state[2][1]=state[2][3];
- state[2][3]=temp;
+ temp=(*state)[1][2];
+ (*state)[1][2]=(*state)[3][2];
+ (*state)[3][2]=temp;
// Rotate third row 3 columns to right
- temp=state[3][0];
- state[3][0]=state[3][1];
- state[3][1]=state[3][2];
- state[3][2]=state[3][3];
- state[3][3]=temp;
+ temp=(*state)[0][3];
+ (*state)[0][3]=(*state)[1][3];
+ (*state)[1][3]=(*state)[2][3];
+ (*state)[2][3]=(*state)[3][3];
+ (*state)[3][3]=temp;
}
// Cipher is the main function that encrypts the PlainText.
static void Cipher(void)
{
- uint8_t i, j, round = 0;
+ //uint8_t i, j,
+ uint8_t round = 0;
// Copy the input PlainText to state array.
- for(i = 0; i < 4; ++i)
- {
- for(j = 0; j < 4 ; ++j)
- {
- state[j][i] = in[(i * 4) + j];
- }
- }
+// for(i = 0; i < 4; ++i)
+// {
+// for(j = 0; j < 4 ; ++j)
+// {
+// (*state)[i][j] = in[(i * 4) + j];
+// }
+// }
// Add the First round key to the state before starting the rounds.
AddRoundKey(0);
@@ -415,27 +418,28 @@ static void Cipher(void)
// The encryption process is over.
// Copy the state array to output array.
- for(i = 0; i < 4; ++i)
- {
- for(j = 0; j < 4; ++j)
- {
- out[(i * 4) + j] = state[j][i];
- }
- }
+// for(i = 0; i < 4; ++i)
+// {
+// for(j = 0; j < 4; ++j)
+// {
+// out[(i * 4) + j] = (*state)[i][j];
+// }
+// }
}
static void InvCipher(void)
{
- uint8_t i,j,round=0;
+ //uint8_t i,j,
+ uint8_t round=0;
// Copy the input CipherText to state array.
- for(i=0;i<4;++i)
- {
- for(j=0;j<4;++j)
- {
- state[j][i] = in[i*4 + j];
- }
- }
+// for(i=0;i<4;++i)
+// {
+// for(j=0;j<4;++j)
+// {
+// (*state)[i][j] = in[i*4 + j];
+// }
+// }
// Add the First round key to the state before starting the rounds.
AddRoundKey(Nr);
@@ -459,13 +463,13 @@ static void InvCipher(void)
// The decryption process is over.
// Copy the state array to output array.
- for(i=0;i<4;++i)
- {
- for(j=0;j<4;++j)
- {
- out[i*4+j]=state[j][i];
- }
- }
+// for(i=0;i<4;++i)
+// {
+// for(j=0;j<4;++j)
+// {
+// out[i*4+j]=(*state)[i][j];
+// }
+// }
}
@@ -473,12 +477,11 @@ static void InvCipher(void)
/* Public functions: */
/*****************************************************************************/
-void AES128_ECB_encrypt(uint8_t* input, const uint8_t* key, uint8_t *output)
+void AES128_ECB_encrypt_nc(uint8_t* data, const uint8_t* key)
{
// Copy the Key and CipherText
Key = key;
- in = input;
- out = output;
+ state = (state_t*)data;
// The KeyExpansion routine must be called before encryption.
KeyExpansion();
@@ -487,14 +490,28 @@ void AES128_ECB_encrypt(uint8_t* input, const uint8_t* key, uint8_t *output)
Cipher();
}
-void AES128_ECB_decrypt(uint8_t* input, const uint8_t* key, uint8_t *output)
+void AES128_ECB_decrypt_nc(uint8_t* data, const uint8_t* key)
{
Key = key;
- in = input;
- out = output;
+ state = (state_t*)data;
KeyExpansion();
InvCipher();
}
+void AES128_ECB_encrypt(uint8_t* input, const uint8_t* key, uint8_t *output)
+{
+ uint8_t i;
+ for (i=0;i<16;++i)
+ output[i] = input[i];
+ AES128_ECB_encrypt_nc(output, key);
+}
+
+void AES128_ECB_decrypt(uint8_t* input, const uint8_t* key, uint8_t *output)
+{
+ uint8_t i;
+ for (i=0;i<16;++i)
+ output[i] = input[i];
+ AES128_ECB_decrypt_nc(output, key);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-10 05:08:51 +0100