mirror of
https://github.com/kokke/tiny-AES-c
synced 2024-11-22 05:21:52 +03:00
make thead safe via context pram; remove padding as non working; opitmise abit
This commit is contained in:
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247
aes.c
247
aes.c
@ -44,23 +44,16 @@ NOTE: String length must be evenly divisible by 16byte (str_len % 16 == 0)
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/*****************************************************************************/
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/*****************************************************************************/
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// The number of columns comprising a state in AES. This is a constant in AES. Value=4
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// The number of columns comprising a state in AES. This is a constant in AES. Value=4
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#define Nb 4
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#define Nb 4
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#define BLOCKLEN 16 //Block length in bytes AES is 128b block only
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#if defined(AES256) && (AES256 == 1)
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#if defined(AES256) && (AES256 == 1)
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#define Nk 8
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#define Nk 8
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#define KEYLEN 32
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#define Nr 14
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#define Nr 14
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#define keyExpSize 240
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#elif defined(AES192) && (AES192 == 1)
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#elif defined(AES192) && (AES192 == 1)
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#define Nk 6
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#define Nk 6
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#define KEYLEN 24
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#define Nr 12
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#define Nr 12
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#define keyExpSize 208
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#else
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#else
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#define Nk 4 // The number of 32 bit words in a key.
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#define Nk 4 // The number of 32 bit words in a key.
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#define KEYLEN 16 // Key length in bytes
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#define Nr 10 // The number of rounds in AES Cipher.
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#define Nr 10 // The number of rounds in AES Cipher.
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#define keyExpSize 176
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#endif
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#endif
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// jcallan@github points out that declaring Multiply as a function
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// jcallan@github points out that declaring Multiply as a function
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@ -71,23 +64,17 @@ NOTE: String length must be evenly divisible by 16byte (str_len % 16 == 0)
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#endif
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#endif
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/*****************************************************************************/
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/*****************************************************************************/
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/* Private variables: */
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/* Private variables: */
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/*****************************************************************************/
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/*****************************************************************************/
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// state - array holding the intermediate results during decryption.
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// state - array holding the intermediate results during decryption.
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typedef uint8_t state_t[4][4];
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typedef uint8_t state_t[4][4];
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static state_t* state;
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// The array that stores the round keys.
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static uint8_t RoundKey[keyExpSize];
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// The Key input to the AES Program
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static const uint8_t* Key;
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#if defined(CBC) && CBC
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// Initial Vector used only for CBC mode
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static uint8_t* Iv;
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#endif
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// The lookup-tables are marked const so they can be placed in read-only storage instead of RAM
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// The lookup-tables are marked const so they can be placed in read-only storage instead of RAM
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// The numbers below can be computed dynamically trading ROM for RAM -
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// The numbers below can be computed dynamically trading ROM for RAM -
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@ -168,23 +155,30 @@ static const uint8_t Rcon[256] = {
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/*****************************************************************************/
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/*****************************************************************************/
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/* Private functions: */
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/* Private functions: */
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/*****************************************************************************/
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/*****************************************************************************/
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/*
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static uint8_t getSBoxValue(uint8_t num)
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static uint8_t getSBoxValue(uint8_t num)
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{
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{
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return sbox[num];
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return sbox[num];
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}
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}
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*/
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#define getSBoxValue(num) (sbox[(num)])
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/*
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static uint8_t getSBoxInvert(uint8_t num)
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static uint8_t getSBoxInvert(uint8_t num)
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{
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{
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return rsbox[num];
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return rsbox[num];
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}
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}
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*/
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#define getSBoxInvert(num) (rsbox[(num)])
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// This function produces Nb(Nr+1) round keys. The round keys are used in each round to decrypt the states.
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// This function produces Nb(Nr+1) round keys. The round keys are used in each round to decrypt the states.
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static void KeyExpansion(void)
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static void KeyExpansion(uint8_t* RoundKey,const uint8_t* Key)
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{
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{
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uint32_t i, k;
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unsigned i, j, k;
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uint8_t tempa[4]; // Used for the column/row operations
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uint8_t tempa[4]; // Used for the column/row operations
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// The first round key is the key itself.
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// The first round key is the key itself.
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memcpy(RoundKey,Key,AES_keyExpSize);
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/*
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for (i = 0; i < Nk; ++i)
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for (i = 0; i < Nk; ++i)
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{
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{
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RoundKey[(i * 4) + 0] = Key[(i * 4) + 0];
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RoundKey[(i * 4) + 0] = Key[(i * 4) + 0];
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@ -192,16 +186,17 @@ static void KeyExpansion(void)
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RoundKey[(i * 4) + 2] = Key[(i * 4) + 2];
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RoundKey[(i * 4) + 2] = Key[(i * 4) + 2];
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RoundKey[(i * 4) + 3] = Key[(i * 4) + 3];
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RoundKey[(i * 4) + 3] = Key[(i * 4) + 3];
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}
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}
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*/
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// All other round keys are found from the previous round keys.
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// All other round keys are found from the previous round keys.
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//i == Nk
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for (i = Nk; i < Nb * (Nr + 1); ++i)
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for (; i < Nb * (Nr + 1); ++i)
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{
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{
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{
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{
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tempa[0]=RoundKey[(i-1) * 4 + 0];
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k=(i-1) * 4;
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tempa[1]=RoundKey[(i-1) * 4 + 1];
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tempa[0]=RoundKey[k + 0];
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tempa[2]=RoundKey[(i-1) * 4 + 2];
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tempa[1]=RoundKey[k + 1];
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tempa[3]=RoundKey[(i-1) * 4 + 3];
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tempa[2]=RoundKey[k + 2];
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tempa[3]=RoundKey[k + 3];
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}
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}
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if (i % Nk == 0)
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if (i % Nk == 0)
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@ -243,16 +238,30 @@ static void KeyExpansion(void)
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}
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}
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}
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}
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#endif
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#endif
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RoundKey[i * 4 + 0] = RoundKey[(i - Nk) * 4 + 0] ^ tempa[0];
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j=i * 4; k=(i - Nk) * 4;
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RoundKey[i * 4 + 1] = RoundKey[(i - Nk) * 4 + 1] ^ tempa[1];
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RoundKey[j + 0] = RoundKey[k + 0] ^ tempa[0];
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RoundKey[i * 4 + 2] = RoundKey[(i - Nk) * 4 + 2] ^ tempa[2];
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RoundKey[j + 1] = RoundKey[k + 1] ^ tempa[1];
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RoundKey[i * 4 + 3] = RoundKey[(i - Nk) * 4 + 3] ^ tempa[3];
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RoundKey[j + 2] = RoundKey[k + 2] ^ tempa[2];
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RoundKey[j + 3] = RoundKey[k + 3] ^ tempa[3];
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}
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}
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}
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}
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void AES_init_ctx(struct AES_ctx *ctx,const uint8_t* key){
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KeyExpansion(ctx->RoundKey,key);
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}
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#if defined(CBC) && (CBC == 1)
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void AES_init_ctx_iv(struct AES_ctx *ctx,const uint8_t* key,const uint8_t* iv){
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KeyExpansion(ctx->RoundKey,key);
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memcpy (ctx->Iv,iv,AES_BLOCKLEN);
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}
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void AES_ctx_set_iv(struct AES_ctx *ctx,const uint8_t* iv) {
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memcpy (ctx->Iv,iv,AES_BLOCKLEN);
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}
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#endif
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// This function adds the round key to state.
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// This function adds the round key to state.
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// The round key is added to the state by an XOR function.
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// The round key is added to the state by an XOR function.
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static void AddRoundKey(uint8_t round)
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static void AddRoundKey(uint8_t round,state_t *state,uint8_t*RoundKey)
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{
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{
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uint8_t i,j;
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uint8_t i,j;
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for (i=0;i<4;++i)
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for (i=0;i<4;++i)
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@ -266,7 +275,7 @@ static void AddRoundKey(uint8_t round)
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// The SubBytes Function Substitutes the values in the
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// The SubBytes Function Substitutes the values in the
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// state matrix with values in an S-box.
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// state matrix with values in an S-box.
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static void SubBytes(void)
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static void SubBytes(state_t *state)
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{
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{
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uint8_t i, j;
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uint8_t i, j;
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for (i = 0; i < 4; ++i)
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for (i = 0; i < 4; ++i)
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@ -281,7 +290,7 @@ static void SubBytes(void)
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// The ShiftRows() function shifts the rows in the state to the left.
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// The ShiftRows() function shifts the rows in the state to the left.
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// Each row is shifted with different offset.
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// Each row is shifted with different offset.
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// Offset = Row number. So the first row is not shifted.
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// Offset = Row number. So the first row is not shifted.
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static void ShiftRows(void)
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static void ShiftRows(state_t *state)
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{
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{
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uint8_t temp;
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uint8_t temp;
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@ -315,7 +324,7 @@ static uint8_t xtime(uint8_t x)
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}
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}
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// MixColumns function mixes the columns of the state matrix
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// MixColumns function mixes the columns of the state matrix
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static void MixColumns(void)
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static void MixColumns(state_t *state)
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{
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{
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uint8_t i;
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uint8_t i;
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uint8_t Tmp,Tm,t;
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uint8_t Tmp,Tm,t;
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@ -353,7 +362,7 @@ static uint8_t Multiply(uint8_t x, uint8_t y)
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// MixColumns function mixes the columns of the state matrix.
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// MixColumns function mixes the columns of the state matrix.
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// The method used to multiply may be difficult to understand for the inexperienced.
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// The method used to multiply may be difficult to understand for the inexperienced.
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// Please use the references to gain more information.
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// Please use the references to gain more information.
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static void InvMixColumns(void)
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static void InvMixColumns(state_t *state)
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{
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{
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int i;
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int i;
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uint8_t a, b, c, d;
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uint8_t a, b, c, d;
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@ -374,7 +383,7 @@ static void InvMixColumns(void)
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// The SubBytes Function Substitutes the values in the
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// The SubBytes Function Substitutes the values in the
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// state matrix with values in an S-box.
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// state matrix with values in an S-box.
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static void InvSubBytes(void)
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static void InvSubBytes(state_t *state)
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{
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{
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uint8_t i,j;
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uint8_t i,j;
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for (i = 0; i < 4; ++i)
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for (i = 0; i < 4; ++i)
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@ -386,7 +395,7 @@ static void InvSubBytes(void)
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}
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}
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}
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}
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static void InvShiftRows(void)
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static void InvShiftRows(state_t *state)
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{
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{
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uint8_t temp;
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uint8_t temp;
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@ -416,54 +425,54 @@ static void InvShiftRows(void)
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// Cipher is the main function that encrypts the PlainText.
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// Cipher is the main function that encrypts the PlainText.
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static void Cipher(void)
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static void Cipher(state_t *state,uint8_t*RoundKey)
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{
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{
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uint8_t round = 0;
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uint8_t round = 0;
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// Add the First round key to the state before starting the rounds.
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// Add the First round key to the state before starting the rounds.
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AddRoundKey(0);
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AddRoundKey(0,state,RoundKey);
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// There will be Nr rounds.
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// There will be Nr rounds.
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// The first Nr-1 rounds are identical.
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// The first Nr-1 rounds are identical.
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// These Nr-1 rounds are executed in the loop below.
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// These Nr-1 rounds are executed in the loop below.
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for (round = 1; round < Nr; ++round)
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for (round = 1; round < Nr; ++round)
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{
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{
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SubBytes();
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SubBytes(state);
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ShiftRows();
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ShiftRows(state);
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MixColumns();
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MixColumns(state);
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AddRoundKey(round);
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AddRoundKey(round,state,RoundKey);
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}
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}
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// The last round is given below.
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// The last round is given below.
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// The MixColumns function is not here in the last round.
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// The MixColumns function is not here in the last round.
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SubBytes();
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SubBytes(state);
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ShiftRows();
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ShiftRows(state);
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AddRoundKey(Nr);
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AddRoundKey(Nr,state,RoundKey);
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}
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}
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static void InvCipher(void)
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static void InvCipher(state_t *state,uint8_t*RoundKey)
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{
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{
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uint8_t round=0;
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uint8_t round=0;
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// Add the First round key to the state before starting the rounds.
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// Add the First round key to the state before starting the rounds.
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AddRoundKey(Nr);
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AddRoundKey(Nr,state,RoundKey);
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// There will be Nr rounds.
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// There will be Nr rounds.
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// The first Nr-1 rounds are identical.
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// The first Nr-1 rounds are identical.
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// These Nr-1 rounds are executed in the loop below.
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// These Nr-1 rounds are executed in the loop below.
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for (round = (Nr - 1); round > 0; --round)
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for (round = (Nr - 1); round > 0; --round)
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{
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{
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InvShiftRows();
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InvShiftRows(state);
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InvSubBytes();
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InvSubBytes(state);
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AddRoundKey(round);
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AddRoundKey(round,state,RoundKey);
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InvMixColumns();
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InvMixColumns(state);
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}
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}
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// The last round is given below.
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// The last round is given below.
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// The MixColumns function is not here in the last round.
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// The MixColumns function is not here in the last round.
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InvShiftRows();
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InvShiftRows(state);
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InvSubBytes();
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InvSubBytes(state);
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AddRoundKey(0);
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AddRoundKey(0,state,RoundKey);
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}
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}
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@ -473,30 +482,21 @@ static void InvCipher(void)
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#if defined(ECB) && (ECB == 1)
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#if defined(ECB) && (ECB == 1)
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void AES_ECB_encrypt(const uint8_t* input, const uint8_t* key, uint8_t* output, const uint32_t length)
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void AES_ECB_encrypt(struct AES_ctx *ctx,const uint8_t* input, uint8_t* output)
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{
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{
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// Copy input to output, and work in-memory on output
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// Copy input to output, and work in-memory on output
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memcpy(output, input, length);
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memcpy(output, input, AES_BLOCKLEN);
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state = (state_t*)output;
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Key = key;
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KeyExpansion();
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// The next function call encrypts the PlainText with the Key using AES algorithm.
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// The next function call encrypts the PlainText with the Key using AES algorithm.
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Cipher();
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Cipher((state_t*)output,ctx->RoundKey);
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}
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}
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void AES_ECB_decrypt(const uint8_t* input, const uint8_t* key, uint8_t *output, const uint32_t length)
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void AES_ECB_decrypt(struct AES_ctx *ctx,const uint8_t* input, uint8_t *output)
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{
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{
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// Copy input to output, and work in-memory on output
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// Copy input to output, and work in-memory on output
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memcpy(output, input, length);
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memcpy(output, input, AES_BLOCKLEN);
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state = (state_t*)output;
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InvCipher((state_t*)output,ctx->RoundKey);
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// The KeyExpansion routine must be called before encryption.
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Key = key;
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KeyExpansion();
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InvCipher();
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}
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}
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@ -509,89 +509,46 @@ void AES_ECB_decrypt(const uint8_t* input, const uint8_t* key, uint8_t *output,
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#if defined(CBC) && (CBC == 1)
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#if defined(CBC) && (CBC == 1)
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static void XorWithIv(uint8_t* buf)
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static void XorWithIv(uint8_t* buf,uint8_t*Iv)
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{
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{
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uint8_t i;
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uint8_t i;
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for (i = 0; i < BLOCKLEN; ++i) //WAS for(i = 0; i < KEYLEN; ++i) but the block in AES is always 128bit so 16 bytes!
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for (i = 0; i < AES_BLOCKLEN; ++i) //WAS for(i = 0; i < KEYLEN; ++i) but the block in AES is always 128bit so 16 bytes!
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{
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{
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buf[i] ^= Iv[i];
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buf[i] ^= Iv[i];
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}
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}
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}
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}
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void AES_CBC_encrypt_buffer(uint8_t* output, uint8_t* input, uint32_t length, const uint8_t* key, const uint8_t* iv)
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void AES_CBC_encrypt_buffer(struct AES_ctx *ctx,uint8_t* output, uint8_t* input, uint32_t length)
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{
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{
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uintptr_t i;
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uintptr_t i;
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uint8_t extra = length % BLOCKLEN; /* Remaining bytes in the last non-full block */
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uint8_t *Iv=ctx->Iv;
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memcpy(output, input, length);
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// Skip the key expansion if key is passed as 0
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for (i = 0; i < length; i += AES_BLOCKLEN)
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if (0 != key)
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{
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{
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Key = key;
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XorWithIv(output,Iv);
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KeyExpansion();
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Cipher((state_t*)output,ctx->RoundKey);
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}
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|
|
||||||
if (iv != 0)
|
|
||||||
{
|
|
||||||
Iv = (uint8_t*)iv;
|
|
||||||
}
|
|
||||||
|
|
||||||
for (i = 0; i < length; i += BLOCKLEN)
|
|
||||||
{
|
|
||||||
memcpy(output, input, BLOCKLEN);
|
|
||||||
XorWithIv(output);
|
|
||||||
state = (state_t*)output;
|
|
||||||
Cipher();
|
|
||||||
Iv = output;
|
Iv = output;
|
||||||
input += BLOCKLEN;
|
output += AES_BLOCKLEN;
|
||||||
output += BLOCKLEN;
|
|
||||||
//printf("Step %d - %d", i/16, i);
|
//printf("Step %d - %d", i/16, i);
|
||||||
}
|
}
|
||||||
|
//store Iv in ctx for next call
|
||||||
if (extra)
|
memcpy(ctx->Iv,Iv,AES_BLOCKLEN);
|
||||||
{
|
|
||||||
memcpy(output, input, extra);
|
|
||||||
memset((output + extra), 0, (BLOCKLEN - extra));
|
|
||||||
XorWithIv(output);
|
|
||||||
state = (state_t*)output;
|
|
||||||
Cipher();
|
|
||||||
}
|
|
||||||
}
|
}
|
||||||
|
|
||||||
void AES_CBC_decrypt_buffer(uint8_t* output, uint8_t* input, uint32_t length, const uint8_t* key, const uint8_t* iv)
|
void AES_CBC_decrypt_buffer(struct AES_ctx *ctx, uint8_t* output, uint8_t* input, uint32_t length)
|
||||||
{
|
{
|
||||||
uintptr_t i;
|
uintptr_t i;
|
||||||
uint8_t extra = length % BLOCKLEN; /* Remaining bytes in the last non-full block */
|
uint8_t *Iv=ctx->Iv;
|
||||||
|
memcpy(output, input, length);
|
||||||
// Skip the key expansion if key is passed as 0
|
for (i = 0; i < length; i += AES_BLOCKLEN)
|
||||||
if (0 != key)
|
|
||||||
{
|
{
|
||||||
Key = key;
|
InvCipher((state_t*)output,ctx->RoundKey);
|
||||||
KeyExpansion();
|
XorWithIv(output,Iv);
|
||||||
|
Iv = input; //we DO need original input stored here
|
||||||
|
input += AES_BLOCKLEN;
|
||||||
|
output += AES_BLOCKLEN;
|
||||||
}
|
}
|
||||||
|
|
||||||
// If iv is passed as 0, we continue to encrypt without re-setting the Iv
|
|
||||||
if (iv != 0)
|
|
||||||
{
|
|
||||||
Iv = (uint8_t*)iv;
|
|
||||||
}
|
|
||||||
|
|
||||||
for (i = 0; i < length; i += BLOCKLEN)
|
|
||||||
{
|
|
||||||
memcpy(output, input, BLOCKLEN);
|
|
||||||
state = (state_t*)output;
|
|
||||||
InvCipher();
|
|
||||||
XorWithIv(output);
|
|
||||||
Iv = input;
|
|
||||||
input += BLOCKLEN;
|
|
||||||
output += BLOCKLEN;
|
|
||||||
}
|
|
||||||
|
|
||||||
if (extra)
|
|
||||||
{
|
|
||||||
memcpy(output, input, extra);
|
|
||||||
state = (state_t*)output;
|
|
||||||
InvCipher();
|
|
||||||
}
|
|
||||||
}
|
}
|
||||||
|
|
||||||
#endif // #if defined(CBC) && (CBC == 1)
|
#endif // #if defined(CBC) && (CBC == 1)
|
||||||
@ -601,38 +558,34 @@ void AES_CBC_decrypt_buffer(uint8_t* output, uint8_t* input, uint32_t length, co
|
|||||||
#if defined(CTR) && (CTR == 1)
|
#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 */
|
/* 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(uint8_t* output, uint8_t* input, uint32_t length, const uint8_t* key, const uint8_t* nonce)
|
void AES_CTR_xcrypt_buffer(struct AES_ctx *ctx,uint8_t* output, uint8_t* input, uint32_t length)
|
||||||
{
|
{
|
||||||
uint8_t buffer[BLOCKLEN], counter[BLOCKLEN];
|
uint8_t buffer[AES_BLOCKLEN];
|
||||||
|
|
||||||
memcpy(counter, nonce, BLOCKLEN);
|
|
||||||
Key = key;
|
|
||||||
KeyExpansion();
|
|
||||||
|
|
||||||
int j;
|
int j;
|
||||||
unsigned i;
|
unsigned i;
|
||||||
for (i = 0; i < length; ++i)
|
for (i = 0; i < length; ++i)
|
||||||
{
|
{
|
||||||
if ((i & (BLOCKLEN - 1)) == 0)
|
if ((i & (AES_BLOCKLEN - 1)) == 0) //we need to regen xor compliment in buff
|
||||||
{
|
{
|
||||||
memcpy(buffer, counter, BLOCKLEN);
|
|
||||||
state = (state_t*)buffer;
|
memcpy(buffer, ctx->Iv, AES_BLOCKLEN);
|
||||||
Cipher();
|
Cipher((state_t*)buffer,ctx->RoundKey);
|
||||||
|
|
||||||
/* Increment counter and handle overflow */
|
/* Increment counter and handle overflow */
|
||||||
for (j = (BLOCKLEN - 1); j >= 0; --j)
|
for (j = (AES_BLOCKLEN - 1); j >= 0; --j)
|
||||||
{
|
{
|
||||||
counter[j] += 1;
|
ctx->Iv[j] += 1;
|
||||||
|
|
||||||
/* Break if no overflow, keep going otherwise */
|
/* Break if no overflow, keep going otherwise */
|
||||||
if (counter[j] != 0)
|
if (ctx->Iv[j] != 0)
|
||||||
{
|
{
|
||||||
break;
|
break;
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
output[i] = (input[i] ^ buffer[(i & (BLOCKLEN - 1))]);
|
output[i] = (input[i] ^ buffer[(i & (AES_BLOCKLEN - 1))]);
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
|
52
aes.h
52
aes.h
@ -28,26 +28,62 @@
|
|||||||
//#define AES192 1
|
//#define AES192 1
|
||||||
//#define AES256 1
|
//#define AES256 1
|
||||||
|
|
||||||
#if defined(ECB) && (ECB == 1)
|
#define AES_BLOCKLEN 16 //Block length in bytes AES is 128b block only
|
||||||
|
|
||||||
void AES_ECB_encrypt(const uint8_t* input, const uint8_t* key, uint8_t *output, const uint32_t length);
|
#if defined(AES256) && (AES256 == 1)
|
||||||
void AES_ECB_decrypt(const uint8_t* input, const uint8_t* key, uint8_t *output, const uint32_t length);
|
#define AES_KEYLEN 32
|
||||||
|
#define AES_keyExpSize 240
|
||||||
|
#elif defined(AES192) && (AES192 == 1)
|
||||||
|
#define AES_KEYLEN 24
|
||||||
|
#define AES_keyExpSize 208
|
||||||
|
#else
|
||||||
|
#define AES_KEYLEN 16 // Key length in bytes
|
||||||
|
#define AES_keyExpSize 176
|
||||||
|
#endif
|
||||||
|
|
||||||
|
struct AES_ctx {
|
||||||
|
uint8_t RoundKey[AES_keyExpSize];
|
||||||
|
#if (defined(CBC) && (CBC == 1)) || (defined(CTR) && (CTR == 1))
|
||||||
|
uint8_t Iv[AES_BLOCKLEN];
|
||||||
|
#endif
|
||||||
|
};
|
||||||
|
|
||||||
|
void AES_init_ctx(struct AES_ctx *ctx,const uint8_t* key);
|
||||||
|
#if defined(CBC) && (CBC == 1)
|
||||||
|
void AES_init_ctx_iv(struct AES_ctx *ctx,const uint8_t* key,const uint8_t* iv);
|
||||||
|
void AES_ctx_set_iv(struct AES_ctx *ctx,const uint8_t* iv);
|
||||||
|
#endif
|
||||||
|
|
||||||
|
#if defined(ECB) && (ECB == 1)
|
||||||
|
// buffer size is exactly AES_BLOCKLEN bytes;
|
||||||
|
// you need only AES_init_ctx as Iv is not used in ECB
|
||||||
|
// NB: ECB s considered insecure
|
||||||
|
void AES_ECB_encrypt(struct AES_ctx *ctx, const uint8_t* input, uint8_t *output);
|
||||||
|
void AES_ECB_decrypt(struct AES_ctx *ctx, const uint8_t* input, uint8_t *output);
|
||||||
|
|
||||||
#endif // #if defined(ECB) && (ECB == !)
|
#endif // #if defined(ECB) && (ECB == !)
|
||||||
|
|
||||||
|
|
||||||
#if defined(CBC) && (CBC == 1)
|
#if defined(CBC) && (CBC == 1)
|
||||||
|
// buffer size MUST be mutile of AES_BLOCKLEN;
|
||||||
void AES_CBC_encrypt_buffer(uint8_t* output, uint8_t* input, uint32_t length, const uint8_t* key, const uint8_t* iv);
|
// We suggest https://en.wikipedia.org/wiki/Padding_(cryptography)#PKCS7 if you need one
|
||||||
void AES_CBC_decrypt_buffer(uint8_t* output, uint8_t* input, uint32_t length, const uint8_t* key, const uint8_t* iv);
|
// you need to set iv in ctx via AES_init_ctx_iv or AES_ctx_set_iv
|
||||||
|
// NB: no IV should ever be reused with the same key
|
||||||
|
void AES_CBC_encrypt_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* output, uint8_t* input, uint32_t length);
|
||||||
|
|
||||||
#endif // #if defined(CBC) && (CBC == 1)
|
#endif // #if defined(CBC) && (CBC == 1)
|
||||||
|
|
||||||
|
|
||||||
#if defined(CTR) && (CTR == 1)
|
#if defined(CTR) && (CTR == 1)
|
||||||
|
|
||||||
/* Same function for encrypting as for decrypting. Note no IV/nonce should ever be reused with the same key */
|
// Same function for encrypting as for decrypting.
|
||||||
void AES_CTR_xcrypt_buffer(uint8_t* output, uint8_t* input, uint32_t length, const uint8_t* key, const uint8_t* nonce);
|
// iv is incremented for every block, and usesd after encryption as xor compliment for output
|
||||||
|
// buffer size MUST be mutile of AES_BLOCKLEN;
|
||||||
|
// We suggest https://en.wikipedia.org/wiki/Padding_(cryptography)#PKCS7 if you need one
|
||||||
|
// you need to set iv in ctx via AES_init_ctx_iv or AES_ctx_set_iv
|
||||||
|
// NB: no IV should ever be reused with the same key
|
||||||
|
void AES_CTR_xcrypt_buffer(struct AES_ctx *ctx, uint8_t* output, uint8_t* input, uint32_t length);
|
||||||
|
|
||||||
#endif // #if defined(CTR) && (CTR == 1)
|
#endif // #if defined(CTR) && (CTR == 1)
|
||||||
|
|
||||||
|
29
test.c
29
test.c
@ -97,9 +97,11 @@ static void test_encrypt_ecb_verbose(void)
|
|||||||
|
|
||||||
// print the resulting cipher as 4 x 16 byte strings
|
// print the resulting cipher as 4 x 16 byte strings
|
||||||
printf("ciphertext:\n");
|
printf("ciphertext:\n");
|
||||||
|
struct AES_ctx ctx;
|
||||||
|
AES_init_ctx(&ctx,key);
|
||||||
for(i = 0; i < 4; ++i)
|
for(i = 0; i < 4; ++i)
|
||||||
{
|
{
|
||||||
AES_ECB_encrypt(plain_text + (i*16), key, buf+(i*16), 16);
|
AES_ECB_encrypt(&ctx,plain_text + (i*16), buf+(i*16));
|
||||||
phex(buf + (i*16));
|
phex(buf + (i*16));
|
||||||
}
|
}
|
||||||
printf("\n");
|
printf("\n");
|
||||||
@ -124,7 +126,8 @@ static void test_encrypt_ecb(void)
|
|||||||
uint8_t in[] = {0x6b, 0xc1, 0xbe, 0xe2, 0x2e, 0x40, 0x9f, 0x96, 0xe9, 0x3d, 0x7e, 0x11, 0x73, 0x93, 0x17, 0x2a};
|
uint8_t in[] = {0x6b, 0xc1, 0xbe, 0xe2, 0x2e, 0x40, 0x9f, 0x96, 0xe9, 0x3d, 0x7e, 0x11, 0x73, 0x93, 0x17, 0x2a};
|
||||||
uint8_t buffer[16];
|
uint8_t buffer[16];
|
||||||
|
|
||||||
AES_ECB_encrypt(in, key, buffer, 16);
|
struct AES_ctx ctx; AES_init_ctx(&ctx,key);
|
||||||
|
AES_ECB_encrypt(&ctx,in, buffer);
|
||||||
|
|
||||||
printf("ECB encrypt: ");
|
printf("ECB encrypt: ");
|
||||||
|
|
||||||
@ -167,8 +170,9 @@ static void test_decrypt_cbc(void)
|
|||||||
0x30, 0xc8, 0x1c, 0x46, 0xa3, 0x5c, 0xe4, 0x11, 0xe5, 0xfb, 0xc1, 0x19, 0x1a, 0x0a, 0x52, 0xef,
|
0x30, 0xc8, 0x1c, 0x46, 0xa3, 0x5c, 0xe4, 0x11, 0xe5, 0xfb, 0xc1, 0x19, 0x1a, 0x0a, 0x52, 0xef,
|
||||||
0xf6, 0x9f, 0x24, 0x45, 0xdf, 0x4f, 0x9b, 0x17, 0xad, 0x2b, 0x41, 0x7b, 0xe6, 0x6c, 0x37, 0x10 };
|
0xf6, 0x9f, 0x24, 0x45, 0xdf, 0x4f, 0x9b, 0x17, 0xad, 0x2b, 0x41, 0x7b, 0xe6, 0x6c, 0x37, 0x10 };
|
||||||
uint8_t buffer[64];
|
uint8_t buffer[64];
|
||||||
|
struct AES_ctx ctx;
|
||||||
AES_CBC_decrypt_buffer(buffer, in, 64, key, iv);
|
AES_init_ctx_iv(&ctx,key,iv);
|
||||||
|
AES_CBC_decrypt_buffer(&ctx,buffer, in, 64);
|
||||||
|
|
||||||
printf("CBC decrypt: ");
|
printf("CBC decrypt: ");
|
||||||
|
|
||||||
@ -211,8 +215,9 @@ static void test_encrypt_cbc(void)
|
|||||||
0xf6, 0x9f, 0x24, 0x45, 0xdf, 0x4f, 0x9b, 0x17, 0xad, 0x2b, 0x41, 0x7b, 0xe6, 0x6c, 0x37, 0x10 };
|
0xf6, 0x9f, 0x24, 0x45, 0xdf, 0x4f, 0x9b, 0x17, 0xad, 0x2b, 0x41, 0x7b, 0xe6, 0x6c, 0x37, 0x10 };
|
||||||
|
|
||||||
uint8_t buffer[64];
|
uint8_t buffer[64];
|
||||||
|
struct AES_ctx ctx;
|
||||||
AES_CBC_encrypt_buffer(buffer, in, 64, key, iv);
|
AES_init_ctx_iv(&ctx,key,iv);
|
||||||
|
AES_CBC_encrypt_buffer(&ctx,buffer, in, 64);
|
||||||
|
|
||||||
printf("CBC encrypt: ");
|
printf("CBC encrypt: ");
|
||||||
|
|
||||||
@ -266,8 +271,11 @@ static void test_xcrypt_ctr(const char* xcrypt)
|
|||||||
0x30, 0xc8, 0x1c, 0x46, 0xa3, 0x5c, 0xe4, 0x11, 0xe5, 0xfb, 0xc1, 0x19, 0x1a, 0x0a, 0x52, 0xef,
|
0x30, 0xc8, 0x1c, 0x46, 0xa3, 0x5c, 0xe4, 0x11, 0xe5, 0xfb, 0xc1, 0x19, 0x1a, 0x0a, 0x52, 0xef,
|
||||||
0xf6, 0x9f, 0x24, 0x45, 0xdf, 0x4f, 0x9b, 0x17, 0xad, 0x2b, 0x41, 0x7b, 0xe6, 0x6c, 0x37, 0x10 };
|
0xf6, 0x9f, 0x24, 0x45, 0xdf, 0x4f, 0x9b, 0x17, 0xad, 0x2b, 0x41, 0x7b, 0xe6, 0x6c, 0x37, 0x10 };
|
||||||
uint8_t buffer[64];
|
uint8_t buffer[64];
|
||||||
|
|
||||||
AES_CTR_xcrypt_buffer(buffer, in, 64, key, iv);
|
struct AES_ctx ctx;
|
||||||
|
AES_init_ctx_iv(&ctx,key,iv);
|
||||||
|
|
||||||
|
AES_CTR_xcrypt_buffer(&ctx,buffer, in, 64);
|
||||||
|
|
||||||
printf("CTR %s: ", xcrypt);
|
printf("CTR %s: ", xcrypt);
|
||||||
|
|
||||||
@ -299,8 +307,9 @@ static void test_decrypt_ecb(void)
|
|||||||
|
|
||||||
uint8_t out[] = {0x6b, 0xc1, 0xbe, 0xe2, 0x2e, 0x40, 0x9f, 0x96, 0xe9, 0x3d, 0x7e, 0x11, 0x73, 0x93, 0x17, 0x2a};
|
uint8_t out[] = {0x6b, 0xc1, 0xbe, 0xe2, 0x2e, 0x40, 0x9f, 0x96, 0xe9, 0x3d, 0x7e, 0x11, 0x73, 0x93, 0x17, 0x2a};
|
||||||
uint8_t buffer[16];
|
uint8_t buffer[16];
|
||||||
|
struct AES_ctx ctx;
|
||||||
AES_ECB_decrypt(in, key, buffer, 16);
|
AES_init_ctx(&ctx,key);
|
||||||
|
AES_ECB_decrypt(&ctx,in, buffer);
|
||||||
|
|
||||||
printf("ECB decrypt: ");
|
printf("ECB decrypt: ");
|
||||||
|
|
||||||
|
Loading…
Reference in New Issue
Block a user