此代碼是從Github找到的,因爲要使用加密. 不是原創.
加了點自己的代碼. 比如原版只能是加密16個字節緩衝. 而實戰環境中肯定是一個buffer.
所以我對buffer做了拆分. 直接傳遞key就可以了.
解密代碼並沒有動,有興趣的字節改一改解密代碼.
直接使用的工具對比的.加密緩衝之後的結果與工具一致.
所以我認爲沒問題了.
加密代碼:
/*
******************************************************************
** Advanced Encryption Standard implementation in C. **
** By Niyaz PK **
** E-mail: [email protected] **
** Downloaded from Website: www.hoozi.com **
******************************************************************
This is the source code for encryption using the latest AES algorithm.
AES algorithm is also called Rijndael algorithm. AES algorithm is
recommended for non-classified by the National Institute of Standards
and Technology(NIST), USA. Now-a-days AES is being used for almost
all encryption applications all around the world.
THE MAIN FEATURE OF THIS AES ENCRYPTION PROGRAM IS NOT EFFICIENCY; IT
IS SIMPLICITY AND READABILITY. THIS SOURCE CODE IS PROVIDED FOR ALL
TO UNDERSTAND THE AES ALGORITHM.
Comments are provided as needed to understand the program. But the
user must read some AES documentation to understand the underlying
theory correctly.
It is not possible to describe the complete AES algorithm in detail
here. For the complete description of the algorithm, point your
browser to:
http://www.csrc.nist.gov/publications/fips/fips197/fips-197.pdf
Find the Wikipedia page of AES at:
http://en.wikipedia.org/wiki/Advanced_Encryption_Standard
******************************************************************
*/
// Include stdio.h for standard input/output.
// Used for giving output to the screen.
#include<stdio.h>
//#include <stdlib.h>
//#include <memory>
// The number of columns comprising a state in AES. This is a constant in AES. Value=4
#define Nb 4
// The number of rounds in AES Cipher. It is simply initiated to zero. The actual value is recieved in the program.
int Nr = 0;
// The number of 32 bit words in the key. It is simply initiated to zero. The actual value is recieved in the program.
int Nk = 0;
// in - it is the array that holds the plain text to be encrypted.
// out - it is the array that holds the key for encryption.
// state - the array that holds the intermediate results during encryption.
unsigned char in[16] = { 0 }, out[16] = { 0 }, state[4][4] = { 0 };
// The array that stores the round keys.
unsigned char RoundKey[240] = { 0 };
// The Key input to the AES Program
unsigned char Key[32] = { 0 };
int getSBoxValue(int num)
{
int sbox[256] = {
//0 1 2 3 4 5 6 7 8 9 A B C D E F
0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76, //0
0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0, //1
0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15, //2
0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75, //3
0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84, //4
0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf, //5
0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8, //6
0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2, //7
0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73, //8
0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb, //9
0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79, //A
0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08, //B
0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a, //C
0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e, //D
0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf, //E
0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16 }; //F
return sbox[num];
}
// The round constant word array, Rcon[i], contains the values given by
// x to th e power (i-1) being powers of x (x is denoted as {02}) in the field GF(28)
// Note that i starts at 1, not 0).
int Rcon[255] = {
0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a,
0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39,
0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a,
0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8,
0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef,
0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc,
0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b,
0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3,
0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94,
0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20,
0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35,
0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f,
0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04,
0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63,
0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd,
0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb };
// This function produces Nb(Nr+1) round keys. The round keys are used in each round to encrypt the states.
void KeyExpansion()
{
int i, j;
unsigned char temp[4], k;
// The first round key is the key itself.
for (i = 0; i < Nk; i++)
{
RoundKey[i * 4] = Key[i * 4];
RoundKey[i * 4 + 1] = Key[i * 4 + 1];
RoundKey[i * 4 + 2] = Key[i * 4 + 2];
RoundKey[i * 4 + 3] = Key[i * 4 + 3];
}
// All other round keys are found from the previous round keys.
while (i < (Nb * (Nr + 1)))
{
for (j = 0; j < 4; j++)
{
temp[j] = RoundKey[(i - 1) * 4 + j];
}
if (i % Nk == 0)
{
// This function rotates the 4 bytes in a word to the left once.
// [a0,a1,a2,a3] becomes [a1,a2,a3,a0]
// Function RotWord()
{
k = temp[0];
temp[0] = temp[1];
temp[1] = temp[2];
temp[2] = temp[3];
temp[3] = k;
}
// SubWord() is a function that takes a four-byte input word and
// applies the S-box to each of the four bytes to produce an output word.
// Function Subword()
{
temp[0] = getSBoxValue(temp[0]);
temp[1] = getSBoxValue(temp[1]);
temp[2] = getSBoxValue(temp[2]);
temp[3] = getSBoxValue(temp[3]);
}
temp[0] = temp[0] ^ Rcon[i / Nk];
}
else if (Nk > 6 && i % Nk == 4)
{
// Function Subword()
{
temp[0] = getSBoxValue(temp[0]);
temp[1] = getSBoxValue(temp[1]);
temp[2] = getSBoxValue(temp[2]);
temp[3] = getSBoxValue(temp[3]);
}
}
RoundKey[i * 4 + 0] = RoundKey[(i - Nk) * 4 + 0] ^ temp[0];
RoundKey[i * 4 + 1] = RoundKey[(i - Nk) * 4 + 1] ^ temp[1];
RoundKey[i * 4 + 2] = RoundKey[(i - Nk) * 4 + 2] ^ temp[2];
RoundKey[i * 4 + 3] = RoundKey[(i - Nk) * 4 + 3] ^ temp[3];
i++;
}
}
// This function adds the round key to state.
// The round key is added to the state by an XOR function.
void AddRoundKey(int round)
{
int i, j;
for (i = 0; i < 4; i++)
{
for (j = 0; j < 4; j++)
{
state[j][i] ^= RoundKey[round * Nb * 4 + i * Nb + j];
}
}
}
// The SubBytes Function Substitutes the values in the
// state matrix with values in an S-box.
void SubBytes()
{
int i, j;
for (i = 0; i < 4; i++)
{
for (j = 0; j < 4; j++)
{
state[i][j] = getSBoxValue(state[i][j]);
}
}
}
// The ShiftRows() function shifts the rows in the state to the left.
// Each row is shifted with different offset.
// Offset = Row number. So the first row is not shifted.
void ShiftRows()
{
unsigned char 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;
// Rotate second row 2 columns to left
temp = state[2][0];
state[2][0] = state[2][2];
state[2][2] = temp;
temp = state[2][1];
state[2][1] = state[2][3];
state[2][3] = 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;
}
// xtime is a macro that finds the product of {02} and the argument to xtime modulo {1b}
#define xtime(x) ((x<<1) ^ (((x>>7) & 1) * 0x1b))
// MixColumns function mixes the columns of the state matrix
void MixColumns()
{
int i;
unsigned char 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;
}
}
// Cipher is the main function that encrypts the PlainText.
void Cipher()
{
int i, j, 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];
}
}
// Add the First round key to the state before starting the rounds.
AddRoundKey(0);
// There will be Nr rounds.
// The first Nr-1 rounds are identical.
// These Nr-1 rounds are executed in the loop below.
for (round = 1; round < Nr; round++)
{
SubBytes();
ShiftRows();
MixColumns();
AddRoundKey(round);
}
// The last round is given below.
// The MixColumns function is not here in the last round.
SubBytes();
ShiftRows();
AddRoundKey(Nr);
// 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];
}
}
}
/*
加密函數一次只是加密16個緩衝數據
*/
char* encode_hexbuffer(unsigned char* _key, unsigned int _keysize, unsigned char* enBuffer, unsigned int enbuffersize)
{
unsigned char* OutBuffer = (unsigned char*)malloc(16);
//unsigned char* inBuffer = (unsigned char*)malloc(16);
memset(OutBuffer, 0, 16);
//memset(inBuffer, 0, 16);
Nr = 128;
Nk = Nr / 32;
Nr = Nk + 6;
//拷貝key
memcpy(Key, _key, _keysize);
//拷貝明文
memcpy(in, enBuffer, enbuffersize);
//unsigned char temp[16] = "abcdabcdabcdabcd"; //key使用的是相同的.但是隻能一次加密16個字節. 所以需要封裝成函數
//unsigned char temp2[16] = "HelloWorld";
//for (int i = 0; i < Nk * 4; i++)
//{
// Key[i] = temp[i];
// in[i] = temp2[i];
//}
// The KeyExpansion routine must be called before encryption.
KeyExpansion();
// The next function call encrypts the PlainText with the Key using AES algorithm.
Cipher();
// Output the encrypted text.
//printf("\nText after encryption:\n");
//for (int i = 0; i < Nk * 4; i++)
//{
// printf("%02x ", out[i]);
//}
//printf("\n\n");
memcpy(OutBuffer, out, 16);
return OutBuffer; //外面注意釋放內存
}
//封裝的加密函數.根據緩衝區拆分分段加密 返回加密的緩衝區
unsigned char* encode_buffer(
unsigned char* key, //要加密使用的Key
unsigned int _keysize, //要加密使用的Key長度
unsigned char* en_buffer, //要加密的緩衝區,內部使用0來填充需要滿足16個字節對齊
unsigned int enbuffer_size) //加密緩衝區的長度
{
/*
1.拆分用戶輸入,按照16個字節一組進行拆分並且進行加密.
2.累加加密的值
*/
unsigned int outBufferCurSize = 16;
unsigned char* OutBuffer = NULL;
unsigned int enBufferSize = enbuffer_size;
unsigned int count = enBufferSize / 16; //得出需要加密的次數. 然後剩餘的字節進行添零加密
unsigned int residue = enBufferSize % 16; //剩餘需要加密的次數
for (int i = 0; i < count; i++)
{
unsigned char* Inbuffer = malloc(16);
memset(Inbuffer, 0, 16);
memcpy(Inbuffer, (char*)en_buffer + (i * 16), 16); //從後往前進行加密
unsigned char* debuffer = encode_hexbuffer(key, 16, Inbuffer, 16);
//使用完注意釋放內存
if (Inbuffer != NULL)
{
free(Inbuffer);
Inbuffer = NULL;
}
if (OutBuffer == NULL)
{
OutBuffer = malloc(outBufferCurSize);
memcpy(OutBuffer, debuffer, 16);
if (debuffer != NULL)
{
free(debuffer);
debuffer = NULL;
}
}
else
{
unsigned char* tempBuffer = malloc(outBufferCurSize);
memset(tempBuffer, 0, outBufferCurSize);
memcpy(tempBuffer, OutBuffer, outBufferCurSize);
//重新申請空間來保存新的值
free(OutBuffer);
OutBuffer = NULL;
OutBuffer = malloc(outBufferCurSize + 16);
memset(OutBuffer, 0, outBufferCurSize + 16);
if (OutBuffer != NULL)
{
//恢復保存之前的值
memcpy(OutBuffer, tempBuffer, outBufferCurSize);
if (tempBuffer != NULL)
{
free(tempBuffer);
tempBuffer = NULL;
}
}
outBufferCurSize += 16;
memcpy(OutBuffer + i * 16, debuffer, 16);
if (debuffer != NULL)
{
free(debuffer);
debuffer = NULL;
}
}
}
//處理剩餘字符,加密剩餘字符串.注意要與16個字節對齊
unsigned char* residueBuffer = malloc(16);
memset(residueBuffer, 0, 16);
//拷貝剩餘字符過來.
memcpy(residueBuffer, en_buffer + count * 16, residue);
//繼續加密一次
unsigned char* debuffer = encode_hexbuffer(key, sizeof(key) / sizeof(key[0]), residueBuffer, 16);
if (residueBuffer != NULL)
{
free(residueBuffer);
residueBuffer = NULL;
}
unsigned char* tempBuffer = malloc(outBufferCurSize);
memset(tempBuffer, 0, outBufferCurSize);
memcpy(tempBuffer, OutBuffer, outBufferCurSize);
//重新申請空間來保存新的值
free(OutBuffer);
OutBuffer = NULL;
OutBuffer = malloc(outBufferCurSize + 16);
memset(OutBuffer, 0, outBufferCurSize + 16);
if (OutBuffer != NULL)
{
//恢復保存之前的值
memcpy(OutBuffer, tempBuffer, outBufferCurSize);
if (tempBuffer != NULL)
{
free(tempBuffer);
tempBuffer = NULL;
}
}
outBufferCurSize += 16;
memcpy(OutBuffer + count * 16, debuffer, 16);
if (debuffer != NULL)
{
free(debuffer);
debuffer = NULL;
}
return OutBuffer;
}
//繼續進行封裝,其中key就是固定的值.直接傳入buffer即可.
unsigned char* encode(unsigned char* enbuffer,unsigned int enbuffersize)
{
unsigned char key[16] = "abcdabcdabcdabcd";
return encode_buffer(key, sizeof(key) / sizeof(key[0]), enbuffer, enbuffersize);
}
void main1()
{
int i;
// Recieve the length of key here.
//while(Nr!=128 && Nr!=192 && Nr!=256)
//{
// printf("Enter the length of Key(128, 192 or 256 only): ");
// scanf("%d",&Nr);
//}
Nr = 128;
// Calculate Nk and Nr from the recieved value.
Nk = Nr / 32;
Nr = Nk + 6;
// Part 1 is for demonstrative purpose. The key and plaintext are given in the program itself.
// Part 1: ********************************************************
// The array temp stores the key.
// The array temp2 stores the plaintext.
unsigned char temp[16] = "abcdabcdabcdabcd"; //key使用的是相同的.但是隻能一次加密16個字節. 所以需要封裝成函數
unsigned char temp2[16] = "HelloWorld";
// Copy the Key and PlainText
for (i = 0; i < Nk * 4; i++)
{
Key[i] = temp[i];
in[i] = temp2[i];
}
// *********************************************************
// Uncomment Part 2 if you need to read key and plaintext from the keyboard.
// Part 2: ********************************************************
/*
//Clear the input buffer
flushall();
//Recieve the key from the user
printf("Enter the Key in hexadecimal: ");
for(i=0;i<Nk*4;i++)
{
scanf("%x",&Key[i]);
}
printf("Enter the PlainText in hexadecimal: ");
for(i=0;i<Nb*4;i++)
{
scanf("%x",&in[i]);
}
*/
// ********************************************************
// The KeyExpansion routine must be called before encryption.
KeyExpansion();
// The next function call encrypts the PlainText with the Key using AES algorithm.
Cipher();
// Output the encrypted text.
printf("\nText after encryption:\n");
for (i = 0; i < Nk * 4; i++)
{
printf("%02x ", out[i]);
}
printf("\n\n");
}
int main2() {
//unsigned char key[16] = "abcdabcdabcdabcd";
//unsigned char plant[] = "qwertyuiop[]asdfghjkl;'zxcvbnm,./";
///*
//1.拆分用戶輸入,按照16個字節一組進行拆分並且進行加密.
//2.累加加密的值
//*/
//unsigned int outBufferCurSize = 16;
//unsigned char* OutBuffer = NULL;
////key使用的是相同的.但是隻能一次加密16個字節. 所以需要封裝成函數
//unsigned char key[16] = "abcdabcdabcdabcd";
//unsigned char plant[] = "qwertyuiop[]asdfghjkl;'zxcvbnm,./";
//unsigned int enBufferSize = sizeof(plant) / sizeof(plant[0]);
//unsigned int count = enBufferSize / 16; //得出需要加密的次數. 然後剩餘的字節進行添零加密
//unsigned int residue = enBufferSize % 16; //剩餘需要加密的次數
//for (int i = 0; i < count; i++)
//{
// unsigned char* Inbuffer = malloc(16);
// memset(Inbuffer, 0, 16);
// memcpy(Inbuffer, (char*)plant + (i * 16), 16); //從後往前進行加密
// unsigned char* debuffer = encode_hexbuffer(key, 16, Inbuffer, 16);
// if (OutBuffer == NULL)
// {
// OutBuffer = malloc(outBufferCurSize);
// memcpy(OutBuffer, debuffer, 16);
// if (debuffer != NULL)
// {
// free(debuffer);
// debuffer = NULL;
// }
// }
// else
// {
// unsigned char* tempBuffer = malloc(outBufferCurSize);
// memset(tempBuffer, 0, outBufferCurSize);
// memcpy(tempBuffer, OutBuffer, outBufferCurSize);
// //重新申請空間來保存新的值
// free(OutBuffer);
// OutBuffer = NULL;
// OutBuffer = malloc(outBufferCurSize + 16);
// memset(OutBuffer, 0, outBufferCurSize + 16);
// if (OutBuffer != NULL)
// {
// //恢復保存之前的值
// memcpy(OutBuffer, tempBuffer, outBufferCurSize);
// if (tempBuffer != NULL)
// {
// free(tempBuffer);
// tempBuffer = NULL;
// }
// }
// outBufferCurSize += 16;
// memcpy(OutBuffer + i * 16, debuffer, 16);
// if (debuffer != NULL)
// {
// free(debuffer);
// debuffer = NULL;
// }
// }
//}
////處理剩餘字符,加密剩餘字符串.注意要與16個字節對齊
//unsigned char* residueBuffer = malloc(16);
//memset(residueBuffer, 0, 16);
////拷貝剩餘字符過來.
//memcpy(residueBuffer, plant + count * 16, residue);
////繼續加密一次
//unsigned char* debuffer = encode_hexbuffer(key, sizeof(key) / sizeof(key[0]), residueBuffer, 16);
//if (residueBuffer != NULL)
//{
// free(residueBuffer);
// residueBuffer = NULL;
//}
//unsigned char* tempBuffer = malloc(outBufferCurSize);
//memset(tempBuffer, 0, outBufferCurSize);
//memcpy(tempBuffer, OutBuffer, outBufferCurSize);
////重新申請空間來保存新的值
//free(OutBuffer);
//OutBuffer = NULL;
//OutBuffer = malloc(outBufferCurSize + 16);
//memset(OutBuffer, 0, outBufferCurSize + 16);
//if (OutBuffer != NULL)
//{
// //恢復保存之前的值
// memcpy(OutBuffer, tempBuffer, outBufferCurSize);
// if (tempBuffer != NULL)
// {
// free(tempBuffer);
// tempBuffer = NULL;
// }
//}
//outBufferCurSize += 16;
//memcpy(OutBuffer + count * 16, debuffer, 16);
//if (debuffer != NULL)
//{
// free(debuffer);
// debuffer = NULL;
//}
}
int main()
{
unsigned char plant[] = "poiuytrewqasdfghjkl/.,mnbvcxz15879884151sdfsqweqjomslfjsf&*8yfsd8f";
unsigned char* DeBuffer = encode(plant,sizeof(plant)/sizeof(plant[0]));
int a = 10;
}
解密代碼:
/*
******************************************************************
** Advanced Encryption Standard implementation in C. **
** By Niyaz PK **
** E-mail: [email protected] **
** Downloaded from Website: www.hoozi.com **
******************************************************************
This is the source code for decryption using the latest AES algorithm.
AES algorithm is also called Rijndael algorithm. AES algorithm is
recommended for non-classified use by the National Institute of Standards
and Technology(NIST), USA. Now-a-days AES is being used for almost
all encryption applications all around the world.
THE MAIN FEATURE OF THIS AES ENCRYPTION PROGRAM IS NOT EFFICIENCY; IT
IS SIMPLICITY AND READABILITY. THIS SOURCE CODE IS PROVIDED FOR ALL
TO UNDERSTAND THE AES ALGORITHM.
Comments are provided as needed to understand the program. But the
user must read some AES documentation to understand the underlying
theory correctly.
It is not possible to describe the complete AES algorithm in detail
here. For the complete description of the algorithm, point your
browser to:
http://www.csrc.nist.gov/publications/fips/fips197/fips-197.pdf
Find the Wikipedia page of AES at:
http://en.wikipedia.org/wiki/Advanced_Encryption_Standard
******************************************************************
*/
// Include stdio.h for standard input/output.
// Used for giving output to the screen.
#include<stdio.h>
// The number of columns comprising a state in AES. This is a constant in AES. Value=4
#define Nb 4
// The number of rounds in AES Cipher. It is simply initiated to zero. The actual value is recieved in the program.
int Nr=0;
// The number of 32 bit words in the key. It is simply initiated to zero. The actual value is recieved in the program.
int Nk=0;
// in - it is the array that holds the CipherText to be decrypted.
// out - it is the array that holds the output of the for decryption.
// state - the array that holds the intermediate results during decryption.
unsigned char in[16], out[16], state[4][4];
// The array that stores the round keys.
unsigned char RoundKey[240];
// The Key input to the AES Program
unsigned char Key[32];
int getSBoxInvert(int num)
{
int rsbox[256] =
{ 0x52, 0x09, 0x6a, 0xd5, 0x30, 0x36, 0xa5, 0x38, 0xbf, 0x40, 0xa3, 0x9e, 0x81, 0xf3, 0xd7, 0xfb
, 0x7c, 0xe3, 0x39, 0x82, 0x9b, 0x2f, 0xff, 0x87, 0x34, 0x8e, 0x43, 0x44, 0xc4, 0xde, 0xe9, 0xcb
, 0x54, 0x7b, 0x94, 0x32, 0xa6, 0xc2, 0x23, 0x3d, 0xee, 0x4c, 0x95, 0x0b, 0x42, 0xfa, 0xc3, 0x4e
, 0x08, 0x2e, 0xa1, 0x66, 0x28, 0xd9, 0x24, 0xb2, 0x76, 0x5b, 0xa2, 0x49, 0x6d, 0x8b, 0xd1, 0x25
, 0x72, 0xf8, 0xf6, 0x64, 0x86, 0x68, 0x98, 0x16, 0xd4, 0xa4, 0x5c, 0xcc, 0x5d, 0x65, 0xb6, 0x92
, 0x6c, 0x70, 0x48, 0x50, 0xfd, 0xed, 0xb9, 0xda, 0x5e, 0x15, 0x46, 0x57, 0xa7, 0x8d, 0x9d, 0x84
, 0x90, 0xd8, 0xab, 0x00, 0x8c, 0xbc, 0xd3, 0x0a, 0xf7, 0xe4, 0x58, 0x05, 0xb8, 0xb3, 0x45, 0x06
, 0xd0, 0x2c, 0x1e, 0x8f, 0xca, 0x3f, 0x0f, 0x02, 0xc1, 0xaf, 0xbd, 0x03, 0x01, 0x13, 0x8a, 0x6b
, 0x3a, 0x91, 0x11, 0x41, 0x4f, 0x67, 0xdc, 0xea, 0x97, 0xf2, 0xcf, 0xce, 0xf0, 0xb4, 0xe6, 0x73
, 0x96, 0xac, 0x74, 0x22, 0xe7, 0xad, 0x35, 0x85, 0xe2, 0xf9, 0x37, 0xe8, 0x1c, 0x75, 0xdf, 0x6e
, 0x47, 0xf1, 0x1a, 0x71, 0x1d, 0x29, 0xc5, 0x89, 0x6f, 0xb7, 0x62, 0x0e, 0xaa, 0x18, 0xbe, 0x1b
, 0xfc, 0x56, 0x3e, 0x4b, 0xc6, 0xd2, 0x79, 0x20, 0x9a, 0xdb, 0xc0, 0xfe, 0x78, 0xcd, 0x5a, 0xf4
, 0x1f, 0xdd, 0xa8, 0x33, 0x88, 0x07, 0xc7, 0x31, 0xb1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xec, 0x5f
, 0x60, 0x51, 0x7f, 0xa9, 0x19, 0xb5, 0x4a, 0x0d, 0x2d, 0xe5, 0x7a, 0x9f, 0x93, 0xc9, 0x9c, 0xef
, 0xa0, 0xe0, 0x3b, 0x4d, 0xae, 0x2a, 0xf5, 0xb0, 0xc8, 0xeb, 0xbb, 0x3c, 0x83, 0x53, 0x99, 0x61
, 0x17, 0x2b, 0x04, 0x7e, 0xba, 0x77, 0xd6, 0x26, 0xe1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0c, 0x7d };
return rsbox[num];
}
int getSBoxValue(int num)
{
int sbox[256] = {
//0 1 2 3 4 5 6 7 8 9 A B C D E F
0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76,
0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0,
0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15,
0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75,
0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84,
0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf,
0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8,
0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2,
0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73,
0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb,
0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79,
0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08,
0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a,
0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e,
0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf,
0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16 };
return sbox[num];
}
// The round constant word array, Rcon[i], contains the values given by
// x to th e power (i-1) being powers of x (x is denoted as {02}) in the field GF(2^8)
// Note that i starts at 1, not 0).
int Rcon[255] = {
0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a,
0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39,
0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a,
0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8,
0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef,
0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc,
0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b,
0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3,
0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94,
0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20,
0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35,
0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f,
0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04,
0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63,
0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd,
0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb };
// This function produces Nb(Nr+1) round keys. The round keys are used in each round to decrypt the states.
void KeyExpansion()
{
int i,j;
unsigned char temp[4],k;
// The first round key is the key itself.
for(i=0;i<Nk;i++)
{
RoundKey[i*4]=Key[i*4];
RoundKey[i*4+1]=Key[i*4+1];
RoundKey[i*4+2]=Key[i*4+2];
RoundKey[i*4+3]=Key[i*4+3];
}
// All other round keys are found from the previous round keys.
while (i < (Nb * (Nr+1)))
{
for(j=0;j<4;j++)
{
temp[j]=RoundKey[(i-1) * 4 + j];
}
if (i % Nk == 0)
{
// This function rotates the 4 bytes in a word to the left once.
// [a0,a1,a2,a3] becomes [a1,a2,a3,a0]
// Function RotWord()
{
k = temp[0];
temp[0] = temp[1];
temp[1] = temp[2];
temp[2] = temp[3];
temp[3] = k;
}
// SubWord() is a function that takes a four-byte input word and
// applies the S-box to each of the four bytes to produce an output word.
// Function Subword()
{
temp[0]=getSBoxValue(temp[0]);
temp[1]=getSBoxValue(temp[1]);
temp[2]=getSBoxValue(temp[2]);
temp[3]=getSBoxValue(temp[3]);
}
temp[0] = temp[0] ^ Rcon[i/Nk];
}
else if (Nk > 6 && i % Nk == 4)
{
// Function Subword()
{
temp[0]=getSBoxValue(temp[0]);
temp[1]=getSBoxValue(temp[1]);
temp[2]=getSBoxValue(temp[2]);
temp[3]=getSBoxValue(temp[3]);
}
}
RoundKey[i*4+0] = RoundKey[(i-Nk)*4+0] ^ temp[0];
RoundKey[i*4+1] = RoundKey[(i-Nk)*4+1] ^ temp[1];
RoundKey[i*4+2] = RoundKey[(i-Nk)*4+2] ^ temp[2];
RoundKey[i*4+3] = RoundKey[(i-Nk)*4+3] ^ temp[3];
i++;
}
}
// This function adds the round key to state.
// The round key is added to the state by an XOR function.
void AddRoundKey(int round)
{
int i,j;
for(i=0;i<4;i++)
{
for(j=0;j<4;j++)
{
state[j][i] ^= RoundKey[round * Nb * 4 + i * Nb + j];
}
}
}
// The SubBytes Function Substitutes the values in the
// state matrix with values in an S-box.
void InvSubBytes()
{
int i,j;
for(i=0;i<4;i++)
{
for(j=0;j<4;j++)
{
state[i][j] = getSBoxInvert(state[i][j]);
}
}
}
// The ShiftRows() function shifts the rows in the state to the left.
// Each row is shifted with different offset.
// Offset = Row number. So the first row is not shifted.
void InvShiftRows()
{
unsigned char 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;
// Rotate second row 2 columns to right
temp=state[2][0];
state[2][0]=state[2][2];
state[2][2]=temp;
temp=state[2][1];
state[2][1]=state[2][3];
state[2][3]=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;
}
// xtime is a macro that finds the product of {02} and the argument to xtime modulo {1b}
#define xtime(x) ((x<<1) ^ (((x>>7) & 1) * 0x1b))
// Multiplty is a macro used to multiply numbers in the field GF(2^8)
#define Multiply(x,y) (((y & 1) * x) ^ ((y>>1 & 1) * xtime(x)) ^ ((y>>2 & 1) * xtime(xtime(x))) ^ ((y>>3 & 1) * xtime(xtime(xtime(x)))) ^ ((y>>4 & 1) * xtime(xtime(xtime(xtime(x))))))
// MixColumns function mixes the columns of the state matrix.
// The method used to multiply may be difficult to understand for the inexperienced.
// Please use the references to gain more information.
void InvMixColumns()
{
int i;
unsigned char a,b,c,d;
for(i=0;i<4;i++)
{
a = state[0][i];
b = state[1][i];
c = state[2][i];
d = state[3][i];
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);
}
}
// InvCipher is the main function that decrypts the CipherText.
void InvCipher()
{
int i,j,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];
}
}
// Add the First round key to the state before starting the rounds.
AddRoundKey(Nr);
// There will be Nr rounds.
// The first Nr-1 rounds are identical.
// These Nr-1 rounds are executed in the loop below.
for(round=Nr-1;round>0;round--)
{
InvShiftRows();
InvSubBytes();
AddRoundKey(round);
InvMixColumns();
}
// The last round is given below.
// The MixColumns function is not here in the last round.
InvShiftRows();
InvSubBytes();
AddRoundKey(0);
// 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];
}
}
}
void main()
{
int i;
// Recieve the length of key here.
while(Nr!=128 && Nr!=192 && Nr!=256)
{
printf("Enter the length of Key(128, 192 or 256 only): ");
scanf("%d",&Nr);
}
// Calculate Nk and Nr from the recieved value.
Nk = Nr / 32;
Nr = Nk + 6;
// Part 1 is for demonstrative purpose. The key and plaintext are given in the program itself.
// Part 1: ********************************************************
// The array temp stores the key.
// The array temp2 stores the plaintext.
unsigned char temp[32] = {0x00 ,0x01 ,0x02 ,0x03 ,0x04 ,0x05 ,0x06 ,0x07 ,0x08 ,0x09 ,0x0a ,0x0b ,0x0c ,0x0d ,0x0e ,0x0f};
unsigned char temp2[16]= {0x69 ,0xc4 ,0xe0 ,0xd8 ,0x6a ,0x7b ,0x04 ,0x30 ,0xd8 ,0xcd ,0xb7 ,0x80 ,0x70 ,0xb4 ,0xc5 ,0x5a};
// Copy the Key and CipherText
for(i=0;i<Nk*4;i++)
{
Key[i]=temp[i];
in[i]=temp2[i];
}
// *********************************************************
// Uncomment Part 2 if you need to read Key and CipherText from the keyboard.
// Part 2: ********************************************************
/*
//Clear the input buffer
flushall();
//Recieve the Key from the user
printf("Enter the Key in hexadecimal: ");
for(i=0;i<Nk*4;i++)
{
scanf("%x",&Key[i]);
}
printf("Enter the CipherText in hexadecimal: ");
for(i=0;i<Nb*4;i++)
{
scanf("%x",&in[i]);
}
*/
// ********************************************************
//The Key-Expansion routine must be called before the decryption routine.
KeyExpansion();
// The next function call decrypts the CipherText with the Key using AES algorithm.
InvCipher();
// Output the decrypted text.
printf("\nText after decryption:\n");
for(i=0;i<Nb*4;i++)
{
printf("%02x ",out[i]);
}
printf("\n\n");
}