AES算法加密C语言完整程序

#include "aes.h"

#include "commonage.h"

#define byte unsigned char

#define BPOLY 0x1b //!< Lower 8 bits of (x^8+x^4+x^3+x+1), ie. (x^4+x^3+x+1).

#define BLOCKSIZE 16 //!< Block size in number of bytes.

#define KEYBITS 128 //!< Use AES128.

#define ROUNDS 10 //!< Number of rounds.

#define KEYLENGTH 16 //!< Key length in number of bytes.

byte xdata block1[ 256 ]; //!< Workspace 1.

byte xdata block2[ 256 ]; //!< Worksapce 2.

byte xdata * powTbl; //!< Final location of exponentiation lookup table.

byte xdata * logTbl; //!< Final location of logarithm lookup table.

byte xdata * sBox; //!< Final location of s-box.

byte xdata * sBoxInv; //!< Final location of inverse s-box.

byte xdata * expandedKey; //!< Final location of expanded key.

void CalcPowLog( byte * powTbl, byte * logTbl )

{

byte xdata i = 0;

byte xdata t = 1;

do {

// Use 0x03 as root for exponentiation and logarithms.

powTbl[i] = t;

logTbl[t] = i;

i++;

// Muliply t by 3 in GF(2^8).

t ^= (t << 1) ^ (t & 0x80 ? BPOLY : 0);

} while( t != 1 ); // Cyclic properties ensure that i < 255.

powTbl[255] = powTbl[0]; // 255 = '-0', 254 = -1, etc.

}

void CalcSBox( byte * sBox )

{

byte xdata i, rot;

byte xdata temp;

byte xdata result;

// Fill all entries of sBox[].

i = 0;

do {

// Inverse in GF(2^8).

if( i > 0 ) {

temp = powTbl[ 255 - logTbl[i] ];

} else {

temp = 0;

}

// Affine transformation in GF(2).

result = temp ^ 0x63; // Start with adding a vector in GF(2).

for( rot = 0; rot < 4; rot++ ) {

// Rotate left.

temp = (temp<<1) | (temp>>7);

// Add rotated byte in GF(2).

result ^= temp;

}

// Put result in table.

sBox[i] = result;

} while( ++i != 0 );

}

void CalcSBoxInv( byte * sBox, byte * sBoxInv )

{

byte xdata i = 0;

byte xdata j = 0;

// Iterate through all elements in sBoxInv using i.

do {

// Search through sBox using j.

cleardog();

do {

// Check if current j is the inverse of current i.

if( sBox[ j ] == i ) {

// If so, set sBoxInc and indicate search finished.

sBoxInv[ i ] = j;

j = 255;

}

} while( ++j != 0 );

} while( ++i != 0 );

}

void CycleLeft( byte * row )

{

// Cycle 4 bytes in an array left once.

byte xdata temp = row[0];

row[0] = row[1];

row[1] = row[2];

row[2] = row[3];

row[3] = temp;

}

void InvMixColumn( byte * column )

{

byte xdata r0, r1, r2, r3;

r0 = column[1] ^ column[2] ^ column[3];

r1 = column[0] ^ column[2] ^ column[3];

r2 = column[0] ^ column[1] ^ column[3];

r3 = column[0] ^ column[1] ^ column[2];

column[0] = (column[0] << 1) ^ (column[0] & 0x80 ? BPOLY : 0);

column

[1] = (column[1] << 1) ^ (column[1] & 0x80 ? BPOLY : 0);

column[2] = (column[2] << 1) ^ (column[2] & 0x80 ? BPOLY : 0);

column[3] = (column[3] << 1) ^ (column[3] & 0x80 ? BPOLY : 0);

r0 ^= column[0] ^ column[1];

r1 ^= column[1] ^ column[2];

r2 ^= column[2] ^ column[3];

r3 ^= column[0] ^ column[3];

column[0] = (column[0] << 1) ^ (column[0] & 0x80 ? BPOLY : 0);

column[1] = (column[1] << 1) ^ (column[1] & 0x80 ? BPOLY : 0);

column[2] = (column[2] << 1) ^ (column[2] & 0x80 ? BPOLY : 0);

column[3] = (column[3] << 1) ^ (column[3] & 0x80 ? BPOLY : 0);

r0 ^= column[0] ^ column[2];

r1 ^= column[1] ^ column[3];

r2 ^= column[0] ^ column[2];

r3 ^= column[1] ^ column[3];

column[0] = (column[0] << 1) ^ (column[0] & 0x80 ? BPOLY : 0);

column[1] = (column[1] << 1) ^ (column[1] & 0x80 ? BPOLY : 0);

column[2] = (column[2] << 1) ^ (column[2] & 0x80 ? BPOLY : 0);

column[3] = (column[3] << 1) ^ (column[3] & 0x80 ? BPOLY : 0);

column[0] ^= column[1] ^ column[2] ^ column[3];

r0 ^= column[0];

r1 ^= column[0];

r2 ^= column[0];

r3 ^= column[0];

column[0] = r0;

column[1] = r1;

column[2] = r2;

column[3] = r3;

}

byte Multiply( unsigned char num, unsigned char factor )

{

byte mask = 1;

byte result = 0;

while( mask != 0 ) {

// Check bit of factor given by mask.

if( mask & factor ) {

// Add current multiple of num in GF(2).

result ^= num;

}

// Shift mask to indicate next bit.

mask <<= 1;

// Double num.

num = (num << 1) ^ (num & 0x80 ? BPOLY : 0);

}

return result;

}

byte DotProduct( unsigned char * vector1, unsigned char * vector2 )

{

byte result = 0;

result ^= Multiply( *vector1++, *vector2++ );

result ^= Multiply( *vector1++, *vector2++ );

result ^= Multiply( *vector1++, *vector2++ );

result ^= Multiply( *vector1 , *vector2 );

return result;

}

void MixColumn( byte * column )

{

byte xdata row[8] = {

0x02, 0x03, 0x01, 0x01,

0x02, 0x03, 0x01, 0x01

}; // Prepare first row of matrix twice, to eliminate need for cycling.

byte xdata result[4];

// Take dot products of each matrix row and the column vector.

result[0] = DotProduct( row+0, column );

result[1] = DotProduct( row+3, column );

result[2] = DotProduct( row+2, column );

result[3] = DotProduct( row+1, column );

// Copy temporary result to original column.

column[0] = result[0];

column[1] = result[1];

column[2] = result[2];

column[3] = result[3];

}

void SubBytes( byte * bytes, byte count )

{

do {

*bytes = sBox[ *bytes ]; // Substitute every byte in state.

bytes++;

} while( --count );

}

void InvSubBytesAndXOR( byte * bytes, byte * key, byte count )

{

do {

// *bytes = sBoxInv[ *bytes ] ^ *key; // Inverse substitute every byte in state and add key.

*bytes = block2[ *bytes ] ^ *key; // Use block2 directly. Increases speed.

bytes++;

key++;

} while( --count );

}

void

InvShiftRows( byte * state )

{

byte temp;

// Note: State is arranged column by column.

// Cycle second row right one time.

temp = state[ 1 + 3*4 ];

state[ 1 + 3*4 ] = state[ 1 + 2*4 ];

state[ 1 + 2*4 ] = state[ 1 + 1*4 ];

state[ 1 + 1*4 ] = state[ 1 + 0*4 ];

state[ 1 + 0*4 ] = temp;

// Cycle third row right two times.

temp = state[ 2 + 0*4 ];

state[ 2 + 0*4 ] = state[ 2 + 2*4 ];

state[ 2 + 2*4 ] = temp;

temp = state[ 2 + 1*4 ];

state[ 2 + 1*4 ] = state[ 2 + 3*4 ];

state[ 2 + 3*4 ] = temp;

// Cycle fourth row right three times, ie. left once.

temp = state[ 3 + 0*4 ];

state[ 3 + 0*4 ] = state[ 3 + 1*4 ];

state[ 3 + 1*4 ] = state[ 3 + 2*4 ];

state[ 3 + 2*4 ] = state[ 3 + 3*4 ];

state[ 3 + 3*4 ] = temp;

}

void ShiftRows( byte * state )

{

byte temp;

// Note: State is arranged column by column.

// Cycle second row left one time.

temp = state[ 1 + 0*4 ];

state[ 1 + 0*4 ] = state[ 1 + 1*4 ];

state[ 1 + 1*4 ] = state[ 1 + 2*4 ];

state[ 1 + 2*4 ] = state[ 1 + 3*4 ];

state[ 1 + 3*4 ] = temp;

// Cycle third row left two times.

temp = state[ 2 + 0*4 ];

state[ 2 + 0*4 ] = state[ 2 + 2*4 ];

state[ 2 + 2*4 ] = temp;

temp = state[ 2 + 1*4 ];

state[ 2 + 1*4 ] = state[ 2 + 3*4 ];

state[ 2 + 3*4 ] = temp;

// Cycle fourth row left three times, ie. right once.

temp = state[ 3 + 3*4 ];

state[ 3 + 3*4 ] = state[ 3 + 2*4 ];

state[ 3 + 2*4 ] = state[ 3 + 1*4 ];

state[ 3 + 1*4 ] = state[ 3 + 0*4 ];

state[ 3 + 0*4 ] = temp;

}

void InvMixColumns( byte * state )

{

InvMixColumn( state + 0*4 );

InvMixColumn( state + 1*4 );

InvMixColumn( state + 2*4 );

InvMixColumn( state + 3*4 );

}

void MixColumns( byte * state )

{

MixColumn( state + 0*4 );

MixColumn( state + 1*4 );

MixColumn( state + 2*4 );

MixColumn( state + 3*4 );

}

void XORBytes( byte * bytes1, byte * bytes2, byte count )

{

do {

*bytes1 ^= *bytes2; // Add in GF(2), ie. XOR.

bytes1++;

bytes2++;

} while( --count );

}

void CopyBytes( byte * to, byte * from, byte count )

{

do {

*to = *from;

to++;

from++;

} while( --count );

}

void KeyExpansion( byte * expandedKey )

{

byte xdata temp[4];

byte i;

byte xdata Rcon[4] = { 0x01, 0x00, 0x00, 0x00 }; // Round constant.

unsigned char xdata *key;

unsigned char xdata a[16];

key=a;

//以下为加解密密码，共16字节。可以选择任意值

key[0]=0x30;

key[1]=0x30;

key[2]=0x30;

key[3]=0x30;

key[4]=0x30;

key[5]=0x30;

key[6]=0x30;

key[7]=0x30;

key[8]=0x30;

key[9]=0x30;

key[10]=0x30;

key[11]=0x30;

key[12]=0x30;

key[13]=0x30;

key[14]=0x30;

key[15]=0x30;

////////////////////////////////////////////

// Copy key to start of expanded key.

i = KEYLENGTH;

do {

*expandedKey = *key;

expandedKey++;

key++;

} while( --i );

// Prepare last 4 bytes of key in temp.

expandedKey -= 4;

temp[0] = *(expandedKey++);

temp[1] = *(expandedKey++);

temp[2] = *(expandedKey++);

temp[3] = *(expandedKey++);

// Expand key.

i = KEYLENGTH;

while( i < BLOCKSIZE*(ROUNDS+1) ) {

// Are we at the start of a multiple of the key size?

if( (i % KEYLENGTH) == 0 ) {

CycleLeft( temp ); // Cycle left once.

SubBytes( temp, 4 ); // Substitute each byte.

XORBytes( temp, Rcon, 4 ); // Add constant in GF(2).

*Rcon = (*Rcon << 1) ^ (*Rcon & 0x80 ? BPOLY : 0);

}

// Keysize larger than 24 bytes, ie. larger that 192 bits?

#if KEYLENGTH > 24

// Are we right past a block size?

else if( (i % KEYLENGTH) == BLOCKSIZE ) {

SubBytes( temp, 4 ); // Substitute each byte.

}

#endif

// Add bytes in GF(2) one KEYLENGTH away.

XORBytes( temp, expandedKey - KEYLENGTH, 4 );

// Copy result to current 4 bytes.

*(expandedKey++) = temp[ 0 ];

*(expandedKey++) = temp[ 1 ];

*(expandedKey++) = temp[ 2 ];

*(expandedKey++) = temp[ 3 ];

i += 4; // Next 4 bytes.

}

}

void InvCipher( byte * block, byte * expandedKey )

{

byte round = ROUNDS-1;

expandedKey += BLOCKSIZE * ROUNDS;

XORBytes( block, expandedKey, 16 );

expandedKey -= BLOCKSIZE;

do {

InvShiftRows( block );

InvSubBytesAndXOR( block, expandedKey, 16 );

expandedKey -= BLOCKSIZE;

InvMixColumns( block );

} while( --round );

InvShiftRows( block );

InvSubBytesAndXOR( block, expandedKey, 16 );

}

void Cipher( byte * block, byte * expandedKey ) //完成一个块(16字节，128bit)的加密

{

byte round = ROUNDS-1;

XORBytes( block, expandedKey, 16 );

expandedKey += BLOCKSIZE;

do {

SubBytes( block, 16 );

ShiftRows( block );

MixColumns( block );

XORBytes( block, expandedKey, 16 );

expandedKey += BLOCKSIZE;

} while( --round );

SubBytes( block, 16 );

ShiftRows( block );

XORBytes( block, expandedKey, 16 );

}

void aesInit( unsigned char * tempbuf )

{

powTbl = block1;

logTbl = block2;

CalcPowLog( powTbl, logTbl );

sBox = tempbuf;

CalcSBox( sBox );

expandedKey = block1; //至此block1用来存贮密码表

KeyExpansion( expandedKey );

sBoxInv = block2; // Must be block2. block2至此开始只用来存贮SBOXINV

CalcSBoxInv( sBox, sBoxInv );

}

//对一个16字节块解密,参数buffer是解密密缓存，chainBlock是要解密的块

void aesDecrypt( unsigned char * buffer, unsigned char * chainBlock )

{

//byte xdata temp[ BLOCKSIZE ];

//CopyBytes( temp, buffer, BLOCKSIZE );

CopyBytes(buffer,chainBlock,BLOCKSIZE);

InvCipher( buffer, expandedKey );

//XORBytes( buffer, chainBlock, BLOCKSIZE );

CopyBytes( chainBlock, buffer, BLOCKSIZE );

}

//对一个16字节块完成加密，参数buffer是加密缓存，chainBlock是要加密的块

void aesEncrypt( unsigned char * buffer, unsigned char * chainBlock )

{

CopyBytes( buffer, chainBlock, BLOCKSIZE );

//XORBytes( buffer, chainBlock, BLOCKSIZE );

Cipher( buffer, expandedKey );

CopyBytes( chainBlock, buffer, BLOCKSIZE );

}

//加解密函数，参数为加解密标志，要加解密的数据缓存起始指针，要加解密的数据长度（如果解密运算，必须是16的整数倍。）

unsigned char aesBlockDecrypt(bit Direct,unsigned char *ChiperDataBuf,unsigned char DataLen)

{

unsigned char xdata i;

unsigned char xdata Blocks;

unsigned char xdata sBoxbuf[256];

unsigned char xdata tempbuf[16];

unsigned long int xdata OrignLen=0; //未加密数据的原始长度

if(Direct==0)

{

*((unsigned char *)&OrignLen+3)=ChiperDataBuf[0];

*((unsigned char *)&OrignLen+2)=ChiperDataBuf[1];

*((unsigned char *)&OrignLen+1)=ChiperDataBuf[2];

*((unsigned char *)&OrignLen)=ChiperDataBuf[3];

DataLen=DataLen-4;

}

else

{

memmove(ChiperDataBuf+4,ChiperDataBuf,DataLen);

OrignLen=DataLen;

ChiperDataBuf[0]=OrignLen;

ChiperDataBuf[1]=OrignLen>>8;

ChiperDataBuf[2]=OrignLen>>16;

ChiperDataBuf[3]=OrignLen>>24;

}

cleardog();

aesInit(sBoxbuf); //初始化

if(Direct==0) //解密

{

Blocks=DataLen/16;

for(i=0;i{

cleardog();

aesDecrypt(tempbuf,ChiperDataBuf+4+16*i);

}

memmove(ChiperDataBuf,ChiperDataBuf+4,OrignLen);

cleardog();

return(OrignLen);

}

else //加密

{

if(DataLen%16!=0)

{

Blocks=DataLen/16+1;

//memset(ChiperDataBuf+4+Blocks*16-(DataLen%16),0x00,DataLen%16); //不足16字节的块补零处理

}

else

{

Blocks=DataLen/16;

}

for(i=0;i{

cleardog();

aesEncrypt(tempbuf,ChiperDataBuf+4+16*i);

}

cleardog();

return(Blocks*16+4);

}

}

//#endif

以上是C文件。以下是头文件

#ifndef AES_H

#define AES_H

extern void aesInit( unsigned char * tempbuf );

extern void aesDecrypt(unsigned char *buffer, unsigned char *chainBlock);

extern void aesEncrypt( unsigned char * buffer, unsigned char * chainBlock );

extern void aesInit( unsigned char * tempbuf );

extern void aesDecrypt( unsigned char * buffer, unsigned char * chainBlock );

extern void aesEncrypt( unsigned char * buffer, unsigned char * chainBlock );

extern unsigned char aesBlockDecrypt(bit Direct,unsigned char *ChiperDataBuf,unsigned char DataLen);

#endif // AES_H

这是我根据网上程序改写的。只支持128位加解密。没有使用占内存很多的查表法。故运算速度会稍慢。