本文目錄一覽:
- 1、ASE加密算法,C語言實現
- 2、如何用C語言編寫暴力破解壓縮文件解壓密碼的程序
- 3、求AES算法加密C語言完整程序
- 4、AES算法C語言實現,C++不要,求幫助
- 5、【密碼學】C語言實現AES核心步驟
- 6、初學者,求高手給一個完整的AES加密解密算法的程序(C/C++) 希望能滿足如下要求
ASE加密算法,C語言實現
Rijdeal的AES算法吧?
實現:
#include”stdio.h”
typedef unsigned char word8;
typedef unsigned int word32;
word8 Logtable[256] =
{
0,0,25,1,50,2,26,198,75,199,27,104,51,238,223,3,100,4,
224,14,52,141,129,239,76,113,8,200,248,105,28,193,125,194,29,
181,249,185,39,106,77,228,166,114,154,201,9,120,101,47,138,
5,33,15,225,36,18,240,130,69,53,147,218,142,150,143,219,189,
54,208,206,148,19,92,210,241,64,70,131,56,102,221,253,48,
191,6,139,98,179,37,226,152,34,136,145,16,126,110,72,195,163,
182,30,66,58,107,40,84,250,133,61,186,43,121,10,21,155,159,
94,202,78,212,172,229,243,115,167,87,175,88,168,80,244,234,
214,116,79,174,233,213,231,230,173,232,44,215,117,122,235,
22,11,245,89,203,95,176,156,169,81,160,127,12,246,111,23,196,
73,236,216,67,31,45,164,118,123,183,204,187,62,90,251,96,
177,134,59,82,161,108,170,85,41,157,151,178,135,144,97,190,
220,252,188,149,207,205,55,63,91,209,83,57,132,60,65,162,109,
71,20,42,158,93,86,242,211,171,68,17,146,217,35,32,46,137,
180,124,184,38,119,153,227,165,103,74,237,222,197,49,254,
24,13,99,140,128,192,247,112,7,
};
word8 Alogtable[256]=
{
1,3,5,15,17,51,85,255,26,46,114,150,161,248,19,53,95,225,
56,72,216,115,149,164,247,2,6,10,30,34,102,170,229,52,92,
228,55,89,235,38,106,190,217,112,144,171,230,49,83,245,4,12,
20,60,68,204,79,209,104,184,211,110,178,205,76,212,103,169,
224,59,77,215,98,166,241,8,24,40,120,136,131,158,185,208,107,
189,220,127,129,152,179,206,73,219,118,154,181,196,87,249,
16,48,80,240,11,29,39,105,187,214,97,163,254,25,43,125,135,
146,173,236,47,113,147,174,233,32,96,160,251,22,58,78,210,
109,183,194,93,231,50,86,250,21,63,65,195,94,226,61,71,201,
64,192,91,237,44,116,156,191,218,117,159,186,213,100,172,239,
42,126,130,157,188,223,122,142,137,128,155,182,193,88,232,
35,101,175,234,37,111,177,200,67,197,84,252,31,33,99,165,
244,7,9,27,45,119,153,176,203,70,202,69,207,74,222,121,139,
134,145,168,227,62,66,198,81,243,14,18,54,90,238,41,123,141,
140,143,138,133,148,167,242,13,23,57,75,221,124,132,151,162,
253,28,36,108,199,82,246,1,
};
word8 S[256]=
{
99,124,119,123,242,107,111,197,48,1,103,43,254,215,171,
118,202,130,201,125,250,89,71,240,173,212,162,175,156,164,
114,192,183,253,147,38,54,63,247,204,52,165,229,241,113,216,
49,21,4,199,35,195,24,150,5,154,7,18,128,226,235,39,178,117,
9,131,44,26,27,110,90,160,82,59,214,179,41,227,47,132,83,209,
0,237,32,252,177,91,106,203,190,57,74,76,88,207,208,239,
170,251,67,77,51,133,69,249,2,127,80,60,159,168,81,163,64,143,
146,157,56,245,188,182,218,33,16,255,243,210,205,12,19,236,
95,151,68,23,196,167,126,61,100,93,25,115,96,129,79,220,
34,42,144,136,70,238,184,20,222,94,11,219,224,50,58,10,73,6,
36,92,194,211,172,98,145,149,228,121,231,200,55,109,141,213,
78,169,108,86,244,234,101,122,174,8,186,120,37,46,28,166,
180,198,232,221,116,31,75,189,139,138,112,62,181,102,72,3,246,
14,97,53,87,185,134,193,29,158,225,248,152,17,105,217,142,
148,155,30,135,233,206,85,40,223,140,161,137,13,191,230,66,
104,65,153,45,15,176,84,187,22,
};
word8 Si[256]=
{
82,9,106,213,48,54,165,56,191,64,163,158,129,243,215,251,
124,227,57,130,155,47,255,135,52,142,67,68,196,222,233,203,
84,123,148,50,166,194,35,61,238,76,149,11,66,250,195,78,8,
46,161,102,40,217,36,178,118,91,162,73,109,139,209,37,114,
248,246,100,134,104,152,22,212,164,92,204,93,101,182,146,108,
112,72,80,253,237,185,218,94,21,70,87,167,141,157,132,144,
216,171,0,140,188,211,10,247,228,88,5,184,179,69,6,208,44,
30,143,202,63,15,2,193,175,189,3,1,19,138,107,58,145,17,65,
79,103,220,234,151,242,207,206,240,180,230,115,150,172,116,
34,231,173,53,133,226,249,55,232,28,117,223,110,71,241,26,
113,29,41,197,137,111,183,98,14,170,24,190,27,252,86,62,75,
198,210,121,32,154,219,192,254,120,205,90,244,31,221,168,51,
136,7,199,49,177,18,16,89,39,128,236,95,96,81,127,169,25,181,
74,13,45,229,122,159,147,201,156,239,160,224,59,77,174,42,
245,176,200,235,187,60,131,83,153,97,23,43,4,126,186,119,
214,38,225,105,20,99,85,33,12,125,
};
word32 Rc[30]=
{
0x00,0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80,0x1B,0x36,
0x6C,0xD8,0xAB,0x4D,0x9A,0x2F,0x5E,0xBC,0x63,0x97,0x35,
0x6A,0xD4,0xB3,0x7D,0xFA,0xEF,0xC5
};
#define MAXBC 8
#define MAXKC 8
#define MAXROUNDS 14
static word8 shifts[5][4]={
0,1,2,3,
0,1,2,3,
0,1,2,3,
0,1,2,4,
0,1,3,4,};
static int numrounds[5][5]={
10,11,12,13,14,
11,11,12,13,14,
12,12,12,13,14,
13,13,13,13,14,
14,14,14,14,14,};
int BC,KC,ROUNDS;
word8 mul(word8 a, word8 b){
//multiply two elements of GF(256)
//required for MixColumns and InvMixColumns
if (ab) return Alogtable[(Logtable[a]+Logtable[b])%255];
else return 0;
}
void AddRoundKey(word8 a[4][MAXBC],word8 rk[4][MAXBC])
{
//XOR corresponding text input and round key input bytes
int i,j;
for(i=0;i4;i++)
for(j=0;jBC;j++)
a[i][j]^=rk[i][j];
}
void SubBytes(word8 a[4][MAXBC],word8 box[256]){
//replace every byte if the input by the byte at that place
//in the non-linear S-box
int i,j;
for(i=0;i4;i++)
for(j=0;iBC;j++)
a[i][j]=box[a[i][j]];
}
void ShiftRows(word8 a[4][MAXBC],word8 d){
//row 0 remains unchanged
//the other three rows are shifted a variable amount
word8 tmp[MAXBC];
int i,j;
if(d==0){
for(i=0;i4;i++){
for(j=0;jBC;j++)
tmp[j]=a[i][(j+shifts[BC-4][i])%BC];
for(j=0;jBC;j++) a[i][j]=tmp[j];
}
}
else {
for (i=0;i4;i++){
for(j=0;jBC;j++)
tmp[j]=a[i][(BC+j-shifts[BC-4][i])%BC];
for(j=0;jBC;j++)
a[i][j]=tmp[j];
}
}
}
int main()
{
return 0;
}
密碼製作者Joan Daemen和Vincent Rijmen的書上看到的,版權歸出版商和作者,轉載請註明出處
如何用C語言編寫暴力破解壓縮文件解壓密碼的程序
由於有一個重要的Rar文件,極需解開,首先試用了ARPC,但是解壓的速度極慢,每秒只有30個左右,所以斷了窮舉破解的念頭,卻仍不死心,因為我從不崇尚窮舉破解的方法,除非每秒可以跑幾千萬次的,我或許可以一試,所以決定研究一下Winrar 3.x密碼算法,以期是否可以破解該密碼。查看了網絡上的資料,包括看雪FAQ里的回答,都聲稱只能用窮舉法破解,起先並不理解,但通過研究,我理解了看雪前輩們在FAQ里所說的原因,不禁讓我佩服
Winrar加密思路的成熟。雖然研究的結果沒有什麼新意,但我還是決定把我的研究結果與大家一起分享,為那些仍然以為winrar密碼可以象破解註冊碼一樣的,通過修改winrar彈出框之類的更改文件流程指向可以達到跳過密碼檢驗的朋友,做一個簡要的說明。
一、Rar文件生成的流程。
Winrar加密文件時,總的分兩個步驟:
1:先把源文件壓縮,壓成一段數據段。
2:再將壓縮完的數據段加密。
對於同一個源文件來說,不進行加密,壓縮完,其rar文件中的數據段是一模一樣的。但是如果對同一個源文件來說,即使使用同一個密碼,加密完rar文件中的數據段是不一樣的,這是由於加密的密鑰是依賴於一個Salt(8個字節的密鑰,用來加密時使用,存放在rar文件頭中里)
所以要解密rar加密文件關鍵在於數據解密這一步,那我們接下來研究一下如何加密的。
二、加密“壓縮完的數據段”的流程
1、獲取密鑰:
將明文的密碼與Salt一起,通過HASH算法,生成兩個16字節的密鑰。(一個是KEY(AES算法的參數),一個是initVector)
2、以Key和initVector來加密壓縮數據:
這裡,是一個循環加密的結構,每16字節作為一個塊,進行加密(這可能正是為什麼加密完的文件長度總為16倍數的原因)。加密採用AES算法(RAR採用的是AES的rijndael的標準應用)。這裡注意:AES加密前,有一個異或運算,是先將每16字節塊與上一個16字節塊加密結果進行異或,然後再進行AES算法的。我用一個簡單的示意代碼看說明:
;===============================================
packblock[0]=packblock[i]^initVector
encryptBlock[0]=AES(packblock[0]) ;(KEY為AES的密鑰)
for i=1 to 塊數量-1
packblock[i]=packblock[i]^encryptBlock[i-1]
encryptBlock[i]=AES(packblock[i]) ;(KEY為AES的密鑰)
next
;packblock[i]表示壓縮完的每16字節數據
;encryptBlock[i]表示加密完的每16字節數據
;===============================================
三、解密的過程
由於AES算法是對稱的,所以解密的過程,是加密過程的逆運算。但解密時AES算法過程與加密所用的不一樣(是因為解密過程中由KEY生成的子密鑰表不一樣)。仍然需要我們將密碼輸入,與salt一起生成兩個16字節密鑰,KEY和initVector。
;===============================================
packblock[0]=AES1(encryptBlock[0]) ;(KEY為AES的密鑰)
packblock[0]=packblock[i]^initVector
for i=1 to 塊數量-1
packblock[i]=AES1(encryptBlock[i]) ;(KEY為AES的密鑰)
packblock[i]=packblock[i]^encryptBlock[i-1]
next
;===============================================
那判斷密碼是否正確的在什麼地方呢?
解密的過程是解密後的數據塊進行解壓縮,然後解成源文件,對該文件進行CRC校驗,存在RAR文件中的源文件CRC校驗碼比較,相同則密碼正確,不相同則密碼錯誤。
四、無法秒破的原因
從上面,我們了解了RAR文件的整體思路。地球人都知道,解密時,肯定有個步驟是來判斷密碼的正確與否。而且,依據以往的經驗,我們也許可以將某些判斷的點移動,那樣可以縮減破解的流程思路。那RAR的這一步在哪裡?它把校驗放在了最後的一步。如果要秒破,我們該怎麼做泥?至少我認為目前是不可能的。
我們從解密過程逆反過來看看:
1、CRC檢驗這一塊修改跳轉?根本毫無意義,因為它已經是最後一步了。你可以修改RAR文件頭的CRC值,你可以將它改得和你用任意密碼解壓出來的文件CRC值一樣,但你的文件根本就不是原來的文件了。可能已經完全面目全非了。所以,對這一過程不可行。CRC校驗本身是不可逆的
2、那麼把判斷提前到壓縮完的數據?
解壓的時候,有沒有什麼來判斷壓縮數據是否正確?壓縮完的數據,有沒有固定的特徵,是否可以做為解壓的判斷,在這一步里,我們也無法找到有效的可用的固定特徵。因為這一步涉及到RAR的壓縮算法。即使一個源文件,即使你的文件前一部分是完全相同的,只對後面的部分進行改過,那麼壓縮完,數據也是完全一樣的。因為壓縮完的數據首先是一個壓縮表,後面是編碼。文件不一樣,掃描完的壓縮表也不一樣,編碼又是依賴於壓縮表,所以,這裡頭找不到壓縮完的數據有任何的固定特徵可以用來判斷的。
不管壓縮數據是什麼樣的,Winrar都一如既往地進行解壓,沒有進行壓縮數據是否有效的判斷。
3、那假如我們破解了AES了泥?
由於AES只依賴於KEY,如果AES算法被破解了,我們知道了KEY,我們可以解出壓縮完的數據,但是這裡有一個問題,還有一個initVector密鑰,用來第一個16字節塊的異或,你沒有initVector參數,你第一個16字節塊的數據便無法解得出來。
4、那就只能從第一步Hash的算法入手
即使你能破解hash,但hash後的結果泥?沒有結果,你怎麼返推密碼。
所以綜上,我發現rar的加密是由hash和AES兩種算法互相牽制,而兩種算法當前都無法破解,至少目前還沒有辦法秒破,也理解了看雪高手講的道理。
五、對窮舉提高算法效率的一些設想。
我用彙編寫完了RAR窮舉解密的算法模塊,但是如何提高效率,優化窮舉的速度泥?我有如下的想法:
1、從壓縮數據里找尋特徵,省掉解壓縮、CRC檢驗代碼和生成initVector生成代碼。目前,通過多次實驗,我找到的一個特徵(不知道這個是否正確),即解密完的最後一個16字節塊的最後一個字節必須為0。因為經過多次的試驗,我發現有加密的數據段長度都會比未加密前的數據長,那麼,最後一個
16個字節的數據塊解密完,多出的部分就都為0,但多出幾個字節泥?多次實驗,長度不一,我試想着從加密數據段最後一個16個字節塊着手,只解這一塊,看是否一個字節為0,這樣,只解密16個字節的數據,來大大提高效率?如果能進行到這一步了,再通過解全部數據,進行CRC校驗的判斷。
2、如果第一個特徵不成立的話,針對特定格式的壓縮文件,比如doc、jpg等,部分數據固定,壓縮完的數據是否存在相互牽制的數據?從而把判斷提前,這一步,我不知道如何找到壓縮完的數據是否存在相互牽制的數據。
求AES算法加密C語言完整程序
恰好我有。能運行的,C語言的。
#include string.h
#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 = (temp1) | (temp7);
// 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;
//以下為加解密密碼,共16字節。可以選擇任意值
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 ) //完成一個塊(16字節,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用來存貯密碼錶
KeyExpansion( expandedKey );
sBoxInv = block2; // Must be block2. block2至此開始只用來存貯SBOXINV
CalcSBoxInv( sBox, sBoxInv );
}
//對一個16字節塊解密,參數buffer是解密密緩存,chainBlock是要解密的塊
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 );
}
//對一個16字節塊完成加密,參數buffer是加密緩存,chainBlock是要加密的塊
void aesEncrypt( unsigned char * buffer, unsigned char * chainBlock )
{
CopyBytes( buffer, chainBlock, BLOCKSIZE );
//XORBytes( buffer, chainBlock, BLOCKSIZE );
Cipher( buffer, expandedKey );
CopyBytes( chainBlock, buffer, BLOCKSIZE );
}
//加解密函數,參數為加解密標誌,要加解密的數據緩存起始指針,要加解密的數據長度(如果解密運算,必須是16的整數倍。)
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; //未加密數據的原始長度
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]=OrignLen8;
ChiperDataBuf[2]=OrignLen16;
ChiperDataBuf[3]=OrignLen24;
}
cleardog();
aesInit(sBoxbuf); //初始化
if(Direct==0) //解密
{
Blocks=DataLen/16;
for(i=0;iBlocks;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字節的塊補零處理
}
else
{
Blocks=DataLen/16;
}
for(i=0;iBlocks;i++)
{
cleardog();
aesEncrypt(tempbuf,ChiperDataBuf+4+16*i);
}
cleardog();
return(Blocks*16+4);
}
}
//#endif
以上是C文件。以下是頭文件
#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
這是我根據網上程序改寫的。只支持128位加解密。沒有使用占內存很多的查表法。故運算速度會稍慢。
AES算法C語言實現,C++不要,求幫助
網上好多嘛
沒有做過優化的一抓一大把
隨便搜一搜及出來了,還拿100分在這裡懸賞
【密碼學】C語言實現AES核心步驟
按照AES算法,完成AES算法S盒、行移位、列混合、輪密鑰加操作
高級加密標準(英語:Advanced Encryption Standard,縮寫:AES),在密碼學中又稱Rijndael加密法,是美國聯邦政府採用的一種區塊加密標準。這個標準用來替代原先的DES,已經被多方分析且廣為全世界所使用。經過五年的甄選流程,高級加密標準由美國國家標準與技術研究院(NIST)於2001年11月26日發佈於FIPS PUB 197,並在2002年5月26日成為有效的標準。2006年,高級加密標準已然成為對稱密鑰加密中最流行的算法之一。
AES採用對稱分組密碼體制,密鑰的長度最少支持為128、192、256,分組長度128位,算法應易於各種硬件和軟件實現。
AES加密數據塊分組長度必須為128比特,密鑰長度可以是128比特、192比特、256比特中的任意一個(如果數據塊及密鑰長度不足時,會補齊)。AES加密有很多輪的重複和變換。大致步驟如下:1、密鑰擴展(KeyExpansion),2、初始輪(Initial Round),3、重複輪(Rounds),每一輪又包括:字節替代(SubBytes)、行移位(ShiftRows)、列混合(MixColumns)、輪密鑰加(AddRoundKey),4、最終輪(Final Round),最終輪沒有MixColumns。
AES算法的加密整體結構
字節替代(SubBytes):使用一個S盒進行非線性置換,S盒是一個16×16的矩陣,如表4-9所示。字節替代將輸入的狀態矩陣的每一個字節通過一個簡單查表操作,映射為另外一個字節。
輸入字節的前4bits指定S盒的行值,後4bits指定S盒的列值,行和列所確定S盒位置的元素作為輸出,例如輸入字節“03”,行值為0,列值為3,根據表4-9可知第0行第3列對應的值為 “7B”,因此輸出字節為“7B”。
舉例
在上面的示例中,第1個基本元素為”F5”,它將被S盒行為第”F行”、列為第”5”列的元素“E6“代替,其餘的輸出也用相同的方法確定。
狀態陣列的4個行循環以字節為基本單位進行左移,而每行循環做移的偏移量是由明文分組的大小和所在行數共同確定,即列數Nb和行號確定。
舉例
舉例
輪密鑰加操作是將密鑰與明文按比特異或,輪密鑰通過密鑰擴展得到
和fips-192(AES)的標準一樣
初學者,求高手給一個完整的AES加密解密算法的程序(C/C++) 希望能滿足如下要求
/*128bits密鑰長度及分組長度AES加解密代碼
*作者:Jeffrey.zhu
*/
原創文章,作者:小藍,如若轉載,請註明出處:https://www.506064.com/zh-hant/n/181903.html