aes.rar_AES_AES C程序_AES算法_VC++ AES_aes vc

/* Rijndael Block Cipher - rijndael.c Edited by Jianqin Zhou 28th April 2004 Written by Mike Scott 21st April 1999 mike@compapp.dcu.ie An alternative faster version is implemented in MIRACL ftp://ftp.computing.dcu.ie/pub/crypto/miracl.zip Copyright (c) 1999 Mike Scott Simply compile and run, e.g. cl /O2 rijndael.c (Microsoft C) bcc32 /O2 rijndael.c (Borland C) gcc -O2 rijndael.c -o rijndael (Gnu C) Compiles and runs fine as a C++ program also. See rijndael documentation. The code follows the documentation as closely as possible, and where possible uses the same function and variable names. Permission for free direct or derivative use is granted subject to compliance with any conditions that the originators of the algorithm place on its exploitation. Inspiration from Brian Gladman's implementation is acknowledged. Written for clarity, rather than speed. Assumes long is 32 bit quantity. Full implementation. Endian indifferent. */ #include <stdio.h> #define BYTE unsigned char /* 8 bits */ #define WORD unsigned long /* 32 bits */ /* rotates x one bit to the left */ #define ROTL(x) (((x)>>7)|((x)<<1)) /* Rotates 32-bit word left by 1, 2 or 3 byte */ #define ROTL8(x) (((x)<<8)|((x)>>24)) #define ROTL16(x) (((x)<<16)|((x)>>16)) #define ROTL24(x) (((x)<<24)|((x)>>8)) /* Fixed Data */ static BYTE InCo[4]={0xB,0xD,0x9,0xE}; /* Inverse Coefficients */ static BYTE fbsub[256]; static BYTE rbsub[256]; static BYTE ptab[256],ltab[256]; static WORD ftable[256]; static WORD rtable[256]; static WORD rco[30]; /* Parameter-dependent data */ int Nk,Nb,Nr; BYTE fi[24],ri[24]; WORD fkey[120]; WORD rkey[120]; static WORD pack(BYTE *b) { /* pack bytes into a 32-bit Word */ return ((WORD)b[3]<<24)|((WORD)b[2]<<16)|((WORD)b[1]<<8)|(WORD)b[0]; } static void unpack(WORD a,BYTE *b) { /* unpack bytes from a word */ b[0]=(BYTE)a; b[1]=(BYTE)(a>>8); b[2]=(BYTE)(a>>16); b[3]=(BYTE)(a>>24); } //关于模多项式0x011b的乘10b运算 static BYTE xtime(BYTE a) { BYTE b; if (a&0x80) b=0x1B; else b=0; a<<=1; a^=b; return a; } static BYTE bmul(BYTE x,BYTE y) { /* x.y= AntiLog(Log(x) + Log(y)) */ if (x && y) return ptab[(ltab[x]+ltab[y])%255]; else return 0; } static WORD SubByte(WORD a) { BYTE b[4]; unpack(a,b); b[0]=fbsub[b[0]]; b[1]=fbsub[b[1]]; b[2]=fbsub[b[2]]; b[3]=fbsub[b[3]]; return pack(b); } static BYTE product(WORD x,WORD y) { /* dot product of two 4-byte arrays */ BYTE xb[4],yb[4]; unpack(x,xb); unpack(y,yb); return bmul(xb[0],yb[0])^bmul(xb[1],yb[1])^bmul(xb[2],yb[2])^bmul(xb[3],yb[3]); } static WORD InvMixCol(WORD x) { /* matrix Multiplication */ WORD y,m; BYTE b[4]; m=pack(InCo); b[3]=product(m,x); m=ROTL24(m); b[2]=product(m,x); m=ROTL24(m); b[1]=product(m,x); m=ROTL24(m); b[0]=product(m,x); y=pack(b); return y; } BYTE ByteSub(BYTE x) { BYTE y=ptab[255-ltab[x]]; /* multiplicative inverse */ x=y; x=ROTL(x); y^=x; x=ROTL(x); y^=x; x=ROTL(x); y^=x; x=ROTL(x); y^=x; y^=0x63; return y; } void gentables(void) { /* generate tables */ int i; BYTE y,b[4]; /* use 3 as primitive root to generate power and log tables */ ltab[0]=0; ptab[0]=1; ltab[1]=0; ptab[1]=3; ltab[3]=1; for (i=2;i<256;i++) { ptab[i]=ptab[i-1]^xtime(ptab[i-1]); ltab[ptab[i]]=i; } /* affine transformation:- each bit is xored with itself shifted one bit 仿射变换 */ fbsub[0]=0x63; rbsub[0x63]=0; for (i=1;i<256;i++) { y=ByteSub((BYTE)i); fbsub[i]=y; rbsub[y]=i; } for (i=0,y=1;i<30;i++) { rco[i]=y; y=xtime(y); } /* calculate forward and reverse tables */ for (i=0;i<256;i++) { y=fbsub[i]; b[3]=y^xtime(y); b[2]=y; b[1]=y; b[0]=xtime(y); ftable[i]=pack(b); y=rbsub[i]; b[3]=bmul(InCo[0],y); b[2]=bmul(InCo[1],y); b[1]=bmul(InCo[2],y); b[0]=bmul(InCo[3],y); rtable[i]=pack(b); } } void strtoHex(char *str,char *hex) { char ch; int i=0, by = 0; while(i < 64 && *str) // the maximum key length is 32 bytes(256 bits) and { // hence at most 64 hexadecimal digits ch = toupper(*str++); // process a hexadecimal digit if(ch >= '0' && ch <= '9') by = (by << 4) + ch - '0'; else if(ch >= 'A' && ch <= 'F') by = (by << 4) + ch - 'A' + 10; else // error if not hexadecimal { printf("key must be in hexadecimal notation\n"); exit(0); } // store a key byte for each pair of hexadecimal digits if(i++ & 1) hex[i / 2 - 1] = by & 0xff; } } void hextoStr(char *hex,char *str) { int i=0, by = 0; while(i < 32 && *hex) // the maximum key length is 32 bytes(256 bits) and { // hence at most 64 hexadecimal digits by = *hex ; // process a hexadecimal digit(high) by=by>>4 &0x0f; if(by >= 0 && by <= 9) *str++ = by + '0'; else if(by >= 0x0A && by <= 0x0F) *str++ = by - 10+ 'A'; by = *hex++; // process a hexadecimal digit(low) by=by &0x0f; if(by >= 0 && by <= 9) *str++ = by + '0'; else if(by >= 0x0A && by <= 0x0F) *str++ = by - 10+ 'A'; i++; } } void gkey(int nb,int nk,char *key) { /* blocksize=32*nb bits. Key=32*nk bits */ /* currently nb,nk = 4, 6 or 8 */ /* key comes as 4*Nk bytes */ /* Key Scheduler. Create expanded encryption key */ int i,j,k,m,N; int C1,C2,C3; WORD CipherKey[8]; Nb=nb; Nk=nk; /* Nr is number of rounds */ if (Nb>=Nk) Nr=6+Nb; else Nr=6+Nk; C1=1; if (Nb<8) { C2=2; C3=3; } else { C2=3; C3=4; } /* pre-calculate forward and reverse increments */ for (m=j=0;j<nb;j++,m+=3) { fi[m]=(j+C1)%nb; fi[m+1]=(j+C2)%nb; fi[m+2]=(j+C3)%nb; ri[m]=(nb+j-C1)%nb; ri[m+1]=(nb+j-C2)%nb; ri[m+2]=(nb+j-C3)%nb; } N=Nb*(Nr+1); for (i=j=0;i<Nk;i++,j+=4) { CipherKey[i]=pack((BYTE *)&key[j]); } for (i=0;i<Nk;i++) fkey[i]=CipherKey[i]; for (j=Nk,k=0;j<N;j+=Nk,k++) { fkey[j]=fkey[j-Nk]^SubByte(ROTL24(fkey[j-1]))^rco[k]; if (Nk<=6) { for (i=1;i<Nk && (i+j)<N;i++) fkey[i+j]=fkey[i+j-Nk]^fkey[i+j-1]; } else { for (i=1;i<4 &&(i+j)<N;i++) fkey[i+j]=fkey[i+j-Nk]^fkey[i+j-1]; if ((j+4)<N) fkey[j+4]=fkey[j+4-Nk]^SubByte(fkey[j+3]); for (i=5;i<Nk && (i+j)<N;i++) fkey[i+j]=fkey[i+j-Nk]^fkey[i+j-1]; } } /* now for the expanded decrypt key in reverse order */ for (j=0;j<Nb;j++) rkey[j+N-Nb]=fkey[j]; for (i=Nb;i<N-Nb;i+=Nb) { k=N-Nb-i; for (j=0;j<Nb;j++) rkey[k+j]=InvMixCol(fkey[i+j]); } for (j=N-Nb;j<N;j++) rkey[j-N+Nb]=fkey[j]; } /* There is an obvious time/space trade-off possible here. * * Instead of just one ftable[], I could have 4, the other * * 3 pre-rotated to save the ROTL8, ROTL16 and ROTL24 overhead */ void encrypt(char *buff) { int i,j,k,m; WORD a[8],b[8],*x,*y,*t; for (i=j=0;i<Nb;i++,j+=4) { a[i]=pack((BYTE *)&buff[j]); a[i]^