加密算法简单实用 rijndael

// rijndael.cpp: implementation of the rijndael class. // ////////////////////////////////////////////////////////////////////// #include "stdafx.h" //#include "MainFrm.h" #include "rijndael.h" #ifdef _DEBUG #undef THIS_FILE static char THIS_FILE[]=__FILE__; #define new DEBUG_NEW #endif ////////////////////////////////////////////////////////////////////// // Construction/Destruction ////////////////////////////////////////////////////////////////////// rijndael::rijndael() { } rijndael::~rijndael() { } #define LARGE_TABLES namespace { u1byte pow_tab[256]; u1byte log_tab[256]; u1byte sbx_tab[256]; u1byte isb_tab[256]; u4byte rco_tab[ 10]; u4byte ft_tab[4][256]; u4byte it_tab[4][256]; #ifdef LARGE_TABLES u4byte fl_tab[4][256]; u4byte il_tab[4][256]; #endif u4byte tab_gen = 0; #define ff_mult(a,b) (a && b ? pow_tab[(log_tab[a] + log_tab[b]) % 255] : 0) #define f_rn(bo, bi, n, k) \ bo[n] = ft_tab[0][byte(bi[n],0)] ^ \ ft_tab[1][byte(bi[(n + 1) & 3],1)] ^ \ ft_tab[2][byte(bi[(n + 2) & 3],2)] ^ \ ft_tab[3][byte(bi[(n + 3) & 3],3)] ^ *(k + n) #define i_rn(bo, bi, n, k) \ bo[n] = it_tab[0][byte(bi[n],0)] ^ \ it_tab[1][byte(bi[(n + 3) & 3],1)] ^ \ it_tab[2][byte(bi[(n + 2) & 3],2)] ^ \ it_tab[3][byte(bi[(n + 1) & 3],3)] ^ *(k + n) #ifdef LARGE_TABLES #define ls_box(x) \ ( fl_tab[0][byte(x, 0)] ^ \ fl_tab[1][byte(x, 1)] ^ \ fl_tab[2][byte(x, 2)] ^ \ fl_tab[3][byte(x, 3)] ) #define f_rl(bo, bi, n, k) \ bo[n] = fl_tab[0][byte(bi[n],0)] ^ \ fl_tab[1][byte(bi[(n + 1) & 3],1)] ^ \ fl_tab[2][byte(bi[(n + 2) & 3],2)] ^ \ fl_tab[3][byte(bi[(n + 3) & 3],3)] ^ *(k + n) #define i_rl(bo, bi, n, k) \ bo[n] = il_tab[0][byte(bi[n],0)] ^ \ il_tab[1][byte(bi[(n + 3) & 3],1)] ^ \ il_tab[2][byte(bi[(n + 2) & 3],2)] ^ \ il_tab[3][byte(bi[(n + 1) & 3],3)] ^ *(k + n) #else #define ls_box(x) \ ((u4byte)sbx_tab[byte(x, 0)] << 0) ^ \ ((u4byte)sbx_tab[byte(x, 1)] << 8) ^ \ ((u4byte)sbx_tab[byte(x, 2)] << 16) ^ \ ((u4byte)sbx_tab[byte(x, 3)] << 24) #define f_rl(bo, bi, n, k) \ bo[n] = (u4byte)sbx_tab[byte(bi[n],0)] ^ \ rotl(((u4byte)sbx_tab[byte(bi[(n + 1) & 3],1)]), 8) ^ \ rotl(((u4byte)sbx_tab[byte(bi[(n + 2) & 3],2)]), 16) ^ \ rotl(((u4byte)sbx_tab[byte(bi[(n + 3) & 3],3)]), 24) ^ *(k + n) #define i_rl(bo, bi, n, k) \ bo[n] = (u4byte)isb_tab[byte(bi[n],0)] ^ \ rotl(((u4byte)isb_tab[byte(bi[(n + 3) & 3],1)]), 8) ^ \ rotl(((u4byte)isb_tab[byte(bi[(n + 2) & 3],2)]), 16) ^ \ rotl(((u4byte)isb_tab[byte(bi[(n + 1) & 3],3)]), 24) ^ *(k + n) #endif void gen_tabs(void) { u4byte i, t; u1byte p, q; // log and power tables for GF(2**8) finite field with // 0x011b as modular polynomial - the simplest prmitive // root is 0x03, used here to generate the tables for(i = 0,p = 1; i < 256; ++i) { pow_tab[i] = (u1byte)p; log_tab[p] = (u1byte)i; p = p ^ (p << 1) ^ (p & 0x80 ? 0x01b : 0); } log_tab[1] = 0; p = 1; for(i = 0; i < 10; ++i) { rco_tab[i] = p; p = (p << 1) ^ (p & 0x80 ? 0x1b : 0); } for(i = 0; i < 256; ++i) { p = (i ? pow_tab[255 - log_tab[i]] : 0); q = p; q = (q >> 7) | (q << 1); p ^= q; q = (q >> 7) | (q << 1); p ^= q; q = (q >> 7) | (q << 1); p ^= q; q = (q >> 7) | (q << 1); p ^= q ^ 0x63; sbx_tab[i] = p; isb_tab[p] = (u1byte)i; } for(i = 0; i < 256; ++i) { p = sbx_tab[i]; #ifdef LARGE_TABLES t = p; fl_tab[0][i] = t; fl_tab[1][i] = rotl(t, 8); fl_tab[2][i] = rotl(t, 16); fl_tab[3][i] = rotl(t, 24); #endif t = ((u4byte)ff_mult(2, p)) | ((u4byte)p << 8) | ((u4byte)p << 16) | ((u4byte)ff_mult(3, p) << 24); ft_tab[0][i] = t; ft_tab[1][i] = rotl(t, 8); ft_tab[2][i] = rotl(t, 16); ft_tab[3][i] = rotl(t, 24); p = isb_tab[i]; #ifdef LARGE_TABLES t = p; il_tab[0][i] = t; il_tab[1][i] = rotl(t, 8); il_tab[2][i] = rotl(t, 16); il_tab[3][i] = rotl(t, 24); #endif t = ((u4byte)ff_mult(14, p)) | ((u4byte)ff_mult( 9, p) << 8) | ((u4byte)ff_mult(13, p) << 16) | ((u4byte)ff_mult(11, p) << 24); it_tab[0][i] = t; it_tab[1][i] = rotl(t, 8); it_tab[2][i] = rotl(t, 16); it_tab[3][i] = rotl(t, 24); } tab_gen = 1; } #define star_x(x) (((x) & 0x7f7f7f7f) << 1) ^ ((((x) & 0x80808080) >> 7) * 0x1b) #define imix_col(y,x) \ u = star_x(x); \ v = star_x(u); \ w = star_x(v); \ t = w ^ (x); \ (y) = u ^ v ^ w; \ (y) ^= rotr(u ^ t, 8) ^ \ rotr(v ^ t, 16) ^ \ rotr(t,24) } // end of anonymous namespace char *rijndael::name(void) { return "rijndael"; } // initialise the key schedule from the user supplied key #define loop4(i) \ { t = ls_box(rotr(t, 8)) ^ rco_tab[i]; \ t ^= e_key[4 * i]; e_key[4 * i + 4] = t; \ t ^= e_key[4 * i + 1]; e_key[4 * i + 5] = t; \ t ^= e_key[4 * i + 2]; e_key[4 * i + 6] = t; \ t ^= e_key[4 * i + 3]; e_key[4 * i + 7] = t; \ } #define loop6(i) \ { t = ls_box(rotr(t, 8)) ^ rco_tab[i]; \ t ^= e_key[6 * i]; e_key[6 * i + 6] = t; \ t ^= e_key[6 * i + 1]; e_key[6 * i + 7] = t; \ t ^= e_key[6 * i + 2]; e_key[6 * i + 8] = t; \ t ^= e_key[6 * i + 3]; e_key[6 * i + 9] = t; \ t ^= e_key[6 * i + 4]; e_key[6 * i + 10] = t; \ t ^= e_key[6 * i + 5]; e_key[6 * i + 11] = t; \ } #define loop8(i) \ { t = ls_box(rotr(t, 8)) ^ rco_tab[i]; \ t ^= e_key[8 * i]; e_key[8 * i + 8] = t; \ t ^= e_key[8 * i + 1]; e_key[8 * i + 9] = t; \ t ^= e_key[8 * i + 2]; e_key[8 * i + 10] = t; \ t ^= e_key[8 * i + 3]; e_key[8 * i + 11] = t; \ t = e_key[8 * i + 4] ^ ls_box(t); \ e_key[8 * i + 12] = t; \ t ^= e_key[8 * i + 5]; e_key[8 * i + 13] = t; \ t ^= e_key[8 * i + 6]; e_key[8 * i + 14] = t; \ t ^= e_key[8 * i + 7]; e_key[8 * i + 15] = t; \ } void rijndael::set_key(const u1byte in_key[], const u4byte key_len) { u4byte i, t, u, v, w; if(!tab_gen) gen_tabs(); k_len = (key_len + 31) / 32; e_key[0] = u4byte_in(in_key ); e_key[1] = u4byte_in(in_key + 4); e_key[2] = u4byte_in(in_key + 8); e_key[3] = u4byte_in(in_key + 12); switch(k_len) { case 4: t = e_key[3]; for(i = 0; i < 10; ++i) loop4(i); break; case 6: e_key[4] = u4byte_in(in_key + 16); t = e_key[5] = u4byte_in(in_key + 20); for(i = 0; i < 8; ++i) loop6(i); break; case 8: e_key[4] = u4byte_in(in_key + 16); e_key[5] = u4byte_in(in_key + 20); e_key[6] = u4byte_in(in_key + 24); t = e_key[7] = u4byte_in(in_