1/* $OpenBSD: rijndael.c,v 1.7 2001/02/04 15:32:24 stevesk Exp $ */ |
2 3/* This is an independent implementation of the encryption algorithm: */ 4/* */ 5/* RIJNDAEL by Joan Daemen and Vincent Rijmen */ 6/* */ 7/* which is a candidate algorithm in the Advanced Encryption Standard */ 8/* programme of the US National Institute of Standards and Technology. */ 9/* */ --- 37 unchanged lines hidden (view full) --- 47 48/* Circular rotate of 32 bit values */ 49 50#define rotr(x,n) (((x) >> ((int)(n))) | ((x) << (32 - (int)(n)))) 51#define rotl(x,n) (((x) << ((int)(n))) | ((x) >> (32 - (int)(n)))) 52 53/* Invert byte order in a 32 bit variable */ 54 |
55#define bswap(x) ((rotl(x, 8) & 0x00ff00ff) | (rotr(x, 8) & 0xff00ff00)) |
56 |
57/* Extract byte from a 32 bit quantity (little endian notation) */ |
58 59#define byte(x,n) ((u1byte)((x) >> (8 * n))) 60 61#if BYTE_ORDER != LITTLE_ENDIAN |
62#define BYTE_SWAP |
63#endif 64 65#ifdef BYTE_SWAP 66#define io_swap(x) bswap(x) 67#else 68#define io_swap(x) (x) 69#endif 70 |
71#define LARGE_TABLES 72 73u1byte pow_tab[256]; 74u1byte log_tab[256]; 75u1byte sbx_tab[256]; 76u1byte isb_tab[256]; 77u4byte rco_tab[ 10]; 78u4byte ft_tab[4][256]; --- 5 unchanged lines hidden (view full) --- 84#endif 85 86u4byte tab_gen = 0; 87 88#define ff_mult(a,b) (a && b ? pow_tab[(log_tab[a] + log_tab[b]) % 255] : 0) 89 90#define f_rn(bo, bi, n, k) \ 91 bo[n] = ft_tab[0][byte(bi[n],0)] ^ \ |
92 ft_tab[1][byte(bi[(n + 1) & 3],1)] ^ \ 93 ft_tab[2][byte(bi[(n + 2) & 3],2)] ^ \ 94 ft_tab[3][byte(bi[(n + 3) & 3],3)] ^ *(k + n) |
95 96#define i_rn(bo, bi, n, k) \ 97 bo[n] = it_tab[0][byte(bi[n],0)] ^ \ |
98 it_tab[1][byte(bi[(n + 3) & 3],1)] ^ \ 99 it_tab[2][byte(bi[(n + 2) & 3],2)] ^ \ 100 it_tab[3][byte(bi[(n + 1) & 3],3)] ^ *(k + n) |
101 102#ifdef LARGE_TABLES 103 104#define ls_box(x) \ 105 ( fl_tab[0][byte(x, 0)] ^ \ 106 fl_tab[1][byte(x, 1)] ^ \ 107 fl_tab[2][byte(x, 2)] ^ \ 108 fl_tab[3][byte(x, 3)] ) 109 110#define f_rl(bo, bi, n, k) \ 111 bo[n] = fl_tab[0][byte(bi[n],0)] ^ \ |
112 fl_tab[1][byte(bi[(n + 1) & 3],1)] ^ \ 113 fl_tab[2][byte(bi[(n + 2) & 3],2)] ^ \ 114 fl_tab[3][byte(bi[(n + 3) & 3],3)] ^ *(k + n) |
115 116#define i_rl(bo, bi, n, k) \ 117 bo[n] = il_tab[0][byte(bi[n],0)] ^ \ |
118 il_tab[1][byte(bi[(n + 3) & 3],1)] ^ \ 119 il_tab[2][byte(bi[(n + 2) & 3],2)] ^ \ 120 il_tab[3][byte(bi[(n + 1) & 3],3)] ^ *(k + n) |
121 122#else 123 124#define ls_box(x) \ 125 ((u4byte)sbx_tab[byte(x, 0)] << 0) ^ \ 126 ((u4byte)sbx_tab[byte(x, 1)] << 8) ^ \ 127 ((u4byte)sbx_tab[byte(x, 2)] << 16) ^ \ 128 ((u4byte)sbx_tab[byte(x, 3)] << 24) 129 130#define f_rl(bo, bi, n, k) \ 131 bo[n] = (u4byte)sbx_tab[byte(bi[n],0)] ^ \ |
132 rotl(((u4byte)sbx_tab[byte(bi[(n + 1) & 3],1)]), 8) ^ \ 133 rotl(((u4byte)sbx_tab[byte(bi[(n + 2) & 3],2)]), 16) ^ \ 134 rotl(((u4byte)sbx_tab[byte(bi[(n + 3) & 3],3)]), 24) ^ *(k + n) |
135 136#define i_rl(bo, bi, n, k) \ 137 bo[n] = (u4byte)isb_tab[byte(bi[n],0)] ^ \ |
138 rotl(((u4byte)isb_tab[byte(bi[(n + 3) & 3],1)]), 8) ^ \ 139 rotl(((u4byte)isb_tab[byte(bi[(n + 2) & 3],2)]), 16) ^ \ 140 rotl(((u4byte)isb_tab[byte(bi[(n + 1) & 3],3)]), 24) ^ *(k + n) |
141 142#endif 143 144void 145gen_tabs(void) 146{ 147 u4byte i, t; 148 u1byte p, q; --- 6 unchanged lines hidden (view full) --- 155 pow_tab[i] = (u1byte)p; log_tab[p] = (u1byte)i; 156 157 p = p ^ (p << 1) ^ (p & 0x80 ? 0x01b : 0); 158 } 159 160 log_tab[1] = 0; p = 1; 161 162 for(i = 0; i < 10; ++i) { |
163 rco_tab[i] = p; |
164 165 p = (p << 1) ^ (p & 0x80 ? 0x1b : 0); 166 } 167 168 /* note that the affine byte transformation matrix in */ 169 /* rijndael specification is in big endian format with */ 170 /* bit 0 as the most significant bit. In the remainder */ 171 /* of the specification the bits are numbered from the */ 172 /* least significant end of a byte. */ 173 174 for(i = 0; i < 256; ++i) { |
175 p = (i ? pow_tab[255 - log_tab[i]] : 0); q = p; 176 q = (q >> 7) | (q << 1); p ^= q; 177 q = (q >> 7) | (q << 1); p ^= q; 178 q = (q >> 7) | (q << 1); p ^= q; 179 q = (q >> 7) | (q << 1); p ^= q ^ 0x63; |
180 sbx_tab[i] = (u1byte)p; isb_tab[p] = (u1byte)i; 181 } 182 183 for(i = 0; i < 256; ++i) { |
184 p = sbx_tab[i]; |
185 |
186#ifdef LARGE_TABLES 187 |
188 t = p; fl_tab[0][i] = t; 189 fl_tab[1][i] = rotl(t, 8); 190 fl_tab[2][i] = rotl(t, 16); 191 fl_tab[3][i] = rotl(t, 24); 192#endif 193 t = ((u4byte)ff_mult(2, p)) | 194 ((u4byte)p << 8) | 195 ((u4byte)p << 16) | 196 ((u4byte)ff_mult(3, p) << 24); |
197 |
198 ft_tab[0][i] = t; 199 ft_tab[1][i] = rotl(t, 8); 200 ft_tab[2][i] = rotl(t, 16); 201 ft_tab[3][i] = rotl(t, 24); 202 |
203 p = isb_tab[i]; |
204 |
205#ifdef LARGE_TABLES 206 207 t = p; il_tab[0][i] = t; 208 il_tab[1][i] = rotl(t, 8); 209 il_tab[2][i] = rotl(t, 16); |
210 il_tab[3][i] = rotl(t, 24); |
211#endif |
212 t = ((u4byte)ff_mult(14, p)) | 213 ((u4byte)ff_mult( 9, p) << 8) | 214 ((u4byte)ff_mult(13, p) << 16) | 215 ((u4byte)ff_mult(11, p) << 24); |
216 217 it_tab[0][i] = t; 218 it_tab[1][i] = rotl(t, 8); 219 it_tab[2][i] = rotl(t, 16); 220 it_tab[3][i] = rotl(t, 24); |
221 } 222 223 tab_gen = 1; 224} 225 226#define star_x(x) (((x) & 0x7f7f7f7f) << 1) ^ ((((x) & 0x80808080) >> 7) * 0x1b) 227 228#define imix_col(y,x) \ 229 u = star_x(x); \ 230 v = star_x(u); \ 231 w = star_x(v); \ 232 t = w ^ (x); \ 233 (y) = u ^ v ^ w; \ 234 (y) ^= rotr(u ^ t, 8) ^ \ |
235 rotr(v ^ t, 16) ^ \ 236 rotr(t,24) |
237 238/* initialise the key schedule from the user supplied key */ 239 240#define loop4(i) \ 241{ t = ls_box(rotr(t, 8)) ^ rco_tab[i]; \ 242 t ^= e_key[4 * i]; e_key[4 * i + 4] = t; \ 243 t ^= e_key[4 * i + 1]; e_key[4 * i + 5] = t; \ 244 t ^= e_key[4 * i + 2]; e_key[4 * i + 6] = t; \ --- 21 unchanged lines hidden (view full) --- 266 t ^= e_key[8 * i + 5]; e_key[8 * i + 13] = t; \ 267 t ^= e_key[8 * i + 6]; e_key[8 * i + 14] = t; \ 268 t ^= e_key[8 * i + 7]; e_key[8 * i + 15] = t; \ 269} 270 271rijndael_ctx * 272rijndael_set_key(rijndael_ctx *ctx, const u4byte *in_key, const u4byte key_len, 273 int encrypt) |
274{ |
275 u4byte i, t, u, v, w; 276 u4byte *e_key = ctx->e_key; 277 u4byte *d_key = ctx->d_key; 278 279 ctx->decrypt = !encrypt; 280 281 if(!tab_gen) 282 gen_tabs(); 283 284 ctx->k_len = (key_len + 31) / 32; 285 |
286 e_key[0] = io_swap(in_key[0]); e_key[1] = io_swap(in_key[1]); 287 e_key[2] = io_swap(in_key[2]); e_key[3] = io_swap(in_key[3]); 288 |
289 switch(ctx->k_len) { |
290 case 4: t = e_key[3]; 291 for(i = 0; i < 10; ++i) |
292 loop4(i); |
293 break; |
294 |
295 case 6: e_key[4] = io_swap(in_key[4]); t = e_key[5] = io_swap(in_key[5]); 296 for(i = 0; i < 8; ++i) |
297 loop6(i); |
298 break; |
299 |
300 case 8: e_key[4] = io_swap(in_key[4]); e_key[5] = io_swap(in_key[5]); 301 e_key[6] = io_swap(in_key[6]); t = e_key[7] = io_swap(in_key[7]); 302 for(i = 0; i < 7; ++i) |
303 loop8(i); |
304 break; |
305 } 306 307 if (!encrypt) { 308 d_key[0] = e_key[0]; d_key[1] = e_key[1]; 309 d_key[2] = e_key[2]; d_key[3] = e_key[3]; 310 311 for(i = 4; i < 4 * ctx->k_len + 24; ++i) { 312 imix_col(d_key[i], e_key[i]); --- 15 unchanged lines hidden (view full) --- 328#define f_lround(bo, bi, k) \ 329 f_rl(bo, bi, 0, k); \ 330 f_rl(bo, bi, 1, k); \ 331 f_rl(bo, bi, 2, k); \ 332 f_rl(bo, bi, 3, k) 333 334void 335rijndael_encrypt(rijndael_ctx *ctx, const u4byte *in_blk, u4byte *out_blk) |
336{ |
337 u4byte k_len = ctx->k_len; 338 u4byte *e_key = ctx->e_key; 339 u4byte b0[4], b1[4], *kp; 340 |
341 b0[0] = io_swap(in_blk[0]) ^ e_key[0]; 342 b0[1] = io_swap(in_blk[1]) ^ e_key[1]; 343 b0[2] = io_swap(in_blk[2]) ^ e_key[2]; 344 b0[3] = io_swap(in_blk[3]) ^ e_key[3]; |
345 346 kp = e_key + 4; 347 348 if(k_len > 6) { 349 f_nround(b1, b0, kp); f_nround(b0, b1, kp); 350 } 351 352 if(k_len > 4) { 353 f_nround(b1, b0, kp); f_nround(b0, b1, kp); 354 } 355 356 f_nround(b1, b0, kp); f_nround(b0, b1, kp); 357 f_nround(b1, b0, kp); f_nround(b0, b1, kp); 358 f_nround(b1, b0, kp); f_nround(b0, b1, kp); 359 f_nround(b1, b0, kp); f_nround(b0, b1, kp); 360 f_nround(b1, b0, kp); f_lround(b0, b1, kp); 361 |
362 out_blk[0] = io_swap(b0[0]); out_blk[1] = io_swap(b0[1]); 363 out_blk[2] = io_swap(b0[2]); out_blk[3] = io_swap(b0[3]); |
364} 365 366/* decrypt a block of text */ 367 368#define i_nround(bo, bi, k) \ 369 i_rn(bo, bi, 0, k); \ 370 i_rn(bo, bi, 1, k); \ 371 i_rn(bo, bi, 2, k); \ 372 i_rn(bo, bi, 3, k); \ 373 k -= 4 374 375#define i_lround(bo, bi, k) \ 376 i_rl(bo, bi, 0, k); \ 377 i_rl(bo, bi, 1, k); \ 378 i_rl(bo, bi, 2, k); \ 379 i_rl(bo, bi, 3, k) 380 381void 382rijndael_decrypt(rijndael_ctx *ctx, const u4byte *in_blk, u4byte *out_blk) |
383{ |
384 u4byte b0[4], b1[4], *kp; 385 u4byte k_len = ctx->k_len; 386 u4byte *e_key = ctx->e_key; 387 u4byte *d_key = ctx->d_key; 388 |
389 b0[0] = io_swap(in_blk[0]) ^ e_key[4 * k_len + 24]; 390 b0[1] = io_swap(in_blk[1]) ^ e_key[4 * k_len + 25]; 391 b0[2] = io_swap(in_blk[2]) ^ e_key[4 * k_len + 26]; 392 b0[3] = io_swap(in_blk[3]) ^ e_key[4 * k_len + 27]; |
393 394 kp = d_key + 4 * (k_len + 5); 395 396 if(k_len > 6) { 397 i_nround(b1, b0, kp); i_nround(b0, b1, kp); 398 } 399 400 if(k_len > 4) { 401 i_nround(b1, b0, kp); i_nround(b0, b1, kp); 402 } 403 404 i_nround(b1, b0, kp); i_nround(b0, b1, kp); 405 i_nround(b1, b0, kp); i_nround(b0, b1, kp); 406 i_nround(b1, b0, kp); i_nround(b0, b1, kp); 407 i_nround(b1, b0, kp); i_nround(b0, b1, kp); 408 i_nround(b1, b0, kp); i_lround(b0, b1, kp); 409 |
410 out_blk[0] = io_swap(b0[0]); out_blk[1] = io_swap(b0[1]); 411 out_blk[2] = io_swap(b0[2]); out_blk[3] = io_swap(b0[3]); |
412} |