/* $OpenBSD: rijndael.c,v 1.6 2000/12/09 18:51:34 markus Exp $ */ /* This is an independent implementation of the encryption algorithm: */ /* */ /* RIJNDAEL by Joan Daemen and Vincent Rijmen */ /* */ /* which is a candidate algorithm in the Advanced Encryption Standard */ /* programme of the US National Institute of Standards and Technology. */ /* */ /* Copyright in this implementation is held by Dr B R Gladman but I */ /* hereby give permission for its free direct or derivative use subject */ /* to acknowledgment of its origin and compliance with any conditions */ /* that the originators of the algorithm place on its exploitation. */ /* */ /* Dr Brian Gladman (gladman@seven77.demon.co.uk) 14th January 1999 */ /* Timing data for Rijndael (rijndael.c) Algorithm: rijndael (rijndael.c) 128 bit key: Key Setup: 305/1389 cycles (encrypt/decrypt) Encrypt: 374 cycles = 68.4 mbits/sec Decrypt: 352 cycles = 72.7 mbits/sec Mean: 363 cycles = 70.5 mbits/sec 192 bit key: Key Setup: 277/1595 cycles (encrypt/decrypt) Encrypt: 439 cycles = 58.3 mbits/sec Decrypt: 425 cycles = 60.2 mbits/sec Mean: 432 cycles = 59.3 mbits/sec 256 bit key: Key Setup: 374/1960 cycles (encrypt/decrypt) Encrypt: 502 cycles = 51.0 mbits/sec Decrypt: 498 cycles = 51.4 mbits/sec Mean: 500 cycles = 51.2 mbits/sec */ #include #include #include void gen_tabs __P((void)); /* 3. Basic macros for speeding up generic operations */ /* Circular rotate of 32 bit values */ #define rotr(x,n) (((x) >> ((int)(n))) | ((x) << (32 - (int)(n)))) #define rotl(x,n) (((x) << ((int)(n))) | ((x) >> (32 - (int)(n)))) /* Invert byte order in a 32 bit variable */ #define bswap(x) ((rotl(x, 8) & 0x00ff00ff) | (rotr(x, 8) & 0xff00ff00)) /* Extract byte from a 32 bit quantity (little endian notation) */ #define byte(x,n) ((u1byte)((x) >> (8 * n))) #if BYTE_ORDER != LITTLE_ENDIAN #define BYTE_SWAP #endif #ifdef BYTE_SWAP #define io_swap(x) bswap(x) #else #define io_swap(x) (x) #endif #define LARGE_TABLES 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 */ /* 0x11b as modular polynomial - the simplest prmitive */ /* root is 0x11, 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); } /* note that the affine byte transformation matrix in */ /* rijndael specification is in big endian format with */ /* bit 0 as the most significant bit. In the remainder */ /* of the specification the bits are numbered from the */ /* least significant end of a byte. */ 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] = (u1byte)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) /* 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; \ } rijndael_ctx * rijndael_set_key(rijndael_ctx *ctx, const u4byte *in_key, const u4byte key_len, int encrypt) { u4byte i, t, u, v, w; u4byte *e_key = ctx->e_key; u4byte *d_key = ctx->d_key; ctx->decrypt = !encrypt; if(!tab_gen) gen_tabs(); ctx->k_len = (key_len + 31) / 32; e_key[0] = io_swap(in_key[0]); e_key[1] = io_swap(in_key[1]); e_key[2] = io_swap(in_key[2]); e_key[3] = io_swap(in_key[3]); switch(ctx->k_len) { case 4: t = e_key[3]; for(i = 0; i < 10; ++i) loop4(i); break; case 6: e_key[4] = io_swap(in_key[4]); t = e_key[5] = io_swap(in_key[5]); for(i = 0; i < 8; ++i) loop6(i); break; case 8: e_key[4] = io_swap(in_key[4]); e_key[5] = io_swap(in_key[5]); e_key[6] = io_swap(in_key[6]); t = e_key[7] = io_swap(in_key[7]); for(i = 0; i < 7; ++i) loop8(i); break; } if (!encrypt) { d_key[0] = e_key[0]; d_key[1] = e_key[1]; d_key[2] = e_key[2]; d_key[3] = e_key[3]; for(i = 4; i < 4 * ctx->k_len + 24; ++i) { imix_col(d_key[i], e_key[i]); } } return ctx; } /* encrypt a block of text */ #define f_nround(bo, bi, k) \ f_rn(bo, bi, 0, k); \ f_rn(bo, bi, 1, k); \ f_rn(bo, bi, 2, k); \ f_rn(bo, bi, 3, k); \ k += 4 #define f_lround(bo, bi, k) \ f_rl(bo, bi, 0, k); \ f_rl(bo, bi, 1, k); \ f_rl(bo, bi, 2, k); \ f_rl(bo, bi, 3, k) void rijndael_encrypt(rijndael_ctx *ctx, const u4byte *in_blk, u4byte *out_blk) { u4byte k_len = ctx->k_len; u4byte *e_key = ctx->e_key; u4byte b0[4], b1[4], *kp; b0[0] = io_swap(in_blk[0]) ^ e_key[0]; b0[1] = io_swap(in_blk[1]) ^ e_key[1]; b0[2] = io_swap(in_blk[2]) ^ e_key[2]; b0[3] = io_swap(in_blk[3]) ^ e_key[3]; kp = e_key + 4; if(k_len > 6) { f_nround(b1, b0, kp); f_nround(b0, b1, kp); } if(k_len > 4) { f_nround(b1, b0, kp); f_nround(b0, b1, kp); } f_nround(b1, b0, kp); f_nround(b0, b1, kp); f_nround(b1, b0, kp); f_nround(b0, b1, kp); f_nround(b1, b0, kp); f_nround(b0, b1, kp); f_nround(b1, b0, kp); f_nround(b0, b1, kp); f_nround(b1, b0, kp); f_lround(b0, b1, kp); out_blk[0] = io_swap(b0[0]); out_blk[1] = io_swap(b0[1]); out_blk[2] = io_swap(b0[2]); out_blk[3] = io_swap(b0[3]); } /* decrypt a block of text */ #define i_nround(bo, bi, k) \ i_rn(bo, bi, 0, k); \ i_rn(bo, bi, 1, k); \ i_rn(bo, bi, 2, k); \ i_rn(bo, bi, 3, k); \ k -= 4 #define i_lround(bo, bi, k) \ i_rl(bo, bi, 0, k); \ i_rl(bo, bi, 1, k); \ i_rl(bo, bi, 2, k); \ i_rl(bo, bi, 3, k) void rijndael_decrypt(rijndael_ctx *ctx, const u4byte *in_blk, u4byte *out_blk) { u4byte b0[4], b1[4], *kp; u4byte k_len = ctx->k_len; u4byte *e_key = ctx->e_key; u4byte *d_key = ctx->d_key; b0[0] = io_swap(in_blk[0]) ^ e_key[4 * k_len + 24]; b0[1] = io_swap(in_blk[1]) ^ e_key[4 * k_len + 25]; b0[2] = io_swap(in_blk[2]) ^ e_key[4 * k_len + 26]; b0[3] = io_swap(in_blk[3]) ^ e_key[4 * k_len + 27]; kp = d_key + 4 * (k_len + 5); if(k_len > 6) { i_nround(b1, b0, kp); i_nround(b0, b1, kp); } if(k_len > 4) { i_nround(b1, b0, kp); i_nround(b0, b1, kp); } i_nround(b1, b0, kp); i_nround(b0, b1, kp); i_nround(b1, b0, kp); i_nround(b0, b1, kp); i_nround(b1, b0, kp); i_nround(b0, b1, kp); i_nround(b1, b0, kp); i_nround(b0, b1, kp); i_nround(b1, b0, kp); i_lround(b0, b1, kp); out_blk[0] = io_swap(b0[0]); out_blk[1] = io_swap(b0[1]); out_blk[2] = io_swap(b0[2]); out_blk[3] = io_swap(b0[3]); }