Annotation of src/usr.bin/ssh/rijndael.c, Revision 1.2.2.1
1.2.2.1 ! jason 1: /* $OpenBSD: rijndael.c,v 1.7 2001/02/04 15:32:24 stevesk Exp $ */
1.1 markus 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: /* */
10: /* Copyright in this implementation is held by Dr B R Gladman but I */
11: /* hereby give permission for its free direct or derivative use subject */
12: /* to acknowledgment of its origin and compliance with any conditions */
13: /* that the originators of the algorithm place on its exploitation. */
14: /* */
15: /* Dr Brian Gladman (gladman@seven77.demon.co.uk) 14th January 1999 */
16:
17: /* Timing data for Rijndael (rijndael.c)
18:
19: Algorithm: rijndael (rijndael.c)
20:
21: 128 bit key:
22: Key Setup: 305/1389 cycles (encrypt/decrypt)
23: Encrypt: 374 cycles = 68.4 mbits/sec
24: Decrypt: 352 cycles = 72.7 mbits/sec
25: Mean: 363 cycles = 70.5 mbits/sec
26:
27: 192 bit key:
28: Key Setup: 277/1595 cycles (encrypt/decrypt)
29: Encrypt: 439 cycles = 58.3 mbits/sec
30: Decrypt: 425 cycles = 60.2 mbits/sec
31: Mean: 432 cycles = 59.3 mbits/sec
32:
33: 256 bit key:
34: Key Setup: 374/1960 cycles (encrypt/decrypt)
35: Encrypt: 502 cycles = 51.0 mbits/sec
36: Decrypt: 498 cycles = 51.4 mbits/sec
37: Mean: 500 cycles = 51.2 mbits/sec
38:
39: */
40:
41: #include <sys/types.h>
42: #include "rijndael.h"
43:
44: void gen_tabs __P((void));
45:
46: /* 3. Basic macros for speeding up generic operations */
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:
1.2.2.1 ! jason 55: #define bswap(x) ((rotl(x, 8) & 0x00ff00ff) | (rotr(x, 8) & 0xff00ff00))
1.1 markus 56:
1.2.2.1 ! jason 57: /* Extract byte from a 32 bit quantity (little endian notation) */
1.1 markus 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:
73: u1byte pow_tab[256];
74: u1byte log_tab[256];
75: u1byte sbx_tab[256];
76: u1byte isb_tab[256];
77: u4byte rco_tab[ 10];
78: u4byte ft_tab[4][256];
79: u4byte it_tab[4][256];
80:
81: #ifdef LARGE_TABLES
82: u4byte fl_tab[4][256];
83: u4byte il_tab[4][256];
84: #endif
85:
86: u4byte 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)] ^ \
1.2.2.1 ! jason 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)
1.1 markus 95:
96: #define i_rn(bo, bi, n, k) \
97: bo[n] = it_tab[0][byte(bi[n],0)] ^ \
1.2.2.1 ! jason 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)
1.1 markus 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)] ^ \
1.2.2.1 ! jason 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)
1.1 markus 115:
116: #define i_rl(bo, bi, n, k) \
117: bo[n] = il_tab[0][byte(bi[n],0)] ^ \
1.2.2.1 ! jason 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)
1.1 markus 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)] ^ \
1.2.2.1 ! jason 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)
1.1 markus 135:
136: #define i_rl(bo, bi, n, k) \
137: bo[n] = (u4byte)isb_tab[byte(bi[n],0)] ^ \
1.2.2.1 ! jason 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)
1.1 markus 141:
142: #endif
143:
144: void
145: gen_tabs(void)
146: {
147: u4byte i, t;
148: u1byte p, q;
149:
150: /* log and power tables for GF(2**8) finite field with */
151: /* 0x11b as modular polynomial - the simplest prmitive */
152: /* root is 0x11, used here to generate the tables */
153:
154: for(i = 0,p = 1; i < 256; ++i) {
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) {
1.2.2.1 ! jason 163: rco_tab[i] = p;
1.1 markus 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) {
1.2.2.1 ! jason 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;
1.1 markus 180: sbx_tab[i] = (u1byte)p; isb_tab[p] = (u1byte)i;
181: }
182:
183: for(i = 0; i < 256; ++i) {
1.2.2.1 ! jason 184: p = sbx_tab[i];
! 185:
! 186: #ifdef LARGE_TABLES
1.1 markus 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);
1.2.2.1 ! jason 197:
1.1 markus 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:
1.2.2.1 ! jason 203: p = isb_tab[i];
1.1 markus 204:
1.2.2.1 ! jason 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);
1.1 markus 210: il_tab[3][i] = rotl(t, 24);
1.2.2.1 ! jason 211: #endif
1.1 markus 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);
1.2.2.1 ! jason 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);
1.1 markus 221: }
222:
223: tab_gen = 1;
1.2 markus 224: }
1.1 markus 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) ^ \
1.2.2.1 ! jason 235: rotr(v ^ t, 16) ^ \
! 236: rotr(t,24)
1.1 markus 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; \
245: t ^= e_key[4 * i + 3]; e_key[4 * i + 7] = t; \
246: }
247:
248: #define loop6(i) \
249: { t = ls_box(rotr(t, 8)) ^ rco_tab[i]; \
250: t ^= e_key[6 * i]; e_key[6 * i + 6] = t; \
251: t ^= e_key[6 * i + 1]; e_key[6 * i + 7] = t; \
252: t ^= e_key[6 * i + 2]; e_key[6 * i + 8] = t; \
253: t ^= e_key[6 * i + 3]; e_key[6 * i + 9] = t; \
254: t ^= e_key[6 * i + 4]; e_key[6 * i + 10] = t; \
255: t ^= e_key[6 * i + 5]; e_key[6 * i + 11] = t; \
256: }
257:
258: #define loop8(i) \
259: { t = ls_box(rotr(t, 8)) ^ rco_tab[i]; \
260: t ^= e_key[8 * i]; e_key[8 * i + 8] = t; \
261: t ^= e_key[8 * i + 1]; e_key[8 * i + 9] = t; \
262: t ^= e_key[8 * i + 2]; e_key[8 * i + 10] = t; \
263: t ^= e_key[8 * i + 3]; e_key[8 * i + 11] = t; \
264: t = e_key[8 * i + 4] ^ ls_box(t); \
265: e_key[8 * i + 12] = t; \
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:
271: rijndael_ctx *
272: rijndael_set_key(rijndael_ctx *ctx, const u4byte *in_key, const u4byte key_len,
273: int encrypt)
1.2.2.1 ! jason 274: {
1.1 markus 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:
1.2.2.1 ! jason 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:
1.1 markus 289: switch(ctx->k_len) {
1.2.2.1 ! jason 290: case 4: t = e_key[3];
! 291: for(i = 0; i < 10; ++i)
1.1 markus 292: loop4(i);
1.2.2.1 ! jason 293: break;
1.1 markus 294:
1.2.2.1 ! jason 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)
1.1 markus 297: loop6(i);
1.2.2.1 ! jason 298: break;
1.1 markus 299:
1.2.2.1 ! jason 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)
1.1 markus 303: loop8(i);
1.2.2.1 ! jason 304: break;
1.1 markus 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]);
313: }
314: }
315:
316: return ctx;
1.2 markus 317: }
1.1 markus 318:
319: /* encrypt a block of text */
320:
321: #define f_nround(bo, bi, k) \
322: f_rn(bo, bi, 0, k); \
323: f_rn(bo, bi, 1, k); \
324: f_rn(bo, bi, 2, k); \
325: f_rn(bo, bi, 3, k); \
326: k += 4
327:
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:
334: void
335: rijndael_encrypt(rijndael_ctx *ctx, const u4byte *in_blk, u4byte *out_blk)
1.2.2.1 ! jason 336: {
1.1 markus 337: u4byte k_len = ctx->k_len;
338: u4byte *e_key = ctx->e_key;
339: u4byte b0[4], b1[4], *kp;
340:
1.2.2.1 ! jason 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];
1.1 markus 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:
1.2.2.1 ! jason 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]);
1.2 markus 364: }
1.1 markus 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:
381: void
382: rijndael_decrypt(rijndael_ctx *ctx, const u4byte *in_blk, u4byte *out_blk)
1.2.2.1 ! jason 383: {
1.1 markus 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:
1.2.2.1 ! jason 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];
1.1 markus 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:
1.2.2.1 ! jason 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]);
1.2 markus 412: }