diff options
Diffstat (limited to 'src/lib/libcrypto/bn/bn_exp2.c')
-rw-r--r-- | src/lib/libcrypto/bn/bn_exp2.c | 252 |
1 files changed, 122 insertions, 130 deletions
diff --git a/src/lib/libcrypto/bn/bn_exp2.c b/src/lib/libcrypto/bn/bn_exp2.c index bd0c34b91b..d3d3d978bd 100644 --- a/src/lib/libcrypto/bn/bn_exp2.c +++ b/src/lib/libcrypto/bn/bn_exp2.c | |||
@@ -5,21 +5,21 @@ | |||
5 | * This package is an SSL implementation written | 5 | * This package is an SSL implementation written |
6 | * by Eric Young (eay@cryptsoft.com). | 6 | * by Eric Young (eay@cryptsoft.com). |
7 | * The implementation was written so as to conform with Netscapes SSL. | 7 | * The implementation was written so as to conform with Netscapes SSL. |
8 | * | 8 | * |
9 | * This library is free for commercial and non-commercial use as long as | 9 | * This library is free for commercial and non-commercial use as long as |
10 | * the following conditions are aheared to. The following conditions | 10 | * the following conditions are aheared to. The following conditions |
11 | * apply to all code found in this distribution, be it the RC4, RSA, | 11 | * apply to all code found in this distribution, be it the RC4, RSA, |
12 | * lhash, DES, etc., code; not just the SSL code. The SSL documentation | 12 | * lhash, DES, etc., code; not just the SSL code. The SSL documentation |
13 | * included with this distribution is covered by the same copyright terms | 13 | * included with this distribution is covered by the same copyright terms |
14 | * except that the holder is Tim Hudson (tjh@cryptsoft.com). | 14 | * except that the holder is Tim Hudson (tjh@cryptsoft.com). |
15 | * | 15 | * |
16 | * Copyright remains Eric Young's, and as such any Copyright notices in | 16 | * Copyright remains Eric Young's, and as such any Copyright notices in |
17 | * the code are not to be removed. | 17 | * the code are not to be removed. |
18 | * If this package is used in a product, Eric Young should be given attribution | 18 | * If this package is used in a product, Eric Young should be given attribution |
19 | * as the author of the parts of the library used. | 19 | * as the author of the parts of the library used. |
20 | * This can be in the form of a textual message at program startup or | 20 | * This can be in the form of a textual message at program startup or |
21 | * in documentation (online or textual) provided with the package. | 21 | * in documentation (online or textual) provided with the package. |
22 | * | 22 | * |
23 | * Redistribution and use in source and binary forms, with or without | 23 | * Redistribution and use in source and binary forms, with or without |
24 | * modification, are permitted provided that the following conditions | 24 | * modification, are permitted provided that the following conditions |
25 | * are met: | 25 | * are met: |
@@ -34,10 +34,10 @@ | |||
34 | * Eric Young (eay@cryptsoft.com)" | 34 | * Eric Young (eay@cryptsoft.com)" |
35 | * The word 'cryptographic' can be left out if the rouines from the library | 35 | * The word 'cryptographic' can be left out if the rouines from the library |
36 | * being used are not cryptographic related :-). | 36 | * being used are not cryptographic related :-). |
37 | * 4. If you include any Windows specific code (or a derivative thereof) from | 37 | * 4. If you include any Windows specific code (or a derivative thereof) from |
38 | * the apps directory (application code) you must include an acknowledgement: | 38 | * the apps directory (application code) you must include an acknowledgement: |
39 | * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" | 39 | * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" |
40 | * | 40 | * |
41 | * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND | 41 | * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND |
42 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | 42 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
43 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | 43 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
@@ -49,7 +49,7 @@ | |||
49 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | 49 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
50 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | 50 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
51 | * SUCH DAMAGE. | 51 | * SUCH DAMAGE. |
52 | * | 52 | * |
53 | * The licence and distribution terms for any publically available version or | 53 | * The licence and distribution terms for any publically available version or |
54 | * derivative of this code cannot be changed. i.e. this code cannot simply be | 54 | * derivative of this code cannot be changed. i.e. this code cannot simply be |
55 | * copied and put under another distribution licence | 55 | * copied and put under another distribution licence |
@@ -63,7 +63,7 @@ | |||
63 | * are met: | 63 | * are met: |
64 | * | 64 | * |
65 | * 1. Redistributions of source code must retain the above copyright | 65 | * 1. Redistributions of source code must retain the above copyright |
66 | * notice, this list of conditions and the following disclaimer. | 66 | * notice, this list of conditions and the following disclaimer. |
67 | * | 67 | * |
68 | * 2. Redistributions in binary form must reproduce the above copyright | 68 | * 2. Redistributions in binary form must reproduce the above copyright |
69 | * notice, this list of conditions and the following disclaimer in | 69 | * notice, this list of conditions and the following disclaimer in |
@@ -115,17 +115,18 @@ | |||
115 | 115 | ||
116 | #define TABLE_SIZE 32 | 116 | #define TABLE_SIZE 32 |
117 | 117 | ||
118 | int BN_mod_exp2_mont(BIGNUM *rr, const BIGNUM *a1, const BIGNUM *p1, | 118 | int |
119 | const BIGNUM *a2, const BIGNUM *p2, const BIGNUM *m, | 119 | BN_mod_exp2_mont(BIGNUM *rr, const BIGNUM *a1, const BIGNUM *p1, |
120 | BN_CTX *ctx, BN_MONT_CTX *in_mont) | 120 | const BIGNUM *a2, const BIGNUM *p2, const BIGNUM *m, BN_CTX *ctx, |
121 | { | 121 | BN_MONT_CTX *in_mont) |
122 | int i,j,bits,b,bits1,bits2,ret=0,wpos1,wpos2,window1,window2,wvalue1,wvalue2; | 122 | { |
123 | int r_is_one=1; | 123 | int i, j, bits, b, bits1, bits2, ret = 0, wpos1, wpos2, window1, window2, wvalue1, wvalue2; |
124 | BIGNUM *d,*r; | 124 | int r_is_one = 1; |
125 | BIGNUM *d, *r; | ||
125 | const BIGNUM *a_mod_m; | 126 | const BIGNUM *a_mod_m; |
126 | /* Tables of variables obtained from 'ctx' */ | 127 | /* Tables of variables obtained from 'ctx' */ |
127 | BIGNUM *val1[TABLE_SIZE], *val2[TABLE_SIZE]; | 128 | BIGNUM *val1[TABLE_SIZE], *val2[TABLE_SIZE]; |
128 | BN_MONT_CTX *mont=NULL; | 129 | BN_MONT_CTX *mont = NULL; |
129 | 130 | ||
130 | bn_check_top(a1); | 131 | bn_check_top(a1); |
131 | bn_check_top(p1); | 132 | bn_check_top(p1); |
@@ -133,35 +134,35 @@ int BN_mod_exp2_mont(BIGNUM *rr, const BIGNUM *a1, const BIGNUM *p1, | |||
133 | bn_check_top(p2); | 134 | bn_check_top(p2); |
134 | bn_check_top(m); | 135 | bn_check_top(m); |
135 | 136 | ||
136 | if (!(m->d[0] & 1)) | 137 | if (!(m->d[0] & 1)) { |
137 | { | 138 | BNerr(BN_F_BN_MOD_EXP2_MONT, BN_R_CALLED_WITH_EVEN_MODULUS); |
138 | BNerr(BN_F_BN_MOD_EXP2_MONT,BN_R_CALLED_WITH_EVEN_MODULUS); | 139 | return (0); |
139 | return(0); | 140 | } |
140 | } | 141 | bits1 = BN_num_bits(p1); |
141 | bits1=BN_num_bits(p1); | 142 | bits2 = BN_num_bits(p2); |
142 | bits2=BN_num_bits(p2); | 143 | if ((bits1 == 0) && (bits2 == 0)) { |
143 | if ((bits1 == 0) && (bits2 == 0)) | ||
144 | { | ||
145 | ret = BN_one(rr); | 144 | ret = BN_one(rr); |
146 | return ret; | 145 | return ret; |
147 | } | 146 | } |
148 | 147 | ||
149 | bits=(bits1 > bits2)?bits1:bits2; | 148 | bits = (bits1 > bits2) ? bits1 : bits2; |
150 | 149 | ||
151 | BN_CTX_start(ctx); | 150 | BN_CTX_start(ctx); |
152 | d = BN_CTX_get(ctx); | 151 | d = BN_CTX_get(ctx); |
153 | r = BN_CTX_get(ctx); | 152 | r = BN_CTX_get(ctx); |
154 | val1[0] = BN_CTX_get(ctx); | 153 | val1[0] = BN_CTX_get(ctx); |
155 | val2[0] = BN_CTX_get(ctx); | 154 | val2[0] = BN_CTX_get(ctx); |
156 | if(!d || !r || !val1[0] || !val2[0]) goto err; | 155 | if (!d || !r || !val1[0] || !val2[0]) |
156 | goto err; | ||
157 | 157 | ||
158 | if (in_mont != NULL) | 158 | if (in_mont != NULL) |
159 | mont=in_mont; | 159 | mont = in_mont; |
160 | else | 160 | else { |
161 | { | 161 | if ((mont = BN_MONT_CTX_new()) == NULL) |
162 | if ((mont=BN_MONT_CTX_new()) == NULL) goto err; | 162 | goto err; |
163 | if (!BN_MONT_CTX_set(mont,m,ctx)) goto err; | 163 | if (!BN_MONT_CTX_set(mont, m, ctx)) |
164 | } | 164 | goto err; |
165 | } | ||
165 | 166 | ||
166 | window1 = BN_window_bits_for_exponent_size(bits1); | 167 | window1 = BN_window_bits_for_exponent_size(bits1); |
167 | window2 = BN_window_bits_for_exponent_size(bits2); | 168 | window2 = BN_window_bits_for_exponent_size(bits2); |
@@ -169,144 +170,135 @@ int BN_mod_exp2_mont(BIGNUM *rr, const BIGNUM *a1, const BIGNUM *p1, | |||
169 | /* | 170 | /* |
170 | * Build table for a1: val1[i] := a1^(2*i + 1) mod m for i = 0 .. 2^(window1-1) | 171 | * Build table for a1: val1[i] := a1^(2*i + 1) mod m for i = 0 .. 2^(window1-1) |
171 | */ | 172 | */ |
172 | if (a1->neg || BN_ucmp(a1,m) >= 0) | 173 | if (a1->neg || BN_ucmp(a1, m) >= 0) { |
173 | { | 174 | if (!BN_mod(val1[0], a1, m, ctx)) |
174 | if (!BN_mod(val1[0],a1,m,ctx)) | ||
175 | goto err; | 175 | goto err; |
176 | a_mod_m = val1[0]; | 176 | a_mod_m = val1[0]; |
177 | } | 177 | } else |
178 | else | ||
179 | a_mod_m = a1; | 178 | a_mod_m = a1; |
180 | if (BN_is_zero(a_mod_m)) | 179 | if (BN_is_zero(a_mod_m)) { |
181 | { | ||
182 | BN_zero(rr); | 180 | BN_zero(rr); |
183 | ret = 1; | 181 | ret = 1; |
184 | goto err; | 182 | goto err; |
185 | } | 183 | } |
186 | 184 | ||
187 | if (!BN_to_montgomery(val1[0],a_mod_m,mont,ctx)) goto err; | 185 | if (!BN_to_montgomery(val1[0], a_mod_m, mont, ctx)) |
188 | if (window1 > 1) | 186 | goto err; |
189 | { | 187 | if (window1 > 1) { |
190 | if (!BN_mod_mul_montgomery(d,val1[0],val1[0],mont,ctx)) goto err; | 188 | if (!BN_mod_mul_montgomery(d, val1[0], val1[0], mont, ctx)) |
189 | goto err; | ||
191 | 190 | ||
192 | j=1<<(window1-1); | 191 | j = 1 << (window1 - 1); |
193 | for (i=1; i<j; i++) | 192 | for (i = 1; i < j; i++) { |
194 | { | 193 | if (((val1[i] = BN_CTX_get(ctx)) == NULL) || |
195 | if(((val1[i] = BN_CTX_get(ctx)) == NULL) || | 194 | !BN_mod_mul_montgomery(val1[i], val1[i - 1], |
196 | !BN_mod_mul_montgomery(val1[i],val1[i-1], | 195 | d, mont, ctx)) |
197 | d,mont,ctx)) | ||
198 | goto err; | 196 | goto err; |
199 | } | ||
200 | } | 197 | } |
198 | } | ||
201 | 199 | ||
202 | 200 | ||
203 | /* | 201 | /* |
204 | * Build table for a2: val2[i] := a2^(2*i + 1) mod m for i = 0 .. 2^(window2-1) | 202 | * Build table for a2: val2[i] := a2^(2*i + 1) mod m for i = 0 .. 2^(window2-1) |
205 | */ | 203 | */ |
206 | if (a2->neg || BN_ucmp(a2,m) >= 0) | 204 | if (a2->neg || BN_ucmp(a2, m) >= 0) { |
207 | { | 205 | if (!BN_mod(val2[0], a2, m, ctx)) |
208 | if (!BN_mod(val2[0],a2,m,ctx)) | ||
209 | goto err; | 206 | goto err; |
210 | a_mod_m = val2[0]; | 207 | a_mod_m = val2[0]; |
211 | } | 208 | } else |
212 | else | ||
213 | a_mod_m = a2; | 209 | a_mod_m = a2; |
214 | if (BN_is_zero(a_mod_m)) | 210 | if (BN_is_zero(a_mod_m)) { |
215 | { | ||
216 | BN_zero(rr); | 211 | BN_zero(rr); |
217 | ret = 1; | 212 | ret = 1; |
218 | goto err; | 213 | goto err; |
219 | } | 214 | } |
220 | if (!BN_to_montgomery(val2[0],a_mod_m,mont,ctx)) goto err; | 215 | if (!BN_to_montgomery(val2[0], a_mod_m, mont, ctx)) |
221 | if (window2 > 1) | 216 | goto err; |
222 | { | 217 | if (window2 > 1) { |
223 | if (!BN_mod_mul_montgomery(d,val2[0],val2[0],mont,ctx)) goto err; | 218 | if (!BN_mod_mul_montgomery(d, val2[0], val2[0], mont, ctx)) |
219 | goto err; | ||
224 | 220 | ||
225 | j=1<<(window2-1); | 221 | j = 1 << (window2 - 1); |
226 | for (i=1; i<j; i++) | 222 | for (i = 1; i < j; i++) { |
227 | { | 223 | if (((val2[i] = BN_CTX_get(ctx)) == NULL) || |
228 | if(((val2[i] = BN_CTX_get(ctx)) == NULL) || | 224 | !BN_mod_mul_montgomery(val2[i], val2[i - 1], |
229 | !BN_mod_mul_montgomery(val2[i],val2[i-1], | 225 | d, mont, ctx)) |
230 | d,mont,ctx)) | ||
231 | goto err; | 226 | goto err; |
232 | } | ||
233 | } | 227 | } |
228 | } | ||
234 | 229 | ||
235 | 230 | ||
236 | /* Now compute the power product, using independent windows. */ | 231 | /* Now compute the power product, using independent windows. */ |
237 | r_is_one=1; | 232 | r_is_one = 1; |
238 | wvalue1=0; /* The 'value' of the first window */ | 233 | wvalue1 = 0; /* The 'value' of the first window */ |
239 | wvalue2=0; /* The 'value' of the second window */ | 234 | wvalue2 = 0; /* The 'value' of the second window */ |
240 | wpos1=0; /* If wvalue1 > 0, the bottom bit of the first window */ | 235 | wpos1 = 0; /* If wvalue1 > 0, the bottom bit of the first window */ |
241 | wpos2=0; /* If wvalue2 > 0, the bottom bit of the second window */ | 236 | wpos2 = 0; /* If wvalue2 > 0, the bottom bit of the second window */ |
242 | 237 | ||
243 | if (!BN_to_montgomery(r,BN_value_one(),mont,ctx)) goto err; | 238 | if (!BN_to_montgomery(r, BN_value_one(), mont, ctx)) |
244 | for (b=bits-1; b>=0; b--) | 239 | goto err; |
245 | { | 240 | for (b = bits - 1; b >= 0; b--) { |
246 | if (!r_is_one) | 241 | if (!r_is_one) { |
247 | { | 242 | if (!BN_mod_mul_montgomery(r, r,r, mont, ctx)) |
248 | if (!BN_mod_mul_montgomery(r,r,r,mont,ctx)) | ||
249 | goto err; | 243 | goto err; |
250 | } | 244 | } |
251 | 245 | ||
252 | if (!wvalue1) | 246 | if (!wvalue1) |
253 | if (BN_is_bit_set(p1, b)) | 247 | if (BN_is_bit_set(p1, b)) { |
254 | { | 248 | /* consider bits b-window1+1 .. b for this window */ |
255 | /* consider bits b-window1+1 .. b for this window */ | 249 | i = b - window1 + 1; |
256 | i = b-window1+1; | 250 | while (!BN_is_bit_set(p1, i)) /* works for i<0 */ |
257 | while (!BN_is_bit_set(p1, i)) /* works for i<0 */ | 251 | i++; |
258 | i++; | 252 | wpos1 = i; |
259 | wpos1 = i; | 253 | wvalue1 = 1; |
260 | wvalue1 = 1; | 254 | for (i = b - 1; i >= wpos1; i--) { |
261 | for (i = b-1; i >= wpos1; i--) | 255 | wvalue1 <<= 1; |
262 | { | 256 | if (BN_is_bit_set(p1, i)) |
263 | wvalue1 <<= 1; | 257 | wvalue1++; |
264 | if (BN_is_bit_set(p1, i)) | 258 | } |
265 | wvalue1++; | 259 | } |
266 | } | 260 | |
267 | } | ||
268 | |||
269 | if (!wvalue2) | 261 | if (!wvalue2) |
270 | if (BN_is_bit_set(p2, b)) | 262 | if (BN_is_bit_set(p2, b)) { |
271 | { | 263 | /* consider bits b-window2+1 .. b for this window */ |
272 | /* consider bits b-window2+1 .. b for this window */ | 264 | i = b - window2 + 1; |
273 | i = b-window2+1; | 265 | while (!BN_is_bit_set(p2, i)) |
274 | while (!BN_is_bit_set(p2, i)) | 266 | i++; |
275 | i++; | 267 | wpos2 = i; |
276 | wpos2 = i; | 268 | wvalue2 = 1; |
277 | wvalue2 = 1; | 269 | for (i = b - 1; i >= wpos2; i--) { |
278 | for (i = b-1; i >= wpos2; i--) | 270 | wvalue2 <<= 1; |
279 | { | 271 | if (BN_is_bit_set(p2, i)) |
280 | wvalue2 <<= 1; | 272 | wvalue2++; |
281 | if (BN_is_bit_set(p2, i)) | 273 | } |
282 | wvalue2++; | 274 | } |
283 | } | ||
284 | } | ||
285 | 275 | ||
286 | if (wvalue1 && b == wpos1) | 276 | if (wvalue1 && b == wpos1) { |
287 | { | ||
288 | /* wvalue1 is odd and < 2^window1 */ | 277 | /* wvalue1 is odd and < 2^window1 */ |
289 | if (!BN_mod_mul_montgomery(r,r,val1[wvalue1>>1],mont,ctx)) | 278 | if (!BN_mod_mul_montgomery(r, r, val1[wvalue1 >> 1], |
279 | mont, ctx)) | ||
290 | goto err; | 280 | goto err; |
291 | wvalue1 = 0; | 281 | wvalue1 = 0; |
292 | r_is_one = 0; | 282 | r_is_one = 0; |
293 | } | 283 | } |
294 | 284 | ||
295 | if (wvalue2 && b == wpos2) | 285 | if (wvalue2 && b == wpos2) { |
296 | { | ||
297 | /* wvalue2 is odd and < 2^window2 */ | 286 | /* wvalue2 is odd and < 2^window2 */ |
298 | if (!BN_mod_mul_montgomery(r,r,val2[wvalue2>>1],mont,ctx)) | 287 | if (!BN_mod_mul_montgomery(r, r, val2[wvalue2 >> 1], |
288 | mont, ctx)) | ||
299 | goto err; | 289 | goto err; |
300 | wvalue2 = 0; | 290 | wvalue2 = 0; |
301 | r_is_one = 0; | 291 | r_is_one = 0; |
302 | } | ||
303 | } | 292 | } |
304 | if (!BN_from_montgomery(rr,r,mont,ctx)) | 293 | } |
294 | if (!BN_from_montgomery(rr, r,mont, ctx)) | ||
305 | goto err; | 295 | goto err; |
306 | ret=1; | 296 | ret = 1; |
297 | |||
307 | err: | 298 | err: |
308 | if ((in_mont == NULL) && (mont != NULL)) BN_MONT_CTX_free(mont); | 299 | if ((in_mont == NULL) && (mont != NULL)) |
300 | BN_MONT_CTX_free(mont); | ||
309 | BN_CTX_end(ctx); | 301 | BN_CTX_end(ctx); |
310 | bn_check_top(rr); | 302 | bn_check_top(rr); |
311 | return(ret); | 303 | return (ret); |
312 | } | 304 | } |