xref: /illumos-gate/usr/src/common/crypto/ecc/ec2_193.c (revision 55fea89dcaa64928bed4327112404dcb3e07b79f)
1 /*
2  * ***** BEGIN LICENSE BLOCK *****
3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
4  *
5  * The contents of this file are subject to the Mozilla Public License Version
6  * 1.1 (the "License"); you may not use this file except in compliance with
7  * the License. You may obtain a copy of the License at
8  * http://www.mozilla.org/MPL/
9  *
10  * Software distributed under the License is distributed on an "AS IS" basis,
11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
12  * for the specific language governing rights and limitations under the
13  * License.
14  *
15  * The Original Code is the elliptic curve math library for binary polynomial field curves.
16  *
17  * The Initial Developer of the Original Code is
18  * Sun Microsystems, Inc.
19  * Portions created by the Initial Developer are Copyright (C) 2003
20  * the Initial Developer. All Rights Reserved.
21  *
22  * Contributor(s):
23  *   Sheueling Chang-Shantz <sheueling.chang@sun.com>,
24  *   Stephen Fung <fungstep@hotmail.com>, and
25  *   Douglas Stebila <douglas@stebila.ca>, Sun Microsystems Laboratories.
26  *
27  * Alternatively, the contents of this file may be used under the terms of
28  * either the GNU General Public License Version 2 or later (the "GPL"), or
29  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
30  * in which case the provisions of the GPL or the LGPL are applicable instead
31  * of those above. If you wish to allow use of your version of this file only
32  * under the terms of either the GPL or the LGPL, and not to allow others to
33  * use your version of this file under the terms of the MPL, indicate your
34  * decision by deleting the provisions above and replace them with the notice
35  * and other provisions required by the GPL or the LGPL. If you do not delete
36  * the provisions above, a recipient may use your version of this file under
37  * the terms of any one of the MPL, the GPL or the LGPL.
38  *
39  * ***** END LICENSE BLOCK ***** */
40 /*
41  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
42  * Use is subject to license terms.
43  *
44  * Sun elects to use this software under the MPL license.
45  */
46 
47 #include "ec2.h"
48 #include "mp_gf2m.h"
49 #include "mp_gf2m-priv.h"
50 #include "mpi.h"
51 #include "mpi-priv.h"
52 #ifndef _KERNEL
53 #include <stdlib.h>
54 #endif
55 
56 /* Fast reduction for polynomials over a 193-bit curve. Assumes reduction
57  * polynomial with terms {193, 15, 0}. */
58 mp_err
ec_GF2m_193_mod(const mp_int * a,mp_int * r,const GFMethod * meth)59 ec_GF2m_193_mod(const mp_int *a, mp_int *r, const GFMethod *meth)
60 {
61 	mp_err res = MP_OKAY;
62 	mp_digit *u, z;
63 
64 	if (a != r) {
65 		MP_CHECKOK(mp_copy(a, r));
66 	}
67 #ifdef ECL_SIXTY_FOUR_BIT
68 	if (MP_USED(r) < 7) {
69 		MP_CHECKOK(s_mp_pad(r, 7));
70 	}
71 	u = MP_DIGITS(r);
72 	MP_USED(r) = 7;
73 
74 	/* u[6] only has 2 significant bits */
75 	z = u[6];
76 	u[3] ^= (z << 14) ^ (z >> 1);
77 	u[2] ^= (z << 63);
78 	z = u[5];
79 	u[3] ^= (z >> 50);
80 	u[2] ^= (z << 14) ^ (z >> 1);
81 	u[1] ^= (z << 63);
82 	z = u[4];
83 	u[2] ^= (z >> 50);
84 	u[1] ^= (z << 14) ^ (z >> 1);
85 	u[0] ^= (z << 63);
86 	z = u[3] >> 1;				/* z only has 63 significant bits */
87 	u[1] ^= (z >> 49);
88 	u[0] ^= (z << 15) ^ z;
89 	/* clear bits above 193 */
90 	u[6] = u[5] = u[4] = 0;
91 	u[3] ^= z << 1;
92 #else
93 	if (MP_USED(r) < 13) {
94 		MP_CHECKOK(s_mp_pad(r, 13));
95 	}
96 	u = MP_DIGITS(r);
97 	MP_USED(r) = 13;
98 
99 	/* u[12] only has 2 significant bits */
100 	z = u[12];
101 	u[6] ^= (z << 14) ^ (z >> 1);
102 	u[5] ^= (z << 31);
103 	z = u[11];
104 	u[6] ^= (z >> 18);
105 	u[5] ^= (z << 14) ^ (z >> 1);
106 	u[4] ^= (z << 31);
107 	z = u[10];
108 	u[5] ^= (z >> 18);
109 	u[4] ^= (z << 14) ^ (z >> 1);
110 	u[3] ^= (z << 31);
111 	z = u[9];
112 	u[4] ^= (z >> 18);
113 	u[3] ^= (z << 14) ^ (z >> 1);
114 	u[2] ^= (z << 31);
115 	z = u[8];
116 	u[3] ^= (z >> 18);
117 	u[2] ^= (z << 14) ^ (z >> 1);
118 	u[1] ^= (z << 31);
119 	z = u[7];
120 	u[2] ^= (z >> 18);
121 	u[1] ^= (z << 14) ^ (z >> 1);
122 	u[0] ^= (z << 31);
123 	z = u[6] >> 1;				/* z only has 31 significant bits */
124 	u[1] ^= (z >> 17);
125 	u[0] ^= (z << 15) ^ z;
126 	/* clear bits above 193 */
127 	u[12] = u[11] = u[10] = u[9] = u[8] = u[7] = 0;
128 	u[6] ^= z << 1;
129 #endif
130 	s_mp_clamp(r);
131 
132   CLEANUP:
133 	return res;
134 }
135 
136 /* Fast squaring for polynomials over a 193-bit curve. Assumes reduction
137  * polynomial with terms {193, 15, 0}. */
138 mp_err
ec_GF2m_193_sqr(const mp_int * a,mp_int * r,const GFMethod * meth)139 ec_GF2m_193_sqr(const mp_int *a, mp_int *r, const GFMethod *meth)
140 {
141 	mp_err res = MP_OKAY;
142 	mp_digit *u, *v;
143 
144 	v = MP_DIGITS(a);
145 
146 #ifdef ECL_SIXTY_FOUR_BIT
147 	if (MP_USED(a) < 4) {
148 		return mp_bsqrmod(a, meth->irr_arr, r);
149 	}
150 	if (MP_USED(r) < 7) {
151 		MP_CHECKOK(s_mp_pad(r, 7));
152 	}
153 	MP_USED(r) = 7;
154 #else
155 	if (MP_USED(a) < 7) {
156 		return mp_bsqrmod(a, meth->irr_arr, r);
157 	}
158 	if (MP_USED(r) < 13) {
159 		MP_CHECKOK(s_mp_pad(r, 13));
160 	}
161 	MP_USED(r) = 13;
162 #endif
163 	u = MP_DIGITS(r);
164 
165 #ifdef ECL_THIRTY_TWO_BIT
166 	u[12] = gf2m_SQR0(v[6]);
167 	u[11] = gf2m_SQR1(v[5]);
168 	u[10] = gf2m_SQR0(v[5]);
169 	u[9] = gf2m_SQR1(v[4]);
170 	u[8] = gf2m_SQR0(v[4]);
171 	u[7] = gf2m_SQR1(v[3]);
172 #endif
173 	u[6] = gf2m_SQR0(v[3]);
174 	u[5] = gf2m_SQR1(v[2]);
175 	u[4] = gf2m_SQR0(v[2]);
176 	u[3] = gf2m_SQR1(v[1]);
177 	u[2] = gf2m_SQR0(v[1]);
178 	u[1] = gf2m_SQR1(v[0]);
179 	u[0] = gf2m_SQR0(v[0]);
180 	return ec_GF2m_193_mod(r, r, meth);
181 
182   CLEANUP:
183 	return res;
184 }
185 
186 /* Fast multiplication for polynomials over a 193-bit curve. Assumes
187  * reduction polynomial with terms {193, 15, 0}. */
188 mp_err
ec_GF2m_193_mul(const mp_int * a,const mp_int * b,mp_int * r,const GFMethod * meth)189 ec_GF2m_193_mul(const mp_int *a, const mp_int *b, mp_int *r,
190 				const GFMethod *meth)
191 {
192 	mp_err res = MP_OKAY;
193 	mp_digit a3 = 0, a2 = 0, a1 = 0, a0, b3 = 0, b2 = 0, b1 = 0, b0;
194 
195 #ifdef ECL_THIRTY_TWO_BIT
196 	mp_digit a6 = 0, a5 = 0, a4 = 0, b6 = 0, b5 = 0, b4 = 0;
197 	mp_digit rm[8];
198 #endif
199 
200 	if (a == b) {
201 		return ec_GF2m_193_sqr(a, r, meth);
202 	} else {
203 		switch (MP_USED(a)) {
204 #ifdef ECL_THIRTY_TWO_BIT
205 		case 7:
206 			a6 = MP_DIGIT(a, 6);
207 			/* FALLTHROUGH */
208 		case 6:
209 			a5 = MP_DIGIT(a, 5);
210 			/* FALLTHROUGH */
211 		case 5:
212 			a4 = MP_DIGIT(a, 4);
213 #endif
214 			/* FALLTHROUGH */
215 		case 4:
216 			a3 = MP_DIGIT(a, 3);
217 			/* FALLTHROUGH */
218 		case 3:
219 			a2 = MP_DIGIT(a, 2);
220 			/* FALLTHROUGH */
221 		case 2:
222 			a1 = MP_DIGIT(a, 1);
223 			/* FALLTHROUGH */
224 		default:
225 			a0 = MP_DIGIT(a, 0);
226 		}
227 		switch (MP_USED(b)) {
228 #ifdef ECL_THIRTY_TWO_BIT
229 		case 7:
230 			b6 = MP_DIGIT(b, 6);
231 			/* FALLTHROUGH */
232 		case 6:
233 			b5 = MP_DIGIT(b, 5);
234 			/* FALLTHROUGH */
235 		case 5:
236 			b4 = MP_DIGIT(b, 4);
237 #endif
238 			/* FALLTHROUGH */
239 		case 4:
240 			b3 = MP_DIGIT(b, 3);
241 			/* FALLTHROUGH */
242 		case 3:
243 			b2 = MP_DIGIT(b, 2);
244 			/* FALLTHROUGH */
245 		case 2:
246 			b1 = MP_DIGIT(b, 1);
247 			/* FALLTHROUGH */
248 		default:
249 			b0 = MP_DIGIT(b, 0);
250 		}
251 #ifdef ECL_SIXTY_FOUR_BIT
252 		MP_CHECKOK(s_mp_pad(r, 8));
253 		s_bmul_4x4(MP_DIGITS(r), a3, a2, a1, a0, b3, b2, b1, b0);
254 		MP_USED(r) = 8;
255 		s_mp_clamp(r);
256 #else
257 		MP_CHECKOK(s_mp_pad(r, 14));
258 		s_bmul_3x3(MP_DIGITS(r) + 8, a6, a5, a4, b6, b5, b4);
259 		s_bmul_4x4(MP_DIGITS(r), a3, a2, a1, a0, b3, b2, b1, b0);
260 		s_bmul_4x4(rm, a3, a6 ^ a2, a5 ^ a1, a4 ^ a0, b3, b6 ^ b2, b5 ^ b1,
261 				   b4 ^ b0);
262 		rm[7] ^= MP_DIGIT(r, 7);
263 		rm[6] ^= MP_DIGIT(r, 6);
264 		rm[5] ^= MP_DIGIT(r, 5) ^ MP_DIGIT(r, 13);
265 		rm[4] ^= MP_DIGIT(r, 4) ^ MP_DIGIT(r, 12);
266 		rm[3] ^= MP_DIGIT(r, 3) ^ MP_DIGIT(r, 11);
267 		rm[2] ^= MP_DIGIT(r, 2) ^ MP_DIGIT(r, 10);
268 		rm[1] ^= MP_DIGIT(r, 1) ^ MP_DIGIT(r, 9);
269 		rm[0] ^= MP_DIGIT(r, 0) ^ MP_DIGIT(r, 8);
270 		MP_DIGIT(r, 11) ^= rm[7];
271 		MP_DIGIT(r, 10) ^= rm[6];
272 		MP_DIGIT(r, 9) ^= rm[5];
273 		MP_DIGIT(r, 8) ^= rm[4];
274 		MP_DIGIT(r, 7) ^= rm[3];
275 		MP_DIGIT(r, 6) ^= rm[2];
276 		MP_DIGIT(r, 5) ^= rm[1];
277 		MP_DIGIT(r, 4) ^= rm[0];
278 		MP_USED(r) = 14;
279 		s_mp_clamp(r);
280 #endif
281 		return ec_GF2m_193_mod(r, r, meth);
282 	}
283 
284   CLEANUP:
285 	return res;
286 }
287 
288 /* Wire in fast field arithmetic for 193-bit curves. */
289 mp_err
ec_group_set_gf2m193(ECGroup * group,ECCurveName name)290 ec_group_set_gf2m193(ECGroup *group, ECCurveName name)
291 {
292 	group->meth->field_mod = &ec_GF2m_193_mod;
293 	group->meth->field_mul = &ec_GF2m_193_mul;
294 	group->meth->field_sqr = &ec_GF2m_193_sqr;
295 	return MP_OKAY;
296 }
297