0f5ec153 |
1 | /* -*-c-*- |
2 | * |
b3f05084 |
3 | * $Id: pgen.h,v 1.3 1999/12/10 23:29:48 mdw Exp $ |
0f5ec153 |
4 | * |
5 | * Finding and testing prime numbers |
6 | * |
7 | * (c) 1999 Straylight/Edgeware |
8 | */ |
9 | |
10 | /*----- Licensing notice --------------------------------------------------* |
11 | * |
12 | * This file is part of Catacomb. |
13 | * |
14 | * Catacomb is free software; you can redistribute it and/or modify |
15 | * it under the terms of the GNU Library General Public License as |
16 | * published by the Free Software Foundation; either version 2 of the |
17 | * License, or (at your option) any later version. |
18 | * |
19 | * Catacomb is distributed in the hope that it will be useful, |
20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
22 | * GNU Library General Public License for more details. |
23 | * |
24 | * You should have received a copy of the GNU Library General Public |
25 | * License along with Catacomb; if not, write to the Free |
26 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
27 | * MA 02111-1307, USA. |
28 | */ |
29 | |
30 | /*----- Revision history --------------------------------------------------* |
31 | * |
32 | * $Log: pgen.h,v $ |
b3f05084 |
33 | * Revision 1.3 1999/12/10 23:29:48 mdw |
34 | * Change header file guard names. |
35 | * |
bd98b2df |
36 | * Revision 1.2 1999/11/20 22:23:05 mdw |
37 | * Add multiply-and-add function for Diffie-Hellman safe prime generation. |
38 | * |
0f5ec153 |
39 | * Revision 1.1 1999/11/19 13:17:57 mdw |
40 | * Prime number generator and tester. |
41 | * |
42 | */ |
43 | |
b3f05084 |
44 | #ifndef CATACOMB_PGEN_H |
45 | #define CATACOMB_PGEN_H |
0f5ec153 |
46 | |
47 | #ifdef __cplusplus |
48 | extern "C" { |
49 | #endif |
50 | |
51 | /*----- Header files ------------------------------------------------------*/ |
52 | |
b3f05084 |
53 | #ifndef CATACOMB_MP_H |
0f5ec153 |
54 | # include "mp.h" |
55 | #endif |
56 | |
b3f05084 |
57 | #ifndef CATACOMB_PTAB_H |
0f5ec153 |
58 | # include "ptab.h" |
59 | #endif |
60 | |
61 | /*----- Constants ---------------------------------------------------------*/ |
62 | |
63 | #define PGEN_COMPOSITE (-1) /* Number is definitely composite */ |
64 | #define PGEN_MAYBE (0) /* Number may be prime */ |
65 | #define PGEN_PRIME (1) /* Number is definitely prime */ |
66 | |
67 | /*----- Data structures ---------------------------------------------------*/ |
68 | |
69 | typedef struct pgen { |
70 | mp *m; |
71 | unsigned char r[NPRIME]; |
72 | } pgen; |
73 | |
74 | /*----- Functions provided ------------------------------------------------*/ |
75 | |
76 | /* --- @pgen_create@ --- * |
77 | * |
78 | * Arguments: @pgen *p@ = pointer to prime generation context |
79 | * @mp *m@ = pointer to initial number to test |
80 | * |
81 | * Returns: One of the @PGEN@ constants above. |
82 | * |
83 | * Use: Tests an initial number for primality by computing its |
84 | * residue modulo various small prime numbers. This is fairly |
85 | * quick, but not particularly certain. If a @PGEN_MAYBE@ |
86 | * result is returned, perform Rabin-Miller tests to confirm. |
87 | */ |
88 | |
89 | extern int pgen_create(pgen */*p*/, mp */*m*/); |
90 | |
91 | /* --- @pgen_destroy@ --- * |
92 | * |
93 | * Arguments: @pgen *p@ = pointer to prime generation context |
94 | * |
95 | * Returns: --- |
96 | * |
97 | * Use: Discards a context and all the resources it holds. |
98 | */ |
99 | |
100 | extern void pgen_destroy(pgen */*p*/); |
101 | |
102 | /* --- @pgen_step@ --- * |
103 | * |
104 | * Arguments: @pgen *p@ = pointer to prime generation context |
105 | * @mpw step@ = how much to step the number |
106 | * |
107 | * Returns: One of the @PGEN@ constants above. |
108 | * |
109 | * Use: Steps a number by a small amount. Stepping is much faster |
110 | * than initializing with a new number. The test performed is |
111 | * the same simple one used by @ptab_create@, so @PGEN_MAYBE@ |
112 | * results should be followed up by a Rabin-Miller test. |
113 | */ |
114 | |
115 | extern int pgen_step(pgen */*p*/, mpw /*step*/); |
116 | |
bd98b2df |
117 | /* --- @pgen_muladd@ --- * |
118 | * |
119 | * Arguments: @pgen *p@ = destination prime generation context |
120 | * @const pgen *q@ = source prime generation context |
121 | * @mpw m@ = number to multiply by |
122 | * @mpw a@ = number to add |
123 | * |
124 | * Returns: One of the @PGEN@ constants above. |
125 | * |
126 | * Use: Multiplies the number in a prime generation context by a |
127 | * small value and then adds a small value. The destination |
128 | * should either be uninitialized or the same as the source. |
129 | * |
130 | * Common things to do include multiplying by 2 and adding 0 to |
131 | * turn a prime into a jump for finding other primes with @q@ as |
132 | * a factor of @p - 1@, or multiplying by 2 and adding 1. |
133 | */ |
134 | |
135 | extern int pgen_muladd(pgen */*p*/, const pgen */*q*/, mpw /*m*/, mpw /*a*/); |
136 | |
0f5ec153 |
137 | /* --- @pgen_jump@ --- * |
138 | * |
139 | * Arguments: @pgen *p@ = pointer to prime generation context |
140 | * @pgen *j@ = pointer to another generation context |
141 | * |
142 | * Returns: One of the @PGEN@ constants above. |
143 | * |
144 | * Use: Steps a number by a large amount. Even so, jumping is much |
145 | * faster than initializing a new number. The test peformed is |
146 | * the same simple one used by @ptab_create@, so @PGEN_MAYBE@ |
147 | * results should be followed up by a Rabin-Miller test. |
148 | * |
149 | * Note that the number stored in the @j@ context is probably |
150 | * better off being even than prime. The important thing is |
151 | * that all of the residues for the number have already been |
152 | * computed. |
153 | */ |
154 | |
155 | extern int pgen_jump(pgen */*p*/, pgen */*j*/); |
156 | |
157 | /*----- That's all, folks -------------------------------------------------*/ |
158 | |
159 | #ifdef __cplusplus |
160 | } |
161 | #endif |
162 | |
163 | #endif |