3 * $Id: pgen.h,v 1.9 2004/04/08 01:36:15 mdw Exp $
5 * Prime generation glue
7 * (c) 1999 Straylight/Edgeware
10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of Catacomb.
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.
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.
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,
30 #ifndef CATACOMB_PGEN_H
31 #define CATACOMB_PGEN_H
37 /*----- Header files ------------------------------------------------------*/
39 #ifndef CATACOMB_GRAND_H
47 #ifndef CATACOMB_PFILT_H
51 #ifndef CATACOMB_RABIN_H
55 /*----- Event handling ----------------------------------------------------*
57 * Different programs and architectures will want to show progress of prime
58 * searches and similar processes in different ways. Of course, for simple
59 * searches, it's possible to use the @pfilt@ and @rabin@ functions and
60 * maintain control over the general control flow throughout the search.
62 * For more complex cases, this sort of control is undesirable. It's
63 * possible to specify an event handler which is informed in abstract about
64 * the search. The event handler can also request the search be aborted.
67 /* --- Event code constants --- *
69 * You're allowed to rely on the values of @PGEN_DONE@ and @PGEN_ABORT@.
73 PGEN_BEGIN
= 1, /* Search for value begins */
74 PGEN_TRY
, /* A new candidate has appeared */
75 PGEN_FAIL
, /* The candidate failed the test */
76 PGEN_PASS
, /* The candidate passed a test */
77 PGEN_DONE
= 0, /* A good value has been found */
78 PGEN_ABORT
= -1 /* The search has been aborted */
81 /* --- Event information --- *
83 * Note that the pseudorandom number generator supplied is not
84 * cryptographically strong.
87 typedef struct pgen_event
{
88 const char *name
; /* Which quantity is being found */
89 mp
*m
; /* Current value under test */
90 unsigned steps
; /* Number of candidates left */
91 unsigned tests
; /* Tests left before passing */
92 grand
*r
; /* Source of random numbers */
95 /*----- Prime search parameters -------------------------------------------*
97 * The prime search is parameterized in a large number of ways, although this
98 * isn't so much of a surprise given the different sorts of properties
99 * required from prime numbers in cryptographic applications.
101 * There are two main things which need to be configured: stepping, and
102 * testing. (Filtering is done as part of stepping.)
104 * The functions here provide a toolkit for constructing stepping and testing
105 * routines. In a lot of cases, the functions can be used directly; in
106 * others, simple bits of glue need be written.
108 * Two types of functions are defined: steppers and testers, but their
109 * interfaces are substantially similar. Each is given a request code, a
110 * context block and an event block. It is meant to update its context and
111 * the event block and return an event code.
113 * A call with a request of @PGEN_BEGIN@ asks the stepper or tester to
114 * initialize itself using the information in its event block and context. A
115 * return of @PGEN_FAIL@ reports an immediate failure; @PGEN_ABORT@ reports a
116 * fatal problem; @PGEN_DONE@ reports immediate success. @PGEN_TRY@ reports
117 * successful initialization and requests test iterations.
119 * A call to a stepper with a request of @PGEN_TRY@ asks it to step to the
120 * next possible candidate, replacing the value @m@ in the event block with
121 * the new candidate. A call to a tester with a request of @PGEN_TRY@
122 * runs one pass of the test. It should return @PGEN_FAIL@ to report a
123 * failure, @PGEN_PASS@ to report a success and request another iteration,
124 * @PGEN_DONE@ to report final acceptance and @PGEN_ABORT@ to terminate the
125 * search unsuccessfully. Note that even if the search is aborted, a
126 * shutdown request is still made.
128 * A call with a request of @PGEN_DONE@ closes down the stepper or tester.
129 * After a successful initialization (i.e., a return of something other than
130 * @PGEN_ABORT@), a shutdown call is guaranteed. The return code is ignored.
133 typedef int pgen_proc(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
135 /*----- Simple handler functions ------------------------------------------*/
137 /* --- @pgen_filter@ --- *
139 * A prime generation context contains the information required for the
140 * simple prime filter and tester presented here.
143 typedef struct pgen_filterctx
{
144 unsigned step
; /* Step size (set by client) */
145 pfilt f
; /* The rapid prime filter */
148 extern int pgen_filter(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
150 /* --- @pgen_jump@ --- *
152 * Similar to the standard @pgen_filter@, but jumps in large steps rather
156 typedef struct pgen_jumpctx
{
161 extern int pgen_jump(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
163 /* --- @pgen_test@ --- *
165 * Runs the Rabin-Miller primality test. The context block is simply a
169 extern int pgen_test(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
171 /*----- Safe prime functions ----------------------------------------------*/
173 /* --- @pgen_safestep@ --- *
175 * Steps two numbers, %$q$% and %$p = 2q + 1$%, such that neither has any
176 * small factors. %$p$% is put in the event block.
179 typedef struct pgen_safestepctx
{
183 extern int pgen_safestep(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
185 /* --- @pgen_safejump@ --- *
187 * Jumps two numbers, %$q$% and %$p = 2q + 1$% such that neither has any
191 typedef struct pgen_safejumpctx
{
196 extern int pgen_safejump(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
198 /* --- @pgen_safetest@ --- *
200 * Applies Rabin-Miller tests to %$p$% and %$(p - 1)/2$%.
203 typedef struct pgen_safetestctx
{
208 extern int pgen_safetest(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
210 /*----- Miscellaneous steppers and testers --------------------------------*/
212 typedef struct pgen_gcdstepctx
{
213 pfilt p
, jp
; /* Prime filter and step filter */
214 mp
*q
, *jq
; /* %$p - 1$%, and a step value*/
215 mp
*r
; /* Other argument for GCD */
216 mp
*g
; /* GCD output (must be inited) */
217 mp
*max
; /* Maximum permissible GCD */
220 /* --- @pgen_gcdstep@ --- *
222 * Steps @p@ and @q@, until @p@ has no small factors, and
223 * %$\gcd(p, r) \le max$%.
226 extern int pgen_gcdstep(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
228 /*----- Standard event handlers -------------------------------------------*/
230 /* --- @pgen_evspin@ --- *
232 * Displays a spinning baton to show progress.
235 extern int pgen_evspin(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
237 /* --- @pgen_ev@ --- *
239 * Traditional event handler, shows dots for each test.
242 extern int pgen_ev(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
244 /* --- @pgen_subev@ --- *
246 * Subsidiary event handler, mainly for Lim-Lee searches and so on.
249 extern int pgen_subev(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
251 /*----- The main driver ---------------------------------------------------*/
255 * Arguments: @const char *name@ = name of the value being searched for
256 * @mp *d@ = destination for resulting integer
257 * @mp *m@ = start value to pass to stepper
258 * @pgen_proc *event@ = event handler function
259 * @void *ectx@ = context argument for event andler
260 * @unsigned steps@ = number of steps to take in search
261 * @pgen_proc *step@ = stepper function to use
262 * @void *sctx@ = context argument for stepper
263 * @unsigned tests@ = number of tests to make
264 * @pgen_proc *test@ = tester function to use
265 * @void *tctx@ = context argument for tester
267 * Returns: If successful, @PGEN_DONE@; otherwise @PGEN_ABORT@.
269 * Use: A generalized prime-number search skeleton. Yes, that's a
270 * scary number of arguments.
273 extern mp
*pgen(const char */
*name*/
, mp */
*d*/
, mp */
*m*/
,
274 pgen_proc */
*event*/
, void */
*ectx*/
,
275 unsigned /*steps*/, pgen_proc */
*step*/
, void */
*sctx*/
,
276 unsigned /*tests*/, pgen_proc */
*test*/
, void */
*tctx*/
);
278 /* --- @pgen_primep@ --- *
280 * Arguments: @mp *p@ = a number to check
281 * @grand *gr@ = a random number source
283 * Returns: Nonzero if @p@ is really prime.
286 extern int pgen_primep(mp */
*p*/
, grand */
*gr*/
);
288 /*----- That's all, folks -------------------------------------------------*/