3 * $Id: pgen.h,v 1.8 2004/04/01 12:50:09 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 /*----- Revision history --------------------------------------------------*
33 * Revision 1.8 2004/04/01 12:50:09 mdw
34 * Add cyclic group abstraction, with test code. Separate off exponentation
35 * functions for better static linking. Fix a buttload of bugs on the way.
36 * Generally ensure that negative exponents do inversion correctly. Add
37 * table of standard prime-field subgroups. (Binary field subgroups are
38 * currently unimplemented but easy to add if anyone ever finds a good one.)
40 * Revision 1.7 2000/08/18 19:16:12 mdw
41 * New event handler for showing in detail sub-prime generation.
43 * Revision 1.6 2000/06/17 11:52:12 mdw
46 * Revision 1.5 2000/02/12 18:21:03 mdw
47 * Overhaul of key management (again).
49 * Revision 1.4 1999/12/22 16:01:11 mdw
50 * Same file, completely different code. Main interface for new prime-
55 #ifndef CATACOMB_PGEN_H
56 #define CATACOMB_PGEN_H
62 /*----- Header files ------------------------------------------------------*/
64 #ifndef CATACOMB_GRAND_H
72 #ifndef CATACOMB_PFILT_H
76 #ifndef CATACOMB_RABIN_H
80 /*----- Event handling ----------------------------------------------------*
82 * Different programs and architectures will want to show progress of prime
83 * searches and similar processes in different ways. Of course, for simple
84 * searches, it's possible to use the @pfilt@ and @rabin@ functions and
85 * maintain control over the general control flow throughout the search.
87 * For more complex cases, this sort of control is undesirable. It's
88 * possible to specify an event handler which is informed in abstract about
89 * the search. The event handler can also request the search be aborted.
92 /* --- Event code constants --- *
94 * You're allowed to rely on the values of @PGEN_DONE@ and @PGEN_ABORT@.
98 PGEN_BEGIN
= 1, /* Search for value begins */
99 PGEN_TRY
, /* A new candidate has appeared */
100 PGEN_FAIL
, /* The candidate failed the test */
101 PGEN_PASS
, /* The candidate passed a test */
102 PGEN_DONE
= 0, /* A good value has been found */
103 PGEN_ABORT
= -1 /* The search has been aborted */
106 /* --- Event information --- *
108 * Note that the pseudorandom number generator supplied is not
109 * cryptographically strong.
112 typedef struct pgen_event
{
113 const char *name
; /* Which quantity is being found */
114 mp
*m
; /* Current value under test */
115 unsigned steps
; /* Number of candidates left */
116 unsigned tests
; /* Tests left before passing */
117 grand
*r
; /* Source of random numbers */
120 /*----- Prime search parameters -------------------------------------------*
122 * The prime search is parameterized in a large number of ways, although this
123 * isn't so much of a surprise given the different sorts of properties
124 * required from prime numbers in cryptographic applications.
126 * There are two main things which need to be configured: stepping, and
127 * testing. (Filtering is done as part of stepping.)
129 * The functions here provide a toolkit for constructing stepping and testing
130 * routines. In a lot of cases, the functions can be used directly; in
131 * others, simple bits of glue need be written.
133 * Two types of functions are defined: steppers and testers, but their
134 * interfaces are substantially similar. Each is given a request code, a
135 * context block and an event block. It is meant to update its context and
136 * the event block and return an event code.
138 * A call with a request of @PGEN_BEGIN@ asks the stepper or tester to
139 * initialize itself using the information in its event block and context. A
140 * return of @PGEN_FAIL@ reports an immediate failure; @PGEN_ABORT@ reports a
141 * fatal problem; @PGEN_DONE@ reports immediate success. @PGEN_TRY@ reports
142 * successful initialization and requests test iterations.
144 * A call to a stepper with a request of @PGEN_TRY@ asks it to step to the
145 * next possible candidate, replacing the value @m@ in the event block with
146 * the new candidate. A call to a tester with a request of @PGEN_TRY@
147 * runs one pass of the test. It should return @PGEN_FAIL@ to report a
148 * failure, @PGEN_PASS@ to report a success and request another iteration,
149 * @PGEN_DONE@ to report final acceptance and @PGEN_ABORT@ to terminate the
150 * search unsuccessfully. Note that even if the search is aborted, a
151 * shutdown request is still made.
153 * A call with a request of @PGEN_DONE@ closes down the stepper or tester.
154 * After a successful initialization (i.e., a return of something other than
155 * @PGEN_ABORT@), a shutdown call is guaranteed. The return code is ignored.
158 typedef int pgen_proc(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
160 /*----- Simple handler functions ------------------------------------------*/
162 /* --- @pgen_filter@ --- *
164 * A prime generation context contains the information required for the
165 * simple prime filter and tester presented here.
168 typedef struct pgen_filterctx
{
169 unsigned step
; /* Step size (set by client) */
170 pfilt f
; /* The rapid prime filter */
173 extern int pgen_filter(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
175 /* --- @pgen_jump@ --- *
177 * Similar to the standard @pgen_filter@, but jumps in large steps rather
181 typedef struct pgen_jumpctx
{
186 extern int pgen_jump(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
188 /* --- @pgen_test@ --- *
190 * Runs the Rabin-Miller primality test. The context block is simply a
194 extern int pgen_test(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
196 /*----- Safe prime functions ----------------------------------------------*/
198 /* --- @pgen_safestep@ --- *
200 * Steps two numbers, %$q$% and %$p = 2q + 1$%, such that neither has any
201 * small factors. %$p$% is put in the event block.
204 typedef struct pgen_safestepctx
{
208 extern int pgen_safestep(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
210 /* --- @pgen_safejump@ --- *
212 * Jumps two numbers, %$q$% and %$p = 2q + 1$% such that neither has any
216 typedef struct pgen_safejumpctx
{
221 extern int pgen_safejump(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
223 /* --- @pgen_safetest@ --- *
225 * Applies Rabin-Miller tests to %$p$% and %$(p - 1)/2$%.
228 typedef struct pgen_safetestctx
{
233 extern int pgen_safetest(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
235 /*----- Miscellaneous steppers and testers --------------------------------*/
237 typedef struct pgen_gcdstepctx
{
238 pfilt p
, jp
; /* Prime filter and step filter */
239 mp
*q
, *jq
; /* %$p - 1$%, and a step value*/
240 mp
*r
; /* Other argument for GCD */
241 mp
*g
; /* GCD output (must be inited) */
242 mp
*max
; /* Maximum permissible GCD */
245 /* --- @pgen_gcdstep@ --- *
247 * Steps @p@ and @q@, until @p@ has no small factors, and
248 * %$\gcd(p, r) \le max$%.
251 extern int pgen_gcdstep(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
253 /*----- Standard event handlers -------------------------------------------*/
255 /* --- @pgen_evspin@ --- *
257 * Displays a spinning baton to show progress.
260 extern int pgen_evspin(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
262 /* --- @pgen_ev@ --- *
264 * Traditional event handler, shows dots for each test.
267 extern int pgen_ev(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
269 /* --- @pgen_subev@ --- *
271 * Subsidiary event handler, mainly for Lim-Lee searches and so on.
274 extern int pgen_subev(int /*rq*/, pgen_event */
*ev*/
, void */
*p*/
);
276 /*----- The main driver ---------------------------------------------------*/
280 * Arguments: @const char *name@ = name of the value being searched for
281 * @mp *d@ = destination for resulting integer
282 * @mp *m@ = start value to pass to stepper
283 * @pgen_proc *event@ = event handler function
284 * @void *ectx@ = context argument for event andler
285 * @unsigned steps@ = number of steps to take in search
286 * @pgen_proc *step@ = stepper function to use
287 * @void *sctx@ = context argument for stepper
288 * @unsigned tests@ = number of tests to make
289 * @pgen_proc *test@ = tester function to use
290 * @void *tctx@ = context argument for tester
292 * Returns: If successful, @PGEN_DONE@; otherwise @PGEN_ABORT@.
294 * Use: A generalized prime-number search skeleton. Yes, that's a
295 * scary number of arguments.
298 extern mp
*pgen(const char */
*name*/
, mp */
*d*/
, mp */
*m*/
,
299 pgen_proc */
*event*/
, void */
*ectx*/
,
300 unsigned /*steps*/, pgen_proc */
*step*/
, void */
*sctx*/
,
301 unsigned /*tests*/, pgen_proc */
*test*/
, void */
*tctx*/
);
303 /* --- @pgen_primep@ --- *
305 * Arguments: @mp *p@ = a number to check
306 * @grand *gr@ = a random number source
308 * Returns: Nonzero if @p@ is really prime.
311 extern int pgen_primep(mp */
*p*/
, grand */
*gr*/
);
313 /*----- That's all, folks -------------------------------------------------*/