| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * Prime generation glue |
| 4 | * |
| 5 | * (c) 1999 Straylight/Edgeware |
| 6 | */ |
| 7 | |
| 8 | /*----- Licensing notice --------------------------------------------------* |
| 9 | * |
| 10 | * This file is part of Catacomb. |
| 11 | * |
| 12 | * Catacomb is free software; you can redistribute it and/or modify |
| 13 | * it under the terms of the GNU Library General Public License as |
| 14 | * published by the Free Software Foundation; either version 2 of the |
| 15 | * License, or (at your option) any later version. |
| 16 | * |
| 17 | * Catacomb is distributed in the hope that it will be useful, |
| 18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 20 | * GNU Library General Public License for more details. |
| 21 | * |
| 22 | * You should have received a copy of the GNU Library General Public |
| 23 | * License along with Catacomb; if not, write to the Free |
| 24 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
| 25 | * MA 02111-1307, USA. |
| 26 | */ |
| 27 | |
| 28 | #ifndef CATACOMB_PGEN_H |
| 29 | #define CATACOMB_PGEN_H |
| 30 | |
| 31 | #ifdef __cplusplus |
| 32 | extern "C" { |
| 33 | #endif |
| 34 | |
| 35 | /*----- Header files ------------------------------------------------------*/ |
| 36 | |
| 37 | #ifndef CATACOMB_GRAND_H |
| 38 | # include "grand.h" |
| 39 | #endif |
| 40 | |
| 41 | #ifndef CATACOMB_MP_H |
| 42 | # include "mp.h" |
| 43 | #endif |
| 44 | |
| 45 | #ifndef CATACOMB_PFILT_H |
| 46 | # include "pfilt.h" |
| 47 | #endif |
| 48 | |
| 49 | #ifndef CATACOMB_RABIN_H |
| 50 | # include "rabin.h" |
| 51 | #endif |
| 52 | |
| 53 | /*----- Event handling ----------------------------------------------------* |
| 54 | * |
| 55 | * Different programs and architectures will want to show progress of prime |
| 56 | * searches and similar processes in different ways. Of course, for simple |
| 57 | * searches, it's possible to use the @pfilt@ and @rabin@ functions and |
| 58 | * maintain control over the general control flow throughout the search. |
| 59 | * |
| 60 | * For more complex cases, this sort of control is undesirable. It's |
| 61 | * possible to specify an event handler which is informed in abstract about |
| 62 | * the search. The event handler can also request the search be aborted. |
| 63 | */ |
| 64 | |
| 65 | /* --- Event code constants --- * |
| 66 | * |
| 67 | * You're allowed to rely on the values of @PGEN_DONE@ and @PGEN_ABORT@. |
| 68 | */ |
| 69 | |
| 70 | enum { |
| 71 | PGEN_BEGIN = 1, /* Search for value begins */ |
| 72 | PGEN_TRY, /* A new candidate has appeared */ |
| 73 | PGEN_FAIL, /* The candidate failed the test */ |
| 74 | PGEN_PASS, /* The candidate passed a test */ |
| 75 | PGEN_DONE = 0, /* A good value has been found */ |
| 76 | PGEN_ABORT = -1 /* The search has been aborted */ |
| 77 | }; |
| 78 | |
| 79 | /* --- Event information --- * |
| 80 | * |
| 81 | * Note that the pseudorandom number generator supplied is not |
| 82 | * cryptographically strong. |
| 83 | */ |
| 84 | |
| 85 | typedef struct pgen_event { |
| 86 | const char *name; /* Which quantity is being found */ |
| 87 | mp *m; /* Current value under test */ |
| 88 | unsigned steps; /* Number of candidates left */ |
| 89 | unsigned tests; /* Tests left before passing */ |
| 90 | grand *r; /* Source of random numbers */ |
| 91 | } pgen_event; |
| 92 | |
| 93 | /*----- Prime search parameters -------------------------------------------* |
| 94 | * |
| 95 | * The prime search is parameterized in a large number of ways, although this |
| 96 | * isn't so much of a surprise given the different sorts of properties |
| 97 | * required from prime numbers in cryptographic applications. |
| 98 | * |
| 99 | * There are two main things which need to be configured: stepping, and |
| 100 | * testing. (Filtering is done as part of stepping.) |
| 101 | * |
| 102 | * The functions here provide a toolkit for constructing stepping and testing |
| 103 | * routines. In a lot of cases, the functions can be used directly; in |
| 104 | * others, simple bits of glue need be written. |
| 105 | * |
| 106 | * Two types of functions are defined: steppers and testers, but their |
| 107 | * interfaces are substantially similar. Each is given a request code, a |
| 108 | * context block and an event block. It is meant to update its context and |
| 109 | * the event block and return an event code. |
| 110 | * |
| 111 | * A call with a request of @PGEN_BEGIN@ asks the stepper or tester to |
| 112 | * initialize itself using the information in its event block and context. A |
| 113 | * return of @PGEN_FAIL@ reports an immediate failure; @PGEN_ABORT@ reports a |
| 114 | * fatal problem; @PGEN_DONE@ reports immediate success. @PGEN_TRY@ reports |
| 115 | * successful initialization and requests test iterations. |
| 116 | * |
| 117 | * A call to a stepper with a request of @PGEN_TRY@ asks it to step to the |
| 118 | * next possible candidate, replacing the value @m@ in the event block with |
| 119 | * the new candidate. A call to a tester with a request of @PGEN_TRY@ |
| 120 | * runs one pass of the test. It should return @PGEN_FAIL@ to report a |
| 121 | * failure, @PGEN_PASS@ to report a success and request another iteration, |
| 122 | * @PGEN_DONE@ to report final acceptance and @PGEN_ABORT@ to terminate the |
| 123 | * search unsuccessfully. Note that even if the search is aborted, a |
| 124 | * shutdown request is still made. |
| 125 | * |
| 126 | * A call with a request of @PGEN_DONE@ closes down the stepper or tester. |
| 127 | * After a successful initialization (i.e., a return of something other than |
| 128 | * @PGEN_ABORT@), a shutdown call is guaranteed. The return code is ignored. |
| 129 | */ |
| 130 | |
| 131 | typedef int pgen_proc(int /*rq*/, pgen_event */*ev*/, void */*p*/); |
| 132 | |
| 133 | /*----- Simple handler functions ------------------------------------------*/ |
| 134 | |
| 135 | /* --- @pgen_filter@ --- * |
| 136 | * |
| 137 | * A prime generation context contains the information required for the |
| 138 | * simple prime filter and tester presented here. |
| 139 | */ |
| 140 | |
| 141 | typedef struct pgen_filterctx { |
| 142 | unsigned step; /* Step size (set by client) */ |
| 143 | pfilt f; /* The rapid prime filter */ |
| 144 | } pgen_filterctx; |
| 145 | |
| 146 | extern pgen_proc pgen_filter; |
| 147 | |
| 148 | /* --- @pgen_jump@ --- * |
| 149 | * |
| 150 | * Similar to the standard @pgen_filter@, but jumps in large steps rather |
| 151 | * than small ones. |
| 152 | */ |
| 153 | |
| 154 | typedef struct pgen_jumpctx { |
| 155 | const pfilt *j; |
| 156 | pfilt f; |
| 157 | } pgen_jumpctx; |
| 158 | |
| 159 | extern pgen_proc pgen_jump; |
| 160 | |
| 161 | /* --- @pgen_test@ --- * |
| 162 | * |
| 163 | * Runs the Rabin-Miller primality test. The context block is simply a |
| 164 | * @rabin@ context. |
| 165 | */ |
| 166 | |
| 167 | extern pgen_proc pgen_test; |
| 168 | |
| 169 | /*----- Simultaneous primality checking -----------------------------------*/ |
| 170 | |
| 171 | typedef struct pgen_simulprime { |
| 172 | mp *mul, *add; /* Arguments from the client */ |
| 173 | unsigned f; /* Flags, set by client, changed */ |
| 174 | #define PGENF_KEEP 1u /* Keep this prime's value */ |
| 175 | #define PGENF_JUMP 8u /* Use jump table, not stepping */ |
| 176 | pfilt p; /* This prime's filter */ |
| 177 | rabin r; /* Rabin testing context */ |
| 178 | union { |
| 179 | mpw step; /* The simple step to use */ |
| 180 | pfilt *jump; /* The jump to move by */ |
| 181 | mp *x; /* The result, if wanted */ |
| 182 | } u; |
| 183 | } pgen_simulprime; |
| 184 | |
| 185 | typedef struct pgen_simulctx { |
| 186 | pgen_simulprime *v; /* Vector of related primes */ |
| 187 | unsigned n; /* Size of the vector */ |
| 188 | mp *step; /* Basic stepping value */ |
| 189 | } pgen_simulctx; |
| 190 | |
| 191 | /* --- @pgen_simulstep@ --- * |
| 192 | * |
| 193 | * Step a collection of numbers simultaneously. |
| 194 | */ |
| 195 | |
| 196 | extern pgen_proc pgen_simulstep; |
| 197 | |
| 198 | /* --- @pgen_simultest@ --- * |
| 199 | * |
| 200 | * Test a collection of numbers simultaneously. |
| 201 | */ |
| 202 | |
| 203 | extern pgen_proc pgen_simultest; |
| 204 | |
| 205 | /*----- Miscellaneous steppers and testers --------------------------------*/ |
| 206 | |
| 207 | typedef struct pgen_gcdstepctx { |
| 208 | pfilt p, jp; /* Prime filter and step filter */ |
| 209 | mp *q, *jq; /* %$p - 1$%, and a step value*/ |
| 210 | mp *r; /* Other argument for GCD */ |
| 211 | mp *g; /* GCD output (must be inited) */ |
| 212 | mp *max; /* Maximum permissible GCD */ |
| 213 | } pgen_gcdstepctx; |
| 214 | |
| 215 | /* --- @pgen_gcdstep@ --- * |
| 216 | * |
| 217 | * Steps @p@ and @q@, until @p@ has no small factors, and |
| 218 | * %$\gcd(p, r) \le max$%. |
| 219 | */ |
| 220 | |
| 221 | extern pgen_proc pgen_gcdstep; |
| 222 | |
| 223 | /*----- Standard event handlers -------------------------------------------*/ |
| 224 | |
| 225 | /* --- @pgen_evspin@ --- * |
| 226 | * |
| 227 | * Displays a spinning baton to show progress. |
| 228 | */ |
| 229 | |
| 230 | extern pgen_proc pgen_evspin; |
| 231 | |
| 232 | /* --- @pgen_ev@ --- * |
| 233 | * |
| 234 | * Traditional event handler, shows dots for each test. |
| 235 | */ |
| 236 | |
| 237 | extern pgen_proc pgen_ev; |
| 238 | |
| 239 | /* --- @pgen_subev@ --- * |
| 240 | * |
| 241 | * Subsidiary event handler, mainly for Lim-Lee searches and so on. |
| 242 | */ |
| 243 | |
| 244 | extern pgen_proc pgen_subev; |
| 245 | |
| 246 | /*----- The main driver ---------------------------------------------------*/ |
| 247 | |
| 248 | /* --- @pgen@ --- * |
| 249 | * |
| 250 | * Arguments: @const char *name@ = name of the value being searched for |
| 251 | * @mp *d@ = destination for resulting integer |
| 252 | * @mp *m@ = start value to pass to stepper |
| 253 | * @pgen_proc *event@ = event handler function |
| 254 | * @void *ectx@ = context argument for event andler |
| 255 | * @unsigned steps@ = number of steps to take in search |
| 256 | * @pgen_proc *step@ = stepper function to use |
| 257 | * @void *sctx@ = context argument for stepper |
| 258 | * @unsigned tests@ = number of tests to make |
| 259 | * @pgen_proc *test@ = tester function to use |
| 260 | * @void *tctx@ = context argument for tester |
| 261 | * |
| 262 | * Returns: The resulting value, or null. |
| 263 | * |
| 264 | * Use: A generalized prime-number search skeleton. Yes, that's a |
| 265 | * scary number of arguments. |
| 266 | */ |
| 267 | |
| 268 | extern mp *pgen(const char */*name*/, mp */*d*/, mp */*m*/, |
| 269 | pgen_proc */*event*/, void */*ectx*/, |
| 270 | unsigned /*steps*/, pgen_proc */*step*/, void */*sctx*/, |
| 271 | unsigned /*tests*/, pgen_proc */*test*/, void */*tctx*/); |
| 272 | |
| 273 | /* --- @pgen_granfrob@ --- * |
| 274 | * |
| 275 | * Arguments: @mp *n@ = an integer to test |
| 276 | * @int a, b@ = coefficients; if @a@ is zero then choose |
| 277 | * automatically |
| 278 | * |
| 279 | * Returns: One of the @PGEN_...@ codes. |
| 280 | * |
| 281 | * Use: Performs a quadratic versoin of Grantham's Frobenius |
| 282 | * primality test, which is a simple extension of the standard |
| 283 | * Lucas test. |
| 284 | * |
| 285 | * If %$a^2 - 4 b$% is a perfect square then the test can't |
| 286 | * work; this function returns @PGEN_ABORT@ under these |
| 287 | * circumstances. |
| 288 | * |
| 289 | * If @a@ is zero on entry, then the function will choose |
| 290 | * suitable parameters deterministically -- i.e., it always |
| 291 | * chooses the same parameters for a given %$n$%. |
| 292 | */ |
| 293 | |
| 294 | extern int pgen_granfrob(mp */*n*/, int /*a*/, int /*b*/); |
| 295 | |
| 296 | /* --- @pgen_primep@ --- * |
| 297 | * |
| 298 | * Arguments: @mp *p@ = a number to check |
| 299 | * @grand *gr@ = a random number source |
| 300 | * |
| 301 | * Returns: Nonzero if @p@ is really prime. |
| 302 | */ |
| 303 | |
| 304 | extern int pgen_primep(mp */*p*/, grand */*gr*/); |
| 305 | |
| 306 | /*----- That's all, folks -------------------------------------------------*/ |
| 307 | |
| 308 | #ifdef __cplusplus |
| 309 | } |
| 310 | #endif |
| 311 | |
| 312 | #endif |