catacomb.c: Handle Python's randomize hashing parameters properly.
[catacomb-python] / catacomb / __init__.py
CommitLineData
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1### -*-python-*-
2###
3### Setup for Catacomb/Python bindings
4###
5### (c) 2004 Straylight/Edgeware
6###
7
8###----- Licensing notice ---------------------------------------------------
9###
10### This file is part of the Python interface to Catacomb.
11###
12### Catacomb/Python is free software; you can redistribute it and/or modify
13### it under the terms of the GNU General Public License as published by
14### the Free Software Foundation; either version 2 of the License, or
15### (at your option) any later version.
16###
17### Catacomb/Python 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 General Public License for more details.
21###
22### You should have received a copy of the GNU General Public License
23### along with Catacomb/Python; if not, write to the Free Software Foundation,
24### Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
ed8cc62d 25
d7ab1bab 26import _base
27import types as _types
28from binascii import hexlify as _hexify, unhexlify as _unhexify
46e6ad89 29from sys import argv as _argv
30
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31###--------------------------------------------------------------------------
32### Basic stuff.
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33
34## For the benefit of the default keyreporter, we need the program na,e.
46e6ad89 35_base._ego(_argv[0])
d7ab1bab 36
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37## Initialize the module. Drag in the static methods of the various
38## classes; create names for the various known crypto algorithms.
d7ab1bab 39def _init():
40 d = globals()
41 b = _base.__dict__;
42 for i in b:
43 if i[0] != '_':
44 d[i] = b[i];
45 for i in ['MP', 'GF', 'Field',
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46 'ECPt', 'ECPtCurve', 'ECCurve', 'ECInfo',
47 'DHInfo', 'BinDHInfo', 'RSAPriv', 'BBSPriv',
48 'PrimeFilter', 'RabinMiller',
49 'Group', 'GE',
89157adc 50 'KeySZ', 'KeyData']:
d7ab1bab 51 c = d[i]
52 pre = '_' + i + '_'
53 plen = len(pre)
54 for j in b:
55 if j[:plen] == pre:
00401529 56 setattr(c, j[plen:], classmethod(b[j]))
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57 for i in [gcciphers, gchashes, gcmacs, gcprps]:
58 for c in i.itervalues():
d7ab1bab 59 d[c.name.replace('-', '_')] = c
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60 for c in gccrands.itervalues():
61 d[c.name.replace('-', '_') + 'rand'] = c
d7ab1bab 62_init()
63
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64## A handy function for our work: add the methods of a named class to an
65## existing class. This is how we write the Python-implemented parts of our
66## mostly-C types.
d7ab1bab 67def _augment(c, cc):
68 for i in cc.__dict__:
69 a = cc.__dict__[i]
70 if type(a) is _types.MethodType:
71 a = a.im_func
72 elif type(a) not in (_types.FunctionType, staticmethod, classmethod):
73 continue
74 setattr(c, i, a)
75
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76## Parsing functions tend to return the object parsed and the remainder of
77## the input. This checks that the remainder is input and, if so, returns
78## just the object.
79def _checkend(r):
80 x, rest = r
81 if rest != '':
82 raise SyntaxError, 'junk at end of string'
83 return x
84
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85###--------------------------------------------------------------------------
86### Bytestrings.
ed8cc62d 87
d7ab1bab 88class _tmp:
89 def fromhex(x):
90 return ByteString(_unhexify(x))
91 fromhex = staticmethod(fromhex)
92 def __hex__(me):
93 return _hexify(me)
94 def __repr__(me):
95 return 'bytes(%r)' % hex(me)
96_augment(ByteString, _tmp)
97bytes = ByteString.fromhex
98
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99###--------------------------------------------------------------------------
100### Multiprecision integers and binary polynomials.
ed8cc62d 101
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102def _split_rat(x):
103 if isinstance(x, Rat): return x._n, x._d
104 else: return x, 1
105class Rat (object):
106 def __new__(cls, a, b):
107 a, b = MP(a), MP(b)
108 q, r = divmod(a, b)
109 if r == 0: return q
110 g = b.gcd(r)
111 me = super(Rat, cls).__new__(cls)
112 me._n = a//g
113 me._d = b//g
114 return me
115 @property
116 def numer(me): return me._n
117 @property
118 def denom(me): return me._d
119 def __str__(me): return '%s/%s' % (me._n, me._d)
120 def __repr__(me): return 'Rat(%s, %s)' % (me._n, me._d)
121
122 def __add__(me, you):
123 n, d = _split_rat(you)
124 return Rat(me._n*d + n*me._d, d*me._d)
125 __radd__ = __add__
126 def __sub__(me, you):
127 n, d = _split_rat(you)
128 return Rat(me._n*d - n*me._d, d*me._d)
129 def __rsub__(me, you):
130 n, d = _split_rat(you)
131 return Rat(n*me._d - me._n*d, d*me._d)
132 def __mul__(me, you):
133 n, d = _split_rat(you)
134 return Rat(me._n*n, me._d*d)
135 def __div__(me, you):
136 n, d = _split_rat(you)
137 return Rat(me._n*d, me._d*n)
138 def __rdiv__(me, you):
139 n, d = _split_rat(you)
140 return Rat(me._d*n, me._n*d)
141 def __cmp__(me, you):
142 n, d = _split_rat(you)
143 return cmp(me._n*d, n*me._d)
144 def __rcmp__(me, you):
145 n, d = _split_rat(you)
146 return cmp(n*me._d, me._n*d)
147
d7ab1bab 148class _tmp:
149 def negp(x): return x < 0
150 def posp(x): return x > 0
151 def zerop(x): return x == 0
152 def oddp(x): return x.testbit(0)
153 def evenp(x): return not x.testbit(0)
154 def mont(x): return MPMont(x)
155 def barrett(x): return MPBarrett(x)
156 def reduce(x): return MPReduce(x)
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157 def __div__(me, you): return Rat(me, you)
158 def __rdiv__(me, you): return Rat(you, me)
d7ab1bab 159_augment(MP, _tmp)
160
d7ab1bab 161class _tmp:
fbc145f3 162 def zerop(x): return x == 0
ed8cc62d 163 def reduce(x): return GFReduce(x)
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164 def trace(x, y): return x.reduce().trace(y)
165 def halftrace(x, y): return x.reduce().halftrace(y)
166 def modsqrt(x, y): return x.reduce().sqrt(y)
167 def quadsolve(x, y): return x.reduce().quadsolve(y)
d7ab1bab 168_augment(GF, _tmp)
169
170class _tmp:
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171 def product(*arg):
172 'product(ITERABLE) or product(I, ...) -> PRODUCT'
173 return MPMul(*arg).done()
174 product = staticmethod(product)
175_augment(MPMul, _tmp)
176
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177###--------------------------------------------------------------------------
178### Abstract fields.
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179
180class _tmp:
d7ab1bab 181 def fromstring(str): return _checkend(Field.parse(str))
182 fromstring = staticmethod(fromstring)
183_augment(Field, _tmp)
184
185class _tmp:
186 def __repr__(me): return '%s(%sL)' % (type(me).__name__, me.p)
6d481bc6 187 def __hash__(me): return 0x114401de ^ hash(me.p)
d7ab1bab 188 def ec(me, a, b): return ECPrimeProjCurve(me, a, b)
189_augment(PrimeField, _tmp)
190
191class _tmp:
192 def __repr__(me): return '%s(%sL)' % (type(me).__name__, hex(me.p))
193 def ec(me, a, b): return ECBinProjCurve(me, a, b)
194_augment(BinField, _tmp)
195
196class _tmp:
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197 def __hash__(me): return 0x23e4701c ^ hash(me.p)
198_augment(BinPolyField, _tmp)
199
200class _tmp:
201 def __hash__(me):
202 h = 0x9a7d6240
203 h ^= hash(me.p)
204 h ^= 2*hash(me.beta) & 0xffffffff
205 return h
206_augment(BinNormField, _tmp)
207
208class _tmp:
d7ab1bab 209 def __str__(me): return str(me.value)
210 def __repr__(me): return '%s(%s)' % (repr(me.field), repr(me.value))
211_augment(FE, _tmp)
212
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213###--------------------------------------------------------------------------
214### Elliptic curves.
d7ab1bab 215
216class _tmp:
217 def __repr__(me):
218 return '%s(%r, %s, %s)' % (type(me).__name__, me.field, me.a, me.b)
219 def frombuf(me, s):
220 return ecpt.frombuf(me, s)
221 def fromraw(me, s):
222 return ecpt.fromraw(me, s)
223 def pt(me, *args):
5f959e50 224 return me(*args)
d7ab1bab 225_augment(ECCurve, _tmp)
226
227class _tmp:
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228 def __hash__(me):
229 h = 0x6751d341
230 h ^= hash(me.field)
231 h ^= 2*hash(me.a) ^ 0xffffffff
232 h ^= 5*hash(me.b) ^ 0xffffffff
233 return h
234_augment(ECPrimeCurve, _tmp)
235
236class _tmp:
237 def __hash__(me):
238 h = 0x2ac203c5
239 h ^= hash(me.field)
240 h ^= 2*hash(me.a) ^ 0xffffffff
241 h ^= 5*hash(me.b) ^ 0xffffffff
242 return h
243_augment(ECBinCurve, _tmp)
244
245class _tmp:
d7ab1bab 246 def __repr__(me):
247 if not me: return 'ECPt()'
248 return 'ECPt(%s, %s)' % (me.ix, me.iy)
249 def __str__(me):
250 if not me: return 'inf'
251 return '(%s, %s)' % (me.ix, me.iy)
252_augment(ECPt, _tmp)
253
254class _tmp:
255 def __repr__(me):
256 return 'ECInfo(curve = %r, G = %r, r = %s, h = %s)' % \
00401529 257 (me.curve, me.G, me.r, me.h)
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258 def __hash__(me):
259 h = 0x9bedb8de
260 h ^= hash(me.curve)
261 h ^= 2*hash(me.G) & 0xffffffff
262 return h
d7ab1bab 263 def group(me):
264 return ECGroup(me)
265_augment(ECInfo, _tmp)
266
267class _tmp:
268 def __repr__(me):
269 if not me: return '%r()' % (me.curve)
270 return '%r(%s, %s)' % (me.curve, me.x, me.y)
271 def __str__(me):
272 if not me: return 'inf'
273 return '(%s, %s)' % (me.x, me.y)
274_augment(ECPtCurve, _tmp)
275
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276###--------------------------------------------------------------------------
277### Key sizes.
ed8cc62d 278
d7ab1bab 279class _tmp:
280 def __repr__(me): return 'KeySZAny(%d)' % me.default
281 def check(me, sz): return True
282 def best(me, sz): return sz
283_augment(KeySZAny, _tmp)
284
285class _tmp:
286 def __repr__(me):
287 return 'KeySZRange(%d, %d, %d, %d)' % \
00401529 288 (me.default, me.min, me.max, me.mod)
d7ab1bab 289 def check(me, sz): return me.min <= sz <= me.max and sz % me.mod == 0
290 def best(me, sz):
291 if sz < me.min: raise ValueError, 'key too small'
292 elif sz > me.max: return me.max
293 else: return sz - (sz % me.mod)
294_augment(KeySZRange, _tmp)
295
296class _tmp:
297 def __repr__(me): return 'KeySZSet(%d, %s)' % (me.default, me.set)
298 def check(me, sz): return sz in me.set
299 def best(me, sz):
300 found = -1
301 for i in me.set:
302 if found < i <= sz: found = i
303 if found < 0: raise ValueError, 'key too small'
304 return found
305_augment(KeySZSet, _tmp)
306
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307###--------------------------------------------------------------------------
308### Abstract groups.
ed8cc62d 309
d7ab1bab 310class _tmp:
311 def __repr__(me):
312 return '%s(p = %s, r = %s, g = %s)' % \
00401529 313 (type(me).__name__, me.p, me.r, me.g)
d7ab1bab 314_augment(FGInfo, _tmp)
315
316class _tmp:
317 def group(me): return PrimeGroup(me)
318_augment(DHInfo, _tmp)
319
320class _tmp:
321 def group(me): return BinGroup(me)
322_augment(BinDHInfo, _tmp)
323
324class _tmp:
325 def __repr__(me):
326 return '%s(%r)' % (type(me).__name__, me.info)
327_augment(Group, _tmp)
328
329class _tmp:
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330 def __hash__(me):
331 info = me.info
332 h = 0xbce3cfe6
333 h ^= hash(info.p)
334 h ^= 2*hash(info.r) & 0xffffffff
335 h ^= 5*hash(info.g) & 0xffffffff
336 return h
337_augment(PrimeGroup, _tmp)
338
339class _tmp:
340 def __hash__(me):
341 info = me.info
342 h = 0x80695949
343 h ^= hash(info.p)
344 h ^= 2*hash(info.r) & 0xffffffff
345 h ^= 5*hash(info.g) & 0xffffffff
346 return h
347_augment(BinGroup, _tmp)
348
349class _tmp:
350 def __hash__(me): return 0x0ec23dab ^ hash(me.info)
351_augment(ECGroup, _tmp)
352
353class _tmp:
d7ab1bab 354 def __repr__(me):
355 return '%r(%r)' % (me.group, str(me))
356_augment(GE, _tmp)
357
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358###--------------------------------------------------------------------------
359### RSA encoding techniques.
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360
361class PKCS1Crypt (object):
d7ab1bab 362 def __init__(me, ep = '', rng = rand):
363 me.ep = ep
364 me.rng = rng
365 def encode(me, msg, nbits):
366 return _base._p1crypt_encode(msg, nbits, me.ep, me.rng)
367 def decode(me, ct, nbits):
368 return _base._p1crypt_decode(ct, nbits, me.ep, me.rng)
369
ed8cc62d 370class PKCS1Sig (object):
d7ab1bab 371 def __init__(me, ep = '', rng = rand):
372 me.ep = ep
373 me.rng = rng
374 def encode(me, msg, nbits):
375 return _base._p1sig_encode(msg, nbits, me.ep, me.rng)
376 def decode(me, msg, sig, nbits):
377 return _base._p1sig_decode(msg, sig, nbits, me.ep, me.rng)
378
ed8cc62d 379class OAEP (object):
d7ab1bab 380 def __init__(me, mgf = sha_mgf, hash = sha, ep = '', rng = rand):
381 me.mgf = mgf
382 me.hash = hash
383 me.ep = ep
384 me.rng = rng
385 def encode(me, msg, nbits):
386 return _base._oaep_encode(msg, nbits, me.mgf, me.hash, me.ep, me.rng)
387 def decode(me, ct, nbits):
388 return _base._oaep_decode(ct, nbits, me.mgf, me.hash, me.ep, me.rng)
389
ed8cc62d 390class PSS (object):
d7ab1bab 391 def __init__(me, mgf = sha_mgf, hash = sha, saltsz = None, rng = rand):
392 me.mgf = mgf
393 me.hash = hash
394 if saltsz is None:
395 saltsz = hash.hashsz
396 me.saltsz = saltsz
397 me.rng = rng
398 def encode(me, msg, nbits):
399 return _base._pss_encode(msg, nbits, me.mgf, me.hash, me.saltsz, me.rng)
400 def decode(me, msg, sig, nbits):
401 return _base._pss_decode(msg, sig, nbits,
00401529 402 me.mgf, me.hash, me.saltsz, me.rng)
d7ab1bab 403
404class _tmp:
405 def encrypt(me, msg, enc):
406 return me.pubop(enc.encode(msg, me.n.nbits))
407 def verify(me, msg, sig, enc):
408 if msg is None: return enc.decode(msg, me.pubop(sig), me.n.nbits)
409 try:
410 x = enc.decode(msg, me.pubop(sig), me.n.nbits)
411 return x is None or x == msg
412 except ValueError:
b2687a0a 413 return False
d7ab1bab 414_augment(RSAPub, _tmp)
415
416class _tmp:
417 def decrypt(me, ct, enc): return enc.decode(me.privop(ct), me.n.nbits)
418 def sign(me, msg, enc): return me.privop(enc.encode(msg, me.n.nbits))
419_augment(RSAPriv, _tmp)
420
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421###--------------------------------------------------------------------------
422### Built-in named curves and prime groups.
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423
424class _groupmap (object):
425 def __init__(me, map, nth):
426 me.map = map
427 me.nth = nth
428 me.i = [None] * (max(map.values()) + 1)
429 def __repr__(me):
430 return '{%s}' % ', '.join(['%r: %r' % (k, me[k]) for k in me])
431 def __contains__(me, k):
432 return k in me.map
433 def __getitem__(me, k):
434 i = me.map[k]
435 if me.i[i] is None:
436 me.i[i] = me.nth(i)
437 return me.i[i]
438 def __setitem__(me, k, v):
439 raise TypeError, "immutable object"
440 def __iter__(me):
441 return iter(me.map)
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442 def iterkeys(me):
443 return iter(me.map)
444 def itervalues(me):
445 for k in me:
446 yield me[k]
447 def iteritems(me):
448 for k in me:
449 yield k, me[k]
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450 def keys(me):
451 return [k for k in me]
452 def values(me):
453 return [me[k] for k in me]
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454 def items(me):
455 return [(k, me[k]) for k in me]
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456eccurves = _groupmap(_base._eccurves, ECInfo._curven)
457primegroups = _groupmap(_base._pgroups, DHInfo._groupn)
458bingroups = _groupmap(_base._bingroups, BinDHInfo._groupn)
459
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460###--------------------------------------------------------------------------
461### Prime number generation.
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462
463class PrimeGenEventHandler (object):
464 def pg_begin(me, ev):
465 return me.pg_try(ev)
466 def pg_done(me, ev):
467 return PGEN_DONE
468 def pg_abort(me, ev):
469 return PGEN_TRY
470 def pg_fail(me, ev):
471 return PGEN_TRY
472 def pg_pass(me, ev):
473 return PGEN_TRY
d7ab1bab 474
475class SophieGermainStepJump (object):
476 def pg_begin(me, ev):
477 me.lf = PrimeFilter(ev.x)
478 me.hf = me.lf.muladd(2, 1)
479 return me.cont(ev)
480 def pg_try(me, ev):
481 me.step()
482 return me.cont(ev)
483 def cont(me, ev):
484 while me.lf.status == PGEN_FAIL or me.hf.status == PGEN_FAIL:
485 me.step()
486 if me.lf.status == PGEN_ABORT or me.hf.status == PGEN_ABORT:
487 return PGEN_ABORT
488 ev.x = me.lf.x
489 if me.lf.status == PGEN_DONE and me.hf.status == PGEN_DONE:
490 return PGEN_DONE
491 return PGEN_TRY
492 def pg_done(me, ev):
493 del me.lf
494 del me.hf
495
496class SophieGermainStepper (SophieGermainStepJump):
497 def __init__(me, step):
498 me.lstep = step;
499 me.hstep = 2 * step
500 def step(me):
501 me.lf.step(me.lstep)
502 me.hf.step(me.hstep)
503
504class SophieGermainJumper (SophieGermainStepJump):
505 def __init__(me, jump):
506 me.ljump = PrimeFilter(jump);
507 me.hjump = me.ljump.muladd(2, 0)
508 def step(me):
509 me.lf.jump(me.ljump)
510 me.hf.jump(me.hjump)
511 def pg_done(me, ev):
512 del me.ljump
513 del me.hjump
514 SophieGermainStepJump.pg_done(me, ev)
515
516class SophieGermainTester (object):
517 def __init__(me):
518 pass
519 def pg_begin(me, ev):
520 me.lr = RabinMiller(ev.x)
521 me.hr = RabinMiller(2 * ev.x + 1)
522 def pg_try(me, ev):
523 lst = me.lr.test(ev.rng.range(me.lr.x))
524 if lst != PGEN_PASS and lst != PGEN_DONE:
525 return lst
526 rst = me.hr.test(ev.rng.range(me.hr.x))
527 if rst != PGEN_PASS and rst != PGEN_DONE:
528 return rst
529 if lst == PGEN_DONE and rst == PGEN_DONE:
530 return PGEN_DONE
531 return PGEN_PASS
532 def pg_done(me, ev):
533 del me.lr
534 del me.hr
535
d7ab1bab 536class PrimitiveStepper (PrimeGenEventHandler):
537 def __init__(me):
538 pass
539 def pg_try(me, ev):
540 ev.x = me.i.next()
541 return PGEN_TRY
542 def pg_begin(me, ev):
543 me.i = iter(smallprimes)
544 return me.pg_try(ev)
545
546class PrimitiveTester (PrimeGenEventHandler):
547 def __init__(me, mod, hh = [], exp = None):
548 me.mod = MPMont(mod)
549 me.exp = exp
550 me.hh = hh
551 def pg_try(me, ev):
552 x = ev.x
553 if me.exp is not None:
554 x = me.mod.exp(x, me.exp)
555 if x == 1: return PGEN_FAIL
556 for h in me.hh:
557 if me.mod.exp(x, h) == 1: return PGEN_FAIL
558 ev.x = x
559 return PGEN_DONE
560
561class SimulStepper (PrimeGenEventHandler):
562 def __init__(me, mul = 2, add = 1, step = 2):
563 me.step = step
564 me.mul = mul
565 me.add = add
566 def _stepfn(me, step):
567 if step <= 0:
568 raise ValueError, 'step must be positive'
569 if step <= MPW_MAX:
570 return lambda f: f.step(step)
571 j = PrimeFilter(step)
572 return lambda f: f.jump(j)
573 def pg_begin(me, ev):
574 x = ev.x
575 me.lf = PrimeFilter(x)
576 me.hf = PrimeFilter(x * me.mul + me.add)
577 me.lstep = me._stepfn(me.step)
578 me.hstep = me._stepfn(me.step * me.mul)
579 SimulStepper._cont(me, ev)
580 def pg_try(me, ev):
581 me._step()
582 me._cont(ev)
583 def _step(me):
584 me.lstep(me.lf)
585 me.hstep(me.hf)
586 def _cont(me, ev):
587 while me.lf.status == PGEN_FAIL or me.hf.status == PGEN_FAIL:
588 me._step()
589 if me.lf.status == PGEN_ABORT or me.hf.status == PGEN_ABORT:
590 return PGEN_ABORT
591 ev.x = me.lf.x
592 if me.lf.status == PGEN_DONE and me.hf.status == PGEN_DONE:
593 return PGEN_DONE
594 return PGEN_TRY
595 def pg_done(me, ev):
596 del me.lf
597 del me.hf
598 del me.lstep
599 del me.hstep
600
601class SimulTester (PrimeGenEventHandler):
602 def __init__(me, mul = 2, add = 1):
603 me.mul = mul
604 me.add = add
605 def pg_begin(me, ev):
606 x = ev.x
607 me.lr = RabinMiller(x)
608 me.hr = RabinMiller(x * me.mul + me.add)
609 def pg_try(me, ev):
610 lst = me.lr.test(ev.rng.range(me.lr.x))
611 if lst != PGEN_PASS and lst != PGEN_DONE:
612 return lst
613 rst = me.hr.test(ev.rng.range(me.hr.x))
614 if rst != PGEN_PASS and rst != PGEN_DONE:
615 return rst
616 if lst == PGEN_DONE and rst == PGEN_DONE:
617 return PGEN_DONE
618 return PGEN_PASS
619 def pg_done(me, ev):
620 del me.lr
621 del me.hr
622
623def sgprime(start, step = 2, name = 'p', event = pgen_nullev, nsteps = 0):
624 start = MP(start)
625 return pgen(start, name, SimulStepper(step = step), SimulTester(), event,
00401529 626 nsteps, RabinMiller.iters(start.nbits))
d7ab1bab 627
628def findprimitive(mod, hh = [], exp = None, name = 'g', event = pgen_nullev):
629 return pgen(0, name, PrimitiveStepper(), PrimitiveTester(mod, hh, exp),
00401529 630 event, 0, 1)
d7ab1bab 631
632def kcdsaprime(pbits, qbits, rng = rand,
00401529 633 event = pgen_nullev, name = 'p', nsteps = 0):
d7ab1bab 634 hbits = pbits - qbits
635 h = pgen(rng.mp(hbits, 1), name + ' [h]',
00401529
MW
636 PrimeGenStepper(2), PrimeGenTester(),
637 event, nsteps, RabinMiller.iters(hbits))
d7ab1bab 638 q = pgen(rng.mp(qbits, 1), name, SimulStepper(2 * h, 1, 2),
00401529 639 SimulTester(2 * h, 1), event, nsteps, RabinMiller.iters(qbits))
d7ab1bab 640 p = 2 * q * h + 1
641 return p, q, h
642
643#----- That's all, folks ----------------------------------------------------