mdw@git.distorted.org.uk Git - catacomb-python/blob - catacomb/__init__.py

   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.
  25
  26 from __future__ import with_statement
  27
  28 from binascii import hexlify as _hexify, unhexlify as _unhexify
  29 from contextlib import contextmanager as _ctxmgr
  30 try: import DLFCN as _dlfcn
  31 except ImportError: _dlfcn = None
  32 import os as _os
  33 from struct import pack as _pack
  34 import sys as _sys
  35 import types as _types
  36
  37 ###--------------------------------------------------------------------------
  38 ### Import the main C extension module.
  39
  40 try:
  41   _dlflags = _odlflags = _sys.getdlopenflags()
  42 except AttributeError:
  43   _dlflags = _odlflags = -1
  44
  45 ## Set the `deep binding' flag.  Python has its own different MD5
  46 ## implementation, and some distributions export `md5_init' and friends so
  47 ## they override our versions, which doesn't end well.  Figure out how to
  48 ## turn this flag on so we don't have the problem.
  49 if _dlflags >= 0:
  50   try: _dlflags |= _dlfcn.RTLD_DEEPBIND
  51   except AttributeError:
  52     try: _dlflags |= _os.RTLD_DEEPBIND
  53     except AttributeError:
  54       if _os.uname()[0] == 'Linux': _dlflags |= 8 # magic knowledge
  55       else: pass # can't do this.
  56   _sys.setdlopenflags(_dlflags)
  57
  58 if _sys.version_info >= (3,): from . import _base
  59 else: import _base
  60
  61 if _odlflags >= 0:
  62   _sys.setdlopenflags(_odlflags)
  63
  64 del _dlflags, _odlflags
  65
  66 ###--------------------------------------------------------------------------
  67 ### Basic stuff.
  68
  69 ## For the benefit of the default keyreporter, we need the program name.
  70 _base._ego(_sys.argv[0])
  71
  72 ## Register our module.
  73 _base._set_home_module(_sys.modules[__name__])
  74 def default_lostexchook(why, ty, val, tb):
  75   """`catacomb.lostexchook(WHY, TY, VAL, TB)' reports lost exceptions."""
  76   _sys.stderr.write("\n\n!!! LOST EXCEPTION: %s\n" % why)
  77   _sys.excepthook(ty, val, tb)
  78   _sys.stderr.write("\n")
  79 lostexchook = default_lostexchook
  80
  81 ## Text/binary conversions.
  82 if _sys.version_info >= (3,):
  83   def _bin(s): return s.encode('iso8859-1')
  84 else:
  85   def _bin(s): return s
  86
  87 ## Iterating over dictionaries.
  88 if _sys.version_info >= (3,):
  89   def _iteritems(dict): return dict.items()
  90   def _itervalues(dict): return dict.values()
  91 else:
  92   def _iteritems(dict): return dict.iteritems()
  93   def _itervalues(dict): return dict.itervalues()
  94
  95 ## The built-in bignum type.
  96 try: long
  97 except NameError: _long = int
  98 else: _long = long
  99
 100 ## How to fix a name back into the right identifier.  Alas, the rules are not
 101 ## consistent.
 102 def _fixname(name):
 103
 104   ## Hyphens consistently become underscores.
 105   name = name.replace('-', '_')
 106
 107   ## But slashes might become underscores or just vanish.
 108   if name.startswith('salsa20'): name = name.replace('/', '')
 109   else: name = name.replace('/', '_')
 110
 111   ## Done.
 112   return name
 113
 114 ## Initialize the module.  Drag in the static methods of the various
 115 ## classes; create names for the various known crypto algorithms.
 116 def _init():
 117   d = globals()
 118   b = _base.__dict__;
 119   for i in b:
 120     if i[0] != '_':
 121       d[i] = b[i];
 122   for i in [gcciphers, gcaeads, gchashes, gcmacs, gcprps]:
 123     for c in _itervalues(i):
 124       d[_fixname(c.name)] = c
 125   for c in _itervalues(gccrands):
 126     d[_fixname(c.name + 'rand')] = c
 127 _init()
 128
 129 ## A handy function for our work: add the methods of a named class to an
 130 ## existing class.  This is how we write the Python-implemented parts of our
 131 ## mostly-C types.
 132 def _augment(c, cc):
 133   for i in cc.__dict__:
 134     a = cc.__dict__[i]
 135     if type(a) is _types.MethodType:
 136       a = a.im_func
 137     elif type(a) not in (_types.FunctionType, staticmethod, classmethod):
 138       continue
 139     setattr(c, i, a)
 140
 141 ## Parsing functions tend to return the object parsed and the remainder of
 142 ## the input.  This checks that the remainder is input and, if so, returns
 143 ## just the object.
 144 def _checkend(r):
 145   x, rest = r
 146   if rest != '':
 147     raise SyntaxError('junk at end of string')
 148   return x
 149
 150 ## Some pretty-printing utilities.
 151 PRINT_SECRETS = False
 152 def _clsname(me): return type(me).__name__
 153 def _repr_secret(thing, secretp = True):
 154   if not secretp or PRINT_SECRETS: return repr(thing)
 155   else: return '#<SECRET>'
 156 def _pp_str(me, pp, cyclep): pp.text(cyclep and '...' or str(me))
 157 def _pp_secret(pp, thing, secretp = True):
 158   if not secretp or PRINT_SECRETS: pp.pretty(thing)
 159   else: pp.text('#<SECRET>')
 160 def _pp_bgroup(pp, text):
 161   ind = len(text)
 162   pp.begin_group(ind, text)
 163   return ind
 164 def _pp_bgroup_tyname(pp, obj, open = '('):
 165   return _pp_bgroup(pp, _clsname(obj) + open)
 166 def _pp_kv(pp, k, v, secretp = False):
 167   ind = _pp_bgroup(pp, k + ' = ')
 168   _pp_secret(pp, v, secretp)
 169   pp.end_group(ind, '')
 170 def _pp_commas(pp, printfn, items):
 171   firstp = True
 172   for i in items:
 173     if firstp: firstp = False
 174     else: pp.text(','); pp.breakable()
 175     printfn(i)
 176 def _pp_dict(pp, items):
 177   def p(kv):
 178     k, v = kv
 179     pp.begin_group(0)
 180     pp.pretty(k)
 181     pp.text(':')
 182     pp.begin_group(2)
 183     pp.breakable()
 184     pp.pretty(v)
 185     pp.end_group(2)
 186     pp.end_group(0)
 187   _pp_commas(pp, p, items)
 188
 189 ###--------------------------------------------------------------------------
 190 ### Mappings.
 191
 192 if _sys.version_info >= (3,):
 193   class _tmp:
 194     def __str__(me): return '%s(%r)' % (type(me).__name__, list(me))
 195     __repr__ = __str__
 196     def _repr_pretty_(me, pp, cyclep):
 197       ind = _pp_bgroup_tyname(pp, me, '([')
 198       _pp_commas(pp, pp.pretty, me)
 199       pp.end_group(ind, '])')
 200   _augment(_base._KeyView, _tmp)
 201   _augment(_base._ValueView, _tmp)
 202   _augment(_base._ItemView, _tmp)
 203
 204 ###--------------------------------------------------------------------------
 205 ### Bytestrings.
 206
 207 class _tmp:
 208   def fromhex(x):
 209     return ByteString(_unhexify(x))
 210   fromhex = staticmethod(fromhex)
 211   if _sys.version_info >= (3,):
 212     def hex(me): return _hexify(me).decode()
 213   else:
 214     def hex(me): return _hexify(me)
 215     __hex__ = hex
 216   def __repr__(me):
 217     return 'bytes(%r)' % me.hex()
 218 _augment(ByteString, _tmp)
 219 ByteString.__hash__ = str.__hash__
 220 bytes = ByteString.fromhex
 221
 222 ###--------------------------------------------------------------------------
 223 ### Symmetric encryption.
 224
 225 class _tmp:
 226   def encrypt(me, n, m, tsz = None, h = ByteString.zero(0)):
 227     if tsz is None: tsz = me.__class__.tagsz.default
 228     e = me.enc(n, len(h), len(m), tsz)
 229     if not len(h): a = None
 230     else: a = e.aad().hash(h)
 231     c0 = e.encrypt(m)
 232     c1, t = e.done(aad = a)
 233     return c0 + c1, t
 234   def decrypt(me, n, c, t, h = ByteString.zero(0)):
 235     d = me.dec(n, len(h), len(c), len(t))
 236     if not len(h): a = None
 237     else: a = d.aad().hash(h)
 238     m = d.decrypt(c)
 239     m += d.done(t, aad = a)
 240     return m
 241 _augment(GAEKey, _tmp)
 242
 243 ###--------------------------------------------------------------------------
 244 ### Hashing.
 245
 246 class _tmp:
 247   def check(me, h):
 248     hh = me.done()
 249     return ctstreq(h, hh)
 250 _augment(GHash, _tmp)
 251 _augment(Poly1305Hash, _tmp)
 252
 253 class _tmp:
 254   def check(me, h):
 255     return ctstreq(h, me.done(len(h)))
 256 _augment(Shake, _tmp)
 257
 258 KMAC128.keysz = KeySZAny(16); KMAC128.tagsz = 16
 259 KMAC256.keysz = KeySZAny(32); KMAC256.tagsz = 32
 260
 261 ###--------------------------------------------------------------------------
 262 ### NaCl `secretbox'.
 263
 264 def secret_box(k, n, m):
 265   y, t = salsa20_naclbox(k).encrypt(n, m)
 266   return t + y
 267
 268 def secret_unbox(k, n, c):
 269   tsz = poly1305.tagsz
 270   return salsa20_naclbox(k).decrypt(n, c[tsz:], c[0:tsz])
 271
 272 ###--------------------------------------------------------------------------
 273 ### Multiprecision integers and binary polynomials.
 274
 275 class BaseRat (object):
 276   """Base class implementing fields of fractions over Euclidean domains."""
 277   def __new__(cls, a, b):
 278     a, b = cls.RING._implicit(a), cls.RING._implicit(b)
 279     q, r = divmod(a, b)
 280     if r == cls.ZERO: return q
 281     g = b.gcd(r)
 282     me = super(BaseRat, cls).__new__(cls)
 283     me._n = a//g
 284     me._d = b//g
 285     return me
 286   @property
 287   def numer(me): return me._n
 288   @property
 289   def denom(me): return me._d
 290   def __str__(me): return '%s/%s' % (me._n, me._d)
 291   def __repr__(me): return '%s(%s, %s)' % (_clsname(me), me._n, me._d)
 292   _repr_pretty_ = _pp_str
 293
 294   def _split_rat(me, x):
 295     if isinstance(x, me.__class__): return x._n, x._d
 296     else: return x, me.ONE
 297   def __add__(me, you):
 298     n, d = me._split_rat(you)
 299     return type(me)(me._n*d + n*me._d, d*me._d)
 300   __radd__ = __add__
 301   def __sub__(me, you):
 302     n, d = me._split_rat(you)
 303     return type(me)(me._n*d - n*me._d, d*me._d)
 304   def __rsub__(me, you):
 305     n, d = me._split_rat(you)
 306     return type(me)(n*me._d - me._n*d, d*me._d)
 307   def __mul__(me, you):
 308     n, d = me._split_rat(you)
 309     return type(me)(me._n*n, me._d*d)
 310   __rmul__ = __mul__
 311   def __truediv__(me, you):
 312     n, d = me._split_rat(you)
 313     return type(me)(me._n*d, me._d*n)
 314   def __rtruediv__(me, you):
 315     n, d = me._split_rat(you)
 316     return type(me)(me._d*n, me._n*d)
 317   if _sys.version_info < (3,):
 318     __div__ = __truediv__
 319     __rdiv__ = __rtruediv__
 320   def _order(me, you, op):
 321     n, d = me._split_rat(you)
 322     return op(me._n*d, n*me._d)
 323   def __eq__(me, you): return me._order(you, lambda x, y: x == y)
 324   def __ne__(me, you): return me._order(you, lambda x, y: x != y)
 325   def __le__(me, you): return me._order(you, lambda x, y: x <= y)
 326   def __lt__(me, you): return me._order(you, lambda x, y: x <  y)
 327   def __gt__(me, you): return me._order(you, lambda x, y: x >  y)
 328   def __ge__(me, you): return me._order(you, lambda x, y: x >= y)
 329
 330 class IntRat (BaseRat):
 331   RING = MP
 332   ZERO, ONE = MP(0), MP(1)
 333   def __new__(cls, a, b):
 334     if isinstance(a, float) or isinstance(b, float): return a/b
 335     return super(IntRat, cls).__new__(cls, a, b)
 336   def __float__(me): return float(me._n)/float(me._d)
 337
 338 class GFRat (BaseRat):
 339   RING = GF
 340   ZERO, ONE = GF(0), GF(1)
 341
 342 class _tmp:
 343   def negp(x): return x < 0
 344   def posp(x): return x > 0
 345   def zerop(x): return x == 0
 346   def oddp(x): return x.testbit(0)
 347   def evenp(x): return not x.testbit(0)
 348   def mont(x): return MPMont(x)
 349   def barrett(x): return MPBarrett(x)
 350   def reduce(x): return MPReduce(x)
 351   def __truediv__(me, you):
 352     if isinstance(you, float): return _long(me)/you
 353     else: return IntRat(me, you)
 354   def __rtruediv__(me, you):
 355     if isinstance(you, float): return you/_long(me)
 356     else: return IntRat(you, me)
 357   if _sys.version_info < (3,):
 358     __div__ = __truediv__
 359     __rdiv__ = __rtruediv__
 360   _repr_pretty_ = _pp_str
 361 _augment(MP, _tmp)
 362
 363 class _tmp:
 364   def zerop(x): return x == 0
 365   def reduce(x): return GFReduce(x)
 366   def trace(x, y): return x.reduce().trace(y)
 367   def halftrace(x, y): return x.reduce().halftrace(y)
 368   def modsqrt(x, y): return x.reduce().sqrt(y)
 369   def quadsolve(x, y): return x.reduce().quadsolve(y)
 370   def __truediv__(me, you): return GFRat(me, you)
 371   def __rtruediv__(me, you): return GFRat(you, me)
 372   if _sys.version_info < (3,):
 373     __div__ = __truediv__
 374     __rdiv__ = __rtruediv__
 375   _repr_pretty_ = _pp_str
 376 _augment(GF, _tmp)
 377
 378 class _tmp:
 379   def product(*arg):
 380     'product(ITERABLE) or product(I, ...) -> PRODUCT'
 381     return MPMul(*arg).done()
 382   product = staticmethod(product)
 383 _augment(MPMul, _tmp)
 384
 385 ###--------------------------------------------------------------------------
 386 ### Abstract fields.
 387
 388 class _tmp:
 389   def fromstring(str): return _checkend(Field.parse(str))
 390   fromstring = staticmethod(fromstring)
 391 _augment(Field, _tmp)
 392
 393 class _tmp:
 394   def __repr__(me): return '%s(%s)' % (_clsname(me), me.p)
 395   def __hash__(me): return 0x114401de ^ hash(me.p)
 396   def _repr_pretty_(me, pp, cyclep):
 397     ind = _pp_bgroup_tyname(pp, me)
 398     if cyclep: pp.text('...')
 399     else: pp.pretty(me.p)
 400     pp.end_group(ind, ')')
 401   def ec(me, a, b): return ECPrimeProjCurve(me, a, b)
 402 _augment(PrimeField, _tmp)
 403
 404 class _tmp:
 405   def __repr__(me): return '%s(%#x)' % (_clsname(me), me.p)
 406   def ec(me, a, b): return ECBinProjCurve(me, a, b)
 407   def _repr_pretty_(me, pp, cyclep):
 408     ind = _pp_bgroup_tyname(pp, me)
 409     if cyclep: pp.text('...')
 410     else: pp.text('%#x' % me.p)
 411     pp.end_group(ind, ')')
 412 _augment(BinField, _tmp)
 413
 414 class _tmp:
 415   def __hash__(me): return 0x23e4701c ^ hash(me.p)
 416 _augment(BinPolyField, _tmp)
 417
 418 class _tmp:
 419   def __hash__(me):
 420     h = 0x9a7d6240
 421     h ^=   hash(me.p)
 422     h ^= 2*hash(me.beta) & 0xffffffff
 423     return h
 424 _augment(BinNormField, _tmp)
 425
 426 class _tmp:
 427   def __str__(me): return str(me.value)
 428   def __repr__(me): return '%s(%s)' % (repr(me.field), repr(me.value))
 429   _repr_pretty_ = _pp_str
 430 _augment(FE, _tmp)
 431
 432 ###--------------------------------------------------------------------------
 433 ### Elliptic curves.
 434
 435 class _tmp:
 436   def __repr__(me):
 437     return '%s(%r, %s, %s)' % (_clsname(me), me.field, me.a, me.b)
 438   def _repr_pretty_(me, pp, cyclep):
 439     ind = _pp_bgroup_tyname(pp, me)
 440     if cyclep:
 441       pp.text('...')
 442     else:
 443       pp.pretty(me.field); pp.text(','); pp.breakable()
 444       pp.pretty(me.a); pp.text(','); pp.breakable()
 445       pp.pretty(me.b)
 446     pp.end_group(ind, ')')
 447   def fromstring(str): return _checkend(ECCurve.parse(str))
 448   fromstring = staticmethod(fromstring)
 449   def frombuf(me, s):
 450     return ecpt.frombuf(me, s)
 451   def fromraw(me, s):
 452     return ecpt.fromraw(me, s)
 453   def pt(me, *args):
 454     return me(*args)
 455 _augment(ECCurve, _tmp)
 456
 457 class _tmp:
 458   def __hash__(me):
 459     h = 0x6751d341
 460     h ^=   hash(me.field)
 461     h ^= 2*hash(me.a) ^ 0xffffffff
 462     h ^= 5*hash(me.b) ^ 0xffffffff
 463     return h
 464 _augment(ECPrimeCurve, _tmp)
 465
 466 class _tmp:
 467   def __hash__(me):
 468     h = 0x2ac203c5
 469     h ^=   hash(me.field)
 470     h ^= 2*hash(me.a) ^ 0xffffffff
 471     h ^= 5*hash(me.b) ^ 0xffffffff
 472     return h
 473 _augment(ECBinCurve, _tmp)
 474
 475 class _tmp:
 476   def __repr__(me):
 477     if not me: return '%s()' % _clsname(me)
 478     return '%s(%s, %s)' % (_clsname(me), me.ix, me.iy)
 479   def __str__(me):
 480     if not me: return 'inf'
 481     return '(%s, %s)' % (me.ix, me.iy)
 482   def _repr_pretty_(me, pp, cyclep):
 483     if cyclep:
 484       pp.text('...')
 485     elif not me:
 486       pp.text('inf')
 487     else:
 488       ind = _pp_bgroup(pp, '(')
 489       pp.pretty(me.ix); pp.text(','); pp.breakable()
 490       pp.pretty(me.iy)
 491       pp.end_group(ind, ')')
 492 _augment(ECPt, _tmp)
 493
 494 class _tmp:
 495   def __repr__(me):
 496     return '%s(curve = %r, G = %r, r = %s, h = %s)' % \
 497            (_clsname(me), me.curve, me.G, me.r, me.h)
 498   def _repr_pretty_(me, pp, cyclep):
 499     ind = _pp_bgroup_tyname(pp, me)
 500     if cyclep:
 501       pp.text('...')
 502     else:
 503       _pp_kv(pp, 'curve', me.curve); pp.text(','); pp.breakable()
 504       _pp_kv(pp, 'G', me.G); pp.text(','); pp.breakable()
 505       _pp_kv(pp, 'r', me.r); pp.text(','); pp.breakable()
 506       _pp_kv(pp, 'h', me.h)
 507     pp.end_group(ind, ')')
 508   def __hash__(me):
 509     h = 0x9bedb8de
 510     h ^=   hash(me.curve)
 511     h ^= 2*hash(me.G) & 0xffffffff
 512     return h
 513   def fromstring(str): return _checkend(ECInfo.parse(str))
 514   fromstring = staticmethod(fromstring)
 515   def group(me):
 516     return ECGroup(me)
 517 _augment(ECInfo, _tmp)
 518
 519 class _tmp:
 520   def __repr__(me):
 521     if not me: return '%r()' % (me.curve)
 522     return '%r(%s, %s)' % (me.curve, me.x, me.y)
 523   def __str__(me):
 524     if not me: return 'inf'
 525     return '(%s, %s)' % (me.x, me.y)
 526   def _repr_pretty_(me, pp, cyclep):
 527     if cyclep:
 528       pp.text('...')
 529     elif not me:
 530       pp.text('inf')
 531     else:
 532       ind = _pp_bgroup(pp, '(')
 533       pp.pretty(me.x); pp.text(','); pp.breakable()
 534       pp.pretty(me.y)
 535       pp.end_group(ind, ')')
 536 _augment(ECPtCurve, _tmp)
 537
 538 ###--------------------------------------------------------------------------
 539 ### Key sizes.
 540
 541 class _tmp:
 542   def __repr__(me): return '%s(%d)' % (_clsname(me), me.default)
 543   def check(me, sz): return True
 544   def best(me, sz): return sz
 545   def pad(me, sz): return sz
 546 _augment(KeySZAny, _tmp)
 547
 548 class _tmp:
 549   def __repr__(me):
 550     return '%s(%d, %d, %d, %d)' % \
 551            (_clsname(me), me.default, me.min, me.max, me.mod)
 552   def _repr_pretty_(me, pp, cyclep):
 553     ind = _pp_bgroup_tyname(pp, me)
 554     if cyclep:
 555       pp.text('...')
 556     else:
 557       pp.pretty(me.default); pp.text(','); pp.breakable()
 558       pp.pretty(me.min); pp.text(','); pp.breakable()
 559       pp.pretty(me.max); pp.text(','); pp.breakable()
 560       pp.pretty(me.mod)
 561     pp.end_group(ind, ')')
 562   def check(me, sz): return me.min <= sz <= me.max and sz%me.mod == 0
 563   def best(me, sz):
 564     if sz < me.min: raise ValueError('key too small')
 565     elif me.max is not None and sz > me.max: return me.max
 566     else: return sz - sz%me.mod
 567   def pad(me, sz):
 568     if me.max is not None and sz > me.max: raise ValueError('key too large')
 569     elif sz < me.min: return me.min
 570     else: sz += me.mod - 1; return sz - sz%me.mod
 571 _augment(KeySZRange, _tmp)
 572
 573 class _tmp:
 574   def __repr__(me): return '%s(%d, %s)' % (_clsname(me), me.default, me.set)
 575   def _repr_pretty_(me, pp, cyclep):
 576     ind = _pp_bgroup_tyname(pp, me)
 577     if cyclep:
 578       pp.text('...')
 579     else:
 580       pp.pretty(me.default); pp.text(','); pp.breakable()
 581       ind1 = _pp_bgroup(pp, '{')
 582       _pp_commas(pp, pp.pretty, me.set)
 583       pp.end_group(ind1, '}')
 584     pp.end_group(ind, ')')
 585   def check(me, sz): return sz in me.set
 586   def best(me, sz):
 587     found = -1
 588     for i in me.set:
 589       if found < i <= sz: found = i
 590     if found < 0: raise ValueError('key too small')
 591     return found
 592   def pad(me, sz):
 593     found = -1
 594     for i in me.set:
 595       if sz <= i and (found == -1 or i < found): found = i
 596     if found < 0: raise ValueError('key too large')
 597     return found
 598 _augment(KeySZSet, _tmp)
 599
 600 ###--------------------------------------------------------------------------
 601 ### Key data objects.
 602
 603 class _tmp:
 604   def merge(me, file, report = None):
 605     """KF.merge(FILE, [report = <built-in-reporter>])"""
 606     name = file.name
 607     lno = 1
 608     for line in file:
 609       me.mergeline(name, lno, line, report)
 610       lno += 1
 611     return me
 612   def __repr__(me): return '%s(%r)' % (_clsname(me), me.name)
 613 _augment(KeyFile, _tmp)
 614
 615 class _tmp:
 616   def extract(me, file, filter = ''):
 617     """KEY.extract(FILE, [filter = <any>])"""
 618     line = me.extractline(filter)
 619     file.write(line)
 620     return me
 621   def __repr__(me): return '%s(%r)' % (_clsname(me), me.fulltag)
 622 _augment(Key, _tmp)
 623
 624 class _tmp:
 625   def __repr__(me):
 626     return '%s({%s})' % (_clsname(me),
 627                          ', '.join(['%r: %r' % kv for kv in _iteritems(me)()]))
 628   def _repr_pretty_(me, pp, cyclep):
 629     ind = _pp_bgroup_tyname(pp, me)
 630     if cyclep: pp.text('...')
 631     else: _pp_dict(pp, _iteritems(me))
 632     pp.end_group(ind, ')')
 633 _augment(KeyAttributes, _tmp)
 634
 635 class _tmp:
 636   def __repr__(me):
 637     return '%s(%s, %r)' % (_clsname(me),
 638                            _repr_secret(me._guts(),
 639                                         not (me.flags & KF_NONSECRET)),
 640                            me.writeflags(me.flags))
 641   def _repr_pretty_(me, pp, cyclep):
 642     ind = _pp_bgroup_tyname(pp, me)
 643     if cyclep:
 644       pp.text('...')
 645     else:
 646       _pp_secret(pp, me._guts(), not (me.flags & KF_NONSECRET))
 647       pp.text(','); pp.breakable()
 648       pp.pretty(me.writeflags(me.flags))
 649     pp.end_group(ind, ')')
 650   def __hash__(me): return me._HASHBASE ^ hash(me._guts())
 651   def __eq__(me, kd):
 652     return type(me) == type(kd) and \
 653       me._guts() == kd._guts() and \
 654       me.flags == kd.flags
 655   def __ne__(me, kd):
 656     return not me == kd
 657 _augment(KeyData, _tmp)
 658
 659 class _tmp:
 660   def _guts(me): return me.bin
 661   def __eq__(me, kd):
 662     return isinstance(kd, KeyDataBinary) and me.bin == kd.bin
 663 _augment(KeyDataBinary, _tmp)
 664 KeyDataBinary._HASHBASE = 0x961755c3
 665
 666 class _tmp:
 667   def _guts(me): return me.ct
 668 _augment(KeyDataEncrypted, _tmp)
 669 KeyDataEncrypted._HASHBASE = 0xffe000d4
 670
 671 class _tmp:
 672   def _guts(me): return me.mp
 673 _augment(KeyDataMP, _tmp)
 674 KeyDataMP._HASHBASE = 0x1cb64d69
 675
 676 class _tmp:
 677   def _guts(me): return me.str
 678 _augment(KeyDataString, _tmp)
 679 KeyDataString._HASHBASE = 0x349c33ea
 680
 681 class _tmp:
 682   def _guts(me): return me.ecpt
 683 _augment(KeyDataECPt, _tmp)
 684 KeyDataECPt._HASHBASE = 0x2509718b
 685
 686 class _tmp:
 687   def __repr__(me):
 688     return '%s({%s})' % (_clsname(me),
 689                          ', '.join(['%r: %r' % kv for kv in _iteritems(me)]))
 690   def _repr_pretty_(me, pp, cyclep):
 691     ind = _pp_bgroup_tyname(pp, me, '({ ')
 692     if cyclep: pp.text('...')
 693     else: _pp_dict(pp, _iteritems(me))
 694     pp.end_group(ind, ' })')
 695   def __hash__(me):
 696     h = me._HASHBASE
 697     for k, v in _iteritems(me):
 698       h = ((h << 1) ^ 3*hash(k) ^ 5*hash(v))&0xffffffff
 699     return h
 700   def __eq__(me, kd):
 701     if type(me) != type(kd) or me.flags != kd.flags or len(me) != len(kd):
 702       return False
 703     for k, v in _iteritems(me):
 704       try: vv = kd[k]
 705       except KeyError: return False
 706       if v != vv: return False
 707     return True
 708 _augment(KeyDataStructured, _tmp)
 709 KeyDataStructured._HASHBASE = 0x85851b21
 710
 711 ###--------------------------------------------------------------------------
 712 ### Abstract groups.
 713
 714 class _tmp:
 715   def __repr__(me):
 716     return '%s(p = %s, r = %s, g = %s)' % (_clsname(me), me.p, me.r, me.g)
 717   def _repr_pretty_(me, pp, cyclep):
 718     ind = _pp_bgroup_tyname(pp, me)
 719     if cyclep:
 720       pp.text('...')
 721     else:
 722       _pp_kv(pp, 'p', me.p); pp.text(','); pp.breakable()
 723       _pp_kv(pp, 'r', me.r); pp.text(','); pp.breakable()
 724       _pp_kv(pp, 'g', me.g)
 725     pp.end_group(ind, ')')
 726 _augment(FGInfo, _tmp)
 727
 728 class _tmp:
 729   def group(me): return PrimeGroup(me)
 730 _augment(DHInfo, _tmp)
 731
 732 class _tmp:
 733   def group(me): return BinGroup(me)
 734 _augment(BinDHInfo, _tmp)
 735
 736 class _tmp:
 737   def __repr__(me):
 738     return '%s(%r)' % (_clsname(me), me.info)
 739   def _repr_pretty_(me, pp, cyclep):
 740     ind = _pp_bgroup_tyname(pp, me)
 741     if cyclep: pp.text('...')
 742     else: pp.pretty(me.info)
 743     pp.end_group(ind, ')')
 744 _augment(Group, _tmp)
 745
 746 class _tmp:
 747   def __hash__(me):
 748     info = me.info
 749     h = 0xbce3cfe6
 750     h ^=   hash(info.p)
 751     h ^= 2*hash(info.r) & 0xffffffff
 752     h ^= 5*hash(info.g) & 0xffffffff
 753     return h
 754   def _get_geval(me, x): return MP(x)
 755 _augment(PrimeGroup, _tmp)
 756
 757 class _tmp:
 758   def __hash__(me):
 759     info = me.info
 760     h = 0x80695949
 761     h ^=   hash(info.p)
 762     h ^= 2*hash(info.r) & 0xffffffff
 763     h ^= 5*hash(info.g) & 0xffffffff
 764     return h
 765   def _get_geval(me, x): return GF(x)
 766 _augment(BinGroup, _tmp)
 767
 768 class _tmp:
 769   def __hash__(me): return 0x0ec23dab ^ hash(me.info)
 770   def _get_geval(me, x): return x.toec()
 771 _augment(ECGroup, _tmp)
 772
 773 class _tmp:
 774   def __repr__(me):
 775     return '%r(%r)' % (me.group, str(me))
 776   def _repr_pretty_(me, pp, cyclep):
 777     pp.pretty(type(me)._get_geval(me))
 778 _augment(GE, _tmp)
 779
 780 ###--------------------------------------------------------------------------
 781 ### RSA encoding techniques.
 782
 783 class PKCS1Crypt (object):
 784   def __init__(me, ep = _bin(''), rng = rand):
 785     me.ep = ep
 786     me.rng = rng
 787   def encode(me, msg, nbits):
 788     return _base._p1crypt_encode(msg, nbits, me.ep, me.rng)
 789   def decode(me, ct, nbits):
 790     return _base._p1crypt_decode(ct, nbits, me.ep, me.rng)
 791
 792 class PKCS1Sig (object):
 793   def __init__(me, ep = _bin(''), rng = rand):
 794     me.ep = ep
 795     me.rng = rng
 796   def encode(me, msg, nbits):
 797     return _base._p1sig_encode(msg, nbits, me.ep, me.rng)
 798   def decode(me, msg, sig, nbits):
 799     return _base._p1sig_decode(msg, sig, nbits, me.ep, me.rng)
 800
 801 class OAEP (object):
 802   def __init__(me, mgf = sha_mgf, hash = sha, ep = _bin(''), rng = rand):
 803     me.mgf = mgf
 804     me.hash = hash
 805     me.ep = ep
 806     me.rng = rng
 807   def encode(me, msg, nbits):
 808     return _base._oaep_encode(msg, nbits, me.mgf, me.hash, me.ep, me.rng)
 809   def decode(me, ct, nbits):
 810     return _base._oaep_decode(ct, nbits, me.mgf, me.hash, me.ep, me.rng)
 811
 812 class PSS (object):
 813   def __init__(me, mgf = sha_mgf, hash = sha, saltsz = None, rng = rand):
 814     me.mgf = mgf
 815     me.hash = hash
 816     if saltsz is None:
 817       saltsz = hash.hashsz
 818     me.saltsz = saltsz
 819     me.rng = rng
 820   def encode(me, msg, nbits):
 821     return _base._pss_encode(msg, nbits, me.mgf, me.hash, me.saltsz, me.rng)
 822   def decode(me, msg, sig, nbits):
 823     return _base._pss_decode(msg, sig, nbits,
 824                              me.mgf, me.hash, me.saltsz, me.rng)
 825
 826 class _tmp:
 827   def encrypt(me, msg, enc):
 828     return me.pubop(enc.encode(msg, me.n.nbits))
 829   def verify(me, msg, sig, enc):
 830     if msg is None: return enc.decode(msg, me.pubop(sig), me.n.nbits)
 831     try:
 832       x = enc.decode(msg, me.pubop(sig), me.n.nbits)
 833       return x is None or x == msg
 834     except ValueError:
 835       return False
 836   def __repr__(me):
 837     return '%s(n = %r, e = %r)' % (_clsname(me), me.n, me.e)
 838   def _repr_pretty_(me, pp, cyclep):
 839     ind = _pp_bgroup_tyname(pp, me)
 840     if cyclep:
 841       pp.text('...')
 842     else:
 843       _pp_kv(pp, 'n', me.n); pp.text(','); pp.breakable()
 844       _pp_kv(pp, 'e', me.e)
 845     pp.end_group(ind, ')')
 846 _augment(RSAPub, _tmp)
 847
 848 class _tmp:
 849   def decrypt(me, ct, enc): return enc.decode(me.privop(ct), me.n.nbits)
 850   def sign(me, msg, enc): return me.privop(enc.encode(msg, me.n.nbits))
 851   def __repr__(me):
 852     return '%s(n = %r, e = %r, d = %s, ' \
 853       'p = %s, q = %s, dp = %s, dq = %s, q_inv = %s)' % \
 854       (_clsname(me), me.n, me.e,
 855        _repr_secret(me.d), _repr_secret(me.p), _repr_secret(me.q),
 856        _repr_secret(me.dp), _repr_secret(me.dq), _repr_secret(me.q_inv))
 857   def _repr_pretty_(me, pp, cyclep):
 858     ind = _pp_bgroup_tyname(pp, me)
 859     if cyclep:
 860       pp.text('...')
 861     else:
 862       _pp_kv(pp, 'n', me.n); pp.text(','); pp.breakable()
 863       _pp_kv(pp, 'e', me.e); pp.text(','); pp.breakable()
 864       _pp_kv(pp, 'd', me.d, secretp = True); pp.text(','); pp.breakable()
 865       _pp_kv(pp, 'p', me.p, secretp = True); pp.text(','); pp.breakable()
 866       _pp_kv(pp, 'q', me.q, secretp = True); pp.text(','); pp.breakable()
 867       _pp_kv(pp, 'dp', me.dp, secretp = True); pp.text(','); pp.breakable()
 868       _pp_kv(pp, 'dq', me.dq, secretp = True); pp.text(','); pp.breakable()
 869       _pp_kv(pp, 'q_inv', me.q_inv, secretp = True)
 870     pp.end_group(ind, ')')
 871 _augment(RSAPriv, _tmp)
 872
 873 ###--------------------------------------------------------------------------
 874 ### DSA and related schemes.
 875
 876 class _tmp:
 877   def __repr__(me): return '%s(G = %r, p = %r, hash = %r)' % \
 878         (_clsname(me), me.G, me.p, me.hash)
 879   def _repr_pretty_(me, pp, cyclep):
 880     ind = _pp_bgroup_tyname(pp, me)
 881     if cyclep:
 882       pp.text('...')
 883     else:
 884       _pp_kv(pp, 'G', me.G); pp.text(','); pp.breakable()
 885       _pp_kv(pp, 'p', me.p); pp.text(','); pp.breakable()
 886       _pp_kv(pp, 'hash', me.hash)
 887     pp.end_group(ind, ')')
 888 _augment(DSAPub, _tmp)
 889 _augment(KCDSAPub, _tmp)
 890
 891 class _tmp:
 892   def __repr__(me): return '%s(G = %r, u = %s, p = %r, hash = %r)' % \
 893       (_clsname(me), me.G, _repr_secret(me.u), me.p, me.hash)
 894   def _repr_pretty_(me, pp, cyclep):
 895     ind = _pp_bgroup_tyname(pp, me)
 896     if cyclep:
 897       pp.text('...')
 898     else:
 899       _pp_kv(pp, 'G', me.G); pp.text(','); pp.breakable()
 900       _pp_kv(pp, 'u', me.u, True); pp.text(','); pp.breakable()
 901       _pp_kv(pp, 'p', me.p); pp.text(','); pp.breakable()
 902       _pp_kv(pp, 'hash', me.hash)
 903     pp.end_group(ind, ')')
 904 _augment(DSAPriv, _tmp)
 905 _augment(KCDSAPriv, _tmp)
 906
 907 ###--------------------------------------------------------------------------
 908 ### Bernstein's elliptic curve crypto and related schemes.
 909
 910 X25519_BASE = MP(9).storel(32)
 911 X448_BASE = MP(5).storel(56)
 912
 913 Z128 = ByteString.zero(16)
 914
 915 class _BasePub (object):
 916   def __init__(me, pub, *args, **kw):
 917     if not me._PUBSZ.check(len(pub)): raise ValueError('bad public key')
 918     super(_BasePub, me).__init__(*args, **kw)
 919     me.pub = pub
 920   def __repr__(me): return '%s(pub = %r)' % (_clsname(me), me.pub)
 921   def _pp(me, pp): _pp_kv(pp, 'pub', me.pub)
 922   def _repr_pretty_(me, pp, cyclep):
 923     ind = _pp_bgroup_tyname(pp, me)
 924     if cyclep: pp.text('...')
 925     else: me._pp(pp)
 926     pp.end_group(ind, ')')
 927
 928 class _BasePriv (object):
 929   def __init__(me, priv, pub = None, *args, **kw):
 930     if not me._KEYSZ.check(len(priv)): raise ValueError('bad private key')
 931     if pub is None: pub = me._pubkey(priv)
 932     super(_BasePriv, me).__init__(pub = pub, *args, **kw)
 933     me.priv = priv
 934   @classmethod
 935   def generate(cls, rng = rand):
 936     return cls(rng.block(cls._KEYSZ.default))
 937   def __repr__(me):
 938     return '%s(priv = %d, pub = %r)' % \
 939         (_clsname(me), _repr_secret(me.priv), me.pub)
 940   def _pp(me, pp):
 941     _pp_kv(pp, 'priv', me.priv, secretp = True); pp.text(','); pp.breakable()
 942     super(_BasePriv, me)._pp(pp)
 943
 944 class _XDHPub (_BasePub):  pass
 945
 946 class _XDHPriv (_BasePriv):
 947   def _pubkey(me, priv): return me._op(priv, me._BASE)
 948   def agree(me, you): return me._op(me.priv, you.pub)
 949   def boxkey(me, recip): return me._hashkey(me.agree(recip))
 950   def box(me, recip, n, m): return secret_box(me.boxkey(recip), n, m)
 951   def unbox(me, recip, n, c): return secret_unbox(me.boxkey(recip), n, c)
 952
 953 class X25519Pub (_XDHPub):
 954   _PUBSZ = KeySZSet(X25519_PUBSZ)
 955   _BASE = X25519_BASE
 956
 957 class X25519Priv (_XDHPriv, X25519Pub):
 958   _KEYSZ = KeySZSet(X25519_KEYSZ)
 959   def _op(me, k, X): return x25519(k, X)
 960   def _hashkey(me, z): return hsalsa20_prf(z, Z128)
 961
 962 class X448Pub (_XDHPub):
 963   _PUBSZ = KeySZSet(X448_PUBSZ)
 964   _BASE = X448_BASE
 965
 966 class X448Priv (_XDHPriv, X448Pub):
 967   _KEYSZ = KeySZSet(X448_KEYSZ)
 968   def _op(me, k, X): return x448(k, X)
 969   def _hashkey(me, z): return Shake256().hash(z).done(salsa20.keysz.default)
 970
 971 class _EdDSAPub (_BasePub):
 972   def beginhash(me): return me._HASH()
 973   def endhash(me, h): return h.done()
 974
 975 class _EdDSAPriv (_BasePriv, _EdDSAPub):
 976   pass
 977
 978 class Ed25519Pub (_EdDSAPub):
 979   _PUBSZ = KeySZSet(ED25519_PUBSZ)
 980   _HASH = sha512
 981   def verify(me, msg, sig, **kw):
 982     return ed25519_verify(me.pub, msg, sig, **kw)
 983
 984 class Ed25519Priv (_EdDSAPriv, Ed25519Pub):
 985   _KEYSZ = KeySZAny(ED25519_KEYSZ)
 986   def _pubkey(me, priv): return ed25519_pubkey(priv)
 987   def sign(me, msg, **kw):
 988     return ed25519_sign(me.priv, msg, pub = me.pub, **kw)
 989
 990 class Ed448Pub (_EdDSAPub):
 991   _PUBSZ = KeySZSet(ED448_PUBSZ)
 992   _HASH = shake256
 993   def verify(me, msg, sig, **kw):
 994     return ed448_verify(me.pub, msg, sig, **kw)
 995
 996 class Ed448Priv (_EdDSAPriv, Ed448Pub):
 997   _KEYSZ = KeySZAny(ED448_KEYSZ)
 998   def _pubkey(me, priv): return ed448_pubkey(priv)
 999   def sign(me, msg, **kw):
1000     return ed448_sign(me.priv, msg, pub = me.pub, **kw)
1001
1002 ###--------------------------------------------------------------------------
1003 ### Built-in algorithm and group tables.
1004
1005 class _tmp:
1006   def __repr__(me):
1007     return '{%s}' % ', '.join(['%r: %r' % kv for kv in _iteritems(me)])
1008   def _repr_pretty_(me, pp, cyclep):
1009     ind = _pp_bgroup(pp, '{ ')
1010     if cyclep: pp.text('...')
1011     else: _pp_dict(pp, _iteritems(me))
1012     pp.end_group(ind, ' }')
1013 _augment(_base._MiscTable, _tmp)
1014
1015 ###--------------------------------------------------------------------------
1016 ### Prime number generation.
1017
1018 class PrimeGenEventHandler (object):
1019   def pg_begin(me, ev):
1020     return me.pg_try(ev)
1021   def pg_done(me, ev):
1022     return PGEN_DONE
1023   def pg_abort(me, ev):
1024     return PGEN_TRY
1025   def pg_fail(me, ev):
1026     return PGEN_TRY
1027   def pg_pass(me, ev):
1028     return PGEN_TRY
1029
1030 class SophieGermainStepJump (object):
1031   def pg_begin(me, ev):
1032     me.lf = PrimeFilter(ev.x)
1033     me.hf = me.lf.muladd(2, 1)
1034     return me.cont(ev)
1035   def pg_try(me, ev):
1036     me.step()
1037     return me.cont(ev)
1038   def cont(me, ev):
1039     while me.lf.status == PGEN_FAIL or me.hf.status == PGEN_FAIL:
1040       me.step()
1041     if me.lf.status == PGEN_ABORT or me.hf.status == PGEN_ABORT:
1042       return PGEN_ABORT
1043     ev.x = me.lf.x
1044     if me.lf.status == PGEN_DONE and me.hf.status == PGEN_DONE:
1045       return PGEN_DONE
1046     return PGEN_TRY
1047   def pg_done(me, ev):
1048     del me.lf
1049     del me.hf
1050
1051 class SophieGermainStepper (SophieGermainStepJump):
1052   def __init__(me, step):
1053     me.lstep = step;
1054     me.hstep = 2 * step
1055   def step(me):
1056     me.lf.step(me.lstep)
1057     me.hf.step(me.hstep)
1058
1059 class SophieGermainJumper (SophieGermainStepJump):
1060   def __init__(me, jump):
1061     me.ljump = PrimeFilter(jump);
1062     me.hjump = me.ljump.muladd(2, 0)
1063   def step(me):
1064     me.lf.jump(me.ljump)
1065     me.hf.jump(me.hjump)
1066   def pg_done(me, ev):
1067     del me.ljump
1068     del me.hjump
1069     SophieGermainStepJump.pg_done(me, ev)
1070
1071 class SophieGermainTester (object):
1072   def __init__(me):
1073     pass
1074   def pg_begin(me, ev):
1075     me.lr = RabinMiller(ev.x)
1076     me.hr = RabinMiller(2 * ev.x + 1)
1077   def pg_try(me, ev):
1078     lst = me.lr.test(ev.rng.range(me.lr.x))
1079     if lst != PGEN_PASS and lst != PGEN_DONE:
1080       return lst
1081     rst = me.hr.test(ev.rng.range(me.hr.x))
1082     if rst != PGEN_PASS and rst != PGEN_DONE:
1083       return rst
1084     if lst == PGEN_DONE and rst == PGEN_DONE:
1085       return PGEN_DONE
1086     return PGEN_PASS
1087   def pg_done(me, ev):
1088     del me.lr
1089     del me.hr
1090
1091 class PrimitiveStepper (PrimeGenEventHandler):
1092   def __init__(me):
1093     pass
1094   def pg_try(me, ev):
1095     ev.x = me.i.next()
1096     return PGEN_TRY
1097   def pg_begin(me, ev):
1098     me.i = iter(smallprimes)
1099     return me.pg_try(ev)
1100
1101 class PrimitiveTester (PrimeGenEventHandler):
1102   def __init__(me, mod, hh = [], exp = None):
1103     me.mod = MPMont(mod)
1104     me.exp = exp
1105     me.hh = hh
1106   def pg_try(me, ev):
1107     x = ev.x
1108     if me.exp is not None:
1109       x = me.mod.exp(x, me.exp)
1110       if x == 1: return PGEN_FAIL
1111     for h in me.hh:
1112       if me.mod.exp(x, h) == 1: return PGEN_FAIL
1113     ev.x = x
1114     return PGEN_DONE
1115
1116 class SimulStepper (PrimeGenEventHandler):
1117   def __init__(me, mul = 2, add = 1, step = 2):
1118     me.step = step
1119     me.mul = mul
1120     me.add = add
1121   def _stepfn(me, step):
1122     if step <= 0:
1123       raise ValueError('step must be positive')
1124     if step <= MPW_MAX:
1125       return lambda f: f.step(step)
1126     j = PrimeFilter(step)
1127     return lambda f: f.jump(j)
1128   def pg_begin(me, ev):
1129     x = ev.x
1130     me.lf = PrimeFilter(x)
1131     me.hf = PrimeFilter(x * me.mul + me.add)
1132     me.lstep = me._stepfn(me.step)
1133     me.hstep = me._stepfn(me.step * me.mul)
1134     SimulStepper._cont(me, ev)
1135   def pg_try(me, ev):
1136     me._step()
1137     me._cont(ev)
1138   def _step(me):
1139     me.lstep(me.lf)
1140     me.hstep(me.hf)
1141   def _cont(me, ev):
1142     while me.lf.status == PGEN_FAIL or me.hf.status == PGEN_FAIL:
1143       me._step()
1144     if me.lf.status == PGEN_ABORT or me.hf.status == PGEN_ABORT:
1145       return PGEN_ABORT
1146     ev.x = me.lf.x
1147     if me.lf.status == PGEN_DONE and me.hf.status == PGEN_DONE:
1148       return PGEN_DONE
1149     return PGEN_TRY
1150   def pg_done(me, ev):
1151     del me.lf
1152     del me.hf
1153     del me.lstep
1154     del me.hstep
1155
1156 class SimulTester (PrimeGenEventHandler):
1157   def __init__(me, mul = 2, add = 1):
1158     me.mul = mul
1159     me.add = add
1160   def pg_begin(me, ev):
1161     x = ev.x
1162     me.lr = RabinMiller(x)
1163     me.hr = RabinMiller(x * me.mul + me.add)
1164   def pg_try(me, ev):
1165     lst = me.lr.test(ev.rng.range(me.lr.x))
1166     if lst != PGEN_PASS and lst != PGEN_DONE:
1167       return lst
1168     rst = me.hr.test(ev.rng.range(me.hr.x))
1169     if rst != PGEN_PASS and rst != PGEN_DONE:
1170       return rst
1171     if lst == PGEN_DONE and rst == PGEN_DONE:
1172       return PGEN_DONE
1173     return PGEN_PASS
1174   def pg_done(me, ev):
1175     del me.lr
1176     del me.hr
1177
1178 def sgprime(start, step = 2, name = 'p', event = pgen_nullev, nsteps = 0):
1179   start = MP(start)
1180   return pgen(start, name, SimulStepper(step = step), SimulTester(), event,
1181               nsteps, RabinMiller.iters(start.nbits))
1182
1183 def findprimitive(mod, hh = [], exp = None, name = 'g', event = pgen_nullev):
1184   return pgen(0, name, PrimitiveStepper(), PrimitiveTester(mod, hh, exp),
1185               event, 0, 1)
1186
1187 def kcdsaprime(pbits, qbits, rng = rand,
1188                event = pgen_nullev, name = 'p', nsteps = 0):
1189   hbits = pbits - qbits - 1
1190   while True:
1191     h = pgen(rng.mp(hbits, 1), name + ' [h]',
1192              PrimeGenStepper(2), PrimeGenTester(),
1193              event, nsteps, RabinMiller.iters(hbits))
1194     while True:
1195       q0 = rng.mp(qbits, 1)
1196       p0 = 2*q0*h + 1
1197       if p0.nbits == pbits: break
1198     q = pgen(q0, name, SimulStepper(2*h, 1, 2),
1199              SimulTester(2 * h, 1), event, nsteps, RabinMiller.iters(qbits))
1200     p = 2*q*h + 1
1201     if q.nbits == qbits and p.nbits == pbits: return p, q, h
1202     elif nsteps: raise ValueError("prime generation failed")
1203
1204 #----- That's all, folks ----------------------------------------------------