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 import _base
  59
  60 if _odlflags >= 0:
  61   _sys.setdlopenflags(_odlflags)
  62
  63 del _dlflags, _odlflags
  64
  65 ###--------------------------------------------------------------------------
  66 ### Basic stuff.
  67
  68 ## For the benefit of the default keyreporter, we need the program name.
  69 _base._ego(_sys.argv[0])
  70
  71 ## Register our module.
  72 _base._set_home_module(_sys.modules[__name__])
  73 def default_lostexchook(why, ty, val, tb):
  74   """`catacomb.lostexchook(WHY, TY, VAL, TB)' reports lost exceptions."""
  75   _sys.stderr.write("\n\n!!! LOST EXCEPTION: %s\n" % why)
  76   _sys.excepthook(ty, val, tb)
  77   _sys.stderr.write("\n")
  78 lostexchook = default_lostexchook
  79
  80 ## How to fix a name back into the right identifier.  Alas, the rules are not
  81 ## consistent.
  82 def _fixname(name):
  83
  84   ## Hyphens consistently become underscores.
  85   name = name.replace('-', '_')
  86
  87   ## But slashes might become underscores or just vanish.
  88   if name.startswith('salsa20'): name = name.replace('/', '')
  89   else: name = name.replace('/', '_')
  90
  91   ## Done.
  92   return name
  93
  94 ## Initialize the module.  Drag in the static methods of the various
  95 ## classes; create names for the various known crypto algorithms.
  96 def _init():
  97   d = globals()
  98   b = _base.__dict__;
  99   for i in b:
 100     if i[0] != '_':
 101       d[i] = b[i];
 102   for i in ['ByteString',
 103             'MP', 'GF', 'Field',
 104             'ECPt', 'ECPtCurve', 'ECCurve', 'ECInfo',
 105             'DHInfo', 'BinDHInfo', 'RSAPriv', 'BBSPriv',
 106             'PrimeFilter', 'RabinMiller',
 107             'Group', 'GE',
 108             'KeySZ', 'KeyData']:
 109     c = d[i]
 110     pre = '_' + i + '_'
 111     plen = len(pre)
 112     for j in b:
 113       if j[:plen] == pre:
 114         setattr(c, j[plen:], classmethod(b[j]))
 115   for i in [gcciphers, gchashes, gcmacs, gcprps]:
 116     for c in i.itervalues():
 117       d[_fixname(c.name)] = c
 118   for c in gccrands.itervalues():
 119     d[_fixname(c.name + 'rand')] = c
 120 _init()
 121
 122 ## A handy function for our work: add the methods of a named class to an
 123 ## existing class.  This is how we write the Python-implemented parts of our
 124 ## mostly-C types.
 125 def _augment(c, cc):
 126   for i in cc.__dict__:
 127     a = cc.__dict__[i]
 128     if type(a) is _types.MethodType:
 129       a = a.im_func
 130     elif type(a) not in (_types.FunctionType, staticmethod, classmethod):
 131       continue
 132     setattr(c, i, a)
 133
 134 ## Parsing functions tend to return the object parsed and the remainder of
 135 ## the input.  This checks that the remainder is input and, if so, returns
 136 ## just the object.
 137 def _checkend(r):
 138   x, rest = r
 139   if rest != '':
 140     raise SyntaxError, 'junk at end of string'
 141   return x
 142
 143 ## Some pretty-printing utilities.
 144 PRINT_SECRETS = False
 145 def _clsname(me): return type(me).__name__
 146 def _repr_secret(thing, secretp = True):
 147   if not secretp or PRINT_SECRETS: return repr(thing)
 148   else: return '#<SECRET>'
 149 def _pp_str(me, pp, cyclep): pp.text(cyclep and '...' or str(me))
 150 def _pp_secret(pp, thing, secretp = True):
 151   if not secretp or PRINT_SECRETS: pp.pretty(thing)
 152   else: pp.text('#<SECRET>')
 153 def _pp_bgroup(pp, text):
 154   ind = len(text)
 155   pp.begin_group(ind, text)
 156   return ind
 157 def _pp_bgroup_tyname(pp, obj, open = '('):
 158   return _pp_bgroup(pp, _clsname(obj) + open)
 159 def _pp_kv(pp, k, v, secretp = False):
 160   ind = _pp_bgroup(pp, k + ' = ')
 161   _pp_secret(pp, v, secretp)
 162   pp.end_group(ind, '')
 163 def _pp_commas(pp, printfn, items):
 164   firstp = True
 165   for i in items:
 166     if firstp: firstp = False
 167     else: pp.text(','); pp.breakable()
 168     printfn(i)
 169 def _pp_dict(pp, items):
 170   def p((k, v)):
 171     pp.begin_group(0)
 172     pp.pretty(k)
 173     pp.text(':')
 174     pp.begin_group(2)
 175     pp.breakable()
 176     pp.pretty(v)
 177     pp.end_group(2)
 178     pp.end_group(0)
 179   _pp_commas(pp, p, items)
 180
 181 ###--------------------------------------------------------------------------
 182 ### Bytestrings.
 183
 184 class _tmp:
 185   def fromhex(x):
 186     return ByteString(_unhexify(x))
 187   fromhex = staticmethod(fromhex)
 188   def __hex__(me):
 189     return _hexify(me)
 190   def __repr__(me):
 191     return 'bytes(%r)' % hex(me)
 192 _augment(ByteString, _tmp)
 193 ByteString.__hash__ = str.__hash__
 194 bytes = ByteString.fromhex
 195
 196 ###--------------------------------------------------------------------------
 197 ### Hashing.
 198
 199 class _tmp:
 200   def check(me, h):
 201     hh = me.done()
 202     return ctstreq(h, hh)
 203 _augment(GHash, _tmp)
 204 _augment(Poly1305Hash, _tmp)
 205
 206 class _HashBase (object):
 207   ## The standard hash methods.  Assume that `hash' is defined and returns
 208   ## the receiver.
 209   def hashu8(me, n): return me.hash(_pack('B', n))
 210   def hashu16l(me, n): return me.hash(_pack('<H', n))
 211   def hashu16b(me, n): return me.hash(_pack('>H', n))
 212   hashu16 = hashu16b
 213   def hashu32l(me, n): return me.hash(_pack('<L', n))
 214   def hashu32b(me, n): return me.hash(_pack('>L', n))
 215   hashu32 = hashu32b
 216   def hashu64l(me, n): return me.hash(_pack('<Q', n))
 217   def hashu64b(me, n): return me.hash(_pack('>Q', n))
 218   hashu64 = hashu64b
 219   def hashbuf8(me, s): return me.hashu8(len(s)).hash(s)
 220   def hashbuf16l(me, s): return me.hashu16l(len(s)).hash(s)
 221   def hashbuf16b(me, s): return me.hashu16b(len(s)).hash(s)
 222   hashbuf16 = hashbuf16b
 223   def hashbuf32l(me, s): return me.hashu32l(len(s)).hash(s)
 224   def hashbuf32b(me, s): return me.hashu32b(len(s)).hash(s)
 225   hashbuf32 = hashbuf32b
 226   def hashbuf64l(me, s): return me.hashu64l(len(s)).hash(s)
 227   def hashbuf64b(me, s): return me.hashu64b(len(s)).hash(s)
 228   hashbuf64 = hashbuf64b
 229   def hashstrz(me, s): return me.hash(s).hashu8(0)
 230
 231 class _ShakeBase (_HashBase):
 232
 233   ## Python gets really confused if I try to augment `__new__' on native
 234   ## classes, so wrap and delegate.  Sorry.
 235   def __init__(me, perso = '', *args, **kw):
 236     super(_ShakeBase, me).__init__(*args, **kw)
 237     me._h = me._SHAKE(perso = perso, func = me._FUNC)
 238
 239   ## Delegate methods...
 240   def copy(me): new = me.__class__(); new._copy(me)
 241   def _copy(me, other): me._h = other._h.copy()
 242   def hash(me, m): me._h.hash(m); return me
 243   def xof(me): me._h.xof(); return me
 244   def get(me, n): return me._h.get(n)
 245   def mask(me, m): return me._h.mask(m)
 246   def done(me, n): return me._h.done(n)
 247   def check(me, h): return ctstreq(h, me.done(len(h)))
 248   @property
 249   def state(me): return me._h.state
 250   @property
 251   def buffered(me): return me._h.buffered
 252   @property
 253   def rate(me): return me._h.rate
 254
 255 class _tmp:
 256   def check(me, h):
 257     return ctstreq(h, me.done(len(h)))
 258   def leftenc(me, n):
 259     nn = MP(n).storeb()
 260     return me.hashu8(len(nn)).hash(nn)
 261   def rightenc(me, n):
 262     nn = MP(n).storeb()
 263     return me.hash(nn).hashu8(len(nn))
 264   def stringenc(me, str):
 265     return me.leftenc(8*len(str)).hash(str)
 266   def bytepad_before(me):
 267     return me.leftenc(me.rate)
 268   def bytepad_after(me):
 269     if me.buffered: me.hash(me._Z[:me.rate - me.buffered])
 270     return me
 271   @_ctxmgr
 272   def bytepad(me):
 273     me.bytepad_before()
 274     yield me
 275     me.bytepad_after()
 276 _augment(Shake, _tmp)
 277 _augment(_ShakeBase, _tmp)
 278 Shake._Z = _ShakeBase._Z = ByteString(200*'\0')
 279
 280 class KMAC (_ShakeBase):
 281   _FUNC = 'KMAC'
 282   def __init__(me, k, *arg, **kw):
 283     super(KMAC, me).__init__(*arg, **kw)
 284     with me.bytepad(): me.stringenc(k)
 285   def done(me, n = -1):
 286     if n < 0: n = me._TAGSZ
 287     me.rightenc(8*n)
 288     return super(KMAC, me).done(n)
 289   def xof(me):
 290     me.rightenc(0)
 291     return super(KMAC, me).xof()
 292
 293 class KMAC128 (KMAC): _SHAKE = Shake128; _TAGSZ = 16
 294 class KMAC256 (KMAC): _SHAKE = Shake256; _TAGSZ = 32
 295
 296 ###--------------------------------------------------------------------------
 297 ### NaCl `secretbox'.
 298
 299 def secret_box(k, n, m):
 300   E = xsalsa20(k).setiv(n)
 301   r = E.enczero(poly1305.keysz.default)
 302   s = E.enczero(poly1305.masksz)
 303   y = E.encrypt(m)
 304   t = poly1305(r)(s).hash(y).done()
 305   return ByteString(t + y)
 306
 307 def secret_unbox(k, n, c):
 308   E = xsalsa20(k).setiv(n)
 309   r = E.enczero(poly1305.keysz.default)
 310   s = E.enczero(poly1305.masksz)
 311   y = c[poly1305.tagsz:]
 312   if not poly1305(r)(s).hash(y).check(c[0:poly1305.tagsz]):
 313     raise ValueError, 'decryption failed'
 314   return E.decrypt(c[poly1305.tagsz:])
 315
 316 ###--------------------------------------------------------------------------
 317 ### Multiprecision integers and binary polynomials.
 318
 319 def _split_rat(x):
 320   if isinstance(x, BaseRat): return x._n, x._d
 321   else: return x, 1
 322 class BaseRat (object):
 323   """Base class implementing fields of fractions over Euclidean domains."""
 324   def __new__(cls, a, b):
 325     a, b = cls.RING(a), cls.RING(b)
 326     q, r = divmod(a, b)
 327     if r == 0: return q
 328     g = b.gcd(r)
 329     me = super(BaseRat, cls).__new__(cls)
 330     me._n = a//g
 331     me._d = b//g
 332     return me
 333   @property
 334   def numer(me): return me._n
 335   @property
 336   def denom(me): return me._d
 337   def __str__(me): return '%s/%s' % (me._n, me._d)
 338   def __repr__(me): return '%s(%s, %s)' % (_clsname(me), me._n, me._d)
 339   _repr_pretty_ = _pp_str
 340
 341   def __add__(me, you):
 342     n, d = _split_rat(you)
 343     return type(me)(me._n*d + n*me._d, d*me._d)
 344   __radd__ = __add__
 345   def __sub__(me, you):
 346     n, d = _split_rat(you)
 347     return type(me)(me._n*d - n*me._d, d*me._d)
 348   def __rsub__(me, you):
 349     n, d = _split_rat(you)
 350     return type(me)(n*me._d - me._n*d, d*me._d)
 351   def __mul__(me, you):
 352     n, d = _split_rat(you)
 353     return type(me)(me._n*n, me._d*d)
 354   __rmul__ = __mul__
 355   def __truediv__(me, you):
 356     n, d = _split_rat(you)
 357     return type(me)(me._n*d, me._d*n)
 358   def __rtruediv__(me, you):
 359     n, d = _split_rat(you)
 360     return type(me)(me._d*n, me._n*d)
 361   __div__ = __truediv__
 362   __rdiv__ = __rtruediv__
 363   def __cmp__(me, you):
 364     n, d = _split_rat(you)
 365     return cmp(me._n*d, n*me._d)
 366   def __rcmp__(me, you):
 367     n, d = _split_rat(you)
 368     return cmp(n*me._d, me._n*d)
 369
 370 class IntRat (BaseRat):
 371   RING = MP
 372
 373 class GFRat (BaseRat):
 374   RING = GF
 375
 376 class _tmp:
 377   def negp(x): return x < 0
 378   def posp(x): return x > 0
 379   def zerop(x): return x == 0
 380   def oddp(x): return x.testbit(0)
 381   def evenp(x): return not x.testbit(0)
 382   def mont(x): return MPMont(x)
 383   def barrett(x): return MPBarrett(x)
 384   def reduce(x): return MPReduce(x)
 385   def __truediv__(me, you): return IntRat(me, you)
 386   def __rtruediv__(me, you): return IntRat(you, me)
 387   __div__ = __truediv__
 388   __rdiv__ = __rtruediv__
 389   _repr_pretty_ = _pp_str
 390 _augment(MP, _tmp)
 391
 392 class _tmp:
 393   def zerop(x): return x == 0
 394   def reduce(x): return GFReduce(x)
 395   def trace(x, y): return x.reduce().trace(y)
 396   def halftrace(x, y): return x.reduce().halftrace(y)
 397   def modsqrt(x, y): return x.reduce().sqrt(y)
 398   def quadsolve(x, y): return x.reduce().quadsolve(y)
 399   def __truediv__(me, you): return GFRat(me, you)
 400   def __rtruediv__(me, you): return GFRat(you, me)
 401   __div__ = __truediv__
 402   __rdiv__ = __rtruediv__
 403   _repr_pretty_ = _pp_str
 404 _augment(GF, _tmp)
 405
 406 class _tmp:
 407   def product(*arg):
 408     'product(ITERABLE) or product(I, ...) -> PRODUCT'
 409     return MPMul(*arg).done()
 410   product = staticmethod(product)
 411 _augment(MPMul, _tmp)
 412
 413 ###--------------------------------------------------------------------------
 414 ### Abstract fields.
 415
 416 class _tmp:
 417   def fromstring(str): return _checkend(Field.parse(str))
 418   fromstring = staticmethod(fromstring)
 419 _augment(Field, _tmp)
 420
 421 class _tmp:
 422   def __repr__(me): return '%s(%sL)' % (_clsname(me), me.p)
 423   def __hash__(me): return 0x114401de ^ hash(me.p)
 424   def _repr_pretty_(me, pp, cyclep):
 425     ind = _pp_bgroup_tyname(pp, me)
 426     if cyclep: pp.text('...')
 427     else: pp.pretty(me.p)
 428     pp.end_group(ind, ')')
 429   def ec(me, a, b): return ECPrimeProjCurve(me, a, b)
 430 _augment(PrimeField, _tmp)
 431
 432 class _tmp:
 433   def __repr__(me): return '%s(%#xL)' % (_clsname(me), me.p)
 434   def ec(me, a, b): return ECBinProjCurve(me, a, b)
 435   def _repr_pretty_(me, pp, cyclep):
 436     ind = _pp_bgroup_tyname(pp, me)
 437     if cyclep: pp.text('...')
 438     else: pp.text('%#x' % me.p)
 439     pp.end_group(ind, ')')
 440 _augment(BinField, _tmp)
 441
 442 class _tmp:
 443   def __hash__(me): return 0x23e4701c ^ hash(me.p)
 444 _augment(BinPolyField, _tmp)
 445
 446 class _tmp:
 447   def __hash__(me):
 448     h = 0x9a7d6240
 449     h ^=   hash(me.p)
 450     h ^= 2*hash(me.beta) & 0xffffffff
 451     return h
 452 _augment(BinNormField, _tmp)
 453
 454 class _tmp:
 455   def __str__(me): return str(me.value)
 456   def __repr__(me): return '%s(%s)' % (repr(me.field), repr(me.value))
 457   _repr_pretty_ = _pp_str
 458 _augment(FE, _tmp)
 459
 460 ###--------------------------------------------------------------------------
 461 ### Elliptic curves.
 462
 463 class _tmp:
 464   def __repr__(me):
 465     return '%s(%r, %s, %s)' % (_clsname(me), me.field, me.a, me.b)
 466   def _repr_pretty_(me, pp, cyclep):
 467     ind = _pp_bgroup_tyname(pp, me)
 468     if cyclep:
 469       pp.text('...')
 470     else:
 471       pp.pretty(me.field); pp.text(','); pp.breakable()
 472       pp.pretty(me.a); pp.text(','); pp.breakable()
 473       pp.pretty(me.b)
 474     pp.end_group(ind, ')')
 475   def frombuf(me, s):
 476     return ecpt.frombuf(me, s)
 477   def fromraw(me, s):
 478     return ecpt.fromraw(me, s)
 479   def pt(me, *args):
 480     return me(*args)
 481 _augment(ECCurve, _tmp)
 482
 483 class _tmp:
 484   def __hash__(me):
 485     h = 0x6751d341
 486     h ^=   hash(me.field)
 487     h ^= 2*hash(me.a) ^ 0xffffffff
 488     h ^= 5*hash(me.b) ^ 0xffffffff
 489     return h
 490 _augment(ECPrimeCurve, _tmp)
 491
 492 class _tmp:
 493   def __hash__(me):
 494     h = 0x2ac203c5
 495     h ^=   hash(me.field)
 496     h ^= 2*hash(me.a) ^ 0xffffffff
 497     h ^= 5*hash(me.b) ^ 0xffffffff
 498     return h
 499 _augment(ECBinCurve, _tmp)
 500
 501 class _tmp:
 502   def __repr__(me):
 503     if not me: return '%s()' % _clsname(me)
 504     return '%s(%s, %s)' % (_clsname(me), me.ix, me.iy)
 505   def __str__(me):
 506     if not me: return 'inf'
 507     return '(%s, %s)' % (me.ix, me.iy)
 508   def _repr_pretty_(me, pp, cyclep):
 509     if cyclep:
 510       pp.text('...')
 511     elif not me:
 512       pp.text('inf')
 513     else:
 514       ind = _pp_bgroup(pp, '(')
 515       pp.pretty(me.ix); pp.text(','); pp.breakable()
 516       pp.pretty(me.iy)
 517       pp.end_group(ind, ')')
 518 _augment(ECPt, _tmp)
 519
 520 class _tmp:
 521   def __repr__(me):
 522     return '%s(curve = %r, G = %r, r = %s, h = %s)' % \
 523            (_clsname(me), me.curve, me.G, me.r, me.h)
 524   def _repr_pretty_(me, pp, cyclep):
 525     ind = _pp_bgroup_tyname(pp, me)
 526     if cyclep:
 527       pp.text('...')
 528     else:
 529       _pp_kv(pp, 'curve', me.curve); pp.text(','); pp.breakable()
 530       _pp_kv(pp, 'G', me.G); pp.text(','); pp.breakable()
 531       _pp_kv(pp, 'r', me.r); pp.text(','); pp.breakable()
 532       _pp_kv(pp, 'h', me.h)
 533     pp.end_group(ind, ')')
 534   def __hash__(me):
 535     h = 0x9bedb8de
 536     h ^=   hash(me.curve)
 537     h ^= 2*hash(me.G) & 0xffffffff
 538     return h
 539   def group(me):
 540     return ECGroup(me)
 541 _augment(ECInfo, _tmp)
 542
 543 class _tmp:
 544   def __repr__(me):
 545     if not me: return '%r()' % (me.curve)
 546     return '%r(%s, %s)' % (me.curve, me.x, me.y)
 547   def __str__(me):
 548     if not me: return 'inf'
 549     return '(%s, %s)' % (me.x, me.y)
 550   def _repr_pretty_(me, pp, cyclep):
 551     if cyclep:
 552       pp.text('...')
 553     elif not me:
 554       pp.text('inf')
 555     else:
 556       ind = _pp_bgroup(pp, '(')
 557       pp.pretty(me.x); pp.text(','); pp.breakable()
 558       pp.pretty(me.y)
 559       pp.end_group(ind, ')')
 560 _augment(ECPtCurve, _tmp)
 561
 562 ###--------------------------------------------------------------------------
 563 ### Key sizes.
 564
 565 class _tmp:
 566   def __repr__(me): return '%s(%d)' % (_clsname(me), me.default)
 567   def check(me, sz): return True
 568   def best(me, sz): return sz
 569 _augment(KeySZAny, _tmp)
 570
 571 class _tmp:
 572   def __repr__(me):
 573     return '%s(%d, %d, %d, %d)' % \
 574            (_clsname(me), me.default, me.min, me.max, me.mod)
 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       pp.pretty(me.min); pp.text(','); pp.breakable()
 582       pp.pretty(me.max); pp.text(','); pp.breakable()
 583       pp.pretty(me.mod)
 584     pp.end_group(ind, ')')
 585   def check(me, sz): return me.min <= sz <= me.max and sz % me.mod == 0
 586   def best(me, sz):
 587     if sz < me.min: raise ValueError, 'key too small'
 588     elif sz > me.max: return me.max
 589     else: return sz - (sz % me.mod)
 590 _augment(KeySZRange, _tmp)
 591
 592 class _tmp:
 593   def __repr__(me): return '%s(%d, %s)' % (_clsname(me), me.default, me.set)
 594   def _repr_pretty_(me, pp, cyclep):
 595     ind = _pp_bgroup_tyname(pp, me)
 596     if cyclep:
 597       pp.text('...')
 598     else:
 599       pp.pretty(me.default); pp.text(','); pp.breakable()
 600       ind1 = _pp_bgroup(pp, '{')
 601       _pp_commas(pp, pp.pretty, me.set)
 602       pp.end_group(ind1, '}')
 603     pp.end_group(ind, ')')
 604   def check(me, sz): return sz in me.set
 605   def best(me, sz):
 606     found = -1
 607     for i in me.set:
 608       if found < i <= sz: found = i
 609     if found < 0: raise ValueError, 'key too small'
 610     return found
 611 _augment(KeySZSet, _tmp)
 612
 613 ###--------------------------------------------------------------------------
 614 ### Key data objects.
 615
 616 class _tmp:
 617   def __repr__(me): return '%s(%r)' % (_clsname(me), me.name)
 618 _augment(KeyFile, _tmp)
 619
 620 class _tmp:
 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 me.iteritems()]))
 628   def _repr_pretty_(me, pp, cyclep):
 629     ind = _pp_bgroup_tyname(pp, me)
 630     if cyclep: pp.text('...')
 631     else: _pp_dict(pp, me.iteritems())
 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 _augment(KeyData, _tmp)
 651
 652 class _tmp:
 653   def _guts(me): return me.bin
 654 _augment(KeyDataBinary, _tmp)
 655
 656 class _tmp:
 657   def _guts(me): return me.ct
 658 _augment(KeyDataEncrypted, _tmp)
 659
 660 class _tmp:
 661   def _guts(me): return me.mp
 662 _augment(KeyDataMP, _tmp)
 663
 664 class _tmp:
 665   def _guts(me): return me.str
 666 _augment(KeyDataString, _tmp)
 667
 668 class _tmp:
 669   def _guts(me): return me.ecpt
 670 _augment(KeyDataECPt, _tmp)
 671
 672 class _tmp:
 673   def __repr__(me):
 674     return '%s({%s})' % (_clsname(me),
 675                          ', '.join(['%r: %r' % kv for kv in me.iteritems()]))
 676   def _repr_pretty_(me, pp, cyclep):
 677     ind = _pp_bgroup_tyname(pp, me, '({ ')
 678     if cyclep: pp.text('...')
 679     else: _pp_dict(pp, me.iteritems())
 680     pp.end_group(ind, ' })')
 681 _augment(KeyDataStructured, _tmp)
 682
 683 ###--------------------------------------------------------------------------
 684 ### Abstract groups.
 685
 686 class _tmp:
 687   def __repr__(me):
 688     return '%s(p = %s, r = %s, g = %s)' % (_clsname(me), me.p, me.r, me.g)
 689   def _repr_pretty_(me, pp, cyclep):
 690     ind = _pp_bgroup_tyname(pp, me)
 691     if cyclep:
 692       pp.text('...')
 693     else:
 694       _pp_kv(pp, 'p', me.p); pp.text(','); pp.breakable()
 695       _pp_kv(pp, 'r', me.r); pp.text(','); pp.breakable()
 696       _pp_kv(pp, 'g', me.g)
 697     pp.end_group(ind, ')')
 698 _augment(FGInfo, _tmp)
 699
 700 class _tmp:
 701   def group(me): return PrimeGroup(me)
 702 _augment(DHInfo, _tmp)
 703
 704 class _tmp:
 705   def group(me): return BinGroup(me)
 706 _augment(BinDHInfo, _tmp)
 707
 708 class _tmp:
 709   def __repr__(me):
 710     return '%s(%r)' % (_clsname(me), me.info)
 711   def _repr_pretty_(me, pp, cyclep):
 712     ind = _pp_bgroup_tyname(pp, me)
 713     if cyclep: pp.text('...')
 714     else: pp.pretty(me.info)
 715     pp.end_group(ind, ')')
 716 _augment(Group, _tmp)
 717
 718 class _tmp:
 719   def __hash__(me):
 720     info = me.info
 721     h = 0xbce3cfe6
 722     h ^=   hash(info.p)
 723     h ^= 2*hash(info.r) & 0xffffffff
 724     h ^= 5*hash(info.g) & 0xffffffff
 725     return h
 726   def _get_geval(me, x): return MP(x)
 727 _augment(PrimeGroup, _tmp)
 728
 729 class _tmp:
 730   def __hash__(me):
 731     info = me.info
 732     h = 0x80695949
 733     h ^=   hash(info.p)
 734     h ^= 2*hash(info.r) & 0xffffffff
 735     h ^= 5*hash(info.g) & 0xffffffff
 736     return h
 737   def _get_geval(me, x): return GF(x)
 738 _augment(BinGroup, _tmp)
 739
 740 class _tmp:
 741   def __hash__(me): return 0x0ec23dab ^ hash(me.info)
 742   def _get_geval(me, x): return x.toec()
 743 _augment(ECGroup, _tmp)
 744
 745 class _tmp:
 746   def __repr__(me):
 747     return '%r(%r)' % (me.group, str(me))
 748   def _repr_pretty_(me, pp, cyclep):
 749     pp.pretty(type(me)._get_geval(me))
 750 _augment(GE, _tmp)
 751
 752 ###--------------------------------------------------------------------------
 753 ### RSA encoding techniques.
 754
 755 class PKCS1Crypt (object):
 756   def __init__(me, ep = '', rng = rand):
 757     me.ep = ep
 758     me.rng = rng
 759   def encode(me, msg, nbits):
 760     return _base._p1crypt_encode(msg, nbits, me.ep, me.rng)
 761   def decode(me, ct, nbits):
 762     return _base._p1crypt_decode(ct, nbits, me.ep, me.rng)
 763
 764 class PKCS1Sig (object):
 765   def __init__(me, ep = '', rng = rand):
 766     me.ep = ep
 767     me.rng = rng
 768   def encode(me, msg, nbits):
 769     return _base._p1sig_encode(msg, nbits, me.ep, me.rng)
 770   def decode(me, msg, sig, nbits):
 771     return _base._p1sig_decode(msg, sig, nbits, me.ep, me.rng)
 772
 773 class OAEP (object):
 774   def __init__(me, mgf = sha_mgf, hash = sha, ep = '', rng = rand):
 775     me.mgf = mgf
 776     me.hash = hash
 777     me.ep = ep
 778     me.rng = rng
 779   def encode(me, msg, nbits):
 780     return _base._oaep_encode(msg, nbits, me.mgf, me.hash, me.ep, me.rng)
 781   def decode(me, ct, nbits):
 782     return _base._oaep_decode(ct, nbits, me.mgf, me.hash, me.ep, me.rng)
 783
 784 class PSS (object):
 785   def __init__(me, mgf = sha_mgf, hash = sha, saltsz = None, rng = rand):
 786     me.mgf = mgf
 787     me.hash = hash
 788     if saltsz is None:
 789       saltsz = hash.hashsz
 790     me.saltsz = saltsz
 791     me.rng = rng
 792   def encode(me, msg, nbits):
 793     return _base._pss_encode(msg, nbits, me.mgf, me.hash, me.saltsz, me.rng)
 794   def decode(me, msg, sig, nbits):
 795     return _base._pss_decode(msg, sig, nbits,
 796                              me.mgf, me.hash, me.saltsz, me.rng)
 797
 798 class _tmp:
 799   def encrypt(me, msg, enc):
 800     return me.pubop(enc.encode(msg, me.n.nbits))
 801   def verify(me, msg, sig, enc):
 802     if msg is None: return enc.decode(msg, me.pubop(sig), me.n.nbits)
 803     try:
 804       x = enc.decode(msg, me.pubop(sig), me.n.nbits)
 805       return x is None or x == msg
 806     except ValueError:
 807       return False
 808   def __repr__(me):
 809     return '%s(n = %r, e = %r)' % (_clsname(me), me.n, me.e)
 810   def _repr_pretty_(me, pp, cyclep):
 811     ind = _pp_bgroup_tyname(pp, me)
 812     if cyclep:
 813       pp.text('...')
 814     else:
 815       _pp_kv(pp, 'n', me.n); pp.text(','); pp.breakable()
 816       _pp_kv(pp, 'e', me.e)
 817     pp.end_group(ind, ')')
 818 _augment(RSAPub, _tmp)
 819
 820 class _tmp:
 821   def decrypt(me, ct, enc): return enc.decode(me.privop(ct), me.n.nbits)
 822   def sign(me, msg, enc): return me.privop(enc.encode(msg, me.n.nbits))
 823   def __repr__(me):
 824     return '%s(n = %r, e = %r, d = %s, ' \
 825       'p = %s, q = %s, dp = %s, dq = %s, q_inv = %s)' % \
 826       (_clsname(me), me.n, me.e,
 827        _repr_secret(me.d), _repr_secret(me.p), _repr_secret(me.q),
 828        _repr_secret(me.dp), _repr_secret(me.dq), _repr_secret(me.q_inv))
 829   def _repr_pretty_(me, pp, cyclep):
 830     ind = _pp_bgroup_tyname(pp, me)
 831     if cyclep:
 832       pp.text('...')
 833     else:
 834       _pp_kv(pp, 'n', me.n); pp.text(','); pp.breakable()
 835       _pp_kv(pp, 'e', me.e); pp.text(','); pp.breakable()
 836       _pp_kv(pp, 'd', me.d, secretp = True); pp.text(','); pp.breakable()
 837       _pp_kv(pp, 'p', me.p, secretp = True); pp.text(','); pp.breakable()
 838       _pp_kv(pp, 'q', me.q, secretp = True); pp.text(','); pp.breakable()
 839       _pp_kv(pp, 'dp', me.dp, secretp = True); pp.text(','); pp.breakable()
 840       _pp_kv(pp, 'dq', me.dq, secretp = True); pp.text(','); pp.breakable()
 841       _pp_kv(pp, 'q_inv', me.q_inv, secretp = True)
 842     pp.end_group(ind, ')')
 843 _augment(RSAPriv, _tmp)
 844
 845 ###--------------------------------------------------------------------------
 846 ### DSA and related schemes.
 847
 848 class _tmp:
 849   def __repr__(me): return '%s(G = %r, p = %r)' % (_clsname(me), me.G, me.p)
 850   def _repr_pretty_(me, pp, cyclep):
 851     ind = _pp_bgroup_tyname(pp, me)
 852     if cyclep:
 853       pp.text('...')
 854     else:
 855       _pp_kv(pp, 'G', me.G); pp.text(','); pp.breakable()
 856       _pp_kv(pp, 'p', me.p)
 857     pp.end_group(ind, ')')
 858 _augment(DSAPub, _tmp)
 859 _augment(KCDSAPub, _tmp)
 860
 861 class _tmp:
 862   def __repr__(me): return '%s(G = %r, u = %s, p = %r)' % \
 863       (_clsname(me), me.G, _repr_secret(me.u), me.p)
 864   def _repr_pretty_(me, pp, cyclep):
 865     ind = _pp_bgroup_tyname(pp, me)
 866     if cyclep:
 867       pp.text('...')
 868     else:
 869       _pp_kv(pp, 'G', me.G); pp.text(','); pp.breakable()
 870       _pp_kv(pp, 'u', me.u, True); pp.text(','); pp.breakable()
 871       _pp_kv(pp, 'p', me.p)
 872     pp.end_group(ind, ')')
 873 _augment(DSAPriv, _tmp)
 874 _augment(KCDSAPriv, _tmp)
 875
 876 ###--------------------------------------------------------------------------
 877 ### Bernstein's elliptic curve crypto and related schemes.
 878
 879 X25519_BASE = MP(9).storel(32)
 880 X448_BASE = MP(5).storel(56)
 881
 882 Z128 = ByteString.zero(16)
 883
 884 class _BasePub (object):
 885   def __init__(me, pub, *args, **kw):
 886     if not me._PUBSZ.check(len(pub)): raise ValueError, 'bad public key'
 887     super(_BasePub, me).__init__(*args, **kw)
 888     me.pub = pub
 889   def __repr__(me): return '%s(pub = %r)' % (_clsname(me), me.pub)
 890   def _pp(me, pp): _pp_kv(pp, 'pub', me.pub)
 891   def _repr_pretty_(me, pp, cyclep):
 892     ind = _pp_bgroup_tyname(pp, me)
 893     if cyclep: pp.text('...')
 894     else: me._pp(pp)
 895     pp.end_group(ind, ')')
 896
 897 class _BasePriv (object):
 898   def __init__(me, priv, pub = None, *args, **kw):
 899     if not me._KEYSZ.check(len(priv)): raise ValueError, 'bad private key'
 900     if pub is None: pub = me._pubkey(priv)
 901     super(_BasePriv, me).__init__(pub = pub, *args, **kw)
 902     me.priv = priv
 903   @classmethod
 904   def generate(cls, rng = rand):
 905     return cls(rng.block(cls._KEYSZ.default))
 906   def __repr__(me):
 907     return '%s(priv = %d, pub = %r)' % \
 908         (_clsname(me), _repr_secret(me.priv), me.pub)
 909   def _pp(me, pp):
 910     _pp_kv(pp, 'priv', me.priv, secretp = True); pp.text(','); pp.breakable()
 911     super(_BasePriv, me)._pp(pp)
 912
 913 class _XDHPub (_BasePub):  pass
 914
 915 class _XDHPriv (_BasePriv):
 916   def _pubkey(me, priv): return me._op(priv, me._BASE)
 917   def agree(me, you): return me._op(me.priv, you.pub)
 918   def boxkey(me, recip): return me._hashkey(me.agree(recip))
 919   def box(me, recip, n, m): return secret_box(me.boxkey(recip), n, m)
 920   def unbox(me, recip, n, c): return secret_unbox(me.boxkey(recip), n, c)
 921
 922 class X25519Pub (_XDHPub):
 923   _PUBSZ = KeySZSet(X25519_PUBSZ)
 924   _BASE = X25519_BASE
 925
 926 class X25519Priv (_XDHPriv, X25519Pub):
 927   _KEYSZ = KeySZSet(X25519_KEYSZ)
 928   def _op(me, k, X): return x25519(k, X)
 929   def _hashkey(me, z): return hsalsa20_prf(z, Z128)
 930
 931 class X448Pub (_XDHPub):
 932   _PUBSZ = KeySZSet(X448_PUBSZ)
 933   _BASE = X448_BASE
 934
 935 class X448Priv (_XDHPriv, X448Pub):
 936   _KEYSZ = KeySZSet(X448_KEYSZ)
 937   def _op(me, k, X): return x448(k, X)
 938   def _hashkey(me, z): return Shake256().hash(z).done(salsa20.keysz.default)
 939
 940 class _EdDSAPub (_BasePub):
 941   def beginhash(me): return me._HASH()
 942   def endhash(me, h): return h.done()
 943
 944 class _EdDSAPriv (_BasePriv, _EdDSAPub):
 945   pass
 946
 947 class Ed25519Pub (_EdDSAPub):
 948   _PUBSZ = KeySZSet(ED25519_PUBSZ)
 949   _HASH = sha512
 950   def verify(me, msg, sig, **kw):
 951     return ed25519_verify(me.pub, msg, sig, **kw)
 952
 953 class Ed25519Priv (_EdDSAPriv, Ed25519Pub):
 954   _KEYSZ = KeySZAny(ED25519_KEYSZ)
 955   def _pubkey(me, priv): return ed25519_pubkey(priv)
 956   def sign(me, msg, **kw):
 957     return ed25519_sign(me.priv, msg, pub = me.pub, **kw)
 958
 959 class Ed448Pub (_EdDSAPub):
 960   _PUBSZ = KeySZSet(ED448_PUBSZ)
 961   _HASH = shake256
 962   def verify(me, msg, sig, **kw):
 963     return ed448_verify(me.pub, msg, sig, **kw)
 964
 965 class Ed448Priv (_EdDSAPriv, Ed448Pub):
 966   _KEYSZ = KeySZAny(ED448_KEYSZ)
 967   def _pubkey(me, priv): return ed448_pubkey(priv)
 968   def sign(me, msg, **kw):
 969     return ed448_sign(me.priv, msg, pub = me.pub, **kw)
 970
 971 ###--------------------------------------------------------------------------
 972 ### Built-in named curves and prime groups.
 973
 974 class _groupmap (object):
 975   def __init__(me, map, nth):
 976     me.map = map
 977     me.nth = nth
 978     me._n = max(map.values()) + 1
 979     me.i = me._n*[None]
 980   def __repr__(me):
 981     return '{%s}' % ', '.join(['%r: %r' % kv for kv in me.iteritems()])
 982   def _repr_pretty_(me, pp, cyclep):
 983     ind = _pp_bgroup(pp, '{ ')
 984     if cyclep: pp.text('...')
 985     else: _pp_dict(pp, me.iteritems())
 986     pp.end_group(ind, ' }')
 987   def __len__(me):
 988     return me._n
 989   def __contains__(me, k):
 990     return k in me.map
 991   def __getitem__(me, k):
 992     i = me.map[k]
 993     if me.i[i] is None:
 994       me.i[i] = me.nth(i)
 995     return me.i[i]
 996   def __setitem__(me, k, v):
 997     raise TypeError, "immutable object"
 998   def __iter__(me):
 999     return iter(me.map)
1000   def iterkeys(me):
1001     return iter(me.map)
1002   def itervalues(me):
1003     for k in me:
1004       yield me[k]
1005   def iteritems(me):
1006     for k in me:
1007       yield k, me[k]
1008   def keys(me):
1009     return [k for k in me]
1010   def values(me):
1011     return [me[k] for k in me]
1012   def items(me):
1013     return [(k, me[k]) for k in me]
1014 eccurves = _groupmap(_base._eccurves, ECInfo._curven)
1015 primegroups = _groupmap(_base._pgroups, DHInfo._groupn)
1016 bingroups = _groupmap(_base._bingroups, BinDHInfo._groupn)
1017
1018 ###--------------------------------------------------------------------------
1019 ### Prime number generation.
1020
1021 class PrimeGenEventHandler (object):
1022   def pg_begin(me, ev):
1023     return me.pg_try(ev)
1024   def pg_done(me, ev):
1025     return PGEN_DONE
1026   def pg_abort(me, ev):
1027     return PGEN_TRY
1028   def pg_fail(me, ev):
1029     return PGEN_TRY
1030   def pg_pass(me, ev):
1031     return PGEN_TRY
1032
1033 class SophieGermainStepJump (object):
1034   def pg_begin(me, ev):
1035     me.lf = PrimeFilter(ev.x)
1036     me.hf = me.lf.muladd(2, 1)
1037     return me.cont(ev)
1038   def pg_try(me, ev):
1039     me.step()
1040     return me.cont(ev)
1041   def cont(me, ev):
1042     while me.lf.status == PGEN_FAIL or me.hf.status == PGEN_FAIL:
1043       me.step()
1044     if me.lf.status == PGEN_ABORT or me.hf.status == PGEN_ABORT:
1045       return PGEN_ABORT
1046     ev.x = me.lf.x
1047     if me.lf.status == PGEN_DONE and me.hf.status == PGEN_DONE:
1048       return PGEN_DONE
1049     return PGEN_TRY
1050   def pg_done(me, ev):
1051     del me.lf
1052     del me.hf
1053
1054 class SophieGermainStepper (SophieGermainStepJump):
1055   def __init__(me, step):
1056     me.lstep = step;
1057     me.hstep = 2 * step
1058   def step(me):
1059     me.lf.step(me.lstep)
1060     me.hf.step(me.hstep)
1061
1062 class SophieGermainJumper (SophieGermainStepJump):
1063   def __init__(me, jump):
1064     me.ljump = PrimeFilter(jump);
1065     me.hjump = me.ljump.muladd(2, 0)
1066   def step(me):
1067     me.lf.jump(me.ljump)
1068     me.hf.jump(me.hjump)
1069   def pg_done(me, ev):
1070     del me.ljump
1071     del me.hjump
1072     SophieGermainStepJump.pg_done(me, ev)
1073
1074 class SophieGermainTester (object):
1075   def __init__(me):
1076     pass
1077   def pg_begin(me, ev):
1078     me.lr = RabinMiller(ev.x)
1079     me.hr = RabinMiller(2 * ev.x + 1)
1080   def pg_try(me, ev):
1081     lst = me.lr.test(ev.rng.range(me.lr.x))
1082     if lst != PGEN_PASS and lst != PGEN_DONE:
1083       return lst
1084     rst = me.hr.test(ev.rng.range(me.hr.x))
1085     if rst != PGEN_PASS and rst != PGEN_DONE:
1086       return rst
1087     if lst == PGEN_DONE and rst == PGEN_DONE:
1088       return PGEN_DONE
1089     return PGEN_PASS
1090   def pg_done(me, ev):
1091     del me.lr
1092     del me.hr
1093
1094 class PrimitiveStepper (PrimeGenEventHandler):
1095   def __init__(me):
1096     pass
1097   def pg_try(me, ev):
1098     ev.x = me.i.next()
1099     return PGEN_TRY
1100   def pg_begin(me, ev):
1101     me.i = iter(smallprimes)
1102     return me.pg_try(ev)
1103
1104 class PrimitiveTester (PrimeGenEventHandler):
1105   def __init__(me, mod, hh = [], exp = None):
1106     me.mod = MPMont(mod)
1107     me.exp = exp
1108     me.hh = hh
1109   def pg_try(me, ev):
1110     x = ev.x
1111     if me.exp is not None:
1112       x = me.mod.exp(x, me.exp)
1113       if x == 1: return PGEN_FAIL
1114     for h in me.hh:
1115       if me.mod.exp(x, h) == 1: return PGEN_FAIL
1116     ev.x = x
1117     return PGEN_DONE
1118
1119 class SimulStepper (PrimeGenEventHandler):
1120   def __init__(me, mul = 2, add = 1, step = 2):
1121     me.step = step
1122     me.mul = mul
1123     me.add = add
1124   def _stepfn(me, step):
1125     if step <= 0:
1126       raise ValueError, 'step must be positive'
1127     if step <= MPW_MAX:
1128       return lambda f: f.step(step)
1129     j = PrimeFilter(step)
1130     return lambda f: f.jump(j)
1131   def pg_begin(me, ev):
1132     x = ev.x
1133     me.lf = PrimeFilter(x)
1134     me.hf = PrimeFilter(x * me.mul + me.add)
1135     me.lstep = me._stepfn(me.step)
1136     me.hstep = me._stepfn(me.step * me.mul)
1137     SimulStepper._cont(me, ev)
1138   def pg_try(me, ev):
1139     me._step()
1140     me._cont(ev)
1141   def _step(me):
1142     me.lstep(me.lf)
1143     me.hstep(me.hf)
1144   def _cont(me, ev):
1145     while me.lf.status == PGEN_FAIL or me.hf.status == PGEN_FAIL:
1146       me._step()
1147     if me.lf.status == PGEN_ABORT or me.hf.status == PGEN_ABORT:
1148       return PGEN_ABORT
1149     ev.x = me.lf.x
1150     if me.lf.status == PGEN_DONE and me.hf.status == PGEN_DONE:
1151       return PGEN_DONE
1152     return PGEN_TRY
1153   def pg_done(me, ev):
1154     del me.lf
1155     del me.hf
1156     del me.lstep
1157     del me.hstep
1158
1159 class SimulTester (PrimeGenEventHandler):
1160   def __init__(me, mul = 2, add = 1):
1161     me.mul = mul
1162     me.add = add
1163   def pg_begin(me, ev):
1164     x = ev.x
1165     me.lr = RabinMiller(x)
1166     me.hr = RabinMiller(x * me.mul + me.add)
1167   def pg_try(me, ev):
1168     lst = me.lr.test(ev.rng.range(me.lr.x))
1169     if lst != PGEN_PASS and lst != PGEN_DONE:
1170       return lst
1171     rst = me.hr.test(ev.rng.range(me.hr.x))
1172     if rst != PGEN_PASS and rst != PGEN_DONE:
1173       return rst
1174     if lst == PGEN_DONE and rst == PGEN_DONE:
1175       return PGEN_DONE
1176     return PGEN_PASS
1177   def pg_done(me, ev):
1178     del me.lr
1179     del me.hr
1180
1181 def sgprime(start, step = 2, name = 'p', event = pgen_nullev, nsteps = 0):
1182   start = MP(start)
1183   return pgen(start, name, SimulStepper(step = step), SimulTester(), event,
1184               nsteps, RabinMiller.iters(start.nbits))
1185
1186 def findprimitive(mod, hh = [], exp = None, name = 'g', event = pgen_nullev):
1187   return pgen(0, name, PrimitiveStepper(), PrimitiveTester(mod, hh, exp),
1188               event, 0, 1)
1189
1190 def kcdsaprime(pbits, qbits, rng = rand,
1191                event = pgen_nullev, name = 'p', nsteps = 0):
1192   hbits = pbits - qbits
1193   h = pgen(rng.mp(hbits, 1), name + ' [h]',
1194            PrimeGenStepper(2), PrimeGenTester(),
1195            event, nsteps, RabinMiller.iters(hbits))
1196   q = pgen(rng.mp(qbits, 1), name, SimulStepper(2 * h, 1, 2),
1197            SimulTester(2 * h, 1), event, nsteps, RabinMiller.iters(qbits))
1198   p = 2 * q * h + 1
1199   return p, q, h
1200
1201 #----- That's all, folks ----------------------------------------------------