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 import _base
  27 import types as _types
  28 from binascii import hexlify as _hexify, unhexlify as _unhexify
  29 from sys import argv as _argv
  30
  31 ###--------------------------------------------------------------------------
  32 ### Basic stuff.
  33
  34 ## For the benefit of the default keyreporter, we need the program na,e.
  35 _base._ego(_argv[0])
  36
  37 ## Initialize the module.  Drag in the static methods of the various
  38 ## classes; create names for the various known crypto algorithms.
  39 def _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',
  46             'ECPt', 'ECPtCurve', 'ECCurve', 'ECInfo',
  47             'DHInfo', 'BinDHInfo', 'RSAPriv', 'BBSPriv',
  48             'PrimeFilter', 'RabinMiller',
  49             'Group', 'GE',
  50             'KeySZ', 'KeyData']:
  51     c = d[i]
  52     pre = '_' + i + '_'
  53     plen = len(pre)
  54     for j in b:
  55       if j[:plen] == pre:
  56         setattr(c, j[plen:], classmethod(b[j]))
  57   for i in [gcciphers, gchashes, gcmacs, gcprps]:
  58     for c in i.itervalues():
  59       d[c.name.replace('-', '_').translate(None, '/')] = c
  60   for c in gccrands.itervalues():
  61     d[c.name.replace('-', '_').translate(None, '/') + 'rand'] = c
  62 _init()
  63
  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.
  67 def _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
  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.
  79 def _checkend(r):
  80   x, rest = r
  81   if rest != '':
  82     raise SyntaxError, 'junk at end of string'
  83   return x
  84
  85 ## Some pretty-printing utilities.
  86 def _pp_str(me, pp, cyclep): pp.text(cyclep and '...' or str(me))
  87 def _pp_bgroup(pp, text):
  88   ind = len(text)
  89   pp.begin_group(ind, text)
  90   return ind
  91 def _pp_bgroup_tyname(pp, obj, open = '('):
  92   return _pp_bgroup(pp, type(obj).__name__ + open)
  93 def _pp_kv(pp, k, v):
  94   ind = _pp_bgroup(pp, k + ' = ')
  95   pp.pretty(v)
  96   pp.end_group(ind, '')
  97 def _pp_commas(pp, printfn, items):
  98   firstp = True
  99   for i in items:
 100     if firstp: firstp = False
 101     else: pp.text(','); pp.breakable()
 102     printfn(i)
 103 def _pp_dict(pp, items):
 104   def p((k, v)):
 105     pp.begin_group(0)
 106     pp.pretty(k)
 107     pp.text(':')
 108     pp.begin_group(2)
 109     pp.breakable()
 110     pp.pretty(v)
 111     pp.end_group(2)
 112     pp.end_group(0)
 113   _pp_commas(pp, p, items)
 114
 115 ###--------------------------------------------------------------------------
 116 ### Bytestrings.
 117
 118 class _tmp:
 119   def fromhex(x):
 120     return ByteString(_unhexify(x))
 121   fromhex = staticmethod(fromhex)
 122   def __hex__(me):
 123     return _hexify(me)
 124   def __repr__(me):
 125     return 'bytes(%r)' % hex(me)
 126 _augment(ByteString, _tmp)
 127 ByteString.__hash__ = str.__hash__
 128 bytes = ByteString.fromhex
 129
 130 ###--------------------------------------------------------------------------
 131 ### Hashing.
 132
 133 class _tmp:
 134   def check(me, h):
 135     hh = me.done()
 136     return ctstreq(h, hh)
 137 _augment(GHash, _tmp)
 138 _augment(Poly1305Hash, _tmp)
 139
 140 ###--------------------------------------------------------------------------
 141 ### NaCl `secretbox'.
 142
 143 def secret_box(k, n, m):
 144   E = xsalsa20(k).setiv(n)
 145   r = E.enczero(poly1305.keysz.default)
 146   s = E.enczero(poly1305.masksz)
 147   y = E.encrypt(m)
 148   t = poly1305(r)(s).hash(y).done()
 149   return ByteString(t + y)
 150
 151 def secret_unbox(k, n, c):
 152   E = xsalsa20(k).setiv(n)
 153   r = E.enczero(poly1305.keysz.default)
 154   s = E.enczero(poly1305.masksz)
 155   y = c[poly1305.tagsz:]
 156   if not poly1305(r)(s).hash(y).check(c[0:poly1305.tagsz]):
 157     raise ValueError, 'decryption failed'
 158   return E.decrypt(c[poly1305.tagsz:])
 159
 160 ###--------------------------------------------------------------------------
 161 ### Multiprecision integers and binary polynomials.
 162
 163 def _split_rat(x):
 164   if isinstance(x, BaseRat): return x._n, x._d
 165   else: return x, 1
 166 class BaseRat (object):
 167   """Base class implementing fields of fractions over Euclidean domains."""
 168   def __new__(cls, a, b):
 169     a, b = cls.RING(a), cls.RING(b)
 170     q, r = divmod(a, b)
 171     if r == 0: return q
 172     g = b.gcd(r)
 173     me = super(BaseRat, cls).__new__(cls)
 174     me._n = a//g
 175     me._d = b//g
 176     return me
 177   @property
 178   def numer(me): return me._n
 179   @property
 180   def denom(me): return me._d
 181   def __str__(me): return '%s/%s' % (me._n, me._d)
 182   def __repr__(me): return '%s(%s, %s)' % (type(me).__name__, me._n, me._d)
 183   _repr_pretty_ = _pp_str
 184
 185   def __add__(me, you):
 186     n, d = _split_rat(you)
 187     return type(me)(me._n*d + n*me._d, d*me._d)
 188   __radd__ = __add__
 189   def __sub__(me, you):
 190     n, d = _split_rat(you)
 191     return type(me)(me._n*d - n*me._d, d*me._d)
 192   def __rsub__(me, you):
 193     n, d = _split_rat(you)
 194     return type(me)(n*me._d - me._n*d, d*me._d)
 195   def __mul__(me, you):
 196     n, d = _split_rat(you)
 197     return type(me)(me._n*n, me._d*d)
 198   def __div__(me, you):
 199     n, d = _split_rat(you)
 200     return type(me)(me._n*d, me._d*n)
 201   def __rdiv__(me, you):
 202     n, d = _split_rat(you)
 203     return type(me)(me._d*n, me._n*d)
 204   def __cmp__(me, you):
 205     n, d = _split_rat(you)
 206     return type(me)(me._n*d, n*me._d)
 207   def __rcmp__(me, you):
 208     n, d = _split_rat(you)
 209     return cmp(n*me._d, me._n*d)
 210
 211 class IntRat (BaseRat):
 212   RING = MP
 213
 214 class GFRat (BaseRat):
 215   RING = GF
 216
 217 class _tmp:
 218   def negp(x): return x < 0
 219   def posp(x): return x > 0
 220   def zerop(x): return x == 0
 221   def oddp(x): return x.testbit(0)
 222   def evenp(x): return not x.testbit(0)
 223   def mont(x): return MPMont(x)
 224   def barrett(x): return MPBarrett(x)
 225   def reduce(x): return MPReduce(x)
 226   def __div__(me, you): return IntRat(me, you)
 227   def __rdiv__(me, you): return IntRat(you, me)
 228   _repr_pretty_ = _pp_str
 229 _augment(MP, _tmp)
 230
 231 class _tmp:
 232   def zerop(x): return x == 0
 233   def reduce(x): return GFReduce(x)
 234   def trace(x, y): return x.reduce().trace(y)
 235   def halftrace(x, y): return x.reduce().halftrace(y)
 236   def modsqrt(x, y): return x.reduce().sqrt(y)
 237   def quadsolve(x, y): return x.reduce().quadsolve(y)
 238   def __div__(me, you): return GFRat(me, you)
 239   def __rdiv__(me, you): return GFRat(you, me)
 240   _repr_pretty_ = _pp_str
 241 _augment(GF, _tmp)
 242
 243 class _tmp:
 244   def product(*arg):
 245     'product(ITERABLE) or product(I, ...) -> PRODUCT'
 246     return MPMul(*arg).done()
 247   product = staticmethod(product)
 248 _augment(MPMul, _tmp)
 249
 250 ###--------------------------------------------------------------------------
 251 ### Abstract fields.
 252
 253 class _tmp:
 254   def fromstring(str): return _checkend(Field.parse(str))
 255   fromstring = staticmethod(fromstring)
 256 _augment(Field, _tmp)
 257
 258 class _tmp:
 259   def __repr__(me): return '%s(%sL)' % (type(me).__name__, me.p)
 260   def __hash__(me): return 0x114401de ^ hash(me.p)
 261   def _repr_pretty_(me, pp, cyclep):
 262     ind = _pp_bgroup_tyname(pp, me)
 263     if cyclep: pp.text('...')
 264     else: pp.pretty(me.p)
 265     pp.end_group(ind, ')')
 266   def ec(me, a, b): return ECPrimeProjCurve(me, a, b)
 267 _augment(PrimeField, _tmp)
 268
 269 class _tmp:
 270   def __repr__(me): return '%s(%#xL)' % (type(me).__name__, me.p)
 271   def ec(me, a, b): return ECBinProjCurve(me, a, b)
 272   def _repr_pretty_(me, pp, cyclep):
 273     ind = _pp_bgroup_tyname(pp, me)
 274     if cyclep: pp.text('...')
 275     else: pp.text('%#x' % me.p)
 276     pp.end_group(ind, ')')
 277 _augment(BinField, _tmp)
 278
 279 class _tmp:
 280   def __hash__(me): return 0x23e4701c ^ hash(me.p)
 281 _augment(BinPolyField, _tmp)
 282
 283 class _tmp:
 284   def __hash__(me):
 285     h = 0x9a7d6240
 286     h ^=   hash(me.p)
 287     h ^= 2*hash(me.beta) & 0xffffffff
 288     return h
 289 _augment(BinNormField, _tmp)
 290
 291 class _tmp:
 292   def __str__(me): return str(me.value)
 293   def __repr__(me): return '%s(%s)' % (repr(me.field), repr(me.value))
 294   _repr_pretty_ = _pp_str
 295 _augment(FE, _tmp)
 296
 297 ###--------------------------------------------------------------------------
 298 ### Elliptic curves.
 299
 300 class _tmp:
 301   def __repr__(me):
 302     return '%s(%r, %s, %s)' % (type(me).__name__, me.field, me.a, me.b)
 303   def _repr_pretty_(me, pp, cyclep):
 304     ind = _pp_bgroup_tyname(pp, me)
 305     if cyclep:
 306       pp.text('...')
 307     else:
 308       pp.pretty(me.field); pp.text(','); pp.breakable()
 309       pp.pretty(me.a); pp.text(','); pp.breakable()
 310       pp.pretty(me.b)
 311     pp.end_group(ind, ')')
 312   def frombuf(me, s):
 313     return ecpt.frombuf(me, s)
 314   def fromraw(me, s):
 315     return ecpt.fromraw(me, s)
 316   def pt(me, *args):
 317     return me(*args)
 318 _augment(ECCurve, _tmp)
 319
 320 class _tmp:
 321   def __hash__(me):
 322     h = 0x6751d341
 323     h ^=   hash(me.field)
 324     h ^= 2*hash(me.a) ^ 0xffffffff
 325     h ^= 5*hash(me.b) ^ 0xffffffff
 326     return h
 327 _augment(ECPrimeCurve, _tmp)
 328
 329 class _tmp:
 330   def __hash__(me):
 331     h = 0x2ac203c5
 332     h ^=   hash(me.field)
 333     h ^= 2*hash(me.a) ^ 0xffffffff
 334     h ^= 5*hash(me.b) ^ 0xffffffff
 335     return h
 336 _augment(ECBinCurve, _tmp)
 337
 338 class _tmp:
 339   def __repr__(me):
 340     if not me: return 'ECPt()'
 341     return 'ECPt(%s, %s)' % (me.ix, me.iy)
 342   def __str__(me):
 343     if not me: return 'inf'
 344     return '(%s, %s)' % (me.ix, me.iy)
 345   def _repr_pretty_(me, pp, cyclep):
 346     if cyclep:
 347       pp.text('...')
 348     elif not me:
 349       pp.text('inf')
 350     else:
 351       ind = _pp_bgroup(pp, '(')
 352       pp.pretty(me.ix); pp.text(','); pp.breakable()
 353       pp.pretty(me.iy)
 354       pp.end_group(ind, ')')
 355 _augment(ECPt, _tmp)
 356
 357 class _tmp:
 358   def __repr__(me):
 359     return 'ECInfo(curve = %r, G = %r, r = %s, h = %s)' % \
 360            (me.curve, me.G, me.r, me.h)
 361   def _repr_pretty_(me, pp, cyclep):
 362     ind = _pp_bgroup_tyname(pp, me)
 363     if cyclep:
 364       pp.text('...')
 365     else:
 366       _pp_kv(pp, 'curve', me.curve); pp.text(','); pp.breakable()
 367       _pp_kv(pp, 'G', me.G); pp.text(','); pp.breakable()
 368       _pp_kv(pp, 'r', me.r); pp.text(','); pp.breakable()
 369       _pp_kv(pp, 'h', me.h)
 370     pp.end_group(ind, ')')
 371   def __hash__(me):
 372     h = 0x9bedb8de
 373     h ^=   hash(me.curve)
 374     h ^= 2*hash(me.G) & 0xffffffff
 375     return h
 376   def group(me):
 377     return ECGroup(me)
 378 _augment(ECInfo, _tmp)
 379
 380 class _tmp:
 381   def __repr__(me):
 382     if not me: return '%r()' % (me.curve)
 383     return '%r(%s, %s)' % (me.curve, me.x, me.y)
 384   def __str__(me):
 385     if not me: return 'inf'
 386     return '(%s, %s)' % (me.x, me.y)
 387 _augment(ECPtCurve, _tmp)
 388
 389 ###--------------------------------------------------------------------------
 390 ### Key sizes.
 391
 392 class _tmp:
 393   def __repr__(me): return 'KeySZAny(%d)' % me.default
 394   def check(me, sz): return True
 395   def best(me, sz): return sz
 396 _augment(KeySZAny, _tmp)
 397
 398 class _tmp:
 399   def __repr__(me):
 400     return 'KeySZRange(%d, %d, %d, %d)' % \
 401            (me.default, me.min, me.max, me.mod)
 402   def _repr_pretty_(me, pp, cyclep):
 403     ind = _pp_bgroup_tyname(pp, me)
 404     if cyclep:
 405       pp.text('...')
 406     else:
 407       pp.pretty(me.default); pp.text(','); pp.breakable()
 408       pp.pretty(me.min); pp.text(','); pp.breakable()
 409       pp.pretty(me.max); pp.text(','); pp.breakable()
 410       pp.pretty(me.mod)
 411     pp.end_group(ind, ')')
 412   def check(me, sz): return me.min <= sz <= me.max and sz % me.mod == 0
 413   def best(me, sz):
 414     if sz < me.min: raise ValueError, 'key too small'
 415     elif sz > me.max: return me.max
 416     else: return sz - (sz % me.mod)
 417 _augment(KeySZRange, _tmp)
 418
 419 class _tmp:
 420   def __repr__(me): return 'KeySZSet(%d, %s)' % (me.default, me.set)
 421   def _repr_pretty_(me, pp, cyclep):
 422     ind = _pp_bgroup_tyname(pp, me)
 423     if cyclep:
 424       pp.text('...')
 425     else:
 426       pp.pretty(me.default); pp.text(','); pp.breakable()
 427       ind1 = _pp_bgroup(pp, '{')
 428       _pp_commas(pp, pp.pretty, me.set)
 429       pp.end_group(ind1, '}')
 430     pp.end_group(ind, ')')
 431   def check(me, sz): return sz in me.set
 432   def best(me, sz):
 433     found = -1
 434     for i in me.set:
 435       if found < i <= sz: found = i
 436     if found < 0: raise ValueError, 'key too small'
 437     return found
 438 _augment(KeySZSet, _tmp)
 439
 440 ###--------------------------------------------------------------------------
 441 ### Key data objects.
 442
 443 class _tmp:
 444   def __repr__(me): return 'KeyFile(%r)' % me.name
 445 _augment(KeyFile, _tmp)
 446
 447 class _tmp:
 448   def __repr__(me): return 'Key(%r)' % me.fulltag
 449 _augment(Key, _tmp)
 450
 451 class _tmp:
 452   def __repr__(me):
 453     return 'KeyAttributes({%s})' % \
 454         ', '.join(['%r: %r' % kv for kv in me.iteritems()])
 455   def _repr_pretty_(me, pp, cyclep):
 456     ind = _pp_bgroup_tyname(pp, me)
 457     if cyclep: pp.text('...')
 458     else: _pp_dict(pp, me.iteritems())
 459     pp.end_group(ind, ')')
 460 _augment(KeyAttributes, _tmp)
 461
 462 class _tmp:
 463   def __repr__(me): return 'KeyDataBinary(%r, %r)' % \
 464         (me.bin, me.writeflags(me.flags))
 465   def _repr_pretty_(me, pp, cyclep):
 466     ind = _pp_bgroup_tyname(pp, me)
 467     if cyclep:
 468       pp.text('...')
 469     else:
 470       pp.pretty(me.bin); pp.text(','); pp.breakable()
 471       pp.pretty(me.writeflags(me.flags))
 472     pp.end_group(ind, ')')
 473 _augment(KeyDataBinary, _tmp)
 474
 475 class _tmp:
 476   def __repr__(me): return 'KeyDataEncrypted(%r, %r)' % \
 477         (me.ct, me.writeflags(me.flags))
 478   def _repr_pretty_(me, pp, cyclep):
 479     ind = _pp_bgroup_tyname(pp, me)
 480     if cyclep:
 481       pp.text('...')
 482     else:
 483       pp.pretty(me.ct); pp.text(','); pp.breakable()
 484       pp.pretty(me.writeflags(me.flags))
 485     pp.end_group(ind, ')')
 486 _augment(KeyDataEncrypted, _tmp)
 487
 488 class _tmp:
 489   def __repr__(me): return 'KeyDataMP(%r, %r)' % \
 490         (me.mp, me.writeflags(me.flags))
 491   def _repr_pretty_(me, pp, cyclep):
 492     ind = _pp_bgroup_tyname(pp, me)
 493     if cyclep:
 494       pp.text('...')
 495     else:
 496       pp.pretty(me.mp); pp.text(','); pp.breakable()
 497       pp.pretty(me.writeflags(me.flags))
 498     pp.end_group(ind, ')')
 499 _augment(KeyDataMP, _tmp)
 500
 501 class _tmp:
 502   def __repr__(me): return 'KeyDataString(%r)' % \
 503         (me.str, me.writeflags(me.flags))
 504   def _repr_pretty_(me, pp, cyclep):
 505     ind = _pp_bgroup_tyname(pp, me)
 506     if cyclep:
 507       pp.text('...')
 508     else:
 509       pp.pretty(me.str); pp.text(','); pp.breakable()
 510       pp.pretty(me.writeflags(me.flags))
 511     pp.end_group(ind, ')')
 512 _augment(KeyDataString, _tmp)
 513
 514 class _tmp:
 515   def __repr__(me): return 'KeyDataECPt(%r)' % \
 516         (me.ecpt, me.writeflags(me.flags))
 517   def _repr_pretty_(me, pp, cyclep):
 518     ind = _pp_bgroup_tyname(pp, me)
 519     if cyclep:
 520       pp.text('...')
 521     else:
 522       pp.pretty(me.ecpt); pp.text(','); pp.breakable()
 523       pp.pretty(me.writeflags(me.flags))
 524     pp.end_group(ind, ')')
 525 _augment(KeyDataECPt, _tmp)
 526
 527 class _tmp:
 528   def __repr__(me):
 529     return 'KeyDataStructured({%s})' % \
 530         ', '.join(['%r: %r' % kv for kv in me.iteritems()])
 531   def _repr_pretty_(me, pp, cyclep):
 532     ind = _pp_bgroup_tyname(pp, me, '({ ')
 533     if cyclep: pp.text('...')
 534     else: _pp_dict(pp, me.iteritems())
 535     pp.end_group(ind, ' })')
 536 _augment(KeyDataStructured, _tmp)
 537
 538 ###--------------------------------------------------------------------------
 539 ### Abstract groups.
 540
 541 class _tmp:
 542   def __repr__(me):
 543     return '%s(p = %s, r = %s, g = %s)' % \
 544            (type(me).__name__, me.p, me.r, me.g)
 545   def _repr_pretty_(me, pp, cyclep):
 546     ind = _pp_bgroup_tyname(pp, me)
 547     if cyclep:
 548       pp.text('...')
 549     else:
 550       _pp_kv(pp, 'p', me.p); pp.text(','); pp.breakable()
 551       _pp_kv(pp, 'r', me.r); pp.text(','); pp.breakable()
 552       _pp_kv(pp, 'g', me.g)
 553     pp.end_group(ind, ')')
 554 _augment(FGInfo, _tmp)
 555
 556 class _tmp:
 557   def group(me): return PrimeGroup(me)
 558 _augment(DHInfo, _tmp)
 559
 560 class _tmp:
 561   def group(me): return BinGroup(me)
 562 _augment(BinDHInfo, _tmp)
 563
 564 class _tmp:
 565   def __repr__(me):
 566     return '%s(%r)' % (type(me).__name__, me.info)
 567 _augment(Group, _tmp)
 568
 569 class _tmp:
 570   def __hash__(me):
 571     info = me.info
 572     h = 0xbce3cfe6
 573     h ^=   hash(info.p)
 574     h ^= 2*hash(info.r) & 0xffffffff
 575     h ^= 5*hash(info.g) & 0xffffffff
 576     return h
 577 _augment(PrimeGroup, _tmp)
 578
 579 class _tmp:
 580   def __hash__(me):
 581     info = me.info
 582     h = 0x80695949
 583     h ^=   hash(info.p)
 584     h ^= 2*hash(info.r) & 0xffffffff
 585     h ^= 5*hash(info.g) & 0xffffffff
 586     return h
 587 _augment(BinGroup, _tmp)
 588
 589 class _tmp:
 590   def __hash__(me): return 0x0ec23dab ^ hash(me.info)
 591 _augment(ECGroup, _tmp)
 592
 593 class _tmp:
 594   def __repr__(me):
 595     return '%r(%r)' % (me.group, str(me))
 596   _repr_pretty_ = _pp_str
 597 _augment(GE, _tmp)
 598
 599 ###--------------------------------------------------------------------------
 600 ### RSA encoding techniques.
 601
 602 class PKCS1Crypt (object):
 603   def __init__(me, ep = '', rng = rand):
 604     me.ep = ep
 605     me.rng = rng
 606   def encode(me, msg, nbits):
 607     return _base._p1crypt_encode(msg, nbits, me.ep, me.rng)
 608   def decode(me, ct, nbits):
 609     return _base._p1crypt_decode(ct, nbits, me.ep, me.rng)
 610
 611 class PKCS1Sig (object):
 612   def __init__(me, ep = '', rng = rand):
 613     me.ep = ep
 614     me.rng = rng
 615   def encode(me, msg, nbits):
 616     return _base._p1sig_encode(msg, nbits, me.ep, me.rng)
 617   def decode(me, msg, sig, nbits):
 618     return _base._p1sig_decode(msg, sig, nbits, me.ep, me.rng)
 619
 620 class OAEP (object):
 621   def __init__(me, mgf = sha_mgf, hash = sha, ep = '', rng = rand):
 622     me.mgf = mgf
 623     me.hash = hash
 624     me.ep = ep
 625     me.rng = rng
 626   def encode(me, msg, nbits):
 627     return _base._oaep_encode(msg, nbits, me.mgf, me.hash, me.ep, me.rng)
 628   def decode(me, ct, nbits):
 629     return _base._oaep_decode(ct, nbits, me.mgf, me.hash, me.ep, me.rng)
 630
 631 class PSS (object):
 632   def __init__(me, mgf = sha_mgf, hash = sha, saltsz = None, rng = rand):
 633     me.mgf = mgf
 634     me.hash = hash
 635     if saltsz is None:
 636       saltsz = hash.hashsz
 637     me.saltsz = saltsz
 638     me.rng = rng
 639   def encode(me, msg, nbits):
 640     return _base._pss_encode(msg, nbits, me.mgf, me.hash, me.saltsz, me.rng)
 641   def decode(me, msg, sig, nbits):
 642     return _base._pss_decode(msg, sig, nbits,
 643                              me.mgf, me.hash, me.saltsz, me.rng)
 644
 645 class _tmp:
 646   def encrypt(me, msg, enc):
 647     return me.pubop(enc.encode(msg, me.n.nbits))
 648   def verify(me, msg, sig, enc):
 649     if msg is None: return enc.decode(msg, me.pubop(sig), me.n.nbits)
 650     try:
 651       x = enc.decode(msg, me.pubop(sig), me.n.nbits)
 652       return x is None or x == msg
 653     except ValueError:
 654       return False
 655 _augment(RSAPub, _tmp)
 656
 657 class _tmp:
 658   def decrypt(me, ct, enc): return enc.decode(me.privop(ct), me.n.nbits)
 659   def sign(me, msg, enc): return me.privop(enc.encode(msg, me.n.nbits))
 660 _augment(RSAPriv, _tmp)
 661
 662 ###--------------------------------------------------------------------------
 663 ### Bernstein's elliptic curve crypto and related schemes.
 664
 665 X25519_BASE = \
 666   bytes('0900000000000000000000000000000000000000000000000000000000000000')
 667
 668 X448_BASE = \
 669   bytes('05000000000000000000000000000000000000000000000000000000'
 670         '00000000000000000000000000000000000000000000000000000000')
 671
 672 Z128 = bytes('00000000000000000000000000000000')
 673
 674 class _BoxyPub (object):
 675   def __init__(me, pub, *kw, **kwargs):
 676     if len(pub) != me._PUBSZ: raise ValueError, 'bad public key'
 677     super(_BoxyPub, me).__init__(*kw, **kwargs)
 678     me.pub = pub
 679
 680 class _BoxyPriv (_BoxyPub):
 681   def __init__(me, priv, pub = None, *kw, **kwargs):
 682     if len(priv) != me._KEYSZ: raise ValueError, 'bad private key'
 683     if pub is None: pub = me._op(priv, me._BASE)
 684     super(_BoxyPriv, me).__init__(pub = pub, *kw, **kwargs)
 685     me.priv = priv
 686   def agree(me, you): return me._op(me.priv, you.pub)
 687   def boxkey(me, recip):
 688     return me._hashkey(me.agree(recip))
 689   def box(me, recip, n, m):
 690     return secret_box(me.boxkey(recip), n, m)
 691   def unbox(me, recip, n, c):
 692     return secret_unbox(me.boxkey(recip, n, c))
 693
 694 class X25519Pub (_BoxyPub):
 695   _PUBSZ = X25519_PUBSZ
 696   _BASE = X25519_BASE
 697
 698 class X25519Priv (_BoxyPriv, X25519Pub):
 699   _KEYSZ = X25519_KEYSZ
 700   def _op(me, k, X): return x25519(k, X)
 701   def _hashkey(me, z): return hsalsa20_prf(z, Z128)
 702
 703 class X448Pub (_BoxyPub):
 704   _PUBSZ = X448_PUBSZ
 705   _BASE = X448_BASE
 706
 707 class X448Priv (_BoxyPriv, X448Pub):
 708   _KEYSZ = X448_KEYSZ
 709   def _op(me, k, X): return x448(k, X)
 710   ##def _hashkey(me, z): return ???
 711
 712 class Ed25519Pub (object):
 713   def __init__(me, pub):
 714     me.pub = pub
 715   def verify(me, msg, sig):
 716     return ed25519_verify(me.pub, msg, sig)
 717
 718 class Ed25519Priv (Ed25519Pub):
 719   def __init__(me, priv):
 720     me.priv = priv
 721     Ed25519Pub.__init__(me, ed25519_pubkey(priv))
 722   def sign(me, msg):
 723     return ed25519_sign(me.priv, msg, pub = me.pub)
 724   @classmethod
 725   def generate(cls, rng = rand):
 726     return cls(rng.block(ED25519_KEYSZ))
 727
 728 ###--------------------------------------------------------------------------
 729 ### Built-in named curves and prime groups.
 730
 731 class _groupmap (object):
 732   def __init__(me, map, nth):
 733     me.map = map
 734     me.nth = nth
 735     me._n = max(map.values()) + 1
 736     me.i = me._n*[None]
 737   def __repr__(me):
 738     return '{%s}' % ', '.join(['%r: %r' % kv for kv in me.iteritems()])
 739   def _repr_pretty_(me, pp, cyclep):
 740     ind = _pp_bgroup(pp, '{ ')
 741     if cyclep: pp.text('...')
 742     else: _pp_dict(pp, me.iteritems())
 743     pp.end_group(ind, ' }')
 744   def __len__(me):
 745     return me._n
 746   def __contains__(me, k):
 747     return k in me.map
 748   def __getitem__(me, k):
 749     i = me.map[k]
 750     if me.i[i] is None:
 751       me.i[i] = me.nth(i)
 752     return me.i[i]
 753   def __setitem__(me, k, v):
 754     raise TypeError, "immutable object"
 755   def __iter__(me):
 756     return iter(me.map)
 757   def iterkeys(me):
 758     return iter(me.map)
 759   def itervalues(me):
 760     for k in me:
 761       yield me[k]
 762   def iteritems(me):
 763     for k in me:
 764       yield k, me[k]
 765   def keys(me):
 766     return [k for k in me]
 767   def values(me):
 768     return [me[k] for k in me]
 769   def items(me):
 770     return [(k, me[k]) for k in me]
 771 eccurves = _groupmap(_base._eccurves, ECInfo._curven)
 772 primegroups = _groupmap(_base._pgroups, DHInfo._groupn)
 773 bingroups = _groupmap(_base._bingroups, BinDHInfo._groupn)
 774
 775 ###--------------------------------------------------------------------------
 776 ### Prime number generation.
 777
 778 class PrimeGenEventHandler (object):
 779   def pg_begin(me, ev):
 780     return me.pg_try(ev)
 781   def pg_done(me, ev):
 782     return PGEN_DONE
 783   def pg_abort(me, ev):
 784     return PGEN_TRY
 785   def pg_fail(me, ev):
 786     return PGEN_TRY
 787   def pg_pass(me, ev):
 788     return PGEN_TRY
 789
 790 class SophieGermainStepJump (object):
 791   def pg_begin(me, ev):
 792     me.lf = PrimeFilter(ev.x)
 793     me.hf = me.lf.muladd(2, 1)
 794     return me.cont(ev)
 795   def pg_try(me, ev):
 796     me.step()
 797     return me.cont(ev)
 798   def cont(me, ev):
 799     while me.lf.status == PGEN_FAIL or me.hf.status == PGEN_FAIL:
 800       me.step()
 801     if me.lf.status == PGEN_ABORT or me.hf.status == PGEN_ABORT:
 802       return PGEN_ABORT
 803     ev.x = me.lf.x
 804     if me.lf.status == PGEN_DONE and me.hf.status == PGEN_DONE:
 805       return PGEN_DONE
 806     return PGEN_TRY
 807   def pg_done(me, ev):
 808     del me.lf
 809     del me.hf
 810
 811 class SophieGermainStepper (SophieGermainStepJump):
 812   def __init__(me, step):
 813     me.lstep = step;
 814     me.hstep = 2 * step
 815   def step(me):
 816     me.lf.step(me.lstep)
 817     me.hf.step(me.hstep)
 818
 819 class SophieGermainJumper (SophieGermainStepJump):
 820   def __init__(me, jump):
 821     me.ljump = PrimeFilter(jump);
 822     me.hjump = me.ljump.muladd(2, 0)
 823   def step(me):
 824     me.lf.jump(me.ljump)
 825     me.hf.jump(me.hjump)
 826   def pg_done(me, ev):
 827     del me.ljump
 828     del me.hjump
 829     SophieGermainStepJump.pg_done(me, ev)
 830
 831 class SophieGermainTester (object):
 832   def __init__(me):
 833     pass
 834   def pg_begin(me, ev):
 835     me.lr = RabinMiller(ev.x)
 836     me.hr = RabinMiller(2 * ev.x + 1)
 837   def pg_try(me, ev):
 838     lst = me.lr.test(ev.rng.range(me.lr.x))
 839     if lst != PGEN_PASS and lst != PGEN_DONE:
 840       return lst
 841     rst = me.hr.test(ev.rng.range(me.hr.x))
 842     if rst != PGEN_PASS and rst != PGEN_DONE:
 843       return rst
 844     if lst == PGEN_DONE and rst == PGEN_DONE:
 845       return PGEN_DONE
 846     return PGEN_PASS
 847   def pg_done(me, ev):
 848     del me.lr
 849     del me.hr
 850
 851 class PrimitiveStepper (PrimeGenEventHandler):
 852   def __init__(me):
 853     pass
 854   def pg_try(me, ev):
 855     ev.x = me.i.next()
 856     return PGEN_TRY
 857   def pg_begin(me, ev):
 858     me.i = iter(smallprimes)
 859     return me.pg_try(ev)
 860
 861 class PrimitiveTester (PrimeGenEventHandler):
 862   def __init__(me, mod, hh = [], exp = None):
 863     me.mod = MPMont(mod)
 864     me.exp = exp
 865     me.hh = hh
 866   def pg_try(me, ev):
 867     x = ev.x
 868     if me.exp is not None:
 869       x = me.mod.exp(x, me.exp)
 870       if x == 1: return PGEN_FAIL
 871     for h in me.hh:
 872       if me.mod.exp(x, h) == 1: return PGEN_FAIL
 873     ev.x = x
 874     return PGEN_DONE
 875
 876 class SimulStepper (PrimeGenEventHandler):
 877   def __init__(me, mul = 2, add = 1, step = 2):
 878     me.step = step
 879     me.mul = mul
 880     me.add = add
 881   def _stepfn(me, step):
 882     if step <= 0:
 883       raise ValueError, 'step must be positive'
 884     if step <= MPW_MAX:
 885       return lambda f: f.step(step)
 886     j = PrimeFilter(step)
 887     return lambda f: f.jump(j)
 888   def pg_begin(me, ev):
 889     x = ev.x
 890     me.lf = PrimeFilter(x)
 891     me.hf = PrimeFilter(x * me.mul + me.add)
 892     me.lstep = me._stepfn(me.step)
 893     me.hstep = me._stepfn(me.step * me.mul)
 894     SimulStepper._cont(me, ev)
 895   def pg_try(me, ev):
 896     me._step()
 897     me._cont(ev)
 898   def _step(me):
 899     me.lstep(me.lf)
 900     me.hstep(me.hf)
 901   def _cont(me, ev):
 902     while me.lf.status == PGEN_FAIL or me.hf.status == PGEN_FAIL:
 903       me._step()
 904     if me.lf.status == PGEN_ABORT or me.hf.status == PGEN_ABORT:
 905       return PGEN_ABORT
 906     ev.x = me.lf.x
 907     if me.lf.status == PGEN_DONE and me.hf.status == PGEN_DONE:
 908       return PGEN_DONE
 909     return PGEN_TRY
 910   def pg_done(me, ev):
 911     del me.lf
 912     del me.hf
 913     del me.lstep
 914     del me.hstep
 915
 916 class SimulTester (PrimeGenEventHandler):
 917   def __init__(me, mul = 2, add = 1):
 918     me.mul = mul
 919     me.add = add
 920   def pg_begin(me, ev):
 921     x = ev.x
 922     me.lr = RabinMiller(x)
 923     me.hr = RabinMiller(x * me.mul + me.add)
 924   def pg_try(me, ev):
 925     lst = me.lr.test(ev.rng.range(me.lr.x))
 926     if lst != PGEN_PASS and lst != PGEN_DONE:
 927       return lst
 928     rst = me.hr.test(ev.rng.range(me.hr.x))
 929     if rst != PGEN_PASS and rst != PGEN_DONE:
 930       return rst
 931     if lst == PGEN_DONE and rst == PGEN_DONE:
 932       return PGEN_DONE
 933     return PGEN_PASS
 934   def pg_done(me, ev):
 935     del me.lr
 936     del me.hr
 937
 938 def sgprime(start, step = 2, name = 'p', event = pgen_nullev, nsteps = 0):
 939   start = MP(start)
 940   return pgen(start, name, SimulStepper(step = step), SimulTester(), event,
 941               nsteps, RabinMiller.iters(start.nbits))
 942
 943 def findprimitive(mod, hh = [], exp = None, name = 'g', event = pgen_nullev):
 944   return pgen(0, name, PrimitiveStepper(), PrimitiveTester(mod, hh, exp),
 945               event, 0, 1)
 946
 947 def kcdsaprime(pbits, qbits, rng = rand,
 948                event = pgen_nullev, name = 'p', nsteps = 0):
 949   hbits = pbits - qbits
 950   h = pgen(rng.mp(hbits, 1), name + ' [h]',
 951            PrimeGenStepper(2), PrimeGenTester(),
 952            event, nsteps, RabinMiller.iters(hbits))
 953   q = pgen(rng.mp(qbits, 1), name, SimulStepper(2 * h, 1, 2),
 954            SimulTester(2 * h, 1), event, nsteps, RabinMiller.iters(qbits))
 955   p = 2 * q * h + 1
 956   return p, q, h
 957
 958 #----- That's all, folks ----------------------------------------------------