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Diffstat (limited to 'lib/python2.7/base64.py')
-rwxr-xr-x | lib/python2.7/base64.py | 360 |
1 files changed, 0 insertions, 360 deletions
diff --git a/lib/python2.7/base64.py b/lib/python2.7/base64.py deleted file mode 100755 index 85204dd..0000000 --- a/lib/python2.7/base64.py +++ /dev/null @@ -1,360 +0,0 @@ -#! /usr/bin/env python - -"""RFC 3548: Base16, Base32, Base64 Data Encodings""" - -# Modified 04-Oct-1995 by Jack Jansen to use binascii module -# Modified 30-Dec-2003 by Barry Warsaw to add full RFC 3548 support - -import re -import struct -import binascii - - -__all__ = [ - # Legacy interface exports traditional RFC 1521 Base64 encodings - 'encode', 'decode', 'encodestring', 'decodestring', - # Generalized interface for other encodings - 'b64encode', 'b64decode', 'b32encode', 'b32decode', - 'b16encode', 'b16decode', - # Standard Base64 encoding - 'standard_b64encode', 'standard_b64decode', - # Some common Base64 alternatives. As referenced by RFC 3458, see thread - # starting at: - # - # http://zgp.org/pipermail/p2p-hackers/2001-September/000316.html - 'urlsafe_b64encode', 'urlsafe_b64decode', - ] - -_translation = [chr(_x) for _x in range(256)] -EMPTYSTRING = '' - - -def _translate(s, altchars): - translation = _translation[:] - for k, v in altchars.items(): - translation[ord(k)] = v - return s.translate(''.join(translation)) - - - -# Base64 encoding/decoding uses binascii - -def b64encode(s, altchars=None): - """Encode a string using Base64. - - s is the string to encode. Optional altchars must be a string of at least - length 2 (additional characters are ignored) which specifies an - alternative alphabet for the '+' and '/' characters. This allows an - application to e.g. generate url or filesystem safe Base64 strings. - - The encoded string is returned. - """ - # Strip off the trailing newline - encoded = binascii.b2a_base64(s)[:-1] - if altchars is not None: - return _translate(encoded, {'+': altchars[0], '/': altchars[1]}) - return encoded - - -def b64decode(s, altchars=None): - """Decode a Base64 encoded string. - - s is the string to decode. Optional altchars must be a string of at least - length 2 (additional characters are ignored) which specifies the - alternative alphabet used instead of the '+' and '/' characters. - - The decoded string is returned. A TypeError is raised if s were - incorrectly padded or if there are non-alphabet characters present in the - string. - """ - if altchars is not None: - s = _translate(s, {altchars[0]: '+', altchars[1]: '/'}) - try: - return binascii.a2b_base64(s) - except binascii.Error, msg: - # Transform this exception for consistency - raise TypeError(msg) - - -def standard_b64encode(s): - """Encode a string using the standard Base64 alphabet. - - s is the string to encode. The encoded string is returned. - """ - return b64encode(s) - -def standard_b64decode(s): - """Decode a string encoded with the standard Base64 alphabet. - - s is the string to decode. The decoded string is returned. A TypeError - is raised if the string is incorrectly padded or if there are non-alphabet - characters present in the string. - """ - return b64decode(s) - -def urlsafe_b64encode(s): - """Encode a string using a url-safe Base64 alphabet. - - s is the string to encode. The encoded string is returned. The alphabet - uses '-' instead of '+' and '_' instead of '/'. - """ - return b64encode(s, '-_') - -def urlsafe_b64decode(s): - """Decode a string encoded with the standard Base64 alphabet. - - s is the string to decode. The decoded string is returned. A TypeError - is raised if the string is incorrectly padded or if there are non-alphabet - characters present in the string. - - The alphabet uses '-' instead of '+' and '_' instead of '/'. - """ - return b64decode(s, '-_') - - - -# Base32 encoding/decoding must be done in Python -_b32alphabet = { - 0: 'A', 9: 'J', 18: 'S', 27: '3', - 1: 'B', 10: 'K', 19: 'T', 28: '4', - 2: 'C', 11: 'L', 20: 'U', 29: '5', - 3: 'D', 12: 'M', 21: 'V', 30: '6', - 4: 'E', 13: 'N', 22: 'W', 31: '7', - 5: 'F', 14: 'O', 23: 'X', - 6: 'G', 15: 'P', 24: 'Y', - 7: 'H', 16: 'Q', 25: 'Z', - 8: 'I', 17: 'R', 26: '2', - } - -_b32tab = _b32alphabet.items() -_b32tab.sort() -_b32tab = [v for k, v in _b32tab] -_b32rev = dict([(v, long(k)) for k, v in _b32alphabet.items()]) - - -def b32encode(s): - """Encode a string using Base32. - - s is the string to encode. The encoded string is returned. - """ - parts = [] - quanta, leftover = divmod(len(s), 5) - # Pad the last quantum with zero bits if necessary - if leftover: - s += ('\0' * (5 - leftover)) - quanta += 1 - for i in range(quanta): - # c1 and c2 are 16 bits wide, c3 is 8 bits wide. The intent of this - # code is to process the 40 bits in units of 5 bits. So we take the 1 - # leftover bit of c1 and tack it onto c2. Then we take the 2 leftover - # bits of c2 and tack them onto c3. The shifts and masks are intended - # to give us values of exactly 5 bits in width. - c1, c2, c3 = struct.unpack('!HHB', s[i*5:(i+1)*5]) - c2 += (c1 & 1) << 16 # 17 bits wide - c3 += (c2 & 3) << 8 # 10 bits wide - parts.extend([_b32tab[c1 >> 11], # bits 1 - 5 - _b32tab[(c1 >> 6) & 0x1f], # bits 6 - 10 - _b32tab[(c1 >> 1) & 0x1f], # bits 11 - 15 - _b32tab[c2 >> 12], # bits 16 - 20 (1 - 5) - _b32tab[(c2 >> 7) & 0x1f], # bits 21 - 25 (6 - 10) - _b32tab[(c2 >> 2) & 0x1f], # bits 26 - 30 (11 - 15) - _b32tab[c3 >> 5], # bits 31 - 35 (1 - 5) - _b32tab[c3 & 0x1f], # bits 36 - 40 (1 - 5) - ]) - encoded = EMPTYSTRING.join(parts) - # Adjust for any leftover partial quanta - if leftover == 1: - return encoded[:-6] + '======' - elif leftover == 2: - return encoded[:-4] + '====' - elif leftover == 3: - return encoded[:-3] + '===' - elif leftover == 4: - return encoded[:-1] + '=' - return encoded - - -def b32decode(s, casefold=False, map01=None): - """Decode a Base32 encoded string. - - s is the string to decode. Optional casefold is a flag specifying whether - a lowercase alphabet is acceptable as input. For security purposes, the - default is False. - - RFC 3548 allows for optional mapping of the digit 0 (zero) to the letter O - (oh), and for optional mapping of the digit 1 (one) to either the letter I - (eye) or letter L (el). The optional argument map01 when not None, - specifies which letter the digit 1 should be mapped to (when map01 is not - None, the digit 0 is always mapped to the letter O). For security - purposes the default is None, so that 0 and 1 are not allowed in the - input. - - The decoded string is returned. A TypeError is raised if s were - incorrectly padded or if there are non-alphabet characters present in the - string. - """ - quanta, leftover = divmod(len(s), 8) - if leftover: - raise TypeError('Incorrect padding') - # Handle section 2.4 zero and one mapping. The flag map01 will be either - # False, or the character to map the digit 1 (one) to. It should be - # either L (el) or I (eye). - if map01: - s = _translate(s, {'0': 'O', '1': map01}) - if casefold: - s = s.upper() - # Strip off pad characters from the right. We need to count the pad - # characters because this will tell us how many null bytes to remove from - # the end of the decoded string. - padchars = 0 - mo = re.search('(?P<pad>[=]*)$', s) - if mo: - padchars = len(mo.group('pad')) - if padchars > 0: - s = s[:-padchars] - # Now decode the full quanta - parts = [] - acc = 0 - shift = 35 - for c in s: - val = _b32rev.get(c) - if val is None: - raise TypeError('Non-base32 digit found') - acc += _b32rev[c] << shift - shift -= 5 - if shift < 0: - parts.append(binascii.unhexlify('%010x' % acc)) - acc = 0 - shift = 35 - # Process the last, partial quanta - last = binascii.unhexlify('%010x' % acc) - if padchars == 0: - last = '' # No characters - elif padchars == 1: - last = last[:-1] - elif padchars == 3: - last = last[:-2] - elif padchars == 4: - last = last[:-3] - elif padchars == 6: - last = last[:-4] - else: - raise TypeError('Incorrect padding') - parts.append(last) - return EMPTYSTRING.join(parts) - - - -# RFC 3548, Base 16 Alphabet specifies uppercase, but hexlify() returns -# lowercase. The RFC also recommends against accepting input case -# insensitively. -def b16encode(s): - """Encode a string using Base16. - - s is the string to encode. The encoded string is returned. - """ - return binascii.hexlify(s).upper() - - -def b16decode(s, casefold=False): - """Decode a Base16 encoded string. - - s is the string to decode. Optional casefold is a flag specifying whether - a lowercase alphabet is acceptable as input. For security purposes, the - default is False. - - The decoded string is returned. A TypeError is raised if s were - incorrectly padded or if there are non-alphabet characters present in the - string. - """ - if casefold: - s = s.upper() - if re.search('[^0-9A-F]', s): - raise TypeError('Non-base16 digit found') - return binascii.unhexlify(s) - - - -# Legacy interface. This code could be cleaned up since I don't believe -# binascii has any line length limitations. It just doesn't seem worth it -# though. - -MAXLINESIZE = 76 # Excluding the CRLF -MAXBINSIZE = (MAXLINESIZE//4)*3 - -def encode(input, output): - """Encode a file.""" - while True: - s = input.read(MAXBINSIZE) - if not s: - break - while len(s) < MAXBINSIZE: - ns = input.read(MAXBINSIZE-len(s)) - if not ns: - break - s += ns - line = binascii.b2a_base64(s) - output.write(line) - - -def decode(input, output): - """Decode a file.""" - while True: - line = input.readline() - if not line: - break - s = binascii.a2b_base64(line) - output.write(s) - - -def encodestring(s): - """Encode a string into multiple lines of base-64 data.""" - pieces = [] - for i in range(0, len(s), MAXBINSIZE): - chunk = s[i : i + MAXBINSIZE] - pieces.append(binascii.b2a_base64(chunk)) - return "".join(pieces) - - -def decodestring(s): - """Decode a string.""" - return binascii.a2b_base64(s) - - - -# Useable as a script... -def test(): - """Small test program""" - import sys, getopt - try: - opts, args = getopt.getopt(sys.argv[1:], 'deut') - except getopt.error, msg: - sys.stdout = sys.stderr - print msg - print """usage: %s [-d|-e|-u|-t] [file|-] - -d, -u: decode - -e: encode (default) - -t: encode and decode string 'Aladdin:open sesame'"""%sys.argv[0] - sys.exit(2) - func = encode - for o, a in opts: - if o == '-e': func = encode - if o == '-d': func = decode - if o == '-u': func = decode - if o == '-t': test1(); return - if args and args[0] != '-': - with open(args[0], 'rb') as f: - func(f, sys.stdout) - else: - func(sys.stdin, sys.stdout) - - -def test1(): - s0 = "Aladdin:open sesame" - s1 = encodestring(s0) - s2 = decodestring(s1) - print s0, repr(s1), s2 - - -if __name__ == '__main__': - test() |