diff --git a/lib/assets/Lib/base64.py b/lib/assets/Lib/base64.py new file mode 100644 --- /dev/null +++ b/lib/assets/Lib/base64.py @@ -0,0 +1,406 @@ +#! /usr/bin/env python3 + +"""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 +# Modified 22-May-2007 by Guido van Rossum to use bytes everywhere + +#import re +#import struct +#import binascii + +import _base64 # Javascript module in libs + +__all__ = [ + # Legacy interface exports traditional RFC 1521 Base64 encodings + 'encode', 'decode', 'encodebytes', 'decodebytes', + # 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', + ] + + +bytes_types = (bytes, bytearray) # Types acceptable as binary data + +def _bytes_from_decode_data(s): + if isinstance(s, str): + try: + return s.encode('ascii') + except UnicodeEncodeError: + raise ValueError('string argument should contain only ASCII characters') + elif isinstance(s, bytes_types): + return s + else: + raise TypeError("argument should be bytes or ASCII string, not %s" % s.__class__.__name__) + + + +# Base64 encoding/decoding uses binascii + +def b64encode(s, altchars=None): + """Encode a byte string using Base64. + + s is the byte string to encode. Optional altchars must be a byte + string of length 2 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 byte string is returned. + """ + if not isinstance(s, bytes_types): + raise TypeError("expected bytes, not %s" % s.__class__.__name__) + if altchars is not None: + if not isinstance(altchars, bytes_types): + print('wrong altchars') + raise TypeError("expected bytes, not %s" + % altchars.__class__.__name__) + assert len(altchars) >= 2, repr(altchars) + return _base64.Base64.encode(s, altchars) + + +def b64decode(s, altchars=None, validate=False): + """Decode a Base64 encoded byte string. + + s is the byte string to decode. Optional altchars must be a + string of length 2 which specifies the alternative alphabet used + instead of the '+' and '/' characters. + + The decoded string is returned. A binascii.Error is raised if s is + incorrectly padded. + + If validate is False (the default), non-base64-alphabet characters are + discarded prior to the padding check. If validate is True, + non-base64-alphabet characters in the input result in a binascii.Error. + """ + if altchars is not None: + altchars = _bytes_from_decode_data(altchars) + assert len(altchars) == 2, repr(altchars) + s = s.translate(bytes.maketrans(altchars, b'+/')) + return _base64.Base64.decode(s, altchars, validate) + + +def standard_b64encode(s): + """Encode a byte string using the standard Base64 alphabet. + + s is the byte string to encode. The encoded byte string is returned. + """ + return b64encode(s) + +def standard_b64decode(s): + """Decode a byte string encoded with the standard Base64 alphabet. + + s is the byte string to decode. The decoded byte string is + returned. binascii.Error is raised if the input is incorrectly + padded or if there are non-alphabet characters present in the + input. + """ + return b64decode(s) + + +_urlsafe_encode_translation = bytes.maketrans(b'+/', b'-_') +_urlsafe_decode_translation = bytes.maketrans(b'-_', b'+/') + +def urlsafe_b64encode(s): + """Encode a byte string using a url-safe Base64 alphabet. + + s is the byte string to encode. The encoded byte string is + returned. The alphabet uses '-' instead of '+' and '_' instead of + '/'. + """ + return b64encode(s).translate(_urlsafe_encode_translation) + +def urlsafe_b64decode(s): + """Decode a byte string encoded with the standard Base64 alphabet. + + s is the byte string to decode. The decoded byte string is + returned. binascii.Error is raised if the input is incorrectly + padded or if there are non-alphabet characters present in the + input. + + The alphabet uses '-' instead of '+' and '_' instead of '/'. + """ + s = _bytes_from_decode_data(s) + s = s.translate(_urlsafe_decode_translation) + return b64decode(s) + + + +# Base32 encoding/decoding must be done in Python +_b32alphabet = { + 0: b'A', 9: b'J', 18: b'S', 27: b'3', + 1: b'B', 10: b'K', 19: b'T', 28: b'4', + 2: b'C', 11: b'L', 20: b'U', 29: b'5', + 3: b'D', 12: b'M', 21: b'V', 30: b'6', + 4: b'E', 13: b'N', 22: b'W', 31: b'7', + 5: b'F', 14: b'O', 23: b'X', + 6: b'G', 15: b'P', 24: b'Y', + 7: b'H', 16: b'Q', 25: b'Z', + 8: b'I', 17: b'R', 26: b'2', + } + +_b32tab = [v[0] for k, v in sorted(_b32alphabet.items())] +_b32rev = dict([(v[0], k) for k, v in _b32alphabet.items()]) + + +def b32encode(s): + """Encode a byte string using Base32. + + s is the byte string to encode. The encoded byte string is returned. + """ + if not isinstance(s, bytes_types): + raise TypeError("expected bytes, not %s" % s.__class__.__name__) + quanta, leftover = divmod(len(s), 5) + # Pad the last quantum with zero bits if necessary + if leftover: + s = s + bytes(5 - leftover) # Don't use += ! + quanta += 1 + encoded = bytearray() + 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 + encoded += bytes([_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) + ]) + # Adjust for any leftover partial quanta + if leftover == 1: + encoded[-6:] = b'======' + elif leftover == 2: + encoded[-4:] = b'====' + elif leftover == 3: + encoded[-3:] = b'===' + elif leftover == 4: + encoded[-1:] = b'=' + return bytes(encoded) + + +def b32decode(s, casefold=False, map01=None): + """Decode a Base32 encoded byte string. + + s is the byte 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 byte string is returned. binascii.Error is raised if + the input is incorrectly padded or if there are non-alphabet + characters present in the input. + """ + s = _bytes_from_decode_data(s) + quanta, leftover = divmod(len(s), 8) + if leftover: + raise binascii.Error('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 is not None: + map01 = _bytes_from_decode_data(map01) + assert len(map01) == 1, repr(map01) + s = s.translate(bytes.maketrans(b'01', b'O' + 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(b'(?P[=]*)$', 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 binascii.Error('Non-base32 digit found') + acc += _b32rev[c] << shift + shift -= 5 + if shift < 0: + parts.append(binascii.unhexlify(bytes('%010x' % acc, "ascii"))) + acc = 0 + shift = 35 + # Process the last, partial quanta + last = binascii.unhexlify(bytes('%010x' % acc, "ascii")) + if padchars == 0: + last = b'' # 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 binascii.Error('Incorrect padding') + parts.append(last) + return b''.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 byte string using Base16. + + s is the byte string to encode. The encoded byte string is returned. + """ + if not isinstance(s, bytes_types): + raise TypeError("expected bytes, not %s" % s.__class__.__name__) + return binascii.hexlify(s).upper() + + +def b16decode(s, casefold=False): + """Decode a Base16 encoded byte string. + + s is the byte 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 byte string is returned. binascii.Error is raised if + s were incorrectly padded or if there are non-alphabet characters + present in the string. + """ + s = _bytes_from_decode_data(s) + if casefold: + s = s.upper() + if re.search(b'[^0-9A-F]', s): + raise binascii.Error('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. The files should be opened in binary mode. + +MAXLINESIZE = 76 # Excluding the CRLF +MAXBINSIZE = (MAXLINESIZE//4)*3 + +def encode(input, output): + """Encode a file; input and output are binary files.""" + 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; input and output are binary files.""" + while True: + line = input.readline() + if not line: + break + s = binascii.a2b_base64(line) + output.write(s) + + +def encodebytes(s): + """Encode a bytestring into a bytestring containing multiple lines + of base-64 data.""" + if not isinstance(s, bytes_types): + raise TypeError("expected bytes, not %s" % s.__class__.__name__) + pieces = [] + for i in range(0, len(s), MAXBINSIZE): + chunk = s[i : i + MAXBINSIZE] + pieces.append(binascii.b2a_base64(chunk)) + return b"".join(pieces) + +def encodestring(s): + """Legacy alias of encodebytes().""" + import warnings + warnings.warn("encodestring() is a deprecated alias, use encodebytes()", + DeprecationWarning, 2) + return encodebytes(s) + + +def decodebytes(s): + """Decode a bytestring of base-64 data into a bytestring.""" + if not isinstance(s, bytes_types): + raise TypeError("expected bytes, not %s" % s.__class__.__name__) + return binascii.a2b_base64(s) + +def decodestring(s): + """Legacy alias of decodebytes().""" + import warnings + warnings.warn("decodestring() is a deprecated alias, use decodebytes()", + DeprecationWarning, 2) + return decodebytes(s) + + +# Usable as a script... +def main(): + """Small main program""" + import sys, getopt + try: + opts, args = getopt.getopt(sys.argv[1:], 'deut') + except getopt.error as 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': test(); return + if args and args[0] != '-': + with open(args[0], 'rb') as f: + func(f, sys.stdout.buffer) + else: + func(sys.stdin.buffer, sys.stdout.buffer) + + +def test(): + s0 = b"Aladdin:open sesame" + print(repr(s0)) + s1 = encodebytes(s0) + print(repr(s1)) + s2 = decodebytes(s1) + print(repr(s2)) + assert s0 == s2 + + +if __name__ == '__main__': + main()