diff options
Diffstat (limited to 'third_party/python/idna/idna/core.py')
-rw-r--r-- | third_party/python/idna/idna/core.py | 400 |
1 files changed, 400 insertions, 0 deletions
diff --git a/third_party/python/idna/idna/core.py b/third_party/python/idna/idna/core.py new file mode 100644 index 0000000000..41ec5c711d --- /dev/null +++ b/third_party/python/idna/idna/core.py @@ -0,0 +1,400 @@ +from . import idnadata +import bisect +import unicodedata +import re +import sys +from .intranges import intranges_contain + +_virama_combining_class = 9 +_alabel_prefix = b'xn--' +_unicode_dots_re = re.compile(u'[\u002e\u3002\uff0e\uff61]') + +if sys.version_info[0] >= 3: + unicode = str + unichr = chr + +class IDNAError(UnicodeError): + """ Base exception for all IDNA-encoding related problems """ + pass + + +class IDNABidiError(IDNAError): + """ Exception when bidirectional requirements are not satisfied """ + pass + + +class InvalidCodepoint(IDNAError): + """ Exception when a disallowed or unallocated codepoint is used """ + pass + + +class InvalidCodepointContext(IDNAError): + """ Exception when the codepoint is not valid in the context it is used """ + pass + + +def _combining_class(cp): + v = unicodedata.combining(unichr(cp)) + if v == 0: + if not unicodedata.name(unichr(cp)): + raise ValueError("Unknown character in unicodedata") + return v + +def _is_script(cp, script): + return intranges_contain(ord(cp), idnadata.scripts[script]) + +def _punycode(s): + return s.encode('punycode') + +def _unot(s): + return 'U+{0:04X}'.format(s) + + +def valid_label_length(label): + + if len(label) > 63: + return False + return True + + +def valid_string_length(label, trailing_dot): + + if len(label) > (254 if trailing_dot else 253): + return False + return True + + +def check_bidi(label, check_ltr=False): + + # Bidi rules should only be applied if string contains RTL characters + bidi_label = False + for (idx, cp) in enumerate(label, 1): + direction = unicodedata.bidirectional(cp) + if direction == '': + # String likely comes from a newer version of Unicode + raise IDNABidiError('Unknown directionality in label {0} at position {1}'.format(repr(label), idx)) + if direction in ['R', 'AL', 'AN']: + bidi_label = True + if not bidi_label and not check_ltr: + return True + + # Bidi rule 1 + direction = unicodedata.bidirectional(label[0]) + if direction in ['R', 'AL']: + rtl = True + elif direction == 'L': + rtl = False + else: + raise IDNABidiError('First codepoint in label {0} must be directionality L, R or AL'.format(repr(label))) + + valid_ending = False + number_type = False + for (idx, cp) in enumerate(label, 1): + direction = unicodedata.bidirectional(cp) + + if rtl: + # Bidi rule 2 + if not direction in ['R', 'AL', 'AN', 'EN', 'ES', 'CS', 'ET', 'ON', 'BN', 'NSM']: + raise IDNABidiError('Invalid direction for codepoint at position {0} in a right-to-left label'.format(idx)) + # Bidi rule 3 + if direction in ['R', 'AL', 'EN', 'AN']: + valid_ending = True + elif direction != 'NSM': + valid_ending = False + # Bidi rule 4 + if direction in ['AN', 'EN']: + if not number_type: + number_type = direction + else: + if number_type != direction: + raise IDNABidiError('Can not mix numeral types in a right-to-left label') + else: + # Bidi rule 5 + if not direction in ['L', 'EN', 'ES', 'CS', 'ET', 'ON', 'BN', 'NSM']: + raise IDNABidiError('Invalid direction for codepoint at position {0} in a left-to-right label'.format(idx)) + # Bidi rule 6 + if direction in ['L', 'EN']: + valid_ending = True + elif direction != 'NSM': + valid_ending = False + + if not valid_ending: + raise IDNABidiError('Label ends with illegal codepoint directionality') + + return True + + +def check_initial_combiner(label): + + if unicodedata.category(label[0])[0] == 'M': + raise IDNAError('Label begins with an illegal combining character') + return True + + +def check_hyphen_ok(label): + + if label[2:4] == '--': + raise IDNAError('Label has disallowed hyphens in 3rd and 4th position') + if label[0] == '-' or label[-1] == '-': + raise IDNAError('Label must not start or end with a hyphen') + return True + + +def check_nfc(label): + + if unicodedata.normalize('NFC', label) != label: + raise IDNAError('Label must be in Normalization Form C') + + +def valid_contextj(label, pos): + + cp_value = ord(label[pos]) + + if cp_value == 0x200c: + + if pos > 0: + if _combining_class(ord(label[pos - 1])) == _virama_combining_class: + return True + + ok = False + for i in range(pos-1, -1, -1): + joining_type = idnadata.joining_types.get(ord(label[i])) + if joining_type == ord('T'): + continue + if joining_type in [ord('L'), ord('D')]: + ok = True + break + + if not ok: + return False + + ok = False + for i in range(pos+1, len(label)): + joining_type = idnadata.joining_types.get(ord(label[i])) + if joining_type == ord('T'): + continue + if joining_type in [ord('R'), ord('D')]: + ok = True + break + return ok + + if cp_value == 0x200d: + + if pos > 0: + if _combining_class(ord(label[pos - 1])) == _virama_combining_class: + return True + return False + + else: + + return False + + +def valid_contexto(label, pos, exception=False): + + cp_value = ord(label[pos]) + + if cp_value == 0x00b7: + if 0 < pos < len(label)-1: + if ord(label[pos - 1]) == 0x006c and ord(label[pos + 1]) == 0x006c: + return True + return False + + elif cp_value == 0x0375: + if pos < len(label)-1 and len(label) > 1: + return _is_script(label[pos + 1], 'Greek') + return False + + elif cp_value == 0x05f3 or cp_value == 0x05f4: + if pos > 0: + return _is_script(label[pos - 1], 'Hebrew') + return False + + elif cp_value == 0x30fb: + for cp in label: + if cp == u'\u30fb': + continue + if _is_script(cp, 'Hiragana') or _is_script(cp, 'Katakana') or _is_script(cp, 'Han'): + return True + return False + + elif 0x660 <= cp_value <= 0x669: + for cp in label: + if 0x6f0 <= ord(cp) <= 0x06f9: + return False + return True + + elif 0x6f0 <= cp_value <= 0x6f9: + for cp in label: + if 0x660 <= ord(cp) <= 0x0669: + return False + return True + + +def check_label(label): + + if isinstance(label, (bytes, bytearray)): + label = label.decode('utf-8') + if len(label) == 0: + raise IDNAError('Empty Label') + + check_nfc(label) + check_hyphen_ok(label) + check_initial_combiner(label) + + for (pos, cp) in enumerate(label): + cp_value = ord(cp) + if intranges_contain(cp_value, idnadata.codepoint_classes['PVALID']): + continue + elif intranges_contain(cp_value, idnadata.codepoint_classes['CONTEXTJ']): + try: + if not valid_contextj(label, pos): + raise InvalidCodepointContext('Joiner {0} not allowed at position {1} in {2}'.format( + _unot(cp_value), pos+1, repr(label))) + except ValueError: + raise IDNAError('Unknown codepoint adjacent to joiner {0} at position {1} in {2}'.format( + _unot(cp_value), pos+1, repr(label))) + elif intranges_contain(cp_value, idnadata.codepoint_classes['CONTEXTO']): + if not valid_contexto(label, pos): + raise InvalidCodepointContext('Codepoint {0} not allowed at position {1} in {2}'.format(_unot(cp_value), pos+1, repr(label))) + else: + raise InvalidCodepoint('Codepoint {0} at position {1} of {2} not allowed'.format(_unot(cp_value), pos+1, repr(label))) + + check_bidi(label) + + +def alabel(label): + + try: + label = label.encode('ascii') + ulabel(label) + if not valid_label_length(label): + raise IDNAError('Label too long') + return label + except UnicodeEncodeError: + pass + + if not label: + raise IDNAError('No Input') + + label = unicode(label) + check_label(label) + label = _punycode(label) + label = _alabel_prefix + label + + if not valid_label_length(label): + raise IDNAError('Label too long') + + return label + + +def ulabel(label): + + if not isinstance(label, (bytes, bytearray)): + try: + label = label.encode('ascii') + except UnicodeEncodeError: + check_label(label) + return label + + label = label.lower() + if label.startswith(_alabel_prefix): + label = label[len(_alabel_prefix):] + if not label: + raise IDNAError('Malformed A-label, no Punycode eligible content found') + if label.decode('ascii')[-1] == '-': + raise IDNAError('A-label must not end with a hyphen') + else: + check_label(label) + return label.decode('ascii') + + label = label.decode('punycode') + check_label(label) + return label + + +def uts46_remap(domain, std3_rules=True, transitional=False): + """Re-map the characters in the string according to UTS46 processing.""" + from .uts46data import uts46data + output = u"" + try: + for pos, char in enumerate(domain): + code_point = ord(char) + uts46row = uts46data[code_point if code_point < 256 else + bisect.bisect_left(uts46data, (code_point, "Z")) - 1] + status = uts46row[1] + replacement = uts46row[2] if len(uts46row) == 3 else None + if (status == "V" or + (status == "D" and not transitional) or + (status == "3" and not std3_rules and replacement is None)): + output += char + elif replacement is not None and (status == "M" or + (status == "3" and not std3_rules) or + (status == "D" and transitional)): + output += replacement + elif status != "I": + raise IndexError() + return unicodedata.normalize("NFC", output) + except IndexError: + raise InvalidCodepoint( + "Codepoint {0} not allowed at position {1} in {2}".format( + _unot(code_point), pos + 1, repr(domain))) + + +def encode(s, strict=False, uts46=False, std3_rules=False, transitional=False): + + if isinstance(s, (bytes, bytearray)): + s = s.decode("ascii") + if uts46: + s = uts46_remap(s, std3_rules, transitional) + trailing_dot = False + result = [] + if strict: + labels = s.split('.') + else: + labels = _unicode_dots_re.split(s) + if not labels or labels == ['']: + raise IDNAError('Empty domain') + if labels[-1] == '': + del labels[-1] + trailing_dot = True + for label in labels: + s = alabel(label) + if s: + result.append(s) + else: + raise IDNAError('Empty label') + if trailing_dot: + result.append(b'') + s = b'.'.join(result) + if not valid_string_length(s, trailing_dot): + raise IDNAError('Domain too long') + return s + + +def decode(s, strict=False, uts46=False, std3_rules=False): + + if isinstance(s, (bytes, bytearray)): + s = s.decode("ascii") + if uts46: + s = uts46_remap(s, std3_rules, False) + trailing_dot = False + result = [] + if not strict: + labels = _unicode_dots_re.split(s) + else: + labels = s.split(u'.') + if not labels or labels == ['']: + raise IDNAError('Empty domain') + if not labels[-1]: + del labels[-1] + trailing_dot = True + for label in labels: + s = ulabel(label) + if s: + result.append(s) + else: + raise IDNAError('Empty label') + if trailing_dot: + result.append(u'') + return u'.'.join(result) |