1 files changed, 384 insertions, 0 deletions
diff --git a/freezed_deps/ecdsa/der.py b/freezed_deps/ecdsa/der.py
new file mode 100644
index 0000000..ad75b37
--- /dev/null
+++ b/freezed_deps/ecdsa/der.py
@@ -0,0 +1,384 @@
+from __future__ import division
+
+import binascii
+import base64
+import warnings
+from itertools import chain
+from six import int2byte, b, text_type
+from ._compat import str_idx_as_int
+
+
+class UnexpectedDER(Exception):
+    pass
+
+
+def encode_constructed(tag, value):
+    return int2byte(0xa0+tag) + encode_length(len(value)) + value
+
+
+def encode_integer(r):
+    assert r >= 0  # can't support negative numbers yet
+    h = ("%x" % r).encode()
+    if len(h) % 2:
+        h = b("0") + h
+    s = binascii.unhexlify(h)
+    num = str_idx_as_int(s, 0)
+    if num <= 0x7f:
+        return b("\x02") + encode_length(len(s)) + s
+    else:
+        # DER integers are two's complement, so if the first byte is
+        # 0x80-0xff then we need an extra 0x00 byte to prevent it from
+        # looking negative.
+        return b("\x02") + encode_length(len(s)+1) + b("\x00") + s
+
+
+# sentry object to check if an argument was specified (used to detect
+# deprecated calling convention)
+_sentry = object()
+
+
+def encode_bitstring(s, unused=_sentry):
+    """
+    Encode a binary string as a BIT STRING using :term:`DER` encoding.
+
+    Note, because there is no native Python object that can encode an actual
+    bit string, this function only accepts byte strings as the `s` argument.
+    The byte string is the actual bit string that will be encoded, padded
+    on the right (least significant bits, looking from big endian perspective)
+    to the first full byte. If the bit string has a bit length that is multiple
+    of 8, then the padding should not be included. For correct DER encoding
+    the padding bits MUST be set to 0.
+
+    Number of bits of padding need to be provided as the `unused` parameter.
+    In case they are specified as None, it means the number of unused bits
+    is already encoded in the string as the first byte.
+
+    The deprecated call convention specifies just the `s` parameters and
+    encodes the number of unused bits as first parameter (same convention
+    as with None).
+
+    Empty string must be encoded with `unused` specified as 0.
+
+    Future version of python-ecdsa will make specifying the `unused` argument
+    mandatory.
+
+    :param s: bytes to encode
+    :type s: bytes like object
+    :param unused: number of bits at the end of `s` that are unused, must be
+        between 0 and 7 (inclusive)
+    :type unused: int or None
+
+    :raises ValueError: when `unused` is too large or too small
+
+    :return: `s` encoded using DER
+    :rtype: bytes
+    """
+    encoded_unused = b''
+    len_extra = 0
+    if unused is _sentry:
+        warnings.warn("Legacy call convention used, unused= needs to be "
+                      "specified",
+                      DeprecationWarning)
+    elif unused is not None:
+        if not 0 <= unused <= 7:
+            raise ValueError("unused must be integer between 0 and 7")
+        if unused:
+            if not s:
+                raise ValueError("unused is non-zero but s is empty")
+            last = str_idx_as_int(s, -1)
+            if last & (2 ** unused - 1):
+                raise ValueError("unused bits must be zeros in DER")
+        encoded_unused = int2byte(unused)
+        len_extra = 1
+    return b("\x03") + encode_length(len(s) + len_extra) + encoded_unused + s
+
+
+def encode_octet_string(s):
+    return b("\x04") + encode_length(len(s)) + s
+
+
+def encode_oid(first, second, *pieces):
+    assert 0 <= first < 2 and 0 <= second <= 39 or first == 2 and 0 <= second
+    body = b''.join(chain([encode_number(40*first+second)],
+                          (encode_number(p) for p in pieces)))
+    return b'\x06' + encode_length(len(body)) + body
+
+
+def encode_sequence(*encoded_pieces):
+    total_len = sum([len(p) for p in encoded_pieces])
+    return b('\x30') + encode_length(total_len) + b('').join(encoded_pieces)
+
+
+def encode_number(n):
+    b128_digits = []
+    while n:
+        b128_digits.insert(0, (n & 0x7f) | 0x80)
+        n = n >> 7
+    if not b128_digits:
+        b128_digits.append(0)
+    b128_digits[-1] &= 0x7f
+    return b('').join([int2byte(d) for d in b128_digits])
+
+
+def remove_constructed(string):
+    s0 = str_idx_as_int(string, 0)
+    if (s0 & 0xe0) != 0xa0:
+        raise UnexpectedDER("wanted type 'constructed tag' (0xa0-0xbf), "
+                            "got 0x%02x" % s0)
+    tag = s0 & 0x1f
+    length, llen = read_length(string[1:])
+    body = string[1+llen:1+llen+length]
+    rest = string[1+llen+length:]
+    return tag, body, rest
+
+
+def remove_sequence(string):
+    if not string:
+        raise UnexpectedDER("Empty string does not encode a sequence")
+    if string[:1] != b"\x30":
+        n = str_idx_as_int(string, 0)
+        raise UnexpectedDER("wanted type 'sequence' (0x30), got 0x%02x" % n)
+    length, lengthlength = read_length(string[1:])
+    if length > len(string) - 1 - lengthlength:
+        raise UnexpectedDER("Length longer than the provided buffer")
+    endseq = 1+lengthlength+length
+    return string[1+lengthlength:endseq], string[endseq:]
+
+
+def remove_octet_string(string):
+    if string[:1] != b"\x04":
+        n = str_idx_as_int(string, 0)
+        raise UnexpectedDER("wanted type 'octetstring' (0x04), got 0x%02x" % n)
+    length, llen = read_length(string[1:])
+    body = string[1+llen:1+llen+length]
+    rest = string[1+llen+length:]
+    return body, rest
+
+
+def remove_object(string):
+    if not string:
+        raise UnexpectedDER(
+            "Empty string does not encode an object identifier")
+    if string[:1] != b"\x06":
+        n = str_idx_as_int(string, 0)
+        raise UnexpectedDER("wanted type 'object' (0x06), got 0x%02x" % n)
+    length, lengthlength = read_length(string[1:])
+    body = string[1+lengthlength:1+lengthlength+length]
+    rest = string[1+lengthlength+length:]
+    if not body:
+        raise UnexpectedDER("Empty object identifier")
+    if len(body) != length:
+        raise UnexpectedDER(
+            "Length of object identifier longer than the provided buffer")
+    numbers = []
+    while body:
+        n, ll = read_number(body)
+        numbers.append(n)
+        body = body[ll:]
+    n0 = numbers.pop(0)
+    if n0 < 80:
+        first = n0 // 40
+    else:
+        first = 2
+    second = n0 - (40 * first)
+    numbers.insert(0, first)
+    numbers.insert(1, second)
+    return tuple(numbers), rest
+
+
+def remove_integer(string):
+    if not string:
+        raise UnexpectedDER("Empty string is an invalid encoding of an "
+                            "integer")
+    if string[:1] != b"\x02":
+        n = str_idx_as_int(string, 0)
+        raise UnexpectedDER("wanted type 'integer' (0x02), got 0x%02x" % n)
+    length, llen = read_length(string[1:])
+    if length > len(string) - 1 - llen:
+        raise UnexpectedDER("Length longer than provided buffer")
+    if length == 0:
+        raise UnexpectedDER("0-byte long encoding of integer")
+    numberbytes = string[1+llen:1+llen+length]
+    rest = string[1+llen+length:]
+    msb = str_idx_as_int(numberbytes, 0)
+    if not msb < 0x80:
+        raise UnexpectedDER("Negative integers are not supported")
+    # check if the encoding is the minimal one (DER requirement)
+    if length > 1 and not msb:
+        # leading zero byte is allowed if the integer would have been
+        # considered a negative number otherwise
+        smsb = str_idx_as_int(numberbytes, 1)
+        if smsb < 0x80:
+            raise UnexpectedDER("Invalid encoding of integer, unnecessary "
+                                "zero padding bytes")
+    return int(binascii.hexlify(numberbytes), 16), rest
+
+
+def read_number(string):
+    number = 0
+    llen = 0
+    if str_idx_as_int(string, 0) == 0x80:
+        raise UnexpectedDER("Non minimal encoding of OID subidentifier")
+    # base-128 big endian, with most significant bit set in all but the last
+    # byte
+    while True:
+        if llen >= len(string):
+            raise UnexpectedDER("ran out of length bytes")
+        number = number << 7
+        d = str_idx_as_int(string, llen)
+        number += (d & 0x7f)
+        llen += 1
+        if not d & 0x80:
+            break
+    return number, llen
+
+
+def encode_length(l):
+    assert l >= 0
+    if l < 0x80:
+        return int2byte(l)
+    s = ("%x" % l).encode()
+    if len(s) % 2:
+        s = b("0") + s
+    s = binascii.unhexlify(s)
+    llen = len(s)
+    return int2byte(0x80 | llen) + s
+
+
+def read_length(string):
+    if not string:
+        raise UnexpectedDER("Empty string can't encode valid length value")
+    num = str_idx_as_int(string, 0)
+    if not (num & 0x80):
+        # short form
+        return (num & 0x7f), 1
+    # else long-form: b0&0x7f is number of additional base256 length bytes,
+    # big-endian
+    llen = num & 0x7f
+    if not llen:
+        raise UnexpectedDER("Invalid length encoding, length of length is 0")
+    if llen > len(string)-1:
+        raise UnexpectedDER("Length of length longer than provided buffer")
+    # verify that the encoding is minimal possible (DER requirement)
+    msb = str_idx_as_int(string, 1)
+    if not msb or llen == 1 and msb < 0x80:
+        raise UnexpectedDER("Not minimal encoding of length")
+    return int(binascii.hexlify(string[1:1+llen]), 16), 1+llen
+
+
+def remove_bitstring(string, expect_unused=_sentry):
+    """
+    Remove a BIT STRING object from `string` following :term:`DER`.
+
+    The `expect_unused` can be used to specify if the bit string should
+    have the amount of unused bits decoded or not. If it's an integer, any
+    read BIT STRING that has number of unused bits different from specified
+    value will cause UnexpectedDER exception to be raised (this is especially
+    useful when decoding BIT STRINGS that have DER encoded object in them;
+    DER encoding is byte oriented, so the unused bits will always equal 0).
+
+    If the `expect_unused` is specified as None, the first element returned
+    will be a tuple, with the first value being the extracted bit string
+    while the second value will be the decoded number of unused bits.
+
+    If the `expect_unused` is unspecified, the decoding of byte with
+    number of unused bits will not be attempted and the bit string will be
+    returned as-is, the callee will be required to decode it and verify its
+    correctness.
+
+    Future version of python will require the `expected_unused` parameter
+    to be specified.
+
+    :param string: string of bytes to extract the BIT STRING from
+    :type string: bytes like object
+    :param expect_unused: number of bits that should be unused in the BIT
+        STRING, or None, to return it to caller
+    :type expect_unused: int or None
+
+    :raises UnexpectedDER: when the encoding does not follow DER.
+
+    :return: a tuple with first element being the extracted bit string and
+        the second being the remaining bytes in the string (if any); if the
+        `expect_unused` is specified as None, the first element of the returned
+        tuple will be a tuple itself, with first element being the bit string
+        as bytes and the second element being the number of unused bits at the
+        end of the byte array as an integer
+    :rtype: tuple
+    """
+    if not string:
+        raise UnexpectedDER("Empty string does not encode a bitstring")
+    if expect_unused is _sentry:
+        warnings.warn("Legacy call convention used, expect_unused= needs to be"
+                      " specified",
+                      DeprecationWarning)
+    num = str_idx_as_int(string, 0)
+    if string[:1] != b"\x03":
+        raise UnexpectedDER("wanted bitstring (0x03), got 0x%02x" % num)
+    length, llen = read_length(string[1:])
+    if not length:
+        raise UnexpectedDER("Invalid length of bit string, can't be 0")
+    body = string[1+llen:1+llen+length]
+    rest = string[1+llen+length:]
+    if expect_unused is not _sentry:
+        unused = str_idx_as_int(body, 0)
+        if not 0 <= unused <= 7:
+            raise UnexpectedDER("Invalid encoding of unused bits")
+        if expect_unused is not None and expect_unused != unused:
+            raise UnexpectedDER("Unexpected number of unused bits")
+        body = body[1:]
+        if unused:
+            if not body:
+                raise UnexpectedDER("Invalid encoding of empty bit string")
+            last = str_idx_as_int(body, -1)
+            # verify that all the unused bits are set to zero (DER requirement)
+            if last & (2 ** unused - 1):
+                raise UnexpectedDER("Non zero padding bits in bit string")
+        if expect_unused is None:
+            body = (body, unused)
+    return body, rest
+
+# SEQUENCE([1, STRING(secexp), cont[0], OBJECT(curvename), cont[1], BINTSTRING)
+
+
+# signatures: (from RFC3279)
+#  ansi-X9-62  OBJECT IDENTIFIER ::= {
+#       iso(1) member-body(2) us(840) 10045 }
+#
+#  id-ecSigType OBJECT IDENTIFIER  ::=  {
+#       ansi-X9-62 signatures(4) }
+#  ecdsa-with-SHA1  OBJECT IDENTIFIER ::= {
+#       id-ecSigType 1 }
+## so 1,2,840,10045,4,1
+## so 0x42, .. ..
+
+#  Ecdsa-Sig-Value  ::=  SEQUENCE  {
+#       r     INTEGER,
+#       s     INTEGER  }
+
+# id-public-key-type OBJECT IDENTIFIER  ::= { ansi-X9.62 2 }
+#
+# id-ecPublicKey OBJECT IDENTIFIER ::= { id-publicKeyType 1 }
+
+# I think the secp224r1 identifier is (t=06,l=05,v=2b81040021)
+#  secp224r1 OBJECT IDENTIFIER ::= {
+#  iso(1) identified-organization(3) certicom(132) curve(0) 33 }
+# and the secp384r1 is (t=06,l=05,v=2b81040022)
+#  secp384r1 OBJECT IDENTIFIER ::= {
+#  iso(1) identified-organization(3) certicom(132) curve(0) 34 }
+
+def unpem(pem):
+    if isinstance(pem, text_type):
+        pem = pem.encode()
+
+    d = b("").join([l.strip() for l in pem.split(b("\n"))
+                    if l and not l.startswith(b("-----"))])
+    return base64.b64decode(d)
+
+
+def topem(der, name):
+    b64 = base64.b64encode(der)
+    lines = [("-----BEGIN %s-----\n" % name).encode()]
+    lines.extend([b64[start:start+64]+b("\n")
+                  for start in range(0, len(b64), 64)])
+    lines.append(("-----END %s-----\n" % name).encode())
+    return b("").join(lines)