Files
PGPy-3_13_patch/pgpy/packet/subpackets/signature.py
2014-09-30 18:38:10 -07:00

854 lines
23 KiB
Python

""" signature.py
Signature SubPackets
"""
import binascii
import calendar
from datetime import datetime
from datetime import timedelta
import six
from .types import EmbeddedSignatureHeader
from .types import Signature
from ...constants import CompressionAlgorithm
from ...constants import Features as _Features
from ...constants import HashAlgorithm
from ...constants import KeyFlags as _KeyFlags
from ...constants import KeyServerPreferences as _KeyServerPreferences
from ...constants import NotationDataFlags
from ...constants import PubKeyAlgorithm
from ...constants import RevocationKeyClass
from ...constants import RevocationReason
from ...constants import SymmetricKeyAlgorithm
from ...decorators import sdproperty
from ...types import Fingerprint
class URI(Signature):
@sdproperty
def uri(self):
return self._uri
@uri.register(str)
@uri.register(six.text_type)
def uri_str(self, val):
self._uri = val
@uri.register(bytearray)
def uri_bytearray(self, val):
self.uri = val.decode('latin-1')
def __init__(self):
super(URI, self).__init__()
self.uri = ""
def __bytes__(self):
_bytes = super(URI, self).__bytes__()
_bytes += self.uri.encode()
return _bytes
def parse(self, packet):
super(URI, self).parse(packet)
self.uri = packet[:(self.header.length - 1)]
del packet[:(self.header.length - 1)]
class FlagList(Signature):
__flags__ = None
@sdproperty
def flags(self):
return self._flags
@flags.register(list)
def flags_(self, val):
self._flags = val
@flags.register(int)
@flags.register(CompressionAlgorithm)
@flags.register(HashAlgorithm)
@flags.register(PubKeyAlgorithm)
@flags.register(SymmetricKeyAlgorithm)
def flags_int(self, val):
if self.__flags__ is None: # pragma: no cover
raise AttributeError("Error: __flags__ not set!")
self._flags.append(self.__flags__(val))
@flags.register(bytearray)
def flags_bytearray(self, val):
self.flags = self.bytes_to_int(val)
def __init__(self):
super(FlagList, self).__init__()
self.flags = []
def __bytes__(self):
_bytes = super(FlagList, self).__bytes__()
_bytes += b''.join(self.int_to_bytes(b) for b in self.flags)
return _bytes
def parse(self, packet):
super(FlagList, self).parse(packet)
for i in range(0, self.header.length - 1):
self.flags = packet[:1]
del packet[:1]
class ByteFlag(Signature):
__flags__ = None
@sdproperty
def flags(self):
return self._flags
@flags.register(set)
@flags.register(list)
def flags_seq(self, val):
self._flags = val
@flags.register(int)
@flags.register(_KeyFlags)
def flags_(self, val):
if self.__flags__ is None: # pragma: no cover
raise AttributeError("Error: __flags__ not set!")
self._flags += self.__flags__ & val
@flags.register(bytearray)
def flags_bytearray(self, val):
self.flags = self.bytes_to_int(val)
def __init__(self):
super(ByteFlag, self).__init__()
self.flags = []
def __bytes__(self):
_bytes = super(ByteFlag, self).__bytes__()
_bytes += self.int_to_bytes(sum(self.flags))
return _bytes
def parse(self, packet):
super(ByteFlag, self).parse(packet)
for i in range(0, self.header.length - 1):
self.flags = packet[:1]
del packet[:1]
class Boolean(Signature):
@sdproperty
def bflag(self):
return self._bool
@bflag.register(bool)
def bflag_bool(self, val):
self._bool = val
@bflag.register(bytearray)
def bflag_bytearray(self, val):
self.bool = bool(self.bytes_to_int(val))
def __init__(self):
super(Boolean, self).__init__()
self.bflag = False
def __bytes__(self):
_bytes = super(Boolean, self).__bytes__()
_bytes += self.int_to_bytes(int(self.bflag))
return _bytes
def __bool__(self):
return self.bflag
def __nonzero__(self):
return self.__bool__()
def parse(self, packet):
super(Boolean, self).parse(packet)
self.bflag = packet[:1]
del packet[:1]
class CreationTime(Signature):
"""
5.2.3.4. Signature Creation Time
(4-octet time field)
The time the signature was made.
MUST be present in the hashed area.
"""
__typeid__ = 0x02
@sdproperty
def created(self):
return self._created
@created.register(datetime)
def created_datetime(self, val):
self._created = val
@created.register(int)
def created_int(self, val):
self.created = datetime.utcfromtimestamp(val)
@created.register(bytearray)
def created_bytearray(self, val):
self.created = self.bytes_to_int(val)
def __init__(self):
super(CreationTime, self).__init__()
self.created = datetime.utcnow()
def __bytes__(self):
_bytes = super(CreationTime, self).__bytes__()
_bytes += self.int_to_bytes(calendar.timegm(self.created.timetuple()), 4)
return _bytes
def parse(self, packet):
super(CreationTime, self).parse(packet)
self.created = packet[:4]
del packet[:4]
class SignatureExpirationTime(Signature):
"""
5.2.3.10. Signature Expiration Time
(4-octet time field)
The validity period of the signature. This is the number of seconds
after the signature creation time that the signature expires. If
this is not present or has a value of zero, it never expires.
"""
__typeid__ = 0x03
@sdproperty
def expires(self):
return self._expires
@expires.register(timedelta)
def expires_timedelta(self, val):
self._expires = val
@expires.register(int)
def expires_int(self, val):
self.expires = timedelta(seconds=val)
@expires.register(bytearray)
def expires_bytearray(self, val):
self.expires = self.bytes_to_int(val)
def __init__(self):
super(SignatureExpirationTime, self).__init__()
self.expires = 0
def __bytes__(self):
_bytes = super(SignatureExpirationTime, self).__bytes__()
_bytes += self.int_to_bytes(int(self.expires.total_seconds()), 4)
return _bytes
def parse(self, packet):
super(SignatureExpirationTime, self).parse(packet)
self.expires = packet[:4]
del packet[:4]
class ExportableCertification(Boolean):
"""
5.2.3.11. Exportable Certification
(1 octet of exportability, 0 for not, 1 for exportable)
This subpacket denotes whether a certification signature is
"exportable", to be used by other users than the signature's issuer.
The packet body contains a Boolean flag indicating whether the
signature is exportable. If this packet is not present, the
certification is exportable; it is equivalent to a flag containing a
1.
Non-exportable, or "local", certifications are signatures made by a
user to mark a key as valid within that user's implementation only.
Thus, when an implementation prepares a user's copy of a key for
transport to another user (this is the process of "exporting" the
key), any local certification signatures are deleted from the key.
The receiver of a transported key "imports" it, and likewise trims
any local certifications. In normal operation, there won't be any,
assuming the import is performed on an exported key. However, there
are instances where this can reasonably happen. For example, if an
implementation allows keys to be imported from a key database in
addition to an exported key, then this situation can arise.
Some implementations do not represent the interest of a single user
(for example, a key server). Such implementations always trim local
certifications from any key they handle.
"""
__typeid__ = 0x04
class TrustSignature(Signature):
"""
5.2.3.13. Trust Signature
(1 octet "level" (depth), 1 octet of trust amount)
Signer asserts that the key is not only valid but also trustworthy at
the specified level. Level 0 has the same meaning as an ordinary
validity signature. Level 1 means that the signed key is asserted to
be a valid trusted introducer, with the 2nd octet of the body
specifying the degree of trust. Level 2 means that the signed key is
asserted to be trusted to issue level 1 trust signatures, i.e., that
it is a "meta introducer". Generally, a level n trust signature
asserts that a key is trusted to issue level n-1 trust signatures.
The trust amount is in a range from 0-255, interpreted such that
values less than 120 indicate partial trust and values of 120 or
greater indicate complete trust. Implementations SHOULD emit values
of 60 for partial trust and 120 for complete trust.
"""
__typeid__ = 0x05
@sdproperty
def level(self):
return self._level
@level.register(int)
def level_int(self, val):
self._level = val
@level.register(bytearray)
def level_bytearray(self, val):
self.level = self.bytes_to_int(val)
@sdproperty
def amount(self):
return self._amount
@amount.register(int)
def amount_int(self, val):
# clamp 'val' to the range 0-255
self._amount = max(0, min(val, 255))
@amount.register(bytearray)
def amount_bytearray(self, val):
self.amount = self.bytes_to_int(val)
def __init__(self):
super(TrustSignature, self).__init__()
self.level = 0
self.amount = 0
def __bytes__(self):
_bytes = super(TrustSignature, self).__bytes__()
_bytes += self.int_to_bytes(self.level)
_bytes += self.int_to_bytes(self.amount)
return _bytes
def parse(self, packet):
super(TrustSignature, self).parse(packet)
self.level = packet[:1]
del packet[:1]
self.amount = packet[:1]
del packet[:1]
class RegularExpression(Signature):
"""
5.2.3.14. Regular Expression
(null-terminated regular expression)
Used in conjunction with trust Signature packets (of level > 0) to
limit the scope of trust that is extended. Only signatures by the
target key on User IDs that match the regular expression in the body
of this packet have trust extended by the trust Signature subpacket.
The regular expression uses the same syntax as the Henry Spencer's
"almost public domain" regular expression [REGEX] package. A
description of the syntax is found in Section 8 below.
"""
__typeid__ = 0x06
@sdproperty
def regex(self):
return self._regex
@regex.register(str)
@regex.register(six.text_type)
def regex_str(self, val):
self._regex = val
@regex.register(bytearray)
def regex_bytearray(self, val):
self.regex = val.decode('latin-1')
def __init__(self):
super(RegularExpression, self).__init__()
self.regex = r''
def __bytes__(self):
_bytes = super(RegularExpression, self).__bytes__()
_bytes += self.regex.encode()
return _bytes
def parse(self, packet):
super(RegularExpression, self).parse(packet)
self.regex = packet[:(self.header.length - 1)]
del packet[:(self.header.length - 1)]
class Revocable(Boolean):
"""
5.2.3.12. Revocable
(1 octet of revocability, 0 for not, 1 for revocable)
Signature's revocability status. The packet body contains a Boolean
flag indicating whether the signature is revocable. Signatures that
are not revocable have any later revocation signatures ignored. They
represent a commitment by the signer that he cannot revoke his
signature for the life of his key. If this packet is not present,
the signature is revocable.
"""
__typeid__ = 0x07
class KeyExpirationTime(SignatureExpirationTime):
"""
5.2.3.6. Key Expiration Time
(4-octet time field)
The validity period of the key. This is the number of seconds after
the key creation time that the key expires. If this is not present
or has a value of zero, the key never expires. This is found only on
a self-signature.
"""
__typeid__ = 0x09
class PreferredSymmetricAlgorithms(FlagList):
"""
5.2.3.7. Preferred Symmetric Algorithms
(array of one-octet values)
Symmetric algorithm numbers that indicate which algorithms the key
holder prefers to use. The subpacket body is an ordered list of
octets with the most preferred listed first. It is assumed that only
algorithms listed are supported by the recipient's software.
Algorithm numbers are in Section 9. This is only found on a self-
signature.
"""
__typeid__ = 0x0B
__flags__ = SymmetricKeyAlgorithm
class RevocationKey(Signature):
"""
5.2.3.15. Revocation Key
(1 octet of class, 1 octet of public-key algorithm ID, 20 octets of
fingerprint)
Authorizes the specified key to issue revocation signatures for this
key. Class octet must have bit 0x80 set. If the bit 0x40 is set,
then this means that the revocation information is sensitive. Other
bits are for future expansion to other kinds of authorizations. This
is found on a self-signature.
If the "sensitive" flag is set, the keyholder feels this subpacket
contains private trust information that describes a real-world
sensitive relationship. If this flag is set, implementations SHOULD
NOT export this signature to other users except in cases where the
data needs to be available: when the signature is being sent to the
designated revoker, or when it is accompanied by a revocation
signature from that revoker. Note that it may be appropriate to
isolate this subpacket within a separate signature so that it is not
combined with other subpackets that need to be exported.
"""
__typeid__ = 0x0C
@sdproperty
def keyclass(self):
return self._keyclass
@keyclass.register(list)
def keyclass_list(self, val):
self._keyclass = val
@keyclass.register(int)
@keyclass.register(RevocationKeyClass)
def keyclass_int(self, val):
self._keyclass += RevocationKeyClass & val
@keyclass.register(bytearray)
def keyclass_bytearray(self, val):
self.keyclass = self.bytes_to_int(val)
@sdproperty
def algorithm(self):
return self._algorithm
@algorithm.register(int)
@algorithm.register(PubKeyAlgorithm)
def algorithm_int(self, val):
self._algorithm = PubKeyAlgorithm(val)
@algorithm.register(bytearray)
def algorithm_bytearray(self, val):
self.algorithm = self.bytes_to_int(val)
@sdproperty
def fingerprint(self):
return self._fingerprint
@fingerprint.register(str)
@fingerprint.register(six.text_type)
@fingerprint.register(Fingerprint)
def fingerprint_str(self, val):
self._fingerprint = Fingerprint(val)
@fingerprint.register(bytearray)
def fingerprint_bytearray(self, val):
self.fingerprint = ''.join('{:02x}'.format(c) for c in val).upper()
def __init__(self):
super(RevocationKey, self).__init__()
self.keyclass = []
self.algorithm = PubKeyAlgorithm.Invalid
self._fingerprint = ""
def __bytes__(self):
_bytes = super(RevocationKey, self).__bytes__()
_bytes += self.int_to_bytes(sum(self.keyclass))
_bytes += self.int_to_bytes(self.algorithm.value)
# _bytes += self.int_to_bytes(int(self.fingerprint), 20)
_bytes += self.fingerprint.__bytes__()
return _bytes
def parse(self, packet):
super(RevocationKey, self).parse(packet)
self.keyclass = packet[:1]
del packet[:1]
self.algorithm = packet[:1]
del packet[:1]
self.fingerprint = packet[:20]
del packet[:20]
class Issuer(Signature):
__typeid__ = 0x10
@sdproperty
def issuer(self):
return self._issuer
@issuer.register(bytearray)
def issuer_bytearray(self, val):
self._issuer = binascii.hexlify(val).upper().decode('latin-1')
def __init__(self):
super(Issuer, self).__init__()
self.issuer = bytearray()
def __bytes__(self):
_bytes = super(Issuer, self).__bytes__()
_bytes += binascii.unhexlify(self._issuer.encode())
return _bytes
def parse(self, packet):
super(Issuer, self).parse(packet)
self.issuer = packet[:8]
del packet[:8]
class NotationData(Signature):
__typeid__ = 0x14
@sdproperty
def flags(self):
return self._flags
@flags.register(list)
def flags_list(self, val):
self._flags = val
@flags.register(int)
@flags.register(NotationDataFlags)
def flags_int(self, val):
self.flags += NotationDataFlags & val
@flags.register(bytearray)
def flags_bytearray(self, val):
self.flags = self.bytes_to_int(val)
@sdproperty
def name(self):
return self._name
@name.register(str)
@name.register(six.text_type)
def name_str(self, val):
self._name = val
@name.register(bytearray)
def name_bytearray(self, val):
self.name = val.decode('latin-1')
@sdproperty
def value(self):
return self._value
@value.register(str)
@value.register(six.text_type)
def value_str(self, val):
self._value = val
@value.register(bytearray)
def value_bytearray(self, val):
if NotationDataFlags.HumanReadable in self.flags:
self.value = val.decode('latin-1')
else: # pragma: no cover
self._value = val
def __init__(self):
super(NotationData, self).__init__()
self.flags = [0, 0, 0, 0]
self.name = ""
self.value = ""
def __bytes__(self):
_bytes = super(NotationData, self).__bytes__()
_bytes += self.int_to_bytes(sum(self.flags)) + b'\x00\x00\x00'
_bytes += self.int_to_bytes(len(self.name), 2)
_bytes += self.int_to_bytes(len(self.value), 2)
_bytes += self.name.encode()
_bytes += self.value if isinstance(self.value, (bytearray, bytes)) else self.value.encode()
return _bytes
def parse(self, packet):
super(NotationData, self).parse(packet)
self.flags = packet[:1]
del packet[:4]
nlen = self.bytes_to_int(packet[:2])
del packet[:2]
vlen = self.bytes_to_int(packet[:2])
del packet[:2]
self.name = packet[:nlen]
del packet[:nlen]
self.value = packet[:vlen]
del packet[:vlen]
class PreferredHashAlgorithms(FlagList):
__typeid__ = 0x15
__flags__ = HashAlgorithm
class PreferredCompressionAlgorithms(FlagList):
__typeid__ = 0x16
__flags__ = CompressionAlgorithm
class KeyServerPreferences(FlagList):
__typeid__ = 0x17
__flags__ = _KeyServerPreferences
class PreferredKeyServer(URI):
__typeid__ = 0x18
class PrimaryUserID(Signature):
__typeid__ = 0x19
@sdproperty
def primary(self):
return self._primary
@primary.register(bool)
def primary_bool(self, val):
self._primary = val
@primary.register(bytearray)
def primary_byrearray(self, val):
self.primary = bool(self.bytes_to_int(val))
def __init__(self):
super(PrimaryUserID, self).__init__()
self.primary = True
def __bytes__(self):
_bytes = super(PrimaryUserID, self).__bytes__()
_bytes += self.int_to_bytes(int(self.primary))
return _bytes
def __bool__(self):
return self.primary
def __nonzero__(self):
return self.__bool__()
def parse(self, packet):
super(PrimaryUserID, self).parse(packet)
self.primary = packet[:1]
del packet[:1]
class Policy(URI):
__typeid__ = 0x1a
class KeyFlags(ByteFlag):
__typeid__ = 0x1B
__flags__ = _KeyFlags
class SignersUserID(Signature):
__typeid__ = 0x1C
@sdproperty
def userid(self):
return self._userid
@userid.register(str)
@userid.register(six.text_type)
def userid_str(self, val):
self._userid = val
@userid.register(bytearray)
def userid_bytearray(self, val):
self.userid = val.decode('latin-1')
def __init__(self):
super(SignersUserID, self).__init__()
self.userid = ""
def __bytes__(self):
_bytes = super(SignersUserID, self).__bytes__()
_bytes += self.userid.encode()
return _bytes
def parse(self, packet):
super(SignersUserID, self).parse(packet)
self.userid = packet[:(self.header.length - 1)]
del packet[:(self.header.length - 1)]
class ReasonForRevocation(Signature):
__typeid__ = 0x1D
@sdproperty
def code(self):
return self._code
@code.register(int)
@code.register(RevocationReason)
def code_int(self, val):
self._code = RevocationReason(val)
@code.register(bytearray)
def code_bytearray(self, val):
self.code = self.bytes_to_int(val)
@sdproperty
def string(self):
return self._string
@string.register(str)
@string.register(six.text_type)
def string_str(self, val):
self._string = val
@string.register(bytearray)
def string_bytearray(self, val):
self.string = val.decode('latin-1')
def __init__(self):
super(ReasonForRevocation, self).__init__()
self.code = 0x00
self.string = ""
def __bytes__(self):
_bytes = super(ReasonForRevocation, self).__bytes__()
_bytes += self.int_to_bytes(self.code)
_bytes += self.string.encode()
return _bytes
def parse(self, packet):
super(ReasonForRevocation, self).parse(packet)
self.code = packet[:1]
del packet[:1]
self.string = packet[:(self.header.length - 2)]
del packet[:(self.header.length - 2)]
class Features(ByteFlag):
__typeid__ = 0x1E
__flags__ = _Features
##TODO: obtain subpacket type 0x1F - Signature Target
class EmbeddedSignature(Signature):
__typeid__ = 0x20
@sdproperty
def _sig(self):
return self._sigpkt
@_sig.setter
def _sig(self, val):
val.header = EmbeddedSignatureHeader()
val.update_hlen()
self._sigpkt = val
@property
def sigtype(self):
return self._sig.sigtype
@property
def pubalg(self):
return self._sig.pubalg
@property
def halg(self):
return self._sig.halg
@property
def subpackets(self):
return self._sig.subpackets
@property
def hash2(self): # pragma: no cover
return self._sig.hash2
@property
def signature(self):
return self._sig.signature
@property
def signer(self):
return self._sig.signer
def __init__(self):
super(EmbeddedSignature, self).__init__()
from ..packets import SignatureV4
self._sigpkt = SignatureV4()
self._sigpkt.header = EmbeddedSignatureHeader()
def __bytes__(self):
return super(EmbeddedSignature, self).__bytes__() + self._sigpkt.__bytes__()
def parse(self, packet):
super(EmbeddedSignature, self).parse(packet)
self._sig.parse(packet)