def _lengthOctets(self, payloadLen):
"""Return a byte string that encodes the given payload length (in
bytes) in a format suitable for a DER length tag (L).
"""
if payloadLen>127:
encoding = long_to_bytes(payloadLen)
return bchr(len(encoding)+128) + encoding
return bchr(payloadLen)
python类long_to_bytes()的实例源码
def encode(self):
"""Return a complete INTEGER DER element, fully encoded as a TLV."""
self.payload = long_to_bytes(self.value)
if bord(self.payload[0])>127:
self.payload = bchr(0x00) + self.payload
return DerObject.encode(self)
def MGF1(mgfSeed, maskLen, hash):
"""Mask Generation Function, described in B.2.1"""
T = b("")
for counter in xrange(ceil_div(maskLen, hash.digest_size)):
c = long_to_bytes(counter, 4)
T = T + hash.new(mgfSeed + c).digest()
assert(len(T)>=maskLen)
return T[:maskLen]
def _lengthOctets(self, payloadLen):
"""Return a byte string that encodes the given payload length (in
bytes) in a format suitable for a DER length tag (L).
"""
if payloadLen>127:
encoding = long_to_bytes(payloadLen)
return bchr(len(encoding)+128) + encoding
return bchr(payloadLen)
def encode(self):
"""Return a complete INTEGER DER element, fully encoded as a TLV."""
self.payload = long_to_bytes(self.value)
if bord(self.payload[0])>127:
self.payload = bchr(0x00) + self.payload
return DerObject.encode(self)
def MGF1(mgfSeed, maskLen, hash):
"""Mask Generation Function, described in B.2.1"""
T = b("")
for counter in xrange(ceil_div(maskLen, hash.digest_size)):
c = long_to_bytes(counter, 4)
T = T + hash.new(mgfSeed + c).digest()
assert(len(T)>=maskLen)
return T[:maskLen]
def _lengthOctets(self, payloadLen):
"""Return a byte string that encodes the given payload length (in
bytes) in a format suitable for a DER length tag (L).
"""
if payloadLen>127:
encoding = long_to_bytes(payloadLen)
return bchr(len(encoding)+128) + encoding
return bchr(payloadLen)
def encode(self):
"""Return a complete INTEGER DER element, fully encoded as a TLV."""
self.payload = long_to_bytes(self.value)
if bord(self.payload[0])>127:
self.payload = bchr(0x00) + self.payload
return DerObject.encode(self)
def longToBinary(l):
if l < 0:
raise ValueError('This function only supports positive integers')
bytes = long_to_bytes(l)
if ord(bytes[0]) > 127:
return '\x00' + bytes
else:
return bytes
def pkcs_i2osp(x,xLen):
"""
Converts a long (the first parameter) to the associated byte string
representation of length l (second parameter). Basically, the length
parameters allow the function to perform the associated padding.
Input : x nonnegative integer to be converted
xLen intended length of the resulting octet string
Output: x corresponding nonnegative integer
Reverse function is pkcs_os2ip().
"""
z = number.long_to_bytes(x)
padlen = max(0, xLen-len(z))
return '\x00'*padlen + z
# for every hash function a tuple is provided, giving access to
# - hash output length in byte
# - associated hash function that take data to be hashed as parameter
# XXX I do not provide update() at the moment.
# - DER encoding of the leading bits of digestInfo (the hash value
# will be concatenated to create the complete digestInfo).
#
# Notes:
# - MD4 asn.1 value should be verified. Also, as stated in
# PKCS#1 v2.1, MD4 should not be used.
# - hashlib is available from http://code.krypto.org/python/hashlib/
# - 'tls' one is the concatenation of both md5 and sha1 hashes used
# by SSL/TLS when signing/verifying things
def pkcs_i2osp(x,xLen):
"""
Converts a long (the first parameter) to the associated byte string
representation of length l (second parameter). Basically, the length
parameters allow the function to perform the associated padding.
Input : x nonnegative integer to be converted
xLen intended length of the resulting octet string
Output: x corresponding nonnegative integer
Reverse function is pkcs_os2ip().
"""
z = number.long_to_bytes(x)
padlen = max(0, xLen-len(z))
return '\x00'*padlen + z
# for every hash function a tuple is provided, giving access to
# - hash output length in byte
# - associated hash function that take data to be hashed as parameter
# XXX I do not provide update() at the moment.
# - DER encoding of the leading bits of digestInfo (the hash value
# will be concatenated to create the complete digestInfo).
#
# Notes:
# - MD4 asn.1 value should be verified. Also, as stated in
# PKCS#1 v2.1, MD4 should not be used.
# - hashlib is available from http://code.krypto.org/python/hashlib/
# - 'tls' one is the concatenation of both md5 and sha1 hashes used
# by SSL/TLS when signing/verifying things
def MGF1(mgfSeed, maskLen, hash):
"""Mask Generation Function, described in B.2.1"""
T = b("")
for counter in xrange(ceil_div(maskLen, hash.digest_size)):
c = long_to_bytes(counter, 4)
T = T + hash.new(mgfSeed + c).digest()
assert(len(T)>=maskLen)
return T[:maskLen]
def _lengthOctets(self, payloadLen):
"""Return a byte string that encodes the given payload length (in
bytes) in a format suitable for a DER length tag (L).
"""
if payloadLen>127:
encoding = long_to_bytes(payloadLen)
return bchr(len(encoding)+128) + encoding
return bchr(payloadLen)
def encode(self):
"""Return a complete INTEGER DER element, fully encoded as a TLV."""
self.payload = long_to_bytes(self.value)
if bord(self.payload[0])>127:
self.payload = bchr(0x00) + self.payload
return DerObject.encode(self)
def MGF1(mgfSeed, maskLen, hash):
"""Mask Generation Function, described in B.2.1"""
T = b("")
for counter in range(ceil_div(maskLen, hash.digest_size)):
c = long_to_bytes(counter, 4)
T = T + hash.new(mgfSeed + c).digest()
assert(len(T)>=maskLen)
return T[:maskLen]
def _lengthOctets(self, payloadLen):
"""Return a byte string that encodes the given payload length (in
bytes) in a format suitable for a DER length tag (L).
"""
if payloadLen>127:
encoding = long_to_bytes(payloadLen)
return bchr(len(encoding)+128) + encoding
return bchr(payloadLen)
def encode(self):
"""Return a complete INTEGER DER element, fully encoded as a TLV."""
self.payload = long_to_bytes(self.value)
if bord(self.payload[0])>127:
self.payload = bchr(0x00) + self.payload
return DerObject.encode(self)
def pkcs_i2osp(x,xLen):
"""
Converts a long (the first parameter) to the associated byte string
representation of length l (second parameter). Basically, the length
parameters allow the function to perform the associated padding.
Input : x nonnegative integer to be converted
xLen intended length of the resulting octet string
Output: x corresponding nonnegative integer
Reverse function is pkcs_os2ip().
"""
z = number.long_to_bytes(x)
padlen = max(0, xLen-len(z))
return '\x00'*padlen + z
# for every hash function a tuple is provided, giving access to
# - hash output length in byte
# - associated hash function that take data to be hashed as parameter
# XXX I do not provide update() at the moment.
# - DER encoding of the leading bits of digestInfo (the hash value
# will be concatenated to create the complete digestInfo).
#
# Notes:
# - MD4 asn.1 value should be verified. Also, as stated in
# PKCS#1 v2.1, MD4 should not be used.
# - hashlib is available from http://code.krypto.org/python/hashlib/
# - 'tls' one is the concatenation of both md5 and sha1 hashes used
# by SSL/TLS when signing/verifying things
def MGF1(mgfSeed, maskLen, hash):
"""Mask Generation Function, described in B.2.1"""
T = b("")
for counter in xrange(ceil_div(maskLen, hash.digest_size)):
c = long_to_bytes(counter, 4)
T = T + hash.new(mgfSeed + c).digest()
assert(len(T)>=maskLen)
return T[:maskLen]
def _lengthOctets(self, payloadLen):
"""Return a byte string that encodes the given payload length (in
bytes) in a format suitable for a DER length tag (L).
"""
if payloadLen>127:
encoding = long_to_bytes(payloadLen)
return bchr(len(encoding)+128) + encoding
return bchr(payloadLen)
