def verify(public_key, message, signature, hash_class=hashlib.sha1):
'''Verify a signature of a message using a RSA public key and PKCS#1.5
padding.
Parameters:
public_key - a RSA public key
message - the signed string
signature - the signature string
Result:
True if the signature matches the message, False otherwise.
'''
if len(signature) != public_key.byte_size:
raise exceptions.InvalidSignature
s = primitives.os2ip(signature)
try:
m = public_key.rsavp1(s)
except ValueError:
raise exceptions.InvalidSignature
try:
em = primitives.i2osp(m, public_key.byte_size)
except ValueError:
raise exceptions.InvalidSignature
try:
em_prime = emsa_pkcs1_v15.encode(message, public_key.byte_size,
hash_class=hash_class)
except ValueError:
raise exceptions.RSAModulusTooShort
return primitives.constant_time_cmp(em, em_prime)
def verify(public_key, message, signature):
'''Verify a signature of a message using a RSA public key and PKCS#1.5
padding.
Parameters:
public_key - a RSA public key
message - the signed string
signature - the signature string
Result:
True if the signature matches the message, False otherwise.
'''
if len(signature) != public_key.byte_size:
raise exceptions.InvalidSignature
s = primitives.os2ip(signature)
try:
m = public_key.rsavp1(s)
except ValueError:
raise exceptions.InvalidSignature
try:
em = primitives.i2osp(m, public_key.byte_size)
except ValueError:
raise exceptions.InvalidSignature
try:
em_prime = emsa_pkcs1_v15.encode(message, public_key.byte_size)
except ValueError:
raise exceptions.RSAModulusTooShort
return primitives.constant_time_cmp(em, em_prime)
def sign(private_key, message):
'''Produce a signature of string using a RSA private key and PKCS#1.5
padding.
Parameters:
private_key - a RSA private key
message - a string to sign
Result:
the signature string
'''
em = emsa_pkcs1_v15.encode(message, private_key.byte_size)
m = primitives.os2ip(em)
s = private_key.rsasp1(m)
return primitives.i2osp(s, private_key.byte_size)
def sign(private_key, message, hash_class=hashlib.sha1):
'''Produce a signature of string using a RSA private key and PKCS#1.5
padding.
Parameters:
private_key - a RSA private key
message - a string to sign
Result:
the signature string
'''
em = emsa_pkcs1_v15.encode(message, private_key.byte_size,
hash_class=hash_class)
m = primitives.os2ip(em)
s = private_key.rsasp1(m)
return primitives.i2osp(s, private_key.byte_size)
