/usr/share/pyshared/tlslite/utils/RSAKey.py is in python-tlslite 0.3.8-1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 | """Abstract class for RSA."""
from cryptomath import *
class RSAKey:
"""This is an abstract base class for RSA keys.
Particular implementations of RSA keys, such as
L{OpenSSL_RSAKey.OpenSSL_RSAKey},
L{Python_RSAKey.Python_RSAKey}, and
L{PyCrypto_RSAKey.PyCrypto_RSAKey},
inherit from this.
To create or parse an RSA key, don't use one of these classes
directly. Instead, use the factory functions in
L{tlslite.utils.keyfactory}.
"""
def __init__(self, n=0, e=0):
"""Create a new RSA key.
If n and e are passed in, the new key will be initialized.
@type n: int
@param n: RSA modulus.
@type e: int
@param e: RSA public exponent.
"""
raise NotImplementedError()
def __len__(self):
"""Return the length of this key in bits.
@rtype: int
"""
return numBits(self.n)
def hasPrivateKey(self):
"""Return whether or not this key has a private component.
@rtype: bool
"""
raise NotImplementedError()
def hash(self):
"""Return the cryptoID <keyHash> value corresponding to this
key.
@rtype: str
"""
raise NotImplementedError()
def getSigningAlgorithm(self):
"""Return the cryptoID sigAlgo value corresponding to this key.
@rtype: str
"""
return "pkcs1-sha1"
def hashAndSign(self, bytes):
"""Hash and sign the passed-in bytes.
This requires the key to have a private component. It performs
a PKCS1-SHA1 signature on the passed-in data.
@type bytes: str or L{array.array} of unsigned bytes
@param bytes: The value which will be hashed and signed.
@rtype: L{array.array} of unsigned bytes.
@return: A PKCS1-SHA1 signature on the passed-in data.
"""
if not isinstance(bytes, type("")):
bytes = bytesToString(bytes)
hashBytes = stringToBytes(sha.sha(bytes).digest())
prefixedHashBytes = self._addPKCS1SHA1Prefix(hashBytes)
sigBytes = self.sign(prefixedHashBytes)
return sigBytes
def hashAndVerify(self, sigBytes, bytes):
"""Hash and verify the passed-in bytes with the signature.
This verifies a PKCS1-SHA1 signature on the passed-in data.
@type sigBytes: L{array.array} of unsigned bytes
@param sigBytes: A PKCS1-SHA1 signature.
@type bytes: str or L{array.array} of unsigned bytes
@param bytes: The value which will be hashed and verified.
@rtype: bool
@return: Whether the signature matches the passed-in data.
"""
if not isinstance(bytes, type("")):
bytes = bytesToString(bytes)
hashBytes = stringToBytes(sha.sha(bytes).digest())
prefixedHashBytes = self._addPKCS1SHA1Prefix(hashBytes)
return self.verify(sigBytes, prefixedHashBytes)
def sign(self, bytes):
"""Sign the passed-in bytes.
This requires the key to have a private component. It performs
a PKCS1 signature on the passed-in data.
@type bytes: L{array.array} of unsigned bytes
@param bytes: The value which will be signed.
@rtype: L{array.array} of unsigned bytes.
@return: A PKCS1 signature on the passed-in data.
"""
if not self.hasPrivateKey():
raise AssertionError()
paddedBytes = self._addPKCS1Padding(bytes, 1)
m = bytesToNumber(paddedBytes)
if m >= self.n:
raise ValueError()
c = self._rawPrivateKeyOp(m)
sigBytes = numberToBytes(c)
return sigBytes
def verify(self, sigBytes, bytes):
"""Verify the passed-in bytes with the signature.
This verifies a PKCS1 signature on the passed-in data.
@type sigBytes: L{array.array} of unsigned bytes
@param sigBytes: A PKCS1 signature.
@type bytes: L{array.array} of unsigned bytes
@param bytes: The value which will be verified.
@rtype: bool
@return: Whether the signature matches the passed-in data.
"""
paddedBytes = self._addPKCS1Padding(bytes, 1)
c = bytesToNumber(sigBytes)
if c >= self.n:
return False
m = self._rawPublicKeyOp(c)
checkBytes = numberToBytes(m)
return checkBytes == paddedBytes
def encrypt(self, bytes):
"""Encrypt the passed-in bytes.
This performs PKCS1 encryption of the passed-in data.
@type bytes: L{array.array} of unsigned bytes
@param bytes: The value which will be encrypted.
@rtype: L{array.array} of unsigned bytes.
@return: A PKCS1 encryption of the passed-in data.
"""
paddedBytes = self._addPKCS1Padding(bytes, 2)
m = bytesToNumber(paddedBytes)
if m >= self.n:
raise ValueError()
c = self._rawPublicKeyOp(m)
encBytes = numberToBytes(c)
return encBytes
def decrypt(self, encBytes):
"""Decrypt the passed-in bytes.
This requires the key to have a private component. It performs
PKCS1 decryption of the passed-in data.
@type encBytes: L{array.array} of unsigned bytes
@param encBytes: The value which will be decrypted.
@rtype: L{array.array} of unsigned bytes or None.
@return: A PKCS1 decryption of the passed-in data or None if
the data is not properly formatted.
"""
if not self.hasPrivateKey():
raise AssertionError()
c = bytesToNumber(encBytes)
if c >= self.n:
return None
m = self._rawPrivateKeyOp(c)
decBytes = numberToBytes(m)
if (len(decBytes) != numBytes(self.n)-1): #Check first byte
return None
if decBytes[0] != 2: #Check second byte
return None
for x in range(len(decBytes)-1): #Scan through for zero separator
if decBytes[x]== 0:
break
else:
return None
return decBytes[x+1:] #Return everything after the separator
def _rawPrivateKeyOp(self, m):
raise NotImplementedError()
def _rawPublicKeyOp(self, c):
raise NotImplementedError()
def acceptsPassword(self):
"""Return True if the write() method accepts a password for use
in encrypting the private key.
@rtype: bool
"""
raise NotImplementedError()
def write(self, password=None):
"""Return a string containing the key.
@rtype: str
@return: A string describing the key, in whichever format (PEM
or XML) is native to the implementation.
"""
raise NotImplementedError()
def writeXMLPublicKey(self, indent=''):
"""Return a string containing the key.
@rtype: str
@return: A string describing the public key, in XML format.
"""
return Python_RSAKey(self.n, self.e).write(indent)
def generate(bits):
"""Generate a new key with the specified bit length.
@rtype: L{tlslite.utils.RSAKey.RSAKey}
"""
raise NotImplementedError()
generate = staticmethod(generate)
# **************************************************************************
# Helper Functions for RSA Keys
# **************************************************************************
def _addPKCS1SHA1Prefix(self, bytes):
prefixBytes = createByteArraySequence(\
[48,33,48,9,6,5,43,14,3,2,26,5,0,4,20])
prefixedBytes = prefixBytes + bytes
return prefixedBytes
def _addPKCS1Padding(self, bytes, blockType):
padLength = (numBytes(self.n) - (len(bytes)+3))
if blockType == 1: #Signature padding
pad = [0xFF] * padLength
elif blockType == 2: #Encryption padding
pad = createByteArraySequence([])
while len(pad) < padLength:
padBytes = getRandomBytes(padLength * 2)
pad = [b for b in padBytes if b != 0]
pad = pad[:padLength]
else:
raise AssertionError()
#NOTE: To be proper, we should add [0,blockType]. However,
#the zero is lost when the returned padding is converted
#to a number, so we don't even bother with it. Also,
#adding it would cause a misalignment in verify()
padding = createByteArraySequence([blockType] + pad + [0])
paddedBytes = padding + bytes
return paddedBytes
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