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author | Narayan Desai <desai@mcs.anl.gov> | 2007-03-12 16:22:51 +0000 |
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committer | Narayan Desai <desai@mcs.anl.gov> | 2007-03-12 16:22:51 +0000 |
commit | 6e5e9c8e969207e68665f12665a54768090897e4 (patch) | |
tree | de198777d5041073db4634a24ca37efad2a1017f /src/lib/tlslite/utils/Python_AES.py | |
parent | ac3eb44f16bc14e41ed62169ca36e9992509d7d6 (diff) | |
download | bcfg2-6e5e9c8e969207e68665f12665a54768090897e4.tar.gz bcfg2-6e5e9c8e969207e68665f12665a54768090897e4.tar.bz2 bcfg2-6e5e9c8e969207e68665f12665a54768090897e4.zip |
Merged in certs branch in preparation for 0.9.3pre2
git-svn-id: https://svn.mcs.anl.gov/repos/bcfg/trunk/bcfg2@2928 ce84e21b-d406-0410-9b95-82705330c041
Diffstat (limited to 'src/lib/tlslite/utils/Python_AES.py')
-rwxr-xr-x | src/lib/tlslite/utils/Python_AES.py | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/src/lib/tlslite/utils/Python_AES.py b/src/lib/tlslite/utils/Python_AES.py new file mode 100755 index 000000000..657152f89 --- /dev/null +++ b/src/lib/tlslite/utils/Python_AES.py @@ -0,0 +1,68 @@ +"""Pure-Python AES implementation.""" + +from cryptomath import * + +from AES import * +from rijndael import rijndael + +def new(key, mode, IV): + return Python_AES(key, mode, IV) + +class Python_AES(AES): + def __init__(self, key, mode, IV): + AES.__init__(self, key, mode, IV, "python") + self.rijndael = rijndael(key, 16) + self.IV = IV + + def encrypt(self, plaintext): + AES.encrypt(self, plaintext) + + plaintextBytes = stringToBytes(plaintext) + chainBytes = stringToBytes(self.IV) + + #CBC Mode: For each block... + for x in range(len(plaintextBytes)/16): + + #XOR with the chaining block + blockBytes = plaintextBytes[x*16 : (x*16)+16] + for y in range(16): + blockBytes[y] ^= chainBytes[y] + blockString = bytesToString(blockBytes) + + #Encrypt it + encryptedBytes = stringToBytes(self.rijndael.encrypt(blockString)) + + #Overwrite the input with the output + for y in range(16): + plaintextBytes[(x*16)+y] = encryptedBytes[y] + + #Set the next chaining block + chainBytes = encryptedBytes + + self.IV = bytesToString(chainBytes) + return bytesToString(plaintextBytes) + + def decrypt(self, ciphertext): + AES.decrypt(self, ciphertext) + + ciphertextBytes = stringToBytes(ciphertext) + chainBytes = stringToBytes(self.IV) + + #CBC Mode: For each block... + for x in range(len(ciphertextBytes)/16): + + #Decrypt it + blockBytes = ciphertextBytes[x*16 : (x*16)+16] + blockString = bytesToString(blockBytes) + decryptedBytes = stringToBytes(self.rijndael.decrypt(blockString)) + + #XOR with the chaining block and overwrite the input with output + for y in range(16): + decryptedBytes[y] ^= chainBytes[y] + ciphertextBytes[(x*16)+y] = decryptedBytes[y] + + #Set the next chaining block + chainBytes = blockBytes + + self.IV = bytesToString(chainBytes) + return bytesToString(ciphertextBytes) |