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Trying to use PyCryptodome AES ECB decryption with offsets

As a bit of context to this I am converting a java file to python and am on the last operation. I'm at about 200 LOC so it makes it that much more edge of the seat...
Anyways, in java the operation is:
Cipher cipher = Cipher.getInstance("AES/ecb/nopadding");
cipher.init(Cipher.DECRYPT_MODE, new SecretKeySpec(keys[i], "AES"));
//doFinal(byte[] input, int inputOffset, int inputLen, byte[] output, int outputOffset)
cipher.doFinal(save, saveOffset, 16, save, saveOffset);
In python I have this:
from Crypto.Cipher import AES
cipher = AES.new(bytes(keys[i]), AES.MODE_ECB)
cipher.decrypt(?????)
This is taken from the package under decrypt():
:Parameters:
ciphertext : bytes/bytearray/memoryview
The piece of data to decrypt.
The length must be multiple of the cipher block length.
:Keywords:
output : bytearray/memoryview
The location where the plaintext must be written to.
If ``None``, the plaintext is returned.
:Return:
If ``output`` is ``None``, the plaintext is returned as ``bytes``.
Otherwise, ``None``.
As you can see .decrypt() doesn't really have an input for offsets, but I was wondering if there was some way around this?
This is why I decided to post on SO, would I be able to send:
temp_bytes = save[offset]
temp_decrypt = cipher.decrypt(temp_bytes)
save[offset] = temp_decrypt
Or when decrypting does it use the whole file as context and i will get the wrong output? I would love to just do it and test it but the output is just gibberish that i will have to write another program to parse (another java to python project).

What ended up working was:
save[saveOffset:saveOffset+16] = cipher.decrypt(save[saveOffset:saveOffset+16])
Did not expect it to work so easily

How to decrypt encrypted String in C# but encrypted in java (jasypt)

i need to decrypt the encrypted string in MsSQl. the encrypted String is encrypted using jasypt as i have the source code (java)
my problem is, i cannot decrypt back the encrypted string in C#.
this is the code used in java:
public String encrypt(String strClearText){
String strKey="password";
StandardPBEStringEncryptor encryptor = new StandardPBEStringEncryptor();
encryptor.setPassword(strKey);
String encrypted= encryptor.encrypt(strClearText);
return encrypted;
}
I try to convert the jasypt.jar to dll using ikvm and still no luck.
Is there any way i can do to overcome this problem? so that the encrypted password can be use in java and also in c#?
i cannot change the method of encryption as this encrypted String is being used by many other software. i hope you guys can tell me/teach me another way to overcome this problem..
Thank you :)

Android AES encryption secret key

I'm developping an Android app and i wanna do encryption with AES-128.
I use secret key and text with hexadecimal.
I use this website : http://testprotect.com/appendix/AEScalc to compute the AES encryption with the following key : "c4dcc3c6ce0acaec4327b6098260b0be" and my text to encrypt is : "6F4B1B252A5F0C3F2992E1A65E56E5B8" (hexadecimal).
So the result from this website give me "859499d0802de8cc6ba4f208da648a8f" and that's the result i wanna get.
http://hpics.li/d89105a
I find some code on the net, but a lot uses seed to generate random secret key and i wanna fix the secret key.
Actually i'm using the following code, i think it's the code i need but the result gives me D/resultdebug: 72adc67b6d11e1c5fb89ddf5faeb0e030686b91f8bfaf6c41335f08955343f87
and it's not the same result than the website, that i want.
String text16 = "6F4B1B252A5F0C3F2992E1A65E56E5B8";
String secret16 = "c4dcc3c6ce0acaec4327b6098260b0be";
SecretKeySpec sks = new SecretKeySpec(secret16.getBytes(),"AES");
Cipher c = Cipher.getInstance("AES");
c.init(Cipher.ENCRYPT_MODE, sks);
c.update(text16.getBytes());
byte[] ciphertext = c.doFinal();
Log.d("resultdebug",new String(Hex.encode(ciphertext), "ASCII"));
Could you please tell me what's wrong, thanks.

You are not converting the hex to binary, you are getting the binary of the characters not the value that is hex encoded.

Thanks zaph, it solved my problem
I added these two lines on my code :
byte[] text = stringhextobyte(text16);
byte[] secret = stringhextobyte(secret16);
And the function stringhextobyte permit me to transform my hex string to byte array and i get the result needed.

Encrypt in java, decrypt in node.js

I need to encrypt in java and decrypt with node.js. The decryption result is corrupted.
Here is the java code:
public String encrypt(SecretKey key, String message){
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, key);
byte[] stringBytes = message.getBytes("UTF8");
byte[] raw = cipher.doFinal(stringBytes);
// converts to base64 for easier display.
BASE64Encoder encoder = new BASE64Encoder();
String base64 = encoder.encode(raw);
return base64;
}
Here is the node.js code:
AEse3SCrypt.decrypt = function(cryptkey, encryptdata) {
encryptdata = new Buffer(encryptdata, 'base64').toString('binary');
var decipher = crypto.createDecipher('aes-128-cbc', cryptkey);
decipher.setAutoPadding(false);
var decoded = decipher.update(encryptdata);
decoded += decipher.final();
return decoded;
}
As a key I use: "[B#4ec6948c"
The jave encrypted result is: "dfGiiHZi8wYBnDetNhneBw=="<br>
The node.js result is garbich....
In java I use "PKCS5Padding". What should be done in node.js regarding padding? I made setAutoPadding(false). If I don't do it I get error decipher fail. (only from node.js version 0.8).
I tried to remove utf8 encoding from the java in order to be complementary with the node.js but it didn't work.
Any idea what is wrong?

As a key I use: "[B#4ec6948c"
That sounds very much like you're just calling toString() on a byte array. That's not giving you the data within the byte array - it's just the default implementation of Object.toString(), called on a byte array.
Try using Arrays.toString(key) to print out the key.
If you were using that broken key value in the node.js code, it's no wonder it's giving you garbage back.
I tried to remove utf8 encoding from the java in order to be complementary with the node.js
That's absolutely the wrong approach. Instead, you should work out how to make the node.js code interpret the plaintext data as UTF-8 encoded text. Fundamentally, strings are character data and encryption acts on binary data - you need a way to bridge the gap, and UTF-8 is an entirely reasonable way of doing so. The initial result of the decryption in node.js should be binary data, which you then "decode" to text via UTF-8.
I'm afraid I don't know enough about the padding side to comment on that.

Problems encoding/decoding using AES-128-CBC

So basically I have these snippets of code and would like them to produce the same output:
require 'openssl'
aes = OpenSSL::Cipher::Cipher.new("AES-128-CBC")
aes.key = "aaaaaaaaaaaaaaaa"
aes.iv = "aaaaaaaaaaaaaaaa"
aes.encrypt
encrypted = aes.update("1234567890123456") << aes.final
puts encrypted.unpack('H*').join
This prints:
8d3bbffade308f8e4e80cb77ecb8df19ee933f75438cec1315c4a491bd1b83f4
And this Java code:
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
String key = "aaaaaaaaaaaaaaaa";
String textToEncryptpt = "1234567890123456";
SecretKeySpec keyspec = new SecretKeySpec(key.getBytes(), "AES");
IvParameterSpec ivspec = new IvParameterSpec(key.getBytes());
cipher.init(Cipher.ENCRYPT_MODE, keyspec, ivspec);
byte[] encrypted = cipher.doFinal(textToEncryptpt.getBytes());
System.out.println(Crypto.bytesToHex(encrypted));
Prints:
2d3760f53b8b3dee722aed83224f418f9dd70e089ecfe9dc689147cfe0927ddb
Annoying thing is that it was working a couple of days ago... so I am not sure what happened. What's wrong with this code? Do you see anything unusual?

Ruby script is wrong. You have to first call the encrypt method, and then set the key and iv:
require 'openssl'
aes = OpenSSL::Cipher::Cipher.new("AES-128-CBC")
aes.encrypt
aes.key = "aaaaaaaaaaaaaaaa"
aes.iv = "aaaaaaaaaaaaaaaa"
encrypted = aes.update("1234567890123456") << aes.final
puts encrypted.unpack('H*').join
I figured out because when trying to decode an encrypted string I got:
aescrypt.rb:13:in `final': bad decrypt (OpenSSL::Cipher::CipherError)
from aescrypt.rb:13:in `<main>'

Seems you found already the reason that your script does give different results.
Some more things to consider:
Don't ever hardcode the key in the program - that way you can't easily change it, and if someone gets access to your program code, she also gets to see the key.
Don't ever use a constant initialization vector. Instead, generate a random one and send it together with the ciphertext. Alternatively, if you generate the key from a password and some salt, you can also generate the IV from the same ... but don't use the key directly as IV.
Your key/IV values are strings, not bytes. String.getBytes() (in Java) converts the string to bytes using some encoding. The encoding used is system-dependent, and none of the usual String encodings (UTF-8, Latin-1, ...) can represent all bytes as printable (and typeable) characters. Preferably use something like Base64 or hex-encoding, if you have to store your key as string.
And whenever you transform a string to bytes, specify an encoding (and use the same encoding later for retrieving it).

#Cristian, For key and initial vector, you can create a function by using today's date plus the secure fixed keyword.
Eg: key = January 8, 2012 + Key
And for initial vector,
Eg: iv = January 8, 2012 + IV
Then enter that data(key and iv) to MD5 it will produce the output 16 bytes that you can use for the Key and IV. Every day, key and iv will change randomly.
Make sure both systems use the same date format and setup on the same date.