How to get identical byte[] in C# and Java

Question

TLDR: Java is signed, c# is unsigned. Byte[] values are different, how to solve this. How can I convert either side to the other?

Values are of "Hello World" MD5 hashed and then converted to bytes

Java:

-79, 10, -115, -79, 100, -32, 117, 65, 5, -73, -87, -101, -25, 46, 63, -27

C#:

177, 10, 141, 177, 100, 224, 117, 65, 5, 183, 169, 155, 231, 46, 63, 229

I use the byte[] to encrypt using AES on both sides but the passwords never match.

Answer 1

The bytes have identical values, they are just printed differently.

If you would like to ensure that bytes with negative values are displayed as positive numbers, add 256 and take modulo 256, like this:

for (byte b : byteArray) {
    int n = (b + 256) % 256;
    System.out.println(n);
}

Similarly, if you would like to bring your values above 128 into the proper range of byte, you can cast them to truncate the upper bytes and get negative values, or if you prefer you could subtract 256:

for (int n : byteValuesAsInt) {
    byte b1 = (byte)n;
    byte b2 = n >= 128 ? n-256 : n;
}