I need to re-sign an IPA file without the source code

Here is my story: 1. I have an IPA file 2. I unzip it and change the version number in its text file. 3. I zip it by 7zip I need to re-sign the IPA file. My friend said " If you just want to change signature in a built Ipa file, it can be done. Using some certificate and provisioning profile." Please read it carefully before offering. Thank you.