oxident
08-04-2012, 03:58 AM
Hi!
I'm making huge progress in learning IDA and I'm already able to break simple protections but one thing remains unclear to me:
If I need to alter the control flow of a target (by changing JZs to JMPs for example) I still haven't figured out how to do this easily within IDA. I know that I can use the "Patch"->"Assemble" command but whenever I try to use it, the resulting opcodes won't fit.
If I need to change an instruction like JNZ short loc_xyz to JZ short loc_xyz, IDA always translates this to a near or far jump, resulting in a bigger instruction and therefore overwriting subsequent instructions :-(
Does anyone know what I'm missing here?
Thanks!
I'm making huge progress in learning IDA and I'm already able to break simple protections but one thing remains unclear to me:
If I need to alter the control flow of a target (by changing JZs to JMPs for example) I still haven't figured out how to do this easily within IDA. I know that I can use the "Patch"->"Assemble" command but whenever I try to use it, the resulting opcodes won't fit.
If I need to change an instruction like JNZ short loc_xyz to JZ short loc_xyz, IDA always translates this to a near or far jump, resulting in a bigger instruction and therefore overwriting subsequent instructions :-(
Does anyone know what I'm missing here?
Thanks!