Hey, I am having a problem converting ascii hex into actual hex in C.

This is what I am trying to do:
a.out -h 080483c4

I want to turn that hex number that is getting input in ASCII format to be converted into hex format in a character array like this:

myarray[4] : [0xc4][0x83][0x04][0x08] <= little indian

Does anyone know how to do this? I have looked all over and can't find out how. If anyone has a quick answer that would like to share... I appreciate it.

Thanks,
Brandon

First off, it's little endian, not indian.

Second, read it in to a char array as a temp, then use sscanf on it. You can use that to parse out hex numbers (I believe the format is %2x to indicate 2 characters as hex). So it would look something like this (btw, this may not work 100%, this is going off the top of my head without testing it):

argv[2] is assumed to be the 080483c4 read from the command line, since you are passing in variables to main.

char myarray[4];
sscanf(argv[2], "%2x%2x%2x%2x", &myarray[3], &myarray[2], &myarray[1], &myarray[0]);

Thanks Cecil,

You were right on about the sscanf() command and the arguments. I was building a small/simple tool to allow me to easily exploit code vulnerable to stack overflows. I have uploaded the source code for it to my website.

http://web.umr.edu/~bmpfg8/add_of.c

I know you can do some tricks with python at the command line, but I like sticking to good old C and ASM. One thing to note if you are going to test out the code: You need to enter your Hex Address without 0x or 0X. That is something sscanf is suppose to handle... but doesn't (at least it doesn't appear to work for me). It can handle up to a 32bit address.

Thanks again,
Brandon

Well my my, aren't you a l33t h4x0r.

Gay Mother Fucker,

rr... the code I wrote really isn't that "l33t". It is pretty basic.... but anyways... your sarcasm is duely noted.

Thanks,
Brandito