Speaker 1: Welcome to our deep dive into reverse engineering with IDA pro.
Speaker 1: You sent over some excerpts from the IDA pro book. Yeah,
Speaker 1: so it looks like you're ready to really get into
Speaker 1: the nuts and bolts of software.
Speaker 2: Absolutely. Yeah, it's a whole world where we kind of
Speaker 2: get to look under the hood and see how things
Speaker 2: actually work.
Speaker 1: I've always wondered, like who uses IDA pro.
Speaker 2: You know, it's used by like security researchers obviously, you know,
Speaker 2: analyzing malware and things like that, but also like software engineers,
Speaker 2: Oh wow, who have to deal with legacy code and
Speaker 2: they need to update something or figure out how something works.
Speaker 1: So when you say like figure out how something works,
Speaker 1: what does that actually mean? What's IDA pro doing?
Speaker 2: Well, you know, computers run on machine code, which is
Speaker 2: just ones and zeros, right, and that's not very human readable.
Speaker 2: So ida pro takes those ones and zeros and turns
Speaker 2: them into assembly language, which is a little more human readable.
Speaker 1: Okay, So it's like a translator yeah, exactly between computer
Speaker 1: and something we can at least try to understand.
Speaker 2: And it stores all that information in a database that
Speaker 2: you can work with, which is in dot IDB file
Speaker 2: and you don't even need the original program to look
Speaker 2: at the analysis after that.
Speaker 1: So backing up a little bit, how does IDA pro
Speaker 1: even know what kind of file it's looking at? I
Speaker 1: mean a lot of times you can't tell by the
Speaker 1: file extension.
Speaker 2: Yeah, you can't go by file extensions, you know, it's
Speaker 2: very surface level. You need to look at the actual
Speaker 2: contents of the file.
Speaker 1: So it's like more than just judging a book by
Speaker 1: its cover. It's actually looking inside and kind of getting
Speaker 1: a fingerprint.
Speaker 2: It uses things called magic numbers, which are like digital
Speaker 2: fingerprints that tell you what type of file it is.
Speaker 1: So once you know what you're looking at, what are
Speaker 1: some of the things that IDA can do well.
Speaker 2: It can identify like standard library routines that a lot
Speaker 2: of programs use, okay, and by identifying those, you can
Speaker 2: kind of like skip over those parts and look at
Speaker 2: the more unique parts of the code.
Speaker 1: So it's kind of like if you were reading a book,
Speaker 1: you could skip the chapters that are the same in
Speaker 1: every book, yeah, exactly, and get to the good stuff.
Speaker 2: It can also do things like visualized code as graphs,
Speaker 2: so you can see like a map of how the
Speaker 2: program flows. Wow, all the different paths it can take.
Speaker 1: That's got to be really helpful, especially for like more
Speaker 1: complicated code.
Speaker 2: Yeah, and you know, you can even extend IDA to
Speaker 2: support new processors, processors that haven't even been invented yet.
Speaker 1: So okay, we've talked about what it can do, but
Speaker 1: what does it actually look like when you're using IDA pro.
Speaker 2: Well, when you open it up, you see like a
Speaker 2: multi windowed interface. Okay, it might seem a little overwhelming
Speaker 2: at first, but each window serves a specific purpose.
Speaker 1: Okay, So you have like different tools.
Speaker 2: In there, yeah, exactly. Like you have the graph view,
Speaker 2: which we talked about right, shows the code flow. There's
Speaker 2: the text view, which shows the disassemble code line by line.
Speaker 1: It's a lot of different ways to look at it. Yeah.
Speaker 2: You have the functions window, which lists all the functions
Speaker 2: that it's identified in the program.
Speaker 1: And then you have the output window.
Speaker 2: Yeah, the output window which shows you messages from idea,
Speaker 2: and the strings window, which is really useful for finding
Speaker 2: like human reatable text.
Speaker 1: So you have to kind of know how to navigate
Speaker 1: all those different windows. Yeah.
Speaker 2: Absolutely, it's actually designed to be pretty intuitive. You can
Speaker 2: jump to certain addresses in the code, okay. You can
Speaker 2: use like the navigation history like a web browser.
Speaker 1: So you can go back.
Speaker 2: Yeah, and you can follow like cross references, which are
Speaker 2: like links between different parts of the code, so.
Speaker 1: Like a map and a compass for software.
Speaker 2: Exactly.
Speaker 1: All right, well let's talk about those instructions. So I imagine
Speaker 1: it's like steps in a recipe or something.
Speaker 2: Yeah. Some instructions are just executed sequentially, one after the other,
Speaker 2: like a recipe, right, But other instructions can introduce like branching.
Speaker 1: So the program can go in different directions.
Speaker 2: Yeah, exactly. It's called conditional branching.
Speaker 1: An idea pro can can help you look at all
Speaker 1: those different paths. Yeah.
Speaker 2: It disassembles both paths of a branch, so you can
Speaker 2: see like all the potential flows of execution.
Speaker 1: And then you have function calls, which are like mini
Speaker 1: programs within the bigger program. Yeah exactly, So that can
Speaker 1: get really complicated.
Speaker 2: You know, understanding how those function calls work is really
Speaker 2: crucial for understanding the logic of a program.
Speaker 1: So how do these functions communicate with each other?
Speaker 2: Well, that's where calling conventions come in. They're like the
Speaker 2: rules of etiquette for how functions talk to each other.
Speaker 1: So why is it important to understand the calling conventions?
Speaker 2: Because if you don't understand the rules of communication, then
Speaker 2: you're not going to understand what the code is doing.
Speaker 2: It's like trying to understand a foreign language without knowing
Speaker 2: the grammar.
Speaker 1: Okay. And so there are different types of calling conventions.
Speaker 2: Yeah, Like common ones are sedical and SETI.
Speaker 1: Call, and id pro can help you understand which calling
Speaker 1: convention is being used.
Speaker 2: Yeah, it gives you clues and helps you decipher it.
Speaker 1: But it's hard to keep track of all that data
Speaker 1: moving between these functions.
Speaker 2: Well, that's where stack frames come in. Each function has
Speaker 2: like a little workspace and memory where it stores its
Speaker 2: local variables and parameters and things like that.
Speaker 1: So it's like its own little office exactly.
Speaker 2: And ida pro lets you view those stack frames and
Speaker 2: even modify them.
Speaker 1: Wow, this is getting really complicated.
Speaker 2: Yeah, but he's pretty powerful.
Speaker 1: I'm hooked. I want to learn more.
Speaker 2: All right, let's get good. So we've been talking about code,
Speaker 2: but what about data. How does ida pro handle the data?
Speaker 1: Yeah, because it's not just about the instructions, right, it's
Speaker 1: about how the program actually uses data exactly.
Speaker 2: Yeah, have the instructions like the verbs, but you need
Speaker 2: the nouns to understand what's going on. So ida pro
Speaker 2: goes beyond just showing you a bunch of raw bites.
Speaker 1: Oh okay.
Speaker 2: It lets you define data types, erase structures, all kinds
Speaker 2: of things.
Speaker 1: Wait, structures, what are those?
Speaker 2: Well, imagine you have a program that's storing information about people.
Speaker 2: Each person has a name and age, an address.
Speaker 1: Okay.
Speaker 2: A structure lets you group all that data together under
Speaker 2: one name.
Speaker 1: So instead of seeing just a bunch of variables, you
Speaker 1: see like a person with information.
Speaker 2: And ida pro lets you create and apply these structures
Speaker 2: to make the disassembly much more readable.
Speaker 1: Oh that's cool. Yeah, especially if you're working with some
Speaker 1: kind of complex data format.
Speaker 2: Yeah, and remember those type libraries we talked about. Those
Speaker 2: come in hand and here too, because id pro has
Speaker 2: these libraries that define standard data structures.
Speaker 1: So it's like a reference guide yeah for a data format.
Speaker 2: So it can often automatically recognize and apply these structures
Speaker 2: for you.
Speaker 1: Well that's awesome. Saves you a lot of time.
Speaker 2: And once you have the code and the data well defined,
Speaker 2: you can start to see the bigger picture. Okay, this
Speaker 2: is where idpro's graphing capabilities come in.
Speaker 1: The graphs, right, Why are these so important again?
Speaker 2: Well, they give you a visual representation of the relationships
Speaker 2: between different parts of the program. They can show you
Speaker 2: how code flows within a function, how functions call each other,
Speaker 2: how data.
Speaker 1: Is accessed, so it's like a map of the software exactly.
Speaker 2: And there are two main types of graphs.
Speaker 1: Okay.
Speaker 2: You have external graphs, which use separate graphing applications, and
Speaker 2: then you have integrated graphs, which are built right into
Speaker 2: IDA so.
Speaker 1: You don't have to leave id pro.
Speaker 2: Yeah, exactly. And the integrated graphs are really cool because
Speaker 2: they're interactive.
Speaker 1: What does that mean.
Speaker 2: Well, you can zoom in and out, you can pan around,
Speaker 2: you can click on different nodes in the graph to
Speaker 2: jump to.
Speaker 1: The corresponding kind Oh that's awesome.
Speaker 2: It makes it much more engaging to understand the structure
Speaker 2: of the program.
Speaker 1: And there were different types of graphs, right, yeah, like
Speaker 1: flow chart graphs. Those show the flow of the program.
Speaker 2: Yeah, the flow of execution within a function, okay. And
Speaker 2: then you have call graphs, which show you the hierarchy
Speaker 2: of function calls, like who calls who exactly.
Speaker 1: So it seems like there's a lot of customization that
Speaker 1: you can do in IDA pro.
Speaker 2: Yeah. Absolutely.
Speaker 1: Yeah.
Speaker 2: One of the first things you want to look at
Speaker 2: is the configuration options. You can customize like the font,
Speaker 2: the colors, keyboard shortcuts, all kinds of.
Speaker 1: Things, so you can make it work the way you
Speaker 1: want it to exactly.
Speaker 2: And then if you want to go even further, you
Speaker 2: can use ida Pro's scripting language IDC.
Speaker 1: I've heard about IDC scripting, but like, what can you
Speaker 1: actually do with it?
Speaker 2: Oh? All kinds of things. Let's say you're analyzing a
Speaker 2: program that uses a custom encryption algorithm. You could write
Speaker 2: an IDC script to automatically decrypt the data.
Speaker 1: Oh wow.
Speaker 2: Or you could use it to rename a bunch of
Speaker 2: functions that have like generic names.
Speaker 1: Oh. So it's like you have these little helpers working
Speaker 1: behind the scenes exactly. And you can even go beyond
Speaker 1: IDC scripting with like external plug in.
Speaker 2: Yeah, you can write plugins to add whole new features
Speaker 2: to id pro.
Speaker 1: So it's like you're expanding on its capability exactly. Wow.
Speaker 1: That's a lot.
Speaker 2: But even with all this power, sometimes you need a
Speaker 2: little extra help and that's where FLIRTA comes in.
Speaker 1: FLOORTA What was that again?
Speaker 2: It stands for Fast Library Identification and Recognition Technology.
Speaker 1: Oh okay, I remember you mentioned that.
Speaker 2: It's really helpful because it lets ida pro automatically identify
Speaker 2: standard library functions.
Speaker 1: Why that's so important, Well.
Speaker 2: A lot of programs use common libraries for things like
Speaker 2: string manipulation, map operations.
Speaker 1: Right.
Speaker 2: Without flotaate, you would have to manually analyze those library
Speaker 2: functions every time.
Speaker 1: Oh, that would be tedious.
Speaker 2: Yeah, it would be really time consuming. Yeah, So floirtaate
Speaker 2: basically takes care of that for you, so you.
Speaker 1: Can focus on the interesting parts of the code. Exactly
Speaker 1: how does it even work?
Speaker 2: Well, it uses these things called signature files, which are
Speaker 2: basically databases of function signatures. Okay, and when ideapro loads
Speaker 2: a binary, it compares the code to those signature files.
Speaker 1: So it's like a fingerprint databasect library functions.
Speaker 2: And if it finds a match, it can tell you
Speaker 2: exactly what that function is, what it's calling convention is,
Speaker 2: what parameters it takes.
Speaker 1: That's amazing. So what about when you have custom functions
Speaker 1: or functions with non standard calling conventions? How do you
Speaker 1: deal with those?
Speaker 2: That's where understanding those calling conventions and the stack comes.
Speaker 1: In the calling convention. Those were the rules of etiquette
Speaker 1: right exactly for how functions talk to each other. Yea,
Speaker 1: and the stack was like a temporary workspace exactly.
Speaker 2: So different calling conventions use the stack in different ways.
Speaker 2: Some require the caller to clean up the stack after
Speaker 2: a function call, Others require the function itself to do
Speaker 2: the cleaning.
Speaker 1: So if you don't know which convention's being used, you
Speaker 1: could misinterpret what's happening exactly.
Speaker 2: You might think data is being passed when it's not,
Speaker 2: or you might miss something important about how the function
Speaker 2: is managing its data.
Speaker 1: So you have to know the secret handshake, yeah, for
Speaker 1: each different.
Speaker 2: Function, and idea pro can actually help you figure out
Speaker 2: which handshake is being used. Cool by analyzing the code.
Speaker 1: So how can we see what's happening on the stack
Speaker 1: as the program is running.
Speaker 2: That's where the debugger comes in.
Speaker 1: Oh yeah, the debugger.
Speaker 2: It lets you step through the code one instruction at
Speaker 2: a time, and you can see how data is pushed
Speaker 2: onto the stack and popped off the stack.
Speaker 1: So you can actually see the stack in action.
Speaker 2: Yeah, exactly.
Speaker 1: That's incredible.
Speaker 2: It's a really powerful tool.
Speaker 1: We've covered a lot.
Speaker 2: We've only just scratched the surface of what ideapro can
Speaker 2: do and the techniques that reverse engineers use.
Speaker 1: But this is a good start, right, Yeah.
Speaker 2: Absolutely, it's a great foundation to build upon.
Speaker 1: So we talked about analyzing code and data, you know,
Speaker 1: understanding those functions and how they communicate with each other,
Speaker 1: even using that debugger to step through the program. But
Speaker 1: I imagine like things get even more complicated when developers
Speaker 1: try to make their code hard to understand on purpose.
Speaker 2: Yeah, you're talking about obfuscated code. It's a common tactic,
Speaker 2: especially for like malware authors who want to hide what
Speaker 2: their code is doing.
Speaker 1: So it's like they're trying to make it look like
Speaker 1: a big tangled mess of spaghetti so nobody can figure
Speaker 1: out the recipe.
Speaker 2: Obfuscation techniques can range from simple things like renaming variables
Speaker 2: to more complex things that actually change the structure and
Speaker 2: logic of the code.
Speaker 1: So how do reverse engineers even begin to make sense
Speaker 1: of that? Does IDA pro help with that at all?
Speaker 2: Yeah? It does. The debugger is really helpful here, okay,
Speaker 2: because it lets you step through the code and observe
Speaker 2: its behavior and look for clues about how the obfuscation
Speaker 2: is being applied or removed.
Speaker 1: So it's like peeling back the layers of an onion
Speaker 1: to get to the real code. Underneath.
Speaker 2: And once you've identified those key points in the code
Speaker 2: where the obfuscation is being handled, you can often use
Speaker 2: IDA pro scripting capabilities to automate the deoffuscation process.
Speaker 1: Wow, that's pretty cool.
Speaker 2: Yeah, you can write scripts to like unpack data, decrypt code,
Speaker 2: even emulate the obfuscation routines to get back to the
Speaker 2: original code.
Speaker 1: So you really need to understand both how the obfuscation
Speaker 1: works and how to use IDA pros scripting.
Speaker 2: Yeah, it can be pretty challenging, but it's often necessary
Speaker 2: to understand what the code is really doing, especially if.
Speaker 1: You think it might be malicious. Right, speaking of malicious code,
Speaker 1: you mentioned that IDA pros often used for vulnerability analysis. Yeah,
Speaker 1: can you tell me more about that.
Speaker 2: So a vulnerability is basically a weakness and a piece
Speaker 2: of software that an attacker could exploit to gain unauthorized
Speaker 2: access or control.
Speaker 1: So they're looking for like security holes.
Speaker 2: Exactly, and IDEA pro is a great tool for finding
Speaker 2: and analyzing these vulnerabilities.
Speaker 1: How do they actually use it to find them?
Speaker 2: Well, they use it to dissect the software, looking for
Speaker 2: common coding errors that can lead to vulnerabilities, things like
Speaker 2: buffer overflows where data is written beyond the allocated space
Speaker 2: and memory or form a string vulnerabilities where an attacker
Speaker 2: can manipulate the way data is formatted to gain control
Speaker 2: of the program's execution.
Speaker 1: That sounds pretty complicated, Yeah it is.
Speaker 2: It's a specialized field, but the tools and techniques are
Speaker 2: fundamentally the same as those used for general reverse engineering.
Speaker 1: And you mentioned earlier that IDA pro has a built
Speaker 1: in debugger. Is that used for vulnerability analysis as well?
Speaker 2: Oh? Absolutely, It's invaluable because it allows you to step
Speaker 2: through the code and observe how data is handled and
Speaker 2: identify those potential points of weakness where an attacker might
Speaker 2: be able to inject malicious code or manipulate the program's behavior.
Speaker 1: So again, it's like being a detective looking for clues.
Speaker 2: And one of the most effective techniques for vulnerability analysis
Speaker 2: is called differential analysis. It involves comparing different versions of
Speaker 2: a program, typically a patched version and an unpatched version,
Speaker 2: to see.
Speaker 1: What's changed, So you're looking for the differences.
Speaker 2: Exactly, and by analyzing those differences, security researchers can often
Speaker 2: identify the code that was vulnerable and understand how the
Speaker 2: patch fixed the issue.
Speaker 1: So they can figure out how to protect against attacks. Right,
Speaker 1: that's amazing. It sounds like a constant arms race is
Speaker 1: between the security researchers and the attackers.
Speaker 2: You know, as attackers develop new techniques and exploit new vulnerabilities,
Speaker 2: the defenders have to adapt and develop new countermeasures.
Speaker 1: Well, it's definitely a fascinating field and an important one too. Absolutely,
Speaker 1: we've covered so much ground in this deep dive. We
Speaker 1: have from the basics of reverse engineering to some pretty
Speaker 1: advanced techniques. Yeah, anything else you want to add before
Speaker 1: we wrap up.
Speaker 2: I think we've touched on the most important aspects, But
Speaker 2: I do want to emphasize that this is just the beginning.
Speaker 2: Reverse engineering is a vast and constantly evolving field.
Speaker 1: So there's always more to learn.
Speaker 2: Yeah, always more to learn, new tools and techniques, to
Speaker 2: explore new challenges to tackle.
Speaker 1: It sounds exciting and maybe a little bit daunting.
Speaker 2: It can be both, but IDPro is a really powerful
Speaker 2: and with dedication and a thirst for knowledge, you can
Speaker 2: unlock a lot of the secrets of the digital world.
Speaker 1: Well, I'm definitely inspired to learn more. Thanks for taking
Speaker 1: us on this deep dive into idea pro.
Speaker 2: You're welcome.
Speaker 1: It's been great.
Speaker 2: It's been my pleasure,