Questions tagged [software-obfuscation]
Software obfuscation is the deliberate act of creating obfuscated code by making source or machine code difficult to understand from a human point of view. This may be by either ad-hoc heuristic techniques, or by cryptographic techniques based on hard problems.
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Can the indistinguishability obfuscator leak the password when obfuscating the password checking function?
Suppose I have a dumb password checking function:
def dumb_checker(password):
return password == "my_secret_key_that_should_not_be_revealed"
One can ...
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Barak et al. proof that black-box obfuscation is impossible
I have been attempting to analyse the classic proof presented by Barak et al. that claims Black-Box Obfuscation is not possible for (what appears to be) most classes of programs.
The proof is ...
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Cryptographic Code Anonymization
I've been reading a lot about techniques related to stylometry whereby programmers can be de-anonymized by analyzing their source code.
Resisting deanonymization seems like a multifaceted problem. ...
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iO from Matrix Branching Programs
Recently I'm learning about constructing iO from Matrix Branching Programs via Multi-linear Maps (to be exact, [GGH+13] and [GGH15]). However, I have a small question that I couldn't figure out.
It ...
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Cryptographic function that can 'pack' numbers
Is there a cryptographic algorithm that can 'pack' a bunch of strings/numbers and "confirm" if a string/numbers exists (later in the code) while keeping the output hidden?
For example, I have ...
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Is obfuscation considered a cryptographic primitive?
The general definition of obfuscation is the process of obscuring a message (not necessarily source code). There is a "rigorous" method for obfuscation (indistinguishability obfuscation, ...
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Ways to make white-box cryptography AES implementation more difficult to be broken
Background: I want to use white-box cryptography to hide the keys stored in a client application.
I am looking for existing implementations of white-box cryptography, such as AES 128 or 256. But I ...
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Is this protocol for masking DB ids sound?
Problem Statement
I don't want to expose my internal database ids (or other internal private ids) so to make it harder to abuse them, by e.g. guessing the next id of a sequence or similar. It is not ...
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Obfuscating functions that are mostly zero
Let $f_k(x)$ be a boolean function of two arguments with two properties:
The function $f$ can be efficiently computed.
The output is always 0 or 1, and for any fixed $k$, if we choose $x$ randomly, $\...
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Is it considered good security to give your variables unhelpful names? [closed]
I was exploring my company's codebase yesterday and I noticed one class which had three variables named m_p1, m_p2, and m_p3. These variables are used very often in this class and each has a different,...
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Are there lower bounds to how efficient one can make obfuscated code?
I am wondering if there are any theoretical reasons why obfuscated programs cannot be nearly as efficient as the plaintext programs and whether there is any necessary computational overhead from ...
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Is obfuscation always reversable?
Let's say we have a program that only accepts numerical inputs and the output is simply an increment by one of the input.
Example with input "a" and output "b":
$$Input: a = 7$$
$$Output: b= a+1 = ...
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Intuitively what makes indistinguishability obfuscation useful?
I am reading some papers about the application of indistinguishability obfuscators (IO). As far as I know, there are two techniques which enables the application of IO: shell game of secrets and ...
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Making brute force attacks less effective through obfuscation?
This page on Wikipedia states
"Brute-force attacks can be made less effective by obfuscating the
data to be encoded making it more difficult for an attacker to
recognize when the code has been ...
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The notion of sub-exponential security
I have been reading a paper where they construct probabilistic IO (indistinguishability obfuscation) from sub exponential IO. I want to know if the following two notions of sub-exponential security ...
user38956
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Sub exponentially hard OWF , PRF and iO
I'm currently reading the work "Obfuscation of probabilistic circuits and Applications' by Canetti Lin Tessaro and Vaikuntanathan 2015. It says sub exponentially hard OWF implies
sub exponentially ...
user38956
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What is Indistinguishability Obfuscation?
I've been studying functional encryption. I recently read that a multi-input functional encryption (MIFE) implies indistinguishability obfuscation (IO).
Can someone please brief me: what is ...
user45080
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Indistinguishability Obfuscation : What are it's consequences on crypto? [closed]
I was reading about the construction of IO using MIFE and compact FE . I am just curious to know what are the consequences if there exists an IO.
user38956
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Why do we use multilinear maps for obfuscation?
I have recently developed interest about obfuscation, and I see that (all?) the proposals use multilinear maps. What's the reason to this? As I also that many of the multilinear map proposals get ...
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Hash based code obfuscation?
The code
if(str1 == "abc") {}
can be converted to
if(hash(str1) == 0x8732e) {} // assume hash("abc") == 0x8732e
to ...
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Does there exist an indistinguishability formal proof obfuscator?
A formal proof obfuscator is a mapping $\mathcal{O}$ such that whenever $P$ is a formal proof of a theorem $T$, then $\mathcal{O}(P)$ is a distribution of formal proofs of the same theorem $T$. An ...
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Do reversible black box obfuscators exist?
We shall say that an obfuscator $\mathcal{O}$ is a reversible black box obfuscator if for each reversible program $P$ the obfuscated program $\mathcal{O}(P)$ is still reversible but does not reveal ...
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Can you have partial cryptographic obfuscation (without a trusted setup)?
Cryptographic Obfuscation is a powerful cryptographic technique. My question is, can you do it partially?
Instead of obfuscating an algorithm completely, you can have an algorithm with a couple of ...
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Why are obfuscators generally defined to be probabilistic algorithms, rather than deterministic ones?
One possible explanation is, randomness is not going to hurt you, so might as well use it. Also, if we are hoping to prove impossibility, it only makes the result stronger.
One other explanation is ...
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What is the state of cryptographic obfuscation in 2015?
Cryptographic Obfuscation is a technique that allows one to obfuscate source code in a secure way (as opposed to insecurely mangling it into spaghetti code.) For example, here is a way to protect a ...
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Obfuscate an "I'll reveal if you do" function
Is there any cryptographic obfuscation scheme that will let me obfuscate a program that reveals my secret, if you reveal yours?
Formalization. Let $C(\cdot),V(\cdot)$ be a secure commitment scheme. ...
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Universal Circuits in Indistinguishability Obfuscation Candidate Construction
I am currently working on an implementation of the candidate construction for an indistinguishability obfuscator that was recently proposed by Garg et al. The relevant paper can be found here. ...
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What functions allow for practical indistinguishability obfuscation?
Recently, there has been a major theoretical breakthrough in program obfuscation, in the area of indistinguishability obfuscation.
Background: Indistinguishability obfuscation is a form of program ...
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Obfuscating point-like functions
There are standard schemes for obfuscating a point function; I'm wondering if we know how to obfuscate a slight generalization of a point function. I'll elaborate more precisely.
Definition 1. A ...
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Digicipher and other proprietary systems?
I've always been curious as to how Pay-TV and other Conditional Access systems actually stay secure for any amount of time, given that they are usually one way and (I'm assuming) use symmetric keys ...
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Hypothetical question about AES output
Consider that you stumble upon 5 different AES output strings. One of these strings can be decrypted with a secret phrase, the other four strings are based on the real string but have had random parts ...
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Practical consequences of using functional encryption for software obfuscation
I came across this article, which describes a method, developed by UCLA CS professor Amit Sahai et al, for using functional encryption in order to achieve software obfuscation. The paper that the ...
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A situation where security by obscurity might be the best solution - or am I wrong?
Imagine the following situation. There is an application for a microcontroller-driven system. The profits are made from manufacturing and selling the device itself. However, it is expected, that the ...
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