Q&A mechanism based on SHA256 - fast computing problem
$30-250 USD
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$30-250 USD
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There is a question and answer mechanism. It consists in the fact that the question "Q" is 4 bytes, for eg. 0xAA 0xBB 0xCC 0xDD. The answer "A" is generated in such a way that the sequence "S" with a length of 8 bytes is added to the question "Q". A sequence of 12 bytes is then created. The SHA256 hash function of that 12 byte string is then computed. The first 4 bytes of the calculated SHA256 value are the response "A". So, for example:
Q = 0xAA, 0xBB, 0xCC, 0xDD
S = 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08
SHA246 (AABBCCDD0102030405060708) = e455df10f57a47498c12c5eaad9b93f525aba1252a7a3a7fee160878db0b6aa8
so: A = e455df10 (first 4 bytes).
I know 3 pairs of sample Q questions and A answers. The goal is to calculate S which is a sequence of 8 bytes. I wrote a program that adds 8 bytes S to the Q that I know. Then it calculates SHA256 and checks if the first 4 bytes agree with the answer A I know. It is a brute force attack. The problem is that the loop substitution 8 bytes and the SHA256 calculation for the combination 0xFFFFFFFFFFFFFFFF is very time consuming (even computing on GPU takes tens of days if not more). Is it possible to find the sequence S in a different way and within a reasonable time - a few hours or days maybe?
If someone could help me on a faster method to solve this problem, I would be very grateful.
We will do your C work
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Hi,
I have great experience in the design and implementation of SHA-256 hash function from scratch in C/C++. I understood the problem that you are presently dealing with. The main problem here is the fact that cryptographic functions like SHA-256 are one way functions, and it's computationally intensive to find a collision in the inputs. I am very much eager to discuss more on this topic with you. Please feel free to contact me via chat, so that we can discuss further and start working on this amazing project as soon as possible!
Best Regards,
Aravind A
Hello
Hope you are doing well
I am a C/C++ developer with 5 years' experience.
I am so interested in your project.
I will be happy hearing from you.
Thanks
Hello
I've gone through your posted job description for Q&A mechanism based on SHA256 - fast computing problem
I have successfully 300+ project and have 10+ years hands experience with Cryptography, CUDA, C++ Programming and C Programming
Please share some details about your project so will start ASAP.
I am always ready for a technical test/interview anytime soon.
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Looking forward working with you.
Let's have a quick conversation on the details to proceed further with this project.
Thank You,
Dilip
Hello, how are you? how is it going well there now?
I've checked your project description with carefully.
I have already worked on this type project and delivered successfully.
I am ready to discuss with you about further more details.
Thanks regards.