23 questions linked to/from Definition of textbook RSA
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### Which attacks are possible against raw/textbook RSA?

The PKCS#1 standard defines multiple padding schemes for signature generation/verification (EMSA-PSS and EMSA-PKCS1-v1_5), and encryption/decryption (EME-OAEP and the less safe EME-PKCS1-v1_5). ...
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### RSA PCKS1 v2.1 RSAES-OAEP algorithm

Using RSA public key (n,e) the encryption of a message is c= (m^e) mod n and the corresponding message is decrypted as ...
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### Input limitations on the RC6 cipher

RSA has limitation in input size for encryption and decryption. Can RC6 be used for encryption and decryption of files larger than 5 MB? Is there any limitation for input size? Is RC6 safe for using ...
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### RSA encryption/decryption process is not working correctly

I'm trying to apply the RSA cryptosystem to encrypt a byte M=72, using predefined modulus n, public key exponent ...
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### RSA How to select a value K such that $e d = 1 + k \varphi(N)$ holds

I am learning RSA cryptography. The part I am stuck on is understanding how k and the public exponent $e$ is selected. Given the formulas; Decrypting: $c^d \bmod N = (m^e)^d \bmod N$ Which is equal ...
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### Why is padding used for RSA encryption given that it is not a block cipher?

In AES we use some padded bytes at end of message to fit 128/256 byte blocks. But as RSA is not a block cipher why is padding used? Can the message size be any byte length (is the encrypting agent ...
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### Help with RSA step

There's one thing in RSA that haunts me. In books there's just a statement, that $$ed \equiv 1 \bmod \varphi(n)$$ is taken from Euler's function somehow. And than we use it to get m^{ed} \equiv ...
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### Is it safer to encrypt twice with RSA?

I wonder if it's safer to encrypt a plain text with RSA twice than it is to encrypt it just once. It should make a big difference if you assume that the two private keys are different, and that the ...
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### When to use RSA and when ElGamal asymmetric encryption

If i am not wrong in cryptography there are 2 basic cryptographic schemes for public key cryptography. RSA encryption whose security is based on the infeasibility of solving the factoring of big ...
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### Why plain RSA encryption does not achieve CPA-security?

Why plain RSA encryption does not achieve CPA-security?
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### I think I'm trying to find the C in an RSA cipher to find the key for an aes_128_ecb cipher, can anyone tell me if I'm on the right track?

And if I am on the right track, how do I reach the solution from here? I'm doing a CS game and I've hit a wall (I'm a rank beginner when it comes to encryption) on the encryption portion. I've been ...
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### Does order matter for RSA when used multiple times?

I actually have no idea how RSA works, but I currently (think that I) know Public and private keys are mathematically doing their opposites Therefore, the order in which they are applied doesn't ...
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### How does the math part of RSA work? [duplicate]

I understand the theoretical part of RSA (the concept of public and private keys), but I don't understand the mathematical part. Can anyone please explain it to me in simple terms? Thanks.