bcrypt is an intentionally slow hash algorithm specially designed for passwords.
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Is this algorithm secure?
I recently found this site, proposing a hashing algorithm for passwords.
They describe the following:
pad the password on both sides with SHA1(email) to ...
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2answers
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Many consecutive hashes to slow down brute force attack?
I've heard that hash algorithms like bcrypt are more secure because they take longer to complete, and therefore take much longer to prute force, without a noticable ...
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Knowing a valid salted hash for an unknown secret, is it possible to compute another valid hash?
$H(s,r)=d$ is a function that hashes the secret string $s$ with a salt $r$, and returns a digest $d$.
$r$ may be arbitrarily chosen and each $r$ returns a different $d$.
For any $d$, $r$ is known from ...
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BCrypt vs Key Stretching MD5
Ars technica posted an article about the latest in cyber warfare from the stuxnet crew.
They key stretched MD5 by iterating it 10,000 times. It seems to be effective at handicapping HashCat's gpu ...
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Why is Bcrypt called a Key Derivation Function?
I am trying to understand why is bcrypt called a Key Derivation Function?
I looked up the details of Ekfblowfish on Usenix article here:
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1answer
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Hashing a password with SHA256 on the client then bcrypt on the server
I'm trying to implement a cryptographically secured storage site (not Mega, or anything similar) and am trying to prevent the user's password from ever touching the server. The password is used to ...
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1answer
184 views
Blowfish Encryptions in Bcrypt hashing algorithm
I am trying to understand the ExpandKey function used in the bcrypt hashing algorithm. As per the documentation of bcrypt hashing algorithm on USENIX here:
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1answer
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which of these is more secure (bcrypt vs srp)
OK, here's the two different ways I was thinking about making the authentication for the login thing to store the passwords securely.
The first is the following.
Client hashes password ...
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1answer
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Can iterated key expansion in Blowfish slow down bruteforce attacks on small key sizes?
Suppose I have to use 64-bit keys for encryption (e.g. to comply with export restrictions). For this question, assume this key is truly random, and the encryption algorithm is Blowfish.
Blowfish key ...
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1answer
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Storage of Private Keys
I'm building a bitcoin web application that will require all users to be assigned a wallet for adding funds to their account. I plan on exposing the public key to the user (the bitcoin address). Users ...
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Do I have to recompute all hashes if I change the work factor in bcrypt?
The well-known article about why we should use bcrypt for hashing passwords mentions the work factor - some parameter to the algorithm that determines how long one hashing should be in terms of number ...
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Adaptive Hash Functions: How to tell how many iterations were used?
If an adaptive hash function like bcrypt or PBKDF2 is used in hashing passwords, the number of iterations used in the hashing process can be configured.
For a penetration tester or a malicious ...
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Is bcrypt better than GnupPG's iterated+salted hashing method?
GnuPG has slow hash built-in in form of iterated+salted S2K.
Does it have disadvantages in comparance with bcrypt or scrypt? Is GnuPG's slow hash method easily automated in GPUs?
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bcrypt - collision-resistance against chosen salt and work factor?
Would it be difficult to find $\:$ cost,salt,input,password0,password1 $\:$ such that
bcrypt(cost,salt,password0,input) = bcrypt(workfactor,salt,password1,input)
and $\:$ password0 != password1 $\:$ ...
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1answer
174 views
Does ShaCrypt have the properties which make BCrypt slow on GPUs?
Sha256Crypt / Sha512Crypt are designed based on ideas of BCrypt but use SHA instead of Blowfish because of political requirements.
The Sha*Crypt algorithms have the advantage that they are used in ...
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1answer
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How is BCrypt secure when it uses a static dataset for blowfish hashing?
I'm planning on using this Javascript BCrypt implementation, but as you can see in the code, it uses a 4KB precalculated dataset for the P and ...
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Why can't one implement bcrypt in Cuda?
I had heard that although it's easy to implement message digest functions like MD5, SHA-1, SHA-256 etc. in CUDA (or any other GPU platform), it is impossible to implement bcrypt there.
bcrypt is ...
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1answer
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Can one efficiently iterate valid bcrypt hash output values?
bcrypt is an intentionally slow hash algorithm. In my last protocol idea, I wanted to use it to expand a password and then only transfer the bcrypt-hashed password.
An efficient attack on this would ...
