Scrypt is a recent key derivation function designed for password storage. It aims to improve on earlier similar functions such as PBKDF2 and bcrypt by requiring significant amounts of memory in addition to computation time.

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Are there more modern password hashing methods than bcrypt and scrypt?

This question made me start thinking about password hashing again. I currently use bcrypt (specifically py-bcrypt). I've heard a lot about PBKDF2, and scrypt. What I'm wondering is if there are any "...
7
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1answer
119 views

What are the recommended scrypt cost factors for 2016?

I've been trying to look for the answer, but the latest one I found was outdated by three years. So what are the recommended scrypt cost factors for 2016?
2
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3answers
302 views

How does ASIC cryptocoin miners affect the security of scrypt?

Is the availability of these miners a reason to favor bcrypt (or something else) over scrypt? I mean, the goal of a password hash function is to maximize the work needed for an attacker to break a ...
0
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2answers
45 views

Isn't using pbkdf2 + scrypt + bcrypt best?

Since slower is better and key stretching is an awesome way to increase security over potentially low entropy passwords, doesn't it make sense to use all three? To be clear, this is about ...
46
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9answers
5k views

Why improvising your own Hash function out of existing hash functions is so bad

I'm afraid I'll have tomatoes thrown at me for asking this old question, but here goes. After reading that cooking up your own password hash out of existing hashing functions is dangerous over and ...
2
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3answers
54 views

Pre-generating 'secure tokens'

In our web app we make good use of single use tokens. For example, when somebody creates any of the three "accounts", resets their password, or any other number of things that require random single-...
0
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0answers
47 views

Data Model for a Tokenizing Data Storage System

Hashing Strategy for a Tokenizing Data Storage System We are designing the data model (storage at rest, in a database) for a PCI compliant data storage system using Amazon Web Services (AWS) and ...
3
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1answer
45 views

Sending noise over wire, using hashes of noise to carry data

Imagine highly dystopian environment, where oppressive evil government MITMs over all connections and uses DPI to thwart any attempts to use TLS/SSL, TOR, I2P etc. To establish connection, these ...
4
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2answers
136 views

Password manager's hash choices (scrypt + sha256)

Background information: Master password is a stateless password manager. It (deterministically) generates a password using a hash function, depending on your master password and the site name (also ...
8
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4answers
430 views

Major industry password leaks using salted HMAC but without eg PBKDF2, scrypt

I'm trying to convince higher-ups on a project to use an iterative strengthening function to secure password-storage for a new system. The current proposal would store something like an HMAC of a ...
4
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1answer
91 views

Is the 'demo' scrypt a good choice for file encryption?

The scrypt command line utility (see http://www.tarsnap.com/scrypt.html) is actually just a demonstration of the script password hashing algorithm. However, for simple command line encryption of ...
5
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2answers
673 views

Scrypt + Bcrypt = cascade hashing [duplicate]

I've read here that hashing with differents algorithms would be a good idea. Can you confirm that? In your experience, is it useful and safe? Does it entail any security holes?
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2answers
634 views

Why does node.js scrypt function use HMAC this way?

According to the documentation, the scrypt hash function works like so: The hash function does the following: Adds random salt. Creates a HMAC to protect against active attack. Uses ...
1
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2answers
128 views

Double hashing using a relatively new hash and a old, tested one

Note: I am relatively new to cryptography in general, so please point out if I make any misconception here. I heard that you should always use well known crypto/hash functions, that have already been ...
3
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1answer
156 views

How to implement application-specific passwords using strong hashes?

I am implementing a service where application-specific passwords seem a good choice to improve security. A question on why and when they might make sense has already been discussed here Google ...
3
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1answer
341 views

How secure is Scrypt, really?

I've been recently taking a hard look at the scrypt system for storing users' passwords. However, I'm rather worried about it's security because of things like Litecoin miners. Is scrypt secure ...
9
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1answer
408 views

Any problems with scrypt yet?

In the question Do any security experts recommend bcrypt for password storage? Thomas Pornin recommends the hashing function scrypt but saying it is "too new to be recommended on a general basis". ...
3
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1answer
83 views

Basic scrypt question

Suppose we throw a regular password into scrypt to generate some data. Scrypt allows us to specify how large the output data should be. My question is, to take an extreme case, if we ask for a 1 GB ...
1
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1answer
118 views

Designing a password auth/reg system

I'm designing a user reg/auth system for a website and came up with this design for password based authentication. I'd like to know if this is reasonable. (ignoring cookies for caching credentials, ...
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3answers
7k views

Is a HMAC-ed password is more secure than a bcrypt-ed or scrypt-ed password?

Given an option , which one should I choose , a HMAC for storing a password securely or a bcrypt or scrypt library?
2
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2answers
216 views

Combining SCRYPT + a short crc

I'm considering using SCRYPT for password storage. (I'm open to PBKDF2 as well, or bcrypt by itself). The issue is that I don't want this to become a potential point for a DDOS attack, given the ...
2
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2answers
102 views

Simple PBKDF2 vs. scrypt question

scrypt was designed to use more memory. We can use its parameters to specify (approximately) how much memory we want it to require. But both scrypt and PBKDF2 allow us to specify the output data size....
0
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1answer
101 views

How are SCrypt's memory-hard requirements substituted with more CPU?

I've implemented scrypt with two separate APIs and in both there existed no settings providing a way to substitute CPU for memory. Both were locked one-to-one with rounds and memory. However in ...
2
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0answers
555 views

Database row level encryption scheme

I am wanting to secure some highly sensitive data in a database. This would mean that the data needs to be encrypted and remain secure for 100 years if it were to fall into adversary hands. I also ...
3
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1answer
325 views

Has scrypt been broken, finally?

If I understand correctly, according to this: http://blog.ircmaxell.com/2014/03/why-i-dont-recommend-scrypt.html, looks like the attacker can just create an optimimized version of scrypt that produce ...
1
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1answer
183 views

I know scrypt is newer than bcrypt, but is there any reason it would be weaker?

From what I read, scrypt is (on paper) more secure than bcrypt, but it's pretty new so it's better to let it get time-tested and scrutinized first. However, is there any good, compelling reason to ...
0
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4answers
3k views

Is salted MD5 or salted SHA considered secure?

Is using something like bcrypt or scrypt necessary? The hashes are so much longer to store in a database. Can one get away with using salted MD5 or SHA and still be secure?
0
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0answers
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Length-constant password comparison in scrypt? [duplicate]

E.g.: XORing the candidate against stored then comparing against 0. Do I need to worry? (my question is much in the same style as this question: Does bcrypt compare the hashes in "length-...
13
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1answer
574 views

Is the Litecoin Scrypt hashing technique a threat to hashed passwords?

The Bitcoin alternative, Litecoin uses a different algorithm to protect the block chain, namely Scrypt (not Sha256). Given that GPU accelerators exists, and ASICS are due to be released, does the ...
2
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1answer
326 views

ASIC/FPGA hardwares to compute Scrypt hashes [closed]

this company claim Scrypt mining by ASIC (on crypto currencies who use scrypt hashing as proof of work) scrypt is made to keep ASIC/FPGA attackers away, is that claim expired?
0
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1answer
374 views

Comparison of bcrypt and scrypt

Is there any comparison of bcrypt versus scrypt? I am particularly interested in how bcrypt(10) bcrypt(20) or even bcrypt(30) scales in comparison to scrypt(1)?
0
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2answers
590 views

scrypt strength with “weak” salt

I'm working on a project where following constrains apply: There's no remote database or any other means of storing extra data like random salt When user logins in, only username and password are ...
10
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3answers
650 views

has scrypt withstood the test of time?

I've always heard that scrypt was better than bcrpyt... because of memory causing GPU a very difficult time to crack. However, the notion always was that scrypt hadn't been tested, it was kind of a ...
5
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1answer
240 views

Password strengthening for PGP

I'm wondering about some of the semantics and security implications of using something like scrypt or bcrypt to "enhance" a password protecting a PGP private key. Essentially, I'm asking about the ...
5
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2answers
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Do SSD's offer significant performance boost for Scrypt?

Being a memory intensive hash, I was wondering if SSD's offer any appreciable performance boost for brute force attacks.
7
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3answers
1k views

How should I choose a difficulty factor for my password hashing function?

Assuming that I'm doing password hashing properly and using bcrypt, scrypt or PBKDF2, how should I go about choosing an appropriate difficulty factor? i.e rounds for bcrypt, iterations for PBKDF2 and ...
25
votes
3answers
18k views

Is bcrypt better than scrypt [duplicate]

Possible Duplicate: Do any security experts recommend bcrypt for password storage? I'm no security expert and do not pretend to be that's why I'm asking here. I write many PHP based ...
3
votes
2answers
935 views

User authentication + database encryption with same password

I'm working on a private project where I need to store a users financial data in a database. I'll encrypt this data using AES, and I'll be using scrypt to generate a AES ecnryption key from a more ...
1
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0answers
223 views

Recomended hash algorithm [duplicate]

Possible Duplicate: How to securely hash passwords? Do any security experts recommend bcrypt for password storage? What would you choose between: PBKDF2 SHA256 (270,000 iterations) bcrypt (...
4
votes
5answers
691 views

What about combining pkdf2 with scrypt? [duplicate]

Possible Duplicate: Would it make sense to use Bcrypt and PBKDF2 together? How does the following password hashing scheme look to you? iterations1 = scrypt iterations required to spend 50ms ...