# welcome to the sha1 hash,sha256 hash,sha512 hash generator

this is my sha1 hash,sha256 hash,sha512 hash generator

This sha hash generator support 5000 characters , if the text is more than 5000 characters, the text will be trim to 5000 characters.

the sha hash generator can generate sha1, sha2-224 ,sha2-256, sha2-384 ,sha2-512 hash for you.

Please select the hash algorithm and type the string you want to encode below

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sha1 hash generator

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what is a sha hash?

## sha1 encrypt

The whole name of sha is Secure Hash algorithms . the Secure Hash Algorithms are a serials of cryptographic hash functions which is invented by National Institute of Standards and Technology. The National Institute of Standards and Technology is a measurement standards lab , which is also a non-regulatory agency under the United States Department of Commerce. The National Institute of Standards and Technology in the history offered many product to promote innovation and industrial competitiveness of US.

As the time of writing , there are 4 generations in the sha hash family , they are the sha-0 (sha0) hash, sha-1(sha1 hash) hash, sha-2(sha2 hash include sha256 hash and sha512 hash)hash ,and sha-3(sha3 hash) hash. we will talk about each of the hash algorithm In detail.

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The sha-0 hash (sha0 hash) and sha-1 hash (sha1 hash)

## sha1 encryption algorithm

The sha1 hash is a cryptographic hash function algorithm that is invented by NSA of US(national security Agency of united states) and published to the public by the US National Institute of Standards and Technology as a Federal Information Processing Standard.

A forward warning :As the time of writing the sha1 hash is no longer consider secure ,and it is recommended to use sha-2 or sha-3 as sha-1’s replacement.

The original sha1 hash is designed as a part of Capstone project , which is a US government long term to develop cryptography standards for public and government use.

The sha1 algorithm is designed to produce a message digest by using the similar principles as the MD4 and MD5 message digest algorithms.in fact both sha and md5 are came from MD4. But the sha hash algorithm’s design is more conservative.

The original form of sha hash algorithm was published in 1993 by the title Secure Hash Standard, by National Institute of Standards and Technology. But as the time of publication they found a flaw in the sha algorithm, so they withdraw the original edition , the short lived original edition of sha has algorithm is called the sha-0 ,or sha0 hash algorithm. The revised edition of algorithm is published in 1995 , and it well known as the sha1 hash algorithm.

The difference between the sha-0 and sha1 hash is only a single bitwise rotation in the message schedule of its compression function. NSA said this correction can increase the cryptographic security of the original sha-0 hash algorithm.So the first applicable is sha1 hash algorithm rather than sha-0.

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The real world applications of sha1 hash

## sha1 hash checker

The sha1 hash is used in many modern security protocols and applications, such as TLS,SSH, IPsec ,PGP and etc, beside security applications and protocols sha1 hash is also used to generate unique identifier in many user applications to identify revisions, or used as a checksum for data integrity.

The famous linux creater . Linus Torvalds once said about git , a Revision control systems for controlling program versions :

“If you have disk corruption, if you have DRAM corruption, if you have any kind of problems at all, Git will notice them. It’s not a question of if, it’s a guarantee. You can have people who try to be malicious. They won’t succeed. […] Nobody has been able to break SHA1 hash, but the point is the SHA1 hash, as far as Git is concerned, isn’t even a security feature. It’s purely a consistency check. The security parts are elsewhere, so a lot of people assume that since Git uses SHA1 hash and SHA1 hash is used for cryptographically secure stuff, they think that, Okay, it’s a huge security feature. It has nothing at all to do with security, it’s just the best hash you can get”

Japanese game console manufacture Nintendo also use sha-1 hash for booting signature verification, although the verification is bypassed by hacker later .

In united states ,it is required by law that certain US government applications must use the sha hash algorithm inside them, such as cryptographic protocols and algorithms to prevent information leaks. many enterprises also use the sha1 hash algorithm in their application, products or daily work.

The sha1 hash algorithm is being retired in US governments uses, just as a quote form National Institute of Standards and Technology : “”Federal agencies should stop using SHA1 hash algorithm for…applications that require collision resistance as soon as practical, and must use the SHA-2(sha256 hash and sha512 hash) family of hash functions for these applications after 2010″.

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The attacks against sha1 hash algoritm

## sha256 checksum

Why the sha1 algorithm is being retired ? that’s because people find ways to successfully attacked the algorithm.

let us say that, L is the number of bits in the message digest of sha1 hash ,to find a message that corresponds to a given message digest, one can use a brute force search in approximately 2L evaluations. This kind of brute search is called a preimage attack and may or may not be practical depending on L and the actual computing environment.

There is another kind of attack that is called a collision attack,The collision attack consisting of finding two different stream of data that produce the same message digest ,the collision acctack requires on average only about 1.2 × 2L/2evaluations using a birthday attack.So the strength of a particular hash function is usually compared to a symmetric cipher of half the message digest length. In the SHA1 algorithm, with a 160-bit message digest, was originally thought to have 80-bit strength.

But in reality Cryptographers have produced collision pairs for SHA-0 and have found algorithms that should produce SHA-1 collisions in far fewer than the originally expected 280 evaluations.

For example. In early 2005, Rijmen and Oswald published a paper , in the paper , they find a kind of attack on a reduced version of SHA-1 with 53 out of 80 rounds of computation , which is much fewer than the original 280 operations.

In February 2005, an attack was published by Xiaoyun Wang, Yiqun Lisa Yin, and Hongbo Yu , which only need fewer than 269 operations for a successful attack on the full version of SHA1 hash algorithm. There are several similar attacks on sha-1 during the following years. Made the sha-1 much venerable than ever. And the original sha-0 hash is a even weaker target, in 2008 people can use an attack called the boomerang attack brought the complexity of finding collisions down to 233.6, which is estimated to take 1 hour on an average PC in 2008.

So the sha1 hash algorithm is being placed under the bed now, let us what its successor look like .

## The SHA-2 hash(include sha256 hash and hash 512 hash)

## sha1 to text

The sha-2 hash algorithm(include sha256 hash and hash 512 hash) is designed by NSA in 2001. The sha-2 algorithm works the same as sha-1 which use a serials of digital bits and produce a fixed length of hashed value. People can use the sha-2 algorithm as a checksum for digitial data.

There a 6 hash functions in the sha-2 hash family, they are sha224 hash, sha 256 hash ,sha384 hash , sha512 hash, sha512/224 and sha-512/256. These hash algorithm can produce 224,256,384 and 512 bits length of sha-2 hash. The sha256 hash algorithm and SHA512 hash algorithm are novel hash functions computed with 32-bit and 64-bit words, respectively. The SHA224 hash algorithm and SHA384 hash algorithm are simply truncated versions of sha256 hash and sha512 hash , just computed with different initial values. The SHA-512/224 and SHA-512/256 algorithm are also truncated versions of SHA512 hash, but the initial values are generated using the method described in Federal Information Processing Standards (FIPS) PUB 180-4.

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The application of sha-2 hash algorithm(sha256 hash ,sha512 hash)

Just like sha-1 ,sha-2 hash function is also heavily used in security applications and protocols ,such as SSL,TLS, PGP , IPsec, SSH and S/MIME.

Beside security applications and protocol ,sha-2 is also used in many user applications, such as :

- Debian, a popular linux distribution use sha256 to authenticate debian software packages,
- The DomainKeys Identified Mail (dkim), a very popular email massage signing method also use sha256 hash.
- DNSSEC and password hashing function of linux are also going to use sha-2 to replace sha1 hash algorithm.
- Us government also demand to replace sha-1 with sha-2 in any government agency applications.

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The attacks on sha2 hash(sha256 hash and sha512 hash)

Although SHA2 hash(sha256 hash and sha512 hash) has some similarity to the SHA1 hash algorithm, there is not a partially useful attacks on sha-2. As the time of writing, the best public attacks break preimage resistance for 52 rounds on SHA256 hash or 57 rounds on SHA512 hash, and collision resistance for 46 rounds of SHA256 hash, Only the collision attacks are of practical complexity; none of the attacks extend to the full round hash function.People now find that SHA256 hash and SHA512 hash algorithm , and to a lesser degree, the SHA-224 and SHA-384 are prone to length extension attacks, make it insecure for ceratin applications.

It is now recommended to switch to SHA-3 for 512 bit hashes and to use SHA-512/224 and SHA-512/256 instead of SHA-224 and SHA256 hash algorithm. This also happens to be faster than SHA-224 and SHA256 hash algorithm on x86-64, since SHA512 hash algorithm works on 64 bit instead of 32 bit words.

Only the collision attacks are of practical complexity; none of the attacks extend to the full round hash function.

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The SHA-3 hash

The sha-3 hash algorithm is the newest member in the sha family.The sha-3 is publish in 2015.8 by NIST.The internal structure is quite different from the SHA-1 and SHA2 hash (sha256 hash and sha512 hash)algorithm.

The sha-3 algorithm is designated to be the successor of sha-2 ,although NIST do not want to retire SHA2 hash now. The purpose of SHA-3 is that it can be directly substituted for SHA-2 in current applications if necessary.

The sha-3 algorithm is the chose winner from the NIST hash function competition which is held in 2006 by NIST started to organize the to create a new hash standard.

you can find the Wikipedia page of sha1 hash algorithm at Wikipedia sha1 hash algorithm page

if you are a python programmer you can find the sha1 lib function at python2.7 sha1 lib function page

if you want to use sha1 function in your php code you can find it here php sha1 function