Cryptography Stack Exchange
Cryptography Stack Exchange

Questions tagged [shs]

This tag is for posts that specifically refer to the Secure Hash Standard (SHS), which is published by the NIST (FIPS PUB 180 to FIPS PUB 180.4).

The Secure Hash Standard (SHS) is approved by the Secretary of Commerce of the United States, and it currently specifies the secure hash algorithms - SHA-1, SHA-224, SHA-256, SHA-384, SHA-512, SHA-512/224 and SHA-512/256 - for computing a condensed representation of electronic data (messages).

The SHS applies to all U.S. federal agencies and departments for most unclassified information. Entities outside of the U.S. government may adopt this standard.

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How were the arbitrary values used inside SHA-256 determined?

As I study SHA-256, I wonder how the values inside the algorithm were determined. Take a look, for example, at how the 16-64th Words are generated. (in Java language) for (int j = 16; j < 64; ++j) { int s0 = Integer.rotateRight(words[j -…
Synchronic
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What technical flaw in the Secure Hash Standard was the NIST referring to?

On July 11, 1994, the NIST proposed an interesting revision to FIPS 180, about the Secure Hash Standard: A revision of Federal Information Processing Standard (FIPS) 180, Secure Hash Standard (SHS), is being proposed. This proposed…
Patriot
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Rationale of the SHA-256 sigma function definitions

When the sigma functions are defined in equations (4.4) and (4.5) in FIPS PUB 180-4, the defined functions show the traditional sigma summation symbol, with limits 0 to {256} and 1 to {256}. The definitions, however, are in terms of circular right…
user258279
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How are messages larger than 512 bits padded in SHA-256?

In the NIST documentation for the Secure Hash Standard, it says to pad every message by appending the bit "1" to the end of the message, followed by k zero bits, where k is equal to the equation l (length of message in bits) + 1 + k = 448 mod 512.…
user41777