A 256-bit variant of Secure Hash Algorithm 2
SHA-256 is a 256-bit variant of the SHA-2 algorithm, that is used heavily in Bitcoin.
Questions tagged [sha256]
160 questions
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votes
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Theoretical minimum # of logic operations to perform double iterated SHA256?
What is the theoretical minimum number of logical operations an ASIC needs to perform to compute double iterated SHA256, i.e., sha(sha(•))?
Geremia
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Get a correct SHA256 of a PublicKey as bytes
I’m new in code develop and I’m studying it by myself (books, tutorials, official help of sites…) since a year VB.NET. A lot of information I read is in C# that I rewrite in VB.NET.
I’ve started four months ago to read and write some code about…
B221D9
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What is the fastest public SHA256^2 code for x86?
I am asking about the double SHA256 hashing function - the one that bitcoin uses.
Which publicly available implementation is the fastest one out there?
It can be in assembler, as long as it is for x86, also 64 bit.
Gigi
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sha256 implementation
Hi I'm trying to use bitcoind's vectorized SHA256 implementation in src/crytpo/sha256_*.cpp in my project. On a first try feeding a block of 64 null bytes to SHA256D64 I obtain the hash {0xe2, 0xf6, 0x1c, 0x3f, 0x71, 0xd1, 0xde, 0xfd, 0x3f, 0xa9,…
potuz
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Can you crack SHA-256?
From my understanding, a hash function is an algorithm that takes a unique input and produces a unique output, and a secure hash like SHA-256 cannot be reverse engineered. I saw this thread Won't ASIC miners eventually break SHA-256 encryption?…
James Palmer
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Where is the string that generates the hash with 18-20 zeroes?
When bitcoin miners mine, they have to solve a difficult and extremely repetitive math problem using the SHA256 algorithm. The miners are trying (basically playing lottery and almost always working in large groups) to get a hash with (currently) at…
Number File
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Merkle Root for Block 100000: calculation in Excel
I am stuck doing the calculations for the infamous block 100000. I am doing those in excel. I am trying to add as much detail here of the operation I am doing and intermediate results.
TX1:…
Zippo76
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btc mining, the largest supercomuter in existence?
I'm not sure of the best place to ask this so I'll ask it here. I had read that as far as computing power, the Bitcoin nodes represent the largest distributed super computer in the world in finding the SHA-256 hashes. Now it seemed to me such a…
marshal craft
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calc Block Header hash
I use the following code to calculate the header hash.
function serializeBlockHeader(blockHeader) {
const version = Buffer.alloc(4);
version.writeUInt32LE(blockHeader.version);
console.log('version length', version.length, version)
…
eason
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How long would it take for all smartphones on the planet to fully reverse a SHA-256 hash?
I am aware that, theoretically speaking, there is no way to guarantee that a reversed hash is actually what is inputted to the hashing function. However, let's say that I have an image, I write down the file size of that image and then run it…
Darcy Sutton
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BitCoin SHA256 - ShortCut
just a general question, would it be ethical to start mining bitcoin using a shortcut, in the SHA256 hash (if that may even be possible), and mining at a much much faster speed using very less processing power/electricity than everyone else?
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Why is the SHA256 regularly applied twice?
I have come across at least two times in bitcoin computations that the sha256 algorithm is applied twice - merkle root computation and address computation. Why is this?
Not sure of an appropriate tag - please edit.
Prince M
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