Cryptography Stack Exchange
Cryptography Stack Exchange

Questions tagged [ripemd]

The RACE Integrity Primitives Evaluation Message Digest (RIPEMD) is a family of cryptographic hash functions.

The RACE Integrity Primitives Evaluation Message Digest (RIPEMD) is a family of cryptographic hash functions, first published in 1996. RIPEMD was based upon the design principles used in MD4, and is similar in performance to the more popular SHA-1. RIPEMD-160 is an improved, 160-bit version of the original RIPEMD, and the most common version in the family. In August 2004, a collision was reported for the original RIPEMD. Yet, this does not apply to RIPEMD-160.

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RIPEMD versus SHA-x, what are the main pros and cons?

RIPEMD is a family of cryptographic hash functions, meaning it competes for roughly the same uses as MD5, SHA-1 & SHA-256 do. The Wikipedia page for RIPEMD seems to have some nice things to say about it: "designed in the open academic…
user950
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Why hashing twice?

I'm trying to understand the Bitcoin protocol, and sometimes see instructions like this: The TransactionId is defined by SHA256(SHA256(txbytes)) or The hash of the public key is generated by performing a SHA256 hash on the public key, and then…
Timur Lemeshko
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How to provide secure "vanity" bitcoin address service?

Bitcoin addresses are RIPEMD-160 hashes of the public portion of a public/private ECDSA keypair (along with an abbreviated hash of the hash to provide a check code, as @pulpspy notes in a comment). They are generally base-58-encoded. See Address -…
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How to deal with collisions in Bitcoin addresses?

When creating a Bitcoin account, you need to issue a couple of private/public ECDSA keys. Then, you derive your account address by taking a 160-bit hash (through SHA-256 and RIPEMD) of the public key and use a custom Base 58 algorithm to convert it…
perror
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How does RIPEMD160 pad the message?

For RIPEMD hashing algorithm on hardware I am not exactly getting how padding works So as per my understanding padding will work like explained below: For ripemd 160 message should be multiple of 512 bits. So, along with message to make it 512 bits,…
seeker
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Does knowing multiple hash of the same content make it more likely to generate original plain text?

Say I'm trying to brute force the original plain text of an SHA256 hash, does knowing the RIPEMD160 hash of the same text help? In other words, does providing access to hash values of the same text generated by multiple algorithms decrease security?
Josh
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How to pronounce RIPEMD-160?

Do I pronounce it as a word or letter-by-letter, i.e., "R-I-P-E-M-D"?
Aditya
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SHA256 and RIPEMD160 collisions

H = ripemd160(sha256(ECMultiply(A,G))) A - 32-byte number, H - 20-byte number, G - generator point, ECMultiply - elliptic curve point multiplication. Is it true that there is many A that have the same H?
Denis Leonov
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Why is a 1 added after the message input and before adding padding zeros (if necessary) when using SHA256 or RIPEMD160?

In preparing an input for SHA256 or RIPEMD-160 a single bit (1) is appended to the message before adding any necessary zero padding and before adding the bitlength (64 bits) to form 1 or more 512 bit blocks. What is the purpose of adding the single…
JohnGalt
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Long Term Security of Truecrypt's hash function?

Does Truecrypt's hash function weaken the security of a chosen cipher cascade? Considering I want to choose a cipher cascade of 3 ciphers for long term security (50+ years) for my archived data on blu-ray disk. Truecrypt allows me to choose only 1…
user3200534
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Computing the powers of hash (ripemd-160) function

Is there a way I can compute $2^{100}$th power of ripemd-160 of my string, just like I can do with square matrix powers? I.e. can I easily compute ripemd-160 large amount of times?
A. Can
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Sane implementations of Bitcoin cryptography routines w.r.t. side-channel attacks

Bitcoin uses SHA-256, Base58Check, ECDSA (Sep256k1) and RIPEMD-160 as the basis of its encryption (see this article for a short guide on how addresses are created). I would like to create an iOS-based wallet app that offers reasonable…
Etan
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RIPEMD160 - how were these constants created?

I have been through several sources and papers, but I can't seem to find how these rotation constants were created. Are these constants arbitrary, or were there chosen by some kind of permutation? I can't really find any source. The order of the…
Alexander Weps
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Can you identify these cryptographic algorithmic symbols?

I am mostly self taught and have limited knowledge of the symbology in the image below. It is a diagram of a sub block the RIPEMD-160 algorithm: Are such symbols standardized? Is there a good dictionary or atlas someone is aware of that could link…
sh34v3
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CSPRNG for Contract Bridge (RAND_MAX = 0xAD55E315634DDA658BF49200)

Some background information: In contract bridge, there are 0xAD55E315634DDA658BF49200 (just under 2^96) possible bridge deals. Since the 1990s, bridge deals for major tournaments were generated on PCs and dealt using dealing machines. Initially, the…
woefulwabbit
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