It is worth noting that these hash functions do have a limit to the input size of their data. So that input length itself has an upper bound. From FIPS 180-4: SHA-1, SHA-224, SHA-256: Input length is bounded to $2^{64}$ bits. SHA-384, SHA-512, SHA-512/224, SHA-512/256: Input length is bounded to $2^{128}$ bits.

2015年7月21日 · I'm using crypto lib to creating SHA1 hash: crypto.createHash('sha1').update(hashValue).digest('hex') The typical result is a9993e364706816aba3e25717850c26c9cd0d89d.

I think the OP's confusion comes from a string representing a SHA1 hash takes 40 bytes (at least if you are using ASCII), which equals 320 bits (not 640 bits). The reason is that the hash is in binary and the hex string is just an encoding of that.

We denote by B the byte-length of such blocks (B=64 for all the above mentioned examples of hash functions), and by L the byte-length of hash outputs (L=16 for MD5, L=20 for SHA-1). The authentication key K can be of any length up to B ... the minimal recommended length for K is L bytes (as the hash output length).

For a given input message m, it first appends some bits (at least 65, at most 576) so that the total length is a multiple of 512. Let's call p the added bits (that's the padding). The padding bits depend only on the length of m (these bits include an encoding of that length, but they do not depend on the value of the actual bits).

2009年3月5日 · I would use VARCHAR for variable length data, but not with fixed length data. Because a SHA-1 value is always 160 bit long, the VARCHAR would just waste an additional byte for the length of the fixed-length field. And I also wouldn’t store the value the SHA1 is returning. Because it uses just 4 bit per character and thus would need 160/4 = 40 ...

2011年8月1日 · Breaking SHA1 using a length extension attack. 0. Length of plain text from it's SHA1. 92.

For example for hash hex string of length 8 the probability of having a collision reaches 1 % when the repository has just about 9300 items (git commits). For 110 000 commits the probability is 75 %. But if you have hash hex string of length 12 the probability of …

2018年3月2日 · A sha256 is 256 bits long -- as its name indicates. Since sha256 returns a hexadecimal representation, 4 bits are enough to encode each character (instead of 8, like for ASCII), so 256 bits would represent 64 hex characters, therefore you need a varchar(64), or even a char(64), as the length is always the same, not varying at all.

2019年11月14日 · Currently iIam configuring SHA1 hash function which takes default length as 128 bit. Is it OK to configure with this, since I see in most of the SHA1 uses 160 bit? So what is the most common length used for SHA1 Hash? Assuming that you mean output size: the output size of SHA-1 is 160 bits (20 bytes) and cannot be configured. In some cases ...