Split Entire Hash Range Into n Equal Ranges

Posted by noxtion on Stack Overflow See other posts from Stack Overflow or by noxtion
Published on 2010-04-24T20:35:25Z Indexed on 2010/04/24 20:43 UTC
Read the original article Hit count: 167

Filed under:

hashing

|

sha1

|

md5

|

hash

Hello.

I am looking to take a hash range (md5 or sha1) and split it into n equal ranges.

For example, if n=5, the entire hash range would be split by 5 so that there would be a uniform distribution of key ranges. I would like n=1 to be from the beginning of the hash range to 1/5, 2 from 1/2 to 2/5, etc all the way to the end.

I am new to hashing and a little bit unsure of where I could start on solving this for a project. Any help you could give would be great.

© Stack Overflow or respective owner

Related posts about hashing

Is hashing of just "username + password" as safe as salted hashing

as seen on Programmers - Search for 'Programmers'
I want to hash "user + password". EDIT: prehashing "user" would be an improvement, so my question is also for hashing "hash(user) + password". If cross-site same user is a problem then the hashing changed to hashing "hash(serviceName + user) + password" From what I read about salted hash, using… >>> More
Index Hashing vs Normal Hashing

as seen on Stack Overflow - Search for 'Stack Overflow'
What is index hashing ? What are its advantages over regular hashing techniques ? >>> More
Secure hash and salt for PHP passwords

as seen on Stack Overflow - Search for 'Stack Overflow'
It is currently said that MD5 is partially unsafe. Taking this into consideration, I'd like to know which mechanism to use for password protection. Is “double hashing” a password less secure than just hashing it once? Suggests that hashing multiple times may be a good idea. How to implement password… >>> More
SHA512 vs. Blowfish and Bcrypt

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm looking at hashing algorithms, but couldn't find an answer. Bcrypt uses Blowfish Blowfish is better than MD5 Q: but is Blowfish better than SHA512? Thanks.. Update: I want to clarify that I understand the difference between hashing and encryption. What prompted me to ask the question… >>> More
Do encryption algorithms require an internal hashing algorithm?

as seen on Stack Overflow - Search for 'Stack Overflow'
When I use C# to implement the AES symmetric encryption cipher, I noticed: PasswordDeriveBytes derivedPassword = new PasswordDeriveBytes(password, saltBytesArray, hashAlgorithmName, numPasswordIterations); Why do I need to use a hashing algorithm for AES encryption? Aren't they separate? Or is… >>> More

Related posts about sha1

PBKDF2-HMAC-SHA1

as seen on Stack Overflow - Search for 'Stack Overflow'
To generate a valid pairwise master key for a WPA2 network a router uses the PBKDF2-HMAC-SHA1 algorithm. I understand that the sha1 function is performed 4096 times to derive the PMK, however I have two questions about the process. Excuse the pseudo code. 1) How is the input to the first instance… >>> More
Is it possible to get identical SHA1 hash?

as seen on Stack Overflow - Search for 'Stack Overflow'
Given two different strings S1 and S2 (S1 != S2) is it possible that: SHA1(S1) == SHA1(S2) is True? If yes - with what probability? Is there a upper bound on the length of a string, for which probably of getting duplicates is 0? If not - why not? Thanks >>> More
Is it possible to convert a 40-character SHA1 hash to a 20-character SHA1 hash?

as seen on Stack Overflow - Search for 'Stack Overflow'
My problem is a bit hairy, and I may be asking the wrong questions, so please bear with me... I have a legacy MySQL database which stores the user passwords & salts for a membership system. Both of these values have been hashed using the Ruby framework - roughly like this: hashedsalt = … >>> More
Is there any difference between md5 and sha1 in this situation?

as seen on Stack Overflow - Search for 'Stack Overflow'
It is known that 1. if ( md5(a) == md5(b) ) 2. then ( md5(a.z) == md5(b.z) ) 3. but ( md5(z.a) != md5(z.b) ) where the dots concatenate the strings. What happens in the second row if we change all the md5 to sha1? So: 1. if ( sha1(c) == sha1(d) ) 2. then ( sha1(c.z)… >>> More
iPhone: convert string using HMAC-SHA1

as seen on Stack Overflow - Search for 'Stack Overflow'
hi all, i want to generate HMAC-SHA1 of NSString type variable. I see the post but this method give me error in CCHmac(kCCHmacAlgSHA256, cKey, strlen(cKey), cData, strlen(cData), cHMAC); and NSString *hash = [HMAC base64Encoding]; line. Please suggest how can I generate the HMAC-SHA1 of any string… >>> More