在線SHA1散列發生器

I'm trying to find a hash collision of my modified hash function. Assuming my modified hash only outputs the first 36 bits of SHA-1. As we know, SHA-1 is a 160-bit hash value, hence, we only need to output 9 characters out of 40 characters for comparison.

How i begin my program is by hashing a string (I have a SHA-1 algorithm running and i will name it as sha1. I have also ensured that the output of the SHA-1 algorithm is correct.)

Firstly, i would hardcode 2 string and extract out 9 characters out of 40 characters since i require only the first 36 bits of SHA-1. The function below basically return a true if a collision is found and false if a collision is not found

public static boolean findCollision(int x1, int x2) {    String message1 = "I tried " + x1 + " iteration to find a collision";    String message2 = "I tried " + x2 + " iteration to find a collision";           //hashing my string and extracting 9 characters    String message_hash1 = sha1(message1);    String message_hash2 = sha1(message2);    String modified_hash1 = message_hash1.substring(0, 9);    String modified_hash2 = message_hash2.substring(0, 9);    if (modified_hash1.equals(modified_hash2))          return true;     else         return false;}

Lastly, i will have a main function that will random Integers up to MAX_VALUE in a infinite loop and will break out if and only if a hash is found.

public static void main(String[] args) {    Random random = new Random();    int x1 = 0;    int x2 = 0;    int counter = 0;    while (true) {        while(true){            x1 = random.nextInt(Integer.MAX_VALUE);            x2 = random.nextInt(Integer.MAX_VALUE);            if (x1 != x2)                 break;          }         if (findCollision(x1, x2) == true) {            break;        }        counter++;    }    System.out.println("\nNumber of trials: " + counter);}

If i tried taking only the first 24 bits of SHA-1, i could easily find a collision. However, i'm unable to find a collision for 36 bits instead despite running it for hours. Hence, I'm wondering what is other alternative way for me to find a collision with just 36 bits of SHA-1.

In Objective C I've been using the following code to hash a string:

-(NSString *) sha1:(NSString*)stringToHash {        const char *cStr = [stringToHash UTF8String];    unsigned char result[20];    CC_SHA1( cStr, strlen(cStr), result );    return [NSString stringWithFormat:@"%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X",        result[0], result[1], result[2], result[3],         result[4], result[5], result[6], result[7],        result[8], result[9], result[10], result[11],        result[12], result[13], result[14], result[15],        result[16], result[17], result[18], result[19]        ];  }

Now I need the same for Android but can't find out how to do it. I've been looking for example at this: Make SHA1 encryption on Android? but that doesn't give me the same result as on iPhone. Can anyone point me in the right direction?

I am doing double hashing of few parameters and the 2nd hashed value I want to use in my jmeter script as a parameter.But my output is not getting into the parameter value.Please help

I have written the hash function of the variables in a Beanshell Sampler and I am getting the output.But that is not getting into the request parameter

import java.util.*;import java.security.MessageDigest;String UserID16= vars.get("UID16");String passwordToHash16 = 'test123' ;String IBSKey16 = 'IBSKey' ;String RanNum16 = vars.get("RandomNum16");String hash1st = ${__digest(SHA-1,${UID16}test123IBSKey)} ;String hash2nd = ${__digest(SHA-1,${Hash1st}${RandomNum16})} ;vars.put("hashPassword16", hash2nd);

${hashPassword16} variable I am passing in the request parameter value. That should give me the 2nd Hashed value. But that is just passed as hashPassword16.

I have a website that connects to another external website and passes ID numbers, the page I am working on and that generates the links is written in c#, whereas the target website is written in Java and I am experiences some mismatches

I am trying to use the same approach in C# as the code in Java to encrypt the ID's, the code looks like this:

public static String shaHash(String input) throws NoSuchAlgorithmException {  if (input == null) {    return null;  }  MessageDigest sha = MessageDigest.getInstance("SHA");  try {    sha.update(input.getBytes("UTF8"));    BigInteger hash = new BigInteger(1, sha.digest());    return hash.toString(16);  } catch (UnsupportedEncodingException e) {}  return null;}

And the C# code looks like

StringBuilder convertedId = new StringBuilder();            var idToByte = Encoding.ASCII.GetBytes(id);            using (SHA1 sha1 = SHA1.Create())            {                var bytes = sha1.ComputeHash(idToByte);                for (int i = 0; i < bytes.Length; i++)                {                    convertedId.Append(bytes[i].ToString("x2"));                }            }            return convertedId.ToString();

But the return values are different as the C# code seems like it is adding an extra 0 at the beginning:

Java: b83caf2f739209c42a8d02df0f6d4794f288703, and C#: 0b83caf2f739209c42a8d02df0f6d4794f288703

What would it be the problem? I have tried to change the encoding in the C# code for UTF8 but still doesn't work.

Any ideas guys?

Many thanks in advance

I'm trying to create a dynamic link in Firebase, when I'm selecting the android app, it shows an error saying "Add SHA-1 to this android app", I've already added a credential, but I'm not sure how exactly do I "add SHA-1 to the app"

How is this done?