This is what I’m using for SHA1: #import <CommonCrypto/CommonDigest.h> + (NSData *)sha1:(NSData *)data { unsigned char hash[CC_SHA1_DIGEST_LENGTH]; if ( CC_SHA1([data bytes], [data length], hash) ) { NSData *sha1 = [NSData dataWithBytes:hash length:CC_SHA1_DIGEST_LENGTH]; return sha1; } return nil; } Replace CC_SHA1 with CC_SHA256 (or whichever you need), as well as CC_SHA1_DIGEST_LENGTH with CC_SHA256_DIGEST_LENGTH.
You make a very common beginners mistake… Putting the libraries you link with in the wrong place on the command line when you build. Dependencies are reversed on the command line, so something that depends on something else should actually be put before what it depends on on the command line. In your example, you … Read more
Here’s how I did it: void sha256_hash_string (unsigned char hash[SHA256_DIGEST_LENGTH], char outputBuffer[65]) { int i = 0; for(i = 0; i < SHA256_DIGEST_LENGTH; i++) { sprintf(outputBuffer + (i * 2), “%02x”, hash[i]); } outputBuffer[64] = 0; } void sha256_string(char *string, char outputBuffer[65]) { unsigned char hash[SHA256_DIGEST_LENGTH]; SHA256_CTX sha256; SHA256_Init(&sha256); SHA256_Update(&sha256, string, strlen(string)); SHA256_Final(hash, &sha256); int … Read more
To hash a string, use the built-in MessageDigest class: import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; import java.nio.charset.StandardCharsets; import java.math.BigInteger; public class CryptoHash { public static void main(String[] args) throws NoSuchAlgorithmException { MessageDigest md = MessageDigest.getInstance(“SHA-256”); String text = “Text to hash, cryptographically.”; // Change this to UTF-16 if needed md.update(text.getBytes(StandardCharsets.UTF_8)); byte[] digest = md.digest(); String hex = … Read more
Don’t use a simple hash, or even a salted hash. Use some sort of key-strengthening technique like bcrypt (with a .NET implementation here) or PBKDF2 (with a built-in implementation). Here’s an example using PBKDF2. To generate a key from your password… string password = GetPasswordFromUserInput(); // specify that we want to randomly generate a 20-byte … Read more
(This is already answered in comments, but since it lacks an actual answer, I’m writing this.) This problem arises in newer versions of Visual C++ (the older versions usually just silently linked the program and it would crash and burn at run time.) It means that some of the libraries you are linking with your … Read more
Neither. You should use bcrypt. The hashes you mention are all optimized to be quick and easy on hardware, and so cracking them share the same qualities. If you have no other choice, at least be sure to use a long salt and re-hash multiple times. Using bcrypt in PHP 5.5+ PHP 5.5 offers new … Read more
openssl dgst -sha256 < data.txt produces something like: (stdin)= b39eaeb437e33087132f01c2abc60c6a16904ee3771cd7b0d622d01061b40729 notice the (stdin)=‘? you don’t want that to be part of your hash, if you need to create a digest, use the -binary option. try using this to sign your data: openssl sha -sha256 -sign private.pem < data.txt This does everything you need. edit – … Read more
You have to convert explicitly between Int and CC_LONG, because Swift does not do implicit conversions, as in (Objective-)C. You also have to define hash as an array of the required size. func sha256(data : NSData) -> NSData { var hash = [UInt8](count: Int(CC_SHA256_DIGEST_LENGTH), repeatedValue: 0) CC_SHA256(data.bytes, CC_LONG(data.length), &hash) let res = NSData(bytes: hash, length: … Read more
OUTDATED: Many modern browsers now have first-class support for crypto operations. See Vitaly Zdanevich’s answer below. The Stanford JS Crypto Library contains an implementation of SHA-256. While crypto in JS isn’t really as well-vetted an endeavor as other implementation platforms, this one is at least partially developed by, and to a certain extent sponsored by, … Read more