Thanks for michalk’s comment. The short answer is: The “digest” is a hash of the manifest, introduced in Docker registry v2. The image ID is a hash of the local image JSON configuration.
Both SHA256 and MDA5 are hashing algorithms. They take your input data, in this case your file, and output a 256/128-bit number. This number is a checksum. There is no encryption taking place because an infinite number of inputs can result in the same hash value, although in reality collisions are rare. SHA256 takes somewhat … 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
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
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
SHA-256 isn’t an “encoding” – it’s a one-way hash. You’d basically convert the string into bytes (e.g. using text.getBytes(StandardCharsets.UTF_8)) and then hash the bytes. Note that the result of the hash would also be arbitrary binary data, and if you want to represent that in a string, you should use base64 or hex… don’t try … 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
On https://developer.mozilla.org/en-US/docs/Web/API/SubtleCrypto/digest I found this snippet that uses internal js module: async function sha256(message) { // encode as UTF-8 const msgBuffer = new TextEncoder().encode(message); // hash the message const hashBuffer = await crypto.subtle.digest(‘SHA-256’, msgBuffer); // convert ArrayBuffer to Array const hashArray = Array.from(new Uint8Array(hashBuffer)); // convert bytes to hex string const hashHex = hashArray.map(b => … Read more
Encoding.Unicode is Microsoft’s misleading name for UTF-16 (a double-wide encoding, used in the Windows world for historical reasons but not used by anyone else). http://msdn.microsoft.com/en-us/library/system.text.encoding.unicode.aspx If you inspect your bytes array, you’ll see that every second byte is 0x00 (because of the double-wide encoding). You should be using Encoding.UTF8.GetBytes instead. But also, you will see … Read more
SHA-256 isn’t an “encoding” – it’s a one-way hash. You’d basically convert the string into bytes (e.g. using text.getBytes(StandardCharsets.UTF_8)) and then hash the bytes. Note that the result of the hash would also be arbitrary binary data, and if you want to represent that in a string, you should use base64 or hex… don’t try … Read more