DKNet

SHA content hashing

Part of DKNet.Svc.Encryption. IShaHashing computes and verifies SHA-256/512 digests over UTF-8 input, returning hexadecimal strings.

using DKNet.Svc.Encryption.Hashing;

IShaHashing shaHashing = new ShaHashing();
var hash = shaHashing.ComputeSha256("hello world");
var matches = shaHashing.VerifySha256("hello world", hash);
Console.WriteLine(matches); // True

Output is lower-case hex unless upperCase is set. Verification is hex-only (expectedHex), constant-time, and returns false — instead of throwing — when the expected value isn’t valid hex. Empty string input is allowed; null throws ArgumentNullException.

VerifySha256 recomputes the hash and compares the decoded bytes with FixedTimeEquals; equal bytes return true, unequal bytes or invalid hex return false without throwing.

The diagram cannot show ComputeSha256/ComputeSha512 used on their own (without verification) — that path is the first half of the diagram: UTF-8 bytes in, hex string out, no comparison involved.

⚙️ Configuration reference

Member	Parameter	Default	Effect
`ComputeSha256`/`ComputeSha512`	`upperCase`	`false`	`true` returns upper-case hex.
`VerifySha256`/`VerifySha512`	`ignoreCase`	`true`	No effect — comparison runs on decoded bytes, which are already case-insensitive.

IShaHashing has no DI-level configuration: AddEncryptionServices() registers it as transient with no arguments.

⚠️ Gotchas & limits

ignoreCase on VerifySha256/VerifySha512 is a no-op. Comparison is done on decoded bytes, so case never matters — don’t read the parameter as a behavior switch.
IShaHashing is not IDisposable. It’s a stateless wrapper over the static System.Security.Cryptography hash APIs — no using needed, unlike IAesGcmEncryption/IRsaEncryption.
No streaming or byte[] surface. Input and output are both strings; a large payload is hashed as one UTF-8 conversion.

This site is open source. Improve this page.