SHA256

SHA-256 hash function (RFC 6234) backed by the secp256k1_swift_sha256 shim (Sources/libsecp256k1/src/Utility.c), producing 32-byte SHA256Digest values; also provides BIP-340 tagged-hash support via taggedHash(tag:data:) using upstream secp256k1_tagged_sha256.

iOS 13.0+
macCatalyst 13.0+
macOS 10.15+
tvOS 13.0+
visionOS 1.0+
watchOS 6.0+

enum SHA256

Overview

Re-exported from libsecp256k1’s internal SHA-256 implementation rather than linking a separate hash library — this keeps the cryptographic dependency surface to a single audited component. The same implementation backs upstream signing and verification, so hashes produced here are byte-for-byte identical to the ones consumed by secp256k1_schnorrsig_sign_custom, secp256k1_ecdsa_sign, etc.

Topics

Hashing

static func hash<D>(data: D) -> SHA256Digest
Hashes data with SHA-256 via the secp256k1_swift_sha256 shim and returns a 32-byte SHA256Digest.
static func taggedHash<D>(tag: D, data: D) -> SHA256Digest
Computes a BIP-340 tagged hash SHA256(SHA256(tag) || SHA256(tag) || data) via upstream secp256k1_tagged_sha256, producing a 32-byte SHA256Digest.