byte[] input, String algorithm, SecretKey key, HashFunction hashFunc) throws Exception {
    Mac mac = Mac.getInstance(algorithm);
    mac.init(key);
    mac.update(input);

    assertEquals(HashCode.fromBytes(mac.doFinal()), hashFunc.hashBytes(input));
    assertEquals(HashCode.fromBytes(mac.doFinal(input)), hashFunc.hashBytes(input));
  }

  // Tests from RFC2022: https://tools.ietf.org/html/rfc2202

import (
	"hash"
	"io"
	"strconv"
)

// Hash identifies a cryptographic hash function that is implemented in another
// package.
type Hash uint

// HashFunc simply returns the value of h so that [Hash] implements [SignerOpts].
func (h Hash) HashFunc() Hash {
	return h
}

func (h Hash) String() string {
	switch h {
	case MD4:
		return "MD4"
	case MD5:
		return "MD5"
	case SHA1:
		return "SHA-1"

	return bytes.Clone(priv[:SeedSize])
}

// Sign signs the given message with priv. rand is ignored and can be nil.
//
// If opts.HashFunc() is [crypto.SHA512], the pre-hashed variant Ed25519ph is used
// and message is expected to be a SHA-512 hash, otherwise opts.HashFunc() must
// be [crypto.Hash](0) and the message must not be hashed, as Ed25519 performs two
// passes over messages to be signed.
//

      byte[] input, String algorithm, SecretKey key, HashFunction hashFunc) throws Exception {
    Mac mac = Mac.getInstance(algorithm);
    mac.init(key);
    mac.update(input);

    assertEquals(HashCode.fromBytes(mac.doFinal()), hashFunc.hashBytes(input));
    assertEquals(HashCode.fromBytes(mac.doFinal(input)), hashFunc.hashBytes(input));
  }

  // Tests from RFC2022: https://tools.ietf.org/html/rfc2202

		}
		if err := rsa.VerifyPKCS1v15(pubKey, hashFunc, signed, sig); err != nil {
			return err
		}
	case signatureRSAPSS:
		pubKey, ok := pubkey.(*rsa.PublicKey)
		if !ok {
			return fmt.Errorf("expected an RSA public key, got %T", pubkey)
		}
		signOpts := &rsa.PSSOptions{SaltLength: rsa.PSSSaltLengthEqualsHash}
		if err := rsa.VerifyPSS(pubKey, hashFunc, signed, sig, signOpts); err != nil {
			return err
		}

func prf12(hashFunc func() hash.Hash) func(result, secret, label, seed []byte) {
	return func(result, secret, label, seed []byte) {
		labelAndSeed := make([]byte, len(label)+len(seed))
		copy(labelAndSeed, label)
		copy(labelAndSeed[len(label):], seed)

		pHash(result, secret, labelAndSeed, hashFunc)
	}
}

const (

package ssa

import (
	"fmt"
	"io"
	"strings"

	"cmd/internal/notsha256"
	"cmd/internal/src"
)

func printFunc(f *Func) {
	f.Logf("%s", f)
}

func hashFunc(f *Func) []byte {
	h := notsha256.New()
	p := stringFuncPrinter{w: h, printDead: true}
	fprintFunc(p, f)
	return h.Sum(nil)
}

func (f *Func) String() string {
	var buf strings.Builder

func hashForServerKeyExchange(sigType uint8, hashFunc crypto.Hash, version uint16, slices ...[]byte) []byte {
	if sigType == signatureEd25519 {
		var signed []byte
		for _, slice := range slices {
			signed = append(signed, slice...)
		}
		return signed
	}
	if version >= VersionTLS12 {
		h := hashFunc.New()
		for _, slice := range slices {
			h.Write(slice)
		}

// and deletes as well, especially if the map is larger. It's primary use-case is
// the unique package, but can be used elsewhere as well.
type HashTrieMap[K, V comparable] struct {
	root     *indirect[K, V]
	keyHash  hashFunc
	keyEqual equalFunc
	valEqual equalFunc
	seed     uintptr
}

// NewHashTrieMap creates a new HashTrieMap for the provided key and value.
func NewHashTrieMap[K, V comparable]() *HashTrieMap[K, V] {
	var m map[K]V

	// zero, it overrides the hash function passed to SignPSS. It's required
	// when using PrivateKey.Sign.
	Hash crypto.Hash
}

// HashFunc returns opts.Hash so that [PSSOptions] implements [crypto.SignerOpts].
func (opts *PSSOptions) HashFunc() crypto.Hash {
	return opts.Hash
}

func (opts *PSSOptions) saltLength() int {
	if opts == nil {
		return PSSSaltLengthAuto
	}