Support Ed25519 signing OCSP

[dixyes]

verified with this demo:

package main

import (
	"crypto"
	"crypto/ed25519"
	"crypto/rand"
	"crypto/x509"
	"crypto/x509/pkix"
	"encoding/pem"
	"math/big"
	"os"
	"time"

	"golang.org/x/crypto/ocsp"
)

func genCert() (cert *x509.Certificate, privKey crypto.Signer) {
	_, privKey, err := ed25519.GenerateKey(rand.Reader)
	// privKey, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
	if err != nil {
		panic(err)
	}

	template := &x509.Certificate{
		Subject: pkix.Name{
			CommonName: "OCSP Responder",
		},
		SerialNumber:          big.NewInt(1),
		NotBefore:             time.Now(),
		NotAfter:              time.Now().Add(365 * 24 * time.Hour),
		BasicConstraintsValid: true,
		KeyUsage:              x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature | x509.KeyUsageCRLSign,
		ExtKeyUsage:           []x509.ExtKeyUsage{x509.ExtKeyUsageOCSPSigning},
		IsCA:                  true,
	}
	certBytes, err := x509.CreateCertificate(rand.Reader, template, template, privKey.Public(), privKey)
	if err != nil {
		panic(err)
	}

	cert, err = x509.ParseCertificate(certBytes)
	if err != nil {
		panic(err)
	}

	file, err := os.Create("ca_cert.pem")
	if err != nil {
		panic(err)
	}
	pem.Encode(file, &pem.Block{Type: "CERTIFICATE", Bytes: certBytes})
	file.Close()

	privKeyDER, err := x509.MarshalPKCS8PrivateKey(privKey)
	if err != nil {
		panic(err)
	}

	file, err = os.Create("ca_key.pem")
	if err != nil {
		panic(err)
	}
	pem.Encode(file, &pem.Block{Type: "PRIVATE KEY", Bytes: privKeyDER})
	file.Close()

	return cert, privKey
}

func genResp() {
	caCert, privKey := genCert()

	resp := ocsp.Response{
		Status:       ocsp.Good,
		SerialNumber: big.NewInt(123456789),
		ThisUpdate:   time.Now(),
		NextUpdate:   time.Now().Add(24 * time.Hour),
	}

	respBytes, err := ocsp.CreateResponse(caCert, caCert, resp, privKey)
	if err != nil {
		panic(err)
	}

	os.WriteFile("ocsp_response.der", respBytes, 0644)
}

func main() {
	genResp()
}

and openssl command

openssl ocsp -text -respin ocsp_response.der -issuer ca_cert.pem

OCSP Response Data:
    OCSP Response Status: successful (0x0)
    Response Type: Basic OCSP Response
    Version: 1 (0x0)
    Responder Id: CN = OCSP Responder
    Produced At: Sep  9 03:49:00 2025 GMT
    Responses:
    Certificate ID:
      Hash Algorithm: sha1
      Issuer Name Hash: 31CD3802B3300F488C2D7B829551A7CAC184C429
      Issuer Key Hash: B4174F7BAEA50A5804B34C2BD9DA8D2E3A19129D
      Serial Number: 075BCD15
    Cert Status: good
    This Update: Sep  9 03:49:31 2025 GMT
    Next Update: Sep 10 03:49:31 2025 GMT

    Signature Algorithm: ED25519
    Signature Value:
        53:10:ac:62:3f:08:41:b7:ef:ef:68:c4:b7:fa:01:f1:d8:40:
        ed:83:6d:2e:6d:34:03:4c:46:ef:85:16:58:da:75:f2:bd:4d:
        1f:ef:ce:b2:3a:ea:a3:7e:db:f4:56:7a:ef:76:74:fe:5b:6d:
        be:eb:ad:f3:ad:47:99:4f:3a:0c
Response verify OK

also add go tests for ecdsa and ed25519

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Patch Set 1:

(1 comment)

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[gopherbot]

Message from Daniel McCarney:

Patch Set 1:

(1 comment)

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Message from Yun Dou (dixyes):

Patch Set 1:

(1 comment)

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