Add support for ML-DSA keys

CHANGELOG.md

@@ -25,6 +25,17 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ---
 
+## [TPB] - TBD
+
+### Added
+
+- Support for ML-DSA (FIPS 204) keys, available when built with Go 1.27 or
+  newer. JOSE-based flows (JWK, JWS and JWT tokens) do not support ML-DSA yet.
+
+### Deprecated
+
+- Go 1.25 support. Go 1.26 or newer is now required.
+
 ## [0.30.2] - 2026-03-22
 
 - Update golang.org/grpc to patch security advisory

acme/account.go

@@ -19,7 +19,7 @@ type Account struct {
 	Contact                []string         `json:"contact,omitempty"`
 	Status                 Status           `json:"status"`
 	OrdersURL              string           `json:"orders"`
-	ExternalAccountBinding interface{}      `json:"externalAccountBinding,omitempty"`
+	ExternalAccountBinding any              `json:"externalAccountBinding,omitempty"`
 	LocationPrefix         string           `json:"-"`
 	ProvisionerID          string           `json:"-"`
 	ProvisionerName        string           `json:"-"`
@@ -34,7 +34,7 @@ func (a *Account) GetLocation() string {
 }
 
 // ToLog enables response logging.
-func (a *Account) ToLog() (interface{}, error) {
+func (a *Account) ToLog() (any, error) {
 	b, err := json.Marshal(a)
 	if err != nil {
 		return nil, WrapErrorISE(err, "error marshaling account for logging")
@@ -112,7 +112,7 @@ type ExternalAccountKey struct {
 	AccountID     string    `json:"-"`
 	HmacKey       []byte    `json:"-"`
 	CreatedAt     time.Time `json:"createdAt"`
-	BoundAt       time.Time `json:"boundAt,omitempty"`
+	BoundAt       time.Time `json:"boundAt,omitzero"`
 	Policy        *Policy   `json:"policy,omitempty"`
 }
 

acme/api/account.go

@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"errors"
 	"net/http"
+	"slices"
 
 	"github.com/go-chi/chi/v5"
 
@@ -22,10 +23,8 @@ type NewAccountRequest struct {
 }
 
 func validateContacts(cs []string) error {
-	for _, c := range cs {
-		if c == "" {
-			return acme.NewError(acme.ErrorMalformedType, "contact cannot be empty string")
-		}
+	if slices.Contains(cs, "") {
+		return acme.NewError(acme.ErrorMalformedType, "contact cannot be empty string")
 	}
 	return nil
 }
@@ -218,7 +217,7 @@ func GetOrUpdateAccount(w http.ResponseWriter, r *http.Request) {
 
 func logOrdersByAccount(w http.ResponseWriter, oids []string) {
 	if rl, ok := w.(logging.ResponseLogger); ok {
-		m := map[string]interface{}{
+		m := map[string]any{
 			"orders": oids,
 		}
 		rl.WithFields(m)

acme/api/account_test.go

@@ -120,7 +120,7 @@ func createEABJWS(jwk *jose.JSONWebKey, hmacKey []byte, keyID, u string) (*jose.
 			Key:       hmacKey,
 		},
 		&jose.SignerOptions{
-			ExtraHeaders: map[jose.HeaderKey]interface{}{
+			ExtraHeaders: map[jose.HeaderKey]any{
 				"kid": keyID,
 				"url": u,
 			},

acme/api/eab.go

@@ -53,8 +53,7 @@ func validateExternalAccountBinding(ctx context.Context, nar *NewAccountRequest)
 	db := acme.MustDatabaseFromContext(ctx)
 	externalAccountKey, err := db.GetExternalAccountKey(ctx, acmeProv.ID, keyID)
 	if err != nil {
-		var ae *acme.Error
-		if errors.As(err, &ae) {
+		if _, ok := errors.AsType[*acme.Error](err); ok {
 			return nil, acme.WrapError(acme.ErrorUnauthorizedType, err, "the field 'kid' references an unknown key")
 		}
 		return nil, acme.WrapErrorISE(err, "error retrieving external account key")

acme/api/handler.go

@@ -209,7 +209,7 @@ type Directory struct {
 }
 
 // ToLog enables response logging for the Directory type.
-func (d *Directory) ToLog() (interface{}, error) {
+func (d *Directory) ToLog() (any, error) {
 	b, err := json.Marshal(d)
 	if err != nil {
 		return nil, acme.WrapErrorISE(err, "error marshaling directory for logging")

acme/api/middleware.go

@@ -8,6 +8,7 @@ import (
 	"net/http"
 	"net/url"
 	"path"
+	"slices"
 	"strings"
 
 	"go.step.sm/crypto/jose"
@@ -23,7 +24,7 @@ type nextHTTP = func(http.ResponseWriter, *http.Request)
 
 func logNonce(w http.ResponseWriter, nonce string) {
 	if rl, ok := w.(logging.ResponseLogger); ok {
-		m := map[string]interface{}{
+		m := map[string]any{
 			"nonce": nonce,
 		}
 		rl.WithFields(m)
@@ -82,11 +83,9 @@ func verifyContentType(next nextHTTP) nextHTTP {
 		}
 
 		ct := r.Header.Get("Content-Type")
-		for _, e := range expected {
-			if ct == e {
-				next(w, r)
-				return
-			}
+		if slices.Contains(expected, ct) {
+			next(w, r)
+			return
 		}
 		render.Error(w, r, acme.NewError(acme.ErrorMalformedType,
 			"expected content-type to be in %s, but got %s", expected, ct))

acme/api/middleware_test.go

@@ -30,7 +30,7 @@ func testNext(w http.ResponseWriter, _ *http.Request) {
 	w.Write(testBody)
 }
 
-func newBaseContext(ctx context.Context, args ...interface{}) context.Context {
+func newBaseContext(ctx context.Context, args ...any) context.Context {
 	for _, a := range args {
 		switch v := a.(type) {
 		case acme.DB:
@@ -1269,7 +1269,7 @@ func TestHandler_validateJWS(t *testing.T) {
 						Protected: jose.Header{
 							Algorithm:  jose.RS256,
 							JSONWebKey: &pub,
-							ExtraHeaders: map[jose.HeaderKey]interface{}{
+							ExtraHeaders: map[jose.HeaderKey]any{
 								"url": u,
 							},
 						},
@@ -1299,7 +1299,7 @@ func TestHandler_validateJWS(t *testing.T) {
 						Protected: jose.Header{
 							Algorithm:  jose.RS256,
 							JSONWebKey: &pub,
-							ExtraHeaders: map[jose.HeaderKey]interface{}{
+							ExtraHeaders: map[jose.HeaderKey]any{
 								"url": u,
 							},
 						},
@@ -1357,7 +1357,7 @@ func TestHandler_validateJWS(t *testing.T) {
 					{
 						Protected: jose.Header{
 							Algorithm: jose.ES256,
-							ExtraHeaders: map[jose.HeaderKey]interface{}{
+							ExtraHeaders: map[jose.HeaderKey]any{
 								"url": "foo",
 							},
 						},
@@ -1386,7 +1386,7 @@ func TestHandler_validateJWS(t *testing.T) {
 							Algorithm:  jose.ES256,
 							KeyID:      "bar",
 							JSONWebKey: &pub,
-							ExtraHeaders: map[jose.HeaderKey]interface{}{
+							ExtraHeaders: map[jose.HeaderKey]any{
 								"url": u,
 							},
 						},
@@ -1410,7 +1410,7 @@ func TestHandler_validateJWS(t *testing.T) {
 					{
 						Protected: jose.Header{
 							Algorithm: jose.ES256,
-							ExtraHeaders: map[jose.HeaderKey]interface{}{
+							ExtraHeaders: map[jose.HeaderKey]any{
 								"url": u,
 							},
 						},
@@ -1435,7 +1435,7 @@ func TestHandler_validateJWS(t *testing.T) {
 						Protected: jose.Header{
 							Algorithm: jose.ES256,
 							KeyID:     "bar",
-							ExtraHeaders: map[jose.HeaderKey]interface{}{
+							ExtraHeaders: map[jose.HeaderKey]any{
 								"url": u,
 							},
 						},
@@ -1465,7 +1465,7 @@ func TestHandler_validateJWS(t *testing.T) {
 						Protected: jose.Header{
 							Algorithm:  jose.ES256,
 							JSONWebKey: &pub,
-							ExtraHeaders: map[jose.HeaderKey]interface{}{
+							ExtraHeaders: map[jose.HeaderKey]any{
 								"url": u,
 							},
 						},
@@ -1495,7 +1495,7 @@ func TestHandler_validateJWS(t *testing.T) {
 						Protected: jose.Header{
 							Algorithm:  jose.RS256,
 							JSONWebKey: &pub,
-							ExtraHeaders: map[jose.HeaderKey]interface{}{
+							ExtraHeaders: map[jose.HeaderKey]any{
 								"url": u,
 							},
 						},

acme/api/order.go

@@ -26,8 +26,8 @@ import (
 // NewOrderRequest represents the body for a NewOrder request.
 type NewOrderRequest struct {
 	Identifiers []acme.Identifier `json:"identifiers"`
-	NotBefore   time.Time         `json:"notBefore,omitempty,omitzero"`
-	NotAfter    time.Time         `json:"notAfter,omitempty,omitzero"`
+	NotBefore   time.Time         `json:"notBefore,omitzero"`
+	NotAfter    time.Time         `json:"notAfter,omitzero"`
 }
 
 // Validate validates a new-order request body.
@@ -310,8 +310,8 @@ func newACMEPolicyEngine(eak *acme.ExternalAccountKey) (policy.X509Policy, error
 }
 
 func trimIfWildcard(value string) (string, bool) {
-	if strings.HasPrefix(value, "*.") {
-		return strings.TrimPrefix(value, "*."), true
+	if after, ok := strings.CutPrefix(value, "*."); ok {
+		return after, true
 	}
 	return value, false
 }

acme/api/revoke.go

@@ -212,7 +212,7 @@ func wrapUnauthorizedError(cert *x509.Certificate, unauthorizedIdentifiers []acm
 // logRevoke logs successful revocation of certificate
 func logRevoke(w http.ResponseWriter, ri *authority.RevokeOptions) {
 	if rl, ok := w.(logging.ResponseLogger); ok {
-		rl.WithFields(map[string]interface{}{
+		rl.WithFields(map[string]any{
 			"serial":      ri.Serial,
 			"reasonCode":  ri.ReasonCode,
 			"reason":      ri.Reason,

acme/api/revoke_test.go

@@ -37,8 +37,10 @@ import (
 )
 
 // v is a utility function to return the pointer to an integer
+//
+//go:fix inline
 func v(v int) *int {
-	return &v
+	return new(v)
 }
 
 func generateSerial() (*big.Int, error) {
@@ -47,7 +49,6 @@ func generateSerial() (*big.Int, error) {
 
 // generateCertKeyPair generates fresh x509 certificate/key pairs for testing
 func generateCertKeyPair() (*x509.Certificate, crypto.Signer, error) {
-
 	pub, priv, err := keyutil.GenerateKeyPair("EC", "P-256", 0)
 	if err != nil {
 		return nil, nil, err
@@ -103,7 +104,7 @@ const noKeyID = keyID("")
 // If nonce is empty, it will not be encoded into the header.
 // Implementation taken from github.com/mholt/acmez, which seems to be based on
 // https://github.com/golang/crypto/blob/master/acme/jws.go.
-func jwsEncodeJSON(claimset interface{}, key crypto.Signer, kid keyID, nonce, u string) ([]byte, error) {
+func jwsEncodeJSON(claimset any, key crypto.Signer, kid keyID, nonce, u string) ([]byte, error) {
 	alg, sha := jwsHasher(key.Public())
 	if alg == "" || !sha.Available() {
 		return nil, errUnsupportedKey
@@ -236,14 +237,12 @@ func jwkEncode(pub crypto.PublicKey) (string, error) {
 		if p.BitSize%8 != 0 {
 			n++
 		}
-		x := pub.X.Bytes()
-		if n > len(x) {
-			x = append(make([]byte, n-len(x)), x...)
-		}
-		y := pub.Y.Bytes()
-		if n > len(y) {
-			y = append(make([]byte, n-len(y)), y...)
+		b, err := pub.Bytes()
+		if err != nil {
+			return "", err
 		}
+		x, y := b[1:n+1], b[n+1:]
+
 		// Field order is important.
 		// See https://tools.ietf.org/html/rfc7638#section-3.3 for details.
 		return fmt.Sprintf(`{"crv":%q,"kty":"EC","x":%q,"y":%q}`,
@@ -331,17 +330,17 @@ func Test_validateReasonCode(t *testing.T) {
 		},
 		{
 			name:       "fail/too-low",
-			reasonCode: v(-1),
+			reasonCode: new(-1),
 			want:       acme.NewError(acme.ErrorBadRevocationReasonType, "reasonCode out of bounds"),
 		},
 		{
 			name:       "fail/too-high",
-			reasonCode: v(11),
+			reasonCode: new(11),
 			want:       acme.NewError(acme.ErrorBadRevocationReasonType, "reasonCode out of bounds"),
 		},
 		{
 			name:       "fail/missing-7",
-			reasonCode: v(7),
+			reasonCode: new(7),
 
 			want: acme.NewError(acme.ErrorBadRevocationReasonType, "reasonCode out of bounds"),
 		},
@@ -509,7 +508,7 @@ func TestHandler_RevokeCert(t *testing.T) {
 				Protected: jose.Header{
 					Algorithm: jose.ES256,
 					KeyID:     "bar",
-					ExtraHeaders: map[jose.HeaderKey]interface{}{
+					ExtraHeaders: map[jose.HeaderKey]any{
 						"url": revokeURL,
 					},
 				},
@@ -788,7 +787,7 @@ func TestHandler_RevokeCert(t *testing.T) {
 			assert.FatalError(t, err)
 			jwsPayload := &revokePayload{
 				Certificate: base64.RawURLEncoding.EncodeToString(cert.Raw),
-				ReasonCode:  v(2),
+				ReasonCode:  new(2),
 			}
 			jwsBytes, err := jwsEncodeJSON(rp, unauthorizedKey, "", "nonce", revokeURL)
 			assert.FatalError(t, err)
@@ -888,7 +887,7 @@ func TestHandler_RevokeCert(t *testing.T) {
 		"fail/invalid-reasoncode": func(t *testing.T) test {
 			invalidReasonPayload := &revokePayload{
 				Certificate: base64.RawURLEncoding.EncodeToString(cert.Raw),
-				ReasonCode:  v(7),
+				ReasonCode:  new(7),
 			}
 			invalidReasonCodePayloadBytes, err := json.Marshal(invalidReasonPayload)
 			assert.FatalError(t, err)

acme/authorization.go

@@ -21,7 +21,7 @@ type Authorization struct {
 }
 
 // ToLog enables response logging.
-func (az *Authorization) ToLog() (interface{}, error) {
+func (az *Authorization) ToLog() (any, error) {
 	b, err := json.Marshal(az)
 	if err != nil {
 		return nil, WrapErrorISE(err, "error marshaling authz for logging")