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Co-authored-by: Théo Crevon <[email protected]>

webcrypto/key.go

@@ -2,6 +2,7 @@ package webcrypto
 
 import (
 	"errors"
+	"strings"
 
 	"github.com/grafana/sobek"
 )
@@ -191,7 +192,12 @@ func newKeyGenerator(rt *sobek.Runtime, normalized Algorithm, params sobek.Value
 	case RSASsaPkcs1v15, RSAPss, RSAOaep:
 		kg, err = newRsaHashedKeyGenParams(rt, normalized, params)
 	default:
-		return nil, NewError(NotImplemented, "unsupported algorithm for key generation: "+normalized.Name)
+		validAlgorithms := []string{AESCbc, AESCtr, AESGcm, AESKw, HMAC, ECDH, ECDSA, RSASsaPkcs1v15, RSAPss, RSAOaep}
+		return nil, NewError(
+			NotImplemented,
+			"unsupported key generation algorithm '"+normalized.Name+"', "+
+				"accepted values are: "+strings.Join(validAlgorithms, ", "),
+		)
 	}
 
 	if err != nil {

webcrypto/subtle_crypto.go

@@ -446,7 +446,11 @@ func (sc *SubtleCrypto) Digest(algorithm sobek.Value, data sobek.Value) *sobek.P
 		var ok bool
 		hashFn, ok = getHashFn(normalized.Name)
 		if !ok {
-			return NewError(NotSupportedError, "unsupported algorithm, can't map hash function: "+normalized.Name)
+			return NewError(
+				NotSupportedError,
+				"unsupported digest algorithm '"+normalized.Name+"', "+
+					"accepted values are: SHA-1, SHA-256, SHA-384, and SHA-512",
+			)
 		}
 
 		return nil