JNI: get ASN algo enum values dynamically in static class block, more flexible if native enum values change

Author: cconlon

jni/include/com_wolfssl_wolfcrypt_Asn.h

@@ -35,6 +35,36 @@
 /* #define WOLFCRYPT_JNI_DEBUG_ON */
 #include <wolfcrypt_jni_debug.h>
 
+JNIEXPORT jint JNICALL Java_com_wolfssl_wolfcrypt_Asn_getDSAk
+  (JNIEnv* env, jclass class)
+{
+    return DSAk;
+}
+
+JNIEXPORT jint JNICALL Java_com_wolfssl_wolfcrypt_Asn_getRSAk
+  (JNIEnv* env, jclass class)
+{
+    return RSAk;
+}
+
+JNIEXPORT jint JNICALL Java_com_wolfssl_wolfcrypt_Asn_getRSAPSSk
+  (JNIEnv* env, jclass class)
+{
+    return RSAPSSk;
+}
+
+JNIEXPORT jint JNICALL Java_com_wolfssl_wolfcrypt_Asn_getRSAESOAEPk
+  (JNIEnv* env, jclass class)
+{
+    return RSAESOAEPk;
+}
+
+JNIEXPORT jint JNICALL Java_com_wolfssl_wolfcrypt_Asn_getECDSAk
+  (JNIEnv* env, jclass class)
+{
+    return ECDSAk;
+}
+
 JNIEXPORT void JNICALL Java_com_wolfssl_wolfcrypt_Asn_encodeSignature__Ljava_nio_ByteBuffer_2Ljava_nio_ByteBuffer_2JI(
     JNIEnv* env, jclass class, jobject encoded_object, jobject hash_object,
     jlong hashSize, jint hashOID)

jni/jni_asn.c

@@ -661,16 +661,14 @@ public synchronized Key engineGetKey(String alias, char[] password)
                         "unprotected key");
                 }
 
-                switch (algoId) {
-                    case Asn.RSAk:
-                        keyFact = KeyFactory.getInstance("RSA");
-                        break;
-                    case Asn.ECDSAk:
-                        keyFact = KeyFactory.getInstance("EC");
-                        break;
-                    default:
-                        throw new NoSuchAlgorithmException(
-                            "Only RSA and EC private key encoding supported");
+                if (algoId == Asn.RSAk) {
+                    keyFact = KeyFactory.getInstance("RSA");
+                } else if (algoId == Asn.ECDSAk) {
+                    keyFact = KeyFactory.getInstance("EC");
+                } else {
+                    throw new NoSuchAlgorithmException(
+                        "Only RSA and EC private key encoding " +
+                        "supported: " + algoId);
                 }
 
                 try {

src/main/java/com/wolfssl/provider/jce/WolfSSLKeyStore.java

@@ -36,18 +36,38 @@ public class Asn extends WolfObject {
     /* Key Sum values, from asn.h Key_Sum enum */
 
     /** DSA key value, from asn.h Key_Sum enum */
-    public static final int DSAk = 515;
+    public static final int DSAk;
     /** RSA key value, from asn.h Key_Sum enum */
-    public static final int RSAk = 645;
+    public static final int RSAk;
     /** RSA-PSS key value, from asn.h Key_Sum enum */
-    public static final int RSAPSSk = 654;
+    public static final int RSAPSSk;
     /** RSA-OAEP key value, from asn.h Key_Sum enum */
-    public static final int RSAESOAEPk = 651;
+    public static final int RSAESOAEPk;
     /** ECDSA key value, from asn.h Key_Sum enum */
-    public static final int ECDSAk = 518;
+    public static final int ECDSAk;
 
-    /** Default Asn constructor */
-    public Asn() { }
+    static {
+        DSAk = getDSAk();
+        RSAk = getRSAk();
+        RSAPSSk = getRSAPSSk();
+        RSAESOAEPk = getRSAESOAEPk();
+        ECDSAk = getECDSAk();
+    }
+
+    /** Return value of native DSAk enum */
+    private static native int getDSAk();
+
+    /** Return value of native RSAk enum */
+    private static native int getRSAk();
+
+    /** Return value of native RSAPSSk enum */
+    private static native int getRSAPSSk();
+
+    /** Return value of native RSAESOAEPk enum */
+    private static native int getRSAESOAEPk();
+
+    /** Return value of native ECDSAk enum */
+    private static native int getECDSAk();
 
     /** ASN.1 encode message digest, before it is signed
      *