OpenSSLDigest: use delegate model

Instead of invoking NativeCrypto directly, delegate to the JCE subsystem
to select the AndroidOpenSSL provider.

Change-Id: I91c01fc5c21c6d674203226a89a9f4fb2f30426f

1 files changed, 26 insertions, 104 deletions

diff --git a/bcprov/src/main/java/org/bouncycastle/crypto/digests/OpenSSLDigest.java b/bcprov/src/main/java/org/bouncycastle/crypto/digests/OpenSSLDigest.java
index 37df370..2846725 100644
--- a/bcprov/src/main/java/org/bouncycastle/crypto/digests/OpenSSLDigest.java
+++ b/bcprov/src/main/java/org/bouncycastle/crypto/digests/OpenSSLDigest.java
@@ -16,151 +16,73 @@
 
 package org.bouncycastle.crypto.digests;
 
-import com.android.org.conscrypt.NativeCrypto;
-import org.bouncycastle.crypto.ExtendedDigest;
+import org.bouncycastle.crypto.Digest;
+import java.security.DigestException;
+import java.security.MessageDigest;
 
 /**
  * Implements the BouncyCastle Digest interface using OpenSSL's EVP API.
  */
-public class OpenSSLDigest implements ExtendedDigest {
-
-    /**
-     * Holds the standard name of the hashing algorithm, e.g. "SHA-1";
-     */
-    private final String algorithm;
-
-    /**
-     * Holds the EVP_MD for the hashing algorithm, e.g. EVP_get_digestbyname("sha1");
-     */
-    private final long evp_md;
-
-    /**
-     * Holds the output size of the message digest.
-     */
-    private final int size;
-
-    /**
-     * Holds the block size of the message digest.
-     */
-    private final int blockSize;
-
-    /**
-     * Holds a pointer to the native message digest context. It is
-     * lazily initialized to avoid having to reallocate on reset when
-     * its unlikely to be reused.
-     */
-    private long ctx;
-
-    /**
-     * Holds a dummy buffer for writing single bytes to the digest.
-     */
-    private final byte[] singleByte = new byte[1];
-
-    /**
-     * Creates a new OpenSSLMessageDigest instance for the given algorithm
-     * name.
-     */
-    private OpenSSLDigest(String algorithm, long evp_md, int size, int blockSize) {
-        this.algorithm = algorithm;
-        this.evp_md = evp_md;
-        this.size = size;
-        this.blockSize = blockSize;
+public class OpenSSLDigest implements Digest {
+    private final MessageDigest delegate;
+
+    public OpenSSLDigest(String algorithm) {
+        try {
+            delegate = MessageDigest.getInstance(algorithm, "AndroidOpenSSL");
+        } catch (Exception e) {
+            throw new RuntimeException(e);
+        }
     }
 
     public String getAlgorithmName() {
-        return algorithm;
+        return delegate.getAlgorithm();
     }
 
     public int getDigestSize() {
-        return size;
-    }
-
-    public int getByteLength() {
-        return blockSize;
+        return delegate.getDigestLength();
     }
 
     public void reset() {
-        free();
+        delegate.reset();
     }
 
     public void update(byte in) {
-        singleByte[0] = in;
-        update(singleByte, 0, 1);
+        delegate.update(in);
     }
 
     public void update(byte[] in, int inOff, int len) {
-        NativeCrypto.EVP_DigestUpdate(getCtx(), in, inOff, len);
+        delegate.update(in, inOff, len);
     }
 
     public int doFinal(byte[] out, int outOff) {
-        int i = NativeCrypto.EVP_DigestFinal(getCtx(), out, outOff);
-        ctx = 0; // EVP_DigestFinal frees the context as a side effect
-        reset();
-        return i;
-    }
-
-    private long getCtx() {
-        if (ctx == 0) {
-            ctx = NativeCrypto.EVP_DigestInit(evp_md);
-        }
-        return ctx;
-    }
-
-    private void free() {
-        if (ctx != 0) {
-            NativeCrypto.EVP_MD_CTX_destroy(ctx);
-            ctx = 0;
-        }
-    }
-
-    @Override
-    protected void finalize() throws Throwable {
         try {
-            free();
-        } finally {
-            super.finalize();
+            return delegate.digest(out, outOff, out.length);
+        } catch (DigestException e) {
+            throw new RuntimeException(e);
         }
     }
 
     public static class MD5 extends OpenSSLDigest {
-        private static final long EVP_MD = NativeCrypto.EVP_get_digestbyname("md5");
-        private static final int SIZE = NativeCrypto.EVP_MD_size(EVP_MD);
-        private static final int BLOCK_SIZE = NativeCrypto.EVP_MD_block_size(EVP_MD);
-        public MD5() { super("MD5", EVP_MD, SIZE, BLOCK_SIZE); }
+        public MD5() { super("MD5"); }
     }
 
     public static class SHA1 extends OpenSSLDigest {
-        private static final long EVP_MD = NativeCrypto.EVP_get_digestbyname("sha1");
-        private static final int SIZE = NativeCrypto.EVP_MD_size(EVP_MD);
-        private static final int BLOCK_SIZE = NativeCrypto.EVP_MD_block_size(EVP_MD);
-        public SHA1() { super("SHA-1", EVP_MD, SIZE, BLOCK_SIZE); }
+        public SHA1() { super("SHA-1"); }
     }
 
     public static class SHA224 extends OpenSSLDigest {
-        private static final long EVP_MD = NativeCrypto.EVP_get_digestbyname("sha224");
-        private static final int SIZE = NativeCrypto.EVP_MD_size(EVP_MD);
-        private static final int BLOCK_SIZE = NativeCrypto.EVP_MD_block_size(EVP_MD);
-        public SHA224() { super("SHA-224", EVP_MD, SIZE, BLOCK_SIZE); }
+        public SHA224() { super("SHA-224"); }
     }
 
     public static class SHA256 extends OpenSSLDigest {
-        private static final long EVP_MD = NativeCrypto.EVP_get_digestbyname("sha256");
-        private static final int SIZE = NativeCrypto.EVP_MD_size(EVP_MD);
-        private static final int BLOCK_SIZE = NativeCrypto.EVP_MD_block_size(EVP_MD);
-        public SHA256() { super("SHA-256", EVP_MD, SIZE, BLOCK_SIZE); }
+        public SHA256() { super("SHA-256"); }
     }
 
     public static class SHA384 extends OpenSSLDigest {
-        private static final long EVP_MD = NativeCrypto.EVP_get_digestbyname("sha384");
-        private static final int SIZE = NativeCrypto.EVP_MD_size(EVP_MD);
-        private static final int BLOCK_SIZE = NativeCrypto.EVP_MD_block_size(EVP_MD);
-        public SHA384() { super("SHA-384", EVP_MD, SIZE, BLOCK_SIZE); }
+        public SHA384() { super("SHA-384"); }
     }
 
     public static class SHA512 extends OpenSSLDigest {
-        private static final long EVP_MD = NativeCrypto.EVP_get_digestbyname("sha512");
-        private static final int SIZE = NativeCrypto.EVP_MD_size(EVP_MD);
-        private static final int BLOCK_SIZE = NativeCrypto.EVP_MD_block_size(EVP_MD);
-        public SHA512() { super("SHA-512", EVP_MD, SIZE, BLOCK_SIZE); }
+        public SHA512() { super("SHA-512"); }
     }
 }