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authorPieter Wuille <pieter.wuille@gmail.com>2014-11-18 18:06:36 +0100
committerPieter Wuille <pieter.wuille@gmail.com>2014-11-18 18:06:36 +0100
commitd48555b36ac512161b81f9b6bca7bea16a0cd806 (patch)
treec5a4740019e4642df6ce068317541cad01202e06 /src/java
Squashed 'src/secp256k1/' content from commit ad2028f
git-subtree-dir: src/secp256k1 git-subtree-split: ad2028f9890ca40bdd32055aa0fe5c1c9af0e485
Diffstat (limited to 'src/java')
-rw-r--r--src/java/org/bitcoin/NativeSecp256k1.java60
-rw-r--r--src/java/org_bitcoin_NativeSecp256k1.c23
-rw-r--r--src/java/org_bitcoin_NativeSecp256k1.h21
3 files changed, 104 insertions, 0 deletions
diff --git a/src/java/org/bitcoin/NativeSecp256k1.java b/src/java/org/bitcoin/NativeSecp256k1.java
new file mode 100644
index 0000000000..90a498eaa2
--- /dev/null
+++ b/src/java/org/bitcoin/NativeSecp256k1.java
@@ -0,0 +1,60 @@
+package org.bitcoin;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+import com.google.common.base.Preconditions;
+
+
+/**
+ * This class holds native methods to handle ECDSA verification.
+ * You can find an example library that can be used for this at
+ * https://github.com/sipa/secp256k1
+ */
+public class NativeSecp256k1 {
+ public static final boolean enabled;
+ static {
+ boolean isEnabled = true;
+ try {
+ System.loadLibrary("javasecp256k1");
+ } catch (UnsatisfiedLinkError e) {
+ isEnabled = false;
+ }
+ enabled = isEnabled;
+ }
+
+ private static ThreadLocal<ByteBuffer> nativeECDSABuffer = new ThreadLocal<ByteBuffer>();
+ /**
+ * Verifies the given secp256k1 signature in native code.
+ * Calling when enabled == false is undefined (probably library not loaded)
+ *
+ * @param data The data which was signed, must be exactly 32 bytes
+ * @param signature The signature
+ * @param pub The public key which did the signing
+ */
+ public static boolean verify(byte[] data, byte[] signature, byte[] pub) {
+ Preconditions.checkArgument(data.length == 32 && signature.length <= 520 && pub.length <= 520);
+
+ ByteBuffer byteBuff = nativeECDSABuffer.get();
+ if (byteBuff == null) {
+ byteBuff = ByteBuffer.allocateDirect(32 + 8 + 520 + 520);
+ byteBuff.order(ByteOrder.nativeOrder());
+ nativeECDSABuffer.set(byteBuff);
+ }
+ byteBuff.rewind();
+ byteBuff.put(data);
+ byteBuff.putInt(signature.length);
+ byteBuff.putInt(pub.length);
+ byteBuff.put(signature);
+ byteBuff.put(pub);
+ return secp256k1_ecdsa_verify(byteBuff) == 1;
+ }
+
+ /**
+ * @param byteBuff signature format is byte[32] data,
+ * native-endian int signatureLength, native-endian int pubkeyLength,
+ * byte[signatureLength] signature, byte[pubkeyLength] pub
+ * @returns 1 for valid signature, anything else for invalid
+ */
+ private static native int secp256k1_ecdsa_verify(ByteBuffer byteBuff);
+}
diff --git a/src/java/org_bitcoin_NativeSecp256k1.c b/src/java/org_bitcoin_NativeSecp256k1.c
new file mode 100644
index 0000000000..bb4cd70728
--- /dev/null
+++ b/src/java/org_bitcoin_NativeSecp256k1.c
@@ -0,0 +1,23 @@
+#include "org_bitcoin_NativeSecp256k1.h"
+#include "include/secp256k1.h"
+
+JNIEXPORT jint JNICALL Java_org_bitcoin_NativeSecp256k1_secp256k1_1ecdsa_1verify
+ (JNIEnv* env, jclass classObject, jobject byteBufferObject)
+{
+ unsigned char* data = (unsigned char*) (*env)->GetDirectBufferAddress(env, byteBufferObject);
+ int sigLen = *((int*)(data + 32));
+ int pubLen = *((int*)(data + 32 + 4));
+
+ return secp256k1_ecdsa_verify(data, 32, data+32+8, sigLen, data+32+8+sigLen, pubLen);
+}
+
+static void __javasecp256k1_attach(void) __attribute__((constructor));
+static void __javasecp256k1_detach(void) __attribute__((destructor));
+
+static void __javasecp256k1_attach(void) {
+ secp256k1_start(SECP256K1_START_VERIFY);
+}
+
+static void __javasecp256k1_detach(void) {
+ secp256k1_stop();
+}
diff --git a/src/java/org_bitcoin_NativeSecp256k1.h b/src/java/org_bitcoin_NativeSecp256k1.h
new file mode 100644
index 0000000000..d7fb004fa8
--- /dev/null
+++ b/src/java/org_bitcoin_NativeSecp256k1.h
@@ -0,0 +1,21 @@
+/* DO NOT EDIT THIS FILE - it is machine generated */
+#include <jni.h>
+/* Header for class org_bitcoin_NativeSecp256k1 */
+
+#ifndef _Included_org_bitcoin_NativeSecp256k1
+#define _Included_org_bitcoin_NativeSecp256k1
+#ifdef __cplusplus
+extern "C" {
+#endif
+/*
+ * Class: org_bitcoin_NativeSecp256k1
+ * Method: secp256k1_ecdsa_verify
+ * Signature: (Ljava/nio/ByteBuffer;)I
+ */
+JNIEXPORT jint JNICALL Java_org_bitcoin_NativeSecp256k1_secp256k1_1ecdsa_1verify
+ (JNIEnv *, jclass, jobject);
+
+#ifdef __cplusplus
+}
+#endif
+#endif