Android通过NDK获取Keystore签名值

package com.boyaa.ndk;

import android.content.Context;

public class RegionGames {
 static {
  try {
   System.loadLibrary("boyaaregiongames");
  } catch (Throwable e) {
   e.printStackTrace();
  }
 }

 public static native String getSign(Context ctx);
}

 

 

#include <jni.h>
#include<android/log.h>
#include <string.h>
#include <unistd.h>

extern "C"
JNIEXPORT jstring JNICALL Java_com_boyaa_ndk_RegionGames_signData(JNIEnv *env, jclass jcl,
  jobject context_object) {
 jclass context_class = env->GetObjectClass(context_object);

  //context.getPackageManager()
  jmethodID methodId = env->GetMethodID(context_class, "getPackageManager", "()Landroid/content/pm/PackageManager;");
  jobject package_manager_object = env->CallObjectMethod(context_object, methodId);
     if (package_manager_object == NULL) {
      __android_log_print(ANDROID_LOG_INFO, "JNITag","getPackageManager() Failed!");
         return NULL;
     }

     //context.getPackageName()
     methodId = env->GetMethodID(context_class, "getPackageName", "()Ljava/lang/String;");
  jstring package_name_string = (jstring)env->CallObjectMethod(context_object, methodId);
  if (package_name_string == NULL) {
   __android_log_print(ANDROID_LOG_INFO, "JNITag","getPackageName() Failed!");
   return NULL;
  }

  env->DeleteLocalRef(context_class);

  //PackageManager.getPackageInfo(Sting, int)
  jclass pack_manager_class = env->GetObjectClass(package_manager_object);
  methodId = env->GetMethodID(pack_manager_class, "getPackageInfo", "(Ljava/lang/String;I)Landroid/content/pm/PackageInfo;");
  env->DeleteLocalRef(pack_manager_class);
  jobject package_info_object = env->CallObjectMethod(package_manager_object, methodId, package_name_string, 64);
  if (package_info_object == NULL) {
   __android_log_print(ANDROID_LOG_INFO, "JNITag","getPackageInfo() Failed!");
   return NULL;
  }

  env->DeleteLocalRef(package_manager_object);

  //PackageInfo.signatures[0]
  jclass package_info_class = env->GetObjectClass(package_info_object);
  jfieldID fieldId = env->GetFieldID(package_info_class, "signatures", "[Landroid/content/pm/Signature;");
  env->DeleteLocalRef(package_info_class);
  jobjectArray signature_object_array = (jobjectArray)env->GetObjectField(package_info_object, fieldId);
  if (signature_object_array == NULL) {
   __android_log_print(ANDROID_LOG_INFO, "JNITag","PackageInfo.signatures[] is null");
   return NULL;
  }
  jobject signature_object = env->GetObjectArrayElement(signature_object_array, 0);

  env->DeleteLocalRef(package_info_object);

  //Signature.toCharsString()
  jclass signature_class = env->GetObjectClass(signature_object);
  methodId = env->GetMethodID(signature_class, "toCharsString", "()Ljava/lang/String;");
  env->DeleteLocalRef(signature_class);
  jstring signature_string = (jstring) env->CallObjectMethod(signature_object, methodId);

  return signature_string;
}