md5与sha-1的原理及其实现 - 如何计算Android本地已安装应用的MD5指纹并与服务端进行校验？

Question

有需求，要获取自身应用程序的签名，与服务器进行校验比对.
服务器保存的签名是直接从android包中提取出来的签名MD5指纹，如下：

而我本地通过网上搜寻的方法，获取到的签名信息的方法是这样子的：

 private String getSign(Context context) { 
        PackageManager pm = context.getPackageManager(); 
        List<PackageInfo> apps = pm.getInstalledPackages(PackageManager.GET_SIGNATURES); 
        Iterator<PackageInfo> iter = apps.iterator(); 
        while(iter.hasNext()) { 
             PackageInfo packageinfo = iter.next(); 
                return packageinfo.signatures[0].toCharsString(); 
     } 
        return null; 
    }

而得到的信息是样子的：

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

那么，我如何才能进行比对呢？

我对用Keytool获取到的签名信息的MD5指纹是怎么生成的并不了解，有些地方理解或许会有错误，请大神们不吝指教！

Answer 1

The questioner is actually one step away from the goal. The questioner encrypts the obtained strings with MD5 or SHA1. The encrypted value obtained is the value that the questioner uses for comparison and verification (corresponding to MD5 and SHA1 respectively. SHA1), MD5 and SHA1 encryption methods. I believe that the subject should be able to find the writing method by himself.