如何验证系统上的其他应用程序是否为正版？

Question

我想将包含敏感信息的意图发送到系统上的另一个应用程序,我也写过.在此之前,我需要验证我发送给他们的应用程序是否由我签名,而不仅仅是具有相同包名和类的流氓版本.我该如何以编程方式执行此操作？

我想使用通过startService()和startActivity()调度的显式意图来做到这一点,因此不存在广播意图的问题.也就是说,在我确认我指定的软件包名称是由作者安装和签名之前,我不想发送任何内容(我自己在这种特定情况下).

Answer 1

包管理器将为您提供任何已安装包的签名证书。

final PackageManager packageManager = context.getPackageManager();
final List<PackageInfo> packageList = packageManager.getInstalledPackages(PackageManager.GET_SIGNATURES);
CertificateFactory certFactory = null;
try {
    certFactory = CertificateFactory.getInstance("X509");
}
catch (CertificateException e) {
    // e.printStackTrace();
}

for (PackageInfo p : packageList) {
    String strName = p.applicationInfo.loadLabel(packageManager).toString();
    String strVendor = p.packageName;

    sb.append("<br>" + strName + " / " + strVendor + "<br>");

    Signature[] arrSignatures = p.signatures;
    for (Signature sig : arrSignatures) {
        /*
        * Get the X.509 certificate.
        */
        byte[] rawCert = sig.toByteArray();
        InputStream certStream = new ByteArrayInputStream(rawCert);

        X509Certificate x509Cert = null;
        try {
            x509Cert = (X509Certificate) certFactory.generateCertificate(certStream);
        }
        catch (CertificateException e) {
            // e.printStackTrace();
        }

        sb.append("Certificate subject: " + x509Cert.getSubjectDN() + "<br>");
        sb.append("Certificate issuer: " + x509Cert.getIssuerDN() + "<br>");
        sb.append("Certificate serial number: " + x509Cert.getSerialNumber() + "<br>");
        sb.append("<br>");
    }
}