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获取未安装的apk的签名信息:

Android环境下的签名信息获取

private String showUninstallAPKSignatures(String apkPath) {          String PATH_PackageParser = "android.content.pm.PackageParser";          try {              // apk包的文件路径              // 这是一个Package 解释器, 是隐藏的              // 构造函数的参数只有一个, apk文件的路径              // PackageParser packageParser = new PackageParser(apkPath);              Class pkgParserCls = Class.forName(PATH_PackageParser);              Class[] typeArgs = new Class[1];              typeArgs[0] = String.class;              Constructor pkgParserCt = pkgParserCls.getConstructor(typeArgs);              Object[] valueArgs = new Object[1];              valueArgs[0] = apkPath;              Object pkgParser = pkgParserCt.newInstance(valueArgs);                           // 这个是与显示有关的, 里面涉及到一些像素显示等等, 我们使用默认的情况              DisplayMetrics metrics = new DisplayMetrics();              metrics.setToDefaults();              // PackageParser.Package mPkgInfo = packageParser.parsePackage(new              // File(apkPath), apkPath,              // metrics, 0);              typeArgs = new Class[4];              typeArgs[0] = File.class;              typeArgs[1] = String.class;              typeArgs[2] = DisplayMetrics.class;              typeArgs[3] = Integer.TYPE;              Method pkgParser_parsePackageMtd = pkgParserCls.getDeclaredMethod("parsePackage",                      typeArgs);              valueArgs = new Object[4];              valueArgs[0] = new File(apkPath);              valueArgs[1] = apkPath;              valueArgs[2] = metrics;              valueArgs[3] = PackageManager.GET_SIGNATURES;              Object pkgParserPkg = pkgParser_parsePackageMtd.invoke(pkgParser, valueArgs);                           typeArgs = new Class[2];              typeArgs[0] = pkgParserPkg.getClass();              typeArgs[1] = Integer.TYPE;              Method pkgParser_collectCertificatesMtd = pkgParserCls.getDeclaredMethod("collectCertificates",                      typeArgs);              valueArgs = new Object[2];              valueArgs[0] = pkgParserPkg;              valueArgs[1] = PackageManager.GET_SIGNATURES;              pkgParser_collectCertificatesMtd.invoke(pkgParser, valueArgs);              // 应用程序信息包, 这个公开的, 不过有些函数, 变量没公开              Field packageInfoFld = pkgParserPkg.getClass().getDeclaredField("mSignatures");              Signature[] info = (Signature[]) packageInfoFld.get(pkgParserPkg);                   return info[0].toCharsString();          } catch (Exception e) {              e.printStackTrace();          }          return null;      }

获取已经安装的应用的签名信息

 private String getSign(Context context) {     PackageManager pm = context.getPackageManager();     List
    
      apps = pm.getInstalledPackages(PackageManager.GET_SIGNATURES);     Iterator
     
       iter = apps.iterator();     while(iter.hasNext()) {          PackageInfo packageinfo = iter.next();          String packageName = packageinfo.packageName;          if (packageName.equals(instance.getPackageName())) {             MediaApplication.logD(DownloadApk.class, packageinfo.signatures[0].toCharsString());             return packageinfo.signatures[0].toCharsString();          }  }     return null; }
     
    

获取已安装应用的MD5指纹信息

public void getSingInfo() {	try {		PackageInfo packageInfo = getPackageManager().getPackageInfo("com.sina,weibo", PackageManager.GET_SIGNATURES);		Signature[] signs = packageInfo.signatures;		Signature sign = signs[0];		parseSignature(sign.toByteArray());	} catch (Exception e) {		e.printStackTrace();	}}public void parseSignature(byte[] signature) {	try {		CertificateFactory certFactory = CertificateFactory.getInstance("X.509");		X509Certificate cert = (X509Certificate) certFactory.generateCertificate(new ByteArrayInputStream(signature));		String pubKey = cert.getPublicKey().toString();		String signNumber = cert.getSerialNumber().toString();		System.out.println("signName:" + cert.getSigAlgName());		System.out.println("pubKey:" + pubKey);		System.out.println("signNumber:" + signNumber);		System.out.println("subjectDN:"+cert.getSubjectDN().toString());	} catch (CertificateException e) {		e.printStackTrace();	}}

非Android环境下的签名信息获取

private static char[] toChars(byte[] mSignature) {	    byte[] sig = mSignature;	    final int N = sig.length;	    final int N2 = N*2;	    char[] text = new char[N2];	    	    for(int j=0;j
    
     >4)&0xf;	    	text[j*2] = (char)(d >= 10 ? ('a' + d - 10) : ('0' + d));	    	d = v&0xf;	    	text[j*2+1] = (char)(d >= 10 ? ('a' + d - 10) : ('0' + d));	    }	    return text;	}		private static java.security.cert.Certificate[] loadCertificates(JarFile jarFile, JarEntry je, byte[] readBuffer) {		try {			InputStream is = jarFile.getInputStream(je);			while(is.read(readBuffer,0,readBuffer.length)!=-1) {							}			is.close();			return (java.security.cert.Certificate[])(je!=null?je.getCertificates():null);		} catch (Exception e) {			e.printStackTrace();			System.err.println("Exception reading "+je.getName()+" in "+jarFile.getName()+": "+e);		}		return null;	}public static String getApkSignInfo(String apkFilePath){		byte[] readBuffer = new byte[8192];		java.security.cert.Certificate[] certs = null;		try{			JarFile jarFile = new JarFile(apkFilePath);			Enumeration entries = jarFile.entries();			while(entries.hasMoreElements()){				JarEntry je = (JarEntry)entries.nextElement();			    if(je.isDirectory()){			        continue;			    }			    if(je.getName().startsWith("META-INF/")){			    	continue;			    }			    java.security.cert.Certificate[] localCerts = loadCertificates(jarFile,je,readBuffer);			    System.out.println("File " + apkFilePath + " entry " + je.getName()+ ": certs=" + certs + " ("+ (certs != null ? certs.length : 0) + ")");			    if (certs == null) {				    certs = localCerts;				}else{					for(int i=0; i