我正在从事一个分析 APK 文件以检测恶意软件应用程序的项目，我想知道如何提取签名时间而不是打包时间。这是我从一篇论文中读到的一项功能，它似乎非常有用。
请您参考如下方法:
据我所知，至少有三种方法可以获得签约时间之类的信息。首先是使用keytool:
$ keytool -printcert -jarfile sample.apk
Signer #1:
Signature:
Owner: CN=GService inc, OU=G Service inc, O=G, L=New York, ST=New York, C=US
Issuer: CN=GService inc, OU=G Service inc, O=G, L=New York, ST=New York, C=US
Serial number: 6f30f864
Valid from: Thu Dec 17 04:12:27 PST 2015 until: Wed Dec 12 04:12:27 PST 2035
Certificate fingerprints:
MD5: 4D:36:65:14:59:5B:74:8F:2C:9D:92:30:F6:1D:90:8A
SHA1: A8:85:7B:72:4C:EE:55:83:09:D5:AC:5D:1A:02:80:C5:F6:83:2B:40
SHA256: 04:A7:24:9F:35:D5:8D:7E:F6:0F:73:81:35:5D:23:16:0D:FC:EA:61:C4:15:61:CC:06:8D:36:D9:C6:55:12:B7
Signature algorithm name: SHA256withRSA
Version: 3
Extensions:
#1: ObjectId: 2.5.29.14 Criticality=false
SubjectKeyIdentifier [
KeyIdentifier [
0000: C1 C5 19 32 72 47 46 C5 01 CC 4B AF 12 40 3D D2 ...2rGF...K..@=.
0010: B5 52 45 5E .RE^
]
]
这会为您提供证书创建的可能时间:Thu Dec 17 04:12:27 PST 2015。
第二种是使用jarsigner:
$ jarsigner -verify -verbose sample.apk
sm 4284 Wed Apr 13 11:03:18 PDT 2016 AndroidManifest.xml
sm 9193 Wed Apr 13 11:03:18 PDT 2016 res/drawable-hdpi-v4/ic_launcher.png
sm 5057 Wed Apr 13 11:03:18 PDT 2016 res/drawable-mdpi-v4/ic_launcher.png
sm 14068 Wed Apr 13 11:03:18 PDT 2016 res/drawable-xhdpi-v4/ic_launcher.png
sm 1408 Wed Apr 13 11:03:18 PDT 2016 resources.arsc
sm 20388 Wed Apr 13 11:03:18 PDT 2016 classes.dex
s 523 Wed Apr 13 11:03:18 PDT 2016 META-INF/MANIFEST.MF
576 Wed Apr 13 11:03:18 PDT 2016 META-INF/CERT.SF
1368 Wed Apr 13 11:03:18 PDT 2016 META-INF/CERT.RSA
s = signature was verified
m = entry is listed in manifest
k = at least one certificate was found in keystore
i = at least one certificate was found in identity scope
这会为您提供 APK 中所有条目的最后修改时间。它们在这个 APK 中都是一样的，但有时会有所不同。所有最后修改时间可能必须大于“有效起始”日期。
第三个选项是在 Java 中以编程方式使用 JarFile:
private static void printCertInfo(String jarPath) throws Exception {
// verify = true is key here
JarFile apkFile = new JarFile(jarPath, true);
JarEntry androidManifestEntry = apkFile.getJarEntry("AndroidManifest.xml");
if (androidManifestEntry == null) {
System.err.println("APK has no AndroidManifest.xml");
System.exit(-1);
}
// Need to fully read stream to verify cert
System.out.println("Android manifest probably signed: " + androidManifestEntry.getLastModifiedTime());
ByteStreams.copy(apkFile.getInputStream(androidManifestEntry), ByteStreams.nullOutputStream());
// Assuming only signed with a single cert (not always true, but you get the idea)
X509Certificate cert = (X509Certificate) androidManifestEntry.getCertificates()[0];
System.out.println("Android manifest cert probably created: " + cert.getNotBefore());
System.out.println("Full cert: " + cert.toString());
}
您可能认为您可以使用 androidManifestEntry.getCodeSigners()[0].getTimestamp() 但它始终为 null 而我不确定它是什么。上面的代码给出了这个输出:
Android manifest probably signed: 2016-04-13T18:03:18Z
Android manifest cert probably created: Thu Dec 17 04:12:27 PST 2015
Full cert: [
[
Version: V3
Subject: CN=GService inc, OU=G Service inc, O=G, L=New York, ST=New York, C=US
Signature Algorithm: SHA256withRSA, OID = 1.2.840.113549.1.1.11
// ** SNIP -- you get the idea **
