1 /* 2 * Copyright (C) 2013 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.android.settings.vpn2; 18 19 import android.os.Environment; 20 import android.security.Credentials; 21 import android.security.KeyStore; 22 import android.util.Log; 23 24 import com.android.internal.net.VpnProfile; 25 import com.android.org.bouncycastle.asn1.ASN1InputStream; 26 import com.android.org.bouncycastle.asn1.ASN1Sequence; 27 import com.android.org.bouncycastle.asn1.DEROctetString; 28 import com.android.org.bouncycastle.asn1.x509.BasicConstraints; 29 30 import junit.framework.Assert; 31 32 import libcore.io.Streams; 33 34 import java.io.ByteArrayInputStream; 35 import java.io.File; 36 import java.io.FileInputStream; 37 import java.io.IOException; 38 import java.io.InputStream; 39 import java.nio.charset.StandardCharsets; 40 import java.security.KeyStoreException; 41 import java.security.NoSuchAlgorithmException; 42 import java.security.KeyStore.PasswordProtection; 43 import java.security.KeyStore.PrivateKeyEntry; 44 import java.security.PrivateKey; 45 import java.security.UnrecoverableEntryException; 46 import java.security.cert.Certificate; 47 import java.security.cert.CertificateEncodingException; 48 import java.security.cert.CertificateException; 49 import java.security.cert.X509Certificate; 50 import java.util.ArrayList; 51 import java.util.Collections; 52 import java.util.Enumeration; 53 import java.util.List; 54 55 /** 56 * Certificate installer helper to extract information from a provided file 57 * and install certificates to keystore. 58 */ 59 public class CertInstallerHelper { 60 private static final String TAG = "CertInstallerHelper"; 61 /* Define a password to unlock keystore after it is reset */ 62 private static final String CERT_STORE_PASSWORD = "password"; 63 private final int mUid = KeyStore.UID_SELF; 64 private PrivateKey mUserKey; // private key 65 private X509Certificate mUserCert; // user certificate 66 private List<X509Certificate> mCaCerts = new ArrayList<X509Certificate>(); 67 private KeyStore mKeyStore = KeyStore.getInstance(); 68 69 /** 70 * Unlock keystore and set password 71 */ CertInstallerHelper()72 public CertInstallerHelper() { 73 mKeyStore.reset(); 74 mKeyStore.onUserPasswordChanged(CERT_STORE_PASSWORD); 75 } 76 extractCertificate(String certFile, String password)77 private void extractCertificate(String certFile, String password) { 78 InputStream in = null; 79 final byte[] raw; 80 java.security.KeyStore keystore = null; 81 try { 82 // Read .p12 file from SDCARD and extract with password 83 in = new FileInputStream(new File( 84 Environment.getExternalStorageDirectory(), certFile)); 85 raw = Streams.readFully(in); 86 87 keystore = java.security.KeyStore.getInstance("PKCS12"); 88 PasswordProtection passwordProtection = new PasswordProtection(password.toCharArray()); 89 keystore.load(new ByteArrayInputStream(raw), passwordProtection.getPassword()); 90 91 // Install certificates and private keys 92 Enumeration<String> aliases = keystore.aliases(); 93 if (!aliases.hasMoreElements()) { 94 Assert.fail("key store failed to put in keychain"); 95 } 96 ArrayList<String> aliasesList = Collections.list(aliases); 97 // The keystore is initialized for each test case, there will 98 // be only one alias in the keystore 99 Assert.assertEquals(1, aliasesList.size()); 100 String alias = aliasesList.get(0); 101 java.security.KeyStore.Entry entry = keystore.getEntry(alias, passwordProtection); 102 Log.d(TAG, "extracted alias = " + alias + ", entry=" + entry.getClass()); 103 104 if (entry instanceof PrivateKeyEntry) { 105 Assert.assertTrue(installFrom((PrivateKeyEntry) entry)); 106 } 107 } catch (IOException e) { 108 Assert.fail("Failed to read certficate: " + e); 109 } catch (KeyStoreException e) { 110 Log.e(TAG, "failed to extract certificate" + e); 111 } catch (NoSuchAlgorithmException e) { 112 Log.e(TAG, "failed to extract certificate" + e); 113 } catch (CertificateException e) { 114 Log.e(TAG, "failed to extract certificate" + e); 115 } catch (UnrecoverableEntryException e) { 116 Log.e(TAG, "failed to extract certificate" + e); 117 } 118 finally { 119 if (in != null) { 120 try { 121 in.close(); 122 } catch (IOException e) { 123 Log.e(TAG, "close FileInputStream error: " + e); 124 } 125 } 126 } 127 } 128 129 /** 130 * Extract private keys, user certificates and ca certificates 131 */ installFrom(PrivateKeyEntry entry)132 private synchronized boolean installFrom(PrivateKeyEntry entry) { 133 mUserKey = entry.getPrivateKey(); 134 mUserCert = (X509Certificate) entry.getCertificate(); 135 136 Certificate[] certs = entry.getCertificateChain(); 137 Log.d(TAG, "# certs extracted = " + certs.length); 138 mCaCerts = new ArrayList<X509Certificate>(certs.length); 139 for (Certificate c : certs) { 140 X509Certificate cert = (X509Certificate) c; 141 if (isCa(cert)) { 142 mCaCerts.add(cert); 143 } 144 } 145 Log.d(TAG, "# ca certs extracted = " + mCaCerts.size()); 146 return true; 147 } 148 isCa(X509Certificate cert)149 private boolean isCa(X509Certificate cert) { 150 try { 151 byte[] asn1EncodedBytes = cert.getExtensionValue("2.5.29.19"); 152 if (asn1EncodedBytes == null) { 153 return false; 154 } 155 DEROctetString derOctetString = (DEROctetString) 156 new ASN1InputStream(asn1EncodedBytes).readObject(); 157 byte[] octets = derOctetString.getOctets(); 158 ASN1Sequence sequence = (ASN1Sequence) 159 new ASN1InputStream(octets).readObject(); 160 return BasicConstraints.getInstance(sequence).isCA(); 161 } catch (IOException e) { 162 return false; 163 } 164 } 165 166 /** 167 * Extract certificate from the given file, and install it to keystore 168 * @param name certificate name 169 * @param certFile .p12 file which includes certificates 170 * @param password password to extract the .p12 file 171 */ installCertificate(VpnProfile profile, String certFile, String password)172 public void installCertificate(VpnProfile profile, String certFile, String password) { 173 // extract private keys, certificates from the provided file 174 extractCertificate(certFile, password); 175 // install certificate to the keystore 176 int flags = KeyStore.FLAG_ENCRYPTED; 177 try { 178 if (mUserKey != null) { 179 Log.v(TAG, "has private key"); 180 String key = Credentials.USER_PRIVATE_KEY + profile.ipsecUserCert; 181 byte[] value = mUserKey.getEncoded(); 182 183 if (!mKeyStore.importKey(key, value, mUid, flags)) { 184 Log.e(TAG, "Failed to install " + key + " as user " + mUid); 185 return; 186 } 187 Log.v(TAG, "install " + key + " as user " + mUid + " is successful"); 188 } 189 190 if (mUserCert != null) { 191 String certName = Credentials.USER_CERTIFICATE + profile.ipsecUserCert; 192 byte[] certData = Credentials.convertToPem(mUserCert); 193 194 if (!mKeyStore.put(certName, certData, mUid, flags)) { 195 Log.e(TAG, "Failed to install " + certName + " as user " + mUid); 196 return; 197 } 198 Log.v(TAG, "install " + certName + " as user" + mUid + " is successful."); 199 } 200 201 if (!mCaCerts.isEmpty()) { 202 String caListName = Credentials.CA_CERTIFICATE + profile.ipsecCaCert; 203 X509Certificate[] caCerts = mCaCerts.toArray(new X509Certificate[mCaCerts.size()]); 204 byte[] caListData = Credentials.convertToPem(caCerts); 205 206 if (!mKeyStore.put(caListName, caListData, mUid, flags)) { 207 Log.e(TAG, "Failed to install " + caListName + " as user " + mUid); 208 return; 209 } 210 Log.v(TAG, " install " + caListName + " as user " + mUid + " is successful"); 211 } 212 } catch (CertificateEncodingException e) { 213 Log.e(TAG, "Exception while convert certificates to pem " + e); 214 throw new AssertionError(e); 215 } catch (IOException e) { 216 Log.e(TAG, "IOException while convert to pem: " + e); 217 } 218 } 219 getUid()220 public int getUid() { 221 return mUid; 222 } 223 } 224