1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
|
/*
* Copyright (C) 2014 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.android.verity;
import java.io.IOException;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.Security;
import java.security.Signature;
import java.security.cert.X509Certificate;
import java.util.Enumeration;
import org.bouncycastle.asn1.ASN1Encodable;
import org.bouncycastle.asn1.ASN1EncodableVector;
import org.bouncycastle.asn1.ASN1InputStream;
import org.bouncycastle.asn1.ASN1Integer;
import org.bouncycastle.asn1.ASN1Object;
import org.bouncycastle.asn1.ASN1Primitive;
import org.bouncycastle.asn1.ASN1Sequence;
import org.bouncycastle.asn1.DEROctetString;
import org.bouncycastle.asn1.DERPrintableString;
import org.bouncycastle.asn1.DERSequence;
import org.bouncycastle.asn1.pkcs.PKCSObjectIdentifiers;
import org.bouncycastle.asn1.pkcs.RSAPublicKey;
import org.bouncycastle.asn1.util.ASN1Dump;
import org.bouncycastle.asn1.x509.AlgorithmIdentifier;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
/**
* AndroidVerifiedBootKeystore DEFINITIONS ::=
* BEGIN
* FormatVersion ::= INTEGER
* KeyBag ::= SEQUENCE {
* Key ::= SEQUENCE {
* AlgorithmIdentifier ::= SEQUENCE {
* algorithm OBJECT IDENTIFIER,
* parameters ANY DEFINED BY algorithm OPTIONAL
* }
* KeyMaterial ::= RSAPublicKey
* }
* }
* Signature ::= AndroidVerifiedBootSignature
* END
*/
class BootKey extends ASN1Object
{
private AlgorithmIdentifier algorithmIdentifier;
private RSAPublicKey keyMaterial;
public BootKey(PublicKey key) throws Exception {
java.security.interfaces.RSAPublicKey k =
(java.security.interfaces.RSAPublicKey) key;
this.keyMaterial = new RSAPublicKey(
k.getModulus(),
k.getPublicExponent());
this.algorithmIdentifier = Utils.getSignatureAlgorithmIdentifier(key);
}
public ASN1Primitive toASN1Primitive() {
ASN1EncodableVector v = new ASN1EncodableVector();
v.add(algorithmIdentifier);
v.add(keyMaterial);
return new DERSequence(v);
}
public void dump() throws Exception {
System.out.println(ASN1Dump.dumpAsString(toASN1Primitive()));
}
}
class BootKeystore extends ASN1Object
{
private ASN1Integer formatVersion;
private ASN1EncodableVector keyBag;
private BootSignature signature;
private X509Certificate certificate;
private static final int FORMAT_VERSION = 0;
public BootKeystore() {
this.formatVersion = new ASN1Integer(FORMAT_VERSION);
this.keyBag = new ASN1EncodableVector();
}
public void addPublicKey(byte[] der) throws Exception {
PublicKey pubkey = Utils.loadDERPublicKey(der);
BootKey k = new BootKey(pubkey);
keyBag.add(k);
}
public void setCertificate(X509Certificate cert) {
certificate = cert;
}
public byte[] getInnerKeystore() throws Exception {
ASN1EncodableVector v = new ASN1EncodableVector();
v.add(formatVersion);
v.add(new DERSequence(keyBag));
return new DERSequence(v).getEncoded();
}
public ASN1Primitive toASN1Primitive() {
ASN1EncodableVector v = new ASN1EncodableVector();
v.add(formatVersion);
v.add(new DERSequence(keyBag));
v.add(signature);
return new DERSequence(v);
}
public void parse(byte[] input) throws Exception {
ASN1InputStream stream = new ASN1InputStream(input);
ASN1Sequence sequence = (ASN1Sequence) stream.readObject();
formatVersion = (ASN1Integer) sequence.getObjectAt(0);
if (formatVersion.getValue().intValue() != FORMAT_VERSION) {
throw new IllegalArgumentException("Unsupported format version");
}
ASN1Sequence keys = (ASN1Sequence) sequence.getObjectAt(1);
Enumeration e = keys.getObjects();
while (e.hasMoreElements()) {
keyBag.add((ASN1Encodable) e.nextElement());
}
ASN1Object sig = sequence.getObjectAt(2).toASN1Primitive();
signature = new BootSignature(sig.getEncoded());
}
public boolean verify() throws Exception {
byte[] innerKeystore = getInnerKeystore();
return Utils.verify(signature.getPublicKey(), innerKeystore,
signature.getSignature(), signature.getAlgorithmIdentifier());
}
public void sign(PrivateKey privateKey) throws Exception {
byte[] innerKeystore = getInnerKeystore();
byte[] rawSignature = Utils.sign(privateKey, innerKeystore);
signature = new BootSignature("keystore", innerKeystore.length);
signature.setCertificate(certificate);
signature.setSignature(rawSignature,
Utils.getSignatureAlgorithmIdentifier(privateKey));
}
public void dump() throws Exception {
System.out.println(ASN1Dump.dumpAsString(toASN1Primitive()));
}
private static void usage() {
System.err.println("usage: KeystoreSigner <privatekey.pk8> " +
"<certificate.x509.pem> <outfile> <publickey0.der> " +
"... <publickeyN-1.der> | -verify <keystore>");
System.exit(1);
}
public static void main(String[] args) throws Exception {
if (args.length < 2) {
usage();
return;
}
Security.addProvider(new BouncyCastleProvider());
BootKeystore ks = new BootKeystore();
if ("-verify".equals(args[0])) {
ks.parse(Utils.read(args[1]));
try {
if (ks.verify()) {
System.err.println("Signature is VALID");
System.exit(0);
} else {
System.err.println("Signature is INVALID");
}
} catch (Exception e) {
e.printStackTrace(System.err);
}
System.exit(1);
} else {
String privkeyFname = args[0];
String certFname = args[1];
String outfileFname = args[2];
ks.setCertificate(Utils.loadPEMCertificate(certFname));
for (int i = 3; i < args.length; i++) {
ks.addPublicKey(Utils.read(args[i]));
}
ks.sign(Utils.loadDERPrivateKeyFromFile(privkeyFname));
Utils.write(ks.getEncoded(), outfileFname);
}
}
}
|
