1 //
2 // Copyright (C) 2010 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 #include "update_engine/payload_generator/payload_signer.h"
18 
19 #include <string>
20 #include <vector>
21 
22 #include <base/logging.h>
23 #include <gtest/gtest.h>
24 
25 #include "update_engine/common/hash_calculator.h"
26 #include "update_engine/common/utils.h"
27 #include "update_engine/payload_consumer/payload_constants.h"
28 #include "update_engine/payload_consumer/payload_verifier.h"
29 #include "update_engine/payload_generator/payload_file.h"
30 #include "update_engine/update_metadata.pb.h"
31 
32 using std::string;
33 using std::vector;
34 
35 // Note: the test key was generated with the following command:
36 // openssl genrsa -out unittest_key.pem 2048
37 // The public-key version is created by the build system.
38 
39 namespace chromeos_update_engine {
40 
41 const char* kUnittestPrivateKeyPath = "unittest_key.pem";
42 const char* kUnittestPublicKeyPath = "unittest_key.pub.pem";
43 const char* kUnittestPrivateKey2Path = "unittest_key2.pem";
44 const char* kUnittestPublicKey2Path = "unittest_key2.pub.pem";
45 
46 // Some data and its corresponding hash and signature:
47 const char kDataToSign[] = "This is some data to sign.";
48 
49 // Generated by:
50 // echo -n 'This is some data to sign.' | openssl dgst -sha256 -binary |
51 //   hexdump -v -e '" " 8/1 "0x%02x, " "\n"'
52 const uint8_t kDataHash[] = {
53   0x7a, 0x07, 0xa6, 0x44, 0x08, 0x86, 0x20, 0xa6,
54   0xc1, 0xf8, 0xd9, 0x02, 0x05, 0x63, 0x0d, 0xb7,
55   0xfc, 0x2b, 0xa0, 0xa9, 0x7c, 0x9d, 0x1d, 0x8c,
56   0x01, 0xf5, 0x78, 0x6d, 0xc5, 0x11, 0xb4, 0x06
57 };
58 
59 // Generated with openssl 1.0, which at the time of this writing, you need
60 // to download and install yourself. Here's my command:
61 // echo -n 'This is some data to sign.' | openssl dgst -sha256 -binary |
62 //    ~/local/bin/openssl pkeyutl -sign -inkey unittest_key.pem -pkeyopt
63 //    digest:sha256 | hexdump -v -e '" " 8/1 "0x%02x, " "\n"'
64 const uint8_t kDataSignature[] = {
65   0x9f, 0x86, 0x25, 0x8b, 0xf3, 0xcc, 0xe3, 0x95,
66   0x5f, 0x45, 0x83, 0xb2, 0x66, 0xf0, 0x2a, 0xcf,
67   0xb7, 0xaa, 0x52, 0x25, 0x7a, 0xdd, 0x9d, 0x65,
68   0xe5, 0xd6, 0x02, 0x4b, 0x37, 0x99, 0x53, 0x06,
69   0xc2, 0xc9, 0x37, 0x36, 0x25, 0x62, 0x09, 0x4f,
70   0x6b, 0x22, 0xf8, 0xb3, 0x89, 0x14, 0x98, 0x1a,
71   0xbc, 0x30, 0x90, 0x4a, 0x43, 0xf5, 0xea, 0x2e,
72   0xf0, 0xa4, 0xba, 0xc3, 0xa7, 0xa3, 0x44, 0x70,
73   0xd6, 0xc4, 0x89, 0xd8, 0x45, 0x71, 0xbb, 0xee,
74   0x59, 0x87, 0x3d, 0xd5, 0xe5, 0x40, 0x22, 0x3d,
75   0x73, 0x7e, 0x2a, 0x58, 0x93, 0x8e, 0xcb, 0x9c,
76   0xf2, 0xbb, 0x4a, 0xc9, 0xd2, 0x2c, 0x52, 0x42,
77   0xb0, 0xd1, 0x13, 0x22, 0xa4, 0x78, 0xc7, 0xc6,
78   0x3e, 0xf1, 0xdc, 0x4c, 0x7b, 0x2d, 0x40, 0xda,
79   0x58, 0xac, 0x4a, 0x11, 0x96, 0x3d, 0xa0, 0x01,
80   0xf6, 0x96, 0x74, 0xf6, 0x6c, 0x0c, 0x49, 0x69,
81   0x4e, 0xc1, 0x7e, 0x9f, 0x2a, 0x42, 0xdd, 0x15,
82   0x6b, 0x37, 0x2e, 0x3a, 0xa7, 0xa7, 0x6d, 0x91,
83   0x13, 0xe8, 0x59, 0xde, 0xfe, 0x99, 0x07, 0xd9,
84   0x34, 0x0f, 0x17, 0xb3, 0x05, 0x4c, 0xd2, 0xc6,
85   0x82, 0xb7, 0x38, 0x36, 0x63, 0x1d, 0x9e, 0x21,
86   0xa6, 0x32, 0xef, 0xf1, 0x65, 0xe6, 0xed, 0x95,
87   0x25, 0x9b, 0x61, 0xe0, 0xba, 0x86, 0xa1, 0x7f,
88   0xf8, 0xa5, 0x4a, 0x32, 0x1f, 0x15, 0x20, 0x8a,
89   0x41, 0xc5, 0xb0, 0xd9, 0x4a, 0xda, 0x85, 0xf3,
90   0xdc, 0xa0, 0x98, 0x5d, 0x1d, 0x18, 0x9d, 0x2e,
91   0x42, 0xea, 0x69, 0x13, 0x74, 0x3c, 0x74, 0xf7,
92   0x6d, 0x43, 0xb0, 0x63, 0x90, 0xdb, 0x04, 0xd5,
93   0x05, 0xc9, 0x73, 0x1f, 0x6c, 0xd6, 0xfa, 0x46,
94   0x4e, 0x0f, 0x33, 0x58, 0x5b, 0x0d, 0x1b, 0x55,
95   0x39, 0xb9, 0x0f, 0x43, 0x37, 0xc0, 0x06, 0x0c,
96   0x29, 0x93, 0x43, 0xc7, 0x43, 0xb9, 0xab, 0x7d
97 };
98 
99 namespace {
SignSampleData(brillo::Blob * out_signature_blob,const vector<string> & private_keys)100 void SignSampleData(brillo::Blob* out_signature_blob,
101                     const vector<string>& private_keys) {
102   brillo::Blob data_blob(std::begin(kDataToSign),
103                          std::begin(kDataToSign) + strlen(kDataToSign));
104   uint64_t length = 0;
105   EXPECT_TRUE(PayloadSigner::SignatureBlobLength(private_keys, &length));
106   EXPECT_GT(length, 0U);
107   brillo::Blob hash_blob;
108   EXPECT_TRUE(HashCalculator::RawHashOfBytes(data_blob.data(),
109                                              data_blob.size(),
110                                              &hash_blob));
111   EXPECT_TRUE(PayloadSigner::SignHashWithKeys(
112       hash_blob,
113       private_keys,
114       out_signature_blob));
115   EXPECT_EQ(length, out_signature_blob->size());
116 }
117 }  // namespace
118 
119 class PayloadSignerTest : public ::testing::Test {
120  protected:
SetUp()121   void SetUp() override {
122     PayloadVerifier::PadRSA2048SHA256Hash(&padded_hash_data_);
123   }
124 
DoWriteAndLoadPayloadTest(const PayloadGenerationConfig & config)125   void DoWriteAndLoadPayloadTest(const PayloadGenerationConfig& config) {
126     PayloadFile payload;
127     payload.Init(config);
128     string payload_path;
129     EXPECT_TRUE(utils::MakeTempFile("payload.XXXXXX", &payload_path, nullptr));
130     ScopedPathUnlinker payload_path_unlinker(payload_path);
131     uint64_t metadata_size;
132     EXPECT_TRUE(
133         payload.WritePayload(payload_path, "/dev/null", "", &metadata_size));
134     brillo::Blob payload_metadata_blob;
135     DeltaArchiveManifest manifest;
136     uint64_t load_metadata_size, load_major_version;
137     EXPECT_TRUE(PayloadSigner::LoadPayloadMetadata(payload_path,
138                                                    &payload_metadata_blob,
139                                                    &manifest,
140                                                    &load_major_version,
141                                                    &load_metadata_size,
142                                                    nullptr));
143     EXPECT_EQ(metadata_size, payload_metadata_blob.size());
144     EXPECT_EQ(config.version.major, load_major_version);
145     EXPECT_EQ(metadata_size, load_metadata_size);
146   }
147 
148   brillo::Blob padded_hash_data_{std::begin(kDataHash), std::end(kDataHash)};
149 };
150 
TEST_F(PayloadSignerTest,LoadPayloadV1Test)151 TEST_F(PayloadSignerTest, LoadPayloadV1Test) {
152   PayloadGenerationConfig config;
153   config.version.major = kChromeOSMajorPayloadVersion;
154   DoWriteAndLoadPayloadTest(config);
155 }
156 
TEST_F(PayloadSignerTest,LoadPayloadV2Test)157 TEST_F(PayloadSignerTest, LoadPayloadV2Test) {
158   PayloadGenerationConfig config;
159   config.version.major = kBrilloMajorPayloadVersion;
160   DoWriteAndLoadPayloadTest(config);
161 }
162 
TEST_F(PayloadSignerTest,SignSimpleTextTest)163 TEST_F(PayloadSignerTest, SignSimpleTextTest) {
164   brillo::Blob signature_blob;
165   SignSampleData(&signature_blob, {kUnittestPrivateKeyPath});
166 
167   // Check the signature itself
168   Signatures signatures;
169   EXPECT_TRUE(signatures.ParseFromArray(signature_blob.data(),
170                                         signature_blob.size()));
171   EXPECT_EQ(1, signatures.signatures_size());
172   const Signatures_Signature& signature = signatures.signatures(0);
173   EXPECT_EQ(1U, signature.version());
174   const string sig_data = signature.data();
175   ASSERT_EQ(arraysize(kDataSignature), sig_data.size());
176   for (size_t i = 0; i < arraysize(kDataSignature); i++) {
177     EXPECT_EQ(kDataSignature[i], static_cast<uint8_t>(sig_data[i]));
178   }
179 }
180 
TEST_F(PayloadSignerTest,VerifyAllSignatureTest)181 TEST_F(PayloadSignerTest, VerifyAllSignatureTest) {
182   brillo::Blob signature_blob;
183   SignSampleData(&signature_blob,
184                  {kUnittestPrivateKeyPath, kUnittestPrivateKey2Path});
185 
186   // Either public key should pass the verification.
187   EXPECT_TRUE(PayloadVerifier::VerifySignature(signature_blob,
188                                                kUnittestPublicKeyPath,
189                                                padded_hash_data_));
190   EXPECT_TRUE(PayloadVerifier::VerifySignature(signature_blob,
191                                                kUnittestPublicKey2Path,
192                                                padded_hash_data_));
193 }
194 
TEST_F(PayloadSignerTest,VerifySignatureTest)195 TEST_F(PayloadSignerTest, VerifySignatureTest) {
196   brillo::Blob signature_blob;
197   SignSampleData(&signature_blob, {kUnittestPrivateKeyPath});
198 
199   EXPECT_TRUE(PayloadVerifier::VerifySignature(signature_blob,
200                                                kUnittestPublicKeyPath,
201                                                padded_hash_data_));
202   // Passing the invalid key should fail the verification.
203   EXPECT_FALSE(PayloadVerifier::VerifySignature(signature_blob,
204                                                 kUnittestPublicKey2Path,
205                                                 padded_hash_data_));
206 }
207 
TEST_F(PayloadSignerTest,SkipMetadataSignatureTest)208 TEST_F(PayloadSignerTest, SkipMetadataSignatureTest) {
209   string payload_path;
210   EXPECT_TRUE(utils::MakeTempFile("payload.XXXXXX", &payload_path, nullptr));
211   ScopedPathUnlinker payload_path_unlinker(payload_path);
212 
213   PayloadGenerationConfig config;
214   config.version.major = kBrilloMajorPayloadVersion;
215   PayloadFile payload;
216   EXPECT_TRUE(payload.Init(config));
217   uint64_t metadata_size;
218   EXPECT_TRUE(
219       payload.WritePayload(payload_path, "/dev/null", "", &metadata_size));
220   const vector<int> sizes = {256};
221   brillo::Blob unsigned_payload_hash, unsigned_metadata_hash;
222   EXPECT_TRUE(PayloadSigner::HashPayloadForSigning(
223       payload_path, sizes, &unsigned_payload_hash, &unsigned_metadata_hash));
224   EXPECT_TRUE(payload.WritePayload(
225       payload_path, "/dev/null", kUnittestPrivateKeyPath, &metadata_size));
226   brillo::Blob signed_payload_hash, signed_metadata_hash;
227   EXPECT_TRUE(PayloadSigner::HashPayloadForSigning(
228       payload_path, sizes, &signed_payload_hash, &signed_metadata_hash));
229   EXPECT_EQ(unsigned_payload_hash, signed_payload_hash);
230   EXPECT_EQ(unsigned_metadata_hash, signed_metadata_hash);
231 }
232 
TEST_F(PayloadSignerTest,VerifySignedPayloadTest)233 TEST_F(PayloadSignerTest, VerifySignedPayloadTest) {
234   string payload_path;
235   EXPECT_TRUE(utils::MakeTempFile("payload.XXXXXX", &payload_path, nullptr));
236   ScopedPathUnlinker payload_path_unlinker(payload_path);
237 
238   PayloadGenerationConfig config;
239   config.version.major = kBrilloMajorPayloadVersion;
240   PayloadFile payload;
241   EXPECT_TRUE(payload.Init(config));
242   uint64_t metadata_size;
243   EXPECT_TRUE(payload.WritePayload(
244       payload_path, "/dev/null", kUnittestPrivateKeyPath, &metadata_size));
245   EXPECT_TRUE(PayloadSigner::VerifySignedPayload(payload_path,
246                                                  kUnittestPublicKeyPath));
247 }
248 
249 }  // namespace chromeos_update_engine
250