diff --git a/payload_signer_unittest.cc b/payload_signer_unittest.cc
index f803156..f7c59a6 100644
--- a/payload_signer_unittest.cc
+++ b/payload_signer_unittest.cc
@@ -14,7 +14,7 @@
 using std::vector;
 
 // Note: the test key was generated with the following command:
-// openssl genrsa -out unittest_key.pem 1024
+// openssl genrsa -out unittest_key.pem 2048
 
 namespace chromeos_update_engine {
 
@@ -23,29 +23,55 @@
 
 // Some data and its corresponding hash and signature:
 const char kDataToSign[] = "This is some data to sign.";
+
+// Generated by:
+// echo -n 'This is some data to sign.' | openssl dgst -sha256 -binary |
+//   hexdump -v -e '" " 8/1 "0x%02x, " "\n"'
 const char kDataHash[] = {
   0x7a, 0x07, 0xa6, 0x44, 0x08, 0x86, 0x20, 0xa6,
   0xc1, 0xf8, 0xd9, 0x02, 0x05, 0x63, 0x0d, 0xb7,
   0xfc, 0x2b, 0xa0, 0xa9, 0x7c, 0x9d, 0x1d, 0x8c,
   0x01, 0xf5, 0x78, 0x6d, 0xc5, 0x11, 0xb4, 0x06
 };
+
+// Generated with openssl 1.0, which at the time of this writing, you need
+// to download and install yourself. Here's my command:
+// echo -n 'This is some data to sign.' | openssl dgst -sha256 -binary |
+//    ~/local/bin/openssl pkeyutl -sign -inkey unittest_key.pem -pkeyopt
+//    digest:sha256 | hexdump -v -e '" " 8/1 "0x%02x, " "\n"'
 const char kDataSignature[] = {
-  0xa4, 0xbc, 0x8f, 0xeb, 0x81, 0x05, 0xaa, 0x56,
-  0x1b, 0x56, 0xe5, 0xcb, 0x9b, 0x1a, 0x00, 0xd7,
-  0x1d, 0x87, 0x8e, 0xda, 0x5e, 0x90, 0x09, 0xb8,
-  0x15, 0xf4, 0x25, 0x97, 0x2f, 0x3c, 0xa1, 0xf3,
-  0x02, 0x75, 0xcd, 0x67, 0x4b, 0x0c, 0x1f, 0xf5,
-  0x6e, 0xf1, 0x58, 0xd7, 0x0d, 0x8c, 0x18, 0x91,
-  0x52, 0x30, 0x98, 0x64, 0x58, 0xc0, 0xe2, 0xb5,
-  0x77, 0x3b, 0x96, 0x8f, 0x05, 0xc4, 0x7f, 0x7a,
-  0x9a, 0x44, 0x0f, 0xc7, 0x1b, 0x90, 0x83, 0xf8,
-  0x69, 0x05, 0xa8, 0x02, 0x57, 0xcd, 0x2e, 0x5b,
-  0x96, 0xc7, 0x77, 0xa6, 0x1f, 0x97, 0x97, 0x05,
-  0xb3, 0x30, 0x1c, 0x27, 0xd7, 0x2d, 0x31, 0x60,
-  0x84, 0x7e, 0x99, 0x00, 0xe6, 0xe1, 0x39, 0xa6,
-  0xf3, 0x3a, 0x72, 0xba, 0xc4, 0xfe, 0x68, 0xa9,
-  0x08, 0xfa, 0xbc, 0xa8, 0x44, 0x66, 0xa0, 0x60,
-  0xde, 0xc9, 0xb2, 0xba, 0xbc, 0x80, 0xb5, 0x55
+  0x9f, 0x86, 0x25, 0x8b, 0xf3, 0xcc, 0xe3, 0x95,
+  0x5f, 0x45, 0x83, 0xb2, 0x66, 0xf0, 0x2a, 0xcf,
+  0xb7, 0xaa, 0x52, 0x25, 0x7a, 0xdd, 0x9d, 0x65,
+  0xe5, 0xd6, 0x02, 0x4b, 0x37, 0x99, 0x53, 0x06,
+  0xc2, 0xc9, 0x37, 0x36, 0x25, 0x62, 0x09, 0x4f,
+  0x6b, 0x22, 0xf8, 0xb3, 0x89, 0x14, 0x98, 0x1a,
+  0xbc, 0x30, 0x90, 0x4a, 0x43, 0xf5, 0xea, 0x2e,
+  0xf0, 0xa4, 0xba, 0xc3, 0xa7, 0xa3, 0x44, 0x70,
+  0xd6, 0xc4, 0x89, 0xd8, 0x45, 0x71, 0xbb, 0xee,
+  0x59, 0x87, 0x3d, 0xd5, 0xe5, 0x40, 0x22, 0x3d,
+  0x73, 0x7e, 0x2a, 0x58, 0x93, 0x8e, 0xcb, 0x9c,
+  0xf2, 0xbb, 0x4a, 0xc9, 0xd2, 0x2c, 0x52, 0x42,
+  0xb0, 0xd1, 0x13, 0x22, 0xa4, 0x78, 0xc7, 0xc6,
+  0x3e, 0xf1, 0xdc, 0x4c, 0x7b, 0x2d, 0x40, 0xda,
+  0x58, 0xac, 0x4a, 0x11, 0x96, 0x3d, 0xa0, 0x01,
+  0xf6, 0x96, 0x74, 0xf6, 0x6c, 0x0c, 0x49, 0x69,
+  0x4e, 0xc1, 0x7e, 0x9f, 0x2a, 0x42, 0xdd, 0x15,
+  0x6b, 0x37, 0x2e, 0x3a, 0xa7, 0xa7, 0x6d, 0x91,
+  0x13, 0xe8, 0x59, 0xde, 0xfe, 0x99, 0x07, 0xd9,
+  0x34, 0x0f, 0x17, 0xb3, 0x05, 0x4c, 0xd2, 0xc6,
+  0x82, 0xb7, 0x38, 0x36, 0x63, 0x1d, 0x9e, 0x21,
+  0xa6, 0x32, 0xef, 0xf1, 0x65, 0xe6, 0xed, 0x95,
+  0x25, 0x9b, 0x61, 0xe0, 0xba, 0x86, 0xa1, 0x7f,
+  0xf8, 0xa5, 0x4a, 0x32, 0x1f, 0x15, 0x20, 0x8a,
+  0x41, 0xc5, 0xb0, 0xd9, 0x4a, 0xda, 0x85, 0xf3,
+  0xdc, 0xa0, 0x98, 0x5d, 0x1d, 0x18, 0x9d, 0x2e,
+  0x42, 0xea, 0x69, 0x13, 0x74, 0x3c, 0x74, 0xf7,
+  0x6d, 0x43, 0xb0, 0x63, 0x90, 0xdb, 0x04, 0xd5,
+  0x05, 0xc9, 0x73, 0x1f, 0x6c, 0xd6, 0xfa, 0x46,
+  0x4e, 0x0f, 0x33, 0x58, 0x5b, 0x0d, 0x1b, 0x55,
+  0x39, 0xb9, 0x0f, 0x43, 0x37, 0xc0, 0x06, 0x0c,
+  0x29, 0x93, 0x43, 0xc7, 0x43, 0xb9, 0xab, 0x7d
 };
 
 //class PayloadSignerTest : public ::testing::Test {};
@@ -96,9 +122,11 @@
   EXPECT_TRUE(PayloadSigner::VerifySignature(signature_blob,
                                              kUnittestPublicKeyPath,
                                              &hash_data));
-  ASSERT_EQ(arraysize(kDataHash), hash_data.size());
-  for (size_t i = 0; i < arraysize(kDataHash); i++) {
-    EXPECT_EQ(kDataHash[i], hash_data[i]);
+  vector<char> padded_hash_data(kDataHash, kDataHash + sizeof(kDataHash));
+  PayloadSigner::PadRSA2048SHA256Hash(&padded_hash_data);
+  ASSERT_EQ(padded_hash_data.size(), hash_data.size());
+  for (size_t i = 0; i < padded_hash_data.size(); i++) {
+    EXPECT_EQ(padded_hash_data[i], hash_data[i]);
   }
 }