Check all signatures regardless of the version.
The update_engine daemon had a fixed version number for the public key
used to verify both the metadata and whole payload signatures. The
public key itself is installed by the signer, implying that the source
code and the signer need to be in sync if we ever need to roll the
payload key.
This situation becomes more of a problem if we don't control when the
version number included in the source code is updated in the built
image sent for payload generation and signing.
This patch makes update_engine ignore the version number associated
with a signature and instead tries to verify all the signatures
included in the payload against the public key found in the code. This
effectively deprecates the key version number. To be compatible with
old versions, the version number 1 is included in all signatures.
Bug: 23601118
Test: Added unittests.
Change-Id: I4f96cc207ad6b9c011def5ce586d0e0e85af28ab
diff --git a/payload_verifier.h b/payload_verifier.h
index edaa754..faea31d 100644
--- a/payload_verifier.h
+++ b/payload_verifier.h
@@ -30,26 +30,16 @@
namespace chromeos_update_engine {
-extern const uint32_t kSignatureMessageOriginalVersion;
-extern const uint32_t kSignatureMessageCurrentVersion;
-
class PayloadVerifier {
public:
- // Returns false if the payload signature can't be verified. Returns true
- // otherwise and sets |out_hash| to the signed payload hash.
+ // Interprets |signature_blob| as a protocol buffer containing the Signatures
+ // message and decrypts each signature data using the |public_key_path|.
+ // Returns whether *any* of the decrypted hashes matches the |hash_data|.
+ // In case of any error parsing the signatures or the public key, returns
+ // false.
static bool VerifySignature(const chromeos::Blob& signature_blob,
const std::string& public_key_path,
- chromeos::Blob* out_hash_data);
-
- // Interprets signature_blob as a protocol buffer containing the Signatures
- // message and decrypts the signature data using the public_key_path and
- // stores the resultant raw hash data in out_hash_data. Returns true if
- // everything is successful. False otherwise. It also takes the client_version
- // and interprets the signature blob according to that version.
- static bool VerifySignatureBlob(const chromeos::Blob& signature_blob,
- const std::string& public_key_path,
- uint32_t client_version,
- chromeos::Blob* out_hash_data);
+ const chromeos::Blob& hash_data);
// Decrypts sig_data with the given public_key_path and populates
// out_hash_data with the decoded raw hash. Returns true if successful,
@@ -62,8 +52,7 @@
// verified using the public key in |public_key_path| with the signature
// of a given version in the signature blob. Returns false otherwise.
static bool VerifySignedPayload(const std::string& payload_path,
- const std::string& public_key_path,
- uint32_t client_key_check_version);
+ const std::string& public_key_path);
// Pads a SHA256 hash so that it may be encrypted/signed with RSA2048
// using the PKCS#1 v1.5 scheme.