Merge "Identity Credential: Require passing applicationId when generating attestation."

This commit is contained in:
Treehugger Robot 2020-02-04 21:31:31 +00:00 committed by Gerrit Code Review
commit 7175150e3f
5 changed files with 70 additions and 14 deletions

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@ -620,7 +620,7 @@ db47f4ceceb1f06c656f39caa70c557b0f8471ef59fd58611bea667ffca20101 android.hardwar
0589e410f519e36514e7ece18f283f022df0f70efd2c12821d822f67f74aba98 android.hardware.identity@1.0::types
bbeee9604128ede83ee755b67e73b5ad29e6e1dbac9ec41fea6ffe2745b0c50a android.hardware.identity@1.0::IIdentityCredential
96ce8aad80f4c476f25261f790d357c117e79e18474c7dadd850dac704bbe65e android.hardware.identity@1.0::IIdentityCredentialStore
6e1e28a96c90ba78d47257faea3f3bb4e6360affbbfa5822f0dc31211f9266ff android.hardware.identity@1.0::IWritableIdentityCredential
8da9c938e58f7d636ddd2f92c646f99d9a9e79612e6441b6380ab12744251873 android.hardware.identity@1.0::IWritableIdentityCredential
27ae3724053940462114228872b3ffaf0b8e6177d5ba97f5a76339d12b8a99dd android.hardware.keymaster@4.1::IKeymasterDevice
adb0efdf1462e9b2e742c0dcadd598666aac551f178be06e755bfcdf5797abd0 android.hardware.keymaster@4.1::IOperation
ac429fca0da4ce91218768ec31b64ded88251f8a26d8c4f27c06abdc5b1926d9 android.hardware.keymaster@4.1::types

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@ -26,20 +26,56 @@ interface IWritableIdentityCredential {
* characteristics to an issuing authority. Must not be called more than once.
*
* The certificate chain must be generated using Keymaster Attestation
* (see https://source.android.com/security/keystore/attestation) and must also
* have the Tag::IDENTITY_CREDENTIAL_KEY tag from KeyMaster 4.1 set. This tag indicates
* that this key is an Identity Credential key (which can only sign/MAC very
* specific messages) and not an Android Keystore key (which can be used to sign/MAC
* anything).
* (see https://source.android.com/security/keystore/attestation) with the
* following additional requirements:
*
* - The attestationVersion field in the attestation extension must be at least 3.
*
* - The attestationSecurityLevel field must be set to either Software (0),
* TrustedEnvironment (1), or StrongBox (2) depending on how attestation is
* implemented. Only the default AOSP implementation of this HAL may use
* value 0 (additionally, this implementation must not be used on production
* devices).
*
* - The keymasterVersion field in the attestation extension must be set to (10*major + minor)
* where major and minor are the Identity Credential interface major and minor versions.
* Specifically for this version of the interface (1.0) this value is 10.
*
* - The keymasterSecurityLevel field in the attestation extension must be set to
* either Software (0), TrustedEnvironment (1), or StrongBox (2) depending on how
* the Trusted Application backing the HAL implementation is implemented. Only
* the default AOSP implementation of this HAL may use value 0 (additionally, this
* implementation must not be used on production devices)
*
* - The attestationChallenge field must be set to the passed-in challenge.
*
* - The uniqueId field must be empty.
*
* - The softwareEnforced field in the attestation extension must include
* Tag::ATTESTATION_APPLICATION_ID which must be set to the bytes of the passed-in
* attestationApplicationId.
*
* - The teeEnforced field in the attestation extension must include
* Tag::IDENTITY_CREDENTIAL_KEY. This tag indicates that the key is an Identity
* Credential key (which can only sign/MAC very specific messages) and not an Android
* Keystore key (which can be used to sign/MAC anything).
*
* Additional authorizations may be needed in the softwareEnforced and teeEnforced
* fields - the above is not an exhaustive list.
*
* @param attestationApplicationId is the DER encoded value to be stored
* in Tag::ATTESTATION_APPLICATION_ID. This schema is described in
* https://developer.android.com/training/articles/security-key-attestation#certificate_schema_attestationid
*
* @param attestationChallenge a challenge set by the issuer to ensure freshness.
*
* @return result is OK on success, FAILED if an error occurred.
*
* @return certificate is the X.509 certificate chain for the credentialKey
* @return certificateChain is the X.509 certificate chain for the credentialKey
*/
getAttestationCertificate(vec<uint8_t> attestationChallenge)
generates(Result result, vec<uint8_t> certificate);
getAttestationCertificate(vec<uint8_t> attestationApplicationId,
vec<uint8_t> attestationChallenge)
generates(Result result, vec<vec<uint8_t>> certificateChain);
/**
* Start the personalization process.

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@ -108,7 +108,12 @@ bool WritableIdentityCredential::initialize() {
return true;
}
// TODO: use |attestationApplicationId| and |attestationChallenge| and also
// ensure the returned certificate chain satisfy the requirements listed in
// the docs for IWritableIdentityCredential::getAttestationCertificate()
//
Return<void> WritableIdentityCredential::getAttestationCertificate(
const hidl_vec<uint8_t>& /* attestationApplicationId */,
const hidl_vec<uint8_t>& /* attestationChallenge */,
getAttestationCertificate_cb _hidl_cb) {
// For now, we dynamically generate an attestion key on each and every
@ -181,7 +186,16 @@ Return<void> WritableIdentityCredential::getAttestationCertificate(
certificateChain.insert(certificateChain.end(), attestationKeyCertificate.value().begin(),
attestationKeyCertificate.value().end());
_hidl_cb(support::resultOK(), certificateChain);
optional<vector<vector<uint8_t>>> splitCertChain =
support::certificateChainSplit(certificateChain);
if (!splitCertChain) {
_hidl_cb(support::result(ResultCode::FAILED, "Error splitting certificate chain"), {});
return Void();
}
hidl_vec<hidl_vec<uint8_t>> ret;
ret.resize(splitCertChain.value().size());
std::copy(splitCertChain.value().begin(), splitCertChain.value().end(), ret.begin());
_hidl_cb(support::resultOK(), ret);
return Void();
}

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@ -51,7 +51,8 @@ class WritableIdentityCredential : public IWritableIdentityCredential {
// Methods from ::android::hardware::identity::IWritableIdentityCredential
// follow.
Return<void> getAttestationCertificate(const hidl_vec<uint8_t>& attestationChallenge,
Return<void> getAttestationCertificate(const hidl_vec<uint8_t>& attestationApplicationId,
const hidl_vec<uint8_t>& attestationChallenge,
getAttestationCertificate_cb _hidl_cb) override;
Return<void> startPersonalization(uint16_t accessControlProfileCount,

View file

@ -201,13 +201,18 @@ TEST_P(IdentityCredentialStoreHidlTest, createAndRetrieveCredential) {
ASSERT_NE(writableCredential, nullptr);
string challenge = "attestationChallenge";
// TODO: set it to something random and check it's in the cert chain
vector<uint8_t> attestationApplicationId = {};
vector<uint8_t> attestationChallenge(challenge.begin(), challenge.end());
vector<uint8_t> attestationCertificate;
writableCredential->getAttestationCertificate(
attestationChallenge,
[&](const Result& _result, const hidl_vec<uint8_t>& _attestationCertificate) {
attestationApplicationId, attestationChallenge,
[&](const Result& _result, const hidl_vec<hidl_vec<uint8_t>>& _splitCertChain) {
result = _result;
attestationCertificate = _attestationCertificate;
vector<vector<uint8_t>> splitCerts;
std::copy(_splitCertChain.begin(), _splitCertChain.end(),
std::back_inserter(splitCerts));
attestationCertificate = support::certificateChainJoin(splitCerts);
});
EXPECT_EQ("", result.message);
ASSERT_EQ(ResultCode::OK, result.code);