diff --git a/identity/support/include/android/hardware/identity/support/IdentityCredentialSupport.h b/identity/support/include/android/hardware/identity/support/IdentityCredentialSupport.h
index f7ec7c5..3aa5bb6 100644
--- a/identity/support/include/android/hardware/identity/support/IdentityCredentialSupport.h
+++ b/identity/support/include/android/hardware/identity/support/IdentityCredentialSupport.h
@@ -35,6 +35,9 @@
 using ::std::vector;
 using ::std::pair;
 
+// The semantic tag for a bstr which includes Encoded CBOR (RFC 7049, section 2.4)
+const int kSemanticTagEncodedCbor = 24;
+
 // ---------------------------------------------------------------------------
 // Miscellaneous utilities.
 // ---------------------------------------------------------------------------
@@ -108,45 +111,47 @@
 // ---------------------------------------------------------------------------
 // EC crypto functionality / abstraction (only supports P-256).
 // ---------------------------------------------------------------------------
+
 // Creates an 256-bit EC key using the NID_X9_62_prime256v1 curve, returns the
-// PKCS#8 encoded key-pair.  Also generates an attestation
-// certificate using the |challenge| and |applicationId|, and returns the generated
-// certificate in X.509 certificate chain format.
+// DER encoded private key.  Also generates an attestation using the |challenge|
+// and |applicationId|, and returns the generated certificate chain.
 //
-// The attestation time fields used will be the current time, and expires in one year.
+// The notBeffore field will be the current time and the notAfter will be the same
+// same time as the batch certificate.
 //
 // The first parameter of the return value is the keyPair generated, second return in
 // the pair is the attestation certificate generated.
-optional<std::pair<vector<uint8_t>, vector<vector<uint8_t>>>> createEcKeyPairAndAttestation(
-        const vector<uint8_t>& challenge, const vector<uint8_t>& applicationId);
-
-// Like createEcKeyPairAndAttestation() but allows you to choose the public key.
 //
+optional<std::pair<vector<uint8_t>, vector<vector<uint8_t>>>> createEcKeyPairAndAttestation(
+        const vector<uint8_t>& challenge, const vector<uint8_t>& applicationId,
+        bool isTestCredential);
+
+// (TODO: remove when no longer used by 3rd party.)
 optional<vector<vector<uint8_t>>> createAttestationForEcPublicKey(
         const vector<uint8_t>& publicKey, const vector<uint8_t>& challenge,
         const vector<uint8_t>& applicationId);
 
 // Creates an 256-bit EC key using the NID_X9_62_prime256v1 curve, returns the
-// PKCS#8 encoded key-pair.
+// private key in DER format (as specified in RFC 5915).
 //
 optional<vector<uint8_t>> createEcKeyPair();
 
-// For an EC key |keyPair| encoded in PKCS#8 format, extracts the public key in
+// For an EC key |keyPair| encoded in DER format, extracts the public key in
 // uncompressed point form.
 //
 optional<vector<uint8_t>> ecKeyPairGetPublicKey(const vector<uint8_t>& keyPair);
 
-// For an EC key |keyPair| encoded in PKCS#8 format, extracts the private key as
+// For an EC key |keyPair| encoded in DER format, extracts the private key as
 // an EC uncompressed key.
 //
 optional<vector<uint8_t>> ecKeyPairGetPrivateKey(const vector<uint8_t>& keyPair);
 
-// Creates a PKCS#8 encoded key-pair from a private key (which must be uncompressed,
-// e.g. 32 bytes). The public key is derived from the given private key..
+// Creates a DER encoded representation from a private key (which must be uncompressed,
+// e.g. 32 bytes).
 //
 optional<vector<uint8_t>> ecPrivateKeyToKeyPair(const vector<uint8_t>& privateKey);
 
-// For an EC key |keyPair| encoded in PKCS#8 format, creates a PKCS#12 structure
+// For an EC key |keyPair| encoded in DER format, creates a PKCS#12 structure
 // with the key-pair (not using a password to encrypt the data). The public key
 // in the created structure is included as a certificate, using the given fields
 // |serialDecimal|, |issuer|, |subject|, |validityNotBefore|, and
@@ -209,6 +214,13 @@
 //
 optional<pair<size_t, size_t>> certificateFindSignature(const vector<uint8_t>& x509Certificate);
 
+// Extracts notBefore and notAfter from the top-most certificate in |certificateChain
+// (which should be a concatenated chain of DER-encoded X.509 certificates).
+//
+// Returns notBefore and notAfter in that order.
+//
+optional<pair<time_t, time_t>> certificateGetValidity(const vector<uint8_t>& x509Certificate);
+
 // Generates a X.509 certificate for |publicKey| (which must be in the format
 // returned by ecKeyPairGetPublicKey()).
 //
@@ -351,6 +363,15 @@
 // Utility functions specific to IdentityCredential.
 // ---------------------------------------------------------------------------
 
+optional<vector<uint8_t>> calcMac(const vector<uint8_t>& sessionTranscriptEncoded,
+                                  const string& docType,
+                                  const vector<uint8_t>& deviceNameSpacesEncoded,
+                                  const vector<uint8_t>& eMacKey);
+
+optional<vector<uint8_t>> calcEMacKey(const vector<uint8_t>& privateKey,
+                                      const vector<uint8_t>& publicKey,
+                                      const vector<uint8_t>& sessionTranscriptBytes);
+
 // Returns the testing AES-128 key where all bits are set to 0.
 const vector<uint8_t>& getTestHardwareBoundKey();
 
diff --git a/identity/support/src/IdentityCredentialSupport.cpp b/identity/support/src/IdentityCredentialSupport.cpp
index 747f182..fbf3ab1 100644
--- a/identity/support/src/IdentityCredentialSupport.cpp
+++ b/identity/support/src/IdentityCredentialSupport.cpp
@@ -44,6 +44,7 @@
 
 #include <android-base/logging.h>
 #include <android-base/stringprintf.h>
+#include <charconv>
 
 #include <cppbor.h>
 #include <cppbor_parse.h>
@@ -870,16 +871,97 @@
     return hmac;
 }
 
+int parseDigits(const char** s, int numDigits) {
+    int result;
+    auto [_, ec] = std::from_chars(*s, *s + numDigits, result);
+    if (ec != std::errc()) {
+        LOG(ERROR) << "Error parsing " << numDigits << " digits "
+                   << " from " << s;
+        return 0;
+    }
+    *s += numDigits;
+    return result;
+}
+
+bool parseAsn1Time(const ASN1_TIME* asn1Time, time_t* outTime) {
+    struct tm tm;
+
+    memset(&tm, '\0', sizeof(tm));
+    const char* timeStr = (const char*)asn1Time->data;
+    const char* s = timeStr;
+    if (asn1Time->type == V_ASN1_UTCTIME) {
+        tm.tm_year = parseDigits(&s, 2);
+        if (tm.tm_year < 70) {
+            tm.tm_year += 100;
+        }
+    } else if (asn1Time->type == V_ASN1_GENERALIZEDTIME) {
+        tm.tm_year = parseDigits(&s, 4) - 1900;
+        tm.tm_year -= 1900;
+    } else {
+        LOG(ERROR) << "Unsupported ASN1_TIME type " << asn1Time->type;
+        return false;
+    }
+    tm.tm_mon = parseDigits(&s, 2) - 1;
+    tm.tm_mday = parseDigits(&s, 2);
+    tm.tm_hour = parseDigits(&s, 2);
+    tm.tm_min = parseDigits(&s, 2);
+    tm.tm_sec = parseDigits(&s, 2);
+    // This may need to be updated if someone create certificates using +/- instead of Z.
+    //
+    if (*s != 'Z') {
+        LOG(ERROR) << "Expected Z in string '" << timeStr << "' at offset " << (s - timeStr);
+        return false;
+    }
+
+    time_t t = timegm(&tm);
+    if (t == -1) {
+        LOG(ERROR) << "Error converting broken-down time to time_t";
+        return false;
+    }
+    *outTime = t;
+    return true;
+}
+
 // Generates the attestation certificate with the parameters passed in.  Note
 // that the passed in |activeTimeMilliSeconds| |expireTimeMilliSeconds| are in
 // milli seconds since epoch.  We are setting them to milliseconds due to
 // requirement in AuthorizationSet KM_DATE fields.  The certificate created is
 // actually in seconds.
-optional<vector<vector<uint8_t>>> createAttestation(const EVP_PKEY* key,
-                                                    const vector<uint8_t>& applicationId,
-                                                    const vector<uint8_t>& challenge,
-                                                    uint64_t activeTimeMilliSeconds,
-                                                    uint64_t expireTimeMilliSeconds) {
+//
+// If 0 is passed for expiration time, the expiration time from batch
+// certificate will be used.
+//
+optional<vector<vector<uint8_t>>> createAttestation(
+        const EVP_PKEY* key, const vector<uint8_t>& applicationId, const vector<uint8_t>& challenge,
+        uint64_t activeTimeMilliSeconds, uint64_t expireTimeMilliSeconds, bool isTestCredential) {
+    const keymaster_cert_chain_t* attestation_chain =
+            ::keymaster::getAttestationChain(KM_ALGORITHM_EC, nullptr);
+    if (attestation_chain == nullptr) {
+        LOG(ERROR) << "Error getting attestation chain";
+        return {};
+    }
+    if (expireTimeMilliSeconds == 0) {
+        if (attestation_chain->entry_count < 1) {
+            LOG(ERROR) << "Expected at least one entry in attestation chain";
+            return {};
+        }
+        keymaster_blob_t* bcBlob = &(attestation_chain->entries[0]);
+        const uint8_t* bcData = bcBlob->data;
+        auto bc = X509_Ptr(d2i_X509(nullptr, &bcData, bcBlob->data_length));
+        time_t bcNotAfter;
+        if (!parseAsn1Time(X509_get0_notAfter(bc.get()), &bcNotAfter)) {
+            LOG(ERROR) << "Error getting notAfter from batch certificate";
+            return {};
+        }
+        expireTimeMilliSeconds = bcNotAfter * 1000;
+    }
+    const keymaster_key_blob_t* attestation_signing_key =
+            ::keymaster::getAttestationKey(KM_ALGORITHM_EC, nullptr);
+    if (attestation_signing_key == nullptr) {
+        LOG(ERROR) << "Error getting attestation key";
+        return {};
+    }
+
     ::keymaster::AuthorizationSet auth_set(
             ::keymaster::AuthorizationSetBuilder()
                     .Authorization(::keymaster::TAG_ATTESTATION_CHALLENGE, challenge.data(),
@@ -901,7 +983,7 @@
     ::keymaster::AuthorizationSet swEnforced(::keymaster::AuthorizationSetBuilder().Authorization(
             ::keymaster::TAG_CREATION_DATETIME, activeTimeMilliSeconds));
 
-    ::keymaster::AuthorizationSet hwEnforced(
+    ::keymaster::AuthorizationSetBuilder hwEnforcedBuilder =
             ::keymaster::AuthorizationSetBuilder()
                     .Authorization(::keymaster::TAG_PURPOSE, KM_PURPOSE_SIGN)
                     .Authorization(::keymaster::TAG_KEY_SIZE, 256)
@@ -909,34 +991,29 @@
                     .Authorization(::keymaster::TAG_NO_AUTH_REQUIRED)
                     .Authorization(::keymaster::TAG_DIGEST, KM_DIGEST_SHA_2_256)
                     .Authorization(::keymaster::TAG_EC_CURVE, KM_EC_CURVE_P_256)
-                    .Authorization(::keymaster::TAG_IDENTITY_CREDENTIAL_KEY));
+                    .Authorization(::keymaster::TAG_OS_VERSION, 42)
+                    .Authorization(::keymaster::TAG_OS_PATCHLEVEL, 43);
 
-    const keymaster_cert_chain_t* attestation_chain =
-            ::keymaster::getAttestationChain(KM_ALGORITHM_EC, nullptr);
-
-    if (attestation_chain == nullptr) {
-        LOG(ERROR) << "Error getting attestation chain";
-        return {};
+    // Only include TAG_IDENTITY_CREDENTIAL_KEY if it's not a test credential
+    if (!isTestCredential) {
+        hwEnforcedBuilder.Authorization(::keymaster::TAG_IDENTITY_CREDENTIAL_KEY);
     }
-
-    const keymaster_key_blob_t* attestation_signing_key =
-            ::keymaster::getAttestationKey(KM_ALGORITHM_EC, nullptr);
-    if (attestation_signing_key == nullptr) {
-        LOG(ERROR) << "Error getting attestation key";
-        return {};
-    }
+    ::keymaster::AuthorizationSet hwEnforced(hwEnforcedBuilder);
 
     keymaster_error_t error;
     ::keymaster::CertChainPtr cert_chain_out;
-    ::keymaster::PureSoftKeymasterContext context;
 
-    // set identity version to 10 per hal requirements specified in IWriteableCredential.hal
-    // For now, the identity version in the attestation is set in the keymaster
-    // version field in the portable keymaster lib, which is a bit misleading.
-    uint identity_version = 10;
-    error = generate_attestation_from_EVP(key, swEnforced, hwEnforced, auth_set, context,
-                                          identity_version, *attestation_chain,
-                                          *attestation_signing_key, &cert_chain_out);
+    // Pretend to be implemented in a trusted environment just so we can pass
+    // the VTS tests. Of course, this is a pretend-only game since hopefully no
+    // relying party is ever going to trust our batch key and those keys above
+    // it.
+    //
+    ::keymaster::PureSoftKeymasterContext context(KM_SECURITY_LEVEL_TRUSTED_ENVIRONMENT);
+
+    error = generate_attestation_from_EVP_with_subject_name(
+            key, swEnforced, hwEnforced, auth_set, context, ::keymaster::kCurrentKeymasterVersion,
+            *attestation_chain, *attestation_signing_key, "Android Identity Credential Key",
+            &cert_chain_out);
 
     if (KM_ERROR_OK != error || !cert_chain_out) {
         LOG(ERROR) << "Error generate attestation from EVP key" << error;
@@ -957,7 +1034,8 @@
 }
 
 optional<std::pair<vector<uint8_t>, vector<vector<uint8_t>>>> createEcKeyPairAndAttestation(
-        const vector<uint8_t>& challenge, const vector<uint8_t>& applicationId) {
+        const vector<uint8_t>& challenge, const vector<uint8_t>& applicationId,
+        bool isTestCredential) {
     auto ec_key = ::keymaster::EC_KEY_Ptr(EC_KEY_new());
     auto pkey = ::keymaster::EVP_PKEY_Ptr(EVP_PKEY_new());
     auto group = ::keymaster::EC_GROUP_Ptr(EC_GROUP_new_by_curve_name(NID_X9_62_prime256v1));
@@ -978,12 +1056,11 @@
         return {};
     }
 
-    uint64_t now = time(nullptr);
-    uint64_t secondsInOneYear = 365 * 24 * 60 * 60;
-    uint64_t expireTimeMs = (now + secondsInOneYear) * 1000;
+    uint64_t nowMs = time(nullptr) * 1000;
+    uint64_t expireTimeMs = 0;  // Set to same as batch certificate
 
-    optional<vector<vector<uint8_t>>> attestationCert =
-            createAttestation(pkey.get(), applicationId, challenge, now * 1000, expireTimeMs);
+    optional<vector<vector<uint8_t>>> attestationCert = createAttestation(
+            pkey.get(), applicationId, challenge, nowMs, expireTimeMs, isTestCredential);
     if (!attestationCert) {
         LOG(ERROR) << "Error create attestation from key and challenge";
         return {};
@@ -1031,14 +1108,12 @@
         return {};
     }
 
-    uint64_t now = (std::chrono::duration_cast<std::chrono::nanoseconds>(
-                    std::chrono::system_clock::now().time_since_epoch()).
-                    count()/ 1000000000);
-    uint64_t secondsInOneYear = 365 * 24 * 60 * 60;
-    uint64_t expireTimeMs = (now + secondsInOneYear) * 1000;
+    uint64_t nowMs = time(nullptr) * 1000;
+    uint64_t expireTimeMs = 0;  // Set to same as batch certificate
 
     optional<vector<vector<uint8_t>>> attestationCert =
-            createAttestation(pkey.get(), applicationId, challenge, now * 1000, expireTimeMs);
+            createAttestation(pkey.get(), applicationId, challenge, nowMs, expireTimeMs,
+                              false /* isTestCredential */);
     if (!attestationCert) {
         LOG(ERROR) << "Error create attestation from key and challenge";
         return {};
@@ -1646,6 +1721,32 @@
     return std::make_pair(tbsCertificateOffset, tbsCertificateSize);
 }
 
+optional<pair<time_t, time_t>> certificateGetValidity(const vector<uint8_t>& x509Certificate) {
+    vector<X509_Ptr> certs;
+    if (!parseX509Certificates(x509Certificate, certs)) {
+        LOG(ERROR) << "Error parsing certificates";
+        return {};
+    }
+    if (certs.size() < 1) {
+        LOG(ERROR) << "No certificates in chain";
+        return {};
+    }
+
+    time_t notBefore;
+    time_t notAfter;
+    if (!parseAsn1Time(X509_get0_notBefore(certs[0].get()), &notBefore)) {
+        LOG(ERROR) << "Error parsing notBefore";
+        return {};
+    }
+
+    if (!parseAsn1Time(X509_get0_notAfter(certs[0].get()), &notAfter)) {
+        LOG(ERROR) << "Error parsing notAfter";
+        return {};
+    }
+
+    return std::make_pair(notBefore, notAfter);
+}
+
 optional<pair<size_t, size_t>> certificateFindSignature(const vector<uint8_t>& x509Certificate) {
     vector<X509_Ptr> certs;
     if (!parseX509Certificates(x509Certificate, certs)) {
@@ -2218,6 +2319,49 @@
 // Utility functions specific to IdentityCredential.
 // ---------------------------------------------------------------------------
 
+optional<vector<uint8_t>> calcEMacKey(const vector<uint8_t>& privateKey,
+                                      const vector<uint8_t>& publicKey,
+                                      const vector<uint8_t>& sessionTranscriptBytes) {
+    optional<vector<uint8_t>> sharedSecret = support::ecdh(publicKey, privateKey);
+    if (!sharedSecret) {
+        LOG(ERROR) << "Error performing ECDH";
+        return {};
+    }
+    vector<uint8_t> salt = support::sha256(sessionTranscriptBytes);
+    vector<uint8_t> info = {'E', 'M', 'a', 'c', 'K', 'e', 'y'};
+    optional<vector<uint8_t>> derivedKey = support::hkdf(sharedSecret.value(), salt, info, 32);
+    if (!derivedKey) {
+        LOG(ERROR) << "Error performing HKDF";
+        return {};
+    }
+    return derivedKey.value();
+}
+
+optional<vector<uint8_t>> calcMac(const vector<uint8_t>& sessionTranscriptEncoded,
+                                  const string& docType,
+                                  const vector<uint8_t>& deviceNameSpacesEncoded,
+                                  const vector<uint8_t>& eMacKey) {
+    auto [sessionTranscriptItem, _, errMsg] = cppbor::parse(sessionTranscriptEncoded);
+    if (sessionTranscriptItem == nullptr) {
+        LOG(ERROR) << "Error parsing sessionTranscriptEncoded: " << errMsg;
+        return {};
+    }
+    // The data that is MACed is ["DeviceAuthentication", sessionTranscript, docType,
+    // deviceNameSpacesBytes] so build up that structure
+    cppbor::Array deviceAuthentication =
+            cppbor::Array()
+                    .add("DeviceAuthentication")
+                    .add(std::move(sessionTranscriptItem))
+                    .add(docType)
+                    .add(cppbor::Semantic(kSemanticTagEncodedCbor, deviceNameSpacesEncoded));
+    vector<uint8_t> deviceAuthenticationBytes =
+            cppbor::Semantic(kSemanticTagEncodedCbor, deviceAuthentication.encode()).encode();
+    optional<vector<uint8_t>> calculatedMac =
+            support::coseMac0(eMacKey, {},                 // payload
+                              deviceAuthenticationBytes);  // detached content
+    return calculatedMac;
+}
+
 vector<vector<uint8_t>> chunkVector(const vector<uint8_t>& content, size_t maxChunkSize) {
     vector<vector<uint8_t>> ret;
 
diff --git a/identity/support/tests/IdentityCredentialSupportTest.cpp b/identity/support/tests/IdentityCredentialSupportTest.cpp
index c356549..266f263 100644
--- a/identity/support/tests/IdentityCredentialSupportTest.cpp
+++ b/identity/support/tests/IdentityCredentialSupportTest.cpp
@@ -436,6 +436,300 @@
             support::cborPrettyPrint(mac.value()));
 }
 
+// Generates a private key in DER format for a small value of 'd'.
+//
+// Used for test vectors.
+//
+vector<uint8_t> p256PrivateKeyFromD(uint8_t d) {
+    vector<uint8_t> privateUncompressed;
+    privateUncompressed.resize(32);
+    privateUncompressed[31] = d;
+    optional<vector<uint8_t>> privateKey = support::ecPrivateKeyToKeyPair(privateUncompressed);
+    return privateKey.value();
+}
+
+std::pair<vector<uint8_t>, vector<uint8_t>> p256PrivateKeyGetXandY(
+        const vector<uint8_t> privateKey) {
+    optional<vector<uint8_t>> publicUncompressed = support::ecKeyPairGetPublicKey(privateKey);
+    vector<uint8_t> x = vector<uint8_t>(publicUncompressed.value().begin() + 1,
+                                        publicUncompressed.value().begin() + 33);
+    vector<uint8_t> y = vector<uint8_t>(publicUncompressed.value().begin() + 33,
+                                        publicUncompressed.value().begin() + 65);
+    return std::make_pair(x, y);
+}
+
+const cppbor::Item* findValueForTstr(const cppbor::Map* map, const string& keyValue) {
+    // TODO: Need cast until libcppbor's Map::get() is marked as const
+    auto [item, found] = ((cppbor::Map*)map)->get(keyValue);
+    if (!found) {
+        return nullptr;
+    }
+    return item.get();
+}
+
+const cppbor::Array* findArrayValueForTstr(const cppbor::Map* map, const string& keyValue) {
+    const cppbor::Item* item = findValueForTstr(map, keyValue);
+    if (item == nullptr) {
+        return nullptr;
+    }
+    return item->asArray();
+}
+
+const cppbor::Map* findMapValueForTstr(const cppbor::Map* map, const string& keyValue) {
+    const cppbor::Item* item = findValueForTstr(map, keyValue);
+    if (item == nullptr) {
+        return nullptr;
+    }
+    return item->asMap();
+}
+
+const cppbor::Semantic* findSemanticValueForTstr(const cppbor::Map* map, const string& keyValue) {
+    const cppbor::Item* item = findValueForTstr(map, keyValue);
+    if (item == nullptr) {
+        return nullptr;
+    }
+    return item->asSemantic();
+}
+
+const std::string findStringValueForTstr(const cppbor::Map* map, const string& keyValue) {
+    const cppbor::Item* item = findValueForTstr(map, keyValue);
+    if (item == nullptr) {
+        return nullptr;
+    }
+    const cppbor::Tstr* tstr = item->asTstr();
+    if (tstr == nullptr) {
+        return "";
+    }
+    return tstr->value();
+}
+
+TEST(IdentityCredentialSupport, testVectors_18013_5) {
+    // This is a test against known vectors for ISO 18013-5.
+    //
+    // The objective of this test is to verify that support::calcEMacKey() and
+    // support::calcMac() agree with the given test vectors.
+    //
+
+    // We're given static device key:
+    //
+    //     x: 28412803729898893058558238221310261427084375743576167377786533380249859400145
+    //     y: 65403602826180996396520286939226973026599920614829401631985882360676038096704
+    //     d: 11
+    //
+    vector<uint8_t> deviceKey = p256PrivateKeyFromD(11);
+    auto [deviceKeyX, deviceKeyY] = p256PrivateKeyGetXandY(deviceKey);
+    EXPECT_EQ(support::encodeHex(deviceKeyX),
+              "3ed113b7883b4c590638379db0c21cda16742ed0255048bf433391d374bc21d1");
+    EXPECT_EQ(support::encodeHex(deviceKeyY),
+              "9099209accc4c8a224c843afa4f4c68a090d04da5e9889dae2f8eefce82a3740");
+
+    // We're given Ephemeral reader key:
+    //
+    //   x: 59535862115950685744176693329402396749019581632805653266809849538337418304154
+    //   y: 53776829996815113213100700404832701936765102413212294632483274374518863708344
+    //   d: 20
+    //
+    vector<uint8_t> ephemeralReaderKey = p256PrivateKeyFromD(20);
+    auto [ephemeralReaderKeyX, ephemeralReaderKeyY] = p256PrivateKeyGetXandY(ephemeralReaderKey);
+    EXPECT_EQ(support::encodeHex(ephemeralReaderKeyX),
+              "83a01a9378395bab9bcd6a0ad03cc56d56e6b19250465a94a234dc4c6b28da9a");
+    EXPECT_EQ(support::encodeHex(ephemeralReaderKeyY),
+              "76e49b6de2f73234ae6a5eb9d612b75c9f2202bb6923f54ff8240aaa86f640b8");
+    vector<uint8_t> ephemeralReaderKeyPublic =
+            support::ecKeyPairGetPublicKey(ephemeralReaderKey).value();
+
+    // We're given SessionEstablishment.
+    //
+    //   SessionEstablishment = {
+    //     "eReaderKey" : EReaderKeyBytes,
+    //     "data" : bstr ; Encrypted mdoc request
+    //   }
+    //
+    // Fish out EReaderKey from this.
+    //
+    // Note that the test vector below is incorrect insofar that it uses
+    // "eReaderKeyBytes" instead of just "eReaderKey". This will be corrected in
+    // the future.
+    //
+    optional<vector<uint8_t>> sessionEstablishmentEncoded = support::decodeHex(
+            "a26f655265616465724b65794279746573d818584ba40102200121582083a01a9378395bab9bcd6a0ad03c"
+            "c56d56e6b19250465a94a234dc4c6b28da9a22582076e49b6de2f73234ae6a5eb9d612b75c9f2202bb6923"
+            "f54ff8240aaa86f640b864646174615902d945b31040c57491acb6d46a71f6c1f67a0b837df1bda9089fd0"
+            "3d0b1fdac3eeb2874a4ef6f90c97d03397186ba00a91102faae7e992e15f761d5662c3c37e3c6c2cfd2ebc"
+            "0bf59dbb8795e377bd7dd353230a41ba2d82294b45871a39b42ca531f26b52f46e356fbaf5075c8fd5b8b0"
+            "8a0df4a1d2e1bdd2e5d69169c1efbb51e393e608d833d325bebfbccb2e15ec08f94b264582fa7b93f7cebc"
+            "aa69f4f0cac2744d4fe35b04df26b2ae69273eed33024949080c1c95a6ef046beede959e9494297dd770af"
+            "4ac6fdd56783aa012555c213dc05cf0f41d1c95119720fcfe1621027f80e2ddd56ea3c1fc596f7b2579333"
+            "5a887ec788092b4a69d23b6219e27d0249b50b3fdcb95b5227007689362e0416b3bae3dae7cb56b4394666"
+            "4e3a3f60dce8d0b678fcd754bebf87bd2b0278dd782d952488a46f2874e34c2dd97bb74084a62b850e9719"
+            "252cd1dca7dbf1858193f6cf093cb3735312bbe1138cf29d8f350e285923f8ef07065299926720b42264e8"
+            "fd5d4b133e72f47c4e999ea689c353f8b41e50a59838e1a0d09eca4a557f77a9c389a0591ad1639119ce86"
+            "edc3320130480ee5101effae6066e8c85aac9ead2ae83e49c1e508aab02f753decbb522ea2200d62fd5d26"
+            "094bd35100bffaa1cdc6af9f7e9cfe7b63da6b5671cd5ac2cf5da450c72addc64cde441f3b7f7fdaf930ad"
+            "1e13388e8a7308d8ca4607e59e082db431a232e7e12cb692baeb4b2127e110ff24cea322ffdbc2e4d9c4c6"
+            "bed27753137d07897c8613627a799a560cf1a2d1edb3de029442862940a5ed7785eea8b6ace93aa6af0792"
+            "fd82877f62d07b757d0179ecbb7347004ecc9c0690d41f75f188cb17ffd2cec2ad8c9675466bb33b737a2a"
+            "e7592b2dcb8132aced2e572266f3f5413a5f9d6d4339a1e4662622af2e7e157a4ea3bfd5c4247e2ec91d8c"
+            "5c3c17427d5edfae673d0e0f782a8d40fa805fd8bc82ae3cb21a65cdad863e02309f6b01d1753fa884b778"
+            "f6e019a2004d8964deeb11f1fd478fcb");
+    ASSERT_TRUE(sessionEstablishmentEncoded);
+    auto [sessionEstablishmentItem, _se, _se2] = cppbor::parse(sessionEstablishmentEncoded.value());
+    const cppbor::Map* sessionEstablishment = sessionEstablishmentItem->asMap();
+    ASSERT_NE(sessionEstablishment, nullptr);
+    const cppbor::Semantic* eReaderKeyBytes =
+            findSemanticValueForTstr(sessionEstablishment, "eReaderKeyBytes");
+    ASSERT_NE(eReaderKeyBytes, nullptr);
+    ASSERT_EQ(eReaderKeyBytes->value(), 24);
+    const cppbor::Bstr* eReaderKeyBstr = eReaderKeyBytes->child()->asBstr();
+    ASSERT_NE(eReaderKeyBstr, nullptr);
+    vector<uint8_t> eReaderKeyEncoded = eReaderKeyBstr->value();
+    // TODO: verify this agrees with ephemeralReaderKeyX and ephemeralReaderKeyY
+
+    // We're given DeviceEngagement.
+    //
+    vector<uint8_t> deviceEngagementEncoded =
+            support::decodeHex(
+                    "a20063312e30018201d818584ba401022001215820cef66d6b2a3a993e591214d1ea223fb545ca"
+                    "6c471c48306e4c36069404c5723f225820878662a229aaae906e123cdd9d3b4c10590ded29fe75"
+                    "1eeeca34bbaa44af0773")
+                    .value();
+
+    // Now calculate SessionTranscriptBytes. It is defined as
+    //
+    //   SessionTranscript = [
+    //      DeviceEngagementBytes,
+    //      EReaderKeyBytes,
+    //      Handover
+    //   ]
+    //
+    //   SessionTranscriptBytes = #6.24(bstr .cbor SessionTranscript)
+    //
+    cppbor::Array sessionTranscript;
+    sessionTranscript.add(cppbor::Semantic(24, deviceEngagementEncoded));
+    sessionTranscript.add(cppbor::Semantic(24, eReaderKeyEncoded));
+    sessionTranscript.add(cppbor::Null());
+    vector<uint8_t> sessionTranscriptEncoded = sessionTranscript.encode();
+    vector<uint8_t> sessionTranscriptBytes =
+            cppbor::Semantic(24, sessionTranscriptEncoded).encode();
+
+    // The expected EMacKey is 4c1ebb8aacc633465390fa44edfdb49cb57f2e079aaa771d812584699c0b97e2
+    //
+    // Verify that support::calcEMacKey() gets the same result.
+    //
+    optional<vector<uint8_t>> eMacKey =
+            support::calcEMacKey(support::ecKeyPairGetPrivateKey(deviceKey).value(),  // private key
+                                 ephemeralReaderKeyPublic,                            // public key
+                                 sessionTranscriptBytes);  // sessionTranscriptBytes
+    ASSERT_TRUE(eMacKey);
+    ASSERT_EQ(support::encodeHex(eMacKey.value()),
+              "4c1ebb8aacc633465390fa44edfdb49cb57f2e079aaa771d812584699c0b97e2");
+
+    // Also do it the other way around
+    //
+    optional<vector<uint8_t>> eMacKey2 = support::calcEMacKey(
+            support::ecKeyPairGetPrivateKey(ephemeralReaderKey).value(),  // private key
+            support::ecKeyPairGetPublicKey(deviceKey).value(),            // public key
+            sessionTranscriptBytes);                                      // sessionTranscriptBytes
+    ASSERT_TRUE(eMacKey2);
+    ASSERT_EQ(support::encodeHex(eMacKey2.value()),
+              "4c1ebb8aacc633465390fa44edfdb49cb57f2e079aaa771d812584699c0b97e2");
+
+    // We're given DeviceResponse
+    //
+    vector<uint8_t> deviceResponseEncoded =
+            support::decodeHex(
+                    "a36776657273696f6e63312e3069646f63756d656e747381a367646f6354797065756f72672e69"
+                    "736f2e31383031332e352e312e6d444c6c6973737565725369676e6564a26a6e616d6553706163"
+                    "6573a2716f72672e69736f2e31383031332e352e3181d8185863a4686469676573744944016672"
+                    "616e646f6d58208798645b20ea200e19ffabac92624bee6aec63aceedecfb1b80077d22bfc20e9"
+                    "71656c656d656e744964656e7469666965726b66616d696c795f6e616d656c656c656d656e7456"
+                    "616c756563446f656b636f6d2e6578616d706c6581d8185864a468646967657374494401667261"
+                    "6e646f6d5820218ecf13521b53f4b96abaebe56417afec0e4c91fc8fb26086cd1e5cdc1a94ff71"
+                    "656c656d656e744964656e7469666965726f616e6f746865725f656c656d656e746c656c656d65"
+                    "6e7456616c75650a6a697373756572417574688443a10126a118215901d2308201ce30820174a0"
+                    "0302010202141f7d44f4f107c5ee3f566049cf5d72de294b0d23300a06082a8648ce3d04030230"
+                    "233114301206035504030c0b75746f7069612069616361310b3009060355040613025553301e17"
+                    "0d3230313030313030303030305a170d3231313030313030303030305a30213112301006035504"
+                    "030c0975746f706961206473310b30090603550406130255533059301306072a8648ce3d020106"
+                    "082a8648ce3d03010703420004301d9e502dc7e05da85da026a7ae9aa0fac9db7d52a95b3e3e3f"
+                    "9aa0a1b45b8b6551b6f6b3061223e0d23c026b017d72298d9ae46887ca61d58db6aea17ee267a3"
+                    "8187308184301e0603551d120417301581136578616d706c65406578616d706c652e636f6d301c"
+                    "0603551d1f041530133011a00fa00d820b6578616d706c652e636f6d301d0603551d0e04160414"
+                    "7bef4db59a1ffb07592bfc57f4743b8a73aea792300e0603551d0f0101ff040403020780301506"
+                    "03551d250101ff040b3009060728818c5d050102300a06082a8648ce3d04030203480030450220"
+                    "21d52fb1fbda80e5bfda1e8dfb1bc7bf0acb7261d5c9ff54425af76eb21571c602210082bf301f"
+                    "89e0a2cb9ca9c9050352de80b47956764f7a3e07bf6a8cd87528a3b55901d2d8185901cda66776"
+                    "657273696f6e63312e306f646967657374416c676f726974686d675348412d3235366c76616c75"
+                    "6544696765737473a2716f72672e69736f2e31383031332e352e31a20058203b22af1126771f02"
+                    "f0ea0d546d4ee3c5b51637381154f5211b79daf5f9facaa8015820f2cba0ce3cde5df901a3da75"
+                    "13a4d7f7225fdfe5a306544529bf3dbcce655ca06b636f6d2e6578616d706c65a200582072636d"
+                    "ddc282424a63499f4b3927aaa3b74da7b9c0134178bf735e949e4a761e01582006322d3cbe6603"
+                    "876bdacc5b6679b51b0fc53d029c244fd5ea719d9028459c916d6465766963654b6579496e666f"
+                    "a1696465766963654b6579a4010220012158203ed113b7883b4c590638379db0c21cda16742ed0"
+                    "255048bf433391d374bc21d12258209099209accc4c8a224c843afa4f4c68a090d04da5e9889da"
+                    "e2f8eefce82a374067646f6354797065756f72672e69736f2e31383031332e352e312e6d444c6c"
+                    "76616c6964697479496e666fa3667369676e6564c074323032302d31302d30315431333a33303a"
+                    "30325a6976616c696446726f6dc074323032302d31302d30315431333a33303a30325a6a76616c"
+                    "6964556e74696cc074323032312d31302d30315431333a33303a30325a5840273ec1b59817d571"
+                    "b5a2c5c0ab0ea213d42acb18547fd7097afcc888a22ecbb863c6461ce0e240880895b4aaa84308"
+                    "784571c7be7aa3a2e7e3a2ea1a145ed1966c6465766963655369676e6564a26a6e616d65537061"
+                    "636573d81841a06a64657669636541757468a1696465766963654d61638443a10105a0f6582009"
+                    "da7c964ac004ec36ec64edd0c1abf50c03433c215c3ddb144768abcdf20a60667374617475730"
+                    "0")
+                    .value();
+    auto [deviceResponseItem, _, _2] = cppbor::parse(deviceResponseEncoded);
+    const cppbor::Map* deviceResponse = deviceResponseItem->asMap();
+    ASSERT_NE(deviceResponse, nullptr);
+    const cppbor::Array* documents = findArrayValueForTstr(deviceResponse, "documents");
+    ASSERT_NE(documents, nullptr);
+    ASSERT_EQ(documents->size(), 1);
+    const cppbor::Map* document = ((*documents)[0])->asMap();
+    ASSERT_NE(document, nullptr);
+
+    // Get docType
+    string docType = findStringValueForTstr(document, "docType");
+    ASSERT_EQ(docType, "org.iso.18013.5.1.mDL");
+
+    // Drill down...
+    const cppbor::Map* deviceSigned = findMapValueForTstr(document, "deviceSigned");
+    ASSERT_NE(deviceSigned, nullptr);
+
+    // Dig out the encoded form of DeviceNameSpaces
+    //
+    const cppbor::Semantic* deviceNameSpacesBytes =
+            findSemanticValueForTstr(deviceSigned, "nameSpaces");
+    ASSERT_NE(deviceNameSpacesBytes, nullptr);
+    ASSERT_EQ(deviceNameSpacesBytes->value(), 24);
+    const cppbor::Bstr* deviceNameSpacesBstr = deviceNameSpacesBytes->child()->asBstr();
+    ASSERT_NE(deviceNameSpacesBstr, nullptr);
+    vector<uint8_t> deviceNameSpacesEncoded = deviceNameSpacesBstr->value();
+
+    // (For this version of 18013-5, DeviceNameSpaces is always supposed to be empty, check that.)
+    EXPECT_EQ(deviceNameSpacesEncoded, cppbor::Map().encode());
+
+    const cppbor::Map* deviceAuth = findMapValueForTstr(deviceSigned, "deviceAuth");
+    ASSERT_NE(deviceAuth, nullptr);
+    // deviceMac is is the COSE_Mac0.. dig out the encoded form to check that
+    // support::calcMac() gives exactly the same bytes.
+    //
+    const cppbor::Array* deviceMac = findArrayValueForTstr(deviceAuth, "deviceMac");
+    ASSERT_NE(deviceMac, nullptr);
+    vector<uint8_t> deviceMacEncoded = deviceMac->encode();
+
+    // Now we calculate what it should be..
+    optional<vector<uint8_t>> calculatedMac =
+            support::calcMac(sessionTranscriptEncoded,  // SessionTranscript
+                             docType,                   // DocType
+                             deviceNameSpacesEncoded,   // DeviceNamespaces
+                             eMacKey.value());          // EMacKey
+    ASSERT_TRUE(calculatedMac);
+
+    // ... and hopefully it's the same!
+    ASSERT_EQ(calculatedMac.value().size(), deviceMacEncoded.size());
+    EXPECT_TRUE(memcmp(calculatedMac.value().data(), deviceMacEncoded.data(),
+                       deviceMacEncoded.size()) == 0);
+}
+
 }  // namespace identity
 }  // namespace hardware
 }  // namespace android