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Merged
mdwivedi merged 1 commit into from
Mar 26, 2022
Merged

seperating generate key and attest key functionality from generatekey… #103

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22 changes: 11 additions & 11 deletions Applet/AndroidSEProvider/src/com/android/javacard/keymaster/KMAndroidSEApplet.java
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Original file line number Diff line number Diff line change
Expand Up @@ -49,7 +49,7 @@ public class KMAndroidSEApplet extends KMKeymasterApplet implements OnUpgradeLis
private static final byte INS_LOCK_PROVISIONING_CMD = INS_KEYMINT_PROVIDER_APDU_START + 3;
private static final byte INS_GET_PROVISION_STATUS_CMD = INS_KEYMINT_PROVIDER_APDU_START + 4;
private static final byte INS_SET_BOOT_PARAMS_CMD = INS_KEYMINT_PROVIDER_APDU_START + 5;
private static final byte INS_PROVISION_RKP_UNIQUE_DEVICE_KEYPAIR_CMD =
private static final byte INS_PROVISION_RKP_DEVICE_UNIQUE_KEYPAIR_CMD =
INS_KEYMINT_PROVIDER_APDU_START + 6;
private static final byte INS_PROVISION_RKP_ADDITIONAL_CERT_CHAIN_CMD =
INS_KEYMINT_PROVIDER_APDU_START + 7;
Expand All @@ -68,7 +68,7 @@ public class KMAndroidSEApplet extends KMKeymasterApplet implements OnUpgradeLis
private static final byte PROVISION_STATUS_ATTEST_IDS = 0x08;
private static final byte PROVISION_STATUS_PRESHARED_SECRET = 0x10;
private static final byte PROVISION_STATUS_PROVISIONING_LOCKED = 0x20;
private static final byte PROVISION_STATUS_UNIQUE_DEVICE_KEYPAIR = 0x40;
private static final byte PROVISION_STATUS_DEVICE_UNIQUE_KEYPAIR = 0x40;
private static final byte PROVISION_STATUS_ADDITIONAL_CERT_CHAIN = (byte) 0x80;

public static final short SHARED_SECRET_KEY_SIZE = 32;
Expand Down Expand Up @@ -159,12 +159,12 @@ public void process(APDU apdu) {
processSetBootParamsCmd(apdu);
break;

case INS_PROVISION_RKP_UNIQUE_DEVICE_KEYPAIR_CMD:
processProvisionDeviceUniqueKeyPair(apdu);
case INS_PROVISION_RKP_DEVICE_UNIQUE_KEYPAIR_CMD:
processProvisionRkpDeviceUniqueKeyPair(apdu);
break;

case INS_PROVISION_RKP_ADDITIONAL_CERT_CHAIN_CMD:
processProvisionAdditionalCertChain(apdu);
processProvisionRkpAdditionalCertChain(apdu);
break;

default:
Expand All @@ -189,7 +189,7 @@ public void process(APDU apdu) {
}
}

private static void processProvisionDeviceUniqueKeyPair(APDU apdu) {
private static void processProvisionRkpDeviceUniqueKeyPair(APDU apdu) {
// Re-purpose the apdu buffer as scratch pad.
byte[] scratchPad = apdu.getBuffer();
short arr = KMArray.instance((short) 1);
Expand All @@ -201,17 +201,17 @@ private static void processProvisionDeviceUniqueKeyPair(APDU apdu) {
short pubKeyLen = KMCoseKey.cast(coseKey).getEcdsa256PublicKey(scratchPad, (short) 0);
short privKeyLen = KMCoseKey.cast(coseKey).getPrivateKey(scratchPad, pubKeyLen);
//Store the Device unique Key.
kmDataStore.createDeviceUniqueKeyPair(scratchPad, (short) 0, pubKeyLen, scratchPad,
kmDataStore.createRkpDeviceUniqueKeyPair(scratchPad, (short) 0, pubKeyLen, scratchPad,
pubKeyLen, privKeyLen);
short bcc = generateBcc(false, scratchPad);
short len = KMKeymasterApplet.encodeToApduBuffer(bcc, scratchPad, (short) 0,
MAX_COSE_BUF_SIZE);
kmDataStore.persistBootCertificateChain(scratchPad, (short) 0, len);
kmDataStore.setProvisionStatus(PROVISION_STATUS_UNIQUE_DEVICE_KEYPAIR);
kmDataStore.setProvisionStatus(PROVISION_STATUS_DEVICE_UNIQUE_KEYPAIR);
sendError(apdu, KMError.OK);
}

private static void processProvisionAdditionalCertChain(APDU apdu) {
private static void processProvisionRkpAdditionalCertChain(APDU apdu) {
// Prepare the expression to decode
short headers = KMCoseHeaders.exp();
short arrInst = KMArray.instance((short) 4);
Expand Down Expand Up @@ -244,7 +244,7 @@ private static void processProvisionAdditionalCertChain(APDU apdu) {
srcBuffer, null);
// Compare the DK_Pub.
short pubKeyLen = KMCoseKey.cast(leafCoseKey).getEcdsa256PublicKey(srcBuffer, (short) 0);
KMDeviceUniqueKeyPair uniqueKey = kmDataStore.getDeviceUniqueKeyPair(false);
KMDeviceUniqueKeyPair uniqueKey = kmDataStore.getRkpDeviceUniqueKeyPair(false);
if (uniqueKey == null) {
KMException.throwIt(KMError.STATUS_FAILED);
}
Expand Down Expand Up @@ -408,7 +408,7 @@ private boolean isProvisioningComplete() {
byte data[] = repository.getHeap();
kmDataStore.getProvisionStatus(data, dInex);
boolean result = false;
if ((0 != (data[dInex] & PROVISION_STATUS_UNIQUE_DEVICE_KEYPAIR))
if ((0 != (data[dInex] & PROVISION_STATUS_DEVICE_UNIQUE_KEYPAIR))
&& (0 != (data[dInex] & PROVISION_STATUS_ADDITIONAL_CERT_CHAIN))
&& (0 != (data[dInex] & PROVISION_STATUS_PRESHARED_SECRET))) {
result = true;
Expand Down
2 changes: 1 addition & 1 deletion Applet/AndroidSEProviderLib/src/com/android/javacard/seprovider/KMAndroidSEProvider.java
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Original file line number Diff line number Diff line change
Expand Up @@ -1108,7 +1108,7 @@ public short ecSign256(KMDeviceUniqueKeyPair ecPrivKey, byte[] inputDataBuf,
}

@Override
public KMDeviceUniqueKeyPair createDeviceUniqueKeyPair(KMDeviceUniqueKeyPair key,
public KMDeviceUniqueKeyPair createRkpDeviceUniqueKeyPair(KMDeviceUniqueKeyPair key,
byte[] pubKey, short pubKeyOff, short pubKeyLen, byte[] privKey,
short privKeyOff, short privKeyLen) {
if (key == null) {
Expand Down
2 changes: 1 addition & 1 deletion ...avacard/seprovider/KMDeviceUniqueKey.java → ...ard/seprovider/KMDeviceUniqueKeyPair.java
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Original file line number Diff line number Diff line change
Expand Up @@ -15,7 +15,7 @@
*/
package com.android.javacard.seprovider;

public interface KMDeviceUniqueKey {
public interface KMDeviceUniqueKeyPair {

short getPublicKey(byte[] buf, short offset);
}
2 changes: 1 addition & 1 deletion Applet/AndroidSEProviderLib/src/com/android/javacard/seprovider/KMSEProvider.java
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Original file line number Diff line number Diff line change
Expand Up @@ -626,7 +626,7 @@ KMOperation initAsymmetricOperation(
* @param privKeyLen private key buffer length.
* @return instance of KMDeviceUniqueKey.
*/
KMDeviceUniqueKeyPair createDeviceUniqueKeyPair(KMDeviceUniqueKeyPair key,
KMDeviceUniqueKeyPair createRkpDeviceUniqueKeyPair(KMDeviceUniqueKeyPair key,
byte[] pubKey, short pubKeyOff, short pubKeyLen,
byte[] privKey, short privKeyOff, short privKeyLen);

Expand Down
99 changes: 80 additions & 19 deletions Applet/src/com/android/javacard/keymaster/KMKeymasterApplet.java
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Original file line number Diff line number Diff line change
Expand Up @@ -396,6 +396,9 @@ public void process(APDU apdu) {
case INS_GENERATE_KEY_CMD:
processGenerateKey(apdu);
break;
case INS_ATTEST_KEY_CMD:
processAttestKeyCmd(apdu);
break;
case INS_IMPORT_KEY_CMD:
processImportKeyCmd(apdu);
break;
Expand Down Expand Up @@ -1283,16 +1286,17 @@ private KMAttestationCert makeAttestationCert(short attKeyBlob, short attKeyPara

// Add Tags
addTags(hwParameters, true, cert);
addTags(swParameters, false, cert);
short swParams = KMKeyParameters.makeKeystoreEnforced(data[KEY_PARAMETERS], scratchPad);
addTags(swParams, false, cert);
// Add Device Boot locked status
cert.deviceLocked(kmDataStore.isDeviceBootLocked());
// VB data
cert.verifiedBootHash(getVerifiedBootHash(scratchPad));
cert.verifiedBootKey(getBootKey(scratchPad));
cert.verifiedBootState((byte) kmDataStore.getBootState());

// TODO remove the following line
makeKeyCharacteristics(scratchPad);
data[SECRET] = privKey;
data[KEY_BLOB] = origBlob;
return cert;
}

Expand Down Expand Up @@ -3294,13 +3298,9 @@ protected void setVendorPatchLevel(short patch){

private short generateKeyCmd(APDU apdu){
short params = KMKeyParameters.expAny();
short blob = KMByteBlob.exp();
// Array of expected arguments
short cmd = KMArray.instance((short) 4);
short cmd = KMArray.instance((short) 1);
KMArray.cast(cmd).add((short) 0, params); //key params
KMArray.cast(cmd).add((short) 1, blob); //attest key
KMArray.cast(cmd).add((short) 2, params); //attest key params
KMArray.cast(cmd).add((short) 3, blob); //issuer
return receiveIncoming(apdu, cmd);
}

Expand All @@ -3310,10 +3310,6 @@ private void processGenerateKey(APDU apdu) {
// Re-purpose the apdu buffer as scratch pad.
byte[] scratchPad = apdu.getBuffer();
data[KEY_PARAMETERS] = KMArray.cast(cmd).get((short) 0);
data[ATTEST_KEY_BLOB] = KMArray.cast(cmd).get((short) 1);
data[ATTEST_KEY_PARAMS] = KMArray.cast(cmd).get((short) 2);
data[ATTEST_KEY_ISSUER] = KMArray.cast(cmd).get((short) 3);
data[CERTIFICATE] = KMArray.instance((short)0); //by default the cert is empty.
// ROLLBACK_RESISTANCE not supported.
KMTag.assertAbsence(data[KEY_PARAMETERS], KMType.BOOL_TAG,KMType.ROLLBACK_RESISTANCE, KMError.ROLLBACK_RESISTANCE_UNAVAILABLE);

Expand Down Expand Up @@ -3359,22 +3355,84 @@ private void processGenerateKey(APDU apdu) {
// create key blob and associated attestation.
data[ORIGIN] = KMType.GENERATED;
makeKeyCharacteristics(scratchPad);
generateAttestation(data[ATTEST_KEY_BLOB], data[ATTEST_KEY_PARAMS],scratchPad);
createEncryptedKeyBlob(scratchPad);
// Remove custom tags from key characteristics
short teeParams = KMKeyCharacteristics.cast(data[KEY_CHARACTERISTICS]).getTeeEnforced();
if(teeParams != KMType.INVALID_VALUE) {
KMKeyParameters.cast(teeParams).deleteCustomTags();
}
// prepare the response
short resp = KMArray.instance((short) 4);
short resp = KMArray.instance((short) 3);
KMArray.cast(resp).add((short) 0, KMInteger.uint_16(KMError.OK));
KMArray.cast(resp).add((short) 1, data[KEY_BLOB]);
KMArray.cast(resp).add((short) 2, data[KEY_CHARACTERISTICS]);
KMArray.cast(resp).add((short) 3, data[CERTIFICATE]);
sendOutgoing(apdu, resp);
}

private short generateAttestKeyCmd(APDU apdu) {
short params = KMKeyParameters.expAny();
short blob = KMByteBlob.exp();
// Array of expected arguments
short cmd = KMArray.instance((short) 5);
KMArray.cast(cmd).add((short) 0, blob); // key blob
KMArray.cast(cmd).add((short) 1, params); // keyparamters to be attested.
KMArray.cast(cmd).add((short) 2, blob); // attest key blob
KMArray.cast(cmd).add((short) 3, params); // attest key params
KMArray.cast(cmd).add((short) 4, blob); // attest issuer

return receiveIncoming(apdu, cmd);
}

public void getAttestKeyInputParameters(short arrPtr, short[] data, byte keyBlobOff,
byte keyParametersOff,
byte attestKeyBlobOff, byte attestKeyParamsOff, byte attestKeyIssuerOff) {
data[keyBlobOff] = KMArray.cast(arrPtr).get((short) 0);
data[keyParametersOff] = KMArray.cast(arrPtr).get((short) 1);
data[attestKeyBlobOff] = KMType.INVALID_VALUE;
data[attestKeyParamsOff] = KMType.INVALID_VALUE;
data[attestKeyIssuerOff] = KMType.INVALID_VALUE;
}

private void processAttestKeyCmd(APDU apdu) {
// Receive the incoming request fully from the master into buffer.
short cmd = generateAttestKeyCmd(apdu);
// Re-purpose the apdu buffer as scratch pad.
byte[] scratchPad = apdu.getBuffer();
data[KEY_BLOB] = KMArray.cast(cmd).get((short) 0);
data[KEY_PARAMETERS] = KMArray.cast(cmd).get((short) 1);
data[ATTEST_KEY_BLOB] = KMArray.cast(cmd).get((short) 2);
data[ATTEST_KEY_PARAMS] = KMArray.cast(cmd).get((short) 3);
data[ATTEST_KEY_ISSUER] = KMArray.cast(cmd).get((short) 4);

data[CERTIFICATE] = KMArray.instance((short) 0); //by default the cert is empty.

// Check for app id and app data.
data[APP_ID] =
KMKeyParameters.findTag(KMType.BYTES_TAG, KMType.APPLICATION_ID, data[KEY_PARAMETERS]);
data[APP_DATA] =
KMKeyParameters.findTag(KMType.BYTES_TAG, KMType.APPLICATION_DATA, data[KEY_PARAMETERS]);
if (data[APP_ID] != KMTag.INVALID_VALUE) {
data[APP_ID] = KMByteTag.cast(data[APP_ID]).getValue();
}
if (data[APP_DATA] != KMTag.INVALID_VALUE) {
data[APP_DATA] = KMByteTag.cast(data[APP_DATA]).getValue();
}
// parse key blob
parseEncryptedKeyBlob(data[KEY_BLOB], data[APP_ID], data[APP_DATA], scratchPad);
// The key which is being attested should be asymmetric i.e. RSA or EC
short alg = KMEnumTag.getValue(KMType.ALGORITHM, data[HW_PARAMETERS]);
if (alg != KMType.RSA && alg != KMType.EC) {
KMException.throwIt(KMError.INCOMPATIBLE_ALGORITHM);
}
// Build certificate
generateAttestation(data[ATTEST_KEY_BLOB], data[ATTEST_KEY_PARAMS], scratchPad);

short resp = KMArray.instance((short) 2);
KMArray.cast(resp).add((short) 0, KMInteger.uint_16(KMError.OK));
KMArray.cast(resp).add((short) 1, data[CERTIFICATE]);
sendOutgoing(apdu, resp);
}

private short getAttestationMode(short attKeyBlob, short attChallenge){
short alg = KMKeyParameters.findTag(KMType.ENUM_TAG, KMType.ALGORITHM, data[KEY_PARAMETERS]);
short mode = KMType.NO_CERT;
Expand Down Expand Up @@ -3419,7 +3477,7 @@ private void generateAttestation(short attKeyBlob, short attKeyParam, byte[] sc

switch (mode){
case KMType.ATTESTATION_CERT:
cert = makeAttestationCert(attKeyBlob,attKeyParam, attChallenge, data[ATTEST_KEY_ISSUER],data[HW_PARAMETERS],
cert = makeAttestationCert(attKeyBlob, attKeyParam, attChallenge, data[ATTEST_KEY_ISSUER],data[HW_PARAMETERS],
data[SW_PARAMETERS], scratchPad);
break;
case KMType.SELF_SIGNED_CERT:
Expand Down Expand Up @@ -3838,7 +3896,7 @@ private static void makeAuthData(byte[] scratchPad) {
KMArray.cast(params).add((short) 2, data[PUB_KEY]);
}

short authIndex = repository.alloc(MAX_AUTH_DATA_SIZE);
short authIndex = repository.allocReclaimableMemory(MAX_AUTH_DATA_SIZE);
short index = 0;
short len = 0;
short paramsLen = KMArray.cast(params).length();
Expand All @@ -3855,7 +3913,10 @@ private static void makeAuthData(byte[] scratchPad) {
}
index++;
}
data[AUTH_DATA] = authIndex;
short authDataIndex = repository.alloc(len);
Util.arrayCopyNonAtomic(repository.getHeap(), authIndex, repository.getHeap(), authDataIndex, len);
repository.reclaimMemory(MAX_AUTH_DATA_SIZE);
data[AUTH_DATA] = authDataIndex;
data[AUTH_DATA_LENGTH] = len;
}

Expand Down Expand Up @@ -4055,7 +4116,7 @@ public static short generateBcc(boolean testMode, byte[] scratchPad) {
if (!testMode && kmDataStore.isProvisionLocked()) {
KMException.throwIt(KMError.STATUS_FAILED);
}
KMDeviceUniqueKeyPair deviceUniqueKey = kmDataStore.getDeviceUniqueKeyPair(testMode);
KMDeviceUniqueKeyPair deviceUniqueKey = kmDataStore.getRkpDeviceUniqueKeyPair(testMode);
short temp = deviceUniqueKey.getPublicKey(scratchPad, (short) 0);
short coseKey =
KMCose.constructCoseKey(
Expand Down
14 changes: 7 additions & 7 deletions Applet/src/com/android/javacard/keymaster/KMKeymintDataStore.java
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Original file line number Diff line number Diff line change
Expand Up @@ -530,35 +530,35 @@ public KMComputedHmacKey getComputedHmacKey() {
return computedHmacKey;
}

public KMDeviceUniqueKeyPair createTestDeviceUniqueKeyPair(byte[] pubKey, short pubKeyOff, short pubKeyLen,
public KMDeviceUniqueKeyPair createRkpTestDeviceUniqueKeyPair(byte[] pubKey, short pubKeyOff, short pubKeyLen,
byte[] privKey, short privKeyOff, short privKeyLen) {
if (testDeviceUniqueKeyPair == null) {
testDeviceUniqueKeyPair = seProvider.createDeviceUniqueKeyPair(testDeviceUniqueKeyPair, pubKey, pubKeyOff,
testDeviceUniqueKeyPair = seProvider.createRkpDeviceUniqueKeyPair(testDeviceUniqueKeyPair, pubKey, pubKeyOff,
pubKeyLen, privKey,
privKeyOff, privKeyLen);
} else {
seProvider.createDeviceUniqueKeyPair(testDeviceUniqueKeyPair, pubKey, pubKeyOff, pubKeyLen, privKey,
seProvider.createRkpDeviceUniqueKeyPair(testDeviceUniqueKeyPair, pubKey, pubKeyOff, pubKeyLen, privKey,
privKeyOff,
privKeyLen);
}
return testDeviceUniqueKeyPair;
}

public KMDeviceUniqueKeyPair createDeviceUniqueKeyPair(byte[] pubKey, short pubKeyOff, short pubKeyLen,
public KMDeviceUniqueKeyPair createRkpDeviceUniqueKeyPair(byte[] pubKey, short pubKeyOff, short pubKeyLen,
byte[] privKey, short privKeyOff,
short privKeyLen) {
if (deviceUniqueKeyPair == null) {
deviceUniqueKeyPair = seProvider.createDeviceUniqueKeyPair(deviceUniqueKeyPair, pubKey, pubKeyOff,
deviceUniqueKeyPair = seProvider.createRkpDeviceUniqueKeyPair(deviceUniqueKeyPair, pubKey, pubKeyOff,
pubKeyLen, privKey,
privKeyOff, privKeyLen);
} else {
seProvider.createDeviceUniqueKeyPair(deviceUniqueKeyPair, pubKey, pubKeyOff, pubKeyLen, privKey,
seProvider.createRkpDeviceUniqueKeyPair(deviceUniqueKeyPair, pubKey, pubKeyOff, pubKeyLen, privKey,
privKeyOff, privKeyLen);
}
return deviceUniqueKeyPair;
}

public KMDeviceUniqueKeyPair getDeviceUniqueKeyPair(boolean testMode) {
public KMDeviceUniqueKeyPair getRkpDeviceUniqueKeyPair(boolean testMode) {
return ((KMDeviceUniqueKeyPair) (testMode ? testDeviceUniqueKeyPair : deviceUniqueKeyPair));
}

Expand Down
2 changes: 1 addition & 1 deletion Applet/src/com/android/javacard/keymaster/KMRepository.java
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Expand Up @@ -32,7 +32,7 @@
*/
public class KMRepository {

public static final short HEAP_SIZE = 15000;
public static final short HEAP_SIZE = 10000;

// Class Attributes
private byte[] heap;
Expand Down
4 changes: 2 additions & 2 deletions Applet/src/com/android/javacard/keymaster/RemotelyProvisionedComponentDevice.java
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Expand Up @@ -813,10 +813,10 @@ private KMDeviceUniqueKeyPair createDeviceUniqueKeyPair(boolean testMode, byte[]
(short) 128,
lengths);
deviceUniqueKeyPair =
storeDataInst.createTestDeviceUniqueKeyPair(scratchPad, (short) 128, lengths[1],
storeDataInst.createRkpTestDeviceUniqueKeyPair(scratchPad, (short) 128, lengths[1],
scratchPad, (short) 0, lengths[0]);
} else {
deviceUniqueKeyPair = storeDataInst.getDeviceUniqueKeyPair(false);
deviceUniqueKeyPair = storeDataInst.getRkpDeviceUniqueKeyPair(false);
}
return deviceUniqueKeyPair;
}
Expand Down
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