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Merged
AvinashHedage merged 9 commits into from
Apr 13, 2022
Merged

Hmac sign len validation #2

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c1e9e6f
Merge pull request #46 from AvinashHedage/hmac_sign_len_validation
subrahmanyaman Apr 12, 2022
3b55e2d
Fixed compilation erros
subrahmanyaman Apr 12, 2022
1d3bf38
Merge pull request #47 from subrahmanyaman/import_key_changes
subrahmanyaman Apr 12, 2022
7a3760c
Addressed review comments
subrahmanyaman Apr 12, 2022
d24f008
Merge pull request #48 from subrahmanyaman/import_key_changes
subrahmanyaman Apr 12, 2022
2e36786
1. In processAttestKey , call isKeyUpgradeRequired() for generated k…
subrahmanyaman Apr 13, 2022
b0061fc
Merge pull request #111 from subrahmanyaman/import_key_changes
mdwivedi Apr 13, 2022
efc9f41
Merge pull request #49 from subrahmanyaman/import_key_changes
subrahmanyaman Apr 13, 2022
21449c0
Merge pull request #50 from divegeek/Javacard_KeyMint_100_master
subrahmanyaman Apr 13, 2022
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4 changes: 2 additions & 2 deletions Applet/src/com/android/javacard/keymaster/KMEncoder.java
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Original file line numberDiff line numberDiff line change
Expand Up@@ -82,8 +82,8 @@ public short encode(short object, byte[] buffer, short startOff) {
bufferRef[0] = buffer;
scratchBuf[START_OFFSET] = startOff;
short len = (short) (buffer.length - startOff);
if ((len < 0) || len > KMKeymasterApplet.MAX_LENGTH) {
scratchBuf[LEN_OFFSET] = KMKeymasterApplet.MAX_LENGTH;
if ((len < 0) || len > KMRepository.HEAP_SIZE) {
scratchBuf[LEN_OFFSET] = KMRepository.HEAP_SIZE;
} else {
scratchBuf[LEN_OFFSET] = (short) buffer.length;
}
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1 change: 1 addition & 0 deletions Applet/src/com/android/javacard/keymaster/KMError.java
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Expand Up@@ -45,6 +45,7 @@ public class KMError {

public static final short KEY_USER_NOT_AUTHENTICATED = 26;
public static final short INVALID_OPERATION_HANDLE = 28;
public static final short INSUFFICIENT_BUFFER_SPACE = 29;
public static final short VERIFICATION_FAILED = 30;
public static final short TOO_MANY_OPERATIONS = 31;
public static final short INVALID_KEY_BLOB = 33;
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33 changes: 23 additions & 10 deletions Applet/src/com/android/javacard/keymaster/KMKeymasterApplet.java
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Expand Up@@ -41,7 +41,6 @@ public class KMKeymasterApplet extends Applet implements AppletEvent, ExtendedLe
public static final byte[] F4 = {0x01, 0x00, 0x01};
public static final byte AES_BLOCK_SIZE = 16;
public static final byte DES_BLOCK_SIZE = 8;
public static final short MAX_LENGTH = 10000;
public static final short MASTER_KEY_SIZE = 128;
public static final short WRAPPING_KEY_SIZE = 32;
public static final short MAX_OPERATIONS_COUNT = 4;
Expand DownExpand Up@@ -106,8 +105,9 @@ public class KMKeymasterApplet extends Applet implements AppletEvent, ExtendedLe
};

public static final short MAX_COSE_BUF_SIZE = (short) 1024;
// Maximum possible encoded keyparams size
public static final short MAX_KEY_PARAMS_BUF_SIZE = (short) 2048;
// Maximum allowed buffer size for to encode the key parameters
// which is used while creating mac for key paramters.
public static final short MAX_KEY_PARAMS_BUF_SIZE = (short) 3072; // 3K
// Top 32 commands are reserved for provisioning.
private static final byte KEYMINT_CMD_APDU_START = 0x20;

Expand DownExpand Up@@ -3506,8 +3506,13 @@ private void processAttestKeyCmd(APDU apdu) {
data[APP_DATA] = getApplicationData(data[KEY_PARAMETERS]);
// Check if key requires upgrade. The KeyBlob is parsed inside isKeyUpgradeRequired
// function itself.
parseEncryptedKeyBlob(data[KEY_BLOB], data[APP_ID], data[APP_DATA], scratchPad,
KEYBLOB_CURRENT_VERSION);
if (isKeyUpgradeRequired(data[KEY_BLOB], data[APP_ID], data[APP_DATA], scratchPad)) {
// This condition occurs if either any of the system properties (OsVersion, OsPatchLevel,
// VendorPatchLevel or BootPatchLevel) changes or KeyBlob format changed. So return
// KEY_REQUIRES_UPGRADE error as this scenario is application to ATTEST_KEY_BLOB as well
// as ATTEST_KEY_BLOB got generated before the KEY_BLOB.
KMException.throwIt(KMError.KEY_REQUIRES_UPGRADE);
}
// Validate KeyParams Mac
if (!validateKeyParamsMac(data[KEY_PARAMETERS], keyParamsMac, scratchPad)) {
KMException.throwIt(KMError.INVALID_KEY_BLOB);
Expand DownExpand Up@@ -3801,18 +3806,26 @@ private short macKeyParams(short keyParams, byte[] scratchPad) {
if (SYM_KEY_TYPE == getKeyType(keyParams)) {
return KMByteBlob.instance((short) 0);
}
short len = encodeToApduBuffer(keyParams, scratchPad, (short) 0, MAX_KEY_PARAMS_BUF_SIZE);
short offset = repository.allocReclaimableMemory(MAX_KEY_PARAMS_BUF_SIZE);
short len = encoder.encode(keyParams, repository.getHeap(), offset);
if (len > MAX_KEY_PARAMS_BUF_SIZE) {
// KeyParamters exceeded the maximum allowed size.
KMException.throwIt(KMError.INSUFFICIENT_BUFFER_SPACE);
}

short signLen = seProvider.hmacSign(
KMByteBlob.cast(data[AUTH_TAG]).getBuffer(),
KMByteBlob.cast(data[AUTH_TAG]).getStartOff(),
KMByteBlob.cast(data[AUTH_TAG]).length(),
scratchPad,
(short) 0,
repository.getHeap(),
offset,
len,
scratchPad,
len);
return KMByteBlob.instance(scratchPad, len, signLen);
(short) 0);
//release memory
repository.reclaimMemory(MAX_KEY_PARAMS_BUF_SIZE);

return KMByteBlob.instance(scratchPad, (short) 0, signLen);
}

private boolean validateKeyParamsMac(short keyParams, short keyParamsMac, byte[] scratchPad) {
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14 changes: 7 additions & 7 deletions HAL/JavacardKeyMintDevice.cpp
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Original file line numberDiff line numberDiff line change
Expand Up@@ -93,20 +93,20 @@ ScopedAStatus JavacardKeyMintDevice::generateKey(const vector<KeyParameter>& key
// Call attestKey only Asymmetric algorithms.
keymaster_algorithm_t algorithm;
paramSet.GetTagValue(TAG_ALGORITHM, &algorithm);
if (algorithm == KM_ALGORITHM_RSA || algorithm == KM_ALGORITHM_EC) {
if (algorithm == KM_ALGORITHM_RSA || algorithm == KM_ALGORITHM_EC) {
cppbor::Array attestKeyArray;
attestKeyArray.add(creationResult->keyBlob);
cbor_.addKeyparameters(attestKeyArray, keyParams);
cbor_.addAttestationKey(attestKeyArray, attestationKey);
attestKeyArray.add(keyParamsMac);
auto [certItem, error] = card_->sendRequest(Instruction::INS_ATTEST_KEY_CMD, attestKeyArray);
if (error != KM_ERROR_OK) {
LOG(ERROR) << "Failed in attestKey err: ";
return km_utils::kmError2ScopedAStatus(error);
LOG(ERROR) << "Failed in attestKey err: " << error;
return km_utils::kmError2ScopedAStatus(error);
}
if (!cbor_.getCertificateChain(certItem, 1, creationResult->certificateChain)) {
LOG(ERROR) << "Error in decoding og response in generateKey.";
return km_utils::kmError2ScopedAStatus(KM_ERROR_UNKNOWN_ERROR);
LOG(ERROR) << "Error in decoding og response in generateKey.";
return km_utils::kmError2ScopedAStatus(KM_ERROR_UNKNOWN_ERROR);
}
}
return ScopedAStatus::ok();
Expand DownExpand Up@@ -163,7 +163,7 @@ ScopedAStatus JavacardKeyMintDevice::importKey(const vector<KeyParameter>& keyPa
attestKeyArray.add(keyParamsMac);
auto [certItem, error] = card_->sendRequest(Instruction::INS_ATTEST_KEY_CMD, attestKeyArray);
if (error != KM_ERROR_OK) {
LOG(ERROR) << "Failed in attestKey err: ";
LOG(ERROR) << "Failed in attestKey err: " << error;
return km_utils::kmError2ScopedAStatus(error);
}
if (!cbor_.getCertificateChain(certItem, 1, creationResult->certificateChain)) {
Expand DownExpand Up@@ -235,7 +235,7 @@ ScopedAStatus JavacardKeyMintDevice::importWrappedKey(const vector<uint8_t>& wra
cbor_.addAttestationKey(attestKeyArray, std::nullopt);
auto [certItem, error] = card_->sendRequest(Instruction::INS_ATTEST_KEY_CMD, attestKeyArray);
if (error != KM_ERROR_OK) {
LOG(ERROR) << "Failed in attestKey err: ";
LOG(ERROR) << "Failed in attestKey err: " << error;
return km_utils::kmError2ScopedAStatus(error);
}
if (!cbor_.getCertificateChain(certItem, 1, creationResult->certificateChain)) {
Expand Down