diff options
Diffstat (limited to 'src/java/com/android/internal/net/ipsec/ike/message/IkeMessage.java')
| -rw-r--r-- | src/java/com/android/internal/net/ipsec/ike/message/IkeMessage.java | 981 |
1 files changed, 0 insertions, 981 deletions
diff --git a/src/java/com/android/internal/net/ipsec/ike/message/IkeMessage.java b/src/java/com/android/internal/net/ipsec/ike/message/IkeMessage.java deleted file mode 100644 index 27fb9651..00000000 --- a/src/java/com/android/internal/net/ipsec/ike/message/IkeMessage.java +++ /dev/null @@ -1,981 +0,0 @@ -/* - * Copyright (C) 2018 The Android Open Source Project - * - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - */ - -package com.android.internal.net.ipsec.ike.message; - -import static android.net.ipsec.ike.IkeManager.getIkeLog; - -import static com.android.internal.net.ipsec.ike.message.IkePayload.PayloadType; - -import android.annotation.IntDef; -import android.annotation.Nullable; -import android.net.ipsec.ike.exceptions.IkeException; -import android.net.ipsec.ike.exceptions.IkeInternalException; -import android.net.ipsec.ike.exceptions.IkeProtocolException; -import android.util.Pair; - -import com.android.internal.annotations.VisibleForTesting; -import com.android.internal.net.ipsec.ike.SaRecord.IkeSaRecord; -import com.android.internal.net.ipsec.ike.crypto.IkeCipher; -import com.android.internal.net.ipsec.ike.crypto.IkeMacIntegrity; -import com.android.internal.net.ipsec.ike.exceptions.InvalidMessageIdException; -import com.android.internal.net.ipsec.ike.exceptions.InvalidSyntaxException; -import com.android.internal.net.ipsec.ike.exceptions.UnsupportedCriticalPayloadException; -import com.android.org.bouncycastle.jce.provider.BouncyCastleProvider; - -import java.lang.annotation.Retention; -import java.lang.annotation.RetentionPolicy; -import java.nio.BufferUnderflowException; -import java.nio.ByteBuffer; -import java.security.GeneralSecurityException; -import java.security.Provider; -import java.security.Security; -import java.util.Arrays; -import java.util.HashSet; -import java.util.LinkedList; -import java.util.List; -import java.util.Set; - -/** - * IkeMessage represents an IKE message. - * - * <p>It contains all attributes and provides methods for encoding, decoding, encrypting and - * decrypting. - * - * @see <a href="https://tools.ietf.org/html/rfc7296#section-3">RFC 7296, Internet Key Exchange - * Protocol Version 2 (IKEv2)</a> - */ -public final class IkeMessage { - private static final String TAG = "IkeMessage"; - - private static IIkeMessageHelper sIkeMessageHelper = new IkeMessageHelper(); - - // Currently use Bouncy Castle as crypto security provider - static final Provider SECURITY_PROVIDER = new BouncyCastleProvider(); - - // TODO: b/142070035 Use Conscrypt as default security provider instead of BC - - // Currently use HarmonyJSSE as TrustManager provider - static final Provider TRUST_MANAGER_PROVIDER = Security.getProvider("HarmonyJSSE"); - - // Payload types in this set may be included multiple times within an IKE message. All other - // payload types can be included at most once. - private static final Set<Integer> REPEATABLE_PAYLOAD_TYPES = new HashSet<>(); - - static { - REPEATABLE_PAYLOAD_TYPES.add(IkePayload.PAYLOAD_TYPE_CERT); - REPEATABLE_PAYLOAD_TYPES.add(IkePayload.PAYLOAD_TYPE_CERT_REQUEST); - REPEATABLE_PAYLOAD_TYPES.add(IkePayload.PAYLOAD_TYPE_NOTIFY); - REPEATABLE_PAYLOAD_TYPES.add(IkePayload.PAYLOAD_TYPE_DELETE); - REPEATABLE_PAYLOAD_TYPES.add(IkePayload.PAYLOAD_TYPE_VENDOR); - } - - public final IkeHeader ikeHeader; - public final List<IkePayload> ikePayloadList; - /** - * Conctruct an instance of IkeMessage. It is called by decode or for building outbound message. - * - * @param header the header of this IKE message - * @param payloadList the list of decoded IKE payloads in this IKE message - */ - public IkeMessage(IkeHeader header, List<IkePayload> payloadList) { - ikeHeader = header; - ikePayloadList = payloadList; - } - - /** - * Get security provider for IKE library - * - * <p>Use BouncyCastleProvider as the default security provider. - * - * @return the security provider of IKE library. - */ - public static Provider getSecurityProvider() { - // TODO: Move this getter out of IKE message package since not only this package uses it. - return SECURITY_PROVIDER; - } - - /** - * Get security provider for X509TrustManager to do certificate validation. - * - * <p>Use JSSEProvdier as the default security provider. - * - * @return the provider for X509TrustManager - */ - public static Provider getTrustManagerProvider() { - return TRUST_MANAGER_PROVIDER; - } - - /** - * Decode unencrypted IKE message body and create an instance of IkeMessage. - * - * <p>This method catches all RuntimeException during decoding incoming IKE packet. - * - * @param expectedMsgId the expected message ID to validate against. - * @param header the IKE header that is decoded but not validated. - * @param inputPacket the byte array contains the whole IKE message. - * @return the decoding result. - */ - public static DecodeResult decode(int expectedMsgId, IkeHeader header, byte[] inputPacket) { - return sIkeMessageHelper.decode(expectedMsgId, header, inputPacket); - } - - /** - * Decrypt and decode encrypted IKE message body and create an instance of IkeMessage. - * - * @param expectedMsgId the expected message ID to validate against. - * @param integrityMac the negotiated integrity algorithm. - * @param decryptCipher the negotiated encryption algorithm. - * @param ikeSaRecord ikeSaRecord where this packet is sent on. - * @param ikeHeader header of IKE packet. - * @param packet IKE packet as a byte array. - * @param collectedFragments previously received IKE fragments. - * @return the decoding result. - */ - public static DecodeResult decode( - int expectedMsgId, - @Nullable IkeMacIntegrity integrityMac, - IkeCipher decryptCipher, - IkeSaRecord ikeSaRecord, - IkeHeader ikeHeader, - byte[] packet, - DecodeResultPartial collectedFragments) { - return sIkeMessageHelper.decode( - expectedMsgId, - integrityMac, - decryptCipher, - ikeSaRecord, - ikeHeader, - packet, - collectedFragments); - } - - private static List<IkePayload> decodePayloadList( - @PayloadType int firstPayloadType, boolean isResp, byte[] unencryptedPayloads) - throws IkeProtocolException { - ByteBuffer inputBuffer = ByteBuffer.wrap(unencryptedPayloads); - int currentPayloadType = firstPayloadType; - // For supported payload - List<IkePayload> supportedPayloadList = new LinkedList<>(); - // For unsupported critical payload - List<Integer> unsupportedCriticalPayloadList = new LinkedList<>(); - - // For marking the existence of supported payloads in this message. - HashSet<Integer> supportedTypesFoundSet = new HashSet<>(); - - StringBuilder logPayloadsSb = new StringBuilder(); - logPayloadsSb.append("Decoded payloads [ "); - - while (currentPayloadType != IkePayload.PAYLOAD_TYPE_NO_NEXT) { - Pair<IkePayload, Integer> pair = - IkePayloadFactory.getIkePayload(currentPayloadType, isResp, inputBuffer); - IkePayload payload = pair.first; - logPayloadsSb.append(payload.getTypeString()).append(" "); - - if (!(payload instanceof IkeUnsupportedPayload)) { - int type = payload.payloadType; - if (!supportedTypesFoundSet.add(type) && !REPEATABLE_PAYLOAD_TYPES.contains(type)) { - throw new InvalidSyntaxException( - "It is not allowed to have multiple payloads with payload type: " - + type); - } - - supportedPayloadList.add(payload); - } else if (payload.isCritical) { - unsupportedCriticalPayloadList.add(payload.payloadType); - } - // Simply ignore unsupported uncritical payload. - - currentPayloadType = pair.second; - } - - logPayloadsSb.append("]"); - getIkeLog().d("IkeMessage", logPayloadsSb.toString()); - - if (inputBuffer.remaining() > 0) { - throw new InvalidSyntaxException( - "Malformed IKE Payload: Unexpected bytes at the end of packet."); - } - - if (unsupportedCriticalPayloadList.size() > 0) { - throw new UnsupportedCriticalPayloadException(unsupportedCriticalPayloadList); - } - - // TODO: Verify that for all status notification payloads, only - // NOTIFY_TYPE_NAT_DETECTION_SOURCE_IP and NOTIFY_TYPE_IPCOMP_SUPPORTED can be included - // multiple times in a request message. There is not a clear number restriction for - // error notification payloads. - - return supportedPayloadList; - } - - /** - * Encode unencrypted IKE message. - * - * @return encoded IKE message in byte array. - */ - public byte[] encode() { - return sIkeMessageHelper.encode(this); - } - - /** - * Encrypt and encode packet. - * - * @param integrityMac the negotiated integrity algorithm. - * @param encryptCipher the negotiated encryption algortihm. - * @param ikeSaRecord the ikeSaRecord where this packet is sent on. - * @param supportFragment if IKE fragmentation is supported - * @param fragSize the maximum size of IKE fragment - * @return encoded IKE message in byte array. - */ - public byte[][] encryptAndEncode( - @Nullable IkeMacIntegrity integrityMac, - IkeCipher encryptCipher, - IkeSaRecord ikeSaRecord, - boolean supportFragment, - int fragSize) { - return sIkeMessageHelper.encryptAndEncode( - integrityMac, encryptCipher, ikeSaRecord, this, supportFragment, fragSize); - } - - /** - * Encode all payloads to a byte array. - * - * @return byte array contains all encoded payloads - */ - private byte[] encodePayloads() { - StringBuilder logPayloadsSb = new StringBuilder(); - logPayloadsSb.append("Generating payloads [ "); - - int payloadLengthSum = 0; - for (IkePayload payload : ikePayloadList) { - payloadLengthSum += payload.getPayloadLength(); - logPayloadsSb.append(payload.getTypeString()).append(" "); - } - logPayloadsSb.append("]"); - getIkeLog().d("IkeMessage", logPayloadsSb.toString()); - - if (ikePayloadList.isEmpty()) return new byte[0]; - - ByteBuffer byteBuffer = ByteBuffer.allocate(payloadLengthSum); - for (int i = 0; i < ikePayloadList.size() - 1; i++) { - ikePayloadList - .get(i) - .encodeToByteBuffer(ikePayloadList.get(i + 1).payloadType, byteBuffer); - } - ikePayloadList - .get(ikePayloadList.size() - 1) - .encodeToByteBuffer(IkePayload.PAYLOAD_TYPE_NO_NEXT, byteBuffer); - - return byteBuffer.array(); - } - - /** Package */ - @VisibleForTesting - byte[] attachEncodedHeader(byte[] encodedIkeBody) { - ByteBuffer outputBuffer = - ByteBuffer.allocate(IkeHeader.IKE_HEADER_LENGTH + encodedIkeBody.length); - ikeHeader.encodeToByteBuffer(outputBuffer, encodedIkeBody.length); - outputBuffer.put(encodedIkeBody); - return outputBuffer.array(); - } - - /** - * Obtain all payloads with input payload type. - * - * <p>This method can be only applied to the payload types that can be included multiple times - * within an IKE message. - * - * @param payloadType the payloadType to look for. - * @param payloadClass the class of the desired payloads. - * @return a list of IkePayloads with the payloadType. - */ - public <T extends IkePayload> List<T> getPayloadListForType( - @IkePayload.PayloadType int payloadType, Class<T> payloadClass) { - // STOPSHIP: b/130190639 Notify user the error and close IKE session. - if (!REPEATABLE_PAYLOAD_TYPES.contains(payloadType)) { - throw new IllegalArgumentException( - "Received unexpected payloadType: " - + payloadType - + " that can be included at most once within an IKE message."); - } - - return IkePayload.getPayloadListForTypeInProvidedList( - payloadType, payloadClass, ikePayloadList); - } - - /** - * Obtain the payload with the input payload type. - * - * <p>This method can be only applied to the payload type that can be included at most once - * within an IKE message. - * - * @param payloadType the payloadType to look for. - * @param payloadClass the class of the desired payload. - * @return the IkePayload with the payloadType. - */ - public <T extends IkePayload> T getPayloadForType( - @IkePayload.PayloadType int payloadType, Class<T> payloadClass) { - // STOPSHIP: b/130190639 Notify user the error and close IKE session. - if (REPEATABLE_PAYLOAD_TYPES.contains(payloadType)) { - throw new IllegalArgumentException( - "Received unexpected payloadType: " - + payloadType - + " that may be included multiple times within an IKE message."); - } - - return IkePayload.getPayloadForTypeInProvidedList( - payloadType, payloadClass, ikePayloadList); - } - - /** - * Checks if this Request IkeMessage was a DPD message - * - * <p>An IKE message is a DPD request iff the message was encrypted (has a SK payload) and there - * were no payloads within the SK payload (or outside the SK payload). - */ - public boolean isDpdRequest() { - return !ikeHeader.isResponseMsg - && ikeHeader.exchangeType == IkeHeader.EXCHANGE_TYPE_INFORMATIONAL - && ikePayloadList.isEmpty() - && ikeHeader.nextPayloadType == IkePayload.PAYLOAD_TYPE_SK; - } - - /** - * IIkeMessageHelper provides interface for decoding, encoding and processing IKE packet. - * - * <p>IkeMessageHelper exists so that the interface is injectable for testing. - */ - @VisibleForTesting - public interface IIkeMessageHelper { - /** - * Encode IKE message. - * - * @param ikeMessage message need to be encoded. - * @return encoded IKE message in byte array. - */ - byte[] encode(IkeMessage ikeMessage); - - /** - * Encrypt and encode IKE message. - * - * @param integrityMac the negotiated integrity algorithm. - * @param encryptCipher the negotiated encryption algortihm. - * @param ikeSaRecord the ikeSaRecord where this packet is sent on. - * @param ikeMessage message need to be encoded. * @param supportFragment if IKE - * fragmentation is supported. - * @param fragSize the maximum size of IKE fragment. - * @return encoded IKE message in byte array. - */ - byte[][] encryptAndEncode( - @Nullable IkeMacIntegrity integrityMac, - IkeCipher encryptCipher, - IkeSaRecord ikeSaRecord, - IkeMessage ikeMessage, - boolean supportFragment, - int fragSize); - - // TODO: Return DecodeResult when decoding unencrypted message - /** - * Decode unencrypted packet. - * - * @param expectedMsgId the expected message ID to validate against. - * @param ikeHeader header of IKE packet. - * @param packet IKE packet as a byte array. - * @return the decoding result. - */ - DecodeResult decode(int expectedMsgId, IkeHeader ikeHeader, byte[] packet); - - /** - * Decrypt and decode packet. - * - * @param expectedMsgId the expected message ID to validate against. - * @param integrityMac the negotiated integrity algorithm. - * @param decryptCipher the negotiated encryption algorithm. - * @param ikeSaRecord ikeSaRecord where this packet is sent on. - * @param ikeHeader header of IKE packet. - * @param packet IKE packet as a byte array. - * @param collectedFragments previously received IKE fragments. - * @return the decoding result. - */ - DecodeResult decode( - int expectedMsgId, - @Nullable IkeMacIntegrity integrityMac, - IkeCipher decryptCipher, - IkeSaRecord ikeSaRecord, - IkeHeader ikeHeader, - byte[] packet, - DecodeResultPartial collectedFragments); - } - - /** IkeMessageHelper provides methods for decoding, encoding and processing IKE packet. */ - public static final class IkeMessageHelper implements IIkeMessageHelper { - @Override - public byte[] encode(IkeMessage ikeMessage) { - getIkeLog().d("IkeMessage", "Generating " + ikeMessage.ikeHeader.getBasicInfoString()); - - byte[] encodedIkeBody = ikeMessage.encodePayloads(); - byte[] packet = ikeMessage.attachEncodedHeader(encodedIkeBody); - getIkeLog().d("IkeMessage", "Build a complete IKE message: " + getIkeLog().pii(packet)); - return packet; - } - - @Override - public byte[][] encryptAndEncode( - @Nullable IkeMacIntegrity integrityMac, - IkeCipher encryptCipher, - IkeSaRecord ikeSaRecord, - IkeMessage ikeMessage, - boolean supportFragment, - int fragSize) { - getIkeLog().d("IkeMessage", "Generating " + ikeMessage.ikeHeader.getBasicInfoString()); - - return encryptAndEncode( - ikeMessage.ikeHeader, - ikeMessage.ikePayloadList.isEmpty() - ? IkePayload.PAYLOAD_TYPE_NO_NEXT - : ikeMessage.ikePayloadList.get(0).payloadType, - ikeMessage.encodePayloads(), - integrityMac, - encryptCipher, - ikeSaRecord.getOutboundIntegrityKey(), - ikeSaRecord.getOutboundEncryptionKey(), - supportFragment, - fragSize); - } - - @VisibleForTesting - byte[][] encryptAndEncode( - IkeHeader ikeHeader, - @PayloadType int firstInnerPayload, - byte[] unencryptedPayloads, - @Nullable IkeMacIntegrity integrityMac, - IkeCipher encryptCipher, - byte[] integrityKey, - byte[] encryptionKey, - boolean supportFragment, - int fragSize) { - - IkeSkPayload skPayload = - new IkeSkPayload( - ikeHeader, - firstInnerPayload, - unencryptedPayloads, - integrityMac, - encryptCipher, - integrityKey, - encryptionKey); - int msgLen = IkeHeader.IKE_HEADER_LENGTH + skPayload.getPayloadLength(); - - // Build complete IKE message - if (!supportFragment || msgLen <= fragSize) { - byte[][] packetList = new byte[1][]; - packetList[0] = encodeHeaderAndBody(ikeHeader, skPayload, firstInnerPayload); - - getIkeLog() - .d( - "IkeMessage", - "Build a complete IKE message: " + getIkeLog().pii(packetList[0])); - return packetList; - } - - // Build IKE fragments - int dataLenPerPacket = - fragSize - - IkeHeader.IKE_HEADER_LENGTH - - IkePayload.GENERIC_HEADER_LENGTH - - IkeSkfPayload.SKF_HEADER_LEN - - encryptCipher.getIvLen() - - integrityMac.getChecksumLen() - - encryptCipher.getBlockSize(); - - // Caller of this method MUST validate fragSize is valid. - if (dataLenPerPacket <= 0) { - throw new IllegalArgumentException( - "Max fragment size is too small for an IKE fragment."); - } - - int totalFragments = - (unencryptedPayloads.length + dataLenPerPacket - 1) / dataLenPerPacket; - IkeHeader skfHeader = ikeHeader.makeSkfHeaderFromSkHeader(); - byte[][] packetList = new byte[totalFragments][]; - - ByteBuffer unencryptedDataBuffer = ByteBuffer.wrap(unencryptedPayloads); - for (int i = 0; i < totalFragments; i++) { - byte[] unencryptedData = - new byte[Math.min(dataLenPerPacket, unencryptedDataBuffer.remaining())]; - unencryptedDataBuffer.get(unencryptedData); - - int fragNum = i + 1; // 1-based - - IkeSkfPayload skfPayload = - new IkeSkfPayload( - ikeHeader, - firstInnerPayload, - unencryptedData, - integrityMac, - encryptCipher, - integrityKey, - encryptionKey, - fragNum, - totalFragments); - - packetList[i] = - encodeHeaderAndBody( - skfHeader, - skfPayload, - i == 0 ? firstInnerPayload : IkePayload.PAYLOAD_TYPE_NO_NEXT); - getIkeLog() - .d( - "IkeMessage", - "Build an IKE fragment (" - + (i + 1) - + "/" - + totalFragments - + "): " - + getIkeLog().pii(packetList[0])); - } - - return packetList; - } - - private byte[] encodeHeaderAndBody( - IkeHeader ikeHeader, IkeSkPayload skPayload, @PayloadType int firstInnerPayload) { - ByteBuffer outputBuffer = - ByteBuffer.allocate(IkeHeader.IKE_HEADER_LENGTH + skPayload.getPayloadLength()); - ikeHeader.encodeToByteBuffer(outputBuffer, skPayload.getPayloadLength()); - skPayload.encodeToByteBuffer(firstInnerPayload, outputBuffer); - return outputBuffer.array(); - } - - @Override - public DecodeResult decode(int expectedMsgId, IkeHeader header, byte[] inputPacket) { - try { - if (header.messageId != expectedMsgId) { - throw new InvalidMessageIdException(header.messageId); - } - - header.validateMajorVersion(); - header.validateInboundHeader(inputPacket.length); - - byte[] unencryptedPayloads = - Arrays.copyOfRange( - inputPacket, IkeHeader.IKE_HEADER_LENGTH, inputPacket.length); - List<IkePayload> supportedPayloadList = - decodePayloadList( - header.nextPayloadType, header.isResponseMsg, unencryptedPayloads); - return new DecodeResultOk( - new IkeMessage(header, supportedPayloadList), inputPacket); - } catch (NegativeArraySizeException | BufferUnderflowException e) { - // Invalid length error when parsing payload bodies. - return new DecodeResultUnprotectedError( - new InvalidSyntaxException("Malformed IKE Payload")); - } catch (IkeProtocolException e) { - return new DecodeResultUnprotectedError(e); - } - } - - @Override - public DecodeResult decode( - int expectedMsgId, - @Nullable IkeMacIntegrity integrityMac, - IkeCipher decryptCipher, - IkeSaRecord ikeSaRecord, - IkeHeader ikeHeader, - byte[] packet, - DecodeResultPartial collectedFragments) { - return decode( - expectedMsgId, - ikeHeader, - packet, - integrityMac, - decryptCipher, - ikeSaRecord.getInboundIntegrityKey(), - ikeSaRecord.getInboundDecryptionKey(), - collectedFragments); - } - - private DecodeResult decode( - int expectedMsgId, - IkeHeader header, - byte[] inputPacket, - @Nullable IkeMacIntegrity integrityMac, - IkeCipher decryptCipher, - byte[] integrityKey, - byte[] decryptionKey, - DecodeResultPartial collectedFragments) { - if (header.nextPayloadType != IkePayload.PAYLOAD_TYPE_SK - && header.nextPayloadType != IkePayload.PAYLOAD_TYPE_SKF) { - // TODO: b/123372339 Handle message containing unprotected payloads. - throw new UnsupportedOperationException("Message contains unprotected payloads"); - } - - // Decrypt message and do authentication - Pair<IkeSkPayload, Integer> pair; - try { - pair = - decryptAndAuthenticate( - expectedMsgId, - header, - inputPacket, - integrityMac, - decryptCipher, - integrityKey, - decryptionKey); - } catch (IkeException e) { - if (collectedFragments == null) { - return new DecodeResultUnprotectedError(e); - } else { - getIkeLog() - .i( - TAG, - "Message authentication or decryption failed on received" - + " message. Discard it ", - e); - return collectedFragments; - } - } - - // Handle IKE fragment - boolean isFragment = (header.nextPayloadType == IkePayload.PAYLOAD_TYPE_SKF); - boolean fragReassemblyStarted = (collectedFragments != null); - - if (isFragment) { - getIkeLog() - .d( - TAG, - "Received an IKE fragment (" - + ((IkeSkfPayload) pair.first).fragmentNum - + "/" - + ((IkeSkfPayload) pair.first).totalFragments - + ")"); - } - - // IKE fragment reassembly has started but a complete message was received. - if (!isFragment && fragReassemblyStarted) { - getIkeLog() - .w( - TAG, - "Received a complete IKE message while doing IKE fragment" - + " reassembly. Discard the newly received message."); - return collectedFragments; - } - - byte[] firstPacket = inputPacket; - byte[] decryptedBytes = pair.first.getUnencryptedData(); - int firstPayloadType = pair.second; - - // Received an IKE fragment - if (isFragment) { - validateFragmentHeader(header, inputPacket.length, collectedFragments); - - // Add the recently received fragment to the reassembly queue. - DecodeResultPartial DecodeResultPartial = - processIkeFragment( - header, - inputPacket, - (IkeSkfPayload) (pair.first), - pair.second, - collectedFragments); - - if (!DecodeResultPartial.isAllFragmentsReceived()) return DecodeResultPartial; - - firstPayloadType = DecodeResultPartial.firstPayloadType; - decryptedBytes = DecodeResultPartial.reassembleAllFrags(); - firstPacket = DecodeResultPartial.firstFragBytes; - } - - // Received or has reassembled a complete IKE message. Check if there is protocol error. - try { - // TODO: Log IKE header information and payload types - - List<IkePayload> supportedPayloadList = - decodePayloadList(firstPayloadType, header.isResponseMsg, decryptedBytes); - - header.validateInboundHeader(inputPacket.length); - return new DecodeResultOk( - new IkeMessage(header, supportedPayloadList), firstPacket); - } catch (NegativeArraySizeException | BufferUnderflowException e) { - // Invalid length error when parsing payload bodies. - return new DecodeResultProtectedError( - new InvalidSyntaxException("Malformed IKE Payload", e), firstPacket); - } catch (IkeProtocolException e) { - return new DecodeResultProtectedError(e, firstPacket); - } - } - - private Pair<IkeSkPayload, Integer> decryptAndAuthenticate( - int expectedMsgId, - IkeHeader header, - byte[] inputPacket, - @Nullable IkeMacIntegrity integrityMac, - IkeCipher decryptCipher, - byte[] integrityKey, - byte[] decryptionKey) - throws IkeException { - - try { - if (header.messageId != expectedMsgId) { - throw new InvalidMessageIdException(header.messageId); - } - - header.validateMajorVersion(); - - boolean isSkf = header.nextPayloadType == IkePayload.PAYLOAD_TYPE_SKF; - return IkePayloadFactory.getIkeSkPayload( - isSkf, - inputPacket, - integrityMac, - decryptCipher, - integrityKey, - decryptionKey); - } catch (NegativeArraySizeException | BufferUnderflowException e) { - throw new InvalidSyntaxException("Malformed IKE Payload", e); - } catch (GeneralSecurityException e) { - throw new IkeInternalException(e); - } - } - - private void validateFragmentHeader( - IkeHeader fragIkeHeader, int packetLen, DecodeResultPartial collectedFragments) { - try { - fragIkeHeader.validateInboundHeader(packetLen); - } catch (IkeProtocolException e) { - getIkeLog() - .e( - TAG, - "Received an IKE fragment with invalid header. Will be handled when" - + " reassembly is done.", - e); - } - - if (collectedFragments == null) return; - if (fragIkeHeader.exchangeType != collectedFragments.ikeHeader.exchangeType) { - getIkeLog() - .e( - TAG, - "Received an IKE fragment with different exchange type from" - + " previously collected fragments. Ignore it."); - } - } - - private DecodeResultPartial processIkeFragment( - IkeHeader header, - byte[] inputPacket, - IkeSkfPayload skf, - int nextPayloadType, - @Nullable DecodeResultPartial collectedFragments) { - if (collectedFragments == null) { - return new DecodeResultPartial( - header, inputPacket, skf, nextPayloadType, collectedFragments); - } - - if (skf.totalFragments > collectedFragments.collectedFragsList.length) { - getIkeLog() - .i( - TAG, - "Received IKE fragment has larger total fragments number. Discard" - + " all previously collected fragments"); - return new DecodeResultPartial( - header, inputPacket, skf, nextPayloadType, null /*collectedFragments*/); - } - - if (skf.totalFragments < collectedFragments.collectedFragsList.length) { - getIkeLog() - .i( - TAG, - "Received IKE fragment has smaller total fragments number. Discard" - + " it."); - return collectedFragments; - } - - if (collectedFragments.collectedFragsList[skf.fragmentNum - 1] != null) { - getIkeLog().i(TAG, "Received IKE fragment is a replay."); - return collectedFragments; - } - - return new DecodeResultPartial( - header, inputPacket, skf, nextPayloadType, collectedFragments); - } - } - - /** Status to describe the result of decoding an inbound IKE message. */ - @Retention(RetentionPolicy.SOURCE) - @IntDef({ - DECODE_STATUS_OK, - DECODE_STATUS_PARTIAL, - DECODE_STATUS_PROTECTED_ERROR, - DECODE_STATUS_UNPROTECTED_ERROR, - }) - public @interface DecodeStatus {} - - /** - * Represents a message that has been successfully (decrypted and) decoded or reassembled from - * IKE fragments - */ - public static final int DECODE_STATUS_OK = 0; - /** Represents that reassembly process of IKE fragments has started but has not finished */ - public static final int DECODE_STATUS_PARTIAL = 1; - /** Represents a crypto protected message with correct message ID but has parsing error. */ - public static final int DECODE_STATUS_PROTECTED_ERROR = 2; - /** - * Represents an unencrypted message with parsing error, an encrypted message with - * authentication or decryption error, or any message with wrong message ID. - */ - public static final int DECODE_STATUS_UNPROTECTED_ERROR = 3; - - /** This class represents common decoding result of an IKE message. */ - public abstract static class DecodeResult { - public final int status; - - /** Construct an instance of DecodeResult. */ - protected DecodeResult(int status) { - this.status = status; - } - } - - /** This class represents an IKE message has been successfully (decrypted and) decoded. */ - public static class DecodeResultOk extends DecodeResult { - public final IkeMessage ikeMessage; - public final byte[] firstPacket; - - public DecodeResultOk(IkeMessage ikeMessage, byte[] firstPacket) { - super(DECODE_STATUS_OK); - this.ikeMessage = ikeMessage; - this.firstPacket = firstPacket; - } - } - - /** - * This class represents IKE fragments are being reassembled to build a complete IKE message. - * - * <p>All IKE fragments should have the same IKE headers, except for the message length. This - * class only stores the IKE header of the first arrived IKE fragment to represent the IKE - * header of the complete IKE message. In this way we can verify all subsequent fragments' - * headers against it. - * - * <p>The first payload type is only stored in the first fragment, as indicated in RFC 7383. So - * this class only stores the next payload type field taken from the first fragment. - */ - public static class DecodeResultPartial extends DecodeResult { - public final int firstPayloadType; - public final byte[] firstFragBytes; - public final IkeHeader ikeHeader; - public final byte[][] collectedFragsList; - - /** - * Construct an instance of DecodeResultPartial with collected fragments and the newly - * received fragment. - * - * <p>The newly received fragment has been validated against collected fragments during - * decoding that all fragments have the same total fragments number and the newly received - * fragment is not a replay. - */ - public DecodeResultPartial( - IkeHeader ikeHeader, - byte[] inputPacket, - IkeSkfPayload skfPayload, - int nextPayloadType, - @Nullable DecodeResultPartial collectedFragments) { - super(DECODE_STATUS_PARTIAL); - - boolean isFirstFragment = 1 == skfPayload.fragmentNum; - if (collectedFragments == null) { - // First arrived IKE fragment - this.ikeHeader = ikeHeader; - this.firstPayloadType = - isFirstFragment ? nextPayloadType : IkePayload.PAYLOAD_TYPE_NO_NEXT; - this.firstFragBytes = isFirstFragment ? inputPacket : null; - this.collectedFragsList = new byte[skfPayload.totalFragments][]; - } else { - this.ikeHeader = collectedFragments.ikeHeader; - this.firstPayloadType = - isFirstFragment ? nextPayloadType : collectedFragments.firstPayloadType; - this.firstFragBytes = - isFirstFragment ? inputPacket : collectedFragments.firstFragBytes; - this.collectedFragsList = collectedFragments.collectedFragsList; - } - - this.collectedFragsList[skfPayload.fragmentNum - 1] = skfPayload.getUnencryptedData(); - } - - /** Return if all IKE fragments have been collected */ - public boolean isAllFragmentsReceived() { - for (byte[] frag : collectedFragsList) { - if (frag == null) return false; - } - return true; - } - - /** Reassemble all IKE fragments and return the unencrypted message body in byte array. */ - public byte[] reassembleAllFrags() { - if (!isAllFragmentsReceived()) { - throw new IllegalStateException("Not all fragments have been received"); - } - - int len = 0; - for (byte[] frag : collectedFragsList) { - len += frag.length; - } - - ByteBuffer buffer = ByteBuffer.allocate(len); - for (byte[] frag : collectedFragsList) { - buffer.put(frag); - } - - return buffer.array(); - } - } - - /** - * This class represents common information of error cases in decrypting and decoding message. - */ - public abstract static class DecodeResultError extends DecodeResult { - public final IkeException ikeException; - - protected DecodeResultError(int status, IkeException ikeException) { - super(status); - this.ikeException = ikeException; - } - } - /** - * This class represents that decoding errors have been found after the IKE message is - * authenticated and decrypted. - */ - public static class DecodeResultProtectedError extends DecodeResultError { - public final byte[] firstPacket; - - public DecodeResultProtectedError(IkeException ikeException, byte[] firstPacket) { - super(DECODE_STATUS_PROTECTED_ERROR, ikeException); - this.firstPacket = firstPacket; - } - } - /** This class represents errors have been found during message authentication or decryption. */ - public static class DecodeResultUnprotectedError extends DecodeResultError { - public DecodeResultUnprotectedError(IkeException ikeException) { - super(DECODE_STATUS_UNPROTECTED_ERROR, ikeException); - } - } - - /** - * For setting mocked IIkeMessageHelper for testing - * - * @param helper the mocked IIkeMessageHelper - */ - public static void setIkeMessageHelper(IIkeMessageHelper helper) { - sIkeMessageHelper = helper; - } -} |