private static void decodeSelectors(Interest interest, TlvDecoder decoder,
bool copy)
{
int endOffset = decoder.readNestedTlvsStart(net.named_data.jndn.encoding.tlv.Tlv.Selectors);
interest.setMinSuffixComponents((int) decoder
.readOptionalNonNegativeIntegerTlv(net.named_data.jndn.encoding.tlv.Tlv.MinSuffixComponents,
endOffset));
interest.setMaxSuffixComponents((int) decoder
.readOptionalNonNegativeIntegerTlv(net.named_data.jndn.encoding.tlv.Tlv.MaxSuffixComponents,
endOffset));
if (decoder.peekType(net.named_data.jndn.encoding.tlv.Tlv.PublisherPublicKeyLocator, endOffset))
decodeKeyLocator(net.named_data.jndn.encoding.tlv.Tlv.PublisherPublicKeyLocator,
interest.getKeyLocator(), decoder, copy);
else
interest.getKeyLocator().clear();
if (decoder.peekType(net.named_data.jndn.encoding.tlv.Tlv.Exclude, endOffset))
decodeExclude(interest.getExclude(), decoder, copy);
else
interest.getExclude().clear();
interest.setChildSelector((int) decoder
.readOptionalNonNegativeIntegerTlv(net.named_data.jndn.encoding.tlv.Tlv.ChildSelector, endOffset));
interest.setMustBeFresh(decoder.readBooleanTlv(net.named_data.jndn.encoding.tlv.Tlv.MustBeFresh,
endOffset));
decoder.finishNestedTlvs(endOffset);
}
private static void decodeMetaInfo(MetaInfo metaInfo, TlvDecoder decoder,
bool copy)
{
int endOffset = decoder.readNestedTlvsStart(net.named_data.jndn.encoding.tlv.Tlv.MetaInfo);
// The ContentType enum is set up with the correct integer for each
// NDN-TLV ContentType.
int type = (int) decoder.readOptionalNonNegativeIntegerTlv(
net.named_data.jndn.encoding.tlv.Tlv.ContentType, endOffset);
if (type < 0 || type == net.named_data.jndn.ContentType.BLOB.getNumericType())
// Default to BLOB if the value is omitted.
metaInfo.setType(net.named_data.jndn.ContentType.BLOB);
else if (type == net.named_data.jndn.ContentType.LINK.getNumericType())
metaInfo.setType(net.named_data.jndn.ContentType.LINK);
else if (type == net.named_data.jndn.ContentType.KEY.getNumericType())
metaInfo.setType(net.named_data.jndn.ContentType.KEY);
else if (type == net.named_data.jndn.ContentType.NACK.getNumericType())
metaInfo.setType(net.named_data.jndn.ContentType.NACK);
else {
// Unrecognized content type.
metaInfo.setType(net.named_data.jndn.ContentType.OTHER_CODE);
metaInfo.setOtherTypeCode(type);
}
metaInfo.setFreshnessPeriod(decoder.readOptionalNonNegativeIntegerTlv(
net.named_data.jndn.encoding.tlv.Tlv.FreshnessPeriod, endOffset));
if (decoder.peekType(net.named_data.jndn.encoding.tlv.Tlv.FinalBlockId, endOffset)) {
int finalBlockIdEndOffset = decoder
.readNestedTlvsStart(net.named_data.jndn.encoding.tlv.Tlv.FinalBlockId);
metaInfo.setFinalBlockId(decodeNameComponent(decoder, copy));
decoder.finishNestedTlvs(finalBlockIdEndOffset);
} else
metaInfo.setFinalBlockId(null);
decoder.finishNestedTlvs(endOffset);
}
/// <summary>
/// Decode input as an NDN-TLV LpPacket and set the fields of the lpPacket object.
/// </summary>
///
/// <param name="lpPacket">The LpPacket object whose fields are updated.</param>
/// <param name="input"></param>
/// <param name="copy">unchanged while the Blob values are used.</param>
/// <exception cref="EncodingException">For invalid encoding.</exception>
public override void decodeLpPacket(LpPacket lpPacket, ByteBuffer input, bool copy)
{
lpPacket.clear();
TlvDecoder decoder = new TlvDecoder(input);
int endOffset = decoder.readNestedTlvsStart(net.named_data.jndn.encoding.tlv.Tlv.LpPacket_LpPacket);
while (decoder.getOffset() < endOffset) {
// Imitate TlvDecoder.readTypeAndLength.
int fieldType = decoder.readVarNumber();
int fieldLength = decoder.readVarNumber();
int fieldEndOffset = decoder.getOffset() + fieldLength;
if (fieldEndOffset > input.limit())
throw new EncodingException(
"TLV length exceeds the buffer length");
if (fieldType == net.named_data.jndn.encoding.tlv.Tlv.LpPacket_Fragment) {
// Set the fragment to the bytes of the TLV value.
lpPacket.setFragmentWireEncoding(new Blob(decoder.getSlice(
decoder.getOffset(), fieldEndOffset), copy));
decoder.seek(fieldEndOffset);
// The fragment is supposed to be the last field.
break;
} else if (fieldType == net.named_data.jndn.encoding.tlv.Tlv.LpPacket_Nack) {
NetworkNack networkNack = new NetworkNack();
int code = (int) decoder.readOptionalNonNegativeIntegerTlv(
net.named_data.jndn.encoding.tlv.Tlv.LpPacket_NackReason, fieldEndOffset);
// The enum numeric values are the same as this wire format, so use as is.
if (code < 0
|| code == net.named_data.jndn.NetworkNack.Reason.NONE.getNumericType())
// This includes an omitted NackReason.
networkNack.setReason(net.named_data.jndn.NetworkNack.Reason.NONE);
else if (code == net.named_data.jndn.NetworkNack.Reason.CONGESTION.getNumericType())
networkNack.setReason(net.named_data.jndn.NetworkNack.Reason.CONGESTION);
else if (code == net.named_data.jndn.NetworkNack.Reason.DUPLICATE.getNumericType())
networkNack.setReason(net.named_data.jndn.NetworkNack.Reason.DUPLICATE);
else if (code == net.named_data.jndn.NetworkNack.Reason.NO_ROUTE.getNumericType())
networkNack.setReason(net.named_data.jndn.NetworkNack.Reason.NO_ROUTE);
else {
// Unrecognized reason.
networkNack.setReason(net.named_data.jndn.NetworkNack.Reason.OTHER_CODE);
networkNack.setOtherReasonCode(code);
}
lpPacket.addHeaderField(networkNack);
} else if (fieldType == net.named_data.jndn.encoding.tlv.Tlv.LpPacket_IncomingFaceId) {
IncomingFaceId incomingFaceId = new IncomingFaceId();
incomingFaceId.setFaceId(decoder
.readNonNegativeInteger(fieldLength));
lpPacket.addHeaderField(incomingFaceId);
} else {
// Unrecognized field type. The conditions for ignoring are here:
// http://redmine.named-data.net/projects/nfd/wiki/NDNLPv2
bool canIgnore = (fieldType >= net.named_data.jndn.encoding.tlv.Tlv.LpPacket_IGNORE_MIN
&& fieldType <= net.named_data.jndn.encoding.tlv.Tlv.LpPacket_IGNORE_MAX && (fieldType & 0x01) == 1);
if (!canIgnore)
throw new EncodingException(
"Did not get the expected TLV type");
// Ignore.
decoder.seek(fieldEndOffset);
}
decoder.finishNestedTlvs(fieldEndOffset);
}
decoder.finishNestedTlvs(endOffset);
}
private static void decodeControlParameters(
ControlParameters controlParameters, TlvDecoder decoder,
bool copy)
{
controlParameters.clear();
int endOffset = decoder
.readNestedTlvsStart(net.named_data.jndn.encoding.tlv.Tlv.ControlParameters_ControlParameters);
// decode name
if (decoder.peekType(net.named_data.jndn.encoding.tlv.Tlv.Name, endOffset)) {
Name name = new Name();
decodeName(name, new int[1], new int[1], decoder, copy);
controlParameters.setName(name);
}
// decode face ID
controlParameters.setFaceId((int) decoder
.readOptionalNonNegativeIntegerTlv(
net.named_data.jndn.encoding.tlv.Tlv.ControlParameters_FaceId, endOffset));
// decode URI
if (decoder.peekType(net.named_data.jndn.encoding.tlv.Tlv.ControlParameters_Uri, endOffset)) {
// Set copy false since we just immediately get the string.
Blob uri = new Blob(decoder.readOptionalBlobTlv(
net.named_data.jndn.encoding.tlv.Tlv.ControlParameters_Uri, endOffset), false);
controlParameters.setUri("" + uri);
}
// decode integers
controlParameters.setLocalControlFeature((int) decoder
.readOptionalNonNegativeIntegerTlv(
net.named_data.jndn.encoding.tlv.Tlv.ControlParameters_LocalControlFeature, endOffset));
controlParameters.setOrigin((int) decoder
.readOptionalNonNegativeIntegerTlv(
net.named_data.jndn.encoding.tlv.Tlv.ControlParameters_Origin, endOffset));
controlParameters.setCost((int) decoder
.readOptionalNonNegativeIntegerTlv(net.named_data.jndn.encoding.tlv.Tlv.ControlParameters_Cost,
endOffset));
// set forwarding flags
if (decoder.peekType(net.named_data.jndn.encoding.tlv.Tlv.ControlParameters_Flags, endOffset)) {
ForwardingFlags flags = new ForwardingFlags();
flags.setNfdForwardingFlags((int) decoder
.readNonNegativeIntegerTlv(net.named_data.jndn.encoding.tlv.Tlv.ControlParameters_Flags));
controlParameters.setForwardingFlags(flags);
}
// decode strategy
if (decoder.peekType(net.named_data.jndn.encoding.tlv.Tlv.ControlParameters_Strategy, endOffset)) {
int strategyEndOffset = decoder
.readNestedTlvsStart(net.named_data.jndn.encoding.tlv.Tlv.ControlParameters_Strategy);
decodeName(controlParameters.getStrategy(), new int[1], new int[1],
decoder, copy);
decoder.finishNestedTlvs(strategyEndOffset);
}
// decode expiration period
controlParameters.setExpirationPeriod(decoder
.readOptionalNonNegativeIntegerTlv(
net.named_data.jndn.encoding.tlv.Tlv.ControlParameters_ExpirationPeriod, endOffset));
decoder.finishNestedTlvs(endOffset);
}
/// <summary>
/// Decode input as an interest in NDN-TLV and set the fields of the interest
/// object.
/// </summary>
///
/// <param name="interest">The Interest object whose fields are updated.</param>
/// <param name="input"></param>
/// <param name="signedPortionBeginOffset">name component and ends just before the final name component (which is assumed to be a signature for a signed interest).</param>
/// <param name="signedPortionEndOffset">name component and ends just before the final name component (which is assumed to be a signature for a signed interest).</param>
/// <param name="copy">unchanged while the Blob values are used.</param>
/// <exception cref="EncodingException">For invalid encoding.</exception>
public override void decodeInterest(Interest interest, ByteBuffer input,
int[] signedPortionBeginOffset, int[] signedPortionEndOffset,
bool copy)
{
TlvDecoder decoder = new TlvDecoder(input);
int endOffset = decoder.readNestedTlvsStart(net.named_data.jndn.encoding.tlv.Tlv.Interest);
decodeName(interest.getName(), signedPortionBeginOffset,
signedPortionEndOffset, decoder, copy);
if (decoder.peekType(net.named_data.jndn.encoding.tlv.Tlv.Selectors, endOffset))
decodeSelectors(interest, decoder, copy);
// Require a Nonce, but don't force it to be 4 bytes.
ByteBuffer nonce = decoder.readBlobTlv(net.named_data.jndn.encoding.tlv.Tlv.Nonce);
interest.setInterestLifetimeMilliseconds(decoder
.readOptionalNonNegativeIntegerTlv(net.named_data.jndn.encoding.tlv.Tlv.InterestLifetime,
endOffset));
if (decoder.peekType(net.named_data.jndn.encoding.tlv.Tlv.Data, endOffset)) {
// Get the bytes of the Link TLV.
int linkBeginOffset = decoder.getOffset();
int linkEndOffset = decoder.readNestedTlvsStart(net.named_data.jndn.encoding.tlv.Tlv.Data);
decoder.seek(linkEndOffset);
interest.setLinkWireEncoding(
new Blob(decoder.getSlice(linkBeginOffset, linkEndOffset),
copy), this);
} else
interest.unsetLink();
interest.setSelectedDelegationIndex((int) decoder
.readOptionalNonNegativeIntegerTlv(net.named_data.jndn.encoding.tlv.Tlv.SelectedDelegation,
endOffset));
if (interest.getSelectedDelegationIndex() >= 0 && !interest.hasLink())
throw new EncodingException(
"Interest has a selected delegation, but no link object");
// Set the nonce last because setting other interest fields clears it.
interest.setNonce(new Blob(nonce, copy));
decoder.finishNestedTlvs(endOffset);
}