ndn_Error
ndn_TlvDecoder_skipRemainingNestedTlvs
(struct ndn_TlvDecoder *self, size_t endOffset, int skipCritical)
{
while(self->offset < endOffset) {
ndn_Error error;
uint64_t type;
int critical;
uint64_t lengthVarNumber;
if ((error = ndn_TlvDecoder_readVarNumber(self, &type)))
return error;
if ((error = ndn_TlvDecoder_readVarNumber(self, &lengthVarNumber)))
return error;
critical = (type <= 31 || (type & 1) == 1);
if (critical && !skipCritical)
return NDN_ERROR_Unrecognized_critical_TLV_type_code;
// Silently ignore if the length is larger than size_t.
self->offset += (size_t)lengthVarNumber;
if (self->offset > self->inputLength)
return NDN_ERROR_TLV_length_exceeds_buffer_length;
}
if (self->offset != endOffset)
return NDN_ERROR_TLV_length_does_not_equal_total_length_of_nested_TLVs;
return NDN_ERROR_success;
}
ndn_Error
ndn_decodeTlvNameComponent
(struct ndn_NameComponent *component, struct ndn_TlvDecoder *decoder)
{
ndn_Error error;
uint64_t type;
size_t saveOffset;
saveOffset = decoder->offset;
if ((error = ndn_TlvDecoder_readVarNumber(decoder, &type)))
return error;
// Restore the position.
ndn_TlvDecoder_seek(decoder, saveOffset);
if ((error = ndn_TlvDecoder_readBlobTlv(decoder, type, &component->value)))
return error;
if (type == ndn_Tlv_ImplicitSha256DigestComponent)
component->type = ndn_NameComponentType_IMPLICIT_SHA256_DIGEST;
else if (type == ndn_Tlv_ParametersSha256DigestComponent)
component->type = ndn_NameComponentType_PARAMETERS_SHA256_DIGEST;
else if (type == ndn_Tlv_NameComponent)
component->type = ndn_NameComponentType_GENERIC;
else {
// Unrecognized type code.
component->type = ndn_NameComponentType_OTHER_CODE;
component->otherTypeCode = (int)type;
}
return NDN_ERROR_success;
}
ndn_Error
ndn_decodeTlvNameComponent
(struct ndn_NameComponent *component, struct ndn_TlvDecoder *decoder)
{
ndn_Error error;
uint64_t type;
size_t saveOffset;
saveOffset = decoder->offset;
if ((error = ndn_TlvDecoder_readVarNumber(decoder, &type)))
return error;
// Restore the position.
ndn_TlvDecoder_seek(decoder, saveOffset);
if ((error = ndn_TlvDecoder_readBlobTlv(decoder, type, &component->value)))
return error;
if (type == ndn_Tlv_ImplicitSha256DigestComponent)
component->type = ndn_NameComponentType_IMPLICIT_SHA256_DIGEST;
else
component->type = ndn_NameComponentType_GENERIC;
return NDN_ERROR_success;
}
ndn_Error
ndn_decodeTlvLpPacket
(struct ndn_LpPacket *lpPacket, struct ndn_TlvDecoder *decoder)
{
ndn_Error error;
size_t endOffset;
ndn_LpPacket_clear(lpPacket);
if ((error = ndn_TlvDecoder_readNestedTlvsStart
(decoder, ndn_Tlv_LpPacket_LpPacket, &endOffset)))
return error;
while (decoder->offset < endOffset) {
// Imitate ndn_TlvDecoder_readTypeAndLength.
uint64_t fieldTypeVarNumber;
int fieldType;
uint64_t fieldLength;
size_t fieldEndOffset;
if ((error = ndn_TlvDecoder_readVarNumber(decoder, &fieldTypeVarNumber)))
return error;
fieldType = (int)fieldTypeVarNumber;
if ((error = ndn_TlvDecoder_readVarNumber(decoder, &fieldLength)))
return error;
fieldEndOffset = decoder->offset + (size_t)fieldLength;
if (fieldEndOffset > decoder->inputLength)
return NDN_ERROR_TLV_length_exceeds_buffer_length;
if (fieldType == ndn_Tlv_LpPacket_Fragment) {
// Set the fragment to the bytes of the TLV value.
if ((error = ndn_TlvDecoder_getSlice
(decoder, decoder->offset, fieldEndOffset,
&lpPacket->fragmentWireEncoding)))
return error;
ndn_TlvDecoder_seek(decoder, fieldEndOffset);
// The fragment is supposed to be the last field.
break;
}
else if (fieldType == ndn_Tlv_LpPacket_Nack) {
struct ndn_NetworkNack *networkNack;
int code;
if ((error = ndn_NetworkNack_add(lpPacket, &networkNack)))
return error;
if ((error = ndn_TlvDecoder_readOptionalNonNegativeIntegerTlv
(decoder, ndn_Tlv_LpPacket_NackReason, fieldEndOffset, &code)))
return error;
// The enum numeric values are the same as this wire format, so use as is.
if (code < 0 || code == ndn_NetworkNackReason_NONE)
// This includes an omitted NackReason.
networkNack->reason = ndn_NetworkNackReason_NONE;
else if (code == ndn_NetworkNackReason_CONGESTION ||
code == ndn_NetworkNackReason_DUPLICATE ||
code == ndn_NetworkNackReason_NO_ROUTE)
networkNack->reason = code;
else {
// Unrecognized reason.
networkNack->reason = ndn_NetworkNackReason_OTHER_CODE;
networkNack->otherReasonCode = code;
}
}
else if (fieldType == ndn_Tlv_LpPacket_IncomingFaceId) {
struct ndn_IncomingFaceId *incomingFaceId;
if ((error = ndn_IncomingFaceId_add(lpPacket, &incomingFaceId)))
return error;
if ((error = ndn_TlvDecoder_readNonNegativeInteger
(decoder, fieldLength, &incomingFaceId->faceId)))
return error;
}
else {
// Unrecognized field type. The conditions for ignoring are here:
// http://redmine.named-data.net/projects/nfd/wiki/NDNLPv2
int canIgnore =
(fieldType >= ndn_Tlv_LpPacket_IGNORE_MIN &&
fieldType <= ndn_Tlv_LpPacket_IGNORE_MAX &&
(fieldType & 0x01) == 1);
if (!canIgnore)
return NDN_ERROR_did_not_get_the_expected_TLV_type;
// Ignore.
ndn_TlvDecoder_seek(decoder, fieldEndOffset);
}
if ((error = ndn_TlvDecoder_finishNestedTlvs(decoder, fieldEndOffset)))
return error;
}
if ((error = ndn_TlvDecoder_finishNestedTlvs(decoder, endOffset)))
return error;
return NDN_ERROR_success;
}
