static ndn_Error
decodeSelectors(struct ndn_Interest *interest, struct ndn_TlvDecoder *decoder)
{
ndn_Error error;
size_t endOffset;
int gotExpectedType;
if ((error = ndn_TlvDecoder_readNestedTlvsStart(decoder, ndn_Tlv_Selectors, &endOffset)))
return error;
if ((error = ndn_TlvDecoder_readOptionalNonNegativeIntegerTlv
(decoder, ndn_Tlv_MinSuffixComponents, endOffset, &interest->minSuffixComponents)))
return error;
if ((error = ndn_TlvDecoder_readOptionalNonNegativeIntegerTlv
(decoder, ndn_Tlv_MaxSuffixComponents, endOffset, &interest->maxSuffixComponents)))
return error;
if ((error = ndn_TlvDecoder_peekType
(decoder, ndn_Tlv_PublisherPublicKeyLocator, endOffset, &gotExpectedType)))
return error;
if (gotExpectedType) {
if ((error = ndn_decodeTlvKeyLocator
(ndn_Tlv_PublisherPublicKeyLocator, &interest->keyLocator, decoder)))
return error;
}
else
// Clear the key locator.
ndn_KeyLocator_initialize(&interest->keyLocator, interest->keyLocator.keyName.components, interest->keyLocator.keyName.maxComponents);
if ((error = ndn_TlvDecoder_peekType(decoder, ndn_Tlv_Exclude, endOffset, &gotExpectedType)))
return error;
if (gotExpectedType) {
if ((error = decodeExclude(&interest->exclude, decoder)))
return error;
}
else
interest->exclude.nEntries = 0;
if ((error = ndn_TlvDecoder_readOptionalNonNegativeIntegerTlv
(decoder, ndn_Tlv_ChildSelector, endOffset, &interest->childSelector)))
return error;
if ((error = ndn_TlvDecoder_readBooleanTlv
(decoder, ndn_Tlv_MustBeFresh, endOffset, &interest->mustBeFresh)))
return error;
if ((error = ndn_TlvDecoder_finishNestedTlvs(decoder, endOffset)))
return error;
return NDN_ERROR_success;
}
static ndn_Error
decodeMetaInfo(struct ndn_MetaInfo *metaInfo, struct ndn_TlvDecoder *decoder)
{
ndn_Error error;
size_t endOffset;
int gotExpectedType;
if ((error = ndn_TlvDecoder_readNestedTlvsStart(decoder, ndn_Tlv_MetaInfo, &endOffset)))
return error;
int type;
if ((error = ndn_TlvDecoder_readOptionalNonNegativeIntegerTlv
(decoder, ndn_Tlv_ContentType, endOffset, &type)))
return error;
if (type < 0 || type == ndn_ContentType_BLOB)
// Default to BLOB if the value is omitted.
metaInfo->type = ndn_ContentType_BLOB;
else if (type == ndn_ContentType_LINK ||
type == ndn_ContentType_KEY ||
type == ndn_ContentType_NACK)
// The ContentType enum is set up with the correct integer for each NDN-TLV ContentType.
metaInfo->type = type;
else {
// Unrecognized content type.
metaInfo->type = ndn_ContentType_OTHER_CODE;
metaInfo->otherTypeCode = type;
}
if ((error = ndn_TlvDecoder_readOptionalNonNegativeIntegerTlvAsDouble
(decoder, ndn_Tlv_FreshnessPeriod, endOffset, &metaInfo->freshnessPeriod)))
return error;
if ((error = ndn_TlvDecoder_peekType
(decoder, ndn_Tlv_FinalBlockId, endOffset, &gotExpectedType)))
return error;
if (gotExpectedType) {
size_t finalBlockIdEndOffset;
if ((error = ndn_TlvDecoder_readNestedTlvsStart
(decoder, ndn_Tlv_FinalBlockId, &finalBlockIdEndOffset)))
return error;
if ((error = ndn_decodeTlvNameComponent(&metaInfo->finalBlockId, decoder)))
return error;
if ((error = ndn_TlvDecoder_finishNestedTlvs(decoder, finalBlockIdEndOffset)))
return error;
}
else
ndn_NameComponent_initialize(&metaInfo->finalBlockId, 0, 0);
// Set fields not used by NDN-TLV to none.
metaInfo->timestampMilliseconds = -1;
if ((error = ndn_TlvDecoder_finishNestedTlvs(decoder, endOffset)))
return error;
return NDN_ERROR_success;
}
static ndn_Error
decodeMetaInfo(struct ndn_MetaInfo *metaInfo, struct ndn_TlvDecoder *decoder)
{
ndn_Error error;
size_t endOffset;
int gotExpectedType;
if ((error = ndn_TlvDecoder_readNestedTlvsStart(decoder, ndn_Tlv_MetaInfo, &endOffset)))
return error;
// The ContentType enum is set up with the correct integer for each NDN-TLV ContentType.
if ((error = ndn_TlvDecoder_readOptionalNonNegativeIntegerTlv
(decoder, ndn_Tlv_ContentType, endOffset, (int *)&metaInfo->type)))
return error;
if ((int)metaInfo->type < 0)
// Set to the actual value for the default.
metaInfo->type = ndn_ContentType_BLOB;
if ((error = ndn_TlvDecoder_readOptionalNonNegativeIntegerTlvAsDouble
(decoder, ndn_Tlv_FreshnessPeriod, endOffset, &metaInfo->freshnessPeriod)))
return error;
if ((error = ndn_TlvDecoder_peekType
(decoder, ndn_Tlv_FinalBlockId, endOffset, &gotExpectedType)))
return error;
if (gotExpectedType) {
size_t finalBlockIdEndOffset;
if ((error = ndn_TlvDecoder_readNestedTlvsStart
(decoder, ndn_Tlv_FinalBlockId, &finalBlockIdEndOffset)))
return error;
if ((error = ndn_TlvDecoder_readBlobTlv
(decoder, ndn_Tlv_NameComponent, &metaInfo->finalBlockId.value)))
return error;
if ((error = ndn_TlvDecoder_finishNestedTlvs(decoder, finalBlockIdEndOffset)))
return error;
}
else
ndn_NameComponent_initialize(&metaInfo->finalBlockId, 0, 0);
// Set fields not used by NDN-TLV to none.
metaInfo->timestampMilliseconds = -1;
if ((error = ndn_TlvDecoder_finishNestedTlvs(decoder, endOffset)))
return error;
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;
}
static ndn_Error
ndn_decodeTlvInterestV02
(struct ndn_Interest *interest, size_t *signedPortionBeginOffset,
size_t *signedPortionEndOffset, struct ndn_TlvDecoder *decoder)
{
ndn_Error error;
size_t endOffset;
int gotExpectedType;
if ((error = ndn_TlvDecoder_readNestedTlvsStart(decoder, ndn_Tlv_Interest, &endOffset)))
return error;
if ((error = ndn_decodeTlvName
(&interest->name, signedPortionBeginOffset, signedPortionEndOffset,
decoder)))
return error;
if ((error = ndn_TlvDecoder_peekType(decoder, ndn_Tlv_Selectors, endOffset, &gotExpectedType)))
return error;
if (gotExpectedType) {
if ((error = decodeSelectors(interest, decoder)))
return error;
}
else {
// Set selectors to none.
interest->minSuffixComponents = -1;
interest->maxSuffixComponents = -1;
ndn_KeyLocator_initialize
(&interest->keyLocator, interest->keyLocator.keyName.components,
interest->keyLocator.keyName.maxComponents);
interest->exclude.nEntries = 0;
interest->childSelector = -1;
interest->mustBeFresh = 0;
}
// Require a Nonce, but don't force it to be 4 bytes.
if ((error = ndn_TlvDecoder_readBlobTlv(decoder, ndn_Tlv_Nonce, &interest->nonce)))
return error;
if ((error = ndn_TlvDecoder_readOptionalNonNegativeIntegerTlvAsDouble
(decoder, ndn_Tlv_InterestLifetime, endOffset, &interest->interestLifetimeMilliseconds)))
return error;
// Get the encoded sequence of delegations as is.
if ((error = ndn_TlvDecoder_readOptionalBlobTlv
(decoder, ndn_Tlv_ForwardingHint, endOffset,
&interest->forwardingHintWireEncoding)))
return error;
if ((error = ndn_TlvDecoder_peekType(decoder, ndn_Tlv_Data, endOffset, &gotExpectedType)))
return error;
if (gotExpectedType) {
// Get the bytes of the Link TLV.
size_t linkBeginOffset = decoder->offset;
size_t linkEndOffset;
if ((error = ndn_TlvDecoder_readNestedTlvsStart
(decoder, ndn_Tlv_Data, &linkEndOffset)))
return error;
ndn_TlvDecoder_seek(decoder, linkEndOffset);
if ((error = ndn_TlvDecoder_getSlice
(decoder, linkBeginOffset, linkEndOffset, &interest->linkWireEncoding)))
return error;
}
else
ndn_Blob_initialize(&interest->linkWireEncoding, 0, 0);
if ((error = ndn_TlvDecoder_readOptionalNonNegativeIntegerTlv
(decoder, ndn_Tlv_SelectedDelegation, endOffset,
&interest->selectedDelegationIndex)))
return error;
if (interest->selectedDelegationIndex >= 0 && !interest->linkWireEncoding.value)
return NDN_ERROR_Interest_has_a_selected_delegation_but_no_link_object;
if ((error = ndn_TlvDecoder_finishNestedTlvs(decoder, endOffset)))
return error;
return NDN_ERROR_success;
}
