ndn_Error
ndn_encodeTlvSignatureInfo
(const struct ndn_Signature *signatureInfo, struct ndn_TlvEncoder *encoder)
{
if (signatureInfo->type == ndn_SignatureType_Generic) {
// Handle a Generic signature separately since it has the entire encoding.
const struct ndn_Blob *encoding = &signatureInfo->signatureInfoEncoding;
ndn_Error error;
size_t endOffset;
uint64_t signatureType;
// Do a test decoding to sanity check that it is valid TLV.
struct ndn_TlvDecoder decoder;
ndn_TlvDecoder_initialize(&decoder, encoding->value, encoding->length);
error = ndn_TlvDecoder_readNestedTlvsStart
(&decoder, ndn_Tlv_SignatureInfo, &endOffset);
if (!error)
error = ndn_TlvDecoder_readNonNegativeIntegerTlv
(&decoder, ndn_Tlv_SignatureType, &signatureType);
if (!error)
error = ndn_TlvDecoder_finishNestedTlvs(&decoder, endOffset);
if (error)
return NDN_ERROR_The_Generic_signature_encoding_is_not_a_valid_NDN_TLV_SignatureInfo;
return ndn_TlvEncoder_writeArray(encoder, encoding->value, encoding->length);
}
if (signatureInfo->type == ndn_SignatureType_Sha256WithRsaSignature ||
signatureInfo->type == ndn_SignatureType_Sha256WithEcdsaSignature ||
signatureInfo->type == ndn_SignatureType_HmacWithSha256Signature)
return ndn_TlvEncoder_writeNestedTlv
(encoder, ndn_Tlv_SignatureInfo,
encodeSignatureWithKeyLocatorAndValidityPeriodValue, signatureInfo, 0);
else if (signatureInfo->type == ndn_SignatureType_DigestSha256Signature)
return ndn_TlvEncoder_writeNestedTlv
(encoder, ndn_Tlv_SignatureInfo, encodeDigestSha256Value,
signatureInfo, 0);
else
return NDN_ERROR_encodeSignatureInfo_unrecognized_SignatureType;
}
/**
* This private function is called by ndn_TlvEncoder_writeNestedTlv to write the TLVs in the body of the Interest value.
* @param context This is the InterestValueContext struct pointer which was passed to writeTlv.
* @param encoder the ndn_TlvEncoder which is calling this.
* @return 0 for success, else an error code.
*/
static ndn_Error
encodeInterestValue(const void *context, struct ndn_TlvEncoder *encoder)
{
const struct InterestValueContext *interestValueContext =
(const struct InterestValueContext *)context;
const struct ndn_Interest *interest = interestValueContext->interest;
ndn_Error error;
uint8_t nonceBuffer[4];
struct ndn_Blob nonceBlob;
if ((error = ndn_encodeTlvName
(&interest->name, interestValueContext->signedPortionBeginOffset,
interestValueContext->signedPortionEndOffset, encoder)))
return error;
// For Selectors, set omitZeroLength true.
if ((error = ndn_TlvEncoder_writeNestedTlv(encoder, ndn_Tlv_Selectors, encodeSelectorsValue, interest, 1)))
return error;
// Encode the Nonce as 4 bytes.
nonceBlob.length = sizeof(nonceBuffer);
if (interest->nonce.length == 0) {
// Generate a random nonce.
if ((error = ndn_generateRandomBytes(nonceBuffer, sizeof(nonceBuffer))))
return error;
nonceBlob.value = nonceBuffer;
}
else if (interest->nonce.length < 4) {
// TLV encoding requires 4 bytes, so pad out to 4 using random bytes.
ndn_memcpy(nonceBuffer, interest->nonce.value, interest->nonce.length);
if ((error = ndn_generateRandomBytes
(nonceBuffer + interest->nonce.length,
sizeof(nonceBuffer) - interest->nonce.length)))
return error;
nonceBlob.value = nonceBuffer;
}
else
// TLV encoding requires 4 bytes, so truncate to 4.
nonceBlob.value = interest->nonce.value;
if ((error = ndn_TlvEncoder_writeBlobTlv(encoder, ndn_Tlv_Nonce, &nonceBlob)))
return error;
if ((error = ndn_TlvEncoder_writeOptionalNonNegativeIntegerTlvFromDouble
(encoder, ndn_Tlv_InterestLifetime, interest->interestLifetimeMilliseconds)))
return error;
if (interest->forwardingHintWireEncoding.value &&
interest->forwardingHintWireEncoding.length > 0) {
if (interest->selectedDelegationIndex >= 0)
return NDN_ERROR_An_Interest_may_not_have_a_selected_delegation_when_encoding_a_forwarding_hint;
if (interest->linkWireEncoding.value)
return NDN_ERROR_An_Interest_may_not_have_a_link_object_when_encoding_a_forwarding_hint;
// Add the encoded sequence of delegations as is.
if ((error = ndn_TlvEncoder_writeBlobTlv
(encoder, ndn_Tlv_ForwardingHint, &interest->forwardingHintWireEncoding)))
return error;
}
if (interest->linkWireEncoding.value) {
// Encode the entire link as is.
if ((error = ndn_TlvEncoder_writeArray
(encoder, interest->linkWireEncoding.value, interest->linkWireEncoding.length)))
return error;
}
if ((error = ndn_TlvEncoder_writeOptionalNonNegativeIntegerTlv
(encoder, ndn_Tlv_SelectedDelegation, interest->selectedDelegationIndex)))
return error;
return NDN_ERROR_success;
}