error_t mldSendListenerDone(NetInterface *interface, Ipv6Addr *ipAddr)
{
error_t error;
size_t offset;
MldMessage *message;
ChunkedBuffer *buffer;
Ipv6PseudoHeader pseudoHeader;
//Make sure the specified address is a valid multicast address
if(!ipv6IsMulticastAddr(ipAddr))
return ERROR_INVALID_ADDRESS;
//The link-scope all-nodes address (FF02::1) is handled as a special
//case. The host never sends a report for that address
if(ipv6CompAddr(ipAddr, &IPV6_LINK_LOCAL_ALL_NODES_ADDR))
return ERROR_INVALID_ADDRESS;
//Allocate a memory buffer to hold a MLD message
buffer = ipAllocBuffer(sizeof(MldMessage), &offset);
//Failed to allocate memory?
if(!buffer) return ERROR_OUT_OF_MEMORY;
//Point to the beginning of the MLD message
message = chunkedBufferAt(buffer, offset);
//Format the Multicast Listener Done message
message->type = ICMPV6_TYPE_MULTICAST_LISTENER_DONE_V1;
message->code = 0;
message->checksum = 0;
message->maxRespDelay = 0;
message->reserved = 0;
message->multicastAddr = *ipAddr;
//Format IPv6 pseudo header
pseudoHeader.srcAddr = interface->ipv6Config.linkLocalAddr;
pseudoHeader.destAddr = IPV6_LINK_LOCAL_ALL_ROUTERS_ADDR;
pseudoHeader.length = HTONS(sizeof(MldMessage));
pseudoHeader.reserved = 0;
pseudoHeader.nextHeader = IPV6_ICMPV6_HEADER;
//Message checksum calculation
message->checksum = ipCalcUpperLayerChecksumEx(&pseudoHeader,
sizeof(Ipv6PseudoHeader), buffer, offset, sizeof(MldMessage));
//Debug message
TRACE_INFO("Sending MLD message (%" PRIuSIZE " bytes)...\r\n", sizeof(MldMessage));
//Dump message contents for debugging purpose
mldDumpMessage(message);
//The Multicast Listener Done message is sent to the all-routers multicast address
error = ipv6SendDatagram(interface, &pseudoHeader, buffer, offset, MLD_HOP_LIMIT);
//Free previously allocated memory
chunkedBufferFree(buffer);
//Return status code
return error;
}
error_t ndpSendNeighborAdv(NetInterface *interface,
const Ipv6Addr *targetIpAddr, const Ipv6Addr *destIpAddr)
{
error_t error;
size_t offset;
size_t length;
ChunkedBuffer *buffer;
NdpNeighborAdvMessage *message;
Ipv6PseudoHeader pseudoHeader;
//Allocate a memory buffer to hold the Neighbor Advertisement
//message and the Target Link-Layer Address option
buffer = ipAllocBuffer(sizeof(NdpNeighborAdvMessage) +
sizeof(NdpLinkLayerAddrOption), &offset);
//Failed to allocate memory?
if(!buffer) return ERROR_OUT_OF_MEMORY;
//Point to the beginning of the message
message = chunkedBufferAt(buffer, offset);
//Format Neighbor Advertisement message
message->type = ICMPV6_TYPE_NEIGHBOR_ADV;
message->code = 0;
message->checksum = 0;
message->reserved1 = 0;
message->o = TRUE;
message->s = FALSE;
message->r = FALSE;
message->reserved2 = 0;
message->targetAddr = *targetIpAddr;
//Length of the message, excluding any option
length = sizeof(NdpNeighborAdvMessage);
//Add Target Link-Layer Address option
ndpAddOption(message, &length, NDP_OPT_TARGET_LINK_LAYER_ADDR,
&interface->macAddr, sizeof(MacAddr));
//Adjust the length of the multi-part buffer
chunkedBufferSetLength(buffer, offset + length);
//Format IPv6 pseudo header
pseudoHeader.srcAddr = *targetIpAddr;
pseudoHeader.destAddr = *destIpAddr;
pseudoHeader.length = htonl(length);
pseudoHeader.reserved = 0;
pseudoHeader.nextHeader = IPV6_ICMPV6_HEADER;
//Destination IP address is the unspecified address?
if(ipv6CompAddr(destIpAddr, &IPV6_UNSPECIFIED_ADDR))
{
//If the destination is the unspecified address, the node
//must set the Solicited flag to zero and multicast the
//advertisement to the all-nodes address
pseudoHeader.destAddr = IPV6_LINK_LOCAL_ALL_NODES_ADDR;
}
else
{
//Otherwise, the node must set the Solicited flag to one and
//unicast the advertisement to the destination IP address
message->s = TRUE;
}
//Calculate ICMPv6 header checksum
message->checksum = ipCalcUpperLayerChecksumEx(&pseudoHeader,
sizeof(Ipv6PseudoHeader), buffer, offset, length);
//Debug message
TRACE_INFO("Sending Neighbor Advertisement message (%" PRIuSIZE " bytes)...\r\n", length);
//Dump message contents for debugging purpose
ndpDumpNeighborAdvMessage(message);
//Send Neighbor Advertisement message
error = ipv6SendDatagram(interface, &pseudoHeader, buffer, offset, NDP_HOP_LIMIT);
//Free previously allocated memory
chunkedBufferFree(buffer);
//Return status code
return error;
}
error_t ndpSendNeighborSol(NetInterface *interface, const Ipv6Addr *targetIpAddr)
{
error_t error;
size_t offset;
size_t length;
ChunkedBuffer *buffer;
NdpNeighborSolMessage *message;
Ipv6PseudoHeader pseudoHeader;
//Allocate a memory buffer to hold the Neighbor Solicitation
//message and the Source Link-Layer Address option
buffer = ipAllocBuffer(sizeof(NdpNeighborSolMessage) +
sizeof(NdpLinkLayerAddrOption), &offset);
//Failed to allocate memory?
if(!buffer) return ERROR_OUT_OF_MEMORY;
//Point to the beginning of the message
message = chunkedBufferAt(buffer, offset);
//Format Neighbor Solicitation message
message->type = ICMPV6_TYPE_NEIGHBOR_SOL;
message->code = 0;
message->checksum = 0;
message->reserved = 0;
message->targetAddr = *targetIpAddr;
//Length of the message, excluding any option
length = sizeof(NdpNeighborSolMessage);
//Check whether the target address is a tentative address
if(ipv6IsTentativeAddr(interface, targetIpAddr))
{
//The IPv6 source is set to the unspecified address
pseudoHeader.srcAddr = IPV6_UNSPECIFIED_ADDR;
}
else
{
//The Source Link-Layer Address option must not be included
//when the host IPv6 address is unspecified
if(!ipv6CompAddr(&interface->ipv6Config.linkLocalAddr, &IPV6_UNSPECIFIED_ADDR))
{
//Add Source Link-Layer Address option
ndpAddOption(message, &length, NDP_OPT_SOURCE_LINK_LAYER_ADDR,
&interface->macAddr, sizeof(MacAddr));
}
//Set the IPv6 source address
pseudoHeader.srcAddr = interface->ipv6Config.linkLocalAddr;
}
//Adjust the length of the multi-part buffer
chunkedBufferSetLength(buffer, offset + length);
//Compute the solicited-node multicast address that
//corresponds to the target IPv6 address
ipv6ComputeSolicitedNodeAddr(targetIpAddr, &pseudoHeader.destAddr);
//Format IPv6 pseudo header
pseudoHeader.length = htonl(length);
pseudoHeader.reserved = 0;
pseudoHeader.nextHeader = IPV6_ICMPV6_HEADER;
//Calculate ICMPv6 header checksum
message->checksum = ipCalcUpperLayerChecksumEx(&pseudoHeader,
sizeof(Ipv6PseudoHeader), buffer, offset, length);
//Debug message
TRACE_INFO("Sending Neighbor Solicitation message (%" PRIuSIZE " bytes)...\r\n", length);
//Dump message contents for debugging purpose
ndpDumpNeighborSolMessage(message);
//Send Neighbor Solicitation message
error = ipv6SendDatagram(interface, &pseudoHeader, buffer, offset, NDP_HOP_LIMIT);
//Free previously allocated memory
chunkedBufferFree(buffer);
//Return status code
return error;
}
error_t icmpv6SendErrorMessage(NetInterface *interface, uint8_t type,
uint8_t code, uint32_t parameter, const ChunkedBuffer *ipPacket)
{
error_t error;
size_t offset;
size_t length;
Ipv6Header *ipHeader;
ChunkedBuffer *icmpMessage;
Icmpv6ErrorMessage *icmpHeader;
Ipv6PseudoHeader pseudoHeader;
//Retrieve the length of the invoking IPv6 packet
length = chunkedBufferGetLength(ipPacket);
//Check the length of the IPv6 packet
if(length < sizeof(Ipv6Header))
return ERROR_INVALID_LENGTH;
//Point to the header of the invoking packet
ipHeader = chunkedBufferAt(ipPacket, 0);
//Sanity check
if(!ipHeader) return ERROR_FAILURE;
//Never respond to a packet destined to an IPv6 multicast address
if(ipv6IsMulticastAddr(&ipHeader->destAddr))
return ERROR_INVALID_ADDRESS;
//Return as much of invoking IPv6 packet as possible without
//the ICMPv6 packet exceeding the minimum IPv6 MTU
length = MIN(length, IPV6_DEFAULT_MTU -
sizeof(Ipv6Header) - sizeof(Icmpv6ErrorMessage));
//Allocate a memory buffer to hold the ICMPv6 message
icmpMessage = ipAllocBuffer(sizeof(Icmpv6ErrorMessage), &offset);
//Failed to allocate memory?
if(!icmpMessage) return ERROR_OUT_OF_MEMORY;
//Point to the ICMPv6 header
icmpHeader = chunkedBufferAt(icmpMessage, offset);
//Format ICMPv6 Error message
icmpHeader->type = type;
icmpHeader->code = code;
icmpHeader->checksum = 0;
icmpHeader->parameter = htonl(parameter);
//Copy incoming IPv6 packet contents
error = chunkedBufferConcat(icmpMessage, ipPacket, 0, length);
//Any error to report?
if(error)
{
//Clean up side effects
chunkedBufferFree(icmpMessage);
//Exit immediately
return error;
}
//Get the length of the resulting message
length = chunkedBufferGetLength(icmpMessage) - offset;
//Format IPv6 pseudo header
pseudoHeader.srcAddr = ipHeader->destAddr;
pseudoHeader.destAddr = ipHeader->srcAddr;
pseudoHeader.length = htonl(length);
pseudoHeader.reserved = 0;
pseudoHeader.nextHeader = IPV6_ICMPV6_HEADER;
//Message checksum calculation
icmpHeader->checksum = ipCalcUpperLayerChecksumEx(&pseudoHeader,
sizeof(Ipv6PseudoHeader), icmpMessage, offset, length);
//Debug message
TRACE_INFO("Sending ICMPv6 Error message (%" PRIuSIZE " bytes)...\r\n", length);
//Dump message contents for debugging purpose
icmpv6DumpErrorMessage(icmpHeader);
//Send ICMPv6 Error message
error = ipv6SendDatagram(interface, &pseudoHeader,
icmpMessage, offset, IPV6_DEFAULT_HOP_LIMIT);
//Free previously allocated memory
chunkedBufferFree(icmpMessage);
//Return status code
return error;
}
void icmpv6ProcessEchoRequest(NetInterface *interface, Ipv6PseudoHeader *requestPseudoHeader,
const ChunkedBuffer *request, size_t requestOffset)
{
error_t error;
size_t requestLength;
size_t replyOffset;
size_t replyLength;
ChunkedBuffer *reply;
Icmpv6EchoMessage *requestHeader;
Icmpv6EchoMessage *replyHeader;
Ipv6PseudoHeader replyPseudoHeader;
//Retrieve the length of the Echo Request message
requestLength = chunkedBufferGetLength(request) - requestOffset;
//Ensure the packet length is correct
if(requestLength < sizeof(Icmpv6EchoMessage))
return;
//Point to the Echo Request header
requestHeader = chunkedBufferAt(request, requestOffset);
//Sanity check
if(!requestHeader) return;
//Debug message
TRACE_INFO("ICMPv6 Echo Request message received (%" PRIuSIZE " bytes)...\r\n", requestLength);
//Dump message contents for debugging purpose
icmpv6DumpEchoMessage(requestHeader);
//Allocate memory to hold the Echo Reply message
reply = ipAllocBuffer(sizeof(Icmpv6EchoMessage), &replyOffset);
//Failed to allocate memory?
if(!reply) return;
//Point to the Echo Reply header
replyHeader = chunkedBufferAt(reply, replyOffset);
//Format Echo Reply header
replyHeader->type = ICMPV6_TYPE_ECHO_REPLY;
replyHeader->code = 0;
replyHeader->checksum = 0;
replyHeader->identifier = requestHeader->identifier;
replyHeader->sequenceNumber = requestHeader->sequenceNumber;
//Point to the first data byte
requestOffset += sizeof(Icmpv6EchoMessage);
requestLength -= sizeof(Icmpv6EchoMessage);
//Copy data
error = chunkedBufferConcat(reply, request, requestOffset, requestLength);
//Any error to report?
if(error)
{
//Clean up side effects
chunkedBufferFree(reply);
//Exit immediately
return;
}
//Get the length of the resulting message
replyLength = chunkedBufferGetLength(reply) - replyOffset;
//Format IPv6 pseudo header
replyPseudoHeader.srcAddr = requestPseudoHeader->destAddr;
replyPseudoHeader.destAddr = requestPseudoHeader->srcAddr;
replyPseudoHeader.length = htonl(replyLength);
replyPseudoHeader.reserved = 0;
replyPseudoHeader.nextHeader = IPV6_ICMPV6_HEADER;
//Message checksum calculation
replyHeader->checksum = ipCalcUpperLayerChecksumEx(&replyPseudoHeader,
sizeof(Ipv6PseudoHeader), reply, replyOffset, replyLength);
//Debug message
TRACE_INFO("Sending ICMPv6 Echo Reply message (%" PRIuSIZE " bytes)...\r\n", replyLength);
//Dump message contents for debugging purpose
icmpv6DumpEchoMessage(replyHeader);
//Send Echo Reply message
ipv6SendDatagram(interface, &replyPseudoHeader, reply, replyOffset, IPV6_DEFAULT_HOP_LIMIT);
//Free previously allocated memory block
chunkedBufferFree(reply);
}