/* vim: set expandtab ts=4 sw=4: */ /* * You may redistribute this program and/or modify it under the terms of * the GNU General Public License as published by the Free Software Foundation, * either version 3 of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ #include "interface/Interface.h" #include "interface/addressable/PacketHeaderToUDPAddrInterface.h" #include "memory/Allocator.h" #include "util/platform/Sockaddr.h" #include "util/Assert.h" #include "util/Identity.h" #include "util/Checksum.h" #include "wire/Headers.h" #include "wire/Message.h" #include "wire/Error.h" struct PacketHeaderToUDPAddrInterface_pvt { struct AddrInterface pub; struct Interface* wrapped; Identity }; static uint8_t sendMessage(struct Message* message, struct Interface* iface) { struct PacketHeaderToUDPAddrInterface_pvt* context = Identity_cast((struct PacketHeaderToUDPAddrInterface_pvt*) iface); struct Sockaddr_storage ss; Message_pop(message, &ss, context->pub.addr->addrLen, NULL); struct Sockaddr* addr = &ss.addr; struct Headers_UDPHeader udp; udp.srcPort_be = Endian_hostToBigEndian16(Sockaddr_getPort(context->pub.addr)); udp.destPort_be = Endian_hostToBigEndian16(Sockaddr_getPort(addr)); udp.length_be = Endian_hostToBigEndian16(message->length + Headers_UDPHeader_SIZE); udp.checksum_be = 0; Message_push(message, &udp, sizeof(struct Headers_UDPHeader), NULL); struct Headers_IP6Header ip = { .nextHeader = 17, .hopLimit = 255, }; ip.payloadLength_be = Endian_hostToBigEndian16(message->length); Headers_setIpVersion(&ip); uint8_t* addrPtr = NULL; Assert_true(Sockaddr_getAddress(addr, &addrPtr) == 16); Bits_memcpyConst(ip.destinationAddr, addrPtr, 16); Assert_true(Sockaddr_getAddress(context->pub.addr, &addrPtr) == 16); Bits_memcpyConst(ip.sourceAddr, addrPtr, 16); uint16_t checksum = Checksum_udpIp6(ip.sourceAddr, message->bytes, message->length); ((struct Headers_UDPHeader*)message->bytes)->checksum_be = checksum; Message_push(message, &ip, sizeof(struct Headers_IP6Header), NULL); return Interface_sendMessage(context->wrapped, message); } static uint8_t receiveMessage(struct Message* message, struct Interface* iface) { struct PacketHeaderToUDPAddrInterface_pvt* context = Identity_cast((struct PacketHeaderToUDPAddrInterface_pvt*) iface->receiverContext); if (message->length < Headers_IP6Header_SIZE + Headers_UDPHeader_SIZE) { // runt return Error_NONE; } struct Headers_IP6Header* ip = (struct Headers_IP6Header*) message->bytes; // udp if (ip->nextHeader != 17) { return Error_NONE; } struct Allocator* alloc = Allocator_child(message->alloc); struct Sockaddr* addr = Sockaddr_clone(context->pub.addr, alloc); uint8_t* addrPtr = NULL; Assert_true(Sockaddr_getAddress(addr, &addrPtr) == 16); Bits_memcpyConst(addrPtr, ip->sourceAddr, 16); struct Headers_UDPHeader* udp = (struct Headers_UDPHeader*) (&ip[1]); Sockaddr_setPort(addr, Endian_bigEndianToHost16(udp->srcPort_be)); if (Sockaddr_getPort(context->pub.addr) != Endian_bigEndianToHost16(udp->destPort_be)) { // not the right port return Error_NONE; } Message_shift(message, -(Headers_IP6Header_SIZE + Headers_UDPHeader_SIZE), NULL); Message_push(message, addr, addr->addrLen, NULL); return Interface_receiveMessage(&context->pub.generic, message); } struct AddrInterface* PacketHeaderToUDPAddrInterface_new(struct Interface* toWrap, struct Allocator* alloc, struct Sockaddr* addr) { struct PacketHeaderToUDPAddrInterface_pvt* context = Allocator_malloc(alloc, sizeof(struct PacketHeaderToUDPAddrInterface_pvt)); Bits_memcpyConst(context, (&(struct PacketHeaderToUDPAddrInterface_pvt) { .pub = { .generic = { .sendMessage = sendMessage, .senderContext = context, .allocator = alloc } }, .wrapped = toWrap }), sizeof(struct PacketHeaderToUDPAddrInterface_pvt)); Identity_set(context); context->pub.addr = Sockaddr_clone(addr, alloc); toWrap->receiveMessage = receiveMessage; toWrap->receiverContext = context; return &context->pub; }