diff options
Diffstat (limited to 'src/uqm/supermelee/netplay/packethandlers.c')
| -rw-r--r-- | src/uqm/supermelee/netplay/packethandlers.c | 649 |
1 files changed, 649 insertions, 0 deletions
diff --git a/src/uqm/supermelee/netplay/packethandlers.c b/src/uqm/supermelee/netplay/packethandlers.c new file mode 100644 index 0000000..5d2d8f4 --- /dev/null +++ b/src/uqm/supermelee/netplay/packethandlers.c @@ -0,0 +1,649 @@ +/* + * Copyright 2006 Serge van den Boom <svdb@stack.nl> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 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, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#define PORT_WANT_ERRNO +#include "port.h" + +#define NETCONNECTION_INTERNAL +#include "netplay.h" +#include "packethandlers.h" + +#include "netinput.h" +#include "netmisc.h" +#include "packetsenders.h" +#include "proto/npconfirm.h" +#include "proto/ready.h" +#include "proto/reset.h" +#include "libs/log.h" + +#include "../../controls.h" + // for BATTLE_INPUT_STATE +#include "../../init.h" + // for NUM_PLAYERS +#include "../../globdata.h" + // for GLOBAL +#include "../melee.h" + // for various update functions. +#include "../meleeship.h" + // for MeleeShip +#include "../pickmele.h" + // for various update functions. +#include "libs/mathlib.h" + // for TFB_SeedRandom + +#include <errno.h> + + +static bool +testNetState(bool condition, PacketType type) { + if (!condition) { + log_add(log_Error, "Packet of type '%s' received from wrong " + "state.", packetTypeData[type].name); + errno = EBADMSG; + } + return condition; +} + +static int +versionCompare(int major1, int minor1, int patch1, + int major2, int minor2, int patch2) { + if (major1 < major2) + return -1; + if (major1 > major2) + return 1; + + if (minor1 < minor2) + return -1; + if (minor1 > minor2) + return 1; + + if (patch1 < patch2) + return -1; + if (patch1 > patch2) + return 1; + + return 0; +} + +int +PacketHandler_Init(NetConnection *conn, const Packet_Init *packet) { + if (conn->stateFlags.reset.localReset) + return 0; + if (conn->stateFlags.reset.remoteReset) { + errno = EBADMSG; + return -1; + } + + if (!testNetState(conn->state == NetState_init && + !conn->stateFlags.ready.remoteReady, PACKET_INIT)) + return -1; // errno is set + + if (packet->protoVersion.major != NETPLAY_PROTOCOL_VERSION_MAJOR || + packet->protoVersion.minor != NETPLAY_PROTOCOL_VERSION_MINOR) { + sendAbort (conn, AbortReason_versionMismatch); + abortFeedback(conn, AbortReason_versionMismatch); + log_add(log_Error, "Protocol version %d.%d not supported.", + packet->protoVersion.major, packet->protoVersion.minor); + errno = ENOSYS; + return -1; + } + + if (versionCompare(packet->uqmVersion.major, packet->uqmVersion.minor, + packet->uqmVersion.patch, NETPLAY_MIN_UQM_VERSION_MAJOR, + NETPLAY_MIN_UQM_VERSION_MINOR, NETPLAY_MIN_UQM_VERSION_PATCH) + < 0) { + sendAbort (conn, AbortReason_versionMismatch); + abortFeedback(conn, AbortReason_versionMismatch); + log_add(log_Error, "Remote side is running a version of UQM that " + "is too old (%d.%d.%d; %d.%d.%d is required).", + packet->uqmVersion.major, packet->uqmVersion.minor, + packet->uqmVersion.patch, NETPLAY_MIN_UQM_VERSION_MAJOR, + NETPLAY_MIN_UQM_VERSION_MINOR, NETPLAY_MIN_UQM_VERSION_PATCH); + errno = ENOSYS; + return -1; + } + + Netplay_remoteReady(conn); + + return 0; +} + +int +PacketHandler_Ping(NetConnection *conn, const Packet_Ping *packet) { + if (!testNetState(conn->state > NetState_init, PACKET_PING)) + return -1; // errno is set + + sendAck(conn, packet->id); + return 0; +} + +int +PacketHandler_Ack(NetConnection *conn, const Packet_Ack *packet) { + if (!testNetState(conn->state > NetState_init, PACKET_ACK)) + return -1; // errno is set + + (void) conn; + (void) packet; + return 0; +} + +// Convert the side indication relative to a remote party to +// a local player number. +static inline int +localSide(NetConnection *conn, NetplaySide side) { + if (side == NetplaySide_local) { + // "local" relative to the remote party. + return conn->player; + } + + return 1 - conn->player; +} + +int +PacketHandler_Ready(NetConnection *conn, const Packet_Ready *packet) { + if (conn->stateFlags.reset.localReset) + return 0; + if (conn->stateFlags.reset.remoteReset) { + errno = EBADMSG; + return -1; + } + + if (!testNetState(readyFlagsMeaningful(conn->state) && + !conn->stateFlags.ready.remoteReady, PACKET_READY)) + return -1; // errno is set + + Netplay_remoteReady(conn); + + (void) packet; + // Its contents is not interesting. + + return 0; +} + +int +PacketHandler_Fleet(NetConnection *conn, const Packet_Fleet *packet) { + uint16 numShips = ntoh16(packet->numShips); + size_t i; + size_t len; + int player; + BattleStateData *battleStateData; + + if (conn->stateFlags.reset.localReset) + return 0; + if (conn->stateFlags.reset.remoteReset) { + errno = EBADMSG; + return -1; + } + + if (!testNetState(conn->state == NetState_inSetup, PACKET_FLEET)) + return -1; // errno is set + + player = localSide(conn, (NetplaySide) packet->side); + + len = packetLength((const Packet *) packet); + if (sizeof packet + numShips * sizeof(packet->ships[0]) > len) { + // There is not enough room in the packet to contain all + // the ships it says it contains. + log_add(log_Warning, "Invalid fleet size. Specified size is %d, " + "actual size = %d", + numShips, (int) ((len - sizeof packet) / sizeof(packet->ships[0]))); + errno = EBADMSG; + return -1; + } + + battleStateData = (BattleStateData *) NetConnection_getStateData(conn); + + if (conn->stateFlags.handshake.localOk) { + Netplay_cancelConfirmation(conn); + confirmationCancelled(battleStateData->meleeState, conn->player); + } + + for (i = 0; i < numShips; i++) { + MeleeShip ship = (MeleeShip) packet->ships[i].ship; + FleetShipIndex index = (FleetShipIndex) packet->ships[i].index; + + if (!MeleeShip_valid(ship)) { + log_add (log_Warning, "Invalid ship type number %d (max = %d).\n", + ship, NUM_MELEE_SHIPS - 1); + errno = EBADMSG; + return -1; + } + + if (index >= MELEE_FLEET_SIZE) + { + log_add (log_Warning, "Invalid ship position number %d " + "(max = %d).\n", index, MELEE_FLEET_SIZE - 1); + errno = EBADMSG; + return -1; + } + + Melee_RemoteChange_ship (battleStateData->meleeState, conn, + player, index, ship); + } + + // Padding data may follow; it is ignored. + return 0; +} + +int +PacketHandler_TeamName(NetConnection *conn, const Packet_TeamName *packet) { + size_t nameLen; + int side; + BattleStateData *battleStateData; + + if (conn->stateFlags.reset.localReset) + return 0; + if (conn->stateFlags.reset.remoteReset) { + errno = EBADMSG; + return -1; + } + + if (!testNetState(conn->state == NetState_inSetup, PACKET_FLEET)) + return -1; // errno is set + + battleStateData = (BattleStateData *) NetConnection_getStateData(conn); + + if (conn->stateFlags.handshake.localOk) { + Netplay_cancelConfirmation(conn); + confirmationCancelled(battleStateData->meleeState, conn->player); + } + + side = localSide(conn, (NetplaySide) packet->side); + nameLen = packetLength((const Packet *) packet) + - sizeof (Packet_TeamName) - 1; + // The -1 is for not counting the terminating '\0'. + + { + char buf[MAX_TEAM_CHARS + 1]; + + if (nameLen > MAX_TEAM_CHARS) + nameLen = MAX_TEAM_CHARS; + memcpy (buf, (const char *) packet->name, nameLen); + buf[nameLen] = '\0'; + + Melee_RemoteChange_teamName(battleStateData->meleeState, conn, + side, buf); + } + + // Padding data may follow; it is ignored. + return 0; +} + +static void +handshakeComplete(NetConnection *conn) { + assert(!conn->stateFlags.handshake.localOk); + assert(!conn->stateFlags.handshake.remoteOk); + assert(!conn->stateFlags.handshake.canceling); + + assert(conn->state == NetState_inSetup); + NetConnection_setState(conn, NetState_preBattle); +} + +int +PacketHandler_Handshake0(NetConnection *conn, + const Packet_Handshake0 *packet) { + if (conn->stateFlags.reset.localReset) + return 0; + if (conn->stateFlags.reset.remoteReset) { + errno = EBADMSG; + return -1; + } + + if (!testNetState(handshakeMeaningful(conn->state) + && !conn->stateFlags.handshake.remoteOk, PACKET_HANDSHAKE0)) + return -1; // errno is set + + conn->stateFlags.handshake.remoteOk = true; + if (conn->stateFlags.handshake.localOk && + !conn->stateFlags.handshake.canceling) + sendHandshake1(conn); + + (void) packet; + // Its contents is not interesting. + + return 0; +} + +int +PacketHandler_Handshake1(NetConnection *conn, + const Packet_Handshake1 *packet) { + if (conn->stateFlags.reset.localReset) + return 0; + if (conn->stateFlags.reset.remoteReset) { + errno = EBADMSG; + return -1; + } + + if (!testNetState(handshakeMeaningful(conn->state) && + (conn->stateFlags.handshake.localOk || + conn->stateFlags.handshake.canceling), PACKET_HANDSHAKE1)) + return -1; // errno is set + + if (conn->stateFlags.handshake.canceling) { + conn->stateFlags.handshake.remoteOk = true; + } else { + bool remoteWasOk = conn->stateFlags.handshake.remoteOk; + + conn->stateFlags.handshake.localOk = false; + conn->stateFlags.handshake.remoteOk = false; + + if (!remoteWasOk) { + // Received Handshake1 without prior Handshake0. + // A Handshake0 is implied, but we still need to confirm + // it with a Handshake1. + sendHandshake1(conn); + } + + handshakeComplete(conn); + } + + (void) packet; + // Its contents is not interesting. + + return 0; +} + +int +PacketHandler_HandshakeCancel(NetConnection *conn, + const Packet_HandshakeCancel *packet) { + if (conn->stateFlags.reset.localReset) + return 0; + if (conn->stateFlags.reset.remoteReset) { + errno = EBADMSG; + return -1; + } + + if (!testNetState(handshakeMeaningful(conn->state) + && conn->stateFlags.handshake.remoteOk, PACKET_HANDSHAKECANCEL)) + return -1; // errno is set + + conn->stateFlags.handshake.remoteOk = false; + sendHandshakeCancelAck(conn); + + (void) packet; + // Its contents is not interesting. + + return 0; +} + +int +PacketHandler_HandshakeCancelAck(NetConnection *conn, + const Packet_HandshakeCancelAck *packet) { + if (conn->stateFlags.reset.localReset) + return 0; + if (conn->stateFlags.reset.remoteReset) { + errno = EBADMSG; + return -1; + } + + if (!testNetState(handshakeMeaningful(conn->state) + && conn->stateFlags.handshake.canceling, + PACKET_HANDSHAKECANCELACK)) + return -1; // errno is set + + conn->stateFlags.handshake.canceling = false; + if (conn->stateFlags.handshake.localOk) { + if (conn->stateFlags.handshake.remoteOk) { + sendHandshake1(conn); + } else + sendHandshake0(conn); + } + + (void) packet; + // Its contents is not interesting. + + return 0; +} + +int +PacketHandler_SeedRandom(NetConnection *conn, + const Packet_SeedRandom *packet) { + BattleStateData *battleStateData; + + if (conn->stateFlags.reset.localReset) + return 0; + if (conn->stateFlags.reset.remoteReset) { + errno = EBADMSG; + return -1; + } + + if (!testNetState(conn->state == NetState_preBattle && + !conn->stateFlags.discriminant, PACKET_SEEDRANDOM)) + return -1; // errno is set + + battleStateData = (BattleStateData *) NetConnection_getStateData(conn); + updateRandomSeed (battleStateData->meleeState, conn->player, + ntoh32(packet->seed)); + + conn->stateFlags.agreement.randomSeed = true; + return 0; +} + +int +PacketHandler_InputDelay(NetConnection *conn, + const Packet_InputDelay *packet) { + BattleStateData *battleStateData; + uint32 delay; + + if (conn->stateFlags.reset.localReset) + return 0; + if (conn->stateFlags.reset.remoteReset) { + errno = EBADMSG; + return -1; + } + + if (!testNetState(conn->state == NetState_preBattle, PACKET_INPUTDELAY)) + return -1; // errno is set + + battleStateData = (BattleStateData *) NetConnection_getStateData(conn); + delay = ntoh32(packet->delay); + if (delay > BATTLE_FRAME_RATE) { + log_add(log_Error, "NETPLAY: [%d] Received absurdly large " + "input delay value (%d).", conn->player, delay); + return -1; + } + conn->stateFlags.inputDelay = delay; + + return 0; +} + +int +PacketHandler_SelectShip(NetConnection *conn, + const Packet_SelectShip *packet) { + bool updateResult; + BattleStateData *battleStateData; + + if (conn->stateFlags.reset.localReset) + return 0; + if (conn->stateFlags.reset.remoteReset) { + errno = EBADMSG; + return -1; + } + + if (!testNetState(conn->state == NetState_selectShip, PACKET_SELECTSHIP)) + return -1; // errno is set + + battleStateData = (BattleStateData *) NetConnection_getStateData(conn); + updateResult = updateMeleeSelection(battleStateData->getMeleeState, + conn->player, ntoh16(packet->ship)); + if (!updateResult) + { + errno = EBADMSG; + return -1; + } + + return 0; +} + +int +PacketHandler_BattleInput(NetConnection *conn, + const Packet_BattleInput *packet) { + BATTLE_INPUT_STATE input; + BattleInputBuffer *bib; + + if (conn->stateFlags.reset.localReset) + return 0; + if (conn->stateFlags.reset.remoteReset) { + errno = EBADMSG; + return -1; + } + + if (!testNetState(conn->state == NetState_inBattle || + conn->state == NetState_endingBattle || + conn->state == NetState_endingBattle2, PACKET_BATTLEINPUT)) + return -1; // errno is set + + input = (BATTLE_INPUT_STATE) packet->state; + bib = getBattleInputBuffer(conn->player); + if (!BattleInputBuffer_push(bib, input)) { + // errno is set + return -1; + } + + return 0; +} + +int +PacketHandler_FrameCount(NetConnection *conn, + const Packet_FrameCount *packet) { + BattleStateData *battleStateData; + BattleFrameCounter frameCount; + + if (conn->stateFlags.reset.localReset) + return 0; + if (conn->stateFlags.reset.remoteReset) { + errno = EBADMSG; + return -1; + } + + if (!testNetState(conn->state == NetState_endingBattle, + PACKET_FRAMECOUNT)) + return -1; // errno is set + + frameCount = (BattleFrameCounter) ntoh32(packet->frameCount); +#ifdef NETPLAY_DEBUG + log_add(log_Debug, "NETPLAY: [%d] <== Received battleFrameCount %u.", + conn->player, (unsigned int) frameCount); +#endif + + battleStateData = (BattleStateData *) NetConnection_getStateData(conn); + if (frameCount > battleStateData->endFrameCount) + battleStateData->endFrameCount = frameCount; + Netplay_remoteReady(conn); + + return 0; +} + +int +PacketHandler_Checksum(NetConnection *conn, const Packet_Checksum *packet) { +#ifdef NETPLAY_CHECKSUM + uint32 frameNr; + uint32 checksum; + size_t delay; + size_t interval; +#endif + + if (conn->stateFlags.reset.localReset) + return 0; + if (conn->stateFlags.reset.remoteReset) { + errno = EBADMSG; + return -1; + } + + if (!testNetState(NetState_battleActive(conn->state), PACKET_CHECKSUM)) + return -1; // errno is set + +#ifdef NETPLAY_CHECKSUM + frameNr = ntoh32(packet->frameNr); + checksum = ntoh32(packet->checksum); + interval = NetConnection_getChecksumInterval(conn); + delay = getBattleInputDelay(); + + if (frameNr % interval != 0) { + log_add(log_Warning, "NETPLAY: [%d] <== Received checksum " + "for frame %u, while we only expect checksums on frames " + "divisable by %u -- discarding.", conn->player, + (unsigned int) frameNr, (unsigned int) interval); + return 0; + // No need to close the connection; checksums are not + // essential. + } + + // The checksum is sent at the beginning of a frame. + // If we're in frame n and have sent our input already, + // the remote side has got enough input to progress delay + 1 frames from + // frame n. The next frame is then n + delay + 1, for which we can + // receive a checksum. + if (frameNr > battleFrameCount + delay + 1) { + log_add(log_Warning, "NETPLAY: [%d] <== Received checksum " + "for a frame too far in the future (frame %u, current " + "is %u, input delay is %u) -- discarding.", conn->player, + (unsigned int) frameNr, (unsigned int) battleFrameCount, (unsigned int) delay); + return 0; + // No need to close the connection; checksums are not + // essential. + } + + // We can progress delay more frames after the last frame for which we + // received input. If we call that frame n, we can complete frames + // n through n + delay - 1. While we are waiting for the next input, + // in frame n + delay, we will first receive the checksum that the + // remote side sent at the start of frame n + 1. + // In this situation frameNr is n + 1, and battleFrameCount is + // n + delay. + if (frameNr + delay < battleFrameCount) { + log_add(log_Warning, "NETPLAY: [%d] <== Received checksum " + "for a frame too far in the past (frame %u, current " + "is %u, input delay is %u) -- discarding.", conn->player, + (unsigned int) frameNr, (unsigned int) battleFrameCount, (unsigned int) delay); + return 0; + // No need to close the connection; checksums are not + // essential. + } + + addRemoteChecksum(conn, frameNr, checksum); +#endif + +#ifndef NETPLAY_CHECKSUM + (void) packet; +#endif + return 0; +} + +int +PacketHandler_Abort(NetConnection *conn, const Packet_Abort *packet) { + abortFeedback(conn, packet->reason); + + return -1; + // Close connection. +} + +int +PacketHandler_Reset(NetConnection *conn, const Packet_Reset *packet) { + NetplayResetReason reason; + + if (!testNetState(!conn->stateFlags.reset.remoteReset, PACKET_RESET)) + return -1; // errno is set + + reason = ntoh16(packet->reason); + + Netplay_remoteReset(conn, reason); + return 0; +} + + |