Git-Mirrors/RetroShare
1
0
Fork 0
mirror of https://github.com/RetroShare/RetroShare.git synced 2025-02-17 21:34:10 -05:00
Code Issues Actions Packages Projects Releases Wiki Activity

Bugfixes for TcoOnUdp:

Browse Source 
* Reduce Maximum Transmission size from 1500 -> 1000.  
	This is the cause of Failed Connections. It looks like UDP packets are being truncated from 1520 -> 1492 bytes.
	and this is killing the TCP protocol. Windows is the main suspect. UDP packets this large are liable to get fragmented anyway.
	We will start at 1000, verify that connections are okay, then start increasing this parameter.
	There is up to 64 bytes of Headers (IP + UDP + Relay + TOU), so 1400 + 64 = 1464 is below the 1492 cutoff. This is the target!
 * Switch to RSRandom for Sequence numbers. rand() is rubbish on Windows.
 * Added code to handle Larger Packets coming in (e.g. 1500 Bytes input, now that Max Size is 1000).

NB: The code is here needs to be optimised, there are excessive numbers of malloc(), new() & memcpy(), which should be removed.



git-svn-id: http://svn.code.sf.net/p/retroshare/code/trunk@4482 b45a01b8-16f6-495d-af2f-9b41ad6348cc
This commit is contained in:
drbob 2011-07-20 18:37:21 +00:00
parent a683b64311
commit d0f52f1d5f
2 changed files with 107 additions and 20 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

119
libretroshare/src/tcponudp/tcpstream.cc
View File

@ -40,6 +40,9 @@
/* Debugging for STATE change, and Startup SYNs */
#include "util/rsdebug.h"
#include "util/rsrandom.h"
const int rstcpstreamzone = 28455;
@ -62,7 +65,7 @@ int setupBinaryCheck(std::string fname);
static const uint32 kMaxQueueSize = 100;
static const uint32 kMaxPktRetransmit = 20;
static const uint32 kMaxSynPktRetransmit = 1000; // up to 1000 (16 min?) startup
static const uint32 kMaxSynPktRetransmit = 100; // 100 => 200secs = over 3 minutes startup
static const int TCP_STD_TTL = 64;
static const int TCP_DEFAULT_FIREWALL_TTL = 4;
@ -1462,6 +1465,13 @@ int TcpStream::incoming_Established(TcpPacket *pkt)
* make sure that the sequence number is within the correct range.
*/
#ifdef DEBUG_TCP_STREAM
std::cerr << "TcpStream::incoming_Established() ";
std::cerr << " Pkt->seqno: " << std::hex << pkt->seqno;
std::cerr << " Pkt->datasize: " << std::hex << pkt->datasize;
std::cerr << std::dec << std::endl;
#endif
if ((!isOldSequence(pkt->seqno, inAckno)) && // seq >= inAckno
isOldSequence(pkt->seqno, inAckno + maxWinSize)) // seq < inAckno + maxWinSize.
{
@ -1471,11 +1481,16 @@ int TcpStream::incoming_Established(TcpPacket *pkt)
#endif
if (pkt->hasAck())
{
outAcked = pkt->ackno;
#ifdef DEBUG_TCP_STREAM
std::cerr << "\tUpdating OutAcked to: " << outAcked;
std::cerr << std::endl;
if (outAcked != pkt->ackno)
{
std::cerr << "TcpStream::incoming_Established() valid Packet Seqno & new Ackno.";
std::cerr << std::endl;
std::cerr << "\tUpdating OutAcked to: " << outAcked;
std::cerr << std::endl;
}
#endif
outAcked = pkt->ackno;
}
outWinSize = pkt->winsize;
@ -1487,10 +1502,26 @@ int TcpStream::incoming_Established(TcpPacket *pkt)
}
else
{
/* what we do! */
/* what we do! (This is actually okay - and happens occasionally) */
#ifdef DEBUG_TCP_STREAM
std::cerr << "TcpStream::incoming_Established() ERROR out-of-range Packet Seqno.";
std::cerr << std::endl;
std::cerr << "\t Pkt->SeqNo: " << std::hex << pkt->seqno;
std::cerr << std::endl;
std::cerr << "\t inAckno: " << std::hex << inAckno;
std::cerr << std::endl;
std::cerr << "\t inAckno + maxWinSize: " << std::hex << inAckno + maxWinSize;
std::cerr << std::endl;
std::cerr << "\t outAcked: " << std::hex << outAcked;
std::cerr << std::endl;
std::cerr << "\t Pkt->SeqNo: " << std::hex << pkt->seqno;
std::cerr << std::dec << std::endl;
std::cerr << "\t !isOldSequence(pkt->seqno, inAckno): " << (!isOldSequence(pkt->seqno, inAckno));
std::cerr << std::endl;
std::cerr << "\t isOldSequence(pkt->seqno, inAckno + maxWinSize): " << isOldSequence(pkt->seqno, inAckno + maxWinSize);
std::cerr << std::endl;
std::cerr << std::endl;
std::cerr << "TcpStream::incoming_Established() Sending Ack to update Peer";
std::cerr << std::endl;
#endif
@ -1530,13 +1561,18 @@ int TcpStream::check_InPkts()
for(it = inPkt.begin(); (!found) && (it != inPkt.end());)
{
#ifdef DEBUG_TCP_STREAM
std::cerr << "Checking expInAck: " << inAckno << " vs: " << (*it)->seqno << std::endl;
std::cerr << "Checking expInAck: " << std::hex << inAckno;
std::cerr << " vs: " << std::hex << (*it)->seqno << std::dec << std::endl;
#endif
pkt = *it;
if ((*it)->seqno == inAckno)
{
//std::cerr << "\tFOUND MATCH!";
//std::cerr << std::endl;
found = true;
inPkt.erase(it);
it = inPkt.erase(it);
}
@ -1545,8 +1581,11 @@ int TcpStream::check_InPkts()
else if (isOldSequence((*it)->seqno, inAckno))
{
#ifdef DEBUG_TCP_STREAM
std::cerr << "Discarding Old Packet expAck: " << inAckno;
std::cerr << " seqno: " << (*it)->seqno << std::endl;
std::cerr << "Discarding Old Packet expAck: " << std::hex << inAckno;
std::cerr << " seqno: " << std::hex << (*it)->seqno;
std::cerr << " pkt->size: " << std::hex << (*it)->datasize;
std::cerr << " pkt->seqno+size: " << std::hex << (*it)->seqno + (*it)->datasize;
std::cerr << std::dec << std::endl;
#endif
/* discard */
@ -1569,9 +1608,18 @@ int TcpStream::check_InPkts()
}
#endif
#ifdef DEBUG_TCP_STREAM
std::cerr << "TcpStream::check_inPkts() Updating inAckno from: " << std::hex << inAckno;
#endif
/* update ack number - let it rollover */
inAckno = pkt->seqno + pkt->datasize;
#ifdef DEBUG_TCP_STREAM
std::cerr << " to: " << std::hex << inAckno;
std::cerr << std::dec << std::endl;
#endif
/* XXX This shouldn't be here, as it prevents
* the Ack being used until the packet is.
* This means that a dropped packet will stop traffic in both
@ -1588,7 +1636,19 @@ int TcpStream::check_InPkts()
#ifdef DEBUG_TCP_STREAM
std::cerr << "TcpStream::check_inPkts() ERROR Ack Not Already Used!";
std::cerr << std::endl;
std::cerr << "\t Pkt->ackno: " << std::hex << pkt->ackno;
std::cerr << std::endl;
std::cerr << "\t outAcked: " << std::hex << outAcked;
std::cerr << std::endl;
std::cerr << "\t Pkt->winsize: " << std::hex << pkt->winsize;
std::cerr << std::endl;
std::cerr << "\t outWinSize: " << std::hex << outWinSize;
std::cerr << std::endl;
std::cerr << "\t isOldSequence(outAcked, pkt->ackno): " << isOldSequence(outAcked, pkt->ackno);
std::cerr << std::endl;
std::cerr << std::endl;
#endif
outAcked = pkt->ackno;
outWinSize = pkt->winsize;
@ -1632,15 +1692,26 @@ int TcpStream::check_InPkts()
int remSpace = MAX_SEG - outSizeNet;
memcpy((void *) &(db->data[outSizeNet]), (void *) pkt->data, remSpace);
/* remove any remaining to outDataNet */
outSizeNet = pkt->datasize - remSpace;
if (outSizeNet > 0)
{
memcpy((void *) outDataNet, (void *) &(pkt->data[remSpace]), outSizeNet);
}
/* push packet onto queue */
outQueue.push_back(db);
/* any big chunks that will take up a full dataBuffer */
int remData = pkt->datasize - remSpace;
while(remData >= MAX_SEG)
{
db = new dataBuffer();
memcpy((void *) db->data, (void *) &(pkt->data[remSpace]), MAX_SEG);
remData -= MAX_SEG;
outQueue.push_back(db);
}
/* remove any remaining to outDataNet */
outSizeNet = remData;
if (outSizeNet > 0)
{
memcpy((void *) outDataNet, (void *) &(pkt->data[pkt->datasize - remData]), outSizeNet);
}
}
/* can allow more in! - update inWinSize */
@ -2035,11 +2106,19 @@ int TcpStream::retrans()
/* catch excessive retransmits
* - Allow Syn case more....
* - if not SYN or TTL has reached STD then timeout quickly.
* OLD 2nd Logic (below) has been replaced with lower logic.
* (((!pkt->hasSyn()) || (TCP_STD_TTL == getTTL()))
* && (pkt->retrans > kMaxPktRetransmit)))
* Problem was that the retransmit of Syn packet had STD_TTL, and was triggering Close (and SeqNo change).
* It seemed to work anyway.... But might cause coonnection failures. Will reduce the MaxSyn Retransmit
* so something more reasonable as well.
* ((!pkt->hasSyn()) && (pkt->retrans > kMaxPktRetransmit)))
*/
if ((pkt->hasSyn() && (pkt->retrans > kMaxSynPktRetransmit)) ||
(((!pkt->hasSyn()) || (TCP_STD_TTL == getTTL()))
&& (pkt->retrans > kMaxPktRetransmit)))
((!pkt->hasSyn()) && (pkt->retrans > kMaxPktRetransmit)))
{
/* too many attempts close stream */
#ifdef DEBUG_TCP_STREAM
@ -2431,8 +2510,10 @@ int TcpStream::send()
uint32 TcpStream::genSequenceNo()
{
return RSRandom::random_u32();
//return 1000; // TCP_MAX_SEQ - 1000; //1000; //(rand() - 100000) + time(NULL) % 100000;
return (rand() - 100000) + time(NULL) % 100000;
//return (rand() - 100000) + time(NULL) % 100000;
}

8
libretroshare/src/tcponudp/tcpstream.h
View File

@ -38,7 +38,13 @@
#include "tcppacket.h"
#include "udppeer.h"
#define MAX_SEG 1500
// WINDOWS doesn't like UDP packets bigger than 1492 (truncates them).
// We have up to 64 bytes of headers: 28(udp) + 16(relay) + 20(tou) = 64 bytes.
// 64 bytes + 1400 = 1464, leaves a small margin, but close to maximum throughput.
//#define MAX_SEG 1400
// We are going to start at 1000 (to avoid any fragmentation, and work up).
#define MAX_SEG 1000
#define TCP_MAX_SEQ UINT_MAX
#define TCP_MAX_WIN 65500
#define TCP_ALIVE_TIMEOUT 15 /* 15 sec ... < 20 sec UDP state limit on some firewalls */