Another fix for bug #26251: RST process in TIME_WAIT TCP state

This commit is contained in:
goldsimon 2009-10-25 11:45:11 +00:00
parent 0319c1cf90
commit ae2dd38e0d
2 changed files with 28 additions and 5 deletions

View File

@ -43,12 +43,12 @@ HISTORY
++ Bugfixes:
2009-10-25: Simon Goldschmidt
* tcp_in.c: Fixed bug #26251: RST process in TIME_WAIT TCP state
2009-10-23: Simon Goldschmidt (David Empson)
* tcp.c: Fixed bug #27783: Silly window avoidance for small window sizes
2009-10-22: Simon Goldschmidt
* tcp_in.c: Fixed bug #26251: RST process in TIME_WAIT TCP state
2009-10-21: Simon Goldschmidt
* tcp_in.c: Fixed bug #27215: TCP sent() callback gives leading and
trailing 1 byte len (SYN/FIN)

View File

@ -480,9 +480,32 @@ tcp_listen_input(struct tcp_pcb_listen *pcb)
static err_t
tcp_timewait_input(struct tcp_pcb *pcb)
{
u16_t flags = TCPH_FLAGS(tcphdr);
/* RFC 1337: in TIME_WAIT, ignore RST and ACK FINs + any 'acceptable' segments */
if (((flags & TCP_RST) == 0) && ((flags & TCP_FIN) || (tcplen > 0))) {
/* RFC 793 3.9 Event Processing - Segment Arrives:
* - first check sequence number - we skip that one in TIME_WAIT (always
* acceptable since we only send ACKs)
* - second check the RST bit (... return) */
if (flags & TCP_RST) {
return ERR_OK;
}
/* - fourth, check the SYN bit, */
if (flags & TCP_SYN) {
/* If an incoming segment is not acceptable, an acknowledgment
should be sent in reply */
if (TCP_SEQ_BETWEEN(seqno, pcb->rcv_nxt, pcb->rcv_nxt+pcb->rcv_wnd)) {
/* If the SYN is in the window it is an error, send a reset */
tcp_rst(ackno, seqno + tcplen, &(iphdr->dest), &(iphdr->src),
tcphdr->dest, tcphdr->src);
return ERR_OK;
}
} else if (flags & TCP_FIN) {
/* - eighth, check the FIN bit: Remain in the TIME-WAIT state.
Restart the 2 MSL time-wait timeout.*/
pcb->tmr = tcp_ticks;
}
if ((tcplen > 0)) {
/* Acknowledge data, FIN or out-of-window SYN */
pcb->flags |= TF_ACK_NOW;
return tcp_output(pcb);
}