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Add TCP_SEQ_BETWEEN macro for comparing a range of sequence numbers

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This commit is contained in:
kieranm 2004-09-12 15:56:12 +00:00
parent 89abd1f58e
commit a3d27e30e0
2 changed files with 80 additions and 66 deletions
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135
src/core/tcp_in.c
View File

@ -506,9 +506,11 @@ tcp_process(struct tcp_pcb *pcb)
acceptable = 1;
}
} else {
if (TCP_SEQ_GEQ(seqno, pcb->rcv_nxt) &&
TCP_SEQ_LEQ(seqno, pcb->rcv_nxt + pcb->rcv_wnd)) {
acceptable = 1;
/*if (TCP_SEQ_GEQ(seqno, pcb->rcv_nxt) &&
TCP_SEQ_LEQ(seqno, pcb->rcv_nxt + pcb->rcv_wnd)) {
*/
if(TCP_SEQ_BETWEEN(seqno, pcb->rcv_nxt, pcb->rcv_nxt+pcb->rcv_wnd)){
acceptable = 1;
}
}
@ -562,8 +564,9 @@ tcp_process(struct tcp_pcb *pcb)
case SYN_RCVD:
if (flags & TCP_ACK &&
!(flags & TCP_RST)) {
if (TCP_SEQ_LT(pcb->lastack, ackno) &&
TCP_SEQ_LEQ(ackno, pcb->snd_nxt)) {
/*if (TCP_SEQ_LT(pcb->lastack, ackno) &&
TCP_SEQ_LEQ(ackno, pcb->snd_nxt)) { */
if(TCP_SEQ_BETWEEN(ackno, pcb->lastack+1, pcb->snd_nxt))
pcb->state = ESTABLISHED;
LWIP_DEBUGF(TCP_DEBUG, ("TCP connection established %u -> %u.\n", inseg.tcphdr->src, inseg.tcphdr->dest));
#if LWIP_CALLBACK_API
@ -732,8 +735,10 @@ tcp_receive(struct tcp_pcb *pcb)
LWIP_DEBUGF(TCP_FR_DEBUG, ("tcp_receive: dupack averted %lu %lu\n",
pcb->snd_wl1 + pcb->snd_wnd, right_wnd_edge));
}
} else if (TCP_SEQ_LT(pcb->lastack, ackno) &&
TCP_SEQ_LEQ(ackno, pcb->snd_max)) {
} else
/*if (TCP_SEQ_LT(pcb->lastack, ackno) &&
TCP_SEQ_LEQ(ackno, pcb->snd_max)) { */
if(TCP_SEQ_BETWEEN(ackno, pcb->lastack+1, pcb->snd_max)){
/* We come here when the ACK acknowledges new data. */
/* Reset the "IN Fast Retransmit" flag, since we are no longer
@ -818,12 +823,13 @@ tcp_receive(struct tcp_pcb *pcb)
segments on the unsent queue when performing retransmit */
#if 0
while (pcb->unsent != NULL &&
TCP_SEQ_LEQ(ntohl(pcb->unsent->tcphdr->seqno) + TCP_TCPLEN(pcb->unsent),
ackno) &&
TCP_SEQ_LEQ(ackno, pcb->snd_max)) {
/*TCP_SEQ_LEQ(ntohl(pcb->unsent->tcphdr->seqno) + TCP_TCPLEN(pcb->unsent), ackno) &&
TCP_SEQ_LEQ(ackno, pcb->snd_max)*/
TCP_SEQ_BETWEEN(ackno, ntohl(pcb->unsent->tcphdr->seqno) + TCP_TCPLEN(pcb->unsent), pcb->snd_max)
) {
LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: removing %lu:%lu from pcb->unsent\n",
ntohl(pcb->unsent->tcphdr->seqno), ntohl(pcb->unsent->tcphdr->seqno) +
TCP_TCPLEN(pcb->unsent)));
ntohl(pcb->unsent->tcphdr->seqno), ntohl(pcb->unsent->tcphdr->seqno) +
TCP_TCPLEN(pcb->unsent)));
next = pcb->unsent;
pcb->unsent = pcb->unsent->next;
@ -903,52 +909,54 @@ tcp_receive(struct tcp_pcb *pcb)
this if the sequence number of the incoming segment is less
than rcv_nxt, and the sequence number plus the length of the
segment is larger than rcv_nxt. */
if (TCP_SEQ_LT(seqno, pcb->rcv_nxt)){
if (TCP_SEQ_LT(pcb->rcv_nxt, seqno + tcplen)) {
/* Trimming the first edge is done by pushing the payload
pointer in the pbuf downwards. This is somewhat tricky since
we do not want to discard the full contents of the pbuf up to
the new starting point of the data since we have to keep the
TCP header which is present in the first pbuf in the chain.
/* if (TCP_SEQ_LT(seqno, pcb->rcv_nxt)){
if (TCP_SEQ_LT(pcb->rcv_nxt, seqno + tcplen)) {*/
if(TCP_SEQ_BETWEEN(pcb->rcv_nxt, seqno+1, seqno+tcplen-1)){
/* Trimming the first edge is done by pushing the payload
pointer in the pbuf downwards. This is somewhat tricky since
we do not want to discard the full contents of the pbuf up to
the new starting point of the data since we have to keep the
TCP header which is present in the first pbuf in the chain.
What is done is really quite a nasty hack: the first pbuf in
the pbuf chain is pointed to by inseg.p. Since we need to be
able to deallocate the whole pbuf, we cannot change this
inseg.p pointer to point to any of the later pbufs in the
chain. Instead, we point the ->payload pointer in the first
pbuf to data in one of the later pbufs. We also set the
inseg.data pointer to point to the right place. This way, the
->p pointer will still point to the first pbuf, but the
->p->payload pointer will point to data in another pbuf.
What is done is really quite a nasty hack: the first pbuf in
the pbuf chain is pointed to by inseg.p. Since we need to be
able to deallocate the whole pbuf, we cannot change this
inseg.p pointer to point to any of the later pbufs in the
chain. Instead, we point the ->payload pointer in the first
pbuf to data in one of the later pbufs. We also set the
inseg.data pointer to point to the right place. This way, the
->p pointer will still point to the first pbuf, but the
->p->payload pointer will point to data in another pbuf.
After we are done with adjusting the pbuf pointers we must
adjust the ->data pointer in the seg and the segment
length.*/
After we are done with adjusting the pbuf pointers we must
adjust the ->data pointer in the seg and the segment
length.*/
off = pcb->rcv_nxt - seqno;
p = inseg.p;
if (inseg.p->len < off) {
new_tot_len = inseg.p->tot_len - off;
while (p->len < off) {
off -= p->len;
/* KJM following line changed (with addition of new_tot_len var)
to fix bug #9076
inseg.p->tot_len -= p->len; */
p->tot_len = new_tot_len;
p->len = 0;
p = p->next;
}
pbuf_header(p, -off);
} else {
pbuf_header(inseg.p, -off);
off = pcb->rcv_nxt - seqno;
p = inseg.p;
if (inseg.p->len < off) {
new_tot_len = inseg.p->tot_len - off;
while (p->len < off) {
off -= p->len;
/* KJM following line changed (with addition of new_tot_len var)
to fix bug #9076
inseg.p->tot_len -= p->len; */
p->tot_len = new_tot_len;
p->len = 0;
p = p->next;
}
/* KJM following line changed to use p->payload rather than inseg->p->payload
to fix bug #9076 */
inseg.dataptr = p->payload;
inseg.len -= pcb->rcv_nxt - seqno;
inseg.tcphdr->seqno = seqno = pcb->rcv_nxt;
pbuf_header(p, -off);
} else {
pbuf_header(inseg.p, -off);
}
else{
/* KJM following line changed to use p->payload rather than inseg->p->payload
to fix bug #9076 */
inseg.dataptr = p->payload;
inseg.len -= pcb->rcv_nxt - seqno;
inseg.tcphdr->seqno = seqno = pcb->rcv_nxt;
}
else{
if(TCP_SEQ_LT(seqno, pcb->rcv_nxt)){
/* the whole segment is < rcv_nxt */
/* must be a duplicate of a packet that has already been correctly handled */
@ -960,8 +968,9 @@ tcp_receive(struct tcp_pcb *pcb)
/* The sequence number must be within the window (above rcv_nxt
and below rcv_nxt + rcv_wnd) in order to be further
processed. */
if (TCP_SEQ_GEQ(seqno, pcb->rcv_nxt) &&
TCP_SEQ_LT(seqno, pcb->rcv_nxt + pcb->rcv_wnd)) {
/*if (TCP_SEQ_GEQ(seqno, pcb->rcv_nxt) &&
TCP_SEQ_LT(seqno, pcb->rcv_nxt + pcb->rcv_wnd)) {*/
if(TCP_SEQ_BETWEEN(seqno, pcb->rcv_nxt, pcb->rcv_nxt + pcb->rcv_wnd - 1)){
if (pcb->rcv_nxt == seqno) {
/* The incoming segment is the next in sequence. We check if
we have to trim the end of the segment and update rcv_nxt
@ -1115,8 +1124,10 @@ tcp_receive(struct tcp_pcb *pcb)
}
break;
}
} else if (TCP_SEQ_LT(prev->tcphdr->seqno, seqno) &&
TCP_SEQ_LT(seqno, next->tcphdr->seqno)) {
} else
/*if (TCP_SEQ_LT(prev->tcphdr->seqno, seqno) &&
TCP_SEQ_LT(seqno, next->tcphdr->seqno)) {*/
if(TCP_SEQ_BETWEEN(seqno, prev->tcphdr->seqno, next->tcphdr->seqno-1)){
/* The sequence number of the incoming segment is in
between the sequence numbers of the previous and
the next segment on ->ooseq. We trim and insert the
@ -1163,16 +1174,18 @@ tcp_receive(struct tcp_pcb *pcb)
}
} else {
if (TCP_SEQ_GT(pcb->rcv_nxt, seqno) ||
TCP_SEQ_GEQ(seqno, pcb->rcv_nxt + pcb->rcv_wnd)) {
/*if (TCP_SEQ_GT(pcb->rcv_nxt, seqno) ||
TCP_SEQ_GEQ(seqno, pcb->rcv_nxt + pcb->rcv_wnd)) {*/
if(!TCP_SEQ_BETWEEN(seqno, pcb->rcv_nxt, pcb->rcv_nxt + pcb->rcv_wnd-1)){
tcp_ack_now(pcb);
}
}
} else {
/* Segments with length 0 is taken care of here. Segments that
fall out of the window are ACKed. */
if (TCP_SEQ_GT(pcb->rcv_nxt, seqno) ||
TCP_SEQ_GEQ(seqno, pcb->rcv_nxt + pcb->rcv_wnd)) {
/*if (TCP_SEQ_GT(pcb->rcv_nxt, seqno) ||
TCP_SEQ_GEQ(seqno, pcb->rcv_nxt + pcb->rcv_wnd)) {*/
if(!TCP_SEQ_BETWEEN(seqno, pcb->rcv_nxt, pcb->rcv_nxt + pcb->rcv_wnd-1)){
tcp_ack_now(pcb);
}
}

3
src/include/lwip/tcp.h
View File

@ -112,7 +112,8 @@ void tcp_rexmit (struct tcp_pcb *pcb);
#define TCP_SEQ_LEQ(a,b) ((s32_t)((a)-(b)) <= 0)
#define TCP_SEQ_GT(a,b) ((s32_t)((a)-(b)) > 0)
#define TCP_SEQ_GEQ(a,b) ((s32_t)((a)-(b)) >= 0)
/* is b<=a<=c? */
#define TCP_SEQ_BETWEEN(a,b,c) ((c)-(b) >= (a)-(b))
#define TCP_FIN 0x01U
#define TCP_SYN 0x02U
#define TCP_RST 0x04U