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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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49
src/core/tcp_in.c
View File

@ -506,8 +506,10 @@ tcp_process(struct tcp_pcb *pcb)
acceptable = 1; acceptable = 1;
} }
} else { } else {
if (TCP_SEQ_GEQ(seqno, pcb->rcv_nxt) && /*if (TCP_SEQ_GEQ(seqno, pcb->rcv_nxt) &&
TCP_SEQ_LEQ(seqno, pcb->rcv_nxt + pcb->rcv_wnd)) { 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; acceptable = 1;
} }
} }
@ -562,8 +564,9 @@ tcp_process(struct tcp_pcb *pcb)
case SYN_RCVD: case SYN_RCVD:
if (flags & TCP_ACK && if (flags & TCP_ACK &&
!(flags & TCP_RST)) { !(flags & TCP_RST)) {
if (TCP_SEQ_LT(pcb->lastack, ackno) && /*if (TCP_SEQ_LT(pcb->lastack, ackno) &&
TCP_SEQ_LEQ(ackno, pcb->snd_nxt)) { TCP_SEQ_LEQ(ackno, pcb->snd_nxt)) { */
if(TCP_SEQ_BETWEEN(ackno, pcb->lastack+1, pcb->snd_nxt))
pcb->state = ESTABLISHED; pcb->state = ESTABLISHED;
LWIP_DEBUGF(TCP_DEBUG, ("TCP connection established %u -> %u.\n", inseg.tcphdr->src, inseg.tcphdr->dest)); LWIP_DEBUGF(TCP_DEBUG, ("TCP connection established %u -> %u.\n", inseg.tcphdr->src, inseg.tcphdr->dest));
#if LWIP_CALLBACK_API #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", LWIP_DEBUGF(TCP_FR_DEBUG, ("tcp_receive: dupack averted %lu %lu\n",
pcb->snd_wl1 + pcb->snd_wnd, right_wnd_edge)); pcb->snd_wl1 + pcb->snd_wnd, right_wnd_edge));
} }
} else if (TCP_SEQ_LT(pcb->lastack, ackno) && } else
TCP_SEQ_LEQ(ackno, pcb->snd_max)) { /*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. */ /* We come here when the ACK acknowledges new data. */
/* Reset the "IN Fast Retransmit" flag, since we are no longer /* Reset the "IN Fast Retransmit" flag, since we are no longer
@ -818,9 +823,10 @@ tcp_receive(struct tcp_pcb *pcb)
segments on the unsent queue when performing retransmit */ segments on the unsent queue when performing retransmit */
#if 0 #if 0
while (pcb->unsent != NULL && while (pcb->unsent != NULL &&
TCP_SEQ_LEQ(ntohl(pcb->unsent->tcphdr->seqno) + TCP_TCPLEN(pcb->unsent), /*TCP_SEQ_LEQ(ntohl(pcb->unsent->tcphdr->seqno) + TCP_TCPLEN(pcb->unsent), ackno) &&
ackno) && TCP_SEQ_LEQ(ackno, pcb->snd_max)*/
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", LWIP_DEBUGF(TCP_INPUT_DEBUG, ("tcp_receive: removing %lu:%lu from pcb->unsent\n",
ntohl(pcb->unsent->tcphdr->seqno), ntohl(pcb->unsent->tcphdr->seqno) + ntohl(pcb->unsent->tcphdr->seqno), ntohl(pcb->unsent->tcphdr->seqno) +
TCP_TCPLEN(pcb->unsent))); TCP_TCPLEN(pcb->unsent)));
@ -903,8 +909,9 @@ tcp_receive(struct tcp_pcb *pcb)
this if the sequence number of the incoming segment is less this if the sequence number of the incoming segment is less
than rcv_nxt, and the sequence number plus the length of the than rcv_nxt, and the sequence number plus the length of the
segment is larger than rcv_nxt. */ segment is larger than rcv_nxt. */
if (TCP_SEQ_LT(seqno, pcb->rcv_nxt)){ /* if (TCP_SEQ_LT(seqno, pcb->rcv_nxt)){
if (TCP_SEQ_LT(pcb->rcv_nxt, seqno + tcplen)) { 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 /* Trimming the first edge is done by pushing the payload
pointer in the pbuf downwards. This is somewhat tricky since pointer in the pbuf downwards. This is somewhat tricky since
we do not want to discard the full contents of the pbuf up to we do not want to discard the full contents of the pbuf up to
@ -949,6 +956,7 @@ tcp_receive(struct tcp_pcb *pcb)
inseg.tcphdr->seqno = seqno = pcb->rcv_nxt; inseg.tcphdr->seqno = seqno = pcb->rcv_nxt;
} }
else{ else{
if(TCP_SEQ_LT(seqno, pcb->rcv_nxt)){
/* the whole segment is < rcv_nxt */ /* the whole segment is < rcv_nxt */
/* must be a duplicate of a packet that has already been correctly handled */ /* 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 /* The sequence number must be within the window (above rcv_nxt
and below rcv_nxt + rcv_wnd) in order to be further and below rcv_nxt + rcv_wnd) in order to be further
processed. */ processed. */
if (TCP_SEQ_GEQ(seqno, pcb->rcv_nxt) && /*if (TCP_SEQ_GEQ(seqno, pcb->rcv_nxt) &&
TCP_SEQ_LT(seqno, pcb->rcv_nxt + pcb->rcv_wnd)) { 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) { if (pcb->rcv_nxt == seqno) {
/* The incoming segment is the next in sequence. We check if /* The incoming segment is the next in sequence. We check if
we have to trim the end of the segment and update rcv_nxt we have to trim the end of the segment and update rcv_nxt
@ -1115,8 +1124,10 @@ tcp_receive(struct tcp_pcb *pcb)
} }
break; break;
} }
} else if (TCP_SEQ_LT(prev->tcphdr->seqno, seqno) && } else
TCP_SEQ_LT(seqno, next->tcphdr->seqno)) { /*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 /* The sequence number of the incoming segment is in
between the sequence numbers of the previous and between the sequence numbers of the previous and
the next segment on ->ooseq. We trim and insert the the next segment on ->ooseq. We trim and insert the
@ -1163,16 +1174,18 @@ tcp_receive(struct tcp_pcb *pcb)
} }
} else { } else {
if (TCP_SEQ_GT(pcb->rcv_nxt, seqno) || /*if (TCP_SEQ_GT(pcb->rcv_nxt, seqno) ||
TCP_SEQ_GEQ(seqno, pcb->rcv_nxt + pcb->rcv_wnd)) { 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); tcp_ack_now(pcb);
} }
} }
} else { } else {
/* Segments with length 0 is taken care of here. Segments that /* Segments with length 0 is taken care of here. Segments that
fall out of the window are ACKed. */ fall out of the window are ACKed. */
if (TCP_SEQ_GT(pcb->rcv_nxt, seqno) || /*if (TCP_SEQ_GT(pcb->rcv_nxt, seqno) ||
TCP_SEQ_GEQ(seqno, pcb->rcv_nxt + pcb->rcv_wnd)) { 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); 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_LEQ(a,b) ((s32_t)((a)-(b)) <= 0)
#define TCP_SEQ_GT(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) #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_FIN 0x01U
#define TCP_SYN 0x02U #define TCP_SYN 0x02U
#define TCP_RST 0x04U #define TCP_RST 0x04U