Commit 6bf20147 authored by Tim Newsome's avatar Tim Newsome Committed by Daniel Stenberg
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TFTP: Work around tftpd-hpa upload bug 

tftpd-hpa has a bug where it will send an incorrect ack when the block
counter wraps and tftp options have been sent. Work around that by
accepting an ack for 65535 when we're expecting one for 0.
parent a10f5b34

lib/tftp.c

+7 −1
Original line number Original line Diff line number Diff line
@@ -719,7 +719,13 @@ static CURLcode tftp_tx(tftp_state_data_t *state, tftp_event_t event) 
       /* Ack the packet */

       /* Ack the packet */

       rblock = getrpacketblock(&state->rpacket);

       rblock = getrpacketblock(&state->rpacket);





       if(rblock != state->block) {

       if(rblock != state->block &&

             /* There's a bug in tftpd-hpa that causes it to send us an ack for

              * 65535 when the block number wraps to 0. So when we're expecting

              * 0, also accept 65535. See

              * http://syslinux.zytor.com/archives/2010-September/015253.html

              * */

             !(state->block == 0 && rblock == 65535)) {

          /* This isn't the expected block.  Log it and up the retry counter */

          /* This isn't the expected block.  Log it and up the retry counter */

          infof(data, "Received ACK for block %d, expecting %d\n",

          infof(data, "Received ACK for block %d, expecting %d\n",

                rblock, state->block);

                rblock, state->block);