On 2012-09-10 20:05, Hervé Poussineau wrote:
> RFC 1350 does not mention block count roll-over. However, a lot of TFTP
> servers
> implement it to be able to transmit big files, so do it also.
>
> Current block size is 512 bytes, so TFTP files were limited to 32 MB.
>
> Signed-off-by: Hervé Poussineau <hpous...@reactos.org>
> Reviewed-by: Aurelien Jarno <aurel...@aurel32.net>
> ---
> slirp/tftp.c | 9 +++++----
> slirp/tftp.h | 1 +
> 2 files changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/slirp/tftp.c b/slirp/tftp.c
> index 520dbd6..75c9030 100644
> --- a/slirp/tftp.c
> +++ b/slirp/tftp.c
> @@ -97,7 +97,7 @@ static int tftp_session_find(Slirp *slirp, struct tftp_t
> *tp)
> return -1;
> }
>
> -static int tftp_read_data(struct tftp_session *spt, uint16_t block_nr,
> +static int tftp_read_data(struct tftp_session *spt, uint32_t block_nr,
> uint8_t *buf, int len)
> {
> int bytes_read = 0;
> @@ -198,7 +198,7 @@ out:
> }
>
> static int tftp_send_data(struct tftp_session *spt,
> - uint16_t block_nr,
> + uint32_t block_nr,
> struct tftp_t *recv_tp)
> {
> struct sockaddr_in saddr, daddr;
> @@ -223,7 +223,7 @@ static int tftp_send_data(struct tftp_session *spt,
> m->m_data += sizeof(struct udpiphdr);
>
> tp->tp_op = htons(TFTP_DATA);
> - tp->x.tp_data.tp_block_nr = htons(block_nr);
> + tp->x.tp_data.tp_block_nr = htons(block_nr & 0xffff);
>
> saddr.sin_addr = recv_tp->ip.ip_dst;
> saddr.sin_port = recv_tp->udp.uh_dport;
> @@ -255,6 +255,7 @@ static int tftp_send_data(struct tftp_session *spt,
> tftp_session_terminate(spt);
> }
>
> + spt->block_nr = block_nr;
That's not really a nice interface: You pass in tftp_session::block_nr
as argument but you also manipulate it here. I would vote for some pure
variant: either implement a
void tftp_send_next_block(struct tftp_session *spt,
struct tftp_t *recv_tp)
, initializing tftp_session::block_nr to 0 before first call and
incrementing it inside on success. Or do the maintenance of block_nr
completely outside. I leaning a bit to variant 1.
> return 0;
> }
>
> @@ -387,7 +388,7 @@ static void tftp_handle_ack(Slirp *slirp, struct tftp_t
> *tp, int pktlen)
> }
>
> if (tftp_send_data(&slirp->tftp_sessions[s],
> - ntohs(tp->x.tp_data.tp_block_nr) + 1,
> + slirp->tftp_sessions[s].block_nr + 1,
> tp) < 0) {
> return;
> }
> diff --git a/slirp/tftp.h b/slirp/tftp.h
> index 9c364ea..51704e4 100644
> --- a/slirp/tftp.h
> +++ b/slirp/tftp.h
> @@ -37,6 +37,7 @@ struct tftp_session {
>
> struct in_addr client_ip;
> uint16_t client_port;
> + uint32_t block_nr;
>
> int timestamp;
> };
>
Jan
--
Siemens AG, Corporate Technology, CT RTC ITP SDP-DE
Corporate Competence Center Embedded Linux
