From c34120e855b8e7ddd66541d892b38aad573b89f4 Mon Sep 17 00:00:00 2001 From: Jens Nielsen Date: Mon, 23 Apr 2018 16:04:11 +0200 Subject: [PATCH] TFTP server handle retransmit Data packets Signed-off-by: goldsimon --- src/apps/tftp/tftp_server.c | 29 +++++++++++++++++++---------- 1 file changed, 19 insertions(+), 10 deletions(-) diff --git a/src/apps/tftp/tftp_server.c b/src/apps/tftp/tftp_server.c index 07f6170e..57018bd5 100644 --- a/src/apps/tftp/tftp_server.c +++ b/src/apps/tftp/tftp_server.c @@ -294,18 +294,27 @@ recv(void *arg, struct udp_pcb *upcb, struct pbuf *p, const ip_addr_t *addr, u16 } blknum = lwip_ntohs(sbuf[1]); - pbuf_remove_header(p, TFTP_HEADER_LENGTH); + if (blknum == tftp_state.blknum) { + pbuf_remove_header(p, TFTP_HEADER_LENGTH); - ret = tftp_state.ctx->write(tftp_state.handle, p); - if (ret < 0) { - send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "error writing file"); - close_handle(); - } else { + ret = tftp_state.ctx->write(tftp_state.handle, p); + if (ret < 0) { + send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "error writing file"); + close_handle(); + } else { + send_ack(blknum); + } + + if (p->tot_len < TFTP_MAX_PAYLOAD_SIZE) { + close_handle(); + } else { + tftp_state.blknum++; + } + } else if ((u16_t)(blknum + 1) == tftp_state.blknum) { + /* retransmit of previous block, ack again (casting to u16_t to care for overflow) */ send_ack(blknum); - } - - if (p->tot_len < TFTP_MAX_PAYLOAD_SIZE) { - close_handle(); + } else { + send_error(addr, port, TFTP_ERROR_UNKNOWN_TRFR_ID, "Wrong block number"); } break; }