From 38bd7db313319ea40187c2bbc74862e0518aa98d Mon Sep 17 00:00:00 2001 From: Craig Rodrigues Date: Sun, 31 Jul 2011 03:12:20 +0000 Subject: [PATCH] In the old TFTP server, there was an undocumented behavior where the block counter would rollover to 0 if a file larger than 65535 blocks was transferred. With the default block size of 512 octets per block, this is a file size of approximately 32 megabytes. The new TFTP server code would report an error and stop transferring the file if a file was larger than 65535 blocks. This patch restores the old TFTP server's behavior to the new TFTP server code. If a TFTP client transfers a file larger than 65535 blocks, and does *not* specify the "rollover" option, then automatically rollover the block counter to 0 every time we reach 65535 blocks. This restores interoperability with the FreeBSD 6 TFTP client. Without this change, if a FreeBSD 6 TFTP client tried to retrieve a file larger than 65535 blocks from a FreeBSD 9 TFTP server , the transfer would fail. The same file could be retrieved successfully if the same FreeBSD 6 TFTP client was used against a FreeBSD 6 TFTP server. Approved by: re (kib) Tested by: Pawan Gupta , Obtained from: Juniper Networks --- libexec/tftpd/tftp-transfer.c | 28 ++++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) diff --git a/libexec/tftpd/tftp-transfer.c b/libexec/tftpd/tftp-transfer.c index fd0e00d94096..d0c8a95665ab 100644 --- a/libexec/tftpd/tftp-transfer.c +++ b/libexec/tftpd/tftp-transfer.c @@ -129,14 +129,16 @@ tftp_send(int peer, uint16_t *block, struct tftp_stats *ts) (*block)++; if (oldblock > *block) { if (options[OPT_ROLLOVER].o_request == NULL) { - tftp_log(LOG_ERR, - "Block rollover but not allowed."); - send_error(peer, EBADOP); - gettimeofday(&(ts->tstop), NULL); - return; + /* + * "rollover" option not specified in + * tftp client. Default to rolling block + * counter to 0. + */ + *block = 0; + } else { + *block = atoi(options[OPT_ROLLOVER].o_request); } - *block = atoi(options[OPT_ROLLOVER].o_request); ts->rollovers++; } gettimeofday(&(ts->tstop), NULL); @@ -196,14 +198,16 @@ tftp_receive(int peer, uint16_t *block, struct tftp_stats *ts, (*block)++; if (oldblock > *block) { if (options[OPT_ROLLOVER].o_request == NULL) { - tftp_log(LOG_ERR, - "Block rollover but not allowed."); - send_error(peer, EBADOP); - gettimeofday(&(ts->tstop), NULL); - return; + /* + * "rollover" option not specified in + * tftp client. Default to rolling block + * counter to 0. + */ + *block = 0; + } else { + *block = atoi(options[OPT_ROLLOVER].o_request); } - *block = atoi(options[OPT_ROLLOVER].o_request); ts->rollovers++; }