diff options
| -rw-r--r-- | extensions/libxt_tcpmss.c | 6 | ||||
| -rw-r--r-- | extensions/libxt_tcpmss.man | 2 |
2 files changed, 6 insertions, 2 deletions
diff --git a/extensions/libxt_tcpmss.c b/extensions/libxt_tcpmss.c index c7c59717..bcd357aa 100644 --- a/extensions/libxt_tcpmss.c +++ b/extensions/libxt_tcpmss.c @@ -27,8 +27,12 @@ static void tcpmss_parse(struct xt_option_call *cb) xtables_option_parse(cb); mssinfo->mss_min = cb->val.u16_range[0]; mssinfo->mss_max = mssinfo->mss_min; - if (cb->nvals == 2) + if (cb->nvals == 2) { mssinfo->mss_max = cb->val.u16_range[1]; + if (mssinfo->mss_max < mssinfo->mss_min) + xtables_error(PARAMETER_PROBLEM, + "tcpmss: invalid range given"); + } if (cb->invert) mssinfo->invert = 1; } diff --git a/extensions/libxt_tcpmss.man b/extensions/libxt_tcpmss.man index 8ee715cd..8253c363 100644 --- a/extensions/libxt_tcpmss.man +++ b/extensions/libxt_tcpmss.man @@ -1,4 +1,4 @@ This matches the TCP MSS (maximum segment size) field of the TCP header. You can only use this on TCP SYN or SYN/ACK packets, since the MSS is only negotiated during the TCP handshake at connection startup time. .TP [\fB!\fP] \fB\-\-mss\fP \fIvalue\fP[\fB:\fP\fIvalue\fP] -Match a given TCP MSS value or range. +Match a given TCP MSS value or range. If a range is given, the second \fIvalue\fP must be greater than or equal to the first \fIvalue\fP. |