aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorFlorin Coras <fcoras@cisco.com>2020-12-18 13:30:45 -0800
committerFlorin Coras <florin.coras@gmail.com>2020-12-21 15:16:57 +0000
commitf9e500e81698bbe7f78f65792e934ad6a16fa602 (patch)
tree357b837bbe95385b17938eb05ecfde02a9aa0b72
parent40a5da8e96a910287001e9db119d1f0134fc9fb8 (diff)
tcp: terminate options with nops
On the one hand, make sure options are terminated with NOPs to avoid issues with clients that can't parse options that don't end on an u32 boundary. On the other, make sure the padding is rfc compliant. If options end with EOL the padding should be zeros. The current change does not use EOL so the padding is NOPs. Type: improvement Signed-off-by: Florin Coras <fcoras@cisco.com> Change-Id: I608056707ef9658ca90b9c095e84a0689d8000d7
-rw-r--r--src/vnet/tcp/tcp_packet.h12
1 files changed, 4 insertions, 8 deletions
diff --git a/src/vnet/tcp/tcp_packet.h b/src/vnet/tcp/tcp_packet.h
index 9ccd8e0ceb3..f9c6db4f8c4 100644
--- a/src/vnet/tcp/tcp_packet.h
+++ b/src/vnet/tcp/tcp_packet.h
@@ -370,14 +370,10 @@ tcp_options_write (u8 * data, tcp_options_t * opts)
}
}
- /* Terminate TCP options */
- if (opts_len % 4)
- {
- *data++ = TCP_OPTION_EOL;
- opts_len += TCP_OPTION_LEN_EOL;
- }
-
- /* Pad with zeroes to a u32 boundary */
+ /* Terminate TCP options by padding with NOPs to a u32 boundary. Avoid using
+ * EOL because, it seems, it can break peers with broken option parsers that
+ * rely on options ending on a u32 boundary.
+ */
while (opts_len % 4)
{
*data++ = TCP_OPTION_NOOP;