[nft] doc: update ct timeout section with the state names

docs are too terse and did not have the list of valid timeout states.
While at it, adjust default stream timeout of udp to 120, this is the
current kernel default.

Signed-off-by: Florian Westphal <fw@strlen.de>
---
 doc/stateful-objects.txt | 11 +++++++++++
 src/rule.c               |  2 +-
 2 files changed, 12 insertions(+), 1 deletion(-)

On Thu, Oct 28, 2021 at 05:37:24PM +0200, Florian Westphal wrote:
> docs are too terse and did not have the list of valid timeout states.
> While at it, adjust default stream timeout of udp to 120, this is the
> current kernel default.

ack.

> Signed-off-by: Florian Westphal <fw@strlen.de>
> ---
>  doc/stateful-objects.txt | 11 +++++++++++
>  src/rule.c               |  2 +-
>  2 files changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/doc/stateful-objects.txt b/doc/stateful-objects.txt
> index 4972969eb250..e3c79220811f 100644
> --- a/doc/stateful-objects.txt
> +++ b/doc/stateful-objects.txt
> @@ -77,6 +77,17 @@ per ct timeout comment field |
>  string
>  |=================
>  
> +tcp connection state names that can have a specific timeout value are:
> +
> +'close', 'close_wait', 'established', 'fin_wait', 'last_ack', 'retrans', 'syn_recv', 'syn_sent', 'time_wait' and 'unack'.
> +
> +You can use 'sysctl -a |grep net.netfilter.nf_conntrack_tcp_timeout_' to view and change the system-wide defaults.
> +'ct timeout' allows for flow-specific settings, without changing the global timeouts.
> +
> +For example, tcp port 53 could have much lower settings than other traffic.
> +
> +udp state names that can have a specific timeout value are 'replied' and 'unreplied'.
> +
>  .defining and assigning ct timeout policy
>  ----------------------------------
>  table ip filter {
> diff --git a/src/rule.c b/src/rule.c
> index c7bc6bcf3496..b1700c40079d 100644
> --- a/src/rule.c
> +++ b/src/rule.c
> @@ -72,7 +72,7 @@ static uint32_t tcp_dflt_timeout[] = {
>  
>  static uint32_t udp_dflt_timeout[] = {
>  	[NFTNL_CTTIMEOUT_UDP_UNREPLIED]		= 30,
> -	[NFTNL_CTTIMEOUT_UDP_REPLIED]		= 180,
> +	[NFTNL_CTTIMEOUT_UDP_REPLIED]		= 120,
>  };
>  
>  struct timeout_protocol timeout_protocol[IPPROTO_MAX] = {
> -- 
> 2.32.0
>