[LTP] [PATCH 1/2] tst_net.sh: Fix for disabled IPv6

[Alexey Kodanev]

Hi Petr,
On 25.01.2022 01:03, Petr Vorel wrote:
> From: Petr Vorel <pvorel@suse.cz>
> 
> Tests failed in tst_init_iface even IPv4 only test was run.
> Allow to init interfaces at least for IPv4.
> 
> Tests which use TST_IPV6=6 needs to be fixed (unless they use
> just tst_ipaddr_un()).
> 
> Store result into TST_NET_{L,R}HOST_IPV6 in order to cache the result.
> 
> Signed-off-by: Petr Vorel <pvorel@suse.cz>
> ---
> Changes v1->v2:
> * cache variables with $TST_NET_{L,R}HOST_IPV6 (mdoucha)
> NOTE: although I'd prefer to cache the result internally and use
> function for detection, tst_net.sh uses variables for most of the
> things, thus keep it this way.
> 
> Kind regards,
> Petr
> 
>  testcases/lib/tst_net.sh | 72 ++++++++++++++++++++++++++++++++++------
>  1 file changed, 61 insertions(+), 11 deletions(-)
> 
> diff --git a/testcases/lib/tst_net.sh b/testcases/lib/tst_net.sh
> index 4dc0fca92..d1ae3042a 100644
> --- a/testcases/lib/tst_net.sh
> +++ b/testcases/lib/tst_net.sh
> @@ -24,7 +24,9 @@ TST_IPV6_FLAG=${TST_IPV6_FLAG:-}
>  tst_net_parse_args()
>  {
>  	case $1 in
> -	6) TST_IPV6=6 TST_IPVER=6 TST_IPV6_FLAG="-6";;
> +	6)  tst_net_require_ipv6
> +		TST_IPV6=6 TST_IPVER=6 TST_IPV6_FLAG="-6"
> +		;;
>  	*) [ "$TST_PARSE_ARGS_CALLER" ] && $TST_PARSE_ARGS_CALLER "$1" "$2";;
>  	esac
>  }
> @@ -100,6 +102,30 @@ tst_brk_()
>  	[ -z "$TST_USE_LEGACY_API" ] && tst_brk $@ || tst_brkm $@
>  }
>  
> +tst_net_detect_ipv6()
> +{
> +	local type="${1:-lhost}"
> +	local cmd='[ -f /proc/net/if_inet6 ]'
> +
> +	if [ "$type" = "lhost" ]; then
> +		$cmd
> +		return $?
> +	fi
> +
> +	tst_rhost_run -c "$cmd"
> +	return $?
> +}
> +
> +tst_net_require_ipv6()
> +{
> +	local err="IPv6 not supported on:"
> +	local missing
> +
> +	[ "$TST_NET_LHOST_IPV6" = 1 ] || missing=" lhost"
> +	[ "$TST_NET_RHOST_IPV6" = 1 ] || missing="$missing rhost"
> +	[ -z "$missing" ] || tst_brk_ TCONF "$err$missing"
> +}
> +
>  init_ltp_netspace()
>  {
>  	local pid
> @@ -517,7 +543,9 @@ tst_init_iface()
>  		ip link set $iface down || return $?
>  		ip route flush dev $iface || return $?
>  		ip addr flush dev $iface || return $?
> -		sysctl -qw net.ipv6.conf.$iface.accept_dad=0 || return $?
> +		if [ "$TST_NET_LHOST_IPV6" = 1 ]; then
> +			sysctl -qw net.ipv6.conf.$iface.accept_dad=0 || return $?
> +		fi
>  		ip link set $iface up
>  		return $?
>  	fi
> @@ -529,7 +557,9 @@ tst_init_iface()
>  	tst_rhost_run -c "ip link set $iface down" || return $?
>  	tst_rhost_run -c "ip route flush dev $iface" || return $?
>  	tst_rhost_run -c "ip addr flush dev $iface" || return $?
> -	tst_rhost_run -c "sysctl -qw net.ipv6.conf.$iface.accept_dad=0" || return $?
> +	if [ "$TST_NET_RHOST_IPV6" = 1 ]; then
> +		tst_rhost_run -c "sysctl -qw net.ipv6.conf.$iface.accept_dad=0" || return $?
> +	fi
>  	tst_rhost_run -c "ip link set $iface up"
>  }
>  
> @@ -606,7 +636,9 @@ tst_restore_ipaddr()
>  	local ret=0
>  	local backup_tst_ipv6=$TST_IPV6
>  	TST_IPV6= tst_add_ipaddr $type $link_num || ret=$?
> -	TST_IPV6=6 tst_add_ipaddr $type $link_num || ret=$?
> +	if [ "$TST_NET_LHOST_IPV6" = 1 ]; then
> +		TST_IPV6=6 tst_add_ipaddr $type $link_num || ret=$?
> +	fi
>  	TST_IPV6=$backup_tst_ipv6
>  
>  	return $ret
> @@ -971,8 +1003,16 @@ IPV6_RHOST="${IPV6_RHOST:-fd00:1:1:1::1/64}"
>  if [ -z "$_tst_net_parse_variables" ]; then
>  	eval $(tst_net_ip_prefix $IPV4_LHOST || echo "exit $?")
>  	eval $(tst_net_ip_prefix -r $IPV4_RHOST || echo "exit $?")
> -	eval $(tst_net_ip_prefix $IPV6_LHOST || echo "exit $?")
> -	eval $(tst_net_ip_prefix -r $IPV6_RHOST || echo "exit $?")
> +
> +	tst_net_detect_ipv6 && TST_NET_LHOST_IPV6=1
> +	tst_net_detect_ipv6 rhost && TST_NET_RHOST_IPV6=1
> +
> +	if [ "$TST_NET_LHOST_IPV6" = 1 ]; then
> +		eval $(tst_net_ip_prefix $IPV6_LHOST || echo "exit $?")
> +	fi
> +	if [ "$TST_NET_RHOST_IPV6" = 1 ]; then
> +		eval $(tst_net_ip_prefix -r $IPV6_RHOST || echo "exit $?")
> +	fi

Do we really need to keep around and check two variables? If at least
one machine doesn't have IPv6, it's not longer necessary to setup the
other.

>  fi
>  
>  [ -n "$TST_USE_NETNS" -a "$TST_INIT_NETNS" != "no" ] && init_ltp_netspace
> @@ -981,19 +1021,29 @@ if [ -z "$_tst_net_parse_variables" ]; then
>  	eval $(tst_net_iface_prefix $IPV4_LHOST || echo "exit $?")
>  	eval $(tst_rhost_run -c 'tst_net_iface_prefix -r '$IPV4_RHOST \
>  		|| echo "exit $?")
> -	eval $(tst_net_iface_prefix $IPV6_LHOST || echo "exit $?")
> -	eval $(tst_rhost_run -c 'tst_net_iface_prefix -r '$IPV6_RHOST \
> -		|| echo "exit $?")
> +
> +	if [ "$TST_NET_LHOST_IPV6" = 1 ]; then
> +		eval $(tst_net_iface_prefix $IPV6_LHOST || echo "exit $?")
> +	fi
> +
> +	if [ "$TST_NET_RHOST_IPV6" = 1 ]; then
> +		eval $(tst_rhost_run -c 'tst_net_iface_prefix -r '$IPV6_RHOST \
> +			|| echo "exit $?")
> +	fi
>  
>  	eval $(tst_net_vars $IPV4_LHOST/$IPV4_LPREFIX \
>  		$IPV4_RHOST/$IPV4_RPREFIX || echo "exit $?")
> -	eval $(tst_net_vars $IPV6_LHOST/$IPV6_LPREFIX \
> -		$IPV6_RHOST/$IPV6_RPREFIX || echo "exit $?")
> +
> +	if [ "$TST_NET_LHOST_IPV6" = 1 ]; then
> +		eval $(tst_net_vars $IPV6_LHOST/$IPV6_LPREFIX \
> +			$IPV6_RHOST/$IPV6_RPREFIX || echo "exit $?")
> +	fi
>  
>  	tst_res_ TINFO "Network config (local -- remote):"
>  	tst_res_ TINFO "$LHOST_IFACES -- $RHOST_IFACES"
>  	tst_res_ TINFO "$IPV4_LHOST/$IPV4_LPREFIX -- $IPV4_RHOST/$IPV4_RPREFIX"
>  	tst_res_ TINFO "$IPV6_LHOST/$IPV6_LPREFIX -- $IPV6_RHOST/$IPV6_RPREFIX"
> +
>  	export _tst_net_parse_variables="yes"
>  fi
>