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

[Petr Vorel]

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()).

Signed-off-by: Petr Vorel <pvorel@suse.cz>
---
 testcases/lib/tst_net.sh | 66 +++++++++++++++++++++++++++++++++-------
 1 file changed, 55 insertions(+), 11 deletions(-)

diff --git a/testcases/lib/tst_net.sh b/testcases/lib/tst_net.sh
index 4dc0fca926..df16e12a26 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 $?
+}
+
+tst_net_require_ipv6()
+{
+	local err="IPv6 not supported on:"
+	local missing
+
+	tst_net_detect_ipv6 || missing=" lhost"
+	tst_net_detect_ipv6 rhost || missing="$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 $?
+		if tst_net_detect_ipv6; then
+			sysctl -qw net.ipv6.conf.$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 $?
+	if tst_net_detect_ipv6 rhost; then
+		tst_rhost_run -c "sysctl -qw net.ipv6.conf.$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_detect_ipv6; then
+		TST_IPV6=6 tst_add_ipaddr $type $link_num || ret=$?
+	fi
 	TST_IPV6=$backup_tst_ipv6
 
 	return $ret
@@ -971,8 +1003,10 @@ IPV6_RHOST="${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 $?")
+	if tst_net_detect_ipv6; then
+		eval $(tst_net_ip_prefix $IPV6_LHOST || echo "exit $?")
+		eval $(tst_net_ip_prefix -r $IPV6_RHOST || echo "exit $?")
+	fi
 fi
 
 [ -n "$TST_USE_NETNS" -a "$TST_INIT_NETNS" != "no" ] && init_ltp_netspace
@@ -981,19 +1015,29 @@ 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_detect_ipv6; then
+		eval $(tst_net_iface_prefix $IPV6_LHOST || echo "exit $?")
+	fi
+
+	if tst_net_detect_ipv6 rhost; 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_detect_ipv6; 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
 
-- 
2.34.1