Merge pull request #14983 from ssahani/dhcp-use-routes-14982

network: Allow to configure GW even if UseRoutes=false

3 files changed, 55 insertions, 32 deletions

diff --git a/src/network/networkd-dhcp4.c b/src/network/networkd-dhcp4.c
index 5f5a21a59f..34770f6f2b 100644
--- a/src/network/networkd-dhcp4.c
+++ b/src/network/networkd-dhcp4.c
@@ -240,9 +240,6 @@ static int link_set_dhcp_routes(Link *link) {
         if (!link->network) /* link went down while we configured the IP addresses? */
                 return 0;
 
-        if (!link->network->dhcp_use_routes)
-                return 0;
-
         if (!link_has_carrier(link) && !link->network->configure_without_carrier)
                 /* During configuring addresses, the link lost its carrier. As networkd is dropping
                  * the addresses now, let's not configure the routes either. */
@@ -290,37 +287,39 @@ static int link_set_dhcp_routes(Link *link) {
                 }
         }
 
-        for (i = 0; i < n; i++) {
-                _cleanup_(route_freep) Route *route = NULL;
-
-                /* if the DHCP server returns both a Classless Static Routes option and a Static Routes option,
-                   the DHCP client MUST ignore the Static Routes option. */
-                if (classless_route &&
-                    sd_dhcp_route_get_option(static_routes[i]) != SD_DHCP_OPTION_CLASSLESS_STATIC_ROUTE)
-                        continue;
-
-                r = route_new(&route);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not allocate route: %m");
-
-                route->family = AF_INET;
-                route->protocol = RTPROT_DHCP;
-                assert_se(sd_dhcp_route_get_gateway(static_routes[i], &route->gw.in) >= 0);
-                assert_se(sd_dhcp_route_get_destination(static_routes[i], &route->dst.in) >= 0);
-                assert_se(sd_dhcp_route_get_destination_prefix_length(static_routes[i], &route->dst_prefixlen) >= 0);
-                route->priority = link->network->dhcp_route_metric;
-                route->table = table;
-                route->mtu = link->network->dhcp_route_mtu;
-                route->scope = route_scope_from_address(route, &address);
-                if (IN_SET(route->scope, RT_SCOPE_LINK, RT_SCOPE_UNIVERSE))
-                        route->prefsrc.in = address;
+        if (link->network->dhcp_use_routes) {
+                for (i = 0; i < n; i++) {
+                        _cleanup_(route_freep) Route *route = NULL;
 
-                if (set_contains(link->dhcp_routes, route))
-                        continue;
+                        /* if the DHCP server returns both a Classless Static Routes option and a Static Routes option,
+                           the DHCP client MUST ignore the Static Routes option. */
+                        if (classless_route &&
+                            sd_dhcp_route_get_option(static_routes[i]) != SD_DHCP_OPTION_CLASSLESS_STATIC_ROUTE)
+                                continue;
 
-                r = dhcp_route_configure(&route, link);
-                if (r < 0)
-                        return log_link_error_errno(link, r, "Could not set route: %m");
+                        r = route_new(&route);
+                        if (r < 0)
+                                return log_link_error_errno(link, r, "Could not allocate route: %m");
+
+                        route->family = AF_INET;
+                        route->protocol = RTPROT_DHCP;
+                        assert_se(sd_dhcp_route_get_gateway(static_routes[i], &route->gw.in) >= 0);
+                        assert_se(sd_dhcp_route_get_destination(static_routes[i], &route->dst.in) >= 0);
+                        assert_se(sd_dhcp_route_get_destination_prefix_length(static_routes[i], &route->dst_prefixlen) >= 0);
+                        route->priority = link->network->dhcp_route_metric;
+                        route->table = table;
+                        route->mtu = link->network->dhcp_route_mtu;
+                        route->scope = route_scope_from_address(route, &address);
+                        if (IN_SET(route->scope, RT_SCOPE_LINK, RT_SCOPE_UNIVERSE))
+                                route->prefsrc.in = address;
+
+                        if (set_contains(link->dhcp_routes, route))
+                                continue;
+
+                        r = dhcp_route_configure(&route, link);
+                        if (r < 0)
+                                return log_link_error_errno(link, r, "Could not set route: %m");
+                }
         }
 
         r = sd_dhcp_lease_get_router(link->dhcp_lease, &router);
diff --git a/test/test-network/conf/dhcp-client-ipv4-use-routes-no.network b/test/test-network/conf/dhcp-client-ipv4-use-routes-no.network
new file mode 100644
index 0000000000..21e21fabb3
--- /dev/null
+++ b/test/test-network/conf/dhcp-client-ipv4-use-routes-no.network
@@ -0,0 +1,9 @@
+[Match]
+Name=veth99
+
+[Network]
+DHCP=ipv4
+IPv6AcceptRA=false
+
+[DHCPv4]
+UseRoutes=no
diff --git a/test/test-network/systemd-networkd-tests.py b/test/test-network/systemd-networkd-tests.py
index 6cdc96daf7..6cc09235c6 100755
--- a/test/test-network/systemd-networkd-tests.py
+++ b/test/test-network/systemd-networkd-tests.py
@@ -2825,6 +2825,7 @@ class NetworkdDHCPClientTests(unittest.TestCase, Utilities):
         'dhcp-client-ipv4-dhcp-settings.network',
         'dhcp-client-ipv4-only-ipv6-disabled.network',
         'dhcp-client-ipv4-only.network',
+        'dhcp-client-ipv4-use-routes-no.network',
         'dhcp-client-ipv6-only.network',
         'dhcp-client-ipv6-rapid-commit.network',
         'dhcp-client-keep-configuration-dhcp-on-stop.network',
@@ -2929,6 +2930,20 @@ class NetworkdDHCPClientTests(unittest.TestCase, Utilities):
         self.assertRegex(output, r'192.168.5.7 proto dhcp scope link src 192.168.5.181 metric 1024')
         self.assertRegex(output, r'192.168.5.8 proto dhcp scope link src 192.168.5.181 metric 1024')
 
+    def test_dhcp_client_ipv4_use_routes_no(self):
+        copy_unit_to_networkd_unit_path('25-veth.netdev', 'dhcp-server-veth-peer.network', 'dhcp-client-ipv4-use-routes-no.network')
+
+        start_networkd()
+        self.wait_online(['veth-peer:carrier'])
+        start_dnsmasq(additional_options='--dhcp-option=option:dns-server,192.168.5.6,192.168.5.7', lease_time='2m')
+        self.wait_online(['veth99:routable', 'veth-peer:routable'])
+
+        output = check_output('ip route show dev veth99')
+        print(output)
+        self.assertNotRegex(output, r'192.168.5.5')
+        self.assertRegex(output, r'default via 192.168.5.1 proto dhcp src 192.168.5.181 metric 1024')
+        self.assertRegex(output, r'192.168.5.1 proto dhcp scope link src 192.168.5.181 metric 1024')
+
     def test_dhcp_client_ipv4_ipv6(self):
         copy_unit_to_networkd_unit_path('25-veth.netdev', 'dhcp-server-veth-peer.network', 'dhcp-client-ipv6-only.network',
                                         'dhcp-client-ipv4-only.network')