networkd: Support the ability to set MTU in [Route] sections

Add support to set the route MTU.

Closes #9047

3 files changed, 37 insertions, 0 deletions

diff --git a/src/network/networkd-network-gperf.gperf b/src/network/networkd-network-gperf.gperf
index e3d84a365d..23f57ca2f0 100644
--- a/src/network/networkd-network-gperf.gperf
+++ b/src/network/networkd-network-gperf.gperf
@@ -105,6 +105,7 @@ Route.Metric,                           config_parse_route_priority,
 Route.Scope,                            config_parse_route_scope,                       0,                             0
 Route.PreferredSource,                  config_parse_preferred_src,                     0,                             0
 Route.Table,                            config_parse_route_table,                       0,                             0
+Route.MTUBytes,                         config_parse_route_mtu,                         AF_UNSPEC,                     0
 Route.GatewayOnlink,                    config_parse_gateway_onlink,                    0,                             0
 Route.IPv6Preference,                   config_parse_ipv6_route_preference,             0,                             0
 Route.Protocol,                         config_parse_route_protocol,                    0,                             0
diff --git a/src/network/networkd-route.c b/src/network/networkd-route.c
index 63a6b9c2e0..a5303dafa1 100644
--- a/src/network/networkd-route.c
+++ b/src/network/networkd-route.c
@@ -1177,3 +1177,38 @@ int config_parse_quickack(
 
         return 0;
 }
+
+int config_parse_route_mtu(
+                const char *unit,
+                const char *filename,
+                unsigned line,
+                const char *section,
+                unsigned section_line,
+                const char *lvalue,
+                int ltype,
+                const char *rvalue,
+                void *data,
+                void *userdata) {
+
+        Network *network = userdata;
+        _cleanup_(route_freep) Route *n = NULL;
+        int r;
+
+        assert(filename);
+        assert(section);
+        assert(lvalue);
+        assert(rvalue);
+        assert(data);
+
+        r = route_new_static(network, filename, section_line, &n);
+        if (r < 0)
+                return r;
+
+        r = config_parse_mtu(unit, filename, line, section, section_line, lvalue, ltype, rvalue, &n->mtu, userdata);
+        if (r < 0)
+                return r;
+
+        n = NULL;
+
+        return 0;
+}
diff --git a/src/network/networkd-route.h b/src/network/networkd-route.h
index 138bad7a1a..61a81b4150 100644
--- a/src/network/networkd-route.h
+++ b/src/network/networkd-route.h
@@ -75,3 +75,4 @@ CONFIG_PARSER_PROTOTYPE(config_parse_route_protocol);
 CONFIG_PARSER_PROTOTYPE(config_parse_route_type);
 CONFIG_PARSER_PROTOTYPE(config_parse_tcp_window);
 CONFIG_PARSER_PROTOTYPE(config_parse_quickack);
+CONFIG_PARSER_PROTOTYPE(config_parse_route_mtu);