iproute: support advmss option

function                                             old     new   delta
iproute_modify                                      1164    1221     +57
str_is_lock                                            -      22     +22
packed_usage                                       31372   31382     +10
do_iproute                                           157     132     -25
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 2/1 up/down: 89/-25)             Total: 64 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

2 files changed, 20 insertions, 13 deletions

diff --git a/networking/ip.c b/networking/ip.c
index 155adcfe4..0d66d5319 100644
--- a/networking/ip.c
+++ b/networking/ip.c
@@ -171,7 +171,7 @@
 //usage:       "        NODE_SPEC := PREFIX"IF_FEATURE_IP_RULE(" [table TABLE_ID]")" [proto RTPROTO] [scope SCOPE] [metric METRIC]\n"
 //usage:       "        INFO_SPEC := NH OPTIONS\n"
 //usage:       "        NH := [via [inet|inet6] ADDRESS] [dev IFACE] [src ADDRESS] [onlink]\n"
-//usage:       "        OPTIONS := [mtu NUM]"
+//usage:       "        OPTIONS := [mtu [lock] NUM] [advmss [lock] NUM]"
 //upstream man ip-route:
 //======================
 //ip route { show | flush } SELECTOR
diff --git a/networking/libiproute/iproute.c b/networking/libiproute/iproute.c
index 62fa6efd3..fa616f8fc 100644
--- a/networking/libiproute/iproute.c
+++ b/networking/libiproute/iproute.c
@@ -322,17 +322,25 @@ static int FAST_FUNC print_route(const struct sockaddr_nl *who UNUSED_PARAM,
         return 0;
 }
 
+static int str_is_lock(const char *str)
+{
+        return strcmp(str, "lock") == 0;
+}
+
 /* Return value becomes exitcode. It's okay to not return at all */
 static int iproute_modify(int cmd, unsigned flags, char **argv)
 {
         /* If you add stuff here, update iproute_full_usage */
         static const char keywords[] ALIGN1 =
-                "src\0""via\0""mtu\0""scope\0""protocol\0"IF_FEATURE_IP_RULE("table\0")
+                "src\0""via\0"
+                "mtu\0""advmss\0"
+                "scope\0""protocol\0"IF_FEATURE_IP_RULE("table\0")
                 "dev\0""oif\0""to\0""metric\0""onlink\0";
         enum {
                 ARG_src,
                 ARG_via,
                 ARG_mtu,
+                ARG_advmss,
                 ARG_scope,
                 ARG_protocol,
 IF_FEATURE_IP_RULE(ARG_table,)
@@ -405,12 +413,21 @@ IF_FEATURE_IP_RULE(ARG_table,)
                 } else if (arg == ARG_mtu) {
                         unsigned mtu;
                         NEXT_ARG();
-                        if (strcmp(*argv, "lock") == 0) {
+                        if (str_is_lock(*argv)) {
                                 mxlock |= (1 << RTAX_MTU);
                                 NEXT_ARG();
                         }
                         mtu = get_unsigned(*argv, "mtu");
                         rta_addattr32(mxrta, sizeof(mxbuf), RTAX_MTU, mtu);
+                } else if (arg == ARG_advmss) {
+                        unsigned mss;
+                        NEXT_ARG();
+                        if (str_is_lock(*argv)) {
+                                mxlock |= (1 << RTAX_ADVMSS);
+                                NEXT_ARG();
+                        }
+                        mss = get_unsigned(*argv, "advmss");
+                        rta_addattr32(mxrta, sizeof(mxbuf), RTAX_ADVMSS, mss);
                 } else if (arg == ARG_scope) {
                         uint32_t scope;
                         NEXT_ARG();
@@ -505,16 +522,6 @@ IF_FEATURE_IP_RULE(ARG_table,)
                         if (get_unsigned(&hoplimit, *argv, 0))
                                 invarg("\"hoplimit\" value is invalid\n", *argv);
                         rta_addattr32(mxrta, sizeof(mxbuf), RTAX_HOPLIMIT, hoplimit);
-                } else if (strcmp(*argv, "advmss") == 0) {
-                        unsigned mss;
-                        NEXT_ARG();
-                        if (strcmp(*argv, "lock") == 0) {
-                                mxlock |= (1<<RTAX_ADVMSS);
-                                NEXT_ARG();
-                        }
-                        if (get_unsigned(&mss, *argv, 0))
-                                invarg("\"mss\" value is invalid\n", *argv);
-                        rta_addattr32(mxrta, sizeof(mxbuf), RTAX_ADVMSS, mss);
                 } else if (matches(*argv, "reordering") == 0) {
                         unsigned reord;
                         NEXT_ARG();