netlink: add basic decoding of NETLINK_ROUTE ndmsg attributes

* rtnl_neigh.c: Include "nlattr.h" and "xlat/rtnl_neigh_attrs.h".
(decode_ndmsg): Call decode_nlattr.
* xlat/rtnl_neigh_attrs.in: New file.

Co-authored-by: Fabien Siron <fabien.siron@epita.fr>

diff --git a/rtnl_neigh.c b/rtnl_neigh.c
index c10fc9797bcc751884bd039498160524c18ec288..2ce237a64d49df717818a091fca83e4160f6e665 100644 (file)
--- a/rtnl_neigh.c
+++ b/rtnl_neigh.c
@@ -29,6 +29,7 @@
 
 #include "defs.h"
 #include "netlink_route.h"
+#include "nlattr.h"
 #include "print_fields.h"
 
 #include "netlink.h"
@@ -40,11 +41,13 @@
 #include "xlat/nda_types.h"
 #include "xlat/neighbor_cache_entry_flags.h"
 #include "xlat/neighbor_cache_entry_states.h"
+#include "xlat/rtnl_neigh_attrs.h"
 
 DECL_NETLINK_ROUTE_DECODER(decode_ndmsg)
 {
        struct ndmsg ndmsg = { .ndm_family = family };
-       const size_t offset = sizeof(ndmsg.ndm_family);
+       size_t offset = sizeof(ndmsg.ndm_family);
+       bool decode_nla = false;
 
        PRINT_FIELD_XVAL("{", ndmsg, ndm_family, addrfams, "AF_???");
 
@@ -62,10 +65,18 @@ DECL_NETLINK_ROUTE_DECODER(decode_ndmsg)
                                          "NTF_???");
                        PRINT_FIELD_XVAL(", ", ndmsg, ndm_type,
                                         nda_types, "NDA_???");
+                       decode_nla = true;
                }
        } else
                tprints("...");
        tprints("}");
+
+       offset = NLMSG_ALIGN(sizeof(ndmsg));
+       if (decode_nla && len > offset) {
+               tprints(", ");
+               decode_nlattr(tcp, addr + offset, len - offset,
+                             rtnl_neigh_attrs, "NDA_???", NULL, 0, NULL);
+       }
 }
 
 DECL_NETLINK_ROUTE_DECODER(decode_rtm_getneigh)

diff --git a/xlat/rtnl_neigh_attrs.in b/xlat/rtnl_neigh_attrs.in
new file mode 100644 (file)
index 0000000..fed013a
--- /dev/null
+++ b/xlat/rtnl_neigh_attrs.in
@@ -0,0 +1,12 @@
+NDA_UNSPEC             0
+NDA_DST                        1
+NDA_LLADDR             2
+NDA_CACHEINFO          3
+NDA_PROBES             4
+NDA_VLAN               5
+NDA_PORT               6
+NDA_VNI                        7
+NDA_IFINDEX            8
+NDA_MASTER             9
+NDA_LINK_NETNSID       10
+NDA_SRC_VNI            11