netlink: add a basic netlink attribute parser of AF_PACKET diag

* linux/packet_diag.h (PACKET_DIAG_*): New enum.
* netlink_sock_diag.c: Include "xlat/packet_diag_attrs.h".
(decode_packet_diag_msg): Use decode_nlattr.
* xlat/packet_diag_attrs.in: New file.

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

diff --git a/linux/packet_diag.h b/linux/packet_diag.h
index 10f48d9c2aecbf3baf56216f9a17b611775cf606..3e8120b77c115fbc13b795cffd1fe08ccfc4a06a 100644 (file)
--- a/linux/packet_diag.h
+++ b/linux/packet_diag.h
@@ -26,4 +26,15 @@ struct packet_diag_msg {
        uint32_t pdiag_cookie[2];
 };
 
+enum {
+       PACKET_DIAG_INFO,
+       PACKET_DIAG_MCLIST,
+       PACKET_DIAG_RX_RING,
+       PACKET_DIAG_TX_RING,
+       PACKET_DIAG_FANOUT,
+       PACKET_DIAG_UID,
+       PACKET_DIAG_MEMINFO,
+       PACKET_DIAG_FILTER,
+};
+
 #endif /* !STRACE_LINUX_PACKET_DIAG_H */

diff --git a/netlink_sock_diag.c b/netlink_sock_diag.c
index 98a3fad2b5ab0e4d1b1569f4148f2b68f6bacc9c..d15df970d23a825fe6fb9fe7806ceb63894f8eab 100644 (file)
--- a/netlink_sock_diag.c
+++ b/netlink_sock_diag.c
@@ -49,6 +49,7 @@
 #include "xlat/netlink_diag_show.h"
 #include "xlat/netlink_states.h"
 
+#include "xlat/packet_diag_attrs.h"
 #include "xlat/packet_diag_show.h"
 
 #ifdef AF_SMC
@@ -271,7 +272,8 @@ decode_packet_diag_msg(struct tcb *const tcp,
                       const kernel_ulong_t len)
 {
        struct packet_diag_msg msg = { .pdiag_family = family };
-       const size_t offset = sizeof(msg.pdiag_family);
+       size_t offset = sizeof(msg.pdiag_family);
+       bool decode_nla = false;
 
        PRINT_FIELD_XVAL("{", msg, pdiag_family, addrfams, "AF_???");
        tprints(", ");
@@ -284,10 +286,18 @@ decode_packet_diag_msg(struct tcb *const tcp,
                        PRINT_FIELD_U(", ", msg, pdiag_num);
                        PRINT_FIELD_U(", ", msg, pdiag_ino);
                        PRINT_FIELD_COOKIE(", ", msg, pdiag_cookie);
+                       decode_nla = true;
                }
        } else
                tprints("...");
        tprints("}");
+
+       offset = NLA_ALIGN(sizeof(msg));
+       if (decode_nla && len > offset) {
+               tprints(", ");
+               decode_nlattr(tcp, addr + offset, len - offset,
+                             packet_diag_attrs, "PACKET_DIAG_???");
+       }
 }
 
 static void

diff --git a/xlat/packet_diag_attrs.in b/xlat/packet_diag_attrs.in
new file mode 100644 (file)
index 0000000..5e33871
--- /dev/null
+++ b/xlat/packet_diag_attrs.in
@@ -0,0 +1,9 @@
+#unconditional
+PACKET_DIAG_INFO
+PACKET_DIAG_MCLIST
+PACKET_DIAG_RX_RING
+PACKET_DIAG_TX_RING
+PACKET_DIAG_FANOUT
+PACKET_DIAG_UID
+PACKET_DIAG_MEMINFO
+PACKET_DIAG_FILTER