X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/949a22064d3534eddeb8aa2b9c36a50e45fe16fa..HEAD:/print-vxlan.c

diff --git a/print-vxlan.c b/print-vxlan.c
index 80344634..44fe3367 100644
--- a/print-vxlan.c
+++ b/print-vxlan.c
@@ -13,23 +13,30 @@
  * Original code by Francesco Fondelli (francesco dot fondelli, gmail dot com)
  */
 
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif
+/* \summary: Virtual eXtensible Local Area Network (VXLAN) printer */
 
-#include <tcpdump-stdinc.h>
+/* specification: RFC 7348 */
 
-#include <stdio.h>
-#include <stdlib.h>
+#include <config.h>
 
-#include "interface.h"
+#include "netdissect-stdinc.h"
+
+#define ND_LONGJMP_FROM_TCHECK
+#include "netdissect.h"
 #include "extract.h"
-#include "addrtoname.h"
 
-#include "udp.h"
+#define VXLAN_I     0x08 /* Instance Bit */
+
+static const struct tok vxlan_flags [] = {
+    { VXLAN_I, "I" },
+    { 0, NULL }
+};
+#define VXLAN_HDR_LEN 8
 
 /*
- * VXLAN header, draft-mahalingam-dutt-dcops-vxlan-03
+ * VXLAN header, RFC7348
+ *               Virtual eXtensible Local Area Network (VXLAN): A Framework
+ *               for Overlaying Virtualized Layer 2 Networks over Layer 3 Networks
  *
  *     0                   1                   2                   3
  *     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
@@ -37,38 +44,44 @@
  *    |R|R|R|R|I|R|R|R|            Reserved                           |
  *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  *    |                VXLAN Network Identifier (VNI) |   Reserved    |
- *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
+ *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  */
 
 void
-vxlan_print(const u_char *bp, u_int len)
+vxlan_print(netdissect_options *ndo, const u_char *bp, u_int len)
 {
-    u_int8_t flags;
-    u_int32_t vni;
-    
-    if (len < 8) {
-        printf("[|VXLAN]");
-        return;
-    }
+    uint8_t flags;
 
-    flags = *bp;
-    bp += 4;
+    ndo->ndo_protocol = "vxlan";
+    nd_print_protocol_caps(ndo);
+    if (len < VXLAN_HDR_LEN)
+        goto invalid;
 
-    vni = EXTRACT_24BITS(bp);
-    bp += 4;
+    flags = GET_U_1(bp);
+    bp += 1;
+    ND_PRINT(", flags [%s] (0x%02x), ",
+             bittok2str_nosep(vxlan_flags, "invalid", flags), flags);
 
-    printf("VXLAN, ");
+    /* 1st Reserved */
+    bp += 3;
 
-    fputs("flags [", stdout);
-    if (flags & 0x08)
-        fputs("I", stdout);
+    /*
+     * RFC 7348 says that the I flag MUST be set.
+     */
+    if (flags & VXLAN_I)
+        ND_PRINT("vni %u\n", GET_BE_U_3(bp));
     else
-        fputs(".", stdout);
-    fputs("] ", stdout);
+        ND_PRINT("ERROR: I flag not set\n");
+    bp += 3;
 
-    printf("(0x%02x), ", flags);
-    printf("vni %u\n", vni);
+    /* 2nd Reserved */
+    ND_TCHECK_1(bp);
+    bp += 1;
+
+    ether_print(ndo, bp, len - VXLAN_HDR_LEN, ND_BYTES_AVAILABLE_AFTER(bp), NULL, NULL);
 
-    ether_print(gndo, bp, len - 8, len - 8, NULL, NULL);
     return;
+
+invalid:
+    nd_print_invalid(ndo);
 }