1 /* 2 * Redistribution and use in source and binary forms, with or without 3 * modification, are permitted provided that: (1) source code 4 * distributions retain the above copyright notice and this paragraph 5 * in its entirety, and (2) distributions including binary code include 6 * the above copyright notice and this paragraph in its entirety in 7 * the documentation or other materials provided with the distribution. 8 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND 9 * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT 10 * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 11 * FOR A PARTICULAR PURPOSE. 12 * 13 * Original code by Francesco Fondelli (francesco dot fondelli, gmail dot com) 14 */ 15 16 /* \summary: Virtual eXtensible Local Area Network (VXLAN) printer */ 17 18 /* specification: RFC 7348 */ 19 20 #ifdef HAVE_CONFIG_H 21 #include "config.h" 22 #endif 23 24 #include <netdissect-stdinc.h> 25 26 #include "netdissect.h" 27 #include "extract.h" 28 29 static const char tstr[] = " [|VXLAN]"; 30 31 #define VXLAN_HDR_LEN 8 32 33 /* 34 * VXLAN header, RFC7348 35 * Virtual eXtensible Local Area Network (VXLAN): A Framework 36 * for Overlaying Virtualized Layer 2 Networks over Layer 3 Networks 37 * 38 * 0 1 2 3 39 * 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 40 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 41 * |R|R|R|R|I|R|R|R| Reserved | 42 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 43 * | VXLAN Network Identifier (VNI) | Reserved | 44 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 45 */ 46 47 void 48 vxlan_print(netdissect_options *ndo, const u_char *bp, u_int len) 49 { 50 uint8_t flags; 51 uint32_t vni; 52 53 if (len < VXLAN_HDR_LEN) 54 goto trunc; 55 56 ND_TCHECK2(*bp, VXLAN_HDR_LEN); 57 58 flags = *bp; 59 bp += 4; 60 61 vni = EXTRACT_24BITS(bp); 62 bp += 4; 63 64 ND_PRINT((ndo, "VXLAN, ")); 65 ND_PRINT((ndo, "flags [%s] (0x%02x), ", flags & 0x08 ? "I" : ".", flags)); 66 ND_PRINT((ndo, "vni %u\n", vni)); 67 68 ether_print(ndo, bp, len - VXLAN_HDR_LEN, ndo->ndo_snapend - bp, NULL, NULL); 69 70 return; 71 72 trunc: 73 ND_PRINT((ndo, "%s", tstr)); 74 } 75