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 #include <sys/cdefs.h> 17 #ifndef lint 18 __RCSID("$NetBSD: print-vxlan.c,v 1.4 2023/08/17 20:19:40 christos Exp $"); 19 #endif 20 21 /* \summary: Virtual eXtensible Local Area Network (VXLAN) printer */ 22 23 /* specification: RFC 7348 */ 24 25 #ifdef HAVE_CONFIG_H 26 #include <config.h> 27 #endif 28 29 #include "netdissect-stdinc.h" 30 31 #define ND_LONGJMP_FROM_TCHECK 32 #include "netdissect.h" 33 #include "extract.h" 34 35 static const struct tok vxlan_flags [] = { 36 { 0x08, "I" }, 37 { 0, NULL } 38 }; 39 #define VXLAN_HDR_LEN 8 40 41 /* 42 * VXLAN header, RFC7348 43 * Virtual eXtensible Local Area Network (VXLAN): A Framework 44 * for Overlaying Virtualized Layer 2 Networks over Layer 3 Networks 45 * 46 * 0 1 2 3 47 * 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 48 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 49 * |R|R|R|R|I|R|R|R| Reserved | 50 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 51 * | VXLAN Network Identifier (VNI) | Reserved | 52 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 53 */ 54 55 void 56 vxlan_print(netdissect_options *ndo, const u_char *bp, u_int len) 57 { 58 uint8_t flags; 59 uint32_t vni; 60 61 ndo->ndo_protocol = "vxlan"; 62 nd_print_protocol_caps(ndo); 63 if (len < VXLAN_HDR_LEN) 64 goto invalid; 65 66 flags = GET_U_1(bp); 67 bp += 1; 68 ND_PRINT(", flags [%s] (0x%02x), ", 69 bittok2str_nosep(vxlan_flags, "invalid", flags), flags); 70 71 /* 1st Reserved */ 72 bp += 3; 73 74 vni = GET_BE_U_3(bp); 75 bp += 3; 76 ND_PRINT("vni %u\n", vni); 77 78 /* 2nd Reserved */ 79 ND_TCHECK_1(bp); 80 bp += 1; 81 82 ether_print(ndo, bp, len - VXLAN_HDR_LEN, ND_BYTES_AVAILABLE_AFTER(bp), NULL, NULL); 83 84 return; 85 86 invalid: 87 nd_print_invalid(ndo); 88 } 89