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 1.5 2024/09/02 16:15:33 christos Exp $"); 19 #endif 20 21 /* \summary: Virtual eXtensible Local Area Network (VXLAN) printer */ 22 23 /* specification: RFC 7348 */ 24 25 #include <config.h> 26 27 #include "netdissect-stdinc.h" 28 29 #define ND_LONGJMP_FROM_TCHECK 30 #include "netdissect.h" 31 #include "extract.h" 32 33 static const struct tok vxlan_flags [] = { 34 { 0x08, "I" }, 35 { 0, NULL } 36 }; 37 #define VXLAN_HDR_LEN 8 38 39 /* 40 * VXLAN header, RFC7348 41 * Virtual eXtensible Local Area Network (VXLAN): A Framework 42 * for Overlaying Virtualized Layer 2 Networks over Layer 3 Networks 43 * 44 * 0 1 2 3 45 * 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 46 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 47 * |R|R|R|R|I|R|R|R| Reserved | 48 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 49 * | VXLAN Network Identifier (VNI) | Reserved | 50 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 51 */ 52 53 void 54 vxlan_print(netdissect_options *ndo, const u_char *bp, u_int len) 55 { 56 uint8_t flags; 57 uint32_t vni; 58 59 ndo->ndo_protocol = "vxlan"; 60 nd_print_protocol_caps(ndo); 61 if (len < VXLAN_HDR_LEN) 62 goto invalid; 63 64 flags = GET_U_1(bp); 65 bp += 1; 66 ND_PRINT(", flags [%s] (0x%02x), ", 67 bittok2str_nosep(vxlan_flags, "invalid", flags), flags); 68 69 /* 1st Reserved */ 70 bp += 3; 71 72 vni = GET_BE_U_3(bp); 73 bp += 3; 74 ND_PRINT("vni %u\n", vni); 75 76 /* 2nd Reserved */ 77 ND_TCHECK_1(bp); 78 bp += 1; 79 80 ether_print(ndo, bp, len - VXLAN_HDR_LEN, ND_BYTES_AVAILABLE_AFTER(bp), NULL, NULL); 81 82 return; 83 84 invalid: 85 nd_print_invalid(ndo); 86 } 87