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