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