1 /* Copyright (c) 2015, bugyo 2 * All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are met: 6 * 1. Redistributions of source code must retain the above copyright notice, 7 * this list of conditions and the following disclaimer. 8 * 2. Redistributions in binary form must reproduce the above copyright notice, 9 * this list of conditions and the following disclaimer in the documentation 10 * and/or other materials provided with the distribution. 11 * 12 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND 13 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 14 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 15 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR 16 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 17 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 18 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 19 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 20 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 21 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 22 */ 23 24 /* \summary: Generic Protocol Extension for VXLAN (VXLAN GPE) printer */ 25 26 /* specification: draft-ietf-nvo3-vxlan-gpe-10 */ 27 28 #ifdef HAVE_CONFIG_H 29 #include <config.h> 30 #endif 31 32 #include "netdissect-stdinc.h" 33 34 #define ND_LONGJMP_FROM_TCHECK 35 #include "netdissect.h" 36 #include "extract.h" 37 38 static const struct tok vxlan_gpe_flags [] = { 39 { 0x08, "I" }, 40 { 0x04, "P" }, 41 { 0x02, "B" }, 42 { 0x01, "O" }, 43 { 0, NULL } 44 }; 45 46 #define VXLAN_GPE_HDR_LEN 8 47 48 /* 49 * VXLAN GPE header, draft-ietf-nvo3-vxlan-gpe-01 50 * Generic Protocol Extension for VXLAN 51 * 52 * 0 1 2 3 53 * 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 54 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 55 * |R|R|Ver|I|P|R|O| Reserved |Next Protocol | 56 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 57 * | VXLAN Network Identifier (VNI) | Reserved | 58 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 59 */ 60 61 void 62 vxlan_gpe_print(netdissect_options *ndo, const u_char *bp, u_int len) 63 { 64 uint8_t flags; 65 uint8_t next_protocol; 66 uint32_t vni; 67 68 ndo->ndo_protocol = "vxlan_gpe"; 69 ND_PRINT("VXLAN-GPE, "); 70 if (len < VXLAN_GPE_HDR_LEN) { 71 ND_PRINT(" (len %u < %u)", len, VXLAN_GPE_HDR_LEN); 72 goto invalid; 73 } 74 75 flags = GET_U_1(bp); 76 bp += 1; 77 len -= 1; 78 ND_PRINT("flags [%s], ", 79 bittok2str_nosep(vxlan_gpe_flags, "none", flags)); 80 81 /* Reserved */ 82 bp += 2; 83 len -= 2; 84 85 next_protocol = GET_U_1(bp); 86 bp += 1; 87 len -= 1; 88 89 vni = GET_BE_U_3(bp); 90 bp += 3; 91 len -= 3; 92 93 /* Reserved */ 94 ND_TCHECK_1(bp); 95 bp += 1; 96 len -= 1; 97 98 ND_PRINT("vni %u", vni); 99 ND_PRINT(ndo->ndo_vflag ? "\n " : ": "); 100 101 switch (next_protocol) { 102 case 0x1: 103 ip_print(ndo, bp, len); 104 break; 105 case 0x2: 106 ip6_print(ndo, bp, len); 107 break; 108 case 0x3: 109 ether_print(ndo, bp, len, ND_BYTES_AVAILABLE_AFTER(bp), NULL, NULL); 110 break; 111 case 0x4: 112 nsh_print(ndo, bp, len); 113 break; 114 default: 115 ND_PRINT("ERROR: unknown-next-protocol"); 116 goto invalid; 117 } 118 119 return; 120 121 invalid: 122 nd_print_invalid(ndo); 123 } 124 125