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 #include <sys/cdefs.h>
25 #ifndef lint
26 __RCSID("$NetBSD: print-vxlan-gpe.c,v 1.5 2024/09/02 16:15:33 christos Exp $");
27 #endif
28
29 /* \summary: Generic Protocol Extension for VXLAN (VXLAN GPE) printer */
30
31 /* specification: draft-ietf-nvo3-vxlan-gpe-10 */
32
33 #include <config.h>
34
35 #include "netdissect-stdinc.h"
36
37 #define ND_LONGJMP_FROM_TCHECK
38 #include "netdissect.h"
39 #include "extract.h"
40
41 static const struct tok vxlan_gpe_flags [] = {
42 { 0x08, "I" },
43 { 0x04, "P" },
44 { 0x02, "B" },
45 { 0x01, "O" },
46 { 0, NULL }
47 };
48
49 #define VXLAN_GPE_HDR_LEN 8
50
51 /*
52 * VXLAN GPE header, draft-ietf-nvo3-vxlan-gpe-01
53 * Generic Protocol Extension for VXLAN
54 *
55 * 0 1 2 3
56 * 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
57 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
58 * |R|R|Ver|I|P|R|O| Reserved |Next Protocol |
59 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
60 * | VXLAN Network Identifier (VNI) | Reserved |
61 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
62 */
63
64 void
vxlan_gpe_print(netdissect_options * ndo,const u_char * bp,u_int len)65 vxlan_gpe_print(netdissect_options *ndo, const u_char *bp, u_int len)
66 {
67 uint8_t flags;
68 uint8_t next_protocol;
69 uint32_t vni;
70
71 ndo->ndo_protocol = "vxlan_gpe";
72 ND_PRINT("VXLAN-GPE, ");
73 if (len < VXLAN_GPE_HDR_LEN) {
74 ND_PRINT(" (len %u < %u)", len, VXLAN_GPE_HDR_LEN);
75 goto invalid;
76 }
77
78 flags = GET_U_1(bp);
79 bp += 1;
80 len -= 1;
81 ND_PRINT("flags [%s], ",
82 bittok2str_nosep(vxlan_gpe_flags, "none", flags));
83
84 /* Reserved */
85 bp += 2;
86 len -= 2;
87
88 next_protocol = GET_U_1(bp);
89 bp += 1;
90 len -= 1;
91
92 vni = GET_BE_U_3(bp);
93 bp += 3;
94 len -= 3;
95
96 /* Reserved */
97 ND_TCHECK_1(bp);
98 bp += 1;
99 len -= 1;
100
101 ND_PRINT("vni %u", vni);
102 ND_PRINT(ndo->ndo_vflag ? "\n " : ": ");
103
104 switch (next_protocol) {
105 case 0x1:
106 ip_print(ndo, bp, len);
107 break;
108 case 0x2:
109 ip6_print(ndo, bp, len);
110 break;
111 case 0x3:
112 ether_print(ndo, bp, len, ND_BYTES_AVAILABLE_AFTER(bp), NULL, NULL);
113 break;
114 case 0x4:
115 nsh_print(ndo, bp, len);
116 break;
117 default:
118 ND_PRINT("ERROR: unknown-next-protocol");
119 goto invalid;
120 }
121
122 return;
123
124 invalid:
125 nd_print_invalid(ndo);
126 }
127
128