1 /*
2 * Copyright (c) 2014 VMware, Inc. All Rights Reserved.
3 *
4 * Jesse Gross <jesse@nicira.com>
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that: (1) source code
8 * distributions retain the above copyright notice and this paragraph
9 * in its entirety, and (2) distributions including binary code include
10 * the above copyright notice and this paragraph in its entirety in
11 * the documentation or other materials provided with the distribution.
12 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND
13 * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
14 * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
15 * FOR A PARTICULAR PURPOSE.
16 */
17
18 /* \summary: Generic Network Virtualization Encapsulation (Geneve) printer */
19
20 #ifdef HAVE_CONFIG_H
21 #include "config.h"
22 #endif
23
24 #include <netdissect-stdinc.h>
25
26 #include "netdissect.h"
27 #include "extract.h"
28 #include "ethertype.h"
29
30 /*
31 * Geneve header, draft-ietf-nvo3-geneve
32 *
33 * 0 1 2 3
34 * 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
35 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
36 * |Ver| Opt Len |O|C| Rsvd. | Protocol Type |
37 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
38 * | Virtual Network Identifier (VNI) | Reserved |
39 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
40 * | Variable Length Options |
41 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
42 *
43 * Options:
44 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
45 * | Option Class | Type |R|R|R| Length |
46 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
47 * | Variable Option Data |
48 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
49 */
50
51 #define VER_SHIFT 6
52 #define HDR_OPTS_LEN_MASK 0x3F
53
54 #define FLAG_OAM (1 << 7)
55 #define FLAG_CRITICAL (1 << 6)
56 #define FLAG_R1 (1 << 5)
57 #define FLAG_R2 (1 << 4)
58 #define FLAG_R3 (1 << 3)
59 #define FLAG_R4 (1 << 2)
60 #define FLAG_R5 (1 << 1)
61 #define FLAG_R6 (1 << 0)
62
63 #define OPT_TYPE_CRITICAL (1 << 7)
64 #define OPT_LEN_MASK 0x1F
65
66 static const struct tok geneve_flag_values[] = {
67 { FLAG_OAM, "O" },
68 { FLAG_CRITICAL, "C" },
69 { FLAG_R1, "R1" },
70 { FLAG_R2, "R2" },
71 { FLAG_R3, "R3" },
72 { FLAG_R4, "R4" },
73 { FLAG_R5, "R5" },
74 { FLAG_R6, "R6" },
75 { 0, NULL }
76 };
77
78 static const char *
format_opt_class(uint16_t opt_class)79 format_opt_class(uint16_t opt_class)
80 {
81 switch (opt_class) {
82 case 0x0100:
83 return "Linux";
84 case 0x0101:
85 return "Open vSwitch";
86 case 0x0102:
87 return "Open Virtual Networking (OVN)";
88 case 0x0103:
89 return "In-band Network Telemetry (INT)";
90 case 0x0104:
91 return "VMware";
92 default:
93 if (opt_class <= 0x00ff)
94 return "Standard";
95 else if (opt_class >= 0xfff0)
96 return "Experimental";
97 }
98
99 return "Unknown";
100 }
101
102 static void
geneve_opts_print(netdissect_options * ndo,const u_char * bp,u_int len)103 geneve_opts_print(netdissect_options *ndo, const u_char *bp, u_int len)
104 {
105 const char *sep = "";
106
107 while (len > 0) {
108 uint16_t opt_class;
109 uint8_t opt_type;
110 uint8_t opt_len;
111
112 ND_PRINT((ndo, "%s", sep));
113 sep = ", ";
114
115 opt_class = EXTRACT_16BITS(bp);
116 opt_type = *(bp + 2);
117 opt_len = 4 + ((*(bp + 3) & OPT_LEN_MASK) * 4);
118
119 ND_PRINT((ndo, "class %s (0x%x) type 0x%x%s len %u",
120 format_opt_class(opt_class), opt_class, opt_type,
121 opt_type & OPT_TYPE_CRITICAL ? "(C)" : "", opt_len));
122
123 if (opt_len > len) {
124 ND_PRINT((ndo, " [bad length]"));
125 return;
126 }
127
128 if (ndo->ndo_vflag > 1 && opt_len > 4) {
129 const uint32_t *data = (const uint32_t *)(bp + 4);
130 int i;
131
132 ND_PRINT((ndo, " data"));
133
134 for (i = 4; i < opt_len; i += 4) {
135 ND_PRINT((ndo, " %08x", EXTRACT_32BITS(data)));
136 data++;
137 }
138 }
139
140 bp += opt_len;
141 len -= opt_len;
142 }
143 }
144
145 void
geneve_print(netdissect_options * ndo,const u_char * bp,u_int len)146 geneve_print(netdissect_options *ndo, const u_char *bp, u_int len)
147 {
148 uint8_t ver_opt;
149 u_int version;
150 uint8_t flags;
151 uint16_t prot;
152 uint32_t vni;
153 uint8_t reserved;
154 u_int opts_len;
155
156 ND_PRINT((ndo, "Geneve"));
157
158 ND_TCHECK2(*bp, 8);
159
160 ver_opt = *bp;
161 bp += 1;
162 len -= 1;
163
164 version = ver_opt >> VER_SHIFT;
165 if (version != 0) {
166 ND_PRINT((ndo, " ERROR: unknown-version %u", version));
167 return;
168 }
169
170 flags = *bp;
171 bp += 1;
172 len -= 1;
173
174 prot = EXTRACT_16BITS(bp);
175 bp += 2;
176 len -= 2;
177
178 vni = EXTRACT_24BITS(bp);
179 bp += 3;
180 len -= 3;
181
182 reserved = *bp;
183 bp += 1;
184 len -= 1;
185
186 ND_PRINT((ndo, ", Flags [%s]",
187 bittok2str_nosep(geneve_flag_values, "none", flags)));
188 ND_PRINT((ndo, ", vni 0x%x", vni));
189
190 if (reserved)
191 ND_PRINT((ndo, ", rsvd 0x%x", reserved));
192
193 if (ndo->ndo_eflag)
194 ND_PRINT((ndo, ", proto %s (0x%04x)",
195 tok2str(ethertype_values, "unknown", prot), prot));
196
197 opts_len = (ver_opt & HDR_OPTS_LEN_MASK) * 4;
198
199 if (len < opts_len) {
200 ND_PRINT((ndo, " truncated-geneve - %u bytes missing",
201 opts_len - len));
202 return;
203 }
204
205 ND_TCHECK2(*bp, opts_len);
206
207 if (opts_len > 0) {
208 ND_PRINT((ndo, ", options ["));
209
210 if (ndo->ndo_vflag)
211 geneve_opts_print(ndo, bp, opts_len);
212 else
213 ND_PRINT((ndo, "%u bytes", opts_len));
214
215 ND_PRINT((ndo, "]"));
216 }
217
218 bp += opts_len;
219 len -= opts_len;
220
221 if (ndo->ndo_vflag < 1)
222 ND_PRINT((ndo, ": "));
223 else
224 ND_PRINT((ndo, "\n\t"));
225
226 if (ethertype_print(ndo, prot, bp, len, ndo->ndo_snapend - bp, NULL, NULL) == 0) {
227 if (prot == ETHERTYPE_TEB)
228 ether_print(ndo, bp, len, ndo->ndo_snapend - bp, NULL, NULL);
229 else
230 ND_PRINT((ndo, "geneve-proto-0x%x", prot));
231 }
232
233 return;
234
235 trunc:
236 ND_PRINT((ndo, " [|geneve]"));
237 }
238