tcpdump  4.99.1
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print-geneve.c
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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 *
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
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("%s", sep);
113  sep = ", ";
114 
115  opt_class = GET_BE_U_2(bp);
116  opt_type = GET_U_1(bp + 2);
117  opt_len = 4 + ((GET_U_1(bp + 3) & OPT_LEN_MASK) * 4);
118 
119  ND_PRINT("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(" [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(" data");
133 
134  for (i = 4; i < opt_len; i += 4) {
135  ND_PRINT(" %08x", GET_BE_U_4(data));
136  data++;
137  }
138  }
139 
140  bp += opt_len;
141  len -= opt_len;
142  }
143 }
144 
145 void
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  ndo->ndo_protocol = "geneve";
157  ND_PRINT("Geneve");
158 
159  if (len < 8) {
160  ND_PRINT(" [length %u < 8]", len);
161  nd_print_invalid(ndo);
162  return;
163  }
164 
165  ND_TCHECK_8(bp);
166 
167  ver_opt = GET_U_1(bp);
168  bp += 1;
169  len -= 1;
170 
171  version = ver_opt >> VER_SHIFT;
172  if (version != 0) {
173  ND_PRINT(" ERROR: unknown-version %u", version);
174  return;
175  }
176 
177  flags = GET_U_1(bp);
178  bp += 1;
179  len -= 1;
180 
181  prot = GET_BE_U_2(bp);
182  bp += 2;
183  len -= 2;
184 
185  vni = GET_BE_U_3(bp);
186  bp += 3;
187  len -= 3;
188 
189  reserved = GET_U_1(bp);
190  bp += 1;
191  len -= 1;
192 
193  ND_PRINT(", Flags [%s]",
194  bittok2str_nosep(geneve_flag_values, "none", flags));
195  ND_PRINT(", vni 0x%x", vni);
196 
197  if (reserved)
198  ND_PRINT(", rsvd 0x%x", reserved);
199 
200  if (ndo->ndo_eflag)
201  ND_PRINT(", proto %s (0x%04x)",
202  tok2str(ethertype_values, "unknown", prot), prot);
203 
204  opts_len = (ver_opt & HDR_OPTS_LEN_MASK) * 4;
205 
206  if (len < opts_len) {
207  ND_PRINT(" truncated-geneve - %u bytes missing",
208  opts_len - len);
209  return;
210  }
211 
212  ND_TCHECK_LEN(bp, opts_len);
213 
214  if (opts_len > 0) {
215  ND_PRINT(", options [");
216 
217  if (ndo->ndo_vflag)
218  geneve_opts_print(ndo, bp, opts_len);
219  else
220  ND_PRINT("%u bytes", opts_len);
221 
222  ND_PRINT("]");
223  }
224 
225  bp += opts_len;
226  len -= opts_len;
227 
228  if (ndo->ndo_vflag < 1)
229  ND_PRINT(": ");
230  else
231  ND_PRINT("\n\t");
232 
233  if (ethertype_print(ndo, prot, bp, len, ND_BYTES_AVAILABLE_AFTER(bp), NULL, NULL) == 0) {
234  if (prot == ETHERTYPE_TEB)
235  ether_print(ndo, bp, len, ND_BYTES_AVAILABLE_AFTER(bp), NULL, NULL);
236  else
237  ND_PRINT("geneve-proto-0x%x", prot);
238  }
239 
240  return;
241 
242 trunc:
243  nd_print_trunc(ndo);
244 }
const struct tok ethertype_values[]
Definition: print-ether.c:52
#define ETHERTYPE_TEB
Definition: ethertype.h:85
#define GET_BE_U_4(p)
Definition: extract.h:877
#define GET_BE_U_3(p)
Definition: extract.h:876
#define GET_BE_U_2(p)
Definition: extract.h:875
#define ND_TCHECK_8(p)
Definition: extract.h:573
#define GET_U_1(p)
Definition: extract.h:872
#define ND_TCHECK_LEN(p, l)
Definition: netdissect.h:368
const char * tok2str(const struct tok *, const char *, u_int)
Definition: util-print.c:485
int ethertype_print(netdissect_options *, u_short, const u_char *, u_int, u_int, const struct lladdr_info *, const struct lladdr_info *)
Definition: print-ether.c:522
void nd_print_invalid(netdissect_options *)
Definition: util-print.c:429
void nd_print_trunc(netdissect_options *)
Definition: util-print.c:409
char * bittok2str_nosep(const struct tok *, const char *, u_int)
Definition: util-print.c:547
u_int ether_print(netdissect_options *, const u_char *, u_int, u_int, void(*)(netdissect_options *, const u_char *), const u_char *)
#define ND_PRINT(...)
Definition: netdissect.h:385
#define ND_BYTES_AVAILABLE_AFTER(p)
Definition: netdissect.h:383
#define OPT_LEN_MASK
Definition: print-geneve.c:64
#define FLAG_R1
Definition: print-geneve.c:56
#define VER_SHIFT
Definition: print-geneve.c:51
#define FLAG_R2
Definition: print-geneve.c:57
static const struct tok geneve_flag_values[]
Definition: print-geneve.c:66
#define HDR_OPTS_LEN_MASK
Definition: print-geneve.c:52
#define FLAG_R3
Definition: print-geneve.c:58
#define FLAG_CRITICAL
Definition: print-geneve.c:55
#define FLAG_R5
Definition: print-geneve.c:60
static void geneve_opts_print(netdissect_options *ndo, const u_char *bp, u_int len)
Definition: print-geneve.c:103
#define OPT_TYPE_CRITICAL
Definition: print-geneve.c:63
static const char * format_opt_class(uint16_t opt_class)
Definition: print-geneve.c:79
#define FLAG_OAM
Definition: print-geneve.c:54
void geneve_print(netdissect_options *ndo, const u_char *bp, u_int len)
Definition: print-geneve.c:146
#define FLAG_R4
Definition: print-geneve.c:59
#define FLAG_R6
Definition: print-geneve.c:61
u_int version
Definition: print-isakmp.c:645
const char * ndo_protocol
Definition: netdissect.h:218