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 Hannes Gredler (hannes@juniper.net)
14 */
15
16#include <sys/cdefs.h>
17#ifndef lint
18#if 0
19static const char rcsid[] _U_ =
20    "@(#) Header: /tcpdump/master/tcpdump/print-bfd.c,v 1.10 2006-02-02 06:35:52 hannes Exp";
21#else
22__RCSID("$NetBSD$");
23#endif
24#endif
25
26#ifdef HAVE_CONFIG_H
27#include "config.h"
28#endif
29
30#include <tcpdump-stdinc.h>
31
32#include <stdio.h>
33#include <stdlib.h>
34
35#include "interface.h"
36#include "extract.h"
37#include "addrtoname.h"
38
39#include "udp.h"
40
41/*
42 * Control packet, BFDv0, draft-katz-ward-bfd-01.txt
43 *
44 *     0                   1                   2                   3
45 *     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
46 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
47 *    |Vers |  Diag   |H|D|P|F| Rsvd  |  Detect Mult  |    Length     |
48 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
49 *    |                       My Discriminator                        |
50 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
51 *    |                      Your Discriminator                       |
52 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
53 *    |                    Desired Min TX Interval                    |
54 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
55 *    |                   Required Min RX Interval                    |
56 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
57 *    |                 Required Min Echo RX Interval                 |
58 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
59 */
60
61/*
62 *  Control packet, BFDv1, draft-ietf-bfd-base-02.txt
63 *
64 *     0                   1                   2                   3
65 *     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
66 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
67 *    |Vers |  Diag   |Sta|P|F|C|A|D|R|  Detect Mult  |    Length     |
68 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
69 *    |                       My Discriminator                        |
70 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
71 *    |                      Your Discriminator                       |
72 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
73 *    |                    Desired Min TX Interval                    |
74 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
75 *    |                   Required Min RX Interval                    |
76 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
77 *    |                 Required Min Echo RX Interval                 |
78 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
79 */
80
81struct bfd_header_t {
82    u_int8_t version_diag;
83    u_int8_t flags;
84    u_int8_t detect_time_multiplier;
85    u_int8_t length;
86    u_int8_t my_discriminator[4];
87    u_int8_t your_discriminator[4];
88    u_int8_t desired_min_tx_interval[4];
89    u_int8_t required_min_rx_interval[4];
90    u_int8_t required_min_echo_interval[4];
91};
92
93/*
94 *    An optional Authentication Header may be present
95 *
96 *     0                   1                   2                   3
97 *     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
98 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
99 *    |   Auth Type   |   Auth Len    |    Authentication Data...     |
100 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
101 */
102
103struct bfd_auth_header_t {
104    u_int8_t auth_type;
105    u_int8_t auth_len;
106    u_int8_t auth_data;
107};
108
109static const struct tok bfd_v1_authentication_values[] = {
110    { 0,        "Reserved" },
111    { 1,        "Simple Password" },
112    { 2,        "Keyed MD5" },
113    { 3,        "Meticulous Keyed MD5" },
114    { 4,        "Keyed SHA1" },
115    { 5,        "Meticulous Keyed SHA1" },
116    { 0, NULL }
117};
118
119#define	BFD_EXTRACT_VERSION(x) (((x)&0xe0)>>5)
120#define	BFD_EXTRACT_DIAG(x)     ((x)&0x1f)
121
122static const struct tok bfd_port_values[] = {
123    { BFD_CONTROL_PORT, "Control" },
124    { BFD_ECHO_PORT,    "Echo" },
125    { 0, NULL }
126};
127
128
129static const struct tok bfd_diag_values[] = {
130    { 0, "No Diagnostic" },
131    { 1, "Control Detection Time Expired" },
132    { 2, "Echo Function Failed" },
133    { 3, "Neighbor Signaled Session Down" },
134    { 4, "Forwarding Plane Reset" },
135    { 5, "Path Down" },
136    { 6, "Concatenated Path Down" },
137    { 7, "Administratively Down" },
138    { 8, "Reverse Concatenated Path Down" },
139    { 0, NULL }
140};
141
142static const struct tok bfd_v0_flag_values[] = {
143    { 0x80,	"I Hear You" },
144    { 0x40,	"Demand" },
145    { 0x20,	"Poll" },
146    { 0x10,	"Final" },
147    { 0x08,	"Reserved" },
148    { 0x04,	"Reserved" },
149    { 0x02,	"Reserved" },
150    { 0x01,	"Reserved" },
151    { 0, NULL }
152};
153
154#define BFD_FLAG_AUTH 0x04
155
156static const struct tok bfd_v1_flag_values[] = {
157    { 0x20, "Poll" },
158    { 0x10, "Final" },
159    { 0x08, "Control Plane Independent" },
160    { BFD_FLAG_AUTH, "Authentication Present" },
161    { 0x02, "Demand" },
162    { 0x01, "Reserved" },
163    { 0, NULL }
164};
165
166static const struct tok bfd_v1_state_values[] = {
167    { 0, "AdminDown" },
168    { 1, "Down" },
169    { 2, "Init" },
170    { 3, "Up" },
171    { 0, NULL }
172};
173
174void
175bfd_print(register const u_char *pptr, register u_int len, register u_int port)
176{
177        const struct bfd_header_t *bfd_header;
178        const struct bfd_auth_header_t *bfd_auth_header;
179        u_int8_t version = 0;
180
181        bfd_header = (const struct bfd_header_t *)pptr;
182        if (port == BFD_CONTROL_PORT) {
183            TCHECK(*bfd_header);
184            version = BFD_EXTRACT_VERSION(bfd_header->version_diag);
185        } else if (port == BFD_ECHO_PORT) {
186            /* Echo is BFD v1 only */
187            version = 1;
188        }
189        switch ((port << 8) | version) {
190
191            /* BFDv0 */
192        case (BFD_CONTROL_PORT << 8):
193            if (vflag < 1 )
194            {
195                printf("BFDv%u, %s, Flags: [%s], length: %u",
196                       version,
197                       tok2str(bfd_port_values, "unknown (%u)", port),
198                       bittok2str(bfd_v0_flag_values, "none", bfd_header->flags),
199                       len);
200                return;
201            }
202
203            printf("BFDv%u, length: %u\n\t%s, Flags: [%s], Diagnostic: %s (0x%02x)",
204                   version,
205                   len,
206                   tok2str(bfd_port_values, "unknown (%u)", port),
207                   bittok2str(bfd_v0_flag_values, "none", bfd_header->flags),
208                   tok2str(bfd_diag_values,"unknown",BFD_EXTRACT_DIAG(bfd_header->version_diag)),
209                   BFD_EXTRACT_DIAG(bfd_header->version_diag));
210
211            printf("\n\tDetection Timer Multiplier: %u (%u ms Detection time), BFD Length: %u",
212                   bfd_header->detect_time_multiplier,
213                   bfd_header->detect_time_multiplier * EXTRACT_32BITS(bfd_header->desired_min_tx_interval)/1000,
214                   bfd_header->length);
215
216
217            printf("\n\tMy Discriminator: 0x%08x", EXTRACT_32BITS(bfd_header->my_discriminator));
218            printf(", Your Discriminator: 0x%08x", EXTRACT_32BITS(bfd_header->your_discriminator));
219            printf("\n\t  Desired min Tx Interval:    %4u ms", EXTRACT_32BITS(bfd_header->desired_min_tx_interval)/1000);
220            printf("\n\t  Required min Rx Interval:   %4u ms", EXTRACT_32BITS(bfd_header->required_min_rx_interval)/1000);
221            printf("\n\t  Required min Echo Interval: %4u ms", EXTRACT_32BITS(bfd_header->required_min_echo_interval)/1000);
222            break;
223
224            /* BFDv1 */
225        case (BFD_CONTROL_PORT << 8 | 1):
226            if (vflag < 1 )
227            {
228                printf("BFDv%u, %s, State %s, Flags: [%s], length: %u",
229                       version,
230                       tok2str(bfd_port_values, "unknown (%u)", port),
231                       tok2str(bfd_v1_state_values, "unknown (%u)", (bfd_header->flags & 0xc0) >> 6),
232                       bittok2str(bfd_v1_flag_values, "none", bfd_header->flags & 0x3f),
233                       len);
234                return;
235            }
236
237            printf("BFDv%u, length: %u\n\t%s, State %s, Flags: [%s], Diagnostic: %s (0x%02x)",
238                   version,
239                   len,
240                   tok2str(bfd_port_values, "unknown (%u)", port),
241                   tok2str(bfd_v1_state_values, "unknown (%u)", (bfd_header->flags & 0xc0) >> 6),
242                   bittok2str(bfd_v1_flag_values, "none", bfd_header->flags & 0x3f),
243                   tok2str(bfd_diag_values,"unknown",BFD_EXTRACT_DIAG(bfd_header->version_diag)),
244                   BFD_EXTRACT_DIAG(bfd_header->version_diag));
245
246            printf("\n\tDetection Timer Multiplier: %u (%u ms Detection time), BFD Length: %u",
247                   bfd_header->detect_time_multiplier,
248                   bfd_header->detect_time_multiplier * EXTRACT_32BITS(bfd_header->desired_min_tx_interval)/1000,
249                   bfd_header->length);
250
251
252            printf("\n\tMy Discriminator: 0x%08x", EXTRACT_32BITS(bfd_header->my_discriminator));
253            printf(", Your Discriminator: 0x%08x", EXTRACT_32BITS(bfd_header->your_discriminator));
254            printf("\n\t  Desired min Tx Interval:    %4u ms", EXTRACT_32BITS(bfd_header->desired_min_tx_interval)/1000);
255            printf("\n\t  Required min Rx Interval:   %4u ms", EXTRACT_32BITS(bfd_header->required_min_rx_interval)/1000);
256            printf("\n\t  Required min Echo Interval: %4u ms", EXTRACT_32BITS(bfd_header->required_min_echo_interval)/1000);
257
258            if (bfd_header->flags & BFD_FLAG_AUTH) {
259                pptr += sizeof (const struct bfd_header_t);
260                bfd_auth_header = (const struct bfd_auth_header_t *)pptr;
261                TCHECK2(*bfd_auth_header, sizeof(const struct bfd_auth_header_t));
262                printf("\n\t%s (%u) Authentication, length %u present",
263                       tok2str(bfd_v1_authentication_values,"Unknown",bfd_auth_header->auth_type),
264                       bfd_auth_header->auth_type,
265                       bfd_auth_header->auth_len);
266            }
267            break;
268
269            /* BFDv0 */
270        case (BFD_ECHO_PORT << 8): /* not yet supported - fall through */
271            /* BFDv1 */
272        case (BFD_ECHO_PORT << 8 | 1):
273
274        default:
275            printf("BFD, %s, length: %u",
276                   tok2str(bfd_port_values, "unknown (%u)", port),
277                   len);
278            if (vflag >= 1) {
279                if(!print_unknown_data(pptr,"\n\t",len))
280                    return;
281            }
282            break;
283        }
284        return;
285
286trunc:
287        printf("[|BFD]");
288}
289