xref: /netbsd-src/external/bsd/tcpdump/dist/print-slow.c (revision 3117ece4fc4a4ca4489ba793710b60b0d26bab6c)
1 /*
2  * Copyright (c) 1998-2006 The TCPDUMP project
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that: (1) source code
6  * distributions retain the above copyright notice and this paragraph
7  * in its entirety, and (2) distributions including binary code include
8  * the above copyright notice and this paragraph in its entirety in
9  * the documentation or other materials provided with the distribution.
10  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND
11  * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
12  * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
13  * FOR A PARTICULAR PURPOSE.
14  *
15  * support for the IEEE "slow protocols" LACP, MARKER as per 802.3ad
16  *                                       OAM as per 802.3ah
17  *
18  * Original code by Hannes Gredler (hannes@gredler.at)
19  */
20 
21 #include <sys/cdefs.h>
22 #ifndef lint
23 __RCSID("$NetBSD: print-slow.c,v 1.11 2024/09/02 16:15:33 christos Exp $");
24 #endif
25 
26 /* \summary: IEEE "slow protocols" (802.3ad/802.3ah) printer */
27 
28 #include <config.h>
29 
30 #include "netdissect-stdinc.h"
31 
32 #define ND_LONGJMP_FROM_TCHECK
33 #include "netdissect.h"
34 #include "extract.h"
35 #include "addrtoname.h"
36 #include "oui.h"
37 
38 
39 #define	SLOW_PROTO_LACP                     1
40 #define	SLOW_PROTO_MARKER                   2
41 #define SLOW_PROTO_OAM                      3
42 
43 #define	LACP_VERSION                        1
44 #define	MARKER_VERSION                      1
45 
46 static const struct tok slow_proto_values[] = {
47     { SLOW_PROTO_LACP, "LACP" },
48     { SLOW_PROTO_MARKER, "MARKER" },
49     { SLOW_PROTO_OAM, "OAM" },
50     { 0, NULL}
51 };
52 
53 static const struct tok slow_oam_flag_values[] = {
54     { 0x0001, "Link Fault" },
55     { 0x0002, "Dying Gasp" },
56     { 0x0004, "Critical Event" },
57     { 0x0008, "Local Evaluating" },
58     { 0x0010, "Local Stable" },
59     { 0x0020, "Remote Evaluating" },
60     { 0x0040, "Remote Stable" },
61     { 0, NULL}
62 };
63 
64 #define SLOW_OAM_CODE_INFO          0x00
65 #define SLOW_OAM_CODE_EVENT_NOTIF   0x01
66 #define SLOW_OAM_CODE_VAR_REQUEST   0x02
67 #define SLOW_OAM_CODE_VAR_RESPONSE  0x03
68 #define SLOW_OAM_CODE_LOOPBACK_CTRL 0x04
69 #define SLOW_OAM_CODE_PRIVATE       0xfe
70 
71 static const struct tok slow_oam_code_values[] = {
72     { SLOW_OAM_CODE_INFO, "Information" },
73     { SLOW_OAM_CODE_EVENT_NOTIF, "Event Notification" },
74     { SLOW_OAM_CODE_VAR_REQUEST, "Variable Request" },
75     { SLOW_OAM_CODE_VAR_RESPONSE, "Variable Response" },
76     { SLOW_OAM_CODE_LOOPBACK_CTRL, "Loopback Control" },
77     { SLOW_OAM_CODE_PRIVATE, "Vendor Private" },
78     { 0, NULL}
79 };
80 
81 struct slow_oam_info_t {
82     nd_uint8_t info_type;
83     nd_uint8_t info_length;
84     nd_uint8_t oam_version;
85     nd_uint16_t revision;
86     nd_uint8_t state;
87     nd_uint8_t oam_config;
88     nd_uint16_t oam_pdu_config;
89     nd_uint24_t oui;
90     nd_uint32_t vendor_private;
91 };
92 
93 #define SLOW_OAM_INFO_TYPE_END_OF_TLV 0x00
94 #define SLOW_OAM_INFO_TYPE_LOCAL 0x01
95 #define SLOW_OAM_INFO_TYPE_REMOTE 0x02
96 #define SLOW_OAM_INFO_TYPE_ORG_SPECIFIC 0xfe
97 
98 static const struct tok slow_oam_info_type_values[] = {
99     { SLOW_OAM_INFO_TYPE_END_OF_TLV, "End of TLV marker" },
100     { SLOW_OAM_INFO_TYPE_LOCAL, "Local" },
101     { SLOW_OAM_INFO_TYPE_REMOTE, "Remote" },
102     { SLOW_OAM_INFO_TYPE_ORG_SPECIFIC, "Organization specific" },
103     { 0, NULL}
104 };
105 
106 #define OAM_INFO_TYPE_PARSER_MASK 0x3
107 static const struct tok slow_oam_info_type_state_parser_values[] = {
108     { 0x00, "forwarding" },
109     { 0x01, "looping back" },
110     { 0x02, "discarding" },
111     { 0x03, "reserved" },
112     { 0, NULL}
113 };
114 
115 #define OAM_INFO_TYPE_MUX_MASK 0x4
116 static const struct tok slow_oam_info_type_state_mux_values[] = {
117     { 0x00, "forwarding" },
118     { 0x04, "discarding" },
119     { 0, NULL}
120 };
121 
122 static const struct tok slow_oam_info_type_oam_config_values[] = {
123     { 0x01, "Active" },
124     { 0x02, "Unidirectional" },
125     { 0x04, "Remote-Loopback" },
126     { 0x08, "Link-Events" },
127     { 0x10, "Variable-Retrieval" },
128     { 0, NULL}
129 };
130 
131 /* 11 Bits */
132 #define OAM_INFO_TYPE_PDU_SIZE_MASK 0x7ff
133 
134 #define SLOW_OAM_LINK_EVENT_END_OF_TLV 0x00
135 #define SLOW_OAM_LINK_EVENT_ERR_SYM_PER 0x01
136 #define SLOW_OAM_LINK_EVENT_ERR_FRM 0x02
137 #define SLOW_OAM_LINK_EVENT_ERR_FRM_PER 0x03
138 #define SLOW_OAM_LINK_EVENT_ERR_FRM_SUMM 0x04
139 #define SLOW_OAM_LINK_EVENT_ORG_SPECIFIC 0xfe
140 
141 static const struct tok slow_oam_link_event_values[] = {
142     { SLOW_OAM_LINK_EVENT_END_OF_TLV, "End of TLV marker" },
143     { SLOW_OAM_LINK_EVENT_ERR_SYM_PER, "Errored Symbol Period Event" },
144     { SLOW_OAM_LINK_EVENT_ERR_FRM, "Errored Frame Event" },
145     { SLOW_OAM_LINK_EVENT_ERR_FRM_PER, "Errored Frame Period Event" },
146     { SLOW_OAM_LINK_EVENT_ERR_FRM_SUMM, "Errored Frame Seconds Summary Event" },
147     { SLOW_OAM_LINK_EVENT_ORG_SPECIFIC, "Organization specific" },
148     { 0, NULL}
149 };
150 
151 struct slow_oam_link_event_t {
152     nd_uint8_t event_type;
153     nd_uint8_t event_length;
154     nd_uint16_t time_stamp;
155     nd_uint64_t window;
156     nd_uint64_t threshold;
157     nd_uint64_t errors;
158     nd_uint64_t errors_running_total;
159     nd_uint32_t event_running_total;
160 };
161 
162 struct slow_oam_variablerequest_t {
163     nd_uint8_t branch;
164     nd_uint16_t leaf;
165 };
166 
167 struct slow_oam_variableresponse_t {
168     nd_uint8_t branch;
169     nd_uint16_t leaf;
170     nd_uint8_t length;
171 };
172 
173 struct slow_oam_loopbackctrl_t {
174     nd_uint8_t command;
175 };
176 
177 static const struct tok slow_oam_loopbackctrl_cmd_values[] = {
178     { 0x01, "Enable OAM Remote Loopback" },
179     { 0x02, "Disable OAM Remote Loopback" },
180     { 0, NULL}
181 };
182 
183 struct tlv_header_t {
184     nd_uint8_t type;
185     nd_uint8_t length;
186 };
187 
188 #define LACP_MARKER_TLV_TERMINATOR     0x00  /* same code for LACP and Marker */
189 
190 #define LACP_TLV_ACTOR_INFO            0x01
191 #define LACP_TLV_PARTNER_INFO          0x02
192 #define LACP_TLV_COLLECTOR_INFO        0x03
193 
194 #define MARKER_TLV_MARKER_INFO         0x01
195 
196 static const struct tok slow_tlv_values[] = {
197     { (SLOW_PROTO_LACP << 8) + LACP_MARKER_TLV_TERMINATOR, "Terminator"},
198     { (SLOW_PROTO_LACP << 8) + LACP_TLV_ACTOR_INFO, "Actor Information"},
199     { (SLOW_PROTO_LACP << 8) + LACP_TLV_PARTNER_INFO, "Partner Information"},
200     { (SLOW_PROTO_LACP << 8) + LACP_TLV_COLLECTOR_INFO, "Collector Information"},
201 
202     { (SLOW_PROTO_MARKER << 8) + LACP_MARKER_TLV_TERMINATOR, "Terminator"},
203     { (SLOW_PROTO_MARKER << 8) + MARKER_TLV_MARKER_INFO, "Marker Information"},
204     { 0, NULL}
205 };
206 
207 struct lacp_tlv_actor_partner_info_t {
208     nd_uint16_t sys_pri;
209     nd_mac_addr sys;
210     nd_uint16_t key;
211     nd_uint16_t port_pri;
212     nd_uint16_t port;
213     nd_uint8_t state;
214     nd_byte    pad[3];
215 };
216 
217 static const struct tok lacp_tlv_actor_partner_info_state_values[] = {
218     { 0x01, "Activity"},
219     { 0x02, "Timeout"},
220     { 0x04, "Aggregation"},
221     { 0x08, "Synchronization"},
222     { 0x10, "Collecting"},
223     { 0x20, "Distributing"},
224     { 0x40, "Default"},
225     { 0x80, "Expired"},
226     { 0, NULL}
227 };
228 
229 struct lacp_tlv_collector_info_t {
230     nd_uint16_t max_delay;
231     nd_byte     pad[12];
232 };
233 
234 struct marker_tlv_marker_info_t {
235     nd_uint16_t req_port;
236     nd_mac_addr req_sys;
237     nd_uint32_t req_trans_id;
238     nd_byte     pad[2];
239 };
240 
241 struct lacp_marker_tlv_terminator_t {
242     nd_byte     pad[50];
243 };
244 
245 static void slow_marker_lacp_print(netdissect_options *, const u_char *, u_int, u_int);
246 static void slow_oam_print(netdissect_options *, const u_char *, u_int);
247 
248 void
249 slow_print(netdissect_options *ndo,
250            const u_char *pptr, u_int len)
251 {
252     int print_version;
253     u_int subtype;
254 
255     ndo->ndo_protocol = "slow";
256     if (len < 1)
257         goto tooshort;
258     subtype = GET_U_1(pptr);
259 
260     /*
261      * Sanity checking of the header.
262      */
263     switch (subtype) {
264     case SLOW_PROTO_LACP:
265         if (len < 2)
266             goto tooshort;
267         if (GET_U_1(pptr + 1) != LACP_VERSION) {
268             ND_PRINT("LACP version %u packet not supported",
269                      GET_U_1(pptr + 1));
270             return;
271         }
272         print_version = 1;
273         break;
274 
275     case SLOW_PROTO_MARKER:
276         if (len < 2)
277             goto tooshort;
278         if (GET_U_1(pptr + 1) != MARKER_VERSION) {
279             ND_PRINT("MARKER version %u packet not supported",
280                      GET_U_1(pptr + 1));
281             return;
282         }
283         print_version = 1;
284         break;
285 
286     case SLOW_PROTO_OAM: /* fall through */
287         print_version = 0;
288         break;
289 
290     default:
291         /* print basic information and exit */
292         print_version = -1;
293         break;
294     }
295 
296     if (print_version == 1) {
297         ND_PRINT("%sv%u, length %u",
298                tok2str(slow_proto_values, "unknown (%u)", subtype),
299                GET_U_1((pptr + 1)),
300                len);
301     } else {
302         /* some slow protos don't have a version number in the header */
303         ND_PRINT("%s, length %u",
304                tok2str(slow_proto_values, "unknown (%u)", subtype),
305                len);
306     }
307 
308     /* unrecognized subtype */
309     if (print_version == -1) {
310         print_unknown_data(ndo, pptr, "\n\t", len);
311         return;
312     }
313 
314     if (!ndo->ndo_vflag)
315         return;
316 
317     switch (subtype) {
318     default: /* should not happen */
319         break;
320 
321     case SLOW_PROTO_OAM:
322         /* skip subtype */
323         len -= 1;
324         pptr += 1;
325         slow_oam_print(ndo, pptr, len);
326         break;
327 
328     case SLOW_PROTO_LACP:   /* LACP and MARKER share the same semantics */
329     case SLOW_PROTO_MARKER:
330         /* skip subtype and version */
331         len -= 2;
332         pptr += 2;
333         slow_marker_lacp_print(ndo, pptr, len, subtype);
334         break;
335     }
336     return;
337 
338 tooshort:
339     if (!ndo->ndo_vflag)
340         ND_PRINT(" (packet is too short)");
341     else
342         ND_PRINT("\n\t\t packet is too short");
343 }
344 
345 static void
346 slow_marker_lacp_print(netdissect_options *ndo,
347                        const u_char *tptr, u_int tlen,
348                        u_int proto_subtype)
349 {
350     const struct tlv_header_t *tlv_header;
351     const u_char *tlv_tptr;
352     u_int tlv_type, tlv_len, tlv_tlen;
353 
354     union {
355         const struct lacp_marker_tlv_terminator_t *lacp_marker_tlv_terminator;
356         const struct lacp_tlv_actor_partner_info_t *lacp_tlv_actor_partner_info;
357         const struct lacp_tlv_collector_info_t *lacp_tlv_collector_info;
358         const struct marker_tlv_marker_info_t *marker_tlv_marker_info;
359     } tlv_ptr;
360 
361     while(tlen>0) {
362         /* is the packet big enough to include the tlv header ? */
363         if (tlen < sizeof(struct tlv_header_t))
364             goto tooshort;
365         /* did we capture enough for fully decoding the tlv header ? */
366         tlv_header = (const struct tlv_header_t *)tptr;
367         tlv_type = GET_U_1(tlv_header->type);
368         tlv_len = GET_U_1(tlv_header->length);
369 
370         ND_PRINT("\n\t%s TLV (0x%02x), length %u",
371                tok2str(slow_tlv_values,
372                        "Unknown",
373                        (proto_subtype << 8) + tlv_type),
374                tlv_type,
375                tlv_len);
376 
377         if (tlv_type == LACP_MARKER_TLV_TERMINATOR) {
378             /*
379              * This TLV has a length of zero, and means there are no
380              * more TLVs to process.
381              */
382             return;
383         }
384 
385         /* length includes the type and length fields */
386         if (tlv_len < sizeof(struct tlv_header_t)) {
387             ND_PRINT("\n\t    ERROR: illegal length - should be >= %zu",
388                      sizeof(struct tlv_header_t));
389             return;
390         }
391 
392         /* is the packet big enough to include the tlv ? */
393         if (tlen < tlv_len)
394             goto tooshort;
395         /* did we capture enough for fully decoding the tlv ? */
396         ND_TCHECK_LEN(tptr, tlv_len);
397 
398         tlv_tptr=tptr+sizeof(struct tlv_header_t);
399         tlv_tlen=tlv_len-sizeof(struct tlv_header_t);
400 
401         switch((proto_subtype << 8) + tlv_type) {
402 
403             /* those two TLVs have the same structure -> fall through */
404         case ((SLOW_PROTO_LACP << 8) + LACP_TLV_ACTOR_INFO):
405         case ((SLOW_PROTO_LACP << 8) + LACP_TLV_PARTNER_INFO):
406             if (tlv_tlen !=
407                 sizeof(struct lacp_tlv_actor_partner_info_t)) {
408                 ND_PRINT("\n\t    ERROR: illegal length - should be %zu",
409                          sizeof(struct tlv_header_t) + sizeof(struct lacp_tlv_actor_partner_info_t));
410                 goto badlength;
411             }
412 
413             tlv_ptr.lacp_tlv_actor_partner_info = (const struct lacp_tlv_actor_partner_info_t *)tlv_tptr;
414 
415             ND_PRINT("\n\t  System %s, System Priority %u, Key %u"
416                    ", Port %u, Port Priority %u\n\t  State Flags [%s]",
417                    GET_ETHERADDR_STRING(tlv_ptr.lacp_tlv_actor_partner_info->sys),
418                    GET_BE_U_2(tlv_ptr.lacp_tlv_actor_partner_info->sys_pri),
419                    GET_BE_U_2(tlv_ptr.lacp_tlv_actor_partner_info->key),
420                    GET_BE_U_2(tlv_ptr.lacp_tlv_actor_partner_info->port),
421                    GET_BE_U_2(tlv_ptr.lacp_tlv_actor_partner_info->port_pri),
422                    bittok2str(lacp_tlv_actor_partner_info_state_values,
423                               "none",
424                               GET_U_1(tlv_ptr.lacp_tlv_actor_partner_info->state)));
425 
426             break;
427 
428         case ((SLOW_PROTO_LACP << 8) + LACP_TLV_COLLECTOR_INFO):
429             if (tlv_tlen !=
430                 sizeof(struct lacp_tlv_collector_info_t)) {
431                 ND_PRINT("\n\t    ERROR: illegal length - should be %zu",
432                          sizeof(struct tlv_header_t) + sizeof(struct lacp_tlv_collector_info_t));
433                 goto badlength;
434             }
435 
436             tlv_ptr.lacp_tlv_collector_info = (const struct lacp_tlv_collector_info_t *)tlv_tptr;
437 
438             ND_PRINT("\n\t  Max Delay %u",
439                    GET_BE_U_2(tlv_ptr.lacp_tlv_collector_info->max_delay));
440 
441             break;
442 
443         case ((SLOW_PROTO_MARKER << 8) + MARKER_TLV_MARKER_INFO):
444             if (tlv_tlen !=
445                 sizeof(struct marker_tlv_marker_info_t)) {
446                 ND_PRINT("\n\t    ERROR: illegal length - should be %zu",
447                          sizeof(struct tlv_header_t) + sizeof(struct marker_tlv_marker_info_t));
448                 goto badlength;
449             }
450 
451             tlv_ptr.marker_tlv_marker_info = (const struct marker_tlv_marker_info_t *)tlv_tptr;
452 
453             ND_PRINT("\n\t  Request System %s, Request Port %u, Request Transaction ID 0x%08x",
454                    GET_ETHERADDR_STRING(tlv_ptr.marker_tlv_marker_info->req_sys),
455                    GET_BE_U_2(tlv_ptr.marker_tlv_marker_info->req_port),
456                    GET_BE_U_4(tlv_ptr.marker_tlv_marker_info->req_trans_id));
457 
458             break;
459 
460         default:
461             if (ndo->ndo_vflag <= 1)
462                 print_unknown_data(ndo, tlv_tptr, "\n\t  ", tlv_tlen);
463             break;
464         }
465 
466     badlength:
467         /* do we want to see an additional hexdump ? */
468         if (ndo->ndo_vflag > 1) {
469             print_unknown_data(ndo, tptr+sizeof(struct tlv_header_t), "\n\t  ",
470                                tlv_len-sizeof(struct tlv_header_t));
471         }
472 
473         tptr+=tlv_len;
474         tlen-=tlv_len;
475     }
476     return;
477 
478 tooshort:
479     ND_PRINT("\n\t\t packet is too short");
480 }
481 
482 static void
483 slow_oam_print(netdissect_options *ndo,
484                const u_char *tptr, u_int tlen)
485 {
486     uint8_t code;
487     uint8_t type, length;
488     uint8_t state;
489     uint8_t command;
490     u_int hexdump;
491 
492     struct slow_oam_common_header_t {
493         nd_uint16_t flags;
494         nd_uint8_t code;
495     };
496 
497     struct slow_oam_tlv_header_t {
498         nd_uint8_t type;
499         nd_uint8_t length;
500     };
501 
502     union {
503         const struct slow_oam_common_header_t *slow_oam_common_header;
504         const struct slow_oam_tlv_header_t *slow_oam_tlv_header;
505     } ptr;
506 
507     union {
508         const struct slow_oam_info_t *slow_oam_info;
509         const struct slow_oam_link_event_t *slow_oam_link_event;
510         const struct slow_oam_variablerequest_t *slow_oam_variablerequest;
511         const struct slow_oam_variableresponse_t *slow_oam_variableresponse;
512         const struct slow_oam_loopbackctrl_t *slow_oam_loopbackctrl;
513     } tlv;
514 
515     ptr.slow_oam_common_header = (const struct slow_oam_common_header_t *)tptr;
516     if (tlen < sizeof(*ptr.slow_oam_common_header))
517         goto tooshort;
518     ND_TCHECK_SIZE(ptr.slow_oam_common_header);
519     tptr += sizeof(struct slow_oam_common_header_t);
520     tlen -= sizeof(struct slow_oam_common_header_t);
521 
522     code = GET_U_1(ptr.slow_oam_common_header->code);
523     ND_PRINT("\n\tCode %s OAM PDU, Flags [%s]",
524            tok2str(slow_oam_code_values, "Unknown (%u)", code),
525            bittok2str(slow_oam_flag_values,
526                       "none",
527                       GET_BE_U_2(ptr.slow_oam_common_header->flags)));
528 
529     switch (code) {
530     case SLOW_OAM_CODE_INFO:
531         while (tlen > 0) {
532             ptr.slow_oam_tlv_header = (const struct slow_oam_tlv_header_t *)tptr;
533             if (tlen < sizeof(*ptr.slow_oam_tlv_header))
534                 goto tooshort;
535             ND_TCHECK_SIZE(ptr.slow_oam_tlv_header);
536             type = GET_U_1(ptr.slow_oam_tlv_header->type);
537             length = GET_U_1(ptr.slow_oam_tlv_header->length);
538             ND_PRINT("\n\t  %s Information Type (%u), length %u",
539                    tok2str(slow_oam_info_type_values, "Reserved", type),
540                    type,
541                    length);
542 
543             if (type == SLOW_OAM_INFO_TYPE_END_OF_TLV) {
544                 /*
545                  * As IEEE Std 802.3-2015 says for the End of TLV Marker,
546                  * "(the length and value of the Type 0x00 TLV can be ignored)".
547                  */
548                 return;
549             }
550 
551             /* length includes the type and length fields */
552             if (length < sizeof(struct slow_oam_tlv_header_t)) {
553                 ND_PRINT("\n\t    ERROR: illegal length - should be >= %zu",
554                          sizeof(struct slow_oam_tlv_header_t));
555                 return;
556             }
557 
558             if (tlen < length)
559                 goto tooshort;
560             ND_TCHECK_LEN(tptr, length);
561 
562             hexdump = FALSE;
563             switch (type) {
564             case SLOW_OAM_INFO_TYPE_LOCAL: /* identical format - fall through */
565             case SLOW_OAM_INFO_TYPE_REMOTE:
566                 tlv.slow_oam_info = (const struct slow_oam_info_t *)tptr;
567 
568                 if (GET_U_1(tlv.slow_oam_info->info_length) !=
569                     sizeof(struct slow_oam_info_t)) {
570                     ND_PRINT("\n\t    ERROR: illegal length - should be %zu",
571                            sizeof(struct slow_oam_info_t));
572                     hexdump = TRUE;
573                     goto badlength_code_info;
574                 }
575 
576                 ND_PRINT("\n\t    OAM-Version %u, Revision %u",
577                        GET_U_1(tlv.slow_oam_info->oam_version),
578                        GET_BE_U_2(tlv.slow_oam_info->revision));
579 
580                 state = GET_U_1(tlv.slow_oam_info->state);
581                 ND_PRINT("\n\t    State-Parser-Action %s, State-MUX-Action %s",
582                        tok2str(slow_oam_info_type_state_parser_values, "Reserved",
583                                state & OAM_INFO_TYPE_PARSER_MASK),
584                        tok2str(slow_oam_info_type_state_mux_values, "Reserved",
585                                state & OAM_INFO_TYPE_MUX_MASK));
586                 ND_PRINT("\n\t    OAM-Config Flags [%s], OAM-PDU-Config max-PDU size %u",
587                        bittok2str(slow_oam_info_type_oam_config_values, "none",
588                                   GET_U_1(tlv.slow_oam_info->oam_config)),
589                        GET_BE_U_2(tlv.slow_oam_info->oam_pdu_config) &
590                        OAM_INFO_TYPE_PDU_SIZE_MASK);
591                 ND_PRINT("\n\t    OUI %s (0x%06x), Vendor-Private 0x%08x",
592                        tok2str(oui_values, "Unknown",
593                                GET_BE_U_3(tlv.slow_oam_info->oui)),
594                        GET_BE_U_3(tlv.slow_oam_info->oui),
595                        GET_BE_U_4(tlv.slow_oam_info->vendor_private));
596                 break;
597 
598             case SLOW_OAM_INFO_TYPE_ORG_SPECIFIC:
599                 hexdump = TRUE;
600                 break;
601 
602             default:
603                 hexdump = TRUE;
604                 break;
605             }
606 
607         badlength_code_info:
608             /* do we also want to see a hex dump ? */
609             if (ndo->ndo_vflag > 1 || hexdump==TRUE) {
610                 print_unknown_data(ndo, tptr, "\n\t  ",
611                                    length);
612             }
613 
614             tlen -= length;
615             tptr += length;
616         }
617         break;
618 
619     case SLOW_OAM_CODE_EVENT_NOTIF:
620         /* Sequence number */
621         if (tlen < 2)
622             goto tooshort;
623         ND_PRINT("\n\t  Sequence Number %u", GET_BE_U_2(tptr));
624         tlen -= 2;
625         tptr += 2;
626 
627         /* TLVs */
628         while (tlen > 0) {
629             ptr.slow_oam_tlv_header = (const struct slow_oam_tlv_header_t *)tptr;
630             if (tlen < sizeof(*ptr.slow_oam_tlv_header))
631                 goto tooshort;
632             type = GET_U_1(ptr.slow_oam_tlv_header->type);
633             length = GET_U_1(ptr.slow_oam_tlv_header->length);
634             ND_PRINT("\n\t  %s Link Event Type (%u), length %u",
635                    tok2str(slow_oam_link_event_values, "Reserved",
636                            type),
637                    type,
638                    length);
639 
640             if (type == SLOW_OAM_INFO_TYPE_END_OF_TLV) {
641                 /*
642                  * As IEEE Std 802.3-2015 says for the End of TLV Marker,
643                  * "(the length and value of the Type 0x00 TLV can be ignored)".
644                  */
645                 return;
646             }
647 
648             /* length includes the type and length fields */
649             if (length < sizeof(struct slow_oam_tlv_header_t)) {
650                 ND_PRINT("\n\t    ERROR: illegal length - should be >= %zu",
651                          sizeof(struct slow_oam_tlv_header_t));
652                 return;
653             }
654 
655             if (tlen < length)
656                 goto tooshort;
657             ND_TCHECK_LEN(tptr, length);
658 
659             hexdump = FALSE;
660             switch (type) {
661             case SLOW_OAM_LINK_EVENT_ERR_SYM_PER: /* identical format - fall through */
662             case SLOW_OAM_LINK_EVENT_ERR_FRM:
663             case SLOW_OAM_LINK_EVENT_ERR_FRM_PER:
664             case SLOW_OAM_LINK_EVENT_ERR_FRM_SUMM:
665                 tlv.slow_oam_link_event = (const struct slow_oam_link_event_t *)tptr;
666 
667                 if (GET_U_1(tlv.slow_oam_link_event->event_length) !=
668                     sizeof(struct slow_oam_link_event_t)) {
669                     ND_PRINT("\n\t    ERROR: illegal length - should be %zu",
670                              sizeof(struct slow_oam_link_event_t));
671                     hexdump = TRUE;
672                     goto badlength_event_notif;
673                 }
674 
675                 ND_PRINT("\n\t    Timestamp %u ms, Errored Window %" PRIu64
676                        "\n\t    Errored Threshold %" PRIu64
677                        "\n\t    Errors %" PRIu64
678                        "\n\t    Error Running Total %" PRIu64
679                        "\n\t    Event Running Total %u",
680                        GET_BE_U_2(tlv.slow_oam_link_event->time_stamp)*100,
681                        GET_BE_U_8(tlv.slow_oam_link_event->window),
682                        GET_BE_U_8(tlv.slow_oam_link_event->threshold),
683                        GET_BE_U_8(tlv.slow_oam_link_event->errors),
684                        GET_BE_U_8(tlv.slow_oam_link_event->errors_running_total),
685                        GET_BE_U_4(tlv.slow_oam_link_event->event_running_total));
686                 break;
687 
688             case SLOW_OAM_LINK_EVENT_ORG_SPECIFIC:
689                 hexdump = TRUE;
690                 break;
691 
692             default:
693                 hexdump = TRUE;
694                 break;
695             }
696 
697         badlength_event_notif:
698             /* do we also want to see a hex dump ? */
699             if (ndo->ndo_vflag > 1 || hexdump==TRUE) {
700                 print_unknown_data(ndo, tptr, "\n\t  ",
701                                    length);
702             }
703 
704             tlen -= length;
705             tptr += length;
706         }
707         break;
708 
709     case SLOW_OAM_CODE_LOOPBACK_CTRL:
710         tlv.slow_oam_loopbackctrl = (const struct slow_oam_loopbackctrl_t *)tptr;
711         if (tlen < sizeof(*tlv.slow_oam_loopbackctrl))
712             goto tooshort;
713         command = GET_U_1(tlv.slow_oam_loopbackctrl->command);
714         ND_PRINT("\n\t  Command %s (%u)",
715                tok2str(slow_oam_loopbackctrl_cmd_values,
716                        "Unknown",
717                        command),
718                command);
719         tptr ++;
720         tlen --;
721         break;
722 
723         /*
724          * FIXME those are the defined codes that lack a decoder
725          * you are welcome to contribute code ;-)
726          */
727     case SLOW_OAM_CODE_VAR_REQUEST:
728     case SLOW_OAM_CODE_VAR_RESPONSE:
729     case SLOW_OAM_CODE_PRIVATE:
730     default:
731         if (ndo->ndo_vflag <= 1) {
732             print_unknown_data(ndo, tptr, "\n\t  ", tlen);
733         }
734         break;
735     }
736     return;
737 
738 tooshort:
739     ND_PRINT("\n\t\t packet is too short");
740 }
741