1 /*
2  * Copyright (c) 1994, 1995, 1996, 1997
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that: (1) source code distributions
7  * retain the above copyright notice and this paragraph in its entirety, (2)
8  * distributions including binary code include the above copyright notice and
9  * this paragraph in its entirety in the documentation or other materials
10  * provided with the distribution, and (3) all advertising materials mentioning
11  * features or use of this software display the following acknowledgement:
12  * ``This product includes software developed by the University of California,
13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14  * the University nor the names of its contributors may be used to endorse
15  * or promote products derived from this software without specific prior
16  * written permission.
17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20  */
21 
22 #define NETDISSECT_REWORKED
23 #ifdef HAVE_CONFIG_H
24 #include "config.h"
25 #endif
26 
27 #include <tcpdump-stdinc.h>
28 
29 #include "interface.h"
30 #include "extract.h"
31 #include "addrtoname.h"
32 #include "atm.h"
33 #include "atmuni31.h"
34 #include "llc.h"
35 
36 static const char tstr[] = "[|atm]";
37 
38 #define OAM_CRC10_MASK 0x3ff
39 #define OAM_PAYLOAD_LEN 48
40 #define OAM_FUNCTION_SPECIFIC_LEN 45 /* this excludes crc10 and cell-type/function-type */
41 #define OAM_CELLTYPE_FUNCTYPE_LEN 1
42 
43 static const struct tok oam_f_values[] = {
44     { VCI_OAMF4SC, "OAM F4 (segment)" },
45     { VCI_OAMF4EC, "OAM F4 (end)" },
46     { 0, NULL }
47 };
48 
49 static const struct tok atm_pty_values[] = {
50     { 0x0, "user data, uncongested, SDU 0" },
51     { 0x1, "user data, uncongested, SDU 1" },
52     { 0x2, "user data, congested, SDU 0" },
53     { 0x3, "user data, congested, SDU 1" },
54     { 0x4, "VCC OAM F5 flow segment" },
55     { 0x5, "VCC OAM F5 flow end-to-end" },
56     { 0x6, "Traffic Control and resource Mgmt" },
57     { 0, NULL }
58 };
59 
60 #define OAM_CELLTYPE_FM 0x1
61 #define OAM_CELLTYPE_PM 0x2
62 #define OAM_CELLTYPE_AD 0x8
63 #define OAM_CELLTYPE_SM 0xf
64 
65 static const struct tok oam_celltype_values[] = {
66     { OAM_CELLTYPE_FM, "Fault Management" },
67     { OAM_CELLTYPE_PM, "Performance Management" },
68     { OAM_CELLTYPE_AD, "activate/deactivate" },
69     { OAM_CELLTYPE_SM, "System Management" },
70     { 0, NULL }
71 };
72 
73 #define OAM_FM_FUNCTYPE_AIS       0x0
74 #define OAM_FM_FUNCTYPE_RDI       0x1
75 #define OAM_FM_FUNCTYPE_CONTCHECK 0x4
76 #define OAM_FM_FUNCTYPE_LOOPBACK  0x8
77 
78 static const struct tok oam_fm_functype_values[] = {
79     { OAM_FM_FUNCTYPE_AIS, "AIS" },
80     { OAM_FM_FUNCTYPE_RDI, "RDI" },
81     { OAM_FM_FUNCTYPE_CONTCHECK, "Continuity Check" },
82     { OAM_FM_FUNCTYPE_LOOPBACK, "Loopback" },
83     { 0, NULL }
84 };
85 
86 static const struct tok oam_pm_functype_values[] = {
87     { 0x0, "Forward Monitoring" },
88     { 0x1, "Backward Reporting" },
89     { 0x2, "Monitoring and Reporting" },
90     { 0, NULL }
91 };
92 
93 static const struct tok oam_ad_functype_values[] = {
94     { 0x0, "Performance Monitoring" },
95     { 0x1, "Continuity Check" },
96     { 0, NULL }
97 };
98 
99 #define OAM_FM_LOOPBACK_INDICATOR_MASK 0x1
100 
101 static const struct tok oam_fm_loopback_indicator_values[] = {
102     { 0x0, "Reply" },
103     { 0x1, "Request" },
104     { 0, NULL }
105 };
106 
107 static const struct tok *oam_functype_values[16] = {
108     NULL,
109     oam_fm_functype_values, /* 1 */
110     oam_pm_functype_values, /* 2 */
111     NULL,
112     NULL,
113     NULL,
114     NULL,
115     NULL,
116     oam_ad_functype_values, /* 8 */
117     NULL,
118     NULL,
119     NULL,
120     NULL,
121     NULL,
122     NULL,
123     NULL
124 };
125 
126 /*
127  * Print an RFC 1483 LLC-encapsulated ATM frame.
128  */
129 static void
atm_llc_print(netdissect_options * ndo,const u_char * p,int length,int caplen)130 atm_llc_print(netdissect_options *ndo,
131               const u_char *p, int length, int caplen)
132 {
133 	u_short extracted_ethertype;
134 
135 	if (!llc_print(ndo, p, length, caplen, NULL, NULL,
136 	    &extracted_ethertype)) {
137 		/* ether_type not known, print raw packet */
138 		if (extracted_ethertype) {
139 			ND_PRINT((ndo, "(LLC %s) ",
140 		etherproto_string(htons(extracted_ethertype))));
141 		}
142 		if (!ndo->ndo_suppress_default_print)
143 			ND_DEFAULTPRINT(p, caplen);
144 	}
145 }
146 
147 /*
148  * Given a SAP value, generate the LLC header value for a UI packet
149  * with that SAP as the source and destination SAP.
150  */
151 #define LLC_UI_HDR(sap)	((sap)<<16 | (sap<<8) | 0x03)
152 
153 /*
154  * This is the top level routine of the printer.  'p' points
155  * to the LLC/SNAP header of the packet, 'h->ts' is the timestamp,
156  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
157  * is the number of bytes actually captured.
158  */
159 u_int
atm_if_print(netdissect_options * ndo,const struct pcap_pkthdr * h,const u_char * p)160 atm_if_print(netdissect_options *ndo,
161              const struct pcap_pkthdr *h, const u_char *p)
162 {
163 	u_int caplen = h->caplen;
164 	u_int length = h->len;
165 	uint32_t llchdr;
166 	u_int hdrlen = 0;
167 
168 	if (caplen < 1 || length < 1) {
169 		ND_PRINT((ndo, "%s", tstr));
170 		return (caplen);
171 	}
172 
173         /* Cisco Style NLPID ? */
174         if (*p == LLC_UI) {
175             if (ndo->ndo_eflag)
176                 ND_PRINT((ndo, "CNLPID "));
177             isoclns_print(ndo, p + 1, length - 1, caplen - 1);
178             return hdrlen;
179         }
180 
181 	/*
182 	 * Must have at least a DSAP, an SSAP, and the first byte of the
183 	 * control field.
184 	 */
185 	if (caplen < 3 || length < 3) {
186 		ND_PRINT((ndo, "%s", tstr));
187 		return (caplen);
188 	}
189 
190 	/*
191 	 * Extract the presumed LLC header into a variable, for quick
192 	 * testing.
193 	 * Then check for a header that's neither a header for a SNAP
194 	 * packet nor an RFC 2684 routed NLPID-formatted PDU nor
195 	 * an 802.2-but-no-SNAP IP packet.
196 	 */
197 	llchdr = EXTRACT_24BITS(p);
198 	if (llchdr != LLC_UI_HDR(LLCSAP_SNAP) &&
199 	    llchdr != LLC_UI_HDR(LLCSAP_ISONS) &&
200 	    llchdr != LLC_UI_HDR(LLCSAP_IP)) {
201 		/*
202 		 * XXX - assume 802.6 MAC header from Fore driver.
203 		 *
204 		 * Unfortunately, the above list doesn't check for
205 		 * all known SAPs, doesn't check for headers where
206 		 * the source and destination SAP aren't the same,
207 		 * and doesn't check for non-UI frames.  It also
208 		 * runs the risk of an 802.6 MAC header that happens
209 		 * to begin with one of those values being
210 		 * incorrectly treated as an 802.2 header.
211 		 *
212 		 * So is that Fore driver still around?  And, if so,
213 		 * is it still putting 802.6 MAC headers on ATM
214 		 * packets?  If so, could it be changed to use a
215 		 * new DLT_IEEE802_6 value if we added it?
216 		 */
217 		if (caplen < 20 || length < 20) {
218 			ND_PRINT((ndo, "%s", tstr));
219 			return (caplen);
220 		}
221 		if (ndo->ndo_eflag)
222 			ND_PRINT((ndo, "%08x%08x %08x%08x ",
223 			       EXTRACT_32BITS(p),
224 			       EXTRACT_32BITS(p+4),
225 			       EXTRACT_32BITS(p+8),
226 			       EXTRACT_32BITS(p+12)));
227 		p += 20;
228 		length -= 20;
229 		caplen -= 20;
230 		hdrlen += 20;
231 	}
232 	atm_llc_print(ndo, p, length, caplen);
233 	return (hdrlen);
234 }
235 
236 /*
237  * ATM signalling.
238  */
239 static const struct tok msgtype2str[] = {
240 	{ CALL_PROCEED,		"Call_proceeding" },
241 	{ CONNECT,		"Connect" },
242 	{ CONNECT_ACK,		"Connect_ack" },
243 	{ SETUP,		"Setup" },
244 	{ RELEASE,		"Release" },
245 	{ RELEASE_DONE,		"Release_complete" },
246 	{ RESTART,		"Restart" },
247 	{ RESTART_ACK,		"Restart_ack" },
248 	{ STATUS,		"Status" },
249 	{ STATUS_ENQ,		"Status_enquiry" },
250 	{ ADD_PARTY,		"Add_party" },
251 	{ ADD_PARTY_ACK,	"Add_party_ack" },
252 	{ ADD_PARTY_REJ,	"Add_party_reject" },
253 	{ DROP_PARTY,		"Drop_party" },
254 	{ DROP_PARTY_ACK,	"Drop_party_ack" },
255 	{ 0,			NULL }
256 };
257 
258 static void
sig_print(netdissect_options * ndo,const u_char * p,int caplen)259 sig_print(netdissect_options *ndo,
260           const u_char *p, int caplen)
261 {
262 	uint32_t call_ref;
263 
264 	if (caplen < PROTO_POS) {
265 		ND_PRINT((ndo, "%s", tstr));
266 		return;
267 	}
268 	if (p[PROTO_POS] == Q2931) {
269 		/*
270 		 * protocol:Q.2931 for User to Network Interface
271 		 * (UNI 3.1) signalling
272 		 */
273 		ND_PRINT((ndo, "Q.2931"));
274 		if (caplen < MSG_TYPE_POS) {
275 			ND_PRINT((ndo, " %s", tstr));
276 			return;
277 		}
278 		ND_PRINT((ndo, ":%s ",
279 		    tok2str(msgtype2str, "msgtype#%d", p[MSG_TYPE_POS])));
280 
281 		/*
282 		 * The call reference comes before the message type,
283 		 * so if we know we have the message type, which we
284 		 * do from the caplen test above, we also know we have
285 		 * the call reference.
286 		 */
287 		call_ref = EXTRACT_24BITS(&p[CALL_REF_POS]);
288 		ND_PRINT((ndo, "CALL_REF:0x%06x", call_ref));
289 	} else {
290 		/* SCCOP with some unknown protocol atop it */
291 		ND_PRINT((ndo, "SSCOP, proto %d ", p[PROTO_POS]));
292 	}
293 }
294 
295 /*
296  * Print an ATM PDU (such as an AAL5 PDU).
297  */
298 void
atm_print(netdissect_options * ndo,u_int vpi,u_int vci,u_int traftype,const u_char * p,u_int length,u_int caplen)299 atm_print(netdissect_options *ndo,
300           u_int vpi, u_int vci, u_int traftype, const u_char *p, u_int length,
301           u_int caplen)
302 {
303 	if (ndo->ndo_eflag)
304 		ND_PRINT((ndo, "VPI:%u VCI:%u ", vpi, vci));
305 
306 	if (vpi == 0) {
307 		switch (vci) {
308 
309 		case VCI_PPC:
310 			sig_print(ndo, p, caplen);
311 			return;
312 
313 		case VCI_BCC:
314 			ND_PRINT((ndo, "broadcast sig: "));
315 			return;
316 
317 		case VCI_OAMF4SC: /* fall through */
318 		case VCI_OAMF4EC:
319 			oam_print(ndo, p, length, ATM_OAM_HEC);
320 			return;
321 
322 		case VCI_METAC:
323 			ND_PRINT((ndo, "meta: "));
324 			return;
325 
326 		case VCI_ILMIC:
327 			ND_PRINT((ndo, "ilmi: "));
328 			snmp_print(ndo, p, length);
329 			return;
330 		}
331 	}
332 
333 	switch (traftype) {
334 
335 	case ATM_LLC:
336 	default:
337 		/*
338 		 * Assumes traffic is LLC if unknown.
339 		 */
340 		atm_llc_print(ndo, p, length, caplen);
341 		break;
342 
343 	case ATM_LANE:
344 		lane_print(ndo, p, length, caplen);
345 		break;
346 	}
347 }
348 
349 struct oam_fm_loopback_t {
350     uint8_t loopback_indicator;
351     uint8_t correlation_tag[4];
352     uint8_t loopback_id[12];
353     uint8_t source_id[12];
354     uint8_t unused[16];
355 };
356 
357 struct oam_fm_ais_rdi_t {
358     uint8_t failure_type;
359     uint8_t failure_location[16];
360     uint8_t unused[28];
361 };
362 
363 int
oam_print(netdissect_options * ndo,const u_char * p,u_int length,u_int hec)364 oam_print (netdissect_options *ndo,
365            const u_char *p, u_int length, u_int hec)
366 {
367     uint32_t cell_header;
368     uint16_t vpi, vci, cksum, cksum_shouldbe, idx;
369     uint8_t  cell_type, func_type, payload, clp;
370 
371     union {
372         const struct oam_fm_loopback_t *oam_fm_loopback;
373         const struct oam_fm_ais_rdi_t *oam_fm_ais_rdi;
374     } oam_ptr;
375 
376 
377     cell_header = EXTRACT_32BITS(p+hec);
378     cell_type = ((*(p+ATM_HDR_LEN_NOHEC+hec))>>4) & 0x0f;
379     func_type = (*(p+ATM_HDR_LEN_NOHEC+hec)) & 0x0f;
380 
381     vpi = (cell_header>>20)&0xff;
382     vci = (cell_header>>4)&0xffff;
383     payload = (cell_header>>1)&0x7;
384     clp = cell_header&0x1;
385 
386     ND_PRINT((ndo, "%s, vpi %u, vci %u, payload [ %s ], clp %u, length %u",
387            tok2str(oam_f_values, "OAM F5", vci),
388            vpi, vci,
389            tok2str(atm_pty_values, "Unknown", payload),
390            clp, length));
391 
392     if (!ndo->ndo_vflag) {
393         return 1;
394     }
395 
396     ND_PRINT((ndo, "\n\tcell-type %s (%u)",
397            tok2str(oam_celltype_values, "unknown", cell_type),
398            cell_type));
399 
400     if (oam_functype_values[cell_type] == NULL)
401         ND_PRINT((ndo, ", func-type unknown (%u)", func_type));
402     else
403         ND_PRINT((ndo, ", func-type %s (%u)",
404                tok2str(oam_functype_values[cell_type],"none",func_type),
405                func_type));
406 
407     p += ATM_HDR_LEN_NOHEC + hec;
408 
409     switch (cell_type << 4 | func_type) {
410     case (OAM_CELLTYPE_FM << 4 | OAM_FM_FUNCTYPE_LOOPBACK):
411         oam_ptr.oam_fm_loopback = (const struct oam_fm_loopback_t *)(p + OAM_CELLTYPE_FUNCTYPE_LEN);
412         ND_PRINT((ndo, "\n\tLoopback-Indicator %s, Correlation-Tag 0x%08x",
413                tok2str(oam_fm_loopback_indicator_values,
414                        "Unknown",
415                        oam_ptr.oam_fm_loopback->loopback_indicator & OAM_FM_LOOPBACK_INDICATOR_MASK),
416                EXTRACT_32BITS(&oam_ptr.oam_fm_loopback->correlation_tag)));
417         ND_PRINT((ndo, "\n\tLocation-ID "));
418         for (idx = 0; idx < sizeof(oam_ptr.oam_fm_loopback->loopback_id); idx++) {
419             if (idx % 2) {
420                 ND_PRINT((ndo, "%04x ", EXTRACT_16BITS(&oam_ptr.oam_fm_loopback->loopback_id[idx])));
421             }
422         }
423         ND_PRINT((ndo, "\n\tSource-ID   "));
424         for (idx = 0; idx < sizeof(oam_ptr.oam_fm_loopback->source_id); idx++) {
425             if (idx % 2) {
426                 ND_PRINT((ndo, "%04x ", EXTRACT_16BITS(&oam_ptr.oam_fm_loopback->source_id[idx])));
427             }
428         }
429         break;
430 
431     case (OAM_CELLTYPE_FM << 4 | OAM_FM_FUNCTYPE_AIS):
432     case (OAM_CELLTYPE_FM << 4 | OAM_FM_FUNCTYPE_RDI):
433         oam_ptr.oam_fm_ais_rdi = (const struct oam_fm_ais_rdi_t *)(p + OAM_CELLTYPE_FUNCTYPE_LEN);
434         ND_PRINT((ndo, "\n\tFailure-type 0x%02x", oam_ptr.oam_fm_ais_rdi->failure_type));
435         ND_PRINT((ndo, "\n\tLocation-ID "));
436         for (idx = 0; idx < sizeof(oam_ptr.oam_fm_ais_rdi->failure_location); idx++) {
437             if (idx % 2) {
438                 ND_PRINT((ndo, "%04x ", EXTRACT_16BITS(&oam_ptr.oam_fm_ais_rdi->failure_location[idx])));
439             }
440         }
441         break;
442 
443     case (OAM_CELLTYPE_FM << 4 | OAM_FM_FUNCTYPE_CONTCHECK):
444         /* FIXME */
445         break;
446 
447     default:
448         break;
449     }
450 
451     /* crc10 checksum verification */
452     cksum = EXTRACT_16BITS(p + OAM_CELLTYPE_FUNCTYPE_LEN + OAM_FUNCTION_SPECIFIC_LEN)
453         & OAM_CRC10_MASK;
454     cksum_shouldbe = verify_crc10_cksum(0, p, OAM_PAYLOAD_LEN);
455 
456     ND_PRINT((ndo, "\n\tcksum 0x%03x (%scorrect)",
457            cksum,
458            cksum_shouldbe == 0 ? "" : "in"));
459 
460     return 1;
461 }
462