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 MPCP protocol as per 802.3ah
16  *
17  * Original code by Hannes Gredler (hannes@juniper.net)
18  */
19 
20 #define NETDISSECT_REWORKED
21 #ifdef HAVE_CONFIG_H
22 #include "config.h"
23 #endif
24 
25 #include <tcpdump-stdinc.h>
26 
27 #include "interface.h"
28 #include "extract.h"
29 
30 #define MPCP_TIMESTAMP_LEN        4
31 #define MPCP_TIMESTAMP_DURATION_LEN 2
32 
33 struct mpcp_common_header_t {
34     uint8_t opcode[2];
35     uint8_t timestamp[MPCP_TIMESTAMP_LEN];
36 };
37 
38 #define	MPCP_OPCODE_PAUSE   0x0001
39 #define	MPCP_OPCODE_GATE    0x0002
40 #define	MPCP_OPCODE_REPORT  0x0003
41 #define	MPCP_OPCODE_REG_REQ 0x0004
42 #define	MPCP_OPCODE_REG     0x0005
43 #define	MPCP_OPCODE_REG_ACK 0x0006
44 
45 static const struct tok mpcp_opcode_values[] = {
46     { MPCP_OPCODE_PAUSE, "Pause" },
47     { MPCP_OPCODE_GATE, "Gate" },
48     { MPCP_OPCODE_REPORT, "Report" },
49     { MPCP_OPCODE_REG_REQ, "Register Request" },
50     { MPCP_OPCODE_REG, "Register" },
51     { MPCP_OPCODE_REG_ACK, "Register ACK" },
52     { 0, NULL}
53 };
54 
55 #define MPCP_GRANT_NUMBER_LEN 1
56 #define	MPCP_GRANT_NUMBER_MASK 0x7
57 static const struct tok mpcp_grant_flag_values[] = {
58     { 0x08, "Discovery" },
59     { 0x10, "Force Grant #1" },
60     { 0x20, "Force Grant #2" },
61     { 0x40, "Force Grant #3" },
62     { 0x80, "Force Grant #4" },
63     { 0, NULL}
64 };
65 
66 struct mpcp_grant_t {
67     uint8_t starttime[MPCP_TIMESTAMP_LEN];
68     uint8_t duration[MPCP_TIMESTAMP_DURATION_LEN];
69 };
70 
71 struct mpcp_reg_req_t {
72     uint8_t flags;
73     uint8_t pending_grants;
74 };
75 
76 
77 static const struct tok mpcp_reg_req_flag_values[] = {
78     { 1, "Register" },
79     { 3, "De-Register" },
80     { 0, NULL}
81 };
82 
83 struct mpcp_reg_t {
84     uint8_t assigned_port[2];
85     uint8_t flags;
86     uint8_t sync_time[MPCP_TIMESTAMP_DURATION_LEN];
87     uint8_t echoed_pending_grants;
88 };
89 
90 static const struct tok mpcp_reg_flag_values[] = {
91     { 1, "Re-Register" },
92     { 2, "De-Register" },
93     { 3, "ACK" },
94     { 4, "NACK" },
95     { 0, NULL}
96 };
97 
98 #define MPCP_REPORT_QUEUESETS_LEN    1
99 #define MPCP_REPORT_REPORTBITMAP_LEN 1
100 static const struct tok mpcp_report_bitmap_values[] = {
101     { 0x01, "Q0" },
102     { 0x02, "Q1" },
103     { 0x04, "Q2" },
104     { 0x08, "Q3" },
105     { 0x10, "Q4" },
106     { 0x20, "Q5" },
107     { 0x40, "Q6" },
108     { 0x80, "Q7" },
109     { 0, NULL}
110 };
111 
112 struct mpcp_reg_ack_t {
113     uint8_t flags;
114     uint8_t echoed_assigned_port[2];
115     uint8_t echoed_sync_time[MPCP_TIMESTAMP_DURATION_LEN];
116 };
117 
118 static const struct tok mpcp_reg_ack_flag_values[] = {
119     { 0, "NACK" },
120     { 1, "ACK" },
121     { 0, NULL}
122 };
123 
124 void
mpcp_print(netdissect_options * ndo,register const u_char * pptr,register u_int length)125 mpcp_print(netdissect_options *ndo, register const u_char *pptr, register u_int length)
126 {
127     union {
128         const struct mpcp_common_header_t *common_header;
129         const struct mpcp_grant_t *grant;
130         const struct mpcp_reg_req_t *reg_req;
131         const struct mpcp_reg_t *reg;
132         const struct mpcp_reg_ack_t *reg_ack;
133     } mpcp;
134 
135 
136     const u_char *tptr;
137     uint16_t opcode;
138     uint8_t grant_numbers, grant;
139     uint8_t queue_sets, queue_set, report_bitmap, report;
140 
141     tptr=pptr;
142     mpcp.common_header = (const struct mpcp_common_header_t *)pptr;
143 
144     ND_TCHECK2(*tptr, sizeof(const struct mpcp_common_header_t));
145     opcode = EXTRACT_16BITS(mpcp.common_header->opcode);
146     ND_PRINT((ndo, "MPCP, Opcode %s", tok2str(mpcp_opcode_values, "Unknown (%u)", opcode)));
147     if (opcode != MPCP_OPCODE_PAUSE) {
148         ND_PRINT((ndo, ", Timestamp %u ticks", EXTRACT_32BITS(mpcp.common_header->timestamp)));
149     }
150     ND_PRINT((ndo, ", length %u", length));
151 
152     if (!ndo->ndo_vflag)
153         return;
154 
155     tptr += sizeof(const struct mpcp_common_header_t);
156 
157     switch (opcode) {
158     case MPCP_OPCODE_PAUSE:
159         break;
160 
161     case MPCP_OPCODE_GATE:
162         ND_TCHECK2(*tptr, MPCP_GRANT_NUMBER_LEN);
163         grant_numbers = *tptr & MPCP_GRANT_NUMBER_MASK;
164         ND_PRINT((ndo, "\n\tGrant Numbers %u, Flags [ %s ]",
165                grant_numbers,
166                bittok2str(mpcp_grant_flag_values,
167                           "?",
168                           *tptr &~ MPCP_GRANT_NUMBER_MASK)));
169         tptr++;
170 
171         for (grant = 1; grant <= grant_numbers; grant++) {
172             ND_TCHECK2(*tptr, sizeof(const struct mpcp_grant_t));
173             mpcp.grant = (const struct mpcp_grant_t *)tptr;
174             ND_PRINT((ndo, "\n\tGrant #%u, Start-Time %u ticks, duration %u ticks",
175                    grant,
176                    EXTRACT_32BITS(mpcp.grant->starttime),
177                    EXTRACT_16BITS(mpcp.grant->duration)));
178             tptr += sizeof(const struct mpcp_grant_t);
179         }
180 
181         ND_TCHECK2(*tptr, MPCP_TIMESTAMP_DURATION_LEN);
182         ND_PRINT((ndo, "\n\tSync-Time %u ticks", EXTRACT_16BITS(tptr)));
183         break;
184 
185 
186     case MPCP_OPCODE_REPORT:
187         ND_TCHECK2(*tptr, MPCP_REPORT_QUEUESETS_LEN);
188         queue_sets = *tptr;
189         tptr+=MPCP_REPORT_QUEUESETS_LEN;
190         ND_PRINT((ndo, "\n\tTotal Queue-Sets %u", queue_sets));
191 
192         for (queue_set = 1; queue_set < queue_sets; queue_set++) {
193             ND_TCHECK2(*tptr, MPCP_REPORT_REPORTBITMAP_LEN);
194             report_bitmap = *(tptr);
195             ND_PRINT((ndo, "\n\t  Queue-Set #%u, Report-Bitmap [ %s ]",
196                    queue_sets,
197                    bittok2str(mpcp_report_bitmap_values, "Unknown", report_bitmap)));
198             tptr++;
199 
200             report=1;
201             while (report_bitmap != 0) {
202                 if (report_bitmap & 1) {
203                     ND_TCHECK2(*tptr, MPCP_TIMESTAMP_DURATION_LEN);
204                     ND_PRINT((ndo, "\n\t    Q%u Report, Duration %u ticks",
205                            report,
206                            EXTRACT_16BITS(tptr)));
207                     tptr+=MPCP_TIMESTAMP_DURATION_LEN;
208                 }
209                 report++;
210                 report_bitmap = report_bitmap >> 1;
211             }
212         }
213         break;
214 
215     case MPCP_OPCODE_REG_REQ:
216         ND_TCHECK2(*tptr, sizeof(const struct mpcp_reg_req_t));
217         mpcp.reg_req = (const struct mpcp_reg_req_t *)tptr;
218         ND_PRINT((ndo, "\n\tFlags [ %s ], Pending-Grants %u",
219                bittok2str(mpcp_reg_req_flag_values, "Reserved", mpcp.reg_req->flags),
220                mpcp.reg_req->pending_grants));
221         break;
222 
223     case MPCP_OPCODE_REG:
224         ND_TCHECK2(*tptr, sizeof(const struct mpcp_reg_t));
225         mpcp.reg = (const struct mpcp_reg_t *)tptr;
226         ND_PRINT((ndo, "\n\tAssigned-Port %u, Flags [ %s ]" \
227                "\n\tSync-Time %u ticks, Echoed-Pending-Grants %u",
228                EXTRACT_16BITS(mpcp.reg->assigned_port),
229                bittok2str(mpcp_reg_flag_values, "Reserved", mpcp.reg->flags),
230                EXTRACT_16BITS(mpcp.reg->sync_time),
231                mpcp.reg->echoed_pending_grants));
232         break;
233 
234     case MPCP_OPCODE_REG_ACK:
235         ND_TCHECK2(*tptr, sizeof(const struct mpcp_reg_ack_t));
236         mpcp.reg_ack = (const struct mpcp_reg_ack_t *)tptr;
237         ND_PRINT((ndo, "\n\tEchoed-Assigned-Port %u, Flags [ %s ]" \
238                "\n\tEchoed-Sync-Time %u ticks",
239                EXTRACT_16BITS(mpcp.reg_ack->echoed_assigned_port),
240                bittok2str(mpcp_reg_ack_flag_values, "Reserved", mpcp.reg_ack->flags),
241                EXTRACT_16BITS(mpcp.reg_ack->echoed_sync_time)));
242         break;
243 
244     default:
245         /* unknown opcode - hexdump for now */
246         print_unknown_data(ndo,pptr, "\n\t", length);
247         break;
248     }
249 
250     return;
251 
252 trunc:
253     ND_PRINT((ndo, "\n\t[|MPCP]"));
254 }
255 /*
256  * Local Variables:
257  * c-style: whitesmith
258  * c-basic-offset: 8
259  * End:
260  */
261