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  * Original code by Hannes Gredler (hannes@gredler.at)
16  */
17 
18 /* \summary: IEEE 802.3ah Multi-Point Control Protocol (MPCP) 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 
29 struct mpcp_common_header_t {
30     nd_uint16_t opcode;
31     nd_uint32_t timestamp;
32 };
33 
34 #define	MPCP_OPCODE_PAUSE   0x0001
35 #define	MPCP_OPCODE_GATE    0x0002
36 #define	MPCP_OPCODE_REPORT  0x0003
37 #define	MPCP_OPCODE_REG_REQ 0x0004
38 #define	MPCP_OPCODE_REG     0x0005
39 #define	MPCP_OPCODE_REG_ACK 0x0006
40 
41 static const struct tok mpcp_opcode_values[] = {
42     { MPCP_OPCODE_PAUSE, "Pause" },
43     { MPCP_OPCODE_GATE, "Gate" },
44     { MPCP_OPCODE_REPORT, "Report" },
45     { MPCP_OPCODE_REG_REQ, "Register Request" },
46     { MPCP_OPCODE_REG, "Register" },
47     { MPCP_OPCODE_REG_ACK, "Register ACK" },
48     { 0, NULL}
49 };
50 
51 #define MPCP_GRANT_NUMBER_LEN 1
52 #define	MPCP_GRANT_NUMBER_MASK 0x7
53 static const struct tok mpcp_grant_flag_values[] = {
54     { 0x08, "Discovery" },
55     { 0x10, "Force Grant #1" },
56     { 0x20, "Force Grant #2" },
57     { 0x40, "Force Grant #3" },
58     { 0x80, "Force Grant #4" },
59     { 0, NULL}
60 };
61 
62 struct mpcp_grant_t {
63     nd_uint32_t starttime;
64     nd_uint16_t duration;
65 };
66 
67 struct mpcp_reg_req_t {
68     nd_uint8_t flags;
69     nd_uint8_t pending_grants;
70 };
71 
72 
73 static const struct tok mpcp_reg_req_flag_values[] = {
74     { 1, "Register" },
75     { 3, "De-Register" },
76     { 0, NULL}
77 };
78 
79 struct mpcp_reg_t {
80     nd_uint16_t assigned_port;
81     nd_uint8_t  flags;
82     nd_uint16_t sync_time;
83     nd_uint8_t  echoed_pending_grants;
84 };
85 
86 static const struct tok mpcp_reg_flag_values[] = {
87     { 1, "Re-Register" },
88     { 2, "De-Register" },
89     { 3, "ACK" },
90     { 4, "NACK" },
91     { 0, NULL}
92 };
93 
94 #define MPCP_REPORT_QUEUESETS_LEN    1
95 #define MPCP_REPORT_REPORTBITMAP_LEN 1
96 static const struct tok mpcp_report_bitmap_values[] = {
97     { 0x01, "Q0" },
98     { 0x02, "Q1" },
99     { 0x04, "Q2" },
100     { 0x08, "Q3" },
101     { 0x10, "Q4" },
102     { 0x20, "Q5" },
103     { 0x40, "Q6" },
104     { 0x80, "Q7" },
105     { 0, NULL}
106 };
107 
108 struct mpcp_reg_ack_t {
109     nd_uint8_t  flags;
110     nd_uint16_t echoed_assigned_port;
111     nd_uint16_t echoed_sync_time;
112 };
113 
114 static const struct tok mpcp_reg_ack_flag_values[] = {
115     { 0, "NACK" },
116     { 1, "ACK" },
117     { 0, NULL}
118 };
119 
120 void
mpcp_print(netdissect_options * ndo,const u_char * pptr,u_int length)121 mpcp_print(netdissect_options *ndo, const u_char *pptr, u_int length)
122 {
123     const struct mpcp_common_header_t *mpcp_common_header;
124     const struct mpcp_reg_req_t *mpcp_reg_req;
125     const struct mpcp_reg_t *mpcp_reg;
126     const struct mpcp_reg_ack_t *mpcp_reg_ack;
127 
128 
129     const u_char *tptr;
130     uint16_t opcode;
131     uint32_t timestamp;
132     uint8_t grant_numbers, grant;
133     uint8_t queue_sets, queue_set, report_bitmap, report;
134 
135     ndo->ndo_protocol = "mpcp";
136     tptr=pptr;
137     mpcp_common_header = (const struct mpcp_common_header_t *)pptr;
138 
139     opcode = GET_BE_U_2(mpcp_common_header->opcode);
140     timestamp = GET_BE_U_4(mpcp_common_header->timestamp);
141     ND_PRINT("MPCP, Opcode %s", tok2str(mpcp_opcode_values, "Unknown (%u)", opcode));
142     if (opcode != MPCP_OPCODE_PAUSE) {
143         ND_PRINT(", Timestamp %u ticks", timestamp);
144     }
145     ND_PRINT(", length %u", length);
146 
147     if (!ndo->ndo_vflag)
148         return;
149 
150     tptr += sizeof(struct mpcp_common_header_t);
151 
152     switch (opcode) {
153     case MPCP_OPCODE_PAUSE:
154         break;
155 
156     case MPCP_OPCODE_GATE:
157         grant_numbers = GET_U_1(tptr) & MPCP_GRANT_NUMBER_MASK;
158         ND_PRINT("\n\tGrant Numbers %u, Flags [ %s ]",
159                grant_numbers,
160                bittok2str(mpcp_grant_flag_values,
161                           "?",
162                           GET_U_1(tptr) & ~MPCP_GRANT_NUMBER_MASK));
163         tptr++;
164 
165         for (grant = 1; grant <= grant_numbers; grant++) {
166             const struct mpcp_grant_t *mpcp_grant = (const struct mpcp_grant_t *)tptr;
167             ND_PRINT("\n\tGrant #%u, Start-Time %u ticks, duration %u ticks",
168                    grant,
169                    GET_BE_U_4(mpcp_grant->starttime),
170                    GET_BE_U_2(mpcp_grant->duration));
171             tptr += sizeof(struct mpcp_grant_t);
172         }
173 
174         ND_PRINT("\n\tSync-Time %u ticks", GET_BE_U_2(tptr));
175         break;
176 
177 
178     case MPCP_OPCODE_REPORT:
179         queue_sets = GET_U_1(tptr);
180         tptr+=MPCP_REPORT_QUEUESETS_LEN;
181         ND_PRINT("\n\tTotal Queue-Sets %u", queue_sets);
182 
183         for (queue_set = 1; queue_set < queue_sets; queue_set++) {
184             report_bitmap = GET_U_1(tptr);
185             ND_PRINT("\n\t  Queue-Set #%u, Report-Bitmap [ %s ]",
186                    queue_sets,
187                    bittok2str(mpcp_report_bitmap_values, "Unknown", report_bitmap));
188             tptr++;
189 
190             report=1;
191             while (report_bitmap != 0) {
192                 if (report_bitmap & 1) {
193                     ND_PRINT("\n\t    Q%u Report, Duration %u ticks",
194                            report,
195                            GET_BE_U_2(tptr));
196                     tptr += 2;
197                 }
198                 report++;
199                 report_bitmap = report_bitmap >> 1;
200             }
201         }
202         break;
203 
204     case MPCP_OPCODE_REG_REQ:
205         mpcp_reg_req = (const struct mpcp_reg_req_t *)tptr;
206         ND_PRINT("\n\tFlags [ %s ], Pending-Grants %u",
207                bittok2str(mpcp_reg_req_flag_values, "Reserved", GET_U_1(mpcp_reg_req->flags)),
208                GET_U_1(mpcp_reg_req->pending_grants));
209         break;
210 
211     case MPCP_OPCODE_REG:
212         mpcp_reg = (const struct mpcp_reg_t *)tptr;
213         ND_PRINT("\n\tAssigned-Port %u, Flags [ %s ]"
214                "\n\tSync-Time %u ticks, Echoed-Pending-Grants %u",
215                GET_BE_U_2(mpcp_reg->assigned_port),
216                bittok2str(mpcp_reg_flag_values, "Reserved", GET_U_1(mpcp_reg->flags)),
217                GET_BE_U_2(mpcp_reg->sync_time),
218                GET_U_1(mpcp_reg->echoed_pending_grants));
219         break;
220 
221     case MPCP_OPCODE_REG_ACK:
222         mpcp_reg_ack = (const struct mpcp_reg_ack_t *)tptr;
223         ND_PRINT("\n\tEchoed-Assigned-Port %u, Flags [ %s ]"
224                "\n\tEchoed-Sync-Time %u ticks",
225                GET_BE_U_2(mpcp_reg_ack->echoed_assigned_port),
226                bittok2str(mpcp_reg_ack_flag_values, "Reserved", GET_U_1(mpcp_reg_ack->flags)),
227                GET_BE_U_2(mpcp_reg_ack->echoed_sync_time));
228         break;
229 
230     default:
231         /* unknown opcode - hexdump for now */
232         print_unknown_data(ndo,pptr, "\n\t", length);
233         break;
234     }
235 }
236