xref: /freebsd/contrib/tcpdump/print-vqp.c (revision 9247238cc4b8835892a47701136b0fd073f8d67c)
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 Carles Kishimoto <Carles.Kishimoto@bsc.es>
16  */
17 
18 /* \summary: Cisco VLAN Query Protocol (VQP) printer */
19 
20 #ifdef HAVE_CONFIG_H
21 #include <config.h>
22 #endif
23 
24 #include "netdissect-stdinc.h"
25 
26 #define ND_LONGJMP_FROM_TCHECK
27 #include "netdissect.h"
28 #include "extract.h"
29 #include "addrtoname.h"
30 
31 #define VQP_VERSION 1
32 
33 /*
34  * VQP common header
35  *
36  *  0                   1                   2                   3
37  *  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
38  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
39  * |   Constant    | Packet type   |  Error Code   |    nitems     |
40  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
41  * |                Packet Sequence Number (4 bytes)               |
42  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
43  */
44 
45 struct vqp_common_header_t {
46     nd_uint8_t  version;
47     nd_uint8_t  msg_type;
48     nd_uint8_t  error_code;
49     nd_uint8_t  nitems;
50     nd_uint32_t sequence;
51 };
52 
53 struct vqp_obj_tlv_t {
54     nd_uint32_t obj_type;
55     nd_uint16_t obj_length;
56 };
57 
58 #define VQP_OBJ_REQ_JOIN_PORT  0x01
59 #define VQP_OBJ_RESP_VLAN      0x02
60 #define VQP_OBJ_REQ_RECONFIRM  0x03
61 #define VQP_OBJ_RESP_RECONFIRM 0x04
62 
63 static const struct tok vqp_msg_type_values[] = {
64     { VQP_OBJ_REQ_JOIN_PORT, "Request, Join Port"},
65     { VQP_OBJ_RESP_VLAN, "Response, VLAN"},
66     { VQP_OBJ_REQ_RECONFIRM, "Request, Reconfirm"},
67     { VQP_OBJ_RESP_RECONFIRM, "Response, Reconfirm"},
68     { 0, NULL}
69 };
70 
71 static const struct tok vqp_error_code_values[] = {
72     { 0x00, "No error"},
73     { 0x03, "Access denied"},
74     { 0x04, "Shutdown port"},
75     { 0x05, "Wrong VTP domain"},
76     { 0, NULL}
77 };
78 
79 /* FIXME the heading 0x0c looks ugly - those must be flags etc. */
80 #define VQP_OBJ_IP_ADDRESS    0x0c01
81 #define VQP_OBJ_PORT_NAME     0x0c02
82 #define VQP_OBJ_VLAN_NAME     0x0c03
83 #define VQP_OBJ_VTP_DOMAIN    0x0c04
84 #define VQP_OBJ_ETHERNET_PKT  0x0c05
85 #define VQP_OBJ_MAC_NULL      0x0c06
86 #define VQP_OBJ_MAC_ADDRESS   0x0c08
87 
88 static const struct tok vqp_obj_values[] = {
89     { VQP_OBJ_IP_ADDRESS, "Client IP Address" },
90     { VQP_OBJ_PORT_NAME, "Port Name" },
91     { VQP_OBJ_VLAN_NAME, "VLAN Name" },
92     { VQP_OBJ_VTP_DOMAIN, "VTP Domain" },
93     { VQP_OBJ_ETHERNET_PKT, "Ethernet Packet" },
94     { VQP_OBJ_MAC_NULL, "MAC Null" },
95     { VQP_OBJ_MAC_ADDRESS, "MAC Address" },
96     { 0, NULL}
97 };
98 
99 void
100 vqp_print(netdissect_options *ndo, const u_char *pptr, u_int len)
101 {
102     const struct vqp_common_header_t *vqp_common_header;
103     const struct vqp_obj_tlv_t *vqp_obj_tlv;
104 
105     const u_char *tptr;
106     uint8_t version;
107     uint16_t vqp_obj_len;
108     uint32_t vqp_obj_type;
109     u_int tlen;
110     uint8_t nitems;
111 
112     ndo->ndo_protocol = "vqp";
113     tptr=pptr;
114     tlen = len;
115     vqp_common_header = (const struct vqp_common_header_t *)pptr;
116     ND_TCHECK_SIZE(vqp_common_header);
117     if (sizeof(struct vqp_common_header_t) > tlen)
118         goto invalid;
119     version = GET_U_1(vqp_common_header->version);
120 
121     /*
122      * Sanity checking of the header.
123      */
124     if (version != VQP_VERSION) {
125 	ND_PRINT("VQP version %u packet not supported",
126                version);
127 	return;
128     }
129 
130     /* in non-verbose mode just lets print the basic Message Type */
131     if (ndo->ndo_vflag < 1) {
132         ND_PRINT("VQPv%u %s Message, error-code %s (%u), length %u",
133                version,
134                tok2str(vqp_msg_type_values, "unknown (%u)",GET_U_1(vqp_common_header->msg_type)),
135                tok2str(vqp_error_code_values, "unknown", GET_U_1(vqp_common_header->error_code)),
136                GET_U_1(vqp_common_header->error_code),
137                len);
138         return;
139     }
140 
141     /* ok they seem to want to know everything - lets fully decode it */
142     nitems = GET_U_1(vqp_common_header->nitems);
143     ND_PRINT("\n\tVQPv%u, %s Message, error-code %s (%u), seq 0x%08x, items %u, length %u",
144            version,
145 	   tok2str(vqp_msg_type_values, "unknown (%u)",GET_U_1(vqp_common_header->msg_type)),
146 	   tok2str(vqp_error_code_values, "unknown", GET_U_1(vqp_common_header->error_code)),
147 	   GET_U_1(vqp_common_header->error_code),
148 	   GET_BE_U_4(vqp_common_header->sequence),
149 	   nitems,
150            len);
151 
152     /* skip VQP Common header */
153     tptr+=sizeof(struct vqp_common_header_t);
154     tlen-=sizeof(struct vqp_common_header_t);
155 
156     while (nitems != 0 && tlen != 0) {
157 
158         vqp_obj_tlv = (const struct vqp_obj_tlv_t *)tptr;
159         ND_TCHECK_SIZE(vqp_obj_tlv);
160         if (sizeof(struct vqp_obj_tlv_t) > tlen)
161             goto invalid;
162         vqp_obj_type = GET_BE_U_4(vqp_obj_tlv->obj_type);
163         vqp_obj_len = GET_BE_U_2(vqp_obj_tlv->obj_length);
164         tptr+=sizeof(struct vqp_obj_tlv_t);
165         tlen-=sizeof(struct vqp_obj_tlv_t);
166 
167         ND_PRINT("\n\t  %s Object (0x%08x), length %u, value: ",
168                tok2str(vqp_obj_values, "Unknown", vqp_obj_type),
169                vqp_obj_type, vqp_obj_len);
170 
171         /* basic sanity check */
172         if (vqp_obj_type == 0 || vqp_obj_len ==0) {
173             return;
174         }
175 
176         /* did we capture enough for fully decoding the object ? */
177         ND_TCHECK_LEN(tptr, vqp_obj_len);
178         if (vqp_obj_len > tlen)
179             goto invalid;
180 
181         switch(vqp_obj_type) {
182 	case VQP_OBJ_IP_ADDRESS:
183             if (vqp_obj_len != 4)
184                 goto invalid;
185             ND_PRINT("%s (0x%08x)", GET_IPADDR_STRING(tptr),
186                      GET_BE_U_4(tptr));
187             break;
188             /* those objects have similar semantics - fall through */
189         case VQP_OBJ_PORT_NAME:
190 	case VQP_OBJ_VLAN_NAME:
191 	case VQP_OBJ_VTP_DOMAIN:
192 	case VQP_OBJ_ETHERNET_PKT:
193             nd_printjnp(ndo, tptr, vqp_obj_len);
194             break;
195             /* those objects have similar semantics - fall through */
196 	case VQP_OBJ_MAC_ADDRESS:
197 	case VQP_OBJ_MAC_NULL:
198             if (vqp_obj_len != MAC_ADDR_LEN)
199                 goto invalid;
200 	      ND_PRINT("%s", GET_ETHERADDR_STRING(tptr));
201               break;
202         default:
203             if (ndo->ndo_vflag <= 1)
204                 print_unknown_data(ndo,tptr, "\n\t    ", vqp_obj_len);
205             break;
206         }
207 	tptr += vqp_obj_len;
208 	tlen -= vqp_obj_len;
209 	nitems--;
210     }
211     return;
212 invalid:
213     nd_print_invalid(ndo);
214 }
215