1/*
2 * Copyright 2009 Bert Vermeulen <bert@biot.com>
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that: (1) source code distributions
6 * retain the above copyright notice and this paragraph in its entirety, (2)
7 * distributions including binary code include the above copyright notice and
8 * this paragraph in its entirety in the documentation or other materials
9 * provided with the distribution, and (3) all advertising materials mentioning
10 * features or use of this software display the following acknowledgement:
11 * ``This product includes software developed by Paolo Abeni.''
12 * The name of author may not be used to endorse or promote products derived
13 * from this software without specific prior written permission.
14 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
15 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
16 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
17 *
18 * Support for USB packets
19 *
20 */
21
22/* \summary: USB printer */
23
24#ifdef HAVE_CONFIG_H
25#include <config.h>
26#endif
27
28#include "netdissect-stdinc.h"
29
30#define ND_LONGJMP_FROM_TCHECK
31#include "netdissect.h"
32#include "extract.h"
33
34#ifdef DLT_USB_LINUX
35/*
36 * possible transfer mode
37 */
38#define URB_TRANSFER_IN   0x80
39#define URB_ISOCHRONOUS   0x0
40#define URB_INTERRUPT     0x1
41#define URB_CONTROL       0x2
42#define URB_BULK          0x3
43
44/*
45 * possible event type
46 */
47#define URB_SUBMIT        'S'
48#define URB_COMPLETE      'C'
49#define URB_ERROR         'E'
50
51/*
52 * USB setup header as defined in USB specification.
53 * Appears at the front of each Control S-type packet in DLT_USB captures.
54 */
55typedef struct _usb_setup {
56	nd_uint8_t bmRequestType;
57	nd_uint8_t bRequest;
58	nd_uint16_t wValue;
59	nd_uint16_t wIndex;
60	nd_uint16_t wLength;
61} pcap_usb_setup;
62
63/*
64 * Information from the URB for Isochronous transfers.
65 */
66typedef struct _iso_rec {
67	nd_int32_t	error_count;
68	nd_int32_t	numdesc;
69} iso_rec;
70
71/*
72 * Header prepended by linux kernel to each event.
73 * Appears at the front of each packet in DLT_USB_LINUX captures.
74 */
75typedef struct _usb_header {
76	nd_uint64_t id;
77	nd_uint8_t event_type;
78	nd_uint8_t transfer_type;
79	nd_uint8_t endpoint_number;
80	nd_uint8_t device_address;
81	nd_uint16_t bus_id;
82	nd_uint8_t setup_flag;/*if !=0 the urb setup header is not present*/
83	nd_uint8_t data_flag; /*if !=0 no urb data is present*/
84	nd_int64_t ts_sec;
85	nd_int32_t ts_usec;
86	nd_int32_t status;
87	nd_uint32_t urb_len;
88	nd_uint32_t data_len; /* amount of urb data really present in this event*/
89	pcap_usb_setup setup;
90} pcap_usb_header;
91
92/*
93 * Header prepended by linux kernel to each event for the 2.6.31
94 * and later kernels; for the 2.6.21 through 2.6.30 kernels, the
95 * "iso_rec" information, and the fields starting with "interval"
96 * are zeroed-out padding fields.
97 *
98 * Appears at the front of each packet in DLT_USB_LINUX_MMAPPED captures.
99 */
100typedef struct _usb_header_mmapped {
101	nd_uint64_t id;
102	nd_uint8_t event_type;
103	nd_uint8_t transfer_type;
104	nd_uint8_t endpoint_number;
105	nd_uint8_t device_address;
106	nd_uint16_t bus_id;
107	nd_uint8_t setup_flag;/*if !=0 the urb setup header is not present*/
108	nd_uint8_t data_flag; /*if !=0 no urb data is present*/
109	nd_int64_t ts_sec;
110	nd_int32_t ts_usec;
111	nd_int32_t status;
112	nd_uint32_t urb_len;
113	nd_uint32_t data_len; /* amount of urb data really present in this event*/
114	union {
115		pcap_usb_setup setup;
116		iso_rec iso;
117	} s;
118	nd_int32_t interval;	/* for Interrupt and Isochronous events */
119	nd_int32_t start_frame;	/* for Isochronous events */
120	nd_uint32_t xfer_flags;	/* copy of URB's transfer flags */
121	nd_uint32_t ndesc;	/* number of isochronous descriptors */
122} pcap_usb_header_mmapped;
123
124/*
125 * Isochronous descriptors; for isochronous transfers there might be
126 * one or more of these at the beginning of the packet data.  The
127 * number of descriptors is given by the "ndesc" field in the header;
128 * as indicated, in older kernels that don't put the descriptors at
129 * the beginning of the packet, that field is zeroed out, so that field
130 * can be trusted even in captures from older kernels.
131 */
132typedef struct _usb_isodesc {
133	nd_int32_t	status;
134	nd_uint32_t	offset;
135	nd_uint32_t	len;
136	nd_byte		pad[4];
137} usb_isodesc;
138
139
140/* returns direction: 1=inbound 2=outbound -1=invalid */
141static int
142get_direction(int transfer_type, int event_type)
143{
144	int direction;
145
146	direction = -1;
147	switch(transfer_type){
148	case URB_BULK:
149	case URB_CONTROL:
150	case URB_ISOCHRONOUS:
151		switch(event_type)
152		{
153		case URB_SUBMIT:
154			direction = 2;
155			break;
156		case URB_COMPLETE:
157		case URB_ERROR:
158			direction = 1;
159			break;
160		default:
161			direction = -1;
162		}
163		break;
164	case URB_INTERRUPT:
165		switch(event_type)
166		{
167		case URB_SUBMIT:
168			direction = 1;
169			break;
170		case URB_COMPLETE:
171		case URB_ERROR:
172			direction = 2;
173			break;
174		default:
175			direction = -1;
176		}
177		break;
178	 default:
179		direction = -1;
180	}
181
182	return direction;
183}
184
185static void
186usb_header_print(netdissect_options *ndo, const pcap_usb_header *uh)
187{
188	int direction;
189	uint8_t transfer_type, event_type;
190
191	ndo->ndo_protocol = "usb";
192
193	nd_print_protocol_caps(ndo);
194	if (ndo->ndo_qflag)
195		return;
196
197	ND_PRINT(" ");
198	transfer_type = GET_U_1(uh->transfer_type);
199	switch(transfer_type)
200	{
201		case URB_ISOCHRONOUS:
202			ND_PRINT("ISOCHRONOUS");
203			break;
204		case URB_INTERRUPT:
205			ND_PRINT("INTERRUPT");
206			break;
207		case URB_CONTROL:
208			ND_PRINT("CONTROL");
209			break;
210		case URB_BULK:
211			ND_PRINT("BULK");
212			break;
213		default:
214			ND_PRINT(" ?");
215	}
216
217	event_type = GET_U_1(uh->event_type);
218	switch(event_type)
219	{
220		case URB_SUBMIT:
221			ND_PRINT(" SUBMIT");
222			break;
223		case URB_COMPLETE:
224			ND_PRINT(" COMPLETE");
225			break;
226		case URB_ERROR:
227			ND_PRINT(" ERROR");
228			break;
229		default:
230			ND_PRINT(" ?");
231	}
232
233	direction = get_direction(transfer_type, event_type);
234	if(direction == 1)
235		ND_PRINT(" from");
236	else if(direction == 2)
237		ND_PRINT(" to");
238	ND_PRINT(" %u:%u:%u", GET_HE_U_2(uh->bus_id),
239		 GET_U_1(uh->device_address),
240		 GET_U_1(uh->endpoint_number) & 0x7f);
241}
242
243/*
244 * This is the top level routine of the printer for captures with a
245 * 48-byte header.
246 *
247 * 'p' points to the header of the packet, 'h->ts' is the timestamp,
248 * 'h->len' is the length of the packet off the wire, and 'h->caplen'
249 * is the number of bytes actually captured.
250 */
251void
252usb_linux_48_byte_if_print(netdissect_options *ndo,
253                           const struct pcap_pkthdr *h _U_, const u_char *p)
254{
255	ndo->ndo_protocol = "usb_linux_48_byte";
256	ND_TCHECK_LEN(p, sizeof(pcap_usb_header));
257	ndo->ndo_ll_hdr_len += sizeof (pcap_usb_header);
258
259	usb_header_print(ndo, (const pcap_usb_header *) p);
260}
261
262#ifdef DLT_USB_LINUX_MMAPPED
263/*
264 * This is the top level routine of the printer for captures with a
265 * 64-byte header.
266 *
267 * 'p' points to the header of the packet, 'h->ts' is the timestamp,
268 * 'h->len' is the length of the packet off the wire, and 'h->caplen'
269 * is the number of bytes actually captured.
270 */
271void
272usb_linux_64_byte_if_print(netdissect_options *ndo,
273                           const struct pcap_pkthdr *h _U_, const u_char *p)
274{
275	ndo->ndo_protocol = "usb_linux_64_byte";
276	ND_TCHECK_LEN(p, sizeof(pcap_usb_header_mmapped));
277	ndo->ndo_ll_hdr_len += sizeof (pcap_usb_header_mmapped);
278
279	usb_header_print(ndo, (const pcap_usb_header *) p);
280}
281#endif /* DLT_USB_LINUX_MMAPPED */
282
283#endif /* DLT_USB_LINUX */
284
285