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 #include <sys/cdefs.h>
23 #ifndef lint
24 __RCSID("$NetBSD: print-usb.c,v 1.5 2024/09/02 16:15:33 christos Exp $");
25 #endif
26 
27 /* \summary: USB printer */
28 
29 #include <config.h>
30 
31 #include "netdissect-stdinc.h"
32 
33 #define ND_LONGJMP_FROM_TCHECK
34 #include "netdissect.h"
35 #include "extract.h"
36 
37 #ifdef DLT_USB_LINUX
38 /*
39  * possible transfer mode
40  */
41 #define URB_TRANSFER_IN   0x80
42 #define URB_ISOCHRONOUS   0x0
43 #define URB_INTERRUPT     0x1
44 #define URB_CONTROL       0x2
45 #define URB_BULK          0x3
46 
47 /*
48  * possible event type
49  */
50 #define URB_SUBMIT        'S'
51 #define URB_COMPLETE      'C'
52 #define URB_ERROR         'E'
53 
54 /*
55  * USB setup header as defined in USB specification.
56  * Appears at the front of each Control S-type packet in DLT_USB captures.
57  */
58 typedef struct _usb_setup {
59           nd_uint8_t bmRequestType;
60           nd_uint8_t bRequest;
61           nd_uint16_t wValue;
62           nd_uint16_t wIndex;
63           nd_uint16_t wLength;
64 } pcap_usb_setup;
65 
66 /*
67  * Information from the URB for Isochronous transfers.
68  */
69 typedef struct _iso_rec {
70           nd_int32_t          error_count;
71           nd_int32_t          numdesc;
72 } iso_rec;
73 
74 /*
75  * Header prepended by linux kernel to each event.
76  * Appears at the front of each packet in DLT_USB_LINUX captures.
77  */
78 typedef struct _usb_header {
79           nd_uint64_t id;
80           nd_uint8_t event_type;
81           nd_uint8_t transfer_type;
82           nd_uint8_t endpoint_number;
83           nd_uint8_t device_address;
84           nd_uint16_t bus_id;
85           nd_uint8_t setup_flag;/*if !=0 the urb setup header is not present*/
86           nd_uint8_t data_flag; /*if !=0 no urb data is present*/
87           nd_int64_t ts_sec;
88           nd_int32_t ts_usec;
89           nd_int32_t status;
90           nd_uint32_t urb_len;
91           nd_uint32_t data_len; /* amount of urb data really present in this event*/
92           pcap_usb_setup setup;
93 } pcap_usb_header;
94 
95 /*
96  * Header prepended by linux kernel to each event for the 2.6.31
97  * and later kernels; for the 2.6.21 through 2.6.30 kernels, the
98  * "iso_rec" information, and the fields starting with "interval"
99  * are zeroed-out padding fields.
100  *
101  * Appears at the front of each packet in DLT_USB_LINUX_MMAPPED captures.
102  */
103 typedef struct _usb_header_mmapped {
104           nd_uint64_t id;
105           nd_uint8_t event_type;
106           nd_uint8_t transfer_type;
107           nd_uint8_t endpoint_number;
108           nd_uint8_t device_address;
109           nd_uint16_t bus_id;
110           nd_uint8_t setup_flag;/*if !=0 the urb setup header is not present*/
111           nd_uint8_t data_flag; /*if !=0 no urb data is present*/
112           nd_int64_t ts_sec;
113           nd_int32_t ts_usec;
114           nd_int32_t status;
115           nd_uint32_t urb_len;
116           nd_uint32_t data_len; /* amount of urb data really present in this event*/
117           union {
118                     pcap_usb_setup setup;
119                     iso_rec iso;
120           } s;
121           nd_int32_t interval;          /* for Interrupt and Isochronous events */
122           nd_int32_t start_frame;       /* for Isochronous events */
123           nd_uint32_t xfer_flags;       /* copy of URB's transfer flags */
124           nd_uint32_t ndesc;  /* number of isochronous descriptors */
125 } pcap_usb_header_mmapped;
126 
127 /*
128  * Isochronous descriptors; for isochronous transfers there might be
129  * one or more of these at the beginning of the packet data.  The
130  * number of descriptors is given by the "ndesc" field in the header;
131  * as indicated, in older kernels that don't put the descriptors at
132  * the beginning of the packet, that field is zeroed out, so that field
133  * can be trusted even in captures from older kernels.
134  */
135 typedef struct _usb_isodesc {
136           nd_int32_t          status;
137           nd_uint32_t         offset;
138           nd_uint32_t         len;
139           nd_byte             pad[4];
140 } usb_isodesc;
141 
142 
143 /* returns direction: 1=inbound 2=outbound -1=invalid */
144 static int
get_direction(int transfer_type,int event_type)145 get_direction(int transfer_type, int event_type)
146 {
147           int direction;
148 
149           direction = -1;
150           switch(transfer_type){
151           case URB_BULK:
152           case URB_CONTROL:
153           case URB_ISOCHRONOUS:
154                     switch(event_type) {
155                     case URB_SUBMIT:
156                               direction = 2;
157                               break;
158                     case URB_COMPLETE:
159                     case URB_ERROR:
160                               direction = 1;
161                               break;
162                     default:
163                               direction = -1;
164                     }
165                     break;
166           case URB_INTERRUPT:
167                     switch(event_type) {
168                     case URB_SUBMIT:
169                               direction = 1;
170                               break;
171                     case URB_COMPLETE:
172                     case URB_ERROR:
173                               direction = 2;
174                               break;
175                     default:
176                               direction = -1;
177                     }
178                     break;
179            default:
180                     direction = -1;
181           }
182 
183           return direction;
184 }
185 
186 static void
usb_header_print(netdissect_options * ndo,const pcap_usb_header * uh)187 usb_header_print(netdissect_options *ndo, const pcap_usb_header *uh)
188 {
189           int direction;
190           uint8_t transfer_type, event_type;
191 
192           ndo->ndo_protocol = "usb";
193 
194           nd_print_protocol_caps(ndo);
195           if (ndo->ndo_qflag)
196                     return;
197 
198           ND_PRINT(" ");
199           transfer_type = GET_U_1(uh->transfer_type);
200           switch(transfer_type) {
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                     case URB_SUBMIT:
220                               ND_PRINT(" SUBMIT");
221                               break;
222                     case URB_COMPLETE:
223                               ND_PRINT(" COMPLETE");
224                               break;
225                     case URB_ERROR:
226                               ND_PRINT(" ERROR");
227                               break;
228                     default:
229                               ND_PRINT(" ?");
230           }
231 
232           direction = get_direction(transfer_type, event_type);
233           if(direction == 1)
234                     ND_PRINT(" from");
235           else if(direction == 2)
236                     ND_PRINT(" to");
237           ND_PRINT(" %u:%u:%u", GET_HE_U_2(uh->bus_id),
238                      GET_U_1(uh->device_address),
239                      GET_U_1(uh->endpoint_number) & 0x7f);
240 }
241 
242 /*
243  * This is the top level routine of the printer for captures with a
244  * 48-byte header.
245  *
246  * 'p' points to the header of the packet, 'h->ts' is the timestamp,
247  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
248  * is the number of bytes actually captured.
249  */
250 void
usb_linux_48_byte_if_print(netdissect_options * ndo,const struct pcap_pkthdr * h _U_,const u_char * p)251 usb_linux_48_byte_if_print(netdissect_options *ndo,
252                            const struct pcap_pkthdr *h _U_, const u_char *p)
253 {
254           ndo->ndo_protocol = "usb_linux_48_byte";
255           ND_TCHECK_LEN(p, sizeof(pcap_usb_header));
256           ndo->ndo_ll_hdr_len += sizeof (pcap_usb_header);
257 
258           usb_header_print(ndo, (const pcap_usb_header *) p);
259 }
260 
261 #ifdef DLT_USB_LINUX_MMAPPED
262 /*
263  * This is the top level routine of the printer for captures with a
264  * 64-byte header.
265  *
266  * 'p' points to the header of the packet, 'h->ts' is the timestamp,
267  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
268  * is the number of bytes actually captured.
269  */
270 void
usb_linux_64_byte_if_print(netdissect_options * ndo,const struct pcap_pkthdr * h _U_,const u_char * p)271 usb_linux_64_byte_if_print(netdissect_options *ndo,
272                            const struct pcap_pkthdr *h _U_, const u_char *p)
273 {
274           ndo->ndo_protocol = "usb_linux_64_byte";
275           ND_TCHECK_LEN(p, sizeof(pcap_usb_header_mmapped));
276           ndo->ndo_ll_hdr_len += sizeof (pcap_usb_header_mmapped);
277 
278           usb_header_print(ndo, (const pcap_usb_header *) p);
279 }
280 #endif /* DLT_USB_LINUX_MMAPPED */
281 
282 #endif /* DLT_USB_LINUX */
283 
284