The Tcpdump Group git mirrors - tcpdump/blob - print-usb.c

   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 #include "netdissect.h"
  31 #include "extract.h"
  32
  33 #ifdef DLT_USB_LINUX
  34 /*
  35  * possible transfer mode
  36  */
  37 #define URB_TRANSFER_IN   0x80
  38 #define URB_ISOCHRONOUS   0x0
  39 #define URB_INTERRUPT     0x1
  40 #define URB_CONTROL       0x2
  41 #define URB_BULK          0x3
  42
  43 /*
  44  * possible event type
  45  */
  46 #define URB_SUBMIT        'S'
  47 #define URB_COMPLETE      'C'
  48 #define URB_ERROR         'E'
  49
  50 /*
  51  * USB setup header as defined in USB specification.
  52  * Appears at the front of each Control S-type packet in DLT_USB captures.
  53  */
  54 typedef struct _usb_setup {
  55         nd_uint8_t bmRequestType;
  56         nd_uint8_t bRequest;
  57         nd_uint16_t wValue;
  58         nd_uint16_t wIndex;
  59         nd_uint16_t wLength;
  60 } pcap_usb_setup;
  61
  62 /*
  63  * Information from the URB for Isochronous transfers.
  64  */
  65 typedef struct _iso_rec {
  66         nd_int32_t      error_count;
  67         nd_int32_t      numdesc;
  68 } iso_rec;
  69
  70 /*
  71  * Header prepended by linux kernel to each event.
  72  * Appears at the front of each packet in DLT_USB_LINUX captures.
  73  */
  74 typedef struct _usb_header {
  75         nd_uint64_t id;
  76         nd_uint8_t event_type;
  77         nd_uint8_t transfer_type;
  78         nd_uint8_t endpoint_number;
  79         nd_uint8_t device_address;
  80         nd_uint16_t bus_id;
  81         nd_uint8_t setup_flag;/*if !=0 the urb setup header is not present*/
  82         nd_uint8_t data_flag; /*if !=0 no urb data is present*/
  83         nd_int64_t ts_sec;
  84         nd_int32_t ts_usec;
  85         nd_int32_t status;
  86         nd_uint32_t urb_len;
  87         nd_uint32_t data_len; /* amount of urb data really present in this event*/
  88         pcap_usb_setup setup;
  89 } pcap_usb_header;
  90
  91 /*
  92  * Header prepended by linux kernel to each event for the 2.6.31
  93  * and later kernels; for the 2.6.21 through 2.6.30 kernels, the
  94  * "iso_rec" information, and the fields starting with "interval"
  95  * are zeroed-out padding fields.
  96  *
  97  * Appears at the front of each packet in DLT_USB_LINUX_MMAPPED captures.
  98  */
  99 typedef struct _usb_header_mmapped {
 100         nd_uint64_t id;
 101         nd_uint8_t event_type;
 102         nd_uint8_t transfer_type;
 103         nd_uint8_t endpoint_number;
 104         nd_uint8_t device_address;
 105         nd_uint16_t bus_id;
 106         nd_uint8_t setup_flag;/*if !=0 the urb setup header is not present*/
 107         nd_uint8_t data_flag; /*if !=0 no urb data is present*/
 108         nd_int64_t ts_sec;
 109         nd_int32_t ts_usec;
 110         nd_int32_t status;
 111         nd_uint32_t urb_len;
 112         nd_uint32_t data_len; /* amount of urb data really present in this event*/
 113         union {
 114                 pcap_usb_setup setup;
 115                 iso_rec iso;
 116         } s;
 117         nd_int32_t interval;    /* for Interrupt and Isochronous events */
 118         nd_int32_t start_frame; /* for Isochronous events */
 119         nd_uint32_t xfer_flags; /* copy of URB's transfer flags */
 120         nd_uint32_t ndesc;      /* number of isochronous descriptors */
 121 } pcap_usb_header_mmapped;
 122
 123 /*
 124  * Isochronous descriptors; for isochronous transfers there might be
 125  * one or more of these at the beginning of the packet data.  The
 126  * number of descriptors is given by the "ndesc" field in the header;
 127  * as indicated, in older kernels that don't put the descriptors at
 128  * the beginning of the packet, that field is zeroed out, so that field
 129  * can be trusted even in captures from older kernels.
 130  */
 131 typedef struct _usb_isodesc {
 132         nd_int32_t      status;
 133         nd_uint32_t     offset;
 134         nd_uint32_t     len;
 135         nd_byte         pad[4];
 136 } usb_isodesc;
 137
 138
 139 /* returns direction: 1=inbound 2=outbound -1=invalid */
 140 static int
 141 get_direction(int transfer_type, int event_type)
 142 {
 143         int direction;
 144
 145         direction = -1;
 146         switch(transfer_type){
 147         case URB_BULK:
 148         case URB_CONTROL:
 149         case URB_ISOCHRONOUS:
 150                 switch(event_type)
 151                 {
 152                 case URB_SUBMIT:
 153                         direction = 2;
 154                         break;
 155                 case URB_COMPLETE:
 156                 case URB_ERROR:
 157                         direction = 1;
 158                         break;
 159                 default:
 160                         direction = -1;
 161                 }
 162                 break;
 163         case URB_INTERRUPT:
 164                 switch(event_type)
 165                 {
 166                 case URB_SUBMIT:
 167                         direction = 1;
 168                         break;
 169                 case URB_COMPLETE:
 170                 case URB_ERROR:
 171                         direction = 2;
 172                         break;
 173                 default:
 174                         direction = -1;
 175                 }
 176                 break;
 177          default:
 178                 direction = -1;
 179         }
 180
 181         return direction;
 182 }
 183
 184 static void
 185 usb_header_print(netdissect_options *ndo, const pcap_usb_header *uh)
 186 {
 187         int direction;
 188         uint8_t transfer_type, event_type;
 189
 190         ndo->ndo_protocol = "usb";
 191
 192         nd_print_protocol_caps(ndo);
 193         if (ndo->ndo_qflag)
 194                 return;
 195
 196         ND_PRINT(" ");
 197         transfer_type = GET_U_1(uh->transfer_type);
 198         switch(transfer_type)
 199         {
 200                 case URB_ISOCHRONOUS:
 201                         ND_PRINT("ISOCHRONOUS");
 202                         break;
 203                 case URB_INTERRUPT:
 204                         ND_PRINT("INTERRUPT");
 205                         break;
 206                 case URB_CONTROL:
 207                         ND_PRINT("CONTROL");
 208                         break;
 209                 case URB_BULK:
 210                         ND_PRINT("BULK");
 211                         break;
 212                 default:
 213                         ND_PRINT(" ?");
 214         }
 215
 216         event_type = GET_U_1(uh->event_type);
 217         switch(event_type)
 218         {
 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
 251 usb_linux_48_byte_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h,
 252                            const u_char *p)
 253 {
 254         ndo->ndo_protocol = "usb_linux_48_byte";
 255         if (h->caplen < sizeof(pcap_usb_header)) {
 256                 ndo->ndo_ll_hdr_len += h->caplen;
 257                 nd_print_trunc(ndo);
 258                 return;
 259         }
 260         ndo->ndo_ll_hdr_len += sizeof (pcap_usb_header);
 261
 262         usb_header_print(ndo, (const pcap_usb_header *) p);
 263 }
 264
 265 #ifdef DLT_USB_LINUX_MMAPPED
 266 /*
 267  * This is the top level routine of the printer for captures with a
 268  * 64-byte header.
 269  *
 270  * 'p' points to the header of the packet, 'h->ts' is the timestamp,
 271  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
 272  * is the number of bytes actually captured.
 273  */
 274 void
 275 usb_linux_64_byte_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h,
 276                            const u_char *p)
 277 {
 278         ndo->ndo_protocol = "usb_linux_64_byte";
 279         if (h->caplen < sizeof(pcap_usb_header_mmapped)) {
 280                 ndo->ndo_ll_hdr_len += h->caplen;
 281                 nd_print_trunc(ndo);
 282                 return;
 283         }
 284         ndo->ndo_ll_hdr_len += sizeof (pcap_usb_header_mmapped);
 285
 286         usb_header_print(ndo, (const pcap_usb_header *) p);
 287 }
 288 #endif /* DLT_USB_LINUX_MMAPPED */
 289
 290 #endif /* DLT_USB_LINUX */
 291