epan/dissectors/packet-rfid-pn532-hci.c

   1 /* packet-pn532_hci.c
   2  * Routines for NXP PN532 HCI Protocol
   3  *
   4  * http://www.nxp.com/documents/user_manual/141520.pdf
   5  *
   6  * Copyright 2013, Michal Labedzki for Tieto Corporation
   7  *
   8  * Wireshark - Network traffic analyzer
   9  * By Gerald Combs <gerald@wireshark.org>
  10  * Copyright 1998 Gerald Combs
  11  *
  12  * SPDX-License-Identifier: GPL-2.0-or-later
  13  */
  14
  15 #include "config.h"
  16
  17 #include <epan/packet.h>
  18 #include <epan/prefs.h>
  19 #include <epan/expert.h>
  20 #include "packet-usb.h"
  21
  22 static int proto_pn532_hci;
  23 static int hf_preamble;
  24 static int hf_start_code;
  25 static int hf_length;
  26 static int hf_length_checksum;
  27 static int hf_length_checksum_status;
  28 static int hf_extended_length;
  29 static int hf_packet_code;
  30 static int hf_postable;
  31 static int hf_specific_application_level_error_code;
  32 static int hf_data_checksum;
  33 static int hf_data_checksum_status;
  34 static int hf_ignored;
  35
  36 static int ett_pn532_hci;
  37
  38 static expert_field ei_invalid_length_checksum;
  39 static expert_field ei_invalid_data_checksum;
  40
  41 static dissector_handle_t  pn532_handle;
  42 static dissector_handle_t  pn532_hci_handle;
  43
  44 static const value_string packet_code_vals[] = {
  45     { 0x00FF,  "ACK Frame" },
  46     { 0x01FF,  "Error Frame" },
  47     { 0xFF00,  "NACK Frame" },
  48     { 0xFFFF,  "Extended Information Frame" },
  49     { 0, NULL }
  50 };
  51
  52 void proto_register_pn532_hci(void);
  53 void proto_reg_handoff_pn532_hci(void);
  54
  55 static int
  56 dissect_pn532_hci(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
  57 {
  58     proto_item      *main_item;
  59     proto_tree      *main_tree;
  60     int              offset = 0;
  61     tvbuff_t        *next_tvb;
  62     uint16_t         packet_code;
  63     uint16_t         length;
  64     uint8_t          checksum;
  65     urb_info_t      *urb;
  66
  67     /* Reject the packet if data is NULL */
  68     if (data == NULL)
  69         return 0;
  70     urb = (urb_info_t *)data;
  71
  72     length = tvb_captured_length_remaining(tvb, offset);
  73     if (length < 6) return offset;
  74
  75     col_set_str(pinfo->cinfo, COL_PROTOCOL, "PN532_HCI");
  76     col_clear(pinfo->cinfo, COL_INFO);
  77
  78     main_item = proto_tree_add_item(tree, proto_pn532_hci, tvb, offset, -1, ENC_NA);
  79     main_tree = proto_item_add_subtree(main_item, ett_pn532_hci);
  80
  81     length = 0;
  82     while (tvb_captured_length_remaining(tvb, length) >= 2 && tvb_get_ntohs(tvb, length) != 0x00FF) {
  83         length += 1;
  84     }
  85     if (length) {
  86         proto_tree_add_item(main_tree, hf_preamble, tvb, offset, length, ENC_NA);
  87         offset += length;
  88     }
  89
  90     proto_tree_add_item(main_tree, hf_start_code, tvb, offset, 2, ENC_BIG_ENDIAN);
  91     offset += 2;
  92
  93     packet_code = tvb_get_ntohs(tvb, offset);
  94     if (packet_code == 0x00FF) { /* ACK Frame */
  95         col_set_str(pinfo->cinfo, COL_INFO, val_to_str_const(packet_code, packet_code_vals, "Unknown frame"));
  96
  97         proto_tree_add_item(main_tree, hf_packet_code, tvb, offset, 2, ENC_BIG_ENDIAN);
  98         offset += 2;
  99     } else if (packet_code == 0xFF00) { /* NACK Frame */
 100         col_set_str(pinfo->cinfo, COL_INFO, val_to_str_const(packet_code, packet_code_vals, "Unknown frame"));
 101
 102         proto_tree_add_item(main_tree, hf_packet_code, tvb, offset, 2, ENC_BIG_ENDIAN);
 103         offset += 2;
 104     } else if (packet_code == 0x01FF) { /* Error Frame */
 105         col_set_str(pinfo->cinfo, COL_INFO, val_to_str_const(packet_code, packet_code_vals, "Unknown frame"));
 106
 107         proto_tree_add_item(main_tree, hf_packet_code, tvb, offset, 2, ENC_BIG_ENDIAN);
 108         offset += 2;
 109
 110         proto_tree_add_item(main_tree, hf_specific_application_level_error_code, tvb, offset, 1, ENC_BIG_ENDIAN);
 111         offset += 1;
 112     } else if (packet_code == 0xFFFF) { /* Extended Information Frame */
 113         col_set_str(pinfo->cinfo, COL_INFO, "Extended Information Frame");
 114
 115         proto_tree_add_item(main_tree, hf_extended_length, tvb, offset, 2, ENC_BIG_ENDIAN);
 116         length = tvb_get_ntohs(tvb, offset);
 117         offset += 2;
 118
 119         checksum = (length >> 8) + (length & 0xFF) + tvb_get_uint8(tvb, offset);
 120         proto_tree_add_checksum(main_tree, tvb, offset, hf_length_checksum, hf_length_checksum_status, &ei_invalid_length_checksum,
 121                             pinfo, checksum, ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY|PROTO_CHECKSUM_ZERO);
 122         offset += 1;
 123
 124         next_tvb = tvb_new_subset_length(tvb, offset, length);
 125         call_dissector_with_data(pn532_handle, next_tvb, pinfo, tree, urb);
 126         offset += length;
 127
 128         checksum = tvb_get_uint8(tvb, offset);
 129         while (length) {
 130             checksum += tvb_get_uint8(tvb, offset - length);
 131             length -= 1;
 132         }
 133         proto_tree_add_checksum(main_tree, tvb, offset, hf_data_checksum, hf_data_checksum_status, &ei_invalid_data_checksum, pinfo, 0,
 134                             ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY|PROTO_CHECKSUM_ZERO);
 135         offset += 1;
 136     } else { /* Normal Information Frame */
 137         col_set_str(pinfo->cinfo, COL_INFO, "Normal Information Frame");
 138
 139         proto_tree_add_item(main_tree, hf_length, tvb, offset, 1, ENC_BIG_ENDIAN);
 140         length = tvb_get_uint8(tvb, offset);
 141         offset += 1;
 142
 143         checksum = length + tvb_get_uint8(tvb, offset);
 144         proto_tree_add_checksum(main_tree, tvb, offset, hf_length_checksum, hf_length_checksum_status, &ei_invalid_length_checksum,
 145                             pinfo, checksum, ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY|PROTO_CHECKSUM_ZERO);
 146         offset += 1;
 147
 148         next_tvb = tvb_new_subset_length(tvb, offset, length);
 149         call_dissector_with_data(pn532_handle, next_tvb, pinfo, tree, urb);
 150         offset += length;
 151
 152         proto_tree_add_item(main_tree, hf_data_checksum, tvb, offset, 1, ENC_BIG_ENDIAN);
 153         checksum = tvb_get_uint8(tvb, offset);
 154         while (length) {
 155             checksum += tvb_get_uint8(tvb, offset - length);
 156             length -= 1;
 157         }
 158         if (checksum != 0) {
 159             proto_tree_add_expert(main_tree, pinfo, &ei_invalid_data_checksum, tvb, offset, 1);
 160         }
 161         offset += 1;
 162     }
 163
 164     length = 0;
 165     if (tvb_captured_length_remaining(tvb, offset) == 1) {
 166         length = 1;
 167     } else while (tvb_captured_length_remaining(tvb, offset + length) >= 2 && tvb_get_ntohs(tvb, offset + length) != 0x00FF) {
 168         length += 1;
 169     }
 170     if (length) {
 171         proto_tree_add_item(main_tree, hf_postable, tvb, offset, length, ENC_NA);
 172         offset += length;
 173     }
 174
 175     if (tvb_captured_length_remaining(tvb, offset)) {
 176         proto_tree_add_item(main_tree, hf_ignored, tvb, offset, tvb_captured_length_remaining(tvb, offset), ENC_NA);
 177         offset += tvb_captured_length_remaining(tvb, offset);
 178     }
 179
 180     return offset;
 181 }
 182
 183 void
 184 proto_register_pn532_hci(void)
 185 {
 186     module_t         *module;
 187     expert_module_t  *expert_module;
 188
 189     static hf_register_info hf[] = {
 190         { &hf_preamble,
 191             { "Preamble",                        "pn532_hci.preamble",
 192             FT_BYTES, BASE_NONE, NULL, 0x00,
 193             NULL, HFILL }
 194         },
 195         { &hf_start_code,
 196             { "Start Code",                      "pn532_hci.start_code",
 197             FT_UINT16, BASE_HEX, NULL, 0x00,
 198             NULL, HFILL }
 199         },
 200         { &hf_packet_code,
 201             { "Packet Code",                     "pn532_hci.packet_code",
 202             FT_UINT16, BASE_HEX, VALS(packet_code_vals), 0x00,
 203             NULL, HFILL }
 204         },
 205         { &hf_length,
 206             { "Length",                          "pn532_hci.length",
 207             FT_UINT8, BASE_DEC, NULL, 0x00,
 208             NULL, HFILL }
 209         },
 210         { &hf_extended_length,
 211             { "Extended Length",                 "pn532_hci.extended_length",
 212             FT_UINT16, BASE_DEC, NULL, 0x00,
 213             NULL, HFILL }
 214         },
 215         { &hf_length_checksum,
 216             { "Length Checksum",                 "pn532_hci.length_checksum",
 217             FT_UINT8, BASE_HEX, NULL, 0x00,
 218             NULL, HFILL }
 219         },
 220         { &hf_length_checksum_status,
 221             { "Length Checksum Status",            "pn532_hci.length_checksum.status",
 222             FT_UINT8, BASE_NONE, VALS(proto_checksum_vals), 0x00,
 223             NULL, HFILL }
 224         },
 225         { &hf_data_checksum,
 226             { "Data Checksum",                   "pn532_hci.data_checksum",
 227             FT_UINT8, BASE_HEX, NULL, 0x00,
 228             NULL, HFILL }
 229         },
 230         { &hf_data_checksum_status,
 231             { "Data Checksum Status",            "pn532_hci.data_checksum.status",
 232             FT_UINT8, BASE_NONE, VALS(proto_checksum_vals), 0x00,
 233             NULL, HFILL }
 234         },
 235         { &hf_specific_application_level_error_code,
 236             { "Specific Application Level Error Code","pn532_hci.specific_application_level_error_code",
 237             FT_UINT8, BASE_HEX, NULL, 0x00,
 238             NULL, HFILL }
 239         },
 240         { &hf_postable,
 241             { "Postamble",                       "pn532_hci.postamble",
 242             FT_BYTES, BASE_NONE, NULL, 0x00,
 243             NULL, HFILL }
 244         },
 245         { &hf_ignored,
 246             { "Ignored",                         "pn532_hci.ignored",
 247             FT_BYTES, BASE_NONE, NULL, 0x00,
 248             NULL, HFILL }
 249         }
 250     };
 251
 252     static int *ett[] = {
 253         &ett_pn532_hci
 254     };
 255
 256     static ei_register_info ei[] = {
 257         { &ei_invalid_length_checksum, { "pn532_hci.expert.invalid_length_checksum", PI_PROTOCOL, PI_WARN, "Invalid Length Checksum", EXPFILL }},
 258         { &ei_invalid_data_checksum,   { "pn532_hci.expert.invalid_data_checksum", PI_PROTOCOL, PI_WARN, "Invalid Data Checksum", EXPFILL }},
 259     };
 260
 261     proto_pn532_hci = proto_register_protocol("NXP PN532 HCI", "PN532_HCI", "pn532_hci");
 262     pn532_hci_handle = register_dissector("pn532_hci", dissect_pn532_hci, proto_pn532_hci);
 263
 264     proto_register_field_array(proto_pn532_hci, hf, array_length(hf));
 265     proto_register_subtree_array(ett, array_length(ett));
 266     expert_module = expert_register_protocol(proto_pn532_hci);
 267     expert_register_field_array(expert_module, ei, array_length(ei));
 268
 269     module = prefs_register_protocol(proto_pn532_hci, NULL);
 270     prefs_register_static_text_preference(module, "version",
 271             "PN532 HCI protocol version is based on: \"UM0701-02; PN532 User Manual\"",
 272             "Version of protocol supported by this dissector.");
 273 }
 274
 275 void
 276 proto_reg_handoff_pn532_hci(void)
 277 {
 278     pn532_handle = find_dissector_add_dependency("pn532", proto_pn532_hci);
 279
 280     dissector_add_uint("usb.product", (0x04e6 << 16) | 0x5591, pn532_hci_handle);
 281
 282     dissector_add_for_decode_as("usb.device", pn532_hci_handle);
 283     dissector_add_for_decode_as("usb.protocol", pn532_hci_handle);
 284 }
 285
 286 /*
 287  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 288  *
 289  * Local variables:
 290  * c-basic-offset: 4
 291  * tab-width: 8
 292  * indent-tabs-mode: nil
 293  * End:
 294  *
 295  * vi: set shiftwidth=4 tabstop=8 expandtab:
 296  * :indentSize=4:tabSize=8:noTabs=true:
 297  */