text: /* packet-iso7816.c
   * Routines for packet dissection of generic ISO 7816 smart card messages
   * Copyright 2012-2013 by Martin Kaiser <martin@kaiser.cx>
   *
   * Wireshark - Network traffic analyzer
   * By Gerald Combs <gerald@wireshark.org>
   * Copyright 1998 Gerald Combs
   *
   * SPDX-License-Identifier: GPL-2.0-or-later
   */
  
  /* This dissector supports the command and response apdu structure
   * as defined in ISO 7816-4. Detailed dissection of the APDUs defined
   * in the ISO 7816 specifications will be added in the future.
   *
   * The dissection of Answer To Reset (ATR) messages was made a separate
   * protocol so that it can be shared easily.
   */
  
  
  #include "config.h"
  
  #include <epan/packet.h>
  #include <epan/expert.h>
  #include <epan/decode_as.h>
  
  void proto_register_iso7816(void);
  void proto_reg_handoff_iso7816(void);
  
  static int proto_iso7816 = -1;
  static int proto_iso7816_atr = -1;
  
  static dissector_handle_t iso7816_handle;
  static dissector_handle_t iso7816_atr_handle;
  
  static wmem_tree_t *transactions = NULL;
  
  static dissector_table_t iso7816_apdu_pld_table;
  
  static int ett_iso7816 = -1;
  static int ett_iso7816_class = -1;
  static int ett_iso7816_param = -1;
  static int ett_iso7816_p1 = -1;
  static int ett_iso7816_p2 = -1;
  static int ett_iso7816_atr = -1;
  static int ett_iso7816_atr_ta = -1;
  static int ett_iso7816_atr_td = -1;
  
  static int hf_iso7816_atr_init_char = -1;
  static int hf_iso7816_atr_t0 = -1;
  static int hf_iso7816_atr_ta = -1;
  /* these two fields hold the converted values Fi and Di,
     not the binary representations FI and DI */
  static int hf_iso7816_atr_ta1_fi = -1;
  static int hf_iso7816_atr_ta1_di = -1;
  static int hf_iso7816_atr_tb = -1;
  static int hf_iso7816_atr_tc = -1;
  static int hf_iso7816_atr_td = -1;
  static int hf_iso7816_atr_next_ta_present = -1;
  static int hf_iso7816_atr_next_tb_present = -1;
  static int hf_iso7816_atr_next_tc_present = -1;
  static int hf_iso7816_atr_next_td_present = -1;
  static int hf_iso7816_atr_k = -1;
  static int hf_iso7816_atr_t = -1;
  static int hf_iso7816_atr_hist_bytes = -1;
  static int hf_iso7816_atr_tck = -1;
  
  static int hf_iso7816_resp_in = -1;
  static int hf_iso7816_resp_to = -1;
  static int hf_iso7816_cla = -1;
  static int hf_iso7816_cla_sm = -1;
  static int hf_iso7816_cla_channel = -1;
  static int hf_iso7816_ins = -1;
  static int hf_iso7816_p1 = -1;
  static int hf_iso7816_p2 = -1;
  static int hf_iso7816_lc = -1;
  static int hf_iso7816_le = -1;
  static int hf_iso7816_body = -1;
  static int hf_iso7816_sw1 = -1;
  static int hf_iso7816_sw2 = -1;
  static int hf_iso7816_sel_file_ctrl = -1;
  static int hf_iso7816_sel_file_fci_req = -1;
  static int hf_iso7816_sel_file_occ = -1;
  static int hf_iso7816_read_rec_ef = -1;
  static int hf_iso7816_read_rec_usage = -1;
  static int hf_iso7816_get_resp = -1;
  static int hf_iso7816_offset_first_byte = -1;
  static int hf_iso7816_rfu = -1;
  static int hf_iso7816_application_data = -1;
  
  static expert_field ie_iso7816_atr_tck_not1 = EI_INIT;
  
  #define ADDR_INTF "Interface"
  #define ADDR_CARD "Card"
  
  typedef struct _iso7816_transaction_t {
      guint32  cmd_frame;
      guint32  resp_frame;
      guint8   cmd_ins;  /* instruction byte in the command apdu */
      /* no need to add the channel number,
         the response contains no channel number to compare this to
         and the spec explicitly prohibits interleaving of command-response
         pairs, regardless of logical channels */
      dissector_handle_t handle;
  } iso7816_transaction_t;
  
  static const value_string iso7816_atr_init_char[] = {
      { 0x3B, "Direct convention (A==0, Z==1, MSB==m9)" },
      { 0x3F, "Inverse convention (A==1, Z==0, MSB==m2)" },
      { 0, NULL }
  };
  
  static const value_string iso7816_cla_sm[] = {
      { 0x00, "No SM" },
      { 0x01, "Proprietary SM" },
      { 0x02, "SM, command header not authenticated" },
      { 0x03, "SM, command header authenticated" },
      { 0, NULL }
  };
  
  #define INS_ERASE_BIN      0x0E
  #define INS_VRFY           0x20
  #define INS_MANAGE_CHANNEL 0x70
  #define INS_EXT_AUTH       0x82
  #define INS_GET_CHALLENGE  0x84
  #define INS_SELECT_FILE    0xA4
  #define INS_READ_BIN       0xB0
  #define INS_READ_REC       0xB2
  #define INS_GET_RESP       0xC0
  #define INS_ENVELOPE       0xC2
  #define INS_GET_DATA       0xCA
  #define INS_WRITE_BIN      0xD0
  #define INS_WRITE_REC      0xD2
  #define INS_UPDATE_BIN     0xD6
  #define INS_PUT_DATA       0xDA
  #define INS_UPDATE_REC     0xDC
  #define INS_APPEND_REC     0xE2
  /* for our transaction tracking, not defined in the specification */
  #define INS_INVALID        0x00
  
  static const value_string iso7816_ins[] = {
      /* instructions defined in ISO 7816-4 */
      { INS_ERASE_BIN,      "Erase binary" },
      { INS_VRFY,           "Verify" },
      { INS_MANAGE_CHANNEL, "Manage channel" },
      { INS_EXT_AUTH,       "External authenticate" },
      { INS_GET_CHALLENGE,  "Get challenge" },
      { INS_SELECT_FILE,    "Select file" },
      { INS_READ_BIN,       "Read binary" },
      { INS_READ_REC,       "Read record" },
      { INS_GET_RESP,       "Get response" },
      { INS_ENVELOPE,       "Envelope" },
      { INS_GET_DATA,       "Get data" },
      { INS_WRITE_BIN,      "Write binary" },
      { INS_WRITE_REC,      "Write record" },
      { INS_UPDATE_BIN,     "Update binary" },
      { INS_PUT_DATA,       "Put data" },
      { INS_UPDATE_REC,     "Update record" },
      { INS_APPEND_REC,     "Append record" },
      { 0, NULL }
  };
  static value_string_ext iso7816_ins_ext = VALUE_STRING_EXT_INIT(iso7816_ins);
  
  static const value_string iso7816_sel_file_ctrl[] = {
      { 0x00, "Select MF, DF or EF" },
      { 0x01, "Select child DF" },
      { 0x02, "Select EF under current DF" },
      { 0x03, "Select parent DF of the current DF" },
      { 0x04, "Direct selection by DF name" },
      { 0x08, "Selection by path from MF" },
      { 0x09, "Selection by path from current DF" },
      { 0, NULL }
  };
  static value_string_ext ext_iso7816_sel_file_ctrl =
      VALUE_STRING_EXT_INIT(iso7816_sel_file_ctrl);
  
  static const value_string iso7816_sel_file_fci_req[] = {
      { 0x00, "Return FCI, optional template" },
      { 0x01, "Return FCP template" },
      { 0x02, "Return FMD template" },
      { 0, NULL }
  };
  static value_string_ext ext_iso7816_sel_file_fci_req =
      VALUE_STRING_EXT_INIT(iso7816_sel_file_fci_req);
  
  static const value_string iso7816_sel_file_occ[] = {
      { 0x00, "First or only occurrence" },
      { 0x01, "Last occurrence" },
      { 0x02, "Next occurrence" },
      { 0x03, "Previous occurrence" },
      { 0, NULL }
  };
  static value_string_ext ext_iso7816_sel_file_occ =
      VALUE_STRING_EXT_INIT(iso7816_sel_file_occ);
  
  #define READ_REC_USAGE_SINGLE 0x04
  #define READ_REC_USAGE_START  0x05
  static const value_string iso7816_read_rec_usage[] = {
      { READ_REC_USAGE_SINGLE, "Read record P1" },
      { READ_REC_USAGE_START,  "Read all records from P1 up to the last" },
      { 0, NULL }
  };
  static value_string_ext ext_iso7816_read_rec_usage =
      VALUE_STRING_EXT_INIT(iso7816_read_rec_usage);
  
  static const range_string iso7816_sw1[] = {
    { 0x61, 0x61, "Normal processing" },
    { 0x62, 0x63, "Warning processing" },
    { 0x64, 0x65, "Execution error" },
    { 0x67, 0x6F, "Checking error" },
    { 0x90, 0x90, "Normal processing" },
    { 0,0,  NULL }
  };
  
  static const range_string iso7816_class_rvals[] = {
      {0x00, 0x0F, "structure and coding according to ISO/IEC 7816" },
      {0x10, 0x7F, "reserved for future use" },
      {0x80, 0x9F, "structure according to ISO/IEC 7816, coding is proprietary" },
      {0xA0, 0xAF, "structure and coding according to ISO/IEC 7816 unless specified otherwise by the application context" },
      {0xB0, 0xCF, "structure according to ISO/IEC 7816" },
      {0xD0, 0xFE, "proprietary structure and coding" },
      {0xFF, 0xFF, "reserved for Protocol Type Selection" },
      {0, 0,   NULL}
  };
  
  static const value_string unique_or_unused[] = {
      { 0, "or unused" },
      { 0, NULL }
  };
  
  static const value_string unique_max_num_available_bytes[] = {
      { 0, "maximum number of available bytes" },
      { 0, NULL }
  };
  
  static inline
  guint16 FI_to_Fi(guint8 FI)
  {
      if (FI<=1)
          return 372;
      else if (FI<=6)
          return (FI-1) * 372;
      else if (FI==9)
          return 512;
      else if (FI==10)
          return 768;
      else if (FI==11)
          return 1024;
      else if (FI==12)
          return 1536;
      else if (FI==13)
          return 2048;
  
      return 0; /* 0 means RFU (reserved for future use) here */
  }
  
  static inline
  guint8 DI_to_Di(guint8 DI)
  {
      if (DI>=1 && DI<=6)
          return 1 << (DI-1);
      else if (DI==8)
          return 12;
      else if (DI==9)
          return 20;
  
      return 0; /* 0 means RFU (reserved for future use) here */
  }
  
  /* dissect TA(ta_index) */
  static void
  dissect_iso7816_atr_ta(tvbuff_t *tvb, gint offset, guint ta_index,
          packet_info *pinfo _U_, proto_tree *tree)
  {
      guint8      ta, FI, DI;
      guint16     Fi;
      guint8      Di;
      proto_item *ta_it;
      proto_tree *ta_tree;
  
      ta = tvb_get_guint8(tvb, offset);
      ta_it = proto_tree_add_uint_format(tree, hf_iso7816_atr_ta,
              tvb, offset, 1, ta,
              "Interface character TA(%d): 0x%02x", ta_index, ta);
      ta_tree = proto_item_add_subtree(ta_it, ett_iso7816_atr_ta);
  
      if (ta_index==1) {
          FI = (tvb_get_guint8(tvb, offset) & 0xF0) >> 4;
          Fi = FI_to_Fi(FI);
          if (Fi>0) {
              proto_tree_add_uint_format(ta_tree, hf_iso7816_atr_ta1_fi,
                      tvb, offset, 1, Fi,
                      "Clock rate conversion factor Fi: %d (FI 0x%x)",
                      Fi, FI);
          }
  
          DI = tvb_get_guint8(tvb, offset) & 0x0F;
          Di = DI_to_Di(DI);
          if (Di>0) {
              proto_tree_add_uint_format(ta_tree, hf_iso7816_atr_ta1_di,
                      tvb, offset, 1, Di,
                      "Baud rate adjustment factor Di: %d (DI 0x%x)",
                      Di, DI);
          }
      }
  }
  
  static int
  dissect_iso7816_atr(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
  {
      gint        offset=0;
      guint8      init_char;
      guint       i=0;  /* loop index for TA(i)...TD(i) */
      proto_item *proto_it;
      proto_tree *proto_tr;
      guint8      tb, tc, td, k=0;
      gint        tck_len;
  
      /* we need at least the initial char TS and the format char T0 */
      if (tvb_captured_length(tvb) < 2)
          return 0; /* no ATR sequence */
  
      init_char = tvb_get_guint8(tvb, offset);
      if (init_char!=0x3B && init_char!=0x3F)
          return 0;
  
      proto_it = proto_tree_add_protocol_format(tree, proto_iso7816_atr,
                  tvb, 0, -1, "ISO 7816 ATR");
      proto_tr = proto_item_add_subtree(proto_it, ett_iso7816_atr);
  
      col_append_sep_str(pinfo->cinfo, COL_INFO, NULL, "ATR");
  
      /* ISO 7816-4, section 4 indicates that concatenations are big endian */
      proto_tree_add_item(proto_tr, hf_iso7816_atr_init_char,
              tvb, offset, 1, ENC_BIG_ENDIAN);
      offset++;
  
      do {
          proto_item *td_it;
          proto_tree *td_tree;
  
          /* for i==0, this is the T0 byte, otherwise it's the TD(i) byte
             in each loop, we dissect T0/TD(i) and TA(i+1), TB(i+1), TC(i+1) */
          td = tvb_get_guint8(tvb, offset);
          if (i==0) {
              td_it = proto_tree_add_item(proto_tr, hf_iso7816_atr_t0,
                      tvb, offset, 1, ENC_BIG_ENDIAN);
          }
          else {
              td_it = proto_tree_add_uint_format(proto_tr, hf_iso7816_atr_td,
                      tvb, offset, 1, td,
                      "Interface character TD(%d): 0x%02x", i, td);
          }
          td_tree = proto_item_add_subtree(td_it, ett_iso7816_atr_td);
  
          proto_tree_add_boolean_format(td_tree, hf_iso7816_atr_next_ta_present,
                  tvb, offset, 1, td&0x10,
                  "TA(%d) present: %s", i+1, td&0x10 ? "True" : "False");
          proto_tree_add_boolean_format(td_tree, hf_iso7816_atr_next_tb_present,
                  tvb, offset, 1, td&0x20,
                  "TB(%d) present: %s", i+1, td&0x20 ? "True" : "False");
          proto_tree_add_boolean_format(td_tree, hf_iso7816_atr_next_tc_present,
                  tvb, offset, 1, td&0x40,
                  "TC(%d) present: %s", i+1, td&0x40 ? "True" : "False");
          proto_tree_add_boolean_format(td_tree, hf_iso7816_atr_next_td_present,
                  tvb, offset, 1, td&0x80,
                  "TD(%d) present: %s", i+1, td&0x80 ? "True" : "False");
  
          col_append_sep_fstr(pinfo->cinfo, COL_INFO, NULL,
                  "TA(%d)=%s TB(%d)=%s TC(%d)=%s TD(%d)=%s",
                  i+1, td&0x10 ? "True" : "False",
                  i+1, td&0x20 ? "True" : "False",
                  i+1, td&0x40 ? "True" : "False",
                  i+1, td&0x80 ? "True" : "False");
  
          if (i==0) {
              k = td&0x0F;   /* number of historical bytes */
              proto_tree_add_item(td_tree, hf_iso7816_atr_k,
                      tvb, offset, 1, ENC_BIG_ENDIAN);
          }
          else {
              proto_tree_add_item(td_tree, hf_iso7816_atr_t,
                      tvb, offset, 1, ENC_BIG_ENDIAN);
          }
          offset++;
  
          if (td&0x10) {
              /* we read TA(i+1), see comment above */
              dissect_iso7816_atr_ta(tvb, offset, i+1, pinfo, proto_tr);
              offset++;
          }
          if (td&0x20) {
              tb = tvb_get_guint8(tvb, offset);
              proto_tree_add_uint_format(proto_tr, hf_iso7816_atr_tb,
                      tvb, offset, 1, tb,
                      "Interface character TB(%d): 0x%02x", i+1, tb);
              offset++;
          }
          if (td&0x40) {
              tc = tvb_get_guint8(tvb, offset);
              proto_tree_add_uint_format(proto_tr, hf_iso7816_atr_tc,
                      tvb, offset, 1, tc,
                      "Interface character TC(%d): 0x%02x", i+1, tc);
              offset++;
          }
  
          i++;
      } while (td&0x80);
  
      if (k>0) {
          proto_tree_add_item(proto_tr, hf_iso7816_atr_hist_bytes,
                  tvb, offset, k, ENC_NA);
          offset += k;
      }
  
      tck_len = tvb_reported_length_remaining(tvb, offset);
      /* tck is either absent or exactly one byte */
      if (tck_len==1) {
          proto_tree_add_item(proto_tr, hf_iso7816_atr_tck,
                  tvb, offset, 1, ENC_BIG_ENDIAN);
          offset++;
      }
      else if (tck_len>1) {
          proto_tree_add_expert(proto_tr, pinfo, &ie_iso7816_atr_tck_not1,
                  tvb, offset, tck_len);
      }
  
      proto_item_set_len(proto_it, offset);
      return offset;
  }
  
  /* Dissect the class byte. Return 1 if the APDU's structure and coding
     adhere to ISO 7816. In this case, we can dissect the rest of the
     APDU. Otherwise, return -1. We may then pass the APDU to other
     dissectors. */
  static gint
  dissect_iso7816_class(tvbuff_t *tvb, gint offset,
          packet_info *pinfo _U_, proto_tree *tree)
  {
      proto_item *class_item;
      proto_tree *class_tree;
      guint8      dev_class;
  
      class_item = proto_tree_add_item(tree, hf_iso7816_cla,
              tvb, offset, 1, ENC_BIG_ENDIAN);
      class_tree = proto_item_add_subtree(class_item, ett_iso7816_class);
  
      dev_class = tvb_get_guint8(tvb, offset);
  
      if (dev_class>=0x10 && dev_class<=0x7F) {
          /* these values are RFU. */
          return -1;
      }
  
      if (dev_class>=0xD0 && dev_class<=0xFE) {
          /* proprietary structure and coding */
          return -1;
      }
  
      if (dev_class==0xFF) {
          /* reserved for Protocol Type Selection */
          return -1;
      }
  
      /* If we made it this far, the structrue of the APDU is compliant
         with ISO 7816. */
  
      proto_tree_add_item(class_tree, hf_iso7816_cla_sm,
              tvb, offset, 1, ENC_BIG_ENDIAN);
  
      proto_tree_add_item(class_tree, hf_iso7816_cla_channel,
              tvb, offset, 1, ENC_BIG_ENDIAN);
  
      if (dev_class>=0x80 && dev_class<=0x9F) {
          /* structure according to ISO 7816, coding is proprietary */
          return -1;
      }
  
      if (dev_class>=0xB0 && dev_class<=0xCF) {
          /* structure according to ISO 7816 */
          return -1;
      }
  
      /* both structure and coding according to ISO 7816 */
      return 1;
  }
  
  /* dissect the parameters p1 and p2
     return number of dissected bytes or -1 for error */
  static gint
  dissect_iso7816_params(guint8 ins, tvbuff_t *tvb, gint offset,
                   packet_info *pinfo _U_, proto_tree *tree)
  {
      gint        offset_start, p1_offset, p2_offset;
      proto_tree *params_tree;
      guint8      p1, p2;
      proto_item *p1_it = NULL, *p2_it = NULL;
      proto_tree *p1_tree = NULL, *p2_tree = NULL;
      proto_item *p1_p2_it = NULL;
      guint16     P1P2;
      guint32     ef, read_rec_usage;
  
      offset_start = offset;
  
      params_tree = proto_tree_add_subtree(tree, tvb, offset_start, 2,
                                  ett_iso7816_param, NULL, "Parameters");
  
      p1 = tvb_get_guint8(tvb,offset);
      p1_it = proto_tree_add_item(params_tree, hf_iso7816_p1, tvb,
              offset, 1, ENC_BIG_ENDIAN);
      p1_offset = offset;
      offset++;
      p2 = tvb_get_guint8(tvb,offset);
      p2_it = proto_tree_add_item(params_tree, hf_iso7816_p2,
              tvb, offset, 1, ENC_BIG_ENDIAN);
      p2_offset = offset;
      offset++;
      P1P2 = (p1<<8|p2);
  
      switch (ins) {
          case INS_EXT_AUTH:
              if (p1>0) {
                  proto_item_append_text(p1_it,
                          " (reference of the algorithm on the card)");
              }
              proto_item_append_text(p2_it, " (reference of the secret)");
              break;
          case INS_SELECT_FILE:
              proto_item_append_text(p1_it, " (selection control)");
              p1_tree = proto_item_add_subtree(p1_it, ett_iso7816_p1);
              proto_tree_add_item(p1_tree, hf_iso7816_sel_file_ctrl,
                      tvb, p1_offset, 1, ENC_BIG_ENDIAN);
              proto_item_append_text(p2_it, " (selection options)");
              p2_tree = proto_item_add_subtree(p2_it, ett_iso7816_p2);
              proto_tree_add_item(p2_tree, hf_iso7816_sel_file_fci_req,
                      tvb, p2_offset, 1, ENC_BIG_ENDIAN);
              proto_tree_add_item(p2_tree, hf_iso7816_sel_file_occ,
                      tvb, p2_offset, 1, ENC_BIG_ENDIAN);
              break;
          case INS_READ_BIN:
              if (p1&0x80) {
                  /* XXX - b5-b1 of P1 == short ef identifier for the selected file */
                  /* XXX - P2 == offset for the read */
              }
              else {
                  p1_p2_it = proto_tree_add_uint(params_tree, hf_iso7816_offset_first_byte,
                          tvb, offset_start, offset-offset_start, P1P2);
                  col_append_sep_fstr(pinfo->cinfo, COL_INFO, NULL,
                          "offset %d", P1P2);
              }
              break;
          case INS_READ_REC:
              proto_item_append_text(p1_it, " (record number)");
              proto_item_append_text(p2_it, " (reference control)");
              p2_tree = proto_item_add_subtree(p2_it, ett_iso7816_p2);
              proto_tree_add_item_ret_uint(p2_tree, hf_iso7816_read_rec_ef,
                      tvb, p2_offset, 1, ENC_BIG_ENDIAN, &ef);
              col_append_sep_fstr(pinfo->cinfo, COL_INFO, NULL, "EF %d", ef);
              proto_tree_add_item_ret_uint(p2_tree, hf_iso7816_read_rec_usage,
                      tvb, p2_offset, 1, ENC_BIG_ENDIAN, &read_rec_usage);
              if (read_rec_usage == READ_REC_USAGE_SINGLE) {
                  col_append_sep_fstr(
                          pinfo->cinfo, COL_INFO, NULL, "record %d", p1);
              }
              break;
          case INS_GET_RESP:
              p1_p2_it = proto_tree_add_uint_format(params_tree, hf_iso7816_get_resp,
                      tvb, offset_start, offset-offset_start, P1P2,
                      "Both should be 0x00, other values are RFU");
              break;
          case INS_GET_DATA:
              if (P1P2<=0x003F || (0x0300<=P1P2 && P1P2<=0x3FFF)) {
                  p1_p2_it = proto_tree_add_uint(params_tree, hf_iso7816_rfu,
                          tvb, offset_start, offset-offset_start, P1P2);
              }
              else if (0x0100<=P1P2 && P1P2<=0x01FF) {
                  p1_p2_it = proto_tree_add_uint(params_tree, hf_iso7816_application_data,
                          tvb, offset_start, offset-offset_start, P1P2);
              }
              break;
          default:
              break;
      }
  
      proto_item_set_generated(p1_p2_it);
  
      return 2;
  }
  
  static gint
  dissect_iso7816_le(
          tvbuff_t *tvb, gint offset, packet_info *pinfo _U_, proto_tree *tree)
  {
      proto_tree_add_item(tree, hf_iso7816_le, tvb, offset, 1, ENC_BIG_ENDIAN);
  
      return 1;
  }
  
  
  static gint
  dissect_iso7816_cmd_apdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
  {
      iso7816_transaction_t *iso7816_trans = NULL;
      proto_item            *trans_ti = NULL;
      gint                   ret;
      gint                   offset = 0;
      guint8                 ins;
      gint                   body_len;
      guint8                 lc;
  
  
      if (PINFO_FD_VISITED(pinfo)) {
          iso7816_trans = (iso7816_transaction_t *)wmem_tree_lookup32(
                  transactions, pinfo->num);
          if (iso7816_trans && iso7816_trans->cmd_frame==pinfo->num &&
                  iso7816_trans->resp_frame!=0) {
              trans_ti = proto_tree_add_uint_format(tree, hf_iso7816_resp_in,
                             NULL, 0, 0, iso7816_trans->resp_frame,
                             "Response in frame %d", iso7816_trans->resp_frame);
              proto_item_set_generated(trans_ti);
          }
      }
      else {
          if (transactions) {
              iso7816_trans = wmem_new(wmem_file_scope(), iso7816_transaction_t);
              iso7816_trans->cmd_frame = pinfo->num;
              iso7816_trans->resp_frame = 0;
              iso7816_trans->cmd_ins = INS_INVALID;
              iso7816_trans->handle = NULL;
  
              wmem_tree_insert32(transactions,
                      iso7816_trans->cmd_frame, (void *)iso7816_trans);
          }
      }
  
      ret = dissect_iso7816_class(tvb, offset, pinfo, tree);
      if (ret==-1) {
          /* the class byte says that the remaining APDU is not
              in ISO7816 format */
  
          iso7816_trans->handle =
              dissector_get_payload_handle(iso7816_apdu_pld_table);
          if (iso7816_trans->handle != NULL) {
              ret = call_dissector(iso7816_trans->handle, tvb, pinfo, tree);
              if (ret == 0) {
                  col_append_sep_str(pinfo->cinfo, COL_INFO, NULL,
                          "Command APDU using proprietary format");
                  return 1; /* we only dissected the class byte */
              }
          }
  
          return ret;
      }
      offset += ret;
  
      ins = tvb_get_guint8(tvb, offset);
      proto_tree_add_item(tree, hf_iso7816_ins, tvb, offset, 1, ENC_BIG_ENDIAN);
      col_append_sep_str(pinfo->cinfo, COL_INFO, NULL,
              val_to_str_ext_const(ins, &iso7816_ins_ext, "Unknown instruction"));
      offset++;
      /* if we just created a new transaction, we can now fill in the cmd id */
      if (iso7816_trans && iso7816_trans->cmd_ins==INS_INVALID)
          iso7816_trans->cmd_ins = ins;
  
      ret = dissect_iso7816_params(ins, tvb, offset, pinfo, tree);
      if (ret>0)
          offset += ret;
  
      /* for now, we support only short length fields
         based on infos from the ATR, we could support extended length fields too */
      body_len = tvb_reported_length_remaining(tvb, offset);
  
      /* nothing to do for body_len==0 */
      if (body_len==1) {
          offset += dissect_iso7816_le(tvb, offset, pinfo, tree);
      }
      else if (body_len>1) {
          lc = tvb_get_guint8(tvb, offset);
          proto_tree_add_item(
                  tree, hf_iso7816_lc, tvb, offset, 1, ENC_BIG_ENDIAN);
          offset++;
          if (lc>0) {
              proto_tree_add_item(tree, hf_iso7816_body, tvb, offset, lc, ENC_NA);
              offset += lc;
          }
          if (tvb_reported_length_remaining(tvb, offset)>0) {
              offset += dissect_iso7816_le(tvb, offset, pinfo, tree);
          }
      }
  
      return offset;
  }
  
  static gint
  dissect_iso7816_resp_apdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
  {
      iso7816_transaction_t *iso7816_trans;
      proto_item            *trans_ti = NULL;
      const gchar           *cmd_ins_str;
      gint                   offset = 0;
      gint                   body_len;
  
      col_append_sep_str(pinfo->cinfo, COL_INFO, NULL, "Response APDU");
  
      if (transactions) {
          /* receive the largest key that is less than or equal to our frame
             number */
          iso7816_trans = (iso7816_transaction_t *)wmem_tree_lookup32_le(
                  transactions, pinfo->num);
          if (iso7816_trans) {
              if (iso7816_trans->resp_frame==0) {
                  /* there's a pending request, this packet is the response */
                  iso7816_trans->resp_frame = pinfo->num;
              }
  
              if (iso7816_trans->resp_frame== pinfo->num) {
                  /* we found the request that corresponds to our response */
                  cmd_ins_str = val_to_str_const(iso7816_trans->cmd_ins,
                          iso7816_ins, "Unknown instruction");
                  trans_ti = proto_tree_add_uint_format(tree, hf_iso7816_resp_to,
                          NULL, 0, 0, iso7816_trans->cmd_frame,
                          "Response to frame %d (%s)",
                          iso7816_trans->cmd_frame, cmd_ins_str);
                  proto_item_set_generated(trans_ti);
  
                  col_append_sep_fstr(pinfo->cinfo, COL_INFO, " ",
                          "(to %s)", cmd_ins_str);
              }
  
              if (iso7816_trans->handle != NULL)
                  call_dissector(iso7816_trans->handle, tvb, pinfo, tree);
          }
      }
  
      /* - 2 bytes SW1, SW2 */
      body_len = tvb_reported_length_remaining(tvb, offset) - 2;
  
      if (body_len>0) {
          proto_tree_add_item(tree, hf_iso7816_body,
                  tvb, offset, body_len, ENC_NA);
          offset += body_len;
      }
  
      if (tvb_reported_length_remaining(tvb, offset) >= 2) {
          proto_tree_add_item(tree, hf_iso7816_sw1,
                  tvb, offset, 1, ENC_BIG_ENDIAN);
          offset++;
          proto_tree_add_item(tree, hf_iso7816_sw2,
                  tvb, offset, 1, ENC_BIG_ENDIAN);
          offset++;
      }
  
      return offset;
  }
  
  static int
  dissect_iso7816(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
  {
      gint        offset = 0;
      proto_item *tree_ti;
      proto_tree *iso7816_tree;
      gboolean    is_atr = FALSE;
  
      if (pinfo->p2p_dir!=P2P_DIR_SENT && pinfo->p2p_dir!=P2P_DIR_RECV)
          return 0;
  
      col_set_str(pinfo->cinfo, COL_PROTOCOL, "ISO 7816");
      col_clear(pinfo->cinfo, COL_INFO);
  
      tree_ti = proto_tree_add_protocol_format(tree, proto_iso7816,
              tvb, 0, tvb_reported_length(tvb), "ISO 7816");
      iso7816_tree = proto_item_add_subtree(tree_ti, ett_iso7816);
  
      /* per our definition, sent/received is from the perspective of the interface
         i.e sent is from interface to card, received is from card to interface */
      if (pinfo->p2p_dir==P2P_DIR_SENT) {
          set_address(&pinfo->src, AT_STRINGZ,
                  (int)strlen(ADDR_INTF)+1, ADDR_INTF);
          set_address(&pinfo->dst, AT_STRINGZ,
                  (int)strlen(ADDR_CARD)+1, ADDR_CARD);
          proto_item_append_text(tree_ti, " Command APDU");
          offset = dissect_iso7816_cmd_apdu(tvb, pinfo, iso7816_tree);
      }
      else if (pinfo->p2p_dir==P2P_DIR_RECV) {
          set_address(&pinfo->src, AT_STRINGZ,
                  (int)strlen(ADDR_CARD)+1, ADDR_CARD);
          set_address(&pinfo->dst, AT_STRINGZ,
                  (int)strlen(ADDR_INTF)+1, ADDR_INTF);
  
          if (iso7816_atr_handle) {
              offset = call_dissector_only(iso7816_atr_handle,
                      tvb, pinfo, iso7816_tree, NULL);
              if (offset > 0)
                  is_atr = TRUE;
          }
          if (!is_atr) {
              proto_item_append_text(tree_ti, " Response APDU");
              offset = dissect_iso7816_resp_apdu(tvb, pinfo, iso7816_tree);
          }
      }
  
      return offset;
  }
  
  void
  proto_register_iso7816(void)
  {
      static hf_register_info hf[] = {
          { &hf_iso7816_atr_init_char,
              { "Initial character", "iso7816.atr.init_char",
                  FT_UINT8, BASE_HEX, VALS(iso7816_atr_init_char), 0, NULL, HFILL }
          },
          { &hf_iso7816_atr_t0,
              { "Format character T0", "iso7816.atr.t0",
                  FT_UINT8, BASE_HEX, NULL, 0, NULL, HFILL }
          },
          { &hf_iso7816_atr_ta,
              { "Interface character TA(i)", "iso7816.atr.ta",
                  FT_UINT8, BASE_HEX, NULL, 0, NULL, HFILL }
          },
          { &hf_iso7816_atr_ta1_fi,
              { "Fi", "iso7816.atr.ta1.fi",
                  FT_UINT16, BASE_DEC, NULL, 0, NULL, HFILL }
          },
          { &hf_iso7816_atr_ta1_di,
              { "Di", "iso7816.atr.ta1.di",
                  FT_UINT8, BASE_DEC, NULL, 0, NULL, HFILL }
          },
          { &hf_iso7816_atr_tb,
              { "Interface character TB(i)", "iso7816.atr.tb",
                  FT_UINT8, BASE_HEX, NULL, 0, NULL, HFILL }
          },
          { &hf_iso7816_atr_tc,
              { "Interface character TC(i)", "iso7816.atr.tc",
                  FT_UINT8, BASE_HEX, NULL, 0, NULL, HFILL }
          },
          { &hf_iso7816_atr_td,
              { "Interface character TD(i)", "iso7816.atr.td",
                  FT_UINT8, BASE_HEX, NULL, 0, NULL, HFILL }
          },
          { &hf_iso7816_atr_next_ta_present,
              { "TA(i+1) present", "iso7816.atr.next_ta_present",
                  FT_BOOLEAN, BASE_HEX, NULL, 0x10, NULL, HFILL }
          },
          { &hf_iso7816_atr_next_tb_present,
              { "TB(i+1) present", "iso7816.atr.next_tb_present",
                  FT_BOOLEAN, BASE_HEX, NULL, 0x20, NULL, HFILL }
          },
          { &hf_iso7816_atr_next_tc_present,
              { "TC(i+1) present", "iso7816.atr.next_tc_present",
                  FT_BOOLEAN, BASE_HEX, NULL, 0x40, NULL, HFILL }
          },
          { &hf_iso7816_atr_next_td_present,
              { "TD(i+1) present", "iso7816.atr.next_td_present",
                  FT_BOOLEAN, BASE_HEX, NULL, 0x80, NULL, HFILL }
          },
          { &hf_iso7816_atr_k,
              { "Number K of historical bytes", "iso7816.atr.k",
                  FT_UINT8, BASE_DEC, NULL, 0x0F, NULL, HFILL }
          },
          { &hf_iso7816_atr_t,
              { "Protocol reference T", "iso7816.atr.t",
                  FT_UINT8, BASE_HEX, NULL, 0x0F, NULL, HFILL }
          },
          { &hf_iso7816_atr_hist_bytes,
              { "Historical bytes", "iso7816.atr.historical_bytes",
                  FT_BYTES, BASE_NONE, NULL, 0, NULL, HFILL }
          },
          { &hf_iso7816_atr_tck,
              { "Check character TCK", "iso7816.atr.tck",
                  FT_UINT8, BASE_HEX, NULL, 0, NULL, HFILL }
          },
          { &hf_iso7816_resp_in,
              { "Response In", "iso7816.resp_in",
                  FT_FRAMENUM, BASE_NONE, NULL, 0x0,
                  "The response to this command is in this frame", HFILL }
          },
          { &hf_iso7816_resp_to,
              { "Response To", "iso7816.resp_to",
                  FT_FRAMENUM, BASE_NONE, NULL, 0x0,
                  "This is the response to the command in this frame", HFILL }
          },
          { &hf_iso7816_cla,
              { "Class", "iso7816.apdu.cla",
                  FT_UINT8, BASE_HEX|BASE_RANGE_STRING, RVALS(iso7816_class_rvals), 0, NULL , HFILL }
          },
          { &hf_iso7816_cla_sm,
              { "Secure Messaging", "iso7816.apdu.cla.sm",
                  FT_UINT8, BASE_HEX, VALS(iso7816_cla_sm), 0x0C, NULL , HFILL }
          },
          { &hf_iso7816_cla_channel,
              { "Logical channel number", "iso7816.apdu.cla.channel",
                  FT_UINT8, BASE_HEX|BASE_SPECIAL_VALS, VALS(unique_or_unused), 0x03, NULL , HFILL }
          },
          { &hf_iso7816_ins,
              { "Instruction", "iso7816.apdu.ins",
                  FT_UINT8, BASE_HEX | BASE_EXT_STRING, &iso7816_ins_ext, 0, NULL, HFILL }
          },
          { &hf_iso7816_p1,
              { "Parameter 1", "iso7816.apdu.p1",
                  FT_UINT8, BASE_HEX, NULL, 0, NULL, HFILL }
          },
          { &hf_iso7816_p2,
              { "Parameter 2", "iso7816.apdu.p2",
                  FT_UINT8, BASE_HEX, NULL, 0, NULL, HFILL }
          },
          { &hf_iso7816_lc,
              { "Length field Lc", "iso7816.apdu.lc",
                  FT_UINT8, BASE_HEX, NULL, 0, NULL, HFILL }
          },
          { &hf_iso7816_le,
              { "Expected response length Le", "iso7816.apdu.le",
                  FT_UINT8, BASE_HEX|BASE_SPECIAL_VALS, VALS(unique_max_num_available_bytes), 0, NULL, HFILL }
          },
          { &hf_iso7816_body,
              { "APDU Body", "iso7816.apdu.body",
                  FT_BYTES, BASE_NONE, NULL, 0, NULL, HFILL }
          },
          { &hf_iso7816_sw1,
              { "Status Word SW1", "iso7816.apdu.sw1", FT_UINT8,
                  BASE_RANGE_STRING|BASE_HEX, RVALS(iso7816_sw1), 0, NULL, HFILL }
          },
          { &hf_iso7816_sw2,
              { "Status Word SW2", "iso7816.apdu.sw2",
                  FT_UINT8, BASE_HEX, NULL, 0, NULL, HFILL }
          },
          { &hf_iso7816_sel_file_ctrl,
              { "Selection control", "iso7816.apdu.select_file.ctrl",
                  FT_UINT8, BASE_HEX | BASE_EXT_STRING,
                  &ext_iso7816_sel_file_ctrl, 0, NULL, HFILL }
          },
          { &hf_iso7816_sel_file_fci_req,
              { "File control information request", "iso7816.apdu.select_file.fci_req",
                  FT_UINT8, BASE_HEX | BASE_EXT_STRING,
                  &ext_iso7816_sel_file_fci_req, 0x0C, NULL, HFILL }
          },
          { &hf_iso7816_sel_file_occ,
              { "Occurrence", "iso7816.apdu.select_file.occurrence",
                  FT_UINT8, BASE_HEX | BASE_EXT_STRING,
                  &ext_iso7816_sel_file_occ, 0x03, NULL, HFILL }
          },
          { &hf_iso7816_read_rec_ef,
              { "Short EF identifier", "iso7816.apdu.read_rec.ef",
                  FT_UINT8, BASE_HEX, NULL, 0xF8, NULL, HFILL }
          },
          { &hf_iso7816_read_rec_usage,
              { "Usage", "iso7816.apdu.read_rec.usage",
                  FT_UINT8, BASE_HEX | BASE_EXT_STRING,
                  &ext_iso7816_read_rec_usage, 0x07, NULL, HFILL }
          },
          { &hf_iso7816_offset_first_byte,
              { "Offset of the first byte to read", "iso7816.offset_first_byte",
                  FT_UINT16, BASE_DEC, NULL, 0, NULL, HFILL }
          },
          { &hf_iso7816_get_resp,
              { "GetResp", "iso7816.get_resp",
                  FT_UINT16, BASE_HEX, NULL, 0, NULL, HFILL }
          },
          { &hf_iso7816_rfu,
              { "RFU", "iso7816.rfu",
                  FT_UINT16, BASE_HEX, NULL, 0, NULL, HFILL }
          },
          { &hf_iso7816_application_data,
              { "Application data (proprietary coding)", "iso7816.application_data",
                  FT_UINT16, BASE_HEX, NULL, 0, NULL, HFILL }
          },
      };
      static gint *ett[] = {
          &ett_iso7816,
          &ett_iso7816_class,
          &ett_iso7816_param,
          &ett_iso7816_p1,
          &ett_iso7816_p2,
          &ett_iso7816_atr,
          &ett_iso7816_atr_ta,
          &ett_iso7816_atr_td
      };
  
      static ei_register_info ei[] = {
          { &ie_iso7816_atr_tck_not1, { "iso7816.atr.tck.not1", PI_PROTOCOL, PI_WARN, "TCK byte must either be absent or exactly one byte", EXPFILL }}
      };
  
      expert_module_t* expert_iso7816;
  
      proto_iso7816 = proto_register_protocol(
              "ISO/IEC 7816", "ISO 7816", "iso7816");
      proto_register_field_array(proto_iso7816, hf, array_length(hf));
      proto_register_subtree_array(ett, array_length(ett));
      expert_iso7816 = expert_register_protocol(proto_iso7816);
      expert_register_field_array(expert_iso7816, ei, array_length(ei));
  
      iso7816_handle = register_dissector("iso7816", dissect_iso7816, proto_iso7816);
  
      transactions = wmem_tree_new_autoreset(wmem_epan_scope(), wmem_file_scope());
  
      proto_iso7816_atr = proto_register_protocol_in_name_only("ISO/IEC 7816-3", "ISO 7816-3", "iso7816.atr", proto_iso7816, FT_PROTOCOL);
      iso7816_atr_handle = register_dissector("iso7816.atr", dissect_iso7816_atr, proto_iso7816_atr);
  
      iso7816_apdu_pld_table =
          register_decode_as_next_proto(proto_iso7816,
                  "iso7816.apdu_payload",
                  "ISO7816 proprietary APDU dissector", NULL);
  }
  
  
  void proto_reg_handoff_iso7816(void)
  {
      dissector_add_for_decode_as("usbccid.subdissector", iso7816_handle);
      dissector_add_for_decode_as("iso14443.subdissector", iso7816_handle);
  }
  
  
  /*
   * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
   *
   * Local variables:
   * c-basic-offset: 4
   * tab-width: 8
   * indent-tabs-mode: nil
   * End:
   *
   * vi: set shiftwidth=4 tabstop=8 expandtab:
   * :indentSize=4:tabSize=8:noTabs=true:
   */
  