/* 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;

static int proto_iso7816_atr;

static dissector_handle_t iso7816_handle;

static dissector_handle_t iso7816_atr_handle;

static wmem_tree_t *transactions;

static dissector_table_t iso7816_apdu_pld_table;

static int ett_iso7816;

static int ett_iso7816_class;

static int ett_iso7816_param;

static int ett_iso7816_p1;

static int ett_iso7816_p2;

static int ett_iso7816_atr;

static int ett_iso7816_atr_ta;

static int ett_iso7816_atr_td;

static int hf_iso7816_atr_init_char;

static int hf_iso7816_atr_t0;

static int hf_iso7816_atr_ta;

/* these two fields hold the converted values Fi and Di,

   not the binary representations FI and DI */

static int hf_iso7816_atr_ta1_fi;

static int hf_iso7816_atr_ta1_di;

static int hf_iso7816_atr_tb;

static int hf_iso7816_atr_tc;

static int hf_iso7816_atr_td;

static int hf_iso7816_atr_next_ta_present;

static int hf_iso7816_atr_next_tb_present;

static int hf_iso7816_atr_next_tc_present;

static int hf_iso7816_atr_next_td_present;

static int hf_iso7816_atr_k;

static int hf_iso7816_atr_t;

static int hf_iso7816_atr_hist_bytes;

static int hf_iso7816_atr_tck;

static int hf_iso7816_resp_in;

static int hf_iso7816_resp_to;

static int hf_iso7816_cla;

static int hf_iso7816_cla_sm;

static int hf_iso7816_cla_channel;

static int hf_iso7816_ins;

static int hf_iso7816_p1;

static int hf_iso7816_p2;

static int hf_iso7816_lc;

static int hf_iso7816_le;

static int hf_iso7816_body;

static int hf_iso7816_sw1;

static int hf_iso7816_sw2;

static int hf_iso7816_sel_file_ctrl;

static int hf_iso7816_sel_file_fci_req;

static int hf_iso7816_sel_file_occ;

static int hf_iso7816_read_rec_ef;

static int hf_iso7816_read_rec_usage;

static int hf_iso7816_get_resp;

static int hf_iso7816_offset_first_byte;

static int hf_iso7816_rfu;

static int hf_iso7816_application_data;

static expert_field ei_iso7816_atr_tck_not1;

#define ADDR_INTF "Interface"

#define ADDR_CARD "Card"

typedef struct _iso7816_transaction_t {

    uint32_t cmd_frame;

    uint32_t resp_frame;

    uint8_t  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

uint16_t FI_to_Fi(uint8_t 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

uint8_t DI_to_Di(uint8_t 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, int offset, unsigned ta_index,

        packet_info *pinfo _U_, proto_tree *tree)

{

    uint8_t     ta, FI, DI;

    uint16_t    Fi;

    uint8_t     Di;

    proto_item *ta_it;

    proto_tree *ta_tree;

    ta = tvb_get_uint8(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_uint8(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_uint8(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_)

{

    int         offset=0;

    uint8_t     init_char;

    unsigned    i=0;  /* loop index for TA(i)...TD(i) */

    proto_item *proto_it;

    proto_tree *proto_tr;

    uint8_t     tb, tc, td, k=0;

    int         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_uint8(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_uint8(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_uint8(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_uint8(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, &ei_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 int

dissect_iso7816_class(tvbuff_t *tvb, int offset,

        packet_info *pinfo _U_, proto_tree *tree)

{

    proto_item *class_item;

    proto_tree *class_tree;

    uint8_t     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_uint8(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 int

dissect_iso7816_params(uint8_t ins, tvbuff_t *tvb, int offset,

                 packet_info *pinfo _U_, proto_tree *tree)

{

    int         offset_start, p1_offset, p2_offset;

    proto_tree *params_tree;

    uint8_t     p1, p2;

    proto_item *p1_it = NULL, *p2_it = NULL;

    proto_tree *p1_tree = NULL, *p2_tree = NULL;

    proto_item *p1_p2_it = NULL;

    uint16_t    P1P2;

    uint32_t    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_uint8(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_uint8(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 int

dissect_iso7816_le(

        tvbuff_t *tvb, int 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 int

dissect_iso7816_cmd_apdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)

{

    iso7816_transaction_t *iso7816_trans = NULL;

    proto_item            *trans_ti = NULL;

    int                    ret;

    int                    offset = 0;

    uint8_t                ins;

    int                    body_len;

    uint8_t                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 */

        if (iso7816_trans) {

            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_uint8(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_uint8(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 int

dissect_iso7816_resp_apdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)

{

    iso7816_transaction_t *iso7816_trans;

    proto_item            *trans_ti = NULL;

    const char            *cmd_ins_str;

    int                    offset = 0;

    int                    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_)

{

    int         offset = 0;

    proto_item *tree_ti;

    proto_tree *iso7816_tree;

    bool        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, 8, NULL, 0x10, NULL, HFILL }

        },

        { &hf_iso7816_atr_next_tb_present,

            { "TB(i+1) present", "iso7816.atr.next_tb_present",

                FT_BOOLEAN, 8, NULL, 0x20, NULL, HFILL }

        },

        { &hf_iso7816_atr_next_tc_present,

            { "TC(i+1) present", "iso7816.atr.next_tc_present",

                FT_BOOLEAN, 8, NULL, 0x40, NULL, HFILL }

        },

        { &hf_iso7816_atr_next_td_present,

            { "TD(i+1) present", "iso7816.atr.next_td_present",

                FT_BOOLEAN, 8, 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, FRAMENUM_TYPE(FT_FRAMENUM_RESPONSE), 0x0,

                "The response to this command is in this frame", HFILL }

        },

        { &hf_iso7816_resp_to,

            { "Response To", "iso7816.resp_to",

                FT_FRAMENUM, BASE_NONE, FRAMENUM_TYPE(FT_FRAMENUM_REQUEST), 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 int *ett[] = {