/*

 * PKCS15 emulation layer for EstEID card issued from December 2025.

 *

 * Copyright (C) 2025, Raul Metsma <raul@metsma.ee>

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * This library is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include <ctype.h>

#include <stdlib.h>

#include <string.h>

#include "common/compat_strlcpy.h"

#include "internal.h"

#include "opensc.h"

#include "pkcs15.h"

static int

is_fin_eid(sc_pkcs15_card_t *p15card)

{

  return p15card->card->type == SC_CARD_TYPE_FINEID_2022 ||

         p15card->card->type == SC_CARD_TYPE_FINEID_2025;

}

static int

sc_pkcs15emu_esteid2025_init(sc_pkcs15_card_t *p15card)

{

  sc_card_t *card = p15card->card;

  int r, i;

  size_t field_length = 0;

  sc_path_t tmppath;

  static const u8 prkey_id[2] = {0x01, 0x02};

  static const u8 pin_authid[3] = {1, 2, 3};

  if (is_fin_eid(p15card)) {

    u8 buf[SC_MAX_APDU_BUFFER_SIZE];

    const u8 *tag;

    size_t taglen;

    sc_format_path("5032", &tmppath);

    r = sc_select_file(card, &tmppath, NULL);

    LOG_TEST_RET(card->ctx, r, "Selecting CIA path failed");

    r = sc_read_binary(p15card->card, 4, buf, sizeof(buf), 0);

    LOG_TEST_RET(card->ctx, r, "Reading tokeninfo file failed");

    tag = sc_asn1_find_tag(card->ctx, buf, r, 0x04, &taglen);

    if (tag == NULL)

      LOG_TEST_RET(card->ctx, SC_ERROR_INVALID_CARD, "Finding document number tag failed");

    for (size_t j = 0; j < taglen; j++) {

      if (!isalnum(tag[j]))

        LOG_TEST_RET(card->ctx, SC_ERROR_INVALID_CARD, "Invalid character in document number");

    }

    free(p15card->tokeninfo->serial_number);

    p15card->tokeninfo->serial_number = malloc(taglen + 1);

    if (p15card->tokeninfo->serial_number == NULL)

      LOG_FUNC_RETURN(card->ctx, SC_ERROR_OUT_OF_MEMORY);

    p15card->tokeninfo->serial_number = memcpy(p15card->tokeninfo->serial_number, tag, taglen);

    p15card->tokeninfo->serial_number[taglen] = '\0';

  } else {

    u8 *buf;

    size_t buflen = 9;

    /* Read document number to be used as serial */

    sc_format_path("DFDD5007", &tmppath);

    r = sc_select_file(card, &tmppath, NULL);

    LOG_TEST_RET(card->ctx, r, "Selecting document number file failed");

    buf = malloc(buflen + 1);

    if (!buf)

      LOG_FUNC_RETURN(card->ctx, SC_ERROR_OUT_OF_MEMORY);

    r = sc_read_binary(card, 0, buf, buflen, 0);

    if (r < 0) {

      free(buf);

      LOG_TEST_GOTO_ERR(card->ctx, r, "Reading document number failed");

    }

    for (int j = 0; j < r; j++) {

      if (!isalnum(buf[j])) {

        free(buf);

        LOG_TEST_GOTO_ERR(card->ctx, SC_ERROR_INVALID_CARD, "Invalid character in document number");

      }

    }

    buf[r] = '\0';

    free(p15card->tokeninfo->serial_number);

    p15card->tokeninfo->serial_number = (char *)buf;

  }

  set_string(&p15card->tokeninfo->label, "ID-kaart");

  set_string(&p15card->tokeninfo->manufacturer_id, "Thales");

  p15card->tokeninfo->flags = SC_PKCS15_TOKEN_READONLY;

  /* add certificates */

  for (i = 0; i < 2; i++) {

    static const char *cert_names[2] = {"Isikutuvastus", "Allkirjastamine"};

    static const char *cert_paths[2][2] = {

        {"ADF1:3411", "ADF2:3421"},

        {"4331",   "5016:4332"},

    };

    struct sc_pkcs15_cert_info cert_info = {

        .id = {.len = 1, .value[0] = prkey_id[i]}

     };

    struct sc_pkcs15_object cert_obj = {0};

    strlcpy(cert_obj.label, cert_names[i], sizeof(cert_obj.label));

    sc_format_path(cert_paths[is_fin_eid(p15card)][i], &cert_info.path);

    r = sc_pkcs15emu_add_x509_cert(p15card, &cert_obj, &cert_info);

    LOG_TEST_GOTO_ERR(card->ctx, r, "Could not add cert object");

    if (i != 0)

      continue;

    sc_pkcs15_cert_t *cert = NULL;

    r = sc_pkcs15_read_certificate(p15card, &cert_info, 0, &cert);

    LOG_TEST_GOTO_ERR(card->ctx, r, "Could not read authentication certificate");

    if (cert->key->algorithm == SC_ALGORITHM_EC)

      field_length = cert->key->u.ec.params.field_length;

    static const struct sc_object_id cn_oid = {

        {2, 5, 4, 3, -1}

    };

    u8 *cn_name = NULL;

    size_t cn_len = 0;

    r = sc_pkcs15_get_name_from_dn(card->ctx, cert->subject, cert->subject_len, &cn_oid, &cn_name, &cn_len);

    sc_pkcs15_free_certificate(cert);

    LOG_TEST_GOTO_ERR(card->ctx, r, "Could not read authentication certificate");

    if (cn_len > 0) {

      char *token_name = (char *)realloc(cn_name, cn_len + 1);

      if (token_name) {

        token_name[cn_len] = '\0';

        free(p15card->tokeninfo->label);

        p15card->tokeninfo->label = token_name;

      } else

        free(cn_name);

    }

  }

  /* add pins */

  for (i = 0; i < 3; i++) {

    static const char *pin_names[3] = {"PIN1", "PIN2", "PUK"};

    static const size_t pin_min[2][3] = {

        {4, 5, 8},

        {4, 6, 8},

    };

    static const int pin_ref[2][3] = {

        {0x81, 0x82, 0x83},

        {0x11, 0x82, 0x83},

    };

    static const unsigned int pin_flags[2][3] = {

        {SC_PKCS15_PIN_FLAG_NEEDS_PADDING | SC_PKCS15_PIN_TYPE_FLAGS_PIN_LOCAL,

          SC_PKCS15_PIN_FLAG_NEEDS_PADDING | SC_PKCS15_PIN_TYPE_FLAGS_PIN_LOCAL,

          SC_PKCS15_PIN_FLAG_NEEDS_PADDING | SC_PKCS15_PIN_TYPE_FLAGS_PUK_LOCAL},

        {SC_PKCS15_PIN_FLAG_NEEDS_PADDING | SC_PKCS15_PIN_TYPE_FLAGS_PIN_GLOBAL,

          SC_PKCS15_PIN_FLAG_NEEDS_PADDING | SC_PKCS15_PIN_TYPE_FLAGS_PIN_LOCAL,

          SC_PKCS15_PIN_FLAG_NEEDS_PADDING | SC_PKCS15_PIN_TYPE_FLAGS_PUK_LOCAL},

    };

    struct sc_pkcs15_auth_info pin_info = {

        .auth_id = {.len = 1, .value[0] = pin_authid[i]},

        .auth_type = SC_PKCS15_PIN_AUTH_TYPE_PIN,

        .attrs = {

            .pin = {

                .reference = pin_ref[is_fin_eid(p15card)][i],

                .flags = pin_flags[is_fin_eid(p15card)][i],

                .type = SC_PKCS15_PIN_TYPE_ASCII_NUMERIC,

                .min_length = pin_min[is_fin_eid(p15card)][i],

                .stored_length = 12,

                .max_length = 12,

                .pad_char = 0x00}},

        .tries_left = 3,

        .max_tries = 3

          };

    struct sc_pkcs15_object pin_obj = {.flags = pin_flags[is_fin_eid(p15card)][i]};

    strlcpy(pin_obj.label, pin_names[i], sizeof(pin_obj.label));

    /* Link normal PINs with PUK */

    if (i < 2) {

      pin_obj.auth_id.len = 1;

      pin_obj.auth_id.value[0] = 3;

    }

    r = sc_pkcs15emu_add_pin_obj(p15card, &pin_obj, &pin_info);

    LOG_TEST_GOTO_ERR(card->ctx, r, "Could not add pin object");

  }

  // trigger PIN counter refresh via pin_cmd

  struct sc_pkcs15_object *objs[3];

  r = sc_pkcs15_get_objects(p15card, SC_PKCS15_TYPE_AUTH, objs, 3);

  if (r != 3) {

    sc_log(card->ctx, "Can not get auth objects");

    goto err;

  }

  for (i = 0; i < r; i++) {

    r = sc_pkcs15_get_pin_info(p15card, objs[i]);

    LOG_TEST_GOTO_ERR(card->ctx, r, "Could not get pin object");

  }

  /* add private keys */

  for (i = 0; i < 2; i++) {

    static const u8 prkey_ref[2][2] = {

        {0x01, 0x05},

        {0x01, 0x02},

    };

    static const char *prkey_name[2] = {"Isikutuvastus", "Allkirjastamine"};

    static const unsigned int prkey_usage[2] = {SC_PKCS15_PRKEY_USAGE_SIGN | SC_PKCS15_PRKEY_USAGE_DERIVE,

        SC_PKCS15_PRKEY_USAGE_NONREPUDIATION};

    static const int prkey_consent[2] = {0, 1};

    struct sc_pkcs15_prkey_info prkey_info = {

        .id = {.len = 1, .value[0] = prkey_id[i]},

        .native = 1,

        .key_reference = prkey_ref[is_fin_eid(p15card)][i],

        .field_length = field_length,

        .usage = prkey_usage[i]

           };

    struct sc_pkcs15_object prkey_obj = {

        .auth_id = {.len = 1, .value[0] = pin_authid[i]},

        .user_consent = prkey_consent[i],

        .flags = SC_PKCS15_CO_FLAG_PRIVATE

      };

    strlcpy(prkey_obj.label, prkey_name[i], sizeof(prkey_obj.label));

    r = sc_pkcs15emu_add_ec_prkey(p15card, &prkey_obj, &prkey_info);

    LOG_TEST_GOTO_ERR(card->ctx, r, "Could not add private key object");

  }

  return SC_SUCCESS;

err:

  sc_pkcs15_card_clear(p15card);

  LOG_FUNC_RETURN(card->ctx, SC_ERROR_INTERNAL);

}

int

sc_pkcs15emu_esteid2025_init_ex(sc_pkcs15_card_t *p15card, struct sc_aid *aid)

{

  if (p15card->card->type == SC_CARD_TYPE_ESTEID_2025 || is_fin_eid(p15card))

    return sc_pkcs15emu_esteid2025_init(p15card);

  return SC_ERROR_WRONG_CARD;

}