// Copyright 2006-2016 The OpenSSL Project Authors. All Rights Reserved.

//

// Licensed under the Apache License, Version 2.0 (the "License");

// you may not use this file except in compliance with the License.

// You may obtain a copy of the License at

//

//     https://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software

// distributed under the License is distributed on an "AS IS" BASIS,

// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

// See the License for the specific language governing permissions and

// limitations under the License.

#include <openssl/evp.h>

#include <openssl/bio.h>

#include <openssl/bn.h>

#include <openssl/dsa.h>

#include <openssl/ec.h>

#include <openssl/ec_key.h>

#include <openssl/mem.h>

#include <openssl/rsa.h>

#include "../internal.h"

using namespace bssl;

static int print_hex(BIO *bp, const uint8_t *data, size_t len, int off) {

  for (size_t i = 0; i < len; i++) {

    if ((i % 15) == 0) {

      if (BIO_puts(bp, "\n") <= 0 ||  //

          !BIO_indent(bp, off + 4, 128)) {

        return 0;

      }

    }

    if (BIO_printf(bp, "%02x%s", data[i], (i + 1 == len) ? "" : ":") <= 0) {

      return 0;

    }

  }

  if (BIO_write(bp, "\n", 1) <= 0) {

    return 0;

  }

  return 1;

}

static int bn_print(BIO *bp, const char *name, const BIGNUM *num, int off) {

  if (num == nullptr) {

    return 1;

  }

  if (!BIO_indent(bp, off, 128)) {

    return 0;

  }

  if (BN_is_zero(num)) {

    if (BIO_printf(bp, "%s 0\n", name) <= 0) {

      return 0;

    }

    return 1;

  }

  uint64_t u64;

  if (BN_get_u64(num, &u64)) {

    const char *neg = BN_is_negative(num) ? "-" : "";

    return BIO_printf(bp, "%s %s%" PRIu64 " (%s0x%" PRIx64 ")\n", name, neg,

                      u64, neg, u64) > 0;

  }

  if (BIO_printf(bp, "%s%s", name,

                 (BN_is_negative(num)) ? " (Negative)" : "") <= 0) {

    return 0;

  }

  // Print `num` in hex, adding a leading zero, as in ASN.1, if the high bit

  // is set.

  //

  // TODO(davidben): Do we need to do this? We already print "(Negative)" above

  // and negative values are never valid in keys anyway.

  size_t len = BN_num_bytes(num);

  uint8_t *buf = reinterpret_cast<uint8_t *>(OPENSSL_malloc(len + 1));

  if (buf == nullptr) {

    return 0;

  }

  buf[0] = 0;

  BN_bn2bin(num, buf + 1);

  int ret;

  if (len > 0 && (buf[1] & 0x80) != 0) {

    // Print the whole buffer.

    ret = print_hex(bp, buf, len + 1, off);

  } else {

    // Skip the leading zero.

    ret = print_hex(bp, buf + 1, len, off);

  }

  OPENSSL_free(buf);

  return ret;

}

// RSA keys.

static int do_rsa_print(BIO *out, const RSA *rsa, int off,

                        int include_private) {

  int mod_len = 0;

  if (RSA_get0_n(rsa) != nullptr) {

    mod_len = RSA_bits(rsa);

  }

  if (!BIO_indent(out, off, 128)) {

    return 0;

  }

  const char *s, *str;

  if (include_private && RSA_get0_d(rsa) != nullptr) {

    if (BIO_printf(out, "Private-Key: (%d bit)\n", mod_len) <= 0) {

      return 0;

    }

    str = "modulus:";

    s = "publicExponent:";

  } else {

    if (BIO_printf(out, "Public-Key: (%d bit)\n", mod_len) <= 0) {

      return 0;

    }

    str = "Modulus:";

    s = "Exponent:";

  }

  if (!bn_print(out, str, RSA_get0_n(rsa), off) ||

      !bn_print(out, s, RSA_get0_e(rsa), off)) {

    return 0;

  }

  if (include_private) {

    if (!bn_print(out, "privateExponent:", RSA_get0_d(rsa), off) ||

        !bn_print(out, "prime1:", RSA_get0_p(rsa), off) ||

        !bn_print(out, "prime2:", RSA_get0_q(rsa), off) ||

        !bn_print(out, "exponent1:", RSA_get0_dmp1(rsa), off) ||

        !bn_print(out, "exponent2:", RSA_get0_dmq1(rsa), off) ||

        !bn_print(out, "coefficient:", RSA_get0_iqmp(rsa), off)) {

      return 0;

    }

  }

  return 1;

}

static int rsa_pub_print(BIO *bp, const EVP_PKEY *pkey, int indent) {

  return do_rsa_print(bp, EVP_PKEY_get0_RSA(pkey), indent, 0);

}

static int rsa_priv_print(BIO *bp, const EVP_PKEY *pkey, int indent) {

  return do_rsa_print(bp, EVP_PKEY_get0_RSA(pkey), indent, 1);

}

// EC keys.

static int do_EC_KEY_print(BIO *bp, const EC_KEY *x, int off, int ktype) {

  const EC_GROUP *group;

  if (x == nullptr || (group = EC_KEY_get0_group(x)) == nullptr) {

    OPENSSL_PUT_ERROR(EVP, ERR_R_PASSED_NULL_PARAMETER);

    return 0;

  }

  const char *ecstr;

  if (ktype == 2) {

    ecstr = "Private-Key";

  } else if (ktype == 1) {

    ecstr = "Public-Key";

  } else {

    ecstr = "ECDSA-Parameters";

  }

  if (!BIO_indent(bp, off, 128)) {

    return 0;

  }

  int curve_name = EC_GROUP_get_curve_name(group);

  if (BIO_printf(bp, "%s: (%s)\n", ecstr,

                 curve_name == NID_undef

                     ? "unknown curve"

                     : EC_curve_nid2nist(curve_name)) <= 0) {

    return 0;

  }

  if (ktype == 2) {

    const BIGNUM *priv_key = EC_KEY_get0_private_key(x);

    if (priv_key != nullptr &&  //

        !bn_print(bp, "priv:", priv_key, off)) {

      return 0;

    }

  }

  if (ktype > 0 && EC_KEY_get0_public_key(x) != nullptr) {

    uint8_t *pub = nullptr;

    size_t pub_len = EC_KEY_key2buf(x, EC_KEY_get_conv_form(x), &pub, nullptr);

    if (pub_len == 0) {

      return 0;

    }

    int ret = BIO_indent(bp, off, 128) &&  //

              BIO_puts(bp, "pub:") > 0 &&  //

              print_hex(bp, pub, pub_len, off);

    OPENSSL_free(pub);

    if (!ret) {

      return 0;

    }

  }

  return 1;

}

static int eckey_param_print(BIO *bp, const EVP_PKEY *pkey, int indent) {

  return do_EC_KEY_print(bp, EVP_PKEY_get0_EC_KEY(pkey), indent, 0);

}

static int eckey_pub_print(BIO *bp, const EVP_PKEY *pkey, int indent) {

  return do_EC_KEY_print(bp, EVP_PKEY_get0_EC_KEY(pkey), indent, 1);

}

static int eckey_priv_print(BIO *bp, const EVP_PKEY *pkey, int indent) {

  return do_EC_KEY_print(bp, EVP_PKEY_get0_EC_KEY(pkey), indent, 2);

}

typedef struct {

  int type;

  int (*pub_print)(BIO *out, const EVP_PKEY *pkey, int indent);

  int (*priv_print)(BIO *out, const EVP_PKEY *pkey, int indent);

  int (*param_print)(BIO *out, const EVP_PKEY *pkey, int indent);

} EVP_PKEY_PRINT_METHOD;

static const EVP_PKEY_PRINT_METHOD kPrintMethods[] = {

    {

        EVP_PKEY_RSA,

        rsa_pub_print,

        rsa_priv_print,

        /*param_print=*/nullptr,

    },

    {

        EVP_PKEY_EC,

        eckey_pub_print,

        eckey_priv_print,

        eckey_param_print,

    },

};

static const EVP_PKEY_PRINT_METHOD *find_method(int type) {

  for (const auto &p : kPrintMethods) {

    if (p.type == type) {

      return &p;

    }

  }

  return nullptr;

}

static int print_unsupported(BIO *out, const EVP_PKEY *pkey, int indent,

                             const char *kstr) {

  BIO_indent(out, indent, 128);

  BIO_printf(out, "%s algorithm unsupported\n", kstr);

  return 1;

}

int EVP_PKEY_print_public(BIO *out, const EVP_PKEY *pkey, int indent,

                          ASN1_PCTX *pctx) {

  const EVP_PKEY_PRINT_METHOD *method = find_method(EVP_PKEY_id(pkey));

  if (method != nullptr && method->pub_print != nullptr) {

    return method->pub_print(out, pkey, indent);

  }

  return print_unsupported(out, pkey, indent, "Public Key");

}

int EVP_PKEY_print_private(BIO *out, const EVP_PKEY *pkey, int indent,

                           ASN1_PCTX *pctx) {

  const EVP_PKEY_PRINT_METHOD *method = find_method(EVP_PKEY_id(pkey));

  if (method != nullptr && method->priv_print != nullptr) {

    return method->priv_print(out, pkey, indent);

  }

  return print_unsupported(out, pkey, indent, "Private Key");

}

int EVP_PKEY_print_params(BIO *out, const EVP_PKEY *pkey, int indent,

                          ASN1_PCTX *pctx) {

  const EVP_PKEY_PRINT_METHOD *method = find_method(EVP_PKEY_id(pkey));

  if (method != nullptr && method->param_print != nullptr) {

    return method->param_print(out, pkey, indent);

  }

  return print_unsupported(out, pkey, indent, "Parameters");

}