// Copyright 1995-2016 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/asn1.h>

#include <openssl/err.h>

#include <openssl/evp.h>

#include <openssl/obj.h>

#include <openssl/stack.h>

#include <openssl/x509.h>

#include "internal.h"

int X509v3_get_ext_count(const STACK_OF(X509_EXTENSION) *x) {

  if (x == nullptr) {

    return 0;

  }

  return (int)sk_X509_EXTENSION_num(x);

}

int X509v3_get_ext_by_NID(const STACK_OF(X509_EXTENSION) *x, int nid,

                          int lastpos) {

  const ASN1_OBJECT *obj = OBJ_nid2obj(nid);

  if (obj == nullptr) {

    return -1;

  }

  return X509v3_get_ext_by_OBJ(x, obj, lastpos);

}

int X509v3_get_ext_by_OBJ(const STACK_OF(X509_EXTENSION) *sk,

                          const ASN1_OBJECT *obj, int lastpos) {

  if (sk == nullptr) {

    return -1;

  }

  lastpos++;

  if (lastpos < 0) {

    lastpos = 0;

  }

  int n = (int)sk_X509_EXTENSION_num(sk);

  for (; lastpos < n; lastpos++) {

    const X509_EXTENSION *ex = sk_X509_EXTENSION_value(sk, lastpos);

    if (OBJ_cmp(ex->object, obj) == 0) {

      return lastpos;

    }

  }

  return -1;

}

int X509v3_get_ext_by_critical(const STACK_OF(X509_EXTENSION) *sk, int crit,

                               int lastpos) {

  if (sk == nullptr) {

    return -1;

  }

  lastpos++;

  if (lastpos < 0) {

    lastpos = 0;

  }

  crit = !!crit;

  int n = (int)sk_X509_EXTENSION_num(sk);

  for (; lastpos < n; lastpos++) {

    const X509_EXTENSION *ex = sk_X509_EXTENSION_value(sk, lastpos);

    if (X509_EXTENSION_get_critical(ex) == crit) {

      return lastpos;

    }

  }

  return -1;

}

X509_EXTENSION *X509v3_get_ext(const STACK_OF(X509_EXTENSION) *x, int loc) {

  if (x == nullptr || loc < 0 || sk_X509_EXTENSION_num(x) <= (size_t)loc) {

    return nullptr;

  } else {

    return sk_X509_EXTENSION_value(x, loc);

  }

}

X509_EXTENSION *X509v3_delete_ext(STACK_OF(X509_EXTENSION) *x, int loc) {

  X509_EXTENSION *ret;

  if (x == nullptr || loc < 0 || sk_X509_EXTENSION_num(x) <= (size_t)loc) {

    return nullptr;

  }

  ret = sk_X509_EXTENSION_delete(x, loc);

  return ret;

}

STACK_OF(X509_EXTENSION) *X509v3_add_ext(STACK_OF(X509_EXTENSION) **x,

                                         const X509_EXTENSION *ex, int loc) {

  X509_EXTENSION *new_ex = nullptr;

  STACK_OF(X509_EXTENSION) *sk = nullptr;

  int free_sk = 0, n;

  if (x == nullptr) {

    OPENSSL_PUT_ERROR(X509, ERR_R_PASSED_NULL_PARAMETER);

    goto err;

  }

  if (*x == nullptr) {

    if ((sk = sk_X509_EXTENSION_new_null()) == nullptr) {

      goto err;

    }

    free_sk = 1;

  } else {

    sk = *x;

  }

  n = (int)sk_X509_EXTENSION_num(sk);

  if (loc > n) {

    loc = n;

  } else if (loc < 0) {

    loc = n;

  }

  if ((new_ex = X509_EXTENSION_dup(ex)) == nullptr) {

    goto err;

  }

  if (!sk_X509_EXTENSION_insert(sk, new_ex, loc)) {

    goto err;

  }

  if (*x == nullptr) {

    *x = sk;

  }

  return sk;

err:

  X509_EXTENSION_free(new_ex);

  if (free_sk) {

    sk_X509_EXTENSION_free(sk);

  }

  return nullptr;

}

X509_EXTENSION *X509_EXTENSION_create_by_NID(X509_EXTENSION **ex, int nid,

                                             int crit,

                                             const ASN1_OCTET_STRING *data) {

  const ASN1_OBJECT *obj;

  X509_EXTENSION *ret;

  obj = OBJ_nid2obj(nid);

  if (obj == nullptr) {

    OPENSSL_PUT_ERROR(X509, X509_R_UNKNOWN_NID);

    return nullptr;

  }

  ret = X509_EXTENSION_create_by_OBJ(ex, obj, crit, data);

  return ret;

}

X509_EXTENSION *X509_EXTENSION_create_by_OBJ(X509_EXTENSION **ex,

                                             const ASN1_OBJECT *obj, int crit,

                                             const ASN1_OCTET_STRING *data) {

  X509_EXTENSION *ret;

  if ((ex == nullptr) || (*ex == nullptr)) {

    if ((ret = X509_EXTENSION_new()) == nullptr) {

      return nullptr;

    }

  } else {

    ret = *ex;

  }

  if (!X509_EXTENSION_set_object(ret, obj)) {

    goto err;

  }

  if (!X509_EXTENSION_set_critical(ret, crit)) {

    goto err;

  }

  if (!X509_EXTENSION_set_data(ret, data)) {

    goto err;

  }

  if ((ex != nullptr) && (*ex == nullptr)) {

    *ex = ret;

  }

  return ret;

err:

  if ((ex == nullptr) || (ret != *ex)) {

    X509_EXTENSION_free(ret);

  }

  return nullptr;

}

int X509_EXTENSION_set_object(X509_EXTENSION *ex, const ASN1_OBJECT *obj) {

  if ((ex == nullptr) || (obj == nullptr)) {

    return 0;

  }

  ASN1_OBJECT_free(ex->object);

  ex->object = OBJ_dup(obj);

  return ex->object != nullptr;

}

int X509_EXTENSION_set_critical(X509_EXTENSION *ex, int crit) {

  if (ex == nullptr) {

    return 0;

  }

  // The critical field is DEFAULT FALSE, so non-critical extensions should omit

  // the value.

  ex->critical = crit ? ASN1_BOOLEAN_TRUE : ASN1_BOOLEAN_NONE;

  return 1;

}

int X509_EXTENSION_set_data(X509_EXTENSION *ex, const ASN1_OCTET_STRING *data) {

  int i;

  if (ex == nullptr) {

    return 0;

  }

  i = ASN1_OCTET_STRING_set(ex->value, data->data, data->length);

  if (!i) {

    return 0;

  }

  return 1;

}

ASN1_OBJECT *X509_EXTENSION_get_object(const X509_EXTENSION *ex) {

  if (ex == nullptr) {

    return nullptr;

  }

  return ex->object;

}

ASN1_OCTET_STRING *X509_EXTENSION_get_data(const X509_EXTENSION *ex) {

  if (ex == nullptr) {

    return nullptr;

  }

  return ex->value;

}

int X509_EXTENSION_get_critical(const X509_EXTENSION *ex) {

  if (ex == nullptr) {

    return 0;

  }

  if (ex->critical > 0) {

    return 1;

  }

  return 0;

}