/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young (eay@cryptsoft.com).
 * The implementation was written so as to conform with Netscapes SSL.
 *
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
 *
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    "This product includes cryptographic software written by
 *     Eric Young (eay@cryptsoft.com)"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
 *
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.] */

#include <openssl/pem.h>

#include <stdio.h>
#include <string.h>

#include <openssl/dh.h>
#include <openssl/err.h>
#include <openssl/evp.h>
#include <openssl/mem.h>
#include <openssl/obj.h>
#include <openssl/pkcs8.h>
#include <openssl/rand.h>
#include <openssl/x509.h>

EVP_PKEY *PEM_read_bio_PrivateKey(BIO *bp, EVP_PKEY **x, pem_password_cb *cb,
                                  void *u) {
  char *nm = NULL;
  const unsigned char *p = NULL;
  unsigned char *data = NULL;
  long len;
  EVP_PKEY *ret = NULL;

  if (!PEM_bytes_read_bio(&data, &len, &nm, PEM_STRING_EVP_PKEY, bp, cb, u)) {
    return NULL;
  }
  p = data;

  if (strcmp(nm, PEM_STRING_PKCS8INF) == 0) {
    PKCS8_PRIV_KEY_INFO *p8inf;
    p8inf = d2i_PKCS8_PRIV_KEY_INFO(NULL, &p, len);
    if (!p8inf) {
      goto p8err;
    }
    ret = EVP_PKCS82PKEY(p8inf);
    if (x) {
      if (*x) {
        EVP_PKEY_free((EVP_PKEY *)*x);
      }
      *x = ret;
    }
    PKCS8_PRIV_KEY_INFO_free(p8inf);
  } else if (strcmp(nm, PEM_STRING_PKCS8) == 0) {
    PKCS8_PRIV_KEY_INFO *p8inf;
    X509_SIG *p8;
    int klen;
    char psbuf[PEM_BUFSIZE];
    p8 = d2i_X509_SIG(NULL, &p, len);
    if (!p8) {
      goto p8err;
    }

    klen = 0;
    if (!cb) {
      cb = PEM_def_callback;
    }
    klen = cb(psbuf, PEM_BUFSIZE, 0, u);
    if (klen <= 0) {
      OPENSSL_PUT_ERROR(PEM, PEM_R_BAD_PASSWORD_READ);
      X509_SIG_free(p8);
      goto err;
    }
    p8inf = PKCS8_decrypt(p8, psbuf, klen);
    X509_SIG_free(p8);
    OPENSSL_cleanse(psbuf, klen);
    if (!p8inf) {
      goto p8err;
    }
    ret = EVP_PKCS82PKEY(p8inf);
    if (x) {
      if (*x) {
        EVP_PKEY_free((EVP_PKEY *)*x);
      }
      *x = ret;
    }
    PKCS8_PRIV_KEY_INFO_free(p8inf);
  } else if (strcmp(nm, PEM_STRING_RSA) == 0) {
    // TODO(davidben): d2i_PrivateKey parses PKCS#8 along with the
    // standalone format. This and the cases below probably should not
    // accept PKCS#8.
    ret = d2i_PrivateKey(EVP_PKEY_RSA, x, &p, len);
  } else if (strcmp(nm, PEM_STRING_EC) == 0) {
    ret = d2i_PrivateKey(EVP_PKEY_EC, x, &p, len);
  } else if (strcmp(nm, PEM_STRING_DSA) == 0) {
    ret = d2i_PrivateKey(EVP_PKEY_DSA, x, &p, len);
  }
p8err:
  if (ret == NULL) {
    OPENSSL_PUT_ERROR(PEM, ERR_R_ASN1_LIB);
  }

err:
  OPENSSL_free(nm);
  OPENSSL_free(data);
  return ret;
}

int PEM_write_bio_PrivateKey(BIO *bp, EVP_PKEY *x, const EVP_CIPHER *enc,
                             unsigned char *kstr, int klen, pem_password_cb *cb,
                             void *u) {
  return PEM_write_bio_PKCS8PrivateKey(bp, x, enc, (char *)kstr, klen, cb, u);
}

EVP_PKEY *PEM_read_PrivateKey(FILE *fp, EVP_PKEY **x, pem_password_cb *cb,
                              void *u) {
  BIO *b = BIO_new_fp(fp, BIO_NOCLOSE);
  if (b == NULL) {
    OPENSSL_PUT_ERROR(PEM, ERR_R_BUF_LIB);
    return NULL;
  }
  EVP_PKEY *ret = PEM_read_bio_PrivateKey(b, x, cb, u);
  BIO_free(b);
  return ret;
}

int PEM_write_PrivateKey(FILE *fp, EVP_PKEY *x, const EVP_CIPHER *enc,
                         unsigned char *kstr, int klen, pem_password_cb *cb,
                         void *u) {
  BIO *b = BIO_new_fp(fp, BIO_NOCLOSE);
  if (b == NULL) {
    OPENSSL_PUT_ERROR(PEM, ERR_R_BUF_LIB);
    return 0;
  }
  int ret = PEM_write_bio_PrivateKey(b, x, enc, kstr, klen, cb, u);
  BIO_free(b);
  return ret;
}