text: /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
   * project 1999-2004.
   */
  /* ====================================================================
   * Copyright (c) 1999 The OpenSSL Project.  All rights reserved.
   *
   * 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 above 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 acknowledgment:
   *    "This product includes software developed by the OpenSSL Project
   *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
   *
   * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
   *    endorse or promote products derived from this software without
   *    prior written permission. For written permission, please contact
   *    licensing@OpenSSL.org.
   *
   * 5. Products derived from this software may not be called "OpenSSL"
   *    nor may "OpenSSL" appear in their names without prior written
   *    permission of the OpenSSL Project.
   *
   * 6. Redistributions of any form whatsoever must retain the following
   *    acknowledgment:
   *    "This product includes software developed by the OpenSSL Project
   *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
   *
   * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
   * EXPRESSED 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 OpenSSL PROJECT OR
   * ITS 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.
   * ====================================================================
   *
   * This product includes cryptographic software written by Eric Young
   * (eay@cryptsoft.com).  This product includes software written by Tim
   * Hudson (tjh@cryptsoft.com). */
  
  #include <openssl/pkcs8.h>
  
  #include <limits.h>
  #include <string.h>
  
  #include <openssl/bytestring.h>
  #include <openssl/cipher.h>
  #include <openssl/err.h>
  #include <openssl/mem.h>
  #include <openssl/nid.h>
  #include <openssl/rand.h>
  
  #include "internal.h"
  #include "../internal.h"
  
  
  // 1.2.840.113549.1.5.12
  static const uint8_t kPBKDF2[] = {0x2a, 0x86, 0x48, 0x86, 0xf7,
                                    0x0d, 0x01, 0x05, 0x0c};
  
  // 1.2.840.113549.1.5.13
  static const uint8_t kPBES2[] = {0x2a, 0x86, 0x48, 0x86, 0xf7,
                                   0x0d, 0x01, 0x05, 0x0d};
  
  // 1.2.840.113549.2.7
  static const uint8_t kHMACWithSHA1[] = {0x2a, 0x86, 0x48, 0x86,
                                          0xf7, 0x0d, 0x02, 0x07};
  
  static const struct {
    uint8_t oid[9];
    uint8_t oid_len;
    int nid;
    const EVP_CIPHER *(*cipher_func)(void);
  } kCipherOIDs[] = {
      // 1.2.840.113549.3.2
      {{0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x03, 0x02},
       8,
       NID_rc2_cbc,
       &EVP_rc2_cbc},
      // 1.2.840.113549.3.7
      {{0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x03, 0x07},
       8,
       NID_des_ede3_cbc,
       &EVP_des_ede3_cbc},
      // 2.16.840.1.101.3.4.1.2
      {{0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x01, 0x02},
       9,
       NID_aes_128_cbc,
       &EVP_aes_128_cbc},
      // 2.16.840.1.101.3.4.1.22
      {{0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x01, 0x16},
       9,
       NID_aes_192_cbc,
       &EVP_aes_192_cbc},
      // 2.16.840.1.101.3.4.1.42
      {{0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x01, 0x2a},
       9,
       NID_aes_256_cbc,
       &EVP_aes_256_cbc},
  };
  
  static const EVP_CIPHER *cbs_to_cipher(const CBS *cbs) {
    for (size_t i = 0; i < OPENSSL_ARRAY_SIZE(kCipherOIDs); i++) {
      if (CBS_mem_equal(cbs, kCipherOIDs[i].oid, kCipherOIDs[i].oid_len)) {
        return kCipherOIDs[i].cipher_func();
      }
    }
  
    return NULL;
  }
  
  static int add_cipher_oid(CBB *out, int nid) {
    for (size_t i = 0; i < OPENSSL_ARRAY_SIZE(kCipherOIDs); i++) {
      if (kCipherOIDs[i].nid == nid) {
        CBB child;
        return CBB_add_asn1(out, &child, CBS_ASN1_OBJECT) &&
               CBB_add_bytes(&child, kCipherOIDs[i].oid,
                             kCipherOIDs[i].oid_len) &&
               CBB_flush(out);
      }
    }
  
    OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_UNSUPPORTED_CIPHER);
    return 0;
  }
  
  static int pkcs5_pbe2_cipher_init(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
                                    unsigned iterations, const char *pass,
                                    size_t pass_len, const uint8_t *salt,
                                    size_t salt_len, const uint8_t *iv,
                                    size_t iv_len, int enc) {
    if (iv_len != EVP_CIPHER_iv_length(cipher)) {
      OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_ERROR_SETTING_CIPHER_PARAMS);
      return 0;
    }
  
    uint8_t key[EVP_MAX_KEY_LENGTH];
    int ret = PKCS5_PBKDF2_HMAC_SHA1(pass, pass_len, salt, salt_len, iterations,
                                     EVP_CIPHER_key_length(cipher), key) &&
              EVP_CipherInit_ex(ctx, cipher, NULL /* engine */, key, iv, enc);
    OPENSSL_cleanse(key, EVP_MAX_KEY_LENGTH);
    return ret;
  }
  
  int PKCS5_pbe2_encrypt_init(CBB *out, EVP_CIPHER_CTX *ctx,
                              const EVP_CIPHER *cipher, unsigned iterations,
                              const char *pass, size_t pass_len,
                              const uint8_t *salt, size_t salt_len) {
    int cipher_nid = EVP_CIPHER_nid(cipher);
    if (cipher_nid == NID_undef) {
      OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_CIPHER_HAS_NO_OBJECT_IDENTIFIER);
      return 0;
    }
  
    // Generate a random IV.
    uint8_t iv[EVP_MAX_IV_LENGTH];
    if (!RAND_bytes(iv, EVP_CIPHER_iv_length(cipher))) {
      return 0;
    }
  
    // See RFC 2898, appendix A.
    CBB algorithm, oid, param, kdf, kdf_oid, kdf_param, salt_cbb, cipher_cbb,
        iv_cbb;
    if (!CBB_add_asn1(out, &algorithm, CBS_ASN1_SEQUENCE) ||
        !CBB_add_asn1(&algorithm, &oid, CBS_ASN1_OBJECT) ||
        !CBB_add_bytes(&oid, kPBES2, sizeof(kPBES2)) ||
        !CBB_add_asn1(&algorithm, &param, CBS_ASN1_SEQUENCE) ||
        !CBB_add_asn1(&param, &kdf, CBS_ASN1_SEQUENCE) ||
        !CBB_add_asn1(&kdf, &kdf_oid, CBS_ASN1_OBJECT) ||
        !CBB_add_bytes(&kdf_oid, kPBKDF2, sizeof(kPBKDF2)) ||
        !CBB_add_asn1(&kdf, &kdf_param, CBS_ASN1_SEQUENCE) ||
        !CBB_add_asn1(&kdf_param, &salt_cbb, CBS_ASN1_OCTETSTRING) ||
        !CBB_add_bytes(&salt_cbb, salt, salt_len) ||
        !CBB_add_asn1_uint64(&kdf_param, iterations) ||
        // Specify a key length for RC2.
        (cipher_nid == NID_rc2_cbc &&
         !CBB_add_asn1_uint64(&kdf_param, EVP_CIPHER_key_length(cipher))) ||
        // Omit the PRF. We use the default hmacWithSHA1.
        !CBB_add_asn1(&param, &cipher_cbb, CBS_ASN1_SEQUENCE) ||
        !add_cipher_oid(&cipher_cbb, cipher_nid) ||
        // RFC 2898 says RC2-CBC and RC5-CBC-Pad use a SEQUENCE with version and
        // IV, but OpenSSL always uses an OCTET STRING IV, so we do the same.
        !CBB_add_asn1(&cipher_cbb, &iv_cbb, CBS_ASN1_OCTETSTRING) ||
        !CBB_add_bytes(&iv_cbb, iv, EVP_CIPHER_iv_length(cipher)) ||
        !CBB_flush(out)) {
      return 0;
    }
  
    return pkcs5_pbe2_cipher_init(ctx, cipher, iterations, pass, pass_len, salt,
                                  salt_len, iv, EVP_CIPHER_iv_length(cipher),
                                  1 /* encrypt */);
  }
  
  int PKCS5_pbe2_decrypt_init(const struct pbe_suite *suite, EVP_CIPHER_CTX *ctx,
                              const char *pass, size_t pass_len, CBS *param) {
    CBS pbe_param, kdf, kdf_obj, enc_scheme, enc_obj;
    if (!CBS_get_asn1(param, &pbe_param, CBS_ASN1_SEQUENCE) ||
        CBS_len(param) != 0 ||
        !CBS_get_asn1(&pbe_param, &kdf, CBS_ASN1_SEQUENCE) ||
        !CBS_get_asn1(&pbe_param, &enc_scheme, CBS_ASN1_SEQUENCE) ||
        CBS_len(&pbe_param) != 0 ||
        !CBS_get_asn1(&kdf, &kdf_obj, CBS_ASN1_OBJECT) ||
        !CBS_get_asn1(&enc_scheme, &enc_obj, CBS_ASN1_OBJECT)) {
      OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_DECODE_ERROR);
      return 0;
    }
  
    // Only PBKDF2 is supported.
    if (!CBS_mem_equal(&kdf_obj, kPBKDF2, sizeof(kPBKDF2))) {
      OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_UNSUPPORTED_KEY_DERIVATION_FUNCTION);
      return 0;
    }
  
    // See if we recognise the encryption algorithm.
    const EVP_CIPHER *cipher = cbs_to_cipher(&enc_obj);
    if (cipher == NULL) {
      OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_UNSUPPORTED_CIPHER);
      return 0;
    }
  
    // Parse the KDF parameters. See RFC 8018, appendix A.2.
    CBS pbkdf2_params, salt;
    uint64_t iterations;
    if (!CBS_get_asn1(&kdf, &pbkdf2_params, CBS_ASN1_SEQUENCE) ||
        CBS_len(&kdf) != 0 ||
        !CBS_get_asn1(&pbkdf2_params, &salt, CBS_ASN1_OCTETSTRING) ||
        !CBS_get_asn1_uint64(&pbkdf2_params, &iterations)) {
      OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_DECODE_ERROR);
      return 0;
    }
  
    if (iterations == 0 || iterations > UINT_MAX) {
      OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_ITERATION_COUNT);
      return 0;
    }
  
    // The optional keyLength parameter, if present, must match the key length of
    // the cipher.
    if (CBS_peek_asn1_tag(&pbkdf2_params, CBS_ASN1_INTEGER)) {
      uint64_t key_len;
      if (!CBS_get_asn1_uint64(&pbkdf2_params, &key_len)) {
        OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_DECODE_ERROR);
        return 0;
      }
  
      if (key_len != EVP_CIPHER_key_length(cipher)) {
        OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_UNSUPPORTED_KEYLENGTH);
        return 0;
      }
    }
  
    if (CBS_len(&pbkdf2_params) != 0) {
      CBS alg_id, prf;
      if (!CBS_get_asn1(&pbkdf2_params, &alg_id, CBS_ASN1_SEQUENCE) ||
          !CBS_get_asn1(&alg_id, &prf, CBS_ASN1_OBJECT) ||
          CBS_len(&pbkdf2_params) != 0) {
        OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_DECODE_ERROR);
        return 0;
      }
  
      // We only support hmacWithSHA1. It is the DEFAULT, so DER requires it be
      // omitted, but we match OpenSSL in tolerating it being present.
      if (!CBS_mem_equal(&prf, kHMACWithSHA1, sizeof(kHMACWithSHA1))) {
        OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_UNSUPPORTED_PRF);
        return 0;
      }
  
      // hmacWithSHA1 has a NULL parameter.
      CBS null;
      if (!CBS_get_asn1(&alg_id, &null, CBS_ASN1_NULL) ||
          CBS_len(&null) != 0 ||
          CBS_len(&alg_id) != 0) {
        OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_DECODE_ERROR);
        return 0;
      }
    }
  
    // Parse the encryption scheme parameters. Note OpenSSL does not match the
    // specification. Per RFC 2898, this should depend on the encryption scheme.
    // In particular, RC2-CBC uses a SEQUENCE with version and IV. We align with
    // OpenSSL.
    CBS iv;
    if (!CBS_get_asn1(&enc_scheme, &iv, CBS_ASN1_OCTETSTRING) ||
        CBS_len(&enc_scheme) != 0) {
      OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_UNSUPPORTED_PRF);
      return 0;
    }
  
    return pkcs5_pbe2_cipher_init(ctx, cipher, (unsigned)iterations, pass,
                                  pass_len, CBS_data(&salt), CBS_len(&salt),
                                  CBS_data(&iv), CBS_len(&iv), 0 /* decrypt */);
  }
  