text: /*
   * Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
   *
   * Licensed under the Apache License 2.0 (the "License").  You may not use
   * this file except in compliance with the License.  You can obtain a copy
   * in the file LICENSE in the source distribution or at
   * https://www.openssl.org/source/license.html
   */
  
  #include <string.h>
  #include <stdio.h>
  #include <openssl/opensslconf.h>
  #include <openssl/core.h>
  #include <openssl/core_numbers.h>
  #include <openssl/core_names.h>
  #include <openssl/params.h>
  #include "prov/implementations.h"
  
  /* Functions provided by the core */
  static OSSL_core_gettable_params_fn *c_gettable_params = NULL;
  static OSSL_core_get_params_fn *c_get_params = NULL;
  
  /* Parameters we provide to the core */
  static const OSSL_PARAM deflt_param_types[] = {
      OSSL_PARAM_DEFN(OSSL_PROV_PARAM_NAME, OSSL_PARAM_UTF8_PTR, NULL, 0),
      OSSL_PARAM_DEFN(OSSL_PROV_PARAM_VERSION, OSSL_PARAM_UTF8_PTR, NULL, 0),
      OSSL_PARAM_DEFN(OSSL_PROV_PARAM_BUILDINFO, OSSL_PARAM_UTF8_PTR, NULL, 0),
      OSSL_PARAM_END
  };
  
  static const OSSL_PARAM *deflt_gettable_params(const OSSL_PROVIDER *prov)
  {
      return deflt_param_types;
  }
  
  static int deflt_get_params(const OSSL_PROVIDER *prov, OSSL_PARAM params[])
  {
      OSSL_PARAM *p;
  
      p = OSSL_PARAM_locate(params, OSSL_PROV_PARAM_NAME);
      if (p != NULL && !OSSL_PARAM_set_utf8_ptr(p, "OpenSSL Default Provider"))
          return 0;
      p = OSSL_PARAM_locate(params, OSSL_PROV_PARAM_VERSION);
      if (p != NULL && !OSSL_PARAM_set_utf8_ptr(p, OPENSSL_VERSION_STR))
          return 0;
      p = OSSL_PARAM_locate(params, OSSL_PROV_PARAM_BUILDINFO);
      if (p != NULL && !OSSL_PARAM_set_utf8_ptr(p, OPENSSL_FULL_VERSION_STR))
          return 0;
  
      return 1;
  }
  
  /*
   * For the algorithm names, we use the following formula for our primary
   * names:
   *
   *     ALGNAME[VERSION?][-SUBNAME[VERSION?]?][-SIZE?][-MODE?]
   *
   *     VERSION is only present if there are multiple versions of
   *     an alg (MD2, MD4, MD5).  It may be omitted if there is only
   *     one version (if a subsequent version is released in the future,
   *     we can always change the canonical name, and add the old name
   *     as an alias).
   *
   *     SUBNAME may be present where we are combining multiple
   *     algorithms together, e.g. MD5-SHA1.
   *
   *     SIZE is only present if multiple versions of an algorithm exist
   *     with different sizes (e.g. AES-128-CBC, AES-256-CBC)
   *
   *     MODE is only present where applicable.
   *
   * We add diverse other names where applicable, such as the names that
   * NIST uses, or that are used for ASN.1 OBJECT IDENTIFIERs, or names
   * we have used historically.
   *
   * Algorithm names are case insensitive, but we use all caps in our "canonical"
   * names for consistency.
   */
  static const OSSL_ALGORITHM deflt_digests[] = {
      /* Our primary name:NIST name[:our older names] */
      { "SHA1:SHA-1", "default=yes", sha1_functions },
      { "SHA2-224:SHA-224:SHA224", "default=yes", sha224_functions },
      { "SHA2-256:SHA-256:SHA256", "default=yes", sha256_functions },
      { "SHA2-384:SHA-384:SHA384", "default=yes", sha384_functions },
      { "SHA2-512:SHA-512:SHA512", "default=yes", sha512_functions },
      { "SHA2-512/224:SHA-512/224:SHA512-224", "default=yes",
        sha512_224_functions },
      { "SHA2-512/256:SHA-512/256:SHA512-256", "default=yes",
        sha512_256_functions },
  
      /* We agree with NIST here, so one name only */
      { "SHA3-224", "default=yes", sha3_224_functions },
      { "SHA3-256", "default=yes", sha3_256_functions },
      { "SHA3-384", "default=yes", sha3_384_functions },
      { "SHA3-512", "default=yes", sha3_512_functions },
  
      /*
       * KECCAK-KMAC-128 and KECCAK-KMAC-256 as hashes are mostly useful for
       * the KMAC-128 and KMAC-256.
       */
      { "KECCAK-KMAC-128:KECCAK-KMAC128", "default=yes", keccak_kmac_128_functions },
      { "KECCAK-KMAC-256:KECCAK-KMAC256", "default=yes", keccak_kmac_256_functions },
  
      /* Our primary name:NIST name */
      { "SHAKE-128:SHAKE128", "default=yes", shake_128_functions },
      { "SHAKE-256:SHAKE256", "default=yes", shake_256_functions },
  
  #ifndef OPENSSL_NO_BLAKE2
      /*
       * https://blake2.net/ doesn't specify size variants,
       * but mentions that Bouncy Castle uses the names
       * BLAKE2b-160, BLAKE2b-256, BLAKE2b-384, and BLAKE2b-512
       * If we assume that "2b" and "2s" are versions, that pattern
       * fits with ours.  We also add our historical names.
       */
      { "BLAKE2S-256:BLAKE2s256", "default=yes", blake2s256_functions },
      { "BLAKE2B-512:BLAKE2b512", "default=yes", blake2b512_functions },
  #endif /* OPENSSL_NO_BLAKE2 */
  
  #ifndef OPENSSL_NO_SM3
      { "SM3", "default=yes", sm3_functions },
  #endif /* OPENSSL_NO_SM3 */
  
  #ifndef OPENSSL_NO_MD5
      { "MD5", "default=yes", md5_functions },
      { "MD5-SHA1", "default=yes", md5_sha1_functions },
  #endif /* OPENSSL_NO_MD5 */
  
      { NULL, NULL, NULL }
  };
  
  static const OSSL_ALGORITHM deflt_ciphers[] = {
      { "AES-256-ECB", "default=yes", aes256ecb_functions },
      { "AES-192-ECB", "default=yes", aes192ecb_functions },
      { "AES-128-ECB", "default=yes", aes128ecb_functions },
      { "AES-256-CBC", "default=yes", aes256cbc_functions },
      { "AES-192-CBC", "default=yes", aes192cbc_functions },
      { "AES-128-CBC", "default=yes", aes128cbc_functions },
      { "AES-256-OFB", "default=yes", aes256ofb_functions },
      { "AES-192-OFB", "default=yes", aes192ofb_functions },
      { "AES-128-OFB", "default=yes", aes128ofb_functions },
      { "AES-256-CFB", "default=yes", aes256cfb_functions },
      { "AES-192-CFB", "default=yes", aes192cfb_functions },
      { "AES-128-CFB", "default=yes", aes128cfb_functions },
      { "AES-256-CFB1", "default=yes", aes256cfb1_functions },
      { "AES-192-CFB1", "default=yes", aes192cfb1_functions },
      { "AES-128-CFB1", "default=yes", aes128cfb1_functions },
      { "AES-256-CFB8", "default=yes", aes256cfb8_functions },
      { "AES-192-CFB8", "default=yes", aes192cfb8_functions },
      { "AES-128-CFB8", "default=yes", aes128cfb8_functions },
      { "AES-256-CTR", "default=yes", aes256ctr_functions },
      { "AES-192-CTR", "default=yes", aes192ctr_functions },
      { "AES-128-CTR", "default=yes", aes128ctr_functions },
      { "AES-256-XTS", "default=yes", aes256xts_functions },
      { "AES-128-XTS", "default=yes", aes128xts_functions },
  #ifndef OPENSSL_NO_OCB
      { "AES-256-OCB", "default=yes", aes256ocb_functions },
      { "AES-192-OCB", "default=yes", aes192ocb_functions },
      { "AES-128-OCB", "default=yes", aes128ocb_functions },
  #endif /* OPENSSL_NO_OCB */
  #ifndef OPENSSL_NO_SIV
      { "AES-128-SIV", "default=yes", aes128siv_functions },
      { "AES-192-SIV", "default=yes", aes192siv_functions },
      { "AES-256-SIV", "default=yes", aes256siv_functions },
  #endif /* OPENSSL_NO_SIV */
      { "AES-256-GCM:id-aes256-GCM", "default=yes", aes256gcm_functions },
      { "AES-192-GCM:id-aes192-GCM", "default=yes", aes192gcm_functions },
      { "AES-128-GCM:id-aes128-GCM", "default=yes", aes128gcm_functions },
      { "AES-256-CCM:id-aes256-CCM", "default=yes", aes256ccm_functions },
      { "AES-192-CCM:id-aes192-CCM", "default=yes", aes192ccm_functions },
      { "AES-128-CCM:id-aes128-CCM", "default=yes", aes128ccm_functions },
      { "AES-256-WRAP:id-aes256-wrap:AES256-WRAP", "default=yes",
        aes256wrap_functions },
      { "AES-192-WRAP:id-aes192-wrap:AES192-WRAP", "default=yes",
        aes192wrap_functions },
      { "AES-128-WRAP:id-aes128-wrap:AES128-WRAP", "default=yes",
        aes128wrap_functions },
      { "AES-256-WRAP-PAD:id-aes256-wrap-pad:AES256-WRAP-PAD", "default=yes",
        aes256wrappad_functions },
      { "AES-192-WRAP-PAD:id-aes192-wrap-pad:AES192-WRAP-PAD", "default=yes",
        aes192wrappad_functions },
      { "AES-128-WRAP-PAD:id-aes128-wrap-pad:AES128-WRAP-PAD", "default=yes",
        aes128wrappad_functions },
  #ifndef OPENSSL_NO_ARIA
      { "ARIA-256-GCM", "default=yes", aria256gcm_functions },
      { "ARIA-192-GCM", "default=yes", aria192gcm_functions },
      { "ARIA-128-GCM", "default=yes", aria128gcm_functions },
      { "ARIA-256-CCM", "default=yes", aria256ccm_functions },
      { "ARIA-192-CCM", "default=yes", aria192ccm_functions },
      { "ARIA-128-CCM", "default=yes", aria128ccm_functions },
      { "ARIA-256-ECB", "default=yes", aria256ecb_functions },
      { "ARIA-192-ECB", "default=yes", aria192ecb_functions },
      { "ARIA-128-ECB", "default=yes", aria128ecb_functions },
      { "ARIA-256-CBC:ARIA256", "default=yes", aria256cbc_functions },
      { "ARIA-192-CBC:ARIA192", "default=yes", aria192cbc_functions },
      { "ARIA-128-CBC:ARIA128", "default=yes", aria128cbc_functions },
      { "ARIA-256-OFB", "default=yes", aria256ofb_functions },
      { "ARIA-192-OFB", "default=yes", aria192ofb_functions },
      { "ARIA-128-OFB", "default=yes", aria128ofb_functions },
      { "ARIA-256-CFB", "default=yes", aria256cfb_functions },
      { "ARIA-192-CFB", "default=yes", aria192cfb_functions },
      { "ARIA-128-CFB", "default=yes", aria128cfb_functions },
      { "ARIA-256-CFB1", "default=yes", aria256cfb1_functions },
      { "ARIA-192-CFB1", "default=yes", aria192cfb1_functions },
      { "ARIA-128-CFB1", "default=yes", aria128cfb1_functions },
      { "ARIA-256-CFB8", "default=yes", aria256cfb8_functions },
      { "ARIA-192-CFB8", "default=yes", aria192cfb8_functions },
      { "ARIA-128-CFB8", "default=yes", aria128cfb8_functions },
      { "ARIA-256-CTR", "default=yes", aria256ctr_functions },
      { "ARIA-192-CTR", "default=yes", aria192ctr_functions },
      { "ARIA-128-CTR", "default=yes", aria128ctr_functions },
  #endif /* OPENSSL_NO_ARIA */
  #ifndef OPENSSL_NO_CAMELLIA
      { "CAMELLIA-256-ECB", "default=yes", camellia256ecb_functions },
      { "CAMELLIA-192-ECB", "default=yes", camellia192ecb_functions },
      { "CAMELLIA-128-ECB", "default=yes", camellia128ecb_functions },
      { "CAMELLIA-256-CBC:CAMELLIA256", "default=yes", camellia256cbc_functions },
      { "CAMELLIA-192-CBC:CAMELLIA192", "default=yes", camellia192cbc_functions },
      { "CAMELLIA-128-CBC:CAMELLIA128", "default=yes", camellia128cbc_functions },
      { "CAMELLIA-256-OFB", "default=yes", camellia256ofb_functions },
      { "CAMELLIA-192-OFB", "default=yes", camellia192ofb_functions },
      { "CAMELLIA-128-OFB", "default=yes", camellia128ofb_functions },
      { "CAMELLIA-256-CFB", "default=yes", camellia256cfb_functions },
      { "CAMELLIA-192-CFB", "default=yes", camellia192cfb_functions },
      { "CAMELLIA-128-CFB", "default=yes", camellia128cfb_functions },
      { "CAMELLIA-256-CFB1", "default=yes", camellia256cfb1_functions },
      { "CAMELLIA-192-CFB1", "default=yes", camellia192cfb1_functions },
      { "CAMELLIA-128-CFB1", "default=yes", camellia128cfb1_functions },
      { "CAMELLIA-256-CFB8", "default=yes", camellia256cfb8_functions },
      { "CAMELLIA-192-CFB8", "default=yes", camellia192cfb8_functions },
      { "CAMELLIA-128-CFB8", "default=yes", camellia128cfb8_functions },
      { "CAMELLIA-256-CTR", "default=yes", camellia256ctr_functions },
      { "CAMELLIA-192-CTR", "default=yes", camellia192ctr_functions },
      { "CAMELLIA-128-CTR", "default=yes", camellia128ctr_functions },
  #endif /* OPENSSL_NO_CAMELLIA */
  #ifndef OPENSSL_NO_DES
      { "DES-EDE3-ECB:DES-EDE3", "default=yes", tdes_ede3_ecb_functions },
      { "DES-EDE3-CBC:DES3", "default=yes", tdes_ede3_cbc_functions },
      { "DES-EDE3-OFB", "default=yes", tdes_ede3_ofb_functions },
      { "DES-EDE3-CFB", "default=yes", tdes_ede3_cfb_functions },
      { "DES-EDE3-CFB8", "default=yes", tdes_ede3_cfb8_functions },
      { "DES-EDE3-CFB1", "default=yes", tdes_ede3_cfb1_functions },
      { "DES-EDE-ECB:DES-EDE", "default=yes", tdes_ede2_ecb_functions },
      { "DES-EDE-CBC", "default=yes", tdes_ede2_cbc_functions },
      { "DES-EDE-OFB", "default=yes", tdes_ede2_ofb_functions },
      { "DES-EDE-CFB", "default=yes", tdes_ede2_cfb_functions },
      { "DESX-CBC:DESX", "default=yes", tdes_desx_cbc_functions },
      { "DES3-WRAP:id-smime-alg-CMS3DESwrap", "default=yes", tdes_wrap_cbc_functions },
      { "DES-ECB", "default=yes", des_ecb_functions },
      { "DES-CBC:DES", "default=yes", des_cbc_functions },
      { "DES-OFB", "default=yes", des_ofb64_functions },
      { "DES-CFB", "default=yes", des_cfb64_functions },
      { "DES-CFB1", "default=yes", des_cfb1_functions },
      { "DES-CFB8", "default=yes", des_cfb8_functions },
  #endif /* OPENSSL_NO_DES */
  #ifndef OPENSSL_NO_BF
      { "BF-ECB", "default=yes", blowfish128ecb_functions },
      { "BF-CBC:BF:BLOWFISH", "default=yes", blowfish128cbc_functions },
      { "BF-OFB", "default=yes", blowfish64ofb64_functions },
      { "BF-CFB", "default=yes", blowfish64cfb64_functions },
  #endif /* OPENSSL_NO_BF */
  #ifndef OPENSSL_NO_IDEA
      { "IDEA-ECB", "default=yes", idea128ecb_functions },
      { "IDEA-CBC:IDEA", "default=yes", idea128cbc_functions },
      { "IDEA-OFB:IDEA-OFB64", "default=yes", idea128ofb64_functions },
      { "IDEA-CFB:IDEA-CFB64", "default=yes", idea128cfb64_functions },
  #endif /* OPENSSL_NO_IDEA */
  #ifndef OPENSSL_NO_CAST
      { "CAST5-ECB", "default=yes", cast5128ecb_functions },
      { "CAST5-CBC:CAST-CBC:CAST", "default=yes", cast5128cbc_functions },
      { "CAST5-OFB", "default=yes", cast564ofb64_functions },
      { "CAST5-CFB", "default=yes", cast564cfb64_functions },
  #endif /* OPENSSL_NO_CAST */
  #ifndef OPENSSL_NO_SEED
      { "SEED-ECB", "default=yes", seed128ecb_functions },
      { "SEED-CBC:SEED", "default=yes", seed128cbc_functions },
      { "SEED-OFB:SEED-OFB128", "default=yes", seed128ofb128_functions },
      { "SEED-CFB:SEED-CFB128", "default=yes", seed128cfb128_functions },
  #endif /* OPENSSL_NO_SEED */
  #ifndef OPENSSL_NO_SM4
      { "SM4-ECB", "default=yes", sm4128ecb_functions },
      { "SM4-CBC:SM4", "default=yes", sm4128cbc_functions },
      { "SM4-CTR", "default=yes", sm4128ctr_functions },
      { "SM4-OFB:SM4-OFB128", "default=yes", sm4128ofb128_functions },
      { "SM4-CFB:SM4-CFB128", "default=yes", sm4128cfb128_functions },
  #endif /* OPENSSL_NO_SM4 */
  #ifndef OPENSSL_NO_RC4
      { "RC4", "default=yes", rc4128_functions },
      { "RC4-40", "default=yes", rc440_functions },
  # ifndef OPENSSL_NO_MD5
      { "RC4-HMAC-MD5", "default=yes", rc4_hmac_md5_functions },
  # endif /* OPENSSL_NO_MD5 */
  #endif /* OPENSSL_NO_RC4 */
  #ifndef OPENSSL_NO_RC5
      { "RC5-ECB", "default=yes", rc5128ecb_functions },
      { "RC5-CBC", "default=yes", rc5128cbc_functions },
      { "RC5-OFB", "default=yes", rc5128ofb64_functions },
      { "RC5-CFB", "default=yes", rc5128cfb64_functions },
  #endif /* OPENSSL_NO_RC5 */
  #ifndef OPENSSL_NO_RC2
      { "RC2-ECB", "default=yes", rc2128ecb_functions },
      { "RC2-CBC", "default=yes", rc2128cbc_functions },
      { "RC2-40-CBC", "default=yes", rc240cbc_functions },
      { "RC2-64-CBC", "default=yes", rc264cbc_functions },
      { "RC2-CFB", "default=yes", rc2128cfb128_functions },
      { "RC2-OFB", "default=yes", rc2128ofb128_functions },
  #endif /* OPENSSL_NO_RC2 */
  #ifndef OPENSSL_NO_CHACHA
      { "ChaCha20", "default=yes", chacha20_functions },
  # ifndef OPENSSL_NO_POLY1305
      { "ChaCha20-Poly1305", "default=yes", chacha20_poly1305_functions },
  # endif /* OPENSSL_NO_POLY1305 */
  #endif /* OPENSSL_NO_CHACHA */
      { NULL, NULL, NULL }
  };
  
  static const OSSL_ALGORITHM deflt_macs[] = {
  #ifndef OPENSSL_NO_BLAKE2
      { "BLAKE2BMAC", "default=yes", blake2bmac_functions },
      { "BLAKE2SMAC", "default=yes", blake2smac_functions },
  #endif
  #ifndef OPENSSL_NO_CMAC
      { "CMAC", "default=yes", cmac_functions },
  #endif
      { "GMAC", "default=yes", gmac_functions },
      { "HMAC", "default=yes", hmac_functions },
      { "KMAC-128:KMAC128", "default=yes", kmac128_functions },
      { "KMAC-256:KMAC256", "default=yes", kmac256_functions },
  #ifndef OPENSSL_NO_SIPHASH
      { "SIPHASH", "default=yes", siphash_functions },
  #endif
  #ifndef OPENSSL_NO_POLY1305
      { "POLY1305", "default=yes", poly1305_functions },
  #endif
      { NULL, NULL, NULL }
  };
  
  static const OSSL_ALGORITHM deflt_kdfs[] = {
      { "HKDF", "default=yes", kdf_hkdf_functions },
      { "SSKDF", "default=yes", kdf_sskdf_functions },
      { "PBKDF2", "default=yes", kdf_pbkdf2_functions },
      { "SSHKDF", "default=yes", kdf_sshkdf_functions },
      { "X963KDF", "default=yes", kdf_x963_kdf_functions },
      { "TLS1-PRF", "default=yes", kdf_tls1_prf_functions },
      { "KBKDF", "default=yes", kdf_kbkdf_functions },
  #ifndef OPENSSL_NO_CMS
      { "X942KDF", "default=yes", kdf_x942_kdf_functions },
  #endif
  #ifndef OPENSSL_NO_SCRYPT
      { "SCRYPT:id-scrypt", "default=yes", kdf_scrypt_functions },
  #endif
      { "KRB5KDF", "default=yes", kdf_krb5kdf_functions },
      { NULL, NULL, NULL }
  };
  
  static const OSSL_ALGORITHM deflt_keyexch[] = {
  #ifndef OPENSSL_NO_DH
      { "DH:dhKeyAgreement", "default=yes", dh_keyexch_functions },
  #endif
      { NULL, NULL, NULL }
  };
  
  static const OSSL_ALGORITHM deflt_signature[] = {
  #ifndef OPENSSL_NO_DSA
      { "DSA:dsaEncryption", "default=yes", dsa_signature_functions },
  #endif
      { NULL, NULL, NULL }
  };
  
  static const OSSL_ALGORITHM deflt_asym_cipher[] = {
      { "RSA:rsaEncryption", "default=yes", rsa_asym_cipher_functions },
      { NULL, NULL, NULL }
  };
  
  static const OSSL_ALGORITHM deflt_keymgmt[] = {
  #ifndef OPENSSL_NO_DH
      { "DH", "default=yes", dh_keymgmt_functions },
  #endif
  #ifndef OPENSSL_NO_DSA
      { "DSA", "default=yes", dsa_keymgmt_functions },
  #endif
      { "RSA", "default=yes", rsa_keymgmt_functions },
      { NULL, NULL, NULL }
  };
  
  static const OSSL_ALGORITHM *deflt_query(OSSL_PROVIDER *prov,
                                           int operation_id,
                                           int *no_cache)
  {
      *no_cache = 0;
      switch (operation_id) {
      case OSSL_OP_DIGEST:
          return deflt_digests;
      case OSSL_OP_CIPHER:
          return deflt_ciphers;
      case OSSL_OP_MAC:
          return deflt_macs;
      case OSSL_OP_KDF:
          return deflt_kdfs;
      case OSSL_OP_KEYMGMT:
          return deflt_keymgmt;
      case OSSL_OP_KEYEXCH:
          return deflt_keyexch;
      case OSSL_OP_SIGNATURE:
          return deflt_signature;
      case OSSL_OP_ASYM_CIPHER:
          return deflt_asym_cipher;
      }
      return NULL;
  }
  
  /* Functions we provide to the core */
  static const OSSL_DISPATCH deflt_dispatch_table[] = {
      { OSSL_FUNC_PROVIDER_GETTABLE_PARAMS, (void (*)(void))deflt_gettable_params },
      { OSSL_FUNC_PROVIDER_GET_PARAMS, (void (*)(void))deflt_get_params },
      { OSSL_FUNC_PROVIDER_QUERY_OPERATION, (void (*)(void))deflt_query },
      { 0, NULL }
  };
  
  OSSL_provider_init_fn ossl_default_provider_init;
  
  int ossl_default_provider_init(const OSSL_PROVIDER *provider,
                                 const OSSL_DISPATCH *in,
                                 const OSSL_DISPATCH **out,
                                 void **provctx)
  {
      OSSL_core_get_library_context_fn *c_get_libctx = NULL;
  
      for (; in->function_id != 0; in++) {
          switch (in->function_id) {
          case OSSL_FUNC_CORE_GETTABLE_PARAMS:
              c_gettable_params = OSSL_get_core_gettable_params(in);
              break;
          case OSSL_FUNC_CORE_GET_PARAMS:
              c_get_params = OSSL_get_core_get_params(in);
              break;
          case OSSL_FUNC_CORE_GET_LIBRARY_CONTEXT:
              c_get_libctx = OSSL_get_core_get_library_context(in);
              break;
          default:
              /* Just ignore anything we don't understand */
              break;
          }
      }
  
      if (c_get_libctx == NULL)
          return 0;
  
      *out = deflt_dispatch_table;
  
      /*
       * We want to make sure that all calls from this provider that requires
       * a library context use the same context as the one used to call our
       * functions.  We do that by passing it along as the provider context.
       */
      *provctx = c_get_libctx(provider);
      return 1;
  }
  