text: /*
   * Copyright 1995-2021 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
   */
  
  /* We need to use some engine deprecated APIs */
  #define OPENSSL_SUPPRESS_DEPRECATED
  
  #include <stdio.h>
  #include <openssl/objects.h>
  #include <openssl/evp.h>
  #include <openssl/ec.h>
  #ifndef FIPS_MODULE
  # include <openssl/engine.h>
  #endif
  #include <openssl/params.h>
  #include <openssl/core_names.h>
  #include "internal/cryptlib.h"
  #include "internal/provider.h"
  #include "internal/core.h"
  #include "crypto/evp.h"
  #include "evp_local.h"
  
  static void cleanup_old_md_data(EVP_MD_CTX *ctx, int force)
  {
      if (ctx->digest != NULL) {
          if (ctx->digest->cleanup != NULL
                  && !EVP_MD_CTX_test_flags(ctx, EVP_MD_CTX_FLAG_CLEANED))
              ctx->digest->cleanup(ctx);
          if (ctx->md_data != NULL && ctx->digest->ctx_size > 0
                  && (!EVP_MD_CTX_test_flags(ctx, EVP_MD_CTX_FLAG_REUSE)
                      || force)) {
              OPENSSL_clear_free(ctx->md_data, ctx->digest->ctx_size);
              ctx->md_data = NULL;
          }
      }
  }
  
  void evp_md_ctx_clear_digest(EVP_MD_CTX *ctx, int force, int keep_fetched)
  {
      if (ctx->algctx != NULL) {
          if (ctx->digest != NULL && ctx->digest->freectx != NULL)
              ctx->digest->freectx(ctx->algctx);
          ctx->algctx = NULL;
          EVP_MD_CTX_set_flags(ctx, EVP_MD_CTX_FLAG_CLEANED);
      }
  
      /* Code below to be removed when legacy support is dropped. */
  
      /*
       * Don't assume ctx->md_data was cleaned in EVP_Digest_Final, because
       * sometimes only copies of the context are ever finalised.
       */
      cleanup_old_md_data(ctx, force);
      if (force)
          ctx->digest = NULL;
  
  #if !defined(FIPS_MODULE) && !defined(OPENSSL_NO_ENGINE)
      ENGINE_finish(ctx->engine);
      ctx->engine = NULL;
  #endif
  
      /* Non legacy code, this has to be later than the ctx->digest cleaning */
      if (!keep_fetched) {
          EVP_MD_free(ctx->fetched_digest);
          ctx->fetched_digest = NULL;
          ctx->reqdigest = NULL;
      }
  }
  
  static int evp_md_ctx_reset_ex(EVP_MD_CTX *ctx, int keep_fetched)
  {
      if (ctx == NULL)
          return 1;
  
  #ifndef FIPS_MODULE
      /*
       * pctx should be freed by the user of EVP_MD_CTX
       * if EVP_MD_CTX_FLAG_KEEP_PKEY_CTX is set
       */
      if (!EVP_MD_CTX_test_flags(ctx, EVP_MD_CTX_FLAG_KEEP_PKEY_CTX)) {
          EVP_PKEY_CTX_free(ctx->pctx);
          ctx->pctx = NULL;
      }
  #endif
  
      evp_md_ctx_clear_digest(ctx, 0, keep_fetched);
      if (!keep_fetched)
          OPENSSL_cleanse(ctx, sizeof(*ctx));
  
      return 1;
  }
  
  /* This call frees resources associated with the context */
  int EVP_MD_CTX_reset(EVP_MD_CTX *ctx)
  {
      return evp_md_ctx_reset_ex(ctx, 0);
  }
  
  #ifndef FIPS_MODULE
  EVP_MD_CTX *evp_md_ctx_new_ex(EVP_PKEY *pkey, const ASN1_OCTET_STRING *id,
                                OSSL_LIB_CTX *libctx, const char *propq)
  {
      EVP_MD_CTX *ctx;
      EVP_PKEY_CTX *pctx = NULL;
  
      if ((ctx = EVP_MD_CTX_new()) == NULL
          || (pctx = EVP_PKEY_CTX_new_from_pkey(libctx, pkey, propq)) == NULL) {
          ERR_raise(ERR_LIB_ASN1, ERR_R_MALLOC_FAILURE);
          goto err;
      }
  
      if (id != NULL && EVP_PKEY_CTX_set1_id(pctx, id->data, id->length) <= 0)
          goto err;
  
      EVP_MD_CTX_set_pkey_ctx(ctx, pctx);
      return ctx;
  
   err:
      EVP_PKEY_CTX_free(pctx);
      EVP_MD_CTX_free(ctx);
      return NULL;
  }
  #endif
  
  EVP_MD_CTX *EVP_MD_CTX_new(void)
  {
      return OPENSSL_zalloc(sizeof(EVP_MD_CTX));
  }
  
  void EVP_MD_CTX_free(EVP_MD_CTX *ctx)
  {
      if (ctx == NULL)
          return;
  
      EVP_MD_CTX_reset(ctx);
      OPENSSL_free(ctx);
  }
  
  static int evp_md_init_internal(EVP_MD_CTX *ctx, const EVP_MD *type,
                                  const OSSL_PARAM params[], ENGINE *impl)
  {
  #if !defined(OPENSSL_NO_ENGINE) && !defined(FIPS_MODULE)
      ENGINE *tmpimpl = NULL;
  #endif
  
  #if !defined(FIPS_MODULE)
      if (ctx->pctx != NULL
              && EVP_PKEY_CTX_IS_SIGNATURE_OP(ctx->pctx)
              && ctx->pctx->op.sig.algctx != NULL) {
          /*
           * Prior to OpenSSL 3.0 calling EVP_DigestInit_ex() on an mdctx
           * previously initialised with EVP_DigestSignInit() would retain
           * information about the key, and re-initialise for another sign
           * operation. So in that case we redirect to EVP_DigestSignInit()
           */
          if (ctx->pctx->operation == EVP_PKEY_OP_SIGNCTX)
              return EVP_DigestSignInit(ctx, NULL, type, impl, NULL);
          if (ctx->pctx->operation == EVP_PKEY_OP_VERIFYCTX)
              return EVP_DigestVerifyInit(ctx, NULL, type, impl, NULL);
          ERR_raise(ERR_LIB_EVP, EVP_R_UPDATE_ERROR);
          return 0;
      }
  #endif
  
      EVP_MD_CTX_clear_flags(ctx, EVP_MD_CTX_FLAG_CLEANED);
  
      if (ctx->algctx != NULL) {
          if (!ossl_assert(ctx->digest != NULL)) {
              ERR_raise(ERR_LIB_EVP, EVP_R_INITIALIZATION_ERROR);
              return 0;
          }
          if (ctx->digest->freectx != NULL)
              ctx->digest->freectx(ctx->algctx);
          ctx->algctx = NULL;
      }
  
      if (type != NULL) {
          ctx->reqdigest = type;
      } else {
          if (ctx->digest == NULL) {
              ERR_raise(ERR_LIB_EVP, EVP_R_NO_DIGEST_SET);
              return 0;
          }
          type = ctx->digest;
      }
  
      /* Code below to be removed when legacy support is dropped. */
  #if !defined(OPENSSL_NO_ENGINE) && !defined(FIPS_MODULE)
      /*
       * Whether it's nice or not, "Inits" can be used on "Final"'d contexts so
       * this context may already have an ENGINE! Try to avoid releasing the
       * previous handle, re-querying for an ENGINE, and having a
       * reinitialisation, when it may all be unnecessary.
       */
      if (ctx->engine != NULL
              && ctx->digest != NULL
              && type->type == ctx->digest->type)
          goto skip_to_init;
  
      /*
       * Ensure an ENGINE left lying around from last time is cleared (the
       * previous check attempted to avoid this if the same ENGINE and
       * EVP_MD could be used).
       */
      ENGINE_finish(ctx->engine);
      ctx->engine = NULL;
  
      if (impl == NULL)
          tmpimpl = ENGINE_get_digest_engine(type->type);
  #endif
  
      /*
       * If there are engines involved or EVP_MD_CTX_FLAG_NO_INIT is set then we
       * should use legacy handling for now.
       */
      if (impl != NULL
  #if !defined(OPENSSL_NO_ENGINE)
              || ctx->engine != NULL
  # if !defined(FIPS_MODULE)
              || tmpimpl != NULL
  # endif
  #endif
              || (ctx->flags & EVP_MD_CTX_FLAG_NO_INIT) != 0
              || type->origin == EVP_ORIG_METH) {
          if (ctx->digest == ctx->fetched_digest)
              ctx->digest = NULL;
          EVP_MD_free(ctx->fetched_digest);
          ctx->fetched_digest = NULL;
          goto legacy;
      }
  
      cleanup_old_md_data(ctx, 1);
  
      /* Start of non-legacy code below */
  
      if (type->prov == NULL) {
  #ifdef FIPS_MODULE
          /* We only do explicit fetches inside the FIPS module */
          ERR_raise(ERR_LIB_EVP, EVP_R_INITIALIZATION_ERROR);
          return 0;
  #else
          /* The NULL digest is a special case */
          EVP_MD *provmd = EVP_MD_fetch(NULL,
                                        type->type != NID_undef ? OBJ_nid2sn(type->type)
                                                                : "NULL", "");
  
          if (provmd == NULL) {
              ERR_raise(ERR_LIB_EVP, EVP_R_INITIALIZATION_ERROR);
              return 0;
          }
          type = provmd;
          EVP_MD_free(ctx->fetched_digest);
          ctx->fetched_digest = provmd;
  #endif
      }
  
      if (ctx->algctx != NULL && ctx->digest != NULL && ctx->digest != type) {
          if (ctx->digest->freectx != NULL)
              ctx->digest->freectx(ctx->algctx);
          ctx->algctx = NULL;
      }
      if (type->prov != NULL && ctx->fetched_digest != type) {
          if (!EVP_MD_up_ref((EVP_MD *)type)) {
              ERR_raise(ERR_LIB_EVP, EVP_R_INITIALIZATION_ERROR);
              return 0;
          }
          EVP_MD_free(ctx->fetched_digest);
          ctx->fetched_digest = (EVP_MD *)type;
      }
      ctx->digest = type;
      if (ctx->algctx == NULL) {
          ctx->algctx = ctx->digest->newctx(ossl_provider_ctx(type->prov));
          if (ctx->algctx == NULL) {
              ERR_raise(ERR_LIB_EVP, EVP_R_INITIALIZATION_ERROR);
              return 0;
          }
      }
  
      if (ctx->digest->dinit == NULL) {
          ERR_raise(ERR_LIB_EVP, EVP_R_INITIALIZATION_ERROR);
          return 0;
      }
  
      return ctx->digest->dinit(ctx->algctx, params);
  
      /* Code below to be removed when legacy support is dropped. */
   legacy:
  
  #if !defined(OPENSSL_NO_ENGINE) && !defined(FIPS_MODULE)
      if (type) {
          if (impl != NULL) {
              if (!ENGINE_init(impl)) {
                  ERR_raise(ERR_LIB_EVP, EVP_R_INITIALIZATION_ERROR);
                  return 0;
              }
          } else {
              /* Ask if an ENGINE is reserved for this job */
              impl = tmpimpl;
          }
          if (impl != NULL) {
              /* There's an ENGINE for this job ... (apparently) */
              const EVP_MD *d = ENGINE_get_digest(impl, type->type);
  
              if (d == NULL) {
                  ERR_raise(ERR_LIB_EVP, EVP_R_INITIALIZATION_ERROR);
                  ENGINE_finish(impl);
                  return 0;
              }
              /* We'll use the ENGINE's private digest definition */
              type = d;
              /*
               * Store the ENGINE functional reference so we know 'type' came
               * from an ENGINE and we need to release it when done.
               */
              ctx->engine = impl;
          } else
              ctx->engine = NULL;
      }
  #endif
      if (ctx->digest != type) {
          cleanup_old_md_data(ctx, 1);
  
          ctx->digest = type;
          if (!(ctx->flags & EVP_MD_CTX_FLAG_NO_INIT) && type->ctx_size) {
              ctx->update = type->update;
              ctx->md_data = OPENSSL_zalloc(type->ctx_size);
              if (ctx->md_data == NULL) {
                  ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
                  return 0;
              }
          }
      }
  #if !defined(OPENSSL_NO_ENGINE) && !defined(FIPS_MODULE)
   skip_to_init:
  #endif
  #ifndef FIPS_MODULE
      if (ctx->pctx != NULL
              && (!EVP_PKEY_CTX_IS_SIGNATURE_OP(ctx->pctx)
                   || ctx->pctx->op.sig.signature == NULL)) {
          int r;
          r = EVP_PKEY_CTX_ctrl(ctx->pctx, -1, EVP_PKEY_OP_TYPE_SIG,
                                EVP_PKEY_CTRL_DIGESTINIT, 0, ctx);
          if (r <= 0 && (r != -2))
              return 0;
      }
  #endif
      if (ctx->flags & EVP_MD_CTX_FLAG_NO_INIT)
          return 1;
      return ctx->digest->init(ctx);
  }
  
  int EVP_DigestInit_ex2(EVP_MD_CTX *ctx, const EVP_MD *type,
                         const OSSL_PARAM params[])
  {
      return evp_md_init_internal(ctx, type, params, NULL);
  }
  
  int EVP_DigestInit(EVP_MD_CTX *ctx, const EVP_MD *type)
  {
      EVP_MD_CTX_reset(ctx);
      return evp_md_init_internal(ctx, type, NULL, NULL);
  }
  
  int EVP_DigestInit_ex(EVP_MD_CTX *ctx, const EVP_MD *type, ENGINE *impl)
  {
      return evp_md_init_internal(ctx, type, NULL, impl);
  }
  
  int EVP_DigestUpdate(EVP_MD_CTX *ctx, const void *data, size_t count)
  {
      if (count == 0)
          return 1;
  
      if (ctx->pctx != NULL
              && EVP_PKEY_CTX_IS_SIGNATURE_OP(ctx->pctx)
              && ctx->pctx->op.sig.algctx != NULL) {
          /*
           * Prior to OpenSSL 3.0 EVP_DigestSignUpdate() and
           * EVP_DigestVerifyUpdate() were just macros for EVP_DigestUpdate().
           * Some code calls EVP_DigestUpdate() directly even when initialised
           * with EVP_DigestSignInit_ex() or
           * EVP_DigestVerifyInit_ex(), so we detect that and redirect to
           * the correct EVP_Digest*Update() function
           */
          if (ctx->pctx->operation == EVP_PKEY_OP_SIGNCTX)
              return EVP_DigestSignUpdate(ctx, data, count);
          if (ctx->pctx->operation == EVP_PKEY_OP_VERIFYCTX)
              return EVP_DigestVerifyUpdate(ctx, data, count);
          ERR_raise(ERR_LIB_EVP, EVP_R_UPDATE_ERROR);
          return 0;
      }
  
      if (ctx->digest == NULL
              || ctx->digest->prov == NULL
              || (ctx->flags & EVP_MD_CTX_FLAG_NO_INIT) != 0)
          goto legacy;
  
      if (ctx->digest->dupdate == NULL) {
          ERR_raise(ERR_LIB_EVP, EVP_R_UPDATE_ERROR);
          return 0;
      }
      return ctx->digest->dupdate(ctx->algctx, data, count);
  
      /* Code below to be removed when legacy support is dropped. */
   legacy:
      return ctx->update(ctx, data, count);
  }
  
  /* The caller can assume that this removes any secret data from the context */
  int EVP_DigestFinal(EVP_MD_CTX *ctx, unsigned char *md, unsigned int *size)
  {
      int ret;
      ret = EVP_DigestFinal_ex(ctx, md, size);
      EVP_MD_CTX_reset(ctx);
      return ret;
  }
  
  /* The caller can assume that this removes any secret data from the context */
  int EVP_DigestFinal_ex(EVP_MD_CTX *ctx, unsigned char *md, unsigned int *isize)
  {
      int ret, sz;
      size_t size = 0;
      size_t mdsize = 0;
  
      if (ctx->digest == NULL)
          return 0;
  
      sz = EVP_MD_get_size(ctx->digest);
      if (sz < 0)
          return 0;
      mdsize = sz;
      if (ctx->digest->prov == NULL)
          goto legacy;
  
      if (ctx->digest->dfinal == NULL) {
          ERR_raise(ERR_LIB_EVP, EVP_R_FINAL_ERROR);
          return 0;
      }
  
      ret = ctx->digest->dfinal(ctx->algctx, md, &size, mdsize);
  
      if (isize != NULL) {
          if (size <= UINT_MAX) {
              *isize = (int)size;
          } else {
              ERR_raise(ERR_LIB_EVP, EVP_R_FINAL_ERROR);
              ret = 0;
          }
      }
  
      return ret;
  
      /* Code below to be removed when legacy support is dropped. */
   legacy:
      OPENSSL_assert(mdsize <= EVP_MAX_MD_SIZE);
      ret = ctx->digest->final(ctx, md);
      if (isize != NULL)
          *isize = mdsize;
      if (ctx->digest->cleanup) {
          ctx->digest->cleanup(ctx);
          EVP_MD_CTX_set_flags(ctx, EVP_MD_CTX_FLAG_CLEANED);
      }
      OPENSSL_cleanse(ctx->md_data, ctx->digest->ctx_size);
      return ret;
  }
  
  int EVP_DigestFinalXOF(EVP_MD_CTX *ctx, unsigned char *md, size_t size)
  {
      int ret = 0;
      OSSL_PARAM params[2];
      size_t i = 0;
  
      if (ctx->digest == NULL) {
          ERR_raise(ERR_LIB_EVP, EVP_R_INVALID_NULL_ALGORITHM);
          return 0;
      }
  
      if (ctx->digest->prov == NULL)
          goto legacy;
  
      if (ctx->digest->dfinal == NULL) {
          ERR_raise(ERR_LIB_EVP, EVP_R_FINAL_ERROR);
          return 0;
      }
  
      params[i++] = OSSL_PARAM_construct_size_t(OSSL_DIGEST_PARAM_XOFLEN, &size);
      params[i++] = OSSL_PARAM_construct_end();
  
      if (EVP_MD_CTX_set_params(ctx, params) > 0)
          ret = ctx->digest->dfinal(ctx->algctx, md, &size, size);
  
      return ret;
  
  legacy:
      if (ctx->digest->flags & EVP_MD_FLAG_XOF
          && size <= INT_MAX
          && ctx->digest->md_ctrl(ctx, EVP_MD_CTRL_XOF_LEN, (int)size, NULL)) {
          ret = ctx->digest->final(ctx, md);
          if (ctx->digest->cleanup != NULL) {
              ctx->digest->cleanup(ctx);
              EVP_MD_CTX_set_flags(ctx, EVP_MD_CTX_FLAG_CLEANED);
          }
          OPENSSL_cleanse(ctx->md_data, ctx->digest->ctx_size);
      } else {
          ERR_raise(ERR_LIB_EVP, EVP_R_NOT_XOF_OR_INVALID_LENGTH);
      }
  
      return ret;
  }
  
  EVP_MD_CTX *EVP_MD_CTX_dup(const EVP_MD_CTX *in)
  {
      EVP_MD_CTX *out = EVP_MD_CTX_new();
  
      if (out != NULL && !EVP_MD_CTX_copy_ex(out, in)) {
          EVP_MD_CTX_free(out);
          out = NULL;
      }
      return out;
  }
  
  int EVP_MD_CTX_copy(EVP_MD_CTX *out, const EVP_MD_CTX *in)
  {
      EVP_MD_CTX_reset(out);
      return EVP_MD_CTX_copy_ex(out, in);
  }
  
  int EVP_MD_CTX_copy_ex(EVP_MD_CTX *out, const EVP_MD_CTX *in)
  {
      int digest_change = 0;
      unsigned char *tmp_buf;
  
      if (in == NULL) {
          ERR_raise(ERR_LIB_EVP, ERR_R_PASSED_NULL_PARAMETER);
          return 0;
      }
  
      if (in->digest == NULL) {
          /* copying uninitialized digest context */
          EVP_MD_CTX_reset(out);
          if (out->fetched_digest != NULL)
              EVP_MD_free(out->fetched_digest);
          *out = *in;
          goto clone_pkey;
      }
  
      if (in->digest->prov == NULL
              || (in->flags & EVP_MD_CTX_FLAG_NO_INIT) != 0)
          goto legacy;
  
      if (in->digest->dupctx == NULL) {
          ERR_raise(ERR_LIB_EVP, EVP_R_NOT_ABLE_TO_COPY_CTX);
          return 0;
      }
  
      evp_md_ctx_reset_ex(out, 1);
      digest_change = (out->fetched_digest != in->fetched_digest);
      if (digest_change && out->fetched_digest != NULL)
          EVP_MD_free(out->fetched_digest);
      *out = *in;
      /* NULL out pointers in case of error */
      out->pctx = NULL;
      out->algctx = NULL;
  
      if (digest_change && in->fetched_digest != NULL)
          EVP_MD_up_ref(in->fetched_digest);
  
      if (in->algctx != NULL) {
          out->algctx = in->digest->dupctx(in->algctx);
          if (out->algctx == NULL) {
              ERR_raise(ERR_LIB_EVP, EVP_R_NOT_ABLE_TO_COPY_CTX);
              return 0;
          }
      }
  
   clone_pkey:
      /* copied EVP_MD_CTX should free the copied EVP_PKEY_CTX */
      EVP_MD_CTX_clear_flags(out, EVP_MD_CTX_FLAG_KEEP_PKEY_CTX);
  #ifndef FIPS_MODULE
      if (in->pctx != NULL) {
          out->pctx = EVP_PKEY_CTX_dup(in->pctx);
          if (out->pctx == NULL) {
              ERR_raise(ERR_LIB_EVP, EVP_R_NOT_ABLE_TO_COPY_CTX);
              EVP_MD_CTX_reset(out);
              return 0;
          }
      }
  #endif
  
      return 1;
  
      /* Code below to be removed when legacy support is dropped. */
   legacy:
  #if !defined(OPENSSL_NO_ENGINE) && !defined(FIPS_MODULE)
      /* Make sure it's safe to copy a digest context using an ENGINE */
      if (in->engine && !ENGINE_init(in->engine)) {
          ERR_raise(ERR_LIB_EVP, ERR_R_ENGINE_LIB);
          return 0;
      }
  #endif
  
      if (out->digest == in->digest) {
          tmp_buf = out->md_data;
          EVP_MD_CTX_set_flags(out, EVP_MD_CTX_FLAG_REUSE);
      } else
          tmp_buf = NULL;
      EVP_MD_CTX_reset(out);
      memcpy(out, in, sizeof(*out));
  
      /* copied EVP_MD_CTX should free the copied EVP_PKEY_CTX */
      EVP_MD_CTX_clear_flags(out, EVP_MD_CTX_FLAG_KEEP_PKEY_CTX);
  
      /* Null these variables, since they are getting fixed up
       * properly below.  Anything else may cause a memleak and/or
       * double free if any of the memory allocations below fail
       */
      out->md_data = NULL;
      out->pctx = NULL;
  
      if (in->md_data && out->digest->ctx_size) {
          if (tmp_buf)
              out->md_data = tmp_buf;
          else {
              out->md_data = OPENSSL_malloc(out->digest->ctx_size);
              if (out->md_data == NULL) {
                  ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
                  return 0;
              }
          }
          memcpy(out->md_data, in->md_data, out->digest->ctx_size);
      }
  
      out->update = in->update;
  
  #ifndef FIPS_MODULE
      if (in->pctx) {
          out->pctx = EVP_PKEY_CTX_dup(in->pctx);
          if (!out->pctx) {
              EVP_MD_CTX_reset(out);
              return 0;
          }
      }
  #endif
  
      if (out->digest->copy)
          return out->digest->copy(out, in);
  
      return 1;
  }
  
  int EVP_Digest(const void *data, size_t count,
                 unsigned char *md, unsigned int *size, const EVP_MD *type,
                 ENGINE *impl)
  {
      EVP_MD_CTX *ctx = EVP_MD_CTX_new();
      int ret;
  
      if (ctx == NULL)
          return 0;
      EVP_MD_CTX_set_flags(ctx, EVP_MD_CTX_FLAG_ONESHOT);
      ret = EVP_DigestInit_ex(ctx, type, impl)
          && EVP_DigestUpdate(ctx, data, count)
          && EVP_DigestFinal_ex(ctx, md, size);
      EVP_MD_CTX_free(ctx);
  
      return ret;
  }
  
  int EVP_Q_digest(OSSL_LIB_CTX *libctx, const char *name, const char *propq,
                   const void *data, size_t datalen,
                   unsigned char *md, size_t *mdlen)
  {
      EVP_MD *digest = EVP_MD_fetch(libctx, name, propq);
      unsigned int temp = 0;
      int ret = 0;
  
      if (digest != NULL) {
          ret = EVP_Digest(data, datalen, md, &temp, digest, NULL);
          EVP_MD_free(digest);
      }
      if (mdlen != NULL)
          *mdlen = temp;
      return ret;
  }
  
  int EVP_MD_get_params(const EVP_MD *digest, OSSL_PARAM params[])
  {
      if (digest != NULL && digest->get_params != NULL)
          return digest->get_params(params);
      return 0;
  }
  
  const OSSL_PARAM *EVP_MD_gettable_params(const EVP_MD *digest)
  {
      if (digest != NULL && digest->gettable_params != NULL)
          return digest->gettable_params(
                             ossl_provider_ctx(EVP_MD_get0_provider(digest)));
      return NULL;
  }
  
  int EVP_MD_CTX_set_params(EVP_MD_CTX *ctx, const OSSL_PARAM params[])
  {
      EVP_PKEY_CTX *pctx = ctx->pctx;
  
      /* If we have a pctx then we should try that first */
      if (pctx != NULL
              && (pctx->operation == EVP_PKEY_OP_VERIFYCTX
                  || pctx->operation == EVP_PKEY_OP_SIGNCTX)
              && pctx->op.sig.algctx != NULL
              && pctx->op.sig.signature->set_ctx_md_params != NULL)
          return pctx->op.sig.signature->set_ctx_md_params(pctx->op.sig.algctx,
                                                           params);
  
      if (ctx->digest != NULL && ctx->digest->set_ctx_params != NULL)
          return ctx->digest->set_ctx_params(ctx->algctx, params);
  
      return 0;
  }
  
  const OSSL_PARAM *EVP_MD_settable_ctx_params(const EVP_MD *md)
  {
      void *provctx;
  
      if (md != NULL && md->settable_ctx_params != NULL) {
          provctx = ossl_provider_ctx(EVP_MD_get0_provider(md));
          return md->settable_ctx_params(NULL, provctx);
      }
      return NULL;
  }
  
  const OSSL_PARAM *EVP_MD_CTX_settable_params(EVP_MD_CTX *ctx)
  {
      EVP_PKEY_CTX *pctx;
      void *alg;
  
      if (ctx == NULL)
          return NULL;
  
      /* If we have a pctx then we should try that first */
      pctx = ctx->pctx;
      if (pctx != NULL
              && (pctx->operation == EVP_PKEY_OP_VERIFYCTX
                  || pctx->operation == EVP_PKEY_OP_SIGNCTX)
              && pctx->op.sig.algctx != NULL
              && pctx->op.sig.signature->settable_ctx_md_params != NULL)
          return pctx->op.sig.signature->settable_ctx_md_params(
                     pctx->op.sig.algctx);
  
      if (ctx->digest != NULL && ctx->digest->settable_ctx_params != NULL) {
          alg = ossl_provider_ctx(EVP_MD_get0_provider(ctx->digest));
          return ctx->digest->settable_ctx_params(ctx->algctx, alg);
      }
  
      return NULL;
  }
  
  int EVP_MD_CTX_get_params(EVP_MD_CTX *ctx, OSSL_PARAM params[])
  {
      EVP_PKEY_CTX *pctx = ctx->pctx;
  
      /* If we have a pctx then we should try that first */
      if (pctx != NULL
              && (pctx->operation == EVP_PKEY_OP_VERIFYCTX
                  || pctx->operation == EVP_PKEY_OP_SIGNCTX)
              && pctx->op.sig.algctx != NULL
              && pctx->op.sig.signature->get_ctx_md_params != NULL)
          return pctx->op.sig.signature->get_ctx_md_params(pctx->op.sig.algctx,
                                                           params);
  
      if (ctx->digest != NULL && ctx->digest->get_params != NULL)
          return ctx->digest->get_ctx_params(ctx->algctx, params);
  
      return 0;
  }
  
  const OSSL_PARAM *EVP_MD_gettable_ctx_params(const EVP_MD *md)
  {
      void *provctx;
  
      if (md != NULL && md->gettable_ctx_params != NULL) {
          provctx = ossl_provider_ctx(EVP_MD_get0_provider(md));
          return md->gettable_ctx_params(NULL, provctx);
      }
      return NULL;
  }
  
  const OSSL_PARAM *EVP_MD_CTX_gettable_params(EVP_MD_CTX *ctx)
  {
      EVP_PKEY_CTX *pctx;
      void *provctx;
  
      if (ctx == NULL)
          return NULL;
  
      /* If we have a pctx then we should try that first */
      pctx = ctx->pctx;
      if (pctx != NULL
              && (pctx->operation == EVP_PKEY_OP_VERIFYCTX
                  || pctx->operation == EVP_PKEY_OP_SIGNCTX)
              && pctx->op.sig.algctx != NULL
              && pctx->op.sig.signature->gettable_ctx_md_params != NULL)
          return pctx->op.sig.signature->gettable_ctx_md_params(
                      pctx->op.sig.algctx);
  
      if (ctx->digest != NULL && ctx->digest->gettable_ctx_params != NULL) {
          provctx = ossl_provider_ctx(EVP_MD_get0_provider(ctx->digest));
          return ctx->digest->gettable_ctx_params(ctx->algctx, provctx);
      }
      return NULL;
  }
  
  int EVP_MD_CTX_ctrl(EVP_MD_CTX *ctx, int cmd, int p1, void *p2)
  {
      int ret = EVP_CTRL_RET_UNSUPPORTED;
      int set_params = 1;
      size_t sz;
      OSSL_PARAM params[2] = { OSSL_PARAM_END, OSSL_PARAM_END };
  
      if (ctx == NULL) {
          ERR_raise(ERR_LIB_EVP, ERR_R_PASSED_NULL_PARAMETER);
          return 0;
      }
  
      if (ctx->digest != NULL && ctx->digest->prov == NULL)
          goto legacy;
  
      switch (cmd) {
      case EVP_MD_CTRL_XOF_LEN:
          sz = (size_t)p1;
          params[0] = OSSL_PARAM_construct_size_t(OSSL_DIGEST_PARAM_XOFLEN, &sz);
          break;
      case EVP_MD_CTRL_MICALG:
          set_params = 0;
          params[0] = OSSL_PARAM_construct_utf8_string(OSSL_DIGEST_PARAM_MICALG,
                                                       p2, p1 ? p1 : 9999);
          break;
      case EVP_CTRL_SSL3_MASTER_SECRET:
          params[0] = OSSL_PARAM_construct_octet_string(OSSL_DIGEST_PARAM_SSL3_MS,
                                                        p2, p1);
          break;
      default:
          goto conclude;
      }
  
      if (set_params)
          ret = EVP_MD_CTX_set_params(ctx, params);
      else
          ret = EVP_MD_CTX_get_params(ctx, params);
      goto conclude;
  
  
      /* Code below to be removed when legacy support is dropped. */
   legacy:
      if (ctx->digest->md_ctrl == NULL) {
          ERR_raise(ERR_LIB_EVP, EVP_R_CTRL_NOT_IMPLEMENTED);
          return 0;
      }
  
      ret = ctx->digest->md_ctrl(ctx, cmd, p1, p2);
   conclude:
      if (ret <= 0)
          return 0;
      return ret;
  }
  
  EVP_MD *evp_md_new(void)
  {
      EVP_MD *md = OPENSSL_zalloc(sizeof(*md));
  
      if (md != NULL) {
          md->lock = CRYPTO_THREAD_lock_new();
          if (md->lock == NULL) {
              OPENSSL_free(md);
              return NULL;
          }
          md->refcnt = 1;
      }
      return md;
  }
  
  /*
   * FIPS module note: since internal fetches will be entirely
   * provider based, we know that none of its code depends on legacy
   * NIDs or any functionality that use them.
   */
  #ifndef FIPS_MODULE
  static void set_legacy_nid(const char *name, void *vlegacy_nid)
  {
      int nid;
      int *legacy_nid = vlegacy_nid;
      /*
       * We use lowest level function to get the associated method, because
       * higher level functions such as EVP_get_digestbyname() have changed
       * to look at providers too.
       */
      const void *legacy_method = OBJ_NAME_get(name, OBJ_NAME_TYPE_MD_METH);
  
      if (*legacy_nid == -1)       /* We found a clash already */
          return;
  
      if (legacy_method == NULL)
          return;
      nid = EVP_MD_nid(legacy_method);
      if (*legacy_nid != NID_undef && *legacy_nid != nid) {
          *legacy_nid = -1;
          return;
      }
      *legacy_nid = nid;
  }
  #endif
  
  static int evp_md_cache_constants(EVP_MD *md)
  {
      int ok, xof = 0, algid_absent = 0;
      size_t blksz = 0;
      size_t mdsize = 0;
      OSSL_PARAM params[5];
  
      params[0] = OSSL_PARAM_construct_size_t(OSSL_DIGEST_PARAM_BLOCK_SIZE, &blksz);
      params[1] = OSSL_PARAM_construct_size_t(OSSL_DIGEST_PARAM_SIZE, &mdsize);
      params[2] = OSSL_PARAM_construct_int(OSSL_DIGEST_PARAM_XOF, &xof);
      params[3] = OSSL_PARAM_construct_int(OSSL_DIGEST_PARAM_ALGID_ABSENT,
                                           &algid_absent);
      params[4] = OSSL_PARAM_construct_end();
      ok = evp_do_md_getparams(md, params) > 0;
      if (mdsize > INT_MAX || blksz > INT_MAX)
          ok = 0;
      if (ok) {
          md->block_size = (int)blksz;
          md->md_size = (int)mdsize;
          if (xof)
              md->flags |= EVP_MD_FLAG_XOF;
          if (algid_absent)
              md->flags |= EVP_MD_FLAG_DIGALGID_ABSENT;
      }
      return ok;
  }
  
  static void *evp_md_from_algorithm(int name_id,
                                     const OSSL_ALGORITHM *algodef,
                                     OSSL_PROVIDER *prov)
  {
      const OSSL_DISPATCH *fns = algodef->implementation;
      EVP_MD *md = NULL;
      int fncnt = 0;
  
      /* EVP_MD_fetch() will set the legacy NID if available */
      if ((md = evp_md_new()) == NULL) {
          ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
          return NULL;
      }
  
  #ifndef FIPS_MODULE
      md->type = NID_undef;
      if (!evp_names_do_all(prov, name_id, set_legacy_nid, &md->type)
              || md->type == -1) {
          ERR_raise(ERR_LIB_EVP, ERR_R_INTERNAL_ERROR);
          EVP_MD_free(md);
          return NULL;
      }
  #endif
  
      md->name_id = name_id;
      if ((md->type_name = ossl_algorithm_get1_first_name(algodef)) == NULL) {
          EVP_MD_free(md);
          return NULL;
      }
      md->description = algodef->algorithm_description;
  
      for (; fns->function_id != 0; fns++) {
          switch (fns->function_id) {
          case OSSL_FUNC_DIGEST_NEWCTX:
              if (md->newctx == NULL) {
                  md->newctx = OSSL_FUNC_digest_newctx(fns);
                  fncnt++;
              }
              break;
          case OSSL_FUNC_DIGEST_INIT:
              if (md->dinit == NULL) {
                  md->dinit = OSSL_FUNC_digest_init(fns);
                  fncnt++;
              }
              break;
          case OSSL_FUNC_DIGEST_UPDATE:
              if (md->dupdate == NULL) {
                  md->dupdate = OSSL_FUNC_digest_update(fns);
                  fncnt++;
              }
              break;
          case OSSL_FUNC_DIGEST_FINAL:
              if (md->dfinal == NULL) {
                  md->dfinal = OSSL_FUNC_digest_final(fns);
                  fncnt++;
              }
              break;
          case OSSL_FUNC_DIGEST_DIGEST:
              if (md->digest == NULL)
                  md->digest = OSSL_FUNC_digest_digest(fns);
              /* We don't increment fnct for this as it is stand alone */
              break;
          case OSSL_FUNC_DIGEST_FREECTX:
              if (md->freectx == NULL) {
                  md->freectx = OSSL_FUNC_digest_freectx(fns);
                  fncnt++;
              }
              break;
          case OSSL_FUNC_DIGEST_DUPCTX:
              if (md->dupctx == NULL)
                  md->dupctx = OSSL_FUNC_digest_dupctx(fns);
              break;
          case OSSL_FUNC_DIGEST_GET_PARAMS:
              if (md->get_params == NULL)
                  md->get_params = OSSL_FUNC_digest_get_params(fns);
              break;
          case OSSL_FUNC_DIGEST_SET_CTX_PARAMS:
              if (md->set_ctx_params == NULL)
                  md->set_ctx_params = OSSL_FUNC_digest_set_ctx_params(fns);
              break;
          case OSSL_FUNC_DIGEST_GET_CTX_PARAMS:
              if (md->get_ctx_params == NULL)
                  md->get_ctx_params = OSSL_FUNC_digest_get_ctx_params(fns);
              break;
          case OSSL_FUNC_DIGEST_GETTABLE_PARAMS:
              if (md->gettable_params == NULL)
                  md->gettable_params = OSSL_FUNC_digest_gettable_params(fns);
              break;
          case OSSL_FUNC_DIGEST_SETTABLE_CTX_PARAMS:
              if (md->settable_ctx_params == NULL)
                  md->settable_ctx_params =
                      OSSL_FUNC_digest_settable_ctx_params(fns);
              break;
          case OSSL_FUNC_DIGEST_GETTABLE_CTX_PARAMS:
              if (md->gettable_ctx_params == NULL)
                  md->gettable_ctx_params =
                      OSSL_FUNC_digest_gettable_ctx_params(fns);
              break;
          }
      }
      if ((fncnt != 0 && fncnt != 5)
          || (fncnt == 0 && md->digest == NULL)) {
          /*
           * In order to be a consistent set of functions we either need the
           * whole set of init/update/final etc functions or none of them.
           * The "digest" function can standalone. We at least need one way to
           * generate digests.
           */
          EVP_MD_free(md);
          ERR_raise(ERR_LIB_EVP, EVP_R_INVALID_PROVIDER_FUNCTIONS);
          return NULL;
      }
      md->prov = prov;
      if (prov != NULL)
          ossl_provider_up_ref(prov);
  
      if (!evp_md_cache_constants(md)) {
          EVP_MD_free(md);
          ERR_raise(ERR_LIB_EVP, EVP_R_CACHE_CONSTANTS_FAILED);
          md = NULL;
      }
  
      return md;
  }
  
  static int evp_md_up_ref(void *md)
  {
      return EVP_MD_up_ref(md);
  }
  
  static void evp_md_free(void *md)
  {
      EVP_MD_free(md);
  }
  
  EVP_MD *EVP_MD_fetch(OSSL_LIB_CTX *ctx, const char *algorithm,
                       const char *properties)
  {
      EVP_MD *md =
          evp_generic_fetch(ctx, OSSL_OP_DIGEST, algorithm, properties,
                            evp_md_from_algorithm, evp_md_up_ref, evp_md_free);
  
      return md;
  }
  
  int EVP_MD_up_ref(EVP_MD *md)
  {
      int ref = 0;
  
      if (md->origin == EVP_ORIG_DYNAMIC)
          CRYPTO_UP_REF(&md->refcnt, &ref, md->lock);
      return 1;
  }
  
  void EVP_MD_free(EVP_MD *md)
  {
      int i;
  
      if (md == NULL || md->origin != EVP_ORIG_DYNAMIC)
          return;
  
      CRYPTO_DOWN_REF(&md->refcnt, &i, md->lock);
      if (i > 0)
          return;
      evp_md_free_int(md);
  }
  
  void EVP_MD_do_all_provided(OSSL_LIB_CTX *libctx,
                              void (*fn)(EVP_MD *mac, void *arg),
                              void *arg)
  {
      evp_generic_do_all(libctx, OSSL_OP_DIGEST,
                         (void (*)(void *, void *))fn, arg,
                         evp_md_from_algorithm, evp_md_up_ref, evp_md_free);
  }
  