text: /*
   * Copyright 2006-2020 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 <stdio.h>
  #include <stdlib.h>
  #include <openssl/objects.h>
  #include <openssl/evp.h>
  #include "internal/cryptlib.h"
  #include "crypto/evp.h"
  #include "internal/provider.h"
  #include "evp_local.h"
  
  static int evp_pkey_asym_cipher_init(EVP_PKEY_CTX *ctx, int operation)
  {
      int ret = 0;
      void *provkey = NULL;
      EVP_ASYM_CIPHER *cipher = NULL;
      EVP_KEYMGMT *tmp_keymgmt = NULL;
      const char *supported_ciph = NULL;
  
      if (ctx == NULL) {
          EVPerr(0, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
          return -2;
      }
  
      evp_pkey_ctx_free_old_ops(ctx);
      ctx->operation = operation;
  
      /*
       * TODO when we stop falling back to legacy, this and the ERR_pop_to_mark()
       * calls can be removed.
       */
      ERR_set_mark();
  
      if (ctx->engine != NULL || ctx->keytype == NULL)
          goto legacy;
  
      /*
       * Ensure that the key is provided, either natively, or as a cached export.
       *  If not, go legacy
       */
      tmp_keymgmt = ctx->keymgmt;
      provkey = evp_pkey_export_to_provider(ctx->pkey, ctx->libctx,
                                            &tmp_keymgmt, ctx->propquery);
      if (provkey == NULL)
          goto legacy;
      if (!EVP_KEYMGMT_up_ref(tmp_keymgmt)) {
          ERR_clear_last_mark();
          ERR_raise(ERR_LIB_EVP, EVP_R_INITIALIZATION_ERROR);
          goto err;
      }
      EVP_KEYMGMT_free(ctx->keymgmt);
      ctx->keymgmt = tmp_keymgmt;
  
      if (ctx->keymgmt->query_operation_name != NULL)
          supported_ciph =
              ctx->keymgmt->query_operation_name(OSSL_OP_ASYM_CIPHER);
  
      /*
       * If we didn't get a supported ciph, assume there is one with the
       * same name as the key type.
       */
      if (supported_ciph == NULL)
          supported_ciph = ctx->keytype;
  
      /*
       * Because we cleared out old ops, we shouldn't need to worry about
       * checking if cipher is already there.
       */
      cipher =
          EVP_ASYM_CIPHER_fetch(ctx->libctx, supported_ciph, ctx->propquery);
  
      if (cipher == NULL
          || (EVP_KEYMGMT_provider(ctx->keymgmt)
              != EVP_ASYM_CIPHER_provider(cipher))) {
          /*
           * We don't need to free ctx->keymgmt here, as it's not necessarily
           * tied to this operation.  It will be freed by EVP_PKEY_CTX_free().
           */
          EVP_ASYM_CIPHER_free(cipher);
          goto legacy;
      }
  
      /*
       * TODO remove this when legacy is gone
       * If we don't have the full support we need with provided methods,
       * let's go see if legacy does.
       */
      ERR_pop_to_mark();
  
      /* No more legacy from here down to legacy: */
  
      ctx->op.ciph.cipher = cipher;
      ctx->op.ciph.ciphprovctx = cipher->newctx(ossl_provider_ctx(cipher->prov));
      if (ctx->op.ciph.ciphprovctx == NULL) {
          /* The provider key can stay in the cache */
          EVPerr(0, EVP_R_INITIALIZATION_ERROR);
          goto err;
      }
  
      switch (operation) {
      case EVP_PKEY_OP_ENCRYPT:
          if (cipher->encrypt_init == NULL) {
              EVPerr(0, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
              ret = -2;
              goto err;
          }
          ret = cipher->encrypt_init(ctx->op.ciph.ciphprovctx, provkey);
          break;
      case EVP_PKEY_OP_DECRYPT:
          if (cipher->decrypt_init == NULL) {
              EVPerr(0, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
              ret = -2;
              goto err;
          }
          ret = cipher->decrypt_init(ctx->op.ciph.ciphprovctx, provkey);
          break;
      default:
          EVPerr(0, EVP_R_INITIALIZATION_ERROR);
          goto err;
      }
  
      if (ret <= 0)
          goto err;
      return 1;
  
   legacy:
      /*
       * TODO remove this when legacy is gone
       * If we don't have the full support we need with provided methods,
       * let's go see if legacy does.
       */
      ERR_pop_to_mark();
  
      if (ctx->pmeth == NULL || ctx->pmeth->encrypt == NULL) {
          EVPerr(0, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
          return -2;
      }
      switch(ctx->operation) {
      case EVP_PKEY_OP_ENCRYPT:
          if (ctx->pmeth->encrypt_init == NULL)
              return 1;
          ret = ctx->pmeth->encrypt_init(ctx);
          break;
      case EVP_PKEY_OP_DECRYPT:
          if (ctx->pmeth->decrypt_init == NULL)
              return 1;
          ret = ctx->pmeth->decrypt_init(ctx);
          break;
      default:
          EVPerr(0, EVP_R_INITIALIZATION_ERROR);
          ret = -1;
      }
  
   err:
      if (ret <= 0) {
          evp_pkey_ctx_free_old_ops(ctx);
          ctx->operation = EVP_PKEY_OP_UNDEFINED;
      }
      return ret;
  }
  
  int EVP_PKEY_encrypt_init(EVP_PKEY_CTX *ctx)
  {
      return evp_pkey_asym_cipher_init(ctx, EVP_PKEY_OP_ENCRYPT);
  }
  
  int EVP_PKEY_encrypt(EVP_PKEY_CTX *ctx,
                       unsigned char *out, size_t *outlen,
                       const unsigned char *in, size_t inlen)
  {
      int ret;
  
      if (ctx == NULL) {
          EVPerr(0, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
          return -2;
      }
  
      if (ctx->operation != EVP_PKEY_OP_ENCRYPT) {
          EVPerr(0, EVP_R_OPERATON_NOT_INITIALIZED);
          return -1;
      }
  
      if (ctx->op.ciph.ciphprovctx == NULL)
          goto legacy;
  
      ret = ctx->op.ciph.cipher->encrypt(ctx->op.ciph.ciphprovctx, out, outlen,
                                         (out == NULL ? 0 : *outlen), in, inlen);
      return ret;
  
   legacy:
      if (ctx->pmeth == NULL || ctx->pmeth->encrypt == NULL) {
          EVPerr(EVP_F_EVP_PKEY_ENCRYPT,
                 EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
          return -2;
      }
      M_check_autoarg(ctx, out, outlen, EVP_F_EVP_PKEY_ENCRYPT)
          return ctx->pmeth->encrypt(ctx, out, outlen, in, inlen);
  }
  
  int EVP_PKEY_decrypt_init(EVP_PKEY_CTX *ctx)
  {
      return evp_pkey_asym_cipher_init(ctx, EVP_PKEY_OP_DECRYPT);
  }
  
  int EVP_PKEY_decrypt(EVP_PKEY_CTX *ctx,
                       unsigned char *out, size_t *outlen,
                       const unsigned char *in, size_t inlen)
  {
      int ret;
  
      if (ctx == NULL) {
          EVPerr(0, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
          return -2;
      }
  
      if (ctx->operation != EVP_PKEY_OP_DECRYPT) {
          EVPerr(0, EVP_R_OPERATON_NOT_INITIALIZED);
          return -1;
      }
  
      if (ctx->op.ciph.ciphprovctx == NULL)
          goto legacy;
  
      ret = ctx->op.ciph.cipher->decrypt(ctx->op.ciph.ciphprovctx, out, outlen,
                                         (out == NULL ? 0 : *outlen), in, inlen);
      return ret;
  
   legacy:
      if (ctx->pmeth == NULL || ctx->pmeth->decrypt == NULL) {
          EVPerr(EVP_F_EVP_PKEY_DECRYPT,
                 EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
          return -2;
      }
      M_check_autoarg(ctx, out, outlen, EVP_F_EVP_PKEY_DECRYPT)
          return ctx->pmeth->decrypt(ctx, out, outlen, in, inlen);
  }
  
  
  static EVP_ASYM_CIPHER *evp_asym_cipher_new(OSSL_PROVIDER *prov)
  {
      EVP_ASYM_CIPHER *cipher = OPENSSL_zalloc(sizeof(EVP_ASYM_CIPHER));
  
      if (cipher == NULL) {
          ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
          return NULL;
      }
  
      cipher->lock = CRYPTO_THREAD_lock_new();
      if (cipher->lock == NULL) {
          ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
          OPENSSL_free(cipher);
          return NULL;
      }
      cipher->prov = prov;
      ossl_provider_up_ref(prov);
      cipher->refcnt = 1;
  
      return cipher;
  }
  
  static void *evp_asym_cipher_from_dispatch(int name_id,
                                             const OSSL_DISPATCH *fns,
                                             OSSL_PROVIDER *prov)
  {
      EVP_ASYM_CIPHER *cipher = NULL;
      int ctxfncnt = 0, encfncnt = 0, decfncnt = 0;
      int gparamfncnt = 0, sparamfncnt = 0;
  
      if ((cipher = evp_asym_cipher_new(prov)) == NULL) {
          ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
          goto err;
      }
  
      cipher->name_id = name_id;
  
      for (; fns->function_id != 0; fns++) {
          switch (fns->function_id) {
          case OSSL_FUNC_ASYM_CIPHER_NEWCTX:
              if (cipher->newctx != NULL)
                  break;
              cipher->newctx = OSSL_FUNC_asym_cipher_newctx(fns);
              ctxfncnt++;
              break;
          case OSSL_FUNC_ASYM_CIPHER_ENCRYPT_INIT:
              if (cipher->encrypt_init != NULL)
                  break;
              cipher->encrypt_init = OSSL_FUNC_asym_cipher_encrypt_init(fns);
              encfncnt++;
              break;
          case OSSL_FUNC_ASYM_CIPHER_ENCRYPT:
              if (cipher->encrypt != NULL)
                  break;
              cipher->encrypt = OSSL_FUNC_asym_cipher_encrypt(fns);
              encfncnt++;
              break;
          case OSSL_FUNC_ASYM_CIPHER_DECRYPT_INIT:
              if (cipher->decrypt_init != NULL)
                  break;
              cipher->decrypt_init = OSSL_FUNC_asym_cipher_decrypt_init(fns);
              decfncnt++;
              break;
          case OSSL_FUNC_ASYM_CIPHER_DECRYPT:
              if (cipher->decrypt != NULL)
                  break;
              cipher->decrypt = OSSL_FUNC_asym_cipher_decrypt(fns);
              decfncnt++;
              break;
          case OSSL_FUNC_ASYM_CIPHER_FREECTX:
              if (cipher->freectx != NULL)
                  break;
              cipher->freectx = OSSL_FUNC_asym_cipher_freectx(fns);
              ctxfncnt++;
              break;
          case OSSL_FUNC_ASYM_CIPHER_DUPCTX:
              if (cipher->dupctx != NULL)
                  break;
              cipher->dupctx = OSSL_FUNC_asym_cipher_dupctx(fns);
              break;
          case OSSL_FUNC_ASYM_CIPHER_GET_CTX_PARAMS:
              if (cipher->get_ctx_params != NULL)
                  break;
              cipher->get_ctx_params
                  = OSSL_FUNC_asym_cipher_get_ctx_params(fns);
              gparamfncnt++;
              break;
          case OSSL_FUNC_ASYM_CIPHER_GETTABLE_CTX_PARAMS:
              if (cipher->gettable_ctx_params != NULL)
                  break;
              cipher->gettable_ctx_params
                  = OSSL_FUNC_asym_cipher_gettable_ctx_params(fns);
              gparamfncnt++;
              break;
          case OSSL_FUNC_ASYM_CIPHER_SET_CTX_PARAMS:
              if (cipher->set_ctx_params != NULL)
                  break;
              cipher->set_ctx_params
                  = OSSL_FUNC_asym_cipher_set_ctx_params(fns);
              sparamfncnt++;
              break;
          case OSSL_FUNC_ASYM_CIPHER_SETTABLE_CTX_PARAMS:
              if (cipher->settable_ctx_params != NULL)
                  break;
              cipher->settable_ctx_params
                  = OSSL_FUNC_asym_cipher_settable_ctx_params(fns);
              sparamfncnt++;
              break;
          }
      }
      if (ctxfncnt != 2
          || (encfncnt != 0 && encfncnt != 2)
          || (decfncnt != 0 && decfncnt != 2)
          || (encfncnt != 2 && decfncnt != 2)
          || (gparamfncnt != 0 && gparamfncnt != 2)
          || (sparamfncnt != 0 && sparamfncnt != 2)) {
          /*
           * In order to be a consistent set of functions we must have at least
           * a set of context functions (newctx and freectx) as well as a pair of
           * "cipher" functions: (encrypt_init, encrypt) or
           * (decrypt_init decrypt). set_ctx_params and settable_ctx_params are
           * optional, but if one of them is present then the other one must also
           * be present. The same applies to get_ctx_params and
           * gettable_ctx_params. The dupctx function is optional.
           */
          ERR_raise(ERR_LIB_EVP, EVP_R_INVALID_PROVIDER_FUNCTIONS);
          goto err;
      }
  
      return cipher;
   err:
      EVP_ASYM_CIPHER_free(cipher);
      return NULL;
  }
  
  void EVP_ASYM_CIPHER_free(EVP_ASYM_CIPHER *cipher)
  {
      if (cipher != NULL) {
          int i;
  
          CRYPTO_DOWN_REF(&cipher->refcnt, &i, cipher->lock);
          if (i > 0)
              return;
          ossl_provider_free(cipher->prov);
          CRYPTO_THREAD_lock_free(cipher->lock);
          OPENSSL_free(cipher);
      }
  }
  
  int EVP_ASYM_CIPHER_up_ref(EVP_ASYM_CIPHER *cipher)
  {
      int ref = 0;
  
      CRYPTO_UP_REF(&cipher->refcnt, &ref, cipher->lock);
      return 1;
  }
  
  OSSL_PROVIDER *EVP_ASYM_CIPHER_provider(const EVP_ASYM_CIPHER *cipher)
  {
      return cipher->prov;
  }
  
  EVP_ASYM_CIPHER *EVP_ASYM_CIPHER_fetch(OPENSSL_CTX *ctx, const char *algorithm,
                                         const char *properties)
  {
      return evp_generic_fetch(ctx, OSSL_OP_ASYM_CIPHER, algorithm, properties,
                               evp_asym_cipher_from_dispatch,
                               (int (*)(void *))EVP_ASYM_CIPHER_up_ref,
                               (void (*)(void *))EVP_ASYM_CIPHER_free);
  }
  
  int EVP_ASYM_CIPHER_is_a(const EVP_ASYM_CIPHER *cipher, const char *name)
  {
      return evp_is_a(cipher->prov, cipher->name_id, NULL, name);
  }
  
  int EVP_ASYM_CIPHER_number(const EVP_ASYM_CIPHER *cipher)
  {
      return cipher->name_id;
  }
  
  void EVP_ASYM_CIPHER_do_all_provided(OPENSSL_CTX *libctx,
                                       void (*fn)(EVP_ASYM_CIPHER *cipher,
                                                  void *arg),
                                       void *arg)
  {
      evp_generic_do_all(libctx, OSSL_OP_ASYM_CIPHER,
                         (void (*)(void *, void *))fn, arg,
                         evp_asym_cipher_from_dispatch,
                         (void (*)(void *))EVP_ASYM_CIPHER_free);
  }
  
  
  void EVP_ASYM_CIPHER_names_do_all(const EVP_ASYM_CIPHER *cipher,
                                    void (*fn)(const char *name, void *data),
                                    void *data)
  {
      if (cipher->prov != NULL)
          evp_names_do_all(cipher->prov, cipher->name_id, fn, data);
  }
  
  const OSSL_PARAM *EVP_ASYM_CIPHER_gettable_ctx_params(const EVP_ASYM_CIPHER *cip)
  {
      void *provctx;
  
      if (cip == NULL || cip->gettable_ctx_params == NULL)
          return NULL;
  
      provctx = ossl_provider_ctx(EVP_ASYM_CIPHER_provider(cip));
      return cip->gettable_ctx_params(provctx);
  }
  
  const OSSL_PARAM *EVP_ASYM_CIPHER_settable_ctx_params(const EVP_ASYM_CIPHER *cip)
  {
      void *provctx;
  
      if (cip == NULL || cip->settable_ctx_params == NULL)
          return NULL;
  
      provctx = ossl_provider_ctx(EVP_ASYM_CIPHER_provider(cip));
      return cip->settable_ctx_params(provctx);
  }
  