text: /* 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/evp.h>
  
  #include <string.h>
  
  #include <openssl/digest.h>
  #include <openssl/err.h>
  #include <openssl/mem.h>
  
  #include "../internal.h"
  #include "internal.h"
  
  
  static const EVP_PKEY_METHOD *const evp_methods[] = {
    &rsa_pkey_meth,
    &ec_pkey_meth,
    &ed25519_pkey_meth,
  };
  
  static const EVP_PKEY_METHOD *evp_pkey_meth_find(int type) {
    unsigned i;
  
    for (i = 0; i < sizeof(evp_methods)/sizeof(EVP_PKEY_METHOD*); i++) {
      if (evp_methods[i]->pkey_id == type) {
        return evp_methods[i];
      }
    }
  
    return NULL;
  }
  
  static EVP_PKEY_CTX *evp_pkey_ctx_new(EVP_PKEY *pkey, ENGINE *e, int id) {
    EVP_PKEY_CTX *ret;
    const EVP_PKEY_METHOD *pmeth;
  
    if (id == -1) {
      if (!pkey || !pkey->ameth) {
        return NULL;
      }
      id = pkey->ameth->pkey_id;
    }
  
    pmeth = evp_pkey_meth_find(id);
  
    if (pmeth == NULL) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_UNSUPPORTED_ALGORITHM);
      ERR_add_error_dataf("algorithm %d", id);
      return NULL;
    }
  
    ret = OPENSSL_malloc(sizeof(EVP_PKEY_CTX));
    if (!ret) {
      OPENSSL_PUT_ERROR(EVP, ERR_R_MALLOC_FAILURE);
      return NULL;
    }
    OPENSSL_memset(ret, 0, sizeof(EVP_PKEY_CTX));
  
    ret->engine = e;
    ret->pmeth = pmeth;
    ret->operation = EVP_PKEY_OP_UNDEFINED;
  
    if (pkey) {
      EVP_PKEY_up_ref(pkey);
      ret->pkey = pkey;
    }
  
    if (pmeth->init) {
      if (pmeth->init(ret) <= 0) {
        EVP_PKEY_free(ret->pkey);
        OPENSSL_free(ret);
        return NULL;
      }
    }
  
    return ret;
  }
  
  EVP_PKEY_CTX *EVP_PKEY_CTX_new(EVP_PKEY *pkey, ENGINE *e) {
    return evp_pkey_ctx_new(pkey, e, -1);
  }
  
  EVP_PKEY_CTX *EVP_PKEY_CTX_new_id(int id, ENGINE *e) {
    return evp_pkey_ctx_new(NULL, e, id);
  }
  
  void EVP_PKEY_CTX_free(EVP_PKEY_CTX *ctx) {
    if (ctx == NULL) {
      return;
    }
    if (ctx->pmeth && ctx->pmeth->cleanup) {
      ctx->pmeth->cleanup(ctx);
    }
    EVP_PKEY_free(ctx->pkey);
    EVP_PKEY_free(ctx->peerkey);
    OPENSSL_free(ctx);
  }
  
  EVP_PKEY_CTX *EVP_PKEY_CTX_dup(EVP_PKEY_CTX *ctx) {
    if (!ctx->pmeth || !ctx->pmeth->copy) {
      return NULL;
    }
  
    EVP_PKEY_CTX *ret = OPENSSL_malloc(sizeof(EVP_PKEY_CTX));
    if (!ret) {
      return NULL;
    }
  
    OPENSSL_memset(ret, 0, sizeof(EVP_PKEY_CTX));
  
    ret->pmeth = ctx->pmeth;
    ret->engine = ctx->engine;
    ret->operation = ctx->operation;
  
    if (ctx->pkey != NULL) {
      EVP_PKEY_up_ref(ctx->pkey);
      ret->pkey = ctx->pkey;
    }
  
    if (ctx->peerkey != NULL) {
      EVP_PKEY_up_ref(ctx->peerkey);
      ret->peerkey = ctx->peerkey;
    }
  
    if (ctx->pmeth->copy(ret, ctx) <= 0) {
      ret->pmeth = NULL;
      EVP_PKEY_CTX_free(ret);
      OPENSSL_PUT_ERROR(EVP, ERR_LIB_EVP);
      return NULL;
    }
  
    return ret;
  }
  
  EVP_PKEY *EVP_PKEY_CTX_get0_pkey(EVP_PKEY_CTX *ctx) { return ctx->pkey; }
  
  int EVP_PKEY_CTX_ctrl(EVP_PKEY_CTX *ctx, int keytype, int optype, int cmd,
                        int p1, void *p2) {
    if (!ctx || !ctx->pmeth || !ctx->pmeth->ctrl) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_COMMAND_NOT_SUPPORTED);
      return 0;
    }
    if (keytype != -1 && ctx->pmeth->pkey_id != keytype) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
      return 0;
    }
  
    if (ctx->operation == EVP_PKEY_OP_UNDEFINED) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_NO_OPERATION_SET);
      return 0;
    }
  
    if (optype != -1 && !(ctx->operation & optype)) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_INVALID_OPERATION);
      return 0;
    }
  
    return ctx->pmeth->ctrl(ctx, cmd, p1, p2);
  }
  
  int EVP_PKEY_sign_init(EVP_PKEY_CTX *ctx) {
    if (ctx == NULL || ctx->pmeth == NULL ||
        (ctx->pmeth->sign == NULL && ctx->pmeth->sign_message == NULL)) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
      return 0;
    }
  
    ctx->operation = EVP_PKEY_OP_SIGN;
    return 1;
  }
  
  int EVP_PKEY_sign(EVP_PKEY_CTX *ctx, uint8_t *sig, size_t *sig_len,
                    const uint8_t *digest, size_t digest_len) {
    if (!ctx || !ctx->pmeth || !ctx->pmeth->sign) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
      return 0;
    }
    if (ctx->operation != EVP_PKEY_OP_SIGN) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATON_NOT_INITIALIZED);
      return 0;
    }
    return ctx->pmeth->sign(ctx, sig, sig_len, digest, digest_len);
  }
  
  int EVP_PKEY_verify_init(EVP_PKEY_CTX *ctx) {
    if (ctx == NULL || ctx->pmeth == NULL ||
        (ctx->pmeth->verify == NULL && ctx->pmeth->verify_message == NULL)) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
      return 0;
    }
    ctx->operation = EVP_PKEY_OP_VERIFY;
    return 1;
  }
  
  int EVP_PKEY_verify(EVP_PKEY_CTX *ctx, const uint8_t *sig, size_t sig_len,
                      const uint8_t *digest, size_t digest_len) {
    if (!ctx || !ctx->pmeth || !ctx->pmeth->verify) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
      return 0;
    }
    if (ctx->operation != EVP_PKEY_OP_VERIFY) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATON_NOT_INITIALIZED);
      return 0;
    }
    return ctx->pmeth->verify(ctx, sig, sig_len, digest, digest_len);
  }
  
  int EVP_PKEY_encrypt_init(EVP_PKEY_CTX *ctx) {
    if (!ctx || !ctx->pmeth || !ctx->pmeth->encrypt) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
      return 0;
    }
    ctx->operation = EVP_PKEY_OP_ENCRYPT;
    return 1;
  }
  
  int EVP_PKEY_encrypt(EVP_PKEY_CTX *ctx, uint8_t *out, size_t *outlen,
                       const uint8_t *in, size_t inlen) {
    if (!ctx || !ctx->pmeth || !ctx->pmeth->encrypt) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
      return 0;
    }
    if (ctx->operation != EVP_PKEY_OP_ENCRYPT) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATON_NOT_INITIALIZED);
      return 0;
    }
    return ctx->pmeth->encrypt(ctx, out, outlen, in, inlen);
  }
  
  int EVP_PKEY_decrypt_init(EVP_PKEY_CTX *ctx) {
    if (!ctx || !ctx->pmeth || !ctx->pmeth->decrypt) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
      return 0;
    }
    ctx->operation = EVP_PKEY_OP_DECRYPT;
    return 1;
  }
  
  int EVP_PKEY_decrypt(EVP_PKEY_CTX *ctx, uint8_t *out, size_t *outlen,
                       const uint8_t *in, size_t inlen) {
    if (!ctx || !ctx->pmeth || !ctx->pmeth->decrypt) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
      return 0;
    }
    if (ctx->operation != EVP_PKEY_OP_DECRYPT) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATON_NOT_INITIALIZED);
      return 0;
    }
    return ctx->pmeth->decrypt(ctx, out, outlen, in, inlen);
  }
  
  int EVP_PKEY_verify_recover_init(EVP_PKEY_CTX *ctx) {
    if (!ctx || !ctx->pmeth || !ctx->pmeth->verify_recover) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
      return 0;
    }
    ctx->operation = EVP_PKEY_OP_VERIFYRECOVER;
    return 1;
  }
  
  int EVP_PKEY_verify_recover(EVP_PKEY_CTX *ctx, uint8_t *out, size_t *out_len,
                              const uint8_t *sig, size_t sig_len) {
    if (!ctx || !ctx->pmeth || !ctx->pmeth->verify_recover) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
      return 0;
    }
    if (ctx->operation != EVP_PKEY_OP_VERIFYRECOVER) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATON_NOT_INITIALIZED);
      return 0;
    }
    return ctx->pmeth->verify_recover(ctx, out, out_len, sig, sig_len);
  }
  
  int EVP_PKEY_derive_init(EVP_PKEY_CTX *ctx) {
    if (!ctx || !ctx->pmeth || !ctx->pmeth->derive) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
      return 0;
    }
    ctx->operation = EVP_PKEY_OP_DERIVE;
    return 1;
  }
  
  int EVP_PKEY_derive_set_peer(EVP_PKEY_CTX *ctx, EVP_PKEY *peer) {
    int ret;
    if (!ctx || !ctx->pmeth ||
        !(ctx->pmeth->derive || ctx->pmeth->encrypt || ctx->pmeth->decrypt) ||
        !ctx->pmeth->ctrl) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
      return 0;
    }
    if (ctx->operation != EVP_PKEY_OP_DERIVE &&
        ctx->operation != EVP_PKEY_OP_ENCRYPT &&
        ctx->operation != EVP_PKEY_OP_DECRYPT) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATON_NOT_INITIALIZED);
      return 0;
    }
  
    ret = ctx->pmeth->ctrl(ctx, EVP_PKEY_CTRL_PEER_KEY, 0, peer);
  
    if (ret <= 0) {
      return 0;
    }
  
    if (ret == 2) {
      return 1;
    }
  
    if (!ctx->pkey) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_NO_KEY_SET);
      return 0;
    }
  
    if (ctx->pkey->type != peer->type) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_DIFFERENT_KEY_TYPES);
      return 0;
    }
  
    // ran@cryptocom.ru: For clarity.  The error is if parameters in peer are
    // present (!missing) but don't match.  EVP_PKEY_cmp_parameters may return
    // 1 (match), 0 (don't match) and -2 (comparison is not defined).  -1
    // (different key types) is impossible here because it is checked earlier.
    // -2 is OK for us here, as well as 1, so we can check for 0 only.
    if (!EVP_PKEY_missing_parameters(peer) &&
        !EVP_PKEY_cmp_parameters(ctx->pkey, peer)) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_DIFFERENT_PARAMETERS);
      return 0;
    }
  
    EVP_PKEY_free(ctx->peerkey);
    ctx->peerkey = peer;
  
    ret = ctx->pmeth->ctrl(ctx, EVP_PKEY_CTRL_PEER_KEY, 1, peer);
  
    if (ret <= 0) {
      ctx->peerkey = NULL;
      return 0;
    }
  
    EVP_PKEY_up_ref(peer);
    return 1;
  }
  
  int EVP_PKEY_derive(EVP_PKEY_CTX *ctx, uint8_t *key, size_t *out_key_len) {
    if (!ctx || !ctx->pmeth || !ctx->pmeth->derive) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
      return 0;
    }
    if (ctx->operation != EVP_PKEY_OP_DERIVE) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATON_NOT_INITIALIZED);
      return 0;
    }
    return ctx->pmeth->derive(ctx, key, out_key_len);
  }
  
  int EVP_PKEY_keygen_init(EVP_PKEY_CTX *ctx) {
    if (!ctx || !ctx->pmeth || !ctx->pmeth->keygen) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
      return 0;
    }
    ctx->operation = EVP_PKEY_OP_KEYGEN;
    return 1;
  }
  
  int EVP_PKEY_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY **ppkey) {
    if (!ctx || !ctx->pmeth || !ctx->pmeth->keygen) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
      return 0;
    }
    if (ctx->operation != EVP_PKEY_OP_KEYGEN) {
      OPENSSL_PUT_ERROR(EVP, EVP_R_OPERATON_NOT_INITIALIZED);
      return 0;
    }
  
    if (!ppkey) {
      return 0;
    }
  
    if (!*ppkey) {
      *ppkey = EVP_PKEY_new();
      if (!*ppkey) {
        OPENSSL_PUT_ERROR(EVP, ERR_LIB_EVP);
        return 0;
      }
    }
  
    if (!ctx->pmeth->keygen(ctx, *ppkey)) {
      EVP_PKEY_free(*ppkey);
      *ppkey = NULL;
      return 0;
    }
    return 1;
  }
  