crypto/evp/p_seal.c

   1 /*
   2  * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #include <stdio.h>
  11 #include "internal/cryptlib.h"
  12 #include <openssl/rand.h>
  13 #include <openssl/rsa.h>
  14 #include <openssl/evp.h>
  15 #include <openssl/objects.h>
  16 #include <openssl/x509.h>
  17
  18 int EVP_SealInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type,
  19                  unsigned char **ek, int *ekl, unsigned char *iv,
  20                  EVP_PKEY **pubk, int npubk)
  21 {
  22     unsigned char key[EVP_MAX_KEY_LENGTH];
  23     int i;
  24     int rv = 0;
  25
  26     if (type) {
  27         EVP_CIPHER_CTX_reset(ctx);
  28         if (!EVP_EncryptInit_ex(ctx, type, NULL, NULL, NULL))
  29             return 0;
  30     }
  31     if ((npubk <= 0) || !pubk)
  32         return 1;
  33
  34     if (EVP_CIPHER_CTX_rand_key(ctx, key) <= 0)
  35         return 0;
  36
  37     if (EVP_CIPHER_CTX_iv_length(ctx)
  38             && RAND_bytes(iv, EVP_CIPHER_CTX_iv_length(ctx)) <= 0)
  39         goto err;
  40
  41     if (!EVP_EncryptInit_ex(ctx, NULL, NULL, key, iv))
  42         goto err;
  43
  44     for (i = 0; i < npubk; i++) {
  45         size_t keylen = EVP_CIPHER_CTX_key_length(ctx);
  46         EVP_PKEY_CTX *pctx = NULL;
  47
  48         if ((pctx = EVP_PKEY_CTX_new(pubk[i], NULL)) == NULL) {
  49             ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
  50             goto err;
  51         }
  52
  53         if (EVP_PKEY_encrypt_init(pctx) <= 0
  54             || EVP_PKEY_encrypt(pctx, ek[i], &keylen, key, keylen) <= 0)
  55             goto err;
  56         ekl[i] = (int)keylen;
  57         EVP_PKEY_CTX_free(pctx);
  58     }
  59     rv = npubk;
  60 err:
  61     OPENSSL_cleanse(key, sizeof(key));
  62     return rv;
  63 }
  64
  65 int EVP_SealFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
  66 {
  67     int i;
  68     i = EVP_EncryptFinal_ex(ctx, out, outl);
  69     if (i)
  70         i = EVP_EncryptInit_ex(ctx, NULL, NULL, NULL, NULL);
  71     return i;
  72 }