crypto/evp/evp_key.c

   1 /* crypto/evp/evp_key.c */
   2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
   3  * All rights reserved.
   4  *
   5  * This package is an SSL implementation written
   6  * by Eric Young (eay@cryptsoft.com).
   7  * The implementation was written so as to conform with Netscapes SSL.
   8  *
   9  * This library is free for commercial and non-commercial use as long as
  10  * the following conditions are aheared to.  The following conditions
  11  * apply to all code found in this distribution, be it the RC4, RSA,
  12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  13  * included with this distribution is covered by the same copyright terms
  14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  15  *
  16  * Copyright remains Eric Young's, and as such any Copyright notices in
  17  * the code are not to be removed.
  18  * If this package is used in a product, Eric Young should be given attribution
  19  * as the author of the parts of the library used.
  20  * This can be in the form of a textual message at program startup or
  21  * in documentation (online or textual) provided with the package.
  22  *
  23  * Redistribution and use in source and binary forms, with or without
  24  * modification, are permitted provided that the following conditions
  25  * are met:
  26  * 1. Redistributions of source code must retain the copyright
  27  *    notice, this list of conditions and the following disclaimer.
  28  * 2. Redistributions in binary form must reproduce the above copyright
  29  *    notice, this list of conditions and the following disclaimer in the
  30  *    documentation and/or other materials provided with the distribution.
  31  * 3. All advertising materials mentioning features or use of this software
  32  *    must display the following acknowledgement:
  33  *    "This product includes cryptographic software written by
  34  *     Eric Young (eay@cryptsoft.com)"
  35  *    The word 'cryptographic' can be left out if the rouines from the library
  36  *    being used are not cryptographic related :-).
  37  * 4. If you include any Windows specific code (or a derivative thereof) from
  38  *    the apps directory (application code) you must include an acknowledgement:
  39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  40  *
  41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  51  * SUCH DAMAGE.
  52  *
  53  * The licence and distribution terms for any publically available version or
  54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
  55  * copied and put under another distribution licence
  56  * [including the GNU Public Licence.]
  57  */
  58
  59 #include <stdio.h>
  60 #include "internal/cryptlib.h"
  61 #include <openssl/x509.h>
  62 #include <openssl/objects.h>
  63 #include <openssl/evp.h>
  64 #include <openssl/ui.h>
  65
  66 /* should be init to zeros. */
  67 static char prompt_string[80];
  68
  69 void EVP_set_pw_prompt(const char *prompt)
  70 {
  71     if (prompt == NULL)
  72         prompt_string[0] = '\0';
  73     else {
  74         strncpy(prompt_string, prompt, 79);
  75         prompt_string[79] = '\0';
  76     }
  77 }
  78
  79 char *EVP_get_pw_prompt(void)
  80 {
  81     if (prompt_string[0] == '\0')
  82         return (NULL);
  83     else
  84         return (prompt_string);
  85 }
  86
  87 /*
  88  * For historical reasons, the standard function for reading passwords is in
  89  * the DES library -- if someone ever wants to disable DES, this function
  90  * will fail
  91  */
  92 int EVP_read_pw_string(char *buf, int len, const char *prompt, int verify)
  93 {
  94     return EVP_read_pw_string_min(buf, 0, len, prompt, verify);
  95 }
  96
  97 int EVP_read_pw_string_min(char *buf, int min, int len, const char *prompt,
  98                            int verify)
  99 {
 100     int ret;
 101     char buff[BUFSIZ];
 102     UI *ui;
 103
 104     if ((prompt == NULL) && (prompt_string[0] != '\0'))
 105         prompt = prompt_string;
 106     ui = UI_new();
 107     if (ui == NULL)
 108         return -1;
 109     UI_add_input_string(ui, prompt, 0, buf, min,
 110                         (len >= BUFSIZ) ? BUFSIZ - 1 : len);
 111     if (verify)
 112         UI_add_verify_string(ui, prompt, 0,
 113                              buff, min, (len >= BUFSIZ) ? BUFSIZ - 1 : len,
 114                              buf);
 115     ret = UI_process(ui);
 116     UI_free(ui);
 117     OPENSSL_cleanse(buff, BUFSIZ);
 118     return ret;
 119 }
 120
 121 int EVP_BytesToKey(const EVP_CIPHER *type, const EVP_MD *md,
 122                    const unsigned char *salt, const unsigned char *data,
 123                    int datal, int count, unsigned char *key,
 124                    unsigned char *iv)
 125 {
 126     EVP_MD_CTX c;
 127     unsigned char md_buf[EVP_MAX_MD_SIZE];
 128     int niv, nkey, addmd = 0;
 129     unsigned int mds = 0, i;
 130     int rv = 0;
 131     nkey = type->key_len;
 132     niv = type->iv_len;
 133     OPENSSL_assert(nkey <= EVP_MAX_KEY_LENGTH);
 134     OPENSSL_assert(niv <= EVP_MAX_IV_LENGTH);
 135
 136     if (data == NULL)
 137         return (nkey);
 138
 139     EVP_MD_CTX_init(&c);
 140     for (;;) {
 141         if (!EVP_DigestInit_ex(&c, md, NULL))
 142             goto err;
 143         if (addmd++)
 144             if (!EVP_DigestUpdate(&c, &(md_buf[0]), mds))
 145                 goto err;
 146         if (!EVP_DigestUpdate(&c, data, datal))
 147             goto err;
 148         if (salt != NULL)
 149             if (!EVP_DigestUpdate(&c, salt, PKCS5_SALT_LEN))
 150                 goto err;
 151         if (!EVP_DigestFinal_ex(&c, &(md_buf[0]), &mds))
 152             goto err;
 153
 154         for (i = 1; i < (unsigned int)count; i++) {
 155             if (!EVP_DigestInit_ex(&c, md, NULL))
 156                 goto err;
 157             if (!EVP_DigestUpdate(&c, &(md_buf[0]), mds))
 158                 goto err;
 159             if (!EVP_DigestFinal_ex(&c, &(md_buf[0]), &mds))
 160                 goto err;
 161         }
 162         i = 0;
 163         if (nkey) {
 164             for (;;) {
 165                 if (nkey == 0)
 166                     break;
 167                 if (i == mds)
 168                     break;
 169                 if (key != NULL)
 170                     *(key++) = md_buf[i];
 171                 nkey--;
 172                 i++;
 173             }
 174         }
 175         if (niv && (i != mds)) {
 176             for (;;) {
 177                 if (niv == 0)
 178                     break;
 179                 if (i == mds)
 180                     break;
 181                 if (iv != NULL)
 182                     *(iv++) = md_buf[i];
 183                 niv--;
 184                 i++;
 185             }
 186         }
 187         if ((nkey == 0) && (niv == 0))
 188             break;
 189     }
 190     rv = type->key_len;
 191  err:
 192     EVP_MD_CTX_cleanup(&c);
 193     OPENSSL_cleanse(md_buf, sizeof(md_buf));
 194     return rv;
 195 }