evp_key.c revision 59191 
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 "cryptlib.h"
61#include <openssl/x509.h>
62#include <openssl/objects.h>
63#include <openssl/evp.h>
64
65/* should be init to zeros. */
66static char prompt_string[80];
67
68void EVP_set_pw_prompt(char *prompt)
69	{
70	if (prompt == NULL)
71		prompt_string[0]='\0';
72	else
73		strncpy(prompt_string,prompt,79);
74	}
75
76char *EVP_get_pw_prompt(void)
77	{
78	if (prompt_string[0] == '\0')
79		return(NULL);
80	else
81		return(prompt_string);
82	}
83
84/* For historical reasons, the standard function for reading passwords is
85 * in the DES library -- if someone ever wants to disable DES,
86 * this function will fail */
87int EVP_read_pw_string(char *buf, int len, const char *prompt, int verify)
88	{
89#ifndef NO_DES
90	if ((prompt == NULL) && (prompt_string[0] != '\0'))
91		prompt=prompt_string;
92	return(des_read_pw_string(buf,len,prompt,verify));
93#else
94	return -1;
95#endif
96	}
97
98int EVP_BytesToKey(const EVP_CIPHER *type, EVP_MD *md, unsigned char *salt,
99	     unsigned char *data, int datal, int count, unsigned char *key,
100	     unsigned char *iv)
101	{
102	EVP_MD_CTX c;
103	unsigned char md_buf[EVP_MAX_MD_SIZE];
104	int niv,nkey,addmd=0;
105	unsigned int mds=0,i;
106
107	nkey=type->key_len;
108	niv=type->iv_len;
109
110	if (data == NULL) return(nkey);
111
112	for (;;)
113		{
114		EVP_DigestInit(&c,md);
115		if (addmd++)
116			EVP_DigestUpdate(&c,&(md_buf[0]),mds);
117		EVP_DigestUpdate(&c,data,datal);
118		if (salt != NULL)
119			EVP_DigestUpdate(&c,salt,8);
120		EVP_DigestFinal(&c,&(md_buf[0]),&mds);
121
122		for (i=1; i<(unsigned int)count; i++)
123			{
124			EVP_DigestInit(&c,md);
125			EVP_DigestUpdate(&c,&(md_buf[0]),mds);
126			EVP_DigestFinal(&c,&(md_buf[0]),&mds);
127			}
128		i=0;
129		if (nkey)
130			{
131			for (;;)
132				{
133				if (nkey == 0) break;
134				if (i == mds) break;
135				if (key != NULL)
136					*(key++)=md_buf[i];
137				nkey--;
138				i++;
139				}
140			}
141		if (niv && (i != mds))
142			{
143			for (;;)
144				{
145				if (niv == 0) break;
146				if (i == mds) break;
147				if (iv != NULL)
148					*(iv++)=md_buf[i];
149				niv--;
150				i++;
151				}
152			}
153		if ((nkey == 0) && (niv == 0)) break;
154		}
155	memset(&c,0,sizeof(c));
156	memset(&(md_buf[0]),0,EVP_MAX_MD_SIZE);
157	return(type->key_len);
158	}
159
160