evp_key.c revision 109998 
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#include <openssl/ui.h>
65
66/* should be init to zeros. */
67static char prompt_string[80];
68
69void EVP_set_pw_prompt(char *prompt)
70	{
71	if (prompt == NULL)
72		prompt_string[0]='\0';
73	else
74		{
75		strncpy(prompt_string,prompt,79);
76		prompt_string[79]='\0';
77		}
78	}
79
80char *EVP_get_pw_prompt(void)
81	{
82	if (prompt_string[0] == '\0')
83		return(NULL);
84	else
85		return(prompt_string);
86	}
87
88/* For historical reasons, the standard function for reading passwords is
89 * in the DES library -- if someone ever wants to disable DES,
90 * this function will fail */
91int EVP_read_pw_string(char *buf, int len, const char *prompt, int verify)
92	{
93	int ret;
94	char buff[BUFSIZ];
95	UI *ui;
96
97	if ((prompt == NULL) && (prompt_string[0] != '\0'))
98		prompt=prompt_string;
99	ui = UI_new();
100	UI_add_input_string(ui,prompt,0,buf,0,(len>=BUFSIZ)?BUFSIZ-1:len);
101	if (verify)
102		UI_add_verify_string(ui,prompt,0,
103			buff,0,(len>=BUFSIZ)?BUFSIZ-1:len,buf);
104	ret = UI_process(ui);
105	UI_free(ui);
106	OPENSSL_cleanse(buff,BUFSIZ);
107	return ret;
108	}
109
110int EVP_BytesToKey(const EVP_CIPHER *type, const EVP_MD *md,
111	     const unsigned char *salt, const unsigned char *data, int datal,
112	     int count, unsigned char *key, unsigned char *iv)
113	{
114	EVP_MD_CTX c;
115	unsigned char md_buf[EVP_MAX_MD_SIZE];
116	int niv,nkey,addmd=0;
117	unsigned int mds=0,i;
118
119	nkey=type->key_len;
120	niv=type->iv_len;
121	OPENSSL_assert(nkey <= EVP_MAX_KEY_LENGTH);
122	OPENSSL_assert(niv <= EVP_MAX_IV_LENGTH);
123
124	if (data == NULL) return(nkey);
125
126	EVP_MD_CTX_init(&c);
127	for (;;)
128		{
129		EVP_DigestInit_ex(&c,md, NULL);
130		if (addmd++)
131			EVP_DigestUpdate(&c,&(md_buf[0]),mds);
132		EVP_DigestUpdate(&c,data,datal);
133		if (salt != NULL)
134			EVP_DigestUpdate(&c,salt,PKCS5_SALT_LEN);
135		EVP_DigestFinal_ex(&c,&(md_buf[0]),&mds);
136
137		for (i=1; i<(unsigned int)count; i++)
138			{
139			EVP_DigestInit_ex(&c,md, NULL);
140			EVP_DigestUpdate(&c,&(md_buf[0]),mds);
141			EVP_DigestFinal_ex(&c,&(md_buf[0]),&mds);
142			}
143		i=0;
144		if (nkey)
145			{
146			for (;;)
147				{
148				if (nkey == 0) break;
149				if (i == mds) break;
150				if (key != NULL)
151					*(key++)=md_buf[i];
152				nkey--;
153				i++;
154				}
155			}
156		if (niv && (i != mds))
157			{
158			for (;;)
159				{
160				if (niv == 0) break;
161				if (i == mds) break;
162				if (iv != NULL)
163					*(iv++)=md_buf[i];
164				niv--;
165				i++;
166				}
167			}
168		if ((nkey == 0) && (niv == 0)) break;
169		}
170	EVP_MD_CTX_cleanup(&c);
171	OPENSSL_cleanse(&(md_buf[0]),EVP_MAX_MD_SIZE);
172	return(type->key_len);
173	}
174
175