xref: /dragonfly/crypto/libressl/crypto/evp/evp_key.c (revision 6f5ec8b5)
1 /* $OpenBSD: evp_key.c,v 1.27 2021/12/12 21:30:13 tb Exp $ */
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 <string.h>
61 
62 #include <openssl/err.h>
63 #include <openssl/evp.h>
64 #include <openssl/objects.h>
65 #include <openssl/ui.h>
66 #include <openssl/x509.h>
67 
68 #include "evp_locl.h"
69 
70 /* should be init to zeros. */
71 static char prompt_string[80];
72 
73 void
74 EVP_set_pw_prompt(const char *prompt)
75 {
76 	if (prompt == NULL)
77 		prompt_string[0] = '\0';
78 	else {
79 		strlcpy(prompt_string, prompt, sizeof(prompt_string));
80 	}
81 }
82 
83 char *
84 EVP_get_pw_prompt(void)
85 {
86 	if (prompt_string[0] == '\0')
87 		return (NULL);
88 	else
89 		return (prompt_string);
90 }
91 
92 int
93 EVP_read_pw_string(char *buf, int len, const char *prompt, int verify)
94 {
95 	return EVP_read_pw_string_min(buf, 0, len, prompt, verify);
96 }
97 
98 int
99 EVP_read_pw_string_min(char *buf, int min, int len, const char *prompt,
100     int verify)
101 {
102 	int ret;
103 	char buff[BUFSIZ];
104 	UI *ui;
105 
106 	if (len > BUFSIZ)
107 		len = BUFSIZ;
108 	/* Ensure that 0 <= min <= len - 1. In particular, 1 <= len. */
109 	if (min < 0 || len - 1 < min)
110 		return -1;
111 	if ((prompt == NULL) && (prompt_string[0] != '\0'))
112 		prompt = prompt_string;
113 	ui = UI_new();
114 	if (ui == NULL)
115 		return -1;
116 	if (UI_add_input_string(ui, prompt, 0, buf, min, len - 1) < 0)
117 		return -1;
118 	if (verify) {
119 		if (UI_add_verify_string(ui, prompt, 0, buff, min, len - 1, buf)
120 		    < 0)
121 			return -1;
122 	}
123 	ret = UI_process(ui);
124 	UI_free(ui);
125 	explicit_bzero(buff, BUFSIZ);
126 	return ret;
127 }
128 
129 int
130 EVP_BytesToKey(const EVP_CIPHER *type, const EVP_MD *md,
131     const unsigned char *salt, const unsigned char *data, int datal,
132     int count, unsigned char *key, unsigned char *iv)
133 {
134 	EVP_MD_CTX c;
135 	unsigned char md_buf[EVP_MAX_MD_SIZE];
136 	int niv, nkey, addmd = 0;
137 	unsigned int mds = 0, i;
138 	int rv = 0;
139 
140 	nkey = type->key_len;
141 	niv = type->iv_len;
142 
143 	if ((size_t)nkey > EVP_MAX_KEY_LENGTH) {
144 		EVPerror(EVP_R_BAD_KEY_LENGTH);
145 		return 0;
146 	}
147 	if ((size_t)niv > EVP_MAX_IV_LENGTH) {
148 		EVPerror(EVP_R_IV_TOO_LARGE);
149 		return 0;
150 	}
151 
152 	if (data == NULL)
153 		return (nkey);
154 
155 	EVP_MD_CTX_init(&c);
156 	for (;;) {
157 		if (!EVP_DigestInit_ex(&c, md, NULL))
158 			goto err;
159 		if (addmd++)
160 			if (!EVP_DigestUpdate(&c, &(md_buf[0]), mds))
161 				goto err;
162 		if (!EVP_DigestUpdate(&c, data, datal))
163 			goto err;
164 		if (salt != NULL)
165 			if (!EVP_DigestUpdate(&c, salt, PKCS5_SALT_LEN))
166 				goto err;
167 		if (!EVP_DigestFinal_ex(&c, &(md_buf[0]), &mds))
168 			goto err;
169 
170 		for (i = 1; i < (unsigned int)count; i++) {
171 			if (!EVP_DigestInit_ex(&c, md, NULL))
172 				goto err;
173 			if (!EVP_DigestUpdate(&c, &(md_buf[0]), mds))
174 				goto err;
175 			if (!EVP_DigestFinal_ex(&c, &(md_buf[0]), &mds))
176 				goto err;
177 		}
178 		i = 0;
179 		if (nkey) {
180 			for (;;) {
181 				if (nkey == 0)
182 					break;
183 				if (i == mds)
184 					break;
185 				if (key != NULL)
186 					*(key++) = md_buf[i];
187 				nkey--;
188 				i++;
189 			}
190 		}
191 		if (niv && (i != mds)) {
192 			for (;;) {
193 				if (niv == 0)
194 					break;
195 				if (i == mds)
196 					break;
197 				if (iv != NULL)
198 					*(iv++) = md_buf[i];
199 				niv--;
200 				i++;
201 			}
202 		}
203 		if ((nkey == 0) && (niv == 0))
204 			break;
205 	}
206 	rv = type->key_len;
207 
208 err:
209 	EVP_MD_CTX_cleanup(&c);
210 	explicit_bzero(md_buf, sizeof md_buf);
211 	return rv;
212 }
213