1/*
2 * Copyright 1995-2021 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/x509.h>
13#include <openssl/objects.h>
14#include <openssl/evp.h>
15#include <openssl/ui.h>
16
17#ifndef BUFSIZ
18# define BUFSIZ 256
19#endif
20
21/* should be init to zeros. */
22static char prompt_string[80];
23
24void EVP_set_pw_prompt(const char *prompt)
25{
26    if (prompt == NULL)
27        prompt_string[0] = '\0';
28    else {
29        strncpy(prompt_string, prompt, 79);
30        prompt_string[79] = '\0';
31    }
32}
33
34char *EVP_get_pw_prompt(void)
35{
36    if (prompt_string[0] == '\0')
37        return NULL;
38    else
39        return prompt_string;
40}
41
42/*
43 * For historical reasons, the standard function for reading passwords is in
44 * the DES library -- if someone ever wants to disable DES, this function
45 * will fail
46 */
47int EVP_read_pw_string(char *buf, int len, const char *prompt, int verify)
48{
49    return EVP_read_pw_string_min(buf, 0, len, prompt, verify);
50}
51
52int EVP_read_pw_string_min(char *buf, int min, int len, const char *prompt,
53                           int verify)
54{
55    int ret = -1;
56    char buff[BUFSIZ];
57    UI *ui;
58
59    if ((prompt == NULL) && (prompt_string[0] != '\0'))
60        prompt = prompt_string;
61    ui = UI_new();
62    if (ui == NULL)
63        return ret;
64    if (UI_add_input_string(ui, prompt, 0, buf, min,
65                            (len >= BUFSIZ) ? BUFSIZ - 1 : len) < 0
66        || (verify
67            && UI_add_verify_string(ui, prompt, 0, buff, min,
68                                    (len >= BUFSIZ) ? BUFSIZ - 1 : len,
69                                    buf) < 0))
70        goto end;
71    ret = UI_process(ui);
72    OPENSSL_cleanse(buff, BUFSIZ);
73 end:
74    UI_free(ui);
75    return ret;
76}
77
78int EVP_BytesToKey(const EVP_CIPHER *type, const EVP_MD *md,
79                   const unsigned char *salt, const unsigned char *data,
80                   int datal, int count, unsigned char *key,
81                   unsigned char *iv)
82{
83    EVP_MD_CTX *c;
84    unsigned char md_buf[EVP_MAX_MD_SIZE];
85    int niv, nkey, addmd = 0;
86    unsigned int mds = 0, i;
87    int rv = 0;
88    nkey = EVP_CIPHER_get_key_length(type);
89    niv = EVP_CIPHER_get_iv_length(type);
90    OPENSSL_assert(nkey <= EVP_MAX_KEY_LENGTH);
91    OPENSSL_assert(niv <= EVP_MAX_IV_LENGTH);
92
93    if (data == NULL)
94        return nkey;
95
96    c = EVP_MD_CTX_new();
97    if (c == NULL)
98        goto err;
99    for (;;) {
100        if (!EVP_DigestInit_ex(c, md, NULL))
101            goto err;
102        if (addmd++)
103            if (!EVP_DigestUpdate(c, &(md_buf[0]), mds))
104                goto err;
105        if (!EVP_DigestUpdate(c, data, datal))
106            goto err;
107        if (salt != NULL)
108            if (!EVP_DigestUpdate(c, salt, PKCS5_SALT_LEN))
109                goto err;
110        if (!EVP_DigestFinal_ex(c, &(md_buf[0]), &mds))
111            goto err;
112
113        for (i = 1; i < (unsigned int)count; i++) {
114            if (!EVP_DigestInit_ex(c, md, NULL))
115                goto err;
116            if (!EVP_DigestUpdate(c, &(md_buf[0]), mds))
117                goto err;
118            if (!EVP_DigestFinal_ex(c, &(md_buf[0]), &mds))
119                goto err;
120        }
121        i = 0;
122        if (nkey) {
123            for (;;) {
124                if (nkey == 0)
125                    break;
126                if (i == mds)
127                    break;
128                if (key != NULL)
129                    *(key++) = md_buf[i];
130                nkey--;
131                i++;
132            }
133        }
134        if (niv && (i != mds)) {
135            for (;;) {
136                if (niv == 0)
137                    break;
138                if (i == mds)
139                    break;
140                if (iv != NULL)
141                    *(iv++) = md_buf[i];
142                niv--;
143                i++;
144            }
145        }
146        if ((nkey == 0) && (niv == 0))
147            break;
148    }
149    rv = EVP_CIPHER_get_key_length(type);
150 err:
151    EVP_MD_CTX_free(c);
152    OPENSSL_cleanse(md_buf, sizeof(md_buf));
153    return rv;
154}
155