xref: /freebsd/crypto/openssl/crypto/evp/evp_key.c (revision f25b8c9fb4f58cf61adb47d7570abe7caa6d385d)
1 /*
2  * Copyright 1995-2024 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. */
22 static char prompt_string[80];
23 
EVP_set_pw_prompt(const char * prompt)24 void 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 
EVP_get_pw_prompt(void)34 char *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  */
EVP_read_pw_string(char * buf,int len,const char * prompt,int verify)47 int 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 
EVP_read_pw_string_min(char * buf,int min,int len,const char * prompt,int verify)52 int 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)
66             < 0
67         || (verify
68             && UI_add_verify_string(ui, prompt, 0, buff, min,
69                    (len >= BUFSIZ) ? BUFSIZ - 1 : len,
70                    buf)
71                 < 0))
72         goto end;
73     ret = UI_process(ui);
74     OPENSSL_cleanse(buff, BUFSIZ);
75 end:
76     UI_free(ui);
77     return ret;
78 }
79 
EVP_BytesToKey(const EVP_CIPHER * type,const EVP_MD * md,const unsigned char * salt,const unsigned char * data,int datal,int count,unsigned char * key,unsigned char * iv)80 int EVP_BytesToKey(const EVP_CIPHER *type, const EVP_MD *md,
81     const unsigned char *salt, const unsigned char *data,
82     int datal, int count, unsigned char *key,
83     unsigned char *iv)
84 {
85     EVP_MD_CTX *c;
86     unsigned char md_buf[EVP_MAX_MD_SIZE];
87     int niv, nkey, addmd = 0;
88     unsigned int mds = 0, i;
89     int rv = 0;
90     nkey = EVP_CIPHER_get_key_length(type);
91     niv = EVP_CIPHER_get_iv_length(type);
92     OPENSSL_assert(nkey <= EVP_MAX_KEY_LENGTH);
93     OPENSSL_assert(niv >= 0 && niv <= EVP_MAX_IV_LENGTH);
94 
95     if (data == NULL)
96         return nkey;
97 
98     c = EVP_MD_CTX_new();
99     if (c == NULL)
100         goto err;
101     for (;;) {
102         if (!EVP_DigestInit_ex(c, md, NULL))
103             goto err;
104         if (addmd++)
105             if (!EVP_DigestUpdate(c, &(md_buf[0]), mds))
106                 goto err;
107         if (!EVP_DigestUpdate(c, data, datal))
108             goto err;
109         if (salt != NULL)
110             if (!EVP_DigestUpdate(c, salt, PKCS5_SALT_LEN))
111                 goto err;
112         if (!EVP_DigestFinal_ex(c, &(md_buf[0]), &mds))
113             goto err;
114 
115         for (i = 1; i < (unsigned int)count; i++) {
116             if (!EVP_DigestInit_ex(c, md, NULL))
117                 goto err;
118             if (!EVP_DigestUpdate(c, &(md_buf[0]), mds))
119                 goto err;
120             if (!EVP_DigestFinal_ex(c, &(md_buf[0]), &mds))
121                 goto err;
122         }
123         i = 0;
124         if (nkey) {
125             for (;;) {
126                 if (nkey == 0)
127                     break;
128                 if (i == mds)
129                     break;
130                 if (key != NULL)
131                     *(key++) = md_buf[i];
132                 nkey--;
133                 i++;
134             }
135         }
136         if (niv && (i != mds)) {
137             for (;;) {
138                 if (niv == 0)
139                     break;
140                 if (i == mds)
141                     break;
142                 if (iv != NULL)
143                     *(iv++) = md_buf[i];
144                 niv--;
145                 i++;
146             }
147         }
148         if ((nkey == 0) && (niv == 0))
149             break;
150     }
151     rv = EVP_CIPHER_get_key_length(type);
152 err:
153     EVP_MD_CTX_free(c);
154     OPENSSL_cleanse(md_buf, sizeof(md_buf));
155     return rv;
156 }
157