1 /*
2 * FreeSec: libcrypt for NetBSD
3 *
4 * Copyright (c) 1994 David Burren
5 * All rights reserved.
6 *
7 * Adapted for FreeBSD-2.0 by Geoffrey M. Rehmet
8 * this file should now *only* export crypt(), in order to make
9 * binaries of libcrypt exportable from the USA
10 *
11 * Adapted for FreeBSD-4.0 by Mark R V Murray
12 * this file should now *only* export crypt_des(), in order to make
13 * a module that can be optionally included in libcrypt.
14 *
15 * Adapted for libxcrypt by Zack Weinberg, 2017
16 * see notes in des.c
17 *
18 * Adapted for libxcrypt by Björn Esser, 2019
19 * add function-stubs simply setting error to ENOSYS.
20 *
21 * Redistribution and use in source and binary forms, with or without
22 * modification, are permitted provided that the following conditions
23 * are met:
24 * 1. Redistributions of source code must retain the above copyright
25 * notice, this list of conditions and the following disclaimer.
26 * 2. Redistributions in binary form must reproduce the above copyright
27 * notice, this list of conditions and the following disclaimer in the
28 * documentation and/or other materials provided with the distribution.
29 * 3. Neither the name of the author nor the names of other contributors
30 * may be used to endorse or promote products derived from this software
31 * without specific prior written permission.
32 *
33 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
34 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
35 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
36 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
37 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
38 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
39 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
40 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
41 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
42 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
43 * SUCH DAMAGE.
44 *
45 * This is an original implementation of the DES and the crypt(3) interfaces
46 * by David Burren <davidb@werj.com.au>.
47 */
48
49 /* Obsolete DES symmetric cipher API - not to be used in new code. */
50
51 #include "crypt-port.h"
52 #include "crypt-obsolete.h"
53 #include "alg-des.h"
54 #include <errno.h>
55
56 #if (INCLUDE_encrypt || INCLUDE_encrypt_r || INCLUDE_setkey || INCLUDE_setkey_r) && \
57 !ENABLE_OBSOLETE_API_ENOSYS
58
59 static_assert(sizeof (struct des_ctx) + alignof (struct des_ctx)
60 <= CRYPT_DATA_INTERNAL_SIZE,
61 "crypt_data.internal is too small for struct des_ctx");
62
63 /* struct crypt_data is allocated by application code and contains
64 only char-typed fields, so its 'internal' field may not be
65 sufficiently aligned. */
66 static inline struct des_ctx *
67 get_des_ctx (struct crypt_data *data)
68 {
69 uintptr_t internalp = (uintptr_t) data->internal;
70 const uintptr_t align = alignof (struct des_ctx);
71 internalp = (internalp + align - 1) & ~(align - 1);
72 return (struct des_ctx *)internalp;
73 }
74
75 /* For reasons lost in the mists of time, these functions operate on
76 64-*byte* arrays, each of which should be either 0 or 1 - only the
77 low bit of each byte is examined. The DES primitives, much more
78 sensibly, operate on 8-byte/64-*bit* arrays. */
79
80 static void
81 unpack_bits (char bytev[64], const unsigned char bitv[8])
82 {
83 unsigned char c;
84 for (int i = 0; i < 8; i++)
85 {
86 c = bitv[i];
87 for (int j = 0; j < 8; j++)
88 bytev[i*8 + j] = (char)((c & (0x01 << (7 - j))) != 0);
89 }
90 }
91
92 static void
93 pack_bits (unsigned char bitv[8], const char bytev[64])
94 {
95 unsigned int c;
96 for (int i = 0; i < 8; i++)
97 {
98 c = 0;
99 for (int j = 0; j < 8; j++)
100 {
101 c <<= 1;
102 c |= ((unsigned char)bytev[i*8 + j] & 0x01u);
103 }
104 bitv[i] = (unsigned char)c;
105 }
106 }
107 #endif
108
109 /* Initialize DATA with a DES key, KEY, represented as a byte vector. */
110 #if (INCLUDE_setkey_r || INCLUDE_setkey) && !ENABLE_OBSOLETE_API_ENOSYS
111 static void
112 do_setkey_r (const char *key, struct des_ctx *ctx)
113 {
114 memset (ctx, 0, sizeof (struct des_ctx));
115 des_set_salt (ctx, 0);
116
117 unsigned char bkey[8];
118 pack_bits (bkey, key);
119 des_set_key (ctx, bkey);
120 }
121 #endif
122
123 #if INCLUDE_setkey_r
124 void
125 setkey_r (ARG_UNUSED (const char *key), ARG_UNUSED (struct crypt_data *data))
126 {
127 #if ENABLE_OBSOLETE_API_ENOSYS
128 /* This function is not supported in this configuration. */
129 errno = ENOSYS;
130 #else
131 do_setkey_r (key, get_des_ctx (data));
132 #endif
133 }
134 SYMVER_setkey_r;
135 #endif
136
137 /* Encrypt or decrypt one DES block, BLOCK, using the key schedule in
138 DATA. BLOCK is processed in place. */
139 #if (INCLUDE_encrypt_r || INCLUDE_encrypt) && !ENABLE_OBSOLETE_API_ENOSYS
140 static void
141 do_encrypt_r (char *block, int edflag, struct des_ctx *ctx)
142 {
143 unsigned char bin[8], bout[8];
144 pack_bits (bin, block);
145 des_crypt_block (ctx, bout, bin, 1, edflag != 0);
146 unpack_bits (block, bout);
147 }
148 #endif
149
150 #if INCLUDE_encrypt_r
151 void
152 encrypt_r (char *block, ARG_UNUSED (int edflag),
153 ARG_UNUSED (struct crypt_data *data))
154 {
155 #if ENABLE_OBSOLETE_API_ENOSYS
156 /* Make sure sensitive data is erased in case
157 case get_random_bytes() fails. */
158 explicit_bzero(block, 64);
159
160 /* Overwrite sensitive data with random data. */
161 get_random_bytes(block, 64);
162
163 /* This function is not supported in this configuration. */
164 errno = ENOSYS;
165 #else
166 do_encrypt_r (block, edflag, get_des_ctx (data));
167 #endif
168 }
169 SYMVER_encrypt_r;
170 #endif
171
172 /* Even-more-deprecated-than-the-above nonreentrant versions.
173 These use a separate state object from the main library's
174 nonreentrant crypt(). Unlike with crypt() vs crypt_r(),
175 these do not get their own file because they're not compiled
176 into the static library anyway. */
177
178 #if (INCLUDE_setkey || INCLUDE_encrypt) && !ENABLE_OBSOLETE_API_ENOSYS
179 static struct des_ctx nr_encrypt_ctx;
180 #endif
181
182 #if INCLUDE_setkey
183 void
184 setkey (ARG_UNUSED (const char *key))
185 {
186 #if ENABLE_OBSOLETE_API_ENOSYS
187 /* This function is not supported in this configuration. */
188 errno = ENOSYS;
189 #else
190 do_setkey_r (key, &nr_encrypt_ctx);
191 #endif
192 }
193 SYMVER_setkey;
194 #endif
195
196 #if INCLUDE_encrypt
197 void
198 encrypt (char *block, ARG_UNUSED (int edflag))
199 {
200 #if ENABLE_OBSOLETE_API_ENOSYS
201 /* Make sure sensitive data is erased in case
202 case get_random_bytes() fails. */
203 explicit_bzero(block, 64);
204
205 /* Overwrite sensitive data with random data. */
206 get_random_bytes(block, 64);
207
208 /* This function is not supported in this configuration. */
209 errno = ENOSYS;
210 #else
211 do_encrypt_r (block, edflag, &nr_encrypt_ctx);
212 #endif
213 }
214 SYMVER_encrypt;
215 #endif