5 DES_random_key, DES_set_key, DES_key_sched, DES_set_key_checked,
6 DES_set_key_unchecked, DES_set_odd_parity, DES_is_weak_key,
7 DES_ecb_encrypt, DES_ecb2_encrypt, DES_ecb3_encrypt, DES_ncbc_encrypt,
8 DES_cfb_encrypt, DES_ofb_encrypt, DES_pcbc_encrypt, DES_cfb64_encrypt,
9 DES_ofb64_encrypt, DES_xcbc_encrypt, DES_ede2_cbc_encrypt,
10 DES_ede2_cfb64_encrypt, DES_ede2_ofb64_encrypt, DES_ede3_cbc_encrypt,
11 DES_ede3_cfb64_encrypt, DES_ede3_ofb64_encrypt,
12 DES_cbc_cksum, DES_quad_cksum, DES_string_to_key, DES_string_to_2keys,
13 DES_fcrypt, DES_crypt - DES encryption
17 #include <openssl/des.h>
19 Deprecated since OpenSSL 3.0, can be hidden entirely by defining
20 B<OPENSSL_API_COMPAT> with a suitable version value, see
21 L<openssl_user_macros(7)>:
23 void DES_random_key(DES_cblock *ret);
25 int DES_set_key(const_DES_cblock *key, DES_key_schedule *schedule);
26 int DES_key_sched(const_DES_cblock *key, DES_key_schedule *schedule);
27 int DES_set_key_checked(const_DES_cblock *key, DES_key_schedule *schedule);
28 void DES_set_key_unchecked(const_DES_cblock *key, DES_key_schedule *schedule);
30 void DES_set_odd_parity(DES_cblock *key);
31 int DES_is_weak_key(const_DES_cblock *key);
33 void DES_ecb_encrypt(const_DES_cblock *input, DES_cblock *output,
34 DES_key_schedule *ks, int enc);
35 void DES_ecb2_encrypt(const_DES_cblock *input, DES_cblock *output,
36 DES_key_schedule *ks1, DES_key_schedule *ks2, int enc);
37 void DES_ecb3_encrypt(const_DES_cblock *input, DES_cblock *output,
38 DES_key_schedule *ks1, DES_key_schedule *ks2,
39 DES_key_schedule *ks3, int enc);
41 void DES_ncbc_encrypt(const unsigned char *input, unsigned char *output,
42 long length, DES_key_schedule *schedule, DES_cblock *ivec,
44 void DES_cfb_encrypt(const unsigned char *in, unsigned char *out,
45 int numbits, long length, DES_key_schedule *schedule,
46 DES_cblock *ivec, int enc);
47 void DES_ofb_encrypt(const unsigned char *in, unsigned char *out,
48 int numbits, long length, DES_key_schedule *schedule,
50 void DES_pcbc_encrypt(const unsigned char *input, unsigned char *output,
51 long length, DES_key_schedule *schedule, DES_cblock *ivec,
53 void DES_cfb64_encrypt(const unsigned char *in, unsigned char *out,
54 long length, DES_key_schedule *schedule, DES_cblock *ivec,
56 void DES_ofb64_encrypt(const unsigned char *in, unsigned char *out,
57 long length, DES_key_schedule *schedule, DES_cblock *ivec,
60 void DES_xcbc_encrypt(const unsigned char *input, unsigned char *output,
61 long length, DES_key_schedule *schedule, DES_cblock *ivec,
62 const_DES_cblock *inw, const_DES_cblock *outw, int enc);
64 void DES_ede2_cbc_encrypt(const unsigned char *input, unsigned char *output,
65 long length, DES_key_schedule *ks1,
66 DES_key_schedule *ks2, DES_cblock *ivec, int enc);
67 void DES_ede2_cfb64_encrypt(const unsigned char *in, unsigned char *out,
68 long length, DES_key_schedule *ks1,
69 DES_key_schedule *ks2, DES_cblock *ivec,
71 void DES_ede2_ofb64_encrypt(const unsigned char *in, unsigned char *out,
72 long length, DES_key_schedule *ks1,
73 DES_key_schedule *ks2, DES_cblock *ivec, int *num);
75 void DES_ede3_cbc_encrypt(const unsigned char *input, unsigned char *output,
76 long length, DES_key_schedule *ks1,
77 DES_key_schedule *ks2, DES_key_schedule *ks3,
78 DES_cblock *ivec, int enc);
79 void DES_ede3_cfb64_encrypt(const unsigned char *in, unsigned char *out,
80 long length, DES_key_schedule *ks1,
81 DES_key_schedule *ks2, DES_key_schedule *ks3,
82 DES_cblock *ivec, int *num, int enc);
83 void DES_ede3_ofb64_encrypt(const unsigned char *in, unsigned char *out,
84 long length, DES_key_schedule *ks1,
85 DES_key_schedule *ks2, DES_key_schedule *ks3,
86 DES_cblock *ivec, int *num);
88 DES_LONG DES_cbc_cksum(const unsigned char *input, DES_cblock *output,
89 long length, DES_key_schedule *schedule,
90 const_DES_cblock *ivec);
91 DES_LONG DES_quad_cksum(const unsigned char *input, DES_cblock output[],
92 long length, int out_count, DES_cblock *seed);
93 void DES_string_to_key(const char *str, DES_cblock *key);
94 void DES_string_to_2keys(const char *str, DES_cblock *key1, DES_cblock *key2);
96 char *DES_fcrypt(const char *buf, const char *salt, char *ret);
97 char *DES_crypt(const char *buf, const char *salt);
101 All of the functions described on this page are deprecated. Applications should
102 instead use L<EVP_EncryptInit_ex(3)>, L<EVP_EncryptUpdate(3)> and
103 L<EVP_EncryptFinal_ex(3)> or the equivalently named decrypt functions.
105 This library contains a fast implementation of the DES encryption
108 There are two phases to the use of DES encryption. The first is the
109 generation of a I<DES_key_schedule> from a key, the second is the
110 actual encryption. A DES key is of type I<DES_cblock>. This type
111 consists of 8 bytes with odd parity. The least significant bit in
112 each byte is the parity bit. The key schedule is an expanded form of
113 the key; it is used to speed the encryption process.
115 DES_random_key() generates a random key. The random generator must be
116 seeded when calling this function.
117 If the automatic seeding or reseeding of the OpenSSL CSPRNG fails due to
118 external circumstances (see L<RAND(7)>), the operation will fail.
119 If the function fails, 0 is returned.
121 Before a DES key can be used, it must be converted into the
122 architecture dependent I<DES_key_schedule> via the
123 DES_set_key_checked() or DES_set_key_unchecked() function.
125 DES_set_key_checked() will check that the key passed is of odd parity
126 and is not a weak or semi-weak key. If the parity is wrong, then -1
127 is returned. If the key is a weak key, then -2 is returned. If an
128 error is returned, the key schedule is not generated.
130 DES_set_key() works like DES_set_key_checked() and remains for
131 backward compatibility.
133 DES_set_odd_parity() sets the parity of the passed I<key> to odd.
135 DES_is_weak_key() returns 1 if the passed key is a weak key, 0 if it
138 The following routines mostly operate on an input and output stream of
141 DES_ecb_encrypt() is the basic DES encryption routine that encrypts or
142 decrypts a single 8-byte I<DES_cblock> in I<electronic code book>
143 (ECB) mode. It always transforms the input data, pointed to by
144 I<input>, into the output data, pointed to by the I<output> argument.
145 If the I<encrypt> argument is nonzero (DES_ENCRYPT), the I<input>
146 (cleartext) is encrypted in to the I<output> (ciphertext) using the
147 key_schedule specified by the I<schedule> argument, previously set via
148 I<DES_set_key>. If I<encrypt> is zero (DES_DECRYPT), the I<input> (now
149 ciphertext) is decrypted into the I<output> (now cleartext). Input
150 and output may overlap. DES_ecb_encrypt() does not return a value.
152 DES_ecb3_encrypt() encrypts/decrypts the I<input> block by using
153 three-key Triple-DES encryption in ECB mode. This involves encrypting
154 the input with I<ks1>, decrypting with the key schedule I<ks2>, and
155 then encrypting with I<ks3>. This routine greatly reduces the chances
156 of brute force breaking of DES and has the advantage of if I<ks1>,
157 I<ks2> and I<ks3> are the same, it is equivalent to just encryption
158 using ECB mode and I<ks1> as the key.
160 The macro DES_ecb2_encrypt() is provided to perform two-key Triple-DES
161 encryption by using I<ks1> for the final encryption.
163 DES_ncbc_encrypt() encrypts/decrypts using the I<cipher-block-chaining>
164 (CBC) mode of DES. If the I<encrypt> argument is nonzero, the
165 routine cipher-block-chain encrypts the cleartext data pointed to by
166 the I<input> argument into the ciphertext pointed to by the I<output>
167 argument, using the key schedule provided by the I<schedule> argument,
168 and initialization vector provided by the I<ivec> argument. If the
169 I<length> argument is not an integral multiple of eight bytes, the
170 last block is copied to a temporary area and zero filled. The output
171 is always an integral multiple of eight bytes.
173 DES_xcbc_encrypt() is RSA's DESX mode of DES. It uses I<inw> and
174 I<outw> to 'whiten' the encryption. I<inw> and I<outw> are secret
175 (unlike the iv) and are as such, part of the key. So the key is sort
176 of 24 bytes. This is much better than CBC DES.
178 DES_ede3_cbc_encrypt() implements outer triple CBC DES encryption with
179 three keys. This means that each DES operation inside the CBC mode is
180 C<C=E(ks3,D(ks2,E(ks1,M)))>. This mode is used by SSL.
182 The DES_ede2_cbc_encrypt() macro implements two-key Triple-DES by
183 reusing I<ks1> for the final encryption. C<C=E(ks1,D(ks2,E(ks1,M)))>.
184 This form of Triple-DES is used by the RSAREF library.
186 DES_pcbc_encrypt() encrypts/decrypts using the propagating cipher block
187 chaining mode used by Kerberos v4. Its parameters are the same as
190 DES_cfb_encrypt() encrypts/decrypts using cipher feedback mode. This
191 method takes an array of characters as input and outputs an array of
192 characters. It does not require any padding to 8 character groups.
193 Note: the I<ivec> variable is changed and the new changed value needs to
194 be passed to the next call to this function. Since this function runs
195 a complete DES ECB encryption per I<numbits>, this function is only
196 suggested for use when sending a small number of characters.
199 implements CFB mode of DES with 64-bit feedback. Why is this
200 useful you ask? Because this routine will allow you to encrypt an
201 arbitrary number of bytes, without 8 byte padding. Each call to this
202 routine will encrypt the input bytes to output and then update ivec
203 and num. num contains 'how far' we are though ivec. If this does
204 not make much sense, read more about CFB mode of DES.
206 DES_ede3_cfb64_encrypt() and DES_ede2_cfb64_encrypt() is the same as
207 DES_cfb64_encrypt() except that Triple-DES is used.
209 DES_ofb_encrypt() encrypts using output feedback mode. This method
210 takes an array of characters as input and outputs an array of
211 characters. It does not require any padding to 8 character groups.
212 Note: the I<ivec> variable is changed and the new changed value needs to
213 be passed to the next call to this function. Since this function runs
214 a complete DES ECB encryption per I<numbits>, this function is only
215 suggested for use when sending a small number of characters.
217 DES_ofb64_encrypt() is the same as DES_cfb64_encrypt() using Output
220 DES_ede3_ofb64_encrypt() and DES_ede2_ofb64_encrypt() is the same as
221 DES_ofb64_encrypt(), using Triple-DES.
223 The following functions are included in the DES library for
224 compatibility with the MIT Kerberos library.
226 DES_cbc_cksum() produces an 8 byte checksum based on the input stream
227 (via CBC encryption). The last 4 bytes of the checksum are returned
228 and the complete 8 bytes are placed in I<output>. This function is
229 used by Kerberos v4. Other applications should use
230 L<EVP_DigestInit(3)> etc. instead.
232 DES_quad_cksum() is a Kerberos v4 function. It returns a 4 byte
233 checksum from the input bytes. The algorithm can be iterated over the
234 input, depending on I<out_count>, 1, 2, 3 or 4 times. If I<output> is
235 non-NULL, the 8 bytes generated by each pass are written into
238 The following are DES-based transformations:
240 DES_fcrypt() is a fast version of the Unix crypt(3) function. This
241 version takes only a small amount of space relative to other fast
242 crypt() implementations. This is different to the normal crypt() in
243 that the third parameter is the buffer that the return value is
244 written into. It needs to be at least 14 bytes long. This function
245 is thread safe, unlike the normal crypt().
247 DES_crypt() is a faster replacement for the normal system crypt().
248 This function calls DES_fcrypt() with a static array passed as the
249 third parameter. This mostly emulates the normal non-thread-safe semantics
251 The B<salt> must be two ASCII characters.
253 The values returned by DES_fcrypt() and DES_crypt() are terminated by NUL
256 DES_enc_write() writes I<len> bytes to file descriptor I<fd> from
257 buffer I<buf>. The data is encrypted via I<pcbc_encrypt> (default)
258 using I<sched> for the key and I<iv> as a starting vector. The actual
259 data send down I<fd> consists of 4 bytes (in network byte order)
260 containing the length of the following encrypted data. The encrypted
261 data then follows, padded with random data out to a multiple of 8
266 DES_cbc_encrypt() does not modify B<ivec>; use DES_ncbc_encrypt()
269 DES_cfb_encrypt() and DES_ofb_encrypt() operates on input of 8 bits.
270 What this means is that if you set numbits to 12, and length to 2, the
271 first 12 bits will come from the 1st input byte and the low half of
272 the second input byte. The second 12 bits will have the low 8 bits
273 taken from the 3rd input byte and the top 4 bits taken from the 4th
274 input byte. The same holds for output. This function has been
275 implemented this way because most people will be using a multiple of 8
276 and because once you get into pulling bytes input bytes apart things
279 DES_string_to_key() is available for backward compatibility with the
280 MIT library. New applications should use a cryptographic hash function.
281 The same applies for DES_string_to_2key().
285 The B<des> library was written to be source code compatible with
286 the MIT Kerberos library.
288 Applications should use the higher level functions
289 L<EVP_EncryptInit(3)> etc. instead of calling these
292 Single-key DES is insecure due to its short key size. ECB mode is
293 not suitable for most applications; see L<des_modes(7)>.
297 DES_set_key(), DES_key_sched(), DES_set_key_checked() and DES_is_weak_key()
298 return 0 on success or negative values on error.
300 DES_cbc_cksum() and DES_quad_cksum() return 4-byte integer representing the
301 last 4 bytes of the checksum of the input.
303 DES_fcrypt() returns a pointer to the caller-provided buffer and DES_crypt() -
304 to a static buffer on success; otherwise they return NULL.
309 L<EVP_EncryptInit(3)>
313 All of these functions were deprecated in OpenSSL 3.0.
315 The requirement that the B<salt> parameter to DES_crypt() and DES_fcrypt()
316 be two ASCII characters was first enforced in
317 OpenSSL 1.1.0. Previous versions tried to use the letter uppercase B<A>
318 if both character were not present, and could crash when given non-ASCII
323 Copyright 2000-2020 The OpenSSL Project Authors. All Rights Reserved.
325 Licensed under the Apache License 2.0 (the "License"). You may not use
326 this file except in compliance with the License. You can obtain a copy
327 in the file LICENSE in the source distribution or at
328 L<https://www.openssl.org/source/license.html>.