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DES_RANDOM_KEY(3ossl)                OpenSSL               DES_RANDOM_KEY(3ossl)





NAME

       DES_random_key, DES_set_key, DES_key_sched, DES_set_key_checked,
       DES_set_key_unchecked, DES_set_odd_parity, DES_is_weak_key,
       DES_ecb_encrypt, DES_ecb2_encrypt, DES_ecb3_encrypt, DES_ncbc_encrypt,
       DES_cfb_encrypt, DES_ofb_encrypt, DES_pcbc_encrypt, DES_cfb64_encrypt,
       DES_ofb64_encrypt, DES_xcbc_encrypt, DES_ede2_cbc_encrypt,
       DES_ede2_cfb64_encrypt, DES_ede2_ofb64_encrypt, DES_ede3_cbc_encrypt,
       DES_ede3_cfb64_encrypt, DES_ede3_ofb64_encrypt, DES_cbc_cksum,
       DES_quad_cksum, DES_string_to_key, DES_string_to_2keys, DES_fcrypt,
       DES_crypt - DES encryption


SYNOPSIS

        #include <openssl/des.h>

       The following functions have been deprecated since OpenSSL 3.0, and can
       be hidden entirely by defining OPENSSL_API_COMPAT with a suitable version
       value, see openssl_user_macros(7):

        void DES_random_key(DES_cblock *ret);

        int DES_set_key(const_DES_cblock *key, DES_key_schedule *schedule);
        int DES_key_sched(const_DES_cblock *key, DES_key_schedule *schedule);
        int DES_set_key_checked(const_DES_cblock *key, DES_key_schedule *schedule);
        void DES_set_key_unchecked(const_DES_cblock *key, DES_key_schedule *schedule);

        void DES_set_odd_parity(DES_cblock *key);
        int DES_is_weak_key(const_DES_cblock *key);

        void DES_ecb_encrypt(const_DES_cblock *input, DES_cblock *output,
                             DES_key_schedule *ks, int enc);
        void DES_ecb2_encrypt(const_DES_cblock *input, DES_cblock *output,
                              DES_key_schedule *ks1, DES_key_schedule *ks2, int enc);
        void DES_ecb3_encrypt(const_DES_cblock *input, DES_cblock *output,
                              DES_key_schedule *ks1, DES_key_schedule *ks2,
                              DES_key_schedule *ks3, int enc);

        void DES_ncbc_encrypt(const unsigned char *input, unsigned char *output,
                              long length, DES_key_schedule *schedule, DES_cblock *ivec,
                              int enc);
        void DES_cfb_encrypt(const unsigned char *in, unsigned char *out,
                             int numbits, long length, DES_key_schedule *schedule,
                             DES_cblock *ivec, int enc);
        void DES_ofb_encrypt(const unsigned char *in, unsigned char *out,
                             int numbits, long length, DES_key_schedule *schedule,
                             DES_cblock *ivec);
        void DES_pcbc_encrypt(const unsigned char *input, unsigned char *output,
                              long length, DES_key_schedule *schedule, DES_cblock *ivec,
                              int enc);
        void DES_cfb64_encrypt(const unsigned char *in, unsigned char *out,
                               long length, DES_key_schedule *schedule, DES_cblock *ivec,
                               int *num, int enc);
        void DES_ofb64_encrypt(const unsigned char *in, unsigned char *out,
                               long length, DES_key_schedule *schedule, DES_cblock *ivec,
                               int *num);

        void DES_xcbc_encrypt(const unsigned char *input, unsigned char *output,
                              long length, DES_key_schedule *schedule, DES_cblock *ivec,
                              const_DES_cblock *inw, const_DES_cblock *outw, int enc);

        void DES_ede2_cbc_encrypt(const unsigned char *input, unsigned char *output,
                                  long length, DES_key_schedule *ks1,
                                  DES_key_schedule *ks2, DES_cblock *ivec, int enc);
        void DES_ede2_cfb64_encrypt(const unsigned char *in, unsigned char *out,
                                    long length, DES_key_schedule *ks1,
                                    DES_key_schedule *ks2, DES_cblock *ivec,
                                    int *num, int enc);
        void DES_ede2_ofb64_encrypt(const unsigned char *in, unsigned char *out,
                                    long length, DES_key_schedule *ks1,
                                    DES_key_schedule *ks2, DES_cblock *ivec, int *num);

        void DES_ede3_cbc_encrypt(const unsigned char *input, unsigned char *output,
                                  long length, DES_key_schedule *ks1,
                                  DES_key_schedule *ks2, DES_key_schedule *ks3,
                                  DES_cblock *ivec, int enc);
        void DES_ede3_cfb64_encrypt(const unsigned char *in, unsigned char *out,
                                    long length, DES_key_schedule *ks1,
                                    DES_key_schedule *ks2, DES_key_schedule *ks3,
                                    DES_cblock *ivec, int *num, int enc);
        void DES_ede3_ofb64_encrypt(const unsigned char *in, unsigned char *out,
                                    long length, DES_key_schedule *ks1,
                                    DES_key_schedule *ks2, DES_key_schedule *ks3,
                                    DES_cblock *ivec, int *num);

        DES_LONG DES_cbc_cksum(const unsigned char *input, DES_cblock *output,
                               long length, DES_key_schedule *schedule,
                               const_DES_cblock *ivec);
        DES_LONG DES_quad_cksum(const unsigned char *input, DES_cblock output[],
                                long length, int out_count, DES_cblock *seed);
        void DES_string_to_key(const char *str, DES_cblock *key);
        void DES_string_to_2keys(const char *str, DES_cblock *key1, DES_cblock *key2);

        char *DES_fcrypt(const char *buf, const char *salt, char *ret);
        char *DES_crypt(const char *buf, const char *salt);


DESCRIPTION

       All of the functions described on this page are deprecated. Applications
       should instead use EVP_EncryptInit_ex(3), EVP_EncryptUpdate(3) and
       EVP_EncryptFinal_ex(3) or the equivalently named decrypt functions.

       This library contains a fast implementation of the DES encryption
       algorithm.

       There are two phases to the use of DES encryption.  The first is the
       generation of a DES_key_schedule from a key, the second is the actual
       encryption.  A DES key is of type DES_cblock. This type consists of 8
       bytes with odd parity.  The least significant bit in each byte is the
       parity bit.  The key schedule is an expanded form of the key; it is used
       to speed the encryption process.

       DES_random_key(3) generates a random key.  The random generator must be
       seeded when calling this function.  If the automatic seeding or reseeding
       of the OpenSSL CSPRNG fails due to external circumstances (see RAND(7)),
       the operation will fail.  If the function fails, 0 is returned.

       Before a DES key can be used, it must be converted into the architecture
       dependent DES_key_schedule via the DES_set_key_checked() or
       DES_set_key_unchecked() function.

       DES_set_key_checked() will check that the key passed is of odd parity and
       is not a weak or semi-weak key.  If the parity is wrong, then -1 is
       returned.  If the key is a weak key, then -2 is returned.  If an error is
       returned, the key schedule is not generated.

       DES_set_key() works like DES_set_key_checked() and remains for backward
       compatibility.

       DES_set_odd_parity() sets the parity of the passed key to odd.

       DES_is_weak_key() returns 1 if the passed key is a weak key, 0 if it is
       ok.

       The following routines mostly operate on an input and output stream of
       DES_cblocks.

       DES_ecb_encrypt() is the basic DES encryption routine that encrypts or
       decrypts a single 8-byte DES_cblock in electronic code book (ECB) mode.
       It always transforms the input data, pointed to by input, into the output
       data, pointed to by the output argument.  If the encrypt argument is
       nonzero (DES_ENCRYPT), the input (cleartext) is encrypted in to the
       output (ciphertext) using the key_schedule specified by the schedule
       argument, previously set via DES_set_key. If encrypt is zero
       (DES_DECRYPT), the input (now ciphertext) is decrypted into the output
       (now cleartext).  Input and output may overlap.  DES_ecb_encrypt() does
       not return a value.

       DES_ecb3_encrypt() encrypts/decrypts the input block by using three-key
       Triple-DES encryption in ECB mode.  This involves encrypting the input
       with ks1, decrypting with the key schedule ks2, and then encrypting with
       ks3.  This routine greatly reduces the chances of brute force breaking of
       DES and has the advantage of if ks1, ks2 and ks3 are the same, it is
       equivalent to just encryption using ECB mode and ks1 as the key.

       The macro DES_ecb2_encrypt() is provided to perform two-key Triple-DES
       encryption by using ks1 for the final encryption.

       DES_ncbc_encrypt() encrypts/decrypts using the cipher-block-chaining
       (CBC) mode of DES.  If the encrypt argument is nonzero, the routine
       cipher-block-chain encrypts the cleartext data pointed to by the input
       argument into the ciphertext pointed to by the output argument, using the
       key schedule provided by the schedule argument, and initialization vector
       provided by the ivec argument.  If the length argument is not an integral
       multiple of eight bytes, the last block is copied to a temporary area and
       zero filled.  The output is always an integral multiple of eight bytes.

       DES_xcbc_encrypt() is RSA's DESX mode of DES.  It uses inw and outw to
       'whiten' the encryption.  inw and outw are secret (unlike the iv) and are
       as such, part of the key.  So the key is sort of 24 bytes.  This is much
       better than CBC DES.

       DES_ede3_cbc_encrypt() implements outer triple CBC DES encryption with
       three keys. This means that each DES operation inside the CBC mode is
       "C=E(ks3,D(ks2,E(ks1,M)))".  This mode is used by SSL.

       The DES_ede2_cbc_encrypt() macro implements two-key Triple-DES by reusing
       ks1 for the final encryption.  "C=E(ks1,D(ks2,E(ks1,M)))".  This form of
       Triple-DES is used by the RSAREF library.

       DES_pcbc_encrypt() encrypts/decrypts using the propagating cipher block
       chaining mode used by Kerberos v4. Its parameters are the same as
       DES_ncbc_encrypt().

       DES_cfb_encrypt() encrypts/decrypts using cipher feedback mode.  This
       method takes an array of characters as input and outputs an array of
       characters.  It does not require any padding to 8 character groups.
       Note: the ivec variable is changed and the new changed value needs to be
       passed to the next call to this function.  Since this function runs a
       complete DES ECB encryption per numbits, this function is only suggested
       for use when sending a small number of characters.

       DES_cfb64_encrypt() implements CFB mode of DES with 64-bit feedback.  Why
       is this useful you ask?  Because this routine will allow you to encrypt
       an arbitrary number of bytes, without 8 byte padding.  Each call to this
       routine will encrypt the input bytes to output and then update ivec and
       num.  num contains 'how far' we are though ivec.  If this does not make
       much sense, read more about CFB mode of DES.

       DES_ede3_cfb64_encrypt() and DES_ede2_cfb64_encrypt() is the same as
       DES_cfb64_encrypt() except that Triple-DES is used.

       DES_ofb_encrypt() encrypts using output feedback mode.  This method takes
       an array of characters as input and outputs an array of characters.  It
       does not require any padding to 8 character groups.  Note: the ivec
       variable is changed and the new changed value needs to be passed to the
       next call to this function.  Since this function runs a complete DES ECB
       encryption per numbits, this function is only suggested for use when
       sending a small number of characters.

       DES_ofb64_encrypt() is the same as DES_cfb64_encrypt() using Output Feed
       Back mode.

       DES_ede3_ofb64_encrypt() and DES_ede2_ofb64_encrypt() is the same as
       DES_ofb64_encrypt(), using Triple-DES.

       The following functions are included in the DES library for compatibility
       with the MIT Kerberos library.

       DES_cbc_cksum() produces an 8 byte checksum based on the input stream
       (via CBC encryption).  The last 4 bytes of the checksum are returned and
       the complete 8 bytes are placed in output. This function is used by
       Kerberos v4.  Other applications should use EVP_DigestInit(3) etc.
       instead.

       DES_quad_cksum() is a Kerberos v4 function.  It returns a 4 byte checksum
       from the input bytes.  The algorithm can be iterated over the input,
       depending on out_count, 1, 2, 3 or 4 times.  If output is non-NULL, the 8
       bytes generated by each pass are written into output.

       The following are DES-based transformations:

       DES_fcrypt() is a fast version of the Unix crypt(3) function.  This
       version takes only a small amount of space relative to other fast crypt()
       implementations.  This is different to the normal crypt() in that the
       third parameter is the buffer that the return value is written into.  It
       needs to be at least 14 bytes long.  This function is thread safe, unlike
       the normal crypt().

       DES_crypt() is a faster replacement for the normal system crypt().  This
       function calls DES_fcrypt() with a static array passed as the third
       parameter.  This mostly emulates the normal non-thread-safe semantics of
       crypt(3).  The salt must be two ASCII characters.

       The values returned by DES_fcrypt() and DES_crypt() are terminated by NUL
       character.

       DES_enc_write() writes len bytes to file descriptor fd from buffer buf.
       The data is encrypted via pcbc_encrypt (default) using sched for the key
       and iv as a starting vector.  The actual data send down fd consists of 4
       bytes (in network byte order) containing the length of the following
       encrypted data.  The encrypted data then follows, padded with random data
       out to a multiple of 8 bytes.


BUGS

       DES_cbc_encrypt() does not modify ivec; use DES_ncbc_encrypt() instead.

       DES_cfb_encrypt() and DES_ofb_encrypt() operates on input of 8 bits.
       What this means is that if you set numbits to 12, and length to 2, the
       first 12 bits will come from the 1st input byte and the low half of the
       second input byte.  The second 12 bits will have the low 8 bits taken
       from the 3rd input byte and the top 4 bits taken from the 4th input byte.
       The same holds for output.  This function has been implemented this way
       because most people will be using a multiple of 8 and because once you
       get into pulling bytes input bytes apart things get ugly!

       DES_string_to_key() is available for backward compatibility with the MIT
       library.  New applications should use a cryptographic hash function.  The
       same applies for DES_string_to_2key().


NOTES

       The des library was written to be source code compatible with the MIT
       Kerberos library.

       Applications should use the higher level functions EVP_EncryptInit(3)
       etc. instead of calling these functions directly.

       Single-key DES is insecure due to its short key size.  ECB mode is not
       suitable for most applications; see des_modes(7).


RETURN VALUES

       DES_set_key(), DES_key_sched(), and DES_set_key_checked() return 0 on
       success or negative values on error.

       DES_is_weak_key() returns 1 if the passed key is a weak key, 0 if it is
       ok.

       DES_cbc_cksum() and DES_quad_cksum() return 4-byte integer representing
       the last 4 bytes of the checksum of the input.

       DES_fcrypt() returns a pointer to the caller-provided buffer and
       DES_crypt() - to a static buffer on success; otherwise they return NULL.


SEE ALSO

       des_modes(7), EVP_EncryptInit(3)


HISTORY

       All of these functions were deprecated in OpenSSL 3.0.

       The requirement that the salt parameter to DES_crypt() and DES_fcrypt()
       be two ASCII characters was first enforced in OpenSSL 1.1.0.  Previous
       versions tried to use the letter uppercase A if both character were not
       present, and could crash when given non-ASCII on some platforms.


COPYRIGHT

       Copyright 2000-2021 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the Apache License 2.0 (the "License").  You may not use
       this file except in compliance with the License.  You can obtain a copy
       in the file LICENSE in the source distribution or at
       <https://www.openssl.org/source/license.html>.



3.0.8                              2023-02-07              DES_RANDOM_KEY(3ossl)

openssl 3.0.8 - Generated Thu Feb 9 12:45:17 CST 2023
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