des_crypt(3)		    Library Functions Manual		    des_crypt(3)

NAME
     des_crypt,	 ecb_crypt,  cbc_crypt, des_setparity, DES_FAILED - fast DES en-
     cryption

LIBRARY
     Standard C library (libc, -lc)

SYNOPSIS
     #include <rpc/des_crypt.h>

     [[deprecated]] int ecb_crypt(unsigned int datalen;
				  char *key, char data[datalen],
				  unsigned int datalen, unsigned int mode);
     [[deprecated]] int cbc_crypt(unsigned int datalen;
				  char *key, char data[datalen],
				  unsigned int datalen, unsigned int mode,
				  char *ivec);

     [[deprecated]] void des_setparity(char *key);

     [[deprecated]] int DES_FAILED(int status);

DESCRIPTION
     ecb_crypt() and cbc_crypt() implement the NBS DES	(Data  Encryption  Stan-
     dard).   These  routines are faster and more general purpose than crypt(3).
     They also are able to utilize DES hardware if it is available.  ecb_crypt()
     encrypts in ECB (Electronic Code Book) mode, which encrypts blocks of  data
     independently.   cbc_crypt()  encrypts in CBC (Cipher Block Chaining) mode,
     which chains together successive blocks.  CBC mode protects against  inser-
     tions,  deletions,	 and substitutions of blocks.  Also, regularities in the
     clear text will not appear in the cipher text.

     Here is how to use these routines.	 The first argument, key, is the  8-byte
     encryption	 key  with parity.  To set the key's parity, which for DES is in
     the low bit of each byte, use des_setparity().  The second argument,  data,
     contains  the  data  to  be  encrypted  or	 decrypted.  The third argument,
     datalen, is the length in bytes of data, which must be  a	multiple  of  8.
     The  fourth  argument,  mode, is formed by ORing together some things.  For
     the encryption direction OR in  either  DES_ENCRYPT  or  DES_DECRYPT.   For
     software  versus  hardware	 encryption,  OR in either DES_HW or DES_SW.  If
     DES_HW is specified, and there is no hardware, then the encryption is  per-
     formed   in  software  and	 the  routine  returns	DESERR_NOHWDEVICE.   For
     cbc_crypt(), the argument ivec is the 8-byte initialization vector for  the
     chaining.	It is updated to the next initialization vector upon return.

RETURN VALUE
     DESERR_NONE
	    No error.

     DESERR_NOHWDEVICE
	    Encryption	succeeded, but done in software instead of the requested
	    hardware.

     DESERR_HWERROR
	    An error occurred in the hardware or driver.

     DESERR_BADPARAM
	    Bad argument to routine.

     Given a result status stat, the macro DES_FAILED(stat) is	false  only  for
     the first two statuses.

ATTRIBUTES
     For  an  explanation  of the terms used in this section, see attributes(7).
     allbox; lbx lb lb l l l.  Interface Attribute Value T{ ecb_crypt(),
     cbc_crypt(), des_setparity() T}   Thread safety  MT-Safe

STANDARDS
     None.

HISTORY
     4.3BSD.  glibc 2.1.  Removed in glibc 2.28.

     Because they employ the DES block cipher, which is no longer considered se-
     cure, these functions were removed.  Applications should switch to a modern
     cryptography library, such as libgcrypt.

SEE ALSO
     des(1), crypt(3), xcrypt(3)

Linux man-pages 6.18		   2026-02-08			    des_crypt(3)