1DES_CRYPT(3) BSD Library Functions Manual DES_CRYPT(3)
2
4 des_crypt, ecb_crypt, cbc_crypt, des_setparity — fast DES encryption
5
7 #include <rpc/des_crypt.h>
8 int
10 ecb_crypt(char *key, char *data, unsigned datalen, unsigned mode);
11 int
13 cbc_crypt(char *key, char *data, unsigned datalen, unsigned mode,
14 char *ivec);
15 void
17 des_setparity(char *key);
18
20 The ecb_crypt() and cbc_crypt() functions implement the NBS DES (Data
21 Encryption Standard). These routines are faster and more general purpose
22 than crypt(3). They also are able to utilize DES hardware if it is
23 available. The ecb_crypt() function encrypts in ECB (Electronic Code
24 Book) mode, which encrypts blocks of data independently. The cbc_crypt()
25 function encrypts in CBC (Cipher Block Chaining) mode, which chains
26 together successive blocks. CBC mode protects against insertions, dele‐
27 tions and substitutions of blocks. Also, regularities in the clear text
28 will not appear in the cipher text.
29 Here is how to use these routines. The first argument, key, is the
31 8-byte encryption key with parity. To set the key's parity, which for
32 DES is in the low bit of each byte, use des_setparity(). The second
33 argument, data, contains the data to be encrypted or decrypted. The
34 third argument, datalen, is the length in bytes of data, which must be a
35 multiple of 8. The fourth argument, mode, is formed by OR'ing together
36 some things. For the encryption direction OR in either DES_ENCRYPT or
37 DES_DECRYPT. For software versus hardware encryption, OR in either
38 DES_HW or DES_SW. If DES_HW is specified, and there is no hardware, then
39 the encryption is performed in software and the routine returns
40 DESERR_NOHWDEVICE. For cbc_crypt(), the ivec argument is the 8-byte ini‐
41 tialization vector for the chaining. It is updated to the next initial‐
42 ization vector upon return.
43
45 [DESERR_NONE] No error.
46 [DESERR_NOHWDEVICE] Encryption succeeded, but done in software instead
47 of the requested hardware.
48 [DESERR_HWERR] An error occurred in the hardware or driver.
49 [DESERR_BADPARAM] Bad argument to routine.
50 Given a result status stat, the macro DES_FAILED(stat) is false only for
52 the first two statuses.
53
55 The ecb_crypt(), cbc_crypt(), and des_setparity() functions are part of
56 libtirpc.
57
59 crypt(3)
60
62 These routines are not available in RPCSRC 4.0. This information is pro‐
63 vided to describe the DES interface expected by Secure RPC.
64BSD October 6, 1987 BSD