1des_crypt(3) Library Functions Manual des_crypt(3)
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6 des_crypt, ecb_crypt, cbc_crypt, des_setparity, DES_FAILED - fast DES
7 encryption
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10 Standard C library (libc, -lc)
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13 #include <rpc/des_crypt.h>
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15 [[deprecated]] int ecb_crypt(char *key, char data[.datalen],
16 unsigned int datalen, unsigned int mode);
17 [[deprecated]] int cbc_crypt(char *key, char data[.datalen],
18 unsigned int datalen, unsigned int mode,
19 char *ivec);
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21 [[deprecated]] void des_setparity(char *key);
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23 [[deprecated]] int DES_FAILED(int status);
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26 ecb_crypt() and cbc_crypt() implement the NBS DES (Data Encryption
27 Standard). These routines are faster and more general purpose than
28 crypt(3). They also are able to utilize DES hardware if it is avail‐
29 able. ecb_crypt() encrypts in ECB (Electronic Code Book) mode, which
30 encrypts blocks of data independently. cbc_crypt() encrypts in CBC
31 (Cipher Block Chaining) mode, which chains together successive blocks.
32 CBC mode protects against insertions, deletions, and substitutions of
33 blocks. Also, regularities in the clear text will not appear in the
34 cipher text.
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36 Here is how to use these routines. The first argument, key, is the
37 8-byte encryption key with parity. To set the key's parity, which for
38 DES is in the low bit of each byte, use des_setparity(). The second
39 argument, data, contains the data to be encrypted or decrypted. The
40 third argument, datalen, is the length in bytes of data, which must be
41 a multiple of 8. The fourth argument, mode, is formed by ORing to‐
42 gether some things. For the encryption direction OR in either DES_EN‐
43 CRYPT or DES_DECRYPT. For software versus hardware encryption, OR in
44 either DES_HW or DES_SW. If DES_HW is specified, and there is no hard‐
45 ware, then the encryption is performed in software and the routine re‐
46 turns DESERR_NOHWDEVICE. For cbc_crypt(), the argument ivec is the
47 8-byte initialization vector for the chaining. It is updated to the
48 next initialization vector upon return.
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51 DESERR_NONE
52 No error.
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54 DESERR_NOHWDEVICE
55 Encryption succeeded, but done in software instead of the re‐
56 quested hardware.
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58 DESERR_HWERROR
59 An error occurred in the hardware or driver.
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61 DESERR_BADPARAM
62 Bad argument to routine.
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64 Given a result status stat, the macro DES_FAILED(stat) is false only
65 for the first two statuses.
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68 For an explanation of the terms used in this section, see at‐
69 tributes(7).
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71 ┌────────────────────────────────────────────┬───────────────┬─────────┐
72 │Interface │ Attribute │ Value │
73 ├────────────────────────────────────────────┼───────────────┼─────────┤
74 │ecb_crypt(), cbc_crypt(), des_setparity() │ Thread safety │ MT-Safe │
75 └────────────────────────────────────────────┴───────────────┴─────────┘
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78 None.
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81 4.3BSD. glibc 2.1. Removed in glibc 2.28.
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83 Because they employ the DES block cipher, which is no longer considered
84 secure, these functions were removed. Applications should switch to a
85 modern cryptography library, such as libgcrypt.
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88 des(1), crypt(3), xcrypt(3)
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92Linux man-pages 6.04 2023-03-30 des_crypt(3)