| mdX.3 (0552350ecc55f34e3385dc06abf3c9c45092b332) | mdX.3 (dc2af37d961f722d07a89e658782e15a977e5549) |
|---|---|
| 1.\" 2.\" ---------------------------------------------------------------------------- 3.\" "THE BEER-WARE LICENSE" (Revision 42): 4.\" <phk@FreeBSD.org> wrote this file. As long as you retain this notice you 5.\" can do whatever you want with this stuff. If we meet some day, and you think 6.\" this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp 7.\" ---------------------------------------------------------------------------- 8.\" --- 30 unchanged lines hidden (view full) --- 39.Ft "char *" 40.Fn MDXFile "const char *filename" "char *buf" 41.Ft "char *" 42.Fn MDXFileChunk "const char *filename" "char *buf" "off_t offset" "off_t length" 43.Ft "char *" 44.Fn MDXData "const unsigned char *data" "unsigned int len" "char *buf" 45.Sh DESCRIPTION 46The MDX functions calculate a 128-bit cryptographic checksum (digest) | 1.\" 2.\" ---------------------------------------------------------------------------- 3.\" "THE BEER-WARE LICENSE" (Revision 42): 4.\" <phk@FreeBSD.org> wrote this file. As long as you retain this notice you 5.\" can do whatever you want with this stuff. If we meet some day, and you think 6.\" this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp 7.\" ---------------------------------------------------------------------------- 8.\" --- 30 unchanged lines hidden (view full) --- 39.Ft "char *" 40.Fn MDXFile "const char *filename" "char *buf" 41.Ft "char *" 42.Fn MDXFileChunk "const char *filename" "char *buf" "off_t offset" "off_t length" 43.Ft "char *" 44.Fn MDXData "const unsigned char *data" "unsigned int len" "char *buf" 45.Sh DESCRIPTION 46The MDX functions calculate a 128-bit cryptographic checksum (digest) |
| 47for any number of input bytes. A cryptographic checksum is a one-way | 47for any number of input bytes. 48A cryptographic checksum is a one-way |
| 48hash-function, that is, you cannot find (except by exhaustive search) | 49hash-function, that is, you cannot find (except by exhaustive search) |
| 49the input corresponding to a particular output. This net result is 50a ``fingerprint'' of the input-data, which doesn't disclose the actual 51input. | 50the input corresponding to a particular output. 51This net result is a 52.Dq fingerprint 53of the input-data, which doesn't disclose the actual input. |
| 52.Pp 53MD2 is the slowest, MD4 is the fastest and MD5 is somewhere in the middle. 54MD2 can only be used for Privacy-Enhanced Mail. 55MD4 has now been broken; it should only be used where necessary for 56backward compatibility. 57MD5 has not yet (1999-02-11) been broken, but sufficient attacks have been | 54.Pp 55MD2 is the slowest, MD4 is the fastest and MD5 is somewhere in the middle. 56MD2 can only be used for Privacy-Enhanced Mail. 57MD4 has now been broken; it should only be used where necessary for 58backward compatibility. 59MD5 has not yet (1999-02-11) been broken, but sufficient attacks have been |
| 58made that its security is in some doubt. The attacks on both MD4 and MD5 59are both in the nature of finding ``collisions'' \- that is, multiple | 60made that its security is in some doubt. 61The attacks on both MD4 and MD5 62are both in the nature of finding 63.Dq collisions 64\[en] 65that is, multiple |
| 60inputs which hash to the same value; it is still unlikely for an attacker 61to be able to determine the exact original input given a hash value. 62.Pp 63The 64.Fn MDXInit , 65.Fn MDXUpdate , 66and 67.Fn MDXFinal | 66inputs which hash to the same value; it is still unlikely for an attacker 67to be able to determine the exact original input given a hash value. 68.Pp 69The 70.Fn MDXInit , 71.Fn MDXUpdate , 72and 73.Fn MDXFinal |
| 68functions are the core functions. Allocate an MDX_CTX, initialize it with | 74functions are the core functions. 75Allocate an 76.Vt MDX_CTX , 77initialize it with |
| 69.Fn MDXInit , 70run over the data with 71.Fn MDXUpdate , 72and finally extract the result using 73.Fn MDXFinal . 74.Pp 75The 76.Fn MDXPad --- 117 unchanged lines hidden --- | 78.Fn MDXInit , 79run over the data with 80.Fn MDXUpdate , 81and finally extract the result using 82.Fn MDXFinal . 83.Pp 84The 85.Fn MDXPad --- 117 unchanged lines hidden --- |