RIPEMD(3) BSD Library Functions Manual RIPEMD(3)NAME
RIPEMD160_Init, RIPEMD160_Update, RIPEMD160_Final, RIPEMD160_End,
RIPEMD160_File, RIPEMD160_FileChunk, RIPEMD160_Data — calculate the
RIPEMD160 message digest
RIPEMD160_Update(RIPEMD160_CTX *context, const unsigned char *data,
unsigned int len);
RIPEMD160_Final(unsigned char digest, RIPEMD160_CTX *context);
RIPEMD160_End(RIPEMD160_CTX *context, char *buf);
RIPEMD160_File(const char *filename, char *buf);
RIPEMD160_FileChunk(const char *filename, char *buf, off_t offset,
RIPEMD160_Data(const unsigned char *data, unsigned int len, char *buf);
The RIPEMD160_ functions calculate a 160-bit cryptographic checksum
(digest) for any number of input bytes. A cryptographic checksum is a
one-way hash function; that is, it is computationally impractical to find
the input corresponding to a particular output. This net result is a
“fingerprint” of the input-data, which does not disclose the actual
The RIPEMD160_Init(), RIPEMD160_Update(), and RIPEMD160_Final() functions
are the core functions. Allocate an RIPEMD160_CTX, initialize it with
RIPEMD160_Init(), run over the data with RIPEMD160_Update(), and finally
extract the result using RIPEMD160_Final().
The RIPEMD160_End() function is a wrapper for RIPEMD160_Final() which
converts the return value to a 41-character (including the terminating
'\0') ASCII string which represents the 160 bits in hexadecimal.
The RIPEMD160_File() function calculates the digest of a file, and uses
RIPEMD160_End() to return the result. If the file cannot be opened, a
null pointer is returned. The RIPEMD160_FileChunk() function is similar
to RIPEMD160_File(), but it only calculates the digest over a byte-range
of the file specified, starting at offset and spanning length bytes. If
the length parameter is specified as 0, or more than the length of the
remaining part of the file, RIPEMD160_FileChunk() calculates the digest
from offset to the end of file. The RIPEMD160_Data() function calculates
the digest of a chunk of data in memory, and uses RIPEMD160_End() to
return the result.
When using RIPEMD160_End(), RIPEMD160_File(), or RIPEMD160_Data(), the
buf argument can be a null pointer, in which case the returned string is
allocated with malloc(3) and subsequently must be explicitly deallocated
using free(3) after use. If the buf argument is non-null it must point
to at least 41 characters of buffer space.
SEE ALSOmd2(3), md4(3), md5(3), sha(3)HISTORY
These functions appeared in FreeBSD 4.0.
The core hash routines were implemented by Eric Young based on the pub‐
lished RIPEMD160 specification.
No method is known to exist which finds two files having the same hash
value, nor to find a file with a specific hash value. There is on the
other hand no guarantee that such a method does not exist.
BSD February 26, 1999 BSD