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Diffstat (limited to 'doc/man/libkeccak_digest.3')
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diff --git a/doc/man/libkeccak_digest.3 b/doc/man/libkeccak_digest.3 new file mode 100644 index 0000000..a5cfb69 --- /dev/null +++ b/doc/man/libkeccak_digest.3 @@ -0,0 +1,78 @@ +.TH LIBKECCAK_DIGEST 3 LIBKECCAK-%VERSION% +.SH NAME +libkeccak_digest - Complete the hashing of a message with erasure +.SH SYNOPSIS +.LP +.nf +#include <libkeccak.h> +.P +int libkeccak_digest(libkeccak_state_t *\fIstate\fP, const char *\fImsg\fP, size_t \fImsglen\fP, + size_t \fIbits\fP, const char *\fIsuffix\fP, char *\fIhashsum\fP); +.fi +.P +Link with \fI-lkeccak\fP. +.SH DESCRIPTION +The +.BR libkeccak_digest () +function absorbs the last part of (or all of) a message, +and returns the hash of the entire message. The last part +of the message is specified by the \fImsg\fP parameter, and +its byte-size is specified by the \fImsglen\fP parameter. If +all of the message has already be processed by calls to the +.BR libkeccak_update (3) +function or the +.BR libkeccak_fast_update (3) +function (with the same pointer on \fIstate\fP,) \fImsg\fP +and \fImsglen\fP should be set to \fINULL\fP and 0, respectively. +.PP +If the message is not comprised a whole number of bytes, +the number of bits, modulus 8, in the message should be +specified in the \fIbits\fP parameter. \fImsglen\fP must only +count the number of whole bytes, that is, the floor of the +number of bits in the message divided by 8. +.PP +\fIsuffix\fP should be a NUL-terminated string of ASCII '1':s +and '0':s, representing the bits that should be appended to +the message. If this string is empty, \fINULL\fP may be used +instead. This is used to select hash algorithm. For pure Keccak, +\fINULL\fP or "" is used. For the other algorithms the constants +\fBLIBKECCAK_SHA3_SUFFIX\fP (for SHA-3), +\fBLIBKECCAK_RAWSHAKE_SUFFIX\fP (for RawSHAKE), and +\fBLIBKECCAK_SHAKE_SUFFIX\fP (for SHAKE) are used. +.PP +The hash of the message will be stored to \fIhashsum\fP, +unless \fIhashsum\fP is \fINULL\fP (which increases the +performance of the call.) A total of ((\fIstate->n\fP + 7) / 8) +bytes will be written to the beginning of \fIhashsum\fP. +Therefore, \fIhashsum\fP needs at least an allocation size +of that number of bytes. +.PP +The +.BR libkeccak_digest () +function may reallocate the state's message chunk buffer. +When doing so, it attempts to do so as securely as possible, +rather than as fast as possible. +.SH RETURN VALUES +The +.BR libkeccak_digest () +function returns 0 upon successful completion. On error, +-1 is returned and \fIerrno\fP is set to describe the error. +.SH ERRORS +The +.BR libkeccak_digest () +function may fail for any reason specified by the function +.BR malloc (3). +.SH SEE ALSO +.BR libkeccak_state_initialise (3), +.BR libkeccak_fast_update (3), +.BR libkeccak_update (3), +.BR libkeccak_fast_digest (3), +.BR libkeccak_simple_squeeze (3), +.BR libkeccak_fast_squeeze (3), +.BR libkeccak_squeeze (3) +.SH AUTHORS +Principal author, Mattias Andrée. See the LICENSE file for the full +list of authors. +.SH BUGS +Please report bugs to https://github.com/maandree/libkeccak/issues or to +maandree@member.fsf.org |