.TH LIBHASHSUM_GET_ALGORITHM_FROM_STRING 3 libhashsum
.SH NAME
libhashsum_get_algorithm_from_string - identify named hash function

.SH SYNOPSIS
.nf
#include <libhashsum.h>

\fBenum libhashsum_algorithm\fP { /* see the section DESCRIPTION for a listing of values */ };

int \fBlibhashsum_get_algorithm_from_string\fP(enum libhashsum_algorithm \fIalgorithm_out\fP, const char *\fIalgorithm\fP);
.fi
.PP
Link with
.IR -lhashsum .

.SH DESCRIPTION
The
.B libhashsum_get_algorithm_from_string
functions parses the string
.I algorithm
to identify the hash function it specifies,
and stores one of the following values in
.I *algorithm_out
to indicate the specified hash function:
.TP
.B LIBHASHSUM_MD2
MD2

.I algorithm
is
.RB \(dq MD2 \(dq.
.TP
.B LIBHASHSUM_MD4
MD4

.I algorithm
is
.RB \(dq MD4 \(dq.
.TP
.B LIBHASHSUM_MD5
MD5

.I algorithm
is
.RB \(dq MD5 \(dq.
.TP
.B LIBHASHSUM_RIPEMD_128
RIPEMD-128

.I algorithm
is
.RB \(dq RIPEMD-128 \(dq
or
.RB \(dq RMD-128 \(dq.
.TP
.B LIBHASHSUM_RIPEMD_160
RIPEMD-160

.I algorithm
is
.RB \(dq RIPEMD-160 \(dq
or
.RB \(dq RMD-160 \(dq.
.TP
.B LIBHASHSUM_RIPEMD_256
RIPEMD-256

.I algorithm
is
.RB \(dq RIPEMD-256 \(dq
or
.RB \(dq RMD-256 \(dq.
.TP
.B LIBHASHSUM_RIPEMD_512
RIPEMD-512

.I algorithm
is
.RB \(dq RIPEMD-512 \(dq
or
.RB \(dq RMD-512 \(dq.
.TP
.B LIBHASHSUM_SHA0
SHA-0

.I algorithm
is
.RB \(dq SHA-0 \(dq.
.TP
.B LIBHASHSUM_SHA1
SHA-1

.I algorithm
is
.RB \(dq SHA-1 \(dq.
.TP
.B LIBHASHSUM_SHA_224
SHA-224 (32-bit SHA-2 with 224 bit output)

.I algorithm
is
.RB \(dq SHA-224 \(dq
or
.RB \(dq SHA-2-224 \(dq.
.TP
.B LIBHASHSUM_SHA_256
SHA-256 (32-bit SHA-2 with 356 bit output)

.I algorithm
is
.RB \(dq SHA-256 \(dq
or
.RB \(dq SHA-2-256 \(dq.
.TP
.B LIBHASHSUM_SHA_384
SHA-384 (64-bit SHA-2 with 384 bit output)

.I algorithm
is
.RB \(dq SHA-384 \(dq
or
.RB \(dq SHA-2-384 \(dq.
.TP
.B LIBHASHSUM_SHA_512
SHA-512 (64-bit SHA-2 with 512 bit output)

.I algorithm
is
.RB \(dq SHA-512 \(dq
or
.RB \(dq SHA-2-512 \(dq.
.TP
.B LIBHASHSUM_SHA_512_224
SHA-512/224 (64-bit SHA-2 with 224 bit output)

.I algorithm
is
.RB \(dq SHA-512/224 \(dq
or
.RB \(dq SHA-2-512/224 \(dq,
where the slash
.RB (' / ')
may be replaces with a dash
.RB (' - ')
or underscore
.RB (' _ ').
.TP
.B LIBHASHSUM_SHA_512_256
SHA-512/256 (64-bit SHA-2 with 256 bit output)

.I algorithm
is
.RB \(dq SHA-512/256 \(dq
or
.RB \(dq SHA-2-512/256 \(dq,
where the slash
.RB (' / ')
may be replaces with a dash
.RB (' - ')
or underscore
.RB (' _ ').
.TP
.B LIBHASHSUM_KECCAK
Keccak

.I algorithm
is
.RB \(dq Keccak \(dq.
.TP
.B LIBHASHSUM_KECCAK_224
Keccak-224 (Keccak[n=224])

.I algorithm
is
.RB \(dq Keccak-224 \(dq.
.TP
.B LIBHASHSUM_KECCAK_256
Keccak-256 (Keccak[n=256])

.I algorithm
is
.RB \(dq Keccak-256 \(dq.
.TP
.B LIBHASHSUM_KECCAK_384
Keccak-384 (Keccak[n=384])

.I algorithm
is
.RB \(dq Keccak-384 \(dq.
.TP
.B LIBHASHSUM_KECCAK_512
Keccak-512 (Keccak[n=512])

.I algorithm
is
.RB \(dq Keccak-512 \(dq.
.TP
.B LIBHASHSUM_SHA3_224
SHA-3-224 (SHA-3 with 224 bit output)

.I algorithm
is
.RB \(dq SHA-3-224 \(dq.
.TP
.B LIBHASHSUM_SHA3_256
SHA-3-256 (SHA-3 with 256 bit output)

.I algorithm
is
.RB \(dq SHA-3-256 \(dq.
.TP
.B LIBHASHSUM_SHA3_384
SHA-3-384 (SHA-3 with 384 bit output)

.I algorithm
is
.RB \(dq SHA-3-384 \(dq.
.TP
.B LIBHASHSUM_SHA3_512
SHA-3-512 (SHA-3 with 512 bit output)

.I algorithm
is
.RB \(dq SHA-3-512 \(dq.
.TP
.B LIBHASHSUM_SHAKE128
SHAKE128 (SHAKE with 256 bit capacity, and default output of 128 bits)

.I algorithm
is
.RB \(dq SHAKE-128 \(dq.
.TP
.B LIBHASHSUM_SHAKE256
SHAKE128 (SHAKE with 512 bit capacity, and default output of 256 bits)

.I algorithm
is
.RB \(dq SHAKE-256 \(dq.
.TP
.B LIBHASHSUM_SHAKE512
SHAKE128 (SHAKE with 1024 bit capacity, and default output of 512 bits)

.I algorithm
is
.RB \(dq SHAKE-512 \(dq.
.TP
.B LIBHASHSUM_RAWSHAKE128
RawSHAKE128 (RawSHAKE with 256 bit capacity, and default output of 128 bits)

.I algorithm
is
.RB \(dq RawSHAKE-128 \(dq.
.TP
.B LIBHASHSUM_RAWSHAKE256
RawSHAKE128 (RawSHAKE with 512 bit capacity, and default output of 256 bits)

.I algorithm
is
.RB \(dq RawSHAKE-256 \(dq.
.TP
.B LIBHASHSUM_RAWSHAKE512
RawSHAKE128 (RawSHAKE with 1024 bit capacity, and default output of 512 bits)

.I algorithm
is
.RB \(dq RawSHAKE-512 \(dq.
.TP
.B LIBHASHSUM_BLAKE224
BLAKE224 (BLAKEs (BLAKE) with 224 bit output)

.I algorithm
is
.RB \(dq BLAKE-224 \(dq
or
.RB \(dq B224 \(dq.
.TP
.B LIBHASHSUM_BLAKE256
BLAKE256 (BLAKEs (BLAKE) with 256 bit output)

.I algorithm
is
.RB \(dq BLAKE-256 \(dq
or
.RB \(dq B256 \(dq.
.TP
.B LIBHASHSUM_BLAKE384
BLAKE384 (BLAKEb (BLAKE) with 384 bit output)

.I algorithm
is
.RB \(dq BLAKE-384 \(dq
or
.RB \(dq B384 \(dq.
.TP
.B LIBHASHSUM_BLAKE512
BLAKE512 (BLAKEb (BLAKE) with 512 bit output)

.I algorithm
is
.RB \(dq BLAKE-512 \(dq
or
.RB \(dq B512 \(dq.
.PP
The function is case-insensitive, and tolerates
skipping dashes
.RB (' - ')
that are not immediately after a digit. Additionally,
it will ignore the substring
.RB \(dq sum \(dq
if it is added to the end of the function name.
.PP
The function
.I does not
validate the parameters for the hash function
that may be places inside square brackets at
the end of
.IR algorithm .
.PP
.I algorithm_out
and
.I algorithm
must not be
.IR NULL .

.SH RETURN VALUE
The
.B libhashsum_get_algorithm_from_string
returns 1 if the hash function was identified.
Otherwise the function returns 0.
If 1 is returned, the
.I *algoritm_out
is set, otherwise
.I *algoritm_out
is unmodified.

.SH ERRORS
The
.B libhashsum_get_algorithm_from_string
function cannot fail.

.SH HISTORY
libhashsum 1.0.

.SH SEE ALSO
.BR libhashsum (7),
.BR libhashsum_init_hasher_from_string (3)