.\" -*- mode: troff; coding: utf-8 -*-
.\" Automatically generated by Pod::Man v6.0.2 (Pod::Simple 3.47)
.\"
.\" Standard preamble:
.\" ========================================================================
.de Sp \" Vertical space (when we can't use .PP)
.if t .sp .5v
.if n .sp
..
.de Vb \" Begin verbatim text
.ft CW
.nf
.ne \\$1
..
.de Ve \" End verbatim text
.ft R
.fi
..
.\" \*(C` and \*(C' are quotes in nroff, nothing in troff, for use with C<>.
.ie n \{\
.    ds C` ""
.    ds C' ""
'br\}
.el\{\
.    ds C`
.    ds C'
'br\}
.\"
.\" Escape single quotes in literal strings from groff's Unicode transform.
.ie \n(.g .ds Aq \(aq
.el       .ds Aq '
.\"
.\" If the F register is >0, we'll generate index entries on stderr for
.\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index
.\" entries marked with X<> in POD.  Of course, you'll have to process the
.\" output yourself in some meaningful fashion.
.\"
.\" Avoid warning from groff about undefined register 'F'.
.de IX
..
.nr rF 0
.if \n(.g .if rF .nr rF 1
.if (\n(rF:(\n(.g==0)) \{\
.    if \nF \{\
.        de IX
.        tm Index:\\$1\t\\n%\t"\\$2"
..
.        if !\nF==2 \{\
.            nr % 0
.            nr F 2
.        \}
.    \}
.\}
.rr rF
.\"
.\" Required to disable full justification in groff 1.23.0.
.if n .ds AD l
.\" ========================================================================
.\"
.IX Title "EVP_RAND-TEST-RAND 7ossl"
.TH EVP_RAND-TEST-RAND 7ossl 2026-01-27 3.5.5 OpenSSL
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
.if n .ad l
.nh
.SH NAME
EVP_RAND\-TEST\-RAND \- The test EVP_RAND implementation
.SH DESCRIPTION
.IX Header "DESCRIPTION"
Support for a test generator through the \fBEVP_RAND\fR API. This generator is
for test purposes only, it does not generate random numbers.
.SS Identity
.IX Subsection "Identity"
"TEST\-RAND" is the name for this implementation; it can be used with the
\&\fBEVP_RAND_fetch()\fR function.
.SS "Supported parameters"
.IX Subsection "Supported parameters"
The supported parameters are:
.IP """state"" (\fBOSSL_RAND_PARAM_STATE\fR) <integer>" 4
.IX Item """state"" (OSSL_RAND_PARAM_STATE) <integer>"
.PD 0
.IP """fips\-indicator"" (\fBOSSL_RAND_PARAM_FIPS_APPROVED_INDICATOR\fR) <integer>" 4
.IX Item """fips-indicator"" (OSSL_RAND_PARAM_FIPS_APPROVED_INDICATOR) <integer>"
.PD
These parameter works as described in "PARAMETERS" in \fBEVP_RAND\fR\|(3).
.IP """strength"" (\fBOSSL_RAND_PARAM_STRENGTH\fR) <unsigned integer>" 4
.IX Item """strength"" (OSSL_RAND_PARAM_STRENGTH) <unsigned integer>"
.PD 0
.IP """reseed_requests"" (\fBOSSL_DRBG_PARAM_RESEED_REQUESTS\fR) <unsigned integer>" 4
.IX Item """reseed_requests"" (OSSL_DRBG_PARAM_RESEED_REQUESTS) <unsigned integer>"
.IP """reseed_time_interval"" (\fBOSSL_DRBG_PARAM_RESEED_TIME_INTERVAL\fR) <integer>" 4
.IX Item """reseed_time_interval"" (OSSL_DRBG_PARAM_RESEED_TIME_INTERVAL) <integer>"
.IP """max_request"" (\fBOSSL_DRBG_PARAM_RESEED_REQUESTS\fR) <unsigned integer>" 4
.IX Item """max_request"" (OSSL_DRBG_PARAM_RESEED_REQUESTS) <unsigned integer>"
.IP """min_entropylen"" (\fBOSSL_DRBG_PARAM_MIN_ENTROPYLEN\fR) <unsigned integer>" 4
.IX Item """min_entropylen"" (OSSL_DRBG_PARAM_MIN_ENTROPYLEN) <unsigned integer>"
.IP """max_entropylen"" (\fBOSSL_DRBG_PARAM_MAX_ENTROPYLEN\fR) <unsigned integer>" 4
.IX Item """max_entropylen"" (OSSL_DRBG_PARAM_MAX_ENTROPYLEN) <unsigned integer>"
.IP """min_noncelen"" (\fBOSSL_DRBG_PARAM_MIN_NONCELEN\fR) <unsigned integer>" 4
.IX Item """min_noncelen"" (OSSL_DRBG_PARAM_MIN_NONCELEN) <unsigned integer>"
.IP """max_noncelen"" (\fBOSSL_DRBG_PARAM_MAX_NONCELEN\fR) <unsigned integer>" 4
.IX Item """max_noncelen"" (OSSL_DRBG_PARAM_MAX_NONCELEN) <unsigned integer>"
.IP """max_perslen"" (\fBOSSL_DRBG_PARAM_MAX_PERSLEN\fR) <unsigned integer>" 4
.IX Item """max_perslen"" (OSSL_DRBG_PARAM_MAX_PERSLEN) <unsigned integer>"
.IP """max_adinlen"" (\fBOSSL_DRBG_PARAM_MAX_ADINLEN\fR) <unsigned integer>" 4
.IX Item """max_adinlen"" (OSSL_DRBG_PARAM_MAX_ADINLEN) <unsigned integer>"
.IP """reseed_counter"" (\fBOSSL_DRBG_PARAM_RESEED_COUNTER\fR) <unsigned integer>" 4
.IX Item """reseed_counter"" (OSSL_DRBG_PARAM_RESEED_COUNTER) <unsigned integer>"
.PD
These parameters work as described in "PARAMETERS" in \fBEVP_RAND\fR\|(3), except that
they can all be set as well as read.
.IP """test_entropy"" (\fBOSSL_RAND_PARAM_TEST_ENTROPY\fR) <octet string>" 4
.IX Item """test_entropy"" (OSSL_RAND_PARAM_TEST_ENTROPY) <octet string>"
Sets the bytes returned when the test generator is sent an entropy request.
The current position is remembered across generate calls.
If there are insufficient data present to satisfy a call, an error is returned.
.IP """test_nonce"" (\fBOSSL_RAND_PARAM_TEST_NONCE\fR) <octet string>" 4
.IX Item """test_nonce"" (OSSL_RAND_PARAM_TEST_NONCE) <octet string>"
Sets the bytes returned when the test generator is sent a nonce request.
Each nonce request will return all of the bytes.
.IP """generate"" (\fBOSSL_RAND_PARAM_GENERATE\fR) <integer>" 4
.IX Item """generate"" (OSSL_RAND_PARAM_GENERATE) <integer>"
If this parameter is zero, it will only emit the nonce and entropy data
supplied via the aforementioned parameters.  Otherwise, low quality
non\-cryptographic pseudorandom output is produced.  This parameter defaults
to zero.
.SH NOTES
.IX Header "NOTES"
A context for a test generator can be obtained by calling:
.PP
.Vb 2
\& EVP_RAND *rand = EVP_RAND_fetch(NULL, "TEST\-RAND", NULL);
\& EVP_RAND_CTX *rctx = EVP_RAND_CTX_new(rand, NULL);
.Ve
.SH EXAMPLES
.IX Header "EXAMPLES"
.Vb 7
\& EVP_RAND *rand;
\& EVP_RAND_CTX *rctx;
\& unsigned char bytes[100];
\& OSSL_PARAM params[4], *p = params;
\& unsigned char entropy[1000] = { ... };
\& unsigned char nonce[20] = { ... };
\& unsigned int strength = 48;
\&
\& rand = EVP_RAND_fetch(NULL, "TEST\-RAND", NULL);
\& rctx = EVP_RAND_CTX_new(rand, NULL);
\& EVP_RAND_free(rand);
\&
\& *p++ = OSSL_PARAM_construct_uint(OSSL_RAND_PARAM_STRENGTH, &strength);
\& *p++ = OSSL_PARAM_construct_octet_string(OSSL_RAND_PARAM_TEST_ENTROPY,
\&                                          entropy, sizeof(entropy));
\& *p++ = OSSL_PARAM_construct_octet_string(OSSL_RAND_PARAM_TEST_NONCE,
\&                                          nonce, sizeof(nonce));
\& *p = OSSL_PARAM_construct_end();
\& EVP_RAND_instantiate(rctx, strength, 0, NULL, 0, params);
\&
\& EVP_RAND_generate(rctx, bytes, sizeof(bytes), strength, 0, NULL, 0);
\&
\& EVP_RAND_CTX_free(rctx);
.Ve
.SH "SEE ALSO"
.IX Header "SEE ALSO"
\&\fBEVP_RAND\fR\|(3),
"PARAMETERS" in \fBEVP_RAND\fR\|(3)
.SH HISTORY
.IX Header "HISTORY"
This functionality was added in OpenSSL 3.0.
.SH COPYRIGHT
.IX Header "COPYRIGHT"
Copyright 2020\-2024 The OpenSSL Project Authors. All Rights Reserved.
.PP
Licensed under the Apache License 2.0 (the "License").  You may not use
this file except in compliance with the License.  You can obtain a copy
in the file LICENSE in the source distribution or at
<https://www.openssl.org/source/license.html>.
