EVP_RAND-TEST-RAND(7ossl) OpenSSL EVP_RAND-TEST-RAND(7ossl)
NAME
EVP_RAND-TEST-RAND - The test EVP_RAND implementation
DESCRIPTION
Support for a test generator through the EVP_RAND API. This generator
is for test purposes only, it does not generate random numbers.
Identity
"TEST-RAND" is the name for this implementation; it can be used with
the EVP_RAND_fetch() function.
Supported parameters
The supported parameters are:
"state" (OSSL_RAND_PARAM_STATE) <integer>
These parameter works as described in "PARAMETERS" in EVP_RAND(3).
"strength" (OSSL_RAND_PARAM_STRENGTH) <unsigned integer>
"reseed_requests" (OSSL_DRBG_PARAM_RESEED_REQUESTS) <unsigned integer>
"reseed_time_interval" (OSSL_DRBG_PARAM_RESEED_TIME_INTERVAL) <integer>
"max_request" (OSSL_DRBG_PARAM_RESEED_REQUESTS) <unsigned integer>
"min_entropylen" (OSSL_DRBG_PARAM_MIN_ENTROPYLEN) <unsigned integer>
"max_entropylen" (OSSL_DRBG_PARAM_MAX_ENTROPYLEN) <unsigned integer>
"min_noncelen" (OSSL_DRBG_PARAM_MIN_NONCELEN) <unsigned integer>
"max_noncelen" (OSSL_DRBG_PARAM_MAX_NONCELEN) <unsigned integer>
"max_perslen" (OSSL_DRBG_PARAM_MAX_PERSLEN) <unsigned integer>
"max_adinlen" (OSSL_DRBG_PARAM_MAX_ADINLEN) <unsigned integer>
"reseed_counter" (OSSL_DRBG_PARAM_RESEED_COUNTER) <unsigned integer>
These parameters work as described in "PARAMETERS" in EVP_RAND(3),
except that they can all be set as well as read.
"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.
"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.
"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.
NOTES
A context for a test generator can be obtained by calling:
EVP_RAND *rand = EVP_RAND_fetch(NULL, "TEST-RAND", NULL);
EVP_RAND_CTX *rctx = EVP_RAND_CTX_new(rand, NULL);
EXAMPLES
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);
SEE ALSO
EVP_RAND(3), "PARAMETERS" in EVP_RAND(3)
HISTORY
This functionality was added in OpenSSL 3.0.
COPYRIGHT
Copyright 2020-2023 The OpenSSL Project Authors. All Rights Reserved.
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>.
3.3.2 2024-09-04 EVP_RAND-TEST-RAND(7ossl)
openssl 3.3.2 - Generated Tue Oct 1 14:47:34 CDT 2024