rand: add a provider side seed source.
This allows the operating system sources that OpenSSL supports to be used directly as RNGs. It also allows DRBG seeding to be explicitly specified rather than being left to a fall back case. Reviewed-by: Matt Caswell <matt@openssl.org> (Merged from https://github.com/openssl/openssl/pull/13455)master
Pauli
3 years ago
parent
d8975dec0c
commit
81aef6ba72
@ -0,0 +1,87 @@
|
||||
=pod
|
||||
|
||||
=head1 NAME
|
||||
|
||||
EVP_RAND-SEED-SRC - The randomness seed source EVP_RAND implementation
|
||||
|
||||
=head1 DESCRIPTION
|
||||
|
||||
Support for deterministic random number generator seeding through the
|
||||
B<EVP_RAND> API.
|
||||
|
||||
The seed sources used are specified at the time OpenSSL is configured for
|
||||
building using the B<--with-rand-seed=> option. By default, operating system
|
||||
randomness sources are used.
|
||||
|
||||
=head2 Identity
|
||||
|
||||
"SEED-SRC" is the name for this implementation; it can be used with the
|
||||
EVP_RAND_fetch() function.
|
||||
|
||||
=head2 Supported parameters
|
||||
|
||||
The supported parameters are:
|
||||
|
||||
=over 4
|
||||
|
||||
=item "state" (B<OSSL_RAND_PARAM_STATE>) <integer>
|
||||
|
||||
=item "strength" (B<OSSL_RAND_PARAM_STRENGTH>) <unsigned integer>
|
||||
|
||||
=item "max_request" (B<OSSL_RAND_PARAM_MAX_REQUEST>) <unsigned integer>
|
||||
|
||||
These parameters work as described in L<EVP_RAND(3)/PARAMETERS>.
|
||||
|
||||
=back
|
||||
|
||||
=head1 NOTES
|
||||
|
||||
A context for the seed source can be obtained by calling:
|
||||
|
||||
EVP_RAND *rand = EVP_RAND_fetch(NULL, "SEED-SRC", NULL);
|
||||
EVP_RAND_CTX *rctx = EVP_RAND_CTX_new(rand);
|
||||
|
||||
=head1 EXAMPLES
|
||||
|
||||
EVP_RAND *rand;
|
||||
EVP_RAND_CTX *seed, *rctx;
|
||||
unsigned char bytes[100];
|
||||
OSSL_PARAM params[2], *p = params;
|
||||
unsigned int strength = 128;
|
||||
|
||||
/* Create a seed source */
|
||||
rand = EVP_RAND_fetch(NULL, "SEED-SRC", NULL);
|
||||
seed = EVP_RAND_CTX_new(rand, NULL);
|
||||
EVP_RAND_free(rand);
|
||||
|
||||
/* Feed this into a DRBG */
|
||||
rand = EVP_RAND_fetch(NULL, "CTR-DRBG", NULL);
|
||||
rctx = EVP_RAND_CTX_new(rand, seed);
|
||||
EVP_RAND_free(rand);
|
||||
|
||||
/* Configure the DRBG */
|
||||
*p++ = OSSL_PARAM_construct_utf8_string(OSSL_DRBG_PARAM_CIPHER,
|
||||
SN_aes_256_ctr, 0);
|
||||
*p = OSSL_PARAM_construct_end();
|
||||
EVP_RAND_set_ctx_params(rctx, params);
|
||||
|
||||
EVP_RAND_generate(rctx, bytes, sizeof(bytes), strength, 0, NULL, 0);
|
||||
|
||||
EVP_RAND_CTX_free(rctx);
|
||||
EVP_RAND_CTX_free(seed);
|
||||
|
||||
=head1 SEE ALSO
|
||||
|
||||
L<EVP_RAND(3)>,
|
||||
L<EVP_RAND(3)/PARAMETERS>
|
||||
|
||||
=head1 COPYRIGHT
|
||||
|
||||
Copyright 2020 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
|
||||
L<https://www.openssl.org/source/license.html>.
|
||||
|
||||
=cut
|
||||
@ -0,0 +1,192 @@
|
||||
/*
|
||||
* Copyright 2020 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
|
||||
*/
|
||||
|
||||
#include <string.h>
|
||||
#include <openssl/rand.h>
|
||||
#include <openssl/core_dispatch.h>
|
||||
#include <openssl/e_os2.h>
|
||||
#include <openssl/params.h>
|
||||
#include <openssl/core_names.h>
|
||||
#include <openssl/evp.h>
|
||||
#include <openssl/err.h>
|
||||
#include <openssl/randerr.h>
|
||||
#include "prov/implementations.h"
|
||||
#include "prov/provider_ctx.h"
|
||||
#include "prov/providercommonerr.h"
|
||||
#include "crypto/rand.h"
|
||||
#include "crypto/rand_pool.h"
|
||||
|
||||
static OSSL_FUNC_rand_newctx_fn seed_src_new;
|
||||
static OSSL_FUNC_rand_freectx_fn seed_src_free;
|
||||
static OSSL_FUNC_rand_instantiate_fn seed_src_instantiate;
|
||||
static OSSL_FUNC_rand_uninstantiate_fn seed_src_uninstantiate;
|
||||
static OSSL_FUNC_rand_generate_fn seed_src_generate;
|
||||
static OSSL_FUNC_rand_reseed_fn seed_src_reseed;
|
||||
static OSSL_FUNC_rand_gettable_ctx_params_fn seed_src_gettable_ctx_params;
|
||||
static OSSL_FUNC_rand_get_ctx_params_fn seed_src_get_ctx_params;
|
||||
static OSSL_FUNC_rand_verify_zeroization_fn seed_src_verify_zeroization;
|
||||
static OSSL_FUNC_rand_enable_locking_fn seed_src_enable_locking;
|
||||
|
||||
typedef struct {
|
||||
void *provctx;
|
||||
int state;
|
||||
} PROV_SEED_SRC;
|
||||
|
||||
static void *seed_src_new(void *provctx, void *parent,
|
||||
const OSSL_DISPATCH *parent_dispatch)
|
||||
{
|
||||
PROV_SEED_SRC *s;
|
||||
|
||||
if (parent != NULL) {
|
||||
ERR_raise(ERR_LIB_PROV, PROV_R_SEED_SOURCES_MUST_NOT_HAVE_A_PARENT);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
s = OPENSSL_zalloc(sizeof(*s));
|
||||
if (s == NULL) {
|
||||
ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
s->provctx = provctx;
|
||||
s->state = EVP_RAND_STATE_UNINITIALISED;
|
||||
return s;
|
||||
}
|
||||
|
||||
static void seed_src_free(void *vseed)
|
||||
{
|
||||
OPENSSL_free(vseed);
|
||||
}
|
||||
|
||||
static int seed_src_instantiate(void *vseed, unsigned int strength,
|
||||
int prediction_resistance,
|
||||
const unsigned char *pstr, size_t pstr_len)
|
||||
{
|
||||
PROV_SEED_SRC *s = (PROV_SEED_SRC *)vseed;
|
||||
|
||||
s->state = EVP_RAND_STATE_READY;
|
||||
return 1;
|
||||
}
|
||||
|
||||
static int seed_src_uninstantiate(void *vseed)
|
||||
{
|
||||
PROV_SEED_SRC *s = (PROV_SEED_SRC *)vseed;
|
||||
|
||||
s->state = EVP_RAND_STATE_UNINITIALISED;
|
||||
return 1;
|
||||
}
|
||||
|
||||
static int seed_src_generate(void *vseed, unsigned char *out, size_t outlen,
|
||||
unsigned int strength,
|
||||
ossl_unused int prediction_resistance,
|
||||
ossl_unused const unsigned char *adin,
|
||||
ossl_unused size_t adin_len)
|
||||
{
|
||||
PROV_SEED_SRC *s = (PROV_SEED_SRC *)vseed;
|
||||
size_t entropy_available;
|
||||
RAND_POOL *pool;
|
||||
|
||||
if (s->state != EVP_RAND_STATE_READY) {
|
||||
ERR_raise(ERR_LIB_PROV,
|
||||
s->state == EVP_RAND_STATE_ERROR ? PROV_R_IN_ERROR_STATE
|
||||
: PROV_R_NOT_INSTANTIATED);
|
||||
return 0;
|
||||
}
|
||||
|
||||
pool = rand_pool_new(strength, 1, outlen, outlen);
|
||||
if (pool == NULL) {
|
||||
ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Get entropy by polling system entropy sources. */
|
||||
entropy_available = ossl_pool_acquire_entropy(pool);
|
||||
|
||||
if (entropy_available > 0)
|
||||
memcpy(out, rand_pool_detach(pool), rand_pool_length(pool));
|
||||
|
||||
rand_pool_free(pool);
|
||||
return entropy_available > 0;
|
||||
}
|
||||
|
||||
static int seed_src_reseed(void *vseed,
|
||||
ossl_unused int prediction_resistance,
|
||||
ossl_unused const unsigned char *ent,
|
||||
ossl_unused size_t ent_len,
|
||||
ossl_unused const unsigned char *adin,
|
||||
ossl_unused size_t adin_len)
|
||||
{
|
||||
PROV_SEED_SRC *s = (PROV_SEED_SRC *)vseed;
|
||||
|
||||
if (s->state != EVP_RAND_STATE_READY) {
|
||||
ERR_raise(ERR_LIB_PROV,
|
||||
s->state == EVP_RAND_STATE_ERROR ? PROV_R_IN_ERROR_STATE
|
||||
: PROV_R_NOT_INSTANTIATED);
|
||||
return 0;
|
||||
}
|
||||
return 1;
|
||||
}
|
||||
|
||||
static int seed_src_get_ctx_params(void *vseed, OSSL_PARAM params[])
|
||||
{
|
||||
PROV_SEED_SRC *s = (PROV_SEED_SRC *)vseed;
|
||||
OSSL_PARAM *p;
|
||||
|
||||
p = OSSL_PARAM_locate(params, OSSL_RAND_PARAM_STATE);
|
||||
if (p != NULL && !OSSL_PARAM_set_int(p, s->state))
|
||||
return 0;
|
||||
|
||||
p = OSSL_PARAM_locate(params, OSSL_RAND_PARAM_STRENGTH);
|
||||
if (p != NULL && !OSSL_PARAM_set_int(p, 1024))
|
||||
return 0;
|
||||
|
||||
p = OSSL_PARAM_locate(params, OSSL_RAND_PARAM_MAX_REQUEST);
|
||||
if (p != NULL && !OSSL_PARAM_set_size_t(p, 128))
|
||||
return 0;
|
||||
return 1;
|
||||
}
|
||||
|
||||
static const OSSL_PARAM *seed_src_gettable_ctx_params(ossl_unused void *provctx)
|
||||
{
|
||||
static const OSSL_PARAM known_gettable_ctx_params[] = {
|
||||
OSSL_PARAM_int(OSSL_RAND_PARAM_STATE, NULL),
|
||||
OSSL_PARAM_uint(OSSL_RAND_PARAM_STRENGTH, NULL),
|
||||
OSSL_PARAM_size_t(OSSL_RAND_PARAM_MAX_REQUEST, NULL),
|
||||
OSSL_PARAM_END
|
||||
};
|
||||
return known_gettable_ctx_params;
|
||||
}
|
||||
|
||||
static int seed_src_verify_zeroization(ossl_unused void *vseed)
|
||||
{
|
||||
return 1;
|
||||
}
|
||||
|
||||
static int seed_src_enable_locking(ossl_unused void *vseed)
|
||||
{
|
||||
return 1;
|
||||
}
|
||||
|
||||
const OSSL_DISPATCH ossl_seed_src_functions[] = {
|
||||
{ OSSL_FUNC_RAND_NEWCTX, (void(*)(void))seed_src_new },
|
||||
{ OSSL_FUNC_RAND_FREECTX, (void(*)(void))seed_src_free },
|
||||
{ OSSL_FUNC_RAND_INSTANTIATE,
|
||||
(void(*)(void))seed_src_instantiate },
|
||||
{ OSSL_FUNC_RAND_UNINSTANTIATE,
|
||||
(void(*)(void))seed_src_uninstantiate },
|
||||
{ OSSL_FUNC_RAND_GENERATE, (void(*)(void))seed_src_generate },
|
||||
{ OSSL_FUNC_RAND_RESEED, (void(*)(void))seed_src_reseed },
|
||||
{ OSSL_FUNC_RAND_ENABLE_LOCKING, (void(*)(void))seed_src_enable_locking },
|
||||
{ OSSL_FUNC_RAND_GETTABLE_CTX_PARAMS,
|
||||
(void(*)(void))seed_src_gettable_ctx_params },
|
||||
{ OSSL_FUNC_RAND_GET_CTX_PARAMS, (void(*)(void))seed_src_get_ctx_params },
|
||||
{ OSSL_FUNC_RAND_VERIFY_ZEROIZATION,
|
||||
(void(*)(void))seed_src_verify_zeroization },
|
||||
{ 0, NULL }
|
||||
};
|
||||
Loading…
Reference in New Issue