path: root/providers/implementations/rands/test_rng.c

/*
 * 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/core_numbers.h>
#include <openssl/e_os2.h>
#include <openssl/params.h>
#include "prov/providercommon.h"
#include "prov/provider_ctx.h"
#include "prov/provider_util.h"
#include "prov/implementations.h"
#include "drbg_local.h"

static OSSL_OP_rand_newctx_fn test_rng_new_wrapper;
static OSSL_OP_rand_freectx_fn test_rng_free;
static OSSL_OP_rand_instantiate_fn test_rng_instantiate_wrapper;
static OSSL_OP_rand_uninstantiate_fn test_rng_uninstantiate_wrapper;
static OSSL_OP_rand_generate_fn test_rng_generate_wrapper;
static OSSL_OP_rand_reseed_fn test_rng_reseed_wrapper;
static OSSL_OP_rand_nonce_fn test_rng_nonce;
static OSSL_OP_rand_settable_ctx_params_fn test_rng_settable_ctx_params;
static OSSL_OP_rand_set_ctx_params_fn test_rng_set_ctx_params;
static OSSL_OP_rand_gettable_ctx_params_fn test_rng_gettable_ctx_params;
static OSSL_OP_rand_get_ctx_params_fn test_rng_get_ctx_params;
static OSSL_OP_rand_verify_zeroization_fn test_rng_verify_zeroization;

typedef struct {
    unsigned char *entropy, *nonce;
    size_t entropy_len, entropy_pos, nonce_len;
    unsigned int strength;
} PROV_TEST_RNG;

static int test_rng_new(PROV_DRBG *ctx, int secure)
{
    PROV_TEST_RNG *t;

    t = OPENSSL_zalloc(sizeof(*t));
    if (t == NULL)
        return 0;
    ctx->data = t;
    ctx->seedlen = INT_MAX;
    ctx->max_entropylen = INT_MAX;
    ctx->max_noncelen = INT_MAX;
    ctx->max_perslen = INT_MAX;
    ctx->max_adinlen = INT_MAX;
    ctx->max_request = INT_MAX;
    ctx->strength = 1024;
    return 1;
}

static void *test_rng_new_wrapper(void *provctx, int secure, void *parent,
                                   const OSSL_DISPATCH *parent_dispatch)
{
    return prov_rand_drbg_new(provctx, secure, parent, parent_dispatch,
                              &test_rng_new);
}

static void test_rng_free(void *vdrbg)
{
    PROV_DRBG *drbg = (PROV_DRBG *)vdrbg;
    PROV_TEST_RNG *t = (PROV_TEST_RNG *)drbg->data;

    OPENSSL_free(t->entropy);
    OPENSSL_free(t->nonce);
    OPENSSL_free(drbg->data);
    prov_rand_drbg_free(drbg);
}

static int test_rng_instantiate(PROV_DRBG *drbg,
                                const unsigned char *ent, size_t ent_len,
                                const unsigned char *nonce, size_t nonce_len,
                                const unsigned char *pstr, size_t pstr_len)
{
    PROV_TEST_RNG *t = (PROV_TEST_RNG *)drbg->data;

    if (ent != NULL && (ent_len < drbg->min_entropylen
                        || ent_len >= drbg->max_entropylen))
        return 0;
    if (nonce != NULL && (nonce_len < drbg->min_noncelen
                        || nonce_len >= drbg->max_noncelen))
        return 0;
    if (pstr != NULL && pstr_len >= drbg->max_perslen)
        return 0;

    t->entropy_pos = 0;
    return 1;
}

static int test_rng_instantiate_wrapper(void *vdrbg, unsigned int strength,
                                        int prediction_resistance,
                                        const unsigned char *pstr,
                                        size_t pstr_len)
{
    PROV_DRBG *drbg = (PROV_DRBG *)vdrbg;

    if (pstr != NULL && pstr_len >= drbg->max_perslen)
        return 0;

    return PROV_DRBG_instantiate(drbg, strength, prediction_resistance,
                                 pstr, pstr_len);
}

static int test_rng_uninstantiate(PROV_DRBG *drbg)
{
    PROV_TEST_RNG *t = (PROV_TEST_RNG *)drbg->data;

    t->entropy_pos = 0;
    return 1;
}

static int test_rng_uninstantiate_wrapper(void *vdrbg)
{
    return test_rng_uninstantiate((PROV_DRBG *)vdrbg);
}

static int test_rng_generate(PROV_DRBG *drbg,
                             unsigned char *out, size_t outlen,
                             const unsigned char *adin, size_t adin_len)
{
    PROV_TEST_RNG *t = (PROV_TEST_RNG *)drbg->data;
    size_t i;

    if (t->entropy == NULL || (adin != NULL && adin_len >= drbg->max_adinlen))
        return 0;

    for (i = 0; i < outlen; i++) {
        out[i] = t->entropy[t->entropy_pos++];
        if (t->entropy_pos >= t->entropy_len)
            break;
    }
    return 1;
}

static int test_rng_generate_wrapper
    (void *vdrbg, unsigned char *out, size_t outlen,
      unsigned int strength, int prediction_resistance,
      const unsigned char *adin, size_t adin_len)
{
    PROV_DRBG *drbg = (PROV_DRBG *)vdrbg;

    if (strength > drbg->strength)
        return 0;
    return test_rng_generate(drbg, out, outlen, adin, adin_len);
}

static int test_rng_reseed(PROV_DRBG *drbg,
                            const unsigned char *ent, size_t ent_len,
                            const unsigned char *adin, size_t adin_len)
{
    if (ent != NULL && (ent_len < drbg->min_entropylen
                        || ent_len >= drbg->max_entropylen))
        return 0;
    if (adin != NULL && adin_len >= drbg->max_adinlen)
        return 0;

    return 1;
}

static int test_rng_reseed_wrapper(void *vdrbg, int prediction_resistance,
                                   const unsigned char *ent, size_t ent_len,
                                   const unsigned char *adin, size_t adin_len)
{
    return test_rng_reseed((PROV_DRBG *)vdrbg, ent, ent_len, adin, adin_len);
}

static void *test_rng_new_wrapper(void *provctx, void *parent,
                                   const OSSL_DISPATCH *parent_dispatch)
{
    return prov_rand_drbg_new(provctx, parent, parent_dispatch,
                              &test_rng_new, &test_rng_instantiate,
                              &test_rng_uninstantiate, &test_rng_reseed,
                              &test_rng_generate);
}

static size_t test_rng_nonce(void *vdrbg, unsigned char *out,
                             unsigned int strength, size_t min_noncelen,
                             size_t max_noncelen)
{
    PROV_DRBG *drbg = (PROV_DRBG *)vdrbg;
    PROV_TEST_RNG *t = (PROV_TEST_RNG *)drbg->data;

    if (t->nonce == NULL
            || strength > drbg->strength
            || min_noncelen > t->nonce_len
            || max_noncelen < t->nonce_len)
        return 0;

    if (out != NULL)
        memcpy(out, t->nonce, t->nonce_len);
    return t->nonce_len;
}

static int test_rng_get_ctx_params(void *vdrbg, OSSL_PARAM params[])
{
    PROV_DRBG *drbg = (PROV_DRBG *)vdrbg;

    return drbg_get_ctx_params(drbg, params);
}

static const OSSL_PARAM *test_rng_gettable_ctx_params(void)
{
    static const OSSL_PARAM known_gettable_ctx_params[] = {
        OSSL_PARAM_DRBG_GETABLE_CTX_COMMON,
        OSSL_PARAM_END
    };
    return known_gettable_ctx_params;
}

static int set_size_t(const OSSL_PARAM *params, const char *name,
                            size_t *val)
{
    const OSSL_PARAM *p = OSSL_PARAM_locate_const(params, name);

    return p == NULL || OSSL_PARAM_get_size_t(p, val);
}

static