test: add a test RNG.

The test RNG can provide pre-canned entropy and nonces for testing other
algorithms.

Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/11682)

providers/implementations/rands/test_rng.c

@@ -0,0 +1,332 @@
+/*
+ * 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 int test_rng_set_ctx_params(void *vdrbg, const OSSL_PARAM params[])
+{
+    PROV_DRBG *drbg = (PROV_DRBG *)vdrbg;
+    PROV_TEST_RNG *t = (PROV_TEST_RNG *)drbg->data;
+    const OSSL_PARAM *p;
+    void *ptr = NULL;
+    size_t size = 0;
+    unsigned int uint;
+
+    p = OSSL_PARAM_locate_const(params, OSSL_RAND_PARAM_STRENGTH);
+    if (p != NULL && !OSSL_PARAM_get_uint(p, &drbg->strength))
+        return 0;
+
+    p = OSSL_PARAM_locate_const(params, OSSL_RAND_PARAM_TEST_ENTROPY);
+    if (p != NULL) {
+        if (!OSSL_PARAM_get_octet_string(p, &ptr, 0, &size))
+            return 0;
+        OPENSSL_free(t->entropy);
+        t->entropy = ptr;
+        t->entropy_len = size;
+        t->entropy_pos = 0;
+        ptr = NULL;
+    }
+
+    p = OSSL_PARAM_locate_const(params, OSSL_RAND_PARAM_TEST_NONCE);
+    if (p != NULL) {
+        if (!OSSL_PARAM_get_octet_string(p, &ptr, 0, &size))
+            return 0;
+        OPENSSL_free(t->nonce);
+        t->nonce = ptr;
+        t->nonce_len = size;
+    }
+
+    p = OSSL_PARAM_locate_const(params, OSSL_DRBG_PARAM_RESEED_CTR);
+    if (p != NULL) {
+        if (!OSSL_PARAM_get_uint(p, &uint))
+            return 0;
+        tsan_store(&drbg->reseed_counter, uint);
+    }
+
+    p = OSSL_PARAM_locate_const(params, OSSL_DRBG_PARAM_RESEED_TIME);
+    if (p != NULL && !OSSL_PARAM_get_time_t(p, &drbg->reseed_time))
+        return 0;
+
+    if (!set_size_t(params, OSSL_DRBG_PARAM_MAX_REQUEST, &drbg->max_request)
+            || !set_size_t(params, OSSL_DRBG_PARAM_MIN_ENTROPYLEN,
+                           &drbg->min_entropylen)
+            || !set_size_t(params, OSSL_DRBG_PARAM_MAX_ENTROPYLEN,
+                           &drbg->max_entropylen)
+            || !set_size_t(params, OSSL_DRBG_PARAM_MIN_NONCELEN,
+                           &drbg->min_noncelen)
+            || !set_size_t(params, OSSL_DRBG_PARAM_MAX_NONCELEN,
+                           &drbg->max_noncelen)
+            || !set_size_t(params, OSSL_DRBG_PARAM_MAX_PERSLEN,
+                           &drbg->max_perslen)
+            || !set_size_t(params, OSSL_DRBG_PARAM_MAX_ADINLEN,
+                           &drbg->max_adinlen))
+        return 0;
+    return drbg_set_ctx_params(drbg, params);
+}
+
+static const OSSL_PARAM *test_rng_settable_ctx_params(void)
+{
+    static const OSSL_PARAM known_settable_ctx_params[] = {
+        OSSL_PARAM_octet_string(OSSL_RAND_PARAM_TEST_ENTROPY, NULL, 0),
+        OSSL_PARAM_octet_string(OSSL_RAND_PARAM_TEST_NONCE, NULL, 0),
+        OSSL_PARAM_uint(OSSL_RAND_PARAM_STRENGTH, NULL),
+        OSSL_PARAM_size_t(OSSL_DRBG_PARAM_MAX_REQUEST, NULL),
+        OSSL_PARAM_size_t(OSSL_DRBG_PARAM_MIN_ENTROPYLEN, NULL),
+        OSSL_PARAM_size_t(OSSL_DRBG_PARAM_MAX_ENTROPYLEN, NULL),
+        OSSL_PARAM_size_t(OSSL_DRBG_PARAM_MIN_NONCELEN, NULL),
+        OSSL_PARAM_size_t(OSSL_DRBG_PARAM_MAX_NONCELEN, NULL),
+        OSSL_PARAM_size_t(OSSL_DRBG_PARAM_MAX_PERSLEN, NULL),
+        OSSL_PARAM_size_t(OSSL_DRBG_PARAM_MAX_ADINLEN, NULL),
+        OSSL_PARAM_uint(OSSL_DRBG_PARAM_RESEED_CTR, NULL),
+        OSSL_PARAM_time_t(OSSL_DRBG_PARAM_RESEED_TIME, NULL),
+        OSSL_PARAM_DRBG_SETABLE_CTX_COMMON,
+        OSSL_PARAM_END
+    };
+    return known_settable_ctx_params;
+}
+
+static int test_rng_verify_zeroization(void *vdrbg)
+{
+    return 1;
+}
+
+const OSSL_DISPATCH test_rng_functions[] = {
+    { OSSL_FUNC_RAND_NEWCTX, (void(*)(void))test_rng_new_wrapper },
+    { OSSL_FUNC_RAND_FREECTX, (void(*)(void))test_rng_free },
+    { OSSL_FUNC_RAND_INSTANTIATE,
+      (void(*)(void))test_rng_instantiate_wrapper },
+    { OSSL_FUNC_RAND_UNINSTANTIATE,
+      (void(*)(void))test_rng_uninstantiate_wrapper },
+    { OSSL_FUNC_RAND_GENERATE, (void(*)(void))test_rng_generate_wrapper },
+    { OSSL_FUNC_RAND_RESEED, (void(*)(void))test_rng_reseed_wrapper },
+    { OSSL_FUNC_RAND_NONCE, (void(*)(void))test_rng_nonce },
+    { OSSL_FUNC_RAND_ENABLE_LOCKING, (void(*)(void))drbg_enable_locking },
+    { OSSL_FUNC_RAND_LOCK, (void(*)(void))drbg_lock },
+    { OSSL_FUNC_RAND_UNLOCK, (void(*)(void))drbg_unlock },
+    { OSSL_FUNC_RAND_SETTABLE_CTX_PARAMS,
+      (void(*)(void))test_rng_settable_ctx_params },
+    { OSSL_FUNC_RAND_SET_CTX_PARAMS, (void(*)(void))test_rng_set_ctx_params },
+    { OSSL_FUNC_RAND_GETTABLE_CTX_PARAMS,
+      (void(*)(void))test_rng_gettable_ctx_params },
+    { OSSL_FUNC_RAND_GET_CTX_PARAMS, (void(*)(void))test_rng_get_ctx_params },
+    { OSSL_FUNC_RAND_VERIFY_ZEROIZATION,
+      (void(*)(void))test_rng_verify_zeroization },
+    { 0, NULL }
+};