/*
- * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
*
- * Licensed under the OpenSSL license (the "License"). You may not use
+ * 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 <time.h>
#include "internal/cryptlib.h"
#include <openssl/opensslconf.h>
-#include "internal/rand.h"
-
+#include "crypto/rand.h"
#include <openssl/engine.h>
+#include "internal/thread_once.h"
+#include "rand_local.h"
+#include "e_os.h"
+
+#ifndef FIPS_MODULE
+# ifndef OPENSSL_NO_ENGINE
+/* non-NULL if default_RAND_meth is ENGINE-provided */
+static ENGINE *funct_ref;
+static CRYPTO_RWLOCK *rand_engine_lock;
+# endif
+static CRYPTO_RWLOCK *rand_meth_lock;
+static const RAND_METHOD *default_RAND_meth;
+static CRYPTO_ONCE rand_init = CRYPTO_ONCE_STATIC_INIT;
-#ifdef OPENSSL_FIPS
-# include <openssl/fips.h>
-# include <openssl/fips_rand.h>
+static int rand_inited = 0;
+#endif /* FIPS_MODULE */
+
+#ifdef OPENSSL_RAND_SEED_RDTSC
+/*
+ * IMPORTANT NOTE: It is not currently possible to use this code
+ * because we are not sure about the amount of randomness it provides.
+ * Some SP900 tests have been run, but there is internal skepticism.
+ * So for now this code is not used.
+ */
+# error "RDTSC enabled? Should not be possible!"
+
+/*
+ * Acquire entropy from high-speed clock
+ *
+ * Since we get some randomness from the low-order bits of the
+ * high-speed clock, it can help.
+ *
+ * Returns the total entropy count, if it exceeds the requested
+ * entropy count. Otherwise, returns an entropy count of 0.
+ */
+size_t rand_acquire_entropy_from_tsc(RAND_POOL *pool)
+{
+ unsigned char c;
+ int i;
+
+ if ((OPENSSL_ia32cap_P[0] & (1 << 4)) != 0) {
+ for (i = 0; i < TSC_READ_COUNT; i++) {
+ c = (unsigned char)(OPENSSL_rdtsc() & 0xFF);
+ rand_pool_add(pool, &c, 1, 4);
+ }
+ }
+ return rand_pool_entropy_available(pool);
+}
#endif
-#ifndef OPENSSL_NO_ENGINE
-/* non-NULL if default_RAND_meth is ENGINE-provided */
-static ENGINE *funct_ref = NULL;
+#ifdef OPENSSL_RAND_SEED_RDCPU
+size_t OPENSSL_ia32_rdseed_bytes(unsigned char *buf, size_t len);
+size_t OPENSSL_ia32_rdrand_bytes(unsigned char *buf, size_t len);
+
+/*
+ * Acquire entropy using Intel-specific cpu instructions
+ *
+ * Uses the RDSEED instruction if available, otherwise uses
+ * RDRAND if available.
+ *
+ * For the differences between RDSEED and RDRAND, and why RDSEED
+ * is the preferred choice, see https://goo.gl/oK3KcN
+ *
+ * Returns the total entropy count, if it exceeds the requested
+ * entropy count. Otherwise, returns an entropy count of 0.
+ */
+size_t rand_acquire_entropy_from_cpu(RAND_POOL *pool)
+{
+ size_t bytes_needed;
+ unsigned char *buffer;
+
+ bytes_needed = rand_pool_bytes_needed(pool, 1 /*entropy_factor*/);
+ if (bytes_needed > 0) {
+ buffer = rand_pool_add_begin(pool, bytes_needed);
+
+ if (buffer != NULL) {
+ /* Whichever comes first, use RDSEED, RDRAND or nothing */
+ if ((OPENSSL_ia32cap_P[2] & (1 << 18)) != 0) {
+ if (OPENSSL_ia32_rdseed_bytes(buffer, bytes_needed)
+ == bytes_needed) {
+ rand_pool_add_end(pool, bytes_needed, 8 * bytes_needed);
+ }
+ } else if ((OPENSSL_ia32cap_P[1] & (1 << (62 - 32))) != 0) {
+ if (OPENSSL_ia32_rdrand_bytes(buffer, bytes_needed)
+ == bytes_needed) {
+ rand_pool_add_end(pool, bytes_needed, 8 * bytes_needed);
+ }
+ } else {
+ rand_pool_add_end(pool, 0, 0);
+ }
+ }
+ }
+
+ return rand_pool_entropy_available(pool);
+}
+#endif
+
+#if 0
+/*
+ * Implements the get_entropy() callback (see RAND_DRBG_set_callbacks())
+ *
+ * If the DRBG has a parent, then the required amount of entropy input
+ * is fetched using the parent's RAND_DRBG_generate().
+ *
+ * Otherwise, the entropy is polled from the system entropy sources
+ * using rand_pool_acquire_entropy().
+ *
+ * If a random pool has been added to the DRBG using RAND_add(), then
+ * its entropy will be used up first.
+ */
+size_t rand_drbg_get_entropy(RAND_DRBG *drbg,
+ unsigned char **pout,
+ int entropy, size_t min_len, size_t max_len,
+ int prediction_resistance)
+{
+ size_t ret = 0;
+ size_t entropy_available = 0;
+ RAND_POOL *pool;
+
+ if (drbg->parent != NULL && drbg->strength > drbg->parent->strength) {
+ /*
+ * We currently don't support the algorithm from NIST SP 800-90C
+ * 10.1.2 to use a weaker DRBG as source
+ */
+ RANDerr(RAND_F_RAND_DRBG_GET_ENTROPY, RAND_R_PARENT_STRENGTH_TOO_WEAK);
+ return 0;
+ }
+
+ if (drbg->seed_pool != NULL) {
+ pool = drbg->seed_pool;
+ pool->entropy_requested = entropy;
+ } else {
+ pool = rand_pool_new(entropy, drbg->secure, min_len, max_len);
+ if (pool == NULL)
+ return 0;
+ }
+
+ if (drbg->parent != NULL) {
+ size_t bytes_needed = rand_pool_bytes_needed(pool, 1 /*entropy_factor*/);
+ unsigned char *buffer = rand_pool_add_begin(pool, bytes_needed);
+
+ if (buffer != NULL) {
+ size_t bytes = 0;
+
+ /*
+ * Get random data from parent. Include our address as additional input,
+ * in order to provide some additional distinction between different
+ * DRBG child instances.
+ * Our lock is already held, but we need to lock our parent before
+ * generating bits from it. (Note: taking the lock will be a no-op
+ * if locking if drbg->parent->lock == NULL.)
+ */
+ rand_drbg_lock(drbg->parent);
+ if (RAND_DRBG_generate(drbg->parent,
+ buffer, bytes_needed,
+ prediction_resistance,
+ (unsigned char *)&drbg, sizeof(drbg)) != 0)
+ bytes = bytes_needed;
+ drbg->reseed_next_counter
+ = tsan_load(&drbg->parent->reseed_prop_counter);
+ rand_drbg_unlock(drbg->parent);
+
+ rand_pool_add_end(pool, bytes, 8 * bytes);
+ entropy_available = rand_pool_entropy_available(pool);
+ }
+
+ } else {
+ /* Get entropy by polling system entropy sources. */
+ entropy_available = rand_pool_acquire_entropy(pool);
+ }
+
+ if (entropy_available > 0) {
+ ret = rand_pool_length(pool);
+ *pout = rand_pool_detach(pool);
+ }
+
+ if (drbg->seed_pool == NULL)
+ rand_pool_free(pool);
+ return ret;
+}
+
+/*
+ * Implements the cleanup_entropy() callback (see RAND_DRBG_set_callbacks())
+ *
+ */
+void rand_drbg_cleanup_entropy(RAND_DRBG *drbg,
+ unsigned char *out, size_t outlen)
+{
+ if (drbg->seed_pool == NULL) {
+ if (drbg->secure)
+ OPENSSL_secure_clear_free(out, outlen);
+ else
+ OPENSSL_clear_free(out, outlen);
+ }
+}
+
+/*
+ * Generate additional data that can be used for the drbg. The data does
+ * not need to contain entropy, but it's useful if it contains at least
+ * some bits that are unpredictable.
+ *
+ * Returns 0 on failure.
+ *
+ * On success it allocates a buffer at |*pout| and returns the length of
+ * the data. The buffer should get freed using OPENSSL_secure_clear_free().
+ */
+size_t rand_drbg_get_additional_data(RAND_POOL *pool, unsigned char **pout)
+{
+ size_t ret = 0;
+
+ if (rand_pool_add_additional_data(pool) == 0)
+ goto err;
+
+ ret = rand_pool_length(pool);
+ *pout = rand_pool_detach(pool);
+
+ err:
+ return ret;
+}
+
+void rand_drbg_cleanup_additional_data(RAND_POOL *pool, unsigned char *out)
+{
+ rand_pool_reattach(pool, out);
+}
+#endif
+
+#ifndef FIPS_MODULE
+DEFINE_RUN_ONCE_STATIC(do_rand_init)
+{
+# ifndef OPENSSL_NO_ENGINE
+ rand_engine_lock = CRYPTO_THREAD_lock_new();
+ if (rand_engine_lock == NULL)
+ return 0;
+# endif
+
+ rand_meth_lock = CRYPTO_THREAD_lock_new();
+ if (rand_meth_lock == NULL)
+ goto err;
+
+ if (!rand_pool_init())
+ goto err;
+
+ rand_inited = 1;
+ return 1;
+
+ err:
+ CRYPTO_THREAD_lock_free(rand_meth_lock);
+ rand_meth_lock = NULL;
+# ifndef OPENSSL_NO_ENGINE
+ CRYPTO_THREAD_lock_free(rand_engine_lock);
+ rand_engine_lock = NULL;
+# endif
+ return 0;
+}
+
+void rand_cleanup_int(void)
+{
+ const RAND_METHOD *meth = default_RAND_meth;
+
+ if (!rand_inited)
+ return;
+
+ if (meth != NULL && meth->cleanup != NULL)
+ meth->cleanup();
+ RAND_set_rand_method(NULL);
+ rand_pool_cleanup();
+# ifndef OPENSSL_NO_ENGINE
+ CRYPTO_THREAD_lock_free(rand_engine_lock);
+ rand_engine_lock = NULL;
+# endif
+ CRYPTO_THREAD_lock_free(rand_meth_lock);
+ rand_meth_lock = NULL;
+ rand_inited = 0;
+}
+
+/* TODO(3.0): Do we need to handle this somehow in the FIPS module? */
+/*
+ * RAND_close_seed_files() ensures that any seed file descriptors are
+ * closed after use.
+ */
+void RAND_keep_random_devices_open(int keep)
+{
+ if (RUN_ONCE(&rand_init, do_rand_init))
+ rand_pool_keep_random_devices_open(keep);
+}
+
+/*
+ * RAND_poll() reseeds the default RNG using random input
+ *
+ * The random input is obtained from polling various entropy
+ * sources which depend on the operating system and are
+ * configurable via the --with-rand-seed configure option.
+ */
+int RAND_poll(void)
+{
+ int ret = 0;
+
+ const RAND_METHOD *meth = RAND_get_rand_method();
+
+ if (meth == NULL)
+ return 0;
+
+ if (meth == RAND_OpenSSL()) {
+ /* fill random pool and seed the master DRBG */
+ RAND_DRBG *drbg = RAND_DRBG_get0_master();
+
+ if (drbg == NULL)
+ return 0;
+
+#if 0
+ ret = rand_drbg_restart(drbg, NULL, 0, 0);
#endif
-static const RAND_METHOD *default_RAND_meth = NULL;
+
+ return ret;
+
+ } else {
+ RAND_POOL *pool = NULL;
+
+ /* fill random pool and seed the current legacy RNG */
+ pool = rand_pool_new(RAND_DRBG_STRENGTH, 1,
+ (RAND_DRBG_STRENGTH + 7) / 8,
+ RAND_POOL_MAX_LENGTH);
+ if (pool == NULL)
+ return 0;
+#if 0
+ if (rand_pool_acquire_entropy(pool) == 0)
+ goto err;
+#endif
+ if (meth->add == NULL
+ || meth->add(rand_pool_buffer(pool),
+ rand_pool_length(pool),
+ (rand_pool_entropy(pool) / 8.0)) == 0)
+ goto err;
+
+ ret = 1;
+
+ err:
+ rand_pool_free(pool);
+ }
+
+ return ret;
+}
int RAND_set_rand_method(const RAND_METHOD *meth)
{
-#ifndef OPENSSL_NO_ENGINE
+ if (!RUN_ONCE(&rand_init, do_rand_init))
+ return 0;
+
+ CRYPTO_THREAD_write_lock(rand_meth_lock);
+# ifndef OPENSSL_NO_ENGINE
ENGINE_finish(funct_ref);
funct_ref = NULL;
-#endif
+# endif
default_RAND_meth = meth;
+ CRYPTO_THREAD_unlock(rand_meth_lock);
return 1;
}
+#endif /* FIPS_MODULE */
const RAND_METHOD *RAND_get_rand_method(void)
{
- if (!default_RAND_meth) {
-#ifndef OPENSSL_NO_ENGINE
- ENGINE *e = ENGINE_get_default_RAND();
- if (e) {
- default_RAND_meth = ENGINE_get_RAND(e);
- if (default_RAND_meth == NULL) {
- ENGINE_finish(e);
- e = NULL;
- }
- }
- if (e)
+#ifdef FIPS_MODULE
+ return NULL;
+#else
+ const RAND_METHOD *tmp_meth = NULL;
+
+ if (!RUN_ONCE(&rand_init, do_rand_init))
+ return NULL;
+
+ CRYPTO_THREAD_write_lock(rand_meth_lock);
+ if (default_RAND_meth == NULL) {
+# ifndef OPENSSL_NO_ENGINE
+ ENGINE *e;
+
+ /* If we have an engine that can do RAND, use it. */
+ if ((e = ENGINE_get_default_RAND()) != NULL
+ && (tmp_meth = ENGINE_get_RAND(e)) != NULL) {
funct_ref = e;
- else
-#endif
- default_RAND_meth = RAND_OpenSSL();
+ default_RAND_meth = tmp_meth;
+ } else {
+ ENGINE_finish(e);
+ default_RAND_meth = &rand_meth;
+ }
+# else
+ default_RAND_meth = &rand_meth;
+# endif
}
- return default_RAND_meth;
+ tmp_meth = default_RAND_meth;
+ CRYPTO_THREAD_unlock(rand_meth_lock);
+ return tmp_meth;
+#endif
}
-#ifndef OPENSSL_NO_ENGINE
+#if !defined(OPENSSL_NO_ENGINE) && !defined(FIPS_MODULE)
int RAND_set_rand_engine(ENGINE *engine)
{
const RAND_METHOD *tmp_meth = NULL;
- if (engine) {
+
+ if (!RUN_ONCE(&rand_init, do_rand_init))
+ return 0;
+
+ if (engine != NULL) {
if (!ENGINE_init(engine))
return 0;
tmp_meth = ENGINE_get_RAND(engine);
return 0;
}
}
+ CRYPTO_THREAD_write_lock(rand_engine_lock);
/* This function releases any prior ENGINE so call it first */
RAND_set_rand_method(tmp_meth);
funct_ref = engine;
+ CRYPTO_THREAD_unlock(rand_engine_lock);
return 1;
}
#endif
-void rand_cleanup_int(void)
+void RAND_seed(const void *buf, int num)
{
const RAND_METHOD *meth = RAND_get_rand_method();
- if (meth && meth->cleanup)
- meth->cleanup();
- RAND_set_rand_method(NULL);
+
+ if (meth != NULL && meth->seed != NULL)
+ meth->seed(buf, num);
}
-void RAND_seed(const void *buf, int num)
+void RAND_add(const void *buf, int num, double randomness)
{
const RAND_METHOD *meth = RAND_get_rand_method();
- if (meth && meth->seed)
- meth->seed(buf, num);
+
+ if (meth != NULL && meth->add != NULL)
+ meth->add(buf, num, randomness);
}
-void RAND_add(const void *buf, int num, double entropy)
+/*
+ * This function is not part of RAND_METHOD, so if we're not using
+ * the default method, then just call RAND_bytes(). Otherwise make
+ * sure we're instantiated and use the private DRBG.
+ */
+int RAND_priv_bytes_ex(OPENSSL_CTX *ctx, unsigned char *buf, int num)
{
+ RAND_DRBG *drbg;
const RAND_METHOD *meth = RAND_get_rand_method();
- if (meth && meth->add)
- meth->add(buf, num, entropy);
+
+ if (meth != NULL && meth != RAND_OpenSSL()) {
+ if (meth->bytes != NULL)
+ return meth->bytes(buf, num);
+ RANDerr(RAND_F_RAND_PRIV_BYTES_EX, RAND_R_FUNC_NOT_IMPLEMENTED);
+ return -1;
+ }
+
+ drbg = OPENSSL_CTX_get0_private_drbg(ctx);
+ if (drbg != NULL)
+ return RAND_DRBG_bytes(drbg, buf, num);
+
+ return 0;
}
-int RAND_bytes(unsigned char *buf, int num)
+int RAND_priv_bytes(unsigned char *buf, int num)
{
+ return RAND_priv_bytes_ex(NULL, buf, num);
+}
+
+int RAND_bytes_ex(OPENSSL_CTX *ctx, unsigned char *buf, int num)
+{
+ RAND_DRBG *drbg;
const RAND_METHOD *meth = RAND_get_rand_method();
- if (meth && meth->bytes)
- return meth->bytes(buf, num);
- return (-1);
+
+ if (meth != NULL && meth != RAND_OpenSSL()) {
+ if (meth->bytes != NULL)
+ return meth->bytes(buf, num);
+ RANDerr(RAND_F_RAND_BYTES_EX, RAND_R_FUNC_NOT_IMPLEMENTED);
+ return -1;
+ }
+
+ drbg = OPENSSL_CTX_get0_public_drbg(ctx);
+ if (drbg != NULL)
+ return RAND_DRBG_bytes(drbg, buf, num);
+
+ return 0;
+}
+
+int RAND_bytes(unsigned char *buf, int num)
+{
+ return RAND_bytes_ex(NULL, buf, num);
}
-#if OPENSSL_API_COMPAT < 0x10100000L
+#if !defined(OPENSSL_NO_DEPRECATED_1_1_0) && !defined(FIPS_MODULE)
int RAND_pseudo_bytes(unsigned char *buf, int num)
{
const RAND_METHOD *meth = RAND_get_rand_method();
- if (meth && meth->pseudorand)
+
+ if (meth != NULL && meth->pseudorand != NULL)
return meth->pseudorand(buf, num);
- return (-1);
+ RANDerr(RAND_F_RAND_PSEUDO_BYTES, RAND_R_FUNC_NOT_IMPLEMENTED);
+ return -1;
}
#endif
int RAND_status(void)
{
const RAND_METHOD *meth = RAND_get_rand_method();
- if (meth && meth->status)
+
+ if (meth != NULL && meth->status != NULL)
return meth->status();
return 0;
}