/*
- * Copyright 1995-2017 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2018 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_int.h"
+#include "crypto/rand.h"
#include <openssl/engine.h>
#include "internal/thread_once.h"
-#include "rand_lcl.h"
-#ifdef OPENSSL_SYS_UNIX
-# include <sys/types.h>
-# include <unistd.h>
-# include <sys/time.h>
-#endif
+#include "rand_local.h"
#include "e_os.h"
-#ifndef OPENSSL_NO_ENGINE
+#ifndef FIPS_MODE
+# ifndef OPENSSL_NO_ENGINE
/* non-NULL if default_RAND_meth is ENGINE-provided */
static ENGINE *funct_ref;
static CRYPTO_RWLOCK *rand_engine_lock;
-#endif
+# endif
static CRYPTO_RWLOCK *rand_meth_lock;
static const RAND_METHOD *default_RAND_meth;
static CRYPTO_ONCE rand_init = CRYPTO_ONCE_STATIC_INIT;
-int rand_fork_count;
+static int rand_inited = 0;
+#endif /* FIPS_MODE */
#ifdef OPENSSL_RAND_SEED_RDTSC
/*
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);
+ rand_pool_add(pool, &c, 1, 4);
}
}
- return RAND_POOL_entropy_available(pool);
+ return rand_pool_entropy_available(pool);
}
#endif
size_t OPENSSL_ia32_rdseed_bytes(unsigned char *buf, size_t len);
size_t OPENSSL_ia32_rdrand_bytes(unsigned char *buf, size_t len);
-extern unsigned int OPENSSL_ia32cap_P[];
-
/*
* Acquire entropy using Intel-specific cpu instructions
*
size_t bytes_needed;
unsigned char *buffer;
- bytes_needed = RAND_POOL_bytes_needed(pool, 8 /*entropy_per_byte*/);
+ bytes_needed = rand_pool_bytes_needed(pool, 1 /*entropy_factor*/);
if (bytes_needed > 0) {
- buffer = RAND_POOL_add_begin(pool, bytes_needed);
+ buffer = rand_pool_add_begin(pool, bytes_needed);
if (buffer != NULL) {
-
- /* If RDSEED is available, use that. */
+ /* 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)
- return RAND_POOL_add_end(pool,
- bytes_needed,
- 8 * bytes_needed);
- }
-
- /* Second choice is RDRAND. */
- if ((OPENSSL_ia32cap_P[1] & (1 << (62 - 32))) != 0) {
+ == 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)
- return RAND_POOL_add_end(pool,
- bytes_needed,
- 8 * 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_add_end(pool, 0, 0);
}
}
- return RAND_POOL_entropy_available(pool);
+ return rand_pool_entropy_available(pool);
}
#endif
* is fetched using the parent's RAND_DRBG_generate().
*
* Otherwise, the entropy is polled from the system entropy sources
- * using RAND_POOL_acquire_entropy().
+ * 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)
+ 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 = RAND_POOL_new(entropy, min_len, max_len);
+ RAND_POOL *pool;
- if (pool == NULL)
+ 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->pool) {
- RAND_POOL_add(pool,
- RAND_POOL_buffer(drbg->pool),
- RAND_POOL_length(drbg->pool),
- RAND_POOL_entropy(drbg->pool));
- RAND_POOL_free(drbg->pool);
- drbg->pool = NULL;
+ 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) {
- size_t bytes_needed = RAND_POOL_bytes_needed(pool, 8);
- unsigned char *buffer = RAND_POOL_add_begin(pool, bytes_needed);
+ 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 from parent, include our state as additional input.
+ * 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.
+ * generating bits from it. (Note: taking the lock will be a no-op
+ * if locking if drbg->parent->lock == NULL.)
*/
- if (drbg->parent->lock)
- CRYPTO_THREAD_write_lock(drbg->parent->lock);
+ rand_drbg_lock(drbg->parent);
if (RAND_DRBG_generate(drbg->parent,
buffer, bytes_needed,
- 0,
- (unsigned char *)drbg, sizeof(*drbg)) != 0)
+ prediction_resistance,
+ (unsigned char *)&drbg, sizeof(drbg)) != 0)
bytes = bytes_needed;
- if (drbg->parent->lock)
- CRYPTO_THREAD_unlock(drbg->parent->lock);
+ drbg->reseed_next_counter
+ = tsan_load(&drbg->parent->reseed_prop_counter);
+ rand_drbg_unlock(drbg->parent);
- entropy_available = RAND_POOL_add_end(pool, bytes, 8 * bytes);
+ 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);
+ entropy_available = rand_pool_acquire_entropy(pool);
}
if (entropy_available > 0) {
- ret = RAND_POOL_length(pool);
- *pout = RAND_POOL_detach(pool);
+ ret = rand_pool_length(pool);
+ *pout = rand_pool_detach(pool);
}
- RAND_POOL_free(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
* 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(unsigned char **pout, size_t max_len)
+size_t rand_drbg_get_additional_data(RAND_POOL *pool, unsigned char **pout)
{
- RAND_POOL *pool;
- CRYPTO_THREAD_ID thread_id;
- size_t len;
-#ifdef OPENSSL_SYS_UNIX
- pid_t pid;
- struct timespec ts;
-#elif defined(OPENSSL_SYS_WIN32)
- DWORD pid;
- FILETIME ft;
- LARGE_INTEGER pc;
-#endif
- uint32_t tsc = 0;
-
- pool = RAND_POOL_new(0, 0, max_len);
- if (pool == NULL)
- return 0;
-
-#ifdef OPENSSL_SYS_UNIX
- pid = getpid();
- RAND_POOL_add(pool, (unsigned char *)&pid, sizeof(pid), 0);
-#elif defined(OPENSSL_SYS_WIN32)
- pid = GetCurrentProcessId();
- RAND_POOL_add(pool, (unsigned char *)&pid, sizeof(pid), 0);
-#endif
-
- thread_id = CRYPTO_THREAD_get_current_id();
- if (thread_id != 0)
- RAND_POOL_add(pool, (unsigned char *)&thread_id, sizeof(thread_id), 0);
-
-#ifdef OPENSSL_CPUID_OBJ
- tsc = OPENSSL_rdtsc();
- if (tsc != 0)
- RAND_POOL_add(pool, (unsigned char *)&tsc, sizeof(tsc), 0);
-#endif
-
-#ifdef OPENSSL_SYS_UNIX
- if (tsc == 0 && clock_gettime(CLOCK_MONOTONIC, &ts) == 0)
- RAND_POOL_add(pool, (unsigned char *)&ts, sizeof(ts), 0);
- if (clock_gettime(CLOCK_REALTIME, &ts) == 0)
- RAND_POOL_add(pool, (unsigned char *)&ts, sizeof(ts), 0);
-#elif defined(OPENSSL_SYS_WIN32)
- if (tsc == 0 && QueryPerformanceCounter(&pc) != 0)
- RAND_POOL_add(pool, (unsigned char *)&pc, sizeof(pc), 0);
- GetSystemTimeAsFileTime(&ft);
- RAND_POOL_add(pool, (unsigned char *)&ft, sizeof(ft), 0);
-#endif
-
- /* TODO: Use RDSEED? */
+ size_t ret = 0;
- len = RAND_POOL_length(pool);
- if (len != 0)
- *pout = RAND_POOL_detach(pool);
- RAND_POOL_free(pool);
+ if (rand_pool_add_additional_data(pool) == 0)
+ goto err;
- return len;
-}
+ ret = rand_pool_length(pool);
+ *pout = rand_pool_detach(pool);
-/*
- * Implements the cleanup_entropy() callback (see RAND_DRBG_set_callbacks())
- *
- */
-void rand_drbg_cleanup_entropy(RAND_DRBG *drbg,
- unsigned char *out, size_t outlen)
-{
- OPENSSL_secure_clear_free(out, outlen);
+ err:
+ return ret;
}
-void rand_fork()
+void rand_drbg_cleanup_additional_data(RAND_POOL *pool, unsigned char *out)
{
- rand_fork_count++;
+ rand_pool_reattach(pool, out);
}
+#ifndef FIPS_MODE
DEFINE_RUN_ONCE_STATIC(do_rand_init)
{
- int ret = 1;
+# ifndef OPENSSL_NO_ENGINE
+ rand_engine_lock = CRYPTO_THREAD_lock_new();
+ if (rand_engine_lock == NULL)
+ return 0;
+# endif
-#ifndef OPENSSL_NO_ENGINE
- rand_engine_lock = CRYPTO_THREAD_glock_new("rand_engine");
- ret &= rand_engine_lock != NULL;
-#endif
- rand_meth_lock = CRYPTO_THREAD_glock_new("rand_meth");
- ret &= rand_meth_lock != NULL;
+ rand_meth_lock = CRYPTO_THREAD_lock_new();
+ if (rand_meth_lock == NULL)
+ goto err;
- return ret;
+ 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);
-#ifndef OPENSSL_NO_ENGINE
+ rand_pool_cleanup();
+# ifndef OPENSSL_NO_ENGINE
CRYPTO_THREAD_lock_free(rand_engine_lock);
-#endif
+ 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);
}
/*
{
int ret = 0;
- RAND_POOL *pool = NULL;
-
const RAND_METHOD *meth = RAND_get_rand_method();
if (meth == RAND_OpenSSL()) {
if (drbg == NULL)
return 0;
- CRYPTO_THREAD_write_lock(drbg->lock);
+ rand_drbg_lock(drbg);
ret = rand_drbg_restart(drbg, NULL, 0, 0);
- CRYPTO_THREAD_unlock(drbg->lock);
+ rand_drbg_unlock(drbg);
return ret;
} else {
+ RAND_POOL *pool = NULL;
+
/* fill random pool and seed the current legacy RNG */
- pool = RAND_POOL_new(RAND_DRBG_STRENGTH,
- RAND_DRBG_STRENGTH / 8,
- DRBG_MINMAX_FACTOR * (RAND_DRBG_STRENGTH / 8));
+ pool = rand_pool_new(RAND_DRBG_STRENGTH, 1,
+ (RAND_DRBG_STRENGTH + 7) / 8,
+ RAND_POOL_MAX_LENGTH);
if (pool == NULL)
return 0;
- if (RAND_POOL_acquire_entropy(pool) == 0)
+ if (rand_pool_acquire_entropy(pool) == 0)
goto err;
if (meth->add == NULL
- || meth->add(RAND_POOL_buffer(pool),
- RAND_POOL_length(pool),
- (RAND_POOL_entropy(pool) / 8.0)) == 0)
+ || 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);
}
-err:
- RAND_POOL_free(pool);
return ret;
}
-
-/*
- * The 'random pool' acts as a dumb container for collecting random
- * input from various entropy sources. The pool has no knowledge about
- * whether its randomness is fed into a legacy RAND_METHOD via RAND_add()
- * or into a new style RAND_DRBG. It is the callers duty to 1) initialize the
- * random pool, 2) pass it to the polling callbacks, 3) seed the RNG, and
- * 4) cleanup the random pool again.
- *
- * The random pool contains no locking mechanism because its scope and
- * lifetime is intended to be restricted to a single stack frame.
- */
-struct rand_pool_st {
- unsigned char *buffer; /* points to the beginning of the random pool */
- size_t len; /* current number of random bytes contained in the pool */
-
- size_t min_len; /* minimum number of random bytes requested */
- size_t max_len; /* maximum number of random bytes (allocated buffer size) */
- size_t entropy; /* current entropy count in bits */
- size_t requested_entropy; /* requested entropy count in bits */
-};
+#endif /* FIPS_MODE */
/*
* Allocate memory and initialize a new random pool
*/
-RAND_POOL *RAND_POOL_new(int entropy, size_t min_len, size_t max_len)
+RAND_POOL *rand_pool_new(int entropy_requested, int secure,
+ size_t min_len, size_t max_len)
{
RAND_POOL *pool = OPENSSL_zalloc(sizeof(*pool));
+ size_t min_alloc_size = RAND_POOL_MIN_ALLOCATION(secure);
if (pool == NULL) {
RANDerr(RAND_F_RAND_POOL_NEW, ERR_R_MALLOC_FAILURE);
- goto err;
+ return NULL;
}
pool->min_len = min_len;
- pool->max_len = max_len;
+ pool->max_len = (max_len > RAND_POOL_MAX_LENGTH) ?
+ RAND_POOL_MAX_LENGTH : max_len;
+ pool->alloc_len = min_len < min_alloc_size ? min_alloc_size : min_len;
+ if (pool->alloc_len > pool->max_len)
+ pool->alloc_len = pool->max_len;
+
+ if (secure)
+ pool->buffer = OPENSSL_secure_zalloc(pool->alloc_len);
+ else
+ pool->buffer = OPENSSL_zalloc(pool->alloc_len);
- pool->buffer = OPENSSL_secure_zalloc(pool->max_len);
if (pool->buffer == NULL) {
RANDerr(RAND_F_RAND_POOL_NEW, ERR_R_MALLOC_FAILURE);
goto err;
}
- pool->requested_entropy = entropy;
+ pool->entropy_requested = entropy_requested;
+ pool->secure = secure;
return pool;
return NULL;
}
+/*
+ * Attach new random pool to the given buffer
+ *
+ * This function is intended to be used only for feeding random data
+ * provided by RAND_add() and RAND_seed() into the <master> DRBG.
+ */
+RAND_POOL *rand_pool_attach(const unsigned char *buffer, size_t len,
+ size_t entropy)
+{
+ RAND_POOL *pool = OPENSSL_zalloc(sizeof(*pool));
+
+ if (pool == NULL) {
+ RANDerr(RAND_F_RAND_POOL_ATTACH, ERR_R_MALLOC_FAILURE);
+ return NULL;
+ }
+
+ /*
+ * The const needs to be cast away, but attached buffers will not be
+ * modified (in contrary to allocated buffers which are zeroed and
+ * freed in the end).
+ */
+ pool->buffer = (unsigned char *) buffer;
+ pool->len = len;
+
+ pool->attached = 1;
+
+ pool->min_len = pool->max_len = pool->alloc_len = pool->len;
+ pool->entropy = entropy;
+
+ return pool;
+}
+
/*
* Free |pool|, securely erasing its buffer.
*/
-void RAND_POOL_free(RAND_POOL *pool)
+void rand_pool_free(RAND_POOL *pool)
{
if (pool == NULL)
return;
- OPENSSL_secure_clear_free(pool->buffer, pool->max_len);
+ /*
+ * Although it would be advisable from a cryptographical viewpoint,
+ * we are not allowed to clear attached buffers, since they are passed
+ * to rand_pool_attach() as `const unsigned char*`.
+ * (see corresponding comment in rand_pool_attach()).
+ */
+ if (!pool->attached) {
+ if (pool->secure)
+ OPENSSL_secure_clear_free(pool->buffer, pool->alloc_len);
+ else
+ OPENSSL_clear_free(pool->buffer, pool->alloc_len);
+ }
+
OPENSSL_free(pool);
}
/*
* Return the |pool|'s buffer to the caller (readonly).
*/
-const unsigned char *RAND_POOL_buffer(RAND_POOL *pool)
+const unsigned char *rand_pool_buffer(RAND_POOL *pool)
{
return pool->buffer;
}
/*
* Return the |pool|'s entropy to the caller.
*/
-size_t RAND_POOL_entropy(RAND_POOL *pool)
+size_t rand_pool_entropy(RAND_POOL *pool)
{
return pool->entropy;
}
/*
* Return the |pool|'s buffer length to the caller.
*/
-size_t RAND_POOL_length(RAND_POOL *pool)
+size_t rand_pool_length(RAND_POOL *pool)
{
return pool->len;
}
/*
* Detach the |pool| buffer and return it to the caller.
* It's the responsibility of the caller to free the buffer
- * using OPENSSL_secure_clear_free().
+ * using OPENSSL_secure_clear_free() or to re-attach it
+ * again to the pool using rand_pool_reattach().
*/
-unsigned char *RAND_POOL_detach(RAND_POOL *pool)
+unsigned char *rand_pool_detach(RAND_POOL *pool)
{
unsigned char *ret = pool->buffer;
pool->buffer = NULL;
+ pool->entropy = 0;
return ret;
}
+/*
+ * Re-attach the |pool| buffer. It is only allowed to pass
+ * the |buffer| which was previously detached from the same pool.
+ */
+void rand_pool_reattach(RAND_POOL *pool, unsigned char *buffer)
+{
+ pool->buffer = buffer;
+ OPENSSL_cleanse(pool->buffer, pool->len);
+ pool->len = 0;
+}
/*
- * If every byte of the input contains |entropy_per_bytes| bits of entropy,
- * how many bytes does one need to obtain at least |bits| bits of entropy?
+ * If |entropy_factor| bits contain 1 bit of entropy, how many bytes does one
+ * need to obtain at least |bits| bits of entropy?
*/
-#define ENTROPY_TO_BYTES(bits, entropy_per_bytes) \
- (((bits) + ((entropy_per_bytes) - 1))/(entropy_per_bytes))
+#define ENTROPY_TO_BYTES(bits, entropy_factor) \
+ (((bits) * (entropy_factor) + 7) / 8)
/*
* |entropy| if the entropy count and buffer size is large enough
* 0 otherwise
*/
-size_t RAND_POOL_entropy_available(RAND_POOL *pool)
+size_t rand_pool_entropy_available(RAND_POOL *pool)
{
- if (pool->entropy < pool->requested_entropy)
+ if (pool->entropy < pool->entropy_requested)
return 0;
if (pool->len < pool->min_len)
* the random pool.
*/
-size_t RAND_POOL_entropy_needed(RAND_POOL *pool)
+size_t rand_pool_entropy_needed(RAND_POOL *pool)
{
- if (pool->entropy < pool->requested_entropy)
- return pool->requested_entropy - pool->entropy;
+ if (pool->entropy < pool->entropy_requested)
+ return pool->entropy_requested - pool->entropy;
return 0;
}
+/* Increase the allocation size -- not usable for an attached pool */
+static int rand_pool_grow(RAND_POOL *pool, size_t len)
+{
+ if (len > pool->alloc_len - pool->len) {
+ unsigned char *p;
+ const size_t limit = pool->max_len / 2;
+ size_t newlen = pool->alloc_len;
+
+ if (pool->attached || len > pool->max_len - pool->len) {
+ RANDerr(RAND_F_RAND_POOL_GROW, ERR_R_INTERNAL_ERROR);
+ return 0;
+ }
+
+ do
+ newlen = newlen < limit ? newlen * 2 : pool->max_len;
+ while (len > newlen - pool->len);
+
+ if (pool->secure)
+ p = OPENSSL_secure_zalloc(newlen);
+ else
+ p = OPENSSL_zalloc(newlen);
+ if (p == NULL) {
+ RANDerr(RAND_F_RAND_POOL_GROW, ERR_R_MALLOC_FAILURE);
+ return 0;
+ }
+ memcpy(p, pool->buffer, pool->len);
+ if (pool->secure)
+ OPENSSL_secure_clear_free(pool->buffer, pool->alloc_len);
+ else
+ OPENSSL_clear_free(pool->buffer, pool->alloc_len);
+ pool->buffer = p;
+ pool->alloc_len = newlen;
+ }
+ return 1;
+}
+
/*
* Returns the number of bytes needed to fill the pool, assuming
- * the input has 'entropy_per_byte' entropy bits per byte.
+ * the input has 1 / |entropy_factor| entropy bits per data bit.
* In case of an error, 0 is returned.
*/
-size_t RAND_POOL_bytes_needed(RAND_POOL *pool, unsigned int entropy_per_byte)
+size_t rand_pool_bytes_needed(RAND_POOL *pool, unsigned int entropy_factor)
{
size_t bytes_needed;
- size_t entropy_needed = RAND_POOL_entropy_needed(pool);
+ size_t entropy_needed = rand_pool_entropy_needed(pool);
- if (entropy_per_byte < 1 || entropy_per_byte > 8) {
+ if (entropy_factor < 1) {
RANDerr(RAND_F_RAND_POOL_BYTES_NEEDED, RAND_R_ARGUMENT_OUT_OF_RANGE);
return 0;
}
- bytes_needed = ENTROPY_TO_BYTES(entropy_needed, entropy_per_byte);
+ bytes_needed = ENTROPY_TO_BYTES(entropy_needed, entropy_factor);
if (bytes_needed > pool->max_len - pool->len) {
/* not enough space left */
/* to meet the min_len requirement */
bytes_needed = pool->min_len - pool->len;
+ /*
+ * Make sure the buffer is large enough for the requested amount
+ * of data. This guarantees that existing code patterns where
+ * rand_pool_add_begin, rand_pool_add_end or rand_pool_add
+ * are used to collect entropy data without any error handling
+ * whatsoever, continue to be valid.
+ * Furthermore if the allocation here fails once, make sure that
+ * we don't fall back to a less secure or even blocking random source,
+ * as that could happen by the existing code patterns.
+ * This is not a concern for additional data, therefore that
+ * is not needed if rand_pool_grow fails in other places.
+ */
+ if (!rand_pool_grow(pool, bytes_needed)) {
+ /* persistent error for this pool */
+ pool->max_len = pool->len = 0;
+ return 0;
+ }
+
return bytes_needed;
}
/* Returns the remaining number of bytes available */
-size_t RAND_POOL_bytes_remaining(RAND_POOL *pool)
+size_t rand_pool_bytes_remaining(RAND_POOL *pool)
{
return pool->max_len - pool->len;
}
* random input which contains at least |entropy| bits of
* randomness.
*
- * Return available amount of entropy after this operation.
- * (see RAND_POOL_entropy_available(pool))
+ * Returns 1 if the added amount is adequate, otherwise 0
*/
-size_t RAND_POOL_add(RAND_POOL *pool,
- const unsigned char *buffer, size_t len, size_t entropy)
+int rand_pool_add(RAND_POOL *pool,
+ const unsigned char *buffer, size_t len, size_t entropy)
{
if (len > pool->max_len - pool->len) {
RANDerr(RAND_F_RAND_POOL_ADD, RAND_R_ENTROPY_INPUT_TOO_LONG);
return 0;
}
+ if (pool->buffer == NULL) {
+ RANDerr(RAND_F_RAND_POOL_ADD, ERR_R_INTERNAL_ERROR);
+ return 0;
+ }
+
if (len > 0) {
+ /*
+ * This is to protect us from accidentally passing the buffer
+ * returned from rand_pool_add_begin.
+ * The check for alloc_len makes sure we do not compare the
+ * address of the end of the allocated memory to something
+ * different, since that comparison would have an
+ * indeterminate result.
+ */
+ if (pool->alloc_len > pool->len && pool->buffer + pool->len == buffer) {
+ RANDerr(RAND_F_RAND_POOL_ADD, ERR_R_INTERNAL_ERROR);
+ return 0;
+ }
+ /*
+ * We have that only for cases when a pool is used to collect
+ * additional data.
+ * For entropy data, as long as the allocation request stays within
+ * the limits given by rand_pool_bytes_needed this rand_pool_grow
+ * below is guaranteed to succeed, thus no allocation happens.
+ */
+ if (!rand_pool_grow(pool, len))
+ return 0;
memcpy(pool->buffer + pool->len, buffer, len);
pool->len += len;
pool->entropy += entropy;
}
- return RAND_POOL_entropy_available(pool);
+ return 1;
}
/*
* If |len| == 0 this is considered a no-op and a NULL pointer
* is returned without producing an error message.
*
- * After updating the buffer, RAND_POOL_add_end() needs to be called
+ * After updating the buffer, rand_pool_add_end() needs to be called
* to finish the udpate operation (see next comment).
*/
-unsigned char *RAND_POOL_add_begin(RAND_POOL *pool, size_t len)
+unsigned char *rand_pool_add_begin(RAND_POOL *pool, size_t len)
{
if (len == 0)
return NULL;
return NULL;
}
+ if (pool->buffer == NULL) {
+ RANDerr(RAND_F_RAND_POOL_ADD_BEGIN, ERR_R_INTERNAL_ERROR);
+ return NULL;
+ }
+
+ /*
+ * As long as the allocation request stays within the limits given
+ * by rand_pool_bytes_needed this rand_pool_grow below is guaranteed
+ * to succeed, thus no allocation happens.
+ * We have that only for cases when a pool is used to collect
+ * additional data. Then the buffer might need to grow here,
+ * and of course the caller is responsible to check the return
+ * value of this function.
+ */
+ if (!rand_pool_grow(pool, len))
+ return NULL;
+
return pool->buffer + pool->len;
}
* Finish to add random bytes to the random pool in-place.
*
* Finishes an in-place update of the random pool started by
- * RAND_POOL_add_begin() (see previous comment).
+ * rand_pool_add_begin() (see previous comment).
* It is expected that |len| bytes of random input have been added
* to the buffer which contain at least |entropy| bits of randomness.
* It is allowed to add less bytes than originally reserved.
*/
-size_t RAND_POOL_add_end(RAND_POOL *pool, size_t len, size_t entropy)
+int rand_pool_add_end(RAND_POOL *pool, size_t len, size_t entropy)
{
- if (len > pool->max_len - pool->len) {
+ if (len > pool->alloc_len - pool->len) {
RANDerr(RAND_F_RAND_POOL_ADD_END, RAND_R_RANDOM_POOL_OVERFLOW);
return 0;
}
pool->entropy += entropy;
}
- return RAND_POOL_entropy_available(pool);
+ return 1;
}
+#ifndef FIPS_MODE
int RAND_set_rand_method(const RAND_METHOD *meth)
{
if (!RUN_ONCE(&rand_init, do_rand_init))
return 0;
CRYPTO_THREAD_write_lock(rand_meth_lock);
-#ifndef OPENSSL_NO_ENGINE
+# 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
const RAND_METHOD *RAND_get_rand_method(void)
{
+#ifdef FIPS_MODE
+ return NULL;
+#else
const RAND_METHOD *tmp_meth = NULL;
if (!RUN_ONCE(&rand_init, do_rand_init))
CRYPTO_THREAD_write_lock(rand_meth_lock);
if (default_RAND_meth == NULL) {
-#ifndef OPENSSL_NO_ENGINE
+# ifndef OPENSSL_NO_ENGINE
ENGINE *e;
/* If we have an engine that can do RAND, use it. */
ENGINE_finish(e);
default_RAND_meth = &rand_meth;
}
-#else
+# else
default_RAND_meth = &rand_meth;
-#endif
+# endif
}
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_MODE)
int RAND_set_rand_engine(ENGINE *engine)
{
const RAND_METHOD *tmp_meth = NULL;
* the default method, then just call RAND_bytes(). Otherwise make
* sure we're instantiated and use the private DRBG.
*/
-int RAND_priv_bytes(unsigned char *buf, int num)
+int rand_priv_bytes_ex(OPENSSL_CTX *ctx, unsigned char *buf, int num)
{
- const RAND_METHOD *meth = RAND_get_rand_method();
RAND_DRBG *drbg;
int ret;
+ const RAND_METHOD *meth = RAND_get_rand_method();
if (meth != RAND_OpenSSL())
- return RAND_bytes(buf, num);
+ return meth->bytes(buf, num);
- drbg = RAND_DRBG_get0_private();
+ drbg = OPENSSL_CTX_get0_private_drbg(ctx);
if (drbg == NULL)
return 0;
- /* We have to lock the DRBG before generating bits from it. */
- CRYPTO_THREAD_write_lock(drbg->lock);
- ret = RAND_DRBG_generate(drbg, buf, num, 0, NULL, 0);
- CRYPTO_THREAD_unlock(drbg->lock);
+ ret = RAND_DRBG_bytes(drbg, buf, num);
return ret;
}
-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;
+ int ret;
const RAND_METHOD *meth = RAND_get_rand_method();
- if (meth->bytes != NULL)
- return meth->bytes(buf, num);
- RANDerr(RAND_F_RAND_BYTES, RAND_R_FUNC_NOT_IMPLEMENTED);
- return -1;
+ if (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 0;
+
+ ret = RAND_DRBG_bytes(drbg, buf, num);
+ return ret;
+}
+
+int RAND_bytes(unsigned char *buf, int num)
+{
+ return rand_bytes_ex(NULL, buf, num);
}
-#if OPENSSL_API_COMPAT < 0x10100000L
+#if !OPENSSL_API_1_1_0 && !defined(FIPS_MODE)
int RAND_pseudo_bytes(unsigned char *buf, int num)
{
const RAND_METHOD *meth = RAND_get_rand_method();