openssl/crypto/threads_none.c
Neil Horman 7e45ac6891 Add CRYPTO_atomic_store api
Generally we can get away with just using CRYPTO_atomic_load to do
stores by reversing the source and target variables, but doing so
creates a problem for the thread sanitizer as CRYPTO_atomic_load hard
codes an __ATOMIC_ACQUIRE constraint, which confuses tsan into thinking
that loads and stores aren't properly ordered, leading to RAW/WAR
hazzards getting reported.  Instead create a CRYPTO_atomic_store api
that is identical to the load variant, save for the fact that the value
is a unit64_t rather than a pointer that gets stored using an
__ATOMIC_RELEASE constraint, satisfying tsan.

Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/23671)
2024-04-24 12:03:03 +10:00

257 lines
4.7 KiB
C

/*
* Copyright 2016-2024 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 <openssl/crypto.h>
#include "internal/cryptlib.h"
#include "internal/rcu.h"
#include "rcu_internal.h"
#if !defined(OPENSSL_THREADS) || defined(CRYPTO_TDEBUG)
# if defined(OPENSSL_SYS_UNIX)
# include <sys/types.h>
# include <unistd.h>
# endif
struct rcu_lock_st {
struct rcu_cb_item *cb_items;
};
CRYPTO_RCU_LOCK *ossl_rcu_lock_new(int num_writers, OSSL_LIB_CTX *ctx)
{
struct rcu_lock_st *lock;
lock = OPENSSL_zalloc(sizeof(*lock));
return lock;
}
void ossl_rcu_lock_free(CRYPTO_RCU_LOCK *lock)
{
OPENSSL_free(lock);
}
void ossl_rcu_read_lock(CRYPTO_RCU_LOCK *lock)
{
return;
}
void ossl_rcu_write_lock(CRYPTO_RCU_LOCK *lock)
{
return;
}
void ossl_rcu_write_unlock(CRYPTO_RCU_LOCK *lock)
{
return;
}
void ossl_rcu_read_unlock(CRYPTO_RCU_LOCK *lock)
{
return;
}
void ossl_synchronize_rcu(CRYPTO_RCU_LOCK *lock)
{
struct rcu_cb_item *items = lock->cb_items;
struct rcu_cb_item *tmp;
lock->cb_items = NULL;
while (items != NULL) {
tmp = items->next;
items->fn(items->data);
OPENSSL_free(items);
items = tmp;
}
}
int ossl_rcu_call(CRYPTO_RCU_LOCK *lock, rcu_cb_fn cb, void *data)
{
struct rcu_cb_item *new = OPENSSL_zalloc(sizeof(*new));
if (new == NULL)
return 0;
new->fn = cb;
new->data = data;
new->next = lock->cb_items;
lock->cb_items = new;
return 1;
}
void *ossl_rcu_uptr_deref(void **p)
{
return (void *)*p;
}
void ossl_rcu_assign_uptr(void **p, void **v)
{
*(void **)p = *(void **)v;
}
CRYPTO_RWLOCK *CRYPTO_THREAD_lock_new(void)
{
CRYPTO_RWLOCK *lock;
if ((lock = CRYPTO_zalloc(sizeof(unsigned int), NULL, 0)) == NULL)
/* Don't set error, to avoid recursion blowup. */
return NULL;
*(unsigned int *)lock = 1;
return lock;
}
__owur int CRYPTO_THREAD_read_lock(CRYPTO_RWLOCK *lock)
{
if (!ossl_assert(*(unsigned int *)lock == 1))
return 0;
return 1;
}
__owur int CRYPTO_THREAD_write_lock(CRYPTO_RWLOCK *lock)
{
if (!ossl_assert(*(unsigned int *)lock == 1))
return 0;
return 1;
}
int CRYPTO_THREAD_unlock(CRYPTO_RWLOCK *lock)
{
if (!ossl_assert(*(unsigned int *)lock == 1))
return 0;
return 1;
}
void CRYPTO_THREAD_lock_free(CRYPTO_RWLOCK *lock) {
if (lock == NULL)
return;
*(unsigned int *)lock = 0;
OPENSSL_free(lock);
return;
}
int CRYPTO_THREAD_run_once(CRYPTO_ONCE *once, void (*init)(void))
{
if (*once != 0)
return 1;
init();
*once = 1;
return 1;
}
#define OPENSSL_CRYPTO_THREAD_LOCAL_KEY_MAX 256
static void *thread_local_storage[OPENSSL_CRYPTO_THREAD_LOCAL_KEY_MAX];
int CRYPTO_THREAD_init_local(CRYPTO_THREAD_LOCAL *key, void (*cleanup)(void *))
{
static unsigned int thread_local_key = 0;
if (thread_local_key >= OPENSSL_CRYPTO_THREAD_LOCAL_KEY_MAX)
return 0;
*key = thread_local_key++;
thread_local_storage[*key] = NULL;
return 1;
}
void *CRYPTO_THREAD_get_local(CRYPTO_THREAD_LOCAL *key)
{
if (*key >= OPENSSL_CRYPTO_THREAD_LOCAL_KEY_MAX)
return NULL;
return thread_local_storage[*key];
}
int CRYPTO_THREAD_set_local(CRYPTO_THREAD_LOCAL *key, void *val)
{
if (*key >= OPENSSL_CRYPTO_THREAD_LOCAL_KEY_MAX)
return 0;
thread_local_storage[*key] = val;
return 1;
}
int CRYPTO_THREAD_cleanup_local(CRYPTO_THREAD_LOCAL *key)
{
*key = OPENSSL_CRYPTO_THREAD_LOCAL_KEY_MAX + 1;
return 1;
}
CRYPTO_THREAD_ID CRYPTO_THREAD_get_current_id(void)
{
return 0;
}
int CRYPTO_THREAD_compare_id(CRYPTO_THREAD_ID a, CRYPTO_THREAD_ID b)
{
return (a == b);
}
int CRYPTO_atomic_add(int *val, int amount, int *ret, CRYPTO_RWLOCK *lock)
{
*val += amount;
*ret = *val;
return 1;
}
int CRYPTO_atomic_or(uint64_t *val, uint64_t op, uint64_t *ret,
CRYPTO_RWLOCK *lock)
{
*val |= op;
*ret = *val;
return 1;
}
int CRYPTO_atomic_load(uint64_t *val, uint64_t *ret, CRYPTO_RWLOCK *lock)
{
*ret = *val;
return 1;
}
int CRYPTO_atomic_store(uint64_t *dst, uint64_t val, CRYPTO_RWLOCK *lock)
{
*dst = val;
return 1;
}
int CRYPTO_atomic_load_int(int *val, int *ret, CRYPTO_RWLOCK *lock)
{
*ret = *val;
return 1;
}
int openssl_init_fork_handlers(void)
{
return 0;
}
int openssl_get_fork_id(void)
{
# if defined(OPENSSL_SYS_UNIX)
return getpid();
# else
return 0;
# endif
}
#endif