// rand_state_get pops a |rand_state| from the head of
// |rand_state_free_list| and returns it. If the list is empty, it
// creates a fresh |rand_state| and returns that instead.
static struct rand_state *rand_state_get(void) {
struct rand_state *state = NULL;
CRYPTO_STATIC_MUTEX_lock_write(rand_state_lock_bss_get());
state = *rand_state_free_list_bss_get();
if (state != NULL) {
*rand_state_free_list_bss_get() = state->next;
}
CRYPTO_STATIC_MUTEX_unlock_write(rand_state_lock_bss_get());
if (state != NULL) {
return state;
}
state = OPENSSL_malloc(sizeof(struct rand_state));
if (state == NULL) {
return NULL;
}
rand_state_init(state);
#if defined(BORINGSSL_FIPS)
CRYPTO_STATIC_MUTEX_lock_write(rand_state_lock_bss_get());
state->next_all = *rand_state_all_list_bss_get();
*rand_state_all_list_bss_get() = state;
CRYPTO_STATIC_MUTEX_unlock_write(rand_state_lock_bss_get());
#endif
return state;
}
void RAND_enable_fork_unsafe_buffering(int fd) {
if (fd >= 0) {
fd = dup(fd);
if (fd < 0) {
abort();
}
} else {
fd = kUnset;
}
CRYPTO_STATIC_MUTEX_lock_write(&requested_lock);
urandom_buffering_requested = 1;
urandom_fd_requested = fd;
CRYPTO_STATIC_MUTEX_unlock_write(&requested_lock);
CRYPTO_once(&once, init_once);
if (urandom_buffering != 1) {
abort(); // Already initialized
}
if (fd >= 0) {
if (urandom_fd == kHaveGetrandom) {
close(fd);
} else if (urandom_fd != fd) {
abort(); // Already initialized.
}
}
}
void RAND_set_urandom_fd(int fd) {
fd = dup(fd);
if (fd < 0) {
abort();
}
CRYPTO_STATIC_MUTEX_lock_write(&requested_lock);
urandom_fd_requested = fd;
CRYPTO_STATIC_MUTEX_unlock_write(&requested_lock);
CRYPTO_once(&once, init_once);
if (urandom_fd == kHaveGetrandom) {
close(fd);
} else if (urandom_fd != fd) {
abort(); // Already initialized.
}
}
// rand_state_put pushes |state| onto |rand_state_free_list|.
static void rand_state_put(struct rand_state *state) {
CRYPTO_STATIC_MUTEX_lock_write(rand_state_lock_bss_get());
state->next = *rand_state_free_list_bss_get();
*rand_state_free_list_bss_get() = state;
CRYPTO_STATIC_MUTEX_unlock_write(rand_state_lock_bss_get());
}
