c - OpenSSL 线程安全吗？

Question

如果我在一个线程中执行 SSL 握手并在单独的线程中执行 SSL_read 和 SSL_write，是否会有问题？

Answer 1

是

OpenSSL threads manual

OpenSSL can safely be used in multi-threaded applications provided that at least two callback functions are set, locking_function and threadid_func.

Recommended library setup sample

void thread_setup(void)
{
    int i;

    lock_cs = OPENSSL_malloc(CRYPTO_num_locks() * sizeof(HANDLE));
    for (i = 0; i < CRYPTO_num_locks(); i++) {
        lock_cs[i] = CreateMutex(NULL, FALSE, NULL);
    }

    CRYPTO_set_locking_callback((void (*)(int, int, char *, int))
                                win32_locking_callback);
    /* id callback defined */
}

void thread_cleanup(void)
{
    int i;

    CRYPTO_set_locking_callback(NULL);
    for (i = 0; i < CRYPTO_num_locks(); i++)
        CloseHandle(lock_cs[i]);
    OPENSSL_free(lock_cs);
}