TCP input TLS - Add SslBio, wrapper around BIO.

Author: BonnyAD9

src/plugins/input/tcp/src/tls/SslBio.hpp

@@ -0,0 +1,65 @@
+/**
+ * \file
+ * \author Jakub Antonín Štigler <[email protected]>
+ * \brief Wrapper around BIO from OpenSSL. (header file)
+ * \date 2025
+ *
+ * Copyright: (C) 2023 CESNET, z.s.p.o.
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#pragma once
+
+#include <memory>
+
+#include <openssl/bio.h>
+
+#include "../UniqueFd.hpp"
+#include "throw_ssl_err.hpp"
+
+namespace tcp_in {
+namespace tls {
+
+/**
+ * @brief Wrapper around `BIO` from OpenSSL.
+ *
+ * This is basically extension of file descriptor used in OpenSSL.
+ */
+class SslBio {
+public:
+    /**
+     * @brief Constructs new `SslBio` for the given `BIO_METHOD`.
+     * @param method Method created for example by `BIO_s_socket()`.
+     * @throws `std::runtime_error` on failure.
+     */
+    SslBio(const BIO_METHOD *method) : m_bio(BIO_new(method)) {
+        if (!m_bio.get()) {
+            throw_ssl_err("Failed to create bio.");
+        }
+    }
+
+    /**
+     * @brief Set file descriptor of the bio.
+     * @param fd File descriptor for the bio. This will NOT take ownership of the file descriptor.
+     */
+    void set_fd(int fd) noexcept { BIO_set_fd(m_bio.get(), fd, BIO_NOCLOSE); }
+
+    /**
+     * @brief Gets the pointer to bio and releases ownership of it.
+     * @return Pointer to the inner bio.
+     */
+    BIO *release_ptr() noexcept { return m_bio.release(); }
+
+private:
+    /** Deleter for BIO. */
+    class Deleter {
+    public:
+        void operator()(BIO *bio) { BIO_free(bio); }
+    };
+
+    std::unique_ptr<BIO, Deleter> m_bio;
+};
+
+
+} // namespace tls
+} // namespace tcp_in