TCP input TLS - Add SslBio, wrapper around BIO.

Author: BonnyAD9

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

@@ -0,0 +1,76 @@
+/**
+ * \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 {
+
+namespace dealloc {
+
+/** Deleter for `BIO` from OpenSSL. Can be used for example in `std::unique_ptr` */
+class SslBio {
+public:
+    void operator()(BIO *bio) { BIO_free(bio); }
+};
+
+}
+
+/**
+ * @brief Wrapper around `BIO` from OpenSSL.
+ *
+ * This is basically extension of file descriptor used in OpenSSL.
+ */
+class SslBio : public std::unique_ptr<BIO, dealloc::SslBio> {
+public:
+    /** Unique pointer of `BIO`. This is base class for `SslBio`. */
+    using SelfPtr = std::unique_ptr<BIO, dealloc::SslBio>;
+
+    /**
+     * @brief Construct `SslBio` by taking ownership of the given `BIO`.
+     * @param bio Underlaying `BIO`. This will take ownership of it.
+     * @throws If `bio` is `nullptr`.
+     */
+    SslBio(BIO *bio) : SelfPtr(bio) {
+        if (!get()) {
+            throw_ssl_err("Failed to create bio.");
+        }
+    }
+
+    /**
+     * @brief Constructs new `SslBio` for the given `BIO_METHOD`.
+     * @param method Method created for example by `BIO_s_socket()`.
+     * @throws On failure.
+     */
+    SslBio(const BIO_METHOD *method) : SslBio(BIO_new(method)) { }
+    /**
+     * @brief Construct `SslBio` server listening at the given port (and address).
+     * @param host_port Port and optionally also address of the server. `[address:]port`.
+     * @throws On failure.
+     */
+    SslBio(const char *host_port) : SslBio(BIO_new_accept(host_port)) { }
+
+    /**
+     * @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(get(), fd, BIO_NOCLOSE); }
+};
+
+
+} // namespace tls
+} // namespace tcp_in