Rename project wg2sd -> wg2nd, new CLI + generate

1. Renamed the project from wg2sd to wg2nd
2. Modified the _gen_netdev_cfg() function to handle the MTUBytes field.
3. Add new CLI with `generate` and `install` commands
4. Modified the gen_systemd_config() function to accept keyfile_or_output_path and filename parameters.
   - user can choose the name of the keyfile on the CLI
   - user can choose alternative output filename (instead of just using
     the  interface name)

1 files changed, 147 insertions, 0 deletions

diff --git a/src/wg2nd.hpp b/src/wg2nd.hpp
new file mode 100644
index 0000000..7bf7f54
--- /dev/null
+++ b/src/wg2nd.hpp
@@ -0,0 +1,147 @@
+#pragma once
+
+#include <istream>
+#include <exception>
+#include <optional>
+#include <string>
+#include <vector>
+#include <filesystem>
+
+#include <cstdint>
+
+namespace wg2nd {
+
+	struct Interface {
+		// File name, or defaults to "wg"
+		std::string name;
+		// Address=...
+		// List of ip addresses to be assigned to the interface
+		std::vector<std::string> addresses;
+		// PrivateKey=...
+		// Base64-encoded private key string
+		std::string private_key;
+		// MTu=..
+		std::string mtu;
+		// DNS=...
+		// DNS consists of a comma-separated list of IP addresses of DNS servers
+		std::vector<std::string> DNS;
+		// Table=...
+		// By default, wireguard creates routes. This is disabled, when Table=off
+		bool should_create_routes;
+		// Table number (if specific), 0 if auto
+		uint32_t table;
+		// ListenPort=...
+		// The port number on which the interface will listen
+		std::optional<uint16_t> listen_port;
+		// PreUp, PostUp, PreDown PostDown
+		std::string preup, postup, predown, postdown;
+		// SaveConfig
+		std::string save_config;
+
+		Interface()
+			: should_create_routes { false }
+			, table { 0 }
+			, listen_port { }
+		{ }
+	};
+
+	struct Cidr {
+		std::string route;
+		bool is_default_route;
+		bool is_ipv4;
+	};
+
+	struct Peer {
+		// Endpoint=...
+		// IP and port of the peer
+		std::string endpoint;
+		// PublicKey=...
+		std::string public_key;
+		// AllowedIPs=...
+		// Comma separated list of allowed ips
+		// Each allowed ip is a CIDR block
+		std::vector<Cidr> allowed_ips;
+		// PersistentAlive=...
+		std::string persistent_keepalive;
+		// PresharedKey=...
+		std::string preshared_key;
+	};
+
+	struct Config {
+		// [Interface]
+		Interface intf;
+		// [Peer]
+		std::vector<Peer> peers;
+		// If one of the peers has a default route
+		bool has_default_route;
+
+		Config()
+			: has_default_route { false }
+		{ }
+	};
+
+	class ConfigurationException : public std::exception {
+
+		public:
+
+			ConfigurationException(std::string const & message)
+				: _message { message }
+			{}
+
+			char const * what() const noexcept override {
+				return _message.c_str();
+			}
+
+		private:
+			std::string _message;
+	};
+
+	class ParsingException : public ConfigurationException {
+
+		public:
+
+			ParsingException(std::string const & message, std::optional<uint64_t> line_no = {})
+				: ConfigurationException(message)
+				, _line_no { line_no }
+			{}
+
+
+			std::optional<uint64_t> line_no() const noexcept {
+				return _line_no;
+			}
+
+		private:
+			std::string _message;
+			std::optional<uint64_t> _line_no;
+	};
+
+	struct SystemdFilespec {
+		std::string name;
+		std::string contents;
+	};
+
+	struct SystemdConfig {
+		SystemdFilespec netdev;
+		SystemdFilespec network;
+		SystemdFilespec private_keyfile;
+		std::vector<SystemdFilespec> symmetric_keyfiles;
+
+		std::vector<std::string> warnings;
+		std::string firewall;
+	};
+
+	std::string interface_name_from_filename(std::filesystem::path config_path);
+
+	Config parse_config(std::string const & interface_name, std::istream & stream);
+
+	SystemdConfig gen_systemd_config(
+		Config const & cfg,
+		std::filesystem::path const & keyfile_or_output_path,
+		std::optional<std::string> const & filename
+	);
+
+	SystemdConfig wg2nd(std::string const & interface_name, std::istream & stream,
+		std::filesystem::path const & keyfile_or_output_path,
+		std::optional<std::string> const & filename);
+
+};