Add None provider, path expansion, refactoring

- Add None provider and protocol for solely  creating network-ready
  network namespace with no VPN service

- Add shell path expansion to path arguments (e.g. you can use ~ in
  custom config path)

- Refactor how CLI arguments are parsed using macro_rules

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "vopono"
 description = "Launch applications via VPN tunnels using temporary network namespaces"
-version = "0.10.8"
+version = "0.10.9"
 authors = ["James McMurray <jamesmcm03@gmail.com>"]
 edition = "2021"
 license = "GPL-3.0-or-later"
@@ -31,6 +31,7 @@ config = "0.14"
 basic_tcp_proxy = "0.3.2"
 strum = "0.26"
 strum_macros = "0.26"
+shellexpand = { version = "3", features = ["full"] }
 
 [package.metadata.rpm]
 package = "vopono"

src/args.rs

@@ -114,7 +114,7 @@ pub struct SynchCommand {
 pub struct ExecCommand {
     /// VPN Provider (must be given unless using custom config)
     #[clap(value_enum, long = "provider", short = 'p', ignore_case = true)]
-    pub vpn_provider: Option<WrappedArg<VpnProvider>>,
+    pub provider: Option<WrappedArg<VpnProvider>>,
 
     /// VPN Protocol (if not given will use default)
     #[clap(value_enum, long = "protocol", short = 'c', ignore_case = true)]
@@ -145,15 +145,15 @@ pub struct ExecCommand {
 
     /// Custom VPN Provider - OpenVPN or Wireguard config file (will override other settings)
     #[clap(long = "custom")]
-    pub custom_config: Option<PathBuf>,
+    pub custom: Option<PathBuf>,
 
     /// DNS Server (will override provider's DNS server)
     #[clap(long = "dns", short = 'd')]
     pub dns: Option<Vec<IpAddr>>,
 
     /// List of /etc/hosts entries for the network namespace (e.g. "10.0.1.10 webdav.server01.lan","10.0.1.10 vaultwarden.server01.lan"). For a local host you should also provide the open-hosts option.
     #[clap(long = "hosts", use_value_delimiter = true)]
-    pub hosts_entries: Option<Vec<String>>,
+    pub hosts: Option<Vec<String>>,
 
     /// List of host IP addresses to open on the network namespace (comma separated)
     #[clap(long = "open-hosts", use_value_delimiter = true)]
@@ -174,7 +174,7 @@ pub struct ExecCommand {
 
     /// List of ports to forward from network namespace to host - useful for running servers and daemons
     #[clap(long = "forward", short = 'f')]
-    pub forward_ports: Option<Vec<u16>>,
+    pub forward: Option<Vec<u16>>,
 
     /// Disable proxying to host machine when forwarding ports
     #[clap(long = "no-proxy")]

src/args_config.rs

@@ -0,0 +1,298 @@
+// Handles using the args from either the CLI or config file
+
+use std::{net::IpAddr, path::PathBuf, str::FromStr};
+
+use anyhow::anyhow;
+use config::Config;
+use vopono_core::{
+    config::{providers::VpnProvider, vpn::Protocol},
+    network::{
+        firewall::Firewall,
+        network_interface::{get_active_interfaces, NetworkInterface},
+    },
+    util::{get_config_file_protocol, vopono_dir},
+};
+
+use crate::args::ExecCommand;
+
+macro_rules! command_else_config_option {
+    // Get expression from command - command.expr
+    // If None then read from Config .get("expr")
+    // Returns None if absent in both
+    ($field_id:ident, $command:ident, $config:ident) => {
+        $command.$field_id.clone().or_else(|| {
+            $config
+                .get(stringify!($field_id))
+                .or($config.get(&stringify!($field_id).replace('_', "-")))
+                .map_err(|_e| anyhow!("Failed to read config file"))
+                .ok()
+        })
+    };
+}
+macro_rules! command_else_config_bool {
+    // Get bool ident from command - command.expr
+    // If None then read from Config .get("expr")
+    // Returns false if absent in both
+    ($field_id:ident, $command:ident, $config:ident) => {
+        $command.$field_id
+            || $config
+                .get(stringify!($field_id))
+                .or($config.get(&stringify!($field_id).replace('_', "-")))
+                .map_err(|_e| anyhow!("Failed to read config file"))
+                .ok()
+                .unwrap_or(false)
+    };
+}
+
+macro_rules! command_else_config_option_variant {
+    // Get enum variant ident from command - command.expr
+    // If None then read from Config .get("expr")
+    // Returns None if absent in both
+    ($field_id:ident, $command:ident, $config:ident) => {
+        $command.$field_id.map(|x| x.to_variant()).or_else(|| {
+            $config
+                .get(stringify!($field_id))
+                .or($config.get(&stringify!($field_id).replace('_', "-")))
+                .map_err(|_e| anyhow!("Failed to read config file"))
+                .ok()
+        })
+    };
+}
+
+macro_rules! error_and_bail {
+    // log to error and bail
+    ($msg:literal) => {
+        log::error!("{}", $msg);
+        anyhow::bail!($msg);
+    };
+}
+
+// TODO: Generate this from procedural macro?
+pub struct ArgsConfig {
+    pub provider: VpnProvider,
+    pub protocol: Protocol,
+    pub interface: NetworkInterface,
+    pub server: String,
+    pub application: String,
+    pub user: Option<String>,
+    pub group: Option<String>,
+    pub working_directory: Option<String>,
+    pub custom: Option<PathBuf>,
+    pub dns: Option<Vec<IpAddr>>,
+    pub hosts: Option<Vec<String>>,
+    pub open_hosts: Option<Vec<IpAddr>>,
+    pub no_killswitch: bool,
+    pub keep_alive: bool,
+    pub open_ports: Option<Vec<u16>>,
+    pub forward: Option<Vec<u16>>,
+    pub no_proxy: bool,
+    pub firewall: Firewall,
+    pub disable_ipv6: bool,
+    pub postup: Option<String>,
+    pub predown: Option<String>,
+    pub custom_netns_name: Option<String>,
+    pub allow_host_access: bool,
+    pub port_forwarding: bool,
+    pub custom_port_forwarding: Option<VpnProvider>,
+    pub port_forwarding_callback: Option<String>,
+    pub create_netns_only: bool,
+}
+
+impl ArgsConfig {
+    /// Return new ExecCommand with args from config file if missing in CLI but present there
+    /// Also handle CLI args consistency errors
+    pub fn get_cli_or_config_args(command: ExecCommand, config: Config) -> anyhow::Result<Self> {
+        // TODO: Automate field mapping with procedural macro over ExecCommand struct?
+        let custom: Option<PathBuf> = command_else_config_option!(custom, command, config)
+            .and_then(|p| {
+                shellexpand::full(&p.to_string_lossy())
+                    .ok()
+                    .and_then(|s| PathBuf::from_str(s.as_ref()).ok())
+            });
+        let custom_netns_name = command_else_config_option!(custom_netns_name, command, config);
+        let open_hosts = command_else_config_option!(open_hosts, command, config);
+        let hosts = command_else_config_option!(hosts, command, config);
+        let open_ports = command_else_config_option!(open_ports, command, config);
+        let forward = command_else_config_option!(forward, command, config);
+        let postup = command_else_config_option!(postup, command, config)
+            .and_then(|p| shellexpand::full(&p).ok().map(|s| s.into_owned()));
+
+        let predown = command_else_config_option!(predown, command, config)
+            .and_then(|p| shellexpand::full(&p).ok().map(|s| s.into_owned()));
+        let group = command_else_config_option!(group, command, config);
+        let working_directory = command_else_config_option!(working_directory, command, config)
+            .and_then(|p| shellexpand::full(&p).ok().map(|s| s.into_owned()));
+        let dns = command_else_config_option!(dns, command, config);
+        let user = command_else_config_option!(user, command, config)
+            .or_else(|| std::env::var("SUDO_USER").ok());
+        let port_forwarding_callback =
+            command_else_config_option!(port_forwarding_callback, command, config)
+                .and_then(|p| shellexpand::full(&p).ok().map(|s| s.into_owned()));
+
+        let no_proxy = command_else_config_bool!(no_proxy, command, config);
+        let keep_alive = command_else_config_bool!(keep_alive, command, config);
+        let port_forwarding = command_else_config_bool!(port_forwarding, command, config);
+        let allow_host_access = command_else_config_bool!(allow_host_access, command, config);
+        let create_netns_only = command_else_config_bool!(create_netns_only, command, config);
+        let disable_ipv6 = command_else_config_bool!(disable_ipv6, command, config);
+        let no_killswitch = command_else_config_bool!(no_killswitch, command, config);
+
+        let firewall = command_else_config_option_variant!(firewall, command, config)
+            .ok_or_else(|| anyhow!("Failed to get Firewall variant from args"))
+            .or_else(|_| vopono_core::util::get_firewall())?;
+        let custom_port_forwarding =
+            command_else_config_option_variant!(custom_port_forwarding, command, config);
+
+        if custom_port_forwarding.is_some() && custom.is_none() {
+            log::error!("Custom port forwarding implementation is set, but not using custom provider config file. custom-port-forwarding setting will be ignored");
+        }
+
+        // Assign network interface from args or vopono config file
+        // TODO: Does this work with string from config file?
+        let interface = command_else_config_option!(interface, command, config);
+
+        let interface: NetworkInterface = match interface {
+            Some(x) => anyhow::Result::<NetworkInterface>::Ok(x),
+            None => {
+                let active_interfaces = get_active_interfaces()?;
+                if active_interfaces.len() > 1 {
+                    log::warn!("Multiple network interfaces are active: {:#?}, consider specifying the interface with the -i argument. Using {}", &active_interfaces, &active_interfaces[0]);
+                }
+                Ok(
+            NetworkInterface::new(
+            active_interfaces
+                .into_iter()
+                .next()
+                .ok_or_else(|| anyhow!("No active network interface - consider overriding network interface selection with -i argument"))?,
+        )?)
+            }
+        }?;
+        log::debug!("Interface: {}", &interface.name);
+
+        let provider: VpnProvider;
+        let server: String;
+        let protocol: Protocol;
+
+        // Assign protocol and server from args or vopono config file or custom config if used
+        if let Some(path) = &custom {
+            protocol = command
+                .protocol
+                .map(|x| x.to_variant())
+                .ok_or_else(|| anyhow!("."))
+                .or_else(|_| get_config_file_protocol(path))?;
+
+            provider = VpnProvider::Custom;
+
+            if protocol != Protocol::OpenConnect {
+                // Encode filename with base58 so we can fit it within 16 chars for the veth pair name
+                let sname = bs58::encode(&path.to_str().unwrap()).into_string();
+
+                server = sname[0..std::cmp::min(11, sname.len())].to_string();
+            } else {
+                // For OpenConnect the server-name can be provided via the usual config or
+                // command-line-options. Since it also can be provided via the custom-config we will
+                // set an empty-string if it isn't provided.
+                server = command_else_config_option!(server, command, config).unwrap_or_default();
+            }
+        } else {
+            // Get server and provider
+            provider = command_else_config_option_variant!(provider, command, config).ok_or_else(
+                || {
+                    let msg =
+                "Enter a VPN provider as a command-line argument or in the vopono config.toml file";
+                    log::error!("{}", msg);
+                    anyhow!(msg)
+                },
+            )?;
+
+            if provider == VpnProvider::Custom {
+                error_and_bail!("Must provide config file if using custom VPN Provider");
+            }
+
+            server = command_else_config_option!(server, command, config)
+        // Work-around for providers which do not need a server - TODO: Clean this
+         .or_else(|| if provider == VpnProvider::Warp {Some("warp".to_owned())} else {None})
+         .or_else(|| if provider == VpnProvider::None {Some("none".to_owned())} else {None})
+            .ok_or_else(|| {
+                let msg = "VPN server prefix must be provided as a command-line argument or in the vopono config.toml file";
+                log::error!("{}", msg); anyhow!(msg)})?;
+
+            // Check protocol is valid for provider
+            protocol = command_else_config_option_variant!(protocol, command, config)
+                .unwrap_or_else(|| provider.get_dyn_provider().default_protocol());
+        }
+
+        if (provider == VpnProvider::Warp && protocol != Protocol::Warp)
+            || (provider != VpnProvider::Warp && protocol == Protocol::Warp)
+        {
+            error_and_bail!("Cloudflare Warp protocol must use Warp provider");
+        }
+
+        if provider == VpnProvider::None && custom.is_some() {
+            error_and_bail!("Custom config cannot be set when using None provider");
+        }
+
+        if (provider == VpnProvider::None && protocol != Protocol::None)
+            || (provider != VpnProvider::None && protocol == Protocol::None)
+        {
+            error_and_bail!("None protocol must use None provider - will run not run any VPN service inside netns");
+        }
+
+        Ok(Self {
+            provider,
+            protocol,
+            interface,
+            server,
+            // TODO: Allow application to be saved in config file? - breaking change to CLI interface
+            application: command.application,
+            user,
+            group,
+            working_directory,
+            custom,
+            dns,
+            hosts,
+            open_hosts,
+            no_killswitch,
+            keep_alive,
+            open_ports,
+            forward,
+            no_proxy,
+            firewall,
+            disable_ipv6,
+            postup,
+            predown,
+            custom_netns_name,
+            allow_host_access,
+            port_forwarding,
+            custom_port_forwarding,
+            port_forwarding_callback,
+            create_netns_only,
+        })
+    }
+
+    /// Read vopono config file to Config struct
+    pub fn get_config_file(command: &ExecCommand) -> anyhow::Result<Config> {
+        let config_path = command
+            .vopono_config
+            .clone()
+            .ok_or_else(|| anyhow!("No config file passed"))
+            .or_else::<anyhow::Error, _>(|_| Ok(vopono_dir()?.join("config.toml")))?;
+        {
+            std::fs::OpenOptions::new()
+                .write(true)
+                .create(true)
+                .truncate(false)
+                .read(true)
+                .open(&config_path)?;
+        }
+        let vopono_config_settings_builder =
+            config::Config::builder().add_source(config::File::from(config_path.clone()));
+        vopono_config_settings_builder.build().map_err(|e| {
+            anyhow!(
+                "Failed to parse config from: {} , err: {}",
+                config_path.to_string_lossy(),
+                e
+            )
+        })
+    }
+}