nerve-ipc-core 0.1.1

Core IPC layer for the NERVE protocol: authentication, request lifecycle, transport-agnostic dispatch, Unix Domain Socket server, and WebSocket server.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90

//! Runtime configuration for nerve-ipc-core.
//!
//! [`Config`] controls the WebSocket bind address and port, the expected
//! browser extension ID for Origin checking, the token storage path, and the
//! Unix Domain Socket path.
//!
//! [`Config::default`] provides production-safe defaults:
//!
//! | Field | Default |
//! |---|---|
//! | `bind_addr` | `127.0.0.1` |
//! | `ws_port` | `9001` |
//! | `allowed_extension_id` | `""` (origin checking disabled) |
//! | `token_path` | `~/.anvesha/token` |
//! | `uds_path` | `/tmp/nerve.sock` |
//!
//! # Security note
//!
//! `bind_addr` must always be `127.0.0.1`. Setting it to `0.0.0.0` would
//! expose the daemon to the local network, which violates the local-first
//! security model.

use std::net::Ipv4Addr;
use std::path::PathBuf;

/// Runtime configuration for nerve-ipc-core.
///
/// The bind address is always `127.0.0.1` — exposing the daemon on `0.0.0.0`
/// would make it reachable from the LAN, which is a security violation for a
/// local-first system.
///
/// # Examples
///
/// ```
/// use nerve_ipc_core::Config;
///
/// // Default configuration: origin checking disabled (empty extension ID).
/// let config = Config::default();
/// assert_eq!(config.allowed_origin(), None);
///
/// // Production: enforce origin checking against a specific extension ID.
/// let config = Config {
///     allowed_extension_id: "abcdefghijklmnopqrstuvwxyzabcdef".to_string(),
///     ..Config::default()
/// };
/// assert_eq!(
///     config.allowed_origin(),
///     Some("chrome-extension://abcdefghijklmnopqrstuvwxyzabcdef".to_string()),
/// );
/// ```
#[derive(Clone)]
pub struct Config {
    /// WebSocket bind address. MUST be 127.0.0.1. Never 0.0.0.0.
    pub bind_addr: Ipv4Addr,
    /// WebSocket port.
    pub ws_port: u16,
    /// Chrome extension ID allowed to connect.
    /// Derives the expected `Origin: chrome-extension://<id>` header.
    /// Empty string disables origin checking (test mode only).
    pub allowed_extension_id: String,
    /// Path where the per-install auth token is stored.
    pub token_path: PathBuf,
    /// Unix Domain Socket path for the UDS server.
    pub uds_path: String,
}

impl Config {
    /// Return the expected `Origin` header value for the allowed extension,
    /// or `None` when origin checking is disabled (empty extension ID).
    pub fn allowed_origin(&self) -> Option<String> {
        if self.allowed_extension_id.is_empty() {
            None
        } else {
            Some(format!("chrome-extension://{}", self.allowed_extension_id))
        }
    }
}

impl Default for Config {
    fn default() -> Self {
        let home = std::env::var("HOME").unwrap_or_else(|_| "/tmp".to_string());
        Self {
            bind_addr: Ipv4Addr::LOCALHOST,
            ws_port: 9001,
            allowed_extension_id: String::new(),
            token_path: PathBuf::from(home).join(".anvesha").join("token"),
            uds_path: "/tmp/nerve.sock".to_string(),
        }
    }
}