fix: ensure known_hosts is up to date

Cargo.lock

@@ -974,7 +974,7 @@ dependencies = [
  "hashbrown 0.14.0",
  "lock_api",
  "once_cell",
- "parking_lot_core",
+ "parking_lot_core 0.9.8",
 ]
 
 [[package]]
@@ -1805,6 +1805,7 @@ dependencies = [
  "similar",
  "slug",
  "ssh-key",
+ "ssh2",
  "tauri",
  "tauri-build",
  "tauri-plugin-context-menu",
@@ -1911,7 +1912,7 @@ dependencies = [
  "futures-timer",
  "no-std-compat",
  "nonzero_ext",
- "parking_lot",
+ "parking_lot 0.12.1",
  "quanta",
  "rand 0.8.5",
  "smallvec",
@@ -2975,7 +2976,7 @@ dependencies = [
  "file-id",
  "log",
  "notify",
- "parking_lot",
+ "parking_lot 0.12.1",
  "walkdir",
 ]
 
@@ -3293,6 +3294,17 @@ version = "2.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bb813b8af86854136c6922af0598d719255ecb2179515e6e7730d468f05c9cae"
 
+[[package]]
+name = "parking_lot"
+version = "0.11.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7d17b78036a60663b797adeaee46f5c9dfebb86948d1255007a1d6be0271ff99"
+dependencies = [
+ "instant",
+ "lock_api",
+ "parking_lot_core 0.8.6",
+]
+
 [[package]]
 name = "parking_lot"
 version = "0.12.1"
@@ -3300,7 +3312,21 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3742b2c103b9f06bc9fff0a37ff4912935851bee6d36f3c02bcc755bcfec228f"
 dependencies = [
  "lock_api",
- "parking_lot_core",
+ "parking_lot_core 0.9.8",
+]
+
+[[package]]
+name = "parking_lot_core"
+version = "0.8.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "60a2cfe6f0ad2bfc16aefa463b497d5c7a5ecd44a23efa72aa342d90177356dc"
+dependencies = [
+ "cfg-if",
+ "instant",
+ "libc",
+ "redox_syscall 0.2.16",
+ "smallvec",
+ "winapi",
 ]
 
 [[package]]
@@ -3749,7 +3775,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "51de85fb3fb6524929c8a2eb85e6b6d363de4e8c48f9e2c2eac4944abc181c93"
 dependencies = [
  "log",
- "parking_lot",
+ "parking_lot 0.12.1",
  "scheduled-thread-pool",
 ]
 
@@ -4214,7 +4240,7 @@ version = "0.2.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3cbc66816425a074528352f5789333ecff06ca41b36b0b0efdfbb29edc391a19"
 dependencies = [
- "parking_lot",
+ "parking_lot 0.12.1",
 ]
 
 [[package]]
@@ -4767,6 +4793,18 @@ dependencies = [
  "zeroize",
 ]
 
+[[package]]
+name = "ssh2"
+version = "0.9.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e7fe461910559f6d5604c3731d00d2aafc4a83d1665922e280f42f9a168d5455"
+dependencies = [
+ "bitflags 1.3.2",
+ "libc",
+ "libssh2-sys",
+ "parking_lot 0.11.2",
+]
+
 [[package]]
 name = "stable_deref_trait"
 version = "1.2.0"
@@ -4796,7 +4834,7 @@ checksum = "f91138e76242f575eb1d3b38b4f1362f10d3a43f47d182a5b359af488a02293b"
 dependencies = [
  "new_debug_unreachable",
  "once_cell",
- "parking_lot",
+ "parking_lot 0.12.1",
  "phf_shared 0.10.0",
  "precomputed-hash",
  "serde",
@@ -4937,7 +4975,7 @@ dependencies = [
  "ndk-sys",
  "objc",
  "once_cell",
- "parking_lot",
+ "parking_lot 0.12.1",
  "png",
  "raw-window-handle",
  "scopeguard",
@@ -5335,7 +5373,7 @@ dependencies = [
  "libc",
  "mio",
  "num_cpus",
- "parking_lot",
+ "parking_lot 0.12.1",
  "pin-project-lite",
  "signal-hook-registry",
  "socket2 0.5.5",

packages/tauri/Cargo.toml

@@ -58,6 +58,7 @@ sha2 = "0.10.8"
 similar = { version = "2.2.1", features = ["unicode"] }
 slug = "0.1.5"
 ssh-key = { version = "0.6.3", features = [ "alloc", "ed25519" ] }
+ssh2 = { version = "0.9.4", features = ["vendored-openssl"] }
 tauri = { version = "1.5.2", features = ["dialog-open", "fs-read-file", "path-all", "process-relaunch", "protocol-asset", "shell-open", "system-tray", "window-maximize", "window-start-dragging", "window-unmaximize"] }
 tauri-plugin-context-menu = { git = "https://github.com/gitbutlerapp/tauri-plugin-context-menu", branch = "main" }
 tauri-plugin-single-instance = { git = "https://github.com/tauri-apps/plugins-workspace", branch = "v1" }

packages/tauri/src/git/url.rs

@@ -18,7 +18,7 @@ pub struct Url {
     /// The password associated with a user.
     password: Option<String>,
     /// The host to which to connect. Localhost is implied if `None`.
-    host: Option<String>,
+    pub host: Option<String>,
     /// When serializing, use the alternative forms as it was parsed as such.
     serialize_alternative_form: bool,
     /// The port to use when connecting to a host. If `None`, standard ports depending on `scheme` will be used.

packages/tauri/src/lib.rs

@@ -22,6 +22,7 @@ pub mod projects;
 pub mod reader;
 pub mod sentry;
 pub mod sessions;
+pub mod ssh;
 pub mod storage;
 pub mod users;
 pub mod virtual_branches;

packages/tauri/src/project_repository/repository.rs

@@ -7,7 +7,7 @@ use anyhow::{Context, Result};
 
 use crate::{
     git::{self, credentials::HelpError, Url},
-    keys, projects, reader, users,
+    keys, projects, reader, ssh, users,
     virtual_branches::Branch,
 };
 
@@ -352,6 +352,9 @@ impl Repository {
 
         let auth_flows = credentials.help(self, branch.remote())?;
         for (mut remote, callbacks) in auth_flows {
+            if let Some(url) = remote.url().context("failed to get remote url")? {
+                ssh::check_known_host(&url).context("failed to check known host")?;
+            }
             for callback in callbacks {
                 match remote.push(
                     &[refspec.as_str()],
@@ -391,6 +394,9 @@ impl Repository {
         let refspec = &format!("+refs/heads/*:refs/remotes/{}/*", remote_name);
         let auth_flows = credentials.help(self, remote_name)?;
         for (mut remote, callbacks) in auth_flows {
+            if let Some(url) = remote.url().context("failed to get remote url")? {
+                ssh::check_known_host(&url).context("failed to check known host")?;
+            }
             for callback in callbacks {
                 let mut fetch_opts = git2::FetchOptions::new();
                 fetch_opts.remote_callbacks(callback.into());

packages/tauri/src/ssh.rs

@@ -0,0 +1,63 @@
+use std::{env, fs, path::Path};
+
+use ssh2::{self, CheckResult, KnownHostFileKind};
+
+use crate::git;
+
+#[derive(Debug, thiserror::Error)]
+pub enum Error {
+    #[error(transparent)]
+    Ssh(ssh2::Error),
+    #[error(transparent)]
+    Io(std::io::Error),
+    #[error("mismatched host key")]
+    MismatchedHostKey,
+    #[error("failed to check the known hosts")]
+    Failure,
+}
+
+pub fn check_known_host(remote_url: &git::Url) -> Result<(), Error> {
+    let host = if let Some(host) = remote_url.host.as_ref() {
+        host
+    } else {
+        return Ok(());
+    };
+
+    let mut session = ssh2::Session::new().map_err(Error::Ssh)?;
+    session
+        .set_tcp_stream(std::net::TcpStream::connect(format!("{}:22", host)).map_err(Error::Io)?);
+    session.handshake().map_err(Error::Ssh)?;
+
+    let mut known_hosts = session.known_hosts().map_err(Error::Ssh)?;
+
+    // Initialize the known hosts with a global known hosts file
+    let dotssh = Path::new(&env::var("HOME").unwrap()).join(".ssh");
+    let file = dotssh.join("known_hosts");
+    if !file.exists() {
+        fs::create_dir_all(&dotssh).map_err(Error::Io)?;
+        fs::File::create(&file).map_err(Error::Io)?;
+    }
+
+    known_hosts
+        .read_file(&file, KnownHostFileKind::OpenSSH)
+        .map_err(Error::Ssh)?;
+
+    // Now check to see if the seesion's host key is anywhere in the known
+    // hosts file
+    let (key, key_type) = session.host_key().unwrap();
+    match known_hosts.check(host, key) {
+        CheckResult::Match => Ok(()),
+        CheckResult::Mismatch => Err(Error::MismatchedHostKey),
+        CheckResult::Failure => Err(Error::Failure),
+        CheckResult::NotFound => {
+            tracing::info!("adding host key for {}", host);
+            known_hosts
+                .add(host, key, "added by gitbutler client", key_type.into())
+                .map_err(Error::Ssh)?;
+            known_hosts
+                .write_file(&file, KnownHostFileKind::OpenSSH)
+                .map_err(Error::Ssh)?;
+            Ok(())
+        }
+    }
+}