╭ serve_ssh.zig ────────────────────────────────────────────────╮ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ ╰───────────────────────────────────────────────────────────────╯
🬐 🬠 🬞🬂🬏 🬟 🬑 🬟 🬑 ╭f9d09c76..╮ f9d09c76.. see-em: 🬋🬋🬋 🬋🬋🬋 🬋 🬋 │files │ commits refs discuss issues new login 🬐 🬠 🬐 🬠 🬑 🬟 🬰 ╰──────────╯ (632) user
╭────╮ ╭ clone ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ╮ │http│ ssh │ │ ╰────╯ ╰ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ╯
.. embed/ event/ test/ ui/ command.zig diff3.zig event.zig find.zig fork.zig lib.zig main.zig main_wasm.zig markdown.zig patch.zig progress.zig push.zig search.zig search_commit.zig search_thread.zig serve.zig serve_common.zig serve_http.zig ╭─────────────────────────────────╮ │serve_ssh.zig │ ╰─────────────────────────────────╯ serve_ssh_protocol.zig test.zig testnet.zig try.zig ui.zig web.zig
1 const std = @import("std"); 2 const push = @import("push.zig"); 3 const xit = @import("xit"); 4 const rp = xit.repo; 5 const xitui = xit.xitui; 6 const StreamTerminal = xitui.stream_terminal.StreamTerminal; 7 const Size = xitui.layout.Size; 8 const ui = @import("./ui.zig"); 9 const ssh = @import("./serve_ssh_protocol.zig"); 10 const evt = @import("./event.zig"); 11 const serve_common = @import("./serve_common.zig"); 12 const fork = @import("./fork.zig"); 13 const progress = @import("./progress.zig"); 14 15 // listener resource limits. the watchdog gives peers a hard deadline to start 16 // a session, times out non-interactive sessions that stall while we're blocked 17 // on the peer, and bounds the post-CLOSE drain. 18 const max_connections: u32 = 4096; 19 const watchdog_interval = std.Io.Duration.fromSeconds(5); 20 const presession_timeout_ticks: u32 = 6; // 30 seconds 21 const idle_timeout_ticks: u32 = 24; // 120 seconds 22 const close_drain_timeout_ticks: u32 = 2; // 5-10 seconds 23 const escape_timeout: std.Io.Timeout = .{ .duration = .{ .raw = .fromMilliseconds(25), .clock = .awake } }; 24 25 var active_connections: std.atomic.Value(u32) = .init(0); 26 27 const any_repo_opts: rp.AnyRepoOpts(.xit) = .{ .ProgressCtx = *progress.Sideband }; 28 29 pub const SessionHandler = struct { 30 admin_repo_path: []const u8, 31 users_dir: []const u8, 32 wui_port: u16, // port the web UI is served on, shown in the TUI footer's url 33 git_http_port: ?u16, 34 git_ssh_port: ?u16, 35 git_ssh_prefix: []const u8, 36 err: *std.Io.Writer, 37 38 /// returning without an exit leaves the protocol layer to send status 0 39 pub fn handleSession(self: *const SessionHandler, sess: *ssh.SessionCtx, request: ssh.Request) !void { 40 serve_common.logError(sess.conn.io, self.err, "ssh session: kind={s} key={s}\n", .{ @tagName(request), sess.fingerprint }); 41 switch (request) { 42 .shell => |pty_maybe| { 43 const pty = pty_maybe orelse { 44 // a shell without a pty has no useful TUI to render; in 45 // openssh client terms this is `ssh -T host`. say so and 46 // exit non-zero. 47 try sess.writeBytes("haxy ssh: this server only serves the TUI when a pty is allocated (use a normal `ssh` invocation).\r\n"); 48 try sess.exit(1); 49 return; 50 }; 51 sess.exemptFromIdleTimeout(); 52 try runTuiSession(self, sess, pty); 53 }, 54 .exec => |exec| { 55 try runGitSession(self, sess, exec); 56 }, 57 } 58 } 59 }; 60 61 pub fn runListener( 62 io: std.Io, 63 allocator: std.mem.Allocator, 64 host_key: *const ssh.HostKey, 65 session_handler: *const SessionHandler, 66 watchdog: *Watchdog, 67 net_server: *std.Io.net.Server, 68 tasks: *std.Io.Group, 69 err: *std.Io.Writer, 70 ) void { 71 const Context = struct { 72 io: std.Io, 73 allocator: std.mem.Allocator, 74 host_key: *const ssh.HostKey, 75 session_handler: *const SessionHandler, 76 watchdog: *Watchdog, 77 err: *std.Io.Writer, 78 }; 79 80 const handle = struct { 81 fn h(ctx: Context, stream: std.Io.net.Stream) void { 82 defer stream.close(ctx.io); 83 84 const prev_count = active_connections.fetchAdd(1, .acq_rel); 85 defer _ = active_connections.fetchSub(1, .acq_rel); 86 if (prev_count >= max_connections) { 87 serve_common.logError(ctx.io, ctx.err, "ssh: connection limit reached, dropping\n", .{}); 88 return; 89 } 90 91 var connection = Watchdog.Connection{ .stream = &stream }; 92 ctx.watchdog.add(ctx.io, &connection); 93 defer ctx.watchdog.remove(ctx.io, &connection); 94 95 // timed peeks need room for a complete encrypted packet 96 var recv_buf: [ssh.packet_buffer_size]u8 = undefined; 97 var send_buf: [4096]u8 = undefined; 98 var stream_reader = stream.reader(ctx.io, &recv_buf); 99 var stream_writer = stream.writer(ctx.io, &send_buf); 100 ssh.handleConnection( 101 ctx.io, 102 ctx.allocator, 103 &stream_reader.interface, 104 &stream_writer.interface, 105 ctx.host_key, 106 &connection.idle_state, 107 ctx.session_handler, 108 ) catch |session_err| { 109 serve_common.logError(ctx.io, ctx.err, "ssh session failed: {s}\n", .{@errorName(session_err)}); 110 }; 111 } 112 }.h; 113 114 // without the watchdog nothing bounds a connection, so don't listen 115 tasks.concurrent(io, Watchdog.run, .{ watchdog, io }) catch |spawn_err| { 116 serve_common.logError(io, err, "ssh: watchdog spawn failed: {s}\n", .{@errorName(spawn_err)}); 117 return; 118 }; 119 120 serve_common.runListener(io, net_server, tasks, err, "ssh", Context{ 121 .io = io, 122 .allocator = allocator, 123 .host_key = host_key, 124 .session_handler = session_handler, 125 .watchdog = watchdog, 126 .err = err, 127 }, handle); 128 } 129 130 /// one task watches every connection. a connection links its entry only 131 /// while it runs, so the watchdog never sees a closed stream. 132 pub const Watchdog = struct { 133 mutex: std.Io.Mutex = .init, 134 connections: std.DoublyLinkedList = .{}, 135 136 const Connection = struct { 137 node: std.DoublyLinkedList.Node = .{}, 138 stream: *const std.Io.net.Stream, 139 idle_state: ssh.IdleState = .{}, 140 // tick state, touched only by the watchdog 141 last_seen: u64 = 0, 142 presession_ticks: u32 = 0, 143 idle_ticks: u32 = 0, 144 closing_ticks: u32 = 0, 145 146 // interactive sessions are exempt only from the idle timeout, so a 147 // stalled teardown can still be broken 148 fn timedOut(self: *Connection) bool { 149 if (self.idle_state.closing.load(.acquire)) { 150 self.closing_ticks += 1; 151 return self.closing_ticks >= close_drain_timeout_ticks; 152 } 153 if (!self.idle_state.session_started.load(.acquire)) { 154 self.presession_ticks += 1; 155 return self.presession_ticks >= presession_timeout_ticks; 156 } 157 if (self.idle_state.exempt.load(.acquire)) return false; 158 159 // our own work between packets is not the peer idling 160 const seen = self.idle_state.activity.load(.acquire); 161 defer self.last_seen = seen; 162 if (self.idle_state.waiting.load(.acquire) and seen == self.last_seen) { 163 self.idle_ticks += 1; 164 } else { 165 self.idle_ticks = 0; 166 } 167 return self.idle_ticks >= idle_timeout_ticks; 168 } 169 }; 170 171 fn add(self: *Watchdog, io: std.Io, connection: *Connection) void { 172 self.mutex.lockUncancelable(io); 173 defer self.mutex.unlock(io); 174 self.connections.append(&connection.node); 175 } 176 177 fn remove(self: *Watchdog, io: std.Io, connection: *Connection) void { 178 self.mutex.lockUncancelable(io); 179 defer self.mutex.unlock(io); 180 self.connections.remove(&connection.node); 181 } 182 183 fn run(self: *Watchdog, io: std.Io) void { 184 while (true) { 185 io.sleep(watchdog_interval, .awake) catch return; 186 self.mutex.lock(io) catch return; 187 defer self.mutex.unlock(io); 188 var node = self.connections.first; 189 while (node) |n| : (node = n.next) { 190 const connection: *Connection = @fieldParentPtr("node", n); 191 if (connection.timedOut()) connection.stream.shutdown(io, .both) catch {}; 192 } 193 } 194 } 195 }; 196 197 fn runTuiSession(handler: *const SessionHandler, sess: *ssh.SessionCtx, pty: ssh.PtySize) !void { 198 // runTui owns the terminal, whose deinit restores the client's screen and 199 // runs as the function unwinds — so any error it returns leaves the TUI torn 200 // down and we can surface the failure on the restored screen before exiting. 201 runTui(handler, sess, pty) catch |tui_err| { 202 const err = sess.underlyingError(tui_err); 203 serve_common.logError(sess.conn.io, handler.err, "ssh tui session failed: {s}\n", .{@errorName(err)}); 204 var buf: [256]u8 = undefined; 205 const msg = std.fmt.bufPrint(&buf, "haxy ssh: {s}\r\n", .{@errorName(err)}) catch "haxy ssh: internal error\r\n"; 206 sess.writeBytes(msg) catch {}; 207 try sess.exit(1); 208 }; 209 } 210 211 fn runTui(handler: *const SessionHandler, sess: *ssh.SessionCtx, pty: ssh.PtySize) !void { 212 const allocator = sess.conn.allocator; 213 const io = sess.conn.io; 214 215 // some clients (notably scripted ssh with no local controlling tty) 216 // allocate a pty without ever sending a non-zero size. fall back to a 217 // conventional 80x24 in that case so render emits something. 218 var terminal_size = Size{ 219 .width = if (pty.width_cells == 0) 80 else pty.width_cells, 220 .height = if (pty.height_cells == 0) 24 else pty.height_cells, 221 }; 222 223 // session-lifetime allocations (login, prefs); Nav owns the per-page arenas. 224 var session_arena = std.heap.ArenaAllocator.init(allocator); 225 defer session_arena.deinit(); 226 227 const Repo = rp.Repo(.xit, evt.admin_repo_opts); 228 var repo = try Repo.open(io, allocator, .{ .path = handler.admin_repo_path }); 229 defer repo.deinit(io, allocator); 230 var ui_session = try ui.Session.init(&session_arena, &repo, .{}); 231 ui_session.is_terminal = true; 232 ui_session.web_port = handler.wui_port; 233 ui_session.data.git_http_port = handler.git_http_port; 234 ui_session.data.git_ssh_port = handler.git_ssh_port; 235 ui_session.data.git_ssh_prefix = handler.git_ssh_prefix; 236 // let page builders open on-disk repos 237 ui_session.io = io; 238 ui_session.users_dir = handler.users_dir; 239 240 var nav = try ui.Nav.init(allocator, &ui_session); 241 defer nav.deinit(allocator); 242 243 var session_writer_buf: [8192]u8 = undefined; 244 var session_writer = ssh.SessionWriter.init(sess, &session_writer_buf); 245 246 // the terminal's deinit writes leave-alt / show-cursor / disable-mouse and 247 // flushes, restoring the client's screen. as a function-scoped defer it runs 248 // before runTui returns — on the normal path and on any error — so the 249 // caller can write to the client afterward (and sess.exit can close cleanly). 250 var terminal_maybe: ?StreamTerminal = try StreamTerminal.init(allocator, &session_writer.interface, terminal_size); 251 defer if (terminal_maybe) |*terminal| terminal.deinit(); 252 253 // initial render — user sees the page immediately 254 if (terminal_maybe) |*terminal| { 255 try terminal.queryBackground(); 256 _ = try terminal.render(&nav.root); 257 } 258 259 // event loop. nextEvent blocks until something interesting arrives; 260 // for each event, rebuild the widget tree and re-render so the user 261 // sees the effect of their input on the same iteration. 262 event_loop: while (true) { 263 const event = try nextTuiEvent(sess, if (terminal_maybe) |*terminal| terminal else null); 264 if (event) |ev| switch (ev) { 265 .data => |payload| { 266 defer allocator.free(payload); 267 if (terminal_maybe) |*terminal| { 268 try terminal.writeBytes(payload); 269 } else { 270 // the copyable text stays up until enter 271 if (std.mem.indexOfAny(u8, payload, "\r\n") == null) continue; 272 terminal_maybe = try StreamTerminal.init(allocator, &session_writer.interface, terminal_size); 273 } 274 }, 275 .resize => |sz| { 276 terminal_size = .{ .width = sz.width_cells, .height = sz.height_cells }; 277 if (terminal_maybe) |*terminal| terminal.pushResize(terminal_size) else continue; 278 }, 279 .eof, .close => break :event_loop, 280 }; 281 if (terminal_maybe) |*terminal| { 282 while (terminal.popKey()) |key| { 283 try ui.inputKey(allocator, &nav.root, key, &ui_session); 284 } 285 } 286 287 if (ui_session.host_request) |request| { 288 ui_session.host_request = null; 289 switch (request) { 290 .show_copyable_text => |copyable_text| { 291 if (terminal_maybe) |*terminal| terminal.deinit(); 292 terminal_maybe = null; 293 try session_writer.interface.print("\x1b[2J\x1b[Hcopy the following text and then press enter to go back:\r\n\r\n{s}\r\n", .{copyable_text}); 294 try session_writer.interface.flush(); 295 continue; 296 }, 297 .sync_events => {}, 298 .undo => |target| ui.Repo.Undo.handleRequest(allocator, &ui_session, target), 299 } 300 } 301 302 // pick up data written by other handles so the next navigation 303 // builds its page from a current moment 304 try ui_session.reloadMoment(allocator, &repo); 305 306 // reconcile navigation: forward to a new page, or back on escape. 307 // the terminal background can change at any time, so recheck it on each page 308 if (try nav.sync(allocator, &ui_session)) { 309 if (terminal_maybe) |*terminal| try terminal.queryBackground(); 310 } 311 312 // the quit button (on the quit tab) asks the host to tear down 313 if (ui_session.quit_requested) break :event_loop; 314 315 try nav.root.build(allocator, .{ 316 .min_size = .{ .width = null, .height = null }, 317 .max_size = .{ .width = terminal_size.width, .height = terminal_size.height }, 318 }, nav.root.getFocus()); 319 if (terminal_maybe) |*terminal| _ = try terminal.render(&nav.root); 320 } 321 } 322 323 // only ambiguous input (a lone ESC or ESC ]) needs a deadline; longer 324 // fragments must remain buffered until complete. a timeout leaves partial SSH 325 // packets in the reader. 326 pub fn nextTuiEvent(sess: *ssh.SessionCtx, terminal: ?*StreamTerminal) !?ssh.Event { 327 if (terminal) |t| { 328 if (t.parser.isAmbiguous()) { 329 sess.conn.read_timeout = escape_timeout.toDeadline(sess.conn.io); 330 defer sess.conn.read_timeout = .none; 331 return sess.nextEvent() catch |err| switch (err) { 332 error.Timeout => { 333 try t.flushEscape(); 334 return null; 335 }, 336 else => return err, 337 }; 338 } 339 } 340 return try sess.nextEvent(); 341 } 342 343 // --------------------------------------------------------------------------- 344 // git path (exec) 345 // --------------------------------------------------------------------------- 346 347 const GitService = enum { upload_pack, receive_pack }; 348 349 const ParsedGitCommand = struct { 350 service: GitService, 351 dir: []u8, 352 353 fn deinit(self: ParsedGitCommand, allocator: std.mem.Allocator) void { 354 allocator.free(self.dir); 355 } 356 }; 357 358 fn runGitSession(handler: *const SessionHandler, sess: *ssh.SessionCtx, exec: ssh.Request.Exec) !void { 359 const allocator = sess.conn.allocator; 360 const io = sess.conn.io; 361 const protocol_version = xit.net_server_common.parseProtocolVersion(exec.git_protocol); 362 363 // the repo's pack functions consume the channel like any other stream. 364 // whatever they leave buffered is flushed before the exit status goes out. 365 var reader_buf: [4096]u8 = undefined; 366 var writer_buf: [4096]u8 = undefined; 367 var reader = ssh.SessionReader.init(sess, &reader_buf); 368 var writer = ssh.SessionWriter.init(sess, &writer_buf); 369 defer writer.interface.flush() catch {}; 370 371 const parsed = parseGitCommand(allocator, exec.command) catch return writeError(sess, "unsupported command (expected git-upload-pack or git-receive-pack)"); 372 defer parsed.deinit(allocator); 373 const repo_identity = std.mem.trimStart(u8, parsed.dir, "/"); 374 375 // a "+" names a fork's patch draft 376 if (std.mem.indexOfScalar(u8, repo_identity, '+') != null) { 377 return runForkSession(handler, sess, repo_identity, parsed.service, protocol_version, &reader.interface, &writer.interface); 378 } 379 380 const create_if_missing = parsed.service == .receive_pack; 381 382 const owner_repo = evt.parseOwnerRepoPath(repo_identity) orelse return writeError(sess, "repo path must be <owner>:<repo>"); 383 var author_arena = std.heap.ArenaAllocator.init(allocator); 384 defer author_arena.deinit(); 385 const author = switch (try authorizeRepoKey(io, &author_arena, handler.admin_repo_path, handler.users_dir, owner_repo.owner, owner_repo.name, parsed.service, &sess.fingerprint)) { 386 .allowed => |user| user, 387 .denied => return switch (parsed.service) { 388 .upload_pack => writeError(sess, "unauthorized: this SSH key cannot read this repo"), 389 .receive_pack => writeError(sess, "unauthorized: this SSH key cannot push to this repo"), 390 }, 391 .not_found => return writeError(sess, "repo not found"), 392 }; 393 394 const repo_path = switch (try serve_common.resolveRepoPath(io, allocator, handler.users_dir, handler.admin_repo_path, repo_identity, create_if_missing)) { 395 .ok => |p| p, 396 .invalid => unreachable, // parsed above 397 .not_found => return writeError(sess, "repo not found"), 398 }; 399 defer allocator.free(repo_path); 400 401 if (try serveIfExists(repo_path, handler.users_dir, &reader.interface, &writer.interface, io, allocator, parsed.service, protocol_version, author, handler.err, sess)) return; 402 403 if (!create_if_missing) return writeError(sess, "repo not found"); 404 405 // create the on-disk repo for the just-minted event and serve the push 406 var repo = try rp.Repo(.xit, any_repo_opts.toRepoOpts()).init(io, allocator, .{ .path = repo_path, .bare = true }); 407 defer repo.deinit(io, allocator); 408 try servePack(repo.self_repo_opts, &repo, handler.users_dir, &reader.interface, &writer.interface, io, allocator, parsed.service, protocol_version, author, handler.err, sess); 409 } 410 411 // serve a patch draft: anyone may fetch it, only its author may push to it 412 fn runForkSession( 413 handler: *const SessionHandler, 414 sess: *ssh.SessionCtx, 415 fork_path: []const u8, 416 service: GitService, 417 protocol_version: xit.net_server_common.ProtocolVersion, 418 reader: *std.Io.Reader, 419 writer: *std.Io.Writer, 420 ) !void { 421 const allocator = sess.conn.allocator; 422 const io = sess.conn.io; 423 424 const route = fork.parseRoute(fork_path) orelse return writeError(sess, "invalid fork path"); 425 // the route names the forker and the target repo 426 const forker_repo = evt.parseOwnerRepoPath(route.identity) orelse return writeError(sess, "repo path must be <forker>:<repo>"); 427 428 var admin = try rp.Repo(.xit, evt.admin_repo_opts).open(io, allocator, .{ .path = handler.admin_repo_path }); 429 defer admin.deinit(io, allocator); 430 var admin_arena = std.heap.ArenaAllocator.init(allocator); 431 defer admin_arena.deinit(); 432 const admin_moment = try evt.currentMoment(evt.admin_repo_opts, &admin); 433 const fork_id = try evt.parseEventId(&route.id); 434 const forker_id = (try evt.User.readIdByName(evt.AdminDB, evt.admin_repo_opts.hash, admin_moment, forker_repo.owner)) orelse 435 return writeError(sess, "patch draft not found"); 436 const fork_record = (try evt.readForkById(io, allocator, &admin_arena, handler.users_dir, &forker_id, &fork_id)) orelse 437 return writeError(sess, "patch draft not found"); 438 if (fork_record.removed) return writeError(sess, "patch draft not found"); 439 const user = (try evt.User.readById(evt.AdminDB, evt.admin_repo_opts.hash, admin_moment, &admin_arena, &forker_id)) orelse 440 return writeError(sess, "invalid patch draft"); 441 if (user.removed) return writeError(sess, "invalid patch draft"); 442 if (service == .receive_pack and !isKeyInAuthorizedKeys(user.event.ssh_keys, &sess.fingerprint)) 443 return writeError(sess, "unauthorized: this SSH key is not registered to the patch author"); 444 445 const draft_path = try fork.forkPath(allocator, handler.users_dir, &forker_id, &fork_id); 446 defer allocator.free(draft_path); 447 var draft = rp.AnyRepo(.xit, any_repo_opts).open(io, allocator, .{ .path = draft_path }) catch 448 return writeError(sess, "patch draft not found"); 449 defer draft.deinit(io, allocator); 450 if (service == .upload_pack) { 451 var sideband = progress.Sideband{ .writer = writer, .sess = sess }; 452 switch (draft) { 453 inline else => |*repo| try repo.uploadPack(io, allocator, reader, writer, .{ .protocol_version = protocol_version }, &sideband), 454 } 455 } else { 456 const target = (try evt.readRepoById(io, allocator, &admin_arena, handler.users_dir, fork_record.event.repo_user_id[0..evt.event_id_size], fork_record.event.repo_id[0..evt.event_id_size], null)) orelse 457 return writeError(sess, "repo not found"); 458 if (!std.mem.eql(u8, target.repo.event.name, forker_repo.name)) return writeError(sess, "patch draft belongs to another repo"); 459 const target_path = try evt.repoPath(allocator, handler.users_dir, fork_record.event.repo_user_id, fork_record.event.repo_id); 460 defer allocator.free(target_path); 461 const author: evt.CommitAuthor = .{ .name = user.event.name, .email = user.event.email }; 462 const timestamp: u64 = @intCast(std.Io.Timestamp.now(io, .real).toSeconds()); 463 switch (draft) { 464 inline else => |*repo| { 465 var target_repo = rp.Repo(.xit, repo.self_repo_opts).open(io, allocator, .{ .path = target_path }) catch 466 return writeError(sess, "repo not found or has the wrong hash"); 467 defer target_repo.deinit(io, allocator); 468 try push.receiveFork(repo.self_repo_opts, io, allocator, repo, &target_repo, handler.users_dir, &route.id, author, timestamp, reader, writer, handler.err, sess); 469 }, 470 } 471 } 472 } 473 474 // serve an existing repo at `repo_path`, or return false if none is there 475 fn serveIfExists( 476 repo_path: []const u8, 477 users_dir: []const u8, 478 reader: *std.Io.Reader, 479 writer: *std.Io.Writer, 480 io: std.Io, 481 allocator: std.mem.Allocator, 482 service: GitService, 483 protocol_version: xit.net_server_common.ProtocolVersion, 484 author: ?evt.CommitAuthor, 485 error_writer: *std.Io.Writer, 486 sess: ?*ssh.SessionCtx, 487 ) !bool { 488 // a bare open() creates the directory while probing for the repo, so only 489 // attempt it when the path already exists 490 std.Io.Dir.accessAbsolute(io, repo_path, .{}) catch return false; 491 492 var any_repo = rp.AnyRepo(.xit, any_repo_opts).open(io, allocator, .{ .path = repo_path }) catch |err| switch (err) { 493 error.RepoNotFound => return false, 494 else => |e| return e, 495 }; 496 defer any_repo.deinit(io, allocator); 497 498 switch (any_repo) { 499 inline else => |*repo| try servePack(repo.self_repo_opts, repo, users_dir, reader, writer, io, allocator, service, protocol_version, author, error_writer, sess), 500 } 501 return true; 502 } 503 504 fn servePack( 505 comptime repo_opts: rp.RepoOpts(.xit), 506 repo: *rp.Repo(.xit, repo_opts), 507 users_dir: []const u8, 508 reader: *std.Io.Reader, 509 writer: *std.Io.Writer, 510 io: std.Io, 511 allocator: std.mem.Allocator, 512 service: GitService, 513 protocol_version: xit.net_server_common.ProtocolVersion, 514 author: ?evt.CommitAuthor, 515 error_writer: *std.Io.Writer, 516 sess: ?*ssh.SessionCtx, 517 ) !void { 518 switch (service) { 519 .upload_pack => { 520 var sideband = progress.Sideband{ .writer = writer, .sess = sess }; 521 try repo.uploadPack(io, allocator, reader, writer, .{ .protocol_version = protocol_version }, &sideband); 522 }, 523 .receive_pack => try push.receivePackAndConsume(repo_opts, io, allocator, repo, reader, writer, .{ .protocol_version = protocol_version }, author, users_dir, error_writer, sess), 524 } 525 } 526 527 fn parseGitCommand(allocator: std.mem.Allocator, command: []const u8) !ParsedGitCommand { 528 var tokens = try std.process.Args.IteratorGeneral(.{ .single_quotes = true }).init(allocator, command); 529 defer tokens.deinit(); 530 531 const service_token = tokens.next() orelse return error.InvalidCommand; 532 const dir_token = tokens.next() orelse return error.InvalidCommand; 533 534 const service: GitService = 535 if (std.mem.eql(u8, service_token, "git-upload-pack") or std.mem.eql(u8, service_token, "upload-pack")) 536 .upload_pack 537 else if (std.mem.eql(u8, service_token, "git-receive-pack") or std.mem.eql(u8, service_token, "receive-pack")) 538 .receive_pack 539 else 540 return error.UnsupportedService; 541 542 return .{ .service = service, .dir = try allocator.dupe(u8, dir_token) }; 543 } 544 545 const RepoAuthorization = union(enum) { allowed: ?evt.CommitAuthor, denied, not_found }; 546 547 fn authorizeRepoKey( 548 io: std.Io, 549 arena: *std.heap.ArenaAllocator, 550 admin_repo_path: []const u8, 551 users_dir: []const u8, 552 owner_name: []const u8, 553 repo_name: []const u8, 554 service: GitService, 555 fingerprint: *const [ssh.fingerprint_len]u8, 556 ) !RepoAuthorization { 557 const allocator = arena.child_allocator; 558 var admin = rp.Repo(.xit, evt.admin_repo_opts).open(io, allocator, .{ .path = admin_repo_path }) catch |err| switch (err) { 559 error.RepoNotFound => return .not_found, 560 else => |e| return e, 561 }; 562 defer admin.deinit(io, allocator); 563 564 const moment = try evt.currentMoment(evt.admin_repo_opts, &admin); 565 // no viewer yet, so this carries the base role 566 const repo = (try evt.readRepoByOwnerAndName(io, allocator, arena, moment, users_dir, owner_name, repo_name, null)) orelse { 567 if (service == .upload_pack) return .not_found; 568 const owner = (try evt.User.readByName(io, allocator, admin_repo_path, arena, owner_name)) orelse return .not_found; 569 return if (isKeyInAuthorizedKeys(owner.event.ssh_keys, fingerprint)) 570 .{ .allowed = .{ .name = owner.event.name, .email = owner.event.email } } 571 else 572 .denied; 573 }; 574 575 const min_role: evt.Repo.Role = switch (service) { 576 .upload_pack => .read, 577 .receive_pack => .write, 578 }; 579 // skip the key lookups when the base role is enough 580 if (repo.role.atLeast(min_role)) return .{ .allowed = null }; 581 582 // the creator owns the repo 583 const owner_id = repo.repo.event.user_id[0..evt.event_id_size]; 584 if (try authorWithKey(moment, arena, owner_id, fingerprint)) |author| return .{ .allowed = author }; 585 586 // anyone else holding the key needs a grant with the role. a key can be 587 // shared, so a grant that falls short doesn't end the search. 588 for (try evt.readRepoGrants(io, allocator, arena, users_dir, owner_id, &repo.event_id)) |grant| { 589 if (!grant.role.atLeast(min_role)) continue; 590 if (try authorWithKey(moment, arena, grant.user_id, fingerprint)) |author| return .{ .allowed = author }; 591 } 592 return .denied; 593 } 594 595 // the user as a commit author, or null unless they hold the key 596 fn authorWithKey( 597 moment: evt.AdminDB.HashMap(.read_only), 598 arena: *std.heap.ArenaAllocator, 599 user_id: []const u8, 600 fingerprint: *const [ssh.fingerprint_len]u8, 601 ) !?evt.CommitAuthor { 602 const user = (try evt.User.readById(evt.AdminDB, evt.admin_repo_opts.hash, moment, arena, user_id)) orelse return null; 603 if (user.removed or !isKeyInAuthorizedKeys(user.event.ssh_keys, fingerprint)) return null; 604 return .{ .name = user.event.name, .email = user.event.email }; 605 } 606 607 fn isKeyInAuthorizedKeys(ssh_keys: []const u8, fingerprint: *const [ssh.fingerprint_len]u8) bool { 608 var it = std.mem.splitScalar(u8, ssh_keys, '\n'); 609 while (it.next()) |line| { 610 const fp = fingerprintOfAuthorizedKey(line) orelse continue; 611 if (std.mem.eql(u8, &fp, fingerprint)) return true; 612 } 613 return false; 614 } 615 616 // the SHA256 fingerprint of one authorized_keys line, or null if the line is 617 // blank or not a parseable "<type> <base64> [comment]" entry 618 fn fingerprintOfAuthorizedKey(line: []const u8) ?[ssh.fingerprint_len]u8 { 619 var it = std.mem.tokenizeAny(u8, line, " \t\r"); 620 _ = it.next() orelse return null; // key type 621 const blob_b64 = it.next() orelse return null; 622 623 const decoder = std.base64.standard.Decoder; 624 const blob_len = decoder.calcSizeForSlice(blob_b64) catch return null; 625 var blob_buf: [4096]u8 = undefined; 626 if (blob_len > blob_buf.len) return null; 627 decoder.decode(blob_buf[0..blob_len], blob_b64) catch return null; 628 629 return ssh.formatFingerprint(blob_buf[0..blob_len]); 630 } 631 632 fn writeError(sess: *ssh.SessionCtx, comptime msg: []const u8) !void { 633 const body = "ERR haxy ssh: " ++ msg; 634 var packet: [body.len + 4]u8 = undefined; 635 const line = try std.fmt.bufPrint(&packet, "{x:0>4}{s}", .{ packet.len, body }); 636 try sess.writeBytes(line); 637 try sess.exit(1); 638 } 639 640 test "parseGitCommand rejects malformed input" { 641 const allocator = std.testing.allocator; 642 try std.testing.expectError(error.InvalidCommand, parseGitCommand(allocator, "git-upload-pack")); 643 try std.testing.expectError(error.UnsupportedService, parseGitCommand(allocator, "ls -la")); 644 try std.testing.expectError(error.UnsupportedService, parseGitCommand(allocator, "git-fake-pack 'repo'")); 645 } 646 647 test "parseGitCommand happy paths" { 648 const allocator = std.testing.allocator; 649 650 { 651 const parsed = try parseGitCommand(allocator, "git-upload-pack 'some-repo'"); 652 defer parsed.deinit(allocator); 653 try std.testing.expectEqual(GitService.upload_pack, parsed.service); 654 try std.testing.expectEqualStrings("some-repo", parsed.dir); 655 } 656 { 657 const parsed = try parseGitCommand(allocator, "git-receive-pack 'user/proj'"); 658 defer parsed.deinit(allocator); 659 try std.testing.expectEqual(GitService.receive_pack, parsed.service); 660 try std.testing.expectEqualStrings("user/proj", parsed.dir); 661 } 662 { 663 const parsed = try parseGitCommand(allocator, "git-upload-pack repo"); 664 defer parsed.deinit(allocator); 665 try std.testing.expectEqual(GitService.upload_pack, parsed.service); 666 try std.testing.expectEqualStrings("repo", parsed.dir); 667 } 668 } 669