╭─────────────╮ │scroll to top│ ╰─────────────╯ ╭ serve_ssh_protocol.zig ───────────────────────────────────────╮ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ ╰───────────────────────────────────────────────────────────────╯
🬐 🬠 🬞🬂🬏 🬟 🬑 🬟 🬑 ╭478b827a..╮ 478b827a.. see-em: 🬋🬋🬋 🬋🬋🬋 🬋 🬋 │files │ commits refs discuss issues new login 🬐 🬠 🬐 🬠 🬑 🬟 🬰 ╰──────────╯ (527) 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 patch.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
1739 pub fn appendPublickeySignedData( 1740 buf: *std.ArrayList(u8), 1741 allocator: std.mem.Allocator, 1742 session_id: []const u8, 1743 user_name: []const u8, 1744 service_name: []const u8, 1745 algo: []const u8, 1746 pubkey_blob: []const u8, 1747 ) !void { 1748 try writeStringField(buf, allocator, session_id); 1749 try buf.append(allocator, SSH_MSG_USERAUTH_REQUEST); 1750 try writeStringField(buf, allocator, user_name); 1751 try writeStringField(buf, allocator, service_name); 1752 try writeStringField(buf, allocator, "publickey"); 1753 try buf.append(allocator, 1); 1754 try writeStringField(buf, allocator, algo); 1755 try writeStringField(buf, allocator, pubkey_blob); 1756 } 1757 1758 // build the bytes a publickey signature is computed over (RFC 4252 §7) and 1759 // verify the supplied signature against them. 1760 fn verifyUserauthSignature( 1761 allocator: std.mem.Allocator, 1762 session_id: *const [Sha256.digest_length]u8, 1763 user_name: []const u8, 1764 service_name: []const u8, 1765 algo: []const u8, 1766 pubkey_blob: []const u8, 1767 signature_blob: []const u8, 1768 ) !bool { 1769 var signed: std.ArrayList(u8) = .empty; 1770 defer signed.deinit(allocator); 1771 try appendPublickeySignedData(&signed, allocator, session_id, user_name, service_name, algo, pubkey_blob); 1772 1773 // parse pubkey_blob: string "ssh-ed25519" || string raw_pubkey 1774 var pubkey_reader = std.Io.Reader.fixed(pubkey_blob); 1775 const pk_algo = try takeString(&pubkey_reader, 64); 1776 if (!std.mem.eql(u8, pk_algo, "ssh-ed25519")) return false; 1777 const raw_pubkey = try takeString(&pubkey_reader, 64); 1778 if (raw_pubkey.len != Ed25519.PublicKey.encoded_length) return false; 1779 1780 // parse signature_blob: string "ssh-ed25519" || string raw_signature 1781 var sig_reader = std.Io.Reader.fixed(signature_blob); 1782 const sig_algo = try takeString(&sig_reader, 64); 1783 if (!std.mem.eql(u8, sig_algo, "ssh-ed25519")) return false; 1784 const raw_sig = try takeString(&sig_reader, Ed25519.Signature.encoded_length); 1785 if (raw_sig.len != Ed25519.Signature.encoded_length) return false; 1786 1787 var pubkey_bytes: [Ed25519.PublicKey.encoded_length]u8 = undefined; 1788 @memcpy(&pubkey_bytes, raw_pubkey); 1789 var sig_bytes: [Ed25519.Signature.encoded_length]u8 = undefined; 1790 @memcpy(&sig_bytes, raw_sig); 1791 1792 const pk = Ed25519.PublicKey.fromBytes(pubkey_bytes) catch return false; 1793 const sig = Ed25519.Signature.fromBytes(sig_bytes); 1794 sig.verify(signed.items, pk) catch return false; 1795 return true; 1796 } 1797 1798 // --------------------------------------------------------------------------- 1799 // connection layer (RFC 4254): channels, requests, data, flow control 1800 // --------------------------------------------------------------------------- 1801 1802 const Channel = struct { 1803 local_id: u32, 1804 remote_id: u32, 1805 local_window: u32, // bytes peer may still send us before we adjust 1806 remote_window: u32, // bytes we may still send to peer before they adjust 1807 max_packet: u32, // max CHANNEL_DATA payload the peer accepts in one packet 1808 pty: ?PtySize = null, 1809 // value of GIT_PROTOCOL, the one env variable we keep 1810 git_protocol_buf: [64]u8 = undefined, 1811 git_protocol_len: ?usize = null, 1812 }; 1813 1814 pub const PtySize = struct { width_cells: u16, height_cells: u16 }; 1815 1816 // take the uint32 width/height cell counts of a pty-req or window-change, 1817 // bounded before either initial rendering or a resize can allocate grids. 1818 // keep zero dimensions intact (unspecified at startup, minimized on resize). 1819 fn takePtySize(r: *std.Io.Reader) !PtySize { 1820 const width = @min(try r.takeInt(u32, .big), max_pty_width); 1821 const height = @min(try r.takeInt(u32, .big), max_pty_height); 1822 return .{ 1823 .width_cells = @intCast(width), 1824 .height_cells = @intCast(height), 1825 }; 1826 } 1827 1828 fn runChannelLayer( 1829 conn: *Conn, 1830 fingerprint: *const [fingerprint_len]u8, 1831 handler: anytype, 1832 ) !void { 1833 const allocator = conn.allocator; 1834 var channel: ?Channel = null; 1835 1836 while (true) { 1837 const packet = try readSessionPacket(conn); 1838 defer allocator.free(packet); 1839 const msg_type = packet[0]; 1840 1841 switch (msg_type) { 1842 SSH_MSG_GLOBAL_REQUEST => try handleGlobalRequest(conn, packet), 1843 1844 SSH_MSG_CHANNEL_OPEN => { 1845 channel = try handleChannelOpen(conn, packet, channel != null) orelse continue; 1846 }, 1847 1848 SSH_MSG_CHANNEL_REQUEST => { 1849 const ch = if (channel) |*c| c else continue; 1850 const start_request = try handleChannelRequest(conn, ch, packet); 1851 // the request borrows from the packet, which outlives the session 1852 if (start_request) |request| { 1853 // any key authenticates, so the deadline holds until here 1854 conn.idle.session_started.store(true, .release); 1855 var sess = SessionCtx{ 1856 .conn = conn, 1857 .channel = ch, 1858 .fingerprint = fingerprint.*, 1859 }; 1860 defer sess.deinit(); 1861 handler.handleSession(&sess, request) catch |session_err| { 1862 // try to send a non-zero exit status before closing 1863 sess.exit(1) catch {}; 1864 return sess.underlyingError(session_err); 1865 }; 1866 if (!sess.closed) try sess.exit(0); 1867 return; 1868 } 1869 }, 1870 1871 SSH_MSG_CHANNEL_WINDOW_ADJUST => { 1872 const ch = if (channel) |*c| c else continue; 1873 try handleWindowAdjust(ch, packet); 1874 }, 1875 1876 SSH_MSG_CHANNEL_DATA, SSH_MSG_CHANNEL_EXTENDED_DATA => { 1877 const ch = if (channel) |*c| c else continue; 1878 // before shell/exec the client shouldn't be sending data, but 1879 // some clients are chatty; discard and refill window. nothing 1880 // is buffered yet, so the whole window is available to credit. 1881 try discardChannelData(ch, packet, msg_type == SSH_MSG_CHANNEL_EXTENDED_DATA); 1882 try maybeRefillRecvWindow(conn, ch, initial_recv_window); 1883 }, 1884 1885 SSH_MSG_CHANNEL_EOF => { 1886 if (channel) |*c| try parseChannelId(packet, c.local_id); 1887 }, 1888 1889 SSH_MSG_CHANNEL_CLOSE => { 1890 if (channel) |*c| { 1891 try parseChannelId(packet, c.local_id); 1892 try sendChannelMessage(conn, c, SSH_MSG_CHANNEL_CLOSE); 1893 drainConnection(conn); 1894 } 1895 return; 1896 }, 1897 1898 // RFC 4252 §5.1: silently ignored once authenticated 1899 SSH_MSG_USERAUTH_REQUEST => {}, 1900 else => try sendUnimplemented(conn), 1901 } 1902 } 1903 } 1904 1905 fn handleGlobalRequest(conn: *Conn, packet: []const u8) !void { 1906 // byte SSH_MSG_GLOBAL_REQUEST 1907 // string request_name 1908 // boolean want_reply 1909 // …request-specific data we ignore 1910 var r = std.Io.Reader.fixed(packet[1..]); 1911 _ = try takeString(&r, 256); 1912 const want_reply = (try r.takeByte()) != 0; 1913 if (want_reply) { 1914 try conn.writePacket(&.{&[_]u8{SSH_MSG_REQUEST_FAILURE}}); 1915 } 1916 } 1917 1918 /// parse a CHANNEL_OPEN. on a session channel, send CHANNEL_OPEN_CONFIRMATION 1919 /// and return the new Channel. on other types, send CHANNEL_OPEN_FAILURE and 1920 /// return null. 1921 fn handleChannelOpen(conn: *Conn, packet: []const u8, has_channel: bool) !?Channel { 1922 // byte SSH_MSG_CHANNEL_OPEN 1923 // string channel_type 1924 // uint32 sender_channel (peer's id) 1925 // uint32 initial_window 1926 // uint32 max_packet 1927 var r = std.Io.Reader.fixed(packet[1..]); 1928 const ch_type = try takeString(&r, 64); 1929 const remote_id = try r.takeInt(u32, .big); 1930 const initial_window = try r.takeInt(u32, .big); 1931 const max_packet = try r.takeInt(u32, .big); 1932 1933 if (has_channel) { 1934 try sendChannelOpenFailure(conn, remote_id, SSH_OPEN_RESOURCE_SHORTAGE, "only one channel per connection"); 1935 return null; 1936 } 1937 1938 if (!std.mem.eql(u8, ch_type, "session")) { 1939 try sendChannelOpenFailure(conn, remote_id, SSH_OPEN_UNKNOWN_CHANNEL_TYPE, "only session channels are supported"); 1940 return null; 1941 } 1942 1943 // a zero max_packet would leave writeBytes looping without progress 1944 if (max_packet == 0) { 1945 try sendChannelOpenFailure(conn, remote_id, SSH_OPEN_RESOURCE_SHORTAGE, "max packet size must be non-zero"); 1946 return null; 1947 } 1948 1949 const local_id: u32 = 0; // single-channel connection — id is always 0 from our side 1950 var reply: [17]u8 = undefined; 1951 reply[0] = SSH_MSG_CHANNEL_OPEN_CONFIRMATION; 1952 std.mem.writeInt(u32, reply[1..5], remote_id, .big); 1953 std.mem.writeInt(u32, reply[5..9], local_id, .big); 1954 std.mem.writeInt(u32, reply[9..13], initial_recv_window, .big); 1955 std.mem.writeInt(u32, reply[13..17], max_packet_size, .big); 1956 try conn.writePacket(&.{&reply}); 1957 1958 return .{ 1959 .local_id = local_id, 1960 .remote_id = remote_id, 1961 .local_window = initial_recv_window, 1962 .remote_window = initial_window, 1963 .max_packet = max_packet, 1964 }; 1965 } 1966 1967 fn sendChannelOpenFailure(conn: *Conn, remote_id: u32, reason: u32, description: []const u8) !void { 1968 const allocator = conn.allocator; 1969 1970 var reply: std.ArrayList(u8) = .empty; 1971 defer reply.deinit(allocator); 1972 try reply.append(allocator, SSH_MSG_CHANNEL_OPEN_FAILURE); 1973 try writeU32(&reply, allocator, remote_id); 1974 try writeU32(&reply, allocator, reason); 1975 try writeStringField(&reply, allocator, description); 1976 try writeStringField(&reply, allocator, ""); // language tag 1977 try conn.writePacket(&.{reply.items}); 1978 } 1979 1980 /// returns the session request if this one triggered it, else null. an exec 1981 /// command borrows from `packet`. 1982 fn handleChannelRequest(conn: *Conn, ch: *Channel, packet: []const u8) !?Request { 1983 // byte SSH_MSG_CHANNEL_REQUEST 1984 // uint32 recipient_channel (== our local_id) 1985 // string request_type 1986 // boolean want_reply 1987 // …request-specific data 1988 var r = std.Io.Reader.fixed(packet[1..]); 1989 const recipient_channel = try r.takeInt(u32, .big); 1990 if (recipient_channel != ch.local_id) return error.UnknownChannel; 1991 const req_type = try takeString(&r, 64); 1992 const want_reply = (try r.takeByte()) != 0; 1993 1994 if (std.mem.eql(u8, req_type, "pty-req")) { 1995 // string TERM, uint32 width chars, uint32 height rows, uint32 width px, 1996 // uint32 height px, string modes 1997 _ = try takeString(&r, 64); 1998 ch.pty = try takePtySize(&r); 1999 try replyChannelRequest(conn, ch, want_reply, true); 2000 return null; 2001 } 2002 2003 if (std.mem.eql(u8, req_type, "env")) { 2004 // string name, string value. the rest are ignored silently. 2005 const name = try takeString(&r, max_packet_len); 2006 const value = try takeString(&r, max_packet_len); 2007 if (std.mem.eql(u8, name, "GIT_PROTOCOL") and value.len <= ch.git_protocol_buf.len) { 2008 @memcpy(ch.git_protocol_buf[0..value.len], value); 2009 ch.git_protocol_len = value.len; 2010 } 2011 try replyChannelRequest(conn, ch, want_reply, true); 2012 return null; 2013 } 2014 2015 if (std.mem.eql(u8, req_type, "window-change")) { 2016 // uint32 width cells, uint32 height rows, uint32 width px, uint32 height px 2017 const sz = try takePtySize(&r); 2018 if (ch.pty != null) ch.pty = sz; 2019 // spec: window-change MUST NOT request a reply, but accept either 2020 try replyChannelRequest(conn, ch, want_reply, true); 2021 return null; 2022 } 2023 2024 if (std.mem.eql(u8, req_type, "shell")) { 2025 try replyChannelRequest(conn, ch, want_reply, true); 2026 return .{ .shell = ch.pty }; 2027 } 2028 2029 if (std.mem.eql(u8, req_type, "exec")) { 2030 // capture the command string for the handler to inspect 2031 const cmd = try takeString(&r, 4096); 2032 try replyChannelRequest(conn, ch, want_reply, true); 2033 return .{ .exec = .{ 2034 .command = cmd, 2035 .git_protocol = if (ch.git_protocol_len) |len| ch.git_protocol_buf[0..len] else null, 2036 } }; 2037 } 2038 2039 // unknown request kind — fail it 2040 try replyChannelRequest(conn, ch, want_reply, false); 2041 return null; 2042 } 2043 2044 fn replyChannelRequest(conn: *Conn, ch: *Channel, want_reply: bool, success: bool) !void { 2045 if (!want_reply) return; 2046 try sendChannelMessage(conn, ch, if (success) SSH_MSG_CHANNEL_SUCCESS else SSH_MSG_CHANNEL_FAILURE); 2047 } 2048 2049 fn sendChannelMessage(conn: *Conn, ch: *Channel, msg_type: u8) !void { 2050 var packet: [5]u8 = undefined; 2051 packet[0] = msg_type; 2052 std.mem.writeInt(u32, packet[1..5], ch.remote_id, .big); 2053 try conn.writePacket(&.{&packet}); 2054 } 2055 2056 fn handleWindowAdjust(ch: *Channel, packet: []const u8) !void { 2057 // byte SSH_MSG_CHANNEL_WINDOW_ADJUST 2058 // uint32 recipient_channel 2059 // uint32 bytes_to_add 2060 var r = std.Io.Reader.fixed(packet[1..]); 2061 const recipient_channel = try r.takeInt(u32, .big); 2062 if (recipient_channel != ch.local_id) return error.UnknownChannel; 2063 const add = try r.takeInt(u32, .big); 2064 ch.remote_window +|= add; 2065 } 2066 2067 // charge a payload's bytes against the receive window without keeping them. 2068 // the caller credits the window back, choosing the budget that suits it. 2069 fn discardChannelData(ch: *Channel, packet: []const u8, extended: bool) !void { 2070 // byte SSH_MSG_CHANNEL_DATA/EXTENDED_DATA 2071 // uint32 recipient_channel 2072 // [if extended: uint32 type_code] 2073 // string data 2074 const payload = try parseChannelData(packet, extended, ch.local_id); 2075 const data_len: u32 = @intCast(payload.len); 2076 2077 if (data_len > ch.local_window) return error.WindowExceeded; 2078 ch.local_window -= data_len; 2079 } 2080 2081 pub fn parseChannelData(packet: []const u8, extended: bool, expected_channel: u32) ![]const u8 { 2082 if (packet.len < 1) return error.EmptyPacket; 2083 var r = std.Io.Reader.fixed(packet[1..]); 2084 const recipient_channel = try r.takeInt(u32, .big); 2085 if (recipient_channel != expected_channel) return error.UnknownChannel; 2086 if (extended) { 2087 const data_type = try r.takeInt(u32, .big); 2088 if (data_type != SSH_EXTENDED_DATA_STDERR) return error.UnsupportedExtendedData; 2089 } 2090 const data_len = try r.takeInt(u32, .big); 2091 // catches both data_len > remaining (would otherwise be a bounds-check 2092 // panic on the slice) and trailing junk after the declared payload. 2093 if (data_len != r.buffered().len) return error.InvalidChannelData; 2094 return r.buffered(); 2095 } 2096 2097 fn parseChannelId(packet: []const u8, expected_channel: u32) !void { 2098 var r = std.Io.Reader.fixed(packet[1..]); 2099 const recipient_channel = try r.takeInt(u32, .big); 2100 if (recipient_channel != expected_channel) return error.UnknownChannel; 2101 if (r.buffered().len != 0) return error.InvalidChannelMessage; 2102 } 2103 2104 /// send a CHANNEL_WINDOW_ADJUST if our receive window has dipped below half 2105 /// of `budget`, the credit we're willing to have outstanding. used both for 2106 /// the pre-session discard path and by SessionCtx after it consumes a 2107 /// CHANNEL_DATA payload. 2108 fn maybeRefillRecvWindow(conn: *Conn, ch: *Channel, budget: u32) !void { 2109 if (ch.local_window >= budget / 2) return; 2110 const add = budget - ch.local_window; 2111 ch.local_window += add; 2112 var packet: [9]u8 = undefined; 2113 packet[0] = SSH_MSG_CHANNEL_WINDOW_ADJUST; 2114 std.mem.writeInt(u32, packet[1..5], ch.remote_id, .big); 2115 std.mem.writeInt(u32, packet[5..9], add, .big); 2116 try conn.writePacket(&.{&packet}); 2117 } 2118 2119 pub fn writeU32(buf: *std.ArrayList(u8), allocator: std.mem.Allocator, value: u32) !void { 2120 var bytes: [4]u8 = undefined; 2121 std.mem.writeInt(u32, &bytes, value, .big); 2122 try buf.appendSlice(allocator, &bytes); 2123 } 2124 2125 test "pty dimensions have bounded axes, preserving normal and zero sizes" { 2126 for ([_]struct { width: u32, height: u32, expected: PtySize }{ 2127 .{ .width = 80, .height = 24, .expected = .{ .width_cells = 80, .height_cells = 24 } }, 2128 .{ .width = 0, .height = 0, .expected = .{ .width_cells = 0, .height_cells = 0 } }, 2129 .{ .width = 0xffffffff, .height = 0xffffffff, .expected = .{ .width_cells = 512, .height_cells = 128 } }, 2130 }) |case| { 2131 var bytes: [8]u8 = undefined; 2132 std.mem.writeInt(u32, bytes[0..4], case.width, .big); 2133 std.mem.writeInt(u32, bytes[4..8], case.height, .big); 2134 var reader = std.Io.Reader.fixed(&bytes); 2135 try std.testing.expectEqual(case.expected, try takePtySize(&reader)); 2136 } 2137 } 2138 2139 test "channel close before shell or exec is acknowledged" { 2140 const io = std.testing.io; 2141 const allocator = std.testing.allocator; 2142 const key = [_]u8{0x5a} ** 64; 2143 var encoded: [256]u8 = undefined; 2144 var encoded_writer = std.Io.Writer.fixed(&encoded); 2145 var sender = Cipher.init(&key, 0); 2146 var open: std.ArrayList(u8) = .empty; 2147 defer open.deinit(allocator); 2148 try open.append(allocator, SSH_MSG_CHANNEL_OPEN); 2149 try writeStringField(&open, allocator, "session"); 2150 try writeU32(&open, allocator, 7); 2151 try writeU32(&open, allocator, 32768); 2152 try writeU32(&open, allocator, 32768); 2153 try sender.writePacket(io, &encoded_writer, &.{open.items}); 2154 try sender.writePacket(io, &encoded_writer, &.{&.{ SSH_MSG_CHANNEL_CLOSE, 0, 0, 0, 0 }}); 2155 var reader = std.Io.Reader.fixed(encoded_writer.buffered()); 2156 var output: [256]u8 = undefined; 2157 var writer = std.Io.Writer.fixed(&output); 2158 var idle = IdleState{}; 2159 var conn = Conn{ 2160 .io = io, 2161 .allocator = allocator, 2162 .reader = &reader, 2163 .writer = &writer, 2164 .cs_cipher = Cipher.init(&key, 0), 2165 .sc_cipher = Cipher.init(&key, 0), 2166 .rekey = undefined, 2167 .idle = &idle, 2168 }; 2169 const Handler = struct { 2170 pub fn handleSession(_: *@This(), _: *SessionCtx, _: Request) !void { 2171 return error.UnexpectedSession; 2172 } 2173 }; 2174 var handler = Handler{}; 2175 try runChannelLayer(&conn, &([_]u8{0} ** fingerprint_len), &handler); 2176 var output_reader = std.Io.Reader.fixed(writer.buffered()); 2177 var receiver = Cipher.init(&key, 0); 2178 const confirmation = try receiver.readPacket(allocator, &output_reader); 2179 defer allocator.free(confirmation); 2180 try std.testing.expectEqual(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, confirmation[0]); 2181 const close = try receiver.readPacket(allocator, &output_reader); 2182 defer allocator.free(close); 2183 try std.testing.expectEqualSlices(u8, &.{ SSH_MSG_CHANNEL_CLOSE, 0, 0, 0, 7 }, close); 2184 try std.testing.expectEqual(0, output_reader.buffered().len); 2185 } 2186