diff options
Diffstat (limited to 'src/quic.zig')
| -rw-r--r-- | src/quic.zig | 302 |
1 files changed, 302 insertions, 0 deletions
diff --git a/src/quic.zig b/src/quic.zig new file mode 100644 index 0000000..c78a79d --- /dev/null +++ b/src/quic.zig @@ -0,0 +1,302 @@ +const std = @import("std"); +const libc = std.c; + +/// QUIC transport with caller-selected ALPN. OpenSSL bindings are injected so +/// applications control linkage. Certificates are ephemeral and peers unauthenticated. +pub fn Quic(comptime ssl: type, comptime protocol: []const u8) type { + if (protocol.len == 0 or protocol.len > 255) @compileError("invalid ALPN length"); + return struct { + comptime { + if (ssl.OPENSSL_VERSION_NUMBER < 0x30600000) + @compileError("9P over QUIC requires OpenSSL 3.6 or newer"); + } + + pub const alpn = protocol; + pub const Error = error{ Tls, Socket, SocketFlags, SocketOption, Bind, Address, Closed, InvalidWrite }; + + pub const Listener = struct { + fd: c_int, + handle: *ssl.SSL, + address: std.Io.net.IpAddress, + + pub fn init(address: std.Io.net.IpAddress) Error!Listener { + ssl.ERR_clear_error(); + const ctx = ssl.SSL_CTX_new(ssl.OSSL_QUIC_server_method()) orelse return error.Tls; + defer ssl.SSL_CTX_free(ctx); + const key = ssl.EVP_PKEY_Q_keygen(null, null, "EC", @as([*:0]const u8, "prime256v1")) orelse return error.Tls; + defer ssl.EVP_PKEY_free(key); + const cert = ssl.X509_new() orelse return error.Tls; + defer ssl.X509_free(cert); + if (ssl.X509_set_version(cert, 2) != 1 or + ssl.ASN1_INTEGER_set(ssl.X509_get_serialNumber(cert), 1) != 1 or + ssl.X509_gmtime_adj(ssl.X509_getm_notBefore(cert), -60) == null or + ssl.X509_gmtime_adj(ssl.X509_getm_notAfter(cert), 365 * 24 * 60 * 60) == null or + ssl.X509_set_pubkey(cert, key) != 1) return error.Tls; + const name = ssl.X509_get_subject_name(cert) orelse return error.Tls; + if (ssl.X509_NAME_add_entry_by_txt(name, "CN", ssl.MBSTRING_ASC, protocol.ptr, @intCast(protocol.len), -1, 0) != 1 or + ssl.X509_set_issuer_name(cert, name) != 1 or + ssl.X509_sign(cert, key, ssl.EVP_sha256()) <= 0 or + ssl.SSL_CTX_use_certificate(ctx, cert) != 1 or + ssl.SSL_CTX_use_PrivateKey(ctx, key) != 1) return error.Tls; + ssl.SSL_CTX_set_verify(ctx, ssl.SSL_VERIFY_NONE, null); + ssl.SSL_CTX_set_alpn_select_cb(ctx, selectAlpn, null); + var addr: libc.sockaddr.storage = undefined; + const addr_len = sockaddr(address, &addr); + const fd = try udp(addr.family); + errdefer _ = libc.close(fd); + if (libc.bind(fd, @ptrCast(&addr), addr_len) != 0) return error.Bind; + var actual_len: libc.socklen_t = @sizeOf(@TypeOf(addr)); + if (libc.getsockname(fd, @ptrCast(&addr), &actual_len) != 0) return error.Address; + var actual = address; + actual.setPort(switch (address) { + .ip4 => std.mem.bigToNative(u16, @as(*const libc.sockaddr.in, @ptrCast(&addr)).port), + .ip6 => std.mem.bigToNative(u16, @as(*const libc.sockaddr.in6, @ptrCast(&addr)).port), + }); + const handle = ssl.SSL_new_listener(ctx, 0) orelse return error.Tls; + errdefer ssl.SSL_free(handle); + if (ssl.SSL_set_fd(handle, fd) != 1 or ssl.SSL_set_blocking_mode(handle, 0) != 1 or + ssl.SSL_listen(handle) != 1) return error.Tls; + return .{ .fd = fd, .handle = handle, .address = actual }; + } + + pub fn accept(l: *Listener) Error!?Connection { + ssl.ERR_clear_error(); + const handle = ssl.SSL_accept_connection(l.handle, ssl.SSL_ACCEPT_CONNECTION_NO_BLOCK) orelse { + if (ssl.ERR_peek_error() != 0) return error.Tls; + return null; + }; + errdefer ssl.SSL_free(handle); + if (ssl.SSL_set_default_stream_mode(handle, ssl.SSL_DEFAULT_STREAM_MODE_NONE) != 1 or + ssl.SSL_set_blocking_mode(handle, 0) != 1) return error.Tls; + return .{ .handle = handle }; + } + + pub fn events(l: *Listener) Error!void { + ssl.ERR_clear_error(); + if (ssl.SSL_handle_events(l.handle) != 1) return error.Tls; + } + + pub fn poll(l: *const Listener) libc.pollfd { + return pollFd(l.handle, l.fd); + } + + pub fn nextDue(l: *const Listener) ?i32 { + return due(l.handle); + } + + // Accepted connections must be released before the shared UDP socket. + pub fn deinit(l: *Listener) void { + ssl.SSL_free(l.handle); + _ = libc.close(l.fd); + l.* = undefined; + } + }; + + pub const Connection = struct { + handle: *ssl.SSL, + stream: ?*ssl.SSL = null, + fd: c_int = -1, + pending_write_len: usize = 0, + + pub fn dial(address: std.Io.net.IpAddress) Error!Connection { + ssl.ERR_clear_error(); + const ctx = ssl.SSL_CTX_new(ssl.OSSL_QUIC_client_method()) orelse return error.Tls; + defer ssl.SSL_CTX_free(ctx); + ssl.SSL_CTX_set_verify(ctx, ssl.SSL_VERIFY_NONE, null); + const fd = try udp(if (address == .ip4) libc.AF.INET else libc.AF.INET6); + errdefer _ = libc.close(fd); + const handle = ssl.SSL_new(ctx) orelse return error.Tls; + errdefer ssl.SSL_free(handle); + if (ssl.SSL_set_fd(handle, fd) != 1 or ssl.SSL_set_blocking_mode(handle, 0) != 1 or + ssl.SSL_set_default_stream_mode(handle, ssl.SSL_DEFAULT_STREAM_MODE_NONE) != 1) return error.Tls; + const protocols = [_]u8{alpn.len} ++ protocol[0..protocol.len].*; + if (ssl.SSL_set_alpn_protos(handle, &protocols, protocols.len) != 0) return error.Tls; + const peer = ssl.BIO_ADDR_new() orelse return error.Tls; + defer ssl.BIO_ADDR_free(peer); + const made = switch (address) { + .ip4 => |ip| ssl.BIO_ADDR_rawmake(peer, libc.AF.INET, &ip.bytes, ip.bytes.len, std.mem.nativeToBig(u16, ip.port)), + .ip6 => |ip| ssl.BIO_ADDR_rawmake(peer, libc.AF.INET6, &ip.bytes, ip.bytes.len, std.mem.nativeToBig(u16, ip.port)), + }; + if (made != 1 or ssl.SSL_set1_initial_peer_addr(handle, peer) != 1) return error.Tls; + return .{ .handle = handle, .fd = fd }; + } + + pub fn handshake(c: *Connection) Error!bool { + ssl.ERR_clear_error(); + var close_info: ssl.SSL_CONN_CLOSE_INFO = undefined; + if (ssl.SSL_get_conn_close_info(c.handle, &close_info, @sizeOf(@TypeOf(close_info))) == 1) + return error.Closed; + if (ssl.SSL_is_init_finished(c.handle) == 1) return true; + const rc = if (c.fd >= 0) ssl.SSL_connect(c.handle) else ssl.SSL_accept(c.handle); + if (rc == 1) return true; + try retry(c.handle, rc); + return false; + } + + fn ready(c: *Connection) Error!bool { + if (!try c.handshake()) return false; + if (c.stream != null) return true; + ssl.ERR_clear_error(); + const stream = if (c.fd >= 0) + ssl.SSL_new_stream(c.handle, ssl.SSL_STREAM_FLAG_NO_BLOCK) + else + ssl.SSL_accept_stream(c.handle, ssl.SSL_ACCEPT_STREAM_NO_BLOCK); + if (stream == null) { + if (ssl.ERR_peek_error() != 0) return error.Tls; + return false; + } + errdefer ssl.SSL_free(stream); + if (ssl.SSL_set_blocking_mode(stream, 0) != 1 or + ssl.SSL_get_stream_id(stream) != 0 or + ssl.SSL_set_incoming_stream_policy(c.handle, ssl.SSL_INCOMING_STREAM_POLICY_REJECT, 0) != 1) + return error.Tls; + _ = ssl.SSL_set_mode(stream, ssl.SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER); + c.stream = stream; + return true; + } + + pub fn read(c: *Connection, bytes: []u8) Error!?usize { + if (!try c.ready()) return null; + ssl.ERR_clear_error(); + var len: usize = 0; + const rc = ssl.SSL_read_ex(c.stream, bytes.ptr, bytes.len, &len); + if (rc == 1) return len; + if (ssl.SSL_get_error(c.stream, rc) == ssl.SSL_ERROR_ZERO_RETURN) return 0; + try retry(c.stream.?, rc); + return null; + } + + pub fn pending(c: *const Connection) bool { + var close_info: ssl.SSL_CONN_CLOSE_INFO = undefined; + if (ssl.SSL_get_conn_close_info(c.handle, &close_info, @sizeOf(@TypeOf(close_info))) == 1) return true; + if (c.stream) |stream| { + var item: ssl.SSL_POLL_ITEM = .{ .desc = ssl.SSL_as_poll_descriptor(stream), .events = ssl.SSL_POLL_EVENT_RE, .revents = 0 }; + const timeout: ssl.struct_timeval = .{ .tv_sec = 0, .tv_usec = 0 }; + if (ssl.SSL_poll(&item, 1, @sizeOf(@TypeOf(item)), &timeout, ssl.SSL_POLL_FLAG_NO_HANDLE_EVENTS, null) != 1) return true; + return item.revents != 0; + } + return ssl.SSL_get_accept_stream_queue_len(c.handle) != 0; + } + + pub fn write(c: *Connection, bytes: []const u8) Error!usize { + if (!try c.ready()) return 0; + if (bytes.len < c.pending_write_len) return error.InvalidWrite; + const requested = if (c.pending_write_len != 0) c.pending_write_len else bytes.len; + if (requested == 0) return 0; + ssl.ERR_clear_error(); + var len: usize = 0; + const rc = ssl.SSL_write_ex(c.stream, bytes.ptr, requested, &len); + if (rc == 1) { + c.pending_write_len = 0; + return len; + } + try retry(c.stream.?, rc); + c.pending_write_len = requested; + return 0; + } + + pub fn conclude(c: *Connection) Error!void { + if (c.pending_write_len != 0) return error.InvalidWrite; + if (!try c.ready()) return error.Closed; + ssl.ERR_clear_error(); + if (ssl.SSL_stream_conclude(c.stream, 0) != 1) return error.Tls; + } + + pub fn events(c: *Connection) Error!void { + if (c.fd < 0) return; + ssl.ERR_clear_error(); + if (ssl.SSL_handle_events(c.handle) != 1) return error.Tls; + } + + pub fn poll(c: *const Connection) ?libc.pollfd { + return if (c.fd >= 0) pollFd(c.handle, c.fd) else null; + } + + pub fn nextDue(c: *const Connection) ?i32 { + return if (c.fd >= 0) due(c.handle) else null; + } + + pub fn deinit(c: *Connection) void { + ssl.ERR_clear_error(); + _ = ssl.SSL_shutdown_ex(c.handle, ssl.SSL_SHUTDOWN_FLAG_RAPID | ssl.SSL_SHUTDOWN_FLAG_NO_STREAM_FLUSH | ssl.SSL_SHUTDOWN_FLAG_NO_BLOCK, null, 0); + ssl.SSL_free(c.stream); + ssl.SSL_free(c.handle); + if (c.fd >= 0) _ = libc.close(c.fd); + c.* = undefined; + } + }; + + fn udp(family: u16) Error!c_int { + const fd = libc.socket(family, libc.SOCK.DGRAM, 0); + if (fd < 0) return error.Socket; + errdefer _ = libc.close(fd); + const flags = libc.fcntl(fd, libc.F.GETFL, @as(c_int, 0)); + if (flags < 0) return error.SocketFlags; + var options: libc.O = @bitCast(@as(u32, @bitCast(flags))); + options.NONBLOCK = true; + if (libc.fcntl(fd, libc.F.SETFL, @as(c_int, @bitCast(@as(u32, @bitCast(options))))) != 0 or + libc.fcntl(fd, libc.F.SETFD, @as(c_int, libc.FD_CLOEXEC)) != 0) return error.SocketFlags; + if (family == libc.AF.INET6) { + const enabled: c_int = 1; + const v6only = if (@import("builtin").os.tag.isDarwin()) 27 else libc.IPV6.V6ONLY; + if (libc.setsockopt(fd, libc.IPPROTO.IPV6, v6only, &enabled, @sizeOf(c_int)) != 0) return error.SocketOption; + } + return fd; + } + + fn sockaddr(address: std.Io.net.IpAddress, out: *libc.sockaddr.storage) libc.socklen_t { + switch (address) { + .ip4 => |ip| { + const addr: *libc.sockaddr.in = @ptrCast(out); + addr.* = .{ .port = std.mem.nativeToBig(u16, ip.port), .addr = @bitCast(ip.bytes) }; + return @sizeOf(libc.sockaddr.in); + }, + .ip6 => |ip| { + const addr: *libc.sockaddr.in6 = @ptrCast(out); + addr.* = .{ .port = std.mem.nativeToBig(u16, ip.port), .addr = ip.bytes, .flowinfo = 0, .scope_id = 0 }; + return @sizeOf(libc.sockaddr.in6); + }, + } + } + + fn pollFd(handle: *ssl.SSL, fd: c_int) libc.pollfd { + var result: libc.pollfd = .{ .fd = fd, .events = 0, .revents = 0 }; + if (ssl.SSL_net_read_desired(handle) == 1) result.events |= libc.POLL.IN; + if (ssl.SSL_net_write_desired(handle) == 1) result.events |= libc.POLL.OUT; + return result; + } + + fn due(handle: *ssl.SSL) ?i32 { + var tv: ssl.struct_timeval = undefined; + var infinite: c_int = undefined; + if (ssl.SSL_get_event_timeout(handle, &tv, &infinite) != 1) return 0; + if (infinite != 0) return null; + const ms = @as(i128, tv.tv_sec) * 1000 + @divFloor(@as(i128, tv.tv_usec) + 999, 1000); + return @intCast(std.math.clamp(ms, 0, std.math.maxInt(i32))); + } + + fn retry(handle: *ssl.SSL, rc: c_int) Error!void { + switch (ssl.SSL_get_error(handle, rc)) { + ssl.SSL_ERROR_WANT_READ, ssl.SSL_ERROR_WANT_WRITE => {}, + ssl.SSL_ERROR_ZERO_RETURN => return error.Closed, + else => return error.Tls, + } + } + + fn selectAlpn(_: ?*ssl.SSL, out: [*c][*c]const u8, outlen: [*c]u8, input: [*c]const u8, len: c_uint, _: ?*anyopaque) callconv(.c) c_int { + var offset: usize = 0; + while (offset < len) { + const size = input[offset]; + offset += 1; + if (size > len - offset) return ssl.SSL_TLSEXT_ERR_ALERT_FATAL; + if (std.mem.eql(u8, input[offset..][0..size], alpn)) { + out.* = input + offset; + outlen.* = size; + return ssl.SSL_TLSEXT_ERR_OK; + } + offset += size; + } + return ssl.SSL_TLSEXT_ERR_ALERT_FATAL; + } + }; +} |