mirror of
https://github.com/lightpanda-io/browser.git
synced 2026-03-22 04:34:44 +00:00
733 lines
27 KiB
Zig
733 lines
27 KiB
Zig
// Copyright (C) 2023-2026 Lightpanda (Selecy SAS)
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//
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// Francis Bouvier <francis@lightpanda.io>
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// Pierre Tachoire <pierre@lightpanda.io>
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//
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// This program is free software: you can redistribute it and/or modify
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// it under the terms of the GNU Affero General Public License as
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// published by the Free Software Foundation, either version 3 of the
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// License, or (at your option) any later version.
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//
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// This program is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU Affero General Public License for more details.
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//
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// You should have received a copy of the GNU Affero General Public License
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// along with this program. If not, see <https://www.gnu.org/licenses/>.
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const std = @import("std");
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const builtin = @import("builtin");
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const posix = std.posix;
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const Allocator = std.mem.Allocator;
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const ArenaAllocator = std.heap.ArenaAllocator;
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const log = @import("lightpanda").log;
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const assert = @import("lightpanda").assert;
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const CDP_MAX_MESSAGE_SIZE = @import("../Config.zig").CDP_MAX_MESSAGE_SIZE;
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const Fragments = struct {
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type: Message.Type,
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message: std.ArrayList(u8),
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};
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pub const Message = struct {
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type: Type,
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data: []const u8,
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cleanup_fragment: bool,
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pub const Type = enum {
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text,
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binary,
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close,
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ping,
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pong,
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};
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};
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// These are the only websocket types that we're currently sending
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const OpCode = enum(u8) {
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text = 128 | 1,
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close = 128 | 8,
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pong = 128 | 10,
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};
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// WebSocket message reader. Given websocket message, acts as an iterator that
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// can return zero or more Messages. When next returns null, any incomplete
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// message will remain in reader.data
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pub fn Reader(comptime EXPECT_MASK: bool) type {
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return struct {
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allocator: Allocator,
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// position in buf of the start of the next message
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pos: usize = 0,
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// position in buf up until where we have valid data
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// (any new reads must be placed after this)
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len: usize = 0,
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// we add 140 to allow 1 control message (ping/pong/close) to be
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// fragmented into a normal message.
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buf: []u8,
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fragments: ?Fragments = null,
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const Self = @This();
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pub fn init(allocator: Allocator) !Self {
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const buf = try allocator.alloc(u8, 16 * 1024);
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return .{
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.buf = buf,
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.allocator = allocator,
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};
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}
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pub fn deinit(self: *Self) void {
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self.cleanup();
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self.allocator.free(self.buf);
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}
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pub fn cleanup(self: *Self) void {
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if (self.fragments) |*f| {
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f.message.deinit(self.allocator);
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self.fragments = null;
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}
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}
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pub fn readBuf(self: *Self) []u8 {
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// We might have read a partial http or websocket message.
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// Subsequent reads must read from where we left off.
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return self.buf[self.len..];
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}
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pub fn next(self: *Self) !?Message {
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LOOP: while (true) {
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var buf = self.buf[self.pos..self.len];
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const length_of_len, const message_len = extractLengths(buf) orelse {
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// we don't have enough bytes
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return null;
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};
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const byte1 = buf[0];
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if (byte1 & 112 != 0) {
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return error.ReservedFlags;
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}
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if (comptime EXPECT_MASK) {
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if (buf[1] & 128 != 128) {
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// client -> server messages _must_ be masked
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return error.NotMasked;
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}
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} else if (buf[1] & 128 != 0) {
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// server -> client are never masked
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return error.Masked;
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}
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var is_control = false;
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var is_continuation = false;
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var message_type: Message.Type = undefined;
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switch (byte1 & 15) {
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0 => is_continuation = true,
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1 => message_type = .text,
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2 => message_type = .binary,
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8 => {
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is_control = true;
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message_type = .close;
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},
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9 => {
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is_control = true;
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message_type = .ping;
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},
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10 => {
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is_control = true;
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message_type = .pong;
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},
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else => return error.InvalidMessageType,
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}
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if (is_control) {
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if (message_len > 125) {
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return error.ControlTooLarge;
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}
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} else if (message_len > CDP_MAX_MESSAGE_SIZE) {
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return error.TooLarge;
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} else if (message_len > self.buf.len) {
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const len = self.buf.len;
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self.buf = try growBuffer(self.allocator, self.buf, message_len);
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buf = self.buf[0..len];
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// we need more data
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return null;
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} else if (buf.len < message_len) {
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// we need more data
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return null;
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}
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// prefix + length_of_len + mask
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const header_len = 2 + length_of_len + if (comptime EXPECT_MASK) 4 else 0;
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const payload = buf[header_len..message_len];
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if (comptime EXPECT_MASK) {
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mask(buf[header_len - 4 .. header_len], payload);
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}
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// whatever happens after this, we know where the next message starts
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self.pos += message_len;
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const fin = byte1 & 128 == 128;
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if (is_continuation) {
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const fragments = &(self.fragments orelse return error.InvalidContinuation);
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if (fragments.message.items.len + message_len > CDP_MAX_MESSAGE_SIZE) {
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return error.TooLarge;
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}
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try fragments.message.appendSlice(self.allocator, payload);
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if (fin == false) {
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// maybe we have more parts of the message waiting
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continue :LOOP;
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}
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// this continuation is done!
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return .{
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.type = fragments.type,
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.data = fragments.message.items,
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.cleanup_fragment = true,
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};
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}
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const can_be_fragmented = message_type == .text or message_type == .binary;
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if (self.fragments != null and can_be_fragmented) {
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// if this isn't a continuation, then we can't have fragments
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return error.NestedFragementation;
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}
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if (fin == false) {
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if (can_be_fragmented == false) {
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return error.InvalidContinuation;
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}
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// not continuation, and not fin. It has to be the first message
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// in a fragmented message.
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var fragments = Fragments{ .message = .{}, .type = message_type };
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try fragments.message.appendSlice(self.allocator, payload);
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self.fragments = fragments;
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continue :LOOP;
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}
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return .{
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.data = payload,
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.type = message_type,
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.cleanup_fragment = false,
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};
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}
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}
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fn extractLengths(buf: []const u8) ?struct { usize, usize } {
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if (buf.len < 2) {
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return null;
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}
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const length_of_len: usize = switch (buf[1] & 127) {
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126 => 2,
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127 => 8,
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else => 0,
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};
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if (buf.len < length_of_len + 2) {
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// we definitely don't have enough buf yet
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return null;
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}
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const message_len = switch (length_of_len) {
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2 => @as(u16, @intCast(buf[3])) | @as(u16, @intCast(buf[2])) << 8,
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8 => @as(u64, @intCast(buf[9])) | @as(u64, @intCast(buf[8])) << 8 | @as(u64, @intCast(buf[7])) << 16 | @as(u64, @intCast(buf[6])) << 24 | @as(u64, @intCast(buf[5])) << 32 | @as(u64, @intCast(buf[4])) << 40 | @as(u64, @intCast(buf[3])) << 48 | @as(u64, @intCast(buf[2])) << 56,
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else => buf[1] & 127,
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} + length_of_len + 2 + if (comptime EXPECT_MASK) 4 else 0; // +2 for header prefix, +4 for mask;
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return .{ length_of_len, message_len };
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}
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// This is called after we've processed complete websocket messages (this
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// only applies to websocket messages).
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// There are three cases:
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// 1 - We don't have any incomplete data (for a subsequent message) in buf.
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// This is the easier to handle, we can set pos & len to 0.
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// 2 - We have part of the next message, but we know it'll fit in the
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// remaining buf. We don't need to do anything
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// 3 - We have part of the next message, but either it won't fight into the
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// remaining buffer, or we don't know (because we don't have enough
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// of the header to tell the length). We need to "compact" the buffer
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fn compact(self: *Self) void {
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const pos = self.pos;
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const len = self.len;
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assert(pos <= len, "Client.Reader.compact precondition", .{ .pos = pos, .len = len });
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// how many (if any) partial bytes do we have
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const partial_bytes = len - pos;
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if (partial_bytes == 0) {
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// We have no partial bytes. Setting these to 0 ensures that we
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// get the best utilization of our buffer
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self.pos = 0;
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self.len = 0;
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return;
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}
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const partial = self.buf[pos..len];
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// If we have enough bytes of the next message to tell its length
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// we'll be able to figure out whether we need to do anything or not.
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if (extractLengths(partial)) |length_meta| {
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const next_message_len = length_meta.@"1";
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// if this isn't true, then we have a full message and it
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// should have been processed.
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assert(pos <= len, "Client.Reader.compact postcondition", .{ .next_len = next_message_len, .partial = partial_bytes });
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const missing_bytes = next_message_len - partial_bytes;
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const free_space = self.buf.len - len;
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if (missing_bytes < free_space) {
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// we have enough space in our buffer, as is,
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return;
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}
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}
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// We're here because we either don't have enough bytes of the next
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// message, or we know that it won't fit in our buffer as-is.
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std.mem.copyForwards(u8, self.buf, partial);
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self.pos = 0;
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self.len = partial_bytes;
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}
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};
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}
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pub const WsConnection = struct {
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// CLOSE, 2 length, code
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const CLOSE_NORMAL = [_]u8{ 136, 2, 3, 232 }; // code: 1000
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const CLOSE_GOING_AWAY = [_]u8{ 136, 2, 3, 233 }; // code: 1001
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const CLOSE_TOO_BIG = [_]u8{ 136, 2, 3, 241 }; // 1009
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const CLOSE_PROTOCOL_ERROR = [_]u8{ 136, 2, 3, 234 }; //code: 1002
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// "private-use" close codes must be from 4000-49999
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const CLOSE_TIMEOUT = [_]u8{ 136, 2, 15, 160 }; // code: 4000
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socket: posix.socket_t,
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socket_flags: usize,
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reader: Reader(true),
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send_arena: ArenaAllocator,
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json_version_response: []const u8,
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timeout_ms: u32,
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pub fn init(socket: posix.socket_t, allocator: Allocator, json_version_response: []const u8, timeout_ms: u32) !WsConnection {
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const socket_flags = try posix.fcntl(socket, posix.F.GETFL, 0);
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const nonblocking = @as(u32, @bitCast(posix.O{ .NONBLOCK = true }));
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assert(socket_flags & nonblocking == nonblocking, "WsConnection.init blocking", .{});
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var reader = try Reader(true).init(allocator);
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errdefer reader.deinit();
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return .{
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.socket = socket,
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.socket_flags = socket_flags,
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.reader = reader,
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.send_arena = ArenaAllocator.init(allocator),
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.json_version_response = json_version_response,
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.timeout_ms = timeout_ms,
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};
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}
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pub fn deinit(self: *WsConnection) void {
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self.reader.deinit();
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self.send_arena.deinit();
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}
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pub fn send(self: *WsConnection, data: []const u8) !void {
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var pos: usize = 0;
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var changed_to_blocking: bool = false;
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defer _ = self.send_arena.reset(.{ .retain_with_limit = 1024 * 32 });
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defer if (changed_to_blocking) {
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// We had to change our socket to blocking me to get our write out
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// We need to change it back to non-blocking.
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_ = posix.fcntl(self.socket, posix.F.SETFL, self.socket_flags) catch |err| {
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log.err(.app, "ws restore nonblocking", .{ .err = err });
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};
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};
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LOOP: while (pos < data.len) {
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const written = posix.write(self.socket, data[pos..]) catch |err| switch (err) {
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error.WouldBlock => {
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// self.socket is nonblocking, because we don't want to block
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// reads. But our life is a lot easier if we block writes,
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// largely, because we don't have to maintain a queue of pending
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// writes (which would each need their own allocations). So
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// if we get a WouldBlock error, we'll switch the socket to
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// blocking and switch it back to non-blocking after the write
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// is complete. Doesn't seem particularly efficiently, but
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// this should virtually never happen.
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assert(changed_to_blocking == false, "WsConnection.double block", .{});
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changed_to_blocking = true;
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_ = try posix.fcntl(self.socket, posix.F.SETFL, self.socket_flags & ~@as(u32, @bitCast(posix.O{ .NONBLOCK = true })));
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continue :LOOP;
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},
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else => return err,
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};
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if (written == 0) {
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return error.Closed;
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}
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pos += written;
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}
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}
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const EMPTY_PONG = [_]u8{ 138, 0 };
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fn sendPong(self: *WsConnection, data: []const u8) !void {
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if (data.len == 0) {
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return self.send(&EMPTY_PONG);
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}
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var header_buf: [10]u8 = undefined;
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const header = websocketHeader(&header_buf, .pong, data.len);
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const allocator = self.send_arena.allocator();
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const framed = try allocator.alloc(u8, header.len + data.len);
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@memcpy(framed[0..header.len], header);
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@memcpy(framed[header.len..], data);
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return self.send(framed);
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}
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// called by CDP
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// Websocket frames have a variable length header. For server-client,
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// it could be anywhere from 2 to 10 bytes. Our IO.Loop doesn't have
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// writev, so we need to get creative. We'll JSON serialize to a
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// buffer, where the first 10 bytes are reserved. We can then backfill
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// the header and send the slice.
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pub fn sendJSON(self: *WsConnection, message: anytype, opts: std.json.Stringify.Options) !void {
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const allocator = self.send_arena.allocator();
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var aw = try std.Io.Writer.Allocating.initCapacity(allocator, 512);
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// reserve space for the maximum possible header
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try aw.writer.writeAll(&.{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 });
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try std.json.Stringify.value(message, opts, &aw.writer);
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const framed = fillWebsocketHeader(aw.toArrayList());
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return self.send(framed);
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}
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pub fn sendJSONRaw(
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self: *WsConnection,
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buf: std.ArrayList(u8),
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) !void {
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// Dangerous API!. We assume the caller has reserved the first 10
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// bytes in `buf`.
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const framed = fillWebsocketHeader(buf);
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return self.send(framed);
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}
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pub fn read(self: *WsConnection) !usize {
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const n = try posix.read(self.socket, self.reader.readBuf());
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self.reader.len += n;
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return n;
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}
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pub fn processMessages(self: *WsConnection, handler: anytype) !bool {
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var reader = &self.reader;
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while (true) {
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const msg = reader.next() catch |err| {
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switch (err) {
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error.TooLarge => self.send(&CLOSE_TOO_BIG) catch {},
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error.NotMasked => self.send(&CLOSE_PROTOCOL_ERROR) catch {},
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error.ReservedFlags => self.send(&CLOSE_PROTOCOL_ERROR) catch {},
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error.InvalidMessageType => self.send(&CLOSE_PROTOCOL_ERROR) catch {},
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error.ControlTooLarge => self.send(&CLOSE_PROTOCOL_ERROR) catch {},
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error.InvalidContinuation => self.send(&CLOSE_PROTOCOL_ERROR) catch {},
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error.NestedFragementation => self.send(&CLOSE_PROTOCOL_ERROR) catch {},
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error.OutOfMemory => {}, // don't borther trying to send an error in this case
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}
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return err;
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} orelse break;
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switch (msg.type) {
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.pong => {},
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.ping => try self.sendPong(msg.data),
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.close => {
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self.send(&CLOSE_NORMAL) catch {};
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return false;
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},
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.text, .binary => if (handler.handleMessage(msg.data) == false) {
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return false;
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},
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}
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if (msg.cleanup_fragment) {
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reader.cleanup();
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}
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}
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// We might have read part of the next message. Our reader potentially
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// has to move data around in its buffer to make space.
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reader.compact();
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return true;
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}
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pub fn upgrade(self: *WsConnection, request: []u8) !void {
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// our caller already confirmed that we have a trailing \r\n\r\n
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const request_line_end = std.mem.indexOfScalar(u8, request, '\r') orelse unreachable;
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const request_line = request[0..request_line_end];
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if (!std.ascii.endsWithIgnoreCase(request_line, "http/1.1")) {
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return error.InvalidProtocol;
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}
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// we need to extract the sec-websocket-key value
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var key: []const u8 = "";
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// we need to make sure that we got all the necessary headers + values
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var required_headers: u8 = 0;
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// can't std.mem.split because it forces the iterated value to be const
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// (we could @constCast...)
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var buf = request[request_line_end + 2 ..];
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|
|
while (buf.len > 4) {
|
|
const index = std.mem.indexOfScalar(u8, buf, '\r') orelse unreachable;
|
|
const separator = std.mem.indexOfScalar(u8, buf[0..index], ':') orelse return error.InvalidRequest;
|
|
|
|
const name = std.mem.trim(u8, toLower(buf[0..separator]), &std.ascii.whitespace);
|
|
const value = std.mem.trim(u8, buf[(separator + 1)..index], &std.ascii.whitespace);
|
|
|
|
if (std.mem.eql(u8, name, "upgrade")) {
|
|
if (!std.ascii.eqlIgnoreCase("websocket", value)) {
|
|
return error.InvalidUpgradeHeader;
|
|
}
|
|
required_headers |= 1;
|
|
} else if (std.mem.eql(u8, name, "sec-websocket-version")) {
|
|
if (value.len != 2 or value[0] != '1' or value[1] != '3') {
|
|
return error.InvalidVersionHeader;
|
|
}
|
|
required_headers |= 2;
|
|
} else if (std.mem.eql(u8, name, "connection")) {
|
|
// find if connection header has upgrade in it, example header:
|
|
// Connection: keep-alive, Upgrade
|
|
if (std.ascii.indexOfIgnoreCase(value, "upgrade") == null) {
|
|
return error.InvalidConnectionHeader;
|
|
}
|
|
required_headers |= 4;
|
|
} else if (std.mem.eql(u8, name, "sec-websocket-key")) {
|
|
key = value;
|
|
required_headers |= 8;
|
|
}
|
|
|
|
const next = index + 2;
|
|
buf = buf[next..];
|
|
}
|
|
|
|
if (required_headers != 15) {
|
|
return error.MissingHeaders;
|
|
}
|
|
|
|
// our caller has already made sure this request ended in \r\n\r\n
|
|
// so it isn't something we need to check again
|
|
|
|
const alloc = self.send_arena.allocator();
|
|
|
|
const response = blk: {
|
|
// Response to an ugprade request is always this, with
|
|
// the Sec-Websocket-Accept value a spacial sha1 hash of the
|
|
// request "sec-websocket-version" and a magic value.
|
|
|
|
const template =
|
|
"HTTP/1.1 101 Switching Protocols\r\n" ++
|
|
"Upgrade: websocket\r\n" ++
|
|
"Connection: upgrade\r\n" ++
|
|
"Sec-Websocket-Accept: 0000000000000000000000000000\r\n\r\n";
|
|
|
|
// The response will be sent via the IO Loop and thus has to have its
|
|
// own lifetime.
|
|
const res = try alloc.dupe(u8, template);
|
|
|
|
// magic response
|
|
const key_pos = res.len - 32;
|
|
var h: [20]u8 = undefined;
|
|
var hasher = std.crypto.hash.Sha1.init(.{});
|
|
hasher.update(key);
|
|
// websocket spec always used this value
|
|
hasher.update("258EAFA5-E914-47DA-95CA-C5AB0DC85B11");
|
|
hasher.final(&h);
|
|
|
|
_ = std.base64.standard.Encoder.encode(res[key_pos .. key_pos + 28], h[0..]);
|
|
|
|
break :blk res;
|
|
};
|
|
|
|
return self.send(response);
|
|
}
|
|
|
|
pub fn sendHttpError(self: *WsConnection, comptime status: u16, comptime body: []const u8) void {
|
|
const response = std.fmt.comptimePrint(
|
|
"HTTP/1.1 {d} \r\nConnection: Close\r\nContent-Length: {d}\r\n\r\n{s}",
|
|
.{ status, body.len, body },
|
|
);
|
|
|
|
// we're going to close this connection anyways, swallowing any
|
|
// error seems safe
|
|
self.send(response) catch {};
|
|
}
|
|
|
|
pub fn getAddress(self: *WsConnection) !std.net.Address {
|
|
var address: std.net.Address = undefined;
|
|
var socklen: posix.socklen_t = @sizeOf(std.net.Address);
|
|
try posix.getpeername(self.socket, &address.any, &socklen);
|
|
return address;
|
|
}
|
|
|
|
pub fn sendClose(self: *WsConnection) void {
|
|
self.send(&CLOSE_GOING_AWAY) catch {};
|
|
}
|
|
|
|
pub fn shutdown(self: *WsConnection) void {
|
|
posix.shutdown(self.socket, .recv) catch {};
|
|
}
|
|
|
|
pub fn setBlocking(self: *WsConnection, blocking: bool) !void {
|
|
if (blocking) {
|
|
_ = try posix.fcntl(self.socket, posix.F.SETFL, self.socket_flags & ~@as(u32, @bitCast(posix.O{ .NONBLOCK = true })));
|
|
} else {
|
|
_ = try posix.fcntl(self.socket, posix.F.SETFL, self.socket_flags);
|
|
}
|
|
}
|
|
};
|
|
|
|
fn fillWebsocketHeader(buf: std.ArrayList(u8)) []const u8 {
|
|
// can't use buf[0..10] here, because the header length
|
|
// is variable. If it's just 2 bytes, for example, we need the
|
|
// framed message to be:
|
|
// h1, h2, data
|
|
// If we use buf[0..10], we'd get:
|
|
// h1, h2, 0, 0, 0, 0, 0, 0, 0, 0, data
|
|
|
|
var header_buf: [10]u8 = undefined;
|
|
|
|
// -10 because we reserved 10 bytes for the header above
|
|
const header = websocketHeader(&header_buf, .text, buf.items.len - 10);
|
|
const start = 10 - header.len;
|
|
|
|
const message = buf.items;
|
|
@memcpy(message[start..10], header);
|
|
return message[start..];
|
|
}
|
|
|
|
// makes the assumption that our caller reserved the first
|
|
// 10 bytes for the header
|
|
fn websocketHeader(buf: []u8, op_code: OpCode, payload_len: usize) []const u8 {
|
|
assert(buf.len == 10, "Websocket.Header", .{ .len = buf.len });
|
|
|
|
const len = payload_len;
|
|
buf[0] = 128 | @intFromEnum(op_code); // fin | opcode
|
|
|
|
if (len <= 125) {
|
|
buf[1] = @intCast(len);
|
|
return buf[0..2];
|
|
}
|
|
|
|
if (len < 65536) {
|
|
buf[1] = 126;
|
|
buf[2] = @intCast((len >> 8) & 0xFF);
|
|
buf[3] = @intCast(len & 0xFF);
|
|
return buf[0..4];
|
|
}
|
|
|
|
buf[1] = 127;
|
|
buf[2] = 0;
|
|
buf[3] = 0;
|
|
buf[4] = 0;
|
|
buf[5] = 0;
|
|
buf[6] = @intCast((len >> 24) & 0xFF);
|
|
buf[7] = @intCast((len >> 16) & 0xFF);
|
|
buf[8] = @intCast((len >> 8) & 0xFF);
|
|
buf[9] = @intCast(len & 0xFF);
|
|
return buf[0..10];
|
|
}
|
|
|
|
fn growBuffer(allocator: Allocator, buf: []u8, required_capacity: usize) ![]u8 {
|
|
// from std.ArrayList
|
|
var new_capacity = buf.len;
|
|
while (true) {
|
|
new_capacity +|= new_capacity / 2 + 8;
|
|
if (new_capacity >= required_capacity) break;
|
|
}
|
|
|
|
log.debug(.app, "CDP buffer growth", .{ .from = buf.len, .to = new_capacity });
|
|
|
|
if (allocator.resize(buf, new_capacity)) {
|
|
return buf.ptr[0..new_capacity];
|
|
}
|
|
const new_buffer = try allocator.alloc(u8, new_capacity);
|
|
@memcpy(new_buffer[0..buf.len], buf);
|
|
allocator.free(buf);
|
|
return new_buffer;
|
|
}
|
|
|
|
// In-place string lowercase
|
|
fn toLower(str: []u8) []u8 {
|
|
for (str, 0..) |ch, i| {
|
|
str[i] = std.ascii.toLower(ch);
|
|
}
|
|
return str;
|
|
}
|
|
|
|
// Used when SIMD isn't available, or for any remaining part of the message
|
|
// which is too small to effectively use SIMD.
|
|
fn simpleMask(m: []const u8, payload: []u8) void {
|
|
for (payload, 0..) |b, i| {
|
|
payload[i] = b ^ m[i & 3];
|
|
}
|
|
}
|
|
|
|
// Zig is in a weird backend transition right now. Need to determine if
|
|
// SIMD is even available.
|
|
const backend_supports_vectors = switch (builtin.zig_backend) {
|
|
.stage2_llvm, .stage2_c => true,
|
|
else => false,
|
|
};
|
|
|
|
// Websocket messages from client->server are masked using a 4 byte XOR mask
|
|
fn mask(m: []const u8, payload: []u8) void {
|
|
var data = payload;
|
|
|
|
if (!comptime backend_supports_vectors) return simpleMask(m, data);
|
|
|
|
const vector_size = std.simd.suggestVectorLength(u8) orelse @sizeOf(usize);
|
|
if (data.len >= vector_size) {
|
|
const mask_vector = std.simd.repeat(vector_size, @as(@Vector(4, u8), m[0..4].*));
|
|
while (data.len >= vector_size) {
|
|
const slice = data[0..vector_size];
|
|
const masked_data_slice: @Vector(vector_size, u8) = slice.*;
|
|
slice.* = masked_data_slice ^ mask_vector;
|
|
data = data[vector_size..];
|
|
}
|
|
}
|
|
simpleMask(m, data);
|
|
}
|
|
|
|
const testing = std.testing;
|
|
|
|
test "mask" {
|
|
var buf: [4000]u8 = undefined;
|
|
const messages = [_][]const u8{ "1234", "1234" ** 99, "1234" ** 999 };
|
|
for (messages) |message| {
|
|
// we need the message to be mutable since mask operates in-place
|
|
const payload = buf[0..message.len];
|
|
@memcpy(payload, message);
|
|
|
|
mask(&.{ 1, 2, 200, 240 }, payload);
|
|
try testing.expectEqual(false, std.mem.eql(u8, payload, message));
|
|
|
|
mask(&.{ 1, 2, 200, 240 }, payload);
|
|
try testing.expectEqual(true, std.mem.eql(u8, payload, message));
|
|
}
|
|
}
|