1 files changed, 45 insertions, 0 deletions
diff --git a/src/vendor/golang.org/x/net/quic/udp_darwin.go b/src/vendor/golang.org/x/net/quic/udp_darwin.go
new file mode 100644
index 0000000000..91e8e81c17
--- /dev/null
+++ b/src/vendor/golang.org/x/net/quic/udp_darwin.go
@@ -0,0 +1,45 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build darwin
+
+package quic
+
+import (
+	"encoding/binary"
+	"syscall"
+)
+
+// These socket options are available on darwin, but are not in the syscall
+// package. Since syscall package is frozen, just define them manually here.
+const (
+	ip_recvtos       = 0x1b
+	ipv6_recvpktinfo = 0x3d
+	ipv6_pktinfo     = 0x2e
+)
+
+// See udp.go.
+const (
+	udpECNSupport              = true
+	udpInvalidLocalAddrIsError = true
+)
+
+// Confusingly, on Darwin the contents of the IP_TOS option differ depending on whether
+// it is used as an inbound or outbound cmsg.
+
+func parseIPTOS(b []byte) (ecnBits, bool) {
+	// Single byte. The low two bits are the ECN field.
+	if len(b) != 1 {
+		return 0, false
+	}
+	return ecnBits(b[0] & ecnMask), true
+}
+
+func appendCmsgECNv4(b []byte, ecn ecnBits) []byte {
+	// 32-bit integer.
+	// https://github.com/apple/darwin-xnu/blob/2ff845c2e033bd0ff64b5b6aa6063a1f8f65aa32/bsd/netinet/in_tclass.c#L1062-L1073
+	b, data := appendCmsg(b, syscall.IPPROTO_IP, syscall.IP_TOS, 4)
+	binary.NativeEndian.PutUint32(data, uint32(ecn))
+	return b
+}