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Diffstat (limited to 'vendor/golang.org/x/net/ipv4/bpf_test.go')
-rw-r--r--vendor/golang.org/x/net/ipv4/bpf_test.go93
1 files changed, 93 insertions, 0 deletions
diff --git a/vendor/golang.org/x/net/ipv4/bpf_test.go b/vendor/golang.org/x/net/ipv4/bpf_test.go
new file mode 100644
index 0000000..b44da90
--- /dev/null
+++ b/vendor/golang.org/x/net/ipv4/bpf_test.go
@@ -0,0 +1,93 @@
+// Copyright 2016 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.
+
+package ipv4_test
+
+import (
+ "net"
+ "runtime"
+ "testing"
+ "time"
+
+ "golang.org/x/net/bpf"
+ "golang.org/x/net/ipv4"
+)
+
+func TestBPF(t *testing.T) {
+ if runtime.GOOS != "linux" {
+ t.Skipf("not supported on %s", runtime.GOOS)
+ }
+
+ l, err := net.ListenPacket("udp4", "127.0.0.1:0")
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer l.Close()
+
+ p := ipv4.NewPacketConn(l)
+
+ // This filter accepts UDP packets whose first payload byte is
+ // even.
+ prog, err := bpf.Assemble([]bpf.Instruction{
+ // Load the first byte of the payload (skipping UDP header).
+ bpf.LoadAbsolute{Off: 8, Size: 1},
+ // Select LSB of the byte.
+ bpf.ALUOpConstant{Op: bpf.ALUOpAnd, Val: 1},
+ // Byte is even?
+ bpf.JumpIf{Cond: bpf.JumpEqual, Val: 0, SkipFalse: 1},
+ // Accept.
+ bpf.RetConstant{Val: 4096},
+ // Ignore.
+ bpf.RetConstant{Val: 0},
+ })
+ if err != nil {
+ t.Fatalf("compiling BPF: %s", err)
+ }
+
+ if err = p.SetBPF(prog); err != nil {
+ t.Fatalf("attaching filter to Conn: %s", err)
+ }
+
+ s, err := net.Dial("udp4", l.LocalAddr().String())
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer s.Close()
+ go func() {
+ for i := byte(0); i < 10; i++ {
+ s.Write([]byte{i})
+ }
+ }()
+
+ l.SetDeadline(time.Now().Add(2 * time.Second))
+ seen := make([]bool, 5)
+ for {
+ var b [512]byte
+ n, _, err := l.ReadFrom(b[:])
+ if err != nil {
+ t.Fatalf("reading from listener: %s", err)
+ }
+ if n != 1 {
+ t.Fatalf("unexpected packet length, want 1, got %d", n)
+ }
+ if b[0] >= 10 {
+ t.Fatalf("unexpected byte, want 0-9, got %d", b[0])
+ }
+ if b[0]%2 != 0 {
+ t.Fatalf("got odd byte %d, wanted only even bytes", b[0])
+ }
+ seen[b[0]/2] = true
+
+ seenAll := true
+ for _, v := range seen {
+ if !v {
+ seenAll = false
+ break
+ }
+ }
+ if seenAll {
+ break
+ }
+ }
+}