| // Copyright 2016 The Netstack 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 fragmentation |
| |
| import ( |
| "reflect" |
| "testing" |
| "time" |
| |
| "github.com/google/netstack/tcpip/buffer" |
| ) |
| |
| // vv is a helper to build VectorisedView from different strings. |
| func vv(size int, pieces ...string) *buffer.VectorisedView { |
| views := make([]buffer.View, len(pieces)) |
| for i, p := range pieces { |
| views[i] = []byte(p) |
| } |
| |
| vv := buffer.NewVectorisedView(size, views) |
| return &vv |
| } |
| |
| func emptyVv() *buffer.VectorisedView { |
| vv := buffer.NewVectorisedView(0, nil) |
| return &vv |
| } |
| |
| type processInput struct { |
| id uint32 |
| first uint16 |
| last uint16 |
| more bool |
| vv *buffer.VectorisedView |
| } |
| |
| type processOutput struct { |
| vv *buffer.VectorisedView |
| done bool |
| } |
| |
| var processTestCases = []struct { |
| comment string |
| in []processInput |
| out []processOutput |
| }{ |
| { |
| comment: "One ID", |
| in: []processInput{ |
| {id: 0, first: 0, last: 1, more: true, vv: vv(2, "01")}, |
| {id: 0, first: 2, last: 3, more: false, vv: vv(2, "23")}, |
| }, |
| out: []processOutput{ |
| {vv: emptyVv(), done: false}, |
| {vv: vv(4, "01", "23"), done: true}, |
| }, |
| }, |
| { |
| comment: "Two IDs", |
| in: []processInput{ |
| {id: 0, first: 0, last: 1, more: true, vv: vv(2, "01")}, |
| {id: 1, first: 0, last: 1, more: true, vv: vv(2, "ab")}, |
| {id: 1, first: 2, last: 3, more: false, vv: vv(2, "cd")}, |
| {id: 0, first: 2, last: 3, more: false, vv: vv(2, "23")}, |
| }, |
| out: []processOutput{ |
| {vv: emptyVv(), done: false}, |
| {vv: emptyVv(), done: false}, |
| {vv: vv(4, "ab", "cd"), done: true}, |
| {vv: vv(4, "01", "23"), done: true}, |
| }, |
| }, |
| } |
| |
| func TestFragmentationProcess(t *testing.T) { |
| for _, c := range processTestCases { |
| f := NewFragmentation(1024, DefaultReassembleTimeout) |
| for i, in := range c.in { |
| vv, done := f.Process(in.id, in.first, in.last, in.more, in.vv) |
| if !reflect.DeepEqual(vv, *(c.out[i].vv)) { |
| t.Errorf("Test \"%s\" Process() returned a wrong vv. Got %v. Want %v", c.comment, vv, *(c.out[i].vv)) |
| } |
| if done != c.out[i].done { |
| t.Errorf("Test \"%s\" Process() returned a wrong done. Got %t. Want %t", c.comment, done, c.out[i].done) |
| } |
| } |
| } |
| } |
| |
| func TestReassemblingTimeout(t *testing.T) { |
| timeout := time.Millisecond |
| f := NewFragmentation(1024, timeout) |
| // Send first fragment with id = 0, first = 0, last = 0, and more = true. |
| f.Process(0, 0, 0, true, vv(1, "0")) |
| // Sleep more than the timeout. |
| time.Sleep(2 * timeout) |
| // Send another fragment that completes a packet. |
| // However, no packet should be reassembled because the fragment arrived after the timeout. |
| _, done := f.Process(0, 1, 1, false, vv(1, "1")) |
| if done { |
| t.Errorf("Fragmentation does not respect the reassembling timeout.") |
| } |
| } |
| |
| func TestMemoryLimits(t *testing.T) { |
| f := NewFragmentation(1, DefaultReassembleTimeout) |
| // Send first fragment with id = 0. |
| f.Process(0, 0, 0, true, vv(1, "0")) |
| // Send first fragment with id = 1. This should caused id = 0 to be evicted. |
| f.Process(1, 0, 0, true, vv(1, "0")) |
| |
| if _, ok := f.reassemblers[0]; ok { |
| t.Errorf("Memory limits are not respected: id=0 has not been evicted.") |
| } |
| if _, ok := f.reassemblers[1]; !ok { |
| t.Errorf("Implementation of memory limits is wrong: id=1 is not present.") |
| } |
| } |
| |
| func TestMemoryLimitsIgnoresDuplicates(t *testing.T) { |
| f := NewFragmentation(1, DefaultReassembleTimeout) |
| // Send first fragment with id = 0. |
| f.Process(0, 0, 0, true, vv(1, "0")) |
| // Send the same packet again. |
| f.Process(0, 0, 0, true, vv(1, "0")) |
| |
| got := f.size |
| want := 1 |
| if got != want { |
| t.Errorf("Wrong size, duplicates are not handled correctly: got=%d, want=%d.", got, want) |
| } |
| } |
| |
| func TestFragmentationViewsDoNotEscape(t *testing.T) { |
| f := NewFragmentation(1024, DefaultReassembleTimeout) |
| in := vv(2, "0", "1") |
| f.Process(0, 0, 1, true, in) |
| // Modify input view. |
| in.RemoveFirst() |
| got, _ := f.Process(0, 2, 2, false, vv(1, "2")) |
| want := vv(3, "0", "1", "2") |
| if !reflect.DeepEqual(got, *want) { |
| t.Errorf("Process() returned a wrong vv. Got %v. Want %v", got, *want) |
| } |
| } |