| // Copyright 2018 Google Inc. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package fragmentation |
| |
| import ( |
| "container/heap" |
| "reflect" |
| "testing" |
| |
| "github.com/google/netstack/tcpip/buffer" |
| ) |
| |
| var reassambleTestCases = []struct { |
| comment string |
| in []fragment |
| want buffer.VectorisedView |
| }{ |
| { |
| comment: "Non-overlapping in-order", |
| in: []fragment{ |
| {offset: 0, vv: vv(1, "0")}, |
| {offset: 1, vv: vv(1, "1")}, |
| }, |
| want: vv(2, "0", "1"), |
| }, |
| { |
| comment: "Non-overlapping out-of-order", |
| in: []fragment{ |
| {offset: 1, vv: vv(1, "1")}, |
| {offset: 0, vv: vv(1, "0")}, |
| }, |
| want: vv(2, "0", "1"), |
| }, |
| { |
| comment: "Duplicated packets", |
| in: []fragment{ |
| {offset: 0, vv: vv(1, "0")}, |
| {offset: 0, vv: vv(1, "0")}, |
| }, |
| want: vv(1, "0"), |
| }, |
| { |
| comment: "Overlapping in-order", |
| in: []fragment{ |
| {offset: 0, vv: vv(2, "01")}, |
| {offset: 1, vv: vv(2, "12")}, |
| }, |
| want: vv(3, "01", "2"), |
| }, |
| { |
| comment: "Overlapping out-of-order", |
| in: []fragment{ |
| {offset: 1, vv: vv(2, "12")}, |
| {offset: 0, vv: vv(2, "01")}, |
| }, |
| want: vv(3, "01", "2"), |
| }, |
| { |
| comment: "Overlapping subset in-order", |
| in: []fragment{ |
| {offset: 0, vv: vv(3, "012")}, |
| {offset: 1, vv: vv(1, "1")}, |
| }, |
| want: vv(3, "012"), |
| }, |
| { |
| comment: "Overlapping subset out-of-order", |
| in: []fragment{ |
| {offset: 1, vv: vv(1, "1")}, |
| {offset: 0, vv: vv(3, "012")}, |
| }, |
| want: vv(3, "012"), |
| }, |
| } |
| |
| func TestReassamble(t *testing.T) { |
| for _, c := range reassambleTestCases { |
| t.Run(c.comment, func(t *testing.T) { |
| h := make(fragHeap, 0, 8) |
| heap.Init(&h) |
| for _, f := range c.in { |
| heap.Push(&h, f) |
| } |
| got, err := h.reassemble() |
| if err != nil { |
| t.Fatal(err) |
| } |
| if !reflect.DeepEqual(got, c.want) { |
| t.Errorf("got reassemble(%+v) = %v, want = %v", c.in, got, c.want) |
| } |
| }) |
| } |
| } |
| |
| func TestReassambleFailsForNonZeroOffset(t *testing.T) { |
| h := make(fragHeap, 0, 8) |
| heap.Init(&h) |
| heap.Push(&h, fragment{offset: 1, vv: vv(1, "0")}) |
| _, err := h.reassemble() |
| if err == nil { |
| t.Errorf("reassemble() did not fail when the first packet had offset != 0") |
| } |
| } |
| |
| func TestReassambleFailsForHoles(t *testing.T) { |
| h := make(fragHeap, 0, 8) |
| heap.Init(&h) |
| heap.Push(&h, fragment{offset: 0, vv: vv(1, "0")}) |
| heap.Push(&h, fragment{offset: 2, vv: vv(1, "1")}) |
| _, err := h.reassemble() |
| if err == nil { |
| t.Errorf("reassemble() did not fail when there was a hole in the packet") |
| } |
| } |