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|
package ber
import (
"bytes"
"io"
"math"
"testing"
)
func TestReadLength(t *testing.T) {
testcases := map[string]struct {
Data []byte
ExpectedLength int
ExpectedBytesRead int
ExpectedError string
}{
"empty": {
Data: []byte{},
ExpectedBytesRead: 0,
ExpectedError: io.ErrUnexpectedEOF.Error(),
},
"invalid first byte": {
Data: []byte{0xFF},
ExpectedBytesRead: 1,
ExpectedError: "invalid length byte 0xff",
},
"indefinite form": {
Data: []byte{LengthLongFormBitmask},
ExpectedLength: LengthIndefinite,
ExpectedBytesRead: 1,
},
"short-definite-form zero length": {
Data: []byte{0},
ExpectedLength: 0,
ExpectedBytesRead: 1,
},
"short-definite-form length 1": {
Data: []byte{1},
ExpectedLength: 1,
ExpectedBytesRead: 1,
},
"short-definite-form max length": {
Data: []byte{127},
ExpectedLength: 127,
ExpectedBytesRead: 1,
},
"long-definite-form missing bytes": {
Data: []byte{LengthLongFormBitmask | 1},
ExpectedBytesRead: 1,
ExpectedError: io.ErrUnexpectedEOF.Error(),
},
"long-definite-form overflow": {
Data: []byte{LengthLongFormBitmask | 9},
ExpectedBytesRead: 1,
ExpectedError: "long-form length overflow",
},
"long-definite-form zero length": {
Data: []byte{LengthLongFormBitmask | 1, 0x0},
ExpectedLength: 0,
ExpectedBytesRead: 2,
},
"long-definite-form length 127": {
Data: []byte{LengthLongFormBitmask | 1, 127},
ExpectedLength: 127,
ExpectedBytesRead: 2,
},
"long-definite-form max length": {
Data: []byte{
LengthLongFormBitmask | 8,
0x7F,
0xFF,
0xFF,
0xFF,
0xFF,
0xFF,
0xFF,
0xFF,
},
ExpectedLength: math.MaxInt64,
ExpectedBytesRead: 9,
},
}
for k, tc := range testcases {
reader := bytes.NewBuffer(tc.Data)
length, read, err := readLength(reader)
if err != nil {
if tc.ExpectedError == "" {
t.Errorf("%s: unexpected error: %v", k, err)
} else if err.Error() != tc.ExpectedError {
t.Errorf("%s: expected error %v, got %v", k, tc.ExpectedError, err)
}
} else if tc.ExpectedError != "" {
t.Errorf("%s: expected error %v, got none", k, tc.ExpectedError)
continue
}
if read != tc.ExpectedBytesRead {
t.Errorf("%s: expected read %d, got %d", k, tc.ExpectedBytesRead, read)
}
if length != tc.ExpectedLength {
t.Errorf("%s: expected length %d, got %d", k, tc.ExpectedLength, length)
}
}
}
func TestEncodeLength(t *testing.T) {
testcases := map[string]struct {
Length int
ExpectedBytes []byte
}{
"0": {
Length: 0,
ExpectedBytes: []byte{0},
},
"1": {
Length: 1,
ExpectedBytes: []byte{1},
},
"max short-form length": {
Length: 127,
ExpectedBytes: []byte{127},
},
"min long-form length": {
Length: 128,
ExpectedBytes: []byte{LengthLongFormBitmask | 1, 128},
},
"max long-form length": {
Length: math.MaxInt64,
ExpectedBytes: []byte{
LengthLongFormBitmask | 8,
0x7F,
0xFF,
0xFF,
0xFF,
0xFF,
0xFF,
0xFF,
0xFF,
},
},
}
for k, tc := range testcases {
b := encodeLength(tc.Length)
if bytes.Compare(tc.ExpectedBytes, b) != 0 {
t.Errorf("%s: Expected\n\t%#v\ngot\n\t%#v", k, tc.ExpectedBytes, b)
}
}
}
|
