mirror of
https://github.com/mandiant/gopacket
synced 2026-06-21 13:57:02 +00:00
Jacob Paullus
108 lines
2.6 KiB
Go
108 lines
2.6 KiB
Go
// Copyright 2026 Google LLC
|
|
//
|
|
// 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
|
|
//
|
|
// https://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 dcerpc
|
|
|
|
import (
|
|
"encoding/hex"
|
|
"fmt"
|
|
"strings"
|
|
)
|
|
|
|
// ParseUUID parses a UUID string like "000001A0-0000-0000-C000-000000000046" to [16]byte.
|
|
// The UUID is stored in the DCE/RPC wire format (Data1 little-endian, Data2/Data3 little-endian).
|
|
func ParseUUID(s string) ([16]byte, error) {
|
|
var result [16]byte
|
|
|
|
// Remove dashes
|
|
s = strings.ReplaceAll(s, "-", "")
|
|
s = strings.ToLower(s)
|
|
|
|
if len(s) != 32 {
|
|
return result, fmt.Errorf("invalid UUID length: %d", len(s))
|
|
}
|
|
|
|
// Decode hex string
|
|
data, err := hex.DecodeString(s)
|
|
if err != nil {
|
|
return result, fmt.Errorf("invalid UUID hex: %v", err)
|
|
}
|
|
|
|
// UUID structure in memory/wire format:
|
|
// Data1: 4 bytes, little-endian (reversed from string)
|
|
// Data2: 2 bytes, little-endian (reversed from string)
|
|
// Data3: 2 bytes, little-endian (reversed from string)
|
|
// Data4: 8 bytes, big-endian (as-is)
|
|
|
|
// Data1 (bytes 0-3 in string): reverse
|
|
result[0] = data[3]
|
|
result[1] = data[2]
|
|
result[2] = data[1]
|
|
result[3] = data[0]
|
|
|
|
// Data2 (bytes 4-5 in string): reverse
|
|
result[4] = data[5]
|
|
result[5] = data[4]
|
|
|
|
// Data3 (bytes 6-7 in string): reverse
|
|
result[6] = data[7]
|
|
result[7] = data[6]
|
|
|
|
// Data4 (bytes 8-15 in string): as-is
|
|
copy(result[8:], data[8:])
|
|
|
|
return result, nil
|
|
}
|
|
|
|
// MustParseUUID parses a UUID string and panics on error.
|
|
// Use this for compile-time constants.
|
|
func MustParseUUID(s string) [16]byte {
|
|
result, err := ParseUUID(s)
|
|
if err != nil {
|
|
panic(fmt.Sprintf("invalid UUID %q: %v", s, err))
|
|
}
|
|
return result
|
|
}
|
|
|
|
// FormatUUID formats a [16]byte UUID as a string like "000001a0-0000-0000-c000-000000000046"
|
|
func FormatUUID(uuid [16]byte) string {
|
|
// Reverse the byte order for display
|
|
data := make([]byte, 16)
|
|
|
|
// Data1: reverse
|
|
data[0] = uuid[3]
|
|
data[1] = uuid[2]
|
|
data[2] = uuid[1]
|
|
data[3] = uuid[0]
|
|
|
|
// Data2: reverse
|
|
data[4] = uuid[5]
|
|
data[5] = uuid[4]
|
|
|
|
// Data3: reverse
|
|
data[6] = uuid[7]
|
|
data[7] = uuid[6]
|
|
|
|
// Data4: as-is
|
|
copy(data[8:], uuid[8:])
|
|
|
|
return fmt.Sprintf("%08x-%04x-%04x-%04x-%012x",
|
|
data[0:4],
|
|
data[4:6],
|
|
data[6:8],
|
|
data[8:10],
|
|
data[10:16],
|
|
)
|
|
}
|