diff options
Diffstat (limited to 'vendor/github.com/Microsoft/go-winio/ea.go')
-rw-r--r-- | vendor/github.com/Microsoft/go-winio/ea.go | 274 |
1 files changed, 137 insertions, 137 deletions
diff --git a/vendor/github.com/Microsoft/go-winio/ea.go b/vendor/github.com/Microsoft/go-winio/ea.go index b37e930d6..4051c1b33 100644 --- a/vendor/github.com/Microsoft/go-winio/ea.go +++ b/vendor/github.com/Microsoft/go-winio/ea.go @@ -1,137 +1,137 @@ -package winio
-
-import (
- "bytes"
- "encoding/binary"
- "errors"
-)
-
-type fileFullEaInformation struct {
- NextEntryOffset uint32
- Flags uint8
- NameLength uint8
- ValueLength uint16
-}
-
-var (
- fileFullEaInformationSize = binary.Size(&fileFullEaInformation{})
-
- errInvalidEaBuffer = errors.New("invalid extended attribute buffer")
- errEaNameTooLarge = errors.New("extended attribute name too large")
- errEaValueTooLarge = errors.New("extended attribute value too large")
-)
-
-// ExtendedAttribute represents a single Windows EA.
-type ExtendedAttribute struct {
- Name string
- Value []byte
- Flags uint8
-}
-
-func parseEa(b []byte) (ea ExtendedAttribute, nb []byte, err error) {
- var info fileFullEaInformation
- err = binary.Read(bytes.NewReader(b), binary.LittleEndian, &info)
- if err != nil {
- err = errInvalidEaBuffer
- return
- }
-
- nameOffset := fileFullEaInformationSize
- nameLen := int(info.NameLength)
- valueOffset := nameOffset + int(info.NameLength) + 1
- valueLen := int(info.ValueLength)
- nextOffset := int(info.NextEntryOffset)
- if valueLen+valueOffset > len(b) || nextOffset < 0 || nextOffset > len(b) {
- err = errInvalidEaBuffer
- return
- }
-
- ea.Name = string(b[nameOffset : nameOffset+nameLen])
- ea.Value = b[valueOffset : valueOffset+valueLen]
- ea.Flags = info.Flags
- if info.NextEntryOffset != 0 {
- nb = b[info.NextEntryOffset:]
- }
- return
-}
-
-// DecodeExtendedAttributes decodes a list of EAs from a FILE_FULL_EA_INFORMATION
-// buffer retrieved from BackupRead, ZwQueryEaFile, etc.
-func DecodeExtendedAttributes(b []byte) (eas []ExtendedAttribute, err error) {
- for len(b) != 0 {
- ea, nb, err := parseEa(b)
- if err != nil {
- return nil, err
- }
-
- eas = append(eas, ea)
- b = nb
- }
- return
-}
-
-func writeEa(buf *bytes.Buffer, ea *ExtendedAttribute, last bool) error {
- if int(uint8(len(ea.Name))) != len(ea.Name) {
- return errEaNameTooLarge
- }
- if int(uint16(len(ea.Value))) != len(ea.Value) {
- return errEaValueTooLarge
- }
- entrySize := uint32(fileFullEaInformationSize + len(ea.Name) + 1 + len(ea.Value))
- withPadding := (entrySize + 3) &^ 3
- nextOffset := uint32(0)
- if !last {
- nextOffset = withPadding
- }
- info := fileFullEaInformation{
- NextEntryOffset: nextOffset,
- Flags: ea.Flags,
- NameLength: uint8(len(ea.Name)),
- ValueLength: uint16(len(ea.Value)),
- }
-
- err := binary.Write(buf, binary.LittleEndian, &info)
- if err != nil {
- return err
- }
-
- _, err = buf.Write([]byte(ea.Name))
- if err != nil {
- return err
- }
-
- err = buf.WriteByte(0)
- if err != nil {
- return err
- }
-
- _, err = buf.Write(ea.Value)
- if err != nil {
- return err
- }
-
- _, err = buf.Write([]byte{0, 0, 0}[0 : withPadding-entrySize])
- if err != nil {
- return err
- }
-
- return nil
-}
-
-// EncodeExtendedAttributes encodes a list of EAs into a FILE_FULL_EA_INFORMATION
-// buffer for use with BackupWrite, ZwSetEaFile, etc.
-func EncodeExtendedAttributes(eas []ExtendedAttribute) ([]byte, error) {
- var buf bytes.Buffer
- for i := range eas {
- last := false
- if i == len(eas)-1 {
- last = true
- }
-
- err := writeEa(&buf, &eas[i], last)
- if err != nil {
- return nil, err
- }
- }
- return buf.Bytes(), nil
-}
+package winio + +import ( + "bytes" + "encoding/binary" + "errors" +) + +type fileFullEaInformation struct { + NextEntryOffset uint32 + Flags uint8 + NameLength uint8 + ValueLength uint16 +} + +var ( + fileFullEaInformationSize = binary.Size(&fileFullEaInformation{}) + + errInvalidEaBuffer = errors.New("invalid extended attribute buffer") + errEaNameTooLarge = errors.New("extended attribute name too large") + errEaValueTooLarge = errors.New("extended attribute value too large") +) + +// ExtendedAttribute represents a single Windows EA. +type ExtendedAttribute struct { + Name string + Value []byte + Flags uint8 +} + +func parseEa(b []byte) (ea ExtendedAttribute, nb []byte, err error) { + var info fileFullEaInformation + err = binary.Read(bytes.NewReader(b), binary.LittleEndian, &info) + if err != nil { + err = errInvalidEaBuffer + return + } + + nameOffset := fileFullEaInformationSize + nameLen := int(info.NameLength) + valueOffset := nameOffset + int(info.NameLength) + 1 + valueLen := int(info.ValueLength) + nextOffset := int(info.NextEntryOffset) + if valueLen+valueOffset > len(b) || nextOffset < 0 || nextOffset > len(b) { + err = errInvalidEaBuffer + return + } + + ea.Name = string(b[nameOffset : nameOffset+nameLen]) + ea.Value = b[valueOffset : valueOffset+valueLen] + ea.Flags = info.Flags + if info.NextEntryOffset != 0 { + nb = b[info.NextEntryOffset:] + } + return +} + +// DecodeExtendedAttributes decodes a list of EAs from a FILE_FULL_EA_INFORMATION +// buffer retrieved from BackupRead, ZwQueryEaFile, etc. +func DecodeExtendedAttributes(b []byte) (eas []ExtendedAttribute, err error) { + for len(b) != 0 { + ea, nb, err := parseEa(b) + if err != nil { + return nil, err + } + + eas = append(eas, ea) + b = nb + } + return +} + +func writeEa(buf *bytes.Buffer, ea *ExtendedAttribute, last bool) error { + if int(uint8(len(ea.Name))) != len(ea.Name) { + return errEaNameTooLarge + } + if int(uint16(len(ea.Value))) != len(ea.Value) { + return errEaValueTooLarge + } + entrySize := uint32(fileFullEaInformationSize + len(ea.Name) + 1 + len(ea.Value)) + withPadding := (entrySize + 3) &^ 3 + nextOffset := uint32(0) + if !last { + nextOffset = withPadding + } + info := fileFullEaInformation{ + NextEntryOffset: nextOffset, + Flags: ea.Flags, + NameLength: uint8(len(ea.Name)), + ValueLength: uint16(len(ea.Value)), + } + + err := binary.Write(buf, binary.LittleEndian, &info) + if err != nil { + return err + } + + _, err = buf.Write([]byte(ea.Name)) + if err != nil { + return err + } + + err = buf.WriteByte(0) + if err != nil { + return err + } + + _, err = buf.Write(ea.Value) + if err != nil { + return err + } + + _, err = buf.Write([]byte{0, 0, 0}[0 : withPadding-entrySize]) + if err != nil { + return err + } + + return nil +} + +// EncodeExtendedAttributes encodes a list of EAs into a FILE_FULL_EA_INFORMATION +// buffer for use with BackupWrite, ZwSetEaFile, etc. +func EncodeExtendedAttributes(eas []ExtendedAttribute) ([]byte, error) { + var buf bytes.Buffer + for i := range eas { + last := false + if i == len(eas)-1 { + last = true + } + + err := writeEa(&buf, &eas[i], last) + if err != nil { + return nil, err + } + } + return buf.Bytes(), nil +} |