frostfs-api-go/pkg/checksum.go
Leonard Lyubich 0f04087543 [#230] pkg: Implement string encode/decode methods on Checksum
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
2020-12-25 16:20:26 +03:00

145 lines
3.1 KiB
Go

package pkg
import (
"bytes"
"crypto/sha256"
"encoding/hex"
"github.com/nspcc-dev/neofs-api-go/v2/refs"
"github.com/pkg/errors"
)
// Checksum represents v2-compatible checksum.
type Checksum refs.Checksum
// ChecksumType represents the enumeration
// of checksum types.
type ChecksumType uint8
const (
// ChecksumUnknown is an undefined checksum type.
ChecksumUnknown ChecksumType = iota
// ChecksumSHA256 is a SHA256 checksum type.
ChecksumSHA256
// ChecksumTZ is a Tillich-Zemor checksum type.
ChecksumTZ
)
// NewChecksumFromV2 wraps v2 Checksum message to Checksum.
func NewChecksumFromV2(cV2 *refs.Checksum) *Checksum {
return (*Checksum)(cV2)
}
// NewVersion creates and initializes blank Version.
//
// Works similar as NewVersionFromV2(new(Version)).
func NewChecksum() *Checksum {
return NewChecksumFromV2(new(refs.Checksum))
}
// Type returns checksum type.
func (c *Checksum) Type() ChecksumType {
switch (*refs.Checksum)(c).GetType() {
case refs.SHA256:
return ChecksumSHA256
case refs.TillichZemor:
return ChecksumTZ
default:
return ChecksumUnknown
}
}
// Sum returns checksum bytes.
func (c *Checksum) Sum() []byte {
return (*refs.Checksum)(c).GetSum()
}
// SetSHA256 sets checksum to SHA256 hash.
func (c *Checksum) SetSHA256(v [sha256.Size]byte) {
checksum := (*refs.Checksum)(c)
checksum.SetType(refs.SHA256)
checksum.SetSum(v[:])
}
// SetTillichZemor sets checksum to Tillich-Zemor hash.
func (c *Checksum) SetTillichZemor(v [64]byte) {
checksum := (*refs.Checksum)(c)
checksum.SetType(refs.TillichZemor)
checksum.SetSum(v[:])
}
func (c *Checksum) ToV2() *refs.Checksum {
return (*refs.Checksum)(c)
}
func EqualChecksums(cs1, cs2 *Checksum) bool {
return cs1.Type() == cs2.Type() && bytes.Equal(cs1.Sum(), cs2.Sum())
}
// Marshal marshals Checksum into a protobuf binary form.
//
// Buffer is allocated when the argument is empty.
// Otherwise, the first buffer is used.
func (c *Checksum) Marshal(b ...[]byte) ([]byte, error) {
var buf []byte
if len(b) > 0 {
buf = b[0]
}
return (*refs.Checksum)(c).
StableMarshal(buf)
}
// Unmarshal unmarshals protobuf binary representation of Checksum.
func (c *Checksum) Unmarshal(data []byte) error {
return (*refs.Checksum)(c).
Unmarshal(data)
}
// MarshalJSON encodes Checksum to protobuf JSON format.
func (c *Checksum) MarshalJSON() ([]byte, error) {
return (*refs.Checksum)(c).
MarshalJSON()
}
// UnmarshalJSON decodes Checksum from protobuf JSON format.
func (c *Checksum) UnmarshalJSON(data []byte) error {
return (*refs.Checksum)(c).
UnmarshalJSON(data)
}
func (c *Checksum) String() string {
return hex.EncodeToString(
(*refs.Checksum)(c).
GetSum(),
)
}
// Parse parses Checksum from its string representation.
func (c *Checksum) Parse(s string) error {
data, err := hex.DecodeString(s)
if err != nil {
return err
}
var typ refs.ChecksumType
switch ln := len(data); ln {
default:
return errors.Errorf("unsupported checksum length %d", ln)
case sha256.Size:
typ = refs.SHA256
case 64:
typ = refs.TillichZemor
}
cV2 := (*refs.Checksum)(c)
cV2.SetType(typ)
cV2.SetSum(data)
return nil
}