97 lines
2.6 KiB
Go
97 lines
2.6 KiB
Go
|
package refs
|
||
|
|
||
|
import (
|
||
|
"bytes"
|
||
|
"crypto/sha256"
|
||
|
|
||
|
"github.com/mr-tron/base58"
|
||
|
"github.com/pkg/errors"
|
||
|
)
|
||
|
|
||
|
// CIDForBytes creates CID for passed bytes.
|
||
|
func CIDForBytes(data []byte) CID { return sha256.Sum256(data) }
|
||
|
|
||
|
// CIDFromBytes parses CID from passed bytes.
|
||
|
func CIDFromBytes(data []byte) (cid CID, err error) {
|
||
|
if ln := len(data); ln != CIDSize {
|
||
|
return CID{}, errors.Wrapf(ErrWrongDataSize, "expect=%d, actual=%d", CIDSize, ln)
|
||
|
}
|
||
|
|
||
|
copy(cid[:], data)
|
||
|
return
|
||
|
}
|
||
|
|
||
|
// CIDFromString parses CID from string representation of CID.
|
||
|
func CIDFromString(c string) (CID, error) {
|
||
|
var cid CID
|
||
|
decoded, err := base58.Decode(c)
|
||
|
if err != nil {
|
||
|
return cid, err
|
||
|
}
|
||
|
return CIDFromBytes(decoded)
|
||
|
}
|
||
|
|
||
|
// Size returns size of CID (CIDSize).
|
||
|
func (c CID) Size() int { return CIDSize }
|
||
|
|
||
|
// Parse tries to parse CID from string representation.
|
||
|
func (c *CID) Parse(cid string) error {
|
||
|
var err error
|
||
|
if *c, err = CIDFromString(cid); err != nil {
|
||
|
return err
|
||
|
}
|
||
|
return nil
|
||
|
}
|
||
|
|
||
|
// Empty checks that current CID is empty.
|
||
|
func (c CID) Empty() bool { return bytes.Equal(c.Bytes(), emptyCID) }
|
||
|
|
||
|
// Equal checks that current CID is equal to passed CID.
|
||
|
func (c CID) Equal(cid CID) bool { return bytes.Equal(c.Bytes(), cid.Bytes()) }
|
||
|
|
||
|
// Marshal returns CID bytes representation.
|
||
|
func (c CID) Marshal() ([]byte, error) { return c.Bytes(), nil }
|
||
|
|
||
|
// MarshalBinary returns CID bytes representation.
|
||
|
func (c CID) MarshalBinary() ([]byte, error) { return c.Bytes(), nil }
|
||
|
|
||
|
// MarshalTo marshal CID to bytes representation into passed bytes.
|
||
|
func (c *CID) MarshalTo(data []byte) (int, error) { return copy(data, c.Bytes()), nil }
|
||
|
|
||
|
// ProtoMessage method to satisfy proto.Message interface.
|
||
|
func (c CID) ProtoMessage() {}
|
||
|
|
||
|
// String returns string representation of CID.
|
||
|
func (c CID) String() string { return base58.Encode(c[:]) }
|
||
|
|
||
|
// Reset resets current CID to zero value.
|
||
|
func (c *CID) Reset() { *c = CID{} }
|
||
|
|
||
|
// Bytes returns CID bytes representation.
|
||
|
func (c CID) Bytes() []byte {
|
||
|
buf := make([]byte, CIDSize)
|
||
|
copy(buf, c[:])
|
||
|
return buf
|
||
|
}
|
||
|
|
||
|
// UnmarshalBinary tries to parse bytes representation of CID.
|
||
|
func (c *CID) UnmarshalBinary(data []byte) error { return c.Unmarshal(data) }
|
||
|
|
||
|
// Unmarshal tries to parse bytes representation of CID.
|
||
|
func (c *CID) Unmarshal(data []byte) error {
|
||
|
if ln := len(data); ln != CIDSize {
|
||
|
return errors.Wrapf(ErrWrongDataSize, "expect=%d, actual=%d", CIDSize, ln)
|
||
|
}
|
||
|
|
||
|
copy((*c)[:], data)
|
||
|
return nil
|
||
|
}
|
||
|
|
||
|
// Verify validates that current CID is generated for passed bytes data.
|
||
|
func (c CID) Verify(data []byte) error {
|
||
|
if id := CIDForBytes(data); !bytes.Equal(c[:], id[:]) {
|
||
|
return errors.New("wrong hash for data")
|
||
|
}
|
||
|
return nil
|
||
|
}
|