mirror of
https://github.com/octoleo/restic.git
synced 2024-11-16 10:05:25 +00:00
c7b770eb1f
Ideally, code that uses a repository shouldn't directly interact with the underlying backend. Thus, move MemorizeList one layer up.
77 lines
2.1 KiB
Go
77 lines
2.1 KiB
Go
package backend
|
|
|
|
import (
|
|
"bytes"
|
|
"context"
|
|
"encoding/hex"
|
|
"fmt"
|
|
"io"
|
|
|
|
"github.com/minio/sha256-simd"
|
|
|
|
"github.com/restic/restic/internal/debug"
|
|
"github.com/restic/restic/internal/errors"
|
|
)
|
|
|
|
func verifyContentMatchesName(s string, data []byte) (bool, error) {
|
|
if len(s) != hex.EncodedLen(sha256.Size) {
|
|
return false, fmt.Errorf("invalid length for ID: %q", s)
|
|
}
|
|
|
|
b, err := hex.DecodeString(s)
|
|
if err != nil {
|
|
return false, fmt.Errorf("invalid ID: %s", err)
|
|
}
|
|
var id [sha256.Size]byte
|
|
copy(id[:], b)
|
|
|
|
hashed := sha256.Sum256(data)
|
|
return id == hashed, nil
|
|
}
|
|
|
|
// LoadAll reads all data stored in the backend for the handle into the given
|
|
// buffer, which is truncated. If the buffer is not large enough or nil, a new
|
|
// one is allocated.
|
|
func LoadAll(ctx context.Context, buf []byte, be Backend, h Handle) ([]byte, error) {
|
|
retriedInvalidData := false
|
|
err := be.Load(ctx, h, 0, 0, func(rd io.Reader) error {
|
|
// make sure this is idempotent, in case an error occurs this function may be called multiple times!
|
|
wr := bytes.NewBuffer(buf[:0])
|
|
_, cerr := io.Copy(wr, rd)
|
|
if cerr != nil {
|
|
return cerr
|
|
}
|
|
buf = wr.Bytes()
|
|
|
|
// retry loading damaged data only once. If a file fails to download correctly
|
|
// the second time, then it is likely corrupted at the backend. Return the data
|
|
// to the caller in that case to let it decide what to do with the data.
|
|
if !retriedInvalidData && h.Type != ConfigFile {
|
|
if matches, err := verifyContentMatchesName(h.Name, buf); err == nil && !matches {
|
|
debug.Log("retry loading broken blob %v", h)
|
|
retriedInvalidData = true
|
|
return errors.Errorf("loadAll(%v): invalid data returned", h)
|
|
}
|
|
}
|
|
return nil
|
|
})
|
|
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
return buf, nil
|
|
}
|
|
|
|
// LimitedReadCloser wraps io.LimitedReader and exposes the Close() method.
|
|
type LimitedReadCloser struct {
|
|
io.Closer
|
|
io.LimitedReader
|
|
}
|
|
|
|
// LimitReadCloser returns a new reader wraps r in an io.LimitedReader, but also
|
|
// exposes the Close() method.
|
|
func LimitReadCloser(r io.ReadCloser, n int64) *LimitedReadCloser {
|
|
return &LimitedReadCloser{Closer: r, LimitedReader: io.LimitedReader{R: r, N: n}}
|
|
}
|