bump buildah to latest

Also includes a small change to make us of
https://github.com/containers/buildah/pull/5039

Signed-off-by: Paul Holzinger <pholzing@redhat.com>

vendor/github.com/containers/luksy/luks.go

@@ -0,0 +1,75 @@
+package luksy
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"os"
+)
+
+// ReadHeaderOptions can control some of what ReadHeaders() does.
+type ReadHeaderOptions struct{}
+
+// ReadHeaders reads LUKS headers from the specified file, returning either a
+// LUKSv1 header, or two LUKSv2 headers and a LUKSv2 JSON block, depending on
+// which format is detected.
+func ReadHeaders(f *os.File, options ReadHeaderOptions) (*V1Header, *V2Header, *V2Header, *V2JSON, error) {
+	var v1 V1Header
+	var v2a, v2b V2Header
+	n, err := f.ReadAt(v2a[:], 0)
+	if err != nil {
+		return nil, nil, nil, nil, err
+	}
+	if n != len(v2a) {
+		return nil, nil, nil, nil, fmt.Errorf("only able to read %d bytes - file truncated?", n)
+	}
+	if n, err = f.ReadAt(v1[:], 0); err != nil {
+		return nil, nil, nil, nil, err
+	}
+	if n != len(v1) {
+		return nil, nil, nil, nil, fmt.Errorf("only able to read %d bytes - file truncated?", n)
+	}
+	if v2a.Magic() != V2Magic1 {
+		return nil, nil, nil, nil, fmt.Errorf("internal error: magic mismatch in LUKS header (%q)", v2a.Magic())
+	}
+	switch v2a.Version() { // is it a v1 header, or the first v2 header?
+	case 1:
+		return &v1, nil, nil, nil, nil
+	case 2:
+		size := v2a.HeaderSize()
+		if size > 0x7fffffffffffffff {
+			return nil, nil, nil, nil, fmt.Errorf("unsupported header size while looking for second header")
+		}
+		if size < 4096 {
+			return nil, nil, nil, nil, fmt.Errorf("unsupported header size while looking for JSON data")
+		}
+		if n, err = f.ReadAt(v2b[:], int64(size)); err != nil || n != len(v2b) {
+			if err == nil && n != len(v2b) {
+				err = fmt.Errorf("short read: read only %d bytes, should have read %d", n, len(v2b))
+			}
+			return nil, nil, nil, nil, err
+		}
+		if v2b.Magic() != V2Magic2 {
+			return nil, nil, nil, nil, fmt.Errorf("internal error: magic mismatch in second LUKS header (%q)", v2b.Magic())
+		}
+		jsonSize := size - 4096
+		buf := make([]byte, jsonSize)
+		n, err = f.ReadAt(buf[:], 4096)
+		if err != nil {
+			return nil, nil, nil, nil, fmt.Errorf("internal error: while reading JSON data: %w", err)
+		}
+		if n < 0 || uint64(n) != jsonSize {
+			return nil, nil, nil, nil, fmt.Errorf("internal error: short read while reading JSON data (wanted %d, got %d)", jsonSize, n)
+		}
+		var jsonData V2JSON
+		buf = bytes.TrimRightFunc(buf, func(r rune) bool { return r == 0 })
+		if err = json.Unmarshal(buf, &jsonData); err != nil {
+			return nil, nil, nil, nil, fmt.Errorf("internal error: decoding JSON data: %w", err)
+		}
+		if uint64(jsonData.Config.JsonSize) != jsonSize {
+			return nil, nil, nil, nil, fmt.Errorf("internal error: JSON data size mismatch: (expected %d, used %d)", jsonData.Config.JsonSize, jsonSize)
+		}
+		return nil, &v2a, &v2b, &jsonData, nil
+	}
+	return nil, nil, nil, nil, fmt.Errorf("error reading LUKS header - magic identifier not found")
+}