Add replaceraw

pkg/visitors/helpers_test.go

@@ -16,6 +16,7 @@ import (
 // This GUID exists somewhere in the OVMF image.
 var testGUID = guid.MustParse("DF1CCEF6-F301-4A63-9661-FC6030DCC880")
 var dxeCoreGUID = guid.MustParse("D6A2CB7F-6A18-4E2F-B43B-9920A733700A")
+var microcodeRawGUID = guid.MustParse("1B45CC0A-156A-428A-AF62-49864DA0E6E6")
 
 func parseImage(t *testing.T) uefi.Firmware {
 	image, err := os.ReadFile("../../integration/roms/OVMF.rom")

pkg/visitors/replaceraw.go

@@ -0,0 +1,91 @@
+// Copyright 2026 the LinuxBoot Authors. All rights reserved
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package visitors
+
+import (
+	"errors"
+	"os"
+
+	"github.com/linuxboot/fiano/pkg/uefi"
+)
+
+// ReplaceRaw replaces EFI_SECTION_RAW sections with NewRaw for all files matching Predicate.
+type ReplaceRaw struct {
+	// Input
+	Predicate func(f uefi.Firmware) bool
+	NewRaw    []byte
+
+	// Output
+	Matches []uefi.Firmware
+}
+
+// Run wraps Visit and performs some setup and teardown tasks.
+func (v *ReplaceRaw) Run(f uefi.Firmware) error {
+	// Run "find" to generate a list of matches to replace.
+	find := Find{
+		Predicate: v.Predicate,
+	}
+	if err := find.Run(f); err != nil {
+		return err
+	}
+
+	v.Matches = find.Matches
+	if len(find.Matches) == 0 {
+		return errors.New("no matches found for replacement")
+	}
+	if len(find.Matches) > 1 {
+		return errors.New("multiple matches found! There can be only one. Use find to list all matches")
+	}
+
+	for _, m := range v.Matches {
+		if err := m.Apply(v); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// Visit applies the ReplaceRaw visitor to any Firmware type.
+func (v *ReplaceRaw) Visit(f uefi.Firmware) error {
+	switch f := f.(type) {
+
+	case *uefi.File:
+		return f.ApplyChildren(v)
+
+	case *uefi.Section:
+		if f.Header.Type == uefi.SectionTypeRaw {
+			f.SetBuf(v.NewRaw)
+			f.Encapsulated = nil // Raw sections have no encapsulated children
+			if err := f.GenSecHeader(); err != nil {
+				return err
+			}
+		}
+		return f.ApplyChildren(v)
+
+	default:
+		// Must be applied to a File to have any effect.
+		return nil
+	}
+}
+
+func init() {
+	RegisterCLI("replace_raw", "replace a raw section given a GUID or name and new file", 2, func(args []string) (uefi.Visitor, error) {
+		pred, err := FindFilePredicate(args[0])
+		if err != nil {
+			return nil, err
+		}
+
+		filename := args[1]
+		newRaw, err := os.ReadFile(filename)
+		if err != nil {
+			return nil, err
+		}
+
+		return &ReplaceRaw{
+			Predicate: pred,
+			NewRaw:    newRaw,
+		}, nil
+	})
+}

pkg/visitors/replaceraw_test.go

@@ -0,0 +1,76 @@
+// Copyright 2026 the LinuxBoot Authors. All rights reserved
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package visitors
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/linuxboot/fiano/pkg/uefi"
+)
+
+func TestReplaceRaw(t *testing.T) {
+	f := parseImage(t)
+
+	replace := &ReplaceRaw{
+		Predicate: FindFileGUIDPredicate(*microcodeRawGUID),
+		NewRaw:    []byte("banana"),
+	}
+	if err := replace.Run(f); err != nil {
+		t.Fatal(err)
+	}
+
+	if len(replace.Matches) != 1 {
+		t.Fatalf("got %d matches; expected 1", len(replace.Matches))
+	}
+
+	results := find(t, f, microcodeRawGUID)
+	if len(results) != 1 {
+		t.Fatalf("got %d matches; expected 1", len(results))
+	}
+	want := []byte{0x0a, 0x00, 0x00, byte(uefi.SectionTypeRaw), 'b', 'a', 'n', 'a', 'n', 'a'}
+	file, ok := results[0].(*uefi.File)
+	if !ok {
+		t.Fatalf("did not match a file, got type :%T", file)
+	}
+	got := file.Sections[0].Buf()
+	if !reflect.DeepEqual(want, got) {
+		t.Fatalf("want %v; got %v", want, got)
+	}
+}
+
+func TestReplaceRawErrors(t *testing.T) {
+	f := parseImage(t)
+
+	var tests = []struct {
+		name   string
+		newRaw []byte
+		match  string
+		err    string
+	}{
+		{"No Matches", []byte("banana"), "no-match-string",
+			"no matches found for replacement"},
+		{"Multiple Matches", []byte("banana"), ".*",
+			"multiple matches found! There can be only one. Use find to list all matches"},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			pred, err := FindFilePredicate(test.match)
+			if err != nil {
+				t.Fatal(err)
+			}
+			replace := &ReplaceRaw{
+				Predicate: pred,
+				NewRaw:    test.newRaw,
+			}
+			err = replace.Run(f)
+			if err == nil {
+				t.Fatalf("Expected Error (%v), got nil", test.err)
+			} else if err.Error() != test.err {
+				t.Fatalf("Mismatched Error: Expected %v, got %v", test.err, err.Error())
+			}
+		})
+	}
+}