add proof verification to sigsum-debug

1 files changed, 28 insertions, 2 deletions

diff --git a/cmd/sigsum-debug/head/consistency/consistency.go b/cmd/sigsum-debug/head/consistency/consistency.go
index 18fbdd6..c4feb94 100644
--- a/cmd/sigsum-debug/head/consistency/consistency.go
+++ b/cmd/sigsum-debug/head/consistency/consistency.go
@@ -1,9 +1,35 @@
 package consistency
 
 import (
+	"bytes"
 	"fmt"
+
+	"git.sigsum.org/sigsum-go/internal/fmtio"
+	"git.sigsum.org/sigsum-go/pkg/types"
 )
 
-func Main(args []string, oldSize, newSize uint64, oldRoot, newRoot string) error {
-	return fmt.Errorf("TODO")
+func Main(args []string, optOldSize, optNewSize uint64, optOldRoot, optNewRoot string) error {
+	if len(args) != 0 {
+		return fmt.Errorf("trailing arguments: %v", args)
+	}
+	b, err := fmtio.BytesFromStdin()
+	if err != nil {
+		return fmt.Errorf("read: %w", err)
+	}
+	var proof types.ConsistencyProof
+	if err := proof.FromASCII(bytes.NewBuffer(b), optOldSize, optNewSize); err != nil {
+		return fmt.Errorf("parse proof: %w", err)
+	}
+	oldRoot, err := fmtio.HashFromHex(optOldRoot)
+	if err != nil {
+		return fmt.Errorf("parse old root: %w", err)
+	}
+	newRoot, err := fmtio.HashFromHex(optNewRoot)
+	if err != nil {
+		return fmt.Errorf("parse new root: %w", err)
+	}
+	if err := proof.Verify(&oldRoot, &newRoot); err != nil {
+		return fmt.Errorf("verify: %w", err)
+	}
+	return nil
 }