1 files changed, 28 insertions, 0 deletions
diff --git a/cmd/sigsum-debug/pubkey/pubkey.go b/cmd/sigsum-debug/pubkey/pubkey.go
new file mode 100644
index 0000000..8f3b467
--- /dev/null
+++ b/cmd/sigsum-debug/pubkey/pubkey.go
@@ -0,0 +1,28 @@
+package pubkey
+
+import (
+	"crypto/ed25519"
+	"fmt"
+
+	"git.sigsum.org/sigsum-go/pkg/hex"
+	"git.sigsum.org/sigsum-tools-go/internal/util"
+)
+
+func Main(_ []string) error {
+	b, err := util.HexFromStdin()
+	if err != nil {
+		return err
+	}
+	if len(b) != ed25519.PrivateKeySize {
+		return fmt.Errorf("pubkey: invalid key size %d", len(b))
+	}
+
+	priv := ed25519.PrivateKey(b)
+	pub, ok := priv.Public().(ed25519.PublicKey)
+	if !ok {
+		return fmt.Errorf("pubkey: must parse as ed25519")
+	}
+
+	fmt.Printf("%s\n", hex.Serialize(pub[:]))
+	return nil
+}