From 57318eaf5b0e9c17f5e86ecb6aa96cbbb2e9384d Mon Sep 17 00:00:00 2001
From: Sun Yimin <emmansun@users.noreply.github.com>
Date: Wed, 8 May 2024 14:35:20 +0800
Subject: [PATCH] x509: include OID in duplicate extension error message

---
 smx509/parser.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/smx509/parser.go b/smx509/parser.go
index 1cb25a4..962df55 100644
--- a/smx509/parser.go
+++ b/smx509/parser.go
@@ -1000,7 +1000,7 @@ func parseCertificate(der []byte) (*Certificate, error) {
 					}
 					oidStr := ext.Id.String()
 					if seenExts[oidStr] {
-						return nil, errors.New("x509: certificate contains duplicate extensions")
+						return nil, fmt.Errorf("x509: certificate contains duplicate extension with OID %q", oidStr)
 					}
 					seenExts[oidStr] = true
 					cert.Extensions = append(cert.Extensions, ext)