From 1d18c143f496be6af20cdf415b88ba85bef1f5e7 Mon Sep 17 00:00:00 2001
From: Werner Koch <wk@gnupg.org>
Date: Fri, 9 Aug 2024 10:08:50 +0200
Subject: [PATCH] agent: When diverting to a card show the name of unsupported
 algos.

* agent/divert-scd.c (divert_pkdecrypt): Improve error message.
---
 agent/divert-scd.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/agent/divert-scd.c b/agent/divert-scd.c
index d390ebb06..74b2c652b 100644
--- a/agent/divert-scd.c
+++ b/agent/divert-scd.c
@@ -468,7 +468,20 @@ divert_pkdecrypt (ctrl_t ctrl,
       n = snext (&s);
     }
   else
-    return gpg_error (GPG_ERR_UNSUPPORTED_ALGORITHM);
+    {
+      if (opt.verbose)
+        {
+          if (smatch (&s, n, "elg"))
+            log_info ("unknown algorithm is \"elg\"\n");
+          else if (smatch (&s, n, "dsa"))
+            log_info ("unknown algorithm is \"dsa\"\n");
+          else if (smatch (&s, n, "kyber"))
+            log_info ("unknown algorithm is \"kyber\"\n");
+          else
+            log_printhex (s, n, "unknown algorithm is");
+        }
+      return gpg_error (GPG_ERR_UNSUPPORTED_ALGORITHM);
+    }
 
   if (!n)
     return gpg_error (GPG_ERR_UNKNOWN_SEXP);