From ed27e314eb6e6eb79d47c4bcff6fc8600a5bee0a Mon Sep 17 00:00:00 2001
From: Alex Wilson <alex@cooperi.net>
Date: Mon, 1 Mar 2021 10:37:31 +1000
Subject: [PATCH] Only send NIST RID in APT '79' '4F' tag

See discussion on #43
---
 src/net/cooperi/pivapplet/PivApplet.java | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/net/cooperi/pivapplet/PivApplet.java b/src/net/cooperi/pivapplet/PivApplet.java
index e543394..cdc4a09 100644
--- a/src/net/cooperi/pivapplet/PivApplet.java
+++ b/src/net/cooperi/pivapplet/PivApplet.java
@@ -874,9 +874,14 @@ else if (key == (byte)0x81)
 		wtlv.writeTagRealLen((byte)0x4F, (short)PIV_AID.length);
 		wtlv.write(PIV_AID, (short)0, (short)PIV_AID.length);
 
+		/*
+		 * The NIST demo cards only return the first 5 bytes of the AID
+		 * here (the NIST RID). The spec is not especially explicit
+		 * about it, but we'll go with that.
+		 */
 		wtlv.push((byte)0x79);
-		wtlv.writeTagRealLen((byte)0x4F, (short)PIV_AID.length);
-		wtlv.write(PIV_AID, (short)0, (short)PIV_AID.length);
+		wtlv.writeTagRealLen((byte)0x4F, (short)5);
+		wtlv.write(PIV_AID, (short)0, (short)5);
 		wtlv.pop();
 
 		wtlv.writeTagRealLen((byte)0x50, (short)APP_NAME.length);