Use central variable to define system PKCS library location

Signed-off-by: Timothy Pearson <kb9vqf@pearsoncomputing.net>

usr/bin/cryptosmartcard.sh

@@ -21,6 +21,9 @@
 #
 # Updated by Timothy Pearson <kb9vqf@pearsoncomputing.net> 9/15/2015
 # Rewrite to use on-card RSA encryption
+#
+# Updated by Timothy Pearson <kb9vqf@pearsoncomputing.net> 6/02/2020
+# Use central variable for PKCS library location
 
 # define counter-intuitive shell logic values (based on /bin/true & /bin/false)
 TRUE=0
@@ -37,6 +40,9 @@ fi
 # Find plymouth
 PLYDIR=/bin/plymouth
 
+# Set system PKCS library path
+SYSTEM_PKCS_LIBRARY=/usr/lib/opensc-pkcs11.so
+
 # print message to usplash or stderr
 # usage: msg <command> "message" [switch]
 # command: TEXT | STATUS | SUCCESS | FAILURE | CLEAR (see 'man usplash_write' for all commands)
@@ -143,14 +149,14 @@ if [ $LUKS_KEY_COUNT -gt 0 ]; then
 				rm -f /tmp/kmsg
 			fi
 
-			PIN=$(cardpincheck /usr/lib/opensc-pkcs11.so)
+			PIN=$(cardpincheck $SYSTEM_PKCS_LIBRARY)
 			RET=$?
 			if [ $RET -eq 0 ]; then
 				# PIN valid
 				msg "SmartCard unlocked"
 				for KEYFILE in ${LUKS_KEY_DIR}/${DISK_UUID}_slot*; do
 					# Try decrypting
-					echo "$PIN" | cardpincheck /usr/lib/opensc-pkcs11.so $KEYFILE 2> /dev/null
+					echo "$PIN" | cardpincheck $SYSTEM_PKCS_LIBRARY $KEYFILE 2> /dev/null
 					RET=$?
 					if [ $RET -eq 0 ]; then
 						OPENED=$TRUE