From f964df4eb51465d7b00ac3fcb25661e45a3e5be7 Mon Sep 17 00:00:00 2001
From: Supreeth Herle <herlesupreeth@gmail.com>
Date: Tue, 24 Mar 2020 13:15:37 +0100
Subject: [PATCH] sysmoISIM-SJA2: Add support for programming EF.ePDGSelection
 (ePDG Selection Information)

If the EF.ePDGSelection is present, it is populated with a single entry with PLMN 1 set
to Home PLMN of USIM, ePDG FQDN format set to Operator Identifier FQDN and ePDG Priority value
set to 1.

Change-Id: I92f3f813afa41ae497ebc0dc2ca73da810f82364
---
 pySim-prog.py  | 13 +++++++++++++
 pySim/cards.py | 21 +++++++++++++++++++++
 2 files changed, 34 insertions(+)

diff --git a/pySim-prog.py b/pySim-prog.py
index e172d80c..93ae924a 100755
--- a/pySim-prog.py
+++ b/pySim-prog.py
@@ -150,6 +150,9 @@ def parse_options():
 	parser.add_option("--epdgid", dest="epdgid",
 			help="Set Home Evolved Packet Data Gateway (ePDG) Identifier. (Only FQDN format supported)",
 		)
+	parser.add_option("--epdgSelection", dest="epdgSelection",
+			help="Set PLMN for ePDG Selection Information. (Only Operator Identifier FQDN format supported)",
+		)
 	parser.add_option("--read-imsi", dest="read_imsi", action="store_true",
 			help="Read the IMSI from the CARD", default=False
 		)
@@ -433,6 +436,15 @@ def gen_parameters(opts):
 
 	pin_adm = sanitize_pin_adm(opts)
 
+	# ePDG Selection Information
+	if opts.epdgSelection:
+		if len(opts.epdgSelection) < 5 or len(opts.epdgSelection) > 6:
+			raise ValueError('ePDG Selection Information is not valid')
+		epdg_mcc = opts.epdgSelection[:3]
+		epdg_mnc = opts.epdgSelection[3:]
+		if not epdg_mcc.isdigit() or not epdg_mnc.isdigit():
+			raise ValueError('PLMN for ePDG Selection must only contain decimal digits')
+
 	# Return that
 	return {
 		'name'	: opts.name,
@@ -447,6 +459,7 @@ def gen_parameters(opts):
 		'pin_adm' : pin_adm,
 		'msisdn' : opts.msisdn,
 		'epdgid' : opts.epdgid,
+		'epdgSelection' : opts.epdgSelection,
 	}
 
 
diff --git a/pySim/cards.py b/pySim/cards.py
index 6243d4a6..dc612dfe 100644
--- a/pySim/cards.py
+++ b/pySim/cards.py
@@ -284,6 +284,16 @@ class UsimCard(Card):
 		else:
 			return (None, sw)
 
+	def update_ePDGSelection(self, mcc, mnc):
+		(res, sw) = self._scc.read_binary(EF_USIM_ADF_map['ePDGSelection'], length=None, offset=0)
+		if sw == '9000' and (len(mcc) == 0 or len(mnc) == 0):
+			# Reset contents
+			# 80 - Tag value
+			(res, sw) = self._scc.update_binary(EF_USIM_ADF_map['ePDGSelection'], rpad('', len(res)))
+		elif sw == '9000':
+			(res, sw) = self._scc.update_binary(EF_USIM_ADF_map['ePDGSelection'], enc_ePDGSelection(res, mcc, mnc))
+		return sw
+
 	def read_ust(self):
 		(res, sw) = self._scc.read_binary(EF_USIM_ADF_map['UST'])
 		if sw == '9000':
@@ -1195,6 +1205,17 @@ class SysmoISIMSJA2(UsimCard):
 					if sw != '9000':
 						print("Programming ePDGId failed with code %s"%sw)
 
+			# update EF.ePDGSelection in ADF.USIM
+			if self.file_exists(EF_USIM_ADF_map['ePDGSelection']):
+				if p.get('epdgSelection'):
+					epdg_plmn = p['epdgSelection']
+					sw = self.update_ePDGSelection(epdg_plmn[:3], epdg_plmn[3:])
+				else:
+					sw = self.update_ePDGSelection("", "")
+				if sw != '9000':
+					print("Programming ePDGSelection failed with code %s"%sw)
+
+
 		return