From cf81a82645de336464bfad944945d7c98cf072f1 Mon Sep 17 00:00:00 2001
From: Pol Henarejos <pol.henarejos@cttc.es>
Date: Mon, 4 Apr 2022 15:48:04 +0200
Subject: [PATCH] Added a new custom APDU (88h) for setting and retrieving
 datetime.

Signed-off-by: Pol Henarejos <pol.henarejos@cttc.es>
---
 src/hsm/hsm2040.c | 17 ++++++++++++++++-
 src/hsm/sc_hsm.c  | 39 +++++++++++++++++++++++++++------------
 2 files changed, 43 insertions(+), 13 deletions(-)

diff --git a/src/hsm/hsm2040.c b/src/hsm/hsm2040.c
index 228b1d5..93d2cd6 100644
--- a/src/hsm/hsm2040.c
+++ b/src/hsm/hsm2040.c
@@ -1605,6 +1605,21 @@ void led_off_all()
 #endif
 }
 
+void init_rtc() {
+    
+    rtc_init();
+    datetime_t dt = {
+            .year  = 2020,
+            .month = 1,
+            .day   = 1,
+            .dotw  = 3, // 0 is Sunday, so 5 is Friday
+            .hour  = 00,
+            .min   = 00,
+            .sec   = 00
+    };
+    rtc_set_datetime(&dt);
+}
+
 extern void neug_task();
 
 pico_unique_board_id_t unique_id;
@@ -1641,7 +1656,7 @@ int main(void)
     
     low_flash_init();
     
-    rtc_init();
+    init_rtc();
       
     while (1)
     {
diff --git a/src/hsm/sc_hsm.c b/src/hsm/sc_hsm.c
index 21c6ee6..24a0c3c 100644
--- a/src/hsm/sc_hsm.c
+++ b/src/hsm/sc_hsm.c
@@ -1717,18 +1717,33 @@ static int cmd_derive_asym() {
 static int cmd_datetime() {
     if (P1(apdu) != 0x0 || P2(apdu) != 0x0)
         return SW_INCORRECT_P1P2();
-    if (apdu.cmd_apdu_data_len != 8)
-        return SW_WRONG_LENGTH();
-    datetime_t dt;
-    dt.year = (apdu.cmd_apdu_data[0] << 8) | (apdu.cmd_apdu_data[1]);
-    dt.month = apdu.cmd_apdu_data[2];
-    dt.day = apdu.cmd_apdu_data[3];
-    dt.dotw = apdu.cmd_apdu_data[4];
-    dt.hour = apdu.cmd_apdu_data[5];
-    dt.min = apdu.cmd_apdu_data[6];
-    dt.sec = apdu.cmd_apdu_data[7];
-    if (!rtc_set_datetime(&dt))
-        return SW_WRONG_DATA();
+    if (apdu.cmd_apdu_data_len == 0) {
+        datetime_t dt;
+        if (!rtc_get_datetime(&dt))
+            return SW_EXEC_ERROR();
+        res_APDU[res_APDU_size++] = dt.year >> 8;
+        res_APDU[res_APDU_size++] = dt.year & 0xff;
+        res_APDU[res_APDU_size++] = dt.month;
+        res_APDU[res_APDU_size++] = dt.day;
+        res_APDU[res_APDU_size++] = dt.dotw;
+        res_APDU[res_APDU_size++] = dt.hour;
+        res_APDU[res_APDU_size++] = dt.min;
+        res_APDU[res_APDU_size++] = dt.sec;
+    }
+    else {
+        if (apdu.cmd_apdu_data_len != 8)
+            return SW_WRONG_LENGTH();
+        datetime_t dt;
+        dt.year = (apdu.cmd_apdu_data[0] << 8) | (apdu.cmd_apdu_data[1]);
+        dt.month = apdu.cmd_apdu_data[2];
+        dt.day = apdu.cmd_apdu_data[3];
+        dt.dotw = apdu.cmd_apdu_data[4];
+        dt.hour = apdu.cmd_apdu_data[5];
+        dt.min = apdu.cmd_apdu_data[6];
+        dt.sec = apdu.cmd_apdu_data[7];
+        if (!rtc_set_datetime(&dt))
+            return SW_WRONG_DATA();
+    }
     return SW_OK();
 }