Change in simtrace2[master]: cardem: choose a more reasonable default ATR

laforge gerrit-no-reply at lists.osmocom.org
Sun Apr 4 15:00:59 UTC 2021


Hello Hoernchen,

I'd like you to do a code review. Please visit

    https://gerrit.osmocom.org/c/simtrace2/+/23611

to review the following change.


Change subject: cardem: choose a more reasonable default ATR
......................................................................

cardem: choose a more reasonable default ATR

PCSCd does not like invalid ATRs

Change-Id: I1eebfdc06be55931c2e80e2b515ac3a559737c38
---
M firmware/libcommon/source/card_emu.c
M host/src/simtrace2-cardem-pcsc.c
2 files changed, 39 insertions(+), 3 deletions(-)



  git pull ssh://gerrit.osmocom.org:29418/simtrace2 refs/changes/11/23611/1

diff --git a/firmware/libcommon/source/card_emu.c b/firmware/libcommon/source/card_emu.c
index cad24b8..099fed1 100644
--- a/firmware/libcommon/source/card_emu.c
+++ b/firmware/libcommon/source/card_emu.c
@@ -1179,8 +1179,24 @@
 	}
 }
 
-/* shortest ATR possible (uses default speed and no options) */
-static const uint8_t default_atr[] = { 0x3B, 0x00 };
+/* reasonable ATR offering all protocols and voltages
+ * smartphones might not care, but other readers do
+
+TS = 0x3B	Direct Convention
+T0 = 0x80	Y(1): b1000, K: 0 (historical bytes)
+TD(1) = 0x80	Y(i+1) = b1000, Protocol T=0
+----
+TD(2) = 0x81	Y(i+1) = b1000, Protocol T=1
+----
+TD(3) = 0x1F	Y(i+1) = b0001, Protocol T=15
+----
+TA(4) = 0xC7	Clock stop: no preference - Class accepted by the card: (3G) A 5V B 3V C 1.8V
+----
+Historical bytes
+TCK = 0x59 	correct checksum
+
+ * */
+static const uint8_t default_atr[] = { 0x3B, 0x80, 0x80, 0x81 , 0x1F, 0xC7, 0x59};
 
 static struct card_handle card_handles[NUM_SLOTS];
 
diff --git a/host/src/simtrace2-cardem-pcsc.c b/host/src/simtrace2-cardem-pcsc.c
index 883bad1..ad3e0f3 100644
--- a/host/src/simtrace2-cardem-pcsc.c
+++ b/host/src/simtrace2-cardem-pcsc.c
@@ -52,6 +52,26 @@
 
 #define ATR_MAX_LEN 33
 
+/*
+reasonable ATR offering all protocols and voltages
+smartphones might not care, but other readers do
+
+TS = 0x3B	Direct Convention
+T0 = 0x80	Y(1): b1000, K: 0 (historical bytes)
+TD(1) = 0x80	Y(i+1) = b1000, Protocol T=0
+----
+TD(2) = 0x81	Y(i+1) = b1000, Protocol T=1
+----
+TD(3) = 0x1F	Y(i+1) = b0001, Protocol T=15
+----
+TA(4) = 0xC7	Clock stop: no preference - Class accepted by the card: (3G) A 5V B 3V C 1.8V
+----
+Historical bytes
+TCK = 0x59 	correct checksum
+*/
+#define DEFAULT_ATR_STR "3B8080811FC759"
+
+
 static void atr_update_csum(uint8_t *atr, unsigned int atr_len)
 {
 	uint8_t csum = 0;
@@ -274,7 +294,7 @@
 	int rc;
 	int c, ret = 1;
 	int skip_atr = 0;
-	char *atr = "3b00";
+	char *atr = DEFAULT_ATR_STR;
 	uint8_t real_atr[ATR_MAX_LEN];
 	int atr_len;
 	int keep_running = 0;

-- 
To view, visit https://gerrit.osmocom.org/c/simtrace2/+/23611
To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings

Gerrit-Project: simtrace2
Gerrit-Branch: master
Gerrit-Change-Id: I1eebfdc06be55931c2e80e2b515ac3a559737c38
Gerrit-Change-Number: 23611
Gerrit-PatchSet: 1
Gerrit-Owner: laforge <laforge at osmocom.org>
Gerrit-Reviewer: Hoernchen <ewild at sysmocom.de>
Gerrit-MessageType: newchange
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osmocom.org/pipermail/gerrit-log/attachments/20210404/b1d7edb6/attachment.htm>


More information about the gerrit-log mailing list