laforge has submitted this change. (
https://gerrit.osmocom.org/c/simtrace2/+/26865 )
Change subject: firmware: bugfix: disable cardemu comms in local SIM mode
......................................................................
firmware: bugfix: disable cardemu comms in local SIM mode
This change prevents contention on the ISO7816 bus by disabling the card
emulation state machine when the SIM switch is in the local mode. Without this
change, the card emulation firmware can clobber ISO7816 communications and
cause contention with certain (but not all) SIM cards.
Changes:
- Add 'enabled' flag to cardemu instance that is set/cleared by
usb_command_sim_select() (the only place where sim switch occurs).
- Flag is initialized as false (disabled) by default, to match local SIM mode
default.
- When card emulation is disabled, force SIM VCC to be "OFF", SIM RESET as
"not in RESET", and drop bytes bytes received on the ISO7816 interface (but do
service buffers).
Change-Id: I4010f988712eac4a6af8568ccd60062f9de62449
---
M firmware/libcommon/source/mode_cardemu.c
1 file changed, 31 insertions(+), 13 deletions(-)
Approvals:
Jenkins Builder: Verified
laforge: Looks good to me, approved
diff --git a/firmware/libcommon/source/mode_cardemu.c
b/firmware/libcommon/source/mode_cardemu.c
index 7fd069a..7f52647 100644
--- a/firmware/libcommon/source/mode_cardemu.c
+++ b/firmware/libcommon/source/mode_cardemu.c
@@ -83,10 +83,21 @@
#ifdef DETECT_VCC_BY_ADC
uint32_t vcc_uv;
#endif
+
+ /*! real-time state of VCC I/O line, irrespective of enabled flag */
bool vcc_active;
+
+ /*! last VCC state we reported to the card emu state machine
(conditioned by enabled flag) */
bool vcc_active_last;
+
+ /*! real-time state of RST I/O line, irrespective of enabled flag */
bool rst_active;
+
+ /*! last RST state we reported to the card emu state machine
(conditioned by enabled flag) */
bool rst_active_last;
+
+ /*! flag indicating whether this instance should perform card
emulation, or not */
+ bool enabled;
};
struct cardem_inst cardem_inst[] = {
@@ -515,19 +526,25 @@
#endif /* DETECT_VCC_BY_ADC */
-/* called from main loop; dispatches card I/O state changes to card_emu from
main loop */
+/**
+ * called from main loop; dispatches card I/O state changes to card_emu from
main loop.
+ * NOTE: conditions I/O state on the ci->enabled flag; if the instance is
disabled, we assume VCC is
+ * disabled and the device is not in reset
+ */
static void process_io_statechg(struct cardem_inst *ci)
{
- if (ci->vcc_active != ci->vcc_active_last) {
- card_emu_io_statechg(ci->ch, CARD_IO_VCC, ci->vcc_active);
+ const bool vcc_active = ci->vcc_active && ci->enabled;
+ if (vcc_active != ci->vcc_active_last) {
+ card_emu_io_statechg(ci->ch, CARD_IO_VCC, vcc_active);
/* FIXME do this for real */
- card_emu_io_statechg(ci->ch, CARD_IO_CLK, ci->vcc_active);
- ci->vcc_active_last = ci->vcc_active;
+ card_emu_io_statechg(ci->ch, CARD_IO_CLK, vcc_active);
+ ci->vcc_active_last = vcc_active;
}
- if (ci->rst_active != ci->rst_active_last) {
- card_emu_io_statechg(ci->ch, CARD_IO_RST, ci->rst_active);
- ci->rst_active_last = ci->rst_active;
+ const bool rst_active = ci->rst_active && ci->enabled;
+ if (rst_active != ci->rst_active_last) {
+ card_emu_io_statechg(ci->ch, CARD_IO_RST, rst_active);
+ ci->rst_active_last = rst_active;
}
}
@@ -778,10 +795,8 @@
if (msgb_l2len(msg) < sizeof(*mss))
return -1;
- if (mss->remote_sim)
- sim_switch_use_physical(ci->num, 0);
- else
- sim_switch_use_physical(ci->num, 1);
+ ci->enabled = mss->remote_sim ? true : false;
+ sim_switch_use_physical(ci->num, !ci->enabled);
return 0;
}
@@ -925,7 +940,10 @@
}
uint8_t byte = rbuf_read(&ci->rb);
__enable_irq();
- card_emu_process_rx_byte(ci->ch, byte);
+
+ if (ci->enabled) {
+ card_emu_process_rx_byte(ci->ch, byte);
+ }
//TRACE_ERROR("%uRx%02x\r\n", i, byte);
}
--
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Gerrit-Project: simtrace2
Gerrit-Branch: master
Gerrit-Change-Id: I4010f988712eac4a6af8568ccd60062f9de62449
Gerrit-Change-Number: 26865
Gerrit-PatchSet: 2
Gerrit-Owner: jtavares <[email protected]>
Gerrit-Reviewer: Hoernchen <[email protected]>
Gerrit-Reviewer: Jenkins Builder
Gerrit-Reviewer: laforge <[email protected]>
Gerrit-MessageType: merged
