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Code Issues Releases Wiki Activity

fix hangs due to stale rng status (#195)

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mruddy 2017-07-19 05:54:26 -04:00 committed by Pavol Rusnak
parent 980bae6cb5
commit 1c55ec0fb3
4 changed files with 13 additions and 2 deletions
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6
Makefile.include
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@ -65,6 +65,12 @@ else
CFLAGS += -DMEMORY_PROTECT=1 CFLAGS += -DMEMORY_PROTECT=1
endif endif
ifeq ($(DEBUG_RNG), 1)
CFLAGS += -DDEBUG_RNG=1
else
CFLAGS += -DDEBUG_RNG=0
endif
LDFLAGS += --static \ LDFLAGS += --static \
-Wl,--start-group \ -Wl,--start-group \
-lc \ -lc \

2
firmware/fsm.c
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@ -330,12 +330,14 @@ void fsm_msgWipeDevice(WipeDevice *msg)
void fsm_msgGetEntropy(GetEntropy *msg) void fsm_msgGetEntropy(GetEntropy *msg)
{ {
#if !DEBUG_RNG
layoutDialogSwipe(&bmp_icon_question, _("Cancel"), _("Confirm"), NULL, _("Do you really want to"), _("send entropy?"), NULL, NULL, NULL, NULL); layoutDialogSwipe(&bmp_icon_question, _("Cancel"), _("Confirm"), NULL, _("Do you really want to"), _("send entropy?"), NULL, NULL, NULL, NULL);
if (!protectButton(ButtonRequestType_ButtonRequest_ProtectCall, false)) { if (!protectButton(ButtonRequestType_ButtonRequest_ProtectCall, false)) {
fsm_sendFailure(FailureType_Failure_ActionCancelled, NULL); fsm_sendFailure(FailureType_Failure_ActionCancelled, NULL);
layoutHome(); layoutHome();
return; return;
} }
#endif
RESP_INIT(Entropy); RESP_INIT(Entropy);
uint32_t len = msg->size; uint32_t len = msg->size;
if (len > 1024) { if (len > 1024) {

2
rng.c
View File

@ -27,7 +27,7 @@ uint32_t random32(void)
{ {
static uint32_t last = 0, new = 0; static uint32_t last = 0, new = 0;
while (new == last) { while (new == last) {
if (((RNG_SR & (RNG_SR_SEIS | RNG_SR_CEIS)) == 0) && ((RNG_SR & RNG_SR_DRDY) > 0)) { if ((RNG_SR & (RNG_SR_SECS | RNG_SR_CECS | RNG_SR_DRDY)) == RNG_SR_DRDY) {
new = RNG_DR; new = RNG_DR;
} }
} }

5
setup.c
View File

@ -42,7 +42,7 @@ void setup(void)
// enable RNG // enable RNG
rcc_periph_clock_enable(RCC_RNG); rcc_periph_clock_enable(RCC_RNG);
RNG_CR |= RNG_CR_IE | RNG_CR_RNGEN; RNG_CR |= RNG_CR_RNGEN;
// to be extra careful and heed the STM32F205xx Reference manual, Section 20.3.1 // to be extra careful and heed the STM32F205xx Reference manual, Section 20.3.1
// we don't use the first random number generated after setting the RNGEN bit in setup // we don't use the first random number generated after setting the RNGEN bit in setup
random32(); random32();
@ -73,6 +73,9 @@ void setup(void)
void setupApp(void) void setupApp(void)
{ {
// for completeness, disable RNG peripheral interrupts for old bootloaders that had
// enabled them in RNG control register (the RNG interrupt was never enabled in the NVIC)
RNG_CR &= ~RNG_CR_IE;
// the static variables in random32 are separate between the bootloader and firmware. // the static variables in random32 are separate between the bootloader and firmware.
// therefore, they need to be initialized here so that we can be sure to avoid dupes. // therefore, they need to be initialized here so that we can be sure to avoid dupes.
// this is to try to comply with STM32F205xx Reference manual - Section 20.3.1: // this is to try to comply with STM32F205xx Reference manual - Section 20.3.1: