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sh sniff skip some bytes from data - arm side

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This commit is contained in:
merlokk 2022-07-09 16:45:08 +03:00
parent dcea185ca2
commit 0b95c519ff
3 changed files with 55 additions and 4 deletions
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4
armsrc/appmain.c
View file

@ -1784,11 +1784,13 @@ static void PacketReceived(PacketCommandNG *packet) {
struct p {
uint32_t samplesToSkip;
uint32_t triggersToSkip;
uint8_t skipMode;
uint8_t skipRatio;
} PACKED;
struct p *payload = (struct p *)packet->data.asBytes;
uint16_t len = 0;
int res = HfSniff(payload->samplesToSkip, payload->triggersToSkip, &len);
int res = HfSniff(payload->samplesToSkip, payload->triggersToSkip, &len, payload->skipMode, payload->skipRatio);
struct {
uint16_t len;

46
armsrc/hfsnoop.c
View file

@ -36,7 +36,46 @@ static void RAMFUNC optimizedSniff(uint16_t *dest, uint16_t dsize) {
}
}
int HfSniff(uint32_t samplesToSkip, uint32_t triggersToSkip, uint16_t *len) {
static void RAMFUNC skipSniff(uint8_t *dest, uint16_t dsize, uint8_t skipMode, uint8_t skipRatio) {
uint32_t accum = (skipMode == HF_SNOOP_SKIP_MIN) ? 0xffffffff : 0;
uint8_t ratioindx = 0;
while (dsize > 0) {
if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
volatile uint16_t val = (uint16_t)(AT91C_BASE_SSC->SSC_RHR);
switch (skipMode) {
case HF_SNOOP_SKIP_MAX:
if (accum < (val & 0xff))
accum = val & 0xff;
if (accum < (val << 8))
accum = val << 8;
case HF_SNOOP_SKIP_MIN:
if (accum > (val & 0xff))
accum = val & 0xff;
if (accum > (val << 8))
accum = val << 8;
case HF_SNOOP_SKIP_AVG:
accum += (val & 0xff) + (val << 8);
default: { // HF_SNOOP_SKIP_DROP and the rest
if (ratioindx == 0)
accum = val & 0xff;
}
}
ratioindx++;
if (ratioindx >= skipRatio) {
ratioindx = 0;
if (skipMode == HF_SNOOP_SKIP_AVG)
*dest = accum / (skipRatio * 2);
else
*dest = accum;
dest++;
dsize --;
}
}
}
}
int HfSniff(uint32_t samplesToSkip, uint32_t triggersToSkip, uint16_t *len, uint8_t skipMode, uint8_t skipRatio) {
BigBuf_free();
BigBuf_Clear_ext(false);
@ -105,7 +144,10 @@ int HfSniff(uint32_t samplesToSkip, uint32_t triggersToSkip, uint16_t *len) {
}
}
optimizedSniff((uint16_t *)mem, *len);
if (skipMode == 0)
optimizedSniff((uint16_t *)mem, *len);
else
skipSniff(mem, *len, skipMode, skipRatio);
if (g_dbglevel >= DBG_INFO) {
Dbprintf("Trigger kicked in (%d >= 180)", r);

9
armsrc/hfsnoop.h
View file

@ -18,6 +18,13 @@
#include "proxmark3_arm.h"
int HfSniff(uint32_t samplesToSkip, uint32_t triggersToSkip, uint16_t *len);
// what to do with skipped data
#define HF_SNOOP_SKIP_NONE (0)
#define HF_SNOOP_SKIP_DROP (1)
#define HF_SNOOP_SKIP_MAX (2)
#define HF_SNOOP_SKIP_MIN (3)
#define HF_SNOOP_SKIP_AVG (4)
int HfSniff(uint32_t samplesToSkip, uint32_t triggersToSkip, uint16_t *len, uint8_t skipMode, uint8_t skipRatio);
void HfPlotDownload(void);
#endif