Add options to 'lf sniff' for repeated acquisitions

CHANGELOG.md

@@ -4,7 +4,7 @@ This project uses the changelog in accordance with [keepchangelog](http://keepac
 
 ## [unreleased][unreleased]
  - Add lf t55xx sniff to allow extracting commands and passwords used be cloners. (@mwalker33)
- - Add options to `lf read` and `lf cmdread` (@doegox)
+ - Add options to `lf read`, `lf cmdread`, `lf sniff` for repeated acquisitions (@doegox)
  - Change options of `lf read` to match `lf cmdread`, this affects historical `d` and `s` options (@doegox)
  - Add `hf waveshare` to upload picture to Waveshare NFC-Powered e-Paper (@doegox)
  - Add `hf 14a config` to deal with badly configured cards: invalid ATQA/BCC/SAK (@doegox)

armsrc/appmain.c

@@ -786,8 +786,13 @@ static void PacketReceived(PacketCommandNG *packet) {
             break;
         }
         case CMD_LF_SNIFF_RAW_ADC: {
-            uint32_t bits = SniffLF();
+            struct p {
-            reply_mix(CMD_ACK, bits, 0, 0, 0, 0);
+                uint32_t samples : 31;
+                bool     verbose : 1;
+            } PACKED;
+            struct p *payload = (struct p *)packet->data.asBytes;
+            uint32_t bits = SniffLF(payload->verbose, payload->samples);
+            reply_ng(CMD_LF_SNIFF_RAW_ADC, PM3_SUCCESS, (uint8_t *)&bits, sizeof(bits));
             break;
         }
         case CMD_LF_HID_WATCH: {

armsrc/lfsampling.c

@@ -397,9 +397,9 @@ uint32_t SampleLF(bool verbose, uint32_t sample_size) {
 * Initializes the FPGA for sniffer-mode (field off), and acquires the samples.
 * @return number of bits sampled
 **/
-uint32_t SniffLF(void) {
+uint32_t SniffLF(bool verbose, uint32_t sample_size) {
     BigBuf_Clear_ext(false);
-    return ReadLF(false, true, 0);
+    return ReadLF(false, verbose, sample_size);
 }
 
 /**

armsrc/lfsampling.h

@@ -40,7 +40,7 @@ uint32_t SampleLF(bool verbose, uint32_t sample_size);
 * Initializes the FPGA for sniff-mode (field off), and acquires the samples.
 * @return number of bits sampled
 **/
-uint32_t SniffLF(void);
+uint32_t SniffLF(bool verbose, uint32_t sample_size);
 
 uint32_t DoAcquisition(uint8_t decimation, uint8_t bits_per_sample, bool avg, int16_t trigger_threshold,
                        bool verbose, uint32_t sample_size, uint32_t cancel_after, int32_t samples_to_skip);

client/src/cmdlf.c

@@ -124,12 +124,19 @@ static int usage_lf_sim(void) {
 }
 static int usage_lf_sniff(void) {
     PrintAndLogEx(NORMAL, "Sniff low frequence signal.");
-    PrintAndLogEx(NORMAL, "Usage: lf sniff [h]");
+    PrintAndLogEx(NORMAL, "Usage: lf sniff [h] [q] [s #samples] [@]");
     PrintAndLogEx(NORMAL, "Options:");
     PrintAndLogEx(NORMAL, "       h         This help");
+    PrintAndLogEx(NORMAL, "       q            silent (optional)");
+    PrintAndLogEx(NORMAL, "       s #samples   number of samples to collect (optional)");
+    PrintAndLogEx(NORMAL, "       @            run continuously until a key is pressed (optional)");
+    PrintAndLogEx(NORMAL, "Examples:");
+    PrintAndLogEx(NORMAL, "      lf sniff");
+    PrintAndLogEx(NORMAL, "- oscilloscope style:");
+    PrintAndLogEx(NORMAL, "      data plot");
+    PrintAndLogEx(NORMAL, "      lf sniff q s 3000 @");
     PrintAndLogEx(NORMAL, "Extras:");
     PrintAndLogEx(NORMAL, "  use " _YELLOW_("'lf config'")" to set parameters.");
-    PrintAndLogEx(NORMAL, "  use " _YELLOW_("'data samples'")" command to download from device");
     PrintAndLogEx(NORMAL, "  use " _YELLOW_("'data plot'")" to look at it");
     return PM3_SUCCESS;
 }
@@ -741,18 +748,81 @@ int CmdLFRead(const char *Cmd) {
     return ret;
 }
 
+int lf_sniff(bool verbose, uint32_t samples) {
+    if (!session.pm3_present) return PM3_ENOTTY;
+
+    struct p {
+        uint32_t samples : 31;
+        bool     verbose : 1;
+    } PACKED;
+
+    struct p payload;
+    payload.verbose = verbose;
+    payload.samples = samples;
+
+    clearCommandBuffer();
+    SendCommandNG(CMD_LF_SNIFF_RAW_ADC, (uint8_t *)&payload, sizeof(payload));
+    PacketResponseNG resp;
+    if (g_lf_threshold_set) {
+        WaitForResponse(CMD_LF_SNIFF_RAW_ADC, &resp);
+    } else {
+        if (!WaitForResponseTimeout(CMD_LF_SNIFF_RAW_ADC, &resp, 2500)) {
+            PrintAndLogEx(WARNING, "(lf_read) command execution time out");
+            return PM3_ETIMEOUT;
+        }
+    }
+
+    // response is number of bits read
+    uint32_t size = (resp.data.asDwords[0] / 8);
+    getSamples(size, verbose);
+    return PM3_SUCCESS;
+}
+
 int CmdLFSniff(const char *Cmd) {
 
     if (!session.pm3_present) return PM3_ENOTTY;
 
-    uint8_t cmdp = tolower(param_getchar(Cmd, 0));
+    bool errors = false;
-    if (cmdp == 'h') return usage_lf_sniff();
+    bool verbose = true;
+    bool continuous = false;
+    uint32_t samples = 0;
+    uint8_t cmdp = 0;
+    while (param_getchar(Cmd, cmdp) != 0x00 && !errors) {
+        switch (tolower(param_getchar(Cmd, cmdp))) {
+            case 'h':
+                return usage_lf_sniff();
+            case 's':
+                samples = param_get32ex(Cmd, cmdp + 1, 0, 10);
+                cmdp += 2;
+                break;
+            case 'q':
+                verbose = false;
+                cmdp++;
+                break;
+            case '@':
+                continuous = true;
+                cmdp++;
+                break;
+            default:
+                PrintAndLogEx(WARNING, "Unknown parameter '%c'", param_getchar(Cmd, cmdp));
+                errors = true;
+                break;
+        }
+    }
 
-    clearCommandBuffer();
+    //Validations
-    SendCommandNG(CMD_LF_SNIFF_RAW_ADC, NULL, 0);
+    if (errors) return usage_lf_sniff();
-    WaitForResponse(CMD_ACK, NULL);
+    if (continuous) {
-    getSamples(0, true);
+        PrintAndLogEx(INFO, "Press " _GREEN_("Enter") " to exit");
-    return PM3_SUCCESS;
+    }
+    int ret = PM3_SUCCESS;
+    do {
+        ret = lf_sniff(verbose, samples);
+        if (kbd_enter_pressed()) {
+            break;
+        }
+    } while (continuous);
+    return ret;
 }
 
 static void ChkBitstream(void) {

client/src/cmdlf.h

@@ -33,6 +33,7 @@ int CmdVchDemod(const char *Cmd);
 int CmdLFfind(const char *Cmd);
 
 int lf_read(bool verbose, uint32_t samples);
+int lf_sniff(bool verbose, uint32_t samples);
 int lf_config(sample_config *config);
 int lf_getconfig(sample_config *config);