Reaching max_dump_size does not stop the capture

Now only the PCAP dump is stopped when max_dump_size is reached

app/src/main/java/com/emanuelef/remote_capture/CaptureService.java

@@ -585,8 +585,7 @@ public class CaptureService extends VpnService implements Runnable {
 
         // signal termination
         mPendingUpdates.offer(new Pair<>(null, null));
-        if(mDumpQueue != null)
-            mDumpQueue.offer(new byte[0]);
+        stopPcapDump();
 
         while((mCaptureThread != null) && (mCaptureThread.isAlive())) {
             try {
@@ -615,7 +614,7 @@ public class CaptureService extends VpnService implements Runnable {
                 mDumperThread.join();
             } catch (InterruptedException e) {
                 Log.e(TAG, "Joining dumper thread failed");
-                mDumpQueue.offer(new byte[0]);
+                stopPcapDump();
             }
         }
         mDumperThread = null;
@@ -1005,6 +1004,11 @@ public class CaptureService extends VpnService implements Runnable {
         }
     }
 
+    public void stopPcapDump() {
+        if((mDumpQueue != null) && (mDumperThread != null) && (mDumperThread.isAlive()))
+            mDumpQueue.offer(new byte[0]);
+    }
+
     public void reportError(String msg) {
         mHandler.post(() -> {
             Toast.makeText(this, msg, Toast.LENGTH_LONG).show();

app/src/main/jni/core/jni_impl.c

@@ -112,6 +112,15 @@ static void sendPcapDump(pcapdroid_t *pd) {
 
 /* ******************************************************* */
 
+static void stopPcapDump(pcapdroid_t *pd) {
+    JNIEnv *env = pd->env;
+
+    (*env)->CallVoidMethod(env, pd->capture_service, mids.stopPcapDump);
+    jniCheckException(env);
+}
+
+/* ******************************************************* */
+
 static void notifyServiceStatus(pcapdroid_t *pd, const char *status) {
     JNIEnv *env = pd->env;
     jstring status_str;
@@ -436,6 +445,7 @@ Java_com_emanuelef_remote_1capture_CaptureService_runPacketLoop(JNIEnv *env, jcl
     mids.getApplicationByUid = jniGetMethodID(env, vpn_class, "getApplicationByUid", "(I)Ljava/lang/String;"),
             mids.protect = jniGetMethodID(env, vpn_class, "protect", "(I)Z");
     mids.dumpPcapData = jniGetMethodID(env, vpn_class, "dumpPcapData", "([B)V");
+    mids.stopPcapDump = jniGetMethodID(env, vpn_class, "stopPcapDump", "()V");
     mids.updateConnections = jniGetMethodID(env, vpn_class, "updateConnections", "([Lcom/emanuelef/remote_capture/model/ConnectionDescriptor;[Lcom/emanuelef/remote_capture/model/ConnectionUpdate;)V");
     mids.sendStatsDump = jniGetMethodID(env, vpn_class, "sendStatsDump", "(Lcom/emanuelef/remote_capture/model/VPNStats;)V");
     mids.sendServiceStatus = jniGetMethodID(env, vpn_class, "sendServiceStatus", "(Ljava/lang/String;)V");
@@ -470,6 +480,7 @@ Java_com_emanuelef_remote_1capture_CaptureService_runPacketLoop(JNIEnv *env, jcl
                     .send_stats_dump = sendStatsDump,
                     .send_connections_dump = sendConnectionsDump,
                     .send_pcap_dump = sendPcapDump,
+                    .stop_pcap_dump = stopPcapDump,
                     .notify_service_status = notifyServiceStatus,
                     .notify_blacklists_loaded = notifyBlacklistsLoaded,
             },

app/src/main/jni/core/pcapdroid.c

@@ -875,6 +875,9 @@ static int check_blacklisted_conn_cb(pcapdroid_t *pd, const zdtun_5tuple_t *tupl
 /* ******************************************************* */
 
 static void sendPcapDump(pcapdroid_t *pd) {
+    if(pd->pcap_dump.buffer_idx == 0)
+        return;
+
     if(pd->cb.send_pcap_dump)
         pd->cb.send_pcap_dump(pd);
 
@@ -884,6 +887,17 @@ static void sendPcapDump(pcapdroid_t *pd) {
 
 /* ******************************************************* */
 
+static void stop_pcap_dump(pcapdroid_t *pd){
+    sendPcapDump(pd);
+    pd_free(pd->pcap_dump.buffer);
+    pd->pcap_dump.buffer = NULL;
+
+    if(pd->cb.stop_pcap_dump)
+        pd->cb.stop_pcap_dump(pd);
+}
+
+/* ******************************************************* */
+
 /* Perfom periodic tasks. This should be called after processing a packet or after some time has
  * passed (e.g. after a select with no packet). */
 void pd_housekeeping(pcapdroid_t *pd) {
@@ -1046,8 +1060,8 @@ void pd_account_stats(pcapdroid_t *pd, pkt_context_t *pctx) {
                   JAVA_PCAP_BUFFER_SIZE, pd->pcap_dump.buffer_idx, rec_size);
         else if((pd->pcap_dump.max_dump_size > 0) &&
                 ((pd->pcap_dump.tot_size + rec_size) >= pd->pcap_dump.max_dump_size)) {
-            log_d("Max dump size reached, stopping capture");
-            running = false;
+            log_d("Max dump size reached, stop the dump");
+            stop_pcap_dump(pd);
         } else {
             pcap_dump_rec(pd, (u_char *) pd->pcap_dump.buffer + pd->pcap_dump.buffer_idx,
                           pctx);
@@ -1148,13 +1162,8 @@ int pd_run(pcapdroid_t *pd) {
     ndpi_exit_detection_module(pd->ndpi);
 #endif
 
-    if(pd->pcap_dump.buffer) {
-        if(pd->pcap_dump.buffer_idx > 0)
-            sendPcapDump(pd);
-
-        pd_free(pd->pcap_dump.buffer);
-        pd->pcap_dump.buffer = NULL;
-    }
+    if(pd->pcap_dump.buffer)
+        stop_pcap_dump(pd);
 
     uid_to_app_t *e, *tmp;
     HASH_ITER(hh, pd->uid2app, e, tmp) {

app/src/main/jni/core/pcapdroid.h

@@ -143,6 +143,7 @@ typedef struct {
     void (*send_stats_dump)(struct pcapdroid *pd);
     void (*send_connections_dump)(struct pcapdroid *pd);
     void (*send_pcap_dump)(struct pcapdroid *pd);
+    void (*stop_pcap_dump)(struct pcapdroid *pd);
     void (*notify_service_status)(struct pcapdroid *pd, const char *status);
     void (*notify_blacklists_loaded)(struct pcapdroid *pd, bl_status_arr_t *status_arr);
 } pd_callbacks_t;
@@ -266,6 +267,7 @@ typedef struct {
     jmethodID getApplicationByUid;
     jmethodID protect;
     jmethodID dumpPcapData;
+    jmethodID stopPcapDump;
     jmethodID updateConnections;
     jmethodID connInit;
     jmethodID connProcessUpdate;

docs/app_api.md

@@ -83,10 +83,10 @@ As shown above, the capture settings can be specified by using intent extras. Th
 | ipv6_enabled            | bool   |     | true to enable IPv6 support in non-root mode                       |
 | root_capture            | bool   |     | true to capture packets in root mode, false to use the VPNService  |
 | pcapdroid_trailer       | bool   |     | true to enable the PCAPdroid trailer                               |
-| capture_interface       | string |  42 | @inet \| any \| ifname - network interface to use in root mode     |
+| capture_interface       | string |     | @inet \| any \| ifname - network interface to use in root mode     |
 | snaplen                 | int    |  43 | max size in bytes for each individual packet in the PCAP  dump     |
 | max_pkts_per_flow       | int    |  43 | only dump the first max_pkts_per_flow packets per flow             |
-| max_dump_size           | int    |  43 | PCAP dump max bytes before the capture is automatically stopped    |
+| max_dump_size           | int    |  43 | max size in bytes for the PCAP dump                                |
 
 The `Ver` column indicates the minimum PCAPdroid version required to use the given parameter. The PCAPdroid version can be queried via the `get_status` action as explained below.