[core] add audio channels limit when opening files, configurable through switch.conf.xml (param "max-audio-channels"), add unit-test.

conf/testing/autoload_configs/switch.conf.xml

@@ -191,6 +191,8 @@
     <!-- Allow multiple registrations to the same account in the central registration table -->
     <!-- <param name="multiple-registrations" value="true"/> -->
     
+    <!-- <param name="max-audio-channels" value="2"/> -->
+   
   </settings>
 
 </configuration>

conf/vanilla/autoload_configs/switch.conf.xml

@@ -200,6 +200,8 @@
     <!-- Allow multiple registrations to the same account in the central registration table -->
     <!-- <param name="multiple-registrations" value="true"/> -->
 
+    <!-- <param name="max-audio-channels" value="2"/> -->
+
   </settings>
 
 </configuration>

src/include/private/switch_core_pvt.h

@@ -314,6 +314,7 @@ struct switch_runtime {
 	int events_use_dispatch;
 	uint32_t port_alloc_flags;
 	char *event_channel_key_separator;
+	uint32_t max_audio_channels;
 };
 
 extern struct switch_runtime runtime;

src/include/switch_core.h

@@ -2702,6 +2702,7 @@ SWITCH_DECLARE(const char *) switch_core_banner(void);
 SWITCH_DECLARE(switch_bool_t) switch_core_session_in_thread(switch_core_session_t *session);
 SWITCH_DECLARE(uint32_t) switch_default_ptime(const char *name, uint32_t number);
 SWITCH_DECLARE(uint32_t) switch_default_rate(const char *name, uint32_t number);
+SWITCH_DECLARE(uint32_t) switch_core_max_audio_channels(uint32_t limit);
 
 /*!
  \brief Add user registration

src/switch_core.c

@@ -2383,6 +2383,8 @@ static void switch_load_core_config(const char *file)
 					} else {
 						switch_clear_flag((&runtime), SCF_EVENT_CHANNEL_LOG_UNDELIVERABLE_JSON);
 					}
+				} else if (!strcasecmp(var, "max-audio-channels") && !zstr(val)) {
+					switch_core_max_audio_channels(atoi(val));
 				}
 			}
 		}
@@ -2638,6 +2640,15 @@ SWITCH_DECLARE(int32_t) switch_core_sessions_peak_fivemin(void)
 	return runtime.sessions_peak_fivemin;
 }
 
+SWITCH_DECLARE(uint32_t) switch_core_max_audio_channels(uint32_t limit)
+{
+	if (limit) {
+		runtime.max_audio_channels = limit;
+	}
+
+	return runtime.max_audio_channels;
+}
+
 SWITCH_DECLARE(int32_t) switch_core_session_ctl(switch_session_ctl_t cmd, void *val)
 {
 	int *intval = (int *) val;

src/switch_core_file.c

@@ -76,6 +76,7 @@ SWITCH_DECLARE(switch_status_t) switch_core_perform_file_open(const char *file,
 	char *fp = NULL;
 	int to = 0;
 	int force_channels = 0;
+	uint32_t core_channel_limit;
 
 	if (switch_test_flag(fh, SWITCH_FILE_OPEN)) {
 		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Handle already open\n");
@@ -361,6 +362,19 @@ SWITCH_DECLARE(switch_status_t) switch_core_perform_file_open(const char *file,
 		goto fail;
 	}
 
+	if (fh->channels > 2) {
+		/* just show a warning for more than 2 channels, no matter if we allow them or not */
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "File [%s] has more than 2 channels: [%u]\n", file_path, fh->channels);
+	}
+
+	core_channel_limit = switch_core_max_audio_channels(0);
+	if (core_channel_limit && fh->channels > core_channel_limit) {
+		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "File [%s] has more channels (%u) than limit (%u). Closing.\n", file_path, fh->channels, core_channel_limit);
+		fh->file_interface->file_close(fh);
+		UNPROTECT_INTERFACE(fh->file_interface);
+		switch_goto_status(SWITCH_STATUS_FALSE, fail);
+	}
+
 	if (!force_channels && !fh->real_channels) {
 		fh->real_channels = fh->channels;
 

tests/unit/switch_core_file.c

@@ -185,6 +185,45 @@ FST_CORE_BEGIN("./conf")
 
 		}
 		FST_TEST_END()
+		FST_TEST_BEGIN(test_switch_core_file_open_max_audio_channels)
+		{
+			switch_file_handle_t fh = { 0 };
+			switch_status_t status = SWITCH_STATUS_FALSE;
+			static char filename[] = "/tmp/fs_unit_test.wav";
+			static char hdr[] = /*simplest wav file, hardcoded 8 channels*/
+				"\x52\x49\x46\x46"
+				"\x24\x00\x00\x00"
+				"\x57\x41\x56\x45"
+				"\x66\x6d\x74\x20"
+				"\x10\x00\x00\x00"
+				"\x01\x00\x08\x00"
+				"\x44\xac\x00\x00"
+				"\x88\x58\x01\x00"
+				"\x02\x00\x10\x00"
+				"\x64\x61\x74\x61"
+				"\x00\x00";
+			FILE *f = NULL;
+
+			f = fopen(filename, "w"); 
+			fst_check(f != NULL);
+			fwrite(hdr, 1, sizeof(hdr) ,f);
+			fclose(f);
+
+			switch_core_max_audio_channels(6);
+			status = switch_core_file_open(&fh, filename, 1, 8000, SWITCH_FILE_FLAG_READ | SWITCH_FILE_DATA_SHORT, NULL);
+			fst_check(status == SWITCH_STATUS_FALSE);
+
+			switch_core_max_audio_channels(8);
+			status = switch_core_file_open(&fh, filename, 1, 8000, SWITCH_FILE_FLAG_READ | SWITCH_FILE_DATA_SHORT, NULL);
+			fst_check(status == SWITCH_STATUS_SUCCESS);
+
+			status = switch_core_file_close(&fh);
+			fst_check(status == SWITCH_STATUS_SUCCESS);
+
+			unlink(filename);
+		}
+		FST_TEST_END()
+
 	}
 	FST_SUITE_END()
 }