From 8c40a6b0c74a92754bc3918e35e40072dcc5cc92 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Mon, 26 Sep 2022 22:47:21 -0700
Subject: [PATCH] Drop PS5 Bluetooth reports that fail CRC check
---
src/joystick/hidapi/SDL_hidapi_ps5.c | 73 +++++++++++++++++++++-------
1 file changed, 56 insertions(+), 17 deletions(-)
diff --git a/src/joystick/hidapi/SDL_hidapi_ps5.c b/src/joystick/hidapi/SDL_hidapi_ps5.c
index 1bd1a2669d0..93b59cea1a7 100644
--- a/src/joystick/hidapi/SDL_hidapi_ps5.c
+++ b/src/joystick/hidapi/SDL_hidapi_ps5.c
@@ -45,6 +45,10 @@
#define BLUETOOTH_DISCONNECT_TIMEOUT_MS 500
#define LOAD16(A, B) (Sint16)((Uint16)(A) | (((Uint16)(B)) << 8))
+#define LOAD32(A, B, C, D) ((((Uint32)(A)) << 0) | \
+ (((Uint32)(B)) << 8) | \
+ (((Uint32)(C)) << 16) | \
+ (((Uint32)(D)) << 24))
typedef enum
{
@@ -1256,6 +1260,40 @@ HIDAPI_DriverPS5_HandleStatePacketAlt(SDL_Joystick *joystick, SDL_hid_device *de
SDL_memcpy(&ctx->last_state, packet, sizeof(ctx->last_state));
}
+static SDL_bool
+VerifyCRC(Uint8 *data, int size)
+{
+ Uint8 ubHdr = 0xA1; /* hidp header is part of the CRC calculation */
+ Uint32 unCRC, unPacketCRC;
+ Uint8 *packetCRC = data + size - sizeof(unPacketCRC);
+ unCRC = SDL_crc32(0, &ubHdr, 1);
+ unCRC = SDL_crc32(unCRC, data, (size_t)(size - sizeof(unCRC)));
+
+ unPacketCRC = LOAD32(packetCRC[0],
+ packetCRC[1],
+ packetCRC[2],
+ packetCRC[3]);
+ return (unCRC == unPacketCRC) ? SDL_TRUE : SDL_FALSE;
+}
+
+static SDL_bool
+HIDAPI_DriverPS5_IsPacketValid(SDL_DriverPS5_Context *ctx, Uint8 *data, int size)
+{
+ switch (data[0]) {
+ case k_EPS5ReportIdState:
+ return SDL_TRUE;
+
+ case k_EPS5ReportIdBluetoothState:
+ if (VerifyCRC(data, size)) {
+ return SDL_TRUE;
+ }
+ break;
+ default:
+ break;
+ }
+ return SDL_FALSE;
+}
+
static SDL_bool
HIDAPI_DriverPS5_UpdateDevice(SDL_HIDAPI_Device *device)
{
@@ -1265,25 +1303,18 @@ HIDAPI_DriverPS5_UpdateDevice(SDL_HIDAPI_Device *device)
int size;
int packet_count = 0;
- /* Reconnect the Bluetooth device once the USB device is gone */
- if (device->num_joysticks == 0 &&
- device->is_bluetooth &&
- !HIDAPI_HasConnectedUSBDevice(device->serial)) {
- if (SDL_hid_read_timeout(device->dev, data, sizeof(data), 0) > 0) {
- HIDAPI_JoystickConnected(device, NULL);
- }
- }
-
if (device->num_joysticks > 0) {
joystick = SDL_JoystickFromInstanceID(device->joysticks[0]);
- } else {
- return SDL_FALSE;
}
while ((size = SDL_hid_read_timeout(device->dev, data, sizeof(data), 0)) > 0) {
#ifdef DEBUG_PS5_PROTOCOL
HIDAPI_DumpPacket("PS5 packet: size = %d", data, size);
#endif
+ if (!HIDAPI_DriverPS5_IsPacketValid(ctx, data, size)) {
+ continue;
+ }
+
++packet_count;
ctx->last_packet = SDL_GetTicks();
@@ -1327,15 +1358,23 @@ HIDAPI_DriverPS5_UpdateDevice(SDL_HIDAPI_Device *device)
}
}
- if (device->is_bluetooth && packet_count == 0) {
- /* Check to see if it looks like the device disconnected */
- if (SDL_TICKS_PASSED(SDL_GetTicks(), ctx->last_packet + BLUETOOTH_DISCONNECT_TIMEOUT_MS)) {
- /* Send an empty output report to tickle the Bluetooth stack */
- HIDAPI_DriverPS5_TickleBluetooth(device);
+ if (device->is_bluetooth) {
+ if (packet_count == 0) {
+ /* Check to see if it looks like the device disconnected */
+ if (SDL_TICKS_PASSED(SDL_GetTicks(), ctx->last_packet + BLUETOOTH_DISCONNECT_TIMEOUT_MS)) {
+ /* Send an empty output report to tickle the Bluetooth stack */
+ HIDAPI_DriverPS5_TickleBluetooth(device);
+ }
+ } else {
+ /* Reconnect the Bluetooth device once the USB device is gone */
+ if (device->num_joysticks == 0 &&
+ !HIDAPI_HasConnectedUSBDevice(device->serial)) {
+ HIDAPI_JoystickConnected(device, NULL);
+ }
}
}
- if (size < 0) {
+ if (size < 0 && device->num_joysticks > 0) {
/* Read error, device is disconnected */
HIDAPI_JoystickDisconnected(device, device->joysticks[0]);
}