X-Git-Url: http://git.linex4red.de/pub/USBasp.git/blobdiff_plain/2dabb4e55f1c362f63ef181469f529867ce8b03b..55d7e1e65bccd6b4c44802cf971f39eb05e6e57a:/Demos/Host/Incomplete/BluetoothHost/Lib/RFCOMM.c diff --git a/Demos/Host/Incomplete/BluetoothHost/Lib/RFCOMM.c b/Demos/Host/Incomplete/BluetoothHost/Lib/RFCOMM.c index a57f3a44d..7c39cb028 100644 --- a/Demos/Host/Incomplete/BluetoothHost/Lib/RFCOMM.c +++ b/Demos/Host/Incomplete/BluetoothHost/Lib/RFCOMM.c @@ -61,123 +61,221 @@ const uint8_t CRC8_Table[256] PROGMEM = 0xB4, 0x25, 0x57, 0xC6, 0xB3, 0x22, 0x50, 0xC1, 0xBA, 0x2B, 0x59, 0xC8, 0xBD, 0x2C, 0x5E, 0xCF }; +/** RFCOMM channel state structure, to retain information about each open channel in the RFCOMM multiplexer. */ +RFCOMM_Channel_t RFCOMM_Channels[RFCOMM_MAX_OPEN_CHANNELS]; + + /** Initializes the RFCOMM service, ready for new connections from a SDP client. */ void RFCOMM_Initialize(void) { - /* Not currently used */ + /* Reset the RFCOMM channel structures, to invalidate any confiured RFCOMM channels */ + for (uint8_t i = 0; i < RFCOMM_MAX_OPEN_CHANNELS; i++) + RFCOMM_Channels[i].State = RFCOMM_Channel_Closed; } void RFCOMM_ProcessPacket(void* Data, Bluetooth_Channel_t* const Channel) { - const RFCOMM_Header_t* FrameHeader = (const RFCOMM_Header_t*)Data; + const RFCOMM_Header_t* FrameHeader = (const RFCOMM_Header_t*)Data; + const uint8_t* FrameData = (const uint8_t*)Data + sizeof(RFCOMM_Header_t); + uint16_t FrameDataLen = RFCOMM_GetVariableFieldValue(&FrameData); /* Decode the RFCOMM frame type from the header */ switch (FrameHeader->Control & ~FRAME_POLL_FINAL) { - case RFCOMM_Frame_SABM: - RFCOMM_ProcessSABM(FrameHeader, Channel); - break; - case RFCOMM_Frame_UA: - RFCOMM_ProcessUA(FrameHeader, Channel); - break; case RFCOMM_Frame_DM: - RFCOMM_ProcessDM(FrameHeader, Channel); + RFCOMM_ProcessDM(&FrameHeader->Address, Channel); break; case RFCOMM_Frame_DISC: - RFCOMM_ProcessDISC(FrameHeader, Channel); + RFCOMM_ProcessDISC(&FrameHeader->Address, Channel); + break; + case RFCOMM_Frame_SABM: + RFCOMM_ProcessSABM(&FrameHeader->Address, Channel); + break; + case RFCOMM_Frame_UA: + RFCOMM_ProcessUA(&FrameHeader->Address, Channel); break; case RFCOMM_Frame_UIH: - RFCOMM_ProcessUIH(FrameHeader, Channel); + RFCOMM_ProcessUIH(&FrameHeader->Address, FrameDataLen, FrameData, Channel); break; default: - BT_RFCOMM_DEBUG(1, "<< Unknown Frame Type"); + BT_RFCOMM_DEBUG(1, "<< Unknown Frame Received"); break; } } -static void RFCOMM_ProcessSABM(const RFCOMM_Header_t* const FrameHeader, Bluetooth_Channel_t* const Channel) +RFCOMM_Channel_t* RFCOMM_GetChannelData(const uint8_t DLCI) { - BT_RFCOMM_DEBUG(1, "<< SABM Received"); - BT_RFCOMM_DEBUG(2, "-- Address 0x%02X", FrameHeader->Address); + /* Search through the RFCOMM channel list, looking for the specified channel */ + for (uint8_t i = 0; i < RFCOMM_MAX_OPEN_CHANNELS; i++) + { + RFCOMM_Channel_t* CurrRFCOMMChannel = &RFCOMM_Channels[i]; - // TODO: Reset channel send/receive state here + /* If the current non-closed channel's DLCI matches the search DLCI, return it to the caller */ + if ((CurrRFCOMMChannel->DLCI == DLCI) && (CurrRFCOMMChannel->State != RFCOMM_Channel_Closed)) + return CurrRFCOMMChannel; + } + + /* Channel not found in the channel state table, return failure */ + return NULL; +} + +uint16_t RFCOMM_GetVariableFieldValue(const uint8_t** BufferPos) +{ + uint8_t FirstOctet; + uint8_t SecondOctet = 0; + + FirstOctet = **BufferPos; + (*BufferPos)++; + /* If the field size is more than a single byte, fetch the next byte in the variable length field */ + if (!(FirstOctet & 0x01)) + { + SecondOctet = **BufferPos; + (*BufferPos)++; + + /* Discard any remaining bytes in the variable length field that won't fit in the return value */ + while (!(**BufferPos & 0x01)) + (*BufferPos)++; + } + + /* Bitshift the bytes that comprise the variable length field so that they form a single integer */ + return (((uint16_t)SecondOctet << 7) | FirstOctet >> 1); +} + +void RFCOMM_SendFrame(const uint8_t DLCI, const bool CommandResponse, const uint8_t Control, const uint16_t DataLen, + const void* Data, Bluetooth_Channel_t* const Channel) +{ struct { RFCOMM_Header_t FrameHeader; - uint8_t FrameLength; + uint8_t Size[(DataLen < 128) ? 1 : 2]; + uint8_t Data[DataLen]; uint8_t FCS; } ResponsePacket; - /* Copy over the same frame header as the sent packet to copy the logical RFCOMM channel address */ - ResponsePacket.FrameHeader.Address = FrameHeader->Address; + /* Set the frame header values to the specified address and frame type */ + ResponsePacket.FrameHeader.Control = Control; + ResponsePacket.FrameHeader.Address = (RFCOMM_Address_t) + { + .EA = true, + .CR = CommandResponse, + .DLCI = DLCI, + }; - /* Set the frame type to an Unnumbered Acknowledgement to acknowledge the SABM request */ - ResponsePacket.FrameHeader.Control = RFCOMM_Frame_UA; + /* Set the lower 7 bits of the packet length */ + ResponsePacket.Size[0] = (DataLen << 1); - /* Set the length to 0 (LSB indicates end of 8-bit length field) */ - ResponsePacket.FrameLength = 0x01; + /* Terminate the size field if size is 7 bits or lower, otherwise set the upper 8 bits of the length */ + if (DataLen < 128) + ResponsePacket.Size[0] |= 0x01; + else + ResponsePacket.Size[1] = (DataLen >> 7); - /* Calculate the frame checksum from all fields except the FCS field itself */ - ResponsePacket.FCS = RFCOMM_GetFCSValue(&ResponsePacket, sizeof(ResponsePacket) - sizeof(ResponsePacket.FCS)); + /* Copy over the packet data from the source buffer to the response packet buffer */ + memcpy(ResponsePacket.Data, Data, DataLen); - BT_RFCOMM_DEBUG(1, ">> UA Sent"); + /* Determine the length of the frame which is to be used to calculate the CRC value */ + uint8_t CRCLength = sizeof(ResponsePacket.FrameHeader); + + /* UIH frames do not have the CRC calculated on the Size field in the response, all other frames do */ + if ((Control & ~FRAME_POLL_FINAL) != RFCOMM_Frame_UIH) + CRCLength += sizeof(ResponsePacket.Size); + + /* Calculate the frame checksum from the appropriate fields */ + ResponsePacket.FCS = RFCOMM_GetFCSValue(&ResponsePacket, CRCLength); /* Send the completed response packet to the sender */ Bluetooth_SendPacket(&ResponsePacket, sizeof(ResponsePacket), Channel); } -static void RFCOMM_ProcessUA(const RFCOMM_Header_t* const FrameHeader, Bluetooth_Channel_t* const Channel) +static uint8_t RFCOMM_GetFCSValue(const void* FrameStart, uint8_t Length) { - const uint8_t* CurrBufferPos = ((const uint8_t*)FrameHeader + sizeof(RFCOMM_Header_t)); + uint8_t FCS = 0xFF; + + for (uint8_t i = 0; i < Length; i++) + FCS = pgm_read_byte(&CRC8_Table[FCS ^ ((uint8_t*)FrameStart)[i]]); - BT_RFCOMM_DEBUG(1, "<< UA Received"); - BT_RFCOMM_DEBUG(2, "-- Address 0x%02X", FrameHeader->Address); + return ~FCS; } -static void RFCOMM_ProcessDM(const RFCOMM_Header_t* const FrameHeader, Bluetooth_Channel_t* const Channel) +static void RFCOMM_ProcessDM(const RFCOMM_Address_t* const FrameAddress, Bluetooth_Channel_t* const Channel) { - const uint8_t* CurrBufferPos = ((const uint8_t*)FrameHeader + sizeof(RFCOMM_Header_t)); - BT_RFCOMM_DEBUG(1, "<< DM Received"); - BT_RFCOMM_DEBUG(2, "-- Address 0x%02X", FrameHeader->Address); + BT_RFCOMM_DEBUG(2, "-- DLCI 0x%02X", FrameAddress->DLCI); } -static void RFCOMM_ProcessDISC(const RFCOMM_Header_t* const FrameHeader, Bluetooth_Channel_t* const Channel) +static void RFCOMM_ProcessDISC(const RFCOMM_Address_t* const FrameAddress, Bluetooth_Channel_t* const Channel) { - const uint8_t* CurrBufferPos = ((const uint8_t*)FrameHeader + sizeof(RFCOMM_Header_t)); - BT_RFCOMM_DEBUG(1, "<< DISC Received"); - BT_RFCOMM_DEBUG(2, "-- Address 0x%02X", FrameHeader->Address); -} + BT_RFCOMM_DEBUG(2, "-- DLCI 0x%02X", FrameAddress->DLCI); -static void RFCOMM_ProcessUIH(const RFCOMM_Header_t* const FrameHeader, Bluetooth_Channel_t* const Channel) -{ - const uint8_t* CurrBufferPos = ((const uint8_t*)FrameHeader + sizeof(RFCOMM_Header_t)); + RFCOMM_Channel_t* RFCOMMChannel = RFCOMM_GetChannelData(FrameAddress->DLCI); + + /* If the requested channel is currently open, destroy it */ + if (RFCOMMChannel != NULL) + RFCOMMChannel->DLCI = 0x00; - BT_RFCOMM_DEBUG(1, "<< UIH Received"); - BT_RFCOMM_DEBUG(2, "-- Address 0x%02X", FrameHeader->Address); + BT_RFCOMM_DEBUG(1, ">> UA Sent"); + RFCOMM_SendFrame(FrameAddress->DLCI, true, (RFCOMM_Frame_UA | FRAME_POLL_FINAL), 0, NULL, Channel); } -static uint8_t RFCOMM_GetFCSValue(const void* FrameStart, uint16_t Length) +static void RFCOMM_ProcessSABM(const RFCOMM_Address_t* const FrameAddress, Bluetooth_Channel_t* const Channel) { - const uint8_t* CurrPos = FrameStart; - uint8_t FCS = 0xFF; + BT_RFCOMM_DEBUG(1, "<< SABM Received"); + BT_RFCOMM_DEBUG(2, "-- DLCI 0x%02X", FrameAddress->DLCI); + + /* Find a free entry in the RFCOMM channel multiplexer state array */ + for (uint8_t i = 0; i < RFCOMM_MAX_OPEN_CHANNELS; i++) + { + RFCOMM_Channel_t* CurrRFCOMMChannel = &RFCOMM_Channels[i]; - while (Length--) - FCS = pgm_read_byte(CRC8_Table[FCS ^ *(CurrPos++)]); + /* If the channel's DLCI is zero, the channel state entry is free */ + if (!(CurrRFCOMMChannel->DLCI)) + { + CurrRFCOMMChannel->DLCI = FrameAddress->DLCI; + CurrRFCOMMChannel->State = RFCOMM_Channel_Open; + CurrRFCOMMChannel->Priority = 7 + (CurrRFCOMMChannel->DLCI >> 3) + ((CurrRFCOMMChannel->DLCI >> 3) * 7); + CurrRFCOMMChannel->MTU = 0xFFFF; + CurrRFCOMMChannel->Remote.Signals = 0 | (1 << 0); + CurrRFCOMMChannel->Remote.BreakSignal = 0 | (1 << 0); + CurrRFCOMMChannel->Local.Signals = RFCOMM_SIGNAL_RTC | RFCOMM_SIGNAL_RTR | RFCOMM_SIGNAL_DV | (1 << 0); + CurrRFCOMMChannel->Local.BreakSignal = 0 | (1 << 0); + + BT_RFCOMM_DEBUG(1, ">> UA Sent"); + RFCOMM_SendFrame(FrameAddress->DLCI, true, (RFCOMM_Frame_UA | FRAME_POLL_FINAL), 0, NULL, Channel); + return; + } + } - return ~FCS; + BT_RFCOMM_DEBUG(1, ">> DM Sent"); + + /* No free channel in the multiplexer - decline the SABM by sending a DM frame */ + RFCOMM_SendFrame(FrameAddress->DLCI, true, (RFCOMM_Frame_DM | FRAME_POLL_FINAL), 0, NULL, Channel); } -static uint16_t RFCOMM_GetFrameDataLength(const uint8_t** BufferPos) +static void RFCOMM_ProcessUA(const RFCOMM_Address_t* const FrameAddress, Bluetooth_Channel_t* const Channel) { - uint8_t FirstOctet = *((*BufferPos)++); - uint8_t SecondOctet = 0; + BT_RFCOMM_DEBUG(1, "<< UA Received"); + BT_RFCOMM_DEBUG(2, "-- DLCI 0x%02X", FrameAddress->DLCI); +} + +static void RFCOMM_ProcessUIH(const RFCOMM_Address_t* const FrameAddress, const uint16_t FrameLength, + const uint8_t* FrameData, Bluetooth_Channel_t* const Channel) +{ + if (FrameAddress->DLCI == RFCOMM_CONTROL_DLCI) + { + RFCOMM_ProcessControlCommand(FrameData, Channel); + return; + } + + BT_RFCOMM_DEBUG(1, "<< UIH Received"); + BT_RFCOMM_DEBUG(2, "-- DLCI 0x%02X", FrameAddress->DLCI); + BT_RFCOMM_DEBUG(2, "-- Length 0x%02X", FrameLength); + + puts("RFCOMM Data: "); - if (!(FirstOctet & 0x01)) - SecondOctet = *((*BufferPos)++); + for (uint8_t i = 0; i < FrameLength; i++) + printf("0x%02X (%c) ", FrameData[i], FrameData[i]); - return (((uint16_t)SecondOctet << 7) | (FirstOctet >> 1)); + printf("\r\n"); } -