Test version of BlueUSB stack. Includes SDP and RFCOMM. As Client it allows to connect to my fischertechnik TX Controller. As Server it echo\\\\\\\'s characters to Putty. PIN=1234
Dependencies: mbed myUSBHost AvailableMemory
Dependents: mbed_TANK_Kinect myBlueUSB_ros ftusbClass
L2CAP.cpp
- Committer:
- networker
- Date:
- 2011-06-19
- Revision:
- 12:57f7679dd651
- Parent:
- 10:1928a3d02e32
File content as of revision 12:57f7679dd651:
/* Copyright (c) 2010 Peter Barrett Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ #include <stdio.h> #include <stdlib.h> #include <stdio.h> #include <string.h> #include "Utils.h" #include "hci.h" #include "HCITransportUSB.h" #include "sdp.h" #include "RFCOMM.h" #define L2CAP_COMMAND_REJ 0x01 #define L2CAP_CONN_REQ 0x02 #define L2CAP_CONN_RSP 0x03 #define L2CAP_CONF_REQ 0x04 #define L2CAP_CONF_RSP 0x05 #define L2CAP_DISCONN_REQ 0x06 #define L2CAP_DISCONN_RSP 0x07 #define L2CAP_ECHO_REQ 0x08 #define L2CAP_ECHO_RSP 0x09 #define L2CAP_INFO_REQ 0x0a #define L2CAP_INFO_RSP 0x0b #define TXID (++_txid?_txid:1) //template <class T> T min(T a, T b) { return a<b ? a : b;} /* L2CAP command codes */ const char* L2CAP_ComandCodeStr(int c) { switch (c) { case L2CAP_COMMAND_REJ: return "L2CAP_COMMAND_REJ"; case L2CAP_CONN_REQ: return "L2CAP_CONN_REQ"; case L2CAP_CONN_RSP: return "L2CAP_CONN_RSP"; case L2CAP_CONF_REQ: return "L2CAP_CONF_REQ"; case L2CAP_CONF_RSP: return "L2CAP_CONF_RSP"; case L2CAP_DISCONN_REQ: return "L2CAP_DISCONN_REQ"; case L2CAP_DISCONN_RSP: return "L2CAP_DISCONN_RSP"; case L2CAP_ECHO_REQ: return "L2CAP_ECHO_REQ"; case L2CAP_ECHO_RSP: return "L2CAP_ECHO_RSP"; case L2CAP_INFO_REQ: return "L2CAP_INFO_REQ"; case L2CAP_INFO_RSP: return "L2CAP_INFO_RSP"; } return "unknown"; } #define OFFSET 8 //means the buffer also has space for the l2cap/hci headers and need not be allocated and copied //#define OFFSET 0 //means the buffer only has space for the payload which need to be copied #if OFFSET == 0 #define L2CAPBUFSIZE 128 #else #define L2CAPBUFSIZE 0 #endif typedef struct { u16 handle; u16 length; // total u16 l2capLength; // length -4 u16 cid; // Signaling packet CID = 1 u8 data[L2CAPBUFSIZE]; // Largest thing to send!!! todo } L2CAPData; // void BTDevice::Init() { memset(&_info,0,sizeof(inquiry_info)); _handle = 0; _name[0] = 0; _state = 0; _txid = 1; //cntr_cred = 1; } // virtual SocketHandler int BTDevice::Open(SocketInternal* sock, SocketAddrHdr* addr) { L2CAPSocket* s = (L2CAPSocket*)sock; L2CAPAddr* a = (L2CAPAddr*)addr; s->scid = 0x40 + sock->ID-1; // are these reserved? s->dcid = 0; Connect(s->scid,a->psm); sock->State = SocketState_L2CAP_WaitConnectRsp; contState = 0; return sock->ID; } // virtual SocketHandler int BTDevice::Accept(SocketInternal* sock, int scid, int rxid) { L2CAPSocket* s = (L2CAPSocket*)sock; s->scid = 0x40 + sock->ID-1; // are these reserved? s->dcid = scid; u16 p[4]; p[0] = s->scid; p[1] = scid; p[2] = 0; //success p[3] = 0; //no further information Send(L2CAP_CONN_RSP,rxid,p,4); printf("send conn_rsp with dcid=%#x and scid=%#x\n", p[0],p[1]); sock->State = SocketState_L2CAP_Config_wait; contState = 0; return sock->ID; } // virtual SocketHandler, called from HCI which is ABOVE L2CAP int BTDevice::Send(SocketInternal* sock, const u8* data, int len) { L2CAPSocket* s = (L2CAPSocket*)sock; #if OFFSET == 8 //sizeof L2CAPData header L2CAPData &d = *const_cast<L2CAPData*>((L2CAPData*)data); #else L2CAPData d; #endif if (len > peer_mtu) {//mtu concerns the l2cap mtu, because we use basic mode we cannot segment printf("MTU (%d) for outgoing packet (%d) exceeded\n", peer_mtu, len); return 0; } d.handle = _handle | 0x2000; d.length = 4 + len - OFFSET; d.l2capLength = len - OFFSET; d.cid = s->dcid; //printf("cid=%d: ", d.cid); //printfBytes("sending: ", data, len); #if OFFSET == 0 if (len > L2CAPBUFSIZE) return -1; memcpy(d.data,data,len); return Send((u8*)&d,len+8); #else return Send(data, len); #endif } // virtual SocketHandler int BTDevice::Close(SocketInternal* sock) { printf("L2CAP close %d\n",sock->ID); sock->State = SocketState_L2CAP_WaitDisconnect; L2CAPSocket* s = (L2CAPSocket*)sock; return Disconnect(s->scid,s->dcid); } L2CAPSocket* BTDevice::SCIDToSocket(int scid) { return (L2CAPSocket*)GetSocketInternal(scid-0x40+1); } int BTDevice::Send(const u8* data, int len) {//printfBytes("Transport : ", data, len); #ifdef HOST_CONTR_FLOW pkts_sent++; #endif _transport->ACLSend(data,len); return 0; } void BTDevice::repeat_cmd() { printf("Cmd on handle %#x timed out, resending txid=%d\n", _handle, last_req.id); // Send ((u8*)&last_req, last_req.length+4);//danger! interrupt context, Send is not reentrant //optionally set new larger timeout } int BTDevice::Send(u8 c, u8 id, u16* params, int count) { L2CAPCmd cmd; cmd.handle = _handle | 0x2000; cmd.length = 8 + count*2; cmd.l2capLength = cmd.length-4; cmd.cid = 1; // Signaling packet cmd.cmd = c; cmd.id = id; cmd.cmdLength = count*2; for (int i = 0; i < count; i++) cmd.params[i] = params[i]; if ((c & 1) == 0) { //this is a request last_req = cmd; rtx.attach(this, &BTDevice::repeat_cmd, 30.0); //printf("Starting timeout for %#x, txid=%d\n", _handle, id); } return Send((u8*)&cmd,cmd.length+4); } int BTDevice::Connect(int scid, int psm) { u16 p[2]; p[0] = psm; p[1] = scid; return Send(L2CAP_CONN_REQ,TXID,p,2); } int BTDevice::Disconnect(int scid, int dcid) { u16 p[2]; p[0] = dcid; p[1] = scid; return Send(L2CAP_DISCONN_REQ,TXID,p,2); } int BTDevice::ConfigureRequest(int dcid) { u16 p[4]; p[0] = dcid; p[1] = 0; p[2] = 0x0201; // Options p[3] = min(0x02A0, MAX_ACL_SIZE); // my receiving MTU 672 return Send(L2CAP_CONF_REQ,TXID,p,4); } int BTDevice::CommandReject(u16 reason, u16 data0, u16 data1) { u16 p[3]; p[0] = reason; p[1] = data0; p[2] = data1; int parlen = 2; switch (reason) { case 0: //command not understood break; case 1: //MTU exceeded parlen = 4; //return actual mtu in data break; case 2: //invalid CID parlen = 6; //return local, remote cid break; } return Send(L2CAP_COMMAND_REJ,TXID,p,parlen); } int BTDevice::ConfigureResponse(u8 rxid, int dcid) { u16 p[3]; p[0] = dcid; //source cid p[1] = 0; //flags (no continuation) p[2] = 0; //result (success) return Send(L2CAP_CONF_RSP,rxid,p,3); } int BTDevice::DisconnectResponse(u8 rxid, int scid, int dcid) { u16 p[2]; p[0] = dcid; p[1] = scid; return Send(L2CAP_DISCONN_RSP,rxid,p,2); } void server(int socket, SocketState state, const u8* data, int len, void* userData) { // printfBytes("Server: ", data, len); if (state==SocketState_Open && len>0) SDP.SDPServer(socket, state, data, len, userData); } void serserver(int socket, SocketState state, const u8* data, int len, void* userData) { printfBytes("serserver: ", data, len); SocketHandler *h = (SocketHandler*)userData; printf("userData refers to %s, state = %d\n", h->Name(), state); if (state==SocketState_Open) { if (len == 0) { //assume that the socket has just been opened and bind it to a new rfcomm server entity printf("Calling RFCOMMManager::BindSocket\n"); rfcomm_manager.BindSocket(socket); } else { printf("Calling RFCOMMManager::SerServer\n"); rfcomm_manager.SerServer(socket, state, data, len, userData); } } else if (state==SocketState_L2CAP_WaitDisconnect) { printf("Calling RFCOMMManager::SerServer\n"); rfcomm_manager.SerServer(socket, state, data, len, userData); } } //code8, tid8, lengthData16 // 0, 1, 2, 3 void BTDevice::Control(const u8* data, int len) { //control channel receive printf("\x1B[%dm", 31); int cc = data[0];//command code if (cc & 1) { //it is a response or a reject rtx.detach(); //kill the timeout //printf("timeout cancelled for handle %#x, txid=%d\n", _handle, data[1]); } printf(L2CAP_ComandCodeStr(cc)); switch (cc) { case L2CAP_COMMAND_REJ://bad command, eg. MTU, check (reason) printf(" rejection reason=%d\n", LE16(data+4)); break; case L2CAP_CONN_REQ://incoming connection request, not expected but should reply with proper rejection (or accept) //when a connection is accepted a new socket must be opened printf(" Remote side requested a connection\n"); { int scid = LE16(data+6); int psm = LE16(data+4); int rxid = data[1]; u16 p[4]; p[0] = 0; //no dcid p[1] = scid; p[3] = 0; //no further information printf(" scid=%d, psm=%d\n", scid, psm); peer_mtu = 672; //default mtu int s = 0; switch (psm) { case L2CAP_PSM_SDP: s = Socket_Accept(SOCKET_SDP, scid, rxid, server, this);//allocate an sdp socket but use it as L2CAP break; case L2CAP_PSM_RFCOMM: //SOCKET_RFCOM; #if 0 s = Socket_Accept(SOCKET_RFCOM, scid, rxid, serserver, this);//allocate an rfcomm socket //using L2CAP i.o. RFCOM makes little difference in processing but it also changes the handler to HCI i.o. RFCOMMManager #else //an RFCOMM requests comes in from a known (this) device //the channel is not yet known s = rfcomm_manager.FindSocket(this);//this should return 0 otherwise the remote device was asking a second rfcomm on the same device if (s==0) { printf("No connection to this device yet, allocate L2CAP Socket and accept\n"); //accept the connection, even though there may be no listener??? //have no choice because w/o acceptance no rfcomm req. s = Socket_Accept(SOCKET_L2CAP, scid, rxid, serserver, this);//allocate an l2cap socket //get a new l2cap socket, call HCI::Accept (fill in btdevice internals), then call BTDevice::Accept (send accept message) //serserver is called on state changes (SocketInternal::SetState) and on received packets from the peer device to the new l2cap handle //after sending the accept message, the devices will execute the normal l2cap connection state-machine //ending in a call to SetState(Open) which will invoke 'serserver' for the first time //or something like: // s = Socket_Create(SOCKET_L2CAP, serserver, this);//allocate an l2cap socket // Accept(GetSocketInternal(s), scid, rxid);//send accept response, this would bypass HCI::Accept() } else { printf("Already had an L2CAP connection on socket %d\n", s); } #endif break; default: printf("PSM %d not supported\n", psm); } switch (s) { case 0: printf("Not a valid socket\n"); break; case ERR_SOCKET_TYPE_NOT_FOUND: p[2] = 2; //psm not supported Send(L2CAP_CONN_RSP,rxid,p,4); break; case ERR_SOCKET_NONE_LEFT: p[2] = 4; //no resources available Send(L2CAP_CONN_RSP,rxid,p,4); break; } } break; // Response to our initial connect from Remote case L2CAP_CONN_RSP: { int dcid = LE16(data+4); int scid = LE16(data+6); L2CAPSocket* s = SCIDToSocket(scid); int result = LE16(data+8); printf(" Result=%d, Status = %d\n", result, LE16(data+10)); if (s->si.State != SocketState_L2CAP_WaitConnectRsp) { printf("Unexpected event ignored\n"); break; } if (result == 0) { if (s) { s->si.State = SocketState_L2CAP_Config_wait; s->dcid = dcid; ConfigureRequest(dcid); s->si.State = SocketState_L2CAP_Config_wait_reqrsp; printf("Sent ConfigureRequest, state=WAIT_CONFIG_REQ_RSP\n"); } } else if (result == 1) {//pending, stay in the present state } else { s->si.SetState(SocketState_Closed); printf("Connect failed\n"); } } break; case L2CAP_CONF_RSP: { int result = LE16(data+8); printf("Result=%d, datalen=%d, %smore conf to follow\n", result, LE16(data+2), LE16(data+6)?"":"No "); //should parse the config printfBytes("CONF RSP:", data, LE16(data+2)+4); int scid = LE16(data+4); SocketInternal* s = (SocketInternal*)SCIDToSocket(scid); if (s == 0) break; if (s->State != SocketState_L2CAP_Config_wait_reqrsp && s->State != SocketState_L2CAP_Config_wait_rsp) { printf("Unexpected event ignored\n"); break; } if (result == 0) { //configuration acceptable if (s->State == SocketState_L2CAP_Config_wait_reqrsp) { s->State = SocketState_L2CAP_Config_wait_req; printf("State=WAIT_CONFIG_REQ\n"); } else { ConfigureResponse(data[1],((L2CAPSocket*)s)->dcid);//data[1]==txid printf("Sent ConfigureResponse, state=Open\n"); s->SetState(SocketState_Open); } } else { printf("Renegotiate configuration\n"); } } break; case L2CAP_CONF_REQ: { int len = LE16(data+2); int scid = LE16(data+4);//flags (data[6] LSB is continuation flag, data[10],[11] are the MTU int flags = LE16(data+6); const u8* conf = data+8; if (flags) printf("Warning! Continuation flag in L2CAP configuration not supported\n"); L2CAPSocket* s = SCIDToSocket(scid); printfBytes("CONF REQ: ", data, LE16(data+2)+4);//data+8 contains option type 1-4 1=MTU, 2=flush timeout, 3=QoS, 4=FCM if (s == 0) break; if (s->si.State == SocketState_Closed || s->si.State == SocketState_L2CAP_WaitConnectRsp || s->si.State == SocketState_L2CAP_WaitDisconnect) { //Send Reject command printf("Connection should be rejected\n"); break; } #if 0 if (len > 4) switch (data[8]) { case 1: peer_mtu = LE16(data+10); printf("Peer L2CAP MTU = %d bytes\n", peer_mtu); break; case 2: //flush timeout case 3: //QOS case 4: //retrans and FC option default: printf("Unsupported configuration option %d, value = %#X\n", data[8], LE16(data+10)); break; } else printf("Empty config req. peer_mtu = %d\n", peer_mtu); #else while (conf < data+len+4) { bool hint = conf[0] & 0x80; switch (conf[0] & 0x7F) { case 1: peer_mtu = LE16(conf+2); printf("Peer L2CAP MTU = %d bytes\n", peer_mtu); break; case 2: //flush timeout case 3: //QOS case 4: //retrans and FC option default: printf("Unsupported configuration option %d, value = %#X\n", conf[0], LE16(conf+2)); break; } conf += conf[1]+2; } #endif if (1 /* options acceptable */) { if (flags == 0) { printf("Sending ConfigureResponse, old state=%d ", s->si.State); ConfigureResponse(data[1],s->dcid);//data[1]==txid, success switch (s->si.State) { case SocketState_L2CAP_Config_wait: s->si.State = SocketState_L2CAP_Config_wait_send; ConfigureRequest(s->dcid); s->si.State = SocketState_L2CAP_Config_wait_rsp; break; case SocketState_L2CAP_Config_wait_req: ((SocketInternal*)s)->SetState(SocketState_Open); break; case SocketState_L2CAP_Config_wait_rsp: break; case SocketState_L2CAP_Config_wait_reqrsp: s->si.State = SocketState_L2CAP_Config_wait_rsp; break; } printf("new state=%d\n", s->si.State); } else printf("L2CAP config continuation, delaying response...\n"); } else { //options not acceptable printf("Configure failure should be indicated\n"); ConfigureResponse(data[1],s->dcid);//indicates success but should indicate fail } } break; case L2CAP_DISCONN_REQ: { int dcid = LE16(data+4); int scid = LE16(data+6); L2CAPSocket* s = SCIDToSocket(dcid); if (s) { s->si.SetState(SocketState_Closed); DisconnectResponse(data[1], scid, dcid); } else { printf("request to disconnect cid %d fails, no such cid\n", dcid); CommandReject(0, dcid, scid); } } break; case L2CAP_DISCONN_RSP: { int scid = LE16(data+6); L2CAPSocket* s = SCIDToSocket(scid); if (s->si.State == SocketState_L2CAP_WaitDisconnect) s->si.SetState(SocketState_Closed); } break; default: printf("Unsupported L2CAP message %d\n", cc); } printf("\x1b[0m"); } void BTDevice::ACLFwd(const u8* data, int len) { if (l2cap_sock == 1) Control(data, len); else { SocketInternal* s = (SocketInternal*)SCIDToSocket(l2cap_sock);//in fact cid in the l2cap header if (s) s->Recv(data,len);//forward to the sockethandler for the type else printf("Bad event cid %d\n",l2cap_sock); } } //sometimes acl packets are segmented, in that case the l2cap payload length does not correspond to the acl pkt length //and the l2cap packet length. L2CAP works in basic mode and cannot be segmented hence the l2cap pkt size corresponds to //the acl pkt size int BTDevice::ACLRecv(const u8* data, int acllen) { //printfBytes("L2CP",data,acllen); //cntr_cred--; u16 handle = LE16(data); if ((handle&0x0fff) != _handle) { printf("unexpected handle %#x, this _handle=%#x\n", handle, _handle); return 1; } //below is the ACL packet recombination engine char pb = (handle>>12) & 3; if (pb == 2) segments = 1; else segments++; int p = 4; //start of l2cap packet int len = LE16(data+2); //length of l2cap pkt while (p < acllen) switch (contState) { case 0://allow even for fragmented length field plen = data[p++];//payload length lsb contState = 1; break; case 1: plen += data[p++]<<8; //payload length msb if (pb == 2 && plen == acllen-8) {//normal case, l2cap pkt is contained completely in this hci pkt l2cap_sock = data[p] + (data[p+1]<<8); contState = 0; ACLFwd(data+8, plen); //forward the packet in its original buffer return segments; //all data was dealt with } else { //packet is segmented printf("ACL packet is segmented\n"); contState = 2; contBuf = new unsigned char[plen];//allocate recombination buffer contPos = 0; } break; case 2: l2cap_sock = data[p++]; contState = 3; break; case 3: l2cap_sock += data[p++]<<8; contState = 4; break; case 4: //data, recombine segmented ACL (not l2cap!) frames if (contPos < plen) {//buffer not yet full int datalen = acllen - p; //data in this incoming pkt int remcap = plen - contPos; //remaining capacity in the recombination buffer if (datalen <= remcap) { memcpy(contBuf+contPos, data+p, datalen); contPos += datalen; p = acllen;//end of data, stop the while loop if (contPos == plen) {//buffer is full now printfBytes("Recombined packet is:", contBuf, plen); ACLFwd(contBuf, plen); //forward the recombination buffer delete[] contBuf;//and free the buffer contState = 0; return segments; }//else stay in this state to wait for the rest } else {//data contains (part of) next packet, never seen this happen memcpy(contBuf+contPos, data+p, plen-contPos);//this packet is complete p += plen-contPos; printfBytes("Recombined packet is:", contBuf, plen); printfBytes("Next packet starts with:", data+p, acllen-p); ACLFwd(contBuf, plen); //forward the recombination buffer delete[] contBuf;//and free the buffer contState = 0; //continue with the next packet } } else { printf("Cannot append to buffer (size=%d, pos=%d, datalen = %d)\n", plen, contPos, len-p); contState = 0; return segments;//flushed } break; }//switch (and while) return 0;//the buffers are not processed yet }