resource/csdk/connectivity/src/tcp_adapter/catcpserver.c

   1 /* ****************************************************************j
   2  *
   3  * Copyright 2015 Samsung Electronics All Rights Reserved.
   4  *
   5  *
   6  *
   7  * Licensed under the Apache License, Version 2.0 (the "License");
   8  * you may not use this file except in compliance with the License.
   9  * You may obtain a copy of the License at
  10  *
  11  *      http://www.apache.org/licenses/LICENSE-2.0
  12  *
  13  * Unless required by applicable law or agreed to in writing, software
  14  * distributed under the License is distributed on an "AS IS" BASIS,
  15  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  16  * See the License for the specific language governing permissions and
  17  * limitations under the License.
  18  *
  19  ******************************************************************/
  20
  21 #include <sys/types.h>
  22 #include <sys/socket.h>
  23 #include <sys/ioctl.h>
  24 #include <stdio.h>
  25 #include <unistd.h>
  26 #include <sys/types.h>
  27 #include <fcntl.h>
  28 #include <sys/select.h>
  29 #include <arpa/inet.h>
  30 #include <netinet/in.h>
  31 #include <net/if.h>
  32 #include <errno.h>
  33 #include <sys/poll.h>
  34
  35 #ifndef WITH_ARDUINO
  36 #include <sys/socket.h>
  37 #include <netinet/in.h>
  38 #include <netdb.h>
  39 #endif
  40
  41 #include "catcpinterface.h"
  42 #include "pdu.h"
  43 #include "caadapterutils.h"
  44 #include "camutex.h"
  45 #include "oic_malloc.h"
  46 #include "oic_string.h"
  47
  48 /**
  49  * Logging tag for module name.
  50  */
  51 #define TAG "OIC_CA_TCP_SERVER"
  52
  53 /**
  54  * Server port number for local test.
  55  */
  56 #define SERVER_PORT 8000
  57
  58 /**
  59  * Maximum CoAP over TCP header length
  60  * to know the total data length.
  61  */
  62 #define TCP_MAX_HEADER_LEN  6
  63
  64 /**
  65  * Accept server file descriptor.
  66  */
  67 static int g_acceptServerFD = -1;
  68
  69 /**
  70  * Mutex to synchronize device object list.
  71  */
  72 static ca_mutex g_mutexObjectList = NULL;
  73
  74 /**
  75  * Conditional mutex to synchronize.
  76  */
  77 static ca_cond g_condObjectList = NULL;
  78
  79 /**
  80  * Maintains the callback to be notified when data received from remote device.
  81  */
  82 static CATCPPacketReceivedCallback g_packetReceivedCallback;
  83
  84 /**
  85  * Error callback to update error in TCP.
  86  */
  87 static CATCPErrorHandleCallback g_TCPErrorHandler = NULL;
  88
  89 /**
  90  * Connected Callback to pass the connection information to RI.
  91  */
  92 static CATCPKeepAliveHandleCallback g_keepaliveCallback = NULL;
  93
  94 static CAResult_t CATCPCreateMutex();
  95 static void CATCPDestroyMutex();
  96 static CAResult_t CATCPCreateCond();
  97 static void CATCPDestroyCond();
  98 static CAResult_t CACreateAcceptSocket();
  99 static void CAAcceptConnection();
 100 static void CAFindReadyMessage();
 101 static void CASelectReturned(fd_set *readFds, int ret);
 102 static void CAReceiveMessage(int fd);
 103 static void CAReceiveHandler(void *data);
 104 static int CATCPCreateSocket(int family, CATCPSessionInfo_t *tcpServerInfo);
 105
 106 #define CHECKFD(FD) \
 107     if (FD > caglobals.tcp.maxfd) \
 108         caglobals.tcp.maxfd = FD;
 109
 110 static void CATCPDestroyMutex()
 111 {
 112     if (g_mutexObjectList)
 113     {
 114         ca_mutex_free(g_mutexObjectList);
 115         g_mutexObjectList = NULL;
 116     }
 117 }
 118
 119 static CAResult_t CATCPCreateMutex()
 120 {
 121     if (!g_mutexObjectList)
 122     {
 123         g_mutexObjectList = ca_mutex_new();
 124         if (!g_mutexObjectList)
 125         {
 126             OIC_LOG(ERROR, TAG, "Failed to created mutex!");
 127             return CA_STATUS_FAILED;
 128         }
 129     }
 130
 131     return CA_STATUS_OK;
 132 }
 133
 134 static void CATCPDestroyCond()
 135 {
 136     if (g_condObjectList)
 137     {
 138         ca_cond_free(g_condObjectList);
 139         g_condObjectList = NULL;
 140     }
 141 }
 142
 143 static CAResult_t CATCPCreateCond()
 144 {
 145     if (!g_condObjectList)
 146     {
 147         g_condObjectList = ca_cond_new();
 148         if (!g_condObjectList)
 149         {
 150             OIC_LOG(ERROR, TAG, "Failed to created cond!");
 151             return CA_STATUS_FAILED;
 152         }
 153     }
 154     return CA_STATUS_OK;
 155 }
 156
 157 static void CAReceiveHandler(void *data)
 158 {
 159     (void)data;
 160     OIC_LOG(DEBUG, TAG, "IN - CAReceiveHandler");
 161
 162     while (!caglobals.tcp.terminate)
 163     {
 164         CAFindReadyMessage();
 165     }
 166
 167     ca_mutex_lock(g_mutexObjectList);
 168     ca_cond_signal(g_condObjectList);
 169     ca_mutex_unlock(g_mutexObjectList);
 170
 171     OIC_LOG(DEBUG, TAG, "OUT - CAReceiveHandler");
 172 }
 173
 174 static void CAFindReadyMessage()
 175 {
 176     fd_set readFds;
 177     struct timeval timeout = { .tv_sec = caglobals.tcp.selectTimeout };
 178
 179     FD_ZERO(&readFds);
 180
 181     if (-1 != g_acceptServerFD)
 182     {
 183         FD_SET(g_acceptServerFD, &readFds);
 184     }
 185     if (-1 != caglobals.tcp.shutdownFds[0])
 186     {
 187         FD_SET(caglobals.tcp.shutdownFds[0], &readFds);
 188     }
 189     if (-1 != caglobals.tcp.connectionFds[0])
 190     {
 191         FD_SET(caglobals.tcp.connectionFds[0], &readFds);
 192     }
 193
 194     uint32_t length = u_arraylist_length(caglobals.tcp.svrlist);
 195     for (size_t i = 0; i < length; i++)
 196     {
 197         CATCPSessionInfo_t *svritem =
 198                 (CATCPSessionInfo_t *) u_arraylist_get(caglobals.tcp.svrlist, i);
 199         if (svritem && 0 <= svritem->fd)
 200         {
 201             FD_SET(svritem->fd, &readFds);
 202         }
 203     }
 204
 205     int ret = select(caglobals.tcp.maxfd + 1, &readFds, NULL, NULL, &timeout);
 206
 207     if (caglobals.tcp.terminate)
 208     {
 209         OIC_LOG_V(DEBUG, TAG, "Packet receiver Stop request received.");
 210         return;
 211     }
 212     if (0 >= ret)
 213     {
 214         if (0 > ret)
 215         {
 216             OIC_LOG_V(FATAL, TAG, "select error %s", strerror(errno));
 217         }
 218         return;
 219     }
 220
 221     CASelectReturned(&readFds, ret);
 222 }
 223
 224 static void CASelectReturned(fd_set *readFds, int ret)
 225 {
 226     (void)ret;
 227
 228     if (g_acceptServerFD != -1 && FD_ISSET(g_acceptServerFD, readFds))
 229     {
 230         CAAcceptConnection();
 231         return;
 232     }
 233     else if (-1 != caglobals.tcp.connectionFds[0] &&
 234             FD_ISSET(caglobals.tcp.connectionFds[0], readFds))
 235     {
 236         // new connection was created from remote device.
 237         // exit the function to update read file descriptor.
 238         char buf[MAX_ADDR_STR_SIZE_CA] = {0};
 239         ssize_t len = read(caglobals.tcp.connectionFds[0], buf, sizeof (buf));
 240         if (-1 == len)
 241         {
 242             return;
 243         }
 244         OIC_LOG_V(DEBUG, TAG, "Received new connection event with [%s]", buf);
 245         FD_CLR(caglobals.tcp.connectionFds[0], readFds);
 246         return;
 247     }
 248     else
 249     {
 250         uint32_t length = u_arraylist_length(caglobals.tcp.svrlist);
 251         for (size_t i = 0; i < length; i++)
 252         {
 253             CATCPSessionInfo_t *svritem =
 254                     (CATCPSessionInfo_t *) u_arraylist_get(caglobals.tcp.svrlist, i);
 255             if (svritem && svritem->fd >= 0)
 256             {
 257                 if (FD_ISSET(svritem->fd, readFds))
 258                 {
 259                     CAReceiveMessage(svritem->fd);
 260                     FD_CLR(svritem->fd, readFds);
 261                 }
 262             }
 263         }
 264     }
 265 }
 266
 267 static void CAAcceptConnection()
 268 {
 269     struct sockaddr_storage clientaddr;
 270     socklen_t clientlen = sizeof (struct sockaddr_in);
 271
 272     int sockfd = accept(g_acceptServerFD, (struct sockaddr *)&clientaddr,
 273                         &clientlen);
 274     if (-1 != sockfd)
 275     {
 276         CATCPSessionInfo_t *svritem =
 277                 (CATCPSessionInfo_t *) OICCalloc(1, sizeof (*svritem));
 278         if (!svritem)
 279         {
 280             OIC_LOG(ERROR, TAG, "Out of memory");
 281             close(sockfd);
 282             return;
 283         }
 284
 285         svritem->fd = sockfd;
 286         CAConvertAddrToName((struct sockaddr_storage *)&clientaddr, clientlen,
 287                             (char *) &svritem->sep.endpoint.addr, &svritem->sep.endpoint.port);
 288
 289         ca_mutex_lock(g_mutexObjectList);
 290         bool result = u_arraylist_add(caglobals.tcp.svrlist, svritem);
 291         if (!result)
 292         {
 293             OIC_LOG(ERROR, TAG, "u_arraylist_add failed.");
 294             close(sockfd);
 295             OICFree(svritem);
 296             ca_mutex_unlock(g_mutexObjectList);
 297             return;
 298         }
 299         ca_mutex_unlock(g_mutexObjectList);
 300
 301         CHECKFD(sockfd);
 302     }
 303 }
 304
 305 static void CAReceiveMessage(int fd)
 306 {
 307     // #1. get remote device information from file descriptor.
 308     size_t index = 0;
 309     CATCPSessionInfo_t *svritem = CAGetSessionInfoFromFD(fd, &index);
 310     if (!svritem)
 311     {
 312         OIC_LOG(ERROR, TAG, "there is no connection information in list");
 313         return;
 314     }
 315
 316     // #2. get already allocated memory size.
 317     size_t bufSize = (svritem->totalDataLen == 0) ? TCP_MAX_HEADER_LEN : svritem->totalDataLen;
 318     if (!svritem->recvData)
 319     {
 320         svritem->recvData = (unsigned char *) OICCalloc(1, bufSize);
 321         if (!svritem->recvData)
 322         {
 323             OIC_LOG(ERROR, TAG, "out of memory");
 324             CADisconnectTCPSession(svritem, index);
 325             return;
 326         }
 327     }
 328
 329     // #3. receive data from remote device.
 330     ssize_t recvLen = recv(fd, svritem->recvData + svritem->recvDataLen,
 331                            bufSize - svritem->recvDataLen, 0);
 332     if (recvLen <= 0)
 333     {
 334         if(EWOULDBLOCK != errno)
 335         {
 336             OIC_LOG_V(ERROR, TAG, "Recvfrom failed %s", strerror(errno));
 337             CADisconnectTCPSession(svritem, index);
 338         }
 339         return;
 340     }
 341     svritem->recvDataLen += recvLen;
 342
 343     // #4. get actual data length from coap over tcp header.
 344     if (!svritem->totalDataLen)
 345     {
 346         coap_transport_type transport = coap_get_tcp_header_type_from_initbyte(
 347                 ((unsigned char *) svritem->recvData)[0] >> 4);
 348
 349         size_t headerLen = coap_get_tcp_header_length_for_transport(transport);
 350         if (svritem->recvDataLen >= headerLen)
 351         {
 352             svritem->totalDataLen = CAGetTotalLengthFromHeader(
 353                     (unsigned char *) svritem->recvData);
 354             bufSize = svritem->totalDataLen;
 355             unsigned char *newBuf = OICRealloc(svritem->recvData, bufSize);
 356             if (!newBuf)
 357             {
 358                 OIC_LOG(ERROR, TAG, "out of memory");
 359                 CADisconnectTCPSession(svritem, index);
 360                 return;
 361             }
 362             svritem->recvData = newBuf;
 363         }
 364     }
 365
 366     // #5. pass the received data information to upper layer.
 367     if ((svritem->totalDataLen == svritem->recvDataLen) && g_packetReceivedCallback)
 368     {
 369         svritem->sep.endpoint.adapter = CA_ADAPTER_TCP;
 370         g_packetReceivedCallback(&svritem->sep, svritem->recvData, svritem->recvDataLen);
 371         OIC_LOG_V(DEBUG, TAG, "total received data len:%d", svritem->recvDataLen);
 372
 373         // initialize data info to receive next message.
 374         OICFree(svritem->recvData);
 375         svritem->recvData = NULL;
 376         svritem->recvDataLen = 0;
 377         svritem->totalDataLen = 0;
 378     }
 379
 380     return;
 381 }
 382
 383 static void CAWakeUpForReadFdsUpdate(const char *host)
 384 {
 385     if (caglobals.tcp.connectionFds[1] != -1)
 386     {
 387         ssize_t len = 0;
 388         do
 389         {
 390             len = write(caglobals.tcp.connectionFds[1], host, strlen(host));
 391         } while ((len == -1) && (errno == EINTR));
 392
 393         if ((len == -1) && (errno != EINTR) && (errno != EPIPE))
 394         {
 395             OIC_LOG_V(DEBUG, TAG, "write failed: %s", strerror(errno));
 396         }
 397     }
 398 }
 399
 400 static int CATCPCreateSocket(int family, CATCPSessionInfo_t *svritem)
 401 {
 402     // create tcp socket
 403     int fd = socket(family, SOCK_STREAM, IPPROTO_TCP);
 404     if (-1 == fd)
 405     {
 406         OIC_LOG_V(ERROR, TAG, "create socket failed: %s", strerror(errno));
 407         goto exit;
 408     }
 409
 410     struct sockaddr_storage sa = { .ss_family = family };
 411     CAConvertNameToAddr(svritem->sep.endpoint.addr, svritem->sep.endpoint.port, &sa);
 412     socklen_t socklen = sizeof (struct sockaddr_in);
 413
 414     // connect to TCP server
 415     int ret = connect(fd, (struct sockaddr *)&sa, socklen);
 416     if (0 == ret)
 417     {
 418         OIC_LOG(DEBUG, TAG, "connect socket success");
 419         CAWakeUpForReadFdsUpdate(svritem->sep.endpoint.addr);
 420     }
 421     else
 422     {
 423         OIC_LOG(ERROR, TAG, "failed to connect socket");
 424         goto exit;
 425     }
 426
 427     return fd;
 428
 429 exit:
 430     if (fd >= 0)
 431     {
 432         close(fd);
 433     }
 434     return -1;
 435 }
 436
 437 static CAResult_t CACreateAcceptSocket()
 438 {
 439     int reuse = 1;
 440     struct sockaddr_in server = { .sin_addr.s_addr = INADDR_ANY,
 441                                   .sin_family = AF_INET,
 442                                   .sin_port = htons(SERVER_PORT),
 443                                   .sin_zero = { 0 } };
 444
 445     g_acceptServerFD = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
 446     if (g_acceptServerFD < 0)
 447     {
 448         OIC_LOG(ERROR, TAG, "Failed to create socket");
 449         goto exit;
 450     }
 451
 452     if (-1 == setsockopt(g_acceptServerFD, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse)))
 453     {
 454         OIC_LOG(ERROR, TAG, "setsockopt SO_REUSEADDR");
 455         goto exit;
 456     }
 457
 458     int serverlen = sizeof(server);
 459     if (-1 == bind(g_acceptServerFD, (struct sockaddr *)&server, serverlen))
 460     {
 461         OIC_LOG(ERROR, TAG, "bind() error");
 462         goto exit;
 463     }
 464
 465     if (listen(g_acceptServerFD, caglobals.tcp.listenBacklog) != 0)
 466     {
 467         OIC_LOG(ERROR, TAG, "listen() error");
 468         goto exit;
 469     }
 470
 471     CHECKFD(g_acceptServerFD);
 472
 473     return CA_STATUS_OK;
 474
 475 exit:
 476     if (g_acceptServerFD >= 0)
 477     {
 478         close(g_acceptServerFD);
 479         g_acceptServerFD = -1;
 480     }
 481     return CA_STATUS_FAILED;
 482 }
 483
 484 static void CAInitializePipe(int *fds)
 485 {
 486     int ret = pipe(fds);
 487     if (-1 != ret)
 488     {
 489         ret = fcntl(fds[0], F_GETFD);
 490         if (-1 != ret)
 491         {
 492             ret = fcntl(fds[0], F_SETFD, ret|FD_CLOEXEC);
 493         }
 494         if (-1 != ret)
 495         {
 496             ret = fcntl(fds[1], F_GETFD);
 497         }
 498         if (-1 != ret)
 499         {
 500             ret = fcntl(fds[1], F_SETFD, ret|FD_CLOEXEC);
 501         }
 502         if (-1 == ret)
 503         {
 504             close(fds[1]);
 505             close(fds[0]);
 506
 507             fds[0] = -1;
 508             fds[1] = -1;
 509
 510             OIC_LOG_V(ERROR, TAG, "pipe failed: %s", strerror(errno));
 511         }
 512     }
 513 }
 514
 515 CAResult_t CATCPStartServer(const ca_thread_pool_t threadPool)
 516 {
 517     if (caglobals.tcp.started)
 518     {
 519         return CA_STATUS_OK;
 520     }
 521
 522     if (!caglobals.tcp.ipv4tcpenabled)
 523     {
 524         caglobals.tcp.ipv4tcpenabled = true;    // only needed to run CA tests
 525     }
 526
 527     CAResult_t res = CATCPCreateMutex();
 528     if (CA_STATUS_OK == res)
 529     {
 530         res = CATCPCreateCond();
 531     }
 532     if (CA_STATUS_OK != res)
 533     {
 534         OIC_LOG(ERROR, TAG, "failed to create mutex/cond");
 535         return res;
 536     }
 537
 538     ca_mutex_lock(g_mutexObjectList);
 539     if (!caglobals.tcp.svrlist)
 540     {
 541         caglobals.tcp.svrlist = u_arraylist_create();
 542     }
 543     ca_mutex_unlock(g_mutexObjectList);
 544
 545     res = CACreateAcceptSocket();
 546     if (CA_STATUS_OK != res)
 547     {
 548         OIC_LOG(ERROR, TAG, "failed to create accept socket");
 549         return res;
 550     }
 551
 552     // create pipe for fast shutdown
 553     CAInitializePipe(caglobals.tcp.shutdownFds);
 554     CHECKFD(caglobals.tcp.shutdownFds[0]);
 555     CHECKFD(caglobals.tcp.shutdownFds[1]);
 556
 557     // create pipe for connection event
 558     CAInitializePipe(caglobals.tcp.connectionFds);
 559     CHECKFD(caglobals.tcp.connectionFds[0]);
 560     CHECKFD(caglobals.tcp.connectionFds[1]);
 561
 562     caglobals.tcp.terminate = false;
 563     res = ca_thread_pool_add_task(threadPool, CAReceiveHandler, NULL);
 564     if (CA_STATUS_OK != res)
 565     {
 566         OIC_LOG(ERROR, TAG, "thread_pool_add_task failed");
 567         return res;
 568     }
 569     OIC_LOG(DEBUG, TAG, "CAReceiveHandler thread started successfully.");
 570
 571     caglobals.tcp.started = true;
 572     return CA_STATUS_OK;
 573 }
 574
 575 void CATCPStopServer()
 576 {
 577     // mutex lock
 578     ca_mutex_lock(g_mutexObjectList);
 579
 580     // set terminate flag
 581     caglobals.tcp.terminate = true;
 582
 583     if (caglobals.tcp.shutdownFds[1] != -1)
 584     {
 585         close(caglobals.tcp.shutdownFds[1]);
 586         // receive thread will stop immediately
 587     }
 588
 589     if (caglobals.tcp.connectionFds[1] != -1)
 590     {
 591         close(caglobals.tcp.connectionFds[1]);
 592     }
 593
 594     if (caglobals.tcp.started)
 595     {
 596         ca_cond_wait(g_condObjectList, g_mutexObjectList);
 597     }
 598     caglobals.tcp.started = false;
 599
 600     // mutex unlock
 601     ca_mutex_unlock(g_mutexObjectList);
 602
 603     if (-1 != g_acceptServerFD)
 604     {
 605         close(g_acceptServerFD);
 606         g_acceptServerFD = -1;
 607     }
 608
 609     CATCPDisconnectAll();
 610     CATCPDestroyMutex();
 611     CATCPDestroyCond();
 612 }
 613
 614 void CATCPSetPacketReceiveCallback(CATCPPacketReceivedCallback callback)
 615 {
 616     g_packetReceivedCallback = callback;
 617 }
 618
 619 void CATCPSetKeepAliveCallback(CATCPKeepAliveHandleCallback keepaliveHandler)
 620 {
 621     g_keepaliveCallback = keepaliveHandler;
 622 }
 623
 624 static size_t CACheckPayloadLength(const void *data, size_t dlen)
 625 {
 626     VERIFY_NON_NULL_RET(data, TAG, "data", -1);
 627
 628     coap_transport_type transport = coap_get_tcp_header_type_from_initbyte(
 629             ((unsigned char *)data)[0] >> 4);
 630
 631     coap_pdu_t *pdu = coap_new_pdu(transport, dlen);
 632     if (!pdu)
 633     {
 634         OIC_LOG(ERROR, TAG, "outpdu is null");
 635         return 0;
 636     }
 637
 638     int ret = coap_pdu_parse((unsigned char *) data, dlen, pdu, transport);
 639     if (0 >= ret)
 640     {
 641         OIC_LOG(ERROR, TAG, "pdu parse failed");
 642         coap_delete_pdu(pdu);
 643         return 0;
 644     }
 645
 646     size_t payloadLen = 0;
 647     size_t headerSize = coap_get_tcp_header_length_for_transport(transport);
 648     OIC_LOG_V(DEBUG, TAG, "headerSize : %d, pdu length : %d",
 649               headerSize, pdu->length);
 650     if (pdu->length > headerSize)
 651     {
 652         payloadLen = (unsigned char *) pdu->hdr + pdu->length - pdu->data;
 653     }
 654
 655     OICFree(pdu);
 656
 657     return payloadLen;
 658 }
 659
 660 static void sendData(const CAEndpoint_t *endpoint,
 661                      const void *data, size_t dlen)
 662 {
 663     // #1. get TCP Server object from list
 664     size_t index = 0;
 665     CATCPSessionInfo_t *svritem = CAGetTCPSessionInfoFromEndpoint(endpoint, &index);
 666     if (!svritem)
 667     {
 668         // if there is no connection info, connect to TCP Server
 669         svritem = CAConnectTCPSession(endpoint);
 670         if (!svritem)
 671         {
 672             OIC_LOG(ERROR, TAG, "Failed to create TCP server object");
 673             g_TCPErrorHandler(endpoint, data, dlen, CA_SEND_FAILED);
 674             return;
 675         }
 676     }
 677
 678     // #2. check payload length
 679     size_t payloadLen = CACheckPayloadLength(data, dlen);
 680     // if payload length is zero, disconnect from TCP server
 681     if (!payloadLen)
 682     {
 683         OIC_LOG(DEBUG, TAG, "payload length is zero, disconnect from remote device");
 684         CADisconnectTCPSession(svritem, index);
 685         return;
 686     }
 687
 688     // #3. check connection state
 689     if (svritem->fd < 0)
 690     {
 691         // if file descriptor value is wrong, remove TCP Server info from list
 692         OIC_LOG(ERROR, TAG, "Failed to connect to TCP server");
 693         CADisconnectTCPSession(svritem, index);
 694         g_TCPErrorHandler(endpoint, data, dlen, CA_SEND_FAILED);
 695         return;
 696     }
 697
 698     // #4. send data to TCP Server
 699     ssize_t remainLen = dlen;
 700     do
 701     {
 702         ssize_t len = send(svritem->fd, data, remainLen, 0);
 703         if (-1 == len)
 704         {
 705             if (EWOULDBLOCK != errno)
 706             {
 707                 OIC_LOG_V(ERROR, TAG, "unicast ipv4tcp sendTo failed: %s", strerror(errno));
 708                 g_TCPErrorHandler(endpoint, data, dlen, CA_SEND_FAILED);
 709                 return;
 710             }
 711             continue;
 712         }
 713         data += len;
 714         remainLen -= len;
 715     } while (remainLen > 0);
 716
 717     OIC_LOG_V(INFO, TAG, "unicast ipv4tcp sendTo is successful: %zu bytes", dlen);
 718 }
 719
 720 void CATCPSendData(CAEndpoint_t *endpoint, const void *data, uint32_t datalen,
 721                    bool isMulticast)
 722 {
 723     VERIFY_NON_NULL_VOID(endpoint, TAG, "endpoint is NULL");
 724     VERIFY_NON_NULL_VOID(data, TAG, "data is NULL");
 725
 726     if (!isMulticast)
 727     {
 728         if (caglobals.tcp.ipv4tcpenabled && (endpoint->adapter & CA_ADAPTER_TCP))
 729         {
 730             sendData(endpoint, data, datalen);
 731         }
 732     }
 733 }
 734
 735 CAResult_t CAGetTCPInterfaceInformation(CAEndpoint_t **info, uint32_t *size)
 736 {
 737     VERIFY_NON_NULL(info, TAG, "info is NULL");
 738     VERIFY_NON_NULL(size, TAG, "size is NULL");
 739
 740     return CA_NOT_SUPPORTED;
 741 }
 742
 743 CATCPSessionInfo_t *CAConnectTCPSession(const CAEndpoint_t *endpoint)
 744 {
 745     VERIFY_NON_NULL_RET(endpoint, TAG, "endpoint is NULL", NULL);
 746
 747     // #1. create TCP server object
 748     CATCPSessionInfo_t *svritem = (CATCPSessionInfo_t *) OICCalloc(1, sizeof (*svritem));
 749     if (!svritem)
 750     {
 751         OIC_LOG(ERROR, TAG, "Out of memory");
 752         return NULL;
 753     }
 754     memcpy(svritem->sep.endpoint.addr, endpoint->addr, sizeof(svritem->sep.endpoint.addr));
 755     svritem->sep.endpoint.port = endpoint->port;
 756
 757     // #2. create the socket and connect to TCP server
 758     if (caglobals.tcp.ipv4tcpenabled)
 759     {
 760         int fd = CATCPCreateSocket(AF_INET, svritem);
 761         if (-1 == fd)
 762         {
 763             OICFree(svritem);
 764             return NULL;
 765         }
 766
 767         // #3. add TCP connection info to list
 768         svritem->fd = fd;
 769         ca_mutex_lock(g_mutexObjectList);
 770         if (caglobals.tcp.svrlist)
 771         {
 772             bool res = u_arraylist_add(caglobals.tcp.svrlist, svritem);
 773             if (!res)
 774             {
 775                 OIC_LOG(ERROR, TAG, "u_arraylist_add failed.");
 776                 close(svritem->fd);
 777                 OICFree(svritem);
 778                 ca_mutex_unlock(g_mutexObjectList);
 779                 return NULL;
 780             }
 781         }
 782         ca_mutex_unlock(g_mutexObjectList);
 783
 784         CHECKFD(fd);
 785
 786         // pass the connection information to RI for keepalive.
 787         if (g_keepaliveCallback)
 788         {
 789             g_keepaliveCallback(svritem->sep.endpoint.addr, svritem->sep.endpoint.port, true);
 790         }
 791     }
 792
 793     return svritem;
 794 }
 795
 796 CAResult_t CADisconnectTCPSession(CATCPSessionInfo_t *svritem, size_t index)
 797 {
 798     VERIFY_NON_NULL(svritem, TAG, "svritem is NULL");
 799
 800     ca_mutex_lock(g_mutexObjectList);
 801
 802     // close the socket and remove TCP connection info in list
 803     if (svritem->fd >= 0)
 804     {
 805         close(svritem->fd);
 806     }
 807     u_arraylist_remove(caglobals.tcp.svrlist, index);
 808     OICFree(svritem->recvData);
 809     OICFree(svritem);
 810     ca_mutex_unlock(g_mutexObjectList);
 811
 812     // pass the connection information to RI for keepalive.
 813     if (g_keepaliveCallback)
 814     {
 815         g_keepaliveCallback(svritem->sep.endpoint.addr, svritem->sep.endpoint.port, false);
 816     }
 817
 818     return CA_STATUS_OK;
 819 }
 820
 821 void CATCPDisconnectAll()
 822 {
 823     ca_mutex_lock(g_mutexObjectList);
 824     uint32_t length = u_arraylist_length(caglobals.tcp.svrlist);
 825
 826     CATCPSessionInfo_t *svritem = NULL;
 827     for (size_t i = 0; i < length; i++)
 828     {
 829         svritem = (CATCPSessionInfo_t *) u_arraylist_get(caglobals.tcp.svrlist, i);
 830         if (svritem && svritem->fd >= 0)
 831         {
 832             shutdown(svritem->fd, SHUT_RDWR);
 833             close(svritem->fd);
 834             OICFree(svritem->recvData);
 835         }
 836     }
 837     u_arraylist_destroy(caglobals.tcp.svrlist);
 838     ca_mutex_unlock(g_mutexObjectList);
 839 }
 840
 841 CATCPSessionInfo_t *CAGetTCPSessionInfoFromEndpoint(const CAEndpoint_t *endpoint,
 842                                                     size_t *index)
 843 {
 844     VERIFY_NON_NULL_RET(endpoint, TAG, "endpoint is NULL", NULL);
 845     VERIFY_NON_NULL_RET(index, TAG, "index is NULL", NULL);
 846
 847     // get connection info from list
 848     uint32_t length = u_arraylist_length(caglobals.tcp.svrlist);
 849     for (size_t i = 0; i < length; i++)
 850     {
 851         CATCPSessionInfo_t *svritem = (CATCPSessionInfo_t *) u_arraylist_get(
 852                 caglobals.tcp.svrlist, i);
 853         if (!svritem)
 854         {
 855             continue;
 856         }
 857
 858         if (!strncmp(svritem->sep.endpoint.addr, endpoint->addr,
 859                      sizeof(svritem->sep.endpoint.addr))
 860                 && (svritem->sep.endpoint.port == endpoint->port))
 861         {
 862             *index = i;
 863             return svritem;
 864         }
 865     }
 866
 867     return NULL;
 868 }
 869
 870 CATCPSessionInfo_t *CAGetSessionInfoFromFD(int fd, size_t *index)
 871 {
 872     ca_mutex_lock(g_mutexObjectList);
 873
 874     // check from the last item.
 875     CATCPSessionInfo_t *svritem = NULL;
 876     uint32_t length = u_arraylist_length(caglobals.tcp.svrlist);
 877     for (size_t i = 0; i < length; i++)
 878     {
 879         svritem = (CATCPSessionInfo_t *) u_arraylist_get(caglobals.tcp.svrlist, i);
 880
 881         if (svritem && svritem->fd == fd)
 882         {
 883             *index = i;
 884             ca_mutex_unlock(g_mutexObjectList);
 885             return svritem;
 886         }
 887     }
 888
 889     ca_mutex_unlock(g_mutexObjectList);
 890
 891     return NULL;
 892 }
 893
 894 size_t CAGetTotalLengthFromHeader(const unsigned char *recvBuffer)
 895 {
 896     OIC_LOG(DEBUG, TAG, "IN - CAGetTotalLengthFromHeader");
 897
 898     coap_transport_type transport = coap_get_tcp_header_type_from_initbyte(
 899             ((unsigned char *)recvBuffer)[0] >> 4);
 900     size_t optPaylaodLen = coap_get_length_from_header((unsigned char *)recvBuffer,
 901                                                         transport);
 902     size_t headerLen = coap_get_tcp_header_length((unsigned char *)recvBuffer);
 903
 904     OIC_LOG_V(DEBUG, TAG, "option/paylaod length [%d]", optPaylaodLen);
 905     OIC_LOG_V(DEBUG, TAG, "header length [%d]", headerLen);
 906     OIC_LOG_V(DEBUG, TAG, "total data length [%d]", headerLen + optPaylaodLen);
 907
 908     OIC_LOG(DEBUG, TAG, "OUT - CAGetTotalLengthFromHeader");
 909     return headerLen + optPaylaodLen;
 910 }
 911
 912 void CATCPSetErrorHandler(CATCPErrorHandleCallback errorHandleCallback)
 913 {
 914     g_TCPErrorHandler = errorHandleCallback;
 915 }