diff --git a/src/wtp/wtp_dfa.c b/src/wtp/wtp_dfa.c index 5b4f727..4a98bb0 100644 --- a/src/wtp/wtp_dfa.c +++ b/src/wtp/wtp_dfa.c @@ -301,25 +301,166 @@ static void wtp_dfa_closeapp(void) { ASSERT(g_wtp.state == CAPWAP_DEAD_STATE); } +static void wtp_dfa_process_packet(void *buffer, int buffersize, + union sockaddr_capwap *fromaddr, + union sockaddr_capwap *toaddr) +{ + int check, res; + char plain[CAPWAP_MAX_PACKET_SIZE]; + struct capwap_packet_rxmng* rxmngpacket; + struct capwap_parsed_packet packet; + + /* Check source */ + if (g_wtp.state != CAPWAP_DISCOVERY_STATE && + capwap_compare_ip(&g_wtp.dtls.peeraddr, fromaddr)) { + capwap_logging_debug("CAPWAP packet from unknown WTP when not in DISCOVERY, drop packet"); + return; /* Unknown source */ + } + + /* Check of packet */ + check = capwap_sanity_check(g_wtp.state, buffer, buffersize, g_wtp.dtls.enable); + switch (check) { + case CAPWAP_PLAIN_PACKET: + break; + + case CAPWAP_DTLS_PACKET: { + int oldaction = g_wtp.dtls.action; + + /* Decrypt packet */ + buffersize = capwap_decrypt_packet(&g_wtp.dtls, buffer, buffersize, plain, CAPWAP_MAX_PACKET_SIZE); + if (buffersize > 0) { + buffer = plain; + break; + } + + if (buffersize == CAPWAP_ERROR_AGAIN) { + /* Check is handshake complete */ + if (oldaction == CAPWAP_DTLS_ACTION_HANDSHAKE && + g_wtp.dtls.action == CAPWAP_DTLS_ACTION_DATA) { + if (g_wtp.state == CAPWAP_DTLS_CONNECT_STATE) { + wtp_send_join(); + } else { + wtp_teardown_connection(); + } + } + } else if (oldaction == CAPWAP_DTLS_ACTION_DATA && + g_wtp.dtls.action == CAPWAP_DTLS_ACTION_SHUTDOWN) { + wtp_teardown_connection(); + } + + return; /* Next packet */ + } + + case CAPWAP_WRONG_PACKET: + capwap_logging_debug("Warning: sanity check failure"); + /* Drop packet */ + return; + + default: + /* TODO: Really? Previosly, this was hidden in the + * overly deep indention, check if that is correct */ + + capwap_logging_debug("Warning: wtp_dfa_running took default fall through"); + return; + } + + /* Defragment management */ + rxmngpacket = wtp_get_packet_rxmng(); + + /* If request, defragmentation packet */ + check = capwap_packet_rxmng_add_recv_packet(rxmngpacket, buffer, buffersize); + if (check == CAPWAP_REQUEST_MORE_FRAGMENT) + return; + if (check != CAPWAP_RECEIVE_COMPLETE_PACKET) { + /* Discard fragments */ + wtp_free_packet_rxmng(); + return; + } + + /* Check for already sent response to packet */ + if (capwap_is_request_type(rxmngpacket->ctrlmsg.type) && + g_wtp.remotetype == rxmngpacket->ctrlmsg.type && + g_wtp.remoteseqnumber == rxmngpacket->ctrlmsg.seq) { + /* Retransmit response */ + if (!capwap_crypt_sendto_fragmentpacket(&g_wtp.dtls, g_wtp.responsefragmentpacket)) { + capwap_logging_error("Error to resend response packet"); + } else { + capwap_logging_debug("Retransmitted control packet"); + } + + /* Discard fragments */ + wtp_free_packet_rxmng(); + return; + } + + /* Check message type */ + res = capwap_check_message_type(rxmngpacket); + if (res != VALID_MESSAGE_TYPE) { + if (res == INVALID_REQUEST_MESSAGE_TYPE) { + capwap_logging_warning("Unexpected Unrecognized Request, send Response Packet with error"); + wtp_send_invalid_request(rxmngpacket, CAPWAP_RESULTCODE_MSG_UNEXPECTED_UNRECOGNIZED_REQUEST); + } + + capwap_logging_debug("Invalid message type"); + wtp_free_packet_rxmng(); + return; + } + + /* Init */ + memset(&packet, 0, sizeof(struct capwap_parsed_packet)); + + /* Parsing packet */ + res = capwap_parsing_packet(rxmngpacket, &packet); + if (res != PARSING_COMPLETE) { + if (res == UNRECOGNIZED_MESSAGE_ELEMENT && + capwap_is_request_type(rxmngpacket->ctrlmsg.type)) { + capwap_logging_warning("Unrecognized Message Element, send Response Packet with error"); + wtp_send_invalid_request(rxmngpacket, CAPWAP_RESULTCODE_FAILURE_UNRECOGNIZED_MESSAGE_ELEMENT); + /* TODO: add the unrecognized message element */ + } + + /* */ + capwap_logging_debug("Failed parsing packet"); + capwap_free_parsed_packet(&packet); + wtp_free_packet_rxmng(); + return; + } + + /* Validate packet */ + if (capwap_validate_parsed_packet(&packet, NULL)) { + if (capwap_is_request_type(rxmngpacket->ctrlmsg.type)) { + capwap_logging_warning("Missing Mandatory Message Element, send Response Packet with error"); + wtp_send_invalid_request(rxmngpacket, CAPWAP_RESULTCODE_FAILURE_MISSING_MANDATORY_MSG_ELEMENT); + } + + /* */ + capwap_logging_debug("Failed validation parsed packet"); + capwap_free_parsed_packet(&packet); + wtp_free_packet_rxmng(); + return; + } + + /* Receive a complete packet */ + wtp_dfa_execute(&packet); + + /* Free packet */ + capwap_free_parsed_packet(&packet); + + wtp_free_packet_rxmng(); +} + /* WTP state machine */ -int wtp_dfa_running(void) { - int res; +int wtp_dfa_running(void) +{ int result = CAPWAP_SUCCESSFUL; - char bufferencrypt[CAPWAP_MAX_PACKET_SIZE]; - char bufferplain[CAPWAP_MAX_PACKET_SIZE]; - char* buffer; + char buffer[CAPWAP_MAX_PACKET_SIZE]; int buffersize; - struct capwap_parsed_packet packet; - int index; union sockaddr_capwap fromaddr; union sockaddr_capwap toaddr; - /* Init */ - memset(&packet, 0, sizeof(struct capwap_parsed_packet)); - /* Configure poll struct */ if (wtp_dfa_init_fdspool(&g_wtp.fds, &g_wtp.net)) { return CAPWAP_GENERIC_ERROR; @@ -337,13 +478,9 @@ int wtp_dfa_running(void) { /* */ while (g_wtp.state != CAPWAP_DEAD_STATE) { - int check; - struct capwap_packet_rxmng* rxmngpacket; - /* If request wait packet from AC */ - buffer = bufferencrypt; - buffersize = CAPWAP_MAX_PACKET_SIZE; - index = wtp_recvfrom(&g_wtp.fds, buffer, &buffersize, &fromaddr, &toaddr); + buffersize = sizeof(buffer); + index = wtp_recvfrom(&g_wtp.fds, &buffer, &buffersize, &fromaddr, &toaddr); capwap_logging_debug("WTP got data: idx: %d, size: %d", index, buffersize); if (!g_wtp.running) { @@ -370,137 +507,7 @@ int wtp_dfa_running(void) { continue; /* Drop packet */ } - /* Check source */ - if (g_wtp.state != CAPWAP_DISCOVERY_STATE && - capwap_compare_ip(&g_wtp.dtls.peeraddr, &fromaddr)) { - capwap_logging_debug("CAPWAP packet from unknown WTP when not in DISCOVERY, drop packet"); - continue; /* Unknown source */ - } - - /* Check of packet */ - check = capwap_sanity_check(g_wtp.state, buffer, buffersize, g_wtp.dtls.enable); - switch (check) { - case CAPWAP_PLAIN_PACKET: - break; - - case CAPWAP_DTLS_PACKET: { - int oldaction = g_wtp.dtls.action; - - /* Decrypt packet */ - buffersize = capwap_decrypt_packet(&g_wtp.dtls, buffer, buffersize, bufferplain, CAPWAP_MAX_PACKET_SIZE); - if (buffersize > 0) { - buffer = bufferplain; - break; - } - - if (buffersize == CAPWAP_ERROR_AGAIN) { - /* Check is handshake complete */ - if (oldaction == CAPWAP_DTLS_ACTION_HANDSHAKE && - g_wtp.dtls.action == CAPWAP_DTLS_ACTION_DATA) { - if (g_wtp.state == CAPWAP_DTLS_CONNECT_STATE) { - wtp_send_join(); - } else { - wtp_teardown_connection(); - } - } - } else if (oldaction == CAPWAP_DTLS_ACTION_DATA && - g_wtp.dtls.action == CAPWAP_DTLS_ACTION_SHUTDOWN) { - wtp_teardown_connection(); - } - - continue; /* Next packet */ - } - - case CAPWAP_WRONG_PACKET: - capwap_logging_debug("Warning: sanity check failure"); - /* Drop packet */ - continue; - - default: - /* TODO: Really? Previosly, this was hidden in the - * overly deep indention, check if that is correct */ - - capwap_logging_debug("Warning: wtp_dfa_running took default fall through"); - continue; - } - - /* Defragment management */ - rxmngpacket = wtp_get_packet_rxmng(); - - /* If request, defragmentation packet */ - check = capwap_packet_rxmng_add_recv_packet(rxmngpacket, buffer, buffersize); - if (check == CAPWAP_REQUEST_MORE_FRAGMENT) - continue; - if (check != CAPWAP_RECEIVE_COMPLETE_PACKET) { - /* Discard fragments */ - wtp_free_packet_rxmng(); - continue; - } - - /* Check for already response to packet */ - if (capwap_is_request_type(rxmngpacket->ctrlmsg.type) && (g_wtp.remotetype == rxmngpacket->ctrlmsg.type) && (g_wtp.remoteseqnumber == rxmngpacket->ctrlmsg.seq)) { - /* Retransmit response */ - if (!capwap_crypt_sendto_fragmentpacket(&g_wtp.dtls, g_wtp.responsefragmentpacket)) { - capwap_logging_error("Error to resend response packet"); - } else { - capwap_logging_debug("Retrasmitted control packet"); - } - - /* Discard fragments */ - wtp_free_packet_rxmng(); - continue; - } - - /* Check message type */ - res = capwap_check_message_type(rxmngpacket); - if (res != VALID_MESSAGE_TYPE) { - if (res == INVALID_REQUEST_MESSAGE_TYPE) { - capwap_logging_warning("Unexpected Unrecognized Request, send Response Packet with error"); - wtp_send_invalid_request(rxmngpacket, CAPWAP_RESULTCODE_MSG_UNEXPECTED_UNRECOGNIZED_REQUEST); - } - - capwap_logging_debug("Invalid message type"); - wtp_free_packet_rxmng(); - continue; - } - - /* Parsing packet */ - res = capwap_parsing_packet(rxmngpacket, &packet); - if (res != PARSING_COMPLETE) { - if ((res == UNRECOGNIZED_MESSAGE_ELEMENT) && capwap_is_request_type(rxmngpacket->ctrlmsg.type)) { - capwap_logging_warning("Unrecognized Message Element, send Response Packet with error"); - wtp_send_invalid_request(rxmngpacket, CAPWAP_RESULTCODE_FAILURE_UNRECOGNIZED_MESSAGE_ELEMENT); - /* TODO: add the unrecognized message element */ - } - - /* */ - capwap_logging_debug("Failed parsing packet"); - capwap_free_parsed_packet(&packet); - wtp_free_packet_rxmng(); - continue; - } - - /* Validate packet */ - if (capwap_validate_parsed_packet(&packet, NULL)) { - if (capwap_is_request_type(rxmngpacket->ctrlmsg.type)) { - capwap_logging_warning("Missing Mandatory Message Element, send Response Packet with error"); - wtp_send_invalid_request(rxmngpacket, CAPWAP_RESULTCODE_FAILURE_MISSING_MANDATORY_MSG_ELEMENT); - } - - /* */ - capwap_logging_debug("Failed validation parsed packet"); - capwap_free_parsed_packet(&packet); - wtp_free_packet_rxmng(); - continue; - } - - /* Receive a complete packet */ - wtp_dfa_execute(&packet); - - /* Free packet */ - capwap_free_parsed_packet(&packet); - - wtp_free_packet_rxmng(); + wtp_dfa_process_packet(&buffer, buffersize, &fromaddr, &toaddr); } /* Free memory */