// // This file is part of Dire Wolf, an amateur radio packet TNC. // // Copyright (C) 2013, 2014, 2015 John Langner, WB2OSZ // // This program is free software: you can redistribute it and/or modify // it under the terms of the GNU General Public License as published by // the Free Software Foundation, either version 2 of the License, or // (at your option) any later version. // // This program is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // // You should have received a copy of the GNU General Public License // along with this program. If not, see . // /*------------------------------------------------------------------ * * Module: igate.c * * Purpose: IGate client. * * Description: Establish connection with a tier 2 IGate server * and relay packets between RF and Internet. * * References: APRS-IS (Automatic Packet Reporting System-Internet Service) * http://www.aprs-is.net/Default.aspx * * APRS iGate properties * http://wiki.ham.fi/APRS_iGate_properties * *---------------------------------------------------------------*/ /*------------------------------------------------------------------ * * From http://windows.microsoft.com/en-us/windows7/ipv6-frequently-asked-questions * * How can I enable IPv6? * Follow these steps: * * Open Network Connections by clicking the Start button, and then clicking * Control Panel. In the search box, type adapter, and then, under Network * and Sharing Center, click View network connections. * * Right-click your network connection, and then click Properties. * If you're prompted for an administrator password or confirmation, type * the password or provide confirmation. * * Select the check box next to Internet Protocol Version 6 (TCP/IPv6). * *---------------------------------------------------------------*/ /* * Native Windows: Use the Winsock interface. * Linux: Use the BSD socket interface. * Cygwin: Can use either one. */ #if __WIN32__ /* The goal is to support Windows XP and later. */ #include // default is 0x0400 #undef _WIN32_WINNT #define _WIN32_WINNT 0x0501 /* Minimum OS version is XP. */ //#define _WIN32_WINNT 0x0502 /* Minimum OS version is XP with SP2. */ //#define _WIN32_WINNT 0x0600 /* Minimum OS version is Vista. */ #include #else #include #include #include #include #include #include #include #endif #include #include #include #include #include #include "direwolf.h" #include "ax25_pad.h" #include "textcolor.h" #include "version.h" #include "digipeater.h" #include "tq.h" #include "igate.h" #include "latlong.h" #include "pfilter.h" #if __WIN32__ static unsigned __stdcall connnect_thread (void *arg); static unsigned __stdcall igate_recv_thread (void *arg); #else static void * connnect_thread (void *arg); static void * igate_recv_thread (void *arg); #endif static void send_msg_to_server (char *msg); static void xmit_packet (char *message); static void rx_to_ig_init (void); static void rx_to_ig_remember (packet_t pp); static int rx_to_ig_allow (packet_t pp); static void ig_to_tx_init (void); static void ig_to_tx_remember (packet_t pp); static int ig_to_tx_allow (packet_t pp); /* * File descriptor for socket to IGate server. * Set to -1 if not connected. * (Don't use SOCKET type because it is unsigned.) */ static volatile int igate_sock = -1; /* * After connecting to server, we want to make sure * that the login sequence is sent first. * This is set to true after the login is complete. */ static volatile int ok_to_send = 0; /* * Convert Internet address to text. * Can't use InetNtop because it is supported only on Windows Vista and later. */ static char * ia_to_text (int Family, void * pAddr, char * pStringBuf, size_t StringBufSize) { struct sockaddr_in *sa4; struct sockaddr_in6 *sa6; switch (Family) { case AF_INET: sa4 = (struct sockaddr_in *)pAddr; #if __WIN32__ snprintf (pStringBuf, StringBufSize, "%d.%d.%d.%d", sa4->sin_addr.S_un.S_un_b.s_b1, sa4->sin_addr.S_un.S_un_b.s_b2, sa4->sin_addr.S_un.S_un_b.s_b3, sa4->sin_addr.S_un.S_un_b.s_b4); #else inet_ntop (AF_INET, &(sa4->sin_addr), pStringBuf, StringBufSize); #endif break; case AF_INET6: sa6 = (struct sockaddr_in6 *)pAddr; #if __WIN32__ snprintf (pStringBuf, StringBufSize, "%x:%x:%x:%x:%x:%x:%x:%x", ntohs(((unsigned short *)(&(sa6->sin6_addr)))[0]), ntohs(((unsigned short *)(&(sa6->sin6_addr)))[1]), ntohs(((unsigned short *)(&(sa6->sin6_addr)))[2]), ntohs(((unsigned short *)(&(sa6->sin6_addr)))[3]), ntohs(((unsigned short *)(&(sa6->sin6_addr)))[4]), ntohs(((unsigned short *)(&(sa6->sin6_addr)))[5]), ntohs(((unsigned short *)(&(sa6->sin6_addr)))[6]), ntohs(((unsigned short *)(&(sa6->sin6_addr)))[7])); #else inet_ntop (AF_INET6, &(sa6->sin6_addr), pStringBuf, StringBufSize); #endif break; default: snprintf (pStringBuf, StringBufSize, "Invalid address family!"); } //assert (strlen(pStringBuf) < StringBufSize); return pStringBuf; } #if ITEST /* For unit testing. */ int main (int argc, char *argv[]) { struct audio_s audio_config; struct igate_config_s igate_config; struct digi_config_s digi_config; packet_t pp; memset (&audio_config, 0, sizeof(audio_config)); audio_config.adev[0].num_chans = 2; strlcpy (audio_config.achan[0].mycall, "WB2OSZ-1", sizeof(audio_config.achan[0].mycall)); strlcpy (audio_config.achan[1].mycall, "WB2OSZ-2", sizeof(audio_config.achan[0].mycall)); memset (&igate_config, 0, sizeof(igate_config)); strlcpy (igate_config.t2_server_name, "localhost", sizeof(igate_config.t2_server_name)); igate_config.t2_server_port = 14580; strlcpy (igate_config.t2_login, "WB2OSZ-JL", sizeof(igate_config.t2_login)); strlcpy (igate_config.t2_passcode, "-1", sizeof(igate_config.t2_passcode)); igate_config.t2_filter = strdup ("r/1/2/3"); igate_config.tx_chan = 0; strlcpy (igate_config.tx_via, ",WIDE2-1", sizeof(igate_config.tx_via)); igate_config.tx_limit_1 = 3; igate_config.tx_limit_5 = 5; memset (&digi_config, 0, sizeof(digi_config)); igate_init(&igate_config, &digi_config); while (igate_sock == -1) { SLEEP_SEC(1); } SLEEP_SEC (2); pp = ax25_from_text ("A>B,C,D:Ztest message 1", 0); igate_send_rec_packet (0, pp); ax25_delete (pp); SLEEP_SEC (2); pp = ax25_from_text ("A>B,C,D:Ztest message 2", 0); igate_send_rec_packet (0, pp); ax25_delete (pp); SLEEP_SEC (2); pp = ax25_from_text ("A>B,C,D:Ztest message 2", 0); /* Should suppress duplicate. */ igate_send_rec_packet (0, pp); ax25_delete (pp); SLEEP_SEC (2); pp = ax25_from_text ("A>B,TCPIP,D:ZShould drop this due to path", 0); igate_send_rec_packet (0, pp); ax25_delete (pp); SLEEP_SEC (2); pp = ax25_from_text ("A>B,C,D:?Should drop query", 0); igate_send_rec_packet (0, pp); ax25_delete (pp); SLEEP_SEC (5); pp = ax25_from_text ("A>B,C,D:}E>F,G*,H:Zthird party stuff", 0); igate_send_rec_packet (0, pp); ax25_delete (pp); #if 1 while (1) { SLEEP_SEC (20); text_color_set(DW_COLOR_INFO); dw_printf ("Send received packet\n"); send_msg_to_server ("W1ABC>APRS:?\r\n"); } #endif return 0; } #endif /* * Global stuff (to this file) * * These are set by init function and need to * be kept around in case connection is lost and * we need to reestablish the connection later. */ static struct audio_s *save_audio_config_p; static struct igate_config_s *save_igate_config_p; static struct digi_config_s *save_digi_config_p; /* * Statistics. * TODO: need print function. */ static int stats_failed_connect; /* Number of times we tried to connect to */ /* a server and failed. A small number is not */ /* a bad thing. Each name should have a bunch */ /* of addresses for load balancing and */ /* redundancy. */ static int stats_connects; /* Number of successful connects to a server. */ /* Normally you'd expect this to be 1. */ /* Could be larger if one disappears and we */ /* try again to find a different one. */ static time_t stats_connect_at; /* Most recent time connection was established. */ /* can be used to determine elapsed connect time. */ static int stats_rf_recv_packets; /* Number of candidate packets from the radio. */ static int stats_rx_igate_packets; /* Number of packets passed along to the IGate */ /* server after filtering. */ static int stats_uplink_bytes; /* Total number of bytes sent to IGate server */ /* including login, packets, and hearbeats. */ static int stats_downlink_bytes; /* Total number of bytes from IGate server including */ /* packets, heartbeats, other messages. */ static int stats_tx_igate_packets; /* Number of packets from IGate server. */ static int stats_rf_xmit_packets; /* Number of packets passed along to radio */ /* after rate limiting or other restrictions. */ /* We have some statistics. What do we do with them? IGate stations often send packets like this: t2_server_name, p_igate_config->t2_server_port, p_igate_config->t2_login, p_igate_config->t2_passcode, p_igate_config->t2_filter); #endif /* * Save the arguments for later use. */ save_audio_config_p = p_audio_config; save_igate_config_p = p_igate_config; save_digi_config_p = p_digi_config; stats_failed_connect = 0; stats_connects = 0; stats_connect_at = 0; stats_rf_recv_packets = 0; stats_rx_igate_packets = 0; stats_uplink_bytes = 0; stats_downlink_bytes = 0; stats_tx_igate_packets = 0; stats_rf_xmit_packets = 0; rx_to_ig_init (); ig_to_tx_init (); /* * Continue only if we have server name, login, and passcode. */ if (strlen(p_igate_config->t2_server_name) == 0 || strlen(p_igate_config->t2_login) == 0 || strlen(p_igate_config->t2_passcode) == 0) { return; } /* * This connects to the server and sets igate_sock. * It also sends periodic messages to say I'm still alive. */ #if __WIN32__ connnect_th = (HANDLE)_beginthreadex (NULL, 0, connnect_thread, (void *)NULL, 0, NULL); if (connnect_th == NULL) { text_color_set(DW_COLOR_ERROR); dw_printf ("Internal error: Could not create IGate connection thread\n"); return; } #else e = pthread_create (&connect_listen_tid, NULL, connnect_thread, (void *)NULL); if (e != 0) { text_color_set(DW_COLOR_ERROR); perror("Internal error: Could not create IGate connection thread"); return; } #endif /* * This reads messages from client when igate_sock is valid. */ #if __WIN32__ cmd_recv_th = (HANDLE)_beginthreadex (NULL, 0, igate_recv_thread, NULL, 0, NULL); if (cmd_recv_th == NULL) { text_color_set(DW_COLOR_ERROR); dw_printf ("Internal error: Could not create IGate reading thread\n"); return; } #else e = pthread_create (&cmd_listen_tid, NULL, igate_recv_thread, NULL); if (e != 0) { text_color_set(DW_COLOR_ERROR); perror("Internal error: Could not create IGate reading thread"); return; } #endif } /*------------------------------------------------------------------- * * Name: connnect_thread * * Purpose: Establish connection with IGate server. * Send periodic heartbeat to keep keep connection active. * Reconnect if something goes wrong and we got disconnected. * * Inputs: arg - Not used. * * Outputs: igate_sock - File descriptor for communicating with client app. * Will be -1 if not connected. * * References: TCP client example. * http://msdn.microsoft.com/en-us/library/windows/desktop/ms737591(v=vs.85).aspx * * Linux IPv6 HOWTO * http://www.tldp.org/HOWTO/Linux+IPv6-HOWTO/ * *--------------------------------------------------------------------*/ /* * Addresses don't get mixed up very well. * IPv6 always shows up last so we'd probably never * end up using any of them. Use our own shuffle. */ static void shuffle (struct addrinfo *host[], int nhosts) { int j, k; assert (RAND_MAX >= nhosts); /* for % to work right */ if (nhosts < 2) return; srand (time(NULL)); for (j=0; j=0 && kt2_server_port); #if DEBUGx text_color_set(DW_COLOR_DEBUG); dw_printf ("DEBUG: igate connect_thread start, port = %d = '%s'\n", save_igate_config_p->t2_server_port, server_port_str); #endif #if __WIN32__ err = WSAStartup (MAKEWORD(2,2), &wsadata); if (err != 0) { text_color_set(DW_COLOR_ERROR); dw_printf("WSAStartup failed: %d\n", err); return (0); } if (LOBYTE(wsadata.wVersion) != 2 || HIBYTE(wsadata.wVersion) != 2) { text_color_set(DW_COLOR_ERROR); dw_printf("Could not find a usable version of Winsock.dll\n"); WSACleanup(); //sleep (1); return (0); } #endif memset (&hints, 0, sizeof(hints)); hints.ai_family = AF_UNSPEC; /* Allow either IPv4 or IPv6. */ // IPv6 is half baked on Windows XP. // We might need to leave out IPv6 support for Windows version. // hints.ai_family = AF_INET; /* IPv4 only. */ #if IPV6_ONLY /* IPv6 addresses always show up at end of list. */ /* Force use of them for testing. */ hints.ai_family = AF_INET6; /* IPv6 only */ #endif hints.ai_socktype = SOCK_STREAM; hints.ai_protocol = IPPROTO_TCP; /* * Repeat forever. */ while (1) { /* * Connect to IGate server if not currently connected. */ if (igate_sock == -1) { SLEEP_SEC (5); ai_head = NULL; err = getaddrinfo(save_igate_config_p->t2_server_name, server_port_str, &hints, &ai_head); if (err != 0) { text_color_set(DW_COLOR_ERROR); #if __WIN32__ dw_printf ("Can't get address for IGate server %s, err=%d\n", save_igate_config_p->t2_server_name, WSAGetLastError()); #else dw_printf ("Can't get address for IGate server %s, %s\n", save_igate_config_p->t2_server_name, gai_strerror(err)); #endif freeaddrinfo(ai_head); continue; } #if DEBUG_DNS text_color_set(DW_COLOR_DEBUG); dw_printf ("getaddrinfo returns:\n"); #endif num_hosts = 0; for (ai = ai_head; ai != NULL; ai = ai->ai_next) { #if DEBUG_DNS text_color_set(DW_COLOR_DEBUG); ia_to_text (ai->ai_family, ai->ai_addr, ipaddr_str, sizeof(ipaddr_str)); dw_printf (" %s\n", ipaddr_str); #endif hosts[num_hosts] = ai; if (num_hosts < MAX_HOSTS) num_hosts++; } // We can get multiple addresses back for the host name. // These should be somewhat randomized for load balancing. // It turns out the IPv6 addresses are always at the // end for both Windows and Linux. We do our own shuffling // to mix them up better and give IPv6 a chance. shuffle (hosts, num_hosts); #if DEBUG_DNS text_color_set(DW_COLOR_DEBUG); dw_printf ("after shuffling:\n"); for (n=0; nai_family, hosts[n]->ai_addr, ipaddr_str, sizeof(ipaddr_str)); dw_printf (" %s\n", ipaddr_str); } #endif // Try each address until we find one that is successful. for (n=0; nai_family, ai->ai_addr, ipaddr_str, sizeof(ipaddr_str)); is = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); #if __WIN32__ if (is == INVALID_SOCKET) { text_color_set(DW_COLOR_ERROR); dw_printf ("IGate: Socket creation failed, err=%d", WSAGetLastError()); WSACleanup(); is = -1; stats_failed_connect++; continue; } #else if (err != 0) { text_color_set(DW_COLOR_INFO); dw_printf("Connect to IGate server %s (%s) failed.\n\n", save_igate_config_p->t2_server_name, ipaddr_str); (void) close (is); is = -1; stats_failed_connect++; continue; } #endif #ifndef DEBUG_DNS err = connect(is, ai->ai_addr, (int)ai->ai_addrlen); #if __WIN32__ if (err == SOCKET_ERROR) { text_color_set(DW_COLOR_INFO); dw_printf("Connect to IGate server %s (%s) failed.\n\n", save_igate_config_p->t2_server_name, ipaddr_str); closesocket (is); is = -1; stats_failed_connect++; continue; } // TODO: set TCP_NODELAY? #else if (err != 0) { text_color_set(DW_COLOR_INFO); dw_printf("Connect to IGate server %s (%s) failed.\n\n", save_igate_config_p->t2_server_name, ipaddr_str); (void) close (is); is = -1; stats_failed_connect++; continue; } /* IGate documentation says to use it. */ /* Does it really make a difference for this application? */ int flag = 1; err = setsockopt (is, IPPROTO_TCP, TCP_NODELAY, (void*)(long)(&flag), sizeof(flag)); if (err < 0) { text_color_set(DW_COLOR_INFO); dw_printf("setsockopt TCP_NODELAY failed.\n"); } #endif stats_connects++; stats_connect_at = time(NULL); /* Success. */ text_color_set(DW_COLOR_INFO); dw_printf("\nNow connected to IGate server %s (%s)\n", save_igate_config_p->t2_server_name, ipaddr_str ); if (strchr(ipaddr_str, ':') != NULL) { dw_printf("Check server status here http://[%s]:14501\n\n", ipaddr_str); } else { dw_printf("Check server status here http://%s:14501\n\n", ipaddr_str); } /* * Set igate_sock so everyone else can start using it. * But make the Rx -> Internet messages wait until after login. */ ok_to_send = 0; igate_sock = is; #endif break; } freeaddrinfo(ai_head); if (igate_sock != -1) { char stemp[256]; /* * Send login message. * Software name and version must not contain spaces. */ SLEEP_SEC(3); snprintf (stemp, sizeof(stemp), "user %s pass %s vers Dire-Wolf %d.%d", save_igate_config_p->t2_login, save_igate_config_p->t2_passcode, MAJOR_VERSION, MINOR_VERSION); if (save_igate_config_p->t2_filter != NULL) { strlcat (stemp, " filter ", sizeof(stemp)); strlcat (stemp, save_igate_config_p->t2_filter, sizeof(stemp)); } strlcat (stemp, "\r\n", sizeof(stemp)); send_msg_to_server (stemp); /* Delay until it is ok to start sending packets. */ SLEEP_SEC(7); ok_to_send = 1; } } /* * If connected to IGate server, send heartbeat periodically to keep connection active. */ if (igate_sock != -1) { SLEEP_SEC(10); } if (igate_sock != -1) { SLEEP_SEC(10); } if (igate_sock != -1) { SLEEP_SEC(10); } if (igate_sock != -1) { char heartbeat[10]; strlcpy (heartbeat, "#\r\n", sizeof(heartbeat)); /* This will close the socket if any error. */ send_msg_to_server (heartbeat); } } } /* end connnect_thread */ /*------------------------------------------------------------------- * * Name: igate_send_rec_packet * * Purpose: Send a packet to the IGate server * * Inputs: chan - Radio channel it was received on. * * recv_pp - Pointer to packet object. * *** CALLER IS RESPONSIBLE FOR DELETING IT! ** * * * Description: Send message to IGate Server if connected. * * Assumptions: (1) Caller has already verified it is an APRS packet. * i.e. control = 3 for UI frame, protocol id = 0xf0 for no layer 3 * * (2) This is being called only for packets received with * a correct CRC. We don't want to propagate corrupted data. * *--------------------------------------------------------------------*/ void igate_send_rec_packet (int chan, packet_t recv_pp) { packet_t pp; int n; unsigned char *pinfo; char *p; char msg[520]; /* Message to IGate max 512 characters. */ int info_len; if (igate_sock == -1) { return; /* Silently discard if not connected. */ } if ( ! ok_to_send) { return; /* Login not complete. */ } /* * Check for filtering from specified channel to the IGate server. */ if (save_digi_config_p->filter_str[chan][MAX_CHANS] != NULL) { if (pfilter(chan, MAX_CHANS, save_digi_config_p->filter_str[chan][MAX_CHANS], recv_pp) != 1) { // TODO1.2: take out debug message. //#if DEBUG text_color_set(DW_COLOR_DEBUG); dw_printf ("Packet from channel %d to IGate was rejected by filter: %s\n", chan, save_digi_config_p->filter_str[chan][MAX_CHANS]); //#endif return; } } /* Gather statistics. */ stats_rf_recv_packets++; /* * First make a copy of it because it might be modified in place. */ pp = ax25_dup (recv_pp); assert (pp != NULL); /* * Third party frames require special handling to unwrap payload. */ while (ax25_get_dti(pp) == '}') { packet_t inner_pp; for (n = 0; n < ax25_get_num_repeaters(pp); n++) { char via[AX25_MAX_ADDR_LEN]; /* includes ssid. Do we want to ignore it? */ ax25_get_addr_with_ssid (pp, n + AX25_REPEATER_1, via); if (strcmp(via, "TCPIP") == 0 || strcmp(via, "TCPXX") == 0 || strcmp(via, "RFONLY") == 0 || strcmp(via, "NOGATE") == 0) { #if DEBUGx text_color_set(DW_COLOR_DEBUG); dw_printf ("Rx IGate: Do not relay with TCPIP etc. in path.\n"); #endif ax25_delete (pp); return; } } #if DEBUGx text_color_set(DW_COLOR_DEBUG); dw_printf ("Rx IGate: Unwrap third party message.\n"); #endif inner_pp = ax25_unwrap_third_party(pp); if (inner_pp == NULL) { ax25_delete (pp); return; } ax25_delete (pp); pp = inner_pp; } /* * Do not relay packets with TCPIP, TCPXX, RFONLY, or NOGATE in the via path. */ for (n = 0; n < ax25_get_num_repeaters(pp); n++) { char via[AX25_MAX_ADDR_LEN]; /* includes ssid. Do we want to ignore it? */ ax25_get_addr_with_ssid (pp, n + AX25_REPEATER_1, via); if (strcmp(via, "TCPIP") == 0 || strcmp(via, "TCPXX") == 0 || strcmp(via, "RFONLY") == 0 || strcmp(via, "NOGATE") == 0) { #if DEBUGx text_color_set(DW_COLOR_DEBUG); dw_printf ("Rx IGate: Do not relay with TCPIP etc. in path.\n"); #endif ax25_delete (pp); return; } } /* * Do not relay generic query. */ if (ax25_get_dti(pp) == '?') { #if DEBUGx text_color_set(DW_COLOR_DEBUG); dw_printf ("Rx IGate: Do not relay generic query.\n"); #endif ax25_delete (pp); return; } /* * Cut the information part at the first CR or LF. */ info_len = ax25_get_info (pp, &pinfo); if ((p = strchr ((char*)pinfo, '\r')) != NULL) { #if DEBUGx text_color_set(DW_COLOR_DEBUG); dw_printf ("Rx IGate: Truncated information part at CR.\n"); #endif *p = '\0'; } if ((p = strchr ((char*)pinfo, '\n')) != NULL) { #if DEBUGx text_color_set(DW_COLOR_DEBUG); dw_printf ("Rx IGate: Truncated information part at LF.\n"); #endif *p = '\0'; } /* * Someone around here occasionally sends a packet with no information part. */ if (strlen((char*)pinfo) == 0) { #if DEBUGx text_color_set(DW_COLOR_DEBUG); dw_printf ("Rx IGate: Information part length is zero.\n"); #endif ax25_delete (pp); return; } // TODO: Should we drop raw touch tone data object type generated here? /* * Do not relay if a duplicate of something sent recently. */ if ( ! rx_to_ig_allow(pp)) { #if DEBUG text_color_set(DW_COLOR_DEBUG); dw_printf ("Rx IGate: Drop duplicate of same packet seen recently.\n"); #endif ax25_delete (pp); return; } /* * Finally, append ",qAR," and my call to the path. */ ax25_format_addrs (pp, msg); msg[strlen(msg)-1] = '\0'; /* Remove trailing ":" */ strlcat (msg, ",qAR,", sizeof(msg)); strlcat (msg, save_audio_config_p->achan[chan].mycall, sizeof(msg)); strlcat (msg, ":", sizeof(msg)); strlcat (msg, (char*)pinfo, sizeof(msg)); strlcat (msg, "\r\n", sizeof(msg)); send_msg_to_server (msg); stats_rx_igate_packets++; /* * Remember what was sent to avoid duplicates in near future. */ rx_to_ig_remember (pp); ax25_delete (pp); } /* end igate_send_rec_packet */ /*------------------------------------------------------------------- * * Name: send_msg_to_server * * Purpose: Send to the IGate server. * This one function should be used for login, hearbeats, * and packets. * * Inputs: msg - Message. Should end with CR/LF. * * * Description: Send message to IGate Server if connected. * Disconnect from server, and notify user, if any error. * *--------------------------------------------------------------------*/ static void send_msg_to_server (char *msg) { int err; if (igate_sock == -1) { return; /* Silently discard if not connected. */ } stats_uplink_bytes += strlen(msg); #if DEBUG text_color_set(DW_COLOR_XMIT); dw_printf ("[ig] "); ax25_safe_print (msg, strlen(msg), 0); dw_printf ("\n"); #endif #if __WIN32__ err = send (igate_sock, msg, strlen(msg), 0); if (err == SOCKET_ERROR) { text_color_set(DW_COLOR_ERROR); dw_printf ("\nError %d sending message to IGate server. Closing connection.\n\n", WSAGetLastError()); //dw_printf ("DEBUG: igate_sock=%d, line=%d\n", igate_sock, __LINE__); closesocket (igate_sock); igate_sock = -1; WSACleanup(); } #else err = write (igate_sock, msg, strlen(msg)); if (err <= 0) { text_color_set(DW_COLOR_ERROR); dw_printf ("\nError sending message to IGate server. Closing connection.\n\n"); close (igate_sock); igate_sock = -1; } #endif } /* end send_msg_to_server */ /*------------------------------------------------------------------- * * Name: get1ch * * Purpose: Read one byte from socket. * * Inputs: igate_sock - file handle for socket. * * Returns: One byte from stream. * Waits and tries again later if any error. * * *--------------------------------------------------------------------*/ static int get1ch (void) { unsigned char ch; int n; while (1) { while (igate_sock == -1) { SLEEP_SEC(5); /* Not connected. Try again later. */ } /* Just get one byte at a time. */ // TODO: might read complete packets and unpack from own buffer // rather than using a system call for each byte. #if __WIN32__ n = recv (igate_sock, (char*)(&ch), 1, 0); #else n = read (igate_sock, &ch, 1); #endif if (n == 1) { #if DEBUG9 dw_printf (log_fp, "%02x %c %c", ch, isprint(ch) ? ch : '.' , (isupper(ch>>1) || isdigit(ch>>1) || (ch>>1) == ' ') ? (ch>>1) : '.'); if (ch == '\r') fprintf (log_fp, " CR"); if (ch == '\n') fprintf (log_fp, " LF"); fprintf (log_fp, "\n"); #endif return(ch); } text_color_set(DW_COLOR_ERROR); dw_printf ("\nError reading from IGate server. Closing connection.\n\n"); #if __WIN32__ closesocket (igate_sock); #else close (igate_sock); #endif igate_sock = -1; } } /* end get1ch */ /*------------------------------------------------------------------- * * Name: igate_recv_thread * * Purpose: Wait for messages from IGate Server. * * Inputs: arg - Not used. * * Outputs: igate_sock - File descriptor for communicating with client app. * * Description: Process messages from the IGate server. * *--------------------------------------------------------------------*/ #if __WIN32__ static unsigned __stdcall igate_recv_thread (void *arg) #else static void * igate_recv_thread (void *arg) #endif { unsigned char ch; unsigned char message[1000]; // Spec says max 500 or so. int len; #if DEBUGx text_color_set(DW_COLOR_DEBUG); dw_printf ("igate_recv_thread ( socket = %d )\n", igate_sock); #endif while (1) { len = 0; do { ch = get1ch(); stats_downlink_bytes++; if (len < sizeof(message)) { message[len] = ch; } len++; } while (ch != '\n'); /* * We have a complete message terminated by LF. */ if (len == 0) { /* * Discard if zero length. */ } else if (message[0] == '#') { /* * Heartbeat or other control message. * * Print only if within seconds of logging in. * That way we can see login confirmation but not * be bothered by the heart beat messages. */ #ifndef DEBUG if ( ! ok_to_send) { #endif text_color_set(DW_COLOR_REC); dw_printf ("[ig] "); ax25_safe_print ((char *)message, len, 0); dw_printf ("\n"); #ifndef DEBUG } #endif } else { /* * Convert to third party packet and transmit. */ text_color_set(DW_COLOR_REC); dw_printf ("\n[ig] "); ax25_safe_print ((char *)message, len, 0); dw_printf ("\n"); /* * Remove CR LF from end. */ if (len >=2 && message[len-1] == '\n') { message[len-1] = '\0'; len--; } if (len >=1 && message[len-1] == '\r') { message[len-1] = '\0'; len--; } xmit_packet ((char*)message); } } /* while (1) */ return (0); } /* end igate_recv_thread */ /*------------------------------------------------------------------- * * Name: xmit_packet * * Purpose: Convert text string, from IGate server, to third party * packet and send to transmit queue. * * Inputs: message - As sent by the server. * *--------------------------------------------------------------------*/ static void xmit_packet (char *message) { packet_t pp3; char payload[AX25_MAX_PACKET_LEN]; /* what is max len? */ char *pinfo = NULL; int info_len; int to_chan = save_igate_config_p->tx_chan; /* Should be -1 if not configured for xmit!!! */ /* Future: Array of boolean to allow multiple xmit channels? */ /* * Is IGate to Radio direction enabled? */ if (to_chan == -1) { return; } stats_tx_igate_packets++; assert (to_chan >= 0 && to_chan < MAX_CHANS); /* * Try to parse it into a packet object. * Bug: Up to 8 digipeaters are allowed in radio format. * There is a potential of finding a larger number here. */ pp3 = ax25_from_text(message, 0); if (pp3 == NULL) { text_color_set(DW_COLOR_ERROR); dw_printf ("Tx IGate: Could not parse message from server.\n"); dw_printf ("%s\n", message); return; } /* * Apply our own packet filtering if configured. */ assert (to_chan >= 0 && to_chan < MAX_CHANS); if (save_digi_config_p->filter_str[MAX_CHANS][to_chan] != NULL) { if (pfilter(MAX_CHANS, to_chan, save_digi_config_p->filter_str[MAX_CHANS][to_chan], pp3) != 1) { // TODO1.2: take out debug message. One person liked it as a confirmation of what was going on. // Maybe it should be part of a more comprehensive debug facility? //#if DEBUG text_color_set(DW_COLOR_DEBUG); dw_printf ("Packet from IGate to channel %d was rejected by filter: %s\n", to_chan, save_digi_config_p->filter_str[MAX_CHANS][to_chan]); //#endif ax25_delete (pp3); return; } } /* * TODO: Discard if qAX in path??? others? */ /* * Remove the VIA path. */ while (ax25_get_num_repeaters(pp3) > 0) { ax25_remove_addr (pp3, AX25_REPEATER_1); } /* * Replace the VIA path with TCPIP and my call. * Mark my call as having been used. */ ax25_set_addr (pp3, AX25_REPEATER_1, "TCPIP"); ax25_set_h (pp3, AX25_REPEATER_1); ax25_set_addr (pp3, AX25_REPEATER_2, save_audio_config_p->achan[save_igate_config_p->tx_chan].mycall); ax25_set_h (pp3, AX25_REPEATER_2); /* * Convert to text representation. */ memset (payload, 0, sizeof(payload)); ax25_format_addrs (pp3, payload); info_len = ax25_get_info (pp3, (unsigned char **)(&pinfo)); strlcat (payload, pinfo, sizeof(payload)); #if DEBUGx text_color_set(DW_COLOR_DEBUG); dw_printf ("Tx IGate: payload=%s\n", payload); #endif /* * Encapsulate for sending over radio if no reason to drop it. */ if (ig_to_tx_allow (pp3)) { char radio [500]; packet_t pradio; snprintf (radio, sizeof(radio), "%s>%s%d%d%s:}%s", save_audio_config_p->achan[save_igate_config_p->tx_chan].mycall, APP_TOCALL, MAJOR_VERSION, MINOR_VERSION, save_igate_config_p->tx_via, payload); pradio = ax25_from_text (radio, 1); /* Oops. Didn't have a check for NULL here. */ /* Could this be the cause of rare and elusive crashes in 1.2? */ if (pradio != NULL) { #if ITEST text_color_set(DW_COLOR_XMIT); dw_printf ("Xmit: %s\n", radio); ax25_delete (pradio); #else /* This consumes packet so don't reference it again! */ tq_append (save_igate_config_p->tx_chan, TQ_PRIO_1_LO, pradio); #endif stats_rf_xmit_packets++; ig_to_tx_remember (pp3); } else { text_color_set(DW_COLOR_ERROR); dw_printf ("Received invalid packet from IGate.\n"); dw_printf ("%s\n", payload); dw_printf ("Will not attempt to transmit third party packet.\n"); dw_printf ("%s\n", radio); } } ax25_delete (pp3); } /* end xmit_packet */ /*------------------------------------------------------------------- * * Name: rx_to_ig_remember * * Purpose: Keep a record of packets sent to the IGate server * so we don't send duplicates within some set amount of time. * * Inputs: pp - Pointer to a packet object. * *------------------------------------------------------------------- * * Name: rx_to_ig_allow * * Purpose: Check whether this is a duplicate of another sent recently. * * Input: pp - Pointer to packet object. * * Returns: True if it is OK to send. * *------------------------------------------------------------------- * * Description: These two functions perform the final stage of filtering * before sending a received (from radio) packet to the IGate server. * * rx_to_ig_remember must be called for every packet sent to the server. * * rx_to_ig_allow decides whether this should be allowed thru * based on recent activity. We will drop the packet if it is a * duplicate of another sent recently. * * Rather than storing the entire packet, we just keep a CRC to * reduce memory and processing requirements. We do the same in * the digipeater function to suppress duplicates. * * There is a 1 / 65536 chance of getting a false positive match * which is good enough for this application. * *--------------------------------------------------------------------*/ #define RX2IG_DEDUPE_TIME 60 /* Do not send duplicate within 60 seconds. */ #define RX2IG_HISTORY_MAX 30 /* Remember the last 30 sent to IGate server. */ static int rx2ig_insert_next; static time_t rx2ig_time_stamp[RX2IG_HISTORY_MAX]; static unsigned short rx2ig_checksum[RX2IG_HISTORY_MAX]; static void rx_to_ig_init (void) { int n; for (n=0; n= RX2IG_HISTORY_MAX) { rx2ig_insert_next = 0; } } static int rx_to_ig_allow (packet_t pp) { unsigned short crc = ax25_dedupe_crc(pp); time_t now = time(NULL); int j; for (j=0; j= now - RX2IG_DEDUPE_TIME && rx2ig_checksum[j] == crc) { return 0; } } return 1; } /* end rx_to_ig_allow */ /*------------------------------------------------------------------- * * Name: ig_to_tx_remember * * Purpose: Keep a record of packets sent from IGate server to radio transmitter * so we don't send duplicates within some set amount of time. * * Inputs: pp - Pointer to a packet object. * *------------------------------------------------------------------------------ * * Name: ig_to_tx_allow * * Purpose: Check whether this is a duplicate of another sent recently * or if we exceed the transmit rate limits. * * Input: pp - Pointer to packet object. * * Returns: True if it is OK to send. * *------------------------------------------------------------------------------ * * Description: These two functions perform the final stage of filtering * before sending a packet from the IGate server to the radio. * * ig_to_tx_remember must be called for every packet, from the IGate * server, sent to the radio transmitter. * * ig_to_tx_allow decides whether this should be allowed thru * based on recent activity. We will drop the packet if it is a * duplicate of another sent recently. * * This is the essentially the same as the pair of functions * above with one addition restriction. * * The typical residential Internet connection is about 10,000 * times faster than the radio links we are using. It would * be easy to completely saturate the radio channel if we are * not careful. * * Besides looking for duplicates, this will also tabulate the * number of packets sent during the past minute and past 5 * minutes and stop sending if a limit is reached. * * Future? We might also want to avoid transmitting if the same packet * was heard on the radio recently. If everything is kept in * the same table, we'd need to distinguish between those from * the IGate server and those heard on the radio. * Those heard on the radio would not count toward the * 1 and 5 minute rate limiting. * Maybe even provide informative information such as - * Tx IGate: Same packet heard recently from W1ABC and W9XYZ. * * Of course, the radio encapsulation would need to be removed * and only the 3rd party packet inside compared. * *--------------------------------------------------------------------*/ #define IG2TX_DEDUPE_TIME 60 /* Do not send duplicate within 60 seconds. */ #define IG2TX_HISTORY_MAX 50 /* Remember the last 50 sent from server to radio. */ static int ig2tx_insert_next; static time_t ig2tx_time_stamp[IG2TX_HISTORY_MAX]; static unsigned short ig2tx_checksum[IG2TX_HISTORY_MAX]; static void ig_to_tx_init (void) { int n; for (n=0; n= IG2TX_HISTORY_MAX) { ig2tx_insert_next = 0; } } static int ig_to_tx_allow (packet_t pp) { unsigned short crc = ax25_dedupe_crc(pp); time_t now = time(NULL); int j; int count_1, count_5; for (j=0; j= now - IG2TX_DEDUPE_TIME && ig2tx_checksum[j] == crc) { text_color_set(DW_COLOR_INFO); dw_printf ("Tx IGate: Drop duplicate packet transmitted recently.\n"); return 0; } } count_1 = 0; count_5 = 0; for (j=0; j= now - 60) count_1++; if (ig2tx_time_stamp[j] >= now - 300) count_5++; } if (count_1 >= save_igate_config_p->tx_limit_1) { text_color_set(DW_COLOR_ERROR); dw_printf ("Tx IGate: Already transmitted maximum of %d packets in 1 minute.\n", save_igate_config_p->tx_limit_1); return 0; } if (count_5 >= save_igate_config_p->tx_limit_5) { text_color_set(DW_COLOR_ERROR); dw_printf ("Tx IGate: Already transmitted maximum of %d packets in 5 minutes.\n", save_igate_config_p->tx_limit_5); return 0; } return 1; } /* end ig_to_tx_allow */ /* end igate.c */