Added experimental telnet outbound code

ChangeLog

@@ -2,6 +2,10 @@ $Id$
 
 v0.39.9		29-Jan-2004
 
+	mbcico:
+		Added experimental code for telnet outbound connections. This
+		code is not compiled by default so don't worry or bother.
+
 
 v0.39.8		26-Jan-2004 - 29-Jan-2004
 

TODO

@@ -124,6 +124,8 @@ mbcico:
 
 	N: Implement PLZ turn off m_get command.
 
+	N: Make workaround for binkp bug in Irex 2.24 upto 2.29
+
 mbfile:
 	L: Add a check to see if the magic filenames are (still) valid.
 

lib/libs.h

@@ -86,6 +86,7 @@
 #ifdef	HAVE_ZLIB_H
 #include <zlib.h>
 #endif
+#include <pthread.h>
 
 #pragma pack(1)
 

mbcico/call.c

@@ -181,9 +181,11 @@ int call(faddr *addr)
 		tcp_mode = TCPMODE_IBN;
 	    } else if (strcmp(protocol, "fido") == 0) {
 		tcp_mode = TCPMODE_IFC;
-//	    } else if (strcmp(protocol, "telnet") == 0) {
+#ifdef USE_EXPERIMENT
-//		tcp_mode = TCPMODE_ITN;
+	    } else if (strcmp(protocol, "telnet") == 0) {
-//		telnet = TRUE;
+		tcp_mode = TCPMODE_ITN;
+		telnet = TRUE;
+#endif
 	    } else {
 		Syslog('+', "No common TCP/IP protocols for node %s", nlent->name);
 		free(inetaddr);

mbcico/mbcico.c

@@ -369,11 +369,17 @@ int main(int argc, char *argv[])
 	/*
 	 * Slave (answer) mode
 	 */
+#ifdef USE_EXPERIMENT
+	if (telnet) {
+	    Syslog('-', "Will use experimental telnet code");
+	}
+#else
 	if (telnet) {
 	    WriteError("Answering calls with the \"-t itn\" option no longer supported");
 	    WriteError("Install mbtelind to answer incoming telnet calls");
 	    die(MBERR_COMMANDLINE);
 	}
+#endif
 	if (!answermode && tcp_mode == TCPMODE_IBN)
 	    answermode = xstrcpy((char *)"ibn");
 	rc = maxrc = answer(answermode);

mbcico/opentcp.c

@@ -61,6 +61,13 @@ extern long	rcvdbytes;
 extern int	Loaded;
 static int	tcp_is_open = FALSE;
 
+#ifdef USE_EXPERIMENT
+void telnet_init(int);
+void telnet_answer(int, int, int);
+void telout_filter(int [], int);
+void telin_filter(int [], int);
+#endif
+
 
 /* opentcp() was rewritten by Martin Junius */
 
@@ -68,10 +75,12 @@ int opentcp(char *name)
 {
     struct servent	*se;
     struct hostent	*he;
-    int			a1, a2, a3, a4, Fd, GotPort = FALSE;
+    struct sockaddr_in  server;
+    int			a1, a2, a3, a4, rc, Fd, Fdo, GotPort = FALSE;
     char		*errmsg, *portname;
     short		portnum;
-    struct sockaddr_in	server;
+    int			input_pipe[2], output_pipe[2];
+    pid_t		fpid;
 
     Syslog('+', "Open TCP connection to \"%s\"", MBSE_SS(name));
 
@@ -102,11 +111,13 @@ int opentcp(char *name)
 				else
 				    server.sin_port = htons(FIDOPORT);
 				break;
-//	    case TCPMODE_ITN:   if ((se = getservbyname("telnet", "tcp")))
+#ifdef USE_EXPERIMENT
-//				    server.sin_port = se->s_port;
+	    case TCPMODE_ITN:   if ((se = getservbyname("telnet", "tcp")))
-//				else
+				    server.sin_port = se->s_port;
-//				    server.sin_port = htons(TELNPORT);
+				else
-//				break;
+				    server.sin_port = htons(TELNPORT);
+				break;
+#endif
 	    case TCPMODE_IBN:	if ((se = getservbyname("binkd", "tcp")))
 				    server.sin_port = se->s_port;
 				else
@@ -134,6 +145,98 @@ int opentcp(char *name)
 	return -1;
     }
 
+#ifdef USE_EXPERIMENT
+    if (tcp_mode == TCPMODE_ITN) {
+	Syslog('s', "Installing telnet filter...");
+
+	Syslog('d', "SIGPIPE => sigpipe()");
+	signal(SIGPIPE, sigpipe);
+	Syslog('d', "SIGHUP => linedrop()");
+	signal(SIGHUP, linedrop);
+
+	/*
+	 * Create TCP socket and open
+	 */
+	if ((Fdo = socket(AF_INET,SOCK_STREAM,0)) == -1) {
+	    WriteError("$Cannot create socket");
+	    return -1;
+	}
+	if (connect(Fdo,(struct sockaddr *)&server,sizeof(server)) == -1) {
+	    Syslog('+', "Cannot connect %s",inet_ntoa(server.sin_addr));
+	    return -1;
+	}
+	Syslog('s', "socket %d", Fdo);
+
+	fflush(stdin);
+	fflush(stdout);
+	setbuf(stdin,NULL);
+	setbuf(stdout, NULL);
+	close(0);
+	close(1);
+
+	/*
+	 * Create output pipe
+	 */
+	if ((rc = pipe(output_pipe)) == -1) {
+	    WriteError("$could not create output_pipe");
+	    return -1;
+	}
+
+	fpid = fork();
+	switch (fpid) {
+	    case -1:    WriteError("fork for telout_filter failed");
+			return -1;
+	    case 0:     if (close(output_pipe[1]) == -1) {
+			    WriteError("$error close output_pipe[1]");
+			    return -1;
+			}
+			telout_filter(output_pipe, Fdo);
+			/* NOT REACHED */
+	}
+	if (close(output_pipe[0] == -1)) {
+	    WriteError("$error close output_pipe[0]");
+	    return -1;
+	}
+	Syslog('s', "telout_filter forked with pid %d", fpid);
+
+	/*
+	 * Create input pipe
+	 */
+	if ((rc = pipe(input_pipe)) == -1) {
+	    WriteError("$could not create input_pipe");
+	    return -1;
+	}
+
+	/*
+	 * Fork input filter
+	 */
+	fpid = fork();
+	switch (fpid) {
+	    case -1:    WriteError("fork for telin_filter failed");
+			return -1;
+	    case 0:	if (close(input_pipe[0]) == -1) {
+			    WriteError("$error close input_pipe[0]");
+			    return -1;
+			}
+			telin_filter(input_pipe, Fdo);
+			/* NOT REACHED */
+	}
+	if (close(input_pipe[1]) == -1) {
+	    WriteError("$error close input_pipe[1]");
+	    return -1;
+	}
+	Syslog('s', "telin_filter forked with pid %d", fpid);
+	Syslog('s', "stdout = %d", output_pipe[1]);
+	Syslog('s', "stdin  = %d", input_pipe[0]);
+
+	telnet_init(Fdo);
+	f_flags=0;
+
+    } else {
+#endif
+	/*
+	 * Transparant 8 bits connection
+	 */
 	Syslog('d', "SIGPIPE => sigpipe()");
 	signal(SIGPIPE, sigpipe);
 	Syslog('d', "SIGHUP => linedrop()");
@@ -144,8 +247,9 @@ int opentcp(char *name)
 	setbuf(stdout,NULL);
 	close(0);
 	close(1);
+
 	if ((Fd = socket(AF_INET,SOCK_STREAM,0)) != 0) {
-	WriteError("$Cannot create socket (got %d, expected 0");
+	    WriteError("$Cannot create socket (got %d, expected 0)", Fd);
 	    open("/dev/null",O_RDONLY);
 	    open("/dev/null",O_WRONLY);
 	    return -1;
@@ -163,9 +267,12 @@ int opentcp(char *name)
 	}
 
 	f_flags=0;
+#ifdef USE_EXPERIMENT
+    }
+#endif
 
     Syslog('+', "Established %s/TCP connection with %s, port %d", 
-	(tcp_mode == TCPMODE_IFC) ? "IFC":(tcp_mode == TCPMODE_IBN) ? "IBN":"Unknown",
+	(tcp_mode == TCPMODE_IFC) ? "IFC":(tcp_mode == TCPMODE_ITN) ?"ITN":(tcp_mode == TCPMODE_IBN) ? "IBN":"Unknown",
 	inet_ntoa(server.sin_addr), (int)ntohs(server.sin_port));
     c_start = time(NULL);
     carrier = TRUE;
@@ -183,6 +290,14 @@ void closetcp(void)
     if (!tcp_is_open)
 	return;
 
+#ifdef USE_EXPERIMENT
+    if (tcp_mode == TCPMODE_ITN) {
+	/*
+	 * Check if telout thread is running
+	 */
+    }
+#endif
+
     shutdown(fd, 2);
     Syslog('d', "SIGHUP => SIG_IGN");
     signal(SIGHUP, SIG_IGN);
@@ -218,3 +333,135 @@ void closetcp(void)
 }
 
 
+
+#ifdef USE_EXPERIMENT
+
+
+void telnet_init(int Fd)
+{
+    Syslog('s', "telnet_init(%d)", Fd);
+    telnet_answer(DO, TOPT_SUPP, Fd);
+    telnet_answer(WILL, TOPT_SUPP, Fd);
+    telnet_answer(DO, TOPT_BIN, Fd);
+    telnet_answer(WILL, TOPT_BIN, Fd);
+    telnet_answer(DO, TOPT_ECHO, Fd);
+    telnet_answer(WILL, TOPT_ECHO, Fd);
+}
+
+
+
+void telnet_answer(int tag, int opt, int Fd)
+{
+    char    buf[3];
+    char    *r = (char *)"???";
+	            
+    switch (tag) {
+	case WILL:  r = (char *)"WILL";
+		    break;
+	case WONT:  r = (char *)"WONT";
+		    break;
+	case DO:    r = (char *)"DO";
+		    break;
+	case DONT:  r = (char *)"DONT";
+		    break;
+    }
+    Syslog('s', "Telnet: send %s %d", r, opt);
+
+    buf[0] = IAC;
+    buf[1] = tag;
+    buf[2] = opt;
+    if (write (Fd, buf, 3) != 3)
+	WriteError("$answer cant send");
+}
+
+
+
+void telout_filter(int output_pipe[], int Fd)
+{
+    int	    rc, c;
+    char    ch;
+
+    Syslog('s', "telout_filter: in=%d out=%d", output_pipe[0], Fd);
+
+    while (read(output_pipe[0], &ch, 1) > 0) {
+	c = (int)ch & 0xff;
+//	Syslog('s', "telout_filter: ch=%s", printablec(c));
+	if (c == IAC) {
+	    Syslog('s', "telout_filter: got IAC");
+	    /*
+	     * Escape IAC characters
+	     */
+	    rc = write(Fd, &ch, 1);
+	}
+	/* write translated character back to user_handler. */
+	rc = write(Fd, &ch, 1);
+	if (rc == -1) { /* write failed - notify user and exit. */
+	    Syslog('s', "$telout_filter: write to Fd failed");
+	    exit(1);
+	}
+    }
+    Syslog('s', "$telout_filter: read error");
+
+    exit(0);
+}
+
+
+void telin_filter(int input_pipe[], int Fd)
+{
+    int     rc, c, m;
+    char    ch;
+
+    Syslog('s', "telin_filter: in=%d out=%d", Fd, input_pipe[1]);
+    Syslog('s', "telin_filter: IAC=%s %d", printablec(IAC), IAC);
+
+    while (read(Fd, &ch, 1) > 0) {
+	c = (int)ch & 0xff;
+//	Syslog('s', "telin_filter: ch=%s", printablec(c));
+	if (c == IAC) {
+	    Syslog('s', "got IAC");
+	    if ((read(Fd, &ch, 1) < 0))
+		break;
+	    m = (int)ch & 0xff;
+	    switch (m) {
+		case WILL:  read(Fd, &ch, 1);
+			    m = (int)ch & 0xff;
+			    Syslog('s', "Telnet: recv WILL %d", m);
+			    if (m != TOPT_BIN && m != TOPT_SUPP && m != TOPT_ECHO)
+				telnet_answer(DONT, m, input_pipe[1]);
+			    break;
+		case WONT:  read(Fd, &ch, 1);
+			    m = (int)ch & 0xff;
+			    Syslog('s', "Telnet: recv WONT %d", m);
+			    break;
+		case DO:    read(Fd, &ch, 1);
+			    m = (int)ch & 0xff;
+			    Syslog('s', "Telnet: recv DO %d", m);
+			    if (m != TOPT_BIN && m != TOPT_SUPP && m != TOPT_ECHO)
+				telnet_answer(WONT, m, input_pipe[1]);
+			    break;
+		case DONT:  read(Fd, &ch, 1);
+			    m = (int)ch & 0xff;
+			    Syslog('s', "Telnet: recv DONT %d", m);
+			    break;
+		case IAC:   ch = (char)m & 0xff;
+			    rc = write(input_pipe[1], &ch, 1);
+			    break;
+		default:    Syslog('s', "Telnet: recv IAC %d, not good", m);
+			    break;
+	    }
+	} else {
+//	    Syslog('s', "Telnet: normal");
+	    ch = (char)c;
+	    rc = write(input_pipe[1], &ch, 1);
+	    if (rc == -1) { /* write failed - notify user and exit. */
+		Syslog('s', "$telin_filter: write to input_pipe[1] failed");
+		exit(1);
+	    }
+	}
+    }
+    Syslog('s', "$telin_filter: read error");
+
+    exit(0);
+}
+
+#endif

mbcico/opentcp.h

@@ -3,6 +3,13 @@
 #ifndef	_OPENTCP_H
 #define	_OPENTCP_H
 
+#define MBT_TIMEOUT 500
+#define MBT_BUFLEN  8192
+
+#define TOPT_BIN                0
+#define TOPT_ECHO               1
+#define TOPT_SUPP               3
+
 int  opentcp(char *);
 void closetcp(void);
 

mbcico/session.c

@@ -110,6 +110,11 @@ int session(faddr *a, node *nl, int role, int tp, char *dt)
 	    }
 	}
 	session_flags |= SESSION_TCP;
+#ifdef USE_EXPERIMENT
+	if ((tcp_mode == TCPMODE_ITN) && (role == 0)) {
+	    Syslog('-', "Will need to install telnet receiver thread");
+	}
+#endif
     }
 
     if (data)