bail out if encryption has been requested but could not be enabled

git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@10801 ec53bebd-3082-4978-b11e-865c3cabbd6b

appl/telnet/telnet/authenc.c

@@ -62,7 +62,14 @@ net_encrypt(void)
 int
 telnet_spin(void)
 {
-	return(-1);
+    extern int scheduler_lockout_tty;
+
+    scheduler_lockout_tty = 1;
+    Scheduler(0);
+    scheduler_lockout_tty = 0;
+    
+    return 0;
+
 }
 
 char *

appl/telnet/telnet/externs.h

@@ -66,6 +66,7 @@ extern int
     localchars,		/* we recognize interrupt/quit */
     donelclchars,	/* the user has set "localchars" */
     showoptions,
+    wantencryption,	/* User has requested encryption */
     net,		/* Network file descriptor */
     tin,		/* Terminal input file descriptor */
     tout,		/* Terminal output file descriptor */
@@ -81,6 +82,8 @@ extern int
     termdata,		/* Print out terminal data flow */
     debug;		/* Debug level */
 
+extern int intr_happened, intr_waiting;	/* for interrupt handling */
+
 extern cc_t escape;	/* Escape to command mode */
 extern cc_t rlogin;	/* Rlogin mode escape character */
 #ifdef	KLUDGELINEMODE

appl/telnet/telnet/main.c

@@ -126,6 +126,7 @@ krb5_init(void)
         "libdefaults", "encrypt", NULL)) {
           encrypt_auto(1);
           decrypt_auto(1); 
+	  wantencryption = 1;
           EncryptVerbose(1);
         }
 #endif
@@ -295,6 +296,7 @@ main(int argc, char **argv)
 #ifdef	ENCRYPTION
 			encrypt_auto(1);
 			decrypt_auto(1);
+			wantencryption = 1;
 			EncryptVerbose(1);
 #else
 			fprintf(stderr,

appl/telnet/telnet/sys_bsd.c

@@ -651,10 +651,17 @@ deadpeer(int sig)
 	longjmp(peerdied, -1);
 }
 
+int intr_happened = 0;
+int intr_waiting = 0;
+
     /* ARGSUSED */
 static RETSIGTYPE
 intr(int sig)
 {
+    if (intr_waiting) {
+	intr_happened = 1;
+	return;
+    }
     if (localchars) {
 	intp();
 	return;

appl/telnet/telnet/telnet.1

@@ -177,8 +177,10 @@ In this
 mode, the escape character is set to the tilde (~) character,
 unless modified by the -e option.
 .It Fl x
-Turns on encryption of the data stream if possible. This is 
-currently the default and when it fails a warning is issued.
+Turn on encryption of the data stream.  When this option is turned on,
+.B telnet
+will exit with an error if authentication cannot be negotiated or if
+encryption cannot be turned on.
 .It Ar host
 Indicates the official name, an alias, or the Internet address
 of a remote host.

appl/telnet/telnet/telnet.c

@@ -70,6 +70,7 @@ int
 	netdata,	/* Print out network data flow */
 	crlf,		/* Should '\r' be mapped to <CR><LF> (or <CR><NUL>)? */
 	telnetport,
+        wantencryption = 0,
 	SYNCHing,	/* we are in TELNET SYNCH mode */
 	flushout,	/* flush output */
 	autoflush = 0,	/* flush output when interrupting? */
@@ -84,6 +85,8 @@ int
 
 char *prompt = 0;
 
+int scheduler_lockout_tty = 0;
+
 cc_t escape;
 cc_t rlogin;
 #ifdef	KLUDGELINEMODE
@@ -1957,7 +1960,7 @@ telsnd()
  */
 
 
-static int
+    int
 Scheduler(int block) /* should we block in the select ? */
 {
 		/* One wants to be a bit careful about setting returnValue
@@ -1988,6 +1991,10 @@ Scheduler(int block) /* should we block in the select ? */
 
     /* If we have seen a signal recently, reset things */
 
+    if (scheduler_lockout_tty) {
+        ttyin = ttyout = 0;
+    }
+
     /* Call to system code to process rings */
 
     returnValue = process_rings(netin, netout, netex, ttyin, ttyout, !block);
@@ -2010,6 +2017,8 @@ Scheduler(int block) /* should we block in the select ? */
 void
 my_telnet(char *user)
 {
+    int printed_encrypt = 0;
+    
     sys_telnet_init();
 
 #if	defined(AUTHENTICATION) || defined(ENCRYPTION)
@@ -2048,6 +2057,64 @@ my_telnet(char *user)
 	    tel_enter_binary(binary);
     }
 
+#ifdef ENCRYPTION
+    /*
+     * Note: we assume a tie to the authentication option here.  This
+     * is necessary so that authentication fails, we don't spin
+     * forever. 
+     */
+    if (wantencryption) {
+	extern int auth_has_failed;
+	time_t timeout = time(0) + 60;
+
+	send_do(TELOPT_ENCRYPT, 1);
+	send_will(TELOPT_ENCRYPT, 1);
+	while (1) {
+	    if (my_want_state_is_wont(TELOPT_AUTHENTICATION)) {
+		printf("\nServer refused to negotiate authentication,\n");
+		printf("which is required for encryption.\n");
+		Exit(1);
+	    }
+	    if (auth_has_failed) {
+		printf("\nAuthentication negotation has failed,\n");
+		printf("which is required for encryption.\n");
+		Exit(1);
+	    }
+	    if (my_want_state_is_dont(TELOPT_ENCRYPT) ||
+		my_want_state_is_wont(TELOPT_ENCRYPT)) {
+		printf("\nServer refused to negotiate encryption.\n");
+		Exit(1);
+	    }
+	    if (encrypt_is_encrypting())
+		break;
+	    if (time(0) > timeout) {
+		printf("\nEncryption could not be enabled.\n");
+		Exit(1);
+	    }
+	    if (printed_encrypt == 0) {
+		    printed_encrypt = 1;
+		    printf("Waiting for encryption to be negotiated...\n");
+		    /*
+		     * Turn on MODE_TRAPSIG and then turn off localchars 
+		     * so that ^C will cause telnet to exit.
+		     */
+		    TerminalNewMode(getconnmode()|MODE_TRAPSIG);
+		    intr_waiting = 1;
+	    }
+	    if (intr_happened) {
+		    printf("\nUser interrupt.\n");
+		    Exit(1);
+	    }
+	    telnet_spin();
+	}
+	if (printed_encrypt) {
+		printf("done.\n");
+		intr_waiting = 0;
+		setconnmode(0);
+	}
+    }
+#endif
+
     for (;;) {
 	int schedValue;
 

appl/telnet/telnet/telnet_locl.h

@@ -138,6 +138,10 @@
 #include <netinet/ip.h>
 #endif
 #ifdef HAVE_ARPA_INET_H
+#ifdef _AIX
+struct sockaddr_dl; /* AIX fun */
+struct ether_addr;
+#endif
 #include <arpa/inet.h>
 #endif