From b10946c96d87e3de3a5a3ea166ef365d30a9bc9d Mon Sep 17 00:00:00 2001
From: Sean Middleditch <sean@middleditch.us>
Date: Sun, 22 Mar 2009 18:21:14 -0400
Subject: [PATCH] dont use a separate event for ZMP

---
 README         | 26 +++++++++++++-------
 libtelnet.c    | 66 ++++++++++++++++++++++++++++++--------------------
 libtelnet.h    |  1 -
 telnet-proxy.c | 34 +++++++++++++++++++-------
 4 files changed, 82 insertions(+), 45 deletions(-)

diff --git a/README b/README
index a062b24..035fcc0 100644
--- a/README
+++ b/README
@@ -402,6 +402,14 @@ IId. Event Handling
    A subnegotiation should never be sent unless the specific option
    has been enabled through the use of the telnet negotiation
    feature.
+ 
+   ZMP SUPPORT:
+   The event->argc field is the number of ZMP parameters, including
+   the command name, that have been received.  The event->argv field
+   is an array of strings, one for each ZMP parameter.  The command
+   name will be in event->argv[0].  If the ZMP command could not be
+   parsed because it was malformed, event->argc will be 0 (zero) and
+   event->argv will be NULL.
 
  TELNET_EV_COMPRESS
    The COMPRESS event notifies the app that COMPRESS2/MCCP2
@@ -411,13 +419,6 @@ IId. Event Handling
    The event->command value will be 1 if compression has started and
    will be 0 if compression has ended.
  
- TELNET_EV_ZMP
-   The ZMP event is sent whenever a ZMP command has been received.
-   The event->argc field is the number of ZMP parameters, including
-   the command name, that have been received.  The event->argv field
-   is an array of strings, one for each ZMP parameter.  The command
-   name will be in event->argv[0].
- 
  TELNET_EV_WARNING
    The WARNING event is sent whenever something has gone wrong inside
    of libtelnet (possibly due to malformed data sent by the other
@@ -529,8 +530,15 @@ enables the client to send ZMP commands.  The client must never
 attempt to negotiate ZMP directly using telnet_negotiate().
 
 Once ZMP is enabled, any ZMP commands received will automatically be
-sent to the event handler function with the TELNET_EV_ZMP event
-code.
+sent to the event handler function with the TELNET_EV_SUBNEGOTIATION
+event code.  The command will automatically be parsed and the ZMP
+parameters will be placed in the event->argv array and the number of
+parameters will be placed in the event->argc field.
+
+NOTE: if an error occured while parsing the ZMP command because it
+was malformed, the event->argc field will be equal to 0 and the
+event->argv field will be NULL.  You should always check for this
+before attempting to access the parameter array.
 
 To send ZMP commands to the remote end, use either telnet_send_zmp()
 or telnet_send_zmpv().
diff --git a/libtelnet.c b/libtelnet.c
index 5eff06a..ba08c73 100644
--- a/libtelnet.c
+++ b/libtelnet.c
@@ -408,46 +408,53 @@ static void _negotiate(telnet_t *telnet, unsigned char telopt) {
  * must be aborted and reprocessed due to COMPRESS2 being activated
  */
 static int _subnegotiate(telnet_t *telnet) {
-	/* invoke callback */
-	_event(telnet, TELNET_EV_SUBNEGOTIATION, 0, telnet->sb_telopt,
-			telnet->buffer, telnet->buffer_pos, 0, 0);
+	const char **argv;
+	const char *c;
+	size_t i, argc;
 
+	switch (telnet->sb_telopt) {
+#ifdef HAVE_ZLIB
 	/* received COMPRESS2 begin marker, setup our zlib box and
 	 * start handling the compressed stream if it's not already.
 	 */
-#ifdef HAVE_ZLIB
-	if (telnet->sb_telopt == TELNET_TELOPT_COMPRESS2) {
-		if (_init_zlib(telnet, 0, 1) != TELNET_EOK)
-			return 0;
+	case TELNET_TELOPT_COMPRESS2:
+		if (telnet->sb_telopt == TELNET_TELOPT_COMPRESS2) {
+			if (_init_zlib(telnet, 0, 1) != TELNET_EOK)
+				return 0;
 
-		/* notify app that compression was enabled */
-		_event(telnet, TELNET_EV_COMPRESS, 1, 0, 0, 0, 0, 0);
-		return 1;
-	}
+			/* standard SB notification */
+			_event(telnet, TELNET_EV_SUBNEGOTIATION, 0, telnet->sb_telopt,
+					telnet->buffer, telnet->buffer_pos, 0, 0);
+
+			/* notify app that compression was enabled */
+			_event(telnet, TELNET_EV_COMPRESS, 1, 0, 0, 0, 0, 0);
+			return 1;
+		}
+		break;
 #endif /* HAVE_ZLIB */
-
-	/* parse ZMP args */
-	if (telnet->sb_telopt == TELNET_TELOPT_ZMP) {
-		const char **argv;
-		const char *c = telnet->buffer;
-		size_t i, argc = 0;
-
+	/* ZMP command */
+	case TELNET_TELOPT_ZMP:
 		/* make sure this is a valid ZMP buffer */
-		if (telnet->buffer_pos == 0 || telnet->buffer[telnet->buffer_pos - 1]
-				!= 0)
+		if (telnet->buffer_pos == 0 ||
+				telnet->buffer[telnet->buffer_pos - 1] != 0) {
+			_error(telnet, __LINE__, __func__, TELNET_EPROTOCOL, 0,
+					"incomplete ZMP frame");
+			_event(telnet, TELNET_EV_SUBNEGOTIATION, 0, telnet->sb_telopt,
+					telnet->buffer, telnet->buffer_pos, 0, 0);
 			return 0;
+		}
 
 		/* count arguments */
-		while (c != telnet->buffer + telnet->buffer_pos) {
-			++argc;
+		for (argc = 0, c = telnet->buffer; c != telnet->buffer +
+				telnet->buffer_pos; ++argc)
 			c += strlen(c) + 1;
-		}
 
 		/* allocate argument array, bail on error */
 		if ((argv = (const char **)malloc(sizeof(char *) * argc)) == 0) {
 			_error(telnet, __LINE__, __func__, TELNET_ENOMEM, 0,
 					"malloc() failed: %s", strerror(errno));
-			return 0;
+			_event(telnet, TELNET_EV_SUBNEGOTIATION, 0, telnet->sb_telopt,
+					telnet->buffer, telnet->buffer_pos, 0, 0);
 		}
 
 		/* populate argument array */
@@ -456,11 +463,18 @@ static int _subnegotiate(telnet_t *telnet) {
 			c += strlen(c) + 1;
 		}
 
-		/* invoke ZMP event */
-		_event(telnet, TELNET_EV_ZMP, 0, 0, 0, 0, argv, argc);
+		/* invoke event with our arguments */
+		_event(telnet, TELNET_EV_SUBNEGOTIATION, 0, telnet->sb_telopt,
+				telnet->buffer, telnet->buffer_pos, argv, argc);
 
 		/* free argument array */
 		free(argv);
+		break;
+	/* other generic subnegotiation */
+	default:
+		_event(telnet, TELNET_EV_SUBNEGOTIATION, 0, telnet->sb_telopt,
+				telnet->buffer, telnet->buffer_pos, 0, 0);
+		break;
 	}
 
 	return 0;
diff --git a/libtelnet.h b/libtelnet.h
index 54289d9..48b400f 100644
--- a/libtelnet.h
+++ b/libtelnet.h
@@ -137,7 +137,6 @@ enum telnet_event_type_t {
 	TELNET_EV_DONT,
 	TELNET_EV_SUBNEGOTIATION,
 	TELNET_EV_COMPRESS,
-	TELNET_EV_ZMP,
 	TELNET_EV_WARNING,
 	TELNET_EV_ERROR
 };
diff --git a/telnet-proxy.c b/telnet-proxy.c
index 9600c3f..7d83b4a 100644
--- a/telnet-proxy.c
+++ b/telnet-proxy.c
@@ -224,14 +224,33 @@ static void _event_handler(telnet_t *telnet, telnet_event_t *ev,
 		break;
 	/* subnegotiation */
 	case TELNET_EV_SUBNEGOTIATION:
-		printf("%s SUB %d (%s)", conn->name, (int)ev->telopt,
-				get_opt(ev->telopt));
-		if (ev->size > 0) {
-			printf(" [%zi]: ", ev->size);
-			print_buffer(ev->buffer, ev->size);
+		if (ev->telopt == TELNET_TELOPT_ZMP) {
+			if (ev->argc != 0) {
+				size_t i;
+				printf("%s ZMP [%zi params]", conn->name, ev->argc);
+				for (i = 0; i != ev->argc; ++i) {
+					printf(" \"");
+					print_buffer(ev->argv[i], strlen(ev->argv[i]));
+					printf("\"");
+				}
+				printf(COLOR_NORMAL "\n");
+			} else {
+				printf("%s ZMP (malformed!) [%zi bytes]",
+						conn->name, ev->size);
+				print_buffer(ev->buffer, ev->size);
+				printf(COLOR_NORMAL "\n");
+			}
+		} else {
+			printf("%s SUB %d (%s)", conn->name, (int)ev->telopt,
+					get_opt(ev->telopt));
+			if (ev->size > 0) {
+				printf(" [%zi bytes]: ", ev->size);
+				print_buffer(ev->buffer, ev->size);
+			}
+			printf(COLOR_NORMAL "\n");
 		}
-		printf(COLOR_NORMAL "\n");
 
+		/* forward */
 		telnet_subnegotiation(&conn->remote->telnet, ev->telopt,
 				ev->buffer, ev->size);
 		break;
@@ -240,9 +259,6 @@ static void _event_handler(telnet_t *telnet, telnet_event_t *ev,
 		printf("%s COMPRESSION %s" COLOR_NORMAL "\n", conn->name,
 				ev->command ? "ON" : "OFF");
 		break;
-	/* ZMP command (ignored in PROXY mode) */
-	case TELNET_EV_ZMP:
-		break;
 	/* warning */
 	case TELNET_EV_WARNING:
 		printf("%s WARNING: %s" COLOR_NORMAL "\n", conn->name, ev->buffer);