diff -r 8654d04cb094 -r 766c92a94b04 libpurple/protocols/mxit/cipher.c
--- a/libpurple/protocols/mxit/cipher.c	Thu Aug 11 15:01:34 2011 +0000
+++ b/libpurple/protocols/mxit/cipher.c	Tue Aug 16 05:38:01 2011 +0000
@@ -1,7 +1,7 @@
 /*
  *					MXit Protocol libPurple Plugin
  *
- *					-- user password encryption --
+ *						-- encryption --
  *
  *				Pieter Loubser	<libpurple@mxit.com>
  *
@@ -31,31 +31,69 @@
 #include	"aes.h"
 
 
-/* password encryption */
+/* encryption */
 #define		INITIAL_KEY		"6170383452343567"
 #define		SECRET_HEADER	"<mxit/>"
 #define		ENCRYPT_HEADER	"<mxitencrypted ver=\"5.2\"/>"
 
 
 /*------------------------------------------------------------------------
- * Pad the secret data using ISO10126 Padding.
+ * Add ISO10126 Padding to the data.
  *
- *  @param secret	The data to pad (caller must ensure buffer has enough space for padding)
- *  @return			The total number of 128-bit blocks used
+ *  @param data		The data to pad.
  */
-static int pad_secret_data( char* secret )
+static void padding_add( GString* data )
+{
+	unsigned int blocks = ( data->len / 16 ) + 1;
+	unsigned int padding = ( blocks * 16 ) - data->len;
+
+	g_string_set_size( data, blocks * 16 );
+	data->str[data->len - 1] = padding;
+}
+
+
+/*------------------------------------------------------------------------
+ * Remove ISO10126 Padding from the data.
+ *
+ *  @param data		The data from which to remove padding.
+ */
+static void padding_remove( GString* data )
 {
-	int		blocks	= 0;
-	int		passlen;
-	int		padding;
+	unsigned int padding;
+
+	if ( data->len == 0 )
+		return;
+
+	padding = data->str[data->len - 1];
+	g_string_truncate( data, data->len - padding );
+}
+
 
-	passlen = strlen( secret );
-	blocks = ( passlen / 16 ) + 1;
-	padding = ( blocks * 16 ) - passlen;
-	secret[passlen] = 0x50;
-	secret[(blocks * 16) - 1] = padding;
+/*------------------------------------------------------------------------
+ * Generate the Transport-Layer crypto key.
+ *  (Note: this function is not-thread safe)
+ *
+ *  @param session	The MXit Session object
+ *	@return			The transport-layer crypto key.
+ */
+static char* transport_layer_key( struct MXitSession* session )
+{
+	static char	key[16 + 1];
+	int			passlen			= strlen( session->acc->password );
 
-	return blocks;
+	/* initialize with initial key */
+	g_strlcpy( key, INITIAL_KEY, sizeof( key ) );
+
+	/* client key (8 bytes) */
+	memcpy( key, session->clientkey, strlen( session->clientkey ) );
+
+	/* add last 8 characters of the PIN (no padding if less characters) */
+	if ( passlen <= 8 )
+		memcpy( key + 8, session->acc->password, passlen );
+	else
+		memcpy( key + 8, session->acc->password + ( passlen - 8 ), 8 );
+
+	return key;
 }
 
 
@@ -68,21 +106,16 @@
  */
 char* mxit_encrypt_password( struct MXitSession* session )
 {
-	char		key[64];
+	char		key[16 + 1];
 	char		exkey[512];
-	char		pass[64];
+	GString*	pass			= NULL;
 	char		encrypted[64];
 	char*		base64;
-	int			blocks;
-	int			size;
 	int			i;
 
 	purple_debug_info( MXIT_PLUGIN_ID, "mxit_encrypt_password\n" );
 
 	memset( encrypted, 0x00, sizeof( encrypted ) );
-	memset( exkey, 0x00, sizeof( exkey ) );
-	memset( pass, 0x58, sizeof( pass ) );
-	pass[sizeof( pass ) - 1] = '\0';
 
 	/* build the custom AES encryption key */
 	g_strlcpy( key, INITIAL_KEY, sizeof( key ) );
@@ -102,7 +135,9 @@
 		Encrypt( (unsigned char*) pass + i, (unsigned char*) exkey, (unsigned char*) encrypted + i );
 
 	/* now base64 encode the encrypted password */
-	base64 = purple_base64_encode( (unsigned char*) encrypted, size );
+	base64 = purple_base64_encode( (unsigned char*) encrypted, pass->len );
+
+	g_string_free( pass, TRUE );
 
 	return base64;
 }