diff --git a/extensions/app_radgw/rgw_conf.l b/extensions/app_radgw/rgw_conf.l
new file mode 100644
index 0000000..8afd779
--- /dev/null
+++ b/extensions/app_radgw/rgw_conf.l
@@ -0,0 +1,277 @@
+/*********************************************************************************************************
+* Software License Agreement (BSD License)                                                               *
+* Author: Sebastien Decugis <sdecugis@freediameter.net>							 *
+*													 *
+* Copyright (c) 2013, WIDE Project and NICT								 *
+* All rights reserved.											 *
+* 													 *
+* Redistribution and use of this software in source and binary forms, with or without modification, are  *
+* permitted provided that the following conditions are met:						 *
+* 													 *
+* * Redistributions of source code must retain the above 						 *
+*   copyright notice, this list of conditions and the 							 *
+*   following disclaimer.										 *
+*    													 *
+* * Redistributions in binary form must reproduce the above 						 *
+*   copyright notice, this list of conditions and the 							 *
+*   following disclaimer in the documentation and/or other						 *
+*   materials provided with the distribution.								 *
+* 													 *
+* * Neither the name of the WIDE Project or NICT nor the 						 *
+*   names of its contributors may be used to endorse or 						 *
+*   promote products derived from this software without 						 *
+*   specific prior written permission of WIDE Project and 						 *
+*   NICT.												 *
+* 													 *
+* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED *
+* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A *
+* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR *
+* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 	 *
+* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 	 *
+* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR *
+* TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF   *
+* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.								 *
+*********************************************************************************************************/
+/* Lex configuration parser for radius_gw extension.
+ *
+ */
+
+%{
+#include "rgw.h"
+#include "rgw_conf.tab.h"
+
+/* Update the column information */
+#define YY_USER_ACTION { 						\
+	yylloc->first_column = yylloc->last_column + 1; 		\
+	yylloc->last_column = yylloc->first_column + yyleng - 1;	\
+}
+
+/* %option noinput ? */
+#define YY_NO_INPUT
+%}
+
+%option bison-bridge bison-locations
+%option noyywrap
+%option nounput
+
+/* Use the following start condition to parse an URI */
+%x	IN_PLG
+%x	IN_CLI1
+%x	IN_CLI2
+%x	EXPECT_IP4
+%x	EXPECT_IP6
+%x	EXPECT_DECINT
+
+/* Quoted string. Multilines do not match. */
+qstring		\"[^\"\n]*\"
+
+/* Used to match IP, IP6, and port */
+IP4		[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}
+IP6		[[:xdigit:]]*:[[:xdigit:]]*:[[:xdigit:].:]*
+BR_PORT		[[][0-9]+[]]
+
+
+%%
+
+	/* All sections */
+<*>\n			{ 
+				/* Update the line count */
+				yylloc->first_line++; 
+				yylloc->last_line++; 
+				yylloc->last_column=0; 
+			} 
+
+<*>([[:space:]]{-}[\n])+	; /* Eat all spaces, not new lines */
+<*>#.*$			; /* Eat all comments */
+
+<*>{qstring}		{
+				/* First copy the string without the quotes for use in the yacc parser */
+				yylval->string = strdup(yytext+1);
+				if (yylval->string == NULL) {
+					fd_log_debug("Unable to allocate memory: %s", strerror(errno));
+					return LEX_ERROR; /* trig an error in yacc parser */
+				}
+
+				yylval->string[yyleng-2] = '\0';
+				
+				/* the yacc parser will check the string is valid */
+				return QSTRING;
+			}
+
+
+	/* Extension section */			
+(?i:"RGWX")		{ BEGIN(IN_PLG); return PLG_PREFIX; 		}
+
+<IN_PLG>(?i:"auth")	{ return AUTH; }
+<IN_PLG>(?i:"acct")	{ return ACCT; }
+
+<IN_PLG,IN_CLI2>[[:xdigit:]]+	{
+				/* Convert this to an integer value */
+				int ret = sscanf(yytext, "%x", &yylval->integer);
+				if (ret != 1) {
+					/* No matching: an error occurred */
+					fd_log_debug("Unable to convert the value '%s' to a valid number: %s", yytext, strerror(errno));
+					return LEX_ERROR; /* trig an error in yacc parser */
+					/* Maybe we could REJECT instead of failing here? */
+				}
+				return INTEGER;
+			}
+
+<IN_PLG>[:]		{ return yytext[0]; }
+
+
+	/* Client section */
+(?i:"nas"|"cli")	{ BEGIN(IN_CLI1); yylval->integer=RGW_CLI_NAS; return NAS_OR_PXY; 		}
+(?i:"pxy")		{ BEGIN(IN_CLI1); yylval->integer=RGW_CLI_PXY; return NAS_OR_PXY; 		}
+
+	/* Match an IP (4 or 6) and optional port */
+<IN_CLI1>({IP4}|{IP6}){BR_PORT}?	{
+				char * work;
+				char * port;
+				unsigned short p = 0;
+				
+				work = strdup(yytext);
+				if ( work == NULL ) {
+					fd_log_debug("Unable to allocate memory: %s", strerror(errno));
+					return LEX_ERROR; /* trig an error in yacc parser */
+				}
+				
+				if ((port = strchr(work, '[')) != NULL) {
+					*port = '\0';
+					port++;
+					if (sscanf(port, "%hu]", &p) != 1) {
+						fd_log_debug("'%s' is not a valid port: %s", port, strerror(errno));
+						free(work);
+						return LEX_ERROR; /* trig an error in yacc parser */
+					}
+				}
+				
+				/* Do we have an IP or IPv6? Let's check if we have ':' char somewhere in the beginning */
+				if (memchr(work, ':', 5) != NULL) {
+					struct sockaddr_in6 * sin6 = NULL;
+				
+					sin6 = malloc(sizeof(struct sockaddr_in6));
+					if (sin6 == NULL) {
+						fd_log_debug("Unable to allocate memory: %s", strerror(errno));
+						free(work);
+						return LEX_ERROR; /* trig an error in yacc parser */
+					}
+					
+					memset(sin6, 0, sizeof(struct sockaddr_in6));
+					sin6->sin6_family = AF_INET6;
+					if (inet_pton(AF_INET6, work, &sin6->sin6_addr) != 1) {
+						fd_log_debug("'%s' is not a valid IPv6 address: %s", work, strerror(errno));
+						free(work);
+						free(sin6);
+						return LEX_ERROR; /* trig an error in yacc parser */
+					}
+					sin6->sin6_port = htons(p);
+					yylval->ss = (struct sockaddr *)sin6;
+				} else {
+					struct sockaddr_in * sin = NULL;
+				
+					sin = malloc(sizeof(struct sockaddr_in));
+					if (sin == NULL) {
+						fd_log_debug("Unable to allocate memory: %s", strerror(errno));
+						free(work);
+						return LEX_ERROR; /* trig an error in yacc parser */
+					}
+					
+					memset(sin, 0, sizeof(struct sockaddr_in));
+					sin->sin_family = AF_INET;
+					if (inet_pton(AF_INET, work, &sin->sin_addr) != 1) {
+						fd_log_debug("'%s' is not a valid IP address: %s", work, strerror(errno));
+						free(work);
+						free(sin);
+						return LEX_ERROR; /* trig an error in yacc parser */
+					}
+					
+					sin->sin_port = htons(p);
+					yylval->ss = (struct sockaddr *)sin;
+				}
+				free(work);
+				return IP;
+			}
+
+
+<IN_CLI1>"/"		{ BEGIN(IN_CLI2); return '/';	 		}
+
+
+	/* Servers section */
+(?i:"auth_server_enable")	{ BEGIN(EXPECT_DECINT); return AUTH_ENABLE; 	}
+(?i:"auth_server_port")		{ BEGIN(EXPECT_DECINT); return AUTH_PORT; 	}
+(?i:"auth_server_ip4")		{ BEGIN(EXPECT_IP4); return AUTH_IP4; 		}
+(?i:"auth_server_ip6")		{ BEGIN(EXPECT_IP6); return AUTH_IP6; 		}
+(?i:"acct_server_enable")	{ BEGIN(EXPECT_DECINT); return ACCT_ENABLE; 	}
+(?i:"acct_server_port")		{ BEGIN(EXPECT_DECINT); return ACCT_PORT; 	}
+(?i:"acct_server_ip4")		{ BEGIN(EXPECT_IP4); return ACCT_IP4; 		}
+(?i:"acct_server_ip6")		{ BEGIN(EXPECT_IP6); return ACCT_IP6; 		}
+
+<EXPECT_DECINT>[[:digit:]]+	{
+					/* Match an integer (not hexa) */
+					int ret = sscanf(yytext, "%d", &yylval->integer);
+					if (ret != 1) {
+						/* No matching: an error occurred */
+						fd_log_debug("Unable to convert the value '%s' to a valid number: %s", yytext, strerror(errno));
+						return LEX_ERROR; /* trig an error in yacc parser */
+						/* Maybe we could REJECT instead of failing here? */
+					}
+					return INTEGER;
+				}
+
+<EXPECT_IP4,EXPECT_IP6>(?i:"disable")	{ return DISABLED; 				}
+				
+<EXPECT_IP4>{IP4}		{
+					struct sockaddr_in * sin = NULL;
+				
+					sin = malloc(sizeof(struct sockaddr_in));
+					if (sin == NULL) {
+						fd_log_debug("Unable to allocate memory: %s", strerror(errno));
+						return LEX_ERROR; /* trig an error in yacc parser */
+					}
+					
+					memset(sin, 0, sizeof(struct sockaddr_in));
+					sin->sin_family = AF_INET;
+					if (inet_pton(AF_INET, yytext, &sin->sin_addr) != 1) {
+						fd_log_debug("'%s' is not a valid IP address: %s", yytext, strerror(errno));
+						free(sin);
+						return LEX_ERROR; /* trig an error in yacc parser */
+					}
+					yylval->ss = (struct sockaddr *)sin;
+					return IP;
+				}
+
+<EXPECT_IP6>{IP6}		{
+					struct sockaddr_in6 * sin6 = NULL;
+				
+					sin6 = malloc(sizeof(struct sockaddr_in6));
+					if (sin6 == NULL) {
+						fd_log_debug("Unable to allocate memory: %s", strerror(errno));
+						return LEX_ERROR; /* trig an error in yacc parser */
+					}
+					
+					memset(sin6, 0, sizeof(struct sockaddr_in6));
+					sin6->sin6_family = AF_INET6;
+					if (inet_pton(AF_INET6, yytext, &sin6->sin6_addr) != 1) {
+						fd_log_debug("'%s' is not a valid IPv6 address: %s", yytext, strerror(errno));
+						free(sin6);
+						return LEX_ERROR; /* trig an error in yacc parser */
+					}
+					yylval->ss = (struct sockaddr *)sin6;
+					return IP;
+				}
+
+	
+	/* Valid single characters for yyparse in all contexts */
+<*>[=]			{ return yytext[0]; }
+<*>[;]			{ BEGIN(INITIAL); return yytext[0]; }
+
+	/* Unrecognized token */
+<*>[[:alnum:]]+		|	/* This rule is only useful to print a complete token in error messages */
+	/* Unrecognized character */
+<*>.			{ 
+				fd_log_debug("Unrecognized text on line %d col %d: '%s'.", yylloc->first_line, yylloc->first_column, yytext);
+			 	return LEX_ERROR; 
+			}
+
+%%