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Change-Id: I6a4444e3c193dae437cd7929f4c39aba7b749efa
diff --git a/extensions/rt_ereg/rtereg.c b/extensions/rt_ereg/rtereg.c
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+++ b/extensions/rt_ereg/rtereg.c
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+/*********************************************************************************************************
+* 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.								 *
+*********************************************************************************************************/
+
+/* 
+ * This extension allows to perform some pattern-matching on an AVP
+ * and send the message to a server accordingly.
+ * See rt_ereg.conf.sample file for the format of the configuration file.
+ */
+
+#include "rtereg.h"
+
+/* The configuration structure */
+struct rtereg_conf rtereg_conf;
+
+#ifndef HAVE_REG_STARTEND
+static char * buf = NULL;
+static size_t bufsz;
+static pthread_mutex_t mtx = PTHREAD_MUTEX_INITIALIZER;
+#endif /* HAVE_REG_STARTEND */
+
+static int proceed(char * value, size_t len, struct fd_list * candidates)
+{
+	int i;
+	
+	for (i = 0; i < rtereg_conf.rules_nb; i++) {
+		/* Does this pattern match the value? */
+		struct rtereg_rule * r = &rtereg_conf.rules[i];
+		int err = 0;
+		struct fd_list * c;
+		
+		TRACE_DEBUG(ANNOYING, "Attempt pattern matching of '%.*s' with rule '%s'", (int)len, value, r->pattern);
+		
+		#ifdef HAVE_REG_STARTEND
+		{
+			regmatch_t pmatch[1];
+			memset(pmatch, 0, sizeof(pmatch));
+			pmatch[0].rm_so = 0;
+			pmatch[0].rm_eo = len;
+			err = regexec(&r->preg, value, 0, pmatch, REG_STARTEND);
+		}
+		#else /* HAVE_REG_STARTEND */
+		{
+			/* We have a 0-terminated string */
+			err = regexec(&r->preg, value, 0, NULL, 0);
+		}
+		#endif /* HAVE_REG_STARTEND */
+		
+		if (err == REG_NOMATCH)
+			continue;
+			
+		if (err != 0) {
+			char * errstr;
+			size_t bl;
+
+			/* Error while compiling the regex */
+			TRACE_DEBUG(INFO, "Error while executing the regular expression '%s':", r->pattern);
+
+			/* Get the error message size */
+			bl = regerror(err, &r->preg, NULL, 0);
+
+			/* Alloc the buffer for error message */
+			CHECK_MALLOC( errstr = malloc(bl) );
+
+			/* Get the error message content */
+			regerror(err, &r->preg, errstr, bl);
+			TRACE_DEBUG(INFO, "\t%s", errstr);
+
+			/* Free the buffer, return the error */
+			free(errstr);
+			
+			return (err == REG_ESPACE) ? ENOMEM : EINVAL;
+		}
+		
+		/* From this point, the expression matched the AVP value */
+		TRACE_DEBUG(FULL, "[rt_ereg] Match: '%s' to value '%.*s' => '%s' += %d",
+					r->pattern,
+					(int)len,
+					value,
+					r->server,
+					r->score);
+		
+		for (c = candidates->next; c != candidates; c = c->next) {
+			struct rtd_candidate * cand = (struct rtd_candidate *)c;
+
+			if (strcmp(r->server, cand->diamid) == 0) {
+				cand->score += r->score;
+				break;
+			}
+		}
+	};
+	
+	return 0;
+}
+
+/* The callback called on new messages */
+static int rtereg_out(void * cbdata, struct msg ** pmsg, struct fd_list * candidates)
+{
+	struct msg * msg = *pmsg;
+	struct avp * avp = NULL;
+	
+	TRACE_ENTRY("%p %p %p", cbdata, msg, candidates);
+	
+	CHECK_PARAMS(msg && candidates);
+	
+	/* Check if it is worth processing the message */
+	if (FD_IS_LIST_EMPTY(candidates)) {
+		return 0;
+	}
+	
+	/* Now search the AVP in the message */
+	CHECK_FCT( fd_msg_search_avp ( msg, rtereg_conf.avp, &avp ) );
+	if (avp != NULL) {
+		struct avp_hdr * ahdr = NULL;
+		CHECK_FCT( fd_msg_avp_hdr ( avp, &ahdr ) );
+		if (ahdr->avp_value != NULL) {
+#ifndef HAVE_REG_STARTEND
+			int ret;
+		
+			/* Lock the buffer */
+			CHECK_POSIX( pthread_mutex_lock(&mtx) );
+			
+			/* Augment the buffer if needed */
+			if (ahdr->avp_value->os.len >= bufsz) {
+				CHECK_MALLOC_DO( buf = realloc(buf, ahdr->avp_value->os.len + 1), 
+					{ pthread_mutex_unlock(&mtx); return ENOMEM; } );
+			}
+			
+			/* Copy the AVP value */
+			memcpy(buf, ahdr->avp_value->os.data, ahdr->avp_value->os.len);
+			buf[ahdr->avp_value->os.len] = '\0';
+			
+			/* Now apply the rules */
+			ret = proceed(buf, ahdr->avp_value->os.len, candidates);
+			
+			CHECK_POSIX(pthread_mutex_unlock(&mtx));
+			
+			CHECK_FCT(ret);
+#else /* HAVE_REG_STARTEND */
+			CHECK_FCT( proceed((char *) ahdr->avp_value->os.data, ahdr->avp_value->os.len, candidates) );
+#endif /* HAVE_REG_STARTEND */
+		}
+	}
+	
+	return 0;
+}
+
+/* handler */
+static struct fd_rt_out_hdl * rtereg_hdl = NULL;
+
+/* entry point */
+static int rtereg_entry(char * conffile)
+{
+	TRACE_ENTRY("%p", conffile);
+	
+	/* Initialize the configuration */
+	memset(&rtereg_conf, 0, sizeof(rtereg_conf));
+	
+	/* Parse the configuration file */
+	CHECK_FCT( rtereg_conf_handle(conffile) );
+	
+	/* Register the callback */
+	CHECK_FCT( fd_rt_out_register( rtereg_out, NULL, 1, &rtereg_hdl ) );
+	
+	/* We're done */
+	return 0;
+}
+
+/* Unload */
+void fd_ext_fini(void)
+{
+	int i;
+	TRACE_ENTRY();
+	
+	/* Unregister the cb */
+	CHECK_FCT_DO( fd_rt_out_unregister ( rtereg_hdl, NULL ), /* continue */ );
+	
+	/* Destroy the data */
+	if (rtereg_conf.rules) 
+		for (i = 0; i < rtereg_conf.rules_nb; i++) {
+			free(rtereg_conf.rules[i].pattern);
+			free(rtereg_conf.rules[i].server);
+			regfree(&rtereg_conf.rules[i].preg);
+		}
+	free(rtereg_conf.rules);
+#ifndef HAVE_REG_STARTEND
+	free(buf);
+#endif /* HAVE_REG_STARTEND */
+	
+	/* Done */
+	return ;
+}
+
+EXTENSION_ENTRY("rt_ereg", rtereg_entry);