Packet Signing & Key Verification Stage: Start
diff --git a/nlsr_km_util.c b/nlsr_km_util.c
new file mode 100644
index 0000000..ee55252
--- /dev/null
+++ b/nlsr_km_util.c
@@ -0,0 +1,169 @@
+#include<stdio.h>
+#include<string.h>
+#include<stdlib.h>
+#include <unistd.h>
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+
+#include <ccn/ccn.h>
+#include <ccn/uri.h>
+#include <ccn/keystore.h>
+#include <ccn/signing.h>
+#include <ccn/schedule.h>
+#include <ccn/hashtb.h>
+
+
+#include "nlsr.h"
+#include "nlsr_km_util.h"
+#include "nlsr_km.h"
+
+int
+appendLifetime(struct ccn_charbuf *cb, int lifetime) 
+{
+	unsigned char buf[sizeof(int32_t)];
+	int32_t dreck = lifetime << 12;
+	int pos = sizeof(int32_t);
+	int res = 0;
+	while (dreck > 0 && pos > 0) 
+	{
+		pos--;
+		buf[pos] = dreck & 255;
+		dreck = dreck >> 8;
+	}
+	res |= ccnb_append_tagged_blob(cb, CCN_DTAG_InterestLifetime, buf+pos, 
+															sizeof(buf)-pos);
+	return res;
+}
+
+int
+contain_key_name(const unsigned char *ccnb, struct ccn_parsed_ContentObject *pco) 
+{
+	if (pco->offset[CCN_PCO_B_KeyLocator] == pco->offset[CCN_PCO_E_KeyLocator])
+		return -1;
+
+	struct ccn_buf_decoder decoder;
+	struct ccn_buf_decoder *d;
+	d = ccn_buf_decoder_start(&decoder, ccnb + 
+		pco->offset[CCN_PCO_B_Key_Certificate_KeyName], 
+		pco->offset[CCN_PCO_E_Key_Certificate_KeyName] - 
+		pco->offset[CCN_PCO_B_Key_Certificate_KeyName]);
+	if (ccn_buf_match_dtag(d, CCN_DTAG_KeyName))
+		return 1;
+
+	return -1;
+}
+
+struct ccn_charbuf *
+get_key_name(const unsigned char *ccnb, struct ccn_parsed_ContentObject *pco) 
+{
+	struct ccn_charbuf *key_name = ccn_charbuf_create();
+	ccn_charbuf_append(key_name, ccnb + pco->offset[CCN_PCO_B_KeyName_Name], 
+	pco->offset[CCN_PCO_E_KeyName_Name] - pco->offset[CCN_PCO_B_KeyName_Name]);
+
+	return key_name;
+}
+
+int
+check_for_name_component_in_name(const struct ccn_charbuf *name, 
+								const struct ccn_indexbuf *indx,
+								const char *component){
+	
+	int res,i;
+	int result_position=0;
+	int name_comps=(int)indx->n;
+
+	for(i=0;i<name_comps;i++){
+		res=ccn_name_comp_strcmp(name->buf,indx,i,component);
+		if( res == 0){
+			
+				result_position=i;
+				break;
+		}	
+	}
+
+	return result_position;
+}
+
+
+int
+check_for_tag_component_in_name(const struct ccn_charbuf *name, 
+								const struct ccn_indexbuf *indx,
+								const char *component){
+	
+	int res,i;
+	int result_position=0;
+	int name_comps=(int)indx->n;
+
+	for(i=0;i<name_comps;i++){
+		const unsigned char *comp_ptr;
+		size_t comp_size;
+		res=ccn_name_comp_get(name->buf, indx,i,&comp_ptr, &comp_size);
+		if( res == 0){
+			if ( strstr((char *)comp_ptr,component) != NULL ){
+				result_position=i;
+				break;
+			}
+		}	
+	}
+
+	return result_position;
+}
+
+enum key_type
+get_key_type_from_key_name(struct ccn_charbuf *keyname)
+{
+	printf("get_key_type_from_key_name called\n");
+
+	int res;
+	int return_key=UNKNOWN_KEY;	
+
+	struct ccn_indexbuf *indx=ccn_indexbuf_create();
+	if ( indx == NULL ){
+		printf("Error in creating index for key name \n");
+		return UNKNOWN_KEY;
+	}
+
+	res=ccn_name_split(keyname,indx);
+	if ( res < 0 ){
+		printf("Error in parsing key name \n");
+		ccn_indexbuf_destroy(&indx);
+		return UNKNOWN_KEY;
+	}
+	else if ( res == 3){
+		int chk_ndn=check_for_name_component_in_name(keyname,indx,"ndn");
+		int chk_key=check_for_name_component_in_name(keyname,indx,"keys");
+		if ( chk_ndn == 0 && chk_key == 1)
+			return_key=ROOT_KEY;
+	}
+	else{
+		int check_op,check_rt;
+		check_op=check_for_tag_component_in_name(keyname,indx,
+													 "O.N.Start");
+		check_rt=check_for_tag_component_in_name(keyname,indx,
+													 "R.N.Start");
+		if ( check_op > 0){
+			return_key=OPERATOR_KEY;
+		}
+		else if(check_rt >0){
+			int check_nlsr;
+			check_nlsr=check_for_name_component_in_name(keyname,indx,
+													 "nlsr");
+			if ( check_rt > 0 ){
+				if ( check_nlsr > 0){
+					return_key=NLSR_KEY;
+				}
+				else{
+					return_key=ROUTING_KEY;
+				}
+			}
+		}
+		else if ( check_rt == 0 && check_op == 0 && res > 3){
+			return_key=SITE_KEY;
+		}
+	}
+
+	ccn_indexbuf_destroy(&indx);
+	return return_key;
+}