Merge branch 'dev-felipe' into dev-nelson

src/Notes.md

@@ -0,0 +1,4 @@
+# Notes et recherches sur le projet
+
+Telecharger la librarie OpenSSl avec 'sudo apt-get install libssl-dev'
+Utiliser 'gcc -o {exec} {fichier.c} -lssl -lcrypto' pour utiliser la librarie OpenSSL

src/README.md

@@ -0,0 +1,5 @@
+# dazibao
+
+Le but de ce projet est d’implémenter un dazibao (« journal à grandes lettres »), semblable à
+un « mur » de réseau social, mais de façon complètement distribuée. Le protocole est basé sur un
+algorithme non-fiable d’inondation.

src/hash.c

@@ -0,0 +1,60 @@
+#include "hash.h"
+
+// Hash a single data
+void hash_data(pub_data *data, unsigned char *buf) {
+	// All three fields are concatenated into a single buffer
+	int totlen = data->length + 10;
+	unsigned char concat[totlen];
+	concat_data(data, concat);
+
+	// The resulting buf is hashed and put into a buffer
+	unsigned char hash[SHA256_DIGEST_LENGTH];
+	SHA256(concat, totlen, hash);
+
+	// Put truncated hash into buf 
+	hash_trunc(hash, buf);
+}
+
+// Hash every data contained in data_list then return a network hash
+void hash_network(list *data_list, unsigned char *buf) {
+	unsigned char *concat = (unsigned char*) malloc(0);
+	unsigned char hash[SHA256_DIGEST_LENGTH];
+	int totlen = 0;
+	list *tmp = data_list;
+
+	// Hash every known data and concatenate it to buffer concat
+	while(tmp != NULL) {
+		hash_data((pub_data*) tmp->data, hash);
+		concat_hash(concat, hash, totlen);
+		totlen += 16;
+		tmp = tmp->next;
+	}
+
+	// Hash all of concat to obtain the network hash
+	SHA256(concat, totlen, hash);
+
+	// Put truncated hash into buf 
+	hash_trunc(hash, buf);
+
+	// Get rid of concat
+	free(concat);
+}
+
+// Truncate 32 octet hash to 16 octets
+void hash_trunc(unsigned char *hash32oct, unsigned char *buf) {
+	// Copy the first 16 octets from hash32oct
+	memcpy(buf, hash32oct, 16);
+}
+
+// Concat all fields of data and put them in buf
+void concat_data(pub_data *data, unsigned char *buf) {
+	memcpy(buf, &(data->id), 8);
+	memcpy(buf+8, &(data->seqno), 2);
+	memcpy(buf+10, data->data, data->length);
+}
+
+// Concat hash2 to hash1 (hash1 is modified)
+void concat_hash(unsigned char *hash1, unsigned char *hash2, size_t size) {
+	hash1 = (unsigned char*) realloc(hash1, size + 16);
+	memcpy(hash1+size, hash2, 16);
+}

src/hash.h

@@ -0,0 +1,23 @@
+#ifndef HASH_H
+#define HASH_H
+
+#include <openssl/sha.h>
+#include "node.h"
+#include "tlv.h"
+
+// Hash a single data
+void hash_data(pub_data *data, unsigned char *buf);
+
+// Hash every data contained in data_list then return a network hash
+void hash_network(list *data_list, unsigned char *buf);
+
+// Truncate 32 octet hash to 16 octets
+void hash_trunc(unsigned char *hash256bit, unsigned char *buf);
+
+// Concat all fields of data and put them in buf
+void concat_data(pub_data *data, unsigned char *buf);
+
+// Concat hash2 to hash1 (hash1 is modified)
+void concat_hash(unsigned char *hash1, unsigned char *hash2, size_t size);
+
+#endif

src/install.sh

@@ -0,0 +1 @@
+sudo apt-get install libssl-dev

src/node.c

@@ -217,20 +217,207 @@ void listen_for_packets(){
         // struct tlv_list received_tlvs;
         // if (validate_tlvs(formated_rec_datagram) < 0)
 
+<<<<<<< HEAD
         int nbr_success_tlv = work_with_tlvs(formated_rec_datagram, &req, sender);
         if (nbr_success_tlv < 0){
             perror(">> Error while treating the TLVs of the packet.");
             printf(">> Managed to deal with %i TLVs\n", -nbr_success_tlv );
         } else {
             printf(">> Done working with the TLVs of the packet, listenin for new packets.\n");
+=======
+// If the sender is not in the neighbourhood, and we have 15 neighbours, we
+// ignore the packet. Otherwise, we add him to the neighbourhood, marked as
+// temporary.
+int update_neighbours(){
+
+};
+
+// We need to make sure the TLV announces a length that will no go onto
+// another tlv, as we might end up reading bullshit.
+int validate_tlv(char *data, int pos, short packet_len){
+    char type = data[pos];
+
+    // Nothing to do in this case
+    if(type == 0)
+        return 0;
+
+    // Check that we can read a length
+    if(pos + 1 >= packet_len)
+        return -1;
+
+    unsigned char tlv_len = data[pos+1];
+
+    // Check that the tlv does not exceed the packet length
+    if(pos + length >= packet_len)
+        return -1;
+
+    // Returns the type of the tlv or -1 if something went wrong
+    switch(type) {
+        case 1:
+            return 1;
+        case 2:
+            if(tlv_len != LEN_NEIGHBOUR_REQ) return -1;
+            return 2;
+        case 3:
+            if(tlv_len != LEN_NEIGHBOUR) return -1;
+            return 3;
+        case 4:
+            if(tlv_len != LEN_NETWORK_HASH) return -1;
+            return 4;
+        case 5:
+            if(tlv_len != LEN_NETWORK_STATE_REQ) return -1;
+            return 5;
+        case 6:
+            if(tlv_len != LEN_NODE_HASH) return -1;
+            return 6;
+        case 7:
+            if(tlv_len != LEN_NODE_STATE_REQ) return -1;
+            return 7;
+        case 8:
+            if(tlv_len < MIN_LEN_NODE_STATE || tlv_len > MAX_LEN_NODE_STATE) return -1;
+            return 8;
+        case 9:
+            return 9;
+        default:
+            return -1;
+    }
+}
+
+// We then look at the differents TLVs in the packet.
+void work_with_tlvs(char *data, short packet_len){
+    int pos = 0;
+    unsigned char tlv_len;
+    tlv tmp_tlv;
+
+    while(pos < packet_len) {
+        switch(validate_tlv(data, pos, packet_len)) {
+            case 0:
+                // We received a padding tlv so it is ignored
+                pos += 1;
+                break;
+            case 1:
+                // We received a padding tlv so it is ignored
+                tlv_len = data[pos+1];
+                pos += tlv_len + 2;
+                break;
+            case 2:
+                // We received a neighbour request so a random neighbor tlv has to be sent
+                tlv_len = data[pos+1];
+                pos += tlv_len + 2;
+
+                // Send a neighbour tlv
+                neighbour_peer *random = get_random_neighbour();
+                build_neighbour(&tmp_tlv, random->ip, random->port);
+
+                // NOT FINISHED - What packet is it added to?
+                add_tlv(packet, &tmp_tlv, 3);
+                break;
+            case 3:
+                // We received a neighbour tlv so a tlv network hash is sent to that address
+            	neighbour* cur_tlv = ((neighbour*) data) + pos;
+            	struct in6_addr ip = cur_tlv->ip;
+				short port = cur_tlv->port;
+
+                tlv_len = data[pos+1];
+                pos += tlv_len + 2;
+
+                // Build network hash
+                unsigned char hash[16];
+                hash_network(neighbour_list, hash);
+                build_network_hash(&tmp_tlv, hash);
+
+                // NOT FINISHED - What packet is it added to?
+                add_tlv(packet, &tmp_tlv, 4);
+                break;
+            case 4:
+                // We reveived a network hash tlv so
+                tlv_len = data[pos+1];
+                pos += tlv_len +2;
+
+                // NOT FINISHED - Where is network_hash?
+                build_neighbour(&tmp_tlv, network_hash);
+                // NOT FINISHED - What packet is it added to?
+                add_tlv(packet, &tmp_tlv, 4);
+                break;
+            case 5:
+                // We received a network state request tlv so a series of tlv node hash have to be sent for each data known
+                pos += 2;
+
+                // NOT FINISHED - for each known data
+                list *tmp_list = data_list;
+                pub_data *tmp_data;
+
+                while(tmp_list != NULL) {
+                	tmp_data = (pub_data*) tmp_list->data;
+                	build_node_hash(&tmp_tlv, tmp_data->id, tmp_data->seqno);
+                }
+
+                break;
+            case 6:
+                // We received a node hash tlv
+                break;
+            case 7:
+                // We received a node state request tlv
+                break;
+            case 8:
+                // We received a node state tlv
+                break;
+            case 9:
+                // We received a warning tlv so it's message is printed
+                break;
+            default:
+                return ;
         }
     }
 }
 
-int main(int argc, char const *argv[]) {
-    int continue = 1;
 
-    while(continue != 0){
+
+void work_with_tlvs(struct tlvs_list receivied_tlvs){
+
+    // For every TLV,
+        // We make sure the TLV is legal.
+        if(!validate_tlvs(tlv)){
+            perror(">> Invalid TLV receivied, it will be ignored.");
+>>>>>>> dev-felipe
+        }
+    }
+}
+
+// Get list length
+int len_list(list *l) {
+	int len = 0;
+	list *tmp = l;
+
+	while(tmp != NULL) {
+		tmp = tmp->next;
+		len++;
+	}
+
+	return len;
+}
+
+// Get a random neighbour
+neighbour_peer *get_random_neighbour() {
+	// Get a random number
+    time_t t;
+    srand((unsigned) time(&t));
+    int n = rand() % len_list(neighbour_list);
+
+    // Get nth neighbour
+    list *tmp = neighbour_list;
+
+    for(int i=0; i<n; i++) {
+    	tmp = tmp->next;
+    }
+
+    return (neighbour_peer*) tmp->data;
+}
+
+int main(int argc, const char *argv[]) {
+    int cont = 1;
+
+    while(cont){
 
         // We create the neighbourhood table
         neighbour_peer neighbour_list[NEIGHBOUR_MAX];

src/node.h

@@ -3,9 +3,16 @@
 #ifndef NODE_H
 #define NODE_H
 
+#include <stdlib.h>
+#include <time.h>
+#include <stdio.h>
+#include <sys/types.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
+#include <string.h>
+
 #include "tlv.h"
+#include "hash.h"
 
 // On which port do we listen to
 #define LISTEN_PORT 1212
@@ -36,11 +43,22 @@ typedef struct neighbour_peer {
  * Di : the data of the message 192 bytes
 */
 
-typedef struct message {
-    long node_id_publisher;
+typedef struct pub_data {
+	unsigned char length;
+    long id;
     short seqno;
     char *data;
-} message;
+} pub_data;
+
+// General list
+typedef struct list {
+	void *data;
+	void *next;
+} list;
+
+// Static variables
+static list *data_list;
+static list *neighbour_list;
 
 // TODO
 
@@ -55,6 +73,10 @@ int update_neighbours();
 
 int work_with_tlvs(struct packet received_packet, char * data_from_packet[], struct sockaddr_in6 sender);
 
+void add_tlv(packet *packet, tlv *tlv, char type);
+
+int send_packet(struct tlv_list tlvs_to_send, );
+
 // threaded functions
 
 void t_ask_for_more_peers();
@@ -64,8 +86,8 @@ void t_update_neighbours();
 void t_get_network_state();
 
 // Helper functions
-char * hash();
+int len_list(list *l);
 
-short * get_seq_no(short s, int n);
+neighbour_peer *get_random_neighbour();
 
 #endif

src/parser.c

@@ -22,8 +22,8 @@ cmd_token parse_cmd() {
 			token.type = NETWORK_STATE_REQ;
 		else if(strcmp("node state", arg) == 0)
 			token.type = NODE_STATE_REQ;
-	} else if(strcmp("send", cmd) == 0) {
-		token.type = SEND;
+	} else if(strcmp("post", cmd) == 0) {
+		token.type = POST;
 		//arg[192] = 0;
 		strcpy(token.arg, arg);
 	}

src/parser.h

@@ -5,7 +5,7 @@
 #define PARSER_H
 
 typedef enum cmd_type {
-	NEIGHBOUR_REQ, NETWORK_STATE_REQ, NODE_STATE_REQ, SEND, ERROR
+	NEIGHBOUR_REQ, NETWORK_STATE_REQ, NODE_STATE_REQ, POST, ERROR
 } cmd_type;
 
 typedef struct cmd_token {
@@ -16,4 +16,4 @@ typedef struct cmd_token {
 // retourne le type de commande à exécuter
 cmd_token parse_cmd();
 
-#endif
+#endif

src/tlv.c

@@ -12,11 +12,11 @@ int build_tlv(tlv *tlv, cmd_token token) {
 		case NODE_STATE_REQ:
 			// a remplir
 			break;
-		case SEND:
+		case POST:
 			// a remplir
 			break;
 		case ERROR:
-			printf("Wrong format, use 'req {neighbour | network state | node state}' or 'send {message}'");
+			printf("Wrong format, use 'req {neighbour | network state | node state}' or 'post {message}'");
 			break;
 	}
 }

src/tlv.h

@@ -1,10 +1,20 @@
+#ifndef TLV_H
+#define TLV_H
+
 #include <sys/socket.h>
 #include <netinet/in.h>
 #include <stdlib.h>
 #include "parser.h"
+#include "hash.h"
 
-#ifndef TLV_H
-#define TLV_H
+#define LEN_NEIGHBOUR_REQ 0
+#define LEN_NEIGHBOUR 18
+#define LEN_NETWORK_HASH 16
+#define LEN_NETWORK_STATE_REQ 0
+#define LEN_NODE_HASH 26
+#define LEN_NODE_STATE_REQ 8
+#define MIN_LEN_NODE_STATE 26
+#define MAX_LEN_NODE_STATE 218
 
 // 8 octets min (struct pointer 4 octets), 1024 octets max
 typedef struct packet {
@@ -23,7 +33,7 @@ typedef struct pad1 {
 typedef struct padn {
 	unsigned char type;
 	unsigned char length;
-	char *mbz;
+	char mbz[256];
 } padn;
 
 // 2 octets
@@ -76,14 +86,14 @@ typedef struct node_state {
 	long node_id;
 	short seqno;
 	char node_hash[16];
-	char *data;
+	char data[192];
 } node_state;
 
 // 2 octets min, 258 ocets max (unsigned char 0 -> 255)
 typedef struct warning {
 	unsigned char type;
 	unsigned char length;
-	char *message;
+	char message[256];
 } warning;
 
 typedef union tlv {
@@ -99,20 +109,14 @@ typedef union tlv {
 	warning *warning;
 } tlv;
 
-typedef struct tlv_list {
-		union tlv one_tlv;
-		struct tlv_list * next;
-} tlv_list;
-
-
-// creer un tlv
+// build tlv from token
 int build_tlv(tlv *tlv, cmd_token token);
 
-// creer un tlv specifique
+// build specific tlv
 int build_pad1(tlv *tlv);
 int build_padn(tlv *tlv, size_t len);
 int build_neighbour_req(tlv *tlv);
-int build_neighbour(tlv *tlv, struct in6_addr ip, short seqno);
+int build_neighbour(tlv *tlv, struct in6_addr ip, short port);
 int build_network_hash(tlv *tlv, char *network_hash);
 int build_network_state_req(tlv *tlv);
 int build_node_hash(tlv *tlv, long node_id, short seqno, char *node_hash);