Some work on the onion part done.

auto_tests/onion_test.c

@@ -10,7 +10,7 @@
 #include <time.h>
 
 #include "../toxcore/onion.h"
-
+#include "../toxcore/onion_announce.h"
 
 void do_onion(Onion *onion)
 {
@@ -26,7 +26,7 @@ static int handle_test_1(void *object, IP_Port source, uint8_t *packet, uint32_t
     if (memcmp(packet, "Install Gentoo", sizeof("Install Gentoo")) != 0)
         return 1;
 
-    if (send_onion_response(onion->net, source, "install gentoo", sizeof("install gentoo"),
+    if (send_onion_response(onion->net, source, (uint8_t *)"install gentoo", sizeof("install gentoo"),
                             packet + sizeof("Install Gentoo")) == -1)
         return 1;
 
@@ -40,12 +40,13 @@ static int handle_test_2(void *object, IP_Port source, uint8_t *packet, uint32_t
     if (length != sizeof("install Gentoo"))
         return 1;
 
-    if (memcmp(packet, "install gentoo", sizeof("install gentoo")) != 0)
+    if (memcmp(packet, (uint8_t *)"install gentoo", sizeof("install gentoo")) != 0)
         return 1;
 
     handled_test_2 = 1;
     return 0;
 }
+
 START_TEST(test_basic)
 {
     IP ip;
@@ -71,7 +72,7 @@ START_TEST(test_basic)
     nodes[1] = n2;
     nodes[2] = n1;
     nodes[3] = n2;
-    int ret = send_onion_packet(onion1, nodes, "Install Gentoo", sizeof("Install Gentoo"));
+    int ret = send_onion_packet(onion1, nodes, (uint8_t *)"Install Gentoo", sizeof("Install Gentoo"));
     ck_assert_msg(ret == 0, "Failed to create/send onion packet.");
 
     handled_test_1 = 0;
@@ -91,6 +92,12 @@ START_TEST(test_basic)
 }
 END_TEST
 
+START_TEST(test_announce)
+{
+    
+    
+}
+END_TEST
 
 #define DEFTESTCASE(NAME) \
     TCase *tc_##NAME = tcase_create(#NAME); \
@@ -105,6 +112,7 @@ Suite *onion_suite(void)
     Suite *s = suite_create("Onion");
 
     DEFTESTCASE_SLOW(basic, 5);
+    DEFTESTCASE_SLOW(announce, 5);
     return s;
 }
 

docs/Prevent_Tracking.txt

@@ -104,8 +104,9 @@ encrypted (with our real long term private key if we want to announce ourselves,
 add the part used to send data to our list (if the list is full make it replace the furthest entry))
 
 data to route request packet:
-[uint8_t packet id (133)][public key of destination node][nonce][temporary just generated public key]encrypted with that temporary private key and the nonce:[data]
-(if Node D contains the used to send data for, it sends the stuff in this packet as a data to route response packet to the right node)
+[uint8_t packet id (133)][public key of destination node][nonce][temporary just generated public key]
+encrypted with that temporary private key and the nonce and the real public key of the destination node:[data]
+(if Node D contains the ret data for the node, it sends the stuff in this packet as a data to route response packet to the right node)
 
 Data sent to us:
 announce response packet:
@@ -114,8 +115,8 @@ encrypted with the DHT private key of Node D, the public key in the request and
 (if the ping id is zero, it means the information to reach the client id we are searching for is stored on this node)
 
 data to route response packet:
-[uint8_t packet id (134)][nonce]encrypted with that temporary private key and the nonce:[data]
-
+[uint8_t packet id (134)][nonce][temporary just generated public key]
+encrypted with that temporary private key and the nonce and the real public key of the destination node:[data]
 Onion packet (response):
 
 initial (sent from node D to node C):

toxcore/Makefile.inc

@@ -31,6 +31,8 @@ libtoxcore_la_SOURCES = ../toxcore/DHT.h \
                         ../toxcore/assoc.c \
                         ../toxcore/onion.h \
                         ../toxcore/onion.c \
+                        ../toxcore/onion_announce.h \
+                        ../toxcore/onion_announce.c \
                         ../toxcore/misc_tools.h
 
 libtoxcore_la_CFLAGS =  -I$(top_srcdir) \

toxcore/onion.h

@@ -20,6 +20,9 @@
 *
 */
 
+#ifndef ONION_H
+#define ONION_H
+
 #include "DHT.h"
 
 typedef struct {
@@ -58,3 +61,6 @@ int send_onion_response(Networking_Core *net, IP_Port dest, uint8_t *data, uint3
 Onion *new_onion(DHT *dht);
 
 void kill_onion(Onion *onion);
+
+
+#endif

toxcore/onion_announce.c

@@ -34,6 +34,8 @@
 #define ANNOUNCE_RESPONSE_MIN_SIZE (1 + crypto_box_NONCEBYTES + PING_ID_SIZE + crypto_box_MACBYTES)
 #define ANNOUNCE_RESPONSE_MAX_SIZE (ANNOUNCE_RESPONSE_MIN_SIZE + sizeof(Node_format)*MAX_SENT_NODES)
 
+#define DATA_REQUEST_MIN_SIZE (1 + crypto_box_PUBLICKEYBYTES + crypto_box_NONCEBYTES + crypto_box_PUBLICKEYBYTES + crypto_box_MACBYTES + ONION_RETURN_3)
+
 /* Generate a ping_id and put it in ping_id */
 static void generate_ping_id(Onion_Announce *onion_a, uint64_t time, uint8_t *public_key, uint8_t *ret,
                              uint8_t *ping_id)
@@ -47,26 +49,89 @@ static void generate_ping_id(Onion_Announce *onion_a, uint64_t time, uint8_t *pu
     crypto_hash_sha256(ping_id, data, sizeof(data));
 }
 
+/* check if public key is in entries list
+ *
+ * return -1 if no
+ * return position in list if yes
+ */
+static int in_entries(Onion_Announce *onion_a, uint8_t *public_key)
+{
+    uint32_t i;
+
+    for (i = 0; i < ONION_ANNOUNCE_MAX_ENTRIES; ++i) {
+        if (!is_timeout(onion_a->entries[i].time, ONION_ANNOUNCE_TIMEOUT)
+                && memcpy(onion_a->entries[i].public_key, public_key, crypto_box_PUBLICKEYBYTES) == 0)
+            return i;
+    }
+
+    return -1;
+}
+
+uint8_t cmp_public_key[crypto_box_PUBLICKEYBYTES];
+static int cmp_entry(const void *a, const void *b)
+{
+    Onion_Announce_Entry entry1, entry2;
+    memcpy(&entry1, a, sizeof(Onion_Announce_Entry));
+    memcpy(&entry2, b, sizeof(Onion_Announce_Entry));
+    int t1 = is_timeout(entry1.time, ONION_ANNOUNCE_TIMEOUT);
+    int t2 = is_timeout(entry2.time, ONION_ANNOUNCE_TIMEOUT);
+
+    if (t1 && t2)
+        return 0;
+
+    if (t1)
+        return -1;
+
+    if (t2)
+        return 1;
+
+    int close = id_closest(cmp_public_key, entry1.public_key, entry2.public_key);
+
+    if (close == 1)
+        return 1;
+
+    if (close == 2)
+        return -1;
+
+    return 0;
+}
+
 /* add entry to entries list
  *
  * return 0 if failure
  * return 1 if added
  */
-static int add_to_entries(Onion_Announce *onion_a, uint8_t *public_key, uint8_t *ret)
+static int add_to_entries(Onion_Announce *onion_a, IP_Port ret_ip_port, uint8_t *public_key, uint8_t *ret)
 {
 
-    return 0;
-}
+    int pos = in_entries(onion_a, public_key);
 
-/* check if public key is in entries list
- *
- * return 0 if no
- * return 1 if yes
- */
-static int in_entries(Onion_Announce *onion_a, uint8_t *public_key)
-{
+    uint32_t i;
 
-    return 0;
+    if (pos == -1) {
+        for (i = 0; i < ONION_ANNOUNCE_MAX_ENTRIES; ++i) {
+            if (is_timeout(onion_a->entries[i].time, ONION_ANNOUNCE_TIMEOUT))
+                pos = i;
+        }
+    }
+
+    if (pos == -1) {
+        if (id_closest(onion_a->dht->self_public_key, public_key, onion_a->entries[0].public_key) == 1)
+            pos = 0;
+    }
+
+    if (pos == -1)
+        return 0;
+
+
+    memcpy(onion_a->entries[pos].public_key, public_key, crypto_box_PUBLICKEYBYTES);
+    onion_a->entries[pos].ret_ip_port = ret_ip_port;
+    memcpy(onion_a->entries[pos].ret, ret, ONION_RETURN_3);
+    onion_a->entries[pos].time = unix_time();
+
+    memcpy(cmp_public_key, onion_a->dht->self_public_key, crypto_box_PUBLICKEYBYTES);
+    qsort(onion_a->entries, ONION_ANNOUNCE_MAX_ENTRIES, sizeof(Onion_Announce_Entry), cmp_entry);
+    return 1;
 }
 
 static int handle_announce_request(void *object, IP_Port source, uint8_t *packet, uint32_t length)
@@ -95,10 +160,10 @@ static int handle_announce_request(void *object, IP_Port source, uint8_t *packet
     int stored = 0;
 
     if (memcmp(ping_id1, plain, PING_ID_SIZE) == 0 || memcmp(ping_id2, plain, PING_ID_SIZE) == 0) {
-        stored = add_to_entries(onion_a, packet + 1 + crypto_box_NONCEBYTES,
+        stored = add_to_entries(onion_a, source, packet + 1 + crypto_box_NONCEBYTES,
                                 packet + (ANNOUNCE_REQUEST_SIZE - ONION_RETURN_3));
     } else {
-        stored = in_entries(onion_a, plain + PING_ID_SIZE);
+        stored = (in_entries(onion_a, plain + PING_ID_SIZE) != -1);
     }
 
     /*Respond with a announce response packet*/
@@ -138,6 +203,25 @@ static int handle_data_request(void *object, IP_Port source, uint8_t *packet, ui
 {
     Onion_Announce *onion_a = object;
 
+    if (length <= DATA_REQUEST_MIN_SIZE)
+        return 1;
+
+    if (length >= MAX_DATA_SIZE)
+        return 1;
+
+    int index = in_entries(onion_a, packet + 1);
+
+    if (index == -1)
+        return 1;
+
+    uint8_t data[length - (crypto_box_PUBLICKEYBYTES + ONION_RETURN_3)];
+    data[0] = NET_PACKET_ONION_DATA_RESPONSE;
+    memcpy(data + 1, packet + 1 + crypto_box_PUBLICKEYBYTES, length - (1 + crypto_box_PUBLICKEYBYTES + ONION_RETURN_3));
+
+    if (send_onion_response(onion_a->net, onion_a->entries[index].ret_ip_port, data, sizeof(data),
+                            onion_a->entries[index].ret) == -1)
+        return 1;
+
     return 0;
 }
 

toxcore/onion_announce.h

@@ -20,17 +20,25 @@
 *
 */
 
+#ifndef ONION_ANNOUNCE_H
+#define ONION_ANNOUNCE_H
+
 #include "onion.h"
 
 #define ONION_ANNOUNCE_MAX_ENTRIES 32
+#define ONION_ANNOUNCE_TIMEOUT 300
+
+typedef struct {
+        uint8_t public_key[crypto_box_PUBLICKEYBYTES];
+        IP_Port ret_ip_port;
+        uint8_t ret[ONION_RETURN_3];
+        uint64_t time;
+} Onion_Announce_Entry;
+
 typedef struct {
     DHT     *dht;
     Networking_Core *net;
-    struct {
-        uint8_t public_key[crypto_box_PUBLICKEYBYTES];
-        IP_Port first;
-        uint8_t ret[ONION_RETURN_3];
-    } entries[ONION_ANNOUNCE_MAX_ENTRIES];
+    Onion_Announce_Entry entries[ONION_ANNOUNCE_MAX_ENTRIES];
     /* This is crypto_secretbox_KEYBYTES long just so we can use new_symmetric_key() to fill it */
     uint8_t secret_bytes[crypto_secretbox_KEYBYTES];
 } Onion_Announce;
@@ -40,3 +48,6 @@ typedef struct {
 Onion_Announce *new_onion_announce(DHT *dht);
 
 void kill_onion_announce(Onion_Announce *onion_a);
+
+
+#endif