2 files changed, 702 insertions, 0 deletions

diff --git a/toxcore/group_chats.c b/toxcore/group_chats.c
new file mode 100644
index 00000000..3c134348
--- /dev/null
+++ b/toxcore/group_chats.c
@@ -0,0 +1,579 @@
+/* group_chats.c
+ *
+ * An implementation of massive text only group chats.
+ *
+ *
+ *  Copyright (C) 2013 Tox project All Rights Reserved.
+ *
+ *  This file is part of Tox.
+ *
+ *  Tox is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  Tox is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with Tox.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "group_chats.h"
+
+
+#define GROUPCHAT_MAXDATA_LENGTH (MAX_DATA_SIZE - (1 + crypto_box_PUBLICKEYBYTES * 2 + crypto_box_NONCEBYTES))
+#define GROUPCHAT_MAXPLAINDATA_LENGTH (GROUPCHAT_MAXDATA_LENGTH - crypto_box_MACBYTES)
+
+#define GROUP_MAX_SENDNODES (GROUP_CLOSE_CONNECTIONS * 2)
+
+typedef struct {
+    uint64_t   pingid;
+    //uint8_t    client_id[crypto_box_PUBLICKEYBYTES];
+
+} getnodes_data;
+
+typedef struct {
+    uint8_t    client_id[crypto_box_PUBLICKEYBYTES];
+    IP_Port    ip_port;
+
+} groupchat_nodes;
+
+typedef struct {
+    uint64_t   pingid;
+    groupchat_nodes nodes[GROUP_CLOSE_CONNECTIONS];
+    //uint8_t    client_id[crypto_box_PUBLICKEYBYTES];
+
+} sendnodes_data;
+
+/* Compares client_id1 and client_id2 with client_id
+ * return 0 if both are same distance
+ * return 1 if client_id1 is closer
+ * return 2 if client_id2 is closer
+ */
+static int id_closest(uint8_t *id, uint8_t *id1, uint8_t *id2)
+{
+    size_t   i;
+    uint8_t distance1, distance2;
+
+    for (i = 0; i < CLIENT_ID_SIZE; ++i) {
+
+        distance1 = abs(((int8_t *)id)[i] ^ ((int8_t *)id1)[i]);
+        distance2 = abs(((int8_t *)id)[i] ^ ((int8_t *)id2)[i]);
+
+        if (distance1 < distance2)
+            return 1;
+
+        if (distance1 > distance2)
+            return 2;
+    }
+
+    return 0;
+}
+
+
+/*
+ * check if peer with client_id is in peer array.
+ *
+ * return peer number if peer is in chat.
+ * return -1 if peer is not in chat.
+ *
+ * TODO: make this more efficient.
+ */
+
+static int peer_in_chat(Group_Chat *chat, uint8_t *client_id)
+{
+    uint32_t i;
+
+    for (i = 0; i < chat->numpeers; ++i) {
+        /* Equal */
+        if (memcmp(chat->group[i].client_id, client_id, crypto_box_PUBLICKEYBYTES) == 0)
+            return i;
+    }
+
+    return -1;
+}
+
+#define BAD_NODE_TIMEOUT 30
+
+/*
+ * Check if peer is closer to us that the other peers in the list and if the peer is in the list.
+ * Return the number of peers it is closer to if it is not in the closelist.
+ * Return -1 if the peer is in the closelist.
+ */
+
+static int peer_okping(Group_Chat *chat, uint8_t *client_id)
+{
+    uint32_t i, j = 0;
+    uint64_t temp_time = unix_time();
+
+    if (memcmp(chat->self_public_key, client_id, crypto_box_PUBLICKEYBYTES) == 0)
+        return -1;
+
+    for (i = 0; i < GROUP_CLOSE_CONNECTIONS; ++i) {
+        if (chat->close[i].last_recv + BAD_NODE_TIMEOUT < temp_time) {
+            ++j;
+            continue;
+        }
+
+        /* Equal */
+        if (memcmp(chat->close[i].client_id, client_id, crypto_box_PUBLICKEYBYTES) == 0)
+            return -1;
+
+        if (id_closest(chat->self_public_key, chat->close[i].client_id, client_id) == 2)
+            ++j;
+    }
+
+    return j;
+}
+
+
+
+/* Attempt to add a peer to the close list.
+ * Update last_recv if it is in list.
+ * Attempt to add it to list if it is not.
+ *
+ * Return 0 if success.
+ * Return -1 if peer was not put in list/updated.
+ */
+static int add_closepeer(Group_Chat *chat, uint8_t *client_id, IP_Port ip_port)
+{
+    uint32_t i;
+    uint64_t temp_time = unix_time();
+
+    for (i = 0; i < GROUP_CLOSE_CONNECTIONS; ++i) { /* Check if node is already in list, if it is update its last_recv */
+        if (memcmp(chat->close[i].client_id, client_id, crypto_box_PUBLICKEYBYTES) == 0) {
+            chat->close[i].last_recv = temp_time;
+            return 0;
+        }
+    }
+
+    for (i = 0; i < GROUP_CLOSE_CONNECTIONS; ++i) { /* Try replacing bad nodes first */
+        if (chat->close[i].last_recv + BAD_NODE_TIMEOUT < temp_time) {
+            memcpy(chat->close[i].client_id, client_id, crypto_box_PUBLICKEYBYTES);
+            chat->close[i].ip_port = ip_port;
+            chat->close[i].last_recv = temp_time;
+            return 0;
+        }
+    }
+
+    for (i = 0; i < GROUP_CLOSE_CONNECTIONS; ++i) { /* Replace nodes if given one is closer. */
+        if (id_closest(chat->self_public_key, chat->close[i].client_id, client_id) == 2) {
+            memcpy(chat->close[i].client_id, client_id, crypto_box_PUBLICKEYBYTES);
+            chat->close[i].ip_port = ip_port;
+            chat->close[i].last_recv = temp_time;
+            return 0;
+        }
+    }
+
+    return -1;
+}
+
+static int send_groupchatpacket(Group_Chat *chat, IP_Port ip_port, uint8_t *public_key, uint8_t *data, uint32_t length,
+                                uint8_t request_id)
+{
+    if (memcmp(chat->self_public_key, public_key, crypto_box_PUBLICKEYBYTES) == 0)
+        return -1;
+
+    uint8_t packet[MAX_DATA_SIZE];
+    int len = create_request(chat->self_public_key, chat->self_secret_key, packet, public_key, data, length, request_id);
+    packet[0] = 48;
+
+    if (len == -1)
+        return -1;
+
+    if (sendpacket(chat->net->sock, ip_port, packet, len) == len)
+        return 0;
+
+    return -1;
+
+}
+
+/*
+ * Send data to all peers in close peer list.
+ *
+ * return the number of peers the packet was sent to.
+ */
+static uint8_t sendto_allpeers(Group_Chat *chat, uint8_t *data, uint16_t length, uint8_t request_id)
+{
+    uint16_t sent = 0;
+    uint32_t i;
+    uint64_t temp_time = unix_time();
+
+    for (i = 0; i < GROUP_CLOSE_CONNECTIONS; ++i) {
+        if (chat->close[i].ip_port.ip.uint32 != 0 && chat->close[i].last_recv + BAD_NODE_TIMEOUT > temp_time) {
+            if (send_groupchatpacket(chat, chat->close[i].ip_port, chat->close[i].client_id, data, length, request_id) == 0)
+                ++sent;
+        }
+    }
+
+    return sent;
+}
+
+
+/*
+ * Add a peer to the group chat.
+ *
+ * return peernum if success or peer already in chat.
+ * return -1 if error.
+ */
+static int addpeer(Group_Chat *chat, uint8_t *client_id)
+{
+    int peernum = peer_in_chat(chat, client_id);
+
+    if (peernum != -1)
+        return peernum;
+
+    Group_Peer *temp;
+    temp = realloc(chat->group, sizeof(Group_Peer) * (chat->numpeers + 1));
+    memset(&(temp[chat->numpeers]), 0, sizeof(Group_Peer));
+
+    if (temp == NULL)
+        return -1;
+
+    chat->group = temp;
+    memcpy(chat->group[chat->numpeers].client_id, client_id, crypto_box_PUBLICKEYBYTES);
+    ++chat->numpeers;
+    return (chat->numpeers - 1);
+}
+
+/*
+ * Delete a peer to the group chat.
+ *
+ * return 0 if success
+ * return -1 if error.
+ */
+static int delpeer(Group_Chat *chat, uint8_t *client_id)
+{
+    uint32_t i;
+    Group_Peer *temp;
+
+    for (i = 0; i < chat->numpeers; ++i) {
+        /* Equal */
+        if (memcmp(chat->group[i].client_id, client_id, crypto_box_PUBLICKEYBYTES) == 0) {
+            --chat->numpeers;
+
+            if (chat->numpeers != i) {
+                memcpy( chat->group[i].client_id,
+                        chat->group[chat->numpeers].client_id,
+                        crypto_box_PUBLICKEYBYTES );
+            }
+
+            temp = realloc(chat->group, sizeof(Group_Peer) * (chat->numpeers));
+
+            if (temp == NULL)
+                return -1;
+
+            chat->group = temp;
+            return 0;
+        }
+    }
+
+    return -1;
+}
+/* min time between pings sent to one peer in seconds */
+#define PING_TIMEOUT 5
+static int send_getnodes(Group_Chat *chat, IP_Port ip_port, int peernum)
+{
+    if ((uint32_t)peernum >= chat->numpeers)
+        return -1;
+
+    uint64_t temp_time = unix_time();
+
+    getnodes_data contents;
+
+    if (chat->group[peernum].last_pinged + PING_TIMEOUT > temp_time)
+        return -1;
+
+    contents.pingid = ((uint64_t)random_int() << 32) + random_int();
+    chat->group[peernum].last_pinged = temp_time;
+    chat->group[peernum].pingid = contents.pingid;
+    return send_groupchatpacket(chat, ip_port, chat->group[peernum].client_id, (uint8_t *)&contents, sizeof(contents), 48);
+}
+
+static int send_sendnodes(Group_Chat *chat, IP_Port ip_port, int peernum, uint64_t pingid)
+{
+    if ((uint32_t)peernum >= chat->numpeers)
+        return -1;
+
+    sendnodes_data contents;
+    contents.pingid = pingid;
+    uint32_t i, j = 0;
+    uint64_t temp_time = unix_time();
+
+    for (i = 0; i < GROUP_CLOSE_CONNECTIONS; ++i) {
+        if (chat->close[i].last_recv + BAD_NODE_TIMEOUT > temp_time) {
+            memcpy(contents.nodes[j].client_id, chat->close[i].client_id, crypto_box_PUBLICKEYBYTES);
+            contents.nodes[j].ip_port = chat->close[i].ip_port;
+            ++j;
+        }
+    }
+
+    return send_groupchatpacket(chat, ip_port, chat->group[peernum].client_id, (uint8_t *)&contents,
+                                sizeof(contents.pingid) + sizeof(groupchat_nodes) * j, 49);
+}
+
+static int handle_getnodes(Group_Chat *chat, IP_Port source, int peernum, uint8_t *data, uint32_t len)
+{
+    if (len != sizeof(getnodes_data))
+        return 1;
+
+    if ((uint32_t)peernum >= chat->numpeers)
+        return 1;
+
+    getnodes_data contents;
+    memcpy(&contents, data, sizeof(contents));
+    send_sendnodes(chat, source, peernum, contents.pingid);
+
+    if (peer_okping(chat, chat->group[peernum].client_id) > 0)
+        send_getnodes(chat, source, peernum);
+
+    return 0;
+}
+
+static int handle_sendnodes(Group_Chat *chat, IP_Port source, int peernum, uint8_t *data, uint32_t len)
+{
+    if ((uint32_t)peernum >= chat->numpeers)
+        return 1;
+
+    if (len > sizeof(sendnodes_data) || len < sizeof(uint64_t))
+        return 1;
+
+    if ((len - sizeof(uint64_t)) % sizeof(groupchat_nodes) != 0)
+        return 1;
+
+    if (chat->group[peernum].last_pinged + PING_TIMEOUT < unix_time())
+        return 1;
+
+    sendnodes_data contents;
+    memcpy(&contents, data, len);
+
+    if (contents.pingid != chat->group[peernum].pingid)
+        return 1;
+
+    uint16_t numnodes = (len - sizeof(contents.pingid)) / sizeof(groupchat_nodes);
+    uint32_t i;
+
+    for (i = 0; i < numnodes; ++i) {
+        if (peer_okping(chat, contents.nodes[i].client_id) > 0) {
+            int peern = peer_in_chat(chat, contents.nodes[i].client_id);
+
+            if (peern == -1) { /*NOTE: This is just for testing and will be removed later.*/
+                peern = addpeer(chat, contents.nodes[i].client_id);
+            }
+
+            if (peern == -1)
+                continue;
+
+            send_getnodes(chat, contents.nodes[i].ip_port, peern);
+        }
+    }
+
+    add_closepeer(chat, chat->group[peernum].client_id, source);
+    return 0;
+}
+#define GROUP_DATA_MIN_SIZE (crypto_box_PUBLICKEYBYTES + sizeof(uint32_t) + 1)
+static int handle_data(Group_Chat *chat, uint8_t *data, uint32_t len)
+{
+    if (len < GROUP_DATA_MIN_SIZE)
+        return 1;
+
+//TODO:
+    int peernum = peer_in_chat(chat, data);
+
+    if (peernum == -1) { /*NOTE: This is just for testing and will be removed later.*/
+        peernum = addpeer(chat, data);
+    }
+
+    if (peernum == -1)
+        return 1;
+
+    uint64_t temp_time = unix_time();
+    /* Spam prevention (1 message per peer per second limit.)
+
+        if (chat->group[peernum].last_recv == temp_time)
+            return 1;
+
+        chat->group[peernum].last_recv = temp_time;
+    */
+    uint32_t message_num;
+    memcpy(&message_num, data + crypto_box_PUBLICKEYBYTES, sizeof(uint32_t));
+    message_num = ntohl(message_num);
+
+    if (chat->group[peernum].last_message_number == 0) {
+        chat->group[peernum].last_message_number = message_num;
+    } else if (message_num - chat->group[peernum].last_message_number > 64 ||
+               message_num == chat->group[peernum].last_message_number)
+        return 1;
+
+    chat->group[peernum].last_message_number = message_num;
+
+    int handled = 1;
+    uint8_t *contents = data + GROUP_DATA_MIN_SIZE;
+    uint16_t contents_len = len - GROUP_DATA_MIN_SIZE;
+
+    switch (data[crypto_box_PUBLICKEYBYTES + sizeof(message_num)]) {
+        case 0: /* If message is ping */
+            if (contents_len != 0)
+                return 1;
+
+            chat->group[peernum].last_recv_msgping = temp_time;
+
+        case 16: /* If message is new peer */
+            if (contents_len != crypto_box_PUBLICKEYBYTES)
+                return 1;
+
+            addpeer(chat, contents);
+            break;
+
+        case 64: /* If message is chat message */
+            if (chat->group_message != NULL)
+                (*chat->group_message)(chat, peernum, contents, contents_len, chat->group_message_userdata);
+
+            break;
+
+        default:
+            handled = 0;
+            break;
+
+    }
+
+    if (handled == 1) {
+        sendto_allpeers(chat, data, len, 50);
+        return 0;
+    }
+
+    return 1;
+}
+
+static uint8_t send_data(Group_Chat *chat, uint8_t *data, uint32_t len, uint8_t message_id)
+{
+    if (len + GROUP_DATA_MIN_SIZE > MAX_DATA_SIZE) /*NOTE: not the real maximum len.*/
+        return 1;
+
+    uint8_t packet[MAX_DATA_SIZE];
+    ++chat->message_number;
+
+    if (chat->message_number == 0)
+        chat->message_number = 1;
+
+    uint32_t message_num = htonl(chat->message_number);
+//TODO
+    memcpy(packet, chat->self_public_key, crypto_box_PUBLICKEYBYTES);
+    memcpy(packet + crypto_box_PUBLICKEYBYTES, &message_num, sizeof(message_num));
+    memcpy(packet + GROUP_DATA_MIN_SIZE, data, len);
+    packet[crypto_box_PUBLICKEYBYTES + sizeof(message_num)] = message_id;
+    return sendto_allpeers(chat, packet, len + GROUP_DATA_MIN_SIZE, 50);
+}
+/*
+ * Handle get nodes group packet.
+ *
+ * return 0 if handled correctly.
+ * return 1 if error.
+ */
+
+int handle_groupchatpacket(Group_Chat *chat, IP_Port source, uint8_t *packet, uint32_t length)
+{
+    if (length > MAX_DATA_SIZE)
+        return 1;
+
+    uint8_t public_key[crypto_box_PUBLICKEYBYTES];
+    uint8_t data[MAX_DATA_SIZE];
+    uint8_t number;
+    int len = handle_request(chat->self_public_key, chat->self_secret_key, public_key, data, &number, packet, length);
+
+    if (len <= 0)
+        return 1;
+
+    if (memcmp(chat->self_public_key, public_key, crypto_box_PUBLICKEYBYTES) == 0)
+        return 1;
+
+    int peernum = peer_in_chat(chat, public_key);
+
+    if (peernum == -1)
+        return 1;
+
+    switch (number) {
+        case 48:
+            return handle_getnodes(chat, source, peernum, data, len);
+
+        case 49:
+            return handle_sendnodes(chat, source, peernum, data, len);
+
+        case 50:
+            return handle_data(chat, data, len);
+
+        default:
+            return 1;
+    }
+
+    return 1;
+}
+
+uint32_t group_sendmessage(Group_Chat *chat, uint8_t *message, uint32_t length)
+{
+    return send_data(chat, message, length, 64); //TODO: better return values?
+}
+
+uint32_t group_newpeer(Group_Chat *chat, uint8_t *client_id)
+{
+    addpeer(chat, client_id);
+    return send_data(chat, client_id, crypto_box_PUBLICKEYBYTES, 16); //TODO: better return values?
+}
+
+void callback_groupmessage(Group_Chat *chat, void (*function)(Group_Chat *chat, int, uint8_t *, uint16_t, void *),
+                           void *userdata)
+{
+    chat->group_message = function;
+    chat->group_message_userdata = userdata;
+}
+
+Group_Chat *new_groupchat(Networking_Core *net)
+{
+    if (net == 0)
+        return 0;
+
+    Group_Chat *chat = calloc(1, sizeof(Group_Chat));
+    chat->net = net;
+    crypto_box_keypair(chat->self_public_key, chat->self_secret_key);
+    return chat;
+}
+
+#define NODE_PING_INTERVAL 10
+
+static void ping_close(Group_Chat *chat)
+{
+    uint32_t i;
+    uint64_t temp_time = unix_time();
+
+    for (i = 0; i < GROUP_CLOSE_CONNECTIONS; ++i) {
+        if (chat->close[i].last_recv < temp_time + BAD_NODE_TIMEOUT) {
+            int peernum = peer_in_chat(chat, chat->close[i].client_id);
+
+            if (peernum == -1)
+                continue;
+
+            if (chat->group[peernum].last_pinged + NODE_PING_INTERVAL < temp_time)
+                send_getnodes(chat, chat->close[i].ip_port, peernum);
+        }
+    }
+}
+
+void do_groupchat(Group_Chat *chat)
+{
+    ping_close(chat);
+}
+
+void kill_groupchat(Group_Chat *chat)
+{
+    free(chat->group);
+    free(chat);
+}
+
+void chat_bootstrap(Group_Chat *chat, IP_Port ip_port, uint8_t *client_id)
+{
+    send_getnodes(chat, ip_port, addpeer(chat, client_id));
+}
diff --git a/toxcore/group_chats.h b/toxcore/group_chats.h
new file mode 100644
index 00000000..7af13d8d
--- /dev/null
+++ b/toxcore/group_chats.h
@@ -0,0 +1,123 @@
+/* group_chats.h
+ *
+ * An implementation of massive text only group chats.
+ *
+ *
+ *  Copyright (C) 2013 Tox project All Rights Reserved.
+ *
+ *  This file is part of Tox.
+ *
+ *  Tox is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  Tox is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with Tox.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef GROUP_CHATS_H
+#define GROUP_CHATS_H
+
+#include "net_crypto.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct {
+    uint8_t     client_id[crypto_box_PUBLICKEYBYTES];
+    uint64_t    pingid;
+    uint64_t    last_pinged;
+
+    uint64_t    last_recv;
+    uint64_t    last_recv_msgping;
+    uint32_t    last_message_number;
+} Group_Peer;
+
+typedef struct {
+    uint8_t     client_id[crypto_box_PUBLICKEYBYTES];
+    IP_Port     ip_port;
+    uint64_t    last_recv;
+
+} Group_Close;
+
+#define GROUP_CLOSE_CONNECTIONS 6
+
+typedef struct Group_Chat {
+    Networking_Core *net;
+    uint8_t     self_public_key[crypto_box_PUBLICKEYBYTES];
+    uint8_t     self_secret_key[crypto_box_SECRETKEYBYTES];
+
+    Group_Peer *group;
+    Group_Close  close[GROUP_CLOSE_CONNECTIONS];
+    uint32_t numpeers;
+
+    uint32_t message_number;
+    void (*group_message)(struct Group_Chat *m, int, uint8_t *, uint16_t, void *);
+    void *group_message_userdata;
+
+} Group_Chat;
+
+/*
+ * Set callback function for chat messages.
+ *
+ * format of function is: function(Group_Chat *chat, peer number, message, message length, userdata)
+ */
+
+void callback_groupmessage(Group_Chat *chat, void (*function)(Group_Chat *chat, int, uint8_t *, uint16_t, void *),
+                           void *userdata);
+
+/*
+ * Send a message to the group.
+ *
+ */
+uint32_t group_sendmessage(Group_Chat *chat, uint8_t *message, uint32_t length);
+
+
+/*
+ * Tell everyone about a new peer (a person we are inviting for example.)
+ *
+ */
+uint32_t group_newpeer(Group_Chat *chat, uint8_t *client_id);
+
+
+/* Create a new group chat.
+ *
+ * Returns a new group chat instance if success.
+ *
+ * Returns a NULL pointer if fail.
+ */
+Group_Chat *new_groupchat(Networking_Core *net);
+
+
+/* Kill a group chat
+ *
+ * Frees the memory and everything.
+ */
+void kill_groupchat(Group_Chat *chat);
+
+/*
+ * This is the main loop.
+ */
+void do_groupchat(Group_Chat *chat);
+
+/* if we receive a group chat packet we call this function so it can be handled.
+    return 0 if packet is handled correctly.
+    return 1 if it didn't handle the packet or if the packet was shit. */
+int handle_groupchatpacket(Group_Chat *chat, IP_Port source, uint8_t *packet, uint32_t length);
+
+
+void chat_bootstrap(Group_Chat *chat, IP_Port ip_port, uint8_t *client_id);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif