diff --git a/other/bootstrap_daemon/docker/tox-bootstrapd.sha256 b/other/bootstrap_daemon/docker/tox-bootstrapd.sha256
index 49660930..2a560715 100644
--- a/other/bootstrap_daemon/docker/tox-bootstrapd.sha256
+++ b/other/bootstrap_daemon/docker/tox-bootstrapd.sha256
@@ -1 +1 @@
-78791fce8556684ee8210d6b79b11c5fd7a2c35c96589aec4b8641a62b0414a3  /usr/local/bin/tox-bootstrapd
+7be4fcdc11f74036b97de9569eb06f82296f193db3e18e671171f3bc059f95a6  /usr/local/bin/tox-bootstrapd
diff --git a/toxcore/DHT.c b/toxcore/DHT.c
index 76b03429..2fb6a1f3 100644
--- a/toxcore/DHT.c
+++ b/toxcore/DHT.c
@@ -452,7 +452,8 @@ int pack_ip_port(uint8_t *data, uint16_t length, const IP_Port *ip_port)
 }
 
 static int dht_create_packet(const uint8_t public_key[CRYPTO_PUBLIC_KEY_SIZE],
-                             const uint8_t *shared_key, const uint8_t type, uint8_t *plain, size_t plain_length, uint8_t *packet)
+                             const uint8_t *shared_key, const uint8_t type,
+                             const uint8_t *plain, size_t plain_length, uint8_t *packet)
 {
     VLA(uint8_t, encrypted, plain_length + CRYPTO_MAC_SIZE);
     uint8_t nonce[CRYPTO_NONCE_SIZE];
@@ -1066,7 +1067,7 @@ static bool is_pk_in_client_list(const Client_data *list, unsigned int client_li
     return !assoc_timeout(cur_time, assoc);
 }
 
-static bool is_pk_in_close_list(DHT *dht, const uint8_t *public_key, IP_Port ip_port)
+static bool is_pk_in_close_list(const DHT *dht, const uint8_t *public_key, IP_Port ip_port)
 {
     unsigned int index = bit_by_bit_cmp(public_key, dht->self_public_key);
 
@@ -2124,7 +2125,7 @@ static int handle_NATping(void *object, IP_Port source, const uint8_t *source_pu
  *
  *  return ip of 0 if failure.
  */
-static IP nat_commonip(IP_Port *ip_portlist, uint16_t len, uint16_t min_num)
+static IP nat_commonip(const IP_Port *ip_portlist, uint16_t len, uint16_t min_num)
 {
     IP zero;
     ip_reset(&zero);
@@ -2156,7 +2157,7 @@ static IP nat_commonip(IP_Port *ip_portlist, uint16_t len, uint16_t min_num)
  *
  *  return number of ports and puts the list of ports in portlist.
  */
-static uint16_t nat_getports(uint16_t *portlist, IP_Port *ip_portlist, uint16_t len, IP ip)
+static uint16_t nat_getports(uint16_t *portlist, const IP_Port *ip_portlist, uint16_t len, IP ip)
 {
     uint16_t num = 0;
 
@@ -2279,8 +2280,8 @@ static void do_NAT(DHT *dht)
  *
  * return the number of nodes.
  */
-static uint16_t list_nodes(Client_data *list, size_t length, uint64_t cur_time, Node_format *nodes,
-                           uint16_t max_num)
+static uint16_t list_nodes(const Client_data *list, size_t length, uint64_t cur_time,
+                           Node_format *nodes, uint16_t max_num)
 {
     if (max_num == 0) {
         return 0;
diff --git a/toxcore/LAN_discovery.c b/toxcore/LAN_discovery.c
index 3e1c2863..d67b6f8d 100644
--- a/toxcore/LAN_discovery.c
+++ b/toxcore/LAN_discovery.c
@@ -369,7 +369,7 @@ static int handle_LANdiscovery(void *object, IP_Port source, const uint8_t *pack
 }
 
 
-int lan_discovery_send(uint16_t port, DHT *dht)
+int lan_discovery_send(uint16_t port, const DHT *dht)
 {
     uint8_t data[CRYPTO_PUBLIC_KEY_SIZE + 1];
     data[0] = NET_PACKET_LAN_DISCOVERY;
diff --git a/toxcore/LAN_discovery.h b/toxcore/LAN_discovery.h
index dcb9e532..4724d036 100644
--- a/toxcore/LAN_discovery.h
+++ b/toxcore/LAN_discovery.h
@@ -19,7 +19,7 @@
 /**
  * Send a LAN discovery pcaket to the broadcast address with port port.
  */
-int32_t lan_discovery_send(uint16_t port, DHT *dht);
+int32_t lan_discovery_send(uint16_t port, const DHT *dht);
 
 /**
  * Sets up packet handlers.
diff --git a/toxcore/Messenger.c b/toxcore/Messenger.c
index 4ccd106e..4e663589 100644
--- a/toxcore/Messenger.c
+++ b/toxcore/Messenger.c
@@ -1152,7 +1152,7 @@ long int new_filesender(const Messenger *m, int32_t friendnumber, uint32_t file_
 }
 
 static int send_file_control_packet(const Messenger *m, int32_t friendnumber, uint8_t send_receive, uint8_t filenumber,
-                                    uint8_t control_type, uint8_t *data, uint16_t data_length)
+                                    uint8_t control_type, const uint8_t *data, uint16_t data_length)
 {
     if ((unsigned int)(1 + 3 + data_length) > MAX_CRYPTO_DATA_SIZE) {
         return -1;
diff --git a/toxcore/TCP_client.c b/toxcore/TCP_client.c
index 04584f9d..63a921b1 100644
--- a/toxcore/TCP_client.c
+++ b/toxcore/TCP_client.c
@@ -148,7 +148,7 @@ static int proxy_http_generate_connection_request(TCP_Client_Connection *tcp_con
  * return 0 if no data received.
  * return -1 on failure (connection refused).
  */
-static int proxy_http_read_connection_response(const Logger *logger, TCP_Client_Connection *tcp_conn)
+static int proxy_http_read_connection_response(const Logger *logger, const TCP_Client_Connection *tcp_conn)
 {
     char success[] = "200";
     uint8_t data[16]; // draining works the best if the length is a power of 2
@@ -190,7 +190,7 @@ static void proxy_socks5_generate_handshake(TCP_Client_Connection *tcp_conn)
  * return 0 if no data received.
  * return -1 on failure (connection refused).
  */
-static int socks5_read_handshake_response(const Logger *logger, TCP_Client_Connection *tcp_conn)
+static int socks5_read_handshake_response(const Logger *logger, const TCP_Client_Connection *tcp_conn)
 {
     uint8_t data[2];
     int ret = read_TCP_packet(logger, tcp_conn->sock, data, sizeof(data));
@@ -236,7 +236,7 @@ static void proxy_socks5_generate_connection_request(TCP_Client_Connection *tcp_
  * return 0 if no data received.
  * return -1 on failure (connection refused).
  */
-static int proxy_socks5_read_connection_response(const Logger *logger, TCP_Client_Connection *tcp_conn)
+static int proxy_socks5_read_connection_response(const Logger *logger, const TCP_Client_Connection *tcp_conn)
 {
     if (net_family_is_ipv4(tcp_conn->ip_port.ip.family)) {
         uint8_t data[4 + sizeof(IP4) + sizeof(uint16_t)];
@@ -470,7 +470,7 @@ static int write_packet_TCP_client_secure_connection(TCP_Client_Connection *con,
  * return 0 if could not send packet.
  * return -1 on failure (connection must be killed).
  */
-int send_routing_request(TCP_Client_Connection *con, uint8_t *public_key)
+int send_routing_request(TCP_Client_Connection *con, const uint8_t *public_key)
 {
     uint8_t packet[1 + CRYPTO_PUBLIC_KEY_SIZE];
     packet[0] = TCP_PACKET_ROUTING_REQUEST;
@@ -957,8 +957,8 @@ static int do_confirmed_TCP(const Logger *logger, TCP_Client_Connection *conn, c
 
 /** Run the TCP connection
  */
-void do_TCP_connection(const Logger *logger, Mono_Time *mono_time, TCP_Client_Connection *tcp_connection,
-                       void *userdata)
+void do_TCP_connection(const Logger *logger, const Mono_Time *mono_time,
+                       TCP_Client_Connection *tcp_connection, void *userdata)
 {
     if (tcp_connection->status == TCP_CLIENT_DISCONNECTED) {
         return;
diff --git a/toxcore/TCP_client.h b/toxcore/TCP_client.h
index fed8b637..3a4f8df7 100644
--- a/toxcore/TCP_client.h
+++ b/toxcore/TCP_client.h
@@ -54,8 +54,8 @@ TCP_Client_Connection *new_TCP_connection(const Mono_Time *mono_time, IP_Port ip
 
 /** Run the TCP connection
  */
-void do_TCP_connection(const Logger *logger, Mono_Time *mono_time, TCP_Client_Connection *tcp_connection,
-                       void *userdata);
+void do_TCP_connection(const Logger *logger, const Mono_Time *mono_time,
+                       TCP_Client_Connection *tcp_connection, void *userdata);
 
 /** Kill the TCP connection
  */
@@ -77,7 +77,7 @@ typedef int tcp_routing_status_cb(void *object, uint32_t number, uint8_t connect
  * return 0 if could not send packet.
  * return -1 on failure (connection must be killed).
  */
-int send_routing_request(TCP_Client_Connection *con, uint8_t *public_key);
+int send_routing_request(TCP_Client_Connection *con, const uint8_t *public_key);
 void routing_response_handler(TCP_Client_Connection *con, tcp_routing_response_cb *response_callback, void *object);
 void routing_status_handler(TCP_Client_Connection *con, tcp_routing_status_cb *status_callback, void *object);
 
diff --git a/toxcore/TCP_connection.c b/toxcore/TCP_connection.c
index 57f1161b..9f6429e2 100644
--- a/toxcore/TCP_connection.c
+++ b/toxcore/TCP_connection.c
@@ -289,7 +289,8 @@ uint32_t tcp_connected_relays_count(const TCP_Connections *tcp_c)
  * return -1 on failure.
  * return 0 on success.
  */
-int send_packet_tcp_connection(TCP_Connections *tcp_c, int connections_number, const uint8_t *packet, uint16_t length)
+int send_packet_tcp_connection(const TCP_Connections *tcp_c, int connections_number, const uint8_t *packet,
+                               uint16_t length)
 {
     TCP_Connection_to *con_to = get_connection(tcp_c, connections_number);
 
@@ -372,7 +373,7 @@ int send_packet_tcp_connection(TCP_Connections *tcp_c, int connections_number, c
  * return TCP connection number on success.
  * return -1 on failure.
  */
-int get_random_tcp_onion_conn_number(TCP_Connections *tcp_c)
+int get_random_tcp_onion_conn_number(const TCP_Connections *tcp_c)
 {
     const uint32_t r = random_u32();
 
@@ -415,8 +416,8 @@ int tcp_send_onion_request(TCP_Connections *tcp_c, uint32_t tcp_connections_numb
  * return 0 on success.
  * return -1 on failure.
  */
-int tcp_send_oob_packet(TCP_Connections *tcp_c, unsigned int tcp_connections_number, const uint8_t *public_key,
-                        const uint8_t *packet, uint16_t length)
+int tcp_send_oob_packet(const TCP_Connections *tcp_c, unsigned int tcp_connections_number,
+                        const uint8_t *public_key, const uint8_t *packet, uint16_t length)
 {
     TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_connections_number);
 
@@ -437,14 +438,14 @@ int tcp_send_oob_packet(TCP_Connections *tcp_c, unsigned int tcp_connections_num
     return -1;
 }
 
-static int find_tcp_connection_relay(TCP_Connections *tcp_c, const uint8_t *relay_pk);
+static int find_tcp_connection_relay(const TCP_Connections *tcp_c, const uint8_t *relay_pk);
 
 /** Send an oob packet via the TCP relay corresponding to relay_pk.
  *
  * return 0 on success.
  * return -1 on failure.
  */
-int tcp_send_oob_packet_using_relay(TCP_Connections *tcp_c, const uint8_t *relay_pk, const uint8_t *public_key,
+int tcp_send_oob_packet_using_relay(const TCP_Connections *tcp_c, const uint8_t *relay_pk, const uint8_t *public_key,
                                     const uint8_t *packet, uint16_t length)
 {
     int tcp_con_number = find_tcp_connection_relay(tcp_c, relay_pk);
@@ -485,7 +486,7 @@ void set_onion_packet_tcp_connection_callback(TCP_Connections *tcp_c, tcp_onion_
  * return connections_number on success.
  * return -1 on failure.
  */
-static int find_tcp_connection_to(TCP_Connections *tcp_c, const uint8_t *public_key)
+static int find_tcp_connection_to(const TCP_Connections *tcp_c, const uint8_t *public_key)
 {
     for (unsigned int i = 0; i < tcp_c->connections_length; ++i) {
         TCP_Connection_to *con_to = get_connection(tcp_c, i);
@@ -505,7 +506,7 @@ static int find_tcp_connection_to(TCP_Connections *tcp_c, const uint8_t *public_
  * return connections_number on success.
  * return -1 on failure.
  */
-static int find_tcp_connection_relay(TCP_Connections *tcp_c, const uint8_t *relay_pk)
+static int find_tcp_connection_relay(const TCP_Connections *tcp_c, const uint8_t *relay_pk)
 {
     for (uint32_t i = 0; i < tcp_c->tcp_connections_length; ++i) {
         TCP_con *tcp_con = get_tcp_connection(tcp_c, i);
@@ -603,7 +604,7 @@ int kill_tcp_connection_to(TCP_Connections *tcp_c, int connections_number)
  * return 0 on success.
  * return -1 on failure.
  */
-int set_tcp_connection_to_status(TCP_Connections *tcp_c, int connections_number, bool status)
+int set_tcp_connection_to_status(const TCP_Connections *tcp_c, int connections_number, bool status)
 {
     TCP_Connection_to *con_to = get_connection(tcp_c, connections_number);
 
@@ -660,7 +661,7 @@ int set_tcp_connection_to_status(TCP_Connections *tcp_c, int connections_number,
     return 0;
 }
 
-static bool tcp_connection_in_conn(TCP_Connection_to *con_to, unsigned int tcp_connections_number)
+static bool tcp_connection_in_conn(const TCP_Connection_to *con_to, unsigned int tcp_connections_number)
 {
     for (unsigned int i = 0; i < MAX_FRIEND_TCP_CONNECTIONS; ++i) {
         if (con_to->connections[i].tcp_connection == (tcp_connections_number + 1)) {
@@ -712,7 +713,7 @@ static int rm_tcp_connection_from_conn(TCP_Connection_to *con_to, unsigned int t
 /** return number of online connections on success.
  * return -1 on failure.
  */
-static unsigned int online_tcp_connection_from_conn(TCP_Connection_to *con_to)
+static unsigned int online_tcp_connection_from_conn(const TCP_Connection_to *con_to)
 {
     unsigned int count = 0;
 
@@ -903,7 +904,7 @@ static int unsleep_tcp_relay_connection(TCP_Connections *tcp_c, int tcp_connecti
  * return 0 on success.
  * return -1 on failure.
  */
-static int send_tcp_relay_routing_request(TCP_Connections *tcp_c, int tcp_connections_number, uint8_t *public_key)
+static int send_tcp_relay_routing_request(const TCP_Connections *tcp_c, int tcp_connections_number, uint8_t *public_key)
 {
     TCP_con *tcp_con = get_tcp_connection(tcp_c, tcp_connections_number);
 
@@ -1266,7 +1267,7 @@ int add_tcp_relay_connection(TCP_Connections *tcp_c, int connections_number, IP_
 /** return number of online tcp relays tied to the connection on success.
  * return 0 on failure.
  */
-unsigned int tcp_connection_to_online_tcp_relays(TCP_Connections *tcp_c, int connections_number)
+unsigned int tcp_connection_to_online_tcp_relays(const TCP_Connections *tcp_c, int connections_number)
 {
     TCP_Connection_to *con_to = get_connection(tcp_c, connections_number);
 
@@ -1283,7 +1284,7 @@ unsigned int tcp_connection_to_online_tcp_relays(TCP_Connections *tcp_c, int con
  * return number of relays copied to tcp_relays on success.
  * return 0 on failure.
  */
-uint32_t tcp_copy_connected_relays(TCP_Connections *tcp_c, Node_format *tcp_relays, uint16_t max_num)
+uint32_t tcp_copy_connected_relays(const TCP_Connections *tcp_c, Node_format *tcp_relays, uint16_t max_num)
 {
     const uint32_t r = random_u32();
     uint32_t copied = 0;
@@ -1387,7 +1388,7 @@ int set_tcp_onion_status(TCP_Connections *tcp_c, bool status)
  *
  * Returns NULL on failure.
  */
-TCP_Connections *new_tcp_connections(Mono_Time *mono_time, const uint8_t *secret_key, TCP_Proxy_Info *proxy_info)
+TCP_Connections *new_tcp_connections(Mono_Time *mono_time, const uint8_t *secret_key, const TCP_Proxy_Info *proxy_info)
 {
     if (secret_key == nullptr) {
         return nullptr;
diff --git a/toxcore/TCP_connection.h b/toxcore/TCP_connection.h
index d27b3e94..627c40c4 100644
--- a/toxcore/TCP_connection.h
+++ b/toxcore/TCP_connection.h
@@ -80,7 +80,8 @@ uint32_t tcp_connected_relays_count(const TCP_Connections *tcp_c);
  * return -1 on failure.
  * return 0 on success.
  */
-int send_packet_tcp_connection(TCP_Connections *tcp_c, int connections_number, const uint8_t *packet, uint16_t length);
+int send_packet_tcp_connection(const TCP_Connections *tcp_c, int connections_number, const uint8_t *packet,
+                               uint16_t length);
 
 /** Return a random TCP connection number for use in send_tcp_onion_request.
  *
@@ -90,7 +91,7 @@ int send_packet_tcp_connection(TCP_Connections *tcp_c, int connections_number, c
  * return TCP connection number on success.
  * return -1 on failure.
  */
-int get_random_tcp_onion_conn_number(TCP_Connections *tcp_c);
+int get_random_tcp_onion_conn_number(const TCP_Connections *tcp_c);
 
 /** Send an onion packet via the TCP relay corresponding to tcp_connections_number.
  *
@@ -114,12 +115,12 @@ int set_tcp_onion_status(TCP_Connections *tcp_c, bool status);
  * return 0 on success.
  * return -1 on failure.
  */
-int tcp_send_oob_packet(TCP_Connections *tcp_c, unsigned int tcp_connections_number, const uint8_t *public_key,
+int tcp_send_oob_packet(const TCP_Connections *tcp_c, unsigned int tcp_connections_number, const uint8_t *public_key,
                         const uint8_t *packet, uint16_t length);
 
 typedef int tcp_data_cb(void *object, int id, const uint8_t *data, uint16_t length, void *userdata);
 
-int tcp_send_oob_packet_using_relay(TCP_Connections *tcp_c, const uint8_t *relay_pk, const uint8_t *public_key,
+int tcp_send_oob_packet_using_relay(const TCP_Connections *tcp_c, const uint8_t *relay_pk, const uint8_t *public_key,
                                     const uint8_t *packet, uint16_t length);
 
 /** Set the callback for TCP data packets.
@@ -165,12 +166,12 @@ int kill_tcp_connection_to(TCP_Connections *tcp_c, int connections_number);
  * return 0 on success.
  * return -1 on failure.
  */
-int set_tcp_connection_to_status(TCP_Connections *tcp_c, int connections_number, bool status);
+int set_tcp_connection_to_status(const TCP_Connections *tcp_c, int connections_number, bool status);
 
 /** return number of online tcp relays tied to the connection on success.
  * return 0 on failure.
  */
-unsigned int tcp_connection_to_online_tcp_relays(TCP_Connections *tcp_c, int connections_number);
+unsigned int tcp_connection_to_online_tcp_relays(const TCP_Connections *tcp_c, int connections_number);
 
 /** Add a TCP relay tied to a connection.
  *
@@ -205,7 +206,7 @@ int add_tcp_relay_global(TCP_Connections *tcp_c, IP_Port ip_port, const uint8_t
  * return number of relays copied to tcp_relays on success.
  * return 0 on failure.
  */
-uint32_t tcp_copy_connected_relays(TCP_Connections *tcp_c, Node_format *tcp_relays, uint16_t max_num);
+uint32_t tcp_copy_connected_relays(const TCP_Connections *tcp_c, Node_format *tcp_relays, uint16_t max_num);
 
 /** Returns a new TCP_Connections object associated with the secret_key.
  *
@@ -214,7 +215,7 @@ uint32_t tcp_copy_connected_relays(TCP_Connections *tcp_c, Node_format *tcp_rela
  *
  * Returns NULL on failure.
  */
-TCP_Connections *new_tcp_connections(Mono_Time *mono_time, const uint8_t *secret_key, TCP_Proxy_Info *proxy_info);
+TCP_Connections *new_tcp_connections(Mono_Time *mono_time, const uint8_t *secret_key, const TCP_Proxy_Info *proxy_info);
 
 int kill_tcp_relay_connection(TCP_Connections *tcp_c, int tcp_connections_number);
 
diff --git a/toxcore/TCP_server.c b/toxcore/TCP_server.c
index 9b56e6ea..810958df 100644
--- a/toxcore/TCP_server.c
+++ b/toxcore/TCP_server.c
@@ -1430,7 +1430,7 @@ static void do_TCP_epoll(TCP_Server *tcp_server, const Mono_Time *mono_time)
 }
 #endif
 
-void do_TCP_server(TCP_Server *tcp_server, Mono_Time *mono_time)
+void do_TCP_server(TCP_Server *tcp_server, const Mono_Time *mono_time)
 {
 #ifdef TCP_SERVER_USE_EPOLL
     do_TCP_epoll(tcp_server, mono_time);
diff --git a/toxcore/TCP_server.h b/toxcore/TCP_server.h
index b9e4a671..03d71d8a 100644
--- a/toxcore/TCP_server.h
+++ b/toxcore/TCP_server.h
@@ -74,7 +74,7 @@ TCP_Server *new_TCP_server(const Logger *logger, uint8_t ipv6_enabled, uint16_t
 
 /** Run the TCP_server
  */
-void do_TCP_server(TCP_Server *tcp_server, Mono_Time *mono_time);
+void do_TCP_server(TCP_Server *tcp_server, const Mono_Time *mono_time);
 
 /** Kill the TCP server
  */
diff --git a/toxcore/friend_connection.c b/toxcore/friend_connection.c
index 00b65f34..a8c1371e 100644
--- a/toxcore/friend_connection.c
+++ b/toxcore/friend_connection.c
@@ -190,7 +190,7 @@ Friend_Conn *get_conn(const Friend_Connections *fr_c, int friendcon_id)
 /** return friendcon_id corresponding to the real public key on success.
  * return -1 on failure.
  */
-int getfriend_conn_id_pk(Friend_Connections *fr_c, const uint8_t *real_pk)
+int getfriend_conn_id_pk(const Friend_Connections *fr_c, const uint8_t *real_pk)
 {
     for (uint32_t i = 0; i < fr_c->num_cons; ++i) {
         Friend_Conn *friend_con = get_conn(fr_c, i);
@@ -622,7 +622,7 @@ static int send_ping(const Friend_Connections *fr_c, int friendcon_id)
  * return 0 on success.
  * return -1 on failure.
  */
-int friend_connection_lock(Friend_Connections *fr_c, int friendcon_id)
+int friend_connection_lock(const Friend_Connections *fr_c, int friendcon_id)
 {
     Friend_Conn *const friend_con = get_conn(fr_c, friendcon_id);
 
@@ -638,7 +638,7 @@ int friend_connection_lock(Friend_Connections *fr_c, int friendcon_id)
  * return FRIENDCONN_STATUS_CONNECTING if the friend isn't connected.
  * return FRIENDCONN_STATUS_NONE on failure.
  */
-unsigned int friend_con_connected(Friend_Connections *fr_c, int friendcon_id)
+unsigned int friend_con_connected(const Friend_Connections *fr_c, int friendcon_id)
 {
     const Friend_Conn *const friend_con = get_conn(fr_c, friendcon_id);
 
@@ -654,7 +654,7 @@ unsigned int friend_con_connected(Friend_Connections *fr_c, int friendcon_id)
  * return 0 on success.
  * return -1 on failure.
  */
-int get_friendcon_public_keys(uint8_t *real_pk, uint8_t *dht_temp_pk, Friend_Connections *fr_c, int friendcon_id)
+int get_friendcon_public_keys(uint8_t *real_pk, uint8_t *dht_temp_pk, const Friend_Connections *fr_c, int friendcon_id)
 {
     const Friend_Conn *const friend_con = get_conn(fr_c, friendcon_id);
 
@@ -686,7 +686,7 @@ void set_dht_temp_pk(Friend_Connections *fr_c, int friendcon_id, const uint8_t *
  * return 0 on success.
  * return -1 on failure
  */
-int friend_connection_callbacks(Friend_Connections *fr_c, int friendcon_id, unsigned int index,
+int friend_connection_callbacks(const Friend_Connections *fr_c, int friendcon_id, unsigned int index,
                                 fc_status_cb *status_callback,
                                 fc_data_cb *data_callback,
                                 fc_lossy_data_cb *lossy_data_callback,
@@ -724,7 +724,7 @@ void set_global_status_callback(Friend_Connections *fr_c, global_status_cb *glob
  * return crypt_connection_id on success.
  * return -1 on failure.
  */
-int friend_connection_crypt_connection_id(Friend_Connections *fr_c, int friendcon_id)
+int friend_connection_crypt_connection_id(const Friend_Connections *fr_c, int friendcon_id)
 {
     const Friend_Conn *const friend_con = get_conn(fr_c, friendcon_id);
 
diff --git a/toxcore/friend_connection.h b/toxcore/friend_connection.h
index 7ffb2f93..937f1cf7 100644
--- a/toxcore/friend_connection.h
+++ b/toxcore/friend_connection.h
@@ -53,27 +53,27 @@ Net_Crypto *friendconn_net_crypto(const Friend_Connections *fr_c);
 /** return friendcon_id corresponding to the real public key on success.
  * return -1 on failure.
  */
-int getfriend_conn_id_pk(Friend_Connections *fr_c, const uint8_t *real_pk);
+int getfriend_conn_id_pk(const Friend_Connections *fr_c, const uint8_t *real_pk);
 
 /** Increases lock_count for the connection with friendcon_id by 1.
  *
  * return 0 on success.
  * return -1 on failure.
  */
-int friend_connection_lock(Friend_Connections *fr_c, int friendcon_id);
+int friend_connection_lock(const Friend_Connections *fr_c, int friendcon_id);
 
 /** return FRIENDCONN_STATUS_CONNECTED if the friend is connected.
  * return FRIENDCONN_STATUS_CONNECTING if the friend isn't connected.
  * return FRIENDCONN_STATUS_NONE on failure.
  */
-unsigned int friend_con_connected(Friend_Connections *fr_c, int friendcon_id);
+unsigned int friend_con_connected(const Friend_Connections *fr_c, int friendcon_id);
 
 /** Copy public keys associated to friendcon_id.
  *
  * return 0 on success.
  * return -1 on failure.
  */
-int get_friendcon_public_keys(uint8_t *real_pk, uint8_t *dht_temp_pk, Friend_Connections *fr_c, int friendcon_id);
+int get_friendcon_public_keys(uint8_t *real_pk, uint8_t *dht_temp_pk, const Friend_Connections *fr_c, int friendcon_id);
 
 /** Set temp dht key for connection.
  */
@@ -101,7 +101,7 @@ void set_global_status_callback(Friend_Connections *fr_c, global_status_cb *glob
  * return 0 on success.
  * return -1 on failure
  */
-int friend_connection_callbacks(Friend_Connections *fr_c, int friendcon_id, unsigned int index,
+int friend_connection_callbacks(const Friend_Connections *fr_c, int friendcon_id, unsigned int index,
                                 fc_status_cb *status_callback,
                                 fc_data_cb *data_callback,
                                 fc_lossy_data_cb *lossy_data_callback,
@@ -112,7 +112,7 @@ int friend_connection_callbacks(Friend_Connections *fr_c, int friendcon_id, unsi
  * return crypt_connection_id on success.
  * return -1 on failure.
  */
-int friend_connection_crypt_connection_id(Friend_Connections *fr_c, int friendcon_id);
+int friend_connection_crypt_connection_id(const Friend_Connections *fr_c, int friendcon_id);
 
 /** Create a new friend connection.
  * If one to that real public key already exists, increase lock count and return it.
diff --git a/toxcore/group.c b/toxcore/group.c
index 277e982e..83af4644 100644
--- a/toxcore/group.c
+++ b/toxcore/group.c
@@ -337,7 +337,7 @@ static bool add_to_closest(Group_c *g, const uint8_t *real_pk, const uint8_t *te
     return true;
 }
 
-static bool pk_in_closest_peers(const Group_c *g, uint8_t *real_pk)
+static bool pk_in_closest_peers(const Group_c *g, const uint8_t *real_pk)
 {
     for (unsigned int i = 0; i < DESIRED_CLOSEST; ++i) {
         if (!g->closest_peers[i].entry) {
@@ -1430,7 +1430,7 @@ static unsigned int send_lossy_group_peer(Friend_Connections *fr_c, int friendco
  * return -2 if invite packet failed to send.
  * return -3 if we are not connected to the group chat.
  */
-int invite_friend(Group_Chats *g_c, uint32_t friendnumber, uint32_t groupnumber)
+int invite_friend(const Group_Chats *g_c, uint32_t friendnumber, uint32_t groupnumber)
 {
     Group_c *g = get_group_c(g_c, groupnumber);
 
@@ -1664,7 +1664,7 @@ int callback_groupchat_peer_new(const Group_Chats *g_c, uint32_t groupnumber, pe
  * return 0 on success.
  * return -1 on failure.
  */
-int callback_groupchat_peer_delete(Group_Chats *g_c, uint32_t groupnumber, peer_on_leave_cb *function)
+int callback_groupchat_peer_delete(const Group_Chats *g_c, uint32_t groupnumber, peer_on_leave_cb *function)
 {
     Group_c *g = get_group_c(g_c, groupnumber);
 
@@ -1681,7 +1681,7 @@ int callback_groupchat_peer_delete(Group_Chats *g_c, uint32_t groupnumber, peer_
  * return 0 on success.
  * return -1 on failure.
  */
-int callback_groupchat_delete(Group_Chats *g_c, uint32_t groupnumber, group_on_delete_cb *function)
+int callback_groupchat_delete(const Group_Chats *g_c, uint32_t groupnumber, group_on_delete_cb *function)
 {
     Group_c *g = get_group_c(g_c, groupnumber);
 
@@ -1712,7 +1712,7 @@ static bool group_ping_send(const Group_Chats *g_c, uint32_t groupnumber)
  * return true on success
  */
 static bool group_new_peer_send(const Group_Chats *g_c, uint32_t groupnumber, uint16_t peer_num, const uint8_t *real_pk,
-                                uint8_t *temp_pk)
+                                const uint8_t *temp_pk)
 {
     uint8_t packet[GROUP_MESSAGE_NEW_PEER_LENGTH];
 
@@ -2065,7 +2065,7 @@ static int send_packet_online(Friend_Connections *fr_c, int friendcon_id, uint16
                              sizeof(packet), 0) != -1;
 }
 
-static bool ping_groupchat(Group_Chats *g_c, uint32_t groupnumber);
+static bool ping_groupchat(const Group_Chats *g_c, uint32_t groupnumber);
 
 static int handle_packet_online(Group_Chats *g_c, int friendcon_id, const uint8_t *data, uint16_t length)
 {
@@ -3033,7 +3033,7 @@ void *group_peer_get_object(const Group_Chats *g_c, uint32_t groupnumber, uint32
 /* Interval in seconds to send ping messages */
 #define GROUP_PING_INTERVAL 20
 
-static bool ping_groupchat(Group_Chats *g_c, uint32_t groupnumber)
+static bool ping_groupchat(const Group_Chats *g_c, uint32_t groupnumber)
 {
     Group_c *g = get_group_c(g_c, groupnumber);
 
@@ -3097,7 +3097,7 @@ static void squash_connections(Group_c *g)
 
 #define MIN_EMPTY_CONNECTIONS (1 + MAX_GROUP_CONNECTIONS / 10)
 
-static uint16_t empty_connection_count(Group_c *g)
+static uint16_t empty_connection_count(const Group_c *g)
 {
     uint16_t to_clear = MIN_EMPTY_CONNECTIONS;
 
@@ -3152,7 +3152,7 @@ static void clean_connections(Group_Chats *g_c, Group_c *g)
 
 /** Send current name (set in messenger) to all online groups.
  */
-void send_name_all_groups(Group_Chats *g_c)
+void send_name_all_groups(const Group_Chats *g_c)
 {
     for (uint16_t i = 0; i < g_c->num_chats; ++i) {
         Group_c *g = get_group_c(g_c, i);
@@ -3431,7 +3431,7 @@ bool conferences_load_state_section(Group_Chats *g_c, const uint8_t *data, uint3
 
 
 /** Create new groupchat instance. */
-Group_Chats *new_groupchats(Mono_Time *mono_time, Messenger *m)
+Group_Chats *new_groupchats(const Mono_Time *mono_time, Messenger *m)
 {
     if (!m) {
         return nullptr;
diff --git a/toxcore/group.h b/toxcore/group.h
index 89b084f9..1797525b 100644
--- a/toxcore/group.h
+++ b/toxcore/group.h
@@ -286,7 +286,7 @@ int group_set_max_frozen(const Group_Chats *g_c, uint32_t groupnumber, uint32_t
  * return -2 if invite packet failed to send.
  * return -3 if we are not connected to the group chat.
  */
-int invite_friend(Group_Chats *g_c, uint32_t friendnumber, uint32_t groupnumber);
+int invite_friend(const Group_Chats *g_c, uint32_t friendnumber, uint32_t groupnumber);
 
 /** Join a group (we need to have been invited first.)
  *
@@ -395,7 +395,7 @@ int32_t conference_by_id(const Group_Chats *g_c, const uint8_t *id);
 
 /** Send current name (set in messenger) to all online groups.
  */
-void send_name_all_groups(Group_Chats *g_c);
+void send_name_all_groups(const Group_Chats *g_c);
 
 /** Set the object that is tied to the group chat.
  *
@@ -437,14 +437,14 @@ int callback_groupchat_peer_new(const Group_Chats *g_c, uint32_t groupnumber, pe
  * return 0 on success.
  * return -1 on failure.
  */
-int callback_groupchat_peer_delete(Group_Chats *g_c, uint32_t groupnumber, peer_on_leave_cb *function);
+int callback_groupchat_peer_delete(const Group_Chats *g_c, uint32_t groupnumber, peer_on_leave_cb *function);
 
 /** Set a function to be called when the group chat is deleted.
  *
  * return 0 on success.
  * return -1 on failure.
  */
-int callback_groupchat_delete(Group_Chats *g_c, uint32_t groupnumber, group_on_delete_cb *function);
+int callback_groupchat_delete(const Group_Chats *g_c, uint32_t groupnumber, group_on_delete_cb *function);
 
 /** Return size of the conferences data (for saving). */
 uint32_t conferences_size(const Group_Chats *g_c);
@@ -465,7 +465,7 @@ bool conferences_load_state_section(Group_Chats *g_c, const uint8_t *data, uint3
                                     State_Load_Status *status);
 
 /** Create new groupchat instance. */
-Group_Chats *new_groupchats(Mono_Time *mono_time, Messenger *m);
+Group_Chats *new_groupchats(const Mono_Time *mono_time, Messenger *m);
 
 /** main groupchats loop. */
 void do_groupchats(Group_Chats *g_c, void *userdata);
diff --git a/toxcore/net_crypto.c b/toxcore/net_crypto.c
index 16a4a175..c45cda2e 100644
--- a/toxcore/net_crypto.c
+++ b/toxcore/net_crypto.c
@@ -207,8 +207,8 @@ static bool crypt_connection_id_is_valid(const Net_Crypto *c, int crypt_connecti
  * return -1 on failure.
  * return COOKIE_REQUEST_LENGTH on success.
  */
-static int create_cookie_request(const Net_Crypto *c, uint8_t *packet, uint8_t *dht_public_key, uint64_t number,
-                                 uint8_t *shared_key)
+static int create_cookie_request(const Net_Crypto *c, uint8_t *packet, const uint8_t *dht_public_key,
+                                 uint64_t number, uint8_t *shared_key)
 {
     uint8_t plain[COOKIE_REQUEST_PLAIN_LENGTH];
     uint8_t padding[CRYPTO_PUBLIC_KEY_SIZE] = {0};
@@ -601,7 +601,7 @@ static int add_ip_port_connection(Net_Crypto *c, int crypt_connection_id, IP_Por
  * return IP_Port with family 0 on failure.
  * return IP_Port on success.
  */
-static IP_Port return_ip_port_connection(Net_Crypto *c, int crypt_connection_id)
+static IP_Port return_ip_port_connection(const Net_Crypto *c, int crypt_connection_id)
 {
     const IP_Port empty = {0};
 
@@ -1988,7 +1988,7 @@ static int handle_new_connection_handshake(Net_Crypto *c, IP_Port source, const
  * return -1 on failure.
  * return connection id on success.
  */
-int accept_crypto_connection(Net_Crypto *c, New_Connection *n_c)
+int accept_crypto_connection(Net_Crypto *c, const New_Connection *n_c)
 {
     if (getcryptconnection_id(c, n_c->public_key) != -1) {
         return -1;
@@ -2361,7 +2361,7 @@ int connection_data_handler(const Net_Crypto *c, int crypt_connection_id,
  * return -1 on failure.
  * return 0 on success.
  */
-int connection_lossy_data_handler(Net_Crypto *c, int crypt_connection_id,
+int connection_lossy_data_handler(const Net_Crypto *c, int crypt_connection_id,
                                   connection_lossy_data_cb *connection_lossy_data_callback,
                                   void *object, int id)
 {
@@ -2388,7 +2388,7 @@ int connection_lossy_data_handler(Net_Crypto *c, int crypt_connection_id,
  * return -1 on failure.
  * return 0 on success.
  */
-int nc_dht_pk_callback(Net_Crypto *c, int crypt_connection_id, dht_pk_cb *function, void *object, uint32_t number)
+int nc_dht_pk_callback(const Net_Crypto *c, int crypt_connection_id, dht_pk_cb *function, void *object, uint32_t number)
 {
     Crypto_Connection *conn = get_crypto_connection(c, crypt_connection_id);
 
@@ -2811,7 +2811,7 @@ int64_t write_cryptpacket(Net_Crypto *c, int crypt_connection_id, const uint8_t
  * It CANNOT be simplified to `packet_number < buffer_start`, as it will fail
  * when `buffer_end < buffer_start`.
  */
-int cryptpacket_received(Net_Crypto *c, int crypt_connection_id, uint32_t packet_number)
+int cryptpacket_received(const Net_Crypto *c, int crypt_connection_id, uint32_t packet_number)
 {
     Crypto_Connection *conn = get_crypto_connection(c, crypt_connection_id);
 
diff --git a/toxcore/net_crypto.h b/toxcore/net_crypto.h
index 452066a7..da9884bb 100644
--- a/toxcore/net_crypto.h
+++ b/toxcore/net_crypto.h
@@ -144,7 +144,7 @@ void new_connection_handler(Net_Crypto *c, new_connection_cb *new_connection_cal
  * return -1 on failure.
  * return connection id on success.
  */
-int accept_crypto_connection(Net_Crypto *c, New_Connection *n_c);
+int accept_crypto_connection(Net_Crypto *c, const New_Connection *n_c);
 
 /* Create a crypto connection.
  * If one to that real public key already exists, return it.
@@ -196,7 +196,7 @@ int connection_data_handler(const Net_Crypto *c, int crypt_connection_id,
  * return -1 on failure.
  * return 0 on success.
  */
-int connection_lossy_data_handler(Net_Crypto *c, int crypt_connection_id,
+int connection_lossy_data_handler(const Net_Crypto *c, int crypt_connection_id,
                                   connection_lossy_data_cb *connection_lossy_data_callback, void *object, int id);
 
 /* Set the function for this friend that will be callbacked with object and number if
@@ -209,7 +209,8 @@ int connection_lossy_data_handler(Net_Crypto *c, int crypt_connection_id,
  * return -1 on failure.
  * return 0 on success.
  */
-int nc_dht_pk_callback(Net_Crypto *c, int crypt_connection_id, dht_pk_cb *function, void *object, uint32_t number);
+int nc_dht_pk_callback(const Net_Crypto *c, int crypt_connection_id, dht_pk_cb *function, void *object,
+                       uint32_t number);
 
 /* returns the number of packet slots left in the sendbuffer.
  * return 0 if failure.
@@ -240,7 +241,7 @@ int64_t write_cryptpacket(Net_Crypto *c, int crypt_connection_id, const uint8_t
  * return -1 on failure.
  * return 0 on success.
  */
-int cryptpacket_received(Net_Crypto *c, int crypt_connection_id, uint32_t packet_number);
+int cryptpacket_received(const Net_Crypto *c, int crypt_connection_id, uint32_t packet_number);
 
 /* Sends a lossy cryptopacket.
  *
diff --git a/toxcore/onion_client.c b/toxcore/onion_client.c
index 51837a09..1f940c30 100644
--- a/toxcore/onion_client.c
+++ b/toxcore/onion_client.c
@@ -326,7 +326,7 @@ static int is_path_used(const Mono_Time *mono_time, const Onion_Client_Paths *on
 }
 
 /** is path timed out */
-static bool path_timed_out(const Mono_Time *mono_time, Onion_Client_Paths *onion_paths, uint32_t pathnum)
+static bool path_timed_out(const Mono_Time *mono_time, const Onion_Client_Paths *onion_paths, uint32_t pathnum)
 {
     pathnum = pathnum % NUMBER_ONION_PATHS;
 
@@ -737,7 +737,7 @@ static int client_add_to_list(Onion_Client *onion_c, uint32_t num, const uint8_t
     return 0;
 }
 
-static int good_to_ping(Mono_Time *mono_time, Last_Pinged *last_pinged, uint8_t *last_pinged_index,
+static int good_to_ping(const Mono_Time *mono_time, Last_Pinged *last_pinged, uint8_t *last_pinged_index,
                         const uint8_t *public_key)
 {
     for (unsigned int i = 0; i < MAX_STORED_PINGED_NODES; ++i) {
diff --git a/toxcore/ping.c b/toxcore/ping.c
index 0eb52745..18994ab8 100644
--- a/toxcore/ping.c
+++ b/toxcore/ping.c
@@ -90,8 +90,8 @@ void ping_send_request(Ping *ping, IP_Port ipp, const uint8_t *public_key)
     sendpacket(dht_get_net(ping->dht), ipp, pk, sizeof(pk));
 }
 
-static int ping_send_response(Ping *ping, IP_Port ipp, const uint8_t *public_key, uint64_t ping_id,
-                              uint8_t *shared_encryption_key)
+static int ping_send_response(const Ping *ping, IP_Port ipp, const uint8_t *public_key,
+                              uint64_t ping_id, const uint8_t *shared_encryption_key)
 {
     uint8_t pk[DHT_PING_SIZE];