tildefriends/src/ssb.c

#include "ssb.h"

#include "log.h"
#include "mem.h"
#include "ssb.connections.h"
#include "ssb.db.h"
#include "ssb.rpc.h"
#include "trace.h"
#include "util.js.h"

#include "ares.h"
#include "quickjs.h"
#include "sodium/crypto_auth.h"
#include "sodium/crypto_box.h"
#include "sodium/crypto_hash_sha256.h"
#include "sodium/crypto_scalarmult.h"
#include "sodium/crypto_scalarmult_curve25519.h"
#include "sodium/crypto_secretbox.h"
#include "sodium/crypto_sign.h"
#include "sodium/utils.h"
#include "sqlite3.h"
#include "uv.h"

#if !defined(_WIN32)
#include <arpa/nameser.h>
#endif

#include <assert.h>
#include <stdbool.h>
#include <stdio.h>
#include <string.h>
#include <time.h>

#if !defined(_countof)
#define _countof(a) ((int)(sizeof((a)) / sizeof(*(a))))
#endif

#define GREEN "\e[1;32m"
#define MAGENTA "\e[1;35m"
#define CYAN "\e[1;36m"
#define RESET "\e[0m"

#define PRE_CALLBACK(ssb, cb) uint64_t pre_callback_hrtime_ns = _tf_ssb_callback_pre(ssb)
#define POST_CALLBACK(ssb, cb) _tf_ssb_callback_post(ssb, cb, pre_callback_hrtime_ns)

static_assert(k_id_base64_len == sodium_base64_ENCODED_LEN(9 + crypto_box_PUBLICKEYBYTES, sodium_base64_VARIANT_ORIGINAL), "k_id_base64_len");
static_assert(k_id_bin_len == crypto_box_PUBLICKEYBYTES, "k_id_bin_len");
static_assert(k_blob_id_len == (sodium_base64_ENCODED_LEN(crypto_hash_sha256_BYTES, sodium_base64_VARIANT_ORIGINAL) + 8), "k_blob_id_len");

const char* k_ssb_network_string = "d4a1cb88a66f02f8db635ce26441cc5dac1b08420ceaac230839b755845a9ffb";

const char* k_ssb_type_names[] = {
	"binary",
	"utf8",
	"json",
	"unknown",
};

typedef enum
{
	k_tf_ssb_state_invalid,
	k_tf_ssb_state_connected,
	k_tf_ssb_state_sent_hello,
	k_tf_ssb_state_sent_identity,
	k_tf_ssb_state_verified,

	k_tf_ssb_state_server_wait_hello,
	k_tf_ssb_state_server_wait_client_identity,
	k_tf_ssb_state_server_verified,

	k_tf_ssb_state_closing,
} tf_ssb_state_t;

enum
{
	k_connections_changed_callbacks_max = 8,
	k_tf_ssb_rpc_message_body_length_max = 1 * 1024 * 1024,
	k_debug_close_message_count = 256,
	k_debug_close_connection_count = 32,
};

typedef struct _tf_ssb_broadcast_t tf_ssb_broadcast_t;
typedef struct _tf_ssb_connection_t tf_ssb_connection_t;
typedef struct _tf_ssb_request_t tf_ssb_request_t;

typedef struct _tf_ssb_debug_message_t
{
	bool outgoing;
	int flags;
	int32_t request_number;
	time_t timestamp;
	size_t size;
	uint8_t data[];
} tf_ssb_debug_message_t;

typedef struct _tf_ssb_debug_close_t
{
	char id[k_id_base64_len];
	char tunnel[k_id_base64_len];
	char reason[128];
	tf_ssb_debug_message_t* messages[k_debug_close_message_count];
} tf_ssb_debug_close_t;

typedef struct _tf_ssb_request_t
{
	char name[256];
	tf_ssb_rpc_callback_t* callback;
	tf_ssb_callback_cleanup_t* cleanup;
	void* user_data;
	tf_ssb_connection_t* dependent_connection;
	int32_t request_number;
} tf_ssb_request_t;

typedef struct _tf_ssb_broadcast_t
{
	tf_ssb_broadcast_t* next;
	time_t ctime;
	time_t mtime;
	char host[256];
	struct sockaddr_in addr;
	tf_ssb_connection_t* tunnel_connection;
	uint8_t pub[crypto_sign_PUBLICKEYBYTES];
} tf_ssb_broadcast_t;

typedef struct _tf_ssb_rpc_callback_node_t tf_ssb_rpc_callback_node_t;
typedef struct _tf_ssb_rpc_callback_node_t
{
	const char** name;
	const char* flattened_name;
	tf_ssb_rpc_callback_t* callback;
	tf_ssb_callback_cleanup_t* cleanup;
	void* user_data;
	tf_ssb_rpc_callback_node_t* next;
} tf_ssb_rpc_callback_node_t;

typedef struct _tf_ssb_connections_changed_callback_node_t tf_ssb_connections_changed_callback_node_t;
typedef struct _tf_ssb_connections_changed_callback_node_t
{
	tf_ssb_connections_changed_callback_t* callback;
	tf_ssb_callback_cleanup_t* cleanup;
	void* user_data;
	tf_ssb_connections_changed_callback_node_t* next;
} tf_ssb_connections_changed_callback_node_t;

typedef struct _tf_ssb_message_added_callback_node_t tf_ssb_message_added_callback_node_t;
typedef struct _tf_ssb_message_added_callback_node_t
{
	tf_ssb_message_added_callback_t* callback;
	tf_ssb_callback_cleanup_t* cleanup;
	void* user_data;
	tf_ssb_message_added_callback_node_t* next;
} tf_ssb_message_added_callback_node_t;

typedef struct _tf_ssb_blob_want_added_callback_node_t tf_ssb_blob_want_added_callback_node_t;
typedef struct _tf_ssb_blob_want_added_callback_node_t
{
	tf_ssb_blob_want_added_callback_t* callback;
	tf_ssb_callback_cleanup_t* cleanup;
	void* user_data;
	tf_ssb_blob_want_added_callback_node_t* next;
} tf_ssb_blob_want_added_callback_node_t;

typedef struct _tf_ssb_broadcasts_changed_callback_node_t tf_ssb_broadcasts_changed_callback_node_t;
typedef struct _tf_ssb_broadcasts_changed_callback_node_t
{
	tf_ssb_broadcasts_changed_callback_t* callback;
	tf_ssb_callback_cleanup_t* cleanup;
	void* user_data;
	tf_ssb_broadcasts_changed_callback_node_t* next;
} tf_ssb_broadcasts_changed_callback_node_t;

typedef struct _tf_thread_work_time_t
{
	int64_t thread_id;
	uint64_t hrtime;
} tf_thread_work_time_t;

typedef struct _tf_ssb_timer_t
{
	tf_ssb_t* ssb;
	uv_timer_t timer;
	void (*callback)(tf_ssb_t* ssb, void* user_data);
	void* user_data;
} tf_ssb_timer_t;

typedef struct _tf_ssb_t
{
	bool own_context;
	JSRuntime* runtime;
	JSContext* context;

	tf_trace_t* trace;

	const char* db_path;

	uv_mutex_t db_readers_lock;
	uv_mutex_t db_writer_lock;
	sqlite3* db_writer;
	sqlite3** db_readers;
	int db_readers_count;

	uv_loop_t own_loop;
	uv_loop_t* loop;
	uv_udp_t broadcast_listener;
	uv_udp_t broadcast_sender;
	uv_timer_t broadcast_cleanup_timer;
	uv_timer_t broadcast_timer;
	uv_timer_t trace_timer;
	uv_tcp_t server;

	uint8_t network_key[32];

	uint8_t pub[crypto_sign_PUBLICKEYBYTES];
	uint8_t priv[crypto_sign_SECRETKEYBYTES];

	bool verbose;
	bool store_debug_messages;
	bool shutting_down;

	int messages_stored;
	int blobs_stored;
	int rpc_in;
	int rpc_out;

	tf_ssb_connection_t* connections;
	int connections_count;
	int connection_ref_count;
	int request_count;

	tf_ssb_connections_t* connections_tracker;

	tf_ssb_broadcast_t* broadcasts;
	int broadcasts_count;

	tf_ssb_rpc_callback_node_t* rpc;
	int rpc_count;

	tf_ssb_connections_changed_callback_node_t* connections_changed;
	int connections_changed_count;

	tf_ssb_message_added_callback_node_t* message_added;
	int message_added_count;

	tf_ssb_blob_want_added_callback_node_t* blob_want_added;
	int blob_want_added_count;

	tf_ssb_broadcasts_changed_callback_node_t* broadcasts_changed;
	int broadcasts_changed_count;

	tf_ssb_debug_close_t debug_close[k_debug_close_connection_count];

	int32_t thread_busy_count;
	int32_t thread_busy_max;

	void (*hitch_callback)(const char* name, uint64_t duration, void* user_data);
	void* hitch_user_data;

	tf_ssb_store_queue_t store_queue;
	int ref_count;

	uv_thread_t thread_self;
	bool is_room;
	char* room_name;
	char seeds_host[256];

	tf_ssb_timer_t** timers;
	int timers_count;
} tf_ssb_t;

typedef struct _tf_ssb_connection_message_request_t
{
	int32_t request_number;
	char author[k_id_base64_len];
	bool keys;
} tf_ssb_connection_message_request_t;

typedef struct _tf_ssb_connection_scheduled_t
{
	tf_ssb_scheduled_callback_t* callback;
	void* user_data;
} tf_ssb_connection_scheduled_t;

typedef struct _tf_ssb_connection_t
{
	tf_ssb_t* ssb;
	uv_tcp_t tcp;
	uv_connect_t connect;
	uv_async_t async;
	bool closing;

	tf_ssb_connection_t* tunnel_connection;
	int32_t tunnel_request_number;

	tf_ssb_blob_wants_t blob_wants;
	bool sent_clock;
	int32_t ebt_request_number;

	JSValue object;

	char name[32];

	char host[256];
	int port;

	tf_ssb_state_t state;
	bool is_attendant;
	int32_t attendant_request_number;

	uint8_t epub[crypto_box_PUBLICKEYBYTES];
	uint8_t epriv[crypto_box_SECRETKEYBYTES];

	uint8_t serverpub[crypto_box_PUBLICKEYBYTES];
	uint8_t serverepub[crypto_box_PUBLICKEYBYTES];

	uint8_t detached_signature_A[crypto_sign_BYTES];

	uint8_t s_to_c_box_key[crypto_hash_sha256_BYTES];
	uint8_t c_to_s_box_key[crypto_hash_sha256_BYTES];

	uint8_t recv_buffer[128 * 1024];
	size_t recv_size;

	uint8_t nonce[crypto_secretbox_NONCEBYTES];
	uint8_t send_nonce[crypto_secretbox_NONCEBYTES];

	uint16_t body_len;
	uint8_t body_auth_tag[16];

	uint8_t rpc_recv_buffer[8 * 1024 * 1024];
	uint8_t pad;
	size_t rpc_recv_size;

	uint8_t box_stream_buf[16 + k_tf_ssb_rpc_message_body_length_max];
	uint8_t secretbox_buf[k_tf_ssb_rpc_message_body_length_max];

	uint32_t send_request_number;

	tf_ssb_connection_t* next;
	tf_ssb_request_t* requests;
	int requests_count;
	const char* destroy_reason;

	tf_ssb_connection_message_request_t* message_requests;
	int message_requests_count;

	tf_ssb_connection_scheduled_t* scheduled;
	int scheduled_count;

	tf_ssb_debug_message_t* debug_messages[k_debug_close_message_count];
	int ref_count;

	int read_back_pressure;
	int active_write_count;
} tf_ssb_connection_t;

static JSClassID _connection_class_id;
static int s_connection_index;
static int s_tunnel_index;

static void _tf_ssb_add_broadcast(tf_ssb_t* ssb, const tf_ssb_broadcast_t* broadcast);
static void _tf_ssb_connection_client_send_hello(tf_ssb_connection_t* connection);
static void _tf_ssb_connection_close(tf_ssb_connection_t* connection, const char* reason);
static void _tf_ssb_connection_destroy(tf_ssb_connection_t* connection, const char* reason);
static void _tf_ssb_connection_finalizer(JSRuntime* runtime, JSValue value);
static void _tf_ssb_connection_on_close(uv_handle_t* handle);
static void _tf_ssb_nonce_inc(uint8_t* nonce);
static void _tf_ssb_notify_connections_changed(tf_ssb_t* ssb, tf_ssb_change_t change, tf_ssb_connection_t* connection);
static bool _tf_ssb_parse_broadcast(const char* in_broadcast, tf_ssb_broadcast_t* out_broadcast);
static void _tf_ssb_start_update_settings(tf_ssb_t* ssb);
static void _tf_ssb_update_settings(tf_ssb_t* ssb);
static void _tf_ssb_write(tf_ssb_connection_t* connection, void* data, size_t size);

static void _tf_ssb_add_debug_close(tf_ssb_t* ssb, tf_ssb_connection_t* connection, const char* reason)
{
	if (!ssb->store_debug_messages)
	{
		return;
	}

	for (int i = 0; i < k_debug_close_message_count; i++)
	{
		tf_free(ssb->debug_close[k_debug_close_connection_count - 1].messages[i]);
	}
	for (int i = k_debug_close_connection_count - 1; i > 0; i--)
	{
		ssb->debug_close[i] = ssb->debug_close[i - 1];
	}

	tf_ssb_id_bin_to_str(ssb->debug_close[0].id, sizeof(ssb->debug_close[0].id), connection->serverpub);
	if (connection->tunnel_connection)
	{
		tf_ssb_id_bin_to_str(ssb->debug_close[0].tunnel, sizeof(ssb->debug_close[0].tunnel), connection->tunnel_connection->serverpub);
	}
	else
	{
		memset(ssb->debug_close[0].tunnel, 0, sizeof(ssb->debug_close[0].tunnel));
	}
	memcpy(ssb->debug_close[0].messages, connection->debug_messages, sizeof(connection->debug_messages));
	memset(connection->debug_messages, 0, sizeof(connection->debug_messages));
	snprintf(ssb->debug_close[0].reason, sizeof(ssb->debug_close[0].reason), "%s", reason);
}

static void _tf_ssb_connection_add_debug_message(tf_ssb_connection_t* connection, bool outgoing, int flags, int32_t request_number, const uint8_t* data, size_t size)
{
	if (!connection->ssb->store_debug_messages)
	{
		return;
	}

	if (connection->debug_messages[k_debug_close_message_count - 1])
	{
		tf_free(connection->debug_messages[k_debug_close_message_count - 1]);
	}
	for (int i = k_debug_close_message_count - 1; i > 0; i--)
	{
		connection->debug_messages[i] = connection->debug_messages[i - 1];
	}
	tf_ssb_debug_message_t* message = tf_malloc(sizeof(tf_ssb_debug_message_t) + size);
	*message = (tf_ssb_debug_message_t) {
		.outgoing = outgoing,
		.flags = flags,
		.request_number = request_number,
		.timestamp = time(NULL),
		.size = size,
	};
	memcpy(message + 1, data, size);
	connection->debug_messages[0] = message;
}

static void _tf_ssb_connection_send_close(tf_ssb_connection_t* connection)
{
	uint8_t message_enc[34];

	uint8_t nonce1[crypto_secretbox_NONCEBYTES];
	memcpy(nonce1, connection->send_nonce, sizeof(nonce1));
	_tf_ssb_nonce_inc(connection->send_nonce);

	uint8_t header[18] = { 0 };
	if (crypto_secretbox_easy(message_enc, header, sizeof(header), nonce1, connection->c_to_s_box_key) == 0)
	{
		_tf_ssb_write(connection, message_enc, sizeof(message_enc));
	}
	_tf_ssb_connection_close(connection, "crypto_secretbox_easy close message");
}

static void _tf_ssb_connection_close(tf_ssb_connection_t* connection, const char* reason)
{
	if (connection->state == k_tf_ssb_state_closing)
	{
		return;
	}
	else if (connection->state == k_tf_ssb_state_verified || connection->state == k_tf_ssb_state_server_verified)
	{
		tf_printf("Connection %s %p is closing: %s.\n", connection->name, connection, reason);
		_tf_ssb_add_debug_close(connection->ssb, connection, reason);
		connection->state = k_tf_ssb_state_closing;
		_tf_ssb_connection_send_close(connection);
	}
	_tf_ssb_connection_destroy(connection, reason);
}

static void _tf_ssb_connection_on_tcp_alloc(uv_handle_t* handle, size_t suggested_size, uv_buf_t* buf)
{
	tf_ssb_connection_t* connection = handle->data;
	size_t malloc_size = sizeof(connection->recv_buffer) - connection->recv_size;
	buf->base = malloc_size ? tf_malloc(malloc_size) : NULL;
	buf->len = malloc_size;
}

static void _tf_ssb_connection_on_write(uv_write_t* req, int status)
{
	tf_ssb_connection_t* connection = req->data;
	tf_ssb_connection_adjust_write_count(connection, -1);
	if (status)
	{
		char buffer[256];
		snprintf(buffer, sizeof(buffer), "write failed asynchronously: %s", uv_strerror(status));
		_tf_ssb_connection_close(connection, buffer);
	}
	tf_free(req);
}

static void _tf_ssb_write(tf_ssb_connection_t* connection, void* data, size_t size)
{
	if (connection->tcp.data)
	{
		uv_write_t* write = tf_malloc(sizeof(uv_write_t) + size);
		*write = (uv_write_t) { .data = connection };
		memcpy(write + 1, data, size);
		tf_ssb_connection_adjust_write_count(connection, 1);
		int result = uv_write(write, (uv_stream_t*)&connection->tcp, &(uv_buf_t) { .base = (char*)(write + 1), .len = size }, 1, _tf_ssb_connection_on_write);
		if (result)
		{
			tf_ssb_connection_adjust_write_count(connection, -1);
			_tf_ssb_connection_close(connection, "write failed");
			tf_free(write);
		}
	}
	else if (connection->tunnel_connection)
	{
		tf_ssb_connection_rpc_send(
			connection->tunnel_connection, k_ssb_rpc_flag_binary | k_ssb_rpc_flag_stream, -connection->tunnel_request_number, NULL, data, size, NULL, NULL, NULL);
	}
}

static void _tf_ssb_connection_send_identity(tf_ssb_connection_t* connection, uint8_t* hmac, uint8_t* pubkey)
{
	memcpy(connection->serverepub, pubkey, sizeof(connection->serverepub));
	if (crypto_auth_hmacsha512256_verify(hmac, connection->serverepub, 32, connection->ssb->network_key) != 0)
	{
		_tf_ssb_connection_close(connection, "invalid server hello");
		return;
	}

	uint8_t shared_secret_ab[crypto_scalarmult_curve25519_SCALARBYTES];
	if (crypto_scalarmult_curve25519(shared_secret_ab, connection->epriv, connection->serverepub) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to compute shared_secret_ab as client");
		return;
	}

	uint8_t servercurvepub[crypto_scalarmult_curve25519_SCALARBYTES];
	if (crypto_sign_ed25519_pk_to_curve25519(servercurvepub, connection->serverpub) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to compute key to curve25519 as client");
		return;
	}

	uint8_t shared_secret_aB[crypto_scalarmult_curve25519_SCALARBYTES];
	if (crypto_scalarmult_curve25519(shared_secret_aB, connection->epriv, servercurvepub) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to compute shared_secret_aB as client");
		return;
	}

	uint8_t hash[crypto_hash_sha256_BYTES];
	crypto_hash_sha256(hash, shared_secret_ab, sizeof(shared_secret_ab));

	uint8_t msg[sizeof(connection->ssb->network_key) + sizeof(connection->serverpub) + crypto_hash_sha256_BYTES];
	memcpy(msg, connection->ssb->network_key, sizeof(connection->ssb->network_key));
	memcpy(msg + sizeof(connection->ssb->network_key), connection->serverpub, sizeof(connection->serverpub));
	memcpy(msg + sizeof(connection->ssb->network_key) + sizeof(connection->serverpub), hash, sizeof(hash));

	unsigned long long siglen;
	if (crypto_sign_detached(connection->detached_signature_A, &siglen, msg, sizeof(msg), connection->ssb->priv) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to compute detached_signature_A as client");
		return;
	}

	uint8_t tosend[crypto_sign_BYTES + sizeof(connection->ssb->pub)];
	memcpy(tosend, connection->detached_signature_A, sizeof(connection->detached_signature_A));
	memcpy(tosend + sizeof(connection->detached_signature_A), connection->ssb->pub, sizeof(connection->ssb->pub));
	uint8_t nonce[crypto_secretbox_NONCEBYTES] = { 0 };

	uint8_t tohash[sizeof(connection->ssb->network_key) + sizeof(shared_secret_ab) + sizeof(shared_secret_aB)];
	memcpy(tohash, connection->ssb->network_key, sizeof(connection->ssb->network_key));
	memcpy(tohash + sizeof(connection->ssb->network_key), shared_secret_ab, sizeof(shared_secret_ab));
	memcpy(tohash + sizeof(connection->ssb->network_key) + sizeof(shared_secret_ab), shared_secret_aB, sizeof(shared_secret_aB));
	uint8_t hash2[crypto_hash_sha256_BYTES];
	crypto_hash_sha256(hash2, tohash, sizeof(tohash));

	uint8_t c[crypto_secretbox_MACBYTES + sizeof(tosend)];
	if (crypto_secretbox_easy(c, tosend, sizeof(tosend), nonce, hash2) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to create initial secretbox as client");
		return;
	}

	static_assert(sizeof(c) == 112, "client send size");
	_tf_ssb_write(connection, c, sizeof(c));
	connection->state = k_tf_ssb_state_sent_identity;
}

static void _tf_ssb_nonce_inc(uint8_t* nonce)
{
	int i = 23;
	while (++nonce[i] == 0 && i > 0)
	{
		i--;
	}
}

static void _tf_ssb_connection_box_stream_send(tf_ssb_connection_t* connection, const uint8_t* message, size_t size)
{
	const size_t k_send_max = 4096;
	for (size_t offset = 0; offset < size; offset += k_send_max)
	{
		size_t send_size = size - offset > k_send_max ? k_send_max : size - offset;
		uint8_t* message_enc = tf_malloc(send_size + 34);

		uint8_t nonce1[crypto_secretbox_NONCEBYTES];
		memcpy(nonce1, connection->send_nonce, sizeof(nonce1));
		_tf_ssb_nonce_inc(connection->send_nonce);
		uint8_t nonce2[crypto_secretbox_NONCEBYTES];
		memcpy(nonce2, connection->send_nonce, sizeof(nonce2));
		_tf_ssb_nonce_inc(connection->send_nonce);

		if (crypto_secretbox_easy(message_enc + 34 - 16, message + offset, send_size, nonce2, connection->c_to_s_box_key) != 0)
		{
			_tf_ssb_connection_close(connection, "unable to secretbox message");
			tf_free(message_enc);
			return;
		}

		uint8_t header[18];
		*(uint16_t*)header = htons((uint16_t)send_size);
		memcpy(header + sizeof(uint16_t), message_enc + 34 - 16, 16);
		if (crypto_secretbox_easy(message_enc, header, sizeof(header), nonce1, connection->c_to_s_box_key) != 0)
		{
			_tf_ssb_connection_close(connection, "unable to secretbox header");
			tf_free(message_enc);
			return;
		}

		_tf_ssb_write(connection, message_enc, send_size + 34);
		tf_free(message_enc);
	}
}

static void _tf_ssb_connection_dispatch_scheduled(tf_ssb_connection_t* connection)
{
	while ((connection->active_write_count == 0 || connection->closing) && connection->scheduled_count && connection->scheduled)
	{
		tf_ssb_connection_scheduled_t scheduled = connection->scheduled[0];
		memmove(connection->scheduled, connection->scheduled + 1, sizeof(tf_ssb_connection_scheduled_t) * (connection->scheduled_count - 1));
		connection->scheduled_count--;
		tf_trace_begin(connection->ssb->trace, "scheduled callback");
		scheduled.callback(connection, scheduled.user_data);
		tf_trace_end(connection->ssb->trace);
	}
}

void tf_ssb_connection_schedule_idle(tf_ssb_connection_t* connection, tf_ssb_scheduled_callback_t* callback, void* user_data)
{
	connection->scheduled = tf_resize_vec(connection->scheduled, sizeof(tf_ssb_connection_scheduled_t) * (connection->scheduled_count + 1));
	connection->scheduled[connection->scheduled_count++] = (tf_ssb_connection_scheduled_t) {
		.callback = callback,
		.user_data = user_data,
	};
	_tf_ssb_connection_dispatch_scheduled(connection);
}

static int _request_compare(const void* a, const void* b)
{
	int32_t ai = *(const int32_t*)a;
	const tf_ssb_request_t* br = (const tf_ssb_request_t*)b;
	return ai < br->request_number ? -1 : br->request_number < ai ? 1 : 0;
}

static bool _tf_ssb_connection_get_request_callback(tf_ssb_connection_t* connection, int32_t request_number, tf_ssb_rpc_callback_t** out_callback, void** out_user_data)
{
	if (!connection->requests)
	{
		return false;
	}
	tf_ssb_request_t* request = bsearch(&request_number, connection->requests, connection->requests_count, sizeof(tf_ssb_request_t), _request_compare);
	if (request)
	{
		if (out_callback)
		{
			*out_callback = request->callback;
		}
		if (out_user_data)
		{
			*out_user_data = request->user_data;
		}
		return true;
	}
	return false;
}

void tf_ssb_connection_add_request(tf_ssb_connection_t* connection, int32_t request_number, const char* name, tf_ssb_rpc_callback_t* callback, tf_ssb_callback_cleanup_t* cleanup,
	void* user_data, tf_ssb_connection_t* dependent_connection)
{
	tf_ssb_request_t* existing =
		connection->requests_count ? bsearch(&request_number, connection->requests, connection->requests_count, sizeof(tf_ssb_request_t), _request_compare) : NULL;
	if (existing)
	{
		assert(!existing->callback);
		assert(!existing->cleanup);
		assert(!existing->user_data);
		assert(!existing->dependent_connection);
		existing->callback = callback;
		existing->cleanup = cleanup;
		existing->user_data = user_data;
		existing->dependent_connection = dependent_connection;
	}
	else
	{
		tf_ssb_connection_remove_request(connection, request_number);
		tf_ssb_request_t request = {
			.request_number = request_number,
			.callback = callback,
			.cleanup = cleanup,
			.user_data = user_data,
			.dependent_connection = dependent_connection,
		};
		snprintf(request.name, sizeof(request.name), "%s", name);
		int index = tf_util_insert_index(&request_number, connection->requests, connection->requests_count, sizeof(tf_ssb_request_t), _request_compare);
		connection->requests = tf_resize_vec(connection->requests, sizeof(tf_ssb_request_t) * (connection->requests_count + 1));
		if (connection->requests_count - index)
		{
			memmove(connection->requests + index + 1, connection->requests + index, sizeof(tf_ssb_request_t) * (connection->requests_count - index));
		}
		connection->requests[index] = request;
		connection->requests_count++;

		connection->ssb->request_count++;
	}
	_tf_ssb_notify_connections_changed(connection->ssb, k_tf_ssb_change_update, connection);
}

static int _message_request_compare(const void* a, const void* b)
{
	const char* author = a;
	const tf_ssb_connection_message_request_t* rb = b;
	return strcmp(author, rb->author);
}

void tf_ssb_connection_add_new_message_request(tf_ssb_connection_t* connection, const char* author, int32_t request_number, bool keys)
{
	int index =
		tf_util_insert_index(author, connection->message_requests, connection->message_requests_count, sizeof(tf_ssb_connection_message_request_t), _message_request_compare);
	if (index < connection->message_requests_count && strcmp(author, connection->message_requests[index].author) == 0)
	{
		connection->message_requests[index].request_number = request_number;
		connection->message_requests[index].keys = keys;
		return;
	}
	connection->message_requests = tf_resize_vec(connection->message_requests, sizeof(tf_ssb_connection_message_request_t) * (connection->message_requests_count + 1));
	if (connection->message_requests_count - index)
	{
		memmove(connection->message_requests + index + 1, connection->message_requests + index,
			sizeof(tf_ssb_connection_message_request_t) * (connection->message_requests_count - index));
	}
	connection->message_requests[index] = (tf_ssb_connection_message_request_t) {
		.request_number = request_number,
		.keys = keys,
	};
	snprintf(connection->message_requests[index].author, sizeof(connection->message_requests[index].author), "%s", author);
	connection->message_requests_count++;
}

void tf_ssb_connection_remove_new_message_request(tf_ssb_connection_t* connection, const char* author)
{
	int index =
		tf_util_insert_index(author, connection->message_requests, connection->message_requests_count, sizeof(tf_ssb_connection_message_request_t), _message_request_compare);
	if (index < connection->message_requests_count && strcmp(author, connection->message_requests[index].author) == 0)
	{
		memmove(connection->message_requests + index, connection->message_requests + index + 1,
			sizeof(tf_ssb_connection_message_request_t) * (connection->message_requests_count - index - 1));
		connection->message_requests_count--;
	}
}

void tf_ssb_connection_remove_request(tf_ssb_connection_t* connection, int32_t request_number)
{
	tf_ssb_request_t* request =
		connection->requests_count ? bsearch(&request_number, connection->requests, connection->requests_count, sizeof(tf_ssb_request_t), _request_compare) : NULL;
	if (request)
	{
		if (request->cleanup)
		{
			request->cleanup(connection->ssb, request->user_data);
		}
		int index = request - connection->requests;
		memmove(request, request + 1, sizeof(tf_ssb_request_t) * (connection->requests_count - index - 1));
		connection->requests_count--;
		connection->requests = tf_resize_vec(connection->requests, sizeof(tf_ssb_request_t) * connection->requests_count);
		connection->ssb->request_count--;
		_tf_ssb_notify_connections_changed(connection->ssb, k_tf_ssb_change_update, connection);
	}
}

void tf_ssb_connection_rpc_send(tf_ssb_connection_t* connection, uint8_t flags, int32_t request_number, const char* new_request_name, const uint8_t* message, size_t size,
	tf_ssb_rpc_callback_t* callback, tf_ssb_callback_cleanup_t* cleanup, void* user_data)
{
	if (!connection)
	{
		if (cleanup)
		{
			cleanup(NULL, user_data);
		}
		return;
	}
	if (flags & k_ssb_rpc_flag_new_request)
	{
		assert(request_number > 0);
		assert(!_tf_ssb_connection_get_request_callback(connection, request_number, NULL, NULL));
		assert(new_request_name);
	}
	else if (!_tf_ssb_connection_get_request_callback(connection, request_number, NULL, NULL))
	{
		if (flags & k_ssb_rpc_flag_binary)
		{
			tf_printf("Dropping message with no active request (%d): (%zd bytes).\n", request_number, size);
		}
		else
		{
			tf_printf("Dropping message with no active request (%d): %.*s\n", request_number, (int)size, message);
		}
		return;
	}

	uint8_t* combined = tf_malloc(9 + size);
	*combined = flags & k_ssb_rpc_mask_send;
	uint32_t u32size = htonl((uint32_t)size);
	memcpy(combined + 1, &u32size, sizeof(u32size));
	uint32_t rn = htonl((uint32_t)request_number);
	memcpy(combined + 1 + sizeof(uint32_t), &rn, sizeof(rn));
	memcpy(combined + 1 + 2 * sizeof(uint32_t), message, size);
	if (connection->ssb->verbose)
	{
		tf_printf(MAGENTA "%s RPC SEND" RESET " end/error=%s stream=%s type=%s RN=%d: [%zd B] %.*s\n", connection->name, (flags & k_ssb_rpc_flag_end_error) ? "true" : "false",
			(flags & k_ssb_rpc_flag_stream) ? "true" : "false", k_ssb_type_names[flags & k_ssb_rpc_mask_type], request_number, size,
			(flags & k_ssb_rpc_mask_type) == k_ssb_rpc_flag_binary ? 0 : (int)size, message);
	}
	_tf_ssb_connection_add_debug_message(connection, true, flags & k_ssb_rpc_mask_send, request_number, message, size);
	_tf_ssb_connection_box_stream_send(connection, combined, 1 + 2 * sizeof(uint32_t) + size);
	tf_free(combined);
	connection->ssb->rpc_out++;
	if ((flags & k_ssb_rpc_flag_end_error) || (request_number < 0 && !(flags & k_ssb_rpc_flag_stream)))
	{
		tf_ssb_connection_remove_request(connection, request_number);
	}
	else if (flags & k_ssb_rpc_flag_new_request)
	{
		tf_ssb_connection_add_request(connection, request_number, new_request_name, callback, cleanup, user_data, NULL);
	}
}

void tf_ssb_connection_rpc_send_json(tf_ssb_connection_t* connection, uint8_t flags, int32_t request_number, const char* new_request_name, JSValue message,
	tf_ssb_rpc_callback_t* callback, tf_ssb_callback_cleanup_t* cleanup, void* user_data)
{
	JSContext* context = connection->ssb->context;
	JSValue json = JS_JSONStringify(context, message, JS_NULL, JS_NULL);
	size_t size = 0;
	const char* json_string = JS_ToCStringLen(context, &size, json);
	tf_ssb_connection_rpc_send(
		connection, k_ssb_rpc_flag_json | (flags & ~k_ssb_rpc_mask_type), request_number, new_request_name, (const uint8_t*)json_string, size, callback, cleanup, user_data);
	JS_FreeCString(context, json_string);
	JS_FreeValue(context, json);
}

void tf_ssb_connection_rpc_send_error(tf_ssb_connection_t* connection, uint8_t flags, int32_t request_number, const char* error)
{
	JSContext* context = connection->ssb->context;
	JSValue message = JS_NewObject(context);
	const char* stack = tf_util_backtrace_string();
	JS_SetPropertyStr(context, message, "name", JS_NewString(context, "Error"));
	JS_SetPropertyStr(context, message, "stack", JS_NewString(context, stack ? stack : "stack unavailable"));
	JS_SetPropertyStr(context, message, "message", JS_NewString(context, error));
	tf_ssb_connection_rpc_send_json(
		connection, ((flags & k_ssb_rpc_flag_stream) ? (k_ssb_rpc_flag_stream) : 0) | k_ssb_rpc_flag_end_error, request_number, NULL, message, NULL, NULL, NULL);
	JS_FreeValue(context, message);
	tf_free((void*)stack);
}

void tf_ssb_connection_rpc_send_error_method_not_allowed(tf_ssb_connection_t* connection, uint8_t flags, int32_t request_number, const char* name)
{
	char buffer[1024];
	snprintf(buffer, sizeof(buffer), "method '%s' is not in list of allowed methods", name);
	tf_ssb_connection_rpc_send_error(connection, flags, request_number, buffer);
}

static int _utf8_len(uint8_t ch)
{
	static const uint8_t k_length[] = { 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 2, 2, 3, 4 };
	return k_length[(ch & 0xf0) >> 4];
}

static uint32_t _utf8_decode(uint32_t c)
{
	if (c > 0x7f)
	{
		uint32_t mask = (c <= 0x00efbfbf) ? 0x000f0000 : 0x003f0000;
		c = ((c & 0x07000000) >> 6) | ((c & mask) >> 4) | ((c & 0x00003f00) >> 2) | (c & 0x0000003f);
	}
	return c;
}

static const uint8_t* _utf8_to_cp(const uint8_t* ch, uint32_t* out_cp)
{
	int len = _utf8_len(*ch);
	int actual_len = 0;
	uint32_t encoding = 0;
	for (int i = 0; i < len && ch[i]; i++, actual_len++)
	{
		encoding = (encoding << 8) | ch[i];
	}
	*out_cp = _utf8_decode(encoding);
	return ch + actual_len;
}

static uint32_t _cp_to_utf16(uint32_t cp, uint16_t* out_h, uint16_t* out_l)
{
	if (cp < 0x10000)
	{
		*out_h = 0;
		*out_l = cp & 0xffff;
		return cp;
	}
	else
	{
		uint32_t t = cp - 0x10000;
		uint32_t h = ((t << 12) >> 22) + 0xd800;
		uint32_t l = ((t << 22) >> 22) + 0xdc00;
		*out_h = h & 0xffff;
		*out_l = l & 0xffff;
		return (h << 16) | (l & 0xffff);
	}
}

void tf_ssb_calculate_message_id(JSContext* context, JSValue message, char* out_id, size_t out_id_size)
{
	JSValue idval = JS_JSONStringify(context, message, JS_NULL, JS_NewInt32(context, 2));
	size_t len = 0;
	const char* messagestr = JS_ToCStringLen(context, &len, idval);
	if (!messagestr)
	{
		memset(out_id, 0, out_id_size);
		JS_FreeValue(context, idval);
		return;
	}

	char* latin1 = tf_strdup(messagestr);
	uint8_t* write_pos = (uint8_t*)latin1;
	const uint8_t* p = (const uint8_t*)messagestr;
	while (p && *p)
	{
		uint32_t cp = 0;
		p = _utf8_to_cp(p, &cp);
		uint16_t h = 0;
		uint16_t l = 0;
		_cp_to_utf16(cp, &h, &l);
		if (h)
		{
			*write_pos++ = h & 0xff;
		}
		if (l)
		{
			*write_pos++ = l & 0xff;
		}
	}
	size_t latin1_len = write_pos - (uint8_t*)latin1;
	*write_pos++ = '\0';

	uint8_t id[crypto_hash_sha256_BYTES];
	crypto_hash_sha256(id, (uint8_t*)latin1, latin1_len);

	char id_base64[k_id_base64_len];
	tf_base64_encode(id, sizeof(id), id_base64, sizeof(id_base64));

	snprintf(out_id, out_id_size, "%%%s.sha256", id_base64);

	tf_free(latin1);
	JS_FreeCString(context, messagestr);
	JS_FreeValue(context, idval);
}

static bool _tf_ssb_verify_and_strip_signature_internal(JSContext* context, JSValue val, char* out_id, size_t out_id_size, char* out_signature, size_t out_signature_size)
{
	JSValue signature = JS_GetPropertyStr(context, val, "signature");
	if (JS_IsUndefined(signature))
	{
		memset(out_signature, 0, out_signature_size);
		return false;
	}

	const char* str = JS_ToCString(context, signature);
	if (!str)
	{
		JS_FreeValue(context, signature);
		memset(out_signature, 0, out_signature_size);
		return false;
	}

	bool verified = false;
	tf_ssb_calculate_message_id(context, val, out_id, out_id_size);
	JSAtom sigatom = JS_NewAtom(context, "signature");
	JS_DeleteProperty(context, val, sigatom, 0);
	JS_FreeAtom(context, sigatom);

	if (out_signature)
	{
		memset(out_signature, 0, out_signature_size);
		strncpy(out_signature, str, out_signature_size - 1);
	}

	JSValue sigval = JS_JSONStringify(context, val, JS_NULL, JS_NewInt32(context, 2));
	const char* sigstr = JS_ToCString(context, sigval);
	const char* sigkind = strstr(str, ".sig.ed25519");

	JSValue authorval = JS_GetPropertyStr(context, val, "author");
	const char* author = JS_ToCString(context, authorval);
	const char* author_id = author && *author == '@' ? author + 1 : author;
	const char* type = strstr(author_id, ".ed25519");

	uint8_t publickey[crypto_box_PUBLICKEYBYTES];
	int r = tf_base64_decode(author_id, type - author_id, publickey, sizeof(publickey));
	if (r != -1)
	{
		uint8_t binsig[crypto_sign_BYTES];
		r = tf_base64_decode(str, sigkind - str, binsig, sizeof(binsig));
		if (r != -1)
		{
			r = crypto_sign_verify_detached(binsig, (const uint8_t*)sigstr, strlen(sigstr), publickey);
			verified = r == 0;
			if (!verified)
			{
				// tf_printf("crypto_sign_verify_detached fail (r=%d)\n", r);
				if (false)
				{
					tf_printf("val=[%.*s]\n", (int)strlen(sigstr), sigstr);
					tf_printf("sig=%.*s\n", (int)(sigkind - str), str);
					tf_printf("public key=%.*s\n", (int)(type - author_id), author_id);
				}
			}
		}
		else
		{
			tf_printf("base64 decode sig fail [%.*s]\n", (int)(sigkind - str), str);
		}
	}
	else
	{
		tf_printf("base64 decode author[%.*s] fail (%d)\n", (int)(type - author_id), author_id, r);
	}

	JS_FreeCString(context, author);
	JS_FreeCString(context, sigstr);
	JS_FreeCString(context, str);
	JS_FreeValue(context, sigval);
	JS_FreeValue(context, authorval);
	if (verified)
	{
		JS_FreeValue(context, signature);
	}
	else
	{
		JS_SetPropertyStr(context, val, "signature", signature);
	}
	return verified;
}

bool tf_ssb_verify_and_strip_signature(JSContext* context, JSValue val, char* out_id, size_t out_id_size, char* out_signature, size_t out_signature_size, int* out_flags)
{
	JSValue reordered = JS_NewObject(context);
	JS_SetPropertyStr(context, reordered, "previous", JS_GetPropertyStr(context, val, "previous"));
	JS_SetPropertyStr(context, reordered, "author", JS_GetPropertyStr(context, val, "author"));
	JS_SetPropertyStr(context, reordered, "sequence", JS_GetPropertyStr(context, val, "sequence"));
	JS_SetPropertyStr(context, reordered, "timestamp", JS_GetPropertyStr(context, val, "timestamp"));
	JS_SetPropertyStr(context, reordered, "hash", JS_GetPropertyStr(context, val, "hash"));
	JS_SetPropertyStr(context, reordered, "content", JS_GetPropertyStr(context, val, "content"));
	JS_SetPropertyStr(context, reordered, "signature", JS_GetPropertyStr(context, val, "signature"));
	bool result = _tf_ssb_verify_and_strip_signature_internal(context, reordered, out_id, out_id_size, out_signature, out_signature_size);
	JS_FreeValue(context, reordered);

	if (result)
	{
		if (out_flags)
		{
			*out_flags = 0;
		}
		return true;
	}

	reordered = JS_NewObject(context);
	JS_SetPropertyStr(context, reordered, "previous", JS_GetPropertyStr(context, val, "previous"));
	JS_SetPropertyStr(context, reordered, "sequence", JS_GetPropertyStr(context, val, "sequence"));
	JS_SetPropertyStr(context, reordered, "author", JS_GetPropertyStr(context, val, "author"));
	JS_SetPropertyStr(context, reordered, "timestamp", JS_GetPropertyStr(context, val, "timestamp"));
	JS_SetPropertyStr(context, reordered, "hash", JS_GetPropertyStr(context, val, "hash"));
	JS_SetPropertyStr(context, reordered, "content", JS_GetPropertyStr(context, val, "content"));
	JS_SetPropertyStr(context, reordered, "signature", JS_GetPropertyStr(context, val, "signature"));
	result = _tf_ssb_verify_and_strip_signature_internal(context, reordered, out_id, out_id_size, out_signature, out_signature_size);
	JS_FreeValue(context, reordered);
	if (result)
	{
		if (out_flags)
		{
			*out_flags = k_tf_ssb_message_flag_sequence_before_author;
		}
		return true;
	}

	return false;
}

void tf_ssb_close_all(tf_ssb_t* ssb)
{
	for (tf_ssb_connection_t* connection = ssb->connections; connection; connection = connection->next)
	{
		_tf_ssb_connection_close(connection, "tf_ssb_close_all");
	}
}

void tf_ssb_send_close(tf_ssb_t* ssb)
{
	for (tf_ssb_connection_t* connection = ssb->connections; connection; connection = connection->next)
	{
		_tf_ssb_connection_send_close(connection);
	}
}

bool tf_ssb_id_bin_to_str(char* str, size_t str_size, const uint8_t* bin)
{
	char buffer[k_id_base64_len - 9];
	tf_base64_encode(bin, crypto_sign_PUBLICKEYBYTES, buffer, sizeof(buffer));
	return snprintf(str, str_size, "@%s.ed25519", buffer) < (int)str_size;
}

bool tf_ssb_id_str_to_bin(uint8_t* bin, const char* str)
{
	const char* author_id = str && *str == '@' ? str + 1 : str;
	const char* type = str ? strstr(str, ".ed25519") : NULL;
	return author_id && type ? tf_base64_decode(author_id, type - author_id, bin, crypto_box_PUBLICKEYBYTES) != 0 : false;
}

static uint64_t _tf_ssb_callback_pre(tf_ssb_t* ssb)
{
	return uv_hrtime();
}

static void _tf_ssb_callback_post(tf_ssb_t* ssb, void* callback, uint64_t pre)
{
	if (ssb->hitch_callback)
	{
		uint64_t post = uv_hrtime();
		const char* name = tf_util_function_to_string(callback);
		ssb->hitch_callback(name, post - pre, ssb->hitch_user_data);
		tf_free((void*)name);
	}
}

static void _tf_ssb_notify_connections_changed(tf_ssb_t* ssb, tf_ssb_change_t change, tf_ssb_connection_t* connection)
{
	tf_ssb_connections_changed_callback_node_t* next = NULL;
	for (tf_ssb_connections_changed_callback_node_t* node = ssb->connections_changed; node; node = next)
	{
		next = node->next;
		tf_trace_begin(ssb->trace, "connections_changed");
		PRE_CALLBACK(ssb, node->callback);
		node->callback(ssb, change, connection, node->user_data);
		POST_CALLBACK(ssb, node->callback);
		tf_trace_end(ssb->trace);
	}
}

static void _tf_ssb_connection_verify_identity(tf_ssb_connection_t* connection, const uint8_t* message, size_t len)
{
	uint8_t nonce[crypto_secretbox_NONCEBYTES] = { 0 };

	uint8_t shared_secret_ab[crypto_scalarmult_curve25519_SCALARBYTES];
	if (crypto_scalarmult_curve25519(shared_secret_ab, connection->epriv, connection->serverepub) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to compute shared_secret_ab");
		return;
	}

	uint8_t servercurvepub[crypto_scalarmult_curve25519_SCALARBYTES];
	if (crypto_sign_ed25519_pk_to_curve25519(servercurvepub, connection->serverpub) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to convert key to curve25519");
		return;
	}

	uint8_t shared_secret_aB[crypto_scalarmult_curve25519_SCALARBYTES];
	if (crypto_scalarmult_curve25519(shared_secret_aB, connection->epriv, servercurvepub) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to compute shared_secret_aB");
		return;
	}

	uint8_t clientcurvepriv[crypto_scalarmult_curve25519_SCALARBYTES];
	if (crypto_sign_ed25519_sk_to_curve25519(clientcurvepriv, connection->ssb->priv) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to convert key to curve25519");
		return;
	}

	uint8_t shared_secret_Ab[crypto_scalarmult_curve25519_SCALARBYTES];
	if (crypto_scalarmult_curve25519(shared_secret_Ab, clientcurvepriv, connection->serverepub) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to compute shared_secret_Ab");
		return;
	}

	uint8_t tohash[sizeof(connection->ssb->network_key) + sizeof(shared_secret_ab) + sizeof(shared_secret_aB) + sizeof(shared_secret_Ab)];
	memcpy(tohash, connection->ssb->network_key, sizeof(connection->ssb->network_key));
	memcpy(tohash + sizeof(connection->ssb->network_key), shared_secret_ab, sizeof(shared_secret_ab));
	memcpy(tohash + sizeof(connection->ssb->network_key) + sizeof(shared_secret_ab), shared_secret_aB, sizeof(shared_secret_aB));
	memcpy(tohash + sizeof(connection->ssb->network_key) + sizeof(shared_secret_ab) + sizeof(shared_secret_aB), shared_secret_Ab, sizeof(shared_secret_Ab));
	uint8_t hash2[crypto_hash_sha256_BYTES];
	crypto_hash_sha256(hash2, tohash, sizeof(tohash));

	uint8_t hash3a[crypto_hash_sha256_BYTES + crypto_sign_PUBLICKEYBYTES];
	crypto_hash_sha256(hash3a, hash2, sizeof(hash2));
	memcpy(hash3a + crypto_hash_sha256_BYTES, connection->ssb->pub, sizeof(connection->ssb->pub));
	crypto_hash_sha256(connection->s_to_c_box_key, hash3a, sizeof(hash3a));

	uint8_t hash3b[crypto_hash_sha256_BYTES + crypto_sign_PUBLICKEYBYTES];
	crypto_hash_sha256(hash3b, hash2, sizeof(hash2));
	memcpy(hash3b + crypto_hash_sha256_BYTES, connection->serverpub, sizeof(connection->serverpub));
	crypto_hash_sha256(connection->c_to_s_box_key, hash3b, sizeof(hash3b));

	uint8_t m[80];
	if (crypto_secretbox_open_easy(m, message, len, nonce, hash2) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to open initial secret box as client");
		return;
	}

	uint8_t hash3[crypto_hash_sha256_BYTES];
	crypto_hash_sha256(hash3, shared_secret_ab, sizeof(shared_secret_ab));

	uint8_t msg[sizeof(connection->ssb->network_key) + sizeof(connection->detached_signature_A) + sizeof(connection->ssb->pub) + sizeof(hash3)];
	memcpy(msg, connection->ssb->network_key, sizeof(connection->ssb->network_key));
	memcpy(msg + sizeof(connection->ssb->network_key), connection->detached_signature_A, sizeof(connection->detached_signature_A));
	memcpy(msg + sizeof(connection->ssb->network_key) + sizeof(connection->detached_signature_A), connection->ssb->pub, sizeof(connection->ssb->pub));
	memcpy(msg + sizeof(connection->ssb->network_key) + sizeof(connection->detached_signature_A) + sizeof(connection->ssb->pub), hash3, sizeof(hash3));
	if (crypto_sign_verify_detached(m, msg, sizeof(msg), connection->serverpub) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to verify server identity");
		return;
	}

	uint8_t nonce2[crypto_auth_hmacsha512256_BYTES];
	if (crypto_auth_hmacsha512256(nonce2, connection->epub, sizeof(connection->epub), connection->ssb->network_key) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to compute client recv nonce");
		return;
	}
	memcpy(connection->nonce, nonce2, sizeof(connection->nonce));

	uint8_t nonce3[crypto_auth_hmacsha512256_BYTES];
	if (crypto_auth_hmacsha512256(nonce3, connection->serverepub, sizeof(connection->serverepub), connection->ssb->network_key) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to compute client send nonce");
		return;
	}
	memcpy(connection->send_nonce, nonce3, sizeof(connection->send_nonce));

	char fullid[k_id_base64_len];
	tf_ssb_id_bin_to_str(fullid, sizeof(fullid), connection->serverpub);

	JSContext* context = connection->ssb->context;
	JS_SetPropertyStr(context, connection->object, "id", JS_NewString(context, fullid));
	JS_SetPropertyStr(context, connection->object, "is_client", JS_TRUE);

	connection->state = k_tf_ssb_state_verified;
	_tf_ssb_notify_connections_changed(connection->ssb, k_tf_ssb_change_connect, connection);
}

bool tf_ssb_connection_is_client(tf_ssb_connection_t* connection)
{
	return connection->state == k_tf_ssb_state_verified;
}

bool tf_ssb_connection_is_connected(tf_ssb_connection_t* connection)
{
	return connection->state == k_tf_ssb_state_verified || connection->state == k_tf_ssb_state_server_verified;
}

const char* tf_ssb_connection_get_host(tf_ssb_connection_t* connection)
{
	return connection->host;
}

int tf_ssb_connection_get_port(tf_ssb_connection_t* connection)
{
	return connection->port;
}

bool tf_ssb_connection_get_id(tf_ssb_connection_t* connection, char* out_id, size_t out_id_size)
{
	return connection && memcmp(connection->serverpub, (uint8_t[k_id_bin_len]) { 0 }, k_id_bin_len) != 0 && tf_ssb_id_bin_to_str(out_id, out_id_size, connection->serverpub);
}

tf_ssb_connection_t* tf_ssb_connection_get_tunnel(tf_ssb_connection_t* connection)
{
	return connection ? connection->tunnel_connection : NULL;
}

static bool _tf_ssb_is_already_connected(tf_ssb_t* ssb, uint8_t* id, tf_ssb_connection_t* ignore_connection)
{
	for (tf_ssb_connection_t* connection = ssb->connections; connection; connection = connection->next)
	{
		if (!ignore_connection || connection != ignore_connection)
		{
			if (memcmp(connection->serverpub, id, k_id_bin_len) == 0)
			{
				return true;
			}
			else if (memcmp(ssb->pub, id, k_id_bin_len) == 0)
			{
				return true;
			}
		}
	}
	return false;
}

static void _tf_ssb_connection_verify_client_identity(tf_ssb_connection_t* connection, const uint8_t* message, size_t len)
{
	uint8_t nonce[crypto_secretbox_NONCEBYTES] = { 0 };

	/*
	** shared_secret_ab = nacl_scalarmult(
	**   server_ephemeral_sk,
	**   client_ephemeral_pk
	** )
	*/
	uint8_t shared_secret_ab[crypto_scalarmult_curve25519_SCALARBYTES];
	if (crypto_scalarmult_curve25519(shared_secret_ab, connection->epriv, connection->serverepub) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to compute shared_secret_ab");
		return;
	}

	/*
	** shared_secret_aB = nacl_scalarmult(
	**   sk_to_curve25519(server_longterm_sk),
	**   client_ephemeral_pk
	** )
	*/
	uint8_t curvepriv[crypto_scalarmult_curve25519_SCALARBYTES];
	if (crypto_sign_ed25519_sk_to_curve25519(curvepriv, connection->ssb->priv) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to convert key to curve25519");
		return;
	}

	static_assert(sizeof(connection->ssb->priv) == crypto_sign_ed25519_SECRETKEYBYTES, "size");
	uint8_t shared_secret_aB[crypto_scalarmult_curve25519_SCALARBYTES] = { 0 };

	if (crypto_scalarmult(shared_secret_aB, curvepriv, connection->serverepub) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to compute shared_secret_aB");
		return;
	}

	static_assert(sizeof(connection->ssb->network_key) == crypto_auth_KEYBYTES, "network key size");
	uint8_t tohash[sizeof(connection->ssb->network_key) + sizeof(shared_secret_ab) + sizeof(shared_secret_aB)];
	memcpy(tohash, connection->ssb->network_key, sizeof(connection->ssb->network_key));
	memcpy(tohash + sizeof(connection->ssb->network_key), shared_secret_ab, sizeof(shared_secret_ab));
	memcpy(tohash + sizeof(connection->ssb->network_key) + sizeof(shared_secret_ab), shared_secret_aB, sizeof(shared_secret_aB));
	uint8_t hash2[crypto_hash_sha256_BYTES];
	crypto_hash_sha256(hash2, tohash, sizeof(tohash));

	/*
	** msg3_plaintext = assert_nacl_secretbox_open(
	**   ciphertext: msg3,
	**   nonce: 24_bytes_of_zeros,
	**   key: sha256(
	**     concat(
	**       network_identifier,
	**       shared_secret_ab,
	**       shared_secret_aB
	**     )
	**   )
	** )
	*/

	uint8_t m[96];
	if (crypto_secretbox_open_easy(m, message, len, nonce, hash2) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to open initial secret box as server");
		return;
	}
	uint8_t* detached_signature_A = m;

	if (_tf_ssb_is_already_connected(connection->ssb, m + 64, connection))
	{
		char id_base64[k_id_base64_len] = { 0 };
		tf_ssb_id_bin_to_str(id_base64, sizeof(id_base64), m + 64);
		char reason[256];
		snprintf(reason, sizeof(reason), "already connected: %s\n", id_base64);
		_tf_ssb_connection_close(connection, reason);
		return;
	}

	memcpy(connection->serverpub, m + 64, sizeof(connection->serverpub));

	uint8_t hash3[crypto_hash_sha256_BYTES];
	crypto_hash_sha256(hash3, shared_secret_ab, sizeof(shared_secret_ab));

	uint8_t msg[sizeof(connection->ssb->network_key) + sizeof(connection->ssb->pub) + sizeof(hash3)];
	memcpy(msg, connection->ssb->network_key, sizeof(connection->ssb->network_key));
	memcpy(msg + sizeof(connection->ssb->network_key), connection->ssb->pub, sizeof(connection->ssb->pub));
	memcpy(msg + sizeof(connection->ssb->network_key) + sizeof(connection->ssb->pub), hash3, sizeof(hash3));
	if (crypto_sign_verify_detached(detached_signature_A, msg, sizeof(msg), connection->serverpub) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to verify client identity");
		return;
	}

	uint8_t nonce2[crypto_auth_hmacsha512256_BYTES];
	if (crypto_auth_hmacsha512256(nonce2, connection->epub, sizeof(connection->epub), connection->ssb->network_key) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to compute initial recv nonce as server");
		return;
	}
	memcpy(connection->nonce, nonce2, sizeof(connection->nonce));

	uint8_t nonce3[crypto_auth_hmacsha512256_BYTES];
	if (crypto_auth_hmacsha512256(nonce3, connection->serverepub, sizeof(connection->serverepub), connection->ssb->network_key) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to compute initial send nonce as server");
		return;
	}
	memcpy(connection->send_nonce, nonce3, sizeof(connection->send_nonce));

	int detached_signature_A_size = 64;
	uint8_t sign_b[sizeof(connection->ssb->network_key) + detached_signature_A_size + sizeof(connection->serverpub) + sizeof(hash3)];
	memcpy(sign_b, connection->ssb->network_key, sizeof(connection->ssb->network_key));
	memcpy(sign_b + sizeof(connection->ssb->network_key), detached_signature_A, detached_signature_A_size);
	memcpy(sign_b + sizeof(connection->ssb->network_key) + detached_signature_A_size, connection->serverpub, sizeof(connection->serverpub));
	memcpy(sign_b + sizeof(connection->ssb->network_key) + detached_signature_A_size + sizeof(connection->serverpub), hash3, sizeof(hash3));

	uint8_t detached_signature_B[crypto_sign_BYTES];
	unsigned long long siglen;
	if (crypto_sign_detached(detached_signature_B, &siglen, sign_b, sizeof(sign_b), connection->ssb->priv) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to compute detached_signature_B as server");
		return;
	}

	uint8_t clientcurvepub[crypto_scalarmult_curve25519_SCALARBYTES];
	if (crypto_sign_ed25519_pk_to_curve25519(clientcurvepub, connection->serverpub) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to convert key to curve25519");
		return;
	}

	uint8_t shared_secret_Ab[crypto_scalarmult_curve25519_SCALARBYTES];
	if (crypto_scalarmult_curve25519(shared_secret_Ab, connection->epriv, clientcurvepub) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to compute shared_secret_Ab as server");
		return;
	}

	uint8_t key_buf[sizeof(connection->ssb->network_key) + sizeof(shared_secret_ab) + sizeof(shared_secret_aB) + sizeof(shared_secret_Ab)];
	memcpy(key_buf, connection->ssb->network_key, sizeof(connection->ssb->network_key));
	memcpy(key_buf + sizeof(connection->ssb->network_key), shared_secret_ab, sizeof(shared_secret_ab));
	memcpy(key_buf + sizeof(connection->ssb->network_key) + sizeof(shared_secret_ab), shared_secret_aB, sizeof(shared_secret_aB));
	memcpy(key_buf + sizeof(connection->ssb->network_key) + sizeof(shared_secret_ab) + sizeof(shared_secret_aB), shared_secret_Ab, sizeof(shared_secret_Ab));

	uint8_t key_hash[crypto_hash_sha256_BYTES];
	crypto_hash_sha256(key_hash, key_buf, sizeof(key_buf));

	uint8_t hash3a[crypto_hash_sha256_BYTES + crypto_sign_PUBLICKEYBYTES];
	crypto_hash_sha256(hash3a, key_hash, sizeof(key_hash));
	memcpy(hash3a + crypto_hash_sha256_BYTES, connection->ssb->pub, sizeof(connection->ssb->pub));
	crypto_hash_sha256(connection->s_to_c_box_key, hash3a, sizeof(hash3a));

	uint8_t hash3b[crypto_hash_sha256_BYTES + crypto_sign_PUBLICKEYBYTES];
	crypto_hash_sha256(hash3b, key_hash, sizeof(key_hash));
	memcpy(hash3b + crypto_hash_sha256_BYTES, connection->serverpub, sizeof(connection->serverpub));
	crypto_hash_sha256(connection->c_to_s_box_key, hash3b, sizeof(hash3b));

	uint8_t c[crypto_secretbox_MACBYTES + sizeof(detached_signature_B)];
	if (crypto_secretbox_easy(c, detached_signature_B, sizeof(detached_signature_B), nonce, key_hash) != 0)
	{
		_tf_ssb_connection_close(connection, "unable to create initial secret box as server");
		return;
	}

	static_assert(sizeof(c) == 80, "server send size");
	_tf_ssb_write(connection, c, sizeof(c));

	char fullid[k_id_base64_len];
	tf_ssb_id_bin_to_str(fullid, sizeof(fullid), connection->serverpub);

	JSContext* context = connection->ssb->context;
	JS_SetPropertyStr(context, connection->object, "id", JS_NewString(context, fullid));
	JS_SetPropertyStr(context, connection->object, "is_client", JS_FALSE);

	connection->state = k_tf_ssb_state_server_verified;
	_tf_ssb_notify_connections_changed(connection->ssb, k_tf_ssb_change_connect, connection);
}

static bool _tf_ssb_connection_recv_pop(tf_ssb_connection_t* connection, uint8_t* buffer, size_t size)
{
	if (size >= sizeof(connection->recv_buffer))
	{
		char message[256];
		snprintf(message, sizeof(message), "Trying to pop a message (%zd) larger than the connection's receive buffer (%zd).", size, sizeof(connection->recv_buffer));
		_tf_ssb_connection_close(connection, message);
	}
	if (connection->recv_size < size)
	{
		return false;
	}

	memcpy(buffer, connection->recv_buffer, size);
	if (connection->recv_size - size)
	{
		memmove(connection->recv_buffer, connection->recv_buffer + size, connection->recv_size - size);
	}
	connection->recv_size -= size;
	return true;
}

static bool _tf_ssb_name_equals(JSContext* context, JSValue object, const char** match)
{
	bool result = true;
	JSValue name = JS_GetPropertyStr(context, object, "name");

	if (JS_IsArray(context, name))
	{
		int length = tf_util_get_length(context, name);
		for (int i = 0; i < length; i++)
		{
			if (!match[i])
			{
				result = false;
				break;
			}

			JSValue element = JS_GetPropertyUint32(context, name, i);
			const char* str = JS_ToCString(context, element);
			if (!str || strcmp(str, match[i]) != 0)
			{
				result = false;
			}
			JS_FreeCString(context, str);
			JS_FreeValue(context, element);
		}
		if (result && match[length])
		{
			result = false;
		}
	}
	else if (JS_IsString(name))
	{
		/* Manifest is traditionally sent as not an array for some reason. */
		const char* str = JS_ToCString(context, name);
		result = str && match[0] && strcmp(str, match[0]) == 0 && !match[1];
		JS_FreeCString(context, str);
	}
	else
	{
		result = false;
	}

	JS_FreeValue(context, name);
	return result;
}

static void _tf_ssb_name_to_string(JSContext* context, JSValue object, char* buffer, size_t size)
{
	JSValue name = JS_GetPropertyStr(context, object, "name");
	JSValue json_val = JS_JSONStringify(context, name, JS_NULL, JS_NewInt32(context, 2));
	const char* value = JS_ToCString(context, json_val);
	snprintf(buffer, size, "%s", value);
	JS_FreeCString(context, value);
	JS_FreeValue(context, json_val);
	JS_FreeValue(context, name);
}

static void _tf_ssb_connection_rpc_recv(tf_ssb_connection_t* connection, uint8_t flags, int32_t request_number, const uint8_t* message, size_t size)
{
	connection->ssb->rpc_in++;
	_tf_ssb_connection_add_debug_message(connection, false, flags, request_number, message, size);
	bool close_connection = false;
	if (size == 0)
	{
		_tf_ssb_connection_close(connection, "rpc recv zero");
		return;
	}
	else if (flags & k_ssb_rpc_flag_json)
	{
		char id[k_id_base64_len] = "";
		tf_ssb_id_bin_to_str(id, sizeof(id), connection->serverpub);
		if (connection->ssb->verbose)
		{
			tf_printf(CYAN "%s RPC RECV" RESET " end/error=%s stream=%s type=%s RN=%d: [%zd B] %.*s\n", connection->name, (flags & k_ssb_rpc_flag_end_error) ? "true" : "false",
				(flags & k_ssb_rpc_flag_stream) ? "true" : "false", k_ssb_type_names[flags & k_ssb_rpc_mask_type], request_number, size, (int)size, message);
		}
		JSContext* context = connection->ssb->context;
		JSValue val = JS_ParseJSON(context, (const char*)message, size, NULL);

		if (!JS_IsUndefined(val))
		{
			tf_ssb_rpc_callback_t* callback = NULL;
			void* user_data = NULL;
			if (_tf_ssb_connection_get_request_callback(connection, -request_number, &callback, &user_data))
			{
				if (callback)
				{
					char buffer[64];
					snprintf(buffer, sizeof(buffer), "request %d", request_number);
					tf_trace_begin(connection->ssb->trace, buffer);
					PRE_CALLBACK(connection->ssb, callback);
					callback(connection, flags, request_number, val, message, size, user_data);
					POST_CALLBACK(connection->ssb, callback);
					tf_trace_end(connection->ssb->trace);
					if (!(flags & k_ssb_rpc_flag_stream))
					{
						tf_ssb_connection_remove_request(connection, -request_number);
					}
				}
			}
			else if (JS_IsObject(val))
			{
				bool found = false;
				char namebuf[256] = "";
				JSValue name = JS_GetPropertyStr(context, val, "name");
				if (JS_IsArray(context, name))
				{
					int length = tf_util_get_length(context, name);
					int offset = 0;
					for (int i = 0; i < length; i++)
					{
						JSValue part = JS_GetPropertyUint32(context, name, i);
						const char* part_str = JS_ToCString(context, part);
						offset += snprintf(namebuf + offset, sizeof(namebuf) - offset, "%s%s", i == 0 ? "" : ".", part_str);
						JS_FreeCString(context, part_str);
						JS_FreeValue(context, part);
					}
				}
				else if (JS_IsString(name))
				{
					const char* part_str = JS_ToCString(context, name);
					snprintf(namebuf, sizeof(namebuf), "%s", part_str);
					JS_FreeCString(context, part_str);
				}
				JS_FreeValue(context, name);

				for (tf_ssb_rpc_callback_node_t* it = connection->ssb->rpc; it; it = it->next)
				{
					if (_tf_ssb_name_equals(context, val, it->name))
					{
						tf_ssb_connection_add_request(connection, -request_number, namebuf, NULL, NULL, NULL, NULL);
						tf_trace_begin(connection->ssb->trace, it->flattened_name);
						PRE_CALLBACK(connection->ssb, it->callback);
						it->callback(connection, flags, request_number, val, message, size, it->user_data);
						POST_CALLBACK(connection->ssb, it->callback);
						tf_trace_end(connection->ssb->trace);
						found = true;
						break;
					}
				}
				if (!found && !_tf_ssb_name_equals(context, val, (const char*[]) { "Error", NULL }))
				{
					tf_ssb_connection_add_request(connection, -request_number, namebuf, NULL, NULL, NULL, NULL);
					char buffer[256];
					_tf_ssb_name_to_string(context, val, buffer, sizeof(buffer));
					tf_ssb_connection_rpc_send_error_method_not_allowed(connection, flags, -request_number, buffer);
				}
			}
		}
		else
		{
			tf_printf("Failed to parse %.*s\n", (int)size, message);
			close_connection = true;
		}

		JS_FreeValue(context, val);
	}
	else if ((flags & k_ssb_rpc_mask_type) == k_ssb_rpc_flag_binary)
	{
		if (connection->ssb->verbose)
		{
			tf_printf(CYAN "%s RPC RECV" RESET " end/error=%s stream=%s type=%s RN=%d: [%zd B]\n", connection->name, (flags & k_ssb_rpc_flag_end_error) ? "true" : "false",
				(flags & k_ssb_rpc_flag_stream) ? "true" : "false", k_ssb_type_names[flags & k_ssb_rpc_mask_type], request_number, size);
		}
		tf_ssb_rpc_callback_t* callback = NULL;
		void* user_data = NULL;
		if (_tf_ssb_connection_get_request_callback(connection, -request_number, &callback, &user_data))
		{
			if (callback)
			{
				char buffer[64];
				snprintf(buffer, sizeof(buffer), "request %d", request_number);
				tf_trace_begin(connection->ssb->trace, buffer);
				PRE_CALLBACK(connection->ssb, callback);
				callback(connection, flags, request_number, JS_UNDEFINED, message, size, user_data);
				POST_CALLBACK(connection->ssb, callback);
				tf_trace_end(connection->ssb->trace);
			}
		}
	}

	if (close_connection)
	{
		tf_ssb_connection_close(connection);
	}
}

static void _tf_ssb_connection_rpc_recv_push(tf_ssb_connection_t* connection, const uint8_t* data, size_t size)
{
	size_t size_left = size;
	size_t size_processed = 0;
	while (size_left > 0)
	{
		size_t copy_size =
			(connection->rpc_recv_size + size_left > sizeof(connection->rpc_recv_buffer)) ? sizeof(connection->rpc_recv_buffer) - connection->rpc_recv_size : size_left;
		if (copy_size == 0)
		{
			_tf_ssb_connection_close(connection, "recv buffer overflow");
			return;
		}
		memcpy(connection->rpc_recv_buffer + connection->rpc_recv_size, data + size_processed, copy_size);
		connection->rpc_recv_size += copy_size;
		size_processed += copy_size;
		size_left -= copy_size;

		while (connection->rpc_recv_size >= 9)
		{
			uint8_t flags = *connection->rpc_recv_buffer;
			uint32_t body_len;
			int32_t request_number;
			memcpy(&body_len, connection->rpc_recv_buffer + 1, sizeof(body_len));
			body_len = htonl(body_len);
			memcpy(&request_number, connection->rpc_recv_buffer + 1 + sizeof(body_len), sizeof(request_number));
			request_number = htonl(request_number);

			size_t rpc_size = 9 + body_len;
			if (connection->rpc_recv_size >= rpc_size)
			{
				uint8_t* end = &connection->rpc_recv_buffer[9 + body_len];
				uint8_t tmp = *end;
				*end = '\0';
				_tf_ssb_connection_rpc_recv(connection, flags, request_number, connection->rpc_recv_buffer + 9, body_len);
				*end = tmp;
				memmove(connection->rpc_recv_buffer, connection->rpc_recv_buffer + rpc_size, connection->rpc_recv_size - rpc_size);
				connection->rpc_recv_size -= rpc_size;
			}
			else
			{
				/* Wait for more body. */
				break;
			}
		}
	}
}

static bool _tf_ssb_connection_box_stream_recv(tf_ssb_connection_t* connection)
{
	if (!connection->body_len)
	{
		uint8_t header_enc[34];
		if (_tf_ssb_connection_recv_pop(connection, header_enc, sizeof(header_enc)))
		{
			uint8_t header[18];
			if (crypto_secretbox_open_easy(header, header_enc, sizeof(header_enc), connection->nonce, connection->s_to_c_box_key) != 0)
			{
				_tf_ssb_connection_close(connection, "failed to open header secret box");
				return false;
			}
			_tf_ssb_nonce_inc(connection->nonce);
			connection->body_len = htons(*(uint16_t*)header);
			memcpy(connection->body_auth_tag, header + sizeof(uint16_t), sizeof(connection->body_auth_tag));
			if (!connection->body_len)
			{
				_tf_ssb_connection_close(connection, "empty body, graceful close");
			}
		}
		else
		{
			return false;
		}
	}

	if (connection->body_len)
	{
		memcpy(connection->box_stream_buf, connection->body_auth_tag, sizeof(connection->body_auth_tag));
		if (_tf_ssb_connection_recv_pop(connection, connection->box_stream_buf + 16, connection->body_len))
		{
			if (crypto_secretbox_open_easy(connection->secretbox_buf, connection->box_stream_buf, 16 + connection->body_len, connection->nonce, connection->s_to_c_box_key) != 0)
			{
				_tf_ssb_connection_close(connection, "failed to open secret box");
				return false;
			}
			_tf_ssb_nonce_inc(connection->nonce);
			_tf_ssb_connection_rpc_recv_push(connection, connection->secretbox_buf, connection->body_len);
			connection->body_len = 0;
		}
		else
		{
			return false;
		}
	}

	return true;
}

JSValue tf_ssb_sign_message(tf_ssb_t* ssb, const char* author, const uint8_t* private_key, JSValue message, const char* previous_id, int64_t previous_sequence)
{
	char actual_previous_id[crypto_hash_sha256_BYTES * 2];
	int64_t actual_previous_sequence = 0;
	bool have_previous = false;
	if (previous_id)
	{
		have_previous = *previous_id && previous_sequence > 0;
		snprintf(actual_previous_id, sizeof(actual_previous_id), "%s", previous_id);
		actual_previous_sequence = previous_sequence;
	}
	else
	{
		have_previous = tf_ssb_db_get_latest_message_by_author(ssb, author, &actual_previous_sequence, actual_previous_id, sizeof(actual_previous_id));
	}

	JSContext* context = ssb->context;
	JSValue root = JS_NewObject(context);

	JS_SetPropertyStr(context, root, "previous", have_previous ? JS_NewString(context, actual_previous_id) : JS_NULL);
	JS_SetPropertyStr(context, root, "author", JS_NewString(context, author));
	JS_SetPropertyStr(context, root, "sequence", JS_NewInt64(context, actual_previous_sequence + 1));

	int64_t now = (int64_t)time(NULL);
	JS_SetPropertyStr(context, root, "timestamp", JS_NewInt64(context, now * 1000LL));
	JSValue hashstr = JS_NewString(context, "sha256");
	JS_SetPropertyStr(context, root, "hash", hashstr);
	JSValue content = JS_DupValue(context, message);
	JS_SetPropertyStr(context, root, "content", content);

	JSValue jsonval = JS_JSONStringify(context, root, JS_NULL, JS_NewInt32(context, 2));
	size_t len = 0;
	const char* json = JS_ToCStringLen(context, &len, jsonval);
	JS_FreeValue(context, jsonval);

	uint8_t signature[crypto_sign_BYTES];
	unsigned long long siglen;
	bool valid = crypto_sign_detached(signature, &siglen, (const uint8_t*)json, len, private_key) == 0;
	JS_FreeCString(context, json);

	if (!valid)
	{
		tf_printf("crypto_sign_detached failed\n");
		JS_FreeValue(context, root);
		root = JS_UNDEFINED;
	}
	else
	{
		char signature_base64[crypto_sign_BYTES * 2];
		tf_base64_encode(signature, sizeof(signature), signature_base64, sizeof(signature_base64));
		strcat(signature_base64, ".sig.ed25519");
		JSValue sigstr = JS_NewString(context, signature_base64);
		JS_SetPropertyStr(context, root, "signature", sigstr);
	}

	return root;
}

static void _tf_ssb_connection_destroy(tf_ssb_connection_t* connection, const char* reason)
{
	tf_ssb_t* ssb = connection->ssb;
	connection->closing = true;
	if (!connection->destroy_reason)
	{
		connection->destroy_reason = reason;
	}
	_tf_ssb_connection_dispatch_scheduled(connection);
	tf_free(connection->scheduled);
	connection->scheduled = NULL;
	while (connection->requests)
	{
		tf_ssb_connection_remove_request(connection, connection->requests->request_number);
	}
	for (tf_ssb_broadcast_t* node = ssb->broadcasts; node; node = node->next)
	{
		if (node->tunnel_connection == connection)
		{
			node->tunnel_connection = NULL;
			node->mtime = 0;
		}
	}
	for (tf_ssb_connection_t** it = &connection->ssb->connections; *it; it = &(*it)->next)
	{
		for (int i = (*it)->requests_count - 1; i >= 0; i--)
		{
			if ((*it)->requests[i].dependent_connection == connection)
			{
				tf_ssb_connection_remove_request(*it, (*it)->requests[i].request_number);
			}
		}
		if (*it == connection)
		{
			*it = connection->next;
			connection->next = NULL;
			ssb->connections_count--;
			_tf_ssb_notify_connections_changed(ssb, k_tf_ssb_change_remove, connection);
			break;
		}
	}
	bool again = true;
	while (again)
	{
		again = false;
		for (tf_ssb_connection_t* it = connection->ssb->connections; it; it = it->next)
		{
			if (it->tunnel_connection == connection)
			{
				it->tunnel_connection = NULL;
				_tf_ssb_connection_close(it, "tunnel closed");
				again = true;
				break;
			}
			else if (it == connection->tunnel_connection)
			{
				tf_ssb_connection_remove_request(it, connection->tunnel_request_number);
				connection->tunnel_connection = NULL;
				connection->tunnel_request_number = 0;
			}
		}
	}
	if (!JS_IsUndefined(connection->object))
	{
		JSValue object = connection->object;
		connection->object = JS_UNDEFINED;
		JS_SetOpaque(object, NULL);
		JS_FreeValue(ssb->context, object);
	}
	if (connection->async.data && !uv_is_closing((uv_handle_t*)&connection->async))
	{
		uv_close((uv_handle_t*)&connection->async, _tf_ssb_connection_on_close);
	}
	if (connection->tcp.data && !uv_is_closing((uv_handle_t*)&connection->tcp))
	{
		uv_close((uv_handle_t*)&connection->tcp, _tf_ssb_connection_on_close);
	}

	if (JS_IsUndefined(connection->object) && !connection->async.data && !connection->tcp.data && !connection->connect.data && connection->ref_count == 0)
	{
		tf_free(connection->message_requests);
		connection->message_requests = NULL;
		connection->message_requests_count = 0;

		for (int i = 0; i < k_debug_close_message_count; i++)
		{
			tf_free(connection->debug_messages[i]);
			connection->debug_messages[i] = NULL;
		}

		if (--connection->ssb->connection_ref_count == 0 && connection->ssb->shutting_down)
		{
			tf_ssb_destroy(connection->ssb);
		}
		tf_free(connection);
	}
}

static void _tf_ssb_connection_on_close(uv_handle_t* handle)
{
	tf_ssb_connection_t* connection = handle->data;
	handle->data = NULL;
	if (connection)
	{
		_tf_ssb_connection_destroy(connection, "handle closed");
	}
}

static void _tf_ssb_connection_on_tcp_recv_internal(tf_ssb_connection_t* connection, const void* data, ssize_t nread)
{
	if (nread >= 0)
	{
		if (connection->recv_size + nread > sizeof(connection->recv_buffer))
		{
			_tf_ssb_connection_close(connection, "recv buffer overflow");
			return;
		}
		memcpy(connection->recv_buffer + connection->recv_size, data, nread);
		connection->recv_size += nread;

		switch (connection->state)
		{
		case k_tf_ssb_state_invalid:
			_tf_ssb_connection_close(connection, "received a message in invalid state");
			break;
		case k_tf_ssb_state_connected:
			_tf_ssb_connection_close(connection, "received a message in connected state");
			break;
		case k_tf_ssb_state_sent_hello:
			{
				uint8_t hello[64];
				if (_tf_ssb_connection_recv_pop(connection, hello, sizeof(hello)))
				{
					_tf_ssb_connection_send_identity(connection, hello, hello + 32);
				}
			}
			break;
		case k_tf_ssb_state_sent_identity:
			{
				uint8_t identity[80];
				if (_tf_ssb_connection_recv_pop(connection, identity, sizeof(identity)))
				{
					_tf_ssb_connection_verify_identity(connection, identity, sizeof(identity));
				}
			}
			break;
		case k_tf_ssb_state_verified:
			uv_async_send(&connection->async);
			break;
		case k_tf_ssb_state_server_wait_hello:
			{
				uint8_t hello[64];
				if (_tf_ssb_connection_recv_pop(connection, hello, sizeof(hello)))
				{
					uint8_t* hmac = hello;
					memcpy(connection->serverepub, hello + crypto_box_PUBLICKEYBYTES, crypto_box_PUBLICKEYBYTES);
					static_assert(sizeof(connection->serverepub) == crypto_box_PUBLICKEYBYTES, "serverepub size");
					if (crypto_auth_hmacsha512256_verify(hmac, connection->serverepub, 32, connection->ssb->network_key) != 0)
					{
						_tf_ssb_connection_close(connection, "crypto_auth_hmacsha512256_verify failed");
					}
					else
					{
						_tf_ssb_connection_client_send_hello(connection);
						connection->state = k_tf_ssb_state_server_wait_client_identity;
					}
				}
			}
			break;
		case k_tf_ssb_state_server_wait_client_identity:
			{
				uint8_t identity[112];
				if (_tf_ssb_connection_recv_pop(connection, identity, sizeof(identity)))
				{
					_tf_ssb_connection_verify_client_identity(connection, identity, sizeof(identity));
				}
			}
			break;
		case k_tf_ssb_state_server_verified:
			uv_async_send(&connection->async);
			break;
		case k_tf_ssb_state_closing:
			break;
		}
	}
	else if (nread == UV_ENOBUFS)
	{
		/* Our read buffer is full.  Try harder to process messages. */
		uv_async_send(&connection->async);
	}
	else
	{
		_tf_ssb_connection_close(connection, uv_strerror(nread));
	}
}

static void _tf_ssb_connection_on_tcp_recv(uv_stream_t* stream, ssize_t nread, const uv_buf_t* buf)
{
	tf_ssb_connection_t* connection = stream->data;
	_tf_ssb_connection_on_tcp_recv_internal(connection, buf->base, nread);
	tf_free(buf->base);
}

static void _tf_ssb_connection_client_send_hello(tf_ssb_connection_t* connection)
{
	char write[crypto_auth_BYTES + crypto_box_PUBLICKEYBYTES];

	if (crypto_box_keypair(connection->epub, connection->epriv) != 0)
	{
		_tf_ssb_connection_close(connection, "failed to generate ephemeral keypair");
		return;
	}

	uint8_t a[crypto_auth_hmacsha512256_BYTES];
	if (crypto_auth_hmacsha512256(a, connection->epub, sizeof(connection->epub), connection->ssb->network_key) != 0)
	{
		_tf_ssb_connection_close(connection, "failed to create hello message");
		return;
	}

	char* b = write;
	memcpy(b, a, crypto_auth_BYTES);
	memcpy(b + crypto_auth_BYTES, connection->epub, sizeof(connection->epub));

	_tf_ssb_write(connection, b, crypto_auth_BYTES + sizeof(connection->epub));
	connection->state = k_tf_ssb_state_sent_hello;
}

static bool _tf_ssb_connection_read_start(tf_ssb_connection_t* connection)
{
	int result = uv_read_start((uv_stream_t*)&connection->tcp, _tf_ssb_connection_on_tcp_alloc, _tf_ssb_connection_on_tcp_recv);
	if (result && result != UV_EALREADY)
	{
		tf_printf("uv_read_start => %s\n", uv_strerror(result));
		_tf_ssb_connection_close(connection, "uv_read_start failed");
		return false;
	}
	return true;
}

static bool _tf_ssb_connection_read_stop(tf_ssb_connection_t* connection)
{
	int result = uv_read_stop((uv_stream_t*)&connection->tcp);
	if (result && result != UV_EALREADY)
	{
		tf_printf("uv_read_stop => %s\n", uv_strerror(result));
		_tf_ssb_connection_close(connection, "uv_read_stop failed");
		return false;
	}
	return true;
}

static void _tf_ssb_connection_on_connect(uv_connect_t* connect, int status)
{
	tf_ssb_connection_t* connection = connect->data;
	connect->data = NULL;
	if (status == 0)
	{
		connection->state = k_tf_ssb_state_connected;
		if (_tf_ssb_connection_read_start(connection))
		{
			_tf_ssb_connection_client_send_hello(connection);
		}
	}
	else
	{
		_tf_ssb_connection_close(connection, "uv_tcp_connect failed");
	}
}

static void _load_keys_callback(const char* identity, void* user_data)
{
	tf_ssb_t* ssb = user_data;
	if (*ssb->pub)
	{
		return;
	}

	tf_ssb_id_str_to_bin(ssb->pub, identity);
	tf_ssb_db_identity_get_private_key(ssb, ":admin", identity, ssb->priv, sizeof(ssb->priv));
}

static bool _tf_ssb_load_keys(tf_ssb_t* ssb)
{
	tf_ssb_db_identity_visit(ssb, ":admin", _load_keys_callback, ssb);
	return *ssb->pub != '\0' && *ssb->priv != '\0';
}

static void _tf_ssb_trace_timer(uv_timer_t* timer)
{
	tf_ssb_t* ssb = timer->data;

	const char* names[] = {
		"connections",
		"broadcasts",
		"rpc",
		"connections_changed",
		"message_added",
		"blob_want_added",
		"broadcasts_changed",
	};
	int64_t values[] = {
		ssb->connections_count,
		ssb->broadcasts_count,
		ssb->rpc_count,
		ssb->connections_changed_count,
		ssb->message_added_count,
		ssb->blob_want_added_count,
		ssb->broadcasts_changed_count,
	};

	tf_trace_counter(ssb->trace, "ssb", _countof(values), names, values);
}

void tf_ssb_get_stats(tf_ssb_t* ssb, tf_ssb_stats_t* out_stats)
{
	*out_stats = (tf_ssb_stats_t)
	{
		.connections = ssb->connections_count,
		.broadcasts = ssb->broadcasts_count,
		.messages_stored = ssb->messages_stored,
		.blobs_stored = ssb->blobs_stored,
		.rpc_in = ssb->rpc_in,
		.rpc_out = ssb->rpc_out,
		.request_count = ssb->request_count,
		.callbacks =
		{
			.rpc = ssb->rpc_count,
			.connections_changed = ssb->connections_changed_count,
			.message_added = ssb->message_added_count,
			.blob_want_added = ssb->blob_want_added_count,
			.broadcasts_changed = ssb->broadcasts_changed_count,
		},
	};
	ssb->messages_stored = 0;
	ssb->blobs_stored = 0;
	ssb->rpc_in = 0;
	ssb->rpc_out = 0;
}

tf_ssb_t* tf_ssb_create(uv_loop_t* loop, JSContext* context, const char* db_path, const char* network_key)
{
	tf_ssb_t* ssb = tf_malloc(sizeof(tf_ssb_t));
	memset(ssb, 0, sizeof(*ssb));

	const char* actual_key = network_key ? network_key : k_ssb_network_string;
	if (sodium_hex2bin(ssb->network_key, sizeof(ssb->network_key), actual_key, strlen(actual_key), ": ", NULL, NULL))
	{
		tf_printf("Error parsing network key: %s.", actual_key);
	}

	char buffer[8] = { 0 };
	size_t buffer_size = sizeof(buffer);
	ssb->store_debug_messages = uv_os_getenv("TF_DEBUG_CLOSE", buffer, &buffer_size) == 0 && strcmp(buffer, "1") == 0;
	buffer_size = sizeof(buffer);
	ssb->verbose = uv_os_getenv("TF_SSB_VERBOSE", buffer, &buffer_size) == 0 && strcmp(buffer, "1") == 0;

	if (context)
	{
		ssb->context = context;
	}
	else
	{
		ssb->own_context = true;
		JSMallocFunctions funcs = { 0 };
		tf_get_js_malloc_functions(&funcs);
		ssb->runtime = JS_NewRuntime2(&funcs, NULL);
		ssb->context = JS_NewContext(ssb->runtime);
	}

	uv_mutex_init(&ssb->db_readers_lock);
	uv_mutex_init(&ssb->db_writer_lock);

	JS_NewClassID(&_connection_class_id);
	JSClassDef def = {
		.class_name = "connection",
		.finalizer = _tf_ssb_connection_finalizer,
	};
	JS_NewClass(JS_GetRuntime(ssb->context), _connection_class_id, &def);

	ssb->db_path = tf_strdup(db_path);
	sqlite3_open_v2(db_path, &ssb->db_writer, SQLITE_OPEN_READWRITE | SQLITE_OPEN_URI | SQLITE_OPEN_CREATE, NULL);
	tf_ssb_db_init(ssb);

	if (loop)
	{
		ssb->loop = loop;
	}
	else
	{
		uv_loop_init(&ssb->own_loop);
		ssb->loop = &ssb->own_loop;
	}

	ssb->broadcast_timer.data = ssb;
	uv_timer_init(ssb->loop, &ssb->broadcast_timer);

	ssb->trace_timer.data = ssb;
	uv_timer_init(ssb->loop, &ssb->trace_timer);
	uv_timer_start(&ssb->trace_timer, _tf_ssb_trace_timer, 100, 100);
	uv_unref((uv_handle_t*)&ssb->trace_timer);

	if (!_tf_ssb_load_keys(ssb))
	{
		tf_printf("Generating a new keypair.\n");
		tf_ssb_db_identity_create(ssb, ":admin", ssb->pub, ssb->priv);
	}

	ssb->connections_tracker = tf_ssb_connections_create(ssb);

	_tf_ssb_update_settings(ssb);
	tf_ssb_rpc_register(ssb);
	_tf_ssb_start_update_settings(ssb);
	return ssb;
}

void tf_ssb_start_periodic(tf_ssb_t* ssb)
{
	tf_ssb_rpc_start_periodic(ssb);
}

static void _tf_ssb_assert_not_main_thread(tf_ssb_t* ssb)
{
	if (uv_thread_self() == ssb->thread_self)
	{
		const char* bt = tf_util_backtrace_string();
		tf_printf("Acquiring DB from the main thread:\n%s\n", bt);
		tf_free((void*)bt);
		abort();
	}
}

sqlite3* tf_ssb_acquire_db_reader(tf_ssb_t* ssb)
{
	tf_trace_begin(ssb->trace, "db_reader");
	_tf_ssb_assert_not_main_thread(ssb);
	sqlite3* db = NULL;
	uv_mutex_lock(&ssb->db_readers_lock);
	if (ssb->db_readers_count)
	{
		db = ssb->db_readers[--ssb->db_readers_count];
	}
	else
	{
		sqlite3_open_v2(ssb->db_path, &db, SQLITE_OPEN_READONLY | SQLITE_OPEN_URI, NULL);
		tf_ssb_db_init_reader(db);
	}
	tf_trace_sqlite(ssb->trace, db);
	uv_mutex_unlock(&ssb->db_readers_lock);
	sqlite3_set_authorizer(db, NULL, NULL);
	return db;
}

sqlite3* tf_ssb_acquire_db_reader_restricted(tf_ssb_t* ssb)
{
	sqlite3* db = tf_ssb_acquire_db_reader(ssb);
	sqlite3_set_authorizer(db, tf_ssb_sqlite_authorizer, ssb);
	return db;
}

void tf_ssb_release_db_reader(tf_ssb_t* ssb, sqlite3* db)
{
	sqlite3_db_release_memory(db);
	uv_mutex_lock(&ssb->db_readers_lock);
	ssb->db_readers = tf_resize_vec(ssb->db_readers, sizeof(sqlite3*) * (ssb->db_readers_count + 1));
	ssb->db_readers[ssb->db_readers_count++] = db;
	uv_mutex_unlock(&ssb->db_readers_lock);
	tf_trace_end(ssb->trace);
}

sqlite3* tf_ssb_acquire_db_writer(tf_ssb_t* ssb)
{
	tf_trace_begin(ssb->trace, "db_writer");
	_tf_ssb_assert_not_main_thread(ssb);
	uv_mutex_lock(&ssb->db_writer_lock);
	sqlite3* writer = ssb->db_writer;
	assert(writer);
	ssb->db_writer = NULL;
	return writer;
}

void tf_ssb_release_db_writer(tf_ssb_t* ssb, sqlite3* db)
{
	assert(ssb->db_writer == NULL);
	sqlite3_db_release_memory(db);
	ssb->db_writer = db;
	uv_mutex_unlock(&ssb->db_writer_lock);
	tf_trace_end(ssb->trace);
}

uv_loop_t* tf_ssb_get_loop(tf_ssb_t* ssb)
{
	return ssb->loop;
}

void tf_ssb_generate_keys(tf_ssb_t* ssb)
{
	crypto_sign_ed25519_keypair(ssb->pub, ssb->priv);
}

void tf_ssb_generate_keys_buffer(char* out_public, size_t public_size, char* out_private, size_t private_size)
{
	uint8_t public[crypto_sign_PUBLICKEYBYTES];
	uint8_t private[crypto_sign_SECRETKEYBYTES];
	crypto_sign_ed25519_keypair(public, private);

	char buffer[512];
	tf_base64_encode(public, sizeof(public), buffer, sizeof(buffer));
	snprintf(out_public, public_size, "%s.ed25519", buffer);

	tf_base64_encode(private, sizeof(private), buffer, sizeof(buffer));
	snprintf(out_private, private_size, "%s.ed25519", buffer);
}

void tf_ssb_get_private_key(tf_ssb_t* ssb, uint8_t* out_private, size_t private_size)
{
	memcpy(out_private, ssb->priv, tf_min(private_size, sizeof(ssb->priv)));
}

void tf_ssb_set_trace(tf_ssb_t* ssb, tf_trace_t* trace)
{
	ssb->trace = trace;
	sqlite3* db = tf_ssb_acquire_db_writer(ssb);
	if (trace && db)
	{
		tf_trace_sqlite(trace, db);
	}
	tf_ssb_release_db_writer(ssb, db);

	if (trace)
	{
		uv_mutex_lock(&ssb->db_readers_lock);
		for (int i = 0; i < ssb->db_readers_count; i++)
		{
			tf_trace_sqlite(trace, ssb->db_readers[i]);
		}
		uv_mutex_unlock(&ssb->db_readers_lock);
	}
}

tf_trace_t* tf_ssb_get_trace(tf_ssb_t* ssb)
{
	return ssb->trace;
}

JSContext* tf_ssb_get_context(tf_ssb_t* ssb)
{
	return ssb->context;
}

static void _tf_ssb_on_handle_close(uv_handle_t* handle)
{
	handle->data = NULL;
}

static void _tf_ssb_on_timer_close(uv_handle_t* handle)
{
	tf_free(handle->data);
}

void tf_ssb_destroy(tf_ssb_t* ssb)
{
	tf_printf("tf_ssb_destroy\n");
	ssb->shutting_down = true;

	if (ssb->connections_tracker)
	{
		tf_ssb_connections_destroy(ssb->connections_tracker);
		ssb->connections_tracker = NULL;
	}

	if (ssb->broadcast_listener.data && !uv_is_closing((uv_handle_t*)&ssb->broadcast_listener))
	{
		uv_close((uv_handle_t*)&ssb->broadcast_listener, _tf_ssb_on_handle_close);
	}

	if (ssb->broadcast_sender.data && !uv_is_closing((uv_handle_t*)&ssb->broadcast_sender))
	{
		uv_close((uv_handle_t*)&ssb->broadcast_sender, _tf_ssb_on_handle_close);
	}

	if (ssb->broadcast_timer.data && !uv_is_closing((uv_handle_t*)&ssb->broadcast_timer))
	{
		uv_close((uv_handle_t*)&ssb->broadcast_timer, _tf_ssb_on_handle_close);
	}

	if (ssb->broadcast_cleanup_timer.data && !uv_is_closing((uv_handle_t*)&ssb->broadcast_cleanup_timer))
	{
		uv_close((uv_handle_t*)&ssb->broadcast_cleanup_timer, _tf_ssb_on_handle_close);
	}

	if (ssb->trace_timer.data && !uv_is_closing((uv_handle_t*)&ssb->trace_timer))
	{
		uv_close((uv_handle_t*)&ssb->trace_timer, _tf_ssb_on_handle_close);
	}

	if (ssb->server.data && !uv_is_closing((uv_handle_t*)&ssb->server))
	{
		uv_close((uv_handle_t*)&ssb->server, _tf_ssb_on_handle_close);
	}

	for (int i = 0; i < ssb->timers_count; i++)
	{
		uv_close((uv_handle_t*)&ssb->timers[i]->timer, _tf_ssb_on_timer_close);
	}
	ssb->timers_count = 0;
	tf_free(ssb->timers);
	ssb->timers = NULL;

	tf_printf("Waiting for closes.\n");

	while (ssb->broadcast_listener.data || ssb->broadcast_sender.data || ssb->broadcast_timer.data || ssb->broadcast_cleanup_timer.data || ssb->trace_timer.data ||
		ssb->server.data || ssb->ref_count)
	{
		uv_run(ssb->loop, UV_RUN_ONCE);
	}

	tf_printf("Waiting for rpc.\n");

	while (ssb->rpc)
	{
		tf_ssb_rpc_callback_node_t* node = ssb->rpc;
		ssb->rpc = node->next;
		ssb->rpc_count--;
		if (node->cleanup)
		{
			node->cleanup(ssb, node->user_data);
			node->cleanup = NULL;
		}
		tf_free(node);
	}
	while (ssb->connections_changed)
	{
		tf_ssb_connections_changed_callback_node_t* node = ssb->connections_changed;
		ssb->connections_changed = node->next;
		ssb->connections_changed_count--;
		if (node->cleanup)
		{
			node->cleanup(ssb, node->user_data);
		}
		tf_free(node);
	}
	while (ssb->message_added)
	{
		tf_ssb_message_added_callback_node_t* node = ssb->message_added;
		ssb->message_added = node->next;
		ssb->message_added_count--;
		if (node->cleanup)
		{
			node->cleanup(ssb, node->user_data);
		}
		tf_free(node);
	}
	while (ssb->blob_want_added)
	{
		tf_ssb_blob_want_added_callback_node_t* node = ssb->blob_want_added;
		ssb->blob_want_added = node->next;
		ssb->blob_want_added_count--;
		if (node->cleanup)
		{
			node->cleanup(ssb, node->user_data);
		}
		tf_free(node);
	}
	while (ssb->broadcasts_changed)
	{
		tf_ssb_broadcasts_changed_callback_node_t* node = ssb->broadcasts_changed;
		ssb->broadcasts_changed = node->next;
		ssb->broadcasts_changed_count--;
		if (node->cleanup)
		{
			node->cleanup(ssb, node->user_data);
		}
		tf_free(node);
	}

	tf_printf("Closing connections.\n");
	tf_ssb_connection_t* connection = ssb->connections;
	while (connection)
	{
		tf_ssb_connection_t* next = connection->next;
		tf_ssb_connection_close(connection);
		connection = next;
	}
	tf_printf("Closed.\n");

	if (ssb->loop == &ssb->own_loop)
	{
		int r = uv_loop_close(ssb->loop);
		if (r != 0)
		{
			tf_printf("uv_loop_close: %s\n", uv_strerror(r));
		}
	}
	tf_printf("uv loop closed.\n");
	if (ssb->own_context)
	{
		tf_printf("closing ssb context\n");
		JS_FreeContext(ssb->context);
		JS_FreeRuntime(ssb->runtime);
		ssb->own_context = false;
	}
	if (ssb->db_writer)
	{
		sqlite3_close(ssb->db_writer);
		ssb->db_writer = NULL;
	}
	while (ssb->broadcasts)
	{
		tf_ssb_broadcast_t* broadcast = ssb->broadcasts;
		ssb->broadcasts = broadcast->next;
		ssb->broadcasts_count--;
		tf_free(broadcast);
	}
	for (int i = 0; i < k_debug_close_connection_count; i++)
	{
		for (int j = 0; j < k_debug_close_message_count; j++)
		{
			tf_free(ssb->debug_close[i].messages[j]);
		}
	}
	for (int i = 0; i < ssb->db_readers_count; i++)
	{
		sqlite3_close(ssb->db_readers[i]);
	}
	ssb->db_readers_count = 0;
	if (ssb->db_readers)
	{
		tf_free(ssb->db_readers);
		ssb->db_readers = NULL;
	}
	if (ssb->db_path)
	{
		tf_free((void*)ssb->db_path);
		ssb->db_path = NULL;
	}
	if (ssb->room_name)
	{
		tf_free(ssb->room_name);
		ssb->room_name = NULL;
	}

	if (ssb->connection_ref_count == 0)
	{
		uv_mutex_destroy(&ssb->db_readers_lock);
		uv_mutex_destroy(&ssb->db_writer_lock);

		tf_free(ssb);
	}
}

bool tf_ssb_is_shutting_down(tf_ssb_t* ssb)
{
	return ssb->shutting_down;
}

void tf_ssb_run(tf_ssb_t* ssb)
{
	uv_run(ssb->loop, UV_RUN_DEFAULT);
}

static void _tf_ssb_connection_finalizer(JSRuntime* runtime, JSValue value)
{
	tf_ssb_connection_t* connection = JS_GetOpaque(value, _connection_class_id);
	if (connection)
	{
		connection->object = JS_UNDEFINED;
		_tf_ssb_connection_destroy(connection, "object finalized");
	}
}

static void _tf_ssb_connection_process_message_async(uv_async_t* async)
{
	tf_ssb_connection_t* connection = async->data;
	if (_tf_ssb_connection_box_stream_recv(connection))
	{
		uv_async_send(&connection->async);
	}
}

tf_ssb_connection_t* tf_ssb_connection_create(tf_ssb_t* ssb, const char* host, const struct sockaddr_in* addr, const uint8_t* public_key)
{
	for (tf_ssb_connection_t* connection = ssb->connections; connection; connection = connection->next)
	{
		if (memcmp(connection->serverpub, public_key, k_id_bin_len) == 0 && connection->state != k_tf_ssb_state_invalid)
		{
			char id[k_id_base64_len];
			tf_ssb_id_bin_to_str(id, sizeof(id), public_key);
			tf_printf("Not connecting to %s:%d, because we are already connected to %s (state = %d).\n", host, ntohs(addr->sin_port), id, connection->state);
			return NULL;
		}
		else if (memcmp(ssb->pub, public_key, k_id_bin_len) == 0)
		{
			char id[k_id_base64_len];
			tf_ssb_id_bin_to_str(id, sizeof(id), public_key);
			tf_printf("Not connecting to %s:%d, because they appear to be ourselves %s.\n", host, ntohs(addr->sin_port), id);
			return NULL;
		}
	}

	JSContext* context = ssb->context;
	tf_ssb_connection_t* connection = tf_malloc(sizeof(tf_ssb_connection_t));
	ssb->connection_ref_count++;
	memset(connection, 0, sizeof(*connection));
	snprintf(connection->name, sizeof(connection->name), "cli%d", s_connection_index++);
	connection->ssb = ssb;
	connection->tcp.data = connection;
	connection->connect.data = connection;
	connection->send_request_number = 1;
	snprintf(connection->host, sizeof(connection->host), "%s", host);
	connection->port = ntohs(addr->sin_port);
	connection->async.data = connection;
	uv_async_init(ssb->loop, &connection->async, _tf_ssb_connection_process_message_async);

	connection->object = JS_NewObjectClass(ssb->context, _connection_class_id);
	JS_SetOpaque(connection->object, connection);
	char public_key_str[k_id_base64_len] = { 0 };
	if (tf_ssb_id_bin_to_str(public_key_str, sizeof(public_key_str), public_key))
	{
		JS_SetPropertyStr(context, connection->object, "id", JS_NewString(context, public_key_str));
		JS_SetPropertyStr(context, connection->object, "is_client", JS_TRUE);
	}

	memcpy(connection->serverpub, public_key, sizeof(connection->serverpub));

	uv_tcp_init(ssb->loop, &connection->tcp);
	int result = uv_tcp_connect(&connection->connect, &connection->tcp, (const struct sockaddr*)addr, _tf_ssb_connection_on_connect);
	if (result)
	{
		tf_printf("uv_tcp_connect(%s): %s\n", host, uv_strerror(result));
		connection->connect.data = NULL;
		_tf_ssb_connection_destroy(connection, "connect failed");
	}
	else
	{
		connection->next = ssb->connections;
		ssb->connections = connection;
		ssb->connections_count++;
		_tf_ssb_notify_connections_changed(ssb, k_tf_ssb_change_create, connection);
	}
	return connection;
}

static void _tf_ssb_connection_tunnel_callback(
	tf_ssb_connection_t* connection, uint8_t flags, int32_t request_number, JSValue args, const uint8_t* message, size_t size, void* user_data)
{
	tf_ssb_connection_t* tunnel = user_data;
	if (flags & k_ssb_rpc_flag_end_error)
	{
		tf_ssb_connection_rpc_send(connection, flags, -request_number, NULL, (const uint8_t*)"false", strlen("false"), NULL, NULL, NULL);
		tf_ssb_connection_close(tunnel);
	}
	else
	{
		_tf_ssb_connection_on_tcp_recv_internal(tunnel, message, size);
	}
}

tf_ssb_connection_t* tf_ssb_connection_tunnel_create(tf_ssb_t* ssb, const char* portal_id, int32_t request_number, const char* target_id)
{
	tf_ssb_connection_t* connection = tf_ssb_connection_get(ssb, portal_id);

	JSContext* context = ssb->context;
	tf_ssb_connection_t* tunnel = tf_malloc(sizeof(tf_ssb_connection_t));
	ssb->connection_ref_count++;
	memset(tunnel, 0, sizeof(*tunnel));
	snprintf(tunnel->name, sizeof(tunnel->name), "tun%d", s_tunnel_index++);
	tunnel->ssb = ssb;
	tunnel->tunnel_connection = connection;
	tunnel->tunnel_request_number = -request_number;
	tunnel->send_request_number = 1;
	tunnel->async.data = tunnel;
	uv_async_init(ssb->loop, &tunnel->async, _tf_ssb_connection_process_message_async);

	tunnel->object = JS_NewObjectClass(ssb->context, _connection_class_id);
	JS_SetOpaque(tunnel->object, tunnel);
	JS_SetPropertyStr(context, tunnel->object, "id", JS_NewString(context, target_id));
	JS_SetPropertyStr(context, tunnel->object, "is_client", JS_TRUE);

	tf_ssb_id_str_to_bin(tunnel->serverpub, target_id);

	tunnel->next = ssb->connections;
	ssb->connections = tunnel;
	ssb->connections_count++;
	_tf_ssb_notify_connections_changed(ssb, k_tf_ssb_change_create, tunnel);

	tf_ssb_connection_add_request(connection, request_number, "tunnel.connect", _tf_ssb_connection_tunnel_callback, NULL, tunnel, tunnel);
	if (request_number > 0)
	{
		tunnel->state = k_tf_ssb_state_connected;
		_tf_ssb_connection_client_send_hello(tunnel);
	}
	else
	{
		tunnel->state = k_tf_ssb_state_server_wait_hello;
	}

	return tunnel;
}

typedef struct _connect_t
{
	tf_ssb_t* ssb;
	uv_getaddrinfo_t req;
	char host[256];
	int port;
	uint8_t key[k_id_bin_len];
} connect_t;

static void _tf_on_connect_getaddrinfo(uv_getaddrinfo_t* addrinfo, int result, struct addrinfo* info)
{
	connect_t* connect = addrinfo->data;
	if (!connect->ssb->shutting_down)
	{
		if (result == 0 && info)
		{
			struct sockaddr_in addr = *(struct sockaddr_in*)info->ai_addr;
			addr.sin_port = htons(connect->port);
			tf_ssb_connection_create(connect->ssb, connect->host, &addr, connect->key);
		}
		else
		{
			tf_printf("getaddrinfo(%s) => %s\n", connect->host, uv_strerror(result));
		}
	}
	uv_freeaddrinfo(info);
	tf_ssb_unref(connect->ssb);
	tf_free(connect);
}

void tf_ssb_connect(tf_ssb_t* ssb, const char* host, int port, const uint8_t* key)
{
	if (ssb->shutting_down)
	{
		return;
	}
	connect_t* connect = tf_malloc(sizeof(connect_t));
	*connect = (connect_t) {
		.ssb = ssb,
		.port = port,
		.req.data = connect,
	};
	char id[k_id_base64_len] = { 0 };
	tf_ssb_id_bin_to_str(id, sizeof(id), key);
	tf_ssb_connections_store(ssb->connections_tracker, host, port, id);
	snprintf(connect->host, sizeof(connect->host), "%s", host);
	memcpy(connect->key, key, k_id_bin_len);
	tf_ssb_ref(ssb);
	int r = uv_getaddrinfo(ssb->loop, &connect->req, _tf_on_connect_getaddrinfo, host, NULL, &(struct addrinfo) { .ai_family = AF_INET });
	if (r < 0)
	{
		tf_printf("uv_getaddrinfo: %s\n", uv_strerror(r));
		tf_free(connect);
		tf_ssb_unref(ssb);
	}
}

void tf_ssb_connection_close(tf_ssb_connection_t* connection)
{
	_tf_ssb_connection_close(connection, "tf_ssb_connection_close");
}

static void _tf_ssb_on_connection(uv_stream_t* stream, int status)
{
	tf_ssb_t* ssb = stream->data;
	if (status < 0)
	{
		tf_printf("uv_listen failed: %s\n", uv_strerror(status));
		return;
	}

	tf_ssb_connection_t* connection = tf_malloc(sizeof(tf_ssb_connection_t));
	ssb->connection_ref_count++;
	memset(connection, 0, sizeof(*connection));
	snprintf(connection->name, sizeof(connection->name), "srv%d", s_connection_index++);
	connection->ssb = ssb;
	connection->tcp.data = connection;
	connection->send_request_number = 1;
	connection->async.data = connection;
	uv_async_init(ssb->loop, &connection->async, _tf_ssb_connection_process_message_async);

	connection->object = JS_NewObjectClass(ssb->context, _connection_class_id);
	JS_SetOpaque(connection->object, connection);

	if (uv_tcp_init(ssb->loop, &connection->tcp) != 0)
	{
		_tf_ssb_connection_destroy(connection, "init failed");
		return;
	}

	if (uv_accept(stream, (uv_stream_t*)&connection->tcp) != 0)
	{
		_tf_ssb_connection_destroy(connection, "accept failed");
		return;
	}

	struct sockaddr_storage addr = { 0 };
	int size = sizeof(addr);
	if (uv_tcp_getpeername(&connection->tcp, (struct sockaddr*)&addr, &size) == 0)
	{
		uv_ip_name((struct sockaddr*)&addr, connection->host, sizeof(connection->host));
		connection->port = ntohs(((struct sockaddr_in*)&addr)->sin_port);
	}

	connection->next = ssb->connections;
	ssb->connections = connection;
	ssb->connections_count++;
	_tf_ssb_notify_connections_changed(ssb, k_tf_ssb_change_create, connection);

	connection->state = k_tf_ssb_state_server_wait_hello;
	_tf_ssb_connection_read_start(connection);
}

static void _tf_ssb_send_broadcast(tf_ssb_t* ssb, struct sockaddr_in* address, struct sockaddr_in* netmask)
{
	struct sockaddr server_addr;
	int len = (int)sizeof(server_addr);
	int r = uv_tcp_getsockname(&ssb->server, &server_addr, &len);
	if (r != 0)
	{
		tf_printf("Unable to get server's address: %s.\n", uv_strerror(r));
	}
	else if (server_addr.sa_family != AF_INET)
	{
		tf_printf("Unexpected address family: %d\n", server_addr.sa_family);
	}

	char address_str[256];
	if (uv_ip4_name(address, address_str, sizeof(address_str)) != 0)
	{
		tf_printf("Unable to convert address to string.\n");
	}

	char fullid[k_id_base64_len];
	tf_base64_encode(ssb->pub, sizeof(ssb->pub), fullid, sizeof(fullid));

	char message[512];
	snprintf(message, sizeof(message), "net:%s:%d~shs:%s", address_str, ntohs(((struct sockaddr_in*)&server_addr)->sin_port), fullid);

	uv_buf_t buf = { .base = message, .len = strlen(message) };

	struct sockaddr_in broadcast_addr = { 0 };
	broadcast_addr.sin_family = AF_INET;
	broadcast_addr.sin_port = htons(8008);
	broadcast_addr.sin_addr.s_addr = (address->sin_addr.s_addr & netmask->sin_addr.s_addr) | (INADDR_BROADCAST & ~netmask->sin_addr.s_addr);
	r = uv_udp_try_send(&ssb->broadcast_sender, &buf, 1, (struct sockaddr*)&broadcast_addr);
	if (r < 0)
	{
		char broadcast_str[256] = { 0 };
		uv_ip4_name(&broadcast_addr, broadcast_str, sizeof(broadcast_str));
		tf_printf("failed to send broadcast for %s via %s (%d): %s\n", address_str, broadcast_str, r, uv_strerror(r));
	}
}

typedef struct _seeds_t
{
	char** seeds;
	int seeds_count;
} seeds_t;

static void _tf_ssb_update_seed_callback(void* arg, ares_status_t status, size_t timeouts, const ares_dns_record_t* record)
{
	seeds_t* seeds = arg;
	for (int i = 0; i < (int)ares_dns_record_rr_cnt(record, ARES_SECTION_ANSWER); i++)
	{
		const ares_dns_rr_t* rr = ares_dns_record_rr_get_const(record, ARES_SECTION_ANSWER, i);
		size_t len = 0;
		const unsigned char* str = ares_dns_rr_get_bin(rr, ARES_RR_TXT_DATA, &len);
		seeds->seeds = tf_resize_vec(seeds->seeds, sizeof(char*) * (seeds->seeds_count + 1));
		seeds->seeds[seeds->seeds_count++] = tf_strdup((const char*)str);
	}
}

static void _tf_ssb_update_seeds_work(tf_ssb_t* ssb, void* user_data)
{
	if (ares_library_init(0) == ARES_SUCCESS)
	{
		ares_channel channel;
		struct ares_options options = { .evsys = ARES_EVSYS_DEFAULT };
		int result = ares_init_options(&channel, &options, ARES_OPT_EVENT_THREAD);
		if (result == ARES_SUCCESS)
		{
			if (ares_query_dnsrec(channel, ssb->seeds_host, ARES_CLASS_IN, ARES_REC_TYPE_TXT, _tf_ssb_update_seed_callback, user_data, NULL) == ARES_SUCCESS)
			{
				ares_queue_wait_empty(channel, -1);
			}
			ares_destroy(channel);
		}
		ares_library_cleanup();
	}
}

static void _tf_ssb_update_seeds_after_work(tf_ssb_t* ssb, int status, void* user_data)
{
	seeds_t* seeds = user_data;
	for (int i = 0; i < seeds->seeds_count; i++)
	{
		tf_ssb_broadcast_t broadcast = { 0 };
		if (_tf_ssb_parse_broadcast(seeds->seeds[i], &broadcast))
		{
			_tf_ssb_add_broadcast(ssb, &broadcast);
		}
		tf_free(seeds->seeds[i]);
	}
	tf_free(seeds->seeds);
	tf_free(seeds);
}

static void _tf_ssb_broadcast_timer(uv_timer_t* timer)
{
	tf_ssb_t* ssb = timer->data;
	uv_interface_address_t* info = NULL;
	int count = 0;
	if (uv_interface_addresses(&info, &count) == 0)
	{
		for (int i = 0; i < count; i++)
		{
			if (!info[i].is_internal && info[i].address.address4.sin_family == AF_INET)
			{
				_tf_ssb_send_broadcast(ssb, &info[i].address.address4, &info[i].netmask.netmask4);
			}
		}
		uv_free_interface_addresses(info, count);
	}

	seeds_t* seeds = tf_malloc(sizeof(seeds_t));
	*seeds = (seeds_t) { 0 };

	if (*ssb->seeds_host)
	{
		tf_ssb_run_work(ssb, _tf_ssb_update_seeds_work, _tf_ssb_update_seeds_after_work, seeds);
	}
}

int tf_ssb_server_open(tf_ssb_t* ssb, int port)
{
	if (ssb->server.data)
	{
		tf_printf("Already listening.\n");
		return 0;
	}

	ssb->server.data = ssb;
	if (uv_tcp_init(ssb->loop, &ssb->server) != 0)
	{
		tf_printf("uv_tcp_init failed\n");
		return 0;
	}

	struct sockaddr_in addr = { 0 };
	addr.sin_family = AF_INET;
	addr.sin_port = htons(port);
	addr.sin_addr.s_addr = INADDR_ANY;
	int status = uv_tcp_bind(&ssb->server, (struct sockaddr*)&addr, 0);
	if (status != 0)
	{
		tf_printf("%s:%d: uv_tcp_bind failed: %s\n", __FILE__, __LINE__, uv_strerror(status));
		return 0;
	}

	status = uv_listen((uv_stream_t*)&ssb->server, SOMAXCONN, _tf_ssb_on_connection);
	if (status != 0)
	{
		tf_printf("uv_listen failed: %s\n", uv_strerror(status));
		/* TODO: cleanup */
		return 0;
	}

	struct sockaddr_storage name = { 0 };
	int size = (int)sizeof(name);
	status = uv_tcp_getsockname(&ssb->server, (struct sockaddr*)&name, &size);
	int assigned_port = ntohs(((struct sockaddr_in*)&name)->sin_port);
	return status == 0 ? assigned_port : 0;
}

void tf_ssb_server_close(tf_ssb_t* ssb)
{
	if (ssb->server.data && !uv_is_closing((uv_handle_t*)&ssb->server))
	{
		uv_close((uv_handle_t*)&ssb->server, _tf_ssb_on_handle_close);
	}

	uv_timer_stop(&ssb->broadcast_timer);
	tf_printf("Stopped broadcasts.\n");
}

bool tf_ssb_whoami(tf_ssb_t* ssb, char* out_id, size_t out_id_size)
{
	return tf_ssb_id_bin_to_str(out_id, out_id_size, ssb->pub);
}

static bool _tf_ssb_parse_broadcast(const char* in_broadcast, tf_ssb_broadcast_t* out_broadcast)
{
	char public_key_str[45] = { 0 };
	int port = 0;
	static_assert(sizeof(out_broadcast->host) == 256, "host field size");
	if (sscanf(in_broadcast, "net:%255[0-9A-Za-z.-]:%d~shs:%44s", out_broadcast->host, &port, public_key_str) == 3)
	{
		out_broadcast->addr.sin_family = AF_INET;
		out_broadcast->addr.sin_port = htons((uint16_t)port);
		int r = tf_base64_decode(public_key_str, strlen(public_key_str), out_broadcast->pub, crypto_sign_PUBLICKEYBYTES);
		return r != -1;
	}
	else if (strncmp(in_broadcast, "ws:", 3) == 0)
	{
		tf_printf("Unsupported broadcast: %s\n", in_broadcast);
	}
	return false;
}

void tf_ssb_connect_str(tf_ssb_t* ssb, const char* address)
{
	tf_ssb_broadcast_t broadcast = { 0 };
	if (_tf_ssb_parse_broadcast(address, &broadcast))
	{
		tf_ssb_connect(ssb, broadcast.host, ntohs(broadcast.addr.sin_port), broadcast.pub);
	}
	else
	{
		tf_printf("Unable to parse: %s\n", address);
	}
}

static void _tf_ssb_on_broadcast_listener_alloc(uv_handle_t* handle, size_t suggested_size, uv_buf_t* buf)
{
	buf->base = tf_malloc(suggested_size);
	buf->len = suggested_size;
}

static void _tf_ssb_notify_broadcasts_changed(tf_ssb_t* ssb)
{
	tf_ssb_broadcasts_changed_callback_node_t* next = NULL;
	for (tf_ssb_broadcasts_changed_callback_node_t* node = ssb->broadcasts_changed; node; node = next)
	{
		next = node->next;
		if (node->callback)
		{
			tf_trace_begin(ssb->trace, "broadcasts changed");
			node->callback(ssb, node->user_data);
			tf_trace_end(ssb->trace);
		}
	}
}

static void _tf_ssb_add_broadcast(tf_ssb_t* ssb, const tf_ssb_broadcast_t* broadcast)
{
	if (memcmp(broadcast->pub, ssb->pub, sizeof(ssb->pub)) == 0)
	{
		return;
	}

	if (broadcast->tunnel_connection)
	{
		for (tf_ssb_broadcast_t* node = ssb->broadcasts; node; node = node->next)
		{
			if (node->tunnel_connection == broadcast->tunnel_connection && memcmp(node->pub, broadcast->pub, sizeof(node->pub)) == 0)
			{
				node->mtime = time(NULL);
				return;
			}
		}
	}
	else
	{
		for (tf_ssb_broadcast_t* node = ssb->broadcasts; node; node = node->next)
		{
			if (node->addr.sin_family == broadcast->addr.sin_family && node->addr.sin_port == broadcast->addr.sin_port &&
				node->addr.sin_addr.s_addr == broadcast->addr.sin_addr.s_addr && memcmp(node->pub, broadcast->pub, sizeof(node->pub)) == 0)
			{
				node->mtime = time(NULL);
				return;
			}
		}

		char key[k_id_base64_len];
		if (tf_ssb_id_bin_to_str(key, sizeof(key), broadcast->pub))
		{
			tf_printf("Received new broadcast: host=%s, pub=%s.\n", broadcast->host, key);
		}
	}

	tf_ssb_broadcast_t* node = tf_malloc(sizeof(tf_ssb_broadcast_t));
	*node = *broadcast;
	node->next = ssb->broadcasts;
	node->ctime = time(NULL);
	node->mtime = node->ctime;
	ssb->broadcasts = node;
	ssb->broadcasts_count++;

	_tf_ssb_notify_broadcasts_changed(ssb);
}

static void _tf_ssb_on_broadcast_listener_recv(uv_udp_t* handle, ssize_t nread, const uv_buf_t* buf, const struct sockaddr* addr, unsigned flags)
{
	if (nread <= 0)
	{
		tf_free(buf->base);
		return;
	}

	tf_ssb_t* ssb = handle->data;
	((char*)buf->base)[nread] = '\0';

	const char* k_delim = ";";
	char* state = NULL;
	char* entry = strtok_r(buf->base, k_delim, &state);
	while (entry)
	{
		tf_ssb_broadcast_t broadcast = { 0 };
		if (_tf_ssb_parse_broadcast(entry, &broadcast))
		{
			_tf_ssb_add_broadcast(ssb, &broadcast);
		}
		entry = strtok_r(NULL, k_delim, &state);
	}
	tf_free(buf->base);
}

void tf_ssb_visit_broadcasts(
	tf_ssb_t* ssb, void (*callback)(const char* host, const struct sockaddr_in* addr, tf_ssb_connection_t* tunnel, const uint8_t* pub, void* user_data), void* user_data)
{
	time_t now = time(NULL);
	tf_ssb_broadcast_t* next = NULL;
	for (tf_ssb_broadcast_t* node = ssb->broadcasts; node; node = next)
	{
		next = node->next;
		if (node->mtime - now < 60)
		{
			tf_trace_begin(ssb->trace, "broadcast");
			callback(node->host, &node->addr, node->tunnel_connection, node->pub, user_data);
			tf_trace_end(ssb->trace);
		}
	}
}

static void _tf_ssb_broadcast_cleanup_timer(uv_timer_t* timer)
{
	tf_ssb_t* ssb = timer->data;
	int modified = 0;
	time_t now = time(NULL);
	for (tf_ssb_broadcast_t** it = &ssb->broadcasts; *it;)
	{
		if (!(*it)->tunnel_connection && (*it)->mtime < now - 10)
		{
			tf_ssb_broadcast_t* node = *it;
			*it = node->next;
			tf_free(node);
			ssb->broadcasts_count--;
			modified++;
		}
		else
		{
			it = &(*it)->next;
		}
	}

	if (modified)
	{
		_tf_ssb_notify_broadcasts_changed(ssb);
	}
}

void tf_ssb_broadcast_listener_start(tf_ssb_t* ssb, bool linger)
{
	if (ssb->broadcast_listener.data)
	{
		return;
	}

	ssb->broadcast_listener.data = ssb;
	uv_udp_init(ssb->loop, &ssb->broadcast_listener);

	struct sockaddr_in addr = { 0 };
	addr.sin_family = AF_INET;
	addr.sin_port = htons(8008);
	addr.sin_addr.s_addr = INADDR_ANY;
	int result = uv_udp_bind(&ssb->broadcast_listener, (const struct sockaddr*)&addr, UV_UDP_REUSEADDR);
	if (result != 0)
	{
		tf_printf("bind: %s\n", uv_strerror(result));
	}

	result = uv_udp_recv_start(&ssb->broadcast_listener, _tf_ssb_on_broadcast_listener_alloc, _tf_ssb_on_broadcast_listener_recv);
	if (result != 0)
	{
		tf_printf("uv_udp_recv_start: %s\n", uv_strerror(result));
	}

	if (!linger)
	{
		uv_unref((uv_handle_t*)&ssb->broadcast_listener);
	}

	ssb->broadcast_cleanup_timer.data = ssb;
	uv_timer_init(ssb->loop, &ssb->broadcast_cleanup_timer);
	uv_timer_start(&ssb->broadcast_cleanup_timer, _tf_ssb_broadcast_cleanup_timer, 2000, 2000);
}

void tf_ssb_broadcast_sender_start(tf_ssb_t* ssb)
{
	if (ssb->broadcast_sender.data)
	{
		return;
	}

	ssb->broadcast_sender.data = ssb;
	uv_udp_init(ssb->loop, &ssb->broadcast_sender);
	struct sockaddr_in broadcast_from = {
		.sin_family = AF_INET,
		.sin_addr.s_addr = INADDR_ANY,
	};
	uv_udp_bind(&ssb->broadcast_sender, (struct sockaddr*)&broadcast_from, 0);
	uv_udp_set_broadcast(&ssb->broadcast_sender, 1);

	tf_printf("Starting broadcasts.\n");
	uv_timer_start(&ssb->broadcast_timer, _tf_ssb_broadcast_timer, 2000, 2000);
}

tf_ssb_connection_t* tf_ssb_connection_get(tf_ssb_t* ssb, const char* id)
{
	uint8_t pub[k_id_bin_len] = { 0 };
	tf_ssb_id_str_to_bin(pub, id);
	for (tf_ssb_connection_t* connection = ssb->connections; connection; connection = connection->next)
	{
		if (connection->tunnel_connection)
		{
			continue;
		}

		if (memcmp(connection->serverpub, pub, k_id_bin_len) == 0)
		{
			return connection;
		}
		else if (memcmp(ssb->pub, pub, k_id_bin_len) == 0)
		{
			return connection;
		}
	}
	return NULL;
}

const char** tf_ssb_get_connection_ids(tf_ssb_t* ssb)
{
	int count = 0;
	for (tf_ssb_connection_t* connection = ssb->connections; connection; connection = connection->next)
	{
		if (connection->state == k_tf_ssb_state_verified || connection->state == k_tf_ssb_state_server_verified)
		{
			count++;
		}
	}

	char* buffer = tf_malloc(sizeof(char*) * (count + 1) + k_id_base64_len * count);
	char** array = (char**)buffer;
	char* strings = buffer + sizeof(char*) * (count + 1);
	int i = 0;
	for (tf_ssb_connection_t* connection = ssb->connections; connection; connection = connection->next)
	{
		if (connection->state == k_tf_ssb_state_verified || connection->state == k_tf_ssb_state_server_verified)
		{
			char* write_pos = strings + k_id_base64_len * i;
			tf_ssb_id_bin_to_str(write_pos, k_id_base64_len, connection->serverpub);
			array[i++] = write_pos;
		}
	}
	array[i] = NULL;
	return (const char**)array;
}

int tf_ssb_get_connections(tf_ssb_t* ssb, tf_ssb_connection_t** out_connections, int out_connections_count)
{
	int i = 0;
	for (tf_ssb_connection_t* connection = ssb->connections; connection && i < out_connections_count; connection = connection->next)
	{
		out_connections[i++] = connection;
	}
	return i;
}

void tf_ssb_add_broadcasts_changed_callback(tf_ssb_t* ssb, tf_ssb_broadcasts_changed_callback_t* callback, tf_ssb_callback_cleanup_t* cleanup, void* user_data)
{
	tf_ssb_broadcasts_changed_callback_node_t* node = tf_malloc(sizeof(tf_ssb_broadcasts_changed_callback_node_t));
	*node = (tf_ssb_broadcasts_changed_callback_node_t) {
		.callback = callback,
		.cleanup = cleanup,
		.user_data = user_data,
		.next = ssb->broadcasts_changed,
	};
	ssb->broadcasts_changed = node;
	ssb->broadcasts_changed_count++;
}

void tf_ssb_remove_broadcasts_changed_callback(tf_ssb_t* ssb, tf_ssb_broadcasts_changed_callback_t* callback, void* user_data)
{
	tf_ssb_broadcasts_changed_callback_node_t** it = &ssb->broadcasts_changed;
	while (*it)
	{
		if ((*it)->callback == callback && (*it)->user_data == user_data)
		{
			tf_ssb_broadcasts_changed_callback_node_t* node = *it;
			*it = node->next;
			ssb->broadcasts_changed_count--;
			if (node->cleanup)
			{
				node->cleanup(ssb, node->user_data);
			}
			tf_free(node);
		}
		else
		{
			it = &(*it)->next;
		}
	}
}

void tf_ssb_add_connections_changed_callback(tf_ssb_t* ssb, tf_ssb_connections_changed_callback_t* callback, tf_ssb_callback_cleanup_t* cleanup, void* user_data)
{
	tf_ssb_connections_changed_callback_node_t* node = tf_malloc(sizeof(tf_ssb_connections_changed_callback_node_t));
	*node = (tf_ssb_connections_changed_callback_node_t) {
		.callback = callback,
		.cleanup = cleanup,
		.user_data = user_data,
		.next = ssb->connections_changed,
	};
	ssb->connections_changed = node;
	ssb->connections_changed_count++;
}

void tf_ssb_remove_connections_changed_callback(tf_ssb_t* ssb, tf_ssb_connections_changed_callback_t* callback, void* user_data)
{
	tf_ssb_connections_changed_callback_node_t** it = &ssb->connections_changed;
	while (*it)
	{
		if ((*it)->callback == callback && (*it)->user_data == user_data)
		{
			tf_ssb_connections_changed_callback_node_t* node = *it;
			*it = node->next;
			ssb->connections_changed_count--;
			if (node->cleanup)
			{
				node->cleanup(ssb, node->user_data);
			}
			tf_free(node);
		}
		else
		{
			it = &(*it)->next;
		}
	}
}

void tf_ssb_add_rpc_callback(tf_ssb_t* ssb, const char** name, tf_ssb_rpc_callback_t* callback, tf_ssb_callback_cleanup_t* cleanup, void* user_data)
{
	size_t name_len = 0;
	int name_count = 0;
	for (int i = 0; name[i]; i++)
	{
		name_count++;
		name_len += strlen(name[i]) + 1;
	}
	tf_ssb_rpc_callback_node_t* node = tf_malloc(sizeof(tf_ssb_rpc_callback_node_t) + (name_count + 1) * sizeof(const char*) + name_len + name_len + 3);
	*node = (tf_ssb_rpc_callback_node_t) {
		.name = (const char**)(node + 1),
		.flattened_name = (const char*)(node + 1) + (name_count + 1) * sizeof(const char*) + name_len,
		.callback = callback,
		.cleanup = cleanup,
		.user_data = user_data,
		.next = ssb->rpc,
	};
	char* p = (char*)(node + 1) + (name_count + 1) * sizeof(const char*);
	for (int i = 0; i < name_count; i++)
	{
		size_t len = strlen(name[i]);
		memcpy(p, name[i], len + 1);
		node->name[i] = p;
		p += len + 1;
	}
	char* flattened_name = (char*)node->flattened_name;
	for (int i = 0; i < name_count; i++)
	{
		size_t length = strlen(name[i]);
		memcpy(flattened_name, name[i], length);
		flattened_name += length;
		if (i != name_count - 1)
		{
			*flattened_name++ = '.';
		}
	}
	*flattened_name++ = '(';
	*flattened_name++ = ')';
	*flattened_name++ = '\0';
	node->name[name_count] = NULL;
	ssb->rpc = node;
	ssb->rpc_count++;
}

JSContext* tf_ssb_connection_get_context(tf_ssb_connection_t* connection)
{
	return connection->ssb->context;
}

tf_ssb_t* tf_ssb_connection_get_ssb(tf_ssb_connection_t* connection)
{
	return connection->ssb;
}

int32_t tf_ssb_connection_next_request_number(tf_ssb_connection_t* connection)
{
	return connection->send_request_number++;
}

JSClassID tf_ssb_get_connection_class_id()
{
	return _connection_class_id;
}

JSValue tf_ssb_connection_get_object(tf_ssb_connection_t* connection)
{
	return connection ? connection->object : JS_UNDEFINED;
}

void tf_ssb_add_message_added_callback(
	tf_ssb_t* ssb, void (*callback)(tf_ssb_t* ssb, const char* id, void* user_data), void (*cleanup)(tf_ssb_t* ssb, void* user_data), void* user_data)
{
	tf_ssb_message_added_callback_node_t* node = tf_malloc(sizeof(tf_ssb_message_added_callback_node_t));
	*node = (tf_ssb_message_added_callback_node_t) {
		.callback = callback,
		.cleanup = cleanup,
		.user_data = user_data,
		.next = ssb->message_added,
	};
	ssb->message_added = node;
	ssb->message_added_count++;
}

void tf_ssb_remove_message_added_callback(tf_ssb_t* ssb, tf_ssb_message_added_callback_t* callback, void* user_data)
{
	tf_ssb_message_added_callback_node_t** it = &ssb->message_added;
	while (*it)
	{
		if ((*it)->callback == callback && (*it)->user_data == user_data)
		{
			tf_ssb_message_added_callback_node_t* node = *it;
			*it = node->next;
			ssb->message_added_count--;
			if (node->cleanup)
			{
				node->cleanup(ssb, node->user_data);
			}
			tf_free(node);
		}
		else
		{
			it = &(*it)->next;
		}
	}
}

void tf_ssb_notify_blob_stored(tf_ssb_t* ssb, const char* id)
{
	ssb->blobs_stored++;
}

void tf_ssb_notify_message_added(tf_ssb_t* ssb, const char* id, JSValue message_keys)
{
	tf_ssb_message_added_callback_node_t* next = NULL;
	ssb->messages_stored++;
	for (tf_ssb_message_added_callback_node_t* node = ssb->message_added; node; node = next)
	{
		next = node->next;
		tf_trace_begin(ssb->trace, "message added callback");
		node->callback(ssb, id, node->user_data);
		tf_trace_end(ssb->trace);
	}

	JSContext* context = ssb->context;
	if (!JS_IsUndefined(message_keys))
	{
		JSValue message = JS_GetPropertyStr(context, message_keys, "value");
		JSValue author = JS_GetPropertyStr(context, message, "author");
		const char* author_string = JS_ToCString(context, author);

		for (tf_ssb_connection_t* connection = ssb->connections; connection; connection = connection->next)
		{
			if (!connection->message_requests_count)
			{
				continue;
			}
			tf_ssb_connection_message_request_t* message_request =
				bsearch(author_string, connection->message_requests, connection->message_requests_count, sizeof(tf_ssb_connection_message_request_t), _message_request_compare);
			if (message_request)
			{
				tf_ssb_connection_rpc_send_json(
					connection, k_ssb_rpc_flag_stream, message_request->request_number, NULL, message_request->keys ? message_keys : message, NULL, NULL, NULL);
			}
		}

		JS_FreeCString(context, author_string);
		JS_FreeValue(context, author);
		JS_FreeValue(context, message);
	}
}

void tf_ssb_add_blob_want_added_callback(
	tf_ssb_t* ssb, void (*callback)(tf_ssb_t* ssb, const char* id, void* user_data), void (*cleanup)(tf_ssb_t* ssb, void* user_data), void* user_data)
{
	tf_ssb_blob_want_added_callback_node_t* node = tf_malloc(sizeof(tf_ssb_blob_want_added_callback_node_t));
	*node = (tf_ssb_blob_want_added_callback_node_t) {
		.callback = callback,
		.cleanup = cleanup,
		.user_data = user_data,
		.next = ssb->blob_want_added,
	};
	ssb->blob_want_added = node;
	ssb->blob_want_added_count++;
}

void tf_ssb_remove_blob_want_added_callback(tf_ssb_t* ssb, tf_ssb_blob_want_added_callback_t* callback, void* user_data)
{
	tf_ssb_blob_want_added_callback_node_t** it = &ssb->blob_want_added;
	while (*it)
	{
		if ((*it)->callback == callback && (*it)->user_data == user_data)
		{
			tf_ssb_blob_want_added_callback_node_t* node = *it;
			*it = node->next;
			ssb->blob_want_added_count--;
			if (node->cleanup)
			{
				node->cleanup(ssb, node->user_data);
			}
			tf_free(node);
		}
		else
		{
			it = &(*it)->next;
		}
	}
}

void tf_ssb_notify_blob_want_added(tf_ssb_t* ssb, const char* id)
{
	tf_ssb_blob_want_added_callback_node_t* next = NULL;
	for (tf_ssb_blob_want_added_callback_node_t* node = ssb->blob_want_added; node; node = next)
	{
		next = node->next;
		tf_trace_begin(ssb->trace, "blob want added callback");
		node->callback(ssb, id, node->user_data);
		tf_trace_end(ssb->trace);
	}
}

void tf_ssb_connection_add_room_attendant(tf_ssb_connection_t* connection, const char* id)
{
	tf_ssb_broadcast_t broadcast = {
		.tunnel_connection = connection,
	};
	tf_ssb_id_str_to_bin(broadcast.pub, id);
	_tf_ssb_add_broadcast(connection->ssb, &broadcast);
}

void tf_ssb_connection_remove_room_attendant(tf_ssb_connection_t* connection, const char* id)
{
	uint8_t pub[k_id_bin_len] = { 0 };
	tf_ssb_id_str_to_bin(pub, id);

	int modified = 0;
	for (tf_ssb_broadcast_t** it = &connection->ssb->broadcasts; *it;)
	{
		if ((*it)->tunnel_connection == connection && memcmp((*it)->pub, pub, k_id_bin_len) == 0)
		{
			tf_ssb_broadcast_t* node = *it;
			*it = node->next;
			tf_free(node);
			connection->ssb->broadcasts_count--;
			modified++;
		}
		else
		{
			it = &(*it)->next;
		}
	}

	if (modified)
	{
		_tf_ssb_notify_broadcasts_changed(connection->ssb);
	}
}

bool tf_ssb_connection_is_attendant(tf_ssb_connection_t* connection)
{
	return connection->is_attendant;
}

int32_t tf_ssb_connection_get_attendant_request_number(tf_ssb_connection_t* connection)
{
	return connection->attendant_request_number;
}

void tf_ssb_connection_set_attendant(tf_ssb_connection_t* connection, bool attendant, int request_number)
{
	connection->is_attendant = attendant;
	connection->attendant_request_number = request_number;
	_tf_ssb_notify_broadcasts_changed(connection->ssb);
}

void tf_ssb_connection_clear_room_attendants(tf_ssb_connection_t* connection)
{
	int modified = 0;
	for (tf_ssb_broadcast_t** it = &connection->ssb->broadcasts; *it;)
	{
		if ((*it)->tunnel_connection == connection)
		{
			tf_ssb_broadcast_t* node = *it;
			*it = node->next;
			tf_free(node);
			connection->ssb->broadcasts_count--;
			modified++;
		}
		else
		{
			it = &(*it)->next;
		}
	}

	if (modified)
	{
		_tf_ssb_notify_broadcasts_changed(connection->ssb);
	}
}

tf_ssb_blob_wants_t* tf_ssb_connection_get_blob_wants_state(tf_ssb_connection_t* connection)
{
	return connection ? &connection->blob_wants : NULL;
}

typedef struct _store_t
{
	tf_ssb_t* ssb;
	tf_ssb_verify_strip_store_callback_t* callback;
	void* user_data;
	bool verified;
	bool stored;
	char id[crypto_hash_sha256_BYTES * 2 + 1];
} store_t;

static void _tf_ssb_verify_strip_and_store_finish(store_t* store)
{
	if (store->callback)
	{
		store->callback(store->id, store->verified, store->stored, store->user_data);
	}
	tf_free(store);
}

static void _tf_ssb_verify_strip_and_store_callback(const char* id, bool stored, void* user_data)
{
	store_t* store = user_data;
	store->stored = stored;
	_tf_ssb_verify_strip_and_store_finish(store);
}

void tf_ssb_verify_strip_and_store_message(tf_ssb_t* ssb, JSValue value, tf_ssb_verify_strip_store_callback_t* callback, void* user_data)
{
	JSContext* context = tf_ssb_get_context(ssb);
	store_t* async = tf_malloc(sizeof(store_t));
	*async = (store_t) {
		.ssb = ssb,
		.callback = callback,
		.user_data = user_data,
	};
	char signature[crypto_sign_BYTES + 128] = { 0 };
	int flags = 0;
	if (tf_ssb_verify_and_strip_signature(context, value, async->id, sizeof(async->id), signature, sizeof(signature), &flags))
	{
		async->verified = true;
		tf_ssb_db_store_message(ssb, context, async->id, value, signature, flags, _tf_ssb_verify_strip_and_store_callback, async);
	}
	else
	{
		_tf_ssb_verify_strip_and_store_finish(async);
	}
}

bool tf_ssb_connection_get_sent_clock(tf_ssb_connection_t* connection)
{
	return connection->sent_clock;
}

void tf_ssb_connection_set_sent_clock(tf_ssb_connection_t* connection, bool sent_clock)
{
	connection->sent_clock = sent_clock;
}

int32_t tf_ssb_connection_get_ebt_request_number(tf_ssb_connection_t* connection)
{
	return connection->ebt_request_number;
}

void tf_ssb_connection_set_ebt_request_number(tf_ssb_connection_t* connection, int32_t request_number)
{
	connection->ebt_request_number = request_number;
}

JSValue tf_ssb_get_disconnection_debug(tf_ssb_t* ssb, JSContext* context)
{
	JSValue result = JS_NewObject(context);
	JSValue disconnections = JS_NewArray(context);
	for (int i = 0; i < k_debug_close_connection_count; i++)
	{
		JSValue disconnection = JS_NewObject(context);
		if (*ssb->debug_close[i].id)
		{
			JS_SetPropertyStr(context, disconnection, "id", JS_NewString(context, ssb->debug_close[i].id));
			if (*ssb->debug_close[i].tunnel)
			{
				JS_SetPropertyStr(context, disconnection, "tunnel", JS_NewString(context, ssb->debug_close[i].tunnel));
			}
			JS_SetPropertyStr(context, disconnection, "reason", JS_NewString(context, ssb->debug_close[i].reason));
			JSValue messages = JS_NewArray(context);
			for (int j = 0; j < k_debug_close_message_count; j++)
			{
				if (ssb->debug_close[i].messages[j])
				{
					JSValue message = JS_NewObject(context);
					JS_SetPropertyStr(context, message, "direction", JS_NewString(context, ssb->debug_close[i].messages[j]->outgoing ? "out" : "in"));
					JS_SetPropertyStr(context, message, "flags", JS_NewInt32(context, ssb->debug_close[i].messages[j]->flags));
					JS_SetPropertyStr(context, message, "request_number", JS_NewInt32(context, ssb->debug_close[i].messages[j]->request_number));
					JS_SetPropertyStr(context, message, "timestamp", JS_NewFloat64(context, ssb->debug_close[i].messages[j]->timestamp));
					JS_SetPropertyStr(
						context, message, "payload", JS_NewStringLen(context, (const char*)ssb->debug_close[i].messages[j]->data, ssb->debug_close[i].messages[j]->size));
					JS_SetPropertyUint32(context, messages, j, message);
				}
			}
			JS_SetPropertyStr(context, disconnection, "messages", messages);
		}
		JS_SetPropertyUint32(context, disconnections, i, disconnection);
	}
	JS_SetPropertyStr(context, result, "disconnections", disconnections);
	return result;
}

void tf_ssb_record_thread_busy(tf_ssb_t* ssb, bool busy)
{
	int32_t busy_value = __atomic_add_fetch(&ssb->thread_busy_count, busy ? 1 : -1, __ATOMIC_RELAXED);
	int32_t current = ssb->thread_busy_max;
	while (busy_value > current && !__atomic_compare_exchange_n(&ssb->thread_busy_max, &current, busy_value, false, __ATOMIC_RELAXED, __ATOMIC_RELAXED))
	{
		current = ssb->thread_busy_max;
	}
}

float tf_ssb_get_average_thread_percent(tf_ssb_t* ssb)
{
	if (!ssb || !ssb->thread_busy_max)
	{
		return 0.0f;
	}

	return 100.0f * ssb->thread_busy_count / ssb->thread_busy_max;
}

void tf_ssb_set_hitch_callback(tf_ssb_t* ssb, void (*callback)(const char* name, uint64_t duration_ns, void* user_data), void* user_data)
{
	ssb->hitch_callback = callback;
	ssb->hitch_user_data = user_data;
}

tf_ssb_store_queue_t* tf_ssb_get_store_queue(tf_ssb_t* ssb)
{
	return &ssb->store_queue;
}

void tf_ssb_ref(tf_ssb_t* ssb)
{
	ssb->ref_count++;
}

void tf_ssb_unref(tf_ssb_t* ssb)
{
	int new_count = --ssb->ref_count;
	if (new_count < 0)
	{
		tf_printf("tf_ssb_unref past 0: %d\n", new_count);
		abort();
	}
}

void tf_ssb_set_main_thread(tf_ssb_t* ssb, bool main_thread)
{
	ssb->thread_self = main_thread ? uv_thread_self() : 0;
}

typedef struct _connection_work_t
{
	uv_work_t work;
	tf_ssb_connection_t* connection;
	const char* name;
	const char* after_name;
	void (*work_callback)(tf_ssb_connection_t* connection, void* user_data);
	void (*after_work_callback)(tf_ssb_connection_t* connection, int result, void* user_data);
	void* user_data;
} connection_work_t;

static void _tf_ssb_connection_work_callback(uv_work_t* work)
{
	connection_work_t* data = work->data;
	tf_ssb_record_thread_busy(data->connection->ssb, true);
	if (data->work_callback)
	{
		tf_trace_begin(data->connection->ssb->trace, data->name);
		data->work_callback(data->connection, data->user_data);
		tf_trace_end(data->connection->ssb->trace);
	}
	tf_ssb_record_thread_busy(data->connection->ssb, false);
}

static void _tf_ssb_connection_after_work_callback(uv_work_t* work, int status)
{
	connection_work_t* data = work->data;
	if (data->after_work_callback)
	{
		tf_trace_begin(data->connection->ssb->trace, data->after_name);
		data->after_work_callback(data->connection, status, data->user_data);
		tf_trace_end(data->connection->ssb->trace);
	}
	data->connection->ref_count--;
	if (data->connection->ref_count == 0 && data->connection->closing)
	{
		_tf_ssb_connection_destroy(data->connection, "work completed");
	}
	tf_free((void*)data->name);
	tf_free((void*)data->after_name);
	tf_free(data);
}

void tf_ssb_connection_run_work(tf_ssb_connection_t* connection, void (*work_callback)(tf_ssb_connection_t* connection, void* user_data),
	void (*after_work_callback)(tf_ssb_connection_t* connection, int result, void* user_data), void* user_data)
{
	connection_work_t* work = tf_malloc(sizeof(connection_work_t));
	*work = (connection_work_t)
	{
		.work =
		{
			.data = work,
		},
		.connection = connection,
		.work_callback = work_callback,
		.after_work_callback = after_work_callback,
		.user_data = user_data,
	};

	connection->ref_count++;
	int result = uv_queue_work(connection->ssb->loop, &work->work, _tf_ssb_connection_work_callback, _tf_ssb_connection_after_work_callback);
	if (result)
	{
		_tf_ssb_connection_after_work_callback(&work->work, result);
	}
}

typedef struct _ssb_work_t
{
	uv_work_t work;
	tf_ssb_t* ssb;
	const char* name;
	const char* after_name;
	void (*work_callback)(tf_ssb_t* ssb, void* user_data);
	void (*after_work_callback)(tf_ssb_t* ssb, int result, void* user_data);
	void* user_data;
} ssb_work_t;

static void _tf_ssb_work_callback(uv_work_t* work)
{
	ssb_work_t* data = work->data;
	tf_ssb_record_thread_busy(data->ssb, true);
	if (data->work_callback)
	{
		tf_trace_begin(data->ssb->trace, data->name);
		data->work_callback(data->ssb, data->user_data);
		tf_trace_end(data->ssb->trace);
	}
	tf_ssb_record_thread_busy(data->ssb, false);
}

static void _tf_ssb_after_work_callback(uv_work_t* work, int status)
{
	ssb_work_t* data = work->data;
	if (data->after_work_callback)
	{
		tf_trace_begin(data->ssb->trace, data->after_name);
		data->after_work_callback(data->ssb, status, data->user_data);
		tf_trace_end(data->ssb->trace);
	}
	tf_ssb_unref(data->ssb);
	tf_free((void*)data->name);
	tf_free((void*)data->after_name);
	tf_free(data);
}

void tf_ssb_run_work(tf_ssb_t* ssb, void (*work_callback)(tf_ssb_t* ssb, void* user_data), void (*after_work_callback)(tf_ssb_t* ssb, int result, void* user_data), void* user_data)
{
	ssb_work_t* work = tf_malloc(sizeof(ssb_work_t));
	*work = (ssb_work_t)
	{
		.work =
		{
			.data = work,
		},
		.name = tf_util_function_to_string(work_callback),
		.after_name = tf_util_function_to_string(after_work_callback),
		.ssb = ssb,
		.work_callback = work_callback,
		.after_work_callback = after_work_callback,
		.user_data = user_data,
	};

	tf_ssb_ref(ssb);
	int result = uv_queue_work(ssb->loop, &work->work, _tf_ssb_work_callback, _tf_ssb_after_work_callback);
	if (result)
	{
		_tf_ssb_connection_after_work_callback(&work->work, result);
	}
}

bool tf_ssb_is_room(tf_ssb_t* ssb)
{
	return ssb->is_room;
}

void tf_ssb_set_is_room(tf_ssb_t* ssb, bool is_room)
{
	ssb->is_room = is_room;
}

const char* tf_ssb_get_room_name(tf_ssb_t* ssb)
{
	return ssb->room_name;
}

void tf_ssb_set_room_name(tf_ssb_t* ssb, const char* room_name)
{
	tf_free(ssb->room_name);
	ssb->room_name = tf_strdup(room_name);
}

typedef struct _update_settings_t
{
	bool is_room;
	char seeds_host[256];
	char room_name[1024];
} update_settings_t;

static bool _get_global_setting_string(tf_ssb_t* ssb, const char* name, char* out_value, size_t size)
{
	bool result = false;
	sqlite3* db = tf_ssb_acquire_db_reader(ssb);
	sqlite3_stmt* statement;
	if (sqlite3_prepare(db, "SELECT json_extract(value, '$.' || ?) FROM properties WHERE id = 'core' AND key = 'settings'", -1, &statement, NULL) == SQLITE_OK)
	{
		if (sqlite3_bind_text(statement, 1, name, -1, NULL) == SQLITE_OK)
		{
			if (sqlite3_step(statement) == SQLITE_ROW)
			{
				snprintf(out_value, size, "%s", sqlite3_column_text(statement, 0));
				result = true;
			}
		}
		sqlite3_finalize(statement);
	}
	else
	{
		tf_printf("prepare failed: %s\n", sqlite3_errmsg(db));
	}
	tf_ssb_release_db_reader(ssb, db);
	return result;
}

static bool _get_global_setting_bool(tf_ssb_t* ssb, const char* name, bool default_value)
{
	bool result = default_value;
	sqlite3* db = tf_ssb_acquire_db_reader(ssb);
	sqlite3_stmt* statement;
	if (sqlite3_prepare(db, "SELECT json_extract(value, '$.' || ?) FROM properties WHERE id = 'core' AND key = 'settings'", -1, &statement, NULL) == SQLITE_OK)
	{
		if (sqlite3_bind_text(statement, 1, name, -1, NULL) == SQLITE_OK)
		{
			if (sqlite3_step(statement) == SQLITE_ROW)
			{
				result = sqlite3_column_int(statement, 0) != 0;
			}
		}
		sqlite3_finalize(statement);
	}
	else
	{
		tf_printf("prepare failed: %s\n", sqlite3_errmsg(db));
	}
	tf_ssb_release_db_reader(ssb, db);
	return result;
}

static void _tf_ssb_update_settings_work(tf_ssb_t* ssb, void* user_data)
{
	update_settings_t* update = user_data;
	update->is_room = _get_global_setting_bool(ssb, "room", true);
	_get_global_setting_string(ssb, "room_name", update->room_name, sizeof(update->room_name));
	_get_global_setting_string(ssb, "seeds_host", update->seeds_host, sizeof(update->seeds_host));
}

static void _tf_ssb_update_settings_after_work(tf_ssb_t* ssb, int result, void* user_data)
{
	update_settings_t* update = user_data;
	tf_ssb_set_is_room(ssb, update->is_room);
	tf_ssb_set_room_name(ssb, update->room_name);
	snprintf(ssb->seeds_host, sizeof(ssb->seeds_host), "%s", update->seeds_host);
	_tf_ssb_start_update_settings(ssb);
	tf_free(update);
}

static void _tf_ssb_start_update_settings_timer(tf_ssb_t* ssb, void* user_data)
{
	update_settings_t* update = tf_malloc(sizeof(update_settings_t));
	*update = (update_settings_t) { 0 };
	tf_ssb_run_work(ssb, _tf_ssb_update_settings_work, _tf_ssb_update_settings_after_work, update);
}

static void _tf_ssb_update_settings(tf_ssb_t* ssb)
{
	update_settings_t* update = tf_malloc(sizeof(update_settings_t));
	*update = (update_settings_t) { 0 };
	_tf_ssb_update_settings_work(ssb, update);
	_tf_ssb_update_settings_after_work(ssb, 0, update);
}

static void _tf_ssb_start_update_settings(tf_ssb_t* ssb)
{
	tf_ssb_schedule_work(ssb, 5000, _tf_ssb_start_update_settings_timer, NULL);
}

void tf_ssb_set_verbose(tf_ssb_t* ssb, bool verbose)
{
	ssb->verbose = verbose;
}

static void _tf_ssb_scheduled_timer(uv_timer_t* handle)
{
	tf_ssb_timer_t* timer = handle->data;
	timer->callback(timer->ssb, timer->user_data);
	for (int i = 0; i < timer->ssb->timers_count; i++)
	{
		if (timer->ssb->timers[i] == timer)
		{
			timer->ssb->timers[i] = timer->ssb->timers[--timer->ssb->timers_count];
			break;
		}
	}
	uv_close((uv_handle_t*)handle, _tf_ssb_on_timer_close);
}

void tf_ssb_schedule_work(tf_ssb_t* ssb, int delay_ms, void (*callback)(tf_ssb_t* ssb, void* user_data), void* user_data)
{
	ssb->timers = tf_resize_vec(ssb->timers, sizeof(uv_timer_t*) * (ssb->timers_count + 1));
	tf_ssb_timer_t* timer = tf_malloc(sizeof(tf_ssb_timer_t));
	*timer = (tf_ssb_timer_t)
	{
		.ssb = ssb,
		.timer =
		{
			.data = timer,
		},
		.callback = callback,
		.user_data = user_data,
	};
	ssb->timers[ssb->timers_count++] = timer;
	uv_timer_init(ssb->loop, &timer->timer);
	uv_timer_start(&timer->timer, _tf_ssb_scheduled_timer, delay_ms, 0);
	uv_unref((uv_handle_t*)&timer->timer);
}

bool tf_ssb_hmacsha256_verify(const char* public_key, const void* payload, size_t payload_length, const char* signature, bool signature_is_urlb64)
{
	bool result = false;

	const char* public_key_start = public_key && *public_key == '@' ? public_key + 1 : public_key;
	const char* public_key_end = public_key_start ? strstr(public_key_start, ".ed25519") : NULL;
	if (public_key_start && !public_key_end)
	{
		public_key_end = public_key_start + strlen(public_key_start);
	}

	uint8_t bin_public_key[crypto_sign_PUBLICKEYBYTES] = { 0 };
	if (tf_base64_decode(public_key_start, public_key_end - public_key_start, bin_public_key, sizeof(bin_public_key)) > 0)
	{
		uint8_t bin_signature[crypto_sign_BYTES] = { 0 };
		if (sodium_base642bin(bin_signature, sizeof(bin_signature), signature, strlen(signature), NULL, NULL, NULL,
				signature_is_urlb64 ? sodium_base64_VARIANT_URLSAFE_NO_PADDING : sodium_base64_VARIANT_ORIGINAL) == 0)
		{
			if (crypto_sign_verify_detached(bin_signature, (const uint8_t*)payload, payload_length, bin_public_key) == 0)
			{
				result = true;
			}
		}
	}
	return result;
}

JSValue tf_ssb_connection_requests_to_object(tf_ssb_connection_t* connection)
{
	JSContext* context = connection->ssb->context;
	JSValue object = JS_NewArray(context);
	for (int i = 0; i < connection->requests_count; i++)
	{
		JSValue request = JS_NewObject(context);
		JS_SetPropertyStr(context, request, "name", JS_NewString(context, connection->requests[i].name));
		JS_SetPropertyStr(context, request, "request_number", JS_NewInt32(context, connection->requests[i].request_number));
		JS_SetPropertyUint32(context, object, i, request);
	}
	return object;
}

void tf_ssb_connection_adjust_read_backpressure(tf_ssb_connection_t* connection, int delta)
{
	const int k_threshold = 256;
	int old_pressure = connection->read_back_pressure;
	connection->read_back_pressure += delta;
	if (!connection->closing)
	{
		if (old_pressure < k_threshold && connection->read_back_pressure >= k_threshold)
		{
			_tf_ssb_connection_read_stop(connection);
		}
		else if (old_pressure >= k_threshold && connection->read_back_pressure < k_threshold)
		{
			_tf_ssb_connection_read_start(connection);
		}
	}
	connection->ref_count += delta;
	if (connection->ref_count == 0 && connection->closing)
	{
		_tf_ssb_connection_destroy(connection, "backpressure released");
	}
}

void tf_ssb_connection_adjust_write_count(tf_ssb_connection_t* connection, int delta)
{
	connection->active_write_count += delta;
	_tf_ssb_connection_dispatch_scheduled(connection);
}