bip/src/connection.c

/*
 * $Id: connection.c,v 1.98 2005/04/12 19:34:35 nohar Exp $
 *
 * This file is part of the bip project
 * Copyright (C) 2004 Arnaud Cornet and Loïc Gomez
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 * See the file "COPYING" for the exact licensing terms.
 */

#include "config.h"
#include <sys/time.h>
#include <time.h>
#include "connection.h"

extern int errno;
#ifdef HAVE_LIBSSL
static SSL_CTX *sslctx = NULL;
static BIO *errbio = NULL;
extern char *conf_ssl_certfile;
static int SSLize(connection_t *cn);
static int SSL_init_context(void);
#endif

static int connection_timedout(connection_t *cn);
static int socket_set_nonblock(int s);

struct connecting_data
{
	struct addrinfo *dst;
	struct addrinfo *src;
	struct addrinfo *cur;
};

static void connecting_data_free(struct connecting_data *t)
{
	if (t->dst)
		freeaddrinfo(t->dst);
	if (t->src)
		freeaddrinfo(t->src);
	free(t);
}

void connection_close(connection_t *cn)
{
	mylog(LOG_DEBUG, "Connection close asked. FD:%d ", (long)cn->handle);
	cn->connected = CONN_DISCONN;
	shutdown(cn->handle, SHUT_RDWR);
	close(cn->handle);
}

void connection_free(connection_t *cn)
{
	connection_close(cn);

	if (cn->outgoing) {
		char *l;
		while ((l = list_remove_first(cn->outgoing)))
			free(l);
		list_free(cn->outgoing);
	}
	if (cn->incoming_lines)
		list_free(cn->incoming_lines);
	if (cn->incoming)
		free(cn->incoming);
	if (cn->ip_list)
		list_free(cn->ip_list);
	if (cn->connecting_data)
		connecting_data_free(cn->connecting_data);
	/* conn->user_data */
#ifdef HAVE_LIBSSL
	if (cn->ssl) {
		if (cn->cert) {
			X509_free(cn->cert);
			cn->cert = NULL;
		}
		if (cn->ssl_h) {
			SSL_shutdown(cn->ssl_h);
			SSL_free(cn->ssl_h);
			cn->ssl_h = NULL;
		}
	}
#endif
	free(cn);
}

/* XXX
 * m'expliquer le local bind
 * API Suxor
 */
static void connect_trynext(connection_t *cn)
{
	struct addrinfo *cur;
	int err;
	
	if (!cn->connecting_data)
		fatal("called connect_trynext with a connection not "
				"connecting\n");

	cur = cn->connecting_data->cur;

	for (cur = cn->connecting_data->cur ; cur ; cur = cur->ai_next) {
		if ((cn->handle = socket(cur->ai_family, cur->ai_socktype,
						cur->ai_protocol)) < 0) {
			mylog(LOG_WARN, "socket() : %s", strerror(errno));
			continue;
		}

		socket_set_nonblock(cn->handle);

		if (cn->connecting_data->src) {
			/* local bind */
			err = bind(cn->handle,
					cn->connecting_data->src->ai_addr,
					cn->connecting_data->src->ai_addrlen);
			if (err == -1)
				mylog(LOG_WARN, "bind() before connect: %s",
						strerror(errno));
		}

		err = connect(cn->handle, cur->ai_addr, cur->ai_addrlen);
		if (err == -1 && errno == EINPROGRESS) {
			/* ok for now, see later */
			/* next time try the next in the list */
			cn->connecting_data->cur = cur->ai_next;
			cn->connect_time = time(NULL);
			cn->connected = CONN_INPROGRESS;
			return;
		}

		if (!err) {
			/* connect() successful */
			connecting_data_free(cn->connecting_data);
			cn->connecting_data = NULL;
			cn->connected = cn->ssl ? CONN_NEED_SSLIZE : CONN_OK;
			return;
		}

		/* connect() failed */
		char ip[256];
		mylog(LOG_WARN, "connect(%s) : %s",
			inet_ntop(cur->ai_family, cur->ai_addr, ip, 256),
			strerror(errno));
		close(cn->handle);
		cn->handle = -1;
	}
	
	cn->connected = CONN_ERROR;
	connecting_data_free(cn->connecting_data);
	cn->connecting_data = NULL;
	mylog(LOG_ERROR, "connect() failed.");
}

#ifdef HAVE_LIBSSL
static X509 *mySSL_get_cert(SSL *ssl)
{
	X509 *cert;
	
	if (!ssl) {
		mylog(LOG_WARN, "mySSL_get_cert() No SSL context");
		return NULL;
	}
	cert = SSL_get_peer_certificate(ssl);
	if (cert == NULL)
		mylog(LOG_WARN, "mySSL_get_cert() SSL server supplied no "
				"certificate !");
	return cert;
}

static int _write_socket_SSL(connection_t *cn, char* message)
{
	int count, size;
	
	size = sizeof(char)*strlen(message);

	if (!cn->client && cn->cert == NULL) {
		cn->cert = mySSL_get_cert(cn->ssl_h);
		if (cn->cert == NULL) {
			mylog(LOG_ERROR, "No certificate in SSL write_socket");
			return WRITE_ERROR;
		}
	}
	count = SSL_write(cn->ssl_h, (const void *)message, size);
	ERR_print_errors(errbio);
	if (count <= 0) {
		int err = SSL_get_error(cn->ssl_h, count);
		if (err == SSL_ERROR_WANT_READ || err == SSL_ERROR_WANT_WRITE
				|| err == SSL_ERROR_WANT_CONNECT
				|| err == SSL_ERROR_WANT_ACCEPT)
			return WRITE_KEEP;
		if (cn_is_connected(cn)) {
			mylog(LOG_DEBUG, "fd %d: Connection error", cn->handle);
			cn->connected = CONN_ERROR;
		}
		return WRITE_ERROR;
	}
	if (count != size) {
		/* abnormal : openssl keeps writing until message is not fully
		 * sent */
		mylog(LOG_DEBUG, "only %d written while message length is %d",
				count,size);
	}

	mylog(LOG_DEBUGVERB, "%d/%d bytes sent", count, size);
	return WRITE_OK;
}
#endif

static int _write_socket(connection_t *cn, char* message)
{
	size_t size;
	size_t tcount = 0;
	ssize_t count;

	size = sizeof(char) * strlen(message);
	while ((count = write(cn->handle, ((const char*)message) + tcount,
					size - tcount)) > 0) {
		tcount += count;
		if (tcount == size)
			break;
	}
	if (count <= 0) {
		/*
		 * if no fatal error, return WRITE_KEEP, which makes caller
		 * keep line in its FIFO
		 */
		if (errno == EAGAIN || errno == EINTR || errno == EINPROGRESS)
			return WRITE_KEEP;

		if (cn_is_connected(cn)) {
			mylog(LOG_DEBUG, "write(fd %d) : %s", cn->handle,
					strerror(errno));
			cn->connected = CONN_ERROR;
		}
		mylog(LOG_DEBUG, "write : %s", strerror(errno));
		return WRITE_ERROR;
	}
	mylog(LOG_DEBUGVERB, "%d/%d bytes sent !", tcount, size);
	return WRITE_OK;
}

static int write_socket(connection_t *cn, char *line)
{
#ifdef HAVE_LIBSSL
	if (cn->ssl)
		return _write_socket_SSL(cn, line);
	else
#endif
		return _write_socket(cn, line);

}

/* returns 1 if connection must be notified */
static int real_write_all(connection_t *cn)
{
	int ret;
	char *line;

	if (cn == NULL)
		fatal("real_write_all: wrong arguments");
	
	while ((line = list_remove_first(cn->outgoing))) {
		ret = write_socket(cn, line);

		switch (ret) {
		case WRITE_ERROR:
			return 1;
		case WRITE_KEEP:
			/* interrupted or not ready */
			list_add_first(cn->outgoing, line);
			return 0;
		case WRITE_OK:
			free(line);
			break;
		default:
			fatal("internal error 6");
			break;
		}

		if (cn->anti_flood)
			/* one line at a time */
			break;
	}
	return 0;	
}

void write_line_fast(connection_t *cn, char *line)
{
	int r;
	r = write_socket(cn, line);
	switch (r) {
	case WRITE_KEEP:
		list_add_first(cn->outgoing, strdup(line));
		break;
	case WRITE_ERROR:
		cn->connected = CONN_ERROR;
		break;
	case WRITE_OK:
		break;
	default:
		fatal("internal error 7");
		break;
	}
}

void write_line(connection_t *cn, char *line)
{
	list_add_last(cn->outgoing, strdup(line));
}

list_t *read_lines(connection_t *cn, int *error)
{
	list_t *ret = NULL;

	switch (cn->connected) {
	case CONN_TIMEOUT:
	case CONN_ERROR:
	case CONN_DISCONN:
	case CONN_EXCEPT:
		*error = 1;
		ret = NULL;
		break;
	case CONN_NEW:
	case CONN_INPROGRESS:
	case CONN_NEED_SSLIZE:
		*error = 0;
		ret = NULL;
		break;
	case CONN_OK:
		*error = 0;
		ret = cn->incoming_lines;
		cn->incoming_lines = NULL;
		break;
	default:
		fatal("internal error 8");
		break;
	}
	return ret;
}

#ifdef HAVE_LIBSSL
/* returns 1 if connection must be notified */
static int read_socket_SSL(connection_t *cn)
{
	int max, count;

	max = CONN_BUFFER_SIZE - cn->incoming_end;
	if (!cn->client && cn->cert == NULL) {
		cn->cert = mySSL_get_cert(cn->ssl_h);
		if (cn->cert == NULL) {
			mylog(LOG_ERROR, "No certificate in SSL read_socket");
			return -1;
		}
	}
	count = SSL_read(cn->ssl_h, (void *)cn->incoming + cn->incoming_end,
			sizeof(char) * max);
	ERR_print_errors(errbio);
	if (count < 0) {
		int err = SSL_get_error(cn->ssl_h, count);
		if (err == SSL_ERROR_WANT_READ || err == SSL_ERROR_WANT_WRITE
				|| err == SSL_ERROR_WANT_CONNECT
				|| err == SSL_ERROR_WANT_ACCEPT)
			return 0;
		if (cn_is_connected(cn)) {
			mylog(LOG_DEBUG, "fd %d: Connection error",cn->handle);
			cn->connected = CONN_ERROR;
		}
		return 1;
	} else if (count == 0) {
/*		int err = SSL_get_error(cn->ssl_h,count);
		if (err == SSL_ERROR_WANT_READ || err == SSL_ERROR_WANT_WRITE
				|| err == SSL_ERROR_WANT_CONNECT
				|| err == SSL_ERROR_WANT_ACCEPT)
			return 0;*/
		if (cn_is_connected(cn)) {
			mylog(LOG_DEBUG, "fd %d: Connection lost",cn->handle);
			cn->connected = CONN_DISCONN;
		}
		return 1;
	}

	cn->incoming_end += count;
	return 0;
}
#endif

/* returns 1 if connection must be notified */
static int read_socket(connection_t *cn)
{
	int max, count;
	
	if (cn == NULL)
		return 0;
	max = CONN_BUFFER_SIZE - cn->incoming_end;
	count = read(cn->handle, cn->incoming+cn->incoming_end,
			sizeof(char)*max);
	if (count < 0) {
		if (errno == EAGAIN || errno == EINTR || errno == EINPROGRESS)
			return 0;
		if (cn_is_connected(cn)) {
			mylog(LOG_DEBUG, "fd %d: Connection error",cn->handle);
			mylog(LOG_DEBUG, "fd %d: read() %s", cn->handle,
					strerror(errno));
			cn->connected = CONN_ERROR;
		}
		return 1;
	} else if (count == 0) {
		if (cn_is_connected(cn)) {
			mylog(LOG_DEBUG, "fd %d: Connection lost", cn->handle);
			cn->connected = CONN_DISCONN;
			mylog(LOG_DEBUG, "fd %d: read() %s", cn->handle,
					strerror(errno));
		}
		return 1;
	}

	cn->incoming_end += count;
	return 0;
}

static void data_find_lines(connection_t *cn)
{
	size_t len = 0, lastlen = 0, ssz;
	char *p = cn->incoming;
	char *buf;

	for (;;) {
		while (len < cn->incoming_end && p[len] != '\n')
			len++;
		if (len >= cn->incoming_end || p[len] != '\n')
			break;

		ssz = len - lastlen;
		if (ssz >= 1) {
			if (p[len - 1] == '\r')
				ssz--;
			buf = malloc(ssz + 1);
			memcpy(buf, p + lastlen, ssz);
			buf[ssz] = 0;

			list_add_last(cn->incoming_lines, buf);
		}

		len++;
		lastlen = len;
	}
	if (lastlen) {
		unsigned i;
		for (i = 0; i < cn->incoming_end - lastlen; i++)
			p[i] = p[i + lastlen];
		cn->incoming_end -= lastlen;
	}
}

int cn_is_new(connection_t *cn)
{
	switch (cn->connected) {
	case CONN_TIMEOUT:
	case CONN_ERROR:
	case CONN_DISCONN:
	case CONN_EXCEPT:
	case CONN_NEED_SSLIZE:
	case CONN_OK:
		return 0;
	case CONN_NEW:
	case CONN_INPROGRESS:
		return 1;
	default:
		fatal("internal error 9");
		return 0;
	}
}

int cn_is_in_error(connection_t *cn)
{
	switch (cn->connected) {
	case CONN_TIMEOUT:
	case CONN_ERROR:
	case CONN_DISCONN:
	case CONN_EXCEPT:
		return 1;
	case CONN_NEW:
	case CONN_INPROGRESS:
	case CONN_NEED_SSLIZE:
	case CONN_OK:
		return 0;
	default:
		fatal("internal error 10");
		return 1;
	}
}

int cn_is_connected(connection_t *cn) 
{
	if (cn == NULL)
		fatal("cn_is_connected, wrong argument");
	return (cn->connected == CONN_OK ? 1 : 0);
}

static int check_event_except(fd_set *fds, connection_t *cn)
{
	if (!cn_is_connected(cn))
		return 0;

	if (cn_is_in_error(cn)) {
		mylog(LOG_DEBUGVERB, "Error on fd %d (state %d)",
				cn->handle, cn->connected);
		return 1;
	}
	
	if (!FD_ISSET(cn->handle, fds))
		return 0;
	
	mylog(LOG_DEBUG,"fd %d is in exceptions list", cn->handle);
	cn->connected = CONN_EXCEPT;
	return 1;
}

static int check_event_read(fd_set *fds, connection_t *cn)
{
	int ret;

	if (cn_is_in_error(cn)) {
		mylog(LOG_DEBUGVERB, "Error on fd %d (state %d)",
				cn->handle, cn->connected);
		return 1;
	}

	if (!FD_ISSET(cn->handle, fds))
		return 0;

	mylog(LOG_DEBUGVERB, "Read positif sur fd %d (state %d)", cn->handle,
			cn->connected);

	/* notify caller to make it check for a new client */
	if (cn->listening)
		return 1;

#ifdef HAVE_LIBSSL
	if (cn->ssl)
		ret = read_socket_SSL(cn);
	else
#endif
		ret = read_socket(cn);
	
	if (ret) {
		mylog(LOG_DEBUGVERB, "Error while reading on fd %d",
				cn->handle);
 		return 1;
 	}
	
	if (!cn->incoming_lines)
		cn->incoming_lines = list_new(NULL);
	data_find_lines(cn);
	if (list_is_empty(cn->incoming_lines))
		return 0;
	
	mylog(LOG_DEBUGVERB, "newlines sur fd %d (state %d)", cn->handle,
			cn->connected);
	return 1;
}

static int check_event_write(fd_set *fds, connection_t *cn)
{
	if (cn_is_in_error(cn)) {
		mylog(LOG_DEBUGVERB, "Error on fd %d (state %d)",
				cn->handle, cn->connected);
		return 1;
	}

	if (!FD_ISSET(cn->handle, fds)) {
		if (cn_is_connected(cn))
			return 0;
		
		mylog(LOG_DEBUGVERB, "New socket still not connected (%d)",
				cn->handle);
		/* check timeout (handles connect_trynext) */
		return connection_timedout(cn);
	}

	mylog(LOG_DEBUGVERB, "Write positif sur fd %d (state %d)",
			cn->handle, cn->connected);
	
	if (cn_is_new(cn)) {
		int err, err2;
		socklen_t errSize = sizeof(err);

		err2 = getsockopt(cn->handle,SOL_SOCKET,SO_ERROR,(void *)&err,
				&errSize);
		
		if (err2 < 0) {
			mylog(LOG_WARN, "fd:%d getsockopt error: %s",
					cn->handle, strerror(errno));
			connect_trynext(cn);
			return (cn_is_new(cn) || cn->connected ==
					CONN_NEED_SSLIZE) ? 0 : 1;
			
		} else if (err == EINPROGRESS || err == EALREADY) {
			mylog(LOG_INFO, "fd:%d Connection in progress...",
					cn->handle);
			return connection_timedout(cn);
		} else if (err == EISCONN || err == 0) {
#ifdef HAVE_LIBSSL
			if (cn->ssl) {
				cn->connected = CONN_NEED_SSLIZE;
				return 0;
			}
#endif
			cn->connected = CONN_OK;
			mylog(LOG_INFO, "fd:%d Connection established !",
					cn->handle);
			return 1;
		} else {
			mylog(LOG_WARN, "fd:%d Socket error: %s", cn->handle,
					strerror(err));
			connect_trynext(cn);
			return (cn_is_new(cn) || cn->connected ==
					CONN_NEED_SSLIZE) ? 0 : 1;
		}
	}

#ifdef HAVE_LIBSSL
	if (cn->connected == CONN_NEED_SSLIZE) {
		if (SSLize(cn))
			return connection_timedout(cn);
		return 0;
	}
#endif

	if (cn_is_connected(cn) && !list_is_empty(cn->outgoing))
		real_write_all(cn);

	return 0;
}

static void connection_ready_output(connection_t *c)
{
}

/* starts empty */
/* capacity: 4 token */
#define TOKEN_MAX 4
/* token generation interval: 1200ms */
#define TOKEN_INTERVAL 1200

int cn_want_write(connection_t *cn)
{
	if (cn->anti_flood) {
		struct timeval tv;
		unsigned long now;

		/* fill the bucket */
		/* we do not control when we are called */
		/* now is the number of milliseconds since the Epoch,
		 * cn->lasttoken is the number of milliseconds when we
		 * last added a token to the bucket */
		if (!gettimeofday(&tv, NULL)) {
			now = tv.tv_sec * 1000 + tv.tv_usec / 1000;
			/* round now to TOKEN_INTERVAL multiple */
			now -= now % TOKEN_INTERVAL;
			if (now < cn->lasttoken) {
				/* time shift or integer overflow */
				cn->token = 1;
				cn->lasttoken = now;
			} else if (now > cn->lasttoken + TOKEN_INTERVAL) {
				/* there may be an overflow here
				 * but the impact is insignificant */
				cn->token += (now - cn->lasttoken) /
					TOKEN_INTERVAL;
				if (cn->token > TOKEN_MAX)
					cn->token = TOKEN_MAX;
				cn->lasttoken = now;
			}
		} else
			/* if gettimeofday() fails, juste ignore
			 * antiflood */
			cn->token = 1;

		/* use a token if needed and available */
		if (!list_is_empty(cn->outgoing) && cn->token > 0) {
			cn->token--;
			return 1;
		}
		return 0;
	}
	return !list_is_empty(cn->outgoing);
}

list_t *wait_event(list_t *cn_list, int *msec)
{
	fd_set fds_read, fds_write, fds_except;
	int maxfd = -1, err;
	list_t *cn_newdata;
	list_iterator_t it;
	struct timeval tv;
	struct timeval btv, etv;

	cn_newdata = list_new(NULL);
	FD_ZERO(&fds_read);
	FD_ZERO(&fds_write);
	FD_ZERO(&fds_except);
	for (list_it_init(cn_list, &it); list_it_item(&it); list_it_next(&it)) {
		connection_t *cn = list_it_item(&it);
		if (cn == NULL)
			fatal("wait_event: wrong argument");

		mylog(LOG_DEBUGTOOMUCH, "I've seen socket %d !", cn->handle);
		if (cn->connected == CONN_DISCONN) {
			list_add_first(cn_newdata, cn);
			continue;
		}

		/*
		 * This shouldn't happen ! just in case...
		 */
		if (cn->handle < 0) {
			mylog(LOG_DEBUG, "wait_event invalid socket %d",
					cn->handle);
			if (cn_is_connected(cn))
				cn->connected = CONN_ERROR;
			continue;
		}

		/* exceptions are OOB and disconnections */
		FD_SET(cn->handle, &fds_except);
		maxfd = (cn->handle > maxfd ? cn->handle : maxfd);

		/*
		 * if connected, we're looking for new incoming data
		 * if new or lines waiting to be sent, we want
		 * to know if it's ready or not.
		 */
		if (cn_is_connected(cn)) {
			FD_SET(cn->handle, &fds_read);
			mylog(LOG_DEBUGVERB, "Test read sur fd %d %d:%d",
					cn->handle, cn->connected,
					cn_is_connected(cn));
		}
		
		/* we NEVER want to check write on a listening socket */
		if (cn->listening)
			continue;
		
		if (!cn_is_connected(cn) || cn_want_write(cn)) {
			FD_SET(cn->handle, &fds_write);
			mylog(LOG_DEBUGVERB, "Test write sur fd %d %d:%d",
					cn->handle, cn->connected,
					cn_is_connected(cn));
		}
	}
	
	/* if no connection is active, return the list... empty... */
	if (maxfd == -1)
		return cn_newdata;

	tv.tv_sec = *msec / 1000;
	tv.tv_usec = (*msec % 1000) * 1000;
	gettimeofday(&btv, NULL);
	mylog(LOG_DEBUGVERB,"msec: %d, sec: %d, usec: %d", *msec, tv.tv_sec,
			tv.tv_usec);
	err = select(maxfd + 1, &fds_read, &fds_write, &fds_except, &tv);
	gettimeofday(&etv, NULL);
	
	if (etv.tv_sec < btv.tv_sec)
		mylog(LOG_ERROR, "Time rewinded ! not touching interval");
	else
		*msec -= (etv.tv_sec - btv.tv_sec) * 1000
			+ (etv.tv_usec - btv.tv_usec) / 1000;
	/* in case we go forward in time */
	if (*msec < 0)
		*msec = 0;
	mylog(LOG_DEBUGVERB,"msec: %d, sec: %d, usec: %d", *msec, tv.tv_sec,
			tv.tv_usec);
	if (err < 0) {
		if (errno == EINTR)
			return cn_newdata;
		fatal("select(): %s", strerror(errno));
	} else if (err == 0) {
		mylog(LOG_DEBUGTOOMUCH, "Select timed-out. irc.o timer !");
		/* select timed-out */
		return cn_newdata;
	}

	for (list_it_init(cn_list, &it); list_it_item(&it); list_it_next(&it)) {
		connection_t *cn = list_it_item(&it);

		if (check_event_except(&fds_except, cn)) {
			mylog(LOG_DEBUGVERB,"Notify on FD %d (state %d)",
					cn->handle, cn->connected);
			list_add_first(cn_newdata, cn);
			continue;
 		}
		if (check_event_write(&fds_write, cn))
			connection_ready_output(cn);

		if (check_event_read(&fds_read, cn)) {
			mylog(LOG_DEBUGVERB, "Notify on FD %d (state %d)",
					cn->handle, cn->connected);
			list_add_first(cn_newdata, cn);
		}
	}
	return cn_newdata;
}

static void create_socket(char *dsthostname, char *dstport, char *srchostname,
		char *srcport, connection_t *cn)
{
	int err;
	struct connecting_data *cdata;
	struct addrinfo hint;
	
	memset(&hint, 0, sizeof(hint));
	hint.ai_flags = AI_PASSIVE;
	hint.ai_family = PF_UNSPEC;
	hint.ai_socktype = SOCK_STREAM;
	hint.ai_protocol = 0;
	
	cn->connected = CONN_ERROR;
	cdata = (struct connecting_data *)
		malloc(sizeof(struct connecting_data));
	if (!cdata) {
		mylog(LOG_ERROR, "malloc() : %s", strerror(errno));
		return;
	}
	cdata->dst = cdata->src = cdata->cur = NULL;

	err = getaddrinfo(dsthostname, dstport, &hint, &cdata->dst);
	if (err) {
		mylog(LOG_ERROR, "getaddrinfo(dst): %s", gai_strerror(err));
		connecting_data_free(cdata);
		cdata = NULL;
		return;
 	}

	if (srchostname || srcport) {
		if ((err = getaddrinfo(srchostname, srcport, &hint,
						&cdata->src))) {
			/* not fatal ? maybe a config option is needed */
			mylog(LOG_WARN, "getaddrinfo(src): %s",
					gai_strerror(err));
			cdata->src = NULL;
		}
	}
					
	cdata->cur = cdata->dst;
	cn->connecting_data = cdata;

	connect_trynext(cn);
}


static void create_listening_socket(char *hostname, char *port,
		connection_t *cn)
{
	int multi_client = 1;
	int err;
	struct addrinfo *res, *cur;
	struct addrinfo hint = {
		.ai_flags = AI_PASSIVE,
		.ai_family = PF_UNSPEC,
		.ai_socktype = SOCK_STREAM,
		.ai_protocol = 0,

		.ai_addrlen = 0,
		.ai_addr = 0,
		.ai_canonname = 0,
		.ai_next = 0
	};
 
	cn->connected = CONN_ERROR;
	
	err = getaddrinfo(hostname, port, &hint, &res);
	if (err) {
		mylog(LOG_ERROR, "getaddrinfo(): %s", gai_strerror(err));
		return;
 	}
	
	for (cur = res ; cur ; cur = cur->ai_next) {
		if ((cn->handle = socket(cur->ai_family, cur->ai_socktype,
						cur->ai_protocol)) < 0) {
			mylog(LOG_WARN, "socket : %s", strerror(errno));
			continue;
		}
		
		if (setsockopt(cn->handle, SOL_SOCKET, SO_REUSEADDR,
					(char *)&multi_client,
					sizeof(multi_client)) < 0) {
			mylog(LOG_WARN, "setsockopt() : %s", strerror(errno));
			close(cn->handle);
			cn->handle = -1;
			continue;
		}
		
		socket_set_nonblock(cn->handle);
		
		if (bind(cn->handle, cur->ai_addr, cur->ai_addrlen) < 0) {
			mylog(LOG_WARN, "bind() : %s", strerror(errno));
			close(cn->handle);
			cn->handle = -1;
			continue;
		}

		err = listen(cn->handle, 1024);
		if (err == -1) {
			mylog(LOG_WARN, "listen() : %s", strerror(errno));
			close(cn->handle);
			cn->handle = -1;
			continue;
		}
		
		freeaddrinfo(res);
		cn->connected = CONN_OK;
		return;
	}
	freeaddrinfo(res);
	mylog(LOG_ERROR, "Unable to bind/listen");
	cn->connected = CONN_ERROR;
}

static connection_t *connection_init(int anti_flood, int ssl, int timeout,
		int listen)
{
	connection_t *conn;
	char *incoming;
	list_t *outgoing, *incoming_lines;

	conn = (connection_t*)malloc(sizeof(connection_t));
	incoming = (char*)malloc(sizeof(char) * CONN_BUFFER_SIZE);
	outgoing = list_new(NULL);
	incoming_lines = list_new(NULL);

	conn->anti_flood = anti_flood;
	conn->ssl = ssl;
	conn->lasttoken = 0;
	conn->token = TOKEN_MAX;
	conn->timeout = (listen ? 0 : timeout);
	conn->connect_time = 0;
	conn->incoming = incoming;
	conn->incoming_end = 0;
	conn->outgoing = outgoing;
	conn->incoming_lines = NULL;
	conn->user_data = NULL;
	conn->listening = listen;
	conn->handle = -1;
	conn->client = 0;
	conn->ip_list = NULL;
	conn->connecting_data = NULL;
#ifdef HAVE_LIBSSL
	conn->ssl_h = NULL;
	conn->cert = NULL;
#endif
	conn->connected = CONN_NEW;
	
	return conn;
}

connection_t *accept_new(connection_t *cn)
{
	connection_t *conn;
	int err;
	socklen_t sa_len = sizeof (struct sockaddr);
	struct sockaddr sa;

	mylog(LOG_DEBUG, "Trying to accept new client on %d", cn->handle);
	err = accept(cn->handle, &sa, &sa_len);
	if (err < 0)
		return NULL;
	socket_set_nonblock(err);
	
	conn = connection_init(cn->anti_flood, cn->ssl, cn->timeout, 0);
	conn->connect_time = time(NULL);
	conn->user_data = cn->user_data;
	conn->handle = err;
	conn->client = 1;
#ifdef HAVE_LIBSSL
	if (cn->ssl) {
		if (!sslctx) {
			mylog(LOG_DEBUG, "No SSL context availaible. "
					"Initializing...");
			if (SSL_init_context()) {
				mylog(LOG_DEBUG, "SSL context initialization "
						"failed");
				connection_free(conn);
				return NULL;
			}
		}

		conn->ssl_h = SSL_new(sslctx);
		if (!conn->ssl_h) {
			connection_free(conn);
			return NULL;
		}
		SSL_set_accept_state(conn->ssl_h);
	}
#endif
	mylog(LOG_DEBUG, "New client on socket %d !",conn->handle);

	return conn;
}

connection_t *listen_new(char *hostname, int port, int ssl)
{
	connection_t *conn;
	char portbuf[20];
	/* TODO: allow litteral service name in the function interface */
	if (snprintf(portbuf, 20, "%d", port) >= 20)
		portbuf[19] = '\0';
	
	/*
	 * SSL flag is only here to tell program to convert socket to SSL after
	 * accept(). Listening socket will NOT be SSL
	 */
	conn = connection_init(0, ssl, 0, 1);
	create_listening_socket(hostname, portbuf, conn);

	return conn;
}

static connection_t *_connection_new(char *dsthostname, char *dstport,
		char *srchostname, char *srcport, int timeout)
{
	connection_t *conn;
	
	printf("%s\n", dsthostname);

	conn = connection_init(1, 0, timeout, 0);
	create_socket(dsthostname, dstport, srchostname, srcport, conn);
		
	return conn;
}

#ifdef HAVE_LIBSSL
static int SSL_init_context(void)
{
	int fd, flags, ret, rng;
	char buf[1025];
	
	if (sslctx) {
		mylog(LOG_DEBUG, "SSL already initialized");
		return 0;
	}

	SSL_library_init();
	SSL_load_error_strings();
	errbio = BIO_new_fp(stderr,BIO_NOCLOSE);
	
	/* allocated by function */
	sslctx = SSL_CTX_new(SSLv23_method());
	if (!sslctx)
		return 1;
	if (!SSL_CTX_use_certificate_chain_file(sslctx,conf_ssl_certfile)) {
		mylog(LOG_DEBUG, "SSL: Unable to load certificate file");
	}
	if (!SSL_CTX_use_PrivateKey_file(sslctx, conf_ssl_certfile,
				SSL_FILETYPE_PEM)) {
		mylog(LOG_DEBUG, "SSL: Unable to load key file");
	}
	SSL_CTX_set_session_cache_mode(sslctx, SSL_SESS_CACHE_BOTH);
	SSL_CTX_set_timeout(sslctx,(long)60);
	SSL_CTX_set_options(sslctx, SSL_OP_ALL);
	flags = O_RDONLY;
	flags |= O_NONBLOCK;
	fd = open("/dev/random", flags);
	if (fd < 0) {
		mylog(LOG_DEBUG, "SSL: /dev/random not ready, unable to "
				"manually seed PRNG.");
		goto prng_end;
	}

	do {
		ret = read(fd, buf, 1024);
		if (ret <= 0) {
			mylog(LOG_DEBUG,"/dev/random: %s",strerror(errno));
			goto prng_end;
		}
		mylog(LOG_DEBUG, "PRNG seeded with %d /dev/random bytes",
				ret);
		RAND_seed(buf, ret);
	} while (!(rng = RAND_status()));

prng_end:
	do {
		ret = close(fd);
	} while (ret != 0 && errno == EINTR);
	if (RAND_status()) {
		mylog(LOG_DEBUG, "SSL: PRNG is seeded !");
	} else {
		mylog(LOG_WARN, "SSL: PRNG is not seeded enough");
		mylog(LOG_WARN, "     OpenSSL will use /dev/urandom if "
				 "available.");
	}
	return 0;
}

static int SSLize(connection_t *cn)
{
	int err, err2;
	
	if (cn == NULL)
		return 1;

	if (cn->listening) {
		mylog(LOG_DEBUG, "Can't use SSL with listening socket.");
		return 0;
	}

	if (!SSL_set_fd(cn->ssl_h,cn->handle)) {
		mylog(LOG_DEBUG, "unable to associate FD to SSL structure");
		return 1;
	}
	
	if (cn->client)
		err = SSL_accept(cn->ssl_h);
	else
		err = SSL_connect(cn->ssl_h);

	err2 = SSL_get_error(cn->ssl_h, err);
	ERR_print_errors(errbio);
	
	if (err2 == SSL_ERROR_NONE) {
		SSL_CIPHER *cipher;
		char buf[128];
		int len;

		cipher = SSL_get_current_cipher(cn->ssl_h);
		SSL_CIPHER_description(cipher, buf, 128);
		len = strlen(buf);
		if (len > 0)
			buf[len-1] = '\0';
		mylog(LOG_DEBUG, "Negociated cyphers: %s",buf);
/*		if (SSL_get_verify_result(cn->ssl_h) != X509_V_OK) {
			mylog(LOG_ERROR, "Invalid certificate !");
			cn->connected = CONN_ERROR;
			return 1;
		}*/
		cn->connected = CONN_OK;
		return 0;
	}
	if (err2 == SSL_ERROR_ZERO_RETURN || err2 == SSL_ERROR_SSL) {
		mylog(LOG_DEBUG, "Error in SSL handshake.");
		cn->connected = CONN_ERROR;
		return 1;
	}
	return 0;
}

static connection_t *_connection_new_SSL(char *dsthostname, char *dstport,
		char *srchostname, char *srcport, int timeout)
{
	connection_t *conn;

	conn = connection_init(1, 1, timeout, 0);
	if (!sslctx) {
		mylog(LOG_DEBUG, "No SSL context availaible. Initializing...");
		if (SSL_init_context()) {
			mylog(LOG_DEBUG, "SSL context initialization failed");
			return conn;
		}
	}
	conn->cert = NULL;
	conn->ssl_h = SSL_new(sslctx);
	if (conn->ssl_h == NULL) {
		mylog(LOG_DEBUG, "Unable to allocate SSL structures");
		return conn;
	}

	if (sslctx->session_cache_head)
		if (!SSL_set_session(conn->ssl_h, sslctx->session_cache_head))
			mylog(LOG_DEBUG, "unable to set SSL session id to"
					" most recent used");
	SSL_set_connect_state(conn->ssl_h);

	create_socket(dsthostname, dstport, srchostname, srcport, conn);

	return conn;
}
#endif

connection_t *connection_new(char *dsthostname, int dstport, char *srchostname,
		int srcport, int ssl, int timeout)
{
	char dstportbuf[20], srcportbuf[20], *tmp;
	/* TODO: allow litteral service name in the function interface */
	if (snprintf(dstportbuf, 20, "%d", dstport) >= 20)
		dstportbuf[19] = '\0';
	if (srcport) {
		if (snprintf(srcportbuf, 20, "%d", srcport) >= 20)
			srcportbuf[19] = '\0';
		tmp = srcportbuf;
	} else
		tmp = NULL;
	
#ifdef HAVE_LIBSSL
	if (ssl)
		return _connection_new_SSL(dsthostname, dstportbuf, srchostname,
				tmp, timeout);
	else
#endif
		return _connection_new(dsthostname, dstportbuf, srchostname,
				tmp, timeout);
}

int cn_is_listening(connection_t *cn) 
{
	if (cn == NULL)
		return 0;
	else
		return cn->listening;
}

/* returns 1 if connection must be notified */
static int connection_timedout(connection_t *cn)
{
	if (cn_is_connected(cn) || !cn->timeout)
		return 0;

	if (!cn->connecting_data)
		fatal("connection_timedout called with no connecting_data!\n");
	
	if (time(NULL)-cn->connect_time > cn->timeout) {
		/* connect() completion timed out */
		connect_trynext(cn);
		if (!cn_is_new(cn) && cn->connected != CONN_NEED_SSLIZE)
			return 1;
	}
	return 0;
}

static int socket_set_nonblock(int s)
{
	if (fcntl(s, F_SETFL, O_NONBLOCK) < 0) {
		mylog(LOG_ERROR, "Cannot set socket %d to non blocking : %s",
				s, strerror(errno));
		return 0;
	}
	return 1;
}

#ifdef TEST
int main(int argc,char* argv[])
{
	connection_t *conn, *conn2;
	int s, cont = 1;

	if (argc != 3) {
		fprintf(stderr,"Usage: %s host port\n",argv[0]);
		exit(1);
	}
	conn = connection_init(0, 0, 0, 1);
	conn->connect_time = time(NULL);
	create_listening_socket(argv[1],argv[2],&conn);
	if (s == -1) {
		mylog(LOG_ERROR, "socket() : %s", strerror(errno));
		exit(1);
	}
	mylog(LOG_DEBUG, "Socket number %d",s);

	while (cont) {
		conn2 = accept_new(conn);
		if (conn2) {
			mylog(LOG_INFO, "New client");
			cont = 0;
		}
		sleep(1);
	}
	while (1) {
		int ret = read_socket(conn2);
		mylog(LOG_DEBUG, "READ: %d %*s",ret, conn2->incoming,
				conn2->incoming_end);
		conn2->incoming_end = 0;
		sleep(1);
	}
	return 0;
}
#endif