// Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced
// vim: sw=8 ts=8
-char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.114 2005/07/04 05:49:46 bodea Exp $";
+char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.115 2005/07/31 10:04:10 bodea Exp $";
#include <arpa/inet.h>
#include <assert.h>
#include <unistd.h>
#include <sched.h>
#include <sys/sysinfo.h>
+#include <openssl/md5.h>
#include <libcli.h>
-#include "md5.h"
#include "l2tpns.h"
#include "cluster.h"
#include "plugin.h"
CONFIG("pid_file", pid_file, STRING),
CONFIG("random_device", random_device, STRING),
CONFIG("l2tp_secret", l2tpsecret, STRING),
+ CONFIG("ppp_restart_time", ppp_restart_time, INT),
+ CONFIG("ppp_max_configure", ppp_max_configure, INT),
+ CONFIG("ppp_max_failure", ppp_max_failure, INT),
CONFIG("primary_dns", default_dns1, IPv4),
CONFIG("secondary_dns", default_dns2, IPv4),
CONFIG("primary_radius", radiusserver[0], IPv4),
static void sigalrm_handler(int sig);
static void shutdown_handler(int sig);
static void sigchild_handler(int sig);
-static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response);
+static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response);
static void update_config(void);
static void read_config_file(void);
static void initplugins(void);
va_end(ap);
}
-void _log_hex(int level, const char *title, const char *data, int maxsize)
+void _log_hex(int level, const char *title, const uint8_t *data, int maxsize)
{
int i, j;
- const uint8_t *d = (const uint8_t *) data;
+ const uint8_t *d = data;
if (config->debug < level) return;
tunidx = ifr.ifr_ifindex;
// Only setup IPv6 on the tun device if we have a configured prefix
- if (config->ipv6_prefix.s6_addr[0] > 0) {
+ if (config->ipv6_prefix.s6_addr[0]) {
ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
// Link local address is FE80::1
CSTAT(sessionbyipv6);
if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
- (ip.s6_addr[0] == 0xFE && ip.s6_addr[1] == 0x80 &&
- (ip.s6_addr16[1] == ip.s6_addr16[2] == ip.s6_addr16[3] == 0))) {
+ (ip.s6_addr[0] == 0xFE &&
+ ip.s6_addr[1] == 0x80 &&
+ ip.s6_addr16[1] == 0 &&
+ ip.s6_addr16[2] == 0 &&
+ ip.s6_addr16[3] == 0)) {
s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
} else {
s = lookup_ipv6map(ip);
// process outgoing (to tunnel) IP
//
-static void processipout(uint8_t * buf, int len)
+static void processipout(uint8_t *buf, int len)
{
sessionidt s;
sessiont *sp;
tunnelidt t;
in_addr_t ip;
- char *data = buf; // Keep a copy of the originals.
+ uint8_t *data = buf; // Keep a copy of the originals.
int size = len;
uint8_t b[MAXETHER + 20];
in_addr_t ip;
struct in6_addr ip6;
- char *data = buf; // Keep a copy of the originals.
+ uint8_t *data = buf; // Keep a copy of the originals.
int size = len;
uint8_t b[MAXETHER + 20];
}
// add a binary AVP
-static void controlb(controlt * c, uint16_t avp, char *val, unsigned int len, uint8_t m)
+static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
{
uint16_t l = ((m ? 0x8000 : 0) + len + 6);
*(uint16_t *) (c->buf + c->length + 0) = htons(l);
if (session[s].ip && !walled_garden && !session[s].die)
{
// RADIUS Stop message
- uint16_t r = sess_local[s].radius;
- if (!r)
- r = radiusnew(s);
-
+ uint16_t r = radiusnew(s);
if (r)
{
// stop, if not already trying
free_ip_address(s);
// unroute IPv6, if setup
- if (session[s].flags & SF_IPV6_ROUTED)
+ if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen)
route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
}
controlt *c = controlnew(14); // sending CDN
if (error)
{
- char buf[4];
+ uint8_t buf[4];
*(uint16_t *) buf = htons(result);
*(uint16_t *) (buf+2) = htons(error);
controlb(c, 1, buf, 4, 1);
if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
+ // clear PPP state
+ memset(&session[s].ppp, 0, sizeof(session[s].ppp));
+ sess_local[s].lcp.restart = 0;
+ sess_local[s].ipcp.restart = 0;
+ sess_local[s].ipv6cp.restart = 0;
+ sess_local[s].ccp.restart = 0;
+
cluster_send_session(s);
}
void sendipcp(tunnelidt t, sessionidt s)
{
uint8_t buf[MAXCONTROL];
- uint16_t r = sess_local[s].radius;
uint8_t *q;
CSTAT(sendipcp);
- if (!r)
- r = radiusnew(s);
-
- if (!r)
- {
- sessionshutdown(s, "No free RADIUS sessions for IPCP", 3, 0);
- return;
- }
-
- if (radius[r].state != RADIUSIPCP)
- {
- radius[r].state = RADIUSIPCP;
- radius[r].try = 0;
- }
-
- radius[r].retry = backoff(radius[r].try++);
- if (radius[r].try > 10)
+ if (!session[s].unique_id)
{
- radiusclear(r, s); // Clear radius session.
- sessionshutdown(s, "No reply to IPCP.", 3, 0);
- return;
+ if (!++last_id) ++last_id; // skip zero
+ session[s].unique_id = last_id;
}
q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPCP);
if (!q) return;
*q = ConfigReq;
- q[1] = r >> RADIUS_SHIFT; // ID, dont care, we only send one type of request
- *(uint16_t *) (q + 2) = htons(10);
- q[4] = 3;
- q[5] = 6;
+ q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
+ *(uint16_t *) (q + 2) = htons(10); // packet length
+ q[4] = 3; // ip address option
+ q[5] = 6; // option length
*(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
config->bind_address ? config->bind_address :
my_address; // send my IP
tunnelsend(buf, 10 + (q - buf), t); // send it
- session[s].flags &= ~SF_IPCP_ACKED; // Clear flag.
-
- // If we have an IPv6 prefix length configured, assume we should
- // try to negotiate an IPv6 session as well. Unless we've had a
- // (N)ACK for IPV6CP.
- if (config->ipv6_prefix.s6_addr[0] > 0 &&
- !(session[s].flags & SF_IPV6CP_ACKED) &&
- !(session[s].flags & SF_IPV6_NACKED))
- {
- q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPV6CP);
- if (!q) return;
-
- *q = ConfigReq;
- q[1] = r >> RADIUS_SHIFT; // ID, don't care, we
- // only send one type
- // of request
- *(uint16_t *) (q + 2) = htons(14);
- q[4] = 1;
- q[5] = 10;
- *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
- *(uint32_t *) (q + 10) = 0;
- q[13] = 1;
-
- tunnelsend(buf, 14 + (q - buf), t); // send it
- }
+}
+
+void sendipv6cp(tunnelidt t, sessionidt s)
+{
+ uint8_t buf[MAXCONTROL];
+ uint8_t *q;
+
+ CSTAT(sendipv6cp);
+
+ q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPV6CP);
+ if (!q) return;
+
+ *q = ConfigReq;
+ q[1] = session[s].unique_id & 0xf; // ID, don't care, we
+ // only send one type
+ // of request
+ *(uint16_t *) (q + 2) = htons(14);
+ q[4] = 1; // interface identifier option
+ q[5] = 10; // option length
+ *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
+ *(uint32_t *) (q + 10) = 0;
+ q[13] = 1;
+
+ tunnelsend(buf, 14 + (q - buf), t); // send it
}
static void sessionclear(sessionidt s)
controlt *c = controlnew(4); // sending StopCCN
if (error)
{
- char buf[64];
+ uint8_t buf[64];
int l = 4;
*(uint16_t *) buf = htons(result);
*(uint16_t *) (buf+2) = htons(error);
}
// read and process packet on tunnel (UDP)
-void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
+void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
{
- char *chapresponse = NULL;
+ uint8_t *chapresponse = NULL;
uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
uint8_t *p = buf + 2;
n = orig_len;
}
- LOG(4, s, t, " AVP %d (%s) len %d%s%s\n", mtype, avp_name(mtype), n,
+ LOG(4, s, t, " AVP %d (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
switch (mtype)
case 0: // message type
message = ntohs(*(uint16_t *) b);
mandatory = flags & 0x80;
- LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_message_type(message));
+ LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_code(message));
break;
case 1: // result code
{
const char* resdesc = "(unknown)";
if (message == 4)
{ /* StopCCN */
- resdesc = stopccn_result_code(rescode);
+ resdesc = l2tp_stopccn_result_code(rescode);
}
else if (message == 14)
{ /* CDN */
- resdesc = cdn_result_code(rescode);
+ resdesc = l2tp_cdn_result_code(rescode);
}
LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
if (n >= 4)
{
uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
- LOG(4, s, t, " Error Code %d: %s\n", errcode, error_code(errcode));
+ LOG(4, s, t, " Error Code %d: %s\n", errcode, l2tp_error_code(errcode));
}
if (n > 4)
LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
case 29: // Proxy Authentication Type
{
uint16_t atype = ntohs(*(uint16_t *)b);
- LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, auth_type(atype));
+ LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, ppp_auth_type(atype));
if (atype == 2)
authtype = AUTHCHAP;
else if (atype == 3)
case 10: // ICRQ
if (sessionfree && main_quit != QUIT_SHUTDOWN)
{
- uint16_t r;
+ controlt *c = controlnew(11); // ICRP
s = sessionfree;
sessionfree = session[s].next;
if (s > config->cluster_highest_sessionid)
config->cluster_highest_sessionid = s;
- // make a RADIUS session
- if ((r = radiusnew(s)))
- {
- controlt *c = controlnew(11); // sending ICRP
- session[s].opened = time_now;
- session[s].tunnel = t;
- session[s].far = asession;
- session[s].last_packet = time_now;
- LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
- control16(c, 14, s, 1); // assigned session
- controladd(c, t, asession); // send the reply
-
- strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
- strncpy(session[s].called, called, sizeof(session[s].called) - 1);
- strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
- STAT(session_created);
- break;
- }
+ session[s].opened = time_now;
+ session[s].tunnel = t;
+ session[s].far = asession;
+ session[s].last_packet = time_now;
+ LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
+ control16(c, 14, s, 1); // assigned session
+ controladd(c, t, asession); // send the reply
+ strncpy(session[s].called, called, sizeof(session[s].called) - 1);
+ strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
- LOG(1, s, t, "No free RADIUS sessions for ICRQ\n");
- sessionclear(s);
- }
- else
- {
- STAT(session_overflow);
- LOG(1, 0, t, "No free sessions\n");
+ session[s].ppp.phase = Establish;
+ session[s].ppp.lcp = Starting;
+
+ STAT(session_created);
+ break;
}
{
controlt *c = controlnew(14); // CDN
- if (main_quit == QUIT_SHUTDOWN)
- control16(c, 1, 2, 7); // try another
- else
+ if (!sessionfree)
+ {
+ STAT(session_overflow);
+ LOG(1, 0, t, "No free sessions\n");
control16(c, 1, 4, 0); // temporary lack of resources
+ }
+ else
+ control16(c, 1, 2, 7); // shutting down, try another
controladd(c, t, asession); // send the message
}
session[s].l2tp_flags = aflags; // set flags received
LOG(3, s, t, "Magic %X Flags %X\n", amagic, aflags);
controlnull(t); // ack
+
// proxy authentication type is not supported
if (!(config->radius_authtypes & authtype))
authtype = config->radius_authprefer;
// start LCP
sendlcp(t, s, authtype);
+ sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
+ sess_local[s].lcp.conf_sent = 1;
+ sess_local[s].lcp.nak_sent = 0;
+ sess_local[s].lcp_authtype = authtype;
+ session[s].ppp.lcp = RequestSent;
+
break;
case 14: // CDN
controlnull(t); // ack
}
else if (prot == PPPIPV6CP)
{
- if (config->ipv6_prefix.s6_addr[0] > 0)
- {
- session[s].last_packet = time_now;
- if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
- processipv6cp(t, s, p, l);
- }
- else
- {
- LOG(1, s, t, "IPv6 not configured; ignoring IPv6CP\n");
- }
+ session[s].last_packet = time_now;
+ if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
+ processipv6cp(t, s, p, l);
}
else if (prot == PPPCCP)
{
}
else if (prot == PPPIPV6)
{
- if (!config->ipv6_prefix.s6_addr[0] > 0)
+ if (!config->ipv6_prefix.s6_addr[0])
{
LOG(1, s, t, "IPv6 not configured; yet received IPv6 packet. Ignoring.\n");
return;
if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
processipout(buf, len);
else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
- && config->ipv6_prefix.s6_addr[0] > 0)
+ && config->ipv6_prefix.s6_addr[0])
processipv6out(buf, len);
// Else discard.
continue;
}
- if (session[s].ip && !(session[s].flags & SF_IPCP_ACKED)
- && !(sess_local[s].radius && radius[sess_local[s].radius].state == RADIUSIPCP))
+ // PPP timeouts
+ if (sess_local[s].lcp.restart >= time_now)
{
- // IPCP has not completed yet. Resend
- LOG(3, s, session[s].tunnel, "No ACK for initial IPCP ConfigReq... resending\n");
- sendipcp(session[s].tunnel, s);
- s_actions++;
+ int next_state = session[s].ppp.lcp;
+ switch (session[s].ppp.lcp)
+ {
+ case RequestSent:
+ case AckReceived:
+ next_state = RequestSent;
+
+ case AckSent:
+ if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
+ {
+ LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
+ sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
+ sess_local[s].lcp.conf_sent++;
+ sendlcp(t, s, sess_local[s].lcp_authtype);
+ change_state(s, lcp, next_state);
+ }
+ else
+ {
+ sessionshutdown(s, "No response to LCP ConfigReq.", 3, 0);
+ STAT(session_timeout);
+ }
+
+ s_actions++;
+ }
+
+ if (session[s].die)
+ continue;
+ }
+
+ if (sess_local[s].ipcp.restart >= time_now)
+ {
+ int next_state = session[s].ppp.ipcp;
+ switch (session[s].ppp.ipcp)
+ {
+ case RequestSent:
+ case AckReceived:
+ next_state = RequestSent;
+
+ case AckSent:
+ if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
+ {
+ LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
+ sess_local[s].ipcp.restart = time_now + config->ppp_restart_time;
+ sess_local[s].ipcp.conf_sent++;
+ sendipcp(t, s);
+ change_state(s, ipcp, next_state);
+ }
+ else
+ {
+ sessionshutdown(s, "No response to IPCP ConfigReq.", 3, 0);
+ STAT(session_timeout);
+ }
+
+ s_actions++;
+ }
+
+ if (session[s].die)
+ continue;
+ }
+
+ if (sess_local[s].ipv6cp.restart >= time_now)
+ {
+ int next_state = session[s].ppp.ipv6cp;
+ switch (session[s].ppp.ipv6cp)
+ {
+ case RequestSent:
+ case AckReceived:
+ next_state = RequestSent;
+
+ case AckSent:
+ if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
+ {
+ LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
+ sess_local[s].ipv6cp.restart = time_now + config->ppp_restart_time;
+ sess_local[s].ipv6cp.conf_sent++;
+ sendipv6cp(t, s);
+ change_state(s, ipv6cp, next_state);
+ }
+ else
+ {
+ LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
+ change_state(s, ipv6cp, Stopped);
+ }
+
+ s_actions++;
+ }
+ }
+
+ if (sess_local[s].ccp.restart >= time_now)
+ {
+ int next_state = session[s].ppp.ccp;
+ switch (session[s].ppp.ccp)
+ {
+ case RequestSent:
+ case AckReceived:
+ next_state = RequestSent;
+
+ case AckSent:
+ if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
+ {
+ LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
+ sess_local[s].ccp.restart = time_now + config->ppp_restart_time;
+ sess_local[s].ccp.conf_sent++;
+ sendccp(t, s);
+ change_state(s, ccp, next_state);
+ }
+ else
+ {
+ LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
+ change_state(s, ccp, Stopped);
+ }
+
+ s_actions++;
+ }
}
// Drop sessions who have not responded within IDLE_TIMEOUT seconds
}
// No data in ECHO_TIMEOUT seconds, send LCP ECHO
- if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
+ if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
{
uint8_t b[MAXCONTROL] = {0};
if (n)
{
struct sockaddr_in addr;
- int alen, c, s;
+ socklen_t alen;
+ int c, s;
int udp_ready = 0;
int tun_ready = 0;
int cluster_ready = 0;
config->num_tbfs = MAXTBFS;
config->rl_rate = 28; // 28kbps
config->cluster_master_min_adv = 1;
+ config->ppp_restart_time = 3;
+ config->ppp_max_configure = 10;
+ config->ppp_max_failure = 5;
strcpy(config->random_device, RANDOMDEVICE);
log_stream = stderr;
LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
}
-void snoop_send_packet(char *packet, uint16_t size, in_addr_t destination, uint16_t port)
+void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
{
struct sockaddr_in snoop_addr = {0};
if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
;
}
-static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response)
+static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
{
MD5_CTX ctx;
*challenge_response = NULL;
LOG(4, 0, 0, " Building challenge response for CHAP request\n");
- *challenge_response = (char *)calloc(17, 1);
+ *challenge_response = calloc(17, 1);
- MD5Init(&ctx);
- MD5Update(&ctx, &id, 1);
- MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
- MD5Update(&ctx, challenge, challenge_length);
- MD5Final(*challenge_response, &ctx);
+ MD5_Init(&ctx);
+ MD5_Update(&ctx, &id, 1);
+ MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
+ MD5_Update(&ctx, challenge, challenge_length);
+ MD5_Final(*challenge_response, &ctx);
return;
}
cache_ipmap(session[s].ip, s);
}
- if (!session[s].unique_id)
- {
- // did this session just finish radius?
- LOG(3, s, t, "Sending initial IPCP to client\n");
- sendipcp(t, s);
- session[s].unique_id = ++last_id;
- }
+ sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
+ lcp_open(t, s); // transition to Network phase and send initial IPCP
// Run the plugin's against this new session.
{
}
// check v6 routing
- if (new->flags & SF_IPV6_ROUTED && !(session[s].flags & SF_IPV6_ROUTED))
+ if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
// check filters
run_plugin_done(p);
}
-static void processcontrol(uint8_t * buf, int len, struct sockaddr_in *addr, int alen)
+static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen)
{
struct nsctl request;
struct nsctl response;
uint16_t m = htons(type);
// Compute initial pad
- MD5Init(&ctx);
- MD5Update(&ctx, (unsigned char *) &m, 2);
- MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
- MD5Update(&ctx, vector, vec_len);
- MD5Final(digest, &ctx);
+ MD5_Init(&ctx);
+ MD5_Update(&ctx, (unsigned char *) &m, 2);
+ MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
+ MD5_Update(&ctx, vector, vec_len);
+ MD5_Final(digest, &ctx);
// pointer to last decoded 16 octets
last = value;
// calculate a new pad based on the last decoded block
if (d >= sizeof(digest))
{
- MD5Init(&ctx);
- MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
- MD5Update(&ctx, last, sizeof(digest));
- MD5Final(digest, &ctx);
+ MD5_Init(&ctx);
+ MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
+ MD5_Update(&ctx, last, sizeof(digest));
+ MD5_Final(digest, &ctx);
d = 0;
last = value;