GitLab/ocserv
1
0
Fork 0
mirror of https://gitlab.com/openconnect/ocserv.git synced 2026-02-10 00:37:00 +08:00
Code Issues Packages Projects Releases Wiki Activity

corrected DTLS packet handling.

Browse Source
This commit is contained in:
Nikos Mavrogiannopoulos
2013-02-05 23:56:17 +01:00
parent 1e0bcc269d
commit 99824ebd94
8 changed files with 280 additions and 102 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
src/config.c
View File

@@ -204,6 +204,9 @@ int cmd_parser (int argc, char **argv, struct cfg_st* config)
if (HAVE_OPT(TLS_DEBUG))
config->tls_debug = 1;
if (HAVE_OPT(DEBUG))
config->debug = 1;
if (HAVE_OPT(CONFIG)) {
cfg_file = OPT_ARG(CONFIG);

3
src/log.c
View File

@@ -72,6 +72,9 @@ void __attribute__ ((format(printf, 3, 4)))
char ipbuf[128];
const char* ip;
va_list args;
if (priority == LOG_DEBUG && ws->config->debug == 0)
return;
ip = human_addr((void*)&ws->remote_addr, ws->remote_addr_len,
ipbuf, sizeof(ipbuf));

85
src/ocserv-args.c
View File

@@ -2,7 +2,7 @@
*
* DO NOT EDIT THIS FILE (ocserv-args.c)
*
* It has been AutoGen-ed February 5, 2013 at 09:21:04 PM by AutoGen 5.16
* It has been AutoGen-ed February 5, 2013 at 10:37:10 PM by AutoGen 5.16
* From the definitions ocserv-args.def
* and the template file options
*
@@ -65,7 +65,7 @@ extern FILE * option_usage_fp;
/*
* ocserv option static const strings
*/
static char const ocserv_opt_strs[1282] =
static char const ocserv_opt_strs[1340] =
/* 0 */ "ocserv\n"
"Copyright (C) 2013 Nikos Mavrogiannopoulos, all rights reserved.\n"
"This is free software. It is licensed for use, modification and\n"
@@ -86,21 +86,24 @@ static char const ocserv_opt_strs[1282] =
/* 854 */ "Enable verbose TLS debugging information.\0"
/* 896 */ "TLS_DEBUG\0"
/* 906 */ "tls-debug\0"
/* 916 */ "Configuration file for the server.\0"
/* 951 */ "CONFIG\0"
/* 958 */ "config\0"
/* 965 */ "Display extended usage information and exit\0"
/* 1009 */ "help\0"
/* 1014 */ "Extended usage information passed thru pager\0"
/* 1059 */ "more-help\0"
/* 1069 */ "OCSERV\0"
/* 1076 */ "ocserv - OpenConnect server\n"
/* 916 */ "Enable verbose network debugging information.\0"
/* 962 */ "DEBUG\0"
/* 968 */ "debug\0"
/* 974 */ "Configuration file for the server.\0"
/* 1009 */ "CONFIG\0"
/* 1016 */ "config\0"
/* 1023 */ "Display extended usage information and exit\0"
/* 1067 */ "help\0"
/* 1072 */ "Extended usage information passed thru pager\0"
/* 1117 */ "more-help\0"
/* 1127 */ "OCSERV\0"
/* 1134 */ "ocserv - OpenConnect server\n"
"USAGE: %s [ -<flag> [<val>] | --<name>[{=| }<val>] ]...\n\0"
/* 1162 */ "nmav@gnutls.org\0"
/* 1178 */ "\n\n\0"
/* 1181 */ "\n"
/* 1220 */ "nmav@gnutls.org\0"
/* 1236 */ "\n\n\0"
/* 1239 */ "\n"
"OpenConnect VPN server.\n\0"
/* 1207 */ "Usage: ocserv [options] -c [config]\n"
/* 1265 */ "Usage: ocserv [options] -c [config]\n"
"ocserv --help for usage instructions.\n";
/*
@@ -119,23 +122,31 @@ static char const ocserv_opt_strs[1282] =
#define TLS_DEBUG_name (ocserv_opt_strs+906)
#define TLS_DEBUG_FLAGS (OPTST_DISABLED)
/*
* debug option description:
*/
#define DEBUG_DESC (ocserv_opt_strs+916)
#define DEBUG_NAME (ocserv_opt_strs+962)
#define DEBUG_name (ocserv_opt_strs+968)
#define DEBUG_FLAGS (OPTST_DISABLED)
/*
* config option description:
*/
#define CONFIG_DESC (ocserv_opt_strs+916)
#define CONFIG_NAME (ocserv_opt_strs+951)
#define CONFIG_name (ocserv_opt_strs+958)
#define CONFIG_DESC (ocserv_opt_strs+974)
#define CONFIG_NAME (ocserv_opt_strs+1009)
#define CONFIG_name (ocserv_opt_strs+1016)
#define CONFIG_FLAGS (OPTST_DISABLED \
| OPTST_SET_ARGTYPE(OPARG_TYPE_FILE))
/*
* Help/More_Help option descriptions:
*/
#define HELP_DESC (ocserv_opt_strs+965)
#define HELP_name (ocserv_opt_strs+1009)
#define HELP_DESC (ocserv_opt_strs+1023)
#define HELP_name (ocserv_opt_strs+1067)
#ifdef HAVE_WORKING_FORK
#define MORE_HELP_DESC (ocserv_opt_strs+1014)
#define MORE_HELP_name (ocserv_opt_strs+1059)
#define MORE_HELP_DESC (ocserv_opt_strs+1072)
#define MORE_HELP_name (ocserv_opt_strs+1117)
#define MORE_HELP_FLAGS (OPTST_IMM | OPTST_NO_INIT)
#else
#define MORE_HELP_DESC NULL
@@ -184,8 +195,20 @@ static tOptDesc optDesc[OPTION_CT] = {
/* desc, NAME, name */ TLS_DEBUG_DESC, TLS_DEBUG_NAME, TLS_DEBUG_name,
/* disablement strs */ NULL, NULL },
{ /* entry idx, value */ 2, VALUE_OPT_CONFIG,
/* equiv idx, value */ 2, VALUE_OPT_CONFIG,
{ /* entry idx, value */ 2, VALUE_OPT_DEBUG,
/* equiv idx, value */ 2, VALUE_OPT_DEBUG,
/* equivalenced to */ NO_EQUIVALENT,
/* min, max, act ct */ 0, 1, 0,
/* opt state flags */ DEBUG_FLAGS, 0,
/* last opt argumnt */ { NULL }, /* --debug */
/* arg list/cookie */ NULL,
/* must/cannot opts */ NULL, NULL,
/* option proc */ NULL,
/* desc, NAME, name */ DEBUG_DESC, DEBUG_NAME, DEBUG_name,
/* disablement strs */ NULL, NULL },
{ /* entry idx, value */ 3, VALUE_OPT_CONFIG,
/* equiv idx, value */ 3, VALUE_OPT_CONFIG,
/* equivalenced to */ NO_EQUIVALENT,
/* min, max, act ct */ 0, 1, 0,
/* opt state flags */ CONFIG_FLAGS, 0,
@@ -226,13 +249,13 @@ static tOptDesc optDesc[OPTION_CT] = {
*
* Define the ocserv Option Environment
*/
#define zPROGNAME (ocserv_opt_strs+1069)
#define zUsageTitle (ocserv_opt_strs+1076)
#define zPROGNAME (ocserv_opt_strs+1127)
#define zUsageTitle (ocserv_opt_strs+1134)
#define zRcName NULL
#define apzHomeList NULL
#define zBugsAddr (ocserv_opt_strs+1162)
#define zExplain (ocserv_opt_strs+1178)
#define zDetail (ocserv_opt_strs+1181)
#define zBugsAddr (ocserv_opt_strs+1220)
#define zExplain (ocserv_opt_strs+1236)
#define zDetail (ocserv_opt_strs+1239)
#define zFullVersion (NULL)
/* extracted from optcode.tlib near line 350 */
@@ -247,7 +270,7 @@ static tOptDesc optDesc[OPTION_CT] = {
#define ocserv_full_usage (NULL)
#define ocserv_short_usage (ocserv_opt_strs+1207)
#define ocserv_short_usage (ocserv_opt_strs+1265)
#endif /* not defined __doxygen__ */
@@ -353,7 +376,7 @@ tOptions ocservOptions = {
NO_EQUIVALENT, /* '-#' option index */
NO_EQUIVALENT /* index of default opt */
},
5 /* full option count */, 3 /* user option count */,
6 /* full option count */, 4 /* user option count */,
ocserv_full_usage, ocserv_short_usage,
NULL, NULL,
PKGDATADIR, ocserv_packager_info

7
src/ocserv-args.def
View File

@@ -33,6 +33,13 @@ flag = {
doc = "";
};
flag = {
name = debug;
value = d;
descrip = "Enable verbose network debugging information.";
doc = "";
};
flag = {
name = config;
value = c;

12
src/ocserv-args.h
View File

@@ -2,7 +2,7 @@
*
* DO NOT EDIT THIS FILE (ocserv-args.h)
*
* It has been AutoGen-ed February 5, 2013 at 09:21:04 PM by AutoGen 5.16
* It has been AutoGen-ed February 5, 2013 at 10:37:10 PM by AutoGen 5.16
* From the definitions ocserv-args.def
* and the template file options
*
@@ -68,12 +68,13 @@
typedef enum {
INDEX_OPT_FOREGROUND = 0,
INDEX_OPT_TLS_DEBUG = 1,
INDEX_OPT_CONFIG = 2,
INDEX_OPT_HELP = 3,
INDEX_OPT_MORE_HELP = 4
INDEX_OPT_DEBUG = 2,
INDEX_OPT_CONFIG = 3,
INDEX_OPT_HELP = 4,
INDEX_OPT_MORE_HELP = 5
} teOptIndex;
#define OPTION_CT 5
#define OPTION_CT 6
/*
* Interface defines for all options. Replace "n" with the UPPER_CASED
@@ -111,6 +112,7 @@ typedef enum {
*/
#define VALUE_OPT_FOREGROUND 'f'
#define VALUE_OPT_TLS_DEBUG 1
#define VALUE_OPT_DEBUG 'd'
#define VALUE_OPT_CONFIG 'c'
#define VALUE_OPT_HELP 'h'
#define VALUE_OPT_MORE_HELP '!'

1
src/vpn.h
View File

@@ -60,6 +60,7 @@ struct cfg_st {
const char *cookie_db;
unsigned foreground;
unsigned tls_debug;
unsigned debug;
unsigned max_clients;
const char *connect_script;

2
src/worker-auth.c
View File

@@ -268,6 +268,8 @@ int auth_cookie(worker_st *ws, void* cookie, size_t cookie_size)
int ret;
struct cmd_auth_cookie_req_st areq;
memset(&areq, 0, sizeof(areq));
if (cookie_size != sizeof(areq.cookie))
return -1;

269
src/worker-vpn.c
View File

@@ -58,7 +58,9 @@
#define MAX_HTTP_REQUESTS 8
static int handle_worker_commands(struct worker_st *ws);
static int parse_cstp_data(struct worker_st* ws, gnutls_session_t, uint8_t* buf, size_t buf_size);
static int parse_cstp_data(struct worker_st* ws, uint8_t* buf, size_t buf_size);
static int parse_dtls_data(struct worker_st* ws,
uint8_t* buf, size_t buf_size);
static void handle_alarm(int signo)
{
@@ -120,8 +122,6 @@ int url_cb(http_parser* parser, const char *at, size_t length)
memcpy(req->url, at, length);
req->url[length] = 0;
//fprintf(stderr, "request %s %s\n", http_method_str(parser->method), req->url);
return 0;
}
@@ -189,6 +189,11 @@ size_t nlen;
nlen = sizeof(req->cookie);
gnutls_hex2bin(p, length, req->cookie, &nlen);
if (nlen < COOKIE_SIZE) {
req->cookie_set = 0;
return 0;
}
req->cookie_set = 1;
break;
}
@@ -240,6 +245,7 @@ uint8_t buffer[512];
ssize_t buffer_size;
gnutls_datum_t master = { ws->master_secret, sizeof(ws->master_secret) };
gnutls_datum_t sid = { ws->session_id, sizeof(ws->session_id) };
unsigned port;
/* first receive from the correct client and connect socket */
cli_addr_size = sizeof(cli_addr);
@@ -248,7 +254,14 @@ gnutls_datum_t sid = { ws->session_id, sizeof(ws->session_id) };
oclog(ws, LOG_ERR, "Error receiving in UDP socket");
return -1;
}
if (cli_addr_size == sizeof(struct sockaddr_in6)) {
port = SA_IN6_PORT(&cli_addr);
} else {
port = SA_IN_PORT(&cli_addr);
}
port = ntohs(port);
buffer_size = ret;
if ( (ws->remote_addr_len == sizeof(struct sockaddr_in) && memcmp(SA_IN_P(&cli_addr),
@@ -257,12 +270,15 @@ gnutls_datum_t sid = { ws->session_id, sizeof(ws->session_id) };
SA_IN6_P(&ws->remote_addr), sizeof(struct in6_addr)) == 0)) {
/* connect to host */
#if 1
oclog(ws, LOG_ERR, "Connecting to UDP port %u", port);
ret = connect(ws->udp_fd, (void*)&cli_addr, cli_addr_size);
if (ret < 0) {
e = errno;
oclog(ws, LOG_ERR, "Error connecting: %s", strerror(e));
return -1;
}
#endif
} else {
/* received packet from unknown host */
@@ -450,6 +466,33 @@ finish:
tls_close(session);
}
static int set_tun_mtu(struct worker_st* ws, unsigned mtu)
{
int fd, ret, e;
struct ifreq ifr;
fd = socket(AF_INET, SOCK_STREAM, 0);
if (fd == -1)
return -1;
memset(&ifr, 0, sizeof(ifr));
snprintf(ifr.ifr_name, IFNAMSIZ, "%s", ws->tun_name);
ifr.ifr_mtu = mtu;
ret = ioctl(fd, SIOCSIFMTU, &ifr);
if (ret != 0) {
e = errno;
oclog(ws, LOG_DEBUG, "ioctl SIOCSIFMTU error: %s", strerror(e));
ret = -1;
goto fail;
}
ret = 0;
fail:
close(fd);
return ret;
}
/* if local is non zero it returns the local, otherwise the remote */
static int get_ip(struct worker_st* ws, int fd, int family, unsigned int local,
struct vpn_st* vinfo, char** buffer, size_t* buffer_size)
@@ -707,6 +750,54 @@ const uint8_t * p = buf;
return len;
}
/* sets the provided value of mtu as bad,
* and returns an estimation of good.
*
* Returns -1 on failure.
*/
static
int mtu_not_ok(worker_st* ws, unsigned *mtu)
{
ws->last_bad_mtu = *mtu;
ws->last_good_mtu = (*mtu)/2;
if (ws->last_good_mtu < 128)
return -1;
*mtu = ws->last_good_mtu;
gnutls_dtls_set_data_mtu (ws->dtls_session, *mtu);
set_tun_mtu(ws, *mtu);
return 0;
}
static void mtu_set(worker_st *ws, unsigned max_mtu)
{
if (ws->last_good_mtu == 0)
ws->last_good_mtu = max_mtu;
if (ws->last_bad_mtu == 0)
ws->last_bad_mtu = max_mtu;
}
static
void mtu_ok(worker_st* ws, unsigned sent, unsigned *mtu)
{
int c;
if (sent < *mtu || ws->last_bad_mtu == (*mtu)+1)
return;
c = (ws->last_good_mtu + ws->last_bad_mtu)/2;
*mtu = c;
gnutls_dtls_set_data_mtu (ws->dtls_session, c);
set_tun_mtu(ws, c);
return;
}
static int connect_handler(worker_st *ws)
{
int ret;
@@ -717,12 +808,11 @@ int max;
unsigned i;
struct vpn_st vinfo;
uint8_t buffer[16*1024];
unsigned int buffer_size;
unsigned int buffer_size, tls_retry;
char *p;
unsigned tls_pending, dtls_pending = 0;
time_t udp_recv_time = 0;
unsigned mtu_overhead, effective_mtu = 0;
gnutls_session_t ts;
unsigned mtu_overhead, dtls_mtu = 0;
if (req->cookie_set == 0) {
oclog(ws, LOG_INFO, "Connect request without authentication");
@@ -833,9 +923,9 @@ gnutls_session_t ts;
mtu_overhead = 20+8;
else
mtu_overhead = 40+8;
effective_mtu = vinfo.mtu - mtu_overhead;
dtls_mtu = vinfo.mtu - mtu_overhead;
tls_printf(ws->session, "X-DTLS-MTU: %u\r\n", effective_mtu);
tls_printf(ws->session, "X-DTLS-MTU: %u\r\n", dtls_mtu);
}
tls_puts(ws->session, "X-CSTP-Banner: Welcome\r\n");
@@ -866,15 +956,13 @@ gnutls_session_t ts;
}
if (FD_ISSET(ws->tun_fd, &rfds)) {
if (ws->udp_state == UP_ACTIVE) {
l = effective_mtu;
ts = ws->dtls_session;
l = dtls_mtu;
} else {
l = sizeof(buffer);
ts = ws->session;
}
l = read(ws->tun_fd, buffer + 8, l - 8);
if (l < 0) {
e = errno;
@@ -891,31 +979,48 @@ gnutls_session_t ts;
exit(1);
}
buffer[0] = 'S';
buffer[1] = 'T';
buffer[2] = 'F';
buffer[3] = 1;
buffer[4] = l >> 8;
buffer[5] = l & 0xff;
buffer[6] = 0;
buffer[7] = 0;
tls_retry = 0;
oclog(ws, LOG_DEBUG, "Sending %d\n", l);
if (ws->udp_state == UP_ACTIVE) {
buffer[7] = AC_PKT_DATA;
ret = tls_send(ts, buffer, l + 8);
GNUTLS_FATAL_ERR(ret);
ret = tls_send(ws->dtls_session, buffer + 7, l + 1);
GNUTLS_FATAL_ERR(ret);
if (ret == GNUTLS_E_LARGE_PACKET) {
/* XXX: we have to do something better than that.
* adjust mtu */
if (effective_mtu > 128)
effective_mtu -= 32;
if (ret == GNUTLS_E_LARGE_PACKET) {
ret = mtu_not_ok(ws, &dtls_mtu);
if (ret < 0) {
oclog(ws, LOG_INFO, "Could not calculate an MTU. Disabling DTLS.");
ws->udp_state = UP_DISABLED;
}
oclog(ws, LOG_DEBUG, "Retrying (TLS) %d\n", l);
tls_retry = 1;
} else if (ret > 0) {
mtu_ok(ws, ret, &dtls_mtu);
}
}
if (ws->udp_state != UP_ACTIVE || tls_retry != 0) {
buffer[0] = 'S';
buffer[1] = 'T';
buffer[2] = 'F';
buffer[3] = 1;
buffer[4] = l >> 8;
buffer[5] = l & 0xff;
buffer[6] = AC_PKT_DATA;
buffer[7] = 0;
ret = tls_send(ws->session, buffer, l + 8);
GNUTLS_FATAL_ERR(ret);
}
}
if (FD_ISSET(ws->conn_fd, &rfds) || tls_pending != 0) {
ret = tls_recv(ws->session, buffer, sizeof(buffer));
oclog(ws, LOG_DEBUG, "Received %d bytes (TLS)\n", ret);
GNUTLS_FATAL_ERR(ret);
if (ret == 0) { /* disconnect */
@@ -925,7 +1030,7 @@ gnutls_session_t ts;
l = ret;
ret = parse_cstp_data(ws, ws->session, buffer, l);
ret = parse_cstp_data(ws, buffer, l);
if (ret < 0) {
oclog(ws, LOG_INFO, "Error parsing CSTP data");
exit(1);
@@ -944,6 +1049,8 @@ gnutls_session_t ts;
case UP_ACTIVE:
case UP_INACTIVE:
ret = tls_recv(ws->dtls_session, buffer, sizeof(buffer));
oclog(ws, LOG_DEBUG, "Received %d bytes (DTLS)\n", ret);
GNUTLS_FATAL_ERR(ret);
@@ -955,7 +1062,7 @@ gnutls_session_t ts;
ws->udp_state = UP_ACTIVE;
ret = parse_cstp_data(ws, ws->dtls_session, buffer, l);
ret = parse_dtls_data(ws, buffer, l);
if (ret < 0) {
oclog(ws, LOG_INFO, "Error parsing CSTP data");
exit(1);
@@ -968,9 +1075,12 @@ gnutls_session_t ts;
if (ret < 0)
exit(1);
gnutls_dtls_set_mtu (ws->dtls_session, effective_mtu);
gnutls_dtls_set_mtu (ws->dtls_session, dtls_mtu);
mtu_set(ws, dtls_mtu);
break;
case UP_HANDSHAKE:
hsk_restart:
ret = gnutls_handshake(ws->dtls_session);
if (ret < 0 && gnutls_error_is_fatal(ret) != 0) {
oclog(ws, LOG_ERR, "Error in DTLS handshake: %s\n", gnutls_strerror(ret));
@@ -980,15 +1090,20 @@ gnutls_session_t ts;
if (ret == GNUTLS_E_LARGE_PACKET) {
/* adjust mtu */
if (effective_mtu > 256)
effective_mtu -= 128;
ret = mtu_not_ok(ws, &dtls_mtu);
if (dtls_mtu < 0) {
oclog(ws, LOG_DEBUG, "DTLS handshake failed. MTU error\n");
} else {
goto hsk_restart;
}
}
if (ret == 0) {
ws->udp_state = UP_ACTIVE;
effective_mtu = gnutls_dtls_get_data_mtu(ws->dtls_session);
oclog(ws, LOG_DEBUG, "DTLS handshake complete (MTU: %u)\n", effective_mtu);
dtls_mtu = gnutls_dtls_get_data_mtu(ws->dtls_session);
mtu_set(ws, dtls_mtu);
oclog(ws, LOG_DEBUG, "DTLS handshake completed (MTU: %u)\n", dtls_mtu);
}
break;
@@ -1057,11 +1172,49 @@ int handle_worker_commands(struct worker_st *ws)
return 0;
}
static int parse_data(struct worker_st* ws,
gnutls_session_t ts, /* the interface of recv */
uint8_t head,
uint8_t* buf, size_t buf_size)
{
int ret, e;
switch (head) {
case AC_PKT_DPD_RESP:
case AC_PKT_KEEPALIVE:
break;
case AC_PKT_DPD_OUT:
oclog(ws, LOG_DEBUG, "Sending STF8\n");
ret =
tls_send(ts, "STF\x01\x00\x00\x04\x00", 8);
if (ret < 0) {
oclog(ws, LOG_ERR, "Could not send TLS data: %s", gnutls_strerror(ret));
return -1;
}
break;
case AC_PKT_DISCONN:
oclog(ws, LOG_INFO, "Received BYE packet\n");
break;
case AC_PKT_DATA:
oclog(ws, LOG_DEBUG, "Writing %d bytes to TUN\n", (int)buf_size);
ret = tun_write(ws->tun_fd, buf, buf_size);
if (ret == -1) {
e = errno;
oclog(ws, LOG_ERR, "Could not write data to tun: %s", strerror(e));
return -1;
}
break;
}
return head;
}
static int parse_cstp_data(struct worker_st* ws,
gnutls_session_t ts, /* the interface of recv */
uint8_t* buf, size_t buf_size)
{
int pktlen, ret, e;
int pktlen;
if (buf_size < 8) {
oclog(ws, LOG_INFO, "Can't read CSTP header (only %d bytes are available)\n", (int)buf_size);
@@ -1080,32 +1233,16 @@ int pktlen, ret, e;
return -1;
}
switch (buf[6]) {
case AC_PKT_DPD_RESP:
case AC_PKT_KEEPALIVE:
break;
case AC_PKT_DPD_OUT:
ret =
tls_send(ts, "STF\x01\x00\x00\x04\x00", 8);
if (ret < 0) {
oclog(ws, LOG_ERR, "Could not send TLS data: %s", gnutls_strerror(ret));
return -1;
}
break;
case AC_PKT_DISCONN:
oclog(ws, LOG_INFO, "Received BYE packet\n");
break;
case AC_PKT_DATA:
ret = tun_write(ws->tun_fd, buf + 8, pktlen);
if (ret == -1) {
e = errno;
oclog(ws, LOG_ERR, "Could not write data to tun: %s", strerror(e));
return -1;
}
break;
}
return buf[6];
return parse_data(ws, ws->session, buf[6], buf+8, pktlen);
}
static int parse_dtls_data(struct worker_st* ws,
uint8_t* buf, size_t buf_size)
{
if (buf_size < 1) {
oclog(ws, LOG_INFO, "Can't read DTLS header (only %d bytes are available)\n", (int)buf_size);
return -1;
}
return parse_data(ws, ws->dtls_session, buf[0], buf+1, buf_size-1);
}