svr-runopts.c - third_party/dropbear - Git at Google

 /*
  * Dropbear - a SSH2 server
  *
  * Copyright (c) 2002,2003 Matt Johnston
  * All rights reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE. */

 #include "includes.h"
 #include "runopts.h"
 #include "signkey.h"
 #include "buffer.h"
 #include "dbutil.h"
 #include "algo.h"

 svr_runopts svr_opts; /* GLOBAL */

 static void printhelp(const char * progname);
 static void addportandaddress(char* spec);

 static void printhelp(const char * progname) {

 	fprintf(stderr, "Dropbear server v%s https://matt.ucc.asn.au/dropbear/dropbear.html\n"
 					"Usage: %s [options]\n"
 					"-b bannerfile	Display the contents of bannerfile"
 					" before user login\n"
 					"		(default: none)\n"
 #ifdef DROPBEAR_DSS
 					"-d dsskeyfile	Use dsskeyfile for the DSS host key\n"
 					"		(default: %s)\n"
 #endif
 #ifdef DROPBEAR_RSA
 					"-r rsakeyfile	Use rsakeyfile for the RSA host key\n"
 					"		(default: %s)\n"
 #endif
 					"-F		Don't fork into background\n"
 #ifdef DISABLE_SYSLOG
 					"(Syslog support not compiled in, using stderr)\n"
 #else
 					"-E		Log to stderr rather than syslog\n"
 #endif
 #ifdef DO_MOTD
 					"-m		Don't display the motd on login\n"
 #endif
 					"-w		Disallow root logins\n"
 #if defined(ENABLE_SVR_PASSWORD_AUTH) || defined(ENABLE_SVR_PAM_AUTH)
 					"-s		Disable password logins\n"
 					"-g		Disable password logins for root\n"
 					"-B		Allow blank password logins\n"
 #endif
 #ifdef ENABLE_SVR_LOCALTCPFWD
 					"-j		Disable local port forwarding\n"
 #endif
 #ifdef ENABLE_SVR_REMOTETCPFWD
 					"-k		Disable remote port forwarding\n"
 					"-a		Allow connections to forwarded ports from any host\n"
 #endif
 					"-p [address:]port\n"
 					"		Listen on specified tcp port (and optionally address),\n"
 					"		up to %d can be specified\n"
 					"		(default port is %s if none specified)\n"
 					"-P PidFile	Create pid file PidFile\n"
 					"		(default %s)\n"
 #ifdef INETD_MODE
 					"-i		Start for inetd\n"
 #endif
 					"-W <receive_window_buffer> (default %d, larger may be faster, max 1MB)\n"
 					"-K <keepalive>  (0 is never, default %d, in seconds)\n"
 					"-I <idle_timeout>  (0 is never, default %d, in seconds)\n"
 #ifdef DEBUG_TRACE
 					"-v		verbose (compiled with DEBUG_TRACE)\n"
 #endif
 					,DROPBEAR_VERSION, progname,
 #ifdef DROPBEAR_DSS
 					DSS_PRIV_FILENAME,
 #endif
 #ifdef DROPBEAR_RSA
 					RSA_PRIV_FILENAME,
 #endif
 					DROPBEAR_MAX_PORTS, DROPBEAR_DEFPORT, DROPBEAR_PIDFILE,
 					DEFAULT_RECV_WINDOW, DEFAULT_KEEPALIVE, DEFAULT_IDLE_TIMEOUT);
 }

 void svr_getopts(int argc, char ** argv) {

 	unsigned int i;
 	char ** next = 0;
 	int nextisport = 0;
 	char* recv_window_arg = NULL;
 	char* keepalive_arg = NULL;
 	char* idle_timeout_arg = NULL;

 	/* see printhelp() for options */
 	svr_opts.rsakeyfile = NULL;
 	svr_opts.dsskeyfile = NULL;
 	svr_opts.bannerfile = NULL;
 	svr_opts.banner = NULL;
 	svr_opts.forkbg = 1;
 	svr_opts.norootlogin = 0;
 	svr_opts.noauthpass = 0;
 	svr_opts.norootpass = 0;
 	svr_opts.allowblankpass = 0;
 	svr_opts.inetdmode = 0;
 	svr_opts.portcount = 0;
 	svr_opts.hostkey = NULL;
 	svr_opts.pidfile = DROPBEAR_PIDFILE;
 #ifdef ENABLE_SVR_LOCALTCPFWD
 	svr_opts.nolocaltcp = 0;
 #endif
 #ifdef ENABLE_SVR_REMOTETCPFWD
 	svr_opts.noremotetcp = 0;
 #endif
 #ifndef DISABLE_ZLIB
 	opts.enable_compress = 1;
 #endif
 	/* not yet
 	opts.ipv4 = 1;
 	opts.ipv6 = 1;
 	*/
 #ifdef DO_MOTD
 	svr_opts.domotd = 1;
 #endif
 #ifndef DISABLE_SYSLOG
 	svr_opts.usingsyslog = 1;
 #endif
 	opts.recv_window = DEFAULT_RECV_WINDOW;
 	opts.keepalive_secs = DEFAULT_KEEPALIVE;
 	opts.idle_timeout_secs = DEFAULT_IDLE_TIMEOUT;

 #ifdef ENABLE_SVR_REMOTETCPFWD
 	opts.listen_fwd_all = 0;
 #endif

 	for (i = 1; i < (unsigned int)argc; i++) {
 		if (nextisport) {
 			addportandaddress(argv[i]);
 			nextisport = 0;
 			continue;
 		}

 		if (next) {
 			*next = argv[i];
 			if (*next == NULL) {
 				dropbear_exit("Invalid null argument");
 			}
 			next = 0x00;
 			continue;
 		}

 		if (argv[i][0] == '-') {
 			switch (argv[i][1]) {
 				case 'b':
 					next = &svr_opts.bannerfile;
 					break;
 #ifdef DROPBEAR_DSS
 				case 'd':
 					next = &svr_opts.dsskeyfile;
 					break;
 #endif
 #ifdef DROPBEAR_RSA
 				case 'r':
 					next = &svr_opts.rsakeyfile;
 					break;
 #endif
 				case 'F':
 					svr_opts.forkbg = 0;
 					break;
 #ifndef DISABLE_SYSLOG
 				case 'E':
 					svr_opts.usingsyslog = 0;
 					break;
 #endif
 #ifdef ENABLE_SVR_LOCALTCPFWD
 				case 'j':
 					svr_opts.nolocaltcp = 1;
 					break;
 #endif
 #ifdef ENABLE_SVR_REMOTETCPFWD
 				case 'k':
 					svr_opts.noremotetcp = 1;
 					break;
 				case 'a':
 					opts.listen_fwd_all = 1;
 					break;
 #endif
 #ifdef INETD_MODE
 				case 'i':
 					svr_opts.inetdmode = 1;
 					break;
 #endif
 				case 'p':
 				  nextisport = 1;
 				  break;
 				case 'P':
 					next = &svr_opts.pidfile;
 					break;
 #ifdef DO_MOTD
 				/* motd is displayed by default, -m turns it off */
 				case 'm':
 					svr_opts.domotd = 0;
 					break;
 #endif
 				case 'w':
 					svr_opts.norootlogin = 1;
 					break;
 				case 'W':
 					next = &recv_window_arg;
 					break;
 				case 'K':
 					next = &keepalive_arg;
 					break;
 				case 'I':
 					next = &idle_timeout_arg;
 					break;
 #if defined(ENABLE_SVR_PASSWORD_AUTH) || defined(ENABLE_SVR_PAM_AUTH)
 				case 's':
 					svr_opts.noauthpass = 1;
 					break;
 				case 'g':
 					svr_opts.norootpass = 1;
 					break;
 				case 'B':
 					svr_opts.allowblankpass = 1;
 					break;
 #endif
 				case 'h':
 					printhelp(argv[0]);
 					exit(EXIT_FAILURE);
 					break;
 				case 'u':
 					/* backwards compatibility with old urandom option */
 					break;
 #ifdef DEBUG_TRACE
 				case 'v':
 					debug_trace = 1;
 					break;
 #endif
 				default:
 					fprintf(stderr, "Unknown argument %s\n", argv[i]);
 					printhelp(argv[0]);
 					exit(EXIT_FAILURE);
 					break;
 			}
 		}
 	}

 	/* Set up listening ports */
 	if (svr_opts.portcount == 0) {
 		svr_opts.ports[0] = m_strdup(DROPBEAR_DEFPORT);
 		svr_opts.addresses[0] = m_strdup(DROPBEAR_DEFADDRESS);
 		svr_opts.portcount = 1;
 	}

 	if (svr_opts.dsskeyfile == NULL) {
 		svr_opts.dsskeyfile = DSS_PRIV_FILENAME;
 	}
 	if (svr_opts.rsakeyfile == NULL) {
 		svr_opts.rsakeyfile = RSA_PRIV_FILENAME;
 	}

 	if (svr_opts.bannerfile) {
 		struct stat buf;
 		if (stat(svr_opts.bannerfile, &buf) != 0) {
 			dropbear_exit("Error opening banner file '%s'",
 					svr_opts.bannerfile);
 		}

 		if (buf.st_size > MAX_BANNER_SIZE) {
 			dropbear_exit("Banner file too large, max is %d bytes",
 					MAX_BANNER_SIZE);
 		}

 		svr_opts.banner = buf_new(buf.st_size);
 		if (buf_readfile(svr_opts.banner, svr_opts.bannerfile)!=DROPBEAR_SUCCESS) {
 			dropbear_exit("Error reading banner file '%s'",
 					svr_opts.bannerfile);
 		}
 		buf_setpos(svr_opts.banner, 0);

 	}

 	if (recv_window_arg) {
 		opts.recv_window = atol(recv_window_arg);
 		if (opts.recv_window == 0 || opts.recv_window > MAX_RECV_WINDOW) {
 			dropbear_exit("Bad recv window '%s'", recv_window_arg);
 		}
 	}

 	if (keepalive_arg) {
 		unsigned int val;
 		if (m_str_to_uint(keepalive_arg, &val) == DROPBEAR_FAILURE) {
 			dropbear_exit("Bad keepalive '%s'", keepalive_arg);
 		}
 		opts.keepalive_secs = val;
 	}

 	if (idle_timeout_arg) {
 		unsigned int val;
 		if (m_str_to_uint(idle_timeout_arg, &val) == DROPBEAR_FAILURE) {
 			dropbear_exit("Bad idle_timeout '%s'", idle_timeout_arg);
 		}
 		opts.idle_timeout_secs = val;
 	}
 }

 static void addportandaddress(char* spec) {

 	char *myspec = NULL;

 	if (svr_opts.portcount < DROPBEAR_MAX_PORTS) {

 		/* We don't free it, it becomes part of the runopt state */
 		myspec = m_strdup(spec);

 		if (myspec[0] == '[') {
 			myspec++;
 			svr_opts.ports[svr_opts.portcount] = strchr(myspec, ']');
 			if (svr_opts.ports[svr_opts.portcount] == NULL) {
 				/* Unmatched [ -> exit */
 				dropbear_exit("Bad listen address");
 			}
 			svr_opts.ports[svr_opts.portcount][0] = '\0';
 			svr_opts.ports[svr_opts.portcount]++;
 			if (svr_opts.ports[svr_opts.portcount][0] != ':') {
 				/* Missing port -> exit */
 				dropbear_exit("Missing port");
 			}
 		} else {
 			/* search for ':', that separates address and port */
 			svr_opts.ports[svr_opts.portcount] = strrchr(myspec, ':');
 		}

 		if (svr_opts.ports[svr_opts.portcount] == NULL) {
 			/* no ':' -> the whole string specifies just a port */
 			svr_opts.ports[svr_opts.portcount] = myspec;
 		} else {
 			/* Split the address/port */
 			svr_opts.ports[svr_opts.portcount][0] = '\0';
 			svr_opts.ports[svr_opts.portcount]++;
 			svr_opts.addresses[svr_opts.portcount] = myspec;
 		}

 		if (svr_opts.addresses[svr_opts.portcount] == NULL) {
 			/* no address given -> fill in the default address */
 			svr_opts.addresses[svr_opts.portcount] = m_strdup(DROPBEAR_DEFADDRESS);
 		}

 		if (svr_opts.ports[svr_opts.portcount][0] == '\0') {
 			/* empty port -> exit */
 			dropbear_exit("Bad port");
 		}

 		svr_opts.portcount++;
 	}
 }

 static void disablekey(int type, const char* filename) {

 	int i;

 	for (i = 0; sshhostkey[i].name != NULL; i++) {
 		if (sshhostkey[i].val == type) {
 			sshhostkey[i].usable = 0;
 			break;
 		}
 	}
 	dropbear_log(LOG_WARNING, "Failed reading '%s', disabling %s", filename,
 			type == DROPBEAR_SIGNKEY_DSS ? "DSS" : "RSA");
 }

 /* Must be called after syslog/etc is working */
 void loadhostkeys() {

 	int ret;
 	int type;

 	TRACE(("enter loadhostkeys"))

 	svr_opts.hostkey = new_sign_key();

 #ifdef DROPBEAR_RSA
 	type = DROPBEAR_SIGNKEY_RSA;
 	ret = readhostkey(svr_opts.rsakeyfile, svr_opts.hostkey, &type);
 	if (ret == DROPBEAR_FAILURE) {
 		disablekey(DROPBEAR_SIGNKEY_RSA, svr_opts.rsakeyfile);
 	}
 #endif
 #ifdef DROPBEAR_DSS
 	type = DROPBEAR_SIGNKEY_DSS;
 	ret = readhostkey(svr_opts.dsskeyfile, svr_opts.hostkey, &type);
 	if (ret == DROPBEAR_FAILURE) {
 		disablekey(DROPBEAR_SIGNKEY_DSS, svr_opts.dsskeyfile);
 	}
 #endif

 	if ( 1
 #ifdef DROPBEAR_DSS
 		&& svr_opts.hostkey->dsskey == NULL
 #endif
 #ifdef DROPBEAR_RSA
 		&& svr_opts.hostkey->rsakey == NULL
 #endif
 		) {
 		dropbear_exit("No hostkeys available");
 	}

 	TRACE(("leave loadhostkeys"))
 }
	/*
	* Dropbear - a SSH2 server
	*
	* Copyright (c) 2002,2003 Matt Johnston
	* All rights reserved.
	*
	* Permission is hereby granted, free of charge, to any person obtaining a copy
	* of this software and associated documentation files (the "Software"), to deal
	* in the Software without restriction, including without limitation the rights
	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	* copies of the Software, and to permit persons to whom the Software is
	* furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be included in
	* all copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	* SOFTWARE. */

	#include "includes.h"
	#include "runopts.h"
	#include "signkey.h"
	#include "buffer.h"
	#include "dbutil.h"
	#include "algo.h"

	svr_runopts svr_opts; /* GLOBAL */

	static void printhelp(const char * progname);
	static void addportandaddress(char* spec);

	static void printhelp(const char * progname) {

	fprintf(stderr, "Dropbear server v%s https://matt.ucc.asn.au/dropbear/dropbear.html\n"
	"Usage: %s [options]\n"
	"-b bannerfile Display the contents of bannerfile"
	" before user login\n"
	" (default: none)\n"
	#ifdef DROPBEAR_DSS
	"-d dsskeyfile Use dsskeyfile for the DSS host key\n"
	" (default: %s)\n"
	#endif
	#ifdef DROPBEAR_RSA
	"-r rsakeyfile Use rsakeyfile for the RSA host key\n"
	" (default: %s)\n"
	#endif
	"-F Don't fork into background\n"
	#ifdef DISABLE_SYSLOG
	"(Syslog support not compiled in, using stderr)\n"
	#else
	"-E Log to stderr rather than syslog\n"
	#endif
	#ifdef DO_MOTD
	"-m Don't display the motd on login\n"
	#endif
	"-w Disallow root logins\n"
	#if defined(ENABLE_SVR_PASSWORD_AUTH) \|\| defined(ENABLE_SVR_PAM_AUTH)
	"-s Disable password logins\n"
	"-g Disable password logins for root\n"
	"-B Allow blank password logins\n"
	#endif
	#ifdef ENABLE_SVR_LOCALTCPFWD
	"-j Disable local port forwarding\n"
	#endif
	#ifdef ENABLE_SVR_REMOTETCPFWD
	"-k Disable remote port forwarding\n"
	"-a Allow connections to forwarded ports from any host\n"
	#endif
	"-p [address:]port\n"
	" Listen on specified tcp port (and optionally address),\n"
	" up to %d can be specified\n"
	" (default port is %s if none specified)\n"
	"-P PidFile Create pid file PidFile\n"
	" (default %s)\n"
	#ifdef INETD_MODE
	"-i Start for inetd\n"
	#endif
	"-W <receive_window_buffer> (default %d, larger may be faster, max 1MB)\n"
	"-K <keepalive> (0 is never, default %d, in seconds)\n"
	"-I <idle_timeout> (0 is never, default %d, in seconds)\n"
	#ifdef DEBUG_TRACE
	"-v verbose (compiled with DEBUG_TRACE)\n"
	#endif
	,DROPBEAR_VERSION, progname,
	#ifdef DROPBEAR_DSS
	DSS_PRIV_FILENAME,
	#endif
	#ifdef DROPBEAR_RSA
	RSA_PRIV_FILENAME,
	#endif
	DROPBEAR_MAX_PORTS, DROPBEAR_DEFPORT, DROPBEAR_PIDFILE,
	DEFAULT_RECV_WINDOW, DEFAULT_KEEPALIVE, DEFAULT_IDLE_TIMEOUT);
	}

	void svr_getopts(int argc, char ** argv) {

	unsigned int i;
	char ** next = 0;
	int nextisport = 0;
	char* recv_window_arg = NULL;
	char* keepalive_arg = NULL;
	char* idle_timeout_arg = NULL;

	/* see printhelp() for options */
	svr_opts.rsakeyfile = NULL;
	svr_opts.dsskeyfile = NULL;
	svr_opts.bannerfile = NULL;
	svr_opts.banner = NULL;
	svr_opts.forkbg = 1;
	svr_opts.norootlogin = 0;
	svr_opts.noauthpass = 0;
	svr_opts.norootpass = 0;
	svr_opts.allowblankpass = 0;
	svr_opts.inetdmode = 0;
	svr_opts.portcount = 0;
	svr_opts.hostkey = NULL;
	svr_opts.pidfile = DROPBEAR_PIDFILE;
	#ifdef ENABLE_SVR_LOCALTCPFWD
	svr_opts.nolocaltcp = 0;
	#endif
	#ifdef ENABLE_SVR_REMOTETCPFWD
	svr_opts.noremotetcp = 0;
	#endif
	#ifndef DISABLE_ZLIB
	opts.enable_compress = 1;
	#endif
	/* not yet
	opts.ipv4 = 1;
	opts.ipv6 = 1;
	*/
	#ifdef DO_MOTD
	svr_opts.domotd = 1;
	#endif
	#ifndef DISABLE_SYSLOG
	svr_opts.usingsyslog = 1;
	#endif
	opts.recv_window = DEFAULT_RECV_WINDOW;
	opts.keepalive_secs = DEFAULT_KEEPALIVE;
	opts.idle_timeout_secs = DEFAULT_IDLE_TIMEOUT;

	#ifdef ENABLE_SVR_REMOTETCPFWD
	opts.listen_fwd_all = 0;
	#endif

	for (i = 1; i < (unsigned int)argc; i++) {
	if (nextisport) {
	addportandaddress(argv[i]);
	nextisport = 0;
	continue;
	}

	if (next) {
	*next = argv[i];
	if (*next == NULL) {
	dropbear_exit("Invalid null argument");
	}
	next = 0x00;
	continue;
	}

	if (argv[i][0] == '-') {
	switch (argv[i][1]) {
	case 'b':
	next = &svr_opts.bannerfile;
	break;
	#ifdef DROPBEAR_DSS
	case 'd':
	next = &svr_opts.dsskeyfile;
	break;
	#endif
	#ifdef DROPBEAR_RSA
	case 'r':
	next = &svr_opts.rsakeyfile;
	break;
	#endif
	case 'F':
	svr_opts.forkbg = 0;
	break;
	#ifndef DISABLE_SYSLOG
	case 'E':
	svr_opts.usingsyslog = 0;
	break;
	#endif
	#ifdef ENABLE_SVR_LOCALTCPFWD
	case 'j':
	svr_opts.nolocaltcp = 1;
	break;
	#endif
	#ifdef ENABLE_SVR_REMOTETCPFWD
	case 'k':
	svr_opts.noremotetcp = 1;
	break;
	case 'a':
	opts.listen_fwd_all = 1;
	break;
	#endif
	#ifdef INETD_MODE
	case 'i':
	svr_opts.inetdmode = 1;
	break;
	#endif
	case 'p':
	nextisport = 1;
	break;
	case 'P':
	next = &svr_opts.pidfile;
	break;
	#ifdef DO_MOTD
	/* motd is displayed by default, -m turns it off */
	case 'm':
	svr_opts.domotd = 0;
	break;
	#endif
	case 'w':
	svr_opts.norootlogin = 1;
	break;
	case 'W':
	next = &recv_window_arg;
	break;
	case 'K':
	next = &keepalive_arg;
	break;
	case 'I':
	next = &idle_timeout_arg;
	break;
	#if defined(ENABLE_SVR_PASSWORD_AUTH) \|\| defined(ENABLE_SVR_PAM_AUTH)
	case 's':
	svr_opts.noauthpass = 1;
	break;
	case 'g':
	svr_opts.norootpass = 1;
	break;
	case 'B':
	svr_opts.allowblankpass = 1;
	break;
	#endif
	case 'h':
	printhelp(argv[0]);
	exit(EXIT_FAILURE);
	break;
	case 'u':
	/* backwards compatibility with old urandom option */
	break;
	#ifdef DEBUG_TRACE
	case 'v':
	debug_trace = 1;
	break;
	#endif
	default:
	fprintf(stderr, "Unknown argument %s\n", argv[i]);
	printhelp(argv[0]);
	exit(EXIT_FAILURE);
	break;
	}
	}
	}

	/* Set up listening ports */
	if (svr_opts.portcount == 0) {
	svr_opts.ports[0] = m_strdup(DROPBEAR_DEFPORT);
	svr_opts.addresses[0] = m_strdup(DROPBEAR_DEFADDRESS);
	svr_opts.portcount = 1;
	}

	if (svr_opts.dsskeyfile == NULL) {
	svr_opts.dsskeyfile = DSS_PRIV_FILENAME;
	}
	if (svr_opts.rsakeyfile == NULL) {
	svr_opts.rsakeyfile = RSA_PRIV_FILENAME;
	}

	if (svr_opts.bannerfile) {
	struct stat buf;
	if (stat(svr_opts.bannerfile, &buf) != 0) {
	dropbear_exit("Error opening banner file '%s'",
	svr_opts.bannerfile);
	}

	if (buf.st_size > MAX_BANNER_SIZE) {
	dropbear_exit("Banner file too large, max is %d bytes",
	MAX_BANNER_SIZE);
	}

	svr_opts.banner = buf_new(buf.st_size);
	if (buf_readfile(svr_opts.banner, svr_opts.bannerfile)!=DROPBEAR_SUCCESS) {
	dropbear_exit("Error reading banner file '%s'",
	svr_opts.bannerfile);
	}
	buf_setpos(svr_opts.banner, 0);

	}

	if (recv_window_arg) {
	opts.recv_window = atol(recv_window_arg);
	if (opts.recv_window == 0 \|\| opts.recv_window > MAX_RECV_WINDOW) {
	dropbear_exit("Bad recv window '%s'", recv_window_arg);
	}
	}

	if (keepalive_arg) {
	unsigned int val;
	if (m_str_to_uint(keepalive_arg, &val) == DROPBEAR_FAILURE) {
	dropbear_exit("Bad keepalive '%s'", keepalive_arg);
	}
	opts.keepalive_secs = val;
	}

	if (idle_timeout_arg) {
	unsigned int val;
	if (m_str_to_uint(idle_timeout_arg, &val) == DROPBEAR_FAILURE) {
	dropbear_exit("Bad idle_timeout '%s'", idle_timeout_arg);
	}
	opts.idle_timeout_secs = val;
	}
	}

	static void addportandaddress(char* spec) {

	char *myspec = NULL;

	if (svr_opts.portcount < DROPBEAR_MAX_PORTS) {

	/* We don't free it, it becomes part of the runopt state */
	myspec = m_strdup(spec);

	if (myspec[0] == '[') {
	myspec++;
	svr_opts.ports[svr_opts.portcount] = strchr(myspec, ']');
	if (svr_opts.ports[svr_opts.portcount] == NULL) {
	/* Unmatched [ -> exit */
	dropbear_exit("Bad listen address");
	}
	svr_opts.ports[svr_opts.portcount][0] = '\0';
	svr_opts.ports[svr_opts.portcount]++;
	if (svr_opts.ports[svr_opts.portcount][0] != ':') {
	/* Missing port -> exit */
	dropbear_exit("Missing port");
	}
	} else {
	/* search for ':', that separates address and port */
	svr_opts.ports[svr_opts.portcount] = strrchr(myspec, ':');
	}

	if (svr_opts.ports[svr_opts.portcount] == NULL) {
	/* no ':' -> the whole string specifies just a port */
	svr_opts.ports[svr_opts.portcount] = myspec;
	} else {
	/* Split the address/port */
	svr_opts.ports[svr_opts.portcount][0] = '\0';
	svr_opts.ports[svr_opts.portcount]++;
	svr_opts.addresses[svr_opts.portcount] = myspec;
	}

	if (svr_opts.addresses[svr_opts.portcount] == NULL) {
	/* no address given -> fill in the default address */
	svr_opts.addresses[svr_opts.portcount] = m_strdup(DROPBEAR_DEFADDRESS);
	}

	if (svr_opts.ports[svr_opts.portcount][0] == '\0') {
	/* empty port -> exit */
	dropbear_exit("Bad port");
	}

	svr_opts.portcount++;
	}
	}

	static void disablekey(int type, const char* filename) {

	int i;

	for (i = 0; sshhostkey[i].name != NULL; i++) {
	if (sshhostkey[i].val == type) {
	sshhostkey[i].usable = 0;
	break;
	}
	}
	dropbear_log(LOG_WARNING, "Failed reading '%s', disabling %s", filename,
	type == DROPBEAR_SIGNKEY_DSS ? "DSS" : "RSA");
	}

	/* Must be called after syslog/etc is working */
	void loadhostkeys() {

	int ret;
	int type;

	TRACE(("enter loadhostkeys"))

	svr_opts.hostkey = new_sign_key();

	#ifdef DROPBEAR_RSA
	type = DROPBEAR_SIGNKEY_RSA;
	ret = readhostkey(svr_opts.rsakeyfile, svr_opts.hostkey, &type);
	if (ret == DROPBEAR_FAILURE) {
	disablekey(DROPBEAR_SIGNKEY_RSA, svr_opts.rsakeyfile);
	}
	#endif
	#ifdef DROPBEAR_DSS
	type = DROPBEAR_SIGNKEY_DSS;
	ret = readhostkey(svr_opts.dsskeyfile, svr_opts.hostkey, &type);
	if (ret == DROPBEAR_FAILURE) {
	disablekey(DROPBEAR_SIGNKEY_DSS, svr_opts.dsskeyfile);
	}
	#endif

	if ( 1
	#ifdef DROPBEAR_DSS
	&& svr_opts.hostkey->dsskey == NULL
	#endif
	#ifdef DROPBEAR_RSA
	&& svr_opts.hostkey->rsakey == NULL
	#endif
	) {
	dropbear_exit("No hostkeys available");
	}

	TRACE(("leave loadhostkeys"))
	}