enable PAM user switching

[gssapi-openssh.git] / openssh / servconf.c

/* $OpenBSD: servconf.c,v 1.194 2009/01/22 10:02:34 djm Exp $ */
/*
 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
 *                    All rights reserved
 *
 * As far as I am concerned, the code I have written for this software
 * can be used freely for any purpose.  Any derived versions of this
 * software must be clearly marked as such, and if the derived work is
 * incompatible with the protocol description in the RFC file, it must be
 * called by a name other than "ssh" or "Secure Shell".
 */

#include "includes.h"

#include <sys/types.h>
#include <sys/socket.h>

#include <netdb.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <unistd.h>
#include <stdarg.h>
#include <errno.h>

#include "openbsd-compat/sys-queue.h"
#include "xmalloc.h"
#include "ssh.h"
#include "log.h"
#include "buffer.h"
#include "servconf.h"
#include "compat.h"
#include "pathnames.h"
#include "misc.h"
#include "cipher.h"
#include "key.h"
#include "kex.h"
#include "mac.h"
#include "match.h"
#include "channels.h"
#include "groupaccess.h"

static void add_listen_addr(ServerOptions *, char *, int);
static void add_one_listen_addr(ServerOptions *, char *, int);

/* Use of privilege separation or not */
extern int use_privsep;
extern Buffer cfg;

/* Initializes the server options to their default values. */

void
initialize_server_options(ServerOptions *options)
{
	memset(options, 0, sizeof(*options));

	/* Portable-specific options */
	options->use_pam = -1;
	options->permit_pam_user_change = -1;

	/* Standard Options */
	options->num_ports = 0;
	options->ports_from_cmdline = 0;
	options->listen_addrs = NULL;
	options->address_family = -1;
	options->num_host_key_files = 0;
	options->pid_file = NULL;
	options->server_key_bits = -1;
	options->login_grace_time = -1;
	options->key_regeneration_time = -1;
	options->permit_root_login = PERMIT_NOT_SET;
	options->ignore_rhosts = -1;
	options->ignore_user_known_hosts = -1;
	options->print_motd = -1;
	options->print_lastlog = -1;
	options->x11_forwarding = -1;
	options->x11_display_offset = -1;
	options->x11_use_localhost = -1;
	options->xauth_location = NULL;
	options->strict_modes = -1;
	options->tcp_keep_alive = -1;
	options->log_facility = SYSLOG_FACILITY_NOT_SET;
	options->log_level = SYSLOG_LEVEL_NOT_SET;
	options->rhosts_rsa_authentication = -1;
	options->hostbased_authentication = -1;
	options->hostbased_uses_name_from_packet_only = -1;
	options->rsa_authentication = -1;
	options->pubkey_authentication = -1;
	options->kerberos_authentication = -1;
	options->kerberos_or_local_passwd = -1;
	options->kerberos_ticket_cleanup = -1;
#ifdef  SESSION_HOOKS
        options->session_hooks_allow = -1;
        options->session_hooks_startup_cmd = NULL;
        options->session_hooks_shutdown_cmd = NULL;
#endif
	options->kerberos_get_afs_token = -1;
	options->gss_authentication = -1;
	options->gss_deleg_creds = -1;
	options->gss_keyex = -1;
	options->gss_cleanup_creds = -1;
	options->gss_strict_acceptor = -1;
	options->gsi_allow_limited_proxy = -1;
	options->password_authentication = -1;
	options->kbd_interactive_authentication = -1;
	options->challenge_response_authentication = -1;
	options->permit_empty_passwd = -1;
	options->permit_user_env = -1;
	options->use_login = -1;
	options->compression = -1;
	options->allow_tcp_forwarding = -1;
	options->allow_agent_forwarding = -1;
	options->num_allow_users = 0;
	options->num_deny_users = 0;
	options->num_allow_groups = 0;
	options->num_deny_groups = 0;
	options->ciphers = NULL;
	options->macs = NULL;
	options->protocol = SSH_PROTO_UNKNOWN;
	options->gateway_ports = -1;
	options->num_subsystems = 0;
	options->max_startups_begin = -1;
	options->max_startups_rate = -1;
	options->max_startups = -1;
	options->max_authtries = -1;
	options->max_sessions = -1;
	options->banner = NULL;
	options->use_dns = -1;
	options->client_alive_interval = -1;
	options->client_alive_count_max = -1;
	options->authorized_keys_file = NULL;
	options->authorized_keys_file2 = NULL;
	options->num_accept_env = 0;
	options->permit_tun = -1;
	options->num_permitted_opens = -1;
	options->adm_forced_command = NULL;
	options->chroot_directory = NULL;
	options->none_enabled = -1;
	options->tcp_rcv_buf_poll = -1;
	options->hpn_disabled = -1;
	options->hpn_buffer_size = -1;
	options->zero_knowledge_password_authentication = -1;
}

void
fill_default_server_options(ServerOptions *options)
{
	/* needed for hpn socket tests */
	int sock;
	int socksize;
	int socksizelen = sizeof(int);

	/* Portable-specific options */
	if (options->use_pam == -1)
		options->use_pam = 0;
	if (options->permit_pam_user_change == -1)
		options->permit_pam_user_change = 0;

	/* Standard Options */
	if (options->protocol == SSH_PROTO_UNKNOWN)
		options->protocol = SSH_PROTO_1|SSH_PROTO_2;
	if (options->num_host_key_files == 0) {
		/* fill default hostkeys for protocols */
		if (options->protocol & SSH_PROTO_1)
			options->host_key_files[options->num_host_key_files++] =
			    _PATH_HOST_KEY_FILE;
		if (options->protocol & SSH_PROTO_2) {
			options->host_key_files[options->num_host_key_files++] =
			    _PATH_HOST_RSA_KEY_FILE;
			options->host_key_files[options->num_host_key_files++] =
			    _PATH_HOST_DSA_KEY_FILE;
		}
	}
	if (options->num_ports == 0)
		options->ports[options->num_ports++] = SSH_DEFAULT_PORT;
	if (options->listen_addrs == NULL)
		add_listen_addr(options, NULL, 0);
	if (options->pid_file == NULL)
		options->pid_file = _PATH_SSH_DAEMON_PID_FILE;
	if (options->server_key_bits == -1)
		options->server_key_bits = 1024;
	if (options->login_grace_time == -1)
		options->login_grace_time = 120;
	if (options->key_regeneration_time == -1)
		options->key_regeneration_time = 3600;
	if (options->permit_root_login == PERMIT_NOT_SET)
		options->permit_root_login = PERMIT_YES;
	if (options->ignore_rhosts == -1)
		options->ignore_rhosts = 1;
	if (options->ignore_user_known_hosts == -1)
		options->ignore_user_known_hosts = 0;
	if (options->print_motd == -1)
		options->print_motd = 1;
	if (options->print_lastlog == -1)
		options->print_lastlog = 1;
	if (options->x11_forwarding == -1)
		options->x11_forwarding = 0;
	if (options->x11_display_offset == -1)
		options->x11_display_offset = 10;
	if (options->x11_use_localhost == -1)
		options->x11_use_localhost = 1;
	if (options->xauth_location == NULL)
		options->xauth_location = _PATH_XAUTH;
	if (options->strict_modes == -1)
		options->strict_modes = 1;
	if (options->tcp_keep_alive == -1)
		options->tcp_keep_alive = 1;
	if (options->log_facility == SYSLOG_FACILITY_NOT_SET)
		options->log_facility = SYSLOG_FACILITY_AUTH;
	if (options->log_level == SYSLOG_LEVEL_NOT_SET)
		options->log_level = SYSLOG_LEVEL_INFO;
	if (options->rhosts_rsa_authentication == -1)
		options->rhosts_rsa_authentication = 0;
	if (options->hostbased_authentication == -1)
		options->hostbased_authentication = 0;
	if (options->hostbased_uses_name_from_packet_only == -1)
		options->hostbased_uses_name_from_packet_only = 0;
	if (options->rsa_authentication == -1)
		options->rsa_authentication = 1;
	if (options->pubkey_authentication == -1)
		options->pubkey_authentication = 1;
	if (options->kerberos_authentication == -1)
		options->kerberos_authentication = 0;
	if (options->kerberos_or_local_passwd == -1)
		options->kerberos_or_local_passwd = 1;
	if (options->kerberos_ticket_cleanup == -1)
		options->kerberos_ticket_cleanup = 1;
	if (options->kerberos_get_afs_token == -1)
		options->kerberos_get_afs_token = 0;
	if (options->gss_authentication == -1)
		options->gss_authentication = 1;
	if (options->gss_deleg_creds == -1)
		options->gss_deleg_creds = 1;
	if (options->gss_keyex == -1)
		options->gss_keyex = 1;
	if (options->gss_cleanup_creds == -1)
		options->gss_cleanup_creds = 1;
	if (options->gss_strict_acceptor == -1)
		options->gss_strict_acceptor = 1;
	if (options->gsi_allow_limited_proxy == -1)
		options->gsi_allow_limited_proxy = 0;
	if (options->password_authentication == -1)
		options->password_authentication = 1;
	if (options->kbd_interactive_authentication == -1)
		options->kbd_interactive_authentication = 0;
	if (options->challenge_response_authentication == -1)
		options->challenge_response_authentication = 1;
	if (options->permit_empty_passwd == -1)
		options->permit_empty_passwd = 0;
	if (options->permit_user_env == -1)
		options->permit_user_env = 0;
	if (options->use_login == -1)
		options->use_login = 0;
	if (options->compression == -1)
		options->compression = COMP_DELAYED;
	if (options->allow_tcp_forwarding == -1)
		options->allow_tcp_forwarding = 1;
	if (options->allow_agent_forwarding == -1)
		options->allow_agent_forwarding = 1;
	if (options->gateway_ports == -1)
		options->gateway_ports = 0;
	if (options->max_startups == -1)
		options->max_startups = 10;
	if (options->max_startups_rate == -1)
		options->max_startups_rate = 100;		/* 100% */
	if (options->max_startups_begin == -1)
		options->max_startups_begin = options->max_startups;
	if (options->max_authtries == -1)
		options->max_authtries = DEFAULT_AUTH_FAIL_MAX;
	if (options->max_sessions == -1)
		options->max_sessions = DEFAULT_SESSIONS_MAX;
	if (options->use_dns == -1)
		options->use_dns = 1;
	if (options->client_alive_interval == -1)
		options->client_alive_interval = 0;
	if (options->client_alive_count_max == -1)
		options->client_alive_count_max = 3;
	if (options->authorized_keys_file2 == NULL) {
		/* authorized_keys_file2 falls back to authorized_keys_file */
		if (options->authorized_keys_file != NULL)
			options->authorized_keys_file2 = options->authorized_keys_file;
		else
			options->authorized_keys_file2 = _PATH_SSH_USER_PERMITTED_KEYS2;
	}
	if (options->authorized_keys_file == NULL)
		options->authorized_keys_file = _PATH_SSH_USER_PERMITTED_KEYS;
	if (options->permit_tun == -1)
		options->permit_tun = SSH_TUNMODE_NO;
	if (options->zero_knowledge_password_authentication == -1)
		options->zero_knowledge_password_authentication = 0;

	if (options->hpn_disabled == -1) 
		options->hpn_disabled = 0;

	if (options->hpn_buffer_size == -1) {
		/* option not explicitly set. Now we have to figure out */
		/* what value to use */
		if (options->hpn_disabled == 1) {
			options->hpn_buffer_size = CHAN_SES_WINDOW_DEFAULT;
		} else {
			/* get the current RCV size and set it to that */
			/*create a socket but don't connect it */
			/* we use that the get the rcv socket size */
			sock = socket(AF_INET, SOCK_STREAM, 0);
			getsockopt(sock, SOL_SOCKET, SO_RCVBUF, 
				   &socksize, &socksizelen);
			close(sock);
			options->hpn_buffer_size = socksize;
			debug ("HPN Buffer Size: %d", options->hpn_buffer_size);
			
		} 
	} else {
		/* we have to do this incase the user sets both values in a contradictory */
		/* manner. hpn_disabled overrrides hpn_buffer_size*/
		if (options->hpn_disabled <= 0) {
			if (options->hpn_buffer_size == 0)
				options->hpn_buffer_size = 1;
			/* limit the maximum buffer to 64MB */
			if (options->hpn_buffer_size > 64*1024) {
				options->hpn_buffer_size = 64*1024*1024;
			} else {
				options->hpn_buffer_size *= 1024;
			}
		} else
			options->hpn_buffer_size = CHAN_TCP_WINDOW_DEFAULT;
	}

	/* Turn privilege separation on by default */
	if (use_privsep == -1)
		use_privsep = 1;

#ifndef HAVE_MMAP
	if (use_privsep && options->compression == 1) {
		error("This platform does not support both privilege "
		    "separation and compression");
		error("Compression disabled");
		options->compression = 0;
	}
#endif

}

/* Keyword tokens. */
typedef enum {
	sBadOption,		/* == unknown option */
	/* Portable-specific options */
	sUsePAM, sPermitPAMUserChange,
	/* Standard Options */
	sPort, sHostKeyFile, sServerKeyBits, sLoginGraceTime, sKeyRegenerationTime,
	sPermitRootLogin, sLogFacility, sLogLevel,
	sRhostsRSAAuthentication, sRSAAuthentication,
	sKerberosAuthentication, sKerberosOrLocalPasswd, sKerberosTicketCleanup,
	sKerberosGetAFSToken,
	sKerberosTgtPassing, sChallengeResponseAuthentication,
#ifdef SESSION_HOOKS
        sAllowSessionHooks, sSessionHookStartupCmd, sSessionHookShutdownCmd,
#endif
	sPasswordAuthentication, sKbdInteractiveAuthentication,
	sListenAddress, sAddressFamily,
	sPrintMotd, sPrintLastLog, sIgnoreRhosts,
	sX11Forwarding, sX11DisplayOffset, sX11UseLocalhost,
	sStrictModes, sEmptyPasswd, sTCPKeepAlive,
	sPermitUserEnvironment, sUseLogin, sAllowTcpForwarding, sCompression,
	sAllowUsers, sDenyUsers, sAllowGroups, sDenyGroups,
	sIgnoreUserKnownHosts, sCiphers, sMacs, sProtocol, sPidFile,
	sGatewayPorts, sPubkeyAuthentication, sXAuthLocation, sSubsystem,
	sMaxStartups, sMaxAuthTries, sMaxSessions,
	sBanner, sUseDNS, sHostbasedAuthentication,
	sHostbasedUsesNameFromPacketOnly, sClientAliveInterval,
	sClientAliveCountMax, sAuthorizedKeysFile, sAuthorizedKeysFile2,
	sGssAuthentication, sGssCleanupCreds,
    sGssDelegateCreds,
    sGssStrictAcceptor,
	sGssKeyEx, 
    sGssCredsPath,
	sGsiAllowLimitedProxy,
    sAcceptEnv, sPermitTunnel,
	sMatch, sPermitOpen, sForceCommand, sChrootDirectory,
	sUsePrivilegeSeparation, sAllowAgentForwarding,
	sNoneEnabled, sTcpRcvBufPoll, sHPNDisabled, sHPNBufferSize,
	sZeroKnowledgePasswordAuthentication,
	sDeprecated, sUnsupported
} ServerOpCodes;

#define SSHCFG_GLOBAL	0x01	/* allowed in main section of sshd_config */
#define SSHCFG_MATCH	0x02	/* allowed inside a Match section */
#define SSHCFG_ALL	(SSHCFG_GLOBAL|SSHCFG_MATCH)

/* Textual representation of the tokens. */
static struct {
	const char *name;
	ServerOpCodes opcode;
	u_int flags;
} keywords[] = {
	/* Portable-specific options */
#ifdef USE_PAM
	{ "usepam", sUsePAM, SSHCFG_GLOBAL },
	{ "permitpamuserchange", sPermitPAMUserChange, SSHCFG_GLOBAL }
#else
	{ "usepam", sUnsupported, SSHCFG_GLOBAL },
	{ "permitpamuserchange", sUnsupported, SSHCFG_GLOBAL },
#endif
	{ "pamauthenticationviakbdint", sDeprecated, SSHCFG_GLOBAL },
	/* Standard Options */
	{ "port", sPort, SSHCFG_GLOBAL },
	{ "hostkey", sHostKeyFile, SSHCFG_GLOBAL },
	{ "hostdsakey", sHostKeyFile, SSHCFG_GLOBAL },		/* alias */
	{ "pidfile", sPidFile, SSHCFG_GLOBAL },
	{ "serverkeybits", sServerKeyBits, SSHCFG_GLOBAL },
	{ "logingracetime", sLoginGraceTime, SSHCFG_GLOBAL },
	{ "keyregenerationinterval", sKeyRegenerationTime, SSHCFG_GLOBAL },
	{ "permitrootlogin", sPermitRootLogin, SSHCFG_ALL },
	{ "syslogfacility", sLogFacility, SSHCFG_GLOBAL },
	{ "loglevel", sLogLevel, SSHCFG_GLOBAL },
	{ "rhostsauthentication", sDeprecated, SSHCFG_GLOBAL },
	{ "rhostsrsaauthentication", sRhostsRSAAuthentication, SSHCFG_ALL },
	{ "hostbasedauthentication", sHostbasedAuthentication, SSHCFG_ALL },
	{ "hostbasedusesnamefrompacketonly", sHostbasedUsesNameFromPacketOnly, SSHCFG_GLOBAL },
	{ "rsaauthentication", sRSAAuthentication, SSHCFG_ALL },
	{ "pubkeyauthentication", sPubkeyAuthentication, SSHCFG_ALL },
	{ "dsaauthentication", sPubkeyAuthentication, SSHCFG_GLOBAL },	/* alias */
#ifdef KRB5
	{ "kerberosauthentication", sKerberosAuthentication, SSHCFG_ALL },
	{ "kerberosorlocalpasswd", sKerberosOrLocalPasswd, SSHCFG_GLOBAL },
	{ "kerberosticketcleanup", sKerberosTicketCleanup, SSHCFG_GLOBAL },
#ifdef USE_AFS
	{ "kerberosgetafstoken", sKerberosGetAFSToken, SSHCFG_GLOBAL },
#else
	{ "kerberosgetafstoken", sUnsupported, SSHCFG_GLOBAL },
#endif
#else
	{ "kerberosauthentication", sUnsupported, SSHCFG_ALL },
	{ "kerberosorlocalpasswd", sUnsupported, SSHCFG_GLOBAL },
	{ "kerberosticketcleanup", sUnsupported, SSHCFG_GLOBAL },
	{ "kerberosgetafstoken", sUnsupported, SSHCFG_GLOBAL },
#endif
	{ "kerberostgtpassing", sUnsupported, SSHCFG_GLOBAL },
	{ "afstokenpassing", sUnsupported, SSHCFG_GLOBAL },
#ifdef GSSAPI
	{ "gssapiauthentication", sGssAuthentication, SSHCFG_ALL },
	{ "gssapidelegatecredentials", sGssDelegateCreds, SSHCFG_ALL },
	{ "gssapicleanupcredentials", sGssCleanupCreds, SSHCFG_GLOBAL },
	{ "gssapistrictacceptorcheck", sGssStrictAcceptor, SSHCFG_GLOBAL },
	{ "gssapicredentialspath", sGssCredsPath, SSHCFG_GLOBAL },
	{ "gssapikeyexchange", sGssKeyEx, SSHCFG_GLOBAL },
#ifdef GSI
	{ "gsiallowlimitedproxy", sGsiAllowLimitedProxy, SSHCFG_GLOBAL },
#endif
#else
	{ "gssapiauthentication", sUnsupported, SSHCFG_ALL },
	{ "gssapidelegatecredentials", sUnsupported, SSHCFG_ALL },
	{ "gssapicleanupcredentials", sUnsupported, SSHCFG_GLOBAL },
	{ "gssapistrictacceptorcheck", sUnsupported, SSHCFG_GLOBAL },
	{ "gssapicredentialspath", sUnsupported, SSHCFG_GLOBAL },
	{ "gssapikeyexchange", sUnsupported, SSHCFG_GLOBAL },
#ifdef GSI
	{ "gsiallowlimitedproxy", sUnsupported, SSHCFG_GLOBAL },
#endif
#endif
#ifdef SESSION_HOOKS
    { "allowsessionhooks", sAllowSessionHooks, SSHCFG_GLOBAL },
    { "sessionhookstartupcmd", sSessionHookStartupCmd, SSHCFG_GLOBAL },
    { "sessionhookshutdowncmd", sSessionHookShutdownCmd, SSHCFG_GLOBAL },
#endif        
	{ "passwordauthentication", sPasswordAuthentication, SSHCFG_ALL },
	{ "kbdinteractiveauthentication", sKbdInteractiveAuthentication, SSHCFG_ALL },
	{ "challengeresponseauthentication", sChallengeResponseAuthentication, SSHCFG_GLOBAL },
	{ "skeyauthentication", sChallengeResponseAuthentication, SSHCFG_GLOBAL }, /* alias */
#ifdef JPAKE
	{ "zeroknowledgepasswordauthentication", sZeroKnowledgePasswordAuthentication, SSHCFG_ALL },
#else
	{ "zeroknowledgepasswordauthentication", sUnsupported, SSHCFG_ALL },
#endif
	{ "checkmail", sDeprecated, SSHCFG_GLOBAL },
	{ "listenaddress", sListenAddress, SSHCFG_GLOBAL },
	{ "addressfamily", sAddressFamily, SSHCFG_GLOBAL },
	{ "printmotd", sPrintMotd, SSHCFG_GLOBAL },
	{ "printlastlog", sPrintLastLog, SSHCFG_GLOBAL },
	{ "ignorerhosts", sIgnoreRhosts, SSHCFG_GLOBAL },
	{ "ignoreuserknownhosts", sIgnoreUserKnownHosts, SSHCFG_GLOBAL },
	{ "x11forwarding", sX11Forwarding, SSHCFG_ALL },
	{ "x11displayoffset", sX11DisplayOffset, SSHCFG_ALL },
	{ "x11uselocalhost", sX11UseLocalhost, SSHCFG_ALL },
	{ "xauthlocation", sXAuthLocation, SSHCFG_GLOBAL },
	{ "strictmodes", sStrictModes, SSHCFG_GLOBAL },
	{ "permitemptypasswords", sEmptyPasswd, SSHCFG_ALL },
	{ "permituserenvironment", sPermitUserEnvironment, SSHCFG_GLOBAL },
	{ "uselogin", sUseLogin, SSHCFG_GLOBAL },
	{ "compression", sCompression, SSHCFG_GLOBAL },
	{ "tcpkeepalive", sTCPKeepAlive, SSHCFG_GLOBAL },
	{ "keepalive", sTCPKeepAlive, SSHCFG_GLOBAL },	/* obsolete alias */
	{ "allowtcpforwarding", sAllowTcpForwarding, SSHCFG_ALL },
	{ "allowagentforwarding", sAllowAgentForwarding, SSHCFG_ALL },
	{ "allowusers", sAllowUsers, SSHCFG_GLOBAL },
	{ "denyusers", sDenyUsers, SSHCFG_GLOBAL },
	{ "allowgroups", sAllowGroups, SSHCFG_GLOBAL },
	{ "denygroups", sDenyGroups, SSHCFG_GLOBAL },
	{ "ciphers", sCiphers, SSHCFG_GLOBAL },
	{ "macs", sMacs, SSHCFG_GLOBAL },
	{ "protocol", sProtocol, SSHCFG_GLOBAL },
	{ "gatewayports", sGatewayPorts, SSHCFG_ALL },
	{ "subsystem", sSubsystem, SSHCFG_GLOBAL },
	{ "maxstartups", sMaxStartups, SSHCFG_GLOBAL },
	{ "maxauthtries", sMaxAuthTries, SSHCFG_ALL },
	{ "maxsessions", sMaxSessions, SSHCFG_ALL },
	{ "banner", sBanner, SSHCFG_ALL },
	{ "usedns", sUseDNS, SSHCFG_GLOBAL },
	{ "verifyreversemapping", sDeprecated, SSHCFG_GLOBAL },
	{ "reversemappingcheck", sDeprecated, SSHCFG_GLOBAL },
	{ "clientaliveinterval", sClientAliveInterval, SSHCFG_GLOBAL },
	{ "clientalivecountmax", sClientAliveCountMax, SSHCFG_GLOBAL },
	{ "authorizedkeysfile", sAuthorizedKeysFile, SSHCFG_GLOBAL },
	{ "authorizedkeysfile2", sAuthorizedKeysFile2, SSHCFG_GLOBAL },
	{ "useprivilegeseparation", sUsePrivilegeSeparation, SSHCFG_GLOBAL },
	{ "acceptenv", sAcceptEnv, SSHCFG_GLOBAL },
	{ "permittunnel", sPermitTunnel, SSHCFG_GLOBAL },
 	{ "match", sMatch, SSHCFG_ALL },
	{ "permitopen", sPermitOpen, SSHCFG_ALL },
	{ "forcecommand", sForceCommand, SSHCFG_ALL },
	{ "chrootdirectory", sChrootDirectory, SSHCFG_ALL },
	{ "noneenabled", sNoneEnabled },
	{ "hpndisabled", sHPNDisabled },
	{ "hpnbuffersize", sHPNBufferSize },
	{ "tcprcvbufpoll", sTcpRcvBufPoll },
	{ NULL, sBadOption, 0 }
};

static struct {
	int val;
	char *text;
} tunmode_desc[] = {
	{ SSH_TUNMODE_NO, "no" },
	{ SSH_TUNMODE_POINTOPOINT, "point-to-point" },
	{ SSH_TUNMODE_ETHERNET, "ethernet" },
	{ SSH_TUNMODE_YES, "yes" },
	{ -1, NULL }
};

/*
 * Returns the number of the token pointed to by cp or sBadOption.
 */

static ServerOpCodes
parse_token(const char *cp, const char *filename,
	    int linenum, u_int *flags)
{
	u_int i;

	for (i = 0; keywords[i].name; i++)
		if (strcasecmp(cp, keywords[i].name) == 0) {
		        debug ("Config token is %s", keywords[i].name);
			*flags = keywords[i].flags;
			return keywords[i].opcode;
		}

	error("%s: line %d: Bad configuration option: %s",
	    filename, linenum, cp);
	return sBadOption;
}

static void
add_listen_addr(ServerOptions *options, char *addr, int port)
{
	u_int i;

	if (options->num_ports == 0)
		options->ports[options->num_ports++] = SSH_DEFAULT_PORT;
	if (options->address_family == -1)
		options->address_family = AF_UNSPEC;
	if (port == 0)
		for (i = 0; i < options->num_ports; i++)
			add_one_listen_addr(options, addr, options->ports[i]);
	else
		add_one_listen_addr(options, addr, port);
}

static void
add_one_listen_addr(ServerOptions *options, char *addr, int port)
{
	struct addrinfo hints, *ai, *aitop;
	char strport[NI_MAXSERV];
	int gaierr;

	memset(&hints, 0, sizeof(hints));
	hints.ai_family = options->address_family;
	hints.ai_socktype = SOCK_STREAM;
	hints.ai_flags = (addr == NULL) ? AI_PASSIVE : 0;
	snprintf(strport, sizeof strport, "%d", port);
	if ((gaierr = getaddrinfo(addr, strport, &hints, &aitop)) != 0)
		fatal("bad addr or host: %s (%s)",
		    addr ? addr : "<NULL>",
		    ssh_gai_strerror(gaierr));
	for (ai = aitop; ai->ai_next; ai = ai->ai_next)
		;
	ai->ai_next = options->listen_addrs;
	options->listen_addrs = aitop;
}

/*
 * The strategy for the Match blocks is that the config file is parsed twice.
 *
 * The first time is at startup.  activep is initialized to 1 and the
 * directives in the global context are processed and acted on.  Hitting a
 * Match directive unsets activep and the directives inside the block are
 * checked for syntax only.
 *
 * The second time is after a connection has been established but before
 * authentication.  activep is initialized to 2 and global config directives
 * are ignored since they have already been processed.  If the criteria in a
 * Match block is met, activep is set and the subsequent directives
 * processed and actioned until EOF or another Match block unsets it.  Any
 * options set are copied into the main server config.
 *
 * Potential additions/improvements:
 *  - Add Match support for pre-kex directives, eg Protocol, Ciphers.
 *
 *  - Add a Tag directive (idea from David Leonard) ala pf, eg:
 *	Match Address 192.168.0.*
 *		Tag trusted
 *	Match Group wheel
 *		Tag trusted
 *	Match Tag trusted
 *		AllowTcpForwarding yes
 *		GatewayPorts clientspecified
 *		[...]
 *
 *  - Add a PermittedChannelRequests directive
 *	Match Group shell
 *		PermittedChannelRequests session,forwarded-tcpip
 */

static int
match_cfg_line_group(const char *grps, int line, const char *user)
{
	int result = 0;
	struct passwd *pw;

	if (user == NULL)
		goto out;

	if ((pw = getpwnam(user)) == NULL) {
		debug("Can't match group at line %d because user %.100s does "
		    "not exist", line, user);
	} else if (ga_init(pw->pw_name, pw->pw_gid) == 0) {
		debug("Can't Match group because user %.100s not in any group "
		    "at line %d", user, line);
	} else if (ga_match_pattern_list(grps) != 1) {
		debug("user %.100s does not match group list %.100s at line %d",
		    user, grps, line);
	} else {
		debug("user %.100s matched group list %.100s at line %d", user,
		    grps, line);
		result = 1;
	}
out:
	ga_free();
	return result;
}

static int
match_cfg_line(char **condition, int line, const char *user, const char *host,
    const char *address)
{
	int result = 1;
	char *arg, *attrib, *cp = *condition;
	size_t len;

	if (user == NULL)
		debug3("checking syntax for 'Match %s'", cp);
	else
		debug3("checking match for '%s' user %s host %s addr %s", cp,
		    user ? user : "(null)", host ? host : "(null)",
		    address ? address : "(null)");

	while ((attrib = strdelim(&cp)) && *attrib != '\0') {
		if ((arg = strdelim(&cp)) == NULL || *arg == '\0') {
			error("Missing Match criteria for %s", attrib);
			return -1;
		}
		len = strlen(arg);
		if (strcasecmp(attrib, "user") == 0) {
			if (!user) {
				result = 0;
				continue;
			}
			if (match_pattern_list(user, arg, len, 0) != 1)
				result = 0;
			else
				debug("user %.100s matched 'User %.100s' at "
				    "line %d", user, arg, line);
		} else if (strcasecmp(attrib, "group") == 0) {
			switch (match_cfg_line_group(arg, line, user)) {
			case -1:
				return -1;
			case 0:
				result = 0;
			}
		} else if (strcasecmp(attrib, "host") == 0) {
			if (!host) {
				result = 0;
				continue;
			}
			if (match_hostname(host, arg, len) != 1)
				result = 0;
			else
				debug("connection from %.100s matched 'Host "
				    "%.100s' at line %d", host, arg, line);
		} else if (strcasecmp(attrib, "address") == 0) {
			switch (addr_match_list(address, arg)) {
			case 1:
				debug("connection from %.100s matched 'Address "
				    "%.100s' at line %d", address, arg, line);
				break;
			case 0:
			case -1:
				result = 0;
				break;
			case -2:
				return -1;
			}
		} else {
			error("Unsupported Match attribute %s", attrib);
			return -1;
		}
	}
	if (user != NULL)
		debug3("match %sfound", result ? "" : "not ");
	*condition = cp;
	return result;
}

#define WHITESPACE " \t\r\n"

int
process_server_config_line(ServerOptions *options, char *line,
    const char *filename, int linenum, int *activep, const char *user,
    const char *host, const char *address)
{
	char *cp, **charptr, *arg, *p;
	int cmdline = 0, *intptr, value, n;
	SyslogFacility *log_facility_ptr;
	LogLevel *log_level_ptr;
	ServerOpCodes opcode;
	int port;
	u_int i, flags = 0;
	size_t len;

	cp = line;
	if ((arg = strdelim(&cp)) == NULL)
		return 0;
	/* Ignore leading whitespace */
	if (*arg == '\0')
		arg = strdelim(&cp);
	if (!arg || !*arg || *arg == '#')
		return 0;
	intptr = NULL;
	charptr = NULL;
	opcode = parse_token(arg, filename, linenum, &flags);

	if (activep == NULL) { /* We are processing a command line directive */
		cmdline = 1;
		activep = &cmdline;
	}
	if (*activep && opcode != sMatch)
		debug3("%s:%d setting %s %s", filename, linenum, arg, cp);
	if (*activep == 0 && !(flags & SSHCFG_MATCH)) {
		if (user == NULL) {
			fatal("%s line %d: Directive '%s' is not allowed "
			    "within a Match block", filename, linenum, arg);
		} else { /* this is a directive we have already processed */
			while (arg)
				arg = strdelim(&cp);
			return 0;
		}
	}

	switch (opcode) {
	/* Portable-specific options */
	case sUsePAM:
		intptr = &options->use_pam;
		goto parse_flag;

	case sPermitPAMUserChange:
		intptr = &options->permit_pam_user_change;
		goto parse_flag;

	/* Standard Options */
	case sBadOption:
		return -1;
	case sPort:
		/* ignore ports from configfile if cmdline specifies ports */
		if (options->ports_from_cmdline)
			return 0;
		if (options->listen_addrs != NULL)
			fatal("%s line %d: ports must be specified before "
			    "ListenAddress.", filename, linenum);
		if (options->num_ports >= MAX_PORTS)
			fatal("%s line %d: too many ports.",
			    filename, linenum);
		arg = strdelim(&cp);
		if (!arg || *arg == '\0')
			fatal("%s line %d: missing port number.",
			    filename, linenum);
		options->ports[options->num_ports++] = a2port(arg);
		if (options->ports[options->num_ports-1] <= 0)
			fatal("%s line %d: Badly formatted port number.",
			    filename, linenum);
		break;

	case sServerKeyBits:
		intptr = &options->server_key_bits;
 parse_int:
		arg = strdelim(&cp);
		if (!arg || *arg == '\0')
			fatal("%s line %d: missing integer value.",
			    filename, linenum);
		value = atoi(arg);
		if (*activep && *intptr == -1)
			*intptr = value;
		break;

	case sLoginGraceTime:
		intptr = &options->login_grace_time;
 parse_time:
		arg = strdelim(&cp);
		if (!arg || *arg == '\0')
			fatal("%s line %d: missing time value.",
			    filename, linenum);
		if ((value = convtime(arg)) == -1)
			fatal("%s line %d: invalid time value.",
			    filename, linenum);
		if (*intptr == -1)
			*intptr = value;
		break;

	case sKeyRegenerationTime:
		intptr = &options->key_regeneration_time;
		goto parse_time;

	case sListenAddress:
		arg = strdelim(&cp);
		if (arg == NULL || *arg == '\0')
			fatal("%s line %d: missing address",
			    filename, linenum);
		/* check for bare IPv6 address: no "[]" and 2 or more ":" */
		if (strchr(arg, '[') == NULL && (p = strchr(arg, ':')) != NULL
		    && strchr(p+1, ':') != NULL) {
			add_listen_addr(options, arg, 0);
			break;
		}
		p = hpdelim(&arg);
		if (p == NULL)
			fatal("%s line %d: bad address:port usage",
			    filename, linenum);
		p = cleanhostname(p);
		if (arg == NULL)
			port = 0;
		else if ((port = a2port(arg)) <= 0)
			fatal("%s line %d: bad port number", filename, linenum);

		add_listen_addr(options, p, port);

		break;

	case sAddressFamily:
		arg = strdelim(&cp);
		if (!arg || *arg == '\0')
			fatal("%s line %d: missing address family.",
			    filename, linenum);
		intptr = &options->address_family;
		if (options->listen_addrs != NULL)
			fatal("%s line %d: address family must be specified before "
			    "ListenAddress.", filename, linenum);
		if (strcasecmp(arg, "inet") == 0)
			value = AF_INET;
		else if (strcasecmp(arg, "inet6") == 0)
			value = AF_INET6;
		else if (strcasecmp(arg, "any") == 0)
			value = AF_UNSPEC;
		else
			fatal("%s line %d: unsupported address family \"%s\".",
			    filename, linenum, arg);
		if (*intptr == -1)
			*intptr = value;
		break;

	case sHostKeyFile:
		intptr = &options->num_host_key_files;
		if (*intptr >= MAX_HOSTKEYS)
			fatal("%s line %d: too many host keys specified (max %d).",
			    filename, linenum, MAX_HOSTKEYS);
		charptr = &options->host_key_files[*intptr];
 parse_filename:
		arg = strdelim(&cp);
		if (!arg || *arg == '\0')
			fatal("%s line %d: missing file name.",
			    filename, linenum);
		if (*activep && *charptr == NULL) {
			*charptr = tilde_expand_filename(arg, getuid());
			/* increase optional counter */
			if (intptr != NULL)
				*intptr = *intptr + 1;
		}
		break;

	case sPidFile:
		charptr = &options->pid_file;
		goto parse_filename;

	case sPermitRootLogin:
		intptr = &options->permit_root_login;
		arg = strdelim(&cp);
		if (!arg || *arg == '\0')
			fatal("%s line %d: missing yes/"
			    "without-password/forced-commands-only/no "
			    "argument.", filename, linenum);
		value = 0;	/* silence compiler */
		if (strcmp(arg, "without-password") == 0)
			value = PERMIT_NO_PASSWD;
		else if (strcmp(arg, "forced-commands-only") == 0)
			value = PERMIT_FORCED_ONLY;
		else if (strcmp(arg, "yes") == 0)
			value = PERMIT_YES;
		else if (strcmp(arg, "no") == 0)
			value = PERMIT_NO;
		else
			fatal("%s line %d: Bad yes/"
			    "without-password/forced-commands-only/no "
			    "argument: %s", filename, linenum, arg);
		if (*activep && *intptr == -1)
			*intptr = value;
		break;

	case sIgnoreRhosts:
		intptr = &options->ignore_rhosts;
 parse_flag:
		arg = strdelim(&cp);
		if (!arg || *arg == '\0')
			fatal("%s line %d: missing yes/no argument.",
			    filename, linenum);
		value = 0;	/* silence compiler */
		if (strcmp(arg, "yes") == 0)
			value = 1;
		else if (strcmp(arg, "no") == 0)
			value = 0;
		else
			fatal("%s line %d: Bad yes/no argument: %s",
				filename, linenum, arg);
		if (*activep && *intptr == -1)
			*intptr = value;
		break;

	case sNoneEnabled:
		intptr = &options->none_enabled;
		goto parse_flag;

	case sTcpRcvBufPoll:
		intptr = &options->tcp_rcv_buf_poll;
		goto parse_flag;

	case sHPNDisabled:
		intptr = &options->hpn_disabled;
		goto parse_flag;

	case sHPNBufferSize:
		intptr = &options->hpn_buffer_size;
		goto parse_int;

	case sIgnoreUserKnownHosts:
		intptr = &options->ignore_user_known_hosts;
		goto parse_flag;

	case sRhostsRSAAuthentication:
		intptr = &options->rhosts_rsa_authentication;
		goto parse_flag;

	case sHostbasedAuthentication:
		intptr = &options->hostbased_authentication;
		goto parse_flag;

	case sHostbasedUsesNameFromPacketOnly:
		intptr = &options->hostbased_uses_name_from_packet_only;
		goto parse_flag;

	case sRSAAuthentication:
		intptr = &options->rsa_authentication;
		goto parse_flag;

	case sPubkeyAuthentication:
		intptr = &options->pubkey_authentication;
		goto parse_flag;

	case sKerberosAuthentication:
		intptr = &options->kerberos_authentication;
		goto parse_flag;

	case sKerberosOrLocalPasswd:
		intptr = &options->kerberos_or_local_passwd;
		goto parse_flag;

	case sKerberosTicketCleanup:
		intptr = &options->kerberos_ticket_cleanup;
		goto parse_flag;

	case sKerberosGetAFSToken:
		intptr = &options->kerberos_get_afs_token;
		goto parse_flag;

	case sGssAuthentication:
		intptr = &options->gss_authentication;
		goto parse_flag;

	case sGssDelegateCreds:
		intptr = &options->gss_deleg_creds;
		goto parse_flag;

	case sGssKeyEx:
		intptr = &options->gss_keyex;
		goto parse_flag;

	case sGssCleanupCreds:
		intptr = &options->gss_cleanup_creds;
		goto parse_flag;

	case sGssStrictAcceptor:
		intptr = &options->gss_strict_acceptor;
		goto parse_flag;

	case sGssCredsPath:
		charptr = &options->gss_creds_path;
		goto parse_filename;

	case sGsiAllowLimitedProxy:
		intptr = &options->gsi_allow_limited_proxy;
		goto parse_flag;

#ifdef SESSION_HOOKS
        case sAllowSessionHooks:
                intptr = &options->session_hooks_allow;
                goto parse_flag;
        case sSessionHookStartupCmd:
        case sSessionHookShutdownCmd:
                arg = strdelim(&cp);
                if (!arg || *arg == '\0')
                    fatal("%s line %d: empty session hook command",
                          filename, linenum);
                if (opcode==sSessionHookStartupCmd)
                    options->session_hooks_startup_cmd = strdup(arg);
                else
                    options->session_hooks_shutdown_cmd = strdup(arg);
                break;
#endif                  

	case sPasswordAuthentication:
		intptr = &options->password_authentication;
		goto parse_flag;

	case sZeroKnowledgePasswordAuthentication:
		intptr = &options->zero_knowledge_password_authentication;
		goto parse_flag;

	case sKbdInteractiveAuthentication:
		intptr = &options->kbd_interactive_authentication;
		goto parse_flag;

	case sChallengeResponseAuthentication:
		intptr = &options->challenge_response_authentication;
		goto parse_flag;

	case sPrintMotd:
		intptr = &options->print_motd;
		goto parse_flag;

	case sPrintLastLog:
		intptr = &options->print_lastlog;
		goto parse_flag;

	case sX11Forwarding:
		intptr = &options->x11_forwarding;
		goto parse_flag;

	case sX11DisplayOffset:
		intptr = &options->x11_display_offset;
		goto parse_int;

	case sX11UseLocalhost:
		intptr = &options->x11_use_localhost;
		goto parse_flag;

	case sXAuthLocation:
		charptr = &options->xauth_location;
		goto parse_filename;

	case sStrictModes:
		intptr = &options->strict_modes;
		goto parse_flag;

	case sTCPKeepAlive:
		intptr = &options->tcp_keep_alive;
		goto parse_flag;

	case sEmptyPasswd:
		intptr = &options->permit_empty_passwd;
		goto parse_flag;

	case sPermitUserEnvironment:
		intptr = &options->permit_user_env;
		goto parse_flag;

	case sUseLogin:
		intptr = &options->use_login;
		goto parse_flag;

	case sCompression:
		intptr = &options->compression;
		arg = strdelim(&cp);
		if (!arg || *arg == '\0')
			fatal("%s line %d: missing yes/no/delayed "
			    "argument.", filename, linenum);
		value = 0;	/* silence compiler */
		if (strcmp(arg, "delayed") == 0)
			value = COMP_DELAYED;
		else if (strcmp(arg, "yes") == 0)
			value = COMP_ZLIB;
		else if (strcmp(arg, "no") == 0)
			value = COMP_NONE;
		else
			fatal("%s line %d: Bad yes/no/delayed "
			    "argument: %s", filename, linenum, arg);
		if (*intptr == -1)
			*intptr = value;
		break;

	case sGatewayPorts:
		intptr = &options->gateway_ports;
		arg = strdelim(&cp);
		if (!arg || *arg == '\0')
			fatal("%s line %d: missing yes/no/clientspecified "
			    "argument.", filename, linenum);
		value = 0;	/* silence compiler */
		if (strcmp(arg, "clientspecified") == 0)
			value = 2;
		else if (strcmp(arg, "yes") == 0)
			value = 1;
		else if (strcmp(arg, "no") == 0)
			value = 0;
		else
			fatal("%s line %d: Bad yes/no/clientspecified "
			    "argument: %s", filename, linenum, arg);
		if (*activep && *intptr == -1)
			*intptr = value;
		break;

	case sUseDNS:
		intptr = &options->use_dns;
		goto parse_flag;

	case sLogFacility:
		log_facility_ptr = &options->log_facility;
		arg = strdelim(&cp);
		value = log_facility_number(arg);
		if (value == SYSLOG_FACILITY_NOT_SET)
			fatal("%.200s line %d: unsupported log facility '%s'",
			    filename, linenum, arg ? arg : "<NONE>");
		if (*log_facility_ptr == -1)
			*log_facility_ptr = (SyslogFacility) value;
		break;

	case sLogLevel:
		log_level_ptr = &options->log_level;
		arg = strdelim(&cp);
		value = log_level_number(arg);
		if (value == SYSLOG_LEVEL_NOT_SET)
			fatal("%.200s line %d: unsupported log level '%s'",
			    filename, linenum, arg ? arg : "<NONE>");
		if (*log_level_ptr == -1)
			*log_level_ptr = (LogLevel) value;
		break;

	case sAllowTcpForwarding:
		intptr = &options->allow_tcp_forwarding;
		goto parse_flag;

	case sAllowAgentForwarding:
		intptr = &options->allow_agent_forwarding;
		goto parse_flag;

	case sUsePrivilegeSeparation:
		intptr = &use_privsep;
		goto parse_flag;

	case sAllowUsers:
		while ((arg = strdelim(&cp)) && *arg != '\0') {
			if (options->num_allow_users >= MAX_ALLOW_USERS)
				fatal("%s line %d: too many allow users.",
				    filename, linenum);
			options->allow_users[options->num_allow_users++] =
			    xstrdup(arg);
		}
		break;

	case sDenyUsers:
		while ((arg = strdelim(&cp)) && *arg != '\0') {
			if (options->num_deny_users >= MAX_DENY_USERS)
				fatal("%s line %d: too many deny users.",
				    filename, linenum);
			options->deny_users[options->num_deny_users++] =
			    xstrdup(arg);
		}
		break;

	case sAllowGroups:
		while ((arg = strdelim(&cp)) && *arg != '\0') {
			if (options->num_allow_groups >= MAX_ALLOW_GROUPS)
				fatal("%s line %d: too many allow groups.",
				    filename, linenum);
			options->allow_groups[options->num_allow_groups++] =
			    xstrdup(arg);
		}
		break;

	case sDenyGroups:
		while ((arg = strdelim(&cp)) && *arg != '\0') {
			if (options->num_deny_groups >= MAX_DENY_GROUPS)
				fatal("%s line %d: too many deny groups.",
				    filename, linenum);
			options->deny_groups[options->num_deny_groups++] = xstrdup(arg);
		}
		break;

	case sCiphers:
		arg = strdelim(&cp);
		if (!arg || *arg == '\0')
			fatal("%s line %d: Missing argument.", filename, linenum);
		if (!ciphers_valid(arg))
			fatal("%s line %d: Bad SSH2 cipher spec '%s'.",
			    filename, linenum, arg ? arg : "<NONE>");
		if (options->ciphers == NULL)
			options->ciphers = xstrdup(arg);
		break;

	case sMacs:
		arg = strdelim(&cp);
		if (!arg || *arg == '\0')
			fatal("%s line %d: Missing argument.", filename, linenum);
		if (!mac_valid(arg))
			fatal("%s line %d: Bad SSH2 mac spec '%s'.",
			    filename, linenum, arg ? arg : "<NONE>");
		if (options->macs == NULL)
			options->macs = xstrdup(arg);
		break;

	case sProtocol:
		intptr = &options->protocol;
		arg = strdelim(&cp);
		if (!arg || *arg == '\0')
			fatal("%s line %d: Missing argument.", filename, linenum);
		value = proto_spec(arg);
		if (value == SSH_PROTO_UNKNOWN)
			fatal("%s line %d: Bad protocol spec '%s'.",
			    filename, linenum, arg ? arg : "<NONE>");
		if (*intptr == SSH_PROTO_UNKNOWN)
			*intptr = value;
		break;

	case sSubsystem:
		if (options->num_subsystems >= MAX_SUBSYSTEMS) {
			fatal("%s line %d: too many subsystems defined.",
			    filename, linenum);
		}
		arg = strdelim(&cp);
		if (!arg || *arg == '\0')
			fatal("%s line %d: Missing subsystem name.",
			    filename, linenum);
		if (!*activep) {
			arg = strdelim(&cp);
			break;
		}
		for (i = 0; i < options->num_subsystems; i++)
			if (strcmp(arg, options->subsystem_name[i]) == 0)
				fatal("%s line %d: Subsystem '%s' already defined.",
				    filename, linenum, arg);
		options->subsystem_name[options->num_subsystems] = xstrdup(arg);
		arg = strdelim(&cp);
		if (!arg || *arg == '\0')
			fatal("%s line %d: Missing subsystem command.",
			    filename, linenum);
		options->subsystem_command[options->num_subsystems] = xstrdup(arg);

		/* Collect arguments (separate to executable) */
		p = xstrdup(arg);
		len = strlen(p) + 1;
		while ((arg = strdelim(&cp)) != NULL && *arg != '\0') {
			len += 1 + strlen(arg);
			p = xrealloc(p, 1, len);
			strlcat(p, " ", len);
			strlcat(p, arg, len);
		}
		options->subsystem_args[options->num_subsystems] = p;
		options->num_subsystems++;
		break;

	case sMaxStartups:
		arg = strdelim(&cp);
		if (!arg || *arg == '\0')
			fatal("%s line %d: Missing MaxStartups spec.",
			    filename, linenum);
		if ((n = sscanf(arg, "%d:%d:%d",
		    &options->max_startups_begin,
		    &options->max_startups_rate,
		    &options->max_startups)) == 3) {
			if (options->max_startups_begin >
			    options->max_startups ||
			    options->max_startups_rate > 100 ||
			    options->max_startups_rate < 1)
				fatal("%s line %d: Illegal MaxStartups spec.",
				    filename, linenum);
		} else if (n != 1)
			fatal("%s line %d: Illegal MaxStartups spec.",
			    filename, linenum);
		else
			options->max_startups = options->max_startups_begin;
		break;

	case sMaxAuthTries:
		intptr = &options->max_authtries;
		goto parse_int;

	case sMaxSessions:
		intptr = &options->max_sessions;
		goto parse_int;

	case sBanner:
		charptr = &options->banner;
		goto parse_filename;

	/*
	 * These options can contain %X options expanded at
	 * connect time, so that you can specify paths like:
	 *
	 * AuthorizedKeysFile	/etc/ssh_keys/%u
	 */
	case sAuthorizedKeysFile:
	case sAuthorizedKeysFile2:
		charptr = (opcode == sAuthorizedKeysFile) ?
		    &options->authorized_keys_file :
		    &options->authorized_keys_file2;
		goto parse_filename;

	case sClientAliveInterval:
		intptr = &options->client_alive_interval;
		goto parse_time;

	case sClientAliveCountMax:
		intptr = &options->client_alive_count_max;
		goto parse_int;

	case sAcceptEnv:
		while ((arg = strdelim(&cp)) && *arg != '\0') {
			if (strchr(arg, '=') != NULL)
				fatal("%s line %d: Invalid environment name.",
				    filename, linenum);
			if (options->num_accept_env >= MAX_ACCEPT_ENV)
				fatal("%s line %d: too many allow env.",
				    filename, linenum);
			if (!*activep)
				break;
			options->accept_env[options->num_accept_env++] =
			    xstrdup(arg);
		}
		break;

	case sPermitTunnel:
		intptr = &options->permit_tun;
		arg = strdelim(&cp);
		if (!arg || *arg == '\0')
			fatal("%s line %d: Missing yes/point-to-point/"
			    "ethernet/no argument.", filename, linenum);
		value = -1;
		for (i = 0; tunmode_desc[i].val != -1; i++)
			if (strcmp(tunmode_desc[i].text, arg) == 0) {
				value = tunmode_desc[i].val;
				break;
			}
		if (value == -1)
			fatal("%s line %d: Bad yes/point-to-point/ethernet/"
			    "no argument: %s", filename, linenum, arg);
		if (*intptr == -1)
			*intptr = value;
		break;

	case sMatch:
		if (cmdline)
			fatal("Match directive not supported as a command-line "
			   "option");
		value = match_cfg_line(&cp, linenum, user, host, address);
		if (value < 0)
			fatal("%s line %d: Bad Match condition", filename,
			    linenum);
		*activep = value;
		break;

	case sPermitOpen:
		arg = strdelim(&cp);
		if (!arg || *arg == '\0')
			fatal("%s line %d: missing PermitOpen specification",
			    filename, linenum);
		n = options->num_permitted_opens;	/* modified later */
		if (strcmp(arg, "any") == 0) {
			if (*activep && n == -1) {
				channel_clear_adm_permitted_opens();
				options->num_permitted_opens = 0;
			}
			break;
		}
		if (*activep && n == -1)
			channel_clear_adm_permitted_opens();
		for (; arg != NULL && *arg != '\0'; arg = strdelim(&cp)) {
			p = hpdelim(&arg);
			if (p == NULL)
				fatal("%s line %d: missing host in PermitOpen",
				    filename, linenum);
			p = cleanhostname(p);
			if (arg == NULL || (port = a2port(arg)) <= 0)
				fatal("%s line %d: bad port number in "
				    "PermitOpen", filename, linenum);
			if (*activep && n == -1)
				options->num_permitted_opens =
				    channel_add_adm_permitted_opens(p, port);
		}
		break;

	case sForceCommand:
		if (cp == NULL)
			fatal("%.200s line %d: Missing argument.", filename,
			    linenum);
		len = strspn(cp, WHITESPACE);
		if (*activep && options->adm_forced_command == NULL)
			options->adm_forced_command = xstrdup(cp + len);
		return 0;

	case sChrootDirectory:
		charptr = &options->chroot_directory;

		arg = strdelim(&cp);
		if (!arg || *arg == '\0')
			fatal("%s line %d: missing file name.",
			    filename, linenum);
		if (*activep && *charptr == NULL)
			*charptr = xstrdup(arg);
		break;

	case sDeprecated:
		logit("%s line %d: Deprecated option %s",
		    filename, linenum, arg);
		while (arg)
		    arg = strdelim(&cp);
		break;

	case sUnsupported:
		logit("%s line %d: Unsupported option %s",
		    filename, linenum, arg);
		while (arg)
		    arg = strdelim(&cp);
		break;

	default:
		fatal("%s line %d: Missing handler for opcode %s (%d)",
		    filename, linenum, arg, opcode);
	}
	if ((arg = strdelim(&cp)) != NULL && *arg != '\0')
		fatal("%s line %d: garbage at end of line; \"%.200s\".",
		    filename, linenum, arg);
	return 0;
}

/* Reads the server configuration file. */

void
load_server_config(const char *filename, Buffer *conf)
{
	char line[1024], *cp;
	FILE *f;

	debug2("%s: filename %s", __func__, filename);
	if ((f = fopen(filename, "r")) == NULL) {
		perror(filename);
		exit(1);
	}
	buffer_clear(conf);
	while (fgets(line, sizeof(line), f)) {
		/*
		 * Trim out comments and strip whitespace
		 * NB - preserve newlines, they are needed to reproduce
		 * line numbers later for error messages
		 */
		if ((cp = strchr(line, '#')) != NULL)
			memcpy(cp, "\n", 2);
		cp = line + strspn(line, " \t\r");

		buffer_append(conf, cp, strlen(cp));
	}
	buffer_append(conf, "\0", 1);
	fclose(f);
	debug2("%s: done config len = %d", __func__, buffer_len(conf));
}

void
parse_server_match_config(ServerOptions *options, const char *user,
    const char *host, const char *address)
{
	ServerOptions mo;

	initialize_server_options(&mo);
	parse_server_config(&mo, "reprocess config", &cfg, user, host, address);
	copy_set_server_options(options, &mo, 0);
}

/* Helper macros */
#define M_CP_INTOPT(n) do {\
	if (src->n != -1) \
		dst->n = src->n; \
} while (0)
#define M_CP_STROPT(n) do {\
	if (src->n != NULL) { \
		if (dst->n != NULL) \
			xfree(dst->n); \
		dst->n = src->n; \
	} \
} while(0)

/*
 * Copy any supported values that are set.
 *
 * If the preauth flag is set, we do not bother copying the the string or
 * array values that are not used pre-authentication, because any that we
 * do use must be explictly sent in mm_getpwnamallow().
 */
void
copy_set_server_options(ServerOptions *dst, ServerOptions *src, int preauth)
{
	M_CP_INTOPT(password_authentication);
	M_CP_INTOPT(gss_authentication);
	M_CP_INTOPT(gss_deleg_creds);
	M_CP_INTOPT(rsa_authentication);
	M_CP_INTOPT(pubkey_authentication);
	M_CP_INTOPT(kerberos_authentication);
	M_CP_INTOPT(hostbased_authentication);
	M_CP_INTOPT(kbd_interactive_authentication);
	M_CP_INTOPT(zero_knowledge_password_authentication);
	M_CP_INTOPT(permit_root_login);
	M_CP_INTOPT(permit_empty_passwd);

	M_CP_INTOPT(allow_tcp_forwarding);
	M_CP_INTOPT(allow_agent_forwarding);
	M_CP_INTOPT(gateway_ports);
	M_CP_INTOPT(x11_display_offset);
	M_CP_INTOPT(x11_forwarding);
	M_CP_INTOPT(x11_use_localhost);
	M_CP_INTOPT(max_sessions);
	M_CP_INTOPT(max_authtries);

	M_CP_STROPT(banner);
	if (preauth)
		return;
	M_CP_STROPT(adm_forced_command);
	M_CP_STROPT(chroot_directory);
}

#undef M_CP_INTOPT
#undef M_CP_STROPT

void
parse_server_config(ServerOptions *options, const char *filename, Buffer *conf,
    const char *user, const char *host, const char *address)
{
	int active, linenum, bad_options = 0;
	char *cp, *obuf, *cbuf;

	debug2("%s: config %s len %d", __func__, filename, buffer_len(conf));

	obuf = cbuf = xstrdup(buffer_ptr(conf));
	active = user ? 0 : 1;
	linenum = 1;
	while ((cp = strsep(&cbuf, "\n")) != NULL) {
		if (process_server_config_line(options, cp, filename,
		    linenum++, &active, user, host, address) != 0)
			bad_options++;
	}
	xfree(obuf);
	if (bad_options > 0)
		fatal("%s: terminating, %d bad configuration options",
		    filename, bad_options);
}

static const char *
fmt_intarg(ServerOpCodes code, int val)
{
	if (code == sAddressFamily) {
		switch (val) {
		case AF_INET:
			return "inet";
		case AF_INET6:
			return "inet6";
		case AF_UNSPEC:
			return "any";
		default:
			return "UNKNOWN";
		}
	}
	if (code == sPermitRootLogin) {
		switch (val) {
		case PERMIT_NO_PASSWD:
			return "without-password";
		case PERMIT_FORCED_ONLY:
			return "forced-commands-only";
		case PERMIT_YES:
			return "yes";
		}
	}
	if (code == sProtocol) {
		switch (val) {
		case SSH_PROTO_1:
			return "1";
		case SSH_PROTO_2:
			return "2";
		case (SSH_PROTO_1|SSH_PROTO_2):
			return "2,1";
		default:
			return "UNKNOWN";
		}
	}
	if (code == sGatewayPorts && val == 2)
		return "clientspecified";
	if (code == sCompression && val == COMP_DELAYED)
		return "delayed";
	switch (val) {
	case -1:
		return "unset";
	case 0:
		return "no";
	case 1:
		return "yes";
	}
	return "UNKNOWN";
}

static const char *
lookup_opcode_name(ServerOpCodes code)
{
	u_int i;

	for (i = 0; keywords[i].name != NULL; i++)
		if (keywords[i].opcode == code)
			return(keywords[i].name);
	return "UNKNOWN";
}

static void
dump_cfg_int(ServerOpCodes code, int val)
{
	printf("%s %d\n", lookup_opcode_name(code), val);
}

static void
dump_cfg_fmtint(ServerOpCodes code, int val)
{
	printf("%s %s\n", lookup_opcode_name(code), fmt_intarg(code, val));
}

static void
dump_cfg_string(ServerOpCodes code, const char *val)
{
	if (val == NULL)
		return;
	printf("%s %s\n", lookup_opcode_name(code), val);
}

static void
dump_cfg_strarray(ServerOpCodes code, u_int count, char **vals)
{
	u_int i;

	for (i = 0; i < count; i++)
		printf("%s %s\n", lookup_opcode_name(code),  vals[i]);
}

void
dump_config(ServerOptions *o)
{
	u_int i;
	int ret;
	struct addrinfo *ai;
	char addr[NI_MAXHOST], port[NI_MAXSERV], *s = NULL;

	/* these are usually at the top of the config */
	for (i = 0; i < o->num_ports; i++)
		printf("port %d\n", o->ports[i]);
	dump_cfg_fmtint(sProtocol, o->protocol);
	dump_cfg_fmtint(sAddressFamily, o->address_family);

	/* ListenAddress must be after Port */
	for (ai = o->listen_addrs; ai; ai = ai->ai_next) {
		if ((ret = getnameinfo(ai->ai_addr, ai->ai_addrlen, addr,
		    sizeof(addr), port, sizeof(port),
		    NI_NUMERICHOST|NI_NUMERICSERV)) != 0) {
			error("getnameinfo failed: %.100s",
			    (ret != EAI_SYSTEM) ? gai_strerror(ret) :
			    strerror(errno));
		} else {
			if (ai->ai_family == AF_INET6)
				printf("listenaddress [%s]:%s\n", addr, port);
			else
				printf("listenaddress %s:%s\n", addr, port);
		}
	}

	/* integer arguments */
#ifdef USE_PAM
	dump_cfg_int(sUsePAM, o->use_pam);
#endif
	dump_cfg_int(sServerKeyBits, o->server_key_bits);
	dump_cfg_int(sLoginGraceTime, o->login_grace_time);
	dump_cfg_int(sKeyRegenerationTime, o->key_regeneration_time);
	dump_cfg_int(sX11DisplayOffset, o->x11_display_offset);
	dump_cfg_int(sMaxAuthTries, o->max_authtries);
	dump_cfg_int(sMaxSessions, o->max_sessions);
	dump_cfg_int(sClientAliveInterval, o->client_alive_interval);
	dump_cfg_int(sClientAliveCountMax, o->client_alive_count_max);

	/* formatted integer arguments */
	dump_cfg_fmtint(sPermitRootLogin, o->permit_root_login);
	dump_cfg_fmtint(sIgnoreRhosts, o->ignore_rhosts);
	dump_cfg_fmtint(sIgnoreUserKnownHosts, o->ignore_user_known_hosts);
	dump_cfg_fmtint(sRhostsRSAAuthentication, o->rhosts_rsa_authentication);
	dump_cfg_fmtint(sHostbasedAuthentication, o->hostbased_authentication);
	dump_cfg_fmtint(sHostbasedUsesNameFromPacketOnly,
	    o->hostbased_uses_name_from_packet_only);
	dump_cfg_fmtint(sRSAAuthentication, o->rsa_authentication);
	dump_cfg_fmtint(sPubkeyAuthentication, o->pubkey_authentication);
#ifdef KRB5
	dump_cfg_fmtint(sKerberosAuthentication, o->kerberos_authentication);
	dump_cfg_fmtint(sKerberosOrLocalPasswd, o->kerberos_or_local_passwd);
	dump_cfg_fmtint(sKerberosTicketCleanup, o->kerberos_ticket_cleanup);
# ifdef USE_AFS
	dump_cfg_fmtint(sKerberosGetAFSToken, o->kerberos_get_afs_token);
# endif
#endif
#ifdef GSSAPI
	dump_cfg_fmtint(sGssAuthentication, o->gss_authentication);
	dump_cfg_fmtint(sGssCleanupCreds, o->gss_cleanup_creds);
#endif
#ifdef JPAKE
	dump_cfg_fmtint(sZeroKnowledgePasswordAuthentication,
	    o->zero_knowledge_password_authentication);
#endif
	dump_cfg_fmtint(sPasswordAuthentication, o->password_authentication);
	dump_cfg_fmtint(sKbdInteractiveAuthentication,
	    o->kbd_interactive_authentication);
	dump_cfg_fmtint(sChallengeResponseAuthentication,
	    o->challenge_response_authentication);
	dump_cfg_fmtint(sPrintMotd, o->print_motd);
	dump_cfg_fmtint(sPrintLastLog, o->print_lastlog);
	dump_cfg_fmtint(sX11Forwarding, o->x11_forwarding);
	dump_cfg_fmtint(sX11UseLocalhost, o->x11_use_localhost);
	dump_cfg_fmtint(sStrictModes, o->strict_modes);
	dump_cfg_fmtint(sTCPKeepAlive, o->tcp_keep_alive);
	dump_cfg_fmtint(sEmptyPasswd, o->permit_empty_passwd);
	dump_cfg_fmtint(sPermitUserEnvironment, o->permit_user_env);
	dump_cfg_fmtint(sUseLogin, o->use_login);
	dump_cfg_fmtint(sCompression, o->compression);
	dump_cfg_fmtint(sGatewayPorts, o->gateway_ports);
	dump_cfg_fmtint(sUseDNS, o->use_dns);
	dump_cfg_fmtint(sAllowTcpForwarding, o->allow_tcp_forwarding);
	dump_cfg_fmtint(sUsePrivilegeSeparation, use_privsep);

	/* string arguments */
	dump_cfg_string(sPidFile, o->pid_file);
	dump_cfg_string(sXAuthLocation, o->xauth_location);
	dump_cfg_string(sCiphers, o->ciphers);
	dump_cfg_string(sMacs, o->macs);
	dump_cfg_string(sBanner, o->banner);
	dump_cfg_string(sAuthorizedKeysFile, o->authorized_keys_file);
	dump_cfg_string(sAuthorizedKeysFile2, o->authorized_keys_file2);
	dump_cfg_string(sForceCommand, o->adm_forced_command);

	/* string arguments requiring a lookup */
	dump_cfg_string(sLogLevel, log_level_name(o->log_level));
	dump_cfg_string(sLogFacility, log_facility_name(o->log_facility));

	/* string array arguments */
	dump_cfg_strarray(sHostKeyFile, o->num_host_key_files,
	     o->host_key_files);
	dump_cfg_strarray(sAllowUsers, o->num_allow_users, o->allow_users);
	dump_cfg_strarray(sDenyUsers, o->num_deny_users, o->deny_users);
	dump_cfg_strarray(sAllowGroups, o->num_allow_groups, o->allow_groups);
	dump_cfg_strarray(sDenyGroups, o->num_deny_groups, o->deny_groups);
	dump_cfg_strarray(sAcceptEnv, o->num_accept_env, o->accept_env);

	/* other arguments */
	for (i = 0; i < o->num_subsystems; i++)
		printf("subsystem %s %s\n", o->subsystem_name[i],
		    o->subsystem_args[i]);

	printf("maxstartups %d:%d:%d\n", o->max_startups_begin,
	    o->max_startups_rate, o->max_startups);

	for (i = 0; tunmode_desc[i].val != -1; i++)
		if (tunmode_desc[i].val == o->permit_tun) {
			s = tunmode_desc[i].text;
			break;
		}
	dump_cfg_string(sPermitTunnel, s);

	channel_print_adm_permitted_opens();
}