/*
 * Copyright (c) 1997-2005 Kungliga Tekniska Högskolan
 * (Royal Institute of Technology, Stockholm, Sweden). 
 *
 * All rights reserved. 
 *
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted provided that the following conditions 
 * are met: 
 *
 * 1. Redistributions of source code must retain the above copyright 
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright 
 *    notice, this list of conditions and the following disclaimer in the 
 *    documentation and/or other materials provided with the distribution. 
 *
 * 3. Neither the name of the Institute nor the names of its contributors 
 *    may be used to endorse or promote products derived from this software 
 *    without specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 
 * SUCH DAMAGE. 
 */

#include "kdc_locl.h"
#include <getarg.h>
#include <parse_bytes.h>

RCSID("$Id$");

struct dbinfo {
    char *realm;
    char *dbname;
    char *mkey_file;
    struct dbinfo *next;
};

static const char *config_file;	/* location of kdc config file */

static int require_preauth = -1; /* 1 == require preauth for all principals */
static char *max_request_str;	/* `max_request' as a string */

static const char *trpolicy_str;

static int disable_des = -1;
static int enable_v4 = -1;
static int enable_kaserver = -1;
static int enable_524 = -1;
static int enable_v4_cross_realm = -1;

static int builtin_hdb_flag;
static int help_flag;
static int version_flag;

static struct getarg_strings addresses_str;	/* addresses to listen on */

static char *v4_realm;

static struct getargs args[] = {
    { 
	"config-file",	'c',	arg_string,	&config_file, 
	"location of config file",	"file" 
    },
    { 
	"require-preauth",	'p',	arg_negative_flag, &require_preauth, 
	"don't require pa-data in as-reqs"
    },
    { 
	"max-request",	0,	arg_string, &max_request, 
	"max size for a kdc-request", "size"
    },
    { "enable-http", 'H', arg_flag, &enable_http, "turn on HTTP support" },
    {	"524",		0, 	arg_negative_flag, &enable_524,
	"don't respond to 524 requests" 
    },
    {
	"kaserver", 'K', arg_flag,   &enable_kaserver,
	"enable kaserver support"
    },
    {	"kerberos4",	0, 	arg_flag, &enable_v4,
	"respond to kerberos 4 requests" 
    },
    { 
	"v4-realm",	'r',	arg_string, &v4_realm, 
	"realm to serve v4-requests for"
    },
    {	"kerberos4-cross-realm",	0, 	arg_flag,
	&enable_v4_cross_realm,
	"respond to kerberos 4 requests from foreign realms" 
    },
    {	"ports",	'P', 	arg_string, &port_str,
	"ports to listen to", "portspec"
    },
#if DETACH_IS_DEFAULT
    {
	"detach",       'D',      arg_negative_flag, &detach_from_console, 
	"don't detach from console"
    },
#else
    {
	"detach",       0 ,      arg_flag, &detach_from_console, 
	"detach from console"
    },
#endif
    {	"addresses",	0,	arg_strings, &addresses_str,
	"addresses to listen on", "list of addresses" },
    {	"disable-des",	0,	arg_flag, &disable_des,
	"disable DES" },
    {	"builtin-hdb",	0,	arg_flag,   &builtin_hdb_flag,
	"list builtin hdb backends"},
    {	"help",		'h',	arg_flag,   &help_flag },
    {	"version",	'v',	arg_flag,   &version_flag }
};

static int num_args = sizeof(args) / sizeof(args[0]);

static void
usage(int ret)
{
    arg_printusage (args, num_args, NULL, "");
    exit (ret);
}

static void
get_dbinfo(krb5_context context, krb5_kdc_configuration *config)
{
    const krb5_config_binding *top_binding = NULL;
    const krb5_config_binding *db_binding;
    const krb5_config_binding *default_binding = NULL;
    struct dbinfo *di, **dt;
    const char *default_dbname = HDB_DEFAULT_DB;
    const char *default_mkey = HDB_DB_DIR "/m-key";
    const char *p;
    krb5_error_code ret;
    
    struct dbinfo *databases = NULL;

    dt = &databases;
    while((db_binding = (const krb5_config_binding *)
	   krb5_config_get_next(context, NULL, &top_binding, 
				krb5_config_list, 
				"kdc", 
				"database",
				NULL))) {
	p = krb5_config_get_string(context, db_binding, "realm", NULL);
	if(p == NULL) {
	    if(default_binding) {
		krb5_warnx(context, "WARNING: more than one realm-less "
			   "database specification");
		krb5_warnx(context, "WARNING: using the first encountered");
	    } else
		default_binding = db_binding;
	    continue;
	}
	di = calloc(1, sizeof(*di));
	di->realm = strdup(p);
	p = krb5_config_get_string(context, db_binding, "dbname", NULL);
	if(p)
	    di->dbname = strdup(p);
	p = krb5_config_get_string(context, db_binding, "mkey_file", NULL);
	if(p)
	    di->mkey_file = strdup(p);
	*dt = di;
	dt = &di->next;
    }
    if(default_binding) {
	di = calloc(1, sizeof(*di));
	p = krb5_config_get_string(context, default_binding, "dbname", NULL);
	if(p) {
	    di->dbname = strdup(p);
	    default_dbname = p;
	}
	p = krb5_config_get_string(context, default_binding, "mkey_file", NULL);
	if(p) {
	    di->mkey_file = strdup(p);
	    default_mkey = p;
	}
	*dt = di;
	dt = &di->next;
    } else if(databases == NULL) {
	/* if there are none specified, use some default */
	di = calloc(1, sizeof(*di));
	di->dbname = strdup(default_dbname);
	di->mkey_file = strdup(default_mkey);
	*dt = di;
	dt = &di->next;
    }
    for(di = databases; di; di = di->next) {
	if(di->dbname == NULL)
	    di->dbname = strdup(default_dbname);
	if(di->mkey_file == NULL) {
	    p = strrchr(di->dbname, '.');
	    if(p == NULL || strchr(p, '/') != NULL)
		/* final pathname component does not contain a . */
		asprintf(&di->mkey_file, "%s.mkey", di->dbname);
	    else
		/* the filename is something.else, replace .else with
                   .mkey */
		asprintf(&di->mkey_file, "%.*s.mkey", 
			 (int)(p - di->dbname), di->dbname);
	}
    }

    if (databases == NULL) {
	config->db = malloc(sizeof(*config->db));
	config->num_db = 1;
	ret = hdb_create(context, &config->db[0], NULL);
	if(ret)
	    krb5_err(context, 1, ret, "hdb_create %s", HDB_DEFAULT_DB);
	ret = hdb_set_master_keyfile(context, config->db[0], NULL);
	if (ret)
	    krb5_err(context, 1, ret, "hdb_set_master_keyfile");
    } else {
	struct dbinfo *d;
	int i;
	/* count databases */
	for(d = databases, i = 0; d; d = d->next, i++);
	config->db = malloc(i * sizeof(*config->db));
	for(d = databases, config->num_db = 0; d; d = d->next, config->num_db++) {
	    ret = hdb_create(context, &config->db[config->num_db], d->dbname);
	    if(ret)
		krb5_err(context, 1, ret, "hdb_create %s", d->dbname);
	    ret = hdb_set_master_keyfile(context, config->db[config->num_db], d->mkey_file);
	    if (ret)
		krb5_err(context, 1, ret, "hdb_set_master_keyfile");
	}
    }

}

static void
add_one_address (krb5_context context, const char *str, int first)
{
    krb5_error_code ret;
    krb5_addresses tmp;

    ret = krb5_parse_address (context, str, &tmp);
    if (ret)
	krb5_err (context, 1, ret, "parse_address `%s'", str);
    if (first)
	krb5_copy_addresses(context, &tmp, &explicit_addresses);
    else
	krb5_append_addresses(context, &explicit_addresses, &tmp);
    krb5_free_addresses (context, &tmp);
}

krb5_kdc_configuration *
configure(krb5_context context, int argc, char **argv)
{
    krb5_kdc_configuration *config = malloc(sizeof(*config));
    krb5_error_code ret;
    int optidx = 0;
    const char *p;
    
    if (!config) {
	return NULL;
    }
    
    krb5_kdc_default_config(config);

    while(getarg(args, num_args, argc, argv, &optidx))
	warnx("error at argument `%s'", argv[optidx]);

    if(help_flag)
	usage (0);

    if (version_flag) {
	print_version(NULL);
	exit(0);
    }

    if (builtin_hdb_flag) {
	char *list;
	ret = hdb_list_builtin(context, &list);
	if (ret)
	    krb5_err(context, 1, ret, "listing builtin hdb backends");
	printf("builtin hdb backends: %s\n", list);
	free(list);
	exit(0);
    }

    argc -= optidx;
    argv += optidx;

    if (argc != 0)
	usage(1);
    
    {
	char **files;

	if(config_file == NULL)
	    config_file = _PATH_KDC_CONF;

	ret = krb5_prepend_config_files_default(config_file, &files);
	if (ret)
	    krb5_err(context, 1, ret, "getting configuration files");
	    
	ret = krb5_set_config_files(context, files);
	krb5_free_config_files(files);
	if(ret) 
	    krb5_err(context, 1, ret, "reading configuration files");
    }

    kdc_openlog(context, config);

    get_dbinfo(context, config);
    
    if(max_request_str)
	max_request = parse_bytes(max_request_str, NULL);

    if(max_request == 0){
	p = krb5_config_get_string (context,
				    NULL,
				    "kdc",
				    "max-request",
				    NULL);
	if(p)
	    max_request = parse_bytes(p, NULL);
    }
    
    if(require_preauth == -1) {
	config->require_preauth = krb5_config_get_bool_default(context, NULL, 
							       config->require_preauth,
							       "kdc", 
							       "require-preauth", NULL);
    } else {
	config->require_preauth = require_preauth;
    }

    if(port_str == NULL){
	p = krb5_config_get_string(context, NULL, "kdc", "ports", NULL);
	if (p != NULL)
	    port_str = strdup(p);
    }

    explicit_addresses.len = 0;

    if (addresses_str.num_strings) {
	int i;

	for (i = 0; i < addresses_str.num_strings; ++i)
	    add_one_address (context, addresses_str.strings[i], i == 0);
	free_getarg_strings (&addresses_str);
    } else {
	char **foo = krb5_config_get_strings (context, NULL,
					      "kdc", "addresses", NULL);

	if (foo != NULL) {
	    add_one_address (context, *foo++, TRUE);
	    while (*foo)
		add_one_address (context, *foo++, FALSE);
	}
    }

    if(enable_v4 == -1) {
	config->enable_v4 = krb5_config_get_bool_default(context, NULL, 
							 config->enable_v4, 
							 "kdc", 
							 "enable-kerberos4", 
							 NULL);
    } else {
	config->enable_v4 = enable_v4;
    }

    if(enable_v4_cross_realm == -1) {
	config->enable_v4_cross_realm =
	    krb5_config_get_bool_default(context, NULL,
					 config->enable_v4_cross_realm, 
					 "kdc", 
					 "enable-kerberos4-cross-realm",
					 NULL);
    } else {
	config->enable_v4_cross_realm = enable_v4_cross_realm;
    }

    if(enable_524 == -1) {
	config->enable_524 = krb5_config_get_bool_default(context, NULL, 
							  config->enable_v4, 
							  "kdc", "enable-524", 
							  NULL);
    } else {
	config->enable_524 = enable_524;
    }

    if(enable_http == -1)
	enable_http = krb5_config_get_bool(context, NULL, "kdc", 
					   "enable-http", NULL);

    config->enable_digest = 
	krb5_config_get_bool_default(context, NULL, 
				     FALSE, 
				     "kdc", 
				     "enable-digest", NULL);

    {
	const char *digests;

	digests = krb5_config_get_string(context, NULL, 
					 "kdc", 
					 "digests_allowed", NULL);
	if (digests == NULL)
	    digests = "ntlm-v2";
	config->digests_allowed = parse_flags(digests,
					      _kdc_digestunits,
					      0);
	if (config->digests_allowed == -1) {
	    kdc_log(context, config, 0,
		    "unparsable digest units (%s), turning off digest",
		    digests);
	    config->enable_digest = 0;
	} else if (config->digests_allowed == 0) {
	    kdc_log(context, config, 0,
		    "no digest enable, turning digest off",
		    digests);
	    config->enable_digest = 0;
	}
    }

    config->enable_kx509 = 
	krb5_config_get_bool_default(context, NULL, 
				     FALSE, 
				     "kdc", 
				     "enable-kx509", NULL);

    if (config->enable_kx509) {
	config->kx509_template = krb5_config_get_string(context, NULL, 
							"kdc", 
							"kx509_template", 
							NULL);
	config->kx509_ca = krb5_config_get_string(context, NULL, 
						  "kdc", 
						  "kx509_ca", 
						  NULL);
	if (config->kx509_ca == NULL || config->kx509_template == NULL) {
	    kdc_log(context, config, 0,
		    "missing kx509 configuration, turning off");
	    config->enable_kx509 = FALSE;
	}
    }

    config->check_ticket_addresses = 
	krb5_config_get_bool_default(context, NULL, 
				     config->check_ticket_addresses, 
				     "kdc", 
				     "check-ticket-addresses", NULL);
    config->allow_null_ticket_addresses = 
	krb5_config_get_bool_default(context, NULL, 
				     config->allow_null_ticket_addresses, 
				     "kdc", 
				     "allow-null-ticket-addresses", NULL);

    config->allow_anonymous = 
	krb5_config_get_bool_default(context, NULL, 
				     config->allow_anonymous,
				     "kdc", 
				     "allow-anonymous", NULL);

    config->max_datagram_reply_length =
	krb5_config_get_int_default(context, 
				    NULL, 
				    1400,
				    "kdc",
				    "max-kdc-datagram-reply-length",
				    NULL);

    trpolicy_str = 
	krb5_config_get_string_default(context, NULL, "DEFAULT", "kdc", 
				       "transited-policy", NULL);
    if(strcasecmp(trpolicy_str, "always-check") == 0) {
	config->trpolicy = TRPOLICY_ALWAYS_CHECK;
    } else if(strcasecmp(trpolicy_str, "allow-per-principal") == 0) {
	config->trpolicy = TRPOLICY_ALLOW_PER_PRINCIPAL;
    } else if(strcasecmp(trpolicy_str, "always-honour-request") == 0) {
	config->trpolicy = TRPOLICY_ALWAYS_HONOUR_REQUEST;
    } else if(strcasecmp(trpolicy_str, "DEFAULT") == 0) { 
	/* default */
    } else {
	kdc_log(context, config, 
		0, "unknown transited-policy: %s, reverting to default (always-check)", 
		trpolicy_str);
    }
	
    if (krb5_config_get_string(context, NULL, "kdc", 
			       "enforce-transited-policy", NULL))
	krb5_errx(context, 1, "enforce-transited-policy deprecated, "
		  "use [kdc]transited-policy instead");

    if(v4_realm == NULL){
	p = krb5_config_get_string (context, NULL, 
				    "kdc",
				    "v4-realm",
				    NULL);
	if(p != NULL) {
	    config->v4_realm = strdup(p);
	    if (config->v4_realm == NULL)
		krb5_errx(context, 1, "out of memory");
	} else {
	    config->v4_realm = NULL;
	}
    } else {
	config->v4_realm = v4_realm;
    }

    if (enable_kaserver == -1) {
	config->enable_kaserver = 
	    krb5_config_get_bool_default(context, 
					 NULL, 
					 config->enable_kaserver,
					 "kdc",
					 "enable-kaserver",
					 NULL);
    } else {
	config->enable_kaserver = enable_kaserver;
    }

    config->encode_as_rep_as_tgs_rep =
	krb5_config_get_bool_default(context, NULL, 
				     config->encode_as_rep_as_tgs_rep, 
				     "kdc", 
				     "encode_as_rep_as_tgs_rep", 
				     NULL);

    config->kdc_warn_pwexpire =
	krb5_config_get_time_default (context, NULL,
				      config->kdc_warn_pwexpire,
				      "kdc",
				      "kdc_warn_pwexpire",
				      NULL);

    if(detach_from_console == -1) 
	detach_from_console = krb5_config_get_bool_default(context, NULL, 
							   DETACH_IS_DEFAULT,
							   "kdc",
							   "detach", NULL);

    if(max_request == 0)
	max_request = 64 * 1024;

    if(require_preauth != -1) {
	config->require_preauth = require_preauth;
    }
    if (port_str == NULL)
	port_str = "+";

#ifdef PKINIT
    config->enable_pkinit = 
	krb5_config_get_bool_default(context, 
				     NULL, 
				     config->enable_pkinit,
				     "kdc",
				     "enable-pkinit",
				     NULL);
    if (config->enable_pkinit) {
	const char *user_id, *anchors, *ocsp_file;
	char **pool_list, **revoke_list;

	user_id = krb5_config_get_string(context, NULL,
					 "kdc",
					 "pkinit_identity",
					 NULL);
	if (user_id == NULL)
	    krb5_errx(context, 1, "pkinit enabled but no identity");

	anchors = krb5_config_get_string(context, NULL,
					 "kdc",
					 "pkinit_anchors",
					 NULL);
	if (anchors == NULL)
	    krb5_errx(context, 1, "pkinit enabled but no X509 anchors");

	pool_list = krb5_config_get_strings(context, NULL,
					    "kdc",
					    "pkinit_pool",
					    NULL);

	revoke_list = krb5_config_get_strings(context, NULL,
					      "kdc",
					      "pkinit_revoke",
					      NULL);

	ocsp_file = 
	    krb5_config_get_string(context, NULL,
				   "kdc",
				   "pkinit_kdc_ocsp",
				   NULL);
	if (ocsp_file) {
	    config->pkinit_kdc_ocsp_file = strdup(ocsp_file);
	    if (config->pkinit_kdc_ocsp_file == NULL)
		krb5_errx(context, 1, "out of memory");
	}
	_kdc_pk_initialize(context, config, user_id, anchors, 
			   pool_list, revoke_list);

	krb5_config_free_strings(pool_list);
	krb5_config_free_strings(revoke_list);

	config->enable_pkinit_princ_in_cert = 
	    krb5_config_get_bool_default(context, 
					 NULL,
					 config->enable_pkinit_princ_in_cert,
					 "kdc",
					 "pkinit_principal_in_certificate",
					 NULL);
    }

    config->pkinit_dh_min_bits =
	krb5_config_get_int_default(context, 
				    NULL, 
				    0,
				    "kdc",
				    "pkinit_dh_min_bits",
				    NULL);

#endif

    if(config->v4_realm == NULL && (config->enable_kaserver || config->enable_v4)){
#ifdef KRB4
	config->v4_realm = malloc(40); /* REALM_SZ */
	if (config->v4_realm == NULL)
	    krb5_errx(context, 1, "out of memory");
	krb_get_lrealm(config->v4_realm, 1);
#else
	krb5_errx(context, 1, "No Kerberos 4 realm configured");
#endif
    }
    if(disable_des == -1)
	disable_des = krb5_config_get_bool_default(context, NULL, 
						   FALSE,
						   "kdc",
						   "disable-des", NULL);
    if(disable_des) {
	krb5_enctype_disable(context, ETYPE_DES_CBC_CRC);
	krb5_enctype_disable(context, ETYPE_DES_CBC_MD4);
	krb5_enctype_disable(context, ETYPE_DES_CBC_MD5);
	krb5_enctype_disable(context, ETYPE_DES_CBC_NONE);
	krb5_enctype_disable(context, ETYPE_DES_CFB64_NONE);
	krb5_enctype_disable(context, ETYPE_DES_PCBC_NONE);

	kdc_log(context, config, 
		0, "DES was disabled, turned off Kerberos V4, 524 "
		"and kaserver");
	config->enable_v4 = 0;
	config->enable_524 = 0;
	config->enable_kaserver = 0;
    }

    _kdc_windc_init(context);

    return config;
}