/*
 * Copyright (c) 2005, PADL Software Pty Ltd.
 * All rights reserved.
 *
 * Portions Copyright (c) 2009 Apple Inc. 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 PADL Software 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 PADL SOFTWARE 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 PADL SOFTWARE 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 "kcm_locl.h"
#include <getarg.h>
#include <parse_bytes.h>

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

size_t max_request = 0;         /* maximal size of a request */
char *socket_path = NULL;
char *door_path = NULL;

static char *max_request_str;   /* `max_request' as a string */

#ifdef SUPPORT_DETACH
int detach_from_console = -1;
#define DETACH_IS_DEFAULT FALSE
#endif

static const char *system_cache_name = NULL;
static const char *system_keytab = NULL;
static const char *system_principal = NULL;
static const char *system_server = NULL;
static const char *system_perms = NULL;
static const char *system_user = NULL;
static const char *system_group = NULL;

static const char *renew_life = NULL;
static const char *ticket_life = NULL;

int launchd_flag = 0;
int disallow_getting_krbtgt = 0;
int name_constraints = -1;

static int help_flag;
static int version_flag;

static struct getargs args[] = {
    {
        "cache-name",   0,      arg_string,     &system_cache_name,
        "system cache name", "cachename"
    },
    {
        "config-file",  'c',    arg_string,     &config_file,
        "location of config file",      "file"
    },
    {
        "group",        'g',    arg_string,     &system_group,
        "system cache group",   "group"
    },
    {
        "max-request",  0,      arg_string, &max_request,
        "max size for a kcm-request", "size"
    },
    {
        "launchd",      0,      arg_flag, &launchd_flag,
        "when in use by launchd"
    },
#ifdef SUPPORT_DETACH
#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
#endif
    {   "help",         'h',    arg_flag,   &help_flag },
    {
        "system-principal",     'k',    arg_string,     &system_principal,
        "system principal name",        "principal"
    },
    {
        "lifetime",     'l', arg_string, &ticket_life,
        "lifetime of system tickets", "time"
    },
    {
        "mode",         'm', arg_string, &system_perms,
        "octal mode of system cache", "mode"
    },
    {
        "name-constraints",     'n', arg_negative_flag, &name_constraints,
        "disable credentials cache name constraints"
    },
    {
        "disallow-getting-krbtgt", 0, arg_flag, &disallow_getting_krbtgt,
        "disable fetching krbtgt from the cache"
    },
    {
        "renewable-life",       'r', arg_string, &renew_life,
        "renewable lifetime of system tickets", "time"
    },
    {
        "socket-path",          's', arg_string, &socket_path,
        "path to kcm domain socket", "path"
    },
#ifdef HAVE_DOOR_CREATE
    {
        "door-path",            's', arg_string, &door_path,
        "path to kcm door", "path"
    },
#endif
    {
        "server",               'S', arg_string, &system_server,
        "server to get system ticket for", "principal"
    },
    {
        "keytab",       't',    arg_string,     &system_keytab,
        "system keytab name",   "keytab"
    },
    {
        "user",         'u',    arg_string,     &system_user,
        "system cache owner",   "user"
    },
    {   "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 int parse_owners(kcm_ccache ccache)
{
    uid_t uid = 0;
    gid_t gid = 0;
    struct passwd *pw;
    struct group *gr;
    int uid_p = 0;
    int gid_p = 0;

    if (system_user != NULL) {
        if (isdigit((unsigned char)system_user[0])) {
            pw = getpwuid(atoi(system_user));
        } else {
            pw = getpwnam(system_user);
        }
        if (pw == NULL) {
            return errno;
        }

        system_user = strdup(pw->pw_name);
        if (system_user == NULL) {
            return ENOMEM;
        }

        uid = pw->pw_uid; uid_p = 1;
        gid = pw->pw_gid; gid_p = 1;
    }

    if (system_group != NULL) {
        if (isdigit((unsigned char)system_group[0])) {
            gr = getgrgid(atoi(system_group));
        } else {
            gr = getgrnam(system_group);
        }
        if (gr == NULL) {
            return errno;
        }

        gid = gr->gr_gid; gid_p = 1;
    }

    if (uid_p)
        ccache->uid = uid;
    else
        ccache->uid = 0; /* geteuid() XXX */

    if (gid_p)
        ccache->gid = gid;
    else
        ccache->gid = 0; /* getegid() XXX */

    return 0;
}

static const char *
kcm_system_config_get_string(const char *string)
{
    return krb5_config_get_string(kcm_context, NULL, "kcm",
                                  "system_ccache", string, NULL);
}

static krb5_error_code
ccache_init_system(void)
{
    kcm_ccache ccache;
    krb5_error_code ret;

    if (system_cache_name == NULL)
        system_cache_name = kcm_system_config_get_string("cc_name");

    ret = kcm_ccache_new(kcm_context,
                         system_cache_name ? system_cache_name : "SYSTEM",
                         &ccache);
    if (ret)
        return ret;

    ccache->flags |= KCM_FLAGS_OWNER_IS_SYSTEM;
    ccache->flags |= KCM_FLAGS_USE_KEYTAB;

    ret = parse_owners(ccache);
    if (ret)
        return ret;

    ret = krb5_parse_name(kcm_context, system_principal, &ccache->client);
    if (ret) {
        kcm_release_ccache(kcm_context, ccache);
        return ret;
    }

    if (system_server == NULL)
        system_server = kcm_system_config_get_string("server");

    if (system_server != NULL) {
        ret = krb5_parse_name(kcm_context, system_server, &ccache->server);
        if (ret) {
            kcm_release_ccache(kcm_context, ccache);
            return ret;
        }
    }

    if (system_keytab == NULL)
        system_keytab = kcm_system_config_get_string("keytab_name");

    if (system_keytab != NULL) {
        ret = krb5_kt_resolve(kcm_context, system_keytab, &ccache->key.keytab);
    } else {
        ret = krb5_kt_default(kcm_context, &ccache->key.keytab);
    }
    if (ret) {
        kcm_release_ccache(kcm_context, ccache);
        return ret;
    }

    if (renew_life == NULL)
        renew_life = kcm_system_config_get_string("renew_life");

    if (renew_life == NULL)
        renew_life = "1 month";

    if (renew_life != NULL) {
        ccache->renew_life = parse_time(renew_life, "s");
        if (ccache->renew_life < 0) {
            kcm_release_ccache(kcm_context, ccache);
            return EINVAL;
        }
    }

    if (ticket_life == NULL)
        ticket_life = kcm_system_config_get_string("ticket_life");

    if (ticket_life != NULL) {
        ccache->tkt_life = parse_time(ticket_life, "s");
        if (ccache->tkt_life < 0) {
            kcm_release_ccache(kcm_context, ccache);
            return EINVAL;
        }
    }

    if (system_perms == NULL)
        system_perms = kcm_system_config_get_string("mode");

    if (system_perms != NULL) {
        int mode;

        if (sscanf(system_perms, "%o", &mode) != 1)
            return EINVAL;

        ccache->mode = mode;
    }

    if (disallow_getting_krbtgt == -1) {
        disallow_getting_krbtgt =
            krb5_config_get_bool_default(kcm_context, NULL, FALSE, "kcm",
                                         "disallow-getting-krbtgt", NULL);
    }

    /* enqueue default actions for credentials cache */
    ret = kcm_ccache_enqueue_default(kcm_context, ccache, NULL);

    kcm_release_ccache(kcm_context, ccache); /* retained by event queue */

    return ret;
}

void
kcm_configure(int argc, char **argv)
{
    krb5_error_code ret;
    int optind = 0;
    const char *p;

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

    if(help_flag)
        usage (0);

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

    argc -= optind;
    argv += optind;

    if (argc != 0)
        usage(1);

    {
        char **files;

        if(config_file == NULL)
            config_file = _PATH_KCM_CONF;

        ret = krb5_prepend_config_files_default(config_file, &files);
        if (ret)
            krb5_err(kcm_context, 1, ret, "getting configuration files");

        ret = krb5_set_config_files(kcm_context, files);
        krb5_free_config_files(files);
        if(ret)
            krb5_err(kcm_context, 1, ret, "reading configuration files");
    }

    if(max_request_str)
        max_request = parse_bytes(max_request_str, NULL);

    if(max_request == 0){
        p = krb5_config_get_string (kcm_context,
                                    NULL,
                                    "kcm",
                                    "max-request",
                                    NULL);
        if(p)
            max_request = parse_bytes(p, NULL);
    }

    if (system_principal == NULL) {
        system_principal = kcm_system_config_get_string("principal");
    }

    if (system_principal != NULL) {
        ret = ccache_init_system();
        if (ret)
            krb5_err(kcm_context, 1, ret, "initializing system ccache");
    }

#ifdef SUPPORT_DETACH
    if(detach_from_console == -1)
        detach_from_console = krb5_config_get_bool_default(kcm_context, NULL,
                                                           DETACH_IS_DEFAULT,
                                                           "kcm",
                                                           "detach", NULL);
#endif
    kcm_openlog();
    if(max_request == 0)
        max_request = 64 * 1024;
}