/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/* lib/krb5/ccache/ccfns.c - Dispatch methods for credentials cache code.*/
/*
 * Copyright 2000, 2007, 2008  by the Massachusetts Institute of Technology.
 * All Rights Reserved.
 *
 * Export of this software from the United States of America may
 *   require a specific license from the United States Government.
 *   It is the responsibility of any person or organization contemplating
 *   export to obtain such a license before exporting.
 *
 * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
 * distribute this software and its documentation for any purpose and
 * without fee is hereby granted, provided that the above copyright
 * notice appear in all copies and that both that copyright notice and
 * this permission notice appear in supporting documentation, and that
 * the name of M.I.T. not be used in advertising or publicity pertaining
 * to distribution of the software without specific, written prior
 * permission.  Furthermore if you modify this software you must label
 * your software as modified software and not distribute it in such a
 * fashion that it might be confused with the original M.I.T. software.
 * M.I.T. makes no representations about the suitability of
 * this software for any purpose.  It is provided "as is" without express
 * or implied warranty.
 */

#include "k5-int.h"
#include "cc-int.h"
#include "../krb/int-proto.h"

const char * KRB5_CALLCONV
krb5_cc_get_name(krb5_context context, krb5_ccache cache)
{
    return cache->ops->get_name(context, cache);
}

krb5_error_code KRB5_CALLCONV
krb5_cc_get_full_name(krb5_context context, krb5_ccache cache,
                      char **fullname_out)
{
    char *name;

    *fullname_out = NULL;
    if (asprintf(&name, "%s:%s", cache->ops->prefix,
                 cache->ops->get_name(context, cache)) < 0)
        return ENOMEM;
    *fullname_out = name;
    return 0;
}

krb5_error_code KRB5_CALLCONV
krb5_cc_gen_new(krb5_context context, krb5_ccache *cache)
{
    TRACE_CC_GEN_NEW(context, cache);
    return (*cache)->ops->gen_new(context, cache);
}

krb5_error_code KRB5_CALLCONV
krb5_cc_initialize(krb5_context context, krb5_ccache cache,
                   krb5_principal principal)
{
    TRACE_CC_INIT(context, cache, principal);
    return cache->ops->init(context, cache, principal);
}

krb5_error_code KRB5_CALLCONV
krb5_cc_destroy(krb5_context context, krb5_ccache cache)
{
    TRACE_CC_DESTROY(context, cache);
    return cache->ops->destroy(context, cache);
}

krb5_error_code KRB5_CALLCONV
krb5_cc_close(krb5_context context, krb5_ccache cache)
{
    return cache->ops->close(context, cache);
}

krb5_error_code KRB5_CALLCONV
krb5_cc_store_cred(krb5_context context, krb5_ccache cache,
                   krb5_creds *creds)
{
    TRACE_CC_STORE(context, cache, creds);
    return cache->ops->store(context, cache, creds);
}

krb5_error_code KRB5_CALLCONV
krb5_cc_retrieve_cred(krb5_context context, krb5_ccache cache,
                      krb5_flags flags, krb5_creds *mcreds,
                      krb5_creds *creds)
{
    krb5_error_code ret;
    krb5_data tmprealm;

    ret = cache->ops->retrieve(context, cache, flags, mcreds, creds);
    TRACE_CC_RETRIEVE(context, cache, mcreds, ret);
    if (ret != KRB5_CC_NOTFOUND)
        return ret;
    if (mcreds->client == NULL || mcreds->server == NULL ||
        !krb5_is_referral_realm(&mcreds->server->realm))
        return ret;

    /*
     * Retry using client's realm if service has referral realm.
     */
    tmprealm = mcreds->server->realm;
    mcreds->server->realm = mcreds->client->realm;
    ret = cache->ops->retrieve(context, cache, flags, mcreds, creds);
    TRACE_CC_RETRIEVE_REF(context, cache, mcreds, ret);
    mcreds->server->realm = tmprealm;
    return ret;
}

krb5_error_code KRB5_CALLCONV
krb5_cc_get_principal(krb5_context context, krb5_ccache cache,
                      krb5_principal *principal)
{
    return cache->ops->get_princ(context, cache, principal);
}

krb5_error_code KRB5_CALLCONV
krb5_cc_start_seq_get(krb5_context context, krb5_ccache cache,
                      krb5_cc_cursor *cursor)
{
    return cache->ops->get_first(context, cache, cursor);
}

krb5_error_code KRB5_CALLCONV
krb5_cc_next_cred(krb5_context context, krb5_ccache cache,
                  krb5_cc_cursor *cursor, krb5_creds *creds)
{
    return cache->ops->get_next(context, cache, cursor, creds);
}

krb5_error_code KRB5_CALLCONV
krb5_cc_end_seq_get(krb5_context context, krb5_ccache cache,
                    krb5_cc_cursor *cursor)
{
    return cache->ops->end_get(context, cache, cursor);
}

krb5_error_code KRB5_CALLCONV
krb5_cc_remove_cred(krb5_context context, krb5_ccache cache, krb5_flags flags,
                    krb5_creds *creds)
{
    TRACE_CC_REMOVE(context, cache, creds);
    return cache->ops->remove_cred(context, cache, flags, creds);
}

krb5_error_code KRB5_CALLCONV
krb5_cc_set_flags(krb5_context context, krb5_ccache cache, krb5_flags flags)
{
    return cache->ops->set_flags(context, cache, flags);
}

krb5_error_code KRB5_CALLCONV
krb5_cc_get_flags(krb5_context context, krb5_ccache cache, krb5_flags *flags)
{
    return cache->ops->get_flags(context, cache, flags);
}

const char * KRB5_CALLCONV
krb5_cc_get_type(krb5_context context, krb5_ccache cache)
{
    return cache->ops->prefix;
}

krb5_error_code
k5_cc_lock(krb5_context context, krb5_ccache ccache)
{
    return ccache->ops->lock(context, ccache);
}

krb5_error_code
k5_cc_unlock(krb5_context context, krb5_ccache ccache)
{
    return ccache->ops->unlock(context, ccache);
}

static const char conf_realm[] = "X-CACHECONF:";
static const char conf_name[] = "krb5_ccache_conf_data";

krb5_error_code
k5_build_conf_principals(krb5_context context, krb5_ccache id,
                         krb5_const_principal principal,
                         const char *name, krb5_creds *cred)
{
    krb5_principal client;
    krb5_error_code ret;
    char *pname = NULL;

    memset(cred, 0, sizeof(*cred));

    ret = krb5_cc_get_principal(context, id, &client);
    if (ret)
        return ret;

    if (principal) {
        ret = krb5_unparse_name(context, principal, &pname);
        if (ret)
            goto cleanup;
    }

    ret = krb5_build_principal(context, &cred->server,
                               sizeof(conf_realm) - 1, conf_realm,
                               conf_name, name, pname, (char *)NULL);
    if (ret)
        goto cleanup;
    ret = krb5_copy_principal(context, client, &cred->client);

cleanup:
    krb5_free_unparsed_name(context, pname);
    krb5_free_principal(context, client);
    return ret;
}

krb5_boolean KRB5_CALLCONV
krb5_is_config_principal(krb5_context context,
                         krb5_const_principal principal)
{
    const krb5_data *realm = &principal->realm;

    if (realm->length != sizeof(conf_realm) - 1 ||
        memcmp(realm->data, conf_realm, sizeof(conf_realm) - 1) != 0)
        return FALSE;

    if (principal->length == 0 ||
        principal->data[0].length != (sizeof(conf_name) - 1) ||
        memcmp(principal->data[0].data, conf_name, sizeof(conf_name) - 1) != 0)
        return FALSE;

    return TRUE;
}

krb5_error_code KRB5_CALLCONV
krb5_cc_set_config(krb5_context context, krb5_ccache id,
                   krb5_const_principal principal,
                   const char *key, krb5_data *data)
{
    krb5_error_code ret;
    krb5_creds cred;
    memset(&cred, 0, sizeof(cred));

    TRACE_CC_SET_CONFIG(context, id, principal, key, data);

    ret = k5_build_conf_principals(context, id, principal, key, &cred);
    if (ret)
        goto out;

    if (data == NULL) {
        ret = krb5_cc_remove_cred(context, id, 0, &cred);
    } else {
        ret = krb5int_copy_data_contents(context, data, &cred.ticket);
        if (ret)
            goto out;
        ret = krb5_cc_store_cred(context, id, &cred);
    }
out:
    krb5_free_cred_contents(context, &cred);
    return ret;
}

krb5_error_code KRB5_CALLCONV
krb5_cc_get_config(krb5_context context, krb5_ccache id,
                   krb5_const_principal principal,
                   const char *key, krb5_data *data)
{
    krb5_creds mcred, cred;
    krb5_error_code ret;

    memset(&cred, 0, sizeof(cred));
    memset(data, 0, sizeof(*data));

    ret = k5_build_conf_principals(context, id, principal, key, &mcred);
    if (ret)
        goto out;

    ret = krb5_cc_retrieve_cred(context, id, 0, &mcred, &cred);
    if (ret)
        goto out;

    ret = krb5int_copy_data_contents(context, &cred.ticket, data);
    if (ret)
        goto out;

    TRACE_CC_GET_CONFIG(context, id, principal, key, data);

out:
    krb5_free_cred_contents(context, &cred);
    krb5_free_cred_contents(context, &mcred);
    return ret;
}

krb5_error_code KRB5_CALLCONV
krb5_cc_switch(krb5_context context, krb5_ccache cache)
{
    if (cache->ops->switch_to == NULL)
        return 0;
    return cache->ops->switch_to(context, cache);
}

krb5_error_code
k5_cc_store_primary_cred(krb5_context context, krb5_ccache cache,
                         krb5_creds *creds)
{
    krb5_error_code ret;

    /* Write a start realm if we're writing a TGT and the client realm isn't
     * the same as the TGS realm. */
    if (IS_TGS_PRINC(creds->server) &&
        !data_eq(creds->client->realm, creds->server->data[1])) {
        ret = krb5_cc_set_config(context, cache, NULL,
                                 KRB5_CC_CONF_START_REALM,
                                 &creds->server->data[1]);
        if (ret)
            return ret;
    }

    return krb5_cc_store_cred(context, cache, creds);
}