/*
  Copyright (c) 2008-2012 Red Hat, Inc. <http://www.redhat.com>
  This file is part of GlusterFS.

  This file is licensed to you under your choice of the GNU Lesser
  General Public License, version 3 or any later version (LGPLv3 or
  later), or the GNU General Public License, version 2 (GPLv2), in all
  cases as published by the Free Software Foundation.
*/

#include "rpcsvc.h"
#include "logging.h"
#include "dict.h"

extern rpcsvc_auth_t *
rpcsvc_auth_null_init(rpcsvc_t *svc, dict_t *options);

extern rpcsvc_auth_t *
rpcsvc_auth_unix_init(rpcsvc_t *svc, dict_t *options);

extern rpcsvc_auth_t *
rpcsvc_auth_glusterfs_init(rpcsvc_t *svc, dict_t *options);
extern rpcsvc_auth_t *
rpcsvc_auth_glusterfs_v2_init(rpcsvc_t *svc, dict_t *options);
extern rpcsvc_auth_t *
rpcsvc_auth_glusterfs_v3_init(rpcsvc_t *svc, dict_t *options);

int
rpcsvc_auth_add_initer(struct list_head *list, char *idfier,
                       rpcsvc_auth_initer_t init)
{
    struct rpcsvc_auth_list *new = NULL;

    if ((!list) || (!init) || (!idfier))
        return -1;

    new = GF_CALLOC(1, sizeof(*new), gf_common_mt_rpcsvc_auth_list);
    if (!new) {
        return -1;
    }

    new->init = init;
    strncpy(new->name, idfier, sizeof(new->name) - 1);
    INIT_LIST_HEAD(&new->authlist);
    list_add_tail(&new->authlist, list);
    return 0;
}

int
rpcsvc_auth_add_initers(rpcsvc_t *svc)
{
    int ret = -1;

    ret = rpcsvc_auth_add_initer(
        &svc->authschemes, "auth-glusterfs",
        (rpcsvc_auth_initer_t)rpcsvc_auth_glusterfs_init);
    if (ret == -1) {
        gf_log(GF_RPCSVC, GF_LOG_ERROR, "Failed to add AUTH_GLUSTERFS");
        goto err;
    }

    ret = rpcsvc_auth_add_initer(
        &svc->authschemes, "auth-glusterfs-v2",
        (rpcsvc_auth_initer_t)rpcsvc_auth_glusterfs_v2_init);
    if (ret == -1) {
        gf_log(GF_RPCSVC, GF_LOG_ERROR, "Failed to add AUTH_GLUSTERFS-v2");
        goto err;
    }

    ret = rpcsvc_auth_add_initer(
        &svc->authschemes, "auth-glusterfs-v3",
        (rpcsvc_auth_initer_t)rpcsvc_auth_glusterfs_v3_init);
    if (ret == -1) {
        gf_log(GF_RPCSVC, GF_LOG_ERROR, "Failed to add AUTH_GLUSTERFS-v3");
        goto err;
    }

    ret = rpcsvc_auth_add_initer(&svc->authschemes, "auth-unix",
                                 (rpcsvc_auth_initer_t)rpcsvc_auth_unix_init);
    if (ret == -1) {
        gf_log(GF_RPCSVC, GF_LOG_ERROR, "Failed to add AUTH_UNIX");
        goto err;
    }

    ret = rpcsvc_auth_add_initer(&svc->authschemes, "auth-null",
                                 (rpcsvc_auth_initer_t)rpcsvc_auth_null_init);
    if (ret == -1) {
        gf_log(GF_RPCSVC, GF_LOG_ERROR, "Failed to add AUTH_NULL");
        goto err;
    }

    ret = 0;
err:
    return ret;
}

int
rpcsvc_auth_init_auth(rpcsvc_t *svc, dict_t *options,
                      struct rpcsvc_auth_list *authitem)
{
    int ret = -1;

    if ((!svc) || (!options) || (!authitem))
        return -1;

    if (!authitem->init) {
        gf_log(GF_RPCSVC, GF_LOG_ERROR, "No init function defined");
        ret = -1;
        goto err;
    }

    authitem->auth = authitem->init(svc, options);
    if (!authitem->auth) {
        gf_log(GF_RPCSVC, GF_LOG_ERROR,
               "Registration of auth failed:"
               " %s",
               authitem->name);
        ret = -1;
        goto err;
    }

    authitem->enable = 1;
    gf_log(GF_RPCSVC, GF_LOG_TRACE, "Authentication enabled: %s",
           authitem->auth->authname);

    ret = 0;
err:
    return ret;
}

int
rpcsvc_auth_init_auths(rpcsvc_t *svc, dict_t *options)
{
    int ret = -1;
    struct rpcsvc_auth_list *auth = NULL;
    struct rpcsvc_auth_list *tmp = NULL;

    if (!svc)
        return -1;

    if (list_empty(&svc->authschemes)) {
        gf_log(GF_RPCSVC, GF_LOG_WARNING, "No authentication!");
        ret = 0;
        goto err;
    }

    /* If auth null and sys are not disabled by the user, we must enable
     * it by default. This is a globally default rule, the user is still
     * allowed to disable the two for particular subvolumes.
     */
    if (!dict_get(options, "rpc-auth.auth-null")) {
        ret = dict_set_str(options, "rpc-auth.auth-null", "on");
        if (ret)
            gf_log("rpc-auth", GF_LOG_DEBUG, "dict_set failed for 'auth-nill'");
    }

    if (!dict_get(options, "rpc-auth.auth-unix")) {
        ret = dict_set_str(options, "rpc-auth.auth-unix", "on");
        if (ret)
            gf_log("rpc-auth", GF_LOG_DEBUG, "dict_set failed for 'auth-unix'");
    }

    if (!dict_get(options, "rpc-auth.auth-glusterfs")) {
        ret = dict_set_str(options, "rpc-auth.auth-glusterfs", "on");
        if (ret)
            gf_log("rpc-auth", GF_LOG_DEBUG, "dict_set failed for 'auth-unix'");
    }

    list_for_each_entry_safe(auth, tmp, &svc->authschemes, authlist)
    {
        ret = rpcsvc_auth_init_auth(svc, options, auth);
        if (ret == -1)
            goto err;
    }

    ret = 0;
err:
    return ret;
}

int
rpcsvc_set_addr_namelookup(rpcsvc_t *svc, dict_t *options)
{
    int ret;
    static char *addrlookup_key = "rpc-auth.addr.namelookup";

    if (!svc || !options)
        return (-1);

    /* By default it's disabled */
    ret = dict_get_str_boolean(options, addrlookup_key, _gf_false);
    if (ret < 0) {
        svc->addr_namelookup = _gf_false;
    } else {
        svc->addr_namelookup = ret;
    }

    if (svc->addr_namelookup)
        gf_log(GF_RPCSVC, GF_LOG_DEBUG, "Addr-Name lookup enabled");

    return (0);
}

int
rpcsvc_set_allow_insecure(rpcsvc_t *svc, dict_t *options)
{
    int ret = -1;
    char *allow_insecure_str = NULL;
    gf_boolean_t is_allow_insecure = _gf_false;

    GF_ASSERT(svc);
    GF_ASSERT(options);

    ret = dict_get_str(options, "rpc-auth-allow-insecure", &allow_insecure_str);
    if (0 == ret) {
        ret = gf_string2boolean(allow_insecure_str, &is_allow_insecure);
        if (0 == ret) {
            if (_gf_true == is_allow_insecure)
                svc->allow_insecure = 1;
            else
                svc->allow_insecure = 0;
        }
    } else {
        /* By default set allow-insecure to true */
        svc->allow_insecure = 1;

        /* setting in options for the sake of functions that look
         * configuration params for allow insecure,  eg: gf_auth
         */
        ret = dict_set_str(options, "rpc-auth-allow-insecure", "on");
        if (ret < 0)
            gf_log("rpc-auth", GF_LOG_DEBUG,
                   "dict_set failed for 'allow-insecure'");
    }

    return ret;
}

int
rpcsvc_set_root_squash(rpcsvc_t *svc, dict_t *options)
{
    int ret = -1;
    uid_t anonuid = -1;
    gid_t anongid = -1;

    GF_ASSERT(svc);
    GF_ASSERT(options);

    ret = dict_get_str_boolean(options, "root-squash", 0);
    if (ret != -1)
        svc->root_squash = ret;
    else
        svc->root_squash = _gf_false;

    ret = dict_get_uint32(options, "anonuid", &anonuid);
    if (!ret)
        svc->anonuid = anonuid;
    else
        svc->anonuid = RPC_NOBODY_UID;

    ret = dict_get_uint32(options, "anongid", &anongid);
    if (!ret)
        svc->anongid = anongid;
    else
        svc->anongid = RPC_NOBODY_GID;

    if (svc->root_squash)
        gf_log(GF_RPCSVC, GF_LOG_DEBUG,
               "root squashing enabled "
               "(uid=%d, gid=%d)",
               svc->anonuid, svc->anongid);

    return 0;
}

int
rpcsvc_auth_init(rpcsvc_t *svc, dict_t *options)
{
    int ret = -1;

    if ((!svc) || (!options))
        return -1;

    (void)rpcsvc_set_allow_insecure(svc, options);
    (void)rpcsvc_set_root_squash(svc, options);
    (void)rpcsvc_set_addr_namelookup(svc, options);
    ret = rpcsvc_auth_add_initers(svc);
    if (ret == -1) {
        gf_log(GF_RPCSVC, GF_LOG_ERROR, "Failed to add initers");
        goto out;
    }

    ret = rpcsvc_auth_init_auths(svc, options);
    if (ret == -1) {
        gf_log(GF_RPCSVC, GF_LOG_ERROR, "Failed to init auth schemes");
        goto out;
    }

out:
    return ret;
}

int
rpcsvc_auth_reconf(rpcsvc_t *svc, dict_t *options)
{
    int ret = 0;

    if ((!svc) || (!options))
        return (-1);

    ret = rpcsvc_set_allow_insecure(svc, options);
    if (ret)
        return (-1);

    ret = rpcsvc_set_root_squash(svc, options);
    if (ret)
        return (-1);

    return rpcsvc_set_addr_namelookup(svc, options);
}

rpcsvc_auth_t *
__rpcsvc_auth_get_handler(rpcsvc_request_t *req)
{
    struct rpcsvc_auth_list *auth = NULL;
    struct rpcsvc_auth_list *tmp = NULL;
    rpcsvc_t *svc = NULL;

    if (!req)
        return NULL;

    svc = req->svc;
    if (!svc) {
        gf_log(GF_RPCSVC, GF_LOG_ERROR, "!svc");
        goto err;
    }

    if (list_empty(&svc->authschemes)) {
        gf_log(GF_RPCSVC, GF_LOG_WARNING, "No authentication!");
        goto err;
    }

    list_for_each_entry_safe(auth, tmp, &svc->authschemes, authlist)
    {
        if (!auth->enable)
            continue;
        if (auth->auth->authnum == req->cred.flavour)
            goto err;
    }

    auth = NULL;
err:
    if (auth)
        return auth->auth;
    else
        return NULL;
}

rpcsvc_auth_t *
rpcsvc_auth_get_handler(rpcsvc_request_t *req)
{
    rpcsvc_auth_t *auth = NULL;

    auth = __rpcsvc_auth_get_handler(req);
    if (auth)
        goto ret;

    gf_log(GF_RPCSVC, GF_LOG_TRACE, "No auth handler: %d", req->cred.flavour);

    /* The requested scheme was not available so fall back the to one
     * scheme that will always be present.
     */
    req->cred.flavour = AUTH_NULL;
    req->verf.flavour = AUTH_NULL;
    auth = __rpcsvc_auth_get_handler(req);
ret:
    return auth;
}

int
rpcsvc_auth_request_init(rpcsvc_request_t *req, struct rpc_msg *callmsg)
{
    int32_t ret = 0;
    rpcsvc_auth_t *auth = NULL;

    if (!req || !callmsg) {
        ret = -1;
        goto err;
    }

    req->cred.flavour = rpc_call_cred_flavour(callmsg);
    req->cred.datalen = rpc_call_cred_len(callmsg);
    req->verf.flavour = rpc_call_verf_flavour(callmsg);
    req->verf.datalen = rpc_call_verf_len(callmsg);

    auth = rpcsvc_auth_get_handler(req);
    if (!auth) {
        ret = -1;
        goto err;
    }

    gf_log(GF_RPCSVC, GF_LOG_TRACE, "Auth handler: %s", auth->authname);

    if (auth->authops->request_init)
        ret = auth->authops->request_init(req, auth->authprivate);

    /* reset to auxgidlarge during
       unsersialize if necessary */
    req->auxgids = req->auxgidsmall;
    req->auxgidlarge = NULL;
err:
    return ret;
}

int
rpcsvc_authenticate(rpcsvc_request_t *req)
{
    int ret = RPCSVC_AUTH_REJECT;
    rpcsvc_auth_t *auth = NULL;
    int minauth = 0;

    if (!req)
        return ret;

    /* FIXME use rpcsvc_request_prog_minauth() */
    minauth = 0;
    if (minauth > rpcsvc_request_cred_flavour(req)) {
        gf_log(GF_RPCSVC, GF_LOG_WARNING, "Auth too weak");
        rpcsvc_request_set_autherr(req, AUTH_TOOWEAK);
        goto err;
    }

    auth = rpcsvc_auth_get_handler(req);
    if (!auth) {
        gf_log(GF_RPCSVC, GF_LOG_WARNING, "No auth handler found");
        goto err;
    }

    if (auth->authops->authenticate)
        ret = auth->authops->authenticate(req, auth->authprivate);

err:
    return ret;
}

int
rpcsvc_auth_array(rpcsvc_t *svc, char *volname, int *autharr, int arrlen)
{
    int count = 0;
    int result = RPCSVC_AUTH_REJECT;
    char *srchstr = NULL;
    int ret = 0;

    struct rpcsvc_auth_list *auth = NULL;
    struct rpcsvc_auth_list *tmp = NULL;

    if ((!svc) || (!autharr) || (!volname))
        return -1;

    memset(autharr, 0, arrlen * sizeof(int));
    if (list_empty(&svc->authschemes)) {
        gf_log(GF_RPCSVC, GF_LOG_ERROR, "No authentication!");
        goto err;
    }

    list_for_each_entry_safe(auth, tmp, &svc->authschemes, authlist)
    {
        if (count >= arrlen)
            break;

        result = gf_asprintf(&srchstr, "rpc-auth.%s.%s", auth->name, volname);
        if (result == -1) {
            count = -1;
            goto err;
        }

        ret = dict_get_str_boolean(svc->options, srchstr, 0xC00FFEE);
        GF_FREE(srchstr);

        switch (ret) {
            case _gf_true:
                autharr[count] = auth->auth->authnum;
                ++count;
                break;

            default:
                /* nothing to do */
                break;
        }
    }

err:
    return count;
}

gid_t *
rpcsvc_auth_unix_auxgids(rpcsvc_request_t *req, int *arrlen)
{
    if ((!req) || (!arrlen))
        return NULL;

    /* In case of AUTH_NULL auxgids are not used */
    switch (req->cred.flavour) {
        case AUTH_UNIX:
        case AUTH_GLUSTERFS:
        case AUTH_GLUSTERFS_v2:
        case AUTH_GLUSTERFS_v3:
            break;
        default:
            gf_log("rpc", GF_LOG_DEBUG, "auth type not unix or glusterfs");
            return NULL;
    }

    *arrlen = req->auxgidcount;
    if (*arrlen == 0)
        return NULL;

    return &req->auxgids[0];
}