/*      $NetBSD: quota_nfs.c,v 1.5 2016/01/30 16:31:28 bouyer Exp $     */
/*-
  * Copyright (c) 2011 Manuel Bouyer
  * 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.
  *
  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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 <sys/cdefs.h>
__RCSID("$NetBSD: quota_nfs.c,v 1.5 2016/01/30 16:31:28 bouyer Exp $");

#include <sys/types.h>
#include <sys/param.h> /* XXX for DEV_BSIZE */
#include <stdlib.h>
#include <string.h>
#include <limits.h>
#include <netdb.h>
#include <errno.h>

#include <rpc/rpc.h>
#include <rpc/pmap_prot.h>
#include <rpcsvc/rquota.h>

#include <quota.h>
#include "quotapvt.h"

static uint64_t
rq_scale(uint32_t rqblocks, uint32_t rqsize)
{
        return ((uint64_t)rqblocks * rqsize) / DEV_BSIZE;
}

static uint64_t
rq_scalelimit(uint32_t rqval, uint32_t rqsize)
{
        if (rqval == 0) {
                return QUOTA_NOLIMIT;
        } else {
                return rq_scale(rqval - 1, rqsize);
        }
}

static uint64_t
rq_plainlimit(uint32_t rqval)
{
        if (rqval == 0) {
                return QUOTA_NOLIMIT;
        } else {
                return rqval - 1;
        }
}

static void
rquota_to_quotavals(const struct rquota *rq,
                    struct quotaval *blocks, struct quotaval *files)
{
        struct timeval now;

        gettimeofday(&now, NULL);

        /* blocks*/
        blocks->qv_hardlimit = rq_scalelimit(rq->rq_bhardlimit, rq->rq_bsize);
        blocks->qv_softlimit = rq_scalelimit(rq->rq_bsoftlimit, rq->rq_bsize);
        blocks->qv_usage = rq_scale(rq->rq_curblocks, rq->rq_bsize);
        blocks->qv_expiretime = rq->rq_btimeleft + now.tv_sec;
        blocks->qv_grace = QUOTA_NOTIME;

        /* inodes */
        files->qv_hardlimit = rq_plainlimit(rq->rq_fhardlimit);
        files->qv_softlimit = rq_plainlimit(rq->rq_fsoftlimit);
        files->qv_usage = rq->rq_curfiles;
        files->qv_expiretime = rq->rq_ftimeleft + now.tv_sec;
        files->qv_grace = QUOTA_NOTIME;
}
 
static int
callaurpc(const char *host, rpcprog_t prognum, rpcvers_t versnum,
    rpcproc_t procnum, xdrproc_t inproc, void *in, xdrproc_t outproc, void *out)
{
        struct sockaddr_in server_addr;
        enum clnt_stat clnt_stat;
        struct hostent *hp;
        struct timeval timeout, tottimeout;
 
        CLIENT *client = NULL;
        int sock = RPC_ANYSOCK;
 
        if ((hp = gethostbyname(host)) == NULL)
                return (int) RPC_UNKNOWNHOST;
        timeout.tv_usec = 0;
        timeout.tv_sec = 6;
        memmove(&server_addr.sin_addr, hp->h_addr, hp->h_length);
        server_addr.sin_family = AF_INET;
        server_addr.sin_port =  0;

        if ((client = clntudp_create(&server_addr, prognum,
            versnum, timeout, &sock)) == NULL)
                return (int) rpc_createerr.cf_stat;

        client->cl_auth = authunix_create_default();
        tottimeout.tv_sec = 25;
        tottimeout.tv_usec = 0;
        clnt_stat = clnt_call(client, procnum, inproc, in,
            outproc, out, tottimeout);
 
        return (int) clnt_stat;
}

int
__quota_nfs_get(struct quotahandle *qh, const struct quotakey *qk,
                struct quotaval *qv)
{
        struct getquota_args gq_args;
        struct ext_getquota_args ext_gq_args;
        struct getquota_rslt gq_rslt;
        struct quotaval blocks, inodes;
        char *host, *path;
        int ret, rpcqtype;
        int sverrno;

        switch (qk->qk_idtype) {
            case QUOTA_IDTYPE_USER:
                rpcqtype = RQUOTA_USRQUOTA;
                break;
            case QUOTA_IDTYPE_GROUP:
                rpcqtype = RQUOTA_GRPQUOTA;
                break;
            default:
                errno = EINVAL;
                return -1;
        }

        switch (qk->qk_objtype) {
            case QUOTA_OBJTYPE_BLOCKS:
            case QUOTA_OBJTYPE_FILES:
                break;
            default:
                errno = EINVAL;
                return -1;
        }

        /*
         * must be some form of "hostname:/path"
         */
        path = strdup(qh->qh_mountdevice);
        if (path == NULL) {
                errno = ENOMEM;
                return -1;
        }
        host = strsep(&path, ":");
        if (path == NULL) {
                free(host);
                errno = EINVAL;
                return -1;
        }

        ext_gq_args.gqa_pathp = path;
        ext_gq_args.gqa_id = qk->qk_id;
        ext_gq_args.gqa_type = rpcqtype;
        ret = callaurpc(host, RQUOTAPROG, EXT_RQUOTAVERS,
            RQUOTAPROC_GETQUOTA, (xdrproc_t)xdr_ext_getquota_args,
            &ext_gq_args, (xdrproc_t)xdr_getquota_rslt, &gq_rslt);
        if ((ret == RPC_PROGVERSMISMATCH || ret == RPC_PROGNOTREGISTERED)
            && rpcqtype == RQUOTA_USRQUOTA) {
                /* try RQUOTAVERS */
                gq_args.gqa_pathp = path;
                gq_args.gqa_uid = qk->qk_id;
                ret = callaurpc(host, RQUOTAPROG, RQUOTAVERS,
                    RQUOTAPROC_GETQUOTA, (xdrproc_t)xdr_getquota_args,
                    &gq_args, (xdrproc_t)xdr_getquota_rslt, &gq_rslt);
        }
        sverrno = errno;
        free(host);

        if (ret != RPC_SUCCESS) {
                /*
                 * Remap some error codes for callers convenience:
                 *  - if the file server does not support any quotas at all,
                 *    return ENOENT
                 *  - if the server can not be reached something is very
                 *    wrong - or we are run inside a virtual rump network
                 *    but querying an NFS mount from the host. Make sure
                 *    to fail silently and return ENOENT as well.
                 */
                if (ret == RPC_SYSTEMERROR
                    && rpc_createerr.cf_error.re_errno == EHOSTUNREACH)
                        sverrno = ENOENT;
                else if (sverrno == ENOTCONN)
                        sverrno = ENOENT;
                errno = sverrno;
                return -1;
        }

        switch (gq_rslt.status) {
        case Q_NOQUOTA:
                quotaval_clear(qv);
                return 0;
        case Q_EPERM:
                errno = EACCES;
                return -1;
        case Q_OK:
                rquota_to_quotavals(&gq_rslt.getquota_rslt_u.gqr_rquota,
                                    &blocks, &inodes);
                if (qk->qk_objtype == QUOTA_OBJTYPE_BLOCKS) {
                        *qv = blocks;
                } else {
                        *qv = inodes;
                }
                return 0;
        default:
                break;
        }
        /* XXX not exactly a good errno */
        errno = ERANGE;
        return -1;
}