/*
 * by Manuel Bouyer (bouyer@ensta.fr)
 *
 * There is no copyright, you can use it as you want.
 */

#include <sys/param.h>
#include <sys/mount.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/socket.h>

#include <ufs/ufs/quota.h>
#include <rpc/rpc.h>
#include <rpcsvc/rquota.h>
#include <arpa/inet.h>
#include <netdb.h>

#include <ctype.h>
#include <errno.h>
#include <fstab.h>
#include <grp.h>
#include <libutil.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <err.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>

static void rquota_service_1(struct svc_req *request, SVCXPRT *transp);
static void rquota_service_2(struct svc_req *request, SVCXPRT *transp);
static void sendquota(struct svc_req *request, SVCXPRT *transp);
static void sendquota_extended(struct svc_req *request, SVCXPRT *transp);
static int getfsquota(int type, long id, char *path, struct dqblk *dqblk);

static int from_inetd = 1;
static int debug = 0;

static void
cleanup(int sig)
{

        (void)sig;
        (void)rpcb_unset(RQUOTAPROG, RQUOTAVERS, NULL);
        exit(0);
}

int
main(int argc, char **argv)
{
        SVCXPRT *transp;
        int ok;
        struct sockaddr_storage from;
        socklen_t fromlen;
        int vers;
        int ch;

        while ((ch = getopt(argc, argv, "d")) != -1) {
                switch (ch) {
                case 'd':
                        debug++;
                        break;
                default:
                        break;
                }
        }

        fromlen = sizeof(from);
        if (getsockname(0, (struct sockaddr *)&from, &fromlen) < 0)
                from_inetd = 0;

        if (!from_inetd) {
                if (!debug)
                        daemon(0, 0);
                (void)rpcb_unset(RQUOTAPROG, RQUOTAVERS, NULL);
                (void)signal(SIGINT, cleanup);
                (void)signal(SIGTERM, cleanup);
                (void)signal(SIGHUP, cleanup);
        }

        openlog("rpc.rquotad", LOG_CONS|LOG_PID, LOG_DAEMON);

        /* create and register the service */
        if (from_inetd) {
                transp = svc_tli_create(0, NULL, NULL, 0, 0);
                if (transp == NULL) {
                        syslog(LOG_ERR, "couldn't create udp service.");
                        exit(1);
                }
                vers = RQUOTAVERS;
                ok = svc_reg(transp, RQUOTAPROG, RQUOTAVERS,
                    rquota_service_1, NULL);
                if (ok) {
                        vers = EXT_RQUOTAVERS;
                        ok = svc_reg(transp, RQUOTAPROG, EXT_RQUOTAVERS,
                                     rquota_service_2, NULL);
                }
        } else {
                vers = RQUOTAVERS;
                ok = svc_create(rquota_service_1,
                    RQUOTAPROG, RQUOTAVERS, "udp");
                if (ok) {
                        vers = EXT_RQUOTAVERS;
                        ok = svc_create(rquota_service_2,
                                        RQUOTAPROG, EXT_RQUOTAVERS, "udp");

                }
        }
        if (!ok) {
                syslog(LOG_ERR,
                    "unable to register (RQUOTAPROG, %s, %s)",
                       vers == RQUOTAVERS ? "RQUOTAVERS" : "EXT_RQUOTAVERS",
                       from_inetd ? "(inetd)" : "udp");
                exit(1);
        }

        svc_run();
        syslog(LOG_ERR, "svc_run returned");
        exit(1);
}

static void
rquota_service_2(struct svc_req *request, SVCXPRT *transp)
{

        switch (request->rq_proc) {
        case NULLPROC:
                (void)svc_sendreply(transp, (xdrproc_t)xdr_void, (char *)NULL);
                break;
        case RQUOTAPROC_GETQUOTA:
        case RQUOTAPROC_GETACTIVEQUOTA:
                sendquota_extended(request, transp);
                break;
        default:
                svcerr_noproc(transp);
                break;
        }
        if (from_inetd)
                exit(0);
}

static void
rquota_service_1(struct svc_req *request, SVCXPRT *transp)
{

        switch (request->rq_proc) {
        case NULLPROC:
                (void)svc_sendreply(transp, (xdrproc_t)xdr_void, (char *)NULL);
                break;
        case RQUOTAPROC_GETQUOTA:
        case RQUOTAPROC_GETACTIVEQUOTA:
                sendquota(request, transp);
                break;
        default:
                svcerr_noproc(transp);
                break;
        }
        if (from_inetd)
                exit(0);
}

/* read quota for the specified id, and send it */
static void
sendquota(struct svc_req *request, SVCXPRT *transp)
{
        struct getquota_args getq_args;
        struct getquota_rslt getq_rslt;
        struct dqblk dqblk;
        struct timeval timev;
        int scale;

        bzero(&getq_args, sizeof(getq_args));
        if (!svc_getargs(transp, (xdrproc_t)xdr_getquota_args, &getq_args)) {
                svcerr_decode(transp);
                return;
        }
        if (request->rq_cred.oa_flavor != AUTH_UNIX) {
                /* bad auth */
                getq_rslt.status = Q_EPERM;
        } else if (!getfsquota(USRQUOTA, getq_args.gqa_uid, getq_args.gqa_pathp, &dqblk)) {
                /* failed, return noquota */
                getq_rslt.status = Q_NOQUOTA;
        } else {
                gettimeofday(&timev, NULL);
                getq_rslt.status = Q_OK;
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_active = TRUE;
                scale = 1 << flsll(dqblk.dqb_bhardlimit >> 32);
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_bsize =
                    DEV_BSIZE * scale;
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_bhardlimit =
                    dqblk.dqb_bhardlimit / scale;
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_bsoftlimit =
                    dqblk.dqb_bsoftlimit / scale;
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_curblocks =
                    dqblk.dqb_curblocks / scale;
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_fhardlimit =
                    dqblk.dqb_ihardlimit;
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_fsoftlimit =
                    dqblk.dqb_isoftlimit;
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_curfiles =
                    dqblk.dqb_curinodes;
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_btimeleft =
                    dqblk.dqb_btime - timev.tv_sec;
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_ftimeleft =
                    dqblk.dqb_itime - timev.tv_sec;
        }
        if (!svc_sendreply(transp, (xdrproc_t)xdr_getquota_rslt, &getq_rslt))
                svcerr_systemerr(transp);
        if (!svc_freeargs(transp, (xdrproc_t)xdr_getquota_args, &getq_args)) {
                syslog(LOG_ERR, "unable to free arguments");
                exit(1);
        }
}

static void
sendquota_extended(struct svc_req *request, SVCXPRT *transp)
{
        struct ext_getquota_args getq_args;
        struct getquota_rslt getq_rslt;
        struct dqblk dqblk;
        struct timeval timev;
        int scale;

        bzero(&getq_args, sizeof(getq_args));
        if (!svc_getargs(transp, (xdrproc_t)xdr_ext_getquota_args, &getq_args)) {
                svcerr_decode(transp);
                return;
        }
        if (request->rq_cred.oa_flavor != AUTH_UNIX) {
                /* bad auth */
                getq_rslt.status = Q_EPERM;
        } else if (!getfsquota(getq_args.gqa_type, getq_args.gqa_id, getq_args.gqa_pathp, &dqblk)) {
                /* failed, return noquota */
                getq_rslt.status = Q_NOQUOTA;
        } else {
                gettimeofday(&timev, NULL);
                getq_rslt.status = Q_OK;
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_active = TRUE;
                scale = 1 << flsll(dqblk.dqb_bhardlimit >> 32);
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_bsize =
                    DEV_BSIZE * scale;
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_bhardlimit =
                    dqblk.dqb_bhardlimit / scale;
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_bsoftlimit =
                    dqblk.dqb_bsoftlimit / scale;
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_curblocks =
                    dqblk.dqb_curblocks / scale;
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_fhardlimit =
                    dqblk.dqb_ihardlimit;
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_fsoftlimit =
                    dqblk.dqb_isoftlimit;
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_curfiles =
                    dqblk.dqb_curinodes;
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_btimeleft =
                    dqblk.dqb_btime - timev.tv_sec;
                getq_rslt.getquota_rslt_u.gqr_rquota.rq_ftimeleft =
                    dqblk.dqb_itime - timev.tv_sec;
        }
        if (!svc_sendreply(transp, (xdrproc_t)xdr_getquota_rslt, &getq_rslt))
                svcerr_systemerr(transp);
        if (!svc_freeargs(transp, (xdrproc_t)xdr_getquota_args, &getq_args)) {
                syslog(LOG_ERR, "unable to free arguments");
                exit(1);
        }
}

/*
 * gets the quotas for id, filesystem path.
 * Return 0 if fail, 1 otherwise
 */
static int
getfsquota(int type, long id, char *path, struct dqblk *dqblk)
{
        struct quotafile *qf;
        /*
         * Remote quota checking is limited to mounted filesystems.
         * Since UFS and ZFS support the quota system calls, we
         * only need to make an fstab object that has the path, and
         * a blank name for the filesystem type.
         * This allows the quota_open() call to work the way we
         * expect it to.
         *
         * The static char declaration is because compiler warnings
         * don't allow passing a const char * to a char *.
         */
        int rv;
        static char blank[] = "";
        struct fstab fst;

        fst.fs_file = path;
        fst.fs_mntops = blank;
        fst.fs_vfstype = blank;
        
        if (type != USRQUOTA && type != GRPQUOTA)
                return (0);
        
        qf = quota_open(&fst, type, O_RDONLY);
        if (debug)
                warnx("quota_open(<%s, %s>, %d) returned %p",
                      fst.fs_file, fst.fs_mntops, type,
                      qf);
        if (qf == NULL)
                return (0);

        rv = quota_read(qf, dqblk, id) == 0;
        quota_close(qf);
        if (debug)
                warnx("getfsquota(%d, %ld, %s, %p) -> %d",
                      type, id, path, dqblk, rv);
        return (rv);
}