ProfitPress Mega CDROM2 …eeware (MSDOS)(1992)(Eng)/ProfitPress-MegaCDROM2.B6I/MISC/NETWORK/SOSS31.ZIP/SRC/MOUNTD.C

C/C++ Source or Header | 1991-02-22 | 4.8 KB | 190 lines

/*
 *  mountd.c --
 *      Mount daemon program for PC NFS.  Runs on top of the net daemon
 *      (netd.c).  This is a partial implementation of the UNIX mount
 *      daemon mountd(8c).
 *
 *  Author:
 *      See-Mong Tan, 6/12/88]
 */

#include "common.h"

static void expreply (struct svc_req *, SVCXPRT *);

/*
 *  bool_t mountd_init() --
 *      Mount daemon initialization.  Creates and registers transport
 *      handle, and sets exports in the file EXPORTS.
 */
bool_t mountd_init()
{
    int sock;
    struct sockaddr_in addr;
    SVCXPRT *transp;

    addr.sin_family = AF_INET;
    addr.sin_port = htons(MOUNTPORT);
    addr.sin_addr.s_addr = INADDR_ANY;
    if ((sock = sock_create(SOCK_DGRAM, IPPROTO_UDP, &addr)) < 0) {
            (void) fprintf (stderr, "mountd: cannot get mount socket");
        sock_close(sock);
        return FALSE;
    }
    if ((transp = svcudp_create(sock, 0)) == (SVCXPRT *) NULL) {
        (void) fprintf (stderr, "mountd: cannot create udp handle");
        sock_close(sock);
        return FALSE;
    }
    if (! svc_register(transp, MOUNTPROG, MOUNTVERS, mountd_dispatch,
        IPPROTO_UDP)) {
        (void) fprintf(stderr, "mountd: cannot register transport\n");
        sock_close(sock);
        return FALSE;
    }
    if (! exps_parse()) {
        (void) fprintf(stderr, "mountd: cannot parse exports file\n");
        sock_close(sock);
        return FALSE;
    }

    return TRUE;
}

/*
 *  void mountd_dispatch(struct svc_req *req, SVCXPRT *xprt) --
 *      Dispatch routine for the mount daemon.
 */
void mountd_dispatch(req, xprt)
    struct svc_req *req;
    SVCXPRT *xprt;
{
#if DEBUG
static char *names[] = {"NULL", "MNT", "DUMP", "UMNT", "UMNTALL",
            "EXPORT", "EXPORTALL", "<invalid>"};
    DBGPRT1 (mountd, ">>> MOUNTPROC_%s", names[(req->rq_proc >
        MOUNTPROC_EXPORTALL) ? MOUNTPROC_EXPORTALL+1 : req->rq_proc]);
#endif

    switch((int) req->rq_proc) {

      case NULLPROC:            /* "ping" the mount daemon */
    if (! svc_sendreply(xprt, xdr_void, 0)) {
        (void) fprintf(stderr, "mountd: cannot send reply\n");
        return;
    }
    break;

      case MOUNTPROC_MNT:    mount(req, xprt);    break;
      case MOUNTPROC_UMNT:    unmount(req, xprt);    break;
      case MOUNTPROC_EXPORT:    expreply(req, xprt);    break;
      case MOUNTPROC_DUMP:
      case MOUNTPROC_UMNTALL:
      case MOUNTPROC_EXPORTALL:

      default:
    svcerr_noproc(xprt);
    }
}

/*
 *  void mount(struct svc_req *req, SVCXPRT *xprt) --
 *      Services a mount request
 */
void mount(req, xprt)
    struct svc_req *req;
    SVCXPRT *xprt;
{
    char *path = NULL, *hostname;
    struct fhstatus fhs;        /* file handle status */
    struct sockaddr_in addr;

    if (! svc_getargs(xprt, xdr_path, &path)) {
            DBGPRT0 (mountd, "cannot decode mount path");
        svcerr_decode(xprt);
        return;
    }
    DBGPRT1 (mountd, "path: %s", path);
    addr = *(svc_getcaller(xprt));
    if (! exps_isclnt(path, addr.sin_addr.s_addr)) {
            DBGPRT0 (mountd, "access denied");
        fhs.fhs_status = NFSERR_ACCES;
    }
    else if (! mntpntofh(path, &(fhs.fhs_fh))) {
            DBGPRT0 (mountd, "illegal path");
        fhs.fhs_status = (int) NFSERR_NOENT;
    }
    else
        fhs.fhs_status = (int) NFS_OK;

    /* reply to caller */
    if (! svc_sendreply(xprt, xdr_fhstatus, &fhs))
        (void) fprintf(stderr, "mount: cannot reply to mount req\n");

    svc_freeargs(xprt, xdr_path, &path);
}

/*
 *  void unmount(struct svc_req *req, SVCXPRT *xprt) --
 *      Unmount a filesystem.
 */
void unmount(req, xprt)
    struct svc_req *req;
    SVCXPRT *xprt;
{
    char *path = NULL;
    fhandle_t fh;

    if (! svc_getargs(xprt, xdr_path, &path)) {
            DBGPRT0 (mountd, "unmount: cannot decode");
        svcerr_decode(xprt);
        return;
    }
    DBGPRT1 (mountd, "unmounting %s", path);
    if (! mntpntofh(path, &fh))
        DBGPRT0 (mountd, "unmount: not in mount list");

    if (! svc_sendreply(xprt, xdr_void, NULL)) {
        (void) fprintf(stderr, "unmount: cannot send reply\n");
    }
    svc_freeargs(xprt, xdr_path, &path);
}

/*
 *  void expreply(struct svc_req *req, SVCXPRT *xprt) --
 *      Services an exports request
 */
void expreply(req, xprt)
     struct svc_req *req;
     SVCXPRT *xprt;
{
    struct exports *exp_list;

    exp_list = exps_get ();

    /* reply to caller */
    if (! svc_sendreply(xprt, xdr_exports, &exp_list))
      (void) fprintf(stderr, "mount: cannot reply to export req\n");
}

/*
 *  bool_t mntpntofh(char *path, fhandle_t *fhp) --
 *      Checks that path matches something in the export list and
 *      converts the path name to file status handle.
 */
bool_t mntpntofh(path, fhp)
    char *path;
    fhandle_t *fhp;
{
    Exports *ptr;

    if ((ptr = exps_isexport(path)) == NULL) {    /* not in list */
            DBGPRT1 (mountd, "path \"%s\" not in export list", path);
        return FALSE;
    }
    /* anything in export list should already be in directory tree cache */
    *fhp = pntofh (path);
    return TRUE;
}