afs.c

LFS.This is a kind of file system.

/* $Id: afs.C,v 1.2 2001/04/10 06:08:56 dm Exp $ */

/*
 *
 * Copyright (C) 2001 David Mazieres ([e-mail])
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2, or (at
 * your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 * USA
 *
 */

#include "cryptfs.h"

class aiddir : public afsdir {
  sfs_aid aid;
public:
  aiddir (afsdir *parent, sfs_aid a) : afsdir (parent), aid (a) {}
  void mkfattr3 (fattr3 *f, sfs_aid a);
  void nfs3_access (svccb *);
};

ref<afsroot> rootdir = afsroot::alloc ();
ref<afsdir> uiddir = rootdir->mkdir (UDNAME);

void
aiddir::mkfattr3 (fattr3 *f, sfs_aid a)
{
  afsdir::mkfattr3 (f, a);
  f->uid = a;
  f->mode = 0500;
}

void
aiddir::nfs3_access (svccb *sbp)
{
  if (sbp2aid (sbp) != aid && (!sbp->getaup () || sbp->getaup ()->aup_uid)) {
    access3res res (NFS3_OK);
    mkpoattr (res.resok->obj_attributes, sbp2aid (sbp));
    res.resok->access = 0;
    sbp->reply (&res);
  }
  else
    afsdir::nfs3_access (sbp);
}

void
afsroot::mkfattr3 (fattr3 *f, sfs_aid aid)
{
  /* BSD needs the seconds (not just milliseconds/nanoseconds) of the
   * mtime to change on every lookup/getattr in order to defeat the
   * name cache. */
  if (aid != lastaid) {
    lastaid = aid;
    bumpmtime ();
  }
  afsdir::mkfattr3 (f, aid);
}

afsnode *
afsroot::lookup (const str &name, sfs_aid aid)
{
  if (afsnode *e = afsdir::lookup (name, aid))
    return e;
  else if (ptr<afsdir> ud = utab[aid])
    return ud->lookup (name, aid);
  return NULL;
}

void
afsroot::nfs_remove (svccb *sbp)
{
  sfs_aid aid = sbp2aid (sbp);
  str name = sbp->vers () == 2
    ? str (sbp->template getarg<diropargs> ()->name)
    : str (sbp->template getarg<diropargs3> ()->name);
  if (!lookup (name, aid))
    nfs_error (sbp, NFSERR_NOENT);
  else if (name[0] == '.')
    nfs_error (sbp, NFSERR_ACCES);
  else if (!detach (aid, name))
    nfs_error (sbp, EBUSY);
  else if (sbp->vers () == 2)
    sbp->replyref (NFS_OK);
  else
    sbp->replyref (wccstat3 (NFS3_OK));
}

bool
afsroot::entryok (afsdirentry *de, sfs_aid aid)
{
  return de->dir == this || (de->dir && de->dir == utab[aid]);
}

afsdirentry *
afsroot::firstentry (sfs_aid aid)
{
  if (afsdirentry *de = afsdir::firstentry (aid))
    return de;
  if (ptr<afsdir> ud = utab[aid])
    return ud->firstentry (aid);
  return NULL;
}

afsdirentry *
afsroot::nextentry (afsdirentry *de, sfs_aid aid)
{
  if (de->dir != this)
    return de->dir->nextentry (de, aid);
  if ((de = afsdir::nextentry (de, aid)))
    return de;
  if (ptr<afsdir> ud = utab[aid])
    return ud->firstentry (aid);
  return NULL;
}

ptr<afslink>
afsroot::aidlink (sfs_aid aid, const str &contents, const str &name)
{
  ptr<afsdir> ud = utab[aid];
  if (!ud)
    utab.insert (aid, (ud = afsdir::alloc ()));
  bumpmtime ();			// XXX - unnecessary if failure, but who cares?
  return ud->symlink (contents, name);
}

bool
afsroot::aidunlink (sfs_aid aid, const str &name)
{
  ptr<afsdir> ud = utab[aid];
  if (ud && ud->unlink (name)) {
    if (!ud->firstentry (aid))
      utab.remove (aid);
    bumpmtime ();
    return true;
  }
  return false;
}

bool
uid_mkdir (sfs_aid aid, str name)
{
  str aidstr (strbuf () << aid);
  ptr<aiddir> ud;
  if (afsnode *d = uiddir->lookup (aidstr, aid)) {
    assert (d->type == NF3DIR);
    ud = mkref (static_cast<aiddir *> (d));
  }
  else{
    ud = New refcounted<aiddir> (uiddir, aid);
    uiddir->link (ud, aidstr);
  }
  if (!ud->mkdir (name))
    return false;
  rootdir->aidlink (aid, strbuf (UDNAME "/") << aidstr << "/" << name, name);
  return true;
}

void
uid_rmdir (sfs_aid aid, str name)
{
  str aidstr (strbuf () << aid);
  ptr<aiddir> ud;
  if (afsnode *d = uiddir->lookup (aidstr, aid)) {
    assert (d->type == NF3DIR);
    ud = mkref (static_cast<aiddir *> (d));
  }
  if (ud) {
    ud->unlink (name);
    if (!ud->firstentry (aid))
      uiddir->unlink (aidstr);
  }
  rootdir->aidunlink (aid, name);
}