/* ops.c NFS daemon protocol operations.

   Copyright (C) 1996, 2001, 2002, 2007 Free Software Foundation, Inc.

   Written by Michael I. Bushnell, p/BSG.

   This file is part of the GNU Hurd.

   The GNU Hurd 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.

   The GNU Hurd 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, USA. */

#include <hurd/io.h>
#include <hurd/fs.h>
#include <fcntl.h>
#include <hurd/paths.h>
#include <hurd.h>
#include <dirent.h>
#include <string.h>
#include <sys/mman.h>

#include "nfsd.h"
#include "../nfs/mount.h" /* XXX */
#include <rpc/pmap_prot.h>

static error_t
op_null (struct cache_handle *c,
	 int *p,
	 int **reply,
	 int version)
{
  return 0;
}

static error_t
op_getattr (struct cache_handle *c,
	    int *p,
	    int **reply,
	    int version)
{
  struct stat st;
  error_t err;

  err = io_stat (c->port, &st);
  if (!err)
    *reply = encode_fattr (*reply, &st, version);
  return err;
}

static error_t
complete_setattr (mach_port_t port,
		  int *p)
{
  uid_t uid, gid;
  off_t size;
  time_value_t atime, mtime;
  struct stat st;
  error_t err;

  err = io_stat (port, &st);
  if (err)
    return err;

  uid = ntohl (*p);
  p++;
  gid = ntohl (*p);
  p++;
  if (uid == -1)
    uid = st.st_uid;
  if (gid == -1)
    gid = st.st_gid;
  if (uid != st.st_uid || gid != st.st_gid)
    err = file_chown (port, uid, gid);
  if (err)
    return err;

  size = ntohl (*p);
  p++;
  if (size != -1 && size != st.st_size)
    err = file_set_size (port, size);
  if (err)
    return err;

  atime.seconds = ntohl (*p);
  p++;
  atime.microseconds = ntohl (*p);
  p++;
  mtime.seconds = ntohl (*p);
  p++;
  mtime.microseconds = ntohl (*p);
  p++;

  if (atime.seconds != -1 && atime.microseconds == -1)
    atime.microseconds = 0;
  if (mtime.seconds != -1 && mtime.microseconds == -1)
    mtime.microseconds = 0;

  if (atime.seconds == -1)
    atime.seconds = st.st_atim.tv_sec;
  if (atime.microseconds == -1)
    atime.microseconds = st.st_atim.tv_nsec / 1000;
  if (mtime.seconds == -1)
    mtime.seconds = st.st_mtim.tv_sec;
  if (mtime.microseconds == -1)
    mtime.microseconds = st.st_mtim.tv_nsec / 1000;

  if (atime.seconds != st.st_atim.tv_sec
      || atime.microseconds != st.st_atim.tv_nsec / 1000
      || mtime.seconds != st.st_mtim.tv_sec
      || mtime.microseconds != st.st_mtim.tv_nsec / 1000)
    err = file_utimes (port, atime, mtime);

  return err;
}

static error_t
op_setattr (struct cache_handle *c,
	    int *p,
	    int **reply,
	    int version)
{
  error_t err = 0;
  mode_t mode;
  struct stat st;

  mode = ntohl (*p);
  p++;
  if (mode != -1)
    err = file_chmod (c->port, mode);

  if (!err)
    err = complete_setattr (c->port, p);
  if (!err)
    err = io_stat (c->port, &st);
  if (err)
    return err;

  *reply = encode_fattr (*reply, &st, version);
  return 0;
}

static error_t
op_lookup (struct cache_handle *c,
	   int *p,
	   int **reply,
	   int version)
{
  error_t err;
  char *name;
  retry_type do_retry;
  char retry_name [1024];
  mach_port_t newport;
  struct cache_handle *newc;
  struct stat st;

  decode_name (p, &name);

  err = dir_lookup (c->port, name, O_NOTRANS, 0, &do_retry, retry_name,
		    &newport);
  free (name);

  /* Block attempts to bounce out of this filesystem by any technique.  */
  if (!err
      && (do_retry != FS_RETRY_NORMAL
	  || retry_name[0] != '\0'))
    err = EACCES;

  if (!err)
    err = io_stat (newport, &st);

  if (err)
    return err;

  newc = create_cached_handle (*(int *)c->handle, c, newport);
  if (!newc)
    return ESTALE;
  *reply = encode_fhandle (*reply, newc->handle);
  *reply = encode_fattr (*reply, &st, version);
  return 0;
}

static error_t
op_readlink (struct cache_handle *c,
	     int *p,
	     int **reply,
	     int version)
{
  char buf[2048], *transp = buf;
  mach_msg_type_number_t len = sizeof (buf);
  error_t err;

  /* Shamelessly copied from the libc readlink.  */
  err = file_get_translator (c->port, &transp, &len);
  if (err)
    {
      if (transp != buf)
	munmap (transp, len);
      return err;
    }

  if (len < sizeof (_HURD_SYMLINK)
      || memcmp (transp, _HURD_SYMLINK, sizeof (_HURD_SYMLINK)))
    return EINVAL;

  transp += sizeof (_HURD_SYMLINK);

  *reply = encode_string (*reply, transp);

  if (transp != buf)
    munmap (transp, len);

  return 0;
}

static size_t
count_read_buffersize (int *p, int version)
{
  p++;			/* Skip OFFSET.  */
  return ntohl (*p);	/* Return COUNT.  */
}

static error_t
op_read (struct cache_handle *c,
	 int *p,
	 int **reply,
	 int version)
{
  off_t offset;
  size_t count;
  char buf[2048], *bp = buf;
  mach_msg_type_number_t buflen = sizeof (buf);
  struct stat st;
  error_t err;

  offset = ntohl (*p);
  p++;
  count = ntohl (*p);
  p++;

  err = io_read (c->port, &bp, &buflen, offset, count);
  if (err)
    {
      if (bp != buf)
	munmap (bp, buflen);
      return err;
    }

  err = io_stat (c->port, &st);
  if (err)
    return err;

  *reply = encode_fattr (*reply, &st, version);
  *reply = encode_data (*reply, bp, buflen);

  if (bp != buf)
    munmap (bp, buflen);

  return 0;
}

static error_t
op_write (struct cache_handle *c,
	  int *p,
	  int **reply,
	  int version)
{
  off_t offset;
  size_t count;
  error_t err;
  mach_msg_type_number_t amt;
  char *bp;
  struct stat st;

  p++;
  offset = ntohl (*p);
  p++;
  p++;
  count = ntohl (*p);
  p++;
  bp = (char *) *reply;

  while (count)
    {
      err = io_write (c->port, bp, count, offset, &amt);
      if (err)
	return err;
      if (amt == 0)
	return EIO;
      count -= amt;
      bp += amt;
      offset += amt;
    }

  file_sync (c->port, 1, 0);

  err = io_stat (c->port, &st);
  if (err)
    return err;
  *reply = encode_fattr (*reply, &st, version);
  return 0;
}

static error_t
op_create (struct cache_handle *c,
	   int *p,
	   int **reply,
	   int version)
{
  error_t err;
  char *name;
  retry_type do_retry;
  char retry_name [1024];
  mach_port_t newport;
  struct cache_handle *newc;
  struct stat st;
  mode_t mode;
  int statchanged = 0;
  off_t size;

  p = decode_name (p, &name);
  mode = ntohl (*p);
  p++;

  err = dir_lookup (c->port, name, O_NOTRANS | O_CREAT | O_TRUNC, mode,
		    &do_retry, retry_name, &newport);
  if (!err
      && (do_retry != FS_RETRY_NORMAL
	  || retry_name[0] != '\0'))
    err = EACCES;

  if (err)
    return err;

  if (!err)
    err = io_stat (newport, &st);
  if (err)
    goto errout;

  /* NetBSD ignores most of the setattr fields given; that's good enough
     for me too.  */

  p++, p++;			/* Skip uid and gid.  */

  size = ntohl (*p);
  p++;
  if (size != -1 && size != st.st_size)
    {
      err = file_set_size (newport, size);
      statchanged = 1;
    }
  if (err)
    goto errout;

  /* Ignore times.  */

  if (statchanged)
    err = io_stat (newport, &st);

  if (err)
    {
    errout:
      dir_unlink (c->port, name);
      free (name);
      return err;
    }
  free (name);

  newc = create_cached_handle (*(int *)c->handle, c, newport);
  if (!newc)
    return ESTALE;

  *reply = encode_fhandle (*reply, newc->handle);
  *reply = encode_fattr (*reply, &st, version);
  return 0;
}

static error_t
op_remove (struct cache_handle *c,
	   int *p,
	   int **reply,
	   int version)
{
  error_t err;
  char *name;

  decode_name (p, &name);

  err = dir_unlink (c->port, name);
  free (name);

  return err;
}

static error_t
op_rename (struct cache_handle *fromc,
	   int *p,
	   int **reply,
	   int version)
{
  struct cache_handle *toc;
  char *fromname, *toname;
  error_t err = 0;

  p = decode_name (p, &fromname);
  p = lookup_cache_handle (p, &toc, fromc->ids);
  decode_name (p, &toname);

  if (!toc)
    err = ESTALE;
  if (!err)
    err = dir_rename (fromc->port, fromname, toc->port, toname, 0);
  free (fromname);
  free (toname);
  return err;
}

static error_t
op_link (struct cache_handle *filec,
	 int *p,
	 int **reply,
	 int version)
{
  struct cache_handle *dirc;
  char *name;
  error_t err = 0;

  p = lookup_cache_handle (p, &dirc, filec->ids);
  decode_name (p, &name);

  if (!dirc)
    err = ESTALE;
  if (!err)
    err = dir_link (dirc->port, filec->port, name, 1);

  free (name);
  return err;
}

static error_t
op_symlink (struct cache_handle *c,
	    int *p,
	    int **reply,
	    int version)
{
  char *name, *target;
  error_t err;
  mode_t mode;
  file_t newport = MACH_PORT_NULL;
  size_t len;
  char *buf;

  p = decode_name (p, &name);
  p = decode_name (p, &target);
  mode = ntohl (*p);
  p++;
  if (mode == -1)
    mode = 0777;

  len = strlen (target) + 1;
  buf = alloca (sizeof (_HURD_SYMLINK) + len);
  memcpy (buf, _HURD_SYMLINK, sizeof (_HURD_SYMLINK));
  memcpy (buf + sizeof (_HURD_SYMLINK), target, len);

  err = dir_mkfile (c->port, O_WRITE, mode, &newport);
  if (!err)
    err = file_set_translator (newport,
			       FS_TRANS_EXCL|FS_TRANS_SET,
			       FS_TRANS_EXCL|FS_TRANS_SET, 0,
			       buf, sizeof (_HURD_SYMLINK) + len,
			       MACH_PORT_NULL, MACH_MSG_TYPE_COPY_SEND);
  if (!err)
    err = dir_link (c->port, newport, name, 1);

  free (name);
  free (target);

  if (newport != MACH_PORT_NULL)
    mach_port_deallocate (mach_task_self (), newport);
  return err;
}

static error_t
op_mkdir (struct cache_handle *c,
	  int *p,
	  int **reply,
	  int version)
{
  char *name;
  mode_t mode;
  retry_type do_retry;
  char retry_name [1024];
  mach_port_t newport;
  struct stat st;
  struct cache_handle *newc;
  error_t err;

  p = decode_name (p, &name);
  mode = ntohl (*p);
  p++;

  err = dir_mkdir (c->port, name, mode);

  if (err)
    {
      free (name);
      return err;
    }

  err = dir_lookup (c->port, name, O_NOTRANS, 0, &do_retry,
		    retry_name, &newport);
  free (name);
  if (!err
      && (do_retry != FS_RETRY_NORMAL
	  || retry_name[0] != '\0'))
    err = EACCES;
  if (err)
    return err;

  /* Ignore the rest of the sattr structure.  */

  if (!err)
    err = io_stat (newport, &st);
  if (err)
    return err;

  newc = create_cached_handle (*(int *)c->handle, c, newport);
  if (!newc)
    return ESTALE;
  *reply = encode_fhandle (*reply, newc->handle);
  *reply = encode_fattr (*reply, &st, version);
  return 0;
}

static error_t
op_rmdir (struct cache_handle *c,
	  int *p,
	  int **reply,
	  int version)
{
  char *name;
  error_t err;

  decode_name (p, &name);

  err = dir_rmdir (c->port, name);
  free (name);
  return err;
}

static error_t
op_readdir (struct cache_handle *c,
	    int *p,
	    int **reply,
	    int version)
{
  int cookie;
  unsigned count;
  error_t err;
  char *buf;
  struct dirent *dp;
  size_t bufsize;
  int nentries;
  int i;
  int *replystart;
  int *r;

  cookie = ntohl (*p);
  p++;
  count = ntohl (*p);
  p++;

  buf = (char *) 0;
  bufsize = 0;
  err = dir_readdir (c->port, &buf, &bufsize, cookie, -1, count, &nentries);
  if (err)
    {
      if (buf)
	munmap (buf, bufsize);
      return err;
    }

  r = *reply;

  if (nentries == 0)
    {
      *(r++) = htonl (0);	/* No entry.  */
      *(r++) = htonl (1);	/* EOF.  */
    }
  else
    {
      for (i = 0, dp = (struct dirent *) buf, replystart = *reply;
	   ((char *)dp < buf + bufsize
	    && i < nentries
	    && (char *)reply < (char *)replystart + count);
	   i++, dp = (struct dirent *) ((char *)dp + dp->d_reclen))
	{
	  *(r++) = htonl (1);			/* Entry present.  */
	  *(r++) = htonl (dp->d_ino);
	  r = encode_string (r, dp->d_name);
	  *(r++) = htonl (i + cookie + 1);	/* Next entry.  */
	}
      *(r++) = htonl (0);			/* No more entries.  */
      *(r++) = htonl (0);			/* Not EOF.  */
    }

  *reply = r;

  if (buf)
    munmap (buf, bufsize);

  return 0;
}

static size_t
count_readdir_buffersize (int *p, int version)
{
  p++;			/* Skip COOKIE.  */
  return ntohl (*p);	/* Return COUNT.  */
}

static error_t
op_statfs (struct cache_handle *c,
	   int *p,
	   int **reply,
	   int version)
{
  struct statfs st;
  error_t err;

  err = file_statfs (c->port, &st);
  if (!err)
    *reply = encode_statfs (*reply, &st);
  return err;
}

static error_t
op_mnt (struct cache_handle *c,
	int *p,
	int **reply,
	int version)
{
  file_t root;
  struct cache_handle *newc;
  char *name;

  decode_name (p, &name);

  root = file_name_lookup (name, 0, 0);
  if (!root)
    {
      free (name);
      return errno;
    }

  newc = create_cached_handle (enter_filesystem (name, root), c, root);
  free (name);
  if (!newc)
    return ESTALE;
  *reply = encode_fhandle (*reply, newc->handle);
  return 0;
}

static error_t
op_getport (struct cache_handle *c,
	    int *p,
	    int **reply,
	    int version)
{
  int prog, vers, prot;

  prog = ntohl (*p);
  p++;
  vers = ntohl (*p);
  p++;
  prot = ntohl (*p);
  p++;

  if (prot != IPPROTO_UDP)
    *(*reply)++ = htonl (0);
  else if ((prog == MOUNTPROG && vers == MOUNTVERS)
	   || (prog == NFS_PROGRAM && vers == NFS_VERSION))
    *(*reply)++ = htonl (NFS_PORT);
  else if (prog == PMAPPROG && vers == PMAPVERS)
    *(*reply)++ = htonl (PMAPPORT);
  else
    *(*reply)++ = 0;

  return 0;
}


struct proctable nfs2table =
{
  NFS2PROC_NULL,		/* First proc.  */
  NFS2PROC_STATFS,		/* Last proc.  */
  {
    { op_null, 0, 0, 0},
    { op_getattr, 0, 1, 1},
    { op_setattr, 0, 1, 1},
    { 0, 0, 0, 0 },		/* Deprecated NFSPROC_ROOT.  */
    { op_lookup, 0, 1, 1},
    { op_readlink, 0, 1, 1},
    { op_read, count_read_buffersize, 1, 1},
    { 0, 0, 0, 0 },		/* Nonexistent NFSPROC_WRITECACHE.  */
    { op_write, 0, 1, 1},
    { op_create, 0, 1, 1},
    { op_remove, 0, 1, 1},
    { op_rename, 0, 1, 1},
    { op_link, 0, 1, 1},
    { op_symlink, 0, 1, 1},
    { op_mkdir, 0, 1, 1},
    { op_rmdir, 0, 1, 1},
    { op_readdir, count_readdir_buffersize, 1, 1},
    { op_statfs, 0, 1, 1},
  }
};


struct proctable mounttable =
{
  MOUNTPROC_NULL,		/* First proc.  */
  MOUNTPROC_EXPORT,		/* Last proc.  */
  {
    { op_null, 0, 0, 0},
    { op_mnt, 0, 0, 1},
    { 0, 0, 0, 0},		/* MOUNTPROC_DUMP */
    { op_null, 0, 0, 0},	/* MOUNTPROC_UMNT */
    { op_null, 0, 0, 0},	/* MOUNTPROC_UMNTALL */
    { 0, 0, 0, 0},		/* MOUNTPROC_EXPORT */
  }
};

struct proctable pmaptable =
{
  PMAPPROC_NULL,		/* First proc.  */
  PMAPPROC_CALLIT,		/* Last proc.  */
  {
    { op_null, 0, 0, 0},
    { 0, 0, 0, 0},		/* PMAPPROC_SET */
    { 0, 0, 0, 0},		/* PMAPPROC_UNSET */
    { op_getport, 0, 0, 0},
    { 0, 0, 0, 0},		/* PMAPPROC_DUMP */
    { 0, 0, 0, 0},		/* PMAPPROC_CALLIT */
  }
};