proc.c

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	result = -ENOENT;
	if (!inode) {
		printk(KERN_ERR "smb_open: no inode for dentry %s/%s\n",
		       DENTRY_PATH(dentry));
		goto out;
	}

	if (!smb_is_open(inode)) {
		struct smb_sb_info *server = server_from_inode(inode);
		smb_lock_server(server);
		result = 0;
		if (!smb_is_open(inode))
			result = smb_proc_open(server, dentry, wish);
		smb_unlock_server(server);
		if (result) {
			PARANOIA("%s/%s open failed, result=%d\n",
				 DENTRY_PATH(dentry), result);
			goto out;
		}
		/*
		 * A successful open means the path is still valid ...
		 */
		smb_renew_times(dentry);
	}

	/*
	 * Check whether the access is compatible with the desired mode.
	 */
	result = 0;
	if (inode->u.smbfs_i.access != wish && 
	    inode->u.smbfs_i.access != SMB_O_RDWR)
	{
		PARANOIA("%s/%s access denied, access=%x, wish=%x\n",
			 DENTRY_PATH(dentry), inode->u.smbfs_i.access, wish);
		result = -EACCES;
	}
out:
	return result;
}

/* We're called with the server locked */

static int 
smb_proc_close(struct smb_sb_info *server, __u16 fileid, __u32 mtime)
{
	smb_setup_header(server, SMBclose, 3, 0);
	WSET(server->packet, smb_vwv0, fileid);
	DSET(server->packet, smb_vwv1, utc2local(server, mtime));
	return smb_request_ok(server, SMBclose, 0, 0);
}

/*
 * Called with the server locked.
 *
 * Win NT 4.0 has an apparent bug in that it fails to update the
 * modify time when writing to a file. As a workaround, we update
 * both modify and access time locally, and post the times to the
 * server when closing the file.
 */
static int 
smb_proc_close_inode(struct smb_sb_info *server, struct inode * ino)
{
	int result = 0;
	if (smb_is_open(ino))
	{
		/*
		 * We clear the open flag in advance, in case another
 		 * process observes the value while we block below.
		 */
		ino->u.smbfs_i.open = 0;

		/*
		 * Kludge alert: SMB timestamps are accurate only to
		 * two seconds ... round the times to avoid needless
		 * cache invalidations!
		 */
		if (ino->i_mtime & 1)
			ino->i_mtime--;
		if (ino->i_atime & 1)
			ino->i_atime--;
		/*
		 * If the file is open with write permissions,
		 * update the time stamps to sync mtime and atime.
		 */
		if ((server->opt.protocol >= SMB_PROTOCOL_LANMAN2) &&
		    !(ino->u.smbfs_i.access == SMB_O_RDONLY))
		{
			struct smb_fattr fattr;
			smb_get_inode_attr(ino, &fattr);
			smb_proc_setattr_ext(server, ino, &fattr);
		}

		result = smb_proc_close(server, ino->u.smbfs_i.fileid,
						ino->i_mtime);
		/*
		 * Force a revalidation after closing ... some servers
		 * don't post the size until the file has been closed.
		 */
		if (server->opt.protocol < SMB_PROTOCOL_NT1)
			ino->u.smbfs_i.oldmtime = 0;
		ino->u.smbfs_i.closed = jiffies;
	}
	return result;
}

int
smb_close(struct inode *ino)
{
	int result = 0;

	if (smb_is_open(ino)) {
		struct smb_sb_info *server = server_from_inode(ino);
		smb_lock_server(server);
		result = smb_proc_close_inode(server, ino);
		smb_unlock_server(server);
	}
	return result;
}

/*
 * This is used to close a file following a failed instantiate.
 * Since we don't have an inode, we can't use any of the above.
 */
int
smb_close_fileid(struct dentry *dentry, __u16 fileid)
{
	struct smb_sb_info *server = server_from_dentry(dentry);
	int result;

	smb_lock_server(server);
	result = smb_proc_close(server, fileid, CURRENT_TIME);
	smb_unlock_server(server);
	return result;
}

/* In smb_proc_read and smb_proc_write we do not retry, because the
   file-id would not be valid after a reconnection. */

int
smb_proc_read(struct inode *inode, off_t offset, int count, char *data)
{
	struct smb_sb_info *server = server_from_inode(inode);
	__u16 returned_count, data_len;
	unsigned char *buf;
	int result;

	smb_lock_server(server);
	smb_setup_header(server, SMBread, 5, 0);
	buf = server->packet;
	WSET(buf, smb_vwv0, inode->u.smbfs_i.fileid);
	WSET(buf, smb_vwv1, count);
	DSET(buf, smb_vwv2, offset);
	WSET(buf, smb_vwv4, 0);

	result = smb_request_ok(server, SMBread, 5, -1);
	if (result < 0)
		goto out;
	returned_count = WVAL(server->packet, smb_vwv0);

	buf = SMB_BUF(server->packet);
	data_len = WVAL(buf, 1);

	/* we can NOT simply trust the data_len given by the server ... */
	if (data_len > server->packet_size - (buf+3 - server->packet)) {
		printk(KERN_ERR "smb_proc_read: invalid data length!! "
		       "%d > %d - (%p - %p)\n",
		       data_len, server->packet_size, buf+3, server->packet);
		result = -EIO;
		goto out;
	}

	memcpy(data, buf+3, data_len);

	if (returned_count != data_len) {
		printk(KERN_NOTICE "smb_proc_read: returned != data_len\n");
		printk(KERN_NOTICE "smb_proc_read: ret_c=%d, data_len=%d\n",
		       returned_count, data_len);
	}
	result = data_len;

out:
	VERBOSE("ino=%ld, fileid=%d, count=%d, result=%d\n",
		inode->i_ino, inode->u.smbfs_i.fileid, count, result);
	smb_unlock_server(server);
	return result;
}

int
smb_proc_write(struct inode *inode, off_t offset, int count, const char *data)
{
	struct smb_sb_info *server = server_from_inode(inode);
	int result;
	__u8 *p;
	__u16 fileid = inode->u.smbfs_i.fileid;

	VERBOSE("ino=%ld, fileid=%d, count=%d@%ld, packet_size=%d\n",
		inode->i_ino, inode->u.smbfs_i.fileid, count, offset,
		server->packet_size);

	smb_lock_server(server);
	p = smb_setup_header(server, SMBwrite, 5, count + 3);
	WSET(server->packet, smb_vwv0, fileid);
	WSET(server->packet, smb_vwv1, count);
	DSET(server->packet, smb_vwv2, offset);
	WSET(server->packet, smb_vwv4, 0);

	*p++ = 1;
	WSET(p, 0, count);
	memcpy(p+2, data, count);

	result = smb_request_ok(server, SMBwrite, 1, 0);
	if (result >= 0)
		result = WVAL(server->packet, smb_vwv0);

	smb_unlock_server(server);
	return result;
}

int
smb_proc_create(struct dentry *dentry, __u16 attr, time_t ctime, __u16 *fileid)
{
	struct smb_sb_info *server = server_from_dentry(dentry);
	char *p;
	int result;

	smb_lock_server(server);

      retry:
	p = smb_setup_header(server, SMBcreate, 3, 0);
	WSET(server->packet, smb_vwv0, attr);
	DSET(server->packet, smb_vwv1, utc2local(server, ctime));
	result = smb_simple_encode_path(server, &p, dentry, NULL);
	if (result < 0)
		goto out;
	smb_setup_bcc(server, p);

	result = smb_request_ok(server, SMBcreate, 1, 0);
	if (result < 0) {
		if (smb_retry(server))
			goto retry;
		goto out;
	}
	*fileid = WVAL(server->packet, smb_vwv0);
	result = 0;

out:
	smb_unlock_server(server);
	return result;
}

int
smb_proc_mv(struct dentry *old_dentry, struct dentry *new_dentry)
{
	struct smb_sb_info *server = server_from_dentry(old_dentry);
	char *p;
	int result;

	smb_lock_server(server);

      retry:
	p = smb_setup_header(server, SMBmv, 1, 0);
	WSET(server->packet, smb_vwv0, aSYSTEM | aHIDDEN | aDIR);
	result = smb_simple_encode_path(server, &p, old_dentry, NULL);
	if (result < 0)
		goto out;
	result = smb_simple_encode_path(server, &p, new_dentry, NULL);
	if (result < 0)
		goto out;
	smb_setup_bcc(server, p);

	if ((result = smb_request_ok(server, SMBmv, 0, 0)) < 0) {
		if (smb_retry(server))
			goto retry;
		goto out;
	}
	result = 0;
out:
	smb_unlock_server(server);
	return result;
}

/*
 * Code common to mkdir and rmdir.
 */
static int
smb_proc_generic_command(struct dentry *dentry, __u8 command)
{
	struct smb_sb_info *server = server_from_dentry(dentry);
	char *p;
	int result;

	smb_lock_server(server);

      retry:
	p = smb_setup_header(server, command, 0, 0);
	result = smb_simple_encode_path(server, &p, dentry, NULL);
	if (result < 0)
		goto out;
	smb_setup_bcc(server, p);

	result = smb_request_ok(server, command, 0, 0);
	if (result < 0) {
		if (smb_retry(server))
			goto retry;
		goto out;
	}
	result = 0;
out:
	smb_unlock_server(server);
	return result;
}

int
smb_proc_mkdir(struct dentry *dentry)
{
	return smb_proc_generic_command(dentry, SMBmkdir);
}

int
smb_proc_rmdir(struct dentry *dentry)
{
	return smb_proc_generic_command(dentry, SMBrmdir);
}

#if SMBFS_POSIX_UNLINK
/*
 * Removes readonly attribute from a file. Used by unlink to give posix
 * semantics.
 * Note: called with the server locked.
 */
static int
smb_set_rw(struct dentry *dentry,struct smb_sb_info *server)
{
	int result;
	struct smb_fattr fattr;

	/* first get current attribute */
	result = smb_proc_do_getattr(server, dentry, &fattr);
	if (result < 0)
		return result;

	/* if RONLY attribute is set, remove it */
	if (fattr.attr & aRONLY) {  /* read only attribute is set */
		fattr.attr &= ~aRONLY;
		result = smb_proc_setattr_core(server, dentry, fattr.attr);
	}
	return result;
}
#endif

int
smb_proc_unlink(struct dentry *dentry)
{
	struct smb_sb_info *server = server_from_dentry(dentry);
	int flag = 0;
	char *p;
	int result;

	smb_lock_server(server);

      retry:
	p = smb_setup_header(server, SMBunlink, 1, 0);
	WSET(server->packet, smb_vwv0, aSYSTEM | aHIDDEN);
	result = smb_simple_encode_path(server, &p, dentry, NULL);
	if (result < 0)
		goto out;
	smb_setup_bcc(server, p);

	if ((result = smb_request_ok(server, SMBunlink, 0, 0)) < 0) {
#if SMBFS_POSIX_UNLINK
		if (result == -EACCES && !flag) {
			/* Posix semantics is for the read-only state
			   of a file to be ignored in unlink(). In the
			   SMB world a unlink() is refused on a
			   read-only file. To make things easier for
			   unix users we try to override the files
			   permission if the unlink fails with the
			   right error.
			   This introduces a race condition that could
			   lead to a file being written by someone who
			   shouldn't have access, but as far as I can
			   tell that is unavoidable */

			/* remove RONLY attribute and try again */
			result = smb_set_rw(dentry,server);
			if (result == 0) {
				flag = 1;
				goto retry;
			}
		}
#endif
		if (smb_retry(server))
			goto retry;
		goto out;
	}
	result = 0;
out:
	smb_unlock_server(server);
	return result;
}

/*
 * Called with the server locked
 */
int
smb_proc_flush(struct smb_sb_info *server, __u16 fileid)
{
	smb_setup_header(server, SMBflush, 1, 0);
	WSET(server->packet, smb_vwv0, fileid);
	return smb_request_ok(server, SMBflush, 0, 0);
}

int
smb_proc_trunc(struct smb_sb_info *server, __u16 fid, __u32 length)
{
	char *p;
	int result;

	smb_lock_server(server);

retry:
	p = smb_setup_header(server, SMBwrite, 5, 3);
	WSET(server->packet, smb_vwv0, fid);
	WSET(server->packet, smb_vwv1, 0);
	DSET(server->packet, smb_vwv2, length);
	WSET(server->packet, smb_vwv4, 0);
	*p++ = 1;
	WSET(p, 0, 0);

	if ((result = smb_request_ok(server, SMBwrite, 1, 0)) < 0) {
		if (smb_retry(server))
			goto retry;
		goto out;
	}

	/*
	 * win9x doesn't appear to update the size immediately.
	 * It will return the old file size after the truncate,
	 * confusing smbfs.
	 * NT and Samba return the new value immediately.
	 */
	if (server->mnt->flags & SMB_MOUNT_WIN95)
		smb_proc_flush(server, fid);
out:
	smb_unlock_server(server);
	return result;
}

static void
smb_init_dirent(struct smb_sb_info *server, struct smb_fattr *fattr)
{
	memset(fattr, 0, sizeof(*fattr));

	fattr->f_nlink = 1;
	fattr->f_uid = server->mnt->uid;
	fattr->f_gid = server->mnt->gid;
	fattr->f_blksize = SMB_ST_BLKSIZE;
}

static void
smb_finish_dirent(struct smb_sb_info *server, struct smb_fattr *fattr)
{
	fattr->f_mode = server->mnt->file_mode;
	if (fattr->attr & aDIR)
	{
		fattr->f_mode = server->mnt->dir_mode;
		fattr->f_size = SMB_ST_BLKSIZE;
	}
	/* Check the read-only flag */
	if (fattr->attr & aRONLY)
		fattr->f_mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH);

	/* How many 512 byte blocks do we need for this file? */
	fattr->f_blocks = 0;
	if (fattr->f_size != 0)
		fattr->f_blocks = 1 + ((fattr->f_size-1) >> 9);
	return;
}

void
smb_init_root_dirent(struct smb_sb_info *server, struct smb_fattr *fattr)
{
	smb_init_dirent(server, fattr);
	fattr->attr = aDIR;
	fattr->f_ino = 2; /* traditional root inode number */
	fattr->f_mtime = CURRENT_TIME;
	smb_finish_dirent(server, fattr);
}

/*
 * Decode a dirent for old protocols
 *
 * qname is filled with the decoded, and possibly translated, name.
 * fattr receives decoded attributes
 *
 * Bugs Noted:
 * (1) Pathworks servers may pad the name with extra spaces.
 */
static char *
smb_decode_short_dirent(struct smb_sb_info *server, char *p,
			struct qstr *qname, struct smb_fattr *fattr)
{
	int len;

	/*
	 * SMB doesn't have a concept of inode numbers ...
	 */
	smb_init_dirent(server, fattr);
	fattr->f_ino = 0;	/* FIXME: do we need this? */

	p += SMB_STATUS_SIZE;	/* reserved (search_status) */
	fattr->attr = *p;
	fattr->f_mtime = date_dos2unix(server, WVAL(p, 3), WVAL(p, 1));
	fattr->f_size = DVAL(p, 5);
	fattr->f_ctime = fattr->f_mtime;
	fattr->f_atime = fattr->f_mtime;
	qname->name = p + 9;
	len = strnlen(qname->name, 12);