proc.c

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	/*
	 * Trim trailing blanks for Pathworks servers
	 */
	while (len > 2 && qname->name[len-1] == ' ')
		len--;
	qname->len = len;

	smb_finish_dirent(server, fattr);

#if 0
	/* FIXME: These only work for ascii chars, and recent smbmount doesn't
	   allow the flag to be set anyway. It kills const. Remove? */
	switch (server->opt.case_handling) {
	case SMB_CASE_UPPER:
		str_upper(entry->name, len);
		break;
	case SMB_CASE_LOWER:
		str_lower(entry->name, len);
		break;
	default:
		break;
	}
#endif

	qname->len = server->convert(server->name_buf, SMB_MAXNAMELEN,
				     qname->name, len,
				     server->remote_nls, server->local_nls);
	qname->name = server->name_buf;

	DEBUG1("len=%d, name=%.*s\n", qname->len, qname->len, qname->name);
	return p + 22;
}

/*
 * This routine is used to read in directory entries from the network.
 * Note that it is for short directory name seeks, i.e.: protocol <
 * SMB_PROTOCOL_LANMAN2
 */
static int
smb_proc_readdir_short(struct file *filp, void *dirent, filldir_t filldir,
		       struct smb_cache_control *ctl)
{
	struct dentry *dir = filp->f_dentry;
	struct smb_sb_info *server = server_from_dentry(dir);
	struct qstr qname;
	struct smb_fattr fattr;
	char *p;
	int result;
	int i, first, entries_seen, entries;
	int entries_asked = (server->opt.max_xmit - 100) / SMB_DIRINFO_SIZE;
	__u16 bcc;
	__u16 count;
	char status[SMB_STATUS_SIZE];
	static struct qstr mask = { "*.*", 3, 0 };
	unsigned char *last_status;

	VERBOSE("%s/%s\n", DENTRY_PATH(dir));

	smb_lock_server(server);

	first = 1;
	entries = 0;
	entries_seen = 2; /* implicit . and .. */

	while (1) {
		p = smb_setup_header(server, SMBsearch, 2, 0);
		WSET(server->packet, smb_vwv0, entries_asked);
		WSET(server->packet, smb_vwv1, aDIR);
		if (first == 1) {
			result = smb_simple_encode_path(server, &p, dir, &mask);
			if (result < 0)
				goto unlock_return;
			if (p + 3 > (char*)server->packet+server->packet_size) {
				result = -ENAMETOOLONG;
				goto unlock_return;
			}
			*p++ = 5;
			WSET(p, 0, 0);
			p += 2;
			first = 0;
		} else {
			if (p + 5 + SMB_STATUS_SIZE >
			    (char*)server->packet + server->packet_size) {
				result = -ENAMETOOLONG;
				goto unlock_return;
			}
				
			*p++ = 4;
			*p++ = 0;
			*p++ = 5;
			WSET(p, 0, SMB_STATUS_SIZE);
			p += 2;
			memcpy(p, status, SMB_STATUS_SIZE);
			p += SMB_STATUS_SIZE;
		}

		smb_setup_bcc(server, p);

		result = smb_request_ok(server, SMBsearch, 1, -1);
		if (result < 0) {
			if ((server->rcls == ERRDOS) && 
			    (server->err  == ERRnofiles))
				break;
			if (smb_retry(server)) {
				ctl->idx = -1;	/* retry */
				result = 0;
			}
			goto unlock_return;
		}
		p = SMB_VWV(server->packet);
		count = WVAL(p, 0);
		if (count <= 0)
			break;

		result = -EIO;
		bcc = WVAL(p, 2);
		if (bcc != count * SMB_DIRINFO_SIZE + 3)
			goto unlock_return;
		p += 7;


		/* Make sure the response fits in the buffer. Fixed sized 
		   entries means we don't have to check in the decode loop. */

		last_status = SMB_BUF(server->packet) + 3 + (count - 1) *
			SMB_DIRINFO_SIZE;

		if (last_status + SMB_DIRINFO_SIZE >=
		    server->packet + server->packet_size) {
			printk(KERN_ERR "smb_proc_readdir_short: "
			       "last dir entry outside buffer! "
			       "%d@%p  %d@%p\n", SMB_DIRINFO_SIZE, last_status,
			       server->packet_size, server->packet);
			goto unlock_return;
		}

		/* Read the last entry into the status field. */
		memcpy(status, last_status, SMB_STATUS_SIZE);


		/* Now we are ready to parse smb directory entries. */

		for (i = 0; i < count; i++) {
			p = smb_decode_short_dirent(server, p, 
						    &qname, &fattr);

			if (entries_seen == 2 && qname.name[0] == '.') {
				if (qname.len == 1)
					continue;
				if (qname.name[1] == '.' && qname.len == 2)
					continue;
			}
			if (!smb_fill_cache(filp, dirent, filldir, ctl, 
					    &qname, &fattr))
				;	/* stop reading? */
			entries_seen++;
		}
	}
	result = entries;

unlock_return:
	smb_unlock_server(server);
	return result;
}

/*
 * Interpret a long filename structure using the specified info level:
 *   level 1 for anything below NT1 protocol
 *   level 260 for NT1 protocol
 *
 * qname is filled with the decoded, and possibly translated, name
 * fattr receives decoded attributes.
 *
 * Bugs Noted:
 * (1) Win NT 4.0 appends a null byte to names and counts it in the length!
 */
static char *
smb_decode_long_dirent(struct smb_sb_info *server, char *p, int level,
		       struct qstr *qname, struct smb_fattr *fattr)
{
	char *result;
	unsigned int len = 0;
	__u16 date, time;

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

	switch (level) {
	case 1:
		len = *((unsigned char *) p + 22);
		qname->name = p + 23;
		result = p + 24 + len;

		date = WVAL(p, 0);
		time = WVAL(p, 2);
		fattr->f_ctime = date_dos2unix(server, date, time);

		date = WVAL(p, 4);
		time = WVAL(p, 6);
		fattr->f_atime = date_dos2unix(server, date, time);

		date = WVAL(p, 8);
		time = WVAL(p, 10);
		fattr->f_mtime = date_dos2unix(server, date, time);
		fattr->f_size = DVAL(p, 12);
		/* ULONG allocation size */
		fattr->attr = WVAL(p, 20);

		VERBOSE("info 1 at %p, len=%d, name=%.*s\n",
			p, len, len, qname->name);
		break;
	case 260:
		result = p + WVAL(p, 0);
		len = DVAL(p, 60);
		if (len > 255) len = 255;
		/* NT4 null terminates */
		qname->name = p + 94;
		if (len && qname->name[len-1] == '\0')
			len--;

		fattr->f_ctime = smb_ntutc2unixutc(LVAL(p, 8));
		fattr->f_atime = smb_ntutc2unixutc(LVAL(p, 16));
		fattr->f_mtime = smb_ntutc2unixutc(LVAL(p, 24));
		/* change time (32) */
		fattr->f_size = DVAL(p, 40);
		/* alloc size (48) */
		fattr->attr = DVAL(p, 56);

		VERBOSE("info 260 at %p, len=%d, name=%.*s\n",
			p, len, len, qname->name);
		break;
	default:
		PARANOIA("Unknown info level %d\n", level);
		result = p + WVAL(p, 0);
		goto out;
	}

	smb_finish_dirent(server, fattr);

#if 0
	/* FIXME: These only work for ascii chars, and recent smbmount doesn't
	   allow the flag to be set anyway. Remove? */
	switch (server->opt.case_handling) {
	case SMB_CASE_UPPER:
		str_upper(qname->name, len);
		break;
	case SMB_CASE_LOWER:
		str_lower(qname->name, len);
		break;
	default:
		break;
	}
#endif

	qname->len = server->convert(server->name_buf, SMB_MAXNAMELEN,
				     qname->name, len,
				     server->remote_nls, server->local_nls);
	qname->name = server->name_buf;

out:
	return result;
}

/* findfirst/findnext flags */
#define SMB_CLOSE_AFTER_FIRST (1<<0)
#define SMB_CLOSE_IF_END (1<<1)
#define SMB_REQUIRE_RESUME_KEY (1<<2)
#define SMB_CONTINUE_BIT (1<<3)

/*
 * Note: samba-2.0.7 (at least) has a very similar routine, cli_list, in
 * source/libsmb/clilist.c. When looking for smb bugs in the readdir code,
 * go there for advise.
 *
 * Bugs Noted:
 * (1) When using Info Level 1 Win NT 4.0 truncates directory listings 
 * for certain patterns of names and/or lengths. The breakage pattern
 * is completely reproducible and can be toggled by the creation of a
 * single file. (E.g. echo hi >foo breaks, rm -f foo works.)
 */
static int
smb_proc_readdir_long(struct file *filp, void *dirent, filldir_t filldir,
		      struct smb_cache_control *ctl)
{
	struct dentry *dir = filp->f_dentry;
	struct smb_sb_info *server = server_from_dentry(dir);
	struct qstr qname;
	struct smb_fattr fattr;

	unsigned char *p, *lastname;
	char *mask, *param = server->temp_buf;
	__u16 command;
	int first, entries_seen;

	/* Both NT and OS/2 accept info level 1 (but see note below). */
	int info_level = 260;
	const int max_matches = 512;

	unsigned char *resp_data = NULL;
	unsigned char *resp_param = NULL;
	int resp_data_len = 0;
	int resp_param_len = 0;
	int ff_searchcount = 0;
	int ff_eos = 0;
	int ff_lastname = 0;
	int ff_dir_handle = 0;
	int loop_count = 0;
	int mask_len, i, result;
	static struct qstr star = { "*", 1, 0 };

	/*
	 * use info level 1 for older servers that don't do 260
	 */
	if (server->opt.protocol < SMB_PROTOCOL_NT1)
		info_level = 1;

	smb_lock_server(server);

	/*
	 * Encode the initial path
	 */
	mask = param + 12;

	mask_len = smb_encode_path(server, mask, SMB_MAXNAMELEN+1, dir, &star);
	if (mask_len < 0) {
		result = mask_len;
		goto unlock_return;
	}
	mask_len--;	/* mask_len is strlen, not #bytes */
	first = 1;
	VERBOSE("starting mask_len=%d, mask=%s\n", mask_len, mask);

	result = 0;
	entries_seen = 2;
	ff_eos = 0;

	while (ff_eos == 0) {
		loop_count += 1;
		if (loop_count > 10) {
			printk(KERN_WARNING "smb_proc_readdir_long: "
			       "Looping in FIND_NEXT??\n");
			result = -EIO;
			break;
		}

		if (first != 0) {
			command = TRANSACT2_FINDFIRST;
			WSET(param, 0, aSYSTEM | aHIDDEN | aDIR);
			WSET(param, 2, max_matches);	/* max count */
			WSET(param, 4, SMB_CLOSE_IF_END);
			WSET(param, 6, info_level);
			DSET(param, 8, 0);
		} else {
			command = TRANSACT2_FINDNEXT;

			VERBOSE("handle=0x%X, lastname=%d, mask=%s\n",
				ff_dir_handle, ff_lastname, mask);

			WSET(param, 0, ff_dir_handle);	/* search handle */
			WSET(param, 2, max_matches);	/* max count */
			WSET(param, 4, info_level);
			DSET(param, 6, 0);
			WSET(param, 10, SMB_CONTINUE_BIT|SMB_CLOSE_IF_END);
		}

		result = smb_trans2_request(server, command,
					    0, NULL, 12 + mask_len + 1, param,
					    &resp_data_len, &resp_data,
					    &resp_param_len, &resp_param);

		if (result < 0) {
			if (smb_retry(server)) {
				PARANOIA("error=%d, retrying\n", result);
				ctl->idx = -1;	/* retry */
				result = 0;
				goto unlock_return;
			}
			PARANOIA("error=%d, breaking\n", result);
			break;
		}

		if (server->rcls == ERRSRV && server->err == ERRerror) {
			/* a damn Win95 bug - sometimes it clags if you 
			   ask it too fast */
			current->state = TASK_INTERRUPTIBLE;
			schedule_timeout(HZ/5);
			continue;
                }

		if (server->rcls != 0) {
			result = smb_errno(server);
			PARANOIA("name=%s, result=%d, rcls=%d, err=%d\n",
				 mask, result, server->rcls, server->err);
			break;
		}

		/* parse out some important return info */
		if (first != 0) {
			ff_dir_handle = WVAL(resp_param, 0);
			ff_searchcount = WVAL(resp_param, 2);
			ff_eos = WVAL(resp_param, 4);
			ff_lastname = WVAL(resp_param, 8);
		} else {
			ff_searchcount = WVAL(resp_param, 0);
			ff_eos = WVAL(resp_param, 2);
			ff_lastname = WVAL(resp_param, 6);
		}

		if (ff_searchcount == 0)
			break;

		/*
		 * We might need the lastname for continuations.
		 *
		 * Note that some servers (win95?) point to the filename and
		 * others (NT4, Samba using NT1) to the dir entry. We assume
		 * here that those who do not point to a filename do not need
		 * this info to continue the listing.
		 *
		 * OS/2 needs this and talks infolevel 1
		 * NetApps want lastname with infolevel 260
		 *
		 * Both are happy if we return the data they point to. So we do.
		 */
		mask_len = 0;
		if (ff_lastname > 0 && ff_lastname < resp_data_len) {
			lastname = resp_data + ff_lastname;

			switch (info_level) {
			case 260:
				mask_len = resp_data_len - ff_lastname;
				break;
			case 1:
				/* lastname points to a length byte */
				mask_len = *lastname++;
				if (ff_lastname + 1 + mask_len > resp_data_len)
					mask_len = resp_data_len - ff_lastname - 1;
				break;
			}

			/*
			 * Update the mask string for the next message.
			 */
			if (mask_len < 0)
				mask_len = 0;
			if (mask_len > 255)
				mask_len = 255;
			if (mask_len)
				strncpy(mask, lastname, mask_len);
		}
		mask_len = strnlen(mask, mask_len);
		VERBOSE("new mask, len=%d@%d of %d, mask=%.*s\n",
			mask_len, ff_lastname, resp_data_len, mask_len, mask);

		/* Now we are ready to parse smb directory entries. */

		/* point to the data bytes */
		p = resp_data;
		for (i = 0; i < ff_searchcount; i++) {
			/* make sure we stay within the buffer */
			if (p >= resp_data + resp_data_len) {
				printk(KERN_ERR "smb_proc_readdir_long: "
				       "dirent pointer outside buffer! "
				       "%p  %d@%p  %d@%p\n",
				       p, resp_data_len, resp_data,
				       server->packet_size, server->packet);
				result = -EIO; /* always a comm. error? */
				goto unlock_return;
			}

			p = smb_decode_long_dirent(server, p, info_level,
						   &qname, &fattr);

			/* ignore . and .. from the server */
			if (entries_seen == 2 && qname.name[0] == '.') {
				if (qname.len == 1)
					continue;
				if (qname.name[1] == '.' && qname.len == 2)
					continue;
			}

			if (!smb_fill_cache(filp, dirent, filldir, ctl, 
					    &qname, &fattr))
				;	/* stop reading? */
			entries_seen++;
		}

		VERBOSE("received %d entries, eos=%d\n", ff_searchcount,ff_eos);

		first = 0;
		loop_count = 0;
	}

unlock_return:
	smb_unlock_server(server);
	return result;
}

int
smb_proc_readdir(struct file *filp, void *dirent, filldir_t filldir,
		 struct smb_cache_control *ctl)
{
	struct smb_sb_info *server = server_from_dentry(filp->f_dentry);

	if (server->opt.protocol >= SMB_PROTOCOL_LANMAN2)
		return smb_proc_readdir_long(filp, dirent, filldir, ctl);
	else
		return smb_proc_readdir_short(filp, dirent, filldir, ctl);
}

/*
 * This version uses the trans2 TRANSACT2_FINDFIRST message 
 * to get the attribute data.
 * Note: called with the server locked.
 *
 * Bugs Noted: