directory.c File Reference

#include <assert.h>
#include <errno.h>
#include <grp.h>
#include <pwd.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <utime.h>
#include <bstrlib.h>
#include <atalk/adouble.h>
#include <atalk/afp.h>
#include <atalk/cnid.h>
#include <atalk/errchk.h>
#include <atalk/fce_api.h>
#include <atalk/globals.h>
#include <atalk/logger.h>
#include <atalk/netatalk_conf.h>
#include <atalk/unix.h>
#include <atalk/util.h>
#include <atalk/uuid.h>
#include <atalk/vfs.h>
#include "desktop.h"
#include "dircache.h"
#include "directory.h"
#include "file.h"
#include "filedir.h"
#include "fork.h"
#include "hash.h"
#include "mangle.h"
#include "unix.h"
#include "volume.h"

Macros
#define	DIRLOOKUP_LOG_FMT   "dirlookup_internal(did:%u)"

Functions
static int	netatalk_mkdir (const struct vol *vol, const char *name)
static int	deletedir (const struct vol *vol, int dirfd, char *dir)
static int	copydir (struct vol *vol, struct dir *ddir, int dirfd, char *src, char *dst)
static int	diroffcnt (struct dir *dir, struct stat *st)
static int	invisible_dots (const struct vol *vol, const char *name)
static int	set_dir_errors (struct path *path, const char *where, int err)
static int	cname_mtouname (const struct vol *vol, struct dir *dir, struct path *ret, int toUTF8)
	Convert name in client encoding to server encoding.
static struct path *	path_from_dir (struct vol *vol, struct dir *dir, struct path *ret)
	Build struct path from struct dir.
int	get_afp_errno (const int param)
static struct dir *	dirlookup_internal (const struct vol *vol, cnid_t did, int retry, int strict)
	Internal CNID (Directory ID) resolution with retry control.
static struct dir *	dirlookup_internal_retry (const struct vol *vol, cnid_t did, int strict, bstring *fullpath_ptr, char **upath_ptr)
	Retry helper for dirlookup_internal on ENOENT.
struct dir *	dirlookup (const struct vol *vol, cnid_t did)
	Public CNID (Directory ID) resolution (supports files and directories).
struct dir *	dirlookup_strict (const struct vol *vol, cnid_t did)
	Strict DID resolution with inode validation.
struct dir *	dir_new (const char *m_name, const char *u_name, const struct vol *vol, cnid_t pdid, cnid_t did, bstring path, struct stat *st)
	Construct struct dir.
void	dir_free (struct dir *dir)
	Free a struct dir and all its members.
struct dir *	dir_add (struct vol *vol, const struct dir *dir, struct path *path, int len)
	Create struct dir from struct path.
void	dir_free_invalid_q (void)
	Free the queue with invalid struct dirs.
int	dir_remove (const struct vol *vol, struct dir *dir)
	Remove a file/directory from dircache with automatic curdir recovery.
struct path *	cname (struct vol *vol, struct dir *dir, char **cpath)
	Resolve a catalog node name path.
int	movecwd (const struct vol *vol, struct dir *dir)
	chdir() to dir
int	check_access (const AFPObj *obj, struct vol *vol, char *path, int mode)
int	file_access (const AFPObj *obj, struct vol *vol, struct path *path, int mode)
void	setdiroffcnt (struct dir *dir, struct stat *st, uint32_t count)
int	dirreenumerate (struct dir *dir, struct stat *st)
int	getdirparams (const AFPObj *obj, const struct vol *vol, uint16_t bitmap, struct path *s_path, struct dir *dir, char *buf, size_t *buflen)
int	path_error (struct path *path, int error)
int	afp_setdirparams (AFPObj *obj, char *ibuf, size_t ibuflen, char *rbuf, size_t *rbuflen)
int	setdirparams (struct vol *vol, struct path *path, uint16_t d_bitmap, char *buf)
int	afp_syncdir (AFPObj *obj, char *ibuf, size_t ibuflen, char *rbuf, size_t *rbuflen)
int	afp_createdir (AFPObj *obj, char *ibuf, size_t ibuflen, char *rbuf, size_t *rbuflen)
int	renamedir (struct vol *vol, int dirfd, char *src, char *dst, struct dir *newparent, char *newname)
	Rename a directory.
int	deletecurdir (struct vol *vol)
int	afp_mapid (AFPObj *obj, char *ibuf, size_t ibuflen, char *rbuf, size_t *rbuflen)
int	afp_mapname (AFPObj *obj, char *ibuf, size_t ibuflen, char *rbuf, size_t *rbuflen)
int	afp_closedir (AFPObj *obj, char *ibuf, size_t ibuflen, char *rbuf, size_t *rbuflen)
int	afp_opendir (AFPObj *obj, char *ibuf, size_t ibuflen, char *rbuf, size_t *rbuflen)

Variables
int	afp_errno
struct dir	rootParent
struct dir *	curdir = &rootParent
struct path	Cur_Path
q_t *	invalid_dircache_entries

Macro Definition Documentation

DIRLOOKUP_LOG_FMT

#define DIRLOOKUP_LOG_FMT   "dirlookup_internal(did:%u)"

Function Documentation

afp_closedir()

int afp_closedir	(	AFPObj *	obj,
		char *	ibuf,
		size_t	ibuflen,
		char *	rbuf,
		size_t *	rbuflen )

afp_createdir()

int afp_createdir	(	AFPObj *	obj,
		char *	ibuf,
		size_t	ibuflen,
		char *	rbuf,
		size_t *	rbuflen )

afp_mapid()

int afp_mapid	(	AFPObj *	obj,
		char *	ibuf,
		size_t	ibuflen,
		char *	rbuf,
		size_t *	rbuflen )

afp_mapname()

int afp_mapname	(	AFPObj *	obj,
		char *	ibuf,
		size_t	ibuflen,
		char *	rbuf,
		size_t *	rbuflen )

afp_opendir()

int afp_opendir	(	AFPObj *	obj,
		char *	ibuf,
		size_t	ibuflen,
		char *	rbuf,
		size_t *	rbuflen )

afp_setdirparams()

int afp_setdirparams	(	AFPObj *	obj,
		char *	ibuf,
		size_t	ibuflen,
		char *	rbuf,
		size_t *	rbuflen )

afp_syncdir()

int afp_syncdir	(	AFPObj *	obj,
		char *	ibuf,
		size_t	ibuflen,
		char *	rbuf,
		size_t *	rbuflen )

check_access()

int check_access	(	const AFPObj *	obj,
		struct vol *	vol,
		char *	path,
		int	mode )

We can't use unix file's perm to support Apple's inherited protection modes. If we aren't the file's owner we can't change its perms when moving it and smb nfs,... don't even try.

cname()

struct path * cname	(	struct vol *	vol,
		struct dir *	dir,
		char **	cpath )

Resolve a catalog node name path.

1. Evaluate path type
2. Move to start dir, if we can't, it might be e.g. because of EACCES, build path from dirname, so e.g. getdirparams has sth it can chew on. curdir is dir parent then. All this is done in path_from_dir().
3. Parse next cnode name in path, cases:
4. single "\0" -> do nothing
5. two or more consecutive "\0" -> chdir("..") one or more times
6. cnode name -> copy it to path.m_name
7. Get unix name from mac name
8. Special handling of request with did 1
9. stat the cnode name
10. If it's not there, it's probably an afp_createfile|dir, return with curdir = dir parent, struct path = dirname
11. If it's there and it's a file, it must should be the last element of the requested path. Return with curdir = cnode name parent dir, struct path = filename
12. Treat symlinks like files, don't follow them
13. If it's a dir:
14. Search the dircache for it
15. If it's not in the cache, create a struct dir for it and add it to the cache
16. chdir into the dir and
17. set m_name to the mac equivalent of "."
18. goto 3

cname_mtouname()

int cname_mtouname ( const struct vol * vol, struct dir * dir, struct path * ret, int toUTF8 )

static

Convert name in client encoding to server encoding.

Convert ret->m_name to ret->u_name from client encoding to server encoding. This only gets called from cname().

Returns

0 on success, -1 on error

Note

If the passed ret->m_name is mangled, we'll demangle it

copydir()

int copydir ( struct vol * vol, struct dir * ddir, int dirfd, char * src, char * dst )

static

do a recursive copy.

deletecurdir()

int deletecurdir

(

struct vol *

vol

)

delete an empty directory

deletedir()

int deletedir ( const struct vol * vol, int dirfd, char * dir )

static

dir_add()

struct dir * dir_add	(	struct vol *	vol,
		const struct dir *	dir,
		struct path *	path,
		int	len )

Create struct dir from struct path.

Create a new struct dir from struct path. Then add it to the cache.

1. Open adouble file, get CNID from it.
2. Search the database, hinting with the CNID from (1).
3. Build fullpath and create struct dir.
4. Add it to the cache.

Parameters

[in]	vol	pointer to struct vol, possibly modified in callee
[in]	dir	pointer to parent directory
[in,out]	path	pointer to struct path with valid path->u_name
[in]	len	strlen of path->u_name

Returns

Pointer to new struct dir or NULL on error.

Note

Function also assigns path->m_name from path->u_name.

dir_free()

void dir_free

(

struct dir *

dir

)

Free a struct dir and all its members.

Parameters

dir	(rw) pointer to struct dir

dir_free_invalid_q()

void dir_free_invalid_q

(

void

)

Free the queue with invalid struct dirs.

Note

This gets called at the end of every AFP func.

dir_new()

struct dir * dir_new	(	const char *	m_name,
		const char *	u_name,
		const struct vol *	vol,
		cnid_t	pdid,
		cnid_t	did,
		bstring	path,
		struct stat *	st )

Construct struct dir.

Construct struct dir from parameters.

Parameters

[in]	m_name	directory name in UTF8-dec
[in]	u_name	directory name in server side encoding
[in]	vol	pointer to struct vol
[in]	pdid	Parent CNID
[in]	did	CNID
[in]	path	Full unix path to object
[in]	st	struct stat of object

Returns

pointer to new struct dir or NULL on error

Note

Most of the time mac name and unix name are the same.

dir_remove()

int dir_remove	(	const struct vol *	vol,
		struct dir *	dir )

Remove a file/directory from dircache with automatic curdir recovery.

This function centralizes global curdir safety for all callers. When removing a cache entry that is curdir, it attempts curdir recovery via CNID database and falls back to volume root if recovery fails.

1. Check the dir
2. Detect if removing curdir and save DID
3. Remove from cache and queue for deallocation
4. Set curdir=NULL if removing curdir (safer than dangling pointer)
5. Attempt recovery via dirlookup(saved_did)
6. If recovery fails, fallback to vol->v_root or rootParent
7. Mark entry invalid

Parameters

[in]	vol	volume pointer
[in,out]	dir	directory/file entry to remove from cache

Returns

0 on success, -1 if curdir was removed and recovery failed (curdir guaranteed non-NULL on return)

dirlookup()

struct dir * dirlookup	(	const struct vol *	vol,
		cnid_t	did )

Public CNID (Directory ID) resolution (supports files and directories).

Resolves a CNID (Directory ID) to its cached entry. This function supports both files and directories since DID can refer to either type. If cache hit, returns cache entry, if cache miss, returns CNID database record and updates cache

Parameters

[in]	vol	pointer to struct vol
[in]	did	DID to resolve

Returns

pointer to struct dir (may have DIRF_ISFILE flag for files)

dirlookup_internal()

struct dir * dirlookup_internal ( const struct vol * vol, cnid_t did, int retry, int strict )

static

Internal CNID (Directory ID) resolution with retry control.

Resolve a CNID (Directory ID), allocate a struct dir for it.

Algorithm:

1. Check for special DIDs 0 (invalid), 1 (root parent), and 2 (root).
2. Search dircache:
   • If found and valid, return cached entry
   • If strict mode, validate inode before use
3. On cache miss, query CNID database for path component
4. Recurse to build parent chain (terminates at root or cache hit)
5. Build fullpath and stat to verify existence
6. Create new struct dir and populate
7. Add new entry to cache

On ENOENT during stat (step 5), if retry=1:

• Clean stale cache entries
• Retry once via CNID (prevents TOCTOU issues)

Parameters

[in]	vol	pointer to struct vol
[in]	did	CNID to resolve
[in]	retry	1 = allow one retry on ENOENT, 0 = no retry
[in]	strict	1 = strict dircache lookup (validate with stat+inode), 0 = optimistic

Returns

pointer to struct dir, or NULL with afp_errno set

dirlookup_internal_retry()

struct dir * dirlookup_internal_retry ( const struct vol * vol, cnid_t did, int strict, bstring * fullpath_ptr, char ** upath_ptr )

static

Retry helper for dirlookup_internal on ENOENT.

When stat() fails with ENOENT, this function cleans stale cache entries and retries the lookup via CNID database. This handles race conditions where directories are renamed/moved by external processes between cache and stat.

Parameters

[in]	vol	Volume
[in]	did	Target DID that failed stat
[in]	strict	Validation mode (0=initial target, 1=parent recursion)
[in,out]	fullpath_ptr	Pointer to fullpath to cleanup
[in,out]	upath_ptr	Pointer to upath to cleanup

Returns

Retried struct dir from CNID, or NULL on failure

dirlookup_strict()

struct dir * dirlookup_strict	(	const struct vol *	vol,
		cnid_t	did )

Strict DID resolution with inode validation.

Like dirlookup(), but performs additional validation to ensure the cached directory entry matches the actual filesystem state. This prevents race conditions where a directory has been renamed/moved but the cache entry still points to the old path/has become stale.

Use this for destructive operations (delete, rename, move) where operating on the wrong object could cause data loss.

Parameters

[in]	vol	pointer to struct vol
[in]	did	DID to resolve

Returns

pointer to validated struct dir, or NULL with afp_errno set

diroffcnt()

int diroffcnt ( struct dir * dir, struct stat * st )

static

is our cached offspring count valid?

dirreenumerate()

int dirreenumerate	(	struct dir *	dir,
		struct stat *	st )

file_access()

int file_access	(	const AFPObj *	obj,
		struct vol *	vol,
		struct path *	path,
		int	mode )

get_afp_errno()

int get_afp_errno

(

const int

param

)

getdirparams()

int getdirparams	(	const AFPObj *	obj,
		const struct vol *	vol,
		uint16_t	bitmap,
		struct path *	s_path,
		struct dir *	dir,
		char *	buf,
		size_t *	buflen )

invisible_dots()

int invisible_dots ( const struct vol * vol, const char * name )

static

movecwd()

int movecwd	(	const struct vol *	vol,
		struct dir *	dir )

chdir() to dir

Parameters

[in]	vol	pointer to struct vol
[in]	dir	pointer to struct dir

Returns

0 on success, -1 on error with afp_errno set appropriately

netatalk_mkdir()

int netatalk_mkdir ( const struct vol * vol, const char * name )

static

path_error()

int path_error	(	struct path *	path,
		int	error )

path_from_dir()

struct path * path_from_dir ( struct vol * vol, struct dir * dir, struct path * ret )

static

Build struct path from struct dir.

The final movecwd in cname failed, possibly with EPERM or ENOENT. We:

1. move cwd into parent dir (we're often already there, but not always)
2. set struct path to the dirname
3. in case of AFPERR_ACCESS: the dir is there, we just can't chdir into it AFPERR_NOOBJ: the dir was there when we stated it in cname, so we have a race
   1. indicate there's no dir for this path
   2. remove the dir

renamedir()

int renamedir	(	struct vol *	vol,
		int	dirfd,
		char *	src,
		char *	dst,
		struct dir *	newparent,
		char *	newname )

Rename a directory.

Parameters

vol	volume
dirfd	-1 means ignore dirfd (or use AT_FDCWD), otherwise src is relative to dirfd
src	old unix filename (not a pathname)
dst	new unix filename (not a pathname)
newparent	curdir
newname	new mac name

set_dir_errors()

int set_dir_errors ( struct path * path, const char * where, int err )

static

setdiroffcnt()

void setdiroffcnt	(	struct dir *	dir,
		struct stat *	st,
		uint32_t	count )

setdirparams()

int setdirparams	(	struct vol *	vol,
		struct path *	path,
		uint16_t	d_bitmap,
		char *	buf )

Note

assume path == '\0' e.g. it's a directory in canonical form

Variable Documentation

afp_errno

int afp_errno

Cur_Path

struct path Cur_Path

Initial value:

= {
    0,
    "",  
    ".", 
    0,   
    NULL,
    0,   
    0,   
    {0} 
}

curdir

struct dir* curdir = &rootParent

invalid_dircache_entries

q_t* invalid_dircache_entries

rootParent

struct dir rootParent

Initial value:

= {
    NULL, NULL, NULL, NULL,          
    NULL, 0, 0, 0,                   
    0, 0, 0, 0,                      
    0, 0                             
}