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samba-mirror/source3/smbd/mangle_hash.c

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/*
Unix SMB/CIFS implementation.
Name mangling
Copyright (C) Andrew Tridgell 1992-2002
Copyright (C) Simo Sorce 2001
Copyright (C) Andrew Bartlett 2002
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 of the License, 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/* -------------------------------------------------------------------------- **
* Notable problems...
*
* March/April 1998 CRH
* - Many of the functions in this module overwrite string buffers passed to
* them. This causes a variety of problems and is, generally speaking,
* dangerous and scarry. See the kludge notes in name_map()
* below.
* - It seems that something is calling name_map() twice. The
* first call is probably some sort of test. Names which contain
* illegal characters are being doubly mangled. I'm not sure, but
* I'm guessing the problem is in server.c.
*
* -------------------------------------------------------------------------- **
*/
/* -------------------------------------------------------------------------- **
* History...
*
* March/April 1998 CRH
* Updated a bit. Rewrote is_mangled() to be a bit more selective.
* Rewrote the mangled name cache. Added comments here and there.
* &c.
* -------------------------------------------------------------------------- **
*/
#include "includes.h"
/* -------------------------------------------------------------------------- **
* External Variables...
*/
extern int case_default; /* Are conforming 8.3 names all upper or lower? */
extern BOOL case_mangle; /* If true, all chars in 8.3 should be same case. */
/* -------------------------------------------------------------------------- **
* Other stuff...
*
* magic_char - This is the magic char used for mangling. It's
* global. There is a call to lp_magicchar() in server.c
* that is used to override the initial value.
*
* MANGLE_BASE - This is the number of characters we use for name mangling.
*
* basechars - The set characters used for name mangling. This
* is static (scope is this file only).
*
* mangle() - Macro used to select a character from basechars (i.e.,
* mangle(n) will return the nth digit, modulo MANGLE_BASE).
*
* chartest - array 0..255. The index range is the set of all possible
* values of a byte. For each byte value, the content is a
* two nibble pair. See BASECHAR_MASK and ILLEGAL_MASK,
* below.
*
* ct_initialized - False until the chartest array has been initialized via
* a call to init_chartest().
*
* BASECHAR_MASK - Masks the upper nibble of a one-byte value.
*
* ILLEGAL_MASK - Masks the lower nibble of a one-byte value.
*
* isbasecahr() - Given a character, check the chartest array to see
* if that character is in the basechars set. This is
* faster than using strchr_m().
*
* isillegal() - Given a character, check the chartest array to see
* if that character is in the illegal characters set.
* This is faster than using strchr_m().
*
* mangled_cache - Cache header used for storing mangled -> original
* reverse maps.
*
* mc_initialized - False until the mangled_cache structure has been
* initialized via a call to reset_mangled_cache().
*
* MANGLED_CACHE_MAX_ENTRIES - Default maximum number of entries for the
* cache. A value of 0 indicates "infinite".
*
* MANGLED_CACHE_MAX_MEMORY - Default maximum amount of memory for the
* cache. When the cache was kept as an array of 256
* byte strings, the default cache size was 50 entries.
* This required a fixed 12.5Kbytes of memory. The
* mangled stack parameter is no longer used (though
* this might change). We're now using a fixed 16Kbyte
* maximum cache size. This will probably be much more
* than 50 entries.
*/
char magic_char = '~';
static char basechars[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ_-!@#$%";
#define MANGLE_BASE (sizeof(basechars)/sizeof(char)-1)
static unsigned char chartest[256] = { 0 };
static BOOL ct_initialized = False;
#define mangle(V) ((char)(basechars[(V) % MANGLE_BASE]))
#define BASECHAR_MASK 0xf0
#define ILLEGAL_MASK 0x0f
#define isbasechar(C) ( (chartest[ ((C) & 0xff) ]) & BASECHAR_MASK )
#define isillegal(C) ( (chartest[ ((C) & 0xff) ]) & ILLEGAL_MASK )
static ubi_cacheRoot mangled_cache[1] = { { { 0, 0, 0, 0 }, 0, 0, 0, 0, 0, 0 } };
static BOOL mc_initialized = False;
#define MANGLED_CACHE_MAX_ENTRIES 1024
#define MANGLED_CACHE_MAX_MEMORY 0
/* -------------------------------------------------------------------------- **
* External Variables...
*/
extern int case_default; /* Are conforming 8.3 names all upper or lower? */
extern BOOL case_mangle; /* If true, all chars in 8.3 should be same case. */
/* -------------------------------------------------------------------- */
static NTSTATUS has_valid_chars(const smb_ucs2_t *s, BOOL allow_wildcards)
{
if (!s || !*s)
return NT_STATUS_INVALID_PARAMETER;
/* CHECK: this should not be necessary if the ms wild chars
are not valid in valid.dat --- simo */
if (!allow_wildcards && ms_has_wild_w(s))
return NT_STATUS_UNSUCCESSFUL;
while (*s) {
if(!isvalid83_w(*s))
return NT_STATUS_UNSUCCESSFUL;
s++;
}
return NT_STATUS_OK;
}
/* return False if something fail and
* return 2 alloced unicode strings that contain prefix and extension
*/
static NTSTATUS mangle_get_prefix(const smb_ucs2_t *ucs2_string, smb_ucs2_t **prefix,
smb_ucs2_t **extension, BOOL allow_wildcards)
{
size_t ext_len;
smb_ucs2_t *p;
*extension = 0;
*prefix = strdup_w(ucs2_string);
if (!*prefix) {
return NT_STATUS_NO_MEMORY;
}
if ((p = strrchr_w(*prefix, UCS2_CHAR('.')))) {
ext_len = strlen_w(p+1);
if ((ext_len > 0) && (ext_len < 4) && (p != *prefix) &&
(NT_STATUS_IS_OK(has_valid_chars(p+1,allow_wildcards)))) /* check extension */ {
*p = 0;
*extension = strdup_w(p+1);
if (!*extension) {
SAFE_FREE(*prefix);
return NT_STATUS_NO_MEMORY;
}
}
}
return NT_STATUS_OK;
}
/* ************************************************************************** **
* Return NT_STATUS_UNSUCCESSFUL if a name is a special msdos reserved name.
*
* Input: fname - String containing the name to be tested.
*
* Output: NT_STATUS_UNSUCCESSFUL, if the name matches one of the list of reserved names.
*
* Notes: This is a static function called by is_8_3(), below.
*
* ************************************************************************** **
*/
static NTSTATUS is_valid_name(const smb_ucs2_t *fname, BOOL allow_wildcards)
{
smb_ucs2_t *str, *p;
NTSTATUS ret = NT_STATUS_OK;
if (!fname || !*fname)
return NT_STATUS_INVALID_PARAMETER;
/* . and .. are valid names. */
if (strcmp_wa(fname, ".")==0 || strcmp_wa(fname, "..")==0)
return NT_STATUS_OK;
/* Name cannot start with '.' */
if (*fname == UCS2_CHAR('.'))
return NT_STATUS_UNSUCCESSFUL;
ret = has_valid_chars(fname, allow_wildcards);
if (!NT_STATUS_IS_OK(ret))
return ret;
str = strdup_w(fname);
p = strchr_w(str, UCS2_CHAR('.'));
if (p && p[1] == UCS2_CHAR(0)) {
/* Name cannot end in '.' */
SAFE_FREE(str);
return NT_STATUS_UNSUCCESSFUL;
}
if (p)
*p = 0;
strupper_w(str);
p = &(str[1]);
switch(str[0])
{
case UCS2_CHAR('A'):
if(strcmp_wa(p, "UX") == 0)
ret = NT_STATUS_UNSUCCESSFUL;
break;
case UCS2_CHAR('C'):
if((strcmp_wa(p, "LOCK$") == 0)
|| (strcmp_wa(p, "ON") == 0)
|| (strcmp_wa(p, "OM1") == 0)
|| (strcmp_wa(p, "OM2") == 0)
|| (strcmp_wa(p, "OM3") == 0)
|| (strcmp_wa(p, "OM4") == 0)
)
ret = NT_STATUS_UNSUCCESSFUL;
break;
case UCS2_CHAR('L'):
if((strcmp_wa(p, "PT1") == 0)
|| (strcmp_wa(p, "PT2") == 0)
|| (strcmp_wa(p, "PT3") == 0)
)
ret = NT_STATUS_UNSUCCESSFUL;
break;
case UCS2_CHAR('N'):
if(strcmp_wa(p, "UL") == 0)
ret = NT_STATUS_UNSUCCESSFUL;
break;
case UCS2_CHAR('P'):
if(strcmp_wa(p, "RN") == 0)
ret = NT_STATUS_UNSUCCESSFUL;
break;
default:
break;
}
SAFE_FREE(str);
return ret;
}
static NTSTATUS is_8_3_w(const smb_ucs2_t *fname, BOOL allow_wildcards)
{
smb_ucs2_t *pref = 0, *ext = 0;
size_t plen;
NTSTATUS ret = NT_STATUS_UNSUCCESSFUL;
if (!fname || !*fname)
return NT_STATUS_INVALID_PARAMETER;
if (strlen_w(fname) > 12)
return NT_STATUS_UNSUCCESSFUL;
if (strcmp_wa(fname, ".") == 0 || strcmp_wa(fname, "..") == 0)
return NT_STATUS_OK;
if (!NT_STATUS_IS_OK(is_valid_name(fname, allow_wildcards)))
goto done;
if (!NT_STATUS_IS_OK(mangle_get_prefix(fname, &pref, &ext, allow_wildcards)))
goto done;
plen = strlen_w(pref);
if (strchr_wa(pref, '.'))
goto done;
if (plen < 1 || plen > 8)
goto done;
if (ext && (strlen_w(ext) > 3))
goto done;
ret = NT_STATUS_OK;
done:
SAFE_FREE(pref);
SAFE_FREE(ext);
return ret;
}
static BOOL is_8_3(const char *fname, BOOL check_case, BOOL allow_wildcards)
{
const char *f;
smb_ucs2_t *ucs2name;
NTSTATUS ret = NT_STATUS_UNSUCCESSFUL;
if (!fname || !*fname)
return False;
if ((f = strrchr(fname, '/')) == NULL)
f = fname;
else
f++;
if (strlen(f) > 12)
return False;
ucs2name = acnv_uxu2(f);
if (!ucs2name) {
DEBUG(0,("is_8_3: internal error acnv_uxu2() failed!\n"));
goto done;
}
ret = is_8_3_w(ucs2name, allow_wildcards);
done:
SAFE_FREE(ucs2name);
if (!NT_STATUS_IS_OK(ret)) {
return False;
}
return True;
}
/* -------------------------------------------------------------------------- **
* Functions...
*/
/* ************************************************************************** **
* Initialize the static character test array.
*
* Input: none
*
* Output: none
*
* Notes: This function changes (loads) the contents of the <chartest>
* array. The scope of <chartest> is this file.
*
* ************************************************************************** **
*/
static void init_chartest( void )
{
const char *illegalchars = "*\\/?<>|\":";
const unsigned char *s;
memset( (char *)chartest, '\0', 256 );
for( s = (const unsigned char *)illegalchars; *s; s++ )
chartest[*s] = ILLEGAL_MASK;
for( s = (const unsigned char *)basechars; *s; s++ )
chartest[*s] |= BASECHAR_MASK;
ct_initialized = True;
}
/* ************************************************************************** **
* Return True if the name *could be* a mangled name.
*
* Input: s - A path name - in UNIX pathname format.
*
* Output: True if the name matches the pattern described below in the
* notes, else False.
*
* Notes: The input name is *not* tested for 8.3 compliance. This must be
* done separately. This function returns true if the name contains
* a magic character followed by excactly two characters from the
* basechars list (above), which in turn are followed either by the
* nul (end of string) byte or a dot (extension) or by a '/' (end of
* a directory name).
*
* ************************************************************************** **
*/
static BOOL is_mangled(const char *s)
{
char *magic;
if( !ct_initialized )
init_chartest();
magic = strchr_m( s, magic_char );
while( magic && magic[1] && magic[2] ) { /* 3 chars, 1st is magic. */
if( ('.' == magic[3] || '/' == magic[3] || !(magic[3])) /* Ends with '.' or nul or '/' ? */
&& isbasechar( toupper(magic[1]) ) /* is 2nd char basechar? */
&& isbasechar( toupper(magic[2]) ) ) /* is 3rd char basechar? */
return( True ); /* If all above, then true, */
magic = strchr_m( magic+1, magic_char ); /* else seek next magic. */
}
return( False );
}
/* ************************************************************************** **
* Compare two cache keys and return a value indicating their ordinal
* relationship.
*
* Input: ItemPtr - Pointer to a comparison key. In this case, this will
* be a mangled name string.
* NodePtr - Pointer to a node in the cache. The node structure
* will be followed in memory by a mangled name string.
*
* Output: A signed integer, as follows:
* (x < 0) <==> Key1 less than Key2
* (x == 0) <==> Key1 equals Key2
* (x > 0) <==> Key1 greater than Key2
*
* Notes: This is a ubiqx-style comparison routine. See ubi_BinTree for
* more info.
*
* ************************************************************************** **
*/
static signed int cache_compare( ubi_btItemPtr ItemPtr, ubi_btNodePtr NodePtr )
{
char *Key1 = (char *)ItemPtr;
char *Key2 = (char *)(((ubi_cacheEntryPtr)NodePtr) + 1);
return( StrCaseCmp( Key1, Key2 ) );
}
/* ************************************************************************** **
* Free a cache entry.
*
* Input: WarrenZevon - Pointer to the entry that is to be returned to
* Nirvana.
* Output: none.
*
* Notes: This function gets around the possibility that the standard
* free() function may be implemented as a macro, or other evil
* subversions (oh, so much fun).
*
* ************************************************************************** **
*/
static void cache_free_entry( ubi_trNodePtr WarrenZevon )
{
ZERO_STRUCTP(WarrenZevon);
SAFE_FREE( WarrenZevon );
}
/* ************************************************************************** **
* Initializes or clears the mangled cache.
*
* Input: none.
* Output: none.
*
* Notes: There is a section below that is commented out. It shows how
* one might use lp_ calls to set the maximum memory and entry size
* of the cache. You might also want to remove the constants used
* in ubi_cacheInit() and replace them with lp_ calls. If so, then
* the calls to ubi_cacheSetMax*() would be moved into the else
* clause. Another option would be to pass in the max_entries and
* max_memory values as parameters. crh 09-Apr-1998.
*
* ************************************************************************** **
*/
static void mangle_reset( void )
{
if( !mc_initialized ) {
(void)ubi_cacheInit( mangled_cache,
cache_compare,
cache_free_entry,
MANGLED_CACHE_MAX_ENTRIES,
MANGLED_CACHE_MAX_MEMORY );
mc_initialized = True;
} else {
(void)ubi_cacheClear( mangled_cache );
}
/*
(void)ubi_cacheSetMaxEntries( mangled_cache, lp_mangled_cache_entries() );
(void)ubi_cacheSetMaxMemory( mangled_cache, lp_mangled_cache_memory() );
*/
}
/* ************************************************************************** **
* Add a mangled name into the cache.
*
* Notes: If the mangled cache has not been initialized, then the
* function will simply fail. It could initialize the cache,
* but that's not the way it was done before I changed the
* cache mechanism, so I'm sticking with the old method.
*
* If the extension of the raw name maps directly to the
* extension of the mangled name, then we'll store both names
* *without* extensions. That way, we can provide consistent
* reverse mangling for all names that match. The test here is
* a bit more careful than the one done in earlier versions of
* mangle.c:
*
* - the extension must exist on the raw name,
* - it must be all lower case
* - it must match the mangled extension (to prove that no
* mangling occurred).
*
* crh 07-Apr-1998
*
* ************************************************************************** **
*/
static void cache_mangled_name( char *mangled_name, char *raw_name )
{
ubi_cacheEntryPtr new_entry;
char *s1;
char *s2;
size_t mangled_len;
size_t raw_len;
size_t i;
/* If the cache isn't initialized, give up. */
if( !mc_initialized )
return;
/* Init the string lengths. */
mangled_len = strlen( mangled_name );
raw_len = strlen( raw_name );
/* See if the extensions are unmangled. If so, store the entry
* without the extension, thus creating a "group" reverse map.
*/
s1 = strrchr( mangled_name, '.' );
if( s1 && (s2 = strrchr( raw_name, '.' )) ) {
i = 1;
while( s1[i] && (tolower( s1[i] ) == s2[i]) )
i++;
if( !s1[i] && !s2[i] ) {
mangled_len -= i;
raw_len -= i;
}
}
/* Allocate a new cache entry. If the allocation fails, just return. */
i = sizeof( ubi_cacheEntry ) + mangled_len + raw_len + 2;
new_entry = malloc( i );
if( !new_entry )
return;
/* Fill the new cache entry, and add it to the cache. */
s1 = (char *)(new_entry + 1);
s2 = (char *)&(s1[mangled_len + 1]);
safe_strcpy( s1, mangled_name, mangled_len );
safe_strcpy( s2, raw_name, raw_len );
ubi_cachePut( mangled_cache, i, new_entry, s1 );
}
/* ************************************************************************** **
* Check for a name on the mangled name stack
*
* Input: s - Input *and* output string buffer.
*
* Output: True if the name was found in the cache, else False.
*
* Notes: If a reverse map is found, the function will overwrite the string
* space indicated by the input pointer <s>. This is frightening.
* It should be rewritten to return NULL if the long name was not
* found, and a pointer to the long name if it was found.
*
* ************************************************************************** **
*/
static BOOL check_cache( char *s )
{
ubi_cacheEntryPtr FoundPtr;
char *ext_start = NULL;
char *found_name;
char *saved_ext = NULL;
/* If the cache isn't initialized, give up. */
if( !mc_initialized )
return( False );
FoundPtr = ubi_cacheGet( mangled_cache, (ubi_trItemPtr)s );
/* If we didn't find the name *with* the extension, try without. */
if( !FoundPtr ) {
ext_start = strrchr( s, '.' );
if( ext_start ) {
if((saved_ext = strdup(ext_start)) == NULL)
return False;
*ext_start = '\0';
FoundPtr = ubi_cacheGet( mangled_cache, (ubi_trItemPtr)s );
/*
* At this point s is the name without the
* extension. We re-add the extension if saved_ext
* is not null, before freeing saved_ext.
*/
}
}
/* Okay, if we haven't found it we're done. */
if( !FoundPtr ) {
if(saved_ext) {
/* Replace the saved_ext as it was truncated. */
(void)pstrcat( s, saved_ext );
SAFE_FREE(saved_ext);
}
return( False );
}
/* If we *did* find it, we need to copy it into the string buffer. */
found_name = (char *)(FoundPtr + 1);
found_name += (strlen( found_name ) + 1);
(void)pstrcpy( s, found_name );
if( saved_ext ) {
/* Replace the saved_ext as it was truncated. */
(void)pstrcat( s, saved_ext );
SAFE_FREE(saved_ext);
}
return( True );
}
/*****************************************************************************
* do the actual mangling to 8.3 format
* the buffer must be able to hold 13 characters (including the null)
*****************************************************************************
*/
static void to_8_3(char *s)
{
int csum;
char *p;
char extension[4];
char base[9];
int baselen = 0;
int extlen = 0;
extension[0] = 0;
base[0] = 0;
p = strrchr(s,'.');
if( p && (strlen(p+1) < (size_t)4) ) {
BOOL all_normal = ( strisnormal(p+1) ); /* XXXXXXXXX */
if( all_normal && p[1] != 0 ) {
*p = 0;
csum = str_checksum( s );
*p = '.';
} else
csum = str_checksum(s);
} else
csum = str_checksum(s);
strupper_m( s );
if( p ) {
if( p == s )
safe_strcpy( extension, "___", 3 );
else {
*p++ = 0;
while( *p && extlen < 3 ) {
if ( *p != '.') {
extension[extlen++] = p[0];
}
p++;
}
extension[extlen] = 0;
}
}
p = s;
while( *p && baselen < 5 ) {
if (*p != '.') {
base[baselen++] = p[0];
}
p++;
}
base[baselen] = 0;
csum = csum % (MANGLE_BASE*MANGLE_BASE);
(void)slprintf(s, 12, "%s%c%c%c",
base, magic_char, mangle( csum/MANGLE_BASE ), mangle( csum ) );
if( *extension ) {
(void)pstrcat( s, "." );
(void)pstrcat( s, extension );
}
}
/*****************************************************************************
* Convert a filename to DOS format. Return True if successful.
*
* Input: OutName - Source *and* destination buffer.
*
* NOTE that OutName must point to a memory space that
* is at least 13 bytes in size!
*
* need83 - If False, name mangling will be skipped unless the
* name contains illegal characters. Mapping will still
* be done, if appropriate. This is probably used to
* signal that a client does not require name mangling,
* thus skipping the name mangling even on shares which
* have name-mangling turned on.
* cache83 - If False, the mangled name cache will not be updated.
* This is usually used to prevent that we overwrite
* a conflicting cache entry prematurely, i.e. before
* we know whether the client is really interested in the
* current name. (See PR#13758). UKD.
*
* Output: Returns False only if the name wanted mangling but the share does
* not have name mangling turned on.
*
* ****************************************************************************
*/
static void name_map(char *OutName, BOOL need83, BOOL cache83)
{
smb_ucs2_t *OutName_ucs2;
DEBUG(5,("name_map( %s, need83 = %s, cache83 = %s)\n", OutName,
need83 ? "True" : "False", cache83 ? "True" : "False"));
if (push_ucs2_allocate(&OutName_ucs2, OutName) == (size_t)-1) {
DEBUG(0, ("push_ucs2_allocate failed!\n"));
return;
}
if( !need83 && !NT_STATUS_IS_OK(is_valid_name(OutName_ucs2, False)))
need83 = True;
/* check if it's already in 8.3 format */
if (need83 && !NT_STATUS_IS_OK(is_8_3_w(OutName_ucs2, False))) {
char *tmp = NULL;
/* mangle it into 8.3 */
if (cache83)
tmp = strdup(OutName);
to_8_3(OutName);
if(tmp != NULL) {
cache_mangled_name(OutName, tmp);
SAFE_FREE(tmp);
}
}
DEBUG(5,("name_map() ==> [%s]\n", OutName));
SAFE_FREE(OutName_ucs2);
}
/*
the following provides the abstraction layer to make it easier
to drop in an alternative mangling implementation
*/
static struct mangle_fns mangle_fns = {
is_mangled,
is_8_3,
mangle_reset,
check_cache,
name_map
};
/* return the methods for this mangling implementation */
struct mangle_fns *mangle_hash_init(void)
{
mangle_reset();
return &mangle_fns;
}