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samba-mirror/source3/smbd/mangle_hash.c
Andrew Bartlett 455bb6de90 Some small fixes to our charset conversion code:
- Treat the NMB names in the 'session request' packet as 'ASCII'.  This means
   that we do not get invalid multibyte from the wire, even if we truncate
   in the conversion.  (Otherwise we panic when we try to strupper_m it).

 - Remove acnv_uxu2(), as it was duplicated by push_ucs2_allocate()
 - Remove acnv_dosu2(), as it is not used.

 - In push_ucs2(), with the STR_UPPER flag, do the case conversion *after*
   the UCS2 conversion, when it we know that the length can't change.  Also
   faster, as we don't need to do another 2 UCS2 conversions.

Andrew Bartlett
(This used to be commit 912035af1178424583d0bf887a391a0cac2acd87)
2003-07-27 02:28:25 +00:00

782 lines
23 KiB
C

/*
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;
size_t size;
if (!fname || !*fname)
return False;
if ((f = strrchr(fname, '/')) == NULL)
f = fname;
else
f++;
if (strlen(f) > 12)
return False;
size = push_ucs2_allocate(&ucs2name, f);
if (size == (size_t)-1) {
DEBUG(0,("is_8_3: internal error push_ucs2_allocate() 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;
}