/* Unix SMB/CIFS implementation. Name mangling Copyright (C) Andrew Tridgell 1992-2002 Copyright (C) Simo Sorce 2001 Copyright (C) Andrew Bartlett 2002 Copyright (C) Jeremy Allison 2007 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 3 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, see <http://www.gnu.org/licenses/>. */ #include "includes.h" #include "smbd/globals.h" #include "mangle.h" /* -------------------------------------------------------------------------- ** * 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 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. * * 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(). * */ static const char basechars[43]="0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ_-!@#$%"; #define MANGLE_BASE (sizeof(basechars)/sizeof(char)-1) #define mangle(V) ((char)(basechars[(V) % MANGLE_BASE])) #define BASECHAR_MASK 0xf0 #define isbasechar(C) ( (chartest[ ((C) & 0xff) ]) & BASECHAR_MASK ) /* -------------------------------------------------------------------- */ static NTSTATUS has_valid_83_chars(const smb_ucs2_t *s, bool allow_wildcards) { if (!*s) { return NT_STATUS_INVALID_PARAMETER; } 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; } static NTSTATUS has_illegal_chars(const smb_ucs2_t *s, bool allow_wildcards) { if (!allow_wildcards && ms_has_wild_w(s)) { return NT_STATUS_UNSUCCESSFUL; } while (*s) { if (*s <= 0x1f) { /* Control characters. */ return NT_STATUS_UNSUCCESSFUL; } switch(*s) { case UCS2_CHAR('\\'): case UCS2_CHAR('/'): case UCS2_CHAR('|'): case UCS2_CHAR(':'): 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_83_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. * or contains illegal characters. * * Input: fname - String containing the name to be tested. * * Output: NT_STATUS_UNSUCCESSFUL, if the condition above is true. * * 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, bool only_8_3) { smb_ucs2_t *str, *p; size_t num_ucs2_chars; 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; if (only_8_3) { ret = has_valid_83_chars(fname, allow_wildcards); if (!NT_STATUS_IS_OK(ret)) return ret; } ret = has_illegal_chars(fname, allow_wildcards); if (!NT_STATUS_IS_OK(ret)) return ret; /* Name can't end in '.' or ' ' */ num_ucs2_chars = strlen_w(fname); if (fname[num_ucs2_chars-1] == UCS2_CHAR('.') || fname[num_ucs2_chars-1] == UCS2_CHAR(' ')) { return NT_STATUS_UNSUCCESSFUL; } str = strdup_w(fname); /* Truncate copy after the first dot. */ p = strchr_w(str, UCS2_CHAR('.')); 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; /* Name cannot start with '.' */ if (*fname == UCS2_CHAR('.')) return NT_STATUS_UNSUCCESSFUL; if (!NT_STATUS_IS_OK(is_valid_name(fname, allow_wildcards, True))) 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 struct share_params *p) { const char *f; smb_ucs2_t *ucs2name; NTSTATUS ret = NT_STATUS_UNSUCCESSFUL; size_t size; char magic_char; magic_char = lp_magicchar(p); if (!fname || !*fname) return False; if ((f = strrchr(fname, '/')) == NULL) f = fname; else f++; if (strlen(f) > 12) return False; if (!push_ucs2_talloc(NULL, &ucs2name, f, &size)) { DEBUG(0,("is_8_3: internal error push_ucs2_talloc() failed!\n")); goto done; } ret = is_8_3_w(ucs2name, allow_wildcards); done: TALLOC_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 unsigned char *s; chartest = SMB_MALLOC_ARRAY(unsigned char, 256); SMB_ASSERT(chartest != NULL); memset(chartest, '\0', 256); for( s = (const unsigned char *)basechars; *s; s++ ) { chartest[*s] |= BASECHAR_MASK; } } /* ************************************************************************** ** * 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, const struct share_params *p) { char *magic; char magic_char; magic_char = lp_magicchar(p); if (chartest == NULL) { 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_ascii(magic[1]) ) /* is 2nd char basechar? */ && isbasechar( toupper_ascii(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 ); } /*************************************************************************** Initializes or clears the mangled cache. ***************************************************************************/ static void mangle_reset( void ) { /* We could close and re-open the tdb here... should we ? The old code did the equivalent... JRA. */ } /*************************************************************************** Add a mangled name into the cache. 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( const char mangled_name[13], const char *raw_name ) { TDB_DATA data_val; char mangled_name_key[13]; char *s1 = NULL; char *s2 = NULL; /* If the cache isn't initialized, give up. */ if( !tdb_mangled_cache ) return; /* Init the string lengths. */ safe_strcpy(mangled_name_key, mangled_name, sizeof(mangled_name_key)-1); /* See if the extensions are unmangled. If so, store the entry * without the extension, thus creating a "group" reverse map. */ s1 = strrchr( mangled_name_key, '.' ); if( s1 && (s2 = strrchr( raw_name, '.' )) ) { size_t i = 1; while( s1[i] && (tolower_ascii( s1[i] ) == s2[i]) ) i++; if( !s1[i] && !s2[i] ) { /* Truncate at the '.' */ *s1 = '\0'; /* * DANGER WILL ROBINSON - this * is changing a const string via * an aliased pointer ! Remember to * put it back once we've used it. * JRA */ *s2 = '\0'; } } /* Allocate a new cache entry. If the allocation fails, just return. */ data_val = string_term_tdb_data(raw_name); if (tdb_store_bystring(tdb_mangled_cache, mangled_name_key, data_val, TDB_REPLACE) != 0) { DEBUG(0,("cache_mangled_name: Error storing entry %s -> %s\n", mangled_name_key, raw_name)); } else { DEBUG(5,("cache_mangled_name: Stored entry %s -> %s\n", mangled_name_key, raw_name)); } /* Restore the change we made to the const string. */ if (s2) { *s2 = '.'; } } /* ************************************************************************** ** * Check for a name on the mangled name stack * * Input: s - Input *and* output string buffer. * maxlen - space in i/o 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 lookup_name_from_8_3(TALLOC_CTX *ctx, const char *in, char **out, /* talloced on the given context. */ const struct share_params *p) { TDB_DATA data_val; char *saved_ext = NULL; char *s = talloc_strdup(ctx, in); char magic_char; magic_char = lp_magicchar(p); /* If the cache isn't initialized, give up. */ if(!s || !tdb_mangled_cache ) { TALLOC_FREE(s); return False; } data_val = tdb_fetch_bystring(tdb_mangled_cache, s); /* If we didn't find the name *with* the extension, try without. */ if(data_val.dptr == NULL || data_val.dsize == 0) { char *ext_start = strrchr( s, '.' ); if( ext_start ) { if((saved_ext = talloc_strdup(ctx,ext_start)) == NULL) { TALLOC_FREE(s); return False; } *ext_start = '\0'; data_val = tdb_fetch_bystring(tdb_mangled_cache, 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(data_val.dptr == NULL || data_val.dsize == 0) { TALLOC_FREE(saved_ext); TALLOC_FREE(s); return False; } /* If we *did* find it, we need to talloc it on the given ctx. */ if (saved_ext) { *out = talloc_asprintf(ctx, "%s%s", (char *)data_val.dptr, saved_ext); } else { *out = talloc_strdup(ctx, (char *)data_val.dptr); } TALLOC_FREE(s); TALLOC_FREE(saved_ext); SAFE_FREE(data_val.dptr); return *out ? True : False; } /***************************************************************************** Do the actual mangling to 8.3 format. *****************************************************************************/ static bool to_8_3(char magic_char, const char *in, char out[13], int default_case) { int csum; char *p; char extension[4]; char base[9]; int baselen = 0; int extlen = 0; char *s = SMB_STRDUP(in); extension[0] = 0; base[0] = 0; if (!s) { return False; } p = strrchr(s,'.'); if( p && (strlen(p+1) < (size_t)4) ) { bool all_normal = ( strisnormal(p+1, default_case) ); /* 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 (isbasechar(*p)) { base[baselen++] = p[0]; } p++; } base[baselen] = 0; csum = csum % (MANGLE_BASE*MANGLE_BASE); memcpy(out, base, baselen); out[baselen] = magic_char; out[baselen+1] = mangle( csum/MANGLE_BASE ); out[baselen+2] = mangle( csum ); if( *extension ) { out[baselen+3] = '.'; safe_strcpy(&out[baselen+4], extension, 3); } SAFE_FREE(s); return True; } static bool must_mangle(const char *name, const struct share_params *p) { smb_ucs2_t *name_ucs2 = NULL; NTSTATUS status; size_t converted_size; char magic_char; magic_char = lp_magicchar(p); if (!push_ucs2_talloc(NULL, &name_ucs2, name, &converted_size)) { DEBUG(0, ("push_ucs2_talloc failed!\n")); return False; } status = is_valid_name(name_ucs2, False, False); TALLOC_FREE(name_ucs2); /* We return true if we *must* mangle, so if it's * a valid name (status == OK) then we must return * false. Bug #6939. */ return !NT_STATUS_IS_OK(status); } /***************************************************************************** * Convert a filename to DOS format. Return True if successful. * Input: in Incoming name. * * out 8.3 DOS name. * * 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. * * **************************************************************************** */ static bool hash_name_to_8_3(const char *in, char out[13], bool cache83, int default_case, const struct share_params *p) { smb_ucs2_t *in_ucs2 = NULL; size_t converted_size; char magic_char; magic_char = lp_magicchar(p); DEBUG(5,("hash_name_to_8_3( %s, cache83 = %s)\n", in, cache83 ? "True" : "False")); if (!push_ucs2_talloc(NULL, &in_ucs2, in, &converted_size)) { DEBUG(0, ("push_ucs2_talloc failed!\n")); return False; } /* If it's already 8.3, just copy. */ if (NT_STATUS_IS_OK(is_valid_name(in_ucs2, False, False)) && NT_STATUS_IS_OK(is_8_3_w(in_ucs2, False))) { TALLOC_FREE(in_ucs2); safe_strcpy(out, in, 12); return True; } TALLOC_FREE(in_ucs2); if (!to_8_3(magic_char, in, out, default_case)) { return False; } cache_mangled_name(out, in); DEBUG(5,("hash_name_to_8_3(%s) ==> [%s]\n", in, out)); return True; } /* the following provides the abstraction layer to make it easier to drop in an alternative mangling implementation */ static const struct mangle_fns mangle_hash_fns = { mangle_reset, is_mangled, must_mangle, is_8_3, lookup_name_from_8_3, hash_name_to_8_3 }; /* return the methods for this mangling implementation */ const struct mangle_fns *mangle_hash_init(void) { mangle_reset(); /* Create the in-memory tdb using our custom hash function. */ tdb_mangled_cache = tdb_open_ex("mangled_cache", 1031, TDB_INTERNAL, (O_RDWR|O_CREAT), 0644, NULL, fast_string_hash); return &mangle_hash_fns; }