--- parser3/src/main/untaint.C 2003/09/23 10:37:05 1.118.2.2 +++ parser3/src/main/untaint.C 2009/01/12 07:17:20 1.143 @@ -1,11 +1,11 @@ /** @file Parser: String class part: untaint mechanizm. - Copyright(c) 2001-2003 ArtLebedev Group (http://www.artlebedev.com) + Copyright(c) 2001-2005 ArtLebedev Group (http://www.artlebedev.com) Author: Alexandr Petrosian (http://paf.design.ru) */ -static const char* IDENT_UNTAINT_C="$Date: 2003/09/23 10:37:05 $"; +static const char * const IDENT_UNTAINT_C="$Date: 2009/01/12 07:17:20 $"; #include "pa_string.h" @@ -23,15 +23,10 @@ extern "C" { // author forgot to do that #include "ec.h" } -#define PA_SQL - -#ifdef PA_SQL #include "pa_sql_connection.h" -#endif // defines - #undef CORD_ec_append // redefining to intercept flushes and implement whitespace optimization // of all consequent white space chars leaving only first one @@ -39,7 +34,7 @@ extern "C" { // author forgot to do that { \ bool skip=false; \ if(optimize) switch(c) { \ - case ' ': case '\r': case '\n': case '\t': \ + case ' ': case '\n': case '\t': \ if(whitespace) \ skip=true; /*skipping subsequent*/ \ else \ @@ -58,12 +53,12 @@ extern "C" { // author forgot to do that } -#define escape(action) \ +#define escape_fragment(action) \ for(; fragment_length--; CORD_next(info->pos)) { \ char c=CORD_pos_fetch(info->pos); \ action \ } -#define _default default: CORD_ec_append(info->result, c); break +#define _default CORD_ec_append(info->result, c) #define encode(need_encode_func, prefix, otherwise) \ if(need_encode_func(c)) { \ static const char* hex="0123456789ABCDEF"; \ @@ -72,61 +67,41 @@ extern "C" { // author forgot to do that CORD_ec_append(info->result, hex[((unsigned char)c)%0x10]); \ } else \ CORD_ec_append(info->result, otherwise); -#define to_char(c) CORD_ec_append(info->result, c) -#define to_string(s) CORD_ec_append_cord(info->result, s) +#define to_char(c) { CORD_ec_append(info->result, c); whitespace=false; } +#define to_string(s) { CORD_ec_append_cord(info->result, s); whitespace=false; } inline bool need_file_encode(unsigned char c){ // russian letters and space ENABLED // encoding only these... return strchr( - "*?'\"<>|" + "*?'\"<>|" #ifndef WIN32 - ":\\" + ":\\" #endif - , c)!=0; + , c)!=0; } + inline bool need_uri_encode(unsigned char c){ - if((c>='0') &&(c<='9') ||(c>='A') &&(c<='Z') ||(c>='a') &&(c<='z')) + if((c>='0') &&(c<='9') ||(c>='A') &&(c<='Z') ||(c>='a') &&(c<='z')) return false; - return !strchr("_-./", c); + return !strchr("_-./", c); } + inline bool need_http_header_encode(unsigned char c){ - if(strchr(" , :", c)) + if(strchr(" , :", c)) return false; return need_uri_encode(c); } -// - -static const char* String_Untaint_lang_name[]={ - "U", ///< zero value handy for hash lookup @see untaint_lang_name2enum - "C", ///< clean - "T", ///< tainted, untaint language as assigned later - // untaint languages. assigned by ^untaint[lang]{...} - "P", - /**< - leave language built into string being appended. - just a flag, that value not stored - */ - "A", ///< leave all characters intact - "F", ///< file specification - "H", ///< ext in HTTP response header - "M", ///< text in mail header - "URI", ///< text in uri - "T", ///< ^table:set body - "SQL", ///< ^table:sql body - "JS", ///< JavaScript code - "XML", ///< ^dom:set xml - "HTML" ///< HTML code (for editing) -}; - +inline bool need_regex_escape(unsigned char c){ + return strchr("\\^$.[]|()?*+{}-", c)!=0; +} // String /* - HTTP-header = field-name ":" [ field-value ] CRLF field-name = token @@ -170,34 +145,36 @@ inline bool need_quote_http_header(const #ifndef DOXYGEN struct Append_fragment_info { String::Language lang; - const StringBody dest_body; String::Languages* dest_languages; + size_t dest_body_plan_length; }; #endif int append_fragment_optimizing(char alang, size_t asize, Append_fragment_info* info) { - const String::Language lang=(String::Language)alang; + const String::Language lang=(String::Language)(unsigned char)alang; // main idea here: // tainted piece would get OPTIMIZED bit from 'lang' // clean piece would be marked OPTIMIZED manually // pieces with determined languages [not tainted|clean] would retain theirs langs - info->dest_languages->append(info->dest_body, - lang==String::Language::L_TAINTED? + info->dest_languages->append(info->dest_body_plan_length, + lang==String::L_TAINTED? info->lang - :lang==String::Language::L_CLEAN? - (String::Language)(String::Language::L_CLEAN|String::Language::L_OPTIMIZE_BIT) // ORing with OPTIMIZED flag + :lang==String::L_CLEAN? + (String::Language)(String::L_CLEAN|String::L_OPTIMIZE_BIT) // ORing with OPTIMIZED flag :lang, asize); + info->dest_body_plan_length+=asize; return 0; // 0=continue } int append_fragment_nonoptimizing(char alang, size_t asize, Append_fragment_info* info) { - const String::Language lang=(String::Language)alang; + const String::Language lang=(String::Language)(unsigned char)alang; // The core idea: tainted pieces got marked with context's lang - info->dest_languages->append(info->dest_body, - lang==String::Language::L_TAINTED? + info->dest_languages->append(info->dest_body_plan_length, + lang==String::L_TAINTED? info->lang :lang, asize); + info->dest_body_plan_length+=asize; return 0; // 0=continue } @@ -215,11 +192,11 @@ String& String::append_to(String& dest, // first: fragment infos if(lang==L_PASS_APPENDED) // without language-change? - dest.langs.append(dest.body, body, langs); + dest.langs.append(dest.body, body.length(), langs); else if(forced) //forcing passed lang? dest.langs.append(dest.body, lang, length()); else { - Append_fragment_info info={lang, dest.body, &dest.langs}; + Append_fragment_info info={lang, &dest.langs, dest.body.length()}; langs.for_each(body, lang&L_OPTIMIZE_BIT? append_fragment_optimizing :append_fragment_nonoptimizing, &info); @@ -228,6 +205,7 @@ String& String::append_to(String& dest, // next: letters dest.body<=n @@ -310,7 +289,7 @@ struct Cstr_to_string_body_block_info { String::Language lang; SQL_Connection* connection; const Request_charsets* charsets; - const StringBody* body; + const String::Body* body; // output CORD_ec result; @@ -319,24 +298,24 @@ struct Cstr_to_string_body_block_info { CORD_pos pos; size_t fragment_begin; bool whitespace; + const char* exception; }; #endif int cstr_to_string_body_block(char alang, size_t fragment_length, Cstr_to_string_body_block_info* info) { - const String::Language fragment_lang=(String::Language)alang; + const String::Language fragment_lang=(String::Language)(unsigned char)alang; bool& whitespace=info->whitespace; size_t fragment_end=info->fragment_begin+fragment_length; - //fprintf(stderr, "%d, %d\n", fragment.lang, fragment.length); - + //fprintf(stderr, "%d, %d =%s=\n", fragment_lang, fragment_length, info->body->cstr()); - String::Language to_lang=info->lang==String::Language::L_UNSPECIFIED?fragment_lang:info->lang; - bool optimize=(to_lang & String::Language::L_OPTIMIZE_BIT)!=0; + String::Language to_lang=info->lang==String::L_UNSPECIFIED?fragment_lang:info->lang; + bool optimize=(to_lang & String::L_OPTIMIZE_BIT)!=0; if(!optimize) whitespace=false; - switch(to_lang & ~String::Language::L_OPTIMIZE_BIT) { - case String::Language::L_CLEAN: - case String::Language::L_TAINTED: - case String::Language::L_AS_IS: + switch(to_lang & ~String::L_OPTIMIZE_BIT) { + case String::L_CLEAN: + case String::L_TAINTED: + case String::L_AS_IS: // clean piece // tainted piece, but undefined untaint language @@ -346,18 +325,21 @@ int cstr_to_string_body_block(char alang // tainted, untaint language: as-is ec_append(info->result, optimize, whitespace, info->pos, fragment_length); break; - case String::Language::L_FILE_SPEC: + case String::L_FILE_SPEC: // tainted, untaint language: file [name] - escape( - // Macintosh has problems with small Russian letter 'r' - if( c=='\xF0' && info->charsets && info->charsets->source().NAME()=="WINDOWS-1251" ) { - // fixing that letter for most common charset - to_char('p'); - } else // fallback to default - encode(need_file_encode, '_', c); - ); + { + bool is1251=(info->charsets && info->charsets->source().NAME()=="WINDOWS-1251"); + escape_fragment( + // Macintosh has problems with small Russian letter 'r' + if( is1251 && c=='\xF0' ) { + // fixing that letter for most common charset + to_char('p'); + } else // fallback to default + encode(need_file_encode, '_', c); + ); + } break; - case String::Language::L_URI: + case String::L_URI: // tainted, untaint language: uri { const char *fragment_str=info->body->mid(info->fragment_begin, fragment_length).cstr(); @@ -370,17 +352,18 @@ int cstr_to_string_body_block(char alang info->charsets->client()); char c; - for(const char* src=output.str; c=*src++; ) + for(const char* src=output.str; (c=*src++); ) encode(need_uri_encode, '%', c); } break; - case String::Language::L_HTTP_HEADER: + case String::L_HTTP_HEADER: // tainted, untaint language: http-field-content-text - escape( + // the same as L_URI BUT not transcoded into $response:charset before encoding + escape_fragment( encode(need_uri_encode, '%', c); ); break; - case String::Language::L_MAIL_HEADER: + case String::L_MAIL_HEADER: // tainted, untaint language: mail-header // http://www.ietf.org/rfc/rfc2047.txt if(info->charsets) { @@ -397,13 +380,15 @@ int cstr_to_string_body_block(char alang bool email=false; uchar c; - for(const char* src=mail_ptr; c=(uchar)*src++; ) { - //RFC + An 'encoded-word' MUST NOT appear in any portion of an 'addr-spec'. - if(to_quoted_printable && (c==',' || addr_spec_soon(src) || c == '"')) { + for(const char* src=mail_ptr; (c=(uchar)*src++); ) { + if(c=='\r' || c=='\n') + c=' '; + if(to_quoted_printable && (c==',' || c == '"' || addr_spec_soon(src-1/*position to 'c'*/))) { email=c=='<'; to_string("?="); to_quoted_printable=false; } + //RFC + An 'encoded-word' MUST NOT appear in any portion of an 'addr-spec'. if(!email && ( !to_quoted_printable && (c & 0x80) // starting quote-printable-encoding on first 8bit char || to_quoted_printable && !mail_header_char_valid_within_Qencoded(c) @@ -426,16 +411,7 @@ int cstr_to_string_body_block(char alang } else ec_append(info->result, optimize, whitespace, info->pos, fragment_length); break; - case String::Language::L_TABLE: - // tainted, untaint language: table - escape(switch(c) { - case '\t': to_char(' '); break; - case '\n': to_char(' '); break; - _default; - }); - break; -#ifdef PA_SQL - case String::Language::L_SQL: + case String::L_SQL: // tainted, untaint language: sql if(info->connection) { const char *fragment_str=info->body->mid(info->fragment_begin, fragment_length).cstr(); @@ -443,43 +419,88 @@ int cstr_to_string_body_block(char alang pa_CORD_pos_advance(info->pos, fragment_length); to_string(info->connection->quote(fragment_str, fragment_length)); - } else - throw Exception(0, - 0, - "untaint in SQL language failed - no connection specified"); + } else { + info->exception="untaint in SQL language failed - no connection specified"; + info->fragment_begin=fragment_end; + return 1; // stop processing. can't throw exception here + } break; -#endif - case String::Language::L_JS: - escape(switch(c) { + case String::L_JS: + escape_fragment(switch(c) { + case '\n': to_string("\\n"); break; case '"': to_string("\\\""); break; case '\'': to_string("\\'"); break; - case '\n': to_string("\\n"); break; case '\\': to_string("\\\\"); break; case '\xFF': to_string("\\\xFF"); break; - _default; + default: _default; break; }); break; - case String::Language::L_XML: - escape(switch(c) { + case String::L_XML: + // [2] Char ::= #x9 | #xA | #xD | [#x20-#xD7FF] | [#xE000-#xFFFD] | [#x10000-#x10FFFF] + escape_fragment(switch(c) { + case '\x20': + case '\x9': + case '\xA': + case '\xD': // this is usually removed on input + _default; + break; case '&': to_string("&"); break; case '>': to_string(">"); break; case '<': to_string("<"); break; case '"': to_string("""); break; case '\'': to_string("'"); break; - _default; + default: + if(((unsigned char)c)<0x20) { + // fixing it, so that libxml would not result + // in fatal error parsing text + // though it really violates standard. + // to indicate there were an error + // replace bad char not to it's code, + // which we can do, + // but rather to '!' to show that input were actually + // invalid. + // life: shows that MSIE can somehow garble form values + // so that they contain these chars. + to_char('!'); + } else { + _default; + } + break; }); break; - case String::Language::L_HTML: - escape(switch(c) { + case String::L_HTML: + escape_fragment(switch(c) { case '&': to_string("&"); break; case '>': to_string(">"); break; case '<': to_string("<"); break; case '"': to_string("""); break; - _default; + default: _default; break; }); break; + case String::L_REGEX: + // tainted, untaint language: regex + escape_fragment( + if(need_regex_escape(c)) + to_char('\\') + _default; + ); + break; + case String::L_HTTP_COOKIE: + // tainted, untaint language: cookie (3.3.0 and higher: %uXXXX in UTF-8) + { + const char *fragment_str=info->body->mid(info->fragment_begin, fragment_length).cstr(); + // skip source [we use recoded version] + pa_CORD_pos_advance(info->pos, fragment_length); + String::C output(fragment_str, fragment_length); + + output=Charset::escape(output, info->charsets->source()); + //throw Exception(0, 0, output); + to_string(output); + + } + break; default: - SAPI::die("unknown untaint language #%d", + SAPI::abort("unknown untaint language #%d", static_cast(to_lang)); // should never break; // never } @@ -490,9 +511,11 @@ int cstr_to_string_body_block(char alang } -StringBody String::cstr_to_string_body(Language lang, +String::Body String::cstr_to_string_body(Language lang, SQL_Connection* connection, const Request_charsets *charsets) const { + if(is_empty()) + return String::Body(); Cstr_to_string_body_block_info info; // input @@ -505,9 +528,15 @@ StringBody String::cstr_to_string_body(L // private body.set_pos(info.pos, 0); info.fragment_begin=0; + info.exception=0; info.whitespace=true; - + langs.for_each(body, cstr_to_string_body_block, &info); + if(info.exception){ + throw Exception(0, + 0, + info.exception); + } - return StringBody(CORD_ec_to_cord(info.result)); + return String::Body(CORD_ec_to_cord(info.result)); }