--- parser3/src/main/untaint.C 2001/03/12 21:54:20 1.2 +++ parser3/src/main/untaint.C 2003/01/29 11:55:22 1.115.2.4 @@ -1,120 +1,541 @@ -/* - Parser - Copyright (c) 2001 ArtLebedev Group (http://www.artlebedev.com) - Author: Alexander Petrosyan (http://design.ru/paf) +/** @file + Parser: String class part: untaint mechanizm. - $Id: untaint.C,v 1.2 2001/03/12 21:54:20 paf Exp $ + Copyright(c) 2001, 2003 ArtLebedev Group (http://www.artlebedev.com) + Author: Alexandr Petrosian (http://paf.design.ru) */ -#include +static const char* IDENT_UNTAINT_C="$Date: 2003/01/29 11:55:22 $"; #include "pa_pool.h" +#include "pa_value_includes.h" #include "pa_string.h" #include "pa_hash.h" #include "pa_exception.h" +#include "pa_table.h" +#include "pa_globals.h" +#include "pa_sql_connection.h" +#include "pa_dictionary.h" +#include "pa_common.h" +#include "pa_charset.h" +#include "pa_request_charsets.h" -#define escape(cases) \ +#define escape(action) \ { \ - const char *ptr=row->item.ptr; \ - int size=row->item.size; \ - for (;*ptr;ptr++) \ - switch(*ptr) { \ - cases \ - default: *copy_here++=*ptr; break; \ - } \ + const char *src=fragment->ptr; \ + for(int size=fragment->size; size--; src++) \ + action \ } -#define escape_value(a, c) case a: *copy_here++=c; break; -#define escape_subst(a, b, bsize) \ - case a: \ - { \ - strncpy(copy_here, b, bsize); \ - copy_here+=bsize; \ - } \ - break; +#define _default default: *dest++=*src; break +#define encode(need_encode_func, prefix) \ + if(need_encode_func(*src)) { \ + static const char *hex="0123456789ABCDEF"; \ + char chunk[3]={prefix}; \ + chunk[1]=hex[((unsigned char)*src)/0x10]; \ + chunk[2]=hex[((unsigned char)*src)%0x10]; \ + memcpy(dest, chunk, 3); dest+=3; \ + } else \ + *dest++=*src; \ + break +#define to_char(c) *dest++=c +#define to_string(b, bsize) \ + memcpy(dest, b, bsize); \ + dest+=bsize; \ + +inline bool need_file_encode(unsigned char c){ + // russian letters and space ENABLED + // encoding only these... + return strchr( + "*?'\"<>|" +#ifndef WIN32 + ":\\~" +#endif + , c)!=0; +} +inline bool need_uri_encode(unsigned char c){ + if((c>='0') &&(c<='9') ||(c>='A') &&(c<='Z') ||(c>='a') &&(c<='z')) + return false; + + return !strchr("_-./", c); +} +inline bool need_http_header_encode(unsigned char 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) +}; + // String -char *String::cstr() const { - char *result=(char *)malloc(size()*UNTAINT_TIMES_BIGGER+1); +/* + +HTTP-header = field-name ":" [ field-value ] CRLF + + field-name = token + field-value = *( field-content | LWS ) + + field-content = + + + +word = token | quoted-string + +token = 1* + + + +tspecials = "(" | ")" | "<" | ">" | "@" + | "," | ";" | ":" | "\" | <"> + | "/" | "[" | "]" | "?" | "=" + | "{" | "}" | SP | HT + +SP = +HT = + +LWS = [CRLF] 1*( SP | HT ) +TEXT = + +quoted-pair = "\" CHAR + + if(strchr("()<>@,;:\\\"/[]?={} \t", *ptr)) +*/ +inline bool need_quote_http_header(const char *ptr, size_t size) { + for(; size--; ptr++) + if(strchr(";\\\"= \t" /* excluded ()<>@, :/ ? []{} */, *ptr)) + return true; + return false; +} + +//#include "pa_sapi.h" +/** + appends to other String, + marking all tainted pieces of it with @a lang. + or marking ALL pieces of it with a @a lang when @a forced to, + and propagating OPTIMIZE language bit. +*/ +String& String::append_to(String& dest, uchar lang, bool forced) const { + if(is_empty()) + return dest; + + // without language-chage, small[fitting dest tail] string? + if(lang==UL_PASS_APPENDED && fused<=(dest.fallocated-dest.fused)) { + // felements[fused...]=src.felements[0..fused], fused+=src.fused + memcpy(&dest.felements[dest.fused], felements, sizeof(felements[0])*fused); + dest.fused+=fused; + return dest; + } + + // manually unrolled code to avoid do{if(const)} constructs + if(forced) + STRING_FOREACH_FRAGMENT( + dest.APPEND(fragment->ptr, fragment->size, + lang, //forcing passed lang + fragment->origin.file, fragment->origin.line); + ) + else if(lang==UL_PASS_APPENDED) + STRING_FOREACH_FRAGMENT( + dest.APPEND(fragment->ptr, fragment->size, + fragment->lang, // passing item's lang + fragment->origin.file, fragment->origin.line); + ) + else if(lang&UL_OPTIMIZE_BIT) // 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 + STRING_FOREACH_FRAGMENT( + dest.APPEND(fragment->ptr, fragment->size, + fragment->lang==UL_TAINTED?lang:( + fragment->lang==UL_CLEAN?UL_CLEAN|UL_OPTIMIZE_BIT: // ORing with OPTIMIZED flag + fragment->lang + ), + fragment->origin.file, fragment->origin.line); + ) + else + STRING_FOREACH_FRAGMENT( + dest.APPEND(fragment->ptr, fragment->size, + fragment->lang==UL_TAINTED?lang:fragment->lang, + fragment->origin.file, fragment->origin.line); + ); - char *copy_here=result; - const Chunk *chunk=&head; - // TODO: оптимизировать whitespaces для всех, кроме 'html' - do { - const Chunk::Row *row=chunk->rows; - for(int i=0; icount; i++) { - if(row==append_here) - goto break2; - - // WARNING: - // string can grow only UNTAINT_TIMES_BIGGER - switch(row->item.lang) { - case NO: - // clean piece - case YES: - // tainted piece, but undefined untaint language - // for VString.get_double of tainted values - // for ^process{body} evaluation - case AS_IS: - // tainted, untaint language: as-is - memcpy(copy_here, row->item.ptr, row->item.size); - copy_here+=row->item.size; - break; - case TABLE: - escape( - escape_value('\t', ' ') - escape_value('\n', ' ') - ); - break; - case SQL: - // tainted, untaint language: sql - // TODO: зависимость от sql сервера - memset(copy_here, '?', row->item.size); - copy_here+=row->item.size; - break; - case JS: - escape( - escape_subst('"', "\\\"", 2) - escape_subst('\'', "\\'", 2) - escape_subst('\n', "\\n", 2) - escape_subst('\r', "\\r", 2) - escape_subst('\\', "\\\\", 2) - escape_subst('я', "\\я", 2) - ); - break; - case HTML: - escape( - escape_subst('&', "&", 5) // BEFORE consequent relpaces yelding '&' - escape_subst('>', ">", 4) - escape_subst('<', "<",4) - escape_subst('"', """,6) - escape_value('\t', ' ') - //TODO: XSLT escape_subst('\'', "'", 6) - ); - break; - case HTML_TYPO: - // tainted, untaint language: html-typo - escape( - escape_subst('&', "&", 5) // BEFORE consequent relpaces yelding '&' - escape_subst('>', ">", 4) - escape_subst('<', "<",4) - escape_subst('"', """,6) - escape_value('\t', ' ') - //TODO: $MAIN:html-type table replace, max length(b)==UNTAINT_TIMES_BIGGER*length(a) - ); - break; - default: - THROW(0,0, - this, - "unknown untaint language #%d of %d piece", - static_cast(row->item.lang), - i); + return dest; +} + +size_t String::cstr_bufsize(Untaint_lang lang, + SQL_Connection *connection, + const Request_charsets *charsets) const { + size_t dest=1; // for terminating 0 + STRING_FOREACH_FRAGMENT( + uchar to_lang=lang==UL_UNSPECIFIED?fragment->lang:lang; + + switch(to_lang & ~UL_OPTIMIZE_BIT) { + case UL_CLEAN: + case UL_TAINTED: + case UL_AS_IS: + // clean piece + + // tainted piece, but undefined untaint language + // for VString.as_double of tainted values + // for ^process{body} evaluation + + // tainted, untaint language: as-is + dest+=fragment->size; + break; + case UL_FILE_SPEC: + // tainted, untaint language: file [name] + dest+=fragment->size*3/* worst: Z->%XX */; + break; + case UL_URI: + // tainted, untaint language: uri + dest+=fragment->size*6*3/* worst utf8 x worst Z->%XX */; + break; + case UL_HTTP_HEADER: + // tainted, untaint language: http-field-content-text + dest+=fragment->size*3/* worst: Z->%XX */; + break; + case UL_MAIL_HEADER: + // tainted, untaint language: mail-header + if(charsets) { + int parts_count=1; + const char *prev=fragment->ptr; + size_t size=fragment->size; + while(const char *comma_at=(const char*)memchr(prev, ',', size)) { + parts_count++; + size-=comma_at-prev; + prev=comma_at+1; + } + // Subject: Re: parser3: =?koi8-r?Q?=D3=C5=CD=C9=CE=C1=D2?= + dest+= + fragment->size*3+ + parts_count*(charsets->mail().name()->size()+MAX_STRING/* worst: =?charset?Q?=%XX?= */); + } else + dest+=fragment->size; + break; + case UL_TABLE: + // tainted, untaint language: table + dest+=fragment->size; + break; + case UL_SQL: + // tainted, untaint language: sql + if(connection) + dest+=connection->quote(0, fragment->ptr, fragment->size); + break; + case UL_JS: + escape(switch(*src) { + case '"': case '\'': case '\n': case '\\': case '\xFF': + dest+=2; break; + default: + dest++; break; + }); + break; + case UL_XML: + escape(switch(*src) { + case '&': case '>': case '<': case '"': case '\'': + dest+= 6; break; + default: + dest++; break; + }); + break; + case UL_HTML: + escape(switch(*src) { + case '&': + case '>': + case '<': + case '"': + dest+=6; break; + default: + dest++; break; + }); + break; + } + ); + return dest; +} + +/** http://www.ietf.org/rfc/rfc2047.txt +RFC +(3) As a replacement for a 'word' entity within a 'phrase', for example, + one that precedes an address in a From, To, or Cc header. The ABNF + definition for 'phrase' from RFC 822 thus becomes: + + phrase = 1*( encoded-word / word ) + + In this case the set of characters that may be used in a "Q"-encoded + 'encoded-word' is restricted to: . An 'encoded-word' that appears within a + 'phrase' MUST be separated from any adjacent 'word', 'text' or + 'special' by 'linear-white-space'. +... + (2) The 8-bit hexadecimal value 20 (e.g., ISO-8859-1 SPACE) may be + represented as "_" (underscore, ASCII 95.). (This character may + not pass through some internetwork mail gateways, but its use + will greatly enhance readability of "Q" encoded data with mail + readers that do not support this encoding.) Note that the "_" + always represents hexadecimal 20, even if the SPACE character + occupies a different code position in the character set in use. + + paf: obviously, + without "=", or one could not differ "=E0" and "russian letter a" + and without "_", or in would mean 0x20 +*/ +static bool mail_header_char_valid_within_Qencoded(char c) { + return c>='A' && c<='Z' + || c>='a' && c<='Z' + || c>='0' && c<='9' + || strchr("!*+-/", c); +} +char *String::store_to(char *dest, Untaint_lang lang, + SQL_Connection *connection, + const Request_charsets *charsets) const { + // WARNING: + // before any changes check cstr_bufsize first!!! + bool whitespace=true; +// STRING_FOREACH_FRAGMENT( + element_type *last = felements+fused; element_type *fragment = felements; for(; fragmentlang:lang; + + char *start=dest; + + switch(to_lang & ~UL_OPTIMIZE_BIT) { + case UL_CLEAN: + case UL_TAINTED: + case UL_AS_IS: + // clean piece + + // tainted piece, but undefined untaint language + // for VString.as_double of tainted values + // for ^process{body} evaluation + + // tainted, untaint language: as-is + memcpy(dest, fragment->ptr, fragment->size); + dest+=fragment->size; + break; + case UL_FILE_SPEC: + // tainted, untaint language: file [name] + escape( + // Macintosh has problems with small Russian letter 'r' + if( *src=='\xF0' && charsets && *charsets->source().name()=="windows-1251" ) { + // fixing that letter for most common charset + to_char('p'); + } else // fallback to default + encode(need_file_encode, '_'); + ); + break; + case UL_URI: + // tainted, untaint language: uri + const void *client_ptr; + size_t client_size; + if(charsets) + Charset::transcode(charsets->pool(), + charsets->source(), fragment->ptr, fragment->size, + charsets->client(), client_ptr, client_size); + else { + client_ptr=fragment->ptr; + client_size=fragment->size; + } + + { + const char *src=(const char *)client_ptr; + for(int size=client_size; size--; src++) + encode(need_uri_encode, '%'); } - row++; + break; + case UL_HTTP_HEADER: + // tainted, untaint language: http-field-content-text + escape( + encode(need_uri_encode, '%'); + ); + break; + case UL_MAIL_HEADER: + // tainted, untaint language: mail-header + // http://www.ietf.org/rfc/rfc2047.txt + if(charsets) { + const void *mail_ptr; + size_t mail_size; + Charset::transcode(charsets->pool(), + charsets->source(), fragment->ptr, fragment->size, + charsets->mail(), mail_ptr, mail_size); + CharPtr charset_name=charsets->mail().name()->cstr(); + + // Subject: Re: parser3: =?koi8-r?Q?=D3=C5=CD=C9=CE=C1=D2?= + const char *src=(const char *)mail_ptr; + bool to_quoted_printable=false; + + bool email=false; + for(const char *end=src+mail_size; src') + email=false; + } + if(to_quoted_printable) // close + dest+=sprintf(dest, "?="); + + } else { + memcpy(dest, fragment->ptr, fragment->size); + dest+=fragment->size; + } + break; + case UL_TABLE: + // tainted, untaint language: table + escape(switch(*src) { + case '\t': to_char(' '); break; + case '\n': to_char(' '); break; + _default; + }); + break; + case UL_SQL: + // tainted, untaint language: sql + if(connection) + dest+=connection->quote(dest, fragment->ptr, fragment->size); + else + throw Exception(0, + ConstStringPtr(this), + "untaint in SQL language failed - no connection specified"); + break; + case UL_JS: + escape(switch(*src) { + case '"': to_string("\\\"", 2); break; + case '\'': to_string("\\'", 2); break; + case '\n': to_string("\\n", 2); break; + case '\\': to_string("\\\\", 2); break; + case '\xFF': to_string("\\\xFF", 2); break; + _default; + }); + break; + case UL_XML: + escape(switch(*src) { + case '&': to_string("&", 5); break; + case '>': to_string(">", 4); break; + case '<': to_string("<", 4); break; + case '"': to_string(""", 6); break; + case '\'': to_string("'", 6); break; + _default; + }); + break; + case UL_HTML: + escape(switch(*src) { + case '&': to_string("&", 5); break; + case '>': to_string(">", 4); break; + case '<': to_string("<", 4); break; + case '"': to_string(""", 6); break; + _default; + }); + break; + default: + throw Exception(0, + ConstStringPtr(this), + "unknown untaint language #%d", + static_cast(to_lang)); // should never + break; // never } - chunk=row->link; - } while(chunk); -break2: - *copy_here=0; + + if(to_lang & UL_OPTIMIZE_BIT) { + // optimizing whitespace + char *stop=dest; dest=start; + for(char *src=start; srcorigin.file) + dest+=sprintf(dest, ORIGIN_FILE_LINE_FORMAT, + fragment->origin.file, + 1+fragment->origin.line); + else + dest+=sprintf(dest, ""); +); + uchar show_lang=fragment->lang & ~UL_OPTIMIZE_BIT; + if(show_lang>=sizeof(String_Untaint_lang_name)/sizeof(String_Untaint_lang_name[0])) + throw Exception(0, + ConstStringPtr(this), + "unknown untaint language #%d", + static_cast(show_lang)); // sould never + + dest+=sprintf(dest, "#%s%s: ", + String_Untaint_lang_name[show_lang], + fragment->lang & UL_OPTIMIZE_BIT?".O":""); + char *dest_after_origins=dest; + + memcpy(dest, fragment->ptr, fragment->size); + dest+=fragment->size; + + remove_crlf(dest_after_origins, dest); + to_char('\n'); + ); + + *dest=0; return result; }