/* *************************************************************************** * Copyright (C) 2008-2013, International Business Machines Corporation * and others. All Rights Reserved. *************************************************************************** * * uspoof_impl.h * * Implemenation header for spoof detection * */ #ifndef USPOOFIM_H #define USPOOFIM_H #include "unicode/utypes.h" #include "unicode/uspoof.h" #include "unicode/uscript.h" #include "unicode/udata.h" #include "utrie2.h" #if !UCONFIG_NO_NORMALIZATION #ifdef __cplusplus U_NAMESPACE_BEGIN // The maximium length (in UTF-16 UChars) of the skeleton replacement string resulting from // a single input code point. This is function of the unicode.org data. #define USPOOF_MAX_SKELETON_EXPANSION 20 // The default stack buffer size for copies or conversions or normalizations // of input strings being checked. (Used in multiple places.) #define USPOOF_STACK_BUFFER_SIZE 100 // Magic number for sanity checking spoof data. #define USPOOF_MAGIC 0x3845fdef class IdentifierInfo; class ScriptSet; class SpoofData; struct SpoofDataHeader; struct SpoofStringLengthsElement; /** * Class SpoofImpl corresponds directly to the plain C API opaque type * USpoofChecker. One can be cast to the other. */ class SpoofImpl : public UObject { public: SpoofImpl(SpoofData *data, UErrorCode &status); SpoofImpl(); virtual ~SpoofImpl(); /** Copy constructor, used by the user level uspoof_clone() function. */ SpoofImpl(const SpoofImpl &src, UErrorCode &status); static SpoofImpl *validateThis(USpoofChecker *sc, UErrorCode &status); static const SpoofImpl *validateThis(const USpoofChecker *sc, UErrorCode &status); /** Get the confusable skeleton transform for a single code point. * The result is a string with a length between 1 and 18. * @param tableMask bit flag specifying which confusable table to use. * One of USPOOF_SL_TABLE_FLAG, USPOOF_MA_TABLE_FLAG, etc. * @return The length in UTF-16 code units of the substition string. */ int32_t confusableLookup(UChar32 inChar, int32_t tableMask, UnicodeString &destBuf) const; /** Set and Get AllowedLocales, implementations of the corresponding API */ void setAllowedLocales(const char *localesList, UErrorCode &status); const char * getAllowedLocales(UErrorCode &status); // Add (union) to the UnicodeSet all of the characters for the scripts used for // the specified locale. Part of the implementation of setAllowedLocales. void addScriptChars(const char *locale, UnicodeSet *allowedChars, UErrorCode &status); /** parse a hex number. Untility used by the builders. */ static UChar32 ScanHex(const UChar *s, int32_t start, int32_t limit, UErrorCode &status); // Implementation for Whole Script tests. // Return the test bit flag to be ORed into the eventual user return value // if a Spoof opportunity is detected. void wholeScriptCheck( const UnicodeString &text, ScriptSet *result, UErrorCode &status) const; static UClassID U_EXPORT2 getStaticClassID(void); virtual UClassID getDynamicClassID(void) const; // IdentifierInfo Cache. IdentifierInfo objects are somewhat expensive to create. // Maintain a one-element cache, which is sufficient to avoid repeatedly // creating new ones unless we get multi-thread concurrency in spoof // check operations, which should be statistically uncommon. IdentifierInfo *getIdentifierInfo(UErrorCode &status) const; void releaseIdentifierInfo(IdentifierInfo *idInfo) const; // // Data Members // int32_t fMagic; // Internal sanity check. int32_t fChecks; // Bit vector of checks to perform. SpoofData *fSpoofData; const UnicodeSet *fAllowedCharsSet; // The UnicodeSet of allowed characters. // for this Spoof Checker. Defaults to all chars. const char *fAllowedLocales; // The list of allowed locales. URestrictionLevel fRestrictionLevel; // The maximum restriction level for an acceptable identifier. IdentifierInfo *fCachedIdentifierInfo; // Do not use directly. See getIdentifierInfo().:w }; // // Confusable Mappings Data Structures // // For the confusable data, we are essentially implementing a map, // key: a code point // value: a string. Most commonly one char in length, but can be more. // // The keys are stored as a sorted array of 32 bit ints. // bits 0-23 a code point value // bits 24-31 flags // 24: 1 if entry applies to SL table // 25: 1 if entry applies to SA table // 26: 1 if entry applies to ML table // 27: 1 if entry applies to MA table // 28: 1 if there are multiple entries for this code point. // 29-30: length of value string, in UChars. // values are (1, 2, 3, other) // The key table is sorted in ascending code point order. (not on the // 32 bit int value, the flag bits do not participate in the sorting.) // // Lookup is done by means of a binary search in the key table. // // The corresponding values are kept in a parallel array of 16 bit ints. // If the value string is of length 1, it is literally in the value array. // For longer strings, the value array contains an index into the strings table. // // String Table: // The strings table contains all of the value strings (those of length two or greater) // concatentated together into one long UChar (UTF-16) array. // // The array is arranged by length of the strings - all strings of the same length // are stored together. The sections are ordered by length of the strings - // all two char strings first, followed by all of the three Char strings, etc. // // There is no nul character or other mark between adjacent strings. // // String Lengths table // The length of strings from 1 to 3 is flagged in the key table. // For strings of length 4 or longer, the string length table provides a // mapping between an index into the string table and the corresponding length. // Strings of these lengths are rare, so lookup time is not an issue. // Each entry consists of // uint16_t index of the _last_ string with this length // uint16_t the length // // Flag bits in the Key entries #define USPOOF_SL_TABLE_FLAG (1<<24) #define USPOOF_SA_TABLE_FLAG (1<<25) #define USPOOF_ML_TABLE_FLAG (1<<26) #define USPOOF_MA_TABLE_FLAG (1<<27) #define USPOOF_KEY_MULTIPLE_VALUES (1<<28) #define USPOOF_KEY_LENGTH_SHIFT 29 #define USPOOF_KEY_LENGTH_FIELD(x) (((x)>>29) & 3) struct SpoofStringLengthsElement { uint16_t fLastString; // index in string table of last string with this length uint16_t fStrLength; // Length of strings }; //------------------------------------------------------------------------------------- // // SpoofData // // A small class that wraps the raw (usually memory mapped) spoof data. // Serves two primary functions: // 1. Convenience. Contains real pointers to the data, to avoid dealing with // the offsets in the raw data. // 2. Reference counting. When a spoof checker is cloned, the raw data is shared // and must be retained until all checkers using the data are closed. // Nothing in this struct includes state that is specific to any particular // USpoofDetector object. // //--------------------------------------------------------------------------------------- class SpoofData: public UMemory { public: static SpoofData *getDefault(UErrorCode &status); // Load standard ICU spoof data. SpoofData(UErrorCode &status); // Create new spoof data wrapper. // Only used when building new data from rules. // Constructor for use when creating from prebuilt default data. // A UDataMemory is what the ICU internal data loading functions provide. // The udm is adopted by the SpoofData. SpoofData(UDataMemory *udm, UErrorCode &status); // Constructor for use when creating from serialized data. // SpoofData(const void *serializedData, int32_t length, UErrorCode &status); // Check raw Spoof Data Version compatibility. // Return TRUE it looks good. static UBool validateDataVersion(const SpoofDataHeader *rawData, UErrorCode &status); ~SpoofData(); // Destructor not normally used. // Use removeReference() instead. // Reference Counting functions. // Clone of a user-level spoof detector increments the ref count on the data. // Close of a user-level spoof detector decrements the ref count. // If the data is owned by us, it will be deleted when count goes to zero. SpoofData *addReference(); void removeReference(); // Reserve space in the raw data. For use by builder when putting together a // new set of data. Init the new storage to zero, to prevent inconsistent // results if it is not all otherwise set by the requester. // Return: // pointer to the new space that was added by this function. void *reserveSpace(int32_t numBytes, UErrorCode &status); // initialize the pointers from this object to the raw data. void initPtrs(UErrorCode &status); // Reset all fields to an initial state. // Called from the top of all constructors. void reset(); SpoofDataHeader *fRawData; // Ptr to the raw memory-mapped data UBool fDataOwned; // True if the raw data is owned, and needs // to be deleted when refcount goes to zero. UDataMemory *fUDM; // If not NULL, our data came from a // UDataMemory, which we must close when // we are done. uint32_t fMemLimit; // Limit of available raw data space u_atomic_int32_t fRefCount; // Confusable data int32_t *fCFUKeys; uint16_t *fCFUValues; SpoofStringLengthsElement *fCFUStringLengths; UChar *fCFUStrings; // Whole Script Confusable Data UTrie2 *fAnyCaseTrie; UTrie2 *fLowerCaseTrie; ScriptSet *fScriptSets; }; //--------------------------------------------------------------------------------------- // // Raw Binary Data Formats, as loaded from the ICU data file, // or as built by the builder. // //--------------------------------------------------------------------------------------- struct SpoofDataHeader { int32_t fMagic; // (0x3845fdef) uint8_t fFormatVersion[4]; // Data Format. Same as the value in struct UDataInfo // if there is one associated with this data. int32_t fLength; // Total lenght in bytes of this spoof data, // including all sections, not just the header. // The following four sections refer to data representing the confusable data // from the Unicode.org data from "confusables.txt" int32_t fCFUKeys; // byte offset to Keys table (from SpoofDataHeader *) int32_t fCFUKeysSize; // number of entries in keys table (32 bits each) // TODO: change name to fCFUValues, for consistency. int32_t fCFUStringIndex; // byte offset to String Indexes table int32_t fCFUStringIndexSize; // number of entries in String Indexes table (16 bits each) // (number of entries must be same as in Keys table int32_t fCFUStringTable; // byte offset of String table int32_t fCFUStringTableLen; // length of string table (in 16 bit UChars) int32_t fCFUStringLengths; // byte offset to String Lengths table int32_t fCFUStringLengthsSize; // number of entries in lengths table. (2 x 16 bits each) // The following sections are for data from confusablesWholeScript.txt int32_t fAnyCaseTrie; // byte offset to the serialized Any Case Trie int32_t fAnyCaseTrieLength; // Length (bytes) of the serialized Any Case Trie int32_t fLowerCaseTrie; // byte offset to the serialized Lower Case Trie int32_t fLowerCaseTrieLength; // Length (bytes) of the serialized Lower Case Trie int32_t fScriptSets; // byte offset to array of ScriptSets int32_t fScriptSetsLength; // Number of ScriptSets (24 bytes each) // The following sections are for data from xidmodifications.txt int32_t unused[15]; // Padding, Room for Expansion }; // // Structure for the Whole Script Confusable Data // See Unicode UAX-39, Unicode Security Mechanisms, for a description of the // Whole Script confusable data // // The data provides mappings from code points to a set of scripts // that contain characters that might be confused with the code point. // There are two mappings, one for lower case only, and one for characters // of any case. // // The actual data consists of a utrie2 to map from a code point to an offset, // and an array of UScriptSets (essentially bit maps) that is indexed // by the offsets obtained from the Trie. // // U_NAMESPACE_END #endif /* __cplusplus */ /** * Endianness swap function for binary spoof data. * @internal */ U_CAPI int32_t U_EXPORT2 uspoof_swap(const UDataSwapper *ds, const void *inData, int32_t length, void *outData, UErrorCode *status); #endif #endif /* USPOOFIM_H */