Commit message: Prevent fts5 tokenizer unicode61 from considering '\0' to be a token characters, even if other characters of class "Cc" are.

FossilOrigin-Name: b7b7bde9b7a03665e3691c6d51118965f216d2dfb1617f138b9f9e60e418ed2f
CVE: CVE-2021-20223
CWE: CWE-787
Vulnerability description: Rejected reason: DO NOT USE THIS CANDIDATE NUMBER. ConsultIDs: none. Reason: This candidate was withdrawn by its CNA. Further investigation showed that it was not a security issue. Notes: none.

Project: sqlite
File: fts5_unicode2.c

int sqlite3Fts5UnicodeCategory(u32 iCode) { 
  int iRes = -1;
  int iHi;
  int iLo;
  int ret;
  u16 iKey;

  if( iCode>=(1<<20) ){
    return 0;
  }
  iLo = aFts5UnicodeBlock[(iCode>>16)];
  iHi = aFts5UnicodeBlock[1+(iCode>>16)];
  iKey = (iCode & 0xFFFF);
  while( iHi>iLo ){
    int iTest = (iHi + iLo) / 2;
    assert( iTest>=iLo && iTest<iHi );
    if( iKey>=aFts5UnicodeMap[iTest] ){
      iRes = iTest;
      iLo = iTest+1;
    }else{
      iHi = iTest;
    }
  }

  if( iRes<0 ) return 0;
  if( iKey>=(aFts5UnicodeMap[iRes]+(aFts5UnicodeData[iRes]>>5)) ) return 0;
  ret = aFts5UnicodeData[iRes] & 0x1F;
  if( ret!=30 ) return ret;
  return ((iKey - aFts5UnicodeMap[iRes]) & 0x01) ? 5 : 9;
}

Project: sqlite
File: fts5_unicode2.c

static int fts5_remove_diacritic(int c, int bComplex){
  unsigned short aDia[] = {
        0,  1797,  1848,  1859,  1891,  1928,  1940,  1995, 
     2024,  2040,  2060,  2110,  2168,  2206,  2264,  2286, 
     2344,  2383,  2472,  2488,  2516,  2596,  2668,  2732, 
     2782,  2842,  2894,  2954,  2984,  3000,  3028,  3336, 
     3456,  3696,  3712,  3728,  3744,  3766,  3832,  3896, 
     3912,  3928,  3944,  3968,  4008,  4040,  4056,  4106, 
     4138,  4170,  4202,  4234,  4266,  4296,  4312,  4344, 
     4408,  4424,  4442,  4472,  4488,  4504,  6148,  6198, 
     6264,  6280,  6360,  6429,  6505,  6529, 61448, 61468, 
    61512, 61534, 61592, 61610, 61642, 61672, 61688, 61704, 
    61726, 61784, 61800, 61816, 61836, 61880, 61896, 61914, 
    61948, 61998, 62062, 62122, 62154, 62184, 62200, 62218, 
    62252, 62302, 62364, 62410, 62442, 62478, 62536, 62554, 
    62584, 62604, 62640, 62648, 62656, 62664, 62730, 62766, 
    62830, 62890, 62924, 62974, 63032, 63050, 63082, 63118, 
    63182, 63242, 63274, 63310, 63368, 63390, 
  };
#define HIBIT ((unsigned char)0x80)
  unsigned char aChar[] = {
    '\0',      'a',       'c',       'e',       'i',       'n',       
    'o',       'u',       'y',       'y',       'a',       'c',       
    'd',       'e',       'e',       'g',       'h',       'i',       
    'j',       'k',       'l',       'n',       'o',       'r',       
    's',       't',       'u',       'u',       'w',       'y',       
    'z',       'o',       'u',       'a',       'i',       'o',       
    'u',       'u'|HIBIT, 'a'|HIBIT, 'g',       'k',       'o',       
    'o'|HIBIT, 'j',       'g',       'n',       'a'|HIBIT, 'a',       
    'e',       'i',       'o',       'r',       'u',       's',       
    't',       'h',       'a',       'e',       'o'|HIBIT, 'o',       
    'o'|HIBIT, 'y',       '\0',      '\0',      '\0',      '\0',      
    '\0',      '\0',      '\0',      '\0',      'a',       'b',       
    'c'|HIBIT, 'd',       'd',       'e'|HIBIT, 'e',       'e'|HIBIT, 
    'f',       'g',       'h',       'h',       'i',       'i'|HIBIT, 
    'k',       'l',       'l'|HIBIT, 'l',       'm',       'n',       
    'o'|HIBIT, 'p',       'r',       'r'|HIBIT, 'r',       's',       
    's'|HIBIT, 't',       'u',       'u'|HIBIT, 'v',       'w',       
    'w',       'x',       'y',       'z',       'h',       't',       
    'w',       'y',       'a',       'a'|HIBIT, 'a'|HIBIT, 'a'|HIBIT, 
    'e',       'e'|HIBIT, 'e'|HIBIT, 'i',       'o',       'o'|HIBIT, 
    'o'|HIBIT, 'o'|HIBIT, 'u',       'u'|HIBIT, 'u'|HIBIT, 'y',       
  };

  unsigned int key = (((unsigned int)c)<<3) | 0x00000007;
  int iRes = 0;
  int iHi = sizeof(aDia)/sizeof(aDia[0]) - 1;
  int iLo = 0;
  while( iHi>=iLo ){
    int iTest = (iHi + iLo) / 2;
    if( key >= aDia[iTest] ){
      iRes = iTest;
      iLo = iTest+1;
    }else{
      iHi = iTest-1;
    }
  }
  assert( key>=aDia[iRes] );
  if( bComplex==0 && (aChar[iRes] & 0x80) ) return c;
  return (c > (aDia[iRes]>>3) + (aDia[iRes]&0x07)) ? c : ((int)aChar[iRes] & 0x7F);
}

Project: sqlite
File: fts5_unicode2.c

int sqlite3Fts5UnicodeFold(int c, int eRemoveDiacritic){
  /* Each entry in the following array defines a rule for folding a range
  ** of codepoints to lower case. The rule applies to a range of nRange
  ** codepoints starting at codepoint iCode.
  **
  ** If the least significant bit in flags is clear, then the rule applies
  ** to all nRange codepoints (i.e. all nRange codepoints are upper case and
  ** need to be folded). Or, if it is set, then the rule only applies to
  ** every second codepoint in the range, starting with codepoint C.
  **
  ** The 7 most significant bits in flags are an index into the aiOff[]
  ** array. If a specific codepoint C does require folding, then its lower
  ** case equivalent is ((C + aiOff[flags>>1]) & 0xFFFF).
  **
  ** The contents of this array are generated by parsing the CaseFolding.txt
  ** file distributed as part of the "Unicode Character Database". See
  ** http://www.unicode.org for details.
  */
  static const struct TableEntry {
    unsigned short iCode;
    unsigned char flags;
    unsigned char nRange;
  } aEntry[] = {
    {65, 14, 26},          {181, 64, 1},          {192, 14, 23},
    {216, 14, 7},          {256, 1, 48},          {306, 1, 6},
    {313, 1, 16},          {330, 1, 46},          {376, 116, 1},
    {377, 1, 6},           {383, 104, 1},         {385, 50, 1},
    {386, 1, 4},           {390, 44, 1},          {391, 0, 1},
    {393, 42, 2},          {395, 0, 1},           {398, 32, 1},
    {399, 38, 1},          {400, 40, 1},          {401, 0, 1},
    {403, 42, 1},          {404, 46, 1},          {406, 52, 1},
    {407, 48, 1},          {408, 0, 1},           {412, 52, 1},
    {413, 54, 1},          {415, 56, 1},          {416, 1, 6},
    {422, 60, 1},          {423, 0, 1},           {425, 60, 1},
    {428, 0, 1},           {430, 60, 1},          {431, 0, 1},
    {433, 58, 2},          {435, 1, 4},           {439, 62, 1},
    {440, 0, 1},           {444, 0, 1},           {452, 2, 1},
    {453, 0, 1},           {455, 2, 1},           {456, 0, 1},
    {458, 2, 1},           {459, 1, 18},          {478, 1, 18},
    {497, 2, 1},           {498, 1, 4},           {502, 122, 1},
    {503, 134, 1},         {504, 1, 40},          {544, 110, 1},
    {546, 1, 18},          {570, 70, 1},          {571, 0, 1},
    {573, 108, 1},         {574, 68, 1},          {577, 0, 1},
    {579, 106, 1},         {580, 28, 1},          {581, 30, 1},
    {582, 1, 10},          {837, 36, 1},          {880, 1, 4},
    {886, 0, 1},           {902, 18, 1},          {904, 16, 3},
    {908, 26, 1},          {910, 24, 2},          {913, 14, 17},
    {931, 14, 9},          {962, 0, 1},           {975, 4, 1},
    {976, 140, 1},         {977, 142, 1},         {981, 146, 1},
    {982, 144, 1},         {984, 1, 24},          {1008, 136, 1},
    {1009, 138, 1},        {1012, 130, 1},        {1013, 128, 1},
    {1015, 0, 1},          {1017, 152, 1},        {1018, 0, 1},
    {1021, 110, 3},        {1024, 34, 16},        {1040, 14, 32},
    {1120, 1, 34},         {1162, 1, 54},         {1216, 6, 1},
    {1217, 1, 14},         {1232, 1, 88},         {1329, 22, 38},
    {4256, 66, 38},        {4295, 66, 1},         {4301, 66, 1},
    {7680, 1, 150},        {7835, 132, 1},        {7838, 96, 1},
    {7840, 1, 96},         {7944, 150, 8},        {7960, 150, 6},
    {7976, 150, 8},        {7992, 150, 8},        {8008, 150, 6},
    {8025, 151, 8},        {8040, 150, 8},        {8072, 150, 8},
    {8088, 150, 8},        {8104, 150, 8},        {8120, 150, 2},
    {8122, 126, 2},        {8124, 148, 1},        {8126, 100, 1},
    {8136, 124, 4},        {8140, 148, 1},        {8152, 150, 2},
    {8154, 120, 2},        {8168, 150, 2},        {8170, 118, 2},
    {8172, 152, 1},        {8184, 112, 2},        {8186, 114, 2},
    {8188, 148, 1},        {8486, 98, 1},         {8490, 92, 1},
    {8491, 94, 1},         {8498, 12, 1},         {8544, 8, 16},
    {8579, 0, 1},          {9398, 10, 26},        {11264, 22, 47},
    {11360, 0, 1},         {11362, 88, 1},        {11363, 102, 1},
    {11364, 90, 1},        {11367, 1, 6},         {11373, 84, 1},
    {11374, 86, 1},        {11375, 80, 1},        {11376, 82, 1},
    {11378, 0, 1},         {11381, 0, 1},         {11390, 78, 2},
    {11392, 1, 100},       {11499, 1, 4},         {11506, 0, 1},
    {42560, 1, 46},        {42624, 1, 24},        {42786, 1, 14},
    {42802, 1, 62},        {42873, 1, 4},         {42877, 76, 1},
    {42878, 1, 10},        {42891, 0, 1},         {42893, 74, 1},
    {42896, 1, 4},         {42912, 1, 10},        {42922, 72, 1},
    {65313, 14, 26},       
  };
  static const unsigned short aiOff[] = {
   1,     2,     8,     15,    16,    26,    28,    32,    
   37,    38,    40,    48,    63,    64,    69,    71,    
   79,    80,    116,   202,   203,   205,   206,   207,   
   209,   210,   211,   213,   214,   217,   218,   219,   
   775,   7264,  10792, 10795, 23228, 23256, 30204, 54721, 
   54753, 54754, 54756, 54787, 54793, 54809, 57153, 57274, 
   57921, 58019, 58363, 61722, 65268, 65341, 65373, 65406, 
   65408, 65410, 65415, 65424, 65436, 65439, 65450, 65462, 
   65472, 65476, 65478, 65480, 65482, 65488, 65506, 65511, 
   65514, 65521, 65527, 65528, 65529, 
  };

  int ret = c;

  assert( sizeof(unsigned short)==2 && sizeof(unsigned char)==1 );

  if( c<128 ){
    if( c>='A' && c<='Z' ) ret = c + ('a' - 'A');
  }else if( c<65536 ){
    const struct TableEntry *p;
    int iHi = sizeof(aEntry)/sizeof(aEntry[0]) - 1;
    int iLo = 0;
    int iRes = -1;

    assert( c>aEntry[0].iCode );
    while( iHi>=iLo ){
      int iTest = (iHi + iLo) / 2;
      int cmp = (c - aEntry[iTest].iCode);
      if( cmp>=0 ){
        iRes = iTest;
        iLo = iTest+1;
      }else{
        iHi = iTest-1;
      }
    }

    assert( iRes>=0 && c>=aEntry[iRes].iCode );
    p = &aEntry[iRes];
    if( c<(p->iCode + p->nRange) && 0==(0x01 & p->flags & (p->iCode ^ c)) ){
      ret = (c + (aiOff[p->flags>>1])) & 0x0000FFFF;
      assert( ret>0 );
    }

    if( eRemoveDiacritic ){
      ret = fts5_remove_diacritic(ret, eRemoveDiacritic==2);
    }
  }
  
  else if( c>=66560 && c<66600 ){
    ret = c + 40;
  }

  return ret;
}

Project: sqlite
File: fts5_unicode2.c

void sqlite3Fts5UnicodeAscii(u8 *aArray, u8 *aAscii){
  int i = 0;
  int iTbl = 0;
  while( i<128 ){
    int bToken = aArray[ aFts5UnicodeData[iTbl] & 0x1F ];
    int n = (aFts5UnicodeData[iTbl] >> 5) + i;
    for(; i<128 && i<n; i++){
      aAscii[i] = (u8)bToken;
    }
    iTbl++;
  }
  aAscii[0] = 0;                  /* 0x00 is never a token character */
}

Project: sqlite
File: fts5_unicode2.c

int sqlite3Fts5UnicodeIsdiacritic(int c){
  unsigned int mask0 = 0x08029FDF;
  unsigned int mask1 = 0x000361F8;
  if( c<768 || c>817 ) return 0;
  return (c < 768+32) ?
      (mask0 & ((unsigned int)1 << (c-768))) :
      (mask1 & ((unsigned int)1 << (c-768-32)));
}

Project: sqlite
File: fts5_unicode2.c

int sqlite3Fts5UnicodeCatParse(const char *zCat, u8 *aArray){ 
  aArray[0] = 1;
  switch( zCat[0] ){
    case 'C':
          switch( zCat[1] ){
            case 'c': aArray[1] = 1; break;
            case 'f': aArray[2] = 1; break;
            case 'n': aArray[3] = 1; break;
            case 's': aArray[4] = 1; break;
            case 'o': aArray[31] = 1; break;
            case '*': 
              aArray[1] = 1;
              aArray[2] = 1;
              aArray[3] = 1;
              aArray[4] = 1;
              aArray[31] = 1;
              break;
            default: return 1;          }
          break;

    case 'L':
          switch( zCat[1] ){
            case 'l': aArray[5] = 1; break;
            case 'm': aArray[6] = 1; break;
            case 'o': aArray[7] = 1; break;
            case 't': aArray[8] = 1; break;
            case 'u': aArray[9] = 1; break;
            case 'C': aArray[30] = 1; break;
            case '*': 
              aArray[5] = 1;
              aArray[6] = 1;
              aArray[7] = 1;
              aArray[8] = 1;
              aArray[9] = 1;
              aArray[30] = 1;
              break;
            default: return 1;          }
          break;

    case 'M':
          switch( zCat[1] ){
            case 'c': aArray[10] = 1; break;
            case 'e': aArray[11] = 1; break;
            case 'n': aArray[12] = 1; break;
            case '*': 
              aArray[10] = 1;
              aArray[11] = 1;
              aArray[12] = 1;
              break;
            default: return 1;          }
          break;

    case 'N':
          switch( zCat[1] ){
            case 'd': aArray[13] = 1; break;
            case 'l': aArray[14] = 1; break;
            case 'o': aArray[15] = 1; break;
            case '*': 
              aArray[13] = 1;
              aArray[14] = 1;
              aArray[15] = 1;
              break;
            default: return 1;          }
          break;

    case 'P':
          switch( zCat[1] ){
            case 'c': aArray[16] = 1; break;
            case 'd': aArray[17] = 1; break;
            case 'e': aArray[18] = 1; break;
            case 'f': aArray[19] = 1; break;
            case 'i': aArray[20] = 1; break;
            case 'o': aArray[21] = 1; break;
            case 's': aArray[22] = 1; break;
            case '*': 
              aArray[16] = 1;
              aArray[17] = 1;
              aArray[18] = 1;
              aArray[19] = 1;
              aArray[20] = 1;
              aArray[21] = 1;
              aArray[22] = 1;
              break;
            default: return 1;          }
          break;

    case 'S':
          switch( zCat[1] ){
            case 'c': aArray[23] = 1; break;
            case 'k': aArray[24] = 1; break;
            case 'm': aArray[25] = 1; break;
            case 'o': aArray[26] = 1; break;
            case '*': 
              aArray[23] = 1;
              aArray[24] = 1;
              aArray[25] = 1;
              aArray[26] = 1;
              break;
            default: return 1;          }
          break;

    case 'Z':
          switch( zCat[1] ){
            case 'l': aArray[27] = 1; break;
            case 'p': aArray[28] = 1; break;
            case 's': aArray[29] = 1; break;
            case '*': 
              aArray[27] = 1;
              aArray[28] = 1;
              aArray[29] = 1;
              break;
            default: return 1;          }
          break;

  }
  return 0;
}