/**********************************************************************************
* C implementation of the zxcvbn password strength estimation method.
* Copyright (c) 2015, Tony Evans
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are
* permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this list
* of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice, this
* list of conditions and the following disclaimer in the documentation and/or other
* materials provided with the distribution.
*
* 3. Neither the name of the copyright holder nor the names of its contributors may be
* used to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
* SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
**********************************************************************************/
#include "zxcvbn.h"
#include <ctype.h>
#include <string.h>
#include <stdint.h>
#include <math.h>
#include <float.h>
#ifdef USE_DICT_FILE
#if defined(USE_FILE_IO) || !defined(__cplusplus)
#include <stdio.h>
#else
#include <fstream>
#endif
#endif
/* For pre-compiled headers under windows */
#ifdef _WIN32
#include "stdafx.h"
#endif
/*################################################################################*
*################################################################################*
* Begin utility function code
*################################################################################*
*################################################################################*/
/**********************************************************************************
* Binomial coefficient function. Uses method described at
* http://blog.plover.com/math/choose.html
*/
static double nCk(int n, int k)
{
int d;
double r;
if (k > n)
return 0.0;
if (!k)
return 1.0;
r = 1.0;
for(d = 1; d <= k; ++d)
{
r *= n--;
r /= d;
}
return r;
}
/**********************************************************************************
* Binary search function to find a character in a string.
* Parameters:
* Ch The character to find
* Ents The string to search
* NumEnts The number character groups in the string Ents
* SizeEnt The size of each character group.
* Returns a pointer to the found character, or null if not found.
*/
static const uint8_t *CharBinSearch(uint8_t Ch, const uint8_t *Ents, unsigned int NumEnts, unsigned int SizeEnt)
{
while(NumEnts > 0)
{
const uint8_t *Mid = Ents + (NumEnts >> 1) * SizeEnt;
int Dif = Ch - *Mid;
if (!Dif)
{
return Mid;
}
if (Dif > 0)
{
Ents = Mid + SizeEnt;
--NumEnts;
}
NumEnts /= 2;
}
return 0;
}
/**********************************************************************************
* Calculate potential number of different characters in the passed string.
* Parameters:
* Str The string of characters
* Len The maximum number of characters to scan
* Returns the potential number of different characters in the string.
*/
static int Cardinality(const uint8_t *Str, int Len)
{
int Card=0, Types=0;
int c;
while(Len > 0)
{
c = *Str++ & 0xFF;
if (!c)
break;
if (islower(c)) Types |= 1; /* Lowercase letter */
else if (isupper(c)) Types |= 2; /* Uppercase letter */
else if (isdigit(c)) Types |= 4; /* Numeric digit */
else if (c <= 0x7F) Types |= 8; /* Punctuation character */
else Types |= 16; /* Other (Unicode?) */
--Len;
}
if (Types & 1) Card += 26;
if (Types & 2) Card += 26;
if (Types & 4) Card += 10;
if (Types & 8) Card += 33;
if (Types & 16) Card += 100;
return Card;
}
/**********************************************************************************
* Allocate a ZxcMatch_t struct, clear it to zero
*/
static ZxcMatch_t *AllocMatch()
{
ZxcMatch_t *p = MallocFn(ZxcMatch_t, 1);
memset(p, 0, sizeof *p);
return p;
}
/**********************************************************************************
* Add new match struct to linked list of matches. List ordered with shortest at
* head of list.
*/
static void AddResult(ZxcMatch_t **HeadRef, ZxcMatch_t *Nu)
{
/* Find the correct insert point */
while(*HeadRef && ((*HeadRef)->Length < Nu->Length))
HeadRef = &((*HeadRef)->Next);
/* Add new entry or replace existing */
if (*HeadRef && ((*HeadRef)->Length == Nu->Length))
{
/* New entry has same length as existing, so one of them needs discarding */
if ((*HeadRef)->Entrpy <= Nu->Entrpy)
{
/* Existing entry has lower entropy - keep it, discard new entry */
FreeFn(Nu);
}
else
{
/* New entry has lower entropy - replace existing entry */
Nu->Next = (*HeadRef)->Next;
FreeFn(*HeadRef);
*HeadRef = Nu;
}
}
else
{
/* New entry has different length, so add it */
Nu->Next = *HeadRef;
*HeadRef = Nu;
}
}
/*################################################################################*
*################################################################################*
* Begin dictionary matching code
*################################################################################*
*################################################################################*/
#ifdef USE_DICT_FILE
/* Use dictionary data from file */
#if defined(USE_FILE_IO) || !defined(__cplusplus)
/* Use the FILE streams from stdio.h */
typedef FILE *FileHandle;
#define MyOpenFile(f, name) (f = fopen(name, "rb"))
#define MyReadFile(f, buf, bytes) (fread(buf, 1, bytes, f) == (bytes))
#define MyCloseFile(f) fclose(f)
#else
/* Use the C++ iostreams */
typedef std::ifstream FileHandle;
static inline void MyOpenFile(FileHandle & f, const char *Name)
{
f.open(Name, std::ifstream::in | std::ifstream::binary);
}
static inline bool MyReadFile(FileHandle & f, void *Buf, unsigned int Num)
{
return f.read((char *)Buf, Num);
}
static inline void MyCloseFile(FileHandle & f)
{
f.close();
}
#endif
/* Include file contains the CRC of the dictionary data file. Used to detect corruption */
/* of the file. */
#include "dict-crc.h"
#define MAX_DICT_FILE_SIZE (100+WORD_FILE_SIZE)
#define CHK_INIT 0xffffffffffffffffULL
/* Static table used for the crc implementation. */
static const uint64_t CrcTable[16] =
{
0x0000000000000000ULL, 0x7d08ff3b88be6f81ULL, 0xfa11fe77117cdf02ULL, 0x8719014c99c2b083ULL,
0xdf7adabd7a6e2d6fULL, 0xa2722586f2d042eeULL, 0x256b24ca6b12f26dULL, 0x5863dbf1e3ac9decULL,
0x95ac9329ac4bc9b5ULL, 0xe8a46c1224f5a634ULL, 0x6fbd6d5ebd3716b7ULL, 0x12b5926535897936ULL,
0x4ad64994d625e4daULL, 0x37deb6af5e9b8b5bULL, 0xb0c7b7e3c7593bd8ULL, 0xcdcf48d84fe75459ULL
};
static const unsigned int MAGIC = 'z' + ('x'<< 8) + ('c' << 16) + ('v' << 24);
static unsigned int NumNodes, NumChildLocs, NumRanks, NumChildMaps;
static unsigned int SizeChildMapEntry, NumLargeCounts, NumSmallCounts, SizeCharSet;
static unsigned int *DictNodes;
static unsigned short *ChildLocs;
static unsigned short *Ranks;
static uint8_t *ChildMap;
static uint8_t *EndCountLge;
static uint8_t *EndCountSml;
static uint8_t *CharSet;
/**********************************************************************************
* Calculate the CRC-64 of passed data.
* Parameters:
* Crc The initial or previous CRC value
* v Pointer to the data to add to CRC calculation
* Len Length of the passed data
* Returns the updated CRC value.
*/
static uint64_t CalcCrc64(uint64_t Crc, const void *v, unsigned int Len)
{
const uint8_t *Data = (const unsigned char *)v;
while(Len--)
{
Crc = CrcTable[(Crc ^ (*Data >> 0)) & 0x0f] ^ (Crc >> 4);
Crc = CrcTable[(Crc ^ (*Data >> 4)) & 0x0f] ^ (Crc >> 4);
++Data;
}
return Crc;
}
/**********************************************************************************
* Read the dictionary data from file.
* Parameters:
* Filename Name of the file to read.
* Returns 1 on success, 0 on error
*/
int ZxcvbnInit(const char *Filename)
{
FileHandle f;
uint64_t Crc = CHK_INIT;
if (DictNodes)
return 1;
MyOpenFile(f, Filename);
if (f)
{
unsigned int i, DictSize;
/* Get magic number */
if (!MyReadFile(f, &i, sizeof i))
i = 0;
/* Get header data */
if (!MyReadFile(f, &NumNodes, sizeof NumNodes))
i = 0;
if (!MyReadFile(f, &NumChildLocs, sizeof NumChildLocs))
i = 0;
if (!MyReadFile(f, &NumRanks, sizeof NumRanks))
i = 0;
if (!MyReadFile(f, &NumChildMaps, sizeof NumChildMaps))
i = 0;
if (!MyReadFile(f, &SizeChildMapEntry, sizeof SizeChildMapEntry))
i = 0;
if (!MyReadFile(f, &NumLargeCounts, sizeof NumLargeCounts))
i = 0;
if (!MyReadFile(f, &NumSmallCounts, sizeof NumSmallCounts))
i = 0;
if (!MyReadFile(f, &SizeCharSet, sizeof SizeCharSet))
i = 0;
/* Validate the header data */
if (NumNodes >= (1<<16))
i = 1;
if (NumChildLocs >= (1<<17))
i = 2;
if (NumChildMaps >= (1<<13))
i = 3;
if ((SizeChildMapEntry*8) < SizeCharSet)
i = 4;
if (NumLargeCounts >= (1<<8))
i = 5;
if (NumSmallCounts != NumNodes)
i = 6;
if (i != MAGIC)
{
MyCloseFile(f);
return 0;
}
Crc = CalcCrc64(Crc, &i, sizeof i);
Crc = CalcCrc64(Crc, &NumNodes, sizeof NumNodes);
Crc = CalcCrc64(Crc, &NumChildLocs, sizeof NumChildLocs);
Crc = CalcCrc64(Crc, &NumRanks, sizeof NumRanks);
Crc = CalcCrc64(Crc, &NumChildMaps, sizeof NumChildMaps);
Crc = CalcCrc64(Crc, &SizeChildMapEntry, sizeof SizeChildMapEntry);
Crc = CalcCrc64(Crc, &NumLargeCounts, sizeof NumLargeCounts);
Crc = CalcCrc64(Crc, &NumSmallCounts, sizeof NumSmallCounts);
Crc = CalcCrc64(Crc, &SizeCharSet, sizeof SizeCharSet);
DictSize = NumNodes*sizeof(unsigned int) + NumChildLocs*sizeof(unsigned short) + NumRanks*sizeof(unsigned short) +
NumChildMaps*SizeChildMapEntry + NumLargeCounts + NumSmallCounts + SizeCharSet;
if (DictSize < MAX_DICT_FILE_SIZE)
{
DictNodes = MallocFn(unsigned int, DictSize / sizeof(unsigned int) + 1);
if (!MyReadFile(f, DictNodes, DictSize))
{
FreeFn(DictNodes);
DictNodes = 0;
}
}
MyCloseFile(f);
if (!DictNodes)
return 0;
/* Check crc */
Crc = CalcCrc64(Crc, DictNodes, DictSize);
if (memcmp(&Crc, WordCheck, sizeof Crc))
{
/* File corrupted */
FreeFn(DictNodes);
DictNodes = 0;
return 0;
}
/* Set pointers to the data */
ChildLocs = (unsigned short *)(DictNodes + NumNodes);
Ranks = ChildLocs + NumChildLocs;
ChildMap = (unsigned char*)(Ranks + NumRanks);
EndCountLge = ChildMap + NumChildMaps*SizeChildMapEntry;
EndCountSml = EndCountLge + NumLargeCounts;
CharSet = EndCountSml + NumSmallCounts;
CharSet[SizeCharSet] = 0;
return 1;
}
return 0;
}
/**********************************************************************************
* Free the data allocated by ZxcvbnInit().
*/
void ZxcvbnUnInit()
{
if (DictNodes)
FreeFn(DictNodes);
DictNodes = 0;
}
#else
/* Include the source file containing the dictionary data */
#include "dict-src.h"
#endif
/**********************************************************************************
* Leet conversion strings
*/
/* String of normal chars that could be given as leet chars in the password */
static const uint8_t L33TChr[] = "abcegilostxz";
/* String of leet,normal,normal char triples. Used to convert supplied leet char to normal. */
static const uint8_t L33TCnv[] = "!i $s %x (c +t 0o 1il2z 3e 4a 5s 6g 7lt8b 9g <c @a [c {c |il";
#define LEET_NORM_MAP_SIZE 3
/* Struct holding additional data on the word match */
typedef struct
{
int Rank; /* Rank of word in dictionary */
int Caps; /* Number of capital letters */
int Lower; /* Number of lower case letters */
int NumLeet; /* Total number of leeted characters */
uint8_t Leeted[sizeof L33TChr]; /* Number of leeted chars for each char found in L33TChr */
uint8_t UnLeet[sizeof L33TChr]; /* Number of normal chars for each char found in L33TChr */
} DictMatchInfo_t;
/* Struct holding working data for the word match */
typedef struct
{
int StartLoc;
int Ordinal;
int PwdLength;
int Begin;
int Caps;
int Lower;
int NumPossChrs;
uint8_t Leeted[sizeof L33TChr];
uint8_t UnLeet[sizeof L33TChr];
uint8_t LeetCnv[sizeof L33TCnv / LEET_NORM_MAP_SIZE + 1];
/* uint8_t LeetChr[3]; */
uint8_t First;
uint8_t PossChars[48];
} DictWork_t;
/**********************************************************************************
* Given a map entry create a string of all possible characters for following to
* a child node
*/
static int ListPossibleChars(uint8_t *List, const uint8_t *Map)
{
unsigned int i, j, k;
int Len = 0;
for(k = i = 0; i < SizeChildMapEntry; ++i, ++Map)
{
if (!*Map)
{
k += 8;
continue;
}
for(j = 0; j < 8; ++j)
{
if (*Map & (1<<j))
{
*List++ = CharSet[k];
++Len;
}
++k;
}
}
*List=0;
return Len;
}
/**********************************************************************************
* Increment count of each char that could be leeted.
*/
static void AddLeetChr(uint8_t c, int IsLeet, uint8_t *Leeted, uint8_t *UnLeet)
{
const uint8_t *p = CharBinSearch(c, L33TChr, sizeof L33TChr - 1, 1);
if (p)
{
int i = p - L33TChr;
if (IsLeet > 0)
{
Leeted[i] += 1;
}
else if (IsLeet < 0)
{
Leeted[i] += 1;
UnLeet[i] -= 1;
}
else
{
UnLeet[i] += 1;
}
}
}
/**********************************************************************************
* Given details of a word match, update it with the entropy (as natural log of
* number of possiblities)
*/
static void DictionaryEntropy(ZxcMatch_t *m, DictMatchInfo_t *Extra, const uint8_t *Pwd)
{
double e = 0.0;
/* Add allowance for uppercase letters */
if (Extra->Caps)
{
if (Extra->Caps == m->Length)
{
/* All uppercase, common case so only 1 bit */
e += log(2.0);
}
else if ((Extra->Caps == 1) && (isupper(*Pwd) || isupper(Pwd[m->Length - 1])))
{
/* Only first or last uppercase, also common so only 1 bit */
e += log(2.0);
}
else
{
/* Get number of combinations of lowercase, uppercase letters */
int Up = Extra->Caps;
int Lo = Extra->Lower;
int i = Up;
if (i > Lo)
i = Lo;
for(Lo += Up; i >= 0; --i)
e += nCk(Lo, i);
if (e > 0.0)
e = log(e);
}
}
/* Add allowance for using leet substitution */
if (Extra->NumLeet)
{
int i;
double d = 0.0;
for(i = sizeof Extra->Leeted - 1; i >= 0; --i)
{
int Sb = Extra->Leeted[i];
if (Sb)
{
int Un = Extra->UnLeet[i];
int j = m->Length - Extra->NumLeet;
if ((j >= 0) && (Un > j))
Un = j;
j = Sb;
if (j > Un)
j = Un;
for(Un += Sb; j >= 0; --j)
{
double z = nCk(Un, j);
d += z;
}
}
}
if (d > 0.0)
d = log(d);
if (d < log(2.0))
d = log(2.0);
e += d;
/*if(zz)printf(",%f ", d/log(2.0)); */
}
/* Add entropy due to word's rank */
e += log((double)Extra->Rank);
m->Entrpy = e;
}
/**********************************************************************************
* Function that does the word matching
*/
static void DoDictMatch(const uint8_t *Passwd, int Start, int MaxLen, DictWork_t *Wrk, ZxcMatch_t **Result, DictMatchInfo_t *Extra, int Lev)
{
int Len;
uint8_t TempLeet[LEET_NORM_MAP_SIZE];
int Ord = Wrk->Ordinal;
int Caps = Wrk->Caps;
int Lower = Wrk->Lower;
int NodeLoc = Wrk->StartLoc;
uint8_t *PossChars = Wrk->PossChars;
int NumPossChrs = Wrk->NumPossChrs;
const uint8_t *Pwd = Passwd;
uint32_t NodeData = DictNodes[NodeLoc];
Passwd += Start;
for(Len = 0; *Passwd && (Len < MaxLen); ++Len, ++Passwd)
{
uint8_t c;
int w, x, y, z;
const uint8_t *q;
z = 0;
if (!Len && Wrk->First)
{
c = Wrk->First;
}
else
{
/* Get char and set of possible chars at current point in word. */
const uint8_t *Bmap;
c = *Passwd;
Bmap = ChildMap + (NodeData & ((1<<13)-1)) * SizeChildMapEntry;
NumPossChrs = ListPossibleChars(PossChars, Bmap);
/* Make it lowercase and update lowercase, uppercase counts */
if (isupper(c))
{
c = tolower(c);
++Caps;
}
else if (islower(c))
{
++Lower;
}
/* See if current char is a leet and can be converted */
q = CharBinSearch(c, L33TCnv, sizeof L33TCnv / LEET_NORM_MAP_SIZE, LEET_NORM_MAP_SIZE);
if (q)
{
/* Found, see if used before */
unsigned int j;
unsigned int i = (q - L33TCnv ) / LEET_NORM_MAP_SIZE;
if (Wrk->LeetCnv[i])
{
/* Used before, so limit characters to try */
TempLeet[0] = c;
TempLeet[1] = Wrk->LeetCnv[i];
TempLeet[2] = 0;
q = TempLeet;
}
for(j = 0; (*q > ' ') && (j < LEET_NORM_MAP_SIZE); ++j, ++q)
{
const uint8_t *r = CharBinSearch(*q, PossChars, NumPossChrs, 1);
if (r)
{
/* valid conversion from leet */
DictWork_t w;
w = *Wrk;
w.StartLoc = NodeLoc;
w.Ordinal = Ord;
w.PwdLength += Len;
w.Caps = Caps;
w.Lower = Lower;
w.First = *r;
w.NumPossChrs = NumPossChrs;
memcpy(w.PossChars, PossChars, sizeof w.PossChars);
if (j)
{
w.LeetCnv[i] = *r;
AddLeetChr(*r, -1, w.Leeted, w.UnLeet);
}
DoDictMatch(Pwd, Passwd - Pwd, MaxLen - Len, &w, Result, Extra, Lev+1);
}
}
return;
}
}
q = CharBinSearch(c, PossChars, NumPossChrs, 1);
if (q)
{
/* Found the char as a normal char */
if (CharBinSearch(c, L33TChr, sizeof L33TChr - 1, 1))
{
/* Char matches, but also a normal equivalent to a leet char */
AddLeetChr(c, 0, Wrk->Leeted, Wrk->UnLeet);
}
}
if (!q)
{
/* No match for char - return */
return;
}
/* Add all the end counts of the child nodes before the one that matches */
x = (q - Wrk->PossChars);
y = (NodeData >> 13) & ((1<<17)-1);
NodeLoc = ChildLocs[x+y];
for(w=0; w<x; ++w)
{
int Cloc = ChildLocs[w+y];
z = EndCountSml[Cloc];
if (DictNodes[Cloc] & (1<<31))
z += EndCountLge[Cloc]*256;
Ord += z;
}
/* Move to next node */
NodeData = DictNodes[NodeLoc];
if (NodeData & (1<<30))
{
/* Word matches, save result */
ZxcMatch_t *p;
Extra->Caps = Caps;
Extra->Rank = Ranks[Ord];
Extra->Lower = Lower;
for(x = 0, y = sizeof Extra->Leeted - 1; y >= 0; --y)
x += Wrk->Leeted[y];
Extra->NumLeet = x;
memcpy(Extra->UnLeet, Wrk->UnLeet, sizeof Extra->UnLeet);
memcpy(Extra->Leeted, Wrk->Leeted, sizeof Extra->Leeted);
p = AllocMatch();
if (x)
p->Type = DICT_LEET_MATCH;
else
p->Type = DICTIONARY_MATCH;
p->Length = Wrk->PwdLength + Len + 1;
p->Begin = Wrk->Begin;
DictionaryEntropy(p, Extra, Pwd);
AddResult(Result, p);
++Ord;
}
}
}
/**********************************************************************************
* Try to match password part with user supplied dictionary words
* Parameters:
* Result Pointer head of linked list used to store results
* Words Array of pointers to dictionary words
* Passwd The start of the password
* Start Where in the password to start attempting to match
* MaxLen Maximum number characters to consider
*/
static void UserMatch(ZxcMatch_t **Result, const char *Words[], const uint8_t *Passwd, int Start, int MaxLen)
{
int Rank;
if (!Words)
return;
Passwd += Start;
for(Rank = 0; Words[Rank]; ++Rank)
{
DictMatchInfo_t Extra;
uint8_t LeetChr[sizeof L33TCnv / LEET_NORM_MAP_SIZE + 1];
uint8_t TempLeet[3];
int Len = 0;
int Caps = 0;
int Lowers = 0;
int Leets = 0;
const uint8_t *Wrd = (const uint8_t *)(Words[Rank]);
const uint8_t *Pwd = Passwd;
memset(Extra.Leeted, 0, sizeof Extra.Leeted);
memset(Extra.UnLeet, 0, sizeof Extra.UnLeet);
memset(LeetChr, 0, sizeof LeetChr);
while(*Wrd)
{
const uint8_t *q;
uint8_t d = tolower(*Wrd++);
uint8_t c = *Pwd++;
if (isupper(c))
{
c = tolower(c);
++Caps;
}
else if (islower(c))
{
++Lowers;
}
/* See if current char is a leet and can be converted */
q = CharBinSearch(c, L33TCnv, sizeof L33TCnv / LEET_NORM_MAP_SIZE, LEET_NORM_MAP_SIZE);
if (q)
{
/* Found, see if used before */
unsigned int j;
unsigned int i = (q - L33TCnv ) / LEET_NORM_MAP_SIZE;
if (LeetChr[i])
{
/* Used before, so limit characters to try */
TempLeet[0] = c;
TempLeet[1] = LeetChr[i];
TempLeet[2] = 0;
q = TempLeet;
}
c = d+1;
for(j = 0; (*q > ' ') && (j < LEET_NORM_MAP_SIZE); ++j, ++q)
{
if (d == *q)
{
c = d;
if (i)
{
LeetChr[i] = c;
AddLeetChr(c, 1, Extra.Leeted, Extra.UnLeet);
++Leets;
}
break;
}
}
if (c != d)
{
Len = 0;
break;
}
}
else if (c == d)
{
/* Found the char as a normal char */
if (CharBinSearch(c, L33TChr, sizeof L33TChr - 1, 1))
{
/* Char matches, but also a normal equivalent to a leet char */
AddLeetChr(c, 0, Extra.Leeted, Extra.UnLeet);
}
}
else
{
/* No Match */
Len = 0;
break;
}
if (++Len > MaxLen)
{
Len = 0;
break;
}
}
if (Len)
{
ZxcMatch_t *p = AllocMatch();
if (!Leets)
p->Type = USER_MATCH;
else
p->Type = USER_LEET_MATCH;
p->Length = Len;
p->Begin = Start;
/* Add Entrpy */
Extra.Caps = Caps;
Extra.Lower = Lowers;
Extra.NumLeet = Leets;
Extra.Rank = Rank+1;
DictionaryEntropy(p, &Extra, Passwd);
AddResult(Result, p);
}
}
}
/**********************************************************************************
* Try to match password part with the dictionary words
* Parameters:
* Result Pointer head of linked list used to store results
* Passwd The start of the password
* Start Where in the password to start attempting to match
* MaxLen Maximum number characters to consider
*/
static void DictionaryMatch(ZxcMatch_t **Result, const uint8_t *Passwd, int Start, int MaxLen)
{
DictWork_t Wrk;
DictMatchInfo_t Extra;
memset(&Extra, 0, sizeof Extra);
memset(&Wrk, 0, sizeof Wrk);
Wrk.Ordinal = 1;
Wrk.StartLoc = ROOT_NODE_LOC;
Wrk.Begin = Start;
DoDictMatch(Passwd+Start, 0, MaxLen, &Wrk, Result, &Extra, 0);
}
/*################################################################################*
*################################################################################*
* Begin keyboard spatial sequence matching code
*################################################################################*
*################################################################################*/
#define MIN_SPATIAL_LEN 3
/* Struct to hold information on a keyboard layout */
typedef struct Keyboard
{
const uint8_t *Keys;
const uint8_t *Shifts;
int NumKeys;
int NumNear;
int NumShift;
int NumBlank;
} Keyboard_t;
/* Struct to hold information on the match */
typedef struct
{
int Keyb;
int Turns;
int Shifts;
} SpatialMatchInfo_t;
/* Shift mapping, characters in pairs: first is shifted, second un-shifted. */
static const uint8_t UK_Shift[] = "!1\"2$4%5&7(9)0*8:;<,>.?/@'AaBbCcDdEeFfGgHhIiJjKkLlMmNnOoPpQqRrSsTtUuVvWwXxYyZz^6_-{[|\\}]~#4£3¬`";
static const uint8_t US_Shift[] = "!1\"'#3$4%5&7(9)0*8:;<,>.?/@2AaBbCcDdEeFfGgHhIiJjKkLlMmNnOoPpQqRrSsTtUuVvWwXxYyZz^6_-{[|\\}]~`";
/* Neighour tables */
static const uint8_t UK_Qwerty[48*7] =
{
/* key, left, up-left, up-right, right, down-right, down-left */
'#', '\'',']', 0, 0, 0, 0, '\'',';', '[', ']', '#', 0, '/',
',', 'm', 'k', 'l', '.', 0, 0, '-', '0', 0, 0, '-', 'p', 'o',
'.', ',', 'l', ';', '/', 0, 0, '/', '.', ';', '\'', 0, 0, 0,
'0', '9', 0, 0, '-', 'p', 'o', '1', '`', 0, 0, '2', 'q', 0,
'2', '1', 0, 0, '3', 'w', 'q', '3', '2', 0, 0, '4', 'e', 'w',
'4', '3', 0, 0, '5', 'r', 'e', '5', '4', 0, 0, '6', 't', 'r',
'6', '5', 0, 0, '7', 'y', 't', '7', '6', 0, 0, '8', 'u', 'y',
'8', '7', 0, 0, '9', 'i', 'u', '9', '8', 0, 0, '0', 'o', 'i',
';', 'l', 'o', 'p','\'', '/', '.', '=', '-', 0, 0, 0, ']', '[',
'[', 'p', '-', '=', ']', '\'',';', '\\', 0, 0, 'a', 'z', 0, 0,
']', '[', '=', 0, 0, '#','\'', '`', 0, 0, 0, '1', 0, 0,
'a', 0, 'q', 'w', 's', 'z','\\', 'b', 'v', 'g', 'h', 'n', 0, 0,
'c', 'x', 'd', 'f', 'v', 0, 0, 'd', 's', 'e', 'r', 'f', 'c', 'x',
'e', 'w', '3', '4', 'r', 'd', 's', 'f', 'd', 'r', 't', 'g', 'v', 'c',
'g', 'f', 't', 'y', 'h', 'b', 'v', 'h', 'g', 'y', 'u', 'j', 'n', 'b',
'i', 'u', '8', '9', 'o', 'k', 'j', 'j', 'h', 'u', 'i', 'k', 'm', 'n',
'k', 'j', 'i', 'o', 'l', ',', 'm', 'l', 'k', 'o', 'p', ';', '.', ',',
'm', 'n', 'j', 'k', ',', 0, 0, 'n', 'b', 'h', 'j', 'm', 0, 0,
'o', 'i', '9', '0', 'p', 'l', 'k', 'p', 'o', '0', '-', '[', ';', 'l',
'q', 0, '1', '2', 'w', 'a', 0, 'r', 'e', '4', '5', 't', 'f', 'd',
's', 'a', 'w', 'e', 'd', 'x', 'z', 't', 'r', '5', '6', 'y', 'g', 'f',
'u', 'y', '7', '8', 'i', 'j', 'h', 'v', 'c', 'f', 'g', 'b', 0, 0,
'w', 'q', '2', '3', 'e', 's', 'a', 'x', 'z', 's', 'd', 'c', 0, 0,
'y', 't', '6', '7', 'u', 'h', 'g', 'z', '\\','a', 's', 'x', 0, 0
};
static const uint8_t US_Qwerty[47*7] =
{
/* key, left, up-left, up-right, right, down-right, down-left */
'\'',';', '[', ']', 0, 0, '/', ',', 'm', 'k', 'l', '.', 0, 0,
'-', '0', 0, 0, '=', '[', 'p', '.', ',', 'l', ';', '/', 0, 0,
'/', '.', ';','\'', 0, 0, 0, '0', '9', 0, 0, '-', 'p', 'o',
'1', '`', 0, 0, '2', 'q', 0, '2', '1', 0, 0, '3', 'w', 'q',
'3', '2', 0, 0, '4', 'e', 'w', '4', '3', 0, 0, '5', 'r', 'e',
'5', '4', 0, 0, '6', 't', 'r', '6', '5', 0, 0, '7', 'y', 't',
'7', '6', 0, 0, '8', 'u', 'y', '8', '7', 0, 0, '9', 'i', 'u',
'9', '8', 0, 0, '0', 'o', 'i', ';', 'l', 'p', '[','\'', '/', '.',
'=', '-', 0, 0, 0, ']', '[', '[', 'p', '-', '=', ']','\'', ';',
'\\',']', 0, 0, 0, 0, 0, ']', '[', '=', 0,'\\', 0,'\'',
'`', 0, 0, 0, '1', 0, 0, 'a', 0, 'q', 'w', 's', 'z', 0,
'b', 'v', 'g', 'h', 'n', 0, 0, 'c', 'x', 'd', 'f', 'v', 0, 0,
'd', 's', 'e', 'r', 'f', 'c', 'x', 'e', 'w', '3', '4', 'r', 'd', 's',
'f', 'd', 'r', 't', 'g', 'v', 'c', 'g', 'f', 't', 'y', 'h', 'b', 'v',
'h', 'g', 'y', 'u', 'j', 'n', 'b', 'i', 'u', '8', '9', 'o', 'k', 'j',
'j', 'h', 'u', 'i', 'k', 'm', 'n', 'k', 'j', 'i', 'o', 'l', ',', 'm',
'l', 'k', 'o', 'p', ';', '.', ',', 'm', 'n', 'j', 'k', ',', 0, 0,
'n', 'b', 'h', 'j', 'm', 0, 0, 'o', 'i', '9', '0', 'p', 'l', 'k',
'p', 'o', '0', '-', '[', ';', 'l', 'q', 0, '1', '2', 'w', 'a', 0,
'r', 'e', '4', '5', 't', 'f', 'd', 's', 'a', 'w', 'e', 'd', 'x', 'z',
't', 'r', '5', '6', 'y', 'g', 'f', 'u', 'y', '7', '8', 'i', 'j', 'h',
'v', 'c', 'f', 'g', 'b', 0, 0, 'w', 'q', '2', '3', 'e', 's', 'a',
'x', 'z', 's', 'd', 'c', 0, 0, 'y', 't', '6', '7', 'u', 'h', 'g',
'z', 0, 'a', 's', 'x', 0, 0,
};
static const uint8_t Dvorak[48*7] =
{
'\'', 0, '1', '2', ',', 'a', 0, ',','\'', '2', '3', '.', 'o', 'a',
'-', 's', '/', '=', 0, 0, 'z', '.', ',', '3', '4', 'p', 'e', 'o',
'/', 'l', '[', ']', '=', '-', 's', '0', '9', 0, 0, '[', 'l', 'r',
'1', '`', 0, 0, '2','\'', 0, '2', '1', 0, 0, '3', ',','\'',
'3', '2', 0, 0, '4', '.', ',', '4', '3', 0, 0, '5', 'p', '.',
'5', '4', 0, 0, '6', 'y', 'p', '6', '5', 0, 0, '7', 'f', 'y',
'7', '6', 0, 0, '8', 'g', 'f', '8', '7', 0, 0, '9', 'c', 'g',
'9', '8', 0, 0, '0', 'r', 'c', ';', 0, 'a', 'o', 'q', 0, 0,
'=', '/', ']', 0,'\\', 0, '-', '[', '0', 0, 0, ']', '/', 'l',
'\\','=', 0, 0, 0, 0, 0, ']', '[', 0, 0, 0, '=', '/',
'`', 0, 0, 0, '1', 0, 0, 'a', 0,'\'', ',', 'o', ';', 0,
'b', 'x', 'd', 'h', 'm', 0, 0, 'c', 'g', '8', '9', 'r', 't', 'h',
'd', 'i', 'f', 'g', 'h', 'b', 'x', 'e', 'o', '.', 'p', 'u', 'j', 'q',
'f', 'y', '6', '7', 'g', 'd', 'i', 'g', 'f', '7', '8', 'c', 'h', 'd',
'h', 'd', 'g', 'c', 't', 'm', 'b', 'i', 'u', 'y', 'f', 'd', 'x', 'k',
'j', 'q', 'e', 'u', 'k', 0, 0, 'k', 'j', 'u', 'i', 'x', 0, 0,
'l', 'r', '0', '[', '/', 's', 'n', 'm', 'b', 'h', 't', 'w', 0, 0,
'n', 't', 'r', 'l', 's', 'v', 'w', 'o', 'a', ',', '.', 'e', 'q', ';',
'p', '.', '4', '5', 'y', 'u', 'e', 'q', ';', 'o', 'e', 'j', 0, 0,
'r', 'c', '9', '0', 'l', 'n', 't', 's', 'n', 'l', '/', '-', 'z', 'v',
't', 'h', 'c', 'r', 'n', 'w', 'm', 'u', 'e', 'p', 'y', 'i', 'k', 'j',
'v', 'w', 'n', 's', 'z', 0, 0, 'w', 'm', 't', 'n', 'v', 0, 0,
'x', 'k', 'i', 'd', 'b', 0, 0, 'y', 'p', '5', '6', 'f', 'i', 'u',
'z', 'v', 's', '-', 0, 0, 0
};
static const uint8_t PC_Keypad[15*9] =
{
/*Key, left, up-left, up, up-right, right, down-right, down, down-left */
'*', '/', 0, 0, 0, '-', '+', '9', '8',
'+', '9', '*', '-', 0, 0, 0, 0, '6',
'-', '*', 0, 0, 0, 0, 0, '+', '9',
'.', '0', '2', '3', 0, 0, 0, 0, 0,
'/', 0, 0, 0, 0, '*', '9', '8', '7',
'0', 0, '1', '2', '3', '.', 0, 0, 0,
'1', 0, 0, '4', '5', '2', '0', 0, 0,
'2', '1', '4', '5', '6', '3', '.', '0', 0,
'3', '2', '5', '6', 0, 0, 0, '.', '0',
'4', 0, 0, '7', '8', '5', '2', '1', 0,
'5', '4', '7', '8', '9', '6', '3', '2', '1',
'6', '5', '8', '9', '+', 0, 0, '3', '2',
'7', 0, 0, 0, '/', '8', '5', '4', 0,
'8', '7', 0, '/', '*', '9', '6', '5', '4',
'9', '8', '/', '*', '-', '+', 0, '6', '5'
};
static const uint8_t MacKeypad[16*9] =
{
'*', '/', 0, 0, 0, 0, 0, '-', '9',
'+', '6', '9', '-', 0, 0, 0, 0, '3',
'-', '9', '/', '*', 0, 0, 0, '+', '6',
'.', '0', '2', '3', 0, 0, 0, 0, 0,
'/', '=', 0, 0, 0, '*', '-', '9', '8',
'0', 0, '1', '2', '3', '.', 0, 0, 0,
'1', 0, 0, '4', '5', '2', '0', 0, 0,
'2', '1', '4', '5', '6', '3', '.', '0', 0,
'3', '2', '5', '6', '+', 0, 0, '.', '0',
'4', 0, 0, '7', '8', '5', '2', '1', 0,
'5', '4', '7', '8', '9', '6', '3', '2', '1',
'6', '5', '8', '9', '-', '+', 0, '3', '2',
'7', 0, 0, 0, '=', '8', '5', '4', 0,
'8', '7', 0, '=', '/', '9', '6', '5', '4',
'9', '8', '=', '/', '*', '-', '+', '6', '5',
'=', 0, 0, 0, 0, '/', '9', '8', '7'
};
static const Keyboard_t Keyboards[] =
{
{ US_Qwerty, US_Shift, sizeof US_Qwerty / 7, 7, sizeof US_Shift / 2, 66 },
{ Dvorak, US_Shift, sizeof Dvorak / 7, 7, sizeof US_Shift / 2, 66 },
{ UK_Qwerty, UK_Shift, sizeof UK_Qwerty / 7, 7, sizeof UK_Shift / 2, 66 },
{ MacKeypad, 0, sizeof MacKeypad / 9, 9, 0, 44 },
{ PC_Keypad, 0, sizeof PC_Keypad / 9, 9, 0, 44 }
};
/**********************************************************************************
* Match password for the given keyboard layout
*/
static int DoSptlMatch(const uint8_t *Passwd, int MaxLen, const Keyboard_t *Keyb, SpatialMatchInfo_t *Extra)
{
int i;
int ShiftCount = 0;
int Turns = 0;
int Dir = -1;
int Len = 0;
uint8_t PrevChar = 0;
for( ; *Passwd && (Len < MaxLen); ++Passwd, ++Len)
{
const uint8_t *Key;
int s = 0;
uint8_t CurChar = *Passwd;
/* Try to unshift the character */
if (Keyb->Shifts)
{
Key = CharBinSearch(CurChar, Keyb->Shifts, Keyb->NumShift, 2);
if (Key)
{
/* Shifted char */
CurChar = Key[1];
s = 1;
}
}
if (PrevChar)
{
/* See if the pattern can be extended */
i = 0;
Key = CharBinSearch(PrevChar, Keyb->Keys, Keyb->NumKeys, Keyb->NumNear);
if (Key)
{
for(i = Keyb->NumNear - 1; i > 0; --i)
{
if (Key[i] == CurChar)
break;
}
}
if (i)
{
Turns += (i != Dir);
Dir = i;
ShiftCount += s;
}
else
{
break;
}
}
PrevChar = CurChar;
}
if (Len >= MIN_SPATIAL_LEN)
{
Extra->Turns = Turns;
Extra->Shifts = ShiftCount;
return Len;
}
return 0;
}
/**********************************************************************************
* Try to match spatial patterns on the keyboard
* Parameters:
* Result Pointer head of linked list used to store results
* Passwd The start of the password
* Start Where in the password to start attempting to match
* MaxLen Maximum number characters to consider
*/
static void SpatialMatch(ZxcMatch_t **Result, const uint8_t *Passwd, int Start, int MaxLen)
{
unsigned int Indx;
int Len, CurLen;
SpatialMatchInfo_t Extra;
const Keyboard_t *k;
Passwd += Start;
for(CurLen = MaxLen; CurLen >= MIN_SPATIAL_LEN;CurLen = Len - 1)
{
Len = 0;
memset(&Extra, 0, sizeof Extra);
for(k = Keyboards, Indx = 0; Indx < (sizeof Keyboards / sizeof Keyboards[0]); ++Indx, ++k)
{
Len = DoSptlMatch(Passwd, CurLen, k, &Extra);
if (Len > 0)
{
/* Got a sequence of required length so add to result list */
int i, j, s;
double Degree, Entropy;
ZxcMatch_t *p;
Degree = (k->NumNear-1) - (double)k->NumBlank / (double)k->NumKeys;
s = k->NumKeys;
if (k->Shifts)
s *= 2;
/* Estimate the number of possible patterns with length ranging 2 to match length and */
/* with turns ranging from 0 to match turns */
Entropy = 0.0;
for(i = 2; i <= Len; ++i)
{
int PossTurns = Extra.Turns;
if (PossTurns >= i)
PossTurns = i-1;
for(j = 1; j <= PossTurns; ++j)
Entropy += nCk(i-1, j-1) * pow(Degree, j) * s;
}
if (Entropy > 0.0)
Entropy = log(Entropy);
if (Extra.Shifts)
{
/* Add extra entropy for shifted keys. (% instead of 5, A instead of a etc.) */
/* Math is similar to extra entropy from uppercase letters in dictionary matches. */
int Shift = Extra.Shifts;
int Unshift = Len - Shift;
Degree = 0.0;
j = Shift;
if (j > Unshift)
j = Unshift;
for(i = 0; i <= j; ++i)
{
Degree += nCk(Len, i);
}
if (Degree > 0.0)
Entropy += log(Degree);
}
p = AllocMatch();
p->Type = SPATIAL_MATCH;
p->Begin = Start;
p->Entrpy = Entropy;
p->Length = Len;
AddResult(Result, p);
break;
}
}
}
}
/*################################################################################*
*################################################################################*
* Begin date matching code
*################################################################################*
*################################################################################*/
#define MIN_YEAR 1901
#define MAX_YEAR 2019
/* The possible date formats ordered by length (d for day, m for month, */
/* y for year, ? for separator) */
static const char *Formats[] =
{
"yyyy",
"d?m?yy",
"ddmmyy",
"dmyyyy",
"dd?m?yy",
"d?mm?yy",
"ddmyyyy",
"dmmyyyy",
"yyyymmd",
"yyyymdd",
"d?m?yyyy",
"dd?mm?yy",
"ddmmyyyy",
"yyyy?m?d",
"yyyymmdd",
"dd?m?yyyy",
"d?mm?yyyy",
"yyyy?mm?d",
"yyyy?m?dd",
"dd?mm?yyyy",
"yyyy?mm?dd",
0
};
/* Possible separator characters that could be used */
static const char DateSeperators[] = "/\\-_. ";
/**********************************************************************************
* Try to match the password with the formats above.
*/
static void DateMatch(ZxcMatch_t **Result, const uint8_t *Passwd, int Start, int MaxLen)
{
int CurFmt;
int YrLen = 0;
int PrevLen = 0;
uint8_t Sep = 0;
Passwd += Start;
for(CurFmt = 0; Formats[CurFmt]; ++CurFmt)
{
int Len = 0;
int Year = 0;
int Mon = 0;
int Day = 0;
int Fail = 0;
const uint8_t *p = Passwd;
const char *Fmt;
YrLen = 0;
Sep = 0;
/* Scan along the format, trying to match the password */
for(Fmt = Formats[CurFmt]; *Fmt && !Fail; ++Fmt)
{
if (*Fmt == '?')
{
if (!Sep && strchr(DateSeperators, *p))
Sep = *p;
Fail = (*p != Sep);
}
else if (isdigit(*p))
{
if (*Fmt == 'd')
{
Day = 10 * Day + *p - '0';
}
else if (*Fmt == 'm')
{
Mon = 10 * Mon + *p - '0';
}
else
{
Year = 10 * Year + *p - '0';
++YrLen;
}
}
else
{
Fail = 1;
}
++p;
++Len;
if (Len >= MaxLen)
break;
}
if (Len < 4)
Fail = 1;
if (!Fail)
{
/* Character matching is OK, now check to see if valid date */
if (((YrLen > 3) || (Len <= 4)) && ((Year < MIN_YEAR) || (Year > MAX_YEAR)))
Fail = 1;
else if (Len > 4)
{
if ((Mon > 12) && (Day < 13))
{
/* Swap day,month to try to make both in range */
int i = Mon;
Mon = Day;
Day = i;
}
/* Check for valid day, month. Currently assumes all months have 31 days. */
if ((Mon < 1) || (Mon > 12))
Fail = 1;
else if ((Day < 1) || (Day > 31))
Fail = 1;
}
}
if (!Fail && (Len > PrevLen))
{
/* String matched the date, store result */
double e;
ZxcMatch_t *p = AllocMatch();
if (Len <= 4)
e = log(MAX_YEAR - MIN_YEAR + 1.0);
else if (YrLen > 3)
e = log(31 * 12 * (MAX_YEAR - MIN_YEAR + 1.0));
else
e = log(31 * 12 * 100.0);
if (Sep)
e += log(4.0); /* Extra 2 bits for separator */
p->Entrpy = e;
p->Type = DATE_MATCH;
p->Length = Len;
p->Begin = Start;
AddResult(Result, p);
PrevLen = Len;
}
}
}
/*################################################################################*
*################################################################################*
* Begin repeated character matching code
*################################################################################*
*################################################################################*/
#define MIN_REPEAT_LEN 3
/**********************************************************************************
* Try to match password part as a set of repeated characters.
* Parameters:
* Result Pointer head of linked list used to store results
* Passwd The start of the password
* Start Where in the password to start attempting to match
* MaxLen Maximum number characters to consider
*/
static void RepeatMatch(ZxcMatch_t **Result, const uint8_t *Passwd, int Start, int MaxLen)
{
int Len, i;
uint8_t c;
Passwd += Start;
/* Remember first char and the count its occurances */
c = *Passwd;
for(Len = 1; (Len < MaxLen) && (c == Passwd[Len]); ++Len)
{ }
if (Len >= MIN_REPEAT_LEN)
{
/* Enough repeated char, so create results from number found down to min acceptable repeats */
double Card = Cardinality(&c, 1);
for(i = Len; i >= MIN_REPEAT_LEN; --i)
{
ZxcMatch_t *p = AllocMatch();
p->Type = REPEATS_MATCH;
p->Begin = Start;
p->Length = i;
p->Entrpy = log(Card * i);
AddResult(Result, p);
}
}
}
/**********************************************************************************
**********************************************************************************
* Begin character sequence matching code
**********************************************************************************
*********************************************************************************/
#define MIN_SEQUENCE_LEN 3
/**********************************************************************************
* Try to match password part as a set of incrementing or decrementing characters.
* Parameters:
* Result Pointer head of linked list used to store results
* Passwd The start of the password
* Start Where in the password to start attempting to match
* MaxLen Maximum number characters to consider
*/
static void SequenceMatch(ZxcMatch_t **Result, const uint8_t *Passwd, int Start, int MaxLen)
{
int Len=0;
int SetLow, SetHigh, Dir;
uint8_t First, Next;
Passwd += Start;
First = Passwd[0];
Dir = Passwd[1] - First;
Len = 0;
/* Decide on min and max character code for sequence */
if (islower(*Passwd))
{
SetLow = 'a';
SetHigh = 'z';
}
else if (isupper(*Passwd))
{
SetLow = 'A';
SetHigh = 'Z';
}
else if (isdigit(*Passwd))
{
SetLow = '0';
SetHigh = '9';
if ((First == '0') && (Dir == 9))
{
/* Special case for decrementing sequence of digits, allow starting with 098 */
Dir = -1;
++Len;
++Passwd;
}
}
else
return;
if ((Dir == 1) || (Dir == -1))
{
++Len;
while(1)
{
if ((Passwd[0] == '9') && (Passwd[1] == '0') && (Dir > 0))
{
++Len;
++Passwd;
break;
}
Next = Passwd[0] + Dir;
if ((Next > SetHigh) || (Next < SetLow) || (Passwd[1] != Next))
break;
++Len;
++Passwd;
if (Len >= MaxLen)
break;
}
}
if (Len >= MIN_SEQUENCE_LEN)
{
/* Enough repeated char, so create results from number found down to min acceptable length */
int i;
double e;
if ((First == 'a') || (First == '1'))
e = log(2.0);
else if (isdigit(First))
e = log(10.0);
else if (isupper(First))
e = log(26*2.0);
else
e = log(26.0);
if (Dir < 0)
e += log(2.0);
for(i = Len; i >= MIN_SEQUENCE_LEN; --i)
{
ZxcMatch_t *p = AllocMatch();
/* Add new result to head of list as it has lower entropy */
p->Type = SEQUENCE_MATCH;
p->Begin = Start;
p->Length = i;
p->Entrpy = e + log((double)i);
AddResult(Result, p);
}
}
}
/**********************************************************************************
**********************************************************************************
* Begin top level zxcvbn code
**********************************************************************************
*********************************************************************************/
/**********************************************************************************
* Matching a password is treated as a problem of finding the minimum distance
* between two vertexes in a graph. This is solved using Dijkstra's algorithm.
*
* There are a series of nodes (or vertexes in graph terminology) which correspond
* to points between each character of the password. Also there is a start node
* before the first character and an end node after the last character.
*
* The paths between the nodes (or edges in graph terminology) correspond to the
* matched parts of the password (e.g. dictionary word, repeated characters etc).
* The distance of the path is equal to the entropy of the matched part. A default
* single character bruteforce match path is also added for all nodes except the
* end node.
*
* Dijkstra's algorithm finds the combination of these part matches (or paths)
* which gives the lowest entropy (or smallest distance) from begining to end
* of the password.
*/
/* Struct to hold the data of a node (imaginary point between password characters) */
typedef struct
{
ZxcMatch_t *Paths; /* Partial matches that lead to a following node */
double Dist; /* Distance (or entropy) from start of password to this node */
ZxcMatch_t *From; /* Which path was used to get to this node with lowest distance/entropy */
int Visit; /* Non zero when node has been visited during Dijkstra evaluation */
} Node_t;
/**********************************************************************************
* Main function of the zxcvbn password entropy estimation
*/
double ZxcvbnMatch(const char *Pwd, const char *UserDict[], ZxcMatch_t **Info)
{
int i;
ZxcMatch_t *Zp;
Node_t *Np;
double e;
int Len = strlen(Pwd);
const uint8_t *Passwd = (const uint8_t *)Pwd;
/* Create the paths */
Node_t *Nodes = MallocFn(Node_t, Len+1);
memset(Nodes, 0, (Len+1) * sizeof *Nodes);
i = Cardinality(Passwd, Len);
e = log((double)i);
/* Do matching for all parts of the password */
for(i = 0; i < Len; ++i)
{
int MaxLen = Len - i;
/* Add all the 'paths' between groups of chars in the password, for current starting char */
UserMatch(&(Nodes[i].Paths), UserDict, Passwd, i, MaxLen);
DictionaryMatch(&(Nodes[i].Paths), Passwd, i, MaxLen);
DateMatch(&(Nodes[i].Paths), Passwd, i, MaxLen);
SpatialMatch(&(Nodes[i].Paths), Passwd, i, MaxLen);
SequenceMatch(&(Nodes[i].Paths), Passwd, i, MaxLen);
RepeatMatch(&(Nodes[i].Paths), Passwd, i, MaxLen);
/* Add a default one character bruteforce path */
Zp = AllocMatch();
Zp->Type = BRUTE_MATCH;
Zp->Begin = i;
Zp->Length = 1;
Zp->Entrpy = e;
AddResult(&(Nodes[i].Paths), Zp);
/* Initially set distance to nearly infinite */
Nodes[i].Dist = DBL_MAX;
}
/* End node has infinite distance/entropy, start node has 0 distance */
Nodes[i].Dist = DBL_MAX;
Nodes[0].Dist = 0.0;
/* Reduce the paths using Dijkstra's algorithm */
for(i = 0; i < Len; ++i)
{
int j;
double MinDist = DBL_MAX;
int MinIdx = 0;
/* Find the unvisited node with minimum distance or entropy */
for(Np = Nodes, j = 0; j < Len; ++j, ++Np)
{
if (!Np->Visit && (Np->Dist < MinDist))
{
MinIdx = j;
MinDist = Np->Dist;
}
}
/* Mark the minimum distance node as visited */
Np = Nodes + MinIdx;
Np->Visit = 1;
e = Np->Dist;
/* Update all unvisited neighbouring nodes with their new distance. A node is a */
/* neighbour if there is a path/match from current node Np to it. The neighbour */
/* distance is the current node distance plus the path distance/entropy. Only */
/* update if the new distance is smaller. */
for(Zp = Np->Paths; Zp; Zp = Zp->Next)
{
Node_t *Ep = Np + Zp->Length;
double d = e + Zp->Entrpy;
if (!Ep->Visit && (d < Ep->Dist))
{
/* Update as lower dist, also remember the 'from' node */
Ep->Dist = d;
Ep->From = Zp;
}
}
/* If we got to the end node stop early */
/*if (Nodes[Len].Dist < DBL_MAX/2.0) */
/* break; */
}
/* Make e hold entropy result and adjust to log base 2 */
e = Nodes[Len].Dist / log(2.0);
if (Info)
{
/* Construct info on password parts */
*Info = 0;
for(Zp = Nodes[Len].From; Zp; )
{
ZxcMatch_t *Xp;
i = Zp->Begin;
/* Remove all but required path */
Xp = Nodes[i].Paths;
Nodes[i].Paths = 0;
while(Xp)
{
ZxcMatch_t *p = Xp->Next;
if (Xp == Zp)
{
/* Adjust the entropy to log to base 2 */
Xp->Entrpy /= log(2.0);
if ((*Info) && (Xp->Type == BRUTE_MATCH) && ((*Info)->Type == BRUTE_MATCH))
{
/* Previous part and current are bruteforce, merge then into single entry */
(*Info)->Begin = Xp->Begin;
(*Info)->Length += Xp->Length;
(*Info)->Entrpy += Xp->Entrpy;
FreeFn(Xp);
}
else
{
/* Put previous part at head of info list */
Xp->Next = *Info;
*Info = Xp;
}
}
else
{
/* Not going on info list, so free it */
FreeFn(Xp);
}
Xp = p;
}
Zp = Nodes[i].From;
}
}
/* Free all paths. Any being returned to caller have already been freed */
for(i = 0; i <= Len; ++i)
{
Zp = Nodes[i].Paths;
while(Zp)
{
ZxcMatch_t *p = Zp->Next;
FreeFn(Zp);
Zp = p;
}
}
FreeFn(Nodes);
return e;
}
/**********************************************************************************
* Free the path info returned by ZxcvbnMatch().
*/
void ZxcvbnFreeInfo(ZxcMatch_t *Info)
{
ZxcMatch_t *p;
while(Info)
{
p = Info->Next;
FreeFn(Info);
Info = p;
}
}