public override double entropy(PasswordSequenceConfiguration config)
{
double entropyVal = 0;
if (Length > 0)
{
uint len = Length;
uint charlist_len = 0;
if (Characters != null)
{
charlist_len = (uint)Characters.Count;
}
if (Characters == null || !Characters.Override)
{
charlist_len += (uint)config.DefaultCharacters.Count;
}
if (!AllowDuplicate)
{
len = (len <= charlist_len ? len : charlist_len);
}
double cur_len_entropy = 0.0;
uint cur_len = len;
while (cur_len > 0 && charlist_len > 0)
{
cur_len_entropy += Math.Log(charlist_len, 2);
if (LengthStrength < StrengthEnum.Full)
{
if (cur_len > 1)
{
entropyVal += (1 - (double)LengthStrength / 100) * cur_len_entropy / len;
}
}
if (!AllowDuplicate)
{
charlist_len -= 1;
}
cur_len -= 1;
}
entropyVal += ((double)LengthStrength / 100) * cur_len_entropy;
}
return(entropyVal);
}
public override double entropy(PasswordSequenceConfiguration config)
{
double entropyVal = 0;
List <string> wordList = new List <string>();
if (Words != null)
{
wordList.AddRange(Words);
}
if (Words == null || !Words.Override)
{
wordList.AddRange(config.DefaultWords);
}
List <BaseSubstitution> applicableSubstitution = new List <BaseSubstitution>();
if (Substitution > PercentEnum.Never)
{
if (Substitutions != null)
{
applicableSubstitution.AddRange(Substitutions);
}
if (Substitutions == null || !Substitutions.Override)
{
applicableSubstitution.AddRange(config.DefaultSubstitutions);
}
}
if (wordList.Count > 0)
{
entropyVal += Math.Log(wordList.Count, 2);
}
/* collect stats about the word list and how substitions apply */
double avg_word_len = 0;
int subst_hit_count = 0;
foreach (string word in wordList)
{
avg_word_len += word.Length;
foreach (BaseSubstitution substitution in applicableSubstitution)
{
subst_hit_count += new SubstitutionVisitor(null)
.CountSubstitution(substitution, word);
}
}
avg_word_len /= wordList.Count;
double avg_subst_hits = (double)subst_hit_count / wordList.Count;
/* apply information added by capitalization */
double cap_chance = 0;
if (Capitalize != CapitalizeEnum.Proper)
{
cap_chance = (double)Capitalize / 100.0;
}
if (cap_chance > 0.0 && cap_chance < 1.0)
{
entropyVal += avg_word_len * cap_chance * Math.Log(1 / cap_chance, 2);
entropyVal += avg_word_len * (1 - cap_chance) * Math.Log(1 / (1 - cap_chance), 2);
}
/* apply average information added by substitutions */
double subst_chance = (double)Substitution / 100.0;
subst_chance = (double)Substitution / 100.0;
if (subst_chance > 0.0 && subst_chance < 1.0)
{
entropyVal += avg_subst_hits * subst_chance * Math.Log(1 / subst_chance, 2);
entropyVal += avg_subst_hits * (1 - subst_chance) * Math.Log(1 / (1 - subst_chance), 2);
}
/* Chance of not including the word actually decreases entropy
* because there is a chance the attacker needs to try fewer words.
*/
entropyVal = entropyVal * (double)Probability / 100;
return(entropyVal);
}
public abstract double entropy(PasswordSequenceConfiguration config);
