C语言实现密码强度检测

int passwdmeter(char *passwd)
{
 int i = 0;
 //1.密码长度
 int passwdlen;
 passwdlen = strlen(passwd);
 
 //2~5.大小写字母个数,数字个数,符号个数
 int UppercaseLetters = 0;
 int LowercaseLetters = 0;
 int Numbers = 0,Symbols = 0;
 for(i = 0;i < passwdlen; i++)
 {
 if (passwd[i]>='a' && passwd[i] <= 'z')
  LowercaseLetters++;
 else if (passwd[i]>='A' && passwd[i] <= 'Z')
  UppercaseLetters++;
 else if(passwd[i]>='0' && passwd[i] <= '9')
  Numbers++;
 else
  Symbols++;
 }
 
 //6.位于中间的数字或符号
 int MiddleNumbersorSymbols = Numbers+Symbols;
 
 if (passwd[0]>='a' && passwd[0] <= 'z') ;
 else if (passwd[0]>='A' && passwd[0] <= 'Z') ;
 else if(passwd[0]>='0' && passwd[0] <= '9')
 MiddleNumbersorSymbols--;
 else
 MiddleNumbersorSymbols--;
 
 if (passwd[passwdlen - 1]>='a' && passwd[passwdlen - 1] <= 'z') ;
 else if (passwd[passwdlen - 1]>='A' && passwd[passwdlen - 1] <= 'Z') ;
 else if(passwd[passwdlen - 1]>='0' && passwd[passwdlen - 1] <= '9')
 MiddleNumbersorSymbols--;
 else
 MiddleNumbersorSymbols--;
 
 //7.最低条件得分
 int Requirements = 0;
 if(UppercaseLetters > 0)Requirements++;
 if(LowercaseLetters > 0)Requirements++;
 if(Numbers > 0)Requirements++;
 if(Symbols > 0)Requirements++;
 if(passwdlen > 8)Requirements++;
 
 //总加得分
 int Bonus = passwdlen*4 + Symbols*6 + MiddleNumbersorSymbols*2;
 if (UppercaseLetters)Bonus+= (passwdlen - UppercaseLetters)*2;
 if (LowercaseLetters)Bonus+= (passwdlen - LowercaseLetters)*2;
 if (Requirements > 3)Bonus+= Requirements*2;
 if (Numbers != passwdlen)Bonus+= Numbers*4;
 
 //1.只有字母
 int LettersOnly = 0;
 if (UppercaseLetters + LowercaseLetters == passwdlen)
 LettersOnly = passwdlen;
 
 //2.只有数字
 int NumbersOnly = 0;
 if (Numbers == passwdlen)
 NumbersOnly = passwdlen;
 
 //3.重复字符数（大小写敏感）
 int RepeatCharacters = 0;
 int repChar = 0;
 for(i = 0; i < passwdlen; i++) {
 int exists = 0;
 int j = 0;
 for (j = 0; j < passwdlen; j++) {
   if (passwd[i] == passwd[j] && i != j) {
     exists = 1;
     RepeatCharacters += abs(passwdlen/(j-i));
   }
 }
 if (exists) {
   repChar++;
   int unqChar = passwdlen - repChar;
   RepeatCharacters = (unqChar) ? ceil(RepeatCharacters/(double)unqChar) : ceil(RepeatCharacters);
 }
 }
 
 //4~6.连续大小写字母，数字
 int ConsecutiveUppercaseLetters = 0;
 int ConsecutiveLowercaseLetters = 0;
 int ConsecutiveNumbers  = 0;
 
 int flag = 0;//1-小写，2-大写，3-数字
 int count = 0;
 for(i = 0 ;i < passwdlen;i++)
 {
 if(i == 0){
  if (passwd[i]>='a' && passwd[i] <= 'z'){flag = 1;count = 1;}
  else if (passwd[i]>='A' && passwd[i] <= 'Z'){flag = 2;count = 1;}
  else if(passwd[i]>='0' && passwd[i] <= '9'){flag = 3;count = 1;}
 }else
 {
  int tmpflag = 0;
  if (passwd[i]>='a' && passwd[i] <= 'z')
  {
  tmpflag = 1;
  }
  else if (passwd[i]>='A' && passwd[i] <= 'Z')
  {
  tmpflag = 2;
  }
  else if(passwd[i]>='0' && passwd[i] <= '9')
  {
  tmpflag = 3;
  }else
  {
  tmpflag = 0;
  }
 
  if(tmpflag == flag)
  count++;
  else
  {
  if(count >= 2)
  {
   switch(flag)
   {
   case 1:
    ConsecutiveLowercaseLetters += count-1;break;
   case 2:
    ConsecutiveUppercaseLetters += count-1;break;
   case 3:
    ConsecutiveNumbers += count-1;break;
   default:
   break;
   }
  }
  flag = tmpflag;
  count = 1;
  }
 }
 }
 
 if(count >= 2)
 {
 switch(flag)
 {
  case 1:
  ConsecutiveLowercaseLetters += count-1;break;
  case 2:
  ConsecutiveUppercaseLetters += count-1;break;
  case 3:
  ConsecutiveNumbers += count-1;break;
  default:
  break;
 }
 }
 
 //7~9 正序或者逆序的字母数字及符号
 int SequentialLetters = 0;
 
 int Sequenflag = 0;//1-正序，2-反序
 int Sequencount = 1; 
 for(i = 1 ;i < passwdlen;i++)
 {
 int value = passwd[i];
 if(passwd[i]>='a' && passwd[i] <= 'z' && passwd[i-1]>='A' && passwd[i-1] <= 'Z')
  value = passwd[i] - 32;
 else if(passwd[i-1]>='a' && passwd[i-1] <= 'z' && passwd[i]>='A' && passwd[i] <= 'Z')
  value = passwd[i] + 32;
 
 int tmpflag = 0;
 if (value - 1 == passwd[i-1])
 {
  tmpflag = 1;
 }else if (value + 1 == passwd[i-1])
  tmpflag = 2;
 else 
  tmpflag = 0;
 
 if(Sequenflag == 0 && tmpflag != 0)
 {
  Sequencount = 1;
  Sequenflag = tmpflag;
 }
 
 if (tmpflag == Sequenflag)
 {
  Sequencount++;
 }else
 {
  if(Sequencount >= 3 && Sequenflag != 0)
  SequentialLetters += Sequencount-2;
 
  Sequencount = 1;
  Sequenflag = tmpflag;
 }
 }
 
 if(Sequencount >= 3 && Sequenflag != 0)
 SequentialLetters += Sequencount-2;
 
 //减分项计算
 int Bonus2 = LettersOnly + NumbersOnly + RepeatCharacters + (ConsecutiveUppercaseLetters+ConsecutiveLowercaseLetters+ConsecutiveNumbers)*2 + SequentialLetters*3;
 
 int sum = 0;
 if (Bonus - Bonus2 < 0)
 return 0;
 
 return (Bonus - Bonus2) > 100?100:(Bonus - Bonus2);
}