Automattic /
jetpack
| @@ 530-549 (lines=20) @@ | ||
| 527 | * |
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| 528 | * @param String $password the password. |
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| 529 | */ |
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| 530 | protected function calculate_entropy_bits( $password ) { |
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| 531 | $bits = 0; |
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| 532 | $charset_score = log( $this->get_charset_size( $password ) ) / log( 2 ); |
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| 533 | ||
| 534 | $aidx = $this->get_char_index( $password[0] ); |
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| 535 | $length = strlen( $password ); |
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| 536 | ||
| 537 | for ( $b = 1; $b < $length; $b++ ) { |
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| 538 | $bidx = $this->get_char_index( $password[ $b ] ); |
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| 539 | ||
| 540 | // 27 = number of chars in the index (a-z,' '). |
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| 541 | $c = 1.0 - $this->frequency_table[ $aidx * 27 + $bidx ]; |
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| 542 | $bits += $charset_score * $c * $c; |
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| 543 | ||
| 544 | // Move on to next pair. |
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| 545 | $aidx = $bidx; |
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| 546 | } |
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| 547 | ||
| 548 | return $bits; |
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| 549 | } |
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| 550 | ||
| 551 | /** |
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| 552 | * A frequency table of character pairs, starting with ' ' then ' a', ' b' [...] , 'a ', 'aa' etc. |
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| @@ 554-573 (lines=20) @@ | ||
| 551 | * |
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| 552 | * @param String $password the password. |
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| 553 | */ |
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| 554 | protected function calculate_entropy_bits( $password ) { |
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| 555 | $bits = 0; |
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| 556 | $charset_score = log( $this->get_charset_size( $password ) ) / log( 2 ); |
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| 557 | ||
| 558 | $aidx = $this->get_char_index( $password[0] ); |
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| 559 | $length = strlen( $password ); |
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| 560 | ||
| 561 | for ( $b = 1; $b < $length; $b++ ) { |
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| 562 | $bidx = $this->get_char_index( $password[ $b ] ); |
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| 563 | ||
| 564 | // 27 = number of chars in the index (a-z,' '). |
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| 565 | $c = 1.0 - $this->frequency_table[ $aidx * 27 + $bidx ]; |
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| 566 | $bits += $charset_score * $c * $c; |
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| 567 | ||
| 568 | // Move on to next pair. |
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| 569 | $aidx = $bidx; |
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| 570 | } |
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| 571 | ||
| 572 | return $bits; |
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| 573 | } |
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| 574 | ||
| 575 | /** |
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| 576 | * A frequency table of character pairs, starting with ' ' then ' a', ' b' [...] , 'a ', 'aa' etc. |
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