v0.0.374 ppwgen

cryptext/pronouncablePassword.go

@@ -0,0 +1,263 @@
+package cryptext
+
+import (
+	"crypto/rand"
+	"io"
+	"math/big"
+	mathrand "math/rand"
+	"strings"
+)
+
+const (
+	ppStartChar            = "BCDFGHJKLMNPQRSTVWXZ"
+	ppEndChar              = "ABDEFIKMNORSTUXYZ"
+	ppVowel                = "AEIOUY"
+	ppConsonant            = "BCDFGHJKLMNPQRSTVWXZ"
+	ppSegmentLenMin        = 3
+	ppSegmentLenMax        = 7
+	ppMaxRepeatedVowel     = 2
+	ppMaxRepeatedConsonant = 2
+)
+
+var ppContinuation = map[uint8]string{
+	'A': "BCDFGHJKLMNPRSTVWXYZ",
+	'B': "ADFIKLMNORSTUY",
+	'C': "AEIKOUY",
+	'D': "AEILORSUYZ",
+	'E': "BCDFGHJKLMNPRSTVWXYZ",
+	'F': "ADEGIKLOPRTUY",
+	'G': "ABDEFHILMNORSTUY",
+	'H': "AEIOUY",
+	'I': "BCDFGHJKLMNPRSTVWXZ",
+	'J': "AEIOUY",
+	'K': "ADEFHILMNORSTUY",
+	'L': "ADEFGIJKMNOPSTUVWYZ",
+	'M': "ABEFIKOPSTUY",
+	'N': "ABEFIKOPSTUY",
+	'O': "BCDFGHJKLMNPRSTVWXYZ",
+	'P': "AEFIJLORSTUY",
+	'Q': "AEIOUY",
+	'R': "ADEFGHIJKLMNOPSTUVYZ",
+	'S': "ACDEIKLOPTUYZ",
+	'T': "AEHIJOPRSUWY",
+	'U': "BCDFGHJKLMNPRSTVWXZ",
+	'V': "AEIOUY",
+	'W': "AEIOUY",
+	'X': "AEIOUY",
+	'Y': "ABCDFGHKLMNPRSTVXZ",
+	'Z': "AEILOTUY",
+}
+
+var ppLog2Map = map[int]float64{
+	1:  0.00000000,
+	2:  1.00000000,
+	3:  1.58496250,
+	4:  2.00000000,
+	5:  2.32192809,
+	6:  2.58496250,
+	7:  2.80735492,
+	8:  3.00000000,
+	9:  3.16992500,
+	10: 3.32192809,
+	11: 3.45943162,
+	12: 3.58496250,
+	13: 3.70043972,
+	14: 3.80735492,
+	15: 3.90689060,
+	16: 4.00000000,
+	17: 4.08746284,
+	18: 4.16992500,
+	19: 4.24792751,
+	20: 4.32192809,
+	21: 4.39231742,
+	22: 4.45943162,
+	23: 4.52356196,
+	24: 4.58496250,
+	25: 4.64385619,
+	26: 4.70043972,
+	27: 4.75488750,
+	28: 4.80735492,
+	29: 4.85798100,
+	30: 4.90689060,
+	31: 4.95419631,
+	32: 5.00000000,
+}
+
+var (
+	ppVowelMap     = ppMakeSet(ppVowel)
+	ppConsonantMap = ppMakeSet(ppConsonant)
+	ppEndCharMap   = ppMakeSet(ppEndChar)
+)
+
+func ppMakeSet(v string) map[uint8]bool {
+	mp := make(map[uint8]bool, len(v))
+	for _, chr := range v {
+		mp[uint8(chr)] = true
+	}
+	return mp
+}
+
+func ppRandInt(rng io.Reader, max int) int {
+	v, err := rand.Int(rng, big.NewInt(int64(max)))
+	if err != nil {
+		panic(err)
+	}
+	return int(v.Int64())
+}
+
+func ppRand(rng io.Reader, chars string, entropy *float64) uint8 {
+	chr := chars[ppRandInt(rng, len(chars))]
+
+	*entropy = *entropy + ppLog2Map[len(chars)]
+
+	return chr
+}
+
+func ppCharType(chr uint8) (bool, bool) {
+	_, ok1 := ppVowelMap[chr]
+	_, ok2 := ppConsonantMap[chr]
+
+	return ok1, ok2
+}
+
+func ppCharsetRemove(cs string, set map[uint8]bool, allowEmpty bool) string {
+	result := ""
+	for _, chr := range cs {
+		if _, ok := set[uint8(chr)]; !ok {
+			result += string(chr)
+		}
+	}
+	if result == "" && !allowEmpty {
+		return cs
+	}
+	return result
+}
+
+func ppCharsetFilter(cs string, set map[uint8]bool, allowEmpty bool) string {
+	result := ""
+	for _, chr := range cs {
+		if _, ok := set[uint8(chr)]; ok {
+			result += string(chr)
+		}
+	}
+	if result == "" && !allowEmpty {
+		return cs
+	}
+	return result
+}
+
+func PronouncablePasswordExt(rng io.Reader, pwlen int) (string, float64) {
+
+	// kinda pseudo markov-chain - with a few extra rules and no weights...
+
+	if pwlen <= 0 {
+		return "", 0
+	}
+
+	vowelCount := 0
+	consoCount := 0
+	entropy := float64(0)
+
+	startChar := ppRand(rng, ppStartChar, &entropy)
+
+	result := string(startChar)
+	currentChar := startChar
+
+	isVowel, isConsonant := ppCharType(currentChar)
+	if isVowel {
+		vowelCount = 1
+	}
+	if isConsonant {
+		consoCount = ppMaxRepeatedConsonant
+	}
+
+	segmentLen := 1
+
+	segmentLenTarget := ppSegmentLenMin + ppRandInt(rng, ppSegmentLenMax-ppSegmentLenMin)
+
+	for len(result) < pwlen {
+
+		charset := ppContinuation[currentChar]
+		if vowelCount >= ppMaxRepeatedVowel {
+			charset = ppCharsetRemove(charset, ppVowelMap, false)
+		}
+		if consoCount >= ppMaxRepeatedConsonant {
+			charset = ppCharsetRemove(charset, ppConsonantMap, false)
+		}
+
+		lastOfSegment := false
+		newSegment := false
+
+		if len(result)+1 == pwlen {
+			// last of result
+			charset = ppCharsetFilter(charset, ppEndCharMap, false)
+		} else if segmentLen+1 == segmentLenTarget {
+			// last of segment
+			charsetNew := ppCharsetFilter(charset, ppEndCharMap, true)
+			if charsetNew != "" {
+				charset = charsetNew
+				lastOfSegment = true
+			}
+		} else if segmentLen >= segmentLenTarget {
+			// (perhaps) start of new segment
+			if _, ok := ppEndCharMap[currentChar]; ok {
+				charset = ppStartChar
+				newSegment = true
+			} else {
+				// continue segment for one more char to (hopefully) find an end-char
+				charsetNew := ppCharsetFilter(charset, ppEndCharMap, true)
+				if charsetNew != "" {
+					charset = charsetNew
+					lastOfSegment = true
+				}
+			}
+		} else {
+			// normal continuation
+		}
+
+		newChar := ppRand(rng, charset, &entropy)
+		if lastOfSegment {
+			currentChar = newChar
+			segmentLen++
+			result += strings.ToLower(string(newChar))
+		} else if newSegment {
+			currentChar = newChar
+			segmentLen = 1
+			result += strings.ToUpper(string(newChar))
+			segmentLenTarget = ppSegmentLenMin + ppRandInt(rng, ppSegmentLenMax-ppSegmentLenMin)
+			vowelCount = 0
+			consoCount = 0
+		} else {
+			currentChar = newChar
+			segmentLen++
+			result += strings.ToLower(string(newChar))
+		}
+
+		isVowel, isConsonant := ppCharType(currentChar)
+		if isVowel {
+			vowelCount++
+			consoCount = 0
+		}
+		if isConsonant {
+			vowelCount = 0
+			if newSegment {
+				consoCount = ppMaxRepeatedConsonant
+			} else {
+				consoCount++
+			}
+		}
+	}
+
+	return result, entropy
+}
+
+func PronouncablePassword(len int) string {
+	v, _ := PronouncablePasswordExt(rand.Reader, len)
+	return v
+}
+
+func PronouncablePasswordSeeded(seed int64, len int) string {
+
+	v, _ := PronouncablePasswordExt(mathrand.New(mathrand.NewSource(seed)), len)
+	return v
+}

cryptext/pronouncablePassword_test.go

@@ -0,0 +1,35 @@
+package cryptext
+
+import (
+	"fmt"
+	"math/rand"
+	"testing"
+)
+
+func TestPronouncablePasswordExt(t *testing.T) {
+	for i := 0; i < 20; i++ {
+		pw, entropy := PronouncablePasswordExt(rand.New(rand.NewSource(int64(i))), 16)
+		fmt.Printf("[%.2f] => %s\n", entropy, pw)
+	}
+}
+
+func TestPronouncablePasswordSeeded(t *testing.T) {
+	for i := 0; i < 20; i++ {
+		pw := PronouncablePasswordSeeded(int64(i), 8)
+		fmt.Printf("%s\n", pw)
+	}
+}
+
+func TestPronouncablePassword(t *testing.T) {
+	for i := 0; i < 20; i++ {
+		pw := PronouncablePassword(i + 1)
+		fmt.Printf("%s\n", pw)
+	}
+}
+
+func TestPronouncablePasswordWrongLen(t *testing.T) {
+	PronouncablePassword(0)
+	PronouncablePassword(-1)
+	PronouncablePassword(-2)
+	PronouncablePassword(-3)
+}

goextVersion.go

@@ -1,5 +1,5 @@
 package goext
 
-const GoextVersion = "0.0.373"
+const GoextVersion = "0.0.374"
 
-const GoextVersionTimestamp = "2024-01-14T00:07:01+0100"
+const GoextVersionTimestamp = "2024-01-14T01:37:38+0100"