apg-go/apg.go
Winni Neessen 2a970b9bce
v0.2.2: Minor fixes and testing
- Replaced log.Fatal() with log.Fatalf() since we provide %v
- Added proper testing and benchmarking
2021-03-20 18:31:32 +01:00

138 lines
3.7 KiB
Go

package main
import (
"crypto/rand"
"flag"
"fmt"
"log"
"math/big"
"os"
"regexp"
)
// Constants
const DefaultPwLenght int = 20
const VersionString string = "0.2.2"
const PwLowerCharsHuman string = "abcdefghjkmnpqrstuvwxyz"
const PwUpperCharsHuman string = "ABCDEFGHJKMNPQRSTUVWXYZ"
const PwLowerChars string = "abcdefghijklmnopqrstuvwxyz"
const PwUpperChars string = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
const PwSpecialCharsHuman string = "\"#/\\$%&+-*"
const PwSpecialChars string = "\"#/!\\$%&+-*.,?=()[]{}:;~^|"
const PwNumbersHuman string = "23456789"
const PwNumbers string = "1234567890"
type cliOpts struct {
minPassLen int
maxPassLen int
numOfPass int
useComplex bool
useLowerCase bool
useUpperCase bool
useNumber bool
useSpecial bool
humanReadable bool
excludeChars string
showHelp bool
showVersion bool
}
var config cliOpts
// Read flags
func init() {
// Bool flags
flag.BoolVar(&config.useLowerCase, "L", true, "Use lower case characters in passwords")
flag.BoolVar(&config.useUpperCase, "U", false, "Use upper case characters in passwords")
flag.BoolVar(&config.useNumber, "N", false, "Use numbers in passwords")
flag.BoolVar(&config.useSpecial, "S", false, "Use special characters in passwords")
flag.BoolVar(&config.useComplex, "C", true, "Generate complex passwords (implies -L -U -N -S, disables -H)")
flag.BoolVar(&config.humanReadable, "H", false, "Generate human-readable passwords")
flag.BoolVar(&config.showVersion, "v", false, "Show version")
// Int flags
flag.IntVar(&config.minPassLen, "m", 10, "Minimum password length")
flag.IntVar(&config.maxPassLen, "x", DefaultPwLenght, "Maxiumum password length")
flag.IntVar(&config.numOfPass, "n", 1, "Number of passwords to generate")
// String flags
flag.StringVar(&config.excludeChars, "E", "", "Exclude list of characters from generated password")
flag.Parse()
if config.showVersion {
_, _ = os.Stderr.WriteString("Advanced Password Generator v" + VersionString + "\n")
os.Exit(0)
}
}
func main() {
pwLength := config.minPassLen
if pwLength < config.minPassLen {
pwLength = config.minPassLen
}
if pwLength > config.maxPassLen {
pwLength = config.maxPassLen
}
if config.useComplex {
config.useUpperCase = true
config.useLowerCase = true
config.useSpecial = true
config.useNumber = true
config.humanReadable = false
}
pwUpperChars := PwUpperChars
pwLowerChars := PwLowerChars
pwNumbers := PwNumbers
pwSpecialChars := PwSpecialChars
if config.humanReadable {
pwUpperChars = PwUpperCharsHuman
pwLowerChars = PwLowerCharsHuman
pwNumbers = PwNumbersHuman
pwSpecialChars = PwSpecialCharsHuman
}
var charRange string
if config.useLowerCase {
charRange = charRange + pwLowerChars
}
if config.useUpperCase {
charRange = charRange + pwUpperChars
}
if config.useNumber {
charRange = charRange + pwNumbers
}
if config.useSpecial {
charRange = charRange + pwSpecialChars
}
if config.excludeChars != "" {
regExp := regexp.MustCompile("[" + config.excludeChars + "]")
charRange = regExp.ReplaceAllLiteralString(charRange, "")
}
for i := 1; i <= config.numOfPass; i++ {
pwString := getRandChar(&charRange, pwLength)
fmt.Println(pwString)
}
}
func getRandChar(charRange *string, pwLength int) string {
availCharsLength := len(*charRange)
charSlice := []byte(*charRange)
returnString := []byte{}
for i := 0; i < pwLength; i++ {
randNum := getRandNum(availCharsLength)
returnString = append(returnString, charSlice[randNum])
}
return string(returnString)
}
func getRandNum(maxNum int) int {
maxNumBigInt := big.NewInt(int64(maxNum))
randNum64, err := rand.Int(rand.Reader, maxNumBigInt)
if err != nil {
log.Fatalf("An error occured generating random number: %v", err)
}
randNum := int(randNum64.Int64())
return randNum
}