Updated PBKDF2 hasher with more complex format handling

go.mod

@@ -1,6 +1,6 @@
 module github.com/iegomez/mosquitto-go-auth
 
-go 1.18
+go 1.21
 
 require (
 	github.com/go-redis/redis/v8 v8.11.5

go.sum

@@ -16,6 +16,7 @@ github.com/envoyproxy/go-control-plane v0.9.1-0.20191026205805-5f8ba28d4473/go.m
 github.com/envoyproxy/go-control-plane v0.9.4/go.mod h1:6rpuAdCZL397s3pYoYcLgu1mIlRU8Am5FuJP05cCM98=
 github.com/envoyproxy/protoc-gen-validate v0.1.0/go.mod h1:iSmxcyjqTsJpI2R4NaDN7+kN2VEUnK/pcBlmesArF7c=
 github.com/fsnotify/fsnotify v1.4.9 h1:hsms1Qyu0jgnwNXIxa+/V/PDsU6CfLf6CNO8H7IWoS4=
+github.com/fsnotify/fsnotify v1.4.9/go.mod h1:znqG4EE+3YCdAaPaxE2ZRY/06pZUdp0tY4IgpuI1SZQ=
 github.com/go-kit/log v0.1.0/go.mod h1:zbhenjAZHb184qTLMA9ZjW7ThYL0H2mk7Q6pNt4vbaY=
 github.com/go-logfmt/logfmt v0.5.0/go.mod h1:wCYkCAKZfumFQihp8CzCvQ3paCTfi41vtzG1KdI/P7A=
 github.com/go-redis/redis/v8 v8.11.5 h1:AcZZR7igkdvfVmQTPnu9WE37LRrO/YrBH5zWyjDC0oI=
@@ -43,6 +44,7 @@ github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5a
 github.com/google/go-cmp v0.5.2/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
+github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/gopherjs/gopherjs v0.0.0-20181017120253-0766667cb4d1/go.mod h1:wJfORRmW1u3UXTncJ5qlYoELFm8eSnnEO6hX4iZ3EWY=
 github.com/gopherjs/gopherjs v0.0.0-20190328170749-bb2674552d8f h1:4Gslotqbs16iAg+1KR/XdabIfq8TlAWHdwS5QJFksLc=
 github.com/gopherjs/gopherjs v0.0.0-20190328170749-bb2674552d8f/go.mod h1:wJfORRmW1u3UXTncJ5qlYoELFm8eSnnEO6hX4iZ3EWY=
@@ -73,8 +75,11 @@ github.com/montanaflynn/stats v0.0.0-20171201202039-1bf9dbcd8cbe/go.mod h1:wL8QJ
 github.com/montanaflynn/stats v0.7.1 h1:etflOAAHORrCC44V+aR6Ftzort912ZU+YLiSTuV8eaE=
 github.com/montanaflynn/stats v0.7.1/go.mod h1:etXPPgVO6n31NxCd9KQUMvCM+ve0ruNzt6R8Bnaayow=
 github.com/nxadm/tail v1.4.8 h1:nPr65rt6Y5JFSKQO7qToXr7pePgD6Gwiw05lkbyAQTE=
+github.com/nxadm/tail v1.4.8/go.mod h1:+ncqLTQzXmGhMZNUePPaPqPvBxHAIsmXswZKocGu+AU=
 github.com/onsi/ginkgo v1.16.5 h1:8xi0RTUf59SOSfEtZMvwTvXYMzG4gV23XVHOZiXNtnE=
+github.com/onsi/ginkgo v1.16.5/go.mod h1:+E8gABHa3K6zRBolWtd+ROzc/U5bkGt0FwiG042wbpU=
 github.com/onsi/gomega v1.18.1 h1:M1GfJqGRrBrrGGsbxzV5dqM2U2ApXefZCQpkukxYRLE=
+github.com/onsi/gomega v1.18.1/go.mod h1:0q+aL8jAiMXy9hbwj2mr5GziHiwhAIQpFmmtT5hitRs=
 github.com/opentracing/opentracing-go v1.1.0/go.mod h1:UkNAQd3GIcIGf0SeVgPpRdFStlNbqXla1AfSYxPUl2o=
 github.com/patrickmn/go-cache v2.1.0+incompatible h1:HRMgzkcYKYpi3C8ajMPV8OFXaaRUnok+kx1WdO15EQc=
 github.com/patrickmn/go-cache v2.1.0+incompatible/go.mod h1:3Qf8kWWT7OJRJbdiICTKqZju1ZixQ/KpMGzzAfe6+WQ=
@@ -231,9 +236,11 @@ gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15/go.mod h1:Co6ibVJAznAaIkqp8
 gopkg.in/sourcemap.v1 v1.0.5 h1:inv58fC9f9J3TK2Y2R1NPntXEn3/wjWHkonhIUODNTI=
 gopkg.in/sourcemap.v1 v1.0.5/go.mod h1:2RlvNNSMglmRrcvhfuzp4hQHwOtjxlbjX7UPY/GXb78=
 gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7 h1:uRGJdciOHaEIrze2W8Q3AKkepLTh2hOroT7a+7czfdQ=
+gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7/go.mod h1:dt/ZhP58zS4L8KSrWDmTeBkI65Dw0HsyUHuEVlX15mw=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.8/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
+gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=

hashing/hashing_test.go

@@ -126,22 +126,29 @@ func TestArgon2ID(t *testing.T) {
 
 func TestPBKDF2(t *testing.T) {
 	password := "test-password"
-
-	// Test base64.
-	hasher := NewPBKDF2Hasher(defaultPBKDF2SaltSize, defaultPBKDF2Iterations, defaultPBKDF2Algorithm, Base64, defaultPBKDF2KeyLen)
-
-	passwordHash, err := hasher.Hash(password)
-
-	assert.Nil(t, err)
-	assert.True(t, hasher.Compare(password, passwordHash))
-	assert.False(t, hasher.Compare("other", passwordHash))
-
-	// Test UTF8.
-	hasher = NewPBKDF2Hasher(defaultPBKDF2SaltSize, defaultPBKDF2Iterations, defaultPBKDF2Algorithm, UTF8, defaultPBKDF2KeyLen)
-
-	passwordHash, err = hasher.Hash(password)
-
-	assert.Nil(t, err)
-	assert.True(t, hasher.Compare(password, passwordHash))
-	assert.False(t, hasher.Compare("other", passwordHash))
+	b64Hasher := NewPBKDF2Hasher(defaultPBKDF2SaltSize, defaultPBKDF2Iterations, defaultPBKDF2Algorithm, Base64, defaultPBKDF2KeyLen)
+	utf8Hasher := NewPBKDF2Hasher(defaultPBKDF2SaltSize, defaultPBKDF2Iterations, defaultPBKDF2Algorithm, UTF8, defaultPBKDF2KeyLen)
+
+	t.Run("OlderFormat", func(t *testing.T) {
+		t.Run("Base64", func(t *testing.T) {
+			passwordHash, err := b64Hasher.Hash(password)
+
+			assert.Nil(t, err)
+			assert.True(t, b64Hasher.Compare(password, passwordHash))
+			assert.False(t, b64Hasher.Compare("other", passwordHash))
+		})
+		t.Run("UTF8", func(t *testing.T) {
+			passwordHash, err := utf8Hasher.Hash(password)
+
+			assert.Nil(t, err)
+			assert.True(t, utf8Hasher.Compare(password, passwordHash))
+			assert.False(t, utf8Hasher.Compare("other", passwordHash))
+		})
+	})
+
+	t.Run("PHC-SF-Spec", func(t *testing.T) {
+		passwordHash := "$pbkdf2-sha512$i=10000,l=32$/DsNR8DBuoF/MxzLY+QVaw$YNfYNfT+6yT2blLrXKKR8Ll+aesgHYqSOtFTBsyscRM"
+		assert.True(t, b64Hasher.Compare(password, passwordHash))
+		assert.False(t, b64Hasher.Compare("other", passwordHash))
+	})
 }

hashing/pbkdf2.go

@@ -8,6 +8,7 @@ import (
 	"encoding/base64"
 	"fmt"
 	"math/big"
+	"slices"
 	"strconv"
 	"strings"
 
@@ -23,34 +24,32 @@ type pbkdf2Hasher struct {
 	keyLen       int
 }
 
-func NewPBKDF2Hasher(saltSize int, iterations int, algorithm string, saltEncoding string, keylen int) HashComparer {
+func NewPBKDF2Hasher(saltSize int, iterations int, algorithm string, saltEncoding string, keyLen int) HashComparer {
 	return pbkdf2Hasher{
 		saltSize:     saltSize,
 		iterations:   iterations,
 		algorithm:    algorithm,
 		saltEncoding: preferredEncoding(saltEncoding),
-		keyLen:       keylen,
+		keyLen:       keyLen,
 	}
 }
 
 /*
 * PBKDF2 methods are adapted from github.com/brocaar/chirpstack-application-server, some comments included.
  */
 
-// Hash function reference may be found at https://github.com/brocaar/chirpstack-application-server/blob/master/internal/storage/user.go#L421.
-
-// Generate the hash of a password for storage in the database.
-// NOTE: We store the details of the hashing algorithm with the hash itself,
-// making it easy to recreate the hash for password checking, even if we change
-// the default criteria here.
+// Hash function generates a hash of the supplied password. The hash
+// can then be stored directly in the database. The return hash will
+// contain options according to the PHC String format found at
+// https://github.com/P-H-C/phc-string-format/blob/master/phc-sf-spec.md
 func (h pbkdf2Hasher) Hash(password string) (string, error) {
 	// Generate a random salt value with the given salt size.
 	salt := make([]byte, h.saltSize)
 	_, err := rand.Read(salt)
 
-	// We need to ensure that salt doesn contain $, which is 36 in decimal.
-	// So we check if there'sbyte that represents $ and change it with a random number in the range 0-35
-	//// This is far from ideal, but should be good enough with a reasonable salt size.
+	// We need to ensure that salt doesn't contain $, which is 36 in decimal.
+	// So we check if there's byte that represents $ and change it with a random number in the range 0-35
+	// // This is far from ideal, but should be good enough with a reasonable salt size.
 	for i := 0; i < len(salt); i++ {
 		if salt[i] == 36 {
 			n, err := rand.Int(rand.Reader, big.NewInt(35))
@@ -69,52 +68,116 @@ func (h pbkdf2Hasher) Hash(password string) (string, error) {
 	return h.hashWithSalt(password, salt, h.iterations, h.algorithm, h.keyLen), nil
 }
 
-// HashCompare verifies that passed password hashes to the same value as the
+// Compare verifies that passed password hashes to the same value as the
 // passed passwordHash.
 // Reference: https://github.com/brocaar/chirpstack-application-server/blob/master/internal/storage/user.go#L458.
+// Parsing reference: https://github.com/P-H-C/phc-string-format/blob/master/phc-sf-spec.md
 func (h pbkdf2Hasher) Compare(password string, passwordHash string) bool {
-	hashSplit := strings.Split(passwordHash, "$")
-
-	if len(hashSplit) != 5 {
-		log.Errorf("invalid PBKDF2 hash supplied, expected length 5, got: %d", len(hashSplit))
-		return false
-	}
-
-	algorithm := hashSplit[1]
+	hashSplit := h.getFields(passwordHash)
+
+	var (
+		err            error
+		algorithm      string
+		paramString    string
+		hashedPassword []byte
+		salt           []byte
+		iterations     int
+		keyLen         int
+	)
+	if hashSplit[0] == "PBKDF2" {
+		algorithm = hashSplit[1]
+		iterations, err = strconv.Atoi(hashSplit[2])
+		if err != nil {
+			log.Errorf("iterations error: %s", err)
+			return false
+		}
 
-	iterations, err := strconv.Atoi(hashSplit[2])
-	if err != nil {
-		log.Errorf("iterations error: %s", err)
-		return false
-	}
+		switch h.saltEncoding {
+		case UTF8:
+			salt = []byte(hashSplit[3])
+		default:
+			var err error
+			salt, err = base64.StdEncoding.DecodeString(hashSplit[3])
+			if err != nil {
+				log.Errorf("base64 salt error: %s", err)
+				return false
+			}
+		}
 
-	var salt []byte
-	switch h.saltEncoding {
-	case UTF8:
-		salt = []byte(hashSplit[3])
-	default:
-		salt, err = base64.StdEncoding.DecodeString(hashSplit[3])
+		hashedPassword, err = base64.StdEncoding.DecodeString(hashSplit[4])
 		if err != nil {
-			log.Errorf("base64 salt error: %s", err)
+			log.Errorf("base64 hash decoding error: %s", err)
 			return false
 		}
+		keyLen = len(hashedPassword)
+
+	} else if hashSplit[0] == "pbkdf2-sha512" {
+		algorithm = "sha512"
+		paramString = hashSplit[1]
+
+		opts := strings.Split(paramString, ",")
+		for _, opt := range opts {
+			parts := strings.Split(opt, "=")
+			for i := 0; i < len(parts); i += 2 {
+				key := parts[i]
+				val := parts[i+1]
+				switch key {
+				case "i":
+					iterations, _ = strconv.Atoi(val)
+				case "l":
+					keyLen, _ = strconv.Atoi(val)
+				default:
+					log.Errorf("unknown options key (\"%s\")", key)
+					return false
+				}
+			}
+		}
+
+		switch h.saltEncoding {
+		case UTF8:
+			salt = []byte(hashSplit[2])
+		default:
+			var err error
+			salt, err = base64.StdEncoding.WithPadding(base64.NoPadding).DecodeString(hashSplit[2])
+			if err != nil {
+				log.Errorf("base64 salt error: %s", err)
+				return false
+			}
+		}
+
+		hashedPassword, err = base64.StdEncoding.WithPadding(base64.NoPadding).DecodeString(hashSplit[3])
+	} else {
+		log.Errorf("invalid PBKDF2 hash supplied, unrecognized format \"%s\"", hashSplit[0])
+		return false
 	}
 
-	hashedPassword, err := base64.StdEncoding.DecodeString(hashSplit[4])
+	newHash := h.hashWithSalt(password, salt, iterations, algorithm, keyLen)
+	hashSplit = h.getFields(newHash)
+	newHashedPassword, err := base64.StdEncoding.DecodeString(hashSplit[4])
 	if err != nil {
-		log.Errorf("base64 hash decoding error: %s", err)
+		log.Errorf("base64 salt error: %s", err)
 		return false
 	}
 
-	keylen := len(hashedPassword)
+	return slices.Compare(hashedPassword, newHashedPassword) == 0
+}
 
-	return passwordHash == h.hashWithSalt(password, salt, iterations, algorithm, keylen)
+func (h pbkdf2Hasher) getFields(passwordHash string) []string {
+	hashSplit := strings.FieldsFunc(passwordHash, func(r rune) bool {
+		switch r {
+		case '$':
+			return true
+		default:
+			return false
+		}
+	})
+	return hashSplit
 }
 
 // Reference: https://github.com/brocaar/chirpstack-application-server/blob/master/internal/storage/user.go#L432.
 func (h pbkdf2Hasher) hashWithSalt(password string, salt []byte, iterations int, algorithm string, keylen int) string {
 	// Generate the hashed password. This should be a little painful, adjust ITERATIONS
-	// if it needs performance tweeking.  Greatly depends on the hardware.
+	// if it needs performance tweaking.  Greatly depends on the hardware.
 	// NOTE: We store these details with the returned hashed, so changes will not
 	// affect our ability to do password compares.
 	shaHash := sha512.New