.vscode/settings.json

@@ -0,0 +1,7 @@
+{
+    "cSpell.words": [
+        "hasher",
+        "htpasswd",
+        "Passwds"
+    ]
+}

go.mod

@@ -1,6 +1,6 @@
 module asciigoat.org/httools
 
-go 1.21.1
+go 1.20
 
 require github.com/mgechev/revive v1.3.3
 

go.sum

@@ -40,7 +40,6 @@ github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXl
 golang.org/x/crypto v0.13.0 h1:mvySKfSWJ+UKUii46M40LOvyWfN0s2U+46/jDd0e6Ck=
 golang.org/x/crypto v0.13.0/go.mod h1:y6Z2r+Rw4iayiXXAIxJIDAJ1zMW4yaTpebo8fPOliYc=
 golang.org/x/mod v0.12.0 h1:rmsUpXtvNzj340zd98LZ4KntptpfRHwpFOHG188oHXc=
-golang.org/x/mod v0.12.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
 golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.12.0 h1:CM0HF96J0hcLAwsHPJZjfdNzs0gftsLfgKt57wWHJ0o=
 golang.org/x/sys v0.12.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=

htpasswd/errors.go

@@ -0,0 +1,49 @@
+package htpasswd
+
+import (
+	"errors"
+	"strings"
+)
+
+var (
+	// ErrExists indicates the specified user already exists
+	ErrExists = errors.New("user already exists")
+	// ErrNotExists indicates the specified user does not exist
+	ErrNotExists = errors.New("user does not exist")
+	// ErrInvalidAlgorithm indicates the htpasswd entry doesn't contain a
+	// valid algorithm signature
+	ErrInvalidAlgorithm = errors.New("invalid algorithm")
+	// ErrInvalidPassword indicates the offered password doesn't match
+	ErrInvalidPassword = errors.New("invalid password")
+)
+
+// UserError indicates an error associated to the specified user
+type UserError struct {
+	Name string
+	Hint string
+	Err  error
+}
+
+func (e *UserError) Error() string {
+	var buf strings.Builder
+	var reason string
+
+	if e.Hint != "" {
+		reason = e.Hint
+	} else {
+		reason = e.Err.Error()
+	}
+
+	if e.Name == "" {
+		return reason
+	}
+
+	_, _ = buf.WriteString(e.Name)
+	_, _ = buf.WriteString(": ")
+	_, _ = buf.WriteString(reason)
+	return buf.String()
+}
+
+func (e *UserError) Unwrap() error {
+	return e.Err
+}

htpasswd/htpasswd.go

@@ -2,7 +2,6 @@
 package htpasswd
 
 import (
-	"errors"
 	"fmt"
 	"os"
 	"strings"
@@ -19,51 +18,53 @@ type Hasher interface {
 	Prefix() string
 }
 
-// ParseHtpasswdFile parses a .htpasswd file
+// ParseFile parses a .htpasswd file
 // and returns a Passwd type
-func ParseHtpasswdFile(file string) (Passwds, error) {
+func ParseFile(file string) (Passwds, error) {
 	htpasswdBytes, err := os.ReadFile(file)
 	if err != nil {
 		return nil, err
 	}
-	return ParseHtpasswd(htpasswdBytes)
+	return Parse(htpasswdBytes)
 }
 
-// ParseHtpasswd parses a slice of bytes in htpasswd style
+// Parse parses a slice of bytes in htpasswd style
-func ParseHtpasswd(htpasswdBytes []byte) (Passwds, error) {
+func Parse(htpasswdBytes []byte) (Passwds, error) {
 	lines := strings.Split(string(htpasswdBytes), "\n")
 	passwords := make(map[string]string)
 	var err error
 
 	for lineNumber, line := range lines {
-		line = strings.Trim(line, " ")
+		line = strings.TrimSpace(line)
 		if len(line) == 0 {
 			// skipping empty lines
 			continue
 		}
 
-		parts := strings.Split(line, ":")
+		user, password, err := splitLine(line, lineNumber)
-		if ok, err := validLine(parts, lineNumber, line); !ok {
+		if err != nil {
 			return passwords, err
 		}
 
-		parts = trimParts(parts)
+		_, exists := passwords[user]
-		_, exists := passwords[parts[0]]
-
 		if exists {
-			err = errors.New("invalid htpasswords file - user " +
+			err = &UserError{
-				parts[0] + " defined more than once")
+				Name: user,
+				Err:  ErrExists,
+			}
 			return passwords, err
 		}
-		passwords[parts[0]] = parts[1]
+
+		passwords[user] = password
 	}
+
 	return passwords, err
 }
 
 // CreateUser creates a record in the named file with
 // the named password and hash algorithm
 func CreateUser(file, user, passwd string, algo Hasher) error {
-	pp, err := ParseHtpasswdFile(file)
+	pp, err := ParseFile(file)
 	if err != nil {
 		return err
 	}
@@ -71,15 +72,19 @@ func CreateUser(file, user, passwd string, algo Hasher) error {
 	if err != nil {
 		return err
 	}
-	return pp.Write(file)
+	return pp.WriteFile(file)
 }
 
 // CreateUser will create a new user in the given Passwd object
 // using the given name, password and hashing algorithm
 func (pp Passwds) CreateUser(user, passwd string, algo Hasher) error {
 	if _, exists := pp[user]; exists {
-		return fmt.Errorf("user %s already exists", user)
+		return &UserError{
+			Name: user,
+			Err:  ErrExists,
+		}
 	}
+
 	h, err := algo.Hash(passwd)
 	if err != nil {
 		return err
@@ -91,7 +96,7 @@ func (pp Passwds) CreateUser(user, passwd string, algo Hasher) error {
 // UpdateUser will update the password for the named user
 // in the named file
 func UpdateUser(file, user, passwd string, algo Hasher) error {
-	pp, err := ParseHtpasswdFile(file)
+	pp, err := ParseFile(file)
 	if err != nil {
 		return err
 	}
@@ -99,15 +104,19 @@ func UpdateUser(file, user, passwd string, algo Hasher) error {
 	if err != nil {
 		return err
 	}
-	return pp.Write(file)
+	return pp.WriteFile(file)
 }
 
 // UpdateUser will update the password for the named user
 // using the given name, password and hashing algorithm
 func (pp Passwds) UpdateUser(user, passwd string, algo Hasher) error {
 	if _, exists := pp[user]; !exists {
-		return fmt.Errorf("user %s does not exist", user)
+		return &UserError{
+			Name: user,
+			Err:  ErrNotExists,
+		}
 	}
+
 	h, err := algo.Hash(passwd)
 	if err != nil {
 		return err
@@ -118,7 +127,7 @@ func (pp Passwds) UpdateUser(user, passwd string, algo Hasher) error {
 
 // DeleteUser deletes the named user from the named file
 func DeleteUser(file, user string) error {
-	pp, err := ParseHtpasswdFile(file)
+	pp, err := ParseFile(file)
 	if err != nil {
 		return err
 	}
@@ -127,13 +136,16 @@ func DeleteUser(file, user string) error {
 		return err
 	}
 
-	return pp.Write(file)
+	return pp.WriteFile(file)
 }
 
 // DeleteUser deletes the named user from the named file
 func (pp Passwds) DeleteUser(user string) error {
 	if _, exists := pp[user]; !exists {
-		return fmt.Errorf("user %s does not exist", user)
+		return &UserError{
+			Name: user,
+			Err:  ErrNotExists,
+		}
 	}
 
 	delete(pp, user)
@@ -143,7 +155,7 @@ func (pp Passwds) DeleteUser(user string) error {
 // VerifyUser will check if the given user and password are matching
 // with the content of the given file
 func VerifyUser(file, user, passwd string) error {
-	pp, err := ParseHtpasswdFile(file)
+	pp, err := ParseFile(file)
 	if err != nil {
 		return err
 	}
@@ -154,17 +166,25 @@ func VerifyUser(file, user, passwd string) error {
 // with the given Passwd object
 func (pp Passwds) VerifyUser(user, passwd string) error {
 	if _, ok := pp[user]; !ok {
-		return fmt.Errorf("user %s does not exist", user)
+		return &UserError{
+			Name: user,
+			Err:  ErrNotExists,
+		}
 	}
-	alg, err := identifyHash(pp[user])
+
-	if err != nil {
+	alg := identifyHash(pp[user])
-		return fmt.Errorf("cannot identify algo %v", alg)
+	if alg == nil {
+		return &UserError{
+			Name: user,
+			Err:  ErrInvalidAlgorithm,
+		}
 	}
+
 	return alg.Match(passwd, pp[user])
 }
 
-// Write will cwrite the Passwd object to the given file
+// WriteFile will write the Passwds object to the given file
-func (pp Passwds) Write(file string) error {
+func (pp Passwds) WriteFile(file string) error {
 	return os.WriteFile(file, pp.Bytes(), os.ModePerm)
 }
 
@@ -177,40 +197,38 @@ func (pp Passwds) Bytes() []byte {
 	return pass
 }
 
-func identifyHash(h string) (Hasher, error) {
+func identifyHash(h string) Hasher {
 	switch {
 	case strings.HasPrefix(h, "$2a$"), strings.HasPrefix(h, "$2y$"),
 		strings.HasPrefix(h, "$2x$"), strings.HasPrefix(h, "$2b$"):
-		return new(Bcrypt), nil
+		return new(Bcrypt)
 	case strings.HasPrefix(h, "$apr1$"):
-		return new(Apr1), nil
+		return new(Apr1)
 	case strings.HasPrefix(h, "{SHA}"):
-		return new(Sha), nil
+		return new(Sha)
 	case strings.HasPrefix(h, "{SSHA}"):
-		return new(Ssha), nil
+		return new(Ssha)
 	case strings.HasPrefix(h, "$5$"):
-		return new(Sha256), nil
+		return new(Sha256)
 	case strings.HasPrefix(h, "$6$"):
-		return new(Sha512), nil
+		return new(Sha512)
+	default:
+		return nil
 	}
-
-	return nil, fmt.Errorf("unsupported hash algorithm")
 }
 
-func validLine(parts []string, lineNumber int, line string) (bool, error) {
+func splitLine(line string, lineNumber int) (user, password string, err error) {
-	var err error
+	user, password, ok := strings.Cut(line, ":")
-	if len(parts) != 2 {
+	if !ok {
-		err = errors.New(fmt.Sprintln("invalid line", lineNumber+1,
+		return "", "", fmt.Errorf("invalid line %v", lineNumber+1)
-			"unexpected number of parts split by", ":", len(parts),
-			"instead of 2 in\"", line, "\""))
-		return false, err
 	}
-	return true, nil
-}
 
-func trimParts(parts []string) []string {
+	user = strings.TrimSpace(user)
-	for i, part := range parts {
+	password = strings.TrimSpace(password)
-		parts[i] = strings.Trim(part, " ")
+
+	if h := identifyHash(password); h != nil {
+		return "", "", fmt.Errorf("invalid algorithm on line %v", lineNumber+1)
 	}
-	return parts
+
+	return user, password, nil
 }

htpasswd/htpasswd_test.go

@@ -6,7 +6,7 @@ import (
 )
 
 func TestParseHtpasswd(t *testing.T) {
-	passwords, err := ParseHtpasswd([]byte("sha:{SHA}IRRjboXT92QSYXm8lpGPCZUvU1E=\n"))
+	passwords, err := Parse([]byte("sha:{SHA}IRRjboXT92QSYXm8lpGPCZUvU1E=\n"))
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -51,7 +51,7 @@ func TestVerifyPassword(t *testing.T) {
 		TestCreateUser(t)
 	}
 
-	_, err = ParseHtpasswdFile(f.Name())
+	_, err = ParseFile(f.Name())
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -83,7 +83,7 @@ func TestVerifyUser(t *testing.T) {
 		TestCreateUser(t)
 	}
 
-	pp, err := ParseHtpasswdFile(f.Name())
+	pp, err := ParseFile(f.Name())
 	if err != nil {
 		t.Fatal(err)
 	}