88 lines
2.7 KiB
Go
88 lines
2.7 KiB
Go
// Package auth handles password hashing, cookie sessions, CSRF
|
|
// protection, and optional trusted-reverse-proxy external authentication.
|
|
package auth
|
|
|
|
import (
|
|
"crypto/rand"
|
|
"crypto/subtle"
|
|
"encoding/base64"
|
|
"errors"
|
|
"fmt"
|
|
"strings"
|
|
|
|
"golang.org/x/crypto/argon2"
|
|
)
|
|
|
|
// Argon2id parameters, tuned for a self-hosted single/small-household
|
|
// server rather than a high-throughput multi-tenant service.
|
|
const (
|
|
argonTime = 1
|
|
argonMemory = 64 * 1024 // KiB
|
|
argonThreads = 4
|
|
argonKeyLen = 32
|
|
saltLen = 16
|
|
)
|
|
|
|
var ErrInvalidHash = errors.New("invalid password hash format")
|
|
|
|
// HashPassword returns an encoded argon2id hash in the standard
|
|
// $argon2id$v=19$m=...,t=...,p=...$salt$hash format.
|
|
func HashPassword(password string) (string, error) {
|
|
salt := make([]byte, saltLen)
|
|
if _, err := rand.Read(salt); err != nil {
|
|
return "", err
|
|
}
|
|
hash := argon2.IDKey([]byte(password), salt, argonTime, argonMemory, argonThreads, argonKeyLen)
|
|
b64Salt := base64.RawStdEncoding.EncodeToString(salt)
|
|
b64Hash := base64.RawStdEncoding.EncodeToString(hash)
|
|
return fmt.Sprintf("$argon2id$v=%d$m=%d,t=%d,p=%d$%s$%s", argon2.Version, argonMemory, argonTime, argonThreads, b64Salt, b64Hash), nil
|
|
}
|
|
|
|
// VerifyPassword checks password against an encoded hash produced by
|
|
// HashPassword, using constant-time comparison.
|
|
func VerifyPassword(password, encoded string) (bool, error) {
|
|
parts := strings.Split(encoded, "$")
|
|
if len(parts) != 6 || parts[1] != "argon2id" {
|
|
return false, ErrInvalidHash
|
|
}
|
|
var version int
|
|
if _, err := fmt.Sscanf(parts[2], "v=%d", &version); err != nil {
|
|
return false, ErrInvalidHash
|
|
}
|
|
var memory, timeCost uint32
|
|
var threads uint8
|
|
if _, err := fmt.Sscanf(parts[3], "m=%d,t=%d,p=%d", &memory, &timeCost, &threads); err != nil {
|
|
return false, ErrInvalidHash
|
|
}
|
|
salt, err := base64.RawStdEncoding.DecodeString(parts[4])
|
|
if err != nil {
|
|
return false, ErrInvalidHash
|
|
}
|
|
want, err := base64.RawStdEncoding.DecodeString(parts[5])
|
|
if err != nil {
|
|
return false, ErrInvalidHash
|
|
}
|
|
got := argon2.IDKey([]byte(password), salt, timeCost, memory, threads, uint32(len(want)))
|
|
return subtle.ConstantTimeCompare(got, want) == 1, nil
|
|
}
|
|
|
|
// GenerateRandomPassword returns a strong, human-typeable temporary
|
|
// password for the first-run administrator account.
|
|
func GenerateRandomPassword() (string, error) {
|
|
b := make([]byte, 18)
|
|
if _, err := rand.Read(b); err != nil {
|
|
return "", err
|
|
}
|
|
return base64.RawURLEncoding.EncodeToString(b), nil
|
|
}
|
|
|
|
// GenerateAPIKey returns a random API key and its SHA-256 hash for
|
|
// storage (the raw key is shown to the user only once).
|
|
func GenerateAPIKey() (raw string, err error) {
|
|
b := make([]byte, 32)
|
|
if _, err := rand.Read(b); err != nil {
|
|
return "", err
|
|
}
|
|
return "vs_" + base64.RawURLEncoding.EncodeToString(b), nil
|
|
}
|