Files
markdown-hub/internal/crypto/crypto.go
T
anders 68eaee0b9f Complete TODO items: security, features, polish
Security:
- Encrypt Gitea tokens at rest (AES-256-GCM with MH_SECRET)
- Secure cookie flag when behind HTTPS (X-Forwarded-Proto)
- Password complexity (min 8 chars)
- TOTP: defer persist until verified (totp_pending column)
- Audit log table + logging on login/rename/password change

Features:
- Rename files/folders (double-click in tree, /api/files/rename)
- beforeunload warning for unsaved changes
- Mobile hamburger menu
- PWA icons (192px, 512px)
- Max file size enforcement (10MB)
- Shared file read access (cross-user with permission check)

Polish:
- Toast notifications replace all alert() calls
- Keyboard shortcut help overlay (Ctrl+/)
- File rename via double-click in FileTree
2026-05-26 23:51:02 +02:00

95 lines
2.2 KiB
Go

package crypto
import (
"crypto/aes"
"crypto/cipher"
"crypto/rand"
"crypto/sha256"
"encoding/base64"
"errors"
"io"
"golang.org/x/crypto/argon2"
)
// DeriveKey derives a 256-bit key from password and salt using Argon2id.
func DeriveKey(password []byte, salt []byte) []byte {
return argon2.IDKey(password, salt, 3, 64*1024, 4, 32)
}
// KeyFromSecret derives a 256-bit AES key from a string secret (for token encryption).
func KeyFromSecret(secret string) []byte {
h := sha256.Sum256([]byte(secret))
return h[:]
}
// EncryptString encrypts a string and returns base64-encoded ciphertext.
func EncryptString(plaintext string, key []byte) (string, error) {
ct, err := Encrypt([]byte(plaintext), key)
if err != nil {
return "", err
}
return base64.StdEncoding.EncodeToString(ct), nil
}
// DecryptString decrypts a base64-encoded ciphertext to a string.
func DecryptString(encoded string, key []byte) (string, error) {
ct, err := base64.StdEncoding.DecodeString(encoded)
if err != nil {
return "", err
}
pt, err := Decrypt(ct, key)
if err != nil {
return "", err
}
return string(pt), nil
}
// GenerateSalt returns a random 16-byte salt.
func GenerateSalt() ([]byte, error) {
salt := make([]byte, 16)
_, err := io.ReadFull(rand.Reader, salt)
return salt, err
}
// Encrypt encrypts plaintext with AES-256-GCM using the given key.
func Encrypt(plaintext, key []byte) ([]byte, error) {
block, err := aes.NewCipher(key)
if err != nil {
return nil, err
}
gcm, err := cipher.NewGCM(block)
if err != nil {
return nil, err
}
nonce := make([]byte, gcm.NonceSize())
if _, err := io.ReadFull(rand.Reader, nonce); err != nil {
return nil, err
}
return gcm.Seal(nonce, nonce, plaintext, nil), nil
}
// Decrypt decrypts AES-256-GCM ciphertext using the given key.
func Decrypt(ciphertext, key []byte) ([]byte, error) {
block, err := aes.NewCipher(key)
if err != nil {
return nil, err
}
gcm, err := cipher.NewGCM(block)
if err != nil {
return nil, err
}
nonceSize := gcm.NonceSize()
if len(ciphertext) < nonceSize {
return nil, errors.New("ciphertext too short")
}
nonce, ciphertext := ciphertext[:nonceSize], ciphertext[nonceSize:]
return gcm.Open(nil, nonce, ciphertext, nil)
}