105 lines
2.5 KiB
Go
105 lines
2.5 KiB
Go
package main
|
|
|
|
import (
|
|
"crypto/rand"
|
|
"crypto/rsa"
|
|
"crypto/x509"
|
|
"encoding/pem"
|
|
"errors"
|
|
"log/slog"
|
|
"net/http"
|
|
"os"
|
|
"time"
|
|
|
|
"github.com/golang-jwt/jwt/v5"
|
|
)
|
|
|
|
var (
|
|
KeyFile = "private.key"
|
|
key *rsa.PrivateKey
|
|
)
|
|
|
|
// LoadKey attempts to load a private key from KeyFile.
|
|
// If the file does not exist, it generates a new key (and saves it)
|
|
func LoadKey() {
|
|
// If the key doesn't exist, create it
|
|
if _, err := os.Stat(KeyFile); errors.Is(err, os.ErrNotExist) {
|
|
key, err = rsa.GenerateKey(rand.Reader, 4096)
|
|
if err != nil {
|
|
slog.Error("error generating key", "error", err)
|
|
os.Exit(1)
|
|
}
|
|
|
|
// Save key to disk
|
|
km := x509.MarshalPKCS1PrivateKey(key)
|
|
block := pem.Block{Bytes: km, Type: "RSA PRIVATE KEY"}
|
|
f, err := os.OpenFile(KeyFile, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0644)
|
|
if err != nil {
|
|
slog.Error("error opening/creating file", "error", err)
|
|
os.Exit(1)
|
|
}
|
|
f.Write(pem.EncodeToMemory(&block))
|
|
if err := f.Close(); err != nil {
|
|
slog.Error("error closing file", "error", err)
|
|
os.Exit(1)
|
|
}
|
|
slog.Info("generated new key")
|
|
} else {
|
|
km, err := os.ReadFile(KeyFile)
|
|
if err != nil {
|
|
slog.Error("error reading key", "error", err)
|
|
os.Exit(1)
|
|
}
|
|
key, err = jwt.ParseRSAPrivateKeyFromPEM(km)
|
|
if err != nil {
|
|
slog.Error("error parsing key", "error", err)
|
|
os.Exit(1)
|
|
}
|
|
slog.Info("loaded private key")
|
|
}
|
|
}
|
|
|
|
// publicKey returns our public key as PEM block
|
|
func publicKey(w http.ResponseWriter, r *http.Request) {
|
|
key_marshalled := x509.MarshalPKCS1PublicKey(&key.PublicKey)
|
|
block := pem.Block{Bytes: key_marshalled, Type: "RSA PUBLIC KEY"}
|
|
pem.Encode(w, &block)
|
|
}
|
|
|
|
func CreateJWT(usr User) (string, error) {
|
|
t := jwt.NewWithClaims(jwt.SigningMethodRS256,
|
|
jwt.MapClaims{
|
|
"iss": "pye",
|
|
"uid": usr.Uuid,
|
|
"sub": usr.Email,
|
|
"iat": time.Now().Unix(),
|
|
"exp": time.Now().Add(time.Hour * 24 * 7).Unix(),
|
|
})
|
|
s, err := t.SignedString(key)
|
|
if err != nil {
|
|
slog.Error("error creating JWT", "error", err)
|
|
return "", err
|
|
}
|
|
return s, nil
|
|
}
|
|
|
|
// VerifyToken receives a JWT and PEM-encoded public key,
|
|
// then returns whether the token is valid
|
|
func VerifyJWT(token string, publicKey []byte) bool {
|
|
_, err := jwt.Parse(token, func(token *jwt.Token) (interface{}, error) {
|
|
key, err := jwt.ParseRSAPublicKeyFromPEM(publicKey)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if _, ok := token.Method.(*jwt.SigningMethodRSA); !ok {
|
|
return nil, err
|
|
}
|
|
return key, nil
|
|
})
|
|
slog.Info("Error check", "err", err)
|
|
return err == nil
|
|
}
|
|
|
|
func init() {
|
|
LoadKey()
|
|
}
|