mirror of
https://github.com/Luzifer/cloudkeys-go.git
synced 2024-11-14 00:42:44 +00:00
76 lines
2.7 KiB
Markdown
76 lines
2.7 KiB
Markdown
securecookie
|
|
============
|
|
[](https://godoc.org/github.com/gorilla/securecookie) [](https://travis-ci.org/gorilla/securecookie)
|
|
|
|
securecookie encodes and decodes authenticated and optionally encrypted
|
|
cookie values.
|
|
|
|
Secure cookies can't be forged, because their values are validated using HMAC.
|
|
When encrypted, the content is also inaccessible to malicious eyes. It is still
|
|
recommended that sensitive data not be stored in cookies, and that HTTPS be used
|
|
to prevent cookie [replay attacks](https://en.wikipedia.org/wiki/Replay_attack).
|
|
|
|
## Examples
|
|
|
|
To use it, first create a new SecureCookie instance:
|
|
|
|
```go
|
|
// Hash keys should be at least 32 bytes long
|
|
var hashKey = []byte("very-secret")
|
|
// Block keys should be 16 bytes (AES-128) or 32 bytes (AES-256) long.
|
|
// Shorter keys may weaken the encryption used.
|
|
var blockKey = []byte("a-lot-secret")
|
|
var s = securecookie.New(hashKey, blockKey)
|
|
```
|
|
|
|
The hashKey is required, used to authenticate the cookie value using HMAC.
|
|
It is recommended to use a key with 32 or 64 bytes.
|
|
|
|
The blockKey is optional, used to encrypt the cookie value -- set it to nil
|
|
to not use encryption. If set, the length must correspond to the block size
|
|
of the encryption algorithm. For AES, used by default, valid lengths are
|
|
16, 24, or 32 bytes to select AES-128, AES-192, or AES-256.
|
|
|
|
Strong keys can be created using the convenience function GenerateRandomKey().
|
|
|
|
Once a SecureCookie instance is set, use it to encode a cookie value:
|
|
|
|
```go
|
|
func SetCookieHandler(w http.ResponseWriter, r *http.Request) {
|
|
value := map[string]string{
|
|
"foo": "bar",
|
|
}
|
|
if encoded, err := s.Encode("cookie-name", value); err == nil {
|
|
cookie := &http.Cookie{
|
|
Name: "cookie-name",
|
|
Value: encoded,
|
|
Path: "/",
|
|
}
|
|
http.SetCookie(w, cookie)
|
|
}
|
|
}
|
|
```
|
|
|
|
Later, use the same SecureCookie instance to decode and validate a cookie
|
|
value:
|
|
|
|
```go
|
|
func ReadCookieHandler(w http.ResponseWriter, r *http.Request) {
|
|
if cookie, err := r.Cookie("cookie-name"); err == nil {
|
|
value := make(map[string]string)
|
|
if err = s2.Decode("cookie-name", cookie.Value, &value); err == nil {
|
|
fmt.Fprintf(w, "The value of foo is %q", value["foo"])
|
|
}
|
|
}
|
|
}
|
|
```
|
|
|
|
We stored a map[string]string, but secure cookies can hold any value that
|
|
can be encoded using `encoding/gob`. To store custom types, they must be
|
|
registered first using gob.Register(). For basic types this is not needed;
|
|
it works out of the box. An optional JSON encoder that uses `encoding/json` is
|
|
available for types compatible with JSON.
|
|
|
|
## License
|
|
|
|
BSD licensed. See the LICENSE file for details.
|