diff options
Diffstat (limited to 'guides')
-rw-r--r-- | guides/source/configuring.md | 8 | ||||
-rw-r--r-- | guides/source/security.md | 23 |
2 files changed, 21 insertions, 10 deletions
diff --git a/guides/source/configuring.md b/guides/source/configuring.md index bf9456a482..6a7eaf00e1 100644 --- a/guides/source/configuring.md +++ b/guides/source/configuring.md @@ -456,10 +456,14 @@ to `'http authentication'`. Defaults to `'signed cookie'`. * `config.action_dispatch.encrypted_cookie_salt` sets the encrypted cookies salt -value. Defaults to `'encrypted cookie'`. + value. Defaults to `'encrypted cookie'`. * `config.action_dispatch.encrypted_signed_cookie_salt` sets the signed -encrypted cookies salt value. Defaults to `'signed encrypted cookie'`. + encrypted cookies salt value. Defaults to `'signed encrypted cookie'`. + +* `config.action_dispatch.authenticated_encrypted_cookie_salt` sets the + authenticated encrypted cookie salt. Defaults to `'authenticated encrypted + cookie'`. * `config.action_dispatch.perform_deep_munge` configures whether `deep_munge` method should be performed on the parameters. See [Security Guide](security.html#unsafe-query-generation) diff --git a/guides/source/security.md b/guides/source/security.md index 75522834df..f69a0c72b0 100644 --- a/guides/source/security.md +++ b/guides/source/security.md @@ -95,16 +95,23 @@ Rails 2 introduced a new default session storage, CookieStore. CookieStore saves * The client can see everything you store in a session, because it is stored in clear-text (actually Base64-encoded, so not encrypted). So, of course, _you don't want to store any secrets here_. To prevent session hash tampering, a digest is calculated from the session with a server-side secret (`secrets.secret_token`) and inserted into the end of the cookie. -However, since Rails 4, the default store is EncryptedCookieStore. With -EncryptedCookieStore the session is encrypted before being stored in a cookie. -This prevents the user from accessing and tampering the content of the cookie. -Thus the session becomes a more secure place to store data. The encryption is -done using a server-side secret key `secrets.secret_key_base` stored in -`config/secrets.yml`. +In Rails 4, encrypted cookies through AES in CBC mode with HMAC using SHA1 for +verification was introduced. This prevents the user from accessing and tampering +the content of the cookie. Thus the session becomes a more secure place to store +data. The encryption is performed using a server-side `secrets.secret_key_base`. +Two salts are used when deriving keys for encryption and verification. These +salts are set via the `config.action_dispatch.encrypted_cookie_salt` and +`config.action_dispatch.encrypted_signed_cookie_salt` configuration values. -That means the security of this storage depends on this secret (and on the digest algorithm, which defaults to SHA1, for compatibility). So _don't use a trivial secret, i.e. a word from a dictionary, or one which is shorter than 30 characters, use `rails secret` instead_. +Rails 5.2 uses AES-GCM for the encryption which couples authentication +and encryption in one faster step and produces shorter ciphertexts. -`secrets.secret_key_base` is used for specifying a key which allows sessions for the application to be verified against a known secure key to prevent tampering. Applications get `secrets.secret_key_base` initialized to a random key present in `config/secrets.yml`, e.g.: +Encrypted cookies are automatically upgraded if the +`config.action_dispatch.use_authenticated_cookie_encryption` is enabled. + +_Do not use a trivial secret, i.e. a word from a dictionary, or one which is shorter than 30 characters! Instead use `rails secret` to generate secret keys!_ + +Applications get `secrets.secret_key_base` initialized to a random key present in `config/secrets.yml`, e.g.: development: secret_key_base: a75d... |