Some guidelines in designing the new validation API
* Previously, the `Valid` method was placed on the claim, which was always not entirely semantically correct, since the validity is concerning the token, not the claims. Although the validity of the token is based on the processing of the claims (such as `exp`). Therefore, the function `Valid` was removed from the `Claims` interface and the single canonical way to retrieve the validity of the token is to retrieve the `Valid` property of the `Token` struct.
* The previous fact was enhanced by the fact that most claims implementations had additional exported `VerifyXXX` functions, which are now removed
* All validation errors should be comparable with `errors.Is` to determine, why a particular validation has failed
* Developers want to adjust validation options. Popular options include:
* Leeway when processing exp, nbf, iat
* Not verifying `iat`, since this is actually just an informational claim. When purely looking at the standard, this should probably the default
* Verifying `aud` by default, which actually the standard sort of demands. We need to see how strong we want to enforce this
* Developers want to create their own claim types, mostly by embedding one of the existing types such as `RegisteredClaims`.
* Sometimes there is the need to further tweak the validation of a token by checking the value of a custom claim. Previously, this was possibly by overriding `Valid`. However, this was error-prone, e.g., if the original `Valid` was not called. Therefore, we should provide an easy way for *additional* checks, without by-passing the necessary validations
This leads to the following two major changes:
* The `Claims` interface now represents a set of functions that return the mandatory claims represented in a token, rather than just a `Valid` function. This is also more semantically correct.
* All validation tasks are offloaded to a new (optional) `Validator`, which can also be configured with appropriate options. If no custom validator was supplied, a default one is used.
This commit serves as the basis for further `v5` developments. It will introduce some API-breaking changes, especially to the way tokens are validated. This will allow us to provide some long-wanted features with regards to the validation API. We are aiming to do this as smoothly as possible, however, with any major version. please expect that you might need to adapt your code.
The actual development will be done in the course of the next week, if time permits. It will be done in seperate PRs that will use this PR as a base. Afterwards, we will probably merge this and release an initial 5.0.0-alpha1 or similar.
* Implement a BearerExtractor
This is a rather common extractor; it extracts the JWT from the HTTP
Authorization header, expecting it to include the "Bearer " prefix.
This patterns is rather common and this snippet is repeated in enough
applications that it's probably best to just include it upstream and
allow reusing it.
* Ignore case-sensitivity for "Bearer"
* updated README.md to contain more extensions
* Update README.md
Co-authored-by: Luis Gabriel Gomez <lggomez@users.noreply.github.com>
Co-authored-by: Luis Gabriel Gomez <lggomez@users.noreply.github.com>
* improve code comments, including security consideration
* Add link to URL with details about security vulnerabilities.
* Update token.go
Co-authored-by: Christian Banse <oxisto@aybaze.com>
* Update token.go
Co-authored-by: Christian Banse <oxisto@aybaze.com>
* update code comments
Co-authored-by: Christian Banse <oxisto@aybaze.com>
* accept generic crypto.Signer in ed25519 in order to allow usage of other ed25519 providers than crypto/ed25519
* add check to ensure the key is indeed of type ed25519
* adding comment clarifying crypto.Hash(0)
* Update ed25519.go
Co-authored-by: Christian Banse <oxisto@aybaze.com>
This PR aims at implementing compliance to RFC7519, as documented in #11 without breaking the public API. It creates a new struct `RegisteredClaims` and deprecates (but not removes) the `StandardClaims`. It introduces a new type `NumericDate`, which represents a JSON numeric date value as specified in the RFC. This allows us to handle float as well as int-based time fields in `aud`, `exp` and `nbf`. Additionally, it introduces the type `StringArray`, which is basically a wrapper around `[]string` to deal with the oddities of the JWT `aud` field.
Christian Banse