mox/vendor/github.com/mjl-/sherpa
Mechiel Lukkien 0f8bf2f220
replace http basic auth for web interfaces with session cookie & csrf-based auth
the http basic auth we had was very simple to reason about, and to implement.
but it has a major downside:

there is no way to logout, browsers keep sending credentials. ideally, browsers
themselves would show a button to stop sending credentials.

a related downside: the http auth mechanism doesn't indicate for which server
paths the credentials are.

another downside: the original password is sent to the server with each
request. though sending original passwords to web servers seems to be
considered normal.

our new approach uses session cookies, along with csrf values when we can. the
sessions are server-side managed, automatically extended on each use. this
makes it easy to invalidate sessions and keeps the frontend simpler (than with
long- vs short-term sessions and refreshing). the cookies are httponly,
samesite=strict, scoped to the path of the web interface. cookies are set
"secure" when set over https. the cookie is set by a successful call to Login.
a call to Logout invalidates a session. changing a password invalidates all
sessions for a user, but keeps the session with which the password was changed
alive. the csrf value is also random, and associated with the session cookie.
the csrf must be sent as header for api calls, or as parameter for direct form
posts (where we cannot set a custom header). rest-like calls made directly by
the browser, e.g. for images, don't have a csrf protection. the csrf value is
returned by the Login api call and stored in localstorage.

api calls without credentials return code "user:noAuth", and with bad
credentials return "user:badAuth". the api client recognizes this and triggers
a login. after a login, all auth-failed api calls are automatically retried.
only for "user:badAuth" is an error message displayed in the login form (e.g.
session expired).

in an ideal world, browsers would take care of most session management. a
server would indicate authentication is needed (like http basic auth), and the
browsers uses trusted ui to request credentials for the server & path. the
browser could use safer mechanism than sending original passwords to the
server, such as scram, along with a standard way to create sessions.  for now,
web developers have to do authentication themselves: from showing the login
prompt, ensuring the right session/csrf cookies/localstorage/headers/etc are
sent with each request.

webauthn is a newer way to do authentication, perhaps we'll implement it in the
future. though hardware tokens aren't an attractive option for many users, and
it may be overkill as long as we still do old-fashioned authentication in smtp
& imap where passwords can be sent to the server.

for issue #58
2024-01-05 10:48:42 +01:00
..
.gitignore mox! 2023-01-30 14:27:06 +01:00
codes.go mox! 2023-01-30 14:27:06 +01:00
collector.go mox! 2023-01-30 14:27:06 +01:00
doc.go mox! 2023-01-30 14:27:06 +01:00
handler.go replace http basic auth for web interfaces with session cookie & csrf-based auth 2024-01-05 10:48:42 +01:00
intstr.go mox! 2023-01-30 14:27:06 +01:00
isclosed.go mox! 2023-01-30 14:27:06 +01:00
isclosed_plan9.go mox! 2023-01-30 14:27:06 +01:00
LICENSE mox! 2023-01-30 14:27:06 +01:00
LICENSE-go mox! 2023-01-30 14:27:06 +01:00
Makefile mox! 2023-01-30 14:27:06 +01:00
README.md mox! 2023-01-30 14:27:06 +01:00
sherpajs.go mox! 2023-01-30 14:27:06 +01:00

Sherpa

Sherpa is a Go library for creating a sherpa API.

This library makes it trivial to export Go functions as a sherpa API with an http.Handler.

Your API will automatically be documented: github.com/mjl-/sherpadoc reads your Go source, and exports function and type comments as API documentation.

See the documentation.

Examples

A public sherpa API: https://www.sherpadoc.org/#https://www.sherpadoc.org/example/

That web application is sherpaweb. It shows documentation for any sherpa API but also includes an API called Example for demo purposes.

Ding is a more elaborate web application built with this library.

About

Written by Mechiel Lukkien, mechiel@ueber.net. Bug fixes, patches, comments are welcome. MIT-licensed, see LICENSE.

todo

  • add a toggle for enabling calls by GET request. turn off by default for functions with parameters, people might be making requests with sensitive information in query strings...
  • include a sherpaweb-like page that displays the documentation
  • consider adding input & output validation and timestamp conversion to plain js lib
  • consider using interfaces with functions (instead of direct structs) for server implementations. haven't needed it yet, but could be useful for mocking an api that you want to talk to.
  • think about way to keep unknown fields. perhaps use a json lib that collects unknown keys in a map (which has to be added to the object for which you want to keep such keys).
  • sherpajs: make a versionied, minified variant, with license line
  • tool for comparing two jsons for compatibility, listing added sections/functions/types/fields
  • be more helpful around errors that functions can generate. perhaps adding a mechanism for listing which errors can occur in the api json.
  • handler: write tests
  • client: write tests