caddy/modules/caddyhttp/caddyauth/caddyauth.go

128 lines
3.8 KiB
Go

// Copyright 2015 Matthew Holt and The Caddy Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package caddyauth
import (
"fmt"
"net/http"
"go.uber.org/zap"
"go.uber.org/zap/zapcore"
"github.com/caddyserver/caddy/v2"
"github.com/caddyserver/caddy/v2/modules/caddyhttp"
)
func init() {
caddy.RegisterModule(Authentication{})
}
// Authentication is a middleware which provides user authentication.
// Rejects requests with HTTP 401 if the request is not authenticated.
//
// After a successful authentication, the placeholder
// `{http.auth.user.id}` will be set to the username, and also
// `{http.auth.user.*}` placeholders may be set for any authentication
// modules that provide user metadata.
//
// Its API is still experimental and may be subject to change.
type Authentication struct {
// A set of authentication providers. If none are specified,
// all requests will always be unauthenticated.
ProvidersRaw caddy.ModuleMap `json:"providers,omitempty" caddy:"namespace=http.authentication.providers"`
Providers map[string]Authenticator `json:"-"`
logger *zap.Logger
}
// CaddyModule returns the Caddy module information.
func (Authentication) CaddyModule() caddy.ModuleInfo {
return caddy.ModuleInfo{
ID: "http.handlers.authentication",
New: func() caddy.Module { return new(Authentication) },
}
}
// Provision sets up a.
func (a *Authentication) Provision(ctx caddy.Context) error {
a.logger = ctx.Logger()
a.Providers = make(map[string]Authenticator)
mods, err := ctx.LoadModule(a, "ProvidersRaw")
if err != nil {
return fmt.Errorf("loading authentication providers: %v", err)
}
for modName, modIface := range mods.(map[string]any) {
a.Providers[modName] = modIface.(Authenticator)
}
return nil
}
func (a Authentication) ServeHTTP(w http.ResponseWriter, r *http.Request, next caddyhttp.Handler) error {
var user User
var authed bool
var err error
for provName, prov := range a.Providers {
user, authed, err = prov.Authenticate(w, r)
if err != nil {
if c := a.logger.Check(zapcore.ErrorLevel, "auth provider returned error"); c != nil {
c.Write(zap.String("provider", provName), zap.Error(err))
}
continue
}
if authed {
break
}
}
if !authed {
return caddyhttp.Error(http.StatusUnauthorized, fmt.Errorf("not authenticated"))
}
repl := r.Context().Value(caddy.ReplacerCtxKey).(*caddy.Replacer)
repl.Set("http.auth.user.id", user.ID)
for k, v := range user.Metadata {
repl.Set("http.auth.user."+k, v)
}
return next.ServeHTTP(w, r)
}
// Authenticator is a type which can authenticate a request.
// If a request was not authenticated, it returns false. An
// error is only returned if authenticating the request fails
// for a technical reason (not for bad/missing credentials).
type Authenticator interface {
Authenticate(http.ResponseWriter, *http.Request) (User, bool, error)
}
// User represents an authenticated user.
type User struct {
// The ID of the authenticated user.
ID string
// Any other relevant data about this
// user. Keys should be adhere to Caddy
// conventions (snake_casing), as all
// keys will be made available as
// placeholders.
Metadata map[string]string
}
// Interface guards
var (
_ caddy.Provisioner = (*Authentication)(nil)
_ caddyhttp.MiddlewareHandler = (*Authentication)(nil)
)