minio/docs/sts/web-identity.go
2021-08-18 18:35:22 -07:00

275 lines
7.7 KiB
Go

//go:build ignore
// +build ignore
// Copyright (c) 2015-2021 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package main
import (
"bytes"
"context"
"crypto/rand"
"encoding/base64"
"encoding/json"
"errors"
"flag"
"fmt"
"log"
"net/http"
"net/url"
"strings"
"time"
"golang.org/x/oauth2"
"github.com/minio/minio-go/v7"
"github.com/minio/minio-go/v7/pkg/credentials"
)
// Returns a base64 encoded random 32 byte string.
func randomState() string {
b := make([]byte, 32)
rand.Read(b)
return base64.RawURLEncoding.EncodeToString(b)
}
var (
stsEndpoint string
configEndpoint string
clientID string
clientSec string
clientScopes string
port int
)
// DiscoveryDoc - parses the output from openid-configuration
// for example http://localhost:8080/auth/realms/minio/.well-known/openid-configuration
type DiscoveryDoc struct {
Issuer string `json:"issuer,omitempty"`
AuthEndpoint string `json:"authorization_endpoint,omitempty"`
TokenEndpoint string `json:"token_endpoint,omitempty"`
UserInfoEndpoint string `json:"userinfo_endpoint,omitempty"`
RevocationEndpoint string `json:"revocation_endpoint,omitempty"`
JwksURI string `json:"jwks_uri,omitempty"`
ResponseTypesSupported []string `json:"response_types_supported,omitempty"`
SubjectTypesSupported []string `json:"subject_types_supported,omitempty"`
IDTokenSigningAlgValuesSupported []string `json:"id_token_signing_alg_values_supported,omitempty"`
ScopesSupported []string `json:"scopes_supported,omitempty"`
TokenEndpointAuthMethods []string `json:"token_endpoint_auth_methods_supported,omitempty"`
ClaimsSupported []string `json:"claims_supported,omitempty"`
CodeChallengeMethodsSupported []string `json:"code_challenge_methods_supported,omitempty"`
}
func parseDiscoveryDoc(ustr string) (DiscoveryDoc, error) {
d := DiscoveryDoc{}
req, err := http.NewRequest(http.MethodGet, ustr, nil)
if err != nil {
return d, err
}
clnt := http.Client{
Transport: http.DefaultTransport,
}
resp, err := clnt.Do(req)
if err != nil {
return d, err
}
defer resp.Body.Close()
if resp.StatusCode != http.StatusOK {
return d, err
}
dec := json.NewDecoder(resp.Body)
if err = dec.Decode(&d); err != nil {
return d, err
}
return d, nil
}
func init() {
flag.StringVar(&stsEndpoint, "sts-ep", "http://localhost:9000", "STS endpoint")
flag.StringVar(&configEndpoint, "config-ep",
"http://localhost:8080/auth/realms/minio/.well-known/openid-configuration",
"OpenID discovery document endpoint")
flag.StringVar(&clientID, "cid", "", "Client ID")
flag.StringVar(&clientSec, "csec", "", "Client Secret")
flag.StringVar(&clientScopes, "cscopes", "openid", "Client Scopes")
flag.IntVar(&port, "port", 8080, "Port")
}
func implicitFlowURL(c oauth2.Config, state string) string {
var buf bytes.Buffer
buf.WriteString(c.Endpoint.AuthURL)
v := url.Values{
"response_type": {"id_token"},
"response_mode": {"form_post"},
"client_id": {c.ClientID},
}
if c.RedirectURL != "" {
v.Set("redirect_uri", c.RedirectURL)
}
if len(c.Scopes) > 0 {
v.Set("scope", strings.Join(c.Scopes, " "))
}
v.Set("state", state)
v.Set("nonce", state)
if strings.Contains(c.Endpoint.AuthURL, "?") {
buf.WriteByte('&')
} else {
buf.WriteByte('?')
}
buf.WriteString(v.Encode())
return buf.String()
}
func main() {
flag.Parse()
if clientID == "" {
flag.PrintDefaults()
return
}
ddoc, err := parseDiscoveryDoc(configEndpoint)
if err != nil {
log.Println(fmt.Errorf("Failed to parse OIDC discovery document %s", err))
fmt.Println(err)
return
}
scopes := ddoc.ScopesSupported
if clientScopes != "" {
scopes = strings.Split(clientScopes, ",")
}
ctx := context.Background()
config := oauth2.Config{
ClientID: clientID,
ClientSecret: clientSec,
Endpoint: oauth2.Endpoint{
AuthURL: ddoc.AuthEndpoint,
TokenURL: ddoc.TokenEndpoint,
},
RedirectURL: fmt.Sprintf("http://10.0.0.67:%d/oauth2/callback", port),
Scopes: scopes,
}
state := randomState()
http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
log.Printf("%s %s", r.Method, r.RequestURI)
if r.RequestURI != "/" {
http.NotFound(w, r)
return
}
if clientSec != "" {
http.Redirect(w, r, config.AuthCodeURL(state), http.StatusFound)
} else {
http.Redirect(w, r, implicitFlowURL(config, state), http.StatusFound)
}
})
http.HandleFunc("/oauth2/callback", func(w http.ResponseWriter, r *http.Request) {
log.Printf("%s %s", r.Method, r.RequestURI)
if err := r.ParseForm(); err != nil {
http.Error(w, err.Error(), http.StatusBadRequest)
return
}
if r.Form.Get("state") != state {
http.Error(w, "state did not match", http.StatusBadRequest)
return
}
var getWebTokenExpiry func() (*credentials.WebIdentityToken, error)
if clientSec == "" {
getWebTokenExpiry = func() (*credentials.WebIdentityToken, error) {
return &credentials.WebIdentityToken{
Token: r.Form.Get("id_token"),
}, nil
}
} else {
getWebTokenExpiry = func() (*credentials.WebIdentityToken, error) {
oauth2Token, err := config.Exchange(ctx, r.URL.Query().Get("code"))
if err != nil {
return nil, err
}
if !oauth2Token.Valid() {
return nil, errors.New("invalid token")
}
return &credentials.WebIdentityToken{
Token: oauth2Token.Extra("id_token").(string),
Expiry: int(oauth2Token.Expiry.Sub(time.Now().UTC()).Seconds()),
}, nil
}
}
sts, err := credentials.NewSTSWebIdentity(stsEndpoint, getWebTokenExpiry)
if err != nil {
log.Println(fmt.Errorf("Could not get STS credentials: %s", err))
http.Error(w, err.Error(), http.StatusBadRequest)
return
}
opts := &minio.Options{
Creds: sts,
BucketLookup: minio.BucketLookupAuto,
}
u, err := url.Parse(stsEndpoint)
if err != nil {
log.Println(fmt.Errorf("Failed to parse STS Endpoint: %s", err))
http.Error(w, err.Error(), http.StatusBadRequest)
return
}
clnt, err := minio.New(u.Host, opts)
if err != nil {
log.Println(fmt.Errorf("Error while initializing Minio client, %s", err))
http.Error(w, err.Error(), http.StatusBadRequest)
return
}
buckets, err := clnt.ListBuckets(r.Context())
if err != nil {
log.Println(fmt.Errorf("Error while listing buckets, %s", err))
http.Error(w, err.Error(), http.StatusBadRequest)
return
}
creds, _ := sts.Get()
bucketNames := []string{}
for _, bucket := range buckets {
log.Println(fmt.Sprintf("Bucket discovered: %s", bucket.Name))
bucketNames = append(bucketNames, bucket.Name)
}
response := make(map[string]interface{})
response["credentials"] = creds
response["buckets"] = bucketNames
c, err := json.MarshalIndent(response, "", "\t")
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
w.Write(c)
})
address := fmt.Sprintf(":%v", port)
log.Printf("listening on http://%s/", address)
log.Fatal(http.ListenAndServe(address, nil))
}