Files
remark42/backend/vendor/github.com/go-pkgz/auth/provider/service.go
T

248 lines
6.6 KiB
Go

package provider
import (
"context"
"crypto/rand"
"crypto/sha1"
"encoding/json"
"fmt"
"io/ioutil"
"log"
"net/http"
"strings"
"time"
jwt "github.com/dgrijalva/jwt-go"
"github.com/go-pkgz/rest"
"github.com/pkg/errors"
"golang.org/x/oauth2"
"github.com/go-pkgz/auth/avatar"
"github.com/go-pkgz/auth/token"
)
// Service represents oauth2 provider
type Service struct {
Params
Name string
RedirectURL string
InfoURL string
Endpoint oauth2.Endpoint
Scopes []string
MapUser func(userData, []byte) token.User // map info from InfoURL to User
conf oauth2.Config
}
// Params to make initialized and ready to use provider
type Params struct {
URL string
JwtService *token.Service
AvatarProxy *avatar.Proxy
Cid string
Csecret string
Issuer string
}
type userData map[string]interface{}
func (u userData) value(key string) string {
// json.Unmarshal converts json "null" value to go's "nil", in this case return empty string
if val, ok := u[key]; ok && val != nil {
return fmt.Sprintf("%v", val)
}
return ""
}
// initService makes token service for given provider
func initService(p Params, service Service) Service {
log.Printf("[INFO] init token service %s", service.Name)
service.Params = p
service.conf = oauth2.Config{
ClientID: service.Cid,
ClientSecret: service.Csecret,
RedirectURL: service.RedirectURL,
Scopes: service.Scopes,
Endpoint: service.Endpoint,
}
log.Printf("[DEBUG] created %s token, id=%s, redir=%s, endpoint=%s",
service.Name, service.Cid, service.Endpoint, service.RedirectURL)
return service
}
// Handler returns auth routes for given provider
func (p Service) Handler(w http.ResponseWriter, r *http.Request) {
if r.Method != "GET" {
w.WriteHeader(http.StatusMethodNotAllowed)
return
}
if strings.HasSuffix(r.URL.Path, "/login") {
p.loginHandler(w, r)
return
}
if strings.HasSuffix(r.URL.Path, "/callback") {
p.authHandler(w, r)
return
}
if strings.HasSuffix(r.URL.Path, "/logout") {
p.LogoutHandler(w, r)
return
}
w.WriteHeader(http.StatusNotFound)
}
// loginHandler - GET /login?from=redirect-back-url&site=siteID&session=1
func (p Service) loginHandler(w http.ResponseWriter, r *http.Request) {
log.Printf("[DEBUG] login with %s", p.Name)
// make state (random) and store in session
state, err := p.randToken()
if err != nil {
rest.SendErrorJSON(w, r, http.StatusInternalServerError, err, "failed to make oauth2 state")
return
}
cid, err := p.randToken()
if err != nil {
rest.SendErrorJSON(w, r, http.StatusInternalServerError, err, "failed to make claim's id")
return
}
claims := token.Claims{
Handshake: &token.Handshake{
State: state,
From: r.URL.Query().Get("from"),
},
SessionOnly: r.URL.Query().Get("session") != "" && r.URL.Query().Get("session") != "0",
StandardClaims: jwt.StandardClaims{
Id: cid,
Audience: r.URL.Query().Get("site"),
ExpiresAt: time.Now().Add(30 * time.Minute).Unix(),
NotBefore: time.Now().Add(-1 * time.Minute).Unix(),
},
}
if err := p.JwtService.Set(w, claims, false); err != nil {
rest.SendErrorJSON(w, r, http.StatusInternalServerError, err, "failed to set token")
return
}
// return login url
loginURL := p.conf.AuthCodeURL(state)
log.Printf("[DEBUG] login url %s, claims=%+v", loginURL, claims)
http.Redirect(w, r, loginURL, http.StatusFound)
}
// authHandler fills user info and redirects to "from" url. This is callback url redirected locally by browser
// GET /callback
func (p Service) authHandler(w http.ResponseWriter, r *http.Request) {
oauthClaims, _, err := p.JwtService.Get(r)
if err != nil {
rest.SendErrorJSON(w, r, http.StatusInternalServerError, err, "failed to get token")
return
}
retrievedState := oauthClaims.Handshake.State
if retrievedState == "" || retrievedState != r.URL.Query().Get("state") {
http.Error(w, fmt.Sprintf("unexpected state %v", retrievedState), http.StatusUnauthorized)
return
}
log.Printf("[DEBUG] token with state %s", retrievedState)
tok, err := p.conf.Exchange(context.Background(), r.URL.Query().Get("code"))
if err != nil {
rest.SendErrorJSON(w, r, http.StatusInternalServerError, err, "exchange failed")
return
}
client := p.conf.Client(context.Background(), tok)
uinfo, err := client.Get(p.InfoURL)
if err != nil {
rest.SendErrorJSON(w, r, http.StatusBadRequest, err, fmt.Sprintf("failed to get client info via %s", p.InfoURL))
return
}
defer func() {
if e := uinfo.Body.Close(); e != nil {
log.Printf("[WARN] failed to close response body, %s", e)
}
}()
data, err := ioutil.ReadAll(uinfo.Body)
if err != nil {
rest.SendErrorJSON(w, r, http.StatusInternalServerError, err, "failed to read user info")
return
}
jData := map[string]interface{}{}
if e := json.Unmarshal(data, &jData); e != nil {
rest.SendErrorJSON(w, r, http.StatusInternalServerError, err, "failed to unmarshal user info")
return
}
log.Printf("[DEBUG] got raw user info %+v", jData)
u := p.MapUser(jData, data)
u = p.setAvatar(u)
cid, err := p.randToken()
if err != nil {
rest.SendErrorJSON(w, r, http.StatusInternalServerError, err, "failed to make claim's id")
return
}
claims := token.Claims{
User: &u,
StandardClaims: jwt.StandardClaims{
Issuer: p.Issuer,
Id: cid,
Audience: oauthClaims.Audience,
},
SessionOnly: oauthClaims.SessionOnly,
}
if err = p.JwtService.Set(w, claims, oauthClaims.SessionOnly); err != nil {
rest.SendErrorJSON(w, r, http.StatusInternalServerError, err, "failed to save user info")
return
}
log.Printf("[DEBUG] user info %+v", u)
// redirect to back url if presented in login query params
if oauthClaims.Handshake != nil && oauthClaims.Handshake.From != "" {
http.Redirect(w, r, oauthClaims.Handshake.From, http.StatusTemporaryRedirect)
return
}
rest.RenderJSON(w, r, &u)
}
// setAvatar saves avatar and puts proxied URL to u.Picture
func (p Service) setAvatar(u token.User) token.User {
if p.AvatarProxy != nil {
if avatarURL, e := p.AvatarProxy.Put(u); e == nil {
u.Picture = avatarURL
} else {
log.Printf("[WARN] failed to set avatar for %+v, %+v", u, e)
}
}
return u
}
// LogoutHandler - GET /logout
func (p Service) LogoutHandler(w http.ResponseWriter, r *http.Request) {
p.JwtService.Reset(w)
log.Printf("[DEBUG] logout")
}
func (p Service) randToken() (string, error) {
b := make([]byte, 32)
if _, err := rand.Read(b); err != nil {
return "", errors.Wrap(err, "can't get random")
}
s := sha1.New()
if _, err := s.Write(b); err != nil {
return "", errors.Wrap(err, "can't write randoms to sha1")
}
return fmt.Sprintf("%x", s.Sum(nil)), nil
}