auth

Paddy 2015-01-18 Parent:e000b1c24fc0 Child:3ec7134fa211

117:da77e083cf02 Go to Latest

auth/oauth2.go

Change TODO to BUG. This is a refactor, not code to be added. It should show up in the gofmt bugs list.

Download raw file
View source Diff to previous Annotate
History
paddy@51 1 package auth
paddy@51 2
paddy@51 3 import (
paddy@69 4 "encoding/json"
paddy@69 5 "errors"
paddy@61 6 "html/template"
paddy@77 7 "log"
paddy@51 8 "net/http"
paddy@60 9 "net/url"
paddy@84 10 "sync"
paddy@60 11 "time"
paddy@56 12
paddy@107 13 "code.secondbit.org/uuid.hg"
paddy@82 14 "github.com/gorilla/mux"
paddy@51 15 )
paddy@51 16
paddy@60 17 const (
paddy@87 18 authCookieName = "auth"
paddy@87 19 defaultAuthorizationCodeExpiration = 600 // default to ten minute grant expirations
paddy@87 20 getAuthorizationCodeTemplateName = "get_grant"
paddy@60 21 )
paddy@51 22
paddy@69 23 var (
paddy@69 24 // ErrNoAuth is returned when an Authorization header is not present or is empty.
paddy@69 25 ErrNoAuth = errors.New("no authorization header supplied")
paddy@69 26 // ErrInvalidAuthFormat is returned when an Authorization header is present but not the correct format.
paddy@69 27 ErrInvalidAuthFormat = errors.New("authorization header is not in a valid format")
paddy@69 28 // ErrIncorrectAuth is returned when a user authentication attempt does not match the stored values.
paddy@69 29 ErrIncorrectAuth = errors.New("invalid authentication")
paddy@69 30 // ErrInvalidPassphraseScheme is returned when an undefined passphrase scheme is used.
paddy@69 31 ErrInvalidPassphraseScheme = errors.New("invalid passphrase scheme")
paddy@69 32 // ErrNoSession is returned when no session ID is passed with a request.
paddy@69 33 ErrNoSession = errors.New("no session ID found")
paddy@84 34
paddy@84 35 grantTypesMap = grantTypes{types: map[string]GrantType{}}
paddy@69 36 )
paddy@69 37
paddy@84 38 type grantTypes struct {
paddy@84 39 types map[string]GrantType
paddy@84 40 sync.RWMutex
paddy@84 41 }
paddy@84 42
paddy@84 43 // GrantType defines a set of functions and metadata around a specific authorization grant strategy.
paddy@84 44 //
paddy@84 45 // The Validate function will be called when requests are made that match the GrantType, and should write any
paddy@84 46 // errors to the ResponseWriter. It is responsible for determining if the grant is valid and a token should be issued.
paddy@84 47 // It must return the scope the grant was for and the ID of the Profile that issued the grant, as well as if the grant
paddy@84 48 // is valid or not. It must not be nil.
paddy@84 49 //
paddy@84 50 // The Invalidate function will be called when the grant has successfully generated a token and the token has successfully
paddy@84 51 // been conveyed to the user. The Invalidate function is always called asynchronously, outside the request. It should take
paddy@84 52 // care of marking the grant as used, if the GrantType requires grants to be one-time only grants. The Invalidate function
paddy@84 53 // can be nil.
paddy@84 54 //
paddy@84 55 // IssuesRefresh determines whether the GrantType should yield a refresh token as well as an access token. If true, the client
paddy@84 56 // will be issued a refresh token.
paddy@85 57 //
paddy@85 58 // The ReturnToken will be called when a token is created and needs to be returned to the client. If it returns true, the token
paddy@85 59 // was successfully returned and the Invalidate function will be called asynchronously.
paddy@84 60 type GrantType struct {
paddy@84 61 Validate func(w http.ResponseWriter, r *http.Request, context Context) (scope string, profileID uuid.ID, valid bool)
paddy@90 62 Invalidate func(r *http.Request, context Context) error
paddy@85 63 ReturnToken func(w http.ResponseWriter, r *http.Request, token Token, context Context) bool
paddy@84 64 IssuesRefresh bool
paddy@84 65 }
paddy@84 66
paddy@69 67 type tokenResponse struct {
paddy@69 68 AccessToken string `json:"access_token"`
paddy@69 69 TokenType string `json:"token_type,omitempty"`
paddy@69 70 ExpiresIn int32 `json:"expires_in,omitempty"`
paddy@69 71 RefreshToken string `json:"refresh_token,omitempty"`
paddy@69 72 }
paddy@69 73
paddy@82 74 type errorResponse struct {
paddy@82 75 Error string `json:"error"`
paddy@82 76 Description string `json:"error_description,omitempty"`
paddy@82 77 URI string `json:"error_uri,omitempty"`
paddy@82 78 }
paddy@82 79
paddy@84 80 // RegisterGrantType associates a string with a GrantType. When the string is used as the value for "grant_type" when obtaining
paddy@84 81 // an access token, the associated GrantType's properties will be used.
paddy@84 82 //
paddy@84 83 // RegisterGrantType should be called in the `init()` function of packages, much like database/sql registers drivers. It will panic
paddy@84 84 // if a GrantType tries to register under a string that already has a GrantType registered for it.
paddy@84 85 func RegisterGrantType(name string, g GrantType) {
paddy@84 86 grantTypesMap.Lock()
paddy@84 87 defer grantTypesMap.Unlock()
paddy@84 88 if _, ok := grantTypesMap.types[name]; ok {
paddy@84 89 panic("Duplicate registration of grant_type " + name)
paddy@84 90 }
paddy@84 91 grantTypesMap.types[name] = g
paddy@84 92 }
paddy@84 93
paddy@84 94 func findGrantType(name string) (GrantType, bool) {
paddy@84 95 grantTypesMap.RLock()
paddy@84 96 defer grantTypesMap.RUnlock()
paddy@84 97 t, ok := grantTypesMap.types[name]
paddy@84 98 return t, ok
paddy@84 99 }
paddy@84 100
paddy@82 101 func renderJSONError(enc *json.Encoder, errorType string) {
paddy@82 102 err := enc.Encode(errorResponse{
paddy@82 103 Error: errorType,
paddy@82 104 })
paddy@82 105 if err != nil {
paddy@90 106 log.Println(err)
paddy@69 107 }
paddy@69 108 }
paddy@69 109
paddy@86 110 // RenderJSONToken is an implementation of the ReturnToken function for GrantTypes. It returns the token using JSON
paddy@86 111 // according to the spec. See RFC 6479, Section 4.1.4.
paddy@85 112 func RenderJSONToken(w http.ResponseWriter, r *http.Request, token Token, context Context) bool {
paddy@85 113 enc := json.NewEncoder(w)
paddy@85 114 resp := tokenResponse{
paddy@85 115 AccessToken: token.AccessToken,
paddy@85 116 RefreshToken: token.RefreshToken,
paddy@85 117 ExpiresIn: token.ExpiresIn,
paddy@85 118 TokenType: token.TokenType,
paddy@85 119 }
paddy@109 120 w.Header().Set("Content-Type", "application/json")
paddy@85 121 err := enc.Encode(resp)
paddy@85 122 if err != nil {
paddy@90 123 log.Println(err)
paddy@85 124 return false
paddy@85 125 }
paddy@85 126 return true
paddy@85 127 }
paddy@85 128
paddy@77 129 // RegisterOAuth2 adds handlers to the passed router to handle the OAuth2 endpoints.
paddy@77 130 func RegisterOAuth2(r *mux.Router, context Context) {
paddy@87 131 r.Handle("/authorize", wrap(context, GetAuthorizationCodeHandler))
paddy@77 132 r.Handle("/token", wrap(context, GetTokenHandler))
paddy@77 133 }
paddy@77 134
paddy@87 135 // GetAuthorizationCodeHandler presents and processes the page for asking a user to grant access
paddy@57 136 // to their data. See RFC 6749, Section 4.1.
paddy@87 137 func GetAuthorizationCodeHandler(w http.ResponseWriter, r *http.Request, context Context) {
paddy@69 138 session, err := checkCookie(r, context)
paddy@69 139 if err != nil {
paddy@76 140 if err == ErrNoSession || err == ErrInvalidSession {
paddy@77 141 redir := buildLoginRedirect(r, context)
paddy@77 142 if redir == "" {
paddy@77 143 log.Println("No login URL configured.")
paddy@77 144 w.WriteHeader(http.StatusInternalServerError)
paddy@87 145 context.Render(w, getAuthorizationCodeTemplateName, map[string]interface{}{
paddy@77 146 "internal_error": template.HTML("Missing login URL."),
paddy@77 147 })
paddy@77 148 return
paddy@77 149 }
paddy@77 150 http.Redirect(w, r, redir, http.StatusFound)
paddy@77 151 return
paddy@69 152 }
paddy@77 153 log.Println(err.Error())
paddy@77 154 w.WriteHeader(http.StatusInternalServerError)
paddy@87 155 context.Render(w, getAuthorizationCodeTemplateName, map[string]interface{}{
paddy@77 156 "internal_error": template.HTML(err.Error()),
paddy@77 157 })
paddy@77 158 return
paddy@69 159 }
paddy@56 160 if r.URL.Query().Get("client_id") == "" {
paddy@56 161 w.WriteHeader(http.StatusBadRequest)
paddy@87 162 context.Render(w, getAuthorizationCodeTemplateName, map[string]interface{}{
paddy@61 163 "error": template.HTML("Client ID must be specified in the request."),
paddy@56 164 })
paddy@56 165 return
paddy@56 166 }
paddy@56 167 clientID, err := uuid.Parse(r.URL.Query().Get("client_id"))
paddy@56 168 if err != nil {
paddy@56 169 w.WriteHeader(http.StatusBadRequest)
paddy@87 170 context.Render(w, getAuthorizationCodeTemplateName, map[string]interface{}{
paddy@61 171 "error": template.HTML("client_id is not a valid Client ID."),
paddy@56 172 })
paddy@56 173 return
paddy@56 174 }
paddy@64 175 redirectURI := r.URL.Query().Get("redirect_uri")
paddy@56 176 client, err := context.GetClient(clientID)
paddy@56 177 if err != nil {
paddy@59 178 if err == ErrClientNotFound {
paddy@59 179 w.WriteHeader(http.StatusBadRequest)
paddy@87 180 context.Render(w, getAuthorizationCodeTemplateName, map[string]interface{}{
paddy@61 181 "error": template.HTML("The specified Client couldn’t be found."),
paddy@59 182 })
paddy@59 183 } else {
paddy@77 184 log.Println(err.Error())
paddy@59 185 w.WriteHeader(http.StatusInternalServerError)
paddy@87 186 context.Render(w, getAuthorizationCodeTemplateName, map[string]interface{}{
paddy@61 187 "internal_error": template.HTML(err.Error()),
paddy@59 188 })
paddy@59 189 }
paddy@56 190 return
paddy@56 191 }
paddy@117 192 // BUG(paddy): checking if the redirect URI is valid should be a helper function
paddy@56 193 // whether a redirect URI is valid or not depends on the number of endpoints
paddy@56 194 // the client has registered
paddy@56 195 numEndpoints, err := context.CountEndpoints(clientID)
paddy@56 196 if err != nil {
paddy@77 197 log.Println(err.Error())
paddy@56 198 w.WriteHeader(http.StatusInternalServerError)
paddy@87 199 context.Render(w, getAuthorizationCodeTemplateName, map[string]interface{}{
paddy@61 200 "internal_error": template.HTML(err.Error()),
paddy@56 201 })
paddy@56 202 return
paddy@56 203 }
paddy@56 204 var validURI bool
paddy@58 205 if redirectURI != "" {
paddy@58 206 validURI, err = context.CheckEndpoint(clientID, redirectURI)
paddy@56 207 if err != nil {
paddy@116 208 if err == ErrEndpointURINotURL {
paddy@116 209 w.WriteHeader(http.StatusBadRequest)
paddy@116 210 context.Render(w, getAuthorizationCodeTemplateName, map[string]interface{}{
paddy@116 211 "error": template.HTML("The redirect_uri specified is not valid."),
paddy@116 212 })
paddy@116 213 return
paddy@116 214 }
paddy@77 215 log.Println(err.Error())
paddy@56 216 w.WriteHeader(http.StatusInternalServerError)
paddy@87 217 context.Render(w, getAuthorizationCodeTemplateName, map[string]interface{}{
paddy@61 218 "internal_error": template.HTML(err.Error()),
paddy@56 219 })
paddy@56 220 return
paddy@56 221 }
paddy@56 222 } else if redirectURI == "" && numEndpoints == 1 {
paddy@56 223 // if we don't specify the endpoint and there's only one endpoint, the
paddy@56 224 // request is valid, and we're redirecting to that one endpoint
paddy@56 225 validURI = true
paddy@56 226 endpoints, err := context.ListEndpoints(clientID, 1, 0)
paddy@56 227 if err != nil {
paddy@77 228 log.Println(err.Error())
paddy@56 229 w.WriteHeader(http.StatusInternalServerError)
paddy@87 230 context.Render(w, getAuthorizationCodeTemplateName, map[string]interface{}{
paddy@61 231 "internal_error": template.HTML(err.Error()),
paddy@56 232 })
paddy@56 233 return
paddy@56 234 }
paddy@56 235 if len(endpoints) != 1 {
paddy@56 236 validURI = false
paddy@56 237 } else {
paddy@116 238 redirectURI = endpoints[0].URI
paddy@56 239 }
paddy@56 240 } else {
paddy@56 241 validURI = false
paddy@56 242 }
paddy@56 243 if !validURI {
paddy@56 244 w.WriteHeader(http.StatusBadRequest)
paddy@87 245 context.Render(w, getAuthorizationCodeTemplateName, map[string]interface{}{
paddy@61 246 "error": template.HTML("The redirect_uri specified is not valid."),
paddy@56 247 })
paddy@56 248 return
paddy@56 249 }
paddy@116 250 redirectURL, err := url.Parse(redirectURI)
paddy@116 251 if err != nil {
paddy@116 252 w.WriteHeader(http.StatusBadRequest)
paddy@116 253 context.Render(w, getAuthorizationCodeTemplateName, map[string]interface{}{
paddy@116 254 "error": template.HTML("The redirect_uri specified is not valid."),
paddy@116 255 })
paddy@116 256 return
paddy@116 257 }
paddy@60 258 scope := r.URL.Query().Get("scope")
paddy@60 259 state := r.URL.Query().Get("state")
paddy@56 260 if r.URL.Query().Get("response_type") != "code" {
paddy@65 261 q := redirectURL.Query()
paddy@65 262 q.Add("error", "invalid_request")
paddy@65 263 q.Add("state", state)
paddy@65 264 redirectURL.RawQuery = q.Encode()
paddy@60 265 http.Redirect(w, r, redirectURL.String(), http.StatusFound)
paddy@60 266 return
paddy@56 267 }
paddy@56 268 if r.Method == "POST" {
paddy@63 269 // BUG(paddy): We need to implement CSRF protection when obtaining a grant code.
paddy@56 270 if r.PostFormValue("grant") == "approved" {
paddy@60 271 code := uuid.NewID().String()
paddy@87 272 authCode := AuthorizationCode{
paddy@60 273 Code: code,
paddy@60 274 Created: time.Now(),
paddy@87 275 ExpiresIn: defaultAuthorizationCodeExpiration,
paddy@60 276 ClientID: clientID,
paddy@60 277 Scope: scope,
paddy@69 278 RedirectURI: r.URL.Query().Get("redirect_uri"),
paddy@60 279 State: state,
paddy@69 280 ProfileID: session.ProfileID,
paddy@60 281 }
paddy@87 282 err := context.SaveAuthorizationCode(authCode)
paddy@60 283 if err != nil {
paddy@66 284 q := redirectURL.Query()
paddy@66 285 q.Add("error", "server_error")
paddy@66 286 q.Add("state", state)
paddy@66 287 redirectURL.RawQuery = q.Encode()
paddy@60 288 http.Redirect(w, r, redirectURL.String(), http.StatusFound)
paddy@60 289 return
paddy@60 290 }
paddy@66 291 q := redirectURL.Query()
paddy@66 292 q.Add("code", code)
paddy@66 293 q.Add("state", state)
paddy@66 294 redirectURL.RawQuery = q.Encode()
paddy@60 295 http.Redirect(w, r, redirectURL.String(), http.StatusFound)
paddy@60 296 return
paddy@56 297 }
paddy@66 298 q := redirectURL.Query()
paddy@66 299 q.Add("error", "access_denied")
paddy@66 300 q.Add("state", state)
paddy@66 301 redirectURL.RawQuery = q.Encode()
paddy@60 302 http.Redirect(w, r, redirectURL.String(), http.StatusFound)
paddy@60 303 return
paddy@56 304 }
paddy@85 305 profile, err := context.GetProfileByID(session.ProfileID)
paddy@85 306 if err != nil {
paddy@85 307 q := redirectURL.Query()
paddy@85 308 q.Add("error", "server_error")
paddy@85 309 q.Add("state", state)
paddy@85 310 redirectURL.RawQuery = q.Encode()
paddy@85 311 http.Redirect(w, r, redirectURL.String(), http.StatusFound)
paddy@85 312 return
paddy@85 313 }
paddy@51 314 w.WriteHeader(http.StatusOK)
paddy@87 315 context.Render(w, getAuthorizationCodeTemplateName, map[string]interface{}{
paddy@85 316 "client": client,
paddy@85 317 "redirectURL": redirectURL,
paddy@85 318 "scope": scope,
paddy@85 319 "profile": profile,
paddy@56 320 })
paddy@51 321 }
paddy@68 322
paddy@69 323 // GetTokenHandler allows a client to exchange an authorization grant for an
paddy@69 324 // access token. See RFC 6749 Section 4.1.3.
paddy@69 325 func GetTokenHandler(w http.ResponseWriter, r *http.Request, context Context) {
paddy@69 326 enc := json.NewEncoder(w)
paddy@69 327 grantType := r.PostFormValue("grant_type")
paddy@84 328 gt, ok := findGrantType(grantType)
paddy@84 329 if !ok {
paddy@82 330 w.WriteHeader(http.StatusBadRequest)
paddy@82 331 renderJSONError(enc, "invalid_request")
paddy@69 332 return
paddy@69 333 }
paddy@84 334 scope, profileID, valid := gt.Validate(w, r, context)
paddy@84 335 if !valid {
paddy@69 336 return
paddy@69 337 }
paddy@84 338 refresh := ""
paddy@84 339 if gt.IssuesRefresh {
paddy@84 340 refresh = uuid.NewID().String()
paddy@69 341 }
paddy@69 342 token := Token{
paddy@88 343 AccessToken: uuid.NewID().String(),
paddy@88 344 RefreshToken: refresh,
paddy@88 345 Created: time.Now(),
paddy@88 346 ExpiresIn: defaultTokenExpiration,
paddy@88 347 RefreshExpiresIn: defaultRefreshTokenExpiration,
paddy@88 348 TokenType: "bearer",
paddy@88 349 Scope: scope,
paddy@88 350 ProfileID: profileID,
paddy@69 351 }
paddy@84 352 err := context.SaveToken(token)
paddy@69 353 if err != nil {
paddy@82 354 w.WriteHeader(http.StatusInternalServerError)
paddy@82 355 renderJSONError(enc, "server_error")
paddy@81 356 return
paddy@69 357 }
paddy@85 358 if gt.ReturnToken(w, r, token, context) && gt.Invalidate != nil {
paddy@85 359 go gt.Invalidate(r, context)
paddy@69 360 }
paddy@69 361 }
paddy@69 362
paddy@68 363 // TODO(paddy): exchange user credentials for access token
paddy@68 364 // TODO(paddy): exchange client credentials for access token
paddy@68 365 // TODO(paddy): implicit grant for access token
paddy@68 366 // TODO(paddy): exchange refresh token for access token