auth

Paddy 2015-01-18 Parent:c03b5eb3179e Child:118a69954621

119:3ec7134fa211 Go to Latest

auth/session.go

Exchange resource owner credentials for access token. Well, that was easy.

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paddy@70 1 package auth
paddy@70 2
paddy@70 3 import (
paddy@98 4 "crypto/sha256"
paddy@98 5 "encoding/hex"
paddy@119 6 "encoding/json"
paddy@70 7 "errors"
paddy@98 8 "log"
paddy@98 9 "net/http"
paddy@89 10 "sort"
paddy@70 11 "time"
paddy@70 12
paddy@107 13 "code.secondbit.org/pass.hg"
paddy@107 14 "code.secondbit.org/uuid.hg"
paddy@98 15 "github.com/gorilla/mux"
paddy@98 16 )
paddy@98 17
paddy@98 18 const (
paddy@98 19 loginTemplateName = "login"
paddy@70 20 )
paddy@70 21
paddy@119 22 func init() {
paddy@119 23 RegisterGrantType("password", GrantType{
paddy@119 24 Validate: credentialsValidate,
paddy@119 25 Invalidate: nil,
paddy@119 26 IssuesRefresh: true,
paddy@119 27 ReturnToken: RenderJSONToken,
paddy@119 28 })
paddy@119 29 }
paddy@119 30
paddy@70 31 var (
paddy@70 32 // ErrNoSessionStore is returned when a Context tries to act on a sessionStore without setting on first.
paddy@70 33 ErrNoSessionStore = errors.New("no sessionStore was specified for the Context")
paddy@70 34 // ErrSessionNotFound is returned when a Session is requested but not found in the sessionStore.
paddy@70 35 ErrSessionNotFound = errors.New("session not found in sessionStore")
paddy@70 36 // ErrInvalidSession is returned when a Session is specified but is not valid.
paddy@70 37 ErrInvalidSession = errors.New("session is not valid")
paddy@77 38 // ErrSessionAlreadyExists is returned when a sessionStore tries to store a Session with an ID that already exists in the sessionStore.
paddy@77 39 ErrSessionAlreadyExists = errors.New("session already exists")
paddy@98 40
paddy@98 41 passphraseSchemes = map[int]passphraseScheme{
paddy@98 42 1: {
paddy@98 43 check: pbkdf2sha256check,
paddy@98 44 create: pbkdf2sha256create,
paddy@98 45 calculateIterations: pbkdf2sha256calc,
paddy@98 46 },
paddy@98 47 }
paddy@70 48 )
paddy@70 49
paddy@98 50 type passphraseScheme struct {
paddy@98 51 check func(profile Profile, passphrase string) (bool, error)
paddy@103 52 create func(passphrase string, iterations int) (result, salt string, err error)
paddy@98 53 calculateIterations func() (int, error)
paddy@98 54 }
paddy@98 55
paddy@70 56 // Session represents a user's authenticated session, associating it with a profile
paddy@70 57 // and some audit data.
paddy@70 58 type Session struct {
paddy@70 59 ID string
paddy@70 60 IP string
paddy@70 61 UserAgent string
paddy@70 62 ProfileID uuid.ID
paddy@98 63 Login string
paddy@70 64 Created time.Time
paddy@70 65 Active bool
paddy@70 66 }
paddy@70 67
paddy@89 68 type sortedSessions []Session
paddy@89 69
paddy@89 70 func (s sortedSessions) Len() int {
paddy@89 71 return len(s)
paddy@89 72 }
paddy@89 73
paddy@89 74 func (s sortedSessions) Less(i, j int) bool {
paddy@89 75 return s[i].Created.After(s[j].Created)
paddy@89 76 }
paddy@89 77
paddy@89 78 func (s sortedSessions) Swap(i, j int) {
paddy@89 79 s[i], s[j] = s[j], s[i]
paddy@89 80 }
paddy@89 81
paddy@70 82 type sessionStore interface {
paddy@70 83 createSession(session Session) error
paddy@70 84 getSession(id string) (Session, error)
paddy@70 85 removeSession(id string) error
paddy@70 86 listSessions(profile uuid.ID, before time.Time, num int64) ([]Session, error)
paddy@70 87 }
paddy@77 88
paddy@77 89 func (m *memstore) createSession(session Session) error {
paddy@77 90 m.sessionLock.Lock()
paddy@77 91 defer m.sessionLock.Unlock()
paddy@77 92 if _, ok := m.sessions[session.ID]; ok {
paddy@77 93 return ErrSessionAlreadyExists
paddy@77 94 }
paddy@77 95 m.sessions[session.ID] = session
paddy@77 96 return nil
paddy@77 97 }
paddy@77 98
paddy@77 99 func (m *memstore) getSession(id string) (Session, error) {
paddy@77 100 m.sessionLock.RLock()
paddy@77 101 defer m.sessionLock.RUnlock()
paddy@77 102 if _, ok := m.sessions[id]; !ok {
paddy@77 103 return Session{}, ErrSessionNotFound
paddy@77 104 }
paddy@77 105 return m.sessions[id], nil
paddy@77 106 }
paddy@77 107
paddy@77 108 func (m *memstore) removeSession(id string) error {
paddy@77 109 m.sessionLock.Lock()
paddy@77 110 defer m.sessionLock.Unlock()
paddy@77 111 if _, ok := m.sessions[id]; !ok {
paddy@77 112 return ErrSessionNotFound
paddy@77 113 }
paddy@77 114 delete(m.sessions, id)
paddy@77 115 return nil
paddy@77 116 }
paddy@77 117
paddy@77 118 func (m *memstore) listSessions(profile uuid.ID, before time.Time, num int64) ([]Session, error) {
paddy@77 119 m.sessionLock.RLock()
paddy@77 120 defer m.sessionLock.RUnlock()
paddy@77 121 res := []Session{}
paddy@77 122 for _, session := range m.sessions {
paddy@77 123 if int64(len(res)) >= num {
paddy@77 124 break
paddy@77 125 }
paddy@77 126 if profile != nil && !profile.Equal(session.ProfileID) {
paddy@77 127 continue
paddy@77 128 }
paddy@77 129 if !before.IsZero() && session.Created.After(before) {
paddy@77 130 continue
paddy@77 131 }
paddy@77 132 res = append(res, session)
paddy@77 133 }
paddy@89 134 sorted := sortedSessions(res)
paddy@89 135 sort.Sort(sorted)
paddy@89 136 res = []Session(sorted)
paddy@77 137 return res, nil
paddy@77 138 }
paddy@98 139
paddy@98 140 // RegisterSessionHandlers adds handlers to the passed router to handle the session endpoints, like login and logout.
paddy@98 141 func RegisterSessionHandlers(r *mux.Router, context Context) {
paddy@98 142 r.Handle("/login", wrap(context, CreateSessionHandler))
paddy@98 143 }
paddy@98 144
paddy@98 145 func checkCookie(r *http.Request, context Context) (Session, error) {
paddy@98 146 cookie, err := r.Cookie(authCookieName)
paddy@98 147 if err == http.ErrNoCookie {
paddy@98 148 return Session{}, ErrNoSession
paddy@98 149 } else if err != nil {
paddy@98 150 log.Println(err)
paddy@98 151 return Session{}, err
paddy@98 152 }
paddy@98 153 sess, err := context.GetSession(cookie.Value)
paddy@98 154 if err == ErrSessionNotFound {
paddy@98 155 return Session{}, ErrInvalidSession
paddy@98 156 } else if err != nil {
paddy@98 157 return Session{}, err
paddy@98 158 }
paddy@98 159 if !sess.Active {
paddy@98 160 return Session{}, ErrInvalidSession
paddy@98 161 }
paddy@98 162 return sess, nil
paddy@98 163 }
paddy@98 164
paddy@98 165 func buildLoginRedirect(r *http.Request, context Context) string {
paddy@98 166 if context.loginURI == nil {
paddy@98 167 return ""
paddy@98 168 }
paddy@98 169 uri := *context.loginURI
paddy@98 170 q := uri.Query()
paddy@98 171 q.Set("from", r.URL.String())
paddy@98 172 uri.RawQuery = q.Encode()
paddy@98 173 return uri.String()
paddy@98 174 }
paddy@98 175
paddy@98 176 func pbkdf2sha256check(profile Profile, passphrase string) (bool, error) {
paddy@98 177 realPass, err := hex.DecodeString(profile.Passphrase)
paddy@98 178 if err != nil {
paddy@98 179 return false, err
paddy@98 180 }
paddy@103 181 realSalt, err := hex.DecodeString(profile.Salt)
paddy@103 182 if err != nil {
paddy@103 183 return false, err
paddy@103 184 }
paddy@103 185 candidate := pass.Check(sha256.New, profile.Iterations, []byte(passphrase), []byte(realSalt))
paddy@98 186 if !pass.Compare(candidate, realPass) {
paddy@98 187 return false, ErrIncorrectAuth
paddy@98 188 }
paddy@98 189 return true, nil
paddy@98 190 }
paddy@98 191
paddy@103 192 func pbkdf2sha256create(passphrase string, iters int) (result, salt string, err error) {
paddy@103 193 passBytes, saltBytes, err := pass.Create(sha256.New, iters, []byte(passphrase))
paddy@103 194 if err != nil {
paddy@103 195 return "", "", err
paddy@103 196 }
paddy@103 197 result = hex.EncodeToString(passBytes)
paddy@103 198 salt = hex.EncodeToString(saltBytes)
paddy@103 199 return result, salt, err
paddy@98 200 }
paddy@98 201
paddy@98 202 func pbkdf2sha256calc() (int, error) {
paddy@98 203 return pass.CalculateIterations(sha256.New)
paddy@98 204 }
paddy@98 205
paddy@98 206 func authenticate(user, passphrase string, context Context) (Profile, error) {
paddy@98 207 profile, err := context.GetProfileByLogin(user)
paddy@98 208 if err != nil {
paddy@98 209 if err == ErrProfileNotFound || err == ErrLoginNotFound {
paddy@98 210 return Profile{}, ErrIncorrectAuth
paddy@98 211 }
paddy@98 212 return Profile{}, err
paddy@98 213 }
paddy@98 214 if profile.Compromised {
paddy@98 215 return Profile{}, ErrProfileCompromised
paddy@98 216 }
paddy@98 217 if !profile.LockedUntil.IsZero() && profile.LockedUntil.After(time.Now()) {
paddy@98 218 return profile, ErrProfileLocked
paddy@98 219 }
paddy@98 220 scheme, ok := passphraseSchemes[profile.PassphraseScheme]
paddy@98 221 if !ok {
paddy@98 222 return Profile{}, ErrInvalidPassphraseScheme
paddy@98 223 }
paddy@98 224 result, err := scheme.check(profile, passphrase)
paddy@98 225 if !result {
paddy@98 226 return Profile{}, err
paddy@98 227 }
paddy@98 228 return profile, nil
paddy@98 229 }
paddy@98 230
paddy@98 231 // CreateSessionHandler allows the user to log into their account and create their session.
paddy@98 232 func CreateSessionHandler(w http.ResponseWriter, r *http.Request, context Context) {
paddy@98 233 // BUG(paddy): Creating a session needs CSRF protection, right? This whole thing should get a security audit
paddy@98 234 errors := []error{}
paddy@98 235 if r.Method == "POST" {
paddy@98 236 profile, err := authenticate(r.PostFormValue("login"), r.PostFormValue("passphrase"), context)
paddy@98 237 if err == nil {
paddy@98 238 ip := r.Header.Get("X-Forwarded-For")
paddy@98 239 if ip == "" {
paddy@98 240 ip = r.RemoteAddr
paddy@98 241 }
paddy@98 242 session := Session{
paddy@98 243 ID: uuid.NewID().String(),
paddy@98 244 IP: ip,
paddy@98 245 UserAgent: r.UserAgent(),
paddy@98 246 ProfileID: profile.ID,
paddy@98 247 Login: r.PostFormValue("login"),
paddy@98 248 Created: time.Now(),
paddy@98 249 Active: true,
paddy@98 250 }
paddy@98 251 err = context.CreateSession(session)
paddy@98 252 if err != nil {
paddy@98 253 w.WriteHeader(http.StatusInternalServerError)
paddy@98 254 w.Write([]byte(err.Error()))
paddy@98 255 return
paddy@98 256 }
paddy@98 257 // BUG(paddy): really need to do a security audit on our cookie
paddy@98 258 cookie := http.Cookie{
paddy@98 259 Name: authCookieName,
paddy@98 260 Value: session.ID,
paddy@98 261 Expires: time.Now().Add(24 * 7 * time.Hour),
paddy@98 262 HttpOnly: true,
paddy@98 263 }
paddy@98 264 http.SetCookie(w, &cookie)
paddy@98 265 redirectTo := r.URL.Query().Get("from")
paddy@98 266 if redirectTo == "" {
paddy@98 267 redirectTo = "/"
paddy@98 268 }
paddy@98 269 http.Redirect(w, r, redirectTo, http.StatusFound)
paddy@98 270 return
paddy@98 271 } else if err != ErrIncorrectAuth && err != ErrProfileCompromised && err != ErrProfileLocked {
paddy@98 272 w.WriteHeader(http.StatusInternalServerError)
paddy@98 273 w.Write([]byte(err.Error()))
paddy@98 274 return
paddy@98 275 } else {
paddy@98 276 errors = append(errors, err)
paddy@98 277 }
paddy@98 278 }
paddy@98 279 context.Render(w, loginTemplateName, map[string]interface{}{
paddy@98 280 "errors": errors,
paddy@98 281 })
paddy@98 282 }
paddy@119 283
paddy@119 284 func credentialsValidate(w http.ResponseWriter, r *http.Request, context Context) (scope string, profileID uuid.ID, valid bool) {
paddy@119 285 enc := json.NewEncoder(w)
paddy@119 286 username := r.PostFormValue("username")
paddy@119 287 password := r.PostFormValue("password")
paddy@119 288 scope = r.PostFormValue("scope")
paddy@119 289 profile, err := authenticate(username, password, context)
paddy@119 290 if err != nil {
paddy@119 291 if err == ErrIncorrectAuth || err == ErrProfileCompromised || err == ErrProfileLocked {
paddy@119 292 w.WriteHeader(http.StatusBadRequest)
paddy@119 293 renderJSONError(enc, "invalid_grant")
paddy@119 294 return
paddy@119 295 }
paddy@119 296 w.WriteHeader(http.StatusInternalServerError)
paddy@119 297 w.Write([]byte(err.Error()))
paddy@119 298 return
paddy@119 299 }
paddy@119 300 profileID = profile.ID
paddy@119 301 valid = true
paddy@119 302 return
paddy@119 303 }