forked from
tangled.org/core
Monorepo for Tangled
1package state
2
3import (
4 "errors"
5 "fmt"
6 "net/http"
7 "strings"
8 "time"
9
10 comatproto "github.com/bluesky-social/indigo/api/atproto"
11 "github.com/bluesky-social/indigo/xrpc"
12 "tangled.org/core/appview/pages"
13)
14
15func (s *State) Login(w http.ResponseWriter, r *http.Request) {
16 l := s.logger.With("handler", "Login")
17
18 switch r.Method {
19 case http.MethodGet:
20 returnURL := r.URL.Query().Get("return_url")
21 errorCode := r.URL.Query().Get("error")
22 addAccount := r.URL.Query().Get("mode") == "add_account"
23
24 registry := s.oauth.GetAccounts(r)
25 s.pages.Login(w, pages.LoginParams{
26 ReturnUrl: returnURL,
27 ErrorCode: errorCode,
28 AddAccount: addAccount,
29 Accounts: registry.Accounts,
30 })
31 case http.MethodPost:
32 handle := r.FormValue("handle")
33 returnURL := r.FormValue("return_url")
34
35 // remove spaces around the handle, handles can't have spaces around them
36 handle = strings.TrimSpace(handle)
37
38 // when users copy their handle from bsky.app, it tends to have these characters around it:
39 //
40 // @nelind.dk:
41 // \u202a ensures that the handle is always rendered left to right and
42 // \u202c reverts that so the rest of the page renders however it should
43 handle = strings.TrimPrefix(handle, "\u202a")
44 handle = strings.TrimSuffix(handle, "\u202c")
45
46 // `@` is harmless
47 handle = strings.TrimPrefix(handle, "@")
48
49 // basic handle validation
50 if !strings.Contains(handle, ".") {
51 l.Error("invalid handle format", "raw", handle)
52 s.pages.Notice(
53 w,
54 "login-msg",
55 fmt.Sprintf("\"%s\" is an invalid handle. Did you mean %s.bsky.social or %s.tngl.sh?", handle, handle, handle),
56 )
57 return
58 }
59
60 ident, err := s.idResolver.ResolveAtIdentifier(r.Context(), handle)
61 if err != nil {
62 l.Warn("handle resolution failed", "handle", handle, "err", err)
63 s.pages.Notice(w, "login-msg", fmt.Sprintf("Could not resolve handle \"%s\". The account may not exist.", handle))
64 return
65 }
66
67 pdsEndpoint := ident.PDSEndpoint()
68 if pdsEndpoint == "" {
69 s.pages.Notice(w, "login-msg", fmt.Sprintf("No PDS found for \"%s\".", handle))
70 return
71 }
72
73 pdsClient := &xrpc.Client{Host: pdsEndpoint, Client: &http.Client{Timeout: 5 * time.Second}}
74 _, err = comatproto.RepoDescribeRepo(r.Context(), pdsClient, ident.DID.String())
75 if err != nil {
76 var xrpcErr *xrpc.Error
77 var xrpcBody *xrpc.XRPCError
78 isDeactivated := errors.As(err, &xrpcErr) &&
79 errors.As(xrpcErr.Wrapped, &xrpcBody) &&
80 xrpcBody.ErrStr == "RepoDeactivated"
81
82 if !isDeactivated {
83 l.Warn("describeRepo failed", "handle", handle, "did", ident.DID, "pds", pdsEndpoint, "err", err)
84 s.pages.Notice(w, "login-msg", fmt.Sprintf("Account \"%s\" is no longer available.", handle))
85 return
86 }
87 }
88
89 if err := s.oauth.SetAuthReturn(w, r, sanitizeReturnURL(returnURL)); err != nil {
90 l.Error("failed to set auth return", "err", err)
91 }
92
93 redirectURL, err := s.oauth.ClientApp.StartAuthFlow(r.Context(), ident.DID.String())
94 if err != nil {
95 l.Error("failed to start auth", "err", err)
96 s.pages.Notice(
97 w,
98 "login-msg",
99 fmt.Sprintf("Failed to start auth flow: %v", err),
100 )
101 return
102 }
103
104 s.pages.HxRedirect(w, redirectURL)
105 }
106}
107
108// sanitizeReturnURL ensures the return URL is a relative path on the same
109// origin. Anything else — absolute URLs, protocol-relative URLs — is replaced
110// with "/" to prevent open redirect after OAuth login.
111func sanitizeReturnURL(s string) string {
112 if strings.HasPrefix(s, "/") && !strings.HasPrefix(s, "//") {
113 return s
114 }
115 return "/"
116}
117
118func (s *State) Logout(w http.ResponseWriter, r *http.Request) {
119 l := s.logger.With("handler", "Logout")
120
121 currentUser := s.oauth.GetMultiAccountUser(r)
122 if currentUser == nil {
123 s.pages.HxRedirect(w, "/login")
124 return
125 }
126
127 currentDid := currentUser.Did
128
129 var remainingAccounts []string
130 for _, acc := range currentUser.Accounts {
131 if acc.Did != currentDid {
132 remainingAccounts = append(remainingAccounts, acc.Did)
133 }
134 }
135
136 if err := s.oauth.RemoveAccount(w, r, currentDid); err != nil {
137 l.Error("failed to remove account from registry", "err", err)
138 }
139
140 if err := s.oauth.DeleteSession(w, r); err != nil {
141 l.Error("failed to delete session", "err", err)
142 }
143
144 if len(remainingAccounts) > 0 {
145 nextDid := remainingAccounts[0]
146 if err := s.oauth.SwitchAccount(w, r, nextDid); err != nil {
147 l.Error("failed to switch to next account", "err", err)
148 s.pages.HxRedirect(w, "/login")
149 return
150 }
151 l.Info("switched to next account after logout", "did", nextDid)
152 s.pages.HxRefresh(w)
153 return
154 }
155
156 l.Info("logged out last account")
157 s.pages.HxRedirect(w, "/login")
158}