diff options
Diffstat (limited to 'endpoint_ws.go')
-rw-r--r-- | endpoint_ws.go | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/endpoint_ws.go b/endpoint_ws.go new file mode 100644 index 0000000..2ea0a2a --- /dev/null +++ b/endpoint_ws.go @@ -0,0 +1,171 @@ +/* + * WebSocket endpoint handler + * + * Copyright (C) 2024 Runxi Yu <https://runxiyu.org> + * SPDX-License-Identifier: AGPL-3.0-or-later + * + * 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 <https://www.gnu.org/licenses/>. + */ + +package main + +import ( + "errors" + "log" + "net/http" + "time" + + "github.com/coder/websocket" + "github.com/google/uuid" + "github.com/jackc/pgx/v5" +) + +/* + * Handle requests to the WebSocket endpoint and establish a connection. + * Authentication is handled here, but afterwards, the connection is really + * handled in handleConn. + */ +func handleWs(w http.ResponseWriter, req *http.Request) { + wsOptions := &websocket.AcceptOptions{ + Subprotocols: []string{"cca1"}, + } //exhaustruct:ignore + c, err := websocket.Accept( + w, + req, + wsOptions, + ) + if err != nil { + wstr( + w, + http.StatusBadRequest, + "This endpoint only supports valid WebSocket connections.", + ) + return + } + defer func() { + _ = c.CloseNow() + }() + + fake := false + + sessionCookie, err := req.Cookie("session") + if errors.Is(err, http.ErrNoCookie) { + if config.Auth.Fake == 0 { + err := writeText(req.Context(), c, "U") + if err != nil { + log.Println(err) + } + return + } + fake = true + } else if err != nil { + err := writeText(req.Context(), c, "E :Error fetching cookie") + if err != nil { + log.Println(err) + } + return + } + + var userID string + var session string + var expr int + + if fake { + switch config.Auth.Fake { + case 9080: + _uuid, err := uuid.NewRandom() + if err != nil { + log.Println(err) + return + } + userID = _uuid.String() + case 4712: + userID = "fake" + default: + panic("not supposed to happen") + } + session, err = randomString(20) + if err != nil { + log.Println(err) + return + } + _, err = db.Exec( + req.Context(), + "INSERT INTO users (id, name, email, department, session, expr) VALUES ($1, $2, $3, $4, $5, $6)", + userID, + "Fake User", + "fake@runxiyu.org", + "Y11", + session, + time.Now().Add( + time.Duration(config.Auth.Expr)*time.Second, + ).Unix(), + ) + if err != nil && config.Auth.Fake != 4712 { + err := writeText( + req.Context(), + c, + "E :Database error while writing fake account info", + ) + if err != nil { + log.Println(err) + } + return + } + err = writeText(req.Context(), c, "FAKE "+userID+" "+session) + if err != nil { + log.Println(err) + return + } + } else { + session = sessionCookie.Value + err = db.QueryRow( + req.Context(), + "SELECT id, expr FROM users WHERE session = $1", + session, + ).Scan(&userID, &expr) + if errors.Is(err, pgx.ErrNoRows) { + err := writeText(req.Context(), c, "U") + if err != nil { + log.Println(err) + } + return + } else if err != nil { + err := writeText( + req.Context(), + c, + "E :Database error while selecting session", + ) + if err != nil { + log.Println(err) + } + return + } + } + + /* + * Now that we have an authenticated request, this WebSocket connection + * may be simply associated with the session and userID. + */ + err = handleConn( + req.Context(), + c, + session, + userID, + ) + if err != nil { + log.Printf("%v", err) + return + } +} |