commit 61e21e83094506a91cfa745edda606170cb60f08 Author: Unbewohnte Date: Tue May 3 12:34:18 2022 +0300 Initial commit diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..6dd29b7 --- /dev/null +++ b/.gitignore @@ -0,0 +1 @@ +bin/ \ No newline at end of file diff --git a/COPYING b/COPYING new file mode 100644 index 0000000..f288702 --- /dev/null +++ b/COPYING @@ -0,0 +1,674 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. 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If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +. diff --git a/Makefile b/Makefile new file mode 100644 index 0000000..f82ac7e --- /dev/null +++ b/Makefile @@ -0,0 +1,17 @@ +BIN_DIR:=bin +SRC_DIR:=src +EXE_NAME:=gochat +PAGES_DIR:=pages +STATIC_DIR:=static +SCRIPTS_DIR:=scripts + + +all: clean + mkdir $(BIN_DIR) + cd $(SRC_DIR) && go build && mv $(EXE_NAME) ../$(BIN_DIR) + cp -r $(PAGES_DIR) $(BIN_DIR) + cp -r $(STATIC_DIR) $(BIN_DIR) + cp -r $(SCRIPTS_DIR) $(BIN_DIR) + +clean: + rm -rf $(BIN_DIR) \ No newline at end of file diff --git a/README.md b/README.md new file mode 100644 index 0000000..d72e36f --- /dev/null +++ b/README.md @@ -0,0 +1,21 @@ +## gochat +### A dead simple real time webchat with authorization using websockets + +### Building +`make` or `cd src/ && go build && mv gochat ..` + +### Project structure +As you are probably here for reconnaissance reasons for your own project here's a +quick overview of the structure: + +- `pages` -> html pages +- `scripts` -> js files where chat.js is the "heavy-lifter" which actually implements the websocket chat logic +- `static` -> icon, stylesheet for pages +- `src/api` -> the fundament of backend logic, authorization, database and websocket handling,all necessary structs, constants +- `src/log` -> a custom logger +- `src/page` -> a shorcut function for handling html templates +- `src/server` -> the main server struct that glues everything together. For a high-level inspection - refer there +- `src/main.go` -> parse command line flags, set up logging and leave the rest for the server + +### License +GPLv3 \ No newline at end of file diff --git a/pages/base.html b/pages/base.html new file mode 100644 index 0000000..8a1b220 --- /dev/null +++ b/pages/base.html @@ -0,0 +1,50 @@ +{{ define "base" }} + + + + + + + + gochat + + + + + + + + +
+ + +
+ {{ template "content" .}} +
+ +
+
+ + + + + +{{ end }} \ No newline at end of file diff --git a/pages/index.html b/pages/index.html new file mode 100644 index 0000000..b7f994d --- /dev/null +++ b/pages/index.html @@ -0,0 +1,21 @@ +{{ template "base" . }} + +{{ define "content" }} + +

+ logged in as +

+ +

+
+
+ + + +
+ + + + + +{{ end }} \ No newline at end of file diff --git a/pages/login.html b/pages/login.html new file mode 100644 index 0000000..94d6c14 --- /dev/null +++ b/pages/login.html @@ -0,0 +1,26 @@ +{{ template "base" . }} + +{{ define "content" }} + +

Log in

+ +
+

+
+ +

+ +

+
+ +

+ +

+ +

+
+ + + + +{{ end }} \ No newline at end of file diff --git a/pages/register.html b/pages/register.html new file mode 100644 index 0000000..97b5b3b --- /dev/null +++ b/pages/register.html @@ -0,0 +1,26 @@ +{{ template "base" . }} + +{{ define "content" }} + +

Register

+ +
+

+
+ +

+ +

+
+ +

+ +

+ +

+
+ + + + +{{ end }} \ No newline at end of file diff --git a/scripts/chat.js b/scripts/chat.js new file mode 100644 index 0000000..3d51a1d --- /dev/null +++ b/scripts/chat.js @@ -0,0 +1,96 @@ +/* +gochat - A dead simple real time webchat. +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) +This file is a part of gochat +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU 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 General Public License for more details. +You should have received a copy of the GNU General Public License +along with this program. If not, see . +*/ + +let username = localStorage.getItem(LOCALSTORAGE_NAME_KEY); +let secret_hash = localStorage.getItem(LOCALSTORAGE_PASSWORD_HASH_KEY); + +// check whether credentials are right or not +areCredentialsValid({username:username, secret_hash:secret_hash}) +.then(valid => { + if (valid === true) { + // they are valid, connect as a websocket + document.getElementById("logged_username").innerHTML = username; + let socket = new WebSocket(`ws://${BACKEND_URL}/${API_WEBSOCKET_ENDPOINT}`); + + // send auth data right away, as API tells us to do + socket.onopen = event => { + console.log("Connected to the server"); + let auth_data = JSON.stringify({ + username: username, + secret_hash: secret_hash, + }); + socket.send(auth_data); + } + + socket.onclose = event => { + console.log("Closed connection: ", event); + socket.close(); + + let chatbox = document.getElementById("chatbox"); + chatbox.innerHTML += "Connection closed"; + chatbox.scrollTop = chatbox.scrollHeight; + }; + + // display it + socket.onmessage = event => { + let message = JSON.parse(event.data); + let from_user = message.from.username; + + let constructed_message_to_display = `${from_user}: ${message.contents}` + "\n"; + + let chatbox = document.getElementById("chatbox"); + chatbox.innerHTML += constructed_message_to_display; + chatbox.scrollTop = chatbox.scrollHeight; + } + + // make buttons do intended + let send_button = document.getElementById("send_button"); + send_button.addEventListener("click", (event) => { + let text_input = document.getElementById("text_input"); + + socket.send( + JSON.stringify({ + contents: String(text_input.value), + })); + + text_input.value = ""; + text_input.focus(); + }); + + let disconnect_button = document.getElementById("disconnect_button"); + disconnect_button.addEventListener("click", (event) => { + socket.close(); + disconnect_button.value = "Reconnect"; + disconnect_button.addEventListener("click", (event) => { + location.reload(); + }) + }) + + // make message to be sent via pressing 'Enter' key + document.addEventListener("keypress", (event) => { + if (event.key == "Enter") { + send_button.click(); + } + }) + + // and focus the text input so the user does not have to click it manually + document.getElementById("text_input").focus(); + + } else { + // credentials are not valid ! To the registration page you go + window.location.replace("/register"); + } +}) \ No newline at end of file diff --git a/scripts/constants.js b/scripts/constants.js new file mode 100644 index 0000000..3a2b25e --- /dev/null +++ b/scripts/constants.js @@ -0,0 +1,27 @@ +/* +gochat - A dead simple real time webchat. +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) +This file is a part of gochat +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU 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 General Public License for more details. +You should have received a copy of the GNU General Public License +along with this program. If not, see . +*/ + +const API_BASE_ENDPOINT = "api"; +const API_USER_ENDPOINT = "api/user" +const API_WEBSOCKET_ENDPOINT = "api/ws"; + +const AUTH_HEADER_KEY = "AUTH_INFO"; +const AUTH_SEPARATOR = ":" + +const LOCALSTORAGE_NAME_KEY = "username"; +const LOCALSTORAGE_PASSWORD_HASH_KEY = "secret_hash"; + +const BACKEND_URL = window.location.host; \ No newline at end of file diff --git a/scripts/sha256.js b/scripts/sha256.js new file mode 100644 index 0000000..1c57190 --- /dev/null +++ b/scripts/sha256.js @@ -0,0 +1,26 @@ +/* +gochat - A dead simple real time webchat. +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) +This file is a part of gochat +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU 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 General Public License for more details. +You should have received a copy of the GNU General Public License +along with this program. If not, see . +*/ + +function sha256(string) { + const encoded_string = new TextEncoder().encode(string); + return crypto.subtle.digest('SHA-256', encoded_string).then((hash_sum) => { + const hashArray = Array.from(new Uint8Array(hash_sum)); + const hashHex = hashArray + .map((bytes) => bytes.toString(16).padStart(2, '0')) + .join(''); + return hashHex; + }); + } \ No newline at end of file diff --git a/scripts/to_hex_string.js b/scripts/to_hex_string.js new file mode 100644 index 0000000..f1e4056 --- /dev/null +++ b/scripts/to_hex_string.js @@ -0,0 +1,22 @@ +/* +gochat - A dead simple real time webchat. +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) +This file is a part of gochat +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU 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 General Public License for more details. +You should have received a copy of the GNU General Public License +along with this program. If not, see . +*/ + + +function to_hex_string(byteArr) { + return Array.from(byteArr, function(byte) { + return ('0' + (byte & 0xFF).toString(16).slice(-2)); + }).join('') +} \ No newline at end of file diff --git a/scripts/user.js b/scripts/user.js new file mode 100644 index 0000000..5cadc4f --- /dev/null +++ b/scripts/user.js @@ -0,0 +1,112 @@ +/* +gochat - A dead simple real time webchat. +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) +This file is a part of gochat +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU 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 General Public License for more details. +You should have received a copy of the GNU General Public License +along with this program. If not, see . +*/ + + +async function register() { + let auth_form = document.forms["auth_form"]; + + let username = String(auth_form.elements["username"].value).trim(); + if (username.length < 3) { + document.getElementById("error_output").innerHTML = "Username must be >= 3 characters long"; + return; + } + + let password = String(auth_form.elements["password"].value).trim(); + if (password.length < 3) { + document.getElementById("error_output").innerHTML = "Password must be >= 3 characters long"; + return; + } + + sha256(password).then((password_sha256) => { + let post_data = { + username: username, + secret_hash: password_sha256, + }; + + fetch(API_USER_ENDPOINT, { + method: "POST", + headers: {"Content-Type": "application/json"}, + body: JSON.stringify(post_data), + }) + .then(response => { + if (response.status == 200) { + localStorage.setItem(LOCALSTORAGE_NAME_KEY, username); + localStorage.setItem(LOCALSTORAGE_PASSWORD_HASH_KEY, password_sha256); + window.location.replace("/") + } + }) + .catch((error) => { + document.getElementById("error_output").innerHTML = error; + }); + }); +}; + +async function areCredentialsValid(user_credentials) { + let valid = false; + + await fetch(API_USER_ENDPOINT, { + method: "GET", + headers: {"AUTH_INFO": user_credentials.username+":"+user_credentials.secret_hash}, + }) + .then(response => { + return response.text(); + }) + .then(response_data => { + let response = JSON.parse(response_data) + console.log(response); + if (response.valid === true) { + valid = true; + } else { + valid = false; + } + }); + + return valid; +} + +async function login() { + let auth_form = document.forms["auth_form"]; + + let username = String(auth_form.elements["username"].value).trim(); + if (username.length < 3) { + document.getElementById("error_output").innerHTML = "Username must be >= 3 characters long"; + return; + } + + let password = String(auth_form.elements["password"].value).trim(); + if (password.length < 3) { + document.getElementById("error_output").innerHTML = "Password must be >= 3 characters long"; + return; + } + + await sha256(password).then((password_sha256) => { + let user_credentials = { + "username": username, + "secret_hash": password_sha256, + }; + + areCredentialsValid(user_credentials) + .then(valid => { + if (valid === true) { + localStorage.setItem(LOCALSTORAGE_NAME_KEY, username); + localStorage.setItem(LOCALSTORAGE_PASSWORD_HASH_KEY, password_sha256); + window.location.replace("/"); + } else { + document.getElementById("error_output").innerHTML = "Invalid credentials"; + } + }) + }); +} \ No newline at end of file diff --git a/src/api/auth.go b/src/api/auth.go new file mode 100644 index 0000000..301cdca --- /dev/null +++ b/src/api/auth.go @@ -0,0 +1,81 @@ +/* +gochat - A dead simple real time webchat. +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) +This file is a part of gochat +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU 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 General Public License for more details. +You should have received a copy of the GNU General Public License +along with this program. If not, see . +*/ + +package api + +import ( + "fmt" + "net/http" + "strings" +) + +const ( + AuthHeaderKey string = "AUTH_INFO" + AuthSeparator string = ":" +) + +var ErrNotAuthorized error = fmt.Errorf("not authorized") + +// Extract information about the sender from request headers. +// If no data is given or just wrong - returns a default user struct +func GetUserAuthHeaderData(req *http.Request) User { + authData := req.Header.Get(AuthHeaderKey) + dividedAuthData := strings.Split(authData, AuthSeparator) + if len(dividedAuthData) != 2 { + return User{} + } + username, passHash := dividedAuthData[0], dividedAuthData[1] + + return User{ + Name: username, + SecretHash: passHash, + } +} + +// Checks whether provided request indeed contains SOME authentication information. +// Does not check it for being legitimate or not +func WithAuth(req *http.Request) bool { + authenticationData := req.Header.Get(AuthHeaderKey) + if authenticationData == "" || len(authenticationData) < 3 { + return false + } + + return true +} + +// Checks whether request contains valid and real user authorization data that is in the database +func (db *DB) IsValidAuth(req *http.Request) bool { + if !WithAuth(req) { + return false + } + + headerUser := GetUserAuthHeaderData(req) + + if !db.DoesUserExist(headerUser.Name) { + return false + } + + userDB, err := db.GetUser(headerUser.Name) + if err != nil { + return false + } + + if userDB.SecretHash != headerUser.SecretHash { + return false + } + + return true +} diff --git a/src/api/db.go b/src/api/db.go new file mode 100644 index 0000000..0cac241 --- /dev/null +++ b/src/api/db.go @@ -0,0 +1,114 @@ +/* +gochat - A dead simple real time webchat. +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) +This file is a part of gochat +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU 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 General Public License for more details. +You should have received a copy of the GNU General Public License +along with this program. If not, see . +*/ + +package api + +import ( + "database/sql" + "fmt" + "os" + + _ "github.com/mattn/go-sqlite3" +) + +const ( + UsersTablename string = "users" + // MessagesTablename string = "messages" +) + +// SQL database wrapper +type DB struct { + *sql.DB +} + +// Closes database connection +func (db *DB) ShutDown() { + db.Close() +} + +func (db *DB) createUsersTable() error { + command := fmt.Sprintf( + `CREATE TABLE IF NOT EXISTS %s + (username TEXT NOT NULL PRIMARY KEY, secret_hash TEXT NOT NULL)`, UsersTablename) + _, err := db.Exec(command) + if err != nil { + return err + } + + return nil +} + +// func (db *DB) createMessagesTable() error { +// command := fmt.Sprintf( +// `CREATE TABLE IF NOT EXISTS %s +// (id INTEGER NOT NULL PRIMARY KEY, content TEXT NOT NULL, +// from_name TEXT NOT NULL, FOREIGN KEY(from_name) REFERENCES %s(username))`, +// MessagesTablename, UsersTablename, +// ) + +// _, err := db.Exec(command) +// if err != nil { +// return err +// } + +// return nil +// } + +func (db *DB) setUpTables() error { + err := db.createUsersTable() + if err != nil { + return fmt.Errorf("error creating users table: %s", err) + } + + return nil +} + +// Creates a database if does not exist +func CreateDB(path string) error { + dbFile, err := os.OpenFile(path, os.O_CREATE|os.O_RDWR, os.ModePerm) + if err != nil { + return err + } + dbFile.Close() + + sqlDB, err := sql.Open("sqlite3", path) + if err != nil { + return err + } + db := DB{ + sqlDB, + } + + err = db.setUpTables() + if err != nil { + return fmt.Errorf("could not set up tables: %s", err) + } + + return nil +} + +// Opens a DB +func OpenDB(path string) (*DB, error) { + sqlDB, err := sql.Open("sqlite3", path) + if err != nil { + return nil, err + } + db := DB{ + sqlDB, + } + + return &db, nil +} diff --git a/src/api/message.go b/src/api/message.go new file mode 100644 index 0000000..d3df6ce --- /dev/null +++ b/src/api/message.go @@ -0,0 +1,58 @@ +/* +gochat - A dead simple real time webchat. +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) +This file is a part of gochat +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU 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 General Public License for more details. +You should have received a copy of the GNU General Public License +along with this program. If not, see . +*/ + +package api + +// A message struct that is converted back and forth to JSON in order to communicate with frontend +type Message struct { + TimeStamp uint64 `json:"timestamp"` + From User `json:"from"` + Contents string `json:"contents"` +} + +/* PROBABLY come back later and implement a message-remembering feature */ + +// func (db *DB) AddMessage(message Message) error { +// command := fmt.Sprintf("INSERT INTO %s(from, contents) VALUES(%s, %s)", MessagesTablename, message.From.Name, message.Contents) +// _, err := db.Exec(command) +// if err != nil { +// return err +// } + +// return nil +// } + +// func (db *DB) GetAllMessages() (*[]Message, error) { +// command := fmt.Sprintf("SELECT * FROM %s", MessagesTablename) +// rows, err := db.Query(command) +// if err != nil { +// return nil, err +// } + +// var messages []Message + +// /* +// (id INTEGER NOT NULL PRIMARY KEY, content TEXT NOT NULL, +// to_name TEXT NOT NULL, from_name TEXT NOT NULL, FOREIGN KEY(from_name, to_name) REFERENCES %s(username, username))`, +// */ +// for rows.Next() { +// var message Message +// rows.Scan(&message.ID, &message.Contents, message.From.Name) +// messages = append(messages, message) +// } + +// return &messages, nil +// } diff --git a/src/api/routes.go b/src/api/routes.go new file mode 100644 index 0000000..728edb2 --- /dev/null +++ b/src/api/routes.go @@ -0,0 +1,24 @@ +/* +gochat - A dead simple real time webchat. +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) +This file is a part of gochat +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU 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 General Public License for more details. +You should have received a copy of the GNU General Public License +along with this program. If not, see . +*/ + +package api + +const ( + RouteBase string = "/api" + RouteUsers string = RouteBase + "/user" + RouteWebsockets string = RouteBase + "/ws" + RouteRooms string = RouteBase + "/room" +) diff --git a/src/api/user.go b/src/api/user.go new file mode 100644 index 0000000..fff6329 --- /dev/null +++ b/src/api/user.go @@ -0,0 +1,102 @@ +/* +gochat - A dead simple real time webchat. +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) +This file is a part of gochat +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU 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 General Public License for more details. +You should have received a copy of the GNU General Public License +along with this program. If not, see . +*/ + +package api + +import ( + "fmt" + + "unbewohnte.xyz/gochat/log" +) + +const HashLength uint = 64 + +type User struct { + Name string `json:"username"` + SecretHash string `json:"secret_hash"` + Created uint64 +} + +// Used to declare connection/disconnection messages in chat +var UserSystem User = User{ + Name: "System", + SecretHash: "_", + Created: 0, +} + +// Get existing user from database by unique name +func (db *DB) GetUser(name string) (User, error) { + command := fmt.Sprintf("SELECT * FROM %s WHERE username=\"%s\"", UsersTablename, name) + result := db.QueryRow(command) + err := result.Err() + if err != nil { + return User{}, err + } + + user := User{} + err = result.Scan(&user.Name, &user.SecretHash) + if err != nil { + return User{}, err + } + + return user, nil +} + +// Create a new user with a unique name +func (db *DB) CreateUser(user *User) error { + command := fmt.Sprintf("INSERT INTO %s (username, secret_hash) VALUES (?, ?)", UsersTablename) + _, err := db.Exec(command, user.Name, user.SecretHash) + if err != nil { + return err + } + + log.Info("created user \"%s\"", user.Name) + + return nil +} + +// Tells if the user already exists in the db +func (db *DB) DoesUserExist(name string) bool { + _, err := db.GetUser(name) + if err != nil { + return false + } + + return true +} + +// func (db *DB) GetAllUsers() (*[]User, error) { +// command := fmt.Sprintf("SELECT * FROM %s", UsersTablename) +// rows, err := db.Query(command) +// if err != nil { +// return nil, err +// } + +// var users []User + +// for rows.Next() { +// var user User +// rows.Scan(&user.Name, &user.SecretHash) +// users = append(users, user) +// } + +// return &users, nil +// } + +// Used to send validation check results for user credentials to frontend +type UserCredentialsValidation struct { + Valid bool `json:"valid"` +} diff --git a/src/api/websocket.go b/src/api/websocket.go new file mode 100644 index 0000000..b9bb630 --- /dev/null +++ b/src/api/websocket.go @@ -0,0 +1,107 @@ +/* +gochat - A dead simple real time webchat. +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) +This file is a part of gochat +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU 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 General Public License for more details. +You should have received a copy of the GNU General Public License +along with this program. If not, see . +*/ + +package api + +import ( + "encoding/json" + "fmt" + "time" + + "github.com/gorilla/websocket" + "unbewohnte.xyz/gochat/log" +) + +// Websocket connection paired with the owner +type WS struct { + Socket *websocket.Conn + User User +} + +// All existing websockets wrapper +type WSHolder struct { + Sockets []*WS +} + +// Untrack user's websocket from broadcast +func (holder *WSHolder) Remove(username string) { + var indexToRemove int + for index, socket := range holder.Sockets { + if socket.User.Name == username { + indexToRemove = index + break + } + } + + if len(holder.Sockets) >= 2 { + holder.Sockets = append(holder.Sockets[:indexToRemove], holder.Sockets[indexToRemove+1:]...) + } else { + holder.Sockets = append(holder.Sockets[:indexToRemove]) + } +} + +// Tell the websocket that it is no longer connected +func Disconnect(ws *websocket.Conn) { + ws.WriteControl(websocket.CloseMessage, nil, time.Now().Add(time.Second*1)) + ws.Close() +} + +// Handle all incoming messages from this websocket, redirecting messages to specified output +func (holder *WSHolder) HandleNewWebSocketMessages(ws *WS, output chan Message) { + for { + msgType, contents, err := ws.Socket.ReadMessage() + if err != nil { + log.Error("could not read message from websocket: %s", err) + Disconnect(ws.Socket) + holder.Remove(ws.User.Name) + + disconnectionMessage := Message{ + From: UserSystem, + Contents: fmt.Sprintf("%s has disconnected", ws.User.Name), + } + output <- disconnectionMessage + break + } + + switch msgType { + case websocket.CloseMessage: + ws.Socket.Close() + holder.Remove(ws.User.Name) + + disconnectionMessage := Message{ + From: UserSystem, + Contents: fmt.Sprintf("%s has disconnected", ws.User.Name), + } + output <- disconnectionMessage + + case websocket.TextMessage: + var newMessage Message + err = json.Unmarshal(contents, &newMessage) + if err != nil { + log.Error("error unmarshaling text message from \"%s\"'s websocket: %s", ws.User.Name, err) + break + } + + if len(newMessage.Contents) < 1 { + break + } + + newMessage.From = ws.User + output <- newMessage + } + + } +} diff --git a/src/go.mod b/src/go.mod new file mode 100644 index 0000000..7ceeb25 --- /dev/null +++ b/src/go.mod @@ -0,0 +1,8 @@ +module unbewohnte.xyz/gochat + +go 1.17 + +require ( + github.com/gorilla/websocket v1.5.0 // indirect + github.com/mattn/go-sqlite3 v1.14.12 // indirect +) diff --git a/src/go.sum b/src/go.sum new file mode 100644 index 0000000..62353e9 --- /dev/null +++ b/src/go.sum @@ -0,0 +1,4 @@ +github.com/gorilla/websocket v1.5.0 h1:PPwGk2jz7EePpoHN/+ClbZu8SPxiqlu12wZP/3sWmnc= +github.com/gorilla/websocket v1.5.0/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE= +github.com/mattn/go-sqlite3 v1.14.12 h1:TJ1bhYJPV44phC+IMu1u2K/i5RriLTPe+yc68XDJ1Z0= +github.com/mattn/go-sqlite3 v1.14.12/go.mod h1:NyWgC/yNuGj7Q9rpYnZvas74GogHl5/Z4A/KQRfk6bU= diff --git a/src/log/log.go b/src/log/log.go new file mode 100644 index 0000000..fa96419 --- /dev/null +++ b/src/log/log.go @@ -0,0 +1,55 @@ +/* +gochat - A dead simple real time webchat. +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) +This file is a part of gochat +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU 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 General Public License for more details. +You should have received a copy of the GNU General Public License +along with this program. If not, see . +*/ + +package log + +import ( + "io" + "log" + "os" +) + +// 3 basic loggers in global space +var ( + infoLog *log.Logger + warningLog *log.Logger + errorLog *log.Logger +) + +func init() { + infoLog = log.New(os.Stdout, "[INFO] ", log.Ldate|log.Ltime) + warningLog = log.New(os.Stdout, "[WARNING] ", log.Ldate|log.Ltime) + errorLog = log.New(os.Stdout, "[ERROR] ", log.Ldate|log.Ltime|log.Lshortfile) +} + +// Set up loggers to write to the given writer +func SetOutput(writer io.Writer) { + infoLog.SetOutput(writer) + warningLog.SetOutput(writer) + errorLog.SetOutput(writer) +} + +func Info(format string, a ...interface{}) { + infoLog.Printf(format, a...) +} + +func Warning(format string, a ...interface{}) { + warningLog.Printf(format, a...) +} + +func Error(format string, a ...interface{}) { + errorLog.Printf(format, a...) +} diff --git a/src/main.go b/src/main.go new file mode 100644 index 0000000..59f98be --- /dev/null +++ b/src/main.go @@ -0,0 +1,74 @@ +/* +gochat - A dead simple real time webchat. +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) +This file is a part of gochat +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU 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 General Public License for more details. +You should have received a copy of the GNU General Public License +along with this program. If not, see . +*/ + +package main + +import ( + "flag" + "fmt" + "io" + "os" + "path/filepath" + + "unbewohnte.xyz/gochat/log" + "unbewohnte.xyz/gochat/server" +) + +const version string = "0.1.0" + +func main() { + // set up logging + exePath, err := os.Executable() + if err != nil { + log.Error("could not lookup executable's path: %s", err) + } + + exeDirPath := filepath.Dir(exePath) + logsDirPath := filepath.Join(exeDirPath, "logs") + + err = os.MkdirAll(logsDirPath, os.ModePerm) + if err != nil { + log.Error("could not create logs directory: %s", err) + } + + logsFile, err := os.Create(filepath.Join(logsDirPath, "latest.log")) + if err != nil { + log.Error("could not create logs file: %s", err) + } + + if err == nil { + log.SetOutput(io.MultiWriter(os.Stdout, logsFile)) + } else { + log.SetOutput(os.Stdout) + } + + // work out launch flags + var port uint + flag.UintVar(&port, "port", 8080, "Set working port") + flag.Usage = func() { + fmt.Printf("gochat v%s\n\nFlags\nport [uint] -> specify a port number (default: 8080)\n\n(c) Unbewohnte (Kasyanov Nikolay Alexeyevich)\n", version) + } + flag.Parse() + + const dbFilename string = "gochat.db" + dbPath := filepath.Join(exeDirPath, dbFilename) + + server, err := server.New(exeDirPath, dbPath, port) + if err != nil { + log.Error("could not create a new server instance: %s", err) + } + server.Start() +} diff --git a/src/page/page.go b/src/page/page.go new file mode 100644 index 0000000..1a45d8f --- /dev/null +++ b/src/page/page.go @@ -0,0 +1,32 @@ +/* +gochat - A dead simple real time webchat. +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) +This file is a part of gochat +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU 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 General Public License for more details. +You should have received a copy of the GNU General Public License +along with this program. If not, see . +*/ + +package page + +import ( + "html/template" + "path/filepath" +) + +// Parse files in pagesDir and return a ready-to-render template +func Get(pagesDir string, base string, pagename string) (*template.Template, error) { + page, err := template.ParseFiles(filepath.Join(pagesDir, base), filepath.Join(pagesDir, pagename)) + if err != nil { + return nil, err + } + + return page, nil +} diff --git a/src/server/server.go b/src/server/server.go new file mode 100644 index 0000000..e3f5d39 --- /dev/null +++ b/src/server/server.go @@ -0,0 +1,126 @@ +/* +gochat - A dead simple real time webchat. +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) +This file is a part of gochat +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU 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 General Public License for more details. +You should have received a copy of the GNU General Public License +along with this program. If not, see . +*/ + +package server + +import ( + "fmt" + "net/http" + "os" + "path/filepath" + "strings" + "time" + + "unbewohnte.xyz/gochat/api" + "unbewohnte.xyz/gochat/log" + "unbewohnte.xyz/gochat/page" +) + +// Server structure that glues api logic and http/websocket server together +type Server struct { + workingDir string + http *http.Server + db *api.DB + websockets *api.WSHolder + incomingMessages chan api.Message +} + +// Create a new configured and ready-to-launch server +func New(workingDir string, dbPath string, port uint) (*Server, error) { + var server = Server{ + workingDir: workingDir, + websockets: &api.WSHolder{}, + incomingMessages: make(chan api.Message), + } + + err := api.CreateDB(dbPath) + if err != nil { + log.Error("could not create database: %s", err) + os.Exit(1) + } + + db, err := api.OpenDB(dbPath) + if err != nil { + log.Error("could not open database: %s", err) + os.Exit(1) + } + server.db = db + + // set up routes and handlers + const ( + pagesDirName string = "pages" + staticDirName string = "static" + scriptsDirName string = "scripts" + ) + + pagesDirPath := filepath.Join(workingDir, pagesDirName) + + serveMux := http.NewServeMux() + + serveMux.Handle("/static/", http.StripPrefix("/static/", http.FileServer(http.Dir(filepath.Join(workingDir, staticDirName))))) + serveMux.Handle("/scripts/", http.StripPrefix("/scripts/", http.FileServer(http.Dir(filepath.Join(workingDir, scriptsDirName))))) + + serveMux.HandleFunc("/", func(w http.ResponseWriter, req *http.Request) { + switch req.URL.Path { + case "/": + requestedPage, err := page.Get(pagesDirPath, "base.html", "index.html") + if err != nil { + log.Error("error getting page on route %s: %s", req.URL.Path, err) + http.Error(w, "internal server error", http.StatusInternalServerError) + } + requestedPage.ExecuteTemplate(w, "index.html", nil) + + default: + if strings.HasPrefix(req.URL.Path, api.RouteBase) { + return + } + + requestedPage, err := page.Get(pagesDirPath, "base.html", req.URL.Path[1:]+".html") + if err != nil { + log.Error("error getting page on route %s: %s", req.URL.Path, err) + http.Error(w, "internal server error", http.StatusInternalServerError) + } + requestedPage.ExecuteTemplate(w, req.URL.Path[1:]+".html", nil) + } + }) + + // user api endpoint + serveMux.HandleFunc(api.RouteUsers, server.HandlerUsers) + // ws api endpoint + serveMux.HandleFunc(api.RouteWebsockets, server.HandlerWebsockets) + + httpServer := http.Server{ + Addr: fmt.Sprintf(":%d", port), + Handler: serveMux, + ReadTimeout: time.Second * 5, + WriteTimeout: time.Second * 5, + } + server.http = &httpServer + + return &server, nil +} + +// Fire up the server +func (s *Server) Start() { + defer s.db.ShutDown() + go s.BroadcastMessages() + + // fire up a server + err := s.http.ListenAndServe() + if err != nil { + log.Error("FATAL server error: %s", err) + } +} diff --git a/src/server/userHandler.go b/src/server/userHandler.go new file mode 100644 index 0000000..a8b2dd1 --- /dev/null +++ b/src/server/userHandler.go @@ -0,0 +1,128 @@ +/* +gochat - A dead simple real time webchat. +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) +This file is a part of gochat +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU 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 General Public License for more details. +You should have received a copy of the GNU General Public License +along with this program. If not, see . +*/ + +package server + +import ( + "encoding/json" + "io" + "net/http" + + "unbewohnte.xyz/gochat/api" + "unbewohnte.xyz/gochat/log" +) + +// User creation/credentials validation http handler +func (s *Server) HandlerUsers(w http.ResponseWriter, req *http.Request) { + switch req.Method { + case http.MethodPost: + // unmarshal incoming json + requestBody, err := io.ReadAll(req.Body) + if err != nil { + http.Error(w, "", http.StatusInternalServerError) + return + } + + var newUser api.User + err = json.Unmarshal(requestBody, &newUser) + if err != nil { + log.Error("could not unmarshal new user json: %s", err) + http.Error(w, "invalid user json", http.StatusBadRequest) + return + } + + // check if this all is genuine + if len(newUser.Name) <= 1 || uint(len(newUser.SecretHash)) != api.HashLength { + log.Error("could not create a new user: incoming name or secret hash is invalid") + http.Error(w, "invalid user json", http.StatusBadRequest) + return + } + + if s.db.DoesUserExist(newUser.Name) { + // already have ! + http.Error(w, "already exists", http.StatusBadRequest) + return + } + + // add user to db + err = s.db.CreateUser(&newUser) + if err != nil { + http.Error(w, "", http.StatusInternalServerError) + log.Error("could not create a new user \"%s\": %s", newUser.Name, err) + return + } + + log.Info("successfully created a new user: \"%s\"", newUser.Name) + + w.WriteHeader(http.StatusOK) + + case http.MethodGet: + // TODO(redo to make it return true or false whether user credentials are okay or not) + headerUserData := api.GetUserAuthHeaderData(req) + + if s.db.DoesUserExist(headerUserData.Name) { + response := api.UserCredentialsValidation{} + + userDB, _ := s.db.GetUser(headerUserData.Name) + + if userDB.SecretHash != headerUserData.SecretHash { + // passwords do not match + response.Valid = false + } else { + response.Valid = true + } + + responseBytes, err := json.Marshal(&response) + if err != nil { + log.Error("could not marshal user credentials validation response: %s", err) + http.Error(w, "", http.StatusInternalServerError) + return + } + + w.Write(responseBytes) + + } else { + // does not even exist + responseBytes, err := json.Marshal(&api.UserCredentialsValidation{ + Valid: false, + }) + if err != nil { + log.Error("could not marshal user credentials validation response: %s", err) + http.Error(w, "", http.StatusInternalServerError) + return + } + + w.Write(responseBytes) + } + + // users, err := db.getAllUsers() + // if err != nil { + // http.Error(w, "", http.StatusInternalServerError) + // return + // } + + // w.Header().Add("Content-type", "application/json") + // userBytes, err := json.Marshal(*users) + // if err != nil { + // break + // } + + // w.Write(userBytes) + + default: + http.Error(w, "wrong method", http.StatusMethodNotAllowed) + } +} diff --git a/src/server/websocketHandler.go b/src/server/websocketHandler.go new file mode 100644 index 0000000..909905f --- /dev/null +++ b/src/server/websocketHandler.go @@ -0,0 +1,89 @@ +/* +gochat - A dead simple real time webchat. +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) +This file is a part of gochat +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU 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 General Public License for more details. +You should have received a copy of the GNU General Public License +along with this program. If not, see . +*/ + +package server + +import ( + "fmt" + "net/http" + + "github.com/gorilla/websocket" + "unbewohnte.xyz/gochat/api" + "unbewohnte.xyz/gochat/log" +) + +// Websocket creation handler +func (s *Server) HandlerWebsockets(w http.ResponseWriter, req *http.Request) { + upgrader := websocket.Upgrader{} + socket, err := upgrader.Upgrade(w, req, nil) + if err != nil { + http.Error(w, "could not upgrade to a websocket", http.StatusInternalServerError) + return + } + + var authInfo api.User + err = socket.ReadJSON(&authInfo) + if err != nil { + log.Error("%s did not send auth info on websocket connection at all: %s", socket.RemoteAddr(), err) + api.Disconnect(socket) + return + } + + if !s.db.DoesUserExist(authInfo.Name) { + log.Error("%s sent an invalid authentication data on websocket: user does not exist", socket.RemoteAddr()) + api.Disconnect(socket) + return + } + + userDB, _ := s.db.GetUser(authInfo.Name) + + if authInfo.SecretHash != userDB.SecretHash { + log.Error("%s did not send valid password hash on websocket", socket.RemoteAddr()) + api.Disconnect(socket) + return + } + + newWS := api.WS{ + Socket: socket, + User: authInfo, + } + + // add this new authorized socket to the broadcast + s.websockets.Sockets = append(s.websockets.Sockets, &newWS) + + log.Info("A new websocket connection has been established with %s as \"%s\"", newWS.Socket.RemoteAddr(), newWS.User.Name) + go s.websockets.HandleNewWebSocketMessages(&newWS, s.incomingMessages) + + newConnectionMessage := api.Message{ + From: api.UserSystem, + Contents: fmt.Sprintf("%s has connected", newWS.User.Name), + } + s.incomingMessages <- newConnectionMessage +} + +// Send incoming messages from each websocket to all connected ones +func (s *Server) BroadcastMessages() { + for { + message, ok := <-s.incomingMessages + if !ok { + break + } + + for _, ws := range s.websockets.Sockets { + ws.Socket.WriteJSON(&message) + } + } +} diff --git a/static/images/favicon.png b/static/images/favicon.png new file mode 100755 index 0000000..b01ad8a Binary files /dev/null and b/static/images/favicon.png differ diff --git a/static/style.css b/static/style.css new file mode 100644 index 0000000..fd684f9 --- /dev/null +++ b/static/style.css @@ -0,0 +1,57 @@ +@viewport { + width: device-width; + zoom: 1.0; +} + +body { + margin: auto; + margin-top: 5ch; + margin-bottom: 10ch; + background-color: #232729; + max-width: 120ch; + padding-left: 2ch; + padding-right: 2ch; + + + font-size: 1.1em; + + word-wrap: break-word; + color: #bbbbbb; +} + +a { + text-decoration: none; + color: #bbbbbb; +} + +a:hover { + color: azure; +} + +nav { + white-space: nowrap; + display: inline-block; +} + +#wrapper { + display: flex; + flex-flow: column wrap; + justify-content: center; + row-gap: 3ch; +} + +#chatbox { + flex: 1 0 90%; + width: auto; + height: 60ch; + + max-width: 80ch; + max-height: 150ch; + + overflow-y: scroll; + border: 1px solid #bbbbbb; +} + +#error_output { + color: firebrick; +} \ No newline at end of file