Files
pastebin/yasuc.go

585 lines
16 KiB
Go

// yasuc - yet another sprunge.us clone (command line pastebin)
//
// Copyright (C) Tom Jakubowski <tom@crystae.net>
//
// 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 <http://www.gnu.org/licenses/>.
package main
import (
"crypto/sha256"
"database/sql"
"encoding/hex"
"flag"
"fmt"
"html/template"
"log"
"math/rand"
"net/http"
"os"
"strings"
"time"
_ "modernc.org/sqlite"
)
const (
maxPasteSize = 4 * 1024 * 1024
shortIDLength = 7
)
const usageText = `
<!doctype html>
<html>
<head>
</head>
<body>
<pre>
yasuc(1) YASUC yasuc(1)
NAME
yasuc - command line pastebin.
SYNOPSIS
&lt;command&gt; | curl -F 'sprunge=&lt;-' {{.BaseURL}}
DESCRIPTION
A command line pastebin. Pastes are immutable and created with simple HTTP
POST requests. The path of a paste's URL is a short unique identifier.
EXAMPLE
$ echo 'hello world' | curl -F 'sprunge=&lt;-' {{.BaseURL}}
{{.BaseURL}}/Ly34kx3
$ firefox {{.BaseURL}}/Ly34kx3
COPYRIGHT
Copyright © Tom Jakubowski. License AGPLv3: GNU Affero GPL Version 3
<a href="https://www.gnu.org/licenses/agpl-3.0.en.html">https://www.gnu.org/licenses/agpl-3.0.en.html</a>.
This is free software; you are free to change and redistribute it. There
is NO WARRANTY, to the extent permitted by law. For copying conditions and
source, see <a href="https://github.com/tomjakubowski/yasuc">https://github.com/tomjakubowski/yasuc</a>.
SEE ALSO
<a href="https://github.com/tomjakubowski/yasuc">http://github.com/tomjakubowski/yasuc</a>
</pre>
</body>
</html>
`
const adminLoginHTML = `
<!doctype html>
<html>
<head>
<title>YASUC Admin - Login</title>
<style>
body { font-family: Arial, sans-serif; max-width: 400px; margin: 50px auto; padding: 20px; }
.form-group { margin-bottom: 15px; }
label { display: block; margin-bottom: 5px; }
input[type="password"] { width: 100%; padding: 8px; border: 1px solid #ddd; border-radius: 4px; }
button { background: #007cba; color: white; padding: 10px 20px; border: none; border-radius: 4px; cursor: pointer; }
button:hover { background: #005a87; }
.error { color: red; margin-top: 10px; }
</style>
</head>
<body>
<h2>YASUC Admin Login</h2>
<form method="POST" action="/admin/login">
<div class="form-group">
<label for="password">Senha:</label>
<input type="password" id="password" name="password" required>
</div>
<button type="submit">Entrar</button>
{{if .Error}}
<div class="error">{{.Error}}</div>
{{end}}
</form>
</body>
</html>
`
const adminDashboardHTML = `
<!doctype html>
<html>
<head>
<title>YASUC Admin - Dashboard</title>
<style>
body { font-family: Arial, sans-serif; margin: 20px; }
.header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 20px; }
.logout { background: #dc3545; color: white; padding: 8px 16px; text-decoration: none; border-radius: 4px; }
.logout:hover { background: #c82333; }
table { width: 100%; border-collapse: collapse; margin-top: 20px; }
th, td { padding: 10px; text-align: left; border-bottom: 1px solid #ddd; }
th { background-color: #f8f9fa; }
.content-preview { max-width: 300px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.delete-btn { background: #dc3545; color: white; padding: 5px 10px; border: none; border-radius: 3px; cursor: pointer; }
.delete-btn:hover { background: #c82333; }
.view-btn { background: #007cba; color: white; padding: 5px 10px; text-decoration: none; border-radius: 3px; margin-right: 5px; }
.view-btn:hover { background: #005a87; }
.stats { background: #f8f9fa; padding: 15px; border-radius: 4px; margin-bottom: 20px; }
</style>
</head>
<body>
<div class="header">
<h1>YASUC Admin Dashboard</h1>
<a href="/admin/logout" class="logout">Sair</a>
</div>
<div class="stats">
<strong>Estatísticas:</strong> {{.TotalPastes}} pastes total | {{.TotalSize}} bytes
</div>
<table>
<thead>
<tr>
<th>ID</th>
<th>URL</th>
<th>Conteúdo</th>
<th>Tamanho</th>
<th>Criado em</th>
<th>Ações</th>
</tr>
</thead>
<tbody>
{{range .Pastes}}
<tr>
<td>{{.ShortID}}</td>
<td><a href="/{{.ShortID}}" target="_blank">{{.ShortID}}</a></td>
<td class="content-preview">{{.ContentPreview}}</td>
<td>{{.Size}} bytes</td>
<td>{{.CreatedAt}}</td>
<td>
<a href="/{{.ShortID}}" class="view-btn" target="_blank">Ver</a>
<button class="delete-btn" onclick="deletePaste('{{.ShortID}}')">Remover</button>
</td>
</tr>
{{end}}
</tbody>
</table>
<script>
function deletePaste(shortID) {
if (confirm('Tem certeza que deseja remover o paste ' + shortID + '?')) {
fetch('/admin/delete/' + shortID, {
method: 'POST',
headers: {
'Content-Type': 'application/json',
}
}).then(response => {
if (response.ok) {
location.reload();
} else {
alert('Erro ao remover paste');
}
});
}
}
</script>
</body>
</html>
`
type pasteTooLarge struct{}
func (e pasteTooLarge) Error() string {
return fmt.Sprintf("paste too large (maximum size %d bytes)", maxPasteSize)
}
// generateShortID gera um ID único de 7 caracteres
func generateShortID() string {
const charset = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
b := make([]byte, shortIDLength)
for i := range b {
b[i] = charset[rand.Intn(len(charset))]
}
return string(b)
}
// generateUniqueShortID gera um ID único que não existe no banco
func generateUniqueShortID(db *sql.DB) (string, error) {
maxAttempts := 100
for i := 0; i < maxAttempts; i++ {
id := generateShortID()
// Verificar se o ID já existe
var exists int
err := db.QueryRow("SELECT 1 FROM pastes WHERE short_id = ? LIMIT 1", id).Scan(&exists)
if err == sql.ErrNoRows {
return id, nil
}
if err != nil {
return "", err
}
}
return "", fmt.Errorf("não foi possível gerar um ID único após %d tentativas", maxAttempts)
}
func stashPaste(db *sql.DB, pasteStr string) (key string, err error) {
if len(pasteStr) > maxPasteSize {
err = pasteTooLarge{}
return
}
// Gerar ID curto único
shortID, err := generateUniqueShortID(db)
if err != nil {
return "", err
}
// Calcular hash SHA-256 para verificação de duplicatas
paste := []byte(pasteStr)
hash := sha256.Sum256(paste)
hashStr := hex.EncodeToString(hash[:])
// Verificar se já existe um paste com o mesmo conteúdo
var existingID string
err = db.QueryRow("SELECT short_id FROM pastes WHERE content_hash = ? LIMIT 1", hashStr).Scan(&existingID)
if err == nil {
// Paste já existe, retornar o ID existente
return existingID, nil
} else if err != sql.ErrNoRows {
return "", err
}
// Inserir novo paste
_, err = db.Exec("INSERT INTO pastes (short_id, content, content_hash, created_at) VALUES (?, ?, ?, ?)",
shortID, pasteStr, hashStr, time.Now().Unix())
if err != nil {
return "", err
}
return shortID, nil
}
type pasteNotFound struct{}
func (e pasteNotFound) Error() string {
return "not found"
}
func fetchPaste(db *sql.DB, key string) (paste string, err error) {
var content string
err = db.QueryRow("SELECT content FROM pastes WHERE short_id = ?", key).Scan(&content)
if err != nil {
if err == sql.ErrNoRows {
return "", pasteNotFound{}
}
return "", err
}
return content, nil
}
type Paste struct {
ShortID string
ContentPreview string
Size int
CreatedAt string
}
func getAllPastes(db *sql.DB) ([]Paste, error) {
rows, err := db.Query(`
SELECT short_id, content, created_at
FROM pastes
ORDER BY created_at DESC
`)
if err != nil {
return nil, err
}
defer rows.Close()
var pastes []Paste
for rows.Next() {
var p Paste
var content string
var createdAt int64
err := rows.Scan(&p.ShortID, &content, &createdAt)
if err != nil {
return nil, err
}
p.Size = len(content)
if len(content) > 50 {
p.ContentPreview = content[:50] + "..."
} else {
p.ContentPreview = content
}
p.CreatedAt = time.Unix(createdAt, 0).Format("02/01/2006 15:04:05")
pastes = append(pastes, p)
}
return pastes, nil
}
func deletePaste(db *sql.DB, shortID string) error {
result, err := db.Exec("DELETE FROM pastes WHERE short_id = ?", shortID)
if err != nil {
return err
}
rowsAffected, err := result.RowsAffected()
if err != nil {
return err
}
if rowsAffected == 0 {
return pasteNotFound{}
}
return nil
}
func getStats(db *sql.DB) (totalPastes int, totalSize int64, err error) {
err = db.QueryRow("SELECT COUNT(*), SUM(LENGTH(content)) FROM pastes").Scan(&totalPastes, &totalSize)
if err == sql.ErrNoRows {
return 0, 0, nil
}
return totalPastes, totalSize, err
}
type handler struct {
db *sql.DB
adminPassword string
}
func (h *handler) alles(w http.ResponseWriter, req *http.Request) {
if req.URL.Path != "/" {
paste, err := fetchPaste(h.db, req.URL.Path[1:])
if err != nil {
if _, ok := err.(pasteNotFound); ok {
http.Error(w, "not found", http.StatusNotFound)
} else {
http.Error(w, err.Error(), http.StatusInternalServerError)
}
return
}
fmt.Fprintf(w, "%s", paste)
return
}
if req.Method == http.MethodPost {
body := req.FormValue("sprunge")
// sprunge.us proceeds if there's no form data in 'sprunge', and just makes
// an empty paste.
key, err := stashPaste(h.db, body)
if err != nil {
if _, ok := err.(pasteTooLarge); ok {
http.Error(w, err.Error(), http.StatusNotAcceptable)
} else {
http.Error(w, err.Error(), http.StatusInternalServerError)
}
return
}
baseURL := fmt.Sprintf("https://%s", req.Host)
fmt.Fprintf(w, "%s/%s\n", baseURL, key)
return
}
// usage message
tmpl, err := template.New("usage").Parse(usageText)
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
baseURL := fmt.Sprintf("https://%s", req.Host)
data := struct{ BaseURL string }{baseURL}
_ = tmpl.Execute(w, data)
}
func (h *handler) adminLogin(w http.ResponseWriter, req *http.Request) {
if req.Method == http.MethodPost {
password := req.FormValue("password")
if password == h.adminPassword {
// Set session cookie
http.SetCookie(w, &http.Cookie{
Name: "admin_session",
Value: "authenticated",
Path: "/admin",
MaxAge: 3600, // 1 hour
HttpOnly: true,
})
http.Redirect(w, req, "/admin/dashboard", http.StatusSeeOther)
return
}
// Show error
tmpl, _ := template.New("login").Parse(adminLoginHTML)
data := struct{ Error string }{"Senha incorreta"}
tmpl.Execute(w, data)
return
}
// Show login form
tmpl, _ := template.New("login").Parse(adminLoginHTML)
data := struct{ Error string }{""}
tmpl.Execute(w, data)
}
func (h *handler) adminLogout(w http.ResponseWriter, req *http.Request) {
http.SetCookie(w, &http.Cookie{
Name: "admin_session",
Value: "",
Path: "/admin",
MaxAge: -1,
HttpOnly: true,
})
http.Redirect(w, req, "/admin/login", http.StatusSeeOther)
}
func (h *handler) checkAuth(w http.ResponseWriter, req *http.Request) bool {
cookie, err := req.Cookie("admin_session")
if err != nil || cookie.Value != "authenticated" {
http.Redirect(w, req, "/admin/login", http.StatusSeeOther)
return false
}
return true
}
func (h *handler) adminDashboard(w http.ResponseWriter, req *http.Request) {
if !h.checkAuth(w, req) {
return
}
pastes, err := getAllPastes(h.db)
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
totalPastes, totalSize, err := getStats(h.db)
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
data := struct {
Pastes []Paste
TotalPastes int
TotalSize int64
}{
Pastes: pastes,
TotalPastes: totalPastes,
TotalSize: totalSize,
}
tmpl, _ := template.New("dashboard").Parse(adminDashboardHTML)
tmpl.Execute(w, data)
}
func (h *handler) adminDelete(w http.ResponseWriter, req *http.Request) {
if !h.checkAuth(w, req) {
return
}
if req.Method != http.MethodPost {
http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
return
}
// Extract shortID from URL path
pathParts := strings.Split(req.URL.Path, "/")
if len(pathParts) != 4 {
http.Error(w, "Invalid URL", http.StatusBadRequest)
return
}
shortID := pathParts[3]
err := deletePaste(h.db, shortID)
if err != nil {
if _, ok := err.(pasteNotFound); ok {
http.Error(w, "Paste not found", http.StatusNotFound)
} else {
http.Error(w, err.Error(), http.StatusInternalServerError)
}
return
}
w.WriteHeader(http.StatusOK)
w.Write([]byte("Paste deleted successfully"))
}
func newHandler(db *sql.DB, adminPassword string) http.Handler {
h := handler{db: db, adminPassword: adminPassword}
mux := http.NewServeMux()
mux.HandleFunc("/", h.alles)
mux.HandleFunc("/admin/login", h.adminLogin)
mux.HandleFunc("/admin/logout", h.adminLogout)
mux.HandleFunc("/admin/dashboard", h.adminDashboard)
mux.HandleFunc("/admin/delete/", h.adminDelete)
return mux
}
func initDatabase(db *sql.DB) error {
// Create the pastes table if it doesn't exist
_, err := db.Exec(`
CREATE TABLE IF NOT EXISTS pastes (
short_id TEXT PRIMARY KEY,
content TEXT NOT NULL,
content_hash TEXT NOT NULL,
created_at INTEGER NOT NULL
)
`)
if err != nil {
return err
}
// Create indexes for better performance
_, err = db.Exec(`CREATE INDEX IF NOT EXISTS idx_pastes_content_hash ON pastes(content_hash)`)
if err != nil {
return err
}
_, err = db.Exec(`CREATE INDEX IF NOT EXISTS idx_pastes_created_at ON pastes(created_at)`)
return err
}
func main() {
// Initialize random seed
rand.Seed(time.Now().UnixNano())
var dbPath, addr string
var port int
flag.StringVar(&dbPath, "db", "", "location of database file")
flag.StringVar(&addr, "addr", "", "bind address")
flag.IntVar(&port, "port", 9001, "bind port")
flag.Parse()
if dbPath == "" {
fmt.Fprintf(os.Stderr, "db option is required\n")
os.Exit(1)
}
// Get admin password from environment variable
adminPassword := os.Getenv("YASUC_ADMIN_PASSWORD")
if adminPassword == "" {
adminPassword = "admin123" // Default password
log.Println("Warning: YASUC_ADMIN_PASSWORD not set, using default password 'admin123'")
}
// Open SQLite database
db, err := sql.Open("sqlite", dbPath)
if err != nil {
log.Fatal(err)
}
defer func() { _ = db.Close() }()
// Initialize database schema
err = initDatabase(db)
if err != nil {
log.Fatal(err)
}
http.Handle("/", newHandler(db, adminPassword))
sockAddr := fmt.Sprintf("%s:%d", addr, port)
log.Fatal(http.ListenAndServe(sockAddr, nil))
}