SQL注入是一種注入攻擊手段,經過執行惡意SQL語句,進而將任意SQL代碼插入數據庫查詢,從而使攻擊者徹底控制Web應用程序後臺的數據庫服務器。攻擊者可使用SQL注入漏洞繞過應用程序驗證,好比繞過登陸驗證登陸Web身份驗證和受權頁面;也能夠繞過網頁,直接檢索數據庫的全部內容;還能夠惡意修改、刪除和增長數據庫內容。html
咱們採起了第二條思路和方法,即不用動態拼接SQL語句的方法,而是使用參數化查詢,即變量綁定。mysql
下面給出SQL注入攻擊安全漏洞代碼——拼接SQL語句:git
//數據庫 /* Navicat Premium Data Transfer Source Server : localhost_3306 Source Server Type : MySQL Source Server Version : 50553 Source Host : localhost:3306 Source Schema : test Target Server Type : MySQL Target Server Version : 50553 File Encoding : 65001 Date: 28/02/2020 10:48:06 */ SET NAMES utf8mb4; SET FOREIGN_KEY_CHECKS = 0; -- ---------------------------- -- Table structure for userinfo -- ---------------------------- DROP TABLE IF EXISTS `userinfo`; CREATE TABLE `userinfo` ( `uid` int(10) NOT NULL AUTO_INCREMENT, `username` varchar(64) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL, `password` varchar(64) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL, PRIMARY KEY (`uid`) USING BTREE ) ENGINE = MyISAM AUTO_INCREMENT = 14 CHARACTER SET = latin1 COLLATE = latin1_swedish_ci ROW_FORMAT = Dynamic; -- ---------------------------- -- Records of userinfo -- ---------------------------- INSERT INTO `userinfo` VALUES (2, 'aaa', 'hh'); INSERT INTO `userinfo` VALUES (4, 'ast', 'dddd'); SET FOREIGN_KEY_CHECKS = 1;
//test.go package main import ( "database/sql" "fmt" _ "github.com/go-sql-driver/mysql" "html/template" "log" "net/http" "strings" ) func login(w http.ResponseWriter, r *http.Request) { fmt.Println("method:", r.Method) //獲取請求的方法 if r.Method == "GET" { t, _ := template.ParseFiles("D:/Golang/GoItem/go_ex/goSql/test.html") t.Execute(w, nil) } else { //請求的是查詢數據,那麼執行查詢的邏輯判斷 r.ParseForm() fmt.Println("username:", r.Form["username"]) var sename = strings.Join(r.Form["username"], "") var partname = strings.Join(r.Form["password"], "") db, err := sql.Open("mysql", "root:123456@/test?charset=utf8") infoErr(err) if sename != "" && partname != "" { var uid int var username string var password string //字符串拼接查詢 err := db.QueryRow("SELECT * FROM userinfo WHERE username ='"+sename+"'AND password ='"+partname+"'"). Scan(&uid, &username, &password) infoErr(err) //判斷返回的數據是否爲空 if err == sql.ErrNoRows { fmt.Fprintf(w, "無該用戶數據") } else { if (sename == username) && (partname == password) { fmt.Println(uid) fmt.Println(username) fmt.Println(password) t, _ := template.ParseFiles("D:/Golang/GoItem/go_ex/goSql/success.html") t.Execute(w, nil) } } } else if sename == "" || partname == "" { fmt.Fprintf(w, "錯誤,輸入不能爲空!") } } } func infoErr(err error) { if err != nil { panic(err) } } func main() { http.HandleFunc("/login",login) //設置訪問的路由 //設置訪問的路由 err := http.ListenAndServe(":9092", nil) //設置監聽的端口 if err != nil { log.Fatal("ListenAndServe: ", err) } }
//login.html <html> <head> <meta charset="utf-8" /> <title>sql防注入</title> <style> form{ width: 30vw; height: 30vh; min-height: 300px; margin: 10vh auto; border: 1px solid; border-radius: 4px; } form .username,.password{ display: block; float: right; } div { width: 300px; height: 80px; margin: 30px auto 0; } input label { float: left; display: inline-block; } input { height: 30px; } .button { width: 100px; margin: auto; clear: both; display: block; } </style> </head> <body> <form action="/login" method="post"> <div> <label>username: </label> <input class="username" type="text" name="username"> </div> <div> <label>password:</label> <input class="password" type="text" name="password"> </div> <input class="button" type="submit" value="查詢"> </form> </body> </html>
解決防SQL注入方案——參數化查詢:github
//test.go package main import ( "database/sql" "fmt" _ "github.com/go-sql-driver/mysql" "html/template" "log" "net/http" "strings" ) func login(w http.ResponseWriter, r *http.Request) { fmt.Println("method:", r.Method) //獲取請求的方法 if r.Method == "GET" { t, _ := template.ParseFiles("D:/Golang/GoItem/go_ex/goSql/login.html") t.Execute(w, nil) } else { //請求的是查詢數據,那麼執行查詢的邏輯判斷 r.ParseForm() fmt.Println("username:", r.Form["username"]) var sename = strings.Join(r.Form["username"], "") var partname = strings.Join(r.Form["password"], "") db, err := sql.Open("mysql", "root:123456@/test?charset=utf8") checkErr(err) if sename != "" && partname != "" { var uid int var username string var password string //參數查詢在必定程度上防止sql注入,參數化查詢主要作了兩件事: //1.參數過濾;2.執行計劃重用 //由於執行計劃被重用,因此能夠防止SQL注入。 err := db.QueryRow("SELECT * FROM userinfo WHERE username = ? AND password = ?", sename, partname). Scan(&uid, &username, &password) //判斷返回的數據是否爲空 if err == sql.ErrNoRows { fmt.Fprintf(w, "無該用戶數據") } else { if (sename == username) && (partname == password) { fmt.Println(uid) fmt.Println(username) fmt.Println(password) t, _ := template.ParseFiles("D:/Golang/GoItem/go_ex/goSQL/success.html") t.Execute(w, nil) } } } else if sename == "" || partname == "" { fmt.Fprintf(w, "錯誤,輸入不能爲空!") } } } func checkErr(err error) { if err != nil { panic(err) } } func main() { http.HandleFunc("/login", login) //設置訪問的路由 err := http.ListenAndServe(":9090", nil) //設置監聽的端口 if err != nil { log.Fatal("ListenAndServe: ", err) } }
執行登陸查詢的數據庫語句:"SELECT * FROM userinfo WHERE username ='"+sename+"'AND password ='"+partname+"'"
正則表達式
當查詢到數據表中存在同時知足 username 和 password 字段時,會返回用戶信息。 嘗試在用戶名中輸入 123' or 1=1 #, 密碼一樣輸入 123' or 1=1 # ,實際執行的SQL語句是select * from users where username='123' or '1'='1' and password='123' or '1'='1
sql
則會出現一個空白頁面,其實此時SQl注入已經繞過驗證進入到須要身份驗證的頁面。數據庫
而若是執行"SELECT * FROM userinfo WHERE username = ? AND password = ?", sename, partname
安全
再次輸入123' or 1=1 #,則會被攔截下來,顯示無該用戶數據。服務器
咱們須要知道參數化查詢都作了些什麼事:工具
1.參數過濾;
2.執行計劃重用
它的原理是採用了預編譯的方法,先將SQL語句中可被客戶端控制的參數集進行編譯,生成對應的臨時變量集,再使用對應的設置方法,爲臨時變量集裏面的元素進行賦值,而QueryRow()方法會對傳入參數進行強制類性檢查和安全檢查,因此就避免了SQL注入的產生。
QueryRow("SELECT * FROM userinfo WHERE username = ? AND password = ?", sename, partname). Scan(&uid, &username, &password)