如何提升Golang框架的安全性

import (
    "crypto/tls"
    "crypto/x509"
    "io/ioutil"
    "log"
    "net/http"
)

func main() {
    cert, err := tls.LoadX509KeyPair("cert.pem", "key.pem")
    if err != nil {
        log.Fatal(err)
    }

    pool := x509.NewCertPool()
    caCert, err := ioutil.ReadFile("ca.pem")
    if err != nil {
        log.Fatal(err)
    }

    pool.AppendCertsFromPEM(caCert)

    tlsConf := &tls.Config{
        Certificates: []tls.Certificate{cert},
        RootCAs:      pool,
    }

    srv := &http.Server{
        Addr:      ":443",
        Handler:   http.DefaultServeMux,
        TLSConfig: tlsConf,
    }

    log.Fatal(srv.ListenAndServeTLS("", ""))
}

func validateInput(input string) (string, error) {
    r := regexp.MustCompile(`[^a-zA-Z0-9]+`)
    validated := r.ReplaceAllString(input, "")
    if validated != input {
        return "", errors.New("Invalid input")
    }
    return validated, nil
}

import (
    "net/http"
    "time"

    "github.com/golang-jwt/jwt"
)

var jwtKey = []byte("secret")

func generateJWT(userID string) (string, error) {
    claims := jwt.StandardClaims{
        ExpiresAt: time.Now().Add(time.Hour).Unix(),
        Subject:   userID,
    }
    return jwt.NewWithClaims(jwt.SigningMethodHS256, claims).SignedString(jwtKey)
}

func verifyJWT(token string) (string, error) {
    t, err := jwt.ParseWithClaims(token, &jwt.StandardClaims{}, func(token *jwt.Token) (interface{}, error) {
        return jwtKey, nil
    })
    if err != nil {
        return "", err
    }

    if claims, ok := t.Claims.(*jwt.StandardClaims); ok && t.Valid {
        return claims.Subject, nil
    }

    return "", errors.New("Invalid token")
}

func middleware(next http.Handler) http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        token := r.Header.Get("Authorization")
        if token == "" {
            w.WriteHeader(http.StatusUnauthorized)
            return
        }

        userID, err := verifyJWT(token)
        if err != nil {
            w.WriteHeader(http.StatusUnauthorized)
            return
        }

        r.Context().Value("userID") = userID
        next.ServeHTTP(w, r)
    })
}

import (
    "crypto/rand"
    "encoding/base64"
    "net/http"

    "github.com/gorilla/mux"
)

var users = make(map[string]string)

func main() {
    r := mux.NewRouter()
    r.Use(secureHeaders)

    r.HandleFunc("/users", createUser).Methods(http.MethodPost)
    r.HandleFunc("/users/{id}", getUser).Methods(http.MethodGet)

    http.ListenAndServe(":8080", r)
}

func createUser(w http.ResponseWriter, r *http.Request) {
    username := r.FormValue("username")
    password := r.FormValue("password")

    if username == "" || password == "" {
        w.WriteHeader(http.StatusBadRequest)
        return
    }

    salt := make([]byte, 16)
    _, err := rand.Read(salt)
    if err != nil {
        w.WriteHeader(http.StatusInternalServerError)
        return
    }

    passwordHash := hashPassword(password, salt)
    users[username] = base64.StdEncoding.EncodeToString(passwordHash)

    w.WriteHeader(http.StatusCreated)
}

func getUser(w http.ResponseWriter, r *http.Request) {
    params := mux.Vars(r)
    username := params["id"]

    passwordHash, ok := users[username]
    if !ok {
        w.WriteHeader(http.StatusNotFound)
        return
    }

    w.Write([]byte(passwordHash))
}