61 lines
1.3 KiB
Go
61 lines
1.3 KiB
Go
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package security
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import (
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"crypto/rand"
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"encoding/hex"
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"log"
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"math"
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"net/http"
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"time"
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)
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// GenerateCsrfToken generates a csrf token and assigns it to a cookie for double submit cookie csrf protection
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func GenerateCsrfToken(w http.ResponseWriter, r *http.Request) (string, error) {
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// Generate random 64 character string (alpha-numeric)
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buff := make([]byte, int(math.Ceil(float64(64)/2)))
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_, err := rand.Read(buff)
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if err != nil {
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log.Println("Error creating random buffer for token value")
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log.Println(err)
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return "", err
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}
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str := hex.EncodeToString(buff)
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token := str[:64]
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// Create session cookie, containing token
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cookie := &http.Cookie{
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Name: "csrf",
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Value: token,
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Path: "/",
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MaxAge: 1800,
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Expires: time.Now().Add(24 * time.Hour),
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HttpOnly: true,
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Secure: true,
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}
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http.SetCookie(w, cookie)
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return token, nil
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}
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// VerifyCsrfToken verifies the csrf token
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func VerifyCsrfToken(r *http.Request) (bool, error) {
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// Get csrf cookie
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cookie, err := r.Cookie("csrf")
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if err != nil {
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log.Println("Error getting csrf cookie")
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log.Println(err)
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return false, err
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}
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// Get csrf token from form
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token := r.FormValue("csrf")
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// Compare csrf cookie and csrf token
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if cookie.Value == token {
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return true, nil
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}
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return false, nil
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}
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