go-sendxmpp/handlemechanisminfo.go

// Copyright Martin Dosch.
// Use of this source code is governed by the BSD-2-clause
// license that can be found in the LICENSE file.

package main

import (
	"errors"
	"fmt"
	"os"
	"os/user"
	"strings"
)

func findPinFilePath(username string) (string, error) {
	osDataDir := os.Getenv("$XDG_DATA_HOME")
	if osDataDir == "" {
		// Get the current user.
		curUser, err := user.Current()
		if err != nil {
			return strError, fmt.Errorf("findConfig: failed to get current user: %w", err)
		}
		// Get home directory.
		home := curUser.HomeDir
		if home == "" {
			return strError, errors.New("no home directory found")
		}
		osDataDir = home + "/.local/share/"
	}
	authPinFilePath := osDataDir + "/go-sendxmpp/" + username + "/"

	return authPinFilePath, nil
}

// Opens the auth mechanism pin file and returns the value.
func parsePinFile(user string) (string, error) {
	// Find auth pin file
	authPinFile, err := findPinFilePath(user)
	if err != nil {
		return "", err
	}

	// Read file.
	m, err := os.ReadFile(authPinFile + "authmechanism")
	if err != nil {
		return "", err
	}
	// Strip trailing newline.
	mechanism := strings.TrimSuffix(string(m), "\n")

	return mechanism, nil
}

// Writes the used mechanism to the auth pin file.
func writePinFile(mechanism string, user string) error {
	// Find auth pin file
	authPinFilePath, err := findPinFilePath(user)
	if err != nil {
		return err
	}
	if _, err = os.Stat(authPinFilePath); os.IsNotExist(err) {
		err = os.MkdirAll(authPinFilePath, defaultDirRights)
		if err != nil {
			return fmt.Errorf("writePinFile: could not create folder for auth pin file: %w", err)
		}
	}
	err = os.WriteFile(authPinFilePath+"authmechanism", []byte(mechanism+"\n"), 0o400)
	if err != nil {
		return err
	}
	return nil
}