users.go

  1// SPDX-FileCopyrightText: Amolith <amolith@secluded.site>
  2//
  3// SPDX-License-Identifier: Apache-2.0
  4
  5package users
  6
  7import (
  8	"crypto/rand"
  9	"database/sql"
 10	"encoding/base64"
 11	"time"
 12
 13	"git.sr.ht/~amolith/willow/db"
 14	"golang.org/x/crypto/argon2"
 15)
 16
 17// argonHash accepts two strings for the user's password and a random salt,
 18// hashes the password using the salt, and returns the hash as a base64-encoded
 19// string.
 20func argonHash(password, salt string) (string, error) {
 21	decodedSalt, err := base64.StdEncoding.DecodeString(salt)
 22	if err != nil {
 23		return "", err
 24	}
 25	return base64.StdEncoding.EncodeToString(argon2.IDKey([]byte(password), decodedSalt, 2, 64*1024, 4, 64)), nil
 26}
 27
 28// generateSalt generates a random salt and returns it as a base64-encoded
 29// string.
 30func generateSalt() (string, error) {
 31	salt := make([]byte, 16)
 32	_, err := rand.Read(salt)
 33	if err != nil {
 34		return "", err
 35	}
 36	return base64.StdEncoding.EncodeToString(salt), nil
 37}
 38
 39// Register accepts a username and password, hashes the password and stores the
 40// hash and salt in the database.
 41func Register(dbConn *sql.DB, username, password string) error {
 42	salt, err := generateSalt()
 43	if err != nil {
 44		return err
 45	}
 46
 47	hash, err := argonHash(password, salt)
 48	if err != nil {
 49		return err
 50	}
 51
 52	return db.CreateUser(dbConn, username, hash, salt)
 53}
 54
 55// Delete removes a user from the database.
 56func Delete(dbConn *sql.DB, username string) error { return db.DeleteUser(dbConn, username) }
 57
 58// UserAuthorised accepts a username string, a token string, and returns true if the
 59// user is authorised, false if not, and an error if one is encountered.
 60func UserAuthorised(dbConn *sql.DB, username, token string) (bool, error) {
 61	dbHash, dbSalt, err := db.GetUser(dbConn, username)
 62	if err != nil {
 63		return false, err
 64	}
 65
 66	providedHash, err := argonHash(token, dbSalt)
 67	if err != nil {
 68		return false, err
 69	}
 70
 71	return dbHash == providedHash, nil
 72}
 73
 74// SessionAuthorised accepts a session string and returns true if the session is
 75// valid and false if not.
 76func SessionAuthorised(dbConn *sql.DB, session string) (bool, error) {
 77	dbResult, expiry, err := db.GetSession(dbConn, session)
 78	if dbResult == "" || expiry.Before(time.Now()) || err != nil {
 79		return false, err
 80	}
 81
 82	return true, nil
 83}
 84
 85// InvalidateSession invalidates a session by setting the expiration date to now.
 86func InvalidateSession(dbConn *sql.DB, session string) error {
 87	return db.InvalidateSession(dbConn, session, time.Now())
 88}
 89
 90// CreateSession accepts a username, generates a token, stores it in the
 91// database, and returns it.
 92func CreateSession(dbConn *sql.DB, username string) (string, time.Time, error) {
 93	token, err := generateSalt()
 94	if err != nil {
 95		return "", time.Time{}, err
 96	}
 97
 98	expiry := time.Now().Add(7 * 24 * time.Hour)
 99
100	err = db.CreateSession(dbConn, username, token, expiry)
101	if err != nil {
102		return "", time.Time{}, err
103	}
104
105	return token, expiry, nil
106}
107
108// GetUsers returns a list of all users in the database as a slice of strings.
109func GetUsers(dbConn *sql.DB) ([]string, error) { return db.GetUsers(dbConn) }