osbre

osbre

Is there a specification or recommendations on implementing “one-time authentication” link?

Hello everyone

I’m trying to implement a “magic link” or “one-time login link” functionality

I wonder what a secure way to implement it would be.

The obvious and most simple solution to me seems to be generating a long enough string and storing it in the database.

When the link is opened, the app will just check the value against the database, and verify that it has not expired based on the creation date

But, an alternative way is to use encryption. Seems beneficial because it does not involve the generation of long enough string? As we can encrypt only database identifier which leads to a record of when the login request was made (to check if not expired)

I appreciate any feedback or tips, thanks :pray:

Marked As Solved

OvermindDL1

OvermindDL1

That’s basically what that “long enough string” is, when its long enough and random then you have enough entropy to not worry about it. Just using a UUIDv4 is enough entropy to not worry about it if it expires anywhere in the next thousand years, lol.

Except you encrypt it, which means it’s going to balloon in size to get enough entropy to be worth encrypting, which is going to end up longer in the URL anyway.

Also Liked

AstonJ

AstonJ

If the user has an account then I generally use SecureRandom to generate a random url-safe string then put that in the db associated with the user and an expiry, then in the URL params I will add the user’s ID as well as the generated string, that way the ID must correspond with the string, or it won’t work :023:

There’s an Elixir library for SecureRandom:

iex> SecureRandom.urlsafe_base64
"xYQcVfWuq6THMY_ZVmG0mA"

Where Next?

Popular Backend topics Top

DevotionGeo
I know that -t flag is used along with -i flag for getting an interactive shell. But I cannot digest what the man page for docker run com...
New
IhorYachmenov
Hello. I have an iOS app where needs a proxying website through private server(HTTP / HTTPS proxy), but its idea each time has some trou...
New
Jsdr3398
I’ve been working on and rewriting my messaging platform several times for the past two years. With Discords new rebranding, it has reall...
New
mrmurphy
I’ve run into a situation where I’ve got a list of posts inside of a container that uses phx-update=“prepend”, and the posts on the socke...
New
Ookma-Kyi
I am learning Elixir at the moment but am finding it difficult to learn. The issue is there aren’t any good tutorial sites out there when...
New
osbre
Hello everyone I’m trying to implement a “magic link” or “one-time login link” functionality I wonder what a secure way to implement it...
New
MarkIden
Hi, Recommend pls your favorite learning resources in Go, with best books, podcasts etc.
/go
New
AstonJ
If when trying to create (or recreate) your dev db with rails db:create you are getting: PG::ConnectionBad: connection to server on soc...
New
Fl4m3Ph03n1x
Background When trying to execute mix release on a Windows 11 machine for a Phoenix project I get the following error: * assembling mark...
New
yamuna
Hi everyone, I’m trying to run deepseek-coder:6.7b-instruct-q4_K_M in Docker using Ollama to create an LLM that will be used by CrewAI a...
New

Other popular topics Top

PragmaticBookshelf
Machine learning can be intimidating, with its reliance on math and algorithms that most programmers don't encounter in their regular wor...
New
PragmaticBookshelf
Rust is an exciting new programming language combining the power of C with memory safety, fearless concurrency, and productivity boosters...
New
AstonJ
If you are experiencing Rails console using 100% CPU on your dev machine, then updating your development and test gems might fix the issu...
New
AstonJ
Continuing the discussion from Thinking about learning Crystal, let’s discuss - I was wondering which languages don’t GC - maybe we can c...
New
AstonJ
We’ve talked about his book briefly here but it is quickly becoming obsolete - so he’s decided to create a series of 7 podcasts, the firs...
New
New
Help
I am trying to crate a game for the Nintendo switch, I wanted to use Java as I am comfortable with that programming language. Can you use...
New
PragmaticBookshelf
Author Spotlight: VM Brasseur @vmbrasseur We have a treat for you today! We turn the spotlight onto Open Source as we sit down with V...
New
RobertRichards
Hair Salon Games for Girls Fun Girls Hair Saloon game is mainly developed for kids. This game allows users to select virtual avatars to ...
New
PragmaticBookshelf
A concise guide to MySQL 9 database administration, covering fundamental concepts, techniques, and best practices. Neil Smyth MySQL...
New