How to re-hash Laravel passwords? - hash

I'm making a forget password feature in my web app, problem is I store user's password using:
Hash::make('_their_password_')
Is there any way to re-hash it back or any recommended approach for this?

The point of hashing a password is that it's (supposed to be) an irreversible operation. If your database is compromised, the attacker will gain access to the hashes, but not to the passwords. That way the attacker can't log in with the users' passwords on other sites.
Make a "we'll reset your password" feature instead of a "we'll send you your password" feature.
Note that there are also other best practices you absolutely should be following regarding password hashing, to make sure the "supposed to be" above actually holds, and to further minimize the impact if your site is compromised. Laravel's Hash class seems to already be using the password-appropriate hash function Bcrypt. However, make sure you're using a salt when you're hashing your password.

The Laravel's Hash method cannot be reversed.
One way encryption is the best way to store user passwords, or other sensitive data.
One way means that your data can be converted into an encrypted string, but due to a complex algorithm with painful maths, reversing the process is not possible. This makes storing passwords a doddle! Your customers don't have to worry about you knowing their passwords, but you are still able to compare them (by hashing the password they provide) or change the password if needed.
If you need to reverse, you can use Crypter class.
$secret = Crypter::encrypt('I actually like Hello Kitty');
$decrypted_secret = Crypter::decrypt($secret);
Read more about encryption here http://codehappy.daylerees.com/encryption

If you want to verify the content of password with other value use the following.
return Hash::check($value, auth()->user()->password);

Related

Keycloak reset user password via REST API by hash

The CredentialRepresentation used in the Keycloak 'reset-password' REST API contains fields for hashing algorithm, hashed password, hashing iterations etc.
This implicates that I can pass through a hashed password and all its hashing specifications, instead of passing the plain-text password to the service. This is exactly what I'd like to do, because passing a plain-text password doesn't feel right.
When I try to call the service without the plain-text value however, I get a 400 error with the error message that the plain-text value is missing. Is there any way to pass just the hashed password?
Passing in a plaintext password (via HTTPS of course) allows keycloak to hash it using the hash algorithm policy of the realm.
If you want to pass in the hashed password value, iterations and algorithm then you also need to provide the hashing SPI that implements PasswordHashProviderFactory and PasswordHashProvider. And I don't think this is available via the reset-password API, but would work with the Update User API (I haven't tested this).
Rather than specifying a new password manually a better security practice is to use the PUT /admin/realms/{realm}/users/{id}/execute-actions-email admin call with "UPDATE_PASSWORD" as the required action. This causes Keycloak to send an email to the user that gives a link to set a new password directly.

Decrypting rfc2898 password

I'm in the middle of development and I need to test my login/password api.
Problem is in the database the password is encrypted.
I have the following information.
key
iteration
salt
Is this enough to recover the password?
By the way I can edit these values as well if that will help.
I think you misunderstood, how a password API works. You cannot reverse a properly hashed password, but you can validate an entered password against the stored hash.
To validate the entered password, you need to calculate the hash again, with the same parameters you used to create the first hash. Then you can compare the two hashes, if they match, the password was the same.
You cannot reverse PBKDF2, but you could brute-force the common passwords to see if any of them matches. If a random salt is used every time, then you will need to do that for each password independently. If a large iteration count is used then prepare for it to take very long.
First, you should just reset it.
Second, you can recover it if and only if the password was weak (assuming correctly implemented PBKDF2), and you either know which HMAC it used (probably was PBKDF2-HMAC-SHA-1 - test with a known password), or you're willing to spend time trying several and hoping.
Try a tool like oclHashcat that's designed for password cracking - note PBKDF2 generic at the end of the list of examples for this, preferably with one or more good GPUs.
Alternately, if you're just testing your password API, you can run the test vectors at my Github repository through it and see if your results are correct or not.

Apache Shiro salt hashed password

I need to salt a hashed(SHA-256) password using Apache Shiro. I used the following method, but it uses plainText password as a parameter. But I need to get an alredy hashed password from the frontend and salt it and store in the server side. Otherwise if I use the following method I will have to pass the plain password all the way through frontend, which is not secure. So please suggest me a way to overcome this problem.
String hashedPassword = new Sha256Hash(plainTextPassword, salt);
You cannot salt the password after it has been hashed. Salting works by combining the salt with the plain text password, and hashing the entire thing. This is why Shiro's Sha256Hash requires you to give it the plain text password.
It is common to pass the plain text password from the front end to the service layer as long as this communication is secure (e.g. HTTPS for web UIs). The only thing you should not do is store the plain text password in a database (which a correctly configured Shiro will not do) because your database may be compromised.
When passing the plain text password from the front end to your service, it will only exist in memory for a short time before being garbage collected. To obtain the password someone would have to either break your SSL connection (in which case you are screwed anyway) or compromise your server and dump the memory (in which case you are screwed anyway).

How to hide value in database PostgreSQL

Anybody can help me regarding the database postgres?
I need to hide the value in table that was created.I need to hide the data password as like below example:
username password
ana 123
I want the password appear like *
Can anyone help me? Thank you in advance.
Take a look at pgcrypto module for some more options (like Extended DES crypt and PGP encryption). I don't recommend using MD5, because (IMHO) it's easily breakable nowadays (especially without any salt). Better choice is SHA-512 (or some of SHA-3 candidates: BLAKE, Grøstl etc.).
I think that it's good idea to check your hiding method against some (possibly GPU-accelerated) tools like hashcat. It really depends how valuable data you want to store.
The usual, and best, way is to store the MD5 of the password and compare that with the MD5 of the password entered. It fairly safe (but brute force can crack it given enough time).
One standard method of doing that sort of hiding is by creating a view, with all columns except the password column (or all columns, then '*' AS password). For the db user the application uses to connect, grant read access to the view, but remove read access for the source table. That way there is no chance of the application gaining access to the field.
Something like:
CREATE VIEW visible_users AS
SELECT username, '***' as password
FROM users;
Then make sure the privileges are managed appropriately:
REVOKE ALL ON users FOR app_user;
That said, you probably shouldn't be storing passwords in a database in plaintext -- it's a major potential security issue.

What is the standard way to create a "key" from a value?

I need to take a user's email address and somehow manipulate the value to come up with an auto-generated password. I want to make sure that I can re-create the same password whenever a user needs to retrieve their password.
Is there a standard way of doing this? Is this what a "hash" is? I would be greatly appreciative if someone could point me in the right direction! :) Once I know where to look, I can do the research myself.
Thanks!
Sunny
Yes, that's what a "hash" is. However, I would strongly caution against this approach, because it means that someone who's good at cryptographic analysis could potentially generate the password for any user on the system, just by knowing their email address.
Standard practice in the case you're suggesting is to actually reset the user's password with a new, random password when they forget their password. That keeps their previous password "safe," so that someone happens to intercept the email with their password, it will only contain a random password rather than a password that the user very likely uses for every other website they log in to.
After a password reset, users should be encouraged to change their password when they first log in.
A hashing function does do what you're looking for - it takes some input x and generates a digest d that will be the same whenever you give it input x again.
A better definition from wikipedia, that explains this property:
Determinism
A hash procedure must be deterministic—meaning that for a given input value it must always generate the same hash value. In other words, it must be a function of the hashed data, in the mathematical sense of the term. This requirement excludes hash functions that depend on external variable parameters, such as pseudo-random number generators that depend on the time of day. It also excludes functions that depend on the memory address of the object being hashed, if that address may change during processing (as may happen in systems that use certain methods of garbage collection), although sometimes rehashing of the item can be done.
However, if this is for password retrieval, I would advise against it. Instead, I would recommend the approach of sending them a link to reset their password, and then have them reset their password.
If you are doing some sort of password reset system, you should just randomly generate a password to their email and than force them to change it on initial login. If they need to reset their password at some other time, than they can go through the same process again.
Something like the md5 function in PHP would be a good place to start. However, why would you need to recreate the same autogenerated password if the user lost it ? Personally, it would make more sense to just generate a new random one.
A Hash is like a fingerprint. If you have the original value (the password for example), you can get the fingerprint and compare to the one you have in your database. But with the fingerprint you have in the database, you can't recreate the original value (you can't create an human from a fingerprint).
It seems to be what you want. But even so it could be not what you need. Generating a password from the hash of an email address means that anyone that know how you hash your email address will potentially know every password.
If you're looking to a password recovery system, you should instead use a Self-service password reset system.
The users says that he forgot the password
You send a unique key (that you store in your database) to this user by a secure mean (usually mail).
The user confirm that he forgot the password by giving you the unique key previously used. This way you're sure that the user is the owner.
You generate a totally random password that you store (in the hashed form) in your database and send it to the owner by the previously used secure mean.