Changing user name and password in CouchDB _user database - passwords

I am using jquery.couch.js to do signup/login/logout to a CouchDB _users database in my Sproutcore application. Is anyone aware of a method for changing user _id and password?

As far as I know the user id cannot be changed but the password can.
The CouchDB documentation describes the process of changing a user password in detail, short:
Get the org.couchdb.user:<myuser> document
Add a password field with the plaintext password
Store the document back to the _users database
As soon as the document is in the database, the CouchDB rehashes the plaintext password using PBKDF2 (at least since CouchDB 1.3).

Unfortunately, there is no built-in API to do this. The best thing for now is to read the jquery.couch.js code for account creation and use the same code or algorithms to do account modification.
Specifically, you need to update the password_sha and salt values to change a password. To change a user name, you must make a new document, then delete the old document. Just keep the _id and name values in sync and you'll be okay.

Related

IBM Worklight. Is it possible to store user credentials securely and recover them without user interacton?

There is a common requirement of storing user credentials securely (user id / user password) in the App and use them automatically next time the App starts, but I'm not being able to figure out how to do this without user interaction.
Using JSON Store I need a password to encrypt the information, so if I store user credentials in the JSON Store I will need to ask to the user for the password used to encrypt the information.
A solution I figure out is to store the user id in a JSON Store without encryption and the password in a JSON Store encrypted with the user id as password. May be this solution provide a bit more security than not to encrypt anything but I think is not a complete solution.
As explained in the comments this is a really bad idea.
Is there any solution to store user credentials securely and recover them without user interaction?
You can use the Keychain API on iOS. Android doesn't seem to have an equivalent API.
The most complete solution I figure out is to store the user id in a JSON Store without encryption and the password in a JSON Store encrypted with the user id as password. May be this solution provide a bit more security than not to encrypt anything but I think is not a complete solution.
I would strongly advise against doing that, if you store the encryption key (the user id) in plain text, then the attacker can simply use that to get to the password.
Update (Aug 27, 2014)
You should consider:
Hashing - You could hash values you want to protect. These are one-way functions, so you can't get the password back once you hash it. However, you can verify that the user provided the correct password. For example: First login you store( hash(password) ) then on next logins you compare if hash(password_provided) == stored_password_hash. If it matches, the user provided the same password. You should also use a salt.
You could give the user the ability set a pin using some library like ABPadLockScreen (you could probably find or implement something similar for Android too). You can then use the pin as the PBKDF2 input to generate an encryption key (JSONStore will do this for you when you pass the pin as the password). I would advise in favor of letting users only try a small amount of incorrect pin numbers, especially if the pin is only numeric and short, that way they can't easily guess the pin by trying various combinations. The idea here is that a pin will be easier to remember and type than their password.
FYI - There's a Stack Exchange site similar to StackOverflow but for security questions here.

How can I make a CouchDB database readable for public while having set require_valid_user to true?

My goal is to be able to read one database without having to authenticate the user, authentication for editing this database should be required. All other databases should only be read/writeable for valid users. And I don't want having to set it for every database I create in the future, authentication required for read/write required should be the default.
I thought I could do this by setting require_valid_user to true, but now CouchDB always asks for username and password, so I need a way to exclude one database. This database should be readable for public and writeable for valid users then.
I get around this problem by authenticating all users through one single database (i.e. /login). That database is public, and contains a design document with an HTML file as an attachment. The user is served this file, fills out their credentials on a form, and I use jQuery.couch.js to authenticate and store a cookie in their browser. Once they've got a valid login, I inspect the userCtx object to check their role, and redirect them to the appropriate database.
It's a hack, but until CouchDB is able to serve a login page instead of a JSON error message whenever you're not logged into a database, it's the only reliable method I've found.
Make sure to protect your public login database with a validate_doc_update key in the design document, so nobody but admins can overwrite anything in it.
Hope this helps.

Is there a safe way to send a user their password in clear text via email?

If I understand correctly, the biggest problem with sending a password via email is that it requires the password to be stored in clear text in the database. If the DB is compromised, the attackers will gain access to all accounts.
Is there a workaround for this problem?
How can one make sending a user their password via email as safe as possible?
The simple answer is: don't. If you think your database is insecure, an email is far, far less.
If you mean that you want to send them their password when they register, then you could do that before you store it in the database.
If you mean after they have registered, the only option is to store in plaintext (again, don't do this) or make a new, random password and send them that. It is impossible to get their password from the hash, which is why it makes the password storage safer. The best option is to generate a new (temporary) password you send them, or a token giving them access to a password change system.
You may want to consider a good hashing algorithm like BCrypt that includes a salt.
I don't know if my suggestion is feasible for your scenario, but you should better keep the data hashed or encrypted and send password reset links instead of plain-text passwords.
The moment the password is in cleartext in the email, it is inherently insecure.
As such, there is no safe way to send a password in cleartext safely.
You should not be storing passwords in cleartext in your database - you should be using salted hashes. When the user enters their password, you hash it with the salt and compare to the stored hash.
When people forget their password, instead of sending passwords by email, you should send reset links backed up by expiring tokens. These would generate a temporary new password (that would expire within minutes).
You should be hashing all passwords in your database.
sha1($_POST['password'].$salt.$username);
In the case of a lost password
A user requests a password reset link, which contains a hash generated in the "user_meta" table. When the user recieves this link, the hash is compared to that in the database, and the user will be able to UPDATE their current password with a new password.
The PTXT of the password is never reveiled.
You only compare hashes.
Yes, there is a common workaround.
Assuming that you have your users in your database.
You send the "password reset link" containing some "key" information, like a guid. An example link is a form:
http://your.site.com/setpassword?id=5b070092-4be8-4f4d-9952-1b915837d10f
In your database you store the mapping between sent guids and emails.
When someone opens your link, you check your database and you can find out who asks for the page - because any valid guid maps to an email. You can then safely let the user change his/her password assuming their email is not compromised.
When it's about to store the password, you never store it in plain text, you always hash passwords, using additional random salt to make the dictionary attack more difficult when someone breaks into your database.
There is a workaround which is less secure than a password reset but works if it is a requirement that users are sent a password, not a reset link.
What you do is you generate a new password that contains sufficient randomness to be very hard to guess, but is also formatted in a way that it is easy for them to remember and read out (say over the phone).
Something like: xyz-xyz-xyz-nnnn where xyz is an easy-to-spell but uncommon word and nnnn is a four digit number.
Then set it up so that this is a temporary password that needs to be changed on first login.
Set the password using the same logic you would use to set a normal password, so that it is correctly salted and hashed, and then send the password plaintext via email, like so.
Dear FirstName LastName,
You requested we reset your password.
Your new password is:
insipid-mirth-nonplus-9174
You will be able to log into the system once using this password, then you will need to enter a new password.
Important Caveats
This system has some serious vulnerabilities which make it unsuitable for websites where data security is crucial. There are more than these, but these are the ones I know/can think of:
Unlike systems which use a password reset link, this system could be used to lock someone out of the system (assuming you use it as is) unless you either require someone to fill out identifiable information before issuing the password reset, or send a "are you sure you want to reset your password?" email first. This would entail them clicking on a link with a GUID that goes to the server; at that point they may as well be sent to the password reset form anyway.
Since the password is being sent plain text via email, there is a danger it can be intercepted and the password can be used. Although to be fair this is not that much different than the risk of sending a password reset link.
If you ignore the risks in step #1 and you don't use a sufficiently random way of generating passwords (say you use a word list of fewer than 1000 items), someone who has hacked into your server will be able to retrieve the salted password hash and then write an algorithm that generates all possible passwords and checks them against the hashed password. Not as much of a problem if you use a cryptographically complex hashing algorithm.
If you want to send password to user via Email in cleartext and want to store those password into database as hash or any other format . It will be possible.......
Just you will have to follow some simple way....
1 .you will have to take those password as variable which will send from user.
2. When you store database then just convert it as you wishes format.
3. But when you send those to user by mail , That time just sent those variable password...
I think it will be helpful to build your concept about WAY.......

login to any user account in application

I have a asp.net application which is using form authentication, as this application is going to be online and we are looking for a secret login page by which we can login to any user account with only his username.
Is that possible?
EDIT
Or if there is any way I can read password from sql server aspnet_Users table, If I can convert it into plain text and use a general method to login. That would work for me
You can't "convert" it back. All hash functions are one-way only so there is no way to get original value.
Edit: There are 'rainbow' tables, which is basically dictionary of text-hash mapping. But they won't help you, because passwords are also salted in default Membership implementation.

how to create a login module

i have to create a login module (The question is not language specific) but i am not sure how will i validate the user. Where and how will i store the passwords. Will i have to encrypt and decrypt my passwords and if yes what are the best suggested way to do them. Overall i need to know what all things i need to take care of for developing a login module where a user can login securely to access my site.
You don't need to decrypt your passwords in order to validate them, just one way encryption works fine for this. The idea is that when a user enters a password, you encrypt it the same way (using the same algorithm and "salt") and then compare with the encrypted one stored in your database. If they are equal, with a great probability it means it's the same original password. Thus you prevent anyone - the adminstrator or any attacker - from knowing the original passwords users use on your web site.
As for the rest, it's very simple, you have a table in your database which contains user logins, encrypted passwords, and possibly some profile information as well (full name, etc).
I usually use the following function to hash user passwords:
$password_hash = sha1(MY_SALT_1 . $login_name . MY_SALT_2 .
$password . MY_SALT_3);
where MY_SALT_* are arbitrary predefined strings, could be e.g. 'the dark', 'side of', 'the moon' (or actually the less related - the better).
Yes.Sure you need to encrypt users passwords.Because most of the users using the same password almost all sites.At that time they are not want to show the passwords to admin.And another reason is most of the time the site DB may be accessed not only by admin.Some other technical persons in the organization.So it is better to encrypt the password.SHA1 is the best way to make the encryption.
Where and how will i store the passwords.
I am not sure what you mean by this.Every one use the database for it like phpmyadmin.