In the following code there is a comparison of the password stored in
the database with the
password entered by the user. Since the salt is created by appending a
random number, how come it
matches with what is stored in the database?
def self.authenticate(name, password)
user = self.find_by_name(name)
if user
expected_password = encrypted_password(password, user.salt)
if user.hashed_password != expected_password
user = nil
end
end
user
create_new_salt
self.hashed_password = User.encrypted_password(self.password, self.salt)
end
private
def self.encrypted_password(password, salt)
string_to_hash = password + “wibble” + salt # ‘wibble’ makes it harder
to guess
Digest::SHA1.hexdigest(string_to_hash)
end
def create_new_salt
self.salt = self.object_id.to_s + rand.to_s
end
end
TIA.
On Sat, 14 Oct 2006 18:39:16 -0700 (PDT), Bala P. wrote:
In the following code there is a comparison of the password stored in the database with the
password entered by the user. Since the salt is created by appending a random number, how come it
matches with what is stored in the database?
The salt’s created only the first time it’s needed; after that, it’s
always
the same (note that it’s stored in the user’s record). So it’s “random”
to
anyone trying a dictionary attack, but perfectly deterministic to your
application.
Jay L.
On Oct 14, 2006, at 8:39 PM, Bala P. wrote:
In the following code there is a comparison of the password stored
in the database with the
password entered by the user. Since the salt is created by
appending a random number, how come it
matches with what is stored in the database?
The salt is stored in the user record when it is created.
Cheers
Dave
Bala P. wrote:
In the following code there is a comparison of the password stored in
the database with the
password entered by the user. Since the salt is created by appending a
random number, how come it
matches with what is stored in the database?
def self.authenticate(name, password)
user = self.find_by_name(name)
if user
expected_password = encrypted_password(password, user.salt)
if user.hashed_password != expected_password
user = nil
end
end
user
create_new_salt
self.hashed_password = User.encrypted_password(self.password, self.salt)
end
private
def self.encrypted_password(password, salt)
string_to_hash = password + “wibble” + salt # ‘wibble’ makes it harder
to guess
Digest::SHA1.hexdigest(string_to_hash)
end
def create_new_salt
self.salt = self.object_id.to_s + rand.to_s
end
end
TIA.
You can be more secure. Store in the database encrypted salt
def create_new_salt
self.salt = Digest::SHA1.hexdigest(self.object_id.to_s + rand.to_s)
end
and even more - do the same whith password before concatenate it with
salt.
and even more - use Digest::SHA1.hexdigest for password and salt
and Digest::SHA256.hexdigest for hashed_password ( require
‘digest/sha2’)