How should I really save salts
I have done a lot of research on security, and password hashing, but there is one thing that there seems to be a lot of opinions about. How to save salts. I was hoping someone with expertise in this field could give a professional opinion on the matter. Should I store salts in the DB? In a separate file? Should they be in the same DB as the passwords?
Thanks for the help.
javascript hash
edited Nov 25 '18 at 20:25
Neil Lunn
98k23174184
asked Nov 25 '18 at 19:48
Brandon FederBrandon Feder
62
add a comment |
I have done a lot of research on security, and password hashing, but there is one thing that there seems to be a lot of opinions about. How to save salts. I was hoping someone with expertise in this field could give a professional opinion on the matter. Should I store salts in the DB? In a separate file? Should they be in the same DB as the passwords?
Thanks for the help.
javascript hash
edited Nov 25 '18 at 20:25
Neil Lunn
98k23174184
asked Nov 25 '18 at 19:48
Brandon FederBrandon Feder
62
The first rule to password security is, don’t roll your own encryption algorithm. Use a tried and true library like bcrypt.
– Nate
Nov 25 '18 at 19:53
1
You might want to look into bcrypt, which as far as I know, uses random salts and manage them in a way I can't actually explain it. But yes, it does save these salts for you without having to export it to files, etc.
– ionizer
Nov 25 '18 at 19:53
add a comment |
I have done a lot of research on security, and password hashing, but there is one thing that there seems to be a lot of opinions about. How to save salts. I was hoping someone with expertise in this field could give a professional opinion on the matter. Should I store salts in the DB? In a separate file? Should they be in the same DB as the passwords?
Thanks for the help.
javascript hash
edited Nov 25 '18 at 20:25
Neil Lunn
98k23174184
asked Nov 25 '18 at 19:48
Brandon FederBrandon Feder
62
I have done a lot of research on security, and password hashing, but there is one thing that there seems to be a lot of opinions about. How to save salts. I was hoping someone with expertise in this field could give a professional opinion on the matter. Should I store salts in the DB? In a separate file? Should they be in the same DB as the passwords?
Thanks for the help.
javascript hash
javascript hash
edited Nov 25 '18 at 20:25
Neil Lunn
98k23174184
asked Nov 25 '18 at 19:48
Brandon FederBrandon Feder
62
edited Nov 25 '18 at 20:25
Neil Lunn
98k23174184
asked Nov 25 '18 at 19:48
Brandon FederBrandon Feder
62
edited Nov 25 '18 at 20:25
Neil Lunn
98k23174184
edited Nov 25 '18 at 20:25
Neil Lunn
98k23174184
edited Nov 25 '18 at 20:25
Neil Lunn
98k23174184
98k23174184
asked Nov 25 '18 at 19:48
Brandon FederBrandon Feder
62
asked Nov 25 '18 at 19:48
Brandon FederBrandon Feder
62
asked Nov 25 '18 at 19:48
Brandon FederBrandon Feder
62
62
The first rule to password security is, don’t roll your own encryption algorithm. Use a tried and true library like bcrypt.
– Nate
Nov 25 '18 at 19:53
1
You might want to look into bcrypt, which as far as I know, uses random salts and manage them in a way I can't actually explain it. But yes, it does save these salts for you without having to export it to files, etc.
– ionizer
Nov 25 '18 at 19:53
add a comment |
The first rule to password security is, don’t roll your own encryption algorithm. Use a tried and true library like bcrypt.
– Nate
Nov 25 '18 at 19:53
1
You might want to look into bcrypt, which as far as I know, uses random salts and manage them in a way I can't actually explain it. But yes, it does save these salts for you without having to export it to files, etc.
– ionizer
Nov 25 '18 at 19:53
The first rule to password security is, don’t roll your own encryption algorithm. Use a tried and true library like bcrypt.
– Nate
Nov 25 '18 at 19:53
The first rule to password security is, don’t roll your own encryption algorithm. Use a tried and true library like bcrypt.
– Nate
Nov 25 '18 at 19:53
1
1
You might want to look into bcrypt, which as far as I know, uses random salts and manage them in a way I can't actually explain it. But yes, it does save these salts for you without having to export it to files, etc.
– ionizer
Nov 25 '18 at 19:53
You might want to look into bcrypt, which as far as I know, uses random salts and manage them in a way I can't actually explain it. But yes, it does save these salts for you without having to export it to files, etc.
– ionizer
Nov 25 '18 at 19:53
add a comment |
2 Answers
2
active
oldest
votes
@ManyelReyes has the correct answer, and here is why:
Salts protect against rainbow tables. A rainbow table is a precalculated list of the hashes of common passwords.
So, if you just saved the password hash for someone and they used a common password, then the attacker could find it in the rainbow table and know the password.
By adding something random to every password you make rainbow tables not work. They work because they can be precalculated. When you add the salt into the user's password the rainbow table can't be precalcuated, since the salt is random. If you used the same salt for every user they could make a rainbow table using that salt.
Since it does not change the security provided by salts to have the attacker know that you are using them and what the salt is, you can store the salt in the clear in the user table. (I've also appended them to the hash result, then I don't need an extra column, as long as the hash is always the same length.)
answered Nov 25 '18 at 20:24
HoganHogan
54.9k866102
add a comment |
There should be one random salt per user (Do not use the same salt to every user). Every time a user creates an account or changes their password, the password should be hashed using a new random salt. The salt should be stored in the user account table alongside the hash.
Add the salt to the password and hash it with a standard password hashing function. Save both the salt and the hash in the user's database record.
To validate a password, retrieve the user's salt and hash from the database. Add the salt to the given password and hash it using the same hash function.
Compare the hash of the given password with the hash from the database. If they match, the password is correct. Otherwise, the password is incorrect.
More info here
answered Nov 25 '18 at 20:15
Manuel ReyesManuel Reyes
616
How do you know which user you should get the hash for?
– Brandon Feder
Nov 28 '18 at 23:36
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
@ManyelReyes has the correct answer, and here is why:
Salts protect against rainbow tables. A rainbow table is a precalculated list of the hashes of common passwords.
So, if you just saved the password hash for someone and they used a common password, then the attacker could find it in the rainbow table and know the password.
By adding something random to every password you make rainbow tables not work. They work because they can be precalculated. When you add the salt into the user's password the rainbow table can't be precalcuated, since the salt is random. If you used the same salt for every user they could make a rainbow table using that salt.
Since it does not change the security provided by salts to have the attacker know that you are using them and what the salt is, you can store the salt in the clear in the user table. (I've also appended them to the hash result, then I don't need an extra column, as long as the hash is always the same length.)
answered Nov 25 '18 at 20:24
HoganHogan
54.9k866102
add a comment |
@ManyelReyes has the correct answer, and here is why:
Salts protect against rainbow tables. A rainbow table is a precalculated list of the hashes of common passwords.
So, if you just saved the password hash for someone and they used a common password, then the attacker could find it in the rainbow table and know the password.
By adding something random to every password you make rainbow tables not work. They work because they can be precalculated. When you add the salt into the user's password the rainbow table can't be precalcuated, since the salt is random. If you used the same salt for every user they could make a rainbow table using that salt.
Since it does not change the security provided by salts to have the attacker know that you are using them and what the salt is, you can store the salt in the clear in the user table. (I've also appended them to the hash result, then I don't need an extra column, as long as the hash is always the same length.)
answered Nov 25 '18 at 20:24
HoganHogan
54.9k866102
add a comment |
@ManyelReyes has the correct answer, and here is why:
Salts protect against rainbow tables. A rainbow table is a precalculated list of the hashes of common passwords.
So, if you just saved the password hash for someone and they used a common password, then the attacker could find it in the rainbow table and know the password.
By adding something random to every password you make rainbow tables not work. They work because they can be precalculated. When you add the salt into the user's password the rainbow table can't be precalcuated, since the salt is random. If you used the same salt for every user they could make a rainbow table using that salt.
Since it does not change the security provided by salts to have the attacker know that you are using them and what the salt is, you can store the salt in the clear in the user table. (I've also appended them to the hash result, then I don't need an extra column, as long as the hash is always the same length.)
answered Nov 25 '18 at 20:24
HoganHogan
54.9k866102
@ManyelReyes has the correct answer, and here is why:
Salts protect against rainbow tables. A rainbow table is a precalculated list of the hashes of common passwords.
So, if you just saved the password hash for someone and they used a common password, then the attacker could find it in the rainbow table and know the password.
By adding something random to every password you make rainbow tables not work. They work because they can be precalculated. When you add the salt into the user's password the rainbow table can't be precalcuated, since the salt is random. If you used the same salt for every user they could make a rainbow table using that salt.
Since it does not change the security provided by salts to have the attacker know that you are using them and what the salt is, you can store the salt in the clear in the user table. (I've also appended them to the hash result, then I don't need an extra column, as long as the hash is always the same length.)
answered Nov 25 '18 at 20:24
HoganHogan
54.9k866102
answered Nov 25 '18 at 20:24
HoganHogan
54.9k866102
answered Nov 25 '18 at 20:24
HoganHogan
54.9k866102
answered Nov 25 '18 at 20:24
HoganHogan
54.9k866102
54.9k866102
add a comment |
add a comment |
There should be one random salt per user (Do not use the same salt to every user). Every time a user creates an account or changes their password, the password should be hashed using a new random salt. The salt should be stored in the user account table alongside the hash.
Add the salt to the password and hash it with a standard password hashing function. Save both the salt and the hash in the user's database record.
To validate a password, retrieve the user's salt and hash from the database. Add the salt to the given password and hash it using the same hash function.
Compare the hash of the given password with the hash from the database. If they match, the password is correct. Otherwise, the password is incorrect.
More info here
answered Nov 25 '18 at 20:15
Manuel ReyesManuel Reyes
616
How do you know which user you should get the hash for?
– Brandon Feder
Nov 28 '18 at 23:36
add a comment |
There should be one random salt per user (Do not use the same salt to every user). Every time a user creates an account or changes their password, the password should be hashed using a new random salt. The salt should be stored in the user account table alongside the hash.
Add the salt to the password and hash it with a standard password hashing function. Save both the salt and the hash in the user's database record.
To validate a password, retrieve the user's salt and hash from the database. Add the salt to the given password and hash it using the same hash function.
Compare the hash of the given password with the hash from the database. If they match, the password is correct. Otherwise, the password is incorrect.
More info here
answered Nov 25 '18 at 20:15
Manuel ReyesManuel Reyes
616
How do you know which user you should get the hash for?
– Brandon Feder
Nov 28 '18 at 23:36
add a comment |
There should be one random salt per user (Do not use the same salt to every user). Every time a user creates an account or changes their password, the password should be hashed using a new random salt. The salt should be stored in the user account table alongside the hash.
Add the salt to the password and hash it with a standard password hashing function. Save both the salt and the hash in the user's database record.
To validate a password, retrieve the user's salt and hash from the database. Add the salt to the given password and hash it using the same hash function.
Compare the hash of the given password with the hash from the database. If they match, the password is correct. Otherwise, the password is incorrect.
More info here
answered Nov 25 '18 at 20:15
Manuel ReyesManuel Reyes
616
There should be one random salt per user (Do not use the same salt to every user). Every time a user creates an account or changes their password, the password should be hashed using a new random salt. The salt should be stored in the user account table alongside the hash.
Add the salt to the password and hash it with a standard password hashing function. Save both the salt and the hash in the user's database record.
To validate a password, retrieve the user's salt and hash from the database. Add the salt to the given password and hash it using the same hash function.
Compare the hash of the given password with the hash from the database. If they match, the password is correct. Otherwise, the password is incorrect.
More info here
answered Nov 25 '18 at 20:15
Manuel ReyesManuel Reyes
616
answered Nov 25 '18 at 20:15
Manuel ReyesManuel Reyes
616
answered Nov 25 '18 at 20:15
Manuel ReyesManuel Reyes
616
answered Nov 25 '18 at 20:15
Manuel ReyesManuel Reyes
616
616
How do you know which user you should get the hash for?
– Brandon Feder
Nov 28 '18 at 23:36
add a comment |
How do you know which user you should get the hash for?
– Brandon Feder
Nov 28 '18 at 23:36
How do you know which user you should get the hash for?
– Brandon Feder
Nov 28 '18 at 23:36
How do you know which user you should get the hash for?
– Brandon Feder
Nov 28 '18 at 23:36
add a comment |
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The first rule to password security is, don’t roll your own encryption algorithm. Use a tried and true library like bcrypt.
– Nate
Nov 25 '18 at 19:53
1
You might want to look into bcrypt, which as far as I know, uses random salts and manage them in a way I can't actually explain it. But yes, it does save these salts for you without having to export it to files, etc.
– ionizer
Nov 25 '18 at 19:53