What is IV and salt in encryption?
A salt is used so that the same password does not always generate the same key; however, because the recipient must be able to generate the correct key, the salt must be transmitted along with the encrypted data. An IV is required if you are using AES in certain block cipher modes, like CBC.
Salt is necessary to prevent pre-computation attacks. An IV (or nonce with counter modes) makes the same plain text produce different cipher texts. The prevents an attacker from exploiting patterns in the plain text to garner information from a set of encrypted messages.
An initialization vector (IV) is an arbitrary number that can be used along with a secret key for data encryption. This number, also called a nonce, is employed only one time in any session.
A cryptographic salt is made up of random bits added to each password instance before its hashing. Salts create unique passwords even in the instance of two users choosing the same passwords. Salts help us mitigate hash table attacks by forcing attackers to re-compute them using the salts for each user.
Yes, you must provide the same IV for encryption and decryption.
IV usually does not need to be secret, However, in most cases, it is important that an initialization vector is never reused under the same key. Wikipedia: An initialization vector has different security requirements than a key, so the IV usually does not need to be secret.
AES is just a cipher, and you can use an IV with the text you are encrypting. With symmetric encryption, the salt is used for the key/secret that you encrypt with, as you can see above. In the real world you will have to deal with distributed systems, shared keys and salts across the cluster, etc, etc.
GenerateKey() replaces the current key with a new random one (of size aes. KeySize). aes. GenerateIV() replaces the current IV with a new random one (of the block size, which is always 16 bytes for AES).
Description. Salt-key executes simple management of Salt server public keys used for authentication. On initial connection, a Salt minion sends its public key to the Salt master. This key must be accepted using the salt-key command on the Salt master.
To generate the IV, we use the SecureRandom class. The block size required depends on the AES encryption block size. For the default block size of 128 bits, we need an initialization vector of 16 bytes. From the initialization vector, we create an IvParameterSpec which is required when creating the Cipher.
Why IV should be random?
The IV should be random and only used once, otherwise it may allow people to decrypt other cipher texts which used the same key.
A common way to save the IV is to prepend it to the encrypted text. Therefore just write it to your memoryStream when encrypting. Then you can read it upon decryption. Side note: AesCryptoServiceProvider has a predefined method called GenerateIV() .
Hashing is a one-way process that converts a password to ciphertext using hash algorithms. A hashed password cannot be decrypted, but a hacker can try to reverse engineer it. Password salting adds random characters before or after a password prior to hashing to obfuscate the actual password.
Every salt should ideally have a long salt value of at least the same length as the output of the hash. If the output of the hash function used is 256 bits or 32 bytes, the length of the salt value should at least be 32 bytes.
The key point is that if you ever reuse an IV, you open yourself up to cryptographic attacks that are easier to execute than those when you use a different IV every time. So, for every sequence where you need to start encrypting again, you need a new, unique IV.
The IV should be stored in the database, together with the encrypted data (either concatenated in the same field, or in a separate field in the same row). This can be stored as plaintext, there is no value in its secrecy.
In cipher-block chaining mode (CBC mode), the IV need not be secret, but must be unpredictable (In particular, for any given plaintext, it must not be possible to predict the IV that will be associated to the plaintext in advance of the generation of the IV.) at encryption time.
The IV is public information, it's totally fine to send it over the network. However, you should use a cryptographically secure random for every single encryption, especially if you are using CBC mode.
The IV's purpose is to ensure same plaintexts encrypt to different ciphertexts. When an adversary learns the IV after the plaintext has been encrypted, no harm is done, since it has already served its purpose. The IV can be made public after encryption, without impacting the security of the system.
An IV fluid drip involves a small tube called a catheter and a saline-based electrolyte solution that contains your selected vitamins and nutrients. An IV drip delivers these essential nutrients and fluids directly into your bloodstream, bypassing your digestive tract.
What is salt stored in?
Salt should be stored in an airtight container in a cool, dry, dark location. Salt can be purchased in bulk and repackaged for long term storage in smaller containers. Oxygen absorbers are not recommended when packaging salt for long term storage.
The size of each block is usually measured in bits. AES, for example, is 128 bits long. Meaning, AES will operate on 128 bits of plaintext to produce 128 bits of ciphertext. Like almost all modern encryption algorithms, AES requires the use of secret keys during the encryption and decrypt processes.
An initialization vector (or IV) are used to ensure that the same value encrypted multiple times, even with the same secret key, will not always result in the same encrypted value. This is an added security layer.
Whenever you create a new instance of one of the managed symmetric cryptographic classes using the parameterless Create() method, a new key and IV are automatically created. Anyone that you allow to decrypt your data must possess the same key and IV and use the same algorithm.
In Cipher Block Chaining (CBC) mode, an initialization vector (IV) is added to the first block of plaintext before encryption and the resultant ciphertext is added to the next block of plaintext before encryption, and so on. Decryption is the reverse process.
Basically a key is used for encrypting and decrypting while a salt is used together with the hashing to make it even more secure.
salt-api is a modular interface on top of Salt that can provide a variety of entry points into a running Salt system. It can start and manage multiple interfaces allowing a REST API to coexist with XMLRPC or even a Websocket API.
Ensuring that your passwords and data are safe is a top priority. Hashing and salting of passwords and cryptographic hash functions ensure the highest level of protection. By adding salt to your password, you can effectively thwart even the strongest password attacks.
Hashing is a one-way process that converts a password to ciphertext using hash algorithms. A hashed password cannot be decrypted, but a hacker can try to reverse engineer it. Password salting adds random characters before or after a password prior to hashing to obfuscate the actual password.
A salt and an initialization vector are mostly the same thing in the following sense: they are public data, which should be generated anew for each instance (each hashed password, each encrypted message).
Can salted passwords be cracked?
As you can see from the above example it is possible to crack passwords that use salts. It just takes much longer and requires more processing time. Hashed passwords that use salts are what most modern authentication systems use.
An initialization vector is used to avoid repetition during the data encryption process, making it impossible for hackers who use dictionary attack to decrypt the exchanged encrypted message by discovering a pattern.
What is password salting? Password salting is a technique to protect passwords stored in databases by adding a string of 32 or more characters and then hashing them. Salting prevents hackers who breach an enterprise environment from reverse-engineering passwords and stealing them from the database.
The salt value is generated at random and can be any length; in this case the salt value is 8 bytes long. The salt value is appended to the plaintext password and then the result is hashed, which is referred to as the hashed value. Both the salt value and hashed value are stored.
What is Salting? Salting is a concept that typically pertains to password hashing. Essentially, it's a unique value that can be added to the end of the password to create a different hash value. This adds a layer of security to the hashing process, specifically against brute force attacks.
IV and nonce are often used interchangeably. Essentially though, an IV is a nonce with an additional requirement: it must be selected in a non-predictable way. This would eliminate all sequential nonces, an IV must be random.
i.e. A salt is simply added to make a common password uncommon. So hacker can find this rainbow table, to avoid this problem we have to store hash with the combination of password and salt. A Nonce (Number used only once) does not need to be secret or random, but it must not be reused with the same key.
The nonce on the whole has to be unique, but the salt can remain fixed for the lifetime of the key; the counter ensures that the nonce is always unique. In such a nonce, the random part is said to be a “salt.” Generally, it's good to have four or more bytes of salt in a nonce.
Salting is simply the addition of a unique, random string of characters known only to the site to each password before it is hashed, typically this “salt” is placed in front of each password. The salt value needs to be stored by the site, which means sometimes sites use the same salt for every password.
Ensuring that your passwords and data are safe is a top priority. Hashing and salting of passwords and cryptographic hash functions ensure the highest level of protection. By adding salt to your password, you can effectively thwart even the strongest password attacks.
How long should a password salt be?
Every salt should ideally have a long salt value of at least the same length as the output of the hash. If the output of the hash function used is 256 bits or 32 bytes, the length of the salt value should at least be 32 bytes.
An initialization vector (or IV) are used to ensure that the same value encrypted multiple times, even with the same secret key, will not always result in the same encrypted value. This is an added security layer.
The IV should be random and only used once, otherwise it may allow people to decrypt other cipher texts which used the same key.
The key point is that if you ever reuse an IV, you open yourself up to cryptographic attacks that are easier to execute than those when you use a different IV every time. So, for every sequence where you need to start encrypting again, you need a new, unique IV.
