Generate Asymmetric Key Pair C

Yes, it is possible to deterministically generate public/private RSA key pairs from passphrases. For even passable security, the passphrase must be processed by a key-stretching function, such as Scrypt (or the better known but less recommendable PBKDF2), and salt (at least, user id) must enter the key-stretching function; the output can then be used as the seed material for the RSA key.

Asymmetric Key Encryption Example
Generate Asymmetric Key Pair Code
Asymmetric Key Algorithm
Generate Asymmetric Key Pair C Example
Asymmetric Key Example
Generate Asymmetric Key Pair C#

Introduction

A Strong Name File (SNF) can be used to 'sign' .NET assemblies. I put the word 'sign' in quotes, because there is no authentication mechanism provided, so all the signature really can tell you is if two different assemblies are coming from the same source. But that is the main purpose of SNFs anyway: They provide a way to generate a unique identifier for an assembly or a specific version of an assembly, a strong name.

An SNF contains just the public and the private key of an asymmetric key pair. There is no additional information stored in the file. SQL Server can take that information and create an asymmetric key in a database from it.

Asymmetric Key Encryption Example

How to Generate Unique Public and Private Key via RSA. Ask Question Asked 10 years, 8 months ago. Whenever a manager leaves the company I want to be able to generate new public and private keys (and re-encrypt all currently stored CC numbers with the new public key). RSA Key pair Exception on importing the private key.
Symmetric keys are good for encrypting large amounts of data, whereas asymmetric keys are better for small chunks. If two parties have their own key set, a typical scenario is to use asymmetric keys to securely exchange symmetric keys between two parties, and then use symmetric keys from then on to securely exchange large amounts of data.

A Strong (Name) Example

Creating an asymmetric key pair from an SNF involves the CREATE ASYMMETRIC KEY statement using the FROM FILE clause like this:

This will create an asymmetric key in the current database from that SNF:

The SNF in the above example does not have a path specified. If you execute the statement like that, the SNF has to exist in SQL Servers default database directory. However, you can also specify a fully qualified path like this:

The now specified path is not the only change in this statement. Additionally the ENCRYPTION BY PASSWORD clause is missing. As it is the case with the normal CREATE ASYMMETRIC KEY statement, that means that the private key is going to be encrypted with the database master key.

The SN Tool

Strong Name Files can be created with Microsoft's sn.exe tool. It for example comes bundled with Visual Studio. The exact syntax of how to use it you can look up following the above link. However, one parameter (-k) allows you to specify the key length. While you can specify any key length between 384 and 16384 bits (in increments of 8 bits), SQL Server can only import SNFs that were created with a key length of either 512, 1024 or 2048 bits.