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SQL Server

Duplicate openssl dgst -md5 -sign myKey.pem something.txt | openssl enc -base64 -A

See more RSA Examples

Demonstrates how to duplicate the creation of an RSA signature produced by this OpenSSL command:
openssl dgst -md5 -sign myKey.pem something.txt | openssl enc -base64 -A

Chilkat SQL Server Downloads

SQL Server
-- Important: See this note about string length limitations for strings returned by sp_OAMethod calls.
--
CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    -- Important: Do not use nvarchar(max).  See the warning about using nvarchar(max).
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @success int
    SELECT @success = 0

    -- This example assumes the Chilkat API to have been previously unlocked.
    -- See Global Unlock Sample for sample code.

    DECLARE @pkey int
    EXEC @hr = sp_OACreate 'Chilkat.PrivateKey', @pkey OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    -- Load the private key from an RSA PEM file:
    EXEC sp_OAMethod @pkey, 'LoadPemFile', @success OUT, 'myKey.pem'

    DECLARE @rsa int
    EXEC @hr = sp_OACreate 'Chilkat.Rsa', @rsa OUT

    -- Import the private key into the RSA component:
    EXEC sp_OAMethod @rsa, 'UsePrivateKey', @success OUT, @pkey
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @rsa, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @pkey
        EXEC @hr = sp_OADestroy @rsa
        RETURN
      END

    -- OpenSSL uses BigEndian byte ordering:
    EXEC sp_OASetProperty @rsa, 'LittleEndian', 0

    -- The resulting signature will be a Base64 string:
    EXEC sp_OASetProperty @rsa, 'EncodingMode', 'base64'

    -- For simplicity, we're not loading
    -- the data to be signed from a file.  We are instead simply
    -- using a literal string value.  
    DECLARE @strData nvarchar(4000)
    SELECT @strData = 'This is the text to be signed.'

    -- Hash the input using MD5, and then sign the hash:
    -- Other valid hash algorithm choices are "md2" and "sha-1".
    DECLARE @base64Sig nvarchar(4000)
    EXEC sp_OAMethod @rsa, 'SignStringENC', @base64Sig OUT, @strData, 'md5'


    PRINT @base64Sig


    PRINT 'Success!'

    EXEC @hr = sp_OADestroy @pkey
    EXEC @hr = sp_OADestroy @rsa


END
GO