Configuring MACs

The MAC (Message Authentication Code) algorithm(s) used for data integrity verification can be selected in the sshd2_config file:

MACs                hmac-sha1,hmac-md5

The system will attempt to use the different HMAC algorithms in the sequence they are specified on the line. The supported MAC names are the following:

`hmac-md5`	`hmac-sha2-256`	`hmac-sha384@ssh.com`
`hmac-md5-96`	`hmac-sha256-2@ssh.com`	`hmac-sha2-512`
`hmac-sha1`	`hmac-sha224@ssh.com`	`hmac-sha512@ssh.com`
`hmac-sha1-96`	`hmac-sha256@ssh.com`

Special values for this option are the following:

Any: includes all supported MACs plus none.
AnyStd: includes MACs from the IETF SSH standards (hmac-md5, hmac-md5-96, hmac-sha1, hmac-sha1-96, hmac-sha2-256, hmac-sha2-512) and none.
none: means that no cryptographic data integrity method is used.
AnyMac: the same as Any but excludes none.
AnyStdMac: the same as AnyStd but exludes none.

The default MAC algorithms are: hmac-sha1, hmac-sha1-96, hmac-sha2-256, hmac-sha256-2@ssh.com, hmac-sha224@ssh.com, hmac-sha256@ssh.com, hmac-sha384@ssh.com, hmac-sha2-512, and hmac-sha512@ssh.com.