'Adds a private key to the agent\'s collection of identities.  On
subsequent interactions, the private key can be accessed using only the
corresponding public key.'

def agentc_ADD_IDENTITY(self, data):

    (keyType, rest) = getNS(data)
    if (keyType == 'ssh-rsa'):
        nmp = 6
    elif (keyType == 'ssh-dss'):
        nmp = 5
    else:
        raise keys.BadKeyError(('unknown    blob    type:    %s' % keyType))
    rest = getMP(rest, nmp)[(-1)]
    (comment, rest) = getNS(rest)
    k = keys.Key.fromString(data, type='private_blob')
    self.factory.keys[k.blob()] = (k, comment)
    self.sendResponse(AGENT_SUCCESS, '')
