question: public boolean verifyClientEvidenceMessage ( BigInteger clientM1 ) throws CryptoException { if ( ( this . A == null ) || ( this . B == null ) || ( this . S == null ) ) { throw new CryptoException ( "Impossible to compute and verify M1: " + "some data are missing from the previous operations (A,B,S)" ) ; } BigInteger computedM1 = SRP6Util . calculateM1 ( digest , N , A , B , S ) ; if ( computedM1 . equals ( clientM1 ) ) { this . M1 = clientM1 ; return true ; } return false ; }
target:  Authenticates the received client evidence message M1 and saves it only if correct. To be called after calculating the secret S.