implement Cipher; include "sys.m"; include "keyring.m";	kr: Keyring;	DESstate: import kr; include "sshio.m"; Cipherstate: adt{	enc: array of ref DESstate;	dec: array of ref DESstate;}; cs: ref Cipherstate; id(): int{	return SSH_CIPHER_3DES;} init(key: array of byte, nil: int){	kr = load Keyring Keyring->PATH;	cs = ref Cipherstate(array[3] of ref DESstate, array[3] of ref DESstate);	for(i := 0; i < 3; i++){		cs.enc[i] = kr->dessetup(key[i*8:], nil);		cs.dec[i] = kr->dessetup(key[i*8:], nil);	}} encrypt(buf: array of byte, nbuf: int){	kr->descbc(cs.enc[0], buf, nbuf, Keyring->Encrypt);	kr->descbc(cs.enc[1], buf, nbuf, Keyring->Decrypt);	kr->descbc(cs.enc[2], buf, nbuf, Keyring->Encrypt);} decrypt(buf: array of byte, nbuf: int){	kr->descbc(cs.dec[2], buf, nbuf, Keyring->Decrypt);	kr->descbc(cs.dec[1], buf, nbuf, Keyring->Encrypt);	kr->descbc(cs.dec[0], buf, nbuf, Keyring->Decrypt);}