/**
* starting mppe protocol.
*/
void
mppe_start(mppe *_this)
{
char buf[256];
strlcpy(buf, mppe_bits_to_string(_this->ppp->ccp.mppe_o_bits),
sizeof(buf));
mppe_log(_this, LOG_INFO, "logtype=Opened our=%s peer=%s", buf,
mppe_bits_to_string(_this->ppp->ccp.mppe_p_bits));
_this->ppp->mppe_started = 1;
_this->send.stateless =
((_this->ppp->ccp.mppe_o_bits & CCP_MPPE_STATELESS) != 0)? 1 : 0;
if ((_this->ppp->ccp.mppe_o_bits & CCP_MPPE_NT_40bit) != 0) {
_this->send.keylen = 8;
_this->send.keybits = 40;
} else if ((_this->ppp->ccp.mppe_o_bits & CCP_MPPE_NT_56bit) != 0) {
_this->send.keylen = 8;
_this->send.keybits = 56;
} else if ((_this->ppp->ccp.mppe_o_bits & CCP_MPPE_NT_128bit) != 0) {
_this->send.keylen = 16;
_this->send.keybits = 128;
}
_this->recv.stateless =
((_this->ppp->ccp.mppe_p_bits & CCP_MPPE_STATELESS) != 0)? 1 : 0;
if ((_this->ppp->ccp.mppe_p_bits & CCP_MPPE_NT_40bit) != 0) {
_this->recv.keylen = 8;
_this->recv.keybits = 40;
} else if ((_this->ppp->ccp.mppe_p_bits & CCP_MPPE_NT_56bit) != 0) {
_this->recv.keylen = 8;
_this->recv.keybits = 56;
} else if ((_this->ppp->ccp.mppe_p_bits & CCP_MPPE_NT_128bit) != 0) {
_this->recv.keylen = 16;
_this->recv.keybits = 128;
}
if (_this->send.keybits > 0) {
mppe_rc4_init(_this, &_this->send, 0);
GetNewKeyFromSHA(_this->send.master_key, _this->send.master_key,
_this->send.keylen, _this->send.session_key);
mppe_reduce_key(&_this->send);
mppe_rc4_setkey(_this, &_this->send);
}
if (_this->recv.keybits > 0) {
mppe_rc4_init(_this, &_this->recv, _this->recv.stateless);
GetNewKeyFromSHA(_this->recv.master_key, _this->recv.master_key,
_this->recv.keylen, _this->recv.session_key);
mppe_reduce_key(&_this->recv);
mppe_rc4_setkey(_this, &_this->recv);
}
}
static void
MPPEKeyChange(struct mppe_state *mp)
{
char InterimKey[MPPE_KEY_LEN];
RC4_KEY RC4Key;
GetNewKeyFromSHA(mp->mastkey, mp->sesskey, mp->keylen, InterimKey);
RC4_set_key(&RC4Key, mp->keylen, InterimKey);
RC4(&RC4Key, mp->keylen, InterimKey, mp->sesskey);
MPPEReduceSessionKey(mp);
}
static void
mppe_key_change(mppe *_mppe, mppe_rc4_t *_this)
{
u_char interim[16];
void *keychg;
keychg = rc4_create_ctx();
GetNewKeyFromSHA(_this->master_key, _this->session_key,
_this->keylen, interim);
rc4_key(keychg, _this->keylen, interim);
rc4(keychg, _this->keylen, interim, _this->session_key);
mppe_reduce_key(_this);
if (_this->old_session_keys) {
int idx = _this->coher_cnt % MPPE_NOLDKEY;
memcpy(_this->old_session_keys[idx],
_this->session_key, MPPE_KEYLEN);
}
free(keychg);
}
