/**********************************************************************
* %FUNCTION: peer_find
* %ARGUMENTS:
* addr -- IP address of peer
* hostname -- AVP peer hostname
* %RETURNS:
* A pointer to the peer with given IP address, or NULL if not found.
* %DESCRIPTION:
* Searches peer hash table for specified peer.
***********************************************************************/
l2tp_peer *
l2tp_peer_find(struct sockaddr_in *addr, char const *peername)
{
void *cursor;
l2tp_peer *peer = NULL;
l2tp_peer *candidate = NULL;
char addr1_str[16], addr2_str[16];
for (candidate = hash_start(&all_peers, &cursor);
candidate ;
candidate = hash_next(&all_peers, &cursor)) {
unsigned long mask = candidate->mask_bits ?
htonl(0xFFFFFFFFUL << (32 - candidate->mask_bits)) : 0;
strcpy(addr1_str, inet_ntoa(addr->sin_addr));
strcpy(addr2_str, inet_ntoa(candidate->addr.sin_addr));
DBG(l2tp_db(DBG_TUNNEL, "l2tp_peer_find(%s) examining peer %s/%d\n",
addr1_str, addr2_str,
candidate->mask_bits));
if ((candidate->addr.sin_addr.s_addr & mask) ==
(addr->sin_addr.s_addr & mask)
&& (!peername ||
!(candidate->peername[0]) ||
!strcmp(peername,candidate->peername))) {
if (peer == NULL) {
peer = candidate;
} else {
if (peer->mask_bits < candidate->mask_bits)
peer = candidate;
}
}
}
strcpy(addr1_str, inet_ntoa(addr->sin_addr));
if (peer != NULL)
strcpy(addr2_str, inet_ntoa(peer->addr.sin_addr));
DBG(l2tp_db(DBG_TUNNEL, "l2tp_peer_find(%s) found %s/%d\n",
addr1_str,
peer == NULL ? "NULL" : addr2_str,
peer == NULL ? -1 : peer->mask_bits));
return peer;
}
/**********************************************************************
* %FUNCTION: session_free
* %ARGUMENTS:
* ses -- a session to free
* %RETURNS:
* Nothing
* %DESCRIPTION:
* Frees a session, closing down all resources associated with it.
***********************************************************************/
void
l2tp_session_free(l2tp_session *ses, char const *reason)
{
session_set_state(ses, SESSION_IDLE);
DBG(l2tp_db(DBG_SESSION, "session_free(%s) %s\n",
l2tp_debug_session_to_str(ses), reason));
if (ses->call_ops && ses->call_ops->close) {
ses->call_ops->close(ses, reason);
}
memset(ses, 0, sizeof(l2tp_session));
free(ses);
}
/**********************************************************************
* %FUNCTION: auth_gen_response
* %ARGUMENTS:
* msg_type -- message type
* secret -- secret to use
* challenge -- challenge received from peer
* chal_len -- length of challenge
* buf -- buffer in which to place 16-byte response
* %RETURNS:
* Nothing
* %DESCRIPTION:
* Computes a response for the challenge using "secret"
***********************************************************************/
void
l2tp_auth_gen_response(uint16_t msg_type,
char const *secret,
unsigned char const *challenge,
size_t chal_len,
unsigned char buf[16])
{
struct MD5Context ctx;
unsigned char id = (unsigned char) msg_type;
MD5Init(&ctx);
MD5Update(&ctx, &id, 1);
MD5Update(&ctx, (unsigned char *) secret, strlen(secret));
MD5Update(&ctx, challenge, chal_len);
MD5Final(buf, &ctx);
DBG(l2tp_db(DBG_AUTH, "auth_gen_response(secret=%s) -> %02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x\n", secret,
buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6], buf[7],
buf[8], buf[9], buf[10], buf[11], buf[12], buf[13], buf[14], buf[15]));
}
