static bool_t
is_conflicting_ssn( session_t *ssn )
{
if ((g_topo_session) && (g_topo_session->ssn_is_valid==TRUE) && /* if there already IS a topo-session, */
(ssn != g_topo_session) && /* and this is not the same session, */
(ssn->ssn_TypeOfSvc == ToS_TopologyDiscovery) && /* and this IS a topo-ssn Discover, */
/* and the real-addresses don't match, */
!(ETHERADDR_EQUALS(&ssn->ssn_mapper_real, &g_topo_session->ssn_mapper_real)))
{ /* then this is a conflicting Discover */
return TRUE;
}
return FALSE;
}
/* This function locates an existing session that is associated with the passed-in address */
static session_t *
find_session(etheraddr_t *this_addr)
{
session_t *ssn = &g_sessions[0];
int i;
for (i=0; i < MAX_NUM_SESSIONS; ssn++, i++)
{
if ( (ssn->ssn_is_valid) && (ETHERADDR_EQUALS(&ssn->ssn_mapper_real, this_addr)) )
{
DEBUG({printf("find_session returning session %d @ %X\n",i,(uint)ssn);})
return ssn;
}
static bool_t
is_acking_me(void)
{
etheraddr_t *p = (etheraddr_t*)(g_discover_hdr + 1);
etheraddr_t *limit = (etheraddr_t*)(((char*)g_ethernet_hdr) + g_rcvd_pkt_len);
uint16_t gen = ntohs(g_discover_hdr->mh_gen);
uint16_t numstations = ntohs(g_discover_hdr->mh_numstations);
bool_t acking = FALSE;
int i;
if (g_this_event.isAckingMe == TRUE) return TRUE;
IF_TRACED(TRC_PACKET)
dbgprintf("gen=%d, numsta=%d, stations=[", gen, numstations);
END_TRACE
/* parse seenlist, and decide if we are acked in this frame */
for (i=0; p+1 <= limit && i<numstations; i++, p++)
{
IF_TRACED(TRC_PACKET)
dbgprintf(ETHERADDR_FMT " ", ETHERADDR_PRINT(p));
END_TRACE
if (ETHERADDR_EQUALS(p, &g_hwaddr))
{
acking = TRUE;
/* we could break out early, but we also want to test the
* numstations count is accurate so we loop over all the
* acked addresses */
}
}
IF_TRACED(TRC_PACKET)
dbgprintf("]\n");
END_TRACE
if (i != numstations)
warn("rx_discover: truncated frame: ended at station %d, "
"but numstations claimed %d\n", i, numstations);
return acking;
}
static uint
validate_emit()
{
topo_emit_header_t *emit; /* pointer to emit header in g_rxbuf */
topo_emitee_desc_t *ed, *first_desc, *limit;
uint16_t numdescs;
int i;
/* Parse the Emit */
g_totalPause = 0;
g_neededPackets = 0;
g_neededBytes = 0;
if (g_rcvd_pkt_len < sizeof(topo_ether_header_t) + sizeof(topo_base_header_t) +
sizeof(topo_emit_header_t))
{
warn("validate_emit: frame with truncated Emit header (len=%d src="
ETHERADDR_FMT " dst=" ETHERADDR_FMT "); ignoring\n",
g_rcvd_pkt_len, ETHERADDR_PRINT(&g_ethernet_hdr->eh_src), ETHERADDR_PRINT(&g_ethernet_hdr->eh_dst));
g_this_event.evtType = evtInvalidPacket;
return INVALID_PACKET;
}
emit = (topo_emit_header_t*)(g_base_hdr + 1); // base the emit header in g_rxbuf
numdescs = ntohs(emit->eh_numdescs);
limit = (topo_emitee_desc_t*)(((uint8_t*)g_ethernet_hdr) + g_rcvd_pkt_len);
/* check the emitee_descs are asking for reasonable transmissions */
first_desc = (topo_emitee_desc_t*)(emit + 1);
IF_TRACED(TRC_PACKET)
dbgprintf("numdescs=%d EmiteeDescs=[", numdescs);
END_TRACE
for (i=0, ed=first_desc; ed+1 <= limit && i < numdescs; ed++, i++)
{
IF_TRACED(TRC_PACKET)
dbgprintf("{%s: %dms " ETHERADDR_FMT " -> " ETHERADDR_FMT "} ",
ed_type2name(ed->ed_type), ed->ed_pause,
ETHERADDR_PRINT(&ed->ed_src), ETHERADDR_PRINT(&ed->ed_dst));
END_TRACE
g_totalPause += ed->ed_pause;
if (ed->ed_type != 0x00 && ed->ed_type != 0x01)
{
warn("validate_emit: emitee_desc from " ETHERADDR_FMT " with unknown type=%d; "
"ignoring whole Emit request\n",
ETHERADDR_PRINT(&g_ethernet_hdr->eh_src), ed->ed_type);
g_this_event.evtType = evtInvalidPacket;
return INVALID_PACKET;
}
if (!ETHERADDR_EQUALS(&ed->ed_src, &g_hwaddr) &&
!TOPO_ETHERADDR_OUI(&ed->ed_src))
{
warn("validate_emit: emitee_desc with src=" ETHERADDR_FMT " is invalid; "
"ignoring whole Emit request\n",
ETHERADDR_PRINT(&ed->ed_src));
g_this_event.evtType = evtInvalidPacket;
return INVALID_PACKET;
}
if (ETHERADDR_IS_MCAST(&ed->ed_dst))
{
warn("validate_emit: emitee_desc with dst=" ETHERADDR_FMT " is invalid; "
"ignoring whole Emit request\n",
ETHERADDR_PRINT(&ed->ed_dst));
g_this_event.evtType = evtInvalidPacket;
return INVALID_PACKET;
}
g_neededPackets++;
g_neededBytes += sizeof(topo_ether_header_t) + sizeof(topo_base_header_t);
}
IF_TRACED(TRC_PACKET)
dbgprintf("]");
if (i != numdescs)
dbgprintf(" (numdescs too big!)");
dbgprintf("\n");
END_TRACE
if (g_totalPause > TOPO_TOTALPAUSE_MAX)
{
warn("validate_emit: Emit contains emitee_descs with total pausetime %ums > %ums; "
"ignoring whole Emit request\n",
g_totalPause, TOPO_TOTALPAUSE_MAX);
g_this_event.evtType = evtInvalidPacket;
return INVALID_PACKET;
}
if (i != numdescs)
{
warn("validate_emit: numdescs=%d but only %d descs in frame\n", numdescs, i);
numdescs = i;
}
/* will we need to send an ACK or Flat too? */
if (g_sequencenum != 0)
{
g_neededPackets++;
g_neededBytes += sizeof(topo_ether_header_t) + sizeof(topo_base_header_t);
}
/* emitee_descs look ok; pass them up to state machine */
g_this_event.numDescrs = numdescs;
g_this_event.evtType = evtEmitRcvd;
return VALID_PACKET;
}
