-
Notifications
You must be signed in to change notification settings - Fork 390
/
pkt_handler.cc
1132 lines (963 loc) · 35.4 KB
/
pkt_handler.cc
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
* Copyright (c) 2013 Juniper Networks, Inc. All rights reserved.
*/
#include "base/os.h"
#include <sys/types.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <netinet/ip6.h>
#include <netinet/icmp6.h>
#include "cmn/agent_cmn.h"
#include "net/address_util.h"
#include "oper/ecmp_load_balance.h"
#include "oper/interface_common.h"
#include "oper/nexthop.h"
#include "oper/route_common.h"
#include "oper/vrf.h"
#include "oper/tunnel_nh.h"
#include "pkt/control_interface.h"
#include "pkt/pkt_handler.h"
#include "pkt/proto.h"
#include "pkt/flow_table.h"
#include "pkt/flow_proto.h"
#include "pkt/pkt_types.h"
#include "pkt/pkt_init.h"
#include "cmn/agent_stats.h"
#include "pkt/packet_buffer.h"
#include "vr_types.h"
#include "vr_defs.h"
#include "vr_mpls.h"
#define PKT_TRACE(obj, arg) \
do { \
std::ostringstream _str; \
_str << arg; \
Pkt##obj::TraceMsg(PacketTraceBuf, __FILE__, __LINE__, _str.str()); \
} while (false) \
const std::size_t PktTrace::kPktMaxTraceSize;
////////////////////////////////////////////////////////////////////////////////
PktHandler::PktHandler(Agent *agent, PktModule *pkt_module) :
stats_(), agent_(agent), pkt_module_(pkt_module),
work_queue_(TaskScheduler::GetInstance()->GetTaskId("Agent::PktHandler"), 0,
boost::bind(&PktHandler::ProcessPacket, this, _1)) {
work_queue_.set_name("Packet Handler Queue");
work_queue_.set_measure_busy_time(agent_->MeasureQueueDelay());
for (int i = 0; i < MAX_MODULES; ++i) {
if (i == PktHandler::DHCP || i == PktHandler::DHCPV6 ||
i == PktHandler::DNS)
pkt_trace_.at(i).set_pkt_trace_size(512);
else
pkt_trace_.at(i).set_pkt_trace_size(128);
}
}
PktHandler::~PktHandler() {
work_queue_.Shutdown();
}
void PktHandler::Register(PktModuleName type, Proto *proto) {
proto_list_.at(type) = proto;
}
uint32_t PktHandler::EncapHeaderLen() const {
return agent_->pkt()->control_interface()->EncapsulationLength();
}
// Send packet to tap interface
void PktHandler::Send(const AgentHdr &hdr, const PacketBufferPtr &buff) {
stats_.PktSent(PktHandler::PktModuleName(buff->module()));
pkt_trace_.at(buff->module()).AddPktTrace(PktTrace::Out, buff->data_len(),
buff->data(), &hdr);
if (agent_->pkt()->control_interface()->Send(hdr, buff) <= 0) {
PKT_TRACE(Err, "Error sending packet");
}
return;
}
void PktHandler::CalculatePort(PktInfo *pkt) {
const Interface *in = NULL;
const VmInterface *intf = NULL;
const NextHop *nh =
agent()->nexthop_table()->FindNextHop(pkt->agent_hdr.nh);
if (!nh) {
return;
}
if (nh->GetType() == NextHop::INTERFACE) {
const InterfaceNH *intf_nh = static_cast<const InterfaceNH *>(nh);
in = intf_nh->GetInterface();
} else if (nh->GetType() == NextHop::VLAN) {
const VlanNH *vlan_nh = static_cast<const VlanNH *>(nh);
in = vlan_nh->GetInterface();
}
if (in) {
intf = dynamic_cast<const VmInterface *>(in);
}
if (!intf) {
return;
}
if (intf->fat_flow_list().list_.size() == 0) {
return;
}
uint16_t sport = pkt->sport;
if (pkt->ip_proto == IPPROTO_ICMP) {
sport = 0;
}
if (pkt->sport < pkt->dport) {
if (intf->IsFatFlow(pkt->ip_proto, sport)) {
pkt->dport = 0;
return;
}
if (intf->IsFatFlow(pkt->ip_proto, pkt->dport)) {
pkt->sport = 0;
return;
}
return;
}
if (intf->IsFatFlow(pkt->ip_proto, pkt->dport)) {
pkt->sport = 0;
return;
}
if (intf->IsFatFlow(pkt->ip_proto, sport)) {
pkt->dport = 0;
return;
}
}
// Process the packet received from tap interface
PktHandler::PktModuleName PktHandler::ParsePacket(const AgentHdr &hdr,
PktInfo *pkt_info,
uint8_t *pkt) {
PktType::Type pkt_type = PktType::INVALID;
Interface *intf = NULL;
pkt_info->agent_hdr = hdr;
if (!IsValidInterface(hdr.ifindex, &intf)) {
return INVALID;
}
// Parse packet before computing forwarding mode. Packet is parsed
// indepndent of packet forwarding mode
if (ParseUserPkt(pkt_info, intf, pkt_type, pkt) < 0) {
return INVALID;
}
if (pkt_info->agent_hdr.cmd == AgentHdr::TRAP_TOR_CONTROL_PKT) {
// In case of a control packet from a TOR served by us, the ifindex
// is modified to index of the VM interface; validate this interface.
if (!IsValidInterface(pkt_info->agent_hdr.ifindex, &intf)) {
return INVALID;
}
}
// Compute L2/L3 forwarding mode for packet
pkt_info->l3_forwarding = ComputeForwardingMode(pkt_info);
pkt_info->vrf = pkt_info->agent_hdr.vrf;
bool is_flow_packet = IsFlowPacket(pkt_info);
// Look for DHCP packets if corresponding service is enabled
// Service processing over-rides ACL/Flow and forwarding configuration
if (!is_flow_packet && intf->dhcp_enabled() && (pkt_type == PktType::UDP)) {
if (pkt_info->ip && (pkt_info->dport == DHCP_SERVER_PORT ||
pkt_info->sport == DHCP_CLIENT_PORT)) {
return DHCP;
}
if (pkt_info->ip6 && (pkt_info->dport == DHCPV6_SERVER_PORT ||
pkt_info->sport == DHCPV6_CLIENT_PORT)) {
return DHCPV6;
}
}
if (intf->type() == Interface::VM_INTERFACE) {
VmInterface *vm_itf = static_cast<VmInterface *>(intf);
if (pkt_info->l3_forwarding && vm_itf->layer3_forwarding() == false) {
PKT_TRACE(Err, "layer3 not enabled for interface index <" <<
pkt_info->agent_hdr.ifindex << ">");
return INVALID;
}
if (pkt_info->l3_forwarding == false &&
vm_itf->bridging() == false) {
PKT_TRACE(Err, "bridging not enabled for interface "
"index <" << pkt_info->agent_hdr.ifindex << ">");
return INVALID;
}
}
// Handle ARP packet
if (pkt_type == PktType::ARP) {
return ARP;
}
// Packets needing flow
if (is_flow_packet) {
CalculatePort(pkt_info);
if ((pkt_info->ip && pkt_info->family == Address::INET) ||
(pkt_info->ip6 && pkt_info->family == Address::INET6)) {
return FLOW;
} else {
PKT_TRACE(Err, "Flow trap for non-IP packet for interface "
"index <" << hdr.ifindex << ">");
return INVALID;
}
}
// Look for DNS packets if corresponding service is enabled
// Service processing over-rides ACL/Flow
if (intf->dns_enabled() && (pkt_type == PktType::UDP)) {
if (pkt_info->dport == DNS_SERVER_PORT) {
return DNS;
}
}
// Look for IP packets that need ARP resolution
if (pkt_info->ip && hdr.cmd == AgentHdr::TRAP_RESOLVE) {
return ARP;
}
// send time exceeded ICMP messages to diag module
if (IsDiagPacket(pkt_info)) {
return DIAG;
}
if (pkt_type == PktType::ICMP && IsGwPacket(intf, pkt_info->ip_daddr)) {
return ICMP;
}
if (pkt_type == PktType::ICMPV6) {
if (hdr.cmd == AgentHdr::TRAP_HANDLE_DF) {
return ICMPV6_ERROR;
}
return ICMPV6;
}
if(pkt_info->ip6 && hdr.cmd == AgentHdr::TRAP_HANDLE_DF) {
return ICMPV6_ERROR;
}
if (pkt_info->ip && hdr.cmd == AgentHdr::TRAP_HANDLE_DF) {
return ICMP_ERROR;
}
if (hdr.cmd == AgentHdr::TRAP_DIAG && pkt_info->ip) {
return DIAG;
}
return INVALID;
}
void PktHandler::HandleRcvPkt(const AgentHdr &hdr, const PacketBufferPtr &buff){
// Enqueue packets to a workqueue to decouple from ASIO and run in
// exclusion with DB
boost::shared_ptr<PacketBufferEnqueueItem>
info(new PacketBufferEnqueueItem(hdr, buff));
work_queue_.Enqueue(info);
}
bool PktHandler::ProcessPacket(boost::shared_ptr<PacketBufferEnqueueItem> item) {
agent_->stats()->incr_pkt_exceptions();
const AgentHdr &hdr = item->hdr;
const PacketBufferPtr &buff = item->buff;
boost::shared_ptr<PktInfo> pkt_info (new PktInfo(buff));
uint8_t *pkt = buff->data();
PktModuleName mod = ParsePacket(hdr, pkt_info.get(), pkt);
PktModuleEnqueue(mod, hdr, pkt_info, pkt);
return true;
}
void PktHandler::PktModuleEnqueue(PktModuleName mod, const AgentHdr &hdr,
boost::shared_ptr<PktInfo> pkt_info,
uint8_t * pkt) {
pkt_info->packet_buffer()->set_module(mod);
stats_.PktRcvd(mod);
if (mod == INVALID) {
agent_->stats()->incr_pkt_dropped();
pkt_trace_.at(mod).AddPktTrace(PktTrace::In, pkt_info->len, pkt, &hdr);
return;
}
Enqueue(mod, pkt_info);
}
PktHandler::PktModuleName PktHandler::ParseFlowPacket(
boost::shared_ptr<PktInfo> pkt_info, uint8_t *pkt) {
PktModuleName mod = ParsePacket(pkt_info->agent_hdr, pkt_info.get(), pkt);
// In case it is not a flow packet, enqueue it back to the right module
if (mod != FLOW) {
PktModuleEnqueue(mod, pkt_info->agent_hdr, pkt_info, pkt);
}
return mod;
}
// Compute L2/L3 forwarding mode for pacekt.
// Forwarding mode is L3 if,
// - Packet uses L3 label
// - DMAC in packet is VRRP Mac or VHOST MAC
// Else forwarding mode is L2
bool PktHandler::ComputeForwardingMode(PktInfo *pkt_info) const {
if (pkt_info->tunnel.type.GetType() == TunnelType::MPLS_GRE ||
pkt_info->tunnel.type.GetType() == TunnelType::MPLS_UDP) {
return pkt_info->l3_label;
}
if (pkt_info->dmac == agent_->vrrp_mac()) {
return true;
}
if (pkt_info->dmac == agent_->vhost_interface()->mac()) {
return true;
}
return false;
}
void PktHandler::SetOuterIp(PktInfo *pkt_info, uint8_t *pkt) {
if (pkt_info->ether_type != ETHERTYPE_IP) {
return;
}
struct ip *ip_hdr = (struct ip *)pkt;
pkt_info->tunnel.ip = ip_hdr;
pkt_info->tunnel.ip_saddr = ntohl(ip_hdr->ip_src.s_addr);
pkt_info->tunnel.ip_daddr = ntohl(ip_hdr->ip_dst.s_addr);
}
void PktHandler::SetOuterMac(PktInfo *pkt_info) {
pkt_info->tunnel.eth = pkt_info->eth;
}
static bool InterestedIPv6Protocol(uint8_t proto) {
if (proto == IPPROTO_UDP || proto == IPPROTO_TCP ||
proto == IPPROTO_ICMPV6) {
return true;
}
return false;
}
int PktHandler::ParseEthernetHeader(PktInfo *pkt_info, uint8_t *pkt) {
int len = 0;
pkt_info->eth = (struct ether_header *) (pkt + len);
pkt_info->smac = MacAddress(pkt_info->eth->ether_shost);
pkt_info->dmac = MacAddress(pkt_info->eth->ether_dhost);
pkt_info->ether_type = ntohs(pkt_info->eth->ether_type);
len += sizeof(struct ether_header);
if (pkt_info->ether_type == ETHERTYPE_VLAN) {
pkt_info->ether_type = ntohs(*((uint16_t *)(pkt + len + 2)));
len += VLAN_HDR_LEN;
}
return len;
}
int PktHandler::ParseIpPacket(PktInfo *pkt_info, PktType::Type &pkt_type,
uint8_t *pkt) {
int len = 0;
if (pkt_info->ether_type == ETHERTYPE_IP) {
struct ip *ip = (struct ip *)(pkt + len);
pkt_info->ip = ip;
pkt_info->family = Address::INET;
pkt_info->ip_saddr = IpAddress(Ip4Address(ntohl(ip->ip_src.s_addr)));
pkt_info->ip_daddr = IpAddress(Ip4Address(ntohl(ip->ip_dst.s_addr)));
pkt_info->ip_proto = ip->ip_p;
pkt_info->ttl = ip->ip_ttl;
len += (ip->ip_hl << 2);
} else if (pkt_info->ether_type == ETHERTYPE_IPV6) {
pkt_info->family = Address::INET6;
ip6_hdr *ip = (ip6_hdr *)(pkt + len);
pkt_info->ip6 = ip;
pkt_info->ip = NULL;
Ip6Address::bytes_type addr;
for (int i = 0; i < 16; i++) {
addr[i] = ip->ip6_src.s6_addr[i];
}
pkt_info->ip_saddr = IpAddress(Ip6Address(addr));
for (int i = 0; i < 16; i++) {
addr[i] = ip->ip6_dst.s6_addr[i];
}
pkt_info->ip_daddr = IpAddress(Ip6Address(addr));
pkt_info->ttl = ip->ip6_hlim;
// Look for known transport headers. Fallback to the last header if
// no known header is found
uint8_t proto = ip->ip6_ctlun.ip6_un1.ip6_un1_nxt;
len += sizeof(ip6_hdr);
while (InterestedIPv6Protocol(proto) == false) {
struct ip6_ext *ext = (ip6_ext *)(pkt + len);
proto = ext->ip6e_nxt;
len += (ext->ip6e_len * 8);
if (ext->ip6e_len == 0) {
proto = 0;
break;
}
if (len >= pkt_info->len) {
proto = 0;
break;
}
}
pkt_info->ip_proto = proto;
} else {
assert(0);
}
switch (pkt_info->ip_proto) {
case IPPROTO_UDP : {
pkt_info->transp.udp = (udphdr *) (pkt + len);
len += sizeof(udphdr);
pkt_info->data = (pkt + len);
pkt_info->dport = ntohs(pkt_info->transp.udp->uh_dport);
pkt_info->sport = ntohs(pkt_info->transp.udp->uh_sport);
pkt_type = PktType::UDP;
break;
}
case IPPROTO_TCP : {
pkt_info->transp.tcp = (tcphdr *) (pkt + len);
len += sizeof(tcphdr);
pkt_info->data = (pkt + len);
pkt_info->dport = ntohs(pkt_info->transp.tcp->th_dport);
pkt_info->sport = ntohs(pkt_info->transp.tcp->th_sport);
pkt_info->tcp_ack = pkt_info->transp.tcp->th_flags & TH_ACK;
pkt_type = PktType::TCP;
break;
}
case IPPROTO_SCTP : {
pkt_info->transp.sctp = (sctphdr *) (pkt + len);
len += sizeof(sctphdr);
pkt_info->data = (pkt + len);
pkt_info->dport = ntohs(pkt_info->transp.sctp->th_dport);
pkt_info->sport = ntohs(pkt_info->transp.sctp->th_sport);
pkt_type = PktType::SCTP;
break;
}
case IPPROTO_ICMP: {
pkt_info->transp.icmp = (struct icmp *) (pkt + len);
pkt_type = PktType::ICMP;
struct icmp *icmp = (struct icmp *)(pkt + len);
pkt_info->dport = htons(icmp->icmp_type);
if (icmp->icmp_type == ICMP_ECHO || icmp->icmp_type == ICMP_ECHOREPLY) {
pkt_info->dport = ICMP_ECHOREPLY;
pkt_info->sport = htons(icmp->icmp_id);
} else if (IsFlowPacket(pkt_info) &&
((icmp->icmp_type == ICMP_DEST_UNREACH) ||
(icmp->icmp_type == ICMP_TIME_EXCEEDED))) {
//Agent has to look at inner payload
//and recalculate the parameter
//Handle this only for packets requiring flow miss
ParseIpPacket(pkt_info, pkt_type, pkt + len + sizeof(icmp));
//Swap the key parameter, which would be used as key
IpAddress src_ip = pkt_info->ip_saddr;
pkt_info->ip_saddr = pkt_info->ip_daddr;
pkt_info->ip_daddr = src_ip;
if (pkt_info->ip_proto != IPPROTO_ICMP) {
uint16_t port = pkt_info->sport;
pkt_info->sport = pkt_info->dport;
pkt_info->dport = port;
}
} else {
pkt_info->sport = 0;
}
break;
}
case IPPROTO_ICMPV6: {
pkt_type = PktType::ICMPV6;
icmp6_hdr *icmp = (icmp6_hdr *)(pkt + len);
pkt_info->transp.icmp6 = icmp;
pkt_info->dport = htons(icmp->icmp6_type);
if (icmp->icmp6_type == ICMP6_ECHO_REQUEST ||
icmp->icmp6_type == ICMP6_ECHO_REPLY) {
pkt_info->dport = ICMP6_ECHO_REPLY;
pkt_info->sport = htons(icmp->icmp6_id);
} else if (IsFlowPacket(pkt_info) &&
icmp->icmp6_type < ICMP6_ECHO_REQUEST) {
//Agent has to look at inner payload
//and recalculate the parameter
//Handle this only for packets requiring flow miss
ParseIpPacket(pkt_info, pkt_type, pkt + len + sizeof(icmp));
//Swap the key parameter, which would be used as key
IpAddress src_ip = pkt_info->ip_saddr;
pkt_info->ip_saddr = pkt_info->ip_daddr;
pkt_info->ip_daddr = src_ip;
if (pkt_info->ip_proto != IPPROTO_ICMPV6) {
uint16_t port = pkt_info->sport;
pkt_info->sport = pkt_info->dport;
pkt_info->dport = port;
}
} else {
pkt_info->sport = 0;
}
break;
}
default: {
pkt_type = PktType::IP;
pkt_info->dport = 0;
pkt_info->sport = 0;
break;
}
}
return len;
}
int PktHandler::ParseMplsHdr(PktInfo *pkt_info, uint8_t *pkt) {
MplsHdr *hdr = (MplsHdr *)(pkt);
// MPLS Header validation. Check for,
// - There is single label
uint32_t mpls_host = ntohl(hdr->hdr);
pkt_info->tunnel.label = (mpls_host & 0xFFFFF000) >> 12;
if ((mpls_host & 0x100) == 0) {
pkt_info->tunnel.label = MplsTable::kInvalidLabel;
PKT_TRACE(Err, "Unexpected MPLS Label Stack. Ignoring");
return -1;
}
uint32_t label = pkt_info->tunnel.label;
const MplsLabel *mpls = agent_->mpls_table()->FindMplsLabel(label);
if (mpls == NULL) {
PKT_TRACE(Err, "Invalid MPLS Label <" << label << ">. Ignoring");
pkt_info->tunnel.label = MplsTable::kInvalidLabel;
return -1;
}
pkt_info->l3_label = true;
const InterfaceNH *nh = dynamic_cast<const InterfaceNH *>(mpls->nexthop());
if (nh && nh->IsBridge()) {
pkt_info->l3_label = false;
}
return sizeof(MplsHdr);
}
// Parse MPLSoGRE header
int PktHandler::ParseMPLSoGRE(PktInfo *pkt_info, uint8_t *pkt) {
GreHdr *gre = (GreHdr *)(pkt);
if (gre->protocol != ntohs(VR_GRE_PROTO_MPLS)) {
PKT_TRACE(Err, "Non-MPLS protocol <" << ntohs(gre->protocol) <<
"> in GRE header");
return -1;
}
int len = sizeof(GreHdr);
int tmp;
tmp = ParseMplsHdr(pkt_info, (pkt + len));
if (tmp < 0) {
return tmp;
}
len += tmp;
if (pkt_info->l3_label == false) {
tmp = ParseEthernetHeader(pkt_info, (pkt + len));
if (tmp < 0)
return tmp;
len += tmp;
}
pkt_info->tunnel.type.SetType(TunnelType::MPLS_GRE);
return (len);
}
int PktHandler::ParseMPLSoUDP(PktInfo *pkt_info, uint8_t *pkt) {
int len = ParseMplsHdr(pkt_info, pkt);
if (len < 0) {
return len;
}
if (pkt_info->l3_label == false) {
len += ParseEthernetHeader(pkt_info, (pkt + len));
}
pkt_info->tunnel.type.SetType(TunnelType::MPLS_UDP);
return len;
}
int PktHandler::ParseVxlan(PktInfo *pkt_info, uint8_t *pkt) {
VxlanHdr *vxlan = (VxlanHdr *)(pkt);
pkt_info->tunnel.vxlan_id = htonl(vxlan->vxlan_id) >> 8;
int len = sizeof(vxlan);
len += ParseEthernetHeader(pkt_info, (pkt + len));
pkt_info->tunnel.type.SetType(TunnelType::VXLAN);
pkt_info->l3_label = false;
return len;
}
int PktHandler::ParseUDPTunnels(PktInfo *pkt_info, uint8_t *pkt) {
int len = 0;
if (pkt_info->dport == VXLAN_UDP_DEST_PORT)
len = ParseVxlan(pkt_info, (pkt + len));
else if (pkt_info->dport == MPLS_OVER_UDP_DEST_PORT ||
pkt_info->dport == IANA_MPLS_OVER_UDP_DEST_PORT)
len = ParseMPLSoUDP(pkt_info, (pkt + len));
return len;
}
int PktHandler::ParseUserPkt(PktInfo *pkt_info, Interface *intf,
PktType::Type &pkt_type, uint8_t *pkt) {
int len = 0;
// get to the actual packet header
len += ParseEthernetHeader(pkt_info, (pkt + len));
// Parse payload
if (pkt_info->ether_type == ETHERTYPE_ARP) {
pkt_info->arp = (ether_arp *) (pkt + len);
pkt_type = PktType::ARP;
return len;
}
// Identify NON-IP Packets
if (pkt_info->ether_type != ETHERTYPE_IP &&
pkt_info->ether_type != ETHERTYPE_IPV6) {
pkt_info->data = (pkt + len);
pkt_type = PktType::NON_IP;
return len;
}
// Copy IP fields from outer header assuming tunnel is present. If tunnel
// is not present, the values here will be ignored
SetOuterMac(pkt_info);
SetOuterIp(pkt_info, (pkt + len));
// IP Packets
len += ParseIpPacket(pkt_info, pkt_type, (pkt + len));
// If packet is an IP fragment and not flow trap, ignore it
if (IgnoreFragmentedPacket(pkt_info)) {
agent_->stats()->incr_pkt_fragments_dropped();
return -1;
}
// If it is a packet from TOR that we serve, dont parse any further
if (IsManagedTORPacket(intf, pkt_info, pkt_type, (pkt + len))) {
return len;
}
// If tunneling is not enabled on interface or if it is a DHCP packet,
// dont parse any further
if (intf->IsTunnelEnabled() == false || IsDHCPPacket(pkt_info) ||
(IsDiagPacket(pkt_info) &&
(pkt_info->agent_hdr.cmd != AgentHdr::TRAP_ROUTER_ALERT))) {
return len;
}
// Tunneling is enabled on interface. Reset pkt_type and decode payload
pkt_type = PktType::INVALID;
// Decap only IP-DA is ours
if (pkt_info->family != Address::INET ||
pkt_info->ip_daddr.to_v4() != agent_->router_id()) {
PKT_TRACE(Err, "Tunnel packet not destined to me. Ignoring");
return -1;
}
int tunnel_len = 0;
// Look for supported headers
switch (pkt_info->ip_proto) {
case IPPROTO_GRE :
// Parse MPLSoGRE tunnel
tunnel_len = ParseMPLSoGRE(pkt_info, (pkt + len));
break;
case IPPROTO_UDP:
// Parse MPLSoUDP tunnel
tunnel_len = ParseUDPTunnels(pkt_info, (pkt + len));
break;
default:
break;
}
if (tunnel_len < 0) {
pkt_type = PktType::INVALID;
return tunnel_len;
}
len += tunnel_len;
// Find IPv4/IPv6 Packet based on first nibble in payload
if (((pkt + len)[0] & 0x60) == 0x60) {
pkt_info->ether_type = ETHERTYPE_IPV6;
} else {
pkt_info->ether_type = ETHERTYPE_IP;
}
len += ParseIpPacket(pkt_info, pkt_type, (pkt + len));
return len;
}
// Enqueue an inter-task message to the specified module
void PktHandler::SendMessage(PktModuleName mod, InterTaskMsg *msg) {
if (mod < MAX_MODULES) {
boost::shared_ptr<PktInfo> pkt_info(new PktInfo(mod, msg));
if (!(proto_list_.at(mod)->Enqueue(pkt_info))) {
PKT_TRACE(Err, "Threshold exceeded while enqueuing IPC Message <" <<
mod << ">");
}
}
}
bool PktHandler::IgnoreFragmentedPacket(PktInfo *pkt_info) {
if (!pkt_info->ip)
return false;
uint16_t offset = htons(pkt_info->ip->ip_off);
if (((offset & IP_MF) || (offset & IP_OFFMASK)) &&
!IsFlowPacket(pkt_info))
return true;
return false;
}
bool PktHandler::IsDHCPPacket(PktInfo *pkt_info) {
if (pkt_info->dport == DHCP_SERVER_PORT ||
pkt_info->sport == DHCP_CLIENT_PORT) {
// we dont handle DHCPv6 coming from fabric
return true;
}
return false;
}
bool PktHandler::IsToRDevice(uint32_t vrf_id, const IpAddress &ip) {
if (agent()->tsn_enabled() == false)
return false;
if (ip.is_v4() == false)
return false;
Ip4Address ip4 = ip.to_v4();
VrfEntry *vrf = agent()->vrf_table()->FindVrfFromId(vrf_id);
if (vrf == NULL)
return false;
BridgeAgentRouteTable *table = static_cast<BridgeAgentRouteTable *>
(vrf->GetBridgeRouteTable());
if (table == NULL)
return false;
BridgeRouteEntry *rt = table->FindRoute(MacAddress::BroadcastMac());
if (rt == NULL)
return false;
const CompositeNH *nh = dynamic_cast<const CompositeNH *>
(rt->GetActiveNextHop());
if (nh == NULL)
return false;
ComponentNHList::const_iterator it = nh->begin();
while (it != nh->end()) {
const CompositeNH *tor_nh = dynamic_cast<const CompositeNH *>
((*it)->nh());
if (tor_nh == NULL) {
it++;
continue;
}
if (tor_nh->composite_nh_type() != Composite::TOR) {
it++;
continue;
}
ComponentNHList::const_iterator tor_it = tor_nh->begin();
while (tor_it != tor_nh->end()) {
const TunnelNH *tun_nh = dynamic_cast<const TunnelNH *>
((*tor_it)->nh());
if (tun_nh == NULL) {
tor_it++;
continue;
}
if (*tun_nh->GetDip() == ip4) {
return true;
}
tor_it++;
}
it++;
}
return false;
}
// We can receive DHCP / DNS packets on physical port from TOR ports managed
// by a TOR services node. Check if the source mac is the mac address of a
// VM interface available in the node.
bool PktHandler::IsManagedTORPacket(Interface *intf, PktInfo *pkt_info,
PktType::Type &pkt_type, uint8_t *pkt) {
if (intf->type() != Interface::PHYSICAL) {
return false;
}
if (pkt_type != PktType::UDP || pkt_info->dport != VXLAN_UDP_DEST_PORT)
return false;
// Get VXLAN id and point to original L2 frame after the VXLAN header
pkt += 8;
// get to the actual packet header
pkt += ParseEthernetHeader(pkt_info, pkt);
ether_addr addr;
memcpy(addr.ether_addr_octet, pkt_info->eth->ether_shost, ETH_ALEN);
MacAddress address(addr);
const VrfEntry *vrf = agent_->vrf_table()->
FindVrfFromId(pkt_info->agent_hdr.vrf);
if (vrf == NULL)
return false;
BridgeAgentRouteTable *bridge_table =
dynamic_cast<BridgeAgentRouteTable *>(vrf->GetBridgeRouteTable());
assert(bridge_table != NULL);
const VmInterface *vm_intf = bridge_table->FindVmFromDhcpBinding(address);
if (vm_intf == NULL) {
return false;
}
if (IsToRDevice(vm_intf->vrf_id(), pkt_info->ip_saddr) == false) {
return false;
}
// update agent_hdr to reflect the VM interface data
// cmd_param is set to physical interface id
pkt_info->agent_hdr.cmd = AgentHdr::TRAP_TOR_CONTROL_PKT;
pkt_info->agent_hdr.cmd_param = pkt_info->agent_hdr.ifindex;
pkt_info->agent_hdr.ifindex = vm_intf->id();
// Parse payload
if (pkt_info->ether_type == ETHERTYPE_ARP) {
pkt_info->arp = (ether_arp *) pkt;
pkt_type = PktType::ARP;
return true;
}
// Identify NON-IP Packets
if (pkt_info->ether_type != ETHERTYPE_IP &&
pkt_info->ether_type != ETHERTYPE_IPV6) {
pkt_info->data = pkt;
pkt_type = PktType::NON_IP;
return true;
}
// IP Packets
ParseIpPacket(pkt_info, pkt_type, pkt);
return true;
}
bool PktHandler::IsFlowPacket(PktInfo *pkt_info) {
if (pkt_info->agent_hdr.cmd == AgentHdr::TRAP_FLOW_MISS ||
pkt_info->agent_hdr.cmd == AgentHdr::TRAP_ECMP_RESOLVE ||
pkt_info->agent_hdr.cmd == AgentHdr::TRAP_HOLD_ACTION) {
return true;
}
return false;
}
bool PktHandler::IsFlowPacket(const AgentHdr &agent_hdr) {
if (agent_hdr.cmd == AgentHdr::TRAP_FLOW_MISS ||
agent_hdr.cmd == AgentHdr::TRAP_ECMP_RESOLVE ||
agent_hdr.cmd == AgentHdr::TRAP_FLOW_ACTION_HOLD) {
return true;
}
return false;
}
bool PktHandler::IsDiagPacket(PktInfo *pkt_info) {
if (pkt_info->agent_hdr.cmd == AgentHdr::TRAP_ZERO_TTL ||
pkt_info->agent_hdr.cmd == AgentHdr::TRAP_ICMP_ERROR
|| pkt_info->agent_hdr.cmd == AgentHdr::TRAP_ROUTER_ALERT)
return true;
return false;
}
// Check if the packet is destined to the VM's default GW
bool PktHandler::IsGwPacket(const Interface *intf, const IpAddress &dst_ip) {
if (!intf || intf->type() != Interface::VM_INTERFACE)
return false;
const VmInterface *vm_intf = static_cast<const VmInterface *>(intf);
if (vm_intf->vmi_type() != VmInterface::GATEWAY) {
//Gateway interface doesnt have IP address
if (dst_ip.is_v6() && vm_intf->primary_ip6_addr().is_unspecified())
return false;
else if (dst_ip.is_v4() && vm_intf->primary_ip_addr().is_unspecified())
return false;
}
const VnEntry *vn = vm_intf->vn();
if (vn) {
const std::vector<VnIpam> &ipam = vn->GetVnIpam();
for (unsigned int i = 0; i < ipam.size(); ++i) {
if (dst_ip.is_v4()) {
if (!ipam[i].IsV4()) {
continue;
}
if (ipam[i].default_gw == dst_ip ||
ipam[i].dns_server == dst_ip) {
return true;
}
} else {
if (!ipam[i].IsV6()) {
continue;
}
if (ipam[i].default_gw == dst_ip ||
ipam[i].dns_server == dst_ip) {
return true;
}
}
}
}
return false;
}
bool PktHandler::IsValidInterface(uint32_t ifindex, Interface **interface) {
Interface *intf = agent_->interface_table()->FindInterface(ifindex);
if (intf == NULL) {
PKT_TRACE(Err, "Invalid interface index <" << ifindex << ">");
agent_->stats()->incr_pkt_invalid_interface();
return false;
}
*interface = intf;
return true;
}
void PktHandler::PktTraceIterate(PktModuleName mod, PktTraceCallback cb) {
if (!cb.empty()) {
PktTrace &pkt(pkt_trace_.at(mod));
pkt.Iterate(cb);
}
}
void PktHandler::PktStats::PktRcvd(PktModuleName mod) {
if (mod < MAX_MODULES)
received[mod]++;
}
void PktHandler::PktStats::PktSent(PktModuleName mod) {
if (mod < MAX_MODULES)
sent[mod]++;
}
void PktHandler::PktStats::PktQThresholdExceeded(PktModuleName mod) {
if (mod < MAX_MODULES)
q_threshold_exceeded[mod]++;
}
///////////////////////////////////////////////////////////////////////////////
PktInfo::PktInfo(const PacketBufferPtr &buff) :
module(PktHandler::INVALID),
pkt(buff->data()), len(buff->data_len()), max_pkt_len(buff->buffer_len()),
data(), ipc(), family(Address::UNSPEC), type(PktType::INVALID), agent_hdr(),
ether_type(-1), ip_saddr(), ip_daddr(), ip_proto(), sport(), dport(),
ttl(0), tcp_ack(false), tunnel(), l3_forwarding(false),
l3_label(false), eth(), arp(), ip(), ip6(), packet_buffer_(buff) {
transp.tcp = 0;
}
PktInfo::PktInfo(const PacketBufferPtr &buff, const AgentHdr &hdr) :
pkt(buff->data()), len(buff->data_len()), max_pkt_len(buff->buffer_len()),
data(), ipc(), family(Address::UNSPEC), type(PktType::INVALID),
agent_hdr(hdr), ether_type(-1), ip_saddr(), ip_daddr(), ip_proto(), sport(),
dport(), ttl(0), tcp_ack(false), tunnel(), l3_forwarding(false),
l3_label(false), eth(), arp(), ip(), ip6(), packet_buffer_(buff) {
transp.tcp = 0;
}
PktInfo::PktInfo(Agent *agent, uint32_t buff_len, PktHandler::PktModuleName mod,
uint32_t mdata) :
module(mod),
len(), max_pkt_len(), data(), ipc(), family(Address::UNSPEC),
type(PktType::INVALID), agent_hdr(), ether_type(-1), ip_saddr(), ip_daddr(),
ip_proto(), sport(), dport(), ttl(0), tcp_ack(false), tunnel(),
l3_forwarding(false), l3_label(false), eth(), arp(), ip(), ip6() {