/
pkt_handler.cc
1071 lines (907 loc) · 32.6 KB
/
pkt_handler.cc
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/*
* 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/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) {
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() {
}
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;
agent_->stats()->incr_pkt_exceptions();
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);
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;
}
}
pkt_info->vrf = pkt_info->agent_hdr.vrf;
// Handle ARP packet
if (pkt_type == PktType::ARP) {
return ARP;
}
if (IsFlowPacket(pkt_info)) {
CalculatePort(pkt_info);
}
// Packets needing flow
if (IsFlowPacket(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;
}
}
// Handle ARP packet
if (pkt_type == PktType::ARP) {
return ARP;
}
// Look for DHCP and DNS packets if corresponding service is enabled
// Service processing over-rides ACL/Flow
if (intf->dhcp_enabled() && (pkt_type == PktType::UDP)) {
if (pkt_info->dport == DHCP_SERVER_PORT ||
pkt_info->sport == DHCP_CLIENT_PORT) {
return DHCP;
}
if (pkt_info->dport == DHCPV6_SERVER_PORT ||
pkt_info->sport == DHCPV6_CLIENT_PORT) {
return DHCPV6;
}
}
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->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){
boost::shared_ptr<PktInfo> pkt_info(new PktInfo(buff));
PktModuleName mod = INVALID;
mod = ParsePacket(hdr, pkt_info.get(), pkt_info->packet_buffer()->data());
pkt_info->packet_buffer()->set_module(mod);
pkt_info->module = mod;
stats_.PktRcvd(mod);
if (mod == INVALID) {
AddPktTrace(mod, PktTrace::In, pkt_info.get());
agent_->stats()->incr_pkt_dropped();
return;
}
Enqueue(mod, pkt_info);
return;
}
// 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_saddr = ntohl(ip_hdr->ip_src.s_addr);
pkt_info->tunnel.ip_daddr = ntohl(ip_hdr->ip_dst.s_addr);
}
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;
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));
// 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) {
//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
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)) {
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::IsDiagPacket(PktInfo *pkt_info) {
if (pkt_info->agent_hdr.cmd == AgentHdr::TRAP_ZERO_TTL ||
pkt_info->agent_hdr.cmd == AgentHdr::TRAP_ICMP_ERROR)
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;
}
IpAddress src_ip = vm_intf->primary_ip_addr();
if (vm_intf->vmi_type() == VmInterface::GATEWAY) {
src_ip = vm_intf->subnet();
}
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) {
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(),
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(), tcp_ack(false), tunnel(),
l3_forwarding(false), l3_label(false), eth(), arp(), ip(), ip6() {
packet_buffer_ = agent->pkt()->packet_buffer_manager()->Allocate
(module, buff_len, mdata);
pkt = packet_buffer_->data();
len = packet_buffer_->data_len();
max_pkt_len = packet_buffer_->buffer_len();
transp.tcp = 0;
}
PktInfo::PktInfo(PktHandler::PktModuleName mod, InterTaskMsg *msg) :
module(mod),
pkt(), len(), max_pkt_len(0), data(), ipc(msg), family(Address::UNSPEC),
type(PktType::MESSAGE), agent_hdr(), ether_type(-1), ip_saddr(), ip_daddr(),
ip_proto(), sport(), dport(), tcp_ack(false), tunnel(),
l3_forwarding(false), l3_label(false), eth(), arp(), ip(), ip6(),
packet_buffer_() {
transp.tcp = 0;
}
PktInfo::~PktInfo() {
}
const AgentHdr &PktInfo::GetAgentHdr() const {
return agent_hdr;
}
void PktInfo::reset_packet_buffer() {
packet_buffer_.reset();
}
void PktInfo::AllocPacketBuffer(Agent *agent, uint32_t module, uint16_t len,
uint32_t mdata) {
packet_buffer_ = agent->pkt()->packet_buffer_manager()->Allocate
(module, len, mdata);
pkt = packet_buffer_->data();
len = packet_buffer_->data_len();
max_pkt_len = packet_buffer_->buffer_len();
}
void PktInfo::set_len(uint32_t x) {
packet_buffer_->set_len(x);
len = x;
}
void PktInfo::UpdateHeaderPtr() {
eth = (struct ether_header *)(pkt);
ip = (struct ip *)(eth + 1);
transp.tcp = (struct tcphdr *)(ip + 1);
}
std::size_t PktInfo::hash(const EcmpLoadBalance &ecmp_load_balance) const {
std::size_t seed = 0;
if (family == Address::INET) {