/* static */ void IPv6RouteAdvertiser::createAdvertisementPacket(
const Interface* intf,
folly::io::RWPrivateCursor* cursor,
folly::MacAddress dstMac,
const folly::IPAddressV6& dstIP) {
const auto* ndpConfig = &intf->getNdpConfig();
// Settings
uint8_t hopLimit = ndpConfig->curHopLimit;
// Set managed and other bits in router advertisements.
// These bits control whether address and other information
// (e.g. where to grab the image) is available via DHCP.
uint8_t flags = 0;
if (ndpConfig->routerAdvertisementManagedBit) {
flags |= ND_RA_FLAG_MANAGED;
}
if (ndpConfig->routerAdvertisementOtherBit) {
flags |= ND_RA_FLAG_OTHER;
}
std::chrono::seconds lifetime(ndpConfig->routerLifetime);
std::chrono::seconds reachableTimer(0);
std::chrono::seconds retransTimer(0);
uint32_t prefixValidLifetime = ndpConfig->prefixValidLifetimeSeconds;
uint32_t prefixPreferredLifetime = ndpConfig->prefixPreferredLifetimeSeconds;
// Build the list of prefixes to advertise
typedef std::pair<IPAddressV6, uint8_t> Prefix;
uint32_t mtu = intf->getMtu();
std::set<Prefix> prefixes;
foreachAddrToAdvertise(intf, [&](
const std::pair<folly::IPAddress, uint8_t> & addr) {
uint8_t mask = addr.second;
prefixes.emplace(addr.first.asV6().mask(mask), mask);
});
auto serializeBody = [&](RWPrivateCursor* cursor) {
cursor->writeBE<uint8_t>(hopLimit);
cursor->writeBE<uint8_t>(flags);
cursor->writeBE<uint16_t>(lifetime.count());
cursor->writeBE<uint32_t>(reachableTimer.count());
cursor->writeBE<uint32_t>(retransTimer.count());
// Source MAC option
cursor->writeBE<uint8_t>(1); // Option type (src link-layer address)
cursor->writeBE<uint8_t>(1); // Option length = 1 (x8)
cursor->push(intf->getMac().bytes(), MacAddress::SIZE);
// Prefix options
for (const auto& prefix : prefixes) {
cursor->writeBE<uint8_t>(3); // Option type (prefix information)
cursor->writeBE<uint8_t>(4); // Option length = 4 (x8)
cursor->writeBE<uint8_t>(prefix.second);
uint8_t prefixFlags = 0xc0; // on link, autonomous address configuration
cursor->writeBE<uint8_t>(prefixFlags);
cursor->writeBE<uint32_t>(prefixValidLifetime);
cursor->writeBE<uint32_t>(prefixPreferredLifetime);
cursor->writeBE<uint32_t>(0); // reserved
cursor->push(prefix.first.bytes(), IPAddressV6::byteCount());
}
// MTU option
cursor->writeBE<uint8_t>(5); // Option type (MTU)
cursor->writeBE<uint8_t>(1); // Option length = 1 (x8)
cursor->writeBE<uint16_t>(0); // Reserved
cursor->writeBE<uint32_t>(mtu);
};
auto bodyLength = getAdvertisementPacketBodySize(prefixes.size());
IPAddressV6 srcIP(IPAddressV6::LINK_LOCAL, intf->getMac());
IPv6Hdr ipv6(srcIP, dstIP);
ipv6.trafficClass = 0xe0; // CS7 precedence (network control)
ipv6.payloadLength = ICMPHdr::SIZE + bodyLength;
ipv6.nextHeader = IP_PROTO_IPV6_ICMP;
ipv6.hopLimit = 255;
ICMPHdr icmp6(ICMPV6_TYPE_NDP_ROUTER_ADVERTISEMENT, 0, 0);
icmp6.serializeFullPacket(cursor, dstMac, intf->getMac(), intf->getVlanID(),
ipv6, bodyLength, serializeBody);
}
Packet Entry::getSample(void){
IP srcIP(srcMask[0], srcMask[1], srcMask[2], srcMask[3]);
IP dstIP(dstMask[0], dstMask[1], dstMask[2], dstMask[3]);
Packet pkt(srcIP, dstIP, srcPort, dstPort, protocol);
return pkt;
}
