mirror of
https://github.com/zerotier/ZeroTierOne.git
synced 2025-01-29 15:43:52 +00:00
Add IPv6 Neighbor Discovery code. Not yet tested.
This commit is contained in:
Grant Limberg
parent
f0794e09b7
commit
d817039f79
262
osdep/NeighborDiscovery.cpp
Normal file
262
osdep/NeighborDiscovery.cpp
Normal file
@ -0,0 +1,262 @@
|
||||
/*
|
||||
* ZeroTier One - Network Virtualization Everywhere
|
||||
* Copyright (C) 2011-2016 ZeroTier, Inc. https://www.zerotier.com/
|
||||
*
|
||||
* This program is free software: you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License as published by
|
||||
* the Free Software Foundation, either version 3 of the License, or
|
||||
* (at your option) any later version.
|
||||
*
|
||||
* This program is distributed in the hope that it will be useful,
|
||||
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
* GNU General Public License for more details.
|
||||
*
|
||||
* You should have received a copy of the GNU General Public License
|
||||
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||
*/
|
||||
|
||||
#include "NeighborDiscovery.hpp"
|
||||
#include "OSUtils.hpp"
|
||||
|
||||
#include "../include/ZeroTierOne.h"
|
||||
|
||||
#include <assert.h>
|
||||
|
||||
namespace ZeroTier {
|
||||
|
||||
uint16_t calc_checksum (uint16_t *addr, int len)
|
||||
{
|
||||
int count = len;
|
||||
register uint32_t sum = 0;
|
||||
uint16_t answer = 0;
|
||||
|
||||
// Sum up 2-byte values until none or only one byte left.
|
||||
while (count > 1) {
|
||||
sum += *(addr++);
|
||||
count -= 2;
|
||||
}
|
||||
|
||||
// Add left-over byte, if any.
|
||||
if (count > 0) {
|
||||
sum += *(uint8_t *) addr;
|
||||
}
|
||||
|
||||
// Fold 32-bit sum into 16 bits; we lose information by doing this,
|
||||
// increasing the chances of a collision.
|
||||
// sum = (lower 16 bits) + (upper 16 bits shifted right 16 bits)
|
||||
while (sum >> 16) {
|
||||
sum = (sum & 0xffff) + (sum >> 16);
|
||||
}
|
||||
|
||||
// Checksum is one's compliment of sum.
|
||||
answer = ~sum;
|
||||
|
||||
return (answer);
|
||||
}
|
||||
|
||||
struct _pseudo_header {
|
||||
uint8_t sourceAddr[16];
|
||||
uint8_t targetAddr[16];
|
||||
uint32_t length;
|
||||
uint8_t zeros[3];
|
||||
uint8_t next; // 58
|
||||
};
|
||||
|
||||
struct _option {
|
||||
_option(int optionType)
|
||||
: type(optionType)
|
||||
, length(8)
|
||||
{
|
||||
memset(mac, 0, sizeof(mac));
|
||||
}
|
||||
|
||||
uint8_t type;
|
||||
uint8_t length;
|
||||
uint8_t mac[6];
|
||||
};
|
||||
|
||||
struct _neighbor_solicitation {
|
||||
_neighbor_solicitation()
|
||||
: type(135)
|
||||
, code(0)
|
||||
, checksum(0)
|
||||
, option(1)
|
||||
{
|
||||
memset(target, 0, sizeof(target));
|
||||
}
|
||||
|
||||
void calculateChecksum(const sockaddr_storage &sourceIp, const sockaddr_storage &destIp) {
|
||||
_pseudo_header ph;
|
||||
memset(&ph, 0, sizeof(_pseudo_header));
|
||||
const sockaddr_in6 *src = (const sockaddr_in6*)&sourceIp;
|
||||
const sockaddr_in6 *dest = (const sockaddr_in6*)&destIp;
|
||||
|
||||
memcpy(ph.sourceAddr, &src->sin6_addr, sizeof(struct in6_addr));
|
||||
memcpy(ph.targetAddr, &dest->sin6_addr, sizeof(struct in6_addr));
|
||||
ph.next = 58;
|
||||
ph.length = htonl(sizeof(_neighbor_solicitation));
|
||||
|
||||
size_t len = sizeof(_pseudo_header) + sizeof(_neighbor_solicitation);
|
||||
uint8_t *tmp = (uint8_t*)malloc(len);
|
||||
memcpy(tmp, &ph, sizeof(_pseudo_header));
|
||||
memcpy(tmp+sizeof(_pseudo_header), this, sizeof(_neighbor_solicitation));
|
||||
|
||||
checksum = calc_checksum((uint16_t*)tmp, len);
|
||||
|
||||
free(tmp);
|
||||
tmp = NULL;
|
||||
}
|
||||
|
||||
uint8_t type; // 135
|
||||
uint8_t code; // 0
|
||||
uint16_t checksum;
|
||||
uint8_t target[16];
|
||||
_option option;
|
||||
};
|
||||
|
||||
struct _neighbor_advertisement {
|
||||
_neighbor_advertisement()
|
||||
: type(136)
|
||||
, code(0)
|
||||
, checksum(0)
|
||||
, rso(0x40)
|
||||
, option(2)
|
||||
{
|
||||
memset(padding, 0, sizeof(padding));
|
||||
memset(target, 0, sizeof(target));
|
||||
}
|
||||
|
||||
void calculateChecksum(const sockaddr_storage &sourceIp, const sockaddr_storage &destIp) {
|
||||
_pseudo_header ph;
|
||||
memset(&ph, 0, sizeof(_pseudo_header));
|
||||
const sockaddr_in6 *src = (const sockaddr_in6*)&sourceIp;
|
||||
const sockaddr_in6 *dest = (const sockaddr_in6*)&destIp;
|
||||
|
||||
memcpy(ph.sourceAddr, &src->sin6_addr, sizeof(struct in6_addr));
|
||||
memcpy(ph.targetAddr, &dest->sin6_addr, sizeof(struct in6_addr));
|
||||
ph.next = 58;
|
||||
ph.length = htonl(sizeof(_neighbor_advertisement));
|
||||
|
||||
size_t len = sizeof(_pseudo_header) + sizeof(_neighbor_advertisement);
|
||||
uint8_t *tmp = (uint8_t*)malloc(len);
|
||||
memcpy(tmp, &ph, sizeof(_pseudo_header));
|
||||
memcpy(tmp+sizeof(_pseudo_header), this, sizeof(_neighbor_advertisement));
|
||||
|
||||
checksum = calc_checksum((uint16_t*)tmp, len);
|
||||
|
||||
free(tmp);
|
||||
tmp = NULL;
|
||||
}
|
||||
|
||||
uint8_t type; // 136
|
||||
uint8_t code; // 0
|
||||
uint16_t checksum;
|
||||
uint8_t rso;
|
||||
uint8_t padding[3];
|
||||
uint8_t target[16];
|
||||
_option option;
|
||||
};
|
||||
|
||||
NeighborDiscovery::NeighborDiscovery()
|
||||
: _cache(256)
|
||||
, _lastCleaned(OSUtils::now())
|
||||
{}
|
||||
|
||||
void NeighborDiscovery::addLocal(const sockaddr_storage &address, const MAC &mac)
|
||||
{
|
||||
_NDEntry &e = _cache[InetAddress(address)];
|
||||
e.lastQuerySent = 0;
|
||||
e.lastResponseReceived = 0;
|
||||
e.mac = mac;
|
||||
e.local = true;
|
||||
}
|
||||
|
||||
void NeighborDiscovery::remove(const sockaddr_storage &address)
|
||||
{
|
||||
_cache.erase(InetAddress(address));
|
||||
}
|
||||
|
||||
sockaddr_storage NeighborDiscovery::processIncomingND(const uint8_t *nd, unsigned int len, const sockaddr_storage &localIp, uint8_t *response, unsigned int &responseLen, MAC &responseDest)
|
||||
{
|
||||
assert(sizeof(_neighbor_solicitation) == 28);
|
||||
assert(sizeof(_neighbor_advertisement) == 30);
|
||||
|
||||
const uint64_t now = OSUtils::now();
|
||||
sockaddr_storage ip = ZT_SOCKADDR_NULL;
|
||||
|
||||
if (len >= sizeof(_neighbor_solicitation) && nd[0] == 0x87) {
|
||||
// respond to Neighbor Solicitation request for local address
|
||||
_neighbor_solicitation solicitation;
|
||||
memcpy(&solicitation, nd, len);
|
||||
InetAddress targetAddress(solicitation.target, 16, 0);
|
||||
_NDEntry *targetEntry = _cache.get(targetAddress);
|
||||
if (targetEntry && targetEntry->local) {
|
||||
_neighbor_advertisement adv;
|
||||
targetEntry->mac.copyTo(adv.option.mac, 6);
|
||||
memcpy(adv.target, solicitation.target, 16);
|
||||
adv.calculateChecksum(localIp, targetAddress);
|
||||
memcpy(response, &adv, sizeof(_neighbor_advertisement));
|
||||
responseLen = sizeof(_neighbor_advertisement);
|
||||
responseDest.setTo(solicitation.option.mac, 6);
|
||||
}
|
||||
} else if (len >= sizeof(_neighbor_advertisement) && nd[0] == 0x88) {
|
||||
_neighbor_advertisement adv;
|
||||
memcpy(&adv, nd, len);
|
||||
InetAddress responseAddress(adv.target, 16, 0);
|
||||
_NDEntry *queryEntry = _cache.get(responseAddress);
|
||||
if(queryEntry && !queryEntry->local && (now - queryEntry->lastQuerySent <= ZT_ND_QUERY_MAX_TTL)) {
|
||||
queryEntry->lastResponseReceived = now;
|
||||
queryEntry->mac.setTo(adv.option.mac, 6);
|
||||
ip = responseAddress;
|
||||
}
|
||||
}
|
||||
|
||||
if ((now - _lastCleaned) >= ZT_ND_EXPIRE) {
|
||||
_lastCleaned = now;
|
||||
Hashtable<InetAddress, _NDEntry>::Iterator i(_cache);
|
||||
InetAddress *k = NULL;
|
||||
_NDEntry *v = NULL;
|
||||
while (i.next(k, v)) {
|
||||
if(!v->local && (now - v->lastResponseReceived) >= ZT_ND_EXPIRE) {
|
||||
_cache.erase(*k);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return ip;
|
||||
}
|
||||
|
||||
MAC NeighborDiscovery::query(const MAC &localMac, const sockaddr_storage &localIp, const sockaddr_storage &targetIp, uint8_t *query, unsigned int &queryLen, MAC &queryDest)
|
||||
{
|
||||
const uint64_t now = OSUtils::now();
|
||||
|
||||
InetAddress localAddress(localIp);
|
||||
localAddress.setPort(0);
|
||||
InetAddress targetAddress(targetIp);
|
||||
targetAddress.setPort(0);
|
||||
|
||||
_NDEntry &e = _cache[targetAddress];
|
||||
|
||||
if ( (e.mac && ((now - e.lastResponseReceived) >= (ZT_ND_EXPIRE / 3))) ||
|
||||
(!e.mac && ((now - e.lastQuerySent) >= ZT_ND_QUERY_INTERVAL))) {
|
||||
e.lastQuerySent = now;
|
||||
|
||||
_neighbor_solicitation ns;
|
||||
memcpy(ns.target, targetAddress.rawIpData(), 16);
|
||||
localMac.copyTo(ns.option.mac, 6);
|
||||
ns.calculateChecksum(localIp, targetIp);
|
||||
if (e.mac) {
|
||||
queryDest = e.mac;
|
||||
} else {
|
||||
queryDest = (uint64_t)0xffffffffffffULL;
|
||||
}
|
||||
} else {
|
||||
queryLen = 0;
|
||||
queryDest.zero();
|
||||
}
|
||||
|
||||
return e.mac;
|
||||
}
|
||||
|
||||
}
|
||||
76
osdep/NeighborDiscovery.hpp
Normal file
76
osdep/NeighborDiscovery.hpp
Normal file
@ -0,0 +1,76 @@
|
||||
/*
|
||||
* ZeroTier One - Network Virtualization Everywhere
|
||||
* Copyright (C) 2011-2016 ZeroTier, Inc. https://www.zerotier.com/
|
||||
*
|
||||
* This program is free software: you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License as published by
|
||||
* the Free Software Foundation, either version 3 of the License, or
|
||||
* (at your option) any later version.
|
||||
*
|
||||
* This program is distributed in the hope that it will be useful,
|
||||
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
* GNU General Public License for more details.
|
||||
*
|
||||
* You should have received a copy of the GNU General Public License
|
||||
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||
*/
|
||||
|
||||
#ifndef ZT_NEIGHBORDISCOVERY_HPP
|
||||
#define ZT_NEIGHBORDISCOVERY_HPP
|
||||
|
||||
#include "../node/Hashtable.hpp"
|
||||
#include "../node/MAC.hpp"
|
||||
#include "../node/InetAddress.hpp"
|
||||
|
||||
|
||||
#define ZT_ND_QUERY_INTERVAL 2000
|
||||
|
||||
#define ZT_ND_QUERY_MAX_TTL 5000
|
||||
|
||||
#define ZT_ND_EXPIRE 600000
|
||||
|
||||
|
||||
namespace ZeroTier {
|
||||
|
||||
class NeighborDiscovery
|
||||
{
|
||||
public:
|
||||
NeighborDiscovery();
|
||||
|
||||
/**
|
||||
* Set a local IP entry that we should respond to Neighbor Requests withPrefix64k
|
||||
*
|
||||
* @param mac Our local MAC address
|
||||
* @param ip Our IPv6 address
|
||||
*/
|
||||
void addLocal(const sockaddr_storage &address, const MAC &mac);
|
||||
|
||||
/**
|
||||
* Delete a local IP entry or cached Neighbor entry
|
||||
*
|
||||
* @param address IPv6 address to remove
|
||||
*/
|
||||
void remove(const sockaddr_storage &address);
|
||||
|
||||
sockaddr_storage processIncomingND(const uint8_t *nd, unsigned int len, const sockaddr_storage &localIp, uint8_t *response, unsigned int &responseLen, MAC &responseDest);
|
||||
|
||||
MAC query(const MAC &localMac, const sockaddr_storage &localIp, const sockaddr_storage &targetIp, uint8_t *query, unsigned int &queryLen, MAC &queryDest);
|
||||
|
||||
private:
|
||||
struct _NDEntry
|
||||
{
|
||||
_NDEntry() : lastQuerySent(0), lastResponseReceived(0), mac(), local(false) {}
|
||||
uint64_t lastQuerySent;
|
||||
uint64_t lastResponseReceived;
|
||||
MAC mac;
|
||||
bool local;
|
||||
};
|
||||
|
||||
Hashtable<InetAddress, _NDEntry> _cache;
|
||||
uint64_t _lastCleaned;
|
||||
};
|
||||
|
||||
} // namespace ZeroTier
|
||||
|
||||
#endif
|
||||
Loading…
x
Reference in New Issue
Block a user