ZeroTierOne/node/Membership.hpp
2016-08-04 09:02:35 -07:00

237 lines
6.5 KiB
C++

/*
* 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_MEMBERSHIP_HPP
#define ZT_MEMBERSHIP_HPP
#include <stdint.h>
#include <utility>
#include <algorithm>
#include "Constants.hpp"
#include "../include/ZeroTierOne.h"
#include "CertificateOfMembership.hpp"
#include "Capability.hpp"
#include "Tag.hpp"
#include "Hashtable.hpp"
#include "NetworkConfig.hpp"
// Expiration time for capability and tag cache
#define ZT_MEMBERSHIP_STATE_EXPIRATION_TIME (ZT_NETWORK_COM_DEFAULT_REVISION_MAX_DELTA * 4)
// Expiration time for Memberships (used in Peer::clean())
#define ZT_MEMBERSHIP_EXPIRATION_TIME (ZT_MEMBERSHIP_STATE_EXPIRATION_TIME * 4)
namespace ZeroTier {
class Peer;
class RuntimeEnvironment;
/**
* Information related to a peer's participation on a network
*
* This structure is not thread-safe and must be locked during use.
*/
class Membership
{
private:
struct TState
{
TState() : lastPushed(0),lastReceived(0) {}
// Last time we pushed this tag to this peer
uint64_t lastPushed;
// Last time we received this tag from this peer
uint64_t lastReceived;
// Tag from peer
Tag tag;
};
struct CState
{
CState() : lastPushed(0),lastReceived(0) {}
// Last time we pushed this capability to this peer
uint64_t lastPushed;
// Last time we received this capability from this peer
uint64_t lastReceived;
// Capability from peer
Capability cap;
};
public:
Membership() :
_lastPushedCom(0),
_com(),
_caps(8),
_tags(8)
{
}
/**
* Send COM and other credentials to this peer if needed
*
* This checks last pushed times for our COM and for other credentials and
* sends VERB_NETWORK_CREDENTIALS if the recipient might need them.
*
* @param RR Runtime environment
* @param now Current time
* @param peer Peer that "owns" this membership
* @param nconf Network configuration
* @param capIds Capability IDs that this peer might need
* @param capCount Number of capability IDs
* @param tagIds Tag IDs that this peer might need
* @param tagCount Number of tag IDs
* @return True if we pushed something
*/
bool sendCredentialsIfNeeded(const RuntimeEnvironment *RR,const uint64_t now,const Peer &peer,const NetworkConfig &nconf,const uint32_t *capIds,const unsigned int capCount,const uint32_t *tagIds,const unsigned int tagCount) const;
/**
* @param nconf Network configuration
* @param id Tag ID
* @return Pointer to tag or NULL if not found
*/
inline const Tag *getTag(const NetworkConfig &nconf,const uint32_t id) const
{
const TState *t = _tags.get(id);
return ((t) ? (((t->lastReceived != 0)&&(t->tag.expiration() < nconf.timestamp)) ? &(t->tag) : (const Tag *)0) : (const Tag *)0);
}
/**
* @param nconf Network configuration
* @param id Capablity ID
* @return Pointer to capability or NULL if not found
*/
inline const Capability *getCapability(const NetworkConfig &nconf,const uint32_t id) const
{
const CState *c = _caps.get(id);
return ((c) ? (((c->lastReceived != 0)&&(c->cap.expiration() < nconf.timestamp)) ? &(c->cap) : (const Capability *)0) : (const Capability *)0);
}
/**
* Validate and add a credential if signature is okay and it's otherwise good
*
* @return 0 == OK, 1 == waiting for WHOIS, -1 == BAD signature or credential
*/
inline int addCredential(const RuntimeEnvironment *RR,const uint64_t now,const CertificateOfMembership &com)
{
if (com.issuedTo() != RR->identity.address())
return -1;
if (_com == com)
return 0;
const int vr = com.verify(RR);
if (vr == 0)
_com = com;
return vr;
}
/**
* Validate and add a credential if signature is okay and it's otherwise good
*
* @return 0 == OK, 1 == waiting for WHOIS, -1 == BAD signature or credential
*/
inline int addCredential(const RuntimeEnvironment *RR,const uint64_t now,const Tag &tag)
{
if (tag.issuedTo() != RR->identity.address())
return -1;
TState *t = _tags.get(tag.networkId());
if ((t)&&(t->lastReceived != 0)&&(t->tag == tag))
return 0;
const int vr = tag.verify(RR);
if (vr == 0) {
if (!t)
t = &(_tags[tag.networkId()]);
t->lastReceived = now;
t->tag = tag;
}
return vr;
}
/**
* Validate and add a credential if signature is okay and it's otherwise good
*
* @return 0 == OK, 1 == waiting for WHOIS, -1 == BAD signature or credential
*/
inline int addCredential(const RuntimeEnvironment *RR,const uint64_t now,const Capability &cap)
{
if (!cap.wasIssuedTo(RR->identity.address()))
return -1;
CState *c = _caps.get(cap.networkId());
if ((c)&&(c->lastReceived != 0)&&(c->cap == cap))
return 0;
const int vr = cap.verify(RR);
if (vr == 0) {
if (!c)
c = &(_caps[cap.networkId()]);
c->lastReceived = now;
c->cap = cap;
}
return vr;
}
/**
* Clean up old or stale entries
*
* @return Time of most recent activity in this Membership
*/
inline uint64_t clean(const uint64_t now)
{
uint64_t lastAct = _lastPushedCom;
uint32_t *i = (uint32_t *)0;
CState *cs = (CState *)0;
Hashtable<uint32_t,CState>::Iterator csi(_caps);
while (csi.next(i,cs)) {
const uint64_t la = std::max(cs->lastPushed,cs->lastReceived);
if ((now - la) > ZT_MEMBERSHIP_STATE_EXPIRATION_TIME)
_caps.erase(*i);
else if (la > lastAct)
lastAct = la;
}
i = (uint32_t *)0;
TState *ts = (TState *)0;
Hashtable<uint32_t,TState>::Iterator tsi(_tags);
while (tsi.next(i,ts)) {
const uint64_t la = std::max(ts->lastPushed,ts->lastReceived);
if ((now - la) > ZT_MEMBERSHIP_STATE_EXPIRATION_TIME)
_tags.erase(*i);
else if (la > lastAct)
lastAct = la;
}
return lastAct;
}
private:
// Last time we pushed our COM to this peer
uint64_t _lastPushedCom;
// COM from this peer
CertificateOfMembership _com;
// Capability-related state
Hashtable<uint32_t,CState> _caps;
// Tag-related state
Hashtable<uint32_t,TState> _tags;
};
} // namespace ZeroTier
#endif