/*
* 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_CAPABILITY_HPP
#define ZT_CAPABILITY_HPP
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "Constants.hpp"
#include "Credential.hpp"
#include "Address.hpp"
#include "C25519.hpp"
#include "Utils.hpp"
#include "Buffer.hpp"
#include "Identity.hpp"
#include "../include/ZeroTierOne.h"
namespace ZeroTier {
class RuntimeEnvironment;
/**
* A set of grouped and signed network flow rules
*
* On the sending side the sender does the following for each packet:
*
* (1) Evaluates its capabilities in ascending order of ID to determine
* which capability allows it to transmit this packet.
* (2) If it has not done so lately, it then sends this capability to the
* receving peer ("presents" it).
* (3) The sender then sends the packet.
*
* On the receiving side the receiver evaluates the capabilities presented
* by the sender. If any valid un-expired capability allows this packet it
* is accepted.
*
* Note that this is after evaluation of network scope rules and only if
* network scope rules do not deliver an explicit match.
*
* Capabilities support a chain of custody. This is currently unused but
* in the future would allow the publication of capabilities that can be
* handed off between nodes. Limited transferrability of capabilities is
* a feature of true capability based security.
*/
class Capability : public Credential
{
public:
static inline Credential::Type credentialType() { return Credential::CREDENTIAL_TYPE_CAPABILITY; }
Capability()
{
memset(this,0,sizeof(Capability));
}
/**
* @param id Capability ID
* @param nwid Network ID
* @param ts Timestamp (at controller)
* @param mccl Maximum custody chain length (1 to create non-transferrable capability)
* @param rules Network flow rules for this capability
* @param ruleCount Number of flow rules
*/
Capability(uint32_t id,uint64_t nwid,uint64_t ts,unsigned int mccl,const ZT_VirtualNetworkRule *rules,unsigned int ruleCount)
{
memset(this,0,sizeof(Capability));
_nwid = nwid;
_ts = ts;
_id = id;
_maxCustodyChainLength = (mccl > 0) ? ((mccl < ZT_MAX_CAPABILITY_CUSTODY_CHAIN_LENGTH) ? mccl : (unsigned int)ZT_MAX_CAPABILITY_CUSTODY_CHAIN_LENGTH) : 1;
_ruleCount = (ruleCount < ZT_MAX_CAPABILITY_RULES) ? ruleCount : ZT_MAX_CAPABILITY_RULES;
if (_ruleCount)
memcpy(_rules,rules,sizeof(ZT_VirtualNetworkRule) * _ruleCount);
}
/**
* @return Rules -- see ruleCount() for size of array
*/
inline const ZT_VirtualNetworkRule *rules() const { return _rules; }
/**
* @return Number of rules in rules()
*/
inline unsigned int ruleCount() const { return _ruleCount; }
/**
* @return ID and evaluation order of this capability in network
*/
inline uint32_t id() const { return _id; }
/**
* @return Network ID for which this capability was issued
*/
inline uint64_t networkId() const { return _nwid; }
/**
* @return Timestamp
*/
inline uint64_t timestamp() const { return _ts; }
/**
* @return Last 'to' address in chain of custody
*/
inline Address issuedTo() const
{
Address i2;
for(unsigned int i=0;i<ZT_MAX_CAPABILITY_CUSTODY_CHAIN_LENGTH;++i) {
if (!_custody[i].to)
return i2;
else i2 = _custody[i].to;
}
return i2;
}
/**
* Sign this capability and add signature to its chain of custody
*
* If this returns false, this object should be considered to be
* in an undefined state and should be discarded. False can be returned
* if there is no more room for signatures (max chain length reached)
* or if the 'from' identity does not include a secret key to allow
* it to sign anything.
*
* @param from Signing identity (must have secret)
* @param to Recipient of this signature
* @return True if signature successful and chain of custody appended
*/
inline bool sign(const Identity &from,const Address &to)
{
try {
for(unsigned int i=0;((i<_maxCustodyChainLength)&&(i<ZT_MAX_CAPABILITY_CUSTODY_CHAIN_LENGTH));++i) {
if (!(_custody[i].to)) {
Buffer<(sizeof(Capability) * 2)> tmp;
this->serialize(tmp,true);
_custody[i].to = to;
_custody[i].from = from.address();
_custody[i].signature = from.sign(tmp.data(),tmp.size());
return true;
}
}
} catch ( ... ) {}
return false;
}
/**
* Verify this capability's chain of custody and signatures
*
* @param RR Runtime environment to provide for peer lookup, etc.
* @return 0 == OK, 1 == waiting for WHOIS, -1 == BAD signature or chain
*/
int verify(const RuntimeEnvironment *RR,void *tPtr) const;
template<unsigned int C>
static inline void serializeRules(Buffer<C> &b,const ZT_VirtualNetworkRule *rules,unsigned int ruleCount)
{
for(unsigned int i=0;i<ruleCount;++i) {
// Each rule consists of its 8-bit type followed by the size of that type's
// field followed by field data. The inclusion of the size will allow non-supported
// rules to be ignored but still parsed.
b.append((uint8_t)rules[i].t);
switch((ZT_VirtualNetworkRuleType)(rules[i].t & 0x3f)) {
default:
b.append((uint8_t)0);
break;
case ZT_NETWORK_RULE_ACTION_TEE:
case ZT_NETWORK_RULE_ACTION_WATCH:
case ZT_NETWORK_RULE_ACTION_REDIRECT:
b.append((uint8_t)14);
b.append((uint64_t)rules[i].v.fwd.address);
b.append((uint32_t)rules[i].v.fwd.flags);
b.append((uint16_t)rules[i].v.fwd.length); // unused for redirect
break;
case ZT_NETWORK_RULE_MATCH_SOURCE_ZEROTIER_ADDRESS:
case ZT_NETWORK_RULE_MATCH_DEST_ZEROTIER_ADDRESS:
b.append((uint8_t)5);
Address(rules[i].v.zt).appendTo(b);
break;
case ZT_NETWORK_RULE_MATCH_VLAN_ID:
b.append((uint8_t)2);
b.append((uint16_t)rules[i].v.vlanId);
break;
case ZT_NETWORK_RULE_MATCH_VLAN_PCP:
b.append((uint8_t)1);
b.append((uint8_t)rules[i].v.vlanPcp);
break;
case ZT_NETWORK_RULE_MATCH_VLAN_DEI:
b.append((uint8_t)1);
b.append((uint8_t)rules[i].v.vlanDei);
break;
case ZT_NETWORK_RULE_MATCH_MAC_SOURCE:
case ZT_NETWORK_RULE_MATCH_MAC_DEST:
b.append((uint8_t)6);
b.append(rules[i].v.mac,6);
break;
case ZT_NETWORK_RULE_MATCH_IPV4_SOURCE:
case ZT_NETWORK_RULE_MATCH_IPV4_DEST:
b.append((uint8_t)5);
b.append(&(rules[i].v.ipv4.ip),4);
b.append((uint8_t)rules[i].v.ipv4.mask);
break;
case ZT_NETWORK_RULE_MATCH_IPV6_SOURCE:
case ZT_NETWORK_RULE_MATCH_IPV6_DEST:
b.append((uint8_t)17);
b.append(rules[i].v.ipv6.ip,16);
b.append((uint8_t)rules[i].v.ipv6.mask);
break;
case ZT_NETWORK_RULE_MATCH_IP_TOS:
b.append((uint8_t)3);
b.append((uint8_t)rules[i].v.ipTos.mask);
b.append((uint8_t)rules[i].v.ipTos.value[0]);
b.append((uint8_t)rules[i].v.ipTos.value[1]);
break;
case ZT_NETWORK_RULE_MATCH_IP_PROTOCOL:
b.append((uint8_t)1);
b.append((uint8_t)rules[i].v.ipProtocol);
break;
case ZT_NETWORK_RULE_MATCH_ETHERTYPE:
b.append((uint8_t)2);
b.append((uint16_t)rules[i].v.etherType);
break;
case ZT_NETWORK_RULE_MATCH_ICMP:
b.append((uint8_t)3);
b.append((uint8_t)rules[i].v.icmp.type);
b.append((uint8_t)rules[i].v.icmp.code);
b.append((uint8_t)rules[i].v.icmp.flags);
break;
case ZT_NETWORK_RULE_MATCH_IP_SOURCE_PORT_RANGE:
case ZT_NETWORK_RULE_MATCH_IP_DEST_PORT_RANGE:
b.append((uint8_t)4);
b.append((uint16_t)rules[i].v.port[0]);
b.append((uint16_t)rules[i].v.port[1]);
break;
case ZT_NETWORK_RULE_MATCH_CHARACTERISTICS:
b.append((uint8_t)8);
b.append((uint64_t)rules[i].v.characteristics);
break;
case ZT_NETWORK_RULE_MATCH_FRAME_SIZE_RANGE:
b.append((uint8_t)4);
b.append((uint16_t)rules[i].v.frameSize[0]);
b.append((uint16_t)rules[i].v.frameSize[1]);
break;
case ZT_NETWORK_RULE_MATCH_RANDOM:
b.append((uint8_t)4);
b.append((uint32_t)rules[i].v.randomProbability);
break;
case ZT_NETWORK_RULE_MATCH_TAGS_DIFFERENCE:
case ZT_NETWORK_RULE_MATCH_TAGS_BITWISE_AND:
case ZT_NETWORK_RULE_MATCH_TAGS_BITWISE_OR:
case ZT_NETWORK_RULE_MATCH_TAGS_BITWISE_XOR:
case ZT_NETWORK_RULE_MATCH_TAGS_EQUAL:
case ZT_NETWORK_RULE_MATCH_TAG_SENDER:
case ZT_NETWORK_RULE_MATCH_TAG_RECEIVER:
b.append((uint8_t)8);
b.append((uint32_t)rules[i].v.tag.id);
b.append((uint32_t)rules[i].v.tag.value);
break;
}
}
}
template<unsigned int C>
static inline void deserializeRules(const Buffer<C> &b,unsigned int &p,ZT_VirtualNetworkRule *rules,unsigned int &ruleCount,const unsigned int maxRuleCount)
{
while ((ruleCount < maxRuleCount)&&(p < b.size())) {
rules[ruleCount].t = (uint8_t)b[p++];
const unsigned int fieldLen = (unsigned int)b[p++];
switch((ZT_VirtualNetworkRuleType)(rules[ruleCount].t & 0x3f)) {
default:
break;
case ZT_NETWORK_RULE_ACTION_TEE:
case ZT_NETWORK_RULE_ACTION_WATCH:
case ZT_NETWORK_RULE_ACTION_REDIRECT:
rules[ruleCount].v.fwd.address = b.template at<uint64_t>(p);
rules[ruleCount].v.fwd.flags = b.template at<uint32_t>(p + 8);
rules[ruleCount].v.fwd.length = b.template at<uint16_t>(p + 12);
break;
case ZT_NETWORK_RULE_MATCH_SOURCE_ZEROTIER_ADDRESS:
case ZT_NETWORK_RULE_MATCH_DEST_ZEROTIER_ADDRESS:
rules[ruleCount].v.zt = Address(b.field(p,ZT_ADDRESS_LENGTH),ZT_ADDRESS_LENGTH).toInt();
break;
case ZT_NETWORK_RULE_MATCH_VLAN_ID:
rules[ruleCount].v.vlanId = b.template at<uint16_t>(p);
break;
case ZT_NETWORK_RULE_MATCH_VLAN_PCP:
rules[ruleCount].v.vlanPcp = (uint8_t)b[p];
break;
case ZT_NETWORK_RULE_MATCH_VLAN_DEI:
rules[ruleCount].v.vlanDei = (uint8_t)b[p];
break;
case ZT_NETWORK_RULE_MATCH_MAC_SOURCE:
case ZT_NETWORK_RULE_MATCH_MAC_DEST:
memcpy(rules[ruleCount].v.mac,b.field(p,6),6);
break;
case ZT_NETWORK_RULE_MATCH_IPV4_SOURCE:
case ZT_NETWORK_RULE_MATCH_IPV4_DEST:
memcpy(&(rules[ruleCount].v.ipv4.ip),b.field(p,4),4);
rules[ruleCount].v.ipv4.mask = (uint8_t)b[p + 4];
break;
case ZT_NETWORK_RULE_MATCH_IPV6_SOURCE:
case ZT_NETWORK_RULE_MATCH_IPV6_DEST:
memcpy(rules[ruleCount].v.ipv6.ip,b.field(p,16),16);
rules[ruleCount].v.ipv6.mask = (uint8_t)b[p + 16];
break;
case ZT_NETWORK_RULE_MATCH_IP_TOS:
rules[ruleCount].v.ipTos.mask = (uint8_t)b[p];
rules[ruleCount].v.ipTos.value[0] = (uint8_t)b[p+1];
rules[ruleCount].v.ipTos.value[1] = (uint8_t)b[p+2];
break;
case ZT_NETWORK_RULE_MATCH_IP_PROTOCOL:
rules[ruleCount].v.ipProtocol = (uint8_t)b[p];
break;
case ZT_NETWORK_RULE_MATCH_ETHERTYPE:
rules[ruleCount].v.etherType = b.template at<uint16_t>(p);
break;
case ZT_NETWORK_RULE_MATCH_ICMP:
rules[ruleCount].v.icmp.type = (uint8_t)b[p];
rules[ruleCount].v.icmp.code = (uint8_t)b[p+1];
rules[ruleCount].v.icmp.flags = (uint8_t)b[p+2];
break;
case ZT_NETWORK_RULE_MATCH_IP_SOURCE_PORT_RANGE:
case ZT_NETWORK_RULE_MATCH_IP_DEST_PORT_RANGE:
rules[ruleCount].v.port[0] = b.template at<uint16_t>(p);
rules[ruleCount].v.port[1] = b.template at<uint16_t>(p + 2);
break;
case ZT_NETWORK_RULE_MATCH_CHARACTERISTICS:
rules[ruleCount].v.characteristics = b.template at<uint64_t>(p);
break;
case ZT_NETWORK_RULE_MATCH_FRAME_SIZE_RANGE:
rules[ruleCount].v.frameSize[0] = b.template at<uint16_t>(p);
rules[ruleCount].v.frameSize[1] = b.template at<uint16_t>(p + 2);
break;
case ZT_NETWORK_RULE_MATCH_RANDOM:
rules[ruleCount].v.randomProbability = b.template at<uint32_t>(p);
break;
case ZT_NETWORK_RULE_MATCH_TAGS_DIFFERENCE:
case ZT_NETWORK_RULE_MATCH_TAGS_BITWISE_AND:
case ZT_NETWORK_RULE_MATCH_TAGS_BITWISE_OR:
case ZT_NETWORK_RULE_MATCH_TAGS_BITWISE_XOR:
case ZT_NETWORK_RULE_MATCH_TAGS_EQUAL:
case ZT_NETWORK_RULE_MATCH_TAG_SENDER:
case ZT_NETWORK_RULE_MATCH_TAG_RECEIVER:
rules[ruleCount].v.tag.id = b.template at<uint32_t>(p);
rules[ruleCount].v.tag.value = b.template at<uint32_t>(p + 4);
break;
}
p += fieldLen;
++ruleCount;
}
}
template<unsigned int C>
inline void serialize(Buffer<C> &b,const bool forSign = false) const
{
if (forSign) b.append((uint64_t)0x7f7f7f7f7f7f7f7fULL);
// These are the same between Tag and Capability
b.append(_nwid);
b.append(_ts);
b.append(_id);
b.append((uint16_t)_ruleCount);
serializeRules(b,_rules,_ruleCount);
b.append((uint8_t)_maxCustodyChainLength);
if (!forSign) {
for(unsigned int i=0;;++i) {
if ((i < _maxCustodyChainLength)&&(i < ZT_MAX_CAPABILITY_CUSTODY_CHAIN_LENGTH)&&(_custody[i].to)) {
_custody[i].to.appendTo(b);
_custody[i].from.appendTo(b);
b.append((uint8_t)1); // 1 == Ed25519 signature
b.append((uint16_t)ZT_C25519_SIGNATURE_LEN); // length of signature
b.append(_custody[i].signature.data,ZT_C25519_SIGNATURE_LEN);
} else {
b.append((unsigned char)0,ZT_ADDRESS_LENGTH); // zero 'to' terminates chain
break;
}
}
}
// This is the size of any additional fields, currently 0.
b.append((uint16_t)0);
if (forSign) b.append((uint64_t)0x7f7f7f7f7f7f7f7fULL);
}
template<unsigned int C>
inline unsigned int deserialize(const Buffer<C> &b,unsigned int startAt = 0)
{
memset(this,0,sizeof(Capability));
unsigned int p = startAt;
_nwid = b.template at<uint64_t>(p); p += 8;
_ts = b.template at<uint64_t>(p); p += 8;
_id = b.template at<uint32_t>(p); p += 4;
const unsigned int rc = b.template at<uint16_t>(p); p += 2;
if (rc > ZT_MAX_CAPABILITY_RULES)
throw std::runtime_error("rule overflow");
deserializeRules(b,p,_rules,_ruleCount,rc);
_maxCustodyChainLength = (unsigned int)b[p++];
if ((_maxCustodyChainLength < 1)||(_maxCustodyChainLength > ZT_MAX_CAPABILITY_CUSTODY_CHAIN_LENGTH))
throw std::runtime_error("invalid max custody chain length");
for(unsigned int i=0;;++i) {
const Address to(b.field(p,ZT_ADDRESS_LENGTH),ZT_ADDRESS_LENGTH); p += ZT_ADDRESS_LENGTH;
if (!to)
break;
if ((i >= _maxCustodyChainLength)||(i >= ZT_MAX_CAPABILITY_CUSTODY_CHAIN_LENGTH))
throw std::runtime_error("unterminated custody chain");
_custody[i].to = to;
_custody[i].from.setTo(b.field(p,ZT_ADDRESS_LENGTH),ZT_ADDRESS_LENGTH); p += ZT_ADDRESS_LENGTH;
if (b[p++] == 1) {
if (b.template at<uint16_t>(p) != ZT_C25519_SIGNATURE_LEN)
throw std::runtime_error("invalid signature");
p += 2;
memcpy(_custody[i].signature.data,b.field(p,ZT_C25519_SIGNATURE_LEN),ZT_C25519_SIGNATURE_LEN); p += ZT_C25519_SIGNATURE_LEN;
} else {
p += 2 + b.template at<uint16_t>(p);
}
}
p += 2 + b.template at<uint16_t>(p);
if (p > b.size())
throw std::runtime_error("extended field overflow");
return (p - startAt);
}
// Provides natural sort order by ID
inline bool operator<(const Capability &c) const { return (_id < c._id); }
inline bool operator==(const Capability &c) const { return (memcmp(this,&c,sizeof(Capability)) == 0); }
inline bool operator!=(const Capability &c) const { return (memcmp(this,&c,sizeof(Capability)) != 0); }
private:
uint64_t _nwid;
uint64_t _ts;
uint32_t _id;
unsigned int _maxCustodyChainLength;
unsigned int _ruleCount;
ZT_VirtualNetworkRule _rules[ZT_MAX_CAPABILITY_RULES];
struct {
Address to;
Address from;
C25519::Signature signature;
} _custody[ZT_MAX_CAPABILITY_CUSTODY_CHAIN_LENGTH];
};
} // namespace ZeroTier
#endif