summaryrefslogtreecommitdiff
path: root/node/CertificateOfMembership.cpp
blob: 82e7bc8111157aa0b75048a12ff6a804bcb0e568 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
/*
 * ZeroTier One - Global Peer to Peer Ethernet
 * Copyright (C) 2012-2013  ZeroTier Networks LLC
 *
 * 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/>.
 *
 * --
 *
 * ZeroTier may be used and distributed under the terms of the GPLv3, which
 * are available at: http://www.gnu.org/licenses/gpl-3.0.html
 *
 * If you would like to embed ZeroTier into a commercial application or
 * redistribute it in a modified binary form, please contact ZeroTier Networks
 * LLC. Start here: http://www.zerotier.com/
 */

#include <algorithm>

#include "CertificateOfMembership.hpp"

namespace ZeroTier {

void CertificateOfMembership::setQualifier(uint64_t id,uint64_t value,uint64_t maxDelta)
{
	_signedBy.zero();

	for(std::vector<_Qualifier>::iterator q(_qualifiers.begin());q!=_qualifiers.end();++q) {
		if (q->id == id) {
			q->value = value;
			q->maxDelta = maxDelta;
			return;
		}
	}

	_qualifiers.push_back(_Qualifier(id,value,maxDelta));
	std::sort(_qualifiers.begin(),_qualifiers.end());
}

std::string CertificateOfMembership::toString() const
{
	std::string s;

	s.append("1:"); // COM_UINT64_ED25519

	uint64_t *buf = new uint64_t[_qualifiers.size() * 3];
	try {
		unsigned int ptr = 0;
		for(std::vector<_Qualifier>::const_iterator q(_qualifiers.begin());q!=_qualifiers.end();++q) {
			buf[ptr++] = Utils::hton(q->id);
			buf[ptr++] = Utils::hton(q->value);
			buf[ptr++] = Utils::hton(q->maxDelta);
		}
		s.append(Utils::hex(buf,ptr * sizeof(uint64_t)));
		delete [] buf;
	} catch ( ... ) {
		delete [] buf;
		throw;
	}

	s.push_back(':');

	s.append(_signedBy.toString());

	if (_signedBy) {
		s.push_back(':');
		s.append(Utils::hex(_signature.data,_signature.size()));
	}

	return s;
}

void CertificateOfMembership::fromString(const char *s)
{
	_qualifiers.clear();
	_signedBy.zero();
	memset(_signature.data,0,_signature.size());

	unsigned int colonAt = 0;
	while ((s[colonAt])&&(s[colonAt] != ':')) ++colonAt;

	if (!((colonAt == 1)&&(s[0] == '1'))) // COM_UINT64_ED25519?
		return;

	s += colonAt + 1;
	colonAt = 0;
	while ((s[colonAt])&&(s[colonAt] != ':')) ++colonAt;

	if (colonAt) {
		unsigned int buflen = colonAt / 2;
		char *buf = new char[buflen];
		unsigned int bufactual = Utils::unhex(s,colonAt,buf,buflen);
		char *bufptr = buf;
		try {
			while (bufactual >= 24) {
				_qualifiers.push_back(_Qualifier());
				_qualifiers.back().id = Utils::ntoh(*((uint64_t *)bufptr)); bufptr += 8;
				_qualifiers.back().value = Utils::ntoh(*((uint64_t *)bufptr)); bufptr += 8;
				_qualifiers.back().maxDelta = Utils::ntoh(*((uint64_t *)bufptr)); bufptr += 8;
				bufactual -= 24;
			}
		} catch ( ... ) {}
		delete [] buf;
	}

	if (s[colonAt]) {
		s += colonAt + 1;
		colonAt = 0;
		while ((s[colonAt])&&(s[colonAt] != ':')) ++colonAt;

		if (colonAt) {
			char addrbuf[ZT_ADDRESS_LENGTH];
			if (Utils::unhex(s,colonAt,addrbuf,sizeof(addrbuf)) == ZT_ADDRESS_LENGTH)
				_signedBy.setTo(addrbuf,ZT_ADDRESS_LENGTH);

			if ((_signedBy)&&(s[colonAt])) {
				s += colonAt + 1;
				colonAt = 0;
				while ((s[colonAt])&&(s[colonAt] != ':')) ++colonAt;

				if (colonAt) {
					if (Utils::unhex(s,colonAt,_signature.data,_signature.size()) != _signature.size())
						_signedBy.zero();
				} else _signedBy.zero();
			} else _signedBy.zero();
		}
	}

	std::sort(_qualifiers.begin(),_qualifiers.end());
	std::unique(_qualifiers.begin(),_qualifiers.end());
}

bool CertificateOfMembership::agreesWith(const CertificateOfMembership &other) const
	throw()
{
	unsigned long myidx = 0;
	unsigned long otheridx = 0;

	while (myidx < _qualifiers.size()) {
		// Fail if we're at the end of other, since this means the field is
		// missing.
		if (otheridx >= other._qualifiers.size())
			return false;

		// Seek to corresponding tuple in other, ignoring tuples that
		// we may not have. If we run off the end of other, the tuple is
		// missing. This works because tuples are sorted by ID.
		while (other._qualifiers[otheridx].id != _qualifiers[myidx].id) {
			++otheridx;
			if (otheridx >= other._qualifiers.size())
				return false;
		}

		// Compare to determine if the absolute value of the difference
		// between these two parameters is within our maxDelta.
		const uint64_t a = _qualifiers[myidx].value;
		const uint64_t b = other._qualifiers[myidx].value;
		if (((a >= b) ? (a - b) : (b - a)) > _qualifiers[myidx].maxDelta)
			return false;

		++myidx;
	}

	return true;
}

bool CertificateOfMembership::sign(const Identity &with)
{
	uint64_t *buf = new uint64_t[_qualifiers.size() * 3];
	unsigned int ptr = 0;
	for(std::vector<_Qualifier>::const_iterator q(_qualifiers.begin());q!=_qualifiers.end();++q) {
		buf[ptr++] = Utils::hton(q->id);
		buf[ptr++] = Utils::hton(q->value);
		buf[ptr++] = Utils::hton(q->maxDelta);
	}

	try {
		_signature = with.sign(buf,ptr * sizeof(uint64_t));
		_signedBy = with.address();
		delete [] buf;
		return true;
	} catch ( ... ) {
		_signedBy.zero();
		delete [] buf;
		return false;
	}
}

bool CertificateOfMembership::verify(const Identity &id) const
{
	if (!_signedBy)
		return false;
	if (id.address() != _signedBy)
		return false;

	uint64_t *buf = new uint64_t[_qualifiers.size() * 3];
	unsigned int ptr = 0;
	for(std::vector<_Qualifier>::const_iterator q(_qualifiers.begin());q!=_qualifiers.end();++q) {
		buf[ptr++] = Utils::hton(q->id);
		buf[ptr++] = Utils::hton(q->value);
		buf[ptr++] = Utils::hton(q->maxDelta);
	}

	bool valid = false;
	try {
		valid = id.verify(buf,ptr * sizeof(uint64_t),_signature);
		delete [] buf;
	} catch ( ... ) {
		delete [] buf;
	}
	return valid;
}

} // namespace ZeroTier