1
2 /*
3 * Copyright (c) 2017, The OpenThread Authors.
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the copyright holder nor the
14 * names of its contributors may be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
18 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
21 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27 * POSSIBILITY OF SUCH DAMAGE.
28 */
29
30 /**
31 * @file
32 * This file implements common MeshCoP utility functions.
33 */
34
35 #include "meshcop.hpp"
36 #include <openthread/platform/toolchain.h>
37
38 #include "common/clearable.hpp"
39 #include "common/crc16.hpp"
40 #include "common/debug.hpp"
41 #include "common/locator_getters.hpp"
42 #include "common/string.hpp"
43 #include "crypto/sha256.hpp"
44 #include "mac/mac_types.hpp"
45 #include "thread/thread_netif.hpp"
46
47 namespace ot {
48
49 RegisterLogModule("MeshCoP");
50
51 namespace MeshCoP {
52
SetFrom(const char * aPskdString)53 Error JoinerPskd::SetFrom(const char *aPskdString)
54 {
55 Error error = kErrorNone;
56
57 VerifyOrExit(IsPskdValid(aPskdString), error = kErrorInvalidArgs);
58
59 Clear();
60 memcpy(m8, aPskdString, StringLength(aPskdString, sizeof(m8)));
61
62 exit:
63 return error;
64 }
65
operator ==(const JoinerPskd & aOther) const66 bool JoinerPskd::operator==(const JoinerPskd &aOther) const
67 {
68 bool isEqual = true;
69
70 for (size_t i = 0; i < sizeof(m8); i++)
71 {
72 if (m8[i] != aOther.m8[i])
73 {
74 isEqual = false;
75 ExitNow();
76 }
77
78 if (m8[i] == '\0')
79 {
80 break;
81 }
82 }
83
84 exit:
85 return isEqual;
86 }
87
IsPskdValid(const char * aPskdString)88 bool JoinerPskd::IsPskdValid(const char *aPskdString)
89 {
90 bool valid = false;
91 uint16_t pskdLength = StringLength(aPskdString, kMaxLength + 1);
92
93 VerifyOrExit(pskdLength >= kMinLength && pskdLength <= kMaxLength);
94
95 for (uint16_t i = 0; i < pskdLength; i++)
96 {
97 char c = aPskdString[i];
98
99 VerifyOrExit(IsDigit(c) || IsUppercase(c));
100 VerifyOrExit(c != 'I' && c != 'O' && c != 'Q' && c != 'Z');
101 }
102
103 valid = true;
104
105 exit:
106 return valid;
107 }
108
GenerateJoinerId(Mac::ExtAddress & aJoinerId) const109 void JoinerDiscerner::GenerateJoinerId(Mac::ExtAddress &aJoinerId) const
110 {
111 aJoinerId.GenerateRandom();
112 CopyTo(aJoinerId);
113 aJoinerId.SetLocal(true);
114 }
115
Matches(const Mac::ExtAddress & aJoinerId) const116 bool JoinerDiscerner::Matches(const Mac::ExtAddress &aJoinerId) const
117 {
118 uint64_t mask;
119
120 OT_ASSERT(IsValid());
121
122 mask = GetMask();
123
124 return (BigEndian::ReadUint64(aJoinerId.m8) & mask) == (mValue & mask);
125 }
126
CopyTo(Mac::ExtAddress & aExtAddress) const127 void JoinerDiscerner::CopyTo(Mac::ExtAddress &aExtAddress) const
128 {
129 // Copies the discerner value up to its bit length to `aExtAddress`
130 // array, assuming big-endian encoding (i.e., the discerner lowest bits
131 // are copied at end of `aExtAddress.m8[]` array). Any initial/remaining
132 // bits of `aExtAddress` array remain unchanged.
133
134 uint8_t *cur = &aExtAddress.m8[sizeof(Mac::ExtAddress) - 1];
135 uint8_t remaining = mLength;
136 uint64_t value = mValue;
137
138 OT_ASSERT(IsValid());
139
140 // Write full bytes
141 while (remaining >= kBitsPerByte)
142 {
143 *cur = static_cast<uint8_t>(value & 0xff);
144 value >>= kBitsPerByte;
145 cur--;
146 remaining -= kBitsPerByte;
147 }
148
149 // Write any remaining bits (not a full byte)
150 if (remaining != 0)
151 {
152 uint8_t mask = static_cast<uint8_t>((1U << remaining) - 1);
153
154 // `mask` has it lower (lsb) `remaining` bits as `1` and rest as `0`.
155 // Example with `remaining = 3` -> (1 << 3) - 1 = 0b1000 - 1 = 0b0111.
156
157 *cur &= ~mask;
158 *cur |= static_cast<uint8_t>(value & mask);
159 }
160 }
161
operator ==(const JoinerDiscerner & aOther) const162 bool JoinerDiscerner::operator==(const JoinerDiscerner &aOther) const
163 {
164 uint64_t mask = GetMask();
165
166 return IsValid() && (mLength == aOther.mLength) && ((mValue & mask) == (aOther.mValue & mask));
167 }
168
ToString(void) const169 JoinerDiscerner::InfoString JoinerDiscerner::ToString(void) const
170 {
171 InfoString string;
172
173 if (mLength <= BitSizeOf(uint16_t))
174 {
175 string.Append("0x%04x", static_cast<uint16_t>(mValue));
176 }
177 else if (mLength <= BitSizeOf(uint32_t))
178 {
179 string.Append("0x%08lx", ToUlong(static_cast<uint32_t>(mValue)));
180 }
181 else
182 {
183 string.Append("0x%lx-%08lx", ToUlong(static_cast<uint32_t>(mValue >> 32)),
184 ToUlong(static_cast<uint32_t>(mValue)));
185 }
186
187 string.Append("/len:%d", mLength);
188
189 return string;
190 }
191
Init(uint8_t aLength)192 void SteeringData::Init(uint8_t aLength)
193 {
194 OT_ASSERT(aLength <= kMaxLength);
195 mLength = aLength;
196 ClearAllBytes(m8);
197 }
198
SetToPermitAllJoiners(void)199 void SteeringData::SetToPermitAllJoiners(void)
200 {
201 Init(1);
202 m8[0] = kPermitAll;
203 }
204
UpdateBloomFilter(const Mac::ExtAddress & aJoinerId)205 void SteeringData::UpdateBloomFilter(const Mac::ExtAddress &aJoinerId)
206 {
207 HashBitIndexes indexes;
208
209 CalculateHashBitIndexes(aJoinerId, indexes);
210 UpdateBloomFilter(indexes);
211 }
212
UpdateBloomFilter(const JoinerDiscerner & aDiscerner)213 void SteeringData::UpdateBloomFilter(const JoinerDiscerner &aDiscerner)
214 {
215 HashBitIndexes indexes;
216
217 CalculateHashBitIndexes(aDiscerner, indexes);
218 UpdateBloomFilter(indexes);
219 }
220
UpdateBloomFilter(const HashBitIndexes & aIndexes)221 void SteeringData::UpdateBloomFilter(const HashBitIndexes &aIndexes)
222 {
223 OT_ASSERT((mLength > 0) && (mLength <= kMaxLength));
224
225 SetBit(aIndexes.mIndex[0] % GetNumBits());
226 SetBit(aIndexes.mIndex[1] % GetNumBits());
227 }
228
Contains(const Mac::ExtAddress & aJoinerId) const229 bool SteeringData::Contains(const Mac::ExtAddress &aJoinerId) const
230 {
231 HashBitIndexes indexes;
232
233 CalculateHashBitIndexes(aJoinerId, indexes);
234
235 return Contains(indexes);
236 }
237
Contains(const JoinerDiscerner & aDiscerner) const238 bool SteeringData::Contains(const JoinerDiscerner &aDiscerner) const
239 {
240 HashBitIndexes indexes;
241
242 CalculateHashBitIndexes(aDiscerner, indexes);
243
244 return Contains(indexes);
245 }
246
Contains(const HashBitIndexes & aIndexes) const247 bool SteeringData::Contains(const HashBitIndexes &aIndexes) const
248 {
249 return (mLength > 0) && GetBit(aIndexes.mIndex[0] % GetNumBits()) && GetBit(aIndexes.mIndex[1] % GetNumBits());
250 }
251
CalculateHashBitIndexes(const Mac::ExtAddress & aJoinerId,HashBitIndexes & aIndexes)252 void SteeringData::CalculateHashBitIndexes(const Mac::ExtAddress &aJoinerId, HashBitIndexes &aIndexes)
253 {
254 Crc16 ccitt(Crc16::kCcitt);
255 Crc16 ansi(Crc16::kAnsi);
256
257 for (uint8_t b : aJoinerId.m8)
258 {
259 ccitt.Update(b);
260 ansi.Update(b);
261 }
262
263 aIndexes.mIndex[0] = ccitt.Get();
264 aIndexes.mIndex[1] = ansi.Get();
265 }
266
CalculateHashBitIndexes(const JoinerDiscerner & aDiscerner,HashBitIndexes & aIndexes)267 void SteeringData::CalculateHashBitIndexes(const JoinerDiscerner &aDiscerner, HashBitIndexes &aIndexes)
268 {
269 Mac::ExtAddress address;
270
271 address.Clear();
272 aDiscerner.CopyTo(address);
273
274 CalculateHashBitIndexes(address, aIndexes);
275 }
276
DoesAllMatch(uint8_t aMatch) const277 bool SteeringData::DoesAllMatch(uint8_t aMatch) const
278 {
279 bool matches = true;
280
281 for (uint8_t i = 0; i < mLength; i++)
282 {
283 if (m8[i] != aMatch)
284 {
285 matches = false;
286 break;
287 }
288 }
289
290 return matches;
291 }
292
ComputeJoinerId(const Mac::ExtAddress & aEui64,Mac::ExtAddress & aJoinerId)293 void ComputeJoinerId(const Mac::ExtAddress &aEui64, Mac::ExtAddress &aJoinerId)
294 {
295 Crypto::Sha256 sha256;
296 Crypto::Sha256::Hash hash;
297
298 sha256.Start();
299 sha256.Update(aEui64);
300 sha256.Finish(hash);
301
302 memcpy(&aJoinerId, hash.GetBytes(), sizeof(aJoinerId));
303 aJoinerId.SetLocal(true);
304 }
305
306 #if OPENTHREAD_FTD
GeneratePskc(const char * aPassPhrase,const NetworkName & aNetworkName,const ExtendedPanId & aExtPanId,Pskc & aPskc)307 Error GeneratePskc(const char *aPassPhrase,
308 const NetworkName &aNetworkName,
309 const ExtendedPanId &aExtPanId,
310 Pskc &aPskc)
311 {
312 Error error = kErrorNone;
313 const char saltPrefix[] = "Thread";
314 uint8_t salt[OT_CRYPTO_PBDKF2_MAX_SALT_SIZE];
315 uint16_t saltLen = 0;
316 uint16_t passphraseLen;
317 uint8_t networkNameLen;
318
319 VerifyOrExit(IsValidUtf8String(aPassPhrase), error = kErrorInvalidArgs);
320
321 passphraseLen = static_cast<uint16_t>(StringLength(aPassPhrase, OT_COMMISSIONING_PASSPHRASE_MAX_SIZE + 1));
322 networkNameLen = static_cast<uint8_t>(StringLength(aNetworkName.GetAsCString(), OT_NETWORK_NAME_MAX_SIZE + 1));
323
324 VerifyOrExit((passphraseLen >= OT_COMMISSIONING_PASSPHRASE_MIN_SIZE) &&
325 (passphraseLen <= OT_COMMISSIONING_PASSPHRASE_MAX_SIZE) &&
326 (networkNameLen <= OT_NETWORK_NAME_MAX_SIZE),
327 error = kErrorInvalidArgs);
328
329 ClearAllBytes(salt);
330 memcpy(salt, saltPrefix, sizeof(saltPrefix) - 1);
331 saltLen += static_cast<uint16_t>(sizeof(saltPrefix) - 1);
332
333 memcpy(salt + saltLen, aExtPanId.m8, sizeof(aExtPanId));
334 saltLen += OT_EXT_PAN_ID_SIZE;
335
336 memcpy(salt + saltLen, aNetworkName.GetAsCString(), networkNameLen);
337 saltLen += networkNameLen;
338
339 error = otPlatCryptoPbkdf2GenerateKey(reinterpret_cast<const uint8_t *>(aPassPhrase), passphraseLen, salt, saltLen,
340 16384, OT_PSKC_MAX_SIZE, aPskc.m8);
341
342 exit:
343 return error;
344 }
345 #endif // OPENTHREAD_FTD
346
347 } // namespace MeshCoP
348 } // namespace ot
349