Crypto++ 8.9 Free C++ class library of cryptographic schemes

gfpcrypt.h
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1 // gfpcrypt.h - originally written and placed in the public domain by Wei Dai
2 // RFC6979 deterministic signatures added by Douglas Roark
3 // ECGDSA added by Jeffrey Walton
4
5 /// \file gfpcrypt.h
6 /// \brief Classes and functions for schemes based on Discrete Logs (DL) over GF(p)
7
8 #ifndef CRYPTOPP_GFPCRYPT_H
9 #define CRYPTOPP_GFPCRYPT_H
10
11 #include "config.h"
12
13 #if CRYPTOPP_MSC_VERSION
14 # pragma warning(push)
15 # pragma warning(disable: 4189 4231 4275)
16 #endif
17
18 #include "cryptlib.h"
19 #include "pubkey.h"
20 #include "integer.h"
21 #include "modexppc.h"
22 #include "algparam.h"
23 #include "smartptr.h"
24 #include "sha.h"
25 #include "asn.h"
26 #include "hmac.h"
27 #include "misc.h"
28
29 NAMESPACE_BEGIN(CryptoPP)
30
31 CRYPTOPP_DLL_TEMPLATE_CLASS DL_GroupParameters<Integer>;
32
33 /// \brief Integer-based GroupParameters specialization
34 class CRYPTOPP_DLL CRYPTOPP_NO_VTABLE DL_GroupParameters_IntegerBased : public ASN1CryptoMaterial<DL_GroupParameters<Integer> >
35 {
36 typedef DL_GroupParameters_IntegerBased ThisClass;
37
38 public:
39 virtual ~DL_GroupParameters_IntegerBased() {}
40
41 /// \brief Initialize a group parameters over integers
42 /// \param params the group parameters
43 void Initialize(const DL_GroupParameters_IntegerBased &params)
44 {Initialize(params.GetModulus(), params.GetSubgroupOrder(), params.GetSubgroupGenerator());}
45
46 /// \brief Create a group parameters over integers
47 /// \param rng a RandomNumberGenerator derived class
48 /// \param pbits the size of p, in bits
49 /// \details This function overload of Initialize() creates a new private key because it
50 /// takes a RandomNumberGenerator() as a parameter. If you have an existing keypair,
51 /// then use one of the other Initialize() overloads.
52 void Initialize(RandomNumberGenerator &rng, unsigned int pbits)
53 {GenerateRandom(rng, MakeParameters("ModulusSize", (int)pbits));}
54
55 /// \brief Initialize a group parameters over integers
56 /// \param p the modulus
57 /// \param g the generator
58 void Initialize(const Integer &p, const Integer &g)
59 {SetModulusAndSubgroupGenerator(p, g); SetSubgroupOrder(ComputeGroupOrder(p)/2);}
60
61 /// \brief Initialize a group parameters over integers
62 /// \param p the modulus
63 /// \param q the subgroup order
64 /// \param g the generator
65 void Initialize(const Integer &p, const Integer &q, const Integer &g)
66 {SetModulusAndSubgroupGenerator(p, g); SetSubgroupOrder(q);}
67
68 // ASN1Object interface
69 void BERDecode(BufferedTransformation &bt);
70 void DEREncode(BufferedTransformation &bt) const;
71
72 /// \brief Generate a random key
73 /// \param rng a RandomNumberGenerator to produce keying material
74 /// \param alg additional initialization parameters
75 /// \details Recognised NameValuePairs are ModulusSize and
76 /// SubgroupOrderSize (optional)
77 /// \throw KeyingErr if a key can't be generated or algorithm parameters
78 /// are invalid
79 void GenerateRandom(RandomNumberGenerator &rng, const NameValuePairs &alg);
80
81 /// \brief Get a named value
82 /// \param name the name of the object or value to retrieve
83 /// \param valueType reference to a variable that receives the value
84 /// \param pValue void pointer to a variable that receives the value
85 /// \return true if the value was retrieved, false otherwise
86 /// \details GetVoidValue() retrieves the value of name if it exists.
87 /// \note GetVoidValue() is an internal function and should be implemented
88 /// by derived classes. Users should use one of the other functions instead.
89 /// \sa GetValue(), GetValueWithDefault(), GetIntValue(), GetIntValueWithDefault(),
90 /// GetRequiredParameter() and GetRequiredIntParameter()
91 bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const;
92
93 /// \brief Initialize or reinitialize this key
94 /// \param source NameValuePairs to assign
95 void AssignFrom(const NameValuePairs &source);
96
97 // DL_GroupParameters
98 const Integer & GetSubgroupOrder() const {return m_q;}
99 Integer GetGroupOrder() const {return GetFieldType() == 1 ? GetModulus()-Integer::One() : GetModulus()+Integer::One();}
100 bool ValidateGroup(RandomNumberGenerator &rng, unsigned int level) const;
101 bool ValidateElement(unsigned int level, const Integer &element, const DL_FixedBasePrecomputation<Integer> *precomp) const;
102
103 /// \brief Determine if subgroup membership check is fast
104 /// \return true or false
105 bool FastSubgroupCheckAvailable() const {return GetCofactor() == 2;}
106
107 /// \brief Encodes the element
108 /// \param reversible flag indicating the encoding format
109 /// \param element reference to the element to encode
110 /// \param encoded destination byte array for the encoded element
111 /// \details EncodeElement() must be implemented in a derived class.
112 /// \pre <tt>COUNTOF(encoded) == GetEncodedElementSize()</tt>
113 /// \sa GetEncodedElementSize(), DecodeElement(), <A
114 /// HREF="http://github.com/weidai11/cryptopp/issues/40">Cygwin
115 /// i386 crash at -O3</A>
116 void EncodeElement(bool reversible, const Element &element, byte *encoded) const;
117
118 /// \brief Retrieve the encoded element's size
119 /// \param reversible flag indicating the encoding format
120 /// \return encoded element's size, in bytes
121 /// \details The format of the encoded element varies by the underlying
122 /// type of the element and the reversible flag.
123 /// \sa EncodeElement(), DecodeElement()
124 unsigned int GetEncodedElementSize(bool reversible) const;
125
126 /// \brief Decodes the element
127 /// \param encoded byte array with the encoded element
128 /// \param checkForGroupMembership flag indicating if the element should be validated
129 /// \return Element after decoding
130 /// \details DecodeElement() must be implemented in a derived class.
131 /// \pre <tt>COUNTOF(encoded) == GetEncodedElementSize()</tt>
132 /// \sa GetEncodedElementSize(), EncodeElement()
133 Integer DecodeElement(const byte *encoded, bool checkForGroupMembership) const;
134
135 /// \brief Converts an element to an Integer
136 /// \param element the element to convert to an Integer
137 /// \return Element after converting to an Integer
138 /// \details ConvertElementToInteger() must be implemented in a derived class.
139 Integer ConvertElementToInteger(const Element &element) const
140 {return element;}
141
142 /// \brief Retrieve the maximum exponent for the group
143 /// \return the maximum exponent for the group
144 Integer GetMaxExponent() const;
145
146 /// \brief Retrieve the OID of the algorithm
147 /// \return OID of the algorithm
148 OID GetAlgorithmID() const;
149
150 /// \brief Retrieve the modulus for the group
151 /// \return the modulus for the group
152 virtual const Integer & GetModulus() const =0;
153
154 /// \brief Set group parameters
155 /// \param p the prime modulus
156 /// \param g the group generator
157 virtual void SetModulusAndSubgroupGenerator(const Integer &p, const Integer &g) =0;
158
159 /// \brief Set subgroup order
160 /// \param q the subgroup order
161 void SetSubgroupOrder(const Integer &q)
162 {m_q = q; ParametersChanged();}
163
164 static std::string CRYPTOPP_API StaticAlgorithmNamePrefix() {return "";}
165
166 protected:
167 Integer ComputeGroupOrder(const Integer &modulus) const
168 {return modulus-(GetFieldType() == 1 ? 1 : -1);}
169
170 // GF(p) = 1, GF(p^2) = 2
171 virtual int GetFieldType() const =0;
172 virtual unsigned int GetDefaultSubgroupOrderSize(unsigned int modulusSize) const;
173
174 private:
175 Integer m_q;
176 };
177
178 /// \brief Integer-based GroupParameters default implementation
179 /// \tparam GROUP_PRECOMP group parameters precomputation specialization
180 /// \tparam BASE_PRECOMP base class precomputation specialization
181 template <class GROUP_PRECOMP, class BASE_PRECOMP = DL_FixedBasePrecomputationImpl<typename GROUP_PRECOMP::Element> >
182 class CRYPTOPP_NO_VTABLE DL_GroupParameters_IntegerBasedImpl : public DL_GroupParametersImpl<GROUP_PRECOMP, BASE_PRECOMP, DL_GroupParameters_IntegerBased>
183 {
184 typedef DL_GroupParameters_IntegerBasedImpl<GROUP_PRECOMP, BASE_PRECOMP> ThisClass;
185
186 public:
187 typedef typename GROUP_PRECOMP::Element Element;
188
189 virtual ~DL_GroupParameters_IntegerBasedImpl() {}
190
191 // GeneratibleCryptoMaterial interface
192 bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const
193 {return GetValueHelper<DL_GroupParameters_IntegerBased>(this, name, valueType, pValue).Assignable();}
194
195 void AssignFrom(const NameValuePairs &source)
196 {AssignFromHelper<DL_GroupParameters_IntegerBased>(this, source);}
197
198 // DL_GroupParameters
199 const DL_FixedBasePrecomputation<Element> & GetBasePrecomputation() const {return this->m_gpc;}
200 DL_FixedBasePrecomputation<Element> & AccessBasePrecomputation() {return this->m_gpc;}
201
202 // IntegerGroupParameters
203 /// \brief Retrieve the modulus for the group
204 /// \return the modulus for the group
205 const Integer & GetModulus() const {return this->m_groupPrecomputation.GetModulus();}
206
207 /// \brief Retrieves a reference to the group generator
208 /// \return const reference to the group generator
209 const Integer & GetGenerator() const {return this->m_gpc.GetBase(this->GetGroupPrecomputation());}
210
211 void SetModulusAndSubgroupGenerator(const Integer &p, const Integer &g) // these have to be set together
212 {this->m_groupPrecomputation.SetModulus(p); this->m_gpc.SetBase(this->GetGroupPrecomputation(), g); this->ParametersChanged();}
213
214 // non-inherited
215 bool operator==(const DL_GroupParameters_IntegerBasedImpl<GROUP_PRECOMP, BASE_PRECOMP> &rhs) const
216 {return GetModulus() == rhs.GetModulus() && GetGenerator() == rhs.GetGenerator() && this->GetSubgroupOrder() == rhs.GetSubgroupOrder();}
217 bool operator!=(const DL_GroupParameters_IntegerBasedImpl<GROUP_PRECOMP, BASE_PRECOMP> &rhs) const
218 {return !operator==(rhs);}
219 };
220
221 CRYPTOPP_DLL_TEMPLATE_CLASS DL_GroupParameters_IntegerBasedImpl<ModExpPrecomputation>;
222
223 /// \brief GF(p) group parameters
224 class CRYPTOPP_DLL DL_GroupParameters_GFP : public DL_GroupParameters_IntegerBasedImpl<ModExpPrecomputation>
225 {
226 public:
227 virtual ~DL_GroupParameters_GFP() {}
228
229 /// \brief Determines if an element is an identity
230 /// \param element element to check
231 /// \return true if the element is an identity, false otherwise
232 /// \details The identity element or or neutral element is a special element
233 /// in a group that leaves other elements unchanged when combined with it.
234 /// \details IsIdentity() must be implemented in a derived class.
235 bool IsIdentity(const Integer &element) const {return element == Integer::One();}
236
237 /// \brief Exponentiates a base to multiple exponents
238 /// \param results an array of Elements
239 /// \param base the base to raise to the exponents
240 /// \param exponents an array of exponents
241 /// \param exponentsCount the number of exponents in the array
242 /// \details SimultaneousExponentiate() raises the base to each exponent in
243 /// the exponents array and stores the result at the respective position in
244 /// the results array.
245 /// \details SimultaneousExponentiate() must be implemented in a derived class.
246 /// \pre <tt>COUNTOF(results) == exponentsCount</tt>
247 /// \pre <tt>COUNTOF(exponents) == exponentsCount</tt>
248 void SimultaneousExponentiate(Element *results, const Element &base, const Integer *exponents, unsigned int exponentsCount) const;
249
250 /// \brief Get a named value
251 /// \param name the name of the object or value to retrieve
252 /// \param valueType reference to a variable that receives the value
253 /// \param pValue void pointer to a variable that receives the value
254 /// \return true if the value was retrieved, false otherwise
255 /// \details GetVoidValue() retrieves the value of name if it exists.
256 /// \note GetVoidValue() is an internal function and should be implemented
257 /// by derived classes. Users should use one of the other functions instead.
258 /// \sa GetValue(), GetValueWithDefault(), GetIntValue(), GetIntValueWithDefault(),
259 /// GetRequiredParameter() and GetRequiredIntParameter()
260 bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const
261 {
262 return GetValueHelper<DL_GroupParameters_IntegerBased>(this, name, valueType, pValue).Assignable();
263 }
264
265 // used by MQV
266 Element MultiplyElements(const Element &a, const Element &b) const;
267 Element CascadeExponentiate(const Element &element1, const Integer &exponent1, const Element &element2, const Integer &exponent2) const;
268
269 protected:
270 int GetFieldType() const {return 1;}
271 };
272
273 /// \brief GF(p) group parameters that default to safe primes
274 class CRYPTOPP_DLL DL_GroupParameters_GFP_DefaultSafePrime : public DL_GroupParameters_GFP
275 {
276 public:
277 typedef NoCofactorMultiplication DefaultCofactorOption;
278
279 virtual ~DL_GroupParameters_GFP_DefaultSafePrime() {}
280
281 protected:
282 unsigned int GetDefaultSubgroupOrderSize(unsigned int modulusSize) const {return modulusSize-1;}
283 };
284
285 /// ElGamal encryption for safe interop
286 /// \sa <A HREF="https://eprint.iacr.org/2021/923.pdf">On the
287 /// (in)security of ElGamal in OpenPGP</A>,
288 /// <A HREF="https://github.com/weidai11/cryptopp/issues/1059">Issue 1059</A>,
289 /// <A HREF="https://nvd.nist.gov/vuln/detail/CVE-2021-40530">CVE-2021-40530</A>
290 /// \since Crypto++ 8.6
291 class CRYPTOPP_DLL DL_GroupParameters_ElGamal : public DL_GroupParameters_GFP_DefaultSafePrime
292 {
293 public:
294 typedef NoCofactorMultiplication DefaultCofactorOption;
295
296 virtual ~DL_GroupParameters_ElGamal() {}
297
298 Integer GetMaxExponent() const
299 {
300 return GetSubgroupOrder()-1;
301 }
302 };
303
304 /// \brief GDSA algorithm
305 /// \tparam T FieldElement type or class
306 /// \details FieldElement <tt>T</tt> can be Integer, ECP or EC2N.
307 template <class T>
308 class DL_Algorithm_GDSA : public DL_ElgamalLikeSignatureAlgorithm<T>
309 {
310 public:
311 CRYPTOPP_STATIC_CONSTEXPR const char* CRYPTOPP_API StaticAlgorithmName() {return "DSA-1363";}
312
313 virtual ~DL_Algorithm_GDSA() {}
314
315 void Sign(const DL_GroupParameters<T> &params, const Integer &x, const Integer &k, const Integer &e, Integer &r, Integer &s) const
316 {
317 const Integer &q = params.GetSubgroupOrder();
318 r %= q;
319 Integer kInv = k.InverseMod(q);
320 s = (kInv * (x*r + e)) % q;
321 CRYPTOPP_ASSERT(!!r && !!s);
322 }
323
324 bool Verify(const DL_GroupParameters<T> &params, const DL_PublicKey<T> &publicKey, const Integer &e, const Integer &r, const Integer &s) const
325 {
326 const Integer &q = params.GetSubgroupOrder();
327 if (r>=q || r<1 || s>=q || s<1)
328 return false;
329
330 Integer w = s.InverseMod(q);
331 Integer u1 = (e * w) % q;
332 Integer u2 = (r * w) % q;
333 // verify r == (g^u1 * y^u2 mod p) mod q
334 return r == params.ConvertElementToInteger(publicKey.CascadeExponentiateBaseAndPublicElement(u1, u2)) % q;
335 }
336 };
337
338 /// \brief DSA signature algorithm based on RFC 6979
339 /// \tparam T FieldElement type or class
340 /// \tparam H HashTransformation derived class
341 /// \details FieldElement <tt>T</tt> can be Integer, ECP or EC2N.
342 /// \sa <a href="http://tools.ietf.org/rfc/rfc6979.txt">RFC 6979, Deterministic Usage of the
343 /// Digital Signature Algorithm (DSA) and Elliptic Curve Digital Signature Algorithm (ECDSA)</a>
344 /// \since Crypto++ 6.0
345 template <class T, class H>
346 class DL_Algorithm_DSA_RFC6979 : public DL_Algorithm_GDSA<T>, public DeterministicSignatureAlgorithm
347 {
348 public:
349 CRYPTOPP_STATIC_CONSTEXPR const char* CRYPTOPP_API StaticAlgorithmName() {return "DSA-RFC6979";}
350
351 virtual ~DL_Algorithm_DSA_RFC6979() {}
352
353 bool IsProbabilistic() const
354 {return false;}
355 bool IsDeterministic() const
356 {return true;}
357
358 // Deterministic K
359 Integer GenerateRandom(const Integer &x, const Integer &q, const Integer &e) const
360 {
361 static const byte zero = 0, one = 1;
362 const size_t qlen = q.BitCount();
363 const size_t rlen = BitsToBytes(qlen);
364
365 // Step (a) - formatted E(m)
366 SecByteBlock BH(e.MinEncodedSize());
367 e.Encode(BH, BH.size());
368 BH = bits2octets(BH, q);
369
370 // Step (a) - private key to byte array
371 SecByteBlock BX(STDMAX(rlen, x.MinEncodedSize()));
372 x.Encode(BX, BX.size());
373
374 // Step (b)
375 SecByteBlock V(H::DIGESTSIZE);
376 std::fill(V.begin(), V.begin()+H::DIGESTSIZE, one);
377
378 // Step (c)
379 SecByteBlock K(H::DIGESTSIZE);
380 std::fill(K.begin(), K.begin()+H::DIGESTSIZE, zero);
381
382 // Step (d)
383 m_hmac.SetKey(K, K.size());
384 m_hmac.Update(V, V.size());
385 m_hmac.Update(&zero, 1);
386 m_hmac.Update(BX, BX.size());
387 m_hmac.Update(BH, BH.size());
388 m_hmac.TruncatedFinal(K, K.size());
389
390 // Step (e)
391 m_hmac.SetKey(K, K.size());
392 m_hmac.Update(V, V.size());
393 m_hmac.TruncatedFinal(V, V.size());
394
395 // Step (f)
396 m_hmac.SetKey(K, K.size());
397 m_hmac.Update(V, V.size());
398 m_hmac.Update(&one, 1);
399 m_hmac.Update(BX, BX.size());
400 m_hmac.Update(BH, BH.size());
401 m_hmac.TruncatedFinal(K, K.size());
402
403 // Step (g)
404 m_hmac.SetKey(K, K.size());
405 m_hmac.Update(V, V.size());
406 m_hmac.TruncatedFinal(V, V.size());
407
408 Integer k;
409 SecByteBlock temp(rlen);
410 for (;;)
411 {
412 // We want qlen bits, but we support only hash functions with an output length
413 // multiple of 8; hence, we will gather rlen bits, i.e., rolen octets.
414 size_t toff = 0;
415 while (toff < rlen)
416 {
417 m_hmac.Update(V, V.size());
418 m_hmac.TruncatedFinal(V, V.size());
419
420 size_t cc = STDMIN(V.size(), temp.size() - toff);
421 memcpy_s(temp+toff, temp.size() - toff, V, cc);
422 toff += cc;
423 }
424
425 k = bits2int(temp, qlen);
426 if (k > 0 && k < q)
427 break;
428
429 // k is not in the proper range; update K and V, and loop.
430 m_hmac.Update(V, V.size());
431 m_hmac.Update(&zero, 1);
432 m_hmac.TruncatedFinal(K, K.size());
433
434 m_hmac.SetKey(K, K.size());
435 m_hmac.Update(V, V.size());
436 m_hmac.TruncatedFinal(V, V.size());
437 }
438
439 return k;
440 }
441
442 protected:
443
444 Integer bits2int(const SecByteBlock& bits, size_t qlen) const
445 {
446 Integer ret(bits, bits.size());
447 size_t blen = bits.size()*8;
448
449 if (blen > qlen)
450 ret >>= blen - qlen;
451
452 return ret;
453 }
454
455 // RFC 6979 support function. Takes an integer and converts it into bytes that
456 // are the same length as an elliptic curve's order.
457 SecByteBlock int2octets(const Integer& val, size_t rlen) const
458 {
459 SecByteBlock block(val.MinEncodedSize());
460 val.Encode(block, val.MinEncodedSize());
461
462 if (block.size() == rlen)
463 return block;
464
465 // The least significant bytes are the ones we need to preserve.
466 SecByteBlock t(rlen);
467 if (block.size() > rlen)
468 {
469 size_t offset = block.size() - rlen;
470 std::memcpy(t, block + offset, rlen);
471 }
472 else // block.size() < rlen
473 {
474 size_t offset = rlen - block.size();
475 std::memset(t, '\x00', offset);
476 std::memcpy(t + offset, block, rlen - offset);
477 }
478
479 return t;
480 }
481
482 // Turn a stream of bits into a set of bytes with the same length as an elliptic
483 // curve's order.
484 SecByteBlock bits2octets(const SecByteBlock& in, const Integer& q) const
485 {
486 Integer b2 = bits2int(in, q.BitCount());
487 Integer b1 = b2 - q;
488 return int2octets(b1.IsNegative() ? b2 : b1, q.ByteCount());
489 }
490
491 private:
492 mutable H m_hash;
493 mutable HMAC<H> m_hmac;
494 };
495
496 /// \brief German Digital Signature Algorithm
497 /// \tparam T FieldElement type or class
498 /// \details FieldElement <tt>T</tt> can be Integer, ECP or EC2N.
499 /// \details The Digital Signature Scheme ECGDSA does not define the algorithm over integers. Rather, the
500 /// signature algorithm is only defined over elliptic curves. However, the library design is such that the
501 /// generic algorithm reside in <tt>gfpcrypt.h</tt>.
502 /// \sa Erwin Hess, Marcus Schafheutle, and Pascale Serf <A HREF="http://www.teletrust.de/fileadmin/files/oid/ecgdsa_final.pdf">
503 /// The Digital Signature Scheme ECGDSA (October 24, 2006)</A>
504 template <class T>
505 class DL_Algorithm_GDSA_ISO15946 : public DL_ElgamalLikeSignatureAlgorithm<T>
506 {
507 public:
508 CRYPTOPP_STATIC_CONSTEXPR const char* CRYPTOPP_API StaticAlgorithmName() {return "GDSA-ISO15946";}
509
510 virtual ~DL_Algorithm_GDSA_ISO15946() {}
511
512 void Sign(const DL_GroupParameters<T> &params, const Integer &x, const Integer &k, const Integer &e, Integer &r, Integer &s) const
513 {
514 const Integer &q = params.GetSubgroupOrder();
515 // r = x(k * G) mod q
516 r = params.ConvertElementToInteger(params.ExponentiateBase(k)) % q;
517 // s = (k * r - h(m)) * d_A mod q
518 s = (k * r - e) * x % q;
519 CRYPTOPP_ASSERT(!!r && !!s);
520 }
521
522 bool Verify(const DL_GroupParameters<T> &params, const DL_PublicKey<T> &publicKey, const Integer &e, const Integer &r, const Integer &s) const
523 {
524 const Integer &q = params.GetSubgroupOrder();
525 if (r>=q || r<1 || s>=q || s<1)
526 return false;
527
528 const Integer& rInv = r.InverseMod(q);
529 const Integer u1 = (rInv * e) % q;
530 const Integer u2 = (rInv * s) % q;
531 // verify x(G^u1 + P_A^u2) mod q
532 return r == params.ConvertElementToInteger(publicKey.CascadeExponentiateBaseAndPublicElement(u1, u2)) % q;
533 }
534 };
535
536 CRYPTOPP_DLL_TEMPLATE_CLASS DL_Algorithm_GDSA<Integer>;
537 CRYPTOPP_DLL_TEMPLATE_CLASS DL_Algorithm_DSA_RFC6979<Integer, SHA1>;
538 CRYPTOPP_DLL_TEMPLATE_CLASS DL_Algorithm_DSA_RFC6979<Integer, SHA224>;
539 CRYPTOPP_DLL_TEMPLATE_CLASS DL_Algorithm_DSA_RFC6979<Integer, SHA256>;
540 CRYPTOPP_DLL_TEMPLATE_CLASS DL_Algorithm_DSA_RFC6979<Integer, SHA384>;
541 CRYPTOPP_DLL_TEMPLATE_CLASS DL_Algorithm_DSA_RFC6979<Integer, SHA512>;
542
543 /// \brief NR algorithm
544 /// \tparam T FieldElement type or class
545 /// \details FieldElement <tt>T</tt> can be Integer, ECP or EC2N.
546 template <class T>
547 class DL_Algorithm_NR : public DL_ElgamalLikeSignatureAlgorithm<T>
548 {
549 public:
550 CRYPTOPP_STATIC_CONSTEXPR const char* CRYPTOPP_API StaticAlgorithmName() {return "NR";}
551
552 virtual ~DL_Algorithm_NR() {}
553
554 void Sign(const DL_GroupParameters<T> &params, const Integer &x, const Integer &k, const Integer &e, Integer &r, Integer &s) const
555 {
556 const Integer &q = params.GetSubgroupOrder();
557 r = (r + e) % q;
558 s = (k - x*r) % q;
559 CRYPTOPP_ASSERT(!!r);
560 }
561
562 bool Verify(const DL_GroupParameters<T> &params, const DL_PublicKey<T> &publicKey, const Integer &e, const Integer &r, const Integer &s) const
563 {
564 const Integer &q = params.GetSubgroupOrder();
565 if (r>=q || r<1 || s>=q)
566 return false;
567
568 // check r == (m_g^s * m_y^r + m) mod m_q
569 return r == (params.ConvertElementToInteger(publicKey.CascadeExponentiateBaseAndPublicElement(s, r)) + e) % q;
570 }
571 };
572
573 /// \brief Discrete Log (DL) public key in GF(p) groups
574 /// \tparam GP GroupParameters derived class
575 /// \details DSA public key format is defined in 7.3.3 of RFC 2459. The private key format is defined in 12.9 of PKCS #11 v2.10.
576 template <class GP>
577 class DL_PublicKey_GFP : public DL_PublicKeyImpl<GP>
578 {
579 public:
580 virtual ~DL_PublicKey_GFP() {}
581
582 /// \brief Initialize a public key over GF(p)
583 /// \param params the group parameters
584 /// \param y the public element
585 void Initialize(const DL_GroupParameters_IntegerBased &params, const Integer &y)
586 {this->AccessGroupParameters().Initialize(params); this->SetPublicElement(y);}
587
588 /// \brief Initialize a public key over GF(p)
589 /// \param p the modulus
590 /// \param g the generator
591 /// \param y the public element
592 void Initialize(const Integer &p, const Integer &g, const Integer &y)
593 {this->AccessGroupParameters().Initialize(p, g); this->SetPublicElement(y);}
594
595 /// \brief Initialize a public key over GF(p)
596 /// \param p the modulus
597 /// \param q the subgroup order
598 /// \param g the generator
599 /// \param y the public element
600 void Initialize(const Integer &p, const Integer &q, const Integer &g, const Integer &y)
601 {this->AccessGroupParameters().Initialize(p, q, g); this->SetPublicElement(y);}
602
603 // X509PublicKey
604 void BERDecodePublicKey(BufferedTransformation &bt, bool, size_t)
605 {this->SetPublicElement(Integer(bt));}
606 void DEREncodePublicKey(BufferedTransformation &bt) const
607 {this->GetPublicElement().DEREncode(bt);}
608 };
609
610 /// \brief Discrete Log (DL) private key in GF(p) groups
611 /// \tparam GP GroupParameters derived class
612 template <class GP>
613 class DL_PrivateKey_GFP : public DL_PrivateKeyImpl<GP>
614 {
615 public:
616 virtual ~DL_PrivateKey_GFP();
617
618 /// \brief Create a private key
619 /// \param rng a RandomNumberGenerator derived class
620 /// \param modulusBits the size of the modulus, in bits
621 /// \details This function overload of Initialize() creates a new private key because it
622 /// takes a RandomNumberGenerator() as a parameter. If you have an existing keypair,
623 /// then use one of the other Initialize() overloads.
624 void Initialize(RandomNumberGenerator &rng, unsigned int modulusBits)
625 {this->GenerateRandomWithKeySize(rng, modulusBits);}
626
627 /// \brief Create a private key
628 /// \param rng a RandomNumberGenerator derived class
629 /// \param p the modulus
630 /// \param g the generator
631 /// \details This function overload of Initialize() creates a new private key because it
632 /// takes a RandomNumberGenerator() as a parameter. If you have an existing keypair,
633 /// then use one of the other Initialize() overloads.
634 void Initialize(RandomNumberGenerator &rng, const Integer &p, const Integer &g)
635 {this->GenerateRandom(rng, MakeParameters("Modulus", p)("SubgroupGenerator", g));}
636
637 /// \brief Create a private key
638 /// \param rng a RandomNumberGenerator derived class
639 /// \param p the modulus
640 /// \param q the subgroup order
641 /// \param g the generator
642 /// \details This function overload of Initialize() creates a new private key because it
643 /// takes a RandomNumberGenerator() as a parameter. If you have an existing keypair,
644 /// then use one of the other Initialize() overloads.
645 void Initialize(RandomNumberGenerator &rng, const Integer &p, const Integer &q, const Integer &g)
646 {this->GenerateRandom(rng, MakeParameters("Modulus", p)("SubgroupOrder", q)("SubgroupGenerator", g));}
647
648 /// \brief Initialize a private key over GF(p)
649 /// \param params the group parameters
650 /// \param x the private exponent
651 void Initialize(const DL_GroupParameters_IntegerBased &params, const Integer &x)
652 {this->AccessGroupParameters().Initialize(params); this->SetPrivateExponent(x);}
653
654 /// \brief Initialize a private key over GF(p)
655 /// \param p the modulus
656 /// \param g the generator
657 /// \param x the private exponent
658 void Initialize(const Integer &p, const Integer &g, const Integer &x)
659 {this->AccessGroupParameters().Initialize(p, g); this->SetPrivateExponent(x);}
660
661 /// \brief Initialize a private key over GF(p)
662 /// \param p the modulus
663 /// \param q the subgroup order
664 /// \param g the generator
665 /// \param x the private exponent
666 void Initialize(const Integer &p, const Integer &q, const Integer &g, const Integer &x)
667 {this->AccessGroupParameters().Initialize(p, q, g); this->SetPrivateExponent(x);}
668 };
669
670 // Out-of-line dtor due to AIX and GCC, http://github.com/weidai11/cryptopp/issues/499
671 template <class GP>
672 DL_PrivateKey_GFP<GP>::~DL_PrivateKey_GFP() {}
673
674 /// \brief Discrete Log (DL) signing/verification keys in GF(p) groups
675 struct DL_SignatureKeys_GFP
676 {
677 typedef DL_GroupParameters_GFP GroupParameters;
678 typedef DL_PublicKey_GFP<GroupParameters> PublicKey;
679 typedef DL_PrivateKey_GFP<GroupParameters> PrivateKey;
680 };
681
682 /// \brief Discrete Log (DL) encryption/decryption keys in GF(p) groups
683 struct DL_CryptoKeys_GFP
684 {
685 typedef DL_GroupParameters_GFP_DefaultSafePrime GroupParameters;
686 typedef DL_PublicKey_GFP<GroupParameters> PublicKey;
687 typedef DL_PrivateKey_GFP<GroupParameters> PrivateKey;
688 };
689
690 /// ElGamal encryption keys for safe interop
691 /// \sa <A HREF="https://eprint.iacr.org/2021/923.pdf">On the
692 /// (in)security of ElGamal in OpenPGP</A>,
693 /// <A HREF="https://github.com/weidai11/cryptopp/issues/1059">Issue 1059</A>,
694 /// <A HREF="https://nvd.nist.gov/vuln/detail/CVE-2021-40530">CVE-2021-40530</A>
695 /// \since Crypto++ 8.6
696 struct DL_CryptoKeys_ElGamal
697 {
698 typedef DL_GroupParameters_ElGamal GroupParameters;
699 typedef DL_PublicKey_GFP<GroupParameters> PublicKey;
700 typedef DL_PrivateKey_GFP<GroupParameters> PrivateKey;
701 };
702
703 /// \brief DSA signature scheme
704 /// \tparam H HashTransformation derived class
705 /// \sa <a href="http://www.weidai.com/scan-mirror/sig.html#DSA-1363">DSA-1363</a>
706 /// \since Crypto++ 1.0 for DSA, Crypto++ 5.6.2 for DSA2
707 template <class H>
708 struct GDSA : public DL_SS<
709 DL_SignatureKeys_GFP,
710 DL_Algorithm_GDSA<Integer>,
711 DL_SignatureMessageEncodingMethod_DSA,
712 H>
713 {
714 };
715
716 /// \brief NR signature scheme
717 /// \tparam H HashTransformation derived class
718 /// \sa <a href="http://www.weidai.com/scan-mirror/sig.html#NR">NR</a>
719 template <class H>
720 struct NR : public DL_SS<
721 DL_SignatureKeys_GFP,
722 DL_Algorithm_NR<Integer>,
723 DL_SignatureMessageEncodingMethod_NR,
724 H>
725 {
726 };
727
728 /// \brief DSA group parameters
729 /// \details These are GF(p) group parameters that are allowed by the DSA standard
730 /// \sa DL_Keys_DSA
731 /// \since Crypto++ 1.0
732 class CRYPTOPP_DLL DL_GroupParameters_DSA : public DL_GroupParameters_GFP
733 {
734 public:
735 virtual ~DL_GroupParameters_DSA() {}
736
737 /// \brief Check the group for errors
738 /// \param rng RandomNumberGenerator for objects which use randomized testing
739 /// \param level level of thoroughness
740 /// \return true if the tests succeed, false otherwise
741 /// \details ValidateGroup() also checks that the lengths of p and q are allowed
742 /// by the DSA standard.
743 /// \details There are four levels of thoroughness:
744 /// <ul>
745 /// <li>0 - using this object won't cause a crash or exception
746 /// <li>1 - this object will probably function, and encrypt, sign, other operations correctly
747 /// <li>2 - ensure this object will function correctly, and perform reasonable security checks
748 /// <li>3 - perform reasonable security checks, and do checks that may take a long time
749 /// </ul>
750 /// \details Level 0 does not require a RandomNumberGenerator. A NullRNG() can be used for level 0.
751 /// Level 1 may not check for weak keys and such. Levels 2 and 3 are recommended.
752 bool ValidateGroup(RandomNumberGenerator &rng, unsigned int level) const;
753
754 /// \brief Generate a random key or crypto parameters
755 /// \param rng a RandomNumberGenerator to produce keying material
756 /// \param alg additional initialization parameters
757 /// \details NameValuePairs can be ModulusSize alone; or Modulus, SubgroupOrder, and
758 /// SubgroupGenerator. ModulusSize must be between <tt>DSA::MIN_PRIME_LENGTH</tt> and
759 /// <tt>DSA::MAX_PRIME_LENGTH</tt>, and divisible by <tt>DSA::PRIME_LENGTH_MULTIPLE</tt>.
760 /// \details An example of changing the modulus size using NameValuePairs is shown below.
761 /// <pre>
762 /// AlgorithmParameters params = MakeParameters
763 /// (Name::ModulusSize(), 2048);
764 ///
765 /// DL_GroupParameters_DSA groupParams;
766 /// groupParams.GenerateRandom(prng, params);
767 /// </pre>
768 /// \throw KeyingErr if a key can't be generated or algorithm parameters are invalid.
769 void GenerateRandom(RandomNumberGenerator &rng, const NameValuePairs &alg);
770
771 /// \brief Check the prime length for errors
772 /// \param pbits number of bits in the prime number
773 /// \return true if the tests succeed, false otherwise
774 static bool CRYPTOPP_API IsValidPrimeLength(unsigned int pbits)
775 {return pbits >= MIN_PRIME_LENGTH && pbits <= MAX_PRIME_LENGTH && pbits % PRIME_LENGTH_MULTIPLE == 0;}
776
777 /// \brief DSA prime length
778 enum {
779 /// \brief Minimum prime length
780 MIN_PRIME_LENGTH = 1024,
781 /// \brief Maximum prime length
782 MAX_PRIME_LENGTH = 3072,
783 /// \brief Prime length multiple
784 PRIME_LENGTH_MULTIPLE = 1024
785 };
786 };
787
788 template <class H>
789 class DSA2;
790
791 /// \brief DSA keys
792 /// \sa DL_GroupParameters_DSA
793 /// \since Crypto++ 1.0
794 struct DL_Keys_DSA
795 {
796 typedef DL_PublicKey_GFP<DL_GroupParameters_DSA> PublicKey;
797 typedef DL_PrivateKey_WithSignaturePairwiseConsistencyTest<DL_PrivateKey_GFP<DL_GroupParameters_DSA>, DSA2<SHA1> > PrivateKey;
798 };
799
800 /// \brief DSA signature scheme
801 /// \tparam H HashTransformation derived class
802 /// \details The class is named DSA2 instead of DSA for backwards compatibility because
803 /// DSA was a non-template class.
804 /// \details DSA default method GenerateRandom uses a 2048-bit modulus and a 224-bit subgoup by default.
805 /// The modulus can be changed using the following code:
806 /// <pre>
807 /// DSA::PrivateKey privateKey;
808 /// privateKey.GenerateRandomWithKeySize(prng, 2048);
809 /// </pre>
810 /// \details The subgroup order can be changed using the following code:
811 /// <pre>
812 /// AlgorithmParameters params = MakeParameters
813 /// (Name::ModulusSize(), 2048)
814 /// (Name::SubgroupOrderSize(), 256);
815 ///
816 /// DSA::PrivateKey privateKey;
817 /// privateKey.GenerateRandom(prng, params);
818 /// </pre>
819 /// \sa <a href="http://en.wikipedia.org/wiki/Digital_Signature_Algorithm">DSA</a>, as specified in FIPS 186-3,
820 /// <a href="https://www.cryptopp.com/wiki/Digital_Signature_Algorithm">Digital Signature Algorithm</a> on the wiki, and
821 /// <a href="https://www.cryptopp.com/wiki/NameValuePairs">NameValuePairs</a> on the wiki.
822 /// \since Crypto++ 1.0 for DSA, Crypto++ 5.6.2 for DSA2, Crypto++ 6.1 for 2048-bit modulus.
823 template <class H>
824 class DSA2 : public DL_SS<
825 DL_Keys_DSA,
826 DL_Algorithm_GDSA<Integer>,
827 DL_SignatureMessageEncodingMethod_DSA,
828 H,
829 DSA2<H> >
830 {
831 public:
832 static std::string CRYPTOPP_API StaticAlgorithmName() {return "DSA/" + (std::string)H::StaticAlgorithmName();}
833 };
834
835 /// \brief DSA deterministic signature scheme
836 /// \tparam H HashTransformation derived class
837 /// \sa <a href="http://www.weidai.com/scan-mirror/sig.html#DSA-1363">DSA-1363</a>
838 /// \since Crypto++ 1.0 for DSA, Crypto++ 5.6.2 for DSA2
839 template <class H>
840 struct DSA_RFC6979 : public DL_SS<
841 DL_SignatureKeys_GFP,
842 DL_Algorithm_DSA_RFC6979<Integer, H>,
843 DL_SignatureMessageEncodingMethod_DSA,
844 H,
845 DSA_RFC6979<H> >
846 {
847 static std::string CRYPTOPP_API StaticAlgorithmName() {return std::string("DSA-RFC6979/") + H::StaticAlgorithmName();}
848 };
849
850 /// DSA with SHA-1, typedef'd for backwards compatibility
851 typedef DSA2<SHA1> DSA;
852
853 CRYPTOPP_DLL_TEMPLATE_CLASS DL_PublicKey_GFP<DL_GroupParameters_DSA>;
854 CRYPTOPP_DLL_TEMPLATE_CLASS DL_PrivateKey_GFP<DL_GroupParameters_DSA>;
855 CRYPTOPP_DLL_TEMPLATE_CLASS DL_PrivateKey_WithSignaturePairwiseConsistencyTest<DL_PrivateKey_GFP<DL_GroupParameters_DSA>, DSA2<SHA1> >;
856
857 /// \brief P1363 based XOR Encryption Method
858 /// \tparam MAC MessageAuthenticationCode derived class used for MAC computation
859 /// \tparam DHAES_MODE flag indicating DHAES mode
860 /// \tparam LABEL_OCTETS flag indicating the label is octet count
861 /// \details DL_EncryptionAlgorithm_Xor is based on an early P1363 draft, which itself appears to be based on an
862 /// early Certicom SEC-1 draft (or an early SEC-1 draft was based on a P1363 draft). Crypto++ 4.2 used it in its Integrated
863 /// Ecryption Schemes with <tt>NoCofactorMultiplication</tt>, <tt>DHAES_MODE=false</tt> and <tt>LABEL_OCTETS=true</tt>.
864 /// \details If you need this method for Crypto++ 4.2 compatibility, then use the ECIES template class with
865 /// <tt>NoCofactorMultiplication</tt>, <tt>DHAES_MODE=false</tt> and <tt>LABEL_OCTETS=true</tt>.
866 /// \details If you need this method for Bouncy Castle 1.54 and Botan 1.11 compatibility, then use the ECIES template class with
867 /// <tt>NoCofactorMultiplication</tt>, <tt>DHAES_MODE=true</tt> and <tt>LABEL_OCTETS=false</tt>.
868 /// \details Bouncy Castle 1.54 and Botan 1.11 compatibility are the default template parameters.
869 /// \since Crypto++ 4.0
870 template <class MAC, bool DHAES_MODE, bool LABEL_OCTETS=false>
871 class DL_EncryptionAlgorithm_Xor : public DL_SymmetricEncryptionAlgorithm
872 {
873 public:
874 virtual ~DL_EncryptionAlgorithm_Xor() {}
875
876 bool ParameterSupported(const char *name) const {return strcmp(name, Name::EncodingParameters()) == 0;}
877 size_t GetSymmetricKeyLength(size_t plaintextLength) const
878 {return plaintextLength + static_cast<size_t>(MAC::DEFAULT_KEYLENGTH);}
879 size_t GetSymmetricCiphertextLength(size_t plaintextLength) const
880 {return plaintextLength + static_cast<size_t>(MAC::DIGESTSIZE);}
881 size_t GetMaxSymmetricPlaintextLength(size_t ciphertextLength) const
882 {return SaturatingSubtract(ciphertextLength, static_cast<size_t>(MAC::DIGESTSIZE));}
883 void SymmetricEncrypt(RandomNumberGenerator &rng, const byte *key, const byte *plaintext, size_t plaintextLength, byte *ciphertext, const NameValuePairs &parameters) const
884 {
885 CRYPTOPP_UNUSED(rng);
886 const byte *cipherKey = NULLPTR, *macKey = NULLPTR;
887 if (DHAES_MODE)
888 {
889 macKey = key;
890 cipherKey = key + MAC::DEFAULT_KEYLENGTH;
891 }
892 else
893 {
894 cipherKey = key;
895 macKey = key + plaintextLength;
896 }
897
898 ConstByteArrayParameter encodingParameters;
899 parameters.GetValue(Name::EncodingParameters(), encodingParameters);
900
901 if (plaintextLength) // Coverity finding
902 xorbuf(ciphertext, plaintext, cipherKey, plaintextLength);
903
904 MAC mac(macKey);
905 mac.Update(ciphertext, plaintextLength);
906 mac.Update(encodingParameters.begin(), encodingParameters.size());
907 if (DHAES_MODE)
908 {
909 byte L[8];
910 PutWord(false, BIG_ENDIAN_ORDER, L, (LABEL_OCTETS ? word64(encodingParameters.size()) : 8 * word64(encodingParameters.size())));
911 mac.Update(L, 8);
912 }
913 mac.Final(ciphertext + plaintextLength);
914 }
915 DecodingResult SymmetricDecrypt(const byte *key, const byte *ciphertext, size_t ciphertextLength, byte *plaintext, const NameValuePairs &parameters) const
916 {
917 size_t plaintextLength = GetMaxSymmetricPlaintextLength(ciphertextLength);
918 const byte *cipherKey, *macKey;
919 if (DHAES_MODE)
920 {
921 macKey = key;
922 cipherKey = key + MAC::DEFAULT_KEYLENGTH;
923 }
924 else
925 {
926 cipherKey = key;
927 macKey = key + plaintextLength;
928 }
929
930 ConstByteArrayParameter encodingParameters;
931 parameters.GetValue(Name::EncodingParameters(), encodingParameters);
932
933 MAC mac(macKey);
934 mac.Update(ciphertext, plaintextLength);
935 mac.Update(encodingParameters.begin(), encodingParameters.size());
936 if (DHAES_MODE)
937 {
938 byte L[8];
939 PutWord(false, BIG_ENDIAN_ORDER, L, (LABEL_OCTETS ? word64(encodingParameters.size()) : 8 * word64(encodingParameters.size())));
940 mac.Update(L, 8);
941 }
942 if (!mac.Verify(ciphertext + plaintextLength))
943 return DecodingResult();
944
945 if (plaintextLength) // Coverity finding
946 xorbuf(plaintext, ciphertext, cipherKey, plaintextLength);
947
948 return DecodingResult(plaintextLength);
949 }
950 };
951
952 /// \brief P1363 based Key Derivation Method
953 /// \tparam T FieldElement type or class
954 /// \tparam DHAES_MODE flag indicating DHAES mode
955 /// \tparam KDF key derivation function
956 /// \details FieldElement <tt>T</tt> can be Integer, ECP or EC2N.
957 template <class T, bool DHAES_MODE, class KDF>
958 class DL_KeyDerivationAlgorithm_P1363 : public DL_KeyDerivationAlgorithm<T>
959 {
960 public:
961 virtual ~DL_KeyDerivationAlgorithm_P1363() {}
962
963 bool ParameterSupported(const char *name) const {return strcmp(name, Name::KeyDerivationParameters()) == 0;}
964 void Derive(const DL_GroupParameters<T> &params, byte *derivedKey, size_t derivedLength, const T &agreedElement, const T &ephemeralPublicKey, const NameValuePairs &parameters) const
965 {
966 SecByteBlock agreedSecret;
967 if (DHAES_MODE)
968 {
969 agreedSecret.New(params.GetEncodedElementSize(true) + params.GetEncodedElementSize(false));
970 params.EncodeElement(true, ephemeralPublicKey, agreedSecret);
971 params.EncodeElement(false, agreedElement, agreedSecret + params.GetEncodedElementSize(true));
972 }
973 else
974 {
975 agreedSecret.New(params.GetEncodedElementSize(false));
976 params.EncodeElement(false, agreedElement, agreedSecret);
977 }
978
979 ConstByteArrayParameter derivationParameters;
980 parameters.GetValue(Name::KeyDerivationParameters(), derivationParameters);
981 KDF::DeriveKey(derivedKey, derivedLength, agreedSecret, agreedSecret.size(), derivationParameters.begin(), derivationParameters.size());
982 }
983 };
984
985 /// \brief Discrete Log Integrated Encryption Scheme
986 /// \tparam COFACTOR_OPTION cofactor multiplication option
987 /// \tparam HASH HashTransformation derived class used for key drivation and MAC computation
988 /// \tparam DHAES_MODE flag indicating if the MAC includes addition context parameters such as the label
989 /// \tparam LABEL_OCTETS flag indicating if the label size is specified in octets or bits
990 /// \details DLIES is an Integer based Integrated Encryption Scheme (IES). The scheme combines a Key Encapsulation Method (KEM)
991 /// with a Data Encapsulation Method (DEM) and a MAC tag. The scheme is
992 /// <A HREF="http://en.wikipedia.org/wiki/ciphertext_indistinguishability">IND-CCA2</A>, which is a strong notion of security.
993 /// You should prefer an Integrated Encryption Scheme over homegrown schemes.
994 /// \details The library's original implementation is based on an early P1363 draft, which itself appears to be based on an early Certicom
995 /// SEC-1 draft (or an early SEC-1 draft was based on a P1363 draft). Crypto++ 4.2 used the early draft in its Integrated Ecryption
996 /// Schemes with <tt>NoCofactorMultiplication</tt>, <tt>DHAES_MODE=false</tt> and <tt>LABEL_OCTETS=true</tt>.
997 /// \details If you desire an Integrated Encryption Scheme with Crypto++ 4.2 compatibility, then use the DLIES template class with
998 /// <tt>NoCofactorMultiplication</tt>, <tt>DHAES_MODE=false</tt> and <tt>LABEL_OCTETS=true</tt>.
999 /// \details If you desire an Integrated Encryption Scheme with Bouncy Castle 1.54 and Botan 1.11 compatibility, then use the DLIES
1000 /// template class with <tt>NoCofactorMultiplication</tt>, <tt>DHAES_MODE=true</tt> and <tt>LABEL_OCTETS=false</tt>.
1001 /// \details The default template parameters ensure compatibility with Bouncy Castle 1.54 and Botan 1.11. The combination of
1002 /// <tt>IncompatibleCofactorMultiplication</tt> and <tt>DHAES_MODE=true</tt> is recommended for best efficiency and security.
1003 /// SHA1 is used for compatibility reasons, but it can be changed if desired. SHA-256 or another hash will likely improve the
1004 /// security provided by the MAC. The hash is also used in the key derivation function as a PRF.
1005 /// \details Below is an example of constructing a Crypto++ 4.2 compatible DLIES encryptor and decryptor.
1006 /// <pre>
1007 /// AutoSeededRandomPool prng;
1008 /// DL_PrivateKey_GFP<DL_GroupParameters_GFP> key;
1009 /// key.Initialize(prng, 2048);
1010 ///
1011 /// DLIES<SHA1,NoCofactorMultiplication,true,true>::Decryptor decryptor(key);
1012 /// DLIES<SHA1,NoCofactorMultiplication,true,true>::Encryptor encryptor(decryptor);
1013 /// </pre>
1014 /// \sa ECIES, <a href="http://www.weidai.com/scan-mirror/ca.html#DLIES">Discrete Log Integrated Encryption Scheme (DLIES)</a>,
1015 /// Martínez, Encinas, and Ávila's <A HREF="http://digital.csic.es/bitstream/10261/32671/1/V2-I2-P7-13.pdf">A Survey of the Elliptic
1016 /// Curve Integrated Encryption Schemes</A>
1017 /// \since Crypto++ 4.0, Crypto++ 5.7 for Bouncy Castle and Botan compatibility
1018 template <class HASH = SHA1, class COFACTOR_OPTION = NoCofactorMultiplication, bool DHAES_MODE = true, bool LABEL_OCTETS=false>
1019 struct DLIES
1020 : public DL_ES<
1021 DL_CryptoKeys_GFP,
1022 DL_KeyAgreementAlgorithm_DH<Integer, COFACTOR_OPTION>,
1023 DL_KeyDerivationAlgorithm_P1363<Integer, DHAES_MODE, P1363_KDF2<HASH> >,
1024 DL_EncryptionAlgorithm_Xor<HMAC<HASH>, DHAES_MODE, LABEL_OCTETS>,
1025 DLIES<> >
1026 {
1027 static std::string CRYPTOPP_API StaticAlgorithmName() {return "DLIES";} // TODO: fix this after name is standardized
1028 };
1029
1030 NAMESPACE_END
1031
1032 #if CRYPTOPP_MSC_VERSION
1033 # pragma warning(pop)
1034 #endif
1035
1036 #endif
algparam.h
Classes for working with NameValuePairs.
MakeParameters
AlgorithmParameters MakeParameters(const char *name, const T &value, bool throwIfNotUsed=true)
Create an object that implements NameValuePairs.
Definition: algparam.h:508
asn.h
Classes and functions for working with ANS.1 objects.
operator==
bool operator==(const OID &lhs, const OID &rhs)
Compare two OIDs for equality.
operator!=
bool operator!=(const OID &lhs, const OID &rhs)
Compare two OIDs for inequality.
ASN1CryptoMaterial
Encode and decode ASN.1 objects with additional information.
Definition: asn.h:685
BufferedTransformation
Interface for buffered transformations.
Definition: cryptlib.h:1657
ConstByteArrayParameter
Used to pass byte array input as part of a NameValuePairs object.
Definition: algparam.h:25
ConstByteArrayParameter::size
size_t size() const
Length of the memory block.
Definition: algparam.h:88
ConstByteArrayParameter::begin
const byte * begin() const
Pointer to the first byte in the memory block.
Definition: algparam.h:84
DL_Algorithm_DSA_RFC6979
DSA signature algorithm based on RFC 6979.
Definition: gfpcrypt.h:347
DL_Algorithm_DSA_RFC6979::GenerateRandom
Integer GenerateRandom(const Integer &x, const Integer &q, const Integer &e) const
Generate k.
Definition: gfpcrypt.h:359
DL_Algorithm_DSA_RFC6979::IsDeterministic
bool IsDeterministic() const
Signature scheme flag.
Definition: gfpcrypt.h:355
DL_Algorithm_GDSA_ISO15946
German Digital Signature Algorithm.
Definition: gfpcrypt.h:506
DL_Algorithm_GDSA_ISO15946::Sign
void Sign(const DL_GroupParameters< T > &params, const Integer &x, const Integer &k, const Integer &e, Integer &r, Integer &s) const
Sign a message using a private key.
Definition: gfpcrypt.h:512
DL_Algorithm_GDSA_ISO15946::Verify
bool Verify(const DL_GroupParameters< T > &params, const DL_PublicKey< T > &publicKey, const Integer &e, const Integer &r, const Integer &s) const
Verify a message using a public key.
Definition: gfpcrypt.h:522
DL_Algorithm_GDSA
GDSA algorithm.
Definition: gfpcrypt.h:309
DL_Algorithm_GDSA::Verify
bool Verify(const DL_GroupParameters< T > &params, const DL_PublicKey< T > &publicKey, const Integer &e, const Integer &r, const Integer &s) const
Verify a message using a public key.
Definition: gfpcrypt.h:324
DL_Algorithm_GDSA::Sign
void Sign(const DL_GroupParameters< T > &params, const Integer &x, const Integer &k, const Integer &e, Integer &r, Integer &s) const
Sign a message using a private key.
Definition: gfpcrypt.h:315
DL_Algorithm_NR
NR algorithm.
Definition: gfpcrypt.h:548
DL_Algorithm_NR::Verify
bool Verify(const DL_GroupParameters< T > &params, const DL_PublicKey< T > &publicKey, const Integer &e, const Integer &r, const Integer &s) const
Verify a message using a public key.
Definition: gfpcrypt.h:562
DL_Algorithm_NR::Sign
void Sign(const DL_GroupParameters< T > &params, const Integer &x, const Integer &k, const Integer &e, Integer &r, Integer &s) const
Sign a message using a private key.
Definition: gfpcrypt.h:554
DL_ES
Discrete Log (DL) encryption scheme.
Definition: pubkey.h:2362
DL_ElgamalLikeSignatureAlgorithm
Interface for Elgamal-like signature algorithms.
Definition: pubkey.h:1407
DL_EncryptionAlgorithm_Xor
P1363 based XOR Encryption Method.
Definition: gfpcrypt.h:872
DL_FixedBasePrecomputation< Integer >
DL_GroupParameters_DSA
DSA group parameters.
Definition: gfpcrypt.h:733
DL_GroupParameters_DSA::ValidateGroup
bool ValidateGroup(RandomNumberGenerator &rng, unsigned int level) const
Check the group for errors.
DL_GroupParameters_DSA::GenerateRandom
void GenerateRandom(RandomNumberGenerator &rng, const NameValuePairs &alg)
Generate a random key or crypto parameters.
DL_GroupParameters_DSA::IsValidPrimeLength
static bool IsValidPrimeLength(unsigned int pbits)
Check the prime length for errors.
Definition: gfpcrypt.h:774
DL_GroupParameters_ElGamal
ElGamal encryption for safe interop.
Definition: gfpcrypt.h:292
DL_GroupParameters_ElGamal::GetMaxExponent
Integer GetMaxExponent() const
Retrieves the maximum exponent for the group.
Definition: gfpcrypt.h:298
DL_GroupParameters_GFP_DefaultSafePrime
GF(p) group parameters that default to safe primes.
Definition: gfpcrypt.h:275
DL_GroupParameters_GFP
GF(p) group parameters.
Definition: gfpcrypt.h:225
DL_GroupParameters_GFP::SimultaneousExponentiate
void SimultaneousExponentiate(Element *results, const Element &base, const Integer *exponents, unsigned int exponentsCount) const
Exponentiates a base to multiple exponents.
DL_GroupParameters_GFP::GetVoidValue
bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const
Get a named value.
Definition: gfpcrypt.h:260
DL_GroupParameters_GFP::IsIdentity
bool IsIdentity(const Integer &element) const
Determines if an element is an identity.
Definition: gfpcrypt.h:235
DL_GroupParameters_IntegerBased
Integer-based GroupParameters specialization.
Definition: gfpcrypt.h:35
DL_GroupParameters_IntegerBased::AssignFrom
void AssignFrom(const NameValuePairs &source)
Initialize or reinitialize this key.
DL_GroupParameters_IntegerBased::Initialize
void Initialize(const Integer &p, const Integer &g)
Initialize a group parameters over integers.
Definition: gfpcrypt.h:58
DL_GroupParameters_IntegerBased::GetGroupOrder
Integer GetGroupOrder() const
Retrieves the order of the group.
Definition: gfpcrypt.h:99
DL_GroupParameters_IntegerBased::SetModulusAndSubgroupGenerator
virtual void SetModulusAndSubgroupGenerator(const Integer &p, const Integer &g)=0
Set group parameters.
DL_GroupParameters_IntegerBased::Initialize
void Initialize(RandomNumberGenerator &rng, unsigned int pbits)
Create a group parameters over integers.
Definition: gfpcrypt.h:52
DL_GroupParameters_IntegerBased::GetAlgorithmID
OID GetAlgorithmID() const
Retrieve the OID of the algorithm.
DL_GroupParameters_IntegerBased::DEREncode
void DEREncode(BufferedTransformation &bt) const
Encode this object into a BufferedTransformation.
DL_GroupParameters_IntegerBased::GetModulus
virtual const Integer & GetModulus() const =0
Retrieve the modulus for the group.
DL_GroupParameters_IntegerBased::GetMaxExponent
Integer GetMaxExponent() const
Retrieve the maximum exponent for the group.
DL_GroupParameters_IntegerBased::SetSubgroupOrder
void SetSubgroupOrder(const Integer &q)
Set subgroup order.
Definition: gfpcrypt.h:161
DL_GroupParameters_IntegerBased::DecodeElement
Integer DecodeElement(const byte *encoded, bool checkForGroupMembership) const
Decodes the element.
DL_GroupParameters_IntegerBased::ConvertElementToInteger
Integer ConvertElementToInteger(const Element &element) const
Converts an element to an Integer.
Definition: gfpcrypt.h:139
DL_GroupParameters_IntegerBased::GenerateRandom
void GenerateRandom(RandomNumberGenerator &rng, const NameValuePairs &alg)
Generate a random key.
DL_GroupParameters_IntegerBased::BERDecode
void BERDecode(BufferedTransformation &bt)
Decode this object from a BufferedTransformation.
DL_GroupParameters_IntegerBased::ValidateGroup
bool ValidateGroup(RandomNumberGenerator &rng, unsigned int level) const
Check the group for errors.
DL_GroupParameters_IntegerBased::Initialize
void Initialize(const DL_GroupParameters_IntegerBased &params)
Initialize a group parameters over integers.
Definition: gfpcrypt.h:43
DL_GroupParameters_IntegerBased::FastSubgroupCheckAvailable
bool FastSubgroupCheckAvailable() const
Determine if subgroup membership check is fast.
Definition: gfpcrypt.h:105
DL_GroupParameters_IntegerBased::GetEncodedElementSize
unsigned int GetEncodedElementSize(bool reversible) const
Retrieve the encoded element's size.
DL_GroupParameters_IntegerBased::Initialize
void Initialize(const Integer &p, const Integer &q, const Integer &g)
Initialize a group parameters over integers.
Definition: gfpcrypt.h:65
DL_GroupParameters_IntegerBased::GetVoidValue
bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const
Get a named value.
DL_GroupParameters_IntegerBased::GetSubgroupOrder
const Integer & GetSubgroupOrder() const
Retrieves the subgroup order.
Definition: gfpcrypt.h:98
DL_GroupParameters_IntegerBased::EncodeElement
void EncodeElement(bool reversible, const Element &element, byte *encoded) const
Encodes the element.
DL_GroupParameters_IntegerBasedImpl
Integer-based GroupParameters default implementation.
Definition: gfpcrypt.h:183
DL_GroupParameters_IntegerBasedImpl::AssignFrom
void AssignFrom(const NameValuePairs &source)
Initialize or reinitialize this key.
Definition: gfpcrypt.h:195
DL_GroupParameters_IntegerBasedImpl::GetGenerator
const Integer & GetGenerator() const
Retrieves a reference to the group generator.
Definition: gfpcrypt.h:209
DL_GroupParameters_IntegerBasedImpl::GetModulus
const Integer & GetModulus() const
Retrieve the modulus for the group.
Definition: gfpcrypt.h:205
DL_GroupParameters_IntegerBasedImpl::GetBasePrecomputation
const DL_FixedBasePrecomputation< Element > & GetBasePrecomputation() const
Retrieves the group precomputation.
Definition: gfpcrypt.h:199
DL_GroupParameters_IntegerBasedImpl::SetModulusAndSubgroupGenerator
void SetModulusAndSubgroupGenerator(const Integer &p, const Integer &g)
Set group parameters.
Definition: gfpcrypt.h:211
DL_GroupParameters_IntegerBasedImpl::GetVoidValue
bool GetVoidValue(const char *name, const std::type_info &valueType, void *pValue) const
Get a named value.
Definition: gfpcrypt.h:192
DL_GroupParameters_IntegerBasedImpl::AccessBasePrecomputation
DL_FixedBasePrecomputation< Element > & AccessBasePrecomputation()
Retrieves the group precomputation.
Definition: gfpcrypt.h:200
DL_GroupParameters
Interface for Discrete Log (DL) group parameters.
Definition: pubkey.h:782
DL_GroupParameters::EncodeElement
virtual void EncodeElement(bool reversible, const Element &element, byte *encoded) const =0
Encodes the element.
DL_GroupParameters::GetSubgroupGenerator
virtual const Element & GetSubgroupGenerator() const
Retrieves the subgroup generator.
Definition: pubkey.h:859
DL_GroupParameters::GetEncodedElementSize
virtual unsigned int GetEncodedElementSize(bool reversible) const =0
Retrieves the encoded element's size.
DL_GroupParameters::ExponentiateBase
virtual Element ExponentiateBase(const Integer &exponent) const
Exponentiates the base.
Definition: pubkey.h:869
DL_GroupParameters< typename GROUP_PRECOMP::Element >::GetSubgroupOrder
virtual const Integer & GetSubgroupOrder() const=0
Retrieves the subgroup order.
DL_GroupParameters::ConvertElementToInteger
virtual Integer ConvertElementToInteger(const Element &element) const =0
Converts an element to an Integer.
DL_GroupParametersImpl
Base implementation of Discrete Log (DL) group parameters.
Definition: pubkey.h:1014
DL_GroupParametersImpl::GetGroupPrecomputation
const DL_GroupPrecomputation< Element > & GetGroupPrecomputation() const
Retrieves the group precomputation.
Definition: pubkey.h:1024
DL_KeyDerivationAlgorithm_P1363
P1363 based Key Derivation Method.
Definition: gfpcrypt.h:959
DL_KeyDerivationAlgorithm
Interface for key derivation algorithms used in DL cryptosystems.
Definition: pubkey.h:1493
DL_PrivateKey_GFP
Discrete Log (DL) private key in GF(p) groups.
Definition: gfpcrypt.h:614
DL_PrivateKey_GFP::Initialize
void Initialize(RandomNumberGenerator &rng, const Integer &p, const Integer &q, const Integer &g)
Create a private key.
Definition: gfpcrypt.h:645
DL_PrivateKey_GFP::Initialize
void Initialize(RandomNumberGenerator &rng, const Integer &p, const Integer &g)
Create a private key.
Definition: gfpcrypt.h:634
DL_PrivateKey_GFP::Initialize
void Initialize(RandomNumberGenerator &rng, unsigned int modulusBits)
Create a private key.
Definition: gfpcrypt.h:624
DL_PrivateKey_GFP::Initialize
void Initialize(const Integer &p, const Integer &q, const Integer &g, const Integer &x)
Initialize a private key over GF(p)
Definition: gfpcrypt.h:666
DL_PrivateKey_GFP::Initialize
void Initialize(const Integer &p, const Integer &g, const Integer &x)
Initialize a private key over GF(p)
Definition: gfpcrypt.h:658
DL_PrivateKey_GFP::Initialize
void Initialize(const DL_GroupParameters_IntegerBased &params, const Integer &x)
Initialize a private key over GF(p)
Definition: gfpcrypt.h:651
DL_PrivateKey_WithSignaturePairwiseConsistencyTest
Definition: pubkey.h:1315
DL_PrivateKeyImpl
Discrete Log (DL) private key base implementation.
Definition: pubkey.h:1239
DL_PrivateKeyImpl::GenerateRandom
void GenerateRandom(RandomNumberGenerator &rng, const NameValuePairs &params)
Generate a random key or crypto parameters.
Definition: pubkey.h:1276
DL_PrivateKeyImpl::SetPrivateExponent
void SetPrivateExponent(const Integer &x)
Sets the private exponent.
Definition: pubkey.h:1301
DL_PublicKey_GFP
Discrete Log (DL) public key in GF(p) groups.
Definition: gfpcrypt.h:578
DL_PublicKey_GFP::Initialize
void Initialize(const DL_GroupParameters_IntegerBased &params, const Integer &y)
Initialize a public key over GF(p)
Definition: gfpcrypt.h:585
DL_PublicKey_GFP::Initialize
void Initialize(const Integer &p, const Integer &g, const Integer &y)
Initialize a public key over GF(p)
Definition: gfpcrypt.h:592
DL_PublicKey_GFP::DEREncodePublicKey
void DEREncodePublicKey(BufferedTransformation &bt) const
Encode subjectPublicKey part of subjectPublicKeyInfo.
Definition: gfpcrypt.h:606
DL_PublicKey_GFP::BERDecodePublicKey
void BERDecodePublicKey(BufferedTransformation &bt, bool, size_t)
Decode subjectPublicKey part of subjectPublicKeyInfo.
Definition: gfpcrypt.h:604
DL_PublicKey_GFP::Initialize
void Initialize(const Integer &p, const Integer &q, const Integer &g, const Integer &y)
Initialize a public key over GF(p)
Definition: gfpcrypt.h:600
DL_PublicKey
Interface for Discrete Log (DL) public keys.
Definition: pubkey.h:1059
DL_PublicKey< GP::Element >::SetPublicElement
virtual void SetPublicElement(const Element &y)
Sets the public element.
Definition: pubkey.h:1093
DL_PublicKey< GP::Element >::GetPublicElement
virtual const Element & GetPublicElement() const
Retrieves the public element.
Definition: pubkey.h:1089
DL_PublicKey::CascadeExponentiateBaseAndPublicElement
virtual Element CascadeExponentiateBaseAndPublicElement(const Integer &baseExp, const Integer &publicExp) const
Exponentiates an element.
Definition: pubkey.h:1110
DL_PublicKeyImpl
Discrete Log (DL) public key base implementation.
Definition: pubkey.h:1336
DL_SS
Discrete Log (DL) signature scheme.
Definition: pubkey.h:2342
DL_SymmetricEncryptionAlgorithm
Interface for symmetric encryption algorithms used in DL cryptosystems.
Definition: pubkey.h:1505
DSA2
DSA signature scheme.
Definition: gfpcrypt.h:830
DeterministicSignatureAlgorithm
Interface for deterministic signers.
Definition: pubkey.h:1460
GeneratableCryptoMaterial::GenerateRandomWithKeySize
void GenerateRandomWithKeySize(RandomNumberGenerator &rng, unsigned int keySize)
Generate a random key or crypto parameters.
HMAC< H >
Integer
Multiple precision integer with arithmetic operations.
Definition: integer.h:50
Integer::MinEncodedSize
size_t MinEncodedSize(Signedness sign=UNSIGNED) const
Minimum number of bytes to encode this integer.
Integer::One
static const Integer & One()
Integer representing 1.
Integer::BitCount
unsigned int BitCount() const
Determines the number of bits required to represent the Integer.
Integer::IsNegative
bool IsNegative() const
Determines if the Integer is negative.
Definition: integer.h:341
Integer::ByteCount
unsigned int ByteCount() const
Determines the number of bytes required to represent the Integer.
Integer::Encode
void Encode(byte *output, size_t outputLen, Signedness sign=UNSIGNED) const
Encode in big-endian format.
Integer::InverseMod
Integer InverseMod(const Integer &n) const
Calculate multiplicative inverse.
NameValuePairs
Interface for retrieving values given their names.
Definition: cryptlib.h:327
NameValuePairs::GetValue
bool GetValue(const char *name, T &value) const
Get a named value.
Definition: cryptlib.h:384
OID
Object Identifier.
Definition: asn.h:265
RandomNumberGenerator
Interface for random number generators.
Definition: cryptlib.h:1440
SecBlock::begin
iterator begin()
Provides an iterator pointing to the first element in the memory block.
Definition: secblock.h:836
SecBlock::New
void New(size_type newSize)
Change size without preserving contents.
Definition: secblock.h:1126
SecBlock::size
size_type size() const
Provides the count of elements in the SecBlock.
Definition: secblock.h:867
SecByteBlock
SecBlock<byte> typedef.
Definition: secblock.h:1226
config.h
Library configuration file.
CRYPTOPP_API
#define CRYPTOPP_API
Win32 calling convention.
Definition: config_dll.h:119
CRYPTOPP_DLL_TEMPLATE_CLASS
#define CRYPTOPP_DLL_TEMPLATE_CLASS
Instantiate templates in a dynamic library.
Definition: config_dll.h:72
word64
unsigned long long word64
64-bit unsigned datatype
Definition: config_int.h:101
cryptlib.h
Abstract base classes that provide a uniform interface to this library.
BIG_ENDIAN_ORDER
@ BIG_ENDIAN_ORDER
byte order is big-endian
Definition: cryptlib.h:152
DSA
DSA2< SHA1 > DSA
DSA with SHA-1, typedef'd for backwards compatibility.
Definition: gfpcrypt.h:851
hmac.h
Classes for HMAC message authentication codes.
integer.h
Multiple precision integer with arithmetic operations.
misc.h
Utility functions for the Crypto++ library.
SaturatingSubtract
T1 SaturatingSubtract(const T1 &a, const T2 &b)
Performs a saturating subtract clamped at 0.
Definition: misc.h:1302
memcpy_s
void memcpy_s(void *dest, size_t sizeInBytes, const void *src, size_t count)
Bounds checking replacement for memcpy()
Definition: misc.h:527
BitsToBytes
size_t BitsToBytes(size_t bitCount)
Returns the number of 8-bit bytes or octets required for the specified number of bits.
Definition: misc.h:1143
STDMIN
const T & STDMIN(const T &a, const T &b)
Replacement function for std::min.
Definition: misc.h:657
PutWord
void PutWord(bool assumeAligned, ByteOrder order, byte *block, T value, const byte *xorBlock=NULL)
Access a block of memory.
Definition: misc.h:2948
STDMAX
const T & STDMAX(const T &a, const T &b)
Replacement function for std::max.
Definition: misc.h:668
xorbuf
CRYPTOPP_DLL void xorbuf(byte *buf, const byte *mask, size_t count)
Performs an XOR of a buffer with a mask.
CryptoPP
Crypto++ library namespace.
Name::KeyDerivationParameters
const char * KeyDerivationParameters()
ConstByteArrayParameter.
Definition: argnames.h:67
Name::EncodingParameters
const char * EncodingParameters()
ConstByteArrayParameter.
Definition: argnames.h:66
pubkey.h
This file contains helper classes/functions for implementing public key algorithms.
sha.h
Classes for SHA-1 and SHA-2 family of message digests.
smartptr.h
Classes for automatic resource management.
DL_CryptoKeys_ElGamal
ElGamal encryption keys for safe interop.
Definition: gfpcrypt.h:697
DL_CryptoKeys_GFP
Discrete Log (DL) encryption/decryption keys in GF(p) groups.
Definition: gfpcrypt.h:684
DL_Keys_DSA
DSA keys.
Definition: gfpcrypt.h:795
DL_SignatureKeys_GFP
Discrete Log (DL) signing/verification keys in GF(p) groups.
Definition: gfpcrypt.h:676
DLIES
Discrete Log Integrated Encryption Scheme.
Definition: gfpcrypt.h:1026
DSA_RFC6979
DSA deterministic signature scheme.
Definition: gfpcrypt.h:846
DecodingResult
Returns a decoding results.
Definition: cryptlib.h:283
EnumToType
Converts an enumeration to a type suitable for use as a template parameter.
Definition: cryptlib.h:141
GDSA
DSA signature scheme.
Definition: gfpcrypt.h:713
NR
NR signature scheme.
Definition: gfpcrypt.h:725
CRYPTOPP_ASSERT
#define CRYPTOPP_ASSERT(exp)
Debugging and diagnostic assertion.
Definition: trap.h:68