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

donna.h
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1 // donna.h - written and placed in public domain by Jeffrey Walton
2 // Crypto++ specific implementation wrapped around Andrew
3 // Moon's public domain curve25519-donna and ed25519-donna,
4 // https://github.com/floodyberry/curve25519-donna and
5 // https://github.com/floodyberry/ed25519-donna.
6
7 // The curve25519 and ed25519 source files multiplex different repos and
8 // architectures using namespaces. The repos are Andrew Moon's
9 // curve25519-donna and ed25519-donna. The architectures are 32-bit, 64-bit
10 // and SSE. For example, 32-bit x25519 uses symbols from Donna::X25519 and
11 // Donna::Arch32.
12
13 // If needed, see Moon's commit "Go back to ignoring 256th bit [sic]",
14 // https://github.com/floodyberry/curve25519-donna/commit/57a683d18721a658
15
16 /// \file donna.h
17 /// \details Functions for curve25519 and ed25519 operations
18 /// \details This header provides the entry points into Andrew Moon's
19 /// curve25519 and ed25519 curve functions. The Crypto++ classes x25519
20 /// and ed25519 use the functions. The functions are in the <tt>Donna</tt>
21 /// namespace and are curve25519_mult(), ed25519_publickey(),
22 /// ed25519_sign() and ed25519_sign_open().
23 /// \details At the moment the hash function for signing is fixed at
24 /// SHA512.
25
26 #ifndef CRYPTOPP_DONNA_H
27 #define CRYPTOPP_DONNA_H
28
29 #include "config.h"
30 #include "cryptlib.h"
31 #include "stdcpp.h"
32
33 NAMESPACE_BEGIN(CryptoPP)
34 NAMESPACE_BEGIN(Donna)
35
36 //***************************** curve25519 *****************************//
37
38 /// \brief Generate a public key
39 /// \param publicKey byte array for the public key
40 /// \param secretKey byte array with the private key
41 /// \return 0 on success, non-0 otherwise
42 /// \details curve25519_mult() generates a public key from an existing
43 /// secret key. Internally curve25519_mult() performs a scalar
44 /// multiplication using the base point and writes the result to
45 /// <tt>pubkey</tt>.
46 int curve25519_mult(byte publicKey[32], const byte secretKey[32]);
47
48 /// \brief Generate a shared key
49 /// \param sharedKey byte array for the shared secret
50 /// \param secretKey byte array with the private key
51 /// \param othersKey byte array with the peer's public key
52 /// \return 0 on success, non-0 otherwise
53 /// \details curve25519_mult() generates a shared key from an existing
54 /// secret key and the other party's public key. Internally
55 /// curve25519_mult() performs a scalar multiplication using the two keys
56 /// and writes the result to <tt>sharedKey</tt>.
57 int curve25519_mult(byte sharedKey[32], const byte secretKey[32], const byte othersKey[32]);
58
59 //******************************* ed25519 *******************************//
60
61 /// \brief Creates a public key from a secret key
62 /// \param publicKey byte array for the public key
63 /// \param secretKey byte array with the private key
64 /// \return 0 on success, non-0 otherwise
65 /// \details ed25519_publickey() generates a public key from a secret key.
66 /// Internally ed25519_publickey() performs a scalar multiplication
67 /// using the secret key and then writes the result to <tt>publicKey</tt>.
68 int ed25519_publickey(byte publicKey[32], const byte secretKey[32]);
69
70 /// \brief Creates a signature on a message
71 /// \param message byte array with the message
72 /// \param messageLength size of the message, in bytes
73 /// \param publicKey byte array with the public key
74 /// \param secretKey byte array with the private key
75 /// \param signature byte array for the signature
76 /// \return 0 on success, non-0 otherwise
77 /// \details ed25519_sign() generates a signature on a message using
78 /// the public and private keys. The various buffers can be exact
79 /// sizes, and do not require extra space like when using the
80 /// NaCl library functions.
81 /// \details At the moment the hash function for signing is fixed at
82 /// SHA512.
83 int ed25519_sign(const byte* message, size_t messageLength, const byte secretKey[32], const byte publicKey[32], byte signature[64]);
84
85 /// \brief Creates a signature on a message
86 /// \param stream std::istream derived class
87 /// \param publicKey byte array with the public key
88 /// \param secretKey byte array with the private key
89 /// \param signature byte array for the signature
90 /// \return 0 on success, non-0 otherwise
91 /// \details ed25519_sign() generates a signature on a message using
92 /// the public and private keys. The various buffers can be exact
93 /// sizes, and do not require extra space like when using the
94 /// NaCl library functions.
95 /// \details This ed25519_sign() overload handles large streams. It
96 /// was added for signing and verifying files that are too large
97 /// for a memory allocation.
98 /// \details At the moment the hash function for signing is fixed at
99 /// SHA512.
100 int ed25519_sign(std::istream& stream, const byte secretKey[32], const byte publicKey[32], byte signature[64]);
101
102 /// \brief Verifies a signature on a message
103 /// \param message byte array with the message
104 /// \param messageLength size of the message, in bytes
105 /// \param publicKey byte array with the public key
106 /// \param signature byte array with the signature
107 /// \return 0 on success, non-0 otherwise
108 /// \details ed25519_sign_open() verifies a signature on a message using
109 /// the public key. The various buffers can be exact sizes, and do not
110 /// require extra space like when using the NaCl library functions.
111 /// \details At the moment the hash function for signing is fixed at
112 /// SHA512.
113 int
114 ed25519_sign_open(const byte *message, size_t messageLength, const byte publicKey[32], const byte signature[64]);
115
116 /// \brief Verifies a signature on a message
117 /// \param stream std::istream derived class
118 /// \param publicKey byte array with the public key
119 /// \param signature byte array with the signature
120 /// \return 0 on success, non-0 otherwise
121 /// \details ed25519_sign_open() verifies a signature on a message using
122 /// the public key. The various buffers can be exact sizes, and do not
123 /// require extra space like when using the NaCl library functions.
124 /// \details This ed25519_sign_open() overload handles large streams. It
125 /// was added for signing and verifying files that are too large
126 /// for a memory allocation.
127 /// \details At the moment the hash function for signing is fixed at
128 /// SHA512.
129 int
130 ed25519_sign_open(std::istream& stream, const byte publicKey[32], const byte signature[64]);
131
132 //****************************** Internal ******************************//
133
134 #ifndef CRYPTOPP_DOXYGEN_PROCESSING
135
136 // CRYPTOPP_WORD128_AVAILABLE mostly depends upon GCC support for
137 // __SIZEOF_INT128__. If __SIZEOF_INT128__ is not available then Moon
138 // provides routines for MSC and GCC. It should cover most platforms,
139 // but there are gaps like MS ARM64 and XLC. We tried to enable the
140 // 64-bit path for SunCC from 12.5 but we got the dreaded compile
141 // error "The operand ___LCM cannot be assigned to".
142
143 #if defined(CRYPTOPP_WORD128_AVAILABLE) || \
144 (defined(CRYPTOPP_MSC_VERSION) && defined(_M_X64))
145 # define CRYPTOPP_CURVE25519_64BIT 1
146 #else
147 # define CRYPTOPP_CURVE25519_32BIT 1
148 #endif
149
150 // Benchmarking on a modern 64-bit Core i5-6400 @2.7 GHz shows SSE2 on Linux
151 // is not profitable. Here are the numbers in milliseconds/operation:
152 //
153 // * Langley, C++, 0.050
154 // * Moon, C++: 0.040
155 // * Moon, SSE2: 0.061
156 // * Moon, native: 0.045
157 //
158 // However, a modern 64-bit Core i5-3200 @2.5 GHz shows SSE2 is profitable
159 // for MS compilers. Here are the numbers in milliseconds/operation:
160 //
161 // * x86, no SSE2, 0.294
162 // * x86, SSE2, 0.097
163 // * x64, no SSE2, 0.081
164 // * x64, SSE2, 0.071
165
166 #if defined(CRYPTOPP_MSC_VERSION) && (CRYPTOPP_SSE2_INTRIN_AVAILABLE)
167 # define CRYPTOPP_CURVE25519_SSE2 1
168 #endif
169
170 #if (CRYPTOPP_CURVE25519_SSE2)
171 extern int curve25519_mult_SSE2(byte sharedKey[32], const byte secretKey[32], const byte othersKey[32]);
172 #endif
173
174 #endif // CRYPTOPP_DOXYGEN_PROCESSING
175
176 NAMESPACE_END // Donna
177 NAMESPACE_END // CryptoPP
178
179 #endif // CRYPTOPP_DONNA_H
config.h
Library configuration file.
cryptlib.h
Abstract base classes that provide a uniform interface to this library.
ed25519_sign_open
int ed25519_sign_open(const byte *message, size_t messageLength, const byte publicKey[32], const byte signature[64])
Verifies a signature on a message.
ed25519_sign
int ed25519_sign(const byte *message, size_t messageLength, const byte secretKey[32], const byte publicKey[32], byte signature[64])
Creates a signature on a message.
ed25519_publickey
int ed25519_publickey(byte publicKey[32], const byte secretKey[32])
Creates a public key from a secret key.
curve25519_mult
int curve25519_mult(byte publicKey[32], const byte secretKey[32])
Generate a public key.
CryptoPP
Crypto++ library namespace.
stdcpp.h
Common C++ header files.