Botan: src/engine/gnump/gmp_wrap.cpp Source File

Botan 1.10.17

gmp_wrap.cpp
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1 /*
2 * GMP Wrapper
3 * (C) 1999-2007 Jack Lloyd
4 *
5 * Distributed under the terms of the Botan license
6 */
7
8 #include <botan/internal/gmp_wrap.h>
9
10 #define GNU_MP_VERSION_CODE_FOR(a,b,c) ((a << 16) | (b << 8) | (c))
11
12 #define GNU_MP_VERSION_CODE \
13 GNU_MP_VERSION_CODE_FOR(__GNU_MP_VERSION, __GNU_MP_VERSION_MINOR, \
14 __GNU_MP_VERSION_PATCHLEVEL)
15
16 #if GNU_MP_VERSION_CODE < GNU_MP_VERSION_CODE_FOR(4,1,0)
17 #error Your GNU MP install is too old, upgrade to 4.1 or later
18 #endif
19
20 namespace Botan {
21
22 /*
23 * GMP_MPZ Constructor
24 */
25 GMP_MPZ::GMP_MPZ(const BigInt& in)
26 {
27 mpz_init(value);
28 if(in != 0)
29 mpz_import(value, in.sig_words(), -1, sizeof(word), 0, 0, in.data());
30 }
31
32 /*
33 * GMP_MPZ Constructor
34 */
35 GMP_MPZ::GMP_MPZ(const byte in[], size_t length)
36 {
37 mpz_init(value);
38 mpz_import(value, length, 1, 1, 0, 0, in);
39 }
40
41 /*
42 * GMP_MPZ Copy Constructor
43 */
44 GMP_MPZ::GMP_MPZ(const GMP_MPZ& other)
45 {
46 mpz_init_set(value, other.value);
47 }
48
49 /*
50 * GMP_MPZ Destructor
51 */
52 GMP_MPZ::~GMP_MPZ()
53 {
54 mpz_clear(value);
55 }
56
57 /*
58 * GMP_MPZ Assignment Operator
59 */
60 GMP_MPZ& GMP_MPZ::operator=(const GMP_MPZ& other)
61 {
62 mpz_set(value, other.value);
63 return (*this);
64 }
65
66 /*
67 * Export the mpz_t as a bytestring
68 */
69 void GMP_MPZ::encode(byte out[], size_t length) const
70 {
71 size_t dummy = 0;
72 mpz_export(out + (length - bytes()), &dummy, 1, 1, 0, 0, value);
73 }
74
75 /*
76 * Return the number of significant bytes
77 */
78 size_t GMP_MPZ::bytes() const
79 {
80 return ((mpz_sizeinbase(value, 2) + 7) / 8);
81 }
82
83 /*
84 * GMP to BigInt Conversions
85 */
86 BigInt GMP_MPZ::to_bigint() const
87 {
88 BigInt out(BigInt::Positive, (bytes() + sizeof(word) - 1) / sizeof(word));
89 size_t dummy = 0;
90 mpz_export(out.get_reg(), &dummy, -1, sizeof(word), 0, 0, value);
91
92 if(mpz_sgn(value) < 0)
93 out.flip_sign();
94
95 return out;
96 }
97
98 }
Botan::BigInt
Definition: bigint.h:22
Botan::BigInt::Positive
Definition: bigint.h:33
Botan::BigInt::get_reg
SecureVector< word > & get_reg()
Definition: bigint.h:325
Botan::BigInt::data
const word * data() const
Definition: bigint.h:317
Botan::byte
unsigned char byte
Definition: types.h:22
Botan::GMP_MPZ::to_bigint
BigInt to_bigint() const
Definition: gmp_wrap.cpp:86
Botan::GMP_MPZ::GMP_MPZ
GMP_MPZ(const GMP_MPZ &)
Definition: gmp_wrap.cpp:44
Botan::GMP_MPZ
Definition: gmp_wrap.h:19
Botan::GMP_MPZ::~GMP_MPZ
~GMP_MPZ()
Definition: gmp_wrap.cpp:52
Botan
Definition: algo_base.h:14
Botan::BigInt::sig_words
size_t sig_words() const
Definition: bigint.h:290
Botan::GMP_MPZ::value
mpz_t value
Definition: gmp_wrap.h:22
Botan::GMP_MPZ::operator=
GMP_MPZ & operator=(const GMP_MPZ &)
Definition: gmp_wrap.cpp:60
Botan::GMP_MPZ::encode
void encode(byte[], size_t) const
Definition: gmp_wrap.cpp:69
Botan::BigInt::flip_sign
void flip_sign()
Definition: bigint.cpp:303
Botan::GMP_MPZ::bytes
size_t bytes() const
Definition: gmp_wrap.cpp:78