1BN_BLINDING_new(3)                  OpenSSL                 BN_BLINDING_new(3)
2
3
4

NAME

6       BN_BLINDING_new, BN_BLINDING_free, BN_BLINDING_update,
7       BN_BLINDING_convert, BN_BLINDING_invert, BN_BLINDING_convert_ex,
8       BN_BLINDING_invert_ex, BN_BLINDING_get_thread_id,
9       BN_BLINDING_set_thread_id, BN_BLINDING_thread_id,
10       BN_BLINDING_get_flags, BN_BLINDING_set_flags, BN_BLINDING_create_param
11       - blinding related BIGNUM functions.
12

SYNOPSIS

14        #include <openssl/bn.h>
15
16        BN_BLINDING *BN_BLINDING_new(const BIGNUM *A, const BIGNUM *Ai,
17               BIGNUM *mod);
18        void BN_BLINDING_free(BN_BLINDING *b);
19        int BN_BLINDING_update(BN_BLINDING *b,BN_CTX *ctx);
20        int BN_BLINDING_convert(BIGNUM *n, BN_BLINDING *b, BN_CTX *ctx);
21        int BN_BLINDING_invert(BIGNUM *n, BN_BLINDING *b, BN_CTX *ctx);
22        int BN_BLINDING_convert_ex(BIGNUM *n, BIGNUM *r, BN_BLINDING *b,
23               BN_CTX *ctx);
24        int BN_BLINDING_invert_ex(BIGNUM *n, const BIGNUM *r, BN_BLINDING *b,
25               BN_CTX *ctx);
26        #ifndef OPENSSL_NO_DEPRECATED
27        unsigned long BN_BLINDING_get_thread_id(const BN_BLINDING *);
28        void BN_BLINDING_set_thread_id(BN_BLINDING *, unsigned long);
29        #endif
30        CRYPTO_THREADID *BN_BLINDING_thread_id(BN_BLINDING *);
31        unsigned long BN_BLINDING_get_flags(const BN_BLINDING *);
32        void BN_BLINDING_set_flags(BN_BLINDING *, unsigned long);
33        BN_BLINDING *BN_BLINDING_create_param(BN_BLINDING *b,
34               const BIGNUM *e, BIGNUM *m, BN_CTX *ctx,
35               int (*bn_mod_exp)(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
36                                 const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx),
37               BN_MONT_CTX *m_ctx);
38

DESCRIPTION

40       BN_BLINDING_new() allocates a new BN_BLINDING structure and copies the
41       A and Ai values into the newly created BN_BLINDING object.
42
43       BN_BLINDING_free() frees the BN_BLINDING structure.
44
45       BN_BLINDING_update() updates the BN_BLINDING parameters by squaring the
46       A and Ai or, after specific number of uses and if the necessary
47       parameters are set, by re-creating the blinding parameters.
48
49       BN_BLINDING_convert_ex() multiplies n with the blinding factor A.  If r
50       is not NULL a copy the inverse blinding factor Ai will be returned in r
51       (this is useful if a RSA object is shared among several threads).
52       BN_BLINDING_invert_ex() multiplies n with the inverse blinding factor
53       Ai. If r is not NULL it will be used as the inverse blinding.
54
55       BN_BLINDING_convert() and BN_BLINDING_invert() are wrapper functions
56       for BN_BLINDING_convert_ex() and BN_BLINDING_invert_ex() with r set to
57       NULL.
58
59       BN_BLINDING_thread_id() provides access to the CRYPTO_THREADID object
60       within the BN_BLINDING structure. This is to help users provide proper
61       locking if needed for multi-threaded use. The "thread id" object of a
62       newly allocated BN_BLINDING structure is initialised to the thread id
63       in which BN_BLINDING_new() was called.
64
65       BN_BLINDING_get_flags() returns the BN_BLINDING flags. Currently there
66       are two supported flags: BN_BLINDING_NO_UPDATE and
67       BN_BLINDING_NO_RECREATE. BN_BLINDING_NO_UPDATE inhibits the automatic
68       update of the BN_BLINDING parameters after each use and
69       BN_BLINDING_NO_RECREATE inhibits the automatic re-creation of the
70       BN_BLINDING parameters after a fixed number of uses (currently 32). In
71       newly allocated BN_BLINDING objects no flags are set.
72       BN_BLINDING_set_flags() sets the BN_BLINDING parameters flags.
73
74       BN_BLINDING_create_param() creates new BN_BLINDING parameters using the
75       exponent e and the modulus m. bn_mod_exp and m_ctx can be used to pass
76       special functions for exponentiation (normally BN_mod_exp_mont() and
77       BN_MONT_CTX).
78

RETURN VALUES

80       BN_BLINDING_new() returns the newly allocated BN_BLINDING structure or
81       NULL in case of an error.
82
83       BN_BLINDING_update(), BN_BLINDING_convert(), BN_BLINDING_invert(),
84       BN_BLINDING_convert_ex() and BN_BLINDING_invert_ex() return 1 on
85       success and 0 if an error occurred.
86
87       BN_BLINDING_thread_id() returns a pointer to the thread id object
88       within a BN_BLINDING object.
89
90       BN_BLINDING_get_flags() returns the currently set BN_BLINDING flags (a
91       unsigned long value).
92
93       BN_BLINDING_create_param() returns the newly created BN_BLINDING
94       parameters or NULL on error.
95

SEE ALSO

97       bn(3)
98

HISTORY

100       BN_BLINDING_thread_id was first introduced in OpenSSL 1.0.0, and it
101       deprecates BN_BLINDING_set_thread_id and BN_BLINDING_get_thread_id.
102
103       BN_BLINDING_convert_ex, BN_BLINDIND_invert_ex,
104       BN_BLINDING_get_thread_id, BN_BLINDING_set_thread_id,
105       BN_BLINDING_set_flags, BN_BLINDING_get_flags and
106       BN_BLINDING_create_param were first introduced in OpenSSL 0.9.8
107

AUTHOR

109       Nils Larsch for the OpenSSL project (http://www.openssl.org).
110
111
112
1131.0.2o                            2019-09-10                BN_BLINDING_new(3)
Impressum