1*2175Sjp161948=pod 2*2175Sjp161948 3*2175Sjp161948=head1 NAME 4*2175Sjp161948 5*2175Sjp161948BN_BLINDING_new, BN_BLINDING_free, BN_BLINDING_update, BN_BLINDING_convert, 6*2175Sjp161948BN_BLINDING_invert, BN_BLINDING_convert_ex, BN_BLINDING_invert_ex, 7*2175Sjp161948BN_BLINDING_get_thread_id, BN_BLINDING_set_thread_id, BN_BLINDING_get_flags, 8*2175Sjp161948BN_BLINDING_set_flags, BN_BLINDING_create_param - blinding related BIGNUM 9*2175Sjp161948functions. 10*2175Sjp161948 11*2175Sjp161948=head1 SYNOPSIS 12*2175Sjp161948 13*2175Sjp161948 #include <openssl/bn.h> 14*2175Sjp161948 15*2175Sjp161948 BN_BLINDING *BN_BLINDING_new(const BIGNUM *A, const BIGNUM *Ai, 16*2175Sjp161948 BIGNUM *mod); 17*2175Sjp161948 void BN_BLINDING_free(BN_BLINDING *b); 18*2175Sjp161948 int BN_BLINDING_update(BN_BLINDING *b,BN_CTX *ctx); 19*2175Sjp161948 int BN_BLINDING_convert(BIGNUM *n, BN_BLINDING *b, BN_CTX *ctx); 20*2175Sjp161948 int BN_BLINDING_invert(BIGNUM *n, BN_BLINDING *b, BN_CTX *ctx); 21*2175Sjp161948 int BN_BLINDING_convert_ex(BIGNUM *n, BIGNUM *r, BN_BLINDING *b, 22*2175Sjp161948 BN_CTX *ctx); 23*2175Sjp161948 int BN_BLINDING_invert_ex(BIGNUM *n, const BIGNUM *r, BN_BLINDING *b, 24*2175Sjp161948 BN_CTX *ctx); 25*2175Sjp161948 unsigned long BN_BLINDING_get_thread_id(const BN_BLINDING *); 26*2175Sjp161948 void BN_BLINDING_set_thread_id(BN_BLINDING *, unsigned long); 27*2175Sjp161948 unsigned long BN_BLINDING_get_flags(const BN_BLINDING *); 28*2175Sjp161948 void BN_BLINDING_set_flags(BN_BLINDING *, unsigned long); 29*2175Sjp161948 BN_BLINDING *BN_BLINDING_create_param(BN_BLINDING *b, 30*2175Sjp161948 const BIGNUM *e, BIGNUM *m, BN_CTX *ctx, 31*2175Sjp161948 int (*bn_mod_exp)(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, 32*2175Sjp161948 const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx), 33*2175Sjp161948 BN_MONT_CTX *m_ctx); 34*2175Sjp161948 35*2175Sjp161948=head1 DESCRIPTION 36*2175Sjp161948 37*2175Sjp161948BN_BLINDING_new() allocates a new B<BN_BLINDING> structure and copies 38*2175Sjp161948the B<A> and B<Ai> values into the newly created B<BN_BLINDING> object. 39*2175Sjp161948 40*2175Sjp161948BN_BLINDING_free() frees the B<BN_BLINDING> structure. 41*2175Sjp161948 42*2175Sjp161948BN_BLINDING_update() updates the B<BN_BLINDING> parameters by squaring 43*2175Sjp161948the B<A> and B<Ai> or, after specific number of uses and if the 44*2175Sjp161948necessary parameters are set, by re-creating the blinding parameters. 45*2175Sjp161948 46*2175Sjp161948BN_BLINDING_convert_ex() multiplies B<n> with the blinding factor B<A>. 47*2175Sjp161948If B<r> is not NULL a copy the inverse blinding factor B<Ai> will be 48*2175Sjp161948returned in B<r> (this is useful if a B<RSA> object is shared amoung 49*2175Sjp161948several threads). BN_BLINDING_invert_ex() multiplies B<n> with the 50*2175Sjp161948inverse blinding factor B<Ai>. If B<r> is not NULL it will be used as 51*2175Sjp161948the inverse blinding. 52*2175Sjp161948 53*2175Sjp161948BN_BLINDING_convert() and BN_BLINDING_invert() are wrapper 54*2175Sjp161948functions for BN_BLINDING_convert_ex() and BN_BLINDING_invert_ex() 55*2175Sjp161948with B<r> set to NULL. 56*2175Sjp161948 57*2175Sjp161948BN_BLINDING_set_thread_id() and BN_BLINDING_get_thread_id() 58*2175Sjp161948set and get the "thread id" value of the B<BN_BLINDING> structure, 59*2175Sjp161948a field provided to users of B<BN_BLINDING> structure to help them 60*2175Sjp161948provide proper locking if needed for multi-threaded use. The 61*2175Sjp161948"thread id" of a newly allocated B<BN_BLINDING> structure is zero. 62*2175Sjp161948 63*2175Sjp161948BN_BLINDING_get_flags() returns the BN_BLINDING flags. Currently 64*2175Sjp161948there are two supported flags: B<BN_BLINDING_NO_UPDATE> and 65*2175Sjp161948B<BN_BLINDING_NO_RECREATE>. B<BN_BLINDING_NO_UPDATE> inhibits the 66*2175Sjp161948automatic update of the B<BN_BLINDING> parameters after each use 67*2175Sjp161948and B<BN_BLINDING_NO_RECREATE> inhibits the automatic re-creation 68*2175Sjp161948of the B<BN_BLINDING> parameters after a fixed number of uses (currently 69*2175Sjp16194832). In newly allocated B<BN_BLINDING> objects no flags are set. 70*2175Sjp161948BN_BLINDING_set_flags() sets the B<BN_BLINDING> parameters flags. 71*2175Sjp161948 72*2175Sjp161948BN_BLINDING_create_param() creates new B<BN_BLINDING> parameters 73*2175Sjp161948using the exponent B<e> and the modulus B<m>. B<bn_mod_exp> and 74*2175Sjp161948B<m_ctx> can be used to pass special functions for exponentiation 75*2175Sjp161948(normally BN_mod_exp_mont() and B<BN_MONT_CTX>). 76*2175Sjp161948 77*2175Sjp161948=head1 RETURN VALUES 78*2175Sjp161948 79*2175Sjp161948BN_BLINDING_new() returns the newly allocated B<BN_BLINDING> structure 80*2175Sjp161948or NULL in case of an error. 81*2175Sjp161948 82*2175Sjp161948BN_BLINDING_update(), BN_BLINDING_convert(), BN_BLINDING_invert(), 83*2175Sjp161948BN_BLINDING_convert_ex() and BN_BLINDING_invert_ex() return 1 on 84*2175Sjp161948success and 0 if an error occured. 85*2175Sjp161948 86*2175Sjp161948BN_BLINDING_get_thread_id() returns the thread id (a B<unsigned long> 87*2175Sjp161948value) or 0 if not set. 88*2175Sjp161948 89*2175Sjp161948BN_BLINDING_get_flags() returns the currently set B<BN_BLINDING> flags 90*2175Sjp161948(a B<unsigned long> value). 91*2175Sjp161948 92*2175Sjp161948BN_BLINDING_create_param() returns the newly created B<BN_BLINDING> 93*2175Sjp161948parameters or NULL on error. 94*2175Sjp161948 95*2175Sjp161948=head1 SEE ALSO 96*2175Sjp161948 97*2175Sjp161948L<bn(3)|bn(3)> 98*2175Sjp161948 99*2175Sjp161948=head1 HISTORY 100*2175Sjp161948 101*2175Sjp161948BN_BLINDING_convert_ex, BN_BLINDIND_invert_ex, BN_BLINDING_get_thread_id, 102*2175Sjp161948BN_BLINDING_set_thread_id, BN_BLINDING_set_flags, BN_BLINDING_get_flags 103*2175Sjp161948and BN_BLINDING_create_param were first introduced in OpenSSL 0.9.8 104*2175Sjp161948 105*2175Sjp161948=head1 AUTHOR 106*2175Sjp161948 107*2175Sjp161948Nils Larsch for the OpenSSL project (http://www.openssl.org). 108*2175Sjp161948 109*2175Sjp161948=cut 110