add docu for BN_BLINDING functions

doc/crypto/BN_BLINDING_new.pod

@@ -0,0 +1,109 @@
+=pod
+
+=head1 NAME
+
+BN_BLINDING_new, BN_BLINDING_free, BN_BLINDING_update, BN_BLINDING_convert, 
+BN_BLINDING_invert, BN_BLINDING_convert_ex, BN_BLINDING_invert_ex, 
+BN_BLINDING_get_thread_id, BN_BLINDING_set_thread_id, BN_BLINDING_get_flags,
+BN_BLINDING_set_flags, BN_BLINDING_create_param - blinding related BIGNUM
+functions.
+
+=head1 SYNOPSIS
+
+ #include <openssl/bn.h>
+
+ BN_BLINDING *BN_BLINDING_new(const BIGNUM *A, const BIGNUM *Ai,
+	BIGNUM *mod);
+ void BN_BLINDING_free(BN_BLINDING *b);
+ int BN_BLINDING_update(BN_BLINDING *b,BN_CTX *ctx);
+ int BN_BLINDING_convert(BIGNUM *n, BN_BLINDING *b, BN_CTX *ctx);
+ int BN_BLINDING_invert(BIGNUM *n, BN_BLINDING *b, BN_CTX *ctx);
+ int BN_BLINDING_convert_ex(BIGNUM *n, BIGNUM *r, BN_BLINDING *b,
+	BN_CTX *ctx);
+ int BN_BLINDING_invert_ex(BIGNUM *n, const BIGNUM *r, BN_BLINDING *b,
+	BN_CTX *ctx);
+ unsigned long BN_BLINDING_get_thread_id(const BN_BLINDING *);
+ void BN_BLINDING_set_thread_id(BN_BLINDING *, unsigned long);
+ unsigned long BN_BLINDING_get_flags(const BN_BLINDING *);
+ void BN_BLINDING_set_flags(BN_BLINDING *, unsigned long);
+ BN_BLINDING *BN_BLINDING_create_param(BN_BLINDING *b,
+	const BIGNUM *e, BIGNUM *m, BN_CTX *ctx,
+	int (*bn_mod_exp)(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
+			  const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx),
+	BN_MONT_CTX *m_ctx);
+
+=head1 DESCRIPTION
+
+BN_BLINDING_new() allocates a new B<BN_BLINDING> structure and copies
+the B<A> and B<Ai> values into the newly created B<BN_BLINDING> object.
+
+BN_BLINDING_free() frees the B<BN_BLINDING> structure.
+
+BN_BLINDING_update() updates the B<BN_BLINDING> parameters by squaring
+the B<A> and B<Ai> or, after specific number of uses and if the
+necessary parameters are set, by re-creating the blinding parameters.
+
+BN_BLINDING_convert_ex() multiplies B<n> with the blinding factor B<A>.
+If B<r> is not NULL a copy the inverse blinding factor B<Ai> will be
+returned in B<r> (this is useful if a B<RSA> object is shared amoung
+several threads). BN_BLINDING_invert_ex() multiplies B<n> with the
+inverse blinding factor B<Ai>. If B<r> is not NULL it will be used as
+the inverse blinding.
+
+BN_BLINDING_convert() and BN_BLINDING_invert() are wrapper
+functions for BN_BLINDING_convert_ex() and BN_BLINDING_invert_ex()
+with B<r> set to NULL.
+
+BN_BLINDING_set_thread_id() and BN_BLINDING_get_thread_id()
+set and get the "thread id" value of the B<BN_BLINDING> structure,
+a field provided to users of B<BN_BLINDING> structure to help them
+provide proper locking if needed for multi-threaded use. The 
+"thread id" of a newly allocated B<BN_BLINDING> structure is zero.
+
+BN_BLINDING_get_flags() returns the BN_BLINDING flags. Currently
+there are two supported flags: B<BN_BLINDING_NO_UPDATE> and
+B<BN_BLINDING_NO_RECREATE>. B<BN_BLINDING_NO_UPDATE> inhibits the
+automatic update of the B<BN_BLINDING> parameters after each use
+and B<BN_BLINDING_NO_RECREATE> inhibits the automatic re-creation
+of the B<BN_BLINDING> parameters after a fixed number of uses (currently
+32). In newly allocated B<BN_BLINDING> objects no flags are set.
+BN_BLINDING_set_flags() sets the B<BN_BLINDING> parameters flags.
+
+BN_BLINDING_create_param() creates new B<BN_BLINDING> parameters
+using the exponent B<e> and the modulus B<m>. B<bn_mod_exp> and
+B<m_ctx> can be used to pass special functions for exponentiation
+(normally BN_mod_exp_mont() and B<BN_MONT_CTX>).
+
+=head1 RETURN VALUES
+
+BN_BLINDING_new() returns the newly allocated B<BN_BLINDING> structure
+or NULL in case of an error.
+
+BN_BLINDING_update(), BN_BLINDING_convert(), BN_BLINDING_invert(),
+BN_BLINDING_convert_ex() and BN_BLINDING_invert_ex() return 1 on
+success and 0 if an error occured.
+
+BN_BLINDING_get_thread_id() returns the thread id (a B<unsigned long>
+value) or 0 if not set.
+
+BN_BLINDING_get_flags() returns the currently set B<BN_BLINDING> flags
+(a B<unsigned long> value).
+
+BN_BLINDING_create_param() returns the newly created B<BN_BLINDING> 
+parameters or NULL on error.
+
+=head1 SEE ALSO
+
+L<bn(3)|bn(3)>
+
+=head1 HISTORY
+
+BN_BLINDING_convert_ex, BN_BLINDIND_invert_ex, BN_BLINDING_get_thread_id,
+BN_BLINDING_set_thread_id, BN_BLINDING_set_flags, BN_BLINDING_get_flags
+and BN_BLINDING_create_param were first introduced in OpenSSL 0.9.8
+
+=head1 AUTHOR
+
+Nils Larsch for the OpenSSL project (http://www.openssl.org).
+
+=cut

doc/crypto/bn.pod

@@ -121,6 +121,25 @@ bn - multiprecision integer arithmetics
  int BN_to_montgomery(BIGNUM *r, BIGNUM *a, BN_MONT_CTX *mont,
          BN_CTX *ctx);
 
+ BN_BLINDING *BN_BLINDING_new(const BIGNUM *A, const BIGNUM *Ai,
+	BIGNUM *mod);
+ void BN_BLINDING_free(BN_BLINDING *b);
+ int BN_BLINDING_update(BN_BLINDING *b,BN_CTX *ctx);
+ int BN_BLINDING_convert(BIGNUM *n, BN_BLINDING *b, BN_CTX *ctx);
+ int BN_BLINDING_invert(BIGNUM *n, BN_BLINDING *b, BN_CTX *ctx);
+ int BN_BLINDING_convert_ex(BIGNUM *n, BIGNUM *r, BN_BLINDING *b,
+	BN_CTX *ctx);
+ int BN_BLINDING_invert_ex(BIGNUM *n,const BIGNUM *r,BN_BLINDING *b,
+	BN_CTX *ctx);
+ unsigned long BN_BLINDING_get_thread_id(const BN_BLINDING *);
+ void BN_BLINDING_set_thread_id(BN_BLINDING *, unsigned long);
+ unsigned long BN_BLINDING_get_flags(const BN_BLINDING *);
+ void BN_BLINDING_set_flags(BN_BLINDING *, unsigned long);
+ BN_BLINDING *BN_BLINDING_create_param(BN_BLINDING *b,
+	const BIGNUM *e, BIGNUM *m, BN_CTX *ctx,
+	int (*bn_mod_exp)(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
+			  const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx),
+	BN_MONT_CTX *m_ctx);
 
 =head1 DESCRIPTION