BN_BLINDING_convert_ex(3)

BN_BLINDING_new(3)           OpenSSL           BN_BLINDING_new(3)

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_thread_id, BN_BLINDING_get_flags,
     BN_BLINDING_set_flags, BN_BLINDING_create_param - blinding
     related BIGNUM functions.

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);
      #ifndef OPENSSL_NO_DEPRECATED
      unsigned long BN_BLINDING_get_thread_id(const BN_BLINDING *);
      void BN_BLINDING_set_thread_id(BN_BLINDING *, unsigned long);
      #endif
      CRYPTO_THREADID *BN_BLINDING_thread_id(BN_BLINDING *);
      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);

DESCRIPTION

     BN_BLINDING_new() allocates a new BN_BLINDING structure and
     copies the A and Ai values into the newly created
     BN_BLINDING object.

     BN_BLINDING_free() frees the BN_BLINDING structure.

     BN_BLINDING_update() updates the BN_BLINDING parameters by
     squaring the A and 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 n with the blinding
     factor A.  If r is not NULL a copy the inverse blinding
     factor Ai will be returned in r (this is useful if a RSA
     object is shared among several threads).
     BN_BLINDING_invert_ex() multiplies n with the inverse

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BN_BLINDING_new(3)           OpenSSL           BN_BLINDING_new(3)

     blinding factor Ai. If 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 r set to NULL.

     BN_BLINDING_thread_id() provides access to the
     CRYPTO_THREADID object within the BN_BLINDING structure.
     This is to help users provide proper locking if needed for
     multi-threaded use. The "thread id" object of a newly
     allocated BN_BLINDING structure is initialised to the thread
     id in which BN_BLINDING_new() was called.

     BN_BLINDING_get_flags() returns the BN_BLINDING flags.
     Currently there are two supported flags:
     BN_BLINDING_NO_UPDATE and BN_BLINDING_NO_RECREATE.
     BN_BLINDING_NO_UPDATE inhibits the automatic update of the
     BN_BLINDING parameters after each use and
     BN_BLINDING_NO_RECREATE inhibits the automatic re-creation
     of the BN_BLINDING parameters after a fixed number of uses
     (currently 32). In newly allocated BN_BLINDING objects no
     flags are set.  BN_BLINDING_set_flags() sets the BN_BLINDING
     parameters flags.

     BN_BLINDING_create_param() creates new BN_BLINDING
     parameters using the exponent e and the modulus m.
     bn_mod_exp and m_ctx can be used to pass special functions
     for exponentiation (normally BN_mod_exp_mont() and
     BN_MONT_CTX).

RETURN VALUES

     BN_BLINDING_new() returns the newly allocated 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 occurred.

     BN_BLINDING_thread_id() returns a pointer to the thread id
     object within a BN_BLINDING object.

     BN_BLINDING_get_flags() returns the currently set
     BN_BLINDING flags (a unsigned long value).

     BN_BLINDING_create_param() returns the newly created
     BN_BLINDING parameters or NULL on error.

SEE ALSO

     bn(3)

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BN_BLINDING_new(3)           OpenSSL           BN_BLINDING_new(3)

HISTORY

     BN_BLINDING_thread_id was first introduced in OpenSSL 1.0.0,
     and it deprecates BN_BLINDING_set_thread_id and
     BN_BLINDING_get_thread_id.

     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

AUTHOR

     Nils Larsch for the OpenSSL project
     (http://www.openssl.org).

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