RSA_set_method(3) - NetBSD Manual Pages

RSA_set_method(3)            OpenSSL            RSA_set_method(3)



NAME

       RSA_set_default_method, RSA_get_default_method,
       RSA_set_method, RSA_get_method, RSA_PKCS1_SSLeay,
       RSA_PKCS1_RSAref, RSA_null_method, RSA_flags,
       RSA_new_method - select RSA method


LIBRARY

       libcrypto, -lcrypto


SYNOPSIS

        #include <openssl/rsa.h>

        void RSA_set_default_method(RSA_METHOD *meth);

        RSA_METHOD *RSA_get_default_method(void);

        RSA_METHOD *RSA_set_method(RSA *rsa, RSA_METHOD *meth);

        RSA_METHOD *RSA_get_method(RSA *rsa);

        RSA_METHOD *RSA_PKCS1_SSLeay(void);

        RSA_METHOD *RSA_PKCS1_RSAref(void);

        RSA_METHOD *RSA_null_method(void);

        int RSA_flags(RSA *rsa);

        RSA *RSA_new_method(RSA_METHOD *method);



DESCRIPTION

       An RSA_METHOD specifies the functions that OpenSSL uses
       for RSA operations. By modifying the method, alternative
       implementations such as hardware accelerators may be used.

       Initially, the default is to use the OpenSSL internal
       implementation, unless OpenSSL was configured with the
       `rsaref' or `-DRSA_NULL' options. RSA_PKCS1_SSLeay()
       returns a pointer to that method.

       RSA_PKCS1_RSAref() returns a pointer to a method that uses
       the RSAref library. This is the default method in the
       `rsaref' configuration; the function is not available in
       other configurations.  RSA_null_method() returns a pointer
       to a method that does not support the RSA transformation.
       It is the default if OpenSSL is compiled with
       `-DRSA_NULL'. These methods may be useful in the USA
       because of a patent on the RSA cryptosystem.

       RSA_set_default_method() makes meth the default method for
       all RSA structures created later.

       RSA_get_default_method() returns a pointer to the current



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RSA_set_method(3)            OpenSSL            RSA_set_method(3)


       default method.

       RSA_set_method() selects meth for all operations using the
       key rsa.

       RSA_get_method() returns a pointer to the method currently
       selected for rsa.

       RSA_flags() returns the flags that are set for rsa's cur-
       rent method.

       RSA_new_method() allocates and initializes an RSA struc-
       ture so that method will be used for the RSA operations.
       If method is NULL, the default method is used.


THE RSA_METHOD STRUCTURE

        typedef struct rsa_meth_st
        {
            /* name of the implementation */
               const char *name;

            /* encrypt */
               int (*rsa_pub_enc)(int flen, unsigned char *from,
                 unsigned char *to, RSA *rsa, int padding);

            /* verify arbitrary data */
               int (*rsa_pub_dec)(int flen, unsigned char *from,
                 unsigned char *to, RSA *rsa, int padding);

            /* sign arbitrary data */
               int (*rsa_priv_enc)(int flen, unsigned char *from,
                 unsigned char *to, RSA *rsa, int padding);

            /* decrypt */
               int (*rsa_priv_dec)(int flen, unsigned char *from,
                 unsigned char *to, RSA *rsa, int padding);

            /* compute r0 = r0 ^ I mod rsa->n (May be NULL for some
                                               implementations) */
               int (*rsa_mod_exp)(BIGNUM *r0, BIGNUM *I, RSA *rsa);

            /* compute r = a ^ p mod m (May be NULL for some implementations) */
               int (*bn_mod_exp)(BIGNUM *r, BIGNUM *a, const BIGNUM *p,
                 const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx);

            /* called at RSA_new */
               int (*init)(RSA *rsa);

            /* called at RSA_free */
               int (*finish)(RSA *rsa);







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RSA_set_method(3)            OpenSSL            RSA_set_method(3)


            /* RSA_FLAG_EXT_PKEY        - rsa_mod_exp is called for private key
             *                            operations, even if p,q,dmp1,dmq1,iqmp
             *                            are NULL
             * RSA_FLAG_SIGN_VER        - enable rsa_sign and rsa_verify
             * RSA_METHOD_FLAG_NO_CHECK - don't check pub/private match
             */
               int flags;

               char *app_data; /* ?? */

            /* sign. For backward compatibility, this is used only
             * if (flags & RSA_FLAG_SIGN_VER)
             */
               int (*rsa_sign)(int type, unsigned char *m, unsigned int m_len,
                  unsigned char *sigret, unsigned int *siglen, RSA *rsa);

            /* verify. For backward compatibility, this is used only
             * if (flags & RSA_FLAG_SIGN_VER)
             */
               int (*rsa_verify)(int type, unsigned char *m, unsigned int m_len,
                  unsigned char *sigbuf, unsigned int siglen, RSA *rsa);

        } RSA_METHOD;



RETURN VALUES

       RSA_PKCS1_SSLeay(), RSA_PKCS1_RSAref(),
       RSA_PKCS1_null_method(), RSA_get_default_method() and
       RSA_get_method() return pointers to the respective
       RSA_METHODs.

       RSA_set_default_method() returns no value.

       RSA_set_method() returns a pointer to the RSA_METHOD pre-
       viously associated with rsa.

       RSA_new_method() returns NULL and sets an error code that
       can be obtained by ERR_get_error(3) if the allocation
       fails. Otherwise it returns a pointer to the newly allo-
       cated structure.


SEE ALSO

       openssl_rsa(3), RSA_new(3)


HISTORY

       RSA_new_method() and RSA_set_default_method() appeared in
       SSLeay 0.8.  RSA_get_default_method(), RSA_set_method()
       and RSA_get_method() as well as the rsa_sign and rsa_ver-
       ify components of RSA_METHOD were added in OpenSSL 0.9.4.








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