5 RSA_set_default_method, RSA_get_default_method, RSA_set_method,
6 RSA_get_method, RSA_PKCS1_SSLeay, RSA_PKCS1_RSAref,
7 RSA_PKCS1_null_method, RSA_flags, RSA_new_method - Select RSA method
11 #include <openssl/rsa.h>
13 void RSA_set_default_method(RSA_METHOD *meth);
15 RSA_METHOD *RSA_get_default_method(void);
17 RSA_METHOD *RSA_set_method(RSA *rsa, RSA_METHOD *meth);
19 RSA_METHOD *RSA_get_method(RSA *rsa);
21 RSA_METHOD *RSA_PKCS1_SSLeay(void);
23 RSA_METHOD *RSA_PKCS1_RSAref(void);
25 RSA_METHOD *RSA_null_method(void);
27 int RSA_flags(RSA *rsa);
29 RSA *RSA_new_method(RSA_METHOD *method);
33 An B<RSA_METHOD> specifies the functions that OpenSSL uses for RSA
34 operations. By modifying the method, alternative implementations
35 such as hardware accelerators may be used.
37 Initially, the default is to use the OpenSSL internal implementation,
38 unless OpenSSL was configured with the C<rsaref> or C<-DRSA_NULL>
39 options. RSA_PKCS1_SSLeay() returns a pointer to that method.
41 RSA_PKCS1_RSAref() returns a pointer to a method that uses the RSAref
42 library. This is the default method in the C<rsaref> configuration;
43 the function is not available in other configurations.
44 RSA_null_method() returns a pointer to a method that does not support
45 the RSA transformation. It is the default if OpenSSL is compiled with
46 C<-DRSA_NULL>. These methods may be useful in the USA because of a
47 patent on the RSA cryptosystem.
49 RSA_set_default_method() makes B<meth> the default method for all B<RSA>
50 structures created later.
52 RSA_get_default_method() returns a pointer to the current default
55 RSA_set_method() selects B<meth> for all operations using the key
58 RSA_get_method() returns a pointer to the method currently selected
61 RSA_flags() returns the B<flags> that are set for B<rsa>'s current method.
63 RSA_new_method() allocates and initializes an B<RSA> structure so that
64 B<method> will be used for the RSA operations. If B<method> is B<NULL>,
65 the default method is used.
67 =head1 THE RSA_METHOD STRUCTURE
69 typedef struct rsa_meth_st
71 /* name of the implementation */
75 int (*rsa_pub_enc)(int flen, unsigned char *from,
76 unsigned char *to, RSA *rsa, int padding);
78 /* verify arbitrary data */
79 int (*rsa_pub_dec)(int flen, unsigned char *from,
80 unsigned char *to, RSA *rsa, int padding);
82 /* sign arbitrary data */
83 int (*rsa_priv_enc)(int flen, unsigned char *from,
84 unsigned char *to, RSA *rsa, int padding);
87 int (*rsa_priv_dec)(int flen, unsigned char *from,
88 unsigned char *to, RSA *rsa, int padding);
90 /* compute r0 = r0 ^ I mod rsa->n. May be NULL */
91 int (*rsa_mod_exp)(BIGNUM *r0, BIGNUM *I, RSA *rsa);
93 /* compute r = a ^ p mod m. May be NULL */
94 int (*bn_mod_exp)(BIGNUM *r, BIGNUM *a, const BIGNUM *p,
95 const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx);
97 /* called at RSA_new */
98 int (*init)(RSA *rsa);
100 /* called at RSA_free */
101 int (*finish)(RSA *rsa);
103 /* RSA_FLAG_EXT_PKEY - rsa_mod_exp is called for private key
104 * operations, even if p,q,dmp1,dmq1,iqmp
106 * RSA_FLAG_SIGN_VER - enable rsa_sign and rsa_verify
107 * RSA_METHOD_FLAG_NO_CHECK - don't check pub/private match
111 char *app_data; /* ?? */
113 /* sign. For backward compatibility, this is used only
114 * if (flags & RSA_FLAG_SIGN_VER)
116 int (*rsa_sign)(int type, unsigned char *m, unsigned int m_len,
117 unsigned char *sigret, unsigned int *siglen, RSA *rsa);
119 /* verify. For backward compatibility, this is used only
120 * if (flags & RSA_FLAG_SIGN_VER)
122 int (*rsa_verify)(int type, unsigned char *m, unsigned int m_len,
123 unsigned char *sigbuf, unsigned int siglen, RSA *rsa);
129 RSA_PKCS1_SSLeay(), RSA_PKCS1_RSAref(), RSA_PKCS1_null_method(),
130 RSA_get_default_method() and RSA_get_method() return pointers to the
131 respective B<RSA_METHOD>s.
133 RSA_set_default_method() returns no value.
135 RSA_set_method() returns a pointer to the B<RSA_METHOD> previously
136 associated with B<rsa>.
138 RSA_new_method() returns B<NULL> and sets an error code that can be
139 obtained by L<ERR_get_error(3)|ERR_get_error(3)> if the allocation fails. Otherwise it
140 returns a pointer to the newly allocated structure.
144 L<rsa(3)|rsa(3)>, L<RSA_new(3)|RSA_new(3)>
148 RSA_new_method() and RSA_set_default_method() appeared in SSLeay 0.8.
149 RSA_get_default_method(), RSA_set_method() and RSA_get_method() as
150 well as the rsa_sign and rsa_verify components of RSA_METHOD were
151 added in OpenSSL 0.9.4.