=pod
=head1 NAME
rsa - RSA public key cryptosystem
=head1 SYNOPSIS
#include <openssl/rsa.h>
RSA * RSA_new(void);
void RSA_free(RSA *rsa);
int RSA_public_encrypt(int flen, unsigned char *from,
unsigned char *to, RSA *rsa, int padding);
int RSA_private_decrypt(int flen, unsigned char *from,
unsigned char *to, RSA *rsa, int padding);
int RSA_sign(int type, unsigned char *m, unsigned int m_len,
unsigned char *sigret, unsigned int *siglen, RSA *rsa);
int RSA_verify(int type, unsigned char *m, unsigned int m_len,
unsigned char *sigbuf, unsigned int siglen, RSA *rsa);
int RSA_size(RSA *rsa);
RSA *RSA_generate_key(int num, unsigned long e,
void (*callback)(int,int,void *), void *cb_arg);
int RSA_check_key(RSA *rsa);
int RSA_blinding_on(RSA *rsa, BN_CTX *ctx);
void RSA_blinding_off(RSA *rsa);
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);
int RSA_print(BIO *bp, RSA *x, int offset);
int RSA_print_fp(FILE *fp, RSA *x, int offset);
int RSA_get_ex_new_index(long argl, char *argp, int (*new_func)(),
int (*dup_func)(), void (*free_func)());
int RSA_set_ex_data(RSA *r,int idx,char *arg);
char *RSA_get_ex_data(RSA *r, int idx);
int RSA_private_encrypt(int flen, unsigned char *from,
unsigned char *to, RSA *rsa,int padding);
int RSA_public_decrypt(int flen, unsigned char *from,
unsigned char *to, RSA *rsa,int padding);
int RSA_sign_ASN1_OCTET_STRING(int dummy, unsigned char *m,
unsigned int m_len, unsigned char *sigret, unsigned int *siglen,
RSA *rsa);
int RSA_verify_ASN1_OCTET_STRING(int dummy, unsigned char *m,
unsigned int m_len, unsigned char *sigbuf, unsigned int siglen,
RSA *rsa);
=head1 DESCRIPTION
These functions implement RSA public key encryption and signatures
as defined in PKCS #1 v2.0 [RFC 2437].
The B<RSA> structure consists of several BIGNUM components. It can
contain public as well as private RSA keys:
struct
{
BIGNUM *n; // public modulus
BIGNUM *e; // public exponent
BIGNUM *d; // private exponent
BIGNUM *p; // secret prime factor
BIGNUM *q; // secret prime factor
BIGNUM *dmp1; // d mod (p-1)
BIGNUM *dmq1; // d mod (q-1)
BIGNUM *iqmp; // q^-1 mod p
// ...
};
RSA
In public keys, the private exponent and the related secret values are
B<NULL>.
B<p>, B<q>, B<dmp1>, B<dmq1> and B<iqmp> may be B<NULL> in private
keys, but the RSA operations are much faster when these values are
available.
=head1 CONFORMING TO
SSL, PKCS #1 v2.0
=head1 PATENTS
RSA was covered by a US patent which expired in September 2000.
=head1 SEE ALSO
L<rsa(1)|rsa(1)>, L<bn(3)|bn(3)>, L<dsa(3)|dsa(3)>, L<dh(3)|dh(3)>,
L<rand(3)|rand(3)>, L<RSA_new(3)|RSA_new(3)>,
L<RSA_public_encrypt(3)|RSA_public_encrypt(3)>,
L<RSA_sign(3)|RSA_sign(3)>, L<RSA_size(3)|RSA_size(3)>,
L<RSA_generate_key(3)|RSA_generate_key(3)>,
L<RSA_check_key(3)|RSA_check_key(3)>,
L<RSA_blinding_on(3)|RSA_blinding_on(3)>,
L<RSA_set_method(3)|RSA_set_method(3)>, L<RSA_print(3)|RSA_print(3)>,
L<RSA_get_ex_new_index(3)|RSA_get_ex_new_index(3)>,
L<RSA_private_encrypt(3)|RSA_private_encrypt(3)>,
L<RSA_sign_ASN1_OCTET_STRING(3)|RSA_sign_ASN1_OCTET_STRING(3)>,
L<RSA_padding_add_PKCS1_type_1(3)|RSA_padding_add_PKCS1_type_1(3)>
=cut