RSA_padding_add_PKCS1_type_1(3)

     NAME
          RSA_padding_add_PKCS1_type_1,
          RSA_padding_check_PKCS1_type_1,
          RSA_padding_add_PKCS1_type_2,
          RSA_padding_check_PKCS1_type_2, RSA_padding_add_PKCS1_OAEP,
          RSA_padding_check_PKCS1_OAEP, RSA_padding_add_SSLv23,
          RSA_padding_check_SSLv23, RSA_padding_add_none,
          RSA_padding_check_none - asymmetric encryption padding

     SYNOPSIS
           #include <openssl/rsa.h>

           int RSA_padding_add_PKCS1_type_1(unsigned char *to, int tlen,
              unsigned char *f, int fl);

           int RSA_padding_check_PKCS1_type_1(unsigned char *to, int tlen,
              unsigned char *f, int fl, int rsa_len);

           int RSA_padding_add_PKCS1_type_2(unsigned char *to, int tlen,
              unsigned char *f, int fl);

           int RSA_padding_check_PKCS1_type_2(unsigned char *to, int tlen,
              unsigned char *f, int fl, int rsa_len);

           int RSA_padding_add_PKCS1_OAEP(unsigned char *to, int tlen,
              unsigned char *f, int fl, unsigned char *p, int pl);

           int RSA_padding_check_PKCS1_OAEP(unsigned char *to, int tlen,
              unsigned char *f, int fl, int rsa_len, unsigned char *p, int pl);

           int RSA_padding_add_SSLv23(unsigned char *to, int tlen,
              unsigned char *f, int fl);

           int RSA_padding_check_SSLv23(unsigned char *to, int tlen,
              unsigned char *f, int fl, int rsa_len);

           int RSA_padding_add_none(unsigned char *to, int tlen,
              unsigned char *f, int fl);

           int RSA_padding_check_none(unsigned char *to, int tlen,
              unsigned char *f, int fl, int rsa_len);


     DESCRIPTION
          The RSA_padding_xxx_xxx() functions are called from the RSA
          encrypt, decrypt, sign and verify functions. Normally they
          should not be called from application programs.

          However, they can also be called directly to implement
          padding for other asymmetric ciphers.
          RSA_padding_add_PKCS1_OAEP() and
          RSA_padding_check_PKCS1_OAEP() may be used in an application
          combined with RSA_NO_PADDING in order to implement OAEP with
          an encoding parameter.

          RSA_padding_add_xxx() encodes fl bytes from f so as to fit
          into tlen bytes and stores the result at to. An error occurs
          if fl does not meet the size requirements of the encoding
          method.

          The following encoding methods are implemented:

          PKCS1_type_1
              PKCS #1 v2.0 EMSA-PKCS1-v1_5 (PKCS #1 v1.5 block type
              1); used for signatures

          PKCS1_type_2
              PKCS #1 v2.0 EME-PKCS1-v1_5 (PKCS #1 v1.5 block type 2)

          PKCS1_OAEP
              PKCS #1 v2.0 EME-OAEP

          SSLv23
              PKCS #1 EME-PKCS1-v1_5 with SSL-specific modification

          none
              simply copy the data

          The random number generator must be seeded prior to calling
          RSA_padding_add_xxx().

          RSA_padding_check_xxx() verifies that the fl bytes at f
          contain a valid encoding for a rsa_len byte RSA key in the
          respective encoding method and stores the recovered data of
          at most tlen bytes (for RSA_NO_PADDING: of size tlen) at to.

          For RSA_padding_xxx_OAEP(), p points to the encoding
          parameter of length pl. p may be NULL if pl is 0.

     RETURN VALUES
          The RSA_padding_add_xxx() functions return 1 on success, 0
          on error.  The RSA_padding_check_xxx() functions return the
          length of the recovered data, -1 on error. Error codes can
          be obtained by calling ERR_get_error(3).

     SEE ALSO
          RSA_public_encrypt(3), RSA_private_decrypt(3), RSA_sign(3),
          RSA_verify(3)

     HISTORY
          RSA_padding_add_PKCS1_type_1(),
          RSA_padding_check_PKCS1_type_1(),
          RSA_padding_add_PKCS1_type_2(),
          RSA_padding_check_PKCS1_type_2(), RSA_padding_add_SSLv23(),
          RSA_padding_check_SSLv23(), RSA_padding_add_none() and
          RSA_padding_check_none() appeared in SSLeay 0.9.0.

          RSA_padding_add_PKCS1_OAEP() and
          RSA_padding_check_PKCS1_OAEP() were added in OpenSSL 0.9.2b.