RSA_sign(3)                         OpenSSL                        RSA_sign(3)



NAME
       RSA_sign, RSA_verify - RSA signatures

LIBRARY
       libcrypto, -lcrypto

SYNOPSIS
        #include <openssl/rsa.h>

        int RSA_sign(int type, const unsigned char *m, unsigned int m_len,
           unsigned char *sigret, unsigned int *siglen, RSA *rsa);

        int RSA_verify(int type, const unsigned char *m, unsigned int m_len,
           unsigned char *sigbuf, unsigned int siglen, RSA *rsa);

DESCRIPTION
       RSA_sign() signs the message digest m of size m_len using the private
       key rsa as specified in PKCS #1 v2.0. It stores the signature in sigret
       and the signature size in siglen. sigret must point to RSA_size(rsa)
       bytes of memory.

       type denotes the message digest algorithm that was used to generate m.
       It usually is one of NID_sha1, NID_ripemd160 and NID_md5; see
       objects(3) for details. If type is NID_md5_sha1, an SSL signature (MD5
       and SHA1 message digests with PKCS #1 padding and no algorithm identi-
       fier) is created.

       RSA_verify() verifies that the signature sigbuf of size siglen matches
       a given message digest m of size m_len. type denotes the message digest
       algorithm that was used to generate the signature.  rsa is the signer's
       public key.

RETURN VALUES
       RSA_sign() returns 1 on success, 0 otherwise.  RSA_verify() returns 1
       on successful verification, 0 otherwise.

       The error codes can be obtained by ERR_get_error(3).

BUGS
       Certain signatures with an improper algorithm identifier are accepted
       for compatibility with SSLeay 0.4.5 :-)

CONFORMING TO
       SSL, PKCS #1 v2.0

SEE ALSO
       ERR_get_error(3), objects(3), openssl_rsa(3), RSA_private_encrypt(3),
       RSA_public_decrypt(3)

HISTORY
       RSA_sign() and RSA_verify() are available in all versions of SSLeay and
       OpenSSL.



0.9.9-dev                         2005-11-24                       RSA_sign(3)
