Synopsis #include <openssl/rsa.h> 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);
DESCRIPTIONRSA_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 identifier) 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 VALUESRSA_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) .
RestrictionsCertain signatures with an improper algorithm identifier are
accepted for compatibility with SSLeay 0.4.5 :-) CONFORMING TOSSL, PKCS #1 v2.0 SEE ALSOERR_get_error(3) , objects(3) , rsa(3) , RSA_private_encrypt(3) , RSA_public_decrypt(3) HISTORYRSA_sign() and RSA_verify() are available in all versions
of SSLeay and OpenSSL.
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