NAME
RSA_sign,
RSA_verify —
RSA signatures
SYNOPSIS
/* -lcrypto */
#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
using RSASSA-PKCS1-v1_5 as specified in RFC 3447. It stores the signature in
sigret and the signature size in
siglen. sigret must point to
RSA_size(rsa)
bytes of memory. Note that PKCS #1 adds meta-data, placing limits on the
size of the key that can be used. See
RSA_private_encrypt(3) for lower-level operations.
type denotes the message digest algorithm that was used to generate m. If type is NID_md5_sha1, an SSL signature (MD5 and SHA-1 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 VALUES
RSA_sign() returns 1 on success.
RSA_verify() returns 1 on successful
verification.
The error codes can be obtained by ERR_get_error(3).
SEE ALSO
RSA_meth_set_sign(3), RSA_new(3), RSA_private_encrypt(3), RSA_public_decrypt(3)
STANDARDS
SSL, PKCS #1 v2.0
HISTORY
RSA_sign() first appeared in SSLeay 0.4.4.
RSA_verify() first appeared in SSLeay 0.6.0. Both
functions have been available since OpenBSD 2.4.