RSA_sign, RSA_verify - RSA signatures
#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);
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.
Note that PKCS #1 adds meta-data, placing limits on the size of the
key that can be used.
See RSA_private_encrypt for lower-level
operations.
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 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.
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.
Certain signatures with an improper algorithm identifier are accepted for compatibility with SSLeay 0.4.5 :-)
SSL, PKCS #1 v2.0
ERR_get_error, objects, rsa, RSA_private_encrypt, RSA_public_decrypt
RSA_sign() and RSA_verify() are available in all versions of SSLeay
and OpenSSL.