free NULL cleanup.

[openssl.git] / doc / crypto / RSA_sign.pod

diff --git a/doc/crypto/RSA_sign.pod b/doc/crypto/RSA_sign.pod
index 08f0fe7068303dd15b0c722d46a896e5356879fc..fc16b1f4f8061509c5fb2608886010a56bf20a1d 100644 (file)
--- a/doc/crypto/RSA_sign.pod
+++ b/doc/crypto/RSA_sign.pod
@@ -8,10 +8,10 @@ RSA_sign, RSA_verify - RSA signatures
 
  #include <openssl/rsa.h>
 
- int RSA_sign(int type, unsigned char *m, unsigned int m_len,
+ 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, unsigned char *m, unsigned int m_len,
+ int RSA_verify(int type, const unsigned char *m, unsigned int m_len,
     unsigned char *sigbuf, unsigned int siglen, RSA *rsa);
 
 =head1 DESCRIPTION
@@ -19,11 +19,15 @@ RSA_sign, RSA_verify - RSA signatures
 RSA_sign() signs the message digest B<m> of size B<m_len> using the
 private key B<rsa> as specified in PKCS #1 v2.0. It stores the
 signature in B<sigret> and the signature size in B<siglen>. B<sigret>
-must point to B<RSA_size(rsa)> bytes of memory.
+must point to RSA_size(B<rsa>) bytes of memory.
+Note that PKCS #1 adds meta-data, placing limits on the size of the
+key that can be used.
+See L<RSA_private_encrypt(3)|RSA_private_encrypt(3)> for lower-level
+operations.
 
 B<type> denotes the message digest algorithm that was used to generate
-B<m>. It usually is one of B<NID_sha1>, B<NID_ripemd160> and
-B<NID_md5>; see L<objects(3)> for details. If B<type> is B<NID_md5_sha1>,
+B<m>. It usually is one of B<NID_sha1>, B<NID_ripemd160> and B<NID_md5>;
+see L<objects(3)|objects(3)> for details. If B<type> is B<NID_md5_sha1>,
 an SSL signature (MD5 and SHA1 message digests with PKCS #1 padding
 and no algorithm identifier) is created.
 
@@ -50,8 +54,8 @@ SSL, PKCS #1 v2.0
 
 =head1 SEE ALSO
 
-L<err(3)|err(3)>, L<objects(3)|objects(3)>, L<rsa(3)|rsa(3)>,
-L<RSA_private_encrypt(3)|RSA_private_encrypt(3)>,
+L<ERR_get_error(3)|ERR_get_error(3)>, L<objects(3)|objects(3)>,
+L<rsa(3)|rsa(3)>, L<RSA_private_encrypt(3)|RSA_private_encrypt(3)>,
 L<RSA_public_decrypt(3)|RSA_public_decrypt(3)> 
 
 =head1 HISTORY