1 files changed, 20 insertions, 8 deletions

diff --git a/src/lib/libcrypto/doc/EVP_OpenInit.pod b/src/lib/libcrypto/doc/EVP_OpenInit.pod
index 50edb124e4..2e710da945 100644
--- a/src/lib/libcrypto/doc/EVP_OpenInit.pod
+++ b/src/lib/libcrypto/doc/EVP_OpenInit.pod
@@ -10,9 +10,9 @@ EVP_OpenInit, EVP_OpenUpdate, EVP_OpenFinal - EVP envelope decryption
 
  int EVP_OpenInit(EVP_CIPHER_CTX *ctx,EVP_CIPHER *type,unsigned char *ek,
                 int ekl,unsigned char *iv,EVP_PKEY *priv);
- void EVP_OpenUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out,
+ int EVP_OpenUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out,
          int *outl, unsigned char *in, int inl);
- void EVP_OpenFinal(EVP_CIPHER_CTX *ctx, unsigned char *out,
+ int EVP_OpenFinal(EVP_CIPHER_CTX *ctx, unsigned char *out,
          int *outl);
 
 =head1 DESCRIPTION
@@ -21,7 +21,7 @@ The EVP envelope routines are a high level interface to envelope
 decryption. They decrypt a public key encrypted symmetric key and
 then decrypt data using it.
 
-EVP_OpenInit() initialises a cipher context B<ctx> for decryption
+EVP_OpenInit() initializes a cipher context B<ctx> for decryption
 with cipher B<type>. It decrypts the encrypted symmetric key of length
 B<ekl> bytes passed in the B<ek> parameter using the private key B<priv>.
 The IV is supplied in the B<iv> parameter.
@@ -29,20 +29,32 @@ The IV is supplied in the B<iv> parameter.
 EVP_OpenUpdate() and EVP_OpenFinal() have exactly the same properties
 as the EVP_DecryptUpdate() and EVP_DecryptFinal() routines, as 
 documented on the L<EVP_EncryptInit(3)|EVP_EncryptInit(3)> manual
-page. 
+page.
+
+=head1 NOTES
+
+It is possible to call EVP_OpenInit() twice in the same way as
+EVP_DecryptInit(). The first call should have B<priv> set to NULL
+and (after setting any cipher parameters) it should be called again
+with B<type> set to NULL.
+
+If the cipher passed in the B<type> parameter is a variable length
+cipher then the key length will be set to the value of the recovered
+key length. If the cipher is a fixed length cipher then the recovered
+key length must match the fixed cipher length.
 
 =head1 RETURN VALUES
 
-EVP_OpenInit() returns -1 on error or an non zero integer (actually the
+EVP_OpenInit() returns 0 on error or a non zero integer (actually the
 recovered secret key size) if successful.
 
-EVP_SealUpdate() does not return a value.
+EVP_OpenUpdate() returns 1 for success or 0 for failure.
 
-EVP_SealFinal() returns 0 if the decrypt failed or 1 for success.
+EVP_OpenFinal() returns 0 if the decrypt failed or 1 for success.
 
 =head1 SEE ALSO
 
-L<evp(3)|evp(3)>,
+L<evp(3)|evp(3)>, L<rand(3)|rand(3)>,
 L<EVP_EncryptInit(3)|EVP_EncryptInit(3)>,
 L<EVP_SealInit(3)|EVP_SealInit(3)>