Add description of SSL_[CTX_]_check_private_key().

doc/ssl/SSL_CTX_use_certificate.pod

@@ -2,7 +2,7 @@
 
 =head1 NAME
 
-SSL_CTX_use_certificate, SSL_CTX_use_certificate_ASN1, SSL_CTX_use_certificate_file, SSL_use_certificate, SSL_use_certificate_ASN1, SSL_use_certificate_file, SSL_CTX_use_certificate_chain_file, SSL_CTX_use_PrivateKey, SSL_CTX_use_PrivateKey_ASN1, SSL_CTX_use_PrivateKey_file, SSL_CTX_use_RSAPrivateKey, SSL_CTX_use_RSAPrivateKey_ASN1, SSL_CTX_use_RSAPrivateKey_file, SSL_use_PrivateKey_file, SSL_use_PrivateKey_ASN1, SSL_use_PrivateKey, SSL_use_RSAPrivateKey, SSL_use_RSAPrivateKey_ASN1, SSL_use_RSAPrivateKey_file - load certificate and key data
+SSL_CTX_use_certificate, SSL_CTX_use_certificate_ASN1, SSL_CTX_use_certificate_file, SSL_use_certificate, SSL_use_certificate_ASN1, SSL_use_certificate_file, SSL_CTX_use_certificate_chain_file, SSL_CTX_use_PrivateKey, SSL_CTX_use_PrivateKey_ASN1, SSL_CTX_use_PrivateKey_file, SSL_CTX_use_RSAPrivateKey, SSL_CTX_use_RSAPrivateKey_ASN1, SSL_CTX_use_RSAPrivateKey_file, SSL_use_PrivateKey_file, SSL_use_PrivateKey_ASN1, SSL_use_PrivateKey, SSL_use_RSAPrivateKey, SSL_use_RSAPrivateKey_ASN1, SSL_use_RSAPrivateKey_file, SSL_CTX_check_private_key, SSL_check_private_key- load certificate and key data
 
 =head1 SYNOPSIS
 
@@ -31,6 +31,9 @@ SSL_CTX_use_certificate, SSL_CTX_use_certificate_ASN1, SSL_CTX_use_certificate_f
  int SSL_use_RSAPrivateKey_ASN1(SSL *ssl, unsigned char *d, long len);
  int SSL_use_RSAPrivateKey_file(SSL *ssl, const char *file, int type);
 
+ int SSL_CTX_check_private_key(SSL_CTX *ctx);
+ int SSL_check_private_key(SSL *ssl);
+
 =head1 DESCRIPTION
 
 These functions load the certificates and private keys into the SSL_CTX
@@ -82,6 +85,14 @@ B<file> to B<ctx>. SSL_use_PrivateKey_file() adds the first private key found
 in B<file> to B<ssl>; SSL_use_RSAPrivateKey_file() adds the first private
 RSA key found to B<ssl>.
 
+SSL_CTX_check_private_key() checks the consistency of a private key with
+the corresponding certificate loaded into B<ctx>. If more than one
+key/certificate pair (RSA/DSA) is installed, the last item installed will
+be checked. If e.g. the last item was a RSA certificate or key, the RSA
+key/certificate pair will be checked. SSL_check_private_key() performs
+the same check for B<ssl>. If no key/certificate was explicitly added for
+this B<ssl>, the last item added into B<ctx> will be checked.
+
 =head1 NOTES
   
 The internal certificate store of OpenSSL can hold two private key/certificate