#include <openssl/ssl.h>
- void SSL_CTX_set_cert_verify_callback(SSL_CTX *ctx, int (*callback)(),
- char *arg);
- int (*callback)();
+ void SSL_CTX_set_cert_verify_callback(SSL_CTX *ctx, int (*callback)(X509_STORE_CTX *,void *), void *arg);
=head1 DESCRIPTION
SSL_CTX_set_cert_verify_callback() sets the verification callback function for
-B<ctx>. SSL objects, that are created from B<ctx> inherit the setting valid at
-the time, L<SSL_new(3)|SSL_new(3)> is called. B<arg> is currently ignored.
+I<ctx>. SSL objects that are created from I<ctx> inherit the setting valid at
+the time when L<SSL_new(3)> is called.
=head1 NOTES
Whenever a certificate is verified during a SSL/TLS handshake, a verification
function is called. If the application does not explicitly specify a
verification callback function, the built-in verification function is used.
-If a verification callback B<callback> is specified via
+If a verification callback I<callback> is specified via
SSL_CTX_set_cert_verify_callback(), the supplied callback function is called
-instead. By setting B<callback> to NULL, the default behaviour is restored.
+instead. By setting I<callback> to NULL, the default behaviour is restored.
-When the verification must be performed, B<callback> will be called with
-the argument callback(X509_STORE_CTX *x509_store_ctx). The arguments B<arg>
-that can be specified when setting B<callback> are currently ignored.
+When the verification must be performed, I<callback> will be called with
+the arguments callback(X509_STORE_CTX *x509_store_ctx, void *arg). The
+argument I<arg> is specified by the application when setting I<callback>.
-B<callback> should return 1 to indicate verification success and 0 to
-indicate verification failure. If SSL_VERIFY_PEER is set and B<callback>
+I<callback> should return 1 to indicate verification success and 0 to
+indicate verification failure. If SSL_VERIFY_PEER is set and I<callback>
returns 0, the handshake will fail. As the verification procedure may
allow to continue the connection in case of failure (by always returning 1)
the verification result must be set in any case using the B<error>
-member of B<x509_store_ctx>, so that the calling application will be informed
+member of I<x509_store_ctx> so that the calling application will be informed
about the detailed result of the verification procedure!
-Within B<x509_store_ctx>, B<callback> has access to the B<verify_callback>
-function set using L<SSL_CTX_set_verify(3)|SSL_CTX_set_verify(3)>.
+Within I<x509_store_ctx>, I<callback> has access to the I<verify_callback>
+function set using L<SSL_CTX_set_verify(3)>.
=head1 WARNINGS
Do not mix the verification callback described in this function with the
B<verify_callback> function called during the verification process. The
-latter is set using the L<SSL_CTX_set_verify(3)|SSL_CTX_set_verify(3)>
+latter is set using the L<SSL_CTX_set_verify(3)>
family of functions.
Providing a complete verification procedure including certificate purpose
=head1 BUGS
-It is possible to specify arguments to be passed to the verification callback.
-Currently they are however not passed but ignored.
-
-The B<callback> function is not specified via a prototype, so that no
-type checking takes place.
-
=head1 RETURN VALUES
SSL_CTX_set_cert_verify_callback() does not provide diagnostic information.
=head1 SEE ALSO
-L<ssl(3)|ssl(3)>, L<SSL_CTX_set_verify(3)|SSL_CTX_set_verify(3)>,
-L<SSL_get_verify_result(3)|SSL_get_verify_result(3)>,
-L<SSL_CTX_load_verify_locations(3)|SSL_CTX_load_verify_locations(3)>
+L<ssl(3)>, L<SSL_CTX_set_verify(3)>,
+L<SSL_get_verify_result(3)>,
+L<SSL_CTX_load_verify_locations(3)>
=cut
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