Better documentation of -www,-WWW,-HTTP flags

[openssl.git] / doc / man1 / openssl.pod

diff --git a/doc/man1/openssl.pod b/doc/man1/openssl.pod
index 2e58b1bb3e9856d32434fae76a78b3383de646b1..dfa7a3bf7cae2dbcfdb8a8154dd70fef23181309 100644 (file)
--- a/doc/man1/openssl.pod
+++ b/doc/man1/openssl.pod
@@ -933,6 +933,50 @@ name.
 
 =back
 
+=head2 TLS Version Options
+
+Several commands use SSL, TLS, or DTLS. By default, the commands use TLS and
+clients will offer the lowest and highest protocol version they support,
+and servers will pick the highest version that the client offers that is also
+supported by the server.
+
+The options below can be used to limit which protocol versions are used,
+and whether TCP (SSL and TLS) or UDP (DTLS) is used.
+Note that not all protocols and flags may be available, depending on how
+OpenSSL was built.
+
+=over 4
+
+=item B<-ssl3>, B<-tls1>, B<-tls1_1>, B<-tls1_2>, B<-tls1_3>, B<-no_ssl3>, B<-no_tls1>, B<-no_tls1_1>, B<-no_tls1_2>, B<-no_tls1_3>
+
+These options require or disable the use of the specified SSL or TLS protocols.
+When a specific TLS version is required, only that version will be offered or
+accepted.
+Only one specific protocol can be given and it cannot be combined with any of
+the B<no_> options.
+
+=item B<-dtls>, B<-dtls1>, B<-dtls1_2>
+
+These options specify to use DTLS instead of DLTS.
+With B<-dtls>, clients will negotiate any supported DTLS protocol version.
+Use the B<-dtls1> or B<-dtls1_2> options to support only DTLS1.0 or DTLS1.2,
+respectively.
+
+=back
+
+=head2 Engine Options
+
+=over 4
+
+=item B<-engine> I<id>
+
+Use the engine identified by I<id> and use all the methods it
+implements (algorithms, key storage, etc.), unless specified otherwise in
+the command-specific documentation or it is configured to do so, as described
+in L<config(5)/Engine Configuration Module>.
+
+=back
+
 =head1 ENVIRONMENT
 
 The OpenSSL library can be take some configuration parameters from the