diff options
Diffstat (limited to 'lib/ssl/doc/src/using_ssl.xml')
| -rw-r--r-- | lib/ssl/doc/src/using_ssl.xml | 115 |
1 files changed, 98 insertions, 17 deletions
diff --git a/lib/ssl/doc/src/using_ssl.xml b/lib/ssl/doc/src/using_ssl.xml index f84cd6e391..3ef33df719 100644 --- a/lib/ssl/doc/src/using_ssl.xml +++ b/lib/ssl/doc/src/using_ssl.xml @@ -22,7 +22,7 @@ </legalnotice> - <title>Using SSL API</title> + <title>Using SSL application API</title> <prepared></prepared> <responsible></responsible> <docno></docno> @@ -51,7 +51,7 @@ <section> <title>Minimal Example</title> - <note><p> The minimal setup is not the most secure setup of SSL.</p> + <note><p> The minimal setup is not the most secure setup of SSL/TLS/DTLS.</p> </note> <p>To set up client/server connections:</p> @@ -60,27 +60,27 @@ <code type="erl">1 server> ssl:start(). ok</code> - <p><em>Step 2:</em> Create an SSL listen socket:</p> + <p><em>Step 2:</em> Create an TLS listen socket: (To run DTLS add the option {protocol, dtls})</p> <code type="erl">2 server> {ok, ListenSocket} = ssl:listen(9999, [{certfile, "cert.pem"}, {keyfile, "key.pem"},{reuseaddr, true}]). {ok,{sslsocket, [...]}}</code> - <p><em>Step 3:</em> Do a transport accept on the SSL listen socket:</p> + <p><em>Step 3:</em> Do a transport accept on the TLS listen socket:</p> <code type="erl">3 server> {ok, Socket} = ssl:transport_accept(ListenSocket). {ok,{sslsocket, [...]}}</code> - <p><em>Step 4:</em> Start the client side:</p> + <p><em>Step 4:</em> Start the client side: </p> <code type="erl">1 client> ssl:start(). ok</code> - + <p> To run DTLS add the option {protocol, dtls} to third argument.</p> <code type="erl">2 client> {ok, Socket} = ssl:connect("localhost", 9999, [], infinity). {ok,{sslsocket, [...]}}</code> - <p><em>Step 5:</em> Do the SSL handshake:</p> + <p><em>Step 5:</em> Do the TLS handshake:</p> <code type="erl">4 server> ok = ssl:ssl_accept(Socket). ok</code> - <p><em>Step 6:</em> Send a message over SSL:</p> + <p><em>Step 6:</em> Send a message over TLS:</p> <code type="erl">5 server> ssl:send(Socket, "foo"). ok</code> @@ -92,7 +92,7 @@ ok</code> </section> <section> - <title>Upgrade Example</title> + <title>Upgrade Example - TLS only </title> <note><p>To upgrade a TCP/IP connection to an SSL connection, the client and server must agree to do so. The agreement @@ -125,24 +125,24 @@ ok</code> <code type="erl">4 server> inet:setopts(Socket, [{active, false}]). ok</code> - <p><em>Step 6:</em> Do the SSL handshake:</p> - <code type="erl">5 server> {ok, SSLSocket} = ssl:ssl_accept(Socket, [{cacertfile, "cacerts.pem"}, + <p><em>Step 6:</em> Do the TLS handshake:</p> + <code type="erl">5 server> {ok, TLSSocket} = ssl:ssl_accept(Socket, [{cacertfile, "cacerts.pem"}, {certfile, "cert.pem"}, {keyfile, "key.pem"}]). {ok,{sslsocket,[...]}}</code> - <p><em>Step 7:</em> Upgrade to an SSL connection. The client and server + <p><em>Step 7:</em> Upgrade to an TLS connection. The client and server must agree upon the upgrade. The server must call <c>ssl:accept/2</c> before the client calls <c>ssl:connect/3.</c></p> - <code type="erl">3 client>{ok, SSLSocket} = ssl:connect(Socket, [{cacertfile, "cacerts.pem"}, + <code type="erl">3 client>{ok, TLSSocket} = ssl:connect(Socket, [{cacertfile, "cacerts.pem"}, {certfile, "cert.pem"}, {keyfile, "key.pem"}], infinity). {ok,{sslsocket,[...]}}</code> - <p><em>Step 8:</em> Send a message over SSL:</p> - <code type="erl">4 client> ssl:send(SSLSocket, "foo"). + <p><em>Step 8:</em> Send a message over TLS:</p> + <code type="erl">4 client> ssl:send(TLSSocket, "foo"). ok</code> - <p><em>Step 9:</em> Set <c>active true</c> on the SSL socket:</p> - <code type="erl">4 server> ssl:setopts(SSLSocket, [{active, true}]). + <p><em>Step 9:</em> Set <c>active true</c> on the TLS socket:</p> + <code type="erl">4 server> ssl:setopts(TLSSocket, [{active, true}]). ok</code> <p><em>Step 10:</em> Flush the shell message queue to see that the message @@ -152,4 +152,85 @@ Shell got {ssl,{sslsocket,[...]},"foo"} ok</code> </section> </section> + + <section> + <title>Customizing cipher suits</title> + + <p>Fetch default cipher suite list for an TLS/DTLS version. Change default + to all to get all possible cipher suites.</p> + <code type="erl">1> Default = ssl:cipher_suites(default, 'tlsv1.2'). + [#{cipher => aes_256_gcm,key_exchange => ecdhe_ecdsa, + mac => aead,prf => sha384}, ....] +</code> + + <p>In OTP 20 it is desirable to remove all cipher suites + that uses rsa kexchange (removed from default in 21) </p> + <code type="erl">2> NoRSA = + ssl:filter_cipher_suites(Default, + [{key_exchange, fun(rsa) -> false; + (_) -> true end}]). + [...] + </code> + + <p> Pick just a few suites </p> + <code type="erl"> 3> Suites = + ssl:filter_cipher_suites(Default, + [{key_exchange, fun(ecdh_ecdsa) -> true; + (_) -> false end}, + {cipher, fun(aes_128_cbc) ->true; + (_) ->false end}]). + [#{cipher => aes_128_cbc,key_exchange => ecdh_ecdsa, + mac => sha256,prf => sha256}, + #{cipher => aes_128_cbc,key_exchange => ecdh_ecdsa,mac => sha, + prf => default_prf}] + </code> + + <p> Make some particular suites the most preferred, or least + preferred by changing prepend to append.</p> + <code type="erl"> 4>ssl:prepend_cipher_suites(Suites, Default). + [#{cipher => aes_128_cbc,key_exchange => ecdh_ecdsa, + mac => sha256,prf => sha256}, + #{cipher => aes_128_cbc,key_exchange => ecdh_ecdsa,mac => sha, + prf => default_prf}, + #{cipher => aes_256_cbc,key_exchange => ecdhe_ecdsa, + mac => sha384,prf => sha384}, ...] + </code> + </section> + + <section> + <title>Using an Engine Stored Key</title> + + <p>Erlang ssl application is able to use private keys provided + by OpenSSL engines using the following mechanism:</p> + + <code type="erl">1> ssl:start(). +ok</code> + + <p>Load a crypto engine, should be done once per engine used. For example + dynamically load the engine called <c>MyEngine</c>: + </p> + <code type="erl">2> {ok, EngineRef} = +crypto:engine_load(<<"dynamic">>, + [{<<"SO_PATH">>, "/tmp/user/engines/MyEngine"},<<"LOAD">>],[]). +{ok,#Ref<0.2399045421.3028942852.173962>} + </code> + + <p>Create a map with the engine information and the algorithm used by the engine:</p> + <code type="erl">3> PrivKey = + #{algorithm => rsa, + engine => EngineRef, + key_id => "id of the private key in Engine"}. + </code> + <p>Use the map in the ssl key option:</p> + <code type="erl">4> {ok, SSLSocket} = +ssl:connect("localhost", 9999, + [{cacertfile, "cacerts.pem"}, + {certfile, "cert.pem"}, + {key, PrivKey}], infinity). + </code> + + <p>See also <seealso marker="crypto:engine_load#engine_load"> crypto documentation</seealso> </p> + + </section> + </chapter> |