doc/: Mention that OpenSSL < 1.0.2 only supports a single curve at a time

1 files changed, 1 insertions, 1 deletions

diff --git a/doc/luaossl.tex b/doc/luaossl.tex
index 72f4d06..32a4dba 100644
--- a/doc/luaossl.tex
+++ b/doc/luaossl.tex
@@ -893,7 +893,7 @@ Sets the supported curves. The string format is a list of colon separated curve
 
 Sets \module{openssl.pkey} object $key$ as the ephemeral key during key exchanges which use that particular key type. Typically $key$ will be either a Diffie-Hellman or Elliptic Curve key.
 
-\emph{In order to configure an SSL server to support an ephemeral key exchange cipher suite (i.e. DHE-* and ECDHE-*), the application must explicitly set the ephemeral keys. Simply enabling the cipher suite is not sufficient. The application can statically generate Diffie-Hellman public key parameters, and many servers ship with such a key compiled into the software. Elliptic curve keys are necessarily static, and instantiated by curve name\footnote{\href{http://en.wikipedia.org/w/index.php?title=Comparison\_of\_TLS\_implementations&oldid=629779090\#Supported\_elliptic\_curves}{According to Wikipedia} the most widely supported curve is prime256v1, so to enable ECDHE-* applications can simply do \texttt{ctx:setEphemeralKey(pkey.new\{ type = ``EC'', curve = ``prime256v1'' \})}. To achieve Perfect Forward Secrecy for ECDHE-*, applications must also do \texttt{ctx:setOptions(context.OP\_SINGLE\_ECDH\_USE)}. The \texttt{ctx} object must then be used to configure each SSL session, such as by passing it to \fn{cqueues.socket:starttls()}.}.}
+\emph{In order to configure an SSL server to support an ephemeral key exchange cipher suite (i.e. DHE-* and ECDHE-*), the application must explicitly set the ephemeral keys. Simply enabling the cipher suite is not sufficient. The application can statically generate Diffie-Hellman public key parameters, and many servers ship with such a key compiled into the software. Elliptic curve keys are necessarily static, and instantiated by curve name\footnote{OpenSSL < 1.0.2 only supports a single curve, \href{http://en.wikipedia.org/w/index.php?title=Comparison\_of\_TLS\_implementations&oldid=629779090\#Supported\_elliptic\_curves}{according to Wikipedia} the most widely supported curve is prime256v1, so to enable ECDHE-*, applications can simply do \texttt{ctx:setEphemeralKey(pkey.new\{ type = ``EC'', curve = ``prime256v1'' \})}. To achieve Perfect Forward Secrecy for ECDHE-*, applications must also do \texttt{ctx:setOptions(context.OP\_SINGLE\_ECDH\_USE)}. The \texttt{ctx} object must then be used to configure each SSL session, such as by passing it to \fn{cqueues.socket:starttls()}.}.}
 
 \emph{In addition, to attain Perfect Forward Secrecy the options \texttt{OP\_SINGLE\_DH\_USE} and \texttt{OP\_SINGLE\_ECDH\_USE} must be set so that OpenSSL discards and regenerates the secret keying parameters for each key exchange.}