Allow ECDHE and DHE as forward-compatible aliases for EECDH and EDH

see RT #3203

Future versions of OpenSSL use the canonical terms "ECDHE" and "DHE"
as configuration strings and compilation constants.  This patch
introduces aliases so that the stable 1.0.2 branch can be
forward-compatible with code and configuration scripts that use the
normalized terms, while avoiding changing any library output for
stable users.

Signed-off-by: Kurt Roeckx <kurt@roeckx.be>
Reviewed-by: Matt Caswell <matt@openssl.org>

6 files changed, 20 insertions, 9 deletions

diff --git a/doc/apps/ciphers.pod b/doc/apps/ciphers.pod
index 695a7df12b..4eeb55be2c 100644
--- a/doc/apps/ciphers.pod
+++ b/doc/apps/ciphers.pod
@@ -177,12 +177,12 @@ cipher suites using RSA key exchange.
 cipher suites using DH key agreement and DH certificates signed by CAs with RSA
 and DSS keys or either respectively.
 
-=item B<kEDH>
+=item B<kDHE>, B<kEDH>
 
 cipher suites using ephemeral DH key agreement, including anonymous cipher
 suites.
 
-=item B<EDH>
+=item B<DHE>, B<EDH>
 
 cipher suites using authenticated ephemeral DH key agreement.
 
@@ -200,12 +200,12 @@ cipher suites using DH, including anonymous DH, ephemeral DH and fixed DH.
 cipher suites using fixed ECDH key agreement signed by CAs with RSA and ECDSA
 keys or either respectively.
 
-=item B<kEECDH>
+=item B<kECDHE>, B<kEECDH>
 
 cipher suites using ephemeral ECDH key agreement, including anonymous
 cipher suites.
 
-=item B<EECDHE>
+=item B<ECDHE>, B<EECDH>
 
 cipher suites using authenticated ephemeral ECDH key agreement.
 
diff --git a/doc/ssl/SSL_CIPHER_get_name.pod b/doc/ssl/SSL_CIPHER_get_name.pod
index 2e113be606..c598f4d4ce 100644
--- a/doc/ssl/SSL_CIPHER_get_name.pod
+++ b/doc/ssl/SSL_CIPHER_get_name.pod
@@ -109,6 +109,16 @@ If SSL_CIPHER_description() cannot handle a built-in cipher, the according
 description of the cipher property is B<unknown>. This case should not
 occur.
 
+The standard terminology for ephemeral Diffie-Hellman schemes is DHE
+(finite field) or ECDHE (elliptic curve).  This version of OpenSSL
+idiosyncratically reports these schemes as EDH and EECDH, even though
+it also accepts the standard terminology.
+
+It is recommended to use the standard terminology (DHE and ECDHE)
+during configuration (e.g. via SSL_CTX_set_cipher_list) for clarity of
+configuration.  OpenSSL versions after 1.0.2 will report the standard
+terms via SSL_CIPHER_get_name and SSL_CIPHER_description.
+
 =head1 RETURN VALUES
 
 See DESCRIPTION
@@ -116,6 +126,7 @@ See DESCRIPTION
 =head1 SEE ALSO
 
 L<ssl(3)|ssl(3)>, L<SSL_get_current_cipher(3)|SSL_get_current_cipher(3)>,
-L<SSL_get_ciphers(3)|SSL_get_ciphers(3)>, L<ciphers(1)|ciphers(1)>
+L<SSL_get_ciphers(3)|SSL_get_ciphers(3)>, L<ciphers(1)|ciphers(1)>,
+L<SSL_CTX_set_cipher_list(3)|SSL_CTX_set_cipher_list(3)>
 
 =cut
diff --git a/doc/ssl/SSL_CTX_set_cipher_list.pod b/doc/ssl/SSL_CTX_set_cipher_list.pod
index bd4df4abd4..c84a8314be 100644
--- a/doc/ssl/SSL_CTX_set_cipher_list.pod
+++ b/doc/ssl/SSL_CTX_set_cipher_list.pod
@@ -41,7 +41,7 @@ RSA export ciphers with a keylength of 512 bits for the RSA key require
 a temporary 512 bit RSA key, as typically the supplied key has a length
 of 1024 bit (see
 L<SSL_CTX_set_tmp_rsa_callback(3)|SSL_CTX_set_tmp_rsa_callback(3)>).
-RSA ciphers using EDH need a certificate and key and additional DH-parameters
+RSA ciphers using DHE need a certificate and key and additional DH-parameters
 (see L<SSL_CTX_set_tmp_dh_callback(3)|SSL_CTX_set_tmp_dh_callback(3)>).
 
 A DSA cipher can only be chosen, when a DSA certificate is available.
diff --git a/doc/ssl/SSL_CTX_set_options.pod b/doc/ssl/SSL_CTX_set_options.pod
index 6e6b5e6d80..7551755f6f 100644
--- a/doc/ssl/SSL_CTX_set_options.pod
+++ b/doc/ssl/SSL_CTX_set_options.pod
@@ -165,7 +165,7 @@ can only be used for signature operations (namely under export ciphers
 with restricted RSA keylength). By setting this option, ephemeral
 RSA keys are always used. This option breaks compatibility with the
 SSL/TLS specifications and may lead to interoperability problems with
-clients and should therefore never be used. Ciphers with EDH (ephemeral
+clients and should therefore never be used. Ciphers with DHE (ephemeral
 Diffie-Hellman) key exchange should be used instead.
 
 =item SSL_OP_CIPHER_SERVER_PREFERENCE
diff --git a/doc/ssl/SSL_CTX_set_tmp_rsa_callback.pod b/doc/ssl/SSL_CTX_set_tmp_rsa_callback.pod
index 534643cd9d..b23e43a963 100644
--- a/doc/ssl/SSL_CTX_set_tmp_rsa_callback.pod
+++ b/doc/ssl/SSL_CTX_set_tmp_rsa_callback.pod
@@ -70,7 +70,7 @@ the TLS standard, when the RSA key can be used for signing only, that is
 for export ciphers. Using ephemeral RSA key exchange for other purposes
 violates the standard and can break interoperability with clients.
 It is therefore strongly recommended to not use ephemeral RSA key
-exchange and use EDH (Ephemeral Diffie-Hellman) key exchange instead
+exchange and use DHE (Ephemeral Diffie-Hellman) key exchange instead
 in order to achieve forward secrecy (see
 L<SSL_CTX_set_tmp_dh_callback(3)|SSL_CTX_set_tmp_dh_callback(3)>).
 
diff --git a/doc/ssleay.txt b/doc/ssleay.txt
index 4d2e714868..c9b29bd97f 100644
--- a/doc/ssleay.txt
+++ b/doc/ssleay.txt
@@ -6026,7 +6026,7 @@ one at a time, or use 'aliases' to specify the preference and order for
 the ciphers.
 
 There are a large number of aliases, but the most importaint are
-kRSA, kDHr, kDHd and kEDH for key exchange types.
+kRSA, kDHr, kDHd and kDHE for key exchange types.
 
 aRSA, aDSS, aNULL and aDH for authentication
 DES, 3DES, RC4, RC2, IDEA and eNULL for ciphers