res/res_rtp_asterisk: Add ECDH support

This will add ECDH support to Asterisk. It will
detect auto ECDH support in OpenSSL
(1.0.2b and above) during ./configure. If this is
available, it will use it,
otherwise it will fall back to prime256v1 (this
behavior is consistent with
other projects such as Apache and nginx).

This fixes WebRTC being broken in Firefox 38+ due
to Firefox now only supporting
ciphers with perfect forward secrecy.

ASTERISK-25265 #close

Change-Id: I8c13b33a2a79c0bde2e69e4ba6afa5ab9351465b

1 files changed, 63 insertions, 0 deletions

diff --git a/configure b/configure
index 731b2f7a9..25bfc5869 100755
--- a/configure
+++ b/configure
@@ -1097,6 +1097,10 @@ PBX_DAHDI
 DAHDI_DIR
 DAHDI_INCLUDE
 DAHDI_LIB
+PBX_OPENSSL_ECDH_AUTO
+OPENSSL_ECDH_AUTO_DIR
+OPENSSL_ECDH_AUTO_INCLUDE
+OPENSSL_ECDH_AUTO_LIB
 PBX_OPENSSL_EC
 OPENSSL_EC_DIR
 OPENSSL_EC_INCLUDE
@@ -8706,6 +8710,18 @@ PBX_OPENSSL_EC=0
 
 
 
+OPENSSL_ECDH_AUTO_DESCRIP="OpenSSL Auto ECDH Support"
+OPENSSL_ECDH_AUTO_OPTION=crypto
+OPENSSL_ECDH_AUTO_DIR=${CRYPTO_DIR}
+
+PBX_OPENSSL_ECDH_AUTO=0
+
+
+
+
+
+
+
     DAHDI_DESCRIP="DAHDI"
     DAHDI_OPTION="dahdi"
     PBX_DAHDI=0
@@ -30529,6 +30545,53 @@ fi
 
 fi
 
+if test "$PBX_OPENSSL" = "1";
+then
+
+    if test "x${PBX_OPENSSL_ECDH_AUTO}" != "x1" -a "${USE_OPENSSL_ECDH_AUTO}" != "no"; then
+        { $as_echo "$as_me:${as_lineno-$LINENO}: checking for SSL_CTX_set_ecdh_auto declared in openssl/ssl.h" >&5
+$as_echo_n "checking for SSL_CTX_set_ecdh_auto declared in openssl/ssl.h... " >&6; }
+        saved_cppflags="${CPPFLAGS}"
+        if test "x${OPENSSL_ECDH_AUTO_DIR}" != "x"; then
+            OPENSSL_ECDH_AUTO_INCLUDE="-I${OPENSSL_ECDH_AUTO_DIR}/include"
+        fi
+        CPPFLAGS="${CPPFLAGS} ${OPENSSL_ECDH_AUTO_INCLUDE}"
+
+        cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+ #include <openssl/ssl.h>
+int
+main ()
+{
+#if !defined(SSL_CTX_set_ecdh_auto)
+                                    (void) SSL_CTX_set_ecdh_auto;
+                                #endif
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+     { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+$as_echo "yes" >&6; }
+                PBX_OPENSSL_ECDH_AUTO=1
+
+$as_echo "#define HAVE_OPENSSL_ECDH_AUTO 1" >>confdefs.h
+
+
+
+else
+     { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+
+        CPPFLAGS="${saved_cppflags}"
+    fi
+
+fi
+
 
 if test "x${PBX_SRTP}" != "x1" -a "${USE_SRTP}" != "no"; then
    pbxlibdir=""