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

diff --git a/configure b/configure
index e2cf9c94f30322b446f4e67030264298a3e7e9cd..a0468b9e5bded4429ca126e26050a998ba20d0b9 100755 (executable)
--- a/configure
+++ b/configure
@@ -1089,6 +1089,10 @@ 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
@@ -8696,6 +8700,18 @@ 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
@@ -30266,6 +30282,53 @@ 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=""

diff --git a/configure.ac b/configure.ac
index 971f9bf8a34d737e362042de08ecb12c69c64a7a..3292809247fdda36e1f9478927a776e94fdcfdc3 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -414,6 +414,7 @@ AST_EXT_LIB_SETUP([CRYPT], [password and data encryption], [crypt])
 AST_EXT_LIB_SETUP([CRYPTO], [OpenSSL Cryptography], [crypto])
 AST_EXT_LIB_SETUP_OPTIONAL([OPENSSL_SRTP], [OpenSSL SRTP Extension Support], [CRYPTO], [crypto])
 AST_EXT_LIB_SETUP_OPTIONAL([OPENSSL_EC], [OpenSSL Elliptic Curve Support], [CRYPTO], [crypto])
+AST_EXT_LIB_SETUP_OPTIONAL([OPENSSL_ECDH_AUTO], [OpenSSL Auto ECDH Support], [CRYPTO], [crypto])
 AST_EXT_LIB_SETUP([DAHDI], [DAHDI], [dahdi])
 AST_EXT_LIB_SETUP([FFMPEG], [Ffmpeg and avcodec], [avcodec])
 AST_EXT_LIB_SETUP([GSM], [External GSM], [gsm], [, use 'internal' GSM otherwise])
@@ -2283,6 +2284,11 @@ then
        AST_EXT_LIB_CHECK([OPENSSL_EC], [ssl], [EC_KEY_new_by_curve_name], [openssl/ec.h], [-lcrypto])
 fi
 
+if test "$PBX_OPENSSL" = "1";
+then
+        AST_C_DECLARE_CHECK([OPENSSL_ECDH_AUTO], [SSL_CTX_set_ecdh_auto], [openssl/ssl.h])
+fi
+
 AST_EXT_LIB_CHECK([SRTP], [srtp], [srtp_init], [srtp/srtp.h])
 
 if test "$PBX_SRTP" = "1";

diff --git a/include/asterisk/autoconfig.h.in b/include/asterisk/autoconfig.h.in
index 4efff1f21b0d7d8322e008dd9d75cbde89927acd..542f5d2a00a73c053f0151b24b18ddb037ac10ab 100644 (file)
--- a/include/asterisk/autoconfig.h.in
+++ b/include/asterisk/autoconfig.h.in
@@ -548,6 +548,9 @@
 /* Define to 1 if CRYPTO has the OpenSSL Elliptic Curve Support feature. */
 #undef HAVE_OPENSSL_EC
 
+/* Define if your system has SSL_CTX_set_ecdh_auto declared. */
+#undef HAVE_OPENSSL_ECDH_AUTO
+
 /* Define to 1 if CRYPTO has the OpenSSL SRTP Extension Support feature. */
 #undef HAVE_OPENSSL_SRTP
 

diff --git a/res/res_rtp_asterisk.c b/res/res_rtp_asterisk.c
index 5d206c1a0201a04b9b6677bd9fdbb96c7e36315c..0c47e1e25231b2e77c31e87518f3ad87460a8475 100644 (file)
--- a/res/res_rtp_asterisk.c
+++ b/res/res_rtp_asterisk.c
@@ -1288,6 +1288,13 @@ static int ast_rtp_dtls_set_configuration(struct ast_rtp_instance *instance, con
 
        SSL_CTX_set_read_ahead(rtp->ssl_ctx, 1);
 
+#ifdef HAVE_OPENSSL_ECDH_AUTO
+       SSL_CTX_set_ecdh_auto(rtp->ssl_ctx, 1);
+#else
+       SSL_CTX_set_tmp_ecdh(rtp->ssl_ctx,
+               EC_KEY_new_by_curve_name(NID_X9_62_prime256v1));
+#endif
+
        rtp->dtls_verify = dtls_cfg->verify;
 
        SSL_CTX_set_verify(rtp->ssl_ctx, (rtp->dtls_verify & AST_RTP_DTLS_VERIFY_FINGERPRINT) || (rtp->dtls_verify & AST_RTP_DTLS_VERIFY_CERTIFICATE) ?