[Asterisk-code-review] res srtp: Enable AES-256 and AES-GCM. (asterisk[14])

Joshua Colp asteriskteam at digium.com
Fri Jul 22 11:50:59 CDT 2016


Joshua Colp has submitted this change and it was merged.

Change subject: res_srtp: Enable AES-256 and AES-GCM.
......................................................................


res_srtp: Enable AES-256 and AES-GCM.

ASTERISK-26190 #close

Change-Id: I11326d80edd656524a51a19450e586c583aa0a0b
---
M channels/chan_sip.c
M configure
M configure.ac
M include/asterisk/autoconfig.h.in
M include/asterisk/res_srtp.h
M include/asterisk/sdp_srtp.h
M main/sdp_srtp.c
M res/res_pjsip_sdp_rtp.c
M res/res_srtp.c
9 files changed, 806 insertions(+), 114 deletions(-)

Approvals:
  Mark Michelson: Looks good to me, but someone else must approve
  Joshua Colp: Looks good to me, approved; Verified



diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index b2522b6..5f62ff5 100644
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -284,6 +284,7 @@
 #include "asterisk/features_config.h"
 #include "asterisk/http_websocket.h"
 #include "asterisk/format_cache.h"
+#include "asterisk/linkedlists.h"	/* for AST_LIST_NEXT */
 
 /*** DOCUMENTATION
 	<application name="SIPDtmfMode" language="en_US">
@@ -13220,21 +13221,34 @@
 
 static char *crypto_get_attrib(struct ast_sdp_srtp *srtp, int dtls_enabled, int default_taglen_32)
 {
+	struct ast_sdp_srtp *tmp = srtp;
 	char *a_crypto;
-	const char *orig_crypto;
 
-	if (!srtp || dtls_enabled) {
+	if (!tmp || dtls_enabled) {
 		return NULL;
 	}
 
-	orig_crypto = ast_sdp_srtp_get_attrib(srtp, dtls_enabled, default_taglen_32);
-	if (ast_strlen_zero(orig_crypto)) {
+	a_crypto = ast_strdup("");
+	if (!a_crypto) {
 		return NULL;
 	}
 
-	if (ast_asprintf(&a_crypto, "a=crypto:%s\r\n", orig_crypto) == -1) {
-		return NULL;
-	}
+	do {
+		char *copy = a_crypto;
+		const char *orig_crypto = ast_sdp_srtp_get_attrib(tmp, dtls_enabled, default_taglen_32);
+
+		if (ast_strlen_zero(orig_crypto)) {
+			ast_free(copy);
+			return NULL;
+		}
+		if (ast_asprintf(&a_crypto, "%sa=crypto:%s\r\n", copy, orig_crypto) == -1) {
+			ast_free(copy);
+			return NULL;
+		}
+
+		ast_free(copy);
+	} while ((tmp = AST_LIST_NEXT(tmp, sdp_srtp_list)));
+
 	return a_crypto;
 }
 
diff --git a/configure b/configure
index 6d3faf2..936538e 100755
--- a/configure
+++ b/configure
@@ -778,6 +778,18 @@
 SRTP_SHUTDOWN_DIR
 SRTP_SHUTDOWN_INCLUDE
 SRTP_SHUTDOWN_LIB
+PBX_SRTP_GCM
+SRTP_GCM_DIR
+SRTP_GCM_INCLUDE
+SRTP_GCM_LIB
+PBX_SRTP_192
+SRTP_192_DIR
+SRTP_192_INCLUDE
+SRTP_192_LIB
+PBX_SRTP_256
+SRTP_256_DIR
+SRTP_256_INCLUDE
+SRTP_256_LIB
 PBX_SRTP
 SRTP_DIR
 SRTP_INCLUDE
@@ -11736,6 +11748,42 @@
 
 fi
 
+
+
+
+
+
+
+
+SRTP_256_DESCRIP="SRTP Library AES-256 (ICM)"
+SRTP_256_OPTION=srtp
+SRTP_256_DIR=${SRTP_DIR}
+
+PBX_SRTP_256=0
+
+
+
+
+
+
+
+SRTP_192_DESCRIP="SRTP Library AES-192 (ICM)"
+SRTP_192_OPTION=srtp
+SRTP_192_DIR=${SRTP_DIR}
+
+PBX_SRTP_192=0
+
+
+
+
+
+
+
+SRTP_GCM_DESCRIP="SRTP Library AES-128 (GCM) and AES-256 (GCM)"
+SRTP_GCM_OPTION=srtp
+SRTP_GCM_DIR=${SRTP_DIR}
+
+PBX_SRTP_GCM=0
 
 
 
@@ -32115,6 +32163,322 @@
     CFLAGS="${saved_cflags}"
 fi
 
+if test "$PBX_SRTP" = "1";
+then
+
+if test "x${PBX_SRTP_256}" != "x1" -a "${USE_SRTP_256}" != "no"; then
+   pbxlibdir=""
+   # if --with-SRTP_256=DIR has been specified, use it.
+   if test "x${SRTP_256_DIR}" != "x"; then
+      if test -d ${SRTP_256_DIR}/lib; then
+         pbxlibdir="-L${SRTP_256_DIR}/lib"
+      else
+         pbxlibdir="-L${SRTP_256_DIR}"
+      fi
+   fi
+   pbxfuncname="crypto_policy_set_aes_cm_256_hmac_sha1_80"
+   if test "x${pbxfuncname}" = "x" ; then   # empty lib, assume only headers
+      AST_SRTP_256_FOUND=yes
+   else
+      ast_ext_lib_check_save_CFLAGS="${CFLAGS}"
+      CFLAGS="${CFLAGS} "
+      as_ac_Lib=`$as_echo "ac_cv_lib_srtp_${pbxfuncname}" | $as_tr_sh`
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for ${pbxfuncname} in -lsrtp" >&5
+$as_echo_n "checking for ${pbxfuncname} in -lsrtp... " >&6; }
+if eval \${$as_ac_Lib+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_check_lib_save_LIBS=$LIBS
+LIBS="-lsrtp ${pbxlibdir}  $LIBS"
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char ${pbxfuncname} ();
+int
+main ()
+{
+return ${pbxfuncname} ();
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  eval "$as_ac_Lib=yes"
+else
+  eval "$as_ac_Lib=no"
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+eval ac_res=\$$as_ac_Lib
+	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+$as_echo "$ac_res" >&6; }
+if eval test \"x\$"$as_ac_Lib"\" = x"yes"; then :
+  AST_SRTP_256_FOUND=yes
+else
+  AST_SRTP_256_FOUND=no
+fi
+
+      CFLAGS="${ast_ext_lib_check_save_CFLAGS}"
+   fi
+
+   # now check for the header.
+   if test "${AST_SRTP_256_FOUND}" = "yes"; then
+      SRTP_256_LIB="${pbxlibdir} -lsrtp "
+      # if --with-SRTP_256=DIR has been specified, use it.
+      if test "x${SRTP_256_DIR}" != "x"; then
+         SRTP_256_INCLUDE="-I${SRTP_256_DIR}/include"
+      fi
+      SRTP_256_INCLUDE="${SRTP_256_INCLUDE} "
+      if test "x" = "x" ; then	# no header, assume found
+         SRTP_256_HEADER_FOUND="1"
+      else				# check for the header
+         ast_ext_lib_check_saved_CPPFLAGS="${CPPFLAGS}"
+         CPPFLAGS="${CPPFLAGS} ${SRTP_256_INCLUDE}"
+         ac_fn_c_check_header_mongrel "$LINENO" "" "ac_cv_header_" "$ac_includes_default"
+if test "x$ac_cv_header_" = xyes; then :
+  SRTP_256_HEADER_FOUND=1
+else
+  SRTP_256_HEADER_FOUND=0
+fi
+
+
+         CPPFLAGS="${ast_ext_lib_check_saved_CPPFLAGS}"
+      fi
+      if test "x${SRTP_256_HEADER_FOUND}" = "x0" ; then
+         SRTP_256_LIB=""
+         SRTP_256_INCLUDE=""
+      else
+         if test "x${pbxfuncname}" = "x" ; then		# only checking headers -> no library
+            SRTP_256_LIB=""
+         fi
+         PBX_SRTP_256=1
+         cat >>confdefs.h <<_ACEOF
+#define HAVE_SRTP_256 1
+_ACEOF
+
+      fi
+   fi
+fi
+
+
+
+if test "x${PBX_SRTP_192}" != "x1" -a "${USE_SRTP_192}" != "no"; then
+   pbxlibdir=""
+   # if --with-SRTP_192=DIR has been specified, use it.
+   if test "x${SRTP_192_DIR}" != "x"; then
+      if test -d ${SRTP_192_DIR}/lib; then
+         pbxlibdir="-L${SRTP_192_DIR}/lib"
+      else
+         pbxlibdir="-L${SRTP_192_DIR}"
+      fi
+   fi
+   pbxfuncname="crypto_policy_set_aes_cm_192_hmac_sha1_80"
+   if test "x${pbxfuncname}" = "x" ; then   # empty lib, assume only headers
+      AST_SRTP_192_FOUND=yes
+   else
+      ast_ext_lib_check_save_CFLAGS="${CFLAGS}"
+      CFLAGS="${CFLAGS} "
+      as_ac_Lib=`$as_echo "ac_cv_lib_srtp_${pbxfuncname}" | $as_tr_sh`
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for ${pbxfuncname} in -lsrtp" >&5
+$as_echo_n "checking for ${pbxfuncname} in -lsrtp... " >&6; }
+if eval \${$as_ac_Lib+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_check_lib_save_LIBS=$LIBS
+LIBS="-lsrtp ${pbxlibdir}  $LIBS"
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char ${pbxfuncname} ();
+int
+main ()
+{
+return ${pbxfuncname} ();
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  eval "$as_ac_Lib=yes"
+else
+  eval "$as_ac_Lib=no"
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+eval ac_res=\$$as_ac_Lib
+	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+$as_echo "$ac_res" >&6; }
+if eval test \"x\$"$as_ac_Lib"\" = x"yes"; then :
+  AST_SRTP_192_FOUND=yes
+else
+  AST_SRTP_192_FOUND=no
+fi
+
+      CFLAGS="${ast_ext_lib_check_save_CFLAGS}"
+   fi
+
+   # now check for the header.
+   if test "${AST_SRTP_192_FOUND}" = "yes"; then
+      SRTP_192_LIB="${pbxlibdir} -lsrtp "
+      # if --with-SRTP_192=DIR has been specified, use it.
+      if test "x${SRTP_192_DIR}" != "x"; then
+         SRTP_192_INCLUDE="-I${SRTP_192_DIR}/include"
+      fi
+      SRTP_192_INCLUDE="${SRTP_192_INCLUDE} "
+      if test "x" = "x" ; then	# no header, assume found
+         SRTP_192_HEADER_FOUND="1"
+      else				# check for the header
+         ast_ext_lib_check_saved_CPPFLAGS="${CPPFLAGS}"
+         CPPFLAGS="${CPPFLAGS} ${SRTP_192_INCLUDE}"
+         ac_fn_c_check_header_mongrel "$LINENO" "" "ac_cv_header_" "$ac_includes_default"
+if test "x$ac_cv_header_" = xyes; then :
+  SRTP_192_HEADER_FOUND=1
+else
+  SRTP_192_HEADER_FOUND=0
+fi
+
+
+         CPPFLAGS="${ast_ext_lib_check_saved_CPPFLAGS}"
+      fi
+      if test "x${SRTP_192_HEADER_FOUND}" = "x0" ; then
+         SRTP_192_LIB=""
+         SRTP_192_INCLUDE=""
+      else
+         if test "x${pbxfuncname}" = "x" ; then		# only checking headers -> no library
+            SRTP_192_LIB=""
+         fi
+         PBX_SRTP_192=1
+         cat >>confdefs.h <<_ACEOF
+#define HAVE_SRTP_192 1
+_ACEOF
+
+      fi
+   fi
+fi
+
+
+
+if test "x${PBX_SRTP_GCM}" != "x1" -a "${USE_SRTP_GCM}" != "no"; then
+   pbxlibdir=""
+   # if --with-SRTP_GCM=DIR has been specified, use it.
+   if test "x${SRTP_GCM_DIR}" != "x"; then
+      if test -d ${SRTP_GCM_DIR}/lib; then
+         pbxlibdir="-L${SRTP_GCM_DIR}/lib"
+      else
+         pbxlibdir="-L${SRTP_GCM_DIR}"
+      fi
+   fi
+   pbxfuncname="aes_gcm_128_openssl"
+   if test "x${pbxfuncname}" = "x" ; then   # empty lib, assume only headers
+      AST_SRTP_GCM_FOUND=yes
+   else
+      ast_ext_lib_check_save_CFLAGS="${CFLAGS}"
+      CFLAGS="${CFLAGS} "
+      as_ac_Lib=`$as_echo "ac_cv_lib_srtp_${pbxfuncname}" | $as_tr_sh`
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for ${pbxfuncname} in -lsrtp" >&5
+$as_echo_n "checking for ${pbxfuncname} in -lsrtp... " >&6; }
+if eval \${$as_ac_Lib+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_check_lib_save_LIBS=$LIBS
+LIBS="-lsrtp ${pbxlibdir}  $LIBS"
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char ${pbxfuncname} ();
+int
+main ()
+{
+return ${pbxfuncname} ();
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  eval "$as_ac_Lib=yes"
+else
+  eval "$as_ac_Lib=no"
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+eval ac_res=\$$as_ac_Lib
+	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+$as_echo "$ac_res" >&6; }
+if eval test \"x\$"$as_ac_Lib"\" = x"yes"; then :
+  AST_SRTP_GCM_FOUND=yes
+else
+  AST_SRTP_GCM_FOUND=no
+fi
+
+      CFLAGS="${ast_ext_lib_check_save_CFLAGS}"
+   fi
+
+   # now check for the header.
+   if test "${AST_SRTP_GCM_FOUND}" = "yes"; then
+      SRTP_GCM_LIB="${pbxlibdir} -lsrtp "
+      # if --with-SRTP_GCM=DIR has been specified, use it.
+      if test "x${SRTP_GCM_DIR}" != "x"; then
+         SRTP_GCM_INCLUDE="-I${SRTP_GCM_DIR}/include"
+      fi
+      SRTP_GCM_INCLUDE="${SRTP_GCM_INCLUDE} "
+      if test "x" = "x" ; then	# no header, assume found
+         SRTP_GCM_HEADER_FOUND="1"
+      else				# check for the header
+         ast_ext_lib_check_saved_CPPFLAGS="${CPPFLAGS}"
+         CPPFLAGS="${CPPFLAGS} ${SRTP_GCM_INCLUDE}"
+         ac_fn_c_check_header_mongrel "$LINENO" "" "ac_cv_header_" "$ac_includes_default"
+if test "x$ac_cv_header_" = xyes; then :
+  SRTP_GCM_HEADER_FOUND=1
+else
+  SRTP_GCM_HEADER_FOUND=0
+fi
+
+
+         CPPFLAGS="${ast_ext_lib_check_saved_CPPFLAGS}"
+      fi
+      if test "x${SRTP_GCM_HEADER_FOUND}" = "x0" ; then
+         SRTP_GCM_LIB=""
+         SRTP_GCM_INCLUDE=""
+      else
+         if test "x${pbxfuncname}" = "x" ; then		# only checking headers -> no library
+            SRTP_GCM_LIB=""
+         fi
+         PBX_SRTP_GCM=1
+         cat >>confdefs.h <<_ACEOF
+#define HAVE_SRTP_GCM 1
+_ACEOF
+
+      fi
+   fi
+fi
+
+
+fi
+
 
 if test "x${PBX_SRTP_SHUTDOWN}" != "x1" -a "${USE_SRTP_SHUTDOWN}" != "no"; then
    pbxlibdir=""
diff --git a/configure.ac b/configure.ac
index dedfd8a..964232e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -529,6 +529,9 @@
 AST_EXT_LIB_SETUP([SQLITE], [SQLite], [sqlite])
 AST_EXT_LIB_SETUP([SQLITE3], [SQLite], [sqlite3])
 AST_EXT_LIB_SETUP([SRTP], [Secure RTP], [srtp])
+AST_EXT_LIB_SETUP_OPTIONAL([SRTP_256], [SRTP Library AES-256 (ICM)], [SRTP], [srtp])
+AST_EXT_LIB_SETUP_OPTIONAL([SRTP_192], [SRTP Library AES-192 (ICM)], [SRTP], [srtp])
+AST_EXT_LIB_SETUP_OPTIONAL([SRTP_GCM], [SRTP Library AES-128 (GCM) and AES-256 (GCM)], [SRTP], [srtp])
 AST_EXT_LIB_SETUP_OPTIONAL([SRTP_SHUTDOWN], [SRTP Library Shutdown Function], [SRTP], [srtp])
 AST_EXT_LIB_SETUP([OPENSSL], [OpenSSL Secure Sockets Layer], [ssl])
 AST_EXT_LIB_SETUP_OPTIONAL([RT], [Realtime functions], [rt])
@@ -2450,6 +2453,13 @@
     CFLAGS="${saved_cflags}"
 fi
 
+if test "$PBX_SRTP" = "1";
+then
+	AST_EXT_LIB_CHECK([SRTP_256], [srtp], [crypto_policy_set_aes_cm_256_hmac_sha1_80])
+	AST_EXT_LIB_CHECK([SRTP_192], [srtp], [crypto_policy_set_aes_cm_192_hmac_sha1_80])
+	AST_EXT_LIB_CHECK([SRTP_GCM], [srtp], [aes_gcm_128_openssl])
+fi
+
 AST_EXT_LIB_CHECK([SRTP_SHUTDOWN], [srtp], [srtp_shutdown], [srtp/srtp.h])
 
 for ver in 2.0 2.2 2.4 2.6; do
diff --git a/include/asterisk/autoconfig.h.in b/include/asterisk/autoconfig.h.in
index 51f0f14..8fd4a32 100644
--- a/include/asterisk/autoconfig.h.in
+++ b/include/asterisk/autoconfig.h.in
@@ -838,6 +838,16 @@
 /* Define to 1 if you have the Secure RTP library. */
 #undef HAVE_SRTP
 
+/* Define to 1 if SRTP has the SRTP Library AES-192 (ICM) feature. */
+#undef HAVE_SRTP_192
+
+/* Define to 1 if SRTP has the SRTP Library AES-256 (ICM) feature. */
+#undef HAVE_SRTP_256
+
+/* Define to 1 if SRTP has the SRTP Library AES-128 (GCM) and AES-256 (GCM)
+   feature. */
+#undef HAVE_SRTP_GCM
+
 /* Define to 1 if SRTP has the SRTP Library Shutdown Function feature. */
 #undef HAVE_SRTP_SHUTDOWN
 
diff --git a/include/asterisk/res_srtp.h b/include/asterisk/res_srtp.h
index c7fdc40..741d4f9 100644
--- a/include/asterisk/res_srtp.h
+++ b/include/asterisk/res_srtp.h
@@ -21,6 +21,8 @@
 #ifndef _ASTERISK_RES_SRTP_H
 #define _ASTERISK_RES_SRTP_H
 
+#include "asterisk.h"                   /* for size_t */
+
 struct ast_srtp;
 struct ast_srtp_policy;
 struct ast_rtp_instance;
@@ -52,9 +54,17 @@
 
 /* Crypto suites */
 enum ast_srtp_suite {
+	/* https://www.iana.org/assignments/srtp-protection/srtp-protection.xhtml */
 	AST_AES_CM_128_HMAC_SHA1_80 = 1,
-	AST_AES_CM_128_HMAC_SHA1_32 = 2,
-	AST_F8_128_HMAC_SHA1_80     = 3
+	AST_AES_CM_128_HMAC_SHA1_32,
+	AST_AES_CM_256_HMAC_SHA1_80,
+	AST_AES_CM_256_HMAC_SHA1_32,
+	AST_AES_GCM_128             = 7,
+	AST_AES_GCM_256,
+	AST_AES_GCM_128_8,
+	AST_AES_GCM_256_8,
+	AST_AES_CM_192_HMAC_SHA1_80,
+	AST_AES_CM_192_HMAC_SHA1_32,
 };
 
 struct ast_srtp_policy_res {
diff --git a/include/asterisk/sdp_srtp.h b/include/asterisk/sdp_srtp.h
index 772c3c3..5d8f0e7 100644
--- a/include/asterisk/sdp_srtp.h
+++ b/include/asterisk/sdp_srtp.h
@@ -20,8 +20,7 @@
  *
  * \brief SRTP and SDP Security descriptions
  *
- * Specified in RFC 4568
- * Specified in RFC 3711
+ * Specified in RFC 3711, 6188, 7714, and 4568
  *
  * \author Mikael Magnusson <mikma at users.sourceforge.net>
  */
@@ -29,7 +28,8 @@
 #ifndef _SDP_SRTP_H
 #define _SDP_SRTP_H
 
-#include <asterisk/rtp_engine.h>
+#include "asterisk/linkedlists.h"       /* for AST_LIST_ENTRY */
+#include "asterisk/rtp_engine.h"        /* for ast_rtp_instance */
 
 struct ast_sdp_crypto;
 
@@ -37,12 +37,18 @@
 struct ast_sdp_srtp {
 	unsigned int flags;
 	struct ast_sdp_crypto *crypto;
+	AST_LIST_ENTRY(ast_sdp_srtp) sdp_srtp_list;
 };
 
 /* SRTP flags */
-#define AST_SRTP_CRYPTO_OFFER_OK	(1 << 1)
-#define AST_SRTP_CRYPTO_TAG_32		(1 << 2)
-#define AST_SRTP_CRYPTO_TAG_80		(1 << 3)
+#define AST_SRTP_CRYPTO_OFFER_OK (1 << 1)
+#define AST_SRTP_CRYPTO_TAG_32   (1 << 2)
+#define AST_SRTP_CRYPTO_TAG_80   (1 << 3)
+#define AST_SRTP_CRYPTO_TAG_16   (1 << 4)
+#define AST_SRTP_CRYPTO_TAG_8    (1 << 5)
+#define AST_SRTP_CRYPTO_AES_192  (1 << 6)
+#define AST_SRTP_CRYPTO_AES_256  (1 << 7)
+#define AST_SRTP_CRYPTO_OLD_NAME (1 << 8)
 
 /*!
  * \brief allocate a ast_sdp_srtp structure
diff --git a/main/sdp_srtp.c b/main/sdp_srtp.c
index c92387b..a55aedf 100644
--- a/main/sdp_srtp.c
+++ b/main/sdp_srtp.c
@@ -20,8 +20,7 @@
  *
  * \brief SRTP and SDP Security descriptions
  *
- * Specified in RFC 3711
- * Specified in RFC 4568
+ * Specified in RFC 3711, 6188, 7714, and 4568
  *
  * \author Mikael Magnusson <mikma at users.sourceforge.net>
  */
@@ -34,15 +33,15 @@
 
 ASTERISK_REGISTER_FILE()
 
-#include <math.h>
-#include "asterisk/options.h"
-#include "asterisk/utils.h"
-#include "asterisk/sdp_srtp.h"
+#include <math.h>                       /* for pow */
+#include <srtp/srtp.h>                  /* for SRTP_MAX_KEY_LEN, etc */
 
-#define SRTP_MASTER_LEN 30
-#define SRTP_MASTERKEY_LEN 16
-#define SRTP_MASTERSALT_LEN ((SRTP_MASTER_LEN) - (SRTP_MASTERKEY_LEN))
-#define SRTP_MASTER_LEN64 (((SRTP_MASTER_LEN) * 8 + 5) / 6 + 1)
+#include "asterisk/linkedlists.h"       /* for AST_LIST_NEXT, etc */
+#include "asterisk/logger.h"            /* for ast_log, LOG_ERROR, etc */
+#include "asterisk/rtp_engine.h"        /* for ast_rtp_engine_dtls, etc */
+#include "asterisk/sdp_srtp.h"          /* for ast_sdp_srtp, etc */
+#include "asterisk/strings.h"           /* for ast_strlen_zero */
+#include "asterisk/utils.h"             /* for ast_set_flag, ast_test_flag, etc */
 
 extern struct ast_srtp_res *res_srtp;
 extern struct ast_srtp_policy_res *res_srtp_policy;
@@ -59,22 +58,31 @@
 
 void ast_sdp_srtp_destroy(struct ast_sdp_srtp *srtp)
 {
-	if (srtp->crypto) {
-		ast_sdp_crypto_destroy(srtp->crypto);
+	struct ast_sdp_srtp *next;
+
+	for (next = AST_LIST_NEXT(srtp, sdp_srtp_list);
+	     srtp;
+	     srtp = next, next = srtp ? AST_LIST_NEXT(srtp, sdp_srtp_list) : NULL) {
+		if (srtp->crypto) {
+			ast_sdp_crypto_destroy(srtp->crypto);
+		}
+		srtp->crypto = NULL;
+		ast_free(srtp);
 	}
-	srtp->crypto = NULL;
-	ast_free(srtp);
 }
 
 struct ast_sdp_crypto {
 	char *a_crypto;
-	unsigned char local_key[SRTP_MASTER_LEN];
+	unsigned char local_key[SRTP_MAX_KEY_LEN];
 	int tag;
-	char local_key64[SRTP_MASTER_LEN64];
-	unsigned char remote_key[SRTP_MASTER_LEN];
+	char local_key64[((SRTP_MAX_KEY_LEN) * 8 + 5) / 6 + 1];
+	unsigned char remote_key[SRTP_MAX_KEY_LEN];
+	int key_len;
 };
 
-static int set_crypto_policy(struct ast_srtp_policy *policy, int suite_val, const unsigned char *master_key, unsigned long ssrc, int inbound);
+static struct ast_sdp_crypto *sdp_crypto_alloc(const int key_len);
+static struct ast_sdp_crypto *crypto_init_keys(struct ast_sdp_crypto *p, const int key_len);
+static int set_crypto_policy(struct ast_srtp_policy *policy, int suite_val, const unsigned char *master_key, int key_len, unsigned long ssrc, int inbound);
 
 void ast_sdp_crypto_destroy(struct ast_sdp_crypto *crypto)
 {
@@ -83,11 +91,36 @@
 	ast_free(crypto);
 }
 
-struct ast_sdp_crypto *ast_sdp_crypto_alloc(void)
+static struct ast_sdp_crypto *crypto_init_keys(struct ast_sdp_crypto *p, const int key_len)
 {
-	struct ast_sdp_crypto *p;
-	int key_len;
-	unsigned char remote_key[SRTP_MASTER_LEN];
+	unsigned char remote_key[key_len];
+
+	if (res_srtp->get_random(p->local_key, key_len) < 0) {
+		return NULL;
+	}
+
+	ast_base64encode(p->local_key64, p->local_key, key_len, sizeof(p->local_key64));
+
+	p->key_len = ast_base64decode(remote_key, p->local_key64, sizeof(remote_key));
+
+	if (p->key_len != key_len) {
+		ast_log(LOG_ERROR, "base64 encode/decode bad len %d != %d\n", p->key_len, key_len);
+		return NULL;
+	}
+
+	if (memcmp(remote_key, p->local_key, p->key_len)) {
+		ast_log(LOG_ERROR, "base64 encode/decode bad key\n");
+		return NULL;
+	}
+
+	ast_debug(1 , "local_key64 %s len %zu\n", p->local_key64, strlen(p->local_key64));
+
+	return p;
+}
+
+static struct ast_sdp_crypto *sdp_crypto_alloc(const int key_len)
+{
+	struct ast_sdp_crypto *p, *result;
 
 	if (!ast_rtp_engine_srtp_is_registered()) {
 		return NULL;
@@ -98,42 +131,27 @@
 	}
 	p->tag = 1;
 
-	if (res_srtp->get_random(p->local_key, sizeof(p->local_key)) < 0) {
+	/* default is a key which uses AST_AES_CM_128_HMAC_SHA1_xx */
+	result = crypto_init_keys(p, key_len);
+	if (!result) {
 		ast_sdp_crypto_destroy(p);
-		return NULL;
 	}
 
-	ast_base64encode(p->local_key64, p->local_key, SRTP_MASTER_LEN, sizeof(p->local_key64));
-
-	key_len = ast_base64decode(remote_key, p->local_key64, sizeof(remote_key));
-
-	if (key_len != SRTP_MASTER_LEN) {
-		ast_log(LOG_ERROR, "base64 encode/decode bad len %d != %d\n", key_len, SRTP_MASTER_LEN);
-		ast_sdp_crypto_destroy(p);
-		return NULL;
-	}
-
-	if (memcmp(remote_key, p->local_key, SRTP_MASTER_LEN)) {
-		ast_log(LOG_ERROR, "base64 encode/decode bad key\n");
-		ast_sdp_crypto_destroy(p);
-		return NULL;
-	}
-
-	ast_debug(1 , "local_key64 %s len %zu\n", p->local_key64, strlen(p->local_key64));
-
-	return p;
+	return result;
 }
 
-static int set_crypto_policy(struct ast_srtp_policy *policy, int suite_val, const unsigned char *master_key, unsigned long ssrc, int inbound)
+struct ast_sdp_crypto *ast_sdp_crypto_alloc(void)
 {
-	const unsigned char *master_salt = NULL;
+	return sdp_crypto_alloc(SRTP_MASTER_KEY_LEN);
+}
 
+static int set_crypto_policy(struct ast_srtp_policy *policy, int suite_val, const unsigned char *master_key, int key_len, unsigned long ssrc, int inbound)
+{
 	if (!ast_rtp_engine_srtp_is_registered()) {
 		return -1;
 	}
 
-	master_salt = master_key + SRTP_MASTERKEY_LEN;
-	if (res_srtp_policy->set_master_key(policy, master_key, SRTP_MASTERKEY_LEN, master_salt, SRTP_MASTERSALT_LEN) < 0) {
+	if (res_srtp_policy->set_master_key(policy, master_key, key_len, NULL, 0) < 0) {
 		return -1;
 	}
 
@@ -147,7 +165,7 @@
 	return 0;
 }
 
-static int crypto_activate(struct ast_sdp_crypto *p, int suite_val, unsigned char *remote_key, struct ast_rtp_instance *rtp)
+static int crypto_activate(struct ast_sdp_crypto *p, int suite_val, unsigned char *remote_key, int key_len, struct ast_rtp_instance *rtp)
 {
 	struct ast_srtp_policy *local_policy = NULL;
 	struct ast_srtp_policy *remote_policy = NULL;
@@ -174,11 +192,11 @@
 		goto err;
 	}
 
-	if (set_crypto_policy(local_policy, suite_val, p->local_key, stats.local_ssrc, 0) < 0) {
+	if (set_crypto_policy(local_policy, suite_val, p->local_key, key_len, stats.local_ssrc, 0) < 0) {
 		goto err;
 	}
 
-	if (set_crypto_policy(remote_policy, suite_val, remote_key, 0, 1) < 0) {
+	if (set_crypto_policy(remote_policy, suite_val, remote_key, key_len, 0, 1) < 0) {
 		goto err;
 	}
 
@@ -215,12 +233,15 @@
 	char *lifetime = NULL;       /* Key lifetime (# of RTP packets) */
 	char *mki = NULL;            /* Master Key Index */
 	int found = 0;
-	int key_len = 0;
+	int key_len_from_sdp;
+	int key_len_expected;
+	int tag_from_sdp;
 	int suite_val = 0;
-	unsigned char remote_key[SRTP_MASTER_LEN];
-	int taglen = 0;
+	unsigned char remote_key[SRTP_MAX_KEY_LEN];
+	int taglen;
 	double sdes_lifetime;
-	struct ast_sdp_crypto *crypto = srtp->crypto;
+	struct ast_sdp_crypto *crypto;
+	struct ast_sdp_srtp *tmp;
 
 	if (!ast_rtp_engine_srtp_is_registered()) {
 		return -1;
@@ -239,7 +260,7 @@
 	}
 
 	/* RFC4568 9.1 - tag is 1-9 digits, greater than zero */
-	if (sscanf(tag, "%30d", &crypto->tag) != 1 || crypto->tag <= 0 || crypto->tag > 999999999) {
+	if (sscanf(tag, "%30d", &tag_from_sdp) != 1 || tag_from_sdp <= 0 || tag_from_sdp > 999999999) {
 		ast_log(LOG_WARNING, "Unacceptable a=crypto tag: %s\n", tag);
 		return -1;
 	}
@@ -249,16 +270,107 @@
 		return -1;
 	}
 
+	/* On egress, Asterisk sent several crypto lines in the SIP/SDP offer
+	   The remote party might have choosen another line than the first */
+	for (tmp = srtp; tmp && tmp->crypto && tmp->crypto->tag != tag_from_sdp;) {
+		tmp = AST_LIST_NEXT(tmp, sdp_srtp_list);
+	}
+	if (tmp) { /* tag matched an already created crypto line */
+		unsigned int flags = tmp->flags;
+
+		/* Make that crypto line the head of the list, not by changing the
+		   list structure but by exchanging the content of the list members */
+		crypto = tmp->crypto;
+		tmp->crypto = srtp->crypto;
+		tmp->flags = srtp->flags;
+		srtp->crypto = crypto;
+		srtp->flags = flags;
+	} else {
+		crypto = srtp->crypto;
+		crypto->tag = tag_from_sdp;
+	}
+
 	if (!strcmp(suite, "AES_CM_128_HMAC_SHA1_80")) {
 		suite_val = AST_AES_CM_128_HMAC_SHA1_80;
 		ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_80);
-		taglen = 80;
+		key_len_expected = 30;
 	} else if (!strcmp(suite, "AES_CM_128_HMAC_SHA1_32")) {
 		suite_val = AST_AES_CM_128_HMAC_SHA1_32;
 		ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_32);
-		taglen = 32;
+		key_len_expected = 30;
+#ifdef HAVE_SRTP_192
+	} else if (!strcmp(suite, "AES_192_CM_HMAC_SHA1_80")) {
+		suite_val = AST_AES_CM_192_HMAC_SHA1_80;
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_80);
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_192);
+		key_len_expected = 38;
+	} else if (!strcmp(suite, "AES_192_CM_HMAC_SHA1_32")) {
+		suite_val = AST_AES_CM_192_HMAC_SHA1_32;
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_32);
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_192);
+		key_len_expected = 38;
+	/* RFC used a different name while in draft, some still use that */
+	} else if (!strcmp(suite, "AES_CM_192_HMAC_SHA1_80")) {
+		suite_val = AST_AES_CM_192_HMAC_SHA1_80;
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_80);
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_192);
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_OLD_NAME);
+		key_len_expected = 38;
+	} else if (!strcmp(suite, "AES_CM_192_HMAC_SHA1_32")) {
+		suite_val = AST_AES_CM_192_HMAC_SHA1_32;
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_32);
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_192);
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_OLD_NAME);
+		key_len_expected = 38;
+#endif
+#ifdef HAVE_SRTP_256
+	} else if (!strcmp(suite, "AES_256_CM_HMAC_SHA1_80")) {
+		suite_val = AST_AES_CM_256_HMAC_SHA1_80;
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_80);
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_256);
+		key_len_expected = 46;
+	} else if (!strcmp(suite, "AES_256_CM_HMAC_SHA1_32")) {
+		suite_val = AST_AES_CM_256_HMAC_SHA1_32;
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_32);
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_256);
+		key_len_expected = 46;
+	/* RFC used a different name while in draft, some still use that */
+	} else if (!strcmp(suite, "AES_CM_256_HMAC_SHA1_80")) {
+		suite_val = AST_AES_CM_256_HMAC_SHA1_80;
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_80);
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_256);
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_OLD_NAME);
+		key_len_expected = 46;
+	} else if (!strcmp(suite, "AES_CM_256_HMAC_SHA1_32")) {
+		suite_val = AST_AES_CM_256_HMAC_SHA1_32;
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_32);
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_256);
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_OLD_NAME);
+		key_len_expected = 46;
+#endif
+#ifdef HAVE_SRTP_GCM
+	} else if (!strcmp(suite, "AEAD_AES_128_GCM")) {
+		suite_val = AST_AES_GCM_128;
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_16);
+		key_len_expected = AES_128_GCM_KEYSIZE_WSALT;
+	} else if (!strcmp(suite, "AEAD_AES_256_GCM")) {
+		suite_val = AST_AES_GCM_256;
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_16);
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_256);
+		key_len_expected = AES_256_GCM_KEYSIZE_WSALT;
+	/* RFC contained a (too) short auth tag for RTP media, some still use that */
+	} else if (!strcmp(suite, "AEAD_AES_128_GCM_8")) {
+		suite_val = AST_AES_GCM_128_8;
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_8);
+		key_len_expected = AES_128_GCM_KEYSIZE_WSALT;
+	} else if (!strcmp(suite, "AEAD_AES_256_GCM_8")) {
+		suite_val = AST_AES_GCM_256_8;
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_TAG_8);
+		ast_set_flag(srtp, AST_SRTP_CRYPTO_AES_256);
+		key_len_expected = AES_256_GCM_KEYSIZE_WSALT;
+#endif
 	} else {
-		ast_log(LOG_WARNING, "Unsupported crypto suite: %s\n", suite);
+		ast_verb(1, "Unsupported crypto suite: %s\n", suite);
 		return -1;
 	}
 
@@ -341,22 +453,54 @@
 		return -1;
 	}
 
-	key_len = ast_base64decode(remote_key, key_salt, sizeof(remote_key));
-	if (key_len != SRTP_MASTER_LEN) {
-		ast_log(LOG_WARNING, "SRTP descriptions key length '%d' != master length '%d'\n",
-			key_len, SRTP_MASTER_LEN);
+	key_len_from_sdp = ast_base64decode(remote_key, key_salt, sizeof(remote_key));
+	if (key_len_from_sdp != key_len_expected) {
+		ast_log(LOG_WARNING, "SRTP descriptions key length is '%d', not '%d'\n",
+			key_len_from_sdp, key_len_expected);
 		return -1;
 	}
 
-	if (!memcmp(crypto->remote_key, remote_key, sizeof(crypto->remote_key))) {
+	/* on default, the key is 30 (AES-128); throw that away (only) when the suite changed actually */
+	/* ingress: optional, but saves one expensive call to get_random(.) */
+	/*  egress: required, because the local key was communicated before the remote key is processed */
+	if (crypto->key_len != key_len_from_sdp) {
+		if (!crypto_init_keys(crypto, key_len_from_sdp)) {
+			return -1;
+		}
+	} else if (!memcmp(crypto->remote_key, remote_key, key_len_from_sdp)) {
 		ast_debug(1, "SRTP remote key unchanged; maintaining current policy\n");
 		ast_set_flag(srtp, AST_SRTP_CRYPTO_OFFER_OK);
 		return 0;
 	}
-	memcpy(crypto->remote_key, remote_key, sizeof(crypto->remote_key));
 
-	if (crypto_activate(crypto, suite_val, remote_key, rtp) < 0) {
+	if (key_len_from_sdp > sizeof(crypto->remote_key)) {
+		ast_log(LOG_ERROR,
+			"SRTP key buffer is %zu although it must be at least %d bytes\n",
+			sizeof(crypto->remote_key), key_len_from_sdp);
 		return -1;
+	}
+	memcpy(crypto->remote_key, remote_key, key_len_from_sdp);
+
+	if (crypto_activate(crypto, suite_val, remote_key, key_len_from_sdp, rtp) < 0) {
+		return -1;
+	}
+
+	if (ast_test_flag(srtp, AST_SRTP_CRYPTO_TAG_32)) {
+		taglen = 32;
+	} else if (ast_test_flag(srtp, AST_SRTP_CRYPTO_TAG_16)) {
+		taglen = 16;
+	} else if (ast_test_flag(srtp, AST_SRTP_CRYPTO_TAG_8)) {
+		taglen = 8;
+	} else {
+		taglen = 80;
+	}
+	if (ast_test_flag(srtp, AST_SRTP_CRYPTO_AES_256)) {
+		taglen |= 0x0200;
+	} else if (ast_test_flag(srtp, AST_SRTP_CRYPTO_AES_192)) {
+		taglen |= 0x0100;
+	}
+	if (ast_test_flag(srtp, AST_SRTP_CRYPTO_OLD_NAME)) {
+		taglen |= 0x0080;
 	}
 
 	/* Finally, rebuild the crypto line */
@@ -375,10 +519,30 @@
 		ast_free(p->a_crypto);
 	}
 
-	if (ast_asprintf(&p->a_crypto, "%d AES_CM_128_HMAC_SHA1_%i inline:%s",
-			 p->tag, taglen, p->local_key64) == -1) {
-			ast_log(LOG_ERROR, "Could not allocate memory for crypto line\n");
-		return -1;
+	if ((taglen & 0x007f) == 8) {
+		if (ast_asprintf(&p->a_crypto, "%d AEAD_AES_%d_GCM_%d inline:%s",
+				 p->tag, 128 + ((taglen & 0x0300) >> 2), taglen & 0x007f, p->local_key64) == -1) {
+				 ast_log(LOG_ERROR, "Could not allocate memory for crypto line\n");
+			return -1;
+		}
+	} else if ((taglen & 0x007f) == 16) {
+		if (ast_asprintf(&p->a_crypto, "%d AEAD_AES_%d_GCM inline:%s",
+				 p->tag, 128 + ((taglen & 0x0300) >> 2), p->local_key64) == -1) {
+				 ast_log(LOG_ERROR, "Could not allocate memory for crypto line\n");
+			return -1;
+		}
+	} else if ((taglen & 0x0300) && !(taglen & 0x0080)) {
+		if (ast_asprintf(&p->a_crypto, "%d AES_%d_CM_HMAC_SHA1_%d inline:%s",
+				 p->tag, 128 + ((taglen & 0x0300) >> 2), taglen & 0x007f, p->local_key64) == -1) {
+				 ast_log(LOG_ERROR, "Could not allocate memory for crypto line\n");
+			return -1;
+		}
+	} else {
+		if (ast_asprintf(&p->a_crypto, "%d AES_CM_%d_HMAC_SHA1_%d inline:%s",
+				 p->tag, 128 + ((taglen & 0x0300) >> 2), taglen & 0x007f, p->local_key64) == -1) {
+				 ast_log(LOG_ERROR, "Could not allocate memory for crypto line\n");
+			return -1;
+		}
 	}
 
 	ast_debug(1, "Crypto line: a=crypto:%s\n", p->a_crypto);
@@ -388,7 +552,7 @@
 
 const char *ast_sdp_srtp_get_attrib(struct ast_sdp_srtp *srtp, int dtls_enabled, int default_taglen_32)
 {
-	int taglen = default_taglen_32 ? 32 : 80;
+	int taglen;
 
 	if (!srtp) {
 		return NULL;
@@ -396,7 +560,72 @@
 
 	/* Set encryption properties */
 	if (!srtp->crypto) {
-		srtp->crypto = ast_sdp_crypto_alloc();
+
+		if (AST_LIST_NEXT(srtp, sdp_srtp_list)) {
+			srtp->crypto = ast_sdp_crypto_alloc();
+			ast_log(LOG_ERROR, "SRTP SDP list was not empty\n");
+		} else {
+			const int len = default_taglen_32 ? AST_SRTP_CRYPTO_TAG_32 : AST_SRTP_CRYPTO_TAG_80;
+			const int attr[][3] = {
+			/* This array creates the following list:
+			 * a=crypto:1 AES_CM_128_HMAC_SHA1_ ...
+			 * a=crypto:2 AEAD_AES_128_GCM ...
+			 * a=crypto:3 AES_256_CM_HMAC_SHA1_ ...
+			 * a=crypto:4 AEAD_AES_256_GCM ...
+			 * a=crypto:5 AES_192_CM_HMAC_SHA1_ ...
+			 * something like 'AEAD_AES_192_GCM' is not specified by the RFCs
+			 *
+			 * If you want to prefer another crypto suite or you want to
+			 * exclude a suite, change this array and recompile Asterisk.
+			 * This list cannot be changed from rtp.conf because you should
+			 * know what you are doing. Especially AES-192 and AES-GCM are
+			 * broken in many VoIP clients, see
+			 * https://github.com/cisco/libsrtp/pull/170
+			 * https://github.com/cisco/libsrtp/pull/184
+			 * Furthermore, AES-GCM uses a shorter crypto-suite string which
+			 * causes Nokia phones based on Symbian/S60 to reject the whole
+			 * INVITE with status 500, even if a matching suite was offered.
+			 * AES-256 might just waste your processor cycles, especially if
+			 * your TLS transport is not secured with equivalent grade, see
+			 * https://security.stackexchange.com/q/61361
+			 * Therefore, AES-128 was preferred here.
+			 *
+			 * If you want to enable one of those defines, please, go for
+			 * CFLAGS='-DENABLE_SRTP_AES_GCM' ./configure && sudo make install
+			 */
+				{ len, 0, 30 },
+#if defined(HAVE_SRTP_GCM) && defined(ENABLE_SRTP_AES_GCM)
+				{ AST_SRTP_CRYPTO_TAG_16, 0, AES_128_GCM_KEYSIZE_WSALT },
+#endif
+#if defined(HAVE_SRTP_256) && defined(ENABLE_SRTP_AES_256)
+				{ len, AST_SRTP_CRYPTO_AES_256, 46 },
+#endif
+#if defined(HAVE_SRTP_GCM) && defined(ENABLE_SRTP_AES_GCM) && defined(ENABLE_SRTP_AES_256)
+				{ AST_SRTP_CRYPTO_TAG_16, AST_SRTP_CRYPTO_AES_256, AES_256_GCM_KEYSIZE_WSALT },
+#endif
+#if defined(HAVE_SRTP_192) && defined(ENABLE_SRTP_AES_192)
+				{ len, AST_SRTP_CRYPTO_AES_192, 38 },
+#endif
+			};
+			struct ast_sdp_srtp *tmp = srtp;
+			int i;
+
+			for (i = 0; i < ARRAY_LEN(attr); i++) {
+				if (attr[i][0]) {
+					ast_set_flag(tmp, attr[i][0]);
+				}
+				if (attr[i][1]) {
+					ast_set_flag(tmp, attr[i][1]);
+				}
+				tmp->crypto = sdp_crypto_alloc(attr[i][2]); /* key_len */
+				tmp->crypto->tag = (i + 1); /* tag starts at 1 */
+
+				if (i < ARRAY_LEN(attr) - 1) {
+					AST_LIST_NEXT(tmp, sdp_srtp_list) = ast_sdp_srtp_alloc();
+					tmp = AST_LIST_NEXT(tmp, sdp_srtp_list);
+				}
+			}
+		}
 	}
 
 	if (dtls_enabled) {
@@ -409,6 +638,20 @@
 		taglen = 80;
 	} else if (ast_test_flag(srtp, AST_SRTP_CRYPTO_TAG_32)) {
 		taglen = 32;
+	} else if (ast_test_flag(srtp, AST_SRTP_CRYPTO_TAG_16)) {
+		taglen = 16;
+	} else if (ast_test_flag(srtp, AST_SRTP_CRYPTO_TAG_8)) {
+		taglen = 8;
+	} else {
+		taglen = default_taglen_32 ? 32 : 80;
+	}
+	if (ast_test_flag(srtp, AST_SRTP_CRYPTO_AES_256)) {
+		taglen |= 0x0200;
+	} else if (ast_test_flag(srtp, AST_SRTP_CRYPTO_AES_192)) {
+		taglen |= 0x0100;
+	}
+	if (ast_test_flag(srtp, AST_SRTP_CRYPTO_OLD_NAME)) {
+		taglen |= 0x0080;
 	}
 
 	if (srtp->crypto && (ast_sdp_crypto_build_offer(srtp->crypto, taglen) >= 0)) {
diff --git a/res/res_pjsip_sdp_rtp.c b/res/res_pjsip_sdp_rtp.c
index 048209c..6610ef1 100644
--- a/res/res_pjsip_sdp_rtp.c
+++ b/res/res_pjsip_sdp_rtp.c
@@ -51,6 +51,7 @@
 #include "asterisk/acl.h"
 #include "asterisk/sdp_srtp.h"
 #include "asterisk/dsp.h"
+#include "asterisk/linkedlists.h"       /* for AST_LIST_NEXT */
 
 #include "asterisk/res_pjsip.h"
 #include "asterisk/res_pjsip_session.h"
@@ -938,6 +939,7 @@
 	enum ast_rtp_dtls_hash hash;
 	const char *crypto_attribute;
 	struct ast_rtp_engine_dtls *dtls;
+	struct ast_sdp_srtp *tmp;
 	static const pj_str_t STR_NEW = { "new", 3 };
 	static const pj_str_t STR_EXISTING = { "existing", 8 };
 	static const pj_str_t STR_ACTIVE = { "active", 6 };
@@ -957,16 +959,22 @@
 			}
 		}
 
-		crypto_attribute = ast_sdp_srtp_get_attrib(session_media->srtp,
-			0 /* DTLS running? No */,
-			session->endpoint->media.rtp.srtp_tag_32 /* 32 byte tag length? */);
-		if (!crypto_attribute) {
-			/* No crypto attribute to add, bad news */
-			return -1;
-		}
+		tmp = session_media->srtp;
 
-		attr = pjmedia_sdp_attr_create(pool, "crypto", pj_cstr(&stmp, crypto_attribute));
-		media->attr[media->attr_count++] = attr;
+		do {
+			crypto_attribute = ast_sdp_srtp_get_attrib(tmp,
+				0 /* DTLS running? No */,
+				session->endpoint->media.rtp.srtp_tag_32 /* 32 byte tag length? */);
+			if (!crypto_attribute) {
+				/* No crypto attribute to add, bad news */
+				return -1;
+			}
+
+			attr = pjmedia_sdp_attr_create(pool, "crypto",
+				pj_cstr(&stmp, crypto_attribute));
+			media->attr[media->attr_count++] = attr;
+		} while ((tmp = AST_LIST_NEXT(tmp, sdp_srtp_list)));
+
 		break;
 	case AST_SIP_MEDIA_ENCRYPT_DTLS:
 		if (setup_dtls_srtp(session, session_media)) {
diff --git a/res/res_srtp.c b/res/res_srtp.c
index 0b1fb73..59fda76 100644
--- a/res/res_srtp.c
+++ b/res/res_srtp.c
@@ -35,7 +35,7 @@
 
 /* See https://wiki.asterisk.org/wiki/display/AST/Secure+Calling */
 
-#include "asterisk.h"
+#include "asterisk.h"                   /* for NULL, size_t, memcpy, etc */
 
 ASTERISK_REGISTER_FILE()
 
@@ -46,12 +46,13 @@
 #include <srtp/crypto_kernel.h>
 #endif
 
-#include "asterisk/lock.h"
-#include "asterisk/sched.h"
-#include "asterisk/module.h"
-#include "asterisk/options.h"
-#include "asterisk/rtp_engine.h"
-#include "asterisk/astobj2.h"
+#include "asterisk/astobj2.h"           /* for ao2_t_ref, etc */
+#include "asterisk/frame.h"             /* for AST_FRIENDLY_OFFSET */
+#include "asterisk/logger.h"            /* for ast_log, ast_debug, etc */
+#include "asterisk/module.h"            /* for ast_module_info, etc */
+#include "asterisk/res_srtp.h"          /* for ast_srtp_cb, ast_srtp_suite, etc */
+#include "asterisk/rtp_engine.h"        /* for ast_rtp_engine_register_srtp, etc */
+#include "asterisk/utils.h"             /* for ast_free, ast_calloc */
 
 struct ast_srtp {
 	struct ast_rtp_instance *rtp;
@@ -257,23 +258,49 @@
 {
 	switch (suite) {
 	case AST_AES_CM_128_HMAC_SHA1_80:
-		p->cipher_type = AES_128_ICM;
-		p->cipher_key_len = 30;
-		p->auth_type = HMAC_SHA1;
-		p->auth_key_len = 20;
-		p->auth_tag_len = 10;
-		p->sec_serv = sec_serv_conf_and_auth;
+		crypto_policy_set_aes_cm_128_hmac_sha1_80(p);
 		return 0;
 
 	case AST_AES_CM_128_HMAC_SHA1_32:
-		p->cipher_type = AES_128_ICM;
-		p->cipher_key_len = 30;
-		p->auth_type = HMAC_SHA1;
-		p->auth_key_len = 20;
-		p->auth_tag_len = 4;
-		p->sec_serv = sec_serv_conf_and_auth;
+		crypto_policy_set_aes_cm_128_hmac_sha1_32(p);
 		return 0;
 
+#ifdef HAVE_SRTP_192
+	case AST_AES_CM_192_HMAC_SHA1_80:
+		crypto_policy_set_aes_cm_192_hmac_sha1_80(p);
+		return 0;
+
+	case AST_AES_CM_192_HMAC_SHA1_32:
+		crypto_policy_set_aes_cm_192_hmac_sha1_32(p);
+		return 0;
+#endif
+#ifdef HAVE_SRTP_256
+	case AST_AES_CM_256_HMAC_SHA1_80:
+		crypto_policy_set_aes_cm_256_hmac_sha1_80(p);
+		return 0;
+
+	case AST_AES_CM_256_HMAC_SHA1_32:
+		crypto_policy_set_aes_cm_256_hmac_sha1_32(p);
+		return 0;
+#endif
+#ifdef HAVE_SRTP_GCM
+	case AST_AES_GCM_128:
+		crypto_policy_set_aes_gcm_128_16_auth(p);
+		return 0;
+
+	case AST_AES_GCM_256:
+		crypto_policy_set_aes_gcm_256_16_auth(p);
+		return 0;
+
+	case AST_AES_GCM_128_8:
+		crypto_policy_set_aes_gcm_128_8_auth(p);
+		return 0;
+
+	case AST_AES_GCM_256_8:
+		crypto_policy_set_aes_gcm_256_8_auth(p);
+		return 0;
+#endif
+
 	default:
 		ast_log(LOG_ERROR, "Invalid crypto suite: %u\n", suite);
 		return -1;

-- 
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Gerrit-MessageType: merged
Gerrit-Change-Id: I11326d80edd656524a51a19450e586c583aa0a0b
Gerrit-PatchSet: 1
Gerrit-Project: asterisk
Gerrit-Branch: 14
Gerrit-Owner: Alexander Traud <pabstraud at compuserve.com>
Gerrit-Reviewer: Anonymous Coward #1000019
Gerrit-Reviewer: Joshua Colp <jcolp at digium.com>
Gerrit-Reviewer: Mark Michelson <mmichelson at digium.com>



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