[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;
--
To view, visit https://gerrit.asterisk.org/3289
To unsubscribe, visit https://gerrit.asterisk.org/settings
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>
More information about the asterisk-code-review
mailing list