relax sdes key lifetime validation check

fixes #57

daemon/Makefile

@@ -33,6 +33,7 @@ CFLAGS+=	-DMP_PLUGIN_DIR="\"/usr/lib/rtpengine\""
 
 #CFLAGS+=	-DSRTCP_KEY_DERIVATION_RFC_COMPLIANCE
 #CFLAGS+=	-DTERMINATE_SDP_AT_BLANK_LINE
+#CFLAGS+=	-DSTRICT_SDES_KEY_LIFETIME
 
 ifeq ($(DBG),yes)
 CFLAGS+=	-D__DEBUG=1

daemon/sdp.c

@@ -495,7 +495,10 @@ static int parse_attribute_crypto(struct sdp_attribute *output) {
 
 		err = "invalid key lifetime";
 		if (!c->lifetime || c->lifetime > c->crypto_suite->srtp_lifetime
-				|| c->lifetime > c->crypto_suite->srtcp_lifetime)
+#ifdef STRICT_SDES_KEY_LIFETIME
+				|| c->lifetime > c->crypto_suite->srtcp_lifetime
+#endif
+				)
 			goto error;
 	}