tls_wolfssl: new module TLS stack based on wolfSSL

Initial support. Use OpenSSL-compatiblity layer to achieve
compilation.

src/modules/tls_wolfssl/Makefile

@@ -0,0 +1,81 @@
+#
+# TLS module makefile
+#
+#
+# WARNING: do not run this directly, it should be run by the main Makefile
+
+include ../../Makefile.defs
+auto_gen=
+NAME=tls_wolfssl.so
+
+# set to yes when wanting to link with static libraries
+LIBSSL_STATIC ?= no
+# set to yes when wanting to link with static libraries compiled from source
+LIBSSL_STATIC_SRCLIB ?= no
+# set to the path of the folder with static libraries compiled from source
+LIBSSL_STATIC_SRCPATH ?= /usr/local/src/openssl
+
+ifeq ($(CROSS_COMPILE),)
+WOLFSSL_BUILDER=$(shell \
+	if pkg-config --exists wolfssl; then \
+		echo 'pkg-config wolfssl'; \
+	fi)
+endif
+
+ifneq ($(WOLFSSL_BUILDER),)
+
+ifneq ($(WOLFSSL_STATIC),yes)
+	DEFS += $(shell $(WOLFSSL_BUILDER) --cflags)
+	LIBS += $(shell $(WOLFSSL_BUILDER) --libs)
+
+else # $(WOLFSSL_STATIC),yes)
+
+	DEFS += -DKSR_WOLFSSL_STATIC
+
+ifneq ($(WOLFSSL_STATIC_SRCLIB),yes)
+	## when static libs (*.a) from packages are compiled with -fPIC
+	DEFS += $(shell $(WOLFSSL_BUILDER) --cflags)
+	LIBS += $(shell $(WOLFSSL_BUILDER) --libs-only-L)
+	# TODO: explore use of LIBS += -Wl,-Bstatic $(shell $(SSL_BUILDER) --libs-only-l)
+	LIBS += -l:libwolfssl.a -l:libz.a -l:libdl.a
+else
+	## when linking against static libs compiled from sources
+	DEFS += -I$(WOLFSSL_STATIC_SRCPATH)/include
+	LIBS += $(WOLFSSL_STATIC_SRCPATH)/libwolfssl.a
+endif # ifneq ($(WOLFSSL_STATIC_SRCLIB),yes)
+
+endif # ifneq ($(WOLFSSL_STATIC),yes)
+
+else # ifneq ($(SSL_BUILDER),)
+
+	DEFS += -I$(LOCALBASE)/wolfssl/include
+	LIBS += -L$(LOCALBASE)/lib \
+			-L$(LOCALBASE)/lib64  \
+			-lwolfssl
+endif # ifneq ($(SSL_BUILDER),)
+
+LIBS+= $(TLS_EXTRA_LIBS)
+
+# dcm: tls.cfg installed via local 'install-cfg' to update paths
+#MOD_INSTALL_CFGS=tls.cfg
+
+include ../../Makefile.modules
+
+install-tls-cert: $(cfg_prefix)/$(cfg_dir)
+	MAIN_NAME=$(MAIN_NAME) ./tls_cert.sh -d $(cfg_prefix)/$(cfg_dir)
+
+install-cfg:
+	@if ! [ -d $(cfg_prefix)/$(cfg_dir) ]; then \
+		mkdir -p "$(cfg_prefix)/$(cfg_dir)" ; \
+	fi
+	@$(call try_err, $(INSTALL_TOUCH) \
+			"$(cfg_prefix)/$(cfg_dir)tls.cfg.sample" )
+	@sed -e "s#\/usr/local/etc/kamailio/#$(cfg_target)#g" \
+			-e "s#kamailio-selfsigned#$(MAIN_NAME)-selfsigned#g" \
+				< ./tls.cfg > "$(cfg_prefix)/$(cfg_dir)tls.cfg.sample"
+	@if [ -z "${skip_cfg_install}" -a \
+			! -f "$(cfg_prefix)/$(cfg_dir)tls.cfg" ]; then \
+		mv -f "$(cfg_prefix)/$(cfg_dir)tls.cfg.sample" \
+						"$(cfg_prefix)/$(cfg_dir)tls.cfg" ; \
+	fi
+