uhttpd: move Lua and TLS support into loadable plugins

contrib/package/uhttpd/Makefile

@@ -14,11 +14,15 @@ PKG_BUILD_DIR := $(BUILD_DIR)/$(PKG_NAME)
 
 include $(INCLUDE_DIR)/package.mk
 
-define Package/uhttpd
+define Package/uhttpd/default
   SECTION:=net
   CATEGORY:=Network
   TITLE:=uHTTPd - tiny, single threaded HTTP server
-  DEPENDS:=+liblua +libcyassl +zlib
+endef
+
+define Package/uhttpd
+  $(Package/uhttpd/default)
+  MENU:=1
 endef
 
 define Package/uhttpd/description
@@ -27,6 +31,29 @@ define Package/uhttpd/description
  HTTP daemon.
 endef
 
+
+define Package/uhttpd-mod-tls
+  $(Package/uhttpd/default)
+  TITLE+= (TLS plugin)
+  DEPENDS:=uhttpd +libcyassl
+endef
+
+define Package/uhttpd-mod-tls/description
+ The TLS plugin adds HTTPS support to uHTTPd.
+endef
+
+
+define Package/uhttpd-mod-lua
+  $(Package/uhttpd/default)
+  TITLE+= (Lua plugin)
+  DEPENDS:=uhttpd +liblua
+endef
+
+define Package/uhttpd-mod-lua/description
+ The Lua plugin adds a CGI-like Lua runtime interface to uHTTPd.
+endef
+
+
 # hack to use CyASSL headers
 TARGET_CFLAGS += -I$(firstword $(wildcard $(BUILD_DIR)/cyassl-*/include))
 
@@ -48,4 +75,17 @@ define Package/uhttpd/install
 	$(INSTALL_BIN) $(PKG_BUILD_DIR)/uhttpd $(1)/usr/sbin/uhttpd
 endef
 
+define Package/uhttpd-mod-tls/install
+	$(INSTALL_DIR) $(1)/usr/lib
+	$(INSTALL_BIN) $(PKG_BUILD_DIR)/uhttpd_tls.so $(1)/usr/lib/
+endef
+
+define Package/uhttpd-mod-lua/install
+	$(INSTALL_DIR) $(1)/usr/lib
+	$(INSTALL_BIN) $(PKG_BUILD_DIR)/uhttpd_lua.so $(1)/usr/lib/
+endef
+
+
 $(eval $(call BuildPackage,uhttpd))
+$(eval $(call BuildPackage,uhttpd-mod-tls))
+$(eval $(call BuildPackage,uhttpd-mod-lua))

contrib/package/uhttpd/src/Makefile

@@ -3,36 +3,50 @@ LUA_SUPPORT ?= 1
 TLS_SUPPORT ?= 1
 
 CFLAGS ?= -I./lua-5.1.4/src -I./cyassl-1.4.0/include -O0 -ggdb3
-LDFLAGS ?= -L./lua-5.1.4/src -L./cyassl-1.4.0/src/.libs -lm
+LDFLAGS ?= -L./lua-5.1.4/src -L./cyassl-1.4.0/src/.libs
 
 CFLAGS += -Wall --std=gnu99
-LDFLAGS += -lm -lcrypt
 
 OBJ = uhttpd.o uhttpd-file.o uhttpd-utils.o
+LIB = -Wl,--export-dynamic -lcrypt -ldl
+
+TLSLIB =
+LUALIB =
+
+
+world: compile
 
 ifeq ($(CGI_SUPPORT),1)
-	OBJ += uhttpd-cgi.o
+  OBJ += uhttpd-cgi.o
-	CFLAGS += -DHAVE_CGI
+  CFLAGS += -DHAVE_CGI
 endif
 
 ifeq ($(LUA_SUPPORT),1)
-	OBJ += uhttpd-lua.o
+  CFLAGS += -DHAVE_LUA
-	CFLAGS += -DHAVE_LUA
+  LUALIB = uhttpd_lua.so
-	LDFLAGS += -ldl -llua
+
+  $(LUALIB): uhttpd-lua.c
+		$(CC) $(CFLAGS) $(LDFLAGS) $(FPIC) \
+			-shared -lm -llua -ldl \
+			-o $(LUALIB) uhttpd-lua.c
 endif
 
 ifeq ($(TLS_SUPPORT),1)
-	OBJ += uhttpd-tls.o
+  CFLAGS += -DHAVE_TLS
-	CFLAGS += -DHAVE_TLS
+  TLSLIB = uhttpd_tls.so
-	LDFLAGS += -lpthread -lz -lcyassl
+
+  $(TLSLIB): uhttpd-tls.c
+		$(CC) $(CFLAGS) $(LDFLAGS) $(FPIC) \
+			-shared -lcyassl \
+			-o $(TLSLIB) uhttpd-tls.c
 endif
 
 %.o: %.c
-	$(CC) $(CFLAGS) -c -o $@ $< 
+	$(CC) $(CFLAGS) -c -o $@ $<
 
-compile: $(OBJ)
+compile: $(OBJ) $(TLSLIB) $(LUALIB)
-	$(CC) -o uhttpd $(LDFLAGS) $(OBJ)
+	$(CC) -o uhttpd $(LDFLAGS) $(LIB) $(OBJ)
 
 clean:
-	rm -f *.o uhttpd
+	rm -f *.o *.so uhttpd
 

contrib/package/uhttpd/src/uhttpd-lua.c

@@ -533,3 +533,9 @@ void uh_lua_request(struct client *cl, struct http_request *req, lua_State *L)
 	}
 }
 
+void uh_lua_close(lua_State *L)
+{
+	lua_close(L);
+}
+
+

contrib/package/uhttpd/src/uhttpd-lua.h

@@ -38,4 +38,6 @@ void uh_lua_request(
 	struct client *cl, struct http_request *req, lua_State *L
 );
 
+void uh_lua_close(lua_State *L);
+
 #endif

contrib/package/uhttpd/src/uhttpd-tls.c

@@ -33,6 +33,16 @@ SSL_CTX * uh_tls_ctx_init()
 	return c;
 }
 
+int uh_tls_ctx_cert(SSL_CTX *c, const char *file)
+{
+	return SSL_CTX_use_certificate_file(c, file, SSL_FILETYPE_ASN1);
+}
+
+int uh_tls_ctx_key(SSL_CTX *c, const char *file)
+{
+	return SSL_CTX_use_PrivateKey_file(c, file, SSL_FILETYPE_ASN1);
+}
+
 void uh_tls_ctx_free(struct listener *l)
 {
 	SSL_CTX_free(l->tls);
@@ -48,6 +58,16 @@ void uh_tls_client_accept(struct client *c)
 	}
 }
 
+int uh_tls_client_recv(struct client *c, void *buf, int len)
+{
+	return SSL_read(c->tls, buf, len);
+}
+
+int uh_tls_client_send(struct client *c, void *buf, int len)
+{
+	return SSL_write(c->tls, buf, len);
+}
+
 void uh_tls_client_close(struct client *c)
 {
 	if( c->tls )
@@ -58,3 +78,5 @@ void uh_tls_client_close(struct client *c)
 		c->tls = NULL;
 	}
 }
+
+

contrib/package/uhttpd/src/uhttpd-tls.h

@@ -22,9 +22,13 @@
 
 
 SSL_CTX * uh_tls_ctx_init();
-
+int uh_tls_ctx_cert(SSL_CTX *c, const char *file);
+int uh_tls_ctx_key(SSL_CTX *c, const char *file);
 void uh_tls_ctx_free(struct listener *l);
+
 void uh_tls_client_accept(struct client *c);
+int uh_tls_client_recv(struct client *c, void *buf, int len);
+int uh_tls_client_send(struct client *c, void *buf, int len);
 void uh_tls_client_close(struct client *c);
 
 #endif

contrib/package/uhttpd/src/uhttpd-utils.c

@@ -104,7 +104,7 @@ int uh_tcp_send(struct client *cl, const char *buf, int len)
 	{
 #ifdef HAVE_TLS
 		if( cl->tls )
-			return SSL_write(cl->tls, buf, len);
+			return cl->server->conf->tls_send(cl, (void *)buf, len);
 		else
 #endif
 			return send(cl->socket, buf, len, 0);
@@ -147,7 +147,7 @@ int uh_tcp_recv(struct client *cl, char *buf, int len)
 	{
 #ifdef HAVE_TLS
 		if( cl->tls )
-			rsz = SSL_read(cl->tls, (void *)&buf[sz], len);
+			rsz = cl->server->conf->tls_recv(cl, (void *)&buf[sz], len);
 		else
 #endif
 			rsz = recv(cl->socket, (void *)&buf[sz], len, 0);

contrib/package/uhttpd/src/uhttpd.c

@@ -417,6 +417,10 @@ int main (int argc, char **argv)
 	char bind[128];
 	char *port = NULL;
 
+	/* library handles */
+	void *tls_lib;
+	void *lua_lib;
+
 	/* clear the master and temp sets */
 	FD_ZERO(&used_fds);
 	FD_ZERO(&serv_fds);
@@ -445,11 +449,39 @@ int main (int argc, char **argv)
 	memset(bind, 0, sizeof(bind));
 
 #ifdef HAVE_TLS
-	/* init SSL context */
+	/* load TLS plugin */
-	if( ! (conf.tls = uh_tls_ctx_init()) )
+	if( ! (tls_lib = dlopen("uhttpd_tls.so", RTLD_LAZY | RTLD_GLOBAL)) )
 	{
-		fprintf(stderr, "Failed to initalize SSL context\n");
+		fprintf(stderr,
-		exit(1);
+			"Notice: Unable to load TLS plugin - disabling SSL support! "
+			"(Reason: %s)\n", dlerror()
+		);
+	}
+	else
+	{
+		/* resolve functions */
+		if( !(conf.tls_init   = dlsym(tls_lib, "uh_tls_ctx_init"))      ||
+		    !(conf.tls_cert   = dlsym(tls_lib, "uh_tls_ctx_cert"))      ||
+		    !(conf.tls_key    = dlsym(tls_lib, "uh_tls_ctx_key"))       ||
+		    !(conf.tls_free   = dlsym(tls_lib, "uh_tls_ctx_free"))      ||
+			!(conf.tls_accept = dlsym(tls_lib, "uh_tls_client_accept")) ||
+			!(conf.tls_close  = dlsym(tls_lib, "uh_tls_client_close"))  ||
+			!(conf.tls_recv   = dlsym(tls_lib, "uh_tls_client_recv"))   ||
+			!(conf.tls_send   = dlsym(tls_lib, "uh_tls_client_send"))
+		) {
+			fprintf(stderr,
+				"Error: Failed to lookup required symbols "
+				"in TLS plugin: %s\n", dlerror()
+			);
+			exit(1);
+		}
+
+		/* init SSL context */
+		if( ! (conf.tls = conf.tls_init()) )
+		{
+			fprintf(stderr, "Error: Failed to initalize SSL context\n");
+			exit(1);
+		}
 	}
 #endif
 
@@ -477,12 +509,23 @@ int main (int argc, char **argv)
 				}
 
 				if( opt == 's' )
+				{
+					if( !conf.tls )
+					{
+						fprintf(stderr,
+							"Notice: TLS support is disabled, "
+							"ignoring '-s %s'\n", optarg
+						);
+						continue;
+					}
+
 					tls = 1;
+				}
 
 				/* bind sockets */
 				bound += uh_socket_bind(
 					&serv_fds, &max_fd, bind[0] ? bind : NULL, port,
-					&hints,	tls, &conf
+					&hints,	(opt == 's'), &conf
 				);
 
 				break;
@@ -490,24 +533,34 @@ int main (int argc, char **argv)
 #ifdef HAVE_TLS
 			/* certificate */
 			case 'C':
-				if( SSL_CTX_use_certificate_file(conf.tls, optarg, SSL_FILETYPE_ASN1) < 1 )
+				if( conf.tls )
 				{
-					fprintf(stderr, "Invalid certificate file given\n");
+					if( conf.tls_cert(conf.tls, optarg) < 1 )
-					exit(1);
+					{
+						fprintf(stderr,
+							"Error: Invalid certificate file given\n");
+						exit(1);
+					}
+
+					keys++;
 				}
 
-				keys++;
 				break;
 
 			/* key */
 			case 'K':
-				if( SSL_CTX_use_PrivateKey_file(conf.tls, optarg, SSL_FILETYPE_ASN1) < 1 )
+				if( conf.tls )
 				{
-					fprintf(stderr, "Invalid private key file given\n");
+					if( conf.tls_key(conf.tls, optarg) < 1 )
-					exit(1);
+					{
+						fprintf(stderr,
+							"Error: Invalid private key file given\n");
+						exit(1);
+					}
+
+					keys++;
 				}
 
-				keys++;
 				break;
 #endif
 
@@ -515,7 +568,8 @@ int main (int argc, char **argv)
 			case 'h':
 				if( ! realpath(optarg, conf.docroot) )
 				{
-					fprintf(stderr, "Invalid directory %s: %s\n", optarg, strerror(errno));
+					fprintf(stderr, "Error: Invalid directory %s: %s\n",
+						optarg, strerror(errno));
 					exit(1);
 				}
 				break;
@@ -604,21 +658,21 @@ int main (int argc, char **argv)
 #ifdef HAVE_TLS
 	if( (tls == 1) && (keys < 2) )
 	{
-		fprintf(stderr, "Missing private key or certificate file\n");
+		fprintf(stderr, "Error: Missing private key or certificate file\n");
 		exit(1);
 	}
 #endif
 
 	if( bound < 1 )
 	{
-		fprintf(stderr, "No sockets bound, unable to continue\n");
+		fprintf(stderr, "Error: No sockets bound, unable to continue\n");
 		exit(1);
 	}
 
 	/* default docroot */
 	if( !conf.docroot[0] && !realpath(".", conf.docroot) )
 	{
-		fprintf(stderr, "Can not determine default document root: %s\n",
+		fprintf(stderr, "Error: Can not determine default document root: %s\n",
 			strerror(errno));
 		exit(1);
 	}
@@ -637,14 +691,37 @@ int main (int argc, char **argv)
 #endif
 
 #ifdef HAVE_LUA
-	/* init Lua runtime if handler is specified */
+	/* load Lua plugin */
-	if( conf.lua_handler )
+	if( ! (lua_lib = dlopen("uhttpd_lua.so", RTLD_LAZY | RTLD_GLOBAL)) )
 	{
-		/* default lua prefix */
+		fprintf(stderr,
-		if( ! conf.lua_prefix )
+			"Notice: Unable to load Lua plugin - disabling Lua support! "
-			conf.lua_prefix = "/lua";
+			"(Reason: %s)\n", dlerror()
+		);
+	}
+	else
+	{
+		/* resolve functions */
+		if( !(conf.lua_init    = dlsym(lua_lib, "uh_lua_init"))    ||
+		    !(conf.lua_close   = dlsym(lua_lib, "uh_lua_close"))   ||
+		    !(conf.lua_request = dlsym(lua_lib, "uh_lua_request"))
+		) {
+			fprintf(stderr,
+				"Error: Failed to lookup required symbols "
+				"in Lua plugin: %s\n", dlerror()
+			);
+			exit(1);
+		}
 
-		L = uh_lua_init(conf.lua_handler);
+		/* init Lua runtime if handler is specified */
+		if( conf.lua_handler )
+		{
+			/* default lua prefix */
+			if( ! conf.lua_prefix )
+				conf.lua_prefix = "/lua";
+
+			L = conf.lua_init(conf.lua_handler);
+		}
 	}
 #endif
 
@@ -711,7 +788,8 @@ int main (int argc, char **argv)
 						{
 #ifdef HAVE_TLS
 							/* setup client tls context */
-							uh_tls_client_accept(cl);
+							if( conf.tls )
+								conf.tls_accept(cl);
 #endif
 
 							/* add client socket to global fdset */
@@ -753,7 +831,7 @@ int main (int argc, char **argv)
 						/* Lua request? */
 						if( L && uh_path_match(conf.lua_prefix, req->url) )
 						{
-							uh_lua_request(cl, req, L);
+							conf.lua_request(cl, req, L);
 						}
 						else
 #endif
@@ -793,7 +871,8 @@ int main (int argc, char **argv)
 
 #ifdef HAVE_TLS
 					/* free client tls context */
-					uh_tls_client_close(cl);
+					if( conf.tls )
+						conf.tls_close(cl);
 #endif
 
 					cleanup:
@@ -812,7 +891,7 @@ int main (int argc, char **argv)
 #ifdef HAVE_LUA
 	/* destroy the Lua state */
 	if( L != NULL )
-		lua_close(L);
+		conf.lua_close(L);
 #endif
 
 	return 0;

contrib/package/uhttpd/src/uhttpd.h

@@ -32,6 +32,13 @@
 #include <netdb.h>
 #include <ctype.h>
 
+#include <dlfcn.h>
+
+
+#ifdef HAVE_LUA
+#include <lua.h>
+#endif
+
 #ifdef HAVE_TLS
 #include <openssl/ssl.h>
 #endif
@@ -48,6 +55,9 @@
 #define UH_HTTP_MSG_HEAD	1
 #define UH_HTTP_MSG_POST	2
 
+struct listener;
+struct client;
+struct http_request;
 
 struct config {
 	char docroot[PATH_MAX];
@@ -59,11 +69,22 @@ struct config {
 #ifdef HAVE_LUA
 	char *lua_prefix;
 	char *lua_handler;
+	lua_State * (*lua_init) (const char *handler);
+	void (*lua_close) (lua_State *L);
+	void (*lua_request) (struct client *cl, struct http_request *req, lua_State *L);
 #endif
 #ifdef HAVE_TLS
 	char *cert;
 	char *key;
 	SSL_CTX *tls;
+	SSL_CTX * (*tls_init) (void);
+	int (*tls_cert) (SSL_CTX *c, const char *file);
+	int (*tls_key) (SSL_CTX *c, const char *file);
+	void (*tls_free) (struct listener *l);
+	void (*tls_accept) (struct client *c);
+	void (*tls_close) (struct client *c);
+	int (*tls_recv) (struct client *c, void *buf, int len);
+	int (*tls_send) (struct client *c, void *buf, int len);
 #endif
 };