includes.c

/*
 * firewall3 - 3rd OpenWrt UCI firewall implementation
 *
 *   Copyright (C) 2013 Jo-Philipp Wich <jo@mein.io>
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "includes.h"


const struct fw3_option fw3_include_opts[] = {
	FW3_OPT("enabled",             bool,           include,     enabled),

	FW3_OPT("path",                string,         include,     path),
	FW3_OPT("type",                include_type,   include,     type),
	FW3_OPT("family",              family,         include,     family),
	FW3_OPT("reload",              bool,           include,     reload),

	{ }
};

static bool
check_include(struct fw3_state *state, struct fw3_include *include, struct uci_element *e)
{
	if (!include->enabled)
		return false;

	if (!include->path)
	{
		warn_section("include", include, e, "must specify a path");
		return false;
	}

	if (include->type == FW3_INC_TYPE_RESTORE && !include->family)
		warn_section("include", include, e, "does not specify a family, include will get"
				"loaded with both iptables-restore and ip6tables-restore!");

	return true;
}

static struct fw3_include *
fw3_alloc_include(struct fw3_state *state)
{
	struct fw3_include *include;

	include = calloc(1, sizeof(*include));
	if (!include)
		return NULL;

	include->enabled = true;

	list_add_tail(&include->list, &state->includes);

	return include;
}

void
fw3_load_includes(struct fw3_state *state, struct uci_package *p,
		struct blob_attr *a)
{
	struct uci_section *s;
	struct uci_element *e;
	struct fw3_include *include;
	struct blob_attr *entry;
	unsigned rem;

	INIT_LIST_HEAD(&state->includes);

	blob_for_each_attr(entry, a, rem)
	{
		const char *type;
		const char *name = "ubus include";

		if (!fw3_attr_parse_name_type(entry, &name, &type))
			continue;

		if (strcmp(type, "script") && strcmp(type, "restore"))
			continue;

		include = fw3_alloc_include(state);
		if (!include)
			continue;

		if (!fw3_parse_blob_options(include, fw3_include_opts, entry, name))
		{
			warn_section("include", include, NULL, "skipped due to invalid options");
			fw3_free_include(include);
			continue;
		}

		if (!check_include(state, include, NULL))
			fw3_free_include(include);
	}

	uci_foreach_element(&p->sections, e)
	{
		s = uci_to_section(e);

		if (strcmp(s->type, "include"))
			continue;

		include = fw3_alloc_include(state);
		if (!include)
			continue;

		include->name = e->name;

		if (!fw3_parse_options(include, fw3_include_opts, s))
			warn_elem(e, "has invalid options");

		if (!check_include(state, include, e))
			fw3_free_include(include);
	}
}


static void
print_include(struct fw3_include *include)
{
	FILE *f;
	char line[1024];

	info(" * Loading include '%s'", include->path);

	if (!(f = fopen(include->path, "r")))
	{
		info("   ! Skipping due to open error: %s", strerror(errno));
		return;
	}

	while (fgets(line, sizeof(line), f))
		fw3_pr("%s", line);

	fclose(f);
}

void
fw3_print_includes(struct fw3_state *state, enum fw3_family family, bool reload)
{
	struct fw3_include *include;

	bool exec = false;
	const char *restore = "iptables-restore";

	if (family == FW3_FAMILY_V6)
		restore = "ip6tables-restore";

	list_for_each_entry(include, &state->includes, list)
	{
		if (reload && !include->reload)
			continue;

		if (include->type != FW3_INC_TYPE_RESTORE)
			continue;

		if (!fw3_is_family(include, family))
			continue;

		if (!exec)
		{
			exec = fw3_command_pipe(false, restore, "--noflush");

			if (!exec)
				return;
		}

		print_include(include);
	}

	if (exec)
		fw3_command_close();
}


static void
run_include(struct fw3_include *include)
{
	int rv;
	struct stat s;
	const char *tmpl =
		"config() { "
			"echo \"You cannot use UCI in firewall includes!\" >&2; "
			"exit 1; "
		"}; . %s";

	char buf[PATH_MAX + sizeof(tmpl)];

	info(" * Running script '%s'", include->path);

	if (stat(include->path, &s))
	{
		info("   ! Skipping due to path error: %s", strerror(errno));
		return;
	}

	snprintf(buf, sizeof(buf), tmpl, include->path);
	rv = system(buf);

	if (rv)
		info("   ! Failed with exit code %u", WEXITSTATUS(rv));
}

void
fw3_run_includes(struct fw3_state *state, bool reload)
{
	struct fw3_include *include;

	list_for_each_entry(include, &state->includes, list)
	{
		if (reload && !include->reload)
			continue;

		if (include->type == FW3_INC_TYPE_SCRIPT)
			run_include(include);
	}
}