busybox/networking/vconfig.c

/* vi: set sw=4 ts=4: */
/*
 * vconfig implementation for busybox
 *
 * Copyright (C) 2001  Manuel Novoa III  <mjn3@codepoet.org>
 *
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */
//config:config VCONFIG
//config:	bool "vconfig (2.6 kb)"
//config:	default y
//config:	help
//config:	Creates, removes, and configures VLAN interfaces

//applet:IF_VCONFIG(APPLET_NOEXEC(vconfig, vconfig, BB_DIR_SBIN, BB_SUID_DROP, vconfig))

//kbuild:lib-$(CONFIG_VCONFIG) += vconfig.o

//usage:#define vconfig_trivial_usage
//usage:       "COMMAND [OPTIONS]"
//usage:#define vconfig_full_usage "\n\n"
//usage:       "Create and remove virtual ethernet devices\n"
//usage:     "\n	add IFACE VLAN_ID"
//usage:     "\n	rem VLAN_NAME"
//usage:     "\n	set_flag IFACE 0|1 VLAN_QOS"
//usage:     "\n	set_egress_map VLAN_NAME SKB_PRIO VLAN_QOS"
//usage:     "\n	set_ingress_map VLAN_NAME SKB_PRIO VLAN_QOS"
//usage:     "\n	set_name_type NAME_TYPE"

#include "libbb.h"
#include <net/if.h>

/* BB_AUDIT SUSv3 N/A */

/* Stuff from linux/if_vlan.h, kernel version 2.4.23 */
enum vlan_ioctl_cmds {
	ADD_VLAN_CMD,
	DEL_VLAN_CMD,
	SET_VLAN_INGRESS_PRIORITY_CMD,
	SET_VLAN_EGRESS_PRIORITY_CMD,
	GET_VLAN_INGRESS_PRIORITY_CMD,
	GET_VLAN_EGRESS_PRIORITY_CMD,
	SET_VLAN_NAME_TYPE_CMD,
	SET_VLAN_FLAG_CMD
};
enum vlan_name_types {
	VLAN_NAME_TYPE_PLUS_VID, /* Name will look like:  vlan0005 */
	VLAN_NAME_TYPE_RAW_PLUS_VID, /* name will look like:  eth1.0005 */
	VLAN_NAME_TYPE_PLUS_VID_NO_PAD, /* Name will look like:  vlan5 */
	VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD, /* Name will look like:  eth0.5 */
	VLAN_NAME_TYPE_HIGHEST
};

struct vlan_ioctl_args {
	int cmd; /* Should be one of the vlan_ioctl_cmds enum above. */
	char device1[24];

	union {
		char device2[24];
		int VID;
		unsigned int skb_priority;
		unsigned int name_type;
		unsigned int bind_type;
		unsigned int flag; /* Matches vlan_dev_info flags */
	} u;

	short vlan_qos;
};

#define VLAN_GROUP_ARRAY_LEN  4096
#define SIOCSIFVLAN           0x8983  /* Set 802.1Q VLAN options */

/* On entry, table points to the length of the current string
 * plus NUL terminator plus data length for the subsequent entry.
 * The return value is the last data entry for the matching string. */
static const char *xfind_str(const char *table, const char *str)
{
	while (strcasecmp(str, table + 1) != 0) {
		if (!table[0])
			bb_show_usage();
		table += table[0];
	}
	return table - 1;
}

static const char cmds[] ALIGN1 = {
	4, ADD_VLAN_CMD, 7,
	'a','d','d',0,
	3, DEL_VLAN_CMD, 7,
	'r','e','m',0,
	3, SET_VLAN_NAME_TYPE_CMD, 17,
	's','e','t','_','n','a','m','e','_','t','y','p','e',0,
	5, SET_VLAN_FLAG_CMD, 12,
	's','e','t','_','f','l','a','g',0,
	5, SET_VLAN_EGRESS_PRIORITY_CMD, 18,
	's','e','t','_','e','g','r','e','s','s','_','m','a','p',0,
	5, SET_VLAN_INGRESS_PRIORITY_CMD, 0,
	's','e','t','_','i','n','g','r','e','s','s','_','m','a','p',0,
};

static const char name_types[] ALIGN1 = {
	VLAN_NAME_TYPE_PLUS_VID, 16,
	'V','L','A','N','_','P','L','U','S','_','V','I','D',0,
	VLAN_NAME_TYPE_PLUS_VID_NO_PAD, 22,
	'V','L','A','N','_','P','L','U','S','_','V','I','D','_','N','O','_','P','A','D',0,
	VLAN_NAME_TYPE_RAW_PLUS_VID, 15,
	'D','E','V','_','P','L','U','S','_','V','I','D',0,
	VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD, 0,
	'D','E','V','_','P','L','U','S','_','V','I','D','_','N','O','_','P','A','D',0,
};

int vconfig_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int vconfig_main(int argc, char **argv)
{
	struct vlan_ioctl_args ifr;
	const char *p;
	int fd;

	memset(&ifr, 0, sizeof(ifr));

	++argv;
	if (!argv[0])
		bb_show_usage();
	p = xfind_str(cmds + 2, argv[0]);
	ifr.cmd = *p;
	if (argc != p[-1])
		bb_show_usage();

	if (ifr.cmd == SET_VLAN_NAME_TYPE_CMD) {
		/* set_name_type */
		ifr.u.name_type = *xfind_str(name_types + 1, argv[1]);
	} else {
		strncpy_IFNAMSIZ(ifr.device1, argv[1]);
		p = argv[2];

		/* I suppose one could try to combine some of the function calls below,
		 * since ifr.u.flag, ifr.u.VID, and ifr.u.skb_priority are all same-sized
		 * (unsigned) int members of a unions.  But because of the range checking,
		 * doing so wouldn't save that much space and would also make maintenance
		 * more of a pain.
		 */
		if (ifr.cmd == SET_VLAN_FLAG_CMD) {
			/* set_flag */
			ifr.u.flag = xatou_range(p, 0, 1);
			/* DM: in order to set reorder header, qos must be set */
			ifr.vlan_qos = xatou_range(argv[3], 0, 7);
		} else if (ifr.cmd == ADD_VLAN_CMD) {
			/* add */
			ifr.u.VID = xatou_range(p, 0, VLAN_GROUP_ARRAY_LEN - 1);
		} else if (ifr.cmd != DEL_VLAN_CMD) {
			/* set_{egress|ingress}_map */
			ifr.u.skb_priority = xatou(p);
			ifr.vlan_qos = xatou_range(argv[3], 0, 7);
		}
	}

	fd = xsocket(AF_INET, SOCK_STREAM, 0);
	ioctl_or_perror_and_die(fd, SIOCSIFVLAN, &ifr,
						"ioctl error for %s", argv[0]);

	return 0;
}