/* 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 (2.5 kb)"
//config:       default y
//config:       select PLATFORM_LINUX
//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;
}