source: MondoRescue/branches/3.3/mindi-busybox/networking/nameif.c@ 3734

/* vi: set sw=4 ts=4: */
/*
 * nameif.c - Naming Interfaces based on MAC address for busybox.
 *
 * Written 2000 by Andi Kleen.
 * Busybox port 2002 by Nick Fedchik <nick@fedchik.org.ua>
 *          Glenn McGrath
 * Extended matching support 2008 by Nico Erfurth <masta@perlgolf.de>
 *
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */

//config:config NAMEIF
//config:   bool "nameif"
//config:   default y
//config:   select PLATFORM_LINUX
//config:   select FEATURE_SYSLOG
//config:   help
//config:     nameif is used to rename network interface by its MAC address.
//config:     Renamed interfaces MUST be in the down state.
//config:     It is possible to use a file (default: /etc/mactab)
//config:     with list of new interface names and MACs.
//config:     Maximum interface name length: IFNAMSIZ = 16
//config:     File fields are separated by space or tab.
//config:     File format:
//config:     # Comment
//config:     new_interface_name    XX:XX:XX:XX:XX:XX
//config:
//config:config FEATURE_NAMEIF_EXTENDED
//config:   bool "Extended nameif"
//config:   default y
//config:   depends on NAMEIF
//config:   help
//config:     This extends the nameif syntax to support the bus_info, driver,
//config:     phyaddr selectors. The syntax is compatible to the normal nameif.
//config:     File format:
//config:       new_interface_name  driver=asix bus=usb-0000:00:08.2-3
//config:       new_interface_name  bus=usb-0000:00:08.2-3 00:80:C8:38:91:B5
//config:       new_interface_name  phy_address=2 00:80:C8:38:91:B5
//config:       new_interface_name  mac=00:80:C8:38:91:B5
//config:       new_interface_name  00:80:C8:38:91:B5

//usage:#define nameif_trivial_usage
//usage:    IF_NOT_FEATURE_NAMEIF_EXTENDED(
//usage:        "[-s] [-c FILE] [IFNAME HWADDR]..."
//usage:    )
//usage:    IF_FEATURE_NAMEIF_EXTENDED(
//usage:        "[-s] [-c FILE] [IFNAME SELECTOR]..."
//usage:    )
//usage:#define nameif_full_usage "\n\n"
//usage:    "Rename network interface while it in the down state."
//usage:    IF_NOT_FEATURE_NAMEIF_EXTENDED(
//usage:     "\nThe device with address HWADDR is renamed to IFACE."
//usage:    )
//usage:    IF_FEATURE_NAMEIF_EXTENDED(
//usage:     "\nThe device matched by SELECTOR is renamed to IFACE."
//usage:     "\nSELECTOR can be a combination of:"
//usage:     "\n    driver=STRING"
//usage:     "\n    bus=STRING"
//usage:     "\n    phy_address=NUM"
//usage:     "\n    [mac=]XX:XX:XX:XX:XX:XX"
//usage:    )
//usage:     "\n"
//usage:     "\n    -c FILE Configuration file (default: /etc/mactab)"
//usage:     "\n    -s  Log to syslog"
//usage:
//usage:#define nameif_example_usage
//usage:       "$ nameif -s dmz0 00:A0:C9:8C:F6:3F\n"
//usage:       " or\n"
//usage:       "$ nameif -c /etc/my_mactab_file\n"

#include "libbb.h"
#include <syslog.h>
#include <net/if.h>
#include <netinet/ether.h>
#include <linux/sockios.h>

#ifndef IFNAMSIZ
#define IFNAMSIZ 16
#endif

/* Taken from linux/sockios.h */
#define SIOCSIFNAME  0x8923  /* set interface name */

/* Octets in one Ethernet addr, from <linux/if_ether.h> */
#define ETH_ALEN     6

#ifndef ifr_newname
#define ifr_newname ifr_ifru.ifru_slave
#endif

typedef struct ethtable_s {
    struct ethtable_s *next;
    struct ethtable_s *prev;
    char *ifname;
    struct ether_addr *mac;
#if ENABLE_FEATURE_NAMEIF_EXTENDED
    char *bus_info;
    char *driver;
    int32_t phy_address;
#endif
} ethtable_t;

#if ENABLE_FEATURE_NAMEIF_EXTENDED
/* Cut'n'paste from ethtool.h */
#define ETHTOOL_BUSINFO_LEN 32
/* these strings are set to whatever the driver author decides... */
struct ethtool_drvinfo {
    uint32_t cmd;
    char  driver[32]; /* driver short name, "tulip", "eepro100" */
    char  version[32];  /* driver version string */
    char  fw_version[32]; /* firmware version string, if applicable */
    char  bus_info[ETHTOOL_BUSINFO_LEN];  /* Bus info for this IF. */
    /* For PCI devices, use pci_dev->slot_name. */
    char  reserved1[32];
    char  reserved2[16];
    uint32_t n_stats;  /* number of u64's from ETHTOOL_GSTATS */
    uint32_t testinfo_len;
    uint32_t eedump_len; /* Size of data from ETHTOOL_GEEPROM (bytes) */
    uint32_t regdump_len;  /* Size of data from ETHTOOL_GREGS (bytes) */
};

struct ethtool_cmd {
    uint32_t   cmd;
    uint32_t   supported;      /* Features this interface supports */
    uint32_t   advertising;    /* Features this interface advertises */
    uint16_t   speed;          /* The forced speed, 10Mb, 100Mb, gigabit */
    uint8_t    duplex;         /* Duplex, half or full */
    uint8_t    port;           /* Which connector port */
    uint8_t    phy_address;
    uint8_t    transceiver;    /* Which transceiver to use */
    uint8_t    autoneg;        /* Enable or disable autonegotiation */
    uint32_t   maxtxpkt;       /* Tx pkts before generating tx int */
    uint32_t   maxrxpkt;       /* Rx pkts before generating rx int */
    uint16_t   speed_hi;
    uint16_t   reserved2;
    uint32_t   reserved[3];
};

#define ETHTOOL_GSET      0x00000001 /* Get settings. */
#define ETHTOOL_GDRVINFO  0x00000003 /* Get driver info. */
#endif


static void nameif_parse_selector(ethtable_t *ch, char *selector)
{
    struct ether_addr *lmac;
#if ENABLE_FEATURE_NAMEIF_EXTENDED
    int found_selector = 0;

    while (*selector) {
        char *next;
#endif
        selector = skip_whitespace(selector);
#if ENABLE_FEATURE_NAMEIF_EXTENDED
        ch->phy_address = -1;
        if (*selector == '\0')
            break;
        /* Search for the end .... */
        next = skip_non_whitespace(selector);
        if (*next)
            *next++ = '\0';
        /* Check for selectors, mac= is assumed */
        if (is_prefixed_with(selector, "bus=")) {
            ch->bus_info = xstrdup(selector + 4);
            found_selector++;
        } else if (is_prefixed_with(selector, "driver=")) {
            ch->driver = xstrdup(selector + 7);
            found_selector++;
        } else if (is_prefixed_with(selector, "phyaddr=")) {
            ch->phy_address = xatoi_positive(selector + 8);
            found_selector++;
        } else {
#endif
            lmac = xmalloc(ETH_ALEN);
            ch->mac = ether_aton_r(selector + (is_prefixed_with(selector, "mac=") ? 4 : 0), lmac);
            if (ch->mac == NULL)
                bb_error_msg_and_die("can't parse %s", selector);
#if  ENABLE_FEATURE_NAMEIF_EXTENDED
            found_selector++;
        };
        selector = next;
    }
    if (found_selector == 0)
        bb_error_msg_and_die("no selectors found for %s", ch->ifname);
#endif
}

static void prepend_new_eth_table(ethtable_t **clist, char *ifname, char *selector)
{
    ethtable_t *ch;
    if (strlen(ifname) >= IFNAMSIZ)
        bb_error_msg_and_die("interface name '%s' too long", ifname);
    ch = xzalloc(sizeof(*ch));
    ch->ifname = xstrdup(ifname);
    nameif_parse_selector(ch, selector);
    ch->next = *clist;
    if (*clist)
        (*clist)->prev = ch;
    *clist = ch;
}

#if ENABLE_FEATURE_CLEAN_UP
static void delete_eth_table(ethtable_t *ch)
{
    free(ch->ifname);
#if ENABLE_FEATURE_NAMEIF_EXTENDED
    free(ch->bus_info);
    free(ch->driver);
#endif
    free(ch->mac);
    free(ch);
};
#else
void delete_eth_table(ethtable_t *ch);
#endif

int nameif_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int nameif_main(int argc UNUSED_PARAM, char **argv)
{
    ethtable_t *clist = NULL;
    const char *fname = "/etc/mactab";
    int ctl_sk;
    ethtable_t *ch;
    parser_t *parser;
    char *token[2];

    if (1 & getopt32(argv, "sc:", &fname)) {
        openlog(applet_name, 0, LOG_LOCAL0);
        /* Why not just "="? I assume logging to stderr
         * can't hurt. 2>/dev/null if you don't like it: */
        logmode |= LOGMODE_SYSLOG;
    }
    argv += optind;

    if (argv[0]) {
        do {
            if (!argv[1])
                bb_show_usage();
            prepend_new_eth_table(&clist, argv[0], argv[1]);
            argv += 2;
        } while (*argv);
    } else {
        parser = config_open(fname);
        while (config_read(parser, token, 2, 2, "# \t", PARSE_NORMAL))
            prepend_new_eth_table(&clist, token[0], token[1]);
        config_close(parser);
    }

    ctl_sk = xsocket(PF_INET, SOCK_DGRAM, 0);
    parser = config_open2("/proc/net/dev", xfopen_for_read);

    while (clist && config_read(parser, token, 2, 2, "\0: \t", PARSE_NORMAL)) {
        struct ifreq ifr;
#if  ENABLE_FEATURE_NAMEIF_EXTENDED
        struct ethtool_drvinfo drvinfo;
        struct ethtool_cmd eth_settings;
#endif
        if (parser->lineno <= 2)
            continue; /* Skip the first two lines */

        /* Find the current interface name and copy it to ifr.ifr_name */
        memset(&ifr, 0, sizeof(struct ifreq));
        strncpy_IFNAMSIZ(ifr.ifr_name, token[0]);

#if ENABLE_FEATURE_NAMEIF_EXTENDED
        /* Check for phy address */
        memset(&eth_settings, 0, sizeof(eth_settings));
        eth_settings.cmd = ETHTOOL_GSET;
        ifr.ifr_data = (caddr_t) &eth_settings;
        ioctl(ctl_sk, SIOCETHTOOL, &ifr);

        /* Check for driver etc. */
        memset(&drvinfo, 0, sizeof(drvinfo));
        drvinfo.cmd = ETHTOOL_GDRVINFO;
        ifr.ifr_data = (caddr_t) &drvinfo;
        /* Get driver and businfo first, so we have it in drvinfo */
        ioctl(ctl_sk, SIOCETHTOOL, &ifr);
#endif
        ioctl(ctl_sk, SIOCGIFHWADDR, &ifr);

        /* Search the list for a matching device */
        for (ch = clist; ch; ch = ch->next) {
#if ENABLE_FEATURE_NAMEIF_EXTENDED
            if (ch->bus_info && strcmp(ch->bus_info, drvinfo.bus_info) != 0)
                continue;
            if (ch->driver && strcmp(ch->driver, drvinfo.driver) != 0)
                continue;
            if (ch->phy_address != -1 && ch->phy_address != eth_settings.phy_address)
                continue;
#endif
            if (ch->mac && memcmp(ch->mac, ifr.ifr_hwaddr.sa_data, ETH_ALEN) != 0)
                continue;
            /* if we came here, all selectors have matched */
            goto found;
        }
        /* Nothing found for current interface */
        continue;
 found:
        if (strcmp(ifr.ifr_name, ch->ifname) != 0) {
            strcpy(ifr.ifr_newname, ch->ifname);
            ioctl_or_perror_and_die(ctl_sk, SIOCSIFNAME, &ifr,
                    "can't change ifname %s to %s",
                    ifr.ifr_name, ch->ifname);
        }
        /* Remove list entry of renamed interface */
        if (ch->prev != NULL)
            ch->prev->next = ch->next;
        else
            clist = ch->next;
        if (ch->next != NULL)
            ch->next->prev = ch->prev;
        if (ENABLE_FEATURE_CLEAN_UP)
            delete_eth_table(ch);
    } /* while */

    if (ENABLE_FEATURE_CLEAN_UP) {
        ethtable_t *next;
        for (ch = clist; ch; ch = next) {
            next = ch->next;
            delete_eth_table(ch);
        }
        config_close(parser);
    };

    return 0;
}