/* vi: set sw=4 ts=4: */
/*
 * stolen from net-tools-1.59 and stripped down for busybox by
 *                      Erik Andersen <andersen@codepoet.org>
 *
 * Heavily modified by Manuel Novoa III       Mar 12, 2001
 *
 * Added print_bytes_scaled function to reduce code size.
 * Added some (potentially) missing defines.
 * Improved display support for -a and for a named interface.
 *
 * -----------------------------------------------------------
 *
 * ifconfig   This file contains an implementation of the command
 *              that either displays or sets the characteristics of
 *              one or more of the system's networking interfaces.
 *
 *
 * Author:      Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
 *              and others.  Copyright 1993 MicroWalt Corporation
 *
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 *
 * Patched to support 'add' and 'del' keywords for INET(4) addresses
 * by Mrs. Brisby <mrs.brisby@nimh.org>
 *
 * {1.34} - 19980630 - Arnaldo Carvalho de Melo <acme@conectiva.com.br>
 *                     - gettext instead of catgets for i18n
 *          10/1998  - Andi Kleen. Use interface list primitives.
 *          20001008 - Bernd Eckenfels, Patch from RH for setting mtu
 *                      (default AF was wrong)
 */
#include "libbb.h"
#include "inet_common.h"
#include <net/if.h>
#include <net/if_arp.h>
#ifdef HAVE_NET_ETHERNET_H
# include <net/ethernet.h>
#endif

#if ENABLE_FEATURE_HWIB
/* #include <linux/if_infiniband.h> */
# undef INFINIBAND_ALEN
# define INFINIBAND_ALEN 20
#endif

#if ENABLE_FEATURE_IPV6
# define HAVE_AFINET6 1
#else
# undef HAVE_AFINET6
#endif

#define _PATH_PROCNET_DEV               "/proc/net/dev"
#define _PATH_PROCNET_IFINET6           "/proc/net/if_inet6"

#ifdef HAVE_AFINET6
# ifndef _LINUX_IN6_H
/*
 * This is from linux/include/net/ipv6.h
 */
struct in6_ifreq {
        struct in6_addr ifr6_addr;
        uint32_t ifr6_prefixlen;
        unsigned int ifr6_ifindex;
};
# endif
#endif /* HAVE_AFINET6 */

/* Defines for glibc2.0 users. */
#ifndef SIOCSIFTXQLEN
# define SIOCSIFTXQLEN      0x8943
# define SIOCGIFTXQLEN      0x8942
#endif

/* ifr_qlen is ifru_ivalue, but it isn't present in 2.0 kernel headers */
#ifndef ifr_qlen
# define ifr_qlen        ifr_ifru.ifru_mtu
#endif

#ifndef HAVE_TXQUEUELEN
# define HAVE_TXQUEUELEN 1
#endif

#ifndef IFF_DYNAMIC
# define IFF_DYNAMIC     0x8000 /* dialup device with changing addresses */
#endif

/* Display an Internet socket address. */
static const char* FAST_FUNC INET_sprint(struct sockaddr *sap, int numeric)
{
        if (sap->sa_family == 0xFFFF || sap->sa_family == 0)
                return "[NONE SET]";
        return auto_string(INET_rresolve((struct sockaddr_in *) sap, numeric, 0xffffff00));
}

#ifdef UNUSED_AND_BUGGY
static int INET_getsock(char *bufp, struct sockaddr *sap)
{
        char *sp = bufp, *bp;
        unsigned int i;
        unsigned val;
        struct sockaddr_in *sock_in;

        sock_in = (struct sockaddr_in *) sap;
        sock_in->sin_family = AF_INET;
        sock_in->sin_port = 0;

        val = 0;
        bp = (char *) &val;
        for (i = 0; i < sizeof(sock_in->sin_addr.s_addr); i++) {
                *sp = toupper(*sp);

                if ((unsigned)(*sp - 'A') <= 5)
                        bp[i] |= (int) (*sp - ('A' - 10));
                else if (isdigit(*sp))
                        bp[i] |= (int) (*sp - '0');
                else
                        return -1;

                bp[i] <<= 4;
                sp++;
                *sp = toupper(*sp);

                if ((unsigned)(*sp - 'A') <= 5)
                        bp[i] |= (int) (*sp - ('A' - 10));
                else if (isdigit(*sp))
                        bp[i] |= (int) (*sp - '0');
                else
                        return -1;

                sp++;
        }
        sock_in->sin_addr.s_addr = htonl(val);

        return (sp - bufp);
}
#endif

static int FAST_FUNC INET_input(/*int type,*/ const char *bufp, struct sockaddr *sap)
{
        return INET_resolve(bufp, (struct sockaddr_in *) sap, 0);
/*
        switch (type) {
        case 1:
                return (INET_getsock(bufp, sap));
        case 256:
                return (INET_resolve(bufp, (struct sockaddr_in *) sap, 1));
        default:
                return (INET_resolve(bufp, (struct sockaddr_in *) sap, 0));
        }
*/
}

static const struct aftype inet_aftype = {
        .name   = "inet",
        .title  = "DARPA Internet",
        .af     = AF_INET,
        .alen   = 4,
        .sprint = INET_sprint,
        .input  = INET_input,
};

#ifdef HAVE_AFINET6

/* Display an Internet socket address. */
/* dirty! struct sockaddr usually doesn't suffer for inet6 addresses, fst. */
static const char* FAST_FUNC INET6_sprint(struct sockaddr *sap, int numeric)
{
        if (sap->sa_family == 0xFFFF || sap->sa_family == 0)
                return "[NONE SET]";
        return auto_string(INET6_rresolve((struct sockaddr_in6 *) sap, numeric));
}

#ifdef UNUSED
static int INET6_getsock(char *bufp, struct sockaddr *sap)
{
        struct sockaddr_in6 *sin6;

        sin6 = (struct sockaddr_in6 *) sap;
        sin6->sin6_family = AF_INET6;
        sin6->sin6_port = 0;

        if (inet_pton(AF_INET6, bufp, sin6->sin6_addr.s6_addr) <= 0)
                return -1;

        return 16;                      /* ?;) */
}
#endif

static int FAST_FUNC INET6_input(/*int type,*/ const char *bufp, struct sockaddr *sap)
{
        return INET6_resolve(bufp, (struct sockaddr_in6 *) sap);
/*
        switch (type) {
        case 1:
                return (INET6_getsock(bufp, sap));
        default:
                return (INET6_resolve(bufp, (struct sockaddr_in6 *) sap));
        }
*/
}

static const struct aftype inet6_aftype = {
        .name   = "inet6",
        .title  = "IPv6",
        .af     = AF_INET6,
        .alen   = sizeof(struct in6_addr),
        .sprint = INET6_sprint,
        .input  = INET6_input,
};

#endif /* HAVE_AFINET6 */

/* Display an UNSPEC address. */
static char* FAST_FUNC UNSPEC_print(unsigned char *ptr)
{
        char *buff;
        char *pos;
        unsigned int i;

        buff = auto_string(xmalloc(sizeof(struct sockaddr) * 3 + 1));
        pos = buff;
        for (i = 0; i < sizeof(struct sockaddr); i++) {
                /* careful -- not every libc's sprintf returns # bytes written */
                sprintf(pos, "%02X-", *ptr++);
                pos += 3;
        }
        /* Erase trailing "-".  Works as long as sizeof(struct sockaddr) != 0 */
        *--pos = '\0';
        return buff;
}

/* Display an UNSPEC socket address. */
static const char* FAST_FUNC UNSPEC_sprint(struct sockaddr *sap, int numeric UNUSED_PARAM)
{
        if (sap->sa_family == 0xFFFF || sap->sa_family == 0)
                return "[NONE SET]";
        return UNSPEC_print((unsigned char *)sap->sa_data);
}

static const struct aftype unspec_aftype = {
        .name   = "unspec",
        .title  = "UNSPEC",
        .af     = AF_UNSPEC,
        .alen   = 0,
        .print  = UNSPEC_print,
        .sprint = UNSPEC_sprint,
};

static const struct aftype *const aftypes[] = {
        &inet_aftype,
#ifdef HAVE_AFINET6
        &inet6_aftype,
#endif
        &unspec_aftype,
        NULL
};

/* Check our protocol family table for this family. */
const struct aftype* FAST_FUNC get_aftype(const char *name)
{
        const struct aftype *const *afp;

        afp = aftypes;
        while (*afp != NULL) {
                if (strcmp((*afp)->name, name) == 0)
                        return (*afp);
                afp++;
        }
        return NULL;
}

/* Check our protocol family table for this family. */
static const struct aftype *get_afntype(int af)
{
        const struct aftype *const *afp;

        afp = aftypes;
        while (*afp != NULL) {
                if ((*afp)->af == af)
                        return *afp;
                afp++;
        }
        return NULL;
}

struct user_net_device_stats {
        unsigned long long rx_packets;  /* total packets received       */
        unsigned long long tx_packets;  /* total packets transmitted    */
        unsigned long long rx_bytes;    /* total bytes received         */
        unsigned long long tx_bytes;    /* total bytes transmitted      */
        unsigned long rx_errors;        /* bad packets received         */
        unsigned long tx_errors;        /* packet transmit problems     */
        unsigned long rx_dropped;       /* no space in linux buffers    */
        unsigned long tx_dropped;       /* no space available in linux  */
        unsigned long rx_multicast;     /* multicast packets received   */
        unsigned long rx_compressed;
        unsigned long tx_compressed;
        unsigned long collisions;

        /* detailed rx_errors: */
        unsigned long rx_length_errors;
        unsigned long rx_over_errors;   /* receiver ring buff overflow  */
        unsigned long rx_crc_errors;    /* recved pkt with crc error    */
        unsigned long rx_frame_errors;  /* recv'd frame alignment error */
        unsigned long rx_fifo_errors;   /* recv'r fifo overrun          */
        unsigned long rx_missed_errors; /* receiver missed packet     */
        /* detailed tx_errors */
        unsigned long tx_aborted_errors;
        unsigned long tx_carrier_errors;
        unsigned long tx_fifo_errors;
        unsigned long tx_heartbeat_errors;
        unsigned long tx_window_errors;
};

struct interface {
        struct interface *next, *prev;
        char name[IFNAMSIZ];                    /* interface name        */
        short type;                             /* if type               */
        short flags;                            /* various flags         */
        int tx_queue_len;                       /* transmit queue length */

        /* these should be contiguous, zeroed in one go in if_fetch(): */
#define FIRST_TO_ZERO metric
        int metric;                             /* routing metric        */
        int mtu;                                /* MTU value             */
        struct ifmap map;                       /* hardware setup        */
        struct sockaddr addr;                   /* IP address            */
        struct sockaddr dstaddr;                /* P-P IP address        */
        struct sockaddr broadaddr;              /* IP broadcast address  */
        struct sockaddr netmask;                /* IP network mask       */
        char hwaddr[32];                        /* HW address            */
#define LAST_TO_ZERO hwaddr

        smallint has_ip;
        smallint statistics_valid;
        struct user_net_device_stats stats;     /* statistics            */
#if 0 /* UNUSED */
        int keepalive;                          /* keepalive value for SLIP */
        int outfill;                            /* outfill value for SLIP */
#endif
};

struct iface_list {
        struct interface *int_list, *int_last;
};


#if 0
/* like strcmp(), but knows about numbers */
except that the freshly added calls to xatoul() barf on ethernet aliases with
uClibc with e.g.: ife->name='lo'  name='eth0:1'
static int nstrcmp(const char *a, const char *b)
{
        const char *a_ptr = a;
        const char *b_ptr = b;

        while (*a == *b) {
                if (*a == '\0') {
                        return 0;
                }
                if (!isdigit(*a) && isdigit(*(a+1))) {
                        a_ptr = a+1;
                        b_ptr = b+1;
                }
                a++;
                b++;
        }

        if (isdigit(*a) && isdigit(*b)) {
                return xatoul(a_ptr) > xatoul(b_ptr) ? 1 : -1;
        }
        return *a - *b;
}
#endif

static struct interface *add_interface(struct iface_list *ilist, char *name)
{
        struct interface *ife, **nextp, *new;

        for (ife = ilist->int_last; ife; ife = ife->prev) {
                int n = /*n*/strcmp(ife->name, name);

                if (n == 0)
                        return ife;
                if (n < 0)
                        break;
        }

        new = xzalloc(sizeof(*new));
        strncpy_IFNAMSIZ(new->name, name);

        nextp = ife ? &ife->next : &ilist->int_list;
        new->prev = ife;
        new->next = *nextp;
        if (new->next)
                new->next->prev = new;
        else
                ilist->int_last = new;
        *nextp = new;
        return new;
}

static char *get_name(char name[IFNAMSIZ], char *p)
{
        /* Extract NAME from nul-terminated p of the form "<whitespace>NAME:"
         * If match is not made, set NAME to "" and return unchanged p.
         */
        char *nameend;
        char *namestart;

        nameend = namestart = skip_whitespace(p);

        for (;;) {
                if ((nameend - namestart) >= IFNAMSIZ)
                        break; /* interface name too large - return "" */
                if (*nameend == ':') {
                        memcpy(name, namestart, nameend - namestart);
                        name[nameend - namestart] = '\0';
                        return nameend + 1;
                }
                nameend++;
                /* isspace, NUL, any control char? */
                if ((unsigned char)*nameend <= (unsigned char)' ')
                        break; /* trailing ':' not found - return "" */
        }
        name[0] = '\0';
        return p;
}

/* If scanf supports size qualifiers for %n conversions, then we can
 * use a modified fmt that simply stores the position in the fields
 * having no associated fields in the proc string.  Of course, we need
 * to zero them again when we're done.  But that is smaller than the
 * old approach of multiple scanf occurrences with large numbers of
 * args. */

/* static const char *const ss_fmt[] = { */
/*      "%lln%llu%lu%lu%lu%lu%ln%ln%lln%llu%lu%lu%lu%lu%lu", */
/*      "%llu%llu%lu%lu%lu%lu%ln%ln%llu%llu%lu%lu%lu%lu%lu", */
/*      "%llu%llu%lu%lu%lu%lu%lu%lu%llu%llu%lu%lu%lu%lu%lu%lu" */
/* }; */

/* We use %n for unavailable data in older versions of /proc/net/dev formats.
 * This results in bogus stores to ife->FOO members corresponding to
 * %n specifiers (even the size of integers may not match).
 */
#if INT_MAX == LONG_MAX
static const char *const ss_fmt[] = {
        "%n%llu%u%u%u%u%n%n%n%llu%u%u%u%u%u",
        "%llu%llu%u%u%u%u%n%n%llu%llu%u%u%u%u%u",
        "%llu%llu%u%u%u%u%u%u%llu%llu%u%u%u%u%u%u"
};
#else
static const char *const ss_fmt[] = {
        "%n%llu%lu%lu%lu%lu%n%n%n%llu%lu%lu%lu%lu%lu",
        "%llu%llu%lu%lu%lu%lu%n%n%llu%llu%lu%lu%lu%lu%lu",
        "%llu%llu%lu%lu%lu%lu%lu%lu%llu%llu%lu%lu%lu%lu%lu%lu"
};
#endif

static void get_dev_fields(char *bp, struct interface *ife, int procnetdev_vsn)
{
        memset(&ife->stats, 0, sizeof(struct user_net_device_stats));

        sscanf(bp, ss_fmt[procnetdev_vsn],
                   &ife->stats.rx_bytes, /* missing for v0 */
                   &ife->stats.rx_packets,
                   &ife->stats.rx_errors,
                   &ife->stats.rx_dropped,
                   &ife->stats.rx_fifo_errors,
                   &ife->stats.rx_frame_errors,
                   &ife->stats.rx_compressed, /* missing for v0, v1 */
                   &ife->stats.rx_multicast, /* missing for v0, v1 */
                   &ife->stats.tx_bytes, /* missing for v0 */
                   &ife->stats.tx_packets,
                   &ife->stats.tx_errors,
                   &ife->stats.tx_dropped,
                   &ife->stats.tx_fifo_errors,
                   &ife->stats.collisions,
                   &ife->stats.tx_carrier_errors,
                   &ife->stats.tx_compressed /* missing for v0, v1 */
                   );

        if (procnetdev_vsn <= 1) {
                if (procnetdev_vsn == 0) {
                        ife->stats.rx_bytes = 0;
                        ife->stats.tx_bytes = 0;
                }
                ife->stats.rx_multicast = 0;
                ife->stats.rx_compressed = 0;
                ife->stats.tx_compressed = 0;
        }
}

static int procnetdev_version(char *buf)
{
        if (strstr(buf, "compressed"))
                return 2;
        if (strstr(buf, "bytes"))
                return 1;
        return 0;
}

static void if_readconf(struct iface_list *ilist)
{
        int numreqs = 30;
        struct ifconf ifc;
        struct ifreq *ifr;
        int n;
        int skfd;

        ifc.ifc_buf = NULL;

        /* SIOCGIFCONF currently seems to only work properly on AF_INET sockets
           (as of 2.1.128) */
        skfd = xsocket(AF_INET, SOCK_DGRAM, 0);

        for (;;) {
                ifc.ifc_len = sizeof(struct ifreq) * numreqs;
                ifc.ifc_buf = xrealloc(ifc.ifc_buf, ifc.ifc_len);

                xioctl(skfd, SIOCGIFCONF, &ifc);
                if (ifc.ifc_len == (int)(sizeof(struct ifreq) * numreqs)) {
                        /* assume it overflowed and try again */
                        numreqs += 10;
                        continue;
                }
                break;
        }

        ifr = ifc.ifc_req;
        for (n = 0; n < ifc.ifc_len; n += sizeof(struct ifreq)) {
                add_interface(ilist, ifr->ifr_name);
                ifr++;
        }

        close(skfd);
        free(ifc.ifc_buf);
}

static int if_readlist_proc(struct iface_list *ilist, char *ifname)
{
        FILE *fh;
        char buf[512];
        struct interface *ife;
        int procnetdev_vsn;
        int ret;

        fh = fopen_or_warn(_PATH_PROCNET_DEV, "r");
        if (!fh) {
                return 0; /* "not found" */
        }
        fgets(buf, sizeof buf, fh);     /* eat line */
        fgets(buf, sizeof buf, fh);

        procnetdev_vsn = procnetdev_version(buf);

        ret = 0;
        while (fgets(buf, sizeof buf, fh)) {
                char *s, name[IFNAMSIZ];

                s = get_name(name, buf);
                ife = add_interface(ilist, name);
                get_dev_fields(s, ife, procnetdev_vsn);
                ife->statistics_valid = 1;
                if (ifname && strcmp(ifname, name) == 0) {
                        ret = 1; /* found */
                        break;
                }
        }
        fclose(fh);
        return ret;
}

static void if_readlist(struct iface_list *ilist, char *ifname)
{
        int found = if_readlist_proc(ilist, ifname);
        /* Needed in order to get ethN:M aliases */
        if (!found)
                if_readconf(ilist);
}

/* Fetch the interface configuration from the kernel. */
static int if_fetch(struct interface *ife)
{
        struct ifreq ifr;
        char *ifname = ife->name;
        int skfd;

        skfd = xsocket(AF_INET, SOCK_DGRAM, 0);

        strncpy_IFNAMSIZ(ifr.ifr_name, ifname);
        if (ioctl(skfd, SIOCGIFFLAGS, &ifr) < 0) {
                close(skfd);
                return -1;
        }
        ife->flags = ifr.ifr_flags;

        /* set up default values if ioctl's would fail */
        ife->tx_queue_len = -1; /* unknown value */
        memset(&ife->FIRST_TO_ZERO, 0,
                offsetof(struct interface, LAST_TO_ZERO)
                        - offsetof(struct interface, FIRST_TO_ZERO)
                + sizeof(ife->LAST_TO_ZERO)
        );

        strncpy_IFNAMSIZ(ifr.ifr_name, ifname);
        if (ioctl(skfd, SIOCGIFHWADDR, &ifr) >= 0)
                memcpy(ife->hwaddr, ifr.ifr_hwaddr.sa_data, 8);

//er.... why this _isnt_ inside if()?
        ife->type = ifr.ifr_hwaddr.sa_family;

        strncpy_IFNAMSIZ(ifr.ifr_name, ifname);
        if (ioctl(skfd, SIOCGIFMETRIC, &ifr) >= 0)
                ife->metric = ifr.ifr_metric;

        strncpy_IFNAMSIZ(ifr.ifr_name, ifname);
        if (ioctl(skfd, SIOCGIFMTU, &ifr) >= 0)
                ife->mtu = ifr.ifr_mtu;

#ifdef SIOCGIFMAP
        strncpy_IFNAMSIZ(ifr.ifr_name, ifname);
        if (ioctl(skfd, SIOCGIFMAP, &ifr) == 0)
                ife->map = ifr.ifr_map;
#endif

#ifdef HAVE_TXQUEUELEN
        strncpy_IFNAMSIZ(ifr.ifr_name, ifname);
        if (ioctl(skfd, SIOCGIFTXQLEN, &ifr) >= 0)
                ife->tx_queue_len = ifr.ifr_qlen;
#endif

        strncpy_IFNAMSIZ(ifr.ifr_name, ifname);
        ifr.ifr_addr.sa_family = AF_INET;
        if (ioctl(skfd, SIOCGIFADDR, &ifr) == 0) {
                ife->has_ip = 1;
                ife->addr = ifr.ifr_addr;
                strncpy_IFNAMSIZ(ifr.ifr_name, ifname);
                if (ioctl(skfd, SIOCGIFDSTADDR, &ifr) >= 0)
                        ife->dstaddr = ifr.ifr_dstaddr;

                strncpy_IFNAMSIZ(ifr.ifr_name, ifname);
                if (ioctl(skfd, SIOCGIFBRDADDR, &ifr) >= 0)
                        ife->broadaddr = ifr.ifr_broadaddr;

                strncpy_IFNAMSIZ(ifr.ifr_name, ifname);
                if (ioctl(skfd, SIOCGIFNETMASK, &ifr) >= 0)
                        ife->netmask = ifr.ifr_netmask;
        }

        close(skfd);
        return 0;
}

static int do_if_fetch(struct interface *ife)
{
        if (if_fetch(ife) < 0) {
                const char *errmsg;

                if (errno == ENODEV) {
                        /* Give better error message for this case. */
                        errmsg = "Device not found";
                } else {
                        errmsg = strerror(errno);
                }
                bb_error_msg("%s: error fetching interface information: %s",
                                ife->name, errmsg);
                return -1;
        }
        return 0;
}

static const struct hwtype unspec_hwtype = {
        .name =         "unspec",
        .title =        "UNSPEC",
        .type =         -1,
        .print =        UNSPEC_print
};

static const struct hwtype loop_hwtype = {
        .name =         "loop",
        .title =        "Local Loopback",
        .type =         ARPHRD_LOOPBACK
};

/* Display an Ethernet address in readable format. */
static char* FAST_FUNC ether_print(unsigned char *ptr)
{
        char *buff;
        buff = xasprintf("%02X:%02X:%02X:%02X:%02X:%02X",
                ptr[0], ptr[1], ptr[2], ptr[3], ptr[4], ptr[5]
        );
        return auto_string(buff);
}

static const struct hwtype ether_hwtype = {
        .name  = "ether",
        .title = "Ethernet",
        .type  = ARPHRD_ETHER,
        .alen  = ETH_ALEN,
        .print = ether_print,
        .input = in_ether
};

static const struct hwtype ppp_hwtype = {
        .name =         "ppp",
        .title =        "Point-to-Point Protocol",
        .type =         ARPHRD_PPP
};

#if ENABLE_FEATURE_IPV6
static const struct hwtype sit_hwtype = {
        .name =                 "sit",
        .title =                "IPv6-in-IPv4",
        .type =                 ARPHRD_SIT,
        .print =                UNSPEC_print,
        .suppress_null_addr =   1
};
#endif
#if ENABLE_FEATURE_HWIB
static const struct hwtype ib_hwtype = {
        .name  = "infiniband",
        .title = "InfiniBand",
        .type  = ARPHRD_INFINIBAND,
        .alen  = INFINIBAND_ALEN,
        .print = UNSPEC_print,
        .input = in_ib,
};
#endif


static const struct hwtype *const hwtypes[] = {
        &loop_hwtype,
        &ether_hwtype,
        &ppp_hwtype,
        &unspec_hwtype,
#if ENABLE_FEATURE_IPV6
        &sit_hwtype,
#endif
#if ENABLE_FEATURE_HWIB
        &ib_hwtype,
#endif
        NULL
};

#ifdef IFF_PORTSEL
static const char *const if_port_text[] ALIGN_PTR = {
        /* Keep in step with <linux/netdevice.h> */
        "unknown",
        "10base2",
        "10baseT",
        "AUI",
        "100baseT",
        "100baseTX",
        "100baseFX",
        NULL
};
#endif

/* Check our hardware type table for this type. */
const struct hwtype* FAST_FUNC get_hwtype(const char *name)
{
        const struct hwtype *const *hwp;

        hwp = hwtypes;
        while (*hwp != NULL) {
                if (strcmp((*hwp)->name, name) == 0)
                        return (*hwp);
                hwp++;
        }
        return NULL;
}

/* Check our hardware type table for this type. */
const struct hwtype* FAST_FUNC get_hwntype(int type)
{
        const struct hwtype *const *hwp;

        hwp = hwtypes;
        while (*hwp != NULL) {
                if ((*hwp)->type == type)
                        return *hwp;
                hwp++;
        }
        return NULL;
}

/* return 1 if address is all zeros */
static int hw_null_address(const struct hwtype *hw, void *ap)
{
        int i;
        unsigned char *address = (unsigned char *) ap;

        for (i = 0; i < hw->alen; i++)
                if (address[i])
                        return 0;
        return 1;
}

static const char TRext[] ALIGN1 = "\0\0\0Ki\0Mi\0Gi\0Ti";

static void print_bytes_scaled(unsigned long long ull, const char *end)
{
        unsigned long long int_part;
        const char *ext;
        unsigned int frac_part;
        int i;

        frac_part = 0;
        ext = TRext;
        int_part = ull;
        i = 4;
        do {
                if (int_part >= 1024) {
                        frac_part = ((((unsigned int) int_part) & (1024-1)) * 10) / 1024;
                        int_part /= 1024;
                        ext += 3;       /* KiB, MiB, GiB, TiB */
                }
                --i;
        } while (i);

        printf("X bytes:%llu (%llu.%u %sB)%s", ull, int_part, frac_part, ext, end);
}


#ifdef HAVE_AFINET6
#define IPV6_ADDR_ANY           0x0000U

#define IPV6_ADDR_UNICAST       0x0001U
#define IPV6_ADDR_MULTICAST     0x0002U
#define IPV6_ADDR_ANYCAST       0x0004U

#define IPV6_ADDR_LOOPBACK      0x0010U
#define IPV6_ADDR_LINKLOCAL     0x0020U
#define IPV6_ADDR_SITELOCAL     0x0040U

#define IPV6_ADDR_COMPATv4      0x0080U

#define IPV6_ADDR_SCOPE_MASK    0x00f0U

#define IPV6_ADDR_MAPPED        0x1000U
#define IPV6_ADDR_RESERVED      0x2000U /* reserved address space */


static void ife_print6(struct interface *ptr)
{
        FILE *f;
        char addr6[40], devname[21];
        struct sockaddr_in6 sap;
        int plen, scope, dad_status, if_idx;
        char addr6p[8][5];

        f = fopen_for_read(_PATH_PROCNET_IFINET6);
        if (f == NULL)
                return;

        while (fscanf
                   (f, "%4s%4s%4s%4s%4s%4s%4s%4s %08x %02x %02x %02x %20s\n",
                        addr6p[0], addr6p[1], addr6p[2], addr6p[3], addr6p[4],
                        addr6p[5], addr6p[6], addr6p[7], &if_idx, &plen, &scope,
                        &dad_status, devname) != EOF
        ) {
                if (strcmp(devname, ptr->name) == 0) {
                        sprintf(addr6, "%s:%s:%s:%s:%s:%s:%s:%s",
                                        addr6p[0], addr6p[1], addr6p[2], addr6p[3],
                                        addr6p[4], addr6p[5], addr6p[6], addr6p[7]);
                        memset(&sap, 0, sizeof(sap));
                        inet_pton(AF_INET6, addr6,
                                          (struct sockaddr *) &sap.sin6_addr);
                        sap.sin6_family = AF_INET6;
                        printf("          inet6 addr: %s/%d",
                                INET6_sprint((struct sockaddr *) &sap, 1),
                                plen);
                        printf(" Scope:");
                        switch (scope & IPV6_ADDR_SCOPE_MASK) {
                        case 0:
                                puts("Global");
                                break;
                        case IPV6_ADDR_LINKLOCAL:
                                puts("Link");
                                break;
                        case IPV6_ADDR_SITELOCAL:
                                puts("Site");
                                break;
                        case IPV6_ADDR_COMPATv4:
                                puts("Compat");
                                break;
                        case IPV6_ADDR_LOOPBACK:
                                puts("Host");
                                break;
                        default:
                                puts("Unknown");
                        }
                }
        }
        fclose(f);
}
#else
#define ife_print6(a) ((void)0)
#endif

static void ife_print(struct interface *ptr)
{
        const struct aftype *ap;
        const struct hwtype *hw;
        int hf;
        int can_compress = 0;

        ap = get_afntype(ptr->addr.sa_family);
        if (ap == NULL)
                ap = get_afntype(0);

        hf = ptr->type;

        if (hf == ARPHRD_CSLIP || hf == ARPHRD_CSLIP6)
                can_compress = 1;

        hw = get_hwntype(hf);
        if (hw == NULL)
                hw = get_hwntype(-1);

        printf("%-9s Link encap:%s  ", ptr->name, hw->title);
        /* For some hardware types (eg Ash, ATM) we don't print the
           hardware address if it's null.  */
        if (hw->print != NULL
         && !(hw_null_address(hw, ptr->hwaddr) && hw->suppress_null_addr)
        ) {
                printf("HWaddr %s  ", hw->print((unsigned char *)ptr->hwaddr));
        }
#ifdef IFF_PORTSEL
        if (ptr->flags & IFF_PORTSEL) {
                printf("Media:%s", if_port_text[ptr->map.port] /* [0] */);
                if (ptr->flags & IFF_AUTOMEDIA)
                        printf("(auto)");
        }
#endif
        bb_putchar('\n');

        if (ptr->has_ip) {
                printf("          %s addr:%s ", ap->name,
                        ap->sprint(&ptr->addr, 1));
                if (ptr->flags & IFF_POINTOPOINT) {
                        printf(" P-t-P:%s ", ap->sprint(&ptr->dstaddr, 1));
                }
                if (ptr->flags & IFF_BROADCAST) {
                        printf(" Bcast:%s ", ap->sprint(&ptr->broadaddr, 1));
                }
                printf(" Mask:%s\n", ap->sprint(&ptr->netmask, 1));
        }

        ife_print6(ptr);

        printf("          ");
        /* DONT FORGET TO ADD THE FLAGS IN ife_print_short, too */

        if (ptr->flags == 0) {
                printf("[NO FLAGS] ");
        } else {
                static const char ife_print_flags_strs[] ALIGN1 =
                        "UP\0"
                        "BROADCAST\0"
                        "DEBUG\0"
                        "LOOPBACK\0"
                        "POINTOPOINT\0"
                        "NOTRAILERS\0"
                        "RUNNING\0"
                        "NOARP\0"
                        "PROMISC\0"
                        "ALLMULTI\0"
                        "SLAVE\0"
                        "MASTER\0"
                        "MULTICAST\0"
#ifdef HAVE_DYNAMIC
                        "DYNAMIC\0"
#endif
                        ;
                static const unsigned short ife_print_flags_mask[] ALIGN2 = {
                        IFF_UP,
                        IFF_BROADCAST,
                        IFF_DEBUG,
                        IFF_LOOPBACK,
                        IFF_POINTOPOINT,
                        IFF_NOTRAILERS,
                        IFF_RUNNING,
                        IFF_NOARP,
                        IFF_PROMISC,
                        IFF_ALLMULTI,
                        IFF_SLAVE,
                        IFF_MASTER,
                        IFF_MULTICAST
#ifdef HAVE_DYNAMIC
                        ,IFF_DYNAMIC
#endif
                };
                const unsigned short *mask = ife_print_flags_mask;
                const char *str = ife_print_flags_strs;
                do {
                        if (ptr->flags & *mask) {

                                printf("%s ", str);
                        }
                        mask++;
                        str += strlen(str) + 1;
                } while (*str);
        }

        /* DONT FORGET TO ADD THE FLAGS IN ife_print_short */
        printf(" MTU:%d  Metric:%d", ptr->mtu, ptr->metric ? ptr->metric : 1);
#if 0
#ifdef SIOCSKEEPALIVE
        if (ptr->outfill || ptr->keepalive)
                printf("  Outfill:%d  Keepalive:%d", ptr->outfill, ptr->keepalive);
#endif
#endif
        bb_putchar('\n');

        /* If needed, display the interface statistics. */

        if (ptr->statistics_valid) {
                /* XXX: statistics are currently only printed for the primary address,
                 *      not for the aliases, although strictly speaking they're shared
                 *      by all addresses.
                 */
                printf("          ");

                printf("RX packets:%llu errors:%lu dropped:%lu overruns:%lu frame:%lu\n",
                        ptr->stats.rx_packets, ptr->stats.rx_errors,
                        ptr->stats.rx_dropped, ptr->stats.rx_fifo_errors,
                        ptr->stats.rx_frame_errors);
                if (can_compress)
                        printf("             compressed:%lu\n",
                                ptr->stats.rx_compressed);
                printf("          ");
                printf("TX packets:%llu errors:%lu dropped:%lu overruns:%lu carrier:%lu\n",
                        ptr->stats.tx_packets, ptr->stats.tx_errors,
                        ptr->stats.tx_dropped, ptr->stats.tx_fifo_errors,
                        ptr->stats.tx_carrier_errors);
                printf("          collisions:%lu ", ptr->stats.collisions);
                if (can_compress)
                        printf("compressed:%lu ", ptr->stats.tx_compressed);
                if (ptr->tx_queue_len != -1)
                        printf("txqueuelen:%d ", ptr->tx_queue_len);
                printf("\n          R");
                print_bytes_scaled(ptr->stats.rx_bytes, "  T");
                print_bytes_scaled(ptr->stats.tx_bytes, "\n");
        }

        if (ptr->map.irq || ptr->map.mem_start
         || ptr->map.dma || ptr->map.base_addr
        ) {
                printf("          ");
                if (ptr->map.irq)
                        printf("Interrupt:%d ", ptr->map.irq);
                if (ptr->map.base_addr >= 0x100) /* Only print devices using it for I/O maps */
                        printf("Base address:0x%lx ",
                                (unsigned long) ptr->map.base_addr);
                if (ptr->map.mem_start) {
                        printf("Memory:%lx-%lx ", ptr->map.mem_start,
                                ptr->map.mem_end);
                }
                if (ptr->map.dma)
                        printf("DMA chan:%x ", ptr->map.dma);
                bb_putchar('\n');
        }
        bb_putchar('\n');
}

static int do_if_print(struct interface *ife, int show_downed_too)
{
        int res;

        res = do_if_fetch(ife);
        if (res >= 0) {
                if ((ife->flags & IFF_UP) || show_downed_too)
                        ife_print(ife);
        }
        return res;
}

int FAST_FUNC display_interfaces(char *ifname)
{
        struct interface *ife;
        int res;
        struct iface_list ilist;

        ilist.int_list = NULL;
        ilist.int_last = NULL;
        if_readlist(&ilist, ifname != IFNAME_SHOW_DOWNED_TOO ? ifname : NULL);

        if (!ifname || ifname == IFNAME_SHOW_DOWNED_TOO) {
                for (ife = ilist.int_list; ife; ife = ife->next) {

                        BUILD_BUG_ON((int)(intptr_t)IFNAME_SHOW_DOWNED_TOO != 1);

                        res = do_if_print(ife, (int)(intptr_t)ifname);
                        if (res < 0)
                                goto ret;
                }
                return 0;
        }

        ife = add_interface(&ilist, ifname);
        res = do_if_print(ife, /*show_downed_too:*/ 1);
 ret:
        return (res < 0); /* status < 0 == 1 -- error */
}

#if ENABLE_FEATURE_HWIB
/* Input an Infiniband address and convert to binary. */
int FAST_FUNC in_ib(const char *bufp, struct sockaddr *sap)
{
        sap->sa_family = ib_hwtype.type;
//TODO: error check?
        hex2bin((char*)sap->sa_data, bufp, INFINIBAND_ALEN);
# ifdef HWIB_DEBUG
        fprintf(stderr, "in_ib(%s): %s\n", bufp, UNSPEC_print(sap->sa_data));
# endif
        return 0;
}
#endif