interface_linux.c

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}

/*
 *
 * @retval  0 success
 * @retval -1 no container specified
 * @retval -2 could not open /proc/net/dev
 * @retval -3 could not create entry (probably malloc)
 */
int
netsnmp_arch_interface_container_load(netsnmp_container* container,
                                      u_int load_flags)
{
    FILE           *devin;
    char            line[256];
    netsnmp_interface_entry *entry = NULL;
    static char     scan_expected = 0;
    int             fd;
#ifdef NETSNMP_ENABLE_IPV6
    netsnmp_container *addr_container;
#endif

    DEBUGMSGTL(("access:interface:container:arch", "load (flags %p)\n",
                load_flags));

    if (NULL == container) {
        snmp_log(LOG_ERR, "no container specified/found for interface\n");
        return -1;
    }

    if (!(devin = fopen("/proc/net/dev", "r"))) {
        DEBUGMSGTL(("access:interface",
                    "Failed to load Interface Table (linux1)\n"));
        snmp_log(LOG_ERR, "cannot open /proc/net/dev ...\n");
        return -2;
    }

    /*
     * create socket for ioctls
     */
    fd = socket(AF_INET, SOCK_DGRAM, 0);
    if(fd < 0) {
        snmp_log(LOG_ERR, "could not create socket\n");
        return -2;
    }

#ifdef NETSNMP_ENABLE_IPV6
    /*
     * get ipv6 addresses
     */
    addr_container = netsnmp_access_ipaddress_container_load(NULL, 0);
#endif

    /*
     * Read the first two lines of the file, containing the header
     * This indicates which version of the kernel we're working with,
     * and hence which statistics are actually available.
     *
     * Wes originally suggested parsing the field names in this header
     * to detect the position of individual fields directly,
     * but I suspect this is probably more trouble than it's worth.
     */
    fgets(line, sizeof(line), devin);
    fgets(line, sizeof(line), devin);

    if( 0 == scan_expected ) {
        if (strstr(line, "compressed")) {
            scan_expected = 10;
            DEBUGMSGTL(("access:interface",
                        "using linux 2.2 kernel /proc/net/dev\n"));
        } else {
            scan_expected = 5;
            DEBUGMSGTL(("access:interface",
                        "using linux 2.0 kernel /proc/net/dev\n"));
        }
    }

    /*
     * The rest of the file provides the statistics for each interface.
     * Read in each line in turn, isolate the interface name
     *   and retrieve (or create) the corresponding data structure.
     */
    while (fgets(line, sizeof(line), devin)) {
        char           *stats, *ifstart = line;
        u_int           flags;
        oid             if_index;

        flags = 0;
        if (line[strlen(line) - 1] == '\n')
            line[strlen(line) - 1] = '\0';

        while (*ifstart && *ifstart == ' ')
            ifstart++;

        if ((!*ifstart) || ((stats = strrchr(ifstart, ':')) == NULL)) {
            snmp_log(LOG_ERR,
                     "interface data format error 1, line ==|%s|\n", line);
            continue;
        }
        if ((scan_expected == 10) && ((stats - line) < 6)) {
            snmp_log(LOG_ERR,
                     "interface data format error 2 (%d < 6), line ==|%s|\n",
                     stats - line, line);
        }

        DEBUGMSGTL(("9:access:ifcontainer", "processing '%s'\n", ifstart));

        /*
         * get index via ioctl.
         * If we've met this interface before, use the same index.
         * Otherwise find an unused index value and use that.
         */
        *stats++ = 0; /* null terminate name */

        if_index = netsnmp_arch_interface_index_find(ifstart);

        /*
         * set address type flags.
         * the only way I know of to check an interface for
         * ip version is to look for ip addresses. If anyone
         * knows a better way, put it here!
         */
#ifdef NETSNMP_ENABLE_IPV6
        _arch_interface_has_ipv6(if_index, &flags, addr_container);
#endif
        netsnmp_access_interface_ioctl_has_ipv4(fd, ifstart, 0, &flags);

        /*
         * do we only want one address type?
         */
        if (((load_flags & NETSNMP_ACCESS_INTERFACE_LOAD_IP4_ONLY) &&
             ((flags & NETSNMP_INTERFACE_FLAGS_HAS_IPV4) == 0)) ||
            ((load_flags & NETSNMP_ACCESS_INTERFACE_LOAD_IP6_ONLY) &&
             ((flags & NETSNMP_INTERFACE_FLAGS_HAS_IPV6) == 0))) {
            DEBUGMSGTL(("9:access:ifcontainer",
                        "interface '%s' excluded by ip version\n",
                        ifstart));
            continue;
        }

        entry = netsnmp_access_interface_entry_create(ifstart, 0);
        if(NULL == entry) {
#ifdef NETSNMP_ENABLE_IPV6
            netsnmp_access_ipaddress_container_free(addr_container, 0);
#endif
            netsnmp_access_interface_container_free(container,
                                                    NETSNMP_ACCESS_INTERFACE_FREE_NOFLAGS);
            fclose(devin);
            close(fd);
            return -3;
        }
        entry->ns_flags = flags; /* initial flags; we'll set more later */

        /*
         * xxx-rks: get descr by linking mem from /proc/pci and /proc/iomem
         */


        /*
         * use ioctls for some stuff
         *  (ignore rc, so we get as much info as possible)
         */
        netsnmp_access_interface_ioctl_physaddr_get(fd, entry);

        /*
         * physaddr should have set type. make some guesses (based
         * on name) if not.
         */
        if(0 == entry->type) {
            typedef struct _match_if {
               int             mi_type;
               const char     *mi_name;
            }              *pmatch_if, match_if;
            
            static match_if lmatch_if[] = {
                {IANAIFTYPE_SOFTWARELOOPBACK, "lo"},
                {IANAIFTYPE_ETHERNETCSMACD, "eth"},
                {IANAIFTYPE_ETHERNETCSMACD, "vmnet"},
                {IANAIFTYPE_ISO88025TOKENRING, "tr"},
                {IANAIFTYPE_FASTETHER, "feth"},
                {IANAIFTYPE_GIGABITETHERNET,"gig"},
                {IANAIFTYPE_PPP, "ppp"},
                {IANAIFTYPE_SLIP, "sl"},
                {IANAIFTYPE_TUNNEL, "sit"},
                {IANAIFTYPE_BASICISDN, "ippp"},
                {IANAIFTYPE_PROPVIRTUAL, "bond"}, /* Bonding driver find fastest slave */
                {IANAIFTYPE_PROPVIRTUAL, "vad"},  /* ANS driver - ?speed? */
                {0, 0}                  /* end of list */
            };

            int             ii, len;
            register pmatch_if pm;
            
            for (ii = 0, pm = lmatch_if; pm->mi_name; pm++) {
                len = strlen(pm->mi_name);
                if (0 == strncmp(entry->name, pm->mi_name, len)) {
                    entry->type = pm->mi_type;
                    break;
                }
            }
            if(NULL == pm->mi_name)
                entry->type = IANAIFTYPE_OTHER;
        }

        if (IANAIFTYPE_ETHERNETCSMACD == entry->type)
            entry->speed =
                netsnmp_linux_interface_get_if_speed(fd, entry->name);
#ifdef APPLIED_PATCH_836390   /* xxx-rks ifspeed fixes */
        else if (IANAIFTYPE_PROPVIRTUAL == entry->type)
            entry->speed = _get_bonded_if_speed(entry);
#endif
        else
            netsnmp_access_interface_entry_guess_speed(entry);
        
        netsnmp_access_interface_ioctl_flags_get(fd, entry);

        netsnmp_access_interface_ioctl_mtu_get(fd, entry);

        /*
         * Zero speed means link problem.
         * - i'm not sure this is always true...
         */
        if((entry->speed == 0) && (entry->os_flags & IFF_UP)) {
            entry->os_flags &= ~IFF_RUNNING;
        }

        /*
         * check for promiscuous mode.
         *  NOTE: there are 2 ways to set promiscuous mode in Linux
         *  (kernels later than 2.2.something) - using ioctls and
         *  using setsockopt. The ioctl method tested here does not
         *  detect if an interface was set using setsockopt. google
         *  on IFF_PROMISC and linux to see lots of arguments about it.
         */
        if(entry->os_flags & IFF_PROMISC) {
            entry->promiscuous = 1; /* boolean */
        }

        /*
         * hardcoded max packet size
         * (see ip_frag_reasm: if(len > 65535) goto out_oversize;)
         */
        entry->reasm_max_v4 = entry->reasm_max_v6 = 65535;
        entry->ns_flags |= 
            NETSNMP_INTERFACE_FLAGS_HAS_V4_REASMMAX |
            NETSNMP_INTERFACE_FLAGS_HAS_V6_REASMMAX;

        netsnmp_access_interface_entry_overrides(entry);

        entry->speed_high = entry->speed / 1000000;

        if (! (load_flags & NETSNMP_ACCESS_INTERFACE_LOAD_NO_STATS))
            _parse_stats(entry, stats, scan_expected);

        if (flags & NETSNMP_INTERFACE_FLAGS_HAS_IPV4)
            _arch_interface_flags_v4_get(entry);

#ifdef NETSNMP_ENABLE_IPV6
        if (flags & NETSNMP_INTERFACE_FLAGS_HAS_IPV6)
            _arch_interface_flags_v6_get(entry);
#endif /* NETSNMP_ENABLE_IPV6 */

        /*
         * add to container
         */
        CONTAINER_INSERT(container, entry);
    }
#ifdef NETSNMP_ENABLE_IPV6
    netsnmp_access_ipaddress_container_free(addr_container, 0);
#endif
    fclose(devin);
    close(fd);
    return 0;
}

int
netsnmp_arch_set_admin_status(netsnmp_interface_entry * entry,
                              int ifAdminStatus_val)
{
    int and_complement;
    
    DEBUGMSGTL(("access:interface:arch", "set_admin_status\n"));

    if(IFADMINSTATUS_UP == ifAdminStatus_val)
        and_complement = 0; /* |= */
    else
        and_complement = 1; /* &= ~ */

    return netsnmp_access_interface_ioctl_flags_set(-1, entry,
                                                    IFF_UP, and_complement);
}

#ifdef HAVE_LINUX_ETHTOOL_H
/**
 * Determines network interface speed from ETHTOOL_GSET
 */
unsigned int
netsnmp_linux_interface_get_if_speed(int fd, const char *name)
{
    struct ifreq ifr;
    struct ethtool_cmd edata;

    memset(&ifr, 0, sizeof(ifr));
    edata.cmd = ETHTOOL_GSET;
    
    strncpy(ifr.ifr_name, name, sizeof(ifr.ifr_name)-1);
    ifr.ifr_data = (char *) &edata;
    
    if (ioctl(fd, SIOCETHTOOL, &ifr) == -1) {
        DEBUGMSGTL(("mibII/interfaces", "ETHTOOL_GSET on %s failed\n",
                    ifr.ifr_name));
        return netsnmp_linux_interface_get_if_speed_mii(fd,name);
    }
    
    if (edata.speed != SPEED_10 && edata.speed != SPEED_100 &&
        edata.speed != SPEED_1000) {
        DEBUGMSGTL(("mibII/interfaces", "fallback to mii for %s\n",
                    ifr.ifr_name));
        /* try MII */
        return netsnmp_linux_interface_get_if_speed_mii(fd,name);
    }

    /* return in bps */
    DEBUGMSGTL(("mibII/interfaces", "ETHTOOL_GSET on %s speed = %d\n",
                ifr.ifr_name, edata.speed));
    return edata.speed*1000*1000;
}
#endif
 
/**
 * Determines network interface speed from MII
 */
unsigned int
#ifdef HAVE_LINUX_ETHTOOL_H
netsnmp_linux_interface_get_if_speed_mii(int fd, const char *name)
#else
netsnmp_linux_interface_get_if_speed(int fd, const char *name)
#endif
{
    unsigned int retspeed = 10000000;
    struct ifreq ifr;

    /* the code is based on mii-diag utility by Donald Becker
     * see ftp://ftp.scyld.com/pub/diag/mii-diag.c
     */
    ushort *data = (ushort *)(&ifr.ifr_data);
    unsigned phy_id;
    unsigned char new_ioctl_nums = 0;
    int mii_reg, i;
    ushort mii_val[32];
    ushort bmcr, bmsr, nway_advert, lkpar;
    const unsigned int media_speeds[] = {10000000, 10000000, 100000000, 100000000, 10000000, 0};	
    /* It corresponds to "10baseT", "10baseT-FD", "100baseTx", "100baseTx-FD", "100baseT4", "Flow-control", 0, */

    strncpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
    ifr.ifr_name[ sizeof(ifr.ifr_name)-1 ] = 0;
    data[0] = 0;
    
    if (ioctl(fd, 0x8947, &ifr) >= 0) {
        new_ioctl_nums = 1;
    } else if (ioctl(fd, SIOCDEVPRIVATE, &ifr) >= 0) {
        new_ioctl_nums = 0;
    } else {
        DEBUGMSGTL(("mibII/interfaces", "SIOCGMIIPHY on %s failed\n",
                    ifr.ifr_name));
        return retspeed;
    }

    /* Begin getting mii register values */
    phy_id = data[0];
    for (mii_reg = 0; mii_reg < 8; mii_reg++){
        data[0] = phy_id;
        data[1] = mii_reg;
        if(ioctl(fd, new_ioctl_nums ? 0x8948 : SIOCDEVPRIVATE+1, &ifr) <0){
            DEBUGMSGTL(("mibII/interfaces", "SIOCGMIIREG on %s failed\n", ifr.ifr_name));
        }
        mii_val[mii_reg] = data[3];		
    }
    /*Parsing of mii values*/
    /*Invalid basic mode control register*/
    if (mii_val[0] == 0xffff  ||  mii_val[1] == 0x0000) {
        DEBUGMSGTL(("mibII/interfaces", "No MII transceiver present!.\n"));
        return retspeed;
    }
    /* Descriptive rename. */
    bmcr = mii_val[0]; 	  /*basic mode control register*/
    bmsr = mii_val[1]; 	  /* basic mode status register*/
    nway_advert = mii_val[4]; /* autonegotiation advertisement*/
    lkpar = mii_val[5]; 	  /*link partner ability*/
    
    /*Check for link existence, returns 0 if link is absent*/
    if ((bmsr & 0x0016) != 0x0004){
        DEBUGMSGTL(("mibII/interfaces", "No link...\n"));
        retspeed = 0;
        return retspeed;
    }
    
    if(!(bmcr & 0x1000) ){
        DEBUGMSGTL(("mibII/interfaces", "Auto-negotiation disabled.\n"));
        retspeed = bmcr & 0x2000 ? 100000000 : 10000000;
        return retspeed;
    }
    /* Link partner got our advertised abilities */	
    if (lkpar & 0x4000) {
        int negotiated = nway_advert & lkpar & 0x3e0;
        int max_capability = 0;
        /* Scan for the highest negotiated capability, highest priority
           (100baseTx-FDX) to lowest (10baseT-HDX). */
        int media_priority[] = {8, 9, 7, 6, 5}; 	/* media_names[i-5] */
        for (i = 0; media_priority[i]; i++){
            if (negotiated & (1 << media_priority[i])) {
                max_capability = media_priority[i];
                break;
            }
        }
        if (max_capability)
            retspeed = media_speeds[max_capability - 5];
        else
            DEBUGMSGTL(("mibII/interfaces", "No common media type was autonegotiated!\n"));
    }else if(lkpar & 0x00A0){
        retspeed = (lkpar & 0x0080) ? 100000000 : 10000000;
    }
    return retspeed;
}