link.c

/*
 * lib/route/link.c     Links (Interfaces)
 *
 *      This library is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU Lesser General Public
 *      License as published by the Free Software Foundation version 2.1
 *      of the License.
 *
 * Copyright (c) 2003-2006 Thomas Graf <tgraf@suug.ch>
 */
 
/**
 * @ingroup rtnl
 * @defgroup link Links (Interfaces)
 * @brief
 *
 * @par Link Identification
 * A link can be identified by either its interface index or by its
 * name. The kernel favours the interface index but falls back to the
 * interface name if the interface index is lesser-than 0 for kernels
 * >= 2.6.11. Therefore you can request changes without mapping a
 * interface name to the corresponding index first.
 *
 * @par Changeable Attributes
 * @anchor link_changeable
 *  - Link layer address
 *  - Link layer broadcast address
 *  - device mapping (ifmap) (>= 2.6.9)
 *  - MTU (>= 2.6.9)
 *  - Transmission queue length (>= 2.6.9)
 *  - Weight (>= 2.6.9)
 *  - Link name (only via access through interface index) (>= 2.6.9)
 *  - Flags (>= 2.6.9)
 *    - IFF_DEBUG
 *    - IFF_NOTRAILERS
 *    - IFF_NOARP
 *    - IFF_DYNAMIC
 *    - IFF_MULTICAST
 *    - IFF_PORTSEL
 *    - IFF_AUTOMEDIA
 *    - IFF_UP
 *    - IFF_PROMISC
 *    - IFF_ALLMULTI
 *
 * @par Link Flags (linux/if.h)
 * @anchor link_flags
 * @code
 *   IFF_UP            Status of link (up|down)
 *   IFF_BROADCAST     Indicates this link allows broadcasting
 *   IFF_MULTICAST     Indicates this link allows multicasting
 *   IFF_ALLMULTI      Indicates this link is doing multicast routing
 *   IFF_DEBUG         Tell the driver to do debugging (currently unused)
 *   IFF_LOOPBACK      This is the loopback link
 *   IFF_POINTOPOINT   Point-to-point link
 *   IFF_NOARP         Link is unable to perform ARP
 *   IFF_PROMISC       Status of promiscious mode flag
 *   IFF_MASTER        Used by teql
 *   IFF_SLAVE         Used by teql
 *   IFF_PORTSEL       Indicates this link allows port selection
 *   IFF_AUTOMEDIA     Indicates this link selects port automatically
 *   IFF_DYNAMIC       Indicates the address of this link is dynamic
 *   IFF_RUNNING       Link is running and carrier is ok.
 *   IFF_NOTRAILERS    Unused, BSD compat.
 * @endcode
 *
 * @par Notes on IFF_PROMISC and IFF_ALLMULTI flags
 * Although you can query the status of IFF_PROMISC and IFF_ALLMULTI
 * they do not represent the actual state in the kernel but rather
 * whether the flag has been enabled/disabled by userspace. The link
 * may be in promiscious mode even if IFF_PROMISC is not set in a link
 * dump request response because promiscity might be needed by the driver
 * for a period of time.
 *
 * @note The unit of the transmission queue length depends on the
 *       link type, a common unit is \a packets.
 *
 * @par 1) Retrieving information about available links
 * @code
 * // The first step is to retrieve a list of all available interfaces within
 * // the kernel and put them into a cache.
 * struct nl_cache *cache = rtnl_link_alloc_cache(nl_handle);
 *
 * // In a second step, a specific link may be looked up by either interface
 * // index or interface name.
 * struct rtnl_link *link = rtnl_link_get_by_name(cache, "lo");
 *
 * // rtnl_link_get_by_name() is the short version for translating the
 * // interface name to an interface index first like this:
 * int ifindex = rtnl_link_name2i(cache, "lo");
 * struct rtnl_link *link = rtnl_link_get(cache, ifindex);
 *
 * // After successful usage, the object must be given back to the cache
 * rtnl_link_put(link);
 * @endcode
 *
 * @par 2) Changing link attributes
 * @code
 * // In order to change any attributes of an existing link, we must allocate
 * // a new link to hold the change requests:
 * struct rtnl_link *request = rtnl_link_alloc();
 *
 * // Now we can go on and specify the attributes we want to change:
 * rtnl_link_set_weight(request, 300);
 * rtnl_link_set_mtu(request, 1360);
 *
 * // We can also shut an interface down administratively
 * rtnl_link_unset_flags(request, rtnl_link_str2flags("up"));
 *
 * // Actually, we should know which link to change, so let's look it up
 * struct rtnl_link *old = rtnl_link_get(cache, "eth0");
 *
 * // Two ways exist to commit this change request, the first one is to
 * // build the required netlink message and send it out in one single
 * // step:
 * rtnl_link_change(nl_handle, old, request);
 *
 * // An alternative way is to build the netlink message and send it
 * // out yourself using nl_send_auto_complete()
 * struct nl_msg *msg = rtnl_link_build_change_request(old, request);
 * nl_send_auto_complete(nl_handle, nlmsg_hdr(msg));
 * nlmsg_free(msg);
 *
 * // Don't forget to give back the link object ;->
 * rtnl_link_put(old);
 * @endcode
 *
 * @par 3) Link Type Specific Attributes
 * @code
 * // Some link types offer additional parameters and statistics specific
 * // to their type. F.e. a VLAN link can be configured like this:
 * //
 * // Allocate a new link and set the info type to "vlan". This is required
 * // to prepare the link to hold vlan specific attributes.
 * struct rtnl_link *request = rtnl_link_alloc();
 * rtnl_link_set_info_type(request, "vlan");
 *
 * // Now vlan specific attributes can be set:
 * rtnl_link_vlan_set_id(request, 10);
 * rtnl_link_vlan_set_ingress_map(request, 2, 8);
 *
 * // Of course the attributes can also be read, check the info type
 * // to make sure you are using the right access functions:
 * char *type = rtnl_link_get_info_type(link);
 * if (!strcmp(type, "vlan"))
 *      int id = rtnl_link_vlan_get_id(link);
 * @endcode
 * @{
 */
 
#include <netlink-local.h>
#include <netlink/netlink.h>
#include <netlink/attr.h>
#include <netlink/utils.h>
#include <netlink/object.h>
#include <netlink/route/rtnl.h>
#include <netlink/route/link.h>
#include <netlink/route/link/info-api.h>
 
/** @cond SKIP */
#define LINK_ATTR_MTU     0x0001
#define LINK_ATTR_LINK    0x0002
#define LINK_ATTR_TXQLEN  0x0004
#define LINK_ATTR_WEIGHT  0x0008
#define LINK_ATTR_MASTER  0x0010
#define LINK_ATTR_QDISC   0x0020
#define LINK_ATTR_MAP     0x0040
#define LINK_ATTR_ADDR    0x0080
#define LINK_ATTR_BRD     0x0100
#define LINK_ATTR_FLAGS   0x0200
#define LINK_ATTR_IFNAME  0x0400
#define LINK_ATTR_IFINDEX 0x0800
#define LINK_ATTR_FAMILY  0x1000
#define LINK_ATTR_ARPTYPE 0x2000
#define LINK_ATTR_STATS   0x4000
#define LINK_ATTR_CHANGE  0x8000
#define LINK_ATTR_OPERSTATE 0x10000
#define LINK_ATTR_LINKMODE  0x20000
#define LINK_ATTR_LINKINFO  0x40000
 
static struct nl_cache_ops rtnl_link_ops;
static struct nl_object_ops link_obj_ops;
/** @endcond */
 
static void release_link_info(struct rtnl_link *link)
{
        struct rtnl_link_info_ops *io = link->l_info_ops;
 
        if (io != NULL) {
                io->io_refcnt--;
                io->io_free(link);
                link->l_info_ops = NULL;
        }
}
 
static void link_free_data(struct nl_object *c)
{
        struct rtnl_link *link = nl_object_priv(c);
 
        if (link) {
                struct rtnl_link_info_ops *io;
 
                if ((io = link->l_info_ops) != NULL)
                        release_link_info(link);
 
                nl_addr_put(link->l_addr);
                nl_addr_put(link->l_bcast);
        }
}
 
static int link_clone(struct nl_object *_dst, struct nl_object *_src)
{
        struct rtnl_link *dst = nl_object_priv(_dst);
        struct rtnl_link *src = nl_object_priv(_src);
        int err;
 
        if (src->l_addr)
                if (!(dst->l_addr = nl_addr_clone(src->l_addr)))
                        goto errout;
 
        if (src->l_bcast)
                if (!(dst->l_bcast = nl_addr_clone(src->l_bcast)))
                        goto errout;
 
        if (src->l_info_ops && src->l_info_ops->io_clone) {
                err = src->l_info_ops->io_clone(dst, src);
                if (err < 0)
                        goto errout;
        }
 
        return 0;
errout:
        return nl_get_errno();
}
 
static struct nla_policy link_policy[IFLA_MAX+1] = {
        [IFLA_IFNAME]   = { .type = NLA_STRING,
                            .maxlen = IFNAMSIZ },
        [IFLA_MTU]      = { .type = NLA_U32 },
        [IFLA_TXQLEN]   = { .type = NLA_U32 },
        [IFLA_LINK]     = { .type = NLA_U32 },
        [IFLA_WEIGHT]   = { .type = NLA_U32 },
        [IFLA_MASTER]   = { .type = NLA_U32 },
        [IFLA_OPERSTATE]= { .type = NLA_U8 },
        [IFLA_LINKMODE] = { .type = NLA_U8 },
        [IFLA_LINKINFO] = { .type = NLA_NESTED },
        [IFLA_QDISC]    = { .type = NLA_STRING,
                            .maxlen = IFQDISCSIZ },
        [IFLA_STATS]    = { .minlen = sizeof(struct rtnl_link_stats) },
        [IFLA_MAP]      = { .minlen = sizeof(struct rtnl_link_ifmap) },
};
 
static struct nla_policy link_info_policy[IFLA_INFO_MAX+1] = {
        [IFLA_INFO_KIND]        = { .type = NLA_STRING },
        [IFLA_INFO_DATA]        = { .type = NLA_NESTED },
        [IFLA_INFO_XSTATS]      = { .type = NLA_NESTED },
};
 
static int link_msg_parser(struct nl_cache_ops *ops, struct sockaddr_nl *who,
                           struct nlmsghdr *n, struct nl_parser_param *pp)
{
        struct rtnl_link *link;
        struct ifinfomsg *ifi;
        struct nlattr *tb[IFLA_MAX+1];
        int err;
 
        link = rtnl_link_alloc();
        if (link == NULL) {
                err = nl_errno(ENOMEM);
                goto errout;
        }
                
        link->ce_msgtype = n->nlmsg_type;
 
        err = nlmsg_parse(n, sizeof(*ifi), tb, IFLA_MAX, link_policy);
        if (err < 0)
                goto errout;
 
        if (tb[IFLA_IFNAME] == NULL) {
                err = nl_error(EINVAL, "Missing link name TLV");
                goto errout;
        }
 
        nla_strlcpy(link->l_name, tb[IFLA_IFNAME], IFNAMSIZ);
 
        ifi = nlmsg_data(n);
        link->l_family = ifi->ifi_family;
        link->l_arptype = ifi->ifi_type;
        link->l_index = ifi->ifi_index;
        link->l_flags = ifi->ifi_flags;
        link->l_change = ifi->ifi_change;
        link->ce_mask = (LINK_ATTR_IFNAME | LINK_ATTR_FAMILY |
                          LINK_ATTR_ARPTYPE| LINK_ATTR_IFINDEX |
                          LINK_ATTR_FLAGS | LINK_ATTR_CHANGE);
 
        if (tb[IFLA_STATS]) {
                struct rtnl_link_stats *st = nla_data(tb[IFLA_STATS]);
                
                link->l_stats[RTNL_LINK_RX_PACKETS]     = st->rx_packets;
                link->l_stats[RTNL_LINK_RX_BYTES]       = st->rx_bytes;
                link->l_stats[RTNL_LINK_RX_ERRORS]      = st->rx_errors;
                link->l_stats[RTNL_LINK_RX_DROPPED]     = st->rx_dropped;
                link->l_stats[RTNL_LINK_RX_COMPRESSED]  = st->rx_compressed;
                link->l_stats[RTNL_LINK_RX_FIFO_ERR]    = st->rx_fifo_errors;
                link->l_stats[RTNL_LINK_TX_PACKETS]     = st->tx_packets;
                link->l_stats[RTNL_LINK_TX_BYTES]       = st->tx_bytes;
                link->l_stats[RTNL_LINK_TX_ERRORS]      = st->tx_errors;
                link->l_stats[RTNL_LINK_TX_DROPPED]     = st->tx_dropped;
                link->l_stats[RTNL_LINK_TX_COMPRESSED]  = st->tx_compressed;
                link->l_stats[RTNL_LINK_TX_FIFO_ERR]    = st->tx_fifo_errors;
                link->l_stats[RTNL_LINK_RX_LEN_ERR]     = st->rx_length_errors;
                link->l_stats[RTNL_LINK_RX_OVER_ERR]    = st->rx_over_errors;
                link->l_stats[RTNL_LINK_RX_CRC_ERR]     = st->rx_crc_errors;
                link->l_stats[RTNL_LINK_RX_FRAME_ERR]   = st->rx_frame_errors;
                link->l_stats[RTNL_LINK_RX_MISSED_ERR]  = st->rx_missed_errors;
                link->l_stats[RTNL_LINK_TX_ABORT_ERR]   = st->tx_aborted_errors;
                link->l_stats[RTNL_LINK_TX_CARRIER_ERR] = st->tx_carrier_errors;
                link->l_stats[RTNL_LINK_TX_HBEAT_ERR]   = st->tx_heartbeat_errors;
                link->l_stats[RTNL_LINK_TX_WIN_ERR]     = st->tx_window_errors;
                link->l_stats[RTNL_LINK_MULTICAST]      = st->multicast;
 
                link->ce_mask |= LINK_ATTR_STATS;
        }
 
        if (tb[IFLA_TXQLEN]) {
                link->l_txqlen = nla_get_u32(tb[IFLA_TXQLEN]);
                link->ce_mask |= LINK_ATTR_TXQLEN;
        }
 
        if (tb[IFLA_MTU]) {
                link->l_mtu = nla_get_u32(tb[IFLA_MTU]);
                link->ce_mask |= LINK_ATTR_MTU;
        }
 
        if (tb[IFLA_ADDRESS]) {
                link->l_addr = nla_get_addr(tb[IFLA_ADDRESS], AF_UNSPEC);
                if (link->l_addr == NULL)
                        goto errout;
                nl_addr_set_family(link->l_addr,
                                   nl_addr_guess_family(link->l_addr));
                link->ce_mask |= LINK_ATTR_ADDR;
        }
 
        if (tb[IFLA_BROADCAST]) {
                link->l_bcast = nla_get_addr(tb[IFLA_BROADCAST], AF_UNSPEC);
                if (link->l_bcast == NULL)
                        goto errout;
                nl_addr_set_family(link->l_bcast,
                                   nl_addr_guess_family(link->l_bcast));
                link->ce_mask |= LINK_ATTR_BRD;
        }
 
        if (tb[IFLA_LINK]) {
                link->l_link = nla_get_u32(tb[IFLA_LINK]);
                link->ce_mask |= LINK_ATTR_LINK;
        }
 
        if (tb[IFLA_WEIGHT]) {
                link->l_weight = nla_get_u32(tb[IFLA_WEIGHT]);
                link->ce_mask |= LINK_ATTR_WEIGHT;
        }
 
        if (tb[IFLA_QDISC]) {
                nla_strlcpy(link->l_qdisc, tb[IFLA_QDISC], IFQDISCSIZ);
                link->ce_mask |= LINK_ATTR_QDISC;
        }
 
        if (tb[IFLA_MAP]) {
                nla_memcpy(&link->l_map, tb[IFLA_MAP], 
                           sizeof(struct rtnl_link_ifmap));
                link->ce_mask |= LINK_ATTR_MAP;
        }
 
        if (tb[IFLA_MASTER]) {
                link->l_master = nla_get_u32(tb[IFLA_MASTER]);
                link->ce_mask |= LINK_ATTR_MASTER;
        }
 
        if (tb[IFLA_OPERSTATE]) {
                link->l_operstate = nla_get_u8(tb[IFLA_OPERSTATE]);
                link->ce_mask |= LINK_ATTR_OPERSTATE;
        }
 
        if (tb[IFLA_LINKMODE]) {
                link->l_linkmode = nla_get_u8(tb[IFLA_LINKMODE]);
                link->ce_mask |= LINK_ATTR_LINKMODE;
        }
 
        if (tb[IFLA_LINKINFO]) {
                struct nlattr *li[IFLA_INFO_MAX+1];
 
                err = nla_parse_nested(li, IFLA_INFO_MAX, tb[IFLA_LINKINFO],
                                       link_info_policy);
                if (err < 0)
                        goto errout;
 
                if (li[IFLA_INFO_KIND] &&
                    (li[IFLA_INFO_DATA] || li[IFLA_INFO_XSTATS])) {
                        struct rtnl_link_info_ops *ops;
                        char *kind;
 
                        kind = nla_get_string(li[IFLA_INFO_KIND]);
                        ops = rtnl_link_info_ops_lookup(kind);
                        if (ops != NULL) {
                                ops->io_refcnt++;
                                link->l_info_ops = ops;
                                err = ops->io_parse(link, li[IFLA_INFO_DATA],
                                                    li[IFLA_INFO_XSTATS]);
                                if (err < 0)
                                        goto errout;
                        } else {
                                /* XXX: Warn about unparsed info? */
                        }
                }
        }
 
        err = pp->pp_cb((struct nl_object *) link, pp);
        if (err < 0)
                goto errout;
 
        err = P_ACCEPT;
 
errout:
        rtnl_link_put(link);
        return err;
}
 
static int link_request_update(struct nl_cache *c, struct nl_handle *h)
{
        return nl_rtgen_request(h, RTM_GETLINK, AF_UNSPEC, NLM_F_DUMP);
}
 
static int link_dump_brief(struct nl_object *obj, struct nl_dump_params *p)
{
        char buf[128];
        struct nl_cache *cache = dp_cache(obj);
        struct rtnl_link *link = (struct rtnl_link *) obj;
        int line = 1;
 
        dp_dump(p, "%s %s ", link->l_name,
                             nl_llproto2str(link->l_arptype, buf, sizeof(buf)));
 
        if (link->l_addr && !nl_addr_iszero(link->l_addr))
                dp_dump(p, "%s ", nl_addr2str(link->l_addr, buf, sizeof(buf)));
 
        if (link->ce_mask & LINK_ATTR_MASTER) {
                struct rtnl_link *master = rtnl_link_get(cache, link->l_master);
                dp_dump(p, "master %s ", master ? master->l_name : "inv");
                if (master)
                        rtnl_link_put(master);
        }
 
        rtnl_link_flags2str(link->l_flags, buf, sizeof(buf));
        if (buf[0])
                dp_dump(p, "<%s> ", buf);
 
        if (link->ce_mask & LINK_ATTR_LINK) {
                struct rtnl_link *ll = rtnl_link_get(cache, link->l_link);
                dp_dump(p, "slave-of %s ", ll ? ll->l_name : "NONE");
                if (ll)
                        rtnl_link_put(ll);
        }
 
        if (link->l_info_ops && link->l_info_ops->io_dump[NL_DUMP_BRIEF])
                line = link->l_info_ops->io_dump[NL_DUMP_BRIEF](link, p, line);
 
        dp_dump(p, "\n");
 
        return line;
}
 
static int link_dump_full(struct nl_object *obj, struct nl_dump_params *p)
{
        struct rtnl_link *link = (struct rtnl_link *) obj;
        char buf[64];
        int line;
 
        line = link_dump_brief(obj, p);
        dp_new_line(p, line++);
 
        dp_dump(p, "    mtu %u ", link->l_mtu);
        dp_dump(p, "txqlen %u weight %u ", link->l_txqlen, link->l_weight);
 
        if (link->ce_mask & LINK_ATTR_QDISC)
                dp_dump(p, "qdisc %s ", link->l_qdisc);
 
        if (link->ce_mask & LINK_ATTR_MAP && link->l_map.lm_irq)
                dp_dump(p, "irq %u ", link->l_map.lm_irq);
 
        if (link->ce_mask & LINK_ATTR_IFINDEX)
                dp_dump(p, "index %u ", link->l_index);
 
 
        dp_dump(p, "\n");
        dp_new_line(p, line++);
 
        dp_dump(p, "    ");
 
        if (link->ce_mask & LINK_ATTR_BRD)
                dp_dump(p, "brd %s ", nl_addr2str(link->l_bcast, buf,
                                                   sizeof(buf)));
 
        if ((link->ce_mask & LINK_ATTR_OPERSTATE) &&
            link->l_operstate != IF_OPER_UNKNOWN) {
                rtnl_link_operstate2str(link->l_operstate, buf, sizeof(buf));
                dp_dump(p, "state %s ", buf);
        }
 
        dp_dump(p, "mode %s\n",
                rtnl_link_mode2str(link->l_linkmode, buf, sizeof(buf)));
 
        if (link->l_info_ops && link->l_info_ops->io_dump[NL_DUMP_FULL])
                line = link->l_info_ops->io_dump[NL_DUMP_FULL](link, p, line);
 
        return line;
}
 
static int link_dump_stats(struct nl_object *obj, struct nl_dump_params *p)
{
        struct rtnl_link *link = (struct rtnl_link *) obj;
        char *unit, fmt[64];
        float res;
        int line;
        
        line = link_dump_full(obj, p);
 
        dp_dump_line(p, line++, "    Stats:    bytes    packets     errors "
                                "   dropped   fifo-err compressed\n");
 
        res = nl_cancel_down_bytes(link->l_stats[RTNL_LINK_RX_BYTES], &unit);
 
        strcpy(fmt, "    RX  %X.2f %s %10llu %10llu %10llu %10llu %10llu\n");
        fmt[9] = *unit == 'B' ? '9' : '7';
        
        dp_dump_line(p, line++, fmt,
                res, unit,
                link->l_stats[RTNL_LINK_RX_PACKETS],
                link->l_stats[RTNL_LINK_RX_ERRORS],
                link->l_stats[RTNL_LINK_RX_DROPPED],
                link->l_stats[RTNL_LINK_RX_FIFO_ERR],
                link->l_stats[RTNL_LINK_RX_COMPRESSED]);
 
        res = nl_cancel_down_bytes(link->l_stats[RTNL_LINK_TX_BYTES], &unit);
 
        strcpy(fmt, "    TX  %X.2f %s %10llu %10llu %10llu %10llu %10llu\n");
        fmt[9] = *unit == 'B' ? '9' : '7';
        
        dp_dump_line(p, line++, fmt,
                res, unit,
                link->l_stats[RTNL_LINK_TX_PACKETS],
                link->l_stats[RTNL_LINK_TX_ERRORS],
                link->l_stats[RTNL_LINK_TX_DROPPED],
                link->l_stats[RTNL_LINK_TX_FIFO_ERR],
                link->l_stats[RTNL_LINK_TX_COMPRESSED]);
 
        dp_dump_line(p, line++, "    Errors:  length       over        crc "
                                "     frame     missed  multicast\n");
 
        dp_dump_line(p, line++, "    RX   %10" PRIu64 " %10" PRIu64 " %10"
                                PRIu64 " %10" PRIu64 " %10" PRIu64 " %10"
                                PRIu64 "\n",
                link->l_stats[RTNL_LINK_RX_LEN_ERR],
                link->l_stats[RTNL_LINK_RX_OVER_ERR],
                link->l_stats[RTNL_LINK_RX_CRC_ERR],
                link->l_stats[RTNL_LINK_RX_FRAME_ERR],
                link->l_stats[RTNL_LINK_RX_MISSED_ERR],
                link->l_stats[RTNL_LINK_MULTICAST]);
 
        dp_dump_line(p, line++, "    Errors: aborted    carrier  heartbeat "
                                "    window  collision\n");
        
        dp_dump_line(p, line++, "    TX   %10" PRIu64 " %10" PRIu64 " %10"
                                PRIu64 " %10" PRIu64 " %10" PRIu64 "\n",
                link->l_stats[RTNL_LINK_TX_ABORT_ERR],
                link->l_stats[RTNL_LINK_TX_CARRIER_ERR],
                link->l_stats[RTNL_LINK_TX_HBEAT_ERR],
                link->l_stats[RTNL_LINK_TX_WIN_ERR],
                link->l_stats[RTNL_LINK_TX_COLLISIONS]);
 
        if (link->l_info_ops && link->l_info_ops->io_dump[NL_DUMP_STATS])
                line = link->l_info_ops->io_dump[NL_DUMP_STATS](link, p, line);
 
        return line;
}
 
static int link_dump_xml(struct nl_object *obj, struct nl_dump_params *p)
{
        struct rtnl_link *link = (struct rtnl_link *) obj;
        struct nl_cache *cache = dp_cache(obj);
        char buf[128];
        int i, line = 0;
 
        dp_dump_line(p, line++, "<link name=\"%s\" index=\"%u\">\n",
                     link->l_name, link->l_index);
        dp_dump_line(p, line++, "  <family>%s</family>\n",
                     nl_af2str(link->l_family, buf, sizeof(buf)));
        dp_dump_line(p, line++, "  <arptype>%s</arptype>\n",
                     nl_llproto2str(link->l_arptype, buf, sizeof(buf)));
        dp_dump_line(p, line++, "  <address>%s</address>\n",
                     nl_addr2str(link->l_addr, buf, sizeof(buf)));
        dp_dump_line(p, line++, "  <mtu>%u</mtu>\n", link->l_mtu);
        dp_dump_line(p, line++, "  <txqlen>%u</txqlen>\n", link->l_txqlen);
        dp_dump_line(p, line++, "  <weight>%u</weight>\n", link->l_weight);
 
        rtnl_link_flags2str(link->l_flags, buf, sizeof(buf));
        if (buf[0])
                dp_dump_line(p, line++, "  <flags>%s</flags>\n", buf);
 
        if (link->ce_mask & LINK_ATTR_QDISC)
                dp_dump_line(p, line++, "  <qdisc>%s</qdisc>\n", link->l_qdisc);
 
        if (link->ce_mask & LINK_ATTR_LINK) {
                struct rtnl_link *ll = rtnl_link_get(cache, link->l_link);
                dp_dump_line(p, line++, "  <link>%s</link>\n",
                             ll ? ll->l_name : "none");
                if (ll)
                        rtnl_link_put(ll);
        }
 
        if (link->ce_mask & LINK_ATTR_MASTER) {
                struct rtnl_link *master = rtnl_link_get(cache, link->l_master);
                dp_dump_line(p, line++, "  <master>%s</master>\n",
                             master ? master->l_name : "none");
                if (master)
                        rtnl_link_put(master);
        }
 
        if (link->ce_mask & LINK_ATTR_BRD)
                dp_dump_line(p, line++, "  <broadcast>%s</broadcast>\n",
                             nl_addr2str(link->l_bcast, buf, sizeof(buf)));
 
        if (link->ce_mask & LINK_ATTR_STATS) {
                dp_dump_line(p, line++, "  <stats>\n");
                for (i = 0; i <= RTNL_LINK_STATS_MAX; i++) {
                        rtnl_link_stat2str(i, buf, sizeof(buf));
                        dp_dump_line(p, line++,
                                     "    <%s>%" PRIu64 "</%s>\n",
                                     buf, link->l_stats[i], buf);
                }
                dp_dump_line(p, line++, "  </stats>\n");
        }
 
        if (link->l_info_ops && link->l_info_ops->io_dump[NL_DUMP_XML]) {
                dp_dump_line(p, line++, "  <info>\n");
                line = link->l_info_ops->io_dump[NL_DUMP_XML](link, p, line);
                dp_dump_line(p, line++, "  </info>\n");
        }
 
        dp_dump_line(p, line++, "</link>\n");
 
#if 0
        uint32_t        l_change;       /**< Change mask */
        struct rtnl_lifmap l_map;       /**< Interface device mapping */
#endif
 
        return line;
}
 
static int link_dump_env(struct nl_object *obj, struct nl_dump_params *p)
{
        struct rtnl_link *link = (struct rtnl_link *) obj;
        struct nl_cache *cache = dp_cache(obj);
        char buf[128];
        int i, line = 0;
 
        dp_dump_line(p, line++, "LINK_NAME=%s\n", link->l_name);
        dp_dump_line(p, line++, "LINK_IFINDEX=%u\n", link->l_index);
        dp_dump_line(p, line++, "LINK_FAMILY=%s\n",
                     nl_af2str(link->l_family, buf, sizeof(buf)));
        dp_dump_line(p, line++, "LINK_TYPE=%s\n",
                     nl_llproto2str(link->l_arptype, buf, sizeof(buf)));
        if (link->ce_mask & LINK_ATTR_ADDR)
                dp_dump_line(p, line++, "LINK_ADDRESS=%s\n",
                             nl_addr2str(link->l_addr, buf, sizeof(buf)));
        dp_dump_line(p, line++, "LINK_MTU=%u\n", link->l_mtu);
        dp_dump_line(p, line++, "LINK_TXQUEUELEN=%u\n", link->l_txqlen);
        dp_dump_line(p, line++, "LINK_WEIGHT=%u\n", link->l_weight);
 
        rtnl_link_flags2str(link->l_flags & ~IFF_RUNNING, buf, sizeof(buf));
        if (buf[0])
                dp_dump_line(p, line++, "LINK_FLAGS=%s\n", buf);
 
        if (link->ce_mask & LINK_ATTR_QDISC)
                dp_dump_line(p, line++, "LINK_QDISC=%s\n", link->l_qdisc);
 
        if (link->ce_mask & LINK_ATTR_LINK) {
                struct rtnl_link *ll = rtnl_link_get(cache, link->l_link);
 
                dp_dump_line(p, line++, "LINK_LINK_IFINDEX=%d\n", link->l_link);
                if (ll) {
                        dp_dump_line(p, line++, "LINK_LINK_IFNAME=%s\n",
                                     ll->l_name);
                        rtnl_link_put(ll);
                }
        }
 
        if (link->ce_mask & LINK_ATTR_MASTER) {
                struct rtnl_link *master = rtnl_link_get(cache, link->l_master);
                dp_dump_line(p, line++, "LINK_MASTER=%s\n",
                             master ? master->l_name : "none");
                if (master)
                        rtnl_link_put(master);
        }
 
        if (link->ce_mask & LINK_ATTR_BRD)
                dp_dump_line(p, line++, "LINK_BROADCAST=%s\n",
                             nl_addr2str(link->l_bcast, buf, sizeof(buf)));
 
        if (link->ce_mask & LINK_ATTR_STATS) {
                for (i = 0; i <= RTNL_LINK_STATS_MAX; i++) {
                        char *c = buf;
 
                        sprintf(buf, "LINK_");
                        rtnl_link_stat2str(i, buf + 5, sizeof(buf) - 5);
                        while (*c) {
                                *c = toupper(*c);
                                c++;
                        }
                        dp_dump_line(p, line++,
                                     "%s=%" PRIu64 "\n", buf, link->l_stats[i]);
                }
        }
 
        if (link->l_info_ops && link->l_info_ops->io_dump[NL_DUMP_ENV])
                line = link->l_info_ops->io_dump[NL_DUMP_ENV](link, p, line);
 
        return line;
}
 
#if 0
static int link_handle_event(struct nl_object *a, struct rtnl_link_event_cb *cb)
{
        struct rtnl_link *l = (struct rtnl_link *) a;
        struct nl_cache *c = dp_cache(a);
        int nevents = 0;
 
        if (l->l_change == ~0U) {
                if (l->ce_msgtype == RTM_NEWLINK)
                        cb->le_register(l);
                else
                        cb->le_unregister(l);
 
                return 1;
        }
 
        if (l->l_change & IFF_SLAVE) {
                if (l->l_flags & IFF_SLAVE) {
                        struct rtnl_link *m = rtnl_link_get(c, l->l_master);
                        cb->le_new_bonding(l, m);
                        if (m)
                                rtnl_link_put(m);
                } else
                        cb->le_cancel_bonding(l);
        }
 
#if 0
        if (l->l_change & IFF_UP && l->l_change & IFF_RUNNING)
                dp_dump_line(p, line++, "link %s changed state to %s.\n",
                        l->l_name, l->l_flags & IFF_UP ? "up" : "down");
 
        if (l->l_change & IFF_PROMISC) {
                dp_new_line(p, line++);
                dp_dump(p, "link %s %s promiscuous mode.\n",
                    l->l_name, l->l_flags & IFF_PROMISC ? "entered" : "left");
        }
 
        if (line == 0)
                dp_dump_line(p, line++, "link %s sent unknown event.\n",
                             l->l_name);
#endif
 
        return nevents;
}
#endif
 
static int link_compare(struct nl_object *_a, struct nl_object *_b,
                        uint32_t attrs, int flags)
{
        struct rtnl_link *a = (struct rtnl_link *) _a;
        struct rtnl_link *b = (struct rtnl_link *) _b;
        int diff = 0;
 
#define LINK_DIFF(ATTR, EXPR) ATTR_DIFF(attrs, LINK_ATTR_##ATTR, a, b, EXPR)
 
        diff |= LINK_DIFF(IFINDEX,      a->l_index != b->l_index);
        diff |= LINK_DIFF(MTU,          a->l_mtu != b->l_mtu);
        diff |= LINK_DIFF(LINK,         a->l_link != b->l_link);
        diff |= LINK_DIFF(TXQLEN,       a->l_txqlen != b->l_txqlen);
        diff |= LINK_DIFF(WEIGHT,       a->l_weight != b->l_weight);
        diff |= LINK_DIFF(MASTER,       a->l_master != b->l_master);
        diff |= LINK_DIFF(FAMILY,       a->l_family != b->l_family);
        diff |= LINK_DIFF(OPERSTATE,    a->l_operstate != b->l_operstate);
        diff |= LINK_DIFF(LINKMODE,     a->l_linkmode != b->l_linkmode);
        diff |= LINK_DIFF(QDISC,        strcmp(a->l_qdisc, b->l_qdisc));
        diff |= LINK_DIFF(IFNAME,       strcmp(a->l_name, b->l_name));
        diff |= LINK_DIFF(ADDR,         nl_addr_cmp(a->l_addr, b->l_addr));
        diff |= LINK_DIFF(BRD,          nl_addr_cmp(a->l_bcast, b->l_bcast));
 
        if (flags & LOOSE_FLAG_COMPARISON)
                diff |= LINK_DIFF(FLAGS,
                                  (a->l_flags ^ b->l_flags) & b->l_flag_mask);
        else
                diff |= LINK_DIFF(FLAGS, a->l_flags != b->l_flags);
 
#undef LINK_DIFF
 
        return diff;
}
 
static struct trans_tbl link_attrs[] = {
        __ADD(LINK_ATTR_MTU, mtu)
        __ADD(LINK_ATTR_LINK, link)
        __ADD(LINK_ATTR_TXQLEN, txqlen)
        __ADD(LINK_ATTR_WEIGHT, weight)
        __ADD(LINK_ATTR_MASTER, master)
        __ADD(LINK_ATTR_QDISC, qdisc)
        __ADD(LINK_ATTR_MAP, map)
        __ADD(LINK_ATTR_ADDR, address)
        __ADD(LINK_ATTR_BRD, broadcast)
        __ADD(LINK_ATTR_FLAGS, flags)
        __ADD(LINK_ATTR_IFNAME, name)
        __ADD(LINK_ATTR_IFINDEX, ifindex)
        __ADD(LINK_ATTR_FAMILY, family)
        __ADD(LINK_ATTR_ARPTYPE, arptype)
        __ADD(LINK_ATTR_STATS, stats)
        __ADD(LINK_ATTR_CHANGE, change)
        __ADD(LINK_ATTR_OPERSTATE, operstate)
        __ADD(LINK_ATTR_LINKMODE, linkmode)
};
 
static char *link_attrs2str(int attrs, char *buf, size_t len)
{
        return __flags2str(attrs, buf, len, link_attrs,
                           ARRAY_SIZE(link_attrs));
}
 
/**
 * @name Allocation/Freeing
 * @{
 */
 
struct rtnl_link *rtnl_link_alloc(void)
{
        return (struct rtnl_link *) nl_object_alloc(&link_obj_ops);
}
 
void rtnl_link_put(struct rtnl_link *link)
{
        nl_object_put((struct nl_object *) link);
}
 
/** @} */
 
/**
 * @name Cache Management
 * @{
 */
 
 
/**
 * Allocate link cache and fill in all configured links.
 * @arg handle          Netlink handle.
 *
 * Allocates a new link cache, initializes it properly and updates it
 * to include all links currently configured in the kernel.
 *
 * @note Free the memory after usage.
 * @return Newly allocated cache or NULL if an error occured.
 */
struct nl_cache *rtnl_link_alloc_cache(struct nl_handle *handle)
{
        struct nl_cache * cache;
        
        cache = nl_cache_alloc(&rtnl_link_ops);
        if (cache == NULL)
                return NULL;
        
        if (handle && nl_cache_refill(handle, cache) < 0) {
                nl_cache_free(cache);
                return NULL;
        }
 
        return cache;
}
 
/**
 * Look up link by interface index in the provided cache
 * @arg cache           link cache
 * @arg ifindex         link interface index
 *
 * The caller owns a reference on the returned object and
 * must give the object back via rtnl_link_put().
 *
 * @return pointer to link inside the cache or NULL if no match was found.
 */
struct rtnl_link *rtnl_link_get(struct nl_cache *cache, int ifindex)
{
        struct rtnl_link *link;
 
        if (cache->c_ops != &rtnl_link_ops)
                return NULL;
 
        nl_list_for_each_entry(link, &cache->c_items, ce_list) {
                if (link->l_index == ifindex) {
                        nl_object_get((struct nl_object *) link);
                        return link;
                }
        }
 
        return NULL;
}
 
/**
 * Look up link by link name in the provided cache
 * @arg cache           link cache
 * @arg name            link name
 *
 * The caller owns a reference on the returned object and
 * must give the object back via rtnl_link_put().
 *
 * @return pointer to link inside the cache or NULL if no match was found.
 */
struct rtnl_link *rtnl_link_get_by_name(struct nl_cache *cache,
                                         const char *name)
{
        struct rtnl_link *link;
 
        if (cache->c_ops != &rtnl_link_ops)
                return NULL;
 
        nl_list_for_each_entry(link, &cache->c_items, ce_list) {
                if (!strcmp(name, link->l_name)) {
                        nl_object_get((struct nl_object *) link);
                        return link;
                }
        }
 
        return NULL;
}
 
/** @} */
 
/**
 * @name Link Modifications
 * @{
 */
 
/**
 * Builds a netlink change request message to change link attributes
 * @arg old             link to be changed
 * @arg tmpl            template with requested changes
 * @arg flags           additional netlink message flags
 *
 * Builds a new netlink message requesting a change of link attributes.
 * The netlink message header isn't fully equipped with all relevant
 * fields and must be sent out via nl_send_auto_complete() or
 * supplemented as needed.
 * \a old must point to a link currently configured in the kernel
 * and \a tmpl must contain the attributes to be changed set via
 * \c rtnl_link_set_* functions.
 *
 * @return New netlink message
 * @note Not all attributes can be changed, see
 *       \ref link_changeable "Changeable Attributes" for more details.
 */
struct nl_msg * rtnl_link_build_change_request(struct rtnl_link *old,
                                               struct rtnl_link *tmpl,
                                               int flags)
{
        struct nl_msg *msg;
        struct ifinfomsg ifi = {
                .ifi_family = old->l_family,
                .ifi_index = old->l_index,
        };
 
        if (tmpl->ce_mask & LINK_ATTR_FLAGS) {
                ifi.ifi_flags = old->l_flags & ~tmpl->l_flag_mask;
                ifi.ifi_flags |= tmpl->l_flags;
        }
 
        msg = nlmsg_alloc_simple(RTM_SETLINK, flags);
        if (!msg)
                goto nla_put_failure;
 
        if (nlmsg_append(msg, &ifi, sizeof(ifi), NLMSG_ALIGNTO) < 0)
                goto nla_put_failure;
 
        if (tmpl->ce_mask & LINK_ATTR_ADDR)
                NLA_PUT_ADDR(msg, IFLA_ADDRESS, tmpl->l_addr);
 
        if (tmpl->ce_mask & LINK_ATTR_BRD)
                NLA_PUT_ADDR(msg, IFLA_BROADCAST, tmpl->l_bcast);
 
        if (tmpl->ce_mask & LINK_ATTR_MTU)
                NLA_PUT_U32(msg, IFLA_MTU, tmpl->l_mtu);
 
        if (tmpl->ce_mask & LINK_ATTR_TXQLEN)
                NLA_PUT_U32(msg, IFLA_TXQLEN, tmpl->l_txqlen);
 
        if (tmpl->ce_mask & LINK_ATTR_WEIGHT)
                NLA_PUT_U32(msg, IFLA_WEIGHT, tmpl->l_weight);
 
        if (tmpl->ce_mask & LINK_ATTR_IFNAME)
                NLA_PUT_STRING(msg, IFLA_IFNAME, tmpl->l_name);
 
        if (tmpl->ce_mask & LINK_ATTR_OPERSTATE)
                NLA_PUT_U8(msg, IFLA_OPERSTATE, tmpl->l_operstate);
 
        if (tmpl->ce_mask & LINK_ATTR_LINKMODE)
                NLA_PUT_U8(msg, IFLA_LINKMODE, tmpl->l_linkmode);
 
        if ((tmpl->ce_mask & LINK_ATTR_LINKINFO) && tmpl->l_info_ops &&
            tmpl->l_info_ops->io_put_attrs) {
                struct nlattr *info;
 
                if (!(info = nla_nest_start(msg, IFLA_LINKINFO)))
                        goto nla_put_failure;
 
                NLA_PUT_STRING(msg, IFLA_INFO_KIND, tmpl->l_info_ops->io_name);
 
                if (tmpl->l_info_ops->io_put_attrs(msg, tmpl) < 0)
                        goto nla_put_failure;
 
                nla_nest_end(msg, info);
        }
 
        return msg;
 
nla_put_failure:
        nlmsg_free(msg);
        return NULL;
}
 
/**
 * Change link attributes
 * @arg handle          netlink handle
 * @arg old             link to be changed
 * @arg tmpl            template with requested changes
 * @arg flags           additional netlink message flags
 *
 * Builds a new netlink message by calling rtnl_link_build_change_request(),
 * sends the request to the kernel and waits for the next ACK to be
 * received, i.e. blocks until the request has been processed.
 *
 * @return 0 on success or a negative error code
 * @note Not all attributes can be changed, see
 *       \ref link_changeable "Changeable Attributes" for more details.
 */
int rtnl_link_change(struct nl_handle *handle, struct rtnl_link *old,
                     struct rtnl_link *tmpl, int flags)
{
        int err;
        struct nl_msg *msg;
        
        msg = rtnl_link_build_change_request(old, tmpl, flags);
        if (!msg)
                return nl_errno(ENOMEM);
        
        err = nl_send_auto_complete(handle, msg);
        nlmsg_free(msg);
        if (err < 0)
                return err;
 
        return nl_wait_for_ack(handle);
}
 
/** @} */
 
/**
 * @name Name <-> Index Translations
 * @{
 */
 
/**
 * Translate an interface index to the corresponding link name
 * @arg cache           link cache
 * @arg ifindex         link interface index
 * @arg dst             destination buffer
 * @arg len             length of destination buffer
 *
 * Translates the specified interface index to the corresponding
 * link name and stores the name in the destination buffer.
 *
 * @return link name or NULL if no match was found.
 */
char * rtnl_link_i2name(struct nl_cache *cache, int ifindex, char *dst,
                        size_t len)
{
        struct rtnl_link *link = rtnl_link_get(cache, ifindex);
 
        if (link) {
                strncpy(dst, link->l_name, len - 1);
                rtnl_link_put(link);
                return dst;
        }
 
        return NULL;
}
 
/**
 * Translate a link name to the corresponding interface index
 * @arg cache           link cache
 * @arg name            link name
 *
 * @return interface index or RTNL_LINK_NOT_FOUND if no match was found.
 */
int rtnl_link_name2i(struct nl_cache *cache, const char *name)
{
        int ifindex = RTNL_LINK_NOT_FOUND;
        struct rtnl_link *link;
        
        link = rtnl_link_get_by_name(cache, name);
        if (link) {
                ifindex = link->l_index;
                rtnl_link_put(link);
        }
 
        return ifindex;
}
 
/** @} */
 
/**
 * @name Link Flags Translations
 * @{
 */
 
static struct trans_tbl link_flags[] = {
        __ADD(IFF_LOOPBACK, loopback)
        __ADD(IFF_BROADCAST, broadcast)
        __ADD(IFF_POINTOPOINT, pointopoint)
        __ADD(IFF_MULTICAST, multicast)
        __ADD(IFF_NOARP, noarp)
        __ADD(IFF_ALLMULTI, allmulti)
        __ADD(IFF_PROMISC, promisc)
        __ADD(IFF_MASTER, master)
        __ADD(IFF_SLAVE, slave)
        __ADD(IFF_DEBUG, debug)
        __ADD(IFF_DYNAMIC, dynamic)
        __ADD(IFF_AUTOMEDIA, automedia)
        __ADD(IFF_PORTSEL, portsel)
        __ADD(IFF_NOTRAILERS, notrailers)
        __ADD(IFF_UP, up)
        __ADD(IFF_RUNNING, running)
        __ADD(IFF_LOWER_UP, lowerup)
        __ADD(IFF_DORMANT, dormant)
        __ADD(IFF_ECHO, echo)
};
 
char * rtnl_link_flags2str(int flags, char *buf, size_t len)
{
        return __flags2str(flags, buf, len, link_flags,
                           ARRAY_SIZE(link_flags));
}
 
int rtnl_link_str2flags(const char *name)
{
        return __str2flags(name, link_flags, ARRAY_SIZE(link_flags));
}
 
/** @} */
 
/**
 * @name Link Statistics Translations
 * @{
 */
 
static struct trans_tbl link_stats[] = {
        __ADD(RTNL_LINK_RX_PACKETS, rx_packets)
        __ADD(RTNL_LINK_TX_PACKETS, tx_packets)
        __ADD(RTNL_LINK_RX_BYTES, rx_bytes)
        __ADD(RTNL_LINK_TX_BYTES, tx_bytes)
        __ADD(RTNL_LINK_RX_ERRORS, rx_errors)
        __ADD(RTNL_LINK_TX_ERRORS, tx_errors)
        __ADD(RTNL_LINK_RX_DROPPED, rx_dropped)
        __ADD(RTNL_LINK_TX_DROPPED, tx_dropped)
        __ADD(RTNL_LINK_RX_COMPRESSED, rx_compressed)
        __ADD(RTNL_LINK_TX_COMPRESSED, tx_compressed)
        __ADD(RTNL_LINK_RX_FIFO_ERR, rx_fifo_err)
        __ADD(RTNL_LINK_TX_FIFO_ERR, tx_fifo_err)
        __ADD(RTNL_LINK_RX_LEN_ERR, rx_len_err)
        __ADD(RTNL_LINK_RX_OVER_ERR, rx_over_err)
        __ADD(RTNL_LINK_RX_CRC_ERR, rx_crc_err)
        __ADD(RTNL_LINK_RX_FRAME_ERR, rx_frame_err)
        __ADD(RTNL_LINK_RX_MISSED_ERR, rx_missed_err)
        __ADD(RTNL_LINK_TX_ABORT_ERR, tx_abort_err)
        __ADD(RTNL_LINK_TX_CARRIER_ERR, tx_carrier_err)
        __ADD(RTNL_LINK_TX_HBEAT_ERR, tx_hbeat_err)
        __ADD(RTNL_LINK_TX_WIN_ERR, tx_win_err)
        __ADD(RTNL_LINK_TX_COLLISIONS, tx_collision)
        __ADD(RTNL_LINK_MULTICAST, multicast)
};
 
char *rtnl_link_stat2str(int st, char *buf, size_t len)
{
        return __type2str(st, buf, len, link_stats, ARRAY_SIZE(link_stats));
}
 
int rtnl_link_str2stat(const char *name)
{
        return __str2type(name, link_stats, ARRAY_SIZE(link_stats));
}
 
/** @} */
 
/**
 * @name Link Operstate Translations
 * @{
 */
 
static struct trans_tbl link_operstates[] = {
        __ADD(IF_OPER_UNKNOWN, unknown)
        __ADD(IF_OPER_NOTPRESENT, notpresent)
        __ADD(IF_OPER_DOWN, down)
        __ADD(IF_OPER_LOWERLAYERDOWN, lowerlayerdown)
        __ADD(IF_OPER_TESTING, testing)
        __ADD(IF_OPER_DORMANT, dormant)
        __ADD(IF_OPER_UP, up)
};
 
char *rtnl_link_operstate2str(int st, char *buf, size_t len)
{
        return __type2str(st, buf, len, link_operstates,
                          ARRAY_SIZE(link_operstates));
}
 
int rtnl_link_str2operstate(const char *name)
{
        return __str2type(name, link_operstates,
                          ARRAY_SIZE(link_operstates));
}
 
/** @} */
 
/**
 * @name Link Mode Translations
 * @{
 */
 
static struct trans_tbl link_modes[] = {
        __ADD(IF_LINK_MODE_DEFAULT, default)
        __ADD(IF_LINK_MODE_DORMANT, dormant)
};
 
char *rtnl_link_mode2str(int st, char *buf, size_t len)
{
        return __type2str(st, buf, len, link_modes, ARRAY_SIZE(link_modes));
}
 
int rtnl_link_str2mode(const char *name)
{
        return __str2type(name, link_modes, ARRAY_SIZE(link_modes));
}
 
/** @} */
 
/**
 * @name Attributes
 * @{
 */
 
void rtnl_link_set_qdisc(struct rtnl_link *link, const char *qdisc)
{
        strncpy(link->l_qdisc, qdisc, sizeof(link->l_qdisc) - 1);
        link->ce_mask |= LINK_ATTR_QDISC;
}
 
char *rtnl_link_get_qdisc(struct rtnl_link *link)
{
        if (link->ce_mask & LINK_ATTR_QDISC)
                return link->l_qdisc;
        else
                return NULL;
}
 
void rtnl_link_set_name(struct rtnl_link *link, const char *name)
{
        strncpy(link->l_name, name, sizeof(link->l_name) - 1);
        link->ce_mask |= LINK_ATTR_IFNAME;
}
 
char *rtnl_link_get_name(struct rtnl_link *link)
{
        if (link->ce_mask & LINK_ATTR_IFNAME)
                return link->l_name;
        else
                return NULL;
}
 
static inline void __assign_addr(struct rtnl_link *link, struct nl_addr **pos,
                                 struct nl_addr *new, int flag)
{
        if (*pos)
                nl_addr_put(*pos);
 
        nl_addr_get(new);
        *pos = new;
 
        link->ce_mask |= flag;
}
 
void rtnl_link_set_addr(struct rtnl_link *link, struct nl_addr *addr)
{
        __assign_addr(link, &link->l_addr, addr, LINK_ATTR_ADDR);
}
 
struct nl_addr *rtnl_link_get_addr(struct rtnl_link *link)
{
        if (link->ce_mask & LINK_ATTR_ADDR)
                return link->l_addr;
        else
                return NULL;
}
 
void rtnl_link_set_broadcast(struct rtnl_link *link, struct nl_addr *brd)
{
        __assign_addr(link, &link->l_bcast, brd, LINK_ATTR_BRD);
}
 
struct nl_addr *rtnl_link_get_broadcast(struct rtnl_link *link)
{
        if (link->ce_mask & LINK_ATTR_BRD)
                return link->l_bcast;
        else
                return NULL;
}
 
void rtnl_link_set_flags(struct rtnl_link *link, unsigned int flags)
{
        link->l_flag_mask |= flags;
        link->l_flags |= flags;
        link->ce_mask |= LINK_ATTR_FLAGS;
}
 
void rtnl_link_unset_flags(struct rtnl_link *link, unsigned int flags)
{
        link->l_flag_mask |= flags;
        link->l_flags &= ~flags;
        link->ce_mask |= LINK_ATTR_FLAGS;
}
 
unsigned int rtnl_link_get_flags(struct rtnl_link *link)
{
        return link->l_flags;
}
 
void rtnl_link_set_family(struct rtnl_link *link, int family)
{
        link->l_family = family;
        link->ce_mask |= LINK_ATTR_FAMILY;
}
 
int rtnl_link_get_family(struct rtnl_link *link)
{
        if (link->l_family & LINK_ATTR_FAMILY)
                return link->l_family;
        else
                return AF_UNSPEC;
}
 
void rtnl_link_set_arptype(struct rtnl_link *link, unsigned int arptype)
{
        link->l_arptype = arptype;
}
 
unsigned int rtnl_link_get_arptype(struct rtnl_link *link)
{
        return link->l_arptype;
}
 
void rtnl_link_set_ifindex(struct rtnl_link *link, int ifindex)
{
        link->l_index = ifindex;
        link->ce_mask |= LINK_ATTR_IFINDEX;
}
 
int rtnl_link_get_ifindex(struct rtnl_link *link)
{
        if (link->ce_mask & LINK_ATTR_IFINDEX)
                return link->l_index;
        else
                return RTNL_LINK_NOT_FOUND;
}
 
void rtnl_link_set_mtu(struct rtnl_link *link, unsigned int mtu)
{
        link->l_mtu = mtu;
        link->ce_mask |= LINK_ATTR_MTU;
}
 
unsigned int rtnl_link_get_mtu(struct rtnl_link *link)
{
        if (link->ce_mask & LINK_ATTR_MTU)
                return link->l_mtu;
        else
                return 0;
}
 
void rtnl_link_set_txqlen(struct rtnl_link *link, unsigned int txqlen)
{
        link->l_txqlen = txqlen;
        link->ce_mask |= LINK_ATTR_TXQLEN;
}
 
unsigned int rtnl_link_get_txqlen(struct rtnl_link *link)
{
        if (link->ce_mask & LINK_ATTR_TXQLEN)
                return link->l_txqlen;
        else
                return UINT_MAX;
}
 
void rtnl_link_set_weight(struct rtnl_link *link, unsigned int weight)
{
        link->l_weight = weight;
        link->ce_mask |= LINK_ATTR_WEIGHT;
}
 
unsigned int rtnl_link_get_weight(struct rtnl_link *link)
{
        if (link->ce_mask & LINK_ATTR_WEIGHT)
                return link->l_weight;
        else
                return UINT_MAX;
}
 
void rtnl_link_set_link(struct rtnl_link *link, int ifindex)
{
        link->l_link = ifindex;
        link->ce_mask |= LINK_ATTR_LINK;
}
 
int rtnl_link_get_link(struct rtnl_link *link)
{
        if (link->ce_mask & LINK_ATTR_LINK)
                return link->l_link;
        else
                return RTNL_LINK_NOT_FOUND;
}
 
void rtnl_link_set_master(struct rtnl_link *link, int ifindex)
{
        link->l_master = ifindex;
        link->ce_mask |= LINK_ATTR_MASTER;
}
 
int rtnl_link_get_master(struct rtnl_link *link)
{
        if (link->ce_mask & LINK_ATTR_MASTER)
                return link->l_master;
        else
                return RTNL_LINK_NOT_FOUND;
}
 
void rtnl_link_set_operstate(struct rtnl_link *link, uint8_t operstate)
{
        link->l_operstate = operstate;
        link->ce_mask |= LINK_ATTR_OPERSTATE;
}
 
uint8_t rtnl_link_get_operstate(struct rtnl_link *link)
{
        if (link->ce_mask & LINK_ATTR_OPERSTATE)
                return link->l_operstate;
        else
                return IF_OPER_UNKNOWN;
}
 
void rtnl_link_set_linkmode(struct rtnl_link *link, uint8_t linkmode)
{
        link->l_linkmode = linkmode;
        link->ce_mask |= LINK_ATTR_LINKMODE;
}
 
uint8_t rtnl_link_get_linkmode(struct rtnl_link *link)
{
        if (link->ce_mask & LINK_ATTR_LINKMODE)
                return link->l_linkmode;
        else
                return IF_LINK_MODE_DEFAULT;
}
 
uint64_t rtnl_link_get_stat(struct rtnl_link *link, int id)
{
        if (id < 0 || id > RTNL_LINK_STATS_MAX)
                return 0;
 
        return link->l_stats[id];
}
 
/**
 * Specify the info type of a link
 * @arg link    link object
 * @arg type    info type
 *
 * Looks up the info type and prepares the link to store info type
 * specific attributes. If an info type has been assigned already
 * it will be released with all changes lost.
 *
 * @return 0 on success or a negative errror code.
 */
int rtnl_link_set_info_type(struct rtnl_link *link, const char *type)
{
        struct rtnl_link_info_ops *io;
        int err;
 
        if ((io = rtnl_link_info_ops_lookup(type)) == NULL)
                return nl_error(ENOENT, "No such link info type exists");
 
        if (link->l_info_ops)
                release_link_info(link);
 
        if ((err = io->io_alloc(link)) < 0)
                return err;
 
        link->l_info_ops = io;
 
        return 0;
}
 
/**
 * Return info type of a link
 * @arg link    link object
 *
 * @note The returned pointer is only valid as long as the link exists
 * @return Info type name or NULL if unknown.
 */
char *rtnl_link_get_info_type(struct rtnl_link *link)
{
        if (link->l_info_ops)
                return link->l_info_ops->io_name;
        else
                return NULL;
}
 
/** @} */
 
static struct nl_object_ops link_obj_ops = {
        .oo_name                = "route/link",
        .oo_size                = sizeof(struct rtnl_link),
        .oo_free_data           = link_free_data,
        .oo_clone               = link_clone,
        .oo_dump[NL_DUMP_BRIEF] = link_dump_brief,
        .oo_dump[NL_DUMP_FULL]  = link_dump_full,
        .oo_dump[NL_DUMP_STATS] = link_dump_stats,
        .oo_dump[NL_DUMP_XML]   = link_dump_xml,
        .oo_dump[NL_DUMP_ENV]   = link_dump_env,
        .oo_compare             = link_compare,
        .oo_attrs2str           = link_attrs2str,
        .oo_id_attrs            = LINK_ATTR_IFINDEX,
};
 
static struct nl_af_group link_groups[] = {
        { AF_UNSPEC,    RTNLGRP_LINK },
        { END_OF_GROUP_LIST },
};
 
static struct nl_cache_ops rtnl_link_ops = {
        .co_name                = "route/link",
        .co_hdrsize             = sizeof(struct ifinfomsg),
        .co_msgtypes            = {
                                        { RTM_NEWLINK, NL_ACT_NEW, "new" },
                                        { RTM_DELLINK, NL_ACT_DEL, "del" },
                                        { RTM_GETLINK, NL_ACT_GET, "get" },
                                        END_OF_MSGTYPES_LIST,
                                  },
        .co_protocol            = NETLINK_ROUTE,
        .co_groups              = link_groups,
        .co_request_update      = link_request_update,
        .co_msg_parser          = link_msg_parser,
        .co_obj_ops             = &link_obj_ops,
};
 
static void __init link_init(void)
{
        nl_cache_mngt_register(&rtnl_link_ops);
}
 
static void __exit link_exit(void)
{
        nl_cache_mngt_unregister(&rtnl_link_ops);
}
 
/** @} */