Пример #1
0
int tca_build_msg(struct rtnl_tc *tca, int type, int flags,
		  struct nl_msg **result)
{
	struct nl_msg *msg;
	struct tcmsg tchdr = {
		.tcm_family = AF_UNSPEC,
		.tcm_ifindex = tca->tc_ifindex,
		.tcm_handle = tca->tc_handle,
		.tcm_parent = tca->tc_parent,
	};

	msg = nlmsg_alloc_simple(type, flags);
	if (!msg)
		return -NLE_NOMEM;

	if (nlmsg_append(msg, &tchdr, sizeof(tchdr), NLMSG_ALIGNTO) < 0)
		goto nla_put_failure;

	if (tca->ce_mask & TCA_ATTR_KIND)
	    NLA_PUT_STRING(msg, TCA_KIND, tca->tc_kind);

	*result = msg;
	return 0;

nla_put_failure:
	nlmsg_free(msg);
	return -NLE_MSGSIZE;
}

void tca_set_kind(struct rtnl_tc *t, const char *kind)
{
	strncpy(t->tc_kind, kind, sizeof(t->tc_kind) - 1);
	t->ce_mask |= TCA_ATTR_KIND;
}
Пример #2
0
static int veth_put_attrs(struct nl_msg *msg, struct rtnl_link *link)
{
	struct rtnl_link *peer = link->l_info;
	struct ifinfomsg ifi;
	struct nlattr *data, *info_peer;

	memset(&ifi, 0, sizeof ifi);
	ifi.ifi_family = peer->l_family;
	ifi.ifi_type = peer->l_arptype;
	ifi.ifi_index = peer->l_index;
	ifi.ifi_flags = peer->l_flags;
	ifi.ifi_change = peer->l_change;

	if (!(data = nla_nest_start(msg, IFLA_INFO_DATA)))
		return -NLE_MSGSIZE;
	if (!(info_peer = nla_nest_start(msg, VETH_INFO_PEER)))
		return -NLE_MSGSIZE;
	if (nlmsg_append(msg, &ifi, sizeof(ifi), NLMSG_ALIGNTO) < 0)
		return -NLE_MSGSIZE;
	rtnl_link_fill_info(msg, peer);
	nla_nest_end(msg, info_peer);
	nla_nest_end(msg, data);

	return 0;
}
static struct nl_msg *sfq_get_opts(struct rtnl_qdisc *qdisc)
{
	struct rtnl_sfq *sfq;
	struct tc_sfq_qopt opts;
	struct nl_msg *msg;

	sfq = sfq_qdisc(qdisc);
	if (!sfq)
		return NULL;

	msg = nlmsg_alloc();
	if (!msg)
		goto errout;

	memset(&opts, 0, sizeof(opts));
	opts.quantum = sfq->qs_quantum;
	opts.perturb_period = sfq->qs_perturb;
	opts.limit = sfq->qs_limit;

	if (nlmsg_append(msg, &opts, sizeof(opts), NL_DONTPAD) < 0)
		goto errout;

	return msg;
errout:
	nlmsg_free(msg);
	return NULL;
}
Пример #4
0
static struct nl_msg *fifo_get_opts(struct rtnl_qdisc *qdisc)
{
	struct rtnl_fifo *fifo;
	struct tc_fifo_qopt opts;
	struct nl_msg *msg;

	fifo = fifo_qdisc(qdisc);
	if (!fifo || !(fifo->qf_mask & SCH_FIFO_ATTR_LIMIT))
		return NULL;

	msg = nlmsg_build_no_hdr();
	if (!msg)
		goto errout;

	memset(&opts, 0, sizeof(opts));
	opts.limit = fifo->qf_limit;

	if (nlmsg_append(msg, &opts, sizeof(opts), 0) < 0)
		goto errout;

	return msg;
errout:
	nlmsg_free(msg);
	return NULL;
}
Пример #5
0
Файл: rule.c Проект: DINKIN/tuo
static struct nl_msg *build_rule_msg(struct rtnl_rule *tmpl, int cmd, int flags)
{
	struct nl_msg *msg;
	struct rtmsg rtm = {
		.rtm_type = RTN_UNSPEC
	};

	if (cmd == RTM_NEWRULE)
		rtm.rtm_type = RTN_UNICAST;
		
	if (tmpl->ce_mask & RULE_ATTR_FAMILY)
		rtm.rtm_family = tmpl->r_family;

	if (tmpl->ce_mask & RULE_ATTR_TABLE)
		rtm.rtm_table = tmpl->r_table;

	if (tmpl->ce_mask & RULE_ATTR_DSFIELD)
		rtm.rtm_tos = tmpl->r_dsfield;

	if (tmpl->ce_mask & RULE_ATTR_TYPE)
		rtm.rtm_type = tmpl->r_type;

	if (tmpl->ce_mask & RULE_ATTR_SRC_LEN)
		rtm.rtm_src_len = tmpl->r_src_len;

	if (tmpl->ce_mask & RULE_ATTR_DST_LEN)
		rtm.rtm_dst_len = tmpl->r_dst_len;

	msg = nlmsg_alloc_simple(cmd, flags);
	if (!msg)
		goto nla_put_failure;

	if (nlmsg_append(msg, &rtm, sizeof(rtm), NLMSG_ALIGNTO) < 0)
		goto nla_put_failure;

	if (tmpl->ce_mask & RULE_ATTR_SRC)
		NLA_PUT_ADDR(msg, RTA_SRC, tmpl->r_src);

	if (tmpl->ce_mask & RULE_ATTR_DST)
		NLA_PUT_ADDR(msg, RTA_DST, tmpl->r_dst);

	if (tmpl->ce_mask & RULE_ATTR_PRIO)
		NLA_PUT_U32(msg, RTA_PRIORITY, tmpl->r_prio);

	if (tmpl->ce_mask & RULE_ATTR_MARK)
		NLA_PUT_U32(msg, RTA_PROTOINFO, tmpl->r_mark);

	if (tmpl->ce_mask & RULE_ATTR_REALMS)
		NLA_PUT_U32(msg, RTA_FLOW, tmpl->r_realms);

	if (tmpl->ce_mask & RULE_ATTR_IIF)
		NLA_PUT_STRING(msg, RTA_IIF, tmpl->r_iif);

	return msg;

nla_put_failure:
	nlmsg_free(msg);
	return NULL;
}
Пример #6
0
/* return after DAD finishes for all known IPv6 addresses or an error */
int
virNetDevIPWaitDadFinish(virSocketAddrPtr *addrs, size_t count)
{
    struct nl_msg *nlmsg = NULL;
    struct ifaddrmsg ifa;
    struct nlmsghdr *resp = NULL;
    unsigned int recvbuflen;
    int ret = -1;
    bool dad = true;
    time_t max_time = time(NULL) + VIR_DAD_WAIT_TIMEOUT;

    if (!(nlmsg = nlmsg_alloc_simple(RTM_GETADDR,
                                     NLM_F_REQUEST | NLM_F_DUMP))) {
        virReportOOMError();
        return -1;
    }

    memset(&ifa, 0, sizeof(ifa));
    /* DAD is for IPv6 adresses only. */
    ifa.ifa_family = AF_INET6;
    if (nlmsg_append(nlmsg, &ifa, sizeof(ifa), NLMSG_ALIGNTO) < 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("allocated netlink buffer is too small"));
        goto cleanup;
    }

    /* Periodically query netlink until DAD finishes on all known addresses. */
    while (dad && time(NULL) < max_time) {
        if (virNetlinkCommand(nlmsg, &resp, &recvbuflen, 0, 0,
                              NETLINK_ROUTE, 0) < 0)
            goto cleanup;

        if (virNetlinkGetErrorCode(resp, recvbuflen) < 0) {
            virReportError(VIR_ERR_SYSTEM_ERROR, "%s",
                           _("error reading DAD state information"));
            goto cleanup;
        }

        /* Parse response. */
        dad = virNetDevIPParseDadStatus(resp, recvbuflen, addrs, count);
        if (dad)
            usleep(1000 * 10);

        VIR_FREE(resp);
    }
    /* Check timeout. */
    if (dad) {
        virReportError(VIR_ERR_SYSTEM_ERROR,
                       _("Duplicate Address Detection "
                         "not finished in %d seconds"), VIR_DAD_WAIT_TIMEOUT);
    } else {
        ret = 0;
    }

 cleanup:
    VIR_FREE(resp);
    nlmsg_free(nlmsg);
    return ret;
}
Пример #7
0
Файл: tc.c Проект: acooks/libnl
int rtnl_tc_msg_build(struct rtnl_tc *tc, int type, int flags,
		      struct nl_msg **result)
{
	struct nl_msg *msg;
	struct rtnl_tc_ops *ops;
	struct tcmsg tchdr = {
		.tcm_family = AF_UNSPEC,
		.tcm_ifindex = tc->tc_ifindex,
		.tcm_handle = tc->tc_handle,
		.tcm_parent = tc->tc_parent,
	};
	int err = -NLE_MSGSIZE;

	msg = nlmsg_alloc_simple(type, flags);
	if (!msg)
		return -NLE_NOMEM;

	if (nlmsg_append(msg, &tchdr, sizeof(tchdr), NLMSG_ALIGNTO) < 0)
		goto nla_put_failure;

	if (tc->ce_mask & TCA_ATTR_KIND)
	    NLA_PUT_STRING(msg, TCA_KIND, tc->tc_kind);

	ops = rtnl_tc_get_ops(tc);
	if (ops && (ops->to_msg_fill || ops->to_msg_fill_raw)) {
		struct nlattr *opts;
		void *data = rtnl_tc_data(tc);

		if (ops->to_msg_fill) {
			if (!(opts = nla_nest_start(msg, TCA_OPTIONS)))
				goto nla_put_failure;

			if ((err = ops->to_msg_fill(tc, data, msg)) < 0)
				goto nla_put_failure;

			nla_nest_end(msg, opts);
		} else if ((err = ops->to_msg_fill_raw(tc, data, msg)) < 0)
			goto nla_put_failure;
	}

	*result = msg;
	return 0;

nla_put_failure:
	nlmsg_free(msg);
	return err;
}

void tca_set_kind(struct rtnl_tc *t, const char *kind)
{
	strncpy(t->tc_kind, kind, sizeof(t->tc_kind) - 1);
	t->ce_mask |= TCA_ATTR_KIND;
}
Пример #8
0
TError TNlCgFilter::Create(const TNlLink &link) {
    TError error = TError::Success();
    struct nl_msg *msg;
    int ret;
	struct tcmsg tchdr;

    tchdr.tcm_family = AF_UNSPEC;
    tchdr.tcm_ifindex = link.GetIndex();
    tchdr.tcm_handle = Handle;
    tchdr.tcm_parent = Parent;
	tchdr.tcm_info = TC_H_MAKE(FilterPrio << 16, htons(ETH_P_ALL));

	msg = nlmsg_alloc_simple(RTM_NEWTFILTER, NLM_F_EXCL|NLM_F_CREATE);
	if (!msg)
        return TError(EError::Unknown, "Unable to add filter: no memory");

    ret = nlmsg_append(msg, &tchdr, sizeof(tchdr), NLMSG_ALIGNTO);
    if (ret < 0) {
        error = TError(EError::Unknown, std::string("Unable to add filter: ") + nl_geterror(ret));
		goto free_msg;
    }

    ret = nla_put(msg, TCA_KIND, strlen(FilterType) + 1, FilterType);
    if (ret < 0) {
        error = TError(EError::Unknown, std::string("Unable to add filter: ") + nl_geterror(ret));
		goto free_msg;
    }

    ret = nla_put(msg, TCA_OPTIONS, 0, NULL);
    if (ret < 0) {
        error = TError(EError::Unknown, std::string("Unable to add filter: ") + nl_geterror(ret));
		goto free_msg;
    }

    L() << "netlink " << link.GetDesc()
        << ": add tfilter id 0x" << std::hex << Handle
        << " parent 0x" << Parent << std::dec  << std::endl;

    ret = nl_send_sync(link.GetSock(), msg);
    if (ret)
        error = TError(EError::Unknown, std::string("Unable to add filter: ") + nl_geterror(ret));

    if (!Exists(link))
        error = TError(EError::Unknown, "BUG: created filter doesn't exist");

    return error;

free_msg:
    nlmsg_free(msg);

    return error;
}
Пример #9
0
int nl_dect_cell_build_msg(struct nl_msg *msg, struct nl_dect_cell *cell)
{
	struct dectmsg dm = {
		.dm_index	= cell->c_index,
	};

	if (nlmsg_append(msg, &dm, sizeof(dm), NLMSG_ALIGNTO) < 0)
		goto nla_put_failure;
	if (cell->ce_mask & CELL_ATTR_NAME)
		NLA_PUT_STRING(msg, DECTA_CELL_NAME, cell->c_name);
	if (cell->ce_mask & CELL_ATTR_FLAGS)
		NLA_PUT_U32(msg, DECTA_CELL_FLAGS, cell->c_flags);
	if (cell->ce_mask & CELL_ATTR_LINK)
		NLA_PUT_U8(msg, DECTA_CELL_CLUSTER, cell->c_link);
	return 0;

nla_put_failure:
	return -NLE_MSGSIZE;
}

static struct trans_tbl cell_flags[] = {
	__ADD(DECT_CELL_CCP,		ccp)
	__ADD(DECT_CELL_SLAVE,		slave)
	__ADD(DECT_CELL_MONITOR,	monitor)
};

char *nl_dect_cell_flags2str(uint32_t flags, char *buf, size_t len)
{
	return __flags2str(flags, buf, len, cell_flags, ARRAY_SIZE(cell_flags));
}

uint32_t nl_dect_cell_str2flags(const char *str)
{
	return __str2flags(str, cell_flags, ARRAY_SIZE(cell_flags));
}

/** @cond SKIP */
struct nl_object_ops nl_dect_cell_obj_ops = {
	.oo_name	= "nl_dect/cell",
	.oo_size	= sizeof(struct nl_dect_cell),
	.oo_free_data	= cell_free_data,
	.oo_dump	= {
		[NL_DUMP_LINE]	= cell_dump,
	},
	.oo_id_attrs	= CELL_ATTR_NAME,
Пример #10
0
static struct nl_msg * prepare_tcmsg(int type, int flags, uint32_t parent, uint32_t handle, uint32_t info) {
	struct nl_msg *msg = nlmsg_alloc_simple(type, flags);
	if (!msg)
		exit_errno("nlmsg_alloc_simple");

	struct tcmsg tcmsg;
	memset(&tcmsg, 0, sizeof(tcmsg));

	tcmsg.tcm_family = AF_UNSPEC;
	tcmsg.tcm_ifindex = ifindex;
	tcmsg.tcm_parent = parent;
	tcmsg.tcm_handle = handle;
	tcmsg.tcm_info = info;

	nlmsg_append(msg, &tcmsg, sizeof(tcmsg), NLMSG_ALIGNTO);

	return msg;
}
Пример #11
0
static int red_msg_fill(struct rtnl_tc *tc, void *data, struct nl_msg *msg)
{
	struct rtnl_red *red = data;

	if (!red)
		BUG();

#if 0
	memset(&opts, 0, sizeof(opts));
	opts.quantum = sfq->qs_quantum;
	opts.perturb_period = sfq->qs_perturb;
	opts.limit = sfq->qs_limit;

	if (nlmsg_append(msg, &opts, sizeof(opts), NL_DONTPAD) < 0)
		goto errout;
#endif

	return -NLE_OPNOTSUPP;
}
Пример #12
0
/**
 * Builds a netlink request message to do a lookup
 * @arg req		Requested match.
 * @arg flags		additional netlink message flags
 * @arg result		Result pointer
 *
 * 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 0 on success or a negative error code.
 */
int flnl_lookup_build_request(struct flnl_request *req, int flags,
			      struct nl_msg **result)
{
	struct nl_msg *msg;
	struct nl_addr *addr;
	uint64_t fwmark;
	int tos, scope, table;
	struct fib_result_nl fr = {0};

	fwmark = flnl_request_get_fwmark(req);
	tos = flnl_request_get_tos(req);
	scope = flnl_request_get_scope(req);
	table = flnl_request_get_table(req);

	fr.fl_fwmark = fwmark != UINT_LEAST64_MAX ? fwmark : 0;
	fr.fl_tos = tos >= 0 ? tos : 0;
	fr.fl_scope = scope >= 0 ? scope : RT_SCOPE_UNIVERSE;
	fr.tb_id_in = table >= 0 ? table : RT_TABLE_UNSPEC;

	addr = flnl_request_get_addr(req);
	if (!addr)
		return -NLE_MISSING_ATTR;

	fr.fl_addr = *(uint32_t *) nl_addr_get_binary_addr(addr);

	msg = nlmsg_alloc_simple(0, flags);
	if (!msg)
		return -NLE_NOMEM;

	if (nlmsg_append(msg, &fr, sizeof(fr), NLMSG_ALIGNTO) < 0)
		goto errout;

	*result = msg;
	return 0;

errout:
	nlmsg_free(msg);
	return -NLE_MSGSIZE;
}
Пример #13
0
/**
 * Builds a netlink request message to do a lookup
 * @arg req		Requested match.
 * @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 *flnl_lookup_build_request(struct flnl_request *req, int flags)
{
	struct nl_msg *msg;
	struct nl_addr *addr;
	uint64_t fwmark;
	int tos, scope, table;
	struct fib_result_nl fr = {0};

	fwmark = flnl_request_get_fwmark(req);
	tos = flnl_request_get_tos(req);
	scope = flnl_request_get_scope(req);
	table = flnl_request_get_table(req);

	fr.fl_fwmark = fwmark != UINT_LEAST64_MAX ? fwmark : 0;
	fr.fl_tos = tos >= 0 ? tos : 0;
	fr.fl_scope = scope >= 0 ? scope : RT_SCOPE_UNIVERSE;
	fr.tb_id_in = table >= 0 ? table : RT_TABLE_UNSPEC;

	addr = flnl_request_get_addr(req);
	if (!addr) {
		nl_error(EINVAL, "Request must specify the address");
		return NULL;
	}

	fr.fl_addr = *(uint32_t *) nl_addr_get_binary_addr(addr);

	msg = nlmsg_alloc_simple(0, flags);
	if (!msg)
		goto errout;

	if (nlmsg_append(msg, &fr, sizeof(fr), NLMSG_ALIGNTO) < 0)
		goto errout;

	return msg;

errout:
	nlmsg_free(msg);
	return NULL;
}
Пример #14
0
/**
 * Construct and transmit a Netlink message
 * @arg sk		Netlink socket (required)
 * @arg type		Netlink message type (required)
 * @arg flags		Netlink message flags (optional)
 * @arg buf		Data buffer (optional)
 * @arg size		Size of data buffer (optional)
 *
 * Allocates a new Netlink message based on `type` and `flags`. If `buf`
 * points to payload of length `size` that payload will be appended to the
 * message.
 *
 * Sends out the message using `nl_send_auto()` and frees the message
 * afterwards.
 *
 * @see nl_send_auto()
 *
 * @return Number of characters sent on success or a negative error code.
 * @retval -NLE_NOMEM Unable to allocate Netlink message
 */
int nl_send_simple(struct nl_sock *sk, int type, int flags, void *buf,
                   size_t size)
{
    int err;
    struct nl_msg *msg;

    msg = nlmsg_alloc_simple(type, flags);
    if (!msg)
        return -NLE_NOMEM;

    if (buf && size) {
        err = nlmsg_append(msg, buf, size, NLMSG_ALIGNTO);
        if (err < 0)
            goto errout;
    }

    err = nl_send_auto(sk, msg);
errout:
    nlmsg_free(msg);

    return err;
}
Пример #15
0
Файл: ae.c Проект: Domikk/libnl
int xfrmnl_ae_build_get_request(struct nl_addr* daddr, unsigned int spi, unsigned int protocol,
                                unsigned int mark_mask, unsigned int mark_value, struct nl_msg **result)
{
	struct nl_msg *msg;
	struct xfrm_aevent_id   ae_id;
	struct xfrmnl_mark   mark;

	if (!daddr || !spi)
	{
		fprintf(stderr, "APPLICATION BUG: %s:%d:%s: A valid destination address, spi must be specified\n",
				__FILE__, __LINE__, __PRETTY_FUNCTION__);
		assert(0);
		return -NLE_MISSING_ATTR;
	}

	memset(&ae_id, 0, sizeof(ae_id));
	memcpy (&ae_id.sa_id.daddr, nl_addr_get_binary_addr (daddr), sizeof (uint8_t) * nl_addr_get_len (daddr));
	ae_id.sa_id.spi    = htonl(spi);
	ae_id.sa_id.family = nl_addr_get_family (daddr);
	ae_id.sa_id.proto  = protocol;

	if (!(msg = nlmsg_alloc_simple(XFRM_MSG_GETAE, 0)))
		return -NLE_NOMEM;

	if (nlmsg_append(msg, &ae_id, sizeof(ae_id), NLMSG_ALIGNTO) < 0)
		goto nla_put_failure;

	mark.m  =   mark_mask;
	mark.v  =   mark_value;
	NLA_PUT (msg, XFRMA_MARK, sizeof (struct xfrmnl_mark), &mark);

	*result = msg;
	return 0;

nla_put_failure:
	nlmsg_free(msg);
	return -NLE_MSGSIZE;
}
Пример #16
0
static struct nl_msg *build_addr_msg(struct rtnl_addr *tmpl, int cmd, int flags)
{
	struct nl_msg *msg;
	struct ifaddrmsg am = {
		.ifa_family = tmpl->a_family,
		.ifa_index = tmpl->a_ifindex,
		.ifa_prefixlen = tmpl->a_prefixlen,
	};

	if (tmpl->a_mask & ADDR_ATTR_FLAGS)
		am.ifa_flags = tmpl->a_flags;

	if (tmpl->a_mask & ADDR_ATTR_SCOPE)
		am.ifa_scope = tmpl->a_scope;
	else {
		/* compatibility hack */
		if (tmpl->a_family == AF_INET &&
		    tmpl->a_mask & ADDR_ATTR_LOCAL &&
		    *((char *) nl_addr_get_binary_addr(tmpl->a_local)) == 127)
			am.ifa_scope = RT_SCOPE_HOST;
		else
			am.ifa_scope = RT_SCOPE_UNIVERSE;
	}

	msg = nlmsg_build_simple(cmd, flags);
	if (!msg)
		goto nla_put_failure;

	if (nlmsg_append(msg, &am, sizeof(am), 1) < 0)
		goto nla_put_failure;

	if (tmpl->a_mask & ADDR_ATTR_LOCAL)
		NLA_PUT_ADDR(msg, IFA_LOCAL, tmpl->a_local);

	if (tmpl->a_mask & ADDR_ATTR_PEER)
		NLA_PUT_ADDR(msg, IFA_ADDRESS, tmpl->a_peer);
	else
		NLA_PUT_ADDR(msg, IFA_ADDRESS, tmpl->a_local);

	if (tmpl->a_mask & ADDR_ATTR_LABEL)
		NLA_PUT_STRING(msg, IFA_LABEL, tmpl->a_label);

	if (tmpl->a_mask & ADDR_ATTR_BROADCAST)
		NLA_PUT_ADDR(msg, IFA_BROADCAST, tmpl->a_bcast);

	if (tmpl->a_mask & ADDR_ATTR_ANYCAST)
		NLA_PUT_ADDR(msg, IFA_ANYCAST, tmpl->a_anycast);

	return msg;

nla_put_failure:
	nlmsg_free(msg);
	return NULL;
}

/**
 * @name Address Addition
 * @{
 */

/**
 * Build netlink request message to request addition of new address
 * @arg addr		Address object representing the new address.
 * @arg flags		Additional netlink message flags.
 *
 * Builds a new netlink message requesting the addition of a new
 * address. The netlink message header isn't fully equipped with
 * all relevant fields and must thus be sent out via nl_send_auto_complete()
 * or supplemented as needed.
 *
 * Minimal required attributes:
 *   - interface index (rtnl_addr_set_ifindex())
 *   - local address (rtnl_addr_set_local())
 *
 * The scope will default to universe except for loopback addresses in
 * which case a host scope is used if not specified otherwise.
 *
 * @note Free the memory after usage using nlmsg_free().
 * @return Newly allocated netlink message or NULL if an error occured.
 */
struct nl_msg *rtnl_addr_build_add_request(struct rtnl_addr *addr, int flags)
{
	int required = ADDR_ATTR_IFINDEX | ADDR_ATTR_FAMILY |
		       ADDR_ATTR_PREFIXLEN | ADDR_ATTR_LOCAL;

	if ((addr->a_mask & required) != required) {
		nl_error(EINVAL, "Missing mandatory attributes, required are: "
				 "ifindex, family, prefixlen, local address.");
		return NULL;
	}
	
	return build_addr_msg(addr, RTM_NEWADDR, NLM_F_CREATE | flags);
}
Пример #17
0
/**
 * virNetlinkCommand:
 * @nlmsg: pointer to netlink message
 * @respbuf: pointer to pointer where response buffer will be allocated
 * @respbuflen: pointer to integer holding the size of the response buffer
 *      on return of the function.
 * @src_pid: the pid of the process to send a message
 * @dst_pid: the pid of the process to talk to, i.e., pid = 0 for kernel
 * @protocol: netlink protocol
 * @groups: the group identifier
 *
 * Send the given message to the netlink layer and receive response.
 * Returns 0 on success, -1 on error. In case of error, no response
 * buffer will be returned.
 */
int virNetlinkCommand(struct nl_msg *nl_msg,
                      struct nlmsghdr **resp, unsigned int *respbuflen,
                      uint32_t src_pid, uint32_t dst_pid,
                      unsigned int protocol, unsigned int groups)
{
    int ret = -1;
    struct sockaddr_nl nladdr = {
            .nl_family = AF_NETLINK,
            .nl_pid    = dst_pid,
            .nl_groups = 0,
    };
    ssize_t nbytes;
    struct pollfd fds[1];
    int fd;
    int n;
    struct nlmsghdr *nlmsg = nlmsg_hdr(nl_msg);
    virNetlinkHandle *nlhandle = NULL;
    int len = 0;

    if (protocol >= MAX_LINKS) {
        virReportSystemError(EINVAL,
                             _("invalid protocol argument: %d"), protocol);
        goto cleanup;
    }

    if (!(nlhandle = virNetlinkCreateSocket(protocol)))
        goto cleanup;

    fd = nl_socket_get_fd(nlhandle);
    if (fd < 0) {
        virReportSystemError(errno,
                             "%s", _("cannot get netlink socket fd"));
        goto cleanup;
    }

    if (groups && nl_socket_add_membership(nlhandle, groups) < 0) {
        virReportSystemError(errno,
                             "%s", _("cannot add netlink membership"));
        goto cleanup;
    }

    nlmsg_set_dst(nl_msg, &nladdr);

    nlmsg->nlmsg_pid = src_pid ? src_pid : getpid();

    nbytes = nl_send_auto_complete(nlhandle, nl_msg);
    if (nbytes < 0) {
        virReportSystemError(errno,
                             "%s", _("cannot send to netlink socket"));
        goto cleanup;
    }

    memset(fds, 0, sizeof(fds));
    fds[0].fd = fd;
    fds[0].events = POLLIN;

    n = poll(fds, ARRAY_CARDINALITY(fds), NETLINK_ACK_TIMEOUT_S);
    if (n <= 0) {
        if (n < 0)
            virReportSystemError(errno, "%s",
                                 _("error in poll call"));
        if (n == 0)
            virReportSystemError(ETIMEDOUT, "%s",
                                 _("no valid netlink response was received"));
        goto cleanup;
    }

    len = nl_recv(nlhandle, &nladdr, (unsigned char **)resp, NULL);
    if (len == 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("nl_recv failed - returned 0 bytes"));
        goto cleanup;
    }
    if (len < 0) {
        virReportSystemError(errno, "%s", _("nl_recv failed"));
        goto cleanup;
    }

    ret = 0;
    *respbuflen = len;
 cleanup:
    if (ret < 0) {
        *resp = NULL;
        *respbuflen = 0;
    }

    virNetlinkFree(nlhandle);
    return ret;
}


/**
 * virNetlinkDumpLink:
 *
 * @ifname:  The name of the interface; only use if ifindex <= 0
 * @ifindex: The interface index; may be <= 0 if ifname is given
 * @data:    Gets a pointer to the raw data from netlink.
             MUST BE FREED BY CALLER!
 * @nlattr:  Pointer to a pointer of netlink attributes that will contain
 *           the results
 * @src_pid: pid used for nl_pid of the local end of the netlink message
 *           (0 == "use getpid()")
 * @dst_pid: pid of destination nl_pid if the kernel
 *           is not the target of the netlink message but it is to be
 *           sent to another process (0 if sending to the kernel)
 *
 * Get information from netlink about an interface given its name or index.
 *
 * Returns 0 on success, -1 on fatal error.
 */
int
virNetlinkDumpLink(const char *ifname, int ifindex,
                   void **nlData, struct nlattr **tb,
                   uint32_t src_pid, uint32_t dst_pid)
{
    int rc = -1;
    struct nlmsghdr *resp = NULL;
    struct nlmsgerr *err;
    struct ifinfomsg ifinfo = {
        .ifi_family = AF_UNSPEC,
        .ifi_index  = ifindex
    };
    unsigned int recvbuflen;
    struct nl_msg *nl_msg;

    if (ifname && ifindex <= 0 && virNetDevGetIndex(ifname, &ifindex) < 0)
        return -1;

    ifinfo.ifi_index = ifindex;

    nl_msg = nlmsg_alloc_simple(RTM_GETLINK, NLM_F_REQUEST);
    if (!nl_msg) {
        virReportOOMError();
        return -1;
    }

    if (nlmsg_append(nl_msg,  &ifinfo, sizeof(ifinfo), NLMSG_ALIGNTO) < 0)
        goto buffer_too_small;

    if (ifname) {
        if (nla_put(nl_msg, IFLA_IFNAME, strlen(ifname)+1, ifname) < 0)
            goto buffer_too_small;
    }

# ifdef RTEXT_FILTER_VF
    /* if this filter exists in the kernel's netlink implementation,
     * we need to set it, otherwise the response message will not
     * contain the IFLA_VFINFO_LIST that we're looking for.
     */
    {
        uint32_t ifla_ext_mask = RTEXT_FILTER_VF;

        if (nla_put(nl_msg, IFLA_EXT_MASK,
                    sizeof(ifla_ext_mask), &ifla_ext_mask) < 0) {
            goto buffer_too_small;
        }
    }
# endif

    if (virNetlinkCommand(nl_msg, &resp, &recvbuflen,
                          src_pid, dst_pid, NETLINK_ROUTE, 0) < 0)
        goto cleanup;

    if (recvbuflen < NLMSG_LENGTH(0) || resp == NULL)
        goto malformed_resp;

    switch (resp->nlmsg_type) {
    case NLMSG_ERROR:
        err = (struct nlmsgerr *)NLMSG_DATA(resp);
        if (resp->nlmsg_len < NLMSG_LENGTH(sizeof(*err)))
            goto malformed_resp;

        if (err->error) {
            virReportSystemError(-err->error,
                                 _("error dumping %s (%d) interface"),
                                 ifname, ifindex);
            goto cleanup;
        }
        break;

    case GENL_ID_CTRL:
    case NLMSG_DONE:
        rc = nlmsg_parse(resp, sizeof(struct ifinfomsg),
                         tb, IFLA_MAX, NULL);
        if (rc < 0)
            goto malformed_resp;
        break;

    default:
        goto malformed_resp;
    }
    rc = 0;
 cleanup:
    nlmsg_free(nl_msg);
    if (rc < 0)
       VIR_FREE(resp);
    *nlData = resp;
    return rc;

 malformed_resp:
    virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                   _("malformed netlink response message"));
    goto cleanup;

 buffer_too_small:
    virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                   _("allocated netlink buffer is too small"));
    goto cleanup;
}
Пример #18
0
int ompi_btl_usnic_nl_ip_rt_lookup(struct usnic_rtnl_sk *unlsk,
                                   const char *src_ifname,
                                   uint32_t src_addr,
                                   uint32_t dst_addr, int *metric)
{
	struct nl_msg 		*nlm;
	struct rtmsg 		rmsg;
	struct nl_lookup_arg    arg;
	int	msg_cnt;
	int		     	err;
	int oif;

	oif = if_nametoindex(src_ifname);
	if (0 == oif) {
	    return errno;
	}

	arg.nh_addr 	= 0;
	arg.oif		= oif;
	arg.found	= 0;
	arg.replied	= 0;
	arg.unlsk	= unlsk;
	arg.msg_count = msg_cnt = 0;

	memset(&rmsg, 0, sizeof(rmsg));
	rmsg.rtm_family = AF_INET;
	rmsg.rtm_dst_len = sizeof(dst_addr)*8;
	rmsg.rtm_src_len = sizeof(src_addr)*8;

	nlm = nlmsg_alloc_simple(RTM_GETROUTE, 0);
	nlmsg_append(nlm, &rmsg, sizeof(rmsg), NLMSG_ALIGNTO);
	nla_put_u32(nlm, RTA_DST, dst_addr);
	nla_put_u32(nlm, RTA_SRC, src_addr);

	err = rtnl_send_ack_disable(unlsk, nlm);
	nlmsg_free(nlm);
	if (err < 0) {
		usnic_err("Failed to send rtnl query %s\n", nl_geterror(err));
		return err;
	}

	err = nl_socket_modify_cb(unlsk->sock, NL_CB_MSG_IN, NL_CB_CUSTOM,
					rtnl_raw_parse_cb, &arg);
	if (err != 0) {
		usnic_err("Failed to setup callback function, error %s\n",
				nl_geterror(err));
		return err;
	}

	while (!arg.replied) {
		err = nl_recvmsgs_default(unlsk->sock);
		if (err < 0) {
			/* err will be returned as -NLE_AGAIN if the socket times out */
			usnic_err("Failed to receive rtnl query results %s\n",
					nl_geterror(err));
			return err;
		}
	}

	if (arg.found) {
                if (metric != NULL) {
                    *metric = arg.metric;
                }
		return 0;
	}
	else {
		return -1;
	}
}
Пример #19
0
static struct nl_msg *
virNetDevCreateNetlinkAddressMessage(int messageType,
                                     const char *ifname,
                                     virSocketAddr *addr,
                                     unsigned int prefix,
                                     virSocketAddr *broadcast,
                                     virSocketAddr *peer)
{
    struct nl_msg *nlmsg = NULL;
    struct ifaddrmsg ifa;
    unsigned int ifindex;
    void *addrData = NULL;
    void *peerData = NULL;
    void *broadcastData = NULL;
    size_t addrDataLen;

    if (virNetDevGetIPAddressBinary(addr, &addrData, &addrDataLen) < 0)
        return NULL;

    if (peer && VIR_SOCKET_ADDR_VALID(peer)) {
        if (virNetDevGetIPAddressBinary(peer, &peerData, &addrDataLen) < 0)
            return NULL;
    } else if (broadcast) {
        if (virNetDevGetIPAddressBinary(broadcast, &broadcastData,
                                        &addrDataLen) < 0)
            return NULL;
    }

    /* Get the interface index */
    if ((ifindex = if_nametoindex(ifname)) == 0)
        return NULL;

    if (!(nlmsg = nlmsg_alloc_simple(messageType,
                                     NLM_F_REQUEST | NLM_F_CREATE | NLM_F_EXCL))) {
        virReportOOMError();
        return NULL;
    }

    memset(&ifa, 0, sizeof(ifa));

    ifa.ifa_prefixlen = prefix;
    ifa.ifa_family = VIR_SOCKET_ADDR_FAMILY(addr);
    ifa.ifa_index = ifindex;
    ifa.ifa_scope = 0;

    if (nlmsg_append(nlmsg, &ifa, sizeof(ifa), NLMSG_ALIGNTO) < 0)
        goto buffer_too_small;

    if (nla_put(nlmsg, IFA_LOCAL, addrDataLen, addrData) < 0)
        goto buffer_too_small;

    if (peerData) {
        if (nla_put(nlmsg, IFA_ADDRESS, addrDataLen, peerData) < 0)
            goto buffer_too_small;
    }

    if (broadcastData) {
        if (nla_put(nlmsg, IFA_BROADCAST, addrDataLen, broadcastData) < 0)
            goto buffer_too_small;
    }

    return nlmsg;

 buffer_too_small:
    virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                   _("allocated netlink buffer is too small"));
    nlmsg_free(nlmsg);
    return NULL;
}
Пример #20
0
/**
 * virNetDevIPRouteAdd:
 * @ifname: the interface name
 * @addr: the IP network address (IPv4 or IPv6)
 * @prefix: number of 1 bits in the netmask
 * @gateway: via address for route (same as @addr)
 *
 * Add a route for a network IP address to an interface. This function
 * *does not* remove any previously added IP static routes.
 *
 * Returns 0 in case of success or -1 in case of error.
 */
int
virNetDevIPRouteAdd(const char *ifname,
                    virSocketAddrPtr addr,
                    unsigned int prefix,
                    virSocketAddrPtr gateway,
                    unsigned int metric)
{
    int ret = -1;
    struct nl_msg *nlmsg = NULL;
    struct nlmsghdr *resp = NULL;
    unsigned int recvbuflen;
    unsigned int ifindex;
    struct rtmsg rtmsg;
    void *gatewayData = NULL;
    void *addrData = NULL;
    size_t addrDataLen;
    int errCode;
    virSocketAddr defaultAddr;
    virSocketAddrPtr actualAddr;
    char *toStr = NULL;
    char *viaStr = NULL;

    actualAddr = addr;

    /* If we have no valid network address, then use the default one */
    if (!addr || !VIR_SOCKET_ADDR_VALID(addr)) {
        VIR_DEBUG("computing default address");
        int family = VIR_SOCKET_ADDR_FAMILY(gateway);
        if (family == AF_INET) {
            if (virSocketAddrParseIPv4(&defaultAddr, VIR_SOCKET_ADDR_IPV4_ALL) < 0)
                goto cleanup;
        } else {
            if (virSocketAddrParseIPv6(&defaultAddr, VIR_SOCKET_ADDR_IPV6_ALL) < 0)
                goto cleanup;
        }

        actualAddr = &defaultAddr;
    }

    toStr = virSocketAddrFormat(actualAddr);
    viaStr = virSocketAddrFormat(gateway);
    VIR_DEBUG("Adding route %s/%d via %s", toStr, prefix, viaStr);

    if (virNetDevGetIPAddressBinary(actualAddr, &addrData, &addrDataLen) < 0 ||
        virNetDevGetIPAddressBinary(gateway, &gatewayData, &addrDataLen) < 0)
        goto cleanup;

    /* Get the interface index */
    if ((ifindex = if_nametoindex(ifname)) == 0)
        goto cleanup;

    if (!(nlmsg = nlmsg_alloc_simple(RTM_NEWROUTE,
                                     NLM_F_REQUEST | NLM_F_CREATE |
                                     NLM_F_EXCL))) {
        virReportOOMError();
        goto cleanup;
    }

    memset(&rtmsg, 0, sizeof(rtmsg));

    rtmsg.rtm_family = VIR_SOCKET_ADDR_FAMILY(gateway);
    rtmsg.rtm_table = RT_TABLE_MAIN;
    rtmsg.rtm_scope = RT_SCOPE_UNIVERSE;
    rtmsg.rtm_protocol = RTPROT_BOOT;
    rtmsg.rtm_type = RTN_UNICAST;
    rtmsg.rtm_dst_len = prefix;

    if (nlmsg_append(nlmsg, &rtmsg, sizeof(rtmsg), NLMSG_ALIGNTO) < 0)
        goto buffer_too_small;

    if (prefix > 0 && nla_put(nlmsg, RTA_DST, addrDataLen, addrData) < 0)
        goto buffer_too_small;

    if (nla_put(nlmsg, RTA_GATEWAY, addrDataLen, gatewayData) < 0)
        goto buffer_too_small;

    if (nla_put_u32(nlmsg, RTA_OIF, ifindex) < 0)
        goto buffer_too_small;

    if (metric > 0 && nla_put_u32(nlmsg, RTA_PRIORITY, metric) < 0)
        goto buffer_too_small;

    if (virNetlinkCommand(nlmsg, &resp, &recvbuflen, 0, 0,
                          NETLINK_ROUTE, 0) < 0)
        goto cleanup;

    if ((errCode = virNetlinkGetErrorCode(resp, recvbuflen)) < 0) {
        virReportSystemError(errCode, _("Error adding route to %s"), ifname);
        goto cleanup;
    }

    ret = 0;
 cleanup:
    VIR_FREE(toStr);
    VIR_FREE(viaStr);
    nlmsg_free(nlmsg);
    return ret;

 buffer_too_small:
    virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                   _("allocated netlink buffer is too small"));
    goto cleanup;
}
static void copy_cacheinfo_into_route(struct rta_cacheinfo *ci,
				      struct rtnl_route *route)
{
	struct rtnl_rtcacheinfo nci = {
		.rtci_clntref  = ci->rta_clntref,
		.rtci_last_use = ci->rta_lastuse,
		.rtci_expires  = ci->rta_expires,
		.rtci_error    = ci->rta_error,
		.rtci_used     = ci->rta_used,
		.rtci_id       = ci->rta_id,
		.rtci_ts       = ci->rta_ts,
		.rtci_tsage    = ci->rta_tsage,
	};

	rtnl_route_set_cacheinfo(route, &nci);
}

static int route_msg_parser(struct nl_cache_ops *ops, struct sockaddr_nl *who,
			    struct nlmsghdr *nlh, struct nl_parser_param *pp)
{
	struct rtmsg *rtm;
	struct rtnl_route *route;
	struct nlattr *tb[RTA_MAX + 1];
	struct nl_addr *src = NULL, *dst = NULL, *addr;
	int err;

	route = rtnl_route_alloc();
	if (!route) {
		err = nl_errno(ENOMEM);
		goto errout;
	}

	route->ce_msgtype = nlh->nlmsg_type;

	err = nlmsg_parse(nlh, sizeof(struct rtmsg), tb, RTA_MAX,
			  route_policy);
	if (err < 0)
		goto errout;

	rtm = nlmsg_data(nlh);
	rtnl_route_set_family(route, rtm->rtm_family);
	rtnl_route_set_tos(route, rtm->rtm_tos);
	rtnl_route_set_table(route, rtm->rtm_table);
	rtnl_route_set_type(route, rtm->rtm_type);
	rtnl_route_set_scope(route, rtm->rtm_scope);
	rtnl_route_set_protocol(route, rtm->rtm_protocol);
	rtnl_route_set_flags(route, rtm->rtm_flags);

	if (tb[RTA_DST]) {
		dst = nla_get_addr(tb[RTA_DST], rtm->rtm_family);
		if (dst == NULL)
			goto errout_errno;
	} else {
		dst = nl_addr_alloc(0);
		nl_addr_set_family(dst, rtm->rtm_family);
	}

	nl_addr_set_prefixlen(dst, rtm->rtm_dst_len);
	err = rtnl_route_set_dst(route, dst);
	if (err < 0)
		goto errout;

	nl_addr_put(dst);

	if (tb[RTA_SRC]) {
		src = nla_get_addr(tb[RTA_SRC], rtm->rtm_family);
		if (src == NULL)
			goto errout_errno;
	} else if (rtm->rtm_src_len)
		src = nl_addr_alloc(0);

	if (src) {
		nl_addr_set_prefixlen(src, rtm->rtm_src_len);
		rtnl_route_set_src(route, src);
		nl_addr_put(src);
	}

	if (tb[RTA_IIF])
		rtnl_route_set_iif(route, nla_get_string(tb[RTA_IIF]));

	if (tb[RTA_OIF])
		rtnl_route_set_oif(route, nla_get_u32(tb[RTA_OIF]));

	if (tb[RTA_GATEWAY]) {
		addr = nla_get_addr(tb[RTA_GATEWAY], route->rt_family);
		if (addr == NULL)
			goto errout_errno;
		rtnl_route_set_gateway(route, addr);
		nl_addr_put(addr);
	}

	if (tb[RTA_PRIORITY])
		rtnl_route_set_prio(route, nla_get_u32(tb[RTA_PRIORITY]));

	if (tb[RTA_PREFSRC]) {
		addr = nla_get_addr(tb[RTA_PREFSRC], route->rt_family);
		if (addr == NULL)
			goto errout_errno;
		rtnl_route_set_pref_src(route, addr);
		nl_addr_put(addr);
	}

	if (tb[RTA_METRICS]) {
		struct nlattr *mtb[RTAX_MAX + 1];
		int i;

		err = nla_parse_nested(mtb, RTAX_MAX, tb[RTA_METRICS], NULL);
		if (err < 0)
			goto errout;

		for (i = 1; i <= RTAX_MAX; i++) {
			if (mtb[i] && nla_len(mtb[i]) >= sizeof(uint32_t)) {
				uint32_t m = nla_get_u32(mtb[i]);
				if (rtnl_route_set_metric(route, i, m) < 0)
					goto errout_errno;
			}
		}
	}

	if (tb[RTA_MULTIPATH]) {
		struct rtnl_nexthop *nh;
		struct rtnexthop *rtnh = nla_data(tb[RTA_MULTIPATH]);
		size_t tlen = nla_len(tb[RTA_MULTIPATH]);

		while (tlen >= sizeof(*rtnh) && tlen >= rtnh->rtnh_len) {
			nh = rtnl_route_nh_alloc();
			if (!nh)
				goto errout;

			rtnl_route_nh_set_weight(nh, rtnh->rtnh_hops);
			rtnl_route_nh_set_ifindex(nh, rtnh->rtnh_ifindex);
			rtnl_route_nh_set_flags(nh, rtnh->rtnh_flags);

			if (rtnh->rtnh_len > sizeof(*rtnh)) {
				struct nlattr *ntb[RTA_MAX + 1];
				nla_parse(ntb, RTA_MAX, (struct nlattr *)
					  RTNH_DATA(rtnh),
					  rtnh->rtnh_len - sizeof(*rtnh),
					  route_policy);

				if (ntb[RTA_GATEWAY]) {
					nh->rtnh_gateway = nla_get_addr(
							ntb[RTA_GATEWAY],
							route->rt_family);
					nh->rtnh_mask = NEXTHOP_HAS_GATEWAY;
				}
			}

			rtnl_route_add_nexthop(route, nh);
			tlen -= RTNH_ALIGN(rtnh->rtnh_len);
			rtnh = RTNH_NEXT(rtnh);
		}
	}

	if (tb[RTA_FLOW])
		rtnl_route_set_realms(route, nla_get_u32(tb[RTA_FLOW]));

	if (tb[RTA_CACHEINFO])
		copy_cacheinfo_into_route(nla_data(tb[RTA_CACHEINFO]), route);

	if (tb[RTA_MP_ALGO])
		rtnl_route_set_mp_algo(route, nla_get_u32(tb[RTA_MP_ALGO]));

	err = pp->pp_cb((struct nl_object *) route, pp);
	if (err < 0)
		goto errout;

	err = P_ACCEPT;

errout:
	rtnl_route_put(route);
	return err;

errout_errno:
	err = nl_get_errno();
	goto errout;
}

static int route_request_update(struct nl_cache *c, struct nl_handle *h)
{
	return nl_rtgen_request(h, RTM_GETROUTE, AF_UNSPEC, NLM_F_DUMP);
}

/**
 * @name Cache Management
 * @{
 */

/**
 * Build a route cache holding all routes currently configured in the kernel
 * @arg handle		netlink handle
 *
 * Allocates a new cache, initializes it properly and updates it to
 * contain all routes currently configured in the kernel.
 *
 * @note The caller is responsible for destroying and freeing the
 *       cache after using it.
 * @return The cache or NULL if an error has occured.
 */
struct nl_cache *rtnl_route_alloc_cache(struct nl_handle *handle)
{
	struct nl_cache *cache;

	cache = nl_cache_alloc(&rtnl_route_ops);
	if (!cache)
		return NULL;

	if (handle && nl_cache_refill(handle, cache) < 0) {
		free(cache);
		return NULL;
	}

	return cache;
}

/** @} */

/**
 * @name Route Addition
 * @{
 */

static struct nl_msg *build_route_msg(struct rtnl_route *tmpl, int cmd,
				      int flags)
{
	struct nl_msg *msg;
	struct nl_addr *addr;
	int scope, i, oif, nmetrics = 0;
	struct nlattr *metrics;
	struct rtmsg rtmsg = {
		.rtm_family = rtnl_route_get_family(tmpl),
		.rtm_dst_len = rtnl_route_get_dst_len(tmpl),
		.rtm_src_len = rtnl_route_get_src_len(tmpl),
		.rtm_tos = rtnl_route_get_tos(tmpl),
		.rtm_table = rtnl_route_get_table(tmpl),
		.rtm_type = rtnl_route_get_type(tmpl),
		.rtm_protocol = rtnl_route_get_protocol(tmpl),
		.rtm_flags = rtnl_route_get_flags(tmpl),
	};

	if (rtmsg.rtm_family == AF_UNSPEC) {
		nl_error(EINVAL, "Cannot build route message, address " \
				 "family is unknown.");
		return NULL;
	}

	scope = rtnl_route_get_scope(tmpl);
	if (scope == RT_SCOPE_NOWHERE) {
		if (rtmsg.rtm_type == RTN_LOCAL)
			scope = RT_SCOPE_HOST;
		else {
			/* XXX Change to UNIVERSE if gw || nexthops */
			scope = RT_SCOPE_LINK;
		}
	}

	rtmsg.rtm_scope = scope;

	msg = nlmsg_alloc_simple(cmd, flags);
	if (msg == NULL)
		return NULL;

	if (nlmsg_append(msg, &rtmsg, sizeof(rtmsg), NLMSG_ALIGNTO) < 0)
		goto nla_put_failure;

	addr = rtnl_route_get_dst(tmpl);
	if (addr)
		NLA_PUT_ADDR(msg, RTA_DST, addr);

	addr = rtnl_route_get_src(tmpl);
	if (addr)
		NLA_PUT_ADDR(msg, RTA_SRC, addr);

	addr = rtnl_route_get_gateway(tmpl);
	if (addr)
		NLA_PUT_ADDR(msg, RTA_GATEWAY, addr);

	addr = rtnl_route_get_pref_src(tmpl);
	if (addr)
		NLA_PUT_ADDR(msg, RTA_PREFSRC, addr);

	NLA_PUT_U32(msg, RTA_PRIORITY, rtnl_route_get_prio(tmpl));

	oif = rtnl_route_get_oif(tmpl);
	if (oif != RTNL_LINK_NOT_FOUND)
		NLA_PUT_U32(msg, RTA_OIF, oif);

	for (i = 1; i <= RTAX_MAX; i++)
		if (rtnl_route_get_metric(tmpl, i) != UINT_MAX)
			nmetrics++;

	if (nmetrics > 0) {
		unsigned int val;

		metrics = nla_nest_start(msg, RTA_METRICS);
		if (metrics == NULL)
			goto nla_put_failure;

		for (i = 1; i <= RTAX_MAX; i++) {
			val = rtnl_route_get_metric(tmpl, i);
			if (val != UINT_MAX)
				NLA_PUT_U32(msg, i, val);
		}

		nla_nest_end(msg, metrics);
	}

#if 0
	RTA_IIF,
	RTA_MULTIPATH,
	RTA_PROTOINFO,
	RTA_FLOW,
	RTA_CACHEINFO,
	RTA_SESSION,
	RTA_MP_ALGO,
#endif

	return msg;

nla_put_failure:
	nlmsg_free(msg);
	return NULL;
}

struct nl_msg *rtnl_route_build_add_request(struct rtnl_route *tmpl, int flags)
{
	return build_route_msg(tmpl, RTM_NEWROUTE, NLM_F_CREATE | flags);
}

int rtnl_route_add(struct nl_handle *handle, struct rtnl_route *route,
		   int flags)
{
	struct nl_msg *msg;
	int err;

	msg = rtnl_route_build_add_request(route, flags);
	if (!msg)
		return nl_get_errno();

	err = nl_send_auto_complete(handle, msg);
	nlmsg_free(msg);
	if (err < 0)
		return err;

	return nl_wait_for_ack(handle);
}

struct nl_msg *rtnl_route_build_del_request(struct rtnl_route *tmpl, int flags)
{
	return build_route_msg(tmpl, RTM_DELROUTE, flags);
}

int rtnl_route_del(struct nl_handle *handle, struct rtnl_route *route,
		   int flags)
{
	struct nl_msg *msg;
	int err;

	msg = rtnl_route_build_del_request(route, flags);
	if (!msg)
		return nl_get_errno();

	err = nl_send_auto_complete(handle, msg);
	nlmsg_free(msg);
	if (err < 0)
		return err;

	return nl_wait_for_ack(handle);
}

/** @} */

static struct nl_af_group route_groups[] = {
	{ AF_INET,	RTNLGRP_IPV4_ROUTE },
	{ AF_INET6,	RTNLGRP_IPV6_ROUTE },
	{ AF_DECnet,	RTNLGRP_DECnet_ROUTE },
	{ END_OF_GROUP_LIST },
};

static struct nl_cache_ops rtnl_route_ops = {
	.co_name		= "route/route",
	.co_hdrsize		= sizeof(struct rtmsg),
	.co_msgtypes		= {
					{ RTM_NEWROUTE, NL_ACT_NEW, "new" },
					{ RTM_DELROUTE, NL_ACT_DEL, "del" },
					{ RTM_GETROUTE, NL_ACT_GET, "get" },
					END_OF_MSGTYPES_LIST,
				  },
	.co_protocol		= NETLINK_ROUTE,
	.co_groups		= route_groups,
	.co_request_update	= route_request_update,
	.co_msg_parser		= route_msg_parser,
	.co_obj_ops		= &route_obj_ops,
};

static void __init route_init(void)
{
	nl_cache_mngt_register(&rtnl_route_ops);
}

static void __exit route_exit(void)
{
	nl_cache_mngt_unregister(&rtnl_route_ops);
}
Пример #22
0
/**
 * virNetDevMacVLanDelete:
 *
 * @ifname: Name of the interface
 *
 * Tear down an interface with the given name.
 *
 * Returns 0 on success, -1 on fatal error.
 */
int virNetDevMacVLanDelete(const char *ifname)
{
    int rc = -1;
    struct nlmsghdr *resp;
    struct nlmsgerr *err;
    struct ifinfomsg ifinfo = { .ifi_family = AF_UNSPEC };
    unsigned char *recvbuf = NULL;
    unsigned int recvbuflen;
    struct nl_msg *nl_msg;

    nl_msg = nlmsg_alloc_simple(RTM_DELLINK,
                                NLM_F_REQUEST | NLM_F_CREATE | NLM_F_EXCL);
    if (!nl_msg) {
        virReportOOMError();
        return -1;
    }

    if (nlmsg_append(nl_msg,  &ifinfo, sizeof(ifinfo), NLMSG_ALIGNTO) < 0)
        goto buffer_too_small;

    if (nla_put(nl_msg, IFLA_IFNAME, strlen(ifname)+1, ifname) < 0)
        goto buffer_too_small;

    if (virNetlinkCommand(nl_msg, &recvbuf, &recvbuflen, 0) < 0) {
        goto cleanup;
    }

    if (recvbuflen < NLMSG_LENGTH(0) || recvbuf == NULL)
        goto malformed_resp;

    resp = (struct nlmsghdr *)recvbuf;

    switch (resp->nlmsg_type) {
    case NLMSG_ERROR:
        err = (struct nlmsgerr *)NLMSG_DATA(resp);
        if (resp->nlmsg_len < NLMSG_LENGTH(sizeof(*err)))
            goto malformed_resp;

        if (err->error) {
            virReportSystemError(-err->error,
                                 _("error destroying %s interface"),
                                 ifname);
            goto cleanup;
        }
        break;

    case NLMSG_DONE:
        break;

    default:
        goto malformed_resp;
    }

    rc = 0;
cleanup:
    nlmsg_free(nl_msg);
    VIR_FREE(recvbuf);
    return rc;

malformed_resp:
    virNetDevError(VIR_ERR_INTERNAL_ERROR, "%s",
                   _("malformed netlink response message"));
    goto cleanup;

buffer_too_small:
    virNetDevError(VIR_ERR_INTERNAL_ERROR, "%s",
                   _("allocated netlink buffer is too small"));
    goto cleanup;
}
Пример #23
0
static int build_rule_msg(struct rtnl_rule *tmpl, int cmd, int flags,
			  struct nl_msg **result)
{
	struct nl_msg *msg;
	struct fib_rule_hdr frh = {
		.family = tmpl->r_family,
		.table = tmpl->r_table,
		.action = tmpl->r_action,
		.flags = tmpl->r_flags,
		.tos = tmpl->r_dsfield,
	};

	if (!(tmpl->ce_mask & RULE_ATTR_FAMILY))
		return -NLE_MISSING_ATTR;

	msg = nlmsg_alloc_simple(cmd, flags);
	if (!msg)
		return -NLE_NOMEM;

	if (nlmsg_append(msg, &frh, sizeof(frh), NLMSG_ALIGNTO) < 0)
		goto nla_put_failure;

	if (tmpl->ce_mask & RULE_ATTR_SRC) {
		frh.src_len = nl_addr_get_prefixlen(tmpl->r_src);
		NLA_PUT_ADDR(msg, FRA_SRC, tmpl->r_src);
	}

	if (tmpl->ce_mask & RULE_ATTR_DST) {
		frh.dst_len = nl_addr_get_prefixlen(tmpl->r_dst);
		NLA_PUT_ADDR(msg, FRA_DST, tmpl->r_dst);
	}

	if (tmpl->ce_mask & RULE_ATTR_IIFNAME)
		NLA_PUT_STRING(msg, FRA_IIFNAME, tmpl->r_iifname);

	if (tmpl->ce_mask & RULE_ATTR_OIFNAME)
		NLA_PUT_STRING(msg, FRA_OIFNAME, tmpl->r_oifname);

	if (tmpl->ce_mask & RULE_ATTR_PRIO)
		NLA_PUT_U32(msg, FRA_PRIORITY, tmpl->r_prio);

	if (tmpl->ce_mask & RULE_ATTR_MARK)
		NLA_PUT_U32(msg, FRA_FWMARK, tmpl->r_mark);

	if (tmpl->ce_mask & RULE_ATTR_MASK)
		NLA_PUT_U32(msg, FRA_FWMASK, tmpl->r_mask);

	if (tmpl->ce_mask & RULE_ATTR_GOTO)
		NLA_PUT_U32(msg, FRA_GOTO, tmpl->r_goto);

	if (tmpl->ce_mask & RULE_ATTR_FLOW)
		NLA_PUT_U32(msg, FRA_FLOW, tmpl->r_flow);


	*result = msg;
	return 0;

nla_put_failure:
	nlmsg_free(msg);
	return -NLE_MSGSIZE;
}

/**
 * Build netlink request message to add a new rule
 * @arg tmpl		template with data of new rule
 * @arg flags		additional netlink message flags
 *
 * Builds a new netlink message requesting a addition of a new
 * rule. The netlink message header isn't fully equipped with
 * all relevant fields and must thus be sent out via nl_send_auto_complete()
 * or supplemented as needed. \a tmpl must contain the attributes of the new
 * address set via \c rtnl_rule_set_* functions.
 * 
 * @return The netlink message
 */
int rtnl_rule_build_add_request(struct rtnl_rule *tmpl, int flags,
				struct nl_msg **result)
{
	return build_rule_msg(tmpl, RTM_NEWRULE, NLM_F_CREATE | flags,
			      result);
}

/**
 * Add a new rule
 * @arg sk		Netlink socket.
 * @arg tmpl		template with requested changes
 * @arg flags		additional netlink message flags
 *
 * Builds a netlink message by calling rtnl_rule_build_add_request(),
 * sends the request to the kernel and waits for the next ACK to be
 * received and thus blocks until the request has been fullfilled.
 *
 * @return 0 on sucess or a negative error if an error occured.
 */
int rtnl_rule_add(struct nl_sock *sk, struct rtnl_rule *tmpl, int flags)
{
	struct nl_msg *msg;
	int err;
	
	if ((err = rtnl_rule_build_add_request(tmpl, flags, &msg)) < 0)
		return err;

	err = nl_send_auto_complete(sk, msg);
	nlmsg_free(msg);
	if (err < 0)
		return err;

	return wait_for_ack(sk);
}

/** @} */

/**
 * @name Rule Deletion
 * @{
 */

/**
 * Build a netlink request message to delete a rule
 * @arg rule		rule to delete
 * @arg flags		additional netlink message flags
 *
 * Builds a new netlink message requesting a deletion of a rule.
 * The netlink message header isn't fully equipped with all relevant
 * fields and must thus be sent out via nl_send_auto_complete()
 * or supplemented as needed. \a rule must point to an existing
 * address.
 *
 * @return The netlink message
 */
int rtnl_rule_build_delete_request(struct rtnl_rule *rule, int flags,
				   struct nl_msg **result)
{
	return build_rule_msg(rule, RTM_DELRULE, flags, result);
}

/**
 * Delete a rule
 * @arg sk		Netlink socket.
 * @arg rule		rule to delete
 * @arg flags		additional netlink message flags
 *
 * Builds a netlink message by calling rtnl_rule_build_delete_request(),
 * sends the request to the kernel and waits for the next ACK to be
 * received and thus blocks until the request has been fullfilled.
 *
 * @return 0 on sucess or a negative error if an error occured.
 */
int rtnl_rule_delete(struct nl_sock *sk, struct rtnl_rule *rule, int flags)
{
	struct nl_msg *msg;
	int err;
	
	if ((err = rtnl_rule_build_delete_request(rule, flags, &msg)) < 0)
		return err;

	err = nl_send_auto_complete(sk, msg);
	nlmsg_free(msg);
	if (err < 0)
		return err;

	return wait_for_ack(sk);
}

/** @} */

/**
 * @name Attribute Modification
 * @{
 */

void rtnl_rule_set_family(struct rtnl_rule *rule, int family)
{
	rule->r_family = family;
	rule->ce_mask |= RULE_ATTR_FAMILY;
}
Пример #24
0
TError TNlLink::AddXVlan(const std::string &vlantype,
                         const std::string &master,
                         uint32_t type,
                         const std::string &hw,
                         int mtu) {
    TError error = TError::Success();
    int ret;
    uint32_t masterIdx;
    struct nl_msg *msg;
    struct nlattr *linkinfo, *infodata;
    struct ifinfomsg ifi = { 0 };
    struct ether_addr *ea = nullptr;
    auto Name = GetName();

    if (hw.length()) {
        // FIXME THREADS
        ea = ether_aton(hw.c_str());
        if (!ea)
            return TError(EError::Unknown, "Invalid " + vlantype + " mac address " + hw);
    }

    TNlLink masterLink(Nl, master);
    error = masterLink.Load();
    if (error)
        return error;
    masterIdx = masterLink.GetIndex();

    msg = nlmsg_alloc_simple(RTM_NEWLINK, NLM_F_CREATE);
    if (!msg)
        return TError(EError::Unknown, "Unable to add " + vlantype + ": no memory");

    ret = nlmsg_append(msg, &ifi, sizeof(ifi), NLMSG_ALIGNTO);
    if (ret < 0) {
        error = TError(EError::Unknown, "Unable to add " + vlantype + ": " + nl_geterror(ret));
        goto free_msg;
    }

    /* link configuration */
    ret = nla_put(msg, IFLA_LINK, sizeof(uint32_t), &masterIdx);
    if (ret < 0) {
        error = TError(EError::Unknown, std::string("Unable to put IFLA_LINK: ") + nl_geterror(ret));
        goto free_msg;
    }
    ret = nla_put(msg, IFLA_IFNAME, Name.length() + 1, Name.c_str());
    if (ret < 0) {
        error = TError(EError::Unknown, std::string("Unable to put IFLA_IFNAME: ") + nl_geterror(ret));
        goto free_msg;
    }

    if (mtu > 0) {
        ret = nla_put(msg, IFLA_MTU, sizeof(int), &mtu);
        if (ret < 0) {
            error = TError(EError::Unknown, std::string("Unable to put IFLA_MTU: ") + nl_geterror(ret));
            goto free_msg;
        }
    }

    if (ea) {
        struct nl_addr *addr = nl_addr_build(AF_LLC, ea, ETH_ALEN);
        ret = nla_put(msg, IFLA_ADDRESS, nl_addr_get_len(addr), nl_addr_get_binary_addr(addr));
        if (ret < 0) {
            error = TError(EError::Unknown, std::string("Unable to put IFLA_ADDRESS: ") + nl_geterror(ret));
            goto free_msg;
        }
        nl_addr_put(addr);
    }

    /* link type */
    linkinfo = nla_nest_start(msg, IFLA_LINKINFO);
    if (!linkinfo) {
        error = TError(EError::Unknown, "Unable to add " + vlantype + ": can't nest IFLA_LINKINFO");
        goto free_msg;
    }
    ret = nla_put(msg, IFLA_INFO_KIND, vlantype.length() + 1, vlantype.c_str());
    if (ret < 0) {
        error = TError(EError::Unknown, std::string("Unable to put IFLA_INFO_KIND: ") + nl_geterror(ret));
        goto free_msg;
    }

    /* xvlan specific */
    infodata = nla_nest_start(msg, IFLA_INFO_DATA);
    if (!infodata) {
        error = TError(EError::Unknown, "Unable to add " + vlantype + ": can't nest IFLA_INFO_DATA");
        goto free_msg;
    }

    if (vlantype == "macvlan") {
        ret = nla_put(msg, IFLA_MACVLAN_MODE, sizeof(uint32_t), &type);
        if (ret < 0) {
            error = TError(EError::Unknown, std::string("Unable to put IFLA_MACVLAN_MODE: ") + nl_geterror(ret));
            goto free_msg;
        }
#ifdef IFLA_IPVLAN_MAX
    } else if (vlantype == "ipvlan") {
        uint16_t mode = type;
        ret = nla_put(msg, IFLA_IPVLAN_MODE, sizeof(uint16_t), &mode);
        if (ret < 0) {
            error = TError(EError::Unknown, std::string("Unable to put IFLA_IPVLAN_MODE: ") + nl_geterror(ret));
            goto free_msg;
        }
#endif
    }
    nla_nest_end(msg, infodata);
    nla_nest_end(msg, linkinfo);

    L() << "netlink: add " << vlantype << " " << Name << " master " << master
        << " type " << type << " hw " << hw << " mtu " << mtu << std::endl;

    ret = nl_send_sync(GetSock(), msg);
    if (ret)
        return Error(ret, "Cannot add " + vlantype);

    return Load();

free_msg:
    nlmsg_free(msg);
    return error;

}
Пример #25
0
int opal_btl_usnic_nl_ip_rt_lookup(struct usnic_rtnl_sk *unlsk,
                                   const char *src_ifname,
                                   uint32_t src_addr,
                                   uint32_t dst_addr, int *metric)
{
	struct nl_msg *nlm;
	struct rtmsg rmsg;
	struct nl_lookup_arg arg;
	int	msg_cnt;
	int err;
	int oif;

	oif = if_nametoindex(src_ifname);
	if (0 == oif) {
	    return errno;
	}

	arg.nh_addr 	= 0;
	arg.oif		= oif;
	arg.found	= 0;
	arg.replied	= 0;
	arg.unlsk	= unlsk;
	arg.msg_count = msg_cnt = 0;

	memset(&rmsg, 0, sizeof(rmsg));
	rmsg.rtm_family = AF_INET;
	rmsg.rtm_dst_len = sizeof(dst_addr)*8;
	rmsg.rtm_src_len = sizeof(src_addr)*8;

	nlm = nlmsg_alloc_simple(RTM_GETROUTE, 0);
	nlmsg_append(nlm, &rmsg, sizeof(rmsg), NLMSG_ALIGNTO);
	nla_put_u32(nlm, RTA_DST, dst_addr);
	nla_put_u32(nlm, RTA_SRC, src_addr);

	err = rtnl_send_ack_disable(unlsk, nlm);
	nlmsg_free(nlm);
	if (err < 0) {
		usnic_err("Failed to send nl route message to kernel, "
			"error %s\n", nl_geterror());
		return err;
	}

	err = nl_socket_modify_cb(unlsk->nlh, NL_CB_MSG_IN, NL_CB_CUSTOM,
					rtnl_raw_parse_cb, &arg);
	if (err != 0) {
		usnic_err("Failed to setup callback function, error %s\n", nl_geterror());
		return err;
	}

	while (!arg.replied) {
		err = nl_recvmsgs_default(unlsk->nlh);
		if (err < 0) {
			usnic_err("Failed to receive nl route message from "
				"kernel, error %s\n", nl_geterror());
			return err;
		}

		/*
		 * the return value of nl_recvmsgs_default does not tell
		 * whether it returns because of successful read or socket
		 * timeout. So we compare msg count before and after the call
		 * to decide if no new message arrives. In such case,
		 * this function needs to terminate to prevent the caller from
		 * blocking forever
		 * NL_CB_MSG_IN traps every received message, so
		 * there should be no premature exit
		 */
		if (msg_cnt != arg.msg_count)
			msg_cnt = arg.msg_count;
		else
			break;
	}

	if (arg.found) {
                if (metric != NULL) {
                    *metric = arg.metric;
                }
		return 0;
	}
	else {
		return -1;
	}
}
Пример #26
0
/**
 * Send netlink message.
 * @arg sk		Netlink socket.
 * @arg msg		Netlink message to be sent.
 * @arg iov		iovec to be sent.
 * @arg iovlen		number of struct iovec to be sent.
 * @see nl_sendmsg()
 * @return Number of characters sent on success or a negative error code.
 */
int nl_send_iovec(struct nl_sock *sk, struct nl_msg *msg, struct iovec *iov, unsigned iovlen)
{
	struct sockaddr_nl *dst;
	struct ucred *creds;
	struct msghdr hdr = {
		.msg_name = (void *) &sk->s_peer,
		.msg_namelen = sizeof(struct sockaddr_nl),
		.msg_iov = iov,
		.msg_iovlen = iovlen,
	};

	/* Overwrite destination if specified in the message itself, defaults
	 * to the peer address of the socket.
	 */
	dst = nlmsg_get_dst(msg);
	if (dst->nl_family == AF_NETLINK)
		hdr.msg_name = dst;

	/* Add credentials if present. */
	creds = nlmsg_get_creds(msg);
	if (creds != NULL) {
		char buf[CMSG_SPACE(sizeof(struct ucred))];
		struct cmsghdr *cmsg;

		hdr.msg_control = buf;
		hdr.msg_controllen = sizeof(buf);

		cmsg = CMSG_FIRSTHDR(&hdr);
		cmsg->cmsg_level = SOL_SOCKET;
		cmsg->cmsg_type = SCM_CREDENTIALS;
		cmsg->cmsg_len = CMSG_LEN(sizeof(struct ucred));
		memcpy(CMSG_DATA(cmsg), creds, sizeof(struct ucred));
	}

	return nl_sendmsg(sk, msg, &hdr);
}



/**
* Send netlink message.
* @arg sk		Netlink socket.
* @arg msg		Netlink message to be sent.
* @see nl_sendmsg()
* @return Number of characters sent on success or a negative error code.
*/
int nl_send(struct nl_sock *sk, struct nl_msg *msg)
{
	struct iovec iov = {
		.iov_base = (void *) nlmsg_hdr(msg),
		.iov_len = nlmsg_hdr(msg)->nlmsg_len,
	};

	return nl_send_iovec(sk, msg, &iov, 1);
}

void nl_auto_complete(struct nl_sock *sk, struct nl_msg *msg)
{
	struct nlmsghdr *nlh;

	nlh = nlmsg_hdr(msg);
	if (nlh->nlmsg_pid == 0)
		nlh->nlmsg_pid = sk->s_local.nl_pid;

	if (nlh->nlmsg_seq == 0)
		nlh->nlmsg_seq = sk->s_seq_next++;

	if (msg->nm_protocol == -1)
		msg->nm_protocol = sk->s_proto;

	nlh->nlmsg_flags |= NLM_F_REQUEST;

	if (!(sk->s_flags & NL_NO_AUTO_ACK))
		nlh->nlmsg_flags |= NLM_F_ACK;
}

/**
 * Send netlink message and check & extend header values as needed.
 * @arg sk		Netlink socket.
 * @arg msg		Netlink message to be sent.
 *
 * Checks the netlink message \c nlh for completness and extends it
 * as required before sending it out. Checked fields include pid,
 * sequence nr, and flags.
 *
 * @see nl_send()
 * @return Number of characters sent or a negative error code.
 */
int nl_send_auto_complete(struct nl_sock *sk, struct nl_msg *msg)
{
	struct nl_cb *cb = sk->s_cb;

	nl_auto_complete(sk, msg);

	if (cb->cb_send_ow)
		return cb->cb_send_ow(sk, msg);
	else
		return nl_send(sk, msg);
}

/**
 * Send simple netlink message using nl_send_auto_complete()
 * @arg sk		Netlink socket.
 * @arg type		Netlink message type.
 * @arg flags		Netlink message flags.
 * @arg buf		Data buffer.
 * @arg size		Size of data buffer.
 *
 * Builds a netlink message with the specified type and flags and
 * appends the specified data as payload to the message.
 *
 * @see nl_send_auto_complete()
 * @return Number of characters sent on success or a negative error code.
 */
int nl_send_simple(struct nl_sock *sk, int type, int flags, void *buf,
		   size_t size)
{
	int err;
	struct nl_msg *msg;

	msg = nlmsg_alloc_simple(type, flags);
	if (!msg)
		return -NLE_NOMEM;

	if (buf && size) {
		err = nlmsg_append(msg, buf, size, NLMSG_ALIGNTO);
		if (err < 0)
			goto errout;
	}
	

	err = nl_send_auto_complete(sk, msg);
errout:
	nlmsg_free(msg);

	return err;
}

/** @} */

/**
 * @name Receive
 * @{
 */

/**
 * Receive data from netlink socket
 * @arg sk		Netlink socket.
 * @arg nla		Destination pointer for peer's netlink address.
 * @arg buf		Destination pointer for message content.
 * @arg creds		Destination pointer for credentials.
 *
 * Receives a netlink message, allocates a buffer in \c *buf and
 * stores the message content. The peer's netlink address is stored
 * in \c *nla. The caller is responsible for freeing the buffer allocated
 * in \c *buf if a positive value is returned.  Interruped system calls
 * are handled by repeating the read. The input buffer size is determined
 * by peeking before the actual read is done.
 *
 * A non-blocking sockets causes the function to return immediately with
 * a return value of 0 if no data is available.
 *
 * @return Number of octets read, 0 on EOF or a negative error code.
 */
int nl_recv(struct nl_sock *sk, struct sockaddr_nl *nla,
	    unsigned char **buf, struct ucred **creds)
{
	int n;
	int flags = 0;
	static int page_size = 0;
	struct iovec iov;
	struct msghdr msg = {
		.msg_name = (void *) nla,
		.msg_namelen = sizeof(struct sockaddr_nl),
		.msg_iov = &iov,
		.msg_iovlen = 1,
		.msg_control = NULL,
		.msg_controllen = 0,
		.msg_flags = 0,
	};
	struct cmsghdr *cmsg;

	if (sk->s_flags & NL_MSG_PEEK)
		flags |= MSG_PEEK;

	if (page_size == 0)
		page_size = getpagesize();

	iov.iov_len = page_size;
	iov.iov_base = *buf = malloc(iov.iov_len);

	if (sk->s_flags & NL_SOCK_PASSCRED) {
		msg.msg_controllen = CMSG_SPACE(sizeof(struct ucred));
		msg.msg_control = calloc(1, msg.msg_controllen);
	}
retry:

	n = recvmsg(sk->s_fd, &msg, flags);
	if (!n)
		goto abort;
	else if (n < 0) {
		if (errno == EINTR) {
			NL_DBG(3, "recvmsg() returned EINTR, retrying\n");
			goto retry;
		} else if (errno == EAGAIN) {
			NL_DBG(3, "recvmsg() returned EAGAIN, aborting\n");
			goto abort;
		} else {
			free(msg.msg_control);
			free(*buf);
			return -nl_syserr2nlerr(errno);
		}
	}

	if (iov.iov_len < n ||
	    msg.msg_flags & MSG_TRUNC) {
		/* Provided buffer is not long enough, enlarge it
		 * and try again. */
		iov.iov_len *= 2;
		iov.iov_base = *buf = realloc(*buf, iov.iov_len);
		goto retry;
	} else if (msg.msg_flags & MSG_CTRUNC) {
		msg.msg_controllen *= 2;
		msg.msg_control = realloc(msg.msg_control, msg.msg_controllen);
		goto retry;
	} else if (flags != 0) {
		/* Buffer is big enough, do the actual reading */
		flags = 0;
		goto retry;
	}

	if (msg.msg_namelen != sizeof(struct sockaddr_nl)) {
		free(msg.msg_control);
		free(*buf);
		return -NLE_NOADDR;
	}

	for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
		if (cmsg->cmsg_level == SOL_SOCKET &&
		    cmsg->cmsg_type == SCM_CREDENTIALS) {
			*creds = calloc(1, sizeof(struct ucred));
			memcpy(*creds, CMSG_DATA(cmsg), sizeof(struct ucred));
			break;
		}
	}

	free(msg.msg_control);
	return n;

abort:
	free(msg.msg_control);
	free(*buf);
	return 0;
}

#define NL_CB_CALL(cb, type, msg) \
do { \
	err = nl_cb_call(cb, type, msg); \
	switch (err) { \
	case NL_OK: \
		err = 0; \
		break; \
	case NL_SKIP: \
		goto skip; \
	case NL_STOP: \
		goto stop; \
	default: \
		goto out; \
	} \
} while (0)

static int recvmsgs(struct nl_sock *sk, struct nl_cb *cb)
{
	int n, err = 0, multipart = 0;
	unsigned char *buf = NULL;
	struct nlmsghdr *hdr;
	struct sockaddr_nl nla = {0};
	struct nl_msg *msg = NULL;
	struct ucred *creds = NULL;

continue_reading:
	NL_DBG(3, "Attempting to read from %p\n", sk);
	if (cb->cb_recv_ow)
		n = cb->cb_recv_ow(sk, &nla, &buf, &creds);
	else
		n = nl_recv(sk, &nla, &buf, &creds);

	if (n <= 0)
		return n;

	NL_DBG(3, "recvmsgs(%p): Read %d bytes\n", sk, n);

	hdr = (struct nlmsghdr *) buf;
	while (nlmsg_ok(hdr, n)) {
		NL_DBG(3, "recgmsgs(%p): Processing valid message...\n", sk);

		nlmsg_free(msg);
		msg = nlmsg_convert(hdr);
		if (!msg) {
			err = -NLE_NOMEM;
			goto out;
		}

		nlmsg_set_proto(msg, sk->s_proto);
		nlmsg_set_src(msg, &nla);
		if (creds)
			nlmsg_set_creds(msg, creds);

		/* Raw callback is the first, it gives the most control
		 * to the user and he can do his very own parsing. */
		if (cb->cb_set[NL_CB_MSG_IN])
			NL_CB_CALL(cb, NL_CB_MSG_IN, msg);

		/* Sequence number checking. The check may be done by
		 * the user, otherwise a very simple check is applied
		 * enforcing strict ordering */
		if (cb->cb_set[NL_CB_SEQ_CHECK])
			NL_CB_CALL(cb, NL_CB_SEQ_CHECK, msg);
		else if (hdr->nlmsg_seq != sk->s_seq_expect) {
			if (cb->cb_set[NL_CB_INVALID])
				NL_CB_CALL(cb, NL_CB_INVALID, msg);
			else {
				err = -NLE_SEQ_MISMATCH;
				goto out;
			}
		}

		if (hdr->nlmsg_type == NLMSG_DONE ||
		    hdr->nlmsg_type == NLMSG_ERROR ||
		    hdr->nlmsg_type == NLMSG_NOOP ||
		    hdr->nlmsg_type == NLMSG_OVERRUN) {
			/* We can't check for !NLM_F_MULTI since some netlink
			 * users in the kernel are broken. */
			sk->s_seq_expect++;
			NL_DBG(3, "recvmsgs(%p): Increased expected " \
			       "sequence number to %d\n",
			       sk, sk->s_seq_expect);
		}

		if (hdr->nlmsg_flags & NLM_F_MULTI)
			multipart = 1;
	
		/* Other side wishes to see an ack for this message */
		if (hdr->nlmsg_flags & NLM_F_ACK) {
			if (cb->cb_set[NL_CB_SEND_ACK])
				NL_CB_CALL(cb, NL_CB_SEND_ACK, msg);
			else {
				/* FIXME: implement */
			}
		}

		/* messages terminates a multpart message, this is
		 * usually the end of a message and therefore we slip
		 * out of the loop by default. the user may overrule
		 * this action by skipping this packet. */
		if (hdr->nlmsg_type == NLMSG_DONE) {
			multipart = 0;
			if (cb->cb_set[NL_CB_FINISH])
				NL_CB_CALL(cb, NL_CB_FINISH, msg);
		}

		/* Message to be ignored, the default action is to
		 * skip this message if no callback is specified. The
		 * user may overrule this action by returning
		 * NL_PROCEED. */
		else if (hdr->nlmsg_type == NLMSG_NOOP) {
			if (cb->cb_set[NL_CB_SKIPPED])
				NL_CB_CALL(cb, NL_CB_SKIPPED, msg);
			else
				goto skip;
		}

		/* Data got lost, report back to user. The default action is to
		 * quit parsing. The user may overrule this action by retuning
		 * NL_SKIP or NL_PROCEED (dangerous) */
		else if (hdr->nlmsg_type == NLMSG_OVERRUN) {
			if (cb->cb_set[NL_CB_OVERRUN])
				NL_CB_CALL(cb, NL_CB_OVERRUN, msg);
			else {
				err = -NLE_MSG_OVERFLOW;
				goto out;
			}
		}

		/* Message carries a nlmsgerr */
		else if (hdr->nlmsg_type == NLMSG_ERROR) {
			struct nlmsgerr *e = nlmsg_data(hdr);

			if (hdr->nlmsg_len < nlmsg_msg_size(sizeof(*e))) {
				/* Truncated error message, the default action
				 * is to stop parsing. The user may overrule
				 * this action by returning NL_SKIP or
				 * NL_PROCEED (dangerous) */
				if (cb->cb_set[NL_CB_INVALID])
					NL_CB_CALL(cb, NL_CB_INVALID, msg);
				else {
					err = -NLE_MSG_TRUNC;
					goto out;
				}
			} else if (e->error) {
				/* Error message reported back from kernel. */
				if (cb->cb_err) {
					err = cb->cb_err(&nla, e,
							   cb->cb_err_arg);
					if (err < 0)
						goto out;
					else if (err == NL_SKIP)
						goto skip;
					else if (err == NL_STOP) {
						err = -nl_syserr2nlerr(e->error);
						goto out;
					}
				} else {
					err = -nl_syserr2nlerr(e->error);
					goto out;
				}
			} else if (cb->cb_set[NL_CB_ACK])
				NL_CB_CALL(cb, NL_CB_ACK, msg);
		} else {
			/* Valid message (not checking for MULTIPART bit to
			 * get along with broken kernels. NL_SKIP has no
			 * effect on this.  */
			if (cb->cb_set[NL_CB_VALID])
				NL_CB_CALL(cb, NL_CB_VALID, msg);
		}
skip:
		err = 0;
		hdr = nlmsg_next(hdr, &n);
	}
	
	nlmsg_free(msg);
	free(buf);
	free(creds);
	buf = NULL;
	msg = NULL;
	creds = NULL;

	if (multipart) {
		/* Multipart message not yet complete, continue reading */
		goto continue_reading;
	}
stop:
	err = 0;
out:
	nlmsg_free(msg);
	free(buf);
	free(creds);

	return err;
}
Пример #27
0
static int fill_ematch_sequence(struct nl_msg *msg, struct nl_list_head *list)
{
	struct rtnl_ematch *e;

	nl_list_for_each_entry(e, list, e_list) {
		struct tcf_ematch_hdr match = {
			.matchid = e->e_id,
			.kind = e->e_kind,
			.flags = e->e_flags,
		};
		struct nlattr *attr;
		int err = 0;

		if (!(attr = nla_nest_start(msg, e->e_index + 1)))
			return -NLE_NOMEM;

		if (nlmsg_append(msg, &match, sizeof(match), 0) < 0)
			return -NLE_NOMEM;

		if (e->e_ops->eo_fill)
			err = e->e_ops->eo_fill(e, msg);
		else if (e->e_flags & TCF_EM_SIMPLE)
			err = nlmsg_append(msg, e->e_data, 4, 0);
		else if (e->e_datalen > 0)
			err = nlmsg_append(msg, e->e_data, e->e_datalen, 0);

		NL_DBG(3, "msg %p: added ematch [%d] id=%d kind=%d flags=%d\n",
			  msg, e->e_index, match.matchid, match.kind, match.flags);

		if (err < 0)
			return -NLE_NOMEM;

		nla_nest_end(msg, attr);
	}

	nl_list_for_each_entry(e, list, e_list) {
		if (e->e_kind == TCF_EM_CONTAINER &&
		    fill_ematch_sequence(msg, &e->e_childs) < 0)
			return -NLE_NOMEM;
	}

	return 0;
}

int rtnl_ematch_fill_attr(struct nl_msg *msg, int attrid,
			  struct rtnl_ematch_tree *tree)
{
	struct tcf_ematch_tree_hdr thdr = {
		.progid = tree->et_progid,
	};
	struct nlattr *list, *topattr;
	int err, index = 0;

	/* Assign index number to each ematch to allow for references
	 * to be made while constructing the sequence of matches. */
	err = update_container_index(&tree->et_list, &index);
	if (err < 0)
		return err;

	if (!(topattr = nla_nest_start(msg, attrid)))
		goto nla_put_failure;

	thdr.nmatches = index;
	NLA_PUT(msg, TCA_EMATCH_TREE_HDR, sizeof(thdr), &thdr);

	if (!(list = nla_nest_start(msg, TCA_EMATCH_TREE_LIST)))
		goto nla_put_failure;

	if (fill_ematch_sequence(msg, &tree->et_list) < 0)
		goto nla_put_failure;

	nla_nest_end(msg, list);

	nla_nest_end(msg, topattr);

	return 0;

nla_put_failure:
	return -NLE_NOMEM;
}

/** @} */

extern int ematch_parse(void *, char **, struct nl_list_head *);

int rtnl_ematch_parse_expr(const char *expr, char **errp,
			   struct rtnl_ematch_tree **result)
{
	struct rtnl_ematch_tree *tree;
	YY_BUFFER_STATE buf = NULL;
	yyscan_t scanner = NULL;
	int err;

	NL_DBG(2, "Parsing ematch expression \"%s\"\n", expr);

	if (!(tree = rtnl_ematch_tree_alloc(RTNL_EMATCH_PROGID)))
		return -NLE_FAILURE;

	if ((err = ematch_lex_init(&scanner)) < 0) {
		err = -NLE_FAILURE;
		goto errout;
	}

	buf = ematch__scan_string(expr, scanner);

	if ((err = ematch_parse(scanner, errp, &tree->et_list)) != 0) {
		ematch__delete_buffer(buf, scanner);
		err = -NLE_PARSE_ERR;
		goto errout;
	}

	ematch_lex_destroy(scanner);
	*result = tree;

	return 0;

errout:
	if (scanner)
		ematch_lex_destroy(scanner);

	rtnl_ematch_tree_free(tree);

	return err;
}

static const char *layer_txt[] = {
	[TCF_LAYER_LINK]	= "eth",
	[TCF_LAYER_NETWORK]	= "ip",
	[TCF_LAYER_TRANSPORT]	= "tcp",
};

char *rtnl_ematch_offset2txt(uint8_t layer, uint16_t offset, char *buf, size_t len)
{
	snprintf(buf, len, "%s+%u",
		 (layer <= TCF_LAYER_MAX) ? layer_txt[layer] : "?",
		 offset);

	return buf;
}

static const char *operand_txt[] = {
	[TCF_EM_OPND_EQ] = "=",
	[TCF_EM_OPND_LT] = "<",
	[TCF_EM_OPND_GT] = ">",
};

char *rtnl_ematch_opnd2txt(uint8_t opnd, char *buf, size_t len)
{
	snprintf(buf, len, "%s",
		opnd < ARRAY_SIZE(operand_txt) ? operand_txt[opnd] : "?");

	return buf;
}
Пример #28
0
int main(int argc, char *argv[])
{
	struct nl_handle *nlh;
	struct nl_cache *link_cache, *route_cache;
	struct nl_addr *dst;
	struct rtnl_route *route;
        struct ip_lookup_res res;
	struct nl_dump_params params = {
		.dp_fd = stdout,
		.dp_type = NL_DUMP_FULL
	};
	int err = 1;

	if (argc < 2 || !strcmp(argv[1], "-h"))
		print_usage();

	if (nltool_init(argc, argv) < 0)
		goto errout;

	nlh = nltool_alloc_handle();
	if (!nlh)
		goto errout;

	route = rtnl_route_alloc();
	if (!route)
		goto errout_free_handle;

	if (nltool_connect(nlh, NETLINK_ROUTE) < 0)
		goto errout_free_route;

	link_cache = nltool_alloc_link_cache(nlh);
	if (!link_cache)
		goto errout_close;

	dst = nltool_addr_parse(argv[1]);
	if (!dst)
		goto errout_link_cache;

	route_cache = nltool_alloc_route_cache(nlh);
	if (!route_cache)
		goto errout_addr_put;

	{
		struct nl_msg *m;
		struct rtmsg rmsg = {
			.rtm_family = nl_addr_get_family(dst),
			.rtm_dst_len = nl_addr_get_prefixlen(dst),
		};

		m = nlmsg_alloc_simple(RTM_GETROUTE, 0);
		nlmsg_append(m, &rmsg, sizeof(rmsg), NLMSG_ALIGNTO);
		nla_put_addr(m, RTA_DST, dst);

		if ((err = nl_send_auto_complete(nlh, m)) < 0) {
			nlmsg_free(m);
			fprintf(stderr, "%s\n", nl_geterror());
			goto errout_route_cache;
		}

		nlmsg_free(m);

		nl_socket_modify_cb(nlh, NL_CB_VALID, NL_CB_CUSTOM, cb,
				 route_cache);

		if (nl_recvmsgs_default(nlh) < 0) {
			fprintf(stderr, "%s\n", nl_geterror());
			goto errout_route_cache;
		}
	}

        rtnl_route_set_dst(route, dst);
	nl_cache_dump_filter(route_cache, &params, (struct nl_object *) route);
        memset(&res, 0, sizeof(res));
        nl_cache_foreach_filter(route_cache, (struct nl_object *) route, route_proc_cb,
                                &res);

        printf("ip lookup result: oif idx: %d oif name %s ",
                res.oif, res.oifname);
        if (res.nh_addr) {
                char buf[INET_ADDRSTRLEN];
                inet_ntop(AF_INET, &res.nh_addr, buf, sizeof(buf));
                printf("via %s", buf);
        }
        printf ("\n");

	err = 0;
errout_route_cache:
	nl_cache_free(route_cache);
errout_addr_put:
	nl_addr_put(dst);
errout_link_cache:
	nl_cache_free(link_cache);
errout_close:
	nl_close(nlh);
errout_free_route:
        rtnl_route_put(route);
errout_free_handle:
	nl_handle_destroy(nlh);
errout:
	return err;
}
Пример #29
0
/**
 * virNetDevMacVLanCreate:
 *
 * @ifname: The name the interface is supposed to have; optional parameter
 * @type: The type of device, i.e., "macvtap", "macvlan"
 * @macaddress: The MAC address of the device
 * @srcdev: The name of the 'link' device
 * @macvlan_mode: The macvlan mode to use
 * @retry: Pointer to integer that will be '1' upon return if an interface
 *         with the same name already exists and it is worth to try
 *         again with a different name
 *
 * Create a macvtap device with the given properties.
 *
 * Returns 0 on success, -1 on fatal error.
 */
int
virNetDevMacVLanCreate(const char *ifname,
                       const char *type,
                       const unsigned char *macaddress,
                       const char *srcdev,
                       uint32_t macvlan_mode,
                       int *retry)
{
    int rc = -1;
    struct nlmsghdr *resp;
    struct nlmsgerr *err;
    struct ifinfomsg ifinfo = { .ifi_family = AF_UNSPEC };
    int ifindex;
    unsigned char *recvbuf = NULL;
    unsigned int recvbuflen;
    struct nl_msg *nl_msg;
    struct nlattr *linkinfo, *info_data;

    if (virNetDevGetIndex(srcdev, &ifindex) < 0)
        return -1;

    *retry = 0;

    nl_msg = nlmsg_alloc_simple(RTM_NEWLINK,
                                NLM_F_REQUEST | NLM_F_CREATE | NLM_F_EXCL);
    if (!nl_msg) {
        virReportOOMError();
        return -1;
    }

    if (nlmsg_append(nl_msg,  &ifinfo, sizeof(ifinfo), NLMSG_ALIGNTO) < 0)
        goto buffer_too_small;

    if (nla_put_u32(nl_msg, IFLA_LINK, ifindex) < 0)
        goto buffer_too_small;

    if (nla_put(nl_msg, IFLA_ADDRESS, VIR_MAC_BUFLEN, macaddress) < 0)
        goto buffer_too_small;

    if (ifname &&
        nla_put(nl_msg, IFLA_IFNAME, strlen(ifname)+1, ifname) < 0)
        goto buffer_too_small;

    if (!(linkinfo = nla_nest_start(nl_msg, IFLA_LINKINFO)))
        goto buffer_too_small;

    if (nla_put(nl_msg, IFLA_INFO_KIND, strlen(type), type) < 0)
        goto buffer_too_small;

    if (macvlan_mode > 0) {
        if (!(info_data = nla_nest_start(nl_msg, IFLA_INFO_DATA)))
            goto buffer_too_small;

        if (nla_put(nl_msg, IFLA_MACVLAN_MODE, sizeof(macvlan_mode),
                    &macvlan_mode) < 0)
            goto buffer_too_small;

        nla_nest_end(nl_msg, info_data);
    }

    nla_nest_end(nl_msg, linkinfo);

    if (virNetlinkCommand(nl_msg, &recvbuf, &recvbuflen, 0) < 0) {
        goto cleanup;
    }

    if (recvbuflen < NLMSG_LENGTH(0) || recvbuf == NULL)
        goto malformed_resp;

    resp = (struct nlmsghdr *)recvbuf;

    switch (resp->nlmsg_type) {
    case NLMSG_ERROR:
        err = (struct nlmsgerr *)NLMSG_DATA(resp);
        if (resp->nlmsg_len < NLMSG_LENGTH(sizeof(*err)))
            goto malformed_resp;

        switch (err->error) {

        case 0:
            break;

        case -EEXIST:
            *retry = 1;
            goto cleanup;

        default:
            virReportSystemError(-err->error,
                                 _("error creating %s type of interface"),
                                 type);
            goto cleanup;
        }
        break;

    case NLMSG_DONE:
        break;

    default:
        goto malformed_resp;
    }

    rc = 0;
cleanup:
    nlmsg_free(nl_msg);
    VIR_FREE(recvbuf);
    return rc;

malformed_resp:
    virNetDevError(VIR_ERR_INTERNAL_ERROR, "%s",
                   _("malformed netlink response message"));
    goto cleanup;

buffer_too_small:
    virNetDevError(VIR_ERR_INTERNAL_ERROR, "%s",
                   _("allocated netlink buffer is too small"));
    goto cleanup;
}
Пример #30
0
/**
 * Send netlink message with control over sendmsg() message header.
 * @arg handle		Netlink handle.
 * @arg msg		Netlink message to be sent.
 * @arg hdr		Sendmsg() message header.
 * @return Number of characters sent on sucess or a negative error code.
 */
int nl_sendmsg(struct nl_handle *handle, struct nl_msg *msg, struct msghdr *hdr)
{
	struct nl_cb *cb;
	int ret;

	struct iovec iov = {
		.iov_base = (void *) nlmsg_hdr(msg),
		.iov_len = nlmsg_hdr(msg)->nlmsg_len,
	};

	hdr->msg_iov = &iov;
	hdr->msg_iovlen = 1;

	nlmsg_set_src(msg, &handle->h_local);

	cb = nl_handle_get_cb(handle);
	if (cb->cb_set[NL_CB_MSG_OUT])
		if (nl_cb_call(cb, NL_CB_MSG_OUT, msg) != NL_PROCEED)
			return 0;

	ret = sendmsg(handle->h_fd, hdr, 0);
	if (ret < 0)
		return nl_errno(errno);

	return ret;
}


/**
 * Send netlink message.
 * @arg handle		Netlink handle
 * @arg msg		Netlink message to be sent.
 * @see nl_sendmsg()
 * @return Number of characters sent on success or a negative error code.
 */
int nl_send(struct nl_handle *handle, struct nl_msg *msg)
{
	struct sockaddr_nl *dst;
	struct ucred *creds;
	
	struct msghdr hdr = {
		.msg_name = (void *) &handle->h_peer,
		.msg_namelen = sizeof(struct sockaddr_nl),
	};

	/* Overwrite destination if specified in the message itself, defaults
	 * to the peer address of the handle.
	 */
	dst = nlmsg_get_dst(msg);
	if (dst->nl_family == AF_NETLINK)
		hdr.msg_name = dst;

	/* Add credentials if present. */
	creds = nlmsg_get_creds(msg);
	if (creds != NULL) {
		char buf[CMSG_SPACE(sizeof(struct ucred))];
		struct cmsghdr *cmsg;

		hdr.msg_control = buf;
		hdr.msg_controllen = sizeof(buf);

		cmsg = CMSG_FIRSTHDR(&hdr);
		cmsg->cmsg_level = SOL_SOCKET;
		cmsg->cmsg_type = SCM_CREDENTIALS;
		cmsg->cmsg_len = CMSG_LEN(sizeof(struct ucred));
		memcpy(CMSG_DATA(cmsg), creds, sizeof(struct ucred));
	}

	return nl_sendmsg(handle, msg, &hdr);
}

/**
 * Send netlink message and check & extend header values as needed.
 * @arg handle		Netlink handle.
 * @arg msg		Netlink message to be sent.
 *
 * Checks the netlink message \c nlh for completness and extends it
 * as required before sending it out. Checked fields include pid,
 * sequence nr, and flags.
 *
 * @see nl_send()
 * @return Number of characters sent or a negative error code.
 */
int nl_send_auto_complete(struct nl_handle *handle, struct nl_msg *msg)
{
	struct nlmsghdr *nlh;

	nlh = nlmsg_hdr(msg);
	if (nlh->nlmsg_pid == 0)
		nlh->nlmsg_pid = handle->h_local.nl_pid;

	if (nlh->nlmsg_seq == 0)
		nlh->nlmsg_seq = handle->h_seq_next++;
	
	nlh->nlmsg_flags |= (NLM_F_REQUEST | NLM_F_ACK);

	if (handle->h_cb->cb_send_ow)
		return handle->h_cb->cb_send_ow(handle, msg);
	else
		return nl_send(handle, msg);
}

/**
 * Send simple netlink message using nl_send_auto_complete()
 * @arg handle		Netlink handle.
 * @arg type		Netlink message type.
 * @arg flags		Netlink message flags.
 * @arg buf		Data buffer.
 * @arg size		Size of data buffer.
 *
 * Builds a netlink message with the specified type and flags and
 * appends the specified data as payload to the message.
 *
 * @see nl_send_auto_complete()
 * @return Number of characters sent on success or a negative error code.
 */
int nl_send_simple(struct nl_handle *handle, int type, int flags, void *buf,
		   size_t size)
{
	int err;
	struct nl_msg *msg;
	struct nlmsghdr nlh = {
		.nlmsg_len = nlmsg_msg_size(0),
		.nlmsg_type = type,
		.nlmsg_flags = flags,
	};

	msg = nlmsg_build(&nlh);
	if (!msg)
		return nl_errno(ENOMEM);

	if (buf && size)
		nlmsg_append(msg, buf, size, 1);

	err = nl_send_auto_complete(handle, msg);
	nlmsg_free(msg);

	return err;
}

/** @} */

/**
 * @name Receive
 * @{
 */

/**
 * Receive netlink message from netlink socket.
 * @arg handle		Netlink handle.
 * @arg nla		Destination pointer for peer's netlink address.
 * @arg buf		Destination pointer for message content.
 * @arg creds		Destination pointer for credentials.
 *
 * Receives a netlink message, allocates a buffer in \c *buf and
 * stores the message content. The peer's netlink address is stored
 * in \c *nla. The caller is responsible for freeing the buffer allocated
 * in \c *buf if a positive value is returned.  Interruped system calls
 * are handled by repeating the read. The input buffer size is determined
 * by peeking before the actual read is done.
 *
 * A non-blocking sockets causes the function to return immediately if
 * no data is available.
 *
 * @return Number of octets read, 0 on EOF or a negative error code.
 */
int nl_recv(struct nl_handle *handle, struct sockaddr_nl *nla,
	    unsigned char **buf, struct ucred **creds)
{
	int n;
	int flags = MSG_PEEK;

	struct iovec iov = {
		.iov_len = 4096,
	};

	struct msghdr msg = {
		.msg_name = (void *) nla,
		.msg_namelen = sizeof(sizeof(struct sockaddr_nl)),
		.msg_iov = &iov,
		.msg_iovlen = 1,
		.msg_control = NULL,
		.msg_controllen = 0,
		.msg_flags = 0,
	};
	struct cmsghdr *cmsg;

	iov.iov_base = *buf = calloc(1, iov.iov_len);

	if (handle->h_flags & NL_SOCK_PASSCRED) {
		msg.msg_controllen = CMSG_SPACE(sizeof(struct ucred));
		msg.msg_control = calloc(1, msg.msg_controllen);
	}
retry:

	if ((n = recvmsg(handle->h_fd, &msg, flags)) <= 0) {
		if (!n)
			goto abort;
		else if (n < 0) {
			if (errno == EINTR)
				goto retry;
			else if (errno == EAGAIN)
				goto abort;
			else {
				free(msg.msg_control);
				free(*buf);
				return nl_error(errno, "recvmsg failed");
			}
		}
	}
	
	if (iov.iov_len < n) {
		/* Provided buffer is not long enough, enlarge it
		 * and try again. */
		iov.iov_len *= 2;
		iov.iov_base = *buf = realloc(*buf, iov.iov_len);
		goto retry;
	} else if (msg.msg_flags & MSG_CTRUNC) {
		msg.msg_controllen *= 2;
		msg.msg_control = realloc(msg.msg_control, msg.msg_controllen);
		goto retry;
	} else if (flags != 0) {
		/* Buffer is big enough, do the actual reading */
		flags = 0;
		goto retry;
	}

	if (msg.msg_namelen != sizeof(struct sockaddr_nl)) {
		free(msg.msg_control);
		free(*buf);
		return nl_error(EADDRNOTAVAIL, "socket address size mismatch");
	}

	for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
		if (cmsg->cmsg_level == SOL_SOCKET &&
		    cmsg->cmsg_type == SCM_CREDENTIALS) {
			*creds = calloc(1, sizeof(struct ucred));
			memcpy(*creds, CMSG_DATA(cmsg), sizeof(struct ucred));
			break;
		}
	}

	free(msg.msg_control);
	return n;

abort:
	free(msg.msg_control);
	free(*buf);
	return 0;
}


/**
 * Receive a set of messages from a netlink socket.
 * @arg handle		netlink handle
 * @arg cb		set of callbacks to control the behaviour.
 *
 * Repeatedly calls nl_recv() and parses the messages as netlink
 * messages. Stops reading if one of the callbacks returns
 * NL_EXIT or nl_recv returns either 0 or a negative error code.
 *
 * A non-blocking sockets causes the function to return immediately if
 * no data is available.
 *
 * @return 0 on success or a negative error code from nl_recv().
 */
int nl_recvmsgs(struct nl_handle *handle, struct nl_cb *cb)
{
	int n, err = 0;
	unsigned char *buf = NULL;
	struct nlmsghdr *hdr;
	struct sockaddr_nl nla = {0};
	struct nl_msg *msg = NULL;
	struct ucred *creds = NULL;

continue_reading:
	if (cb->cb_recv_ow)
		n = cb->cb_recv_ow(handle, &nla, &buf, &creds);
	else
		n = nl_recv(handle, &nla, &buf, &creds);

	if (n <= 0)
		return n;

	NL_DBG(3, "recvmsgs(%p): Read %d bytes\n", handle, n);

	hdr = (struct nlmsghdr *) buf;
	while (nlmsg_ok(hdr, n)) {
		NL_DBG(3, "recgmsgs(%p): Processing valid message...\n",
		       handle);

		nlmsg_free(msg);
		msg = nlmsg_convert(hdr);
		if (!msg) {
			err = nl_errno(ENOMEM);
			goto out;
		}

		nlmsg_set_proto(msg, handle->h_proto);
		nlmsg_set_src(msg, &nla);
		if (creds)
			nlmsg_set_creds(msg, creds);

		/* Raw callback is the first, it gives the most control
		 * to the user and he can do his very own parsing. */
		if (cb->cb_set[NL_CB_MSG_IN]) {
			err = nl_cb_call(cb, NL_CB_MSG_IN, msg);
			if (err == NL_SKIP)
				goto skip;
			else if (err == NL_EXIT || err < 0)
				goto out;
		}

		/* Sequence number checking. The check may be done by
		 * the user, otherwise a very simple check is applied
		 * enforcing strict ordering */
		if (cb->cb_set[NL_CB_SEQ_CHECK]) {
			err = nl_cb_call(cb, NL_CB_SEQ_CHECK, msg);
			if (err == NL_SKIP)
				goto skip;
			else if (err == NL_EXIT || err < 0)
				goto out;
		} else if (hdr->nlmsg_seq != handle->h_seq_expect) {
			if (cb->cb_set[NL_CB_INVALID]) {
				err = nl_cb_call(cb, NL_CB_INVALID, msg);
				if (err == NL_SKIP)
					goto skip;
				else if (err == NL_EXIT || err < 0)
					goto out;
			} else
				goto out;
		}

		if (hdr->nlmsg_type == NLMSG_DONE ||
		    hdr->nlmsg_type == NLMSG_ERROR ||
		    hdr->nlmsg_type == NLMSG_NOOP ||
		    hdr->nlmsg_type == NLMSG_OVERRUN) {
			/* We can't check for !NLM_F_MULTI since some netlink
			 * users in the kernel are broken. */
			handle->h_seq_expect++;
			NL_DBG(3, "recvmsgs(%p): Increased expected " \
			       "sequence number to %d\n",
			       handle, handle->h_seq_expect);
		}
	
		/* Other side wishes to see an ack for this message */
		if (hdr->nlmsg_flags & NLM_F_ACK) {
			if (cb->cb_set[NL_CB_SEND_ACK]) {
				err = nl_cb_call(cb, NL_CB_SEND_ACK, msg);
				if (err == NL_SKIP)
					goto skip;
				else if (err == NL_EXIT || err < 0)
					goto out;
			} else {
				/* FIXME: implement */
			}
		}

		/* messages terminates a multpart message, this is
		 * usually the end of a message and therefore we slip
		 * out of the loop by default. the user may overrule
		 * this action by skipping this packet. */
		if (hdr->nlmsg_type == NLMSG_DONE) {
			if (cb->cb_set[NL_CB_FINISH]) {
				err = nl_cb_call(cb, NL_CB_FINISH, msg);
				if (err == NL_SKIP)
					goto skip;
				else if (err == NL_EXIT || err < 0)
					goto out;
			}
			err = 0;
			goto out;
		}

		/* Message to be ignored, the default action is to
		 * skip this message if no callback is specified. The
		 * user may overrule this action by returning
		 * NL_PROCEED. */
		else if (hdr->nlmsg_type == NLMSG_NOOP) {
			if (cb->cb_set[NL_CB_SKIPPED]) {
				err = nl_cb_call(cb, NL_CB_SKIPPED, msg);
				if (err == NL_SKIP)
					goto skip;
				else if (err == NL_EXIT || err < 0)
					goto out;
			} else
				goto skip;
		}

		/* Data got lost, report back to user. The default action is to
		 * quit parsing. The user may overrule this action by retuning
		 * NL_SKIP or NL_PROCEED (dangerous) */
		else if (hdr->nlmsg_type == NLMSG_OVERRUN) {
			if (cb->cb_set[NL_CB_OVERRUN]) {
				err = nl_cb_call(cb, NL_CB_OVERRUN, msg);
				if (err == NL_SKIP)
					goto skip;
				else if (err == NL_EXIT || err < 0)
					goto out;
			} else
				goto out;
		}

		/* Message carries a nlmsgerr */
		else if (hdr->nlmsg_type == NLMSG_ERROR) {
			struct nlmsgerr *e = nlmsg_data(hdr);

			if (hdr->nlmsg_len < nlmsg_msg_size(sizeof(*e))) {
				/* Truncated error message, the default action
				 * is to stop parsing. The user may overrule
				 * this action by returning NL_SKIP or
				 * NL_PROCEED (dangerous) */
				if (cb->cb_set[NL_CB_INVALID]) {
					err = nl_cb_call(cb, NL_CB_INVALID,
							 msg);
					if (err == NL_SKIP)
						goto skip;
					else if (err == NL_EXIT || err < 0)
						goto out;
				} else
					goto out;
			} else if (e->error) {
				/* Error message reported back from kernel. */
				if (cb->cb_err) {
					err = cb->cb_err(&nla, e,
							   cb->cb_err_arg);
					if (err == NL_SKIP)
						goto skip;
					else if (err == NL_EXIT || err < 0) {
						nl_error(-e->error,
							 "Netlink Error");
						err = e->error;
						goto out;
					}
				} else {
					nl_error(-e->error, "Netlink Error");
					err = e->error;
					goto out;
				}
			} else if (cb->cb_set[NL_CB_ACK]) {
				/* ACK */
				err = nl_cb_call(cb, NL_CB_ACK, msg);
				if (err == NL_SKIP)
					goto skip;
				else if (err == NL_EXIT || err < 0)
					goto out;
			}
		} else {
			/* Valid message (not checking for MULTIPART bit to
			 * get along with broken kernels. NL_SKIP has no
			 * effect on this.  */
			if (cb->cb_set[NL_CB_VALID]) {
				err = nl_cb_call(cb, NL_CB_VALID, msg);
				if (err == NL_SKIP)
					goto skip;
				else if (err == NL_EXIT || err < 0)
					goto out;
			}
		}
skip:
		hdr = nlmsg_next(hdr, &n);
	}
	
	nlmsg_free(msg);
	free(buf);
	free(creds);
	buf = NULL;
	msg = NULL;
	creds = NULL;

	/* Multipart message not yet complete, continue reading */
	goto continue_reading;

out:
	nlmsg_free(msg);
	free(buf);
	free(creds);

	return err;
}

/**
 * Receive a set of message from a netlink socket using handlers in nl_handle.
 * @arg handle		netlink handle
 *
 * Calls nl_recvmsgs() with the handlers configured in the netlink handle.
 */
int nl_recvmsgs_def(struct nl_handle *handle)
{
	if (handle->h_cb->cb_recvmsgs_ow)
		return handle->h_cb->cb_recvmsgs_ow(handle, handle->h_cb);
	else
		return nl_recvmsgs(handle, handle->h_cb);
}

static int ack_wait_handler(struct nl_msg *msg, void *arg)
{
	return NL_EXIT;
}

/**
 * Wait for ACK.
 * @arg handle		netlink handle
 * @pre The netlink socket must be in blocking state.
 *
 * Waits until an ACK is received for the latest not yet acknowledged
 * netlink message.
 */
int nl_wait_for_ack(struct nl_handle *handle)
{
	int err;
	struct nl_cb *cb = nl_cb_clone(nl_handle_get_cb(handle));

	nl_cb_set(cb, NL_CB_ACK, NL_CB_CUSTOM, ack_wait_handler, NULL);

	err = nl_recvmsgs(handle, cb);
	nl_cb_destroy(cb);

	return err;
}

/** @} */

/**
 * @name Netlink Family Translations
 * @{
 */

static struct trans_tbl nlfamilies[] = {
	__ADD(NETLINK_ROUTE,route)
	__ADD(NETLINK_W1,w1)
	__ADD(NETLINK_USERSOCK,usersock)
	__ADD(NETLINK_FIREWALL,firewall)
	__ADD(NETLINK_INET_DIAG,inetdiag)
	__ADD(NETLINK_NFLOG,nflog)
	__ADD(NETLINK_XFRM,xfrm)
	__ADD(NETLINK_SELINUX,selinux)
	__ADD(NETLINK_ISCSI,iscsi)
	__ADD(NETLINK_AUDIT,audit)
	__ADD(NETLINK_FIB_LOOKUP,fib_lookup)
	__ADD(NETLINK_CONNECTOR,connector)
	__ADD(NETLINK_NETFILTER,netfilter)
	__ADD(NETLINK_IP6_FW,ip6_fw)
	__ADD(NETLINK_DNRTMSG,dnrtmsg)
	__ADD(NETLINK_KOBJECT_UEVENT,kobject_uevent)
	__ADD(NETLINK_GENERIC,generic)
};

/**
 * Convert netlink family to character string.
 * @arg family		Netlink family.
 * @arg buf		Destination buffer.
 * @arg size		Size of destination buffer.
 *
 * Converts a netlink family to a character string and stores it in
 * the specified destination buffer.
 *
 * @return The destination buffer or the family encoded in hexidecimal
 *         form if no match was found.
 */
char * nl_nlfamily2str(int family, char *buf, size_t size)
{
	return __type2str(family, buf, size, nlfamilies,
			  ARRAY_SIZE(nlfamilies));
}

/**
 * Convert character string to netlink family.
 * @arg name		Name of netlink family.
 *
 * Converts the provided character string specifying a netlink
 * family to the corresponding numeric value.
 *
 * @return Numeric netlink family or a negative value if no match was found.
 */
int nl_str2nlfamily(const char *name)
{
	return __str2type(name, nlfamilies, ARRAY_SIZE(nlfamilies));
}