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/*
* This ought to be provided by libnl
*/
#include <asm/errno.h>
#include <netlink/genl/genl.h>
#include <netlink/genl/family.h>
#include <netlink/genl/ctrl.h>
#include <netlink/msg.h>
#include <netlink/attr.h>
#include <linux/genetlink.h>
#include "iw.h"
static int error_handler(struct sockaddr_nl *nla, struct nlmsgerr *err,
void *arg)
{
int *ret = arg;
*ret = err->error;
return NL_STOP;
}
static int ack_handler(struct nl_msg *msg, void *arg)
{
int *ret = arg;
*ret = 0;
return NL_STOP;
}
struct handler_args {
const char *group;
int id;
};
static int family_handler(struct nl_msg *msg, void *arg)
{
struct handler_args *grp = arg;
struct nlattr *tb[CTRL_ATTR_MAX + 1];
struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
struct nlattr *mcgrp;
int rem_mcgrp;
nla_parse(tb, CTRL_ATTR_MAX, genlmsg_attrdata(gnlh, 0),
genlmsg_attrlen(gnlh, 0), NULL);
if (!tb[CTRL_ATTR_MCAST_GROUPS])
return NL_SKIP;
nla_for_each_nested(mcgrp, tb[CTRL_ATTR_MCAST_GROUPS], rem_mcgrp) {
struct nlattr *tb_mcgrp[CTRL_ATTR_MCAST_GRP_MAX + 1];
nla_parse(tb_mcgrp, CTRL_ATTR_MCAST_GRP_MAX,
nla_data(mcgrp), nla_len(mcgrp), NULL);
if (!tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME] ||
!tb_mcgrp[CTRL_ATTR_MCAST_GRP_ID])
continue;
if (strncmp(nla_data(tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME]),
grp->group, nla_len(tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME])))
continue;
grp->id = nla_get_u32(tb_mcgrp[CTRL_ATTR_MCAST_GRP_ID]);
break;
}
return NL_SKIP;
}
int nl_get_multicast_id(struct nl_sock *sock, const char *family, const char *group)
{
struct nl_msg *msg;
struct nl_cb *cb;
int ret, ctrlid;
struct handler_args grp = {
.group = group,
.id = -ENOENT,
};
msg = nlmsg_alloc();
if (!msg)
return -ENOMEM;
cb = nl_cb_alloc(NL_CB_DEFAULT);
if (!cb) {
ret = -ENOMEM;
goto out_fail_cb;
}
ctrlid = genl_ctrl_resolve(sock, "nlctrl");
genlmsg_put(msg, 0, 0, ctrlid, 0,
0, CTRL_CMD_GETFAMILY, 0);
ret = -ENOBUFS;
NLA_PUT_STRING(msg, CTRL_ATTR_FAMILY_NAME, family);
ret = nl_send_auto_complete(sock, msg);
if (ret < 0)
goto out;
ret = 1;
nl_cb_err(cb, NL_CB_CUSTOM, error_handler, &ret);
nl_cb_set(cb, NL_CB_ACK, NL_CB_CUSTOM, ack_handler, &ret);
nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, family_handler, &grp);
while (ret > 0)
nl_recvmsgs(sock, cb);
if (ret == 0)
ret = grp.id;
nla_put_failure:
out:
nl_cb_put(cb);
out_fail_cb:
nlmsg_free(msg);
return ret;
}
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