static int nl_msg_out_handler_debug(struct nl_msg *msg, void *arg)
{
FILE *ofd = arg ? arg : stderr;
fprintf(ofd, "-- Debug: Sent Message:\n");
nl_msg_dump(msg, ofd);
return NL_OK;
}
static int message_dumper (struct nl_msg *msg, void *arg)
{
int protocol;
protocol = *(int *) arg;
fprintf (stderr, "Setting msg proto to %d\n", protocol);
nlmsg_set_proto (msg, protocol);
nl_msg_dump (msg, stderr);
return NL_OK;
}
static int cb_handler(struct nl_msg * msg, void * arg)
{
* (int*) arg = 123; // cbarg
struct nlmsghdr * hdr = nlmsg_hdr(msg);
struct genlmsghdr * gnlh = nlmsg_data(hdr);
int valid =
genlmsg_validate(hdr, 0, DEMO_ATTR_MAX, demo_gnl_policy);
printf("valid %d %s\n", valid, valid ? "ERROR" : "OK");
// one way
struct nlattr * attrs[DEMO_ATTR_MAX + 1];
if (genlmsg_parse(hdr, 0, attrs, DEMO_ATTR_MAX, demo_gnl_policy) < 0)
{
printf("genlsmg_parse ERROR\n");
}
else
{
printf("genlsmg_parse OK\n");
printf("attr1 %s\n", nla_get_string(attrs[DEMO_ATTR1_STRING]));
printf("attr2 %x\n", nla_get_u16(attrs[DEMO_ATTR2_UINT16]));
struct attr_custom * cp = (struct attr_custom *) nla_data(attrs[DEMO_ATTR3_CUSTOM]);
printf("attr3 %d %ld %f %lf\n", cp->a, cp->b, cp->c,cp->d);
}
// another way
printf("gnlh->cmd %d\n", gnlh->cmd); //--- DEMO_CMD_ECHO
int remaining = genlmsg_attrlen(gnlh, 0);
struct nlattr * attr = genlmsg_attrdata(gnlh, 0);
while (nla_ok(attr, remaining))
{
printf("remaining %d\n", remaining);
printf("attr @ %p\n", attr); // nla_get_string(attr)
attr = nla_next(attr, &remaining);
}
nl_msg_dump(msg, stderr);
return NL_STOP;
}
static int event_input(struct nl_msg *msg, void *arg)
{
struct nl_cache_mngr *mngr = arg;
int protocol = nlmsg_get_proto(msg);
int type = nlmsg_hdr(msg)->nlmsg_type;
struct nl_cache_ops *ops;
int i, n;
struct nl_parser_param p = {
.pp_cb = include_cb,
};
NL_DBG(2, "Cache manager %p, handling new message %p as event\n",
mngr, msg);
#ifdef NL_DEBUG
if (nl_debug >= 4)
nl_msg_dump(msg, stderr);
#endif
if (mngr->cm_protocol != protocol)
BUG();
for (i = 0; i < mngr->cm_nassocs; i++) {
if (mngr->cm_assocs[i].ca_cache) {
ops = mngr->cm_assocs[i].ca_cache->c_ops;
for (n = 0; ops->co_msgtypes[n].mt_id >= 0; n++)
if (ops->co_msgtypes[n].mt_id == type)
goto found;
}
}
return NL_SKIP;
found:
NL_DBG(2, "Associated message %p to cache %p\n",
msg, mngr->cm_assocs[i].ca_cache);
p.pp_arg = &mngr->cm_assocs[i];
return nl_cache_parse(ops, NULL, nlmsg_hdr(msg), &p);
}
static int rtnl_raw_parse_cb(struct nl_msg *msg, void *arg)
{
struct nl_lookup_arg *lookup_arg = (struct nl_lookup_arg *)arg;
struct usnic_rtnl_sk *unlsk = lookup_arg->unlsk;
struct nlmsghdr *nlm_hdr = nlmsg_hdr(msg);
struct rtmsg *rtm;
struct nlattr *tb[RTA_MAX + 1];
int found = 0;
int err;
#if WANT_DEBUG_MSGS
nl_msg_dump(msg, stderr);
#endif /* WANT_DEBUG_MSGS */
lookup_arg->nh_addr = 0;
lookup_arg->found = 0;
lookup_arg->replied = 0;
lookup_arg->msg_count++;
if (nlm_hdr->nlmsg_pid != nl_socket_get_local_port(unlsk->nlh)
|| nlm_hdr->nlmsg_seq != unlsk->seq) {
usnic_err("Not an expected reply msg pid: %u local pid: %u "
"msg seq: %u expected seq: %u\n",
nlm_hdr->nlmsg_pid, nl_socket_get_local_port(unlsk->nlh),
nlm_hdr->nlmsg_seq, unlsk->seq);
return NL_SKIP;
}
lookup_arg->replied = 1;
if (nlm_hdr->nlmsg_type == NLMSG_ERROR) {
struct nlmsgerr *e = (struct nlmsgerr *)nlmsg_data(nlm_hdr);
if (nlm_hdr->nlmsg_len >= (__u32)nlmsg_msg_size(sizeof(*e))) {
usnic_err("Received a netlink error message %d\n",
e->error);
}
else {
usnic_err("Received a truncated netlink error message\n");
}
return NL_STOP;
}
if (nlm_hdr->nlmsg_type != RTM_NEWROUTE) {
usnic_err("Received an invalid route request reply message\n");
return NL_STOP;
}
rtm = nlmsg_data(nlm_hdr);
if (rtm->rtm_family != AF_INET) {
usnic_err("RTM message contains invalid AF family\n");
return NL_STOP;
}
init_route_policy(route_policy);
err = nlmsg_parse(nlm_hdr, sizeof(struct rtmsg), tb, RTA_MAX,
route_policy);
if (err < 0) {
usnic_err("nlmsg parse error %d\n", err);
return NL_STOP;
}
if (tb[RTA_OIF]) {
if (nla_get_u32(tb[RTA_OIF]) == (uint32_t)lookup_arg->oif)
found = 1;
else
usnic_err("Retrieved route has a different outgoing interface %d (expected %d)\n",
nla_get_u32(tb[RTA_OIF]),
lookup_arg->oif);
}
if (found && tb[RTA_METRICS]) {
lookup_arg->metric = (int)nla_get_u32(tb[RTA_METRICS]);
}
if (found && tb[RTA_GATEWAY])
lookup_arg->nh_addr = nla_get_u32(tb[RTA_GATEWAY]);
lookup_arg->found = found;
return NL_STOP;
}