static int
lookup_brc_multicast_group(int *multicast_group)
{
struct nl_sock *sock;
struct ofpbuf request, *reply;
struct nlattr *attrs[ARRAY_SIZE(brc_multicast_policy)];
int retval;
retval = nl_sock_create(NETLINK_GENERIC, &sock);
if (retval) {
return retval;
}
ofpbuf_init(&request, 0);
nl_msg_put_genlmsghdr(&request, 0, brc_family,
NLM_F_REQUEST, BRC_GENL_C_QUERY_MC, 1);
retval = nl_sock_transact(sock, &request, &reply);
ofpbuf_uninit(&request);
if (retval) {
nl_sock_destroy(sock);
return retval;
}
if (!nl_policy_parse(reply, NLMSG_HDRLEN + GENL_HDRLEN,
brc_multicast_policy, attrs,
ARRAY_SIZE(brc_multicast_policy))) {
nl_sock_destroy(sock);
ofpbuf_delete(reply);
return EPROTO;
}
*multicast_group = nl_attr_get_u32(attrs[BRC_GENL_A_MC_GROUP]);
nl_sock_destroy(sock);
ofpbuf_delete(reply);
return 0;
}
/* Looks up the Netlink multicast group and datapath index of a datapath
* by either the datapath index or name. If 'dp_idx' points to a value
* of '-1', then 'dp_name' is used to lookup the datapath. If successful,
* stores the multicast group in '*multicast_group' and the index in
* '*dp_idx' and returns 0. Otherwise, returns a positive errno value. */
static int
query_datapath(int *dp_idx, int *multicast_group, const char *dp_name)
{
struct nl_sock *sock;
struct ofpbuf request, *reply;
struct nlattr *attrs[ARRAY_SIZE(openflow_multicast_policy)];
int retval;
retval = nl_sock_create(NETLINK_GENERIC, 0, 0, 0, &sock);
if (retval) {
return retval;
}
ofpbuf_init(&request, 0);
nl_msg_put_genlmsghdr(&request, sock, 0, openflow_family, NLM_F_REQUEST,
DP_GENL_C_QUERY_DP, 1);
if (*dp_idx != -1) {
nl_msg_put_u32(&request, DP_GENL_A_DP_IDX, *dp_idx);
}
if (dp_name) {
nl_msg_put_string(&request, DP_GENL_A_DP_NAME, dp_name);
}
retval = nl_sock_transact(sock, &request, &reply);
ofpbuf_uninit(&request);
if (retval) {
nl_sock_destroy(sock);
return retval;
}
if (!nl_policy_parse(reply, NLMSG_HDRLEN + GENL_HDRLEN,
openflow_multicast_policy, attrs,
ARRAY_SIZE(openflow_multicast_policy))) {
nl_sock_destroy(sock);
ofpbuf_delete(reply);
return EPROTO;
}
*dp_idx = nl_attr_get_u32(attrs[DP_GENL_A_DP_IDX]);
*multicast_group = nl_attr_get_u32(attrs[DP_GENL_A_MC_GROUP]);
nl_sock_destroy(sock);
ofpbuf_delete(reply);
return 0;
}
/* Tries to receive an openflow message from datapath 'dp_idx' on 'sock'. If
* successful, stores the received message into '*msgp' and returns 0. The
* caller is responsible for destroying the message with ofpbuf_delete(). On
* failure, returns a positive errno value and stores a null pointer into
* '*msgp'.
*
* Only Netlink messages with embedded OpenFlow messages are accepted. Other
* Netlink messages provoke errors.
*
* If 'wait' is true, dpif_recv_openflow waits for a message to be ready;
* otherwise, returns EAGAIN if the 'sock' receive buffer is empty. */
int
dpif_recv_openflow(struct dpif *dp, int dp_idx, struct ofpbuf **bufferp,
bool wait)
{
struct nlattr *attrs[ARRAY_SIZE(openflow_policy)];
struct ofpbuf *buffer;
struct ofp_header *oh;
uint16_t ofp_len;
buffer = *bufferp = NULL;
do {
int retval;
do {
ofpbuf_delete(buffer);
retval = nl_sock_recv(dp->sock, &buffer, wait);
} while (retval == ENOBUFS
|| (!retval
&& (nl_msg_nlmsghdr(buffer)->nlmsg_type == NLMSG_DONE
|| nl_msg_nlmsgerr(buffer, NULL))));
if (retval) {
if (retval != EAGAIN) {
VLOG_WARN_RL(&rl, "dpif_recv_openflow: %s", strerror(retval));
}
return retval;
}
if (nl_msg_genlmsghdr(buffer) == NULL) {
VLOG_DBG_RL(&rl, "received packet too short for Generic Netlink");
goto error;
}
if (nl_msg_nlmsghdr(buffer)->nlmsg_type != openflow_family) {
VLOG_DBG_RL(&rl,
"received type (%"PRIu16") != openflow family (%d)",
nl_msg_nlmsghdr(buffer)->nlmsg_type, openflow_family);
goto error;
}
if (!nl_policy_parse(buffer, NLMSG_HDRLEN + GENL_HDRLEN,
openflow_policy, attrs,
ARRAY_SIZE(openflow_policy))) {
goto error;
}
} while (nl_attr_get_u32(attrs[DP_GENL_A_DP_IDX]) != dp_idx);
oh = buffer->data = (void *) nl_attr_get(attrs[DP_GENL_A_OPENFLOW]);
buffer->size = nl_attr_get_size(attrs[DP_GENL_A_OPENFLOW]);
ofp_len = ntohs(oh->length);
if (ofp_len != buffer->size) {
VLOG_WARN_RL(&rl,
"ofp_header.length %"PRIu16" != attribute length %zu\n",
ofp_len, buffer->size);
buffer->size = MIN(ofp_len, buffer->size);
}
*bufferp = buffer;
return 0;
error:
ofpbuf_delete(buffer);
return EPROTO;
}
bool parsed;
/* Policy for RTNLGRP_LINK messages.
*
* There are *many* more fields in these messages, but currently we
* only care about these fields. */
static const struct nl_policy policy[] = {
[IFLA_IFNAME] = { .type = NL_A_STRING, .optional = false },
[IFLA_MASTER] = { .type = NL_A_U32, .optional = true },
[IFLA_MTU] = { .type = NL_A_U32, .optional = true },
[IFLA_ADDRESS] = { .type = NL_A_UNSPEC, .optional = true },
};
struct nlattr *attrs[ARRAY_SIZE(policy)];
parsed = nl_policy_parse(buf, NLMSG_HDRLEN + sizeof(struct ifinfomsg),
policy, attrs, ARRAY_SIZE(policy));
if (parsed) {
const struct nlmsghdr *nlmsg;
const struct ifinfomsg *ifinfo;
nlmsg = buf->data;
ifinfo = ((const struct ifinfomsg *)
((const char *) buf->data + NLMSG_HDRLEN));
change->nlmsg_type = nlmsg->nlmsg_type;
change->ifi_index = ifinfo->ifi_index;
change->ifname = nl_attr_get_string(attrs[IFLA_IFNAME]);
change->ifi_flags = ifinfo->ifi_flags;
change->master_ifindex = (attrs[IFLA_MASTER]
? nl_attr_get_u32(attrs[IFLA_MASTER])
int
main(int argc OVS_UNUSED, char *argv[])
{
uint64_t buf_stub[4096 / 64];
struct nl_sock *sock;
struct ofpbuf buf;
int error;
set_program_name(argv[0]);
vlog_set_levels(NULL, VLF_ANY_FACILITY, VLL_DBG);
error = nl_sock_create(NETLINK_ROUTE, &sock);
if (error) {
ovs_fatal(error, "could not create rtnetlink socket");
}
error = nl_sock_join_mcgroup(sock, RTNLGRP_LINK);
if (error) {
ovs_fatal(error, "could not join RTNLGRP_LINK multicast group");
}
ofpbuf_use_stub(&buf, buf_stub, sizeof buf_stub);
for (;;) {
error = nl_sock_recv(sock, &buf, false);
if (error == EAGAIN) {
/* Nothing to do. */
} else if (error == ENOBUFS) {
ovs_error(0, "network monitor socket overflowed");
} else if (error) {
ovs_fatal(error, "error on network monitor socket");
} else {
struct iff_flag {
unsigned int flag;
const char *name;
};
static const struct iff_flag flags[] = {
{ IFF_UP, "UP", },
{ IFF_BROADCAST, "BROADCAST", },
#ifndef _WIN32
{ IFF_DEBUG, "DEBUG", },
#endif
{ IFF_LOOPBACK, "LOOPBACK", },
#ifndef _WIN32
{ IFF_POINTOPOINT, "POINTOPOINT", },
{ IFF_NOTRAILERS, "NOTRAILERS", },
#endif
{ IFF_RUNNING, "RUNNING", },
#ifndef _WIN32
{ IFF_NOARP, "NOARP", },
#endif
{ IFF_PROMISC, "PROMISC", },
#ifndef _WIN32
{ IFF_ALLMULTI, "ALLMULTI", },
{ IFF_MASTER, "MASTER", },
{ IFF_SLAVE, "SLAVE", },
#endif
{ IFF_MULTICAST, "MULTICAST", },
#ifndef _WIN32
{ IFF_PORTSEL, "PORTSEL", },
{ IFF_AUTOMEDIA, "AUTOMEDIA", },
{ IFF_DYNAMIC, "DYNAMIC", },
#endif
};
struct nlattr *attrs[ARRAY_SIZE(rtnlgrp_link_policy)];
struct nlmsghdr *nlh;
struct ifinfomsg *iim;
int i;
nlh = ofpbuf_at(&buf, 0, NLMSG_HDRLEN);
iim = ofpbuf_at(&buf, NLMSG_HDRLEN, sizeof *iim);
if (!iim) {
ovs_error(0, "received bad rtnl message (no ifinfomsg)");
continue;
}
if (!nl_policy_parse(&buf, NLMSG_HDRLEN + sizeof(struct ifinfomsg),
rtnlgrp_link_policy,
attrs, ARRAY_SIZE(rtnlgrp_link_policy))) {
ovs_error(0, "received bad rtnl message (policy)");
continue;
}
printf("netdev %s changed (%s):\n",
nl_attr_get_string(attrs[IFLA_IFNAME]),
(nlh->nlmsg_type == RTM_NEWLINK ? "RTM_NEWLINK"
#ifndef _WIN32
: nlh->nlmsg_type == RTM_DELLINK ? "RTM_DELLINK"
#endif
: nlh->nlmsg_type == RTM_GETLINK ? "RTM_GETLINK"
#ifndef _WIN32
: nlh->nlmsg_type == RTM_SETLINK ? "RTM_SETLINK"
#endif
: "other"));
printf("\tflags:");
for (i = 0; i < ARRAY_SIZE(flags); i++) {
if (iim->ifi_flags & flags[i].flag) {
printf(" %s", flags[i].name);
}
}
printf("\n");
if (attrs[IFLA_MASTER]) {
uint32_t idx = nl_attr_get_u32(attrs[IFLA_MASTER]);
char ifname[IFNAMSIZ];
#ifndef _WIN32
if (!if_indextoname(idx, ifname)) {
strcpy(ifname, "unknown");
}
#endif
printf("\tmaster=%"PRIu32" (%s)\n", idx, ifname);
}
}
nl_sock_wait(sock, POLLIN);
poll_block();
}
}
