struct lldpd_netlink {
int nl_socket;
- int can_increase; /* Can we increase the netlink socket size? */
+ int nl_socket_recv_size;
/* Cache */
struct interfaces_device_list *devices;
struct interfaces_address_list *addresses;
};
+/**
+ * Set netlink socket buffer size.
+ *
+ * This returns the effective size on success. If the provided value is 0, this
+ * returns the current size instead. It returns -1 on system errors and -2 if
+ * the size was not changed appropriately (when reaching the max).
+ */
static int
-netlink_socket_set_buffer_sizes(int s, int sndbuf, int rcvbuf)
+netlink_socket_set_buffer_size(int s, int optname, const char *optname_str, int bufsize)
{
socklen_t size = sizeof(int);
int got = 0;
- if (sndbuf > 0 && setsockopt(s, SOL_SOCKET, SO_SNDBUF, &sndbuf, sizeof(sndbuf)) < 0) {
- log_warn("netlink", "unable to set SO_SNDBUF to '%d'", sndbuf);
- return -1;
- }
-
- if (rcvbuf > 0 && setsockopt(s, SOL_SOCKET, SO_RCVBUF, &rcvbuf, sizeof(rcvbuf)) < 0) {
- log_warn("netlink", "unable to set SO_RCVBUF to '%d'", rcvbuf);
+ if (bufsize > 0 && setsockopt(s, SOL_SOCKET, optname, &bufsize, sizeof(bufsize)) < 0) {
+ log_warn("netlink", "unable to set %s to '%d'", optname_str, bufsize);
return -1;
}
* `net.core.wmem_max`. This it the easiest [probably sanest too]
* to validate that our socket buffers were set properly.
*/
- if (sndbuf > 0) {
- if (getsockopt(s, SOL_SOCKET, SO_SNDBUF, &got, &size) < 0) {
- log_warn("netlink", "unable to get SO_SNDBUF");
- } else {
- if (got < sndbuf)
- log_warnx("netlink", "tried to set SO_SNDBUF to '%d' "
- "but got '%d'", sndbuf, got);
- }
- }
-
- if (rcvbuf > 0) {
- if (getsockopt(s, SOL_SOCKET, SO_RCVBUF, &got, &size) < 0) {
- log_warn("netlink", "unable to get SO_RCVBUF");
- } else {
- if (got < rcvbuf)
- log_warnx("netlink", "tried to set SO_RCVBUF to '%d' "
- "but got '%d'", rcvbuf, got);
- }
- }
-
- return 0;
-}
-
-/**
- * Double the size of the receive netlink send buffer.
- *
- * Returns 0 on success, -1 on system error, 1 when we were unable to grow the
- * buffer more.
- */
-static int
-netlink_socket_double_buffer_sizes(int s, int max)
-{
- socklen_t size = sizeof(int);
- int current = 0, got = 0;
- if (getsockopt(s, SOL_SOCKET, SO_RCVBUF, ¤t, &size) < 0) {
- log_warn("netlink", "unable to get SO_RCVBUF");
+ if (getsockopt(s, SOL_SOCKET, optname, &got, &size) < 0) {
+ log_warn("netlink", "unable to get %s", optname_str);
return -1;
}
- if (current < max) {
- current *= 2;
- if (current > max)
- current = max;
- if (setsockopt(s, SOL_SOCKET, SO_RCVBUF, ¤t, sizeof(current)) < 0) {
- log_warn("netlink", "unable to set SO_RCVBUF to '%d'", current);
- return -1;
- }
- if (getsockopt(s, SOL_SOCKET, SO_RCVBUF, &got, &size) < 0) {
- log_warn("netlink", "unable to get SO_RCVBUF");
- return -1;
- }
- if (got < current) {
- log_warnx("netlink", "tried to set SO_RCVBUF to '%d' "
- "but got '%d'", current, got);
- return 1; /* Assume we got the maximum */
- }
- log_debug("netlink", "increased SO_RCVBUF to %d", current);
- return 0;
+ if (bufsize > 0 && got < bufsize) {
+ log_warnx("netlink", "tried to set %s to '%d' "
+ "but got '%d'", optname_str, bufsize, got);
+ return -2;
}
- return 1; /* Maximum alredy reached */
+
+ return got;
}
/**
*
* @param protocol Which protocol to use (eg NETLINK_ROUTE).
* @param groups Which groups we want to subscribe to
- * @return The opened socket or -1 on error.
+ * @return 0 on success, -1 otherwise
*/
static int
-netlink_connect(int protocol, unsigned groups)
+netlink_connect(struct lldpd *cfg, int protocol, unsigned groups)
{
int s;
struct sockaddr_nl local = {
log_warn("netlink", "unable to open netlink socket");
return -1;
}
- if (netlink_socket_set_buffer_sizes(s,
- NETLINK_SEND_BUFSIZE, NETLINK_RECEIVE_BUFSIZE) < 0)
+ if (NETLINK_SEND_BUFSIZE &&
+ netlink_socket_set_buffer_size(s,
+ SO_SNDBUF, "SO_SNDBUF", NETLINK_SEND_BUFSIZE) == -1)
return -1;
+
+ int rc = netlink_socket_set_buffer_size(s,
+ SO_RCVBUF, "SO_RCVBUF", NETLINK_RECEIVE_BUFSIZE);
+ switch (rc) {
+ case -1: return -1;
+ case -2: cfg->g_netlink->nl_socket_recv_size = 0; break;
+ default: cfg->g_netlink->nl_socket_recv_size = rc; break;
+ }
if (groups && bind(s, (struct sockaddr *)&local, sizeof(struct sockaddr_nl)) < 0) {
log_warn("netlink", "unable to bind netlink socket");
close(s);
return -1;
}
- return s;
+ cfg->g_netlink->nl_socket = s;
+ return 0;
}
/**
/**
* Receive netlink answer from the kernel.
*
- * @param s the netlink socket
* @param ifs list to store interface list or NULL if we don't
* @param ifas list to store address list or NULL if we don't
* @return 0 on success, -1 on error
*/
static int
-netlink_recv(int s,
+netlink_recv(struct lldpd *cfg,
struct interfaces_device_list *ifs,
- struct interfaces_address_list *ifas,
- int *can_increase)
+ struct interfaces_address_list *ifas)
{
int end = 0, ret = 0;
int flags = MSG_PEEK | MSG_TRUNC;
struct iovec iov;
int link_update = 0;
+ int s = cfg->g_netlink->nl_socket;
struct interfaces_device *ifdold;
struct interfaces_device *ifdnew;
ret = 0;
goto out;
}
- if (errno == ENOBUFS && *can_increase) {
- switch (netlink_socket_double_buffer_sizes(s,
- NETLINK_MAX_RECEIVE_BUFSIZE)) {
- case -1: break;
- case 0:
- log_info("netlink", "netlink receive buffer too small, retry with larger one");
+ int rsize = cfg->g_netlink->nl_socket_recv_size;
+ if (errno == ENOBUFS &&
+ rsize > 0 && rsize < NETLINK_MAX_RECEIVE_BUFSIZE) {
+ /* Try to increase buffer size */
+ rsize *= 2;
+ if (rsize > NETLINK_MAX_RECEIVE_BUFSIZE) {
+ rsize = NETLINK_MAX_RECEIVE_BUFSIZE;
+ }
+ int rc = netlink_socket_set_buffer_size(s,
+ SO_RCVBUF, "SO_RCVBUF",
+ rsize);
+ if (rc < 0)
+ cfg->g_netlink->nl_socket_recv_size = 0;
+ else
+ cfg->g_netlink->nl_socket_recv_size = rsize;
+ if (rc > 0 || rc == -2) {
+ log_info("netlink",
+ "netlink receive buffer too small, retry with larger one (%d)",
+ rsize);
flags = 0;
goto retry;
- case 1:
- *can_increase = 0;
- break;
}
}
log_warn("netlink", "unable to receive netlink answer");
/**
* Subscribe to link changes.
*
- * @return The socket we should listen to for changes.
+ * @return 0 on success, -1 otherwise
*/
-int
-netlink_subscribe_changes()
+static int
+netlink_subscribe_changes(struct lldpd *cfg)
{
unsigned int groups;
netlink_group_mask(RTNLGRP_IPV4_IFADDR) |
netlink_group_mask(RTNLGRP_IPV6_IFADDR);
- return netlink_connect(NETLINK_ROUTE, groups);
+ return netlink_connect(cfg, NETLINK_ROUTE, groups);
}
/**
{
if (cfg->g_netlink == NULL)
return;
- netlink_recv(cfg->g_netlink->nl_socket,
+ netlink_recv(cfg,
cfg->g_netlink->devices,
- cfg->g_netlink->addresses,
- &cfg->g_netlink->can_increase);
+ cfg->g_netlink->addresses);
}
/**
/* Connect to netlink (by requesting to get notified on updates) and
* request updated information right now */
- int s = cfg->g_netlink->nl_socket = netlink_subscribe_changes();
+ if (netlink_subscribe_changes(cfg) == -1)
+ goto end;
struct interfaces_address_list *ifaddrs = cfg->g_netlink->addresses =
malloc(sizeof(struct interfaces_address_list));
}
TAILQ_INIT(ifs);
- cfg->g_netlink->can_increase = 1;
- if (netlink_send(s, RTM_GETADDR, AF_UNSPEC, 1) == -1)
+ if (netlink_send(cfg->g_netlink->nl_socket, RTM_GETADDR, AF_UNSPEC, 1) == -1)
goto end;
- netlink_recv(s, NULL, ifaddrs, &cfg->g_netlink->can_increase);
- if (netlink_send(s, RTM_GETLINK, AF_PACKET, 2) == -1)
+ netlink_recv(cfg, NULL, ifaddrs);
+ if (netlink_send(cfg->g_netlink->nl_socket, RTM_GETLINK, AF_PACKET, 2) == -1)
goto end;
- netlink_recv(s, ifs, NULL, &cfg->g_netlink->can_increase);
+ netlink_recv(cfg, ifs, NULL);
/* Listen to any future change */
cfg->g_iface_cb = netlink_change_cb;
- if (levent_iface_subscribe(cfg, s) == -1) {
+ if (levent_iface_subscribe(cfg, cfg->g_netlink->nl_socket) == -1) {
goto end;
}
projects / thirdparty / lldpd.git / commitdiff
