ibacm: Add Netlink socket to monitor IP address changes

Currently only reports events to the log.

Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Sean Hefty <sean.hefty@intel.com>

diff --git a/src/acm.c b/src/acm.c
index af1c66e595e761a706239b0cfaaee072ed26ee74..45f3ed9a4e6129bf80ec988f46348538cb35163c 100644 (file)
--- a/src/acm.c
+++ b/src/acm.c
@@ -49,6 +49,9 @@
 #include <net/if.h>
 #include <sys/ioctl.h>
 #include <net/if_arp.h>
+#include <netinet/in.h>
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
 #include "acm_mad.h"
 #include "acm_util.h"
 
@@ -214,6 +217,7 @@ static event_t timeout_event;
 static atomic_t wait_cnt;
 
 static SOCKET listen_socket;
+static SOCKET ip_mon_socket;
 static struct acm_client client[FD_SETSIZE - 1];
 
 static FILE *flog;
@@ -2389,6 +2393,92 @@ out:
                acm_disconnect_client(client);
 }
 
+static int acm_ipnl_create(void)
+{
+       struct sockaddr_nl addr;
+
+       if ((ip_mon_socket = socket(PF_NETLINK, SOCK_RAW | SOCK_NONBLOCK, NETLINK_ROUTE)) == -1) {
+               acm_log(0, "Failed to open NETLINK_ROUTE socket");
+               return EIO;
+       }
+
+       memset(&addr, 0, sizeof(addr));
+       addr.nl_family = AF_NETLINK;
+       addr.nl_groups = RTMGRP_LINK | RTMGRP_IPV4_IFADDR;
+
+       if (bind(ip_mon_socket, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
+               acm_log(0, "Failed to bind NETLINK_ROUTE socket");
+               return EIO;
+       }
+
+       return 0;
+}
+
+#define NL_MSG_BUF_SIZE 4096
+static void acm_ipnl_handler(void)
+{
+       int len;
+       char buffer[NL_MSG_BUF_SIZE];
+       struct nlmsghdr *nlh;
+       char name[IFNAMSIZ];
+       char ip_str[INET6_ADDRSTRLEN];
+
+       while ((len = recv(ip_mon_socket, buffer, NL_MSG_BUF_SIZE, 0)) > 0) {
+               nlh = (struct nlmsghdr *)buffer;
+               while ((NLMSG_OK(nlh, len)) && (nlh->nlmsg_type != NLMSG_DONE)) {
+                       struct ifaddrmsg *ifa = (struct ifaddrmsg *) NLMSG_DATA(nlh);
+                       struct ifinfomsg *ifi = (struct ifinfomsg *) NLMSG_DATA(nlh);
+                       struct rtattr *rth = IFA_RTA(ifa);
+                       int rtl = IFA_PAYLOAD(nlh);
+
+                       switch (nlh->nlmsg_type) {
+                       case RTM_NEWADDR:
+                       {
+                               if_indextoname(ifa->ifa_index, name);
+                               while (rtl && RTA_OK(rth, rtl)) {
+                                       if (rth->rta_type == IFA_LOCAL) {
+                                               acm_log(0, "Address added %s : %s\n",
+                                                       name, inet_ntop(ifa->ifa_family, RTA_DATA(rth),
+                                                       ip_str, sizeof(ip_str)));
+                                       }
+                                       rth = RTA_NEXT(rth, rtl);
+                               }
+                               break;
+                       }
+                       case RTM_DELADDR:
+                       {
+                               if_indextoname(ifa->ifa_index, name);
+                               while (rtl && RTA_OK(rth, rtl)) {
+                                       if (rth->rta_type == IFA_LOCAL) {
+                                               acm_log(0, "Address deleted %s : %s\n",
+                                                       name, inet_ntop(ifa->ifa_family, RTA_DATA(rth),
+                                                       ip_str, sizeof(ip_str)));
+                                       }
+                                       rth = RTA_NEXT(rth, rtl);
+                               }
+                               break;
+                       }
+                       case RTM_NEWLINK:
+                       {
+                               acm_log(2, "Link added : %s\n", if_indextoname(ifi->ifi_index, name));
+                               break;
+                       }
+                       case RTM_DELLINK:
+                       {
+                               acm_log(2, "Link removed : %s\n", if_indextoname(ifi->ifi_index, name));
+                               break;
+                       }
+                       default:
+                               acm_log(2, "unknown netlink message\n");
+                               break;
+                       }
+                       nlh = NLMSG_NEXT(nlh, len);
+               }
+       }
+       if (len < 0 && errno == ENOBUFS)
+               acm_log(0, "ENOBUFS returned from netlink... Resyncing all IP's\n");
+}
+
 static void acm_server(void)
 {
        fd_set readfds;
@@ -2407,6 +2497,9 @@ static void acm_server(void)
                FD_ZERO(&readfds);
                FD_SET(listen_socket, &readfds);
 
+               n = max(n, (int) ip_mon_socket);
+               FD_SET(ip_mon_socket, &readfds);
+
                for (i = 0; i < FD_SETSIZE - 1; i++) {
                        if (client[i].sock != INVALID_SOCKET) {
                                FD_SET(client[i].sock, &readfds);
@@ -2423,6 +2516,9 @@ static void acm_server(void)
                if (FD_ISSET(listen_socket, &readfds))
                        acm_svr_accept();
 
+               if (FD_ISSET(ip_mon_socket, &readfds))
+                       acm_ipnl_handler();
+
                for (i = 0; i < FD_SETSIZE - 1; i++) {
                        if (client[i].sock != INVALID_SOCKET &&
                                FD_ISSET(client[i].sock, &readfds)) {
@@ -3746,6 +3842,9 @@ int CDECL_FUNC main(int argc, char **argv)
                return -1;
        }
 
+       acm_log(1, "creating IP Netlink socket\n");
+       acm_ipnl_create();
+
        acm_activate_devices();
        acm_log(1, "starting timeout/retry thread\n");
        beginthread(acm_retry_handler, NULL);