summaryrefslogtreecommitdiffstats
path: root/watchlink/netlink_send.cc
diff options
context:
space:
mode:
Diffstat (limited to 'watchlink/netlink_send.cc')
-rw-r--r--watchlink/netlink_send.cc318
1 files changed, 318 insertions, 0 deletions
diff --git a/watchlink/netlink_send.cc b/watchlink/netlink_send.cc
new file mode 100644
index 00000000..3824c2ef
--- /dev/null
+++ b/watchlink/netlink_send.cc
@@ -0,0 +1,318 @@
+/*
+ * Module: netlink_send.cc
+ *
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+#include <errno.h>
+#include <arpa/inet.h>
+#include <linux/types.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
+#include <syslog.h>
+
+#include <vector>
+#include <string>
+#include <iostream>
+
+#include "netlink_utils.hh"
+#include "netlink_send.hh"
+
+using namespace std;
+
+
+/**
+ *
+ *
+ **/
+NetlinkSend::NetlinkSend(bool debug) : _debug(debug)
+{
+}
+
+
+/**
+ *
+ *
+ **/
+NetlinkSend::~NetlinkSend()
+{
+}
+
+/**
+ *
+ *
+ **/
+int
+NetlinkSend::send_set(int sock, int ifindex, uint32_t local_addr, uint32_t addr, int mask_len, int type)
+{
+ int ret;
+ struct sockaddr_nl snl;
+ struct {
+ struct nlmsghdr n;
+ struct ifaddrmsg ifa;
+ char buf[256];
+ } req;
+
+ /* Check netlink socket. */
+ if (sock < 0) {
+ syslog(LOG_ERR,"sock is not active, exiting");
+ cerr << "sock is not active, exiting" << endl;
+ return -1;
+ }
+
+ if (_debug) {
+ struct in_addr in;
+ in.s_addr = local_addr;
+ char *lbuf = inet_ntoa(in);
+
+ in.s_addr = addr;
+ char *buf = inet_ntoa(in);
+
+ char sbuf[1024];
+ sprintf(sbuf, "NetlinkSend::send_set(): %d, %s/%d, to this address: %s, on interface: %d",type,buf,mask_len,lbuf,ifindex);
+ cout << sbuf << endl;
+
+ syslog(LOG_INFO,sbuf);
+ }
+
+ memset(&req, 0, sizeof(req));
+
+ req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifaddrmsg));
+ req.n.nlmsg_flags = NLM_F_REQUEST;
+ req.n.nlmsg_pid = getpid();
+ req.n.nlmsg_type = type;
+ req.n.nlmsg_seq = time(NULL);
+ req.ifa.ifa_family = AF_INET;
+ req.ifa.ifa_index = ifindex;
+ req.ifa.ifa_prefixlen = mask_len;
+
+ // addr = htonl( addr );
+ addattr_l(&req.n, sizeof(req), IFA_LOCAL, &local_addr, sizeof(local_addr) );
+
+ in_addr_t broadcast_addr = ipv4_broadcast_addr(local_addr,mask_len);
+ addattr_l(&req.n, sizeof(req), IFA_BROADCAST, &broadcast_addr, sizeof(broadcast_addr) );
+
+ if (addr != -1 && local_addr != addr) {
+ addattr_l(&req.n, sizeof(req), IFA_ADDRESS, &addr, sizeof(addr) );
+ }
+
+ memset(&snl, 0, sizeof(snl));
+ snl.nl_family = AF_NETLINK;
+
+ ret = sendto (sock, (void*) &req, sizeof req, 0,
+ (struct sockaddr*) &snl, sizeof snl);
+ if (ret < 0) {
+ syslog(LOG_ERR,"netlink_send failed on send: %d, %d",ret,errno);
+ cerr << "netlink_send failed on send: " << ret << ", " << errno << endl;
+ return -1;
+ }
+ return 0;
+}
+
+/**
+ *
+ *
+ **/
+int
+NetlinkSend::send_set_route(int sock, int ifindex, uint32_t local_addr, uint32_t dst_addr, int mask_len, int type, int table, int rtn_type, int rt_scope)
+{
+ int ret;
+ struct sockaddr_nl snl;
+ struct {
+ struct nlmsghdr n;
+ struct rtmsg rt_message;
+ char buf[8192];
+ } req;
+ req.rt_message.rtm_table = 0;
+ req.rt_message.rtm_protocol = 0;
+ req.rt_message.rtm_scope = 0;
+ req.rt_message.rtm_type = 0;
+ req.rt_message.rtm_src_len = 0;
+ req.rt_message.rtm_dst_len = 0;
+ req.rt_message.rtm_tos = 0;
+
+ memset(&snl, 0, sizeof(snl));
+ snl.nl_family = AF_NETLINK;
+
+ /* Check netlink socket. */
+ if (sock < 0) {
+ syslog(LOG_ERR,"sock is not active, exiting");
+ cerr << "sock is not active, exiting" << endl;
+ return -1;
+ }
+
+ if (_debug) {
+ struct in_addr in;
+ in.s_addr = local_addr;
+ char *lbuf = inet_ntoa(in);
+
+ in.s_addr = dst_addr;
+ char *buf = inet_ntoa(in);
+
+ char sbuf[1024];
+ sprintf(sbuf, "NetlinkSend::send_set_route(): %d, %s/%d, to this address: %s, on interface: %d, for this table: ",type,buf,mask_len,lbuf,ifindex,table);
+ cout << sbuf << endl;
+
+ syslog(LOG_INFO,sbuf);
+ }
+
+ memset(&req, 0, sizeof(req));
+
+ req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
+ if (type == RTM_NEWROUTE) {
+ req.n.nlmsg_flags = NLM_F_REQUEST|NLM_F_CREATE|NLM_F_EXCL;
+ }
+ else {
+ req.n.nlmsg_flags = NLM_F_REQUEST;
+ }
+ req.n.nlmsg_pid = getpid();
+ req.n.nlmsg_type = type;
+ req.n.nlmsg_seq = time(NULL);
+
+ req.rt_message.rtm_family = AF_INET;
+ req.rt_message.rtm_dst_len = mask_len;
+ req.rt_message.rtm_table = table;
+ if (type == RTM_NEWROUTE) {
+ req.rt_message.rtm_protocol = RTPROT_KERNEL;
+ if (rt_scope != -1) {
+ req.rt_message.rtm_scope = rt_scope;//RT_SCOPE_HOST; //will need to pass this in to get RT_SCOPE_HOST
+ }
+ if (rtn_type != -1) {
+ req.rt_message.rtm_type = rtn_type;//RTN_LOCAL;
+ }
+ }
+ else {
+ req.rt_message.rtm_scope = RT_SCOPE_NOWHERE;
+ req.rt_message.rtm_type = RTN_UNSPEC;
+ }
+
+ addattr_l(&req.n, sizeof(req), RTA_PREFSRC, &local_addr, sizeof(local_addr));
+ addattr_l(&req.n, sizeof(req), RTA_DST, &dst_addr, sizeof(dst_addr));
+ addattr32(&req.n, sizeof(req), RTA_OIF, ifindex);
+
+ if (_debug) {
+ cout << "NetlinkSend::send_set_route():" << endl;
+ cout << " interface: " << ifindex << endl;
+ cout << " type: " << string(req.n.nlmsg_type == RTM_NEWROUTE ? string("RTM_NEWROUTE") : string("RTM_DELROUTE")) << endl;
+ cout << " flags: " << req.n.nlmsg_flags << endl;
+ cout << " protocol: " << int(req.rt_message.rtm_protocol) << endl;
+ cout << " scope: " << int(req.rt_message.rtm_scope) << endl;
+ cout << " addr(s): " << local_addr << ", " << dst_addr << ", " << mask_len << ", " << int(req.rt_message.rtm_dst_len) << endl;
+ cout << endl;
+ }
+
+ ret = sendto (sock, (void*) &req, sizeof req, 0,
+ (struct sockaddr*) &snl, sizeof snl);
+ if (ret < 0) {
+ syslog(LOG_ERR,"netlink_send_route failed on send: %d, %d",ret,errno);
+ cerr << "netlink_send_route failed on send: " << ret << ", " << errno << endl;
+ return -1;
+ }
+ return 0;
+}
+
+/**
+ *
+ *
+ **/
+int
+NetlinkSend::send_get(int sock, int type, int ifindex)
+{
+ int ret;
+ struct sockaddr_nl snl;
+ struct {
+ struct nlmsghdr n;
+ struct ifaddrmsg ifa;
+ char buf[256];
+ } req;
+
+ /* Check netlink socket. */
+ if (sock < 0) {
+ syslog(LOG_ERR,"sock is not active, exiting");
+ cerr << "sock is not active, exiting" << endl;
+ return -1;
+ }
+
+ if (_debug) {
+ char sbuf[1024];
+ sprintf(sbuf,"NetlinkSend::send_get(): type: %d, ifindex: %d",type,ifindex);
+ cout << sbuf << endl;
+ syslog(LOG_INFO,sbuf);
+ }
+
+ memset(&req, 0, sizeof(req));
+
+ req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifaddrmsg));
+ if (ifindex > -1) {
+ req.n.nlmsg_flags = NLM_F_REQUEST | NLM_F_MATCH;
+ }
+ else {
+ req.n.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP;
+ }
+ req.n.nlmsg_pid = getpid();
+ req.n.nlmsg_type = type;
+ req.n.nlmsg_seq = time(NULL);
+ req.ifa.ifa_family = AF_INET;
+ if (ifindex > -1) {
+ req.ifa.ifa_index = ifindex;
+ }
+
+ /*
+ note bug right now in that all interfaces are provided back when a specific index is requested
+ */
+ memset(&snl, 0, sizeof(snl));
+ snl.nl_family = AF_NETLINK;
+
+ ret = sendto (sock, (void*) &req, sizeof req, 0,
+ (struct sockaddr*) &snl, sizeof snl);
+ if (ret < 0) {
+ syslog(LOG_ERR,"netlink_send failed on send: %d, %d",ret,errno);
+ cerr << "netlink_send failed on send: " << ret << ", " << errno << endl;
+ return -1;
+ }
+ return 0;
+}
+
+/**
+ *
+ *
+ **/
+int
+NetlinkSend::addattr_l(struct nlmsghdr *n, int maxlen, int type, void *data, int alen)
+{
+ int len = RTA_LENGTH(alen);
+ struct rtattr *rta;
+
+ if ((int)NLMSG_ALIGN(n->nlmsg_len) + len > maxlen)
+ return -1;
+ rta = (struct rtattr*)(((char*)n) + NLMSG_ALIGN(n->nlmsg_len));
+ rta->rta_type = type;
+ rta->rta_len = len;
+ memcpy(RTA_DATA(rta), data, alen);
+ n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + len;
+ return 0;
+}
+
+int
+NetlinkSend::addattr32(struct nlmsghdr *n, int maxlen, int type, int data)
+{
+ int len;
+ struct rtattr *rta;
+
+ len = RTA_LENGTH (4);
+
+ if (NLMSG_ALIGN (n->nlmsg_len) + len > maxlen)
+ return -1;
+
+ rta = (struct rtattr *) (((char *) n) + NLMSG_ALIGN (n->nlmsg_len));
+ rta->rta_type = type;
+ rta->rta_len = len;
+ memcpy (RTA_DATA (rta), &data, 4);
+ n->nlmsg_len = NLMSG_ALIGN (n->nlmsg_len) + len;
+
+ return 0;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2025-09-14 15:36:26 +0000