Commit 0ca7dca4 authored by Tomek Mrugalski's avatar Tomek Mrugalski 🛰
Browse files

[1237] Initial interface detection implemented for Linux.

- Interface detection implemented for Linux.
- OS-specific defines added to configure.ac
- Added stub interface detection for BSD systems.
parent ea709c77
......@@ -367,6 +367,33 @@ AC_HEADER_STDBOOL
AC_TYPE_SIZE_T
# Detect OS type (it may be used to do OS-specific things, e.g.
# interface detection in DHCP)
AC_MSG_CHECKING(OS family)
system=`uname -s`
case $system in
Linux)
OS_TYPE="LINUX"
CPPFLAGS="$CPPFLAGS -DOS_LINUX"
;;
Darwin | FreeBSD | NetBSD | OpenBSD)
OS_TYPE="BSD"
CPPFLAGS="$CPPFLAGS -DOS_BSD"
;;
Solaris)
OS_TYPE="Solaris"
CPPFLAGS="$CPPFLAGS -DOS_SOLARIS"
;;
*)
OS_TYPE="Unknown"
AC_MSG_WARN("Unsupported OS: uname returned $system")
;;
esac
AC_MSG_RESULT($OS_TYPE)
AM_CONDITIONAL(OS_LINUX, test $OS_TYPE = LINUX)
AM_CONDITIONAL(OS_BSD, test $OS_TYPE = BSD)
AM_CONDITIONAL(OS_SOLARIS, test $OS_TYPE = Solaris)
AC_MSG_CHECKING(for sa_len in struct sockaddr)
AC_TRY_COMPILE([
......@@ -1079,6 +1106,7 @@ Flags:
CXXFLAGS: $CXXFLAGS
LDFLAGS: $LDFLAGS
B10_CXXFLAGS: $B10_CXXFLAGS
OS Family: $OS_TYPE
dnl includes too
Python: ${PYTHON_INCLUDES}
${PYTHON_CXXFLAGS}
......
......@@ -30,7 +30,17 @@ Dhcpv6Srv::Dhcpv6Srv() {
// first call to instance() will create IfaceMgr (it's a singleton)
// it may throw something if things go wrong
IfaceMgr::instance();
try {
IfaceMgr::instance();
} catch (const std::exception &e) {
cout << "Failed to instantiate InterfaceManager. Aborting." << endl;
shutdown = true;
}
if (IfaceMgr::instance().countIfaces() == 0) {
cout << "Failed to detect any network interfaces. Aborting." << endl;
shutdown = true;
}
/// @todo: instantiate LeaseMgr here once it is imlpemented.
......
......@@ -19,6 +19,15 @@ libdhcp_la_SOURCES += dhcp6.h dhcp4.h
libdhcp_la_SOURCES += pkt6.cc pkt6.h
libdhcp_la_SOURCES += pkt4.cc pkt4.h
if OS_LINUX
libdhcp_la_SOURCES += iface_mgr_linux.cc
endif
if OS_BSD
libdhcp_la_SOURCES += iface_mgr_bsd.cc
endif
EXTRA_DIST = README
#EXTRA_DIST += log_messages.mes
......
......@@ -52,8 +52,10 @@ IfaceMgr::instance() {
}
IfaceMgr::Iface::Iface(const std::string& name, int ifindex)
:name_(name), ifindex_(ifindex), mac_len_(0) {
:name_(name), ifindex_(ifindex), mac_len_(0), flag_loopback_(false),
flag_up_(false), flag_running_(false), flag_multicast_(false),
flag_broadcast_(false), flags_(0), hardware_type_(0)
{
memset(mac_, 0, sizeof(mac_));
}
......@@ -71,7 +73,7 @@ IfaceMgr::Iface::getPlainMac() const {
tmp << hex;
for (int i = 0; i < mac_len_; i++) {
tmp.width(2);
tmp << mac_[i];
tmp << int(mac_[i]);
if (i < mac_len_-1) {
tmp << ":";
}
......@@ -95,7 +97,7 @@ IfaceMgr::IfaceMgr()
detectIfaces();
if (!openSockets()) {
if (!openSockets6()) {
isc_throw(Unexpected, "Failed to open/bind sockets.");
}
} catch (const std::exception& ex) {
......@@ -105,7 +107,7 @@ IfaceMgr::IfaceMgr()
// interface detection is implemented. Otherwise
// it is not possible to run tests in a portable
// way (see detectIfaces() method).
// throw ex;
throw ex;
}
}
......@@ -115,7 +117,7 @@ IfaceMgr::~IfaceMgr() {
}
void
IfaceMgr::detectIfaces() {
IfaceMgr::stubDetectIfaces() {
string ifaceName, linkLocal;
// TODO do the actual detection. Currently interface detection is faked
......@@ -154,8 +156,13 @@ IfaceMgr::detectIfaces() {
}
}
bool
IfaceMgr::openSockets() {
#if !defined(OS_LINUX) && !defined(OS_BSD)
void IfaceMgr::detectIfaces() {
stubDetectIfaces();
}
#endif
bool IfaceMgr::openSockets6() {
int sock;
for (IfaceLst::iterator iface=ifaces_.begin();
......@@ -166,6 +173,11 @@ IfaceMgr::openSockets() {
addr!=iface->addrs_.end();
++addr) {
// skip IPv4 addresses
if (addr->getFamily() != AF_INET6) {
continue;
}
sock = openSocket(iface->name_, *addr,
DHCP6_SERVER_PORT);
if (sock<0) {
......@@ -194,14 +206,23 @@ IfaceMgr::printIfaces(std::ostream& out /*= std::cout*/) {
for (IfaceLst::const_iterator iface=ifaces_.begin();
iface!=ifaces_.end();
++iface) {
out << "Detected interface " << iface->getFullName() << endl;
out << "Detected interface " << iface->getFullName()
<< ", hwtype=" << iface->hardware_type_ << ", maclen=" << iface->mac_len_
<< ", mac=" << iface->getPlainMac() << endl;
out << "flags=" << hex << iface->flags_ << dec << "("
<< (iface->flag_loopback_?"LOOPBACK ":"")
<< (iface->flag_up_?"UP ":"")
<< (iface->flag_running_?"RUNNING ":"")
<< (iface->flag_multicast_?"MULTICAST ":"")
<< (iface->flag_broadcast_?"BROADCAST ":"")
<< ")" << endl;
out << " " << iface->addrs_.size() << " addr(s):" << endl;
for (Addr6Lst::const_iterator addr=iface->addrs_.begin();
addr != iface->addrs_.end();
++addr) {
out << " " << addr->toText() << endl;
}
out << " mac: " << iface->getPlainMac() << endl;
}
}
......
......@@ -54,6 +54,8 @@ public:
/// returns link-layer address a plain text
std::string getPlainMac() const;
void setFlags(uint32_t flags);
/// network interface name
std::string name_;
......@@ -69,6 +71,29 @@ public:
/// length of link-layer address (usually 6)
int mac_len_;
/// specifies if selected interface is loopback
bool flag_loopback_;
/// specifies if selected interface is up
bool flag_up_;
/// flag specifies if selected interface is running
/// (e.g. cable plugged in, wifi associated)
bool flag_running_;
/// flag specifies if selected interface is multicast capable
bool flag_multicast_;
/// flag specifies if selected interface is broadcast capable
bool flag_broadcast_;
/// interface flags (this value is as is returned by OS,
/// it may mean different things on different OSes)
uint32_t flags_;
/// hardware type
uint16_t hardware_type_;
/// socket used to sending data
int sendsock_;
......@@ -140,6 +165,11 @@ public:
/// @return Pkt6 object representing received packet (or NULL)
boost::shared_ptr<Pkt6> receive();
/// @brief returns number of detected interfaces
///
/// @return number of detected interfaces
uint16_t countIfaces() { return ifaces_.size(); }
// don't use private, we need derived classes in tests
protected:
......@@ -159,6 +189,15 @@ protected:
void
detectIfaces();
/// @brief Stub implementation of network interface detection.
///
/// This implementations reads a single line from interfaces.txt file
/// and pretends to detect such interface. First interface name and
/// link-local IPv6 address or IPv4 address is read from the
/// intefaces.txt file.
void
stubDetectIfaces();
///
/// Opens UDP/IPv6 socket and binds it to address, interface and port.
///
......@@ -199,7 +238,7 @@ protected:
private:
/// Opens sockets on detected interfaces.
bool
openSockets();
openSockets6();
/// creates a single instance of this class (a singleton implementation)
static void
......
// Copyright (C) 2011 Internet Systems Consortium, Inc. ("ISC")
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
// AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
// PERFORMANCE OF THIS SOFTWARE.
#include <dhcp6/iface_mgr.h>
#include <exceptions/exceptions.h>
using namespace std;
using namespace isc;
using namespace isc::asiolink;
using namespace isc::dhcp;
#if !defined(OS_BSD)
/// There are several detectIfaces() implementations for specific
/// Operating Systems. This one is specific to BSD. It works on
/// BSD only, so it does not make sense to try to compile it somewhere
/// else. In particular, Makefile.am includes only one iface_mgr_{OS_TYPE}.cc
/// file.
#error "Attempt to compile iface_mgr_bsd.cc on non-BSD system!"
#endif
namespace isc {
void
IfaceMgr::detectIfaces() {
// TODO do the actual detection on BSDs. Currently just calling
// stub implementation.
stubDetectIfaces();
}
}
// Copyright (C) 2011 Internet Systems Consortium, Inc. ("ISC")
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
// AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
// PERFORMANCE OF THIS SOFTWARE.
#include <dhcp/iface_mgr.h>
#include <exceptions/exceptions.h>
#include <net/if.h>
#include <linux/if_link.h>
#include <linux/rtnetlink.h>
using namespace std;
using namespace isc;
using namespace isc::asiolink;
using namespace isc::dhcp;
#if !defined(OS_LINUX)
/// There are several detectIfaces() implementations for specific
/// Operating Systems. This one is specific to Linux. It works on
/// Linux only, so it does not make sense to try to compile it somewhere
/// else. In particular, Makefile.am includes only one iface_mgr_{OS_TYPE}.cc
/// file.
#error "Attempt to compile iface_mgr_linux.cc on non-Linux system!"
#endif
struct rtnl_handle
{
int fd;
struct sockaddr_nl local;
struct sockaddr_nl peer;
__u32 seq;
__u32 dump;
};
struct nlmsg_list
{
struct nlmsg_list *next;
struct nlmsghdr h;
};
const int sndbuf = 32768;
const int rcvbuf = 32768;
namespace isc {
void rtnl_open_socket(struct rtnl_handle& handle) {
// equivalent of rtnl_open
handle.fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
if (handle.fd < 0) {
isc_throw(Unexpected, "Failed to create NETLINK socket.");
}
if (setsockopt(handle.fd, SOL_SOCKET, SO_SNDBUF, &sndbuf, sizeof(sndbuf)) < 0) {
isc_throw(Unexpected, "Failed to set send buffer in NETLINK socket.");
}
if (setsockopt(handle.fd, SOL_SOCKET, SO_RCVBUF, &sndbuf, sizeof(rcvbuf)) < 0) {
isc_throw(Unexpected, "Failed to set receive buffer in NETLINK socket.");
}
memset(&handle.local, 0, sizeof(handle.local));
handle.local.nl_family = AF_NETLINK;
handle.local.nl_groups = 0;
if (bind(handle.fd, (struct sockaddr*)&handle.local, sizeof(handle.local)) < 0) {
isc_throw(Unexpected, "Failed to bind netlink socket.");
}
socklen_t addr_len = sizeof(handle.local);
if (getsockname(handle.fd, (struct sockaddr*)&handle.local, &addr_len) < 0) {
isc_throw(Unexpected, "Getsockname for netlink socket failed.");
}
// just 2 sanity checks and we are done
if ( (addr_len != sizeof(handle.local)) ||
(handle.local.nl_family != AF_NETLINK) ) {
isc_throw(Unexpected, "getsockname() returned unexpected data for netlink socket.");
}
}
// sends request over NETLINK socket
void rtnl_send_request(struct rtnl_handle& handle,
int family, int type) {
struct {
struct nlmsghdr nlh;
struct rtgenmsg g;
} req;
struct sockaddr_nl nladdr;
memset(&nladdr, 0, sizeof(nladdr));
nladdr.nl_family = AF_NETLINK;
memset(&req, 0, sizeof(req));
req.nlh.nlmsg_len = sizeof(req);
req.nlh.nlmsg_type = type;
req.nlh.nlmsg_flags = NLM_F_ROOT|NLM_F_MATCH|NLM_F_REQUEST;
req.nlh.nlmsg_pid = 0;
req.nlh.nlmsg_seq = handle.dump = ++handle.seq;
req.g.rtgen_family = family;
int status = sendto(handle.fd, (void*)&req, sizeof(req), 0,
(struct sockaddr*)&nladdr, sizeof(nladdr));
if (status<0) {
isc_throw(Unexpected, "Failed to send " << sizeof(nladdr) << " bytes over netlink socket.");
}
}
void rtnl_store_reply(/*const struct sockaddr_nl *who,*/ struct nlmsghdr *n, struct nlmsg_list** linfo)
{
struct nlmsg_list *h;
struct nlmsg_list **lp;
h = (nlmsg_list*)malloc(n->nlmsg_len+sizeof(void*));
if (h == NULL) {
isc_throw(Unexpected, "Failed to allocate " << n->nlmsg_len+sizeof(void*)
<< " bytes.");
}
memcpy(&h->h, n, n->nlmsg_len);
h->next = NULL;
for (lp = linfo; *lp; lp = &(*lp)->next) /* NOTHING */;
*lp = h;
// ll_remember_index(who, n, NULL);
// return 0;
}
void parse_rtattr(struct rtattr *tb[], int max, struct rtattr *rta, int len)
{
memset(tb, 0, sizeof(struct rtattr *) * (max + 1));
while (RTA_OK(rta, len)) {
if (rta->rta_type <= max)
tb[rta->rta_type] = rta;
rta = RTA_NEXT(rta,len);
}
if (len) {
isc_throw(Unexpected, "Failed to parse RTATTR in netlink message.");
}
}
void ipaddrs_get(IfaceMgr::Iface& iface, struct nlmsg_list *ainfo) {
uint8_t addr[16];
struct rtattr * rta_tb[IFA_MAX+1];
for ( ;ainfo ; ainfo = ainfo->next) {
struct nlmsghdr *n = &ainfo->h;
struct ifaddrmsg *ifa = (ifaddrmsg*)NLMSG_DATA(n);
// these are not the addresses you are looking for
if ( ifa->ifa_index != iface.ifindex_) {
continue;
}
if ( ifa->ifa_family == AF_INET6 ) {
memset(rta_tb, 0, sizeof(rta_tb));
parse_rtattr(rta_tb, IFA_MAX, IFA_RTA(ifa), n->nlmsg_len - NLMSG_LENGTH(sizeof(*ifa)));
if (!rta_tb[IFA_LOCAL])
rta_tb[IFA_LOCAL] = rta_tb[IFA_ADDRESS];
if (!rta_tb[IFA_ADDRESS])
rta_tb[IFA_ADDRESS] = rta_tb[IFA_LOCAL];
memcpy(addr,(char*)RTA_DATA(rta_tb[IFLA_ADDRESS]),16);
IOAddress a = IOAddress::from_bytes(AF_INET6, addr);
iface.addrs_.push_back(a);
/// TODO: Read lifetimes of configured addresses
}
if ( ifa->ifa_family == AF_INET ) {
memset(rta_tb, 0, sizeof(rta_tb));
parse_rtattr(rta_tb, IFA_MAX, IFA_RTA(ifa), n->nlmsg_len - NLMSG_LENGTH(sizeof(*ifa)));
if (!rta_tb[IFA_LOCAL])
rta_tb[IFA_LOCAL] = rta_tb[IFA_ADDRESS];
if (!rta_tb[IFA_ADDRESS])
rta_tb[IFA_ADDRESS] = rta_tb[IFA_LOCAL];
memcpy(addr,(char*)RTA_DATA(rta_tb[IFLA_ADDRESS]),4);
IOAddress a = IOAddress::from_bytes(AF_INET, addr);
iface.addrs_.push_back(a);
}
}
}
void rtnl_process_reply(struct rtnl_handle &rth,
struct nlmsg_list *&info) {
struct sockaddr_nl nladdr;
struct iovec iov;
struct msghdr msg;
memset(&msg, 0, sizeof(struct msghdr));
msg.msg_name = &nladdr;
msg.msg_namelen = sizeof(nladdr);
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
char buf[rcvbuf];
iov.iov_base = buf;
while (1) {
int status;
struct nlmsghdr *h;
iov.iov_len = sizeof(buf);
status = recvmsg(rth.fd, &msg, 0);
if (status < 0) {
if (errno == EINTR)
continue;
isc_throw(Unexpected, "Overrun while processing reply from netlink socket.");
}
if (status == 0) {
isc_throw(Unexpected, "EOF while reading netlink socket.");
}
h = (struct nlmsghdr*)buf;
while (NLMSG_OK(h, status)) {
// why we received this anyway?
if (nladdr.nl_pid != 0 ||
h->nlmsg_pid != rth.local.nl_pid ||
h->nlmsg_seq != rth.dump) {
h = NLMSG_NEXT(h, status);
continue;
}
if (h->nlmsg_type == NLMSG_DONE) {
// end of message
return;
}
if (h->nlmsg_type == NLMSG_ERROR) {
struct nlmsgerr *err = (struct nlmsgerr*)NLMSG_DATA(h);
if (h->nlmsg_len < NLMSG_LENGTH(sizeof(struct nlmsgerr))) {
// we are really out of luck here. We can't even say what is
// wrong as error message is truncated. D'oh.
isc_throw(Unexpected, "Netlink reply read failed.");
} else {
isc_throw(Unexpected, "Netlink reply read error " << -err->error);
}
// never happens we throw before we reach here
return;
}
// store the data
rtnl_store_reply(/*&nladdr,*/ h, &info);
h = NLMSG_NEXT(h, status);
}
if (msg.msg_flags & MSG_TRUNC) {
isc_throw(Unexpected, "Message received over netlink truncated.");
}
if (status) {
isc_throw(Unexpected, "Trailing garbage of " << status << " bytes received over netlink.");
}
}
}
void release_list(struct nlmsg_list *n) {
struct nlmsg_list *tmp;
while (n) {
tmp = n->next;
free(n);
n = tmp;
}
}
void
IfaceMgr::detectIfaces() {
cout << "Linux: detecting interfaces." << endl;
struct nlmsg_list *linfo = NULL;
struct nlmsg_list *ainfo = NULL;
struct nlmsg_list *l = NULL;
struct rtnl_handle rth;
/* required to display information about interface */
struct ifinfomsg *ifi = NULL;
struct rtattr * tb[IFLA_MAX+1];
int len = 0;
memset(tb, 0, sizeof(tb));
memset(&rth,0, sizeof(rth));
// open socket
rtnl_open_socket(rth);
// now we have open functional socket, let's use it!
rtnl_send_request(rth, AF_PACKET, RTM_GETLINK);
// process reply
rtnl_process_reply(rth, linfo);
//rtnl_dump_filter(&rth, store_nlmsg, &linfo, NULL, NULL);
/* 2nd attribute: AF_UNSPEC, AF_INET, AF_INET6 */
rtnl_send_request(rth, AF_UNSPEC, RTM_GETADDR);
rtnl_process_reply(rth, ainfo);
/* build list with interface names */
for (l=linfo; l; l = l->next) {
ifi = (ifinfomsg*)NLMSG_DATA(&l->h);
len = (&l->h)->nlmsg_len;
len -= NLMSG_LENGTH(sizeof(*ifi));
parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), len);
Iface* iface = new Iface(string( (char*)RTA_DATA(tb[IFLA_IFNAME])), ifi->ifi_index);