face: make EthernetFace more robust against errors.
We now call .fail() instead of throwing an exception.
Also modernize the code with some C++11 features.
In particular, std::unique_ptr is now used to manage
the pcap instance.
Change-Id: I91200ff9ab64ddb2d86f082647043e42ca85f538
Refs: #1984
diff --git a/daemon/face/ethernet-face.cpp b/daemon/face/ethernet-face.cpp
index 4ffb9db..0e13844 100644
--- a/daemon/face/ethernet-face.cpp
+++ b/daemon/face/ethernet-face.cpp
@@ -64,6 +64,7 @@
const NetworkInterfaceInfo& interface,
const ethernet::Address& address)
: Face(FaceUri(address), FaceUri::fromDev(interface.name))
+ , m_pcap(nullptr, pcap_close)
, m_socket(socket)
#if defined(__linux__)
, m_interfaceIndex(interface.index)
@@ -76,7 +77,7 @@
<< m_srcAddress << " <--> " << m_destAddress);
pcapInit();
- int fd = pcap_get_selectable_fd(m_pcap);
+ int fd = pcap_get_selectable_fd(m_pcap.get());
if (fd < 0)
throw Error("pcap_get_selectable_fd() failed");
@@ -107,8 +108,6 @@
EthernetFace::~EthernetFace()
{
- onFail.clear(); // no reason to call onFail anymore
- close();
}
void
@@ -128,23 +127,25 @@
void
EthernetFace::close()
{
- if (m_pcap)
- {
- boost::system::error_code error;
- m_socket->close(error); // ignore errors
- pcap_close(m_pcap);
- m_pcap = 0;
+ if (!m_pcap)
+ return;
- fail("Face closed");
- }
+ NFD_LOG_INFO("[id:" << getId() << ",endpoint:" << m_interfaceName
+ << "] Closing face");
+
+ boost::system::error_code error;
+ m_socket->cancel(error); // ignore errors
+ m_socket->close(error); // ignore errors
+ m_pcap.reset(nullptr);
+
+ fail("Face closed");
}
void
EthernetFace::pcapInit()
{
- char errbuf[PCAP_ERRBUF_SIZE];
- errbuf[0] = '\0';
- m_pcap = pcap_create(m_interfaceName.c_str(), errbuf);
+ char errbuf[PCAP_ERRBUF_SIZE] = {};
+ m_pcap.reset(pcap_create(m_interfaceName.c_str(), errbuf));
if (!m_pcap)
throw Error("pcap_create(): " + std::string(errbuf));
@@ -153,31 +154,31 @@
// This corresponds to the BIOCIMMEDIATE ioctl on BSD-like systems (including OS X)
// where libpcap uses a BPF device. On Linux this forces libpcap not to use TPACKET_V3,
// even if the kernel supports it, thus preventing bug #1511.
- pcap_set_immediate_mode(m_pcap, 1);
+ pcap_set_immediate_mode(m_pcap.get(), 1);
#endif
- if (pcap_activate(m_pcap) < 0)
+ if (pcap_activate(m_pcap.get()) < 0)
throw Error("pcap_activate() failed");
- if (pcap_set_datalink(m_pcap, DLT_EN10MB) < 0)
- throw Error("pcap_set_datalink(): " + std::string(pcap_geterr(m_pcap)));
+ if (pcap_set_datalink(m_pcap.get(), DLT_EN10MB) < 0)
+ throw Error("pcap_set_datalink(): " + std::string(pcap_geterr(m_pcap.get())));
- if (pcap_setdirection(m_pcap, PCAP_D_IN) < 0)
+ if (pcap_setdirection(m_pcap.get(), PCAP_D_IN) < 0)
// no need to throw on failure, BPF will filter unwanted packets anyway
- NFD_LOG_WARN("pcap_setdirection(): " << pcap_geterr(m_pcap));
+ NFD_LOG_WARN("pcap_setdirection(): " << pcap_geterr(m_pcap.get()));
}
void
EthernetFace::setPacketFilter(const char* filterString)
{
bpf_program filter;
- if (pcap_compile(m_pcap, &filter, filterString, 1, PCAP_NETMASK_UNKNOWN) < 0)
- throw Error("pcap_compile(): " + std::string(pcap_geterr(m_pcap)));
+ if (pcap_compile(m_pcap.get(), &filter, filterString, 1, PCAP_NETMASK_UNKNOWN) < 0)
+ throw Error("pcap_compile(): " + std::string(pcap_geterr(m_pcap.get())));
- int ret = pcap_setfilter(m_pcap, &filter);
+ int ret = pcap_setfilter(m_pcap.get(), &filter);
pcap_freecode(&filter);
if (ret < 0)
- throw Error("pcap_setfilter(): " + std::string(pcap_geterr(m_pcap)));
+ throw Error("pcap_setfilter(): " + std::string(pcap_geterr(m_pcap.get())));
}
void
@@ -242,7 +243,7 @@
{
NFD_LOG_DEBUG("[id:" << getId() << ",endpoint:" << m_interfaceName
<< "] Falling back to promiscuous mode");
- pcap_set_promisc(m_pcap, 1);
+ pcap_set_promisc(m_pcap.get(), 1);
}
}
@@ -253,8 +254,7 @@
{
NFD_LOG_WARN("[id:" << getId() << ",endpoint:" << m_interfaceName
<< "] Trying to send on closed face");
- fail("Face closed");
- return;
+ return fail("Face closed");
}
/// \todo Fragmentation
@@ -283,14 +283,14 @@
buffer.prependByteArray(m_destAddress.data(), m_destAddress.size());
// send the packet
- int sent = pcap_inject(m_pcap, buffer.buf(), buffer.size());
+ int sent = pcap_inject(m_pcap.get(), buffer.buf(), buffer.size());
if (sent < 0)
{
- throw Error("pcap_inject(): " + std::string(pcap_geterr(m_pcap)));
+ return fail("pcap_inject(): " + std::string(pcap_geterr(m_pcap.get())));
}
else if (static_cast<size_t>(sent) < buffer.size())
{
- throw Error("Failed to send packet");
+ return fail("Failed to inject frame");
}
NFD_LOG_TRACE("[id:" << getId() << ",endpoint:" << m_interfaceName
@@ -301,56 +301,26 @@
void
EthernetFace::handleRead(const boost::system::error_code& error, size_t)
{
+ if (!m_pcap)
+ return fail("Face closed");
+
if (error)
return processErrorCode(error);
- pcap_pkthdr* pktHeader;
+ pcap_pkthdr* header;
const uint8_t* packet;
- int ret = pcap_next_ex(m_pcap, &pktHeader, &packet);
+ int ret = pcap_next_ex(m_pcap.get(), &header, &packet);
if (ret < 0)
{
- throw Error("pcap_next_ex(): " + std::string(pcap_geterr(m_pcap)));
+ return fail("pcap_next_ex(): " + std::string(pcap_geterr(m_pcap.get())));
}
else if (ret == 0)
{
- NFD_LOG_WARN("[id:" << getId() << ",endpoint:" << m_interfaceName
- << "] pcap_next_ex() timed out");
+ NFD_LOG_WARN("[id:" << getId() << ",endpoint:" << m_interfaceName << "] Read timeout");
}
else
{
- size_t length = pktHeader->caplen;
- if (length < ethernet::HDR_LEN + ethernet::MIN_DATA_LEN)
- throw Error("Received packet is too short");
-
- const ether_header* eh = reinterpret_cast<const ether_header*>(packet);
- if (ntohs(eh->ether_type) != ethernet::ETHERTYPE_NDN)
- throw Error("Unrecognized ethertype");
-
- packet += ethernet::HDR_LEN;
- length -= ethernet::HDR_LEN;
-
- /// \todo Reserve space in front and at the back
- /// of the underlying buffer
- Block element;
- bool isOk = Block::fromBuffer(packet, length, element);
- if (isOk)
- {
- NFD_LOG_TRACE("[id:" << getId() << ",endpoint:" << m_interfaceName
- << "] Received: " << element.size() << " bytes");
- this->getMutableCounters().getNInBytes() += element.size();
-
- if (!decodeAndDispatchInput(element))
- {
- NFD_LOG_WARN("[id:" << getId() << ",endpoint:" << m_interfaceName
- << "] Received unrecognized block of type " << element.type());
- // ignore unknown packet
- }
- }
- else
- {
- NFD_LOG_WARN("[id:" << getId() << ",endpoint:" << m_interfaceName
- << "] Received block is invalid or too large to process");
- }
+ processIncomingPacket(header, packet);
}
m_socket->async_read_some(boost::asio::null_buffers(),
@@ -360,18 +330,58 @@
}
void
-EthernetFace::processErrorCode(const boost::system::error_code& error)
+EthernetFace::processIncomingPacket(const pcap_pkthdr* header, const uint8_t* packet)
{
- if (error == boost::system::errc::operation_canceled)
- // when socket is closed by someone
- return;
-
- if (!m_pcap)
+ size_t length = header->caplen;
+ if (length < ethernet::HDR_LEN + ethernet::MIN_DATA_LEN)
{
- fail("Face closed");
+ NFD_LOG_WARN("[id:" << getId() << ",endpoint:" << m_interfaceName
+ << "] Received frame is too short (" << length << " bytes)");
return;
}
+ const ether_header* eh = reinterpret_cast<const ether_header*>(packet);
+
+ // assert in case BPF fails to filter unwanted frames
+ BOOST_ASSERT_MSG(ethernet::Address(eh->ether_dhost) == m_destAddress,
+ "Received frame addressed to a different multicast group");
+ BOOST_ASSERT_MSG(ethernet::Address(eh->ether_shost) != m_srcAddress,
+ "Received frame sent by this host");
+ BOOST_ASSERT_MSG(ntohs(eh->ether_type) == ethernet::ETHERTYPE_NDN,
+ "Received frame with unrecognized ethertype");
+
+ packet += ethernet::HDR_LEN;
+ length -= ethernet::HDR_LEN;
+
+ /// \todo Reserve space in front and at the back of the underlying buffer
+ Block element;
+ bool isOk = Block::fromBuffer(packet, length, element);
+ if (isOk)
+ {
+ NFD_LOG_TRACE("[id:" << getId() << ",endpoint:" << m_interfaceName
+ << "] Received: " << element.size() << " bytes");
+ this->getMutableCounters().getNInBytes() += element.size();
+
+ if (!decodeAndDispatchInput(element))
+ {
+ NFD_LOG_WARN("[id:" << getId() << ",endpoint:" << m_interfaceName
+ << "] Received unrecognized block of type " << element.type());
+ }
+ }
+ else
+ {
+ NFD_LOG_WARN("[id:" << getId() << ",endpoint:" << m_interfaceName
+ << "] Received block is invalid or too large to process");
+ }
+}
+
+void
+EthernetFace::processErrorCode(const boost::system::error_code& error)
+{
+ if (error == boost::asio::error::operation_aborted)
+ // cancel() has been called on the socket
+ return;
+
std::string msg;
if (error == boost::asio::error::eof)
{
@@ -380,11 +390,9 @@
}
else
{
- msg = "Receive operation failed, closing face: " + error.message();
+ msg = "Receive operation failed: " + error.message();
NFD_LOG_WARN("[id:" << getId() << ",endpoint:" << m_interfaceName << "] " << msg);
}
-
- close();
fail(msg);
}