Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 1 | /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */ |
| 2 | /* |
| 3 | * Copyright (c) 2013-2018 Regents of the University of California. |
| 4 | * |
| 5 | * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions). |
| 6 | * |
| 7 | * ndn-cxx library is free software: you can redistribute it and/or modify it under the |
| 8 | * terms of the GNU Lesser General Public License as published by the Free Software |
| 9 | * Foundation, either version 3 of the License, or (at your option) any later version. |
| 10 | * |
| 11 | * ndn-cxx library is distributed in the hope that it will be useful, but WITHOUT ANY |
| 12 | * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A |
| 13 | * PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. |
| 14 | * |
| 15 | * You should have received copies of the GNU General Public License and GNU Lesser |
| 16 | * General Public License along with ndn-cxx, e.g., in COPYING.md file. If not, see |
| 17 | * <http://www.gnu.org/licenses/>. |
| 18 | * |
| 19 | * See AUTHORS.md for complete list of ndn-cxx authors and contributors. |
| 20 | * |
| 21 | * @author Davide Pesavento <davide.pesavento@lip6.fr> |
| 22 | */ |
| 23 | |
| 24 | #include "netlink-socket.hpp" |
| 25 | #include "netlink-message.hpp" |
| 26 | #include "../../util/logger.hpp" |
| 27 | #include "../../util/time.hpp" |
| 28 | |
| 29 | #include <cerrno> |
Davide Pesavento | 1077499 | 2018-08-19 18:47:50 -0400 | [diff] [blame^] | 30 | #include <linux/genetlink.h> |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 31 | #include <sys/socket.h> |
| 32 | |
| 33 | #include <boost/asio/write.hpp> |
| 34 | |
| 35 | #ifndef SOL_NETLINK |
| 36 | #define SOL_NETLINK 270 |
| 37 | #endif |
| 38 | #ifndef RTEXT_FILTER_SKIP_STATS |
| 39 | #define RTEXT_FILTER_SKIP_STATS (1 << 3) |
| 40 | #endif |
| 41 | |
| 42 | NDN_LOG_INIT(ndn.NetworkMonitor); |
| 43 | |
| 44 | namespace ndn { |
| 45 | namespace net { |
| 46 | |
| 47 | NetlinkSocket::NetlinkSocket(boost::asio::io_service& io) |
| 48 | : m_sock(make_shared<boost::asio::posix::stream_descriptor>(io)) |
| 49 | , m_pid(0) |
| 50 | , m_seqNum(static_cast<uint32_t>(time::system_clock::now().time_since_epoch().count())) |
| 51 | , m_buffer(16 * 1024) // 16 KiB |
| 52 | { |
| 53 | } |
| 54 | |
| 55 | NetlinkSocket::~NetlinkSocket() |
| 56 | { |
| 57 | boost::system::error_code ec; |
| 58 | m_sock->close(ec); |
| 59 | } |
| 60 | |
| 61 | void |
| 62 | NetlinkSocket::open(int protocol) |
| 63 | { |
| 64 | int fd = ::socket(AF_NETLINK, SOCK_RAW | SOCK_CLOEXEC, protocol); |
| 65 | if (fd < 0) { |
| 66 | BOOST_THROW_EXCEPTION(Error("Cannot create netlink socket ("s + std::strerror(errno) + ")")); |
| 67 | } |
| 68 | m_sock->assign(fd); |
| 69 | |
| 70 | // increase socket receive buffer to 1MB to avoid losing messages |
| 71 | const int bufsize = 1 * 1024 * 1024; |
| 72 | if (::setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &bufsize, sizeof(bufsize)) < 0) { |
| 73 | // not a fatal error |
| 74 | NDN_LOG_DEBUG("setting SO_RCVBUF failed: " << std::strerror(errno)); |
| 75 | } |
| 76 | |
| 77 | // enable control messages for received packets to get the destination group |
| 78 | const int one = 1; |
| 79 | if (::setsockopt(fd, SOL_NETLINK, NETLINK_PKTINFO, &one, sizeof(one)) < 0) { |
| 80 | BOOST_THROW_EXCEPTION(Error("Cannot enable NETLINK_PKTINFO ("s + std::strerror(errno) + ")")); |
| 81 | } |
| 82 | |
| 83 | sockaddr_nl addr{}; |
| 84 | addr.nl_family = AF_NETLINK; |
| 85 | if (::bind(fd, reinterpret_cast<sockaddr*>(&addr), sizeof(addr)) < 0) { |
| 86 | BOOST_THROW_EXCEPTION(Error("Cannot bind netlink socket ("s + std::strerror(errno) + ")")); |
| 87 | } |
| 88 | |
| 89 | // find out what pid has been assigned to us |
| 90 | socklen_t len = sizeof(addr); |
| 91 | if (::getsockname(fd, reinterpret_cast<sockaddr*>(&addr), &len) < 0) { |
| 92 | BOOST_THROW_EXCEPTION(Error("Cannot obtain netlink socket address ("s + std::strerror(errno) + ")")); |
| 93 | } |
| 94 | if (len != sizeof(addr)) { |
| 95 | BOOST_THROW_EXCEPTION(Error("Wrong address length (" + to_string(len) + ")")); |
| 96 | } |
| 97 | if (addr.nl_family != AF_NETLINK) { |
| 98 | BOOST_THROW_EXCEPTION(Error("Wrong address family (" + to_string(addr.nl_family) + ")")); |
| 99 | } |
| 100 | m_pid = addr.nl_pid; |
| 101 | NDN_LOG_TRACE("our pid is " << m_pid); |
| 102 | |
| 103 | #ifdef NDN_CXX_HAVE_NETLINK_EXT_ACK |
| 104 | // enable extended ACK reporting |
| 105 | if (::setsockopt(fd, SOL_NETLINK, NETLINK_EXT_ACK, &one, sizeof(one)) < 0) { |
| 106 | // not a fatal error |
| 107 | NDN_LOG_DEBUG("setting NETLINK_EXT_ACK failed: " << std::strerror(errno)); |
| 108 | } |
| 109 | #endif // NDN_CXX_HAVE_NETLINK_EXT_ACK |
| 110 | } |
| 111 | |
| 112 | void |
| 113 | NetlinkSocket::joinGroup(int group) |
| 114 | { |
| 115 | if (::setsockopt(m_sock->native_handle(), SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, |
| 116 | &group, sizeof(group)) < 0) { |
| 117 | BOOST_THROW_EXCEPTION(Error("Cannot join netlink group " + to_string(group) + |
| 118 | " (" + std::strerror(errno) + ")")); |
| 119 | } |
| 120 | } |
| 121 | |
| 122 | void |
Davide Pesavento | dc5bb96 | 2018-08-12 23:40:38 -0400 | [diff] [blame] | 123 | NetlinkSocket::registerNotificationCallback(MessageCallback cb) |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 124 | { |
Davide Pesavento | dc5bb96 | 2018-08-12 23:40:38 -0400 | [diff] [blame] | 125 | registerRequestCallback(0, std::move(cb)); |
| 126 | } |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 127 | |
Davide Pesavento | dc5bb96 | 2018-08-12 23:40:38 -0400 | [diff] [blame] | 128 | void |
| 129 | NetlinkSocket::registerRequestCallback(uint32_t seq, MessageCallback cb) |
| 130 | { |
| 131 | if (cb == nullptr) { |
| 132 | m_pendingRequests.erase(seq); |
| 133 | } |
| 134 | else { |
| 135 | bool wasEmpty = m_pendingRequests.empty(); |
| 136 | m_pendingRequests.emplace(seq, std::move(cb)); |
| 137 | if (wasEmpty) |
| 138 | asyncWait(); |
| 139 | } |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 140 | } |
| 141 | |
Davide Pesavento | 1077499 | 2018-08-19 18:47:50 -0400 | [diff] [blame^] | 142 | std::string |
| 143 | NetlinkSocket::nlmsgTypeToString(uint16_t type) const |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 144 | { |
Davide Pesavento | 1077499 | 2018-08-19 18:47:50 -0400 | [diff] [blame^] | 145 | #define NLMSG_STRINGIFY(x) case NLMSG_##x: return to_string(type) + "<" #x ">" |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 146 | switch (type) { |
| 147 | NLMSG_STRINGIFY(NOOP); |
| 148 | NLMSG_STRINGIFY(ERROR); |
| 149 | NLMSG_STRINGIFY(DONE); |
| 150 | NLMSG_STRINGIFY(OVERRUN); |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 151 | default: |
Davide Pesavento | 1077499 | 2018-08-19 18:47:50 -0400 | [diff] [blame^] | 152 | return to_string(type); |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 153 | } |
| 154 | #undef NLMSG_STRINGIFY |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 155 | } |
| 156 | |
| 157 | void |
| 158 | NetlinkSocket::asyncWait() |
| 159 | { |
| 160 | m_sock->async_read_some(boost::asio::null_buffers(), |
| 161 | // capture a copy of 'm_sock' to prevent its deallocation while the handler is still pending |
| 162 | [this, sock = m_sock] (const boost::system::error_code& ec, size_t) { |
| 163 | if (!sock->is_open() || ec == boost::asio::error::operation_aborted) { |
| 164 | // socket was closed, ignore the error |
| 165 | NDN_LOG_DEBUG("netlink socket closed or operation aborted"); |
| 166 | } |
| 167 | else if (ec) { |
| 168 | NDN_LOG_ERROR("read failed: " << ec.message()); |
| 169 | BOOST_THROW_EXCEPTION(Error("Netlink socket read error (" + ec.message() + ")")); |
| 170 | } |
| 171 | else { |
| 172 | receiveAndValidate(); |
Davide Pesavento | dc5bb96 | 2018-08-12 23:40:38 -0400 | [diff] [blame] | 173 | if (!m_pendingRequests.empty()) |
| 174 | asyncWait(); |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 175 | } |
| 176 | }); |
| 177 | } |
| 178 | |
| 179 | void |
| 180 | NetlinkSocket::receiveAndValidate() |
| 181 | { |
| 182 | sockaddr_nl sender{}; |
| 183 | iovec iov{}; |
| 184 | iov.iov_base = m_buffer.data(); |
| 185 | iov.iov_len = m_buffer.size(); |
| 186 | uint8_t cmsgBuffer[CMSG_SPACE(sizeof(nl_pktinfo))]; |
| 187 | msghdr msg{}; |
| 188 | msg.msg_name = &sender; |
| 189 | msg.msg_namelen = sizeof(sender); |
| 190 | msg.msg_iov = &iov; |
| 191 | msg.msg_iovlen = 1; |
| 192 | msg.msg_control = cmsgBuffer; |
| 193 | msg.msg_controllen = sizeof(cmsgBuffer); |
| 194 | |
| 195 | ssize_t nBytesRead = ::recvmsg(m_sock->native_handle(), &msg, 0); |
| 196 | if (nBytesRead < 0) { |
| 197 | std::string errorString = std::strerror(errno); |
| 198 | if (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK) { |
| 199 | // not a fatal error |
| 200 | NDN_LOG_DEBUG("recvmsg failed: " << errorString); |
| 201 | return; |
| 202 | } |
| 203 | NDN_LOG_ERROR("recvmsg failed: " << errorString); |
| 204 | BOOST_THROW_EXCEPTION(Error("Netlink socket receive error (" + errorString + ")")); |
| 205 | } |
| 206 | |
| 207 | NDN_LOG_TRACE("read " << nBytesRead << " bytes from netlink socket"); |
| 208 | |
| 209 | if (msg.msg_flags & MSG_TRUNC) { |
| 210 | NDN_LOG_ERROR("truncated message"); |
| 211 | BOOST_THROW_EXCEPTION(Error("Received truncated netlink message")); |
| 212 | // TODO: grow the buffer and start over |
| 213 | } |
| 214 | |
| 215 | if (msg.msg_namelen >= sizeof(sender) && sender.nl_pid != 0) { |
| 216 | NDN_LOG_TRACE("ignoring message from pid=" << sender.nl_pid); |
| 217 | return; |
| 218 | } |
| 219 | |
| 220 | uint32_t nlGroup = 0; |
| 221 | for (cmsghdr* cmsg = CMSG_FIRSTHDR(&msg); cmsg != nullptr; cmsg = CMSG_NXTHDR(&msg, cmsg)) { |
| 222 | if (cmsg->cmsg_level == SOL_NETLINK && |
| 223 | cmsg->cmsg_type == NETLINK_PKTINFO && |
| 224 | cmsg->cmsg_len == CMSG_LEN(sizeof(nl_pktinfo))) { |
| 225 | const nl_pktinfo* pktinfo = reinterpret_cast<nl_pktinfo*>(CMSG_DATA(cmsg)); |
| 226 | nlGroup = pktinfo->group; |
| 227 | } |
| 228 | } |
| 229 | |
| 230 | NetlinkMessage nlmsg(m_buffer.data(), static_cast<size_t>(nBytesRead)); |
| 231 | for (; nlmsg.isValid(); nlmsg = nlmsg.getNext()) { |
| 232 | NDN_LOG_TRACE("parsing " << (nlmsg->nlmsg_flags & NLM_F_MULTI ? "multi-part " : "") << |
Davide Pesavento | 1077499 | 2018-08-19 18:47:50 -0400 | [diff] [blame^] | 233 | "message type=" << nlmsgTypeToString(nlmsg->nlmsg_type) << |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 234 | " len=" << nlmsg->nlmsg_len << |
| 235 | " seq=" << nlmsg->nlmsg_seq << |
| 236 | " pid=" << nlmsg->nlmsg_pid << |
| 237 | " group=" << nlGroup); |
| 238 | |
Davide Pesavento | dc5bb96 | 2018-08-12 23:40:38 -0400 | [diff] [blame] | 239 | auto cbIt = m_pendingRequests.end(); |
| 240 | if (nlGroup != 0) { |
| 241 | // it's a multicast notification |
| 242 | cbIt = m_pendingRequests.find(0); |
| 243 | } |
| 244 | else if (nlmsg->nlmsg_pid == m_pid) { |
| 245 | // it's for us |
| 246 | cbIt = m_pendingRequests.find(nlmsg->nlmsg_seq); |
| 247 | } |
| 248 | else { |
| 249 | NDN_LOG_TRACE("pid mismatch, ignoring"); |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 250 | continue; |
| 251 | } |
| 252 | |
Davide Pesavento | dc5bb96 | 2018-08-12 23:40:38 -0400 | [diff] [blame] | 253 | if (cbIt == m_pendingRequests.end()) { |
| 254 | NDN_LOG_TRACE("no handler registered, ignoring"); |
| 255 | continue; |
| 256 | } |
| 257 | else if (nlmsg->nlmsg_flags & NLM_F_DUMP_INTR) { |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 258 | NDN_LOG_ERROR("dump is inconsistent"); |
| 259 | BOOST_THROW_EXCEPTION(Error("Inconsistency detected in netlink dump")); |
| 260 | // TODO: discard the rest of the message and retry the dump |
| 261 | } |
Davide Pesavento | dc5bb96 | 2018-08-12 23:40:38 -0400 | [diff] [blame] | 262 | else { |
| 263 | // invoke the callback |
| 264 | BOOST_ASSERT(cbIt->second); |
| 265 | cbIt->second(nlmsg); |
| 266 | } |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 267 | |
Davide Pesavento | dc5bb96 | 2018-08-12 23:40:38 -0400 | [diff] [blame] | 268 | // garbage collect the handler if we don't need it anymore: |
| 269 | // do it only if this is a reply message (i.e. not a notification) and either |
| 270 | // (1) it's not a multi-part message, in which case this is the only fragment, or |
| 271 | // (2) it's the last fragment of a multi-part message |
| 272 | if (nlGroup == 0 && (!(nlmsg->nlmsg_flags & NLM_F_MULTI) || nlmsg->nlmsg_type == NLMSG_DONE)) { |
| 273 | NDN_LOG_TRACE("removing handler for seq=" << nlmsg->nlmsg_seq); |
| 274 | BOOST_ASSERT(cbIt != m_pendingRequests.end()); |
| 275 | m_pendingRequests.erase(cbIt); |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 276 | } |
| 277 | } |
| 278 | } |
| 279 | |
| 280 | RtnlSocket::RtnlSocket(boost::asio::io_service& io) |
| 281 | : NetlinkSocket(io) |
| 282 | { |
| 283 | } |
| 284 | |
| 285 | void |
| 286 | RtnlSocket::open() |
| 287 | { |
| 288 | NDN_LOG_TRACE("opening rtnetlink socket"); |
| 289 | NetlinkSocket::open(NETLINK_ROUTE); |
| 290 | } |
| 291 | |
| 292 | void |
Davide Pesavento | dc5bb96 | 2018-08-12 23:40:38 -0400 | [diff] [blame] | 293 | RtnlSocket::sendDumpRequest(uint16_t nlmsgType, MessageCallback cb) |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 294 | { |
| 295 | struct RtnlRequest |
| 296 | { |
| 297 | nlmsghdr nlh; |
| 298 | alignas(NLMSG_ALIGNTO) ifinfomsg ifi; |
| 299 | alignas(NLMSG_ALIGNTO) rtattr rta; |
| 300 | alignas(NLMSG_ALIGNTO) uint32_t rtext; // space for IFLA_EXT_MASK |
| 301 | }; |
| 302 | |
| 303 | auto request = make_shared<RtnlRequest>(); |
| 304 | request->nlh.nlmsg_type = nlmsgType; |
| 305 | request->nlh.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP; |
| 306 | request->nlh.nlmsg_seq = ++m_seqNum; |
| 307 | request->nlh.nlmsg_pid = m_pid; |
| 308 | request->ifi.ifi_family = AF_UNSPEC; |
| 309 | request->rta.rta_type = IFLA_EXT_MASK; |
| 310 | request->rta.rta_len = RTA_LENGTH(sizeof(request->rtext)); |
| 311 | request->rtext = RTEXT_FILTER_SKIP_STATS; |
| 312 | request->nlh.nlmsg_len = NLMSG_SPACE(sizeof(ifinfomsg)) + request->rta.rta_len; |
| 313 | |
Davide Pesavento | dc5bb96 | 2018-08-12 23:40:38 -0400 | [diff] [blame] | 314 | registerRequestCallback(request->nlh.nlmsg_seq, std::move(cb)); |
| 315 | |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 316 | boost::asio::async_write(*m_sock, boost::asio::buffer(request.get(), request->nlh.nlmsg_len), |
| 317 | // capture 'request' to prevent its premature deallocation |
Davide Pesavento | 1077499 | 2018-08-19 18:47:50 -0400 | [diff] [blame^] | 318 | [this, request] (const boost::system::error_code& ec, size_t) { |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 319 | if (!ec) { |
Davide Pesavento | 1077499 | 2018-08-19 18:47:50 -0400 | [diff] [blame^] | 320 | NDN_LOG_TRACE("sent dump request type=" << nlmsgTypeToString(request->nlh.nlmsg_type) |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 321 | << " seq=" << request->nlh.nlmsg_seq); |
| 322 | } |
| 323 | else if (ec != boost::asio::error::operation_aborted) { |
| 324 | NDN_LOG_ERROR("write failed: " << ec.message()); |
| 325 | BOOST_THROW_EXCEPTION(Error("Failed to send netlink request (" + ec.message() + ")")); |
| 326 | } |
| 327 | }); |
| 328 | } |
| 329 | |
Davide Pesavento | 1077499 | 2018-08-19 18:47:50 -0400 | [diff] [blame^] | 330 | std::string |
| 331 | RtnlSocket::nlmsgTypeToString(uint16_t type) const |
| 332 | { |
| 333 | #define RTM_STRINGIFY(x) case RTM_##x: return to_string(type) + "<" #x ">" |
| 334 | switch (type) { |
| 335 | RTM_STRINGIFY(NEWLINK); |
| 336 | RTM_STRINGIFY(DELLINK); |
| 337 | RTM_STRINGIFY(GETLINK); |
| 338 | RTM_STRINGIFY(NEWADDR); |
| 339 | RTM_STRINGIFY(DELADDR); |
| 340 | RTM_STRINGIFY(GETADDR); |
| 341 | RTM_STRINGIFY(NEWROUTE); |
| 342 | RTM_STRINGIFY(DELROUTE); |
| 343 | RTM_STRINGIFY(GETROUTE); |
| 344 | default: |
| 345 | return NetlinkSocket::nlmsgTypeToString(type); |
| 346 | } |
| 347 | #undef RTM_STRINGIFY |
| 348 | } |
| 349 | |
| 350 | GenlSocket::GenlSocket(boost::asio::io_service& io) |
| 351 | : NetlinkSocket(io) |
| 352 | { |
| 353 | m_cachedFamilyIds["nlctrl"] = GENL_ID_CTRL; |
| 354 | } |
| 355 | |
| 356 | void |
| 357 | GenlSocket::open() |
| 358 | { |
| 359 | NDN_LOG_TRACE("opening genetlink socket"); |
| 360 | NetlinkSocket::open(NETLINK_GENERIC); |
| 361 | } |
| 362 | |
| 363 | void |
| 364 | GenlSocket::sendRequest(const std::string& familyName, uint8_t command, |
| 365 | const void* payload, size_t payloadLen, |
| 366 | MessageCallback messageCb, std::function<void()> errorCb) |
| 367 | { |
| 368 | auto it = m_cachedFamilyIds.find(familyName); |
| 369 | if (it != m_cachedFamilyIds.end()) { |
| 370 | if (it->second >= GENL_MIN_ID) { |
| 371 | sendRequest(it->second, command, payload, payloadLen, std::move(messageCb)); |
| 372 | } |
| 373 | else if (errorCb) { |
| 374 | errorCb(); |
| 375 | } |
| 376 | return; |
| 377 | } |
| 378 | |
| 379 | auto ret = m_familyResolvers.emplace(std::piecewise_construct, |
| 380 | std::forward_as_tuple(familyName), |
| 381 | std::forward_as_tuple(familyName, *this)); |
| 382 | auto& resolver = ret.first->second; |
| 383 | if (ret.second) { |
| 384 | // cache the result |
| 385 | resolver.onResolved.connectSingleShot([=] (uint16_t familyId) { |
| 386 | m_cachedFamilyIds[familyName] = familyId; |
| 387 | }); |
| 388 | resolver.onError.connectSingleShot([=] { |
| 389 | m_cachedFamilyIds[familyName] = 0; |
| 390 | }); |
| 391 | } |
| 392 | resolver.onResolved.connectSingleShot([=, cb = std::move(messageCb)] (uint16_t familyId) { |
| 393 | sendRequest(familyId, command, payload, payloadLen, std::move(cb)); |
| 394 | }); |
| 395 | if (errorCb) { |
| 396 | resolver.onError.connectSingleShot(std::move(errorCb)); |
| 397 | } |
| 398 | } |
| 399 | |
| 400 | void |
| 401 | GenlSocket::sendRequest(uint16_t familyId, uint8_t command, |
| 402 | const void* payload, size_t payloadLen, MessageCallback cb) |
| 403 | { |
| 404 | struct GenlRequestHeader |
| 405 | { |
| 406 | alignas(NLMSG_ALIGNTO) nlmsghdr nlh; |
| 407 | alignas(NLMSG_ALIGNTO) genlmsghdr genlh; |
| 408 | }; |
| 409 | static_assert(sizeof(GenlRequestHeader) == NLMSG_SPACE(GENL_HDRLEN), ""); |
| 410 | |
| 411 | auto hdr = make_shared<GenlRequestHeader>(); |
| 412 | hdr->nlh.nlmsg_len = sizeof(GenlRequestHeader) + payloadLen; |
| 413 | hdr->nlh.nlmsg_type = familyId; |
| 414 | hdr->nlh.nlmsg_flags = NLM_F_REQUEST; |
| 415 | hdr->nlh.nlmsg_seq = ++m_seqNum; |
| 416 | hdr->nlh.nlmsg_pid = m_pid; |
| 417 | hdr->genlh.cmd = command; |
| 418 | hdr->genlh.version = 1; |
| 419 | |
| 420 | registerRequestCallback(hdr->nlh.nlmsg_seq, std::move(cb)); |
| 421 | |
| 422 | std::array<boost::asio::const_buffer, 2> bufs = { |
| 423 | boost::asio::buffer(hdr.get(), sizeof(GenlRequestHeader)), |
| 424 | boost::asio::buffer(payload, payloadLen) |
| 425 | }; |
| 426 | boost::asio::async_write(*m_sock, bufs, |
| 427 | // capture 'hdr' to prevent its premature deallocation |
| 428 | [this, hdr] (const boost::system::error_code& ec, size_t) { |
| 429 | if (!ec) { |
| 430 | NDN_LOG_TRACE("sent genl request type=" << nlmsgTypeToString(hdr->nlh.nlmsg_type) << |
| 431 | " cmd=" << static_cast<unsigned>(hdr->genlh.cmd) << |
| 432 | " seq=" << hdr->nlh.nlmsg_seq); |
| 433 | } |
| 434 | else if (ec != boost::asio::error::operation_aborted) { |
| 435 | NDN_LOG_ERROR("write failed: " << ec.message()); |
| 436 | BOOST_THROW_EXCEPTION(Error("Failed to send netlink request (" + ec.message() + ")")); |
| 437 | } |
| 438 | }); |
| 439 | } |
| 440 | |
| 441 | GenlFamilyResolver::GenlFamilyResolver(std::string familyName, GenlSocket& socket) |
| 442 | : m_sock(socket) |
| 443 | , m_family(std::move(familyName)) |
| 444 | { |
| 445 | if (m_family.size() >= GENL_NAMSIZ) { |
| 446 | BOOST_THROW_EXCEPTION(std::invalid_argument("netlink family name '" + m_family + "' too long")); |
| 447 | } |
| 448 | |
| 449 | NDN_LOG_TRACE("resolving netlink family " << m_family); |
| 450 | asyncResolve(); |
| 451 | } |
| 452 | |
| 453 | void |
| 454 | GenlFamilyResolver::asyncResolve() |
| 455 | { |
| 456 | struct FamilyNameAttribute |
| 457 | { |
| 458 | alignas(NLMSG_ALIGNTO) nlattr nla; |
| 459 | alignas(NLMSG_ALIGNTO) char name[GENL_NAMSIZ]; |
| 460 | }; |
| 461 | |
| 462 | auto attr = make_shared<FamilyNameAttribute>(); |
| 463 | attr->nla.nla_type = CTRL_ATTR_FAMILY_NAME; |
| 464 | attr->nla.nla_len = NLA_HDRLEN + m_family.size() + 1; |
| 465 | ::strncpy(attr->name, m_family.data(), GENL_NAMSIZ); |
| 466 | |
| 467 | m_sock.sendRequest(GENL_ID_CTRL, CTRL_CMD_GETFAMILY, attr.get(), attr->nla.nla_len, |
| 468 | // capture 'attr' to prevent its premature deallocation |
| 469 | [this, attr] (const auto& msg) { this->handleResolve(msg); }); |
| 470 | } |
| 471 | |
| 472 | void |
| 473 | GenlFamilyResolver::handleResolve(const NetlinkMessage& nlmsg) |
| 474 | { |
| 475 | switch (nlmsg->nlmsg_type) { |
| 476 | case NLMSG_ERROR: { |
| 477 | const nlmsgerr* err = nlmsg.getPayload<nlmsgerr>(); |
| 478 | if (err == nullptr) { |
| 479 | NDN_LOG_WARN("malformed nlmsgerr"); |
| 480 | } |
| 481 | else if (err->error != 0) { |
| 482 | NDN_LOG_DEBUG("failed to resolve netlink family " << m_family << ": " |
| 483 | << std::strerror(std::abs(err->error))); |
| 484 | } |
| 485 | onError(); |
| 486 | break; |
| 487 | } |
| 488 | |
| 489 | case GENL_ID_CTRL: { |
| 490 | const genlmsghdr* genlh = nlmsg.getPayload<genlmsghdr>(); |
| 491 | if (genlh == nullptr) { |
| 492 | NDN_LOG_WARN("malformed genlmsghdr"); |
| 493 | return onError(); |
| 494 | } |
| 495 | if (genlh->cmd != CTRL_CMD_NEWFAMILY) { |
| 496 | NDN_LOG_WARN("unexpected genl cmd=" << static_cast<unsigned>(genlh->cmd)); |
| 497 | return onError(); |
| 498 | } |
| 499 | |
| 500 | auto attrs = nlmsg.getAttributes<nlattr>(genlh); |
| 501 | auto familyName = attrs.getAttributeByType<std::string>(CTRL_ATTR_FAMILY_NAME); |
| 502 | if (familyName && *familyName != m_family) { |
| 503 | NDN_LOG_WARN("CTRL_ATTR_FAMILY_NAME mismatch: " << *familyName << " != " << m_family); |
| 504 | return onError(); |
| 505 | } |
| 506 | auto familyId = attrs.getAttributeByType<uint16_t>(CTRL_ATTR_FAMILY_ID); |
| 507 | if (!familyId) { |
| 508 | NDN_LOG_WARN("missing CTRL_ATTR_FAMILY_ID"); |
| 509 | return onError(); |
| 510 | } |
| 511 | if (*familyId < GENL_MIN_ID) { |
| 512 | NDN_LOG_WARN("invalid CTRL_ATTR_FAMILY_ID=" << *familyId); |
| 513 | return onError(); |
| 514 | } |
| 515 | |
| 516 | NDN_LOG_TRACE("resolved netlink family name=" << m_family << " id=" << *familyId); |
| 517 | onResolved(*familyId); |
| 518 | break; |
| 519 | } |
| 520 | |
| 521 | default: { |
| 522 | NDN_LOG_WARN("unexpected message type"); |
| 523 | onError(); |
| 524 | break; |
| 525 | } |
| 526 | } |
| 527 | } |
| 528 | |
| 529 | std::string |
| 530 | GenlSocket::nlmsgTypeToString(uint16_t type) const |
| 531 | { |
| 532 | if (type >= GENL_MIN_ID) { |
| 533 | for (const auto& p : m_cachedFamilyIds) { |
| 534 | if (p.second == type) { |
| 535 | return to_string(type) + "<" + p.first + ">"; |
| 536 | } |
| 537 | } |
| 538 | } |
| 539 | |
| 540 | return NetlinkSocket::nlmsgTypeToString(type); |
| 541 | } |
| 542 | |
Davide Pesavento | a0b2a2c | 2018-07-19 01:01:06 -0400 | [diff] [blame] | 543 | } // namespace net |
| 544 | } // namespace ndn |