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-rw-r--r--runtime/jdwp/jdwp_socket.cc502
1 files changed, 502 insertions, 0 deletions
diff --git a/runtime/jdwp/jdwp_socket.cc b/runtime/jdwp/jdwp_socket.cc
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+++ b/runtime/jdwp/jdwp_socket.cc
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+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <arpa/inet.h>
+#include <errno.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "base/logging.h"
+#include "base/stringprintf.h"
+#include "jdwp/jdwp_priv.h"
+
+#define kBasePort 8000
+#define kMaxPort 8040
+
+namespace art {
+
+namespace JDWP {
+
+/*
+ * JDWP network state.
+ *
+ * We only talk to one debugger at a time.
+ */
+struct JdwpSocketState : public JdwpNetStateBase {
+ uint16_t listenPort;
+ int listenSock; /* listen for connection from debugger */
+
+ JdwpSocketState(JdwpState* state) : JdwpNetStateBase(state) {
+ listenPort = 0;
+ listenSock = -1;
+ }
+
+ virtual bool Accept();
+ virtual bool Establish(const JdwpOptions*);
+ virtual void Shutdown();
+ virtual bool ProcessIncoming();
+
+ private:
+ in_addr remote_addr_;
+ uint16_t remote_port_;
+};
+
+static JdwpSocketState* SocketStartup(JdwpState* state, uint16_t port, bool probe);
+
+/*
+ * Set up some stuff for transport=dt_socket.
+ */
+bool InitSocketTransport(JdwpState* state, const JdwpOptions* options) {
+ uint16_t port = options->port;
+
+ if (options->server) {
+ if (options->port != 0) {
+ /* try only the specified port */
+ state->netState = SocketStartup(state, port, false);
+ } else {
+ /* scan through a range of ports, binding to the first available */
+ for (port = kBasePort; port <= kMaxPort; port++) {
+ state->netState = SocketStartup(state, port, true);
+ if (state->netState != NULL) {
+ break;
+ }
+ }
+ }
+ if (state->netState == NULL) {
+ LOG(ERROR) << "JDWP net startup failed (req port=" << options->port << ")";
+ return false;
+ }
+ } else {
+ state->netState = SocketStartup(state, 0, false);
+ }
+
+ if (options->suspend) {
+ LOG(INFO) << "JDWP will wait for debugger on port " << port;
+ } else {
+ LOG(INFO) << "JDWP will " << (options->server ? "listen" : "connect") << " on port " << port;
+ }
+
+ return true;
+}
+
+/*
+ * Initialize JDWP stuff.
+ *
+ * Allocates a new state structure. If "port" is non-zero, this also
+ * tries to bind to a listen port. If "port" is zero, we assume
+ * we're preparing for an outbound connection, and return without binding
+ * to anything.
+ *
+ * This may be called several times if we're probing for a port.
+ *
+ * Returns 0 on success.
+ */
+static JdwpSocketState* SocketStartup(JdwpState* state, uint16_t port, bool probe) {
+ JdwpSocketState* netState = new JdwpSocketState(state);
+ if (port == 0) {
+ return netState;
+ }
+
+ netState->listenSock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
+ if (netState->listenSock < 0) {
+ PLOG(probe ? ERROR : FATAL) << "Socket create failed";
+ goto fail;
+ }
+
+ /* allow immediate re-use */
+ {
+ int one = 1;
+ if (setsockopt(netState->listenSock, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)) < 0) {
+ PLOG(probe ? ERROR : FATAL) << "setsockopt(SO_REUSEADDR) failed";
+ goto fail;
+ }
+ }
+
+ union {
+ sockaddr_in addrInet;
+ sockaddr addrPlain;
+ } addr;
+ addr.addrInet.sin_family = AF_INET;
+ addr.addrInet.sin_port = htons(port);
+ inet_aton("127.0.0.1", &addr.addrInet.sin_addr);
+
+ if (bind(netState->listenSock, &addr.addrPlain, sizeof(addr)) != 0) {
+ PLOG(probe ? ERROR : FATAL) << "Attempt to bind to port " << port << " failed";
+ goto fail;
+ }
+
+ netState->listenPort = port;
+
+ if (listen(netState->listenSock, 5) != 0) {
+ PLOG(probe ? ERROR : FATAL) << "Listen failed";
+ goto fail;
+ }
+
+ return netState;
+
+ fail:
+ netState->Shutdown();
+ delete netState;
+ return NULL;
+}
+
+/*
+ * Shut down JDWP listener. Don't free state.
+ *
+ * This may be called from a non-JDWP thread as part of shutting the
+ * JDWP thread down.
+ *
+ * (This is currently called several times during startup as we probe
+ * for an open port.)
+ */
+void JdwpSocketState::Shutdown() {
+ int listenSock = this->listenSock;
+ int clientSock = this->clientSock;
+
+ /* clear these out so it doesn't wake up and try to reuse them */
+ this->listenSock = this->clientSock = -1;
+
+ /* "shutdown" dislodges blocking read() and accept() calls */
+ if (listenSock != -1) {
+ shutdown(listenSock, SHUT_RDWR);
+ close(listenSock);
+ }
+ if (clientSock != -1) {
+ shutdown(clientSock, SHUT_RDWR);
+ close(clientSock);
+ }
+
+ WakePipe();
+}
+
+/*
+ * Disable the TCP Nagle algorithm, which delays transmission of outbound
+ * packets until the previous transmissions have been acked. JDWP does a
+ * lot of back-and-forth with small packets, so this may help.
+ */
+static int SetNoDelay(int fd) {
+ int on = 1;
+ int cc = setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &on, sizeof(on));
+ CHECK_EQ(cc, 0);
+ return cc;
+}
+
+/*
+ * Accept a connection. This will block waiting for somebody to show up.
+ * If that's not desirable, use checkConnection() to make sure something
+ * is pending.
+ */
+bool JdwpSocketState::Accept() {
+ union {
+ sockaddr_in addrInet;
+ sockaddr addrPlain;
+ } addr;
+ socklen_t addrlen;
+ int sock;
+
+ if (listenSock < 0) {
+ return false; /* you're not listening! */
+ }
+
+ CHECK(clientSock == -1); /* must not already be talking */
+
+ addrlen = sizeof(addr);
+ do {
+ sock = accept(listenSock, &addr.addrPlain, &addrlen);
+ if (sock < 0 && errno != EINTR) {
+ // When we call shutdown() on the socket, accept() returns with
+ // EINVAL. Don't gripe about it.
+ if (errno == EINVAL) {
+ if (VLOG_IS_ON(jdwp)) {
+ PLOG(ERROR) << "accept failed";
+ }
+ } else {
+ PLOG(ERROR) << "accept failed";
+ return false;
+ }
+ }
+ } while (sock < 0);
+
+ remote_addr_ = addr.addrInet.sin_addr;
+ remote_port_ = ntohs(addr.addrInet.sin_port);
+ VLOG(jdwp) << "+++ accepted connection from " << inet_ntoa(remote_addr_) << ":" << remote_port_;
+
+ clientSock = sock;
+ SetAwaitingHandshake(true);
+ input_count_ = 0;
+
+ VLOG(jdwp) << "Setting TCP_NODELAY on accepted socket";
+ SetNoDelay(clientSock);
+
+ if (!MakePipe()) {
+ return false;
+ }
+
+ return true;
+}
+
+/*
+ * Create a connection to a waiting debugger.
+ */
+bool JdwpSocketState::Establish(const JdwpOptions* options) {
+ union {
+ sockaddr_in addrInet;
+ sockaddr addrPlain;
+ } addr;
+ hostent* pEntry;
+
+ CHECK(!options->server);
+ CHECK(!options->host.empty());
+ CHECK_NE(options->port, 0);
+
+ /*
+ * Start by resolving the host name.
+ */
+#ifdef HAVE_GETHOSTBYNAME_R
+ hostent he;
+ char auxBuf[128];
+ int error;
+ int cc = gethostbyname_r(options->host.c_str(), &he, auxBuf, sizeof(auxBuf), &pEntry, &error);
+ if (cc != 0) {
+ LOG(WARNING) << "gethostbyname_r('" << options->host << "') failed: " << hstrerror(error);
+ return false;
+ }
+#else
+ h_errno = 0;
+ pEntry = gethostbyname(options->host.c_str());
+ if (pEntry == NULL) {
+ PLOG(WARNING) << "gethostbyname('" << options->host << "') failed";
+ return false;
+ }
+#endif
+
+ /* copy it out ASAP to minimize risk of multithreaded annoyances */
+ memcpy(&addr.addrInet.sin_addr, pEntry->h_addr, pEntry->h_length);
+ addr.addrInet.sin_family = pEntry->h_addrtype;
+
+ addr.addrInet.sin_port = htons(options->port);
+
+ LOG(INFO) << "Connecting out to " << inet_ntoa(addr.addrInet.sin_addr) << ":" << ntohs(addr.addrInet.sin_port);
+
+ /*
+ * Create a socket.
+ */
+ clientSock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
+ if (clientSock < 0) {
+ PLOG(ERROR) << "Unable to create socket";
+ return false;
+ }
+
+ /*
+ * Try to connect.
+ */
+ if (connect(clientSock, &addr.addrPlain, sizeof(addr)) != 0) {
+ PLOG(ERROR) << "Unable to connect to " << inet_ntoa(addr.addrInet.sin_addr) << ":" << ntohs(addr.addrInet.sin_port);
+ close(clientSock);
+ clientSock = -1;
+ return false;
+ }
+
+ LOG(INFO) << "Connection established to " << options->host << " (" << inet_ntoa(addr.addrInet.sin_addr) << ":" << ntohs(addr.addrInet.sin_port) << ")";
+ SetAwaitingHandshake(true);
+ input_count_ = 0;
+
+ SetNoDelay(clientSock);
+
+ if (!MakePipe()) {
+ return false;
+ }
+
+ return true;
+}
+
+/*
+ * Process incoming data. If no data is available, this will block until
+ * some arrives.
+ *
+ * If we get a full packet, handle it.
+ *
+ * To take some of the mystery out of life, we want to reject incoming
+ * connections if we already have a debugger attached. If we don't, the
+ * debugger will just mysteriously hang until it times out. We could just
+ * close the listen socket, but there's a good chance we won't be able to
+ * bind to the same port again, which would confuse utilities.
+ *
+ * Returns "false" on error (indicating that the connection has been severed),
+ * "true" if things are still okay.
+ */
+bool JdwpSocketState::ProcessIncoming() {
+ int readCount;
+
+ CHECK(clientSock != -1);
+
+ if (!HaveFullPacket()) {
+ /* read some more, looping until we have data */
+ errno = 0;
+ while (1) {
+ int selCount;
+ fd_set readfds;
+ int maxfd = -1;
+ int fd;
+
+ FD_ZERO(&readfds);
+
+ /* configure fds; note these may get zapped by another thread */
+ fd = listenSock;
+ if (fd >= 0) {
+ FD_SET(fd, &readfds);
+ if (maxfd < fd) {
+ maxfd = fd;
+ }
+ }
+ fd = clientSock;
+ if (fd >= 0) {
+ FD_SET(fd, &readfds);
+ if (maxfd < fd) {
+ maxfd = fd;
+ }
+ }
+ fd = wake_pipe_[0];
+ if (fd >= 0) {
+ FD_SET(fd, &readfds);
+ if (maxfd < fd) {
+ maxfd = fd;
+ }
+ } else {
+ LOG(INFO) << "NOTE: entering select w/o wakepipe";
+ }
+
+ if (maxfd < 0) {
+ VLOG(jdwp) << "+++ all fds are closed";
+ return false;
+ }
+
+ /*
+ * Select blocks until it sees activity on the file descriptors.
+ * Closing the local file descriptor does not count as activity,
+ * so we can't rely on that to wake us up (it works for read()
+ * and accept(), but not select()).
+ *
+ * We can do one of three things: (1) send a signal and catch
+ * EINTR, (2) open an additional fd ("wake pipe") and write to
+ * it when it's time to exit, or (3) time out periodically and
+ * re-issue the select. We're currently using #2, as it's more
+ * reliable than #1 and generally better than #3. Wastes two fds.
+ */
+ selCount = select(maxfd+1, &readfds, NULL, NULL, NULL);
+ if (selCount < 0) {
+ if (errno == EINTR) {
+ continue;
+ }
+ PLOG(ERROR) << "select failed";
+ goto fail;
+ }
+
+ if (wake_pipe_[0] >= 0 && FD_ISSET(wake_pipe_[0], &readfds)) {
+ if (listenSock >= 0) {
+ LOG(ERROR) << "Exit wake set, but not exiting?";
+ } else {
+ LOG(DEBUG) << "Got wake-up signal, bailing out of select";
+ }
+ goto fail;
+ }
+ if (listenSock >= 0 && FD_ISSET(listenSock, &readfds)) {
+ LOG(INFO) << "Ignoring second debugger -- accepting and dropping";
+ union {
+ sockaddr_in addrInet;
+ sockaddr addrPlain;
+ } addr;
+ socklen_t addrlen;
+ int tmpSock;
+ tmpSock = accept(listenSock, &addr.addrPlain, &addrlen);
+ if (tmpSock < 0) {
+ LOG(INFO) << "Weird -- accept failed";
+ } else {
+ close(tmpSock);
+ }
+ }
+ if (clientSock >= 0 && FD_ISSET(clientSock, &readfds)) {
+ readCount = read(clientSock, input_buffer_ + input_count_, sizeof(input_buffer_) - input_count_);
+ if (readCount < 0) {
+ /* read failed */
+ if (errno != EINTR) {
+ goto fail;
+ }
+ LOG(DEBUG) << "+++ EINTR hit";
+ return true;
+ } else if (readCount == 0) {
+ /* EOF hit -- far end went away */
+ VLOG(jdwp) << "+++ peer disconnected";
+ goto fail;
+ } else {
+ break;
+ }
+ }
+ }
+
+ input_count_ += readCount;
+ if (!HaveFullPacket()) {
+ return true; /* still not there yet */
+ }
+ }
+
+ /*
+ * Special-case the initial handshake. For some bizarre reason we're
+ * expected to emulate bad tty settings by echoing the request back
+ * exactly as it was sent. Note the handshake is always initiated by
+ * the debugger, no matter who connects to whom.
+ *
+ * Other than this one case, the protocol [claims to be] stateless.
+ */
+ if (IsAwaitingHandshake()) {
+ if (memcmp(input_buffer_, kMagicHandshake, kMagicHandshakeLen) != 0) {
+ LOG(ERROR) << StringPrintf("ERROR: bad handshake '%.14s'", input_buffer_);
+ goto fail;
+ }
+
+ errno = 0;
+ int cc = TEMP_FAILURE_RETRY(write(clientSock, input_buffer_, kMagicHandshakeLen));
+ if (cc != kMagicHandshakeLen) {
+ PLOG(ERROR) << "Failed writing handshake bytes (" << cc << " of " << kMagicHandshakeLen << ")";
+ goto fail;
+ }
+
+ ConsumeBytes(kMagicHandshakeLen);
+ SetAwaitingHandshake(false);
+ VLOG(jdwp) << "+++ handshake complete";
+ return true;
+ }
+
+ /*
+ * Handle this packet.
+ */
+ return state_->HandlePacket();
+
+ fail:
+ Close();
+ return false;
+}
+
+} // namespace JDWP
+
+} // namespace art
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