/*
- * DEBUG: section 05 Socket Connection Opener
+ * Copyright (C) 1996-2021 The Squid Software Foundation and contributors
+ *
+ * Squid software is distributed under GPLv2+ license and includes
+ * contributions from numerous individuals and organizations.
+ * Please see the COPYING and CONTRIBUTORS files for details.
*/
+/* DEBUG: section 05 Socket Connection Opener */
+
#include "squid.h"
-#include "comm/ConnOpener.h"
+#include "CachePeer.h"
+#include "comm.h"
#include "comm/Connection.h"
+#include "comm/ConnOpener.h"
#include "comm/Loops.h"
-#include "comm.h"
+#include "fd.h"
#include "fde.h"
+#include "globals.h"
#include "icmp/net_db.h"
+#include "ip/QosConfig.h"
+#include "ip/tools.h"
#include "ipcache.h"
+#include "SquidConfig.h"
#include "SquidTime.h"
-namespace Comm
+#include <cerrno>
+
+class CachePeer;
+
+CBDATA_NAMESPACED_CLASS_INIT(Comm, ConnOpener);
+
+Comm::ConnOpener::ConnOpener(const Comm::ConnectionPointer &c, const AsyncCall::Pointer &handler, time_t ctimeout) :
+ AsyncJob("Comm::ConnOpener"),
+ host_(NULL),
+ temporaryFd_(-1),
+ conn_(c),
+ callback_(handler),
+ totalTries_(0),
+ failRetries_(0),
+ deadline_(squid_curtime + static_cast<time_t>(ctimeout))
{
-CBDATA_CLASS_INIT(ConnOpener);
-};
-
-Comm::ConnOpener::ConnOpener(Comm::ConnectionPointer &c, AsyncCall::Pointer &handler, time_t ctimeout) :
- AsyncJob("Comm::ConnOpener"),
- host_(NULL),
- temporaryFd_(-1),
- conn_(c),
- callback_(handler),
- totalTries_(0),
- failRetries_(0),
- connectTimeout_(ctimeout),
- connectStart_(0)
-{}
+ debugs(5, 3, "will connect to " << c << " with " << ctimeout << " timeout");
+}
Comm::ConnOpener::~ConnOpener()
{
return AsyncJob::doneAll();
}
+ // otherwise, we must be waiting for something
+ Must(temporaryFd_ >= 0 || calls_.sleep_);
return false;
}
void
Comm::ConnOpener::swanSong()
{
- // cancel any event watchers
- // done here to get the "swanSong" mention in cancel debugging.
- if (calls_.earlyAbort_ != NULL) {
- calls_.earlyAbort_->cancel("Comm::ConnOpener::swanSong");
- calls_.earlyAbort_ = NULL;
- }
- if (calls_.timeout_ != NULL) {
- calls_.timeout_->cancel("Comm::ConnOpener::swanSong");
- calls_.timeout_ = NULL;
- }
-
if (callback_ != NULL) {
- if (callback_->canceled())
- callback_ = NULL;
- else
- // inform the still-waiting caller we are dying
- doneConnecting(COMM_ERR_CONNECT, 0);
+ // inform the still-waiting caller we are dying
+ sendAnswer(Comm::ERR_CONNECT, 0, "Comm::ConnOpener::swanSong");
}
- // rollback what we can from the job state
- if (temporaryFd_ >= 0) {
- // doneConnecting() handles partial FD connection cleanup
- doneConnecting(COMM_ERR_CONNECT, 0);
- }
+ // did we abort with a temporary FD assigned?
+ if (temporaryFd_ >= 0)
+ closeFd();
+
+ // did we abort while waiting between retries?
+ if (calls_.sleep_)
+ cancelSleep();
AsyncJob::swanSong();
}
/**
* Connection attempt are completed. One way or the other.
* Pass the results back to the external handler.
- * NP: on errors the earlyAbort call should be cancelled first with a reason.
*/
void
-Comm::ConnOpener::doneConnecting(comm_err_t status, int xerrno)
+Comm::ConnOpener::sendAnswer(Comm::Flag errFlag, int xerrno, const char *why)
{
// only mark the address good/bad AFTER connect is finished.
if (host_ != NULL) {
- if (xerrno == 0)
+ if (xerrno == 0) // XXX: should not we use errFlag instead?
ipcacheMarkGoodAddr(host_, conn_->remote);
else {
ipcacheMarkBadAddr(host_, conn_->remote);
}
if (callback_ != NULL) {
- typedef CommConnectCbParams Params;
- Params ¶ms = GetCommParams<Params>(callback_);
- params.conn = conn_;
- params.flag = status;
- params.xerrno = xerrno;
- ScheduleCallHere(callback_);
+ // avoid scheduling cancelled callbacks, assuming they are common
+ // enough to make this extra check an optimization
+ if (callback_->canceled()) {
+ debugs(5, 4, conn_ << " not calling canceled " << *callback_ <<
+ " [" << callback_->id << ']' );
+ // TODO save the pconn to the pconnPool ?
+ } else {
+ typedef CommConnectCbParams Params;
+ Params ¶ms = GetCommParams<Params>(callback_);
+ params.conn = conn_;
+ params.flag = errFlag;
+ params.xerrno = xerrno;
+ ScheduleCallHere(callback_);
+ }
callback_ = NULL;
}
- if (temporaryFd_ >= 0) {
- debugs(5, 4, HERE << conn_ << " closing temp FD " << temporaryFd_);
- // it never reached fully open, so cleanup the FD handlers
- // Note that comm_close() sequence does not happen for partially open FD
- Comm::SetSelect(temporaryFd_, COMM_SELECT_WRITE, NULL, NULL, 0);
+ // The job will stop without this call because nil callback_ makes
+ // doneAll() true, but this explicit call creates nicer debugging.
+ mustStop(why);
+}
+
+/// cleans up this job I/O state without closing temporaryFd
+/// required before closing temporaryFd or keeping it in conn_
+/// leaves FD bare so must only be called via closeFd() or keepFd()
+void
+Comm::ConnOpener::cleanFd()
+{
+ debugs(5, 4, HERE << conn_ << " closing temp FD " << temporaryFd_);
+
+ Must(temporaryFd_ >= 0);
+ fde &f = fd_table[temporaryFd_];
+
+ // Our write_handler was set without using Comm::Write API, so we cannot
+ // use a cancellable Pointer-free job callback and simply cancel it here.
+ if (f.write_handler) {
+
+ /* XXX: We are about to remove write_handler, which was responsible
+ * for deleting write_data, so we have to delete write_data
+ * ourselves. Comm currently calls SetSelect handlers synchronously
+ * so if write_handler is set, we know it has not been called yet.
+ * ConnOpener converts that sync call into an async one, but only
+ * after deleting ptr, so that is not a problem.
+ */
+
+ delete static_cast<Pointer*>(f.write_data);
+ f.write_data = NULL;
+ f.write_handler = NULL;
+ }
+ // Comm::DoSelect does not do this when calling and resetting write_handler
+ // (because it expects more writes to come?). We could mimic that
+ // optimization by resetting Comm "Select" state only when the FD is
+ // actually closed.
+ Comm::SetSelect(temporaryFd_, COMM_SELECT_WRITE, NULL, NULL, 0);
+
+ if (calls_.timeout_ != NULL) {
+ calls_.timeout_->cancel("Comm::ConnOpener::cleanFd");
+ calls_.timeout_ = NULL;
+ }
+ // Comm checkTimeouts() and commCloseAllSockets() do not clear .timeout
+ // when calling timeoutHandler (XXX fix them), so we clear unconditionally.
+ f.timeoutHandler = NULL;
+ f.timeout = 0;
+
+ if (calls_.earlyAbort_ != NULL) {
+ comm_remove_close_handler(temporaryFd_, calls_.earlyAbort_);
calls_.earlyAbort_ = NULL;
- if (calls_.timeout_ != NULL) {
- calls_.timeout_->cancel("Comm::ConnOpener::doneConnecting");
- calls_.timeout_ = NULL;
- }
- fd_table[temporaryFd_].timeoutHandler = NULL;
- fd_table[temporaryFd_].timeout = 0;
- close(temporaryFd_);
- fd_close(temporaryFd_);
- temporaryFd_ = -1;
}
+}
- /* ensure cleared local state, we are done. */
- conn_ = NULL;
+/// cleans I/O state and ends I/O for temporaryFd_
+void
+Comm::ConnOpener::closeFd()
+{
+ if (temporaryFd_ < 0)
+ return;
+
+ cleanFd();
+
+ // comm_close() below uses COMMIO_FD_WRITECB(fd)->active() to clear Comm
+ // "Select" state. It will not clear ours. XXX: It should always clear
+ // because a callback may have been active but was called before comm_close
+ // Update: we now do this in cleanFd()
+ // Comm::SetSelect(temporaryFd_, COMM_SELECT_WRITE, NULL, NULL, 0);
+
+ comm_close(temporaryFd_);
+ temporaryFd_ = -1;
+}
+
+/// cleans I/O state and moves temporaryFd_ to the conn_ for long-term use
+void
+Comm::ConnOpener::keepFd()
+{
+ Must(conn_ != NULL);
+ Must(temporaryFd_ >= 0);
+
+ cleanFd();
+
+ conn_->fd = temporaryFd_;
+ temporaryFd_ = -1;
}
void
{
Must(conn_ != NULL);
- /* get a socket open ready for connecting with */
+ /* outbound sockets have no need to be protocol agnostic. */
+ if (!(Ip::EnableIpv6&IPV6_SPECIAL_V4MAPPING) && conn_->remote.isIPv4()) {
+ conn_->local.setIPv4();
+ }
+
+ conn_->noteStart();
+ if (createFd())
+ doConnect();
+}
+
+/// called at the end of Comm::ConnOpener::DelayedConnectRetry event
+void
+Comm::ConnOpener::restart()
+{
+ debugs(5, 5, conn_ << " restarting after sleep");
+ calls_.sleep_ = false;
+
+ if (createFd())
+ doConnect();
+}
+
+/// Create a socket for the future connection or return false.
+/// If false is returned, done() is guaranteed to return true and end the job.
+bool
+Comm::ConnOpener::createFd()
+{
+ Must(temporaryFd_ < 0);
+
+ // our initiators signal abort by cancelling their callbacks
+ if (callback_ == NULL || callback_->canceled())
+ return false;
+
+ temporaryFd_ = comm_openex(SOCK_STREAM, IPPROTO_TCP, conn_->local, conn_->flags, host_);
if (temporaryFd_ < 0) {
-#if USE_IPV6
- /* outbound sockets have no need to be protocol agnostic. */
- if (conn_->remote.IsIPv4()) {
- conn_->local.SetIPv4();
- }
-#endif
- temporaryFd_ = comm_openex(SOCK_STREAM, IPPROTO_TCP, conn_->local, conn_->flags, conn_->tos, conn_->nfmark, host_);
- if (temporaryFd_ < 0) {
- doneConnecting(COMM_ERR_CONNECT, 0);
- return;
- }
+ sendAnswer(Comm::ERR_CONNECT, 0, "Comm::ConnOpener::createFd");
+ return false;
}
+ // Set TOS if needed.
+ if (conn_->tos &&
+ Ip::Qos::setSockTos(temporaryFd_, conn_->tos, conn_->remote.isIPv4() ? AF_INET : AF_INET6) < 0)
+ conn_->tos = 0;
+#if SO_MARK
+ if (conn_->nfmark &&
+ Ip::Qos::setSockNfmark(temporaryFd_, conn_->nfmark) < 0)
+ conn_->nfmark = 0;
+#endif
+
+ fd_table[temporaryFd_].tosToServer = conn_->tos;
+ fd_table[temporaryFd_].nfmarkToServer = conn_->nfmark;
+
typedef CommCbMemFunT<Comm::ConnOpener, CommCloseCbParams> abortDialer;
calls_.earlyAbort_ = JobCallback(5, 4, abortDialer, this, Comm::ConnOpener::earlyAbort);
comm_add_close_handler(temporaryFd_, calls_.earlyAbort_);
typedef CommCbMemFunT<Comm::ConnOpener, CommTimeoutCbParams> timeoutDialer;
calls_.timeout_ = JobCallback(5, 4, timeoutDialer, this, Comm::ConnOpener::timeout);
- debugs(5, 3, HERE << conn_ << " timeout " << connectTimeout_);
+ debugs(5, 3, conn_ << " will timeout in " << (deadline_ - squid_curtime));
- // Update the fd_table directly because conn_ is not yet storing the FD
+ // Update the fd_table directly because commSetConnTimeout() needs open conn_
assert(temporaryFd_ < Squid_MaxFD);
assert(fd_table[temporaryFd_].flags.open);
typedef CommTimeoutCbParams Params;
Params ¶ms = GetCommParams<Params>(calls_.timeout_);
params.conn = conn_;
fd_table[temporaryFd_].timeoutHandler = calls_.timeout_;
- fd_table[temporaryFd_].timeout = squid_curtime + (time_t) connectTimeout_;
+ fd_table[temporaryFd_].timeout = deadline_;
- connectStart_ = squid_curtime;
- connect();
+ return true;
}
void
Comm::ConnOpener::connected()
{
- conn_->fd = temporaryFd_;
- temporaryFd_ = -1;
+ Must(temporaryFd_ >= 0);
+ keepFd();
/*
* stats.conn_open is used to account for the number of
- * connections that we have open to the peer, so we can limit
+ * connections that we have open to the CachePeer, so we can limit
* based on the max-conn option. We need to increment here,
* even if the connection may fail.
*/
- if (peer *peer=(conn_->getPeer()))
+ if (CachePeer *peer=(conn_->getPeer()))
++peer->stats.conn_open;
lookupLocalAddress();
* Also, legacy code still depends on comm_local_port() with no access to Comm::Connection
* when those are done comm_local_port can become one of our member functions to do the below.
*/
- fd_table[conn_->fd].flags.open = 1;
+ Must(fd_table[conn_->fd].flags.open);
fd_table[conn_->fd].local_addr = conn_->local;
+
+ sendAnswer(Comm::OK, 0, "Comm::ConnOpener::connected");
}
-/** Make an FD connection attempt.
- * Handles the case(s) when a partially setup connection gets closed early.
- */
+/// Make an FD connection attempt.
void
-Comm::ConnOpener::connect()
+Comm::ConnOpener::doConnect()
{
Must(conn_ != NULL);
-
- // our parent Jobs signal abort by cancelling their callbacks.
- if (callback_ == NULL || callback_->canceled())
- return;
+ Must(temporaryFd_ >= 0);
++ totalTries_;
switch (comm_connect_addr(temporaryFd_, conn_->remote) ) {
- case COMM_INPROGRESS:
- // check for timeout FIRST.
- if (squid_curtime - connectStart_ > connectTimeout_) {
- debugs(5, 5, HERE << conn_ << ": * - ERR took too long already.");
- calls_.earlyAbort_->cancel("Comm::ConnOpener::connect timed out");
- doneConnecting(COMM_TIMEOUT, errno);
- return;
- } else {
- debugs(5, 5, HERE << conn_ << ": COMM_INPROGRESS");
- Comm::SetSelect(temporaryFd_, COMM_SELECT_WRITE, Comm::ConnOpener::InProgressConnectRetry, new Pointer(this), 0);
- }
+ case Comm::INPROGRESS:
+ debugs(5, 5, HERE << conn_ << ": Comm::INPROGRESS");
+ Comm::SetSelect(temporaryFd_, COMM_SELECT_WRITE, Comm::ConnOpener::InProgressConnectRetry, new Pointer(this), 0);
break;
- case COMM_OK:
- debugs(5, 5, HERE << conn_ << ": COMM_OK - connected");
+ case Comm::OK:
+ debugs(5, 5, HERE << conn_ << ": Comm::OK - connected");
connected();
- doneConnecting(COMM_OK, 0);
break;
- default:
+ default: {
+ const int xerrno = errno;
+
++failRetries_;
+ debugs(5, 7, conn_ << ": failure #" << failRetries_ << " <= " <<
+ Config.connect_retries << ": " << xstrerr(xerrno));
- // check for timeout FIRST.
- if (squid_curtime - connectStart_ > connectTimeout_) {
- debugs(5, 5, HERE << conn_ << ": * - ERR took too long to receive response.");
- calls_.earlyAbort_->cancel("Comm::ConnOpener::connect timed out");
- doneConnecting(COMM_TIMEOUT, errno);
- } else if (failRetries_ < Config.connect_retries) {
+ if (failRetries_ < Config.connect_retries) {
debugs(5, 5, HERE << conn_ << ": * - try again");
- eventAdd("Comm::ConnOpener::DelayedConnectRetry", Comm::ConnOpener::DelayedConnectRetry, new Pointer(this), 0.05, 0, false);
+ retrySleep();
return;
} else {
// send ERROR back to the upper layer.
debugs(5, 5, HERE << conn_ << ": * - ERR tried too many times already.");
- calls_.earlyAbort_->cancel("Comm::ConnOpener::connect failed");
- doneConnecting(COMM_ERR_CONNECT, errno);
+ sendAnswer(Comm::ERR_CONNECT, xerrno, "Comm::ConnOpener::doConnect");
}
}
+ }
+}
+
+/// Close and wait a little before trying to open and connect again.
+void
+Comm::ConnOpener::retrySleep()
+{
+ Must(!calls_.sleep_);
+ closeFd();
+ calls_.sleep_ = true;
+ eventAdd("Comm::ConnOpener::DelayedConnectRetry",
+ Comm::ConnOpener::DelayedConnectRetry,
+ new Pointer(this), 0.05, 0, false);
+}
+
+/// cleans up this job sleep state
+void
+Comm::ConnOpener::cancelSleep()
+{
+ if (calls_.sleep_) {
+ // It would be nice to delete the sleep event, but it might be out of
+ // the event queue and in the async queue already, so (a) we do not know
+ // whether we can safely delete the call ptr here and (b) eventDelete()
+ // will assert if the event went async. Thus, we let the event run so
+ // that it deletes the call ptr [after this job is gone]. Note that we
+ // are called only when the job ends so this "hanging event" will do
+ // nothing but deleting the call ptr. TODO: Revise eventDelete() API.
+ // eventDelete(Comm::ConnOpener::DelayedConnectRetry, calls_.sleep);
+ calls_.sleep_ = false;
+ debugs(5, 9, conn_ << " stops sleeping");
+ }
}
/**
Comm::ConnOpener::lookupLocalAddress()
{
struct addrinfo *addr = NULL;
- conn_->local.InitAddrInfo(addr);
+ Ip::Address::InitAddr(addr);
if (getsockname(conn_->fd, addr->ai_addr, &(addr->ai_addrlen)) != 0) {
- debugs(50, DBG_IMPORTANT, "ERROR: Failed to retrieve TCP/UDP details for socket: " << conn_ << ": " << xstrerror());
- conn_->local.FreeAddrInfo(addr);
+ int xerrno = errno;
+ debugs(50, DBG_IMPORTANT, "ERROR: Failed to retrieve TCP/UDP details for socket: " << conn_ << ": " << xstrerr(xerrno));
+ Ip::Address::FreeAddr(addr);
return;
}
conn_->local = *addr;
- conn_->local.FreeAddrInfo(addr);
+ Ip::Address::FreeAddr(addr);
debugs(5, 6, HERE << conn_);
}
Comm::ConnOpener::earlyAbort(const CommCloseCbParams &io)
{
debugs(5, 3, HERE << io.conn);
- doneConnecting(COMM_ERR_CLOSING, io.xerrno); // NP: is closing or shutdown better?
+ calls_.earlyAbort_ = NULL;
+ // NP: is closing or shutdown better?
+ sendAnswer(Comm::ERR_CLOSING, io.xerrno, "Comm::ConnOpener::earlyAbort");
}
/**
void
Comm::ConnOpener::timeout(const CommTimeoutCbParams &)
{
- connect();
+ debugs(5, 5, HERE << conn_ << ": * - ERR took too long to receive response.");
+ calls_.timeout_ = NULL;
+ sendAnswer(Comm::TIMEOUT, ETIMEDOUT, "Comm::ConnOpener::timeout");
}
-/* Legacy Wrapper for the retry event after COMM_INPROGRESS
- * XXX: As soon as Comm::SetSelect() accepts Async calls we can use a ConnOpener::connect call
+/* Legacy Wrapper for the retry event after Comm::INPROGRESS
+ * XXX: As soon as Comm::SetSelect() accepts Async calls we can use a ConnOpener::doConnect call
*/
void
-Comm::ConnOpener::InProgressConnectRetry(int fd, void *data)
+Comm::ConnOpener::InProgressConnectRetry(int, void *data)
{
Pointer *ptr = static_cast<Pointer*>(data);
assert(ptr);
// Ew. we are now outside the all AsyncJob protections.
// get back inside by scheduling another call...
typedef NullaryMemFunT<Comm::ConnOpener> Dialer;
- AsyncCall::Pointer call = JobCallback(5, 4, Dialer, cs, Comm::ConnOpener::connect);
+ AsyncCall::Pointer call = JobCallback(5, 4, Dialer, cs, Comm::ConnOpener::doConnect);
ScheduleCallHere(call);
}
delete ptr;
}
/* Legacy Wrapper for the retry event with small delay after errors.
- * XXX: As soon as eventAdd() accepts Async calls we can use a ConnOpener::connect call
+ * XXX: As soon as eventAdd() accepts Async calls we can use a ConnOpener::restart call
*/
void
Comm::ConnOpener::DelayedConnectRetry(void *data)
// Ew. we are now outside the all AsyncJob protections.
// get back inside by scheduling another call...
typedef NullaryMemFunT<Comm::ConnOpener> Dialer;
- AsyncCall::Pointer call = JobCallback(5, 4, Dialer, cs, Comm::ConnOpener::connect);
+ AsyncCall::Pointer call = JobCallback(5, 4, Dialer, cs, Comm::ConnOpener::restart);
ScheduleCallHere(call);
}
delete ptr;
}
+