Commit Graph

144 Commits

Author SHA1 Message Date
Ondřej Surý
97a5559ae3 Cleanup the isc_<*>mgr_createinc() constructors
Previously, the taskmgr, timermgr and socketmgr had a constructor
variant, that would create the mgr on top of existing appctx.  This was
no longer true and isc_<*>mgr was just calling isc_<*>mgr_create()
directly without any extra code.

This commit just cleans up the extra function.

(cherry picked from commit 3388ef36b3)
2021-04-19 15:57:40 +02:00
Patrick McLean
c5c9c9b83f Add isc_time_now_hires function to get current time with high resolution
The current isc_time_now uses CLOCK_REALTIME_COARSE which only updates
on a timer tick. This clock is generally fine for millisecond accuracy,
but on servers with 100hz clocks, this clock is nowhere near accurate
enough for microsecond accuracy.

This commit adds a new isc_time_now_hires function that uses
CLOCK_REALTIME, which gives the current time, though it is somewhat
expensive to call. When microsecond accuracy is required, it may be
required to use extra resources for higher accuracy.

(cherry picked from commit ebced74b19)
2021-03-20 11:59:21 -07:00
Ondřej Surý
a017ba2615 Fix TCPDNS and TLSDNS timers
After the TCPDNS refactoring the initial and idle timers were broken and
only the tcp-initial-timeout was always applied on the whole TCP
connection.

This broke any TCP connection that took longer than tcp-initial-timeout,
most often this would affect large zone AXFRs.

This commit changes the timeout logic in this way:

  * On TCP connection accept the tcp-initial-timeout is applied
    and the timer is started
  * When we are processing and/or sending any DNS message the timer is
    stopped
  * When we stop processing all DNS messages, the tcp-idle-timeout
    is applied and the timer is started again
2021-03-18 15:16:13 +01:00
Ondřej Surý
86298fd112 Make linker include library ctor/dtor in statically linked libisc
Under normal situation, the linker throws out all symbols from
compilation unit when no symbols are used in the final binary, which is
the case for lib/isc/lib.c.  This commit adds empty function to lib.c
that's being called from different CU (mem.c in this case) and that
makes the linker to include all the symbols including the normally
unreferenced isc__initialize() and isc__shutdown() in the final binary.
2021-02-26 21:19:33 +01:00
Ondřej Surý
45c55b1e7e Add isc_trampoline API to have simple accounting around threads
The current isc_hp API uses internal tid_v variable that gets
incremented for each new thread using hazard pointers.  This tid_v
variable is then used as a index to global shared table with hazard
pointers state.  Since the tid_v is only incremented and never
decremented the table could overflow very quickly if we create set of
threads for short period of time, they finish the work and cease to
exist.  Then we create identical set of threads and so on and so on.
This is not a problem for a normal `named` operation as the set of
threads is stable, but the problematic place are the unit tests where we
test network manager or other APIs (task, timer) that create threads.

This commits adds a thin wrapper around any function called from
isc_thread_create() that adds unique-but-reusable small digit thread id
that can be used as index to f.e. hazard pointer tables.  The trampoline
wrapper ensures that the thread ids will be reused, so the highest
thread_id number doesn't grow indefinitely when threads are created and
destroyed and then created again.  This fixes the hazard pointer table
overflow on machines with many cores. [GL #2396]

(cherry picked from commit cbbecfcc82)
2021-02-26 21:14:17 +01:00
Ondřej Surý
2f0f531ee8 Use library constructor/destructor to initialize OpenSSL
Instead of calling isc_tls_initialize()/isc_tls_destroy() explicitly use
gcc/clang attributes on POSIX and DLLMain on Windows to initialize and
shutdown OpenSSL library.

This resolves the issue when isc_nm_create() / isc_nm_destroy() was
called multiple times and it would call OpenSSL library destructors from
isc_nm_destroy().

At the same time, since we now have introduced the ctor/dtor for libisc,
this commit moves the isc_mem API initialization (the list of the
contexts) and changes the isc_mem_checkdestroyed() to schedule the
checking of memory context on library unload instead of executing the
code immediately.
2021-02-26 17:18:06 +01:00
Ondřej Surý
effe3ee595 Refactor TLSDNS module to work with libuv/ssl directly
* Following the example set in 634bdfb16d, the tlsdns netmgr
  module now uses libuv and SSL primitives directly, rather than
  opening a TLS socket which opens a TCP socket, as the previous
  model was difficult to debug.  Closes #2335.

* Remove the netmgr tls layer (we will have to re-add it for DoH)

* Add isc_tls API to wrap the OpenSSL SSL_CTX object into libisc
  library; move the OpenSSL initialization/deinitialization from dstapi
  needed for OpenSSL 1.0.x to the isc_tls_{initialize,destroy}()

* Add couple of new shims needed for OpenSSL 1.0.x

* When LibreSSL is used, require at least version 2.7.0 that
  has the best OpenSSL 1.1.x compatibility and auto init/deinit

* Enforce OpenSSL 1.1.x usage on Windows

(cherry picked from commit e493e04c0f)
2021-02-26 16:14:50 +01:00
Ondřej Surý
7b9c8b9781 Refactor netmgr and add more unit tests
This is a part of the works that intends to make the netmgr stable,
testable, maintainable and tested.  It contains a numerous changes to
the netmgr code and unfortunately, it was not possible to split this
into smaller chunks as the work here needs to be committed as a complete
works.

NOTE: There's a quite a lot of duplicated code between udp.c, tcp.c and
tcpdns.c and it should be a subject to refactoring in the future.

The changes that are included in this commit are listed here
(extensively, but not exclusively):

* The netmgr_test unit test was split into individual tests (udp_test,
  tcp_test, tcpdns_test and newly added tcp_quota_test)

* The udp_test and tcp_test has been extended to allow programatic
  failures from the libuv API.  Unfortunately, we can't use cmocka
  mock() and will_return(), so we emulate the behaviour with #define and
  including the netmgr/{udp,tcp}.c source file directly.

* The netievents that we put on the nm queue have variable number of
  members, out of these the isc_nmsocket_t and isc_nmhandle_t always
  needs to be attached before enqueueing the netievent_<foo> and
  detached after we have called the isc_nm_async_<foo> to ensure that
  the socket (handle) doesn't disappear between scheduling the event and
  actually executing the event.

* Cancelling the in-flight TCP connection using libuv requires to call
  uv_close() on the original uv_tcp_t handle which just breaks too many
  assumptions we have in the netmgr code.  Instead of using uv_timer for
  TCP connection timeouts, we use platform specific socket option.

* Fix the synchronization between {nm,async}_{listentcp,tcpconnect}

  When isc_nm_listentcp() or isc_nm_tcpconnect() is called it was
  waiting for socket to either end up with error (that path was fine) or
  to be listening or connected using condition variable and mutex.

  Several things could happen:

    0. everything is ok

    1. the waiting thread would miss the SIGNAL() - because the enqueued
       event would be processed faster than we could start WAIT()ing.
       In case the operation would end up with error, it would be ok, as
       the error variable would be unchanged.

    2. the waiting thread miss the sock->{connected,listening} = `true`
       would be set to `false` in the tcp_{listen,connect}close_cb() as
       the connection would be so short lived that the socket would be
       closed before we could even start WAIT()ing

* The tcpdns has been converted to using libuv directly.  Previously,
  the tcpdns protocol used tcp protocol from netmgr, this proved to be
  very complicated to understand, fix and make changes to.  The new
  tcpdns protocol is modeled in a similar way how tcp netmgr protocol.
  Closes: #2194, #2283, #2318, #2266, #2034, #1920

* The tcp and tcpdns is now not using isc_uv_import/isc_uv_export to
  pass accepted TCP sockets between netthreads, but instead (similar to
  UDP) uses per netthread uv_loop listener.  This greatly reduces the
  complexity as the socket is always run in the associated nm and uv
  loops, and we are also not touching the libuv internals.

  There's an unfortunate side effect though, the new code requires
  support for load-balanced sockets from the operating system for both
  UDP and TCP (see #2137).  If the operating system doesn't support the
  load balanced sockets (either SO_REUSEPORT on Linux or SO_REUSEPORT_LB
  on FreeBSD 12+), the number of netthreads is limited to 1.

* The netmgr has now two debugging #ifdefs:

  1. Already existing NETMGR_TRACE prints any dangling nmsockets and
     nmhandles before triggering assertion failure.  This options would
     reduce performance when enabled, but in theory, it could be enabled
     on low-performance systems.

  2. New NETMGR_TRACE_VERBOSE option has been added that enables
     extensive netmgr logging that allows the software engineer to
     precisely track any attach/detach operations on the nmsockets and
     nmhandles.  This is not suitable for any kind of production
     machine, only for debugging.

* The tlsdns netmgr protocol has been split from the tcpdns and it still
  uses the old method of stacking the netmgr boxes on top of each other.
  We will have to refactor the tlsdns netmgr protocol to use the same
  approach - build the stack using only libuv and openssl.

* Limit but not assert the tcp buffer size in tcp_alloc_cb
  Closes: #2061

(cherry picked from commit 634bdfb16d)
2020-12-09 10:46:16 +01:00
Witold Kręcicki
4a854da141 netmgr: server-side TLS support
Add server-side TLS support to netmgr - that includes moving some of the
isc_nm_ functions from tcp.c to a wrapper in netmgr.c calling a proper
tcp or tls function, and a new isc_nm_listentls() function.

Add DoT support to tcpdns - isc_nm_listentlsdns().

(cherry picked from commit b2ee0e9dc3)
2020-12-09 10:46:16 +01:00
Evan Hunt
4598d7b30d add isc_nmhandle_settimeout() function
this function sets the read timeout for the socket associated
with a netmgr handle and, if the timer is running, resets it.
for TCPDNS sockets it also sets the read timeout and resets the
timer on the outer TCP socket.

(cherry picked from commit 4be63c5b00)
2020-12-09 10:46:16 +01:00
Evan Hunt
c919a3338f add netmgr functions to support outgoing DNS queries
- isc_nm_tcpdnsconnect() sets up up an outgoing TCP DNS connection.
- isc_nm_tcpconnect(), _udpconnect() and _tcpdnsconnect() now take a
  timeout argument to ensure connections time out and are correctly
  cleaned up on failure.
- isc_nm_read() now supports UDP; it reads a single datagram and then
  stops until the next time it's called.
- isc_nm_cancelread() now runs asynchronously to prevent assertion
  failure if reading is interrupted by a non-network thread (e.g.
  a timeout).
- isc_nm_cancelread() can now apply to UDP sockets.
- added shim code to support UDP connection in versions of libuv
  prior to 1.27, when uv_udp_connect() was added

all these functions will be used to support outgoing queries in dig,
xfrin, dispatch, etc.

(cherry picked from commit 5dcdc00b93)
2020-12-09 10:46:16 +01:00
Evan Hunt
ba2e9dfb99 change from isc_nmhandle_ref/unref to isc_nmhandle attach/detach
Attaching and detaching handle pointers will make it easier to
determine where and why reference counting errors have occurred.

A handle needs to be referenced more than once when multiple
asynchronous operations are in flight, so callers must now maintain
multiple handle pointers for each pending operation. For example,
ns_client objects now contain:

        - reqhandle:    held while waiting for a request callback (query,
                        notify, update)
        - sendhandle:   held while waiting for a send callback
        - fetchhandle:  held while waiting for a recursive fetch to
                        complete
        - updatehandle: held while waiting for an update-forwarding
                        task to complete

(cherry picked from commit 57b4dde974)
2020-10-01 18:09:35 +02:00
Evan Hunt
bc5ea9d65e use handles for isc_nm_pauseread() and isc_nm_resumeread()
by having these functions act on netmgr handles instead of socket
objects, they can be used in callback functions outside the netgmr.

(cherry picked from commit 55896df79d)
2020-10-01 16:44:43 +02:00
Witold Kręcicki
ebb4d506d6 Add missing libisc.def definitions, netmgr version of isc_sockettype_t.
(cherry picked from commit 25f84ffc68)
2020-10-01 16:44:43 +02:00
Evan Hunt
d9d482e9e2 implement isc_nm_cancelread()
The isc_nm_cancelread() function cancels reading on a connected
socket and calls its read callback function with a 'result'
parameter of ISC_R_CANCELED.

(cherry picked from commit 5191ec8f86)
2020-10-01 16:44:43 +02:00
Evan Hunt
a9061ea123 implement isc_nm_tcpconnect()
the isc_nm_tcpconnect() function establishes a client connection via
TCP.  once the connection is esablished, a callback function will be
called with a newly created network manager handle.

(cherry picked from commit abbb79f9d1)
2020-10-01 16:44:43 +02:00
Evan Hunt
573bcdf932 make isc_nmsocket_{attach,detach}{} functions private
there is no need for a caller to reference-count socket objects.
they need tto be able tto close listener sockets (i.e., those
returned by isc_nm_listen{udp,tcp,tcpdns}), and an isc_nmsocket_close()
function has been added for that. other sockets are only accessed via
handles.

(cherry picked from commit 9e740cad21)
2020-10-01 16:44:43 +02:00
Mark Andrews
ebf16118df Add ISO time stamps to the microsecond
(cherry picked from commit 519b070618)
2020-10-01 00:14:45 +10:00
Ondřej Surý
ebb2b055cc Add isc_hash32() and rename isc_hash_function() to isc_hash64()
As the names suggest the original isc_hash64 function returns 64-bit
long hash values and the isc_hash32() returns 32-bit values.

(cherry picked from commit f59fd49fd8)
2020-07-30 11:57:24 +02:00
Ondřej Surý
1e5df7f3bf Add HalfSipHash 2-4 reference implementation
The HalfSipHash implementation has 32-bit keys and returns 32-bit
value.

(cherry picked from commit 344d66aaff)
2020-07-30 11:57:24 +02:00
Matthijs Mekking
7915327aac Move dst key printtime in separate function
I'd like to use the same functionality (pretty print the datetime
of keytime metadata) in the 'rndc dnssec -status' command.  So it is
better that this logic is done in a separate function.

Since the stdtime.c code have differernt files for unix and win32,
I think the "#ifdef WIN32" define can be dropped.

(cherry picked from commit 9e03f8e8fe)
2020-07-01 09:57:44 +02:00
Mark Andrews
eed4fab37b Report Extended DNS Error codes
(cherry picked from commit b144ae1bb0)
2020-05-13 10:26:39 +10:00
Ondřej Surý
5948a29463 Stop leaking OpenSSL types and defines in the isc/safe.h
The two "functions" that isc/safe.h declared before were actually simple
defines to matching OpenSSL functions.  The downside of the approach was
enforcing all users of the libisc library to explicitly list the include
path to OpenSSL and link with -lcrypto.  By hiding the specific
implementation into the private namespace changing the defines into
simple functions, we no longer enforce this.  In the long run, this
might also allow us to switch cryptographic library implementation
without affecting the downstream users.

(cherry picked from commit ab827ab5bf)
2020-04-28 16:27:39 +02:00
Ondřej Surý
c22c8cb0e1 Stop leaking OpenSSL types and defines in the isc/md.h
The <isc/md.h> header directly included <openssl/evp.h> header which
enforced all users of the libisc library to explicitly list the include
path to OpenSSL and link with -lcrypto.  By hiding the specific
implementation into the private namespace, we no longer enforce this.
In the long run, this might also allow us to switch cryptographic
library implementation without affecting the downstream users.

While making the isc_md_type_t type opaque, the API using the data type
was changed to use the pointer to isc_md_type_t instead of using the
type directly.

(cherry picked from commit 4e114f8ed6)
2020-04-28 15:24:07 +02:00
Witold Kręcicki
365636dbc9 netmgr refactoring: use generic functions when operating on sockets.
tcpdns used transport-specific functions to operate on the outer socket.
Use generic ones instead, and select the proper call in netmgr.c.
Make the missing functions (e.g. isc_nm_read) generic and add type-specific
calls (isc__nm_tcp_read). This is the preparation for netmgr TLS layer.

(cherry picked from commit 5fedd21e16)
2020-04-03 13:44:28 +02:00
Witold Kręcicki
7ab77d009d Add a quota attach function with a callback, some code cleanups.
We introduce a isc_quota_attach_cb function - if ISC_R_QUOTA is returned
at the time the function is called, then a callback will be called when
there's quota available (with quota already attached). The callbacks are
organized as a LIFO queue in the quota structure.
It's needed for TCP client quota -  with old networking code we had one
single place where tcp clients quota was processed so we could resume
accepting when the we had spare slots, but it's gone with netmgr - now
we need to notify the listener/accepter that there's quota available so
that it can resume accepting.

Remove unused isc_quota_force() function.

The isc_quote_reserve and isc_quota_release were used only internally
from the quota.c and the tests.  We should not expose API we are not
using.

(cherry picked from commit d151a10f30)
2020-03-30 10:29:33 +02:00
Witold Kręcicki
32d00479e6 Use libuv-provided uv_{export,import} if available.
We were using our own versions of isc_uv_{export,import} functions
for multithreaded TCP listeners. Upcoming libuv version will
contain proper uv_{export,import} functions - use them if they're
available.
2020-02-18 14:21:16 +01:00
Ondřej Surý
c931d8e417 Merge branch '46-just-use-clang-format-to-reformat-sources' into 'master'
Reformat source code with clang-format

Closes #46

See merge request isc-projects/bind9!2156

(cherry picked from commit 7099e79a9b)

4c3b063e Import Linux kernel .clang-format with small modifications
f50b1e06 Use clang-format to reformat the source files
11341c76 Update the definition files for Windows
df6c1f76 Remove tkey_test (which is no-op anyway)
2020-02-12 14:51:18 +00:00
Witold Kręcicki
493b6a9f33 Make hazard pointers max_threads configurable at runtime.
hp implementation requires an object for each thread accessing
a hazard pointer. previous implementation had a hardcoded
HP_MAX_THREAD value of 128, which failed on machines with lots of
CPU cores (named uses 3n threads). We make isc__hp_max_threads
configurable at startup, with the value set to 4*named_g_cpus.
It's also important for this value not to be too big as we do
linear searches on a list.
2020-01-14 21:26:57 +01:00
Evan Hunt
80a5c9f5c8 associate socket stats counters with netmgr socket objects
- the socket stat counters have been moved from socket.h to stats.h.
- isc_nm_t now attaches to the same stats counter group as
  isc_socketmgr_t, so that both managers can increment the same
  set of statistics
- isc__nmsocket_init() now takes an interface as a paramter so that
  the address family can be determined when initializing the socket.
- based on the address family and socket type, a group of statistics
  counters will be associated with the socket - for example, UDP4Active
  with IPv4 UDP sockets and TCP6Active with IPv6 TCP sockets.  note
  that no counters are currently associated with TCPDNS sockets; those
  stats will be handled by the underlying TCP socket.
- the counters are not actually used by netmgr sockets yet; counter
  increment and decrement calls will be added in a later commit.
2020-01-13 14:05:02 -08:00
Witold Kręcicki
c6c0a9fdba Add isc_uv_export()/isc_uv_import() functions to libuv compatibility layer.
These functions can be used to pass a uv handle between threads in a
safe manner. The other option is to use uv_pipe and pass the uv_handle
via IPC, which is way more complex.  uv_export() and uv_import() functions
existed in libuv at some point but were removed later. This code is
based on the original removed code.

The Windows version of the code uses two functions internal to libuv;
a patch for libuv is attached for exporting these functions.
2020-01-13 10:52:07 -08:00
Ondřej Surý
17deac8b8e Remove unused isc_log_get() function 2020-01-08 11:53:04 +01:00
Ondřej Surý
b1a7ec7481 Remove isc_thread_key API in favor of ISC_THREAD_LOCAL variables
For BIND 9.16+, TLS aware compiler is required, and using
ISC_THREAD_LOCAL is preferred way of using Thread Local Storage.  The
isc_thread_key API is no longer used anywhere and hence was removed from
BIND 9.
2019-12-04 14:17:19 +01:00
Evan Hunt
00333a5c97 netmgr: add shutdown function
- new function isc_nm_shutdown() shuts down all active TCP connections,
  but does not destroy the netmgr.
2019-11-22 16:46:32 -08:00
Evan Hunt
199bd6b623 netmgr: make TCP timeouts configurable
- restore support for tcp-initial-timeout, tcp-idle-timeout,
  tcp-keepalive-timeout and tcp-advertised-timeout configuration
  options, which were ineffective previously.
2019-11-22 16:46:31 -08:00
Evan Hunt
36ee430327 optionally associate a netmgr with a task manager when creating
When a task manager is created, we can now specify an `isc_nm`
object to associate with it; thereafter when the task manager is
placed into exclusive mode, the network manager will be paused.
2019-11-07 11:55:37 -08:00
Witold Kręcicki
70397f9d92 netmgr: libuv-based network manager
This is a replacement for the existing isc_socket and isc_socketmgr
implementation. It uses libuv for asynchronous network communication;
"networker" objects will be distributed across worker threads reading
incoming packets and sending them for processing.

UDP listener sockets automatically create an array of "child" sockets
so each worker can listen separately.

TCP sockets are shared amongst worker threads.

A TCPDNS socket is a wrapper around a TCP socket, which handles the
the two-byte length field at the beginning of DNS messages over TCP.

(Other wrapper socket types can be implemented in the future to handle
DNS over TLS, DNS over HTTPS, etc.)
2019-11-07 11:55:37 -08:00
Evan Hunt
a8c814cb2f implement fixed-size array stack data structure 2019-11-07 11:55:37 -08:00
Witold Kręcicki
402969bf95 implement fetch-and-add array queue data structure
this is a lockless queue based on hazard pointers.
2019-11-07 11:55:37 -08:00
Witold Kręcicki
aa57fa7090 implement hazard pointer data structure
this is a mechanism to allow safe lock-free data structures.
2019-11-07 11:55:37 -08:00
Witold Kręcicki
a5f8374400 add isc_sockaddr_fromsockaddr function
This converts from struct sockaddr to isc_sockaddr_t
2019-11-07 11:55:37 -08:00
Diego Fronza
a544e2e300 Add functions for collecting high-water counters
Add {isc,ns}_stats_{update_if_greater,get_counter}() functions that
are used to set and collect high-water type of statistics.
2019-11-06 09:11:20 +01:00
Ondřej Surý
19fbdef31e Remove unused isc_mem_createx() function
The isc_mem_createx() function was only used in the tests to eliminate using the
default flags (which as of writing this commit message was ISC_MEMFLAG_INTERNAL
and ISC_MEMFLAG_FILL).  This commit removes the isc_mem_createx() function from
the public API.
2019-09-12 09:26:09 +02:00
Mark Andrews
978a37c827 use atomics in lib/isc/win32/app.c 2019-05-24 16:27:40 +10:00
Ondřej Surý
2e7d82443f Convert isc_hash functions to use isc_siphash24 2019-05-21 10:23:13 +00:00
Ondřej Surý
a197df137a Add reference SipHash 2-4 implementation 2019-05-20 19:01:31 +02:00
Ondřej Surý
eb8c9bdd55 Make lib/isc/app.c opaque and thread-safe
This work cleans up the API which includes couple of things:

1. Make the isc_appctx_t type fully opaque

2. Protect all access to the isc_app_t members via stdatomics

3. sigwait() is part of POSIX.1, remove dead non-sigwait code

4. Remove unused code: isc_appctx_set{taskmgr,sockmgr,timermgr}
2019-05-20 18:13:02 +02:00
Evan Hunt
2f3876d187 refactor tcpquota and pipeline refs; allow special-case overrun in isc_quota
- if the TCP quota has been exceeded but there are no clients listening
  for new connections on the interface, we can now force attachment to the
  quota using isc_quota_force(), instead of carrying on with the quota not
  attached.
- the TCP client quota is now referenced via a reference-counted
  'ns_tcpconn' object, one of which is created whenever a client begins
  listening for new connections, and attached to by members of that
  client's pipeline group. when the last reference to the tcpconn
  object is detached, it is freed and the TCP quota slot is released.
- reduce code duplication by adding mark_tcp_active() function
- convert counters to stdatomic

(cherry picked from commit a8dd133d270873b736c1be9bf50ebaa074f5b38f)
(cherry picked from commit 4a8fc979c4)
2019-04-25 16:32:05 +02:00
Witold Kręcicki
0af500a2c5 - Make isc_quota use atomics instead of locks
- Use getters for isc_quota parameters, make fields private
- Fix a potential data race with recursion clients limits logging
2019-01-25 04:26:49 -05:00
Ondřej Surý
e2cdf066ea Remove message catalogs 2019-01-09 23:44:26 +01:00