HTTP/2: write logs when refusing streams with data.
Refusing streams is known to be incorrectly handled at least by IE, Edge
and Safari. Make sure to provide appropriate logging to simplify fixing
this in the affected browsers.
HTTP/2: send WINDOW_UPDATE instead of RST_STREAM with NO_ERROR.
After the 92464ebace8e change, it has been discovered that not all
clients follow the RFC and handle RST_STREAM with NO_ERROR properly.
Notably, Chrome currently interprets it as INTERNAL_ERROR and discards
the response.
As a workaround, instead of RST_STREAM the maximum stream window update
will be sent, which will let client to send up to 2 GB of a request body
data before getting stuck on flow control. All the received data will
be silently discarded.
See for details:
http://mailman.nginx.org/pipermail/nginx-devel/2016-April/008143.html
https://bugs.chromium.org/p/chromium/issues/detail?id=603182
HTTP/2: refuse streams with data until SETTINGS is acknowledged.
A client is allowed to send requests before receiving and acknowledging
the SETTINGS frame. Such a client having a wrong idea about the stream's
could send the request body that nginx isn't ready to process.
The previous behavior was to send RST_STREAM with FLOW_CONTROL_ERROR in
such case, but it didn't allow retrying requests that have been rejected.
FastCGI: skip special bufs in buffered request body chain.
This prevents forming empty records out of such buffers. Particularly it fixes
double end-of-stream records with chunked transfer encoding, or when HTTP/2 is
used and the END_STREAM flag has been sent without data. In both cases there
is an empty buffer at the end of the request body chain with the "last_buf"
flag set.
The canonical libfcgi, as well as php implementation, tolerates such records,
while the HHVM parser is more strict and drops the connection (ticket #950).
Fixed a regression introduced in rev. 434548349838 that prevented
auto/types/sizeof and auto/types/typedef properly reporting autotest
source code to autoconf.err in case of test failure.
2. Receiving of request body is started only after
the ngx_http_read_client_request_body() call.
The last one fixes the problem when the client_max_body_size value might not be
respected from the right location if the location was changed either during the
process of receiving body or after the whole body had been received.
HTTP/2: sending RST_STREAM with NO_ERROR to discard request body.
RFC 7540 states that "A server can send a complete response prior to the client
sending an entire request if the response does not depend on any portion of the
request that has not been sent and received. When this is true, a server MAY
request that the client abort transmission of a request without error by sending
a RST_STREAM with an error code of NO_ERROR after sending a complete response
(i.e., a frame with the END_STREAM flag)."
This should prevent a client from blocking on the stream window, since it isn't
maintained for closed streams. Currently, quite big initial stream windows are
used, so such blocking is very unlikly, but that will be changed in the further
patches.
Maxim Dounin [Thu, 31 Mar 2016 20:38:33 +0000 (23:38 +0300)]
SSL: initialization changes for OpenSSL 1.1.0.
OPENSSL_config() deprecated in OpenSSL 1.1.0. Additionally,
SSL_library_init(), SSL_load_error_strings() and OpenSSL_add_all_algorithms()
are no longer available if OPENSSL_API_COMPAT is set to 0x10100000L.
The OPENSSL_init_ssl() function is now used instead with appropriate
arguments to trigger the same behaviour. The configure test changed to
use SSL_CTX_set_options().
Deinitialization now happens automatically in OPENSSL_cleanup() called
via atexit(3), so we no longer call EVP_cleanup() and ENGINE_cleanup()
directly.
Maxim Dounin [Thu, 31 Mar 2016 20:38:29 +0000 (23:38 +0300)]
SSL: reasonable version for LibreSSL.
LibreSSL defines OPENSSL_VERSION_NUMBER to 0x20000000L, but uses an old
API derived from OpenSSL at the time LibreSSL forked. As a result, every
version check we use to test for new API elements in newer OpenSSL versions
requires an explicit check for LibreSSL.
To reduce clutter, redefine OPENSSL_VERSION_NUMBER to 0x1000107fL if
LibreSSL is used. The same is done by FreeBSD port of LibreSSL.
Maxim Dounin [Tue, 29 Mar 2016 06:52:15 +0000 (09:52 +0300)]
Win32: replaced NGX_EXDEV with more appropriate error code.
Correct error code for NGX_EXDEV on Windows is ERROR_NOT_SAME_DEVICE,
"The system cannot move the file to a different disk drive".
Previously used ERROR_WRONG_DISK is about wrong diskette in the drive and
is not appropriate.
There is no real difference though, as MoveFile() is able to copy files
between disk drives, and will fail with ERROR_ACCESS_DENIED when asked
to copy directories. The ERROR_NOT_SAME_DEVICE error is only used
by MoveFileEx() when called without the MOVEFILE_COPY_ALLOWED flag.
On Windows there are two possible error codes which correspond to
the EEXIST error code: ERROR_FILE_EXISTS used by CreateFile(CREATE_NEW),
and ERROR_ALREADY_EXISTS used by CreateDirectory().
MoveFile() seems to use both: ERROR_ALREADY_EXISTS when moving within
one filesystem, and ERROR_FILE_EXISTS when copying a file to a different
drive.
Maxim Dounin [Mon, 28 Mar 2016 16:50:19 +0000 (19:50 +0300)]
Upstream: proxy_next_upstream non_idempotent.
By default, requests with non-idempotent methods (POST, LOCK, PATCH)
are no longer retried in case of errors if a request was already sent
to a backend. Previous behaviour can be restored by using
"proxy_next_upstream ... non_idempotent".
Ruslan Ermilov [Mon, 28 Mar 2016 16:29:18 +0000 (19:29 +0300)]
Fixed --test-build-*.
Fixes various aspects of --test-build-devpoll, --test-build-eventport, and
--test-build-epoll.
In particular, if --test-build-devpoll was used on Linux, then "devpoll"
event method would be preferred over "epoll". Also, wrong definitions of
event macros were chosen.
Piotr Sikora [Sat, 27 Feb 2016 01:30:27 +0000 (17:30 -0800)]
Core: allow strings without null-termination in ngx_parse_url().
This fixes buffer over-read while using variables in the "proxy_pass",
"fastcgi_pass", "scgi_pass", and "uwsgi_pass" directives, where result
of string evaluation isn't null-terminated.
Found with MemorySanitizer.
Signed-off-by: Piotr Sikora <piotrsikora@google.com>
Roman Arutyunyan [Fri, 25 Mar 2016 11:10:38 +0000 (14:10 +0300)]
Fixed socket inheritance on reload and binary upgrade.
On nginx reload or binary upgrade, an attempt is made to inherit listen sockets
from the previous configuration. Previously, no check for socket type was made
and the inherited socket could have the wrong type. On binary upgrade, socket
type was not detected at all. Wrong socket type could lead to errors on that
socket due to different logic and unsupported syscalls. For example, a UDP
socket, inherited as TCP, lead to the following error after arrival of a
datagram: "accept() failed (102: Operation not supported on socket)".
It allows to turn off accumulation of small pool allocations into a big
preallocated chunk of memory. This is useful for debugging memory access
with sanitizer, since such accumulation can cover buffer overruns from
being detected.
Core: use ngx_palloc_small() to allocate ngx_pool_large_t.
This structure cannot be allocated as a large block anyway, otherwise that will
result in infinite recursion, since each large allocation requires to allocate
another ngx_pool_large_t.
The room for the structure is guaranteed by the NGX_MIN_POOL_SIZE constant.
Dmitry Volyntsev [Fri, 18 Mar 2016 12:08:21 +0000 (15:08 +0300)]
Cache: added watermark to reduce IO load when keys_zone is full.
When a keys_zone is full then each next request to the cache is
penalized. That is, the cache has to evict older files to get a
slot from the keys_zone synchronously. The patch introduces new
behavior in this scenario. Manager will try to maintain available
free slots in the keys_zone by cleaning old files in the background.
Maxim Dounin [Fri, 18 Mar 2016 03:44:49 +0000 (06:44 +0300)]
Threads: writing via threads pools in event pipe.
The "aio_write" directive is introduced, which enables use of aio
for writing. Currently it is meaningful only with "aio threads".
Note that aio operations can be done by both event pipe and output
chain, so proper mapping between r->aio and p->aio is provided when
calling ngx_event_pipe() and in output filter.
Maxim Dounin [Fri, 18 Mar 2016 03:44:03 +0000 (06:44 +0300)]
Threads: offloading of temp files writing to thread pools.
The ngx_thread_write_chain_to_file() function introduced, which
uses ngx_file_t thread_handler, thread_ctx and thread_task fields.
The task context structure (ngx_thread_file_ctx_t) is the same for
both reading and writing, and can be safely shared as long as
operations are serialized.
The task->handler field is now always set (and not only when task is
allocated), as the same task can be used with different handlers.
The thread_write flag is introduced in the ngx_temp_file_t structure
to explicitly enable use of ngx_thread_write_chain_to_file() in
ngx_write_chain_to_temp_file() when supported by caller.
Maxim Dounin [Fri, 18 Mar 2016 03:43:52 +0000 (06:43 +0300)]
Threads: task pointer stored in ngx_file_t.
This simplifies the interface of the ngx_thread_read() function.
Additionally, most of the thread operations now explicitly set
file->thread_task, file->thread_handler and file->thread_ctx,
to facilitate use of thread operations in other places.
(Potential problems remain with sendfile in threads though - it uses
file->thread_handler as set in ngx_output_chain(), and it should not
be overwritten to an incompatible one.)
Maxim Dounin [Fri, 18 Mar 2016 02:04:45 +0000 (05:04 +0300)]
Fixed timeouts with threaded sendfile() and subrequests.
If a write event happens after sendfile() but before we've got the
sendfile results in the main thread, this write event will be ignored.
And if no more events will happen, the connection will hang.
Removing the events works in the simple cases, but not always, as
in some cases events are added back by an unrelated code. E.g.,
the upstream module adds write event in the ngx_http_upstream_init()
to track client aborts.
Fix is to use wev->complete instead. It is now set to 0 before
a sendfile() task is posted, and it is set to 1 once a write event
happens. If on completion of the sendfile() task wev->complete is 1,
we know that an event happened while we were executing sendfile(), and
the socket is still ready for writing even if sendfile() did not sent
all the data or returned EAGAIN.
Maxim Dounin [Tue, 15 Mar 2016 15:26:59 +0000 (18:26 +0300)]
Truncation detection in sendfilev() on Solaris.
While sendfilev() is documented to return -1 with EINVAL set
if the file was truncated, at least Solaris 11 silently returns 0,
and this results in CPU hog. Added a test to complain appropriately
if 0 is returned.
Maxim Dounin [Tue, 15 Mar 2016 15:26:17 +0000 (18:26 +0300)]
Truncation detection in sendfile() on Linux.
This addresses connection hangs as observed in ticket #504, and
CPU hogs with "aio threads; sendfile on" as reported in the mailing list,
see http://mailman.nginx.org/pipermail/nginx-ru/2016-March/057638.html.
Roman Arutyunyan [Tue, 15 Mar 2016 12:55:23 +0000 (15:55 +0300)]
Stream: post first read events from client and upstream.
The main proxy function ngx_stream_proxy_process() can terminate the stream
session. The code, following it, should check its return code to make sure the
session still exists. This happens in client and upstream initialization
functions. Swapping ngx_stream_proxy_process() call with the code, that
follows it, leaves the same problem vice versa.
In future ngx_stream_proxy_process() will call ngx_stream_proxy_next_upstream()
making it too complicated to know if stream session still exists after this
call.
Now ngx_stream_proxy_process() is called from posted event handlers in both
places with no code following it. The posted event is automatically removed
once session is terminated.
Justin Li [Wed, 9 Mar 2016 03:31:55 +0000 (22:31 -0500)]
Upstream: avoid closing client connection in edge case.
If proxy_cache is enabled, and proxy_no_cache tests true, it was previously
possible for the client connection to be closed after a 304. The fix is to
recheck r->header_only after the final cacheability is determined, and end the
request if no longer cacheable.
If a client sends If-None-Match, and the upstream server returns 200 with a
matching ETag, no body should be returned to the client. At the start of
ngx_http_upstream_send_response proxy_no_cache is not yet tested, thus cacheable
is still 1 and downstream_error is set.
However, by the time the downstream_error check is done in process_request,
proxy_no_cache has been tested and cacheable is set to 0. The client connection
is then closed, regardless of keepalive.
Maxim Dounin [Thu, 10 Mar 2016 18:58:03 +0000 (21:58 +0300)]
Upstream: fixed "zero size buf" alerts with cache (ticket #918).
If caching was used, "zero size buf in output" alerts might appear
in logs if a client prematurely closed connection. Alerts appeared
in the following situation:
- writing to client returned an error, so event pipe
drained all busy buffers leaving body output filters
in an invalid state;
- when upstream response was fully received,
ngx_http_upstream_finalize_request() tried to flush
all pending data.
Fix is to avoid flushing body if p->downstream_error is set.
Maxim Dounin [Thu, 10 Mar 2016 13:50:13 +0000 (16:50 +0300)]
Dynamic modules: do not overwrite old modules on install.
Just using "cp" is incorrect, as it will overwrite old files
possibly used by OS, leading to unexpected effects. Changed
to "mv + cp", much like used for the main binary.
Maxim Dounin [Thu, 3 Mar 2016 18:14:19 +0000 (21:14 +0300)]
Copy filter: fixed sendfile aio handlers to set ctx->aio.
Sendfile handlers (aio preload and thread handler) are called within
ctx->output_filter() in ngx_output_chain(), and hence ctx->aio cannot
be set directly in ngx_output_chain(). Meanwhile, it must be set to
make sure loop within ngx_output_chain() will be properly terminated.
There are no known cases that trigger the problem, though in theory
something like aio + sub filter (something that needs body in memory,
and can also free some memory buffers) + sendfile can result in
"task already active" and "second aio post" alerts.
The fix is to set ctx->aio in ngx_http_copy_aio_sendfile_preload()
and ngx_http_copy_thread_handler().
For consistency, ctx->aio is no longer set explicitly in
ngx_output_chain_copy_buf(), as it's now done in
ngx_http_copy_thread_handler().
Maxim Dounin [Thu, 3 Mar 2016 18:14:12 +0000 (21:14 +0300)]
Fixed sendfile in threads (or with aio preload) and subrequests.
If sendfile in threads is used, it is possible that multiple
subrequests will trigger multiple ngx_linux_sendfile_thread() calls,
as operations are only serialized in output chain based on r->aio,
that is, on subrequest level.
This resulted in "task #N already active" alerts, in particular, when
running proxy_store.t with "aio threads; sendfile on;".
Fix is to tolerate duplicate calls, with an additional safety check
that the file is the same as previously used.
The same problem also affects "aio on; sendfile on;" on FreeBSD
(previously known as "aio sendfile;"), where aio->preload_handler()
could be called multiple times due to similar reasons, resulting in
"second aio post" alerts. Fix is the same as well.
It is also believed that similar problems can arise if a filter
calls the next body filter multiple times for some reason. These are
mostly theoretical though.