The ngx_http_parse_complex_uri() function cannot make URI longer and does
not null-terminate URI, so there is no need to allocate an extra byte. This
allocation appears to be a leftover from changes in 461:a88a3e4e158f (0.1.5),
where null-termination of r->uri and many other strings was removed.
When the request line contains request-target in the absolute-URI form,
it can contain path-empty instead of a single slash (see RFC 7230, RFC 3986).
Previously, the ngx_http_parse_request_line() function only accepted empty
path when there was no query string.
With this change, non-empty query is also correctly handled. That is,
request line "GET http://example.com?foo HTTP/1.1" is accepted and results
in $uri "/" and $args "foo".
Note that $request_uri remains "?foo", similarly to how spaces in URIs
are handled. Providing "/?foo", similarly to how "/" is provided for
"GET http://example.com HTTP/1.1", requires allocation.
When doing lingering close, the socket was first shut down for writing,
so SSL shutdown initiated after lingering close was not able to send
the close_notify alerts (ticket #2056).
The fix is to call ngx_ssl_shutdown() before shutting down the socket.
In some cases it might be needed to reject SSL handshake based on SNI
server name provided, for example, to make sure an invalid certificate
is not returned to clients trying to contact a name-based virtual server
without SSL configured. Previously, a "ssl_ciphers aNULL;" was used for
this. This workaround, however, is not compatible with TLSv1.3, in
particular, when using BoringSSL, where it is not possible to configure
TLSv1.3 ciphers at all.
With this change, the ssl_reject_handshake directive is introduced,
which instructs nginx to reject SSL handshakes with an "unrecognized_name"
alert in a particular server block.
For example, to reject handshake with names other than example.com,
one can use the following configuration:
server {
listen 443 ssl;
ssl_reject_handshake on;
}
server {
listen 443 ssl;
server_name example.com;
ssl_certificate example.com.crt;
ssl_certificate_key example.com.key;
}
The following configuration can be used to reject all SSL handshakes
without SNI server name provided:
server {
listen 443 ssl;
ssl_reject_handshake on;
}
server {
listen 443 ssl;
server_name ~^;
ssl_certificate example.crt;
ssl_certificate_key example.key;
}
Additionally, the ssl_reject_handshake directive makes configuring
certificates for the default server block optional. If no certificates
are configured in the default server for a given listening socket,
certificates must be defined in all non-default server blocks with
the listening socket in question.
Previously the default server configuration context was used until the
:authority or host header was parsed. This led to using the configuration
parameters like client_header_buffer_size or request_pool_size from the default
server rather than from the server selected by SNI.
Also, the switch to the right server log is implemented. This issue manifested
itself as QUIC stream being logged to the default server log until :authority
or host is parsed.
Initially, client certificate verification didn't work due to the missing
hc->ssl on a QUIC stream, which is started to be set in 7738:7f0981be07c4.
Then it was lost in 7999:0d2b2664b41c introducing "quic" listen parameter.
This change re-adds hc->ssl back for all QUIC connections, similar to SSL.
In rare cases, such as memory allocation failure, SSL_set_SSL_CTX() returns
NULL, which could mean that a different SSL configuration has not been set.
Note that this new behaviour seemingly originated in OpenSSL-1.1.0 release.
As per HTTP/3 draft 29, section 4.1:
When the server does not need to receive the remainder of the request,
it MAY abort reading the request stream, send a complete response, and
cleanly close the sending part of the stream.
Sending shutdown when ngx_http_test_reading() detects the connection is
closed can result in "SSL_shutdown() failed (SSL: ... bad write retry)"
critical log messages if there are blocked writes.
Fix is to avoid sending shutdown via the c->ssl->no_send_shutdown flag,
similarly to how it is done in ngx_http_keepalive_handler() for kqueue
when pending EOF is detected.
Reported by Jan Prachař
(http://mailman.nginx.org/pipermail/nginx-devel/2018-December/011702.html).
This ensures that copying won't write more than the buffer size
even if the buffer comes from hc->free and it is smaller than the large
client header buffer size in the virtual host configuration. This might
happen if size of large client header buffers is different in name-based
virtual hosts, similarly to the problem with number of buffers fixed
in 6926:e662cbf1b932.
Previously this function generated an error trying to figure out if client shut
down the write end of the connection. The reason for this error was that a
QUIC stream has no socket descriptor. However checking for eof is not the
right thing to do for an HTTP/3 QUIC stream since HTTP/3 clients are expected
to shut down the write end of the stream after sending the request.
Now the function handles QUIC streams separately. It checks if c->read->error
is set. The error flags for c->read and c->write are now set for all streams
when closing the QUIC connection instead of setting the pending_eof flag.
Previously errors led only to closing streams.
To simplify closing QUIC connection from a QUIC stream context, new macro
ngx_http_v3_finalize_connection() is introduced. It calls
ngx_quic_finalize_connection() for the parent connection.
Previously dynamic table was not functional because of zero limit on its size
set by default. Now the following changes enable it:
- new directives to set SETTINGS_QPACK_MAX_TABLE_CAPACITY and
SETTINGS_QPACK_BLOCKED_STREAMS
- send settings with SETTINGS_QPACK_MAX_TABLE_CAPACITY and
SETTINGS_QPACK_BLOCKED_STREAMS to the client
- send Insert Count Increment to the client
- send Header Acknowledgement to the client
- evict old dynamic table entries on overflow
- decode Required Insert Count from client
- block stream if Required Insert Count is not reached
Also, if both are present, require that they have the same value. These
requirements are specified in HTTP/3 draft 28.
Current implementation of HTTP/2 treats ":authority" and "Host"
interchangeably. New checks only make sure at least one of these values is
present in the request. A similar check existed earlier and was limited only
to HTTP/1.1 in 38c0898b6df7.
OCSP validation for client certificates is enabled by the "ssl_ocsp" directive.
OCSP responder can be optionally specified by "ssl_ocsp_responder".
When session is reused, peer chain is not available for validation.
If the verified chain contains certificates from the peer chain not available
at the server, validation will fail.
Preserving pointers within the client buffer is not needed for HTTP/3 because
all data is either allocated from pool or static. Unlike with HTTP/1, data
typically cannot be referenced directly within the client buffer. Trying to
preserve NULLs or external pointers lead to broken pointers.
Also, reverted changes in ngx_http_alloc_large_header_buffer() not relevant
for HTTP/3 to minimize diff to mainstream.
New field r->parse_start is introduced to substitute r->request_start and
r->header_name_start for request length accounting. These fields only work for
this purpose in HTTP/1 because HTTP/1 request line and header line start with
these values.
Also, error logging is now fixed to output the right part of the request.
As per HTTP/3 draft 27, a request or response containing uppercase header
field names MUST be treated as malformed. Also, existing rules applied
when parsing HTTP/1 header names are also applied to HTTP/3 header names:
- null character is not allowed
- underscore character may or may not be treated as invalid depending on the
value of "underscores_in_headers"
- all non-alphanumeric characters with the exception of '-' are treated as
invalid
Also, the r->locase_header field is now filled while parsing an HTTP/3
header.
Error logging for invalid headers is fixed as well.
The first one parses pseudo-headers and is analagous to the request line
parser in HTTP/1. The second one parses regular headers and is analogous to
the header parser in HTTP/1.
Additionally, error handling of client passing malformed uri is now fixed.
For ngx_http_process_request() part to work, this required to set both
r->http_connection->ssl and c->ssl on a QUIC stream. To avoid damaging
global SSL object, ngx_ssl_shutdown() is managed to ignore QUIC streams.
- integer parameters can be configured using the following directives:
quic_max_idle_timeout
quic_max_ack_delay
quic_max_packet_size
quic_initial_max_data
quic_initial_max_stream_data_bidi_local
quic_initial_max_stream_data_bidi_remote
quic_initial_max_stream_data_uni
quic_initial_max_streams_bidi
quic_initial_max_streams_uni
quic_ack_delay_exponent
quic_active_migration
quic_active_connection_id_limit
- only following parameters are actually sent:
active_connection_id_limit
initial_max_streams_uni
initial_max_streams_bidi
initial_max_stream_data_bidi_local
initial_max_stream_data_bidi_remote
initial_max_stream_data_uni
(other parameters are to be added into ngx_quic_create_transport_params()
function as needed, should be easy now)
- draft 24 and draft 27 are now supported
(at compile-time using quic_version macro)
- events handling moved into src/event/ngx_event_quic.c
- http invokes once ngx_quic_run() and passes stream callback
(diff to original http_request.c is now minimal)
- streams are stored in rbtree using ID as a key
- when a new stream is registered, appropriate callback is called
- ngx_quic_stream_t type represents STREAM and stored in c->qs
When "aio" or "aio threads" is used while processing the response body of an
in-memory background subrequest, the subrequest could be finalized with an aio
operation still in progress. Upon aio completion either parent request is
woken or the old r->write_event_handler is called again. The latter may result
in request errors. In either case post_subrequest handler is never called with
the full response body, which is typically expected when using in-memory
subrequests.
Currently in nginx background subrequests are created by the upstream module
and the mirror module. The issue does not manifest itself with these
subrequests because they are header-only. But it can manifest itself with
third-party modules which create in-memory background subrequests.
Introduced ngx_quic_input() and ngx_quic_output() as interface between
nginx and protocol. They are the only functions that are exported.
While there, added copyrights.
Duplicate "Host" headers were allowed in nginx 0.7.0 (revision b9de93d804ea)
as a workaround for some broken Motorola phones which used to generate
requests with two "Host" headers[1]. It is believed that this workaround
is no longer relevant.
[1] http://mailman.nginx.org/pipermail/nginx-ru/2008-May/017845.html
The "identity" transfer coding has been removed in RFC 7230. It is
believed that it is not used in real life, and at the same time it
provides a potential attack vector.
We anyway do not support more than one transfer encoding, so accepting
requests with multiple Transfer-Encoding headers doesn't make sense.
Further, we do not handle multiple headers, and ignore anything but
the first header.
Reported by Filippo Valsorda.
Server name callback is always called by OpenSSL, even
if server_name extension is not present in ClientHello. As such,
checking c->ssl->handshaked before the SSL_get_servername() result
should help to more effectively prevent renegotiation in
OpenSSL 1.1.0 - 1.1.0g, where neither SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS
nor SSL_OP_NO_RENEGOTIATION is available.
Notably this affects various allocation errors, and should generally
improve things if an allocation error actually happens during a callback.
Depending on the OpenSSL version, returning an error can result in
either SSL_R_CALLBACK_FAILED or SSL_R_CLIENTHELLO_TLSEXT error from
SSL_do_handshake(), so both errors were switched to the "info" level.
OpenSSL 1.1.1 does not save server name to the session if server name
callback returns anything but SSL_TLSEXT_ERR_OK, thus breaking
the $ssl_server_name variable in resumed sessions.
Since $ssl_server_name can be used even if we've selected the default
server and there are no other servers, it looks like the only viable
solution is to always return SSL_TLSEXT_ERR_OK regardless of the actual
result.
To fix things in the stream module as well, added a dummy server name
callback which always returns SSL_TLSEXT_ERR_OK.
A virtual server may have no SSL context if it does not have certificates
defined, so we have to use config of the ngx_http_ssl_module from the
SSL context in the certificate callback. To do so, it is now passed as
the argument of the callback.
The stream module doesn't really need any changes, but was modified as
well to match http code.
Passwords have to be copied to the configuration pool to be used
at runtime. Also, to prevent blocking on stdin (with "daemon off;")
an empty password list is provided.
To make things simpler, password handling was modified to allow
an empty array (with 0 elements and elts set to NULL) as an equivalent
of an array with 1 empty password.
To evaluate variables, a request is created in the certificate callback,
and then freed. To do this without side effects on the stub_status
counters and connection state, an additional function was introduced,
ngx_http_alloc_request().
Only works with OpenSSL 1.0.2+, since there is no SSL_CTX_set_cert_cb()
in older versions.
In e3ba4026c02d (1.15.4) nginx own renegotiation checks were disabled
if SSL_OP_NO_RENEGOTIATION is available. But since SSL_OP_NO_RENEGOTIATION
is only set on a connection, not in an SSL context, SSL_clear_option()
removed it as long as a matching virtual server was found. This resulted
in a segmentation fault similar to the one fixed in a6902a941279 (1.9.8),
affecting nginx built with OpenSSL 1.1.0h or higher.
To fix this, SSL_OP_NO_RENEGOTIATION is now explicitly set in
ngx_http_ssl_servername() after adjusting options. Additionally, instead
of c->ssl->renegotiation we now check c->ssl->handshaked, which seems
to be a more correct flag to test, and will prevent the segmentation fault
from happening even if SSL_OP_NO_RENEGOTIATION is not working.
Socket leak was observed in the following configuration:
error_page 400 = /close;
location = /close {
return 444;
}
The problem is that "return 444" triggers termination of the request,
and due to error_page termination thinks that it needs to use a posted
request to clear stack. But at the early request processing where 400
errors are generated there are no ngx_http_run_posted_requests() calls,
so the request is only terminated after an external event.
Variants of the problem include "error_page 497" instead (ticket #695)
and various other errors generated during early request processing
(405, 414, 421, 494, 495, 496, 501, 505).
The same problem can be also triggered with "return 499" and "return 408"
as both codes trigger ngx_http_terminate_request(), much like "return 444".
To fix this, the patch adds ngx_http_run_posted_requests() calls to
ngx_http_process_request_line() and ngx_http_process_request_headers()
functions, and to ngx_http_v2_run_request() and ngx_http_v2_push_stream()
functions in HTTP/2.
Since the ngx_http_process_request() function is now only called via
other functions which call ngx_http_run_posted_requests(), the call
there is no longer needed and was removed.
The "do { c->recv() } while (c->read->ready)" form used in the
ngx_http_lingering_close_handler() is not really correct, as for
example with SSL c->read->ready may be still set when returning NGX_AGAIN
due to SSL_ERROR_WANT_WRITE. Therefore the above might be an infinite loop.
This doesn't really matter in lingering close, as we shutdown write side
of the socket anyway and also disable renegotiation (and even without shutdown
and with renegotiation it requires using very large certificate chain and
tuning socket buffers to trigger SSL_ERROR_WANT_WRITE). But for the sake of
correctness added an NGX_AGAIN check.
In OpenSSL 1.1.0 the SSL_CTRL_CLEAR_OPTIONS macro was removed, so
conditional compilation test on it results in SSL_clear_options()
and SSL_CTX_clear_options() not being used. Notably, this caused
"ssl_prefer_server_ciphers off" to not work in SNI-based virtual
servers if server preference was switched on in the default server.
It looks like the only possible fix is to test OPENSSL_VERSION_NUMBER
explicitly.
In mail and stream modules, no certificate provided is a fatal condition,
much like with the "ssl" and "starttls" directives.
In http, "listen ... ssl" can be used in a non-default server without
certificates as long as there is a certificate in the default one, so
missing certificate is only fatal for default servers.
According to the gRPC protocol specification, the "TE" header is used
to detect incompatible proxies, and at least grpc-c server rejects
requests without "TE: trailers".
To preserve the logic, we have to pass "TE: trailers" to the backend if
and only if the original request contains "trailers" in the "TE" header.
Note that no other TE values are allowed in HTTP/2, so we have to remove
anything else.
This fixes segfault in configurations with multiple virtual servers sharing
the same port, where a non-default virtual server block misses certificate.
The ngx_http_upstream_process_upgraded() did not handle c->close request,
and upgraded connections do not use the write filter. As a result,
worker_shutdown_timeout did not affect upgraded connections (ticket #1419).
Fix is to handle c->close in the ngx_http_request_handler() function, thus
covering most of the possible cases in http handling.
Additionally, mail proxying did not handle neither c->close nor c->error,
and thus worker_shutdown_timeout did not work for mail connections. Fix is
to add c->close handling to ngx_mail_proxy_handler().
Also, added explicit handling of c->close to stream proxy,
ngx_stream_proxy_process_connection(). This improves worker_shutdown_timeout
handling in stream, it will no longer wait for some data being transferred
in a connection before closing it, and will also provide appropriate
logging at the "info" level.
Example:
ngx_table_elt_t *h;
h = ngx_list_push(&r->headers_out.trailers);
if (h == NULL) {
return NGX_ERROR;
}
ngx_str_set(&h->key, "Fun");
ngx_str_set(&h->value, "with trailers");
h->hash = ngx_hash_key_lc(h->key.data, h->key.len);
The code above adds "Fun: with trailers" trailer to the response.
Modules that want to emit trailers must set r->expect_trailers = 1
in header filter, otherwise they might not be emitted for HTTP/1.1
responses that aren't already chunked.
This change also adds $sent_trailer_* variables.
Signed-off-by: Piotr Sikora <piotrsikora@google.com>
If the main request was finalized while a background request performed an
asynchronous operation, the main request ended up in ngx_http_writer() and was
not finalized until a network event or a timeout. For example, cache
background update with aio enabled made nginx unable to process further client
requests or close the connection, keeping it open until client closes it.
Now regular finalization of the main request is not suspended because of an
asynchronous operation in another request.
If a background request was terminated while an asynchronous operation was in
progress, background request's write event handler was changed to
ngx_http_request_finalizer() and never called again.
Now, whenever a request is terminated while an asynchronous operation is in
progress, connection error flag is set to make further finalizations of any
request with this connection lead to termination.
These issues appeared in 1aeaae6e9446 (not yet released).
With OpenSSL 1.1.0+, the workaround for handshake buffer size as introduced
in a720f0b0e083 (ticket #413) no longer works, as OpenSSL no longer exposes
handshake buffers, see https://github.com/openssl/openssl/commit/2e7dc7cd688.
Moreover, it is no longer possible to adjust handshake buffers at all now.
To avoid additional RTT if handshake uses more than 4k we now set TCP_NODELAY
on SSL connections before handshake. While this still results in sub-optimal
network utilization due to incomplete packets being sent, it seems to be
better than nothing.
Previously, cache background update might not work as expected, making client
wait for it to complete before receiving the final part of a stale response.
This could happen if the response could not be sent to the client socket in one
filter chain call.
Now background cache update is done in a background subrequest. This type of
subrequest does not block any other subrequests or the main request.
