It was used to prevent destroying of request object when there are unsent
frames in queue for the stream. Since it was incremented for each frame
and is only 8 bits long, so it was not very hard to overflow the counter.
Now the stream->queued counter is checked instead.
This adds support so it's possible to explicitly disable SSL Session
Tickets. In order to have good Forward Secrecy support either the
session ticket key has to be reloaded by using nginx' binary upgrade
process or using an external key file and reloading the configuration.
This directive adds another possibility to have good support by
disabling session tickets altogether.
If session tickets are enabled and the process lives for a long a time,
an attacker can grab the session ticket from the process and use that to
decrypt any traffic that occured during the entire lifetime of the
process.
If a request had an empty request body (with Content-Length: 0), and there
were preread data available (e.g., due to a pipelined request in the buffer),
the "zero size buf in output" alert might be logged while proxying the
request to an upstream.
Similar alerts appeared with client_body_in_file_only if a request had an
empty request body.
Not really a strict check (as X-Accel-Expires might be ignored or
contain invalid value), but quite simple to implement and better
than what we have now.
Fallback to synchronous sendfile() now only done on 3rd EBUSY without
any progress in a row. Not falling back is believed to be better
in case of occasional EBUSY, though protection is still needed to
make sure there will be no infinite loop.
This fixes content type set in stub_status and autoindex responses
to be usable in content type checks made by filter modules, such
as charset and sub filters.
There is no need to pass FLAG_FIN as a separate argument since it can always be
detected from the last_buf flag of the last frame buffer.
No functional changes.
Processing events from upstream connection can result in sending queued frames
from other streams. In this case such streams were not added to handling queue
and properly handled.
A global per connection flag was replaced by a per stream flag that indicates
currently sending stream while all other streams can be added to handling
queue.
Conditions for skipping ineligible peers are rewritten to make adding of new
conditions simpler and be in line with the "round_robin" and "least_conn"
modules. No functional changes.
Stricten response header checks: ensure that reserved bits are zeroes,
and that the opcode is "standard query".
Fixed the "zero-length domain name in DNS response" condition.
Renamed ngx_resolver_query_t to ngx_resolver_hdr_t as it describes
the header that is common to DNS queries and answers.
Replaced the magic number 12 by the size of the header structure.
The other changes are self-explanatory.
This flag in SPDY fake write events serves the same purposes as the "ready"
flag in real events, and it must be dropped if request needs to be handled.
Otherwise, it can prevent the request from finalization if ngx_http_writer()
was set, which results in a connection leak.
Found by Xiaochen Wang.
If c->read->ready was reset, but later some data were read from a socket
buffer due to a call to ngx_ssl_recv(), the c->read->ready flag should
be restored if not all data were read from OpenSSL buffers (as kernel
won't notify us about the data anymore).
More details are available here:
http://mailman.nginx.org/pipermail/nginx/2013-November/041178.html
The following new directives are introduced: proxy_cache_revalidate,
fastcgi_cache_revalidate, scgi_cache_revalidate, uwsgi_cache_revalidate.
Default is off. When set to on, they enable cache revalidation using
conditional requests with If-Modified-Since for expired cache items.
As of now, no attempts are made to merge headers given in a 304 response
during cache revalidation with headers previously stored in a cache item.
Headers in a 304 response are only used to calculate new validity time
of a cache item.
We should just call post_handler() when subrequest wants to read body, like
it happens for HTTP since rev. f458156fd46a. An attempt to init request body
for subrequests results in hang if the body was not already read.
Recent Linux versions started to return EOPNOTSUPP to getsockopt() calls
on unix sockets, resulting in log pollution on binary upgrade. Such errors
are silently ignored now.
The accept_filter and deferred options were not applied to sockets
that were added to configuration during binary upgrade cycle.
Signed-off-by: Piotr Sikora <piotr@cloudflare.com>
The 403 (Forbidden) should not overwrite 401 (Unauthorized) as the
latter should be returned with the WWW-Authenticate header to request
authentication by a client.
The problem could be triggered with 3rd party modules and the "deny"
directive, or with auth_basic and auth_request which returns 403
(in 1.5.4+).
Patch by Jan Marc Hoffmann.
Much like with other headers, "add_header Cache-Control $value;" no longer
results in anything added to response headers if $value evaluates to an
empty string.
In order to support key rollover, ssl_session_ticket_key can be defined
multiple times. The first key will be used to issue and resume Session
Tickets, while the rest will be used only to resume them.
ssl_session_ticket_key session_tickets/current.key;
ssl_session_ticket_key session_tickets/prev-1h.key;
ssl_session_ticket_key session_tickets/prev-2h.key;
Please note that nginx supports Session Tickets even without explicit
configuration of the keys and this feature should be only used in setups
where SSL traffic is distributed across multiple nginx servers.
Signed-off-by: Piotr Sikora <piotr@cloudflare.com>
The timeout set is used by OpenSSL as a hint for clients in TLS Session
Tickets. Previous code resulted in a default timeout (5m) used for TLS
Sessions Tickets if there was no session cache configured.
Prodded by Piotr Sikora.
With this change all such frames will be added in front of the output queue, and
will be sent first. It prevents HOL blocking when response with higher priority
is blocked by response with lower priority in the middle of the queue because
the order of their SYN_REPLY frames cannot be changed.
Proposed by Yury Kirpichev.
If an error occurs in a SPDY connection, the c->error flag is set on every fake
request connection, and its read or write event handler is called, in order to
finalize it. But while waiting for request headers, it was a no-op since the
read event handler had been set to ngx_http_empty_handler().
If an error occurs in a SPDY connection, the c->error flag is set on every fake
request connection, and its read or write event handler is called, in order to
finalize it. But while waiting for a request body, it was a no-op since the
read event handler ngx_http_request_handler() calls r->read_event_handler that
had been set to ngx_http_block_reading().
Basically, this does the following two changes (and corresponding
modifications of related code):
1. Does not reset session buffer unless it's reached it's end, and always
wait for LF to terminate command (even if we detected invalid command).
2. Record command name to make it available for handlers (since now we
can't assume that command starts from s->buffer->start).
A server MUST send greeting before other replies, while before this
change in case of smtp_greeting_delay violation the 220 greeting was
sent after several 503 replies to commands received before greeting,
resulting in protocol synchronization loss. Moreover, further commands
were accepted after the greeting.
While closing a connection isn't strictly RFC compliant (RFC 5321
requires servers to wait for a QUIT before closing a connection), it's
probably good enough for practial uses.
With previous code only part of u->buffer might be emptied in case
of special responses, resulting in partial responses seen by SSI set
in case of simple protocols, or spurious errors like "upstream sent
invalid chunked response" in case of complex ones.
This patch fixes incorrect handling of auto redirect in configurations
like:
location /0 { }
location /a- { }
location /a/ { proxy_pass ... }
With previously used sorting, this resulted in the following locations
tree (as "-" is less than "/"):
"/a-"
"/0" "/a/"
and a request to "/a" didn't match "/a/" with auto_redirect, as it
didn't traverse relevant tree node during lookup (it tested "/a-",
then "/0", and then falled back to null location).
To preserve locale use for non-ASCII characters on case-insensetive
systems, libc's tolower() used.
Location tree was always constructed using case-sensitive comparison, even
on case-insensitive systems. This resulted in incorrect operation if
uppercase letters were used in location directives. Notably, the
following config:
location /a { ... }
location /B { ... }
failed to properly map requests to "/B" into "location /B".
Found by using auth_basic.t from mdounin nginx-tests under valgrind.
==10470== Invalid write of size 1
==10470== at 0x43603D: ngx_crypt_to64 (ngx_crypt.c:168)
==10470== by 0x43648E: ngx_crypt (ngx_crypt.c:153)
==10470== by 0x489D8B: ngx_http_auth_basic_crypt_handler (ngx_http_auth_basic_module.c:297)
==10470== by 0x48A24A: ngx_http_auth_basic_handler (ngx_http_auth_basic_module.c:240)
==10470== by 0x44EAB9: ngx_http_core_access_phase (ngx_http_core_module.c:1121)
==10470== by 0x44A822: ngx_http_core_run_phases (ngx_http_core_module.c:895)
==10470== by 0x44A932: ngx_http_handler (ngx_http_core_module.c:878)
==10470== by 0x455EEF: ngx_http_process_request (ngx_http_request.c:1852)
==10470== by 0x456527: ngx_http_process_request_headers (ngx_http_request.c:1283)
==10470== by 0x456A91: ngx_http_process_request_line (ngx_http_request.c:964)
==10470== by 0x457097: ngx_http_wait_request_handler (ngx_http_request.c:486)
==10470== by 0x4411EE: ngx_epoll_process_events (ngx_epoll_module.c:691)
==10470== Address 0x5866fab is 0 bytes after a block of size 27 alloc'd
==10470== at 0x4A074CD: malloc (vg_replace_malloc.c:236)
==10470== by 0x43B251: ngx_alloc (ngx_alloc.c:22)
==10470== by 0x421B0D: ngx_malloc (ngx_palloc.c:119)
==10470== by 0x421B65: ngx_pnalloc (ngx_palloc.c:147)
==10470== by 0x436368: ngx_crypt (ngx_crypt.c:140)
==10470== by 0x489D8B: ngx_http_auth_basic_crypt_handler (ngx_http_auth_basic_module.c:297)
==10470== by 0x48A24A: ngx_http_auth_basic_handler (ngx_http_auth_basic_module.c:240)
==10470== by 0x44EAB9: ngx_http_core_access_phase (ngx_http_core_module.c:1121)
==10470== by 0x44A822: ngx_http_core_run_phases (ngx_http_core_module.c:895)
==10470== by 0x44A932: ngx_http_handler (ngx_http_core_module.c:878)
==10470== by 0x455EEF: ngx_http_process_request (ngx_http_request.c:1852)
==10470== by 0x456527: ngx_http_process_request_headers (ngx_http_request.c:1283)
==10470==
The same path names with different "data" context should not be allowed.
In particular it rejects configurations like this:
proxy_cache_path /var/cache/ keys_zone=one:10m max_size=1g inactive=5m;
proxy_cache_path /var/cache/ keys_zone=two:20m max_size=4m inactive=30s;
The SSL_CTX_load_verify_locations() may leave errors in the error queue
while returning success (e.g. if there are duplicate certificates in the file
specified), resulting in "ignoring stale global SSL error" alerts later
at runtime.
Casts between pointers and integers produce warnings on size mismatch. To
silence them, cast to (u)intptr_t should be used. Prevoiusly, casts to
ngx_(u)int_t were used in some cases, and several ngx_int_t expressions had
no casts.
As of now it's mostly style as ngx_int_t is defined as intptr_t.
On win32, time_t is 64 bits wide by default, and passing an ngx_msec_int_t
argument for %T format specifier doesn't work. This doesn't manifest itself
on other platforms as time_t and ngx_msec_int_t are usually of the same size.
Several warnings silenced, notably (ngx_socket_t) -1 is now checked
on socket operations instead of -1, as ngx_socket_t is unsigned on win32
and gcc complains on comparison.
With this patch, it's now possible to compile nginx using mingw gcc,
with options we normally compile on win32.
Several false positive warnings silenced, notably W8012 "Comparing
signed and unsigned" (due to u_short values promoted to int), and
W8072 "Suspicious pointer arithmetic" (due to large type values added
to pointers).
With this patch, it's now again possible to compile nginx using bcc32,
with options we normally compile on win32 minus ipv6 and ssl.
Precompiled headers are disabled as they lead to internal compiler errors
with long configure lines. Couple of false positive warnings silenced.
Various win32 typedefs are adjusted to work with Open Watcom C 1.9 headers.
With this patch, it's now again possible to compile nginx using owc386,
with options we normally compile on win32 minus ipv6 and ssl.
It was introduced in Linux 2.6.39, glibc 2.14 and allows to obtain
file descriptors without actually opening files. Thus made it possible
to traverse path with openat() syscalls without the need to have read
permissions for path components. It is effectively emulates O_SEARCH
which is missing on Linux.
O_PATH is used in combination with O_RDONLY. The last one is ignored
if O_PATH is used, but it allows nginx to not fail when it was built on
modern system (i.e. glibc 2.14+) and run with a kernel older than 2.6.39.
Then O_PATH is unknown to the kernel and ignored, while O_RDONLY is used.
Sadly, fstat() is not working with O_PATH descriptors till Linux 3.6.
As a workaround we fallback to fstatat() with the AT_EMPTY_PATH flag
that was introduced at the same time as O_PATH.
It is believed to be better than fallback to HTTP/0.9, because most of
the clients at present time support HTTP/1.0. It allows nginx to return
error response code for them in cases when it fail to parse request line,
and therefore fail to detect client protocol version.
Even if the client does not support HTTP/1.0, this assumption should not
cause any harm, since from the HTTP/0.9 point of view it still a valid
response.
Without u->header_sent set a special response might be generated following
an upgraded connection. The problem appeared in 1ccdda1f37f3 (1.5.3).
Catched by "header already sent" alerts in 1.5.4 after upstream timeouts.
This allows to approach "server_name" values specified below the
"valid_referers" directive when used within the "server_names" parameter, e.g.:
server_name example.org;
valid_referers server_names;
server_name example.com;
As a bonus, this fixes bogus error with "server_names" specified several times.
The server_name regexes are normally compiled for case-sensitive matching.
This violates case-insensitive obligations in the referer module. To fix
this, the host string is converted to lower case before matching.
Previously server_name regex was executed against the whole referer string
after dropping the scheme part. This could led to an improper matching, e.g.:
server_name ~^localhost$;
valid_referers server_names;
Referer: http://localhost/index.html
It was changed to look only at the hostname part.
The server_name regexes are separated into another array to not clash with
regular regexes.
If Content-Length header is not set, and the image size is larger than the
buffer size, client will hang until a timeout occurs.
Now NGX_HTTP_UNSUPPORTED_MEDIA_TYPE is returned immediately.
diff -r d1403de41631 -r 4fae04f332b4
src/http/modules/ngx_http_image_filter_module.c
Missing call to ngx_http_run_posted_request() resulted in a main request hang
if subrequest's ssl handshake with an upstream server failed for some reason.
Reported by Aviram Cohen.
While ngx_get_full_name() might have a bit more descriptive arguments,
the ngx_conf_full_name() is generally easier to use when parsing
configuration and limits exposure of cycle->prefix / cycle->conf_prefix
details.
They refer to the same socket descriptor as our real connection, and
deleting them will stop processing of the connection.
Events of fake connections must not be activated, and if it happened there
is nothing we can do. The whole processing should be terminated as soon as
possible, but it is not obvious how to do this safely.
A quote from SPDY draft 2 specification: "The length of each name and
value must be greater than zero. A receiver of a zero-length name or
value must send a RST_STREAM with code PROTOCOL error."
But it appears that Chrome browser allows sending requests over SPDY/2
connection using JavaScript that contain headers with empty values.
For better compatibility across SPDY clients and to be compliant with
HTTP, such headers are no longer rejected.
Also, it is worth noting that in SPDY draft 3 the statement has been
changed so that it permits empty values for headers.
It was broken in 8e446a2daf48 when the NGX_SENDFILE_LIMIT constant was added
to ngx_linux_sendfile_chain.c having the same name as already defined one in
ngx_linux_config.h.
The newer is needed to overcome a bug in old Linux kernels by limiting the
number of bytes to send per sendfile() syscall. The older is used with
sendfile() on ancient kernels that works with 32-bit offsets only.
One of these renamed to NGX_SENDFILE_MAXSIZE.
When matching a compiled regex against value in the "Referer" header field,
the length was calculated incorrectly for strings that start from "https://".
This might cause matching to fail for regexes with end-of-line anchors.
Patch by Liangbin Li.
In ngx_*_sendfile_chain() when calculating pointer to a first
non-zero sized buf, use "in" as iterator. This fixes processing
of zero sized buf(s) after EINTR. Otherwise function can return
zero sized buf to caller, and later ngx_http_write_filter()
logs warning.