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.
a) ssl as listen parameter is preferable.
b) ssl_protocols defaults are better because they do not forbid TLS versions
1.1 and 1.2.
c) ssl_session_timeout has sense only with SSL cache.
If a relative path is set by variables, then the ngx_conf_full_name()
function was called while processing requests, which causes allocations
from the cycle pool.
A new function that takes pool as an argument was introduced.
This is done by passing AI_ADDRCONFIG to getaddrinfo().
On Linux, setting net.ipv6.conf.all.disable_ipv6 to 1 will now be
respected.
On FreeBSD, AI_ADDRCONFIG filtering is currently implemented by
attempting to create a datagram socket for the corresponding family,
which succeeds even if the system doesn't in fact have any addresses
of that family configured. That is, if the system with IPv6 support
in the kernel doesn't have IPv6 addresses configured, AI_ADDRCONFIG
will filter out IPv6 only inside a jail without IPv6 addresses or
with IPv6 disabled.
Though there are several MIME types commonly used for JavaScript nowadays,
the most common being "text/javascript", "application/javascript", and
currently used by nginx "application/x-javascript", RFC 4329 prefers
"application/javascript".
The "charset_types" directive's default value was adjusted accordingly.
As per perlxs, C preprocessor directives should be at the first
non-whitespace of a line to avoid interpreting them as comments.
#if and #endif are moved so that there are no blank lines before them
to retain them as part of the function body.
Previously, after sending a header we always sent a last buffer and
finalized a request with code 0, even in case of errors. In some cases
this resulted in a loss of ability to detect the response wasn't complete
(e.g. if Content-Length was removed from a response by gzip filter).
This change tries to propogate to a client information that a response
isn't complete in such cases. In particular, with this change we no longer
pretend a returned response is complete if we wasn't able to create
a temporary file.
If an error code suggests the error wasn't fatal, we flush buffered data
and disable keepalive, then finalize request normally. This allows to to
propogate information about a problem to a client, while still sending all
the data we've got from an upstream.
No semantic changes expected, though some checks are done differently.
In particular, the r->cached flag is no longer explicitly checked. Instead,
we relay on u->header_sent not being set if a response is sent from
a cache.
The NGX_HTTP_CLIENT_CLOSED_REQUEST code is allowed to happen after we
started sending a response (much like NGX_HTTP_REQUEST_TIME_OUT), so there
is no need to reset response code to 0 in this case.
Checks were added to both buffered and unbuffered code paths to detect
and complain if a response is incomplete. Appropriate error codes are
now passed to ngx_http_upstream_finalize_request().
With this change in unbuffered mode we now use u->length set to -1 as an
indicator that EOF is allowed per protocol and used to indicate response
end (much like its with p->length in buffered mode). Proxy module was
changed to set u->length to 1 (instead of previously used -1) in case of
chunked transfer encoding used to comply with the above.
That is, by default we assume that response end is signalled by
a connection close. This seems to be better default, and in line
with u->pipe->length behaviour.
Memcached module was modified accordingly.
In case of upstream eof, only responses with u->pipe->length == -1
are now cached/stored. This ensures that unfinished chunked responses
are not cached.
Note well - previously used checks for u->headers_in.content_length_n are
preserved. This provides an additional level of protection if protol data
disagree with Content-Length header provided (e.g., a FastCGI response
is sent with wrong Content-Length, or an incomple SCGI or uwsgi response),
as well as protects from storing of responses to HEAD requests. This should
be reconsidered if we'll consider caching of responses to HEAD requests.
There is no real difference from previously used 0 as NGX_HTTP_* will
become 0 in ngx_http_upstream_finalize_request(), but the change
preserves information about a timeout a bit longer. Previous use of
ETIMEDOUT in one place was just wrong.
Note well that with cacheable responses there will be a difference
(code in ngx_http_upstream_finalize_request() will store the error
in cache), though this change doesn't touch cacheable case.
Previously, ngx_http_upstream_finalize_request(0) was used in most
cases after errors. While with current code there is no difference,
use of NGX_ERROR allows to pass a bit more information into
ngx_http_upstream_finalize_request().
In all cases ngx_http_upstream_finalize_request() with NGX_ERROR now used.
Previously used NGX_HTTP_INTERNAL_SERVER_ERROR in the subrequest in memory
case don't cause any harm, but inconsistent with other uses.
With previous code the p->temp_file->offset wasn't adjusted if a temp
file was written by the code in ngx_event_pipe_write_to_downstream()
after an EOF, resulting in cache not being used with empty scgi and uwsgi
responses with Content-Length set to 0.
Fix it to call ngx_event_pipe_write_chain_to_temp_file() there instead
of calling ngx_write_chain_to_temp_file() directly.
Previous code called ngx_http_finalize_request() with rc = 0. This is
ok if a response status was already set, but resulted in "000" being
logged if it wasn't. In particular this happened with limit_req
if a connection was prematurely closed during limit_req delay.
After a failed partial match we now check if there is another partial
match in previously matched substring to fix cases like "aab" in "aaab".
The ctx->saved string is now always sent if it's present on return
from the ngx_http_sub_parse() function (and reset accordingly). This
allows to release parts of previously matched data.
If a pattern was partially matched at a response end, partially matched
string wasn't send. E.g., a response "fo" was truncated to an empty response
if partially mathed by a pattern "foo".
