The configuration handling code has changed to look similar to the proxy_store
directive and friends. This simplifies adding variable support in the following
patch.
No functional changes.
Currently, storing and caching mechanisms cannot work together, and a
configuration error is thrown when the proxy_store and proxy_cache
directives (as well as their friends) are configured on the same level.
But configurations like in the example below were allowed and could result
in critical errors in the error log:
proxy_store on;
location / {
proxy_cache one;
}
Only proxy_store worked in this case.
For more predictable and errorless behavior these directives now prevent
each other from being inherited from the previous level.
This changes internal API related to handling of the "store"
flag in ngx_http_upstream_conf_t. Previously, a non-null value
of "store_lengths" was enough to enable store functionality with
custom path. Now, the "store" flag is also required to be set.
No functional changes.
The proxy_store, fastcgi_store, scgi_store and uwsgi_store were inherited
incorrectly if a directive with variables was defined, and then redefined
to the "on" value, i.e. in configurations like:
proxy_store /data/www$upstream_http_x_store;
location / {
proxy_store on;
}
In the following configuration request was sent to a backend without
URI changed to '/' due to if:
location /proxy-pass-uri {
proxy_pass http://127.0.0.1:8080/;
set $true 1;
if ($true) {
# nothing
}
}
Fix is to inherit conf->location from the location where proxy_pass was
configured, much like it's done with conf->vars.
The proxy_pass directive and other handlers are not expected to be inherited
into nested locations, but there is a special code to inherit upstream
handlers into limit_except blocks, as well as a configuration into if{}
blocks. This caused incorrect behaviour in configurations with nested
locations and limit_except blocks, like this:
location / {
proxy_pass http://u;
location /inner/ {
# no proxy_pass here
limit_except GET {
# nothing
}
}
}
In such a configuration the limit_except block inside "location /inner/"
unexpectedly used proxy_pass defined in "location /", while it shouldn't.
Fix is to avoid inheritance of conf->upstream.upstream (and
conf->proxy_lengths) into locations which don't have noname flag.
Instead of independant inheritance of conf->upstream.upstream (proxy_pass
without variables) and conf->proxy_lengths (proxy_pass with variables)
we now test them both and inherit only if neither is set. Additionally,
SSL context is also inherited only in this case now.
Based on the patch by Alexey Radkov.
The upstream modules remove and alter a number of client headers
before sending the request to upstream. This set of headers is
smaller or even empty when cache is disabled.
It's still possible that a request in a cache-enabled location is
uncached, for example, if cache entry counter is below min_uses.
In this case it's better to alter a smaller set of headers and
pass more client headers to backend unchanged. One of the benefits
is enabling server-side byte ranges in such requests.
Once this age is reached, the cache lock is discarded and another
request can acquire the lock. Requests which failed to acquire
the lock are not allowed to cache the response.
The new directives {proxy,fastcgi,scgi,uwsgi,memcached}_next_upstream_tries
and {proxy,fastcgi,scgi,uwsgi,memcached}_next_upstream_timeout limit
the number of upstreams tried and the maximum time spent for these tries
when searching for a valid upstream.
The ngx_http_proxy_rewrite_cookie() function expects the value of the
"Set-Cookie" header to be null-terminated, and for headers obtained
from proxied server it is usually true.
Now the ngx_http_proxy_rewrite() function preserves the null character
while rewriting headers.
This fixes accessing memory outside of rewritten value if both the
"proxy_cookie_path" and "proxy_cookie_domain" directives are used in
the same location.
These directives allow to switch on Server Name Indication (SNI) while
connecting to upstream servers.
By default, proxy_ssl_server_name is currently off (that is, no SNI) and
proxy_ssl_name is set to a host used in the proxy_pass directive.
The SSL_CTX_set_cipher_list() may fail if there are no valid ciphers
specified in proxy_ssl_ciphers / uwsgi_ssl_ciphers, resulting in
SSL context leak.
In theory, ngx_pool_cleanup_add() may fail too, but this case is
intentionally left out for now as it's almost impossible and proper fix
will require changes to http ssl and mail ssl code as well.
Previously, upstream's status code was overwritten with
cached response's status code when STALE or REVALIDATED
response was sent to the client.
Signed-off-by: Piotr Sikora <piotr@cloudflare.com>
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.
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.
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.
The parameter is mostly identical to http_404, and is expected to
be used in similar situations. The 403 code might be returned by
a backend instead of 404 on initial sync of new directories with rsync.
See here for feature request and additional details:
http://mailman.nginx.org/pipermail/nginx-ru/2013-April/050920.html
The $proxy_internal_body_length value might change during request lifetime,
notably if proxy_set_body used, and use of a cached value might result in
incorrect upstream requests.
Patch by Lanshun Zhou.
This allows to proxy WebSockets by using configuration like this:
location /chat/ {
proxy_pass http://backend;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection "upgrade";
}
Connection upgrade is allowed as long as it was requested by a client
via the Upgrade request header.
Before the patch if proxy_method was specified at http{} level the code
to add trailing space wasn't executed, resulting in incorrect requests
to upstream.
The "proxy_bind", "fastcgi_bind", "uwsgi_bind", "scgi_bind" and
"memcached_bind" directives are now inherited; inherited value
can be reset by the "off" parameter. Duplicate directives are
now detected. Parameter value can now contain variables.
The proxy module context may be NULL in case of filter finalization
(e.g. by image_filter) followed by an internal redirect. This needs
some better handling, but for now just check if ctx is still here.
This resulted in a disclosure of previously freed memory if upstream
server returned specially crafted response, potentially exposing
sensitive information.
Reported by Matthew Daley.
