As per RFC 9204, section 3.2.2, a new entry can reference an entry in the
dynamic table that will be evicted when adding this new entry into the dynamic
table.
Previously, such inserts resulted in use-after-free since the old entry was
evicted before the insertion (ticket #2431). Now it's evicted after the
insertion.
This change fixes Insert with Name Reference and Duplicate encoder instructions.
Ports difference must be respected when checking addresses for duplicates,
otherwise configurations like this are broken:
listen 127.0.0.1:6000-6005
It was broken by 4cc2bfeff46c (nginx 1.23.3).
Fixed event flags handling edge cases in ngx_wsarecv() and ngx_wsarecv_chain(),
notably to always reset rev->ready in case of errors (which wasn't the case
after ngx_socket_nread() errors), and after EOF (rev->ready was not cleared
if due to a misconfiguration a zero-sized buffer was used for reading).
With this change, behaviour of ngx_ssl_recv() now matches ngx_unix_recv(),
which used to always reset c->read->ready to 0 when returning errors.
This fixes an infinite loop in unbuffered SSL proxying if writing to the
client is blocked and an SSL error happens (ticket #2418).
With this change, the fix for a similar issue in the stream module
(6868:ee3645078759), which used a different approach of explicitly
testing c->read->error instead, is no longer needed and was reverted.
Casts are believed to be not needed, since memcmp() has "const void *"
arguments since introduction of the "void" type in C89. And on pre-C89
platforms nginx is unlikely to compile without warnings anyway, as there
are no casts in memcpy() and memmove() calls.
These casts were added in 1648:89a47f19b9ec without any details on why they
were added, and Igor does not remember details either. The most plausible
explanation is that they were copied from ngx_strcmp() and were not really
needed even at that time.
Prodded by Alejandro Colomar.
Binary upgrades are not supported without master process, but it is,
however, possible, that nginx running with master process is asked
to upgrade binary, and the configuration file as available on disk
at this time includes "master_process off;".
If this happens, listening sockets inherited from the previous binary
will have ls[i].previous set. But the old cycle on initial process
startup, including startup after binary upgrade, is destroyed by
ngx_init_cycle() once configuration parsing is complete. As a result,
an attempt to dereference ls[i].previous in ngx_event_process_init()
accesses already freed memory.
Fix is to avoid looking into ls[i].previous if the old cycle is already
freed.
With this change it is also no longer needed to clear ls[i].previous in
worker processes, so the relevant code was removed.
Cloning of listening sockets for each worker process does not make sense
when working without master process, and causes some of the connections
not to be accepted if worker_processes is set to more than one and there
are listening sockets configured with the reuseport flag. Fix is to
disable cloning when master process is disabled.
Due to the glibc bug[1], getaddrinfo("localhost") with AI_ADDRCONFIG
on a typical host with glibc and without IPv6 returns two 127.0.0.1
addresses, and therefore "listen localhost:80;" used to result in
"duplicate ... address and port pair" after 4f9b72a229c1.
Fix is to explicitly filter out duplicate addresses returned during
resolution of a name.
[1] https://sourceware.org/bugzilla/show_bug.cgi?id=14969
Previously, if an event was posted by a read event handler, called by
ngx_close_idle_connections(), that event was not processed until the next
event loop iteration, which could happen after a timeout.
As the SSI parser always uses the context from the main request for storing
variables and blocks, that context should always exist for subrequests using
SSI, even though the main request does not necessarily have SSI enabled.
However, `ngx_http_get_module_ctx(r->main, ...)` is getting NULL in such cases,
resulting in the worker crashing SIGSEGV when accessing its attributes.
This patch links the first initialized context to the main request, and
upgrades it only when main context is initialized.
The check is not expected to fail unless there is a bug in the calling
code. But given the check is here, it should log an alert if it fails
instead of silently closing the connection.
Maximum size for reading the PROXY protocol header is increased to 4096 to
accommodate a bigger number of TLVs, which are supported since cca4c8a715de.
Maximum size for writing the PROXY protocol header is not changed since only
version 1 is currently supported.
Previously, keepalive timer was deleted in ngx_http_v3_wait_request_handler()
and set in request cleanup handler. This worked for HTTP/3 connections, but not
for hq connections. Now keepalive timer is deleted in
ngx_http_v3_init_request_stream() and set in connection cleanup handler,
which works both for HTTP/3 and hq.
It's called after handshake completion or prior to the first early data stream
creation. The callback should initialize application-level data before
creating streams.
HTTP/3 callback implementation sets keepalive timer and sends SETTINGS.
Also, this allows to limit max handshake time in ngx_http_v3_init_stream().
Most atoms should not appear more than once in a container. Previously,
this was not enforced by the module, which could result in worker process
crash, memory corruption and disclosure.
Now it properly detects invalid shared zone configuration with omitted size.
Previously it used to read outside of the buffer boundary.
Found with AddressSanitizer.
OpenSSL with TLSv1.3 updates the session creation time on session
resumption and keeps the session timeout unmodified, making it possible
to maintain the session forever, bypassing client certificate expiration
and revocation. To make sure session timeouts are actually used, we
now update the session creation time and reduce the session timeout
accordingly.
BoringSSL with TLSv1.3 ignores configured session timeouts and uses a
hardcoded timeout instead, 7 days. So we update session timeout to
the configured value as soon as a session is created.
Instead of syncing keys with shared memory on each ticket operation,
the code now does this only when the worker is going to change expiration
of the current key, or going to switch to a new key: that is, usually
at most once per second.
To do so without races, the code maintains 3 keys: current, previous,
and next. If a worker will switch to the next key earlier, other workers
will still be able to decrypt new tickets, since they will be encrypted
with the next key.
As long as ssl_session_cache in shared memory is configured, session ticket
keys are now automatically generated in shared memory, and rotated
periodically. This can be beneficial from forward secrecy point of view,
and also avoids increased CPU usage after configuration reloads.
This also helps BoringSSL to properly resume sessions in configurations
with multiple worker processes and no ssl_session_ticket_key directives,
as BoringSSL tries to automatically rotate session ticket keys and does
this independently in different worker processes, thus breaking session
resumption between worker processes.
Given the present typical SSL session sizes, on 32-bit platforms it is
now beneficial to store all data in a single allocation, since rbtree
node + session id + ASN1 representation of a session takes 256 bytes of
shared memory (36 + 32 + 150 = about 218 bytes plus SNI server name).
Storing all data in a single allocation is beneficial for SNI names up to
about 40 characters long and makes it possible to store about 4000 sessions
in one megabyte (instead of about 3000 sessions now). This also slightly
simplifies the code.
Session ids are not expected to be longer than 32 bytes, but this is
theoretically possible with TLSv1.3, where session ids are essentially
arbitrary and sent as session tickets. Since on 64-bit platforms we
use fixed 32-byte buffer for session ids, added an explicit length check
to make sure the buffer is large enough.
Session cache allocations might fail as long as the new session is different
in size from the one least recently used (and freed when the first allocation
fails). In particular, it might not be possible to allocate space for
sessions with client certificates, since they are noticeably bigger than
normal sessions.
To ensure such allocation failures won't clutter logs, logging level changed
to "warn", and logging is now limited to at most one warning per second.
OpenSSL tries to save TLSv1.3 sessions into session cache even when using
tickets for stateless session resumption, "because some applications just
want to know about the creation of a session". To avoid trashing session
cache with useless data, we do not save such sessions now.
The variables have prefix $proxy_protocol_tlv_ and are accessible by name
and by type. Examples are: $proxy_protocol_tlv_0x01, $proxy_protocol_tlv_alpn.
Previously, all received user input was logged. If a multi-line text was
received from client and logged, it could reduce log readability and also make
it harder to parse nginx log by scripts. The change brings to PROXY protocol
the same behavior that exists for HTTP request line in
ngx_http_log_error_handler().
SSL_sendfile() expects integer file descriptor as an argument, but nginx
uses OS file handles (HANDLE) to work with files on Windows, and passing
HANDLE instead of an integer correctly results in build failure. Since
SSL_sendfile() is not expected to work on Windows anyway, the code is now
disabled on Windows with appropriate compile-time checks.
