When using SMTP with SSL and resolver, read events might be enabled
during address resolving, leading to duplicate ngx_mail_ssl_handshake_handler()
calls if something arrives from the client, and duplicate session
initialization - including starting another resolving. This can lead
to a segmentation fault if the session is closed after first resolving
finished. Fix is to block read events while resolving.
Reported by Robert Norris,
http://mailman.nginx.org/pipermail/nginx/2019-July/058204.html.
Previously only one address was used by the listen directive handler even if
host name resolved to multiple addresses. Now a separate listening socket is
created for each address.
If ngx_pool_cleanup_add() fails, we have to clean just created SSL context
manually, thus appropriate call added.
Additionally, ngx_pool_cleanup_add() moved closer to ngx_ssl_create() in
the ngx_http_ssl_module, to make sure there are no leaks due to intermediate
code.
Dynamic certificates re-introduce problem with incorrect session
reuse (AKA "virtual host confusion", CVE-2014-3616), since there are
no server certificates to generate session id context from.
To prevent this, session id context is now generated from ssl_certificate
directives as specified in the configuration. This approach prevents
incorrect session reuse in most cases, while still allowing sharing
sessions across multiple machines with ssl_session_ticket_key set as
long as configurations are identical.
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.
In 51e1f047d15d, the "ssl" directive name was incorrectly hardcoded
in the error message shown when there are some SSL keys defined, but
not for all certificates. Right approach is to use the "mode" variable,
which can be either "ssl" or "starttls".
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.
In http these checks were changed in a6d6d762c554, though mail module
was missed at that time. Since then, the stream module was introduced
based on mail, using "== NGX_ERROR" check.
Most notably, warning W8012 (comparing signed and unsigned values) reported
in multiple places where an unsigned value of small type (e.g., u_short) is
promoted to an int and compared to an unsigned value.
Warning W8072 (suspicious pointer arithmetic) disabled, it is reported
when we increment base pointer in ngx_shm_alloc().
This is needed to allow TLS client certificate auth to work. With
ssl_verify_client configured, the auth daemon can choose to allow the
connection to proceed based on the certificate data.
This has been tested with Thunderbird for IMAP only. I've not yet found a
client that will do client certificate auth for POP3 or SMTP, and the method is
not really documented anywhere that I can find. That said, its simple enough
that the way I've done is probably right.
The IPV6_V6ONLY macro is now checked only while parsing appropriate flag
and when using the macro.
The ipv6only field in listen structures is always initialized to 1,
even if not supported on a given platform. This is expected to prevent
a module compiled without IPV6_V6ONLY from accidentally creating dual
sockets if loaded into main binary with proper IPV6_V6ONLY support.
All the errors that prevent loading configuration must be printed on the "emerg"
log level. Previously, nginx might silently fail to load configuration in some
cases as the default log level is "error".
This patch moves various OpenSSL-specific function calls into the
OpenSSL module and introduces ngx_ssl_ciphers() to make nginx more
crypto-library-agnostic.
OpenSSL 1.0.2+ allows configuring a curve list instead of a single curve
previously supported. This allows use of different curves depending on
what client supports (as available via the elliptic_curves extension),
and also allows use of different curves in an ECDHE key exchange and
in the ECDSA certificate.
The special value "auto" was introduced (now the default for ssl_ecdh_curve),
which means "use an internal list of curves as available in the OpenSSL
library used". For versions prior to OpenSSL 1.0.2 it maps to "prime256v1"
as previously used. The default in 1.0.2b+ prefers prime256v1 as well
(and X25519 in OpenSSL 1.1.0+).
As client vs. server preference of curves is controlled by the
same option as used for ciphers (SSL_OP_CIPHER_SERVER_PREFERENCE),
the ssl_prefer_server_ciphers directive now controls both.
Resolved warnings about declarations that hide previous local declarations.
Warnings about WSASocketA() being deprecated resolved by explicit use of
WSASocketW() instead of WSASocket(). When compiling without IPv6 support,
WinSock deprecated warnings are disabled to allow use of gethostbyname().
There is no need to set "i" to 0, as it's expected to be 0 assuming
the bindings are properly sorted, and we already rely on this when
explicitly set hport->naddrs to 1. Remaining conditional code is
replaced with identical "hport->naddrs = i + 1".
Identical modifications are done in the mail and stream modules,
in the ngx_mail_optimize_servers() and ngx_stream_optimize_servers()
functions, respectively.
No functional changes.
LibreSSL removed support for export ciphers and a call to
SSL_CTX_set_tmp_rsa_callback() results in an error left in the error
queue. This caused alerts "ignoring stale global SSL error (...called
a function you should not call) while SSL handshaking" on a first connection
in each worker process.
Previously, the Auth-SSL-Verify header with the "NONE" value was always passed
to the auth_http script if verification of client certificates is disabled.
The "ssl_verify_client", "ssl_verify_depth", "ssl_client_certificate",
"ssl_trusted_certificate", and "ssl_crl" directives introduced to control
SSL client certificate verification in mail proxy module.
If there is a certificate, detail of the certificate are passed to
the auth_http script configured via Auth-SSL-Verify, Auth-SSL-Subject,
Auth-SSL-Issuer, Auth-SSL-Serial, Auth-SSL-Fingerprint headers. If
the auth_http_pass_client_cert directive is set, client certificate
in PEM format will be passed in the Auth-SSL-Cert header (urlencoded).
If there is no required certificate provided during an SSL handshake
or certificate verification fails then a protocol-specific error is
returned after the SSL handshake and the connection is closed.
Based on previous work by Sven Peter, Franck Levionnois and Filipe Da Silva.
