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.
Missed during introduction of the SMTP pipelining support (04e43d03e153,
1.5.6). Previously, the check wasn't needed as s->buffer was used directly
and the number of arguments didn't matter.
Reported by Svyatoslav Nikolsky.
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.
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>
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.
