Activated with the "proxy_protocol" parameter of the "listen" directive.
Obtained information is passed to the auth_http script in Proxy-Protocol-Addr,
Proxy-Protocol-Port, Proxy-Protocol-Server-Addr, and Proxy-Protocol-Server-Port
headers.
Similarly to 40e8ce405859 in the stream module, this reduces the time
accept mutex is held. This also simplifies following changes to
introduce PROXY protocol support.
If we need to be notified about further events, ngx_handle_read_event()
needs to be called after a read event is processed. Without this,
an event can be removed from the kernel and won't be reported again,
notably when using oneshot event methods, such as eventport on Solaris.
For consistency, existing ngx_handle_read_event() call removed from
ngx_mail_read_command(), as this call only covers one of the code paths
where ngx_mail_read_command() returns NGX_AGAIN. Instead, appropriate
processing added to the callers, covering all code paths where NGX_AGAIN
is returned.
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.
This fixes segfault in configurations with multiple virtual servers sharing
the same port, where a non-default virtual server block misses certificate.
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.
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 "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.
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).
