postgresql

History

Peter Eisentraut c1869542b3 Use abstracted SSL API in server connection log messages The existing "connection authorized" server log messages used OpenSSL API calls directly, even though similar abstracted API calls exist. Change to use the latter instead. Change the function prototype for the functions that return the TLS version and the cipher to return const char * directly instead of copying into a buffer. That makes them slightly easier to use. Add bits= to the message. psql shows that, so we might as well show the same information on the client and server. Reviewed-by: Daniel Gustafsson <daniel@yesql.se> Reviewed-by: Michael Paquier <michael.paquier@gmail.com>		2018-01-26 09:50:46 -05:00
..
Makefile	Support SCRAM-SHA-256 authentication (RFC 5802 and 7677).	2017-03-07 14:25:40 +02:00
README.SSL	Move EDH support to common files	2018-01-23 07:11:38 -05:00
auth-scram.c	Implement channel binding tls-server-end-point for SCRAM	2018-01-04 15:29:50 -05:00
auth.c	Refactor channel binding code to fetch cbind_data only when necessary	2018-01-04 13:55:12 -05:00
be-fsstubs.c	Update copyright for 2018	2018-01-02 23:30:12 -05:00
be-secure-openssl.c	Use abstracted SSL API in server connection log messages	2018-01-26 09:50:46 -05:00
be-secure.c	Extract common bits from OpenSSL implementation	2018-01-23 07:11:39 -05:00
crypt.c	Update copyright for 2018	2018-01-02 23:30:12 -05:00
hba.c	Allow ldaps when using ldap authentication	2018-01-03 10:11:26 -05:00
ifaddr.c	Update copyright for 2018	2018-01-02 23:30:12 -05:00
pg_hba.conf.sample	Rename "scram" to "scram-sha-256" in pg_hba.conf and password_encryption.	2017-04-18 14:50:50 +03:00
pg_ident.conf.sample	Reformat the comments in pg_hba.conf and pg_ident.conf	2010-01-26 06:58:39 +00:00
pqcomm.c	Update copyright for 2018	2018-01-02 23:30:12 -05:00
pqformat.c	Update copyright for 2018	2018-01-02 23:30:12 -05:00
pqmq.c	Update copyright for 2018	2018-01-02 23:30:12 -05:00
pqsignal.c	Update copyright for 2018	2018-01-02 23:30:12 -05:00

README.SSL

src/backend/libpq/README.SSL

SSL
===

>From the servers perspective:


  Receives StartupPacket
           |
           |
 (Is SSL_NEGOTIATE_CODE?) -----------  Normal startup
           |                  No
           |
           | Yes
           |
           |
 (Server compiled with USE_SSL?) ------- Send 'N'
           |                       No        |
           |                                 |
           | Yes                         Normal startup
           |
           |
        Send 'S'
           |
           |
      Establish SSL
           |
           |
      Normal startup





>From the clients perspective (v6.6 client _with_ SSL):


      Connect
         |
         |
  Send packet with SSL_NEGOTIATE_CODE
         |
         |
  Receive single char  ------- 'S' -------- Establish SSL
         |                                       |
         | '<else>'                              |
         |                                  Normal startup
         |
         |
   Is it 'E' for error  ------------------- Retry connection
         |                  Yes             without SSL
         | No
         |
   Is it 'N' for normal ------------------- Normal startup
         |                  Yes
         |
   Fail with unknown

---------------------------------------------------------------------------

Ephemeral DH
============

Since the server static private key ($DataDir/server.key) will
normally be stored unencrypted so that the database backend can
restart automatically, it is important that we select an algorithm
that continues to provide confidentiality even if the attacker has the
server's private key.  Ephemeral DH (EDH) keys provide this and more
(Perfect Forward Secrecy aka PFS).

N.B., the static private key should still be protected to the largest
extent possible, to minimize the risk of impersonations.

Another benefit of EDH is that it allows the backend and clients to
use DSA keys.  DSA keys can only provide digital signatures, not
encryption, and are often acceptable in jurisdictions where RSA keys
are unacceptable.

The downside to EDH is that it makes it impossible to use ssldump(1)
if there's a problem establishing an SSL session.  In this case you'll
need to temporarily disable EDH (see initialize_dh()).