+++ This bug was initially created as a clone of Bug #1091316 +++
+++ This bug was initially created as a clone of Bug #1090966 +++
+++ This bug was initially created as a clone of Bug #1044401 +++

Description of problem:
LDAPS connection fails with error: "IO::Socket::SSL: SSL connect attempt failed with unknown errorerror:100AE081:elliptic curve routines:EC_GROUP_new_by_curve_name:unknown group"

Version-Release number of selected component (if applicable):
openssl-1.0.1e-15.el6.x86_64
openssl-1.0.1e-16.el6_5.x86_64

How reproducible:
#!/usr/bin/perl                                                                 

sub ldap_query {
        use Net::LDAPS;

        my $conn = Net::LDAPS->new('ldap.example.com',
                                 version => 3,
                                 port => 636,
                                 capath => '/etc/openldap/cacerts/',
                                 raw => qr/^$/
                               ) || die "$@\n";

        $conn->disconnect();
        return 0;
}

my $test = ldap_query();

Steps to Reproduce:
1. Run above script against suitable ldap-server
2.
3.

Actual results:
IO::Socket::SSL: SSL connect attempt failed with unknown errorerror:100AE081:elliptic curve routines:EC_GROUP_new_by_curve_name:unknown group

Expected results:
Empty output

Additional info:
Downgrade to openssl-1.0.0-27.el6_4.2.x86_64 solves the issue.

[...]
--- Additional comment from Tomas Mraz on 2014-04-24 12:55:23 GMT ---

The SSL_version setting is probably no problem. However the ALL cipher list string really should not be used. Either the cipher list should not be set at all or the 'DEFAULT' string could be used.

[...]
--- Additional comment from Petr Pisar on 2014-04-25 07:08:43 GMT ---

How to test:

(1) Start an SSL server.
(2) Run a simple Net::LDAPS client without `ciphers' option against the server.
(3) Compare list of ciphers advertised by the client to the server against DEFAULT OpenSSL list (see `openssl ciphers DEFAULT' command output).
Before:
  The lists differ.
After:
  The lists are identical.

[...]
--- Additional comment from Petr Pisar on 2014-08-06 16:08:46 GMT ---

See bug #1090966 for testing instructions.

However please note that current IO::Socket:SSL Perl module (perl-IO-Socket-SSL-1.94-3.el7.noarch) does not respect OpenSSL defaults and overrides it:

        SSL_cipher_list
          If this option is set the cipher list for the connection will be set
          to the given value, e.g. something like 'ALL:!LOW:!EXP:!ADH'. Look
          into the OpenSSL documentation
          (<http://www.openssl.org/docs/apps/ciphers.html#CIPHER_STRINGS>) for
          more details.

          If this option is not set 'ALL:!LOW' will be used. To use OpenSSL
          builtin default (whatever this is) set it to ''.

This undermines this perl-Net-LDAP fix and causes sneaking some ciphers into Net::LDAP application:

--- default.sorted      2014-08-06 16:36:58.176000000 +0200
+++ fixed.sorted        2014-08-06 16:35:23.573000000 +0200
@@ -1,3 +1,18 @@
+ADH-AES128-GCM-SHA256
+ADH-AES128-SHA
+ADH-AES128-SHA256
+ADH-AES256-GCM-SHA384
+ADH-AES256-SHA
+ADH-AES256-SHA256
+ADH-CAMELLIA128-SHA
+ADH-CAMELLIA256-SHA
+ADH-DES-CBC3-SHA
+ADH-RC4-MD5
+ADH-SEED-SHA
+AECDH-AES128-SHA
+AECDH-AES256-SHA
+AECDH-DES-CBC3-SHA
+AECDH-RC4-SHA
 AES128-GCM-SHA256
 AES128-SHA
 AES128-SHA256
@@ -59,17 +74,15 @@
 ECDH-RSA-RC4-SHA
 EDH-DSS-DES-CBC3-SHA
 EDH-RSA-DES-CBC3-SHA
+EXP-ADH-DES-CBC-SHA
+EXP-ADH-RC4-MD5
+EXP-DES-CBC-SHA
+EXP-EDH-DSS-DES-CBC-SHA
+EXP-EDH-RSA-DES-CBC-SHA
+EXP-RC2-CBC-MD5
+EXP-RC4-MD5
 IDEA-CBC-SHA
-KRB5-DES-CBC3-MD5
-KRB5-DES-CBC3-SHA
-KRB5-IDEA-CBC-MD5
-KRB5-IDEA-CBC-SHA
-KRB5-RC4-MD5
-KRB5-RC4-SHA
- -3DES-EDE-CBC-SHA
-PSK-AES128-CBC-SHA
-PSK-AES256-CBC-SHA
-PSK-RC4-SHA
 RC4-MD5
 RC4-SHA
 SEED-SHA

The erroneous cipher-suites are the ADH and AECDH and EXP ones. I will report bug against perl-IO-Socket-SSL.

(The KRB5 and PSK ones are not present in the Net::LDAP client because no Kerberos, nor PSK TLS authentication has been available when running the client. These misses are fine.)