1See documentation.
2Following are some common errors to watch out for:
3
4
5It doesn't work together with Storable::fd_retrieve|fd_store, see
6https://rt.cpan.org/Ticket/Display.html?id=23419.
7You need to use freeze/nfreeze/thaw and syswrite/sysread the data
8yourself. See the bug for examples how to do it.
9
10---------------------
11
12If you get an SSL connection but not certificate you might check
13the cipher with Net::SSLeay::get_cipher( $socket->_get_ssl_object ).
14If it is something like 'ADH-AES256-SHA' you should try to disable
15ADH in your cipherlist, e.g. set SSL_cipherlist to 'ALL:!ADH'
16or just leave it empty so that it uses the openssl default
17which does not include ADH.
18
19---------------------
20
21There is a problem with openssl versions 0.9.8a and 0.9.8b, see
22http://marc.theaimsgroup.com/?l=openssl-dev&m=113550694922967&w=2
23The bug was fixed in newer releases, but if you are forced to use 
24these buggy versions you should apply a patch to Net::SSLeay 1.30,
25see http://rt.cpan.org/Public/Bug/Display.html?id=22910.
26
27---------------------
28
29IO::Socket::SSL does not currently support using both IPv4 and IPv6 in
30the same program.  For a quick workaround, copy the module 'SSL.pm' to
31another named 'SSL6.pm' and adjust the package declaration
32accordingly.  Support for this feature is planned in the next release.
33
34---------------------
35
36If you plan on having IO::Socket::SSL sockets auto-close themselves
37when they go out of scope (like LWP::UserAgent expects), you will
38need to get Scalar::Util or WeakRef from CPAN (Scalar::Util comes
39standard with Perl 5.8.0 and above).  This is because the self-tying
40mechanism that IO::Socket::SSL uses to appear simultaneously as an
41object and a glob reference only works if a circular reference is
42used.
43
44---------------------
45
46Note that a random number generator is required for the proper
47operation of this module.  Systems that have /dev/random or
48/dev/urandom are fine, but those that do not, like most versions
49of Solaris, will need to fetch one before installing IO::Socket::SSL.
50If you don't already have a favorite, try EGD (egd.sourceforge.net).
51
52---------------------
53
54Versions of perl-ldap below v0.26 do not work with this version
55of IO::Socket::SSL because they contain a workaround for old
56versions of IO::Socket::SSL that breaks new versions.
57
58---------------------
59
60Note that when writing a preforking server (a server that accepts a
61connection and then hands it off to a child for processing), it is
62best to handle SSL negotiation after the socket has been passed to
63the child (using socket_to_SSL()).  If implemented so that the server
64handles negotiation, a failed negotiation may tie up the server until
65the connection times out.
66
67---------------------
68
69One user mentioned that the following did not work as it should in
70IO::Socket::SSL, but worked in IO::Socket::INET:
71
72chomp($var = <$socket>);
73print ord(chop($var));    # Prints "10" for people using ASCII
74
75This is due to a bug in Perl that is fixed in 5.8.1.  If you need
76a workaround, try one of the following:
77
78chomp($var = $socket->getline());
79chomp($var = scalar <$socket>);
80chomp($var = $var = <$socket>);
81
82Any function that returns the value of <$socket> (in scalar context)
83unchanged will work.
84
85---------------------
86
87If you have 384-bit RSA keys you need to use Diffie Hellman Key Exchange.
88See the parameter SSL_dh_file or SSL_dh for how to use it and
89http://groups.google.de/group/mailing.openssl.users/msg/d60330cfa7a6034b
90for an explanation why you need it.
91
92-- 
93Peter Behroozi (behrooz at fas.harvard.edu)
94Steffen Ullrich (Steffen_Ullrich at genua.de)
95