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Crypt::SSLeay.3pm

NAME

Crypt::SSLeay - OpenSSL support for LWP

SYNOPSIS

   lwp-request https://www.example.com
 
   use LWP::UserAgent;
   my $ua  = LWP::UserAgent->new;
   my $req = HTTP::Request->new('GET', 'https://www.example.com/');
   my $res = $ua->request($req);
   print $res->content, "\n";
 
 

DESCRIPTION

This document describes "Crypt::SSLeay" version 0.57, released 2007-09-17.

This perl module provides support for the https protocol under LWP, to allow an "LWP::UserAgent" object to perform GET, HEAD and POST requests. Please see LWP for more information on POST requests.

The "Crypt::SSLeay" package provides "Net::SSL", which is loaded by "LWP::Protocol::https" for https requests and provides the necessary SSL glue.

This distribution also makes following deprecated modules available:

   Crypt::SSLeay::CTX
   Crypt::SSLeay::Conn
   Crypt::SSLeay::X509
 
 

Work on Crypt::SSLeay has been continued only to provide https support for the LWP (libwww-perl) libraries.

ENVIRONMENT VARIABLES

The following environment variables change the way "Crypt::SSLeay" and "Net::SSL" behave.

   # proxy support
   $ENV{HTTPS_PROXY} = 'http://proxy_hostname_or_ip:port';
 
   # proxy_basic_auth
   $ENV{HTTPS_PROXY_USERNAME} = 'username';
   $ENV{HTTPS_PROXY_PASSWORD} = 'password';  
 
   # debugging (SSL diagnostics)
   $ENV{HTTPS_DEBUG} = 1;
 
   # default ssl version
   $ENV{HTTPS_VERSION} = '3';
 
   # client certificate support
   $ENV{HTTPS_CERT_FILE} = 'certs/notacacert.pem';
   $ENV{HTTPS_KEY_FILE}  = 'certs/notacakeynopass.pem';
 
   # CA cert peer verification
   $ENV{HTTPS_CA_FILE}   = 'certs/ca-bundle.crt';
   $ENV{HTTPS_CA_DIR}    = 'certs/';
 
   # Client PKCS12 cert support
   $ENV{HTTPS_PKCS12_FILE}     = 'certs/pkcs12.pkcs12';
   $ENV{HTTPS_PKCS12_PASSWORD} = 'PKCS12_PASSWORD';
 
 

INSTALL

OpenSSL

You must have OpenSSL or SSLeay installed before compiling this module. You can get the latest OpenSSL package from:

   http://www.openssl.org/
 
 

On Debian systems, you will need to install the libssl-dev package, at least for the duration of the build (it may be removed afterwards).

Other package-based systems may require something similar. The key is that Crypt::SSLeay makes calls to the OpenSSL library, and how to do so is specified in the C header files that come with the library. Some systems break out the header files into a separate package from that of the libraries. Once the program has been built, you don't need the headers any more.

When installing openssl make sure your config looks like:

   ./config --openssldir=/usr/local/openssl
  or
   ./config --openssldir=/usr/local/ssl
 
 

If you are planning on upgrading the default OpenSSL libraries on a system like RedHat, (not recommended), then try something like:

   ./config --openssldir=/usr --shared
 
 

The --shared option to config will set up building the .so shared libraries which is important for such systems. This is followed by:

   make
   make test
   make install
 
 

This way Crypt::SSLeay will pick up the includes and libraries automatically. If your includes end up going into a separate directory like /usr/local/include, then you may need to symlink /usr/local/openssl/include to /usr/local/include

Crypt::SSLeay

The latest Crypt::SSLeay can be found at your nearest CPAN, as well as:

   http://search.cpan.org/dist/Crypt-SSLeay/
 
 

Once you have downloaded it, Crypt::SSLeay installs easily using the "make" * commands as shown below.

   perl Makefile.PL
   make
   make test
   make install
 
   * use nmake or dmake on Win32
 
 

For unattended (batch) installations, to be absolutely certain that Makefile.PL does not prompt for questions on STDIN, set the following environment variable beforehand:

   PERL_MM_USE_DEFAULT=1
 
 

(This is true for any CPAN module that uses "ExtUtils::MakeMaker").

Windows

"Crypt::SSLeay" builds correctly with Strawberry Perl.

For Activestate users, the ActiveState company does not have a permit from the Canadian Federal Government to distribute cryptographic software. This prevents "Crypt::SSLeay" from being distributed as a PPM package from their repository. See http://aspn.activestate.com/ASPN/docs/ActivePerl/5.8/faq/ActivePerl-faq2.html#crypto_packages <http://aspn.activestate.com/ASPN/docs/ActivePerl/5.8/faq/ActivePerl-faq2.html#crypto_packages> for more information on this issue.

You may download it from Randy Kobes's PPM repository by using the following command:

   ppm install http://theoryx5.uwinnipeg.ca/ppms/Crypt-SSLeay.ppd
 
 

An alternative is to add the uwinnipeg.ca PPM repository to your local installation. See <http://cpan.uwinnipeg.ca/htdocs/faqs/ppm.html> for more details.

VMS

It is assumed that the OpenSSL installation is located at "/ssl$root". Define this logical to point to the appropriate place in the filesystem.

PROXY SUPPORT

LWP::UserAgent and Crypt::SSLeay have their own versions of proxy support. Please read these sections to see which one is appropriate.

LWP::UserAgent proxy support

LWP::UserAgent has its own methods of proxying which may work for you and is likely to be incompatible with Crypt::SSLeay proxy support. To use LWP::UserAgent proxy support, try something like:

   my $ua = new LWP::UserAgent;
   $ua->proxy([qw( https http )], "$proxy_ip:$proxy_port");
 
 

At the time of this writing, libwww v5.6 seems to proxy https requests fine with an Apache mod_proxy server. It sends a line like:

   GET https://www.example.com HTTP/1.1
 
 

to the proxy server, which is not the CONNECT request that some proxies would expect, so this may not work with other proxy servers than mod_proxy. The CONNECT method is used by Crypt::SSLeay's internal proxy support.

Crypt::SSLeay proxy support

For native Crypt::SSLeay proxy support of https requests, you need to set the environment variable "HTTPS_PROXY" to your proxy server and port, as in:

   # proxy support
   $ENV{HTTPS_PROXY} = 'http://proxy_hostname_or_ip:port';
   $ENV{HTTPS_PROXY} = '127.0.0.1:8080';
 
 

Use of the "HTTPS_PROXY" environment variable in this way is similar to "LWP::UserAgent-"env_proxy()> usage, but calling that method will likely override or break the Crypt::SSLeay support, so do not mix the two.

Basic auth credentials to the proxy server can be provided this way:

   # proxy_basic_auth
   $ENV{HTTPS_PROXY_USERNAME} = 'username';
   $ENV{HTTPS_PROXY_PASSWORD} = 'password';
 
 

For an example of LWP scripting with "Crypt::SSLeay" native proxy support, please look at the eg/lwp-ssl-test script in the "Crypt::SSLeay" distribution.

CLIENT CERTIFICATE SUPPORT

Client certificates are supported. PEM0encoded certificate and private key files may be used like this:

   $ENV{HTTPS_CERT_FILE} = 'certs/notacacert.pem';
   $ENV{HTTPS_KEY_FILE}  = 'certs/notacakeynopass.pem';
 
 

You may test your files with the eg/net-ssl-test program, bundled with the distribution, by issuing a command like:

   perl eg/net-ssl-test -cert=certs/notacacert.pem \
     -key=certs/notacakeynopass.pem -d GET $HOST_NAME
 
 

Additionally, if you would like to tell the client where the CA file is, you may set these.

   $ENV{HTTPS_CA_FILE} = "some_file";
   $ENV{HTTPS_CA_DIR}  = "some_dir";
 
 

There is no sample CA cert file at this time for testing, but you may configure eg/net-ssl-test to use your CA cert with the -CAfile option. (TODO: then what is the ./certs directory in the distribution?)

Creating a test certificate

To create simple test certificates with OpenSSL, you may run the following command:

   openssl req -config /usr/local/openssl/openssl.cnf \
     -new -days 365 -newkey rsa:1024 -x509 \
     -keyout notacakey.pem -out notacacert.pem
 
 

To remove the pass phrase from the key file, run:

   openssl rsa -in notacakey.pem -out notacakeynopass.pem
 
 

PKCS12 support

The directives for enabling use of PKCS12 certificates is:

   $ENV{HTTPS_PKCS12_FILE}     = 'certs/pkcs12.pkcs12';
   $ENV{HTTPS_PKCS12_PASSWORD} = 'PKCS12_PASSWORD';
 
 

Use of this type of certificate takes precedence over previous certificate settings described. (TODO: unclear? Meaning "the presence of this type of certificate??)

SSL versions

Crypt::SSLeay tries very hard to connect to any SSL web server accomodating servers that are buggy, old or simply not standards-compliant. To this effect, this module will try SSL connections in this order:

   SSL v23 - should allow v2 and v3 servers to pick their best type
   SSL v3  - best connection type
   SSL v2  - old connection type
 
 

Unfortunately, some servers seem not to handle a reconnect to SSL v3 after a failed connect of SSL v23 is tried, so you may set before using LWP or Net::SSL:

   $ENV{HTTPS_VERSION} = 3;
 
 

to force a version 3 SSL connection first. At this time only a version 2 SSL connection will be tried after this, as the connection attempt order remains unchanged by this setting.

ACKNOWLEDGEMENTS

Many thanks to Gisle Aas for writing this module and many others including libwww, for perl. The web will never be the same :)

Ben Laurie deserves kudos for his excellent patches for better error handling, SSL information inspection, and random seeding.

Thanks to Dongqiang Bai for host name resolution fix when using a proxy.

Thanks to Stuart Horner of Core Communications, Inc. who found the need for building --shared OpenSSL libraries.

Thanks to Pavel Hlavnicka for a patch for freeing memory when using a pkcs12 file, and for inspiring more robust read() behavior.

James Woodyatt is a champ for finding a ridiculous memory leak that has been the bane of many a Crypt::SSLeay user.

Thanks to Bryan Hart for his patch adding proxy support, and thanks to Tobias Manthey for submitting another approach.

Thanks to Alex Rhomberg for Alpha linux ccc patch.

Thanks to Tobias Manthey for his patches for client certificate support.

Thanks to Daisuke Kuroda for adding PKCS12 certificate support.

Thanks to Gamid Isayev for CA cert support and insights into error messaging.

Thanks to Jeff Long for working through a tricky CA cert SSLClientVerify issue.

Thanks to Chip Turner for patch to build under perl 5.8.0.

Thanks to Joshua Chamas for the time he spent maintaining the module.

Thanks to Jeff Lavallee for help with alarms on read failures (CPAN bug #12444).

Thanks to Guenter Knauf for significant improvements in configuring things in Win32 and Netware lands and Jan Dubois for various suggestions for improvements.

SEE ALSO

Net::SSL

If you have downloaded this distribution as of a dependency of another distribution, it's probably due to this module (which is included in this distribution).

Net::SSLeay

A module that offers access to the OpenSSL API directly from Perl.

   http://search.cpan.org/dist/Net_SSLeay.pm/
 
 

http://www.openssl.org/related/binaries.html

Pointers on where to find OpenSSL binary packages (Windows).

SUPPORT

For use of Crypt::SSLeay & Net::SSL with perl's LWP, please send email to "libwww@perl.org".

For OpenSSL or general SSL support please email the openssl user mailing list at "openssl-users@openssl.org". This includes issues associated with building and installing OpenSSL on one's system.

Please report all bugs at http://rt.cpan.org/NoAuth/Bugs.html?Dist=Crypt-SSLeay <http://rt.cpan.org/NoAuth/Bugs.html?Dist=Crypt-SSLeay>.

This module was originally written by Gisle Aas, and was subsequently maintained by Joshua Chamas. It is currently maintained by David Landgren.

COPYRIGHT

  Copyright (c) 2006-2007 David Landgren.
  Copyright (c) 1999-2003 Joshua Chamas.
  Copyright (c) 1998 Gisle Aas.
 
 

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.