Crypt::SSLeay - OpenSSL support for LWP
Synopsis
lwp-request https://www.example.com
use LWP::UserAgent;
my $ua = LWP::UserAgent->new;
my $response = $ua->get('https://www.example.com/');
print $response->content, "\n";
Description
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 Authentication
$ENV{HTTPS_PROXY_USERNAME} = 'username';
$ENV{HTTPS_PROXY_PASSWORD} = 'password';
SSL Diagnostics and Debugging
$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';
Installation
OpenSSL
You must have OpenSSL installed before compiling this module. You can get the latest OpenSSL package from http://www.openssl.org/. We no longer support pre-2000 versions of OpenSSL.
If you are building OpenSSL from source, please follow the directions included in the package.
If you are going to use an OpenSSL library which you built from source or
whose header and library files are not in a place searched by your compiler
by default, make sure you set appropriate environment variables before
trying to build Crypt::SSLeay
.
For example, if you are using ActiveState Perl and MinGW installed using
ppm, and you installed OpenSSL in C:\opt\openssl-1.0.1c
, then you would
issue the following commands to build Crypt::SSLeay
:
C:\temp\Crypt-SSLeay> set LIBRARY_PATH=C:\opt\openssl-1.0.1c\lib;%LIBRARY_PATH%
C:\temp\Crypt-SSLeay> set CPATH=C:\opt\openssl-1.0.1c\include;%CPATH%
C:\temp\Crypt-SSLeay> perl Makefile.PL --live-tests
C:\temp\Crypt-SSLeay> dmake test
On Linux/BSD/Solaris/GNU etc systems, you would use make
rather than
dmake
, but you would need to set the same variables if your OpenSSL
library is in a custom location. If everything builds OK, but you get
failures when during tests, ensure that LD_LIBRARY_PATH
points to the
location where the correct shared libraries are located.
If you are using a Microsoft compiler (keep in mind that perl
and OpenSSL
need to have been built using the same compiler as well), you would use:
C:\temp\Crypt-SSLeay> set LIB=C:\opt\openssl-1.0.1c\lib;%LIB%
C:\temp\Crypt-SSLeay> set INCLUDE=C:\opt\openssl-1.0.1c\include;%INCLUDE%
C:\temp\Crypt-SSLeay> perl Makefile.PL --live-tests
C:\temp\Crypt-SSLeay> nmake test
Depending on your OS, pre-built OpenSSL packages may be available. You may need to install a development version of your operating system's OpenSSL library package. 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.
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
standard build process:
perl Makefile.PL
make
make test
make install
On Windows systems, both Strawberry Perl and ActiveState (as a separate
download via ppm) projects include a MingW based compiler distribution and
dmake which can be used to build both OpenSSL and Crypt::SSLeay
. If you have
such a set up, use dmake above.
Makefile.PL takes two optional arguments:
--live-tests
: Boolean. Specifies whether we should try to connect to an HTTPS URL during testing. Default is false.To skip live tests, you can use
perl Makefile.PL --no-live-tests
and to force live tests, you can use
perl Makefile.PL --live-tests
--static
: Boolean. Default is false. (TODO: Does it work?)
For unattended (batch) installations, to be absolutely certain that
Makefile.PL
does not prompt for questions on STDIN
, set the environment
variable PERL_MM_USE_DEFAULT=1
as with any CPAN module built using
ExtUtils::MakeMaker
.
Windows
Crypt::SSLeay
builds correctly with Strawberry Perl and ActiveState Perl
using the bundled MinGW.
For ActiveState Perl 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://docs.activestate.com/activeperl/5.16/faq/ActivePerl-faq2.html#crypto_packages
for more information on this issue. You may be able to download a PPM for
Crypt::SSLeay
from an alternative repository (see PPM::Repositories
).
VMS
I do not have any experience with VMS. If OpenSSL headers and libraries are not in standard locations searched by your build system by default, please set things up so that they are. If you have generic instructions on how to do it, please open a ticket on RT with the information so I can add it to this document.
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 = LWP::UserAgent->new;
$ua->proxy([qw( https http )], "$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 authentication 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. PEM encoded 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";
Note that, if specified, $ENV{HTTPS_CA_FILE}
must point to the actual
certificate file. That is, $ENV{HTTPS_CA_DIR}
is not the path where
$ENV{HTTPS_CA_FILE}
is located.
For certificates in $ENV{HTTPS_CA_DIR}
to be picked up, follow the
instructions on http://www.openssl.org/docs/ssl/SSL_CTX_load_verify_locations.html.
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 the following individuals who helped improve Crypt-SSLeay:
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.
Dongqiang Bai for host name resolution fix when using a proxy.
Stuart Horner of Core Communications, Inc. who found the need for building
--shared
OpenSSL libraries.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.Bryan Hart for his patch adding proxy support, and thanks to Tobias Manthey for submitting another approach.
Alex Rhomberg for Alpha linux ccc patch.
Tobias Manthey for his patches for client certificate support.
Daisuke Kuroda for adding PKCS12 certificate support.
Gamid Isayev for CA cert support and insights into error messaging.
Jeff Long for working through a tricky CA cert SSLClientVerify issue.
Chip Turner for a patch to build under perl 5.8.0.
Joshua Chamas for the time he spent maintaining the module.
Jeff Lavallee for help with alarms on read failures (CPAN bug #12444).
Guenter Knauf for significant improvements in configuring things in Win32 and Netware lands and Jan Dubois for various suggestions for improvements.
and many others who provided bug reports, suggestions, fixes and patches.
TODO: Update acknowledgements list.
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
Net::SSLeay provides access to the OpenSSL API directly from Perl. See http://search.cpan.org/dist/Net-SSLeay/.
OpenSSL binary packages for Windows, see http://www.openssl.org/related/binaries.html.
Support
For use of
Crypt::SSLeay
&Net::SSL
with Perl's LWP, please send email to libwww@perl.org libwww@perl.org.For OpenSSL or general SSL support, including issues associated with building and installing OpenSSL on your system, please email the OpenSSL users mailing list at openssl-users@openssl.org openssl-users@openssl.org. See http://www.openssl.org/support/community.html for other mailing lists and archives.
Please report all bugs at http://rt.cpan.org/NoAuth/Bugs.html?Dist=Crypt-SSLeay.
Authors
This module was originally written by Gisle Aas, and was subsequently maintained by Joshua Chamas, David Landgren, brian d foy, and A. Sinan Unur.
Copyright
Copyright © 2010-2012 A. Sinan Unur
Copyright © 2006-2007 David Landgren
Copyright © 1999-2003 Joshua Chamas
Copyright © 1998 Gisle Aas
License
this program is free software; you can redistribute it and/or modify it under the terms of Artistic License 2.0. See http://www.perlfoundation.org/artistic_license_2_0.