macosx.html   [plain text]


<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
  <title>Building and Using Cyrus SASL on Mac OS X</title>
<!-- $Id: macosx.html,v 1.6 2006/01/20 20:15:07 snsimon Exp $ -->
</head>
<body>
<h1>Cyrus SASL v2 on Mac OS X (and 9)</h1>
<p>The Cyrus SASL v2 distribution now supports Mac OS X, including
applications written to Apple's Carbon and Cocoa interfaces, as well
as the standard Unix-like API. It includes the following
components:</p>
<ul>
  <li>A port of the Unix SASL library, which lives in <tt>/usr/local/lib/libsasl2.dylib</tt>
(or something like that) and
with plugins in <tt>/usr/lib/sasl</tt> (which should be a symlink to <tt>/usr/local/lib/sasl</tt>).
  </li>
  <li>A framework which lives in
<tt>/Library/Frameworks/SASL2.framework</tt>, and allows the use of the
<tt>-framework</tt> option to Apple's <tt>ld</tt>, or linking with the
framework in Project Builder. This framework is in fact a wrapper for a
symlink to <tt>/usr/local/lib/libsasl2.dylib</tt> with the necessary
information to recognize it as a framework. This is what we expect many
Cocoa and Carbon Mach-O applications will want to use, and the framework
is required for CFBundle to work, which is used by the CFM glue library.
</li>
  <li>A CFM glue library (<tt>/Library/CFMSupport/SASL2GlueCFM</tt>) which
can be linked in by Carbon CFM applications, that uses CFBundle to bind
the framework and thus load the Unix-level library. It automatically loads
the important functions at <tt>sasl_client_init</tt> or
<tt>sasl_server_init</tt> time; it also automatically makes sure memory
allocation works if you're using the metrowerks malloc; if you're not,
<tt>sasl_set_alloc</tt> works as usual. </li>
  <li>A Carbon port of the existing CFM library for Mac OS 9. Note that
this could probably be modified fairly easily to work on OS X, but
there's not much point. The CFM glue layer to the Unix library
supports many more functions, including the entire server API; also,
the Unix implementation is mostly independent of Kerberos
implementation, while the Mac OS 9 Carbon port specifically requires
MIT Kerberos for Macintosh 3.5 or later in order to get Kerberos
support. The Mac OS 9 code implements only the client API, but this is
mostly what is wanted from SASL on OS 9 anyway. </li>
</ul>
<p>If you are building a Carbon CFM application and intend it to run on
both OS 9 and OS X, you should link against the OS 9 Carbon SASL
library, since it exports fewer APIs (client side only, specifically)
than the OS X CFM glue. Your application should work seamlessly with
both libraries if you do this, despite the different implementations
underneath.</p>
<p>If you need a Carbon CFM application to support server-side SASL
functionality, you need to link against the <tt>SASL2GlueCFM</tt>
library, but be aware that your application will not run on OS 9.</p>
<h2>Compiling and Using the Unix library</h2>

The Unix library is mostly ready to build on Mac OS X, but it does depend
on the <tt>dlcompat</tt> package in order to load its plugins.
<tt>dlcompat-20010505</tt> is a relatively simple version known to work
with SASL; it is provided with the distribution in a tarball. You should
<tt>make</tt> and <tt>make install</tt> the <tt>dlcompat</tt> library
(which probably goes into <tt>/usr/local/lib/libdl.dylib</tt>) before
attempting to <tt>./configure</tt> the SASL distribution itself. SASL will
then pretend it's a real Unix <tt>libdl</tt>, and link against it. 

<p>Since there are, at this point, newer and far more complex versions of
dlcompat, you may prefer to use those instead if other software requires
their functionality. The dlcompat homepage is located <a
href="http://www.opendarwin.org/projects/dlcompat/">on the OpenDarwin
site.</a> Many users may want to install the <tt>/sw</tt> tree from <a
href="http://fink.sourceforge.net/">the Fink project</a> to get this, as
well as possibly newer autotools and other software.<br> </p>

<p>As of version 2.1.16, SASL uses and requires a recent version of GNU
autotools (autoconf, automake, and libtool) to build its configuration scripts.
If you are building from CVS, you will need to have the autotools installed
on your system. The version included with all releases of the developer tools
for OS X 10.2.x is too old for this; if you aren't using OS X 10.3 or later,
you should upgrade to more recent patchlevels of these tools. The easiest way
to do this is to <a href="http://fink.sourceforge.net/">install the Fink
environment</a> and then <tt>apt-get
install autoconf2.5 automake1.7 libtool14</tt>.<br>
</p>
<p>Recent versions of SASL ship with Kerberos v4 disabled by default.
If you need Kerberos v4 for some reason, and you are using MIT Kerberos
for Macintosh 4.0 or later, you should <tt>./configure</tt> with
the added options <tt>"--enable-krb4=/usr --without-openssl
--disable-digest"</tt> so that it finds the
correct location for the header files, and does not use OpenSSL or
build anything that depends on it (such as the digest-md5 plugin),
since OpenSSL provides its own DES routines which do not work with
Kerberos v4. <i>Please read the "Known Problems" section at the end of
this
document for more information on this issue.<br>
</i></p>
<p>You must be root to make install, since <tt>/usr/local</tt> is only
modifiable by root. You need not enable the root account using
NetInfo; the recommended (but underdocumented) method is to use
<tt>sudo -s</tt> from the Terminal window when you are logged into an
administrator's account, and enter the password for that account. When
building on Mac OS X, <tt>make install</tt> will automatically add the
framework to <tt>/Library/Frameworks</tt>.</p>
<p>This does not build the CFM glue library. Building the CFM glue
library requires Metrowerks CodeWarrior Pro 6 or later (tested with
6), and the files necessary to build it are in the
<tt>mac/osx_cfm_glue</tt> folder.</p>
<h2>Changes to the Unix library to make it work on OS X</h2>
<p>This is provided for reference purposes only. The build system will
automatically take care of all of these issues when building on Darwin
or Mac OS X.</p>
<ul>
  <li>The random code supports the preferred way to generate random
numbers in Darwin. (In SASL v2, it does this on all unix-like
platforms that lack jrand48). <i>Note that Mac OS X "Jaguar", version
10.2,
now has the standard jrand48 function, and that SASL will use this
instead
of the previous workaround.</i> </li>
  <li>Symbols which are dlopened have an underscore prefixed. (This
behavior is detected by configure in SASL v2.) </li>
  <li>Plugins are linked with the <tt>-module</tt> option to <tt>libtool</tt>,
which causes the <tt>-bundle</tt> option to be
supplied to Apple's <tt>ld</tt>. (This is done on all platforms in
SASL v2.) </li>
  <li>The MD5 symbols are renamed to avoid library conflicts. This
allows proper compilations against Heimdal and MIT's unix kerberos
distribution, and prevents crashes when linked against MIT Kerberos
for Macintosh (which also duplicates the symbols, but in a different
way). Note that the MD5 symbols have local names on all platforms with
SASL v2; this was only different in SASL v1. </li>
  <li>MIT Kerberos for Macintosh 4.0 and later are fully supported. This
was accomplished by using <tt>krb_get_err_text</tt> if available and
checking for additional names for the krb4 libraries. </li> </ul>
<h2>Changes to the Mac OS 9 projects to support Carbon</h2>
<p><b><i>Please read these notes before you attempt to build SASL for OS 9
Carbon!</i></b> </p> <ul>
  <li><b>Important!</b> You must make sure that all files have their
correct HFS filetype before starting to build this code! In
particular, all source and text files must be of type <tt>'TEXT'</tt>,
which is not the default if you use the Mac OS X cvs client to check
out the projects. If you run into this problem, you may want to use a
utility such as FileTyper to recursively change the type on all
files. CodeWarrior is less picky about the projects' filetypes, but
setting them to filetype <tt>'MMPr'</tt>, creator code <tt>'CWIE'</tt>
may be helpful in opening the projects from the Finder. Users on Mac OS
X familiar with the Unix <tt>find</tt>
command should be able to rig <tt>/Developer/Tools/SetFile</tt>
to do this job as well. </li>
  <li>Many of the important projects (for <tt>libdes</tt>, <tt>libsasl</tt>,
    <tt>build_plugins</tt>, and the sample client <tt>sc_shlb</tt>)
have Carbon versions. </li>
  <li>Plugins are loaded from a <tt>Carbon</tt> subfolder of the <tt>SASL
v2</tt> folder in the Extensions folder. Plugins directly
in
the <tt>SASL v2</tt> folder are considered to be for the Classic
libraries. </li>
  <li>Note that when using the <tt>build_plugins</tt> project, you must
generate the plugin init files using the <tt>makeinit.sh</tt> script in
the <tt>plugins</tt> directory. The easiest way to do this is to run the
script from a Unix shell, such as Mac OS X. You must then fix the
filetypes of the generated source files (see above). </li>
  <li>There is a new folder in <tt>CommonKClient</tt> called <tt>mac_kclient3</tt>
which contains code compatible with MIT's new <a
 href="http://web.mit.edu/macdev/Development/MITKerberos/MITKerberosLib/KClient/Documentation/index.html">KClient
3.0</a> API. This folder must be in your CodeWarrior access paths, the
old <tt>mac_kclient</tt> folder must not, and it must precede the
project's main folder. </li>
  <li>The kerberos4 plugin uses this new code. The kerberos4 plugin
also
statically links the Carbon <tt>libdes</tt>, and no other part of
Carbon SASL uses <tt>libdes</tt> directly. <i>Your application should
    <b>not</b> link against</i> <tt>libdes.shlb</tt> <i>under Carbon!</i>
(It causes problems due to DES symbols also existing in the MIT
Kerberos library, which loads first.) </li>
  <li>To build the projects, you should have the MIT Kerberos for
Macintosh 3.5 installation disk images mounted, since the access paths
include the absolute paths to the library directories from that
image. It's easier than you having to find the paths yourself, and
smaller than having to distribute the libraries with SASL. </li>
</ul>
<h2>Known Problems</h2>
<ul>
  <li>The Kerberos v4 headers bundled with Mac OS X (and Kerberos for
Macintosh) are not compatible with OS X's OpenSSL headers. (Kerberos v4
support is disabled by default.) If you actually need krb4 support, the
easiest solution is to build without using OpenSSL's
<tt>libcrypto</tt>. To do this, specify the <tt>--without-openssl</tt>
option to <tt>configure</tt>. As of version 2.1.18, this automatically
disables using <tt>libcrypto</tt> for DES as well. You will probably
also need to specify <tt>--disable-digest</tt> since the digestmd5 plugin
does not build against Kerberos v4's DES headers or library. Note that
this disables several features (digestmd5, NTLM, OTP) which require
OpenSSL. If both Kerberos v4 and functionality that requires OpenSSL are
needed, it is probably possible to build the Kerberos v4 plugin against
the correct K4 DES libraries, and everything else against OpenSSL;
however, we do not support that configuration.<br>
  </li>
  <li>Versions of Cyrus SASL prior to 2.1.14 with support for Carbon
CFM applications on Mac OS X have a known bug involving the CFM glue
code (in <tt>mac/osx_cfm_glue</tt>). If <tt>sasl_done</tt> is called
to unload the SASL library, and then one of the initialization
functions (such as <tt>sasl_client_init</tt>) is called to
reinitialize it from the same process, the application will crash. A
fix for one obvious cause of this problem is included in 2.1.14;
however, as of this writing, it has not been tested. It is possible
that other bugs in Cyrus SASL, or deficiencies in Apple's libraries,
will make this fix insufficient to resolve this issue. </li>
</ul>
</body>
</html>