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<title>Building and Using Cyrus SASL on Mac OS X</title>
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<h1>Cyrus SASL v2 on Mac OS X (and 9)</h1><p>

<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>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.

<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>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.

</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>

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><p>

If you are using MIT Kerberos for Macintosh 4.0 or later, which is fully
supported by the SASL library, you should <tt>./configure</tt> with
the added option <tt>--enable-krb4=/usr</tt> so that it finds the
correct location for the header files. KfM will be automatically
detected by the configure script, and the correct libraries linked
in. <i>Please read the "Known Problems" section at the end of this
document for information on working around a problem with OpenSSL's
DES headers.</i><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>

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>Symbols which are dlopened have an underscore prefixed. (This
behavior is detected by configure in SASL v2.)

<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>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>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.

</ul><p>

<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>

<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.

<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>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>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>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>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>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.

</ul><p>

<h2>Known Problems</h2><p>

<ul>
<li>The Kerberos v4 headers bundled with Mac OS X (and Kerberos for Macintosh) are not compatible with OS X's OpenSSL headers. The easiest solution, for now, is to build without using OpenSSL's <tt>libcrypto</tt>. To do this, specify the <tt>--without-openssl</tt> option to <tt>configure</tt>. After running <tt>configure</tt>, you will need to instruct the build system not to use OpenSSL's headers, either. Edit the <tt>config.h</tt> file, and look for the line:<p>
<tt>#define WITH_SSL_DES 1</tt><p>
Comment this line out (for example, by adding a double slash <tt>//</tt> to the beginning of it).<p>
<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.
</ul><p>