Files
2023-06-20 12:19:48 -05:00

209 lines
6.8 KiB
C

/*
* Copyright (c) 2006 - 2007 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* All rights reserved.
*
* Portions Copyright (c) 2018 AuriStor, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "krb5_locl.h"
#include "common_plugin.h"
/*
* Definitions:
*
* module - a category of plugin module, identified by subsystem
* (typically "krb5")
* dso - a library for a module containing a map of plugin
* types to plugins (e.g. "service_locator")
* plugin - a set of callbacks and state that follows the
* common plugin module definition (version, init, fini)
*
* Obviously it would have been clearer to use the term "module" rather than
* "DSO" given there is an internal "DSO", but "module" was already taken...
*
* modules := { module: dsos }
* dsos := { path, dsohandle, plugins-by-name }
* plugins-by-name := { plugin-name: [plug] }
* plug := { ftable, ctx }
*
* Some existing plugin consumers outside libkrb5 use the "krb5" module
* namespace, but going forward the module should match the consumer library
* name (e.g. libhdb should use the "hdb" module rather than "krb5").
*/
/**
* Register a plugin symbol name of specific type.
* @param context a Keberos context
* @param type type of plugin symbol
* @param name name of plugin symbol
* @param symbol a pointer to the named symbol
* @return In case of error a non zero error com_err error is returned
* and the Kerberos error string is set.
*
* @ingroup krb5_support
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_plugin_register(krb5_context context,
enum krb5_plugin_type type,
const char *name,
const void *symbol)
{
/*
* It's not clear that PLUGIN_TYPE_FUNC was ever used or supported. It likely
* would have caused _krb5_plugin_run_f() to crash as the previous implementation
* assumed PLUGIN_TYPE_DATA.
*/
if (type != PLUGIN_TYPE_DATA) {
krb5_warnx(context, "krb5_plugin_register: PLUGIN_TYPE_DATA no longer supported");
return EINVAL;
}
return heim_plugin_register(context->hcontext, (heim_pcontext)context,
"krb5", name, symbol);
}
/**
* Load plugins (new system) for the given module @name (typically
* "krb5") from the given directory @paths.
*
* Inputs:
*
* @context A krb5_context
* @name Name of plugin module (typically "krb5")
* @paths Array of directory paths where to look
*/
KRB5_LIB_FUNCTION void KRB5_LIB_CALL
_krb5_load_plugins(krb5_context context, const char *name, const char **paths)
{
heim_load_plugins(context->hcontext, name, paths);
}
/**
* Unload plugins (new system)
*/
KRB5_LIB_FUNCTION void KRB5_LIB_CALL
_krb5_unload_plugins(krb5_context context, const char *name)
{
heim_unload_plugins(context->hcontext, name);
}
/**
* Run plugins for the given @module (e.g., "krb5") and @name (e.g.,
* "kuserok"). Specifically, the @func is invoked once per-plugin with
* four arguments: the @context, the plugin symbol value (a pointer to a
* struct whose first three fields are the same as common_plugin_ftable),
* a context value produced by the plugin's init method, and @userctx.
*
* @func should unpack arguments for a plugin function and invoke it
* with arguments taken from @userctx. @func should save plugin
* outputs, if any, in @userctx.
*
* All loaded and registered plugins are invoked via @func until @func
* returns something other than KRB5_PLUGIN_NO_HANDLE. Plugins that
* have nothing to do for the given arguments should return
* KRB5_PLUGIN_NO_HANDLE.
*
* Inputs:
*
* @context A krb5_context
* @module Name of module (typically "krb5")
* @name Name of pluggable interface (e.g., "kuserok")
* @min_version Lowest acceptable plugin minor version number
* @flags Flags (none defined at this time)
* @userctx Callback data for the callback function @func
* @func A callback function, invoked once per-plugin
*
* Outputs: None, other than the return value and such outputs as are
* gathered by @func.
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
_krb5_plugin_run_f(krb5_context context,
const struct heim_plugin_data *caller,
int flags,
void *userctx,
krb5_error_code (KRB5_LIB_CALL *func)(krb5_context, const void *, void *, void *))
{
int32_t (HEIM_LIB_CALL *func2)(void *, const void *, void *, void *) = (void *)func;
return heim_plugin_run_f(context->hcontext, (heim_pcontext)context, caller,
flags, KRB5_PLUGIN_NO_HANDLE, userctx, func2);
}
/**
* Return a cookie identifying this instance of a library.
*
* Inputs:
*
* @context A krb5_context
* @module Our library name or a library we depend on
*
* Outputs: The instance cookie
*
* @ingroup krb5_support
*/
#ifdef WIN32
static uintptr_t
djb2(uintptr_t hash, unsigned char *str)
{
int c;
while (c = *str++)
hash = ((hash << 5) + hash) + c; /* hash * 33 + c */
return hash;
}
#endif
KRB5_LIB_FUNCTION uintptr_t KRB5_LIB_CALL
krb5_get_instance(const char *libname)
{
#ifdef WIN32
char *version;
char *name;
uintptr_t instance;
if (win32_getLibraryVersion("heimdal", &name, &version))
return 0;
instance = djb2(5381, name);
instance = djb2(instance, version);
free(name);
free(version);
return instance;
#else
static const char *instance = "libkrb5";
if (strcmp(libname, "krb5") == 0)
return (uintptr_t)instance;
return 0;
#endif
}