Windows: Registry based configuration

Load configuration data in the registry into a krb5_config_section.
Each registry key corresponds to a krb5_config_section and each
registry value becomes a bound string value.

The set of values contained in the root Heimdal registry key is
treated as if they were defined in the [libdefaults] section.

E.g. the configuration file:

[libdefaults]
foo = bar

[Foo]
x = y
y = {
  baz = quux
}

is equivalent to the registry keys:

[HKEY_CURRENT_USER\Software\Heimdal]
"foo"="bar"

[HKEY_CURRENT_USER\Software\Heimdal\Foo]
"x"="y"

[HKEY_CURRENT_USER\Software\Heimdal\Foo\y]
"baz"="quux"
This commit is contained in:
Asanka C. Herath
2010-09-22 17:28:12 -04:00
parent 392f9541f1
commit d247242f63
4 changed files with 354 additions and 1 deletions

View File

@@ -48,6 +48,7 @@ libkrb5_OBJS = \
$(OBJ)\changepw.obj \
$(OBJ)\codec.obj \
$(OBJ)\config_file.obj \
$(OBJ)\config_reg.obj \
$(OBJ)\convert_creds.obj \
$(OBJ)\constants.obj \
$(OBJ)\context.obj \
@@ -190,6 +191,7 @@ dist_libkrb5_la_SOURCES = \
changepw.c \
codec.c \
config_file.c \
config_reg.c \
convert_creds.c \
constants.c \
context.c \

View File

@@ -84,7 +84,7 @@ static krb5_error_code parse_list(struct fileptr *f, unsigned *lineno,
krb5_config_binding **parent,
const char **err_message);
static krb5_config_section *
krb5_config_section *
get_entry(krb5_config_section **parent, const char *name, int type)
{
krb5_config_section **q;

346
lib/krb5/config_reg.c Normal file
View File

@@ -0,0 +1,346 @@
/***********************************************************************
* Copyright (c) 2010, Secure Endpoints Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - 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.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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
* COPYRIGHT HOLDER 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"
#ifndef _WIN32
#error config_reg.c is only for Windows
#endif
#define REGPATH "SOFTWARE\\Heimdal"
/**
* Parse a registry value as a configuration value
*
* The following registry value types are handled:
*
* - REG_DWORD: The decimal string representation is used as the
* value.
*
* - REG_SZ: The string is used as-is.
*
* - REG_EXPAND_SZ: Environment variables in the string are expanded
* and the result is used as the value.
*
* - REG_MULTI_SZ: The list of strings is concatenated using a ' ' as
* a separator. No quoting is performed.
*
* Any other value type is rejected.
*/
static krb5_error_code
parse_reg_value(krb5_context context,
HKEY key, const char * valuename,
DWORD type, DWORD cbdata, krb5_config_section ** parent)
{
LONG rcode;
DWORD cb;
krb5_config_section *value;
krb5_error_code code = 0;
BYTE static_buffer[16384];
BYTE *pbuffer;
/* Size adjustments */
switch (type) {
case REG_DWORD:
if (cbdata != sizeof(DWORD)) {
krb5_set_error_message(context, KRB5_CONFIG_BADFORMAT,
"Unexpected size while reading registry value %s",
valuename);
return KRB5_CONFIG_BADFORMAT;
}
break;
case REG_SZ:
case REG_EXPAND_SZ:
cbdata += sizeof(char); /* Accout for potential missing NUL
* terminator. */
break;
case REG_MULTI_SZ:
cbdata += sizeof(char) * 2;
break;
default:
krb5_set_error_message(context, KRB5_CONFIG_BADFORMAT,
"Unexpected type while reading registry value %s",
valuename);
return KRB5_CONFIG_BADFORMAT;
}
if (cbdata <= sizeof(static_buffer))
pbuffer = &static_buffer[0];
else {
pbuffer = malloc(cbdata);
if (pbuffer == NULL)
return ENOMEM;
}
cb = cbdata;
rcode = RegQueryValueExA(key, valuename, NULL, NULL, pbuffer, &cb);
if (rcode != ERROR_SUCCESS) {
krb5_set_error_message(context, KRB5_CONFIG_BADFORMAT,
"Unexpected error while reading registry value %s",
valuename);
code = KRB5_CONFIG_BADFORMAT;
goto done;
}
if (cb > cbdata) {
krb5_set_error_message(context, KRB5_CONFIG_BADFORMAT,
"Unexpected error while reading registry value %s",
valuename);
code = KRB5_CONFIG_BADFORMAT;
goto done;
}
value = get_entry(parent, valuename, krb5_config_string);
if (value == NULL) {
code = ENOMEM;
goto done;
}
if (value->u.string != NULL) {
free(value->u.string);
value->u.string = NULL;
}
switch (type) {
case REG_DWORD:
{
asprintf(&value->u.string, "%d", *((DWORD *) pbuffer));
}
break;
case REG_SZ:
{
char * str = (char *) pbuffer;
if (str[cb - 1] != '\0')
str[cb] = '\0';
value->u.string = strdup(str);
}
break;
case REG_EXPAND_SZ:
{
char *str = (char *) pbuffer;
char expsz[32768]; /* Size of output buffer for
* ExpandEnvironmentStrings() is
* limited to 32K. */
if (str[cb - 1] != '\0')
str[cb] = '\0';
if (ExpandEnvironmentStrings(str, expsz, sizeof(expsz)/sizeof(expsz[0])) != 0) {
value->u.string = strdup(expsz);
} else {
code = KRB5_CONFIG_BADFORMAT;
krb5_set_error_message(context, KRB5_CONFIG_BADFORMAT,
"Overflow while expanding environment strings for registry value %s", valuename);
}
}
break;
case REG_MULTI_SZ:
{
char * str = (char *) pbuffer;
char * iter;
str[cbdata - 1] = '\0';
str[cbdata - 2] = '\0';
for (iter = str; *iter;) {
size_t len = strlen(iter);
iter += len;
if (iter[1] != '\0')
*iter++ = ' ';
else
break;
}
value->u.string = strdup(str);
}
break;
}
done:
if (pbuffer != static_buffer && pbuffer != NULL)
free(pbuffer);
return code;
}
static krb5_error_code
parse_reg_values(krb5_context context,
HKEY key,
krb5_config_section ** parent)
{
DWORD index;
LONG rcode;
for (index = 0; ; index ++) {
char name[16385];
DWORD cch = sizeof(name)/sizeof(name[0]);
DWORD type;
DWORD cbdata = 0;
krb5_error_code code;
rcode = RegEnumValue(key, index, name, &cch, NULL,
&type, NULL, &cbdata);
if (rcode != ERROR_SUCCESS)
break;
if (cbdata == 0)
continue;
code = parse_reg_value(context, key, name, type, cbdata, parent);
if (code != 0)
return code;
}
return 0;
}
static krb5_error_code
parse_reg_subkeys(krb5_context context,
HKEY key,
krb5_config_section ** parent)
{
DWORD index;
LONG rcode;
for (index = 0; ; index ++) {
HKEY subkey = NULL;
char name[256];
DWORD cch = sizeof(name)/sizeof(name[0]);
krb5_config_section *section = NULL;
krb5_error_code code;
rcode = RegEnumKeyEx(key, index, name, &cch, NULL, NULL, NULL, NULL);
if (rcode != ERROR_SUCCESS)
break;
rcode = RegOpenKeyEx(key, name, 0, KEY_READ, &subkey);
if (rcode != ERROR_SUCCESS)
continue;
section = get_entry(parent, name, krb5_config_list);
if (section == NULL) {
RegCloseKey(subkey);
return ENOMEM;
}
code = parse_reg_values(context, subkey, &section->u.list);
if (code) {
RegCloseKey(subkey);
return code;
}
code = parse_reg_subkeys(context, subkey, &section->u.list);
if (code) {
RegCloseKey(subkey);
return code;
}
RegCloseKey(subkey);
}
return 0;
}
static krb5_error_code
parse_reg_root(krb5_context context,
HKEY key,
krb5_config_section ** parent)
{
krb5_config_section *libdefaults = NULL;
krb5_error_code code = 0;
libdefaults = get_entry(parent, "libdefaults", krb5_config_list);
if (libdefaults == NULL) {
krb5_set_error_message(context, ENOMEM, "Out of memory while parsing configuration");
return ENOMEM;
}
code = parse_reg_values(context, key, &libdefaults->u.list);
if (code)
return code;
return parse_reg_subkeys(context, key, parent);
}
/**
* Load configuration from registry
*
* The registry keys 'HKCU\Software\Heimdal' and
* 'HKLM\Software\Heimdal' are treated as krb5.conf files. Each
* registry key corresponds to a configuration section (or bound list)
* and each value in a registry key is treated as a bound value. The
* set of values that are directly under the Heimdal key are treated
* as if they were defined in the [libdefaults] section.
*
* @see parse_reg_value() for details about how each type of value is handled.
*/
krb5_error_code
krb5_load_config_from_registry(krb5_context context,
krb5_config_section ** res)
{
HKEY key = NULL;
LONG rcode;
krb5_error_code code = 0;
rcode = RegOpenKeyEx(HKEY_LOCAL_MACHINE, REGPATH, 0, KEY_READ, &key);
if (rcode == ERROR_SUCCESS) {
code = parse_reg_root(context, key, res);
RegCloseKey(key);
key = NULL;
if (code)
return code;
}
rcode = RegOpenKeyEx(HKEY_CURRENT_USER, REGPATH, 0, KEY_READ, &key);
if (rcode == ERROR_SUCCESS) {
code = parse_reg_root(context, key, res);
RegCloseKey(key);
key = NULL;
if (code)
return code;
}
return 0;
}

View File

@@ -616,6 +616,11 @@ krb5_set_config_files(krb5_context context, char **filenames)
if(tmp == NULL)
return ENXIO;
#endif
#ifdef _WIN32
krb5_load_config_from_registry(context, &tmp);
#endif
krb5_config_file_free(context, context->cf);
context->cf = tmp;
ret = init_context_from_config_file(context);