ccdefname.c
/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/* lib/krb5/os/ccdefname.c - Return default credential cache name */
/*
* Copyright 1990, 2007 by the Massachusetts Institute of Technology.
* All Rights Reserved.
*
* Export of this software from the United States of America may
* require a specific license from the United States Government.
* It is the responsibility of any person or organization contemplating
* export to obtain such a license before exporting.
*
* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
* distribute this software and its documentation for any purpose and
* without fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright notice and
* this permission notice appear in supporting documentation, and that
* the name of M.I.T. not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior
* permission. Furthermore if you modify this software you must label
* your software as modified software and not distribute it in such a
* fashion that it might be confused with the original M.I.T. software.
* M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is" without express
* or implied warranty.
*/
#define NEED_WINDOWS
#include "k5-int.h"
#include "../ccache/cc-int.h"
#include "os-proto.h"
#include <stdio.h>
#if defined(_WIN32)
static int get_from_registry_indirect(char *name_buf, int name_size)
{
/* If the RegKRB5CCNAME variable is set, it will point to
* the registry key that has the name of the cache to use.
* The Gradient PC-DCE sets the registry key
* [HKEY_CURRENT_USER\Software\Gradient\DCE\Default\KRB5CCNAME]
* to point at the cache file name (including the FILE: prefix).
* By indirecting with the RegKRB5CCNAME entry in kerberos.ini,
* we can accommodate other versions that might set a registry
* variable.
*/
char newkey[256];
LONG name_buf_size;
HKEY hkey;
int found = 0;
char *cp;
newkey[0] = 0;
GetPrivateProfileString(INI_FILES, "RegKRB5CCNAME", "",
newkey, sizeof(newkey), KERBEROS_INI);
if (!newkey[0])
return 0;
newkey[sizeof(newkey)-1] = 0;
cp = strrchr(newkey,'\\');
if (cp) {
*cp = '\0'; /* split the string */
cp++;
} else
cp = "";
if (RegOpenKeyEx(HKEY_CURRENT_USER, newkey, 0,
KEY_QUERY_VALUE, &hkey) != ERROR_SUCCESS)
return 0;
name_buf_size = name_size;
if (RegQueryValueEx(hkey, cp, 0, 0,
name_buf, &name_buf_size) != ERROR_SUCCESS)
{
RegCloseKey(hkey);
return 0;
}
RegCloseKey(hkey);
return 1;
}
static const char *key_path = "Software\\MIT\\Kerberos5";
static const char *value_name = "ccname";
static int
set_to_registry(
HKEY hBaseKey,
const char *name_buf
)
{
HRESULT result;
HKEY hKey;
if ((result = RegCreateKeyEx(hBaseKey, key_path, 0, NULL,
REG_OPTION_NON_VOLATILE, KEY_WRITE, NULL,
&hKey, NULL)) != ERROR_SUCCESS) {
return 0;
}
if (RegSetValueEx(hKey, value_name, 0, REG_SZ, name_buf,
strlen(name_buf)+1) != ERROR_SUCCESS) {
RegCloseKey(hKey);
return 0;
}
RegCloseKey(hKey);
return 1;
}
/*
* get_from_registry
*
* This will find the ccname in the registry. Returns 0 on error, non-zero
* on success.
*/
static int
get_from_registry(
HKEY hBaseKey,
char *name_buf,
int name_size
)
{
HKEY hKey;
DWORD name_buf_size = (DWORD)name_size;
if (RegOpenKeyEx(hBaseKey, key_path, 0, KEY_QUERY_VALUE,
&hKey) != ERROR_SUCCESS)
return 0;
if (RegQueryValueEx(hKey, value_name, 0, 0,
name_buf, &name_buf_size) != ERROR_SUCCESS)
{
RegCloseKey(hKey);
return 0;
}
RegCloseKey(hKey);
return 1;
}
#define APPEND_KRB5CC "\\krb5cc"
static int
try_dir(
char* dir,
char* buffer,
int buf_len
)
{
struct _stat s;
if (!dir)
return 0;
if (_stat(dir, &s))
return 0;
if (!(s.st_mode & _S_IFDIR))
return 0;
if (buffer != dir) {
strncpy(buffer, dir, buf_len);
buffer[buf_len-1]='\0';
}
strncat(buffer, APPEND_KRB5CC, buf_len-strlen(buffer));
buffer[buf_len-1] = '\0';
return 1;
}
static krb5_error_code
get_from_os_buffer(char *name_buf, unsigned int name_size)
{
char *prefix = krb5_cc_dfl_ops->prefix;
unsigned int size;
char *p;
DWORD gle;
SetLastError(0);
GetEnvironmentVariable(KRB5_ENV_CCNAME, name_buf, name_size);
gle = GetLastError();
if (gle == 0)
return 0;
else if (gle != ERROR_ENVVAR_NOT_FOUND)
return ENOMEM;
if (get_from_registry(HKEY_CURRENT_USER,
name_buf, name_size) != 0)
return 0;
if (get_from_registry(HKEY_LOCAL_MACHINE,
name_buf, name_size) != 0)
return 0;
if (get_from_registry_indirect(name_buf, name_size) != 0)
return 0;
strncpy(name_buf, prefix, name_size - 1);
name_buf[name_size - 1] = 0;
size = name_size - strlen(prefix);
if (size > 0)
strcat(name_buf, ":");
size--;
p = name_buf + name_size - size;
if (!strcmp(prefix, "API")) {
strncpy(p, "krb5cc", size);
} else if (!strcmp(prefix, "FILE") || !strcmp(prefix, "STDIO")) {
if (!try_dir(getenv("TEMP"), p, size) &&
!try_dir(getenv("TMP"), p, size))
{
unsigned int len = GetWindowsDirectory(p, size);
name_buf[name_size - 1] = 0;
if (len < size - sizeof(APPEND_KRB5CC))
strcat(p, APPEND_KRB5CC);
}
} else {
strncpy(p, "default_cache_name", size);
}
name_buf[name_size - 1] = 0;
return 0;
}
static void
get_from_os(krb5_context context)
{
krb5_error_code err;
char buf[1024];
if (get_from_os_buffer(buf, sizeof(buf)) == 0)
context->os_context.default_ccname = strdup(buf);
}
#else /* not _WIN32 */
static void
get_from_os(krb5_context context)
{
(void)k5_expand_path_tokens(context, DEFCCNAME,
&context->os_context.default_ccname);
}
#endif /* not _WIN32 */
#if defined(_WIN32)
static void
set_for_os(const char *name)
{
set_to_registry(HKEY_CURRENT_USER, name);
}
#else
static void
set_for_os(const char *name)
{
/* No implementation at present. */
}
#endif
/*
* Set the default ccache name for all processes for the current user
* (and the current context)
*/
krb5_error_code KRB5_CALLCONV
krb5int_cc_user_set_default_name(krb5_context context, const char *name)
{
krb5_error_code err;
err = krb5_cc_set_default_name(context, name);
if (err)
return err;
set_for_os(name);
return 0;
}
krb5_error_code KRB5_CALLCONV
krb5_cc_set_default_name(krb5_context context, const char *name)
{
krb5_os_context os_ctx;
char *new_ccname = NULL;
if (!context || context->magic != KV5M_CONTEXT)
return KV5M_CONTEXT;
if (name != NULL) {
new_ccname = strdup(name);
if (new_ccname == NULL)
return ENOMEM;
}
/* Free the old ccname and store the new one. */
os_ctx = &context->os_context;
free(os_ctx->default_ccname);
os_ctx->default_ccname = new_ccname;
return 0;
}
const char * KRB5_CALLCONV
krb5_cc_default_name(krb5_context context)
{
krb5_os_context os_ctx;
char *profstr, *envstr;
if (!context || context->magic != KV5M_CONTEXT)
return NULL;
os_ctx = &context->os_context;
if (os_ctx->default_ccname != NULL)
return os_ctx->default_ccname;
/* Try the environment variable first. */
envstr = secure_getenv(KRB5_ENV_CCNAME);
if (envstr != NULL) {
os_ctx->default_ccname = strdup(envstr);
return os_ctx->default_ccname;
}
if (profile_get_string(context->profile, KRB5_CONF_LIBDEFAULTS,
KRB5_CONF_DEFAULT_CCACHE_NAME, NULL, NULL,
&profstr) == 0 && profstr != NULL) {
(void)k5_expand_path_tokens(context, profstr, &os_ctx->default_ccname);
profile_release_string(profstr);
return os_ctx->default_ccname;
}
/* Fall back on the default ccache name for the OS. */
get_from_os(context);
return os_ctx->default_ccname;
}
