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/*
* Copyright (c) 1997 - 2001 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* All rights reserved.
*
* 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 "kadm5_locl.h"
RCSID("$Id$");
static struct units acl_units[] = {
{ "all", KADM5_PRIV_ALL },
{ "change-password",KADM5_PRIV_CPW },
{ "cpw", KADM5_PRIV_CPW },
{ "list", KADM5_PRIV_LIST },
{ "delete", KADM5_PRIV_DELETE },
{ "modify", KADM5_PRIV_MODIFY },
{ "add", KADM5_PRIV_ADD },
{ "get", KADM5_PRIV_GET },
{ "get-keys", KADM5_PRIV_GET_KEYS },
{ NULL, 0 }
};
kadm5_ret_t
_kadm5_string_to_privs(const char *s, uint32_t* privs)
{
int flags;
flags = parse_flags(s, acl_units, 0);
if(flags < 0)
return KADM5_FAILURE;
*privs = flags;
return 0;
}
kadm5_ret_t
_kadm5_privs_to_string(uint32_t privs, char *string, size_t len)
{
if(privs == 0)
strlcpy(string, "none", len);
else
unparse_flags(privs, acl_units + 1, string, len);
return 0;
}
/*
* retrieve the right for the current caller on `princ' (NULL means all)
* and store them in `ret_flags'
* return 0 or an error.
*/
static kadm5_ret_t
fetch_acl (kadm5_server_context *context,
krb5_const_principal princ,
unsigned *ret_flags)
{
FILE *f;
krb5_error_code ret = 0;
char buf[256];
*ret_flags = 0;
/* no acl file -> no rights */
f = fopen(context->config.acl_file, "r");
if (f == NULL)
return 0;
while(fgets(buf, sizeof(buf), f) != NULL) {
char *foo = NULL, *p;
krb5_principal this_princ;
unsigned flags = 0;
p = strtok_r(buf, " \t\n", &foo);
if(p == NULL)
continue;
if (*p == '#') /* comment */
continue;
ret = krb5_parse_name(context->context, p, &this_princ);
if(ret)
break;
if(!krb5_principal_compare(context->context,
context->caller, this_princ)) {
krb5_free_principal(context->context, this_princ);
continue;
}
krb5_free_principal(context->context, this_princ);
p = strtok_r(NULL, " \t\n", &foo);
if(p == NULL)
continue;
ret = _kadm5_string_to_privs(p, &flags);
if (ret)
break;
p = strtok_r(NULL, " \t\n", &foo);
if (p == NULL) {
*ret_flags = flags;
break;
}
if (princ != NULL) {
krb5_principal pattern_princ;
krb5_boolean match;
const char *c0 = krb5_principal_get_comp_string(context->context,
princ, 0);
const char *pat_c0;
ret = krb5_parse_name(context->context, p, &pattern_princ);
if (ret)
break;
pat_c0 = krb5_principal_get_comp_string(context->context,
pattern_princ, 0);
match = krb5_principal_match(context->context,
princ, pattern_princ);
/*
* If `princ' is a WELLKNOWN name, then require the WELLKNOWN label
* be matched exactly.
*
* FIXME: We could do something similar for krbtgt and kadmin other
* principal types.
*/
if (match && c0 && strcmp(c0, "WELLKNOWN") == 0 &&
(!pat_c0 || strcmp(pat_c0, "WELLKNOWN") != 0))
match = FALSE;
krb5_free_principal(context->context, pattern_princ);
if (match) {
*ret_flags = flags;
break;
}
}
}
fclose(f);
return ret;
}
krb5_boolean
_kadm5_is_kadmin_service_p(kadm5_server_context *context)
{
krb5_boolean ret;
krb5_principal princ;
if (krb5_parse_name(context->context, KADM5_ADMIN_SERVICE, &princ) != 0)
return FALSE;
ret = krb5_principal_compare(context->context, context->caller, princ);
krb5_free_principal(context->context, princ);
return ret;
}
/*
* set global acl flags in `context' for the current caller.
* return 0 on success or an error
*/
kadm5_ret_t
_kadm5_acl_init(kadm5_server_context *context)
{
if (_kadm5_is_kadmin_service_p(context)) {
context->acl_flags = KADM5_PRIV_ALL;
return 0;
}
return fetch_acl (context, NULL, &context->acl_flags);
}
/*
* check if `flags' allows `op'
* return 0 if OK or an error
*/
static kadm5_ret_t
check_flags (unsigned op,
unsigned flags)
{
unsigned res = ~flags & op;
if(res & KADM5_PRIV_GET)
return KADM5_AUTH_GET;
if(res & KADM5_PRIV_GET_KEYS)
return KADM5_AUTH_GET_KEYS;
if(res & KADM5_PRIV_ADD)
return KADM5_AUTH_ADD;
if(res & KADM5_PRIV_MODIFY)
return KADM5_AUTH_MODIFY;
if(res & KADM5_PRIV_DELETE)
return KADM5_AUTH_DELETE;
if(res & KADM5_PRIV_CPW)
return KADM5_AUTH_CHANGEPW;
if(res & KADM5_PRIV_LIST)
return KADM5_AUTH_LIST;
if(res)
return KADM5_AUTH_INSUFFICIENT;
return 0;
}
/*
* return 0 if the current caller in `context' is allowed to perform
* `op' on `princ' and otherwise an error
* princ == NULL if it's not relevant.
*/
kadm5_ret_t
_kadm5_acl_check_permission(kadm5_server_context *context,
unsigned op,
krb5_const_principal princ)
{
kadm5_ret_t ret;
unsigned princ_flags;
ret = check_flags (op, context->acl_flags);
if (ret == 0)
return ret;
ret = fetch_acl (context, princ, &princ_flags);
if (ret)
return ret;
return check_flags (op, princ_flags);
}
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