/
kdc_util.c
2692 lines (2391 loc) · 90.2 KB
/
kdc_util.c
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/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/*
* kdc/kdc_util.c
*
* Copyright 1990,1991,2007,2008,2009 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.
*
*
* Utility functions for the KDC implementation.
*/
/*
* Copyright (c) 2006-2008, Novell, 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.
* * The copyright holder's name is not used to endorse or promote products
* derived from this software without specific prior written permission.
*
* 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 OWNER 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 "k5-int.h"
#include "kdc_util.h"
#include "extern.h"
#include <stdio.h>
#include <ctype.h>
#include <syslog.h>
#include "adm.h"
#include "adm_proto.h"
#include "net-server.h"
#include <limits.h>
#ifdef USE_RCACHE
static char *kdc_current_rcname = (char *) NULL;
krb5_deltat rc_lifetime; /* See kdc_initialize_rcache() */
#endif
#ifdef KRBCONF_VAGUE_ERRORS
const int vague_errors = 1;
#else
const int vague_errors = 0;
#endif
#ifdef USE_RCACHE
/*
* initialize the replay cache.
*/
krb5_error_code
kdc_initialize_rcache(krb5_context kcontext, char *rcache_name)
{
krb5_error_code retval;
char *rcname;
char *sname;
rcname = (rcache_name) ? rcache_name : kdc_current_rcname;
/* rc_lifetime used elsewhere to verify we're not */
/* replaying really old data */
rc_lifetime = kcontext->clockskew;
if (!rcname)
rcname = KDCRCACHE;
if (!(retval = krb5_rc_resolve_full(kcontext, &kdc_rcache, rcname))) {
/* Recover or initialize the replay cache */
if (!(retval = krb5_rc_recover(kcontext, kdc_rcache)) ||
!(retval = krb5_rc_initialize(kcontext,
kdc_rcache,
kcontext->clockskew))
) {
/* Expunge the replay cache */
if (!(retval = krb5_rc_expunge(kcontext, kdc_rcache))) {
sname = kdc_current_rcname;
kdc_current_rcname = strdup(rcname);
if (sname)
free(sname);
}
}
if (retval)
krb5_rc_close(kcontext, kdc_rcache);
}
return(retval);
}
#endif
/*
* concatenate first two authdata arrays, returning an allocated replacement.
* The replacement should be freed with krb5_free_authdata().
*/
krb5_error_code
concat_authorization_data(krb5_authdata **first, krb5_authdata **second,
krb5_authdata ***output)
{
register int i, j;
register krb5_authdata **ptr, **retdata;
/* count up the entries */
i = 0;
if (first)
for (ptr = first; *ptr; ptr++)
i++;
if (second)
for (ptr = second; *ptr; ptr++)
i++;
retdata = (krb5_authdata **)malloc((i+1)*sizeof(*retdata));
if (!retdata)
return ENOMEM;
retdata[i] = 0; /* null-terminated array */
for (i = 0, j = 0, ptr = first; j < 2 ; ptr = second, j++)
while (ptr && *ptr) {
/* now walk & copy */
retdata[i] = (krb5_authdata *)malloc(sizeof(*retdata[i]));
if (!retdata[i]) {
krb5_free_authdata(kdc_context, retdata);
return ENOMEM;
}
*retdata[i] = **ptr;
if (!(retdata[i]->contents =
(krb5_octet *)malloc(retdata[i]->length))) {
free(retdata[i]);
retdata[i] = 0;
krb5_free_authdata(kdc_context, retdata);
return ENOMEM;
}
memcpy(retdata[i]->contents, (*ptr)->contents, retdata[i]->length);
ptr++;
i++;
}
*output = retdata;
return 0;
}
krb5_boolean
realm_compare(krb5_const_principal princ1, krb5_const_principal princ2)
{
return krb5_realm_compare(kdc_context, princ1, princ2);
}
krb5_boolean
is_local_principal(krb5_const_principal princ1)
{
return krb5_realm_compare(kdc_context, princ1, tgs_server);
}
/*
* Returns TRUE if the kerberos principal is the name of a Kerberos ticket
* service.
*/
krb5_boolean
krb5_is_tgs_principal(krb5_const_principal principal)
{
if ((krb5_princ_size(kdc_context, principal) > 0) &&
data_eq_string (*krb5_princ_component(kdc_context, principal, 0),
KRB5_TGS_NAME))
return TRUE;
return FALSE;
}
/* Returns TRUE if principal is the name of a cross-realm TGS. */
krb5_boolean
is_cross_tgs_principal(krb5_const_principal principal)
{
return (krb5_princ_size(kdc_context, principal) >= 2 &&
data_eq_string(*krb5_princ_component(kdc_context, principal, 0),
KRB5_TGS_NAME) &&
!data_eq(*krb5_princ_component(kdc_context, principal, 1),
*krb5_princ_realm(kcd_context, principal)));
}
/*
* given authentication data (provides seed for checksum), verify checksum
* for source data.
*/
static krb5_error_code
comp_cksum(krb5_context kcontext, krb5_data *source, krb5_ticket *ticket,
krb5_checksum *his_cksum)
{
krb5_error_code retval;
krb5_boolean valid;
if (!krb5_c_valid_cksumtype(his_cksum->checksum_type))
return KRB5KDC_ERR_SUMTYPE_NOSUPP;
/* must be collision proof */
if (!krb5_c_is_coll_proof_cksum(his_cksum->checksum_type))
return KRB5KRB_AP_ERR_INAPP_CKSUM;
/* verify checksum */
if ((retval = krb5_c_verify_checksum(kcontext, ticket->enc_part2->session,
KRB5_KEYUSAGE_TGS_REQ_AUTH_CKSUM,
source, his_cksum, &valid)))
return(retval);
if (!valid)
return(KRB5KRB_AP_ERR_BAD_INTEGRITY);
return(0);
}
krb5_pa_data *
find_pa_data(krb5_pa_data **padata, krb5_preauthtype pa_type)
{
return krb5int_find_pa_data(kdc_context, padata, pa_type);
}
krb5_error_code
kdc_process_tgs_req(krb5_kdc_req *request, const krb5_fulladdr *from,
krb5_data *pkt, krb5_ticket **ticket,
krb5_db_entry **krbtgt_ptr,
krb5_keyblock **tgskey,
krb5_keyblock **subkey,
krb5_pa_data **pa_tgs_req)
{
krb5_pa_data * tmppa;
krb5_ap_req * apreq;
krb5_error_code retval;
krb5_authdata **authdata = NULL;
krb5_data scratch1;
krb5_data * scratch = NULL;
krb5_boolean foreign_server = FALSE;
krb5_auth_context auth_context = NULL;
krb5_authenticator * authenticator = NULL;
krb5_checksum * his_cksum = NULL;
krb5_kvno kvno = 0;
krb5_db_entry * krbtgt = NULL;
*krbtgt_ptr = NULL;
*tgskey = NULL;
tmppa = find_pa_data(request->padata, KRB5_PADATA_AP_REQ);
if (!tmppa)
return KRB5KDC_ERR_PADATA_TYPE_NOSUPP;
scratch1.length = tmppa->length;
scratch1.data = (char *)tmppa->contents;
if ((retval = decode_krb5_ap_req(&scratch1, &apreq)))
return retval;
if (isflagset(apreq->ap_options, AP_OPTS_USE_SESSION_KEY) ||
isflagset(apreq->ap_options, AP_OPTS_MUTUAL_REQUIRED)) {
krb5_klog_syslog(LOG_INFO, "TGS_REQ: SESSION KEY or MUTUAL");
retval = KRB5KDC_ERR_POLICY;
goto cleanup;
}
/* If the "server" principal in the ticket is not something
in the local realm, then we must refuse to service the request
if the client claims to be from the local realm.
If we don't do this, then some other realm's nasty KDC can
claim to be authenticating a client from our realm, and we'll
give out tickets concurring with it!
we set a flag here for checking below.
*/
foreign_server = !is_local_principal(apreq->ticket->server);
if ((retval = krb5_auth_con_init(kdc_context, &auth_context)))
goto cleanup;
if ((retval = krb5_auth_con_setaddrs(kdc_context, auth_context, NULL,
from->address)) )
goto cleanup_auth_context;
#ifdef USE_RCACHE
if ((retval = krb5_auth_con_setrcache(kdc_context, auth_context,
kdc_rcache)))
goto cleanup_auth_context;
#endif
if ((retval = kdc_get_server_key(apreq->ticket, 0, foreign_server,
&krbtgt, tgskey, &kvno)))
goto cleanup_auth_context;
/*
* We do not use the KDB keytab because other parts of the TGS need the TGT key.
*/
retval = krb5_auth_con_setuseruserkey(kdc_context, auth_context, *tgskey);
if (retval)
goto cleanup_auth_context;
if ((retval = krb5_rd_req_decoded_anyflag(kdc_context, &auth_context, apreq,
apreq->ticket->server,
kdc_active_realm->realm_keytab,
NULL, ticket))) {
#ifdef USE_RCACHE
/*
* I'm not so sure that this is right, but it's better than nothing
* at all.
*
* If we choke in the rd_req because of the replay cache, then attempt
* to reinitialize the replay cache because somebody could have deleted
* it from underneath us (e.g. a cron job)
*/
if ((retval == KRB5_RC_IO_IO) ||
(retval == KRB5_RC_IO_UNKNOWN)) {
(void) krb5_rc_close(kdc_context, kdc_rcache);
kdc_rcache = (krb5_rcache) NULL;
if (!(retval = kdc_initialize_rcache(kdc_context, (char *) NULL))) {
if ((retval = krb5_auth_con_setrcache(kdc_context, auth_context,
kdc_rcache)) ||
(retval = krb5_rd_req_decoded_anyflag(kdc_context, &auth_context,
apreq, apreq->ticket->server,
kdc_active_realm->realm_keytab,
NULL, ticket))
)
goto cleanup_auth_context;
}
} else
goto cleanup_auth_context;
#else
goto cleanup_auth_context;
#endif
}
/* "invalid flag" tickets can must be used to validate */
if (isflagset((*ticket)->enc_part2->flags, TKT_FLG_INVALID)
&& !isflagset(request->kdc_options, KDC_OPT_VALIDATE)) {
retval = KRB5KRB_AP_ERR_TKT_INVALID;
goto cleanup_auth_context;
}
if ((retval = krb5_auth_con_getrecvsubkey(kdc_context,
auth_context, subkey)))
goto cleanup_auth_context;
if ((retval = krb5_auth_con_getauthenticator(kdc_context, auth_context,
&authenticator)))
goto cleanup_auth_context;
retval = krb5int_find_authdata(kdc_context,
(*ticket)->enc_part2->authorization_data,
authenticator->authorization_data,
KRB5_AUTHDATA_FX_ARMOR, &authdata);
if (retval != 0)
goto cleanup_authenticator;
if (authdata&& authdata[0]) {
krb5_set_error_message(kdc_context, KRB5KDC_ERR_POLICY,
"ticket valid only as FAST armor");
retval = KRB5KDC_ERR_POLICY;
krb5_free_authdata(kdc_context, authdata);
goto cleanup_authenticator;
}
krb5_free_authdata(kdc_context, authdata);
/* Check for a checksum */
if (!(his_cksum = authenticator->checksum)) {
retval = KRB5KRB_AP_ERR_INAPP_CKSUM;
goto cleanup_authenticator;
}
/* make sure the client is of proper lineage (see above) */
if (foreign_server &&
!find_pa_data(request->padata, KRB5_PADATA_FOR_USER)) {
if (is_local_principal((*ticket)->enc_part2->client)) {
/* someone in a foreign realm claiming to be local */
krb5_klog_syslog(LOG_INFO, "PROCESS_TGS: failed lineage check");
retval = KRB5KDC_ERR_POLICY;
goto cleanup_authenticator;
}
}
/*
* Check application checksum vs. tgs request
*
* We try checksumming the req-body two different ways: first we
* try reaching into the raw asn.1 stream (if available), and
* checksum that directly; if that fails, then we try encoding
* using our local asn.1 library.
*/
if (pkt && (fetch_asn1_field((unsigned char *) pkt->data,
1, 4, &scratch1) >= 0)) {
if (comp_cksum(kdc_context, &scratch1, *ticket, his_cksum)) {
if (!(retval = encode_krb5_kdc_req_body(request, &scratch)))
retval = comp_cksum(kdc_context, scratch, *ticket, his_cksum);
krb5_free_data(kdc_context, scratch);
if (retval)
goto cleanup_authenticator;
}
}
*pa_tgs_req = tmppa;
*krbtgt_ptr = krbtgt;
krbtgt = NULL;
cleanup_authenticator:
krb5_free_authenticator(kdc_context, authenticator);
cleanup_auth_context:
/* We do not want the free of the auth_context to close the rcache */
#ifdef USE_RCACHE
(void) krb5_auth_con_setrcache(kdc_context, auth_context, 0);
#endif
krb5_auth_con_free(kdc_context, auth_context);
cleanup:
if (retval != 0) {
krb5_free_keyblock(kdc_context, *tgskey);
*tgskey = NULL;
}
krb5_free_ap_req(kdc_context, apreq);
krb5_db_free_principal(kdc_context, krbtgt);
return retval;
}
/* XXX This function should no longer be necessary.
* The KDC should take the keytab associated with the realm and pass that to
* the krb5_rd_req_decode(). --proven
*
* It's actually still used by do_tgs_req() for u2u auth, and not too
* much else. -- tlyu
*/
krb5_error_code
kdc_get_server_key(krb5_ticket *ticket, unsigned int flags,
krb5_boolean match_enctype, krb5_db_entry **server_ptr,
krb5_keyblock **key, krb5_kvno *kvno)
{
krb5_error_code retval;
krb5_boolean similar;
krb5_key_data * server_key;
krb5_keyblock * mkey_ptr;
krb5_db_entry * server = NULL;
*server_ptr = NULL;
retval = krb5_db_get_principal(kdc_context, ticket->server, flags,
&server);
if (retval == KRB5_KDB_NOENTRY) {
char *sname;
if (!krb5_unparse_name(kdc_context, ticket->server, &sname)) {
limit_string(sname);
krb5_klog_syslog(LOG_ERR,"TGS_REQ: UNKNOWN SERVER: server='%s'",
sname);
free(sname);
}
return KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN;
} else if (retval)
return retval;
if (server->attributes & KRB5_KDB_DISALLOW_SVR ||
server->attributes & KRB5_KDB_DISALLOW_ALL_TIX) {
retval = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN;
goto errout;
}
if ((retval = krb5_dbe_find_mkey(kdc_context, master_keylist, server,
&mkey_ptr))) {
krb5_keylist_node *tmp_mkey_list;
/* try refreshing master key list */
/* XXX it would nice if we had the mkvno here for optimization */
if (krb5_db_fetch_mkey_list(kdc_context, master_princ,
&master_keyblock, 0, &tmp_mkey_list) == 0) {
krb5_dbe_free_key_list(kdc_context, master_keylist);
master_keylist = tmp_mkey_list;
retval = krb5_db_set_mkey_list(kdc_context, master_keylist);
if (retval)
goto errout;
if ((retval = krb5_dbe_find_mkey(kdc_context, master_keylist,
server, &mkey_ptr))) {
goto errout;
}
} else {
goto errout;
}
}
retval = krb5_dbe_find_enctype(kdc_context, server,
match_enctype ? ticket->enc_part.enctype : -1,
-1, (krb5_int32)ticket->enc_part.kvno,
&server_key);
if (retval)
goto errout;
if (!server_key) {
retval = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN;
goto errout;
}
if ((*key = (krb5_keyblock *)malloc(sizeof **key))) {
retval = krb5_dbe_decrypt_key_data(kdc_context, mkey_ptr, server_key,
*key, NULL);
} else
retval = ENOMEM;
retval = krb5_c_enctype_compare(kdc_context, ticket->enc_part.enctype,
(*key)->enctype, &similar);
if (retval)
goto errout;
if (!similar) {
retval = KRB5_KDB_NO_PERMITTED_KEY;
goto errout;
}
(*key)->enctype = ticket->enc_part.enctype;
*kvno = server_key->key_data_kvno;
*server_ptr = server;
server = NULL;
errout:
krb5_db_free_principal(kdc_context, server);
return retval;
}
/* This probably wants to be updated if you support last_req stuff */
static krb5_last_req_entry nolrentry = { KV5M_LAST_REQ_ENTRY, KRB5_LRQ_NONE, 0 };
static krb5_last_req_entry *nolrarray[] = { &nolrentry, 0 };
krb5_error_code
fetch_last_req_info(krb5_db_entry *dbentry, krb5_last_req_entry ***lrentry)
{
*lrentry = nolrarray;
return 0;
}
/* XXX! This is a temporary place-holder */
krb5_error_code
check_hot_list(krb5_ticket *ticket)
{
return 0;
}
#define MAX_REALM_LN 500
/*
* subrealm - determine if r2 is a subrealm of r1
*
* SUBREALM takes two realms, r1 and r2, and
* determines if r2 is a subrealm of r1.
* r2 is a subrealm of r1 if (r1 is a prefix
* of r2 AND r1 and r2 begin with a /) or if
* (r1 is a suffix of r2 and neither r1 nor r2
* begin with a /).
*
* RETURNS: If r2 is a subrealm, and r1 is a prefix, the number
* of characters in the suffix of r2 is returned as a
* negative number.
*
* If r2 is a subrealm, and r1 is a suffix, the number
* of characters in the prefix of r2 is returned as a
* positive number.
*
* If r2 is not a subrealm, SUBREALM returns 0.
*/
static int
subrealm(char *r1, char *r2)
{
size_t l1,l2;
l1 = strlen(r1);
l2 = strlen(r2);
if(l2 <= l1) return(0);
if((*r1 == '/') && (*r2 == '/') && (strncmp(r1,r2,l1) == 0)) return(l1-l2);
if((*r1 != '/') && (*r2 != '/') && (strncmp(r1,r2+l2-l1,l1) == 0))
return(l2-l1);
return(0);
}
/*
* add_to_transited Adds the name of the realm which issued the
* ticket granting ticket on which the new ticket to
* be issued is based (note that this is the same as
* the realm of the server listed in the ticket
* granting ticket.
*
* ASSUMPTIONS: This procedure assumes that the transited field from
* the existing ticket granting ticket already appears
* in compressed form. It will add the new realm while
* maintaining that form. As long as each successive
* realm is added using this (or a similar) routine, the
* transited field will be in compressed form. The
* basis step is an empty transited field which is, by
* its nature, in its most compressed form.
*
* ARGUMENTS: krb5_data *tgt_trans Transited field from TGT
* krb5_data *new_trans The transited field for the new ticket
* krb5_principal tgs Name of ticket granting server
* This includes the realm of the KDC
* that issued the ticket granting
* ticket. This is the realm that is
* to be added to the transited field.
* krb5_principal client Name of the client
* krb5_principal server The name of the requested server.
* This may be the an intermediate
* ticket granting server.
*
* The last two argument are needed since they are
* implicitly part of the transited field of the new ticket
* even though they are not explicitly listed.
*
* RETURNS: krb5_error_code - Success, or out of memory
*
* MODIFIES: new_trans: ->length will contain the length of the new
* transited field.
*
* If ->data was not null when this procedure
* is called, the memory referenced by ->data
* will be deallocated.
*
* Memory will be allocated for the new transited field
* ->data will be updated to point to the newly
* allocated memory.
*
* BUGS: The space allocated for the new transited field is the
* maximum that might be needed given the old transited field,
* and the realm to be added. This length is calculated
* assuming that no compression of the new realm is possible.
* This has no adverse consequences other than the allocation
* of more space than required.
*
* This procedure will not yet use the null subfield notation,
* and it will get confused if it sees it.
*
* This procedure does not check for quoted commas in realm
* names.
*/
static char *
data2string (krb5_data *d)
{
char *s;
s = malloc(d->length + 1);
if (s) {
memcpy(s, d->data, d->length);
s[d->length] = 0;
}
return s;
}
krb5_error_code
add_to_transited(krb5_data *tgt_trans, krb5_data *new_trans,
krb5_principal tgs, krb5_principal client,
krb5_principal server)
{
krb5_error_code retval;
char *realm;
char *trans;
char *otrans, *otrans_ptr;
size_t bufsize;
/* The following are for stepping through the transited field */
char prev[MAX_REALM_LN];
char next[MAX_REALM_LN];
char current[MAX_REALM_LN];
char exp[MAX_REALM_LN]; /* Expanded current realm name */
int i;
int clst, nlst; /* count of last character in current and next */
int pl, pl1; /* prefix length */
int added; /* TRUE = new realm has been added */
realm = data2string(krb5_princ_realm(kdc_context, tgs));
if (realm == NULL)
return(ENOMEM);
otrans = data2string(tgt_trans);
if (otrans == NULL) {
free(realm);
return(ENOMEM);
}
/* Keep track of start so we can free */
otrans_ptr = otrans;
/* +1 for null,
+1 for extra comma which may be added between
+1 for potential space when leading slash in realm */
bufsize = strlen(realm) + strlen(otrans) + 3;
if (bufsize > MAX_REALM_LN)
bufsize = MAX_REALM_LN;
if (!(trans = (char *) malloc(bufsize))) {
retval = ENOMEM;
goto fail;
}
if (new_trans->data) free(new_trans->data);
new_trans->data = trans;
new_trans->length = 0;
trans[0] = '\0';
/* For the purpose of appending, the realm preceding the first */
/* realm in the transited field is considered the null realm */
prev[0] = '\0';
/* read field into current */
for (i = 0; *otrans != '\0';) {
if (*otrans == '\\') {
if (*(++otrans) == '\0')
break;
else
continue;
}
if (*otrans == ',') {
otrans++;
break;
}
current[i++] = *otrans++;
if (i >= MAX_REALM_LN) {
retval = KRB5KRB_AP_ERR_ILL_CR_TKT;
goto fail;
}
}
current[i] = '\0';
added = (krb5_princ_realm(kdc_context, client)->length == strlen(realm) &&
!strncmp(krb5_princ_realm(kdc_context, client)->data, realm, strlen(realm))) ||
(krb5_princ_realm(kdc_context, server)->length == strlen(realm) &&
!strncmp(krb5_princ_realm(kdc_context, server)->data, realm, strlen(realm)));
while (current[0]) {
/* figure out expanded form of current name */
clst = strlen(current) - 1;
if (current[0] == ' ') {
strncpy(exp, current+1, sizeof(exp) - 1);
exp[sizeof(exp) - 1] = '\0';
}
else if ((current[0] == '/') && (prev[0] == '/')) {
strncpy(exp, prev, sizeof(exp) - 1);
exp[sizeof(exp) - 1] = '\0';
if (strlen(exp) + strlen(current) + 1 >= MAX_REALM_LN) {
retval = KRB5KRB_AP_ERR_ILL_CR_TKT;
goto fail;
}
strncat(exp, current, sizeof(exp) - 1 - strlen(exp));
}
else if (current[clst] == '.') {
strncpy(exp, current, sizeof(exp) - 1);
exp[sizeof(exp) - 1] = '\0';
if (strlen(exp) + strlen(prev) + 1 >= MAX_REALM_LN) {
retval = KRB5KRB_AP_ERR_ILL_CR_TKT;
goto fail;
}
strncat(exp, prev, sizeof(exp) - 1 - strlen(exp));
}
else {
strncpy(exp, current, sizeof(exp) - 1);
exp[sizeof(exp) - 1] = '\0';
}
/* read field into next */
for (i = 0; *otrans != '\0';) {
if (*otrans == '\\') {
if (*(++otrans) == '\0')
break;
else
continue;
}
if (*otrans == ',') {
otrans++;
break;
}
next[i++] = *otrans++;
if (i >= MAX_REALM_LN) {
retval = KRB5KRB_AP_ERR_ILL_CR_TKT;
goto fail;
}
}
next[i] = '\0';
nlst = i - 1;
if (!strcmp(exp, realm)) added = TRUE;
/* If we still have to insert the new realm */
if (!added) {
/* Is the next field compressed? If not, and if the new */
/* realm is a subrealm of the current realm, compress */
/* the new realm, and insert immediately following the */
/* current one. Note that we can not do this if the next*/
/* field is already compressed since it would mess up */
/* what has already been done. In most cases, this is */
/* not a problem because the realm to be added will be a */
/* subrealm of the next field too, and we will catch */
/* it in a future iteration. */
/* Note that the second test here is an unsigned comparison,
so the first half (or a cast) is also required. */
assert(nlst < 0 || nlst < (int)sizeof(next));
if ((nlst < 0 || next[nlst] != '.') &&
(next[0] != '/') &&
(pl = subrealm(exp, realm))) {
added = TRUE;
current[sizeof(current) - 1] = '\0';
if (strlen(current) + (pl>0?pl:-pl) + 2 >= MAX_REALM_LN) {
retval = KRB5KRB_AP_ERR_ILL_CR_TKT;
goto fail;
}
strncat(current, ",", sizeof(current) - 1 - strlen(current));
if (pl > 0) {
strncat(current, realm, (unsigned) pl);
}
else {
strncat(current, realm+strlen(realm)+pl, (unsigned) (-pl));
}
}
/* Whether or not the next field is compressed, if the */
/* realm to be added is a superrealm of the current realm,*/
/* then the current realm can be compressed. First the */
/* realm to be added must be compressed relative to the */
/* previous realm (if possible), and then the current */
/* realm compressed relative to the new realm. Note that */
/* if the realm to be added is also a superrealm of the */
/* previous realm, it would have been added earlier, and */
/* we would not reach this step this time around. */
else if ((pl = subrealm(realm, exp))) {
added = TRUE;
current[0] = '\0';
if ((pl1 = subrealm(prev,realm))) {
if (strlen(current) + (pl1>0?pl1:-pl1) + 1 >= MAX_REALM_LN) {
retval = KRB5KRB_AP_ERR_ILL_CR_TKT;
goto fail;
}
if (pl1 > 0) {
strncat(current, realm, (unsigned) pl1);
}
else {
strncat(current, realm+strlen(realm)+pl1, (unsigned) (-pl1));
}
}
else { /* If not a subrealm */
if ((realm[0] == '/') && prev[0]) {
if (strlen(current) + 2 >= MAX_REALM_LN) {
retval = KRB5KRB_AP_ERR_ILL_CR_TKT;
goto fail;
}
strncat(current, " ", sizeof(current) - 1 - strlen(current));
current[sizeof(current) - 1] = '\0';
}
if (strlen(current) + strlen(realm) + 1 >= MAX_REALM_LN) {
retval = KRB5KRB_AP_ERR_ILL_CR_TKT;
goto fail;
}
strncat(current, realm, sizeof(current) - 1 - strlen(current));
current[sizeof(current) - 1] = '\0';
}
if (strlen(current) + (pl>0?pl:-pl) + 2 >= MAX_REALM_LN) {
retval = KRB5KRB_AP_ERR_ILL_CR_TKT;
goto fail;
}
strncat(current,",", sizeof(current) - 1 - strlen(current));
current[sizeof(current) - 1] = '\0';
if (pl > 0) {
strncat(current, exp, (unsigned) pl);
}
else {
strncat(current, exp+strlen(exp)+pl, (unsigned)(-pl));
}
}
}
if (new_trans->length != 0) {
if (strlcat(trans, ",", bufsize) >= bufsize) {
retval = KRB5KRB_AP_ERR_ILL_CR_TKT;
goto fail;
}
}
if (strlcat(trans, current, bufsize) >= bufsize) {
retval = KRB5KRB_AP_ERR_ILL_CR_TKT;
goto fail;
}
new_trans->length = strlen(trans);
strncpy(prev, exp, sizeof(prev) - 1);
prev[sizeof(prev) - 1] = '\0';
strncpy(current, next, sizeof(current) - 1);
current[sizeof(current) - 1] = '\0';
}
if (!added) {
if (new_trans->length != 0) {
if (strlcat(trans, ",", bufsize) >= bufsize) {
retval = KRB5KRB_AP_ERR_ILL_CR_TKT;
goto fail;
}
}
if((realm[0] == '/') && trans[0]) {
if (strlcat(trans, " ", bufsize) >= bufsize) {
retval = KRB5KRB_AP_ERR_ILL_CR_TKT;
goto fail;
}
}
if (strlcat(trans, realm, bufsize) >= bufsize) {
retval = KRB5KRB_AP_ERR_ILL_CR_TKT;
goto fail;
}
new_trans->length = strlen(trans);
}
retval = 0;
fail:
free(realm);
free(otrans_ptr);
return (retval);
}
/*
* Routines that validate a AS request; checks a lot of things. :-)
*
* Returns a Kerberos protocol error number, which is _not_ the same
* as a com_err error number!
*/
#define AS_INVALID_OPTIONS (KDC_OPT_FORWARDED | KDC_OPT_PROXY | \
KDC_OPT_VALIDATE | KDC_OPT_RENEW | \
KDC_OPT_ENC_TKT_IN_SKEY | KDC_OPT_CNAME_IN_ADDL_TKT)
int
validate_as_request(register krb5_kdc_req *request, krb5_db_entry client,
krb5_db_entry server, krb5_timestamp kdc_time,
const char **status, krb5_data *e_data)
{
int errcode;
/*
* If an option is set that is only allowed in TGS requests, complain.
*/
if (request->kdc_options & AS_INVALID_OPTIONS) {
*status = "INVALID AS OPTIONS";
return KDC_ERR_BADOPTION;
}
/* The client must not be expired */
if (client.expiration && client.expiration < kdc_time) {
*status = "CLIENT EXPIRED";
if (vague_errors)
return(KRB_ERR_GENERIC);
else
return(KDC_ERR_NAME_EXP);
}
/* The client's password must not be expired, unless the server is
a KRB5_KDC_PWCHANGE_SERVICE. */
if (client.pw_expiration && client.pw_expiration < kdc_time &&
!isflagset(server.attributes, KRB5_KDB_PWCHANGE_SERVICE)) {
*status = "CLIENT KEY EXPIRED";
if (vague_errors)
return(KRB_ERR_GENERIC);
else
return(KDC_ERR_KEY_EXP);
}
/* The server must not be expired */
if (server.expiration && server.expiration < kdc_time) {
*status = "SERVICE EXPIRED";
return(KDC_ERR_SERVICE_EXP);
}
/*
* If the client requires password changing, then only allow the
* pwchange service.
*/
if (isflagset(client.attributes, KRB5_KDB_REQUIRES_PWCHANGE) &&
!isflagset(server.attributes, KRB5_KDB_PWCHANGE_SERVICE)) {
*status = "REQUIRED PWCHANGE";
return(KDC_ERR_KEY_EXP);
}
/* Client and server must allow postdating tickets */
if ((isflagset(request->kdc_options, KDC_OPT_ALLOW_POSTDATE) ||
isflagset(request->kdc_options, KDC_OPT_POSTDATED)) &&
(isflagset(client.attributes, KRB5_KDB_DISALLOW_POSTDATED) ||
isflagset(server.attributes, KRB5_KDB_DISALLOW_POSTDATED))) {