/* $NetBSD: kerberos5.c,v 1.9 2023/06/19 21:41:41 christos Exp $ */
/*
* Copyright (c) 1997-2007 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 "kdc_locl.h"
#define MAX_TIME ((time_t)((1U << 31) - 1))
void
_kdc_fix_time(time_t **t)
{
if(*t == NULL){
ALLOC(*t);
**t = MAX_TIME;
}
if(**t == 0) **t = MAX_TIME; /* fix for old clients */
}
static int
realloc_method_data(METHOD_DATA *md)
{
PA_DATA *pa;
pa = realloc(md->val, (md->len + 1) * sizeof(*md->val));
if(pa == NULL)
return ENOMEM;
md->val = pa;
md->len++;
return 0;
}
static void
set_salt_padata(METHOD_DATA *md, Salt *salt)
{
if (salt) {
realloc_method_data(md);
md->val[md->len - 1].padata_type = salt->type;
der_copy_octet_string(&salt->salt,
&md->val[md->len - 1].padata_value);
}
}
const PA_DATA*
_kdc_find_padata(const KDC_REQ *req, int *start, int type)
{
if (req->padata == NULL)
return NULL;
while((size_t)*start < req->padata->len){
(*start)++;
if(req->padata->val[*start - 1].padata_type == (unsigned)type)
return &req->padata->val[*start - 1];
}
return NULL;
}
/*
* This is a hack to allow predefined weak services, like afs to
* still use weak types
*/
krb5_boolean
_kdc_is_weak_exception(krb5_principal principal, krb5_enctype etype)
{
if (principal->name.name_string.len > 0 &&
strcmp(principal->name.name_string.val[0], "afs") == 0 &&
(etype == (krb5_enctype)ETYPE_DES_CBC_CRC
|| etype == (krb5_enctype)ETYPE_DES_CBC_MD4
|| etype == (krb5_enctype)ETYPE_DES_CBC_MD5))
return TRUE;
return FALSE;
}
/*
* Detect if `key' is the using the the precomputed `default_salt'.
*/
static krb5_boolean
is_default_salt_p(const krb5_salt *default_salt, const Key *key)
{
if (key->salt == NULL)
return TRUE;
if (default_salt->salttype != key->salt->type)
return FALSE;
if (krb5_data_cmp(&default_salt->saltvalue, &key->salt->salt))
return FALSE;
return TRUE;
}
/*
* Detect if `key' is the using the the precomputed `default_salt'
* (for des-cbc-crc) or any salt otherwise.
*
* This is for avoiding Kerberos v4 (yes really) keys in AS-REQ as
* that salt is strange, and a buggy client will try to use the
* principal as the salt and not the returned value.
*/
static krb5_boolean
is_good_salt_p(const krb5_salt *default_salt, const Key *key)
{
if (key->key.keytype == KRB5_ENCTYPE_DES_CBC_CRC)
return is_default_salt_p(default_salt, key);
return TRUE;
}
krb5_boolean
_kdc_is_anon_request(const KDC_REQ *req)
{
const KDC_REQ_BODY *b = &req->req_body;
/*
* Versions of Heimdal from 0.9rc1 through 1.50 use bit 14 instead
* of 16 for request_anonymous, as indicated in the anonymous draft
* prior to version 11. Bit 14 is assigned to S4U2Proxy, but S4U2Proxy
* requests are only sent to the TGS and, in any case, would have an
* additional ticket present.
*/
return b->kdc_options.request_anonymous ||
(b->kdc_options.cname_in_addl_tkt && !b->additional_tickets);
}
/*
* return the first appropriate key of `princ' in `ret_key'. Look for
* all the etypes in (`etypes', `len'), stopping as soon as we find
* one, but preferring one that has default salt.
*/
krb5_error_code
_kdc_find_etype(krb5_context context, krb5_boolean use_strongest_session_key,
krb5_boolean is_preauth, hdb_entry_ex *princ,
krb5_enctype *etypes, unsigned len,
krb5_enctype *ret_enctype, Key **ret_key)
{
krb5_error_code ret;
krb5_salt def_salt;
krb5_enctype enctype = (krb5_enctype)ETYPE_NULL;
const krb5_enctype *p;
Key *key = NULL;
int i, k;
/* We'll want to avoid keys with v4 salted keys in the pre-auth case... */
ret = krb5_get_pw_salt(context, princ->entry.principal, &def_salt);
if (ret)
return ret;
ret = KRB5KDC_ERR_ETYPE_NOSUPP;
if (use_strongest_session_key) {
/*
* Pick the strongest key that the KDC, target service, and
* client all support, using the local cryptosystem enctype
* list in strongest-to-weakest order to drive the search.
*
* This is not what RFC4120 says to do, but it encourages
* adoption of stronger enctypes. This doesn't play well with
* clients that have multiple Kerberos client implementations
* available with different supported enctype lists.
*/
/* drive the search with local supported enctypes list */
p = krb5_kerberos_enctypes(context);
for (i = 0;
p[i] != (krb5_enctype)ETYPE_NULL && enctype == (krb5_enctype)ETYPE_NULL;
i++) {
if (krb5_enctype_valid(context, p[i]) != 0 &&
!_kdc_is_weak_exception(princ->entry.principal, p[i]))
continue;
/* check that the client supports it too */
for (k = 0; k < len && enctype == (krb5_enctype)ETYPE_NULL; k++) {
if (p[i] != etypes[k])
continue;
/* check target princ support */
key = NULL;
while (hdb_next_enctype2key(context, &princ->entry, NULL,
p[i], &key) == 0) {
if (key->key.keyvalue.length == 0) {
ret = KRB5KDC_ERR_NULL_KEY;
continue;
}
enctype = p[i];
ret = 0;
if (is_preauth && ret_key != NULL &&
!is_good_salt_p(&def_salt, key))
continue;
}
}
}
} else {
/*
* Pick the first key from the client's enctype list that is
* supported by the cryptosystem and by the given principal.
*
* RFC4120 says we SHOULD pick the first _strong_ key from the
* client's list... not the first key... If the admin disallows
* weak enctypes in krb5.conf and selects this key selection
* algorithm, then we get exactly what RFC4120 says.
*/
for(i = 0; ret != 0 && i < len; i++) {
if (krb5_enctype_valid(context, etypes[i]) != 0 &&
!_kdc_is_weak_exception(princ->entry.principal, etypes[i]))
continue;
key = NULL;
while (ret != 0 &&
hdb_next_enctype2key(context, &princ->entry, NULL,
etypes[i], &key) == 0) {
if (key->key.keyvalue.length == 0) {
ret = KRB5KDC_ERR_NULL_KEY;
continue;
}
enctype = etypes[i];
ret = 0;
if (is_preauth && ret_key != NULL &&
!is_good_salt_p(&def_salt, key))
continue;
}
}
}
if (enctype == (krb5_enctype)ETYPE_NULL) {
/*
* if the service principal is one for which there is a known 1DES
* exception and no other enctype matches both the client request and
* the service key list, provide a DES-CBC-CRC key.
*/
if (ret_key == NULL &&
_kdc_is_weak_exception(princ->entry.principal, ETYPE_DES_CBC_CRC)) {
ret = 0;
enctype = ETYPE_DES_CBC_CRC;
} else {
ret = KRB5KDC_ERR_ETYPE_NOSUPP;
}
}
if (ret == 0) {
if (ret_enctype != NULL)
*ret_enctype = enctype;
if (ret_key != NULL)
*ret_key = key;
}
krb5_free_salt (context, def_salt);
return ret;
}
krb5_error_code
_kdc_make_anonymous_principalname (PrincipalName *pn)
{
pn->name_type = KRB5_NT_WELLKNOWN;
pn->name_string.len = 2;
pn->name_string.val = calloc(2, sizeof(*pn->name_string.val));
if (pn->name_string.val == NULL)
goto failed;
pn->name_string.val[0] = strdup(KRB5_WELLKNOWN_NAME);
if (pn->name_string.val[0] == NULL)
goto failed;
pn->name_string.val[1] = strdup(KRB5_ANON_NAME);
if (pn->name_string.val[1] == NULL)
goto failed;
return 0;
failed:
free_PrincipalName(pn);
pn->name_type = KRB5_NT_UNKNOWN;
pn->name_string.len = 0;
pn->name_string.val = NULL;
return ENOMEM;
}
static void
_kdc_r_log(kdc_request_t r, int level, const char *fmt, ...)
{
va_list ap;
char *s;
va_start(ap, fmt);
s = kdc_log_msg_va(r->context, r->config, level, fmt, ap);
if(s) free(s);
va_end(ap);
}
static void
_kdc_set_e_text(kdc_request_t r, const char *e_text)
{
r->e_text = e_text;
kdc_log(r->context, r->config, 0, "%s", e_text);
}
void
_kdc_log_timestamp(krb5_context context,
krb5_kdc_configuration *config,
const char *type,
KerberosTime authtime, KerberosTime *starttime,
KerberosTime endtime, KerberosTime *renew_till)
{
char authtime_str[100], starttime_str[100],
endtime_str[100], renewtime_str[100];
krb5_format_time(context, authtime,
authtime_str, sizeof(authtime_str), TRUE);
if (starttime)
krb5_format_time(context, *starttime,
starttime_str, sizeof(starttime_str), TRUE);
else
strlcpy(starttime_str, "unset", sizeof(starttime_str));
krb5_format_time(context, endtime,
endtime_str, sizeof(endtime_str), TRUE);
if (renew_till)
krb5_format_time(context, *renew_till,
renewtime_str, sizeof(renewtime_str), TRUE);
else
strlcpy(renewtime_str, "unset", sizeof(renewtime_str));
kdc_log(context, config, 5,
"%s authtime: %s starttime: %s endtime: %s renew till: %s",
type, authtime_str, starttime_str, endtime_str, renewtime_str);
}
/*
*
*/
#ifdef PKINIT
static krb5_error_code
pa_pkinit_validate(kdc_request_t r, const PA_DATA *pa)
{
pk_client_params *pkp = NULL;
char *client_cert = NULL;
krb5_error_code ret;
ret = _kdc_pk_rd_padata(r->context, r->config, &r->req, pa, r->client, &pkp);
if (ret || pkp == NULL) {
ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
_kdc_r_log(r, 5, "Failed to decode PKINIT PA-DATA -- %s",
r->client_name);
goto out;
}
ret = _kdc_pk_check_client(r->context,
r->config,
r->clientdb,
r->client,
pkp,
&client_cert);
if (ret) {
_kdc_set_e_text(r, "PKINIT certificate not allowed to "
"impersonate principal");
goto out;
}
_kdc_r_log(r, 0, "PKINIT pre-authentication succeeded -- %s using %s",
r->client_name, client_cert);
free(client_cert);
ret = _kdc_pk_mk_pa_reply(r->context, r->config, pkp, r->client,
r->sessionetype, &r->req, &r->request,
&r->reply_key, &r->session_key, &r->outpadata);
if (ret) {
_kdc_set_e_text(r, "Failed to build PK-INIT reply");
goto out;
}
#if 0
ret = _kdc_add_inital_verified_cas(r->context, r->config,
pkp, &r->et);
#endif
out:
if (pkp)
_kdc_pk_free_client_param(r->context, pkp);
return ret;
}
#endif /* PKINIT */
/*
*
*/
static krb5_error_code
make_pa_enc_challange(krb5_context context, METHOD_DATA *md,
krb5_crypto crypto)
{
PA_ENC_TS_ENC p;
unsigned char *buf;
size_t buf_size;
size_t len;
EncryptedData encdata;
krb5_error_code ret;
int32_t usec;
int usec2;
krb5_us_timeofday (context, &p.patimestamp, &usec);
usec2 = usec;
p.pausec = &usec2;
ASN1_MALLOC_ENCODE(PA_ENC_TS_ENC, buf, buf_size, &p, &len, ret);
if (ret)
return ret;
if(buf_size != len)
krb5_abortx(context, "internal error in ASN.1 encoder");
ret = krb5_encrypt_EncryptedData(context,
crypto,
KRB5_KU_ENC_CHALLENGE_KDC,
buf,
len,
0,
&encdata);
free(buf);
if (ret)
return ret;
ASN1_MALLOC_ENCODE(EncryptedData, buf, buf_size, &encdata, &len, ret);
free_EncryptedData(&encdata);
if (ret)
return ret;
if(buf_size != len)
krb5_abortx(context, "internal error in ASN.1 encoder");
ret = krb5_padata_add(context, md, KRB5_PADATA_ENCRYPTED_CHALLENGE, buf, len);
if (ret)
free(buf);
return ret;
}
static krb5_error_code
pa_enc_chal_validate(kdc_request_t r, const PA_DATA *pa)
{
krb5_data pepper1, pepper2, ts_data;
int invalidPassword = 0;
EncryptedData enc_data;
krb5_enctype aenctype;
krb5_error_code ret;
struct Key *k;
size_t size;
int i;
heim_assert(r->armor_crypto != NULL, "ENC-CHAL called for non FAST");
if (_kdc_is_anon_request(&r->req)) {
ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
kdc_log(r->context, r->config, 0, "ENC-CHALL doesn't support anon");
return ret;
}
ret = decode_EncryptedData(pa->padata_value.data,
pa->padata_value.length,
&enc_data,
&size);
if (ret) {
ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
_kdc_r_log(r, 5, "Failed to decode PA-DATA -- %s",
r->client_name);
return ret;
}
pepper1.data = "clientchallengearmor";
pepper1.length = strlen(pepper1.data);
pepper2.data = "challengelongterm";
pepper2.length = strlen(pepper2.data);
krb5_crypto_getenctype(r->context, r->armor_crypto, &aenctype);
for (i = 0; i < r->client->entry.keys.len; i++) {
krb5_crypto challangecrypto, longtermcrypto;
krb5_keyblock challangekey;
PA_ENC_TS_ENC p;
k = &r->client->entry.keys.val[i];
ret = krb5_crypto_init(r->context, &k->key, 0, &longtermcrypto);
if (ret)
continue;
ret = krb5_crypto_fx_cf2(r->context, r->armor_crypto, longtermcrypto,
&pepper1, &pepper2, aenctype,
&challangekey);
krb5_crypto_destroy(r->context, longtermcrypto);
if (ret)
continue;
ret = krb5_crypto_init(r->context, &challangekey, 0,
&challangecrypto);
if (ret)
continue;
ret = krb5_decrypt_EncryptedData(r->context, challangecrypto,
KRB5_KU_ENC_CHALLENGE_CLIENT,
&enc_data,
&ts_data);
if (ret) {
const char *msg = krb5_get_error_message(r->context, ret);
krb5_error_code ret2;
char *str = NULL;
invalidPassword = 1;
ret2 = krb5_enctype_to_string(r->context, k->key.keytype, &str);
if (ret2)
str = NULL;
_kdc_r_log(r, 5, "Failed to decrypt ENC-CHAL -- %s "
"(enctype %s) error %s",
r->client_name, str ? str : "unknown enctype", msg);
krb5_free_error_message(r->context, msg);
free(str);
continue;
}
ret = decode_PA_ENC_TS_ENC(ts_data.data,
ts_data.length,
&p,
&size);
krb5_data_free(&ts_data);
if(ret){
krb5_crypto_destroy(r->context, challangecrypto);
ret = KRB5KDC_ERR_PREAUTH_FAILED;
_kdc_r_log(r, 5, "Failed to decode PA-ENC-TS_ENC -- %s",
r->client_name);
continue;
}
if (labs(kdc_time - p.patimestamp) > r->context->max_skew) {
char client_time[100];
krb5_crypto_destroy(r->context, challangecrypto);
krb5_format_time(r->context, p.patimestamp,
client_time, sizeof(client_time), TRUE);
ret = KRB5KRB_AP_ERR_SKEW;
_kdc_r_log(r, 0, "Too large time skew, "
"client time %s is out by %u > %u seconds -- %s",
client_time,
(unsigned)labs(kdc_time - p.patimestamp),
r->context->max_skew,
r->client_name);
free_PA_ENC_TS_ENC(&p);
goto out;
}
free_PA_ENC_TS_ENC(&p);
ret = make_pa_enc_challange(r->context, &r->outpadata,
challangecrypto);
krb5_crypto_destroy(r->context, challangecrypto);
if (ret)
goto out;
set_salt_padata(&r->outpadata, k->salt);
krb5_free_keyblock_contents(r->context, &r->reply_key);
ret = krb5_copy_keyblock_contents(r->context, &k->key, &r->reply_key);
if (ret)
goto out;
/*
* Success
*/
if (r->clientdb->hdb_auth_status)
r->clientdb->hdb_auth_status(r->context, r->clientdb, r->client,
HDB_AUTH_SUCCESS);
goto out;
}
if (invalidPassword && r->clientdb->hdb_auth_status) {
r->clientdb->hdb_auth_status(r->context, r->clientdb, r->client,
HDB_AUTH_WRONG_PASSWORD);
ret = KRB5KDC_ERR_PREAUTH_FAILED;
}
out:
free_EncryptedData(&enc_data);
return ret;
}
static krb5_error_code
pa_enc_ts_validate(kdc_request_t r, const PA_DATA *pa)
{
EncryptedData enc_data;
krb5_error_code ret;
krb5_crypto crypto;
krb5_data ts_data;
PA_ENC_TS_ENC p;
size_t len;
Key *pa_key;
char *str;
ret = decode_EncryptedData(pa->padata_value.data,
pa->padata_value.length,
&enc_data,
&len);
if (ret) {
ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
_kdc_r_log(r, 5, "Failed to decode PA-DATA -- %s",
r->client_name);
goto out;
}
ret = hdb_enctype2key(r->context, &r->client->entry, NULL,
enc_data.etype, &pa_key);
if(ret){
char *estr;
_kdc_set_e_text(r, "No key matching entype");
ret = KRB5KDC_ERR_ETYPE_NOSUPP;
if(krb5_enctype_to_string(r->context, enc_data.etype, &estr))
estr = NULL;
if(estr == NULL)
_kdc_r_log(r, 5,
"No client key matching pa-data (%d) -- %s",
enc_data.etype, r->client_name);
else
_kdc_r_log(r, 5,
"No client key matching pa-data (%s) -- %s",
estr, r->client_name);
free(estr);
free_EncryptedData(&enc_data);
goto out;
}
try_next_key:
ret = krb5_crypto_init(r->context, &pa_key->key, 0, &crypto);
if (ret) {
const char *msg = krb5_get_error_message(r->context, ret);
_kdc_r_log(r, 0, "krb5_crypto_init failed: %s", msg);
krb5_free_error_message(r->context, msg);
free_EncryptedData(&enc_data);
goto out;
}
ret = krb5_decrypt_EncryptedData (r->context,
crypto,
KRB5_KU_PA_ENC_TIMESTAMP,
&enc_data,
&ts_data);
krb5_crypto_destroy(r->context, crypto);
/*
* Since the user might have several keys with the same
* enctype but with diffrent salting, we need to try all
* the keys with the same enctype.
*/
if(ret){
krb5_error_code ret2;
const char *msg = krb5_get_error_message(r->context, ret);
ret2 = krb5_enctype_to_string(r->context,
pa_key->key.keytype, &str);
if (ret2)
str = NULL;
_kdc_r_log(r, 5, "Failed to decrypt PA-DATA -- %s "
"(enctype %s) error %s",
r->client_name, str ? str : "unknown enctype", msg);
krb5_free_error_message(r->context, msg);
free(str);
if(hdb_next_enctype2key(r->context, &r->client->entry, NULL,
enc_data.etype, &pa_key) == 0)
goto try_next_key;
free_EncryptedData(&enc_data);
if (r->clientdb->hdb_auth_status)
r->clientdb->hdb_auth_status(r->context, r->clientdb, r->client,
HDB_AUTH_WRONG_PASSWORD);
ret = KRB5KDC_ERR_PREAUTH_FAILED;
goto out;
}
free_EncryptedData(&enc_data);
ret = decode_PA_ENC_TS_ENC(ts_data.data,
ts_data.length,
&p,
&len);
krb5_data_free(&ts_data);
if(ret){
ret = KRB5KDC_ERR_PREAUTH_FAILED;
_kdc_r_log(r, 5, "Failed to decode PA-ENC-TS_ENC -- %s",
r->client_name);
goto out;
}
if (labs(kdc_time - p.patimestamp) > r->context->max_skew) {
char client_time[100];
krb5_format_time(r->context, p.patimestamp,
client_time, sizeof(client_time), TRUE);
ret = KRB5KRB_AP_ERR_SKEW;
_kdc_r_log(r, 0, "Too large time skew, "
"client time %s is out by %u > %u seconds -- %s",
client_time,
(unsigned)labs(kdc_time - p.patimestamp),
r->context->max_skew,
r->client_name);
/*
* The following is needed to make windows clients to
* retry using the timestamp in the error message, if
* there is a e_text, they become unhappy.
*/
r->e_text = NULL;
free_PA_ENC_TS_ENC(&p);
goto out;
}
free_PA_ENC_TS_ENC(&p);
set_salt_padata(&r->outpadata, pa_key->salt);
ret = krb5_copy_keyblock_contents(r->context, &pa_key->key, &r->reply_key);
if (ret)
return ret;
ret = krb5_enctype_to_string(r->context, pa_key->key.keytype, &str);
if (ret)
str = NULL;
_kdc_r_log(r, 2, "ENC-TS Pre-authentication succeeded -- %s using %s",
r->client_name, str ? str : "unknown enctype");
free(str);
ret = 0;
out:
return ret;
}
struct kdc_patypes {
int type;
char *name;
unsigned int flags;
#define PA_ANNOUNCE 1
#define PA_REQ_FAST 2 /* only use inside fast */
krb5_error_code (*validate)(kdc_request_t, const PA_DATA *pa);
};
static const struct kdc_patypes pat[] = {
#ifdef PKINIT
{
KRB5_PADATA_PK_AS_REQ, "PK-INIT(ietf)", PA_ANNOUNCE,
pa_pkinit_validate
},
{
KRB5_PADATA_PK_AS_REQ_WIN, "PK-INIT(win2k)", PA_ANNOUNCE,
pa_pkinit_validate
},
{
KRB5_PADATA_PKINIT_KX, "Anonymous PK-INIT", PA_ANNOUNCE,
NULL
},
#else
{ KRB5_PADATA_PK_AS_REQ, "PK-INIT(ietf)", 0, NULL },
{ KRB5_PADATA_PK_AS_REQ_WIN, "PK-INIT(win2k)", 0, NULL },
{ KRB5_PADATA_PKINIT_KX, "Anonymous PK-INIT", 0, NULL },
#endif
{ KRB5_PADATA_PA_PK_OCSP_RESPONSE , "OCSP", 0, NULL },
{
KRB5_PADATA_ENC_TIMESTAMP , "ENC-TS",
PA_ANNOUNCE,
pa_enc_ts_validate
},
{
KRB5_PADATA_ENCRYPTED_CHALLENGE , "ENC-CHAL",
PA_ANNOUNCE | PA_REQ_FAST,
pa_enc_chal_validate
},
{ KRB5_PADATA_REQ_ENC_PA_REP , "REQ-ENC-PA-REP", 0, NULL },
{ KRB5_PADATA_FX_FAST, "FX-FAST", PA_ANNOUNCE, NULL },
{ KRB5_PADATA_FX_ERROR, "FX-ERROR", 0, NULL },
{ KRB5_PADATA_FX_COOKIE, "FX-COOKIE", 0, NULL }
};
static void
log_patypes(krb5_context context,
krb5_kdc_configuration *config,
METHOD_DATA *padata)
{
struct rk_strpool *p = NULL;
char *str;
size_t n, m;
for (n = 0; n < padata->len; n++) {
for (m = 0; m < sizeof(pat) / sizeof(pat[0]); m++) {
if (padata->val[n].padata_type == pat[m].type) {
p = rk_strpoolprintf(p, "%s", pat[m].name);
break;
}
}
if (m == sizeof(pat) / sizeof(pat[0]))
p = rk_strpoolprintf(p, "%d", padata->val[n].padata_type);
if (p && n + 1 < padata->len)
p = rk_strpoolprintf(p, ", ");
if (p == NULL) {
kdc_log(context, config, 0, "out of memory");
return;
}
}
if (p == NULL)
p = rk_strpoolprintf(p, "none");
str = rk_strpoolcollect(p);
kdc_log(context, config, 0, "Client sent patypes: %s", str);
free(str);
}
/*
*
*/
krb5_error_code
_kdc_encode_reply(krb5_context context,
krb5_kdc_configuration *config,
krb5_crypto armor_crypto, uint32_t nonce,
KDC_REP *rep, EncTicketPart *et, EncKDCRepPart *ek,
krb5_enctype etype,
int skvno, const EncryptionKey *skey,
int ckvno, const EncryptionKey *reply_key,
int rk_is_subkey,
const char **e_text,
krb5_data *reply)
{
unsigned char *buf;
size_t buf_size;
size_t len = 0;
krb5_error_code ret;
krb5_crypto crypto;
ASN1_MALLOC_ENCODE(EncTicketPart, buf, buf_size, et, &len, ret);
if(ret) {
const char *msg = krb5_get_error_message(context, ret);
kdc_log(context, config, 0, "Failed to encode ticket: %s", msg);
krb5_free_error_message(context, msg);
return ret;
}
if(buf_size != len)
krb5_abortx(context, "Internal error in ASN.1 encoder");
ret = krb5_crypto_init(context, skey, etype, &crypto);
if (ret) {
const char *msg = krb5_get_error_message(context, ret);
kdc_log(context, config, 0, "krb5_crypto_init failed: %s", msg);
krb5_free_error_message(context, msg);
free(buf);
return ret;
}
ret = krb5_encrypt_EncryptedData(context,
crypto,
KRB5_KU_TICKET,
buf,
len,
skvno,
&rep->ticket.enc_part);
free(buf);
krb5_crypto_destroy(context, crypto);
if(ret) {
const char *msg = krb5_get_error_message(context, ret);
kdc_log(context, config, 0, "Failed to encrypt data: %s", msg);
krb5_free_error_message(context, msg);
return ret;
}
if (armor_crypto) {
krb5_data data;
krb5_keyblock *strengthen_key = NULL;
KrbFastFinished finished;
kdc_log(context, config, 0, "FAST armor protection");
memset(&finished, 0, sizeof(finished));
krb5_data_zero(&data);
finished.timestamp = kdc_time;
finished.usec = 0;
finished.crealm = et->crealm;
finished.cname = et->cname;
ASN1_MALLOC_ENCODE(Ticket, data.data, data.length,
&rep->ticket, &len, ret);
if (ret)
return ret;
if (data.length != len)
krb5_abortx(context, "internal asn.1 error");
ret = krb5_create_checksum(context, armor_crypto,
KRB5_KU_FAST_FINISHED, 0,
data.data, data.length,
&finished.ticket_checksum);
krb5_data_free(&data);
if (ret)
return ret;
ret = _kdc_fast_mk_response(context, armor_crypto,
rep->padata, strengthen_key, &finished,
nonce, &data);
free_Checksum(&finished.ticket_checksum);
if (ret)
return ret;
if (rep->padata) {
free_METHOD_DATA(rep->padata);
} else {
rep->padata = calloc(1, sizeof(*(rep->padata)));
if (rep->padata == NULL) {
krb5_data_free(&data);
return ENOMEM;
}
}
ret = krb5_padata_add(context, rep->padata,
KRB5_PADATA_FX_FAST,
data.data, data.length);
if (ret)
return ret;
/*
* Hide client name of privacy reasons
*/
if (1 /* r->fast_options.hide_client_names */) {
rep->crealm[0] = '\0';
free_PrincipalName(&rep->cname);
rep->cname.name_type = 0;
}
}
if(rep->msg_type == krb_as_rep && !config->encode_as_rep_as_tgs_rep)
ASN1_MALLOC_ENCODE(EncASRepPart, buf, buf_size, ek, &len, ret);
else
ASN1_MALLOC_ENCODE(EncTGSRepPart, buf, buf_size, ek, &len, ret);
if(ret) {
const char *msg = krb5_get_error_message(context, ret);
kdc_log(context, config, 0, "Failed to encode KDC-REP: %s", msg);
krb5_free_error_message(context, msg);
return ret;
}
if(buf_size != len) {
free(buf);
kdc_log(context, config, 0, "Internal error in ASN.1 encoder");
*e_text = "KDC internal error";
return KRB5KRB_ERR_GENERIC;
}
ret = krb5_crypto_init(context, reply_key, 0, &crypto);
if (ret) {
const char *msg = krb5_get_error_message(context, ret);
free(buf);
kdc_log(context, config, 0, "krb5_crypto_init failed: %s", msg);
krb5_free_error_message(context, msg);
return ret;
}
if(rep->msg_type == krb_as_rep) {
krb5_encrypt_EncryptedData(context,
crypto,
KRB5_KU_AS_REP_ENC_PART,
buf,
len,
ckvno,
&rep->enc_part);
free(buf);
ASN1_MALLOC_ENCODE(AS_REP, buf, buf_size, rep, &len, ret);
} else {
krb5_encrypt_EncryptedData(context,
crypto,
rk_is_subkey ? KRB5_KU_TGS_REP_ENC_PART_SUB_KEY : KRB5_KU_TGS_REP_ENC_PART_SESSION,
buf,
len,
ckvno,
&rep->enc_part);
free(buf);
ASN1_MALLOC_ENCODE(TGS_REP, buf, buf_size, rep, &len, ret);
}
krb5_crypto_destroy(context, crypto);
if(ret) {
const char *msg = krb5_get_error_message(context, ret);
kdc_log(context, config, 0, "Failed to encode KDC-REP: %s", msg);
krb5_free_error_message(context, msg);
return ret;
}
if(buf_size != len) {
free(buf);
kdc_log(context, config, 0, "Internal error in ASN.1 encoder");
*e_text = "KDC internal error";
return KRB5KRB_ERR_GENERIC;
}
reply->data = buf;
reply->length = buf_size;
return 0;
}
/*
* Return 1 if the client have only older enctypes, this is for
* determining if the server should send ETYPE_INFO2 or not.
*/
static int
older_enctype(krb5_enctype enctype)
{
switch (enctype) {
case ETYPE_DES_CBC_CRC:
case ETYPE_DES_CBC_MD4:
case ETYPE_DES_CBC_MD5:
case ETYPE_DES3_CBC_SHA1:
case ETYPE_ARCFOUR_HMAC_MD5:
case ETYPE_ARCFOUR_HMAC_MD5_56:
/*
* The following three is "old" windows enctypes and is needed for
* windows 2000 hosts.
*/
case ETYPE_ARCFOUR_MD4:
case ETYPE_ARCFOUR_HMAC_OLD:
case ETYPE_ARCFOUR_HMAC_OLD_EXP:
return 1;
default:
return 0;
}
}
/*
*
*/
static krb5_error_code
make_etype_info_entry(krb5_context context, ETYPE_INFO_ENTRY *ent, Key *key)
{
ent->etype = key->key.keytype;
if(key->salt){
#if 0
ALLOC(ent->salttype);
if(key->salt->type == hdb_pw_salt)
*ent->salttype = 0; /* or 1? or NULL? */
else if(key->salt->type == hdb_afs3_salt)
*ent->salttype = 2;
else {
kdc_log(context, config, 0, "unknown salt-type: %d",
key->salt->type);
return KRB5KRB_ERR_GENERIC;
}
/* according to `the specs', we can't send a salt if
we have AFS3 salted key, but that requires that you
*know* what cell you are using (e.g by assuming
that the cell is the same as the realm in lower
case) */
#elif 0
ALLOC(ent->salttype);
*ent->salttype = key->salt->type;
#else
/*
* We shouldn't sent salttype since it is incompatible with the
* specification and it breaks windows clients. The afs
* salting problem is solved by using KRB5-PADATA-AFS3-SALT
* implemented in Heimdal 0.7 and later.
*/
ent->salttype = NULL;
#endif
krb5_copy_data(context, &key->salt->salt,
&ent->salt);
} else {
/* we return no salt type at all, as that should indicate
* the default salt type and make everybody happy. some
* systems (like w2k) dislike being told the salt type
* here. */
ent->salttype = NULL;
ent->salt = NULL;
}
return 0;
}
static krb5_error_code
get_pa_etype_info(krb5_context context,
krb5_kdc_configuration *config,
METHOD_DATA *md, Key *ckey)
{
krb5_error_code ret = 0;
ETYPE_INFO pa;
unsigned char *buf;
size_t len;
pa.len = 1;
pa.val = calloc(1, sizeof(pa.val[0]));
if(pa.val == NULL)
return ENOMEM;
ret = make_etype_info_entry(context, &pa.val[0], ckey);
if (ret) {
free_ETYPE_INFO(&pa);
return ret;
}
ASN1_MALLOC_ENCODE(ETYPE_INFO, buf, len, &pa, &len, ret);
free_ETYPE_INFO(&pa);
if(ret)
return ret;
ret = realloc_method_data(md);
if(ret) {
free(buf);
return ret;
}
md->val[md->len - 1].padata_type = KRB5_PADATA_ETYPE_INFO;
md->val[md->len - 1].padata_value.length = len;
md->val[md->len - 1].padata_value.data = buf;
return 0;
}
/*
*
*/
extern int _krb5_AES_SHA1_string_to_default_iterator;
extern int _krb5_AES_SHA2_string_to_default_iterator;
static krb5_error_code
make_s2kparams(int value, size_t len, krb5_data **ps2kparams)
{
krb5_data *s2kparams;
krb5_error_code ret;
ALLOC(s2kparams);
if (s2kparams == NULL)
return ENOMEM;
ret = krb5_data_alloc(s2kparams, len);
if (ret) {
free(s2kparams);
return ret;
}
_krb5_put_int(s2kparams->data, value, len);
*ps2kparams = s2kparams;
return 0;
}
static krb5_error_code
make_etype_info2_entry(ETYPE_INFO2_ENTRY *ent, Key *key)
{
krb5_error_code ret;
ent->etype = key->key.keytype;
if(key->salt) {
ALLOC(ent->salt);
if (ent->salt == NULL)
return ENOMEM;
*ent->salt = malloc(key->salt->salt.length + 1);
if (*ent->salt == NULL) {
free(ent->salt);
ent->salt = NULL;
return ENOMEM;
}
memcpy(*ent->salt, key->salt->salt.data, key->salt->salt.length);
(*ent->salt)[key->salt->salt.length] = '\0';
} else
ent->salt = NULL;
ent->s2kparams = NULL;
switch (key->key.keytype) {
case ETYPE_AES128_CTS_HMAC_SHA1_96:
case ETYPE_AES256_CTS_HMAC_SHA1_96:
ret = make_s2kparams(_krb5_AES_SHA1_string_to_default_iterator,
4, &ent->s2kparams);
break;
case KRB5_ENCTYPE_AES128_CTS_HMAC_SHA256_128:
case KRB5_ENCTYPE_AES256_CTS_HMAC_SHA384_192:
ret = make_s2kparams(_krb5_AES_SHA2_string_to_default_iterator,
4, &ent->s2kparams);
break;
case ETYPE_DES_CBC_CRC:
case ETYPE_DES_CBC_MD4:
case ETYPE_DES_CBC_MD5:
/* Check if this was a AFS3 salted key */
if(key->salt && key->salt->type == hdb_afs3_salt)
ret = make_s2kparams(1, 1, &ent->s2kparams);
else
ret = 0;
break;
default:
ret = 0;
break;
}
return ret;
}
/*
* Return an ETYPE-INFO2. Enctypes are storted the same way as in the
* database (client supported enctypes first, then the unsupported
* enctypes).
*/
static krb5_error_code
get_pa_etype_info2(krb5_context context,
krb5_kdc_configuration *config,
METHOD_DATA *md, Key *ckey)
{
krb5_error_code ret = 0;
ETYPE_INFO2 pa;
unsigned char *buf;
size_t len;
pa.len = 1;
pa.val = calloc(1, sizeof(pa.val[0]));
if(pa.val == NULL)
return ENOMEM;
ret = make_etype_info2_entry(&pa.val[0], ckey);
if (ret) {
free_ETYPE_INFO2(&pa);
return ret;
}
ASN1_MALLOC_ENCODE(ETYPE_INFO2, buf, len, &pa, &len, ret);
free_ETYPE_INFO2(&pa);
if(ret)
return ret;
ret = realloc_method_data(md);
if(ret) {
free(buf);
return ret;
}
md->val[md->len - 1].padata_type = KRB5_PADATA_ETYPE_INFO2;
md->val[md->len - 1].padata_value.length = len;
md->val[md->len - 1].padata_value.data = buf;
return 0;
}
/*
*
*/
static void
log_as_req(krb5_context context,
krb5_kdc_configuration *config,
krb5_enctype cetype,
krb5_enctype setype,
const KDC_REQ_BODY *b)
{
krb5_error_code ret;
struct rk_strpool *p;
char *str;
size_t i;
p = rk_strpoolprintf(NULL, "%s", "Client supported enctypes: ");
for (i = 0; i < b->etype.len; i++) {
ret = krb5_enctype_to_string(context, b->etype.val[i], &str);
if (ret == 0) {
p = rk_strpoolprintf(p, "%s", str);
free(str);
} else
p = rk_strpoolprintf(p, "%d", b->etype.val[i]);
if (p && i + 1 < b->etype.len)
p = rk_strpoolprintf(p, ", ");
if (p == NULL) {
kdc_log(context, config, 0, "out of memory");
return;
}
}
if (p == NULL)
p = rk_strpoolprintf(p, "no encryption types");
{
char *cet;
char *set;
ret = krb5_enctype_to_string(context, cetype, &cet);
if(ret == 0) {
ret = krb5_enctype_to_string(context, setype, &set);
if (ret == 0) {
p = rk_strpoolprintf(p, ", using %s/%s", cet, set);
free(set);
}
free(cet);
}
if (ret != 0)
p = rk_strpoolprintf(p, ", using enctypes %d/%d",
cetype, setype);
}
str = rk_strpoolcollect(p);
kdc_log(context, config, 0, "%s", str);
free(str);
{
char fixedstr[128];
unparse_flags(KDCOptions2int(b->kdc_options), asn1_KDCOptions_units(),
fixedstr, sizeof(fixedstr));
if(*fixedstr)
kdc_log(context, config, 0, "Requested flags: %s", fixedstr);
}
}
/*
* verify the flags on `client' and `server', returning 0
* if they are OK and generating an error messages and returning
* and error code otherwise.
*/
krb5_error_code
kdc_check_flags(krb5_context context,
krb5_kdc_configuration *config,
hdb_entry_ex *client_ex, const char *client_name,
hdb_entry_ex *server_ex, const char *server_name,
krb5_boolean is_as_req)
{
if(client_ex != NULL) {
hdb_entry *client = &client_ex->entry;
/* check client */
if (client->flags.locked_out) {
kdc_log(context, config, 0,
"Client (%s) is locked out", client_name);
return KRB5KDC_ERR_POLICY;
}
if (client->flags.invalid) {
kdc_log(context, config, 0,
"Client (%s) has invalid bit set", client_name);
return KRB5KDC_ERR_POLICY;
}
if(!client->flags.client){
kdc_log(context, config, 0,
"Principal may not act as client -- %s", client_name);
return KRB5KDC_ERR_POLICY;
}
if (client->valid_start && *client->valid_start > kdc_time) {
char starttime_str[100];
krb5_format_time(context, *client->valid_start,
starttime_str, sizeof(starttime_str), TRUE);
kdc_log(context, config, 0,
"Client not yet valid until %s -- %s",
starttime_str, client_name);
return KRB5KDC_ERR_CLIENT_NOTYET;
}
if (client->valid_end && *client->valid_end < kdc_time) {
char endtime_str[100];
krb5_format_time(context, *client->valid_end,
endtime_str, sizeof(endtime_str), TRUE);
kdc_log(context, config, 0,
"Client expired at %s -- %s",
endtime_str, client_name);
return KRB5KDC_ERR_NAME_EXP;
}
if (client->flags.require_pwchange &&
(server_ex == NULL || !server_ex->entry.flags.change_pw)) {
kdc_log(context, config, 0,
"Client's key must be changed -- %s", client_name);
return KRB5KDC_ERR_KEY_EXPIRED;
}
if (client->pw_end && *client->pw_end < kdc_time
&& (server_ex == NULL || !server_ex->entry.flags.change_pw)) {
char pwend_str[100];
krb5_format_time(context, *client->pw_end,
pwend_str, sizeof(pwend_str), TRUE);
kdc_log(context, config, 0,
"Client's key has expired at %s -- %s",
pwend_str, client_name);
return KRB5KDC_ERR_KEY_EXPIRED;
}
}
/* check server */
if (server_ex != NULL) {
hdb_entry *server = &server_ex->entry;
if (server->flags.locked_out) {
kdc_log(context, config, 0,
"Client server locked out -- %s", server_name);
return KRB5KDC_ERR_POLICY;
}
if (server->flags.invalid) {
kdc_log(context, config, 0,
"Server has invalid flag set -- %s", server_name);
return KRB5KDC_ERR_POLICY;
}
if(!server->flags.server){
kdc_log(context, config, 0,
"Principal may not act as server -- %s", server_name);
return KRB5KDC_ERR_POLICY;
}
if(!is_as_req && server->flags.initial) {
kdc_log(context, config, 0,
"AS-REQ is required for server -- %s", server_name);
return KRB5KDC_ERR_POLICY;
}
if (server->valid_start && *server->valid_start > kdc_time) {
char starttime_str[100];
krb5_format_time(context, *server->valid_start,
starttime_str, sizeof(starttime_str), TRUE);
kdc_log(context, config, 0,
"Server not yet valid until %s -- %s",
starttime_str, server_name);
return KRB5KDC_ERR_SERVICE_NOTYET;
}
if (server->valid_end && *server->valid_end < kdc_time) {
char endtime_str[100];
krb5_format_time(context, *server->valid_end,
endtime_str, sizeof(endtime_str), TRUE);
kdc_log(context, config, 0,
"Server expired at %s -- %s",
endtime_str, server_name);
return KRB5KDC_ERR_SERVICE_EXP;
}
if (server->pw_end && *server->pw_end < kdc_time) {
char pwend_str[100];
krb5_format_time(context, *server->pw_end,
pwend_str, sizeof(pwend_str), TRUE);
kdc_log(context, config, 0,
"Server's key has expired at -- %s",
pwend_str, server_name);
return KRB5KDC_ERR_KEY_EXPIRED;
}
}
return 0;
}
/*
* Return TRUE if `from' is part of `addresses' taking into consideration
* the configuration variables that tells us how strict we should be about
* these checks
*/
krb5_boolean
_kdc_check_addresses(krb5_context context,
krb5_kdc_configuration *config,
HostAddresses *addresses, const struct sockaddr *from)
{
krb5_error_code ret;
krb5_address addr;
krb5_boolean result;
krb5_boolean only_netbios = TRUE;
size_t i;
if(config->check_ticket_addresses == 0)
return TRUE;
if(addresses == NULL)
return config->allow_null_ticket_addresses;
for (i = 0; i < addresses->len; ++i) {
if (addresses->val[i].addr_type != KRB5_ADDRESS_NETBIOS) {
only_netbios = FALSE;
}
}
/* Windows sends it's netbios name, which I can only assume is
* used for the 'allowed workstations' check. This is painful,
* but we still want to check IP addresses if they happen to be
* present.
*/
if(only_netbios)
return config->allow_null_ticket_addresses;
ret = krb5_sockaddr2address (context, from, &addr);
if(ret)
return FALSE;
result = krb5_address_search(context, &addr, addresses);
krb5_free_address (context, &addr);
return result;
}
/*
*
*/
krb5_error_code
_kdc_check_anon_policy (krb5_context context,
krb5_kdc_configuration *config,
hdb_entry_ex *client,
hdb_entry_ex *server)
{
if (!config->allow_anonymous){
kdc_log(context, config, 0,
"Request for anonymous ticket denied by local policy");
return KRB5KDC_ERR_POLICY;
}
return 0;
}
/*
*
*/
static krb5_boolean
send_pac_p(krb5_context context, KDC_REQ *req)
{
krb5_error_code ret;
PA_PAC_REQUEST pacreq;
const PA_DATA *pa;
int i = 0;
pa = _kdc_find_padata(req, &i, KRB5_PADATA_PA_PAC_REQUEST);
if (pa == NULL)
return TRUE;
ret = decode_PA_PAC_REQUEST(pa->padata_value.data,
pa->padata_value.length,
&pacreq,
NULL);
if (ret)
return TRUE;
i = pacreq.include_pac;
free_PA_PAC_REQUEST(&pacreq);
if (i == 0)
return FALSE;
return TRUE;
}
/*
*
*/
static krb5_error_code
generate_pac(kdc_request_t r, Key *skey)
{
krb5_error_code ret;
krb5_pac p = NULL;
krb5_data data;
ret = _kdc_pac_generate(r->context, r->client, &p);
if (ret) {
_kdc_r_log(r, 0, "PAC generation failed for -- %s",
r->client_name);
return ret;
}
if (p == NULL)
return 0;
ret = _krb5_pac_sign(r->context, p, r->et.authtime,
r->client->entry.principal,
&skey->key, /* Server key */
&skey->key, /* FIXME: should be krbtgt key */
&data);
krb5_pac_free(r->context, p);
if (ret) {
_kdc_r_log(r, 0, "PAC signing failed for -- %s",
r->client_name);
return ret;
}
ret = _kdc_tkt_add_if_relevant_ad(r->context, &r->et,
KRB5_AUTHDATA_WIN2K_PAC,
&data);
krb5_data_free(&data);
return ret;
}
/*
*
*/
krb5_boolean
_kdc_is_anonymous(krb5_context context, krb5_const_principal principal)
{
return krb5_principal_is_anonymous(context, principal, KRB5_ANON_MATCH_ANY);
}
static int
require_preauth_p(kdc_request_t r)
{
return r->config->require_preauth
|| r->client->entry.flags.require_preauth
|| r->server->entry.flags.require_preauth;
}
/*
*
*/
static krb5_error_code
add_enc_pa_rep(kdc_request_t r)
{
krb5_error_code ret;
krb5_crypto crypto;
Checksum checksum;
krb5_data cdata;
size_t len;
ret = krb5_crypto_init(r->context, &r->reply_key, 0, &crypto);
if (ret)
return ret;
ret = krb5_create_checksum(r->context, crypto,
KRB5_KU_AS_REQ, 0,
r->request.data, r->request.length,
&checksum);
krb5_crypto_destroy(r->context, crypto);
if (ret)
return ret;
ASN1_MALLOC_ENCODE(Checksum, cdata.data, cdata.length,
&checksum, &len, ret);
free_Checksum(&checksum);
if (ret)
return ret;
heim_assert(cdata.length == len, "ASN.1 internal error");
if (r->ek.encrypted_pa_data == NULL) {
ALLOC(r->ek.encrypted_pa_data);
if (r->ek.encrypted_pa_data == NULL)
return ENOMEM;
}
ret = krb5_padata_add(r->context, r->ek.encrypted_pa_data,
KRB5_PADATA_REQ_ENC_PA_REP, cdata.data, cdata.length);
if (ret)
return ret;
return krb5_padata_add(r->context, r->ek.encrypted_pa_data,
KRB5_PADATA_FX_FAST, NULL, 0);
}
/*
*
*/
krb5_error_code
_kdc_as_rep(kdc_request_t r,
krb5_data *reply,
const char *from,
struct sockaddr *from_addr,
int datagram_reply)
{
krb5_context context = r->context;
krb5_kdc_configuration *config = r->config;
KDC_REQ *req = &r->req;
KDC_REQ_BODY *b = NULL;
AS_REP rep;
KDCOptions f;
krb5_enctype setype;
krb5_error_code ret = 0;
Key *skey;
int found_pa = 0;
int i, flags = HDB_F_FOR_AS_REQ;
METHOD_DATA error_method;
const PA_DATA *pa;
memset(&rep, 0, sizeof(rep));
error_method.len = 0;
error_method.val = NULL;
/*
* Look for FAST armor and unwrap
*/
ret = _kdc_fast_unwrap_request(r);
if (ret) {
_kdc_r_log(r, 0, "FAST unwrap request from %s failed: %d", from, ret);
goto out;
}
b = &req->req_body;
f = b->kdc_options;
if (f.canonicalize)
flags |= HDB_F_CANON;
if(b->sname == NULL){
ret = KRB5KRB_ERR_GENERIC;
_kdc_set_e_text(r, "No server in request");
} else{
ret = _krb5_principalname2krb5_principal (context,
&r->server_princ,
*(b->sname),
b->realm);
if (ret == 0)
ret = krb5_unparse_name(context, r->server_princ, &r->server_name);
}
if (ret) {
kdc_log(context, config, 0,
"AS-REQ malformed server name from %s", from);
goto out;
}
if(b->cname == NULL){
ret = KRB5KRB_ERR_GENERIC;
_kdc_set_e_text(r, "No client in request");
} else {
ret = _krb5_principalname2krb5_principal (context,
&r->client_princ,
*(b->cname),
b->realm);
if (ret)
goto out;
ret = krb5_unparse_name(context, r->client_princ, &r->client_name);
}
if (ret) {
kdc_log(context, config, 0,
"AS-REQ malformed client name from %s", from);
goto out;
}
kdc_log(context, config, 0, "AS-REQ %s from %s for %s",
r->client_name, from, r->server_name);
/*
*
*/
if (_kdc_is_anonymous(context, r->client_princ) &&
!_kdc_is_anon_request(&r->req)) {
kdc_log(context, config, 0, "Anonymous client w/o anonymous flag");
ret = KRB5KDC_ERR_BADOPTION;
goto out;
}
/*
*
*/
ret = _kdc_db_fetch(context, config, r->client_princ,
HDB_F_GET_CLIENT | flags, NULL,
&r->clientdb, &r->client);
if(ret == HDB_ERR_NOT_FOUND_HERE) {
kdc_log(context, config, 5, "client %s does not have secrets at this KDC, need to proxy",
r->client_name);
goto out;
} else if (ret == HDB_ERR_WRONG_REALM) {
char *fixed_client_name = NULL;
ret = krb5_unparse_name(context, r->client->entry.principal,
&fixed_client_name);
if (ret) {
goto out;
}
kdc_log(context, config, 0, "WRONG_REALM - %s -> %s",
r->client_name, fixed_client_name);
free(fixed_client_name);
ret = _kdc_fast_mk_error(context, r,
&error_method,
r->armor_crypto,
&req->req_body,
KRB5_KDC_ERR_WRONG_REALM,
NULL,
r->server_princ,
NULL,
&r->client->entry.principal->realm,
NULL, NULL,
reply);
goto out;
} else if(ret){
const char *msg = krb5_get_error_message(context, ret);
kdc_log(context, config, 0, "UNKNOWN -- %s: %s", r->client_name, msg);
krb5_free_error_message(context, msg);
ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN;
goto out;
}
ret = _kdc_db_fetch(context, config, r->server_princ,
HDB_F_GET_SERVER|HDB_F_GET_KRBTGT | flags,
NULL, NULL, &r->server);
if(ret == HDB_ERR_NOT_FOUND_HERE) {
kdc_log(context, config, 5, "target %s does not have secrets at this KDC, need to proxy",
r->server_name);
goto out;
} else if(ret){
const char *msg = krb5_get_error_message(context, ret);
kdc_log(context, config, 0, "UNKNOWN -- %s: %s", r->server_name, msg);
krb5_free_error_message(context, msg);
ret = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN;
goto out;
}
/*
* Select a session enctype from the list of the crypto system
* supported enctypes that is supported by the client and is one of
* the enctype of the enctype of the service (likely krbtgt).
*
* The latter is used as a hint of what enctypes all KDC support,
* to make sure a newer version of KDC won't generate a session
* enctype that an older version of a KDC in the same realm can't
* decrypt.
*/
ret = _kdc_find_etype(context,
krb5_principal_is_krbtgt(context, r->server_princ) ?
config->tgt_use_strongest_session_key :
config->svc_use_strongest_session_key, FALSE,
r->client, b->etype.val, b->etype.len, &r->sessionetype,
NULL);
if (ret) {
kdc_log(context, config, 0,
"Client (%s) from %s has no common enctypes with KDC "
"to use for the session key",
r->client_name, from);
goto out;
}
/*
* Pre-auth processing
*/
if(req->padata){
unsigned int n;
log_patypes(context, config, req->padata);
/* Check if preauth matching */
for (n = 0; !found_pa && n < sizeof(pat) / sizeof(pat[0]); n++) {
if (pat[n].validate == NULL)
continue;
if (r->armor_crypto == NULL && (pat[n].flags & PA_REQ_FAST))
continue;
kdc_log(context, config, 5,
"Looking for %s pa-data -- %s", pat[n].name, r->client_name);
i = 0;
pa = _kdc_find_padata(req, &i, pat[n].type);
if (pa) {
ret = pat[n].validate(r, pa);
if (ret != 0) {
goto out;
}
kdc_log(context, config, 0,
"%s pre-authentication succeeded -- %s",
pat[n].name, r->client_name);
found_pa = 1;
r->et.flags.pre_authent = 1;
}
}
}
if (found_pa == 0) {
Key *ckey = NULL;
size_t n;
for (n = 0; n < sizeof(pat) / sizeof(pat[0]); n++) {
if ((pat[n].flags & PA_ANNOUNCE) == 0)
continue;
ret = krb5_padata_add(context, &error_method,
pat[n].type, NULL, 0);
if (ret)
goto out;
}
/*
* If there is a client key, send ETYPE_INFO{,2}
*/
ret = _kdc_find_etype(context,
config->preauth_use_strongest_session_key, TRUE,
r->client, b->etype.val, b->etype.len, NULL, &ckey);
if (ret == 0) {
/*
* RFC4120 requires:
* - If the client only knows about old enctypes, then send
* both info replies (we send 'info' first in the list).
* - If the client is 'modern', because it knows about 'new'
* enctype types, then only send the 'info2' reply.
*
* Before we send the full list of etype-info data, we pick
* the client key we would have used anyway below, just pick
* that instead.
*/
if (older_enctype(ckey->key.keytype)) {
ret = get_pa_etype_info(context, config,
&error_method, ckey);
if (ret)
goto out;
}
ret = get_pa_etype_info2(context, config,
&error_method, ckey);
if (ret)
goto out;
}
/*
* send requre preauth is its required or anon is requested,
* anon is today only allowed via preauth mechanisms.
*/
if (require_preauth_p(r) || _kdc_is_anon_request(&r->req)) {
ret = KRB5KDC_ERR_PREAUTH_REQUIRED;
_kdc_set_e_text(r, "Need to use PA-ENC-TIMESTAMP/PA-PK-AS-REQ");
goto out;
}
if (ckey == NULL) {
ret = KRB5KDC_ERR_CLIENT_NOTYET;
_kdc_set_e_text(r, "Doesn't have a client key available");
goto out;
}
krb5_free_keyblock_contents(r->context, &r->reply_key);
ret = krb5_copy_keyblock_contents(r->context, &ckey->key, &r->reply_key);
if (ret)
goto out;
}
if (r->clientdb->hdb_auth_status) {
r->clientdb->hdb_auth_status(context, r->clientdb, r->client,
HDB_AUTH_SUCCESS);
}
/*
* Verify flags after the user been required to prove its identity
* with in a preauth mech.
*/
ret = _kdc_check_access(context, config, r->client, r->client_name,
r->server, r->server_name,
req, &error_method);
if(ret)
goto out;
if (_kdc_is_anon_request(&r->req)) {
ret = _kdc_check_anon_policy(context, config, r->client, r->server);
if (ret) {
_kdc_set_e_text(r, "Anonymous ticket requests are disabled");
goto out;
}
r->et.flags.anonymous = 1;
}
/*
* Select the best encryption type for the KDC with out regard to
* the client since the client never needs to read that data.
*/
ret = _kdc_get_preferred_key(context, config,
r->server, r->server_name,
&setype, &skey);
if(ret)
goto out;
if(f.renew || f.validate || f.proxy || f.forwarded || f.enc_tkt_in_skey) {
ret = KRB5KDC_ERR_BADOPTION;
_kdc_set_e_text(r, "Bad KDC options");
goto out;
}
/*
* Build reply
*/
rep.pvno = 5;
rep.msg_type = krb_as_rep;
if (!config->historical_anon_realm &&
_kdc_is_anonymous(context, r->client_princ)) {
Realm anon_realm = KRB5_ANON_REALM;
ret = copy_Realm(&anon_realm, &rep.crealm);
} else
ret = copy_Realm(&r->client->entry.principal->realm, &rep.crealm);
if (ret)
goto out;
if (r->et.flags.anonymous)
ret = _kdc_make_anonymous_principalname(&rep.cname);
else
ret = _krb5_principal2principalname(&rep.cname, r->client->entry.principal);
if (ret)
goto out;
rep.ticket.tkt_vno = 5;
ret = copy_Realm(&r->server->entry.principal->realm, &rep.ticket.realm);
if (ret)
goto out;
_krb5_principal2principalname(&rep.ticket.sname,
r->server->entry.principal);
/* java 1.6 expects the name to be the same type, lets allow that
* uncomplicated name-types. */
#define CNT(sp,t) (((sp)->sname->name_type) == KRB5_NT_##t)
if (CNT(b, UNKNOWN) || CNT(b, PRINCIPAL) || CNT(b, SRV_INST) || CNT(b, SRV_HST) || CNT(b, SRV_XHST))
rep.ticket.sname.name_type = b->sname->name_type;
#undef CNT
r->et.flags.initial = 1;
if(r->client->entry.flags.forwardable && r->server->entry.flags.forwardable)
r->et.flags.forwardable = f.forwardable;
else if (f.forwardable) {
_kdc_set_e_text(r, "Ticket may not be forwardable");
ret = KRB5KDC_ERR_POLICY;
goto out;
}
if(r->client->entry.flags.proxiable && r->server->entry.flags.proxiable)
r->et.flags.proxiable = f.proxiable;
else if (f.proxiable) {
_kdc_set_e_text(r, "Ticket may not be proxiable");
ret = KRB5KDC_ERR_POLICY;
goto out;
}
if(r->client->entry.flags.postdate && r->server->entry.flags.postdate)
r->et.flags.may_postdate = f.allow_postdate;
else if (f.allow_postdate){
_kdc_set_e_text(r, "Ticket may not be postdate");
ret = KRB5KDC_ERR_POLICY;
goto out;
}
/* check for valid set of addresses */
if(!_kdc_check_addresses(context, config, b->addresses, from_addr)) {
_kdc_set_e_text(r, "Bad address list in requested");
ret = KRB5KRB_AP_ERR_BADADDR;
goto out;
}
ret = copy_PrincipalName(&rep.cname, &r->et.cname);
if (ret)
goto out;
ret = copy_Realm(&rep.crealm, &r->et.crealm);
if (ret)
goto out;
{
time_t start;
time_t t;
start = r->et.authtime = kdc_time;
if(f.postdated && req->req_body.from){
ALLOC(r->et.starttime);
start = *r->et.starttime = *req->req_body.from;
r->et.flags.invalid = 1;
r->et.flags.postdated = 1; /* XXX ??? */
}
_kdc_fix_time(&b->till);
t = *b->till;
/* be careful not overflowing */
if(r->client->entry.max_life)
t = start + min(t - start, *r->client->entry.max_life);
if(r->server->entry.max_life)
t = start + min(t - start, *r->server->entry.max_life);
#if 0
t = min(t, start + realm->max_life);
#endif
r->et.endtime = t;
if(f.renewable_ok && r->et.endtime < *b->till){
f.renewable = 1;
if(b->rtime == NULL){
ALLOC(b->rtime);
*b->rtime = 0;
}
if(*b->rtime < *b->till)
*b->rtime = *b->till;
}
if(f.renewable && b->rtime){
t = *b->rtime;
if(t == 0)
t = MAX_TIME;
if(r->client->entry.max_renew)
t = start + min(t - start, *r->client->entry.max_renew);
if(r->server->entry.max_renew)
t = start + min(t - start, *r->server->entry.max_renew);
#if 0
t = min(t, start + realm->max_renew);
#endif
ALLOC(r->et.renew_till);
*r->et.renew_till = t;
r->et.flags.renewable = 1;
}
}
if(b->addresses){
ALLOC(r->et.caddr);
copy_HostAddresses(b->addresses, r->et.caddr);
}
r->et.transited.tr_type = DOMAIN_X500_COMPRESS;
krb5_data_zero(&r->et.transited.contents);
/* The MIT ASN.1 library (obviously) doesn't tell lengths encoded
* as 0 and as 0x80 (meaning indefinite length) apart, and is thus
* incapable of correctly decoding SEQUENCE OF's of zero length.
*
* To fix this, always send at least one no-op last_req
*
* If there's a pw_end or valid_end we will use that,
* otherwise just a dummy lr.
*/
r->ek.last_req.val = malloc(2 * sizeof(*r->ek.last_req.val));
if (r->ek.last_req.val == NULL) {
ret = ENOMEM;
goto out;
}
r->ek.last_req.len = 0;
if (r->client->entry.pw_end
&& (config->kdc_warn_pwexpire == 0
|| kdc_time + config->kdc_warn_pwexpire >= *r->client->entry.pw_end)) {
r->ek.last_req.val[r->ek.last_req.len].lr_type = LR_PW_EXPTIME;
r->ek.last_req.val[r->ek.last_req.len].lr_value = *r->client->entry.pw_end;
++r->ek.last_req.len;
}
if (r->client->entry.valid_end) {
r->ek.last_req.val[r->ek.last_req.len].lr_type = LR_ACCT_EXPTIME;
r->ek.last_req.val[r->ek.last_req.len].lr_value = *r->client->entry.valid_end;
++r->ek.last_req.len;
}
if (r->ek.last_req.len == 0) {
r->ek.last_req.val[r->ek.last_req.len].lr_type = LR_NONE;
r->ek.last_req.val[r->ek.last_req.len].lr_value = 0;
++r->ek.last_req.len;
}
r->ek.nonce = b->nonce;
if (r->client->entry.valid_end || r->client->entry.pw_end) {
ALLOC(r->ek.key_expiration);
if (r->client->entry.valid_end) {
if (r->client->entry.pw_end)
*r->ek.key_expiration = min(*r->client->entry.valid_end,
*r->client->entry.pw_end);
else
*r->ek.key_expiration = *r->client->entry.valid_end;
} else
*r->ek.key_expiration = *r->client->entry.pw_end;
} else
r->ek.key_expiration = NULL;
r->ek.flags = r->et.flags;
r->ek.authtime = r->et.authtime;
if (r->et.starttime) {
ALLOC(r->ek.starttime);
*r->ek.starttime = *r->et.starttime;
}
r->ek.endtime = r->et.endtime;
if (r->et.renew_till) {
ALLOC(r->ek.renew_till);
*r->ek.renew_till = *r->et.renew_till;
}
ret = copy_Realm(&rep.ticket.realm, &r->ek.srealm);
if (ret)
goto out;
ret = copy_PrincipalName(&rep.ticket.sname, &r->ek.sname);
if (ret)
goto out;
if(r->et.caddr){
ALLOC(r->ek.caddr);
copy_HostAddresses(r->et.caddr, r->ek.caddr);
}
/*
* Check and session and reply keys
*/
if (r->session_key.keytype == ETYPE_NULL) {
ret = krb5_generate_random_keyblock(context, r->sessionetype, &r->session_key);
if (ret)
goto out;
}
if (r->reply_key.keytype == ETYPE_NULL) {
_kdc_set_e_text(r, "Client have no reply key");
ret = KRB5KDC_ERR_CLIENT_NOTYET;
goto out;
}
ret = copy_EncryptionKey(&r->session_key, &r->et.key);
if (ret)
goto out;
ret = copy_EncryptionKey(&r->session_key, &r->ek.key);
if (ret)
goto out;
if (r->outpadata.len) {
ALLOC(rep.padata);
if (rep.padata == NULL) {
ret = ENOMEM;
goto out;
}
ret = copy_METHOD_DATA(&r->outpadata, rep.padata);
if (ret)
goto out;
}
/* Add the PAC */
if (send_pac_p(context, req) && !r->et.flags.anonymous) {
generate_pac(r, skey);
}
_kdc_log_timestamp(context, config, "AS-REQ", r->et.authtime, r->et.starttime,
r->et.endtime, r->et.renew_till);
{
krb5_principal client_principal;
ret = _krb5_principalname2krb5_principal(context, &client_principal,
rep.cname, rep.crealm);
if (ret)
goto out;
/* do this as the last thing since this signs the EncTicketPart */
ret = _kdc_add_KRB5SignedPath(context,
config,
r->server,
setype,
client_principal,
NULL,
NULL,
&r->et);
krb5_free_principal(context, client_principal);
if (ret)
goto out;
}
log_as_req(context, config, r->reply_key.keytype, setype, b);
/*
* We always say we support FAST/enc-pa-rep
*/
r->et.flags.enc_pa_rep = r->ek.flags.enc_pa_rep = 1;
/*
* Add REQ_ENC_PA_REP if client supports it
*/
i = 0;
pa = _kdc_find_padata(req, &i, KRB5_PADATA_REQ_ENC_PA_REP);
if (pa) {
ret = add_enc_pa_rep(r);
if (ret) {
const char *msg = krb5_get_error_message(r->context, ret);
_kdc_r_log(r, 0, "add_enc_pa_rep failed: %s: %d", msg, ret);
krb5_free_error_message(r->context, msg);
goto out;
}
}
/*
*
*/
ret = _kdc_encode_reply(context, config,
r->armor_crypto, req->req_body.nonce,
&rep, &r->et, &r->ek, setype, r->server->entry.kvno,
&skey->key, r->client->entry.kvno,
&r->reply_key, 0, &r->e_text, reply);
if (ret)
goto out;
/*
* Check if message too large
*/
if (datagram_reply && reply->length > config->max_datagram_reply_length) {
krb5_data_free(reply);
ret = KRB5KRB_ERR_RESPONSE_TOO_BIG;
_kdc_set_e_text(r, "Reply packet too large");
}
out:
free_AS_REP(&rep);
/*
* In case of a non proxy error, build an error message.
*/
if (ret != 0 && ret != HDB_ERR_NOT_FOUND_HERE && reply->length == 0) {
ret = _kdc_fast_mk_error(context, r,
&error_method,
r->armor_crypto,
&req->req_body,
ret, r->e_text,
r->server_princ,
r->client_princ ?
&r->client_princ->name : NULL,
r->client_princ ?
&r->client_princ->realm : NULL,
NULL, NULL,
reply);
if (ret)
goto out2;
}
out2:
free_EncTicketPart(&r->et);
free_EncKDCRepPart(&r->ek);
free_KDCFastState(&r->fast);
if (error_method.len)
free_METHOD_DATA(&error_method);
if (r->outpadata.len)
free_METHOD_DATA(&r->outpadata);
if (r->client_princ) {
krb5_free_principal(context, r->client_princ);
r->client_princ = NULL;
}
if (r->client_name) {
free(r->client_name);
r->client_name = NULL;
}
if (r->server_princ){
krb5_free_principal(context, r->server_princ);
r->server_princ = NULL;
}
if (r->server_name) {
free(r->server_name);
r->server_name = NULL;
}
if (r->client)
_kdc_free_ent(context, r->client);
if (r->server)
_kdc_free_ent(context, r->server);
if (r->armor_crypto) {
krb5_crypto_destroy(r->context, r->armor_crypto);
r->armor_crypto = NULL;
}
krb5_free_keyblock_contents(r->context, &r->reply_key);
krb5_free_keyblock_contents(r->context, &r->session_key);
return ret;
}
/*
* Add the AuthorizationData `data´ of `type´ to the last element in
* the sequence of authorization_data in `tkt´ wrapped in an IF_RELEVANT
*/
krb5_error_code
_kdc_tkt_add_if_relevant_ad(krb5_context context,
EncTicketPart *tkt,
int type,
const krb5_data *data)
{
krb5_error_code ret;
size_t size = 0;
if (tkt->authorization_data == NULL) {
tkt->authorization_data = calloc(1, sizeof(*tkt->authorization_data));
if (tkt->authorization_data == NULL) {
krb5_set_error_message(context, ENOMEM, "out of memory");
return ENOMEM;
}
}
/* add the entry to the last element */
{
AuthorizationData ad = { 0, NULL };
AuthorizationDataElement ade;
ade.ad_type = type;
ade.ad_data = *data;
ret = add_AuthorizationData(&ad, &ade);
if (ret) {
krb5_set_error_message(context, ret, "add AuthorizationData failed");
return ret;
}
ade.ad_type = KRB5_AUTHDATA_IF_RELEVANT;
ASN1_MALLOC_ENCODE(AuthorizationData,
ade.ad_data.data, ade.ad_data.length,
&ad, &size, ret);
free_AuthorizationData(&ad);
if (ret) {
krb5_set_error_message(context, ret, "ASN.1 encode of "
"AuthorizationData failed");
return ret;
}
if (ade.ad_data.length != size)
krb5_abortx(context, "internal asn.1 encoder error");
ret = add_AuthorizationData(tkt->authorization_data, &ade);
der_free_octet_string(&ade.ad_data);
if (ret) {
krb5_set_error_message(context, ret, "add AuthorizationData failed");
return ret;
}
}
return 0;
}