/* Decrypt the ticket in req using the key in ent. */
static krb5_error_code
try_one_entry(krb5_context context, const krb5_ap_req *req,
krb5_keytab_entry *ent, krb5_keyblock *keyblock_out)
{
krb5_error_code ret;
krb5_principal tmp = NULL;
/* Try decrypting the ticket with this entry's key. */
ret = krb5_decrypt_tkt_part(context, &ent->key, req->ticket);
if (ret)
return ret;
/* Make a copy of the principal for the ticket server field. */
ret = krb5_copy_principal(context, ent->principal, &tmp);
if (ret)
return ret;
/* Make a copy of the decrypting key if requested by the caller. */
if (keyblock_out != NULL) {
ret = krb5_copy_keyblock_contents(context, &ent->key, keyblock_out);
if (ret) {
krb5_free_principal(context, tmp);
return ret;
}
}
/* Make req->ticket->server indicate the actual server principal. */
krb5_free_principal(context, req->ticket->server);
req->ticket->server = tmp;
return 0;
}
krb5_error_code KRB5_CALLCONV
krb5int_server_decrypt_ticket_keyblock(krb5_context context,
const krb5_keyblock *key,
krb5_ticket *ticket)
{
krb5_error_code retval;
krb5_data *realm;
krb5_transited *trans;
retval = krb5_decrypt_tkt_part(context, key, ticket);
if (retval)
goto done;
trans = &ticket->enc_part2->transited;
realm = &ticket->enc_part2->client->realm;
if (trans->tr_contents.data && *trans->tr_contents.data) {
retval = krb5_check_transited_list(context, &trans->tr_contents,
realm, &ticket->server->realm);
goto done;
}
if (ticket->enc_part2->flags & TKT_FLG_INVALID) { /* ie, KDC_OPT_POSTDATED */
retval = KRB5KRB_AP_ERR_TKT_INVALID;
goto done;
}
done:
return retval;
}
/*
* AIX krb5 has krb5_decrypt_tkt_part, but no krb5_c_decrypt. So, implement our
* own krb5_c_decrypt. Note that this krb5_c_decrypt is only suitable for
* decrypting an encrypted krb5_enc_tkt_part. But since that's all we ever use
* it for, that should be fine.
*/
static krb5_error_code
krb5_c_decrypt(krb5_context context, const krb5_keyblock *key,
krb5_keyusage usage, const krb5_data *cipher_state,
const krb5_enc_data *input, krb5_data *output)
{
krb5_ticket tkt;
krb5_error_code code;
krb5_data *tout = NULL;
/* We only handle a subset of possible arguments; if we somehow get passed
* something else, bail out with EINVAL. */
if (cipher_state != NULL)
return EINVAL;
if (usage != KRB5_KEYUSAGE_KDC_REP_TICKET)
return EINVAL;
memset(&tkt, 0, sizeof(tkt));
tkt.enc_part = *input;
code = krb5_decrypt_tkt_part(context, key, &tkt);
if (code != 0)
return code;
code = encode_krb5_enc_tkt_part(tkt.enc_part2, &tout);
if (code != 0)
return code;
if (tout->length > output->length) {
/* This should never happen, but don't assert since we may be dealing
* with untrusted user data. */
code = EINVAL;
goto error;
}
memcpy(output->data, tout->data, tout->length);
output->length = tout->length;
error:
if (tout)
krb5_free_data(context, tout);
return code;
}
static krb5_error_code
krb5_rd_req_decrypt_tkt_part(krb5_context context, const krb5_ap_req *req, krb5_keytab keytab)
{
krb5_error_code retval;
krb5_enctype enctype;
krb5_keytab_entry ktent;
enctype = req->ticket->enc_part.enctype;
if ((retval = krb5_kt_get_entry(context, keytab, req->ticket->server,
req->ticket->enc_part.kvno,
enctype, &ktent)))
return retval;
retval = krb5_decrypt_tkt_part(context, &ktent.key, req->ticket);
/* Upon error, Free keytab entry first, then return */
(void) krb5_kt_free_entry(context, &ktent);
return retval;
}
/*
* Get the key for the second ticket, if any, and decrypt it.
*/
static krb5_error_code
decrypt_2ndtkt(kdc_realm_t *kdc_active_realm, krb5_kdc_req *req,
krb5_flags flags, krb5_db_entry **server_out,
const char **status)
{
krb5_error_code retval;
krb5_db_entry *server;
krb5_keyblock *key;
krb5_kvno kvno;
krb5_ticket *stkt;
if (!(req->kdc_options & STKT_OPTIONS))
return 0;
stkt = req->second_ticket[0];
retval = kdc_get_server_key(kdc_context, stkt,
flags,
TRUE, /* match_enctype */
&server,
&key,
&kvno);
if (retval != 0) {
*status = "2ND_TKT_SERVER";
goto cleanup;
}
retval = krb5_decrypt_tkt_part(kdc_context, key,
req->second_ticket[0]);
krb5_free_keyblock(kdc_context, key);
if (retval != 0) {
*status = "2ND_TKT_DECRYPT";
goto cleanup;
}
*server_out = server;
cleanup:
return retval;
}
static krb5_error_code
krb5_rd_req_decoded_opt(krb5_context context, krb5_auth_context *auth_context,
const krb5_ap_req *req, krb5_const_principal server,
krb5_keytab keytab, krb5_flags *ap_req_options,
krb5_ticket **ticket, int check_valid_flag)
{
krb5_error_code retval = 0;
krb5_timestamp currenttime;
krb5_principal_data princ_data;
req->ticket->enc_part2 == NULL;
if (server && krb5_is_referral_realm(&server->realm)) {
char *realm;
princ_data = *server;
server = &princ_data;
retval = krb5_get_default_realm(context, &realm);
if (retval)
return retval;
princ_data.realm.data = realm;
princ_data.realm.length = strlen(realm);
}
if (server && !krb5_principal_compare(context, server, req->ticket->server)) {
char *found_name = 0, *wanted_name = 0;
if (krb5_unparse_name(context, server, &wanted_name) == 0
&& krb5_unparse_name(context, req->ticket->server, &found_name) == 0)
krb5_set_error_message(context, KRB5KRB_AP_WRONG_PRINC,
"Wrong principal in request (found %s, wanted %s)",
found_name, wanted_name);
krb5_free_unparsed_name(context, wanted_name);
krb5_free_unparsed_name(context, found_name);
retval = KRB5KRB_AP_WRONG_PRINC;
goto cleanup;
}
/* if (req->ap_options & AP_OPTS_USE_SESSION_KEY)
do we need special processing here ? */
/* decrypt the ticket */
if ((*auth_context)->keyblock) { /* User to User authentication */
if ((retval = krb5_decrypt_tkt_part(context, (*auth_context)->keyblock,
req->ticket)))
goto cleanup;
krb5_free_keyblock(context, (*auth_context)->keyblock);
(*auth_context)->keyblock = NULL;
} else {
if ((retval = krb5_rd_req_decrypt_tkt_part(context, req, keytab)))
goto cleanup;
}
/* XXX this is an evil hack. check_valid_flag is set iff the call
is not from inside the kdc. we can use this to determine which
key usage to use */
if ((retval = decrypt_authenticator(context, req,
&((*auth_context)->authentp),
check_valid_flag)))
goto cleanup;
if (!krb5_principal_compare(context, (*auth_context)->authentp->client,
req->ticket->enc_part2->client)) {
retval = KRB5KRB_AP_ERR_BADMATCH;
goto cleanup;
}
if ((*auth_context)->remote_addr &&
!krb5_address_search(context, (*auth_context)->remote_addr,
req->ticket->enc_part2->caddrs)) {
retval = KRB5KRB_AP_ERR_BADADDR;
goto cleanup;
}
/* okay, now check cross-realm policy */
#if defined(_SINGLE_HOP_ONLY)
/* Single hop cross-realm tickets only */
{
krb5_transited *trans = &(req->ticket->enc_part2->transited);
/* If the transited list is empty, then we have at most one hop */
if (trans->tr_contents.data && trans->tr_contents.data[0])
retval = KRB5KRB_AP_ERR_ILL_CR_TKT;
}
#elif defined(_NO_CROSS_REALM)
/* No cross-realm tickets */
{
char * lrealm;
krb5_data * realm;
krb5_transited * trans;
realm = krb5_princ_realm(context, req->ticket->enc_part2->client);
trans = &(req->ticket->enc_part2->transited);
/*
* If the transited list is empty, then we have at most one hop
* So we also have to check that the client's realm is the local one
*/
krb5_get_default_realm(context, &lrealm);
if ((trans->tr_contents.data && trans->tr_contents.data[0]) ||
strlen(lrealm) != realm->length ||
memcmp(lrealm, realm->data, strlen(lrealm))) {
retval = KRB5KRB_AP_ERR_ILL_CR_TKT;
}
free(lrealm);
}
#else
/* Hierarchical Cross-Realm */
{
krb5_data * realm;
krb5_transited * trans;
realm = krb5_princ_realm(context, req->ticket->enc_part2->client);
trans = &(req->ticket->enc_part2->transited);
/*
* If the transited list is not empty, then check that all realms
* transited are within the hierarchy between the client's realm
* and the local realm.
*/
if (trans->tr_contents.data && trans->tr_contents.data[0]) {
retval = krb5_check_transited_list(context, &(trans->tr_contents),
realm,
krb5_princ_realm (context,
server));
}
}
#endif
if (retval) goto cleanup;
/* only check rcache if sender has provided one---some services
may not be able to use replay caches (such as datagram servers) */
if ((*auth_context)->rcache) {
krb5_donot_replay rep;
krb5_tkt_authent tktauthent;
tktauthent.ticket = req->ticket;
tktauthent.authenticator = (*auth_context)->authentp;
if (!(retval = krb5_auth_to_rep(context, &tktauthent, &rep))) {
retval = krb5_rc_store(context, (*auth_context)->rcache, &rep);
krb5_xfree(rep.server);
krb5_xfree(rep.client);
}
if (retval)
goto cleanup;
}
retval = krb5_validate_times(context, &req->ticket->enc_part2->times);
if (retval != 0)
goto cleanup;
if ((retval = krb5_timeofday(context, ¤ttime)))
goto cleanup;
if (!in_clock_skew((*auth_context)->authentp->ctime)) {
retval = KRB5KRB_AP_ERR_SKEW;
goto cleanup;
}
if (check_valid_flag) {
if (req->ticket->enc_part2->flags & TKT_FLG_INVALID) {
retval = KRB5KRB_AP_ERR_TKT_INVALID;
goto cleanup;
}
}
/* check if the various etypes are permitted */
if ((*auth_context)->auth_context_flags & KRB5_AUTH_CONTEXT_PERMIT_ALL) {
/* no etype check needed */;
} else if ((*auth_context)->permitted_etypes == NULL) {
int etype;
/* check against the default set */
if ((!krb5_is_permitted_enctype(context,
etype = req->ticket->enc_part.enctype)) ||
(!krb5_is_permitted_enctype(context,
etype = req->ticket->enc_part2->session->enctype)) ||
(((*auth_context)->authentp->subkey) &&
!krb5_is_permitted_enctype(context,
etype = (*auth_context)->authentp->subkey->enctype))) {
char enctype_name[30];
retval = KRB5_NOPERM_ETYPE;
if (krb5_enctype_to_string(etype, enctype_name, sizeof(enctype_name)) == 0)
krb5_set_error_message(context, retval,
"Encryption type %s not permitted",
enctype_name);
goto cleanup;
}
} else {
/* check against the set in the auth_context */
int i;
for (i=0; (*auth_context)->permitted_etypes[i]; i++)
if ((*auth_context)->permitted_etypes[i] ==
req->ticket->enc_part.enctype)
break;
if (!(*auth_context)->permitted_etypes[i]) {
char enctype_name[30];
retval = KRB5_NOPERM_ETYPE;
if (krb5_enctype_to_string(req->ticket->enc_part.enctype,
enctype_name, sizeof(enctype_name)) == 0)
krb5_set_error_message(context, retval,
"Encryption type %s not permitted",
enctype_name);
goto cleanup;
}
for (i=0; (*auth_context)->permitted_etypes[i]; i++)
if ((*auth_context)->permitted_etypes[i] ==
req->ticket->enc_part2->session->enctype)
break;
if (!(*auth_context)->permitted_etypes[i]) {
char enctype_name[30];
retval = KRB5_NOPERM_ETYPE;
if (krb5_enctype_to_string(req->ticket->enc_part2->session->enctype,
enctype_name, sizeof(enctype_name)) == 0)
krb5_set_error_message(context, retval,
"Encryption type %s not permitted",
enctype_name);
goto cleanup;
}
if ((*auth_context)->authentp->subkey) {
for (i=0; (*auth_context)->permitted_etypes[i]; i++)
if ((*auth_context)->permitted_etypes[i] ==
(*auth_context)->authentp->subkey->enctype)
break;
if (!(*auth_context)->permitted_etypes[i]) {
char enctype_name[30];
retval = KRB5_NOPERM_ETYPE;
if (krb5_enctype_to_string((*auth_context)->authentp->subkey->enctype,
enctype_name,
sizeof(enctype_name)) == 0)
krb5_set_error_message(context, retval,
"Encryption type %s not permitted",
enctype_name);
goto cleanup;
}
}
}
(*auth_context)->remote_seq_number = (*auth_context)->authentp->seq_number;
if ((*auth_context)->authentp->subkey) {
if ((retval = krb5_copy_keyblock(context,
(*auth_context)->authentp->subkey,
&((*auth_context)->recv_subkey))))
goto cleanup;
retval = krb5_copy_keyblock(context, (*auth_context)->authentp->subkey,
&((*auth_context)->send_subkey));
if (retval) {
krb5_free_keyblock(context, (*auth_context)->recv_subkey);
(*auth_context)->recv_subkey = NULL;
goto cleanup;
}
} else {
(*auth_context)->recv_subkey = 0;
(*auth_context)->send_subkey = 0;
}
if ((retval = krb5_copy_keyblock(context, req->ticket->enc_part2->session,
&((*auth_context)->keyblock))))
goto cleanup;
/*
* If not AP_OPTS_MUTUAL_REQUIRED then and sequence numbers are used
* then the default sequence number is the one's complement of the
* sequence number sent ot us.
*/
if ((!(req->ap_options & AP_OPTS_MUTUAL_REQUIRED)) &&
(*auth_context)->remote_seq_number) {
(*auth_context)->local_seq_number ^=
(*auth_context)->remote_seq_number;
}
if (ticket)
if ((retval = krb5_copy_ticket(context, req->ticket, ticket)))
goto cleanup;
if (ap_req_options)
*ap_req_options = req->ap_options;
retval = 0;
cleanup:
if (server == &princ_data)
krb5_free_default_realm(context, princ_data.realm.data);
if (retval) {
/* only free if we're erroring out...otherwise some
applications will need the output. */
if (req->ticket->enc_part2)
krb5_free_enc_tkt_part(context, req->ticket->enc_part2);
req->ticket->enc_part2 = NULL;
}
return retval;
}
/*ARGSUSED*/
krb5_error_code
process_tgs_req(krb5_data *pkt, const krb5_fulladdr *from,
krb5_data **response)
{
krb5_keyblock * subkey = 0;
krb5_kdc_req *request = 0;
krb5_db_entry server;
krb5_kdc_rep reply;
krb5_enc_kdc_rep_part reply_encpart;
krb5_ticket ticket_reply, *header_ticket = 0;
int st_idx = 0;
krb5_enc_tkt_part enc_tkt_reply;
krb5_transited enc_tkt_transited;
int newtransited = 0;
krb5_error_code retval = 0;
krb5_keyblock encrypting_key;
int nprincs = 0;
krb5_boolean more;
krb5_timestamp kdc_time, authtime=0;
krb5_keyblock session_key;
krb5_timestamp until, rtime;
krb5_keyblock *reply_key = NULL;
krb5_keyblock *mkey_ptr;
krb5_key_data *server_key;
char *cname = 0, *sname = 0, *altcname = 0;
krb5_last_req_entry *nolrarray[2], nolrentry;
krb5_enctype useenctype;
int errcode, errcode2;
register int i;
int firstpass = 1;
const char *status = 0;
krb5_enc_tkt_part *header_enc_tkt = NULL; /* ticket granting or evidence ticket */
krb5_db_entry client, krbtgt;
int c_nprincs = 0, k_nprincs = 0;
krb5_pa_s4u_x509_user *s4u_x509_user = NULL; /* protocol transition request */
krb5_authdata **kdc_issued_auth_data = NULL; /* auth data issued by KDC */
unsigned int c_flags = 0, s_flags = 0; /* client/server KDB flags */
char *s4u_name = NULL;
krb5_boolean is_referral, db_ref_done = FALSE;
const char *emsg = NULL;
krb5_data *tgs_1 =NULL, *server_1 = NULL;
krb5_principal krbtgt_princ;
krb5_kvno ticket_kvno = 0;
struct kdc_request_state *state = NULL;
krb5_pa_data *pa_tgs_req; /*points into request*/
krb5_data scratch;
session_key.contents = NULL;
retval = decode_krb5_tgs_req(pkt, &request);
if (retval)
return retval;
/*
* setup_server_realm() sets up the global realm-specific data pointer.
*/
if ((retval = setup_server_realm(request->server))) {
krb5_free_kdc_req(kdc_context, request);
return retval;
}
errcode = kdc_process_tgs_req(request, from, pkt, &header_ticket,
&krbtgt, &k_nprincs, &subkey, &pa_tgs_req);
if (header_ticket && header_ticket->enc_part2 &&
(errcode2 = krb5_unparse_name(kdc_context,
header_ticket->enc_part2->client,
&cname))) {
status = "UNPARSING CLIENT";
errcode = errcode2;
goto cleanup;
}
limit_string(cname);
if (errcode) {
status = "PROCESS_TGS";
goto cleanup;
}
if (!header_ticket) {
errcode = KRB5_NO_TKT_SUPPLIED; /* XXX? */
status="UNEXPECTED NULL in header_ticket";
goto cleanup;
}
errcode = kdc_make_rstate(&state);
if (errcode !=0) {
status = "making state";
goto cleanup;
}
scratch.length = pa_tgs_req->length;
scratch.data = (char *) pa_tgs_req->contents;
errcode = kdc_find_fast(&request, &scratch, subkey, header_ticket->enc_part2->session, state);
if (errcode !=0) {
status = "kdc_find_fast";
goto cleanup;
}
/*
* Pointer to the encrypted part of the header ticket, which may be
* replaced to point to the encrypted part of the evidence ticket
* if constrained delegation is used. This simplifies the number of
* special cases for constrained delegation.
*/
header_enc_tkt = header_ticket->enc_part2;
/*
* We've already dealt with the AP_REQ authentication, so we can
* use header_ticket freely. The encrypted part (if any) has been
* decrypted with the session key.
*/
/* XXX make sure server here has the proper realm...taken from AP_REQ
header? */
if (isflagset(request->kdc_options, KDC_OPT_CANONICALIZE)) {
setflag(c_flags, KRB5_KDB_FLAG_CANONICALIZE);
setflag(s_flags, KRB5_KDB_FLAG_CANONICALIZE);
}
db_ref_done = FALSE;
ref_tgt_again:
nprincs = 1;
if ((errcode = krb5_unparse_name(kdc_context, request->server, &sname))) {
status = "UNPARSING SERVER";
goto cleanup;
}
limit_string(sname);
errcode = krb5_db_get_principal_ext(kdc_context,
request->server,
s_flags,
&server,
&nprincs,
&more);
if (errcode) {
status = "LOOKING_UP_SERVER";
nprincs = 0;
goto cleanup;
}
tgt_again:
if (more) {
status = "NON_UNIQUE_PRINCIPAL";
errcode = KRB5KDC_ERR_PRINCIPAL_NOT_UNIQUE;
goto cleanup;
} else if (nprincs != 1) {
/*
* might be a request for a TGT for some other realm; we
* should do our best to find such a TGS in this db
*/
if (firstpass ) {
if ( krb5_is_tgs_principal(request->server) == TRUE) { /* Principal is a name of krb ticket service */
if (krb5_princ_size(kdc_context, request->server) == 2) {
server_1 = krb5_princ_component(kdc_context, request->server, 1);
tgs_1 = krb5_princ_component(kdc_context, tgs_server, 1);
if (!tgs_1 || !data_eq(*server_1, *tgs_1)) {
krb5_db_free_principal(kdc_context, &server, nprincs);
find_alternate_tgs(request, &server, &more, &nprincs);
firstpass = 0;
goto tgt_again;
}
}
krb5_db_free_principal(kdc_context, &server, nprincs);
status = "UNKNOWN_SERVER";
errcode = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN;
goto cleanup;
} else if ( db_ref_done == FALSE) {
retval = prep_reprocess_req(request, &krbtgt_princ);
if (!retval) {
krb5_free_principal(kdc_context, request->server);
retval = krb5_copy_principal(kdc_context, krbtgt_princ, &(request->server));
if (!retval) {
db_ref_done = TRUE;
if (sname != NULL)
free(sname);
goto ref_tgt_again;
}
}
}
}
krb5_db_free_principal(kdc_context, &server, nprincs);
status = "UNKNOWN_SERVER";
errcode = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN;
goto cleanup;
}
if ((errcode = krb5_timeofday(kdc_context, &kdc_time))) {
status = "TIME_OF_DAY";
goto cleanup;
}
if ((retval = validate_tgs_request(request, server, header_ticket,
kdc_time, &status))) {
if (!status)
status = "UNKNOWN_REASON";
errcode = retval + ERROR_TABLE_BASE_krb5;
goto cleanup;
}
if (!is_local_principal(header_enc_tkt->client))
setflag(c_flags, KRB5_KDB_FLAG_CROSS_REALM);
is_referral = krb5_is_tgs_principal(server.princ) &&
!krb5_principal_compare(kdc_context, tgs_server, server.princ);
/* Check for protocol transition */
errcode = kdc_process_s4u2self_req(kdc_context,
request,
header_enc_tkt->client,
&server,
subkey,
header_enc_tkt->session,
kdc_time,
&s4u_x509_user,
&client,
&c_nprincs,
&status);
if (errcode)
goto cleanup;
if (s4u_x509_user != NULL)
setflag(c_flags, KRB5_KDB_FLAG_PROTOCOL_TRANSITION);
/*
* We pick the session keytype here....
*
* Some special care needs to be taken in the user-to-user
* case, since we don't know what keytypes the application server
* which is doing user-to-user authentication can support. We
* know that it at least must be able to support the encryption
* type of the session key in the TGT, since otherwise it won't be
* able to decrypt the U2U ticket! So we use that in preference
* to anything else.
*/
useenctype = 0;
if (isflagset(request->kdc_options, KDC_OPT_ENC_TKT_IN_SKEY |
KDC_OPT_CNAME_IN_ADDL_TKT)) {
krb5_keyblock * st_sealing_key;
krb5_kvno st_srv_kvno;
krb5_enctype etype;
krb5_db_entry st_client;
int st_nprincs = 0;
/*
* Get the key for the second ticket, and decrypt it.
*/
if ((errcode = kdc_get_server_key(request->second_ticket[st_idx],
c_flags,
TRUE, /* match_enctype */
&st_client,
&st_nprincs,
&st_sealing_key,
&st_srv_kvno))) {
status = "2ND_TKT_SERVER";
goto cleanup;
}
errcode = krb5_decrypt_tkt_part(kdc_context, st_sealing_key,
request->second_ticket[st_idx]);
krb5_free_keyblock(kdc_context, st_sealing_key);
if (errcode) {
status = "2ND_TKT_DECRYPT";
krb5_db_free_principal(kdc_context, &st_client, st_nprincs);
goto cleanup;
}
etype = request->second_ticket[st_idx]->enc_part2->session->enctype;
if (!krb5_c_valid_enctype(etype)) {
status = "BAD_ETYPE_IN_2ND_TKT";
errcode = KRB5KDC_ERR_ETYPE_NOSUPP;
krb5_db_free_principal(kdc_context, &st_client, st_nprincs);
goto cleanup;
}
for (i = 0; i < request->nktypes; i++) {
if (request->ktype[i] == etype) {
useenctype = etype;
break;
}
}
if (isflagset(request->kdc_options, KDC_OPT_CNAME_IN_ADDL_TKT)) {
/* Do constrained delegation protocol and authorization checks */
errcode = kdc_process_s4u2proxy_req(kdc_context,
request,
request->second_ticket[st_idx]->enc_part2,
&st_client,
header_ticket->enc_part2->client,
request->server,
&status);
if (errcode)
goto cleanup;
setflag(c_flags, KRB5_KDB_FLAG_CONSTRAINED_DELEGATION);
assert(krb5_is_tgs_principal(header_ticket->server));
/* From now on, use evidence ticket as header ticket */
header_enc_tkt = request->second_ticket[st_idx]->enc_part2;
assert(c_nprincs == 0); /* assured by kdc_process_s4u2self_req() */
client = st_client;
c_nprincs = st_nprincs;
} else {
/* "client" is not used for user2user */
krb5_db_free_principal(kdc_context, &st_client, st_nprincs);
}
}
/*
* Select the keytype for the ticket session key.
*/
if ((useenctype == 0) &&
(useenctype = select_session_keytype(kdc_context, &server,
request->nktypes,
request->ktype)) == 0) {
/* unsupported ktype */
status = "BAD_ENCRYPTION_TYPE";
errcode = KRB5KDC_ERR_ETYPE_NOSUPP;
goto cleanup;
}
errcode = krb5_c_make_random_key(kdc_context, useenctype, &session_key);
if (errcode) {
/* random key failed */
status = "RANDOM_KEY_FAILED";
goto cleanup;
}
authtime = header_enc_tkt->times.authtime;
if (is_referral)
ticket_reply.server = server.princ;
else
ticket_reply.server = request->server; /* XXX careful for realm... */
enc_tkt_reply.flags = 0;
enc_tkt_reply.times.starttime = 0;
if (isflagset(server.attributes, KRB5_KDB_OK_AS_DELEGATE))
setflag(enc_tkt_reply.flags, TKT_FLG_OK_AS_DELEGATE);
/*
* Fix header_ticket's starttime; if it's zero, fill in the
* authtime's value.
*/
if (!(header_enc_tkt->times.starttime))
header_enc_tkt->times.starttime = header_enc_tkt->times.authtime;
/* don't use new addresses unless forwarded, see below */
enc_tkt_reply.caddrs = header_enc_tkt->caddrs;
/* noaddrarray[0] = 0; */
reply_encpart.caddrs = 0;/* optional...don't put it in */
reply_encpart.enc_padata = NULL;
/* It should be noted that local policy may affect the */
/* processing of any of these flags. For example, some */
/* realms may refuse to issue renewable tickets */
if (isflagset(request->kdc_options, KDC_OPT_FORWARDABLE)) {
setflag(enc_tkt_reply.flags, TKT_FLG_FORWARDABLE);
if (isflagset(c_flags, KRB5_KDB_FLAG_PROTOCOL_TRANSITION)) {
/*
* If S4U2Self principal is not forwardable, then mark ticket as
* unforwardable. This behaviour matches Windows, but it is
* different to the MIT AS-REQ path, which returns an error
* (KDC_ERR_POLICY) if forwardable tickets cannot be issued.
*
* Consider this block the S4U2Self equivalent to
* validate_forwardable().
*/
if (c_nprincs &&
isflagset(client.attributes, KRB5_KDB_DISALLOW_FORWARDABLE))
clear(enc_tkt_reply.flags, TKT_FLG_FORWARDABLE);
/*
* OK_TO_AUTH_AS_DELEGATE must be set on the service requesting
* S4U2Self in order for forwardable tickets to be returned.
*/
else if (!is_referral &&
!isflagset(server.attributes, KRB5_KDB_OK_TO_AUTH_AS_DELEGATE))
clear(enc_tkt_reply.flags, TKT_FLG_FORWARDABLE);
}
}
if (isflagset(request->kdc_options, KDC_OPT_FORWARDED)) {
setflag(enc_tkt_reply.flags, TKT_FLG_FORWARDED);
/* include new addresses in ticket & reply */
enc_tkt_reply.caddrs = request->addresses;
reply_encpart.caddrs = request->addresses;
}
if (isflagset(header_enc_tkt->flags, TKT_FLG_FORWARDED))
setflag(enc_tkt_reply.flags, TKT_FLG_FORWARDED);
if (isflagset(request->kdc_options, KDC_OPT_PROXIABLE))
setflag(enc_tkt_reply.flags, TKT_FLG_PROXIABLE);
if (isflagset(request->kdc_options, KDC_OPT_PROXY)) {
setflag(enc_tkt_reply.flags, TKT_FLG_PROXY);
/* include new addresses in ticket & reply */
enc_tkt_reply.caddrs = request->addresses;
reply_encpart.caddrs = request->addresses;
}
if (isflagset(request->kdc_options, KDC_OPT_ALLOW_POSTDATE))
setflag(enc_tkt_reply.flags, TKT_FLG_MAY_POSTDATE);
if (isflagset(request->kdc_options, KDC_OPT_POSTDATED)) {
setflag(enc_tkt_reply.flags, TKT_FLG_POSTDATED);
setflag(enc_tkt_reply.flags, TKT_FLG_INVALID);
enc_tkt_reply.times.starttime = request->from;
} else
enc_tkt_reply.times.starttime = kdc_time;
if (isflagset(request->kdc_options, KDC_OPT_VALIDATE)) {
assert(isflagset(c_flags, KRB5_KDB_FLAGS_S4U) == 0);
/* BEWARE of allocation hanging off of ticket & enc_part2, it belongs
to the caller */
ticket_reply = *(header_ticket);
enc_tkt_reply = *(header_ticket->enc_part2);
clear(enc_tkt_reply.flags, TKT_FLG_INVALID);
}
if (isflagset(request->kdc_options, KDC_OPT_RENEW)) {
krb5_deltat old_life;
assert(isflagset(c_flags, KRB5_KDB_FLAGS_S4U) == 0);
/* BEWARE of allocation hanging off of ticket & enc_part2, it belongs
to the caller */
ticket_reply = *(header_ticket);
enc_tkt_reply = *(header_ticket->enc_part2);
old_life = enc_tkt_reply.times.endtime - enc_tkt_reply.times.starttime;
enc_tkt_reply.times.starttime = kdc_time;
enc_tkt_reply.times.endtime =
min(header_ticket->enc_part2->times.renew_till,
kdc_time + old_life);
} else {
/* not a renew request */
enc_tkt_reply.times.starttime = kdc_time;
until = (request->till == 0) ? kdc_infinity : request->till;
enc_tkt_reply.times.endtime =
min(until, min(enc_tkt_reply.times.starttime + server.max_life,
min(enc_tkt_reply.times.starttime + max_life_for_realm,
header_enc_tkt->times.endtime)));
if (isflagset(request->kdc_options, KDC_OPT_RENEWABLE_OK) &&
(enc_tkt_reply.times.endtime < request->till) &&
isflagset(header_enc_tkt->flags, TKT_FLG_RENEWABLE)) {
setflag(request->kdc_options, KDC_OPT_RENEWABLE);
request->rtime =
min(request->till, header_enc_tkt->times.renew_till);
}
}
rtime = (request->rtime == 0) ? kdc_infinity : request->rtime;
if (isflagset(request->kdc_options, KDC_OPT_RENEWABLE)) {
/* already checked above in policy check to reject request for a
renewable ticket using a non-renewable ticket */
setflag(enc_tkt_reply.flags, TKT_FLG_RENEWABLE);
enc_tkt_reply.times.renew_till =
min(rtime,
min(header_enc_tkt->times.renew_till,
enc_tkt_reply.times.starttime +
min(server.max_renewable_life,
max_renewable_life_for_realm)));
} else {
enc_tkt_reply.times.renew_till = 0;
}
/*
* Set authtime to be the same as header_ticket's
*/
enc_tkt_reply.times.authtime = header_enc_tkt->times.authtime;
/*
* Propagate the preauthentication flags through to the returned ticket.
*/
if (isflagset(header_enc_tkt->flags, TKT_FLG_PRE_AUTH))
setflag(enc_tkt_reply.flags, TKT_FLG_PRE_AUTH);
if (isflagset(header_enc_tkt->flags, TKT_FLG_HW_AUTH))
setflag(enc_tkt_reply.flags, TKT_FLG_HW_AUTH);
/* starttime is optional, and treated as authtime if not present.
so we can nuke it if it matches */
if (enc_tkt_reply.times.starttime == enc_tkt_reply.times.authtime)
enc_tkt_reply.times.starttime = 0;
if (isflagset(c_flags, KRB5_KDB_FLAG_PROTOCOL_TRANSITION)) {
errcode = krb5_unparse_name(kdc_context, s4u_x509_user->user_id.user, &s4u_name);
} else if (isflagset(c_flags, KRB5_KDB_FLAG_CONSTRAINED_DELEGATION)) {
errcode = krb5_unparse_name(kdc_context, header_enc_tkt->client, &s4u_name);
} else {
errcode = 0;
}
if (errcode) {
status = "UNPARSING S4U CLIENT";
goto cleanup;
}
if (isflagset(request->kdc_options, KDC_OPT_ENC_TKT_IN_SKEY)) {
krb5_enc_tkt_part *t2enc = request->second_ticket[st_idx]->enc_part2;
encrypting_key = *(t2enc->session);
} else {
/*
* Find the server key
*/
if ((errcode = krb5_dbe_find_enctype(kdc_context, &server,
-1, /* ignore keytype */
-1, /* Ignore salttype */
0,/* Get highest kvno */
&server_key))) {
status = "FINDING_SERVER_KEY";
goto cleanup;
}
if ((errcode = 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;
if ((errcode = krb5_dbe_find_mkey(kdc_context, master_keylist,
&server, &mkey_ptr))) {
status = "FINDING_MASTER_KEY";
goto cleanup;
}
} else {
status = "FINDING_MASTER_KEY";
goto cleanup;
}
}
/* convert server.key into a real key (it may be encrypted
* in the database) */
if ((errcode = krb5_dbekd_decrypt_key_data(kdc_context,
mkey_ptr,
server_key, &encrypting_key,
NULL))) {
status = "DECRYPT_SERVER_KEY";
goto cleanup;
}
}
if (isflagset(c_flags, KRB5_KDB_FLAG_CONSTRAINED_DELEGATION)) {
/*
* Don't allow authorization data to be disabled if constrained
* delegation is requested. We don't want to deny the server
* the ability to validate that delegation was used.
*/
clear(server.attributes, KRB5_KDB_NO_AUTH_DATA_REQUIRED);
}
if (isflagset(server.attributes, KRB5_KDB_NO_AUTH_DATA_REQUIRED) == 0) {
/*
* If we are not doing protocol transition/constrained delegation
* and there was no authorization data included, try to lookup
* the client principal as it may be mapped to a local account.
*
* Always validate authorization data for constrained delegation
* because we must validate the KDC signatures.
*/
if (!isflagset(c_flags, KRB5_KDB_FLAGS_S4U) &&
header_enc_tkt->authorization_data == NULL) {
/* Generate authorization data so we can include it in ticket */
setflag(c_flags, KRB5_KDB_FLAG_INCLUDE_PAC);
/* Map principals from foreign (possibly non-AD) realms */
setflag(c_flags, KRB5_KDB_FLAG_MAP_PRINCIPALS);
assert(c_nprincs == 0); /* should not have been looked up already */
c_nprincs = 1;
errcode = krb5_db_get_principal_ext(kdc_context,
header_enc_tkt->client,
c_flags,
&client,
&c_nprincs,
&more);
/*
* We can ignore errors because the principal may be a
* valid cross-realm principal for which we have no local
* mapping. But we do want to check that at most one entry
* was returned.
*/
if (errcode == 0 && (more || c_nprincs > 1)) {
errcode = KRB5KDC_ERR_PRINCIPAL_NOT_UNIQUE;
goto cleanup;
} else if (errcode) {
c_nprincs = 0;
}
}
}
enc_tkt_reply.authorization_data = NULL;
if (isflagset(c_flags, KRB5_KDB_FLAG_PROTOCOL_TRANSITION) &&
!isflagset(c_flags, KRB5_KDB_FLAG_CROSS_REALM))
enc_tkt_reply.client = s4u_x509_user->user_id.user;
else
enc_tkt_reply.client = header_enc_tkt->client;
enc_tkt_reply.session = &session_key;
enc_tkt_reply.transited.tr_type = KRB5_DOMAIN_X500_COMPRESS;
enc_tkt_reply.transited.tr_contents = empty_string; /* equivalent of "" */
errcode = handle_authdata(kdc_context,
c_flags,
(c_nprincs != 0) ? &client : NULL,
&server,
(k_nprincs != 0) ? &krbtgt : NULL,
subkey != NULL ? subkey :
header_ticket->enc_part2->session,
&encrypting_key, /* U2U or server key */
pkt,
request,
s4u_x509_user ?
s4u_x509_user->user_id.user : NULL,
header_enc_tkt,
&enc_tkt_reply);
if (errcode) {
krb5_klog_syslog(LOG_INFO, "TGS_REQ : handle_authdata (%d)", errcode);
status = "HANDLE_AUTHDATA";
goto cleanup;
}
if (is_referral && isflagset(s_flags, KRB5_KDB_FLAG_CANONICALIZE)) {
errcode = return_svr_referral_data(kdc_context,
&server, &reply_encpart);
if (errcode) {
status = "KDC_RETURN_ENC_PADATA";
goto cleanup;
}
}
/*
* Only add the realm of the presented tgt to the transited list if
* it is different than the local realm (cross-realm) and it is different
* than the realm of the client (since the realm of the client is already
* implicitly part of the transited list and should not be explicitly
* listed).
*/
/* realm compare is like strcmp, but knows how to deal with these args */
if (realm_compare(header_ticket->server, tgs_server) ||
realm_compare(header_ticket->server, enc_tkt_reply.client)) {
/* tgt issued by local realm or issued by realm of client */
enc_tkt_reply.transited = header_enc_tkt->transited;
} else {
/* tgt issued by some other realm and not the realm of the client */
/* assemble new transited field into allocated storage */
if (header_enc_tkt->transited.tr_type !=
KRB5_DOMAIN_X500_COMPRESS) {
status = "BAD_TRTYPE";
errcode = KRB5KDC_ERR_TRTYPE_NOSUPP;
goto cleanup;
}
enc_tkt_transited.tr_type = KRB5_DOMAIN_X500_COMPRESS;
enc_tkt_transited.magic = 0;
enc_tkt_transited.tr_contents.magic = 0;
enc_tkt_transited.tr_contents.data = 0;
enc_tkt_transited.tr_contents.length = 0;
enc_tkt_reply.transited = enc_tkt_transited;
if ((errcode =
add_to_transited(&header_enc_tkt->transited.tr_contents,
&enc_tkt_reply.transited.tr_contents,
header_ticket->server,
enc_tkt_reply.client,
request->server))) {
status = "ADD_TR_FAIL";
goto cleanup;
}
newtransited = 1;
}
if (isflagset(c_flags, KRB5_KDB_FLAG_CROSS_REALM)) {
errcode = validate_transit_path(kdc_context, header_enc_tkt->client,
&server,
(k_nprincs != 0) ? &krbtgt : NULL);
if (errcode) {
status = "NON_TRANSITIVE";
goto cleanup;
}
}
if (!isflagset (request->kdc_options, KDC_OPT_DISABLE_TRANSITED_CHECK)) {
unsigned int tlen;
char *tdots;
errcode = kdc_check_transited_list (kdc_context,
&enc_tkt_reply.transited.tr_contents,
krb5_princ_realm (kdc_context, header_enc_tkt->client),
krb5_princ_realm (kdc_context, request->server));
tlen = enc_tkt_reply.transited.tr_contents.length;
tdots = tlen > 125 ? "..." : "";
tlen = tlen > 125 ? 125 : tlen;
if (errcode == 0) {
setflag (enc_tkt_reply.flags, TKT_FLG_TRANSIT_POLICY_CHECKED);
} else if (errcode == KRB5KRB_AP_ERR_ILL_CR_TKT)
krb5_klog_syslog (LOG_INFO,
"bad realm transit path from '%s' to '%s' "
"via '%.*s%s'",
cname ? cname : "<unknown client>",
sname ? sname : "<unknown server>",
tlen,
enc_tkt_reply.transited.tr_contents.data,
tdots);
else {
emsg = krb5_get_error_message(kdc_context, errcode);
krb5_klog_syslog (LOG_ERR,
"unexpected error checking transit from "
"'%s' to '%s' via '%.*s%s': %s",
cname ? cname : "<unknown client>",
sname ? sname : "<unknown server>",
tlen,
enc_tkt_reply.transited.tr_contents.data,
tdots, emsg);
krb5_free_error_message(kdc_context, emsg);
emsg = NULL;
}
} else
krb5_klog_syslog (LOG_INFO, "not checking transit path");
if (reject_bad_transit
&& !isflagset (enc_tkt_reply.flags, TKT_FLG_TRANSIT_POLICY_CHECKED)) {
errcode = KRB5KDC_ERR_POLICY;
status = "BAD_TRANSIT";
goto cleanup;
}
ticket_reply.enc_part2 = &enc_tkt_reply;
/*
* If we are doing user-to-user authentication, then make sure
* that the client for the second ticket matches the request
* server, and then encrypt the ticket using the session key of
* the second ticket.
*/
if (isflagset(request->kdc_options, KDC_OPT_ENC_TKT_IN_SKEY)) {
/*
* Make sure the client for the second ticket matches
* requested server.
*/
krb5_enc_tkt_part *t2enc = request->second_ticket[st_idx]->enc_part2;
krb5_principal client2 = t2enc->client;
if (!krb5_principal_compare(kdc_context, request->server, client2)) {
if ((errcode = krb5_unparse_name(kdc_context, client2, &altcname)))
altcname = 0;
if (altcname != NULL)
limit_string(altcname);
errcode = KRB5KDC_ERR_SERVER_NOMATCH;
status = "2ND_TKT_MISMATCH";
goto cleanup;
}
ticket_kvno = 0;
ticket_reply.enc_part.enctype = t2enc->session->enctype;
st_idx++;
} else {
ticket_kvno = server_key->key_data_kvno;
}
errcode = krb5_encrypt_tkt_part(kdc_context, &encrypting_key,
&ticket_reply);
if (!isflagset(request->kdc_options, KDC_OPT_ENC_TKT_IN_SKEY))
krb5_free_keyblock_contents(kdc_context, &encrypting_key);
if (errcode) {
status = "TKT_ENCRYPT";
goto cleanup;
}
ticket_reply.enc_part.kvno = ticket_kvno;
/* Start assembling the response */
reply.msg_type = KRB5_TGS_REP;
reply.padata = 0;/* always */
if (isflagset(c_flags, KRB5_KDB_FLAG_PROTOCOL_TRANSITION) &&
find_pa_data(request->padata, KRB5_PADATA_S4U_X509_USER) != NULL) {
errcode = kdc_make_s4u2self_rep(kdc_context,
subkey,
header_ticket->enc_part2->session,
s4u_x509_user,
&reply,
&reply_encpart);
if (errcode) {
status = "KDC_RETURN_S4U2SELF_PADATA";
goto cleanup;
}
}
reply.client = enc_tkt_reply.client;
reply.enc_part.kvno = 0;/* We are using the session key */
reply.ticket = &ticket_reply;
reply_encpart.session = &session_key;
reply_encpart.nonce = request->nonce;
/* copy the time fields EXCEPT for authtime; its location
is used for ktime */
reply_encpart.times = enc_tkt_reply.times;
reply_encpart.times.authtime = header_enc_tkt->times.authtime;
/* starttime is optional, and treated as authtime if not present.
so we can nuke it if it matches */
if (enc_tkt_reply.times.starttime == enc_tkt_reply.times.authtime)
enc_tkt_reply.times.starttime = 0;
nolrentry.lr_type = KRB5_LRQ_NONE;
nolrentry.value = 0;
nolrarray[0] = &nolrentry;
nolrarray[1] = 0;
reply_encpart.last_req = nolrarray; /* not available for TGS reqs */
reply_encpart.key_exp = 0;/* ditto */
reply_encpart.flags = enc_tkt_reply.flags;
reply_encpart.server = ticket_reply.server;
/* use the session key in the ticket, unless there's a subsession key
in the AP_REQ */
reply.enc_part.enctype = subkey ? subkey->enctype :
header_ticket->enc_part2->session->enctype;
errcode = kdc_fast_response_handle_padata(state, request, &reply,
subkey?subkey->enctype:header_ticket->enc_part2->session->enctype);
if (errcode !=0 ) {
status = "Preparing FAST padata";
goto cleanup;
}
errcode =kdc_fast_handle_reply_key(state, subkey?subkey:header_ticket->enc_part2->session, &reply_key);
if (errcode) {
status = "generating reply key";
goto cleanup;
}
errcode = krb5_encode_kdc_rep(kdc_context, KRB5_TGS_REP, &reply_encpart,
subkey ? 1 : 0,
reply_key,
&reply, response);
if (errcode) {
status = "ENCODE_KDC_REP";
} else {
status = "ISSUE";
}
memset(ticket_reply.enc_part.ciphertext.data, 0,
ticket_reply.enc_part.ciphertext.length);
free(ticket_reply.enc_part.ciphertext.data);
/* these parts are left on as a courtesy from krb5_encode_kdc_rep so we
can use them in raw form if needed. But, we don't... */
memset(reply.enc_part.ciphertext.data, 0,
reply.enc_part.ciphertext.length);
free(reply.enc_part.ciphertext.data);
cleanup:
assert(status != NULL);
if (reply_key)
krb5_free_keyblock(kdc_context, reply_key);
if (errcode)
emsg = krb5_get_error_message (kdc_context, errcode);
log_tgs_req(from, request, &reply, cname, sname, altcname, authtime,
c_flags, s4u_name, status, errcode, emsg);
if (errcode) {
krb5_free_error_message (kdc_context, emsg);
emsg = NULL;
}
if (errcode) {
int got_err = 0;
if (status == 0) {
status = krb5_get_error_message (kdc_context, errcode);
got_err = 1;
}
errcode -= ERROR_TABLE_BASE_krb5;
if (errcode < 0 || errcode > 128)
errcode = KRB_ERR_GENERIC;
retval = prepare_error_tgs(state, request, header_ticket, errcode,
nprincs ? server.princ : NULL,
response, status);
if (got_err) {
krb5_free_error_message (kdc_context, status);
status = 0;
}
}
if (header_ticket != NULL)
krb5_free_ticket(kdc_context, header_ticket);
if (request != NULL)
krb5_free_kdc_req(kdc_context, request);
if (state)
kdc_free_rstate(state);
if (cname != NULL)
free(cname);
if (sname != NULL)
free(sname);
if (nprincs != 0)
krb5_db_free_principal(kdc_context, &server, 1);
if (session_key.contents != NULL)
krb5_free_keyblock_contents(kdc_context, &session_key);
if (newtransited)
free(enc_tkt_reply.transited.tr_contents.data);
if (k_nprincs)
krb5_db_free_principal(kdc_context, &krbtgt, k_nprincs);
if (c_nprincs)
krb5_db_free_principal(kdc_context, &client, c_nprincs);
if (s4u_x509_user != NULL)
krb5_free_pa_s4u_x509_user(kdc_context, s4u_x509_user);
if (kdc_issued_auth_data != NULL)
krb5_free_authdata(kdc_context, kdc_issued_auth_data);
if (s4u_name != NULL)
free(s4u_name);
if (subkey != NULL)
krb5_free_keyblock(kdc_context, subkey);
if (reply.padata)
krb5_free_pa_data(kdc_context, reply.padata);
if (reply_encpart.enc_padata)
krb5_free_pa_data(kdc_context, reply_encpart.enc_padata);
return retval;
}
static krb5_error_code
rd_req_decoded_opt(krb5_context context, krb5_auth_context *auth_context,
const krb5_ap_req *req, krb5_const_principal server,
krb5_keytab keytab, krb5_flags *ap_req_options,
krb5_ticket **ticket, int check_valid_flag)
{
krb5_error_code retval = 0;
krb5_enctype *desired_etypes = NULL;
int desired_etypes_len = 0;
int rfc4537_etypes_len = 0;
krb5_enctype *permitted_etypes = NULL;
int permitted_etypes_len = 0;
krb5_keyblock decrypt_key;
decrypt_key.enctype = ENCTYPE_NULL;
decrypt_key.contents = NULL;
req->ticket->enc_part2 = NULL;
/* if (req->ap_options & AP_OPTS_USE_SESSION_KEY)
do we need special processing here ? */
/* decrypt the ticket */
if ((*auth_context)->key) { /* User to User authentication */
if ((retval = krb5_decrypt_tkt_part(context,
&(*auth_context)->key->keyblock,
req->ticket)))
goto cleanup;
if (check_valid_flag) {
decrypt_key = (*auth_context)->key->keyblock;
(*auth_context)->key->keyblock.contents = NULL;
}
krb5_k_free_key(context, (*auth_context)->key);
(*auth_context)->key = NULL;
} else {
retval = decrypt_ticket(context, req, server, keytab,
check_valid_flag ? &decrypt_key : NULL);
if (retval)
goto cleanup;
}
TRACE_RD_REQ_TICKET(context, req->ticket->enc_part2->client,
req->ticket->server, req->ticket->enc_part2->session);
/* XXX this is an evil hack. check_valid_flag is set iff the call
is not from inside the kdc. we can use this to determine which
key usage to use */
#ifndef LEAN_CLIENT
if ((retval = decrypt_authenticator(context, req,
&((*auth_context)->authentp),
check_valid_flag)))
goto cleanup;
#endif
if (!krb5_principal_compare(context, (*auth_context)->authentp->client,
req->ticket->enc_part2->client)) {
retval = KRB5KRB_AP_ERR_BADMATCH;
goto cleanup;
}
if ((*auth_context)->remote_addr &&
!krb5_address_search(context, (*auth_context)->remote_addr,
req->ticket->enc_part2->caddrs)) {
retval = KRB5KRB_AP_ERR_BADADDR;
goto cleanup;
}
if (!server) {
server = req->ticket->server;
}
/* Get an rcache if necessary. */
if (((*auth_context)->rcache == NULL)
&& ((*auth_context)->auth_context_flags & KRB5_AUTH_CONTEXT_DO_TIME)
&& server) {
if ((retval = krb5_get_server_rcache(context,
krb5_princ_component(context,server,0),
&(*auth_context)->rcache)))
goto cleanup;
}
/* okay, now check cross-realm policy */
#if defined(_SINGLE_HOP_ONLY)
/* Single hop cross-realm tickets only */
{
krb5_transited *trans = &(req->ticket->enc_part2->transited);
/* If the transited list is empty, then we have at most one hop */
if (trans->tr_contents.length > 0 && trans->tr_contents.data[0])
retval = KRB5KRB_AP_ERR_ILL_CR_TKT;
}
#elif defined(_NO_CROSS_REALM)
/* No cross-realm tickets */
{
char * lrealm;
krb5_data * realm;
krb5_transited * trans;
realm = krb5_princ_realm(context, req->ticket->enc_part2->client);
trans = &(req->ticket->enc_part2->transited);
/*
* If the transited list is empty, then we have at most one hop
* So we also have to check that the client's realm is the local one
*/
krb5_get_default_realm(context, &lrealm);
if ((trans->tr_contents.length > 0 && trans->tr_contents.data[0]) ||
!data_eq_string(*realm, lrealm)) {
retval = KRB5KRB_AP_ERR_ILL_CR_TKT;
}
free(lrealm);
}
#else
/* Hierarchical Cross-Realm */
{
krb5_data * realm;
krb5_transited * trans;
realm = krb5_princ_realm(context, req->ticket->enc_part2->client);
trans = &(req->ticket->enc_part2->transited);
/*
* If the transited list is not empty, then check that all realms
* transited are within the hierarchy between the client's realm
* and the local realm.
*/
if (trans->tr_contents.length > 0 && trans->tr_contents.data[0]) {
retval = krb5_check_transited_list(context, &(trans->tr_contents),
realm,
krb5_princ_realm (context,server));
}
}
#endif
if (retval) goto cleanup;
/* only check rcache if sender has provided one---some services
may not be able to use replay caches (such as datagram servers) */
if ((*auth_context)->rcache) {
krb5_donot_replay rep;
krb5_tkt_authent tktauthent;
tktauthent.ticket = req->ticket;
tktauthent.authenticator = (*auth_context)->authentp;
if (!(retval = krb5_auth_to_rep(context, &tktauthent, &rep))) {
retval = krb5_rc_hash_message(context,
&req->authenticator.ciphertext,
&rep.msghash);
if (!retval) {
retval = krb5_rc_store(context, (*auth_context)->rcache, &rep);
free(rep.msghash);
}
free(rep.server);
free(rep.client);
}
if (retval)
goto cleanup;
}
retval = krb5int_validate_times(context, &req->ticket->enc_part2->times);
if (retval != 0)
goto cleanup;
if ((retval = krb5_check_clockskew(context, (*auth_context)->authentp->ctime)))
goto cleanup;
if (check_valid_flag) {
if (req->ticket->enc_part2->flags & TKT_FLG_INVALID) {
retval = KRB5KRB_AP_ERR_TKT_INVALID;
goto cleanup;
}
if ((retval = krb5_authdata_context_init(context,
&(*auth_context)->ad_context)))
goto cleanup;
if ((retval = krb5int_authdata_verify(context,
(*auth_context)->ad_context,
AD_USAGE_MASK,
auth_context,
&decrypt_key,
req)))
goto cleanup;
}
/* read RFC 4537 etype list from sender */
retval = decode_etype_list(context,
(*auth_context)->authentp,
&desired_etypes,
&rfc4537_etypes_len);
if (retval != 0)
goto cleanup;
if (desired_etypes == NULL)
desired_etypes = (krb5_enctype *)calloc(4, sizeof(krb5_enctype));
else
desired_etypes = (krb5_enctype *)realloc(desired_etypes,
(rfc4537_etypes_len + 4) *
sizeof(krb5_enctype));
if (desired_etypes == NULL) {
retval = ENOMEM;
goto cleanup;
}
desired_etypes_len = rfc4537_etypes_len;
/*
* RFC 4537:
*
* If the EtypeList is present and the server prefers an enctype from
* the client's enctype list over that of the AP-REQ authenticator
* subkey (if that is present) or the service ticket session key, the
* server MUST create a subkey using that enctype. This negotiated
* subkey is sent in the subkey field of AP-REP message, and it is then
* used as the protocol key or base key [RFC3961] for subsequent
* communication.
*
* If the enctype of the ticket session key is included in the enctype
* list sent by the client, it SHOULD be the last on the list;
* otherwise, this enctype MUST NOT be negotiated if it was not included
* in the list.
*
* The second paragraph does appear to contradict the first with respect
* to whether it is legal to negotiate the ticket session key type if it
* is absent in the EtypeList. A literal reading suggests that we can use
* the AP-REQ subkey enctype. Also a client has no way of distinguishing
* a server that does not RFC 4537 from one that has chosen the same
* enctype as the ticket session key for the acceptor subkey, surely.
*/
if ((*auth_context)->authentp->subkey != NULL) {
desired_etypes[desired_etypes_len++] = (*auth_context)->authentp->subkey->enctype;
}
desired_etypes[desired_etypes_len++] = req->ticket->enc_part2->session->enctype;
desired_etypes[desired_etypes_len] = ENCTYPE_NULL;
if (((*auth_context)->auth_context_flags & KRB5_AUTH_CONTEXT_PERMIT_ALL) == 0) {
if ((*auth_context)->permitted_etypes != NULL) {
permitted_etypes = (*auth_context)->permitted_etypes;
} else {
retval = krb5_get_permitted_enctypes(context, &permitted_etypes);
if (retval != 0)
goto cleanup;
}
permitted_etypes_len = krb5int_count_etypes(permitted_etypes);
} else {
permitted_etypes = NULL;
permitted_etypes_len = 0;
}
/* check if the various etypes are permitted */
retval = negotiate_etype(context,
desired_etypes, desired_etypes_len,
rfc4537_etypes_len,
permitted_etypes, permitted_etypes_len,
&(*auth_context)->negotiated_etype);
if (retval != 0)
goto cleanup;
TRACE_RD_REQ_NEGOTIATED_ETYPE(context, (*auth_context)->negotiated_etype);
assert((*auth_context)->negotiated_etype != ENCTYPE_NULL);
(*auth_context)->remote_seq_number = (*auth_context)->authentp->seq_number;
if ((*auth_context)->authentp->subkey) {
TRACE_RD_REQ_SUBKEY(context, (*auth_context)->authentp->subkey);
if ((retval = krb5_k_create_key(context,
(*auth_context)->authentp->subkey,
&((*auth_context)->recv_subkey))))
goto cleanup;
retval = krb5_k_create_key(context, (*auth_context)->authentp->subkey,
&((*auth_context)->send_subkey));
if (retval) {
krb5_k_free_key(context, (*auth_context)->recv_subkey);
(*auth_context)->recv_subkey = NULL;
goto cleanup;
}
} else {
(*auth_context)->recv_subkey = 0;
(*auth_context)->send_subkey = 0;
}
if ((retval = krb5_k_create_key(context, req->ticket->enc_part2->session,
&((*auth_context)->key))))
goto cleanup;
debug_log_authz_data("ticket", req->ticket->enc_part2->authorization_data);
/*
* If not AP_OPTS_MUTUAL_REQUIRED then and sequence numbers are used
* then the default sequence number is the one's complement of the
* sequence number sent ot us.
*/
if ((!(req->ap_options & AP_OPTS_MUTUAL_REQUIRED)) &&
(*auth_context)->remote_seq_number) {
(*auth_context)->local_seq_number ^=
(*auth_context)->remote_seq_number;
}
if (ticket)
if ((retval = krb5_copy_ticket(context, req->ticket, ticket)))
goto cleanup;
if (ap_req_options) {
*ap_req_options = req->ap_options & AP_OPTS_WIRE_MASK;
if (rfc4537_etypes_len != 0)
*ap_req_options |= AP_OPTS_ETYPE_NEGOTIATION;
if ((*auth_context)->negotiated_etype !=
krb5_k_key_enctype(context, (*auth_context)->key))
*ap_req_options |= AP_OPTS_USE_SUBKEY;
}
retval = 0;
cleanup:
if (desired_etypes != NULL)
free(desired_etypes);
if (permitted_etypes != NULL &&
permitted_etypes != (*auth_context)->permitted_etypes)
free(permitted_etypes);
if (retval) {
/* only free if we're erroring out...otherwise some
applications will need the output. */
if (req->ticket->enc_part2)
krb5_free_enc_tkt_part(context, req->ticket->enc_part2);
req->ticket->enc_part2 = NULL;
}
if (check_valid_flag)
krb5_free_keyblock_contents(context, &decrypt_key);
return retval;
}
/*ARGSUSED*/
krb5_error_code
process_tgs_req(krb5_data *pkt, const krb5_fulladdr *from,
krb5_data **response)
{
krb5_keyblock * subkey = 0;
krb5_kdc_req *request = 0;
krb5_db_entry server;
krb5_kdc_rep reply;
krb5_enc_kdc_rep_part reply_encpart;
krb5_ticket ticket_reply, *header_ticket = 0;
int st_idx = 0;
krb5_enc_tkt_part enc_tkt_reply;
krb5_transited enc_tkt_transited;
int newtransited = 0;
krb5_error_code retval = 0;
int nprincs = 0;
krb5_boolean more;
krb5_timestamp kdc_time, authtime=0;
krb5_keyblock session_key;
krb5_timestamp until, rtime;
krb5_keyblock encrypting_key;
krb5_key_data *server_key;
char *cname = 0, *sname = 0, *tmp = 0;
const char *fromstring = 0;
krb5_last_req_entry *nolrarray[2], nolrentry;
/* krb5_address *noaddrarray[1]; */
krb5_enctype useenctype;
int errcode, errcode2;
register int i;
int firstpass = 1;
const char *status = 0;
char ktypestr[128];
char rep_etypestr[128];
char fromstringbuf[70];
session_key.contents = 0;
retval = decode_krb5_tgs_req(pkt, &request);
if (retval)
return retval;
if (request->msg_type != KRB5_TGS_REQ)
return KRB5_BADMSGTYPE;
ktypes2str(ktypestr, sizeof(ktypestr),
request->nktypes, request->ktype);
/*
* setup_server_realm() sets up the global realm-specific data pointer.
*/
if ((retval = setup_server_realm(request->server))) {
krb5_free_kdc_req(kdc_context, request);
return retval;
}
fromstring = inet_ntop(ADDRTYPE2FAMILY(from->address->addrtype),
from->address->contents,
fromstringbuf, sizeof(fromstringbuf));
if (!fromstring)
fromstring = "<unknown>";
if ((errcode = krb5_unparse_name(kdc_context, request->server, &sname))) {
status = "UNPARSING SERVER";
goto cleanup;
}
limit_string(sname);
/* errcode = kdc_process_tgs_req(request, from, pkt, &req_authdat); */
errcode = kdc_process_tgs_req(request, from, pkt, &header_ticket, &subkey);
if (header_ticket && header_ticket->enc_part2 &&
(errcode2 = krb5_unparse_name(kdc_context,
header_ticket->enc_part2->client,
&cname))) {
status = "UNPARSING CLIENT";
errcode = errcode2;
goto cleanup;
}
limit_string(cname);
if (errcode) {
status = "PROCESS_TGS";
goto cleanup;
}
if (!header_ticket) {
errcode = KRB5_NO_TKT_SUPPLIED; /* XXX? */
status="UNEXPECTED NULL in header_ticket";
goto cleanup;
}
/*
* We've already dealt with the AP_REQ authentication, so we can
* use header_ticket freely. The encrypted part (if any) has been
* decrypted with the session key.
*/
authtime = header_ticket->enc_part2->times.authtime;
/* XXX make sure server here has the proper realm...taken from AP_REQ
header? */
nprincs = 1;
if ((errcode = get_principal(kdc_context, request->server, &server,
&nprincs, &more))) {
status = "LOOKING_UP_SERVER";
nprincs = 0;
goto cleanup;
}
tgt_again:
if (more) {
status = "NON_UNIQUE_PRINCIPAL";
errcode = KRB5KDC_ERR_PRINCIPAL_NOT_UNIQUE;
goto cleanup;
} else if (nprincs != 1) {
/*
* might be a request for a TGT for some other realm; we
* should do our best to find such a TGS in this db
*/
if (firstpass && krb5_is_tgs_principal(request->server) == TRUE) {
if (krb5_princ_size(kdc_context, request->server) == 2) {
krb5_data *server_1 =
krb5_princ_component(kdc_context, request->server, 1);
krb5_data *tgs_1 =
krb5_princ_component(kdc_context, tgs_server, 1);
if (!tgs_1 || !data_eq(*server_1, *tgs_1)) {
krb5_db_free_principal(kdc_context, &server, nprincs);
find_alternate_tgs(request, &server, &more, &nprincs);
firstpass = 0;
goto tgt_again;
}
}
}
krb5_db_free_principal(kdc_context, &server, nprincs);
status = "UNKNOWN_SERVER";
errcode = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN;
goto cleanup;
}
if ((errcode = krb5_timeofday(kdc_context, &kdc_time))) {
status = "TIME_OF_DAY";
goto cleanup;
}
if ((retval = validate_tgs_request(request, server, header_ticket,
kdc_time, &status))) {
if (!status)
status = "UNKNOWN_REASON";
errcode = retval + ERROR_TABLE_BASE_krb5;
goto cleanup;
}
/*
* We pick the session keytype here....
*
* Some special care needs to be taken in the user-to-user
* case, since we don't know what keytypes the application server
* which is doing user-to-user authentication can support. We
* know that it at least must be able to support the encryption
* type of the session key in the TGT, since otherwise it won't be
* able to decrypt the U2U ticket! So we use that in preference
* to anything else.
*/
useenctype = 0;
if (isflagset(request->kdc_options, KDC_OPT_ENC_TKT_IN_SKEY)) {
krb5_keyblock * st_sealing_key;
krb5_kvno st_srv_kvno;
krb5_enctype etype;
/*
* Get the key for the second ticket, and decrypt it.
*/
if ((errcode = kdc_get_server_key(request->second_ticket[st_idx],
&st_sealing_key,
&st_srv_kvno))) {
status = "2ND_TKT_SERVER";
goto cleanup;
}
errcode = krb5_decrypt_tkt_part(kdc_context, st_sealing_key,
request->second_ticket[st_idx]);
krb5_free_keyblock(kdc_context, st_sealing_key);
if (errcode) {
status = "2ND_TKT_DECRYPT";
goto cleanup;
}
etype = request->second_ticket[st_idx]->enc_part2->session->enctype;
if (!krb5_c_valid_enctype(etype)) {
status = "BAD_ETYPE_IN_2ND_TKT";
errcode = KRB5KDC_ERR_ETYPE_NOSUPP;
goto cleanup;
}
for (i = 0; i < request->nktypes; i++) {
if (request->ktype[i] == etype) {
useenctype = etype;
break;
}
}
}
/*
* Select the keytype for the ticket session key.
*/
if ((useenctype == 0) &&
(useenctype = select_session_keytype(kdc_context, &server,
request->nktypes,
request->ktype)) == 0) {
/* unsupported ktype */
status = "BAD_ENCRYPTION_TYPE";
errcode = KRB5KDC_ERR_ETYPE_NOSUPP;
goto cleanup;
}
errcode = krb5_c_make_random_key(kdc_context, useenctype, &session_key);
if (errcode) {
/* random key failed */
status = "RANDOM_KEY_FAILED";
goto cleanup;
}
ticket_reply.server = request->server; /* XXX careful for realm... */
enc_tkt_reply.flags = 0;
enc_tkt_reply.times.starttime = 0;
/*
* Fix header_ticket's starttime; if it's zero, fill in the
* authtime's value.
*/
if (!(header_ticket->enc_part2->times.starttime))
header_ticket->enc_part2->times.starttime =
header_ticket->enc_part2->times.authtime;
/* don't use new addresses unless forwarded, see below */
enc_tkt_reply.caddrs = header_ticket->enc_part2->caddrs;
/* noaddrarray[0] = 0; */
reply_encpart.caddrs = 0; /* optional...don't put it in */
/* It should be noted that local policy may affect the */
/* processing of any of these flags. For example, some */
/* realms may refuse to issue renewable tickets */
if (isflagset(request->kdc_options, KDC_OPT_FORWARDABLE))
setflag(enc_tkt_reply.flags, TKT_FLG_FORWARDABLE);
if (isflagset(request->kdc_options, KDC_OPT_FORWARDED)) {
setflag(enc_tkt_reply.flags, TKT_FLG_FORWARDED);
/* include new addresses in ticket & reply */
enc_tkt_reply.caddrs = request->addresses;
reply_encpart.caddrs = request->addresses;
}
if (isflagset(header_ticket->enc_part2->flags, TKT_FLG_FORWARDED))
setflag(enc_tkt_reply.flags, TKT_FLG_FORWARDED);
if (isflagset(request->kdc_options, KDC_OPT_PROXIABLE))
setflag(enc_tkt_reply.flags, TKT_FLG_PROXIABLE);
if (isflagset(request->kdc_options, KDC_OPT_PROXY)) {
setflag(enc_tkt_reply.flags, TKT_FLG_PROXY);
/* include new addresses in ticket & reply */
enc_tkt_reply.caddrs = request->addresses;
reply_encpart.caddrs = request->addresses;
}
if (isflagset(request->kdc_options, KDC_OPT_ALLOW_POSTDATE))
setflag(enc_tkt_reply.flags, TKT_FLG_MAY_POSTDATE);
if (isflagset(request->kdc_options, KDC_OPT_POSTDATED)) {
setflag(enc_tkt_reply.flags, TKT_FLG_POSTDATED);
setflag(enc_tkt_reply.flags, TKT_FLG_INVALID);
enc_tkt_reply.times.starttime = request->from;
} else
enc_tkt_reply.times.starttime = kdc_time;
if (isflagset(request->kdc_options, KDC_OPT_VALIDATE)) {
/* BEWARE of allocation hanging off of ticket & enc_part2, it belongs
to the caller */
ticket_reply = *(header_ticket);
enc_tkt_reply = *(header_ticket->enc_part2);
enc_tkt_reply.authorization_data = NULL;
clear(enc_tkt_reply.flags, TKT_FLG_INVALID);
}
if (isflagset(request->kdc_options, KDC_OPT_RENEW)) {
krb5_deltat old_life;
/* BEWARE of allocation hanging off of ticket & enc_part2, it belongs
to the caller */
ticket_reply = *(header_ticket);
enc_tkt_reply = *(header_ticket->enc_part2);
enc_tkt_reply.authorization_data = NULL;
old_life = enc_tkt_reply.times.endtime - enc_tkt_reply.times.starttime;
enc_tkt_reply.times.starttime = kdc_time;
enc_tkt_reply.times.endtime =
min(header_ticket->enc_part2->times.renew_till,
kdc_time + old_life);
} else {
/* not a renew request */
enc_tkt_reply.times.starttime = kdc_time;
until = (request->till == 0) ? kdc_infinity : request->till;
enc_tkt_reply.times.endtime =
min(until, min(enc_tkt_reply.times.starttime + server.max_life,
min(enc_tkt_reply.times.starttime + max_life_for_realm,
header_ticket->enc_part2->times.endtime)));
if (isflagset(request->kdc_options, KDC_OPT_RENEWABLE_OK) &&
(enc_tkt_reply.times.endtime < request->till) &&
isflagset(header_ticket->enc_part2->flags,
TKT_FLG_RENEWABLE)) {
setflag(request->kdc_options, KDC_OPT_RENEWABLE);
request->rtime =
min(request->till,
header_ticket->enc_part2->times.renew_till);
}
}
rtime = (request->rtime == 0) ? kdc_infinity : request->rtime;
if (isflagset(request->kdc_options, KDC_OPT_RENEWABLE)) {
/* already checked above in policy check to reject request for a
renewable ticket using a non-renewable ticket */
setflag(enc_tkt_reply.flags, TKT_FLG_RENEWABLE);
enc_tkt_reply.times.renew_till =
min(rtime,
min(header_ticket->enc_part2->times.renew_till,
enc_tkt_reply.times.starttime +
min(server.max_renewable_life,
max_renewable_life_for_realm)));
} else {
enc_tkt_reply.times.renew_till = 0;
}
/*
* Set authtime to be the same as header_ticket's
*/
enc_tkt_reply.times.authtime = header_ticket->enc_part2->times.authtime;
/*
* Propagate the preauthentication flags through to the returned ticket.
*/
if (isflagset(header_ticket->enc_part2->flags, TKT_FLG_PRE_AUTH))
setflag(enc_tkt_reply.flags, TKT_FLG_PRE_AUTH);
if (isflagset(header_ticket->enc_part2->flags, TKT_FLG_HW_AUTH))
setflag(enc_tkt_reply.flags, TKT_FLG_HW_AUTH);
/* starttime is optional, and treated as authtime if not present.
so we can nuke it if it matches */
if (enc_tkt_reply.times.starttime == enc_tkt_reply.times.authtime)
enc_tkt_reply.times.starttime = 0;
/* assemble any authorization data */
if (request->authorization_data.ciphertext.data) {
krb5_data scratch;
scratch.length = request->authorization_data.ciphertext.length;
if (!(scratch.data =
malloc(request->authorization_data.ciphertext.length))) {
status = "AUTH_NOMEM";
errcode = ENOMEM;
goto cleanup;
}
if ((errcode = krb5_c_decrypt(kdc_context,
header_ticket->enc_part2->session,
KRB5_KEYUSAGE_TGS_REQ_AD_SESSKEY,
0, &request->authorization_data,
&scratch))) {
status = "AUTH_ENCRYPT_FAIL";
free(scratch.data);
goto cleanup;
}
/* scratch now has the authorization data, so we decode it */
errcode = decode_krb5_authdata(&scratch, &(request->unenc_authdata));
free(scratch.data);
if (errcode) {
status = "AUTH_DECODE";
goto cleanup;
}
if ((errcode =
concat_authorization_data(request->unenc_authdata,
header_ticket->enc_part2->authorization_data,
&enc_tkt_reply.authorization_data))) {
status = "CONCAT_AUTH";
goto cleanup;
}
} else
enc_tkt_reply.authorization_data =
header_ticket->enc_part2->authorization_data;
enc_tkt_reply.session = &session_key;
enc_tkt_reply.client = header_ticket->enc_part2->client;
enc_tkt_reply.transited.tr_type = KRB5_DOMAIN_X500_COMPRESS;
enc_tkt_reply.transited.tr_contents = empty_string; /* equivalent of "" */
/*
* Only add the realm of the presented tgt to the transited list if
* it is different than the local realm (cross-realm) and it is different
* than the realm of the client (since the realm of the client is already
* implicitly part of the transited list and should not be explicitly
* listed).
*/
/* realm compare is like strcmp, but knows how to deal with these args */
if (realm_compare(header_ticket->server, tgs_server) ||
realm_compare(header_ticket->server, enc_tkt_reply.client)) {
/* tgt issued by local realm or issued by realm of client */
enc_tkt_reply.transited = header_ticket->enc_part2->transited;
} else {
/* tgt issued by some other realm and not the realm of the client */
/* assemble new transited field into allocated storage */
if (header_ticket->enc_part2->transited.tr_type !=
KRB5_DOMAIN_X500_COMPRESS) {
status = "BAD_TRTYPE";
errcode = KRB5KDC_ERR_TRTYPE_NOSUPP;
goto cleanup;
}
enc_tkt_transited.tr_type = KRB5_DOMAIN_X500_COMPRESS;
enc_tkt_transited.magic = 0;
enc_tkt_transited.tr_contents.magic = 0;
enc_tkt_transited.tr_contents.data = 0;
enc_tkt_transited.tr_contents.length = 0;
enc_tkt_reply.transited = enc_tkt_transited;
if ((errcode =
add_to_transited(&header_ticket->enc_part2->transited.tr_contents,
&enc_tkt_reply.transited.tr_contents,
header_ticket->server,
enc_tkt_reply.client,
request->server))) {
status = "ADD_TR_FAIL";
goto cleanup;
}
newtransited = 1;
}
if (!isflagset (request->kdc_options, KDC_OPT_DISABLE_TRANSITED_CHECK)) {
unsigned int tlen;
char *tdots;
errcode = krb5_check_transited_list (kdc_context,
&enc_tkt_reply.transited.tr_contents,
krb5_princ_realm (kdc_context, header_ticket->enc_part2->client),
krb5_princ_realm (kdc_context, request->server));
tlen = enc_tkt_reply.transited.tr_contents.length;
tdots = tlen > 125 ? "..." : "";
tlen = tlen > 125 ? 125 : tlen;
if (errcode == 0) {
setflag (enc_tkt_reply.flags, TKT_FLG_TRANSIT_POLICY_CHECKED);
} else if (errcode == KRB5KRB_AP_ERR_ILL_CR_TKT)
krb5_klog_syslog (LOG_INFO,
"bad realm transit path from '%s' to '%s' "
"via '%.*s%s'",
cname ? cname : "<unknown client>",
sname ? sname : "<unknown server>",
tlen,
enc_tkt_reply.transited.tr_contents.data,
tdots);
else {
const char *emsg = krb5_get_error_message(kdc_context, errcode);
krb5_klog_syslog (LOG_ERR,
"unexpected error checking transit from "
"'%s' to '%s' via '%.*s%s': %s",
cname ? cname : "<unknown client>",
sname ? sname : "<unknown server>",
tlen,
enc_tkt_reply.transited.tr_contents.data,
tdots, emsg);
krb5_free_error_message(kdc_context, emsg);
}
} else
krb5_klog_syslog (LOG_INFO, "not checking transit path");
if (reject_bad_transit
&& !isflagset (enc_tkt_reply.flags, TKT_FLG_TRANSIT_POLICY_CHECKED)) {
errcode = KRB5KDC_ERR_POLICY;
status = "BAD_TRANSIT";
goto cleanup;
}
ticket_reply.enc_part2 = &enc_tkt_reply;
/*
* If we are doing user-to-user authentication, then make sure
* that the client for the second ticket matches the request
* server, and then encrypt the ticket using the session key of
* the second ticket.
*/
if (isflagset(request->kdc_options, KDC_OPT_ENC_TKT_IN_SKEY)) {
/*
* Make sure the client for the second ticket matches
* requested server.
*/
krb5_enc_tkt_part *t2enc = request->second_ticket[st_idx]->enc_part2;
krb5_principal client2 = t2enc->client;
if (!krb5_principal_compare(kdc_context, request->server, client2)) {
if ((errcode = krb5_unparse_name(kdc_context, client2, &tmp)))
tmp = 0;
if (tmp != NULL)
limit_string(tmp);
krb5_klog_syslog(LOG_INFO,
"TGS_REQ %s: 2ND_TKT_MISMATCH: "
"authtime %d, %s for %s, 2nd tkt client %s",
fromstring, authtime,
cname ? cname : "<unknown client>",
sname ? sname : "<unknown server>",
tmp ? tmp : "<unknown>");
errcode = KRB5KDC_ERR_SERVER_NOMATCH;
goto cleanup;
}
ticket_reply.enc_part.kvno = 0;
ticket_reply.enc_part.enctype = t2enc->session->enctype;
if ((errcode = krb5_encrypt_tkt_part(kdc_context, t2enc->session,
&ticket_reply))) {
status = "2ND_TKT_ENCRYPT";
goto cleanup;
}
st_idx++;
} else {
/*
* Find the server key
*/
if ((errcode = krb5_dbe_find_enctype(kdc_context, &server,
-1, /* ignore keytype */
-1, /* Ignore salttype */
0, /* Get highest kvno */
&server_key))) {
status = "FINDING_SERVER_KEY";
goto cleanup;
}
/* convert server.key into a real key (it may be encrypted
* in the database) */
if ((errcode = krb5_dbekd_decrypt_key_data(kdc_context,
&master_keyblock,
server_key, &encrypting_key,
NULL))) {
status = "DECRYPT_SERVER_KEY";
goto cleanup;
}
errcode = krb5_encrypt_tkt_part(kdc_context, &encrypting_key,
&ticket_reply);
krb5_free_keyblock_contents(kdc_context, &encrypting_key);
if (errcode) {
status = "TKT_ENCRYPT";
goto cleanup;
}
ticket_reply.enc_part.kvno = server_key->key_data_kvno;
}
/* Start assembling the response */
reply.msg_type = KRB5_TGS_REP;
reply.padata = 0; /* always */
reply.client = header_ticket->enc_part2->client;
reply.enc_part.kvno = 0; /* We are using the session key */
reply.ticket = &ticket_reply;
reply_encpart.session = &session_key;
reply_encpart.nonce = request->nonce;
/* copy the time fields EXCEPT for authtime; its location
is used for ktime */
reply_encpart.times = enc_tkt_reply.times;
reply_encpart.times.authtime = header_ticket->enc_part2->times.authtime;
/* starttime is optional, and treated as authtime if not present.
so we can nuke it if it matches */
if (enc_tkt_reply.times.starttime == enc_tkt_reply.times.authtime)
enc_tkt_reply.times.starttime = 0;
nolrentry.lr_type = KRB5_LRQ_NONE;
nolrentry.value = 0;
nolrarray[0] = &nolrentry;
nolrarray[1] = 0;
reply_encpart.last_req = nolrarray; /* not available for TGS reqs */
reply_encpart.key_exp = 0; /* ditto */
reply_encpart.flags = enc_tkt_reply.flags;
reply_encpart.server = ticket_reply.server;
/* use the session key in the ticket, unless there's a subsession key
in the AP_REQ */
reply.enc_part.enctype = subkey ? subkey->enctype :
header_ticket->enc_part2->session->enctype;
errcode = krb5_encode_kdc_rep(kdc_context, KRB5_TGS_REP, &reply_encpart,
subkey ? 1 : 0,
subkey ? subkey :
header_ticket->enc_part2->session,
&reply, response);
if (errcode) {
status = "ENCODE_KDC_REP";
} else {
status = "ISSUE";
}
memset(ticket_reply.enc_part.ciphertext.data, 0,
ticket_reply.enc_part.ciphertext.length);
free(ticket_reply.enc_part.ciphertext.data);
/* these parts are left on as a courtesy from krb5_encode_kdc_rep so we
can use them in raw form if needed. But, we don't... */
memset(reply.enc_part.ciphertext.data, 0,
reply.enc_part.ciphertext.length);
free(reply.enc_part.ciphertext.data);
cleanup:
if (status) {
const char * emsg = NULL;
if (!errcode)
rep_etypes2str(rep_etypestr, sizeof(rep_etypestr), &reply);
if (errcode)
emsg = krb5_get_error_message (kdc_context, errcode);
krb5_klog_syslog(LOG_INFO,
"TGS_REQ (%s) %s: %s: authtime %d, "
"%s%s %s for %s%s%s",
ktypestr,
fromstring, status, authtime,
!errcode ? rep_etypestr : "",
!errcode ? "," : "",
cname ? cname : "<unknown client>",
sname ? sname : "<unknown server>",
errcode ? ", " : "",
errcode ? emsg : "");
if (errcode)
krb5_free_error_message (kdc_context, emsg);
}
if (errcode) {
int got_err = 0;
if (status == 0) {
status = krb5_get_error_message (kdc_context, errcode);
got_err = 1;
}
errcode -= ERROR_TABLE_BASE_krb5;
if (errcode < 0 || errcode > 128)
errcode = KRB_ERR_GENERIC;
retval = prepare_error_tgs(request, header_ticket, errcode,
fromstring, response, status);
if (got_err) {
krb5_free_error_message (kdc_context, status);
status = 0;
}
}
if (header_ticket)
krb5_free_ticket(kdc_context, header_ticket);
if (request)
krb5_free_kdc_req(kdc_context, request);
if (cname)
free(cname);
if (sname)
free(sname);
if (nprincs)
krb5_db_free_principal(kdc_context, &server, 1);
if (session_key.contents)
krb5_free_keyblock_contents(kdc_context, &session_key);
if (newtransited)
free(enc_tkt_reply.transited.tr_contents.data);
if (subkey)
krb5_free_keyblock(kdc_context, subkey);
return retval;
}
/* Given krb5 service name in KSSL_CTX *kssl_ctx (typically "kssl"),
** and krb5 AP_REQ message & message length,
** Return Kerberos session key and client principle
** to SSL Server in KSSL_CTX *kssl_ctx.
**
** 19990702 VRS Started.
*/
krb5_error_code
kssl_sget_tkt(
/* UPDATE */ KSSL_CTX *kssl_ctx,
/* IN */ krb5_data *indata,
/* OUT */ krb5_ticket_times *ttimes,
/* OUT */ KSSL_ERR *kssl_err )
{
krb5_error_code krb5rc = KRB5KRB_ERR_GENERIC;
static krb5_context krb5context = NULL;
static krb5_auth_context krb5auth_context = NULL;
krb5_ticket *krb5ticket = NULL;
KRB5_TKTBODY *asn1ticket = NULL;
const unsigned char *p;
krb5_keytab krb5keytab = NULL;
krb5_keytab_entry kt_entry;
krb5_principal krb5server;
krb5_rcache rcache = NULL;
kssl_err_set(kssl_err, 0, "");
if (!kssl_ctx) {
kssl_err_set(kssl_err, SSL_R_KRB5_S_INIT,
"No kssl_ctx defined.\n");
goto err;
}
#ifdef KSSL_DEBUG
printf("in kssl_sget_tkt(%s)\n", kstring(kssl_ctx->service_name));
#endif /* KSSL_DEBUG */
if (!krb5context && (krb5rc = krb5_init_context(&krb5context))) {
kssl_err_set(kssl_err, SSL_R_KRB5_S_INIT,
"krb5_init_context() fails.\n");
goto err;
}
if (krb5auth_context &&
(krb5rc = krb5_auth_con_free(krb5context, krb5auth_context))) {
kssl_err_set(kssl_err, SSL_R_KRB5_S_INIT,
"krb5_auth_con_free() fails.\n");
goto err;
} else
krb5auth_context = NULL;
if (!krb5auth_context &&
(krb5rc = krb5_auth_con_init(krb5context, &krb5auth_context))) {
kssl_err_set(kssl_err, SSL_R_KRB5_S_INIT,
"krb5_auth_con_init() fails.\n");
goto err;
}
if ((krb5rc = krb5_auth_con_getrcache(krb5context, krb5auth_context,
&rcache))) {
kssl_err_set(kssl_err, SSL_R_KRB5_S_INIT,
"krb5_auth_con_getrcache() fails.\n");
goto err;
}
if ((krb5rc = krb5_sname_to_principal(krb5context, NULL,
(kssl_ctx->service_name) ? kssl_ctx->service_name : KRB5SVC,
KRB5_NT_SRV_HST, &krb5server)) != 0) {
kssl_err_set(kssl_err, SSL_R_KRB5_S_INIT,
"krb5_sname_to_principal() fails.\n");
goto err;
}
if (rcache == NULL) {
if ((krb5rc = krb5_get_server_rcache(krb5context,
krb5_princ_component(krb5context, krb5server, 0),
&rcache))) {
kssl_err_set(kssl_err, SSL_R_KRB5_S_INIT,
"krb5_get_server_rcache() fails.\n");
goto err;
}
}
if ((krb5rc = krb5_auth_con_setrcache(krb5context, krb5auth_context,
rcache))) {
kssl_err_set(kssl_err, SSL_R_KRB5_S_INIT,
"krb5_auth_con_setrcache() fails.\n");
goto err;
}
/* kssl_ctx->keytab_file == NULL ==> use Kerberos default
*/
if (kssl_ctx->keytab_file) {
krb5rc = krb5_kt_resolve(krb5context, kssl_ctx->keytab_file,
&krb5keytab);
if (krb5rc) {
kssl_err_set(kssl_err, SSL_R_KRB5_S_INIT,
"krb5_kt_resolve() fails.\n");
goto err;
}
} else {
krb5rc = krb5_kt_default(krb5context, &krb5keytab);
if (krb5rc) {
kssl_err_set(kssl_err, SSL_R_KRB5_S_INIT,
"krb5_kt_default() fails.\n");
goto err;
}
}
/* Actual Kerberos5 krb5_recvauth() has initial conversation here
** o check KRB5_SENDAUTH_BADAUTHVERS
** unless KRB5_RECVAUTH_SKIP_VERSION
** o check KRB5_SENDAUTH_BADAPPLVERS
** o send "0" msg if all OK
*/
/* 20010411 was using AP_REQ instead of true KerberosWrapper
**
** if ((krb5rc = krb5_rd_req(krb5context, &krb5auth_context,
** &krb5in_data, krb5server, krb5keytab,
** &ap_option, &krb5ticket)) != 0) { Error }
*/
p = (unsigned char *)indata->data;
if ((asn1ticket = (KRB5_TKTBODY *) d2i_KRB5_TICKET(NULL, &p,
(long)indata->length)) == NULL) {
(void) snprintf(kssl_err->text, KSSL_ERR_MAX,
"d2i_KRB5_TICKET() ASN.1 decode failure.\n");
kssl_err->reason = SSL_R_KRB5_S_RD_REQ;
goto err;
}
/* Was: krb5rc = krb5_decode_ticket(krb5in_data,&krb5ticket)) != 0) */
if ((krb5rc = kssl_TKT2tkt(krb5context, asn1ticket, &krb5ticket,
kssl_err)) != 0) {
(void) snprintf(kssl_err->text, KSSL_ERR_MAX,
"Error converting ASN.1 ticket to krb5_ticket.\n");
kssl_err->reason = SSL_R_KRB5_S_RD_REQ;
goto err;
}
if (!krb5_principal_compare(krb5context, krb5server,
krb5ticket->server)) {
krb5rc = KRB5_PRINC_NOMATCH;
(void) snprintf(kssl_err->text, KSSL_ERR_MAX,
"server principal != ticket principal\n");
kssl_err->reason = SSL_R_KRB5_S_RD_REQ;
goto err;
}
if ((krb5rc = krb5_kt_get_entry(krb5context, krb5keytab,
krb5ticket->server, krb5ticket->enc_part.kvno,
krb5ticket->enc_part.enctype, &kt_entry)) != 0) {
(void) snprintf(kssl_err->text, KSSL_ERR_MAX,
"krb5_kt_get_entry() fails with %x.\n", krb5rc);
kssl_err->reason = SSL_R_KRB5_S_RD_REQ;
goto err;
}
if ((krb5rc = krb5_decrypt_tkt_part(krb5context, &kt_entry.key,
krb5ticket)) != 0) {
(void) snprintf(kssl_err->text, KSSL_ERR_MAX,
"krb5_decrypt_tkt_part() failed.\n");
kssl_err->reason = SSL_R_KRB5_S_RD_REQ;
goto err;
} else {
krb5_kt_free_entry(krb5context, &kt_entry);
#ifdef KSSL_DEBUG
{
int i;
krb5_address **paddr = krb5ticket->enc_part2->caddrs;
printf("Decrypted ticket fields:\n");
printf("\tflags: %X, transit-type: %X",
krb5ticket->enc_part2->flags,
krb5ticket->enc_part2->transited.tr_type);
print_krb5_data("\ttransit-data: ",
&(krb5ticket->enc_part2->transited.tr_contents));
printf("\tcaddrs: %p, authdata: %p\n",
krb5ticket->enc_part2->caddrs,
krb5ticket->enc_part2->authorization_data);
if (paddr) {
printf("\tcaddrs:\n");
for (i = 0; paddr[i] != NULL; i++) {
krb5_data d;
d.length = paddr[i]->length;
d.data = paddr[i]->contents;
print_krb5_data("\t\tIP: ", &d);
}
}
printf("\tstart/auth/end times: %d / %d / %d\n",
krb5ticket->enc_part2->times.starttime,
krb5ticket->enc_part2->times.authtime,
krb5ticket->enc_part2->times.endtime);
}
#endif /* KSSL_DEBUG */
}
krb5rc = KRB5_NO_TKT_SUPPLIED;
if (!krb5ticket || !krb5ticket->enc_part2 ||
!krb5ticket->enc_part2->client ||
!krb5ticket->enc_part2->client->data ||
!krb5ticket->enc_part2->session) {
kssl_err_set(kssl_err, SSL_R_KRB5_S_BAD_TICKET,
"bad ticket from krb5_rd_req.\n");
} else if (kssl_ctx_setprinc(kssl_ctx, KSSL_CLIENT,
&krb5ticket->enc_part2->client->realm,
krb5ticket->enc_part2->client->data,
krb5ticket->enc_part2->client->length)) {
kssl_err_set(kssl_err, SSL_R_KRB5_S_BAD_TICKET,
"kssl_ctx_setprinc() fails.\n");
} else if (kssl_ctx_setkey(kssl_ctx, krb5ticket->enc_part2->session)) {
kssl_err_set(kssl_err, SSL_R_KRB5_S_BAD_TICKET,
"kssl_ctx_setkey() fails.\n");
} else if (krb5ticket->enc_part2->flags & TKT_FLG_INVALID) {
krb5rc = KRB5KRB_AP_ERR_TKT_INVALID;
kssl_err_set(kssl_err, SSL_R_KRB5_S_BAD_TICKET,
"invalid ticket from krb5_rd_req.\n");
} else
krb5rc = 0;
kssl_ctx->enctype = krb5ticket->enc_part.enctype;
ttimes->authtime = krb5ticket->enc_part2->times.authtime;
ttimes->starttime = krb5ticket->enc_part2->times.starttime;
ttimes->endtime = krb5ticket->enc_part2->times.endtime;
ttimes->renew_till = krb5ticket->enc_part2->times.renew_till;
err:
#ifdef KSSL_DEBUG
kssl_ctx_show(kssl_ctx);
#endif /* KSSL_DEBUG */
if (asn1ticket)
KRB5_TICKET_free((KRB5_TICKET *) asn1ticket);
if (krb5keytab)
krb5_kt_close(krb5context, krb5keytab);
if (krb5ticket)
krb5_free_ticket(krb5context, krb5ticket);
if (krb5server)
krb5_free_principal(krb5context, krb5server);
return (krb5rc);
}
tkt_test_1()
{
krb5_data *data;
krb5_ticket tk_in, *tk_out;
krb5_keyblock sess_k, serv_k, *nsess;
krb5_enc_tkt_part tk_in_enc;
int code;
krb5_address *addr_list[2];
krb5_address addr_1;
static krb5_octet ip_addr_1[4] = { 18, 72, 0, 122 };
char *out;
/*
* fill in some values on the "in" side of the ticket
*/
code = krb5_parse_name ("server/test/[email protected]", &tk_in.server);
if (code != 0) {
com_err("tkt_test_1", code, " parsing server principal");
return;
}
serv_k.enctype = 1; /* XXX symbolic constant */
serv_k.length = 8; /* XXX symbolic constant */
serv_k.contents = key_one;
sess_k.enctype = 1; /* XXX symbolic constant */
sess_k.length = 8; /* XXX symbolic constant */
sess_k.contents = key_two;
tk_in.etype = 1; /* XXX symbolic constant here */
tk_in.skvno = 4;
tk_in.enc_part2 = &tk_in_enc;
tk_in_enc.flags = 0x11;
tk_in_enc.session = &sess_k;
tk_in_enc.times.authtime = 42;
tk_in_enc.times.starttime = 43;
tk_in_enc.times.endtime = 44;
code = krb5_parse_name ("client/test/[email protected]", &tk_in_enc.client);
if (code != 0) {
com_err("tkt_test_1", code, " parsing client principal");
return;
}
tk_in_enc.transited.length = 0;
addr_1.addrtype = ADDRTYPE_INET; /* XXX should be KRB5_ADDR... */
addr_1.length = 4;
addr_1.contents = ip_addr_1;
addr_list[0] = &addr_1;
addr_list[1] = 0;
tk_in_enc.caddrs = addr_list;
tk_in_enc.authorization_data = 0;
code = krb5_encrypt_tkt_part(&serv_k, &tk_in);
if (code != 0) {
com_err ("tkt_test_1", code, " encrypting ticket");
return;
}
data = 0;
code = krb5_encode_ticket (&tk_in, &data);
if (code != 0) {
com_err ("tkt_test_1", code, " encoding ticket");
return;
}
dump_data(data);
tk_out = 0;
code = krb5_decode_ticket (data, &tk_out);
if (code != 0) {
com_err ("tkt_test_1", code, "decoding ticket");
return;
}
/* check the plaintext values */
if (tk_out->etype != 1) {
com_err ("tkt_test_1", 0, "wrong etype");
return;
}
if (tk_out->skvno != 4) {
com_err ("tkt_test_1", 0, "wrong kvno");
return;
}
code = krb5_unparse_name(tk_out->server, &out);
if (code != 0) {
com_err ("tkt_test_1", code, "couldn't unparse server principal");
return;
}
if (strcmp (out, "server/test/[email protected]") != 0) {
com_err("tkt_test_1", 0, "wrong server principal");
return;
}
free(out);
out = 0;
/* decode the ciphertext */
code = krb5_decrypt_tkt_part (&serv_k, tk_out);
if (code != 0) {
com_err ("tkt_test_1", code, "while decrypting ticket");
return;
}
/* check the contents */
if (tk_out->enc_part2->flags != 0x11) {
com_err("tkt_test_1", 0, "wrong flags");
return;
}
nsess = tk_out->enc_part2->session;
if (nsess->enctype != 1) {
com_err("tkt_test_1", 0, "wrong session key type");
return;
}
if (nsess->length != 8) {
com_err("tkt_test_1", 0, "wrong session key length");
return;
}
if (memcmp(nsess->contents, key_two, 8) != 0) {
com_err("tkt_test_1", 0, "wrong session key contents");
return;
}
code = krb5_unparse_name(tk_out->enc_part2->client, &out);
if (code != 0) {
com_err ("tkt_test_1", code, "couldn't unparse client principal");
return;
}
if (strcmp (out, "client/test/[email protected]") != 0) {
com_err("tkt_test_1", 0, "wrong client principal");
return;
}
free(out);
out = 0;
if (tk_out->enc_part2->transited.length != 0) {
com_err("tkt_test_1", 0, "wrong transited length");
return;
}
/* XXX should check address here, too */
/* XXX should check times here */
/* XXX should check auth. data here */
printf("test 1 passed\n");
}
