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;
}
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;
}
int main (int argc, char *argv[]) {
const char *me;
krb5_data crealm, srealm, transit;
krb5_error_code r;
int expand_only = 0;
me = strrchr (argv[0], '/');
me = me ? me+1 : argv[0];
while (argc > 3 && argv[1][0] == '-') {
if (!strcmp ("-v", argv[1]))
verbose++, argc--, argv++;
else if (!strcmp ("-x", argv[1]))
expand_only++, argc--, argv++;
else
goto usage;
}
if (argc != 4) {
usage:
printf ("usage: %s [-v] [-x] clientRealm serverRealm transitEncoding\n",
me);
return 1;
}
crealm.data = argv[1];
crealm.length = strlen(argv[1]);
srealm.data = argv[2];
srealm.length = strlen(argv[2]);
transit.data = argv[3];
transit.length = strlen(argv[3]);
if (expand_only) {
printf ("client realm: %s\n", argv[1]);
printf ("server realm: %s\n", argv[2]);
printf ("transit enc.: %s\n", argv[3]);
if (argv[3][0] == 0) {
printf ("no other realms transited\n");
return 0;
}
r = foreach_realm (print_a_realm, NULL, &crealm, &srealm, &transit);
if (r)
printf ("--> returned error %ld\n", (long) r);
return r != 0;
} else {
/* Actually check the values against the supplied krb5.conf file. */
krb5_context ctx;
r = krb5_init_context (&ctx);
if (r) {
com_err (me, r, "initializing krb5 context");
return 1;
}
r = krb5_check_transited_list (ctx, &transit, &crealm, &srealm);
if (r == KRB5KRB_AP_ERR_ILL_CR_TKT) {
printf ("NO\n");
} else if (r == 0) {
printf ("YES\n");
} else {
printf ("kablooey!\n");
com_err (me, r, "checking transited-realm list");
return 1;
}
return 0;
}
}
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;
}
