krb5_error_code _kdc_as_rep(krb5_context context, krb5_kdc_configuration *config, KDC_REQ *req, const krb5_data *req_buffer, krb5_data *reply, const char *from, struct sockaddr *from_addr, int datagram_reply) { KDC_REQ_BODY *b = &req->req_body; AS_REP rep; KDCOptions f = b->kdc_options; hdb_entry_ex *client = NULL, *server = NULL; HDB *clientdb; krb5_enctype setype, sessionetype; krb5_data e_data; EncTicketPart et; EncKDCRepPart ek; krb5_principal client_princ = NULL, server_princ = NULL; char *client_name = NULL, *server_name = NULL; krb5_error_code ret = 0; const char *e_text = NULL; krb5_crypto crypto; Key *ckey, *skey; EncryptionKey *reply_key = NULL, session_key; int flags = HDB_F_FOR_AS_REQ; #ifdef PKINIT pk_client_params *pkp = NULL; #endif memset(&rep, 0, sizeof(rep)); memset(&session_key, 0, sizeof(session_key)); krb5_data_zero(&e_data); ALLOC(rep.padata); rep.padata->len = 0; rep.padata->val = NULL; if (f.canonicalize) flags |= HDB_F_CANON; if(b->sname == NULL){ ret = KRB5KRB_ERR_GENERIC; e_text = "No server in request"; } else{ ret = _krb5_principalname2krb5_principal (context, &server_princ, *(b->sname), b->realm); if (ret == 0) ret = krb5_unparse_name(context, server_princ, &server_name); } if (ret) { kdc_log(context, config, 0, "AS-REQ malformed server name from %s", from); goto out; } if(b->cname == NULL){ ret = KRB5KRB_ERR_GENERIC; e_text = "No client in request"; } else { ret = _krb5_principalname2krb5_principal (context, &client_princ, *(b->cname), b->realm); if (ret) goto out; ret = krb5_unparse_name(context, client_princ, &client_name); } if (ret) { kdc_log(context, config, 0, "AS-REQ malformed client name from %s", from); goto out; } kdc_log(context, config, 0, "AS-REQ %s from %s for %s", client_name, from, server_name); /* * */ if (_kdc_is_anonymous(context, client_princ)) { if (!b->kdc_options.request_anonymous) { kdc_log(context, config, 0, "Anonymous ticket w/o anonymous flag"); ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN; goto out; } } else if (b->kdc_options.request_anonymous) { kdc_log(context, config, 0, "Request for a anonymous ticket with non " "anonymous client name: %s", client_name); ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN; goto out; } /* * */ ret = _kdc_db_fetch(context, config, client_princ, HDB_F_GET_CLIENT | flags, NULL, &clientdb, &client); if(ret == HDB_ERR_NOT_FOUND_HERE) { kdc_log(context, config, 5, "client %s does not have secrets at this KDC, need to proxy", client_name); goto out; } else if(ret){ const char *msg = krb5_get_error_message(context, ret); kdc_log(context, config, 0, "UNKNOWN -- %s: %s", client_name, msg); krb5_free_error_message(context, msg); ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN; goto out; } ret = _kdc_db_fetch(context, config, server_princ, HDB_F_GET_SERVER|HDB_F_GET_KRBTGT | flags, NULL, NULL, &server); if(ret == HDB_ERR_NOT_FOUND_HERE) { kdc_log(context, config, 5, "target %s does not have secrets at this KDC, need to proxy", server_name); goto out; } else if(ret){ const char *msg = krb5_get_error_message(context, ret); kdc_log(context, config, 0, "UNKNOWN -- %s: %s", server_name, msg); krb5_free_error_message(context, msg); ret = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN; goto out; } memset(&et, 0, sizeof(et)); memset(&ek, 0, sizeof(ek)); /* * Select a session enctype from the list of the crypto system * supported enctypes that is supported by the client and is one of * the enctype of the enctype of the service (likely krbtgt). * * The latter is used as a hint of what enctypes all KDC support, * to make sure a newer version of KDC won't generate a session * enctype that an older version of a KDC in the same realm can't * decrypt. */ ret = _kdc_find_etype(context, config->as_use_strongest_session_key, FALSE, client, b->etype.val, b->etype.len, &sessionetype, NULL); if (ret) { kdc_log(context, config, 0, "Client (%s) from %s has no common enctypes with KDC " "to use for the session key", client_name, from); goto out; } /* * But if the KDC admin is paranoid and doesn't want to have "not * the best" enctypes on the krbtgt, lets save the best pick from * the client list and hope that that will work for any other * KDCs. */ /* * Pre-auth processing */ if(req->padata){ int i; const PA_DATA *pa; int found_pa = 0; log_patypes(context, config, req->padata); #ifdef PKINIT kdc_log(context, config, 5, "Looking for PKINIT pa-data -- %s", client_name); e_text = "No PKINIT PA found"; i = 0; pa = _kdc_find_padata(req, &i, KRB5_PADATA_PK_AS_REQ); if (pa == NULL) { i = 0; pa = _kdc_find_padata(req, &i, KRB5_PADATA_PK_AS_REQ_WIN); } if (pa) { char *client_cert = NULL; ret = _kdc_pk_rd_padata(context, config, req, pa, client, &pkp); if (ret) { ret = KRB5KRB_AP_ERR_BAD_INTEGRITY; kdc_log(context, config, 5, "Failed to decode PKINIT PA-DATA -- %s", client_name); goto ts_enc; } if (ret == 0 && pkp == NULL) goto ts_enc; ret = _kdc_pk_check_client(context, config, clientdb, client, pkp, &client_cert); if (ret) { e_text = "PKINIT certificate not allowed to " "impersonate principal"; _kdc_pk_free_client_param(context, pkp); kdc_log(context, config, 0, "%s", e_text); pkp = NULL; goto out; } found_pa = 1; et.flags.pre_authent = 1; kdc_log(context, config, 0, "PKINIT pre-authentication succeeded -- %s using %s", client_name, client_cert); free(client_cert); if (pkp) goto preauth_done; } ts_enc: #endif if (client->entry.flags.locked_out) { ret = KRB5KDC_ERR_CLIENT_REVOKED; kdc_log(context, config, 0, "Client (%s) is locked out", client_name); goto out; } kdc_log(context, config, 5, "Looking for ENC-TS pa-data -- %s", client_name); i = 0; e_text = "No ENC-TS found"; while((pa = _kdc_find_padata(req, &i, KRB5_PADATA_ENC_TIMESTAMP))){ krb5_data ts_data; PA_ENC_TS_ENC p; size_t len; EncryptedData enc_data; Key *pa_key; char *str; found_pa = 1; if (b->kdc_options.request_anonymous) { ret = KRB5KRB_AP_ERR_BAD_INTEGRITY; kdc_log(context, config, 0, "ENC-TS doesn't support anon"); goto out; } ret = decode_EncryptedData(pa->padata_value.data, pa->padata_value.length, &enc_data, &len); if (ret) { ret = KRB5KRB_AP_ERR_BAD_INTEGRITY; kdc_log(context, config, 5, "Failed to decode PA-DATA -- %s", client_name); goto out; } ret = hdb_enctype2key(context, &client->entry, enc_data.etype, &pa_key); if(ret){ char *estr; e_text = "No key matches pa-data"; ret = KRB5KDC_ERR_ETYPE_NOSUPP; if(krb5_enctype_to_string(context, enc_data.etype, &estr)) estr = NULL; if(estr == NULL) kdc_log(context, config, 5, "No client key matching pa-data (%d) -- %s", enc_data.etype, client_name); else kdc_log(context, config, 5, "No client key matching pa-data (%s) -- %s", estr, client_name); free(estr); free_EncryptedData(&enc_data); continue; } try_next_key: ret = krb5_crypto_init(context, &pa_key->key, 0, &crypto); if (ret) { const char *msg = krb5_get_error_message(context, ret); kdc_log(context, config, 0, "krb5_crypto_init failed: %s", msg); krb5_free_error_message(context, msg); free_EncryptedData(&enc_data); continue; } ret = krb5_decrypt_EncryptedData (context, crypto, KRB5_KU_PA_ENC_TIMESTAMP, &enc_data, &ts_data); krb5_crypto_destroy(context, crypto); /* * Since the user might have several keys with the same * enctype but with diffrent salting, we need to try all * the keys with the same enctype. */ if(ret){ krb5_error_code ret2; const char *msg = krb5_get_error_message(context, ret); ret2 = krb5_enctype_to_string(context, pa_key->key.keytype, &str); if (ret2) str = NULL; kdc_log(context, config, 5, "Failed to decrypt PA-DATA -- %s " "(enctype %s) error %s", client_name, str ? str : "unknown enctype", msg); krb5_free_error_message(context, msg); free(str); if(hdb_next_enctype2key(context, &client->entry, enc_data.etype, &pa_key) == 0) goto try_next_key; e_text = "Failed to decrypt PA-DATA"; free_EncryptedData(&enc_data); if (clientdb->hdb_auth_status) (clientdb->hdb_auth_status)(context, clientdb, client, HDB_AUTH_WRONG_PASSWORD); ret = KRB5KDC_ERR_PREAUTH_FAILED; continue; } free_EncryptedData(&enc_data); ret = decode_PA_ENC_TS_ENC(ts_data.data, ts_data.length, &p, &len); krb5_data_free(&ts_data); if(ret){ e_text = "Failed to decode PA-ENC-TS-ENC"; ret = KRB5KDC_ERR_PREAUTH_FAILED; kdc_log(context, config, 5, "Failed to decode PA-ENC-TS_ENC -- %s", client_name); continue; } free_PA_ENC_TS_ENC(&p); if (abs(kdc_time - p.patimestamp) > context->max_skew) { char client_time[100]; krb5_format_time(context, p.patimestamp, client_time, sizeof(client_time), TRUE); ret = KRB5KRB_AP_ERR_SKEW; kdc_log(context, config, 0, "Too large time skew, " "client time %s is out by %u > %u seconds -- %s", client_time, (unsigned)abs(kdc_time - p.patimestamp), context->max_skew, client_name); /* * The following is needed to make windows clients to * retry using the timestamp in the error message, if * there is a e_text, they become unhappy. */ e_text = NULL; goto out; } et.flags.pre_authent = 1; set_salt_padata(rep.padata, pa_key->salt); reply_key = &pa_key->key; ret = krb5_enctype_to_string(context, pa_key->key.keytype, &str); if (ret) str = NULL; kdc_log(context, config, 2, "ENC-TS Pre-authentication succeeded -- %s using %s", client_name, str ? str : "unknown enctype"); free(str); break; } #ifdef PKINIT preauth_done: #endif if(found_pa == 0 && config->require_preauth) goto use_pa; /* We come here if we found a pa-enc-timestamp, but if there was some problem with it, other than too large skew */ if(found_pa && et.flags.pre_authent == 0){ kdc_log(context, config, 0, "%s -- %s", e_text, client_name); e_text = NULL; goto out; } }else if (config->require_preauth || b->kdc_options.request_anonymous /* hack to force anon */ || client->entry.flags.require_preauth || server->entry.flags.require_preauth) { METHOD_DATA method_data; PA_DATA *pa; unsigned char *buf; size_t len; use_pa: method_data.len = 0; method_data.val = NULL; ret = realloc_method_data(&method_data); if (ret) { free_METHOD_DATA(&method_data); goto out; } pa = &method_data.val[method_data.len-1]; pa->padata_type = KRB5_PADATA_ENC_TIMESTAMP; pa->padata_value.length = 0; pa->padata_value.data = NULL; #ifdef PKINIT ret = realloc_method_data(&method_data); if (ret) { free_METHOD_DATA(&method_data); goto out; } pa = &method_data.val[method_data.len-1]; pa->padata_type = KRB5_PADATA_PK_AS_REQ; pa->padata_value.length = 0; pa->padata_value.data = NULL; ret = realloc_method_data(&method_data); if (ret) { free_METHOD_DATA(&method_data); goto out; } pa = &method_data.val[method_data.len-1]; pa->padata_type = KRB5_PADATA_PK_AS_REQ_WIN; pa->padata_value.length = 0; pa->padata_value.data = NULL; #endif /* * If there is a client key, send ETYPE_INFO{,2} */ ret = _kdc_find_etype(context, config->preauth_use_strongest_session_key, TRUE, client, b->etype.val, b->etype.len, NULL, &ckey); if (ret == 0) { /* * RFC4120 requires: * - If the client only knows about old enctypes, then send * both info replies (we send 'info' first in the list). * - If the client is 'modern', because it knows about 'new' * enctype types, then only send the 'info2' reply. * * Before we send the full list of etype-info data, we pick * the client key we would have used anyway below, just pick * that instead. */ if (older_enctype(ckey->key.keytype)) { ret = get_pa_etype_info(context, config, &method_data, ckey); if (ret) { free_METHOD_DATA(&method_data); goto out; } } ret = get_pa_etype_info2(context, config, &method_data, ckey); if (ret) { free_METHOD_DATA(&method_data); goto out; } } ASN1_MALLOC_ENCODE(METHOD_DATA, buf, len, &method_data, &len, ret); free_METHOD_DATA(&method_data); e_data.data = buf; e_data.length = len; e_text ="Need to use PA-ENC-TIMESTAMP/PA-PK-AS-REQ", ret = KRB5KDC_ERR_PREAUTH_REQUIRED; kdc_log(context, config, 0, "No preauth found, returning PREAUTH-REQUIRED -- %s", client_name); goto out; } /* * Verify flags after the user been required to prove its identity * with in a preauth mech. */ ret = _kdc_check_access(context, config, client, client_name, server, server_name, req, &e_data); if(ret) goto out; if (clientdb->hdb_auth_status) (clientdb->hdb_auth_status)(context, clientdb, client, HDB_AUTH_SUCCESS); /* * Selelct the best encryption type for the KDC with out regard to * the client since the client never needs to read that data. */ ret = _kdc_get_preferred_key(context, config, server, server_name, &setype, &skey); if(ret) goto out; if(f.renew || f.validate || f.proxy || f.forwarded || f.enc_tkt_in_skey || (f.request_anonymous && !config->allow_anonymous)) { ret = KRB5KDC_ERR_BADOPTION; e_text = "Bad KDC options"; kdc_log(context, config, 0, "Bad KDC options -- %s", client_name); goto out; } rep.pvno = 5; rep.msg_type = krb_as_rep; ret = copy_Realm(&client->entry.principal->realm, &rep.crealm); if (ret) goto out; ret = _krb5_principal2principalname(&rep.cname, client->entry.principal); if (ret) goto out; rep.ticket.tkt_vno = 5; copy_Realm(&server->entry.principal->realm, &rep.ticket.realm); _krb5_principal2principalname(&rep.ticket.sname, server->entry.principal); /* java 1.6 expects the name to be the same type, lets allow that * uncomplicated name-types. */ #define CNT(sp,t) (((sp)->sname->name_type) == KRB5_NT_##t) if (CNT(b, UNKNOWN) || CNT(b, PRINCIPAL) || CNT(b, SRV_INST) || CNT(b, SRV_HST) || CNT(b, SRV_XHST)) rep.ticket.sname.name_type = b->sname->name_type; #undef CNT et.flags.initial = 1; if(client->entry.flags.forwardable && server->entry.flags.forwardable) et.flags.forwardable = f.forwardable; else if (f.forwardable) { e_text = "Ticket may not be forwardable"; ret = KRB5KDC_ERR_POLICY; kdc_log(context, config, 0, "Ticket may not be forwardable -- %s", client_name); goto out; } if(client->entry.flags.proxiable && server->entry.flags.proxiable) et.flags.proxiable = f.proxiable; else if (f.proxiable) { e_text = "Ticket may not be proxiable"; ret = KRB5KDC_ERR_POLICY; kdc_log(context, config, 0, "Ticket may not be proxiable -- %s", client_name); goto out; } if(client->entry.flags.postdate && server->entry.flags.postdate) et.flags.may_postdate = f.allow_postdate; else if (f.allow_postdate){ e_text = "Ticket may not be postdate"; ret = KRB5KDC_ERR_POLICY; kdc_log(context, config, 0, "Ticket may not be postdatable -- %s", client_name); goto out; } /* check for valid set of addresses */ if(!_kdc_check_addresses(context, config, b->addresses, from_addr)) { e_text = "Bad address list in requested"; ret = KRB5KRB_AP_ERR_BADADDR; kdc_log(context, config, 0, "Bad address list requested -- %s", client_name); goto out; } ret = copy_PrincipalName(&rep.cname, &et.cname); if (ret) goto out; ret = copy_Realm(&rep.crealm, &et.crealm); if (ret) goto out; { time_t start; time_t t; start = et.authtime = kdc_time; if(f.postdated && req->req_body.from){ ALLOC(et.starttime); start = *et.starttime = *req->req_body.from; et.flags.invalid = 1; et.flags.postdated = 1; /* XXX ??? */ } _kdc_fix_time(&b->till); t = *b->till; /* be careful not overflowing */ if(client->entry.max_life) t = start + min(t - start, *client->entry.max_life); if(server->entry.max_life) t = start + min(t - start, *server->entry.max_life); #if 0 t = min(t, start + realm->max_life); #endif et.endtime = t; if(f.renewable_ok && et.endtime < *b->till){ f.renewable = 1; if(b->rtime == NULL){ ALLOC(b->rtime); *b->rtime = 0; } if(*b->rtime < *b->till) *b->rtime = *b->till; } if(f.renewable && b->rtime){ t = *b->rtime; if(t == 0) t = MAX_TIME; if(client->entry.max_renew) t = start + min(t - start, *client->entry.max_renew); if(server->entry.max_renew) t = start + min(t - start, *server->entry.max_renew); #if 0 t = min(t, start + realm->max_renew); #endif ALLOC(et.renew_till); *et.renew_till = t; et.flags.renewable = 1; } } if (f.request_anonymous) et.flags.anonymous = 1; if(b->addresses){ ALLOC(et.caddr); copy_HostAddresses(b->addresses, et.caddr); } et.transited.tr_type = DOMAIN_X500_COMPRESS; krb5_data_zero(&et.transited.contents); /* The MIT ASN.1 library (obviously) doesn't tell lengths encoded * as 0 and as 0x80 (meaning indefinite length) apart, and is thus * incapable of correctly decoding SEQUENCE OF's of zero length. * * To fix this, always send at least one no-op last_req * * If there's a pw_end or valid_end we will use that, * otherwise just a dummy lr. */ ek.last_req.val = malloc(2 * sizeof(*ek.last_req.val)); if (ek.last_req.val == NULL) { ret = ENOMEM; goto out; } ek.last_req.len = 0; if (client->entry.pw_end && (config->kdc_warn_pwexpire == 0 || kdc_time + config->kdc_warn_pwexpire >= *client->entry.pw_end)) { ek.last_req.val[ek.last_req.len].lr_type = LR_PW_EXPTIME; ek.last_req.val[ek.last_req.len].lr_value = *client->entry.pw_end; ++ek.last_req.len; } if (client->entry.valid_end) { ek.last_req.val[ek.last_req.len].lr_type = LR_ACCT_EXPTIME; ek.last_req.val[ek.last_req.len].lr_value = *client->entry.valid_end; ++ek.last_req.len; } if (ek.last_req.len == 0) { ek.last_req.val[ek.last_req.len].lr_type = LR_NONE; ek.last_req.val[ek.last_req.len].lr_value = 0; ++ek.last_req.len; } ek.nonce = b->nonce; if (client->entry.valid_end || client->entry.pw_end) { ALLOC(ek.key_expiration); if (client->entry.valid_end) { if (client->entry.pw_end) *ek.key_expiration = min(*client->entry.valid_end, *client->entry.pw_end); else *ek.key_expiration = *client->entry.valid_end; } else *ek.key_expiration = *client->entry.pw_end; } else ek.key_expiration = NULL; ek.flags = et.flags; ek.authtime = et.authtime; if (et.starttime) { ALLOC(ek.starttime); *ek.starttime = *et.starttime; } ek.endtime = et.endtime; if (et.renew_till) { ALLOC(ek.renew_till); *ek.renew_till = *et.renew_till; } copy_Realm(&rep.ticket.realm, &ek.srealm); copy_PrincipalName(&rep.ticket.sname, &ek.sname); if(et.caddr){ ALLOC(ek.caddr); copy_HostAddresses(et.caddr, ek.caddr); } #if PKINIT if (pkp) { e_text = "Failed to build PK-INIT reply"; ret = _kdc_pk_mk_pa_reply(context, config, pkp, client, sessionetype, req, req_buffer, &reply_key, &et.key, rep.padata); if (ret) goto out; ret = _kdc_add_inital_verified_cas(context, config, pkp, &et); if (ret) goto out; } else #endif { ret = krb5_generate_random_keyblock(context, sessionetype, &et.key); if (ret) goto out; } if (reply_key == NULL) { e_text = "Client have no reply key"; ret = KRB5KDC_ERR_CLIENT_NOTYET; goto out; } ret = copy_EncryptionKey(&et.key, &ek.key); if (ret) goto out; if (rep.padata->len == 0) { free(rep.padata); rep.padata = NULL; } /* Add the PAC */ if (send_pac_p(context, req)) { krb5_pac p = NULL; krb5_data data; ret = _kdc_pac_generate(context, client, &p); if (ret) { kdc_log(context, config, 0, "PAC generation failed for -- %s", client_name); goto out; } if (p != NULL) { ret = _krb5_pac_sign(context, p, et.authtime, client->entry.principal, &skey->key, /* Server key */ &skey->key, /* FIXME: should be krbtgt key */ &data); krb5_pac_free(context, p); if (ret) { kdc_log(context, config, 0, "PAC signing failed for -- %s", client_name); goto out; } ret = _kdc_tkt_add_if_relevant_ad(context, &et, KRB5_AUTHDATA_WIN2K_PAC, &data); krb5_data_free(&data); if (ret) goto out; } } _kdc_log_timestamp(context, config, "AS-REQ", et.authtime, et.starttime, et.endtime, et.renew_till); /* do this as the last thing since this signs the EncTicketPart */ ret = _kdc_add_KRB5SignedPath(context, config, server, setype, client->entry.principal, NULL, NULL, &et); if (ret) goto out; log_as_req(context, config, reply_key->keytype, setype, b); ret = _kdc_encode_reply(context, config, &rep, &et, &ek, setype, server->entry.kvno, &skey->key, client->entry.kvno, reply_key, 0, &e_text, reply); free_EncTicketPart(&et); free_EncKDCRepPart(&ek); if (ret) goto out; /* */ if (datagram_reply && reply->length > config->max_datagram_reply_length) { krb5_data_free(reply); ret = KRB5KRB_ERR_RESPONSE_TOO_BIG; e_text = "Reply packet too large"; } out: free_AS_REP(&rep); if(ret != 0 && ret != HDB_ERR_NOT_FOUND_HERE){ krb5_mk_error(context, ret, e_text, (e_data.data ? &e_data : NULL), client_princ, server_princ, NULL, NULL, reply); ret = 0; } #ifdef PKINIT if (pkp) _kdc_pk_free_client_param(context, pkp); #endif if (e_data.data) free(e_data.data); if (client_princ) krb5_free_principal(context, client_princ); free(client_name); if (server_princ) krb5_free_principal(context, server_princ); free(server_name); if(client) _kdc_free_ent(context, client); if(server) _kdc_free_ent(context, server); return ret; }
krb5_error_code _kdc_as_rep(krb5_context context, krb5_kdc_configuration *config, KDC_REQ *req, const krb5_data *req_buffer, krb5_data *reply, const char *from, struct sockaddr *from_addr, int datagram_reply) { KDC_REQ_BODY *b = &req->req_body; AS_REP rep; KDCOptions f = b->kdc_options; hdb_entry_ex *client = NULL, *server = NULL; krb5_enctype cetype, setype, sessionetype; krb5_data e_data; EncTicketPart et; EncKDCRepPart ek; krb5_principal client_princ = NULL, server_princ = NULL; char *client_name = NULL, *server_name = NULL; krb5_error_code ret = 0; const char *e_text = NULL; krb5_crypto crypto; Key *ckey, *skey; EncryptionKey *reply_key; int flags = 0; #ifdef PKINIT pk_client_params *pkp = NULL; #endif memset(&rep, 0, sizeof(rep)); krb5_data_zero(&e_data); if (f.canonicalize) flags |= HDB_F_CANON; if(b->sname == NULL){ ret = KRB5KRB_ERR_GENERIC; e_text = "No server in request"; } else{ ret = _krb5_principalname2krb5_principal (context, &server_princ, *(b->sname), b->realm); if (ret == 0) ret = krb5_unparse_name(context, server_princ, &server_name); } if (ret) { kdc_log(context, config, 0, "AS-REQ malformed server name from %s", from); goto out; } if(b->cname == NULL){ ret = KRB5KRB_ERR_GENERIC; e_text = "No client in request"; } else { if (b->cname->name_type == KRB5_NT_ENTERPRISE_PRINCIPAL) { if (b->cname->name_string.len != 1) { kdc_log(context, config, 0, "AS-REQ malformed canon request from %s, " "enterprise name with %d name components", from, b->cname->name_string.len); ret = KRB5_PARSE_MALFORMED; goto out; } ret = krb5_parse_name(context, b->cname->name_string.val[0], &client_princ); if (ret) goto out; } else { ret = _krb5_principalname2krb5_principal (context, &client_princ, *(b->cname), b->realm); if (ret) goto out; } ret = krb5_unparse_name(context, client_princ, &client_name); } if (ret) { kdc_log(context, config, 0, "AS-REQ malformed client name from %s", from); goto out; } kdc_log(context, config, 0, "AS-REQ %s from %s for %s", client_name, from, server_name); ret = _kdc_db_fetch(context, config, client_princ, HDB_F_GET_CLIENT | flags, NULL, &client); if(ret){ kdc_log(context, config, 0, "UNKNOWN -- %s: %s", client_name, krb5_get_err_text(context, ret)); ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN; goto out; } ret = _kdc_db_fetch(context, config, server_princ, HDB_F_GET_SERVER|HDB_F_GET_KRBTGT, NULL, &server); if(ret){ kdc_log(context, config, 0, "UNKNOWN -- %s: %s", server_name, krb5_get_err_text(context, ret)); ret = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN; goto out; } ret = _kdc_windc_client_access(context, client, req); if(ret) goto out; ret = _kdc_check_flags(context, config, client, client_name, server, server_name, TRUE); if(ret) goto out; memset(&et, 0, sizeof(et)); memset(&ek, 0, sizeof(ek)); if(req->padata){ int i; const PA_DATA *pa; int found_pa = 0; log_patypes(context, config, req->padata); #ifdef PKINIT kdc_log(context, config, 5, "Looking for PKINIT pa-data -- %s", client_name); e_text = "No PKINIT PA found"; i = 0; if ((pa = _kdc_find_padata(req, &i, KRB5_PADATA_PK_AS_REQ))) ; if (pa == NULL) { i = 0; if((pa = _kdc_find_padata(req, &i, KRB5_PADATA_PK_AS_REQ_WIN))) ; } if (pa) { char *client_cert = NULL; ret = _kdc_pk_rd_padata(context, config, req, pa, &pkp); if (ret) { ret = KRB5KRB_AP_ERR_BAD_INTEGRITY; kdc_log(context, config, 5, "Failed to decode PKINIT PA-DATA -- %s", client_name); goto ts_enc; } if (ret == 0 && pkp == NULL) goto ts_enc; ret = _kdc_pk_check_client(context, config, client, pkp, &client_cert); if (ret) { e_text = "PKINIT certificate not allowed to " "impersonate principal"; _kdc_pk_free_client_param(context, pkp); kdc_log(context, config, 0, "%s", e_text); pkp = NULL; goto out; } found_pa = 1; et.flags.pre_authent = 1; kdc_log(context, config, 0, "PKINIT pre-authentication succeeded -- %s using %s", client_name, client_cert); free(client_cert); if (pkp) goto preauth_done; } ts_enc: #endif kdc_log(context, config, 5, "Looking for ENC-TS pa-data -- %s", client_name); i = 0; e_text = "No ENC-TS found"; while((pa = _kdc_find_padata(req, &i, KRB5_PADATA_ENC_TIMESTAMP))){ krb5_data ts_data; PA_ENC_TS_ENC p; size_t len; EncryptedData enc_data; Key *pa_key; char *str; found_pa = 1; ret = decode_EncryptedData(pa->padata_value.data, pa->padata_value.length, &enc_data, &len); if (ret) { ret = KRB5KRB_AP_ERR_BAD_INTEGRITY; kdc_log(context, config, 5, "Failed to decode PA-DATA -- %s", client_name); goto out; } ret = hdb_enctype2key(context, &client->entry, enc_data.etype, &pa_key); if(ret){ char *estr; e_text = "No key matches pa-data"; ret = KRB5KDC_ERR_ETYPE_NOSUPP; if(krb5_enctype_to_string(context, enc_data.etype, &estr)) estr = NULL; if(estr == NULL) kdc_log(context, config, 5, "No client key matching pa-data (%d) -- %s", enc_data.etype, client_name); else kdc_log(context, config, 5, "No client key matching pa-data (%s) -- %s", estr, client_name); free(estr); free_EncryptedData(&enc_data); continue; } try_next_key: ret = krb5_crypto_init(context, &pa_key->key, 0, &crypto); if (ret) { kdc_log(context, config, 0, "krb5_crypto_init failed: %s", krb5_get_err_text(context, ret)); free_EncryptedData(&enc_data); continue; } ret = krb5_decrypt_EncryptedData (context, crypto, KRB5_KU_PA_ENC_TIMESTAMP, &enc_data, &ts_data); krb5_crypto_destroy(context, crypto); if(ret){ krb5_error_code ret2; ret2 = krb5_enctype_to_string(context, pa_key->key.keytype, &str); if (ret2) str = NULL; kdc_log(context, config, 5, "Failed to decrypt PA-DATA -- %s " "(enctype %s) error %s", client_name, str ? str : "unknown enctype", krb5_get_err_text(context, ret)); free(str); if(hdb_next_enctype2key(context, &client->entry, enc_data.etype, &pa_key) == 0) goto try_next_key; e_text = "Failed to decrypt PA-DATA"; free_EncryptedData(&enc_data); ret = KRB5KDC_ERR_PREAUTH_FAILED; continue; } free_EncryptedData(&enc_data); ret = decode_PA_ENC_TS_ENC(ts_data.data, ts_data.length, &p, &len); krb5_data_free(&ts_data); if(ret){ e_text = "Failed to decode PA-ENC-TS-ENC"; ret = KRB5KDC_ERR_PREAUTH_FAILED; kdc_log(context, config, 5, "Failed to decode PA-ENC-TS_ENC -- %s", client_name); continue; } free_PA_ENC_TS_ENC(&p); if (abs(kdc_time - p.patimestamp) > context->max_skew) { char client_time[100]; krb5_format_time(context, p.patimestamp, client_time, sizeof(client_time), TRUE); ret = KRB5KRB_AP_ERR_SKEW; kdc_log(context, config, 0, "Too large time skew, " "client time %s is out by %u > %u seconds -- %s", client_time, (unsigned)abs(kdc_time - p.patimestamp), context->max_skew, client_name); #if 0 /* This code is from samba, needs testing */ /* * the following is needed to make windows clients * to retry using the timestamp in the error message * * this is maybe a bug in windows to not trying when e_text * is present... */ e_text = NULL; #else e_text = "Too large time skew"; #endif goto out; } et.flags.pre_authent = 1; ret = krb5_enctype_to_string(context,pa_key->key.keytype, &str); if (ret) str = NULL; kdc_log(context, config, 2, "ENC-TS Pre-authentication succeeded -- %s using %s", client_name, str ? str : "unknown enctype"); free(str); break; } #ifdef PKINIT preauth_done: #endif if(found_pa == 0 && config->require_preauth) goto use_pa; /* We come here if we found a pa-enc-timestamp, but if there was some problem with it, other than too large skew */ if(found_pa && et.flags.pre_authent == 0){ kdc_log(context, config, 0, "%s -- %s", e_text, client_name); e_text = NULL; goto out; } }else if (config->require_preauth || client->entry.flags.require_preauth || server->entry.flags.require_preauth) { METHOD_DATA method_data; PA_DATA *pa; unsigned char *buf; size_t len; use_pa: method_data.len = 0; method_data.val = NULL; ret = realloc_method_data(&method_data); pa = &method_data.val[method_data.len-1]; pa->padata_type = KRB5_PADATA_ENC_TIMESTAMP; pa->padata_value.length = 0; pa->padata_value.data = NULL; #ifdef PKINIT ret = realloc_method_data(&method_data); pa = &method_data.val[method_data.len-1]; pa->padata_type = KRB5_PADATA_PK_AS_REQ; pa->padata_value.length = 0; pa->padata_value.data = NULL; ret = realloc_method_data(&method_data); pa = &method_data.val[method_data.len-1]; pa->padata_type = KRB5_PADATA_PK_AS_REQ_WIN; pa->padata_value.length = 0; pa->padata_value.data = NULL; #endif /* * RFC4120 requires: * - If the client only knows about old enctypes, then send * both info replies (we send 'info' first in the list). * - If the client is 'modern', because it knows about 'new' * enctype types, then only send the 'info2' reply. */ /* XXX check ret */ if (only_older_enctype_p(req)) ret = get_pa_etype_info(context, config, &method_data, &client->entry, b->etype.val, b->etype.len); /* XXX check ret */ ret = get_pa_etype_info2(context, config, &method_data, &client->entry, b->etype.val, b->etype.len); ASN1_MALLOC_ENCODE(METHOD_DATA, buf, len, &method_data, &len, ret); free_METHOD_DATA(&method_data); e_data.data = buf; e_data.length = len; e_text ="Need to use PA-ENC-TIMESTAMP/PA-PK-AS-REQ", ret = KRB5KDC_ERR_PREAUTH_REQUIRED; kdc_log(context, config, 0, "No preauth found, returning PREAUTH-REQUIRED -- %s", client_name); goto out; } /* * Find the client key (for preauth ENC-TS verification and reply * encryption). Then the best encryption type for the KDC and * last the best session key that shared between the client and * KDC runtime enctypes. */ ret = _kdc_find_etype(context, client, b->etype.val, b->etype.len, &ckey, &cetype); if (ret) { kdc_log(context, config, 0, "Client (%s) has no support for etypes", client_name); goto out; } ret = _kdc_get_preferred_key(context, config, server, server_name, &setype, &skey); if(ret) goto out; /* * Select a session enctype from the list of the crypto systems * supported enctype, is supported by the client and is one of the * enctype of the enctype of the krbtgt. * * The later is used as a hint what enctype all KDC are supporting * to make sure a newer version of KDC wont generate a session * enctype that and older version of a KDC in the same realm can't * decrypt. * * But if the KDC admin is paranoid and doesn't want to have "no * the best" enctypes on the krbtgt, lets save the best pick from * the client list and hope that that will work for any other * KDCs. */ { const krb5_enctype *p; krb5_enctype clientbest = ETYPE_NULL; int i, j; p = krb5_kerberos_enctypes(context); sessionetype = ETYPE_NULL; for (i = 0; p[i] != ETYPE_NULL && sessionetype == ETYPE_NULL; i++) { if (krb5_enctype_valid(context, p[i]) != 0) continue; for (j = 0; j < b->etype.len && sessionetype == ETYPE_NULL; j++) { Key *dummy; /* check with client */ if (p[i] != b->etype.val[j]) continue; /* save best of union of { client, crypto system } */ if (clientbest == ETYPE_NULL) clientbest = p[i]; /* check with krbtgt */ ret = hdb_enctype2key(context, &server->entry, p[i], &dummy); if (ret) continue; sessionetype = p[i]; } } /* if krbtgt had no shared keys with client, pick clients best */ if (clientbest != ETYPE_NULL && sessionetype == ETYPE_NULL) { sessionetype = clientbest; } else if (sessionetype == ETYPE_NULL) { kdc_log(context, config, 0, "Client (%s) from %s has no common enctypes with KDC" "to use for the session key", client_name, from); goto out; } } log_as_req(context, config, cetype, setype, b); if(f.renew || f.validate || f.proxy || f.forwarded || f.enc_tkt_in_skey || (f.request_anonymous && !config->allow_anonymous)) { ret = KRB5KDC_ERR_BADOPTION; kdc_log(context, config, 0, "Bad KDC options -- %s", client_name); goto out; } rep.pvno = 5; rep.msg_type = krb_as_rep; copy_Realm(&client->entry.principal->realm, &rep.crealm); if (f.request_anonymous) _kdc_make_anonymous_principalname (&rep.cname); else _krb5_principal2principalname(&rep.cname, client->entry.principal); rep.ticket.tkt_vno = 5; copy_Realm(&server->entry.principal->realm, &rep.ticket.realm); _krb5_principal2principalname(&rep.ticket.sname, server->entry.principal); /* java 1.6 expects the name to be the same type, lets allow that * uncomplicated name-types. */ #define CNT(sp,t) (((sp)->sname->name_type) == KRB5_NT_##t) if (CNT(b, UNKNOWN) || CNT(b, PRINCIPAL) || CNT(b, SRV_INST) || CNT(b, SRV_HST) || CNT(b, SRV_XHST)) rep.ticket.sname.name_type = b->sname->name_type; #undef CNT et.flags.initial = 1; if(client->entry.flags.forwardable && server->entry.flags.forwardable) et.flags.forwardable = f.forwardable; else if (f.forwardable) { ret = KRB5KDC_ERR_POLICY; kdc_log(context, config, 0, "Ticket may not be forwardable -- %s", client_name); goto out; } if(client->entry.flags.proxiable && server->entry.flags.proxiable) et.flags.proxiable = f.proxiable; else if (f.proxiable) { ret = KRB5KDC_ERR_POLICY; kdc_log(context, config, 0, "Ticket may not be proxiable -- %s", client_name); goto out; } if(client->entry.flags.postdate && server->entry.flags.postdate) et.flags.may_postdate = f.allow_postdate; else if (f.allow_postdate){ ret = KRB5KDC_ERR_POLICY; kdc_log(context, config, 0, "Ticket may not be postdatable -- %s", client_name); goto out; } /* check for valid set of addresses */ if(!_kdc_check_addresses(context, config, b->addresses, from_addr)) { ret = KRB5KRB_AP_ERR_BADADDR; kdc_log(context, config, 0, "Bad address list requested -- %s", client_name); goto out; } ret = krb5_generate_random_keyblock(context, sessionetype, &et.key); if (ret) goto out; copy_PrincipalName(&rep.cname, &et.cname); copy_Realm(&rep.crealm, &et.crealm); { time_t start; time_t t; start = et.authtime = kdc_time; if(f.postdated && req->req_body.from){ ALLOC(et.starttime); start = *et.starttime = *req->req_body.from; et.flags.invalid = 1; et.flags.postdated = 1; /* XXX ??? */ } _kdc_fix_time(&b->till); t = *b->till; /* be careful not overflowing */ if(client->entry.max_life) t = start + min(t - start, *client->entry.max_life); if(server->entry.max_life) t = start + min(t - start, *server->entry.max_life); #if 0 t = min(t, start + realm->max_life); #endif et.endtime = t; if(f.renewable_ok && et.endtime < *b->till){ f.renewable = 1; if(b->rtime == NULL){ ALLOC(b->rtime); *b->rtime = 0; } if(*b->rtime < *b->till) *b->rtime = *b->till; } if(f.renewable && b->rtime){ t = *b->rtime; if(t == 0) t = MAX_TIME; if(client->entry.max_renew) t = start + min(t - start, *client->entry.max_renew); if(server->entry.max_renew) t = start + min(t - start, *server->entry.max_renew); #if 0 t = min(t, start + realm->max_renew); #endif ALLOC(et.renew_till); *et.renew_till = t; et.flags.renewable = 1; } } if (f.request_anonymous) et.flags.anonymous = 1; if(b->addresses){ ALLOC(et.caddr); copy_HostAddresses(b->addresses, et.caddr); } et.transited.tr_type = DOMAIN_X500_COMPRESS; krb5_data_zero(&et.transited.contents); copy_EncryptionKey(&et.key, &ek.key); /* The MIT ASN.1 library (obviously) doesn't tell lengths encoded * as 0 and as 0x80 (meaning indefinite length) apart, and is thus * incapable of correctly decoding SEQUENCE OF's of zero length. * * To fix this, always send at least one no-op last_req * * If there's a pw_end or valid_end we will use that, * otherwise just a dummy lr. */ ek.last_req.val = malloc(2 * sizeof(*ek.last_req.val)); if (ek.last_req.val == NULL) { ret = ENOMEM; goto out; } ek.last_req.len = 0; if (client->entry.pw_end && (config->kdc_warn_pwexpire == 0 || kdc_time + config->kdc_warn_pwexpire >= *client->entry.pw_end)) { ek.last_req.val[ek.last_req.len].lr_type = LR_PW_EXPTIME; ek.last_req.val[ek.last_req.len].lr_value = *client->entry.pw_end; ++ek.last_req.len; } if (client->entry.valid_end) { ek.last_req.val[ek.last_req.len].lr_type = LR_ACCT_EXPTIME; ek.last_req.val[ek.last_req.len].lr_value = *client->entry.valid_end; ++ek.last_req.len; } if (ek.last_req.len == 0) { ek.last_req.val[ek.last_req.len].lr_type = LR_NONE; ek.last_req.val[ek.last_req.len].lr_value = 0; ++ek.last_req.len; } ek.nonce = b->nonce; if (client->entry.valid_end || client->entry.pw_end) { ALLOC(ek.key_expiration); if (client->entry.valid_end) { if (client->entry.pw_end) *ek.key_expiration = min(*client->entry.valid_end, *client->entry.pw_end); else *ek.key_expiration = *client->entry.valid_end; } else *ek.key_expiration = *client->entry.pw_end; } else ek.key_expiration = NULL; ek.flags = et.flags; ek.authtime = et.authtime; if (et.starttime) { ALLOC(ek.starttime); *ek.starttime = *et.starttime; } ek.endtime = et.endtime; if (et.renew_till) { ALLOC(ek.renew_till); *ek.renew_till = *et.renew_till; } copy_Realm(&rep.ticket.realm, &ek.srealm); copy_PrincipalName(&rep.ticket.sname, &ek.sname); if(et.caddr){ ALLOC(ek.caddr); copy_HostAddresses(et.caddr, ek.caddr); } ALLOC(rep.padata); rep.padata->len = 0; rep.padata->val = NULL; reply_key = &ckey->key; #if PKINIT if (pkp) { ret = _kdc_pk_mk_pa_reply(context, config, pkp, client, req, req_buffer, &reply_key, rep.padata); if (ret) goto out; ret = _kdc_add_inital_verified_cas(context, config, pkp, &et); if (ret) goto out; } #endif set_salt_padata (rep.padata, ckey->salt); /* Add signing of alias referral */ if (f.canonicalize) { PA_ClientCanonicalized canon; krb5_data data; PA_DATA pa; krb5_crypto crypto; size_t len; memset(&canon, 0, sizeof(canon)); canon.names.requested_name = *b->cname; canon.names.real_name = client->entry.principal->name; ASN1_MALLOC_ENCODE(PA_ClientCanonicalizedNames, data.data, data.length, &canon.names, &len, ret); if (ret) goto out; if (data.length != len) krb5_abortx(context, "internal asn.1 error"); /* sign using "returned session key" */ ret = krb5_crypto_init(context, &et.key, 0, &crypto); if (ret) { free(data.data); goto out; } ret = krb5_create_checksum(context, crypto, KRB5_KU_CANONICALIZED_NAMES, 0, data.data, data.length, &canon.canon_checksum); free(data.data); krb5_crypto_destroy(context, crypto); if (ret) goto out; ASN1_MALLOC_ENCODE(PA_ClientCanonicalized, data.data, data.length, &canon, &len, ret); free_Checksum(&canon.canon_checksum); if (ret) goto out; if (data.length != len) krb5_abortx(context, "internal asn.1 error"); pa.padata_type = KRB5_PADATA_CLIENT_CANONICALIZED; pa.padata_value = data; ret = add_METHOD_DATA(rep.padata, &pa); free(data.data); if (ret) goto out; } if (rep.padata->len == 0) { free(rep.padata); rep.padata = NULL; } /* Add the PAC */ if (send_pac_p(context, req)) { krb5_pac p = NULL; krb5_data data; ret = _kdc_pac_generate(context, client, &p); if (ret) { kdc_log(context, config, 0, "PAC generation failed for -- %s", client_name); goto out; } if (p != NULL) { ret = _krb5_pac_sign(context, p, et.authtime, client->entry.principal, &skey->key, /* Server key */ &skey->key, /* FIXME: should be krbtgt key */ &data); krb5_pac_free(context, p); if (ret) { kdc_log(context, config, 0, "PAC signing failed for -- %s", client_name); goto out; } ret = _kdc_tkt_add_if_relevant_ad(context, &et, KRB5_AUTHDATA_WIN2K_PAC, &data); krb5_data_free(&data); if (ret) goto out; } } _kdc_log_timestamp(context, config, "AS-REQ", et.authtime, et.starttime, et.endtime, et.renew_till); /* do this as the last thing since this signs the EncTicketPart */ ret = _kdc_add_KRB5SignedPath(context, config, server, setype, NULL, NULL, &et); if (ret) goto out; ret = _kdc_encode_reply(context, config, &rep, &et, &ek, setype, server->entry.kvno, &skey->key, client->entry.kvno, reply_key, &e_text, reply); free_EncTicketPart(&et); free_EncKDCRepPart(&ek); if (ret) goto out; /* */ if (datagram_reply && reply->length > config->max_datagram_reply_length) { krb5_data_free(reply); ret = KRB5KRB_ERR_RESPONSE_TOO_BIG; e_text = "Reply packet too large"; } out: free_AS_REP(&rep); if(ret){ krb5_mk_error(context, ret, e_text, (e_data.data ? &e_data : NULL), client_princ, server_princ, NULL, NULL, reply); ret = 0; } #ifdef PKINIT if (pkp) _kdc_pk_free_client_param(context, pkp); #endif if (e_data.data) free(e_data.data); if (client_princ) krb5_free_principal(context, client_princ); free(client_name); if (server_princ) krb5_free_principal(context, server_princ); free(server_name); if(client) _kdc_free_ent(context, client); if(server) _kdc_free_ent(context, server); return ret; }