/* $KTH: mk_req.c,v 1.17 1997/05/30 17:42:38 bg Exp $ */ /* * Copyright (c) 1995, 1996, 1997 Kungliga Tekniska Högskolan * (Royal Institute of Technology, Stockholm, Sweden). * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the Kungliga Tekniska * Högskolan and its contributors. * * 4. Neither the name of the Institute nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include "krb_locl.h" static int lifetime = 255; /* But no longer than TGT says. */ static void build_request(KTEXT req, char *name, char *inst, char *realm, u_int32_t checksum) { struct timeval tv; unsigned char *p = req->dat; p += krb_put_nir(name, inst, realm, p); p += krb_put_int(checksum, p, 4); /* Fill in the times on the request id */ gettimeofday(&tv, NULL); *p++ = tv.tv_usec / 5000; /* 5ms */ p += krb_put_int(tv.tv_sec, p, 4); /* Fill to a multiple of 8 bytes for DES */ req->length = ((p - req->dat + 7)/8) * 8; } /* * krb_mk_req takes a text structure in which an authenticator is to * be built, the name of a service, an instance, a realm, * and a checksum. It then retrieves a ticket for * the desired service and creates an authenticator in the text * structure passed as the first argument. krb_mk_req returns * KSUCCESS on success and a Kerberos error code on failure. * * The peer procedure on the other end is krb_rd_req. When making * any changes to this routine it is important to make corresponding * changes to krb_rd_req. * * The authenticator consists of the following: * * authent->dat * * unsigned char KRB_PROT_VERSION protocol version no. * unsigned char AUTH_MSG_APPL_REQUEST message type * (least significant * bit of above) HOST_BYTE_ORDER local byte ordering * unsigned char kvno from ticket server's key version * string realm server's realm * unsigned char tl ticket length * unsigned char idl request id length * text ticket->dat ticket for server * text req_id->dat request id * * The ticket information is retrieved from the ticket cache or * fetched from Kerberos. The request id (called the "authenticator" * in the papers on Kerberos) contains the following: * * req_id->dat * * string cr.pname {name, instance, and * string cr.pinst realm of principal * string myrealm making this request} * 4 bytes checksum checksum argument given * unsigned char tv_local.tf_usec time (milliseconds) * 4 bytes tv_local.tv_sec time (seconds) * * req_id->length = 3 strings + 3 terminating nulls + 5 bytes for time, * all rounded up to multiple of 8. */ int krb_mk_req(KTEXT authent, char *service, char *instance, char *realm, int32_t checksum) { KTEXT_ST req_st; KTEXT req_id = &req_st; CREDENTIALS cr; /* Credentials used by retr */ KTEXT ticket = &(cr.ticket_st); /* Pointer to tkt_st */ int retval; /* Returned by krb_get_cred */ char myrealm[REALM_SZ]; unsigned char *p = authent->dat; p += krb_put_int(KRB_PROT_VERSION, p, 1); p += krb_put_int(AUTH_MSG_APPL_REQUEST, p, 1); /* Get the ticket and move it into the authenticator */ if (krb_ap_req_debug) krb_warning("Realm: %s\n", realm); retval = krb_get_cred(service,instance,realm,&cr); if (retval == RET_NOTKT) { retval = get_ad_tkt(service, instance, realm, lifetime); if (retval == KSUCCESS) retval = krb_get_cred(service, instance, realm, &cr); } if (retval != KSUCCESS) return retval; /* * With multi realm ticket files either find a matching TGT or * else use the first TGT for inter-realm authentication. * * In myrealm hold the realm of the principal "owning" the * corresponding ticket-granting-ticket. */ retval = krb_get_cred(KRB_TICKET_GRANTING_TICKET, realm, realm, 0); if (retval == KSUCCESS) strncpy(myrealm, realm, REALM_SZ); else retval = krb_get_tf_realm(TKT_FILE, myrealm); if (retval != KSUCCESS) return retval; if (krb_ap_req_debug) krb_warning("serv=%s.%s@%s princ=%s.%s@%s\n", service, instance, realm, cr.pname, cr.pinst, myrealm); p += krb_put_int(cr.kvno, p, 1); p += krb_put_string(realm, p); p += krb_put_int(ticket->length, p, 1); build_request(req_id, cr.pname, cr.pinst, myrealm, checksum); encrypt_ktext(req_id, &cr.session, DES_ENCRYPT); p += krb_put_int(req_id->length, p, 1); memcpy(p, ticket->dat, ticket->length); p += ticket->length; memcpy(p, req_id->dat, req_id->length); p += req_id->length; authent->length = p - authent->dat; memset(&cr, 0, sizeof(cr)); memset(&req_st, 0, sizeof(req_st)); if (krb_ap_req_debug) krb_warning("Authent->length = %d\n", authent->length); return KSUCCESS; } /* * krb_set_lifetime sets the default lifetime for additional tickets * obtained via krb_mk_req(). * * It returns the previous value of the default lifetime. */ int krb_set_lifetime(int newval) { int olife = lifetime; lifetime = newval; return(olife); }