diff options
Diffstat (limited to 'crypto/heimdal/lib/krb5/rd_req.c')
-rw-r--r-- | crypto/heimdal/lib/krb5/rd_req.c | 441 |
1 files changed, 441 insertions, 0 deletions
diff --git a/crypto/heimdal/lib/krb5/rd_req.c b/crypto/heimdal/lib/krb5/rd_req.c new file mode 100644 index 0000000..9f8df1d --- /dev/null +++ b/crypto/heimdal/lib/krb5/rd_req.c @@ -0,0 +1,441 @@ +/* + * Copyright (c) 1997, 1998, 1999 Kungliga Tekniska Högskolan + * (Royal Institute of Technology, Stockholm, Sweden). + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * 3. Neither the name of the Institute nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <krb5_locl.h> + +RCSID("$Id: rd_req.c,v 1.38 1999/12/02 17:05:12 joda Exp $"); + +static krb5_error_code +decrypt_tkt_enc_part (krb5_context context, + krb5_keyblock *key, + EncryptedData *enc_part, + EncTicketPart *decr_part) +{ + krb5_error_code ret; + krb5_data plain; + size_t len; + krb5_crypto crypto; + + krb5_crypto_init(context, key, 0, &crypto); + ret = krb5_decrypt_EncryptedData (context, + crypto, + KRB5_KU_TICKET, + enc_part, + &plain); + krb5_crypto_destroy(context, crypto); + if (ret) + return ret; + + ret = krb5_decode_EncTicketPart(context, plain.data, plain.length, + decr_part, &len); + krb5_data_free (&plain); + return ret; +} + +static krb5_error_code +decrypt_authenticator (krb5_context context, + EncryptionKey *key, + EncryptedData *enc_part, + Authenticator *authenticator) +{ + krb5_error_code ret; + krb5_data plain; + size_t len; + krb5_crypto crypto; + + krb5_crypto_init(context, key, 0, &crypto); + ret = krb5_decrypt_EncryptedData (context, + crypto, + KRB5_KU_AP_REQ_AUTH, + enc_part, + &plain); + krb5_crypto_destroy(context, crypto); + if (ret) + return ret; + + ret = krb5_decode_Authenticator(context, plain.data, plain.length, + authenticator, &len); + krb5_data_free (&plain); + return ret; +} + +krb5_error_code +krb5_decode_ap_req(krb5_context context, + const krb5_data *inbuf, + krb5_ap_req *ap_req) +{ + krb5_error_code ret; + size_t len; + ret = decode_AP_REQ(inbuf->data, inbuf->length, ap_req, &len); + if (ret) + return ret; + if (ap_req->pvno != 5){ + free_AP_REQ(ap_req); + return KRB5KRB_AP_ERR_BADVERSION; + } + if (ap_req->msg_type != krb_ap_req){ + free_AP_REQ(ap_req); + return KRB5KRB_AP_ERR_MSG_TYPE; + } + if (ap_req->ticket.tkt_vno != 5){ + free_AP_REQ(ap_req); + return KRB5KRB_AP_ERR_BADVERSION; + } + return 0; +} + +krb5_error_code +krb5_decrypt_ticket(krb5_context context, + Ticket *ticket, + krb5_keyblock *key, + EncTicketPart *out, + krb5_flags flags) +{ + EncTicketPart t; + krb5_error_code ret; + ret = decrypt_tkt_enc_part (context, key, &ticket->enc_part, &t); + if (ret) + return ret; + + { + int32_t now; + time_t start = t.authtime; + + krb5_timeofday (context, &now); + if(t.starttime) + start = *t.starttime; + if(start - now > context->max_skew + || (t.flags.invalid + && !(flags & KRB5_VERIFY_AP_REQ_IGNORE_INVALID))) + return KRB5KRB_AP_ERR_TKT_NYV; + if(now - t.endtime > context->max_skew) + return KRB5KRB_AP_ERR_TKT_EXPIRED; + } + + if(out) + *out = t; + else + free_EncTicketPart(&t); + return 0; +} + +krb5_error_code +krb5_verify_authenticator_checksum(krb5_context context, + krb5_auth_context ac, + void *data, + size_t len) +{ + krb5_error_code ret; + krb5_keyblock *key; + krb5_authenticator authenticator; + krb5_crypto crypto; + + ret = krb5_auth_getauthenticator (context, + ac, + &authenticator); + if(ret) + return ret; + if(authenticator->cksum == NULL) + return -17; + ret = krb5_auth_con_getkey(context, ac, &key); + if(ret) { + krb5_free_authenticator(context, &authenticator); + return ret; + } + ret = krb5_crypto_init(context, key, 0, &crypto); + if(ret) + goto out; + ret = krb5_verify_checksum (context, + crypto, + KRB5_KU_AP_REQ_AUTH_CKSUM, + data, + len, + authenticator->cksum); + krb5_crypto_destroy(context, crypto); +out: + krb5_free_authenticator(context, &authenticator); + krb5_free_keyblock(context, key); + return ret; +} + +krb5_error_code +krb5_verify_ap_req(krb5_context context, + krb5_auth_context *auth_context, + krb5_ap_req *ap_req, + krb5_const_principal server, + krb5_keyblock *keyblock, + krb5_flags flags, + krb5_flags *ap_req_options, + krb5_ticket **ticket) +{ + krb5_ticket t; + krb5_auth_context ac; + krb5_error_code ret; + + if(auth_context){ + if(*auth_context == NULL){ + krb5_auth_con_init(context, &ac); + *auth_context = ac; + }else + ac = *auth_context; + }else + krb5_auth_con_init(context, &ac); + + if (ap_req->ap_options.use_session_key && ac->keyblock){ + ret = krb5_decrypt_ticket(context, &ap_req->ticket, + ac->keyblock, + &t.ticket, + flags); + krb5_free_keyblock(context, ac->keyblock); + ac->keyblock = NULL; + }else + ret = krb5_decrypt_ticket(context, &ap_req->ticket, + keyblock, + &t.ticket, + flags); + + if(ret) + return ret; + + principalname2krb5_principal(&t.server, ap_req->ticket.sname, + ap_req->ticket.realm); + principalname2krb5_principal(&t.client, t.ticket.cname, + t.ticket.crealm); + + /* save key */ + + krb5_copy_keyblock(context, &t.ticket.key, &ac->keyblock); + + ret = decrypt_authenticator (context, + &t.ticket.key, + &ap_req->authenticator, + ac->authenticator); + if (ret){ + /* XXX free data */ + return ret; + } + + { + krb5_principal p1, p2; + krb5_boolean res; + + principalname2krb5_principal(&p1, + ac->authenticator->cname, + ac->authenticator->crealm); + principalname2krb5_principal(&p2, + t.ticket.cname, + t.ticket.crealm); + res = krb5_principal_compare (context, p1, p2); + krb5_free_principal (context, p1); + krb5_free_principal (context, p2); + if (!res) + return KRB5KRB_AP_ERR_BADMATCH; + } + + /* check addresses */ + + if (t.ticket.caddr + && ac->remote_address + && !krb5_address_search (context, + ac->remote_address, + t.ticket.caddr)) + return KRB5KRB_AP_ERR_BADADDR; + + if (ac->authenticator->seq_number) + ac->remote_seqnumber = *ac->authenticator->seq_number; + + /* XXX - Xor sequence numbers */ + + /* XXX - subkeys? */ + /* And where should it be stored? */ + + if (ac->authenticator->subkey) { + krb5_copy_keyblock(context, + ac->authenticator->subkey, + &ac->remote_subkey); + } + + if (ap_req_options) { + *ap_req_options = 0; + if (ap_req->ap_options.use_session_key) + *ap_req_options |= AP_OPTS_USE_SESSION_KEY; + if (ap_req->ap_options.mutual_required) + *ap_req_options |= AP_OPTS_MUTUAL_REQUIRED; + } + + if(ticket){ + *ticket = malloc(sizeof(**ticket)); + **ticket = t; + } else + krb5_free_ticket (context, &t); + return 0; +} + + +krb5_error_code +krb5_rd_req_with_keyblock(krb5_context context, + krb5_auth_context *auth_context, + const krb5_data *inbuf, + krb5_const_principal server, + krb5_keyblock *keyblock, + krb5_flags *ap_req_options, + krb5_ticket **ticket) +{ + krb5_error_code ret; + krb5_ap_req ap_req; + + if (*auth_context == NULL) { + ret = krb5_auth_con_init(context, auth_context); + if (ret) + return ret; + } + + ret = krb5_decode_ap_req(context, inbuf, &ap_req); + if(ret) + return ret; + + ret = krb5_verify_ap_req(context, + auth_context, + &ap_req, + server, + keyblock, + 0, + ap_req_options, + ticket); + + free_AP_REQ(&ap_req); + return ret; +} + +static krb5_error_code +get_key_from_keytab(krb5_context context, + krb5_auth_context *auth_context, + krb5_ap_req *ap_req, + krb5_const_principal server, + krb5_keytab keytab, + krb5_keyblock **out) +{ + krb5_keytab_entry entry; + krb5_error_code ret; + int kvno; + krb5_keytab real_keytab; + + if(keytab == NULL) + krb5_kt_default(context, &real_keytab); + else + real_keytab = keytab; + + if (ap_req->ticket.enc_part.kvno) + kvno = *ap_req->ticket.enc_part.kvno; + else + kvno = 0; + + ret = krb5_kt_get_entry (context, + real_keytab, + server, + kvno, + ap_req->ticket.enc_part.etype, + &entry); + if(ret) + goto out; + ret = krb5_copy_keyblock(context, &entry.keyblock, out); + krb5_kt_free_entry (context, &entry); +out: + if(keytab == NULL) + krb5_kt_close(context, real_keytab); + + return ret; +} + +krb5_error_code +krb5_rd_req(krb5_context context, + krb5_auth_context *auth_context, + const krb5_data *inbuf, + krb5_const_principal server, + krb5_keytab keytab, + krb5_flags *ap_req_options, + krb5_ticket **ticket) +{ + krb5_error_code ret; + krb5_ap_req ap_req; + krb5_keyblock *keyblock = NULL; + krb5_principal service = NULL; + + if (*auth_context == NULL) { + ret = krb5_auth_con_init(context, auth_context); + if (ret) + return ret; + } + + ret = krb5_decode_ap_req(context, inbuf, &ap_req); + if(ret) + return ret; + + if(server == NULL){ + principalname2krb5_principal(&service, + ap_req.ticket.sname, + ap_req.ticket.realm); + server = service; + } + + if(ap_req.ap_options.use_session_key == 0 || + (*auth_context)->keyblock == NULL){ + ret = get_key_from_keytab(context, + auth_context, + &ap_req, + server, + keytab, + &keyblock); + if(ret) + goto out; + } + + + ret = krb5_verify_ap_req(context, + auth_context, + &ap_req, + server, + keyblock, + 0, + ap_req_options, + ticket); + + if(keyblock != NULL) + krb5_free_keyblock(context, keyblock); + +out: + free_AP_REQ(&ap_req); + if(service) + krb5_free_principal(context, service); + return ret; +} |