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mk_priv.c revision 1.1.1.1.20.1 
      1 /*	$NetBSD: mk_priv.c,v 1.1.1.1.20.1 2017/08/30 06:57:37 snj Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1997 - 2003 Kungliga Tekniska Hgskolan
      5  * (Royal Institute of Technology, Stockholm, Sweden).
      6  * All rights reserved.
      7  *
      8  * Redistribution and use in source and binary forms, with or without
      9  * modification, are permitted provided that the following conditions
     10  * are met:
     11  *
     12  * 1. Redistributions of source code must retain the above copyright
     13  *    notice, this list of conditions and the following disclaimer.
     14  *
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * 3. Neither the name of the Institute nor the names of its contributors
     20  *    may be used to endorse or promote products derived from this software
     21  *    without specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
     24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
     27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  */
     35 
     36 #include "krb5_locl.h"
     37 
     38 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
     39 krb5_mk_priv(krb5_context context,
     40 	     krb5_auth_context auth_context,
     41 	     const krb5_data *userdata,
     42 	     krb5_data *outbuf,
     43 	     krb5_replay_data *outdata)
     44 {
     45     krb5_error_code ret;
     46     KRB_PRIV s;
     47     EncKrbPrivPart part;
     48     u_char *buf = NULL;
     49     size_t buf_size;
     50     size_t len = 0;
     51     krb5_crypto crypto;
     52     krb5_keyblock *key;
     53     krb5_replay_data rdata;
     54 
     55     if ((auth_context->flags &
     56 	 (KRB5_AUTH_CONTEXT_RET_TIME | KRB5_AUTH_CONTEXT_RET_SEQUENCE)) &&
     57 	outdata == NULL)
     58 	return KRB5_RC_REQUIRED; /* XXX better error, MIT returns this */
     59 
     60     if (auth_context->local_subkey)
     61 	key = auth_context->local_subkey;
     62     else if (auth_context->remote_subkey)
     63 	key = auth_context->remote_subkey;
     64     else
     65 	key = auth_context->keyblock;
     66 
     67     memset(&rdata, 0, sizeof(rdata));
     68 
     69     part.user_data = *userdata;
     70 
     71     krb5_us_timeofday (context, &rdata.timestamp, &rdata.usec);
     72 
     73     if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_TIME) {
     74 	part.timestamp = &rdata.timestamp;
     75 	part.usec      = &rdata.usec;
     76     } else {
     77 	part.timestamp = NULL;
     78 	part.usec      = NULL;
     79     }
     80 
     81     if (auth_context->flags & KRB5_AUTH_CONTEXT_RET_TIME) {
     82 	outdata->timestamp = rdata.timestamp;
     83 	outdata->usec = rdata.usec;
     84     }
     85 
     86     if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) {
     87 	rdata.seq = auth_context->local_seqnumber;
     88 	part.seq_number = &rdata.seq;
     89     } else
     90 	part.seq_number = NULL;
     91 
     92     if (auth_context->flags & KRB5_AUTH_CONTEXT_RET_SEQUENCE)
     93 	outdata->seq = auth_context->local_seqnumber;
     94 
     95     part.s_address = auth_context->local_address;
     96     part.r_address = auth_context->remote_address;
     97 
     98     krb5_data_zero (&s.enc_part.cipher);
     99 
    100     ASN1_MALLOC_ENCODE(EncKrbPrivPart, buf, buf_size, &part, &len, ret);
    101     if (ret)
    102 	goto fail;
    103     if (buf_size != len)
    104 	krb5_abortx(context, "internal error in ASN.1 encoder");
    105 
    106     s.pvno = 5;
    107     s.msg_type = krb_priv;
    108     s.enc_part.etype = key->keytype;
    109     s.enc_part.kvno = NULL;
    110 
    111     ret = krb5_crypto_init(context, key, 0, &crypto);
    112     if (ret) {
    113 	free (buf);
    114 	return ret;
    115     }
    116     ret = krb5_encrypt (context,
    117 			crypto,
    118 			KRB5_KU_KRB_PRIV,
    119 			buf + buf_size - len,
    120 			len,
    121 			&s.enc_part.cipher);
    122     krb5_crypto_destroy(context, crypto);
    123     if (ret) {
    124 	free(buf);
    125 	return ret;
    126     }
    127     free(buf);
    128 
    129 
    130     ASN1_MALLOC_ENCODE(KRB_PRIV, buf, buf_size, &s, &len, ret);
    131     if (ret)
    132 	goto fail;
    133     if (buf_size != len)
    134 	krb5_abortx(context, "internal error in ASN.1 encoder");
    135 
    136     krb5_data_free (&s.enc_part.cipher);
    137 
    138     ret = krb5_data_copy(outbuf, buf + buf_size - len, len);
    139     if (ret) {
    140 	free(buf);
    141 	return krb5_enomem(context);
    142     }
    143     free (buf);
    144     if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE)
    145 	auth_context->local_seqnumber =
    146 	    (auth_context->local_seqnumber + 1) & 0xFFFFFFFF;
    147     return 0;
    148 
    149   fail:
    150     free (buf);
    151     krb5_data_free (&s.enc_part.cipher);
    152     return ret;
    153 }
    154