crypto/dist/heimdal/lib/krb5/build_auth.c

   1 /*
   2  * Copyright (c) 1997 - 2003 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include <krb5_locl.h>
  35
  36 __RCSID("$Heimdal: build_auth.c 17033 2006-04-10 08:53:21Z lha $"
  37         "$NetBSD$");
  38
  39 static krb5_error_code
  40 make_etypelist(krb5_context context,
  41                krb5_authdata **auth_data)
  42 {
  43     EtypeList etypes;
  44     krb5_error_code ret;
  45     krb5_authdata ad;
  46     u_char *buf;
  47     size_t len;
  48     size_t buf_size;
  49
  50     ret = krb5_init_etype(context, &etypes.len, &etypes.val, NULL);
  51     if (ret)
  52         return ret;
  53
  54     ASN1_MALLOC_ENCODE(EtypeList, buf, buf_size, &etypes, &len, ret);
  55     if (ret) {
  56         free_EtypeList(&etypes);
  57         return ret;
  58     }
  59     if(buf_size != len)
  60         krb5_abortx(context, "internal error in ASN.1 encoder");
  61     free_EtypeList(&etypes);
  62
  63     ALLOC_SEQ(&ad, 1);
  64     if (ad.val == NULL) {
  65         free(buf);
  66         krb5_set_error_string(context, "malloc: out of memory");
  67         return ENOMEM;
  68     }
  69
  70     ad.val[0].ad_type = KRB5_AUTHDATA_GSS_API_ETYPE_NEGOTIATION;
  71     ad.val[0].ad_data.length = len;
  72     ad.val[0].ad_data.data = buf;
  73
  74     ASN1_MALLOC_ENCODE(AD_IF_RELEVANT, buf, buf_size, &ad, &len, ret);
  75     if (ret) {
  76         free_AuthorizationData(&ad);
  77         return ret;
  78     }
  79     if(buf_size != len)
  80         krb5_abortx(context, "internal error in ASN.1 encoder");
  81     free_AuthorizationData(&ad);
  82
  83     ALLOC(*auth_data, 1);
  84     if (*auth_data == NULL) {
  85         krb5_set_error_string(context, "malloc: out of memory");
  86         return ENOMEM;
  87     }
  88
  89     ALLOC_SEQ(*auth_data, 1);
  90     if ((*auth_data)->val == NULL) {
  91         free(buf);
  92         krb5_set_error_string(context, "malloc: out of memory");
  93         return ENOMEM;
  94     }
  95
  96     (*auth_data)->val[0].ad_type = KRB5_AUTHDATA_IF_RELEVANT;
  97     (*auth_data)->val[0].ad_data.length = len;
  98     (*auth_data)->val[0].ad_data.data = buf;
  99
 100     return 0;
 101 }
 102
 103 krb5_error_code KRB5_LIB_FUNCTION
 104 krb5_build_authenticator (krb5_context context,
 105                           krb5_auth_context auth_context,
 106                           krb5_enctype enctype,
 107                           krb5_creds *cred,
 108                           Checksum *cksum,
 109                           Authenticator **auth_result,
 110                           krb5_data *result,
 111                           krb5_key_usage usage)
 112 {
 113     Authenticator *auth;
 114     u_char *buf = NULL;
 115     size_t buf_size;
 116     size_t len;
 117     krb5_error_code ret;
 118     krb5_crypto crypto;
 119
 120     auth = calloc(1, sizeof(*auth));
 121     if (auth == NULL) {
 122         krb5_set_error_string(context, "malloc: out of memory");
 123         return ENOMEM;
 124     }
 125
 126     auth->authenticator_vno = 5;
 127     copy_Realm(&cred->client->realm, &auth->crealm);
 128     copy_PrincipalName(&cred->client->name, &auth->cname);
 129
 130     krb5_us_timeofday (context, &auth->ctime, &auth->cusec);
 131
 132     ret = krb5_auth_con_getlocalsubkey(context, auth_context, &auth->subkey);
 133     if(ret)
 134         goto fail;
 135
 136     if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) {
 137         if(auth_context->local_seqnumber == 0)
 138             krb5_generate_seq_number (context,
 139                                       &cred->session,
 140                                       &auth_context->local_seqnumber);
 141         ALLOC(auth->seq_number, 1);
 142         if(auth->seq_number == NULL) {
 143             ret = ENOMEM;
 144             goto fail;
 145         }
 146         *auth->seq_number = auth_context->local_seqnumber;
 147     } else
 148         auth->seq_number = NULL;
 149     auth->authorization_data = NULL;
 150     auth->cksum = cksum;
 151
 152     if (cksum != NULL && cksum->cksumtype == CKSUMTYPE_GSSAPI) {
 153         /*
 154          * This is not GSS-API specific, we only enable it for
 155          * GSS for now
 156          */
 157         ret = make_etypelist(context, &auth->authorization_data);
 158         if (ret)
 159             goto fail;
 160     }
 161
 162     /* XXX - Copy more to auth_context? */
 163
 164     auth_context->authenticator->ctime = auth->ctime;
 165     auth_context->authenticator->cusec = auth->cusec;
 166
 167     ASN1_MALLOC_ENCODE(Authenticator, buf, buf_size, auth, &len, ret);
 168     if (ret)
 169         goto fail;
 170     if(buf_size != len)
 171         krb5_abortx(context, "internal error in ASN.1 encoder");
 172
 173     ret = krb5_crypto_init(context, &cred->session, enctype, &crypto);
 174     if (ret)
 175         goto fail;
 176     ret = krb5_encrypt (context,
 177                         crypto,
 178                         usage /* KRB5_KU_AP_REQ_AUTH */,
 179                         buf + buf_size - len,
 180                         len,
 181                         result);
 182     krb5_crypto_destroy(context, crypto);
 183
 184     if (ret)
 185         goto fail;
 186
 187     free (buf);
 188
 189     if (auth_result)
 190         *auth_result = auth;
 191     else {
 192         /* Don't free the `cksum', it's allocated by the caller */
 193         auth->cksum = NULL;
 194         free_Authenticator (auth);
 195         free (auth);
 196     }
 197     return ret;
 198   fail:
 199     free_Authenticator (auth);
 200     free (auth);
 201     free (buf);
 202     return ret;
 203 }