third_party/heimdal/lib/krb5/mk_cred.c

   1 /*
   2  * Copyright (c) 1997 - 2004 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 #define CHECKED_ALLOC(dst) do {                                 \
  37             if ((ALLOC(dst, 1)) == NULL) {                      \
  38                 ret = krb5_enomem(context);                     \
  39                 goto out;                                       \
  40             }                                                   \
  41         } while (0)
  42
  43 #define CHECKED_COPY(cp_func, dst, src) do {                    \
  44             if (cp_func(src, dst)) {                            \
  45                 ret = krb5_enomem(context);                     \
  46                 goto out;                                       \
  47             }                                                   \
  48         } while (0)
  49 #define CHECKED_COPY_PPC2KCI(cp_func, dst, src)                 \
  50         CHECKED_COPY(cp_func, krb_cred_info->dst, &ppcreds[i]->src)
  51
  52 #define CHECKED_ALLOC_ASSIGN(dst, src) do {                     \
  53             if ((ALLOC(dst, 1)) == NULL) {                      \
  54                 ret = krb5_enomem(context);                     \
  55                 goto out;                                       \
  56             } else                                              \
  57                 *dst = src;                                     \
  58         } while (0)
  59 #define CHECKED_ALLOC_ASSIGN_PPC2KCI(dst, src)                  \
  60         CHECKED_ALLOC_ASSIGN(krb_cred_info->dst, ppcreds[i]->src)
  61
  62 #define CHECKED_ALLOC_COPY(cp_func, dst, src) do {              \
  63             if ((ALLOC(dst, 1)) == NULL || cp_func(src, dst)) { \
  64                 ret = krb5_enomem(context);                     \
  65                 goto out;                                       \
  66             }                                                   \
  67         } while (0)
  68 #define CHECKED_ALLOC_COPY_PPC2KCI(cp_func, dst, src)           \
  69         CHECKED_ALLOC_COPY(cp_func, krb_cred_info->dst, &ppcreds[i]->src)
  70
  71 /**
  72  * Make a KRB-CRED PDU with N credentials.
  73  *
  74  * @param context A kerberos 5 context.
  75  * @param auth_context The auth context with the key to encrypt the out_data.
  76  * @param ppcreds A null-terminated array of credentials to forward.
  77  * @param ppdata The output KRB-CRED (to be freed by caller).
  78  * @param replay_data (unused).
  79  *
  80  * @return Return an error code or 0.
  81  *
  82  * @ingroup krb5_credential
  83  */
  84
  85 /* ARGSUSED */
  86 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
  87 krb5_mk_ncred(krb5_context context, krb5_auth_context auth_context,
  88               krb5_creds **ppcreds, krb5_data **ppdata,
  89               krb5_replay_data *replay_data)
  90 {
  91     krb5_error_code ret;
  92     krb5_data out_data;
  93
  94     ret = _krb5_mk_ncred(context, auth_context, ppcreds, &out_data,
  95         replay_data);
  96     if (ret == 0) {
  97         /*
  98          * MIT allocates the return structure for no good reason. We do
  99          * likewise as, in this case, incompatibility is the greater evil.
 100          */
 101         *ppdata = calloc(1, sizeof(**ppdata));
 102         if (*ppdata) {
 103             **ppdata = out_data;
 104         } else {
 105             krb5_data_free(&out_data);
 106             ret = krb5_enomem(context);
 107         }
 108     }
 109
 110     return ret;
 111 }
 112
 113 /* ARGSUSED */
 114 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 115 _krb5_mk_ncred(krb5_context context,
 116                krb5_auth_context auth_context,
 117                krb5_creds **ppcreds,
 118                krb5_data *out_data,
 119                krb5_replay_data *replay_data)
 120 {
 121     krb5_error_code ret;
 122     EncKrbCredPart enc_krb_cred_part;
 123     KrbCredInfo *krb_cred_info;
 124     krb5_crypto crypto;
 125     KRB_CRED cred;
 126     unsigned char *buf = NULL;
 127     size_t ncreds, i;
 128     size_t buf_size;
 129     size_t len;
 130
 131     /*
 132      * The ownership of 'buf' is re-assigned to a containing structure
 133      * multiple times. We enforce an invariant, either buf is non-zero
 134      * and we own it, or buf is zero and it is freed or some structure
 135      * owns any storage previously allocated as 'buf'.
 136      */
 137 #define CHOWN_BUF(x, buf) do { (x) = (buf); (buf) = 0; } while (0)
 138 #define DISOWN_BUF(buf) do { free(buf); (buf) = 0; } while (0)
 139
 140     for (ncreds = 0; ppcreds[ncreds]; ncreds++)
 141         ;
 142
 143     memset (&cred, 0, sizeof(cred));
 144     memset (&enc_krb_cred_part, 0, sizeof(enc_krb_cred_part));
 145     cred.pvno = 5;
 146     cred.msg_type = krb_cred;
 147     ALLOC_SEQ(&cred.tickets, ncreds);
 148     if (cred.tickets.val == NULL) {
 149         ret = krb5_enomem(context);
 150         goto out;
 151     }
 152     ALLOC_SEQ(&enc_krb_cred_part.ticket_info, ncreds);
 153     if (enc_krb_cred_part.ticket_info.val == NULL) {
 154         ret = krb5_enomem(context);
 155         goto out;
 156     }
 157
 158     for (i = 0; i < ncreds; i++) {
 159         ret = decode_Ticket(ppcreds[i]->ticket.data,
 160                             ppcreds[i]->ticket.length,
 161                             &cred.tickets.val[i],
 162                             &len);/* don't care about len */
 163         if (ret)
 164            goto out;
 165
 166         /* fill ticket_info.val[i] */
 167         krb_cred_info = &enc_krb_cred_part.ticket_info.val[i];
 168
 169         CHECKED_COPY(copy_EncryptionKey,
 170                      &krb_cred_info->key, &ppcreds[i]->session);
 171         CHECKED_ALLOC_COPY_PPC2KCI(copy_Realm, prealm, client->realm);
 172         CHECKED_ALLOC_COPY_PPC2KCI(copy_PrincipalName, pname, client->name);
 173         CHECKED_ALLOC_ASSIGN_PPC2KCI(flags, flags.b);
 174         CHECKED_ALLOC_ASSIGN_PPC2KCI(authtime, times.authtime);
 175         CHECKED_ALLOC_ASSIGN_PPC2KCI(starttime, times.starttime);
 176         CHECKED_ALLOC_ASSIGN_PPC2KCI(endtime, times.endtime);
 177         CHECKED_ALLOC_ASSIGN_PPC2KCI(renew_till, times.renew_till);
 178         CHECKED_ALLOC_COPY_PPC2KCI(copy_Realm, srealm, server->realm);
 179         CHECKED_ALLOC_COPY_PPC2KCI(copy_PrincipalName, sname, server->name);
 180         CHECKED_ALLOC_COPY_PPC2KCI(copy_HostAddresses, caddr, addresses);
 181     }
 182
 183     if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_TIME) {
 184         krb5_timestamp sec;
 185         int32_t usec;
 186
 187         krb5_us_timeofday (context, &sec, &usec);
 188
 189         CHECKED_ALLOC_ASSIGN(enc_krb_cred_part.timestamp, sec);
 190         CHECKED_ALLOC_ASSIGN(enc_krb_cred_part.usec, usec);
 191     } else {
 192         enc_krb_cred_part.timestamp = NULL;
 193         enc_krb_cred_part.usec = NULL;
 194         /* XXX Er, shouldn't we set the seq nums?? */
 195     }
 196
 197     /* XXX: Is this needed? */
 198     if (auth_context->local_address && auth_context->local_port) {
 199         ret = krb5_make_addrport(context,
 200                                  &enc_krb_cred_part.s_address,
 201                                  auth_context->local_address,
 202                                  auth_context->local_port);
 203         if (ret)
 204             goto out;
 205     }
 206
 207     /* XXX: Is this needed? */
 208     if (auth_context->remote_address) {
 209         if (auth_context->remote_port) {
 210             /*
 211              * XXX: Should we be checking "no-addresses" for
 212              * the receiving realm?
 213              */
 214             ret = krb5_make_addrport(context,
 215                                      &enc_krb_cred_part.r_address,
 216                                      auth_context->remote_address,
 217                                      auth_context->remote_port);
 218             if (ret)
 219                 goto out;
 220         } else {
 221             /*
 222              * XXX Ugly, make krb5_make_addrport() handle missing port
 223              * number (i.e., port == 0), then remove this else.
 224              */
 225             CHECKED_ALLOC(enc_krb_cred_part.r_address);
 226             ret = krb5_copy_address(context, auth_context->remote_address,
 227                                     enc_krb_cred_part.r_address);
 228             if (ret)
 229                 goto out;
 230         }
 231     }
 232
 233     /* encode EncKrbCredPart */
 234     ASN1_MALLOC_ENCODE(EncKrbCredPart, buf, buf_size,
 235                        &enc_krb_cred_part, &len, ret);
 236     if (ret)
 237         goto out;
 238
 239     /**
 240      * Some older of the MIT gssapi library used clear-text tickets
 241      * (warped inside AP-REQ encryption), use the krb5_auth_context
 242      * flag KRB5_AUTH_CONTEXT_CLEAR_FORWARDED_CRED to support those
 243      * tickets. The session key is used otherwise to encrypt the
 244      * forwarded ticket.
 245      */
 246
 247     if (auth_context->flags & KRB5_AUTH_CONTEXT_CLEAR_FORWARDED_CRED) {
 248         cred.enc_part.etype = KRB5_ENCTYPE_NULL;
 249         cred.enc_part.kvno = NULL;
 250         CHOWN_BUF(cred.enc_part.cipher.data, buf);
 251         cred.enc_part.cipher.length = buf_size;
 252     } else {
 253         /*
 254          * Here older versions then 0.7.2 of Heimdal used the local or
 255          * remote subkey. That is wrong, the session key should be
 256          * used. Heimdal 0.7.2 and newer have code to try both in the
 257          * receiving end.
 258          */
 259
 260         ret = krb5_crypto_init(context, auth_context->keyblock, 0, &crypto);
 261         if (ret == 0)
 262             ret = krb5_encrypt_EncryptedData(context,
 263                                              crypto,
 264                                              KRB5_KU_KRB_CRED,
 265                                              buf,
 266                                              len,
 267                                              0,
 268                                              &cred.enc_part);
 269         if (ret)
 270             goto out;
 271         DISOWN_BUF(buf);
 272         krb5_crypto_destroy(context, crypto);
 273     }
 274
 275     ASN1_MALLOC_ENCODE(KRB_CRED, buf, buf_size, &cred, &len, ret);
 276     if (ret)
 277         goto out;
 278
 279     CHOWN_BUF(out_data->data, buf);
 280     out_data->length = len;
 281     ret = 0;
 282
 283  out:
 284     free_EncKrbCredPart(&enc_krb_cred_part);
 285     free_KRB_CRED(&cred);
 286     free(buf);
 287     return ret;
 288 }
 289
 290 /**
 291  * Make a KRB-CRED PDU with 1 credential.
 292  *
 293  * @param context A kerberos 5 context.
 294  * @param auth_context The auth context with the key to encrypt the out_data.
 295  * @param ppcred A credential to forward.
 296  * @param ppdata The output KRB-CRED (to be freed by caller).
 297  * @param replay_data (unused).
 298  *
 299  * @return Return an error code or 0.
 300  *
 301  * @ingroup krb5_credential
 302  */
 303
 304 /* ARGSUSED */
 305 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 306 krb5_mk_1cred(krb5_context context, krb5_auth_context auth_context,
 307               krb5_creds *ppcred, krb5_data **ppdata,
 308               krb5_replay_data *replay_data)
 309 {
 310     krb5_creds *ppcreds[2] = { ppcred, NULL };
 311
 312     return krb5_mk_ncred(context, auth_context, ppcreds, ppdata, replay_data);
 313 }
 314
 315 /* ARGSUSED */
 316 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 317 _krb5_mk_1cred(krb5_context context, krb5_auth_context auth_context,
 318                krb5_creds *ppcred, krb5_data *ppdata,
 319                krb5_replay_data *replay_data)
 320 {
 321     krb5_creds *ppcreds[2] = { ppcred, NULL };
 322
 323     return _krb5_mk_ncred(context, auth_context, ppcreds, ppdata, replay_data);
 324 }