crypto/heimdal-0.6.3/lib/krb5/recvauth.c

   1 /*
   2  * Copyright (c) 1997-2002 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("$Id: recvauth.c,v 1.16 2002/04/18 09:41:33 joda Exp $");
  37
  38 /*
  39  * See `sendauth.c' for the format.
  40  */
  41
  42 static krb5_boolean
  43 match_exact(const void *data, const char *appl_version)
  44 {
  45     return strcmp(data, appl_version) == 0;
  46 }
  47
  48 krb5_error_code
  49 krb5_recvauth(krb5_context context,
  50               krb5_auth_context *auth_context,
  51               krb5_pointer p_fd,
  52               const char *appl_version,
  53               krb5_principal server,
  54               int32_t flags,
  55               krb5_keytab keytab,
  56               krb5_ticket **ticket)
  57 {
  58     return krb5_recvauth_match_version(context, auth_context, p_fd,
  59                                        match_exact, appl_version,
  60                                        server, flags,
  61                                        keytab, ticket);
  62 }
  63
  64 krb5_error_code
  65 krb5_recvauth_match_version(krb5_context context,
  66                             krb5_auth_context *auth_context,
  67                             krb5_pointer p_fd,
  68                             krb5_boolean (*match_appl_version)(const void *,
  69                                                                const char*),
  70                             const void *match_data,
  71                             krb5_principal server,
  72                             int32_t flags,
  73                             krb5_keytab keytab,
  74                             krb5_ticket **ticket)
  75 {
  76   krb5_error_code ret;
  77   const char *version = KRB5_SENDAUTH_VERSION;
  78   char her_version[sizeof(KRB5_SENDAUTH_VERSION)];
  79   char *her_appl_version;
  80   u_int32_t len;
  81   u_char repl;
  82   krb5_data data;
  83   krb5_flags ap_options;
  84   ssize_t n;
  85
  86   /*
  87    * If there are no addresses in auth_context, get them from `fd'.
  88    */
  89
  90   if (*auth_context == NULL) {
  91       ret = krb5_auth_con_init (context, auth_context);
  92       if (ret)
  93           return ret;
  94   }
  95
  96   ret = krb5_auth_con_setaddrs_from_fd (context,
  97                                         *auth_context,
  98                                         p_fd);
  99   if (ret)
 100       return ret;
 101
 102   if(!(flags & KRB5_RECVAUTH_IGNORE_VERSION)) {
 103     n = krb5_net_read (context, p_fd, &len, 4);
 104     if (n < 0) {
 105         ret = errno;
 106         krb5_set_error_string (context, "read: %s", strerror(errno));
 107         return ret;
 108     }
 109     if (n == 0) {
 110         krb5_clear_error_string (context);
 111         return KRB5_SENDAUTH_BADAUTHVERS;
 112     }
 113     len = ntohl(len);
 114     if (len != sizeof(her_version)
 115         || krb5_net_read (context, p_fd, her_version, len) != len
 116         || strncmp (version, her_version, len)) {
 117       repl = 1;
 118       krb5_net_write (context, p_fd, &repl, 1);
 119         krb5_clear_error_string (context);
 120       return KRB5_SENDAUTH_BADAUTHVERS;
 121     }
 122   }
 123
 124   n = krb5_net_read (context, p_fd, &len, 4);
 125   if (n < 0) {
 126       ret = errno;
 127       krb5_set_error_string (context, "read: %s", strerror(errno));
 128       return ret;
 129   }
 130   if (n == 0) {
 131       krb5_clear_error_string (context);
 132       return KRB5_SENDAUTH_BADAPPLVERS;
 133   }
 134   len = ntohl(len);
 135   her_appl_version = malloc (len);
 136   if (her_appl_version == NULL) {
 137       repl = 2;
 138       krb5_net_write (context, p_fd, &repl, 1);
 139       krb5_set_error_string (context, "malloc: out of memory");
 140       return ENOMEM;
 141   }
 142   if (krb5_net_read (context, p_fd, her_appl_version, len) != len
 143       || !(*match_appl_version)(match_data, her_appl_version)) {
 144     repl = 2;
 145     krb5_net_write (context, p_fd, &repl, 1);
 146     krb5_set_error_string (context, "wrong sendauth version (%s)",
 147                            her_appl_version);
 148     free (her_appl_version);
 149     return KRB5_SENDAUTH_BADAPPLVERS;
 150   }
 151   free (her_appl_version);
 152
 153   repl = 0;
 154   if (krb5_net_write (context, p_fd, &repl, 1) != 1) {
 155     ret = errno;
 156     krb5_set_error_string (context, "write: %s", strerror(errno));
 157     return ret;
 158   }
 159
 160   krb5_data_zero (&data);
 161   ret = krb5_read_message (context, p_fd, &data);
 162   if (ret)
 163       return ret;
 164
 165   ret = krb5_rd_req (context,
 166                      auth_context,
 167                      &data,
 168                      server,
 169                      keytab,
 170                      &ap_options,
 171                      ticket);
 172   krb5_data_free (&data);
 173   if (ret) {
 174       krb5_data error_data;
 175       krb5_error_code ret2;
 176
 177       ret2 = krb5_mk_error (context,
 178                             ret,
 179                             NULL,
 180                             NULL,
 181                             NULL,
 182                             server,
 183                             NULL,
 184                             NULL,
 185                             &error_data);
 186       if (ret2 == 0) {
 187           krb5_write_message (context, p_fd, &error_data);
 188           krb5_data_free (&error_data);
 189       }
 190       return ret;
 191   }
 192
 193   len = 0;
 194   if (krb5_net_write (context, p_fd, &len, 4) != 4) {
 195       ret = errno;
 196       krb5_set_error_string (context, "write: %s", strerror(errno));
 197       return ret;
 198   }
 199
 200   if (ap_options & AP_OPTS_MUTUAL_REQUIRED) {
 201     ret = krb5_mk_rep (context, *auth_context, &data);
 202     if (ret)
 203       return ret;
 204
 205     ret = krb5_write_message (context, p_fd, &data);
 206     if (ret)
 207         return ret;
 208     krb5_data_free (&data);
 209   }
 210   return 0;
 211 }