crypto/external/bsd/heimdal/dist/lib/krb5/get_default_principal.c

   1 /*      $NetBSD: get_default_principal.c,v 1.1.1.2 2014/04/24 12:45:50 pettai Exp $     */
   2
   3 /*
   4  * Copyright (c) 1997 - 2001 Kungliga Tekniska Högskolan
   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 /*
  39  * Try to find out what's a reasonable default principal.
  40  */
  41
  42 static const char*
  43 get_env_user(void)
  44 {
  45     const char *user = getenv("USER");
  46     if(user == NULL)
  47         user = getenv("LOGNAME");
  48     if(user == NULL)
  49         user = getenv("USERNAME");
  50     return user;
  51 }
  52
  53 #ifndef _WIN32
  54
  55 /*
  56  * Will only use operating-system dependant operation to get the
  57  * default principal, for use of functions that in ccache layer to
  58  * avoid recursive calls.
  59  */
  60
  61 krb5_error_code
  62 _krb5_get_default_principal_local (krb5_context context,
  63                                    krb5_principal *princ)
  64 {
  65     krb5_error_code ret;
  66     const char *user;
  67     uid_t uid;
  68
  69     *princ = NULL;
  70
  71     uid = getuid();
  72     if(uid == 0) {
  73         user = getlogin();
  74         if(user == NULL)
  75             user = get_env_user();
  76         if(user != NULL && strcmp(user, "root") != 0)
  77             ret = krb5_make_principal(context, princ, NULL, user, "root", NULL);
  78         else
  79             ret = krb5_make_principal(context, princ, NULL, "root", NULL);
  80     } else {
  81         struct passwd *pw = getpwuid(uid);
  82         if(pw != NULL)
  83             user = pw->pw_name;
  84         else {
  85             user = get_env_user();
  86             if(user == NULL)
  87                 user = getlogin();
  88         }
  89         if(user == NULL) {
  90             krb5_set_error_message(context, ENOTTY,
  91                                    N_("unable to figure out current "
  92                                       "principal", ""));
  93             return ENOTTY; /* XXX */
  94         }
  95         ret = krb5_make_principal(context, princ, NULL, user, NULL);
  96     }
  97     return ret;
  98 }
  99
 100 #else  /* _WIN32 */
 101
 102 #define SECURITY_WIN32
 103 #include <security.h>
 104
 105 krb5_error_code
 106 _krb5_get_default_principal_local(krb5_context context,
 107                                   krb5_principal *princ)
 108 {
 109     /* See if we can get the principal first.  We only expect this to
 110        work if logged into a domain. */
 111     {
 112         char username[1024];
 113         ULONG sz = sizeof(username);
 114
 115         if (GetUserNameEx(NameUserPrincipal, username, &sz)) {
 116             return krb5_parse_name_flags(context, username,
 117                                          KRB5_PRINCIPAL_PARSE_ENTERPRISE,
 118                                          princ);
 119         }
 120     }
 121
 122     /* Just get the Windows username.  This should pretty much always
 123        work. */
 124     {
 125         char username[1024];
 126         DWORD dsz = sizeof(username);
 127
 128         if (GetUserName(username, &dsz)) {
 129             return krb5_make_principal(context, princ, NULL, username, NULL);
 130         }
 131     }
 132
 133     /* Failing that, we look at the environment */
 134     {
 135         const char * username = get_env_user();
 136
 137         if (username == NULL) {
 138             krb5_set_error_string(context,
 139                                   "unable to figure out current principal");
 140             return ENOTTY;      /* Really? */
 141         }
 142
 143         return krb5_make_principal(context, princ, NULL, username, NULL);
 144     }
 145 }
 146
 147 #endif
 148
 149 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
 150 krb5_get_default_principal (krb5_context context,
 151                             krb5_principal *princ)
 152 {
 153     krb5_error_code ret;
 154     krb5_ccache id;
 155
 156     *princ = NULL;
 157
 158     ret = krb5_cc_default (context, &id);
 159     if (ret == 0) {
 160         ret = krb5_cc_get_principal (context, id, princ);
 161         krb5_cc_close (context, id);
 162         if (ret == 0)
 163             return 0;
 164     }
 165
 166     return _krb5_get_default_principal_local(context, princ);
 167 }