1/* $NetBSD: get_default_principal.c,v 1.4 2023/06/19 21:41:44 christos Exp $ */ 2 3/* 4 * Copyright (c) 1997 - 2001 Kungliga Tekniska H��gskolan 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 42static const char* 43get_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 61KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL 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, *pwd = NULL; 82 char pwbuf[2048]; 83 84 if (rk_getpwuid_r(uid, &pw, pwbuf, sizeof(pwbuf), &pwd) == 0) 85 user = pwd->pw_name; 86 else { 87 user = get_env_user(); 88 if(user == NULL) 89 user = getlogin(); 90 } 91 if(user == NULL) { 92 krb5_set_error_message(context, ENOTTY, 93 N_("unable to figure out current " 94 "principal", "")); 95 return ENOTTY; /* XXX */ 96 } 97 ret = krb5_make_principal(context, princ, NULL, user, NULL); 98 } 99 return ret; 100} 101 102#else /* _WIN32 */ 103 104#define SECURITY_WIN32 105#include <security.h> 106 107KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL 108_krb5_get_default_principal_local(krb5_context context, 109 krb5_principal *princ) 110{ 111 /* See if we can get the principal first. We only expect this to 112 work if logged into a domain. */ 113 { 114 char username[1024]; 115 ULONG sz = sizeof(username); 116 117 if (GetUserNameEx(NameUserPrincipal, username, &sz)) { 118 return krb5_parse_name_flags(context, username, 119 KRB5_PRINCIPAL_PARSE_ENTERPRISE, 120 princ); 121 } 122 } 123 124 /* Just get the Windows username. This should pretty much always 125 work. */ 126 { 127 char username[1024]; 128 DWORD dsz = sizeof(username); 129 130 if (GetUserName(username, &dsz)) { 131 return krb5_make_principal(context, princ, NULL, username, NULL); 132 } 133 } 134 135 /* Failing that, we look at the environment */ 136 { 137 const char * username = get_env_user(); 138 139 if (username == NULL) { 140 krb5_set_error_string(context, 141 "unable to figure out current principal"); 142 return ENOTTY; /* Really? */ 143 } 144 145 return krb5_make_principal(context, princ, NULL, username, NULL); 146 } 147} 148 149#endif 150 151KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL 152krb5_get_default_principal (krb5_context context, 153 krb5_principal *princ) 154{ 155 krb5_error_code ret; 156 krb5_ccache id; 157 158 *princ = NULL; 159 160 ret = krb5_cc_default (context, &id); 161 if (ret == 0) { 162 ret = krb5_cc_get_principal (context, id, princ); 163 krb5_cc_close (context, id); 164 if (ret == 0) 165 return 0; 166 } 167 168 return _krb5_get_default_principal_local(context, princ); 169} 170