source3/auth/auth_script.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Call out to a shell script for an authentication check.
   5
   6    Copyright (C) Jeremy Allison 2005.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #include "includes.h"
  23 #include "auth.h"
  24
  25 #undef malloc
  26
  27 #undef DBGC_CLASS
  28 #define DBGC_CLASS DBGC_AUTH
  29
  30 /* Create a string containing the supplied :
  31  * domain\n
  32  * user\n
  33  * ascii hex challenge\n
  34  * ascii hex LM response\n
  35  * ascii hex NT response\n\0
  36  * and execute a shell script to check this.
  37  * Allows external programs to create users on demand.
  38  * Script returns zero on success, non-zero on fail.
  39  */
  40
  41 static NTSTATUS script_check_user_credentials(const struct auth_context *auth_context,
  42                                         void *my_private_data,
  43                                         TALLOC_CTX *mem_ctx,
  44                                         const struct auth_usersupplied_info *user_info,
  45                                         struct auth_serversupplied_info **server_info)
  46 {
  47         const char *script = lp_parm_const_string( GLOBAL_SECTION_SNUM, "auth_script", "script", NULL);
  48         char *secret_str;
  49         size_t secret_str_len;
  50         char hex_str[49];
  51         int ret, i;
  52
  53         if (!script) {
  54                 return NT_STATUS_INVALID_PARAMETER;
  55         }
  56
  57         if (!user_info) {
  58                 return NT_STATUS_INVALID_PARAMETER;
  59         }
  60
  61         if (!auth_context) {
  62                 DEBUG(3,("script_check_user_credentials: no auth_info !\n"));
  63                 return NT_STATUS_INVALID_PARAMETER;
  64         }
  65
  66         secret_str_len = strlen(user_info->mapped.domain_name) + 1 +
  67                         strlen(user_info->client.account_name) + 1 +
  68                         16 + 1 + /* 8 bytes of challenge going to 16 */
  69                         48 + 1 + /* 24 bytes of challenge going to 48 */
  70                         48 + 1;
  71
  72         secret_str = (char *)malloc(secret_str_len);
  73         if (!secret_str) {
  74                 return NT_STATUS_NO_MEMORY;
  75         }
  76
  77         if (strlcpy( secret_str, user_info->mapped.domain_name, secret_str_len) >= secret_str_len) {
  78                 /* Truncate. */
  79                 goto cat_out;
  80         }
  81         if (strlcat( secret_str, "\n", secret_str_len) >= secret_str_len) {
  82                 /* Truncate. */
  83                 goto cat_out;
  84         }
  85         if (strlcat( secret_str, user_info->client.account_name, secret_str_len) >= secret_str_len) {
  86                 /* Truncate. */
  87                 goto cat_out;
  88         }
  89         if (strlcat( secret_str, "\n", secret_str_len) >= secret_str_len) {
  90                 /* Truncate. */
  91                 goto cat_out;
  92         }
  93
  94         for (i = 0; i < 8; i++) {
  95                 slprintf(&hex_str[i*2], 3, "%02X", auth_context->challenge.data[i]);
  96         }
  97         if (strlcat( secret_str, hex_str, secret_str_len) >= secret_str_len) {
  98                 /* Truncate. */
  99                 goto cat_out;
 100         }
 101         if (strlcat( secret_str, "\n", secret_str_len) >= secret_str_len) {
 102                 /* Truncate. */
 103                 goto cat_out;
 104         }
 105
 106         if (user_info->password.response.lanman.data) {
 107                 for (i = 0; i < 24; i++) {
 108                         slprintf(&hex_str[i*2], 3, "%02X", user_info->password.response.lanman.data[i]);
 109                 }
 110                 if (strlcat( secret_str, hex_str, secret_str_len) >= secret_str_len) {
 111                         /* Truncate. */
 112                         goto cat_out;
 113                 }
 114         }
 115         if (strlcat( secret_str, "\n", secret_str_len) >= secret_str_len) {
 116                 /* Truncate. */
 117                 goto cat_out;
 118         }
 119
 120         if (user_info->password.response.nt.data) {
 121                 for (i = 0; i < 24; i++) {
 122                         slprintf(&hex_str[i*2], 3, "%02X", user_info->password.response.nt.data[i]);
 123                 }
 124                 if (strlcat( secret_str, hex_str, secret_str_len) >= secret_str_len) {
 125                         /* Truncate. */
 126                         goto cat_out;
 127                 }
 128         }
 129         if (strlcat( secret_str, "\n", secret_str_len) >= secret_str_len) {
 130                 /* Truncate. */
 131                 goto cat_out;
 132         }
 133
 134         DEBUG(10,("script_check_user_credentials: running %s with parameters:\n%s\n",
 135                 script, secret_str ));
 136
 137         ret = smbrunsecret( script, secret_str);
 138
 139         SAFE_FREE(secret_str);
 140
 141         if (ret) {
 142                 DEBUG(1,("script_check_user_credentials: failed to authenticate %s\\%s\n",
 143                         user_info->mapped.domain_name, user_info->client.account_name ));
 144                 /* auth failed. */
 145                 return NT_STATUS_NO_SUCH_USER;
 146         }
 147
 148         /* Cause the auth system to keep going.... */
 149         return NT_STATUS_NOT_IMPLEMENTED;
 150
 151   cat_out:
 152
 153         SAFE_FREE(secret_str);
 154         return NT_STATUS_NO_MEMORY;
 155 }
 156
 157 /* module initialisation */
 158 static NTSTATUS auth_init_script(struct auth_context *auth_context, const char *param, auth_methods **auth_method)
 159 {
 160         struct auth_methods *result;
 161
 162         result = talloc_zero(auth_context, struct auth_methods);
 163         if (result == NULL) {
 164                 return NT_STATUS_NO_MEMORY;
 165         }
 166         result->name = "script";
 167         result->auth = script_check_user_credentials;
 168
 169         if (param && *param) {
 170                 /* we load the 'fallback' module - if script isn't here, call this
 171                    module */
 172                 auth_methods *priv;
 173                 if (!load_auth_module(auth_context, param, &priv)) {
 174                         return NT_STATUS_UNSUCCESSFUL;
 175                 }
 176                 result->private_data = (void *)priv;
 177         }
 178
 179         *auth_method = result;
 180         return NT_STATUS_OK;
 181 }
 182
 183 NTSTATUS auth_script_init(void);
 184 NTSTATUS auth_script_init(void)
 185 {
 186         return smb_register_auth(AUTH_INTERFACE_VERSION, "script", auth_init_script);
 187 }