source/lib/substitute.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 3.0
   4    string substitution functions
   5    Copyright (C) Andrew Tridgell 1992-2000
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22
  23 #include "includes.h"
  24
  25 fstring local_machine="";
  26 fstring remote_arch="UNKNOWN";
  27 userdom_struct current_user_info;
  28 pstring samlogon_user="";
  29 BOOL sam_logon_in_ssb = False;
  30 fstring remote_proto="UNKNOWN";
  31 fstring remote_machine="";
  32 static fstring smb_user_name;
  33
  34
  35 /*
  36   setup the string used by %U substitution
  37 */
  38 void sub_set_smb_name(const char *name)
  39 {
  40         fstring tmp;
  41
  42         /* ignore anonymous settings */
  43         if (! *name) return;
  44
  45         fstrcpy(tmp,name);
  46         trim_string(tmp," "," ");
  47         strlower(tmp);
  48         alpha_strcpy(smb_user_name,tmp,SAFE_NETBIOS_CHARS,sizeof(smb_user_name)-1);
  49 }
  50
  51 const char* get_remote_machine_name(void)
  52 {
  53                 return remote_machine;
  54 }
  55
  56
  57 /*******************************************************************
  58  Given a pointer to a %$(NAME) expand it as an environment variable.
  59  Return the number of characters by which the pointer should be advanced.
  60  Based on code by Branko Cibej <branko.cibej@hermes.si>
  61  When this is called p points at the '%' character.
  62 ********************************************************************/
  63
  64 static size_t expand_env_var(char *p, int len)
  65 {
  66         fstring envname;
  67         char *envval;
  68         char *q, *r;
  69         int copylen;
  70
  71         if (p[1] != '$')
  72                 return 1;
  73
  74         if (p[2] != '(')
  75                 return 2;
  76
  77         /*
  78          * Look for the terminating ')'.
  79          */
  80
  81         if ((q = strchr(p,')')) == NULL) {
  82                 DEBUG(0,("expand_env_var: Unterminated environment variable [%s]\n", p));
  83                 return 2;
  84         }
  85
  86         /*
  87          * Extract the name from within the %$(NAME) string.
  88          */
  89
  90         r = p+3;
  91         copylen = MIN((q-r),(sizeof(envname)-1));
  92         strncpy(envname,r,copylen);
  93         envname[copylen] = '\0';
  94
  95         if ((envval = getenv(envname)) == NULL) {
  96                 DEBUG(0,("expand_env_var: Environment variable [%s] not set\n", envname));
  97                 return 2;
  98         }
  99
 100         /*
 101          * Copy the full %$(NAME) into envname so it
 102          * can be replaced.
 103          */
 104
 105         copylen = MIN((q+1-p),(sizeof(envname)-1));
 106         strncpy(envname,p,copylen);
 107         envname[copylen] = '\0';
 108         string_sub(p,envname,envval,len);
 109         return 0; /* Allow the environment contents to be parsed. */
 110 }
 111
 112 /*******************************************************************
 113  Patch from jkf@soton.ac.uk
 114  Added this to implement %p (NIS auto-map version of %H)
 115 *******************************************************************/
 116
 117 static char *automount_path(char *user_name)
 118 {
 119         static pstring server_path;
 120
 121         /* use the passwd entry as the default */
 122         /* this will be the default if WITH_AUTOMOUNT is not used or fails */
 123
 124         pstrcpy(server_path, get_user_home_dir(user_name));
 125
 126 #if (defined(HAVE_NETGROUP) && defined (WITH_AUTOMOUNT))
 127
 128         if (lp_nis_home_map()) {
 129                 char *home_path_start;
 130                 char *automount_value = automount_lookup(user_name);
 131
 132                 if(strlen(automount_value) > 0) {
 133                         home_path_start = strchr(automount_value,':');
 134                         if (home_path_start != NULL) {
 135                                 DEBUG(5, ("NIS lookup succeeded.  Home path is: %s\n",
 136                                                 home_path_start?(home_path_start+1):""));
 137                                 pstrcpy(server_path, home_path_start+1);
 138                         }
 139                 } else {
 140                         /* NIS key lookup failed: default to user home directory from password file */
 141                         DEBUG(5, ("NIS lookup failed. Using Home path from passwd file. Home path is: %s\n", server_path ));
 142                 }
 143         }
 144 #endif
 145
 146         DEBUG(4,("Home server path: %s\n", server_path));
 147
 148         return server_path;
 149 }
 150
 151 /*******************************************************************
 152  Patch from jkf@soton.ac.uk
 153  This is Luke's original function with the NIS lookup code
 154  moved out to a separate function.
 155 *******************************************************************/
 156
 157 static char *automount_server(char *user_name)
 158 {
 159         extern pstring global_myname;
 160         static pstring server_name;
 161
 162         /* use the local machine name as the default */
 163         /* this will be the default if WITH_AUTOMOUNT is not used or fails */
 164         if (*local_machine)
 165                 pstrcpy(server_name, local_machine);
 166         else
 167                 pstrcpy(server_name, global_myname);
 168
 169 #if (defined(HAVE_NETGROUP) && defined (WITH_AUTOMOUNT))
 170
 171         if (lp_nis_home_map()) {
 172                 int home_server_len;
 173                 char *automount_value = automount_lookup(user_name);
 174                 home_server_len = strcspn(automount_value,":");
 175                 DEBUG(5, ("NIS lookup succeeded.  Home server length: %d\n",home_server_len));
 176                 if (home_server_len > sizeof(pstring))
 177                         home_server_len = sizeof(pstring);
 178                 strncpy(server_name, automount_value, home_server_len);
 179                 server_name[home_server_len] = '\0';
 180         }
 181 #endif
 182
 183         DEBUG(4,("Home server: %s\n", server_name));
 184
 185         return server_name;
 186 }
 187
 188 /****************************************************************************
 189  Do some standard substitutions in a string.
 190 ****************************************************************************/
 191
 192 void standard_sub_basic(char *str, int len)
 193 {
 194         extern pstring global_myname;
 195         char *p, *s;
 196         fstring pidstr;
 197         struct passwd *pass;
 198
 199         for (s=str; (p=strchr(s, '%'));s=p) {
 200                 fstring tmp_str;
 201
 202                 int l = len - (int)(p-str);
 203
 204                 switch (*(p+1)) {
 205                 case 'U' :
 206                         fstrcpy(tmp_str, sam_logon_in_ssb?samlogon_user:smb_user_name);
 207                         strlower(tmp_str);
 208                         string_sub(p,"%U",tmp_str,l);
 209                         break;
 210                 case 'G' :
 211                         fstrcpy(tmp_str, sam_logon_in_ssb?samlogon_user:smb_user_name);
 212                         if ((pass = Get_Pwnam(tmp_str, False))!=NULL) {
 213                                 string_sub(p,"%G",gidtoname(pass->pw_gid),l);
 214                         } else {
 215                                 p += 2;
 216                         }
 217                         break;
 218                 case 'D' :
 219                         fstrcpy(tmp_str, current_user_info.domain);
 220                         strupper(tmp_str);
 221                         string_sub(p,"%D", tmp_str,l);
 222                         break;
 223                 case 'I' : string_sub(p,"%I", client_addr(),l); break;
 224                 case 'L' :
 225                         if (*local_machine)
 226                                 string_sub(p,"%L", local_machine,l);
 227                         else {
 228                                 pstring temp_name;
 229
 230                                 pstrcpy(temp_name, global_myname);
 231                                 strlower(temp_name);
 232                                 string_sub(p,"%L", temp_name,l);
 233                         }
 234                         break;
 235                 case 'M' : string_sub(p,"%M", client_name(),l); break;
 236                 case 'R' : string_sub(p,"%R", remote_proto,l); break;
 237                 case 'T' : string_sub(p,"%T", timestring(False),l); break;
 238                 case 'a' : string_sub(p,"%a", remote_arch,l); break;
 239                 case 'd' :
 240                         slprintf(pidstr,sizeof(pidstr)-1, "%d",(int)sys_getpid());
 241                         string_sub(p,"%d", pidstr,l);
 242                         break;
 243                 case 'h' : string_sub(p,"%h", myhostname(),l); break;
 244                 case 'm' : string_sub(p,"%m", remote_machine,l); break;
 245                 case 'v' : string_sub(p,"%v", VERSION,l); break;
 246                 case '$' : p += expand_env_var(p,l); break; /* Expand environment variables */
 247                 case '\0':
 248                         p++;
 249                         break; /* don't run off the end of the string */
 250
 251                 default: p+=2;
 252                         break;
 253                 }
 254         }
 255 }
 256
 257 /****************************************************************************
 258  Do some standard substitutions in a string.
 259 ****************************************************************************/
 260
 261 void standard_sub_advanced(int snum, char *user, char *connectpath, gid_t gid, char *str, int len)
 262 {
 263         char *p, *s, *home;
 264
 265         for (s=str; (p=strchr(s, '%'));s=p) {
 266                 int l = len - (int)(p-str);
 267
 268                 switch (*(p+1)) {
 269                 case 'N' : string_sub(p,"%N", automount_server(user),l); break;
 270                 case 'H':
 271                         if ((home = get_user_home_dir(user))) {
 272                                 string_sub(p,"%H",home, l);
 273                         } else {
 274                                 p += 2;
 275                         }
 276                         break;
 277                 case 'P':
 278                         string_sub(p,"%P", connectpath, l);
 279                         break;
 280
 281                 case 'S':
 282                         string_sub(p,"%S", lp_servicename(snum), l);
 283                         break;
 284
 285                 case 'g':
 286                         string_sub(p,"%g", gidtoname(gid), l);
 287                         break;
 288                 case 'u':
 289                         string_sub(p,"%u", user, l);
 290                         break;
 291
 292                         /* Patch from jkf@soton.ac.uk Left the %N (NIS
 293                          * server name) in standard_sub_basic as it is
 294                          * a feature for logon servers, hence uses the
 295                          * username.  The %p (NIS server path) code is
 296                          * here as it is used instead of the default
 297                          * "path =" string in [homes] and so needs the
 298                          * service name, not the username.  */
 299                 case 'p':
 300                         string_sub(p,"%p", automount_path(lp_servicename(snum)), l);
 301                         break;
 302                 case '\0':
 303                         p++;
 304                         break; /* don't run off the end of the string */
 305
 306                 default: p+=2;
 307                         break;
 308                 }
 309         }
 310
 311         standard_sub_basic(str,len);
 312 }
 313
 314 /****************************************************************************
 315  Do some standard substitutions in a string.
 316 ****************************************************************************/
 317
 318 void standard_sub_conn(connection_struct *conn, char *str, int len)
 319 {
 320         standard_sub_advanced(SNUM(conn), conn->user, conn->connectpath, conn->gid, str, len);
 321 }
 322
 323 /****************************************************************************
 324  Like standard_sub but for a homes share where snum still points to the [homes]
 325  share. No user specific snum created yet so servicename should be the username.
 326 ****************************************************************************/
 327
 328 void standard_sub_home(int snum, char *user, char *str, int len)
 329 {
 330         char *p, *s;
 331
 332         for (s=str; (p=strchr(s, '%'));s=p) {
 333                 int l = len - (int)(p-str);
 334
 335                 switch (*(p+1)) {
 336                 case 'S':
 337                         string_sub(p,"%S", user, l);
 338                         break;
 339                 case 'p':
 340                         string_sub(p,"%p", automount_path(user), l);
 341                         break;
 342                 case '\0':
 343                         p++;
 344                         break; /* don't run off the end of the string */
 345
 346                 default: p+=2;
 347                         break;
 348                 }
 349         }
 350
 351         standard_sub_advanced(snum, user, "", -1, str, len);
 352 }
 353
 354 /****************************************************************************
 355  Like standard_sub but by snum.
 356 ****************************************************************************/
 357
 358 void standard_sub_snum(int snum, char *str, int len)
 359 {
 360         extern struct current_user current_user;
 361         static uid_t cached_uid = -1;
 362         static fstring cached_user;
 363         /* calling uidtoname() on every substitute would be too expensive, so
 364            we cache the result here as nearly every call is for the same uid */
 365
 366         if (cached_uid != current_user.uid) {
 367                 fstrcpy(cached_user, uidtoname(current_user.uid));
 368                 cached_uid = current_user.uid;
 369         }
 370
 371         standard_sub_advanced(snum, cached_user, "", -1, str, len);
 372 }
 373
 374 /*******************************************************************
 375  Substitute strings with useful parameters.
 376 ********************************************************************/
 377
 378 void standard_sub_vuser(char *str, int len, user_struct *vuser)
 379 {
 380         standard_sub_advanced(-1, vuser->user.unix_name, "", -1, str, len);
 381 }
 382
 383 /*******************************************************************
 384  Substitute strings with useful parameters.
 385 ********************************************************************/
 386
 387 void standard_sub_vsnum(char *str, int len, user_struct *vuser, int snum)
 388 {
 389         standard_sub_advanced(snum, vuser->user.unix_name, "", -1, str, len);
 390 }