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 extern int DEBUGLEVEL;
  26
  27 fstring local_machine="";
  28 fstring remote_arch="UNKNOWN";
  29 userdom_struct current_user_info;
  30 pstring samlogon_user="";
  31 BOOL sam_logon_in_ssb = False;
  32 fstring remote_proto="UNKNOWN";
  33 fstring remote_machine="";
  34
  35
  36 /*******************************************************************
  37  Given a pointer to a %$(NAME) expand it as an environment variable.
  38  Return the number of characters by which the pointer should be advanced.
  39  Based on code by Branko Cibej <branko.cibej@hermes.si>
  40  When this is called p points at the '%' character.
  41 ********************************************************************/
  42 static size_t expand_env_var(char *p, int len)
  43 {
  44         fstring envname;
  45         char *envval;
  46         char *q, *r;
  47         int copylen;
  48
  49         if (p[1] != '$')
  50                 return 1;
  51
  52         if (p[2] != '(')
  53                 return 2;
  54
  55         /*
  56          * Look for the terminating ')'.
  57          */
  58
  59         if ((q = strchr(p,')')) == NULL) {
  60                 DEBUG(0,("expand_env_var: Unterminated environment variable [%s]\n", p));
  61                 return 2;
  62         }
  63
  64         /*
  65          * Extract the name from within the %$(NAME) string.
  66          */
  67
  68         r = p+3;
  69         copylen = MIN((q-r),(sizeof(envname)-1));
  70         strncpy(envname,r,copylen);
  71         envname[copylen] = '\0';
  72
  73         if ((envval = getenv(envname)) == NULL) {
  74                 DEBUG(0,("expand_env_var: Environment variable [%s] not set\n", envname));
  75                 return 2;
  76         }
  77
  78         /*
  79          * Copy the full %$(NAME) into envname so it
  80          * can be replaced.
  81          */
  82
  83         copylen = MIN((q+1-p),(sizeof(envname)-1));
  84         strncpy(envname,p,copylen);
  85         envname[copylen] = '\0';
  86         string_sub(p,envname,envval,len);
  87         return 0; /* Allow the environment contents to be parsed. */
  88 }
  89
  90 /*******************************************************************
  91  Patch from jkf@soton.ac.uk
  92  Added this to implement %p (NIS auto-map version of %H)
  93 *******************************************************************/
  94 static char *automount_path(char *user_name)
  95 {
  96         static pstring server_path;
  97
  98         /* use the passwd entry as the default */
  99         /* this will be the default if WITH_AUTOMOUNT is not used or fails */
 100         /* pstrcpy() copes with get_user_home_dir() returning NULL */
 101         pstrcpy(server_path, get_user_home_dir(user_name));
 102
 103 #if (defined(HAVE_NETGROUP) && defined (WITH_AUTOMOUNT))
 104
 105         if (lp_nis_home_map()) {
 106                 char *home_path_start;
 107                 char *automount_value = automount_lookup(user_name);
 108
 109                 if(strlen(automount_value) > 0) {
 110                         home_path_start = strchr(automount_value,':');
 111                         if (home_path_start != NULL) {
 112                                 DEBUG(5, ("NIS lookup succeeded.  Home path is: %s\n",
 113                                                 home_path_start?(home_path_start+1):""));
 114                                 pstrcpy(server_path, home_path_start+1);
 115                         }
 116                 } else {
 117                         /* NIS key lookup failed: default to user home directory from password file */
 118           pstrcpy(server_path, get_user_home_dir(user_name));
 119                   DEBUG(5, ("NIS lookup failed. Using Home path from passwd file. Home path is: %s\n",
 120                         server_path ));
 121                 }
 122         }
 123 #endif
 124
 125         DEBUG(4,("Home server path: %s\n", server_path));
 126
 127         return server_path;
 128 }
 129
 130
 131 /*******************************************************************
 132  Patch from jkf@soton.ac.uk
 133  This is Luke's original function with the NIS lookup code
 134  moved out to a separate function.
 135 *******************************************************************/
 136 static char *automount_server(char *user_name)
 137 {
 138         static pstring server_name;
 139
 140         /* use the local machine name as the default */
 141         /* this will be the default if WITH_AUTOMOUNT is not used or fails */
 142         pstrcpy(server_name, local_machine);
 143
 144 #if (defined(HAVE_NETGROUP) && defined (WITH_AUTOMOUNT))
 145
 146         if (lp_nis_home_map())
 147         {
 148                 int home_server_len;
 149                 char *automount_value = automount_lookup(user_name);
 150                 home_server_len = strcspn(automount_value,":");
 151                 DEBUG(5, ("NIS lookup succeeded.  Home server length: %d\n",home_server_len));
 152                 if (home_server_len > sizeof(pstring))
 153                 {
 154                         home_server_len = sizeof(pstring);
 155                 }
 156                 strncpy(server_name, automount_value, home_server_len);
 157                 server_name[home_server_len] = '\0';
 158         }
 159 #endif
 160
 161         DEBUG(4,("Home server: %s\n", server_name));
 162
 163         return server_name;
 164 }
 165
 166 /****************************************************************************
 167  Do some standard substitutions in a string.
 168 ****************************************************************************/
 169 void standard_sub_basic(char *str)
 170 {
 171         char *p, *s;
 172         fstring pidstr;
 173
 174         for (s=str; (p=strchr(s, '%'));s=p) {
 175                 fstring tmp_str;
 176
 177                 int l = sizeof(pstring) - (int)(p-str);
 178
 179                 switch (*(p+1)) {
 180                 case 'U' :
 181                         fstrcpy(tmp_str, sam_logon_in_ssb?samlogon_user:current_user_info.smb_name);
 182                         strlower(tmp_str);
 183                         string_sub(p,"%U",tmp_str,l);
 184                         break;
 185                 case 'D' :
 186                         fstrcpy(tmp_str, current_user_info.domain);
 187                         strupper(tmp_str);
 188                         string_sub(p,"%D", tmp_str,l);
 189                         break;
 190                 case 'I' : string_sub(p,"%I", client_addr(),l); break;
 191                 case 'L' : string_sub(p,"%L", local_machine,l); break;
 192                 case 'M' : string_sub(p,"%M", client_name(),l); break;
 193                 case 'R' : string_sub(p,"%R", remote_proto,l); break;
 194                 case 'T' : string_sub(p,"%T", timestring(False),l); break;
 195                 case 'a' : string_sub(p,"%a", remote_arch,l); break;
 196                 case 'd' :
 197                         slprintf(pidstr,sizeof(pidstr)-1, "%d",(int)sys_getpid());
 198                         string_sub(p,"%d", pidstr,l);
 199                         break;
 200                 case 'h' : string_sub(p,"%h", myhostname(),l); break;
 201                 case 'm' : string_sub(p,"%m", remote_machine,l); break;
 202                 case 'v' : string_sub(p,"%v", VERSION,l); break;
 203                 case '$' : p += expand_env_var(p,l); break; /* Expand environment variables */
 204                 case '\0':
 205                         p++;
 206                         break; /* don't run off the end of the string */
 207
 208                 default: p+=2;
 209                         break;
 210                 }
 211         }
 212 }
 213
 214
 215 /****************************************************************************
 216  Do some standard substitutions in a string.
 217 ****************************************************************************/
 218 void standard_sub_advanced(int snum, char *user, char *connectpath, gid_t gid, char *str)
 219 {
 220         char *p, *s, *home;
 221         struct passwd *pass;
 222
 223         for (s=str; (p=strchr(s, '%'));s=p) {
 224                 int l = sizeof(pstring) - (int)(p-str);
 225
 226                 switch (*(p+1)) {
 227                 case 'G' :
 228                         if ((pass = Get_Pwnam(user,False))!=NULL) {
 229                                 string_sub(p,"%G",gidtoname(pass->pw_gid),l);
 230                         } else {
 231                                 p += 2;
 232                         }
 233                         break;
 234                 case 'N' : string_sub(p,"%N", automount_server(user),l); break;
 235                 case 'H':
 236                         if ((home = get_user_home_dir(user))) {
 237                                 string_sub(p,"%H",home, l);
 238                         } else {
 239                                 p += 2;
 240                         }
 241                         break;
 242                 case 'P':
 243                         string_sub(p,"%P", connectpath, l);
 244                         break;
 245
 246                 case 'S':
 247                         string_sub(p,"%S", lp_servicename(snum), l);
 248                         break;
 249
 250                 case 'g':
 251                         string_sub(p,"%g", gidtoname(gid), l);
 252                         break;
 253                 case 'u':
 254                         string_sub(p,"%u", user, l);
 255                         break;
 256
 257                         /* Patch from jkf@soton.ac.uk Left the %N (NIS
 258                          * server name) in standard_sub_basic as it is
 259                          * a feature for logon servers, hence uses the
 260                          * username.  The %p (NIS server path) code is
 261                          * here as it is used instead of the default
 262                          * "path =" string in [homes] and so needs the
 263                          * service name, not the username.  */
 264                 case 'p':
 265                         string_sub(p,"%p", automount_path(lp_servicename(snum)), l);
 266                         break;
 267                 case '\0':
 268                         p++;
 269                         break; /* don't run off the end of the string */
 270
 271                 default: p+=2;
 272                         break;
 273                 }
 274         }
 275
 276         standard_sub_basic(str);
 277 }
 278
 279 /****************************************************************************
 280  Do some standard substitutions in a string.
 281 ****************************************************************************/
 282 void standard_sub_conn(connection_struct *conn, char *str)
 283 {
 284         standard_sub_advanced(SNUM(conn), conn->user, conn->connectpath, conn->gid, str);
 285 }
 286
 287 /****************************************************************************
 288 like standard_sub but by snum
 289 ****************************************************************************/
 290 void standard_sub_snum(int snum, char *str)
 291 {
 292         extern struct current_user current_user;
 293         static uid_t cached_uid = -1;
 294         static fstring cached_user;
 295         /* calling uidtoname() on every substitute would be too expensive, so
 296            we cache the result here as nearly every call is for the same uid */
 297
 298         if (cached_uid != current_user.uid) {
 299                 fstrcpy(cached_user, uidtoname(current_user.uid));
 300                 cached_uid = current_user.uid;
 301         }
 302
 303         standard_sub_advanced(snum, cached_user, "", -1, str);
 304 }
 305
 306 /*******************************************************************
 307  Substitute strings with useful parameters.
 308 ********************************************************************/
 309 void standard_sub_vuser(char *str, user_struct *vuser)
 310 {
 311         standard_sub_advanced(-1, vuser->user.unix_name, "", -1, str);
 312 }
 313
 314 /*******************************************************************
 315  Substitute strings with useful parameters.
 316 ********************************************************************/
 317 void standard_sub_vsnum(char *str, user_struct *vuser, int snum)
 318 {
 319         standard_sub_advanced(snum, vuser->user.unix_name, "", -1, str);
 320 }
 321