/* $Id: cfg.c,v 1.19 2003/12/19 05:35:14 reinelt Exp $^
*
* config file stuff
*
* Copyright 1999, 2000 Michael Reinelt <reinelt@eunet.at>
*
* This file is part of LCD4Linux.
*
* LCD4Linux is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* LCD4Linux is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*
* $Log: cfg.c,v $
* Revision 1.19 2003/12/19 05:35:14 reinelt
* renamed 'client' to 'plugin'
*
* Revision 1.18 2003/10/11 06:01:52 reinelt
*
* renamed expression.{c,h} to client.{c,h}
* added config file client
* new functions 'AddNumericVariable()' and 'AddStringVariable()'
* new parameter '-i' for interactive mode
*
* Revision 1.17 2003/10/05 17:58:50 reinelt
* libtool junk; copyright messages cleaned up
*
* Revision 1.16 2003/09/09 06:54:43 reinelt
* new function 'cfg_number()'
*
* Revision 1.15 2003/08/24 05:17:58 reinelt
* liblcd4linux patch from Patrick Schemitz
*
* Revision 1.14 2003/08/14 03:47:40 reinelt
* remove PID file if driver initialisation fails
*
* Revision 1.13 2003/02/22 07:53:10 reinelt
* cfg_get(key,defval)
*
* Revision 1.12 2001/03/09 12:14:24 reinelt
*
* minor cleanups
*
* Revision 1.11 2001/03/08 15:25:38 ltoetsch
* improved exec
*
* Revision 1.10 2001/03/07 18:10:21 ltoetsch
* added e(x)ec commands
*
* Revision 1.9 2000/08/10 09:44:09 reinelt
*
* new debugging scheme: error(), info(), debug()
* uses syslog if in daemon mode
*
* Revision 1.8 2000/07/31 06:46:35 reinelt
*
* eliminated some compiler warnings with glibc
*
* Revision 1.7 2000/04/15 11:13:54 reinelt
*
* added '-d' (debugging) switch
* added several debugging messages
* removed config entry 'Delay' for HD44780 driver
* delay loop for HD44780 will be calibrated automatically
*
* Revision 1.6 2000/04/03 04:46:38 reinelt
*
* added '-c key=val' option
*
* Revision 1.5 2000/03/28 07:22:15 reinelt
*
* version 0.95 released
* X11 driver up and running
* minor bugs fixed
*
* Revision 1.4 2000/03/26 20:00:44 reinelt
*
* README.Raster added
*
* Revision 1.3 2000/03/26 19:03:52 reinelt
*
* more Pixmap renaming
* quoting of '#' in config file
*
* Revision 1.2 2000/03/10 17:36:02 reinelt
*
* first unstable but running release
*
* Revision 1.1 2000/03/10 11:40:47 reinelt
* *** empty log message ***
*
* Revision 1.3 2000/03/07 11:01:34 reinelt
*
* system.c cleanup
*
* Revision 1.2 2000/03/06 06:04:06 reinelt
*
* minor cleanups
*
*/
/*
* exported functions:
*
* cfg_init (source)
* read configuration from source
* returns 0 if successful
* returns -1 in case of an error
*
* cfg_source (void)
* returns the file the configuration was read from
*
* cfg_cmd (arg)
* allows us to overwrite entries in the
* config-file from the command line.
* arg is 'key=value'
* cfg_cmd can be called _before_ cfg_read()
* returns 0 if ok, -1 if arg cannot be parsed
*
* cfg_get (key, defval)
* return the a value for a given key
* or <defval> if key does not exist
*
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#include <unistd.h>
#include <sys/stat.h>
#include "debug.h"
#include "cfg.h"
#include "plugin.h"
typedef struct {
char *key;
char *val;
int lock;
} ENTRY;
static char *Config_File=NULL;
static ENTRY *Config=NULL;
static int nConfig=0;
static char *strip (char *s, int strip_comments)
{
char *p;
while (isblank(*s)) s++;
for (p=s; *p; p++) {
if (*p=='"') do p++; while (*p && *p!='\n' && *p!='"');
if (*p=='\'') do p++; while (*p && *p!='\n' && *p!='\'');
if (*p=='\n' || (strip_comments && *p=='#' && (p==s || *(p-1)!='\\'))) {
*p='\0';
break;
}
}
for (p--; p>s && isblank(*p); p--) *p='\0';
return s;
}
static char *dequote (char *string)
{
char *s=string;
char *p=string;
do {
if (*s=='\\' && *(s+1)=='#') {
*p++=*++s;
} else {
*p++=*s;
}
} while (*s++);
return string;
}
static void cfg_add (char *key, char *val, int lock)
{
int i;
for (i=0; i<nConfig; i++) {
if (strcasecmp(Config[i].key, key)==0) {
if (Config[i].lock>lock) return;
if (Config[i].val) free (Config[i].val);
Config[i].val=dequote(strdup(val));
return;
}
}
nConfig++;
Config=realloc(Config, nConfig*sizeof(ENTRY));
Config[i].key=strdup(key);
Config[i].val=dequote(strdup(val));
Config[i].lock=lock;
}
int l4l_cfg_cmd (char *arg)
{
char *key, *val;
char buffer[256];
strncpy (buffer, arg, sizeof(buffer));
key=strip(buffer, 0);
for (val=key; *val; val++) {
if (*val=='=') {
*val++='\0';
break;
}
}
if (*key=='\0' || *val=='\0') return -1;
cfg_add (key, val, 1);
return 0;
}
char *l4l_cfg_get (char *key, char *defval)
{
int i;
for (i=0; i<nConfig; i++) {
if (strcasecmp(Config[i].key, key)==0) {
return Config[i].val;
}
}
return defval;
}
int l4l_cfg_number (char *key, int defval, int min, int max, int *value)
{
char *s, *e;
s=cfg_get(key, NULL);
if (s==NULL) {
*value=defval;
return 0;
}
*value=strtol(s, &e, 0);
if (*e!='\0') {
error ("bad %s entry '%s' in %s", key, s, cfg_source());
return -1;
}
if (*value<min) {
error ("bad %s value '%s' in %s, minimum is %d", key, s, cfg_source(), min);
return -1;
}
if (*value>max) {
error ("bad %s value '%s' in %s, maximum is %d", key, s, cfg_source(), max);
return -1;
}
return 0;
}
static int check_cfg_source(char *file)
{
/* as passwords and commands are stored in the config file,
* we will check that:
* - file is a normal file (or /dev/null)
* - file owner is owner of program
* - file is not accessible by group
* - file is not accessible by other
*/
struct stat stbuf;
uid_t uid, gid;
int error;
uid = geteuid();
gid = getegid();
if (stat(file, &stbuf) == -1) {
error ("stat(%s) failed: %s", file, strerror(errno));
return -1;
}
if (S_ISCHR(stbuf.st_mode) && strcmp(file, "/dev/null") == 0)
return 0;
error=0;
if (!S_ISREG(stbuf.st_mode)) {
error ("security error: '%s' is not a regular file", file);
error=-1;
}
if (stbuf.st_uid != uid || stbuf.st_gid != gid) {
error ("security error: owner and/or group of '%s' don't match", file);
error=-1;
}
if (stbuf.st_mode & S_IRWXG || stbuf.st_mode & S_IRWXO) {
error ("security error: group or other have access to '%s'", file);
error=-1;
}
return error;
}
static void cfg_plugin (RESULT *result, RESULT *arg1)
{
char *value=cfg_get(R2S(arg1), "");
SetResult(&result, R_STRING, value);
}
int l4l_cfg_init (char *file)
{
FILE *stream;
char buffer[256];
char *line, *p, *s;
if (check_cfg_source(file) == -1) {
error("config file '%s' is insecure, aborting", file);
return -1;
}
stream=fopen (file, "r");
if (stream==NULL) {
error ("open(%s) failed: %s", file, strerror(errno));
return -1;
}
if (Config_File) free (Config_File);
Config_File=strdup(file);
while ((line=fgets(buffer,256,stream))!=NULL) {
if (*(line=strip(line, 1))=='\0') continue;
for (p=line; *p; p++) {
if (isblank(*p)) {
*p++='\0';
break;
}
}
p=strip(p, 1);
if (*p) for (s=p; *(s+1); s++);
else s=p;
if (*p=='"' && *s=='"') {
*s='\0';
p++;
}
else if (*p=='\'' && *s=='\'') {
*s='\0';
p++;
}
cfg_add (line, p, 0);
}
fclose (stream);
// register as a plugin
AddFunction ("cfg", 1, cfg_plugin);
return 0;
}
char *l4l_cfg_source (void)
{
if (Config_File)
return Config_File;
else
return "";
}
int (*cfg_init) (char *source) = l4l_cfg_init;
char *(*cfg_source) (void) = l4l_cfg_source;
int (*cfg_cmd) (char *arg) = l4l_cfg_cmd;
char *(*cfg_get) (char *key, char *defval) = l4l_cfg_get;
int (*cfg_number) (char *key, int defval,
int min, int max, int *value) = l4l_cfg_number;