systems.c revision 30913 
1/*
2 *	          System configuration routines
3 *
4 *	    Written by Toshiharu OHNO (tony-o@iij.ad.jp)
5 *
6 *   Copyright (C) 1993, Internet Initiative Japan, Inc. All rights reserverd.
7 *
8 * Redistribution and use in source and binary forms are permitted
9 * provided that the above copyright notice and this paragraph are
10 * duplicated in all such forms and that any documentation,
11 * advertising materials, and other materials related to such
12 * distribution and use acknowledge that the software was developed
13 * by the Internet Initiative Japan, Inc.  The name of the
14 * IIJ may not be used to endorse or promote products derived
15 * from this software without specific prior written permission.
16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
18 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
19 *
20 * $Id: systems.c,v 1.17 1997/10/26 01:03:48 brian Exp $
21 *
22 *  TODO:
23 */
24#include <sys/param.h>
25#include <netinet/in.h>
26
27#include <stdio.h>
28#include <stdlib.h>
29#include <string.h>
30#include <unistd.h>
31
32#include "mbuf.h"
33#include "log.h"
34#include "defs.h"
35#include "timer.h"
36#include "fsm.h"
37#include "loadalias.h"
38#include "command.h"
39#include "ipcp.h"
40#include "pathnames.h"
41#include "vars.h"
42#include "server.h"
43#include "systems.h"
44
45static int uid;
46static int gid;
47static int euid;
48static int egid;
49static int usermode;
50
51int
52OrigUid()
53{
54  return uid;
55}
56
57void
58GetUid()
59{
60  uid = getuid();
61  gid = getgid();
62  euid = geteuid();
63  egid = getegid();
64  usermode = 0;
65}
66
67static void
68SetUserId()
69{
70  if (!usermode) {
71    if (setreuid(euid, uid) == -1) {
72      LogPrintf(LogERROR, "unable to setreuid!\n");
73      ServerClose();
74      exit(1);
75    }
76    if (setregid(egid, gid) == -1) {
77      LogPrintf(LogERROR, "unable to setregid!\n");
78      ServerClose();
79      exit(1);
80    }
81    usermode = 1;
82  }
83}
84
85static void
86SetPppId()
87{
88  if (usermode) {
89    if (setreuid(uid, euid) == -1) {
90      LogPrintf(LogERROR, "unable to setreuid!\n");
91      ServerClose();
92      exit(1);
93    }
94    if (setregid(gid, egid) == -1) {
95      LogPrintf(LogERROR, "unable to setregid!\n");
96      ServerClose();
97      exit(1);
98    }
99    usermode = 0;
100  }
101}
102
103FILE *
104OpenSecret(char *file)
105{
106  FILE *fp;
107  char *cp;
108  char line[100];
109
110  fp = NULL;
111  cp = getenv("HOME");
112  if (cp) {
113    SetUserId();
114    snprintf(line, sizeof line, "%s/.%s", cp, file);
115    fp = fopen(line, "r");
116  }
117  if (fp == NULL) {
118    SetPppId();
119    snprintf(line, sizeof line, "%s/%s", _PATH_PPP, file);
120    fp = fopen(line, "r");
121  }
122  if (fp == NULL) {
123    LogPrintf(LogWARN, "OpenSecret: Can't open %s.\n", line);
124    SetPppId();
125    return (NULL);
126  }
127  return (fp);
128}
129
130void
131CloseSecret(FILE * fp)
132{
133  fclose(fp);
134  SetPppId();
135}
136
137int
138SelectSystem(char *name, char *file)
139{
140  FILE *fp;
141  char *cp, *wp;
142  int n, len;
143  u_char olauth;
144  char line[200];
145  char filename[200];
146  int linenum;
147
148  fp = NULL;
149  cp = getenv("HOME");
150  if (cp) {
151    SetUserId();
152    snprintf(filename, sizeof filename, "%s/.%s", cp, file);
153    fp = fopen(filename, "r");
154  }
155  if (fp == NULL) {
156    SetPppId();			/* fix from pdp@ark.jr3uom.iijnet.or.jp */
157    snprintf(filename, sizeof filename, "%s/%s", _PATH_PPP, file);
158    fp = fopen(filename, "r");
159  }
160  if (fp == NULL) {
161    LogPrintf(LogDEBUG, "SelectSystem: Can't open %s.\n", filename);
162    SetPppId();
163    return (-1);
164  }
165  LogPrintf(LogDEBUG, "SelectSystem: Checking %s (%s).\n", name, filename);
166
167  linenum = 0;
168  while (fgets(line, sizeof(line), fp)) {
169    linenum++;
170    cp = line;
171    switch (*cp) {
172    case '#':			/* comment */
173      break;
174    case ' ':
175    case '\t':
176      break;
177    default:
178      wp = strpbrk(cp, ":\n");
179      if (wp == NULL) {
180	LogPrintf(LogWARN, "Bad rule in %s (line %d) - missing colon.\n",
181		  filename, linenum);
182	ServerClose();
183	exit(1);
184      }
185      *wp = '\0';
186      if (strcmp(cp, name) == 0) {
187	while (fgets(line, sizeof(line), fp)) {
188	  cp = line;
189	  if (*cp == ' ' || *cp == '\t') {
190	    n = strspn(cp, " \t");
191	    cp += n;
192            len = strlen(cp);
193            if (!len)
194              continue;
195            if (cp[len-1] == '\n')
196              cp[--len] = '\0';
197            if (!len)
198              continue;
199	    LogPrintf(LogCOMMAND, "%s: %s\n", name, cp);
200	    SetPppId();
201	    olauth = VarLocalAuth;
202	    if (VarLocalAuth == LOCAL_NO_AUTH)
203	      VarLocalAuth = LOCAL_AUTH;
204	    DecodeCommand(cp, len, 0);
205	    VarLocalAuth = olauth;
206	    SetUserId();
207	  } else if (*cp == '#') {
208	    continue;
209	  } else
210	    break;
211	}
212	fclose(fp);
213	SetPppId();
214	return (0);
215      }
216      break;
217    }
218  }
219  fclose(fp);
220  SetPppId();
221  return -1;
222}
223
224int
225LoadCommand(struct cmdtab const * list, int argc, char **argv)
226{
227  char *name;
228
229  if (argc > 0)
230    name = *argv;
231  else
232    name = "default";
233
234  if (SelectSystem(name, CONFFILE) < 0) {
235    LogPrintf(LogWARN, "%s: not found.\n", name);
236    return -1;
237  }
238  return 0;
239}
240
241int
242SaveCommand(struct cmdtab const *list, int argc, char **argv)
243{
244  LogPrintf(LogWARN, "save command is not implemented (yet).\n");
245  return 1;
246}
247