-/**/
+/*
+ * really.c - program for gaining privilege
+ *
+ * Copyright (C) 1992-3 Ian Jackson <ian@davenant.greenend.org.uk>
+ *
+ * This 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 3,
+ * or (at your option) any later version.
+ *
+ * This 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 file; if not, consult the Free Software
+ * Foundation's website at www.fsf.org, or the GNU Project website at
+ * www.gnu.org.
+ */
#include <stdio.h>
#include <stdlib.h>
#include "myopt.h"
void usagemessage(void) {
- if (fputs("usage: really [<user-option>] [<group-option> ...] [--]"
+ if (fputs("usage: really [<really-option> ...] [--]"
" [<command> [<argument/option> ...]]\n"
- "user-options:\n"
+ "really-options specifying the user:\n"
" if no options given, set the uid to 0;\n"
" -u|--user <username> also sets their default group list\n"
" -i|--useronly <username> } set the uid\n"
" -I|--uidonly <uid> } but inherits the group list\n"
- "group-options:\n"
+ "really-options specifying the group:\n"
" -z|--groupsclear only groups specified are to be used\n"
" -g|--group <groupname> } add this to\n"
- " -G|--gid <gid> } the group list\n",
+ " -G|--gid <gid> } the group list\n"
+ "other really-options:\n"
+ " -h|--help display this message\n"
+ " -R|--chroot <dir> chroot (but *not* chdir - danger!)\n",
stderr) == EOF) { perror("write usage"); exit(-1); }
}
-static const char *opt_user, *opt_useronly;
+static const char *opt_user, *opt_useronly, *opt_chroot;
static int opt_groupsclear= 0, opt_ngids= 0, opt_uidonly= -1;
static int opt_gids[512];
+static void af_uidonly(const struct cmdinfo *cip, const char *value) {
+ unsigned long ul;
+ char *ep;
+
+ ul= strtoul(value,&ep,10);
+ if (*ep) { fprintf(stderr,"bad uid `%s'\n",value); exit(-1); }
+ opt_uidonly= ul;
+}
+
static void af_group(const struct cmdinfo *cip, const char *value) {
struct group *gr;
static const struct cmdinfo cmdinfos[]= {
{ "user", 'u', 1, 0, &opt_user, 0, },
{ "useronly", 'i', 1, 0, &opt_useronly, 0 },
- { "uidonly", 'I', 1, &opt_uidonly, 0, 0 },
+ { "uidonly", 'I', 1, 0, 0, af_uidonly },
{ "groupsclear", 'z', 0, &opt_groupsclear, 0, 0, 1 },
{ "group", 'g', 1, 0, 0, af_group },
{ "gid", 'G', 1, 0, 0, af_gid },
+ { "chroot", 'R', 1, 0, &opt_chroot, 0 },
{ "help", 'h', 0, 0, 0, af_help },
{ 0, 0 }
};
#ifdef REALLY_CHECK_FILE
-static void checkroot(void) {
+static int checkroot(void) {
int r;
r= access(REALLY_CHECK_FILE,W_OK);
- if (r) { perror("sorry"); exit(-1); }
+ if (r) return -1;
+ return 0;
}
#endif
#ifdef REALLY_CHECK_GID
-static void checkroot(void) {
+static int checkroot(void) {
gid_t groups[512];
- int r;
+ int r, i;
- r= getgid(); if (r==REALLY_CHECK_GID) return;
+ r= getgid(); if (r==REALLY_CHECK_GID) return 0;
if (r<0) { perror("getgid check"); exit(-1); }
r= getgroups(sizeof(groups)/sizeof(groups[0]),groups);
if (r<0) { perror("getgroups check"); exit(-1); }
for (i=0; i<r; i++)
- if (groups[i] == REALLY_CHECK_GID) return;
- fputs("sorry\n",stderr); exit(-1);
+ if (groups[i] == REALLY_CHECK_GID) return 0;
+ return -1;
}
#endif
#ifdef REALLY_CHECK_NONE
-static void checkroot(void) {
+static int checkroot(void) {
+ return 0;
}
#endif
int i, j, ngroups, ngroups_in, maingid, orgmaingid, mainuid, orgmainuid, r;
const char *cp;
- checkroot();
+ orgmainuid= getuid();
+ if (orgmainuid && checkroot()) { perror("sorry"); exit(-1); }
myopt(&argv,cmdinfos);
if (opt_groupsclear && !opt_ngids)
if (!pw) { fprintf(stderr,"unknown user `%s'\n",cp); exit(-1); }
opt_uidonly= pw->pw_uid;
}
+ if (opt_chroot) {
+ if (chroot(opt_chroot)) { perror("chroot failed"); exit(-1); }
+ }
orgmaingid= getgid();
- orgmainuid= getuid();
if (orgmaingid<0) { perror("getgid failed"); exit(-1); }
if (opt_user) {
r= initgroups(opt_user,pw->pw_gid);