+++ /dev/null
-/*
- * libdpkg - Debian packaging suite library routines
- * myopt.c - my very own option parsing
- *
- * Copyright (C) 1994,1995 Ian Jackson <iwj10@cus.cam.ac.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 2,
- * 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, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-#include <string.h>
-
-#include "config.h"
-#include "myopt.h"
-#include "dpkg.h"
-
-void myopt(const char *const **argvp, const struct cmdinfo *cmdinfos) {
- const struct cmdinfo *cip;
- const char *p, *value;
- int l;
-
- ++(*argvp);
- while ((p= **argvp) && *p == '-') {
- ++(*argvp);
- if (!strcmp(p,"--")) break;
- if (*++p == '-') {
- ++p; value=0;
- for (cip= cmdinfos;
- cip->olong || cip->oshort;
- cip++) {
- if (!cip->olong) continue;
- if (!strcmp(p,cip->olong)) break;
- l= strlen(cip->olong);
- if (!strncmp(p,cip->olong,l) &&
- (p[l]== ((cip->takesvalue==2) ? '-' : '='))) { value=p+l+1; break; }
- }
- if (!cip->olong) badusage("unknown option --%s",p);
- if (cip->takesvalue) {
- if (!value) {
- value= *(*argvp)++;
- if (!value) badusage("--%s option takes a value",cip->olong);
- }
- if (cip->call) cip->call(cip,value);
- else *cip->sassignto= value;
- } else {
- if (value) badusage("--%s option does not take a value",cip->olong);
- if (cip->call) cip->call(cip,0);
- else *cip->iassignto= cip->arg;
- }
- } else {
- while (*p) {
- for (cip= cmdinfos; (cip->olong || cip->oshort) && *p != cip->oshort; cip++);
- if (!cip->oshort) badusage("unknown option -%c",*p);
- p++;
- if (cip->takesvalue) {
- if (!*p) {
- value= *(*argvp)++;
- if (!value) badusage("-%c option takes a value",cip->oshort);
- } else {
- value= p; p="";
- if (*value == '=') value++;
- }
- if (cip->call) cip->call(cip,value);
- else *cip->sassignto= value;
- } else {
- if (*p == '=') badusage("-%c option does not take a value",cip->oshort);
- if (cip->call) cip->call(cip,0);
- else *cip->iassignto= cip->arg;
- }
- }
- }
- }
-}
+++ /dev/null
-/**/
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <limits.h>
-#include <unistd.h>
-#include <pwd.h>
-#include <grp.h>
-#include <sys/types.h>
-
-#include "myopt.h"
-
-void usagemessage(void) {
- if (fputs("usage: really [<user-option>] [<group-option> ...] [--]"
- " [<command> [<argument/option> ...]]\n"
- "user-options:\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"
- " -z|--groupsclear only groups specified are to be used\n"
- " -g|--group <groupname> } add this to\n"
- " -G|--gid <gid> } the group list\n",
- stderr) == EOF) { perror("write usage"); exit(-1); }
-}
-
-static const char *opt_user, *opt_useronly;
-static int opt_groupsclear= 0, opt_ngids= 0, opt_uidonly= -1;
-static int opt_gids[512];
-
-static void af_group(const struct cmdinfo *cip, const char *value) {
- struct group *gr;
-
- if (opt_ngids >= sizeof(opt_gids)/sizeof(opt_gids[0]))
- badusage("too many groups specified");
- gr= getgrnam(value);
- if (!gr) { fprintf(stderr,"unknown group `%s'\n",value); exit(-1); }
- opt_gids[opt_ngids++]= gr->gr_gid;
-}
-
-static void af_gid(const struct cmdinfo *cip, const char *value) {
- char *ep;
- unsigned long ul;
-
- if (opt_ngids >= sizeof(opt_gids)/sizeof(opt_gids[0]))
- badusage("too many gids specified");
- ul= strtoul(value,&ep,0);
- if ((*ep) || (uid_t)ul != ul || ul>INT_MAX) badusage("bad gid `%s'",value);
- opt_gids[opt_ngids++]= ul;
-}
-
-static void af_help(const struct cmdinfo *cip, const char *value) {
- usagemessage(); exit(0);
-}
-
-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 },
- { "groupsclear", 'z', 0, &opt_groupsclear, 0, 0, 1 },
- { "group", 'g', 1, 0, 0, af_group },
- { "gid", 'G', 1, 0, 0, af_gid },
- { "help", 'h', 0, 0, 0, af_help },
- { 0, 0 }
-};
-
-#ifdef REALLY_CHECK_FILE
-void checkroot(void) {
- int r;
- r= access(REALLY_CHECK_FILE,W_OK);
- if (r) { perror("sorry"); exit(-1); }
-}
-#endif
-#ifdef REALLY_CHECK_GID
-void checkroot(void) {
- gid_t groups[512];
- int r;
-
- r= getgid(); if (r==REALLY_CHECK_GID) return;
- 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);
-}
-#endif
-#ifdef REALLY_CHECK_NONE
-void checkroot(void) {
-}
-#endif
-
-int main(int argc, const char *const *argv) {
- struct passwd *pw= 0;
- gid_t groups[512];
- int i, j, ngroups, ngroups_in, maingid, orgmaingid, mainuid, orgmainuid, r;
- const char *cp;
-
- checkroot();
- myopt(&argv,cmdinfos);
-
- if (opt_groupsclear && !opt_ngids)
- badusage("-z|--groupsclear must be accompanied by some groups");
- if (opt_user && (opt_useronly || opt_uidonly!=-1))
- badusage("-u|--user may not be used with -i|--useronly or -I|--uidonly");
- if (opt_user && opt_groupsclear)
- badusage("-u|--user may not be used with -z|--groupsclear");
- if (opt_uidonly != -1 && (uid_t)opt_uidonly != opt_uidonly)
- badusage("-I|--uidonly value %d is out of range for a uid",opt_uidonly);
-
- if (!opt_user && !opt_useronly && opt_uidonly==-1 && !opt_ngids) {
- opt_uidonly= 0;
- }
- if (opt_user || opt_useronly) {
- cp= opt_user ? opt_user : opt_useronly;
- pw= getpwnam(cp);
- if (!pw) { fprintf(stderr,"unknown user `%s'\n",cp); exit(-1); }
- opt_uidonly= pw->pw_uid;
- }
- orgmaingid= getgid();
- orgmainuid= getuid();
- if (orgmaingid<0) { perror("getgid failed"); exit(-1); }
- if (opt_user) {
- r= initgroups(opt_user,pw->pw_gid);
- if (r) { perror("initgroups failed"); exit(-1); }
- maingid= pw->pw_gid;
- } else {
- maingid= -1;
- }
- if (opt_groupsclear) {
- ngroups= 0;
- if (opt_ngids > sizeof(groups)/sizeof(groups[0])) {
- fputs("too many groups to set\n",stderr);
- exit(-1);
- }
- } else {
- ngroups= getgroups(0,0);
- if (ngroups<0) { perror("getgroups(0,0) failed"); exit(-1); }
- if (ngroups+opt_ngids > sizeof(groups)/sizeof(groups[0])) {
- fputs("too many groups already set for total to fit\n",stderr);
- exit(-1);
- }
- ngroups= getgroups(ngroups,groups);
- if (ngroups<0) { perror("getgroups failed"); exit(-1); }
- }
- if (opt_ngids) {
- maingid= opt_gids[0];
- }
- if (opt_ngids || opt_groupsclear) {
- ngroups_in= ngroups; ngroups= 0;
- for (i=0; i<ngroups_in; i++) {
- for (j=0; j<ngroups && groups[j] != groups[i]; j++);
- if (j<ngroups) continue;
- groups[ngroups++]= groups[i];
- }
- for (i=0; i<opt_ngids; i++) {
- for (j=0; j<ngroups && groups[j] != opt_gids[i]; j++);
- if (j<ngroups) continue;
- groups[ngroups++]= opt_gids[i];
- }
- r= setgroups(ngroups,groups);
- if (r) { perror("setgroups failed"); exit(-1); }
- }
- if (maingid != -1) {
- r= setgid(maingid); if (r) { perror("setgid failed"); exit(-1); }
- r= setgid(maingid); if (r) { perror("2nd setgid failed"); exit(-1); }
- }
- if (opt_uidonly != -1) {
- mainuid= opt_uidonly;
- } else {
- mainuid= orgmainuid;
- }
- r= setuid(mainuid); if (r) { perror("setuid failed"); exit(-1); }
- r= setuid(mainuid); if (r) { perror("2nd setuid failed"); exit(-1); }
- if (mainuid != 0) {
- r= seteuid(0); if (r>=0) { fputs("could seteuid 0",stderr); exit(-1); }
- if (errno != EPERM) {
- perror("unexpected failure mode for seteuid 0"); exit(-1);
- }
- }
- r= getuid(); if (r<0) { perror("getuid failed"); exit(-1); }
- if (r != mainuid) { fputs("getuid mismatch",stderr); exit(-1); }
- r= geteuid(); if (r<0) { perror("geteuid failed"); exit(-1); }
- if (r != mainuid) { fputs("geteuid mismatch",stderr); exit(-1); }
- if (maingid != -1) {
- for (i=0; i<ngroups && maingid != groups[i]; i++);
- if (i>=ngroups && maingid != orgmaingid) {
- r= setgid(orgmaingid);
- if (r>=0) { fputs("could setgid back",stderr); exit(-1); }
- if (errno != EPERM) {
- perror("unexpected failure mode for setgid back"); exit(-1);
- }
- }
- r= getgid(); if (r<0) { perror("getgid failed"); exit(-1); }
- if (r != maingid) { fputs("getgid mismatch",stderr); exit(-1); }
- r= getegid(); if (r<0) { perror("getegid failed"); exit(-1); }
- if (r != maingid) { fputs("getegid mismatch",stderr); exit(-1); }
- }
- if (!*argv) {
- cp= getenv("SHELL");
- if (!cp) cp= "sh";
- execlp(cp,cp,"-i",(const char*)0);
- } else {
- execvp(argv[0],(char**)argv);
- }
- perror("exec failed");
- exit(-1);
-}
~ian / chiark-utils.git / commitdiff