/* -*-c-*-
*
- * $Id: fw.c,v 1.4 1999/10/10 16:46:12 mdw Exp $
+ * $Id: fw.c,v 1.8 2000/03/23 23:19:19 mdw Exp $
*
* Port forwarding thingy
*
/*----- Revision history --------------------------------------------------*
*
* $Log: fw.c,v $
+ * Revision 1.8 2000/03/23 23:19:19 mdw
+ * Fix changed options in parser table.
+ *
+ * Revision 1.7 2000/03/23 00:37:33 mdw
+ * Add option to change user and group after initialization. Naughtily
+ * reassign short equivalents of --grammar and --options.
+ *
+ * Revision 1.6 1999/12/22 15:44:10 mdw
+ * Make syslog a separate option, and do it better.
+ *
+ * Revision 1.5 1999/10/22 22:47:50 mdw
+ * Grammar changes. Also, don't enable SIGINT if it's currently ignored.
+ *
* Revision 1.4 1999/10/10 16:46:12 mdw
* New resolver to initialize. Also, include options for grammar and
* options references.
#include <unistd.h>
#include <syslog.h>
+#include <grp.h>
+#include <pwd.h>
+
#include <mLib/bres.h>
#include <mLib/dstr.h>
#include <mLib/mdwopt.h>
t = time(0);
tm = localtime(&t);
DENSURE(&d, 64);
- d.len += strftime(d.buf, d.sz, "%Y-%m-%d %H:%M:%S", tm);
- DPUTC(&d, ' ');
+ d.len += strftime(d.buf, d.sz, "%Y-%m-%d %H:%M:%S ", tm);
va_start(ap, fmt);
dstr_vputf(&d, fmt, ap);
va_end(ap);
static void usage(FILE *fp)
{
- pquis(fp, "Usage: $ [-db] [-f file] [config statements...]\n");
+ pquis(fp, "Usage: $ [-dql] [-f file] [config statements...]\n");
}
static void help(FILE *fp)
of the functionality of inetd, netcat, and normal cat. Options available\n\
are:\n\
\n\
--h, --help Display this help message.\n\
--v, --version Display the program's version number.\n\
--u, --usage Display a terse usage summary.\n\
+-h, --help Display this help message.\n\
+-v, --version Display the program's version number.\n\
+-u, --usage Display a terse usage summary.\n\
\n\
--g, --grammar Show a summary of the configuration language.\n\
--o, --options Show a summary of the source and target options.\n\
+-G, --grammar Show a summary of the configuration language.\n\
+-O, --options Show a summary of the source and target options.\n\
\n\
--f, --file=FILE Read configuration from a file.\n\
--d, --daemon Fork into background after initializing.\n\
+-f, --file=FILE Read configuration from a file.\n\
+-q, --quiet Don't emit any logging information.\n\
+-d, --daemon Fork into background after initializing.\n\
+-l, --syslog Send log output to the system logger.\n\
+-s, --setuid=USER Change uid to USER after initializing sources.\n\
+-g, --setgid=GRP Change gid to GRP after initializing sources.\n\
\n\
Configuration may be supplied in one or more configuration files, or on\n\
the command line (or both). If no `-f' option is present, and no\n\
exec.env.[set] var [=] value\n\
\n\
Socket options\n\
- socket.conn [=] number\n\
+ socket.conn [=] number|unlimited|one-shot\n\
socket.logging [=] yes|no\n\
socket.inet.[allow|deny] [from] address [/ address]\n\
socket.unix.fattr.*\n\
sel_state sst;
sig s_term, s_int;
scanner sc;
+ uid_t drop = -1;
+ gid_t dropg = -1;
enum {
f_bogus = 1,
f_file = 2,
+ f_syslog = 4,
f_fork = 8
};
fattr_init(&fattr_global);
scan_create(&sc);
- /* --- Set up some signal handlers --- */
+ /* --- Set up some signal handlers --- *
+ *
+ * Don't enable @SIGINT@ if the caller already disabled it.
+ */
+
+ {
+ struct sigaction sa;
+
+ sig_add(&s_term, SIGTERM, fw_tidy, 0);
+ sigaction(SIGINT, 0, &sa);
+ if (sa.sa_handler != SIG_IGN)
+ sig_add(&s_int, SIGINT, fw_tidy, 0);
+ }
- sig_add(&s_term, SIGTERM, fw_tidy, 0);
- sig_add(&s_int, SIGINT, fw_tidy, 0);
atexit(fw_exit);
/* --- Parse command line options --- */
/* --- Other help options --- */
- { "grammar", 0, 0, 'g' },
- { "options", 0, 0, 'o' },
+ { "grammar", 0, 0, 'G' },
+ { "options", 0, 0, 'O' },
/* --- Other useful arguments --- */
{ "file", OPTF_ARGREQ, 0, 'f' },
{ "fork", 0, 0, 'd' },
{ "daemon", 0, 0, 'd' },
+ { "syslog", 0, 0, 'l' },
+ { "log", 0, 0, 'l' },
{ "quiet", 0, 0, 'q' },
+ { "setuid", OPTF_ARGREQ, 0, 's' },
+ { "uid", OPTF_ARGREQ, 0, 's' },
+ { "setgid", OPTF_ARGREQ, 0, 'g' },
+ { "gid", OPTF_ARGREQ, 0, 'g' },
/* --- Magic terminator --- */
{ 0, 0, 0, 0 }
};
- int i = mdwopt(argc, argv, "+hvu go f:d", opts, 0, 0, 0);
+ int i = mdwopt(argc, argv, "+hvu GO f:dls:g:", opts, 0, 0, 0);
if (i < 0)
break;
usage(stdout);
exit(0);
break;
- case 'g':
+ case 'G':
grammar(stdout);
exit(0);
break;
- case 'o':
+ case 'O':
options(stdout);
exit(0);
break;
case 'd':
f |= f_fork;
break;
+ case 'l':
+ f |= f_syslog;
+ break;
case 'q':
flags |= FW_QUIET;
break;
+ case 's':
+ if (isdigit((unsigned char )optarg[0])) {
+ char *q;
+ drop = strtol(optarg, &q, 0);
+ if (*q)
+ die(1, "bad uid `%s'", optarg);
+ } else {
+ struct passwd *pw = getpwnam(optarg);
+ if (!pw)
+ die(1, "unknown user `%s'", optarg);
+ drop = pw->pw_uid;
+ }
+ break;
+ case 'g':
+ if (isdigit((unsigned char )optarg[0])) {
+ char *q;
+ dropg = strtol(optarg, &q, 0);
+ if (*q)
+ die(1, "bad gid `%s'", optarg);
+ } else {
+ struct group *gr = getgrnam(optarg);
+ if (!gr)
+ die(1, "unknown group `%s'", optarg);
+ dropg = gr->gr_gid;
+ }
+ break;
default:
f |= f_bogus;
break;
conf_parse(&sc);
+ /* --- Drop privileges --- */
+
+#ifdef HAVE_SETGROUPS
+ if ((dropg != -1 && (setgid(dropg) || setgroups(1, &dropg))) ||
+#else
+ if ((dropg != -1 && setgid(dropg)) ||
+#endif
+ (drop != -1 && setuid(drop)))
+ die(1, "couldn't drop privileges: %s", strerror(errno));
+
/* --- Fork into the background --- */
if (f & f_fork) {
kid = fork();
if (kid != 0)
_exit(0);
+ }
+ if (f & f_syslog) {
flags |= FW_SYSLOG;
openlog(QUIS, 0, LOG_DAEMON);
}