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Remove support for rlogind in login(1), that is, remove the '-r' flag

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The "quick hack" finally disappeared.  Probably nobody noticed.  ;)
(See the changes in <configure.ac> for the context of this pun.)

Probably everybody uses SSH these days for remote login.  Let's remove
this insecure method.

Closes: <https://github.com/shadow-maint/shadow/issues/992>
Reviewed-by: dkwo <nicolopiazzalunga@gmail.com>
Reviewed-by: Iker Pedrosa <ipedrosa@redhat.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Michael Vetter <jubalh@iodoru.org>
Cc: Sam James <sam@gentoo.org>
Cc: Benedikt Brinkmann <datacobra@thinkbot.de>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
This commit is contained in:
Alejandro Colomar
2024-05-18 01:57:40 +02:00
committed by Serge Hallyn
parent df59088641
commit ca046af5d9
8 changed files with 12 additions and 288 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/login.c
+12 -71
View File
@@ -85,11 +85,6 @@ static struct lastlog ll;
static bool pflg = false;
static bool fflg = false;
#ifdef RLOGIN
static bool rflg = false;
#else /* RLOGIN */
#define rflg false
#endif /* !RLOGIN */
static bool hflg = false;
static bool preauth_flag = false;
@@ -134,7 +129,6 @@ static void exit_handler (int);
* usage - print login command usage and exit
*
* login [ name ]
* login -r hostname (for rlogind)
* login -h hostname (for telnetd, etc.)
* login -f name (for pre-authenticated login: datakit, xterm, etc.)
*/
@@ -145,9 +139,6 @@ static void usage (void)
exit (1);
}
fprintf (stderr, _(" %s [-p] [-h host] [-f name]\n"), Prog);
#ifdef RLOGIN
fprintf (stderr, _(" %s [-p] -r host\n"), Prog);
#endif /* RLOGIN */
exit (1);
}
@@ -271,7 +262,7 @@ static void process_flags (int argc, char *const *argv)
/*
* Check the flags for proper form. Every argument starting with
* "-" must be exactly two characters long. This closes all the
* clever rlogin, telnet, and getty holes.
* clever telnet, and getty holes.
*/
for (arg = 1; arg < argc; arg++) {
if (argv[arg][0] == '-' && strlen (argv[arg]) > 2) {
@@ -298,13 +289,6 @@ static void process_flags (int argc, char *const *argv)
hostname = optarg;
reason = PW_TELNET;
break;
#ifdef RLOGIN
case 'r':
rflg = true;
hostname = optarg;
reason = PW_RLOGIN;
break;
#endif /* RLOGIN */
case 'p':
pflg = true;
break;
@@ -313,21 +297,11 @@ static void process_flags (int argc, char *const *argv)
}
}
#ifdef RLOGIN
/*
* Neither -h nor -f should be combined with -r.
*/
if (rflg && (hflg || fflg)) {
usage ();
}
#endif /* RLOGIN */
/*
* Allow authentication bypass only if real UID is zero.
*/
if ((rflg || fflg || hflg) && !amroot) {
if ((fflg || hflg) && !amroot) {
fprintf (stderr, _("%s: Permission denied.\n"), Prog);
exit (1);
}
@@ -342,11 +316,6 @@ static void process_flags (int argc, char *const *argv)
++optind;
}
#ifdef RLOGIN
if (rflg && (NULL != username)) {
usage ();
}
#endif /* RLOGIN */
if (fflg && (NULL == username)) {
usage ();
}
@@ -474,7 +443,6 @@ static /*@observer@*/const char *get_failent_user (/*@returned@*/const char *use
* the flags which login supports are
*
* -p - preserve the environment
* -r - perform autologin protocol for rlogin
* -f - do not perform authentication, user is preauthenticated
* -h - the name of the remote host
*/
@@ -505,9 +473,6 @@ int main (int argc, char **argv)
# if defined(ENABLE_LASTLOG)
char ptime[80];
# endif
#endif
#if defined(RLOGIN)
char term[128] = "";
#endif
/*
@@ -559,7 +524,7 @@ int main (int argc, char **argv)
is_console = console (tty);
#endif
if (rflg || hflg) {
if (hflg) {
/*
* Add remote hostname to the environment. I think
* (not sure) I saw it once on Irix. --marekm
@@ -572,23 +537,6 @@ int main (int argc, char **argv)
if (hflg) {
reason = PW_RLOGIN;
}
#ifdef RLOGIN
if (rflg) {
size_t max_size;
max_size = login_name_max_size();
assert (NULL == username);
username = XMALLOC(max_size, char);
username[max_size - 1] = '\0';
if (do_rlogin(hostname, username, max_size, term, sizeof(term)))
{
preauth_flag = true;
} else {
free (username);
username = NULL;
}
}
#endif /* RLOGIN */
OPENLOG (Prog);
@@ -623,18 +571,11 @@ int main (int argc, char **argv)
}
}
#ifdef RLOGIN
if (term[0] != '\0') {
addenv ("TERM", term);
} else
#endif /* RLOGIN */
{
/* preserve TERM from getty */
if (!pflg) {
tmp = getenv ("TERM");
if (NULL != tmp) {
addenv ("TERM", tmp);
}
/* preserve TERM from getty */
if (!pflg) {
tmp = getenv ("TERM");
if (NULL != tmp) {
addenv ("TERM", tmp);
}
}
@@ -644,7 +585,7 @@ int main (int argc, char **argv)
set_env (argc - optind, &argv[optind]);
}
if (rflg || hflg) {
if (hflg) {
cp = hostname;
} else if ((host != NULL) && (host[0] != '\0')) {
cp = host;
@@ -954,7 +895,7 @@ int main (int argc, char **argv)
}
/*
* The -r and -f flags provide a name which has already
* The -f flag provides a name which has already
* been authenticated by some server.
*/
if (preauth_flag) {
@@ -1043,8 +984,8 @@ int main (int argc, char **argv)
(void) puts (_("Login incorrect"));
/* allow only one attempt with -r or -f */
if (rflg || fflg || (retries <= 0)) {
/* allow only one attempt with -f */
if (fflg || (retries <= 0)) {
closelog ();
exit (1);
}