#include <sys/resource.h>
#include <syslog.h>
-#ifdef CONFIG_SELINUX
+#if ENABLE_SELINUX
#include <selinux/selinux.h> /* for is_selinux_enabled() */
#include <selinux/get_context_list.h> /* for get_default_context() */
#include <selinux/flask.h> /* for security class definitions */
TTYNAME_SIZE = 32,
};
-static char full_tty[TTYNAME_SIZE];
-static char* short_tty = full_tty;
+static char* short_tty;
#if ENABLE_FEATURE_UTMP
/* vv Taken from tinylogin utmp.c vv */
* command line flags.
*/
-static struct utmp utent;
-
-static void read_or_build_utent(int picky)
+static void read_or_build_utent(struct utmp *utptr, int picky)
{
struct utmp *ut;
pid_t pid = getpid();
/* If there is one, just use it, otherwise create a new one. */
if (ut) {
- utent = *ut;
+ *utptr = *ut;
} else {
if (picky)
bb_error_msg_and_die("no utmp entry found");
- memset(&utent, 0, sizeof(utent));
- utent.ut_type = LOGIN_PROCESS;
- utent.ut_pid = pid;
- strncpy(utent.ut_line, short_tty, sizeof(utent.ut_line));
+ memset(utptr, 0, sizeof(*utptr));
+ utptr->ut_type = LOGIN_PROCESS;
+ utptr->ut_pid = pid;
+ strncpy(utptr->ut_line, short_tty, sizeof(utptr->ut_line));
/* This one is only 4 chars wide. Try to fit something
* remotely meaningful by skipping "tty"... */
- strncpy(utent.ut_id, short_tty + 3, sizeof(utent.ut_id));
- strncpy(utent.ut_user, "LOGIN", sizeof(utent.ut_user));
- utent.ut_time = time(NULL);
+ strncpy(utptr->ut_id, short_tty + 3, sizeof(utptr->ut_id));
+ strncpy(utptr->ut_user, "LOGIN", sizeof(utptr->ut_user));
+ utptr->ut_time = time(NULL);
}
if (!picky) /* root login */
- memset(utent.ut_host, 0, sizeof(utent.ut_host));
+ memset(utptr->ut_host, 0, sizeof(utptr->ut_host));
}
/*
* write_utent changes the type of the current utmp entry to
* USER_PROCESS. the wtmp file will be updated as well.
*/
-static void write_utent(const char *username)
+static void write_utent(struct utmp *utptr, const char *username)
{
- utent.ut_type = USER_PROCESS;
- strncpy(utent.ut_user, username, sizeof(utent.ut_user));
- utent.ut_time = time(NULL);
+ utptr->ut_type = USER_PROCESS;
+ strncpy(utptr->ut_user, username, sizeof(utptr->ut_user));
+ utptr->ut_time = time(NULL);
/* other fields already filled in by read_or_build_utent above */
setutent();
- pututline(&utent);
+ pututline(utptr);
endutent();
#if ENABLE_FEATURE_WTMP
if (access(bb_path_wtmp_file, R_OK|W_OK) == -1) {
close(creat(bb_path_wtmp_file, 0664));
}
- updwtmp(bb_path_wtmp_file, &utent);
+ updwtmp(bb_path_wtmp_file, utptr);
#endif
}
#else /* !ENABLE_FEATURE_UTMP */
-static inline void read_or_build_utent(int ATTRIBUTE_UNUSED picky) {}
-static inline void write_utent(const char ATTRIBUTE_UNUSED *username) {}
+#define read_or_build_utent(utptr, picky) ((void)0)
+#define write_utent(utptr, username) ((void)0)
#endif /* !ENABLE_FEATURE_UTMP */
static void die_if_nologin_and_non_root(int amroot)
return 1;
}
while (fgets(buf, sizeof(buf)-1, fp)) {
- for(i = strlen(buf)-1; i>=0; --i) {
+ for (i = strlen(buf)-1; i>=0; --i) {
if (!isspace(buf[i]))
break;
}
}
}
-static void nonblock(int fd)
-{
- fcntl(fd, F_SETFL, O_NONBLOCK | fcntl(fd, F_GETFL));
-}
-
static void alarm_handler(int sig ATTRIBUTE_UNUSED)
{
/* This is the escape hatch! Poor serial line users and the like
* arrive here when their connection is broken.
* We don't want to block here */
- nonblock(1);
- nonblock(2);
+ ndelay_on(1);
+ ndelay_on(2);
bb_info_msg("\r\nLogin timed out after %d seconds\r", TIMEOUT);
exit(EXIT_SUCCESS);
}
+int login_main(int argc, char **argv);
int login_main(int argc, char **argv)
{
enum {
struct passwd *pw;
char *opt_host = NULL;
char *opt_user = NULL;
+ char full_tty[TTYNAME_SIZE];
USE_SELINUX(security_context_t user_sid = NULL;)
+ USE_FEATURE_UTMP(struct utmp utent;)
+ short_tty = full_tty;
username[0] = '\0';
amroot = (getuid() == 0);
signal(SIGALRM, alarm_handler);
short_tty = full_tty + 5;
}
- read_or_build_utent(!amroot);
+ read_or_build_utent(&utent, !amroot);
if (opt_host) {
USE_FEATURE_UTMP(
safe_strncpy(utent.ut_host, opt_host, sizeof(utent.ut_host));
)
- snprintf(fromhost, sizeof(fromhost)-1, " on `%.100s' from "
- "`%.200s'", short_tty, opt_host);
- }
- else
- snprintf(fromhost, sizeof(fromhost)-1, " on `%.100s'", short_tty);
+ snprintf(fromhost, sizeof(fromhost)-1, " on '%.100s' from "
+ "'%.200s'", short_tty, opt_host);
+ } else
+ snprintf(fromhost, sizeof(fromhost)-1, " on '%.100s'", short_tty);
bb_setpgrp;
bb_do_delay(FAIL_DELAY);
puts("Login incorrect");
if (++count == 3) {
- syslog(LOG_WARNING, "invalid password for `%s'%s",
+ syslog(LOG_WARNING, "invalid password for '%s'%s",
username, fromhost);
return EXIT_FAILURE;
}
alarm(0);
die_if_nologin_and_non_root(pw->pw_uid == 0);
- write_utent(username);
+ write_utent(&utent, username);
#ifdef CONFIG_SELINUX
if (is_selinux_enabled()) {
security_context_t old_tty_sid, new_tty_sid;
if (get_default_context(username, NULL, &user_sid)) {
- bb_error_msg_and_die("unable to get SID for %s",
+ bb_error_msg_and_die("cannot get SID for %s",
username);
}
if (getfilecon(full_tty, &old_tty_sid) < 0) {
- bb_perror_msg_and_die("getfilecon(%.100s) failed",
+ bb_perror_msg_and_die("getfilecon(%s) failed",
full_tty);
}
if (security_compute_relabel(user_sid, old_tty_sid,
SECCLASS_CHR_FILE, &new_tty_sid) != 0) {
- bb_perror_msg_and_die("security_change_sid(%.100s) failed",
+ bb_perror_msg_and_die("security_change_sid(%s) failed",
full_tty);
}
if (setfilecon(full_tty, new_tty_sid) != 0) {
- bb_perror_msg_and_die("chsid(%.100s, %s) failed",
+ bb_perror_msg_and_die("chsid(%s, %s) failed",
full_tty, new_tty_sid);
}
}
fchown(0, pw->pw_uid, pw->pw_gid);
fchmod(0, 0600);
- /* TODO: be nommu-friendly, use spawn? */
if (ENABLE_LOGIN_SCRIPTS) {
- char *script = getenv("LOGIN_PRE_SUID_SCRIPT");
- if (script) {
- char *t_argv[2] = { script, NULL };
- switch (fork()) {
- case -1: break;
- case 0: /* child */
- xchdir("/");
- setenv("LOGIN_TTY", full_tty, 1);
- setenv("LOGIN_USER", pw->pw_name, 1);
- setenv("LOGIN_UID", utoa(pw->pw_uid), 1);
- setenv("LOGIN_GID", utoa(pw->pw_gid), 1);
- setenv("LOGIN_SHELL", pw->pw_shell, 1);
- execvp(script, t_argv);
- exit(1);
- default: /* parent */
- wait(NULL);
- }
+ char *t_argv[2];
+
+ t_argv[0] = getenv("LOGIN_PRE_SUID_SCRIPT");
+ if (t_argv[0]) {
+ t_argv[1] = NULL;
+ setenv("LOGIN_TTY", full_tty, 1);
+ setenv("LOGIN_USER", pw->pw_name, 1);
+ setenv("LOGIN_UID", utoa(pw->pw_uid), 1);
+ setenv("LOGIN_GID", utoa(pw->pw_gid), 1);
+ setenv("LOGIN_SHELL", pw->pw_shell, 1);
+ xspawn(argv); /* NOMMU-friendly */
+ unsetenv("LOGIN_TTY");
+ unsetenv("LOGIN_USER");
+ unsetenv("LOGIN_UID");
+ unsetenv("LOGIN_GID");
+ unsetenv("LOGIN_SHELL");
+ wait(NULL);
}
}
// /* TIOCSCTTY: steal tty from other process group */
// if (ioctl(0, TIOCSCTTY, 1)) error_msg...
- signal(SIGALRM, SIG_DFL); /* set signals to defaults */
+ /* set signals to defaults */
+ signal(SIGALRM, SIG_DFL);
+ /* Is this correct? This way user can ctrl-c out of /etc/profile,
+ * potentially creating security breach (tested with bash 3.0).
+ * But without this, bash 3.0 will not enable ctrl-c either.
+ * Maybe bash is buggy?
+ * Need to find out what standards say about /bin/login -
+ * should it leave SIGINT etc enabled or disabled? */
signal(SIGINT, SIG_DFL);
run_shell(tmp, 1, 0, 0); /* exec the shell finally */
projects / oweals / busybox.git / blobdiff