TDE
/
libtdevnc
mirror of https://mirror.git.trinitydesktop.org/gitea/TDE/libtdevnc
0
0
Fork 0
Code Issues Releases Wiki Activity
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
Branches Tags
${ item.name }
Create tag ${ searchTerm }
Create branch ${ searchTerm }
from 'b03a920cb9'
${ noResults }
libtdevnc/x11vnc/unixpw.c

883 lines
16 KiB
Raw Blame History

/* -- unixpw.c -- */
#ifdef __linux__
/* some conflict with _XOPEN_SOURCE */
extern int grantpt(int);
extern int unlockpt(int);
extern char *ptsname(int);
#endif
#include "x11vnc.h"
#include "scan.h"
#include "cleanup.h"
#include "xinerama.h"
#include <rfb/default8x16.h>
#if LIBVNCSERVER_HAVE_FORK
#if LIBVNCSERVER_HAVE_SYS_WAIT_H
#if LIBVNCSERVER_HAVE_WAITPID
#define UNIXPW
#endif
#endif
#endif
#if LIBVNCSERVER_HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif
#if LIBVNCSERVER_HAVE_TERMIOS_H
#include <termios.h>
#endif
#if 0
#include <sys/stropts.h>
#endif
#if defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__NetBSD__)
#define IS_BSD
#endif
void unixpw_screen(int init);
void unixpw_keystroke(rfbBool down, rfbKeySym keysym, int init);
void unixpw_accept(char *user);
void unixpw_deny(void);
int su_verify(char *user, char *pass);
static int white(void);
static int text_x(void);
static int text_y(void);
static void set_db(void);
static void unixpw_verify(char *user, char *pass);
int unixpw_in_progress = 0;
time_t unixpw_last_try_time = 0;
rfbClientPtr unixpw_client = NULL;
static int in_login = 0, in_passwd = 0, tries = 0;
static int char_row = 0, char_col = 0;
static int char_x = 0, char_y = 0, char_w = 8, char_h = 16;
static int db = 0;
static int white(void) {
static unsigned long black_pix = 0, white_pix = 1, set = 0;
if (depth <= 8 && ! set) {
X_LOCK;
black_pix = BlackPixel(dpy, scr);
white_pix = WhitePixel(dpy, scr);
X_UNLOCK;
set = 1;
}
if (depth <= 8) {
return (int) white_pix;
} else if (depth < 24) {
return 0xffff;
} else {
return 0xffffff;
}
}
static int text_x(void) {
return char_x + char_col * char_w;
}
static int text_y(void) {
return char_y + char_row * char_h;
}
void unixpw_screen(int init) {
#ifndef UNIXPW
rfbLog("-unixpw is not supported on this OS/machine\n");
clean_up_exit(1);
#endif
if (init) {
int x, y;
char log[] = "login: ";
zero_fb(0, 0, dpy_x, dpy_y);
x = nfix(dpy_x / 2 - strlen(log) * char_w, dpy_x);
y = dpy_y / 4;
rfbDrawString(screen, &default8x16Font, x, y, log, white());
char_x = x;
char_y = y;
char_col = strlen(log);
char_row = 0;
}
mark_rect_as_modified(0, 0, dpy_x, dpy_y, 0);
}
#ifdef MAXPATHLEN
static char slave_str[MAXPATHLEN];
#else
static char slave_str[4096];
#endif
char *get_pty_ptmx(int *fd_p) {
char *slave;
int fd = -1, i, ndevs = 4, tmp;
char *devs[] = {
"/dev/ptmx",
"/dev/ptm/clone",
"/dev/ptc",
"/dev/ptmx_bsd"
};
*fd_p = -1;
#if LIBVNCSERVER_HAVE_GRANTPT
for (i=0; i < ndevs; i++) {
#ifdef O_NOCTTY
fd = open(devs[i], O_RDWR|O_NOCTTY);
#else
fd = open(devs[i], O_RDWR);
#endif
if (fd >= 0) {
break;
}
}
if (fd < 0) {
rfbLogPerror("open /dev/ptmx");
return NULL;
}
#if 0
#if defined(FIONBIO)
tmp = 1;
ioctl(fd, FIONBIO, &tmp);
#endif
#endif
#if LIBVNCSERVER_HAVE_SYS_IOCTL_H && defined(TIOCPKT)
tmp = 0;
ioctl(fd, TIOCPKT, (char *) &tmp);
#endif
if (grantpt(fd) != 0) {
rfbLogPerror("grantpt");
close(fd);
return NULL;
}
if (unlockpt(fd) != 0) {
rfbLogPerror("unlockpt");
close(fd);
return NULL;
}
slave = ptsname(fd);
if (! slave) {
rfbLogPerror("ptsname");
close(fd);
return NULL;
}
#if LIBVNCSERVER_HAVE_SYS_IOCTL_H && defined(TIOCFLUSH)
ioctl(fd, TIOCFLUSH, (char *) 0);
#endif
strcpy(slave_str, slave);
*fd_p = fd;
return slave_str;
#else
return NULL;
#endif /* GRANTPT */
}
char *get_pty_loop(int *fd_p) {
char *slave;
char master_str[16];
int fd = -1, i;
char c;
*fd_p = -1;
/* for *BSD loop over /dev/ptyXY */
for (c = 'p'; c <= 'z'; c++) {
for (i=0; i < 16; i++) {
sprintf(master_str, "/dev/pty%c%x", c, i);
#ifdef O_NOCTTY
fd = open(master_str, O_RDWR|O_NOCTTY);
#else
fd = open(master_str, O_RDWR);
#endif
if (fd >= 0) {
break;
}
}
if (fd >= 0) {
break;
}
}
if (fd < 0) {
return NULL;
}
#if LIBVNCSERVER_HAVE_SYS_IOCTL_H && defined(TIOCFLUSH)
ioctl(fd, TIOCFLUSH, (char *) 0);
#endif
sprintf(slave_str, "/dev/tty%c%x", c, i);
*fd_p = fd;
return slave_str;
}
char *get_pty(int *fd_p) {
if (getenv("BSD_PTY")) {
return get_pty_loop(fd_p);
}
#ifdef IS_BSD
return get_pty_loop(fd_p);
#else
#if LIBVNCSERVER_HAVE_GRANTPT
return get_pty_ptmx(fd_p);
#else
return get_pty_loop(fd_p);
#endif
#endif
}
void try_to_be_nobody(void) {
#if LIBVNCSERVER_HAVE_PWD_H
struct passwd *pw;
pw = getpwnam("nobody");
if (pw) {
#if LIBVNCSERVER_HAVE_SETUID
setuid(pw->pw_uid);
#endif
#if LIBVNCSERVER_HAVE_SETEUID
seteuid(pw->pw_uid);
#endif
#if LIBVNCSERVER_HAVE_SETGID
setgid(pw->pw_gid);
#endif
#if LIBVNCSERVER_HAVE_SETEGID
setegid(pw->pw_gid);
#endif
}
#endif /* PWD_H */
}
static int slave_fd = -1;
static void close_alarm (int sig) {
if (slave_fd >= 0) {
close(slave_fd);
}
}
int su_verify(char *user, char *pass) {
#ifndef UNIXPW
return 0;
#else
int i, j, status, fd = -1, sfd, tfd;
char *slave, *bin_true = NULL, *bin_su = NULL;
pid_t pid, pidw;
struct stat sbuf;
static int first = 1;
char instr[16];
if (first) {
set_db();
first = 0;
}
if (unixpw_list) {
char *p, *q, *str = strdup(unixpw_list);
int ok = 0;
p = strtok(str, ",");
while (p) {
if ( (q = strchr(p, ':')) != NULL ) {
*q = '\0'; /* get rid of options. */
}
if (!strcmp(user, p) || !strcmp("*", p)) {
ok = 1;
break;
}
p = strtok(NULL, ",");
}
free(str);
if (! ok) {
return 0;
}
}
if (stat("/bin/su", &sbuf) == 0) {
bin_su = "/bin/su";
} else if (stat("/usr/bin/su", &sbuf) == 0) {
bin_su = "/usr/bin/su";
}
if (bin_su == NULL) {
rfbLogPerror("existence /bin/su");
return 0;
}
if (stat("/bin/true", &sbuf) == 0) {
bin_true = "/bin/true";
} if (stat("/usr/bin/true", &sbuf) == 0) {
bin_true = "/usr/bin/true";
}
if (bin_true == NULL) {
rfbLogPerror("existence /bin/true");
return 0;
}
slave = get_pty(&fd);
if (slave == NULL) {
rfbLogPerror("get_pty failed.");
return 0;
}
if (db) fprintf(stderr, "slave is: %s fd=%d\n", slave, fd);
if (fd < 0) {
rfbLogPerror("get_pty fd < 0");
return 0;
}
fcntl(fd, F_SETFD, 1);
pid = fork();
if (pid < 0) {
rfbLogPerror("fork");
close(fd);
return 0;
}
if (pid == 0) {
int ttyfd;
char tmp[256];
#if LIBVNCSERVER_HAVE_SETSID
if (setsid() == -1) {
perror("setsid");
exit(1);
}
#else
if (setpgrp() == -1) {
perror("setpgrp");
exit(1);
}
#if LIBVNCSERVER_HAVE_SYS_IOCTL_H && defined(TIOCNOTTY)
ttyfd = open("/dev/tty", O_RDWR);
if (ttyfd >= 0) {
(void) ioctl(ttyfd, TIOCNOTTY, (char *) 0);
close(ttyfd);
}
#endif
#endif /* SETSID */
close(0);
close(1);
close(2);
sfd = open(slave, O_RDWR);
if (sfd < 0) {
exit(1);
}
/* sfd should be 0 since we closed 0. */
#ifdef F_SETFL
fcntl (sfd, F_SETFL, O_NONBLOCK);
#endif
if (fcntl(sfd, F_DUPFD, 1) == -1) {
exit(1);
}
if (fcntl(sfd, F_DUPFD, 2) == -1) {
exit(1);
}
unlink("/tmp/isatty");
unlink("/tmp/isastream");
#if LIBVNCSERVER_HAVE_SYS_IOCTL_H
#if 0
if (isastream(sfd)) {
tfd = open("/tmp/isastream", O_CREAT|O_WRONLY, 0600);
close(tfd);
ioctl(sfd, I_PUSH, "ptem");
ioctl(sfd, I_PUSH, "ldterm");
ioctl(sfd, I_PUSH, "ttcompat");
}
#endif
#if 1
#if defined(TIOCSCTTY) && !defined(sun) && !defined(hpux)
ioctl(sfd, TIOCSCTTY, (char *) 0);
#endif
#endif
if (isatty(sfd)) {
char nam[256];
tfd = open("/tmp/isatty", O_CREAT|O_WRONLY, 0600);
close(tfd);
sprintf(nam, "stty -a < %s > /tmp/isatty 2>&1", slave);
system(nam);
}
#endif /* SYS_IOCTL_H */
chdir("/");
try_to_be_nobody();
#if LIBVNCSERVER_HAVE_GETUID
if (getuid() == 0 || geteuid() == 0) {
exit(1);
}
#else
exit(1);
#endif
set_env("LC_ALL", "C");
set_env("LANG", "C");
set_env("SHELL", "/bin/sh");
execlp(bin_su, bin_su, user, "-c", bin_true, (char *) NULL);
exit(1);
}
if (db) fprintf(stderr, "pid: %d\n", pid);
if (db > 3) {
char cmd[32];
usleep( 100 * 1000 );
sprintf(cmd, "ps wu %d", pid);
system(cmd);
sprintf(cmd, "stty -a < %s", slave);
system(cmd);
}
usleep( 500 * 1000 );
/* send the password "early" (i.e. before we drain) */
if (0) {
int k;
for (k = 0; k < strlen(pass); k++) {
write(fd, pass+k, 1);
usleep(100 * 1000);
}
} else {
write(fd, pass, strlen(pass));
}
/*
* set an alarm for blocking read() to close the master
* (presumably terminating the child. we avoid SIGTERM for now)
*/
slave_fd = fd;
signal(SIGALRM, close_alarm);
alarm(10);
/*
* In addition to checking exit code below, we watch for the
* appearance of the string "Password:". BSD does not seem to
* ask for a password trying to su to yourself.
*/
for (i=0; i<16; i++) {
instr[i] = '\0';
}
j = 0;
for (i=0; i < strlen("Password:"); i++) {
char pstr[] = "password:";
char buf[2];
int n;
buf[0] = '\0';
buf[1] = '\0';
n = read(fd, buf, 1);
if (db == 1) fprintf(stderr, "%d ", n, db > 1 ? buf : "");
if (db > 1) fprintf(stderr, "%s", buf);
if (db > 3 && n == 1 && buf[0] == ':') {
char cmd[32];
usleep( 100 * 1000 );
sprintf(cmd, "ps wu %d", pid);
system(cmd);
sprintf(cmd, "stty -a < %s", slave);
system(cmd);
}
if (n == 1) {
if (isspace(buf[0])) {
continue;
}
instr[j++] = tolower(buf[0]);
}
if (n <= 0 || strstr(pstr, instr) != pstr) {
rfbLog("\"Password:\" did not appear: '%s' n=%d\n",
instr, n);
if (db > 3 && n == 1) {
continue;
}
alarm(0);
signal(SIGALRM, SIG_DFL);
slave_fd = -1;
close(fd);
kill(pid, SIGTERM);
waitpid(pid, &status, WNOHANG);
return 0;
}
}
alarm(0);
signal(SIGALRM, SIG_DFL);
usleep( 250 * 1000 );
#if 0
tcdrain(fd);
#endif
signal(SIGALRM, close_alarm);
alarm(15);
/*
* try to drain the output, hopefully never as much as 4096 (motd?)
* if we don't drain we may block at waitpid. If we close(fd), the
* make cause child to die by signal.
*/
for (i = 0; i<4096; i++) {
char buf[2];
int n;
buf[0] = '\0';
buf[1] = '\0';
n = read(fd, buf, 1);
if (db == 1) fprintf(stderr, "%d ", n, db > 1 ? buf : "");
if (db > 1) fprintf(stderr, "%s", buf);
if (n <= 0) {
break;
}
}
if (db) fprintf(stderr, "\n");
alarm(0);
signal(SIGALRM, SIG_DFL);
slave_fd = -1;
pidw = waitpid(pid, &status, 0);
close(fd);
if (pid != pidw) {
return 0;
}
if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
return 1; /* this is the only return of success. */
} else {
return 0;
}
#endif /* UNIXPW */
}
static void unixpw_verify(char *user, char *pass) {
int x, y;
char li[] = "Login incorrect";
char log[] = "login: ";
if (db) fprintf(stderr, "unixpw_verify: '%s' '%s'\n", user, db > 1 ? pass : "********");
rfbLog("unixpw_verify: %s\n", user);
if (su_verify(user, pass)) {
unixpw_accept(user);
return;
}
if (tries < 2) {
char_row++;
char_col = 0;
x = text_x();
y = text_y();
rfbDrawString(screen, &default8x16Font, x, y, li, white());
char_row += 2;
x = text_x();
y = text_y();
rfbDrawString(screen, &default8x16Font, x, y, log, white());
char_col = strlen(log);
mark_rect_as_modified(0, 0, dpy_x, dpy_y, 0);
unixpw_last_try_time = time(0);
unixpw_keystroke(0, 0, 2);
tries++;
} else {
unixpw_deny();
}
}
static void set_db(void) {
if (getenv("DEBUG_UNIXPW")) {
db = atoi(getenv("DEBUG_UNIXPW"));
}
}
void unixpw_keystroke(rfbBool down, rfbKeySym keysym, int init) {
int x, y, i, nmax = 100;
static char user[100], pass[100];
static int u_cnt = 0, p_cnt = 0, first = 1;
char keystr[100];
if (first) {
set_db();
first = 0;
}
if (init) {
in_login = 1;
in_passwd = 0;
if (init == 1) {
tries = 0;
}
u_cnt = 0;
p_cnt = 0;
for (i=0; i<nmax; i++) {
user[i] = '\0';
pass[i] = '\0';
}
return;
}
X_LOCK;
sprintf(keystr, "%s", XKeysymToString(keysym));
X_UNLOCK;
if (db > 2) {
fprintf(stderr, "%s / %s 0x%x %s\n", in_login ? "login":"pass ",
down ? "down":"up ", keysym, keystr);
}
if (keysym == XK_Return || keysym == XK_Linefeed) {
; /* let "up" pass down below for Return case */
} else if (! down) {
return;
}
if (in_login) {
if (keysym == XK_BackSpace || keysym == XK_Delete) {
if (u_cnt > 0) {
user[u_cnt-1] = '\0';
x = text_x();
y = text_y();
zero_fb(x - char_w, y - char_h, x, y);
mark_rect_as_modified(x - char_w, y - char_h,
x, y, 0);
char_col--;
u_cnt--;
}
return;
}
if (keysym == XK_Return || keysym == XK_Linefeed) {
char pw[] = "Password: ";
if (down) {
/*
* require Up so the Return Up is not processed
* by the normal session after login.
*/
return;
}
in_login = 0;
in_passwd = 1;
char_row++;
char_col = 0;
x = text_x();
y = text_y();
rfbDrawString(screen, &default8x16Font, x, y, pw,
white());
char_col = strlen(pw);
mark_rect_as_modified(0, 0, dpy_x, dpy_y, 0);
return;
}
if (keysym <= ' ' || keysym >= 0x7f) {
return;
}
if (u_cnt >= nmax - 1) {
rfbLog("unixpw_deny: username too long\n");
for (i=0; i<nmax; i++) {
user[i] = '\0';
pass[i] = '\0';
}
unixpw_deny();
return;
}
user[u_cnt++] = keystr[0];
x = text_x();
y = text_y();
if (db && db <= 2) fprintf(stderr, "u_cnt: %d %d/%d ks: 0x%x %s\n", u_cnt, x, y, keysym, keystr);
keystr[1] = '\0';
rfbDrawString(screen, &default8x16Font, x, y, keystr, white());
mark_rect_as_modified(x, y-char_h, x+char_w, y, 0);
char_col++;
} else if (in_passwd) {
if (keysym == XK_BackSpace || keysym == XK_Delete) {
if (p_cnt > 0) {
pass[p_cnt-1] = '\0';
p_cnt--;
}
return;
}
if (keysym == XK_Return || keysym == XK_Linefeed) {
if (down) {
/*
* require Up so the Return Up is not processed
* by the normal session after login.
*/
return;
}
in_login = 0;
in_passwd = 0;
pass[p_cnt++] = '\n';
unixpw_verify(user, pass);
for (i=0; i<nmax; i++) {
user[i] = '\0';
pass[i] = '\0';
}
return;
}
if (keysym <= ' ' || keysym >= 0x7f) {
return;
}
if (p_cnt >= nmax - 2) {
rfbLog("unixpw_deny: password too long\n");
for (i=0; i<nmax; i++) {
user[i] = '\0';
pass[i] = '\0';
}
unixpw_deny();
return;
}
pass[p_cnt++] = (char) keysym;
} else {
/* should not happen... clean up a bit. */
u_cnt = 0;
p_cnt = 0;
for (i=0; i<nmax; i++) {
user[i] = '\0';
pass[i] = '\0';
}
}
}
static void apply_opts (char *user) {
char *p, *q, *str, *opts = NULL, *opts_star = NULL;
ClientData *cd = (ClientData *) unixpw_client->clientData;
rfbClientPtr cl = unixpw_client;
int i;
if (! unixpw_list) {
return;
}
str = strdup(unixpw_list);
/* apply any per-user options. */
p = strtok(str, ",");
while (p) {
if ( (q = strchr(p, ':')) != NULL ) {
*q = '\0'; /* get rid of options. */
} else {
p = strtok(NULL, ",");
continue;
}
if (!strcmp(user, p)) {
opts = strdup(q+1);
}
if (!strcmp("*", p)) {
opts_star = strdup(q+1);
}
p = strtok(NULL, ",");
}
free(str);
for (i=0; i < 2; i++) {
char *s = (i == 0) ? opts_star : opts;
if (s == NULL) {
continue;
}
p = strtok(s, "+");
while (p) {
if (!strcmp(p, "viewonly")) {
cl->viewOnly = TRUE;
strncpy(cd->input, "-", CILEN);
} else if (!strcmp(p, "fullaccess")) {
cl->viewOnly = FALSE;
strncpy(cd->input, "-", CILEN);
} else if ((q = strstr(p, "input=")) == p) {
q += strlen("input=");
strncpy(cd->input, q, CILEN);
} else if (!strcmp(p, "deny")) {
cl->viewOnly = TRUE;
unixpw_deny();
break;
}
p = strtok(NULL, "+");
}
free(s);
}
}
void unixpw_accept(char *user) {
apply_opts(user);
unixpw_in_progress = 0;
unixpw_client = NULL;
mark_rect_as_modified(0, 0, dpy_x, dpy_y, 0);
}
void unixpw_deny(void) {
int x, y, i;
char pd[] = "Permission denied.";
char_row += 2;
char_col = 0;
x = char_x + char_col * char_w;
y = char_y + char_row * char_h;
rfbDrawString(screen, &default8x16Font, x, y, pd, white());
mark_rect_as_modified(0, 0, dpy_x, dpy_y, 0);
for (i=0; i<5; i++) {
rfbPE(-1);
usleep(500 * 1000);
}
rfbCloseClient(unixpw_client);
rfbClientConnectionGone(unixpw_client);
rfbPE(-1);
unixpw_in_progress = 0;
unixpw_client = NULL;
copy_screen();
}
View Git Blame Copy Permalink