mirror of
https://git.tartarus.org/simon/putty.git
synced 2025-01-10 01:48:00 +00:00
470 lines
9.8 KiB
C
470 lines
9.8 KiB
C
#define _XOPEN_SOURCE
|
|
#define _XOPEN_SOURCE_EXTENDED
|
|
#include <features.h>
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
#include <signal.h>
|
|
#include <fcntl.h>
|
|
#include <termios.h>
|
|
#include <grp.h>
|
|
#include <utmp.h>
|
|
#include <pwd.h>
|
|
#include <time.h>
|
|
#include <sys/types.h>
|
|
#include <sys/wait.h>
|
|
#include <sys/ioctl.h>
|
|
|
|
#include "putty.h"
|
|
|
|
#ifndef FALSE
|
|
#define FALSE 0
|
|
#endif
|
|
#ifndef TRUE
|
|
#define TRUE 1
|
|
#endif
|
|
|
|
#ifndef UTMP_FILE
|
|
#define UTMP_FILE "/var/run/utmp"
|
|
#endif
|
|
#ifndef WTMP_FILE
|
|
#define WTMP_FILE "/var/log/wtmp"
|
|
#endif
|
|
#ifndef LASTLOG_FILE
|
|
#ifdef _PATH_LASTLOG
|
|
#define LASTLOG_FILE _PATH_LASTLOG
|
|
#else
|
|
#define LASTLOG_FILE "/var/log/lastlog"
|
|
#endif
|
|
#endif
|
|
|
|
/*
|
|
* Set up a default for vaguely sane systems. The idea is that if
|
|
* OMIT_UTMP is not defined, then at least one of the symbols which
|
|
* enable particular forms of utmp processing should be, if only so
|
|
* that a link error can warn you that you should have defined
|
|
* OMIT_UTMP if you didn't want any. Currently HAVE_PUTUTLINE is
|
|
* the only such symbol.
|
|
*/
|
|
#ifndef OMIT_UTMP
|
|
#if !defined HAVE_PUTUTLINE
|
|
#define HAVE_PUTUTLINE
|
|
#endif
|
|
#endif
|
|
|
|
int pty_master_fd;
|
|
static int pty_stamped_utmp = 0;
|
|
static int pty_child_pid;
|
|
static sig_atomic_t pty_child_dead;
|
|
#ifndef OMIT_UTMP
|
|
static struct utmp utmp_entry;
|
|
#endif
|
|
char **pty_argv;
|
|
|
|
int pty_child_is_dead(void)
|
|
{
|
|
return pty_child_dead;
|
|
}
|
|
|
|
static void pty_size(void);
|
|
|
|
static void setup_utmp(char *ttyname)
|
|
{
|
|
#ifndef OMIT_UTMP
|
|
#ifdef HAVE_LASTLOG
|
|
struct lastlog lastlog_entry;
|
|
FILE *lastlog;
|
|
#endif
|
|
struct passwd *pw;
|
|
char *location;
|
|
FILE *wtmp;
|
|
|
|
if (!cfg.stamp_utmp)
|
|
return;
|
|
|
|
pw = getpwuid(getuid());
|
|
location = get_x_display();
|
|
memset(&utmp_entry, 0, sizeof(utmp_entry));
|
|
utmp_entry.ut_type = USER_PROCESS;
|
|
utmp_entry.ut_pid = getpid();
|
|
strncpy(utmp_entry.ut_line, ttyname+5, lenof(utmp_entry.ut_line));
|
|
strncpy(utmp_entry.ut_id, ttyname+8, lenof(utmp_entry.ut_id));
|
|
strncpy(utmp_entry.ut_user, pw->pw_name, lenof(utmp_entry.ut_user));
|
|
strncpy(utmp_entry.ut_host, location, lenof(utmp_entry.ut_host));
|
|
time(&utmp_entry.ut_time);
|
|
|
|
#if defined HAVE_PUTUTLINE
|
|
utmpname(UTMP_FILE);
|
|
setutent();
|
|
pututline(&utmp_entry);
|
|
endutent();
|
|
#endif
|
|
|
|
if ((wtmp = fopen(WTMP_FILE, "a")) != NULL) {
|
|
fwrite(&utmp_entry, 1, sizeof(utmp_entry), wtmp);
|
|
fclose(wtmp);
|
|
}
|
|
|
|
#ifdef HAVE_LASTLOG
|
|
memset(&lastlog_entry, 0, sizeof(lastlog_entry));
|
|
strncpy(lastlog_entry.ll_line, ttyname+5, lenof(lastlog_entry.ll_line));
|
|
strncpy(lastlog_entry.ll_host, location, lenof(lastlog_entry.ll_host));
|
|
time(&lastlog_entry.ll_time);
|
|
if ((lastlog = fopen(LASTLOG_FILE, "r+")) != NULL) {
|
|
fseek(lastlog, sizeof(lastlog_entry) * getuid(), SEEK_SET);
|
|
fwrite(&lastlog_entry, 1, sizeof(lastlog_entry), lastlog);
|
|
fclose(lastlog);
|
|
}
|
|
#endif
|
|
|
|
pty_stamped_utmp = 1;
|
|
|
|
#endif
|
|
}
|
|
|
|
static void cleanup_utmp(void)
|
|
{
|
|
#ifndef OMIT_UTMP
|
|
FILE *wtmp;
|
|
|
|
if (!cfg.stamp_utmp || !pty_stamped_utmp)
|
|
return;
|
|
|
|
utmp_entry.ut_type = DEAD_PROCESS;
|
|
memset(utmp_entry.ut_user, 0, lenof(utmp_entry.ut_user));
|
|
time(&utmp_entry.ut_time);
|
|
|
|
if ((wtmp = fopen(WTMP_FILE, "a")) != NULL) {
|
|
fwrite(&utmp_entry, 1, sizeof(utmp_entry), wtmp);
|
|
fclose(wtmp);
|
|
}
|
|
|
|
memset(utmp_entry.ut_line, 0, lenof(utmp_entry.ut_line));
|
|
utmp_entry.ut_time = 0;
|
|
|
|
#if defined HAVE_PUTUTLINE
|
|
utmpname(UTMP_FILE);
|
|
setutent();
|
|
pututline(&utmp_entry);
|
|
endutent();
|
|
#endif
|
|
|
|
pty_stamped_utmp = 0; /* ensure we never double-cleanup */
|
|
#endif
|
|
}
|
|
|
|
static void sigchld_handler(int signum)
|
|
{
|
|
pid_t pid;
|
|
int status;
|
|
pid = waitpid(-1, &status, WNOHANG);
|
|
if (pid == pty_child_pid && (WIFEXITED(status) || WIFSIGNALED(status)))
|
|
pty_child_dead = TRUE;
|
|
}
|
|
|
|
static void fatal_sig_handler(int signum)
|
|
{
|
|
signal(signum, SIG_DFL);
|
|
cleanup_utmp();
|
|
setuid(getuid());
|
|
raise(signum);
|
|
}
|
|
|
|
/*
|
|
* Called to set up the pty.
|
|
*
|
|
* Returns an error message, or NULL on success.
|
|
*
|
|
* Also places the canonical host name into `realhost'. It must be
|
|
* freed by the caller.
|
|
*/
|
|
static char *pty_init(char *host, int port, char **realhost, int nodelay)
|
|
{
|
|
int slavefd;
|
|
char name[FILENAME_MAX];
|
|
pid_t pid, pgrp;
|
|
|
|
#ifdef BSD_PTYS
|
|
{
|
|
const char chars1[] = "pqrstuvwxyz";
|
|
const char chars2[] = "0123456789abcdef";
|
|
const char *p1, *p2;
|
|
char master_name[20];
|
|
|
|
for (p1 = chars1; *p1; p1++)
|
|
for (p2 = chars2; *p2; p2++) {
|
|
sprintf(master_name, "/dev/pty%c%c", *p1, *p2);
|
|
pty_master_fd = open(master_name, O_RDWR);
|
|
if (pty_master_fd >= 0) {
|
|
if (geteuid() == 0 ||
|
|
access(master_name, R_OK | W_OK) == 0)
|
|
goto got_one;
|
|
close(pty_master_fd);
|
|
}
|
|
}
|
|
|
|
/* If we get here, we couldn't get a tty at all. */
|
|
fprintf(stderr, "pterm: unable to open a pseudo-terminal device\n");
|
|
exit(1);
|
|
|
|
got_one:
|
|
strcpy(name, master_name);
|
|
name[5] = 't'; /* /dev/ptyXX -> /dev/ttyXX */
|
|
}
|
|
#else
|
|
pty_master_fd = open("/dev/ptmx", O_RDWR);
|
|
|
|
if (pty_master_fd < 0) {
|
|
perror("/dev/ptmx: open");
|
|
exit(1);
|
|
}
|
|
|
|
if (grantpt(pty_master_fd) < 0) {
|
|
perror("grantpt");
|
|
exit(1);
|
|
}
|
|
|
|
if (unlockpt(pty_master_fd) < 0) {
|
|
perror("unlockpt");
|
|
exit(1);
|
|
}
|
|
|
|
name[FILENAME_MAX-1] = '\0';
|
|
strncpy(name, ptsname(pty_master_fd), FILENAME_MAX-1);
|
|
#endif
|
|
|
|
/*
|
|
* Set the backspace character to be whichever of ^H and ^? is
|
|
* specified by bksp_is_delete.
|
|
*/
|
|
{
|
|
struct termios attrs;
|
|
tcgetattr(pty_master_fd, &attrs);
|
|
attrs.c_cc[VERASE] = cfg.bksp_is_delete ? '\177' : '\010';
|
|
tcsetattr(pty_master_fd, TCSANOW, &attrs);
|
|
}
|
|
|
|
/*
|
|
* Trap as many fatal signals as we can in the hope of having
|
|
* the best chance to clean up utmp before termination.
|
|
*/
|
|
signal(SIGHUP, fatal_sig_handler);
|
|
signal(SIGINT, fatal_sig_handler);
|
|
signal(SIGQUIT, fatal_sig_handler);
|
|
signal(SIGILL, fatal_sig_handler);
|
|
signal(SIGABRT, fatal_sig_handler);
|
|
signal(SIGFPE, fatal_sig_handler);
|
|
signal(SIGPIPE, fatal_sig_handler);
|
|
signal(SIGALRM, fatal_sig_handler);
|
|
signal(SIGTERM, fatal_sig_handler);
|
|
signal(SIGSEGV, fatal_sig_handler);
|
|
signal(SIGUSR1, fatal_sig_handler);
|
|
signal(SIGUSR2, fatal_sig_handler);
|
|
#ifdef SIGBUS
|
|
signal(SIGBUS, fatal_sig_handler);
|
|
#endif
|
|
#ifdef SIGPOLL
|
|
signal(SIGPOLL, fatal_sig_handler);
|
|
#endif
|
|
#ifdef SIGPROF
|
|
signal(SIGPROF, fatal_sig_handler);
|
|
#endif
|
|
#ifdef SIGSYS
|
|
signal(SIGSYS, fatal_sig_handler);
|
|
#endif
|
|
#ifdef SIGTRAP
|
|
signal(SIGTRAP, fatal_sig_handler);
|
|
#endif
|
|
#ifdef SIGVTALRM
|
|
signal(SIGVTALRM, fatal_sig_handler);
|
|
#endif
|
|
#ifdef SIGXCPU
|
|
signal(SIGXCPU, fatal_sig_handler);
|
|
#endif
|
|
#ifdef SIGXFSZ
|
|
signal(SIGXFSZ, fatal_sig_handler);
|
|
#endif
|
|
#ifdef SIGIO
|
|
signal(SIGIO, fatal_sig_handler);
|
|
#endif
|
|
/* Also clean up utmp on normal exit. */
|
|
atexit(cleanup_utmp);
|
|
setup_utmp(name);
|
|
|
|
/*
|
|
* Fork and execute the command.
|
|
*/
|
|
pid = fork();
|
|
if (pid < 0) {
|
|
perror("fork");
|
|
exit(1);
|
|
}
|
|
|
|
if (pid == 0) {
|
|
int i;
|
|
/*
|
|
* We are the child.
|
|
*/
|
|
|
|
slavefd = open(name, O_RDWR);
|
|
if (slavefd < 0) {
|
|
perror("slave pty: open");
|
|
exit(1);
|
|
}
|
|
|
|
#ifdef BSD_PTYS
|
|
/* We need to chown/chmod the /dev/ttyXX device. */
|
|
{
|
|
struct group *gp = getgrnam("tty");
|
|
fchown(slavefd, getuid(), gp ? gp->gr_gid : -1);
|
|
fchmod(slavefd, 0600);
|
|
}
|
|
#endif
|
|
|
|
close(pty_master_fd);
|
|
close(0);
|
|
close(1);
|
|
close(2);
|
|
fcntl(slavefd, F_SETFD, 0); /* don't close on exec */
|
|
dup2(slavefd, 0);
|
|
dup2(slavefd, 1);
|
|
dup2(slavefd, 2);
|
|
setsid();
|
|
ioctl(slavefd, TIOCSCTTY, 1);
|
|
pgrp = getpid();
|
|
tcsetpgrp(slavefd, pgrp);
|
|
setpgrp();
|
|
close(open(name, O_WRONLY, 0));
|
|
setpgrp();
|
|
/* In case we were setgid-utmp or setuid-root, drop privs. */
|
|
setgid(getgid());
|
|
setuid(getuid());
|
|
/* Close everything _else_, for tidiness. */
|
|
for (i = 3; i < 1024; i++)
|
|
close(i);
|
|
{
|
|
char term_env_var[10 + sizeof(cfg.termtype)];
|
|
sprintf(term_env_var, "TERM=%s", cfg.termtype);
|
|
putenv(term_env_var);
|
|
}
|
|
if (pty_argv)
|
|
execvp(pty_argv[0], pty_argv);
|
|
else {
|
|
char *shell = getenv("SHELL");
|
|
char *shellname;
|
|
if (cfg.login_shell) {
|
|
char *p = strrchr(shell, '/');
|
|
shellname = smalloc(2+strlen(shell));
|
|
p = p ? p+1 : shell;
|
|
sprintf(shellname, "-%s", p);
|
|
} else
|
|
shellname = shell;
|
|
execl(getenv("SHELL"), shellname, NULL);
|
|
}
|
|
|
|
/*
|
|
* If we're here, exec has gone badly foom.
|
|
*/
|
|
perror("exec");
|
|
exit(127);
|
|
} else {
|
|
close(slavefd);
|
|
pty_child_pid = pid;
|
|
pty_child_dead = FALSE;
|
|
signal(SIGCHLD, sigchld_handler);
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Called to send data down the pty.
|
|
*/
|
|
static int pty_send(char *buf, int len)
|
|
{
|
|
while (len > 0) {
|
|
int ret = write(pty_master_fd, buf, len);
|
|
if (ret < 0) {
|
|
perror("write pty master");
|
|
exit(1);
|
|
}
|
|
buf += ret;
|
|
len -= ret;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Called to query the current socket sendability status.
|
|
*/
|
|
static int pty_sendbuffer(void)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Called to set the size of the window
|
|
*/
|
|
static void pty_size(void)
|
|
{
|
|
struct winsize size;
|
|
|
|
size.ws_row = (unsigned short)rows;
|
|
size.ws_col = (unsigned short)cols;
|
|
size.ws_xpixel = (unsigned short) cols * font_dimension(0);
|
|
size.ws_ypixel = (unsigned short) rows * font_dimension(1);
|
|
ioctl(pty_master_fd, TIOCSWINSZ, (void *)&size);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Send special codes.
|
|
*/
|
|
static void pty_special(Telnet_Special code)
|
|
{
|
|
/* Do nothing! */
|
|
return;
|
|
}
|
|
|
|
static Socket pty_socket(void)
|
|
{
|
|
return NULL; /* shouldn't ever be needed */
|
|
}
|
|
|
|
static int pty_sendok(void)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
static void pty_unthrottle(int backlog)
|
|
{
|
|
/* do nothing */
|
|
}
|
|
|
|
static int pty_ldisc(int option)
|
|
{
|
|
return 0; /* neither editing nor echoing */
|
|
}
|
|
|
|
static int pty_exitcode(void)
|
|
{
|
|
/* Shouldn't ever be required */
|
|
return 0;
|
|
}
|
|
|
|
Backend pty_backend = {
|
|
pty_init,
|
|
pty_send,
|
|
pty_sendbuffer,
|
|
pty_size,
|
|
pty_special,
|
|
pty_socket,
|
|
pty_exitcode,
|
|
pty_sendok,
|
|
pty_ldisc,
|
|
pty_unthrottle,
|
|
1
|
|
};
|