2 #define _XOPEN_SOURCE_EXTENDED
16 #include <sys/types.h>
18 #include <sys/ioctl.h>
30 #define UTMP_FILE "/var/run/utmp"
33 #define WTMP_FILE "/var/log/wtmp"
37 #define LASTLOG_FILE _PATH_LASTLOG
39 #define LASTLOG_FILE "/var/log/lastlog"
44 * Set up a default for vaguely sane systems. The idea is that if
45 * OMIT_UTMP is not defined, then at least one of the symbols which
46 * enable particular forms of utmp processing should be, if only so
47 * that a link error can warn you that you should have defined
48 * OMIT_UTMP if you didn't want any. Currently HAVE_PUTUTLINE is
49 * the only such symbol.
52 #if !defined HAVE_PUTUTLINE
53 #define HAVE_PUTUTLINE
58 int pty_stamp_utmp = 1;
59 static int pty_stamped_utmp = 0;
60 static int pty_child_pid;
61 static sig_atomic_t pty_child_dead;
63 static struct utmp utmp_entry;
67 int pty_child_is_dead(void)
69 return pty_child_dead;
72 static void pty_size(void);
74 static void setup_utmp(char *ttyname)
78 struct lastlog lastlog_entry;
88 pw = getpwuid(getuid());
89 location = get_x_display();
90 memset(&utmp_entry, 0, sizeof(utmp_entry));
91 utmp_entry.ut_type = USER_PROCESS;
92 utmp_entry.ut_pid = getpid();
93 strncpy(utmp_entry.ut_line, ttyname+5, lenof(utmp_entry.ut_line));
94 strncpy(utmp_entry.ut_id, ttyname+8, lenof(utmp_entry.ut_id));
95 strncpy(utmp_entry.ut_user, pw->pw_name, lenof(utmp_entry.ut_user));
96 strncpy(utmp_entry.ut_host, location, lenof(utmp_entry.ut_host));
97 time(&utmp_entry.ut_time);
99 #if defined HAVE_PUTUTLINE
102 pututline(&utmp_entry);
106 if ((wtmp = fopen(WTMP_FILE, "a")) != NULL) {
107 fwrite(&utmp_entry, 1, sizeof(utmp_entry), wtmp);
112 memset(&lastlog_entry, 0, sizeof(lastlog_entry));
113 strncpy(lastlog_entry.ll_line, ttyname+5, lenof(lastlog_entry.ll_line));
114 strncpy(lastlog_entry.ll_host, location, lenof(lastlog_entry.ll_host));
115 time(&lastlog_entry.ll_time);
116 if ((lastlog = fopen(LASTLOG_FILE, "r+")) != NULL) {
117 fseek(lastlog, sizeof(lastlog_entry) * getuid(), SEEK_SET);
118 fwrite(&lastlog_entry, 1, sizeof(lastlog_entry), lastlog);
123 pty_stamped_utmp = 1;
128 static void cleanup_utmp(void)
133 if (!pty_stamp_utmp || !pty_stamped_utmp)
136 utmp_entry.ut_type = DEAD_PROCESS;
137 memset(utmp_entry.ut_user, 0, lenof(utmp_entry.ut_user));
138 time(&utmp_entry.ut_time);
140 if ((wtmp = fopen(WTMP_FILE, "a")) != NULL) {
141 fwrite(&utmp_entry, 1, sizeof(utmp_entry), wtmp);
145 memset(utmp_entry.ut_line, 0, lenof(utmp_entry.ut_line));
146 utmp_entry.ut_time = 0;
148 #if defined HAVE_PUTUTLINE
151 pututline(&utmp_entry);
155 pty_stamped_utmp = 0; /* ensure we never double-cleanup */
159 static void sigchld_handler(int signum)
163 pid = waitpid(-1, &status, WNOHANG);
164 if (pid == pty_child_pid && (WIFEXITED(status) || WIFSIGNALED(status)))
165 pty_child_dead = TRUE;
168 static void fatal_sig_handler(int signum)
170 signal(signum, SIG_DFL);
177 * Called to set up the pty.
179 * Returns an error message, or NULL on success.
181 * Also places the canonical host name into `realhost'. It must be
182 * freed by the caller.
184 static char *pty_init(char *host, int port, char **realhost, int nodelay)
187 char name[FILENAME_MAX];
192 const char chars1[] = "pqrstuvwxyz";
193 const char chars2[] = "0123456789abcdef";
195 char master_name[20];
197 for (p1 = chars1; *p1; p1++)
198 for (p2 = chars2; *p2; p2++) {
199 sprintf(master_name, "/dev/pty%c%c", *p1, *p2);
200 pty_master_fd = open(master_name, O_RDWR);
201 if (pty_master_fd >= 0) {
202 if (geteuid() == 0 ||
203 access(master_name, R_OK | W_OK) == 0)
205 close(pty_master_fd);
209 /* If we get here, we couldn't get a tty at all. */
210 fprintf(stderr, "pterm: unable to open a pseudo-terminal device\n");
214 strcpy(name, master_name);
215 name[5] = 't'; /* /dev/ptyXX -> /dev/ttyXX */
218 pty_master_fd = open("/dev/ptmx", O_RDWR);
220 if (pty_master_fd < 0) {
221 perror("/dev/ptmx: open");
225 if (grantpt(pty_master_fd) < 0) {
230 if (unlockpt(pty_master_fd) < 0) {
235 name[FILENAME_MAX-1] = '\0';
236 strncpy(name, ptsname(pty_master_fd), FILENAME_MAX-1);
240 * Trap as many fatal signals as we can in the hope of having
241 * the best chance to clean up utmp before termination.
243 signal(SIGHUP, fatal_sig_handler);
244 signal(SIGINT, fatal_sig_handler);
245 signal(SIGQUIT, fatal_sig_handler);
246 signal(SIGILL, fatal_sig_handler);
247 signal(SIGABRT, fatal_sig_handler);
248 signal(SIGFPE, fatal_sig_handler);
249 signal(SIGPIPE, fatal_sig_handler);
250 signal(SIGALRM, fatal_sig_handler);
251 signal(SIGTERM, fatal_sig_handler);
252 signal(SIGSEGV, fatal_sig_handler);
253 signal(SIGUSR1, fatal_sig_handler);
254 signal(SIGUSR2, fatal_sig_handler);
256 signal(SIGBUS, fatal_sig_handler);
259 signal(SIGPOLL, fatal_sig_handler);
262 signal(SIGPROF, fatal_sig_handler);
265 signal(SIGSYS, fatal_sig_handler);
268 signal(SIGTRAP, fatal_sig_handler);
271 signal(SIGVTALRM, fatal_sig_handler);
274 signal(SIGXCPU, fatal_sig_handler);
277 signal(SIGXFSZ, fatal_sig_handler);
280 signal(SIGIO, fatal_sig_handler);
282 /* Also clean up utmp on normal exit. */
283 atexit(cleanup_utmp);
287 * Fork and execute the command.
301 slavefd = open(name, O_RDWR);
303 perror("slave pty: open");
308 /* We need to chown/chmod the /dev/ttyXX device. */
310 struct group *gp = getgrnam("tty");
311 fchown(slavefd, getuid(), gp ? gp->gr_gid : -1);
312 fchmod(slavefd, 0600);
316 close(pty_master_fd);
320 fcntl(slavefd, F_SETFD, 0); /* don't close on exec */
325 ioctl(slavefd, TIOCSCTTY, 1);
327 tcsetpgrp(slavefd, pgrp);
329 close(open(name, O_WRONLY, 0));
331 /* In case we were setgid-utmp or setuid-root, drop privs. */
334 /* Close everything _else_, for tidiness. */
335 for (i = 3; i < 1024; i++)
338 char term_env_var[10 + sizeof(cfg.termtype)];
339 sprintf(term_env_var, "TERM=%s", cfg.termtype);
340 putenv(term_env_var);
343 execvp(pty_argv[0], pty_argv);
345 execl(getenv("SHELL"), getenv("SHELL"), NULL);
347 * If we're here, exec has gone badly foom.
354 pty_child_dead = FALSE;
355 signal(SIGCHLD, sigchld_handler);
362 * Called to send data down the pty.
364 static int pty_send(char *buf, int len)
367 int ret = write(pty_master_fd, buf, len);
369 perror("write pty master");
379 * Called to query the current socket sendability status.
381 static int pty_sendbuffer(void)
387 * Called to set the size of the window
389 static void pty_size(void)
393 size.ws_row = (unsigned short)rows;
394 size.ws_col = (unsigned short)cols;
395 ioctl(pty_master_fd, TIOCSWINSZ, (void *)&size);
400 * Send special codes.
402 static void pty_special(Telnet_Special code)
408 static Socket pty_socket(void)
410 return NULL; /* shouldn't ever be needed */
413 static int pty_sendok(void)
418 static void pty_unthrottle(int backlog)
423 static int pty_ldisc(int option)
425 return 0; /* neither editing nor echoing */
428 static int pty_exitcode(void)
430 /* Shouldn't ever be required */
434 Backend pty_backend = {