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-rw-r--r--libbb/utmp.c123
1 files changed, 86 insertions, 37 deletions
diff --git a/libbb/utmp.c b/libbb/utmp.c
index 06b939b9d..d6ba336e3 100644
--- a/libbb/utmp.c
+++ b/libbb/utmp.c
@@ -15,37 +15,87 @@ static void touch(const char *filename)
close(open(filename, O_WRONLY | O_CREAT, 0664));
}
+// TODO: move to libbb
+static const char* skip_dev_pfx(const char *tty_name)
+{
+ if (strncmp(tty_name, "/dev/", 5) == 0)
+ tty_name += 5;
+ return tty_name;
+}
+
+void FAST_FUNC write_new_utmp(pid_t pid, int new_type, const char *tty_name, const char *username, const char *hostname)
+{
+ struct utmp utent;
+ char *id;
+ unsigned width;
+
+ memset(&utent, 0, sizeof(utent));
+ utent.ut_pid = pid;
+ utent.ut_type = new_type;
+ tty_name = skip_dev_pfx(tty_name);
+ safe_strncpy(utent.ut_line, tty_name, sizeof(utent.ut_line));
+ if (username)
+ safe_strncpy(utent.ut_user, username, sizeof(utent.ut_user));
+ if (hostname)
+ safe_strncpy(utent.ut_host, hostname, sizeof(utent.ut_host));
+ utent.ut_tv.tv_sec = time(NULL);
+
+ /* Invent our own ut_id. ut_id is only 4 chars wide.
+ * Try to fit something remotely meaningful... */
+ id = utent.ut_id;
+ width = sizeof(utent.ut_id);
+ if (tty_name[0] == 'p') {
+ /* if "ptyXXX", map to "pXXX" */
+ /* if "pts/XX", map to "p/XX" */
+ *id++ = 'p';
+ width--;
+ } /* else: usually it's "ttyXXXX", map to "XXXX" */
+ if (strlen(tty_name) > 3)
+ tty_name += 3;
+ strncpy(id, tty_name, width);
+
+ touch(_PATH_UTMP);
+ //utmpname(_PATH_UTMP);
+ setutent();
+ /* Append new one (hopefully, unless we collide on ut_id) */
+ pututline(&utent);
+ endutent();
+
+#if ENABLE_FEATURE_WTMP
+ /* "man utmp" says wtmp file should *not* be created automagically */
+ /*touch(bb_path_wtmp_file);*/
+ updwtmp(bb_path_wtmp_file, &utent);
+#endif
+}
+
/*
* Read "man utmp" to make sense out of it.
*/
-void FAST_FUNC update_utmp(int new_type, const char *short_tty, const char *username, const char *opt_host)
+void FAST_FUNC update_utmp(pid_t pid, int new_type, const char *tty_name, const char *username, const char *hostname)
{
struct utmp utent;
- struct utmp *ut;
- pid_t pid;
+ struct utmp *utp;
touch(_PATH_UTMP);
- utmpname(_PATH_UTMP);
+ //utmpname(_PATH_UTMP);
setutent();
- pid = getpid();
/* Did init/getty/telnetd/sshd/... create an entry for us?
* It should be (new_type-1), but we'd also reuse
* any other potentially stale xxx_PROCESS entry */
- while ((ut = getutent()) != NULL) {
- if (ut->ut_pid == pid
+ while ((utp = getutent()) != NULL) {
+ if (utp->ut_pid == pid
// && ut->ut_line[0]
- && ut->ut_id[0] /* must have nonzero id */
- && ( ut->ut_type == INIT_PROCESS
- || ut->ut_type == LOGIN_PROCESS
- || ut->ut_type == USER_PROCESS
- || ut->ut_type == DEAD_PROCESS
+ && utp->ut_id[0] /* must have nonzero id */
+ && ( utp->ut_type == INIT_PROCESS
+ || utp->ut_type == LOGIN_PROCESS
+ || utp->ut_type == USER_PROCESS
+ || utp->ut_type == DEAD_PROCESS
)
) {
- utent = *ut; /* struct copy */
- if (ut->ut_type >= new_type) {
+ if (utp->ut_type >= new_type) {
/* Stale record. Nuke hostname */
- memset(utent.ut_host, 0, sizeof(utent.ut_host));
+ memset(utp->ut_host, 0, sizeof(utp->ut_host));
}
/* NB: pututline (see later) searches for matching utent
* using getutid(utent) - we must not change ut_id
@@ -54,39 +104,38 @@ void FAST_FUNC update_utmp(int new_type, const char *short_tty, const char *user
break;
}
}
- endutent();
+ //endutent(); - no need, pututline can deal with (and actually likes)
+ //the situation when utmp file is positioned on found record
- if (!ut) {
- /* Didn't find anything, create new one */
- memset(&utent, 0, sizeof(utent));
- utent.ut_pid = pid;
- /* Invent our own ut_id. ut_id is only 4 chars wide.
- * Try to fit something remotely meaningful... */
- if (short_tty[0] == 'p') {
- /* if "ptyXXX", map to "pXXX" */
- /* if "pts/XX", map to "p/XX" */
- utent.ut_id[0] = 'p';
- strncpy(utent.ut_id + 1, short_tty + 3, sizeof(utent.ut_id)-1);
- } else {
- /* assuming it's "ttyXXXX", map to "XXXX" */
- strncpy(utent.ut_id, short_tty + 3, sizeof(utent.ut_id));
- }
+ if (!utp) {
+ if (new_type != DEAD_PROCESS)
+ write_new_utmp(pid, new_type, tty_name, username, hostname);
+ else
+ endutent();
+ return;
}
+ /* Make a copy. We can't use *utp, pututline's internal getutid
+ * will overwrite it before it is used! */
+ utent = *utp;
+
utent.ut_type = new_type;
- safe_strncpy(utent.ut_line, short_tty, sizeof(utent.ut_line));
- safe_strncpy(utent.ut_user, username, sizeof(utent.ut_user));
- if (opt_host)
- safe_strncpy(utent.ut_host, opt_host, sizeof(utent.ut_host));
+ if (tty_name)
+ safe_strncpy(utent.ut_line, skip_dev_pfx(tty_name), sizeof(utent.ut_line));
+ if (username)
+ safe_strncpy(utent.ut_user, username, sizeof(utent.ut_user));
+ if (hostname)
+ safe_strncpy(utent.ut_host, hostname, sizeof(utent.ut_host));
utent.ut_tv.tv_sec = time(NULL);
/* Update, or append new one */
- setutent();
+ //setutent();
pututline(&utent);
endutent();
#if ENABLE_FEATURE_WTMP
- touch(bb_path_wtmp_file);
+ /* "man utmp" says wtmp file should *not* be created automagically */
+ /*touch(bb_path_wtmp_file);*/
updwtmp(bb_path_wtmp_file, &utent);
#endif
}