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--- shadow-4.0.3/src/su.c.orig 2002-10-20 16:43:21.000000000 +0200
+++ shadow-4.0.3/src/su.c 2002-10-20 16:50:57.000000000 +0200
@@ -134,6 +134,108 @@
exit (1);
}
+#ifdef USE_PAM
+static int caught=0;
+
+/* Signal handler for parent process later */
+static void su_catch_sig(int sig)
+{
+ ++caught;
+}
+
+/* This I ripped out of su.c from sh-utils after the Mandrake pam patch
+ * have been applied. Some work was needed to get it integrated into
+ * su.c from shadow.
+ */
+static void run_shell (const char *shellstr, char *args[], int doshell)
+{
+ int child;
+ sigset_t ourset;
+ int status;
+ int ret;
+
+ child = fork();
+ if (child == 0) { /* child shell */
+ pam_end (pamh, PAM_SUCCESS);
+
+ if (doshell)
+ shell (shellstr, (char *) args[0]);
+ else
+ (void) execv (shellstr, (char **) args);
+ {
+ int exit_status = (errno == ENOENT ? 127 : 126);
+ exit (exit_status);
+ }
+ } else if (child == -1) {
+ (void) fprintf(stderr, "%s: Cannot fork user shell\n", Prog);
+ SYSLOG ((LOG_WARN, "Cannot execute %s", pwent.pw_shell));
+ closelog ();
+ exit(1);
+ }
+ /* parent only */
+ sigfillset(&ourset);
+ if (sigprocmask(SIG_BLOCK, &ourset, NULL)) {
+ (void) fprintf(stderr, "%s: signal malfunction\n", Prog);
+ caught = 1;
+ }
+ if (!caught) {
+ struct sigaction action;
+ action.sa_handler = su_catch_sig;
+ sigemptyset(&action.sa_mask);
+ action.sa_flags = 0;
+ sigemptyset(&ourset);
+
+ if (sigaddset(&ourset, SIGTERM)
+ || sigaddset(&ourset, SIGALRM)
+ || sigaction(SIGTERM, &action, NULL)
+ || sigprocmask(SIG_UNBLOCK, &ourset, NULL)
+ ) {
+ fprintf(stderr, "%s: signal masking malfunction\n", Prog);
+ caught = 1;
+ }
+ }
+
+ if (!caught) {
+ do {
+ int pid;
+
+ pid = waitpid(-1, &status, WUNTRACED);
+
+ if (WIFSTOPPED(status)) {
+ kill(getpid(), SIGSTOP);
+ /* once we get here, we must have resumed */
+ kill(pid, SIGCONT);
+ }
+ } while (WIFSTOPPED(status));
+ }
+
+ if (caught) {
+ fprintf(stderr, "\nSession terminated, killing shell...");
+ kill (child, SIGTERM);
+ }
+
+ ret = pam_close_session(pamh, 0);
+ if (ret != PAM_SUCCESS) {
+ SYSLOG ((LOG_ERR, "pam_close_session: %s",
+ pam_strerror (pamh, ret)));
+ fprintf (stderr, "%s: %s\n", Prog,
+ pam_strerror (pamh, ret));
+ pam_end (pamh, ret);
+ exit (1);
+ }
+
+ ret = pam_end(pamh, PAM_SUCCESS);
+
+ if (caught) {
+ sleep(2);
+ kill(child, SIGKILL);
+ fprintf(stderr, " ...killed.\n");
+ exit(-1);
+ }
+
+ exit (WEXITSTATUS(status));
+}
+#endif
/*
* su - switch user id
@@ -152,6 +254,7 @@
int main (int argc, char **argv)
{
char *cp;
+ char **envcp;
const char *tty = 0; /* Name of tty SU is run from */
int doshell = 0;
int fakelogin = 0;
@@ -252,6 +355,14 @@
*/
if ((cp = getenv ("TERM")))
addenv ("TERM", cp);
+ /*
+ * Also leave DISPLAY and XAUTHORITY if present, else
+ * pam_xauth will not work.
+ */
+ if ((cp = getenv ("DISPLAY")))
+ addenv ("DISPLAY", cp);
+ if ((cp = getenv ("XAUTHORITY")))
+ addenv ("XAUTHORITY", cp);
} else {
while (*envp)
addenv (*envp++, NULL);
@@ -507,7 +618,10 @@
}
#endif
+/* setup the environment for pam later on, else we run into auth problems */
+#ifndef USE_PAM
environ = newenvp; /* make new environment active */
+#endif
if (getenv ("IFS")) /* don't export user IFS ... */
addenv ("IFS= \t\n", NULL); /* ... instead, set a safe IFS */
@@ -555,6 +669,31 @@
exit (1);
}
+ ret = pam_open_session (pamh, 0);
+ if (ret != PAM_SUCCESS) {
+ SYSLOG ((LOG_ERR, "pam_open_session: %s",
+ pam_strerror (pamh, ret)));
+ fprintf (stderr, "%s: %s\n", Prog,
+ pam_strerror (pamh, ret));
+ pam_end (pamh, ret);
+ exit (1);
+ }
+
+ /* we need to setup the environment *after* pam_open_session(),
+ * else the UID is changed before stuff like pam_xauth could
+ * run, and we cannot access /etc/shadow and co
+ */
+ environ = newenvp; /* make new environment active */
+
+ /* update environment with all pam set variables */
+ envcp = pam_getenvlist(pamh);
+ if(envcp) {
+ while(*envcp) {
+ putenv(*envcp);
+ envcp++;
+ }
+ }
+
/* become the new user */
if (change_uid (&pwent)) {
pam_setcred (pamh, PAM_DELETE_CRED);
@@ -562,9 +701,6 @@
exit (1);
}
- /* now we are done using PAM */
- pam_end (pamh, PAM_SUCCESS);
-
#else /* !USE_PAM */
if (!amroot) /* no limits if su from root */
setup_limits (&pwent);
@@ -622,13 +758,21 @@
*/
argv[-1] = pwent.pw_shell;
+#ifndef USE_PAM
(void) execv (pwent.pw_shell, &argv[-1]);
+#else
+ run_shell (pwent.pw_shell, &argv[-1], 0);
+#endif
(void) fprintf (stderr, _("No shell\n"));
SYSLOG ((LOG_WARN, "Cannot execute %s", pwent.pw_shell));
closelog ();
exit (1);
}
+#ifndef USE_PAM
shell (pwent.pw_shell, cp);
+#else
+ run_shell (pwent.pw_shell, &cp, 1);
+#endif
/* NOT REACHED */
exit (1);
}
|
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