X-Git-Url: https://diplodocus.org/git/nmh/blobdiff_plain/05dba91fcb152e1941e7f7f145b1d830c5e8f6d0..2a795362ca3ea8da3879ea14d81ee2238e40ad91:/uip/slocal.c

diff --git a/uip/slocal.c b/uip/slocal.c
index a807d816..6bbcde6a 100644
--- a/uip/slocal.c
+++ b/uip/slocal.c
@@ -34,6 +34,10 @@
 #include <sys/ioctl.h>
 #include <fcntl.h>
 
+/* Hopefully, grp.h declares initgroups().  If we run into a platform
+   where it doesn't, we could consider declaring it here as well. */
+#include <grp.h>
+
 /* This define is needed for Berkeley db v2 and above to
  * make the header file expose the 'historical' ndbm APIs.
  * We define it unconditionally because this is simple and
@@ -179,14 +183,14 @@ int
 main (int argc, char **argv)
 {
     int fd, status;
-    FILE *fp = stdin;
+    FILE *fp;
     char *cp, *mdlvr = NULL, buf[BUFSIZ];
     char mailbox[BUFSIZ], tmpfil[BUFSIZ];
     char **argp, **arguments;
 
     if (nmh_init(argv[0], 0 /* use context_foil() */)) { return 1; }
 
-    mts_init (invo_name);
+    mts_init ();
     arguments = getarguments (invo_name, argc, argv, 0);
     argp = arguments;
 
@@ -269,15 +273,28 @@ main (int argc, char **argv)
 
     if (addr == NULL)
 	addr = getusername ();
-    if (user == NULL)
-	user = (cp = strchr(addr, '.')) ? ++cp : addr;
+    if (user == NULL) {
+	user = getusername ();
+    }
     if ((pw = getpwnam (user)) == NULL)
 	adios (NULL, "no such local user as %s", user);
 
     if (chdir (pw->pw_dir) == -1)
-	chdir ("/");
+	if (chdir ("/") < 0) {
+	    advise ("/", "chdir");
+	}
     umask (0077);
 
+    if (geteuid() == 0) {
+	if (setgid (pw->pw_gid) != 0) {
+	    adios ("setgid", "unable to set group to %ld", (long) pw->pw_gid);
+	}
+	initgroups (pw->pw_name, pw->pw_gid);
+	if (setuid (pw->pw_uid) != 0) {
+	    adios ("setuid", "unable to set user to %ld", (long) pw->pw_uid);
+	}
+    }
+
     if (info == NULL)
 	info = "";
 
@@ -1053,8 +1070,12 @@ usr_pipe (int fd_arg, char *cmd, char *pgm, char **vec, int suppress)
 	    /* child process */
 	    if (fd != 0)
 		dup2 (fd, 0);
-	    freopen ("/dev/null", "w", stdout);
-	    freopen ("/dev/null", "w", stderr);
+	    if (freopen ("/dev/null", "w", stdout) == NULL) {
+		advise ("stdout", "freopen");
+	    }
+	    if (freopen ("/dev/null", "w", stderr) == NULL) {
+		advise ("stderr", "freopen");
+	    }
 	    if (fd != 3)
 		dup2 (fd, 3);
 	    closefds (4);
@@ -1400,6 +1421,7 @@ suppress_duplicates (int fd, char *file)
     rewind (in);
 
     for (;;) {
+        int failed_to_lock = 0;
 	int bufsz = sizeof buf;
 	state = m_getfld (&gstate, name, buf, &bufsz, in);
 	switch (state) {
@@ -1437,7 +1459,8 @@ suppress_duplicates (int fd, char *file)
 		 * This will fail if your Maildelivery file doesn't
 		 * exist.
 		 */
-		if ((lockfd = lkopendata(file, O_RDWR, 0)) == -1) {
+		if ((lockfd = lkopendata(file, O_RDWR, 0, &failed_to_lock))
+		    == -1) {
 		    advise (file, "unable to perform file locking on");
 		    free (cp);
 		    fclose (in);