Adding upstream version 2.12.0.upstream/2.12.0

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 177 insertions, 0 deletions

diff --git a/lib/security.c b/lib/security.c
new file mode 100644
index 0000000..92cccc3
--- /dev/null
+++ b/lib/security.c
@@ -0,0 +1,177 @@
+/*
+ * security.c: Routines to aid secure uid operations
+ *
+ * Copyright (C) 1994, 1995 Graeme W. Wilford. (Wilf.)
+ * Copyright (C) 2001, 2003, 2004, 2007, 2010, 2011 Colin Watson.
+ *
+ * This file is part of man-db.
+ *
+ * man-db is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * man-db is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with man-db; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * Mon Aug  8 20:35:30 BST 1994  Wilf. (G.Wilford@ee.surrey.ac.uk)
+ */
+
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif /* HAVE_CONFIG_H */
+
+#include <stdbool.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <assert.h>
+#include <errno.h>
+#include <sys/types.h>
+
+#include "attribute.h"
+#include "error.h"
+#include "gettext.h"
+#define _(String) gettext (String)
+
+#include "manconfig.h"
+
+#include "cleanup.h"
+#include "debug.h"
+#include "fatal.h"
+#include "security.h"
+
+#ifdef MAN_OWNER
+
+   /*
+    * This is the name of the user that the preformatted man pages belong to.
+    * If you are running man as a setuid program, you should make sure
+    * that all of the cat pages and the directories that
+    * they live in are writeable by this user.
+    */
+
+#  include <pwd.h>
+#  include <unistd.h>
+
+#  include "idpriv.h"
+
+uid_t ruid;				/* initial real user id */
+uid_t euid;				/* initial effective user id */
+uid_t uid;				/* current euid */
+gid_t rgid;				/* initial real group id */
+gid_t egid;				/* initial effective group id */
+gid_t gid;				/* current egid */
+
+static struct passwd *man_owner;
+
+/* Keep a count of how many times we've dropped privileges, and only regain
+ * them if regain_effective_privs() is called an equal number of times.
+ */
+static int priv_drop_count = 0;
+
+static void gripe_set_euid (void)
+{
+	fatal (errno, _("can't set effective uid"));
+}
+
+#endif /* MAN_OWNER */
+
+void init_security (void)
+{
+#ifdef MAN_OWNER
+	ruid = getuid ();
+	uid = euid = geteuid ();
+	debug ("ruid=%d, euid=%d\n", (int) ruid, (int) euid);
+	rgid = getgid ();
+	gid = egid = getegid ();
+	debug ("rgid=%d, egid=%d\n", (int) rgid, (int) egid);
+	priv_drop_count = 0;
+	drop_effective_privs ();
+#endif /* MAN_OWNER */
+}
+
+bool ATTRIBUTE_PURE running_setuid (void)
+{
+#ifdef MAN_OWNER
+	return ruid != euid;
+#else /* !MAN_OWNER */
+	return false;
+#endif
+}
+
+#ifdef MAN_OWNER
+/* Return a pointer to the password entry structure for MAN_OWNER. This
+ * structure will be statically stored.
+ */
+struct passwd *get_man_owner (void)
+{
+	if (man_owner)
+		return man_owner;
+
+	man_owner = getpwnam (MAN_OWNER);
+	if (!man_owner)
+		error (FAIL, 0, _("the setuid man user \"%s\" does not exist"),
+		       MAN_OWNER);
+	assert (man_owner);
+	return man_owner;
+}
+#endif /* MAN_OWNER */
+
+/*
+ * function to gain user privs by either (a) dropping effective privs
+ * completely (saved ids) or (b) reversing euid w/ uid.
+ * Ignore if superuser.
+ */
+void drop_effective_privs (void)
+{
+#ifdef MAN_OWNER
+	if (uid != ruid) {
+		debug ("drop_effective_privs()\n");
+		if (idpriv_temp_drop ())
+			gripe_set_euid ();
+		uid = ruid;
+		gid = rgid;
+	}
+
+	priv_drop_count++;
+#endif /* MAN_OWNER */
+}
+
+/*
+ * function to (re)gain setuid privs by (a) setting euid from suid or (b)
+ * (re)reversing uid w/ euid. Ignore if superuser.
+ */
+void regain_effective_privs (void)
+{
+#ifdef MAN_OWNER
+	if (priv_drop_count) {
+		priv_drop_count--;
+		if (priv_drop_count)
+			return;
+	}
+
+	if (uid != euid) {
+		debug ("regain_effective_privs()\n");
+		if (idpriv_temp_restore ())
+			gripe_set_euid ();
+
+		uid = euid;
+		gid = egid;
+	}
+#endif /* MAN_OWNER */
+}
+
+/* Pipeline command pre-exec hook to permanently drop privileges. */
+void drop_privs (void *data MAYBE_UNUSED)
+{
+#ifdef MAN_OWNER
+	if (idpriv_drop ())
+		gripe_set_euid ();
+#endif /* MAN_OWNER */
+}