1 files changed, 99 insertions, 0 deletions

diff --git a/other/openssh-2.1.1p4/uidswap.c b/other/openssh-2.1.1p4/uidswap.c
new file mode 100644
index 0000000..3fd0eef
--- /dev/null
+++ b/other/openssh-2.1.1p4/uidswap.c
@@ -0,0 +1,99 @@
+/*
+ * Author: Tatu Ylonen <ylo@cs.hut.fi>
+ * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
+ *                    All rights reserved
+ * Created: Sat Sep  9 01:56:14 1995 ylo
+ * Code for uid-swapping.
+ */
+
+#include "includes.h"
+RCSID("$OpenBSD: uidswap.c,v 1.7 2000/06/20 01:39:45 markus Exp $");
+
+#include "ssh.h"
+#include "uidswap.h"
+#ifdef WITH_IRIX_AUDIT
+#include <sat.h>
+#endif /* WITH_IRIX_AUDIT */
+
+/*
+ * Note: all these functions must work in all of the following cases:
+ *    1. euid=0, ruid=0
+ *    2. euid=0, ruid!=0
+ *    3. euid!=0, ruid!=0
+ * Additionally, they must work regardless of whether the system has
+ * POSIX saved uids or not.
+ */
+
+#ifdef _POSIX_SAVED_IDS
+/* Lets assume that posix saved ids also work with seteuid, even though that
+   is not part of the posix specification. */
+#define SAVED_IDS_WORK_WITH_SETEUID
+
+/* Saved effective uid. */
+static uid_t saved_euid = 0;
+
+#endif /* _POSIX_SAVED_IDS */
+
+/*
+ * Temporarily changes to the given uid.  If the effective user
+ * id is not root, this does nothing.  This call cannot be nested.
+ */
+void
+temporarily_use_uid(uid_t uid)
+{
+#ifdef SAVED_IDS_WORK_WITH_SETEUID
+        /* Save the current euid. */
+        saved_euid = geteuid();
+
+        /* Set the effective uid to the given (unprivileged) uid. */
+        if (seteuid(uid) == -1)
+                debug("seteuid %d: %.100s", (int) uid, strerror(errno));
+#else /* SAVED_IDS_WORK_WITH_SETUID */
+        /* Propagate the privileged uid to all of our uids. */
+        if (setuid(geteuid()) < 0)
+                debug("setuid %d: %.100s", (int) geteuid(), strerror(errno));
+
+        /* Set the effective uid to the given (unprivileged) uid. */
+        if (seteuid(uid) == -1)
+                debug("seteuid %d: %.100s", (int) uid, strerror(errno));
+#endif /* SAVED_IDS_WORK_WITH_SETEUID */
+}
+
+/*
+ * Restores to the original uid.
+ */
+void
+restore_uid()
+{
+#ifdef SAVED_IDS_WORK_WITH_SETEUID
+        /* Set the effective uid back to the saved uid. */
+        if (seteuid(saved_euid) < 0)
+                debug("seteuid %d: %.100s", (int) saved_euid, strerror(errno));
+#else /* SAVED_IDS_WORK_WITH_SETEUID */
+        /*
+         * We are unable to restore the real uid to its unprivileged value.
+         * Propagate the real uid (usually more privileged) to effective uid
+         * as well.
+         */
+        setuid(getuid());
+#endif /* SAVED_IDS_WORK_WITH_SETEUID */
+}
+
+/*
+ * Permanently sets all uids to the given uid.  This cannot be
+ * called while temporarily_use_uid is effective.
+ */
+void
+permanently_set_uid(uid_t uid)
+{
+#ifdef WITH_IRIX_AUDIT
+        if (sysconf(_SC_AUDIT)) {
+                debug("Setting sat id to %d", (int) uid);
+                if (satsetid(uid))
+                        fatal("error setting satid: %.100s", strerror(errno));
+        }
+#endif /* WITH_IRIX_AUDIT */
+
+        if (setuid(uid) < 0)
+                debug("setuid %d: %.100s", (int) uid, strerror(errno));
+}