[src/netbsd-1-5]: src/crypto/dist/ssh Pull up revisions 1.1.1.2-1.1.1.3 (requ...

[he <he%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/6a910c95dcda
branches:  netbsd-1-5
changeset: 490716:6a910c95dcda
user:      he <he%NetBSD.org@localhost>
date:      Mon Feb 26 20:33:51 2001 +0000

description:
Pull up revisions 1.1.1.2-1.1.1.3 (requested by itojun):
  Update SSH to version found on trunk as of 26 Feb 2001.

diffstat:

 crypto/dist/ssh/uidswap.c |  91 +++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 91 insertions(+), 0 deletions(-)

diffs (95 lines):

diff -r 6d1a748fe2ab -r 6a910c95dcda crypto/dist/ssh/uidswap.c
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/crypto/dist/ssh/uidswap.c Mon Feb 26 20:33:51 2001 +0000
@@ -0,0 +1,91 @@
+/*
+ * Author: Tatu Ylonen <ylo%cs.hut.fi@localhost>
+ * Copyright (c) 1995 Tatu Ylonen <ylo%cs.hut.fi@localhost>, Espoo, Finland
+ *                    All rights reserved
+ * Code for uid-swapping.
+ *
+ * As far as I am concerned, the code I have written for this software
+ * can be used freely for any purpose.  Any derived versions of this
+ * software must be clearly marked as such, and if the derived work is
+ * incompatible with the protocol description in the RFC file, it must be
+ * called by a name other than "ssh" or "Secure Shell".
+ */
+
+#include "includes.h"
+RCSID("$OpenBSD: uidswap.c,v 1.13 2001/01/21 19:06:01 markus Exp $");
+
+#include "log.h"
+#include "uidswap.h"
+
+/*
+ * 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 %u: %.100s", (u_int) uid, strerror(errno));
+#else /* SAVED_IDS_WORK_WITH_SETEUID */
+       /* Propagate the privileged uid to all of our uids. */
+       if (setuid(geteuid()) < 0)
+               debug("setuid %u: %.100s", (u_int) geteuid(), strerror(errno));
+
+       /* Set the effective uid to the given (unprivileged) uid. */
+       if (seteuid(uid) == -1)
+               debug("seteuid %u: %.100s", (u_int) uid, strerror(errno));
+#endif /* SAVED_IDS_WORK_WITH_SETEUID */
+}
+
+/*
+ * Restores to the original uid.
+ */
+void
+restore_uid(void)
+{
+#ifdef SAVED_IDS_WORK_WITH_SETEUID
+       /* Set the effective uid back to the saved uid. */
+       if (seteuid(saved_euid) < 0)
+               debug("seteuid %u: %.100s", (u_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)
+{
+       if (setuid(uid) < 0)
+               debug("setuid %u: %.100s", (u_int) uid, strerror(errno));
+}