Adding upstream version 9.1.upstream/9.1

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

1 files changed, 762 insertions, 0 deletions

diff --git a/lib/privs.c b/lib/privs.c
new file mode 100644
index 0000000..accd989
--- /dev/null
+++ b/lib/privs.c
@@ -0,0 +1,762 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Zebra privileges.
+ *
+ * Copyright (C) 2003 Paul Jakma.
+ * Copyright (c) 2005, 2011, Oracle and/or its affiliates. All rights reserved.
+ */
+#include <zebra.h>
+#include "log.h"
+#include "privs.h"
+#include "memory.h"
+#include "frr_pthread.h"
+#include "lib_errors.h"
+#include "lib/queue.h"
+
+DEFINE_MTYPE_STATIC(LIB, PRIVS, "Privilege information");
+
+/*
+ * Different capabilities/privileges apis have different characteristics: some
+ * are process-wide, and some are per-thread.
+ */
+#ifdef HAVE_CAPABILITIES
+#ifdef HAVE_LCAPS
+static const bool privs_per_process;  /* = false */
+#else
+static const bool privs_per_process = true;
+#endif /* HAVE_LCAPS */
+#else /* HAVE_CAPABILITIES */
+static const bool privs_per_process = true;
+#endif
+
+#ifdef HAVE_CAPABILITIES
+
+/* sort out some generic internal types for:
+ *
+ * privilege values (cap_value_t, priv_t) 	-> pvalue_t
+ * privilege set (..., priv_set_t) 		-> pset_t
+ * privilege working storage (cap_t, ...) 	-> pstorage_t
+ *
+ * values we think of as numeric (they're ints really, but we dont know)
+ * sets are mostly opaque, to hold a set of privileges, related in some way.
+ * storage binds together a set of sets we're interested in.
+ * (in reality: cap_value_t and priv_t are ints)
+ */
+#ifdef HAVE_LCAPS
+/* Linux doesn't have a 'set' type: a set of related privileges */
+struct _pset {
+	int num;
+	cap_value_t *caps;
+};
+typedef cap_value_t pvalue_t;
+typedef struct _pset pset_t;
+typedef cap_t pstorage_t;
+
+#else /* no LCAPS */
+#error "HAVE_CAPABILITIES defined, but neither LCAPS nor Solaris Capabilties!"
+#endif /* HAVE_LCAPS */
+#endif /* HAVE_CAPABILITIES */
+
+/* the default NULL state we report is RAISED, but could be LOWERED if
+ * zprivs_terminate is called and the NULL handler is installed.
+ */
+static zebra_privs_current_t zprivs_null_state = ZPRIVS_RAISED;
+
+/* internal privileges state */
+static struct _zprivs_t {
+#ifdef HAVE_CAPABILITIES
+	pstorage_t caps;   /* working storage        */
+	pset_t *syscaps_p; /* system-type requested permitted caps    */
+	pset_t *syscaps_i; /* system-type requested inheritable caps  */
+#endif			   /* HAVE_CAPABILITIES */
+	uid_t zuid,	/* uid to run as            */
+		zsuid;     /* saved uid                */
+	gid_t zgid;	/* gid to run as            */
+	gid_t vtygrp;      /* gid for vty sockets      */
+} zprivs_state;
+
+/* externally exported but not directly accessed functions */
+#ifdef HAVE_CAPABILITIES
+int zprivs_change_caps(zebra_privs_ops_t);
+zebra_privs_current_t zprivs_state_caps(void);
+#endif /* HAVE_CAPABILITIES */
+int zprivs_change_uid(zebra_privs_ops_t);
+zebra_privs_current_t zprivs_state_uid(void);
+int zprivs_change_null(zebra_privs_ops_t);
+zebra_privs_current_t zprivs_state_null(void);
+
+#ifdef HAVE_CAPABILITIES
+/* internal capability API */
+static pset_t *zcaps2sys(zebra_capabilities_t *, int);
+static void zprivs_caps_init(struct zebra_privs_t *);
+static void zprivs_caps_terminate(void);
+
+/* Map of Quagga abstract capabilities to system capabilities */
+static struct {
+	int num;
+	pvalue_t *system_caps;
+} cap_map[ZCAP_MAX] = {
+#ifdef HAVE_LCAPS /* Quagga -> Linux capabilities mappings */
+		[ZCAP_SETID] =
+			{
+				2, (pvalue_t[]){CAP_SETGID, CAP_SETUID},
+			},
+		[ZCAP_BIND] =
+			{
+				1, (pvalue_t[]){CAP_NET_BIND_SERVICE},
+			},
+		[ZCAP_NET_ADMIN] =
+			{
+				1, (pvalue_t[]){CAP_NET_ADMIN},
+			},
+		[ZCAP_NET_RAW] =
+			{
+				1, (pvalue_t[]){CAP_NET_RAW},
+			},
+		[ZCAP_CHROOT] =
+			{
+				1,
+				(pvalue_t[]){
+					CAP_SYS_CHROOT,
+				},
+			},
+		[ZCAP_NICE] =
+			{
+				1, (pvalue_t[]){CAP_SYS_NICE},
+			},
+		[ZCAP_PTRACE] =
+			{
+				1, (pvalue_t[]){CAP_SYS_PTRACE},
+			},
+		[ZCAP_DAC_OVERRIDE] =
+			{
+				1, (pvalue_t[]){CAP_DAC_OVERRIDE},
+			},
+		[ZCAP_READ_SEARCH] =
+			{
+				1, (pvalue_t[]){CAP_DAC_READ_SEARCH},
+			},
+		[ZCAP_SYS_ADMIN] =
+			{
+				1, (pvalue_t[]){CAP_SYS_ADMIN},
+			},
+		[ZCAP_FOWNER] =
+			{
+				1, (pvalue_t[]){CAP_FOWNER},
+			},
+		[ZCAP_IPC_LOCK] =
+			{
+				1, (pvalue_t[]){CAP_IPC_LOCK},
+			},
+		[ZCAP_SYS_RAWIO] =
+			{
+				1, (pvalue_t[]){CAP_SYS_RAWIO},
+			},
+#endif /* HAVE_LCAPS */
+};
+
+#ifdef HAVE_LCAPS
+/* Linux forms of capabilities methods */
+/* convert zebras privileges to system capabilities */
+static pset_t *zcaps2sys(zebra_capabilities_t *zcaps, int num)
+{
+	pset_t *syscaps;
+	int i, j = 0, count = 0;
+
+	if (!num)
+		return NULL;
+
+	/* first count up how many system caps we have */
+	for (i = 0; i < num; i++)
+		count += cap_map[zcaps[i]].num;
+
+	if ((syscaps = XCALLOC(MTYPE_PRIVS, (sizeof(pset_t) * num))) == NULL) {
+		fprintf(stderr, "%s: could not allocate syscaps!", __func__);
+		return NULL;
+	}
+
+	syscaps->caps = XCALLOC(MTYPE_PRIVS, (sizeof(pvalue_t) * count));
+
+	if (!syscaps->caps) {
+		fprintf(stderr, "%s: could not XCALLOC caps!", __func__);
+		return NULL;
+	}
+
+	/* copy the capabilities over */
+	count = 0;
+	for (i = 0; i < num; i++)
+		for (j = 0; j < cap_map[zcaps[i]].num; j++)
+			syscaps->caps[count++] =
+				cap_map[zcaps[i]].system_caps[j];
+
+	/* iterations above should be exact same as previous count, obviously..
+	 */
+	syscaps->num = count;
+
+	return syscaps;
+}
+
+/* set or clear the effective capabilities to/from permitted */
+int zprivs_change_caps(zebra_privs_ops_t op)
+{
+	cap_flag_value_t cflag;
+
+	/* should be no possibility of being called without valid caps */
+	assert(zprivs_state.syscaps_p && zprivs_state.caps);
+	if (!(zprivs_state.syscaps_p && zprivs_state.caps))
+		exit(1);
+
+	if (op == ZPRIVS_RAISE)
+		cflag = CAP_SET;
+	else if (op == ZPRIVS_LOWER)
+		cflag = CAP_CLEAR;
+	else
+		return -1;
+
+	if (!cap_set_flag(zprivs_state.caps, CAP_EFFECTIVE,
+			  zprivs_state.syscaps_p->num,
+			  zprivs_state.syscaps_p->caps, cflag))
+		return cap_set_proc(zprivs_state.caps);
+	return -1;
+}
+
+zebra_privs_current_t zprivs_state_caps(void)
+{
+	int i;
+	cap_flag_value_t val;
+
+	/* should be no possibility of being called without valid caps */
+	assert(zprivs_state.syscaps_p && zprivs_state.caps);
+	if (!(zprivs_state.syscaps_p && zprivs_state.caps))
+		exit(1);
+
+	for (i = 0; i < zprivs_state.syscaps_p->num; i++) {
+		if (cap_get_flag(zprivs_state.caps,
+				 zprivs_state.syscaps_p->caps[i], CAP_EFFECTIVE,
+				 &val)) {
+			flog_err(
+				EC_LIB_SYSTEM_CALL,
+				"zprivs_state_caps: could not cap_get_flag, %s",
+				safe_strerror(errno));
+			return ZPRIVS_UNKNOWN;
+		}
+		if (val == CAP_SET)
+			return ZPRIVS_RAISED;
+	}
+	return ZPRIVS_LOWERED;
+}
+
+/** Release private cap state if allocated. */
+static void zprivs_state_free_caps(void)
+{
+	if (zprivs_state.syscaps_p) {
+		if (zprivs_state.syscaps_p->num)
+			XFREE(MTYPE_PRIVS, zprivs_state.syscaps_p->caps);
+
+		XFREE(MTYPE_PRIVS, zprivs_state.syscaps_p);
+	}
+
+	if (zprivs_state.syscaps_i) {
+		if (zprivs_state.syscaps_i->num)
+			XFREE(MTYPE_PRIVS, zprivs_state.syscaps_i->caps);
+
+		XFREE(MTYPE_PRIVS, zprivs_state.syscaps_i);
+	}
+
+	if (zprivs_state.caps) {
+		cap_free(zprivs_state.caps);
+		zprivs_state.caps = NULL;
+	}
+}
+
+static void zprivs_caps_init(struct zebra_privs_t *zprivs)
+{
+	/* Release allocated zcaps if this function was called before. */
+	zprivs_state_free_caps();
+
+	zprivs_state.syscaps_p = zcaps2sys(zprivs->caps_p, zprivs->cap_num_p);
+	zprivs_state.syscaps_i = zcaps2sys(zprivs->caps_i, zprivs->cap_num_i);
+
+	/* Tell kernel we want caps maintained across uid changes */
+	if (prctl(PR_SET_KEEPCAPS, 1, 0, 0, 0) == -1) {
+		fprintf(stderr,
+			"privs_init: could not set PR_SET_KEEPCAPS, %s\n",
+			safe_strerror(errno));
+		exit(1);
+	}
+
+	/* we have caps, we have no need to ever change back the original user
+	 */
+	/* only change uid if we don't have the correct one */
+	if ((zprivs_state.zuid) && (zprivs_state.zsuid != zprivs_state.zuid)) {
+		if (setreuid(zprivs_state.zuid, zprivs_state.zuid)) {
+			fprintf(stderr,
+				"zprivs_init (cap): could not setreuid, %s\n",
+				safe_strerror(errno));
+			exit(1);
+		}
+	}
+
+	if (!(zprivs_state.caps = cap_init())) {
+		fprintf(stderr, "privs_init: failed to cap_init, %s\n",
+			safe_strerror(errno));
+		exit(1);
+	}
+
+	if (cap_clear(zprivs_state.caps)) {
+		fprintf(stderr, "privs_init: failed to cap_clear, %s\n",
+			safe_strerror(errno));
+		exit(1);
+	}
+
+	/* set permitted caps, if any */
+	if (zprivs_state.syscaps_p && zprivs_state.syscaps_p->num) {
+		cap_set_flag(zprivs_state.caps, CAP_PERMITTED,
+			     zprivs_state.syscaps_p->num,
+			     zprivs_state.syscaps_p->caps, CAP_SET);
+	}
+
+	/* set inheritable caps, if any */
+	if (zprivs_state.syscaps_i && zprivs_state.syscaps_i->num) {
+		cap_set_flag(zprivs_state.caps, CAP_INHERITABLE,
+			     zprivs_state.syscaps_i->num,
+			     zprivs_state.syscaps_i->caps, CAP_SET);
+	}
+
+	/* apply caps. CAP_EFFECTIVE is cleared. we'll raise the caps as
+	 * and when, and only when, they are needed.
+	 */
+	if (cap_set_proc(zprivs_state.caps)) {
+		cap_t current_caps;
+		char *current_caps_text = NULL;
+		char *wanted_caps_text = NULL;
+
+		fprintf(stderr, "privs_init: initial cap_set_proc failed: %s\n",
+			safe_strerror(errno));
+
+		current_caps = cap_get_proc();
+		if (current_caps) {
+			current_caps_text = cap_to_text(current_caps, NULL);
+			cap_free(current_caps);
+		}
+
+		wanted_caps_text = cap_to_text(zprivs_state.caps, NULL);
+		fprintf(stderr, "Wanted caps: %s\n",
+			wanted_caps_text ? wanted_caps_text : "???");
+		fprintf(stderr, "Have   caps: %s\n",
+			current_caps_text ? current_caps_text : "???");
+		if (current_caps_text)
+			cap_free(current_caps_text);
+		if (wanted_caps_text)
+			cap_free(wanted_caps_text);
+
+		exit(1);
+	}
+
+	/* set methods for the caller to use */
+	zprivs->change = zprivs_change_caps;
+	zprivs->current_state = zprivs_state_caps;
+}
+
+static void zprivs_caps_terminate(void)
+{
+	/* Clear all capabilities, if we have any. */
+	if (zprivs_state.caps)
+		cap_clear(zprivs_state.caps);
+	else
+		return;
+
+	/* and boom, capabilities are gone forever */
+	if (cap_set_proc(zprivs_state.caps)) {
+		fprintf(stderr, "privs_terminate: cap_set_proc failed, %s",
+			safe_strerror(errno));
+		exit(1);
+	}
+
+	zprivs_state_free_caps();
+}
+#else /* !HAVE_LCAPS */
+#error "no Linux capabilities, dazed and confused..."
+#endif /* HAVE_LCAPS */
+#endif /* HAVE_CAPABILITIES */
+
+int zprivs_change_uid(zebra_privs_ops_t op)
+{
+	if (zprivs_state.zsuid == zprivs_state.zuid)
+		return 0;
+	if (op == ZPRIVS_RAISE)
+		return seteuid(zprivs_state.zsuid);
+	else if (op == ZPRIVS_LOWER)
+		return seteuid(zprivs_state.zuid);
+	else
+		return -1;
+}
+
+zebra_privs_current_t zprivs_state_uid(void)
+{
+	return ((zprivs_state.zuid == geteuid()) ? ZPRIVS_LOWERED
+						 : ZPRIVS_RAISED);
+}
+
+int zprivs_change_null(zebra_privs_ops_t op)
+{
+	return 0;
+}
+
+zebra_privs_current_t zprivs_state_null(void)
+{
+	return zprivs_null_state;
+}
+
+#ifndef HAVE_GETGROUPLIST
+/* Solaris 11 has no getgrouplist() */
+static int getgrouplist(const char *user, gid_t group, gid_t *groups,
+			int *ngroups)
+{
+	struct group *grp;
+	size_t usridx;
+	int pos = 0, ret;
+
+	if (pos < *ngroups)
+		groups[pos] = group;
+	pos++;
+
+	setgrent();
+	while ((grp = getgrent())) {
+		if (grp->gr_gid == group)
+			continue;
+		for (usridx = 0; grp->gr_mem[usridx] != NULL; usridx++)
+			if (!strcmp(grp->gr_mem[usridx], user)) {
+				if (pos < *ngroups)
+					groups[pos] = grp->gr_gid;
+				pos++;
+				break;
+			}
+	}
+	endgrent();
+
+	ret = (pos <= *ngroups) ? pos : -1;
+	*ngroups = pos;
+	return ret;
+}
+#endif /* HAVE_GETGROUPLIST */
+
+/*
+ * Helper function that locates a refcounting object to use: a process-wide
+ * object or a per-pthread object.
+ */
+static struct zebra_privs_refs_t *get_privs_refs(struct zebra_privs_t *privs)
+{
+	struct zebra_privs_refs_t *temp, *refs = NULL;
+	pthread_t tid;
+
+	if (privs_per_process)
+		refs = &(privs->process_refs);
+	else {
+		/* Locate - or create - the object for the current pthread. */
+		tid = pthread_self();
+
+		STAILQ_FOREACH(temp, &(privs->thread_refs), entry) {
+			if (pthread_equal(temp->tid, tid)) {
+				refs = temp;
+				break;
+			}
+		}
+
+		/* Need to create a new refcounting object. */
+		if (refs == NULL) {
+			refs = XCALLOC(MTYPE_PRIVS,
+				       sizeof(struct zebra_privs_refs_t));
+			refs->tid = tid;
+			STAILQ_INSERT_TAIL(&(privs->thread_refs), refs, entry);
+		}
+	}
+
+	return refs;
+}
+
+struct zebra_privs_t *_zprivs_raise(struct zebra_privs_t *privs,
+				    const char *funcname)
+{
+	int save_errno = errno;
+	struct zebra_privs_refs_t *refs;
+
+	if (!privs)
+		return NULL;
+
+	/*
+	 * Serialize 'raise' operations; particularly important for
+	 * OSes where privs are process-wide.
+	 */
+	frr_with_mutex (&(privs->mutex)) {
+		/* Locate ref-counting object to use */
+		refs = get_privs_refs(privs);
+
+		if (++(refs->refcount) == 1) {
+			errno = 0;
+			if (privs->change(ZPRIVS_RAISE)) {
+				zlog_err("%s: Failed to raise privileges (%s)",
+					 funcname, safe_strerror(errno));
+			}
+			errno = save_errno;
+			refs->raised_in_funcname = funcname;
+		}
+	}
+
+	return privs;
+}
+
+void _zprivs_lower(struct zebra_privs_t **privs)
+{
+	int save_errno = errno;
+	struct zebra_privs_refs_t *refs;
+
+	if (!*privs)
+		return;
+
+	/* Serialize 'lower privs' operation - particularly important
+	 * when OS privs are process-wide.
+	 */
+	frr_with_mutex (&(*privs)->mutex) {
+		refs = get_privs_refs(*privs);
+
+		if (--(refs->refcount) == 0) {
+			errno = 0;
+			if ((*privs)->change(ZPRIVS_LOWER)) {
+				zlog_err("%s: Failed to lower privileges (%s)",
+					 refs->raised_in_funcname,
+					 safe_strerror(errno));
+			}
+			errno = save_errno;
+			refs->raised_in_funcname = NULL;
+		}
+	}
+
+	*privs = NULL;
+}
+
+void zprivs_preinit(struct zebra_privs_t *zprivs)
+{
+	struct passwd *pwentry = NULL;
+	struct group *grentry = NULL;
+
+	if (!zprivs) {
+		fprintf(stderr, "zprivs_init: called with NULL arg!\n");
+		exit(1);
+	}
+
+	pthread_mutex_init(&(zprivs->mutex), NULL);
+	zprivs->process_refs.refcount = 0;
+	zprivs->process_refs.raised_in_funcname = NULL;
+	STAILQ_INIT(&zprivs->thread_refs);
+
+	if (zprivs->vty_group) {
+		/* in a "NULL" setup, this is allowed to fail too, but still
+		 * try. */
+		if ((grentry = getgrnam(zprivs->vty_group)))
+			zprivs_state.vtygrp = grentry->gr_gid;
+		else
+			zprivs_state.vtygrp = (gid_t)-1;
+	}
+
+	/* NULL privs */
+	if (!(zprivs->user || zprivs->group || zprivs->cap_num_p
+	      || zprivs->cap_num_i)) {
+		zprivs->change = zprivs_change_null;
+		zprivs->current_state = zprivs_state_null;
+		return;
+	}
+
+	if (zprivs->user) {
+		if ((pwentry = getpwnam(zprivs->user)) == NULL) {
+			/* cant use log.h here as it depends on vty */
+			fprintf(stderr,
+				"privs_init: could not lookup user %s\n",
+				zprivs->user);
+			exit(1);
+		}
+
+		zprivs_state.zuid = pwentry->pw_uid;
+		zprivs_state.zgid = pwentry->pw_gid;
+	}
+
+	grentry = NULL;
+
+	if (zprivs->group) {
+		if ((grentry = getgrnam(zprivs->group)) == NULL) {
+			fprintf(stderr,
+				"privs_init: could not lookup group %s\n",
+				zprivs->group);
+			exit(1);
+		}
+
+		zprivs_state.zgid = grentry->gr_gid;
+	}
+}
+
+struct zebra_privs_t *lib_privs;
+
+void zprivs_init(struct zebra_privs_t *zprivs)
+{
+	gid_t groups[NGROUPS_MAX] = {};
+	int i, ngroups = 0;
+	int found = 0;
+
+	/* NULL privs */
+	if (!(zprivs->user || zprivs->group || zprivs->cap_num_p
+	      || zprivs->cap_num_i))
+		return;
+
+	lib_privs = zprivs;
+
+	if (zprivs->user) {
+		ngroups = array_size(groups);
+		if (getgrouplist(zprivs->user, zprivs_state.zgid, groups,
+				 &ngroups)
+		    < 0) {
+			/* cant use log.h here as it depends on vty */
+			fprintf(stderr,
+				"privs_init: could not getgrouplist for user %s\n",
+				zprivs->user);
+			exit(1);
+		}
+	}
+
+	if (zprivs->vty_group)
+	/* Add the vty_group to the supplementary groups so it can be chowned to
+	   */
+	{
+		if (zprivs_state.vtygrp == (gid_t)-1) {
+			fprintf(stderr,
+				"privs_init: could not lookup vty group %s\n",
+				zprivs->vty_group);
+			exit(1);
+		}
+
+		for (i = 0; i < ngroups; i++)
+			if (groups[i] == zprivs_state.vtygrp) {
+				found++;
+				break;
+			}
+
+		if (!found) {
+			fprintf(stderr,
+				"privs_init: user(%s) is not part of vty group specified(%s)\n",
+				zprivs->user, zprivs->vty_group);
+			exit(1);
+		}
+		if (i >= ngroups && ngroups < (int)array_size(groups)) {
+			groups[i] = zprivs_state.vtygrp;
+		}
+	}
+
+	zprivs_state.zsuid = geteuid(); /* initial uid */
+	/* add groups only if we changed uid - otherwise skip */
+	if ((ngroups) && (zprivs_state.zsuid != zprivs_state.zuid)) {
+		if (setgroups(ngroups, groups)) {
+			fprintf(stderr, "privs_init: could not setgroups, %s\n",
+				safe_strerror(errno));
+			exit(1);
+		}
+	}
+
+	/* change gid only if we changed uid - otherwise skip */
+	if ((zprivs_state.zgid) && (zprivs_state.zsuid != zprivs_state.zuid)) {
+		/* change group now, forever. uid we do later */
+		if (setregid(zprivs_state.zgid, zprivs_state.zgid)) {
+			fprintf(stderr, "zprivs_init: could not setregid, %s\n",
+				safe_strerror(errno));
+			exit(1);
+		}
+	}
+
+#ifdef HAVE_CAPABILITIES
+	zprivs_caps_init(zprivs);
+
+	/*
+	 * If we have initialized the system with no requested
+	 * capabilities, change will not have been set
+	 * to anything by zprivs_caps_init, As such
+	 * we should make sure that when we attempt
+	 * to raize privileges that we actually have
+	 * a do nothing function to call instead of a
+	 * crash :).
+	 */
+	if (!zprivs->change)
+		zprivs->change = zprivs_change_null;
+
+#else  /* !HAVE_CAPABILITIES */
+	/* we dont have caps. we'll need to maintain rid and saved uid
+	 * and change euid back to saved uid (who we presume has all necessary
+	 * privileges) whenever we are asked to raise our privileges.
+	 *
+	 * This is not worth that much security wise, but all we can do.
+	 */
+	zprivs_state.zsuid = geteuid();
+	/* only change uid if we don't have the correct one */
+	if ((zprivs_state.zuid) && (zprivs_state.zsuid != zprivs_state.zuid)) {
+		if (setreuid(-1, zprivs_state.zuid)) {
+			fprintf(stderr,
+				"privs_init (uid): could not setreuid, %s\n",
+				safe_strerror(errno));
+			exit(1);
+		}
+	}
+
+	zprivs->change = zprivs_change_uid;
+	zprivs->current_state = zprivs_state_uid;
+#endif /* HAVE_CAPABILITIES */
+}
+
+void zprivs_terminate(struct zebra_privs_t *zprivs)
+{
+	struct zebra_privs_refs_t *refs;
+
+	lib_privs = NULL;
+
+	if (!zprivs) {
+		fprintf(stderr, "%s: no privs struct given, terminating",
+			__func__);
+		exit(0);
+	}
+
+#ifdef HAVE_CAPABILITIES
+	if (zprivs->user || zprivs->group || zprivs->cap_num_p
+	    || zprivs->cap_num_i)
+		zprivs_caps_terminate();
+#else  /* !HAVE_CAPABILITIES */
+	/* only change uid if we don't have the correct one */
+	if ((zprivs_state.zuid) && (zprivs_state.zsuid != zprivs_state.zuid)) {
+		if (setreuid(zprivs_state.zuid, zprivs_state.zuid)) {
+			fprintf(stderr,
+				"privs_terminate: could not setreuid, %s",
+				safe_strerror(errno));
+			exit(1);
+		}
+	}
+#endif /* HAVE_LCAPS */
+
+	while ((refs = STAILQ_FIRST(&(zprivs->thread_refs))) != NULL) {
+		STAILQ_REMOVE_HEAD(&(zprivs->thread_refs), entry);
+		XFREE(MTYPE_PRIVS, refs);
+	}
+
+	zprivs->change = zprivs_change_null;
+	zprivs->current_state = zprivs_state_null;
+	zprivs_null_state = ZPRIVS_LOWERED;
+	return;
+}
+
+void zprivs_get_ids(struct zprivs_ids_t *ids)
+{
+
+	ids->uid_priv = getuid();
+	(zprivs_state.zuid) ? (ids->uid_normal = zprivs_state.zuid)
+			    : (ids->uid_normal = (uid_t)-1);
+	(zprivs_state.zgid) ? (ids->gid_normal = zprivs_state.zgid)
+			    : (ids->gid_normal = (uid_t)-1);
+	(zprivs_state.vtygrp) ? (ids->gid_vty = zprivs_state.vtygrp)
+			      : (ids->gid_vty = (uid_t)-1);
+
+	return;
+}